diff mbox series

[v2,11/14] ufs: replace ll_rw_block()

Message ID 20220901133505.2510834-12-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, 1:35 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 ufs.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
---
 fs/ufs/balloc.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

Comments

Jan Kara Sept. 1, 2022, 3:59 p.m. UTC | #1
On Thu 01-09-22 21:35:02, 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 ufs.
> 
> 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/ufs/balloc.c | 12 ++++--------
>  1 file changed, 4 insertions(+), 8 deletions(-)
> 
> diff --git a/fs/ufs/balloc.c b/fs/ufs/balloc.c
> index bd810d8239f2..2436e3f82147 100644
> --- a/fs/ufs/balloc.c
> +++ b/fs/ufs/balloc.c
> @@ -295,14 +295,10 @@ static void ufs_change_blocknr(struct inode *inode, sector_t beg,
>  
>  			if (!buffer_mapped(bh))
>  					map_bh(bh, inode->i_sb, oldb + pos);
> -			if (!buffer_uptodate(bh)) {
> -				ll_rw_block(REQ_OP_READ, 1, &bh);
> -				wait_on_buffer(bh);
> -				if (!buffer_uptodate(bh)) {
> -					ufs_error(inode->i_sb, __func__,
> -						  "read of block failed\n");
> -					break;
> -				}
> +			if (bh_read(bh, 0) < 0) {
> +				ufs_error(inode->i_sb, __func__,
> +					  "read of block failed\n");
> +				break;
>  			}
>  
>  			UFSD(" change from %llu to %llu, pos %u\n",
> -- 
> 2.31.1
>
Christoph Hellwig Sept. 5, 2022, 5:56 a.m. UTC | #2
Looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>
diff mbox series

Patch

diff --git a/fs/ufs/balloc.c b/fs/ufs/balloc.c
index bd810d8239f2..2436e3f82147 100644
--- a/fs/ufs/balloc.c
+++ b/fs/ufs/balloc.c
@@ -295,14 +295,10 @@  static void ufs_change_blocknr(struct inode *inode, sector_t beg,
 
 			if (!buffer_mapped(bh))
 					map_bh(bh, inode->i_sb, oldb + pos);
-			if (!buffer_uptodate(bh)) {
-				ll_rw_block(REQ_OP_READ, 1, &bh);
-				wait_on_buffer(bh);
-				if (!buffer_uptodate(bh)) {
-					ufs_error(inode->i_sb, __func__,
-						  "read of block failed\n");
-					break;
-				}
+			if (bh_read(bh, 0) < 0) {
+				ufs_error(inode->i_sb, __func__,
+					  "read of block failed\n");
+				break;
 			}
 
 			UFSD(" change from %llu to %llu, pos %u\n",