btrfs: pass a valid btrfs_tree_parent_check when possible

Commit 6e181cfe2409 ("btrfs: revalidate cached tree blocks on the
uptodate path") introduced the @check parameter for
btrfs_buffer_uptodate() to allow re-validation of a cached extent
buffer.

But there are still call sites that don't utilize this parameter, which
exposes them to possible corrupted tree blocks, e.g. an empty child leaf
of a parent node, which should be rejected by btrfs_verify_level_key()
but if @check is NULL such check will be skipped and cause problems.

Thankfully for a lot of cases there is already an existing @check
structure around and we can pass it directly to btrfs_buffer_uptodate().

Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index d70da290bedfc7c8286c339080d5db41e2616dd0..829d8be7f423b5091cec8656e324090d98b4c01d 100644 (file)
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -1497,17 +1497,11 @@ read_block_for_search(struct btrfs_root *root, struct btrfs_path *p,
                if (p->reada == READA_FORWARD_ALWAYS)
                        reada_for_search(fs_info, p, parent_level, slot, key->objectid);
 
-               /* first we do an atomic uptodate check */
-               if (btrfs_buffer_uptodate(tmp, check.transid, NULL) > 0) {
-                       /*
-                        * Do extra check for first_key, eb can be stale due to
-                        * being cached, read from scrub, or have multiple
-                        * parents (shared tree blocks).
-                        */
-                       if (unlikely(btrfs_verify_level_key(tmp, &check))) {
-                               ret = -EUCLEAN;
-                               goto out;
-                       }
+               /* Check if the cached eb is uptodate. */
+               ret = btrfs_buffer_uptodate(tmp, check.transid, &check);
+               if (unlikely(ret < 0))
+                       goto out;
+               if (ret > 0) {
                        *eb_ret = tmp;
                        tmp = NULL;
                        ret = 0;

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 391fad41c3b6d98ab7468a5b7b0003f692871407..5d5b42ea4adef7a901a318ccb0cf6857cf9c3df1 100644 (file)
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -5781,16 +5781,21 @@ static int check_next_block_uptodate(struct btrfs_trans_handle *trans,
 
        generation = btrfs_node_ptr_generation(path->nodes[level], path->slots[level]);
 
-       if (btrfs_buffer_uptodate(next, generation, NULL))
-               return 0;
-
        check.level = level - 1;
        check.transid = generation;
        check.owner_root = btrfs_root_id(root);
        check.has_first_key = true;
        btrfs_node_key_to_cpu(path->nodes[level], &check.first_key, path->slots[level]);
 
+       ret = btrfs_buffer_uptodate(next, generation, &check);
+       if (ret > 0)
+               return 0;
        btrfs_tree_unlock(next);
+       if (ret < 0) {
+               free_extent_buffer(next);
+               return ret;
+       }
+
        if (level == 1)
                reada_walk_down(trans, root, wc, path);
        ret = btrfs_read_extent_buffer(next, &check);

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 2275189b78605560ee247e51b62f82ec2074e27f..8aa9e1a88155011f3f865e38463968aa28a1525d 100644 (file)
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -4660,7 +4660,7 @@ void btrfs_readahead_tree_block(struct btrfs_fs_info *fs_info,
        if (IS_ERR(eb))
                return;
 
-       if (btrfs_buffer_uptodate(eb, gen, NULL)) {
+       if (btrfs_buffer_uptodate(eb, gen, &check)) {
                free_extent_buffer(eb);
                return;
        }