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author | Chao Yu <chao@kernel.org> | 2022-07-06 09:30:15 +0300 |
---|---|---|
committer | Jaegeuk Kim <jaegeuk@kernel.org> | 2022-07-31 06:16:20 +0300 |
commit | 67ca06872eb02944b4c6f92cffa9242e92c63109 (patch) | |
tree | 1480df337ba642e4cffcbbcbddf3f9d429c9bae8 /tools/perf/scripts/python/export-to-postgresql.py | |
parent | 8e0f54a70e9b0c88d6375933d281d631b7248153 (diff) | |
download | linux-67ca06872eb02944b4c6f92cffa9242e92c63109.tar.xz |
f2fs: fix to invalidate META_MAPPING before DIO write
Quoted from commit e3b49ea36802 ("f2fs: invalidate META_MAPPING before
IPU/DIO write")
"
Encrypted pages during GC are read and cached in META_MAPPING.
However, due to cached pages in META_MAPPING, there is an issue where
newly written pages are lost by IPU or DIO writes.
Thread A - f2fs_gc() Thread B
/* phase 3 */
down_write(i_gc_rwsem)
ra_data_block() ---- (a)
up_write(i_gc_rwsem)
f2fs_direct_IO() :
- down_read(i_gc_rwsem)
- __blockdev_direct_io()
- get_data_block_dio_write()
- f2fs_dio_submit_bio() ---- (b)
- up_read(i_gc_rwsem)
/* phase 4 */
down_write(i_gc_rwsem)
move_data_block() ---- (c)
up_write(i_gc_rwsem)
(a) In phase 3 of f2fs_gc(), up-to-date page is read from storage and
cached in META_MAPPING.
(b) In thread B, writing new data by IPU or DIO write on same blkaddr as
read in (a). cached page in META_MAPPING become out-dated.
(c) In phase 4 of f2fs_gc(), out-dated page in META_MAPPING is copied to
new blkaddr. In conclusion, the newly written data in (b) is lost.
To address this issue, invalidating pages in META_MAPPING before IPU or
DIO write.
"
In previous commit, we missed to cover extent cache hit case, and passed
wrong value for parameter @end of invalidate_mapping_pages(), fix both
issues.
Fixes: 6aa58d8ad20a ("f2fs: readahead encrypted block during GC")
Fixes: e3b49ea36802 ("f2fs: invalidate META_MAPPING before IPU/DIO write")
Cc: Hyeong-Jun Kim <hj514.kim@samsung.com>
Signed-off-by: Chao Yu <chao.yu@oppo.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Diffstat (limited to 'tools/perf/scripts/python/export-to-postgresql.py')
0 files changed, 0 insertions, 0 deletions