f2fs: support passing down write hints given by users to block layer
Add the 'whint_mode' mount option that controls which write
hints are passed down to block layer. There are "off" and
"user-based" mode. The default mode is "off".
1) whint_mode=off. F2FS only passes down WRITE_LIFE_NOT_SET.
2) whint_mode=user-based. F2FS tries to pass down hints given
by users.
User F2FS Block
---- ---- -----
META WRITE_LIFE_NOT_SET
HOT_NODE "
WARM_NODE "
COLD_NODE "
ioctl(COLD) COLD_DATA WRITE_LIFE_EXTREME
extension list " "
-- buffered io
WRITE_LIFE_EXTREME COLD_DATA WRITE_LIFE_EXTREME
WRITE_LIFE_SHORT HOT_DATA WRITE_LIFE_SHORT
WRITE_LIFE_NOT_SET WARM_DATA WRITE_LIFE_NOT_SET
WRITE_LIFE_NONE " "
WRITE_LIFE_MEDIUM " "
WRITE_LIFE_LONG " "
-- direct io
WRITE_LIFE_EXTREME COLD_DATA WRITE_LIFE_EXTREME
WRITE_LIFE_SHORT HOT_DATA WRITE_LIFE_SHORT
WRITE_LIFE_NOT_SET WARM_DATA WRITE_LIFE_NOT_SET
WRITE_LIFE_NONE " WRITE_LIFE_NONE
WRITE_LIFE_MEDIUM " WRITE_LIFE_MEDIUM
WRITE_LIFE_LONG " WRITE_LIFE_LONG
Many thanks to Chao Yu and Jaegeuk Kim for comments to
implement this patch.
Signed-off-by: Hyunchul Lee <cheol.lee@lge.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
[Jaegeuk Kim: avoid build warning]
[Chao Yu: fix to restore whint_mode in ->remount_fs]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
7 files changed