btrfs: switch seed device to list api
While this patch touches a bunch of files the conversion is
straighforward. Instead of using the implicit linked list anchored at
btrfs_fs_devices::seed the code is switched to using
list_for_each_entry.
Previous patches in the series already factored out code that processed
both main and seed devices so in those cases the factored out functions
are called on the main fs_devices and then on every seed dev inside
list_for_each_entry.
Using list api also allows to simplify deletion from the seed dev list
performed in btrfs_rm_device and btrfs_rm_dev_replace_free_srcdev by
substituting a while() loop with a simple list_del_init.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index a496219..84799ef 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -545,33 +545,30 @@ static int csum_dirty_buffer(struct btrfs_fs_info *fs_info, struct page *page)
static int check_tree_block_fsid(struct extent_buffer *eb)
{
struct btrfs_fs_info *fs_info = eb->fs_info;
- struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
+ struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;
u8 fsid[BTRFS_FSID_SIZE];
- int ret = 1;
+ u8 *metadata_uuid;
read_extent_buffer(eb, fsid, offsetof(struct btrfs_header, fsid),
BTRFS_FSID_SIZE);
- while (fs_devices) {
- u8 *metadata_uuid;
+ /*
+ * Checking the incompat flag is only valid for the current fs. For
+ * seed devices it's forbidden to have their uuid changed so reading
+ * ->fsid in this case is fine
+ */
+ if (btrfs_fs_incompat(fs_info, METADATA_UUID))
+ metadata_uuid = fs_devices->metadata_uuid;
+ else
+ metadata_uuid = fs_devices->fsid;
- /*
- * Checking the incompat flag is only valid for the current
- * fs. For seed devices it's forbidden to have their uuid
- * changed so reading ->fsid in this case is fine
- */
- if (fs_devices == fs_info->fs_devices &&
- btrfs_fs_incompat(fs_info, METADATA_UUID))
- metadata_uuid = fs_devices->metadata_uuid;
- else
- metadata_uuid = fs_devices->fsid;
+ if (!memcmp(fsid, metadata_uuid, BTRFS_FSID_SIZE))
+ return 0;
- if (!memcmp(fsid, metadata_uuid, BTRFS_FSID_SIZE)) {
- ret = 0;
- break;
- }
- fs_devices = fs_devices->seed;
- }
- return ret;
+ list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list)
+ if (!memcmp(fsid, seed_devs->fsid, BTRFS_FSID_SIZE))
+ return 0;
+
+ return 1;
}
static int btree_readpage_end_io_hook(struct btrfs_io_bio *io_bio,