From: Junxiao Bi junxiao.bi@oracle.com
[ Upstream commit 70306d9dce75abde855cefaf32b3f71eed8602a3 ]
For sync io read in ocfs2_read_blocks_sync(), first clear bh uptodate flag and submit the io, second wait io done, last check whether bh uptodate, if not return io error.
If two sync io for the same bh were issued, it could be the first io done and set uptodate flag, but just before check that flag, the second io came in and cleared uptodate, then ocfs2_read_blocks_sync() for the first io will return IO error.
Indeed it's not necessary to clear uptodate flag, as the io end handler end_buffer_read_sync() will set or clear it based on io succeed or failed.
The following message was found from a nfs server but the underlying storage returned no error.
[4106438.567376] (nfsd,7146,3):ocfs2_get_suballoc_slot_bit:2780 ERROR: read block 1238823695 failed -5 [4106438.567569] (nfsd,7146,3):ocfs2_get_suballoc_slot_bit:2812 ERROR: status = -5 [4106438.567611] (nfsd,7146,3):ocfs2_test_inode_bit:2894 ERROR: get alloc slot and bit failed -5 [4106438.567643] (nfsd,7146,3):ocfs2_test_inode_bit:2932 ERROR: status = -5 [4106438.567675] (nfsd,7146,3):ocfs2_get_dentry:94 ERROR: test inode bit failed -5
Same issue in non sync read ocfs2_read_blocks(), fixed it as well.
Link: http://lkml.kernel.org/r/20181121020023.3034-4-junxiao.bi@oracle.com Signed-off-by: Junxiao Bi junxiao.bi@oracle.com Reviewed-by: Changwei Ge ge.changwei@h3c.com Reviewed-by: Yiwen Jiang jiangyiwen@huawei.com Cc: Joel Becker jlbec@evilplan.org Cc: Joseph Qi jiangqi903@gmail.com Cc: Jun Piao piaojun@huawei.com Cc: Mark Fasheh mfasheh@versity.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/ocfs2/buffer_head_io.c | 2 -- 1 file changed, 2 deletions(-)
diff --git a/fs/ocfs2/buffer_head_io.c b/fs/ocfs2/buffer_head_io.c index 4ebbd57cbf84..f9b84f7a3e4b 100644 --- a/fs/ocfs2/buffer_head_io.c +++ b/fs/ocfs2/buffer_head_io.c @@ -161,7 +161,6 @@ int ocfs2_read_blocks_sync(struct ocfs2_super *osb, u64 block, #endif }
- clear_buffer_uptodate(bh); get_bh(bh); /* for end_buffer_read_sync() */ bh->b_end_io = end_buffer_read_sync; submit_bh(REQ_OP_READ, 0, bh); @@ -341,7 +340,6 @@ int ocfs2_read_blocks(struct ocfs2_caching_info *ci, u64 block, int nr, continue; }
- clear_buffer_uptodate(bh); get_bh(bh); /* for end_buffer_read_sync() */ if (validate) set_buffer_needs_validate(bh);