diff options
Diffstat (limited to 'drivers/staging/zram')
| -rw-r--r-- | drivers/staging/zram/Kconfig | 30 | ||||
| -rw-r--r-- | drivers/staging/zram/Makefile | 4 | ||||
| -rw-r--r-- | drivers/staging/zram/xvmalloc.c | 510 | ||||
| -rw-r--r-- | drivers/staging/zram/xvmalloc.h | 30 | ||||
| -rw-r--r-- | drivers/staging/zram/xvmalloc_int.h | 95 | ||||
| -rw-r--r-- | drivers/staging/zram/zram.txt | 76 | ||||
| -rw-r--r-- | drivers/staging/zram/zram_drv.c | 869 | ||||
| -rw-r--r-- | drivers/staging/zram/zram_drv.h | 135 | ||||
| -rw-r--r-- | drivers/staging/zram/zram_sysfs.c | 227 |
9 files changed, 0 insertions, 1976 deletions
diff --git a/drivers/staging/zram/Kconfig b/drivers/staging/zram/Kconfig deleted file mode 100644 index 3bec4dba3fe..00000000000 --- a/drivers/staging/zram/Kconfig +++ /dev/null @@ -1,30 +0,0 @@ -config XVMALLOC - bool - default n - -config ZRAM - tristate "Compressed RAM block device support" - depends on BLOCK && SYSFS - select XVMALLOC - 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: http://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 2a6d3213a75..00000000000 --- a/drivers/staging/zram/Makefile +++ /dev/null @@ -1,4 +0,0 @@ -zram-y := zram_drv.o zram_sysfs.o - -obj-$(CONFIG_ZRAM) += zram.o -obj-$(CONFIG_XVMALLOC) += xvmalloc.o
\ No newline at end of file diff --git a/drivers/staging/zram/xvmalloc.c b/drivers/staging/zram/xvmalloc.c deleted file mode 100644 index 1f9c5082b6d..00000000000 --- a/drivers/staging/zram/xvmalloc.c +++ /dev/null @@ -1,510 +0,0 @@ -/* - * xvmalloc memory allocator - * - * 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 - */ - -#ifdef CONFIG_ZRAM_DEBUG -#define DEBUG -#endif - -#include <linux/module.h> -#include <linux/kernel.h> -#include <linux/bitops.h> -#include <linux/errno.h> -#include <linux/highmem.h> -#include <linux/init.h> -#include <linux/string.h> -#include <linux/slab.h> - -#include "xvmalloc.h" -#include "xvmalloc_int.h" - -static void stat_inc(u64 *value) -{ - *value = *value + 1; -} - -static void stat_dec(u64 *value) -{ - *value = *value - 1; -} - -static int test_flag(struct block_header *block, enum blockflags flag) -{ - return block->prev & BIT(flag); -} - -static void set_flag(struct block_header *block, enum blockflags flag) -{ - block->prev |= BIT(flag); -} - -static void clear_flag(struct block_header *block, enum blockflags flag) -{ - block->prev &= ~BIT(flag); -} - -/* - * Given <page, offset> pair, provide a dereferencable pointer. - * This is called from xv_malloc/xv_free path, so it - * needs to be fast. - */ -static void *get_ptr_atomic(struct page *page, u16 offset, enum km_type type) -{ - unsigned char *base; - - base = kmap_atomic(page, type); - return base + offset; -} - -static void put_ptr_atomic(void *ptr, enum km_type type) -{ - kunmap_atomic(ptr, type); -} - -static u32 get_blockprev(struct block_header *block) -{ - return block->prev & PREV_MASK; -} - -static void set_blockprev(struct block_header *block, u16 new_offset) -{ - block->prev = new_offset | (block->prev & FLAGS_MASK); -} - -static struct block_header *BLOCK_NEXT(struct block_header *block) -{ - return (struct block_header *) - ((char *)block + block->size + XV_ALIGN); -} - -/* - * Get index of free list containing blocks of maximum size - * which is less than or equal to given size. - */ -static u32 get_index_for_insert(u32 size) -{ - if (unlikely(size > XV_MAX_ALLOC_SIZE)) - size = XV_MAX_ALLOC_SIZE; - size &= ~FL_DELTA_MASK; - return (size - XV_MIN_ALLOC_SIZE) >> FL_DELTA_SHIFT; -} - -/* - * Get index of free list having blocks of size greater than - * or equal to requested size. - */ -static u32 get_index(u32 size) -{ - if (unlikely(size < XV_MIN_ALLOC_SIZE)) - size = XV_MIN_ALLOC_SIZE; - size = ALIGN(size, FL_DELTA); - return (size - XV_MIN_ALLOC_SIZE) >> FL_DELTA_SHIFT; -} - -/** - * find_block - find block of at least given size - * @pool: memory pool to search from - * @size: size of block required - * @page: page containing required block - * @offset: offset within the page where block is located. - * - * Searches two level bitmap to locate block of at least - * the given size. If such a block is found, it provides - * <page, offset> to identify this block and returns index - * in freelist where we found this block. - * Otherwise, returns 0 and <page, offset> params are not touched. - */ -static u32 find_block(struct xv_pool *pool, u32 size, - struct page **page, u32 *offset) -{ - ulong flbitmap, slbitmap; - u32 flindex, slindex, slbitstart; - - /* There are no free blocks in this pool */ - if (!pool->flbitmap) - return 0; - - /* Get freelist index correspoding to this size */ - slindex = get_index(size); - slbitmap = pool->slbitmap[slindex / BITS_PER_LONG]; - slbitstart = slindex % BITS_PER_LONG; - - /* - * If freelist is not empty at this index, we found the - * block - head of this list. This is approximate best-fit match. - */ - if (test_bit(slbitstart, &slbitmap)) { - *page = pool->freelist[slindex].page; - *offset = pool->freelist[slindex].offset; - return slindex; - } - - /* - * No best-fit found. Search a bit further in bitmap for a free block. - * Second level bitmap consists of series of 32-bit chunks. Search - * further in the chunk where we expected a best-fit, starting from - * index location found above. - */ - slbitstart++; - slbitmap >>= slbitstart; - - /* Skip this search if we were already at end of this bitmap chunk */ - if ((slbitstart != BITS_PER_LONG) && slbitmap) { - slindex += __ffs(slbitmap) + 1; - *page = pool->freelist[slindex].page; - *offset = pool->freelist[slindex].offset; - return slindex; - } - - /* Now do a full two-level bitmap search to find next nearest fit */ - flindex = slindex / BITS_PER_LONG; - - flbitmap = (pool->flbitmap) >> (flindex + 1); - if (!flbitmap) - return 0; - - flindex += __ffs(flbitmap) + 1; - slbitmap = pool->slbitmap[flindex]; - slindex = (flindex * BITS_PER_LONG) + __ffs(slbitmap); - *page = pool->freelist[slindex].page; - *offset = pool->freelist[slindex].offset; - - return slindex; -} - -/* - * Insert block at <page, offset> in freelist of given pool. - * freelist used depends on block size. - */ -static void insert_block(struct xv_pool *pool, struct page *page, u32 offset, - struct block_header *block) -{ - u32 flindex, slindex; - struct block_header *nextblock; - - slindex = get_index_for_insert(block->size); - flindex = slindex / BITS_PER_LONG; - - block->link.prev_page = NULL; - block->link.prev_offset = 0; - block->link.next_page = pool->freelist[slindex].page; - block->link.next_offset = pool->freelist[slindex].offset; - pool->freelist[slindex].page = page; - pool->freelist[slindex].offset = offset; - - if (block->link.next_page) { - nextblock = get_ptr_atomic(block->link.next_page, - block->link.next_offset, KM_USER1); - nextblock->link.prev_page = page; - nextblock->link.prev_offset = offset; - put_ptr_atomic(nextblock, KM_USER1); - /* If there was a next page then the free bits are set. */ - return; - } - - __set_bit(slindex % BITS_PER_LONG, &pool->slbitmap[flindex]); - __set_bit(flindex, &pool->flbitmap); -} - -/* - * Remove block from freelist. Index 'slindex' identifies the freelist. - */ -static void remove_block(struct xv_pool *pool, struct page *page, u32 offset, - struct block_header *block, u32 slindex) -{ - u32 flindex = slindex / BITS_PER_LONG; - struct block_header *tmpblock; - - if (block->link.prev_page) { - tmpblock = get_ptr_atomic(block->link.prev_page, - block->link.prev_offset, KM_USER1); - tmpblock->link.next_page = block->link.next_page; - tmpblock->link.next_offset = block->link.next_offset; - put_ptr_atomic(tmpblock, KM_USER1); - } - - if (block->link.next_page) { - tmpblock = get_ptr_atomic(block->link.next_page, - block->link.next_offset, KM_USER1); - tmpblock->link.prev_page = block->link.prev_page; - tmpblock->link.prev_offset = block->link.prev_offset; - put_ptr_atomic(tmpblock, KM_USER1); - } - - /* Is this block is at the head of the freelist? */ - if (pool->freelist[slindex].page == page - && pool->freelist[slindex].offset == offset) { - - pool->freelist[slindex].page = block->link.next_page; - pool->freelist[slindex].offset = block->link.next_offset; - - if (pool->freelist[slindex].page) { - struct block_header *tmpblock; - tmpblock = get_ptr_atomic(pool->freelist[slindex].page, - pool->freelist[slindex].offset, - KM_USER1); - tmpblock->link.prev_page = NULL; - tmpblock->link.prev_offset = 0; - put_ptr_atomic(tmpblock, KM_USER1); - } else { - /* This freelist bucket is empty */ - __clear_bit(slindex % BITS_PER_LONG, - &pool->slbitmap[flindex]); - if (!pool->slbitmap[flindex]) - __clear_bit(flindex, &pool->flbitmap); - } - } - - block->link.prev_page = NULL; - block->link.prev_offset = 0; - block->link.next_page = NULL; - block->link.next_offset = 0; -} - -/* - * Allocate a page and add it to freelist of given pool. - */ -static int grow_pool(struct xv_pool *pool, gfp_t flags) -{ - struct page *page; - struct block_header *block; - - page = alloc_page(flags); - if (unlikely(!page)) - return -ENOMEM; - - stat_inc(&pool->total_pages); - - spin_lock(&pool->lock); - block = get_ptr_atomic(page, 0, KM_USER0); - - block->size = PAGE_SIZE - XV_ALIGN; - set_flag(block, BLOCK_FREE); - clear_flag(block, PREV_FREE); - set_blockprev(block, 0); - - insert_block(pool, page, 0, block); - - put_ptr_atomic(block, KM_USER0); - spin_unlock(&pool->lock); - - return 0; -} - -/* - * Create a memory pool. Allocates freelist, bitmaps and other - * per-pool metadata. - */ -struct xv_pool *xv_create_pool(void) -{ - u32 ovhd_size; - struct xv_pool *pool; - - ovhd_size = roundup(sizeof(*pool), PAGE_SIZE); - pool = kzalloc(ovhd_size, GFP_KERNEL); - if (!pool) - return NULL; - - spin_lock_init(&pool->lock); - - return pool; -} -EXPORT_SYMBOL_GPL(xv_create_pool); - -void xv_destroy_pool(struct xv_pool *pool) -{ - kfree(pool); -} -EXPORT_SYMBOL_GPL(xv_destroy_pool); - -/** - * xv_malloc - Allocate block of given size from pool. - * @pool: pool to allocate from - * @size: size of block to allocate - * @page: page no. that holds the object - * @offset: location of object within page - * - * On success, <page, offset> identifies block allocated - * and 0 is returned. On failure, <page, offset> is set to - * 0 and -ENOMEM is returned. - * - * Allocation requests with size > XV_MAX_ALLOC_SIZE will fail. - */ -int xv_malloc(struct xv_pool *pool, u32 size, struct page **page, - u32 *offset, gfp_t flags) -{ - int error; - u32 index, tmpsize, origsize, tmpoffset; - struct block_header *block, *tmpblock; - - *page = NULL; - *offset = 0; - origsize = size; - - if (unlikely(!size || size > XV_MAX_ALLOC_SIZE)) - return -ENOMEM; - - size = ALIGN(size, XV_ALIGN); - - spin_lock(&pool->lock); - - index = find_block(pool, size, page, offset); - - if (!*page) { - spin_unlock(&pool->lock); - if (flags & GFP_NOWAIT) - return -ENOMEM; - error = grow_pool(pool, flags); - if (unlikely(error)) - return error; - - spin_lock(&pool->lock); - index = find_block(pool, size, page, offset); - } - - if (!*page) { - spin_unlock(&pool->lock); - return -ENOMEM; - } - - block = get_ptr_atomic(*page, *offset, KM_USER0); - - remove_block(pool, *page, *offset, block, index); - - /* Split the block if required */ - tmpoffset = *offset + size + XV_ALIGN; - tmpsize = block->size - size; - tmpblock = (struct block_header *)((char *)block + size + XV_ALIGN); - if (tmpsize) { - tmpblock->size = tmpsize - XV_ALIGN; - set_flag(tmpblock, BLOCK_FREE); - clear_flag(tmpblock, PREV_FREE); - - set_blockprev(tmpblock, *offset); - if (tmpblock->size >= XV_MIN_ALLOC_SIZE) - insert_block(pool, *page, tmpoffset, tmpblock); - - if (tmpoffset + XV_ALIGN + tmpblock->size != PAGE_SIZE) { - tmpblock = BLOCK_NEXT(tmpblock); - set_blockprev(tmpblock, tmpoffset); - } - } else { - /* This block is exact fit */ - if (tmpoffset != PAGE_SIZE) - clear_flag(tmpblock, PREV_FREE); - } - - block->size = origsize; - clear_flag(block, BLOCK_FREE); - - put_ptr_atomic(block, KM_USER0); - spin_unlock(&pool->lock); - - *offset += XV_ALIGN; - - return 0; -} -EXPORT_SYMBOL_GPL(xv_malloc); - -/* - * Free block identified with <page, offset> - */ -void xv_free(struct xv_pool *pool, struct page *page, u32 offset) -{ - void *page_start; - struct block_header *block, *tmpblock; - - offset -= XV_ALIGN; - - spin_lock(&pool->lock); - - page_start = get_ptr_atomic(page, 0, KM_USER0); - block = (struct block_header *)((char *)page_start + offset); - - /* Catch double free bugs */ - BUG_ON(test_flag(block, BLOCK_FREE)); - - block->size = ALIGN(block->size, XV_ALIGN); - - tmpblock = BLOCK_NEXT(block); - if (offset + block->size + XV_ALIGN == PAGE_SIZE) - tmpblock = NULL; - - /* Merge next block if its free */ - if (tmpblock && test_flag(tmpblock, BLOCK_FREE)) { - /* - * Blocks smaller than XV_MIN_ALLOC_SIZE - * are not inserted in any free list. - */ - if (tmpblock->size >= XV_MIN_ALLOC_SIZE) { - remove_block(pool, page, - offset + block->size + XV_ALIGN, tmpblock, - get_index_for_insert(tmpblock->size)); - } - block->size += tmpblock->size + XV_ALIGN; - } - - /* Merge previous block if its free */ - if (test_flag(block, PREV_FREE)) { - tmpblock = (struct block_header *)((char *)(page_start) + - get_blockprev(block)); - offset = offset - tmpblock->size - XV_ALIGN; - - if (tmpblock->size >= XV_MIN_ALLOC_SIZE) - remove_block(pool, page, offset, tmpblock, - get_index_for_insert(tmpblock->size)); - - tmpblock->size += block->size + XV_ALIGN; - block = tmpblock; - } - - /* No used objects in this page. Free it. */ - if (block->size == PAGE_SIZE - XV_ALIGN) { - put_ptr_atomic(page_start, KM_USER0); - spin_unlock(&pool->lock); - - __free_page(page); - stat_dec(&pool->total_pages); - return; - } - - set_flag(block, BLOCK_FREE); - if (block->size >= XV_MIN_ALLOC_SIZE) - insert_block(pool, page, offset, block); - - if (offset + block->size + XV_ALIGN != PAGE_SIZE) { - tmpblock = BLOCK_NEXT(block); - set_flag(tmpblock, PREV_FREE); - set_blockprev(tmpblock, offset); - } - - put_ptr_atomic(page_start, KM_USER0); - spin_unlock(&pool->lock); -} -EXPORT_SYMBOL_GPL(xv_free); - -u32 xv_get_object_size(void *obj) -{ - struct block_header *blk; - - blk = (struct block_header *)((char *)(obj) - XV_ALIGN); - return blk->size; -} -EXPORT_SYMBOL_GPL(xv_get_object_size); - -/* - * Returns total memory used by allocator (userdata + metadata) - */ -u64 xv_get_total_size_bytes(struct xv_pool *pool) -{ - return pool->total_pages << PAGE_SHIFT; -} -EXPORT_SYMBOL_GPL(xv_get_total_size_bytes); diff --git a/drivers/staging/zram/xvmalloc.h b/drivers/staging/zram/xvmalloc.h deleted file mode 100644 index 5b1a81aa5fa..00000000000 --- a/drivers/staging/zram/xvmalloc.h +++ /dev/null @@ -1,30 +0,0 @@ -/* - * xvmalloc memory allocator - * - * 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 - */ - -#ifndef _XV_MALLOC_H_ -#define _XV_MALLOC_H_ - -#include <linux/types.h> - -struct xv_pool; - -struct xv_pool *xv_create_pool(void); -void xv_destroy_pool(struct xv_pool *pool); - -int xv_malloc(struct xv_pool *pool, u32 size, struct page **page, - u32 *offset, gfp_t flags); -void xv_free(struct xv_pool *pool, struct page *page, u32 offset); - -u32 xv_get_object_size(void *obj); -u64 xv_get_total_size_bytes(struct xv_pool *pool); - -#endif diff --git a/drivers/staging/zram/xvmalloc_int.h b/drivers/staging/zram/xvmalloc_int.h deleted file mode 100644 index b5f1f7febcf..00000000000 --- a/drivers/staging/zram/xvmalloc_int.h +++ /dev/null @@ -1,95 +0,0 @@ -/* - * xvmalloc memory allocator - * - * 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 - */ - -#ifndef _XV_MALLOC_INT_H_ -#define _XV_MALLOC_INT_H_ - -#include <linux/kernel.h> -#include <linux/types.h> - -/* User configurable params */ - -/* Must be power of two */ -#ifdef CONFIG_64BIT -#define XV_ALIGN_SHIFT 3 -#else -#define XV_ALIGN_SHIFT 2 -#endif -#define XV_ALIGN (1 << XV_ALIGN_SHIFT) -#define XV_ALIGN_MASK (XV_ALIGN - 1) - -/* This must be greater than sizeof(link_free) */ -#define XV_MIN_ALLOC_SIZE 32 -#define XV_MAX_ALLOC_SIZE (PAGE_SIZE - XV_ALIGN) - -/* - * Free lists are separated by FL_DELTA bytes - * This value is 3 for 4k pages and 4 for 64k pages, for any - * other page size, a conservative (PAGE_SHIFT - 9) is used. - */ -#if PAGE_SHIFT == 16 -#define FL_DELTA_SHIFT 4 -#else -#define FL_DELTA_SHIFT (PAGE_SHIFT - 9) -#endif -#define FL_DELTA (1 << FL_DELTA_SHIFT) -#define FL_DELTA_MASK (FL_DELTA - 1) -#define NUM_FREE_LISTS ((XV_MAX_ALLOC_SIZE - XV_MIN_ALLOC_SIZE) \ - / FL_DELTA + 1) - -#define MAX_FLI DIV_ROUND_UP(NUM_FREE_LISTS, BITS_PER_LONG) - -/* End of user params */ - -enum blockflags { - BLOCK_FREE, - PREV_FREE, - __NR_BLOCKFLAGS, -}; - -#define FLAGS_MASK XV_ALIGN_MASK -#define PREV_MASK (~FLAGS_MASK) - -struct freelist_entry { - struct page *page; - u16 offset; - u16 pad; -}; - -struct link_free { - struct page *prev_page; - struct page *next_page; - u16 prev_offset; - u16 next_offset; -}; - -struct block_header { - union { - /* This common header must be XV_ALIGN bytes */ - u8 common[XV_ALIGN]; - struct { - u16 size; - u16 prev; - }; - }; - struct link_free link; -}; - -struct xv_pool { - ulong flbitmap; - ulong slbitmap[MAX_FLI]; - u64 total_pages; /* stats */ - struct freelist_entry freelist[NUM_FREE_LISTS]; - spinlock_t lock; -}; - -#endif diff --git a/drivers/staging/zram/zram.txt b/drivers/staging/zram/zram.txt deleted file mode 100644 index 5f75d298756..00000000000 --- a/drivers/staging/zram/zram.txt +++ /dev/null @@ -1,76 +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 (Optional): - Set disk size by writing the value to sysfs node 'disksize' - (in bytes). If disksize is not given, default value of 25% - of RAM is used. - - # Initialize /dev/zram0 with 50MB disksize - echo $((50*1024*1024)) > /sys/block/zram0/disksize - - NOTE: disksize cannot be changed if the disk contains any - data. So, for such a disk, you need to issue 'reset' (see below) - before you can change its 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). - - -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 2a2a92d389e..00000000000 --- a/drivers/staging/zram/zram_drv.c +++ /dev/null @@ -1,869 +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; -struct zram *zram_devices; - -/* Module params (documentation at end) */ -unsigned int zram_num_devices; - -static void zram_stat_inc(u32 *v) -{ - *v = *v + 1; -} - -static void zram_stat_dec(u32 *v) -{ - *v = *v - 1; -} - -static void zram_stat64_add(struct zram *zram, u64 *v, u64 inc) -{ - spin_lock(&zram->stat64_lock); - *v = *v + inc; - spin_unlock(&zram->stat64_lock); -} - -static void zram_stat64_sub(struct zram *zram, u64 *v, u64 dec) -{ - spin_lock(&zram->stat64_lock); - *v = *v - dec; - spin_unlock(&zram->stat64_lock); -} - -static void zram_stat64_inc(struct zram *zram, u64 *v) -{ - zram_stat64_add(zram, v, 1); -} - -static int zram_test_flag(struct zram *zram, u32 index, - enum zram_pageflags flag) -{ - return zram->table[index].flags & BIT(flag); -} - -static void zram_set_flag(struct zram *zram, u32 index, - enum zram_pageflags flag) -{ - zram->table[index].flags |= BIT(flag); -} - -static void zram_clear_flag(struct zram *zram, u32 index, - enum zram_pageflags flag) -{ - zram->table[index].flags &= ~BIT(flag); -} - -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 zram_set_disksize(struct zram *zram, size_t totalram_bytes) -{ - if (!zram->disksize) { - pr_info( - "disk size not provided. You can use disksize_kb module " - "param to specify size.\nUsing default: (%u%% of RAM).\n", - default_disksize_perc_ram - ); - zram->disksize = default_disksize_perc_ram * - (totalram_bytes / 100); - } - - if (zram->disksize > 2 * (totalram_bytes)) { - 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: %zu kB\n" - "\tSize you selected: %llu kB\n" - "Continuing anyway ...\n", - totalram_bytes >> 10, zram->disksize - ); - } - - zram->disksize &= PAGE_MASK; -} - -static void zram_free_page(struct zram *zram, size_t index) -{ - u32 clen; - void *obj; - - struct page *page = zram->table[index].page; - u32 offset = zram->table[index].offset; - - if (unlikely(!page)) { - /* - * No memory is allocated for zero filled pages. - * Simply clear zero page flag. - */ - if (zram_test_flag(zram, index, ZRAM_ZERO)) { - zram_clear_flag(zram, index, ZRAM_ZERO); - zram_stat_dec(&zram->stats.pages_zero); - } - return; - } - - if (unlikely(zram_test_flag(zram, index, ZRAM_UNCOMPRESSED))) { - clen = PAGE_SIZE; - __free_page(page); - zram_clear_flag(zram, index, ZRAM_UNCOMPRESSED); - zram_stat_dec(&zram->stats.pages_expand); - goto out; - } - - obj = kmap_atomic(page, KM_USER0) + offset; - clen = xv_get_object_size(obj) - sizeof(struct zobj_header); - kunmap_atomic(obj, KM_USER0); - - xv_free(zram->mem_pool, page, offset); - if (clen <= PAGE_SIZE / 2) - zram_stat_dec(&zram->stats.good_compress); - -out: - zram_stat64_sub(zram, &zram->stats.compr_size, clen); - zram_stat_dec(&zram->stats.pages_stored); - - zram->table[index].page = NULL; - zram->table[index].offset = 0; -} - -static void handle_zero_page(struct bio_vec *bvec) -{ - struct page *page = bvec->bv_page; - void *user_mem; - - user_mem = kmap_atomic(page, KM_USER0); - memset(user_mem + bvec->bv_offset, 0, bvec->bv_len); - kunmap_atomic(user_mem, KM_USER0); - - flush_dcache_page(page); -} - -static void handle_uncompressed_page(struct zram *zram, struct bio_vec *bvec, - u32 index, int offset) -{ - struct page *page = bvec->bv_page; - unsigned char *user_mem, *cmem; - - user_mem = kmap_atomic(page, KM_USER0); - cmem = kmap_atomic(zram->table[index].page, KM_USER1); - - memcpy(user_mem + bvec->bv_offset, cmem + offset, bvec->bv_len); - kunmap_atomic(cmem, KM_USER1); - kunmap_atomic(user_mem, KM_USER0); - - flush_dcache_page(page); -} - -static inline int is_partial_io(struct bio_vec *bvec) -{ - return bvec->bv_len != PAGE_SIZE; -} - -static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec, - u32 index, int offset, struct bio *bio) -{ - int ret; - size_t clen; - struct page *page; - struct zobj_header *zheader; - unsigned char *user_mem, *cmem, *uncmem = NULL; - - page = bvec->bv_page; - - if (zram_test_flag(zram, index, ZRAM_ZERO)) { - handle_zero_page(bvec); - return 0; - } - - /* Requested page is not present in compressed area */ - if (unlikely(!zram->table[index].page)) { - pr_debug("Read before write: sector=%lu, size=%u", - (ulong)(bio->bi_sector), bio->bi_size); - handle_zero_page(bvec); - return 0; - } - - /* Page is stored uncompressed since it's incompressible */ - if (unlikely(zram_test_flag(zram, index, ZRAM_UNCOMPRESSED))) { - handle_uncompressed_page(zram, bvec, index, offset); - return 0; - } - - if (is_partial_io(bvec)) { - /* Use a temporary buffer to decompress the page */ - uncmem = kmalloc(PAGE_SIZE, GFP_KERNEL); - if (!uncmem) { - pr_info("Error allocating temp memory!\n"); - return -ENOMEM; - } - } - - user_mem = kmap_atomic(page, KM_USER0); - if (!is_partial_io(bvec)) - uncmem = user_mem; - clen = PAGE_SIZE; - - cmem = kmap_atomic(zram->table[index].page, KM_USER1) + - zram->table[index].offset; - - ret = lzo1x_decompress_safe(cmem + sizeof(*zheader), - xv_get_object_size(cmem) - sizeof(*zheader), - uncmem, &clen); - - if (is_partial_io(bvec)) { - memcpy(user_mem + bvec->bv_offset, uncmem + offset, - bvec->bv_len); - kfree(uncmem); - } - - kunmap_atomic(cmem, KM_USER1); - kunmap_atomic(user_mem, KM_USER0); - - /* 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); - zram_stat64_inc(zram, &zram->stats.failed_reads); - return ret; - } - - flush_dcache_page(page); - - return 0; -} - -static int zram_read_before_write(struct zram *zram, char *mem, u32 index) -{ - int ret; - size_t clen = PAGE_SIZE; - struct zobj_header *zheader; - unsigned char *cmem; - - if (zram_test_flag(zram, index, ZRAM_ZERO) || - !zram->table[index].page) { - memset(mem, 0, PAGE_SIZE); - return 0; - } - - cmem = kmap_atomic(zram->table[index].page, KM_USER0) + - zram->table[index].offset; - - /* Page is stored uncompressed since it's incompressible */ - if (unlikely(zram_test_flag(zram, index, ZRAM_UNCOMPRESSED))) { - memcpy(mem, cmem, PAGE_SIZE); - kunmap_atomic(cmem, KM_USER0); - return 0; - } - - ret = lzo1x_decompress_safe(cmem + sizeof(*zheader), - xv_get_object_size(cmem) - sizeof(*zheader), - mem, &clen); - kunmap_atomic(cmem, KM_USER0); - - /* 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); - zram_stat64_inc(zram, &zram->stats.failed_reads); - return ret; - } - - return 0; -} - -static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index, - int offset) -{ - int ret; - u32 store_offset; - size_t clen; - struct zobj_header *zheader; - struct page *page, *page_store; - unsigned char *user_mem, *cmem, *src, *uncmem = NULL; - - page = bvec->bv_page; - src = zram->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_KERNEL); - if (!uncmem) { - pr_info("Error allocating temp memory!\n"); - ret = -ENOMEM; - goto out; - } - ret = zram_read_before_write(zram, uncmem, index); - if (ret) { - kfree(uncmem); - goto out; - } - } - - /* - * System overwrites unused sectors. Free memory associated - * with this sector now. - */ - if (zram->table[index].page || - zram_test_flag(zram, index, ZRAM_ZERO)) - zram_free_page(zram, index); - - user_mem = kmap_atomic(page, KM_USER0); - - if (is_partial_io(bvec)) - memcpy(uncmem + offset, user_mem + bvec->bv_offset, - bvec->bv_len); - else - uncmem = user_mem; - - if (page_zero_filled(uncmem)) { - kunmap_atomic(user_mem, KM_USER0); - if (is_partial_io(bvec)) - kfree(uncmem); - zram_stat_inc(&zram->stats.pages_zero); - zram_set_flag(zram, index, ZRAM_ZERO); - ret = 0; - goto out; - } - - ret = lzo1x_1_compress(uncmem, PAGE_SIZE, src, &clen, - zram->compress_workmem); - - kunmap_atomic(user_mem, KM_USER0); - if (is_partial_io(bvec)) - kfree(uncmem); - - if (unlikely(ret != LZO_E_OK)) { - pr_err("Compression failed! err=%d\n", ret); - goto out; - } - - /* - * Page is incompressible. Store it as-is (uncompressed) - * since we do not want to return too many disk write - * errors which has side effect of hanging the system. - */ - if (unlikely(clen > max_zpage_size)) { - clen = PAGE_SIZE; - page_store = alloc_page(GFP_NOIO | __GFP_HIGHMEM); - if (unlikely(!page_store)) { - pr_info("Error allocating memory for " - "incompressible page: %u\n", index); - ret = -ENOMEM; - goto out; - } - - store_offset = 0; - zram_set_flag(zram, index, ZRAM_UNCOMPRESSED); - zram_stat_inc(&zram->stats.pages_expand); - zram->table[index].page = page_store; - src = kmap_atomic(page, KM_USER0); - goto memstore; - } - - if (xv_malloc(zram->mem_pool, clen + sizeof(*zheader), - &zram->table[index].page, &store_offset, - GFP_NOIO | __GFP_HIGHMEM)) { - pr_info("Error allocating memory for compressed " - "page: %u, size=%zu\n", index, clen); - ret = -ENOMEM; - goto out; - } - -memstore: - zram->table[index].offset = store_offset; - - cmem = kmap_atomic(zram->table[index].page, KM_USER1) + - zram->table[index].offset; - -#if 0 - /* Back-reference needed for memory defragmentation */ - if (!zram_test_flag(zram, index, ZRAM_UNCOMPRESSED)) { - zheader = (struct zobj_header *)cmem; - zheader->table_idx = index; - cmem += sizeof(*zheader); - } -#endif - - memcpy(cmem, src, clen); - - kunmap_atomic(cmem, KM_USER1); - if (unlikely(zram_test_flag(zram, index, ZRAM_UNCOMPRESSED))) - kunmap_atomic(src, KM_USER0); - - /* Update stats */ - zram_stat64_add(zram, &zram->stats.compr_size, clen); - zram_stat_inc(&zram->stats.pages_stored); - if (clen <= PAGE_SIZE / 2) - zram_stat_inc(&zram->stats.good_compress); - - return 0; - -out: - if (ret) - zram_stat64_inc(zram, &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 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 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: - zram_stat64_inc(zram, &zram->stats.num_reads); - break; - case WRITE: - zram_stat64_inc(zram, &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); -} - -/* - * Check if request is within bounds and aligned on zram logical blocks. - */ -static inline int valid_io_request(struct zram *zram, struct bio *bio) -{ - if (unlikely( - (bio->bi_sector >= (zram->disksize >> SECTOR_SHIFT)) || - (bio->bi_sector & (ZRAM_SECTOR_PER_LOGICAL_BLOCK - 1)) || - (bio->bi_size & (ZRAM_LOGICAL_BLOCK_SIZE - 1)))) { - - return 0; - } - - /* I/O request is valid */ - return 1; -} - -/* - * 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; - - if (unlikely(!zram->init_done) && zram_init_device(zram)) - goto error; - - down_read(&zram->init_lock); - if (unlikely(!zram->init_done)) - goto error_unlock; - - if (!valid_io_request(zram, bio)) { - zram_stat64_inc(zram, &zram->stats.invalid_io); - goto error_unlock; - } - - __zram_make_request(zram, bio, bio_data_dir(bio)); - up_read(&zram->init_lock); - - return; - -error_unlock: - up_read(&zram->init_lock); -error: - bio_io_error(bio); -} - -void __zram_reset_device(struct zram *zram) -{ - size_t index; - - zram->init_done = 0; - - /* Free various per-device buffers */ - kfree(zram->compress_workmem); - free_pages((unsigned long)zram->compress_buffer, 1); - - zram->compress_workmem = NULL; - zram->compress_buffer = NULL; - - /* Free all pages that are still in this zram device */ - for (index = 0; index < zram->disksize >> PAGE_SHIFT; index++) { - struct page *page; - u16 offset; - - page = zram->table[index].page; - offset = zram->table[index].offset; - - if (!page) - continue; - - if (unlikely(zram_test_flag(zram, index, ZRAM_UNCOMPRESSED))) - __free_page(page); - else - xv_free(zram->mem_pool, page, offset); - } - - vfree(zram->table); - zram->table = NULL; - - xv_destroy_pool(zram->mem_pool); - zram->mem_pool = NULL; - - /* Reset stats */ - memset(&zram->stats, 0, sizeof(zram->stats)); - - zram->disksize = 0; -} - -void zram_reset_device(struct zram *zram) -{ - down_write(&zram->init_lock); - __zram_reset_device(zram); - up_write(&zram->init_lock); -} - -int zram_init_device(struct zram *zram) -{ - int ret; - size_t num_pages; - - down_write(&zram->init_lock); - - if (zram->init_done) { - up_write(&zram->init_lock); - return 0; - } - - zram_set_disksize(zram, totalram_pages << PAGE_SHIFT); - - zram->compress_workmem = kzalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL); - if (!zram->compress_workmem) { - pr_err("Error allocating compressor working memory!\n"); - ret = -ENOMEM; - goto fail_no_table; - } - - zram->compress_buffer = - (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 1); - if (!zram->compress_buffer) { - pr_err("Error allocating compressor buffer space\n"); - ret = -ENOMEM; - goto fail_no_table; - } - - num_pages = zram->disksize >> PAGE_SHIFT; - zram->table = vzalloc(num_pages * sizeof(*zram->table)); - if (!zram->table) { - pr_err("Error allocating zram address table\n"); - ret = -ENOMEM; - goto fail_no_table; - } - - set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT); - - /* zram devices sort of resembles non-rotational disks */ - queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zram->disk->queue); - - zram->mem_pool = xv_create_pool(); - if (!zram->mem_pool) { - pr_err("Error creating memory pool\n"); - ret = -ENOMEM; - goto fail; - } - - zram->init_done = 1; - up_write(&zram->init_lock); - - pr_debug("Initialization done!\n"); - return 0; - -fail_no_table: - /* To prevent accessing table entries during cleanup */ - zram->disksize = 0; -fail: - __zram_reset_device(zram); - up_write(&zram->init_lock); - pr_err("Initialization failed: err=%d\n", ret); - return ret; -} - -static void zram_slot_free_notify(struct block_device *bdev, - unsigned long index) -{ - struct zram *zram; - - zram = bdev->bd_disk->private_data; - zram_free_page(zram, index); - zram_stat64_inc(zram, &zram->stats.notify_free); -} - -static const struct block_device_operations zram_devops = { - .swap_slot_free_notify = zram_slot_free_notify, - .owner = THIS_MODULE -}; - -static int create_device(struct zram *zram, int device_id) -{ - int ret = 0; - - init_rwsem(&zram->lock); - init_rwsem(&zram->init_lock); - spin_lock_init(&zram->stat64_lock); - - zram->queue = blk_alloc_queue(GFP_KERNEL); - if (!zram->queue) { - pr_err("Error allocating disk queue for device %d\n", - device_id); - ret = -ENOMEM; - 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) { - blk_cleanup_queue(zram->queue); - pr_warning("Error allocating disk structure for device %d\n", - device_id); - ret = -ENOMEM; - goto out; - } - - 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_warning("Error creating sysfs group"); - goto out; - } - - zram->init_done = 0; - -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 (zram_num_devices > max_num_devices) { - pr_warning("Invalid value for num_devices: %u\n", - zram_num_devices); - ret = -EINVAL; - goto out; - } - - zram_major = register_blkdev(0, "zram"); - if (zram_major <= 0) { - pr_warning("Unable to get major number\n"); - ret = -EBUSY; - goto out; - } - - if (!zram_num_devices) { - pr_info("num_devices not specified. Using default: 1\n"); - zram_num_devices = 1; - } - - /* Allocate the device array and initialize each one */ - pr_info("Creating %u devices ...\n", zram_num_devices); - zram_devices = kzalloc(zram_num_devices * sizeof(struct zram), GFP_KERNEL); - if (!zram_devices) { - ret = -ENOMEM; - goto unregister; - } - - for (dev_id = 0; dev_id < zram_num_devices; dev_id++) { - ret = create_device(&zram_devices[dev_id], dev_id); - if (ret) - goto free_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 < zram_num_devices; i++) { - zram = &zram_devices[i]; - - destroy_device(zram); - if (zram->init_done) - zram_reset_device(zram); - } - - unregister_blkdev(zram_major, "zram"); - - kfree(zram_devices); - pr_debug("Cleanup done!\n"); -} - -module_param(zram_num_devices, uint, 0); -MODULE_PARM_DESC(zram_num_devices, "Number of zram devices"); - -module_init(zram_init); -module_exit(zram_exit); - -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 e5cd2469b6a..00000000000 --- a/drivers/staging/zram/zram_drv.h +++ /dev/null @@ -1,135 +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 "xvmalloc.h" - -/* - * Some arbitrary value. This is just to catch - * invalid value for num_devices module parameter. - */ -static const unsigned max_num_devices = 32; - -/* - * Stored at beginning of each compressed object. - * - * It stores back-reference to table entry which points to this - * object. This is required to support memory defragmentation. - */ -struct zobj_header { -#if 0 - u32 table_idx; -#endif -}; - -/*-- Configurable parameters */ - -/* Default zram disk size: 25% of total RAM */ -static const unsigned default_disksize_perc_ram = 25; - -/* - * 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: - * XV_MAX_ALLOC_SIZE - sizeof(struct zobj_header) - * otherwise, xv_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 is stored uncompressed */ - ZRAM_UNCOMPRESSED, - - /* Page consists entirely of zeros */ - ZRAM_ZERO, - - __NR_ZRAM_PAGEFLAGS, -}; - -/*-- Data structures */ - -/* Allocated for each disk page */ -struct table { - struct page *page; - u16 offset; - u8 count; /* object ref count (not yet used) */ - u8 flags; -} __attribute__((aligned(4))); - -struct zram_stats { - u64 compr_size; /* compressed size of pages stored */ - u64 num_reads; /* failed + successful */ - u64 num_writes; /* --do-- */ - u64 failed_reads; /* should NEVER! happen */ - u64 failed_writes; /* can happen when memory is too low */ - u64 invalid_io; /* non-page-aligned I/O requests */ - u64 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 pages_expand; /* % of incompressible pages */ -}; - -struct zram { - struct xv_pool *mem_pool; - void *compress_workmem; - void *compress_buffer; - struct table *table; - spinlock_t stat64_lock; /* protect 64-bit stats */ - struct rw_semaphore lock; /* protect compression buffers and table - * against concurrent read 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; -}; - -extern struct zram *zram_devices; -extern unsigned int zram_num_devices; -#ifdef CONFIG_SYSFS -extern struct attribute_group zram_disk_attr_group; -#endif - -extern int zram_init_device(struct zram *zram); -extern void __zram_reset_device(struct zram *zram); - -#endif diff --git a/drivers/staging/zram/zram_sysfs.c b/drivers/staging/zram/zram_sysfs.c deleted file mode 100644 index d521122826f..00000000000 --- a/drivers/staging/zram/zram_sysfs.c +++ /dev/null @@ -1,227 +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/ - */ - -#include <linux/device.h> -#include <linux/genhd.h> -#include <linux/mm.h> - -#include "zram_drv.h" - -static u64 zram_stat64_read(struct zram *zram, u64 *v) -{ - u64 val; - - spin_lock(&zram->stat64_lock); - val = *v; - spin_unlock(&zram->stat64_lock); - - return val; -} - -static struct zram *dev_to_zram(struct device *dev) -{ - int i; - struct zram *zram = NULL; - - for (i = 0; i < zram_num_devices; i++) { - zram = &zram_devices[i]; - if (disk_to_dev(zram->disk) == dev) - break; - } - - return zram; -} - -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 disksize_store(struct device *dev, - struct device_attribute *attr, const char *buf, size_t len) -{ - int ret; - u64 disksize; - struct zram *zram = dev_to_zram(dev); - - ret = kstrtoull(buf, 10, &disksize); - if (ret) - return ret; - - down_write(&zram->init_lock); - if (zram->init_done) { - up_write(&zram->init_lock); - pr_info("Cannot change disksize for initialized device\n"); - return -EBUSY; - } - - zram->disksize = PAGE_ALIGN(disksize); - set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT); - up_write(&zram->init_lock); - - return len; -} - -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 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); - - down_write(&zram->init_lock); - if (zram->init_done) - __zram_reset_device(zram); - up_write(&zram->init_lock); - - return len; -} - -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", - zram_stat64_read(zram, &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", - zram_stat64_read(zram, &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", - zram_stat64_read(zram, &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", - zram_stat64_read(zram, &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", - zram_stat64_read(zram, &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); - - if (zram->init_done) { - val = xv_get_total_size_bytes(zram->mem_pool) + - ((u64)(zram->stats.pages_expand) << PAGE_SHIFT); - } - - return sprintf(buf, "%llu\n", val); -} - -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, -}; - -struct attribute_group zram_disk_attr_group = { - .attrs = zram_disk_attrs, -}; |