diff options
Diffstat (limited to 'drivers/staging/zram')
| -rw-r--r-- | drivers/staging/zram/Kconfig | 25 | ||||
| -rw-r--r-- | drivers/staging/zram/Makefile | 3 | ||||
| -rw-r--r-- | drivers/staging/zram/zram.txt | 77 | ||||
| -rw-r--r-- | drivers/staging/zram/zram_drv.c | 921 | ||||
| -rw-r--r-- | drivers/staging/zram/zram_drv.h | 115 |
5 files changed, 0 insertions, 1141 deletions
diff --git a/drivers/staging/zram/Kconfig b/drivers/staging/zram/Kconfig deleted file mode 100644 index 983314c4134..00000000000 --- a/drivers/staging/zram/Kconfig +++ /dev/null @@ -1,25 +0,0 @@ -config ZRAM - tristate "Compressed RAM block device support" - depends on BLOCK && SYSFS && ZSMALLOC - select LZO_COMPRESS - select LZO_DECOMPRESS - default n - help - Creates virtual block devices called /dev/zramX (X = 0, 1, ...). - Pages written to these disks are compressed and stored in memory - itself. These disks allow very fast I/O and compression provides - good amounts of memory savings. - - It has several use cases, for example: /tmp storage, use as swap - disks and maybe many more. - - See zram.txt for more information. - Project home: <https://compcache.googlecode.com/> - -config ZRAM_DEBUG - bool "Compressed RAM block device debug support" - depends on ZRAM - default n - help - This option adds additional debugging code to the compressed - RAM block device driver. diff --git a/drivers/staging/zram/Makefile b/drivers/staging/zram/Makefile deleted file mode 100644 index cb0f9ced6a9..00000000000 --- a/drivers/staging/zram/Makefile +++ /dev/null @@ -1,3 +0,0 @@ -zram-y := zram_drv.o - -obj-$(CONFIG_ZRAM) += zram.o diff --git a/drivers/staging/zram/zram.txt b/drivers/staging/zram/zram.txt deleted file mode 100644 index 765d790ae83..00000000000 --- a/drivers/staging/zram/zram.txt +++ /dev/null @@ -1,77 +0,0 @@ -zram: Compressed RAM based block devices ----------------------------------------- - -Project home: http://compcache.googlecode.com/ - -* Introduction - -The zram module creates RAM based block devices named /dev/zram<id> -(<id> = 0, 1, ...). Pages written to these disks are compressed and stored -in memory itself. These disks allow very fast I/O and compression provides -good amounts of memory savings. Some of the usecases include /tmp storage, -use as swap disks, various caches under /var and maybe many more :) - -Statistics for individual zram devices are exported through sysfs nodes at -/sys/block/zram<id>/ - -* Usage - -Following shows a typical sequence of steps for using zram. - -1) Load Module: - modprobe zram num_devices=4 - This creates 4 devices: /dev/zram{0,1,2,3} - (num_devices parameter is optional. Default: 1) - -2) Set Disksize - Set disk size by writing the value to sysfs node 'disksize'. - The value can be either in bytes or you can use mem suffixes. - Examples: - # Initialize /dev/zram0 with 50MB disksize - echo $((50*1024*1024)) > /sys/block/zram0/disksize - - # Using mem suffixes - echo 256K > /sys/block/zram0/disksize - echo 512M > /sys/block/zram0/disksize - echo 1G > /sys/block/zram0/disksize - -3) Activate: - mkswap /dev/zram0 - swapon /dev/zram0 - - mkfs.ext4 /dev/zram1 - mount /dev/zram1 /tmp - -4) Stats: - Per-device statistics are exported as various nodes under - /sys/block/zram<id>/ - disksize - num_reads - num_writes - invalid_io - notify_free - discard - zero_pages - orig_data_size - compr_data_size - mem_used_total - -5) Deactivate: - swapoff /dev/zram0 - umount /dev/zram1 - -6) Reset: - Write any positive value to 'reset' sysfs node - echo 1 > /sys/block/zram0/reset - echo 1 > /sys/block/zram1/reset - - This frees all the memory allocated for the given device and - resets the disksize to zero. You must set the disksize again - before reusing the device. - -Please report any problems at: - - Mailing list: linux-mm-cc at laptop dot org - - Issue tracker: http://code.google.com/p/compcache/issues/list - -Nitin Gupta -ngupta@vflare.org diff --git a/drivers/staging/zram/zram_drv.c b/drivers/staging/zram/zram_drv.c deleted file mode 100644 index 82c7202fd5c..00000000000 --- a/drivers/staging/zram/zram_drv.c +++ /dev/null @@ -1,921 +0,0 @@ -/* - * Compressed RAM block device - * - * Copyright (C) 2008, 2009, 2010 Nitin Gupta - * - * This code is released using a dual license strategy: BSD/GPL - * You can choose the licence that better fits your requirements. - * - * Released under the terms of 3-clause BSD License - * Released under the terms of GNU General Public License Version 2.0 - * - * Project home: http://compcache.googlecode.com - */ - -#define KMSG_COMPONENT "zram" -#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt - -#ifdef CONFIG_ZRAM_DEBUG -#define DEBUG -#endif - -#include <linux/module.h> -#include <linux/kernel.h> -#include <linux/bio.h> -#include <linux/bitops.h> -#include <linux/blkdev.h> -#include <linux/buffer_head.h> -#include <linux/device.h> -#include <linux/genhd.h> -#include <linux/highmem.h> -#include <linux/slab.h> -#include <linux/lzo.h> -#include <linux/string.h> -#include <linux/vmalloc.h> - -#include "zram_drv.h" - -/* Globals */ -static int zram_major; -static struct zram *zram_devices; - -/* Module params (documentation at end) */ -static unsigned int num_devices = 1; - -static inline struct zram *dev_to_zram(struct device *dev) -{ - return (struct zram *)dev_to_disk(dev)->private_data; -} - -static ssize_t disksize_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct zram *zram = dev_to_zram(dev); - - return sprintf(buf, "%llu\n", zram->disksize); -} - -static ssize_t initstate_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct zram *zram = dev_to_zram(dev); - - return sprintf(buf, "%u\n", zram->init_done); -} - -static ssize_t num_reads_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct zram *zram = dev_to_zram(dev); - - return sprintf(buf, "%llu\n", - (u64)atomic64_read(&zram->stats.num_reads)); -} - -static ssize_t num_writes_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct zram *zram = dev_to_zram(dev); - - return sprintf(buf, "%llu\n", - (u64)atomic64_read(&zram->stats.num_writes)); -} - -static ssize_t invalid_io_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct zram *zram = dev_to_zram(dev); - - return sprintf(buf, "%llu\n", - (u64)atomic64_read(&zram->stats.invalid_io)); -} - -static ssize_t notify_free_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct zram *zram = dev_to_zram(dev); - - return sprintf(buf, "%llu\n", - (u64)atomic64_read(&zram->stats.notify_free)); -} - -static ssize_t zero_pages_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct zram *zram = dev_to_zram(dev); - - return sprintf(buf, "%u\n", zram->stats.pages_zero); -} - -static ssize_t orig_data_size_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct zram *zram = dev_to_zram(dev); - - return sprintf(buf, "%llu\n", - (u64)(zram->stats.pages_stored) << PAGE_SHIFT); -} - -static ssize_t compr_data_size_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct zram *zram = dev_to_zram(dev); - - return sprintf(buf, "%llu\n", - (u64)atomic64_read(&zram->stats.compr_size)); -} - -static ssize_t mem_used_total_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - u64 val = 0; - struct zram *zram = dev_to_zram(dev); - struct zram_meta *meta = zram->meta; - - down_read(&zram->init_lock); - if (zram->init_done) - val = zs_get_total_size_bytes(meta->mem_pool); - up_read(&zram->init_lock); - - return sprintf(buf, "%llu\n", val); -} - -static int zram_test_flag(struct zram_meta *meta, u32 index, - enum zram_pageflags flag) -{ - return meta->table[index].flags & BIT(flag); -} - -static void zram_set_flag(struct zram_meta *meta, u32 index, - enum zram_pageflags flag) -{ - meta->table[index].flags |= BIT(flag); -} - -static void zram_clear_flag(struct zram_meta *meta, u32 index, - enum zram_pageflags flag) -{ - meta->table[index].flags &= ~BIT(flag); -} - -static inline int is_partial_io(struct bio_vec *bvec) -{ - return bvec->bv_len != PAGE_SIZE; -} - -/* - * Check if request is within bounds and aligned on zram logical blocks. - */ -static inline int valid_io_request(struct zram *zram, struct bio *bio) -{ - u64 start, end, bound; - - /* unaligned request */ - if (unlikely(bio->bi_sector & (ZRAM_SECTOR_PER_LOGICAL_BLOCK - 1))) - return 0; - if (unlikely(bio->bi_size & (ZRAM_LOGICAL_BLOCK_SIZE - 1))) - return 0; - - start = bio->bi_sector; - end = start + (bio->bi_size >> SECTOR_SHIFT); - bound = zram->disksize >> SECTOR_SHIFT; - /* out of range range */ - if (unlikely(start >= bound || end > bound || start > end)) - return 0; - - /* I/O request is valid */ - return 1; -} - -static void zram_meta_free(struct zram_meta *meta) -{ - zs_destroy_pool(meta->mem_pool); - kfree(meta->compress_workmem); - free_pages((unsigned long)meta->compress_buffer, 1); - vfree(meta->table); - kfree(meta); -} - -static struct zram_meta *zram_meta_alloc(u64 disksize) -{ - size_t num_pages; - struct zram_meta *meta = kmalloc(sizeof(*meta), GFP_KERNEL); - if (!meta) - goto out; - - meta->compress_workmem = kzalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL); - if (!meta->compress_workmem) - goto free_meta; - - meta->compress_buffer = - (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 1); - if (!meta->compress_buffer) { - pr_err("Error allocating compressor buffer space\n"); - goto free_workmem; - } - - num_pages = disksize >> PAGE_SHIFT; - meta->table = vzalloc(num_pages * sizeof(*meta->table)); - if (!meta->table) { - pr_err("Error allocating zram address table\n"); - goto free_buffer; - } - - meta->mem_pool = zs_create_pool(GFP_NOIO | __GFP_HIGHMEM); - if (!meta->mem_pool) { - pr_err("Error creating memory pool\n"); - goto free_table; - } - - return meta; - -free_table: - vfree(meta->table); -free_buffer: - free_pages((unsigned long)meta->compress_buffer, 1); -free_workmem: - kfree(meta->compress_workmem); -free_meta: - kfree(meta); - meta = NULL; -out: - return meta; -} - -static void update_position(u32 *index, int *offset, struct bio_vec *bvec) -{ - if (*offset + bvec->bv_len >= PAGE_SIZE) - (*index)++; - *offset = (*offset + bvec->bv_len) % PAGE_SIZE; -} - -static int page_zero_filled(void *ptr) -{ - unsigned int pos; - unsigned long *page; - - page = (unsigned long *)ptr; - - for (pos = 0; pos != PAGE_SIZE / sizeof(*page); pos++) { - if (page[pos]) - return 0; - } - - return 1; -} - -static void handle_zero_page(struct bio_vec *bvec) -{ - struct page *page = bvec->bv_page; - void *user_mem; - - user_mem = kmap_atomic(page); - if (is_partial_io(bvec)) - memset(user_mem + bvec->bv_offset, 0, bvec->bv_len); - else - clear_page(user_mem); - kunmap_atomic(user_mem); - - flush_dcache_page(page); -} - -static void zram_free_page(struct zram *zram, size_t index) -{ - struct zram_meta *meta = zram->meta; - unsigned long handle = meta->table[index].handle; - u16 size = meta->table[index].size; - - if (unlikely(!handle)) { - /* - * No memory is allocated for zero filled pages. - * Simply clear zero page flag. - */ - if (zram_test_flag(meta, index, ZRAM_ZERO)) { - zram_clear_flag(meta, index, ZRAM_ZERO); - zram->stats.pages_zero--; - } - return; - } - - if (unlikely(size > max_zpage_size)) - zram->stats.bad_compress--; - - zs_free(meta->mem_pool, handle); - - if (size <= PAGE_SIZE / 2) - zram->stats.good_compress--; - - atomic64_sub(meta->table[index].size, &zram->stats.compr_size); - zram->stats.pages_stored--; - - meta->table[index].handle = 0; - meta->table[index].size = 0; -} - -static int zram_decompress_page(struct zram *zram, char *mem, u32 index) -{ - int ret = LZO_E_OK; - size_t clen = PAGE_SIZE; - unsigned char *cmem; - struct zram_meta *meta = zram->meta; - unsigned long handle = meta->table[index].handle; - - if (!handle || zram_test_flag(meta, index, ZRAM_ZERO)) { - clear_page(mem); - return 0; - } - - cmem = zs_map_object(meta->mem_pool, handle, ZS_MM_RO); - if (meta->table[index].size == PAGE_SIZE) - copy_page(mem, cmem); - else - ret = lzo1x_decompress_safe(cmem, meta->table[index].size, - mem, &clen); - zs_unmap_object(meta->mem_pool, handle); - - /* Should NEVER happen. Return bio error if it does. */ - if (unlikely(ret != LZO_E_OK)) { - pr_err("Decompression failed! err=%d, page=%u\n", ret, index); - atomic64_inc(&zram->stats.failed_reads); - return ret; - } - - return 0; -} - -static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec, - u32 index, int offset, struct bio *bio) -{ - int ret; - struct page *page; - unsigned char *user_mem, *uncmem = NULL; - struct zram_meta *meta = zram->meta; - page = bvec->bv_page; - - if (unlikely(!meta->table[index].handle) || - zram_test_flag(meta, index, ZRAM_ZERO)) { - handle_zero_page(bvec); - return 0; - } - - if (is_partial_io(bvec)) - /* Use a temporary buffer to decompress the page */ - uncmem = kmalloc(PAGE_SIZE, GFP_NOIO); - - user_mem = kmap_atomic(page); - if (!is_partial_io(bvec)) - uncmem = user_mem; - - if (!uncmem) { - pr_info("Unable to allocate temp memory\n"); - ret = -ENOMEM; - goto out_cleanup; - } - - ret = zram_decompress_page(zram, uncmem, index); - /* Should NEVER happen. Return bio error if it does. */ - if (unlikely(ret != LZO_E_OK)) - goto out_cleanup; - - if (is_partial_io(bvec)) - memcpy(user_mem + bvec->bv_offset, uncmem + offset, - bvec->bv_len); - - flush_dcache_page(page); - ret = 0; -out_cleanup: - kunmap_atomic(user_mem); - if (is_partial_io(bvec)) - kfree(uncmem); - return ret; -} - -static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index, - int offset) -{ - int ret = 0; - size_t clen; - unsigned long handle; - struct page *page; - unsigned char *user_mem, *cmem, *src, *uncmem = NULL; - struct zram_meta *meta = zram->meta; - - page = bvec->bv_page; - src = meta->compress_buffer; - - if (is_partial_io(bvec)) { - /* - * This is a partial IO. We need to read the full page - * before to write the changes. - */ - uncmem = kmalloc(PAGE_SIZE, GFP_NOIO); - if (!uncmem) { - ret = -ENOMEM; - goto out; - } - ret = zram_decompress_page(zram, uncmem, index); - if (ret) - goto out; - } - - /* - * System overwrites unused sectors. Free memory associated - * with this sector now. - */ - if (meta->table[index].handle || - zram_test_flag(meta, index, ZRAM_ZERO)) - zram_free_page(zram, index); - - user_mem = kmap_atomic(page); - - if (is_partial_io(bvec)) { - memcpy(uncmem + offset, user_mem + bvec->bv_offset, - bvec->bv_len); - kunmap_atomic(user_mem); - user_mem = NULL; - } else { - uncmem = user_mem; - } - - if (page_zero_filled(uncmem)) { - kunmap_atomic(user_mem); - zram->stats.pages_zero++; - zram_set_flag(meta, index, ZRAM_ZERO); - ret = 0; - goto out; - } - - ret = lzo1x_1_compress(uncmem, PAGE_SIZE, src, &clen, - meta->compress_workmem); - - if (!is_partial_io(bvec)) { - kunmap_atomic(user_mem); - user_mem = NULL; - uncmem = NULL; - } - - if (unlikely(ret != LZO_E_OK)) { - pr_err("Compression failed! err=%d\n", ret); - goto out; - } - - if (unlikely(clen > max_zpage_size)) { - zram->stats.bad_compress++; - clen = PAGE_SIZE; - src = NULL; - if (is_partial_io(bvec)) - src = uncmem; - } - - handle = zs_malloc(meta->mem_pool, clen); - if (!handle) { - pr_info("Error allocating memory for compressed page: %u, size=%zu\n", - index, clen); - ret = -ENOMEM; - goto out; - } - cmem = zs_map_object(meta->mem_pool, handle, ZS_MM_WO); - - if ((clen == PAGE_SIZE) && !is_partial_io(bvec)) { - src = kmap_atomic(page); - copy_page(cmem, src); - kunmap_atomic(src); - } else { - memcpy(cmem, src, clen); - } - - zs_unmap_object(meta->mem_pool, handle); - - meta->table[index].handle = handle; - meta->table[index].size = clen; - - /* Update stats */ - atomic64_add(clen, &zram->stats.compr_size); - zram->stats.pages_stored++; - if (clen <= PAGE_SIZE / 2) - zram->stats.good_compress++; - -out: - if (is_partial_io(bvec)) - kfree(uncmem); - - if (ret) - atomic64_inc(&zram->stats.failed_writes); - return ret; -} - -static int zram_bvec_rw(struct zram *zram, struct bio_vec *bvec, u32 index, - int offset, struct bio *bio, int rw) -{ - int ret; - - if (rw == READ) { - down_read(&zram->lock); - ret = zram_bvec_read(zram, bvec, index, offset, bio); - up_read(&zram->lock); - } else { - down_write(&zram->lock); - ret = zram_bvec_write(zram, bvec, index, offset); - up_write(&zram->lock); - } - - return ret; -} - -static void zram_reset_device(struct zram *zram) -{ - size_t index; - struct zram_meta *meta; - - if (!zram->init_done) - return; - - meta = zram->meta; - zram->init_done = 0; - - /* Free all pages that are still in this zram device */ - for (index = 0; index < zram->disksize >> PAGE_SHIFT; index++) { - unsigned long handle = meta->table[index].handle; - if (!handle) - continue; - - zs_free(meta->mem_pool, handle); - } - - zram_meta_free(zram->meta); - zram->meta = NULL; - /* Reset stats */ - memset(&zram->stats, 0, sizeof(zram->stats)); - - zram->disksize = 0; - set_capacity(zram->disk, 0); -} - -static void zram_init_device(struct zram *zram, struct zram_meta *meta) -{ - if (zram->disksize > 2 * (totalram_pages << PAGE_SHIFT)) { - pr_info( - "There is little point creating a zram of greater than " - "twice the size of memory since we expect a 2:1 compression " - "ratio. Note that zram uses about 0.1%% of the size of " - "the disk when not in use so a huge zram is " - "wasteful.\n" - "\tMemory Size: %lu kB\n" - "\tSize you selected: %llu kB\n" - "Continuing anyway ...\n", - (totalram_pages << PAGE_SHIFT) >> 10, zram->disksize >> 10 - ); - } - - /* zram devices sort of resembles non-rotational disks */ - queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zram->disk->queue); - - zram->meta = meta; - zram->init_done = 1; - - pr_debug("Initialization done!\n"); -} - -static ssize_t disksize_store(struct device *dev, - struct device_attribute *attr, const char *buf, size_t len) -{ - u64 disksize; - struct zram_meta *meta; - struct zram *zram = dev_to_zram(dev); - - disksize = memparse(buf, NULL); - if (!disksize) - return -EINVAL; - - disksize = PAGE_ALIGN(disksize); - meta = zram_meta_alloc(disksize); - down_write(&zram->init_lock); - if (zram->init_done) { - up_write(&zram->init_lock); - zram_meta_free(meta); - pr_info("Cannot change disksize for initialized device\n"); - return -EBUSY; - } - - zram->disksize = disksize; - set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT); - zram_init_device(zram, meta); - up_write(&zram->init_lock); - - return len; -} - -static ssize_t reset_store(struct device *dev, - struct device_attribute *attr, const char *buf, size_t len) -{ - int ret; - unsigned short do_reset; - struct zram *zram; - struct block_device *bdev; - - zram = dev_to_zram(dev); - bdev = bdget_disk(zram->disk, 0); - - /* Do not reset an active device! */ - if (bdev->bd_holders) - return -EBUSY; - - ret = kstrtou16(buf, 10, &do_reset); - if (ret) - return ret; - - if (!do_reset) - return -EINVAL; - - /* Make sure all pending I/O is finished */ - if (bdev) - fsync_bdev(bdev); - - zram_reset_device(zram); - return len; -} - -static void __zram_make_request(struct zram *zram, struct bio *bio, int rw) -{ - int i, offset; - u32 index; - struct bio_vec *bvec; - - switch (rw) { - case READ: - atomic64_inc(&zram->stats.num_reads); - break; - case WRITE: - atomic64_inc(&zram->stats.num_writes); - break; - } - - index = bio->bi_sector >> SECTORS_PER_PAGE_SHIFT; - offset = (bio->bi_sector & (SECTORS_PER_PAGE - 1)) << SECTOR_SHIFT; - - bio_for_each_segment(bvec, bio, i) { - int max_transfer_size = PAGE_SIZE - offset; - - if (bvec->bv_len > max_transfer_size) { - /* - * zram_bvec_rw() can only make operation on a single - * zram page. Split the bio vector. - */ - struct bio_vec bv; - - bv.bv_page = bvec->bv_page; - bv.bv_len = max_transfer_size; - bv.bv_offset = bvec->bv_offset; - - if (zram_bvec_rw(zram, &bv, index, offset, bio, rw) < 0) - goto out; - - bv.bv_len = bvec->bv_len - max_transfer_size; - bv.bv_offset += max_transfer_size; - if (zram_bvec_rw(zram, &bv, index+1, 0, bio, rw) < 0) - goto out; - } else - if (zram_bvec_rw(zram, bvec, index, offset, bio, rw) - < 0) - goto out; - - update_position(&index, &offset, bvec); - } - - set_bit(BIO_UPTODATE, &bio->bi_flags); - bio_endio(bio, 0); - return; - -out: - bio_io_error(bio); -} - -/* - * Handler function for all zram I/O requests. - */ -static void zram_make_request(struct request_queue *queue, struct bio *bio) -{ - struct zram *zram = queue->queuedata; - - down_read(&zram->init_lock); - if (unlikely(!zram->init_done)) - goto error; - - if (!valid_io_request(zram, bio)) { - atomic64_inc(&zram->stats.invalid_io); - goto error; - } - - __zram_make_request(zram, bio, bio_data_dir(bio)); - up_read(&zram->init_lock); - - return; - -error: - up_read(&zram->init_lock); - bio_io_error(bio); -} - -static void zram_slot_free_notify(struct block_device *bdev, - unsigned long index) -{ - struct zram *zram; - - zram = bdev->bd_disk->private_data; - down_write(&zram->lock); - zram_free_page(zram, index); - up_write(&zram->lock); - atomic64_inc(&zram->stats.notify_free); -} - -static const struct block_device_operations zram_devops = { - .swap_slot_free_notify = zram_slot_free_notify, - .owner = THIS_MODULE -}; - -static DEVICE_ATTR(disksize, S_IRUGO | S_IWUSR, - disksize_show, disksize_store); -static DEVICE_ATTR(initstate, S_IRUGO, initstate_show, NULL); -static DEVICE_ATTR(reset, S_IWUSR, NULL, reset_store); -static DEVICE_ATTR(num_reads, S_IRUGO, num_reads_show, NULL); -static DEVICE_ATTR(num_writes, S_IRUGO, num_writes_show, NULL); -static DEVICE_ATTR(invalid_io, S_IRUGO, invalid_io_show, NULL); -static DEVICE_ATTR(notify_free, S_IRUGO, notify_free_show, NULL); -static DEVICE_ATTR(zero_pages, S_IRUGO, zero_pages_show, NULL); -static DEVICE_ATTR(orig_data_size, S_IRUGO, orig_data_size_show, NULL); -static DEVICE_ATTR(compr_data_size, S_IRUGO, compr_data_size_show, NULL); -static DEVICE_ATTR(mem_used_total, S_IRUGO, mem_used_total_show, NULL); - -static struct attribute *zram_disk_attrs[] = { - &dev_attr_disksize.attr, - &dev_attr_initstate.attr, - &dev_attr_reset.attr, - &dev_attr_num_reads.attr, - &dev_attr_num_writes.attr, - &dev_attr_invalid_io.attr, - &dev_attr_notify_free.attr, - &dev_attr_zero_pages.attr, - &dev_attr_orig_data_size.attr, - &dev_attr_compr_data_size.attr, - &dev_attr_mem_used_total.attr, - NULL, -}; - -static struct attribute_group zram_disk_attr_group = { - .attrs = zram_disk_attrs, -}; - -static int create_device(struct zram *zram, int device_id) -{ - int ret = -ENOMEM; - - init_rwsem(&zram->lock); - init_rwsem(&zram->init_lock); - - zram->queue = blk_alloc_queue(GFP_KERNEL); - if (!zram->queue) { - pr_err("Error allocating disk queue for device %d\n", - device_id); - goto out; - } - - blk_queue_make_request(zram->queue, zram_make_request); - zram->queue->queuedata = zram; - - /* gendisk structure */ - zram->disk = alloc_disk(1); - if (!zram->disk) { - pr_warn("Error allocating disk structure for device %d\n", - device_id); - goto out_free_queue; - } - - zram->disk->major = zram_major; - zram->disk->first_minor = device_id; - zram->disk->fops = &zram_devops; - zram->disk->queue = zram->queue; - zram->disk->private_data = zram; - snprintf(zram->disk->disk_name, 16, "zram%d", device_id); - - /* Actual capacity set using syfs (/sys/block/zram<id>/disksize */ - set_capacity(zram->disk, 0); - - /* - * To ensure that we always get PAGE_SIZE aligned - * and n*PAGE_SIZED sized I/O requests. - */ - blk_queue_physical_block_size(zram->disk->queue, PAGE_SIZE); - blk_queue_logical_block_size(zram->disk->queue, - ZRAM_LOGICAL_BLOCK_SIZE); - blk_queue_io_min(zram->disk->queue, PAGE_SIZE); - blk_queue_io_opt(zram->disk->queue, PAGE_SIZE); - - add_disk(zram->disk); - - ret = sysfs_create_group(&disk_to_dev(zram->disk)->kobj, - &zram_disk_attr_group); - if (ret < 0) { - pr_warn("Error creating sysfs group"); - goto out_free_disk; - } - - zram->init_done = 0; - return 0; - -out_free_disk: - del_gendisk(zram->disk); - put_disk(zram->disk); -out_free_queue: - blk_cleanup_queue(zram->queue); -out: - return ret; -} - -static void destroy_device(struct zram *zram) -{ - sysfs_remove_group(&disk_to_dev(zram->disk)->kobj, - &zram_disk_attr_group); - - if (zram->disk) { - del_gendisk(zram->disk); - put_disk(zram->disk); - } - - if (zram->queue) - blk_cleanup_queue(zram->queue); -} - -static int __init zram_init(void) -{ - int ret, dev_id; - - if (num_devices > max_num_devices) { - pr_warn("Invalid value for num_devices: %u\n", - num_devices); - ret = -EINVAL; - goto out; - } - - zram_major = register_blkdev(0, "zram"); - if (zram_major <= 0) { - pr_warn("Unable to get major number\n"); - ret = -EBUSY; - goto out; - } - - /* Allocate the device array and initialize each one */ - zram_devices = kzalloc(num_devices * sizeof(struct zram), GFP_KERNEL); - if (!zram_devices) { - ret = -ENOMEM; - goto unregister; - } - - for (dev_id = 0; dev_id < num_devices; dev_id++) { - ret = create_device(&zram_devices[dev_id], dev_id); - if (ret) - goto free_devices; - } - - pr_info("Created %u device(s) ...\n", num_devices); - - return 0; - -free_devices: - while (dev_id) - destroy_device(&zram_devices[--dev_id]); - kfree(zram_devices); -unregister: - unregister_blkdev(zram_major, "zram"); -out: - return ret; -} - -static void __exit zram_exit(void) -{ - int i; - struct zram *zram; - - for (i = 0; i < num_devices; i++) { - zram = &zram_devices[i]; - - get_disk(zram->disk); - destroy_device(zram); - zram_reset_device(zram); - put_disk(zram->disk); - } - - unregister_blkdev(zram_major, "zram"); - - kfree(zram_devices); - pr_debug("Cleanup done!\n"); -} - -module_init(zram_init); -module_exit(zram_exit); - -module_param(num_devices, uint, 0); -MODULE_PARM_DESC(num_devices, "Number of zram devices"); - -MODULE_LICENSE("Dual BSD/GPL"); -MODULE_AUTHOR("Nitin Gupta <ngupta@vflare.org>"); -MODULE_DESCRIPTION("Compressed RAM Block Device"); diff --git a/drivers/staging/zram/zram_drv.h b/drivers/staging/zram/zram_drv.h deleted file mode 100644 index 9e57bfb29b4..00000000000 --- a/drivers/staging/zram/zram_drv.h +++ /dev/null @@ -1,115 +0,0 @@ -/* - * Compressed RAM block device - * - * Copyright (C) 2008, 2009, 2010 Nitin Gupta - * - * This code is released using a dual license strategy: BSD/GPL - * You can choose the licence that better fits your requirements. - * - * Released under the terms of 3-clause BSD License - * Released under the terms of GNU General Public License Version 2.0 - * - * Project home: http://compcache.googlecode.com - */ - -#ifndef _ZRAM_DRV_H_ -#define _ZRAM_DRV_H_ - -#include <linux/spinlock.h> -#include <linux/mutex.h> - -#include "../zsmalloc/zsmalloc.h" - -/* - * Some arbitrary value. This is just to catch - * invalid value for num_devices module parameter. - */ -static const unsigned max_num_devices = 32; - -/*-- Configurable parameters */ - -/* - * Pages that compress to size greater than this are stored - * uncompressed in memory. - */ -static const size_t max_zpage_size = PAGE_SIZE / 4 * 3; - -/* - * NOTE: max_zpage_size must be less than or equal to: - * ZS_MAX_ALLOC_SIZE. Otherwise, zs_malloc() would - * always return failure. - */ - -/*-- End of configurable params */ - -#define SECTOR_SHIFT 9 -#define SECTOR_SIZE (1 << SECTOR_SHIFT) -#define SECTORS_PER_PAGE_SHIFT (PAGE_SHIFT - SECTOR_SHIFT) -#define SECTORS_PER_PAGE (1 << SECTORS_PER_PAGE_SHIFT) -#define ZRAM_LOGICAL_BLOCK_SHIFT 12 -#define ZRAM_LOGICAL_BLOCK_SIZE (1 << ZRAM_LOGICAL_BLOCK_SHIFT) -#define ZRAM_SECTOR_PER_LOGICAL_BLOCK \ - (1 << (ZRAM_LOGICAL_BLOCK_SHIFT - SECTOR_SHIFT)) - -/* Flags for zram pages (table[page_no].flags) */ -enum zram_pageflags { - /* Page consists entirely of zeros */ - ZRAM_ZERO, - - __NR_ZRAM_PAGEFLAGS, -}; - -/*-- Data structures */ - -/* Allocated for each disk page */ -struct table { - unsigned long handle; - u16 size; /* object size (excluding header) */ - u8 count; /* object ref count (not yet used) */ - u8 flags; -} __aligned(4); - -/* - * All 64bit fields should only be manipulated by 64bit atomic accessors. - * All modifications to 32bit counter should be protected by zram->lock. - */ -struct zram_stats { - atomic64_t compr_size; /* compressed size of pages stored */ - atomic64_t num_reads; /* failed + successful */ - atomic64_t num_writes; /* --do-- */ - atomic64_t failed_reads; /* should NEVER! happen */ - atomic64_t failed_writes; /* can happen when memory is too low */ - atomic64_t invalid_io; /* non-page-aligned I/O requests */ - atomic64_t notify_free; /* no. of swap slot free notifications */ - u32 pages_zero; /* no. of zero filled pages */ - u32 pages_stored; /* no. of pages currently stored */ - u32 good_compress; /* % of pages with compression ratio<=50% */ - u32 bad_compress; /* % of pages with compression ratio>=75% */ -}; - -struct zram_meta { - void *compress_workmem; - void *compress_buffer; - struct table *table; - struct zs_pool *mem_pool; -}; - -struct zram { - struct zram_meta *meta; - struct rw_semaphore lock; /* protect compression buffers, table, - * 32bit stat counters against concurrent - * notifications, reads and writes */ - struct request_queue *queue; - struct gendisk *disk; - int init_done; - /* Prevent concurrent execution of device init, reset and R/W request */ - struct rw_semaphore init_lock; - /* - * This is the limit on amount of *uncompressed* worth of data - * we can store in a disk. - */ - u64 disksize; /* bytes */ - - struct zram_stats stats; -}; -#endif |