staging: zram: replace xvmalloc with zsmalloc

Replaces xvmalloc with zsmalloc as the compressed page allocator
for zram

Signed-off-by: Nitin Gupta <ngupta@vflare.org>
Acked-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Nitin Gupta 2012-01-09 16:51:59 -06:00 committed by Greg Kroah-Hartman
parent 94add674a7
commit fd1a30dea1
5 changed files with 46 additions and 62 deletions

View file

@ -1,11 +1,7 @@
config XVMALLOC
bool
default n
config ZRAM
tristate "Compressed RAM block device support"
depends on BLOCK && SYSFS
select XVMALLOC
select ZSMALLOC
select LZO_COMPRESS
select LZO_DECOMPRESS
default n

View file

@ -1,4 +1,3 @@
zram-y := zram_drv.o zram_sysfs.o
obj-$(CONFIG_ZRAM) += zram.o
obj-$(CONFIG_XVMALLOC) += xvmalloc.o

View file

@ -135,13 +135,9 @@ static void zram_set_disksize(struct zram *zram, size_t totalram_bytes)
static void zram_free_page(struct zram *zram, size_t index)
{
u32 clen;
void *obj;
void *handle = zram->table[index].handle;
struct page *page = zram->table[index].page;
u32 offset = zram->table[index].offset;
if (unlikely(!page)) {
if (unlikely(!handle)) {
/*
* No memory is allocated for zero filled pages.
* Simply clear zero page flag.
@ -154,27 +150,24 @@ static void zram_free_page(struct zram *zram, size_t index)
}
if (unlikely(zram_test_flag(zram, index, ZRAM_UNCOMPRESSED))) {
clen = PAGE_SIZE;
__free_page(page);
__free_page(handle);
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);
zs_free(zram->mem_pool, handle);
xv_free(zram->mem_pool, page, offset);
if (clen <= PAGE_SIZE / 2)
if (zram->table[index].size <= PAGE_SIZE / 2)
zram_stat_dec(&zram->stats.good_compress);
out:
zram_stat64_sub(zram, &zram->stats.compr_size, clen);
zram_stat64_sub(zram, &zram->stats.compr_size,
zram->table[index].size);
zram_stat_dec(&zram->stats.pages_stored);
zram->table[index].page = NULL;
zram->table[index].offset = 0;
zram->table[index].handle = NULL;
zram->table[index].size = 0;
}
static void handle_zero_page(struct bio_vec *bvec)
@ -196,7 +189,7 @@ static void handle_uncompressed_page(struct zram *zram, struct bio_vec *bvec,
unsigned char *user_mem, *cmem;
user_mem = kmap_atomic(page, KM_USER0);
cmem = kmap_atomic(zram->table[index].page, KM_USER1);
cmem = kmap_atomic(zram->table[index].handle, KM_USER1);
memcpy(user_mem + bvec->bv_offset, cmem + offset, bvec->bv_len);
kunmap_atomic(cmem, KM_USER1);
@ -227,7 +220,7 @@ static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec,
}
/* Requested page is not present in compressed area */
if (unlikely(!zram->table[index].page)) {
if (unlikely(!zram->table[index].handle)) {
pr_debug("Read before write: sector=%lu, size=%u",
(ulong)(bio->bi_sector), bio->bi_size);
handle_zero_page(bvec);
@ -254,11 +247,10 @@ static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec,
uncmem = user_mem;
clen = PAGE_SIZE;
cmem = kmap_atomic(zram->table[index].page, KM_USER1) +
zram->table[index].offset;
cmem = zs_map_object(zram->mem_pool, zram->table[index].handle);
ret = lzo1x_decompress_safe(cmem + sizeof(*zheader),
xv_get_object_size(cmem) - sizeof(*zheader),
zram->table[index].size,
uncmem, &clen);
if (is_partial_io(bvec)) {
@ -267,7 +259,7 @@ static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec,
kfree(uncmem);
}
kunmap_atomic(cmem, KM_USER1);
zs_unmap_object(zram->mem_pool, zram->table[index].handle);
kunmap_atomic(user_mem, KM_USER0);
/* Should NEVER happen. Return bio error if it does. */
@ -290,13 +282,12 @@ static int zram_read_before_write(struct zram *zram, char *mem, u32 index)
unsigned char *cmem;
if (zram_test_flag(zram, index, ZRAM_ZERO) ||
!zram->table[index].page) {
!zram->table[index].handle) {
memset(mem, 0, PAGE_SIZE);
return 0;
}
cmem = kmap_atomic(zram->table[index].page, KM_USER0) +
zram->table[index].offset;
cmem = zs_map_object(zram->mem_pool, zram->table[index].handle);
/* Page is stored uncompressed since it's incompressible */
if (unlikely(zram_test_flag(zram, index, ZRAM_UNCOMPRESSED))) {
@ -306,9 +297,9 @@ static int zram_read_before_write(struct zram *zram, char *mem, u32 index)
}
ret = lzo1x_decompress_safe(cmem + sizeof(*zheader),
xv_get_object_size(cmem) - sizeof(*zheader),
zram->table[index].size,
mem, &clen);
kunmap_atomic(cmem, KM_USER0);
zs_unmap_object(zram->mem_pool, zram->table[index].handle);
/* Should NEVER happen. Return bio error if it does. */
if (unlikely(ret != LZO_E_OK)) {
@ -326,6 +317,7 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
int ret;
u32 store_offset;
size_t clen;
void *handle;
struct zobj_header *zheader;
struct page *page, *page_store;
unsigned char *user_mem, *cmem, *src, *uncmem = NULL;
@ -355,7 +347,7 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
* System overwrites unused sectors. Free memory associated
* with this sector now.
*/
if (zram->table[index].page ||
if (zram->table[index].handle ||
zram_test_flag(zram, index, ZRAM_ZERO))
zram_free_page(zram, index);
@ -407,26 +399,22 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
store_offset = 0;
zram_set_flag(zram, index, ZRAM_UNCOMPRESSED);
zram_stat_inc(&zram->stats.pages_expand);
zram->table[index].page = page_store;
handle = page_store;
src = kmap_atomic(page, KM_USER0);
cmem = kmap_atomic(page_store, KM_USER1);
goto memstore;
}
if (xv_malloc(zram->mem_pool, clen + sizeof(*zheader),
&zram->table[index].page, &store_offset,
GFP_NOIO | __GFP_HIGHMEM)) {
handle = zs_malloc(zram->mem_pool, clen + sizeof(*zheader));
if (!handle) {
pr_info("Error allocating memory for compressed "
"page: %u, size=%zu\n", index, clen);
ret = -ENOMEM;
goto out;
}
cmem = zs_map_object(zram->mem_pool, handle);
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)) {
@ -438,9 +426,15 @@ memstore:
memcpy(cmem, src, clen);
kunmap_atomic(cmem, KM_USER1);
if (unlikely(zram_test_flag(zram, index, ZRAM_UNCOMPRESSED)))
if (unlikely(zram_test_flag(zram, index, ZRAM_UNCOMPRESSED))) {
kunmap_atomic(cmem, KM_USER1);
kunmap_atomic(src, KM_USER0);
} else {
zs_unmap_object(zram->mem_pool, handle);
}
zram->table[index].handle = handle;
zram->table[index].size = clen;
/* Update stats */
zram_stat64_add(zram, &zram->stats.compr_size, clen);
@ -598,25 +592,20 @@ void __zram_reset_device(struct zram *zram)
/* 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)
void *handle = zram->table[index].handle;
if (!handle)
continue;
if (unlikely(zram_test_flag(zram, index, ZRAM_UNCOMPRESSED)))
__free_page(page);
__free_page(handle);
else
xv_free(zram->mem_pool, page, offset);
zs_free(zram->mem_pool, handle);
}
vfree(zram->table);
zram->table = NULL;
xv_destroy_pool(zram->mem_pool);
zs_destroy_pool(zram->mem_pool);
zram->mem_pool = NULL;
/* Reset stats */
@ -674,7 +663,7 @@ int zram_init_device(struct zram *zram)
/* zram devices sort of resembles non-rotational disks */
queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zram->disk->queue);
zram->mem_pool = xv_create_pool();
zram->mem_pool = zs_create_pool("zram", GFP_NOIO | __GFP_HIGHMEM);
if (!zram->mem_pool) {
pr_err("Error creating memory pool\n");
ret = -ENOMEM;

View file

@ -18,7 +18,7 @@
#include <linux/spinlock.h>
#include <linux/mutex.h>
#include "xvmalloc.h"
#include "../zsmalloc/zsmalloc.h"
/*
* Some arbitrary value. This is just to catch
@ -51,7 +51,7 @@ 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)
* ZS_MAX_ALLOC_SIZE - sizeof(struct zobj_header)
* otherwise, xv_malloc() would always return failure.
*/
@ -81,8 +81,8 @@ enum zram_pageflags {
/* Allocated for each disk page */
struct table {
struct page *page;
u16 offset;
void *handle;
u16 size; /* object size (excluding header) */
u8 count; /* object ref count (not yet used) */
u8 flags;
} __attribute__((aligned(4)));
@ -102,7 +102,7 @@ struct zram_stats {
};
struct zram {
struct xv_pool *mem_pool;
struct zs_pool *mem_pool;
void *compress_workmem;
void *compress_buffer;
struct table *table;

View file

@ -187,7 +187,7 @@ static ssize_t mem_used_total_show(struct device *dev,
struct zram *zram = dev_to_zram(dev);
if (zram->init_done) {
val = xv_get_total_size_bytes(zram->mem_pool) +
val = zs_get_total_size_bytes(zram->mem_pool) +
((u64)(zram->stats.pages_expand) << PAGE_SHIFT);
}