btrfs: don't ignore inode missing when replaying log tree

During log replay, at add_inode_ref(), we return -ENOENT if our current
inode isn't found on the subvolume tree or if a parent directory isn't
found. The error comes from btrfs_iget_logging() <- btrfs_iget() <-
btrfs_read_locked_inode().

The single caller of add_inode_ref(), replay_one_buffer(), ignores an
-ENOENT error because it expects that error to mean only that a parent
directory wasn't found and that is ok.

Before commit 5f61b961599a ("btrfs: fix inode lookup error handling during
log replay") we were converting any error when getting a parent directory
to -ENOENT and any error when getting the current inode to -EIO, so our
caller would fail log replay in case we can't find the current inode.
After that commit however in case the current inode is not found we return
-ENOENT to the caller and therefore it ignores the critical fact that the
current inode was not found in the subvolume tree.

Fix this by converting -ENOENT to 0 when we don't find a parent directory,
returning -ENOENT when we don't find the current inode and making the
caller, replay_one_buffer(), not ignore -ENOENT anymore.

Fixes: 5f61b961599a ("btrfs: fix inode lookup error handling during log replay")
CC: stable@vger.kernel.org # 6.16
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index ab0815d9e7e5a22e192e8b3f5949b43548d31a5e..e3c77f3d092c2796583513d9b7e1ceee42deb93b 100644 (file)
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -1416,6 +1416,8 @@ static noinline int add_inode_ref(struct btrfs_trans_handle *trans,
        dir = btrfs_iget_logging(parent_objectid, root);
        if (IS_ERR(dir)) {
                ret = PTR_ERR(dir);
+               if (ret == -ENOENT)
+                       ret = 0;
                dir = NULL;
                goto out;
        }
@@ -1440,6 +1442,15 @@ static noinline int add_inode_ref(struct btrfs_trans_handle *trans,
                                if (IS_ERR(dir)) {
                                        ret = PTR_ERR(dir);
                                        dir = NULL;
+                                       /*
+                                        * A new parent dir may have not been
+                                        * logged and not exist in the subvolume
+                                        * tree, see the comment above before
+                                        * the loop when getting the first
+                                        * parent dir.
+                                        */
+                                       if (ret == -ENOENT)
+                                               ret = 0;
                                        goto out;
                                }
                        }
@@ -2551,9 +2562,8 @@ static int replay_one_buffer(struct btrfs_root *log, struct extent_buffer *eb,
                           key.type == BTRFS_INODE_EXTREF_KEY) {
                        ret = add_inode_ref(wc->trans, root, log, path,
                                            eb, i, &key);
-                       if (ret && ret != -ENOENT)
+                       if (ret)
                                break;
-                       ret = 0;
                } else if (key.type == BTRFS_EXTENT_DATA_KEY) {
                        ret = replay_one_extent(wc->trans, root, path,
                                                eb, i, &key);