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BACKPORT: f2fs: fix to invalidate META_MAPPING before DIO write

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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.

Bug: 243874214

Fixes: 6aa58d8ad2 ("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>
Signed-off-by: Chao Yu <chao@kernel.org>
(cherry picked from commit 67ca06872eb02944b4c6f92cffa9242e92c63109)
Change-Id: Icbfb0a0004172a0af9ab59ffabf92ee7c5f16791
This commit is contained in:
Chao Yu
2022-08-31 14:13:36 +08:00
parent 2301307412
commit fa0cdb5b9d
1 changed files with 5 additions and 2 deletions
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7
fs/f2fs/data.c
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@@ -1490,9 +1490,12 @@ int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map,
*map->m_next_extent = pgofs + map->m_len;
/* for hardware encryption, but to avoid potential issue in future */
if (flag == F2FS_GET_BLOCK_DIO)
if (flag == F2FS_GET_BLOCK_DIO) {
f2fs_wait_on_block_writeback_range(inode,
map->m_pblk, map->m_len);
invalidate_mapping_pages(META_MAPPING(sbi),
map->m_pblk, map->m_pblk + map->m_len - 1);
}
goto out;
}
@@ -1673,7 +1676,7 @@ sync_out:
f2fs_wait_on_block_writeback_range(inode,
map->m_pblk, map->m_len);
invalidate_mapping_pages(META_MAPPING(sbi),
map->m_pblk, map->m_pblk);
map->m_pblk, map->m_pblk + map->m_len - 1);
}
if (flag == F2FS_GET_BLOCK_PRECACHE) {