block: genhd: add 'groups' argument to device_add_disk

Update device_add_disk() to take an 'groups' argument so that
individual drivers can register a device with additional sysfs
attributes.
This avoids race condition the driver would otherwise have if these
groups were to be created with sysfs_add_groups().

Signed-off-by: Martin Wilck <martin.wilck@suse.com>
Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 14 insertions, 5 deletions

diff --git a/block/genhd.c b/block/genhd.c
index 8cc719a37b32..ef0936184d69 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -567,7 +567,8 @@ static int exact_lock(dev_t devt, void *data)
 	return 0;
 }
 
-static void register_disk(struct device *parent, struct gendisk *disk)
+static void register_disk(struct device *parent, struct gendisk *disk,
+			  const struct attribute_group **groups)
 {
 	struct device *ddev = disk_to_dev(disk);
 	struct block_device *bdev;
@@ -582,6 +583,10 @@ static void register_disk(struct device *parent, struct gendisk *disk)
 	/* delay uevents, until we scanned partition table */
 	dev_set_uevent_suppress(ddev, 1);
 
+	if (groups) {
+		WARN_ON(ddev->groups);
+		ddev->groups = groups;
+	}
 	if (device_add(ddev))
 		return;
 	if (!sysfs_deprecated) {
@@ -647,6 +652,7 @@ exit:
  * __device_add_disk - add disk information to kernel list
  * @parent: parent device for the disk
  * @disk: per-device partitioning information
+ * @groups: Additional per-device sysfs groups
  * @register_queue: register the queue if set to true
  *
  * This function registers the partitioning information in @disk
@@ -655,6 +661,7 @@ exit:
  * FIXME: error handling
  */
 static void __device_add_disk(struct device *parent, struct gendisk *disk,
+			      const struct attribute_group **groups,
 			      bool register_queue)
 {
 	dev_t devt;
@@ -698,7 +705,7 @@ static void __device_add_disk(struct device *parent, struct gendisk *disk,
 		blk_register_region(disk_devt(disk), disk->minors, NULL,
 				    exact_match, exact_lock, disk);
 	}
-	register_disk(parent, disk);
+	register_disk(parent, disk, groups);
 	if (register_queue)
 		blk_register_queue(disk);
 
@@ -712,15 +719,17 @@ static void __device_add_disk(struct device *parent, struct gendisk *disk,
 	blk_integrity_add(disk);
 }
 
-void device_add_disk(struct device *parent, struct gendisk *disk)
+void device_add_disk(struct device *parent, struct gendisk *disk,
+		     const struct attribute_group **groups)
+
 {
-	__device_add_disk(parent, disk, true);
+	__device_add_disk(parent, disk, groups, true);
 }
 EXPORT_SYMBOL(device_add_disk);
 
 void device_add_disk_no_queue_reg(struct device *parent, struct gendisk *disk)
 {
-	__device_add_disk(parent, disk, false);
+	__device_add_disk(parent, disk, NULL, false);
 }
 EXPORT_SYMBOL(device_add_disk_no_queue_reg);