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

Jan Kara
2022-09-01T15:59:14Z

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
>
--
Jan Kara <jack@suse.com>
SUSE Labs, CR