diff options
| -rw-r--r-- | fs/btrfs/Makefile | 2 | ||||
| -rw-r--r-- | fs/btrfs/ctree.h | 37 | ||||
| -rw-r--r-- | fs/btrfs/disk-io.c | 12 | ||||
| -rw-r--r-- | fs/btrfs/file-item.c | 8 | ||||
| -rw-r--r-- | fs/btrfs/inode.c | 2 | ||||
| -rw-r--r-- | fs/btrfs/ioctl.h | 37 | ||||
| -rw-r--r-- | fs/btrfs/relocation.c | 2 | ||||
| -rw-r--r-- | fs/btrfs/scrub.c | 1492 | ||||
| -rw-r--r-- | fs/btrfs/transaction.c | 3 | ||||
| -rw-r--r-- | fs/btrfs/tree-log.c | 6 | ||||
| -rw-r--r-- | fs/btrfs/volumes.c | 4 | ||||
| -rw-r--r-- | fs/btrfs/volumes.h | 6 |
12 files changed, 1600 insertions, 11 deletions
diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile index 31610ea73ae..8fda3133c1b 100644 --- a/fs/btrfs/Makefile +++ b/fs/btrfs/Makefile @@ -7,4 +7,4 @@ btrfs-y += super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \ extent_map.o sysfs.o struct-funcs.o xattr.o ordered-data.o \ extent_io.o volumes.o async-thread.o ioctl.o locking.o orphan.o \ export.o tree-log.o acl.o free-space-cache.o zlib.o lzo.o \ - compression.o delayed-ref.o relocation.o + compression.o delayed-ref.o relocation.o scrub.o diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 2e61fe1b6b8..31141ba6072 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -23,6 +23,7 @@ #include <linux/mm.h> #include <linux/highmem.h> #include <linux/fs.h> +#include <linux/rwsem.h> #include <linux/completion.h> #include <linux/backing-dev.h> #include <linux/wait.h> @@ -33,6 +34,7 @@ #include "extent_io.h" #include "extent_map.h" #include "async-thread.h" +#include "ioctl.h" struct btrfs_trans_handle; struct btrfs_transaction; @@ -510,6 +512,12 @@ struct btrfs_extent_item_v0 { /* use full backrefs for extent pointers in the block */ #define BTRFS_BLOCK_FLAG_FULL_BACKREF (1ULL << 8) +/* + * this flag is only used internally by scrub and may be changed at any time + * it is only declared here to avoid collisions + */ +#define BTRFS_EXTENT_FLAG_SUPER (1ULL << 48) + struct btrfs_tree_block_info { struct btrfs_disk_key key; u8 level; @@ -1077,6 +1085,17 @@ struct btrfs_fs_info { void *bdev_holder; + /* private scrub information */ + struct mutex scrub_lock; + atomic_t scrubs_running; + atomic_t scrub_pause_req; + atomic_t scrubs_paused; + atomic_t scrub_cancel_req; + wait_queue_head_t scrub_pause_wait; + struct rw_semaphore scrub_super_lock; + int scrub_workers_refcnt; + struct btrfs_workers scrub_workers; + /* filesystem state */ u64 fs_state; }; @@ -2472,8 +2491,8 @@ struct btrfs_csum_item *btrfs_lookup_csum(struct btrfs_trans_handle *trans, int btrfs_csum_truncate(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, u64 isize); -int btrfs_lookup_csums_range(struct btrfs_root *root, u64 start, - u64 end, struct list_head *list); +int btrfs_lookup_csums_range(struct btrfs_root *root, u64 start, u64 end, + struct list_head *list, int search_commit); /* inode.c */ /* RHEL and EL kernels have a patch that renames PG_checked to FsMisc */ @@ -2637,4 +2656,18 @@ void btrfs_reloc_pre_snapshot(struct btrfs_trans_handle *trans, u64 *bytes_to_reserve); void btrfs_reloc_post_snapshot(struct btrfs_trans_handle *trans, struct btrfs_pending_snapshot *pending); + +/* scrub.c */ +int btrfs_scrub_dev(struct btrfs_root *root, u64 devid, u64 start, u64 end, + struct btrfs_scrub_progress *progress); +int btrfs_scrub_pause(struct btrfs_root *root); +int btrfs_scrub_pause_super(struct btrfs_root *root); +int btrfs_scrub_continue(struct btrfs_root *root); +int btrfs_scrub_continue_super(struct btrfs_root *root); +int btrfs_scrub_cancel(struct btrfs_root *root); +int btrfs_scrub_cancel_dev(struct btrfs_root *root, struct btrfs_device *dev); +int btrfs_scrub_cancel_devid(struct btrfs_root *root, u64 devid); +int btrfs_scrub_progress(struct btrfs_root *root, u64 devid, + struct btrfs_scrub_progress *progress); + #endif diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index fe5aec9b392..e48e8095c61 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1773,6 +1773,17 @@ struct btrfs_root *open_ctree(struct super_block *sb, INIT_LIST_HEAD(&fs_info->ordered_extents); spin_lock_init(&fs_info->ordered_extent_lock); + mutex_init(&fs_info->scrub_lock); + atomic_set(&fs_info->scrubs_running, 0); + atomic_set(&fs_info->scrub_pause_req, 0); + atomic_set(&fs_info->scrubs_paused, 0); + atomic_set(&fs_info->scrub_cancel_req, 0); + init_waitqueue_head(&fs_info->scrub_pause_wait); + init_rwsem(&fs_info->scrub_super_lock); + fs_info->scrub_workers_refcnt = 0; + btrfs_init_workers(&fs_info->scrub_workers, "scrub", + fs_info->thread_pool_size, &fs_info->generic_worker); + sb->s_blocksize = 4096; sb->s_blocksize_bits = blksize_bits(4096); sb->s_bdi = &fs_info->bdi; @@ -2599,6 +2610,7 @@ int close_ctree(struct btrfs_root *root) fs_info->closing = 1; smp_mb(); + btrfs_scrub_cancel(root); btrfs_put_block_group_cache(fs_info); /* diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c index a6a9d4e8b49..39ca7c1250e 100644 --- a/fs/btrfs/file-item.c +++ b/fs/btrfs/file-item.c @@ -266,7 +266,7 @@ int btrfs_lookup_bio_sums_dio(struct btrfs_root *root, struct inode *inode, } int btrfs_lookup_csums_range(struct btrfs_root *root, u64 start, u64 end, - struct list_head *list) + struct list_head *list, int search_commit) { struct btrfs_key key; struct btrfs_path *path; @@ -283,6 +283,12 @@ int btrfs_lookup_csums_range(struct btrfs_root *root, u64 start, u64 end, path = btrfs_alloc_path(); BUG_ON(!path); + if (search_commit) { + path->skip_locking = 1; + path->reada = 2; + path->search_commit_root = 1; + } + key.objectid = BTRFS_EXTENT_CSUM_OBJECTID; key.offset = start; key.type = BTRFS_EXTENT_CSUM_KEY; diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 870869aab0b..27142446b30 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -1007,7 +1007,7 @@ static noinline int csum_exist_in_range(struct btrfs_root *root, LIST_HEAD(list); ret = btrfs_lookup_csums_range(root->fs_info->csum_root, bytenr, - bytenr + num_bytes - 1, &list); + bytenr + num_bytes - 1, &list, 0); if (ret == 0 && list_empty(&list)) return 0; diff --git a/fs/btrfs/ioctl.h b/fs/btrfs/ioctl.h index 8fb382167b1..37ac030d64b 100644 --- a/fs/btrfs/ioctl.h +++ b/fs/btrfs/ioctl.h @@ -42,6 +42,43 @@ struct btrfs_ioctl_vol_args_v2 { char name[BTRFS_SUBVOL_NAME_MAX + 1]; }; +/* + * structure to report errors and progress to userspace, either as a + * result of a finished scrub, a canceled scrub or a progress inquiry + */ +struct btrfs_scrub_progress { + __u64 data_extents_scrubbed; /* # of data extents scrubbed */ + __u64 tree_extents_scrubbed; /* # of tree extents scrubbed */ + __u64 data_bytes_scrubbed; /* # of data bytes scrubbed */ + __u64 tree_bytes_scrubbed; /* # of tree bytes scrubbed */ + __u64 read_errors; /* # of read errors encountered (EIO) */ + __u64 csum_errors; /* # of failed csum checks */ + __u64 verify_errors; /* # of occurences, where the metadata + * of a tree block did not match the + * expected values, like generation or + * logical */ + __u64 no_csum; /* # of 4k data block for which no csum + * is present, probably the result of + * data written with nodatasum */ + __u64 csum_discards; /* # of csum for which no data was found + * in the extent tree. */ + __u64 super_errors; /* # of bad super blocks encountered */ + __u64 malloc_errors; /* # of internal kmalloc errors. These + * will likely cause an incomplete + * scrub */ + __u64 uncorrectable_errors; /* # of errors where either no intact + * copy was found or the writeback + * failed */ + __u64 corrected_errors; /* # of errors corrected */ + __u64 last_physical; /* last physical address scrubbed. In + * case a scrub was aborted, this can + * be used to restart the scrub */ + __u64 unverified_errors; /* # of occurences where a read for a + * full (64k) bio failed, but the re- + * check succeeded for each 4k piece. + * Intermittent error. */ +}; + #define BTRFS_INO_LOOKUP_PATH_MAX 4080 struct btrfs_ioctl_ino_lookup_args { __u64 treeid; diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c index 58250e09eb0..db1dffa9952 100644 --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -4242,7 +4242,7 @@ int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len) disk_bytenr = file_pos + BTRFS_I(inode)->index_cnt; ret = btrfs_lookup_csums_range(root->fs_info->csum_root, disk_bytenr, - disk_bytenr + len - 1, &list); + disk_bytenr + len - 1, &list, 0); while (!list_empty(&list)) { sums = list_entry(list.next, struct btrfs_ordered_sum, list); diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c new file mode 100644 index 00000000000..70f9fa772ee --- /dev/null +++ b/fs/btrfs/scrub.c @@ -0,0 +1,1492 @@ +/* + * Copyright (C) 2011 STRATO. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License v2 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; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + */ + +#include <linux/sched.h> +#include <linux/pagemap.h> +#include <linux/writeback.h> +#include <linux/blkdev.h> +#include <linux/rbtree.h> +#include <linux/slab.h> +#include <linux/workqueue.h> +#include "ctree.h" +#include "volumes.h" +#include "disk-io.h" +#include "ordered-data.h" + +/* + * This is only the first step towards a full-features scrub. It reads all + * extent and super block and verifies the checksums. In case a bad checksum + * is found or the extent cannot be read, good data will be written back if + * any can be found. + * + * Future enhancements: + * - To enhance the performance, better read-ahead strategies for the + * extent-tree can be employed. + * - In case an unrepairable extent is encountered, track which files are + * affected and report them + * - In case of a read error on files with nodatasum, map the file and read + * the extent to trigger a writeback of the good copy + * - track and record media errors, throw out bad devices + * - add a readonly mode + * - add a mode to also read unallocated space + * - make the prefetch cancellable + */ + +struct scrub_bio; +struct scrub_page; +struct scrub_dev; +struct scrub_fixup; +static void scrub_bio_end_io(struct bio *bio, int err); +static void scrub_checksum(struct btrfs_work *work); +static int scrub_checksum_data(struct scrub_dev *sdev, + struct scrub_page *spag, void *buffer); +static int scrub_checksum_tree_block(struct scrub_dev *sdev, + struct scrub_page *spag, u64 logical, + void *buffer); +static int scrub_checksum_super(struct scrub_bio *sbio, void *buffer); +static void scrub_recheck_end_io(struct bio *bio, int err); +static void scrub_fixup_worker(struct btrfs_work *work); +static void scrub_fixup(struct scrub_fixup *fixup); + +#define SCRUB_PAGES_PER_BIO 16 /* 64k per bio */ +#define SCRUB_BIOS_PER_DEV 16 /* 1 MB per device in flight */ + +struct scrub_page { + u64 flags; /* extent flags */ + u64 generation; + u64 mirror_num; + int have_csum; + u8 csum[BTRFS_CSUM_SIZE]; +}; + +struct scrub_bio { + int index; + struct scrub_dev *sdev; + struct bio *bio; + int err; + u64 logical; + u64 physical; + struct scrub_page spag[SCRUB_PAGES_PER_BIO]; + u64 count; + int next_free; + struct btrfs_work work; +}; + +struct scrub_dev { + struct scrub_bio *bios[SCRUB_BIOS_PER_DEV]; + struct btrfs_device *dev; + int first_free; + int curr; + atomic_t in_flight; + spinlock_t list_lock; + wait_queue_head_t list_wait; + u16 csum_size; + struct list_head csum_list; + atomic_t cancel_req; + /* + * statistics + */ + struct btrfs_scrub_progress stat; + spinlock_t stat_lock; +}; + +struct scrub_fixup { + struct scrub_dev *sdev; + struct bio *bio; + u64 logical; + u64 physical; + struct scrub_page spag; + struct btrfs_work work; + int err; + int recheck; +}; + +static void scrub_free_csums(struct scrub_dev *sdev) +{ + while (!list_empty(&sdev->csum_list)) { + struct btrfs_ordered_sum *sum; + sum = list_first_entry(&sdev->csum_list, + struct btrfs_ordered_sum, list); + list_del(&sum->list); + kfree(sum); + } +} + +static noinline_for_stack void scrub_free_dev(struct scrub_dev *sdev) +{ + int i; + int j; + struct page *last_page; + + if (!sdev) + return; + + for (i = 0; i < SCRUB_BIOS_PER_DEV; ++i) { + struct scrub_bio *sbio = sdev->bios[i]; + struct bio *bio; + + if (!sbio) + break; + + bio = sbio->bio; + if (bio) { + last_page = NULL; + for (j = 0; j < bio->bi_vcnt; ++j) { + if (bio->bi_io_vec[j].bv_page == last_page) + continue; + last_page = bio->bi_io_vec[j].bv_page; + __free_page(last_page); + } + bio_put(bio); + } + kfree(sbio); + } + + scrub_free_csums(sdev); + kfree(sdev); +} + +static noinline_for_stack +struct scrub_dev *scrub_setup_dev(struct btrfs_device *dev) +{ + struct scrub_dev *sdev; + int i; + int j; + int ret; + struct btrfs_fs_info *fs_info = dev->dev_root->fs_info; + + sdev = kzalloc(sizeof(*sdev), GFP_NOFS); + if (!sdev) + goto nomem; + sdev->dev = dev; + for (i = 0; i < SCRUB_BIOS_PER_DEV; ++i) { + struct bio *bio; + struct scrub_bio *sbio; + + sbio = kzalloc(sizeof(*sbio), GFP_NOFS); + if (!sbio) + goto nomem; + sdev->bios[i] = sbio; + + bio = bio_kmalloc(GFP_NOFS, SCRUB_PAGES_PER_BIO); + if (!bio) + goto nomem; + + sbio->index = i; + sbio->sdev = sdev; + sbio->bio = bio; + sbio->count = 0; + sbio->work.func = scrub_checksum; + bio->bi_private = sdev->bios[i]; + bio->bi_end_io = scrub_bio_end_io; + bio->bi_sector = 0; + bio->bi_bdev = dev->bdev; + bio->bi_size = 0; + + for (j = 0; j < SCRUB_PAGES_PER_BIO; ++j) { + struct page *page; + page = alloc_page(GFP_NOFS); + if (!page) + goto nomem; + + ret = bio_add_page(bio, page, PAGE_SIZE, 0); + if (!ret) + goto nomem; + } + WARN_ON(bio->bi_vcnt != SCRUB_PAGES_PER_BIO); + + if (i != SCRUB_BIOS_PER_DEV-1) + sdev->bios[i]->next_free = i + 1; + else + sdev->bios[i]->next_free = -1; + } + sdev->first_free = 0; + sdev->curr = -1; + atomic_set(&sdev->in_flight, 0); + atomic_set(&sdev->cancel_req, 0); + sdev->csum_size = btrfs_super_csum_size(&fs_info->super_copy); + INIT_LIST_HEAD(&sdev->csum_list); + + spin_lock_init(&sdev->list_lock); + spin_lock_init(&sdev->stat_lock); + init_waitqueue_head(&sdev->list_wait); + return sdev; + +nomem: + scrub_free_dev(sdev); + return ERR_PTR(-ENOMEM); +} + +/* + * scrub_recheck_error gets called when either verification of the page + * failed or the bio failed to read, e.g. with EIO. In the latter case, + * recheck_error gets called for every page in the bio, even though only + * one may be bad + */ +static void scrub_recheck_error(struct scrub_bio *sbio, int ix) +{ + struct scrub_dev *sdev = sbio->sdev; + struct btrfs_fs_info *fs_info = sdev->dev->dev_root->fs_info; + struct bio *bio = NULL; + struct page *page = NULL; + struct scrub_fixup *fixup = NULL; + int ret; + + /* + * while we're in here we do not want the transaction to commit. + * To prevent it, we increment scrubs_running. scrub_pause will + * have to wait until we're finished + * we can safely increment scrubs_running here, because we're + * in the context of the original bio which is still marked in_flight + */ + atomic_inc(&fs_info->scrubs_running); + + fixup = kzalloc(sizeof(*fixup), GFP_NOFS); + if (!fixup) + goto malloc_error; + + fixup->logical = sbio->logical + ix * PAGE_SIZE; + fixup->physical = sbio->physical + ix * PAGE_SIZE; + fixup->spag = sbio->spag[ix]; + fixup->sdev = sdev; + + bio = bio_alloc(GFP_NOFS, 1); + if (!bio) + goto malloc_error; + bio->bi_private = fixup; + bio->bi_size = 0; + bio->bi_bdev = sdev->dev->bdev; + fixup->bio = bio; + fixup->recheck = 0; + + page = alloc_page(GFP_NOFS); + if (!page) + goto malloc_error; + + ret = bio_add_page(bio, page, PAGE_SIZE, 0); + if (!ret) + goto malloc_error; + + if (!sbio->err) { + /* + * shorter path: just a checksum error, go ahead and correct it + */ + scrub_fixup_worker(&fixup->work); + return; + } + + /* + * an I/O-error occured for one of the blocks in the bio, not + * necessarily for this one, so first try to read it separately + */ + fixup->work.func = scrub_fixup_worker; + fixup->recheck = 1; + bio->bi_end_io = scrub_recheck_end_io; + bio->bi_sector = fixup->physical >> 9; + bio->bi_bdev = sdev->dev->bdev; + submit_bio(0, bio); + + return; + +malloc_error: + if (bio) + bio_put(bio); + if (page) + __free_page(page); + kfree(fixup); + spin_lock(&sdev->stat_lock); + ++sdev->stat.malloc_errors; + spin_unlock(&sdev->stat_lock); + atomic_dec(&fs_info->scrubs_running); + wake_up(&fs_info->scrub_pause_wait); +} + +static void scrub_recheck_end_io(struct bio *bio, int err) +{ + struct scrub_fixup *fixup = bio->bi_private; + struct btrfs_fs_info *fs_info = fixup->sdev->dev->dev_root->fs_info; + + fixup->err = err; + btrfs_queue_worker(&fs_info->scrub_workers, &fixup->work); +} + +static int scrub_fixup_check(struct scrub_fixup *fixup) +{ + int ret = 1; + struct page *page; + void *buffer; + u64 flags = fixup->spag.flags; + + page = fixup->bio->bi_io_vec[0].bv_page; + buffer = kmap_atomic(page, KM_USER0); + if (flags & BTRFS_EXTENT_FLAG_DATA) { + ret = scrub_checksum_data(fixup->sdev, + &fixup->spag, buffer); + } else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { + ret = scrub_checksum_tree_block(fixup->sdev, + &fixup->spag, + fixup->logical, + buffer); + } else { + WARN_ON(1); + } + kunmap_atomic(buffer, KM_USER0); + + return ret; +} + +static void scrub_fixup_worker(struct btrfs_work *work) +{ + struct scrub_fixup *fixup; + struct btrfs_fs_info *fs_info; + u64 flags; + int ret = 1; + + fixup = container_of(work, struct scrub_fixup, work); + fs_info = fixup->sdev->dev->dev_root->fs_info; + flags = fixup->spag.flags; + + if (fixup->recheck && fixup->err == 0) + ret = scrub_fixup_check(fixup); + + if (ret || fixup->err) + scrub_fixup(fixup); + + __free_page(fixup->bio->bi_io_vec[0].bv_page); + bio_put(fixup->bio); + + atomic_dec(&fs_info->scrubs_running); + wake_up(&fs_info->scrub_pause_wait); + + kfree(fixup); +} + +static void scrub_fixup_end_io(struct bio *bio, int err) +{ + complete((struct completion *)bio->bi_private); +} + +static void scrub_fixup(struct scrub_fixup *fixup) +{ + struct scrub_dev *sdev = fixup->sdev; + struct btrfs_fs_info *fs_info = sdev->dev->dev_root->fs_info; + struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; + struct btrfs_multi_bio *multi = NULL; + struct bio *bio = fixup->bio; + u64 length; + int i; + int ret; + DECLARE_COMPLETION_ONSTACK(complete); + + if ((fixup->spag.flags & BTRFS_EXTENT_FLAG_DATA) && + (fixup->spag.have_csum == 0)) { + /* + * nodatasum, don't try to fix anything + * FIXME: we can do better, open the inode and trigger a + * writeback + */ + goto uncorrectable; + } + + length = PAGE_SIZE; + ret = btrfs_map_block(map_tree, REQ_WRITE, fixup->logical, &length, + &multi, 0); + if (ret || !multi || length < PAGE_SIZE) { + printk(KERN_ERR + "scrub_fixup: btrfs_map_block failed us for %llu\n", + (unsigned long long)fixup->logical); + WARN_ON(1); + return; + } + + if (multi->num_stripes == 1) { + /* there aren't any replicas */ + goto uncorrectable; + } + + /* + * first find a good copy + */ + for (i = 0; i < multi->num_stripes; ++i) { + if (i == fixup->spag.mirror_num) + continue; + + bio->bi_sector = multi->stripes[i].physical >> 9; + bio->bi_bdev = multi->stripes[i].dev->bdev; + bio->bi_size = PAGE_SIZE; + bio->bi_next = NULL; + bio->bi_flags |= 1 << BIO_UPTODATE; + bio->bi_comp_cpu = -1; + bio->bi_end_io = scrub_fixup_end_io; + bio->bi_private = &complete; + + submit_bio(0, bio); + + wait_for_completion(&complete); + + if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) + /* I/O-error, this is not a good copy */ + continue; + + ret = scrub_fixup_check(fixup); + if (ret == 0) + break; + } + if (i == multi->num_stripes) + goto uncorrectable; + + /* + * the bio now contains good data, write it back + */ + bio->bi_sector = fixup->physical >> 9; + bio->bi_bdev = sdev->dev->bdev; + bio->bi_size = PAGE_SIZE; + bio->bi_next = NULL; + bio->bi_flags |= 1 << BIO_UPTODATE; + bio->bi_comp_cpu = -1; + bio->bi_end_io = scrub_fixup_end_io; + bio->bi_private = &complete; + + submit_bio(REQ_WRITE, bio); + + wait_for_completion(&complete); + + if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) + /* I/O-error, writeback failed, give up */ + goto uncorrectable; + + kfree(multi); + spin_lock(&sdev->stat_lock); + ++sdev->stat.corrected_errors; + spin_unlock(&sdev->stat_lock); + + if (printk_ratelimit()) + printk(KERN_ERR "btrfs: fixed up at %llu\n", + (unsigned long long)fixup->logical); + return; + +uncorrectable: + kfree(multi); + spin_lock(&sdev->stat_lock); + ++sdev->stat.uncorrectable_errors; + spin_unlock(&sdev->stat_lock); + + if (printk_ratelimit()) + printk(KERN_ERR "btrfs: unable to fixup at %llu\n", + (unsigned long long)fixup->logical); +} + +static void scrub_bio_end_io(struct bio *bio, int err) +{ + struct scrub_bio *sbio = bio->bi_private; + struct scrub_dev *sdev = sbio->sdev; + struct btrfs_fs_info *fs_info = sdev->dev->dev_root->fs_info; + + sbio->err = err; + + btrfs_queue_worker(&fs_info->scrub_workers, &sbio->work); +} + +static void scrub_checksum(struct btrfs_work *work) +{ + struct scrub_bio *sbio = container_of(work, struct scrub_bio, work); + struct scrub_dev *sdev = sbio->sdev; + struct page *page; + void *buffer; + int i; + u64 flags; + u64 logical; + int ret; + + if (sbio->err) { + struct bio *bio; + struct bio *old_bio; + + for (i = 0; i < sbio->count; ++i) + scrub_recheck_error(sbio, i); + spin_lock(&sdev->stat_lock); + ++sdev->stat.read_errors; + spin_unlock(&sdev->stat_lock); + + /* + * FIXME: allocate a new bio after a media error. I haven't + * figured out how to reuse this one + */ + old_bio = sbio->bio; + bio = bio_kmalloc(GFP_NOFS, SCRUB_PAGES_PER_BIO); + if (!bio) { + /* + * alloc failed. cancel the scrub and don't requeue + * this sbio + */ + printk(KERN_ERR "btrfs scrub: allocation failure, " + "cancelling scrub\n"); + atomic_inc(&sdev->dev->dev_root->fs_info-> + scrub_cancel_req); + goto out_no_enqueue; + } + sbio->bio = bio; + bio->bi_private = sbio; + bio->bi_end_io = scrub_bio_end_io; + bio->bi_sector = 0; + bio->bi_bdev = sbio->sdev->dev->bdev; + bio->bi_size = 0; + for (i = 0; i < SCRUB_PAGES_PER_BIO; ++i) { + struct page *page; + page = old_bio->bi_io_vec[i].bv_page; + bio_add_page(bio, page, PAGE_SIZE, 0); + } + bio_put(old_bio); + goto out; + } + for (i = 0; i < sbio->count; ++i) { + page = sbio->bio->bi_io_vec[i].bv_page; + buffer = kmap_atomic(page, KM_USER0); + flags = sbio->spag[i].flags; + logical = sbio->logical + i * PAGE_SIZE; + ret = 0; + if (flags & BTRFS_EXTENT_FLAG_DATA) { + ret = scrub_checksum_data(sdev, sbio->spag + i, buffer); + } else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { + ret = scrub_checksum_tree_block(sdev, sbio->spag + i, + logical, buffer); + } else if (flags & BTRFS_EXTENT_FLAG_SUPER) { + BUG_ON(i); + (void)scrub_checksum_super(sbio, buffer); + } else { + WARN_ON(1); + } + kunmap_atomic(buffer, KM_USER0); + if (ret) + scrub_recheck_error(sbio, i); + } + +out: + spin_lock(&sdev->list_lock); + sbio->next_free = sdev->first_free; + sdev->first_free = sbio->index; + spin_unlock(&sdev->list_lock); +out_no_enqueue: + atomic_dec(&sdev->in_flight); + wake_up(&sdev->list_wait); +} + +static int scrub_checksum_data(struct scrub_dev *sdev, + struct scrub_page *spag, void *buffer) +{ + u8 csum[BTRFS_CSUM_SIZE]; + u32 crc = ~(u32)0; + int fail = 0; + struct btrfs_root *root = sdev->dev->dev_root; + + if (!spag->have_csum) + return 0; + + crc = btrfs_csum_data(root, buffer, crc, PAGE_SIZE); + btrfs_csum_final(crc, csum); + if (memcmp(csum, spag->csum, sdev->csum_size)) + fail = 1; + + spin_lock(&sdev->stat_lock); + ++sdev->stat.data_extents_scrubbed; + sdev->stat.data_bytes_scrubbed += PAGE_SIZE; + if (fail) + ++sdev->stat.csum_errors; + spin_unlock(&sdev->stat_lock); + + return fail; +} + +static int scrub_checksum_tree_block(struct scrub_dev *sdev, + struct scrub_page *spag, u64 logical, + void *buffer) +{ + struct btrfs_header *h; + struct btrfs_root *root = sdev->dev->dev_root; + struct btrfs_fs_info *fs_info = root->fs_info; + u8 csum[BTRFS_CSUM_SIZE]; + u32 crc = ~(u32)0; + int fail = 0; + int crc_fail = 0; + + /* + * we don't use the getter functions here, as we + * a) don't have an extent buffer and + * b) the page is already kmapped + */ + h = (struct btrfs_header *)buffer; + + if (logical != le64_to_cpu(h->bytenr)) + ++fail; + + if (spag->generation != le64_to_cpu(h->generation)) + ++fail; + + if (memcmp(h->fsid, fs_info->fsid, BTRFS_UUID_SIZE)) + ++fail; + + if (memcmp(h->chunk_tree_uuid, fs_info->chunk_tree_uuid, + BTRFS_UUID_SIZE)) + ++fail; + + crc = btrfs_csum_data(root, buffer + BTRFS_CSUM_SIZE, crc, + PAGE_SIZE - BTRFS_CSUM_SIZE); + btrfs_csum_final(crc, csum); + if (memcmp(csum, h->csum, sdev->csum_size)) + ++crc_fail; + + spin_lock(&sdev->stat_lock); + ++sdev->stat.tree_extents_scrubbed; + sdev->stat.tree_bytes_scrubbed += PAGE_SIZE; + if (crc_fail) + ++sdev->stat.csum_errors; + if (fail) + ++sdev->stat.verify_errors; + spin_unlock(&sdev->stat_lock); + + return fail || crc_fail; +} + +static int scrub_checksum_super(struct scrub_bio *sbio, void *buffer) +{ + struct btrfs_super_block *s; + u64 logical; + struct scrub_dev *sdev = sbio->sdev; + struct btrfs_root *root = sdev->dev->dev_root; + struct btrfs_fs_info *fs_info = root->fs_info; + u8 csum[BTRFS_CSUM_SIZE]; + u32 crc = ~(u32)0; + int fail = 0; + + s = (struct btrfs_super_block *)buffer; + logical = sbio->logical; + + if (logical != le64_to_cpu(s->bytenr)) + ++fail; + + if (sbio->spag[0].generation != le64_to_cpu(s->generation)) + ++fail; + + if (memcmp(s->fsid, fs_info->fsid, BTRFS_UUID_SIZE)) + ++fail; + + crc = btrfs_csum_data(root, buffer + BTRFS_CSUM_SIZE, crc, + PAGE_SIZE - BTRFS_CSUM_SIZE); + btrfs_csum_final(crc, csum); + if (memcmp(csum, s->csum, sbio->sdev->csum_size)) + ++fail; + + if (fail) { + /* + * if we find an error in a super block, we just report it. + * They will get written with the next transaction commit + * anyway + */ + spin_lock(&sdev->stat_lock); + ++sdev->stat.super_errors; + spin_unlock(&sdev->stat_lock); + } + + return fail; +} + +static int scrub_submit(struct scrub_dev *sdev) +{ + struct scrub_bio *sbio; + + if (sdev->curr == -1) + return 0; + + sbio = sdev->bios[sdev->curr]; + + sbio->bio->bi_sector = sbio->physical >> 9; + sbio->bio->bi_size = sbio->count * PAGE_SIZE; + sbio->bio->bi_next = NULL; + sbio->bio->bi_flags |= 1 << BIO_UPTODATE; + sbio->bio->bi_comp_cpu = -1; + sbio->bio->bi_bdev = sdev->dev->bdev; + sbio->err = 0; + sdev->curr = -1; + atomic_inc(&sdev->in_flight); + + submit_bio(0, sbio->bio); + + return 0; +} + +static int scrub_page(struct scrub_dev *sdev, u64 logical, u64 len, + u64 physical, u64 flags, u64 gen, u64 mirror_num, + u8 *csum, int force) +{ + struct scrub_bio *sbio; + +again: + /* + * grab a fresh bio or wait for one to become available + */ + while (sdev->curr == -1) { + spin_lock(&sdev->list_lock); + sdev->curr = sdev->first_free; + if (sdev->curr != -1) { + sdev->first_free = sdev->bios[sdev->curr]->next_free; + sdev->bios[sdev->curr]->next_free = -1; + sdev->bios[sdev->curr]->count = 0; + spin_unlock(&sdev->list_lock); + } else { + spin_unlock(&sdev->list_lock); + wait_event(sdev->list_wait, sdev->first_free != -1); + } + } + sbio = sdev->bios[sdev->curr]; + if (sbio->count == 0) { + sbio->physical = physical; + sbio->logical = logical; + } else if (sbio->physical + sbio->count * PAGE_SIZE != physical) { + scrub_submit(sdev); + goto again; + } + sbio->spag[sbio->count].flags = flags; + sbio->spag[sbio->count].generation = gen; + sbio->spag[sbio->count].have_csum = 0; + sbio->spag[sbio->count].mirror_num = mirror_num; + if (csum) { + sbio->spag[sbio->count].have_csum = 1; + memcpy(sbio->spag[sbio->count].csum, csum, sdev->csum_size); + } + ++sbio->count; + if (sbio->count == SCRUB_PAGES_PER_BIO || force) + scrub_submit(sdev); + + return 0; +} + +static int scrub_find_csum(struct scrub_dev *sdev, u64 logical, u64 len, + u8 *csum) +{ + struct btrfs_ordered_sum *sum = NULL; + int ret = 0; + unsigned long i; + unsigned long num_sectors; + u32 sectorsize = sdev->dev->dev_root->sectorsize; + + while (!list_empty(&sdev->csum_list)) { + sum = list_first_entry(&sdev->csum_list, + struct btrfs_ordered_sum, list); + if (sum->bytenr > logical) + return 0; + if (sum->bytenr + sum->len > logical) + break; + + ++sdev->stat.csum_discards; + list_del(&sum->list); + kfree(sum); + sum = NULL; + } + if (!sum) + return 0; + + num_sectors = sum->len / sectorsize; + for (i = 0; i < num_sectors; ++i) { + if (sum->sums[i].bytenr == logical) { + memcpy(csum, &sum->sums[i].sum, sdev->csum_size); + ret = 1; + break; + } + } + if (ret && i == num_sectors - 1) { + list_del(&sum->list); + kfree(sum); + } + return ret; +} + +/* scrub extent tries to collect up to 64 kB for each bio */ +static int scrub_extent(struct scrub_dev *sdev, u64 logical, u64 len, + u64 physical, u64 flags, u64 gen, u64 mirror_num) +{ + int ret; + u8 csum[BTRFS_CSUM_SIZE]; + + while (len) { + u64 l = min_t(u64, len, PAGE_SIZE); + int have_csum = 0; + + if (flags & BTRFS_EXTENT_FLAG_DATA) { + /* push csums to sbio */ + have_csum = scrub_find_csum(sdev, logical, l, csum); + if (have_csum == 0) + ++sdev->stat.no_csum; + } + ret = scrub_page(sdev, logical, l, physical, flags, gen, + mirror_num, have_csum ? csum : NULL, 0); + if (ret) + return ret; + len -= l; + logical += l; + physical += l; + } + return 0; +} + +static noinline_for_stack int scrub_stripe(struct scrub_dev *sdev, + struct map_lookup *map, int num, u64 base, u64 length) |