btrfs: sipmlify uuid parameters of alloc_fs_devices()

Among all the callers, only the device_list_add() function uses the
second argument of alloc_fs_devices(). It passes metadata_uuid when
available, otherwise, it passes NULL. And in turn, alloc_fs_devices()
is designed to copy either metadata_uuid or fsid into
fs_devices::metadata_uuid.

So remove the second argument in alloc_fs_devices(), and always copy the
fsid.  In the caller device_list_add() function, we will overwrite it
with metadata_uuid when it is available.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Anand Jain 2023-08-23 22:52:13 +08:00 committed by David Sterba
parent 01fc062bd0
commit f7361d8c3f
2 changed files with 18 additions and 17 deletions

View File

@ -318,9 +318,10 @@ static bool check_tree_block_fsid(struct extent_buffer *eb)
BTRFS_FSID_SIZE);
/*
* alloc_fs_devices() copies the fsid into metadata_uuid if the
* metadata_uuid is unset in the superblock, including for a seed device.
* So, we can use fs_devices->metadata_uuid.
* alloc_fsid_devices() copies the fsid into fs_devices::metadata_uuid.
* This is then overwritten by metadata_uuid if it is present in the
* device_list_add(). The same true for a seed device as well. So use of
* fs_devices::metadata_uuid is appropriate here.
*/
if (memcmp(fsid, fs_info->fs_devices->metadata_uuid, BTRFS_FSID_SIZE) == 0)
return false;

View File

@ -357,21 +357,19 @@ struct list_head * __attribute_const__ btrfs_get_fs_uuids(void)
}
/*
* alloc_fs_devices - allocate struct btrfs_fs_devices
* @fsid: if not NULL, copy the UUID to fs_devices::fsid
* @metadata_fsid: if not NULL, copy the UUID to fs_devices::metadata_fsid
* Allocate new btrfs_fs_devices structure identified by a fsid.
*
* @fsid: if not NULL, copy the UUID to fs_devices::fsid and to
* fs_devices::metadata_fsid
*
* Return a pointer to a new struct btrfs_fs_devices on success, or ERR_PTR().
* The returned struct is not linked onto any lists and can be destroyed with
* kfree() right away.
*/
static struct btrfs_fs_devices *alloc_fs_devices(const u8 *fsid,
const u8 *metadata_fsid)
static struct btrfs_fs_devices *alloc_fs_devices(const u8 *fsid)
{
struct btrfs_fs_devices *fs_devs;
ASSERT(fsid || !metadata_fsid);
fs_devs = kzalloc(sizeof(*fs_devs), GFP_KERNEL);
if (!fs_devs)
return ERR_PTR(-ENOMEM);
@ -385,8 +383,7 @@ static struct btrfs_fs_devices *alloc_fs_devices(const u8 *fsid,
if (fsid) {
memcpy(fs_devs->fsid, fsid, BTRFS_FSID_SIZE);
memcpy(fs_devs->metadata_uuid,
metadata_fsid ?: fsid, BTRFS_FSID_SIZE);
memcpy(fs_devs->metadata_uuid, fsid, BTRFS_FSID_SIZE);
}
return fs_devs;
@ -812,8 +809,11 @@ static noinline struct btrfs_device *device_list_add(const char *path,
if (!fs_devices) {
fs_devices = alloc_fs_devices(disk_super->fsid,
has_metadata_uuid ? disk_super->metadata_uuid : NULL);
fs_devices = alloc_fs_devices(disk_super->fsid);
if (has_metadata_uuid)
memcpy(fs_devices->metadata_uuid,
disk_super->metadata_uuid, BTRFS_FSID_SIZE);
if (IS_ERR(fs_devices))
return ERR_CAST(fs_devices);
@ -997,7 +997,7 @@ static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
lockdep_assert_held(&uuid_mutex);
fs_devices = alloc_fs_devices(orig->fsid, NULL);
fs_devices = alloc_fs_devices(orig->fsid);
if (IS_ERR(fs_devices))
return fs_devices;
@ -2451,7 +2451,7 @@ static struct btrfs_fs_devices *btrfs_init_sprout(struct btrfs_fs_info *fs_info)
* Private copy of the seed devices, anchored at
* fs_info->fs_devices->seed_list
*/
seed_devices = alloc_fs_devices(NULL, NULL);
seed_devices = alloc_fs_devices(NULL);
if (IS_ERR(seed_devices))
return seed_devices;
@ -6901,7 +6901,7 @@ static struct btrfs_fs_devices *open_seed_devices(struct btrfs_fs_info *fs_info,
if (!btrfs_test_opt(fs_info, DEGRADED))
return ERR_PTR(-ENOENT);
fs_devices = alloc_fs_devices(fsid, NULL);
fs_devices = alloc_fs_devices(fsid);
if (IS_ERR(fs_devices))
return fs_devices;