check_fs_roots() will check all fs trees again if fs_info->tree_root
have been cowed.
It is inefficient if there are many subvolumes in filesystem.
And it also causes dead loop while repairing
fuzz-tests/images/bko-161811.raw:
=============================
ERROR: DIR_ITEM[256 1167283096] name namelen 32 filetype 1 mismatch with its hash, wanted 1167283096 have 709597396
invalid location in dir item 0
root 5 root dir 256 error
root 5 inode 256 errors 10, odd dir item
Failed to reset nlink for inode 18446744073709551361: No such file or directory
unresolved ref dir 256 index 0 namelen 32 name filetype 1 errors 106, no dir index, no inode ref, name too long
ERROR: DIR_ITEM[256 1167283096] name namelen 32 filetype 1 mismatch with its hash, wanted 1167283096 have 709597396
invalid location in dir item 0
root 5 root dir 256 error
root 5 inode 256 errors 10, odd dir item
Failed to reset nlink for inode 18446744073709551361: No such file or directory
unresolved ref dir 256 index 0 namelen 32 name filetype 1 errors 106, no dir index, no inode ref, name too long
ERROR: DIR_ITEM[256 1167283096] name namelen 32 filetype 1 mismatch with its hash, wanted 1167283
...
==============================
Process of the dead loop:
1) check_fs_root() failed to repair the inode.
2) btrfs_commit_transaction() did cow of the fs_info->tree_root
3) check_fs_roots() restarted to check fs tree.
4) goto 1).
Introduce a variable @prev_key to record last checked root_item.
If check_fs_root() failed, go to check the next fs_tree instead of
trying it again and again.
Signed-off-by: Su Yue <suy.fnst@xxxxxxxxxxxxxx>
---
cmds-check.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)
diff --git a/cmds-check.c b/cmds-check.c
index 68348ae94c8b..d149608acde2 100644
--- a/cmds-check.c
+++ b/cmds-check.c
@@ -4587,6 +4587,7 @@ static int check_fs_roots(struct btrfs_fs_info *fs_info,
{
struct btrfs_path path;
struct btrfs_key key;
+ struct btrfs_key prev_key;
struct walk_control wc;
struct extent_buffer *leaf, *tree_node;
struct btrfs_root *tmp_root;
@@ -4609,19 +4610,21 @@ static int check_fs_roots(struct btrfs_fs_info *fs_info,
cache_tree_init(&wc.shared);
btrfs_init_path(&path);
+ prev_key.offset = 0;
+ prev_key.objectid = 0;
+ prev_key.type = BTRFS_ROOT_ITEM_KEY;
again:
- key.offset = 0;
- key.objectid = 0;
- key.type = BTRFS_ROOT_ITEM_KEY;
+ key = prev_key;
ret = btrfs_search_slot(NULL, tree_root, &key, &path, 0, 0);
if (ret < 0) {
err = 1;
goto out;
}
+ if (!ret)
+ path.slots[0]++;
tree_node = tree_root->node;
while (1) {
if (tree_node != tree_root->node) {
- free_root_recs_tree(root_cache);
btrfs_release_path(&path);
goto again;
}
@@ -4636,6 +4639,9 @@ again:
leaf = path.nodes[0];
}
btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
+ /* save key */
+ prev_key = key;
+
if (key.type == BTRFS_ROOT_ITEM_KEY &&
fs_root_objectid(key.objectid)) {
if (key.objectid == BTRFS_TREE_RELOC_OBJECTID) {
@@ -4654,6 +4660,8 @@ again:
if (ret == -EAGAIN) {
free_root_recs_tree(root_cache);
btrfs_release_path(&path);
+ prev_key.objectid = 0;
+ prev_key.offset = 0;
goto again;
}
if (ret)
--
2.15.0
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
