[PATCH 09/14] reiserfs: replace ll_rw_block()

From: Zhang Yi
Date: Wed Aug 31 2022 - 03:13:07 EST


ll_rw_block() is not safe for the sync read/write path because it cannot
guarantee that submitting read/write IO if the buffer has been locked.
We could get false positive EIO after wait_on_buffer() in read path if
the buffer has been locked by others. So stop using ll_rw_block() in
reiserfs. We also switch to new bh_readahead_batch() helper for the
buffer array readahead path.

Signed-off-by: Zhang Yi <yi.zhang@xxxxxxxxxx>
---
fs/reiserfs/journal.c | 11 ++++++-----
fs/reiserfs/stree.c | 4 ++--
fs/reiserfs/super.c | 4 +---
3 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/fs/reiserfs/journal.c b/fs/reiserfs/journal.c
index 94addfcefede..699b1b8d5b73 100644
--- a/fs/reiserfs/journal.c
+++ b/fs/reiserfs/journal.c
@@ -868,7 +868,7 @@ static int write_ordered_buffers(spinlock_t * lock,
*/
if (buffer_dirty(bh) && unlikely(bh->b_page->mapping == NULL)) {
spin_unlock(lock);
- ll_rw_block(REQ_OP_WRITE, 1, &bh);
+ write_dirty_buffer(bh, 0);
spin_lock(lock);
}
put_bh(bh);
@@ -1054,7 +1054,7 @@ static int flush_commit_list(struct super_block *s,
if (tbh) {
if (buffer_dirty(tbh)) {
depth = reiserfs_write_unlock_nested(s);
- ll_rw_block(REQ_OP_WRITE, 1, &tbh);
+ write_dirty_buffer(tbh, 0);
reiserfs_write_lock_nested(s, depth);
}
put_bh(tbh) ;
@@ -2240,7 +2240,7 @@ static int journal_read_transaction(struct super_block *sb,
}
}
/* read in the log blocks, memcpy to the corresponding real block */
- ll_rw_block(REQ_OP_READ, get_desc_trans_len(desc), log_blocks);
+ bh_read_batch(log_blocks, get_desc_trans_len(desc));
for (i = 0; i < get_desc_trans_len(desc); i++) {

wait_on_buffer(log_blocks[i]);
@@ -2342,10 +2342,11 @@ static struct buffer_head *reiserfs_breada(struct block_device *dev,
} else
bhlist[j++] = bh;
}
- ll_rw_block(REQ_OP_READ, j, bhlist);
+ bh = bhlist[0];
+ bh_read_nowait(bh, 0);
+ bh_readahead_batch(&bhlist[1], j - 1, 0);
for (i = 1; i < j; i++)
brelse(bhlist[i]);
- bh = bhlist[0];
wait_on_buffer(bh);
if (buffer_uptodate(bh))
return bh;
diff --git a/fs/reiserfs/stree.c b/fs/reiserfs/stree.c
index 9a293609a022..84c12a1947b2 100644
--- a/fs/reiserfs/stree.c
+++ b/fs/reiserfs/stree.c
@@ -579,7 +579,7 @@ static int search_by_key_reada(struct super_block *s,
if (!buffer_uptodate(bh[j])) {
if (depth == -1)
depth = reiserfs_write_unlock_nested(s);
- ll_rw_block(REQ_OP_READ | REQ_RAHEAD, 1, bh + j);
+ bh_readahead(bh[j], REQ_RAHEAD);
}
brelse(bh[j]);
}
@@ -685,7 +685,7 @@ int search_by_key(struct super_block *sb, const struct cpu_key *key,
if (!buffer_uptodate(bh) && depth == -1)
depth = reiserfs_write_unlock_nested(sb);

- ll_rw_block(REQ_OP_READ, 1, &bh);
+ bh_read_nowait(bh, 0);
wait_on_buffer(bh);

if (depth != -1)
diff --git a/fs/reiserfs/super.c b/fs/reiserfs/super.c
index c88cd2ce0665..8b1db82b6949 100644
--- a/fs/reiserfs/super.c
+++ b/fs/reiserfs/super.c
@@ -1702,9 +1702,7 @@ static int read_super_block(struct super_block *s, int offset)
/* after journal replay, reread all bitmap and super blocks */
static int reread_meta_blocks(struct super_block *s)
{
- ll_rw_block(REQ_OP_READ, 1, &SB_BUFFER_WITH_SB(s));
- wait_on_buffer(SB_BUFFER_WITH_SB(s));
- if (!buffer_uptodate(SB_BUFFER_WITH_SB(s))) {
+ if (bh_read(SB_BUFFER_WITH_SB(s), 0)) {
reiserfs_warning(s, "reiserfs-2504", "error reading the super");
return 1;
}
--
2.31.1