Commit cbbc34ab authored Jul 04, 2019 by Filipe Manana Committed by Greg Kroah-Hartman Jan 27, 2020

Btrfs: fix inode cache waiters hanging on path allocation failure



[ Upstream commit 9d123a35d7e97bb2139747b16127c9b22b6a593e ]

If the caching thread fails to allocate a path, it returns without waking
up any cache waiters, leaving them hang forever. Fix this by following the
same approach as when we fail to start the caching thread: print an error
message, disable inode caching and make the wakers fallback to non-caching
mode behaviour (calling btrfs_find_free_objectid()).

Fixes: 581bb050 ("Btrfs: Cache free inode numbers in memory")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent b34203a5

fs/btrfs/inode-map.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -41,8 +41,10 @@ static int caching_kthread(void *data)
		return 0;

		path = btrfs_alloc_path();
		if (!path)
		if (!path) {
		fail_caching_thread(root);
		return -ENOMEM;
		}

		/* Since the commit root is read-only, we can safely skip locking. */
		path->skip_locking = 1;