From: Hyunchul Lee <cheol.lee@xxxxxxx> This set implements passing down write hints to block layer with the following mapping. This mapping equals the conclusion from discussion in the link, https://sourceforge.net/p/linux-f2fs/mailman/message/36170969/ But there are two exceptions. (1) the 'iohint_mode' mount option is changed to 'whint_mode'. (2) in "user-based" mode, WRITE_LIFE_EXTREME is passed down instead of WRITE_LIFE_NOT_SET for files flagged with ioctl(COLD) and extension list. Sorry for late patch. 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 3) whint_mode=fs-based. F2FS passes down hints with its policy. User F2FS Block ---- ---- ----- META WRITE_LIFE_MEDIUM; HOT_NODE WRITE_LIFE_NOT_SET WARM_NODE " COLD_NODE WRITE_LIFE_NONE 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_LONG 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 Hyunchul Lee (3): f2fs: support passing down write hints given by users to block layer f2fs: support passing down write hints to block layer with F2FS policy f2fs: Add the 'whint_mode' mount option to f2fs documentation Documentation/filesystems/f2fs.txt | 6 +++ fs/f2fs/data.c | 27 ++++++++-- fs/f2fs/f2fs.h | 10 ++++ fs/f2fs/segment.c | 104 +++++++++++++++++++++++++++++++++++++ fs/f2fs/super.c | 29 ++++++++++- 5 files changed, 170 insertions(+), 6 deletions(-) -- 1.9.1
