Extern or forward variable declaration at fs/btrfs/volumes.h, line 20 References: fs/btrfs/check-integrity.c, line 328 fs/btrfs/check-integrity.c, line 335 fs/btrfs/check-integrity.c, line 772 fs/btrfs/check-integrity.c, line 1748 fs/btrfs/check-integrity.c, line 2151 fs/btrfs/check-integrity.c, line 2735 fs/btrfs/disk-io.c, line 2603 fs/btrfs/disk-io.c, line 3387 fs/btrfs/disk-io.c, line 3409 fs/btrfs/disk-io.c, line 3411 fs/btrfs/disk-io.c, line 3439 fs/btrfs/disk-io.c, line 3441 fs/btrfs/disk-io.c, line 3442 fs/btrfs/disk-io.c, line 3490 fs/btrfs/disk-io.c, line 3559 fs/btrfs/inode.c, line 7623 fs/btrfs/inode.c, line 7643 fs/btrfs/inode.c, line 7741 fs/btrfs/volumes.c, line 470 fs/btrfs/volumes.c, line 787 fs/btrfs/volumes.c, line 2351 fs/btrfs/volumes.c, line 7562 fs/btrfs/volumes.h, line 20