btrfs: introduce BTRFS_QGROUP_STATUS_FLAGS_MASK for later expansion

Currently we only have 3 qgroup flags:

- BTRFS_QGROUP_STATUS_FLAG_ON
- BTRFS_QGROUP_STATUS_FLAG_RESCAN
- BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT

These flags match the on-disk flags used in btrfs_qgroup_status.

But we're going to introduce extra runtime flags which will not reach
disks.

So here we introduce a new mask, BTRFS_QGROUP_STATUS_FLAGS_MASK, to
make sure only those flags can reach disks.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index ba323dcb0a0b8bbe7e60dc1b163d8027d036c35d..fc2ed19ced9b2779dc8e0a5b72afb34e1c8e8326 100644 (file)
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -878,7 +878,8 @@ static int update_qgroup_status_item(struct btrfs_trans_handle *trans)
        l = path->nodes[0];
        slot = path->slots[0];
        ptr = btrfs_item_ptr(l, slot, struct btrfs_qgroup_status_item);
-       btrfs_set_qgroup_status_flags(l, ptr, fs_info->qgroup_flags);
+       btrfs_set_qgroup_status_flags(l, ptr, fs_info->qgroup_flags &
+                                     BTRFS_QGROUP_STATUS_FLAGS_MASK);
        btrfs_set_qgroup_status_generation(l, ptr, trans->transid);
        btrfs_set_qgroup_status_rescan(l, ptr,
                                fs_info->qgroup_rescan_progress.objectid);
@@ -1052,7 +1053,8 @@ int btrfs_quota_enable(struct btrfs_fs_info *fs_info)
        btrfs_set_qgroup_status_version(leaf, ptr, BTRFS_QGROUP_STATUS_VERSION);
        fs_info->qgroup_flags = BTRFS_QGROUP_STATUS_FLAG_ON |
                                BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
-       btrfs_set_qgroup_status_flags(leaf, ptr, fs_info->qgroup_flags);
+       btrfs_set_qgroup_status_flags(leaf, ptr, fs_info->qgroup_flags &
+                                     BTRFS_QGROUP_STATUS_FLAGS_MASK);
        btrfs_set_qgroup_status_rescan(leaf, ptr, 0);
 
        btrfs_mark_buffer_dirty(leaf);

diff --git a/include/uapi/linux/btrfs_tree.h b/include/uapi/linux/btrfs_tree.h
index 5f32a2a495dc32aee9fc4669f0f2d85c34e26f30..1f7a38ec6ac316ca4d2f5fe03b1173aa736cea70 100644 (file)
--- a/include/uapi/linux/btrfs_tree.h
+++ b/include/uapi/linux/btrfs_tree.h
@@ -965,6 +965,10 @@ static inline __u16 btrfs_qgroup_level(__u64 qgroupid)
  */
 #define BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT  (1ULL << 2)
 
+#define BTRFS_QGROUP_STATUS_FLAGS_MASK (BTRFS_QGROUP_STATUS_FLAG_ON |          \
+                                        BTRFS_QGROUP_STATUS_FLAG_RESCAN |      \
+                                        BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT)
+
 #define BTRFS_QGROUP_STATUS_VERSION        1
 
 struct btrfs_qgroup_status_item {