[PATCH 1/8] btrfs-progs: Add btrfs_is_empty_uuid
From: Nikolay Borisov <hidden>
Date: 2021-09-13 13:18:39
Subsystem:
the rest · Maintainer:
Linus Torvalds
This utility function is needed by the RO->RW snapshot detection code. Signed-off-by: Nikolay Borisov <redacted> --- kernel-shared/ctree.h | 2 ++ kernel-shared/uuid-tree.c | 11 +++++++++++ 2 files changed, 13 insertions(+)
diff --git a/kernel-shared/ctree.h b/kernel-shared/ctree.h
index 3cca60323e3d..f53436a7f38b 100644
--- a/kernel-shared/ctree.h
+++ b/kernel-shared/ctree.h@@ -2860,6 +2860,8 @@ int btrfs_lookup_uuid_received_subvol_item(int fd, const u8 *uuid, int btrfs_uuid_tree_add(struct btrfs_trans_handle *trans, u8 *uuid, u8 type, u64 subvol_id_cpu); +int btrfs_is_empty_uuid(u8 *uuid); + static inline int is_fstree(u64 rootid) { if (rootid == BTRFS_FS_TREE_OBJECTID ||
diff --git a/kernel-shared/uuid-tree.c b/kernel-shared/uuid-tree.c
index 21115a4d2d09..51a7b5d9ff5d 100644
--- a/kernel-shared/uuid-tree.c
+++ b/kernel-shared/uuid-tree.c@@ -109,3 +109,14 @@ int btrfs_lookup_uuid_received_subvol_item(int fd, const u8 *uuid, BTRFS_UUID_KEY_RECEIVED_SUBVOL, subvol_id); } + +int btrfs_is_empty_uuid(u8 *uuid) +{ + int i; + + for (i = 0; i < BTRFS_UUID_SIZE; i++) { + if (uuid[i]) + return 0; + } + return 1; +}
--
2.17.1