zram: register default groups with device_add_disk()

Register default sysfs groups during device_add_disk() to avoid a
race condition with udev during startup.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index a1d6b55..4879595 100644 (file)
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -1636,6 +1636,11 @@ static const struct attribute_group zram_disk_attr_group = {
        .attrs = zram_disk_attrs,
 };
 
+static const struct attribute_group *zram_disk_attr_groups[] = {
+       &zram_disk_attr_group,
+       NULL,
+};
+
 /*
  * Allocate and initialize new zram device. the function returns
  * '>= 0' device_id upon success, and negative value otherwise.
@@ -1716,24 +1721,14 @@ static int zram_add(void)
 
        zram->disk->queue->backing_dev_info->capabilities |=
                        (BDI_CAP_STABLE_WRITES | BDI_CAP_SYNCHRONOUS_IO);
-       add_disk(zram->disk);
-
-       ret = sysfs_create_group(&disk_to_dev(zram->disk)->kobj,
-                               &zram_disk_attr_group);
-       if (ret < 0) {
-               pr_err("Error creating sysfs group for device %d\n",
-                               device_id);
-               goto out_free_disk;
-       }
+       device_add_disk(NULL, zram->disk, zram_disk_attr_groups);
+
        strlcpy(zram->compressor, default_compressor, sizeof(zram->compressor));
 
        zram_debugfs_register(zram);
        pr_info("Added device: %s\n", zram->disk->disk_name);
        return device_id;
 
-out_free_disk:
-       del_gendisk(zram->disk);
-       put_disk(zram->disk);
 out_free_queue:
        blk_cleanup_queue(queue);
 out_free_idr:
@@ -1762,15 +1757,6 @@ static int zram_remove(struct zram *zram)
        mutex_unlock(&bdev->bd_mutex);
 
        zram_debugfs_unregister(zram);
-       /*
-        * Remove sysfs first, so no one will perform a disksize
-        * store while we destroy the devices. This also helps during
-        * hot_remove -- zram_reset_device() is the last holder of
-        * ->init_lock, no later/concurrent disksize_store() or any
-        * other sysfs handlers are possible.
-        */
-       sysfs_remove_group(&disk_to_dev(zram->disk)->kobj,
-                       &zram_disk_attr_group);
 
        /* Make sure all the pending I/O are finished */
        fsync_bdev(bdev);