btrfs: add btrfs_sysfs_add_device helper

btrfs_sysfs_add_devices_dir() adds device link and devid kobject
(sysfs entries) for a device or all the devices in the btrfs_fs_devices.
In preparation to add these sysfs entries for the seed as well, add
a btrfs_sysfs_add_device() helper function and avoid code duplication.

Reviewed-by: Josef Bacik <josef@toxicpanda.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>

diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index eb8f235..8ffe5df 100644 (file)
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -1312,44 +1312,70 @@ static struct kobj_type devid_ktype = {
        .release        = btrfs_release_devid_kobj,
 };
 
-int btrfs_sysfs_add_devices_dir(struct btrfs_fs_devices *fs_devices,
-                               struct btrfs_device *one_device)
+static int btrfs_sysfs_add_device(struct btrfs_device *device)
 {
-       int error = 0;
-       struct btrfs_device *dev;
+       int ret;
        unsigned int nofs_flag;
+       struct kobject *devices_kobj;
+       struct kobject *devinfo_kobj;
+
+       /*
+        * Make sure we use the fs_info::fs_devices to fetch the kobjects even
+        * for the seed fs_devices
+        */
+       devices_kobj = device->fs_info->fs_devices->devices_kobj;
+       devinfo_kobj = device->fs_info->fs_devices->devinfo_kobj;
+       ASSERT(devices_kobj);
+       ASSERT(devinfo_kobj);
 
        nofs_flag = memalloc_nofs_save();
-       list_for_each_entry(dev, &fs_devices->devices, dev_list) {
 
-               if (one_device && one_device != dev)
-                       continue;
+       if (device->bdev) {
+               struct hd_struct *disk;
+               struct kobject *disk_kobj;
 
-               if (dev->bdev) {
-                       struct hd_struct *disk;
-                       struct kobject *disk_kobj;
+               disk = device->bdev->bd_part;
+               disk_kobj = &part_to_dev(disk)->kobj;
 
-                       disk = dev->bdev->bd_part;
-                       disk_kobj = &part_to_dev(disk)->kobj;
-
-                       error = sysfs_create_link(fs_devices->devices_kobj,
-                                                 disk_kobj, disk_kobj->name);
-                       if (error)
-                               break;
+               ret = sysfs_create_link(devices_kobj, disk_kobj, disk_kobj->name);
+               if (ret) {
+                       btrfs_warn(device->fs_info,
+                               "creating sysfs device link for devid %llu failed: %d",
+                               device->devid, ret);
+                       goto out;
                }
+       }
 
-               init_completion(&dev->kobj_unregister);
-               error = kobject_init_and_add(&dev->devid_kobj, &devid_ktype,
-                                            fs_devices->devinfo_kobj, "%llu",
-                                            dev->devid);
-               if (error) {
-                       kobject_put(&dev->devid_kobj);
-                       break;
-               }
+       init_completion(&device->kobj_unregister);
+       ret = kobject_init_and_add(&device->devid_kobj, &devid_ktype,
+                                  devinfo_kobj, "%llu", device->devid);
+       if (ret) {
+               kobject_put(&device->devid_kobj);
+               btrfs_warn(device->fs_info,
+                          "devinfo init for devid %llu failed: %d",
+                          device->devid, ret);
        }
+
+out:
        memalloc_nofs_restore(nofs_flag);
+       return ret;
+}
 
-       return error;
+int btrfs_sysfs_add_devices_dir(struct btrfs_fs_devices *fs_devices,
+                               struct btrfs_device *device)
+{
+       int ret;
+
+       if (device)
+               return btrfs_sysfs_add_device(device);
+
+       list_for_each_entry(device, &fs_devices->devices, dev_list) {
+               ret = btrfs_sysfs_add_device(device);
+               if (ret)
+                       return ret;
+       }
+
+       return 0;
 }
 
 void btrfs_kobject_uevent(struct block_device *bdev, enum kobject_action action)