path: root/fs/btrfs/volumes.h
diff options
authorNikolay Borisov <nborisov@suse.com>2018-10-30 16:43:26 +0200
committerDavid Sterba <dsterba@suse.com>2018-12-17 14:51:38 +0100
commitd1a63002829a4d8014de20dc141b404cc808405e (patch)
tree0734637651debfcf49ac8c20c8711a4924d131bd /fs/btrfs/volumes.h
parentbtrfs: Add handling for disk split-brain scenario during fsid change (diff)
btrfs: add members to fs_devices to track fsid changes
In order to gracefully handle split-brain scenario during fsid change (which are very unlikely, yet possible), two more pieces of information will be necessary: 1. The highest generation number among all devices registered to a particular btrfs_fs_devices 2. A boolean flag whether a given btrfs_fs_devices was created by a device which had the FSID_CHANGING_V2 flag set. This is a preparatory patch and just introduces the variables as well as code which sets them, their actual use is going to happen in a later patch. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/volumes.h')
1 files changed, 5 insertions, 0 deletions
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index bdee4b60e0ba..1d936ce282c3 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -211,6 +211,7 @@ BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
struct btrfs_fs_devices {
u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
u8 metadata_uuid[BTRFS_FSID_SIZE];
+ bool fsid_change;
struct list_head fs_list;
u64 num_devices;
@@ -219,6 +220,10 @@ struct btrfs_fs_devices {
u64 missing_devices;
u64 total_rw_bytes;
u64 total_devices;
+ /* Highest generation number of seen devices */
+ u64 latest_generation;
struct block_device *latest_bdev;
/* all of the devices in the FS, protected by a mutex