leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

zram: break the strict dependency from lzo

Browse Source 
From the beginning, the zram block device always enabled CRYPTO_LZO,
since lzo-rle is hardcoded as the fallback compression algorithm.  As a
consequence, on systems where another compression algorithm is chosen
(e.g.  CRYPTO_ZSTD), the lzo kernel module becomes unused, while still
having to be built/loaded.

This patch removes the hardcoded lzo-rle dependency and allows the user
to select the default compression algorithm for zram at build time.  The
previous behaviour is kept, as the default algorithm is still lzo-rle.

Link: https://lkml.kernel.org/r/20201207121245.50529-1-rsalvaterra@gmail.com
Signed-off-by: Rui Salvaterra <rsalvaterra@gmail.com>
Suggested-by: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Suggested-by: Minchan Kim <minchan@kernel.org>
Acked-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Rui Salvaterra 2020-12-14 19:14:35 -08:00 committed by Linus Torvalds
parent 194e28da1a
commit 3d711a3827
3 changed files with 44 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

42
drivers/block/zram/Kconfig
View File

@ -2,7 +2,7 @@
config ZRAM
tristate "Compressed RAM block device support"
depends on BLOCK && SYSFS && ZSMALLOC && CRYPTO
select CRYPTO_LZO
depends on CRYPTO_LZO || CRYPTO_ZSTD || CRYPTO_LZ4 || CRYPTO_LZ4HC || CRYPTO_842
help
Creates virtual block devices called /dev/zramX (X = 0, 1, ...).
Pages written to these disks are compressed and stored in memory
@ -14,6 +14,46 @@ config ZRAM
See Documentation/admin-guide/blockdev/zram.rst for more information.
choice
prompt "Default zram compressor"
default ZRAM_DEF_COMP_LZORLE
depends on ZRAM
config ZRAM_DEF_COMP_LZORLE
bool "lzo-rle"
depends on CRYPTO_LZO
config ZRAM_DEF_COMP_ZSTD
bool "zstd"
depends on CRYPTO_ZSTD
config ZRAM_DEF_COMP_LZ4
bool "lz4"
depends on CRYPTO_LZ4
config ZRAM_DEF_COMP_LZO
bool "lzo"
depends on CRYPTO_LZO
config ZRAM_DEF_COMP_LZ4HC
bool "lz4hc"
depends on CRYPTO_LZ4HC
config ZRAM_DEF_COMP_842
bool "842"
depends on CRYPTO_842
endchoice
config ZRAM_DEF_COMP
string
default "lzo-rle" if ZRAM_DEF_COMP_LZORLE
default "zstd" if ZRAM_DEF_COMP_ZSTD
default "lz4" if ZRAM_DEF_COMP_LZ4
default "lzo" if ZRAM_DEF_COMP_LZO
default "lz4hc" if ZRAM_DEF_COMP_LZ4HC
default "842" if ZRAM_DEF_COMP_842
config ZRAM_WRITEBACK
bool "Write back incompressible or idle page to backing device"
depends on ZRAM

2
drivers/block/zram/zcomp.c
View File

@ -15,8 +15,10 @@
#include "zcomp.h"
static const char * const backends[] = {
#if IS_ENABLED(CONFIG_CRYPTO_LZO)
"lzo",
"lzo-rle",
#endif
#if IS_ENABLED(CONFIG_CRYPTO_LZ4)
"lz4",
#endif

2
drivers/block/zram/zram_drv.c
View File

@ -42,7 +42,7 @@ static DEFINE_IDR(zram_index_idr);
static DEFINE_MUTEX(zram_index_mutex);
static int zram_major;
static const char *default_compressor = "lzo-rle";
static const char *default_compressor = CONFIG_ZRAM_DEF_COMP;
/* Module params (documentation at end) */
static unsigned int num_devices = 1;