From: zhengliang zhengliang6@huawei.com
[ Upstream commit a0770e13c8da83bdb64738c0209ab02dd3cfff8b ]
v4: Rearrange the previous three versions.
The following scenario could lead to data block override by mistake.
TASK A | TASK kworker | TASK B | TASK C | | | open | | | write | | | close | | | | f2fs_write_data_pages | | | f2fs_write_cache_pages | | | f2fs_outplace_write_data | | | f2fs_allocate_data_block (get block in seg S, | | | S is full, and only | | | have this valid data | | | block) | | | allocate_segment | | | locate_dirty_segment (mark S as PRE) | | | f2fs_submit_page_write (submit but is not | | | written on dev) | | unlink | | | iput_final | | | f2fs_drop_inode | | | f2fs_truncate | | | (not evict) | | | | | write_checkpoint | | | flush merged bio but not wait file data writeback | | | set_prefree_as_free (mark S as FREE) | | | | update NODE/DATA | | | allocate_segment (select S) | writeback done | |
So we need to guarantee io complete before truncate inode in f2fs_drop_inode.
Reviewed-by: Chao Yu yuchao0@huawei.com Signed-off-by: Zheng Liang zhengliang6@huawei.com Signed-off-by: Jaegeuk Kim jaegeuk@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/f2fs/super.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index 0f3209b23c940..331f16a7c676f 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -668,6 +668,10 @@ static int f2fs_drop_inode(struct inode *inode) sb_start_intwrite(inode->i_sb); f2fs_i_size_write(inode, 0);
+ f2fs_submit_merged_write_cond(F2FS_I_SB(inode), + inode, NULL, 0, DATA); + truncate_inode_pages_final(inode->i_mapping); + if (F2FS_HAS_BLOCKS(inode)) f2fs_truncate(inode);