Commit 7f9b348c authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

brd: convert to blk_alloc_disk/blk_cleanup_disk 



Convert the brd driver to use the blk_alloc_disk and blk_cleanup_disk
helpers to simplify gendisk and request_queue allocation.  This also
allows to remove the request_queue pointer in struct request_queue,
and to simplify the initialization as blk_cleanup_disk can be called
on any disk returned from blk_alloc_disk.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
Reviewed-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210521055116.1053587-7-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent f525464a

drivers/block/brd.c

+33 −61
Original line number Diff line number Diff line
@@ -39,8 +39,6 @@ 
 */

struct brd_device {

	int			brd_number;



	struct request_queue	*brd_queue;

	struct gendisk		*brd_disk;

	struct list_head	brd_list;
@@ -372,7 +370,7 @@ static LIST_HEAD(brd_devices); 
static DEFINE_MUTEX(brd_devices_mutex);

static struct dentry *brd_debugfs_dir;



static struct brd_device *brd_alloc(int i)

static int brd_alloc(int i)

{

	struct brd_device *brd;

	struct gendisk *disk;
@@ -380,64 +378,55 @@ static struct brd_device *brd_alloc(int i) 


	brd = kzalloc(sizeof(*brd), GFP_KERNEL);

	if (!brd)

		goto out;

		return -ENOMEM;

	brd->brd_number		= i;

	spin_lock_init(&brd->brd_lock);

	INIT_RADIX_TREE(&brd->brd_pages, GFP_ATOMIC);



	brd->brd_queue = blk_alloc_queue(NUMA_NO_NODE);

	if (!brd->brd_queue)

		goto out_free_dev;



	snprintf(buf, DISK_NAME_LEN, "ram%d", i);

	if (!IS_ERR_OR_NULL(brd_debugfs_dir))

		debugfs_create_u64(buf, 0444, brd_debugfs_dir,

				&brd->brd_nr_pages);



	/* This is so fdisk will align partitions on 4k, because of

	 * direct_access API needing 4k alignment, returning a PFN

	 * (This is only a problem on very small devices <= 4M,

	 *  otherwise fdisk will align on 1M. Regardless this call

	 *  is harmless)

	 */

	blk_queue_physical_block_size(brd->brd_queue, PAGE_SIZE);

	disk = brd->brd_disk = alloc_disk(max_part);

	disk = brd->brd_disk = blk_alloc_disk(NUMA_NO_NODE);

	if (!disk)

		goto out_free_queue;

		goto out_free_dev;



	disk->major		= RAMDISK_MAJOR;

	disk->first_minor	= i * max_part;

	disk->minors		= max_part;

	disk->fops		= &brd_fops;

	disk->private_data	= brd;

	disk->flags		= GENHD_FL_EXT_DEVT;

	strlcpy(disk->disk_name, buf, DISK_NAME_LEN);

	set_capacity(disk, rd_size * 2);

	

	/*

	 * This is so fdisk will align partitions on 4k, because of

	 * direct_access API needing 4k alignment, returning a PFN

	 * (This is only a problem on very small devices <= 4M,

	 *  otherwise fdisk will align on 1M. Regardless this call

	 *  is harmless)

	 */

	blk_queue_physical_block_size(disk->queue, PAGE_SIZE);



	/* Tell the block layer that this is not a rotational device */

	blk_queue_flag_set(QUEUE_FLAG_NONROT, brd->brd_queue);

	blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, brd->brd_queue);

	blk_queue_flag_set(QUEUE_FLAG_NONROT, disk->queue);

	blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, disk->queue);

	add_disk(disk);

	list_add_tail(&brd->brd_list, &brd_devices);



	return brd;

	return 0;



out_free_queue:

	blk_cleanup_queue(brd->brd_queue);

out_free_dev:

	kfree(brd);

out:

	return NULL;

}



static void brd_free(struct brd_device *brd)

{

	put_disk(brd->brd_disk);

	blk_cleanup_queue(brd->brd_queue);

	brd_free_pages(brd);

	kfree(brd);

	return -ENOMEM;

}



static void brd_probe(dev_t dev)

{

	struct brd_device *brd;

	int i = MINOR(dev) / max_part;

	struct brd_device *brd;



	mutex_lock(&brd_devices_mutex);

	list_for_each_entry(brd, &brd_devices, brd_list) {
@@ -445,13 +434,7 @@ static void brd_probe(dev_t dev) 
			goto out_unlock;

	}



	brd = brd_alloc(i);

	if (brd) {

		brd->brd_disk->queue = brd->brd_queue;

		add_disk(brd->brd_disk);

		list_add_tail(&brd->brd_list, &brd_devices);

	}



	brd_alloc(i);

out_unlock:

	mutex_unlock(&brd_devices_mutex);

}
@@ -460,7 +443,9 @@ static void brd_del_one(struct brd_device *brd) 
{

	list_del(&brd->brd_list);

	del_gendisk(brd->brd_disk);

	brd_free(brd);

	blk_cleanup_disk(brd->brd_disk);

	brd_free_pages(brd);

	kfree(brd);

}



static inline void brd_check_and_reset_par(void)
@@ -485,7 +470,7 @@ static inline void brd_check_and_reset_par(void) 
static int __init brd_init(void)

{

	struct brd_device *brd, *next;

	int i;

	int err, i;



	/*

	 * brd module now has a feature to instantiate underlying device
@@ -511,22 +496,11 @@ static int __init brd_init(void) 


	mutex_lock(&brd_devices_mutex);

	for (i = 0; i < rd_nr; i++) {

		brd = brd_alloc(i);

		if (!brd)

		err = brd_alloc(i);

		if (err)

			goto out_free;

		list_add_tail(&brd->brd_list, &brd_devices);

	}



	/* point of no return */



	list_for_each_entry(brd, &brd_devices, brd_list) {

		/*

		 * associate with queue just before adding disk for

		 * avoiding to mess up failure path

		 */

		brd->brd_disk->queue = brd->brd_queue;

		add_disk(brd->brd_disk);

	}

	mutex_unlock(&brd_devices_mutex);



	pr_info("brd: module loaded\n");
@@ -535,15 +509,13 @@ static int __init brd_init(void) 
out_free:

	debugfs_remove_recursive(brd_debugfs_dir);



	list_for_each_entry_safe(brd, next, &brd_devices, brd_list) {

		list_del(&brd->brd_list);

		brd_free(brd);

	}

	list_for_each_entry_safe(brd, next, &brd_devices, brd_list)

		brd_del_one(brd);

	mutex_unlock(&brd_devices_mutex);

	unregister_blkdev(RAMDISK_MAJOR, "ramdisk");



	pr_info("brd: module NOT loaded !!!\n");

	return -ENOMEM;

	return err;

}



static void __exit brd_exit(void)