Btrfs: new backref walking code
The old backref iteration code could only safely be used on commit roots.
Besides this limitation, it had bugs in finding the roots for these
references. This commit replaces large parts of it by btrfs_find_all_roots()
which a) really finds all roots and the correct roots, b) works correctly
under heavy file system load, c) considers delayed refs.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index c27bcb6..b5edff2 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -309,7 +309,7 @@
u8 ref_level;
unsigned long ptr = 0;
const int bufsize = 4096;
- u64 extent_offset;
+ u64 extent_item_pos;
path = btrfs_alloc_path();
@@ -329,12 +329,13 @@
if (ret < 0)
goto out;
- extent_offset = swarn.logical - found_key.objectid;
+ extent_item_pos = swarn.logical - found_key.objectid;
swarn.extent_item_size = found_key.offset;
eb = path->nodes[0];
ei = btrfs_item_ptr(eb, path->slots[0], struct btrfs_extent_item);
item_size = btrfs_item_size_nr(eb, path->slots[0]);
+ btrfs_release_path(path);
if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
do {
@@ -351,7 +352,7 @@
} else {
swarn.path = path;
iterate_extent_inodes(fs_info, path, found_key.objectid,
- extent_offset,
+ extent_item_pos,
scrub_print_warning_inode, &swarn);
}