[Ocfs2-devel] [PATCH] ocfs2: don't clear bh uptodate for sync read
Changwei Ge
ge.changwei at h3c.com
Tue Nov 13 03:04:27 PST 2018
Hi Junxiao,
Do we have the same problem in ocfs2_read_blocks()?
Thanks,
Changwei
On 2018/11/13 13:00, Junxiao Bi wrote:
> 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
>
> Signed-off-by: Junxiao Bi <junxiao.bi at oracle.com>
> ---
> fs/ocfs2/buffer_head_io.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/fs/ocfs2/buffer_head_io.c b/fs/ocfs2/buffer_head_io.c
> index 4ebbd57cbf84..45ee47a3c91b 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);
>
More information about the Ocfs2-devel
mailing list