diff mbox series

[v2,08/14] ocfs2: replace ll_rw_block()

Message ID 20220901133505.2510834-9-yi.zhang@huawei.com (mailing list archive)
State New, archived
Headers show
Series fs/buffer: remove ll_rw_block() | expand

Commit Message

Zhang Yi Sept. 1, 2022, 1:34 p.m. UTC
ll_rw_block() is not safe for the sync read path because it cannot
guarantee that submitting read IO if the buffer has been locked. We
could get false positive EIO after wait_on_buffer() if the buffer has
been locked by others. So stop using ll_rw_block() in ocfs2.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
---
 fs/ocfs2/aops.c  | 2 +-
 fs/ocfs2/super.c | 4 +---
 2 files changed, 2 insertions(+), 4 deletions(-)

Comments

Jan Kara Sept. 1, 2022, 3:51 p.m. UTC | #1
On Thu 01-09-22 21:34:59, Zhang Yi wrote:
> ll_rw_block() is not safe for the sync read path because it cannot
> guarantee that submitting read IO if the buffer has been locked. We
> could get false positive EIO after wait_on_buffer() if the buffer has
> been locked by others. So stop using ll_rw_block() in ocfs2.
> 
> Signed-off-by: Zhang Yi <yi.zhang@huawei.com>

Looks good to me. Feel free to add:

Reviewed-by: Jan Kara <jack@suse.cz>

								Honza

> ---
>  fs/ocfs2/aops.c  | 2 +-
>  fs/ocfs2/super.c | 4 +---
>  2 files changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
> index af4157f61927..1d65f6ef00ca 100644
> --- a/fs/ocfs2/aops.c
> +++ b/fs/ocfs2/aops.c
> @@ -636,7 +636,7 @@ int ocfs2_map_page_blocks(struct page *page, u64 *p_blkno,
>  			   !buffer_new(bh) &&
>  			   ocfs2_should_read_blk(inode, page, block_start) &&
>  			   (block_start < from || block_end > to)) {
> -			ll_rw_block(REQ_OP_READ, 1, &bh);
> +			bh_read_nowait(bh, 0);
>  			*wait_bh++=bh;
>  		}
>  
> diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
> index e2cc9eec287c..26b4c2bfee49 100644
> --- a/fs/ocfs2/super.c
> +++ b/fs/ocfs2/super.c
> @@ -1764,9 +1764,7 @@ static int ocfs2_get_sector(struct super_block *sb,
>  	if (!buffer_dirty(*bh))
>  		clear_buffer_uptodate(*bh);
>  	unlock_buffer(*bh);
> -	ll_rw_block(REQ_OP_READ, 1, bh);
> -	wait_on_buffer(*bh);
> -	if (!buffer_uptodate(*bh)) {
> +	if (bh_read(*bh, 0) < 0) {
>  		mlog_errno(-EIO);
>  		brelse(*bh);
>  		*bh = NULL;
> -- 
> 2.31.1
>
Christoph Hellwig Sept. 5, 2022, 5:55 a.m. UTC | #2
Looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>
Joseph Qi Sept. 6, 2022, 1:06 a.m. UTC | #3
On 9/1/22 9:34 PM, Zhang Yi via Ocfs2-devel wrote:
> ll_rw_block() is not safe for the sync read path because it cannot
> guarantee that submitting read IO if the buffer has been locked. We
> could get false positive EIO after wait_on_buffer() if the buffer has
> been locked by others. So stop using ll_rw_block() in ocfs2.
> 
> Signed-off-by: Zhang Yi <yi.zhang@huawei.com>

Looks good to me.
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>

> ---
>  fs/ocfs2/aops.c  | 2 +-
>  fs/ocfs2/super.c | 4 +---
>  2 files changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
> index af4157f61927..1d65f6ef00ca 100644
> --- a/fs/ocfs2/aops.c
> +++ b/fs/ocfs2/aops.c
> @@ -636,7 +636,7 @@ int ocfs2_map_page_blocks(struct page *page, u64 *p_blkno,
>  			   !buffer_new(bh) &&
>  			   ocfs2_should_read_blk(inode, page, block_start) &&
>  			   (block_start < from || block_end > to)) {
> -			ll_rw_block(REQ_OP_READ, 1, &bh);
> +			bh_read_nowait(bh, 0);
>  			*wait_bh++=bh;
>  		}
>  
> diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
> index e2cc9eec287c..26b4c2bfee49 100644
> --- a/fs/ocfs2/super.c
> +++ b/fs/ocfs2/super.c
> @@ -1764,9 +1764,7 @@ static int ocfs2_get_sector(struct super_block *sb,
>  	if (!buffer_dirty(*bh))
>  		clear_buffer_uptodate(*bh);
>  	unlock_buffer(*bh);
> -	ll_rw_block(REQ_OP_READ, 1, bh);
> -	wait_on_buffer(*bh);
> -	if (!buffer_uptodate(*bh)) {
> +	if (bh_read(*bh, 0) < 0) {
>  		mlog_errno(-EIO);
>  		brelse(*bh);
>  		*bh = NULL;
diff mbox series

Patch

diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index af4157f61927..1d65f6ef00ca 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -636,7 +636,7 @@  int ocfs2_map_page_blocks(struct page *page, u64 *p_blkno,
 			   !buffer_new(bh) &&
 			   ocfs2_should_read_blk(inode, page, block_start) &&
 			   (block_start < from || block_end > to)) {
-			ll_rw_block(REQ_OP_READ, 1, &bh);
+			bh_read_nowait(bh, 0);
 			*wait_bh++=bh;
 		}
 
diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index e2cc9eec287c..26b4c2bfee49 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -1764,9 +1764,7 @@  static int ocfs2_get_sector(struct super_block *sb,
 	if (!buffer_dirty(*bh))
 		clear_buffer_uptodate(*bh);
 	unlock_buffer(*bh);
-	ll_rw_block(REQ_OP_READ, 1, bh);
-	wait_on_buffer(*bh);
-	if (!buffer_uptodate(*bh)) {
+	if (bh_read(*bh, 0) < 0) {
 		mlog_errno(-EIO);
 		brelse(*bh);
 		*bh = NULL;