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authorAnand Jain <anand.jain@oracle.com>2023-07-31 13:16:32 +0200
committerDavid Sterba <dsterba@suse.com>2023-08-21 14:54:48 +0200
commit4844c3664a72d36cc79752cb651c78860b14c240 (patch)
treeb5f589102b8fefa97abab40da23277689853e3b4 /fs/btrfs
parentbtrfs: remove v0 extent handling (diff)
downloadlinux-4844c3664a72d36cc79752cb651c78860b14c240.tar.xz
linux-4844c3664a72d36cc79752cb651c78860b14c240.zip
btrfs: add a helper to read the superblock metadata_uuid
In some cases, we need to read the FSID from the superblock when the metadata_uuid is not set, and otherwise, read the metadata_uuid. So, add a helper. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs')
-rw-r--r--fs/btrfs/volumes.c8
-rw-r--r--fs/btrfs/volumes.h1
2 files changed, 9 insertions, 0 deletions
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index bfdfecee1afe..2669206e6f15 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -681,6 +681,14 @@ error_free_page:
return -EINVAL;
}
+u8 *btrfs_sb_fsid_ptr(struct btrfs_super_block *sb)
+{
+ bool has_metadata_uuid = (btrfs_super_incompat_flags(sb) &
+ BTRFS_FEATURE_INCOMPAT_METADATA_UUID);
+
+ return has_metadata_uuid ? sb->metadata_uuid : sb->fsid;
+}
+
/*
* Handle scanned device having its CHANGING_FSID_V2 flag set and the fs_devices
* being created with a disk that has already completed its fsid change. Such
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index a59898d51e9e..2128a032c3b7 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -747,5 +747,6 @@ int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info);
bool btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical);
bool btrfs_pinned_by_swapfile(struct btrfs_fs_info *fs_info, void *ptr);
+u8 *btrfs_sb_fsid_ptr(struct btrfs_super_block *sb);
#endif