btrfs: set inode flag BTRFS_INODE_COPY_EVERYTHING when logging new name

If we are logging a new name make sure our inode has the runtime flag
BTRFS_INODE_COPY_EVERYTHING set so that at btrfs_log_inode() we will find
new inode refs/extrefs in the subvolume tree and copy them into the log
tree.

We are currently doing it when adding a new link but we are missing it
when renaming.

An example where this makes a new name not persisted:

  1) create symlink with name foo in directory A
  2) fsync directory A, which persists the symlink
  3) rename the symlink from foo to bar
  4) fsync directory A to persist the new symlink name

Step 4 isn't working correctly as it's not logging the new name and also
leaving the old inode ref in the log tree, so after a power failure the
symlink still has the old name of "foo". This is because when we first
fsync directoy A we log the symlink's inode (as it's a new entry) and at
btrfs_log_inode() we set the log mode to LOG_INODE_ALL and then because
we are using that mode and the inode has the runtime flag
BTRFS_INODE_NEEDS_FULL_SYNC set, we clear that flag as well as the flag
BTRFS_INODE_COPY_EVERYTHING. That means the next time we log the inode,
during the rename through the call to btrfs_log_new_name() (calling
btrfs_log_inode_parent() and then btrfs_log_inode()), we will not search
the subvolume tree for new refs/extrefs and jump directory to the
'log_extents' label.

Fix this by making sure we set BTRFS_INODE_COPY_EVERYTHING on an inode
when we are about to log a new name. A test case for fstests will follow
soon.

Reported-by: Vyacheslav Kovalevsky <slava.kovalevskiy.2014@gmail.com>
Link: https://lore.kernel.org/linux-btrfs/ac949c74-90c2-4b9a-b7fd-1ffc5c3175c7@gmail.com/
Reviewed-by: Boris Burkov <boris@bur.io>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 6aad6b65522b..00a59fb79167 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -7910,6 +7910,9 @@ void btrfs_log_new_name(struct btrfs_trans_handle *trans,
 	bool log_pinned = false;
 	int ret;
 
+	/* The inode has a new name (ref/extref), so make sure we log it. */
+	set_bit(BTRFS_INODE_COPY_EVERYTHING, &inode->runtime_flags);
+
 	btrfs_init_log_ctx(&ctx, inode);
 	ctx.logging_new_name = true;