udf: replace ll_rw_block()

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(). We also switch to
new bh_readahead_batch() helper for the buffer array readahead path.

Link: https://lkml.kernel.org/r/20220901133505.2510834-11-yi.zhang@huawei.com
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Zhang Yi 2022-09-01 21:35:01 +08:00 committed by Andrew Morton
parent d554822e82
commit 59a16786fa
3 changed files with 3 additions and 9 deletions

View File

@ -130,7 +130,7 @@ static int udf_readdir(struct file *file, struct dir_context *ctx)
brelse(tmp);
}
if (num) {
ll_rw_block(REQ_OP_READ | REQ_RAHEAD, num, bha);
bh_readahead_batch(num, bha, REQ_RAHEAD);
for (i = 0; i < num; i++)
brelse(bha[i]);
}

View File

@ -89,7 +89,7 @@ struct fileIdentDesc *udf_fileident_read(struct inode *dir, loff_t *nf_pos,
brelse(tmp);
}
if (num) {
ll_rw_block(REQ_OP_READ | REQ_RAHEAD, num, bha);
bh_readahead_batch(num, bha, REQ_RAHEAD);
for (i = 0; i < num; i++)
brelse(bha[i]);
}

View File

@ -1211,13 +1211,7 @@ struct buffer_head *udf_bread(struct inode *inode, udf_pblk_t block,
if (!bh)
return NULL;
if (buffer_uptodate(bh))
return bh;
ll_rw_block(REQ_OP_READ, 1, &bh);
wait_on_buffer(bh);
if (buffer_uptodate(bh))
if (bh_read(bh, 0) >= 0)
return bh;
brelse(bh);