Btrfs: add DEVICE_READY ioctl
This will be used in conjunction with btrfs device ready <dev>. This is
needed for initrd's to have a nice and lightweight way to tell if all of the
devices needed for a file system are in the cache currently. This keeps
them from having to do mount+sleep loops waiting for devices to show up.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 88a2d2b..26da344 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -1462,6 +1462,13 @@
ret = btrfs_scan_one_device(vol->name, FMODE_READ,
&btrfs_fs_type, &fs_devices);
break;
+ case BTRFS_IOC_DEVICES_READY:
+ ret = btrfs_scan_one_device(vol->name, FMODE_READ,
+ &btrfs_fs_type, &fs_devices);
+ if (ret)
+ break;
+ ret = !(fs_devices->num_devices == fs_devices->total_devices);
+ break;
}
kfree(vol);