Adds comments about BTRFS_FS_EXCL_OP to existing comments about the device locks.
Signed-off-by: Anand Jain <anand.j...@oracle.com> --- fs/btrfs/volumes.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 3a3912a9dec9..18306165ffaa 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -202,6 +202,22 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, * device_list_mutex * chunk_mutex * balance_mutex + * + * BTRFS_FS_EXCL_OP + * ---------------- + * Maintains the exclusivity of the following device operations. + * + * - Balance (*) + * - Add + * - Remove + * - Replace (*) + * - Resize + * + * The device operation with (*) indicate it can continue after a CLI pause + * (only balance can be paused using CLI) or remount or unmount-mount sequence + * or a power-recycle, as long as the FS is still writeable. And during the + * course of the pause, the BTRFS_FS_EXCL_OP remains set. BTRFS_FS_EXCL_OP flag + * is set and cleared using atomic functions. */ DEFINE_MUTEX(uuid_mutex); -- 2.15.0 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
