btrfs: dev delete should remove sysfs entry

when we delete the device from the mounted btrfs,
we would need its corresponding sysfs enty to
be removed as well.
Signed-off-by: Anand Jain <Anand.Jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>

fs/btrfs/sysfs.c

@@ -605,6 +605,26 @@ static void init_feature_attrs(void)
 	}
 }
 
+int btrfs_kobj_rm_device(struct btrfs_fs_info *fs_info,
+		struct btrfs_device *one_device)
+{
+	struct hd_struct *disk;
+	struct kobject *disk_kobj;
+
+	if (!fs_info->device_dir_kobj)
+		return -EINVAL;
+
+	if (one_device) {
+		disk = one_device->bdev->bd_part;
+		disk_kobj = &part_to_dev(disk)->kobj;
+
+		sysfs_remove_link(fs_info->device_dir_kobj,
+						disk_kobj->name);
+	}
+
+	return 0;
+}
+
 static int btrfs_kobj_add_device(struct btrfs_fs_info *fs_info)
 {
 	int error = 0;

fs/btrfs/sysfs.h

@@ -66,4 +66,6 @@ char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags);
 extern const char * const btrfs_feature_set_names[3];
 extern struct kobj_type space_info_ktype;
 extern struct kobj_type btrfs_raid_ktype;
+int btrfs_kobj_rm_device(struct btrfs_fs_info *fs_info,
+                struct btrfs_device *one_device);
 #endif /* _BTRFS_SYSFS_H_ */

fs/btrfs/volumes.c

@@ -40,6 +40,7 @@
 #include "rcu-string.h"
 #include "math.h"
 #include "dev-replace.h"
+#include "sysfs.h"
 
 static int init_first_rw_device(struct btrfs_trans_handle *trans,
 				struct btrfs_root *root,
@@ -1680,6 +1681,9 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path)
 	if (device->bdev)
 		device->fs_devices->open_devices--;
 
+	/* remove sysfs entry */
+	btrfs_kobj_rm_device(root->fs_info, device);
+
 	call_rcu(&device->rcu, free_device);
 
 	num_devices = btrfs_super_num_devices(root->fs_info->super_copy) - 1;