diff options
Diffstat (limited to 'block')
46 files changed, 7809 insertions, 726 deletions
diff --git a/block/Kconfig b/block/Kconfig index 7f38e40fee0..2429515c05c 100644 --- a/block/Kconfig +++ b/block/Kconfig @@ -99,11 +99,16 @@ config BLK_DEV_THROTTLING See Documentation/cgroups/blkio-controller.txt for more information. -config CMDLINE_PARSER +config BLK_CMDLINE_PARSER bool "Block device command line partition parser" default n ---help--- - Parsing command line, get the partitions information. + Enabling this option allows you to specify the partition layout from + the kernel boot args. This is typically of use for embedded devices + which don't otherwise have any standardized method for listing the + partitions on a block device. + + See Documentation/block/cmdline-partition.txt for more information. menu "Partition Types" diff --git a/block/Makefile b/block/Makefile index 4fa4be544ec..a2ce6ac935e 100644 --- a/block/Makefile +++ b/block/Makefile @@ -2,12 +2,15 @@ # Makefile for the kernel block layer # -obj-$(CONFIG_BLOCK) := elevator.o blk-core.o blk-tag.o blk-sysfs.o \ +obj-$(CONFIG_BLOCK) := bio.o elevator.o blk-core.o blk-tag.o blk-sysfs.o \ blk-flush.o blk-settings.o blk-ioc.o blk-map.o \ blk-exec.o blk-merge.o blk-softirq.o blk-timeout.o \ - blk-iopoll.o blk-lib.o ioctl.o genhd.o scsi_ioctl.o \ - partition-generic.o partitions/ + blk-iopoll.o blk-lib.o blk-mq.o blk-mq-tag.o \ + blk-mq-sysfs.o blk-mq-cpu.o blk-mq-cpumap.o ioctl.o \ + genhd.o scsi_ioctl.o partition-generic.o ioprio.o \ + partitions/ +obj-$(CONFIG_BOUNCE) += bounce.o obj-$(CONFIG_BLK_DEV_BSG) += bsg.o obj-$(CONFIG_BLK_DEV_BSGLIB) += bsg-lib.o obj-$(CONFIG_BLK_CGROUP) += blk-cgroup.o @@ -18,4 +21,5 @@ obj-$(CONFIG_IOSCHED_CFQ) += cfq-iosched.o obj-$(CONFIG_BLOCK_COMPAT) += compat_ioctl.o obj-$(CONFIG_BLK_DEV_INTEGRITY) += blk-integrity.o -obj-$(CONFIG_CMDLINE_PARSER) += cmdline-parser.o +obj-$(CONFIG_BLK_CMDLINE_PARSER) += cmdline-parser.o +obj-$(CONFIG_BLK_DEV_INTEGRITY) += bio-integrity.o diff --git a/block/bio-integrity.c b/block/bio-integrity.c new file mode 100644 index 00000000000..9e241063a61 --- /dev/null +++ b/block/bio-integrity.c @@ -0,0 +1,657 @@ +/* + * bio-integrity.c - bio data integrity extensions + * + * Copyright (C) 2007, 2008, 2009 Oracle Corporation + * Written by: Martin K. Petersen <martin.petersen@oracle.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version + * 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; see the file COPYING. If not, write to + * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, + * USA. + * + */ + +#include <linux/blkdev.h> +#include <linux/mempool.h> +#include <linux/export.h> +#include <linux/bio.h> +#include <linux/workqueue.h> +#include <linux/slab.h> + +#define BIP_INLINE_VECS 4 + +static struct kmem_cache *bip_slab; +static struct workqueue_struct *kintegrityd_wq; + +/** + * bio_integrity_alloc - Allocate integrity payload and attach it to bio + * @bio: bio to attach integrity metadata to + * @gfp_mask: Memory allocation mask + * @nr_vecs: Number of integrity metadata scatter-gather elements + * + * Description: This function prepares a bio for attaching integrity + * metadata. nr_vecs specifies the maximum number of pages containing + * integrity metadata that can be attached. + */ +struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio, + gfp_t gfp_mask, + unsigned int nr_vecs) +{ + struct bio_integrity_payload *bip; + struct bio_set *bs = bio->bi_pool; + unsigned long idx = BIO_POOL_NONE; + unsigned inline_vecs; + + if (!bs) { + bip = kmalloc(sizeof(struct bio_integrity_payload) + + sizeof(struct bio_vec) * nr_vecs, gfp_mask); + inline_vecs = nr_vecs; + } else { + bip = mempool_alloc(bs->bio_integrity_pool, gfp_mask); + inline_vecs = BIP_INLINE_VECS; + } + + if (unlikely(!bip)) + return NULL; + + memset(bip, 0, sizeof(*bip)); + + if (nr_vecs > inline_vecs) { + bip->bip_vec = bvec_alloc(gfp_mask, nr_vecs, &idx, + bs->bvec_integrity_pool); + if (!bip->bip_vec) + goto err; + } else { + bip->bip_vec = bip->bip_inline_vecs; + } + + bip->bip_slab = idx; + bip->bip_bio = bio; + bio->bi_integrity = bip; + + return bip; +err: + mempool_free(bip, bs->bio_integrity_pool); + return NULL; +} +EXPORT_SYMBOL(bio_integrity_alloc); + +/** + * bio_integrity_free - Free bio integrity payload + * @bio: bio containing bip to be freed + * + * Description: Used to free the integrity portion of a bio. Usually + * called from bio_free(). + */ +void bio_integrity_free(struct bio *bio) +{ + struct bio_integrity_payload *bip = bio->bi_integrity; + struct bio_set *bs = bio->bi_pool; + + if (bip->bip_owns_buf) + kfree(bip->bip_buf); + + if (bs) { + if (bip->bip_slab != BIO_POOL_NONE) + bvec_free(bs->bvec_integrity_pool, bip->bip_vec, + bip->bip_slab); + + mempool_free(bip, bs->bio_integrity_pool); + } else { + kfree(bip); + } + + bio->bi_integrity = NULL; +} +EXPORT_SYMBOL(bio_integrity_free); + +static inline unsigned int bip_integrity_vecs(struct bio_integrity_payload *bip) +{ + if (bip->bip_slab == BIO_POOL_NONE) + return BIP_INLINE_VECS; + + return bvec_nr_vecs(bip->bip_slab); +} + +/** + * bio_integrity_add_page - Attach integrity metadata + * @bio: bio to update + * @page: page containing integrity metadata + * @len: number of bytes of integrity metadata in page + * @offset: start offset within page + * + * Description: Attach a page containing integrity metadata to bio. + */ +int bio_integrity_add_page(struct bio *bio, struct page *page, + unsigned int len, unsigned int offset) +{ + struct bio_integrity_payload *bip = bio->bi_integrity; + struct bio_vec *iv; + + if (bip->bip_vcnt >= bip_integrity_vecs(bip)) { + printk(KERN_ERR "%s: bip_vec full\n", __func__); + return 0; + } + + iv = bip->bip_vec + bip->bip_vcnt; + + iv->bv_page = page; + iv->bv_len = len; + iv->bv_offset = offset; + bip->bip_vcnt++; + + return len; +} +EXPORT_SYMBOL(bio_integrity_add_page); + +static int bdev_integrity_enabled(struct block_device *bdev, int rw) +{ + struct blk_integrity *bi = bdev_get_integrity(bdev); + + if (bi == NULL) + return 0; + + if (rw == READ && bi->verify_fn != NULL && + (bi->flags & INTEGRITY_FLAG_READ)) + return 1; + + if (rw == WRITE && bi->generate_fn != NULL && + (bi->flags & INTEGRITY_FLAG_WRITE)) + return 1; + + return 0; +} + +/** + * bio_integrity_enabled - Check whether integrity can be passed + * @bio: bio to check + * + * Description: Determines whether bio_integrity_prep() can be called + * on this bio or not. bio data direction and target device must be + * set prior to calling. The functions honors the write_generate and + * read_verify flags in sysfs. + */ +int bio_integrity_enabled(struct bio *bio) +{ + if (!bio_is_rw(bio)) + return 0; + + /* Already protected? */ + if (bio_integrity(bio)) + return 0; + + return bdev_integrity_enabled(bio->bi_bdev, bio_data_dir(bio)); +} +EXPORT_SYMBOL(bio_integrity_enabled); + +/** + * bio_integrity_hw_sectors - Convert 512b sectors to hardware ditto + * @bi: blk_integrity profile for device + * @sectors: Number of 512 sectors to convert + * + * Description: The block layer calculates everything in 512 byte + * sectors but integrity metadata is done in terms of the hardware + * sector size of the storage device. Convert the block layer sectors + * to physical sectors. + */ +static inline unsigned int bio_integrity_hw_sectors(struct blk_integrity *bi, + unsigned int sectors) +{ + /* At this point there are only 512b or 4096b DIF/EPP devices */ + if (bi->sector_size == 4096) + return sectors >>= 3; + + return sectors; +} + +static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi, + unsigned int sectors) +{ + return bio_integrity_hw_sectors(bi, sectors) * bi->tuple_size; +} + +/** + * bio_integrity_tag_size - Retrieve integrity tag space + * @bio: bio to inspect + * + * Description: Returns the maximum number of tag bytes that can be + * attached to this bio. Filesystems can use this to determine how + * much metadata to attach to an I/O. + */ +unsigned int bio_integrity_tag_size(struct bio *bio) +{ + struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); + + BUG_ON(bio->bi_iter.bi_size == 0); + + return bi->tag_size * (bio->bi_iter.bi_size / bi->sector_size); +} +EXPORT_SYMBOL(bio_integrity_tag_size); + +static int bio_integrity_tag(struct bio *bio, void *tag_buf, unsigned int len, + int set) +{ + struct bio_integrity_payload *bip = bio->bi_integrity; + struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); + unsigned int nr_sectors; + + BUG_ON(bip->bip_buf == NULL); + + if (bi->tag_size == 0) + return -1; + + nr_sectors = bio_integrity_hw_sectors(bi, + DIV_ROUND_UP(len, bi->tag_size)); + + if (nr_sectors * bi->tuple_size > bip->bip_iter.bi_size) { + printk(KERN_ERR "%s: tag too big for bio: %u > %u\n", __func__, + nr_sectors * bi->tuple_size, bip->bip_iter.bi_size); + return -1; + } + + if (set) + bi->set_tag_fn(bip->bip_buf, tag_buf, nr_sectors); + else + bi->get_tag_fn(bip->bip_buf, tag_buf, nr_sectors); + + return 0; +} + +/** + * bio_integrity_set_tag - Attach a tag buffer to a bio + * @bio: bio to attach buffer to + * @tag_buf: Pointer to a buffer containing tag data + * @len: Length of the included buffer + * + * Description: Use this function to tag a bio by leveraging the extra + * space provided by devices formatted with integrity protection. The + * size of the integrity buffer must be <= to the size reported by + * bio_integrity_tag_size(). + */ +int bio_integrity_set_tag(struct bio *bio, void *tag_buf, unsigned int len) +{ + BUG_ON(bio_data_dir(bio) != WRITE); + + return bio_integrity_tag(bio, tag_buf, len, 1); +} +EXPORT_SYMBOL(bio_integrity_set_tag); + +/** + * bio_integrity_get_tag - Retrieve a tag buffer from a bio + * @bio: bio to retrieve buffer from + * @tag_buf: Pointer to a buffer for the tag data + * @len: Length of the target buffer + * + * Description: Use this function to retrieve the tag buffer from a + * completed I/O. The size of the integrity buffer must be <= to the + * size reported by bio_integrity_tag_size(). + */ +int bio_integrity_get_tag(struct bio *bio, void *tag_buf, unsigned int len) +{ + BUG_ON(bio_data_dir(bio) != READ); + + return bio_integrity_tag(bio, tag_buf, len, 0); +} +EXPORT_SYMBOL(bio_integrity_get_tag); + +/** + * bio_integrity_generate_verify - Generate/verify integrity metadata for a bio + * @bio: bio to generate/verify integrity metadata for + * @operate: operate number, 1 for generate, 0 for verify + */ +static int bio_integrity_generate_verify(struct bio *bio, int operate) +{ + struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); + struct blk_integrity_exchg bix; + struct bio_vec *bv; + sector_t sector; + unsigned int sectors, ret = 0, i; + void *prot_buf = bio->bi_integrity->bip_buf; + + if (operate) + sector = bio->bi_iter.bi_sector; + else + sector = bio->bi_integrity->bip_iter.bi_sector; + + bix.disk_name = bio->bi_bdev->bd_disk->disk_name; + bix.sector_size = bi->sector_size; + + bio_for_each_segment_all(bv, bio, i) { + void *kaddr = kmap_atomic(bv->bv_page); + bix.data_buf = kaddr + bv->bv_offset; + bix.data_size = bv->bv_len; + bix.prot_buf = prot_buf; + bix.sector = sector; + + if (operate) + bi->generate_fn(&bix); + else { + ret = bi->verify_fn(&bix); + if (ret) { + kunmap_atomic(kaddr); + return ret; + } + } + + sectors = bv->bv_len / bi->sector_size; + sector += sectors; + prot_buf += sectors * bi->tuple_size; + + kunmap_atomic(kaddr); + } + return ret; +} + +/** + * bio_integrity_generate - Generate integrity metadata for a bio + * @bio: bio to generate integrity metadata for + * + * Description: Generates integrity metadata for a bio by calling the + * block device's generation callback function. The bio must have a + * bip attached with enough room to accommodate the generated + * integrity metadata. + */ +static void bio_integrity_generate(struct bio *bio) +{ + bio_integrity_generate_verify(bio, 1); +} + +static inline unsigned short blk_integrity_tuple_size(struct blk_integrity *bi) +{ + if (bi) + return bi->tuple_size; + + return 0; +} + +/** + * bio_integrity_prep - Prepare bio for integrity I/O + * @bio: bio to prepare + * + * Description: Allocates a buffer for integrity metadata, maps the + * pages and attaches them to a bio. The bio must have data + * direction, target device and start sector set priot to calling. In + * the WRITE case, integrity metadata will be generated using the + * block device's integrity function. In the READ case, the buffer + * will be prepared for DMA and a suitable end_io handler set up. + */ +int bio_integrity_prep(struct bio *bio) +{ + struct bio_integrity_payload *bip; + struct blk_integrity *bi; + struct request_queue *q; + void *buf; + unsigned long start, end; + unsigned int len, nr_pages; + unsigned int bytes, offset, i; + unsigned int sectors; + + bi = bdev_get_integrity(bio->bi_bdev); + q = bdev_get_queue(bio->bi_bdev); + BUG_ON(bi == NULL); + BUG_ON(bio_integrity(bio)); + + sectors = bio_integrity_hw_sectors(bi, bio_sectors(bio)); + + /* Allocate kernel buffer for protection data */ + len = sectors * blk_integrity_tuple_size(bi); + buf = kmalloc(len, GFP_NOIO | q->bounce_gfp); + if (unlikely(buf == NULL)) { + printk(KERN_ERR "could not allocate integrity buffer\n"); + return -ENOMEM; + } + + end = (((unsigned long) buf) + len + PAGE_SIZE - 1) >> PAGE_SHIFT; + start = ((unsigned long) buf) >> PAGE_SHIFT; + nr_pages = end - start; + + /* Allocate bio integrity payload and integrity vectors */ + bip = bio_integrity_alloc(bio, GFP_NOIO, nr_pages); + if (unlikely(bip == NULL)) { + printk(KERN_ERR "could not allocate data integrity bioset\n"); + kfree(buf); + return -EIO; + } + + bip->bip_owns_buf = 1; + bip->bip_buf = buf; + bip->bip_iter.bi_size = len; + bip->bip_iter.bi_sector = bio->bi_iter.bi_sector; + + /* Map it */ + offset = offset_in_page(buf); + for (i = 0 ; i < nr_pages ; i++) { + int ret; + bytes = PAGE_SIZE - offset; + + if (len <= 0) + break; + + if (bytes > len) + bytes = len; + + ret = bio_integrity_add_page(bio, virt_to_page(buf), + bytes, offset); + + if (ret == 0) + return 0; + + if (ret < bytes) + break; + + buf += bytes; + len -= bytes; + offset = 0; + } + + /* Install custom I/O completion handler if read verify is enabled */ + if (bio_data_dir(bio) == READ) { + bip->bip_end_io = bio->bi_end_io; + bio->bi_end_io = bio_integrity_endio; + } + + /* Auto-generate integrity metadata if this is a write */ + if (bio_data_dir(bio) == WRITE) + bio_integrity_generate(bio); + + return 0; +} +EXPORT_SYMBOL(bio_integrity_prep); + +/** + * bio_integrity_verify - Verify integrity metadata for a bio + * @bio: bio to verify + * + * Description: This function is called to verify the integrity of a + * bio. The data in the bio io_vec is compared to the integrity + * metadata returned by the HBA. + */ +static int bio_integrity_verify(struct bio *bio) +{ + return bio_integrity_generate_verify(bio, 0); +} + +/** + * bio_integrity_verify_fn - Integrity I/O completion worker + * @work: Work struct stored in bio to be verified + * + * Description: This workqueue function is called to complete a READ + * request. The function verifies the transferred integrity metadata + * and then calls the original bio end_io function. + */ +static void bio_integrity_verify_fn(struct work_struct *work) +{ + struct bio_integrity_payload *bip = + container_of(work, struct bio_integrity_payload, bip_work); + struct bio *bio = bip->bip_bio; + int error; + + error = bio_integrity_verify(bio); + + /* Restore original bio completion handler */ + bio->bi_end_io = bip->bip_end_io; + bio_endio_nodec(bio, error); +} + +/** + * bio_integrity_endio - Integrity I/O completion function + * @bio: Protected bio + * @error: Pointer to errno + * + * Description: Completion for integrity I/O + * + * Normally I/O completion is done in interrupt context. However, + * verifying I/O integrity is a time-consuming task which must be run + * in process context. This function postpones completion + * accordingly. + */ +void bio_integrity_endio(struct bio *bio, int error) +{ + struct bio_integrity_payload *bip = bio->bi_integrity; + + BUG_ON(bip->bip_bio != bio); + + /* In case of an I/O error there is no point in verifying the + * integrity metadata. Restore original bio end_io handler + * and run it. + */ + if (error) { + bio->bi_end_io = bip->bip_end_io; + bio_endio(bio, error); + + return; + } + + INIT_WORK(&bip->bip_work, bio_integrity_verify_fn); + queue_work(kintegrityd_wq, &bip->bip_work); +} +EXPORT_SYMBOL(bio_integrity_endio); + +/** + * bio_integrity_advance - Advance integrity vector + * @bio: bio whose integrity vector to update + * @bytes_done: number of data bytes that have been completed + * + * Description: This function calculates how many integrity bytes the + * number of completed data bytes correspond to and advances the + * integrity vector accordingly. + */ +void bio_integrity_advance(struct bio *bio, unsigned int bytes_done) +{ + struct bio_integrity_payload *bip = bio->bi_integrity; + struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); + unsigned bytes = bio_integrity_bytes(bi, bytes_done >> 9); + + bvec_iter_advance(bip->bip_vec, &bip->bip_iter, bytes); +} +EXPORT_SYMBOL(bio_integrity_advance); + +/** + * bio_integrity_trim - Trim integrity vector + * @bio: bio whose integrity vector to update + * @offset: offset to first data sector + * @sectors: number of data sectors + * + * Description: Used to trim the integrity vector in a cloned bio. + * The ivec will be advanced corresponding to 'offset' data sectors + * and the length will be truncated corresponding to 'len' data + * sectors. + */ +void bio_integrity_trim(struct bio *bio, unsigned int offset, + unsigned int sectors) +{ + struct bio_integrity_payload *bip = bio->bi_integrity; + struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); + + bio_integrity_advance(bio, offset << 9); + bip->bip_iter.bi_size = bio_integrity_bytes(bi, sectors); +} +EXPORT_SYMBOL(bio_integrity_trim); + +/** + * bio_integrity_clone - Callback for cloning bios with integrity metadata + * @bio: New bio + * @bio_src: Original bio + * @gfp_mask: Memory allocation mask + * + * Description: Called to allocate a bip when cloning a bio + */ +int bio_integrity_clone(struct bio *bio, struct bio *bio_src, + gfp_t gfp_mask) +{ + struct bio_integrity_payload *bip_src = bio_src->bi_integrity; + struct bio_integrity_payload *bip; + + BUG_ON(bip_src == NULL); + + bip = bio_integrity_alloc(bio, gfp_mask, bip_src->bip_vcnt); + + if (bip == NULL) + return -EIO; + + memcpy(bip->bip_vec, bip_src->bip_vec, + bip_src->bip_vcnt * sizeof(struct bio_vec)); + + bip->bip_vcnt = bip_src->bip_vcnt; + bip->bip_iter = bip_src->bip_iter; + + return 0; +} +EXPORT_SYMBOL(bio_integrity_clone); + +int bioset_integrity_create(struct bio_set *bs, int pool_size) +{ + if (bs->bio_integrity_pool) + return 0; + + bs->bio_integrity_pool = mempool_create_slab_pool(pool_size, bip_slab); + if (!bs->bio_integrity_pool) + return -1; + + bs->bvec_integrity_pool = biovec_create_pool(pool_size); + if (!bs->bvec_integrity_pool) { + mempool_destroy(bs->bio_integrity_pool); + return -1; + } + + return 0; +} +EXPORT_SYMBOL(bioset_integrity_create); + +void bioset_integrity_free(struct bio_set *bs) +{ + if (bs->bio_integrity_pool) + mempool_destroy(bs->bio_integrity_pool); + + if (bs->bvec_integrity_pool) + mempool_destroy(bs->bvec_integrity_pool); +} +EXPORT_SYMBOL(bioset_integrity_free); + +void __init bio_integrity_init(void) +{ + /* + * kintegrityd won't block much but may burn a lot of CPU cycles. + * Make it highpri CPU intensive wq with max concurrency of 1. + */ + kintegrityd_wq = alloc_workqueue("kintegrityd", WQ_MEM_RECLAIM | + WQ_HIGHPRI | WQ_CPU_INTENSIVE, 1); + if (!kintegrityd_wq) + panic("Failed to create kintegrityd\n"); + + bip_slab = kmem_cache_create("bio_integrity_payload", + sizeof(struct bio_integrity_payload) + + sizeof(struct bio_vec) * BIP_INLINE_VECS, + 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); + if (!bip_slab) + panic("Failed to create slab\n"); +} diff --git a/block/bio.c b/block/bio.c new file mode 100644 index 00000000000..0ec61c9e536 --- /dev/null +++ b/block/bio.c @@ -0,0 +1,2052 @@ +/* + * Copyright (C) 2001 Jens Axboe <axboe@kernel.dk> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public Licens + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111- + * + */ +#include <linux/mm.h> +#include <linux/swap.h> +#include <linux/bio.h> +#include <linux/blkdev.h> +#include <linux/uio.h> +#include <linux/iocontext.h> +#include <linux/slab.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/export.h> +#include <linux/mempool.h> +#include <linux/workqueue.h> +#include <linux/cgroup.h> +#include <scsi/sg.h> /* for struct sg_iovec */ + +#include <trace/events/block.h> + +/* + * Test patch to inline a certain number of bi_io_vec's inside the bio + * itself, to shrink a bio data allocation from two mempool calls to one + */ +#define BIO_INLINE_VECS 4 + +/* + * if you change this list, also change bvec_alloc or things will + * break badly! cannot be bigger than what you can fit into an + * unsigned short + */ +#define BV(x) { .nr_vecs = x, .name = "biovec-"__stringify(x) } +static struct biovec_slab bvec_slabs[BIOVEC_NR_POOLS] __read_mostly = { + BV(1), BV(4), BV(16), BV(64), BV(128), BV(BIO_MAX_PAGES), +}; +#undef BV + +/* + * fs_bio_set is the bio_set containing bio and iovec memory pools used by + * IO code that does not need private memory pools. + */ +struct bio_set *fs_bio_set; +EXPORT_SYMBOL(fs_bio_set); + +/* + * Our slab pool management + */ +struct bio_slab { + struct kmem_cache *slab; + unsigned int slab_ref; + unsigned int slab_size; + char name[8]; +}; +static DEFINE_MUTEX(bio_slab_lock); +static struct bio_slab *bio_slabs; +static unsigned int bio_slab_nr, bio_slab_max; + +static struct kmem_cache *bio_find_or_create_slab(unsigned int extra_size) +{ + unsigned int sz = sizeof(struct bio) + extra_size; + struct kmem_cache *slab = NULL; + struct bio_slab *bslab, *new_bio_slabs; + unsigned int new_bio_slab_max; + unsigned int i, entry = -1; + + mutex_lock(&bio_slab_lock); + + i = 0; + while (i < bio_slab_nr) { + bslab = &bio_slabs[i]; + + if (!bslab->slab && entry == -1) + entry = i; + else if (bslab->slab_size == sz) { + slab = bslab->slab; + bslab->slab_ref++; + break; + } + i++; + } + + if (slab) + goto out_unlock; + + if (bio_slab_nr == bio_slab_max && entry == -1) { + new_bio_slab_max = bio_slab_max << 1; + new_bio_slabs = krealloc(bio_slabs, + new_bio_slab_max * sizeof(struct bio_slab), + GFP_KERNEL); + if (!new_bio_slabs) + goto out_unlock; + bio_slab_max = new_bio_slab_max; + bio_slabs = new_bio_slabs; + } + if (entry == -1) + entry = bio_slab_nr++; + + bslab = &bio_slabs[entry]; + + snprintf(bslab->name, sizeof(bslab->name), "bio-%d", entry); + slab = kmem_cache_create(bslab->name, sz, 0, SLAB_HWCACHE_ALIGN, NULL); + if (!slab) + goto out_unlock; + + bslab->slab = slab; + bslab->slab_ref = 1; + bslab->slab_size = sz; +out_unlock: + mutex_unlock(&bio_slab_lock); + return slab; +} + +static void bio_put_slab(struct bio_set *bs) +{ + struct bio_slab *bslab = NULL; + unsigned int i; + + mutex_lock(&bio_slab_lock); + + for (i = 0; i < bio_slab_nr; i++) { + if (bs->bio_slab == bio_slabs[i].slab) { + bslab = &bio_slabs[i]; + break; + } + } + + if (WARN(!bslab, KERN_ERR "bio: unable to find slab!\n")) + goto out; + + WARN_ON(!bslab->slab_ref); + + if (--bslab->slab_ref) + goto out; + + kmem_cache_destroy(bslab->slab); + bslab->slab = NULL; + +out: + mutex_unlock(&bio_slab_lock); +} + +unsigned int bvec_nr_vecs(unsigned short idx) +{ + return bvec_slabs[idx].nr_vecs; +} + +void bvec_free(mempool_t *pool, struct bio_vec *bv, unsigned int idx) +{ + BIO_BUG_ON(idx >= BIOVEC_NR_POOLS); + + if (idx == BIOVEC_MAX_IDX) + mempool_free(bv, pool); + else { + struct biovec_slab *bvs = bvec_slabs + idx; + + kmem_cache_free(bvs->slab, bv); + } +} + +struct bio_vec *bvec_alloc(gfp_t gfp_mask, int nr, unsigned long *idx, + mempool_t *pool) +{ + struct bio_vec *bvl; + + /* + * see comment near bvec_array define! + */ + switch (nr) { + case 1: + *idx = 0; + break; + case 2 ... 4: + *idx = 1; + break; + case 5 ... 16: + *idx = 2; + break; + case 17 ... 64: + *idx = 3; + break; + case 65 ... 128: + *idx = 4; + break; + case 129 ... BIO_MAX_PAGES: + *idx = 5; + break; + default: + return NULL; + } + + /* + * idx now points to the pool we want to allocate from. only the + * 1-vec entry pool is mempool backed. + */ + if (*idx == BIOVEC_MAX_IDX) { +fallback: + bvl = mempool_alloc(pool, gfp_mask); + } else { + struct biovec_slab *bvs = bvec_slabs + *idx; + gfp_t __gfp_mask = gfp_mask & ~(__GFP_WAIT | __GFP_IO); + + /* + * Make this allocation restricted and don't dump info on + * allocation failures, since we'll fallback to the mempool + * in case of failure. + */ + __gfp_mask |= __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN; + + /* + * Try a slab allocation. If this fails and __GFP_WAIT + * is set, retry with the 1-entry mempool + */ + bvl = kmem_cache_alloc(bvs->slab, __gfp_mask); + if (unlikely(!bvl && (gfp_mask & __GFP_WAIT))) { + *idx = BIOVEC_MAX_IDX; + goto fallback; + } + } + + return bvl; +} + +static void __bio_free(struct bio *bio) +{ + bio_disassociate_task(bio); + + if (bio_integrity(bio)) + bio_integrity_free(bio); +} + +static void bio_free(struct bio *bio) +{ + struct bio_set *bs = bio->bi_pool; + void *p; + + __bio_free(bio); + + if (bs) { + if (bio_flagged(bio, BIO_OWNS_VEC)) + bvec_free(bs->bvec_pool, bio->bi_io_vec, BIO_POOL_IDX(bio)); + + /* + * If we have front padding, adjust the bio pointer before freeing + */ + p = bio; + p -= bs->front_pad; + + mempool_free(p, bs->bio_pool); + } else { + /* Bio was allocated by bio_kmalloc() */ + kfree(bio); + } +} + +void bio_init(struct bio *bio) +{ + memset(bio, 0, sizeof(*bio)); + bio->bi_flags = 1 << BIO_UPTODATE; + atomic_set(&bio->bi_remaining, 1); + atomic_set(&bio->bi_cnt, 1); +} +EXPORT_SYMBOL(bio_init); + +/** + * bio_reset - reinitialize a bio + * @bio: bio to reset + * + * Description: + * After calling bio_reset(), @bio will be in the same state as a freshly + * allocated bio returned bio bio_alloc_bioset() - the only fields that are + * preserved are the ones that are initialized by bio_alloc_bioset(). See + * comment in struct bio. + */ +void bio_reset(struct bio *bio) +{ + unsigned long flags = bio->bi_flags & (~0UL << BIO_RESET_BITS); + + __bio_free(bio); + + memset(bio, 0, BIO_RESET_BYTES); + bio->bi_flags = flags|(1 << BIO_UPTODATE); + atomic_set(&bio->bi_remaining, 1); +} +EXPORT_SYMBOL(bio_reset); + +static void bio_chain_endio(struct bio *bio, int error) +{ + bio_endio(bio->bi_private, error); + bio_put(bio); +} + +/** + * bio_chain - chain bio completions + * @bio: the target bio + * @parent: the @bio's parent bio + * + * The caller won't have a bi_end_io called when @bio completes - instead, + * @parent's bi_end_io won't be called until both @parent and @bio have + * completed; the chained bio will also be freed when it completes. + * + * The caller must not set bi_private or bi_end_io in @bio. + */ +void bio_chain(struct bio *bio, struct bio *parent) +{ + BUG_ON(bio->bi_private || bio->bi_end_io); + + bio->bi_private = parent; + bio->bi_end_io = bio_chain_endio; + atomic_inc(&parent->bi_remaining); +} +EXPORT_SYMBOL(bio_chain); + +static void bio_alloc_rescue(struct work_struct *work) +{ + struct bio_set *bs = container_of(work, struct bio_set, rescue_work); + struct bio *bio; + + while (1) { + spin_lock(&bs->rescue_lock); + bio = bio_list_pop(&bs->rescue_list); + spin_unlock(&bs->rescue_lock); + + if (!bio) + break; + + generic_make_request(bio); + } +} + +static void punt_bios_to_rescuer(struct bio_set *bs) +{ + struct bio_list punt, nopunt; + struct bio *bio; + + /* + * In order to guarantee forward progress we must punt only bios that + * were allocated from this bio_set; otherwise, if there was a bio on + * there for a stacking driver higher up in the stack, processing it + * could require allocating bios from this bio_set, and doing that from + * our own rescuer would be bad. + * + * Since bio lists are singly linked, pop them all instead of trying to + * remove from the middle of the list: + */ + + bio_list_init(&punt); + bio_list_init(&nopunt); + + while ((bio = bio_list_pop(current->bio_list))) + bio_list_add(bio->bi_pool == bs ? &punt : &nopunt, bio); + + *current->bio_list = nopunt; + + spin_lock(&bs->rescue_lock); + bio_list_merge(&bs->rescue_list, &punt); + spin_unlock(&bs->rescue_lock); + + queue_work(bs->rescue_workqueue, &bs->rescue_work); +} + +/** + * bio_alloc_bioset - allocate a bio for I/O + * @gfp_mask: the GFP_ mask given to the slab allocator + * @nr_iovecs: number of iovecs to pre-allocate + * @bs: the bio_set to allocate from. + * + * Description: + * If @bs is NULL, uses kmalloc() to allocate the bio; else the allocation is + * backed by the @bs's mempool. + * + * When @bs is not NULL, if %__GFP_WAIT is set then bio_alloc will always be + * able to allocate a bio. This is due to the mempool guarantees. To make this + * work, callers must never allocate more than 1 bio at a time from this pool. + * Callers that need to allocate more than 1 bio must always submit the + * previously allocated bio for IO before attempting to allocate a new one. + * Failure to do so can cause deadlocks under memory pressure. + * + * Note that when running under generic_make_request() (i.e. any block + * driver), bios are not submitted until after you return - see the code in + * generic_make_request() that converts recursion into iteration, to prevent + * stack overflows. + * + * This would normally mean allocating multiple bios under + * generic_make_request() would be susceptible to deadlocks, but we have + * deadlock avoidance code that resubmits any blocked bios from a rescuer + * thread. + * + * However, we do not guarantee forward progress for allocations from other + * mempools. Doing multiple allocations from the same mempool under + * generic_make_request() should be avoided - instead, use bio_set's front_pad + * for per bio allocations. + * + * RETURNS: + * Pointer to new bio on success, NULL on failure. + */ +struct bio *bio_alloc_bioset(gfp_t gfp_mask, int nr_iovecs, struct bio_set *bs) +{ + gfp_t saved_gfp = gfp_mask; + unsigned front_pad; + unsigned inline_vecs; + unsigned long idx = BIO_POOL_NONE; + struct bio_vec *bvl = NULL; + struct bio *bio; + void *p; + + if (!bs) { + if (nr_iovecs > UIO_MAXIOV) + return NULL; + + p = kmalloc(sizeof(struct bio) + + nr_iovecs * sizeof(struct bio_vec), + gfp_mask); + front_pad = 0; + inline_vecs = nr_iovecs; + } else { + /* + * generic_make_request() converts recursion to iteration; this + * means if we're running beneath it, any bios we allocate and + * submit will not be submitted (and thus freed) until after we + * return. + * + * This exposes us to a potential deadlock if we allocate + * multiple bios from the same bio_set() while running + * underneath generic_make_request(). If we were to allocate + * multiple bios (say a stacking block driver that was splitting + * bios), we would deadlock if we exhausted the mempool's + * reserve. + * + * We solve this, and guarantee forward progress, with a rescuer + * workqueue per bio_set. If we go to allocate and there are + * bios on current->bio_list, we first try the allocation + * without __GFP_WAIT; if that fails, we punt those bios we + * would be blocking to the rescuer workqueue before we retry + * with the original gfp_flags. + */ + + if (current->bio_list && !bio_list_empty(current->bio_list)) + gfp_mask &= ~__GFP_WAIT; + + p = mempool_alloc(bs->bio_pool, gfp_mask); + if (!p && gfp_mask != saved_gfp) { + punt_bios_to_rescuer(bs); + gfp_mask = saved_gfp; + p = mempool_alloc(bs->bio_pool, gfp_mask); + } + + front_pad = bs->front_pad; + inline_vecs = BIO_INLINE_VECS; + } + + if (unlikely(!p)) + return NULL; + + bio = p + front_pad; + bio_init(bio); + + if (nr_iovecs > inline_vecs) { + bvl = bvec_alloc(gfp_mask, nr_iovecs, &idx, bs->bvec_pool); + if (!bvl && gfp_mask != saved_gfp) { + punt_bios_to_rescuer(bs); + gfp_mask = saved_gfp; + bvl = bvec_alloc(gfp_mask, nr_iovecs, &idx, bs->bvec_pool); + } + + if (unlikely(!bvl)) + goto err_free; + + bio->bi_flags |= 1 << BIO_OWNS_VEC; + } else if (nr_iovecs) { + bvl = bio->bi_inline_vecs; + } + + bio->bi_pool = bs; + bio->bi_flags |= idx << BIO_POOL_OFFSET; + bio->bi_max_vecs = nr_iovecs; + bio->bi_io_vec = bvl; + return bio; + +err_free: + mempool_free(p, bs->bio_pool); + return NULL; +} +EXPORT_SYMBOL(bio_alloc_bioset); + +void zero_fill_bio(struct bio *bio) +{ + unsigned long flags; + struct bio_vec bv; + struct bvec_iter iter; + + bio_for_each_segment(bv, bio, iter) { + char *data = bvec_kmap_irq(&bv, &flags); + memset(data, 0, bv.bv_len); + flush_dcache_page(bv.bv_page); + bvec_kunmap_irq(data, &flags); + } +} +EXPORT_SYMBOL(zero_fill_bio); + +/** + * bio_put - release a reference to a bio + * @bio: bio to release reference to + * + * Description: + * Put a reference to a &struct bio, either one you have gotten with + * bio_alloc, bio_get or bio_clone. The last put of a bio will free it. + **/ +void bio_put(struct bio *bio) +{ + BIO_BUG_ON(!atomic_read(&bio->bi_cnt)); + + /* + * last put frees it + */ + if (atomic_dec_and_test(&bio->bi_cnt)) + bio_free(bio); +} +EXPORT_SYMBOL(bio_put); + +inline int bio_phys_segments(struct request_queue *q, struct bio *bio) +{ + if (unlikely(!bio_flagged(bio, BIO_SEG_VALID))) + blk_recount_segments(q, bio); + + return bio->bi_phys_segments; +} +EXPORT_SYMBOL(bio_phys_segments); + +/** + * __bio_clone_fast - clone a bio that shares the original bio's biovec + * @bio: destination bio + * @bio_src: bio to clone + * + * Clone a &bio. Caller will own the returned bio, but not + * the actual data it points to. Reference count of returned + * bio will be one. + * + * Caller must ensure that @bio_src is not freed before @bio. + */ +void __bio_clone_fast(struct bio *bio, struct bio *bio_src) +{ + BUG_ON(bio->bi_pool && BIO_POOL_IDX(bio) != BIO_POOL_NONE); + + /* + * most users will be overriding ->bi_bdev with a new target, + * so we don't set nor calculate new physical/hw segment counts here + */ + bio->bi_bdev = bio_src->bi_bdev; + bio->bi_flags |= 1 << BIO_CLONED; + bio->bi_rw = bio_src->bi_rw; + bio->bi_iter = bio_src->bi_iter; + bio->bi_io_vec = bio_src->bi_io_vec; +} +EXPORT_SYMBOL(__bio_clone_fast); + +/** + * bio_clone_fast - clone a bio that shares the original bio's biovec + * @bio: bio to clone + * @gfp_mask: allocation priority + * @bs: bio_set to allocate from + * + * Like __bio_clone_fast, only also allocates the returned bio + */ +struct bio *bio_clone_fast(struct bio *bio, gfp_t gfp_mask, struct bio_set *bs) +{ + struct bio *b; + + b = bio_alloc_bioset(gfp_mask, 0, bs); + if (!b) + return NULL; + + __bio_clone_fast(b, bio); + + if (bio_integrity(bio)) { + int ret; + + ret = bio_integrity_clone(b, bio, gfp_mask); + + if (ret < 0) { + bio_put(b); + return NULL; + } + } + + return b; +} +EXPORT_SYMBOL(bio_clone_fast); + +/** + * bio_clone_bioset - clone a bio + * @bio_src: bio to clone + * @gfp_mask: allocation priority + * @bs: bio_set to allocate from + * + * Clone bio. Caller will own the returned bio, but not the actual data it + * points to. Reference count of returned bio will be one. + */ +struct bio *bio_clone_bioset(struct bio *bio_src, gfp_t gfp_mask, + struct bio_set *bs) +{ + struct bvec_iter iter; + struct bio_vec bv; + struct bio *bio; + + /* + * Pre immutable biovecs, __bio_clone() used to just do a memcpy from + * bio_src->bi_io_vec to bio->bi_io_vec. + * + * We can't do that anymore, because: + * + * - The point of cloning the biovec is to produce a bio with a biovec + * the caller can modify: bi_idx and bi_bvec_done should be 0. + * + * - The original bio could've had more than BIO_MAX_PAGES biovecs; if + * we tried to clone the whole thing bio_alloc_bioset() would fail. + * But the clone should succeed as long as the number of biovecs we + * actually need to allocate is fewer than BIO_MAX_PAGES. + * + * - Lastly, bi_vcnt should not be looked at or relied upon by code + * that does not own the bio - reason being drivers don't use it for + * iterating over the biovec anymore, so expecting it to be kept up + * to date (i.e. for clones that share the parent biovec) is just + * asking for trouble and would force extra work on + * __bio_clone_fast() anyways. + */ + + bio = bio_alloc_bioset(gfp_mask, bio_segments(bio_src), bs); + if (!bio) + return NULL; + + bio->bi_bdev = bio_src->bi_bdev; + bio->bi_rw = bio_src->bi_rw; + bio->bi_iter.bi_sector = bio_src->bi_iter.bi_sector; + bio->bi_iter.bi_size = bio_src->bi_iter.bi_size; + + if (bio->bi_rw & REQ_DISCARD) + goto integrity_clone; + + if (bio->bi_rw & REQ_WRITE_SAME) { + bio->bi_io_vec[bio->bi_vcnt++] = bio_src->bi_io_vec[0]; + goto integrity_clone; + } + + bio_for_each_segment(bv, bio_src, iter) + bio->bi_io_vec[bio->bi_vcnt++] = bv; + +integrity_clone: + if (bio_integrity(bio_src)) { + int ret; + + ret = bio_integrity_clone(bio, bio_src, gfp_mask); + if (ret < 0) { + bio_put(bio); + return NULL; + } + } + + return bio; +} +EXPORT_SYMBOL(bio_clone_bioset); + +/** + * bio_get_nr_vecs - return approx number of vecs + * @bdev: I/O target + * + * Return the approximate number of pages we can send to this target. + * There's no guarantee that you will be able to fit this number of pages + * into a bio, it does not account for dynamic restrictions that vary + * on offset. + */ +int bio_get_nr_vecs(struct block_device *bdev) +{ + struct request_queue *q = bdev_get_queue(bdev); + int nr_pages; + + nr_pages = min_t(unsigned, + queue_max_segments(q), + queue_max_sectors(q) / (PAGE_SIZE >> 9) + 1); + + return min_t(unsigned, nr_pages, BIO_MAX_PAGES); + +} +EXPORT_SYMBOL(bio_get_nr_vecs); + +static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page + *page, unsigned int len, unsigned int offset, + unsigned int max_sectors) +{ + int retried_segments = 0; + struct bio_vec *bvec; + + /* + * cloned bio must not modify vec list + */ + if (unlikely(bio_flagged(bio, BIO_CLONED))) + return 0; + + if (((bio->bi_iter.bi_size + len) >> 9) > max_sectors) + return 0; + + /* + * For filesystems with a blocksize smaller than the pagesize + * we will often be called with the same page as last time and + * a consecutive offset. Optimize this special case. + */ + if (bio->bi_vcnt > 0) { + struct bio_vec *prev = &bio->bi_io_vec[bio->bi_vcnt - 1]; + + if (page == prev->bv_page && + offset == prev->bv_offset + prev->bv_len) { + unsigned int prev_bv_len = prev->bv_len; + prev->bv_len += len; + + if (q->merge_bvec_fn) { + struct bvec_merge_data bvm = { + /* prev_bvec is already charged in + bi_size, discharge it in order to + simulate merging updated prev_bvec + as new bvec. */ + .bi_bdev = bio->bi_bdev, + .bi_sector = bio->bi_iter.bi_sector, + .bi_size = bio->bi_iter.bi_size - + prev_bv_len, + .bi_rw = bio->bi_rw, + }; + + if (q->merge_bvec_fn(q, &bvm, prev) < prev->bv_len) { + prev->bv_len -= len; + return 0; + } + } + + goto done; + } + + /* + * If the queue doesn't support SG gaps and adding this + * offset would create a gap, disallow it. + */ + if (q->queue_flags & (1 << QUEUE_FLAG_SG_GAPS) && + bvec_gap_to_prev(prev, offset)) + return 0; + } + + if (bio->bi_vcnt >= bio->bi_max_vecs) + return 0; + + /* + * we might lose a segment or two here, but rather that than + * make this too complex. + */ + + while (bio->bi_phys_segments >= queue_max_segments(q)) { + + if (retried_segments) + return 0; + + retried_segments = 1; + blk_recount_segments(q, bio); + } + + /* + * setup the new entry, we might clear it again later if we + * cannot add the page + */ + bvec = &bio->bi_io_vec[bio->bi_vcnt]; + bvec->bv_page = page; + bvec->bv_len = len; + bvec->bv_offset = offset; + + /* + * if queue has other restrictions (eg varying max sector size + * depending on offset), it can specify a merge_bvec_fn in the + * queue to get further control + */ + if (q->merge_bvec_fn) { + struct bvec_merge_data bvm = { + .bi_bdev = bio->bi_bdev, + .bi_sector = bio->bi_iter.bi_sector, + .bi_size = bio->bi_iter.bi_size, + .bi_rw = bio->bi_rw, + }; + + /* + * merge_bvec_fn() returns number of bytes it can accept + * at this offset + */ + if (q->merge_bvec_fn(q, &bvm, bvec) < bvec->bv_len) { + bvec->bv_page = NULL; + bvec->bv_len = 0; + bvec->bv_offset = 0; + return 0; + } + } + + /* If we may be able to merge these biovecs, force a recount */ + if (bio->bi_vcnt && (BIOVEC_PHYS_MERGEABLE(bvec-1, bvec))) + bio->bi_flags &= ~(1 << BIO_SEG_VALID); + + bio->bi_vcnt++; + bio->bi_phys_segments++; + done: + bio->bi_iter.bi_size += len; + return len; +} + +/** + * bio_add_pc_page - attempt to add page to bio + * @q: the target queue + * @bio: destination bio + * @page: page to add + * @len: vec entry length + * @offset: vec entry offset + * + * Attempt to add a page to the bio_vec maplist. This can fail for a + * number of reasons, such as the bio being full or target block device + * limitations. The target block device must allow bio's up to PAGE_SIZE, + * so it is always possible to add a single page to an empty bio. + * + * This should only be used by REQ_PC bios. + */ +int bio_add_pc_page(struct request_queue *q, struct bio *bio, struct page *page, + unsigned int len, unsigned int offset) +{ + return __bio_add_page(q, bio, page, len, offset, + queue_max_hw_sectors(q)); +} +EXPORT_SYMBOL(bio_add_pc_page); + +/** + * bio_add_page - attempt to add page to bio + * @bio: destination bio + * @page: page to add + * @len: vec entry length + * @offset: vec entry offset + * + * Attempt to add a page to the bio_vec maplist. This can fail for a + * number of reasons, such as the bio being full or target block device + * limitations. The target block device must allow bio's up to PAGE_SIZE, + * so it is always possible to add a single page to an empty bio. + */ +int bio_add_page(struct bio *bio, struct page *page, unsigned int len, + unsigned int offset) +{ + struct request_queue *q = bdev_get_queue(bio->bi_bdev); + unsigned int max_sectors; + + max_sectors = blk_max_size_offset(q, bio->bi_iter.bi_sector); + if ((max_sectors < (len >> 9)) && !bio->bi_iter.bi_size) + max_sectors = len >> 9; + + return __bio_add_page(q, bio, page, len, offset, max_sectors); +} +EXPORT_SYMBOL(bio_add_page); + +struct submit_bio_ret { + struct completion event; + int error; +}; + +static void submit_bio_wait_endio(struct bio *bio, int error) +{ + struct submit_bio_ret *ret = bio->bi_private; + + ret->error = error; + complete(&ret->event); +} + +/** + * submit_bio_wait - submit a bio, and wait until it completes + * @rw: whether to %READ or %WRITE, or maybe to %READA (read ahead) + * @bio: The &struct bio which describes the I/O + * + * Simple wrapper around submit_bio(). Returns 0 on success, or the error from + * bio_endio() on failure. + */ +int submit_bio_wait(int rw, struct bio *bio) +{ + struct submit_bio_ret ret; + + rw |= REQ_SYNC; + init_completion(&ret.event); + bio->bi_private = &ret; + bio->bi_end_io = submit_bio_wait_endio; + submit_bio(rw, bio); + wait_for_completion(&ret.event); + + return ret.error; +} +EXPORT_SYMBOL(submit_bio_wait); + +/** + * bio_advance - increment/complete a bio by some number of bytes + * @bio: bio to advance + * @bytes: number of bytes to complete + * + * This updates bi_sector, bi_size and bi_idx; if the number of bytes to + * complete doesn't align with a bvec boundary, then bv_len and bv_offset will + * be updated on the last bvec as well. + * + * @bio will then represent the remaining, uncompleted portion of the io. + */ +void bio_advance(struct bio *bio, unsigned bytes) +{ + if (bio_integrity(bio)) + bio_integrity_advance(bio, bytes); + + bio_advance_iter(bio, &bio->bi_iter, bytes); +} +EXPORT_SYMBOL(bio_advance); + +/** + * bio_alloc_pages - allocates a single page for each bvec in a bio + * @bio: bio to allocate pages for + * @gfp_mask: flags for allocation + * + * Allocates pages up to @bio->bi_vcnt. + * + * Returns 0 on success, -ENOMEM on failure. On failure, any allocated pages are + * freed. + */ +int bio_alloc_pages(struct bio *bio, gfp_t gfp_mask) +{ + int i; + struct bio_vec *bv; + + bio_for_each_segment_all(bv, bio, i) { + bv->bv_page = alloc_page(gfp_mask); + if (!bv->bv_page) { + while (--bv >= bio->bi_io_vec) + __free_page(bv->bv_page); + return -ENOMEM; + } + } + + return 0; +} +EXPORT_SYMBOL(bio_alloc_pages); + +/** + * bio_copy_data - copy contents of data buffers from one chain of bios to + * another + * @src: source bio list + * @dst: destination bio list + * + * If @src and @dst are single bios, bi_next must be NULL - otherwise, treats + * @src and @dst as linked lists of bios. + * + * Stops when it reaches the end of either @src or @dst - that is, copies + * min(src->bi_size, dst->bi_size) bytes (or the equivalent for lists of bios). + */ +void bio_copy_data(struct bio *dst, struct bio *src) +{ + struct bvec_iter src_iter, dst_iter; + struct bio_vec src_bv, dst_bv; + void *src_p, *dst_p; + unsigned bytes; + + src_iter = src->bi_iter; + dst_iter = dst->bi_iter; + + while (1) { + if (!src_iter.bi_size) { + src = src->bi_next; + if (!src) + break; + + src_iter = src->bi_iter; + } + + if (!dst_iter.bi_size) { + dst = dst->bi_next; + if (!dst) + break; + + dst_iter = dst->bi_iter; + } + + src_bv = bio_iter_iovec(src, src_iter); + dst_bv = bio_iter_iovec(dst, dst_iter); + + bytes = min(src_bv.bv_len, dst_bv.bv_len); + + src_p = kmap_atomic(src_bv.bv_page); + dst_p = kmap_atomic(dst_bv.bv_page); + + memcpy(dst_p + dst_bv.bv_offset, + src_p + src_bv.bv_offset, + bytes); + + kunmap_atomic(dst_p); + kunmap_atomic(src_p); + + bio_advance_iter(src, &src_iter, bytes); + bio_advance_iter(dst, &dst_iter, bytes); + } +} +EXPORT_SYMBOL(bio_copy_data); + +struct bio_map_data { + int nr_sgvecs; + int is_our_pages; + struct sg_iovec sgvecs[]; +}; + +static void bio_set_map_data(struct bio_map_data *bmd, struct bio *bio, + const struct sg_iovec *iov, int iov_count, + int is_our_pages) +{ + memcpy(bmd->sgvecs, iov, sizeof(struct sg_iovec) * iov_count); + bmd->nr_sgvecs = iov_count; + bmd->is_our_pages = is_our_pages; + bio->bi_private = bmd; +} + +static struct bio_map_data *bio_alloc_map_data(unsigned int iov_count, + gfp_t gfp_mask) +{ + if (iov_count > UIO_MAXIOV) + return NULL; + + return kmalloc(sizeof(struct bio_map_data) + + sizeof(struct sg_iovec) * iov_count, gfp_mask); +} + +static int __bio_copy_iov(struct bio *bio, const struct sg_iovec *iov, int iov_count, + int to_user, int from_user, int do_free_page) +{ + int ret = 0, i; + struct bio_vec *bvec; + int iov_idx = 0; + unsigned int iov_off = 0; + + bio_for_each_segment_all(bvec, bio, i) { + char *bv_addr = page_address(bvec->bv_page); + unsigned int bv_len = bvec->bv_len; + + while (bv_len && iov_idx < iov_count) { + unsigned int bytes; + char __user *iov_addr; + + bytes = min_t(unsigned int, + iov[iov_idx].iov_len - iov_off, bv_len); + iov_addr = iov[iov_idx].iov_base + iov_off; + + if (!ret) { + if (to_user) + ret = copy_to_user(iov_addr, bv_addr, + bytes); + + if (from_user) + ret = copy_from_user(bv_addr, iov_addr, + bytes); + + if (ret) + ret = -EFAULT; + } + + bv_len -= bytes; + bv_addr += bytes; + iov_addr += bytes; + iov_off += bytes; + + if (iov[iov_idx].iov_len == iov_off) { + iov_idx++; + iov_off = 0; + } + } + + if (do_free_page) + __free_page(bvec->bv_page); + } + + return ret; +} + +/** + * bio_uncopy_user - finish previously mapped bio + * @bio: bio being terminated + * + * Free pages allocated from bio_copy_user() and write back data + * to user space in case of a read. + */ +int bio_uncopy_user(struct bio *bio) +{ + struct bio_map_data *bmd = bio->bi_private; + struct bio_vec *bvec; + int ret = 0, i; + + if (!bio_flagged(bio, BIO_NULL_MAPPED)) { + /* + * if we're in a workqueue, the request is orphaned, so + * don't copy into a random user address space, just free. + */ + if (current->mm) + ret = __bio_copy_iov(bio, bmd->sgvecs, bmd->nr_sgvecs, + bio_data_dir(bio) == READ, + 0, bmd->is_our_pages); + else if (bmd->is_our_pages) + bio_for_each_segment_all(bvec, bio, i) + __free_page(bvec->bv_page); + } + kfree(bmd); + bio_put(bio); + return ret; +} +EXPORT_SYMBOL(bio_uncopy_user); + +/** + * bio_copy_user_iov - copy user data to bio + * @q: destination block queue + * @map_data: pointer to the rq_map_data holding pages (if necessary) + * @iov: the iovec. + * @iov_count: number of elements in the iovec + * @write_to_vm: bool indicating writing to pages or not + * @gfp_mask: memory allocation flags + * + * Prepares and returns a bio for indirect user io, bouncing data + * to/from kernel pages as necessary. Must be paired with + * call bio_uncopy_user() on io completion. + */ +struct bio *bio_copy_user_iov(struct request_queue *q, + struct rq_map_data *map_data, + const struct sg_iovec *iov, int iov_count, + int write_to_vm, gfp_t gfp_mask) +{ + struct bio_map_data *bmd; + struct bio_vec *bvec; + struct page *page; + struct bio *bio; + int i, ret; + int nr_pages = 0; + unsigned int len = 0; + unsigned int offset = map_data ? map_data->offset & ~PAGE_MASK : 0; + + for (i = 0; i < iov_count; i++) { + unsigned long uaddr; + unsigned long end; + unsigned long start; + + uaddr = (unsigned long)iov[i].iov_base; + end = (uaddr + iov[i].iov_len + PAGE_SIZE - 1) >> PAGE_SHIFT; + start = uaddr >> PAGE_SHIFT; + + /* + * Overflow, abort + */ + if (end < start) + return ERR_PTR(-EINVAL); + + nr_pages += end - start; + len += iov[i].iov_len; + } + + if (offset) + nr_pages++; + + bmd = bio_alloc_map_data(iov_count, gfp_mask); + if (!bmd) + return ERR_PTR(-ENOMEM); + + ret = -ENOMEM; + bio = bio_kmalloc(gfp_mask, nr_pages); + if (!bio) + goto out_bmd; + + if (!write_to_vm) + bio->bi_rw |= REQ_WRITE; + + ret = 0; + + if (map_data) { + nr_pages = 1 << map_data->page_order; + i = map_data->offset / PAGE_SIZE; + } + while (len) { + unsigned int bytes = PAGE_SIZE; + + bytes -= offset; + + if (bytes > len) + bytes = len; + + if (map_data) { + if (i == map_data->nr_entries * nr_pages) { + ret = -ENOMEM; + break; + } + + page = map_data->pages[i / nr_pages]; + page += (i % nr_pages); + + i++; + } else { + page = alloc_page(q->bounce_gfp | gfp_mask); + if (!page) { + ret = -ENOMEM; + break; + } + } + + if (bio_add_pc_page(q, bio, page, bytes, offset) < bytes) + break; + + len -= bytes; + offset = 0; + } + + if (ret) + goto cleanup; + + /* + * success + */ + if ((!write_to_vm && (!map_data || !map_data->null_mapped)) || + (map_data && map_data->from_user)) { + ret = __bio_copy_iov(bio, iov, iov_count, 0, 1, 0); + if (ret) + goto cleanup; + } + + bio_set_map_data(bmd, bio, iov, iov_count, map_data ? 0 : 1); + return bio; +cleanup: + if (!map_data) + bio_for_each_segment_all(bvec, bio, i) + __free_page(bvec->bv_page); + + bio_put(bio); +out_bmd: + kfree(bmd); + return ERR_PTR(ret); +} + +/** + * bio_copy_user - copy user data to bio + * @q: destination block queue + * @map_data: pointer to the rq_map_data holding pages (if necessary) + * @uaddr: start of user address + * @len: length in bytes + * @write_to_vm: bool indicating writing to pages or not + * @gfp_mask: memory allocation flags + * + * Prepares and returns a bio for indirect user io, bouncing data + * to/from kernel pages as necessary. Must be paired with + * call bio_uncopy_user() on io completion. + */ +struct bio *bio_copy_user(struct request_queue *q, struct rq_map_data *map_data, + unsigned long uaddr, unsigned int len, + int write_to_vm, gfp_t gfp_mask) +{ + struct sg_iovec iov; + + iov.iov_base = (void __user *)uaddr; + iov.iov_len = len; + + return bio_copy_user_iov(q, map_data, &iov, 1, write_to_vm, gfp_mask); +} +EXPORT_SYMBOL(bio_copy_user); + +static struct bio *__bio_map_user_iov(struct request_queue *q, + struct block_device *bdev, + const struct sg_iovec *iov, int iov_count, + int write_to_vm, gfp_t gfp_mask) +{ + int i, j; + int nr_pages = 0; + struct page **pages; + struct bio *bio; + int cur_page = 0; + int ret, offset; + + for (i = 0; i < iov_count; i++) { + unsigned long uaddr = (unsigned long)iov[i].iov_base; + unsigned long len = iov[i].iov_len; + unsigned long end = (uaddr + len + PAGE_SIZE - 1) >> PAGE_SHIFT; + unsigned long start = uaddr >> PAGE_SHIFT; + + /* + * Overflow, abort + */ + if (end < start) + return ERR_PTR(-EINVAL); + + nr_pages += end - start; + /* + * buffer must be aligned to at least hardsector size for now + */ + if (uaddr & queue_dma_alignment(q)) + return ERR_PTR(-EINVAL); + } + + if (!nr_pages) + return ERR_PTR(-EINVAL); + + bio = bio_kmalloc(gfp_mask, nr_pages); + if (!bio) + return ERR_PTR(-ENOMEM); + + ret = -ENOMEM; + pages = kcalloc(nr_pages, sizeof(struct page *), gfp_mask); + if (!pages) + goto out; + + for (i = 0; i < iov_count; i++) { + unsigned long uaddr = (unsigned long)iov[i].iov_base; + unsigned long len = iov[i].iov_len; + unsigned long end = (uaddr + len + PAGE_SIZE - 1) >> PAGE_SHIFT; + unsigned long start = uaddr >> PAGE_SHIFT; + const int local_nr_pages = end - start; + const int page_limit = cur_page + local_nr_pages; + + ret = get_user_pages_fast(uaddr, local_nr_pages, + write_to_vm, &pages[cur_page]); + if (ret < local_nr_pages) { + ret = -EFAULT; + goto out_unmap; + } + + offset = uaddr & ~PAGE_MASK; + for (j = cur_page; j < page_limit; j++) { + unsigned int bytes = PAGE_SIZE - offset; + + if (len <= 0) + break; + + if (bytes > len) + bytes = len; + + /* + * sorry... + */ + if (bio_add_pc_page(q, bio, pages[j], bytes, offset) < + bytes) + break; + + len -= bytes; + offset = 0; + } + + cur_page = j; + /* + * release the pages we didn't map into the bio, if any + */ + while (j < page_limit) + page_cache_release(pages[j++]); + } + + kfree(pages); + + /* + * set data direction, and check if mapped pages need bouncing + */ + if (!write_to_vm) + bio->bi_rw |= REQ_WRITE; + + bio->bi_bdev = bdev; + bio->bi_flags |= (1 << BIO_USER_MAPPED); + return bio; + + out_unmap: + for (i = 0; i < nr_pages; i++) { + if(!pages[i]) + break; + page_cache_release(pages[i]); + } + out: + kfree(pages); + bio_put(bio); + return ERR_PTR(ret); +} + +/** + * bio_map_user - map user address into bio + * @q: the struct request_queue for the bio + * @bdev: destination block device + * @uaddr: start of user address + * @len: length in bytes + * @write_to_vm: bool indicating writing to pages or not + * @gfp_mask: memory allocation flags + * + * Map the user space address into a bio suitable for io to a block + * device. Returns an error pointer in case of error. + */ +struct bio *bio_map_user(struct request_queue *q, struct block_device *bdev, + unsigned long uaddr, unsigned int len, int write_to_vm, + gfp_t gfp_mask) +{ + struct sg_iovec iov; + + iov.iov_base = (void __user *)uaddr; + iov.iov_len = len; + + return bio_map_user_iov(q, bdev, &iov, 1, write_to_vm, gfp_mask); +} +EXPORT_SYMBOL(bio_map_user); + +/** + * bio_map_user_iov - map user sg_iovec table into bio + * @q: the struct request_queue for the bio + * @bdev: destination block device + * @iov: the iovec. + * @iov_count: number of elements in the iovec + * @write_to_vm: bool indicating writing to pages or not + * @gfp_mask: memory allocation flags + * + * Map the user space address into a bio suitable for io to a block + * device. Returns an error pointer in case of error. + */ +struct bio *bio_map_user_iov(struct request_queue *q, struct block_device *bdev, + const struct sg_iovec *iov, int iov_count, + int write_to_vm, gfp_t gfp_mask) +{ + struct bio *bio; + + bio = __bio_map_user_iov(q, bdev, iov, iov_count, write_to_vm, + gfp_mask); + if (IS_ERR(bio)) + return bio; + + /* + * subtle -- if __bio_map_user() ended up bouncing a bio, + * it would normally disappear when its bi_end_io is run. + * however, we need it for the unmap, so grab an extra + * reference to it + */ + bio_get(bio); + + return bio; +} + +static void __bio_unmap_user(struct bio *bio) +{ + struct bio_vec *bvec; + int i; + + /* + * make sure we dirty pages we wrote to + */ + bio_for_each_segment_all(bvec, bio, i) { + if (bio_data_dir(bio) == READ) + set_page_dirty_lock(bvec->bv_page); + + page_cache_release(bvec->bv_page); + } + + bio_put(bio); +} + +/** + * bio_unmap_user - unmap a bio + * @bio: the bio being unmapped + * + * Unmap a bio previously mapped by bio_map_user(). Must be called with + * a process context. + * + * bio_unmap_user() may sleep. + */ +void bio_unmap_user(struct bio *bio) +{ + __bio_unmap_user(bio); + bio_put(bio); +} +EXPORT_SYMBOL(bio_unmap_user); + +static void bio_map_kern_endio(struct bio *bio, int err) +{ + bio_put(bio); +} + +static struct bio *__bio_map_kern(struct request_queue *q, void *data, + unsigned int len, gfp_t gfp_mask) +{ + unsigned long kaddr = (unsigned long)data; + unsigned long end = (kaddr + len + PAGE_SIZE - 1) >> PAGE_SHIFT; + unsigned long start = kaddr >> PAGE_SHIFT; + const int nr_pages = end - start; + int offset, i; + struct bio *bio; + + bio = bio_kmalloc(gfp_mask, nr_pages); + if (!bio) + return ERR_PTR(-ENOMEM); + + offset = offset_in_page(kaddr); + for (i = 0; i < nr_pages; i++) { + unsigned int bytes = PAGE_SIZE - offset; + + if (len <= 0) + break; + + if (bytes > len) + bytes = len; + + if (bio_add_pc_page(q, bio, virt_to_page(data), bytes, + offset) < bytes) + break; + + data += bytes; + len -= bytes; + offset = 0; + } + + bio->bi_end_io = bio_map_kern_endio; + return bio; +} + +/** + * bio_map_kern - map kernel address into bio + * @q: the struct request_queue for the bio + * @data: pointer to buffer to map + * @len: length in bytes + * @gfp_mask: allocation flags for bio allocation + * + * Map the kernel address into a bio suitable for io to a block + * device. Returns an error pointer in case of error. + */ +struct bio *bio_map_kern(struct request_queue *q, void *data, unsigned int len, + gfp_t gfp_mask) +{ + struct bio *bio; + + bio = __bio_map_kern(q, data, len, gfp_mask); + if (IS_ERR(bio)) + return bio; + + if (bio->bi_iter.bi_size == len) + return bio; + + /* + * Don't support partial mappings. + */ + bio_put(bio); + return ERR_PTR(-EINVAL); +} +EXPORT_SYMBOL(bio_map_kern); + +static void bio_copy_kern_endio(struct bio *bio, int err) +{ + struct bio_vec *bvec; + const int read = bio_data_dir(bio) == READ; + struct bio_map_data *bmd = bio->bi_private; + int i; + char *p = bmd->sgvecs[0].iov_base; + + bio_for_each_segment_all(bvec, bio, i) { + char *addr = page_address(bvec->bv_page); + + if (read) + memcpy(p, addr, bvec->bv_len); + + __free_page(bvec->bv_page); + p += bvec->bv_len; + } + + kfree(bmd); + bio_put(bio); +} + +/** + * bio_copy_kern - copy kernel address into bio + * @q: the struct request_queue for the bio + * @data: pointer to buffer to copy + * @len: length in bytes + * @gfp_mask: allocation flags for bio and page allocation + * @reading: data direction is READ + * + * copy the kernel address into a bio suitable for io to a block + * device. Returns an error pointer in case of error. + */ +struct bio *bio_copy_kern(struct request_queue *q, void *data, unsigned int len, + gfp_t gfp_mask, int reading) +{ + struct bio *bio; + struct bio_vec *bvec; + int i; + + bio = bio_copy_user(q, NULL, (unsigned long)data, len, 1, gfp_mask); + if (IS_ERR(bio)) + return bio; + + if (!reading) { + void *p = data; + + bio_for_each_segment_all(bvec, bio, i) { + char *addr = page_address(bvec->bv_page); + + memcpy(addr, p, bvec->bv_len); + p += bvec->bv_len; + } + } + + bio->bi_end_io = bio_copy_kern_endio; + + return bio; +} +EXPORT_SYMBOL(bio_copy_kern); + +/* + * bio_set_pages_dirty() and bio_check_pages_dirty() are support functions + * for performing direct-IO in BIOs. + * + * The problem is that we cannot run set_page_dirty() from interrupt context + * because the required locks are not interrupt-safe. So what we can do is to + * mark the pages dirty _before_ performing IO. And in interrupt context, + * check that the pages are still dirty. If so, fine. If not, redirty them + * in process context. + * + * We special-case compound pages here: normally this means reads into hugetlb + * pages. The logic in here doesn't really work right for compound pages + * because the VM does not uniformly chase down the head page in all cases. + * But dirtiness of compound pages is pretty meaningless anyway: the VM doesn't + * handle them at all. So we skip compound pages here at an early stage. + * + * Note that this code is very hard to test under normal circumstances because + * direct-io pins the pages with get_user_pages(). This makes + * is_page_cache_freeable return false, and the VM will not clean the pages. + * But other code (eg, flusher threads) could clean the pages if they are mapped + * pagecache. + * + * Simply disabling the call to bio_set_pages_dirty() is a good way to test the + * deferred bio dirtying paths. + */ + +/* + * bio_set_pages_dirty() will mark all the bio's pages as dirty. + */ +void bio_set_pages_dirty(struct bio *bio) +{ + struct bio_vec *bvec; + int i; + + bio_for_each_segment_all(bvec, bio, i) { + struct page *page = bvec->bv_page; + + if (page && !PageCompound(page)) + set_page_dirty_lock(page); + } +} + +static void bio_release_pages(struct bio *bio) +{ + struct bio_vec *bvec; + int i; + + bio_for_each_segment_all(bvec, bio, i) { + struct page *page = bvec->bv_page; + + if (page) + put_page(page); + } +} + +/* + * bio_check_pages_dirty() will check that all the BIO's pages are still dirty. + * If they are, then fine. If, however, some pages are clean then they must + * have been written out during the direct-IO read. So we take another ref on + * the BIO and the offending pages and re-dirty the pages in process context. + * + * It is expected that bio_check_pages_dirty() will wholly own the BIO from + * here on. It will run one page_cache_release() against each page and will + * run one bio_put() against the BIO. + */ + +static void bio_dirty_fn(struct work_struct *work); + +static DECLARE_WORK(bio_dirty_work, bio_dirty_fn); +static DEFINE_SPINLOCK(bio_dirty_lock); +static struct bio *bio_dirty_list; + +/* + * This runs in process context + */ +static void bio_dirty_fn(struct work_struct *work) +{ + unsigned long flags; + struct bio *bio; + + spin_lock_irqsave(&bio_dirty_lock, flags); + bio = bio_dirty_list; + bio_dirty_list = NULL; + spin_unlock_irqrestore(&bio_dirty_lock, flags); + + while (bio) { + struct bio *next = bio->bi_private; + + bio_set_pages_dirty(bio); + bio_release_pages(bio); + bio_put(bio); + bio = next; + } +} + +void bio_check_pages_dirty(struct bio *bio) +{ + struct bio_vec *bvec; + int nr_clean_pages = 0; + int i; + + bio_for_each_segment_all(bvec, bio, i) { + struct page *page = bvec->bv_page; + + if (PageDirty(page) || PageCompound(page)) { + page_cache_release(page); + bvec->bv_page = NULL; + } else { + nr_clean_pages++; + } + } + + if (nr_clean_pages) { + unsigned long flags; + + spin_lock_irqsave(&bio_dirty_lock, flags); + bio->bi_private = bio_dirty_list; + bio_dirty_list = bio; + spin_unlock_irqrestore(&bio_dirty_lock, flags); + schedule_work(&bio_dirty_work); + } else { + bio_put(bio); + } +} + +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE +void bio_flush_dcache_pages(struct bio *bi) +{ + struct bio_vec bvec; + struct bvec_iter iter; + + bio_for_each_segment(bvec, bi, iter) + flush_dcache_page(bvec.bv_page); +} +EXPORT_SYMBOL(bio_flush_dcache_pages); +#endif + +/** + * bio_endio - end I/O on a bio + * @bio: bio + * @error: error, if any + * + * Description: + * bio_endio() will end I/O on the whole bio. bio_endio() is the + * preferred way to end I/O on a bio, it takes care of clearing + * BIO_UPTODATE on error. @error is 0 on success, and and one of the + * established -Exxxx (-EIO, for instance) error values in case + * something went wrong. No one should call bi_end_io() directly on a + * bio unless they own it and thus know that it has an end_io + * function. + **/ +void bio_endio(struct bio *bio, int error) +{ + while (bio) { + BUG_ON(atomic_read(&bio->bi_remaining) <= 0); + + if (error) + clear_bit(BIO_UPTODATE, &bio->bi_flags); + else if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) + error = -EIO; + + if (!atomic_dec_and_test(&bio->bi_remaining)) + return; + + /* + * Need to have a real endio function for chained bios, + * otherwise various corner cases will break (like stacking + * block devices that save/restore bi_end_io) - however, we want + * to avoid unbounded recursion and blowing the stack. Tail call + * optimization would handle this, but compiling with frame + * pointers also disables gcc's sibling call optimization. + */ + if (bio->bi_end_io == bio_chain_endio) { + struct bio *parent = bio->bi_private; + bio_put(bio); + bio = parent; + } else { + if (bio->bi_end_io) + bio->bi_end_io(bio, error); + bio = NULL; + } + } +} +EXPORT_SYMBOL(bio_endio); + +/** + * bio_endio_nodec - end I/O on a bio, without decrementing bi_remaining + * @bio: bio + * @error: error, if any + * + * For code that has saved and restored bi_end_io; thing hard before using this + * function, probably you should've cloned the entire bio. + **/ +void bio_endio_nodec(struct bio *bio, int error) +{ + atomic_inc(&bio->bi_remaining); + bio_endio(bio, error); +} +EXPORT_SYMBOL(bio_endio_nodec); + +/** + * bio_split - split a bio + * @bio: bio to split + * @sectors: number of sectors to split from the front of @bio + * @gfp: gfp mask + * @bs: bio set to allocate from + * + * Allocates and returns a new bio which represents @sectors from the start of + * @bio, and updates @bio to represent the remaining sectors. + * + * The newly allocated bio will point to @bio's bi_io_vec; it is the caller's + * responsibility to ensure that @bio is not freed before the split. + */ +struct bio *bio_split(struct bio *bio, int sectors, + gfp_t gfp, struct bio_set *bs) +{ + struct bio *split = NULL; + + BUG_ON(sectors <= 0); + BUG_ON(sectors >= bio_sectors(bio)); + + split = bio_clone_fast(bio, gfp, bs); + if (!split) + return NULL; + + split->bi_iter.bi_size = sectors << 9; + + if (bio_integrity(split)) + bio_integrity_trim(split, 0, sectors); + + bio_advance(bio, split->bi_iter.bi_size); + + return split; +} +EXPORT_SYMBOL(bio_split); + +/** + * bio_trim - trim a bio + * @bio: bio to trim + * @offset: number of sectors to trim from the front of @bio + * @size: size we want to trim @bio to, in sectors + */ +void bio_trim(struct bio *bio, int offset, int size) +{ + /* 'bio' is a cloned bio which we need to trim to match + * the given offset and size. + */ + + size <<= 9; + if (offset == 0 && size == bio->bi_iter.bi_size) + return; + + clear_bit(BIO_SEG_VALID, &bio->bi_flags); + + bio_advance(bio, offset << 9); + + bio->bi_iter.bi_size = size; +} +EXPORT_SYMBOL_GPL(bio_trim); + +/* + * create memory pools for biovec's in a bio_set. + * use the global biovec slabs created for general use. + */ +mempool_t *biovec_create_pool(int pool_entries) +{ + struct biovec_slab *bp = bvec_slabs + BIOVEC_MAX_IDX; + + return mempool_create_slab_pool(pool_entries, bp->slab); +} + +void bioset_free(struct bio_set *bs) +{ + if (bs->rescue_workqueue) + destroy_workqueue(bs->rescue_workqueue); + + if (bs->bio_pool) + mempool_destroy(bs->bio_pool); + + if (bs->bvec_pool) + mempool_destroy(bs->bvec_pool); + + bioset_integrity_free(bs); + bio_put_slab(bs); + + kfree(bs); +} +EXPORT_SYMBOL(bioset_free); + +/** + * bioset_create - Create a bio_set + * @pool_size: Number of bio and bio_vecs to cache in the mempool + * @front_pad: Number of bytes to allocate in front of the returned bio + * + * Description: + * Set up a bio_set to be used with @bio_alloc_bioset. Allows the caller + * to ask for a number of bytes to be allocated in front of the bio. + * Front pad allocation is useful for embedding the bio inside + * another structure, to avoid allocating extra data to go with the bio. + * Note that the bio must be embedded at the END of that structure always, + * or things will break badly. + */ +struct bio_set *bioset_create(unsigned int pool_size, unsigned int front_pad) +{ + unsigned int back_pad = BIO_INLINE_VECS * sizeof(struct bio_vec); + struct bio_set *bs; + + bs = kzalloc(sizeof(*bs), GFP_KERNEL); + if (!bs) + return NULL; + + bs->front_pad = front_pad; + + spin_lock_init(&bs->rescue_lock); + bio_list_init(&bs->rescue_list); + INIT_WORK(&bs->rescue_work, bio_alloc_rescue); + + bs->bio_slab = bio_find_or_create_slab(front_pad + back_pad); + if (!bs->bio_slab) { + kfree(bs); + return NULL; + } + + bs->bio_pool = mempool_create_slab_pool(pool_size, bs->bio_slab); + if (!bs->bio_pool) + goto bad; + + bs->bvec_pool = biovec_create_pool(pool_size); + if (!bs->bvec_pool) + goto bad; + + bs->rescue_workqueue = alloc_workqueue("bioset", WQ_MEM_RECLAIM, 0); + if (!bs->rescue_workqueue) + goto bad; + + return bs; +bad: + bioset_free(bs); + return NULL; +} +EXPORT_SYMBOL(bioset_create); + +#ifdef CONFIG_BLK_CGROUP +/** + * bio_associate_current - associate a bio with %current + * @bio: target bio + * + * Associate @bio with %current if it hasn't been associated yet. Block + * layer will treat @bio as if it were issued by %current no matter which + * task actually issues it. + * + * This function takes an extra reference of @task's io_context and blkcg + * which will be put when @bio is released. The caller must own @bio, + * ensure %current->io_context exists, and is responsible for synchronizing + * calls to this function. + */ +int bio_associate_current(struct bio *bio) +{ + struct io_context *ioc; + struct cgroup_subsys_state *css; + + if (bio->bi_ioc) + return -EBUSY; + + ioc = current->io_context; + if (!ioc) + return -ENOENT; + + /* acquire active ref on @ioc and associate */ + get_io_context_active(ioc); + bio->bi_ioc = ioc; + + /* associate blkcg if exists */ + rcu_read_lock(); + css = task_css(current, blkio_cgrp_id); + if (css && css_tryget_online(css)) + bio->bi_css = css; + rcu_read_unlock(); + + return 0; +} + +/** + * bio_disassociate_task - undo bio_associate_current() + * @bio: target bio + */ +void bio_disassociate_task(struct bio *bio) +{ + if (bio->bi_ioc) { + put_io_context(bio->bi_ioc); + bio->bi_ioc = NULL; + } + if (bio->bi_css) { + css_put(bio->bi_css); + bio->bi_css = NULL; + } +} + +#endif /* CONFIG_BLK_CGROUP */ + +static void __init biovec_init_slabs(void) +{ + int i; + + for (i = 0; i < BIOVEC_NR_POOLS; i++) { + int size; + struct biovec_slab *bvs = bvec_slabs + i; + + if (bvs->nr_vecs <= BIO_INLINE_VECS) { + bvs->slab = NULL; + continue; + } + + size = bvs->nr_vecs * sizeof(struct bio_vec); + bvs->slab = kmem_cache_create(bvs->name, size, 0, + SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); + } +} + +static int __init init_bio(void) +{ + bio_slab_max = 2; + bio_slab_nr = 0; + bio_slabs = kzalloc(bio_slab_max * sizeof(struct bio_slab), GFP_KERNEL); + if (!bio_slabs) + panic("bio: can't allocate bios\n"); + + bio_integrity_init(); + biovec_init_slabs(); + + fs_bio_set = bioset_create(BIO_POOL_SIZE, 0); + if (!fs_bio_set) + panic("bio: can't allocate bios\n"); + + if (bioset_integrity_create(fs_bio_set, BIO_POOL_SIZE)) + panic("bio: can't create integrity pool\n"); + + return 0; +} +subsys_initcall(init_bio); diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index e90c7c164c8..28d227c5ca7 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -80,7 +80,7 @@ static struct blkcg_gq *blkg_alloc(struct blkcg *blkcg, struct request_queue *q, blkg->q = q; INIT_LIST_HEAD(&blkg->q_node); blkg->blkcg = blkcg; - blkg->refcnt = 1; + atomic_set(&blkg->refcnt, 1); /* root blkg uses @q->root_rl, init rl only for !root blkgs */ if (blkcg != &blkcg_root) { @@ -185,7 +185,7 @@ static struct blkcg_gq *blkg_create(struct blkcg *blkcg, lockdep_assert_held(q->queue_lock); /* blkg holds a reference to blkcg */ - if (!css_tryget(&blkcg->css)) { + if (!css_tryget_online(&blkcg->css)) { ret = -EINVAL; goto err_free_blkg; } @@ -235,8 +235,13 @@ static struct blkcg_gq *blkg_create(struct blkcg *blkcg, blkg->online = true; spin_unlock(&blkcg->lock); - if (!ret) + if (!ret) { + if (blkcg == &blkcg_root) { + q->root_blkg = blkg; + q->root_rl.blkg = blkg; + } return blkg; + } /* @blkg failed fully initialized, use the usual release path */ blkg_put(blkg); @@ -331,10 +336,19 @@ static void blkg_destroy(struct blkcg_gq *blkg) * under queue_lock. If it's not pointing to @blkg now, it never * will. Hint assignment itself can race safely. */ - if (rcu_dereference_raw(blkcg->blkg_hint) == blkg) + if (rcu_access_pointer(blkcg->blkg_hint) == blkg) rcu_assign_pointer(blkcg->blkg_hint, NULL); /* + * If root blkg is destroyed. Just clear the pointer since root_rl + * does not take reference on root blkg. + */ + if (blkcg == &blkcg_root) { + blkg->q->root_blkg = NULL; + blkg->q->root_rl.blkg = NULL; + } + + /* * Put the reference taken at the time of creation so that when all * queues are gone, group can be destroyed. */ @@ -360,13 +374,6 @@ static void blkg_destroy_all(struct request_queue *q) blkg_destroy(blkg); spin_unlock(&blkcg->lock); } - - /* - * root blkg is destroyed. Just clear the pointer since - * root_rl does not take reference on root blkg. - */ - q->root_blkg = NULL; - q->root_rl.blkg = NULL; } /* @@ -392,11 +399,8 @@ void __blkg_release_rcu(struct rcu_head *rcu_head) /* release the blkcg and parent blkg refs this blkg has been holding */ css_put(&blkg->blkcg->css); - if (blkg->parent) { - spin_lock_irq(blkg->q->queue_lock); + if (blkg->parent) blkg_put(blkg->parent); - spin_unlock_irq(blkg->q->queue_lock); - } blkg_free(blkg); } @@ -444,7 +448,20 @@ static int blkcg_reset_stats(struct cgroup_subsys_state *css, struct blkcg_gq *blkg; int i; - mutex_lock(&blkcg_pol_mutex); + /* + * XXX: We invoke cgroup_add/rm_cftypes() under blkcg_pol_mutex + * which ends up putting cgroup's internal cgroup_tree_mutex under + * it; however, cgroup_tree_mutex is nested above cgroup file + * active protection and grabbing blkcg_pol_mutex from a cgroup + * file operation creates a possible circular dependency. cgroup + * internal locking is planned to go through further simplification + * and this issue should go away soon. For now, let's trylock + * blkcg_pol_mutex and restart the write on failure. + * + * http://lkml.kernel.org/g/5363C04B.4010400@oracle.com + */ + if (!mutex_trylock(&blkcg_pol_mutex)) + return restart_syscall(); spin_lock_irq(&blkcg->lock); /* @@ -855,6 +872,13 @@ void blkcg_drain_queue(struct request_queue *q) { lockdep_assert_held(q->queue_lock); + /* + * @q could be exiting and already have destroyed all blkgs as + * indicated by NULL root_blkg. If so, don't confuse policies. + */ + if (!q->root_blkg) + return; + blk_throtl_drain(q); } @@ -887,7 +911,7 @@ static int blkcg_can_attach(struct cgroup_subsys_state *css, int ret = 0; /* task_lock() is needed to avoid races with exit_io_context() */ - cgroup_taskset_for_each(task, css, tset) { + cgroup_taskset_for_each(task, tset) { task_lock(task); ioc = task->io_context; if (ioc && atomic_read(&ioc->nr_tasks) > 1) @@ -899,17 +923,14 @@ static int blkcg_can_attach(struct cgroup_subsys_state *css, return ret; } -struct cgroup_subsys blkio_subsys = { - .name = "blkio", +struct cgroup_subsys blkio_cgrp_subsys = { .css_alloc = blkcg_css_alloc, .css_offline = blkcg_css_offline, .css_free = blkcg_css_free, .can_attach = blkcg_can_attach, - .subsys_id = blkio_subsys_id, .base_cftypes = blkcg_files, - .module = THIS_MODULE, }; -EXPORT_SYMBOL_GPL(blkio_subsys); +EXPORT_SYMBOL_GPL(blkio_cgrp_subsys); /** * blkcg_activate_policy - activate a blkcg policy on a request_queue @@ -970,8 +991,6 @@ int blkcg_activate_policy(struct request_queue *q, ret = PTR_ERR(blkg); goto out_unlock; } - q->root_blkg = blkg; - q->root_rl.blkg = blkg; list_for_each_entry(blkg, &q->blkg_list, q_node) cnt++; @@ -1101,7 +1120,7 @@ int blkcg_policy_register(struct blkcg_policy *pol) /* everything is in place, add intf files for the new policy */ if (pol->cftypes) - WARN_ON(cgroup_add_cftypes(&blkio_subsys, pol->cftypes)); + WARN_ON(cgroup_add_cftypes(&blkio_cgrp_subsys, pol->cftypes)); ret = 0; out_unlock: mutex_unlock(&blkcg_pol_mutex); diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h index ae6969a7ffd..d3fd7aa3d2a 100644 --- a/block/blk-cgroup.h +++ b/block/blk-cgroup.h @@ -18,6 +18,7 @@ #include <linux/seq_file.h> #include <linux/radix-tree.h> #include <linux/blkdev.h> +#include <linux/atomic.h> /* Max limits for throttle policy */ #define THROTL_IOPS_MAX UINT_MAX @@ -104,7 +105,7 @@ struct blkcg_gq { struct request_list rl; /* reference count */ - int refcnt; + atomic_t refcnt; /* is this blkg online? protected by both blkcg and q locks */ bool online; @@ -186,7 +187,7 @@ static inline struct blkcg *css_to_blkcg(struct cgroup_subsys_state *css) static inline struct blkcg *task_blkcg(struct task_struct *tsk) { - return css_to_blkcg(task_css(tsk, blkio_subsys_id)); + return css_to_blkcg(task_css(tsk, blkio_cgrp_id)); } static inline struct blkcg *bio_blkcg(struct bio *bio) @@ -204,7 +205,7 @@ static inline struct blkcg *bio_blkcg(struct bio *bio) */ static inline struct blkcg *blkcg_parent(struct blkcg *blkcg) { - return css_to_blkcg(css_parent(&blkcg->css)); + return css_to_blkcg(blkcg->css.parent); } /** @@ -241,25 +242,28 @@ static inline struct blkcg_gq *pd_to_blkg(struct blkg_policy_data *pd) */ static inline int blkg_path(struct blkcg_gq *blkg, char *buf, int buflen) { - int ret; + char *p; - ret = cgroup_path(blkg->blkcg->css.cgroup, buf, buflen); - if (ret) + p = cgroup_path(blkg->blkcg->css.cgroup, buf, buflen); + if (!p) { strncpy(buf, "<unavailable>", buflen); - return ret; + return -ENAMETOOLONG; + } + + memmove(buf, p, buf + buflen - p); + return 0; } /** * blkg_get - get a blkg reference * @blkg: blkg to get * - * The caller should be holding queue_lock and an existing reference. + * The caller should be holding an existing reference. */ static inline void blkg_get(struct blkcg_gq *blkg) { - lockdep_assert_held(blkg->q->queue_lock); - WARN_ON_ONCE(!blkg->refcnt); - blkg->refcnt++; + WARN_ON_ONCE(atomic_read(&blkg->refcnt) <= 0); + atomic_inc(&blkg->refcnt); } void __blkg_release_rcu(struct rcu_head *rcu); @@ -267,14 +271,11 @@ void __blkg_release_rcu(struct rcu_head *rcu); /** * blkg_put - put a blkg reference * @blkg: blkg to put - * - * The caller should be holding queue_lock. */ static inline void blkg_put(struct blkcg_gq *blkg) { - lockdep_assert_held(blkg->q->queue_lock); - WARN_ON_ONCE(blkg->refcnt <= 0); - if (!--blkg->refcnt) + WARN_ON_ONCE(atomic_read(&blkg->refcnt) <= 0); + if (atomic_dec_and_test(&blkg->refcnt)) call_rcu(&blkg->rcu_head, __blkg_release_rcu); } @@ -402,6 +403,11 @@ struct request_list *__blk_queue_next_rl(struct request_list *rl, #define blk_queue_for_each_rl(rl, q) \ for ((rl) = &(q)->root_rl; (rl); (rl) = __blk_queue_next_rl((rl), (q))) +static inline void blkg_stat_init(struct blkg_stat *stat) +{ + u64_stats_init(&stat->syncp); +} + /** * blkg_stat_add - add a value to a blkg_stat * @stat: target blkg_stat @@ -430,9 +436,9 @@ static inline uint64_t blkg_stat_read(struct blkg_stat *stat) uint64_t v; do { - start = u64_stats_fetch_begin(&stat->syncp); + start = u64_stats_fetch_begin_irq(&stat->syncp); v = stat->cnt; - } while (u64_stats_fetch_retry(&stat->syncp, start)); + } while (u64_stats_fetch_retry_irq(&stat->syncp, start)); return v; } @@ -458,6 +464,11 @@ static inline void blkg_stat_merge(struct blkg_stat *to, struct blkg_stat *from) blkg_stat_add(to, blkg_stat_read(from)); } +static inline void blkg_rwstat_init(struct blkg_rwstat *rwstat) +{ + u64_stats_init(&rwstat->syncp); +} + /** * blkg_rwstat_add - add a value to a blkg_rwstat * @rwstat: target blkg_rwstat @@ -498,9 +509,9 @@ static inline struct blkg_rwstat blkg_rwstat_read(struct blkg_rwstat *rwstat) struct blkg_rwstat tmp; do { - start = u64_stats_fetch_begin(&rwstat->syncp); + start = u64_stats_fetch_begin_irq(&rwstat->syncp); tmp = *rwstat; - } while (u64_stats_fetch_retry(&rwstat->syncp, start)); + } while (u64_stats_fetch_retry_irq(&rwstat->syncp, start)); return tmp; } diff --git a/block/blk-core.c b/block/blk-core.c index c0450535834..6f8dba161bf 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -16,6 +16,7 @@ #include <linux/backing-dev.h> #include <linux/bio.h> #include <linux/blkdev.h> +#include <linux/blk-mq.h> #include <linux/highmem.h> #include <linux/mm.h> #include <linux/kernel_stat.h> @@ -37,10 +38,12 @@ #include "blk.h" #include "blk-cgroup.h" +#include "blk-mq.h" EXPORT_TRACEPOINT_SYMBOL_GPL(block_bio_remap); EXPORT_TRACEPOINT_SYMBOL_GPL(block_rq_remap); EXPORT_TRACEPOINT_SYMBOL_GPL(block_bio_complete); +EXPORT_TRACEPOINT_SYMBOL_GPL(block_split); EXPORT_TRACEPOINT_SYMBOL_GPL(block_unplug); DEFINE_IDA(blk_queue_ida); @@ -48,7 +51,7 @@ DEFINE_IDA(blk_queue_ida); /* * For the allocated request tables */ -static struct kmem_cache *request_cachep; +struct kmem_cache *request_cachep = NULL; /* * For queue allocation @@ -60,42 +63,6 @@ struct kmem_cache *blk_requestq_cachep; */ static struct workqueue_struct *kblockd_workqueue; -static void drive_stat_acct(struct request *rq, int new_io) -{ - struct hd_struct *part; - int rw = rq_data_dir(rq); - int cpu; - - if (!blk_do_io_stat(rq)) - return; - - cpu = part_stat_lock(); - - if (!new_io) { - part = rq->part; - part_stat_inc(cpu, part, merges[rw]); - } else { - part = disk_map_sector_rcu(rq->rq_disk, blk_rq_pos(rq)); - if (!hd_struct_try_get(part)) { - /* - * The partition is already being removed, - * the request will be accounted on the disk only - * - * We take a reference on disk->part0 although that - * partition will never be deleted, so we can treat - * it as any other partition. - */ - part = &rq->rq_disk->part0; - hd_struct_get(part); - } - part_round_stats(cpu, part); - part_inc_in_flight(part, rw); - rq->part = part; - } - - part_stat_unlock(); -} - void blk_queue_congestion_threshold(struct request_queue *q) { int nr; @@ -145,7 +112,6 @@ void blk_rq_init(struct request_queue *q, struct request *rq) rq->cmd = rq->__cmd; rq->cmd_len = BLK_MAX_CDB; rq->tag = -1; - rq->ref_count = 1; rq->start_time = jiffies; set_start_time_ns(rq); rq->part = NULL; @@ -166,7 +132,7 @@ static void req_bio_endio(struct request *rq, struct bio *bio, bio_advance(bio, nbytes); /* don't actually finish bio if it's part of flush sequence */ - if (bio->bi_size == 0 && !(rq->cmd_flags & REQ_FLUSH_SEQ)) + if (bio->bi_iter.bi_size == 0 && !(rq->cmd_flags & REQ_FLUSH_SEQ)) bio_endio(bio, error); } @@ -174,15 +140,15 @@ void blk_dump_rq_flags(struct request *rq, char *msg) { int bit; - printk(KERN_INFO "%s: dev %s: type=%x, flags=%x\n", msg, + printk(KERN_INFO "%s: dev %s: type=%x, flags=%llx\n", msg, rq->rq_disk ? rq->rq_disk->disk_name : "?", rq->cmd_type, - rq->cmd_flags); + (unsigned long long) rq->cmd_flags); printk(KERN_INFO " sector %llu, nr/cnr %u/%u\n", (unsigned long long)blk_rq_pos(rq), blk_rq_sectors(rq), blk_rq_cur_sectors(rq)); - printk(KERN_INFO " bio %p, biotail %p, buffer %p, len %u\n", - rq->bio, rq->biotail, rq->buffer, blk_rq_bytes(rq)); + printk(KERN_INFO " bio %p, biotail %p, len %u\n", + rq->bio, rq->biotail, blk_rq_bytes(rq)); if (rq->cmd_type == REQ_TYPE_BLOCK_PC) { printk(KERN_INFO " cdb: "); @@ -281,7 +247,18 @@ EXPORT_SYMBOL(blk_stop_queue); void blk_sync_queue(struct request_queue *q) { del_timer_sync(&q->timeout); - cancel_delayed_work_sync(&q->delay_work); + + if (q->mq_ops) { + struct blk_mq_hw_ctx *hctx; + int i; + + queue_for_each_hw_ctx(q, hctx, i) { + cancel_delayed_work_sync(&hctx->run_work); + cancel_delayed_work_sync(&hctx->delay_work); + } + } else { + cancel_delayed_work_sync(&q->delay_work); + } } EXPORT_SYMBOL(blk_sync_queue); @@ -533,8 +510,13 @@ void blk_cleanup_queue(struct request_queue *q) * Drain all requests queued before DYING marking. Set DEAD flag to * prevent that q->request_fn() gets invoked after draining finished. */ - spin_lock_irq(lock); - __blk_drain_queue(q, true); + if (q->mq_ops) { + blk_mq_drain_queue(q); + spin_lock_irq(lock); + } else { + spin_lock_irq(lock); + __blk_drain_queue(q, true); + } queue_flag_set(QUEUE_FLAG_DEAD, q); spin_unlock_irq(lock); @@ -644,11 +626,15 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id) q->bypass_depth = 1; __set_bit(QUEUE_FLAG_BYPASS, &q->queue_flags); + init_waitqueue_head(&q->mq_freeze_wq); + if (blkcg_init_queue(q)) - goto fail_id; + goto fail_bdi; return q; +fail_bdi: + bdi_destroy(&q->backing_dev_info); fail_id: ida_simple_remove(&blk_queue_ida, q->id); fail_q: @@ -720,9 +706,13 @@ blk_init_allocated_queue(struct request_queue *q, request_fn_proc *rfn, if (!q) return NULL; - if (blk_init_rl(&q->root_rl, q, GFP_KERNEL)) + q->flush_rq = kzalloc(sizeof(struct request), GFP_KERNEL); + if (!q->flush_rq) return NULL; + if (blk_init_rl(&q->root_rl, q, GFP_KERNEL)) + goto fail; + q->request_fn = rfn; q->prep_rq_fn = NULL; q->unprep_rq_fn = NULL; @@ -739,10 +729,22 @@ blk_init_allocated_queue(struct request_queue *q, request_fn_proc *rfn, q->sg_reserved_size = INT_MAX; + /* Protect q->elevator from elevator_change */ + mutex_lock(&q->sysfs_lock); + /* init elevator */ - if (elevator_init(q, NULL)) - return NULL; + if (elevator_init(q, NULL)) { + mutex_unlock(&q->sysfs_lock); + goto fail; + } + + mutex_unlock(&q->sysfs_lock); + return q; + +fail: + kfree(q->flush_rq); + return NULL; } EXPORT_SYMBOL(blk_init_allocated_queue); @@ -842,6 +844,47 @@ static void freed_request(struct request_list *rl, unsigned int flags) __freed_request(rl, sync ^ 1); } +int blk_update_nr_requests(struct request_queue *q, unsigned int nr) +{ + struct request_list *rl; + + spin_lock_irq(q->queue_lock); + q->nr_requests = nr; + blk_queue_congestion_threshold(q); + + /* congestion isn't cgroup aware and follows root blkcg for now */ + rl = &q->root_rl; + + if (rl->count[BLK_RW_SYNC] >= queue_congestion_on_threshold(q)) + blk_set_queue_congested(q, BLK_RW_SYNC); + else if (rl->count[BLK_RW_SYNC] < queue_congestion_off_threshold(q)) + blk_clear_queue_congested(q, BLK_RW_SYNC); + + if (rl->count[BLK_RW_ASYNC] >= queue_congestion_on_threshold(q)) + blk_set_queue_congested(q, BLK_RW_ASYNC); + else if (rl->count[BLK_RW_ASYNC] < queue_congestion_off_threshold(q)) + blk_clear_queue_congested(q, BLK_RW_ASYNC); + + blk_queue_for_each_rl(rl, q) { + if (rl->count[BLK_RW_SYNC] >= q->nr_requests) { + blk_set_rl_full(rl, BLK_RW_SYNC); + } else { + blk_clear_rl_full(rl, BLK_RW_SYNC); + wake_up(&rl->wait[BLK_RW_SYNC]); + } + + if (rl->count[BLK_RW_ASYNC] >= q->nr_requests) { + blk_set_rl_full(rl, BLK_RW_ASYNC); + } else { + blk_clear_rl_full(rl, BLK_RW_ASYNC); + wake_up(&rl->wait[BLK_RW_ASYNC]); + } + } + + spin_unlock_irq(q->queue_lock); + return 0; +} + /* * Determine if elevator data should be initialized when allocating the * request associated with @bio. @@ -1109,7 +1152,8 @@ retry: goto retry; } -struct request *blk_get_request(struct request_queue *q, int rw, gfp_t gfp_mask) +static struct request *blk_old_get_request(struct request_queue *q, int rw, + gfp_t gfp_mask) { struct request *rq; @@ -1126,6 +1170,14 @@ struct request *blk_get_request(struct request_queue *q, int rw, gfp_t gfp_mask) return rq; } + +struct request *blk_get_request(struct request_queue *q, int rw, gfp_t gfp_mask) +{ + if (q->mq_ops) + return blk_mq_alloc_request(q, rw, gfp_mask, false); + else + return blk_old_get_request(q, rw, gfp_mask); +} EXPORT_SYMBOL(blk_get_request); /** @@ -1167,6 +1219,8 @@ struct request *blk_make_request(struct request_queue *q, struct bio *bio, if (unlikely(!rq)) return ERR_PTR(-ENOMEM); + blk_rq_set_block_pc(rq); + for_each_bio(bio) { struct bio *bounce_bio = bio; int ret; @@ -1184,6 +1238,22 @@ struct request *blk_make_request(struct request_queue *q, struct bio *bio, EXPORT_SYMBOL(blk_make_request); /** + * blk_rq_set_block_pc - initialize a requeest to type BLOCK_PC + * @rq: request to be initialized + * + */ +void blk_rq_set_block_pc(struct request *rq) +{ + rq->cmd_type = REQ_TYPE_BLOCK_PC; + rq->__data_len = 0; + rq->__sector = (sector_t) -1; + rq->bio = rq->biotail = NULL; + memset(rq->__cmd, 0, sizeof(rq->__cmd)); + rq->cmd = rq->__cmd; +} +EXPORT_SYMBOL(blk_rq_set_block_pc); + +/** * blk_requeue_request - put a request back on queue * @q: request queue where request should be inserted * @rq: request to be inserted @@ -1211,19 +1281,22 @@ EXPORT_SYMBOL(blk_requeue_request); static void add_acct_request(struct request_queue *q, struct request *rq, int where) { - drive_stat_acct(rq, 1); + blk_account_io_start(rq, true); __elv_add_request(q, rq, where); } static void part_round_stats_single(int cpu, struct hd_struct *part, unsigned long now) { + int inflight; + if (now == part->stamp) return; - if (part_in_flight(part)) { + inflight = part_in_flight(part); + if (inflight) { __part_stat_add(cpu, part, time_in_queue, - part_in_flight(part) * (now - part->stamp)); + inflight * (now - part->stamp)); __part_stat_add(cpu, part, io_ticks, (now - part->stamp)); } part->stamp = now; @@ -1272,8 +1345,11 @@ void __blk_put_request(struct request_queue *q, struct request *req) { if (unlikely(!q)) return; - if (unlikely(--req->ref_count)) + + if (q->mq_ops) { + blk_mq_free_request(req); return; + } blk_pm_put_request(req); @@ -1291,7 +1367,7 @@ void __blk_put_request(struct request_queue *q, struct request *req) struct request_list *rl = blk_rq_rl(req); BUG_ON(!list_empty(&req->queuelist)); - BUG_ON(!hlist_unhashed(&req->hash)); + BUG_ON(ELV_ON_HASH(req)); blk_free_request(rl, req); freed_request(rl, flags); @@ -1302,12 +1378,17 @@ EXPORT_SYMBOL_GPL(__blk_put_request); void blk_put_request(struct request *req) { - unsigned long flags; struct request_queue *q = req->q; - spin_lock_irqsave(q->queue_lock, flags); - __blk_put_request(q, req); - spin_unlock_irqrestore(q->queue_lock, flags); + if (q->mq_ops) + blk_mq_free_request(req); + else { + unsigned long flags; + + spin_lock_irqsave(q->queue_lock, flags); + __blk_put_request(q, req); + spin_unlock_irqrestore(q->queue_lock, flags); + } } EXPORT_SYMBOL(blk_put_request); @@ -1333,18 +1414,17 @@ void blk_add_request_payload(struct request *rq, struct page *page, bio->bi_io_vec->bv_offset = 0; bio->bi_io_vec->bv_len = len; - bio->bi_size = len; + bio->bi_iter.bi_size = len; bio->bi_vcnt = 1; bio->bi_phys_segments = 1; rq->__data_len = rq->resid_len = len; rq->nr_phys_segments = 1; - rq->buffer = bio_data(bio); } EXPORT_SYMBOL_GPL(blk_add_request_payload); -static bool bio_attempt_back_merge(struct request_queue *q, struct request *req, - struct bio *bio) +bool bio_attempt_back_merge(struct request_queue *q, struct request *req, + struct bio *bio) { const int ff = bio->bi_rw & REQ_FAILFAST_MASK; @@ -1358,15 +1438,15 @@ static bool bio_attempt_back_merge(struct request_queue *q, struct request *req, req->biotail->bi_next = bio; req->biotail = bio; - req->__data_len += bio->bi_size; + req->__data_len += bio->bi_iter.bi_size; req->ioprio = ioprio_best(req->ioprio, bio_prio(bio)); - drive_stat_acct(req, 0); + blk_account_io_start(req, false); return true; } -static bool bio_attempt_front_merge(struct request_queue *q, - struct request *req, struct bio *bio) +bool bio_attempt_front_merge(struct request_queue *q, struct request *req, + struct bio *bio) { const int ff = bio->bi_rw & REQ_FAILFAST_MASK; @@ -1381,22 +1461,16 @@ static bool bio_attempt_front_merge(struct request_queue *q, bio->bi_next = req->bio; req->bio = bio; - /* - * may not be valid. if the low level driver said - * it didn't need a bounce buffer then it better - * not touch req->buffer either... - */ - req->buffer = bio_data(bio); - req->__sector = bio->bi_sector; - req->__data_len += bio->bi_size; + req->__sector = bio->bi_iter.bi_sector; + req->__data_len += bio->bi_iter.bi_size; req->ioprio = ioprio_best(req->ioprio, bio_prio(bio)); - drive_stat_acct(req, 0); + blk_account_io_start(req, false); return true; } /** - * attempt_plug_merge - try to merge with %current's plugged list + * blk_attempt_plug_merge - try to merge with %current's plugged list * @q: request_queue new bio is being queued at * @bio: new bio being queued * @request_count: out parameter for number of traversed plugged requests @@ -1411,20 +1485,28 @@ static bool bio_attempt_front_merge(struct request_queue *q, * added on the elevator at this point. In addition, we don't have * reliable access to the elevator outside queue lock. Only check basic * merging parameters without querying the elevator. + * + * Caller must ensure !blk_queue_nomerges(q) beforehand. */ -static bool attempt_plug_merge(struct request_queue *q, struct bio *bio, - unsigned int *request_count) +bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio, + unsigned int *request_count) { struct blk_plug *plug; struct request *rq; bool ret = false; + struct list_head *plug_list; plug = current->plug; if (!plug) goto out; *request_count = 0; - list_for_each_entry_reverse(rq, &plug->list, queuelist) { + if (q->mq_ops) + plug_list = &plug->mq_list; + else + plug_list = &plug->list; + + list_for_each_entry_reverse(rq, plug_list, queuelist) { int el_ret; if (rq->q == q) @@ -1457,7 +1539,7 @@ void init_request_from_bio(struct request *req, struct bio *bio) req->cmd_flags |= REQ_FAILFAST_MASK; req->errors = 0; - req->__sector = bio->bi_sector; + req->__sector = bio->bi_iter.bi_sector; req->ioprio = bio_prio(bio); blk_rq_bio_prep(req->q, req, bio); } @@ -1492,7 +1574,8 @@ void blk_queue_bio(struct request_queue *q, struct bio *bio) * Check if we can merge with the plugged list before grabbing * any locks. */ - if (attempt_plug_merge(q, bio, &request_count)) + if (!blk_queue_nomerges(q) && + blk_attempt_plug_merge(q, bio, &request_count)) return; spin_lock_irq(q->queue_lock); @@ -1549,11 +1632,9 @@ get_rq: if (plug) { /* * If this is the first request added after a plug, fire - * of a plug trace. If others have been added before, check - * if we have multiple devices in this plug. If so, make a - * note to sort the list before dispatch. + * of a plug trace. */ - if (list_empty(&plug->list)) + if (!request_count) trace_block_plug(q); else { if (request_count >= BLK_MAX_REQUEST_COUNT) { @@ -1562,7 +1643,7 @@ get_rq: } } list_add_tail(&req->queuelist, &plug->list); - drive_stat_acct(req, 1); + blk_account_io_start(req, true); } else { spin_lock_irq(q->queue_lock); add_acct_request(q, req, where); @@ -1583,12 +1664,12 @@ static inline void blk_partition_remap(struct bio *bio) if (bio_sectors(bio) && bdev != bdev->bd_contains) { struct hd_struct *p = bdev->bd_part; - bio->bi_sector += p->start_sect; + bio->bi_iter.bi_sector += p->start_sect; bio->bi_bdev = bdev->bd_contains; trace_block_bio_remap(bdev_get_queue(bio->bi_bdev), bio, bdev->bd_dev, - bio->bi_sector - p->start_sect); + bio->bi_iter.bi_sector - p->start_sect); } } @@ -1626,7 +1707,7 @@ static int __init fail_make_request_debugfs(void) struct dentry *dir = fault_create_debugfs_attr("fail_make_request", NULL, &fail_make_request); - return IS_ERR(dir) ? PTR_ERR(dir) : 0; + return PTR_ERR_OR_ZERO(dir); } late_initcall(fail_make_request_debugfs); @@ -1654,7 +1735,7 @@ static inline int bio_check_eod(struct bio *bio, unsigned int nr_sectors) /* Test device or partition size, when known. */ maxsector = i_size_read(bio->bi_bdev->bd_inode) >> 9; if (maxsector) { - sector_t sector = bio->bi_sector; + sector_t sector = bio->bi_iter.bi_sector; if (maxsector < nr_sectors || maxsector - nr_sectors < sector) { /* @@ -1690,7 +1771,7 @@ generic_make_request_checks(struct bio *bio) "generic_make_request: Trying to access " "nonexistent block-device %s (%Lu)\n", bdevname(bio->bi_bdev, b), - (long long) bio->bi_sector); + (long long) bio->bi_iter.bi_sector); goto end_io; } @@ -1704,9 +1785,9 @@ generic_make_request_checks(struct bio *bio) } part = bio->bi_bdev->bd_part; - if (should_fail_request(part, bio->bi_size) || + if (should_fail_request(part, bio->bi_iter.bi_size) || should_fail_request(&part_to_disk(part)->part0, - bio->bi_size)) + bio->bi_iter.bi_size)) goto end_io; /* @@ -1865,7 +1946,7 @@ void submit_bio(int rw, struct bio *bio) if (rw & WRITE) { count_vm_events(PGPGOUT, count); } else { - task_io_account_read(bio->bi_size); + task_io_account_read(bio->bi_iter.bi_size); count_vm_events(PGPGIN, count); } @@ -1874,7 +1955,7 @@ void submit_bio(int rw, struct bio *bio) printk(KERN_DEBUG "%s(%d): %s block %Lu on %s (%u sectors)\n", current->comm, task_pid_nr(current), (rw & WRITE) ? "WRITE" : "READ", - (unsigned long long)bio->bi_sector, + (unsigned long long)bio->bi_iter.bi_sector, bdevname(bio->bi_bdev, b), count); } @@ -1900,7 +1981,7 @@ EXPORT_SYMBOL(submit_bio); * in some cases below, so export this function. * Request stacking drivers like request-based dm may change the queue * limits while requests are in the queue (e.g. dm's table swapping). - * Such request stacking drivers should check those requests agaist + * Such request stacking drivers should check those requests against * the new queue limits again when they dispatch those requests, * although such checkings are also done against the old queue limits * when submitting requests. @@ -2007,7 +2088,7 @@ unsigned int blk_rq_err_bytes(const struct request *rq) for (bio = rq->bio; bio; bio = bio->bi_next) { if ((bio->bi_rw & ff) != ff) break; - bytes += bio->bi_size; + bytes += bio->bi_iter.bi_size; } /* this could lead to infinite loop */ @@ -2016,7 +2097,7 @@ unsigned int blk_rq_err_bytes(const struct request *rq) } EXPORT_SYMBOL_GPL(blk_rq_err_bytes); -static void blk_account_io_completion(struct request *req, unsigned int bytes) +void blk_account_io_completion(struct request *req, unsigned int bytes) { if (blk_do_io_stat(req)) { const int rw = rq_data_dir(req); @@ -2030,7 +2111,7 @@ static void blk_account_io_completion(struct request *req, unsigned int bytes) } } -static void blk_account_io_done(struct request *req) +void blk_account_io_done(struct request *req) { /* * Account IO completion. flush_rq isn't accounted as a @@ -2078,6 +2159,42 @@ static inline struct request *blk_pm_peek_request(struct request_queue *q, } #endif +void blk_account_io_start(struct request *rq, bool new_io) +{ + struct hd_struct *part; + int rw = rq_data_dir(rq); + int cpu; + + if (!blk_do_io_stat(rq)) + return; + + cpu = part_stat_lock(); + + if (!new_io) { + part = rq->part; + part_stat_inc(cpu, part, merges[rw]); + } else { + part = disk_map_sector_rcu(rq->rq_disk, blk_rq_pos(rq)); + if (!hd_struct_try_get(part)) { + /* + * The partition is already being removed, + * the request will be accounted on the disk only + * + * We take a reference on disk->part0 although that + * partition will never be deleted, so we can treat + * it as any other partition. + */ + part = &rq->rq_disk->part0; + hd_struct_get(part); + } + part_round_stats(cpu, part); + part_inc_in_flight(part, rw); + rq->part = part; + } + + part_stat_unlock(); +} + /** * blk_peek_request - peek at the top of a request queue * @q: request queue to peek at @@ -2229,6 +2346,7 @@ void blk_start_request(struct request *req) if (unlikely(blk_bidi_rq(req))) req->next_rq->resid_len = blk_rq_bytes(req->next_rq); + BUG_ON(test_bit(REQ_ATOM_COMPLETE, &req->atomic_flags)); blk_add_timer(req); } EXPORT_SYMBOL(blk_start_request); @@ -2288,7 +2406,7 @@ bool blk_update_request(struct request *req, int error, unsigned int nr_bytes) if (!req->bio) return false; - trace_block_rq_complete(req->q, req); + trace_block_rq_complete(req->q, req, nr_bytes); /* * For fs requests, rq is just carrier of independent bio's @@ -2341,9 +2459,9 @@ bool blk_update_request(struct request *req, int error, unsigned int nr_bytes) total_bytes = 0; while (req->bio) { struct bio *bio = req->bio; - unsigned bio_bytes = min(bio->bi_size, nr_bytes); + unsigned bio_bytes = min(bio->bi_iter.bi_size, nr_bytes); - if (bio_bytes == bio->bi_size) + if (bio_bytes == bio->bi_iter.bi_size) req->bio = bio->bi_next; req_bio_endio(req, bio, bio_bytes, error); @@ -2369,7 +2487,6 @@ bool blk_update_request(struct request *req, int error, unsigned int nr_bytes) } req->__data_len -= total_bytes; - req->buffer = bio_data(req->bio); /* update sector only for requests with clear definition of sector */ if (req->cmd_type == REQ_TYPE_FS) @@ -2438,7 +2555,7 @@ EXPORT_SYMBOL_GPL(blk_unprep_request); /* * queue lock must be held */ -static void blk_finish_request(struct request *req, int error) +void blk_finish_request(struct request *req, int error) { if (blk_rq_tagged(req)) blk_queue_end_tag(req->q, req); @@ -2453,7 +2570,6 @@ static void blk_finish_request(struct request *req, int error) if (req->cmd_flags & REQ_DONTPREP) blk_unprep_request(req); - blk_account_io_done(req); if (req->end_io) @@ -2465,6 +2581,7 @@ static void blk_finish_request(struct request *req, int error) __blk_put_request(req->q, req); } } +EXPORT_SYMBOL(blk_finish_request); /** * blk_end_bidi_request - Complete a bidi request @@ -2688,11 +2805,10 @@ void blk_rq_bio_prep(struct request_queue *q, struct request *rq, /* Bit 0 (R/W) is identical in rq->cmd_flags and bio->bi_rw */ rq->cmd_flags |= bio->bi_rw & REQ_WRITE; - if (bio_has_data(bio)) { + if (bio_has_data(bio)) rq->nr_phys_segments = bio_phys_segments(q, bio); - rq->buffer = bio_data(bio); - } - rq->__data_len = bio->bi_size; + + rq->__data_len = bio->bi_iter.bi_size; rq->bio = rq->biotail = bio; if (bio->bi_bdev) @@ -2710,10 +2826,10 @@ void blk_rq_bio_prep(struct request_queue *q, struct request *rq, void rq_flush_dcache_pages(struct request *rq) { struct req_iterator iter; - struct bio_vec *bvec; + struct bio_vec bvec; rq_for_each_segment(bvec, rq, iter) - flush_dcache_page(bvec->bv_page); + flush_dcache_page(bvec.bv_page); } EXPORT_SYMBOL_GPL(rq_flush_dcache_pages); #endif @@ -2767,7 +2883,7 @@ EXPORT_SYMBOL_GPL(blk_rq_unprep_clone); /* * Copy attributes of the original request to the clone request. - * The actual data parts (e.g. ->cmd, ->buffer, ->sense) are not copied. + * The actual data parts (e.g. ->cmd, ->sense) are not copied. */ static void __blk_rq_prep_clone(struct request *dst, struct request *src) { @@ -2793,7 +2909,7 @@ static void __blk_rq_prep_clone(struct request *dst, struct request *src) * * Description: * Clones bios in @rq_src to @rq, and copies attributes of @rq_src to @rq. - * The actual data parts of @rq_src (e.g. ->cmd, ->buffer, ->sense) + * The actual data parts of @rq_src (e.g. ->cmd, ->sense) * are not copied, and copying such parts is the caller's responsibility. * Also, pages which the original bios are pointing to are not copied * and the cloned bios just point same pages. @@ -2840,20 +2956,25 @@ free_and_out: } EXPORT_SYMBOL_GPL(blk_rq_prep_clone); -int kblockd_schedule_work(struct request_queue *q, struct work_struct *work) +int kblockd_schedule_work(struct work_struct *work) { return queue_work(kblockd_workqueue, work); } EXPORT_SYMBOL(kblockd_schedule_work); -int kblockd_schedule_delayed_work(struct request_queue *q, - struct delayed_work *dwork, unsigned long delay) +int kblockd_schedule_delayed_work(struct delayed_work *dwork, + unsigned long delay) { return queue_delayed_work(kblockd_workqueue, dwork, delay); } EXPORT_SYMBOL(kblockd_schedule_delayed_work); -#define PLUG_MAGIC 0x91827364 +int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, + unsigned long delay) +{ + return queue_delayed_work_on(cpu, kblockd_workqueue, dwork, delay); +} +EXPORT_SYMBOL(kblockd_schedule_delayed_work_on); /** * blk_start_plug - initialize blk_plug and track it inside the task_struct @@ -2873,8 +2994,8 @@ void blk_start_plug(struct blk_plug *plug) { struct task_struct *tsk = current; - plug->magic = PLUG_MAGIC; INIT_LIST_HEAD(&plug->list); + INIT_LIST_HEAD(&plug->mq_list); INIT_LIST_HEAD(&plug->cb_list); /* @@ -2969,9 +3090,11 @@ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule) LIST_HEAD(list); unsigned int depth; - BUG_ON(plug->magic != PLUG_MAGIC); - flush_plug_callbacks(plug, from_schedule); + + if (!list_empty(&plug->mq_list)) + blk_mq_flush_plug_list(plug, from_schedule); + if (list_empty(&plug->list)) return; @@ -3189,8 +3312,7 @@ int __init blk_dev_init(void) /* used for unplugging and affects IO latency/throughput - HIGHPRI */ kblockd_workqueue = alloc_workqueue("kblockd", - WQ_MEM_RECLAIM | WQ_HIGHPRI | - WQ_POWER_EFFICIENT, 0); + WQ_MEM_RECLAIM | WQ_HIGHPRI, 0); if (!kblockd_workqueue) panic("Failed to create kblockd\n"); diff --git a/block/blk-exec.c b/block/blk-exec.c index e7062139612..f4d27b12c90 100644 --- a/block/blk-exec.c +++ b/block/blk-exec.c @@ -5,6 +5,7 @@ #include <linux/module.h> #include <linux/bio.h> #include <linux/blkdev.h> +#include <linux/blk-mq.h> #include <linux/sched/sysctl.h> #include "blk.h" @@ -24,7 +25,6 @@ static void blk_end_sync_rq(struct request *rq, int error) struct completion *waiting = rq->end_io_data; rq->end_io_data = NULL; - __blk_put_request(rq->q, rq); /* * complete last, if this is a stack request the process (and thus @@ -59,6 +59,16 @@ void blk_execute_rq_nowait(struct request_queue *q, struct gendisk *bd_disk, rq->rq_disk = bd_disk; rq->end_io = done; + + /* + * don't check dying flag for MQ because the request won't + * be resued after dying flag is set + */ + if (q->mq_ops) { + blk_mq_insert_request(rq, at_head, true, false); + return; + } + /* * need to check this before __blk_run_queue(), because rq can * be freed before that returns. @@ -68,9 +78,9 @@ void blk_execute_rq_nowait(struct request_queue *q, struct gendisk *bd_disk, spin_lock_irq(q->queue_lock); if (unlikely(blk_queue_dying(q))) { + rq->cmd_flags |= REQ_QUIET; rq->errors = -ENXIO; - if (rq->end_io) - rq->end_io(rq, rq->errors); + __blk_end_request_all(rq, rq->errors); spin_unlock_irq(q->queue_lock); return; } @@ -103,12 +113,6 @@ int blk_execute_rq(struct request_queue *q, struct gendisk *bd_disk, int err = 0; unsigned long hang_check; - /* - * we need an extra reference to the request, so we can look at - * it after io completion - */ - rq->ref_count++; - if (!rq->sense) { memset(sense, 0, sizeof(sense)); rq->sense = sense; @@ -128,6 +132,11 @@ int blk_execute_rq(struct request_queue *q, struct gendisk *bd_disk, if (rq->errors) err = -EIO; + if (rq->sense == sense) { + rq->sense = NULL; + rq->sense_len = 0; + } + return err; } EXPORT_SYMBOL(blk_execute_rq); diff --git a/block/blk-flush.c b/block/blk-flush.c index cc2b827a853..3cb5e9e7108 100644 --- a/block/blk-flush.c +++ b/block/blk-flush.c @@ -69,8 +69,10 @@ #include <linux/bio.h> #include <linux/blkdev.h> #include <linux/gfp.h> +#include <linux/blk-mq.h> #include "blk.h" +#include "blk-mq.h" /* FLUSH/FUA sequences */ enum { @@ -124,6 +126,25 @@ static void blk_flush_restore_request(struct request *rq) /* make @rq a normal request */ rq->cmd_flags &= ~REQ_FLUSH_SEQ; rq->end_io = rq->flush.saved_end_io; + + blk_clear_rq_complete(rq); +} + +static bool blk_flush_queue_rq(struct request *rq, bool add_front) +{ + if (rq->q->mq_ops) { + struct request_queue *q = rq->q; + + blk_mq_add_to_requeue_list(rq, add_front); + blk_mq_kick_requeue_list(q); + return false; + } else { + if (add_front) + list_add(&rq->queuelist, &rq->q->queue_head); + else + list_add_tail(&rq->queuelist, &rq->q->queue_head); + return true; + } } /** @@ -136,7 +157,7 @@ static void blk_flush_restore_request(struct request *rq) * completion and trigger the next step. * * CONTEXT: - * spin_lock_irq(q->queue_lock) + * spin_lock_irq(q->queue_lock or q->mq_flush_lock) * * RETURNS: * %true if requests were added to the dispatch queue, %false otherwise. @@ -146,7 +167,7 @@ static bool blk_flush_complete_seq(struct request *rq, unsigned int seq, { struct request_queue *q = rq->q; struct list_head *pending = &q->flush_queue[q->flush_pending_idx]; - bool queued = false; + bool queued = false, kicked; BUG_ON(rq->flush.seq & seq); rq->flush.seq |= seq; @@ -167,8 +188,7 @@ static bool blk_flush_complete_seq(struct request *rq, unsigned int seq, case REQ_FSEQ_DATA: list_move_tail(&rq->flush.list, &q->flush_data_in_flight); - list_add(&rq->queuelist, &q->queue_head); - queued = true; + queued = blk_flush_queue_rq(rq, true); break; case REQ_FSEQ_DONE: @@ -181,28 +201,41 @@ static bool blk_flush_complete_seq(struct request *rq, unsigned int seq, BUG_ON(!list_empty(&rq->queuelist)); list_del_init(&rq->flush.list); blk_flush_restore_request(rq); - __blk_end_request_all(rq, error); + if (q->mq_ops) + blk_mq_end_io(rq, error); + else + __blk_end_request_all(rq, error); break; default: BUG(); } - return blk_kick_flush(q) | queued; + kicked = blk_kick_flush(q); + return kicked | queued; } static void flush_end_io(struct request *flush_rq, int error) { struct request_queue *q = flush_rq->q; - struct list_head *running = &q->flush_queue[q->flush_running_idx]; + struct list_head *running; bool queued = false; struct request *rq, *n; + unsigned long flags = 0; + if (q->mq_ops) { + spin_lock_irqsave(&q->mq_flush_lock, flags); + q->flush_rq->tag = -1; + } + + running = &q->flush_queue[q->flush_running_idx]; BUG_ON(q->flush_pending_idx == q->flush_running_idx); /* account completion of the flush request */ q->flush_running_idx ^= 1; - elv_completed_request(q, flush_rq); + + if (!q->mq_ops) + elv_completed_request(q, flush_rq); /* and push the waiting requests to the next stage */ list_for_each_entry_safe(rq, n, running, flush.list) { @@ -223,9 +256,13 @@ static void flush_end_io(struct request *flush_rq, int error) * directly into request_fn may confuse the driver. Always use * kblockd. */ - if (queued || q->flush_queue_delayed) + if (queued || q->flush_queue_delayed) { + WARN_ON(q->mq_ops); blk_run_queue_async(q); + } q->flush_queue_delayed = 0; + if (q->mq_ops) + spin_unlock_irqrestore(&q->mq_flush_lock, flags); } /** @@ -236,7 +273,7 @@ static void flush_end_io(struct request *flush_rq, int error) * Please read the comment at the top of this file for more info. * * CONTEXT: - * spin_lock_irq(q->queue_lock) + * spin_lock_irq(q->queue_lock or q->mq_flush_lock) * * RETURNS: * %true if flush was issued, %false otherwise. @@ -261,15 +298,18 @@ static bool blk_kick_flush(struct request_queue *q) * Issue flush and toggle pending_idx. This makes pending_idx * different from running_idx, which means flush is in flight. */ - blk_rq_init(q, &q->flush_rq); - q->flush_rq.cmd_type = REQ_TYPE_FS; - q->flush_rq.cmd_flags = WRITE_FLUSH | REQ_FLUSH_SEQ; - q->flush_rq.rq_disk = first_rq->rq_disk; - q->flush_rq.end_io = flush_end_io; - q->flush_pending_idx ^= 1; - list_add_tail(&q->flush_rq.queuelist, &q->queue_head); - return true; + + blk_rq_init(q, q->flush_rq); + if (q->mq_ops) + blk_mq_clone_flush_request(q->flush_rq, first_rq); + + q->flush_rq->cmd_type = REQ_TYPE_FS; + q->flush_rq->cmd_flags = WRITE_FLUSH | REQ_FLUSH_SEQ; + q->flush_rq->rq_disk = first_rq->rq_disk; + q->flush_rq->end_io = flush_end_io; + + return blk_flush_queue_rq(q->flush_rq, false); } static void flush_data_end_io(struct request *rq, int error) @@ -284,16 +324,37 @@ static void flush_data_end_io(struct request *rq, int error) blk_run_queue_async(q); } +static void mq_flush_data_end_io(struct request *rq, int error) +{ + struct request_queue *q = rq->q; + struct blk_mq_hw_ctx *hctx; + struct blk_mq_ctx *ctx; + unsigned long flags; + + ctx = rq->mq_ctx; + hctx = q->mq_ops->map_queue(q, ctx->cpu); + + /* + * After populating an empty queue, kick it to avoid stall. Read + * the comment in flush_end_io(). + */ + spin_lock_irqsave(&q->mq_flush_lock, flags); + if (blk_flush_complete_seq(rq, REQ_FSEQ_DATA, error)) + blk_mq_run_hw_queue(hctx, true); + spin_unlock_irqrestore(&q->mq_flush_lock, flags); +} + /** * blk_insert_flush - insert a new FLUSH/FUA request * @rq: request to insert * * To be called from __elv_add_request() for %ELEVATOR_INSERT_FLUSH insertions. + * or __blk_mq_run_hw_queue() to dispatch request. * @rq is being submitted. Analyze what needs to be done and put it on the * right queue. * * CONTEXT: - * spin_lock_irq(q->queue_lock) + * spin_lock_irq(q->queue_lock) in !mq case */ void blk_insert_flush(struct request *rq) { @@ -316,7 +377,10 @@ void blk_insert_flush(struct request *rq) * complete the request. */ if (!policy) { - __blk_end_bidi_request(rq, 0, 0, 0); + if (q->mq_ops) + blk_mq_end_io(rq, 0); + else + __blk_end_bidi_request(rq, 0, 0, 0); return; } @@ -329,7 +393,10 @@ void blk_insert_flush(struct request *rq) */ if ((policy & REQ_FSEQ_DATA) && !(policy & (REQ_FSEQ_PREFLUSH | REQ_FSEQ_POSTFLUSH))) { - list_add_tail(&rq->queuelist, &q->queue_head); + if (q->mq_ops) { + blk_mq_insert_request(rq, false, false, true); + } else + list_add_tail(&rq->queuelist, &q->queue_head); return; } @@ -341,56 +408,17 @@ void blk_insert_flush(struct request *rq) INIT_LIST_HEAD(&rq->flush.list); rq->cmd_flags |= REQ_FLUSH_SEQ; rq->flush.saved_end_io = rq->end_io; /* Usually NULL */ - rq->end_io = flush_data_end_io; + if (q->mq_ops) { + rq->end_io = mq_flush_data_end_io; - blk_flush_complete_seq(rq, REQ_FSEQ_ACTIONS & ~policy, 0); -} - -/** - * blk_abort_flushes - @q is being aborted, abort flush requests - * @q: request_queue being aborted - * - * To be called from elv_abort_queue(). @q is being aborted. Prepare all - * FLUSH/FUA requests for abortion. - * - * CONTEXT: - * spin_lock_irq(q->queue_lock) - */ -void blk_abort_flushes(struct request_queue *q) -{ - struct request *rq, *n; - int i; - - /* - * Requests in flight for data are already owned by the dispatch - * queue or the device driver. Just restore for normal completion. - */ - list_for_each_entry_safe(rq, n, &q->flush_data_in_flight, flush.list) { - list_del_init(&rq->flush.list); - blk_flush_restore_request(rq); - } - - /* - * We need to give away requests on flush queues. Restore for - * normal completion and put them on the dispatch queue. - */ - for (i = 0; i < ARRAY_SIZE(q->flush_queue); i++) { - list_for_each_entry_safe(rq, n, &q->flush_queue[i], - flush.list) { - list_del_init(&rq->flush.list); - blk_flush_restore_request(rq); - list_add_tail(&rq->queuelist, &q->queue_head); - } + spin_lock_irq(&q->mq_flush_lock); + blk_flush_complete_seq(rq, REQ_FSEQ_ACTIONS & ~policy, 0); + spin_unlock_irq(&q->mq_flush_lock); + return; } -} + rq->end_io = flush_data_end_io; -static void bio_end_flush(struct bio *bio, int err) -{ - if (err) - clear_bit(BIO_UPTODATE, &bio->bi_flags); - if (bio->bi_private) - complete(bio->bi_private); - bio_put(bio); + blk_flush_complete_seq(rq, REQ_FSEQ_ACTIONS & ~policy, 0); } /** @@ -408,7 +436,6 @@ static void bio_end_flush(struct bio *bio, int err) int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask, sector_t *error_sector) { - DECLARE_COMPLETION_ONSTACK(wait); struct request_queue *q; struct bio *bio; int ret = 0; @@ -430,13 +457,9 @@ int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask, return -ENXIO; bio = bio_alloc(gfp_mask, 0); - bio->bi_end_io = bio_end_flush; bio->bi_bdev = bdev; - bio->bi_private = &wait; - bio_get(bio); - submit_bio(WRITE_FLUSH, bio); - wait_for_completion_io(&wait); + ret = submit_bio_wait(WRITE_FLUSH, bio); /* * The driver must store the error location in ->bi_sector, if @@ -444,12 +467,14 @@ int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask, * copied from blk_rq_pos(rq). */ if (error_sector) - *error_sector = bio->bi_sector; - - if (!bio_flagged(bio, BIO_UPTODATE)) - ret = -EIO; + *error_sector = bio->bi_iter.bi_sector; bio_put(bio); return ret; } EXPORT_SYMBOL(blkdev_issue_flush); + +void blk_mq_init_flush(struct request_queue *q) +{ + spin_lock_init(&q->mq_flush_lock); +} diff --git a/block/blk-integrity.c b/block/blk-integrity.c index 03cf7179e8e..7fbab84399e 100644 --- a/block/blk-integrity.c +++ b/block/blk-integrity.c @@ -43,30 +43,32 @@ static const char *bi_unsupported_name = "unsupported"; */ int blk_rq_count_integrity_sg(struct request_queue *q, struct bio *bio) { - struct bio_vec *iv, *ivprv = NULL; + struct bio_vec iv, ivprv = { NULL }; unsigned int segments = 0; unsigned int seg_size = 0; - unsigned int i = 0; + struct bvec_iter iter; + int prev = 0; - bio_for_each_integrity_vec(iv, bio, i) { + bio_for_each_integrity_vec(iv, bio, iter) { - if (ivprv) { - if (!BIOVEC_PHYS_MERGEABLE(ivprv, iv)) + if (prev) { + if (!BIOVEC_PHYS_MERGEABLE(&ivprv, &iv)) goto new_segment; - if (!BIOVEC_SEG_BOUNDARY(q, ivprv, iv)) + if (!BIOVEC_SEG_BOUNDARY(q, &ivprv, &iv)) goto new_segment; - if (seg_size + iv->bv_len > queue_max_segment_size(q)) + if (seg_size + iv.bv_len > queue_max_segment_size(q)) goto new_segment; - seg_size += iv->bv_len; + seg_size += iv.bv_len; } else { new_segment: segments++; - seg_size = iv->bv_len; + seg_size = iv.bv_len; } + prev = 1; ivprv = iv; } @@ -87,24 +89,25 @@ EXPORT_SYMBOL(blk_rq_count_integrity_sg); int blk_rq_map_integrity_sg(struct request_queue *q, struct bio *bio, struct scatterlist *sglist) { - struct bio_vec *iv, *ivprv = NULL; + struct bio_vec iv, ivprv = { NULL }; struct scatterlist *sg = NULL; unsigned int segments = 0; - unsigned int i = 0; + struct bvec_iter iter; + int prev = 0; - bio_for_each_integrity_vec(iv, bio, i) { + bio_for_each_integrity_vec(iv, bio, iter) { - if (ivprv) { - if (!BIOVEC_PHYS_MERGEABLE(ivprv, iv)) + if (prev) { + if (!BIOVEC_PHYS_MERGEABLE(&ivprv, &iv)) goto new_segment; - if (!BIOVEC_SEG_BOUNDARY(q, ivprv, iv)) + if (!BIOVEC_SEG_BOUNDARY(q, &ivprv, &iv)) goto new_segment; - if (sg->length + iv->bv_len > queue_max_segment_size(q)) + if (sg->length + iv.bv_len > queue_max_segment_size(q)) goto new_segment; - sg->length += iv->bv_len; + sg->length += iv.bv_len; } else { new_segment: if (!sg) @@ -114,10 +117,11 @@ new_segment: sg = sg_next(sg); } - sg_set_page(sg, iv->bv_page, iv->bv_len, iv->bv_offset); + sg_set_page(sg, iv.bv_page, iv.bv_len, iv.bv_offset); segments++; } + prev = 1; ivprv = iv; } diff --git a/block/blk-ioc.c b/block/blk-ioc.c index 46cd7bd18b3..1a27f45ec77 100644 --- a/block/blk-ioc.c +++ b/block/blk-ioc.c @@ -6,7 +6,6 @@ #include <linux/init.h> #include <linux/bio.h> #include <linux/blkdev.h> -#include <linux/bootmem.h> /* for max_pfn/max_low_pfn */ #include <linux/slab.h> #include "blk.h" @@ -69,7 +68,7 @@ static void ioc_destroy_icq(struct io_cq *icq) * under queue_lock. If it's not pointing to @icq now, it never * will. Hint assignment itself can race safely. */ - if (rcu_dereference_raw(ioc->icq_hint) == icq) + if (rcu_access_pointer(ioc->icq_hint) == icq) rcu_assign_pointer(ioc->icq_hint, NULL); ioc_exit_icq(icq); diff --git a/block/blk-iopoll.c b/block/blk-iopoll.c index 4b8d9b54111..0736729d649 100644 --- a/block/blk-iopoll.c +++ b/block/blk-iopoll.c @@ -14,9 +14,6 @@ #include "blk.h" -int blk_iopoll_enabled = 1; -EXPORT_SYMBOL(blk_iopoll_enabled); - static unsigned int blk_iopoll_budget __read_mostly = 256; static DEFINE_PER_CPU(struct list_head, blk_cpu_iopoll); @@ -35,7 +32,7 @@ void blk_iopoll_sched(struct blk_iopoll *iop) unsigned long flags; local_irq_save(flags); - list_add_tail(&iop->list, &__get_cpu_var(blk_cpu_iopoll)); + list_add_tail(&iop->list, this_cpu_ptr(&blk_cpu_iopoll)); __raise_softirq_irqoff(BLOCK_IOPOLL_SOFTIRQ); local_irq_restore(flags); } @@ -52,7 +49,7 @@ EXPORT_SYMBOL(blk_iopoll_sched); void __blk_iopoll_complete(struct blk_iopoll *iop) { list_del(&iop->list); - smp_mb__before_clear_bit(); + smp_mb__before_atomic(); clear_bit_unlock(IOPOLL_F_SCHED, &iop->state); } EXPORT_SYMBOL(__blk_iopoll_complete); @@ -67,19 +64,19 @@ EXPORT_SYMBOL(__blk_iopoll_complete); * iopoll handler will not be invoked again before blk_iopoll_sched_prep() * is called. **/ -void blk_iopoll_complete(struct blk_iopoll *iopoll) +void blk_iopoll_complete(struct blk_iopoll *iop) { unsigned long flags; local_irq_save(flags); - __blk_iopoll_complete(iopoll); + __blk_iopoll_complete(iop); local_irq_restore(flags); } EXPORT_SYMBOL(blk_iopoll_complete); static void blk_iopoll_softirq(struct softirq_action *h) { - struct list_head *list = &__get_cpu_var(blk_cpu_iopoll); + struct list_head *list = this_cpu_ptr(&blk_cpu_iopoll); int rearm = 0, budget = blk_iopoll_budget; unsigned long start_time = jiffies; @@ -164,7 +161,7 @@ EXPORT_SYMBOL(blk_iopoll_disable); void blk_iopoll_enable(struct blk_iopoll *iop) { BUG_ON(!test_bit(IOPOLL_F_SCHED, &iop->state)); - smp_mb__before_clear_bit(); + smp_mb__before_atomic(); clear_bit_unlock(IOPOLL_F_SCHED, &iop->state); } EXPORT_SYMBOL(blk_iopoll_enable); @@ -201,7 +198,7 @@ static int blk_iopoll_cpu_notify(struct notifier_block *self, local_irq_disable(); list_splice_init(&per_cpu(blk_cpu_iopoll, cpu), - &__get_cpu_var(blk_cpu_iopoll)); + this_cpu_ptr(&blk_cpu_iopoll)); __raise_softirq_irqoff(BLOCK_IOPOLL_SOFTIRQ); local_irq_enable(); } diff --git a/block/blk-lib.c b/block/blk-lib.c index d6f50d57256..8411be3c19d 100644 --- a/block/blk-lib.c +++ b/block/blk-lib.c @@ -43,8 +43,8 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector, DECLARE_COMPLETION_ONSTACK(wait); struct request_queue *q = bdev_get_queue(bdev); int type = REQ_WRITE | REQ_DISCARD; - sector_t max_discard_sectors; - sector_t granularity, alignment; + unsigned int max_discard_sectors, granularity; + int alignment; struct bio_batch bb; struct bio *bio; int ret = 0; @@ -58,16 +58,14 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector, /* Zero-sector (unknown) and one-sector granularities are the same. */ granularity = max(q->limits.discard_granularity >> 9, 1U); - alignment = bdev_discard_alignment(bdev) >> 9; - alignment = sector_div(alignment, granularity); + alignment = (bdev_discard_alignment(bdev) >> 9) % granularity; /* * Ensure that max_discard_sectors is of the proper * granularity, so that requests stay aligned after a split. */ max_discard_sectors = min(q->limits.max_discard_sectors, UINT_MAX >> 9); - sector_div(max_discard_sectors, granularity); - max_discard_sectors *= granularity; + max_discard_sectors -= max_discard_sectors % granularity; if (unlikely(!max_discard_sectors)) { /* Avoid infinite loop below. Being cautious never hurts. */ return -EOPNOTSUPP; @@ -110,17 +108,25 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector, req_sects = end_sect - sector; } - bio->bi_sector = sector; + bio->bi_iter.bi_sector = sector; bio->bi_end_io = bio_batch_end_io; bio->bi_bdev = bdev; bio->bi_private = &bb; - bio->bi_size = req_sects << 9; + bio->bi_iter.bi_size = req_sects << 9; nr_sects -= req_sects; sector = end_sect; atomic_inc(&bb.done); submit_bio(type, bio); + + /* + * We can loop for a long time in here, if someone does + * full device discards (like mkfs). Be nice and allow + * us to schedule out to avoid softlocking if preempt + * is disabled. + */ + cond_resched(); } blk_finish_plug(&plug); @@ -176,7 +182,7 @@ int blkdev_issue_write_same(struct block_device *bdev, sector_t sector, break; } - bio->bi_sector = sector; + bio->bi_iter.bi_sector = sector; bio->bi_end_io = bio_batch_end_io; bio->bi_bdev = bdev; bio->bi_private = &bb; @@ -186,11 +192,11 @@ int blkdev_issue_write_same(struct block_device *bdev, sector_t sector, bio->bi_io_vec->bv_len = bdev_logical_block_size(bdev); if (nr_sects > max_write_same_sectors) { - bio->bi_size = max_write_same_sectors << 9; + bio->bi_iter.bi_size = max_write_same_sectors << 9; nr_sects -= max_write_same_sectors; sector += max_write_same_sectors; } else { - bio->bi_size = nr_sects << 9; + bio->bi_iter.bi_size = nr_sects << 9; nr_sects = 0; } @@ -220,8 +226,8 @@ EXPORT_SYMBOL(blkdev_issue_write_same); * Generate and issue number of bios with zerofiled pages. */ -int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, - sector_t nr_sects, gfp_t gfp_mask) +static int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, + sector_t nr_sects, gfp_t gfp_mask) { int ret; struct bio *bio; @@ -242,7 +248,7 @@ int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, break; } - bio->bi_sector = sector; + bio->bi_iter.bi_sector = sector; bio->bi_bdev = bdev; bio->bi_end_io = bio_batch_end_io; bio->bi_private = &bb; diff --git a/block/blk-map.c b/block/blk-map.c index 623e1cd4cff..f890d4345b0 100644 --- a/block/blk-map.c +++ b/block/blk-map.c @@ -20,7 +20,7 @@ int blk_rq_append_bio(struct request_queue *q, struct request *rq, rq->biotail->bi_next = bio; rq->biotail = bio; - rq->__data_len += bio->bi_size; + rq->__data_len += bio->bi_iter.bi_size; } return 0; } @@ -76,7 +76,7 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq, ret = blk_rq_append_bio(q, rq, bio); if (!ret) - return bio->bi_size; + return bio->bi_iter.bi_size; /* if it was boucned we must call the end io function */ bio_endio(bio, 0); @@ -155,7 +155,6 @@ int blk_rq_map_user(struct request_queue *q, struct request *rq, if (!bio_flagged(bio, BIO_USER_MAPPED)) rq->cmd_flags |= REQ_COPY_USER; - rq->buffer = NULL; return 0; unmap_rq: blk_rq_unmap_user(bio); @@ -188,7 +187,7 @@ EXPORT_SYMBOL(blk_rq_map_user); * unmapping. */ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq, - struct rq_map_data *map_data, struct sg_iovec *iov, + struct rq_map_data *map_data, const struct sg_iovec *iov, int iov_count, unsigned int len, gfp_t gfp_mask) { struct bio *bio; @@ -220,7 +219,7 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq, if (IS_ERR(bio)) return PTR_ERR(bio); - if (bio->bi_size != len) { + if (bio->bi_iter.bi_size != len) { /* * Grab an extra reference to this bio, as bio_unmap_user() * expects to be able to drop it twice as it happens on the @@ -238,7 +237,6 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq, blk_queue_bounce(q, &bio); bio_get(bio); blk_rq_bio_prep(q, rq, bio); - rq->buffer = NULL; return 0; } EXPORT_SYMBOL(blk_rq_map_user_iov); @@ -285,7 +283,7 @@ EXPORT_SYMBOL(blk_rq_unmap_user); * * Description: * Data will be mapped directly if possible. Otherwise a bounce - * buffer is used. Can be called multple times to append multple + * buffer is used. Can be called multiple times to append multiple * buffers. */ int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf, @@ -325,7 +323,6 @@ int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf, } blk_queue_bounce(q, &rq->bio); - rq->buffer = NULL; return 0; } EXPORT_SYMBOL(blk_rq_map_kern); diff --git a/block/blk-merge.c b/block/blk-merge.c index 5f244825379..54535831f1e 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -12,38 +12,56 @@ static unsigned int __blk_recalc_rq_segments(struct request_queue *q, struct bio *bio) { - struct bio_vec *bv, *bvprv = NULL; - int cluster, i, high, highprv = 1; + struct bio_vec bv, bvprv = { NULL }; + int cluster, high, highprv = 1, no_sg_merge; unsigned int seg_size, nr_phys_segs; struct bio *fbio, *bbio; + struct bvec_iter iter; if (!bio) return 0; + /* + * This should probably be returning 0, but blk_add_request_payload() + * (Christoph!!!!) + */ + if (bio->bi_rw & REQ_DISCARD) + return 1; + + if (bio->bi_rw & REQ_WRITE_SAME) + return 1; + fbio = bio; cluster = blk_queue_cluster(q); seg_size = 0; nr_phys_segs = 0; + no_sg_merge = test_bit(QUEUE_FLAG_NO_SG_MERGE, &q->queue_flags); + high = 0; for_each_bio(bio) { - bio_for_each_segment(bv, bio, i) { + bio_for_each_segment(bv, bio, iter) { /* - * the trick here is making sure that a high page is - * never considered part of another segment, since that - * might change with the bounce page. + * If SG merging is disabled, each bio vector is + * a segment */ - high = page_to_pfn(bv->bv_page) > queue_bounce_pfn(q); - if (high || highprv) + if (no_sg_merge) goto new_segment; - if (cluster) { - if (seg_size + bv->bv_len + + /* + * the trick here is making sure that a high page is + * never considered part of another segment, since + * that might change with the bounce page. + */ + high = page_to_pfn(bv.bv_page) > queue_bounce_pfn(q); + if (!high && !highprv && cluster) { + if (seg_size + bv.bv_len > queue_max_segment_size(q)) goto new_segment; - if (!BIOVEC_PHYS_MERGEABLE(bvprv, bv)) + if (!BIOVEC_PHYS_MERGEABLE(&bvprv, &bv)) goto new_segment; - if (!BIOVEC_SEG_BOUNDARY(q, bvprv, bv)) + if (!BIOVEC_SEG_BOUNDARY(q, &bvprv, &bv)) goto new_segment; - seg_size += bv->bv_len; + seg_size += bv.bv_len; bvprv = bv; continue; } @@ -54,7 +72,7 @@ new_segment: nr_phys_segs++; bvprv = bv; - seg_size = bv->bv_len; + seg_size = bv.bv_len; highprv = high; } bbio = bio; @@ -75,11 +93,16 @@ void blk_recalc_rq_segments(struct request *rq) void blk_recount_segments(struct request_queue *q, struct bio *bio) { - struct bio *nxt = bio->bi_next; + if (test_bit(QUEUE_FLAG_NO_SG_MERGE, &q->queue_flags)) + bio->bi_phys_segments = bio->bi_vcnt; + else { + struct bio *nxt = bio->bi_next; + + bio->bi_next = NULL; + bio->bi_phys_segments = __blk_recalc_rq_segments(q, bio); + bio->bi_next = nxt; + } - bio->bi_next = NULL; - bio->bi_phys_segments = __blk_recalc_rq_segments(q, bio); - bio->bi_next = nxt; bio->bi_flags |= (1 << BIO_SEG_VALID); } EXPORT_SYMBOL(blk_recount_segments); @@ -87,6 +110,9 @@ EXPORT_SYMBOL(blk_recount_segments); static int blk_phys_contig_segment(struct request_queue *q, struct bio *bio, struct bio *nxt) { + struct bio_vec end_bv = { NULL }, nxt_bv; + struct bvec_iter iter; + if (!blk_queue_cluster(q)) return 0; @@ -97,34 +123,40 @@ static int blk_phys_contig_segment(struct request_queue *q, struct bio *bio, if (!bio_has_data(bio)) return 1; - if (!BIOVEC_PHYS_MERGEABLE(__BVEC_END(bio), __BVEC_START(nxt))) + bio_for_each_segment(end_bv, bio, iter) + if (end_bv.bv_len == iter.bi_size) + break; + + nxt_bv = bio_iovec(nxt); + + if (!BIOVEC_PHYS_MERGEABLE(&end_bv, &nxt_bv)) return 0; /* * bio and nxt are contiguous in memory; check if the queue allows * these two to be merged into one */ - if (BIO_SEG_BOUNDARY(q, bio, nxt)) + if (BIOVEC_SEG_BOUNDARY(q, &end_bv, &nxt_bv)) return 1; return 0; } -static void +static inline void __blk_segment_map_sg(struct request_queue *q, struct bio_vec *bvec, - struct scatterlist *sglist, struct bio_vec **bvprv, + struct scatterlist *sglist, struct bio_vec *bvprv, struct scatterlist **sg, int *nsegs, int *cluster) { int nbytes = bvec->bv_len; - if (*bvprv && *cluster) { + if (*sg && *cluster) { if ((*sg)->length + nbytes > queue_max_segment_size(q)) goto new_segment; - if (!BIOVEC_PHYS_MERGEABLE(*bvprv, bvec)) + if (!BIOVEC_PHYS_MERGEABLE(bvprv, bvec)) goto new_segment; - if (!BIOVEC_SEG_BOUNDARY(q, *bvprv, bvec)) + if (!BIOVEC_SEG_BOUNDARY(q, bvprv, bvec)) goto new_segment; (*sg)->length += nbytes; @@ -150,7 +182,49 @@ new_segment: sg_set_page(*sg, bvec->bv_page, nbytes, bvec->bv_offset); (*nsegs)++; } - *bvprv = bvec; + *bvprv = *bvec; +} + +static int __blk_bios_map_sg(struct request_queue *q, struct bio *bio, + struct scatterlist *sglist, + struct scatterlist **sg) +{ + struct bio_vec bvec, bvprv = { NULL }; + struct bvec_iter iter; + int nsegs, cluster; + + nsegs = 0; + cluster = blk_queue_cluster(q); + + if (bio->bi_rw & REQ_DISCARD) { + /* + * This is a hack - drivers should be neither modifying the + * biovec, nor relying on bi_vcnt - but because of + * blk_add_request_payload(), a discard bio may or may not have + * a payload we need to set up here (thank you Christoph) and + * bi_vcnt is really the only way of telling if we need to. + */ + + if (bio->bi_vcnt) + goto single_segment; + + return 0; + } + + if (bio->bi_rw & REQ_WRITE_SAME) { +single_segment: + *sg = sglist; + bvec = bio_iovec(bio); + sg_set_page(*sg, bvec.bv_page, bvec.bv_len, bvec.bv_offset); + return 1; + } + + for_each_bio(bio) + bio_for_each_segment(bvec, bio, iter) + __blk_segment_map_sg(q, &bvec, sglist, &bvprv, sg, + &nsegs, &cluster); + + return nsegs; } /* @@ -160,24 +234,11 @@ new_segment: int blk_rq_map_sg(struct request_queue *q, struct request *rq, struct scatterlist *sglist) { - struct bio_vec *bvec, *bvprv; - struct req_iterator iter; - struct scatterlist *sg; - int nsegs, cluster; - - nsegs = 0; - cluster = blk_queue_cluster(q); - - /* - * for each bio in rq - */ - bvprv = NULL; - sg = NULL; - rq_for_each_segment(bvec, rq, iter) { - __blk_segment_map_sg(q, bvec, sglist, &bvprv, &sg, - &nsegs, &cluster); - } /* segments in rq */ + struct scatterlist *sg = NULL; + int nsegs = 0; + if (rq->bio) + nsegs = __blk_bios_map_sg(q, rq->bio, sglist, &sg); if (unlikely(rq->cmd_flags & REQ_COPY_USER) && (blk_rq_bytes(rq) & q->dma_pad_mask)) { @@ -223,21 +284,13 @@ EXPORT_SYMBOL(blk_rq_map_sg); int blk_bio_map_sg(struct request_queue *q, struct bio *bio, struct scatterlist *sglist) { - struct bio_vec *bvec, *bvprv; - struct scatterlist *sg; - int nsegs, cluster; - unsigned long i; - - nsegs = 0; - cluster = blk_queue_cluster(q); - - bvprv = NULL; - sg = NULL; - bio_for_each_segment(bvec, bio, i) { - __blk_segment_map_sg(q, bvec, sglist, &bvprv, &sg, - &nsegs, &cluster); - } /* segments in bio */ + struct scatterlist *sg = NULL; + int nsegs; + struct bio *next = bio->bi_next; + bio->bi_next = NULL; + nsegs = __blk_bios_map_sg(q, bio, sglist, &sg); + bio->bi_next = next; if (sg) sg_mark_end(sg); @@ -308,6 +361,17 @@ int ll_front_merge_fn(struct request_queue *q, struct request *req, return ll_new_hw_segment(q, req, bio); } +/* + * blk-mq uses req->special to carry normal driver per-request payload, it + * does not indicate a prepared command that we cannot merge with. + */ +static bool req_no_special_merge(struct request *req) +{ + struct request_queue *q = req->q; + + return !q->mq_ops && req->special; +} + static int ll_merge_requests_fn(struct request_queue *q, struct request *req, struct request *next) { @@ -319,7 +383,7 @@ static int ll_merge_requests_fn(struct request_queue *q, struct request *req, * First check if the either of the requests are re-queued * requests. Can't merge them if they are. */ - if (req->special || next->special) + if (req_no_special_merge(req) || req_no_special_merge(next)) return 0; /* @@ -416,7 +480,7 @@ static int attempt_merge(struct request_queue *q, struct request *req, if (rq_data_dir(req) != rq_data_dir(next) || req->rq_disk != next->rq_disk - || next->special) + || req_no_special_merge(next)) return 0; if (req->cmd_flags & REQ_WRITE_SAME && @@ -504,6 +568,8 @@ int blk_attempt_req_merge(struct request_queue *q, struct request *rq, bool blk_rq_merge_ok(struct request *rq, struct bio *bio) { + struct request_queue *q = rq->q; + if (!rq_mergeable(rq) || !bio_mergeable(bio)) return false; @@ -515,7 +581,7 @@ bool blk_rq_merge_ok(struct request *rq, struct bio *bio) return false; /* must be same device and not a special request */ - if (rq->rq_disk != bio->bi_bdev->bd_disk || rq->special) + if (rq->rq_disk != bio->bi_bdev->bd_disk || req_no_special_merge(rq)) return false; /* only merge integrity protected bio into ditto rq */ @@ -527,14 +593,22 @@ bool blk_rq_merge_ok(struct request *rq, struct bio *bio) !blk_write_same_mergeable(rq->bio, bio)) return false; + if (q->queue_flags & (1 << QUEUE_FLAG_SG_GAPS)) { + struct bio_vec *bprev; + + bprev = &rq->biotail->bi_io_vec[bio->bi_vcnt - 1]; + if (bvec_gap_to_prev(bprev, bio->bi_io_vec[0].bv_offset)) + return false; + } + return true; } int blk_try_merge(struct request *rq, struct bio *bio) { - if (blk_rq_pos(rq) + blk_rq_sectors(rq) == bio->bi_sector) + if (blk_rq_pos(rq) + blk_rq_sectors(rq) == bio->bi_iter.bi_sector) return ELEVATOR_BACK_MERGE; - else if (blk_rq_pos(rq) - bio_sectors(bio) == bio->bi_sector) + else if (blk_rq_pos(rq) - bio_sectors(bio) == bio->bi_iter.bi_sector) return ELEVATOR_FRONT_MERGE; return ELEVATOR_NO_MERGE; } diff --git a/block/blk-mq-cpu.c b/block/blk-mq-cpu.c new file mode 100644 index 00000000000..bb3ed488f7b --- /dev/null +++ b/block/blk-mq-cpu.c @@ -0,0 +1,67 @@ +/* + * CPU notifier helper code for blk-mq + * + * Copyright (C) 2013-2014 Jens Axboe + */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/blkdev.h> +#include <linux/list.h> +#include <linux/llist.h> +#include <linux/smp.h> +#include <linux/cpu.h> + +#include <linux/blk-mq.h> +#include "blk-mq.h" + +static LIST_HEAD(blk_mq_cpu_notify_list); +static DEFINE_RAW_SPINLOCK(blk_mq_cpu_notify_lock); + +static int blk_mq_main_cpu_notify(struct notifier_block *self, + unsigned long action, void *hcpu) +{ + unsigned int cpu = (unsigned long) hcpu; + struct blk_mq_cpu_notifier *notify; + int ret = NOTIFY_OK; + + raw_spin_lock(&blk_mq_cpu_notify_lock); + + list_for_each_entry(notify, &blk_mq_cpu_notify_list, list) { + ret = notify->notify(notify->data, action, cpu); + if (ret != NOTIFY_OK) + break; + } + + raw_spin_unlock(&blk_mq_cpu_notify_lock); + return ret; +} + +void blk_mq_register_cpu_notifier(struct blk_mq_cpu_notifier *notifier) +{ + BUG_ON(!notifier->notify); + + raw_spin_lock(&blk_mq_cpu_notify_lock); + list_add_tail(¬ifier->list, &blk_mq_cpu_notify_list); + raw_spin_unlock(&blk_mq_cpu_notify_lock); +} + +void blk_mq_unregister_cpu_notifier(struct blk_mq_cpu_notifier *notifier) +{ + raw_spin_lock(&blk_mq_cpu_notify_lock); + list_del(¬ifier->list); + raw_spin_unlock(&blk_mq_cpu_notify_lock); +} + +void blk_mq_init_cpu_notifier(struct blk_mq_cpu_notifier *notifier, + int (*fn)(void *, unsigned long, unsigned int), + void *data) +{ + notifier->notify = fn; + notifier->data = data; +} + +void __init blk_mq_cpu_init(void) +{ + hotcpu_notifier(blk_mq_main_cpu_notify, 0); +} diff --git a/block/blk-mq-cpumap.c b/block/blk-mq-cpumap.c new file mode 100644 index 00000000000..1065d7c65fa --- /dev/null +++ b/block/blk-mq-cpumap.c @@ -0,0 +1,119 @@ +/* + * CPU <-> hardware queue mapping helpers + * + * Copyright (C) 2013-2014 Jens Axboe + */ +#include <linux/kernel.h> +#include <linux/threads.h> +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/smp.h> +#include <linux/cpu.h> + +#include <linux/blk-mq.h> +#include "blk.h" +#include "blk-mq.h" + +static int cpu_to_queue_index(unsigned int nr_cpus, unsigned int nr_queues, + const int cpu) +{ + return cpu / ((nr_cpus + nr_queues - 1) / nr_queues); +} + +static int get_first_sibling(unsigned int cpu) +{ + unsigned int ret; + + ret = cpumask_first(topology_thread_cpumask(cpu)); + if (ret < nr_cpu_ids) + return ret; + + return cpu; +} + +int blk_mq_update_queue_map(unsigned int *map, unsigned int nr_queues) +{ + unsigned int i, nr_cpus, nr_uniq_cpus, queue, first_sibling; + cpumask_var_t cpus; + + if (!alloc_cpumask_var(&cpus, GFP_ATOMIC)) + return 1; + + cpumask_clear(cpus); + nr_cpus = nr_uniq_cpus = 0; + for_each_online_cpu(i) { + nr_cpus++; + first_sibling = get_first_sibling(i); + if (!cpumask_test_cpu(first_sibling, cpus)) + nr_uniq_cpus++; + cpumask_set_cpu(i, cpus); + } + + queue = 0; + for_each_possible_cpu(i) { + if (!cpu_online(i)) { + map[i] = 0; + continue; + } + + /* + * Easy case - we have equal or more hardware queues. Or + * there are no thread siblings to take into account. Do + * 1:1 if enough, or sequential mapping if less. + */ + if (nr_queues >= nr_cpus || nr_cpus == nr_uniq_cpus) { + map[i] = cpu_to_queue_index(nr_cpus, nr_queues, queue); + queue++; + continue; + } + + /* + * Less then nr_cpus queues, and we have some number of + * threads per cores. Map sibling threads to the same + * queue. + */ + first_sibling = get_first_sibling(i); + if (first_sibling == i) { + map[i] = cpu_to_queue_index(nr_uniq_cpus, nr_queues, + queue); + queue++; + } else + map[i] = map[first_sibling]; + } + + free_cpumask_var(cpus); + return 0; +} + +unsigned int *blk_mq_make_queue_map(struct blk_mq_tag_set *set) +{ + unsigned int *map; + + /* If cpus are offline, map them to first hctx */ + map = kzalloc_node(sizeof(*map) * num_possible_cpus(), GFP_KERNEL, + set->numa_node); + if (!map) + return NULL; + + if (!blk_mq_update_queue_map(map, set->nr_hw_queues)) + return map; + + kfree(map); + return NULL; +} + +/* + * We have no quick way of doing reverse lookups. This is only used at + * queue init time, so runtime isn't important. + */ +int blk_mq_hw_queue_to_node(unsigned int *mq_map, unsigned int index) +{ + int i; + + for_each_possible_cpu(i) { + if (index == mq_map[i]) + return cpu_to_node(i); + } + + return NUMA_NO_NODE; +} diff --git a/block/blk-mq-sysfs.c b/block/blk-mq-sysfs.c new file mode 100644 index 00000000000..ed521786755 --- /dev/null +++ b/block/blk-mq-sysfs.c @@ -0,0 +1,456 @@ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/backing-dev.h> +#include <linux/bio.h> +#include <linux/blkdev.h> +#include <linux/mm.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/workqueue.h> +#include <linux/smp.h> + +#include <linux/blk-mq.h> +#include "blk-mq.h" +#include "blk-mq-tag.h" + +static void blk_mq_sysfs_release(struct kobject *kobj) +{ +} + +struct blk_mq_ctx_sysfs_entry { + struct attribute attr; + ssize_t (*show)(struct blk_mq_ctx *, char *); + ssize_t (*store)(struct blk_mq_ctx *, const char *, size_t); +}; + +struct blk_mq_hw_ctx_sysfs_entry { + struct attribute attr; + ssize_t (*show)(struct blk_mq_hw_ctx *, char *); + ssize_t (*store)(struct blk_mq_hw_ctx *, const char *, size_t); +}; + +static ssize_t blk_mq_sysfs_show(struct kobject *kobj, struct attribute *attr, + char *page) +{ + struct blk_mq_ctx_sysfs_entry *entry; + struct blk_mq_ctx *ctx; + struct request_queue *q; + ssize_t res; + + entry = container_of(attr, struct blk_mq_ctx_sysfs_entry, attr); + ctx = container_of(kobj, struct blk_mq_ctx, kobj); + q = ctx->queue; + + if (!entry->show) + return -EIO; + + res = -ENOENT; + mutex_lock(&q->sysfs_lock); + if (!blk_queue_dying(q)) + res = entry->show(ctx, page); + mutex_unlock(&q->sysfs_lock); + return res; +} + +static ssize_t blk_mq_sysfs_store(struct kobject *kobj, struct attribute *attr, + const char *page, size_t length) +{ + struct blk_mq_ctx_sysfs_entry *entry; + struct blk_mq_ctx *ctx; + struct request_queue *q; + ssize_t res; + + entry = container_of(attr, struct blk_mq_ctx_sysfs_entry, attr); + ctx = container_of(kobj, struct blk_mq_ctx, kobj); + q = ctx->queue; + + if (!entry->store) + return -EIO; + + res = -ENOENT; + mutex_lock(&q->sysfs_lock); + if (!blk_queue_dying(q)) + res = entry->store(ctx, page, length); + mutex_unlock(&q->sysfs_lock); + return res; +} + +static ssize_t blk_mq_hw_sysfs_show(struct kobject *kobj, + struct attribute *attr, char *page) +{ + struct blk_mq_hw_ctx_sysfs_entry *entry; + struct blk_mq_hw_ctx *hctx; + struct request_queue *q; + ssize_t res; + + entry = container_of(attr, struct blk_mq_hw_ctx_sysfs_entry, attr); + hctx = container_of(kobj, struct blk_mq_hw_ctx, kobj); + q = hctx->queue; + + if (!entry->show) + return -EIO; + + res = -ENOENT; + mutex_lock(&q->sysfs_lock); + if (!blk_queue_dying(q)) + res = entry->show(hctx, page); + mutex_unlock(&q->sysfs_lock); + return res; +} + +static ssize_t blk_mq_hw_sysfs_store(struct kobject *kobj, + struct attribute *attr, const char *page, + size_t length) +{ + struct blk_mq_hw_ctx_sysfs_entry *entry; + struct blk_mq_hw_ctx *hctx; + struct request_queue *q; + ssize_t res; + + entry = container_of(attr, struct blk_mq_hw_ctx_sysfs_entry, attr); + hctx = container_of(kobj, struct blk_mq_hw_ctx, kobj); + q = hctx->queue; + + if (!entry->store) + return -EIO; + + res = -ENOENT; + mutex_lock(&q->sysfs_lock); + if (!blk_queue_dying(q)) + res = entry->store(hctx, page, length); + mutex_unlock(&q->sysfs_lock); + return res; +} + +static ssize_t blk_mq_sysfs_dispatched_show(struct blk_mq_ctx *ctx, char *page) +{ + return sprintf(page, "%lu %lu\n", ctx->rq_dispatched[1], + ctx->rq_dispatched[0]); +} + +static ssize_t blk_mq_sysfs_merged_show(struct blk_mq_ctx *ctx, char *page) +{ + return sprintf(page, "%lu\n", ctx->rq_merged); +} + +static ssize_t blk_mq_sysfs_completed_show(struct blk_mq_ctx *ctx, char *page) +{ + return sprintf(page, "%lu %lu\n", ctx->rq_completed[1], + ctx->rq_completed[0]); +} + +static ssize_t sysfs_list_show(char *page, struct list_head *list, char *msg) +{ + char *start_page = page; + struct request *rq; + + page += sprintf(page, "%s:\n", msg); + + list_for_each_entry(rq, list, queuelist) + page += sprintf(page, "\t%p\n", rq); + + return page - start_page; +} + +static ssize_t blk_mq_sysfs_rq_list_show(struct blk_mq_ctx *ctx, char *page) +{ + ssize_t ret; + + spin_lock(&ctx->lock); + ret = sysfs_list_show(page, &ctx->rq_list, "CTX pending"); + spin_unlock(&ctx->lock); + + return ret; +} + +static ssize_t blk_mq_hw_sysfs_queued_show(struct blk_mq_hw_ctx *hctx, + char *page) +{ + return sprintf(page, "%lu\n", hctx->queued); +} + +static ssize_t blk_mq_hw_sysfs_run_show(struct blk_mq_hw_ctx *hctx, char *page) +{ + return sprintf(page, "%lu\n", hctx->run); +} + +static ssize_t blk_mq_hw_sysfs_dispatched_show(struct blk_mq_hw_ctx *hctx, + char *page) +{ + char *start_page = page; + int i; + + page += sprintf(page, "%8u\t%lu\n", 0U, hctx->dispatched[0]); + + for (i = 1; i < BLK_MQ_MAX_DISPATCH_ORDER; i++) { + unsigned long d = 1U << (i - 1); + + page += sprintf(page, "%8lu\t%lu\n", d, hctx->dispatched[i]); + } + + return page - start_page; +} + +static ssize_t blk_mq_hw_sysfs_rq_list_show(struct blk_mq_hw_ctx *hctx, + char *page) +{ + ssize_t ret; + + spin_lock(&hctx->lock); + ret = sysfs_list_show(page, &hctx->dispatch, "HCTX pending"); + spin_unlock(&hctx->lock); + + return ret; +} + +static ssize_t blk_mq_hw_sysfs_tags_show(struct blk_mq_hw_ctx *hctx, char *page) +{ + return blk_mq_tag_sysfs_show(hctx->tags, page); +} + +static ssize_t blk_mq_hw_sysfs_active_show(struct blk_mq_hw_ctx *hctx, char *page) +{ + return sprintf(page, "%u\n", atomic_read(&hctx->nr_active)); +} + +static ssize_t blk_mq_hw_sysfs_cpus_show(struct blk_mq_hw_ctx *hctx, char *page) +{ + unsigned int i, first = 1; + ssize_t ret = 0; + + blk_mq_disable_hotplug(); + + for_each_cpu(i, hctx->cpumask) { + if (first) + ret += sprintf(ret + page, "%u", i); + else + ret += sprintf(ret + page, ", %u", i); + + first = 0; + } + + blk_mq_enable_hotplug(); + + ret += sprintf(ret + page, "\n"); + return ret; +} + +static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_dispatched = { + .attr = {.name = "dispatched", .mode = S_IRUGO }, + .show = blk_mq_sysfs_dispatched_show, +}; +static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_merged = { + .attr = {.name = "merged", .mode = S_IRUGO }, + .show = blk_mq_sysfs_merged_show, +}; +static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_completed = { + .attr = {.name = "completed", .mode = S_IRUGO }, + .show = blk_mq_sysfs_completed_show, +}; +static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_rq_list = { + .attr = {.name = "rq_list", .mode = S_IRUGO }, + .show = blk_mq_sysfs_rq_list_show, +}; + +static struct attribute *default_ctx_attrs[] = { + &blk_mq_sysfs_dispatched.attr, + &blk_mq_sysfs_merged.attr, + &blk_mq_sysfs_completed.attr, + &blk_mq_sysfs_rq_list.attr, + NULL, +}; + +static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_queued = { + .attr = {.name = "queued", .mode = S_IRUGO }, + .show = blk_mq_hw_sysfs_queued_show, +}; +static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_run = { + .attr = {.name = "run", .mode = S_IRUGO }, + .show = blk_mq_hw_sysfs_run_show, +}; +static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_dispatched = { + .attr = {.name = "dispatched", .mode = S_IRUGO }, + .show = blk_mq_hw_sysfs_dispatched_show, +}; +static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_active = { + .attr = {.name = "active", .mode = S_IRUGO }, + .show = blk_mq_hw_sysfs_active_show, +}; +static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_pending = { + .attr = {.name = "pending", .mode = S_IRUGO }, + .show = blk_mq_hw_sysfs_rq_list_show, +}; +static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_tags = { + .attr = {.name = "tags", .mode = S_IRUGO }, + .show = blk_mq_hw_sysfs_tags_show, +}; +static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_cpus = { + .attr = {.name = "cpu_list", .mode = S_IRUGO }, + .show = blk_mq_hw_sysfs_cpus_show, +}; + +static struct attribute *default_hw_ctx_attrs[] = { + &blk_mq_hw_sysfs_queued.attr, + &blk_mq_hw_sysfs_run.attr, + &blk_mq_hw_sysfs_dispatched.attr, + &blk_mq_hw_sysfs_pending.attr, + &blk_mq_hw_sysfs_tags.attr, + &blk_mq_hw_sysfs_cpus.attr, + &blk_mq_hw_sysfs_active.attr, + NULL, +}; + +static const struct sysfs_ops blk_mq_sysfs_ops = { + .show = blk_mq_sysfs_show, + .store = blk_mq_sysfs_store, +}; + +static const struct sysfs_ops blk_mq_hw_sysfs_ops = { + .show = blk_mq_hw_sysfs_show, + .store = blk_mq_hw_sysfs_store, +}; + +static struct kobj_type blk_mq_ktype = { + .sysfs_ops = &blk_mq_sysfs_ops, + .release = blk_mq_sysfs_release, +}; + +static struct kobj_type blk_mq_ctx_ktype = { + .sysfs_ops = &blk_mq_sysfs_ops, + .default_attrs = default_ctx_attrs, + .release = blk_mq_sysfs_release, +}; + +static struct kobj_type blk_mq_hw_ktype = { + .sysfs_ops = &blk_mq_hw_sysfs_ops, + .default_attrs = default_hw_ctx_attrs, + .release = blk_mq_sysfs_release, +}; + +static void blk_mq_unregister_hctx(struct blk_mq_hw_ctx *hctx) +{ + struct blk_mq_ctx *ctx; + int i; + + if (!hctx->nr_ctx || !(hctx->flags & BLK_MQ_F_SYSFS_UP)) + return; + + hctx_for_each_ctx(hctx, ctx, i) + kobject_del(&ctx->kobj); + + kobject_del(&hctx->kobj); +} + +static int blk_mq_register_hctx(struct blk_mq_hw_ctx *hctx) +{ + struct request_queue *q = hctx->queue; + struct blk_mq_ctx *ctx; + int i, ret; + + if (!hctx->nr_ctx || !(hctx->flags & BLK_MQ_F_SYSFS_UP)) + return 0; + + ret = kobject_add(&hctx->kobj, &q->mq_kobj, "%u", hctx->queue_num); + if (ret) + return ret; + + hctx_for_each_ctx(hctx, ctx, i) { + ret = kobject_add(&ctx->kobj, &hctx->kobj, "cpu%u", ctx->cpu); + if (ret) + break; + } + + return ret; +} + +void blk_mq_unregister_disk(struct gendisk *disk) +{ + struct request_queue *q = disk->queue; + struct blk_mq_hw_ctx *hctx; + struct blk_mq_ctx *ctx; + int i, j; + + queue_for_each_hw_ctx(q, hctx, i) { + blk_mq_unregister_hctx(hctx); + + hctx_for_each_ctx(hctx, ctx, j) + kobject_put(&ctx->kobj); + + kobject_put(&hctx->kobj); + } + + kobject_uevent(&q->mq_kobj, KOBJ_REMOVE); + kobject_del(&q->mq_kobj); + kobject_put(&q->mq_kobj); + + kobject_put(&disk_to_dev(disk)->kobj); +} + +static void blk_mq_sysfs_init(struct request_queue *q) +{ + struct blk_mq_hw_ctx *hctx; + struct blk_mq_ctx *ctx; + int i, j; + + kobject_init(&q->mq_kobj, &blk_mq_ktype); + + queue_for_each_hw_ctx(q, hctx, i) { + kobject_init(&hctx->kobj, &blk_mq_hw_ktype); + + hctx_for_each_ctx(hctx, ctx, j) + kobject_init(&ctx->kobj, &blk_mq_ctx_ktype); + } +} + +int blk_mq_register_disk(struct gendisk *disk) +{ + struct device *dev = disk_to_dev(disk); + struct request_queue *q = disk->queue; + struct blk_mq_hw_ctx *hctx; + int ret, i; + + blk_mq_sysfs_init(q); + + ret = kobject_add(&q->mq_kobj, kobject_get(&dev->kobj), "%s", "mq"); + if (ret < 0) + return ret; + + kobject_uevent(&q->mq_kobj, KOBJ_ADD); + + queue_for_each_hw_ctx(q, hctx, i) { + hctx->flags |= BLK_MQ_F_SYSFS_UP; + ret = blk_mq_register_hctx(hctx); + if (ret) + break; + } + + if (ret) { + blk_mq_unregister_disk(disk); + return ret; + } + + return 0; +} + +void blk_mq_sysfs_unregister(struct request_queue *q) +{ + struct blk_mq_hw_ctx *hctx; + int i; + + queue_for_each_hw_ctx(q, hctx, i) + blk_mq_unregister_hctx(hctx); +} + +int blk_mq_sysfs_register(struct request_queue *q) +{ + struct blk_mq_hw_ctx *hctx; + int i, ret = 0; + + queue_for_each_hw_ctx(q, hctx, i) { + ret = blk_mq_register_hctx(hctx); + if (ret) + break; + } + + return ret; +} diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c new file mode 100644 index 00000000000..c1b92426c95 --- /dev/null +++ b/block/blk-mq-tag.c @@ -0,0 +1,618 @@ +/* + * Fast and scalable bitmap tagging variant. Uses sparser bitmaps spread + * over multiple cachelines to avoid ping-pong between multiple submitters + * or submitter and completer. Uses rolling wakeups to avoid falling of + * the scaling cliff when we run out of tags and have to start putting + * submitters to sleep. + * + * Uses active queue tracking to support fairer distribution of tags + * between multiple submitters when a shared tag map is used. + * + * Copyright (C) 2013-2014 Jens Axboe + */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/random.h> + +#include <linux/blk-mq.h> +#include "blk.h" +#include "blk-mq.h" +#include "blk-mq-tag.h" + +static bool bt_has_free_tags(struct blk_mq_bitmap_tags *bt) +{ + int i; + + for (i = 0; i < bt->map_nr; i++) { + struct blk_align_bitmap *bm = &bt->map[i]; + int ret; + + ret = find_first_zero_bit(&bm->word, bm->depth); + if (ret < bm->depth) + return true; + } + + return false; +} + +bool blk_mq_has_free_tags(struct blk_mq_tags *tags) +{ + if (!tags) + return true; + + return bt_has_free_tags(&tags->bitmap_tags); +} + +static inline int bt_index_inc(int index) +{ + return (index + 1) & (BT_WAIT_QUEUES - 1); +} + +static inline void bt_index_atomic_inc(atomic_t *index) +{ + int old = atomic_read(index); + int new = bt_index_inc(old); + atomic_cmpxchg(index, old, new); +} + +/* + * If a previously inactive queue goes active, bump the active user count. + */ +bool __blk_mq_tag_busy(struct blk_mq_hw_ctx *hctx) +{ + if (!test_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state) && + !test_and_set_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state)) + atomic_inc(&hctx->tags->active_queues); + + return true; +} + +/* + * Wakeup all potentially sleeping on normal (non-reserved) tags + */ +static void blk_mq_tag_wakeup_all(struct blk_mq_tags *tags) +{ + struct blk_mq_bitmap_tags *bt; + int i, wake_index; + + bt = &tags->bitmap_tags; + wake_index = atomic_read(&bt->wake_index); + for (i = 0; i < BT_WAIT_QUEUES; i++) { + struct bt_wait_state *bs = &bt->bs[wake_index]; + + if (waitqueue_active(&bs->wait)) + wake_up(&bs->wait); + + wake_index = bt_index_inc(wake_index); + } +} + +/* + * If a previously busy queue goes inactive, potential waiters could now + * be allowed to queue. Wake them up and check. + */ +void __blk_mq_tag_idle(struct blk_mq_hw_ctx *hctx) +{ + struct blk_mq_tags *tags = hctx->tags; + + if (!test_and_clear_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state)) + return; + + atomic_dec(&tags->active_queues); + + blk_mq_tag_wakeup_all(tags); +} + +/* + * For shared tag users, we track the number of currently active users + * and attempt to provide a fair share of the tag depth for each of them. + */ +static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx, + struct blk_mq_bitmap_tags *bt) +{ + unsigned int depth, users; + + if (!hctx || !(hctx->flags & BLK_MQ_F_TAG_SHARED)) + return true; + if (!test_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state)) + return true; + + /* + * Don't try dividing an ant + */ + if (bt->depth == 1) + return true; + + users = atomic_read(&hctx->tags->active_queues); + if (!users) + return true; + + /* + * Allow at least some tags + */ + depth = max((bt->depth + users - 1) / users, 4U); + return atomic_read(&hctx->nr_active) < depth; +} + +static int __bt_get_word(struct blk_align_bitmap *bm, unsigned int last_tag) +{ + int tag, org_last_tag, end; + + org_last_tag = last_tag; + end = bm->depth; + do { +restart: + tag = find_next_zero_bit(&bm->word, end, last_tag); + if (unlikely(tag >= end)) { + /* + * We started with an offset, start from 0 to + * exhaust the map. + */ + if (org_last_tag && last_tag) { + end = last_tag; + last_tag = 0; + goto restart; + } + return -1; + } + last_tag = tag + 1; + } while (test_and_set_bit_lock(tag, &bm->word)); + + return tag; +} + +/* + * Straight forward bitmap tag implementation, where each bit is a tag + * (cleared == free, and set == busy). The small twist is using per-cpu + * last_tag caches, which blk-mq stores in the blk_mq_ctx software queue + * contexts. This enables us to drastically limit the space searched, + * without dirtying an extra shared cacheline like we would if we stored + * the cache value inside the shared blk_mq_bitmap_tags structure. On top + * of that, each word of tags is in a separate cacheline. This means that + * multiple users will tend to stick to different cachelines, at least + * until the map is exhausted. + */ +static int __bt_get(struct blk_mq_hw_ctx *hctx, struct blk_mq_bitmap_tags *bt, + unsigned int *tag_cache) +{ + unsigned int last_tag, org_last_tag; + int index, i, tag; + + if (!hctx_may_queue(hctx, bt)) + return -1; + + last_tag = org_last_tag = *tag_cache; + index = TAG_TO_INDEX(bt, last_tag); + + for (i = 0; i < bt->map_nr; i++) { + tag = __bt_get_word(&bt->map[index], TAG_TO_BIT(bt, last_tag)); + if (tag != -1) { + tag += (index << bt->bits_per_word); + goto done; + } + + last_tag = 0; + if (++index >= bt->map_nr) + index = 0; + } + + *tag_cache = 0; + return -1; + + /* + * Only update the cache from the allocation path, if we ended + * up using the specific cached tag. + */ +done: + if (tag == org_last_tag) { + last_tag = tag + 1; + if (last_tag >= bt->depth - 1) + last_tag = 0; + + *tag_cache = last_tag; + } + + return tag; +} + +static struct bt_wait_state *bt_wait_ptr(struct blk_mq_bitmap_tags *bt, + struct blk_mq_hw_ctx *hctx) +{ + struct bt_wait_state *bs; + int wait_index; + + if (!hctx) + return &bt->bs[0]; + + wait_index = atomic_read(&hctx->wait_index); + bs = &bt->bs[wait_index]; + bt_index_atomic_inc(&hctx->wait_index); + return bs; +} + +static int bt_get(struct blk_mq_alloc_data *data, + struct blk_mq_bitmap_tags *bt, + struct blk_mq_hw_ctx *hctx, + unsigned int *last_tag) +{ + struct bt_wait_state *bs; + DEFINE_WAIT(wait); + int tag; + + tag = __bt_get(hctx, bt, last_tag); + if (tag != -1) + return tag; + + if (!(data->gfp & __GFP_WAIT)) + return -1; + + bs = bt_wait_ptr(bt, hctx); + do { + prepare_to_wait(&bs->wait, &wait, TASK_UNINTERRUPTIBLE); + + tag = __bt_get(hctx, bt, last_tag); + if (tag != -1) + break; + + blk_mq_put_ctx(data->ctx); + + io_schedule(); + + data->ctx = blk_mq_get_ctx(data->q); + data->hctx = data->q->mq_ops->map_queue(data->q, + data->ctx->cpu); + if (data->reserved) { + bt = &data->hctx->tags->breserved_tags; + } else { + last_tag = &data->ctx->last_tag; + hctx = data->hctx; + bt = &hctx->tags->bitmap_tags; + } + finish_wait(&bs->wait, &wait); + bs = bt_wait_ptr(bt, hctx); + } while (1); + + finish_wait(&bs->wait, &wait); + return tag; +} + +static unsigned int __blk_mq_get_tag(struct blk_mq_alloc_data *data) +{ + int tag; + + tag = bt_get(data, &data->hctx->tags->bitmap_tags, data->hctx, + &data->ctx->last_tag); + if (tag >= 0) + return tag + data->hctx->tags->nr_reserved_tags; + + return BLK_MQ_TAG_FAIL; +} + +static unsigned int __blk_mq_get_reserved_tag(struct blk_mq_alloc_data *data) +{ + int tag, zero = 0; + + if (unlikely(!data->hctx->tags->nr_reserved_tags)) { + WARN_ON_ONCE(1); + return BLK_MQ_TAG_FAIL; + } + + tag = bt_get(data, &data->hctx->tags->breserved_tags, NULL, &zero); + if (tag < 0) + return BLK_MQ_TAG_FAIL; + + return tag; +} + +unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data) +{ + if (!data->reserved) + return __blk_mq_get_tag(data); + + return __blk_mq_get_reserved_tag(data); +} + +static struct bt_wait_state *bt_wake_ptr(struct blk_mq_bitmap_tags *bt) +{ + int i, wake_index; + + wake_index = atomic_read(&bt->wake_index); + for (i = 0; i < BT_WAIT_QUEUES; i++) { + struct bt_wait_state *bs = &bt->bs[wake_index]; + + if (waitqueue_active(&bs->wait)) { + int o = atomic_read(&bt->wake_index); + if (wake_index != o) + atomic_cmpxchg(&bt->wake_index, o, wake_index); + + return bs; + } + + wake_index = bt_index_inc(wake_index); + } + + return NULL; +} + +static void bt_clear_tag(struct blk_mq_bitmap_tags *bt, unsigned int tag) +{ + const int index = TAG_TO_INDEX(bt, tag); + struct bt_wait_state *bs; + int wait_cnt; + + /* + * The unlock memory barrier need to order access to req in free + * path and clearing tag bit + */ + clear_bit_unlock(TAG_TO_BIT(bt, tag), &bt->map[index].word); + + bs = bt_wake_ptr(bt); + if (!bs) + return; + + wait_cnt = atomic_dec_return(&bs->wait_cnt); + if (wait_cnt == 0) { +wake: + atomic_add(bt->wake_cnt, &bs->wait_cnt); + bt_index_atomic_inc(&bt->wake_index); + wake_up(&bs->wait); + } else if (wait_cnt < 0) { + wait_cnt = atomic_inc_return(&bs->wait_cnt); + if (!wait_cnt) + goto wake; + } +} + +static void __blk_mq_put_tag(struct blk_mq_tags *tags, unsigned int tag) +{ + BUG_ON(tag >= tags->nr_tags); + + bt_clear_tag(&tags->bitmap_tags, tag); +} + +static void __blk_mq_put_reserved_tag(struct blk_mq_tags *tags, + unsigned int tag) +{ + BUG_ON(tag >= tags->nr_reserved_tags); + + bt_clear_tag(&tags->breserved_tags, tag); +} + +void blk_mq_put_tag(struct blk_mq_hw_ctx *hctx, unsigned int tag, + unsigned int *last_tag) +{ + struct blk_mq_tags *tags = hctx->tags; + + if (tag >= tags->nr_reserved_tags) { + const int real_tag = tag - tags->nr_reserved_tags; + + __blk_mq_put_tag(tags, real_tag); + *last_tag = real_tag; + } else + __blk_mq_put_reserved_tag(tags, tag); +} + +static void bt_for_each_free(struct blk_mq_bitmap_tags *bt, + unsigned long *free_map, unsigned int off) +{ + int i; + + for (i = 0; i < bt->map_nr; i++) { + struct blk_align_bitmap *bm = &bt->map[i]; + int bit = 0; + + do { + bit = find_next_zero_bit(&bm->word, bm->depth, bit); + if (bit >= bm->depth) + break; + + __set_bit(bit + off, free_map); + bit++; + } while (1); + + off += (1 << bt->bits_per_word); + } +} + +void blk_mq_tag_busy_iter(struct blk_mq_tags *tags, + void (*fn)(void *, unsigned long *), void *data) +{ + unsigned long *tag_map; + size_t map_size; + + map_size = ALIGN(tags->nr_tags, BITS_PER_LONG) / BITS_PER_LONG; + tag_map = kzalloc(map_size * sizeof(unsigned long), GFP_ATOMIC); + if (!tag_map) + return; + + bt_for_each_free(&tags->bitmap_tags, tag_map, tags->nr_reserved_tags); + if (tags->nr_reserved_tags) + bt_for_each_free(&tags->breserved_tags, tag_map, 0); + + fn(data, tag_map); + kfree(tag_map); +} +EXPORT_SYMBOL(blk_mq_tag_busy_iter); + +static unsigned int bt_unused_tags(struct blk_mq_bitmap_tags *bt) +{ + unsigned int i, used; + + for (i = 0, used = 0; i < bt->map_nr; i++) { + struct blk_align_bitmap *bm = &bt->map[i]; + + used += bitmap_weight(&bm->word, bm->depth); + } + + return bt->depth - used; +} + +static void bt_update_count(struct blk_mq_bitmap_tags *bt, + unsigned int depth) +{ + unsigned int tags_per_word = 1U << bt->bits_per_word; + unsigned int map_depth = depth; + + if (depth) { + int i; + + for (i = 0; i < bt->map_nr; i++) { + bt->map[i].depth = min(map_depth, tags_per_word); + map_depth -= bt->map[i].depth; + } + } + + bt->wake_cnt = BT_WAIT_BATCH; + if (bt->wake_cnt > depth / 4) + bt->wake_cnt = max(1U, depth / 4); + + bt->depth = depth; +} + +static int bt_alloc(struct blk_mq_bitmap_tags *bt, unsigned int depth, + int node, bool reserved) +{ + int i; + + bt->bits_per_word = ilog2(BITS_PER_LONG); + + /* + * Depth can be zero for reserved tags, that's not a failure + * condition. + */ + if (depth) { + unsigned int nr, tags_per_word; + + tags_per_word = (1 << bt->bits_per_word); + + /* + * If the tag space is small, shrink the number of tags + * per word so we spread over a few cachelines, at least. + * If less than 4 tags, just forget about it, it's not + * going to work optimally anyway. + */ + if (depth >= 4) { + while (tags_per_word * 4 > depth) { + bt->bits_per_word--; + tags_per_word = (1 << bt->bits_per_word); + } + } + + nr = ALIGN(depth, tags_per_word) / tags_per_word; + bt->map = kzalloc_node(nr * sizeof(struct blk_align_bitmap), + GFP_KERNEL, node); + if (!bt->map) + return -ENOMEM; + + bt->map_nr = nr; + } + + bt->bs = kzalloc(BT_WAIT_QUEUES * sizeof(*bt->bs), GFP_KERNEL); + if (!bt->bs) { + kfree(bt->map); + return -ENOMEM; + } + + bt_update_count(bt, depth); + + for (i = 0; i < BT_WAIT_QUEUES; i++) { + init_waitqueue_head(&bt->bs[i].wait); + atomic_set(&bt->bs[i].wait_cnt, bt->wake_cnt); + } + + return 0; +} + +static void bt_free(struct blk_mq_bitmap_tags *bt) +{ + kfree(bt->map); + kfree(bt->bs); +} + +static struct blk_mq_tags *blk_mq_init_bitmap_tags(struct blk_mq_tags *tags, + int node) +{ + unsigned int depth = tags->nr_tags - tags->nr_reserved_tags; + + if (bt_alloc(&tags->bitmap_tags, depth, node, false)) + goto enomem; + if (bt_alloc(&tags->breserved_tags, tags->nr_reserved_tags, node, true)) + goto enomem; + + return tags; +enomem: + bt_free(&tags->bitmap_tags); + kfree(tags); + return NULL; +} + +struct blk_mq_tags *blk_mq_init_tags(unsigned int total_tags, + unsigned int reserved_tags, int node) +{ + struct blk_mq_tags *tags; + + if (total_tags > BLK_MQ_TAG_MAX) { + pr_err("blk-mq: tag depth too large\n"); + return NULL; + } + + tags = kzalloc_node(sizeof(*tags), GFP_KERNEL, node); + if (!tags) + return NULL; + + tags->nr_tags = total_tags; + tags->nr_reserved_tags = reserved_tags; + + return blk_mq_init_bitmap_tags(tags, node); +} + +void blk_mq_free_tags(struct blk_mq_tags *tags) +{ + bt_free(&tags->bitmap_tags); + bt_free(&tags->breserved_tags); + kfree(tags); +} + +void blk_mq_tag_init_last_tag(struct blk_mq_tags *tags, unsigned int *tag) +{ + unsigned int depth = tags->nr_tags - tags->nr_reserved_tags; + + *tag = prandom_u32() % depth; +} + +int blk_mq_tag_update_depth(struct blk_mq_tags *tags, unsigned int tdepth) +{ + tdepth -= tags->nr_reserved_tags; + if (tdepth > tags->nr_tags) + return -EINVAL; + + /* + * Don't need (or can't) update reserved tags here, they remain + * static and should never need resizing. + */ + bt_update_count(&tags->bitmap_tags, tdepth); + blk_mq_tag_wakeup_all(tags); + return 0; +} + +ssize_t blk_mq_tag_sysfs_show(struct blk_mq_tags *tags, char *page) +{ + char *orig_page = page; + unsigned int free, res; + + if (!tags) + return 0; + + page += sprintf(page, "nr_tags=%u, reserved_tags=%u, " + "bits_per_word=%u\n", + tags->nr_tags, tags->nr_reserved_tags, + tags->bitmap_tags.bits_per_word); + + free = bt_unused_tags(&tags->bitmap_tags); + res = bt_unused_tags(&tags->breserved_tags); + + page += sprintf(page, "nr_free=%u, nr_reserved=%u\n", free, res); + page += sprintf(page, "active_queues=%u\n", atomic_read(&tags->active_queues)); + + return page - orig_page; +} diff --git a/block/blk-mq-tag.h b/block/blk-mq-tag.h new file mode 100644 index 00000000000..6206ed17ef7 --- /dev/null +++ b/block/blk-mq-tag.h @@ -0,0 +1,88 @@ +#ifndef INT_BLK_MQ_TAG_H +#define INT_BLK_MQ_TAG_H + +#include "blk-mq.h" + +enum { + BT_WAIT_QUEUES = 8, + BT_WAIT_BATCH = 8, +}; + +struct bt_wait_state { + atomic_t wait_cnt; + wait_queue_head_t wait; +} ____cacheline_aligned_in_smp; + +#define TAG_TO_INDEX(bt, tag) ((tag) >> (bt)->bits_per_word) +#define TAG_TO_BIT(bt, tag) ((tag) & ((1 << (bt)->bits_per_word) - 1)) + +struct blk_mq_bitmap_tags { + unsigned int depth; + unsigned int wake_cnt; + unsigned int bits_per_word; + + unsigned int map_nr; + struct blk_align_bitmap *map; + + atomic_t wake_index; + struct bt_wait_state *bs; +}; + +/* + * Tag address space map. + */ +struct blk_mq_tags { + unsigned int nr_tags; + unsigned int nr_reserved_tags; + + atomic_t active_queues; + + struct blk_mq_bitmap_tags bitmap_tags; + struct blk_mq_bitmap_tags breserved_tags; + + struct request **rqs; + struct list_head page_list; +}; + + +extern struct blk_mq_tags *blk_mq_init_tags(unsigned int nr_tags, unsigned int reserved_tags, int node); +extern void blk_mq_free_tags(struct blk_mq_tags *tags); + +extern unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data); +extern void blk_mq_put_tag(struct blk_mq_hw_ctx *hctx, unsigned int tag, unsigned int *last_tag); +extern bool blk_mq_has_free_tags(struct blk_mq_tags *tags); +extern ssize_t blk_mq_tag_sysfs_show(struct blk_mq_tags *tags, char *page); +extern void blk_mq_tag_init_last_tag(struct blk_mq_tags *tags, unsigned int *last_tag); +extern int blk_mq_tag_update_depth(struct blk_mq_tags *tags, unsigned int depth); + +enum { + BLK_MQ_TAG_CACHE_MIN = 1, + BLK_MQ_TAG_CACHE_MAX = 64, +}; + +enum { + BLK_MQ_TAG_FAIL = -1U, + BLK_MQ_TAG_MIN = BLK_MQ_TAG_CACHE_MIN, + BLK_MQ_TAG_MAX = BLK_MQ_TAG_FAIL - 1, +}; + +extern bool __blk_mq_tag_busy(struct blk_mq_hw_ctx *); +extern void __blk_mq_tag_idle(struct blk_mq_hw_ctx *); + +static inline bool blk_mq_tag_busy(struct blk_mq_hw_ctx *hctx) +{ + if (!(hctx->flags & BLK_MQ_F_TAG_SHARED)) + return false; + + return __blk_mq_tag_busy(hctx); +} + +static inline void blk_mq_tag_idle(struct blk_mq_hw_ctx *hctx) +{ + if (!(hctx->flags & BLK_MQ_F_TAG_SHARED)) + return; + + __blk_mq_tag_idle(hctx); +} + +#endif diff --git a/block/blk-mq.c b/block/blk-mq.c new file mode 100644 index 00000000000..ad69ef657e8 --- /dev/null +++ b/block/blk-mq.c @@ -0,0 +1,2058 @@ +/* + * Block multiqueue core code + * + * Copyright (C) 2013-2014 Jens Axboe + * Copyright (C) 2013-2014 Christoph Hellwig + */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/backing-dev.h> +#include <linux/bio.h> +#include <linux/blkdev.h> +#include <linux/mm.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/workqueue.h> +#include <linux/smp.h> +#include <linux/llist.h> +#include <linux/list_sort.h> +#include <linux/cpu.h> +#include <linux/cache.h> +#include <linux/sched/sysctl.h> +#include <linux/delay.h> + +#include <trace/events/block.h> + +#include <linux/blk-mq.h> +#include "blk.h" +#include "blk-mq.h" +#include "blk-mq-tag.h" + +static DEFINE_MUTEX(all_q_mutex); +static LIST_HEAD(all_q_list); + +static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx); + +/* + * Check if any of the ctx's have pending work in this hardware queue + */ +static bool blk_mq_hctx_has_pending(struct blk_mq_hw_ctx *hctx) +{ + unsigned int i; + + for (i = 0; i < hctx->ctx_map.map_size; i++) + if (hctx->ctx_map.map[i].word) + return true; + + return false; +} + +static inline struct blk_align_bitmap *get_bm(struct blk_mq_hw_ctx *hctx, + struct blk_mq_ctx *ctx) +{ + return &hctx->ctx_map.map[ctx->index_hw / hctx->ctx_map.bits_per_word]; +} + +#define CTX_TO_BIT(hctx, ctx) \ + ((ctx)->index_hw & ((hctx)->ctx_map.bits_per_word - 1)) + +/* + * Mark this ctx as having pending work in this hardware queue + */ +static void blk_mq_hctx_mark_pending(struct blk_mq_hw_ctx *hctx, + struct blk_mq_ctx *ctx) +{ + struct blk_align_bitmap *bm = get_bm(hctx, ctx); + + if (!test_bit(CTX_TO_BIT(hctx, ctx), &bm->word)) + set_bit(CTX_TO_BIT(hctx, ctx), &bm->word); +} + +static void blk_mq_hctx_clear_pending(struct blk_mq_hw_ctx *hctx, + struct blk_mq_ctx *ctx) +{ + struct blk_align_bitmap *bm = get_bm(hctx, ctx); + + clear_bit(CTX_TO_BIT(hctx, ctx), &bm->word); +} + +static int blk_mq_queue_enter(struct request_queue *q) +{ + int ret; + + __percpu_counter_add(&q->mq_usage_counter, 1, 1000000); + smp_wmb(); + + /* we have problems freezing the queue if it's initializing */ + if (!blk_queue_dying(q) && + (!blk_queue_bypass(q) || !blk_queue_init_done(q))) + return 0; + + __percpu_counter_add(&q->mq_usage_counter, -1, 1000000); + + spin_lock_irq(q->queue_lock); + ret = wait_event_interruptible_lock_irq(q->mq_freeze_wq, + !blk_queue_bypass(q) || blk_queue_dying(q), + *q->queue_lock); + /* inc usage with lock hold to avoid freeze_queue runs here */ + if (!ret && !blk_queue_dying(q)) + __percpu_counter_add(&q->mq_usage_counter, 1, 1000000); + else if (blk_queue_dying(q)) + ret = -ENODEV; + spin_unlock_irq(q->queue_lock); + + return ret; +} + +static void blk_mq_queue_exit(struct request_queue *q) +{ + __percpu_counter_add(&q->mq_usage_counter, -1, 1000000); +} + +void blk_mq_drain_queue(struct request_queue *q) +{ + while (true) { + s64 count; + + spin_lock_irq(q->queue_lock); + count = percpu_counter_sum(&q->mq_usage_counter); + spin_unlock_irq(q->queue_lock); + + if (count == 0) + break; + blk_mq_start_hw_queues(q); + msleep(10); + } +} + +/* + * Guarantee no request is in use, so we can change any data structure of + * the queue afterward. + */ +static void blk_mq_freeze_queue(struct request_queue *q) +{ + bool drain; + + spin_lock_irq(q->queue_lock); + drain = !q->bypass_depth++; + queue_flag_set(QUEUE_FLAG_BYPASS, q); + spin_unlock_irq(q->queue_lock); + + if (drain) + blk_mq_drain_queue(q); +} + +static void blk_mq_unfreeze_queue(struct request_queue *q) +{ + bool wake = false; + + spin_lock_irq(q->queue_lock); + if (!--q->bypass_depth) { + queue_flag_clear(QUEUE_FLAG_BYPASS, q); + wake = true; + } + WARN_ON_ONCE(q->bypass_depth < 0); + spin_unlock_irq(q->queue_lock); + if (wake) + wake_up_all(&q->mq_freeze_wq); +} + +bool blk_mq_can_queue(struct blk_mq_hw_ctx *hctx) +{ + return blk_mq_has_free_tags(hctx->tags); +} +EXPORT_SYMBOL(blk_mq_can_queue); + +static void blk_mq_rq_ctx_init(struct request_queue *q, struct blk_mq_ctx *ctx, + struct request *rq, unsigned int rw_flags) +{ + if (blk_queue_io_stat(q)) + rw_flags |= REQ_IO_STAT; + + INIT_LIST_HEAD(&rq->queuelist); + /* csd/requeue_work/fifo_time is initialized before use */ + rq->q = q; + rq->mq_ctx = ctx; + rq->cmd_flags |= rw_flags; + /* do not touch atomic flags, it needs atomic ops against the timer */ + rq->cpu = -1; + INIT_HLIST_NODE(&rq->hash); + RB_CLEAR_NODE(&rq->rb_node); + rq->rq_disk = NULL; + rq->part = NULL; + rq->start_time = jiffies; +#ifdef CONFIG_BLK_CGROUP + rq->rl = NULL; + set_start_time_ns(rq); + rq->io_start_time_ns = 0; +#endif + rq->nr_phys_segments = 0; +#if defined(CONFIG_BLK_DEV_INTEGRITY) + rq->nr_integrity_segments = 0; +#endif + rq->special = NULL; + /* tag was already set */ + rq->errors = 0; + + rq->extra_len = 0; + rq->sense_len = 0; + rq->resid_len = 0; + rq->sense = NULL; + + INIT_LIST_HEAD(&rq->timeout_list); + rq->timeout = 0; + + rq->end_io = NULL; + rq->end_io_data = NULL; + rq->next_rq = NULL; + + ctx->rq_dispatched[rw_is_sync(rw_flags)]++; +} + +static struct request * +__blk_mq_alloc_request(struct blk_mq_alloc_data *data, int rw) +{ + struct request *rq; + unsigned int tag; + + tag = blk_mq_get_tag(data); + if (tag != BLK_MQ_TAG_FAIL) { + rq = data->hctx->tags->rqs[tag]; + + rq->cmd_flags = 0; + if (blk_mq_tag_busy(data->hctx)) { + rq->cmd_flags = REQ_MQ_INFLIGHT; + atomic_inc(&data->hctx->nr_active); + } + + rq->tag = tag; + blk_mq_rq_ctx_init(data->q, data->ctx, rq, rw); + return rq; + } + + return NULL; +} + +struct request *blk_mq_alloc_request(struct request_queue *q, int rw, gfp_t gfp, + bool reserved) +{ + struct blk_mq_ctx *ctx; + struct blk_mq_hw_ctx *hctx; + struct request *rq; + struct blk_mq_alloc_data alloc_data; + + if (blk_mq_queue_enter(q)) + return NULL; + + ctx = blk_mq_get_ctx(q); + hctx = q->mq_ops->map_queue(q, ctx->cpu); + blk_mq_set_alloc_data(&alloc_data, q, gfp & ~__GFP_WAIT, + reserved, ctx, hctx); + + rq = __blk_mq_alloc_request(&alloc_data, rw); + if (!rq && (gfp & __GFP_WAIT)) { + __blk_mq_run_hw_queue(hctx); + blk_mq_put_ctx(ctx); + + ctx = blk_mq_get_ctx(q); + hctx = q->mq_ops->map_queue(q, ctx->cpu); + blk_mq_set_alloc_data(&alloc_data, q, gfp, reserved, ctx, + hctx); + rq = __blk_mq_alloc_request(&alloc_data, rw); + ctx = alloc_data.ctx; + } + blk_mq_put_ctx(ctx); + return rq; +} +EXPORT_SYMBOL(blk_mq_alloc_request); + +static void __blk_mq_free_request(struct blk_mq_hw_ctx *hctx, + struct blk_mq_ctx *ctx, struct request *rq) +{ + const int tag = rq->tag; + struct request_queue *q = rq->q; + + if (rq->cmd_flags & REQ_MQ_INFLIGHT) + atomic_dec(&hctx->nr_active); + + clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags); + blk_mq_put_tag(hctx, tag, &ctx->last_tag); + blk_mq_queue_exit(q); +} + +void blk_mq_free_request(struct request *rq) +{ + struct blk_mq_ctx *ctx = rq->mq_ctx; + struct blk_mq_hw_ctx *hctx; + struct request_queue *q = rq->q; + + ctx->rq_completed[rq_is_sync(rq)]++; + + hctx = q->mq_ops->map_queue(q, ctx->cpu); + __blk_mq_free_request(hctx, ctx, rq); +} + +/* + * Clone all relevant state from a request that has been put on hold in + * the flush state machine into the preallocated flush request that hangs + * off the request queue. + * + * For a driver the flush request should be invisible, that's why we are + * impersonating the original request here. + */ +void blk_mq_clone_flush_request(struct request *flush_rq, + struct request *orig_rq) +{ + struct blk_mq_hw_ctx *hctx = + orig_rq->q->mq_ops->map_queue(orig_rq->q, orig_rq->mq_ctx->cpu); + + flush_rq->mq_ctx = orig_rq->mq_ctx; + flush_rq->tag = orig_rq->tag; + memcpy(blk_mq_rq_to_pdu(flush_rq), blk_mq_rq_to_pdu(orig_rq), + hctx->cmd_size); +} + +inline void __blk_mq_end_io(struct request *rq, int error) +{ + blk_account_io_done(rq); + + if (rq->end_io) { + rq->end_io(rq, error); + } else { + if (unlikely(blk_bidi_rq(rq))) + blk_mq_free_request(rq->next_rq); + blk_mq_free_request(rq); + } +} +EXPORT_SYMBOL(__blk_mq_end_io); + +void blk_mq_end_io(struct request *rq, int error) +{ + if (blk_update_request(rq, error, blk_rq_bytes(rq))) + BUG(); + __blk_mq_end_io(rq, error); +} +EXPORT_SYMBOL(blk_mq_end_io); + +static void __blk_mq_complete_request_remote(void *data) +{ + struct request *rq = data; + + rq->q->softirq_done_fn(rq); +} + +static void blk_mq_ipi_complete_request(struct request *rq) +{ + struct blk_mq_ctx *ctx = rq->mq_ctx; + bool shared = false; + int cpu; + + if (!test_bit(QUEUE_FLAG_SAME_COMP, &rq->q->queue_flags)) { + rq->q->softirq_done_fn(rq); + return; + } + + cpu = get_cpu(); + if (!test_bit(QUEUE_FLAG_SAME_FORCE, &rq->q->queue_flags)) + shared = cpus_share_cache(cpu, ctx->cpu); + + if (cpu != ctx->cpu && !shared && cpu_online(ctx->cpu)) { + rq->csd.func = __blk_mq_complete_request_remote; + rq->csd.info = rq; + rq->csd.flags = 0; + smp_call_function_single_async(ctx->cpu, &rq->csd); + } else { + rq->q->softirq_done_fn(rq); + } + put_cpu(); +} + +void __blk_mq_complete_request(struct request *rq) +{ + struct request_queue *q = rq->q; + + if (!q->softirq_done_fn) + blk_mq_end_io(rq, rq->errors); + else + blk_mq_ipi_complete_request(rq); +} + +/** + * blk_mq_complete_request - end I/O on a request + * @rq: the request being processed + * + * Description: + * Ends all I/O on a request. It does not handle partial completions. + * The actual completion happens out-of-order, through a IPI handler. + **/ +void blk_mq_complete_request(struct request *rq) +{ + struct request_queue *q = rq->q; + + if (unlikely(blk_should_fake_timeout(q))) + return; + if (!blk_mark_rq_complete(rq)) + __blk_mq_complete_request(rq); +} +EXPORT_SYMBOL(blk_mq_complete_request); + +static void blk_mq_start_request(struct request *rq, bool last) +{ + struct request_queue *q = rq->q; + + trace_block_rq_issue(q, rq); + + rq->resid_len = blk_rq_bytes(rq); + if (unlikely(blk_bidi_rq(rq))) + rq->next_rq->resid_len = blk_rq_bytes(rq->next_rq); + + blk_add_timer(rq); + + /* + * Mark us as started and clear complete. Complete might have been + * set if requeue raced with timeout, which then marked it as + * complete. So be sure to clear complete again when we start + * the request, otherwise we'll ignore the completion event. + */ + if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) + set_bit(REQ_ATOM_STARTED, &rq->atomic_flags); + if (test_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags)) + clear_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags); + + if (q->dma_drain_size && blk_rq_bytes(rq)) { + /* + * Make sure space for the drain appears. We know we can do + * this because max_hw_segments has been adjusted to be one + * fewer than the device can handle. + */ + rq->nr_phys_segments++; + } + + /* + * Flag the last request in the series so that drivers know when IO + * should be kicked off, if they don't do it on a per-request basis. + * + * Note: the flag isn't the only condition drivers should do kick off. + * If drive is busy, the last request might not have the bit set. + */ + if (last) + rq->cmd_flags |= REQ_END; +} + +static void __blk_mq_requeue_request(struct request *rq) +{ + struct request_queue *q = rq->q; + + trace_block_rq_requeue(q, rq); + clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags); + + rq->cmd_flags &= ~REQ_END; + + if (q->dma_drain_size && blk_rq_bytes(rq)) + rq->nr_phys_segments--; +} + +void blk_mq_requeue_request(struct request *rq) +{ + __blk_mq_requeue_request(rq); + blk_clear_rq_complete(rq); + + BUG_ON(blk_queued_rq(rq)); + blk_mq_add_to_requeue_list(rq, true); +} +EXPORT_SYMBOL(blk_mq_requeue_request); + +static void blk_mq_requeue_work(struct work_struct *work) +{ + struct request_queue *q = + container_of(work, struct request_queue, requeue_work); + LIST_HEAD(rq_list); + struct request *rq, *next; + unsigned long flags; + + spin_lock_irqsave(&q->requeue_lock, flags); + list_splice_init(&q->requeue_list, &rq_list); + spin_unlock_irqrestore(&q->requeue_lock, flags); + + list_for_each_entry_safe(rq, next, &rq_list, queuelist) { + if (!(rq->cmd_flags & REQ_SOFTBARRIER)) + continue; + + rq->cmd_flags &= ~REQ_SOFTBARRIER; + list_del_init(&rq->queuelist); + blk_mq_insert_request(rq, true, false, false); + } + + while (!list_empty(&rq_list)) { + rq = list_entry(rq_list.next, struct request, queuelist); + list_del_init(&rq->queuelist); + blk_mq_insert_request(rq, false, false, false); + } + + blk_mq_run_queues(q, false); +} + +void blk_mq_add_to_requeue_list(struct request *rq, bool at_head) +{ + struct request_queue *q = rq->q; + unsigned long flags; + + /* + * We abuse this flag that is otherwise used by the I/O scheduler to + * request head insertation from the workqueue. + */ + BUG_ON(rq->cmd_flags & REQ_SOFTBARRIER); + + spin_lock_irqsave(&q->requeue_lock, flags); + if (at_head) { + rq->cmd_flags |= REQ_SOFTBARRIER; + list_add(&rq->queuelist, &q->requeue_list); + } else { + list_add_tail(&rq->queuelist, &q->requeue_list); + } + spin_unlock_irqrestore(&q->requeue_lock, flags); +} +EXPORT_SYMBOL(blk_mq_add_to_requeue_list); + +void blk_mq_kick_requeue_list(struct request_queue *q) +{ + kblockd_schedule_work(&q->requeue_work); +} +EXPORT_SYMBOL(blk_mq_kick_requeue_list); + +static inline bool is_flush_request(struct request *rq, unsigned int tag) +{ + return ((rq->cmd_flags & REQ_FLUSH_SEQ) && + rq->q->flush_rq->tag == tag); +} + +struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag) +{ + struct request *rq = tags->rqs[tag]; + + if (!is_flush_request(rq, tag)) + return rq; + + return rq->q->flush_rq; +} +EXPORT_SYMBOL(blk_mq_tag_to_rq); + +struct blk_mq_timeout_data { + struct blk_mq_hw_ctx *hctx; + unsigned long *next; + unsigned int *next_set; +}; + +static void blk_mq_timeout_check(void *__data, unsigned long *free_tags) +{ + struct blk_mq_timeout_data *data = __data; + struct blk_mq_hw_ctx *hctx = data->hctx; + unsigned int tag; + + /* It may not be in flight yet (this is where + * the REQ_ATOMIC_STARTED flag comes in). The requests are + * statically allocated, so we know it's always safe to access the + * memory associated with a bit offset into ->rqs[]. + */ + tag = 0; + do { + struct request *rq; + + tag = find_next_zero_bit(free_tags, hctx->tags->nr_tags, tag); + if (tag >= hctx->tags->nr_tags) + break; + + rq = blk_mq_tag_to_rq(hctx->tags, tag++); + if (rq->q != hctx->queue) + continue; + if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) + continue; + + blk_rq_check_expired(rq, data->next, data->next_set); + } while (1); +} + +static void blk_mq_hw_ctx_check_timeout(struct blk_mq_hw_ctx *hctx, + unsigned long *next, + unsigned int *next_set) +{ + struct blk_mq_timeout_data data = { + .hctx = hctx, + .next = next, + .next_set = next_set, + }; + + /* + * Ask the tagging code to iterate busy requests, so we can + * check them for timeout. + */ + blk_mq_tag_busy_iter(hctx->tags, blk_mq_timeout_check, &data); +} + +static enum blk_eh_timer_return blk_mq_rq_timed_out(struct request *rq) +{ + struct request_queue *q = rq->q; + + /* + * We know that complete is set at this point. If STARTED isn't set + * anymore, then the request isn't active and the "timeout" should + * just be ignored. This can happen due to the bitflag ordering. + * Timeout first checks if STARTED is set, and if it is, assumes + * the request is active. But if we race with completion, then + * we both flags will get cleared. So check here again, and ignore + * a timeout event with a request that isn't active. + */ + if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) + return BLK_EH_NOT_HANDLED; + + if (!q->mq_ops->timeout) + return BLK_EH_RESET_TIMER; + + return q->mq_ops->timeout(rq); +} + +static void blk_mq_rq_timer(unsigned long data) +{ + struct request_queue *q = (struct request_queue *) data; + struct blk_mq_hw_ctx *hctx; + unsigned long next = 0; + int i, next_set = 0; + + queue_for_each_hw_ctx(q, hctx, i) { + /* + * If not software queues are currently mapped to this + * hardware queue, there's nothing to check + */ + if (!hctx->nr_ctx || !hctx->tags) + continue; + + blk_mq_hw_ctx_check_timeout(hctx, &next, &next_set); + } + + if (next_set) { + next = blk_rq_timeout(round_jiffies_up(next)); + mod_timer(&q->timeout, next); + } else { + queue_for_each_hw_ctx(q, hctx, i) + blk_mq_tag_idle(hctx); + } +} + +/* + * Reverse check our software queue for entries that we could potentially + * merge with. Currently includes a hand-wavy stop count of 8, to not spend + * too much time checking for merges. + */ +static bool blk_mq_attempt_merge(struct request_queue *q, + struct blk_mq_ctx *ctx, struct bio *bio) +{ + struct request *rq; + int checked = 8; + + list_for_each_entry_reverse(rq, &ctx->rq_list, queuelist) { + int el_ret; + + if (!checked--) + break; + + if (!blk_rq_merge_ok(rq, bio)) + continue; + + el_ret = blk_try_merge(rq, bio); + if (el_ret == ELEVATOR_BACK_MERGE) { + if (bio_attempt_back_merge(q, rq, bio)) { + ctx->rq_merged++; + return true; + } + break; + } else if (el_ret == ELEVATOR_FRONT_MERGE) { + if (bio_attempt_front_merge(q, rq, bio)) { + ctx->rq_merged++; + return true; + } + break; + } + } + + return false; +} + +/* + * Process software queues that have been marked busy, splicing them + * to the for-dispatch + */ +static void flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list) +{ + struct blk_mq_ctx *ctx; + int i; + + for (i = 0; i < hctx->ctx_map.map_size; i++) { + struct blk_align_bitmap *bm = &hctx->ctx_map.map[i]; + unsigned int off, bit; + + if (!bm->word) + continue; + + bit = 0; + off = i * hctx->ctx_map.bits_per_word; + do { + bit = find_next_bit(&bm->word, bm->depth, bit); + if (bit >= bm->depth) + break; + + ctx = hctx->ctxs[bit + off]; + clear_bit(bit, &bm->word); + spin_lock(&ctx->lock); + list_splice_tail_init(&ctx->rq_list, list); + spin_unlock(&ctx->lock); + + bit++; + } while (1); + } +} + +/* + * Run this hardware queue, pulling any software queues mapped to it in. + * Note that this function currently has various problems around ordering + * of IO. In particular, we'd like FIFO behaviour on handling existing + * items on the hctx->dispatch list. Ignore that for now. + */ +static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx) +{ + struct request_queue *q = hctx->queue; + struct request *rq; + LIST_HEAD(rq_list); + int queued; + + WARN_ON(!cpumask_test_cpu(raw_smp_processor_id(), hctx->cpumask)); + + if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state))) + return; + + hctx->run++; + + /* + * Touch any software queue that has pending entries. + */ + flush_busy_ctxs(hctx, &rq_list); + + /* + * If we have previous entries on our dispatch list, grab them + * and stuff them at the front for more fair dispatch. + */ + if (!list_empty_careful(&hctx->dispatch)) { + spin_lock(&hctx->lock); + if (!list_empty(&hctx->dispatch)) + list_splice_init(&hctx->dispatch, &rq_list); + spin_unlock(&hctx->lock); + } + + /* + * Now process all the entries, sending them to the driver. + */ + queued = 0; + while (!list_empty(&rq_list)) { + int ret; + + rq = list_first_entry(&rq_list, struct request, queuelist); + list_del_init(&rq->queuelist); + + blk_mq_start_request(rq, list_empty(&rq_list)); + + ret = q->mq_ops->queue_rq(hctx, rq); + switch (ret) { + case BLK_MQ_RQ_QUEUE_OK: + queued++; + continue; + case BLK_MQ_RQ_QUEUE_BUSY: + list_add(&rq->queuelist, &rq_list); + __blk_mq_requeue_request(rq); + break; + default: + pr_err("blk-mq: bad return on queue: %d\n", ret); + case BLK_MQ_RQ_QUEUE_ERROR: + rq->errors = -EIO; + blk_mq_end_io(rq, rq->errors); + break; + } + + if (ret == BLK_MQ_RQ_QUEUE_BUSY) + break; + } + + if (!queued) + hctx->dispatched[0]++; + else if (queued < (1 << (BLK_MQ_MAX_DISPATCH_ORDER - 1))) + hctx->dispatched[ilog2(queued) + 1]++; + + /* + * Any items that need requeuing? Stuff them into hctx->dispatch, + * that is where we will continue on next queue run. + */ + if (!list_empty(&rq_list)) { + spin_lock(&hctx->lock); + list_splice(&rq_list, &hctx->dispatch); + spin_unlock(&hctx->lock); + } +} + +/* + * It'd be great if the workqueue API had a way to pass + * in a mask and had some smarts for more clever placement. + * For now we just round-robin here, switching for every + * BLK_MQ_CPU_WORK_BATCH queued items. + */ +static int blk_mq_hctx_next_cpu(struct blk_mq_hw_ctx *hctx) +{ + int cpu = hctx->next_cpu; + + if (--hctx->next_cpu_batch <= 0) { + int next_cpu; + + next_cpu = cpumask_next(hctx->next_cpu, hctx->cpumask); + if (next_cpu >= nr_cpu_ids) + next_cpu = cpumask_first(hctx->cpumask); + + hctx->next_cpu = next_cpu; + hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; + } + + return cpu; +} + +void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async) +{ + if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state))) + return; + + if (!async && cpumask_test_cpu(smp_processor_id(), hctx->cpumask)) + __blk_mq_run_hw_queue(hctx); + else if (hctx->queue->nr_hw_queues == 1) + kblockd_schedule_delayed_work(&hctx->run_work, 0); + else { + unsigned int cpu; + + cpu = blk_mq_hctx_next_cpu(hctx); + kblockd_schedule_delayed_work_on(cpu, &hctx->run_work, 0); + } +} + +void blk_mq_run_queues(struct request_queue *q, bool async) +{ + struct blk_mq_hw_ctx *hctx; + int i; + + queue_for_each_hw_ctx(q, hctx, i) { + if ((!blk_mq_hctx_has_pending(hctx) && + list_empty_careful(&hctx->dispatch)) || + test_bit(BLK_MQ_S_STOPPED, &hctx->state)) + continue; + + preempt_disable(); + blk_mq_run_hw_queue(hctx, async); + preempt_enable(); + } +} +EXPORT_SYMBOL(blk_mq_run_queues); + +void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx) +{ + cancel_delayed_work(&hctx->run_work); + cancel_delayed_work(&hctx->delay_work); + set_bit(BLK_MQ_S_STOPPED, &hctx->state); +} +EXPORT_SYMBOL(blk_mq_stop_hw_queue); + +void blk_mq_stop_hw_queues(struct request_queue *q) +{ + struct blk_mq_hw_ctx *hctx; + int i; + + queue_for_each_hw_ctx(q, hctx, i) + blk_mq_stop_hw_queue(hctx); +} +EXPORT_SYMBOL(blk_mq_stop_hw_queues); + +void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx) +{ + clear_bit(BLK_MQ_S_STOPPED, &hctx->state); + + preempt_disable(); + blk_mq_run_hw_queue(hctx, false); + preempt_enable(); +} +EXPORT_SYMBOL(blk_mq_start_hw_queue); + +void blk_mq_start_hw_queues(struct request_queue *q) +{ + struct blk_mq_hw_ctx *hctx; + int i; + + queue_for_each_hw_ctx(q, hctx, i) + blk_mq_start_hw_queue(hctx); +} +EXPORT_SYMBOL(blk_mq_start_hw_queues); + + +void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async) +{ + struct blk_mq_hw_ctx *hctx; + int i; + + queue_for_each_hw_ctx(q, hctx, i) { + if (!test_bit(BLK_MQ_S_STOPPED, &hctx->state)) + continue; + + clear_bit(BLK_MQ_S_STOPPED, &hctx->state); + preempt_disable(); + blk_mq_run_hw_queue(hctx, async); + preempt_enable(); + } +} +EXPORT_SYMBOL(blk_mq_start_stopped_hw_queues); + +static void blk_mq_run_work_fn(struct work_struct *work) +{ + struct blk_mq_hw_ctx *hctx; + + hctx = container_of(work, struct blk_mq_hw_ctx, run_work.work); + + __blk_mq_run_hw_queue(hctx); +} + +static void blk_mq_delay_work_fn(struct work_struct *work) +{ + struct blk_mq_hw_ctx *hctx; + + hctx = container_of(work, struct blk_mq_hw_ctx, delay_work.work); + + if (test_and_clear_bit(BLK_MQ_S_STOPPED, &hctx->state)) + __blk_mq_run_hw_queue(hctx); +} + +void blk_mq_delay_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs) +{ + unsigned long tmo = msecs_to_jiffies(msecs); + + if (hctx->queue->nr_hw_queues == 1) + kblockd_schedule_delayed_work(&hctx->delay_work, tmo); + else { + unsigned int cpu; + + cpu = blk_mq_hctx_next_cpu(hctx); + kblockd_schedule_delayed_work_on(cpu, &hctx->delay_work, tmo); + } +} +EXPORT_SYMBOL(blk_mq_delay_queue); + +static void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, + struct request *rq, bool at_head) +{ + struct blk_mq_ctx *ctx = rq->mq_ctx; + + trace_block_rq_insert(hctx->queue, rq); + + if (at_head) + list_add(&rq->queuelist, &ctx->rq_list); + else + list_add_tail(&rq->queuelist, &ctx->rq_list); + + blk_mq_hctx_mark_pending(hctx, ctx); +} + +void blk_mq_insert_request(struct request *rq, bool at_head, bool run_queue, + bool async) +{ + struct request_queue *q = rq->q; + struct blk_mq_hw_ctx *hctx; + struct blk_mq_ctx *ctx = rq->mq_ctx, *current_ctx; + + current_ctx = blk_mq_get_ctx(q); + if (!cpu_online(ctx->cpu)) + rq->mq_ctx = ctx = current_ctx; + + hctx = q->mq_ops->map_queue(q, ctx->cpu); + + if (rq->cmd_flags & (REQ_FLUSH | REQ_FUA) && + !(rq->cmd_flags & (REQ_FLUSH_SEQ))) { + blk_insert_flush(rq); + } else { + spin_lock(&ctx->lock); + __blk_mq_insert_request(hctx, rq, at_head); + spin_unlock(&ctx->lock); + } + + if (run_queue) + blk_mq_run_hw_queue(hctx, async); + + blk_mq_put_ctx(current_ctx); +} + +static void blk_mq_insert_requests(struct request_queue *q, + struct blk_mq_ctx *ctx, + struct list_head *list, + int depth, + bool from_schedule) + +{ + struct blk_mq_hw_ctx *hctx; + struct blk_mq_ctx *current_ctx; + + trace_block_unplug(q, depth, !from_schedule); + + current_ctx = blk_mq_get_ctx(q); + + if (!cpu_online(ctx->cpu)) + ctx = current_ctx; + hctx = q->mq_ops->map_queue(q, ctx->cpu); + + /* + * preemption doesn't flush plug list, so it's possible ctx->cpu is + * offline now + */ + spin_lock(&ctx->lock); + while (!list_empty(list)) { + struct request *rq; + + rq = list_first_entry(list, struct request, queuelist); + list_del_init(&rq->queuelist); + rq->mq_ctx = ctx; + __blk_mq_insert_request(hctx, rq, false); + } + spin_unlock(&ctx->lock); + + blk_mq_run_hw_queue(hctx, from_schedule); + blk_mq_put_ctx(current_ctx); +} + +static int plug_ctx_cmp(void *priv, struct list_head *a, struct list_head *b) +{ + struct request *rqa = container_of(a, struct request, queuelist); + struct request *rqb = container_of(b, struct request, queuelist); + + return !(rqa->mq_ctx < rqb->mq_ctx || + (rqa->mq_ctx == rqb->mq_ctx && + blk_rq_pos(rqa) < blk_rq_pos(rqb))); +} + +void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) +{ + struct blk_mq_ctx *this_ctx; + struct request_queue *this_q; + struct request *rq; + LIST_HEAD(list); + LIST_HEAD(ctx_list); + unsigned int depth; + + list_splice_init(&plug->mq_list, &list); + + list_sort(NULL, &list, plug_ctx_cmp); + + this_q = NULL; + this_ctx = NULL; + depth = 0; + + while (!list_empty(&list)) { + rq = list_entry_rq(list.next); + list_del_init(&rq->queuelist); + BUG_ON(!rq->q); + if (rq->mq_ctx != this_ctx) { + if (this_ctx) { + blk_mq_insert_requests(this_q, this_ctx, + &ctx_list, depth, + from_schedule); + } + + this_ctx = rq->mq_ctx; + this_q = rq->q; + depth = 0; + } + + depth++; + list_add_tail(&rq->queuelist, &ctx_list); + } + + /* + * If 'this_ctx' is set, we know we have entries to complete + * on 'ctx_list'. Do those. + */ + if (this_ctx) { + blk_mq_insert_requests(this_q, this_ctx, &ctx_list, depth, + from_schedule); + } +} + +static void blk_mq_bio_to_request(struct request *rq, struct bio *bio) +{ + init_request_from_bio(rq, bio); + + if (blk_do_io_stat(rq)) + blk_account_io_start(rq, 1); +} + +static inline bool blk_mq_merge_queue_io(struct blk_mq_hw_ctx *hctx, + struct blk_mq_ctx *ctx, + struct request *rq, struct bio *bio) +{ + struct request_queue *q = hctx->queue; + + if (!(hctx->flags & BLK_MQ_F_SHOULD_MERGE)) { + blk_mq_bio_to_request(rq, bio); + spin_lock(&ctx->lock); +insert_rq: + __blk_mq_insert_request(hctx, rq, false); + spin_unlock(&ctx->lock); + return false; + } else { + spin_lock(&ctx->lock); + if (!blk_mq_attempt_merge(q, ctx, bio)) { + blk_mq_bio_to_request(rq, bio); + goto insert_rq; + } + + spin_unlock(&ctx->lock); + __blk_mq_free_request(hctx, ctx, rq); + return true; + } +} + +struct blk_map_ctx { + struct blk_mq_hw_ctx *hctx; + struct blk_mq_ctx *ctx; +}; + +static struct request *blk_mq_map_request(struct request_queue *q, + struct bio *bio, + struct blk_map_ctx *data) +{ + struct blk_mq_hw_ctx *hctx; + struct blk_mq_ctx *ctx; + struct request *rq; + int rw = bio_data_dir(bio); + struct blk_mq_alloc_data alloc_data; + + if (unlikely(blk_mq_queue_enter(q))) { + bio_endio(bio, -EIO); + return NULL; + } + + ctx = blk_mq_get_ctx(q); + hctx = q->mq_ops->map_queue(q, ctx->cpu); + + if (rw_is_sync(bio->bi_rw)) + rw |= REQ_SYNC; + + trace_block_getrq(q, bio, rw); + blk_mq_set_alloc_data(&alloc_data, q, GFP_ATOMIC, false, ctx, + hctx); + rq = __blk_mq_alloc_request(&alloc_data, rw); + if (unlikely(!rq)) { + __blk_mq_run_hw_queue(hctx); + blk_mq_put_ctx(ctx); + trace_block_sleeprq(q, bio, rw); + + ctx = blk_mq_get_ctx(q); + hctx = q->mq_ops->map_queue(q, ctx->cpu); + blk_mq_set_alloc_data(&alloc_data, q, + __GFP_WAIT|GFP_ATOMIC, false, ctx, hctx); + rq = __blk_mq_alloc_request(&alloc_data, rw); + ctx = alloc_data.ctx; + hctx = alloc_data.hctx; + } + + hctx->queued++; + data->hctx = hctx; + data->ctx = ctx; + return rq; +} + +/* + * Multiple hardware queue variant. This will not use per-process plugs, + * but will attempt to bypass the hctx queueing if we can go straight to + * hardware for SYNC IO. + */ +static void blk_mq_make_request(struct request_queue *q, struct bio *bio) +{ + const int is_sync = rw_is_sync(bio->bi_rw); + const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA); + struct blk_map_ctx data; + struct request *rq; + + blk_queue_bounce(q, &bio); + + if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { + bio_endio(bio, -EIO); + return; + } + + rq = blk_mq_map_request(q, bio, &data); + if (unlikely(!rq)) + return; + + if (unlikely(is_flush_fua)) { + blk_mq_bio_to_request(rq, bio); + blk_insert_flush(rq); + goto run_queue; + } + + if (is_sync) { + int ret; + + blk_mq_bio_to_request(rq, bio); + blk_mq_start_request(rq, true); + + /* + * For OK queue, we are done. For error, kill it. Any other + * error (busy), just add it to our list as we previously + * would have done + */ + ret = q->mq_ops->queue_rq(data.hctx, rq); + if (ret == BLK_MQ_RQ_QUEUE_OK) + goto done; + else { + __blk_mq_requeue_request(rq); + + if (ret == BLK_MQ_RQ_QUEUE_ERROR) { + rq->errors = -EIO; + blk_mq_end_io(rq, rq->errors); + goto done; + } + } + } + + if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) { + /* + * For a SYNC request, send it to the hardware immediately. For + * an ASYNC request, just ensure that we run it later on. The + * latter allows for merging opportunities and more efficient + * dispatching. + */ +run_queue: + blk_mq_run_hw_queue(data.hctx, !is_sync || is_flush_fua); + } +done: + blk_mq_put_ctx(data.ctx); +} + +/* + * Single hardware queue variant. This will attempt to use any per-process + * plug for merging and IO deferral. + */ +static void blk_sq_make_request(struct request_queue *q, struct bio *bio) +{ + const int is_sync = rw_is_sync(bio->bi_rw); + const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA); + unsigned int use_plug, request_count = 0; + struct blk_map_ctx data; + struct request *rq; + + /* + * If we have multiple hardware queues, just go directly to + * one of those for sync IO. + */ + use_plug = !is_flush_fua && !is_sync; + + blk_queue_bounce(q, &bio); + + if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { + bio_endio(bio, -EIO); + return; + } + + if (use_plug && !blk_queue_nomerges(q) && + blk_attempt_plug_merge(q, bio, &request_count)) + return; + + rq = blk_mq_map_request(q, bio, &data); + if (unlikely(!rq)) + return; + + if (unlikely(is_flush_fua)) { + blk_mq_bio_to_request(rq, bio); + blk_insert_flush(rq); + goto run_queue; + } + + /* + * A task plug currently exists. Since this is completely lockless, + * utilize that to temporarily store requests until the task is + * either done or scheduled away. + */ + if (use_plug) { + struct blk_plug *plug = current->plug; + + if (plug) { + blk_mq_bio_to_request(rq, bio); + if (list_empty(&plug->mq_list)) + trace_block_plug(q); + else if (request_count >= BLK_MAX_REQUEST_COUNT) { + blk_flush_plug_list(plug, false); + trace_block_plug(q); + } + list_add_tail(&rq->queuelist, &plug->mq_list); + blk_mq_put_ctx(data.ctx); + return; + } + } + + if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) { + /* + * For a SYNC request, send it to the hardware immediately. For + * an ASYNC request, just ensure that we run it later on. The + * latter allows for merging opportunities and more efficient + * dispatching. + */ +run_queue: + blk_mq_run_hw_queue(data.hctx, !is_sync || is_flush_fua); + } + + blk_mq_put_ctx(data.ctx); +} + +/* + * Default mapping to a software queue, since we use one per CPU. + */ +struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q, const int cpu) +{ + return q->queue_hw_ctx[q->mq_map[cpu]]; +} +EXPORT_SYMBOL(blk_mq_map_queue); + +static void blk_mq_free_rq_map(struct blk_mq_tag_set *set, + struct blk_mq_tags *tags, unsigned int hctx_idx) +{ + struct page *page; + + if (tags->rqs && set->ops->exit_request) { + int i; + + for (i = 0; i < tags->nr_tags; i++) { + if (!tags->rqs[i]) + continue; + set->ops->exit_request(set->driver_data, tags->rqs[i], + hctx_idx, i); + } + } + + while (!list_empty(&tags->page_list)) { + page = list_first_entry(&tags->page_list, struct page, lru); + list_del_init(&page->lru); + __free_pages(page, page->private); + } + + kfree(tags->rqs); + + blk_mq_free_tags(tags); +} + +static size_t order_to_size(unsigned int order) +{ + return (size_t)PAGE_SIZE << order; +} + +static struct blk_mq_tags *blk_mq_init_rq_map(struct blk_mq_tag_set *set, + unsigned int hctx_idx) +{ + struct blk_mq_tags *tags; + unsigned int i, j, entries_per_page, max_order = 4; + size_t rq_size, left; + + tags = blk_mq_init_tags(set->queue_depth, set->reserved_tags, + set->numa_node); + if (!tags) + return NULL; + + INIT_LIST_HEAD(&tags->page_list); + + tags->rqs = kmalloc_node(set->queue_depth * sizeof(struct request *), + GFP_KERNEL, set->numa_node); + if (!tags->rqs) { + blk_mq_free_tags(tags); + return NULL; + } + + /* + * rq_size is the size of the request plus driver payload, rounded + * to the cacheline size + */ + rq_size = round_up(sizeof(struct request) + set->cmd_size, + cache_line_size()); + left = rq_size * set->queue_depth; + + for (i = 0; i < set->queue_depth; ) { + int this_order = max_order; + struct page *page; + int to_do; + void *p; + + while (left < order_to_size(this_order - 1) && this_order) + this_order--; + + do { + page = alloc_pages_node(set->numa_node, GFP_KERNEL, + this_order); + if (page) + break; + if (!this_order--) + break; + if (order_to_size(this_order) < rq_size) + break; + } while (1); + + if (!page) + goto fail; + + page->private = this_order; + list_add_tail(&page->lru, &tags->page_list); + + p = page_address(page); + entries_per_page = order_to_size(this_order) / rq_size; + to_do = min(entries_per_page, set->queue_depth - i); + left -= to_do * rq_size; + for (j = 0; j < to_do; j++) { + tags->rqs[i] = p; + if (set->ops->init_request) { + if (set->ops->init_request(set->driver_data, + tags->rqs[i], hctx_idx, i, + set->numa_node)) + goto fail; + } + + p += rq_size; + i++; + } + } + + return tags; + +fail: + pr_warn("%s: failed to allocate requests\n", __func__); + blk_mq_free_rq_map(set, tags, hctx_idx); + return NULL; +} + +static void blk_mq_free_bitmap(struct blk_mq_ctxmap *bitmap) +{ + kfree(bitmap->map); +} + +static int blk_mq_alloc_bitmap(struct blk_mq_ctxmap *bitmap, int node) +{ + unsigned int bpw = 8, total, num_maps, i; + + bitmap->bits_per_word = bpw; + + num_maps = ALIGN(nr_cpu_ids, bpw) / bpw; + bitmap->map = kzalloc_node(num_maps * sizeof(struct blk_align_bitmap), + GFP_KERNEL, node); + if (!bitmap->map) + return -ENOMEM; + + bitmap->map_size = num_maps; + + total = nr_cpu_ids; + for (i = 0; i < num_maps; i++) { + bitmap->map[i].depth = min(total, bitmap->bits_per_word); + total -= bitmap->map[i].depth; + } + + return 0; +} + +static int blk_mq_hctx_cpu_offline(struct blk_mq_hw_ctx *hctx, int cpu) +{ + struct request_queue *q = hctx->queue; + struct blk_mq_ctx *ctx; + LIST_HEAD(tmp); + + /* + * Move ctx entries to new CPU, if this one is going away. + */ + ctx = __blk_mq_get_ctx(q, cpu); + + spin_lock(&ctx->lock); + if (!list_empty(&ctx->rq_list)) { + list_splice_init(&ctx->rq_list, &tmp); + blk_mq_hctx_clear_pending(hctx, ctx); + } + spin_unlock(&ctx->lock); + + if (list_empty(&tmp)) + return NOTIFY_OK; + + ctx = blk_mq_get_ctx(q); + spin_lock(&ctx->lock); + + while (!list_empty(&tmp)) { + struct request *rq; + + rq = list_first_entry(&tmp, struct request, queuelist); + rq->mq_ctx = ctx; + list_move_tail(&rq->queuelist, &ctx->rq_list); + } + + hctx = q->mq_ops->map_queue(q, ctx->cpu); + blk_mq_hctx_mark_pending(hctx, ctx); + + spin_unlock(&ctx->lock); + + blk_mq_run_hw_queue(hctx, true); + blk_mq_put_ctx(ctx); + return NOTIFY_OK; +} + +static int blk_mq_hctx_cpu_online(struct blk_mq_hw_ctx *hctx, int cpu) +{ + struct request_queue *q = hctx->queue; + struct blk_mq_tag_set *set = q->tag_set; + + if (set->tags[hctx->queue_num]) + return NOTIFY_OK; + + set->tags[hctx->queue_num] = blk_mq_init_rq_map(set, hctx->queue_num); + if (!set->tags[hctx->queue_num]) + return NOTIFY_STOP; + + hctx->tags = set->tags[hctx->queue_num]; + return NOTIFY_OK; +} + +static int blk_mq_hctx_notify(void *data, unsigned long action, + unsigned int cpu) +{ + struct blk_mq_hw_ctx *hctx = data; + + if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) + return blk_mq_hctx_cpu_offline(hctx, cpu); + else if (action == CPU_ONLINE || action == CPU_ONLINE_FROZEN) + return blk_mq_hctx_cpu_online(hctx, cpu); + + return NOTIFY_OK; +} + +static void blk_mq_exit_hw_queues(struct request_queue *q, + struct blk_mq_tag_set *set, int nr_queue) +{ + struct blk_mq_hw_ctx *hctx; + unsigned int i; + + queue_for_each_hw_ctx(q, hctx, i) { + if (i == nr_queue) + break; + + blk_mq_tag_idle(hctx); + + if (set->ops->exit_hctx) + set->ops->exit_hctx(hctx, i); + + blk_mq_unregister_cpu_notifier(&hctx->cpu_notifier); + kfree(hctx->ctxs); + blk_mq_free_bitmap(&hctx->ctx_map); + } + +} + +static void blk_mq_free_hw_queues(struct request_queue *q, + struct blk_mq_tag_set *set) +{ + struct blk_mq_hw_ctx *hctx; + unsigned int i; + + queue_for_each_hw_ctx(q, hctx, i) { + free_cpumask_var(hctx->cpumask); + kfree(hctx); + } +} + +static int blk_mq_init_hw_queues(struct request_queue *q, + struct blk_mq_tag_set *set) +{ + struct blk_mq_hw_ctx *hctx; + unsigned int i; + + /* + * Initialize hardware queues + */ + queue_for_each_hw_ctx(q, hctx, i) { + int node; + + node = hctx->numa_node; + if (node == NUMA_NO_NODE) + node = hctx->numa_node = set->numa_node; + + INIT_DELAYED_WORK(&hctx->run_work, blk_mq_run_work_fn); + INIT_DELAYED_WORK(&hctx->delay_work, blk_mq_delay_work_fn); + spin_lock_init(&hctx->lock); + INIT_LIST_HEAD(&hctx->dispatch); + hctx->queue = q; + hctx->queue_num = i; + hctx->flags = set->flags; + hctx->cmd_size = set->cmd_size; + + blk_mq_init_cpu_notifier(&hctx->cpu_notifier, + blk_mq_hctx_notify, hctx); + blk_mq_register_cpu_notifier(&hctx->cpu_notifier); + + hctx->tags = set->tags[i]; + + /* + * Allocate space for all possible cpus to avoid allocation in + * runtime + */ + hctx->ctxs = kmalloc_node(nr_cpu_ids * sizeof(void *), + GFP_KERNEL, node); + if (!hctx->ctxs) + break; + + if (blk_mq_alloc_bitmap(&hctx->ctx_map, node)) + break; + + hctx->nr_ctx = 0; + + if (set->ops->init_hctx && + set->ops->init_hctx(hctx, set->driver_data, i)) + break; + } + + if (i == q->nr_hw_queues) + return 0; + + /* + * Init failed + */ + blk_mq_exit_hw_queues(q, set, i); + + return 1; +} + +static void blk_mq_init_cpu_queues(struct request_queue *q, + unsigned int nr_hw_queues) +{ + unsigned int i; + + for_each_possible_cpu(i) { + struct blk_mq_ctx *__ctx = per_cpu_ptr(q->queue_ctx, i); + struct blk_mq_hw_ctx *hctx; + + memset(__ctx, 0, sizeof(*__ctx)); + __ctx->cpu = i; + spin_lock_init(&__ctx->lock); + INIT_LIST_HEAD(&__ctx->rq_list); + __ctx->queue = q; + + /* If the cpu isn't online, the cpu is mapped to first hctx */ + if (!cpu_online(i)) + continue; + + hctx = q->mq_ops->map_queue(q, i); + cpumask_set_cpu(i, hctx->cpumask); + hctx->nr_ctx++; + + /* + * Set local node, IFF we have more than one hw queue. If + * not, we remain on the home node of the device + */ + if (nr_hw_queues > 1 && hctx->numa_node == NUMA_NO_NODE) + hctx->numa_node = cpu_to_node(i); + } +} + +static void blk_mq_map_swqueue(struct request_queue *q) +{ + unsigned int i; + struct blk_mq_hw_ctx *hctx; + struct blk_mq_ctx *ctx; + + queue_for_each_hw_ctx(q, hctx, i) { + cpumask_clear(hctx->cpumask); + hctx->nr_ctx = 0; + } + + /* + * Map software to hardware queues + */ + queue_for_each_ctx(q, ctx, i) { + /* If the cpu isn't online, the cpu is mapped to first hctx */ + if (!cpu_online(i)) + continue; + + hctx = q->mq_ops->map_queue(q, i); + cpumask_set_cpu(i, hctx->cpumask); + ctx->index_hw = hctx->nr_ctx; + hctx->ctxs[hctx->nr_ctx++] = ctx; + } + + queue_for_each_hw_ctx(q, hctx, i) { + /* + * If not software queues are mapped to this hardware queue, + * disable it and free the request entries + */ + if (!hctx->nr_ctx) { + struct blk_mq_tag_set *set = q->tag_set; + + if (set->tags[i]) { + blk_mq_free_rq_map(set, set->tags[i], i); + set->tags[i] = NULL; + hctx->tags = NULL; + } + continue; + } + + /* + * Initialize batch roundrobin counts + */ + hctx->next_cpu = cpumask_first(hctx->cpumask); + hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; + } +} + +static void blk_mq_update_tag_set_depth(struct blk_mq_tag_set *set) +{ + struct blk_mq_hw_ctx *hctx; + struct request_queue *q; + bool shared; + int i; + + if (set->tag_list.next == set->tag_list.prev) + shared = false; + else + shared = true; + + list_for_each_entry(q, &set->tag_list, tag_set_list) { + blk_mq_freeze_queue(q); + + queue_for_each_hw_ctx(q, hctx, i) { + if (shared) + hctx->flags |= BLK_MQ_F_TAG_SHARED; + else + hctx->flags &= ~BLK_MQ_F_TAG_SHARED; + } + blk_mq_unfreeze_queue(q); + } +} + +static void blk_mq_del_queue_tag_set(struct request_queue *q) +{ + struct blk_mq_tag_set *set = q->tag_set; + + blk_mq_freeze_queue(q); + + mutex_lock(&set->tag_list_lock); + list_del_init(&q->tag_set_list); + blk_mq_update_tag_set_depth(set); + mutex_unlock(&set->tag_list_lock); + + blk_mq_unfreeze_queue(q); +} + +static void blk_mq_add_queue_tag_set(struct blk_mq_tag_set *set, + struct request_queue *q) +{ + q->tag_set = set; + + mutex_lock(&set->tag_list_lock); + list_add_tail(&q->tag_set_list, &set->tag_list); + blk_mq_update_tag_set_depth(set); + mutex_unlock(&set->tag_list_lock); +} + +struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set) +{ + struct blk_mq_hw_ctx **hctxs; + struct blk_mq_ctx __percpu *ctx; + struct request_queue *q; + unsigned int *map; + int i; + + ctx = alloc_percpu(struct blk_mq_ctx); + if (!ctx) + return ERR_PTR(-ENOMEM); + + hctxs = kmalloc_node(set->nr_hw_queues * sizeof(*hctxs), GFP_KERNEL, + set->numa_node); + + if (!hctxs) + goto err_percpu; + + map = blk_mq_make_queue_map(set); + if (!map) + goto err_map; + + for (i = 0; i < set->nr_hw_queues; i++) { + int node = blk_mq_hw_queue_to_node(map, i); + + hctxs[i] = kzalloc_node(sizeof(struct blk_mq_hw_ctx), + GFP_KERNEL, node); + if (!hctxs[i]) + goto err_hctxs; + + if (!zalloc_cpumask_var(&hctxs[i]->cpumask, GFP_KERNEL)) + goto err_hctxs; + + atomic_set(&hctxs[i]->nr_active, 0); + hctxs[i]->numa_node = node; + hctxs[i]->queue_num = i; + } + + q = blk_alloc_queue_node(GFP_KERNEL, set->numa_node); + if (!q) + goto err_hctxs; + + if (percpu_counter_init(&q->mq_usage_counter, 0)) + goto err_map; + + setup_timer(&q->timeout, blk_mq_rq_timer, (unsigned long) q); + blk_queue_rq_timeout(q, 30000); + + q->nr_queues = nr_cpu_ids; + q->nr_hw_queues = set->nr_hw_queues; + q->mq_map = map; + + q->queue_ctx = ctx; + q->queue_hw_ctx = hctxs; + + q->mq_ops = set->ops; + q->queue_flags |= QUEUE_FLAG_MQ_DEFAULT; + + if (!(set->flags & BLK_MQ_F_SG_MERGE)) + q->queue_flags |= 1 << QUEUE_FLAG_NO_SG_MERGE; + + q->sg_reserved_size = INT_MAX; + + INIT_WORK(&q->requeue_work, blk_mq_requeue_work); + INIT_LIST_HEAD(&q->requeue_list); + spin_lock_init(&q->requeue_lock); + + if (q->nr_hw_queues > 1) + blk_queue_make_request(q, blk_mq_make_request); + else + blk_queue_make_request(q, blk_sq_make_request); + + blk_queue_rq_timed_out(q, blk_mq_rq_timed_out); + if (set->timeout) + blk_queue_rq_timeout(q, set->timeout); + + /* + * Do this after blk_queue_make_request() overrides it... + */ + q->nr_requests = set->queue_depth; + + if (set->ops->complete) + blk_queue_softirq_done(q, set->ops->complete); + + blk_mq_init_flush(q); + blk_mq_init_cpu_queues(q, set->nr_hw_queues); + + q->flush_rq = kzalloc(round_up(sizeof(struct request) + + set->cmd_size, cache_line_size()), + GFP_KERNEL); + if (!q->flush_rq) + goto err_hw; + + if (blk_mq_init_hw_queues(q, set)) + goto err_flush_rq; + + mutex_lock(&all_q_mutex); + list_add_tail(&q->all_q_node, &all_q_list); + mutex_unlock(&all_q_mutex); + + blk_mq_add_queue_tag_set(set, q); + + blk_mq_map_swqueue(q); + + return q; + +err_flush_rq: + kfree(q->flush_rq); +err_hw: + blk_cleanup_queue(q); +err_hctxs: + kfree(map); + for (i = 0; i < set->nr_hw_queues; i++) { + if (!hctxs[i]) + break; + free_cpumask_var(hctxs[i]->cpumask); + kfree(hctxs[i]); + } +err_map: + kfree(hctxs); +err_percpu: + free_percpu(ctx); + return ERR_PTR(-ENOMEM); +} +EXPORT_SYMBOL(blk_mq_init_queue); + +void blk_mq_free_queue(struct request_queue *q) +{ + struct blk_mq_tag_set *set = q->tag_set; + + blk_mq_del_queue_tag_set(q); + + blk_mq_exit_hw_queues(q, set, set->nr_hw_queues); + blk_mq_free_hw_queues(q, set); + + percpu_counter_destroy(&q->mq_usage_counter); + + free_percpu(q->queue_ctx); + kfree(q->queue_hw_ctx); + kfree(q->mq_map); + + q->queue_ctx = NULL; + q->queue_hw_ctx = NULL; + q->mq_map = NULL; + + mutex_lock(&all_q_mutex); + list_del_init(&q->all_q_node); + mutex_unlock(&all_q_mutex); +} + +/* Basically redo blk_mq_init_queue with queue frozen */ +static void blk_mq_queue_reinit(struct request_queue *q) +{ + blk_mq_freeze_queue(q); + + blk_mq_sysfs_unregister(q); + + blk_mq_update_queue_map(q->mq_map, q->nr_hw_queues); + + /* + * redo blk_mq_init_cpu_queues and blk_mq_init_hw_queues. FIXME: maybe + * we should change hctx numa_node according to new topology (this + * involves free and re-allocate memory, worthy doing?) + */ + + blk_mq_map_swqueue(q); + + blk_mq_sysfs_register(q); + + blk_mq_unfreeze_queue(q); +} + +static int blk_mq_queue_reinit_notify(struct notifier_block *nb, + unsigned long action, void *hcpu) +{ + struct request_queue *q; + + /* + * Before new mappings are established, hotadded cpu might already + * start handling requests. This doesn't break anything as we map + * offline CPUs to first hardware queue. We will re-init the queue + * below to get optimal settings. + */ + if (action != CPU_DEAD && action != CPU_DEAD_FROZEN && + action != CPU_ONLINE && action != CPU_ONLINE_FROZEN) + return NOTIFY_OK; + + mutex_lock(&all_q_mutex); + list_for_each_entry(q, &all_q_list, all_q_node) + blk_mq_queue_reinit(q); + mutex_unlock(&all_q_mutex); + return NOTIFY_OK; +} + +/* + * Alloc a tag set to be associated with one or more request queues. + * May fail with EINVAL for various error conditions. May adjust the + * requested depth down, if if it too large. In that case, the set + * value will be stored in set->queue_depth. + */ +int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set) +{ + int i; + + if (!set->nr_hw_queues) + return -EINVAL; + if (!set->queue_depth) + return -EINVAL; + if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN) + return -EINVAL; + + if (!set->nr_hw_queues || !set->ops->queue_rq || !set->ops->map_queue) + return -EINVAL; + + if (set->queue_depth > BLK_MQ_MAX_DEPTH) { + pr_info("blk-mq: reduced tag depth to %u\n", + BLK_MQ_MAX_DEPTH); + set->queue_depth = BLK_MQ_MAX_DEPTH; + } + + set->tags = kmalloc_node(set->nr_hw_queues * + sizeof(struct blk_mq_tags *), + GFP_KERNEL, set->numa_node); + if (!set->tags) + goto out; + + for (i = 0; i < set->nr_hw_queues; i++) { + set->tags[i] = blk_mq_init_rq_map(set, i); + if (!set->tags[i]) + goto out_unwind; + } + + mutex_init(&set->tag_list_lock); + INIT_LIST_HEAD(&set->tag_list); + + return 0; + +out_unwind: + while (--i >= 0) + blk_mq_free_rq_map(set, set->tags[i], i); +out: + return -ENOMEM; +} +EXPORT_SYMBOL(blk_mq_alloc_tag_set); + +void blk_mq_free_tag_set(struct blk_mq_tag_set *set) +{ + int i; + + for (i = 0; i < set->nr_hw_queues; i++) { + if (set->tags[i]) + blk_mq_free_rq_map(set, set->tags[i], i); + } + + kfree(set->tags); +} +EXPORT_SYMBOL(blk_mq_free_tag_set); + +int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr) +{ + struct blk_mq_tag_set *set = q->tag_set; + struct blk_mq_hw_ctx *hctx; + int i, ret; + + if (!set || nr > set->queue_depth) + return -EINVAL; + + ret = 0; + queue_for_each_hw_ctx(q, hctx, i) { + ret = blk_mq_tag_update_depth(hctx->tags, nr); + if (ret) + break; + } + + if (!ret) + q->nr_requests = nr; + + return ret; +} + +void blk_mq_disable_hotplug(void) +{ + mutex_lock(&all_q_mutex); +} + +void blk_mq_enable_hotplug(void) +{ + mutex_unlock(&all_q_mutex); +} + +static int __init blk_mq_init(void) +{ + blk_mq_cpu_init(); + + /* Must be called after percpu_counter_hotcpu_callback() */ + hotcpu_notifier(blk_mq_queue_reinit_notify, -10); + + return 0; +} +subsys_initcall(blk_mq_init); diff --git a/block/blk-mq.h b/block/blk-mq.h new file mode 100644 index 00000000000..26460884c6c --- /dev/null +++ b/block/blk-mq.h @@ -0,0 +1,117 @@ +#ifndef INT_BLK_MQ_H +#define INT_BLK_MQ_H + +struct blk_mq_tag_set; + +struct blk_mq_ctx { + struct { + spinlock_t lock; + struct list_head rq_list; + } ____cacheline_aligned_in_smp; + + unsigned int cpu; + unsigned int index_hw; + + unsigned int last_tag ____cacheline_aligned_in_smp; + + /* incremented at dispatch time */ + unsigned long rq_dispatched[2]; + unsigned long rq_merged; + + /* incremented at completion time */ + unsigned long ____cacheline_aligned_in_smp rq_completed[2]; + + struct request_queue *queue; + struct kobject kobj; +} ____cacheline_aligned_in_smp; + +void __blk_mq_complete_request(struct request *rq); +void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async); +void blk_mq_init_flush(struct request_queue *q); +void blk_mq_drain_queue(struct request_queue *q); +void blk_mq_free_queue(struct request_queue *q); +void blk_mq_clone_flush_request(struct request *flush_rq, + struct request *orig_rq); +int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr); + +/* + * CPU hotplug helpers + */ +struct blk_mq_cpu_notifier; +void blk_mq_init_cpu_notifier(struct blk_mq_cpu_notifier *notifier, + int (*fn)(void *, unsigned long, unsigned int), + void *data); +void blk_mq_register_cpu_notifier(struct blk_mq_cpu_notifier *notifier); +void blk_mq_unregister_cpu_notifier(struct blk_mq_cpu_notifier *notifier); +void blk_mq_cpu_init(void); +void blk_mq_enable_hotplug(void); +void blk_mq_disable_hotplug(void); + +/* + * CPU -> queue mappings + */ +extern unsigned int *blk_mq_make_queue_map(struct blk_mq_tag_set *set); +extern int blk_mq_update_queue_map(unsigned int *map, unsigned int nr_queues); +extern int blk_mq_hw_queue_to_node(unsigned int *map, unsigned int); + +/* + * sysfs helpers + */ +extern int blk_mq_sysfs_register(struct request_queue *q); +extern void blk_mq_sysfs_unregister(struct request_queue *q); + +/* + * Basic implementation of sparser bitmap, allowing the user to spread + * the bits over more cachelines. + */ +struct blk_align_bitmap { + unsigned long word; + unsigned long depth; +} ____cacheline_aligned_in_smp; + +static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q, + unsigned int cpu) +{ + return per_cpu_ptr(q->queue_ctx, cpu); +} + +/* + * This assumes per-cpu software queueing queues. They could be per-node + * as well, for instance. For now this is hardcoded as-is. Note that we don't + * care about preemption, since we know the ctx's are persistent. This does + * mean that we can't rely on ctx always matching the currently running CPU. + */ +static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q) +{ + return __blk_mq_get_ctx(q, get_cpu()); +} + +static inline void blk_mq_put_ctx(struct blk_mq_ctx *ctx) +{ + put_cpu(); +} + +struct blk_mq_alloc_data { + /* input parameter */ + struct request_queue *q; + gfp_t gfp; + bool reserved; + + /* input & output parameter */ + struct blk_mq_ctx *ctx; + struct blk_mq_hw_ctx *hctx; +}; + +static inline void blk_mq_set_alloc_data(struct blk_mq_alloc_data *data, + struct request_queue *q, gfp_t gfp, bool reserved, + struct blk_mq_ctx *ctx, + struct blk_mq_hw_ctx *hctx) +{ + data->q = q; + data->gfp = gfp; + data->reserved = reserved; + data->ctx = ctx; + data->hctx = hctx; +} + +#endif diff --git a/block/blk-settings.c b/block/blk-settings.c index c50ecf0ea3b..f1a1795a568 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -113,6 +113,7 @@ void blk_set_default_limits(struct queue_limits *lim) lim->seg_boundary_mask = BLK_SEG_BOUNDARY_MASK; lim->max_segment_size = BLK_MAX_SEGMENT_SIZE; lim->max_sectors = lim->max_hw_sectors = BLK_SAFE_MAX_SECTORS; + lim->chunk_sectors = 0; lim->max_write_same_sectors = 0; lim->max_discard_sectors = 0; lim->discard_granularity = 0; @@ -144,6 +145,7 @@ void blk_set_stacking_limits(struct queue_limits *lim) lim->discard_zeroes_data = 1; lim->max_segments = USHRT_MAX; lim->max_hw_sectors = UINT_MAX; + lim->max_segment_size = UINT_MAX; lim->max_sectors = UINT_MAX; lim->max_write_same_sectors = UINT_MAX; } @@ -195,17 +197,17 @@ EXPORT_SYMBOL(blk_queue_make_request); /** * blk_queue_bounce_limit - set bounce buffer limit for queue * @q: the request queue for the device - * @dma_mask: the maximum address the device can handle + * @max_addr: the maximum address the device can handle * * Description: * Different hardware can have different requirements as to what pages * it can do I/O directly to. A low level driver can call * blk_queue_bounce_limit to have lower memory pages allocated as bounce - * buffers for doing I/O to pages residing above @dma_mask. + * buffers for doing I/O to pages residing above @max_addr. **/ -void blk_queue_bounce_limit(struct request_queue *q, u64 dma_mask) +void blk_queue_bounce_limit(struct request_queue *q, u64 max_addr) { - unsigned long b_pfn = dma_mask >> PAGE_SHIFT; + unsigned long b_pfn = max_addr >> PAGE_SHIFT; int dma = 0; q->bounce_gfp = GFP_NOIO; @@ -276,6 +278,26 @@ void blk_queue_max_hw_sectors(struct request_queue *q, unsigned int max_hw_secto EXPORT_SYMBOL(blk_queue_max_hw_sectors); /** + * blk_queue_chunk_sectors - set size of the chunk for this queue + * @q: the request queue for the device + * @chunk_sectors: chunk sectors in the usual 512b unit + * + * Description: + * If a driver doesn't want IOs to cross a given chunk size, it can set + * this limit and prevent merging across chunks. Note that the chunk size + * must currently be a power-of-2 in sectors. Also note that the block + * layer must accept a page worth of data at any offset. So if the + * crossing of chunks is a hard limitation in the driver, it must still be + * prepared to split single page bios. + **/ +void blk_queue_chunk_sectors(struct request_queue *q, unsigned int chunk_sectors) +{ + BUG_ON(!is_power_of_2(chunk_sectors)); + q->limits.chunk_sectors = chunk_sectors; +} +EXPORT_SYMBOL(blk_queue_chunk_sectors); + +/** * blk_queue_max_discard_sectors - set max sectors for a single discard * @q: the request queue for the device * @max_discard_sectors: maximum number of sectors to discard @@ -591,6 +613,10 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, ret = -1; } + t->raid_partial_stripes_expensive = + max(t->raid_partial_stripes_expensive, + b->raid_partial_stripes_expensive); + /* Find lowest common alignment_offset */ t->alignment_offset = lcm(t->alignment_offset, alignment) & (max(t->physical_block_size, t->io_min) - 1); diff --git a/block/blk-softirq.c b/block/blk-softirq.c index ec9e60636f4..53b1737e978 100644 --- a/block/blk-softirq.c +++ b/block/blk-softirq.c @@ -23,20 +23,20 @@ static void blk_done_softirq(struct softirq_action *h) struct list_head *cpu_list, local_list; local_irq_disable(); - cpu_list = &__get_cpu_var(blk_cpu_done); + cpu_list = this_cpu_ptr(&blk_cpu_done); list_replace_init(cpu_list, &local_list); local_irq_enable(); while (!list_empty(&local_list)) { struct request *rq; - rq = list_entry(local_list.next, struct request, csd.list); - list_del_init(&rq->csd.list); + rq = list_entry(local_list.next, struct request, ipi_list); + list_del_init(&rq->ipi_list); rq->q->softirq_done_fn(rq); } } -#if defined(CONFIG_SMP) && defined(CONFIG_USE_GENERIC_SMP_HELPERS) +#ifdef CONFIG_SMP static void trigger_softirq(void *data) { struct request *rq = data; @@ -44,10 +44,10 @@ static void trigger_softirq(void *data) struct list_head *list; local_irq_save(flags); - list = &__get_cpu_var(blk_cpu_done); - list_add_tail(&rq->csd.list, list); + list = this_cpu_ptr(&blk_cpu_done); + list_add_tail(&rq->ipi_list, list); - if (list->next == &rq->csd.list) + if (list->next == &rq->ipi_list) raise_softirq_irqoff(BLOCK_SOFTIRQ); local_irq_restore(flags); @@ -65,13 +65,13 @@ static int raise_blk_irq(int cpu, struct request *rq) data->info = rq; data->flags = 0; - __smp_call_function_single(cpu, data, 0); + smp_call_function_single_async(cpu, data); return 0; } return 1; } -#else /* CONFIG_SMP && CONFIG_USE_GENERIC_SMP_HELPERS */ +#else /* CONFIG_SMP */ static int raise_blk_irq(int cpu, struct request *rq) { return 1; @@ -90,7 +90,7 @@ static int blk_cpu_notify(struct notifier_block *self, unsigned long action, local_irq_disable(); list_splice_init(&per_cpu(blk_cpu_done, cpu), - &__get_cpu_var(blk_cpu_done)); + this_cpu_ptr(&blk_cpu_done)); raise_softirq_irqoff(BLOCK_SOFTIRQ); local_irq_enable(); } @@ -135,8 +135,8 @@ void __blk_complete_request(struct request *req) if (ccpu == cpu || shared) { struct list_head *list; do_local: - list = &__get_cpu_var(blk_cpu_done); - list_add_tail(&req->csd.list, list); + list = this_cpu_ptr(&blk_cpu_done); + list_add_tail(&req->ipi_list, list); /* * if the list only contains our just added request, @@ -144,7 +144,7 @@ do_local: * entries there, someone already raised the irq but it * hasn't run yet. */ - if (list->next == &req->csd.list) + if (list->next == &req->ipi_list) raise_softirq_irqoff(BLOCK_SOFTIRQ); } else if (raise_blk_irq(ccpu, req)) goto do_local; diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 3aa5b195f4d..23321fbab29 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -7,9 +7,11 @@ #include <linux/bio.h> #include <linux/blkdev.h> #include <linux/blktrace_api.h> +#include <linux/blk-mq.h> #include "blk.h" #include "blk-cgroup.h" +#include "blk-mq.h" struct queue_sysfs_entry { struct attribute attr; @@ -46,11 +48,10 @@ static ssize_t queue_requests_show(struct request_queue *q, char *page) static ssize_t queue_requests_store(struct request_queue *q, const char *page, size_t count) { - struct request_list *rl; unsigned long nr; - int ret; + int ret, err; - if (!q->request_fn) + if (!q->request_fn && !q->mq_ops) return -EINVAL; ret = queue_var_store(&nr, page, count); @@ -60,40 +61,14 @@ queue_requests_store(struct request_queue *q, const char *page, size_t count) if (nr < BLKDEV_MIN_RQ) nr = BLKDEV_MIN_RQ; - spin_lock_irq(q->queue_lock); - q->nr_requests = nr; - blk_queue_congestion_threshold(q); - - /* congestion isn't cgroup aware and follows root blkcg for now */ - rl = &q->root_rl; - - if (rl->count[BLK_RW_SYNC] >= queue_congestion_on_threshold(q)) - blk_set_queue_congested(q, BLK_RW_SYNC); - else if (rl->count[BLK_RW_SYNC] < queue_congestion_off_threshold(q)) - blk_clear_queue_congested(q, BLK_RW_SYNC); - - if (rl->count[BLK_RW_ASYNC] >= queue_congestion_on_threshold(q)) - blk_set_queue_congested(q, BLK_RW_ASYNC); - else if (rl->count[BLK_RW_ASYNC] < queue_congestion_off_threshold(q)) - blk_clear_queue_congested(q, BLK_RW_ASYNC); - - blk_queue_for_each_rl(rl, q) { - if (rl->count[BLK_RW_SYNC] >= q->nr_requests) { - blk_set_rl_full(rl, BLK_RW_SYNC); - } else { - blk_clear_rl_full(rl, BLK_RW_SYNC); - wake_up(&rl->wait[BLK_RW_SYNC]); - } - - if (rl->count[BLK_RW_ASYNC] >= q->nr_requests) { - blk_set_rl_full(rl, BLK_RW_ASYNC); - } else { - blk_clear_rl_full(rl, BLK_RW_ASYNC); - wake_up(&rl->wait[BLK_RW_ASYNC]); - } - } + if (q->request_fn) + err = blk_update_nr_requests(q, nr); + else + err = blk_mq_update_nr_requests(q, nr); + + if (err) + return err; - spin_unlock_irq(q->queue_lock); return ret; } @@ -287,7 +262,7 @@ static ssize_t queue_rq_affinity_store(struct request_queue *q, const char *page, size_t count) { ssize_t ret = -EINVAL; -#if defined(CONFIG_USE_GENERIC_SMP_HELPERS) +#ifdef CONFIG_SMP unsigned long val; ret = queue_var_store(&val, page, count); @@ -542,6 +517,11 @@ static void blk_release_queue(struct kobject *kobj) if (q->queue_tags) __blk_queue_free_tags(q); + if (q->mq_ops) + blk_mq_free_queue(q); + + kfree(q->flush_rq); + blk_trace_shutdown(q); bdi_destroy(&q->backing_dev_info); @@ -575,6 +555,7 @@ int blk_register_queue(struct gendisk *disk) * bypass from queue allocation. */ blk_queue_bypass_end(q); + queue_flag_set_unlocked(QUEUE_FLAG_INIT_DONE, q); ret = blk_trace_init_sysfs(dev); if (ret) @@ -588,6 +569,9 @@ int blk_register_queue(struct gendisk *disk) kobject_uevent(&q->kobj, KOBJ_ADD); + if (q->mq_ops) + blk_mq_register_disk(disk); + if (!q->request_fn) return 0; @@ -610,6 +594,9 @@ void blk_unregister_queue(struct gendisk *disk) if (WARN_ON(!q)) return; + if (q->mq_ops) + blk_mq_unregister_disk(disk); + if (q->request_fn) elv_unregister_queue(q); diff --git a/block/blk-tag.c b/block/blk-tag.c index 3f33d867226..a185b86741e 100644 --- a/block/blk-tag.c +++ b/block/blk-tag.c @@ -27,18 +27,15 @@ struct request *blk_queue_find_tag(struct request_queue *q, int tag) EXPORT_SYMBOL(blk_queue_find_tag); /** - * __blk_free_tags - release a given set of tag maintenance info + * blk_free_tags - release a given set of tag maintenance info * @bqt: the tag map to free * - * Tries to free the specified @bqt. Returns true if it was - * actually freed and false if there are still references using it + * Drop the reference count on @bqt and frees it when the last reference + * is dropped. */ -static int __blk_free_tags(struct blk_queue_tag *bqt) +void blk_free_tags(struct blk_queue_tag *bqt) { - int retval; - - retval = atomic_dec_and_test(&bqt->refcnt); - if (retval) { + if (atomic_dec_and_test(&bqt->refcnt)) { BUG_ON(find_first_bit(bqt->tag_map, bqt->max_depth) < bqt->max_depth); @@ -50,9 +47,8 @@ static int __blk_free_tags(struct blk_queue_tag *bqt) kfree(bqt); } - - return retval; } +EXPORT_SYMBOL(blk_free_tags); /** * __blk_queue_free_tags - release tag maintenance info @@ -69,28 +65,13 @@ void __blk_queue_free_tags(struct request_queue *q) if (!bqt) return; - __blk_free_tags(bqt); + blk_free_tags(bqt); q->queue_tags = NULL; queue_flag_clear_unlocked(QUEUE_FLAG_QUEUED, q); } /** - * blk_free_tags - release a given set of tag maintenance info - * @bqt: the tag map to free - * - * For externally managed @bqt frees the map. Callers of this - * function must guarantee to have released all the queues that - * might have been using this tag map. - */ -void blk_free_tags(struct blk_queue_tag *bqt) -{ - if (unlikely(!__blk_free_tags(bqt))) - BUG(); -} -EXPORT_SYMBOL(blk_free_tags); - -/** * blk_queue_free_tags - release tag maintenance info * @q: the request queue for the device * diff --git a/block/blk-throttle.c b/block/blk-throttle.c index 8331aba9426..3fdb21a390c 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -256,6 +256,12 @@ static struct throtl_data *sq_to_td(struct throtl_service_queue *sq) } \ } while (0) +static void tg_stats_init(struct tg_stats_cpu *tg_stats) +{ + blkg_rwstat_init(&tg_stats->service_bytes); + blkg_rwstat_init(&tg_stats->serviced); +} + /* * Worker for allocating per cpu stat for tgs. This is scheduled on the * system_wq once there are some groups on the alloc_list waiting for @@ -269,12 +275,16 @@ static void tg_stats_alloc_fn(struct work_struct *work) alloc_stats: if (!stats_cpu) { + int cpu; + stats_cpu = alloc_percpu(struct tg_stats_cpu); if (!stats_cpu) { /* allocation failed, try again after some time */ schedule_delayed_work(dwork, msecs_to_jiffies(10)); return; } + for_each_possible_cpu(cpu) + tg_stats_init(per_cpu_ptr(stats_cpu, cpu)); } spin_lock_irq(&tg_stats_alloc_lock); @@ -734,7 +744,7 @@ static inline void throtl_extend_slice(struct throtl_grp *tg, bool rw, static bool throtl_slice_used(struct throtl_grp *tg, bool rw) { if (time_in_range(jiffies, tg->slice_start[rw], tg->slice_end[rw])) - return 0; + return false; return 1; } @@ -832,7 +842,7 @@ static bool tg_with_in_iops_limit(struct throtl_grp *tg, struct bio *bio, if (tg->io_disp[rw] + 1 <= io_allowed) { if (wait) *wait = 0; - return 1; + return true; } /* Calc approx time to dispatch */ @@ -867,14 +877,14 @@ static bool tg_with_in_bps_limit(struct throtl_grp *tg, struct bio *bio, do_div(tmp, HZ); bytes_allowed = tmp; - if (tg->bytes_disp[rw] + bio->bi_size <= bytes_allowed) { + if (tg->bytes_disp[rw] + bio->bi_iter.bi_size <= bytes_allowed) { if (wait) *wait = 0; - return 1; + return true; } /* Calc approx time to dispatch */ - extra_bytes = tg->bytes_disp[rw] + bio->bi_size - bytes_allowed; + extra_bytes = tg->bytes_disp[rw] + bio->bi_iter.bi_size - bytes_allowed; jiffy_wait = div64_u64(extra_bytes * HZ, tg->bps[rw]); if (!jiffy_wait) @@ -913,7 +923,7 @@ static bool tg_may_dispatch(struct throtl_grp *tg, struct bio *bio, if (tg->bps[rw] == -1 && tg->iops[rw] == -1) { if (wait) *wait = 0; - return 1; + return true; } /* @@ -977,7 +987,7 @@ static void throtl_charge_bio(struct throtl_grp *tg, struct bio *bio) bool rw = bio_data_dir(bio); /* Charge the bio to the group */ - tg->bytes_disp[rw] += bio->bi_size; + tg->bytes_disp[rw] += bio->bi_iter.bi_size; tg->io_disp[rw]++; /* @@ -993,8 +1003,8 @@ static void throtl_charge_bio(struct throtl_grp *tg, struct bio *bio) */ if (!(bio->bi_rw & REQ_THROTTLED)) { bio->bi_rw |= REQ_THROTTLED; - throtl_update_dispatch_stats(tg_to_blkg(tg), bio->bi_size, - bio->bi_rw); + throtl_update_dispatch_stats(tg_to_blkg(tg), + bio->bi_iter.bi_size, bio->bi_rw); } } @@ -1248,7 +1258,7 @@ out_unlock: * of throtl_data->service_queue. Those bio's are ready and issued by this * function. */ -void blk_throtl_dispatch_work_fn(struct work_struct *work) +static void blk_throtl_dispatch_work_fn(struct work_struct *work) { struct throtl_data *td = container_of(work, struct throtl_data, dispatch_work); @@ -1293,13 +1303,10 @@ static u64 tg_prfill_cpu_rwstat(struct seq_file *sf, return __blkg_prfill_rwstat(sf, pd, &rwstat); } -static int tg_print_cpu_rwstat(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *sf) +static int tg_print_cpu_rwstat(struct seq_file *sf, void *v) { - struct blkcg *blkcg = css_to_blkcg(css); - - blkcg_print_blkgs(sf, blkcg, tg_prfill_cpu_rwstat, &blkcg_policy_throtl, - cft->private, true); + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), tg_prfill_cpu_rwstat, + &blkcg_policy_throtl, seq_cft(sf)->private, true); return 0; } @@ -1325,26 +1332,24 @@ static u64 tg_prfill_conf_uint(struct seq_file *sf, struct blkg_policy_data *pd, return __blkg_prfill_u64(sf, pd, v); } -static int tg_print_conf_u64(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *sf) +static int tg_print_conf_u64(struct seq_file *sf, void *v) { - blkcg_print_blkgs(sf, css_to_blkcg(css), tg_prfill_conf_u64, - &blkcg_policy_throtl, cft->private, false); + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), tg_prfill_conf_u64, + &blkcg_policy_throtl, seq_cft(sf)->private, false); return 0; } -static int tg_print_conf_uint(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *sf) +static int tg_print_conf_uint(struct seq_file *sf, void *v) { - blkcg_print_blkgs(sf, css_to_blkcg(css), tg_prfill_conf_uint, - &blkcg_policy_throtl, cft->private, false); + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), tg_prfill_conf_uint, + &blkcg_policy_throtl, seq_cft(sf)->private, false); return 0; } -static int tg_set_conf(struct cgroup_subsys_state *css, struct cftype *cft, - const char *buf, bool is_u64) +static ssize_t tg_set_conf(struct kernfs_open_file *of, + char *buf, size_t nbytes, loff_t off, bool is_u64) { - struct blkcg *blkcg = css_to_blkcg(css); + struct blkcg *blkcg = css_to_blkcg(of_css(of)); struct blkg_conf_ctx ctx; struct throtl_grp *tg; struct throtl_service_queue *sq; @@ -1363,9 +1368,9 @@ static int tg_set_conf(struct cgroup_subsys_state *css, struct cftype *cft, ctx.v = -1; if (is_u64) - *(u64 *)((void *)tg + cft->private) = ctx.v; + *(u64 *)((void *)tg + of_cft(of)->private) = ctx.v; else - *(unsigned int *)((void *)tg + cft->private) = ctx.v; + *(unsigned int *)((void *)tg + of_cft(of)->private) = ctx.v; throtl_log(&tg->service_queue, "limit change rbps=%llu wbps=%llu riops=%u wiops=%u", @@ -1399,59 +1404,55 @@ static int tg_set_conf(struct cgroup_subsys_state *css, struct cftype *cft, } blkg_conf_finish(&ctx); - return 0; + return nbytes; } -static int tg_set_conf_u64(struct cgroup_subsys_state *css, struct cftype *cft, - const char *buf) +static ssize_t tg_set_conf_u64(struct kernfs_open_file *of, + char *buf, size_t nbytes, loff_t off) { - return tg_set_conf(css, cft, buf, true); + return tg_set_conf(of, buf, nbytes, off, true); } -static int tg_set_conf_uint(struct cgroup_subsys_state *css, struct cftype *cft, - const char *buf) +static ssize_t tg_set_conf_uint(struct kernfs_open_file *of, + char *buf, size_t nbytes, loff_t off) { - return tg_set_conf(css, cft, buf, false); + return tg_set_conf(of, buf, nbytes, off, false); } static struct cftype throtl_files[] = { { .name = "throttle.read_bps_device", .private = offsetof(struct throtl_grp, bps[READ]), - .read_seq_string = tg_print_conf_u64, - .write_string = tg_set_conf_u64, - .max_write_len = 256, + .seq_show = tg_print_conf_u64, + .write = tg_set_conf_u64, }, { .name = "throttle.write_bps_device", .private = offsetof(struct throtl_grp, bps[WRITE]), - .read_seq_string = tg_print_conf_u64, - .write_string = tg_set_conf_u64, - .max_write_len = 256, + .seq_show = tg_print_conf_u64, + .write = tg_set_conf_u64, }, { .name = "throttle.read_iops_device", .private = offsetof(struct throtl_grp, iops[READ]), - .read_seq_string = tg_print_conf_uint, - .write_string = tg_set_conf_uint, - .max_write_len = 256, + .seq_show = tg_print_conf_uint, + .write = tg_set_conf_uint, }, { .name = "throttle.write_iops_device", .private = offsetof(struct throtl_grp, iops[WRITE]), - .read_seq_string = tg_print_conf_uint, - .write_string = tg_set_conf_uint, - .max_write_len = 256, + .seq_show = tg_print_conf_uint, + .write = tg_set_conf_uint, }, { .name = "throttle.io_service_bytes", .private = offsetof(struct tg_stats_cpu, service_bytes), - .read_seq_string = tg_print_cpu_rwstat, + .seq_show = tg_print_cpu_rwstat, }, { .name = "throttle.io_serviced", .private = offsetof(struct tg_stats_cpu, serviced), - .read_seq_string = tg_print_cpu_rwstat, + .seq_show = tg_print_cpu_rwstat, }, { } /* terminate */ }; @@ -1498,7 +1499,7 @@ bool blk_throtl_bio(struct request_queue *q, struct bio *bio) if (tg) { if (!tg->has_rules[rw]) { throtl_update_dispatch_stats(tg_to_blkg(tg), - bio->bi_size, bio->bi_rw); + bio->bi_iter.bi_size, bio->bi_rw); goto out_unlock_rcu; } } @@ -1554,7 +1555,7 @@ bool blk_throtl_bio(struct request_queue *q, struct bio *bio) /* out-of-limit, queue to @tg */ throtl_log(sq, "[%c] bio. bdisp=%llu sz=%u bps=%llu iodisp=%u iops=%u queued=%d/%d", rw == READ ? 'R' : 'W', - tg->bytes_disp[rw], bio->bi_size, tg->bps[rw], + tg->bytes_disp[rw], bio->bi_iter.bi_size, tg->bps[rw], tg->io_disp[rw], tg->iops[rw], sq->nr_queued[READ], sq->nr_queued[WRITE]); diff --git a/block/blk-timeout.c b/block/blk-timeout.c index 65f10356396..95a09590ccf 100644 --- a/block/blk-timeout.c +++ b/block/blk-timeout.c @@ -7,6 +7,7 @@ #include <linux/fault-inject.h> #include "blk.h" +#include "blk-mq.h" #ifdef CONFIG_FAIL_IO_TIMEOUT @@ -31,7 +32,7 @@ static int __init fail_io_timeout_debugfs(void) struct dentry *dir = fault_create_debugfs_attr("fail_io_timeout", NULL, &fail_io_timeout); - return IS_ERR(dir) ? PTR_ERR(dir) : 0; + return PTR_ERR_OR_ZERO(dir); } late_initcall(fail_io_timeout_debugfs); @@ -88,11 +89,15 @@ static void blk_rq_timed_out(struct request *req) ret = q->rq_timed_out_fn(req); switch (ret) { case BLK_EH_HANDLED: - __blk_complete_request(req); + /* Can we use req->errors here? */ + if (q->mq_ops) + __blk_mq_complete_request(req); + else + __blk_complete_request(req); break; case BLK_EH_RESET_TIMER: - blk_clear_rq_complete(req); blk_add_timer(req); + blk_clear_rq_complete(req); break; case BLK_EH_NOT_HANDLED: /* @@ -108,6 +113,23 @@ static void blk_rq_timed_out(struct request *req) } } +void blk_rq_check_expired(struct request *rq, unsigned long *next_timeout, + unsigned int *next_set) +{ + if (time_after_eq(jiffies, rq->deadline)) { + list_del_init(&rq->timeout_list); + + /* + * Check if we raced with end io completion + */ + if (!blk_mark_rq_complete(rq)) + blk_rq_timed_out(rq); + } else if (!*next_set || time_after(*next_timeout, rq->deadline)) { + *next_timeout = rq->deadline; + *next_set = 1; + } +} + void blk_rq_timed_out_timer(unsigned long data) { struct request_queue *q = (struct request_queue *) data; @@ -117,21 +139,8 @@ void blk_rq_timed_out_timer(unsigned long data) spin_lock_irqsave(q->queue_lock, flags); - list_for_each_entry_safe(rq, tmp, &q->timeout_list, timeout_list) { - if (time_after_eq(jiffies, rq->deadline)) { - list_del_init(&rq->timeout_list); - - /* - * Check if we raced with end io completion - */ - if (blk_mark_rq_complete(rq)) - continue; - blk_rq_timed_out(rq); - } else if (!next_set || time_after(next, rq->deadline)) { - next = rq->deadline; - next_set = 1; - } - } + list_for_each_entry_safe(rq, tmp, &q->timeout_list, timeout_list) + blk_rq_check_expired(rq, &next, &next_set); if (next_set) mod_timer(&q->timeout, round_jiffies_up(next)); @@ -157,6 +166,17 @@ void blk_abort_request(struct request *req) } EXPORT_SYMBOL_GPL(blk_abort_request); +unsigned long blk_rq_timeout(unsigned long timeout) +{ + unsigned long maxt; + + maxt = round_jiffies_up(jiffies + BLK_MAX_TIMEOUT); + if (time_after(timeout, maxt)) + timeout = maxt; + + return timeout; +} + /** * blk_add_timer - Start timeout timer for a single request * @req: request that is about to start running. @@ -174,7 +194,6 @@ void blk_add_timer(struct request *req) return; BUG_ON(!list_empty(&req->timeout_list)); - BUG_ON(test_bit(REQ_ATOM_COMPLETE, &req->atomic_flags)); /* * Some LLDs, like scsi, peek at the timeout to prevent a @@ -184,17 +203,29 @@ void blk_add_timer(struct request *req) req->timeout = q->rq_timeout; req->deadline = jiffies + req->timeout; - list_add_tail(&req->timeout_list, &q->timeout_list); + if (!q->mq_ops) + list_add_tail(&req->timeout_list, &req->q->timeout_list); /* * If the timer isn't already pending or this timeout is earlier * than an existing one, modify the timer. Round up to next nearest * second. */ - expiry = round_jiffies_up(req->deadline); + expiry = blk_rq_timeout(round_jiffies_up(req->deadline)); if (!timer_pending(&q->timeout) || - time_before(expiry, q->timeout.expires)) - mod_timer(&q->timeout, expiry); -} + time_before(expiry, q->timeout.expires)) { + unsigned long diff = q->timeout.expires - expiry; + + /* + * Due to added timer slack to group timers, the timer + * will often be a little in front of what we asked for. + * So apply some tolerance here too, otherwise we keep + * modifying the timer because expires for value X + * will be X + something. + */ + if (!timer_pending(&q->timeout) || (diff >= HZ / 2)) + mod_timer(&q->timeout, expiry); + } +} diff --git a/block/blk.h b/block/blk.h index e837b8f619b..6748c4f8d7a 100644 --- a/block/blk.h +++ b/block/blk.h @@ -9,7 +9,11 @@ /* Number of requests a "batching" process may submit */ #define BLK_BATCH_REQ 32 +/* Max future timer expiry for timeouts */ +#define BLK_MAX_TIMEOUT (5 * HZ) + extern struct kmem_cache *blk_requestq_cachep; +extern struct kmem_cache *request_cachep; extern struct kobj_type blk_queue_ktype; extern struct ida blk_queue_ida; @@ -34,14 +38,30 @@ bool __blk_end_bidi_request(struct request *rq, int error, unsigned int nr_bytes, unsigned int bidi_bytes); void blk_rq_timed_out_timer(unsigned long data); +void blk_rq_check_expired(struct request *rq, unsigned long *next_timeout, + unsigned int *next_set); +unsigned long blk_rq_timeout(unsigned long timeout); +void blk_add_timer(struct request *req); void blk_delete_timer(struct request *); -void blk_add_timer(struct request *); + + +bool bio_attempt_front_merge(struct request_queue *q, struct request *req, + struct bio *bio); +bool bio_attempt_back_merge(struct request_queue *q, struct request *req, + struct bio *bio); +bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio, + unsigned int *request_count); + +void blk_account_io_start(struct request *req, bool new_io); +void blk_account_io_completion(struct request *req, unsigned int bytes); +void blk_account_io_done(struct request *req); /* * Internal atomic flags for request handling */ enum rq_atomic_flags { REQ_ATOM_COMPLETE = 0, + REQ_ATOM_STARTED, }; /* @@ -61,10 +81,9 @@ static inline void blk_clear_rq_complete(struct request *rq) /* * Internal elevator interface */ -#define ELV_ON_HASH(rq) hash_hashed(&(rq)->hash) +#define ELV_ON_HASH(rq) ((rq)->cmd_flags & REQ_HASHED) void blk_insert_flush(struct request *rq); -void blk_abort_flushes(struct request_queue *q); static inline struct request *__elv_next_request(struct request_queue *q) { @@ -96,7 +115,7 @@ static inline struct request *__elv_next_request(struct request_queue *q) q->flush_queue_delayed = 1; return NULL; } - if (unlikely(blk_queue_dying(q)) || + if (unlikely(blk_queue_bypass(q)) || !q->elevator->type->ops.elevator_dispatch_fn(q, 0)) return NULL; } @@ -168,6 +187,8 @@ static inline int queue_congestion_off_threshold(struct request_queue *q) return q->nr_congestion_off; } +extern int blk_update_nr_requests(struct request_queue *, unsigned int); + /* * Contribute to IO statistics IFF: * diff --git a/block/bounce.c b/block/bounce.c new file mode 100644 index 00000000000..ab21ba203d5 --- /dev/null +++ b/block/bounce.c @@ -0,0 +1,290 @@ +/* bounce buffer handling for block devices + * + * - Split from highmem.c + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/mm.h> +#include <linux/export.h> +#include <linux/swap.h> +#include <linux/gfp.h> +#include <linux/bio.h> +#include <linux/pagemap.h> +#include <linux/mempool.h> +#include <linux/blkdev.h> +#include <linux/init.h> +#include <linux/hash.h> +#include <linux/highmem.h> +#include <linux/bootmem.h> +#include <linux/printk.h> +#include <asm/tlbflush.h> + +#include <trace/events/block.h> + +#define POOL_SIZE 64 +#define ISA_POOL_SIZE 16 + +static mempool_t *page_pool, *isa_page_pool; + +#if defined(CONFIG_HIGHMEM) || defined(CONFIG_NEED_BOUNCE_POOL) +static __init int init_emergency_pool(void) +{ +#if defined(CONFIG_HIGHMEM) && !defined(CONFIG_MEMORY_HOTPLUG) + if (max_pfn <= max_low_pfn) + return 0; +#endif + + page_pool = mempool_create_page_pool(POOL_SIZE, 0); + BUG_ON(!page_pool); + pr_info("pool size: %d pages\n", POOL_SIZE); + + return 0; +} + +__initcall(init_emergency_pool); +#endif + +#ifdef CONFIG_HIGHMEM +/* + * highmem version, map in to vec + */ +static void bounce_copy_vec(struct bio_vec *to, unsigned char *vfrom) +{ + unsigned long flags; + unsigned char *vto; + + local_irq_save(flags); + vto = kmap_atomic(to->bv_page); + memcpy(vto + to->bv_offset, vfrom, to->bv_len); + kunmap_atomic(vto); + local_irq_restore(flags); +} + +#else /* CONFIG_HIGHMEM */ + +#define bounce_copy_vec(to, vfrom) \ + memcpy(page_address((to)->bv_page) + (to)->bv_offset, vfrom, (to)->bv_len) + +#endif /* CONFIG_HIGHMEM */ + +/* + * allocate pages in the DMA region for the ISA pool + */ +static void *mempool_alloc_pages_isa(gfp_t gfp_mask, void *data) +{ + return mempool_alloc_pages(gfp_mask | GFP_DMA, data); +} + +/* + * gets called "every" time someone init's a queue with BLK_BOUNCE_ISA + * as the max address, so check if the pool has already been created. + */ +int init_emergency_isa_pool(void) +{ + if (isa_page_pool) + return 0; + + isa_page_pool = mempool_create(ISA_POOL_SIZE, mempool_alloc_pages_isa, + mempool_free_pages, (void *) 0); + BUG_ON(!isa_page_pool); + + pr_info("isa pool size: %d pages\n", ISA_POOL_SIZE); + return 0; +} + +/* + * Simple bounce buffer support for highmem pages. Depending on the + * queue gfp mask set, *to may or may not be a highmem page. kmap it + * always, it will do the Right Thing + */ +static void copy_to_high_bio_irq(struct bio *to, struct bio *from) +{ + unsigned char *vfrom; + struct bio_vec tovec, *fromvec = from->bi_io_vec; + struct bvec_iter iter; + + bio_for_each_segment(tovec, to, iter) { + if (tovec.bv_page != fromvec->bv_page) { + /* + * fromvec->bv_offset and fromvec->bv_len might have + * been modified by the block layer, so use the original + * copy, bounce_copy_vec already uses tovec->bv_len + */ + vfrom = page_address(fromvec->bv_page) + + tovec.bv_offset; + + bounce_copy_vec(&tovec, vfrom); + flush_dcache_page(tovec.bv_page); + } + + fromvec++; + } +} + +static void bounce_end_io(struct bio *bio, mempool_t *pool, int err) +{ + struct bio *bio_orig = bio->bi_private; + struct bio_vec *bvec, *org_vec; + int i; + + if (test_bit(BIO_EOPNOTSUPP, &bio->bi_flags)) + set_bit(BIO_EOPNOTSUPP, &bio_orig->bi_flags); + + /* + * free up bounce indirect pages used + */ + bio_for_each_segment_all(bvec, bio, i) { + org_vec = bio_orig->bi_io_vec + i; + if (bvec->bv_page == org_vec->bv_page) + continue; + + dec_zone_page_state(bvec->bv_page, NR_BOUNCE); + mempool_free(bvec->bv_page, pool); + } + + bio_endio(bio_orig, err); + bio_put(bio); +} + +static void bounce_end_io_write(struct bio *bio, int err) +{ + bounce_end_io(bio, page_pool, err); +} + +static void bounce_end_io_write_isa(struct bio *bio, int err) +{ + + bounce_end_io(bio, isa_page_pool, err); +} + +static void __bounce_end_io_read(struct bio *bio, mempool_t *pool, int err) +{ + struct bio *bio_orig = bio->bi_private; + + if (test_bit(BIO_UPTODATE, &bio->bi_flags)) + copy_to_high_bio_irq(bio_orig, bio); + + bounce_end_io(bio, pool, err); +} + +static void bounce_end_io_read(struct bio *bio, int err) +{ + __bounce_end_io_read(bio, page_pool, err); +} + +static void bounce_end_io_read_isa(struct bio *bio, int err) +{ + __bounce_end_io_read(bio, isa_page_pool, err); +} + +#ifdef CONFIG_NEED_BOUNCE_POOL +static int must_snapshot_stable_pages(struct request_queue *q, struct bio *bio) +{ + if (bio_data_dir(bio) != WRITE) + return 0; + + if (!bdi_cap_stable_pages_required(&q->backing_dev_info)) + return 0; + + return test_bit(BIO_SNAP_STABLE, &bio->bi_flags); +} +#else +static int must_snapshot_stable_pages(struct request_queue *q, struct bio *bio) +{ + return 0; +} +#endif /* CONFIG_NEED_BOUNCE_POOL */ + +static void __blk_queue_bounce(struct request_queue *q, struct bio **bio_orig, + mempool_t *pool, int force) +{ + struct bio *bio; + int rw = bio_data_dir(*bio_orig); + struct bio_vec *to, from; + struct bvec_iter iter; + unsigned i; + + if (force) + goto bounce; + bio_for_each_segment(from, *bio_orig, iter) + if (page_to_pfn(from.bv_page) > queue_bounce_pfn(q)) + goto bounce; + + return; +bounce: + bio = bio_clone_bioset(*bio_orig, GFP_NOIO, fs_bio_set); + + bio_for_each_segment_all(to, bio, i) { + struct page *page = to->bv_page; + + if (page_to_pfn(page) <= queue_bounce_pfn(q) && !force) + continue; + + inc_zone_page_state(to->bv_page, NR_BOUNCE); + to->bv_page = mempool_alloc(pool, q->bounce_gfp); + + if (rw == WRITE) { + char *vto, *vfrom; + + flush_dcache_page(page); + + vto = page_address(to->bv_page) + to->bv_offset; + vfrom = kmap_atomic(page) + to->bv_offset; + memcpy(vto, vfrom, to->bv_len); + kunmap_atomic(vfrom); + } + } + + trace_block_bio_bounce(q, *bio_orig); + + bio->bi_flags |= (1 << BIO_BOUNCED); + + if (pool == page_pool) { + bio->bi_end_io = bounce_end_io_write; + if (rw == READ) + bio->bi_end_io = bounce_end_io_read; + } else { + bio->bi_end_io = bounce_end_io_write_isa; + if (rw == READ) + bio->bi_end_io = bounce_end_io_read_isa; + } + + bio->bi_private = *bio_orig; + *bio_orig = bio; +} + +void blk_queue_bounce(struct request_queue *q, struct bio **bio_orig) +{ + int must_bounce; + mempool_t *pool; + + /* + * Data-less bio, nothing to bounce + */ + if (!bio_has_data(*bio_orig)) + return; + + must_bounce = must_snapshot_stable_pages(q, *bio_orig); + + /* + * for non-isa bounce case, just check if the bounce pfn is equal + * to or bigger than the highest pfn in the system -- in that case, + * don't waste time iterating over bio segments + */ + if (!(q->bounce_gfp & GFP_DMA)) { + if (queue_bounce_pfn(q) >= blk_max_pfn && !must_bounce) + return; + pool = page_pool; + } else { + BUG_ON(!isa_page_pool); + pool = isa_page_pool; + } + + /* + * slow path + */ + __blk_queue_bounce(q, bio_orig, pool, must_bounce); +} + +EXPORT_SYMBOL(blk_queue_bounce); diff --git a/block/bsg.c b/block/bsg.c index 420a5a9f1b2..ff46addde5d 100644 --- a/block/bsg.c +++ b/block/bsg.c @@ -196,7 +196,6 @@ static int blk_fill_sgv4_hdr_rq(struct request_queue *q, struct request *rq, * fill in request structure */ rq->cmd_len = hdr->request_len; - rq->cmd_type = REQ_TYPE_BLOCK_PC; rq->timeout = msecs_to_jiffies(hdr->timeout); if (!rq->timeout) @@ -273,6 +272,8 @@ bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, fmode_t has_write_perm, rq = blk_get_request(q, rw, GFP_KERNEL); if (!rq) return ERR_PTR(-ENOMEM); + blk_rq_set_block_pc(rq); + ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, bd, has_write_perm); if (ret) goto out; @@ -1008,7 +1009,7 @@ int bsg_register_queue(struct request_queue *q, struct device *parent, /* * we need a proper transport to send commands, not a stacked device */ - if (!q->request_fn) + if (!queue_is_rq_based(q)) return 0; bcd = &q->bsg_dev; diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index dabb9d02cf9..cadc3784174 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -908,7 +908,7 @@ static inline void cfq_schedule_dispatch(struct cfq_data *cfqd) { if (cfqd->busy_queues) { cfq_log(cfqd, "schedule dispatch"); - kblockd_schedule_work(cfqd->queue, &cfqd->unplug_work); + kblockd_schedule_work(&cfqd->unplug_work); } } @@ -1508,6 +1508,29 @@ static void cfq_init_cfqg_base(struct cfq_group *cfqg) } #ifdef CONFIG_CFQ_GROUP_IOSCHED +static void cfqg_stats_init(struct cfqg_stats *stats) +{ + blkg_rwstat_init(&stats->service_bytes); + blkg_rwstat_init(&stats->serviced); + blkg_rwstat_init(&stats->merged); + blkg_rwstat_init(&stats->service_time); + blkg_rwstat_init(&stats->wait_time); + blkg_rwstat_init(&stats->queued); + + blkg_stat_init(&stats->sectors); + blkg_stat_init(&stats->time); + +#ifdef CONFIG_DEBUG_BLK_CGROUP + blkg_stat_init(&stats->unaccounted_time); + blkg_stat_init(&stats->avg_queue_size_sum); + blkg_stat_init(&stats->avg_queue_size_samples); + blkg_stat_init(&stats->dequeue); + blkg_stat_init(&stats->group_wait_time); + blkg_stat_init(&stats->idle_time); + blkg_stat_init(&stats->empty_time); +#endif +} + static void cfq_pd_init(struct blkcg_gq *blkg) { struct cfq_group *cfqg = blkg_to_cfqg(blkg); @@ -1515,6 +1538,8 @@ static void cfq_pd_init(struct blkcg_gq *blkg) cfq_init_cfqg_base(cfqg); cfqg->weight = blkg->blkcg->cfq_weight; cfqg->leaf_weight = blkg->blkcg->cfq_leaf_weight; + cfqg_stats_init(&cfqg->stats); + cfqg_stats_init(&cfqg->dead_stats); } static void cfq_pd_offline(struct blkcg_gq *blkg) @@ -1607,11 +1632,11 @@ static u64 cfqg_prfill_weight_device(struct seq_file *sf, return __blkg_prfill_u64(sf, pd, cfqg->dev_weight); } -static int cfqg_print_weight_device(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *sf) +static int cfqg_print_weight_device(struct seq_file *sf, void *v) { - blkcg_print_blkgs(sf, css_to_blkcg(css), cfqg_prfill_weight_device, - &blkcg_policy_cfq, 0, false); + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), + cfqg_prfill_weight_device, &blkcg_policy_cfq, + 0, false); return 0; } @@ -1625,34 +1650,31 @@ static u64 cfqg_prfill_leaf_weight_device(struct seq_file *sf, return __blkg_prfill_u64(sf, pd, cfqg->dev_leaf_weight); } -static int cfqg_print_leaf_weight_device(struct cgroup_subsys_state *css, - struct cftype *cft, - struct seq_file *sf) +static int cfqg_print_leaf_weight_device(struct seq_file *sf, void *v) { - blkcg_print_blkgs(sf, css_to_blkcg(css), cfqg_prfill_leaf_weight_device, - &blkcg_policy_cfq, 0, false); + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), + cfqg_prfill_leaf_weight_device, &blkcg_policy_cfq, + 0, false); return 0; } -static int cfq_print_weight(struct cgroup_subsys_state *css, struct cftype *cft, - struct seq_file *sf) +static int cfq_print_weight(struct seq_file *sf, void *v) { - seq_printf(sf, "%u\n", css_to_blkcg(css)->cfq_weight); + seq_printf(sf, "%u\n", css_to_blkcg(seq_css(sf))->cfq_weight); return 0; } -static int cfq_print_leaf_weight(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *sf) +static int cfq_print_leaf_weight(struct seq_file *sf, void *v) { - seq_printf(sf, "%u\n", css_to_blkcg(css)->cfq_leaf_weight); + seq_printf(sf, "%u\n", css_to_blkcg(seq_css(sf))->cfq_leaf_weight); return 0; } -static int __cfqg_set_weight_device(struct cgroup_subsys_state *css, - struct cftype *cft, const char *buf, - bool is_leaf_weight) +static ssize_t __cfqg_set_weight_device(struct kernfs_open_file *of, + char *buf, size_t nbytes, loff_t off, + bool is_leaf_weight) { - struct blkcg *blkcg = css_to_blkcg(css); + struct blkcg *blkcg = css_to_blkcg(of_css(of)); struct blkg_conf_ctx ctx; struct cfq_group *cfqg; int ret; @@ -1675,19 +1697,19 @@ static int __cfqg_set_weight_device(struct cgroup_subsys_state *css, } blkg_conf_finish(&ctx); - return ret; + return ret ?: nbytes; } -static int cfqg_set_weight_device(struct cgroup_subsys_state *css, - struct cftype *cft, const char *buf) +static ssize_t cfqg_set_weight_device(struct kernfs_open_file *of, + char *buf, size_t nbytes, loff_t off) { - return __cfqg_set_weight_device(css, cft, buf, false); + return __cfqg_set_weight_device(of, buf, nbytes, off, false); } -static int cfqg_set_leaf_weight_device(struct cgroup_subsys_state *css, - struct cftype *cft, const char *buf) +static ssize_t cfqg_set_leaf_weight_device(struct kernfs_open_file *of, + char *buf, size_t nbytes, loff_t off) { - return __cfqg_set_weight_device(css, cft, buf, true); + return __cfqg_set_weight_device(of, buf, nbytes, off, true); } static int __cfq_set_weight(struct cgroup_subsys_state *css, struct cftype *cft, @@ -1737,23 +1759,17 @@ static int cfq_set_leaf_weight(struct cgroup_subsys_state *css, return __cfq_set_weight(css, cft, val, true); } -static int cfqg_print_stat(struct cgroup_subsys_state *css, struct cftype *cft, - struct seq_file *sf) +static int cfqg_print_stat(struct seq_file *sf, void *v) { - struct blkcg *blkcg = css_to_blkcg(css); - - blkcg_print_blkgs(sf, blkcg, blkg_prfill_stat, &blkcg_policy_cfq, - cft->private, false); + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), blkg_prfill_stat, + &blkcg_policy_cfq, seq_cft(sf)->private, false); return 0; } -static int cfqg_print_rwstat(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *sf) +static int cfqg_print_rwstat(struct seq_file *sf, void *v) { - struct blkcg *blkcg = css_to_blkcg(css); - - blkcg_print_blkgs(sf, blkcg, blkg_prfill_rwstat, &blkcg_policy_cfq, - cft->private, true); + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), blkg_prfill_rwstat, + &blkcg_policy_cfq, seq_cft(sf)->private, true); return 0; } @@ -1773,23 +1789,19 @@ static u64 cfqg_prfill_rwstat_recursive(struct seq_file *sf, return __blkg_prfill_rwstat(sf, pd, &sum); } -static int cfqg_print_stat_recursive(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *sf) +static int cfqg_print_stat_recursive(struct seq_file *sf, void *v) { - struct blkcg *blkcg = css_to_blkcg(css); - - blkcg_print_blkgs(sf, blkcg, cfqg_prfill_stat_recursive, - &blkcg_policy_cfq, cft->private, false); + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), + cfqg_prfill_stat_recursive, &blkcg_policy_cfq, + seq_cft(sf)->private, false); return 0; } -static int cfqg_print_rwstat_recursive(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *sf) +static int cfqg_print_rwstat_recursive(struct seq_file *sf, void *v) { - struct blkcg *blkcg = css_to_blkcg(css); - - blkcg_print_blkgs(sf, blkcg, cfqg_prfill_rwstat_recursive, - &blkcg_policy_cfq, cft->private, true); + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), + cfqg_prfill_rwstat_recursive, &blkcg_policy_cfq, + seq_cft(sf)->private, true); return 0; } @@ -1803,20 +1815,18 @@ static u64 cfqg_prfill_avg_queue_size(struct seq_file *sf, if (samples) { v = blkg_stat_read(&cfqg->stats.avg_queue_size_sum); - do_div(v, samples); + v = div64_u64(v, samples); } __blkg_prfill_u64(sf, pd, v); return 0; } /* print avg_queue_size */ -static int cfqg_print_avg_queue_size(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *sf) +static int cfqg_print_avg_queue_size(struct seq_file *sf, void *v) { - struct blkcg *blkcg = css_to_blkcg(css); - - blkcg_print_blkgs(sf, blkcg, cfqg_prfill_avg_queue_size, - &blkcg_policy_cfq, 0, false); + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), + cfqg_prfill_avg_queue_size, &blkcg_policy_cfq, + 0, false); return 0; } #endif /* CONFIG_DEBUG_BLK_CGROUP */ @@ -1826,14 +1836,13 @@ static struct cftype cfq_blkcg_files[] = { { .name = "weight_device", .flags = CFTYPE_ONLY_ON_ROOT, - .read_seq_string = cfqg_print_leaf_weight_device, - .write_string = cfqg_set_leaf_weight_device, - .max_write_len = 256, + .seq_show = cfqg_print_leaf_weight_device, + .write = cfqg_set_leaf_weight_device, }, { .name = "weight", .flags = CFTYPE_ONLY_ON_ROOT, - .read_seq_string = cfq_print_leaf_weight, + .seq_show = cfq_print_leaf_weight, .write_u64 = cfq_set_leaf_weight, }, @@ -1841,26 +1850,24 @@ static struct cftype cfq_blkcg_files[] = { { .name = "weight_device", .flags = CFTYPE_NOT_ON_ROOT, - .read_seq_string = cfqg_print_weight_device, - .write_string = cfqg_set_weight_device, - .max_write_len = 256, + .seq_show = cfqg_print_weight_device, + .write = cfqg_set_weight_device, }, { .name = "weight", .flags = CFTYPE_NOT_ON_ROOT, - .read_seq_string = cfq_print_weight, + .seq_show = cfq_print_weight, .write_u64 = cfq_set_weight, }, { .name = "leaf_weight_device", - .read_seq_string = cfqg_print_leaf_weight_device, - .write_string = cfqg_set_leaf_weight_device, - .max_write_len = 256, + .seq_show = cfqg_print_leaf_weight_device, + .write = cfqg_set_leaf_weight_device, }, { .name = "leaf_weight", - .read_seq_string = cfq_print_leaf_weight, + .seq_show = cfq_print_leaf_weight, .write_u64 = cfq_set_leaf_weight, }, @@ -1868,114 +1875,114 @@ static struct cftype cfq_blkcg_files[] = { { .name = "time", .private = offsetof(struct cfq_group, stats.time), - .read_seq_string = cfqg_print_stat, + .seq_show = cfqg_print_stat, }, { .name = "sectors", .private = offsetof(struct cfq_group, stats.sectors), - .read_seq_string = cfqg_print_stat, + .seq_show = cfqg_print_stat, }, { .name = "io_service_bytes", .private = offsetof(struct cfq_group, stats.service_bytes), - .read_seq_string = cfqg_print_rwstat, + .seq_show = cfqg_print_rwstat, }, { .name = "io_serviced", .private = offsetof(struct cfq_group, stats.serviced), - .read_seq_string = cfqg_print_rwstat, + .seq_show = cfqg_print_rwstat, }, { .name = "io_service_time", .private = offsetof(struct cfq_group, stats.service_time), - .read_seq_string = cfqg_print_rwstat, + .seq_show = cfqg_print_rwstat, }, { .name = "io_wait_time", .private = offsetof(struct cfq_group, stats.wait_time), - .read_seq_string = cfqg_print_rwstat, + .seq_show = cfqg_print_rwstat, }, { .name = "io_merged", .private = offsetof(struct cfq_group, stats.merged), - .read_seq_string = cfqg_print_rwstat, + .seq_show = cfqg_print_rwstat, }, { .name = "io_queued", .private = offsetof(struct cfq_group, stats.queued), - .read_seq_string = cfqg_print_rwstat, + .seq_show = cfqg_print_rwstat, }, /* the same statictics which cover the cfqg and its descendants */ { .name = "time_recursive", .private = offsetof(struct cfq_group, stats.time), - .read_seq_string = cfqg_print_stat_recursive, + .seq_show = cfqg_print_stat_recursive, }, { .name = "sectors_recursive", .private = offsetof(struct cfq_group, stats.sectors), - .read_seq_string = cfqg_print_stat_recursive, + .seq_show = cfqg_print_stat_recursive, }, { .name = "io_service_bytes_recursive", .private = offsetof(struct cfq_group, stats.service_bytes), - .read_seq_string = cfqg_print_rwstat_recursive, + .seq_show = cfqg_print_rwstat_recursive, }, { .name = "io_serviced_recursive", .private = offsetof(struct cfq_group, stats.serviced), - .read_seq_string = cfqg_print_rwstat_recursive, + .seq_show = cfqg_print_rwstat_recursive, }, { .name = "io_service_time_recursive", .private = offsetof(struct cfq_group, stats.service_time), - .read_seq_string = cfqg_print_rwstat_recursive, + .seq_show = cfqg_print_rwstat_recursive, }, { .name = "io_wait_time_recursive", .private = offsetof(struct cfq_group, stats.wait_time), - .read_seq_string = cfqg_print_rwstat_recursive, + .seq_show = cfqg_print_rwstat_recursive, }, { .name = "io_merged_recursive", .private = offsetof(struct cfq_group, stats.merged), - .read_seq_string = cfqg_print_rwstat_recursive, + .seq_show = cfqg_print_rwstat_recursive, }, { .name = "io_queued_recursive", .private = offsetof(struct cfq_group, stats.queued), - .read_seq_string = cfqg_print_rwstat_recursive, + .seq_show = cfqg_print_rwstat_recursive, }, #ifdef CONFIG_DEBUG_BLK_CGROUP { .name = "avg_queue_size", - .read_seq_string = cfqg_print_avg_queue_size, + .seq_show = cfqg_print_avg_queue_size, }, { .name = "group_wait_time", .private = offsetof(struct cfq_group, stats.group_wait_time), - .read_seq_string = cfqg_print_stat, + .seq_show = cfqg_print_stat, }, { .name = "idle_time", .private = offsetof(struct cfq_group, stats.idle_time), - .read_seq_string = cfqg_print_stat, + .seq_show = cfqg_print_stat, }, { .name = "empty_time", .private = offsetof(struct cfq_group, stats.empty_time), - .read_seq_string = cfqg_print_stat, + .seq_show = cfqg_print_stat, }, { .name = "dequeue", .private = offsetof(struct cfq_group, stats.dequeue), - .read_seq_string = cfqg_print_stat, + .seq_show = cfqg_print_stat, }, { .name = "unaccounted_time", .private = offsetof(struct cfq_group, stats.unaccounted_time), - .read_seq_string = cfqg_print_stat, + .seq_show = cfqg_print_stat, }, #endif /* CONFIG_DEBUG_BLK_CGROUP */ { } /* terminate */ @@ -2357,10 +2364,10 @@ cfq_merged_requests(struct request_queue *q, struct request *rq, * reposition in fifo if next is older than rq */ if (!list_empty(&rq->queuelist) && !list_empty(&next->queuelist) && - time_before(rq_fifo_time(next), rq_fifo_time(rq)) && + time_before(next->fifo_time, rq->fifo_time) && cfqq == RQ_CFQQ(next)) { list_move(&rq->queuelist, &next->queuelist); - rq_set_fifo_time(rq, rq_fifo_time(next)); + rq->fifo_time = next->fifo_time; } if (cfqq->next_rq == next) @@ -2804,7 +2811,7 @@ static struct request *cfq_check_fifo(struct cfq_queue *cfqq) return NULL; rq = rq_entry_fifo(cfqq->fifo.next); - if (time_before(jiffies, rq_fifo_time(rq))) + if (time_before(jiffies, rq->fifo_time)) rq = NULL; cfq_log_cfqq(cfqq->cfqd, cfqq, "fifo=%p", rq); @@ -3917,7 +3924,7 @@ static void cfq_insert_request(struct request_queue *q, struct request *rq) cfq_log_cfqq(cfqd, cfqq, "insert_request"); cfq_init_prio_data(cfqq, RQ_CIC(rq)); - rq_set_fifo_time(rq, jiffies + cfqd->cfq_fifo_expire[rq_is_sync(rq)]); + rq->fifo_time = jiffies + cfqd->cfq_fifo_expire[rq_is_sync(rq)]; list_add_tail(&rq->queuelist, &cfqq->fifo); cfq_add_rq_rb(rq); cfqg_stats_update_io_add(RQ_CFQG(rq), cfqd->serving_group, @@ -4358,7 +4365,7 @@ static int cfq_init_queue(struct request_queue *q, struct elevator_type *e) if (!eq) return -ENOMEM; - cfqd = kmalloc_node(sizeof(*cfqd), GFP_KERNEL | __GFP_ZERO, q->node); + cfqd = kzalloc_node(sizeof(*cfqd), GFP_KERNEL, q->node); if (!cfqd) { kobject_put(&eq->kobj); return -ENOMEM; @@ -4453,7 +4460,7 @@ out_free: static ssize_t cfq_var_show(unsigned int var, char *page) { - return sprintf(page, "%d\n", var); + return sprintf(page, "%u\n", var); } static ssize_t diff --git a/block/cmdline-parser.c b/block/cmdline-parser.c index cc2637f8674..9dbc67e42a9 100644 --- a/block/cmdline-parser.c +++ b/block/cmdline-parser.c @@ -4,8 +4,7 @@ * Written by Cai Zhiyong <caizhiyong@huawei.com> * */ -#include <linux/buffer_head.h> -#include <linux/module.h> +#include <linux/export.h> #include <linux/cmdline-parser.h> static int parse_subpart(struct cmdline_subpart **subpart, char *partdef) @@ -159,6 +158,7 @@ void cmdline_parts_free(struct cmdline_parts **parts) *parts = next_parts; } } +EXPORT_SYMBOL(cmdline_parts_free); int cmdline_parts_parse(struct cmdline_parts **parts, const char *cmdline) { @@ -206,6 +206,7 @@ fail: cmdline_parts_free(parts); goto done; } +EXPORT_SYMBOL(cmdline_parts_parse); struct cmdline_parts *cmdline_parts_find(struct cmdline_parts *parts, const char *bdev) @@ -214,17 +215,17 @@ struct cmdline_parts *cmdline_parts_find(struct cmdline_parts *parts, parts = parts->next_parts; return parts; } +EXPORT_SYMBOL(cmdline_parts_find); /* * add_part() * 0 success. * 1 can not add so many partitions. */ -void cmdline_parts_set(struct cmdline_parts *parts, sector_t disk_size, - int slot, - int (*add_part)(int, struct cmdline_subpart *, void *), - void *param) - +int cmdline_parts_set(struct cmdline_parts *parts, sector_t disk_size, + int slot, + int (*add_part)(int, struct cmdline_subpart *, void *), + void *param) { sector_t from = 0; struct cmdline_subpart *subpart; @@ -247,4 +248,7 @@ void cmdline_parts_set(struct cmdline_parts *parts, sector_t disk_size, if (add_part(slot, subpart, param)) break; } + + return slot; } +EXPORT_SYMBOL(cmdline_parts_set); diff --git a/block/compat_ioctl.c b/block/compat_ioctl.c index fbd5a67cb77..a0926a6094b 100644 --- a/block/compat_ioctl.c +++ b/block/compat_ioctl.c @@ -690,6 +690,7 @@ long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg) case BLKROSET: case BLKDISCARD: case BLKSECDISCARD: + case BLKZEROOUT: /* * the ones below are implemented in blkdev_locked_ioctl, * but we call blkdev_ioctl, which gets the lock for us diff --git a/block/deadline-iosched.c b/block/deadline-iosched.c index 20614a33236..a753df2b3fc 100644 --- a/block/deadline-iosched.c +++ b/block/deadline-iosched.c @@ -106,7 +106,7 @@ deadline_add_request(struct request_queue *q, struct request *rq) /* * set expire time and add to fifo list */ - rq_set_fifo_time(rq, jiffies + dd->fifo_expire[data_dir]); + rq->fifo_time = jiffies + dd->fifo_expire[data_dir]; list_add_tail(&rq->queuelist, &dd->fifo_list[data_dir]); } @@ -174,9 +174,9 @@ deadline_merged_requests(struct request_queue *q, struct request *req, * and move into next position (next will be deleted) in fifo */ if (!list_empty(&req->queuelist) && !list_empty(&next->queuelist)) { - if (time_before(rq_fifo_time(next), rq_fifo_time(req))) { + if (time_before(next->fifo_time, req->fifo_time)) { list_move(&req->queuelist, &next->queuelist); - rq_set_fifo_time(req, rq_fifo_time(next)); + req->fifo_time = next->fifo_time; } } @@ -230,7 +230,7 @@ static inline int deadline_check_fifo(struct deadline_data *dd, int ddir) /* * rq is expired! */ - if (time_after_eq(jiffies, rq_fifo_time(rq))) + if (time_after_eq(jiffies, rq->fifo_time)) return 1; return 0; @@ -346,7 +346,7 @@ static int deadline_init_queue(struct request_queue *q, struct elevator_type *e) if (!eq) return -ENOMEM; - dd = kmalloc_node(sizeof(*dd), GFP_KERNEL | __GFP_ZERO, q->node); + dd = kzalloc_node(sizeof(*dd), GFP_KERNEL, q->node); if (!dd) { kobject_put(&eq->kobj); return -ENOMEM; diff --git a/block/elevator.c b/block/elevator.c index 668394d1858..24c28b659bb 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -155,7 +155,7 @@ struct elevator_queue *elevator_alloc(struct request_queue *q, { struct elevator_queue *eq; - eq = kmalloc_node(sizeof(*eq), GFP_KERNEL | __GFP_ZERO, q->node); + eq = kzalloc_node(sizeof(*eq), GFP_KERNEL, q->node); if (unlikely(!eq)) goto err; @@ -186,6 +186,12 @@ int elevator_init(struct request_queue *q, char *name) struct elevator_type *e = NULL; int err; + /* + * q->sysfs_lock must be held to provide mutual exclusion between + * elevator_switch() and here. + */ + lockdep_assert_held(&q->sysfs_lock); + if (unlikely(q->elevator)) return 0; @@ -241,6 +247,7 @@ EXPORT_SYMBOL(elevator_exit); static inline void __elv_rqhash_del(struct request *rq) { hash_del(&rq->hash); + rq->cmd_flags &= ~REQ_HASHED; } static void elv_rqhash_del(struct request_queue *q, struct request *rq) @@ -255,6 +262,7 @@ static void elv_rqhash_add(struct request_queue *q, struct request *rq) BUG_ON(ELV_ON_HASH(rq)); hash_add(e->hash, &rq->hash, rq_hash_key(rq)); + rq->cmd_flags |= REQ_HASHED; } static void elv_rqhash_reposition(struct request_queue *q, struct request *rq) @@ -434,7 +442,7 @@ int elv_merge(struct request_queue *q, struct request **req, struct bio *bio) /* * See if our hash lookup can find a potential backmerge. */ - __rq = elv_rqhash_find(q, bio->bi_sector); + __rq = elv_rqhash_find(q, bio->bi_iter.bi_sector); if (__rq && elv_rq_merge_ok(__rq, bio)) { *req = __rq; return ELEVATOR_BACK_MERGE; @@ -721,26 +729,6 @@ int elv_may_queue(struct request_queue *q, int rw) return ELV_MQUEUE_MAY; } -void elv_abort_queue(struct request_queue *q) -{ - struct request *rq; - - blk_abort_flushes(q); - - while (!list_empty(&q->queue_head)) { - rq = list_entry_rq(q->queue_head.next); - rq->cmd_flags |= REQ_QUIET; - trace_block_rq_abort(q, rq); - /* - * Mark this request as started so we don't trigger - * any debug logic in the end I/O path. - */ - blk_start_request(rq); - __blk_end_request_all(rq, -EIO); - } -} -EXPORT_SYMBOL(elv_abort_queue); - void elv_completed_request(struct request_queue *q, struct request *rq) { struct elevator_queue *e = q->elevator; @@ -959,7 +947,7 @@ fail_init: /* * Switch this queue to the given IO scheduler. */ -int elevator_change(struct request_queue *q, const char *name) +static int __elevator_change(struct request_queue *q, const char *name) { char elevator_name[ELV_NAME_MAX]; struct elevator_type *e; @@ -981,6 +969,18 @@ int elevator_change(struct request_queue *q, const char *name) return elevator_switch(q, e); } + +int elevator_change(struct request_queue *q, const char *name) +{ + int ret; + + /* Protect q->elevator from elevator_init() */ + mutex_lock(&q->sysfs_lock); + ret = __elevator_change(q, name); + mutex_unlock(&q->sysfs_lock); + + return ret; +} EXPORT_SYMBOL(elevator_change); ssize_t elv_iosched_store(struct request_queue *q, const char *name, @@ -991,7 +991,7 @@ ssize_t elv_iosched_store(struct request_queue *q, const char *name, if (!q->elevator) return count; - ret = elevator_change(q, name); + ret = __elevator_change(q, name); if (!ret) return count; diff --git a/block/genhd.c b/block/genhd.c index dadf42b454a..791f4194313 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -1252,8 +1252,7 @@ struct gendisk *alloc_disk_node(int minors, int node_id) { struct gendisk *disk; - disk = kmalloc_node(sizeof(struct gendisk), - GFP_KERNEL | __GFP_ZERO, node_id); + disk = kzalloc_node(sizeof(struct gendisk), GFP_KERNEL, node_id); if (disk) { if (!init_part_stats(&disk->part0)) { kfree(disk); diff --git a/block/ioctl.c b/block/ioctl.c index a31d91d9bc5..7d5c3b20af4 100644 --- a/block/ioctl.c +++ b/block/ioctl.c @@ -64,7 +64,7 @@ static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user part = add_partition(disk, partno, start, length, ADDPART_FLAG_NONE, NULL); mutex_unlock(&bdev->bd_mutex); - return IS_ERR(part) ? PTR_ERR(part) : 0; + return PTR_ERR_OR_ZERO(part); case BLKPG_DEL_PARTITION: part = disk_get_part(disk, partno); if (!part) diff --git a/block/ioprio.c b/block/ioprio.c new file mode 100644 index 00000000000..e50170ca7c3 --- /dev/null +++ b/block/ioprio.c @@ -0,0 +1,241 @@ +/* + * fs/ioprio.c + * + * Copyright (C) 2004 Jens Axboe <axboe@kernel.dk> + * + * Helper functions for setting/querying io priorities of processes. The + * system calls closely mimmick getpriority/setpriority, see the man page for + * those. The prio argument is a composite of prio class and prio data, where + * the data argument has meaning within that class. The standard scheduling + * classes have 8 distinct prio levels, with 0 being the highest prio and 7 + * being the lowest. + * + * IOW, setting BE scheduling class with prio 2 is done ala: + * + * unsigned int prio = (IOPRIO_CLASS_BE << IOPRIO_CLASS_SHIFT) | 2; + * + * ioprio_set(PRIO_PROCESS, pid, prio); + * + * See also Documentation/block/ioprio.txt + * + */ +#include <linux/gfp.h> +#include <linux/kernel.h> +#include <linux/export.h> +#include <linux/ioprio.h> +#include <linux/blkdev.h> +#include <linux/capability.h> +#include <linux/syscalls.h> +#include <linux/security.h> +#include <linux/pid_namespace.h> + +int set_task_ioprio(struct task_struct *task, int ioprio) +{ + int err; + struct io_context *ioc; + const struct cred *cred = current_cred(), *tcred; + + rcu_read_lock(); + tcred = __task_cred(task); + if (!uid_eq(tcred->uid, cred->euid) && + !uid_eq(tcred->uid, cred->uid) && !capable(CAP_SYS_NICE)) { + rcu_read_unlock(); + return -EPERM; + } + rcu_read_unlock(); + + err = security_task_setioprio(task, ioprio); + if (err) + return err; + + ioc = get_task_io_context(task, GFP_ATOMIC, NUMA_NO_NODE); + if (ioc) { + ioc->ioprio = ioprio; + put_io_context(ioc); + } + + return err; +} +EXPORT_SYMBOL_GPL(set_task_ioprio); + +SYSCALL_DEFINE3(ioprio_set, int, which, int, who, int, ioprio) +{ + int class = IOPRIO_PRIO_CLASS(ioprio); + int data = IOPRIO_PRIO_DATA(ioprio); + struct task_struct *p, *g; + struct user_struct *user; + struct pid *pgrp; + kuid_t uid; + int ret; + + switch (class) { + case IOPRIO_CLASS_RT: + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + /* fall through, rt has prio field too */ + case IOPRIO_CLASS_BE: + if (data >= IOPRIO_BE_NR || data < 0) + return -EINVAL; + + break; + case IOPRIO_CLASS_IDLE: + break; + case IOPRIO_CLASS_NONE: + if (data) + return -EINVAL; + break; + default: + return -EINVAL; + } + + ret = -ESRCH; + rcu_read_lock(); + switch (which) { + case IOPRIO_WHO_PROCESS: + if (!who) + p = current; + else + p = find_task_by_vpid(who); + if (p) + ret = set_task_ioprio(p, ioprio); + break; + case IOPRIO_WHO_PGRP: + if (!who) + pgrp = task_pgrp(current); + else + pgrp = find_vpid(who); + do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { + ret = set_task_ioprio(p, ioprio); + if (ret) + break; + } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); + break; + case IOPRIO_WHO_USER: + uid = make_kuid(current_user_ns(), who); + if (!uid_valid(uid)) + break; + if (!who) + user = current_user(); + else + user = find_user(uid); + + if (!user) + break; + + do_each_thread(g, p) { + if (!uid_eq(task_uid(p), uid)) + continue; + ret = set_task_ioprio(p, ioprio); + if (ret) + goto free_uid; + } while_each_thread(g, p); +free_uid: + if (who) + free_uid(user); + break; + default: + ret = -EINVAL; + } + + rcu_read_unlock(); + return ret; +} + +static int get_task_ioprio(struct task_struct *p) +{ + int ret; + + ret = security_task_getioprio(p); + if (ret) + goto out; + ret = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_NONE, IOPRIO_NORM); + if (p->io_context) + ret = p->io_context->ioprio; +out: + return ret; +} + +int ioprio_best(unsigned short aprio, unsigned short bprio) +{ + unsigned short aclass = IOPRIO_PRIO_CLASS(aprio); + unsigned short bclass = IOPRIO_PRIO_CLASS(bprio); + + if (aclass == IOPRIO_CLASS_NONE) + aclass = IOPRIO_CLASS_BE; + if (bclass == IOPRIO_CLASS_NONE) + bclass = IOPRIO_CLASS_BE; + + if (aclass == bclass) + return min(aprio, bprio); + if (aclass > bclass) + return bprio; + else + return aprio; +} + +SYSCALL_DEFINE2(ioprio_get, int, which, int, who) +{ + struct task_struct *g, *p; + struct user_struct *user; + struct pid *pgrp; + kuid_t uid; + int ret = -ESRCH; + int tmpio; + + rcu_read_lock(); + switch (which) { + case IOPRIO_WHO_PROCESS: + if (!who) + p = current; + else + p = find_task_by_vpid(who); + if (p) + ret = get_task_ioprio(p); + break; + case IOPRIO_WHO_PGRP: + if (!who) + pgrp = task_pgrp(current); + else + pgrp = find_vpid(who); + do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { + tmpio = get_task_ioprio(p); + if (tmpio < 0) + continue; + if (ret == -ESRCH) + ret = tmpio; + else + ret = ioprio_best(ret, tmpio); + } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); + break; + case IOPRIO_WHO_USER: + uid = make_kuid(current_user_ns(), who); + if (!who) + user = current_user(); + else + user = find_user(uid); + + if (!user) + break; + + do_each_thread(g, p) { + if (!uid_eq(task_uid(p), user->uid)) + continue; + tmpio = get_task_ioprio(p); + if (tmpio < 0) + continue; + if (ret == -ESRCH) + ret = tmpio; + else + ret = ioprio_best(ret, tmpio); + } while_each_thread(g, p); + + if (who) + free_uid(user); + break; + default: + ret = -EINVAL; + } + + rcu_read_unlock(); + return ret; +} diff --git a/block/partitions/Kconfig b/block/partitions/Kconfig index 87a32086535..9b29a996c31 100644 --- a/block/partitions/Kconfig +++ b/block/partitions/Kconfig @@ -263,7 +263,7 @@ config SYSV68_PARTITION config CMDLINE_PARTITION bool "Command line partition support" if PARTITION_ADVANCED - select CMDLINE_PARSER + select BLK_CMDLINE_PARSER help - Say Y here if you would read the partitions table from bootargs. + Say Y here if you want to read the partition table from bootargs. The format for the command line is just like mtdparts. diff --git a/block/partitions/atari.h b/block/partitions/atari.h index fe2d32a89f3..f2ec43bfeec 100644 --- a/block/partitions/atari.h +++ b/block/partitions/atari.h @@ -11,6 +11,8 @@ * by Guenther Kelleter (guenther@pool.informatik.rwth-aachen.de) */ +#include <linux/compiler.h> + struct partition_info { u8 flg; /* bit 0: active; bit 7: bootable */ @@ -29,6 +31,6 @@ struct rootsector u32 bsl_st; /* start of bad sector list */ u32 bsl_cnt; /* length of bad sector list */ u16 checksum; /* checksum for bootable disks */ -} __attribute__((__packed__)); +} __packed; int atari_partition(struct parsed_partitions *state); diff --git a/block/partitions/cmdline.c b/block/partitions/cmdline.c index 56cf4ffad51..5141b563adf 100644 --- a/block/partitions/cmdline.c +++ b/block/partitions/cmdline.c @@ -2,15 +2,15 @@ * Copyright (C) 2013 HUAWEI * Author: Cai Zhiyong <caizhiyong@huawei.com> * - * Read block device partition table from command line. - * The partition used for fixed block device (eMMC) embedded device. - * It is no MBR, save storage space. Bootloader can be easily accessed + * Read block device partition table from the command line. + * Typically used for fixed block (eMMC) embedded devices. + * It has no MBR, so saves storage space. Bootloader can be easily accessed * by absolute address of data on the block device. * Users can easily change the partition. * * The format for the command line is just like mtdparts. * - * Verbose config please reference "Documentation/block/cmdline-partition.txt" + * For further information, see "Documentation/block/cmdline-partition.txt" * */ diff --git a/block/partitions/efi.c b/block/partitions/efi.c index 1eb09ee5311..dc51f467a56 100644 --- a/block/partitions/efi.c +++ b/block/partitions/efi.c @@ -96,6 +96,7 @@ * - Code works, detects all the partitions. * ************************************************************/ +#include <linux/kernel.h> #include <linux/crc32.h> #include <linux/ctype.h> #include <linux/math64.h> @@ -222,11 +223,16 @@ check_hybrid: * the disk size. * * Hybrid MBRs do not necessarily comply with this. + * + * Consider a bad value here to be a warning to support dd'ing + * an image from a smaller disk to a larger disk. */ if (ret == GPT_MBR_PROTECTIVE) { sz = le32_to_cpu(mbr->partition_record[part].size_in_lba); if (sz != (uint32_t) total_sectors - 1 && sz != 0xFFFFFFFF) - ret = 0; + pr_debug("GPT: mbr size in lba (%u) different than whole disk (%u).\n", + sz, min_t(uint32_t, + total_sectors - 1, 0xFFFFFFFF)); } done: return ret; @@ -710,8 +716,8 @@ int efi_partition(struct parsed_partitions *state) efi_guid_unparse(&ptes[i].unique_partition_guid, info->uuid); /* Naively convert UTF16-LE to 7 bits. */ - label_max = min(sizeof(info->volname) - 1, - sizeof(ptes[i].partition_name)); + label_max = min(ARRAY_SIZE(info->volname) - 1, + ARRAY_SIZE(ptes[i].partition_name)); info->volname[label_max] = 0; while (label_count < label_max) { u8 c = ptes[i].partition_name[label_count] & 0xff; diff --git a/block/partitions/efi.h b/block/partitions/efi.h index 4efcafba7e6..abd0b19288a 100644 --- a/block/partitions/efi.h +++ b/block/partitions/efi.h @@ -32,6 +32,7 @@ #include <linux/major.h> #include <linux/string.h> #include <linux/efi.h> +#include <linux/compiler.h> #define MSDOS_MBR_SIGNATURE 0xaa55 #define EFI_PMBR_OSTYPE_EFI 0xEF @@ -87,13 +88,13 @@ typedef struct _gpt_header { * * uint8_t reserved2[ BlockSize - 92 ]; */ -} __attribute__ ((packed)) gpt_header; +} __packed gpt_header; typedef struct _gpt_entry_attributes { u64 required_to_function:1; u64 reserved:47; u64 type_guid_specific:16; -} __attribute__ ((packed)) gpt_entry_attributes; +} __packed gpt_entry_attributes; typedef struct _gpt_entry { efi_guid_t partition_type_guid; @@ -102,7 +103,7 @@ typedef struct _gpt_entry { __le64 ending_lba; gpt_entry_attributes attributes; efi_char16_t partition_name[72 / sizeof (efi_char16_t)]; -} __attribute__ ((packed)) gpt_entry; +} __packed gpt_entry; typedef struct _gpt_mbr_record { u8 boot_indicator; /* unused by EFI, set to 0x80 for bootable */ @@ -124,7 +125,7 @@ typedef struct _legacy_mbr { __le16 unknown; gpt_mbr_record partition_record[4]; __le16 signature; -} __attribute__ ((packed)) legacy_mbr; +} __packed legacy_mbr; /* Functions */ extern int efi_partition(struct parsed_partitions *state); diff --git a/block/partitions/karma.c b/block/partitions/karma.c index 0ea19312706..9721fa589bb 100644 --- a/block/partitions/karma.c +++ b/block/partitions/karma.c @@ -8,6 +8,7 @@ #include "check.h" #include "karma.h" +#include <linux/compiler.h> int karma_partition(struct parsed_partitions *state) { @@ -26,7 +27,7 @@ int karma_partition(struct parsed_partitions *state) } d_partitions[2]; u8 d_blank[208]; __le16 d_magic; - } __attribute__((packed)) *label; + } __packed *label; struct d_partition *p; data = read_part_sector(state, 0, §); diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c index a5ffcc988f0..14695c6221c 100644 --- a/block/scsi_ioctl.c +++ b/block/scsi_ioctl.c @@ -205,10 +205,6 @@ int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm) if (capable(CAP_SYS_RAWIO)) return 0; - /* if there's no filter set, assume we're filtering everything out */ - if (!filter) - return -EPERM; - /* Anybody who can open the device can do a read-safe command */ if (test_bit(cmd[0], filter->read_ok)) return 0; @@ -233,7 +229,6 @@ static int blk_fill_sghdr_rq(struct request_queue *q, struct request *rq, * fill in request structure */ rq->cmd_len = hdr->cmd_len; - rq->cmd_type = REQ_TYPE_BLOCK_PC; rq->timeout = msecs_to_jiffies(hdr->timeout); if (!rq->timeout) @@ -286,7 +281,8 @@ static int sg_io(struct request_queue *q, struct gendisk *bd_disk, struct sg_io_hdr *hdr, fmode_t mode) { unsigned long start_time; - int writing = 0, ret = 0; + ssize_t ret = 0; + int writing = 0; struct request *rq; char sense[SCSI_SENSE_BUFFERSIZE]; struct bio *bio; @@ -314,6 +310,7 @@ static int sg_io(struct request_queue *q, struct gendisk *bd_disk, rq = blk_get_request(q, writing ? WRITE : READ, GFP_KERNEL); if (!rq) return -ENOMEM; + blk_rq_set_block_pc(rq); if (blk_fill_sghdr_rq(q, rq, hdr, mode)) { blk_put_request(rq); @@ -321,37 +318,18 @@ static int sg_io(struct request_queue *q, struct gendisk *bd_disk, } if (hdr->iovec_count) { - const int size = sizeof(struct sg_iovec) * hdr->iovec_count; size_t iov_data_len; - struct sg_iovec *sg_iov; - struct iovec *iov; - int i; - - sg_iov = kmalloc(size, GFP_KERNEL); - if (!sg_iov) { - ret = -ENOMEM; - goto out; - } + struct iovec *iov = NULL; - if (copy_from_user(sg_iov, hdr->dxferp, size)) { - kfree(sg_iov); - ret = -EFAULT; + ret = rw_copy_check_uvector(-1, hdr->dxferp, hdr->iovec_count, + 0, NULL, &iov); + if (ret < 0) { + kfree(iov); goto out; } - /* - * Sum up the vecs, making sure they don't overflow - */ - iov = (struct iovec *) sg_iov; - iov_data_len = 0; - for (i = 0; i < hdr->iovec_count; i++) { - if (iov_data_len + iov[i].iov_len < iov_data_len) { - kfree(sg_iov); - ret = -EINVAL; - goto out; - } - iov_data_len += iov[i].iov_len; - } + iov_data_len = ret; + ret = 0; /* SG_IO howto says that the shorter of the two wins */ if (hdr->dxfer_len < iov_data_len) { @@ -361,9 +339,10 @@ static int sg_io(struct request_queue *q, struct gendisk *bd_disk, iov_data_len = hdr->dxfer_len; } - ret = blk_rq_map_user_iov(q, rq, NULL, sg_iov, hdr->iovec_count, + ret = blk_rq_map_user_iov(q, rq, NULL, (struct sg_iovec *) iov, + hdr->iovec_count, iov_data_len, GFP_KERNEL); - kfree(sg_iov); + kfree(iov); } else if (hdr->dxfer_len) ret = blk_rq_map_user(q, rq, NULL, hdr->dxferp, hdr->dxfer_len, GFP_KERNEL); @@ -512,7 +491,7 @@ int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk, fmode_t mode, memset(sense, 0, sizeof(sense)); rq->sense = sense; rq->sense_len = 0; - rq->cmd_type = REQ_TYPE_BLOCK_PC; + blk_rq_set_block_pc(rq); blk_execute_rq(q, disk, rq, 0); @@ -545,7 +524,7 @@ static int __blk_send_generic(struct request_queue *q, struct gendisk *bd_disk, int err; rq = blk_get_request(q, WRITE, __GFP_WAIT); - rq->cmd_type = REQ_TYPE_BLOCK_PC; + blk_rq_set_block_pc(rq); rq->timeout = BLK_DEFAULT_SG_TIMEOUT; rq->cmd[0] = cmd; rq->cmd[4] = data; |