[linux.git] / block / blk-zoned.c

/*
 * Zoned block device handling
 *
 * Copyright (c) 2015, Hannes Reinecke
 * Copyright (c) 2015, SUSE Linux GmbH
 *
 * Copyright (c) 2016, Damien Le Moal
 * Copyright (c) 2016, Western Digital
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/rbtree.h>
#include <linux/blkdev.h>

static inline sector_t blk_zone_start(struct request_queue *q,
				      sector_t sector)
{
	sector_t zone_mask = blk_queue_zone_sectors(q) - 1;

	return sector & ~zone_mask;
}

/*
 * Return true if a request is a write requests that needs zone write locking.
 */
bool blk_req_needs_zone_write_lock(struct request *rq)
{
	if (!rq->q->seq_zones_wlock)
		return false;

	if (blk_rq_is_passthrough(rq))
		return false;

	switch (req_op(rq)) {
	case REQ_OP_WRITE_ZEROES:
	case REQ_OP_WRITE_SAME:
	case REQ_OP_WRITE:
		return blk_rq_zone_is_seq(rq);
	default:
		return false;
	}
}
EXPORT_SYMBOL_GPL(blk_req_needs_zone_write_lock);

void __blk_req_zone_write_lock(struct request *rq)
{
	if (WARN_ON_ONCE(test_and_set_bit(blk_rq_zone_no(rq),
					  rq->q->seq_zones_wlock)))
		return;

	WARN_ON_ONCE(rq->rq_flags & RQF_ZONE_WRITE_LOCKED);
	rq->rq_flags |= RQF_ZONE_WRITE_LOCKED;
}
EXPORT_SYMBOL_GPL(__blk_req_zone_write_lock);

void __blk_req_zone_write_unlock(struct request *rq)
{
	rq->rq_flags &= ~RQF_ZONE_WRITE_LOCKED;
	if (rq->q->seq_zones_wlock)
		WARN_ON_ONCE(!test_and_clear_bit(blk_rq_zone_no(rq),
						 rq->q->seq_zones_wlock));
}
EXPORT_SYMBOL_GPL(__blk_req_zone_write_unlock);

/*
 * Check that a zone report belongs to the partition.
 * If yes, fix its start sector and write pointer, copy it in the
 * zone information array and return true. Return false otherwise.
 */
static bool blkdev_report_zone(struct block_device *bdev,
			       struct blk_zone *rep,
			       struct blk_zone *zone)
{
	sector_t offset = get_start_sect(bdev);

	if (rep->start < offset)
		return false;

	rep->start -= offset;
	if (rep->start + rep->len > bdev->bd_part->nr_sects)
		return false;

	if (rep->type == BLK_ZONE_TYPE_CONVENTIONAL)
		rep->wp = rep->start + rep->len;
	else
		rep->wp -= offset;
	memcpy(zone, rep, sizeof(struct blk_zone));

	return true;
}

/**
 * blkdev_report_zones - Get zones information
 * @bdev:	Target block device
 * @sector:	Sector from which to report zones
 * @zones:	Array of zone structures where to return the zones information
 * @nr_zones:	Number of zone structures in the zone array
 * @gfp_mask:	Memory allocation flags (for bio_alloc)
 *
 * Description:
 *    Get zone information starting from the zone containing @sector.
 *    The number of zone information reported may be less than the number
 *    requested by @nr_zones. The number of zones actually reported is
 *    returned in @nr_zones.
 */
int blkdev_report_zones(struct block_device *bdev,
			sector_t sector,
			struct blk_zone *zones,
			unsigned int *nr_zones,
			gfp_t gfp_mask)
{
	struct request_queue *q = bdev_get_queue(bdev);
	struct blk_zone_report_hdr *hdr;
	unsigned int nrz = *nr_zones;
	struct page *page;
	unsigned int nr_rep;
	size_t rep_bytes;
	unsigned int nr_pages;
	struct bio *bio;
	struct bio_vec *bv;
	unsigned int i, n, nz;
	unsigned int ofst;
	void *addr;
	int ret;

	if (!q)
		return -ENXIO;

	if (!blk_queue_is_zoned(q))
		return -EOPNOTSUPP;

	if (!nrz)
		return 0;

	if (sector > bdev->bd_part->nr_sects) {
		*nr_zones = 0;
		return 0;
	}

	/*
	 * The zone report has a header. So make room for it in the
	 * payload. Also make sure that the report fits in a single BIO
	 * that will not be split down the stack.
	 */
	rep_bytes = sizeof(struct blk_zone_report_hdr) +
		sizeof(struct blk_zone) * nrz;
	rep_bytes = (rep_bytes + PAGE_SIZE - 1) & PAGE_MASK;
	if (rep_bytes > (queue_max_sectors(q) << 9))
		rep_bytes = queue_max_sectors(q) << 9;

	nr_pages = min_t(unsigned int, BIO_MAX_PAGES,
			 rep_bytes >> PAGE_SHIFT);
	nr_pages = min_t(unsigned int, nr_pages,
			 queue_max_segments(q));

	bio = bio_alloc(gfp_mask, nr_pages);
	if (!bio)
		return -ENOMEM;

	bio_set_dev(bio, bdev);
	bio->bi_iter.bi_sector = blk_zone_start(q, sector);
	bio_set_op_attrs(bio, REQ_OP_ZONE_REPORT, 0);

	for (i = 0; i < nr_pages; i++) {
		page = alloc_page(gfp_mask);
		if (!page) {
			ret = -ENOMEM;
			goto out;
		}
		if (!bio_add_page(bio, page, PAGE_SIZE, 0)) {
			__free_page(page);
			break;
		}
	}

	if (i == 0)
		ret = -ENOMEM;
	else
		ret = submit_bio_wait(bio);
	if (ret)
		goto out;

	/*
	 * Process the report result: skip the header and go through the
	 * reported zones to fixup and fixup the zone information for
	 * partitions. At the same time, return the zone information into
	 * the zone array.
	 */
	n = 0;
	nz = 0;
	nr_rep = 0;
	bio_for_each_segment_all(bv, bio, i) {

		if (!bv->bv_page)
			break;

		addr = kmap_atomic(bv->bv_page);

		/* Get header in the first page */
		ofst = 0;
		if (!nr_rep) {
			hdr = (struct blk_zone_report_hdr *) addr;
			nr_rep = hdr->nr_zones;
			ofst = sizeof(struct blk_zone_report_hdr);
		}

		/* Fixup and report zones */
		while (ofst < bv->bv_len &&
		       n < nr_rep && nz < nrz) {
			if (blkdev_report_zone(bdev, addr + ofst, &zones[nz]))
				nz++;
			ofst += sizeof(struct blk_zone);
			n++;
		}

		kunmap_atomic(addr);

		if (n >= nr_rep || nz >= nrz)
			break;

	}

	*nr_zones = nz;
out:
	bio_for_each_segment_all(bv, bio, i)
		__free_page(bv->bv_page);
	bio_put(bio);

	return ret;
}
EXPORT_SYMBOL_GPL(blkdev_report_zones);

/**
 * blkdev_reset_zones - Reset zones write pointer
 * @bdev:	Target block device
 * @sector:	Start sector of the first zone to reset
 * @nr_sectors:	Number of sectors, at least the length of one zone
 * @gfp_mask:	Memory allocation flags (for bio_alloc)
 *
 * Description:
 *    Reset the write pointer of the zones contained in the range
 *    @sector..@sector+@nr_sectors. Specifying the entire disk sector range
 *    is valid, but the specified range should not contain conventional zones.
 */
int blkdev_reset_zones(struct block_device *bdev,
		       sector_t sector, sector_t nr_sectors,
		       gfp_t gfp_mask)
{
	struct request_queue *q = bdev_get_queue(bdev);
	sector_t zone_sectors;
	sector_t end_sector = sector + nr_sectors;
	struct bio *bio;
	int ret;

	if (!q)
		return -ENXIO;

	if (!blk_queue_is_zoned(q))
		return -EOPNOTSUPP;

	if (end_sector > bdev->bd_part->nr_sects)
		/* Out of range */
		return -EINVAL;

	/* Check alignment (handle eventual smaller last zone) */
	zone_sectors = blk_queue_zone_sectors(q);
	if (sector & (zone_sectors - 1))
		return -EINVAL;

	if ((nr_sectors & (zone_sectors - 1)) &&
	    end_sector != bdev->bd_part->nr_sects)
		return -EINVAL;

	while (sector < end_sector) {

		bio = bio_alloc(gfp_mask, 0);
		bio->bi_iter.bi_sector = sector;
		bio_set_dev(bio, bdev);
		bio_set_op_attrs(bio, REQ_OP_ZONE_RESET, 0);

		ret = submit_bio_wait(bio);
		bio_put(bio);

		if (ret)
			return ret;

		sector += zone_sectors;

		/* This may take a while, so be nice to others */
		cond_resched();

	}

	return 0;
}
EXPORT_SYMBOL_GPL(blkdev_reset_zones);

/*
 * BLKREPORTZONE ioctl processing.
 * Called from blkdev_ioctl.
 */
int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode,
			      unsigned int cmd, unsigned long arg)
{
	void __user *argp = (void __user *)arg;
	struct request_queue *q;
	struct blk_zone_report rep;
	struct blk_zone *zones;
	int ret;

	if (!argp)
		return -EINVAL;

	q = bdev_get_queue(bdev);
	if (!q)
		return -ENXIO;

	if (!blk_queue_is_zoned(q))
		return -ENOTTY;

	if (!capable(CAP_SYS_ADMIN))
		return -EACCES;

	if (copy_from_user(&rep, argp, sizeof(struct blk_zone_report)))
		return -EFAULT;

	if (!rep.nr_zones)
		return -EINVAL;

	if (rep.nr_zones > INT_MAX / sizeof(struct blk_zone))
		return -ERANGE;

	zones = kvmalloc_array(rep.nr_zones, sizeof(struct blk_zone),
			       GFP_KERNEL | __GFP_ZERO);
	if (!zones)
		return -ENOMEM;

	ret = blkdev_report_zones(bdev, rep.sector,
				  zones, &rep.nr_zones,
				  GFP_KERNEL);
	if (ret)
		goto out;

	if (copy_to_user(argp, &rep, sizeof(struct blk_zone_report))) {
		ret = -EFAULT;
		goto out;
	}

	if (rep.nr_zones) {
		if (copy_to_user(argp + sizeof(struct blk_zone_report), zones,
				 sizeof(struct blk_zone) * rep.nr_zones))
			ret = -EFAULT;
	}

 out:
	kvfree(zones);

	return ret;
}

/*
 * BLKRESETZONE ioctl processing.
 * Called from blkdev_ioctl.
 */
int blkdev_reset_zones_ioctl(struct block_device *bdev, fmode_t mode,
			     unsigned int cmd, unsigned long arg)
{
	void __user *argp = (void __user *)arg;
	struct request_queue *q;
	struct blk_zone_range zrange;

	if (!argp)
		return -EINVAL;

	q = bdev_get_queue(bdev);
	if (!q)
		return -ENXIO;

	if (!blk_queue_is_zoned(q))
		return -ENOTTY;

	if (!capable(CAP_SYS_ADMIN))
		return -EACCES;

	if (!(mode & FMODE_WRITE))
		return -EBADF;

	if (copy_from_user(&zrange, argp, sizeof(struct blk_zone_range)))
		return -EFAULT;

	return blkdev_reset_zones(bdev, zrange.sector, zrange.nr_sectors,
				  GFP_KERNEL);
}
Commit	Line	Data
6a0cb1bc HR	1	/*
	2	* Zoned block device handling
	3	*
	4	* Copyright (c) 2015, Hannes Reinecke
	5	* Copyright (c) 2015, SUSE Linux GmbH
	6	*
	7	* Copyright (c) 2016, Damien Le Moal
	8	* Copyright (c) 2016, Western Digital
	9	*/
	10
	11	#include <linux/kernel.h>
	12	#include <linux/module.h>
	13	#include <linux/rbtree.h>
	14	#include <linux/blkdev.h>
	15
	16	static inline sector_t blk_zone_start(struct request_queue *q,
	17	sector_t sector)
	18	{
f99e8648	19	sector_t zone_mask = blk_queue_zone_sectors(q) - 1;
6a0cb1bc HR	20
	21	return sector & ~zone_mask;
	22	}
	23
6cc77e9c CH	24	/*
	25	* Return true if a request is a write requests that needs zone write locking.
	26	*/
	27	bool blk_req_needs_zone_write_lock(struct request *rq)
	28	{
	29	if (!rq->q->seq_zones_wlock)
	30	return false;
	31
	32	if (blk_rq_is_passthrough(rq))
	33	return false;
	34
	35	switch (req_op(rq)) {
	36	case REQ_OP_WRITE_ZEROES:
	37	case REQ_OP_WRITE_SAME:
	38	case REQ_OP_WRITE:
	39	return blk_rq_zone_is_seq(rq);
	40	default:
	41	return false;
	42	}
	43	}
	44	EXPORT_SYMBOL_GPL(blk_req_needs_zone_write_lock);
	45
	46	void __blk_req_zone_write_lock(struct request *rq)
	47	{
	48	if (WARN_ON_ONCE(test_and_set_bit(blk_rq_zone_no(rq),
	49	rq->q->seq_zones_wlock)))
	50	return;
	51
	52	WARN_ON_ONCE(rq->rq_flags & RQF_ZONE_WRITE_LOCKED);
	53	rq->rq_flags \|= RQF_ZONE_WRITE_LOCKED;
	54	}
	55	EXPORT_SYMBOL_GPL(__blk_req_zone_write_lock);
	56
	57	void __blk_req_zone_write_unlock(struct request *rq)
	58	{
	59	rq->rq_flags &= ~RQF_ZONE_WRITE_LOCKED;
	60	if (rq->q->seq_zones_wlock)
	61	WARN_ON_ONCE(!test_and_clear_bit(blk_rq_zone_no(rq),
	62	rq->q->seq_zones_wlock));
	63	}
	64	EXPORT_SYMBOL_GPL(__blk_req_zone_write_unlock);
	65
6a0cb1bc HR	66	/*
	67	* Check that a zone report belongs to the partition.
	68	* If yes, fix its start sector and write pointer, copy it in the
	69	* zone information array and return true. Return false otherwise.
	70	*/
	71	static bool blkdev_report_zone(struct block_device *bdev,
	72	struct blk_zone *rep,
	73	struct blk_zone *zone)
	74	{
	75	sector_t offset = get_start_sect(bdev);
	76
	77	if (rep->start < offset)
	78	return false;
	79
	80	rep->start -= offset;
	81	if (rep->start + rep->len > bdev->bd_part->nr_sects)
	82	return false;
	83
	84	if (rep->type == BLK_ZONE_TYPE_CONVENTIONAL)
	85	rep->wp = rep->start + rep->len;
	86	else
	87	rep->wp -= offset;
	88	memcpy(zone, rep, sizeof(struct blk_zone));
	89
	90	return true;
	91	}
	92
	93	/**
	94	* blkdev_report_zones - Get zones information
	95	* @bdev: Target block device
	96	* @sector: Sector from which to report zones
	97	* @zones: Array of zone structures where to return the zones information
	98	* @nr_zones: Number of zone structures in the zone array
	99	* @gfp_mask: Memory allocation flags (for bio_alloc)
	100	*
	101	* Description:
	102	* Get zone information starting from the zone containing @sector.
	103	* The number of zone information reported may be less than the number
	104	* requested by @nr_zones. The number of zones actually reported is
	105	* returned in @nr_zones.
	106	*/
	107	int blkdev_report_zones(struct block_device *bdev,
	108	sector_t sector,
	109	struct blk_zone *zones,
	110	unsigned int *nr_zones,
	111	gfp_t gfp_mask)
	112	{
	113	struct request_queue *q = bdev_get_queue(bdev);
	114	struct blk_zone_report_hdr *hdr;
	115	unsigned int nrz = *nr_zones;
	116	struct page *page;
	117	unsigned int nr_rep;
	118	size_t rep_bytes;
	119	unsigned int nr_pages;
	120	struct bio *bio;
	121	struct bio_vec *bv;
	122	unsigned int i, n, nz;
	123	unsigned int ofst;
	124	void *addr;
3c4da758	125	int ret;
6a0cb1bc HR	126
	127	if (!q)
	128	return -ENXIO;
	129
	130	if (!blk_queue_is_zoned(q))
	131	return -EOPNOTSUPP;
	132
	133	if (!nrz)
	134	return 0;
	135
	136	if (sector > bdev->bd_part->nr_sects) {
	137	*nr_zones = 0;
	138	return 0;
	139	}
	140
	141	/*
	142	* The zone report has a header. So make room for it in the
	143	* payload. Also make sure that the report fits in a single BIO
	144	* that will not be split down the stack.
	145	*/
	146	rep_bytes = sizeof(struct blk_zone_report_hdr) +
	147	sizeof(struct blk_zone) * nrz;
	148	rep_bytes = (rep_bytes + PAGE_SIZE - 1) & PAGE_MASK;
	149	if (rep_bytes > (queue_max_sectors(q) << 9))
	150	rep_bytes = queue_max_sectors(q) << 9;
	151
	152	nr_pages = min_t(unsigned int, BIO_MAX_PAGES,
	153	rep_bytes >> PAGE_SHIFT);
	154	nr_pages = min_t(unsigned int, nr_pages,
	155	queue_max_segments(q));
	156
	157	bio = bio_alloc(gfp_mask, nr_pages);
	158	if (!bio)
	159	return -ENOMEM;
	160
74d46992	161	bio_set_dev(bio, bdev);
6a0cb1bc HR	162	bio->bi_iter.bi_sector = blk_zone_start(q, sector);
	163	bio_set_op_attrs(bio, REQ_OP_ZONE_REPORT, 0);
	164
	165	for (i = 0; i < nr_pages; i++) {
	166	page = alloc_page(gfp_mask);
	167	if (!page) {
	168	ret = -ENOMEM;
	169	goto out;
	170	}
	171	if (!bio_add_page(bio, page, PAGE_SIZE, 0)) {
	172	__free_page(page);
	173	break;
	174	}
	175	}
	176
	177	if (i == 0)
	178	ret = -ENOMEM;
	179	else
	180	ret = submit_bio_wait(bio);
	181	if (ret)
	182	goto out;
	183
	184	/*
	185	* Process the report result: skip the header and go through the
	186	* reported zones to fixup and fixup the zone information for
	187	* partitions. At the same time, return the zone information into
	188	* the zone array.
	189	*/
	190	n = 0;
	191	nz = 0;
	192	nr_rep = 0;
	193	bio_for_each_segment_all(bv, bio, i) {
	194
	195	if (!bv->bv_page)
	196	break;
	197
	198	addr = kmap_atomic(bv->bv_page);
	199
	200	/* Get header in the first page */
	201	ofst = 0;
	202	if (!nr_rep) {
	203	hdr = (struct blk_zone_report_hdr *) addr;
	204	nr_rep = hdr->nr_zones;
	205	ofst = sizeof(struct blk_zone_report_hdr);
	206	}
	207
	208	/* Fixup and report zones */
	209	while (ofst < bv->bv_len &&
	210	n < nr_rep && nz < nrz) {
	211	if (blkdev_report_zone(bdev, addr + ofst, &zones[nz]))
	212	nz++;
	213	ofst += sizeof(struct blk_zone);
	214	n++;
	215	}
	216
	217	kunmap_atomic(addr);
	218
	219	if (n >= nr_rep \|\| nz >= nrz)
	220	break;
	221
	222	}
	223
3c4da758	224	*nr_zones = nz;
6a0cb1bc HR	225	out:
	226	bio_for_each_segment_all(bv, bio, i)
	227	__free_page(bv->bv_page);
	228	bio_put(bio);
	229
6a0cb1bc HR	230	return ret;
	231	}
	232	EXPORT_SYMBOL_GPL(blkdev_report_zones);
	233
	234	/**
	235	* blkdev_reset_zones - Reset zones write pointer
	236	* @bdev: Target block device
	237	* @sector: Start sector of the first zone to reset
	238	* @nr_sectors: Number of sectors, at least the length of one zone
	239	* @gfp_mask: Memory allocation flags (for bio_alloc)
	240	*
	241	* Description:
	242	* Reset the write pointer of the zones contained in the range
	243	* @sector..@sector+@nr_sectors. Specifying the entire disk sector range
	244	* is valid, but the specified range should not contain conventional zones.
	245	*/
	246	int blkdev_reset_zones(struct block_device *bdev,
	247	sector_t sector, sector_t nr_sectors,
	248	gfp_t gfp_mask)
	249	{
	250	struct request_queue *q = bdev_get_queue(bdev);
	251	sector_t zone_sectors;
	252	sector_t end_sector = sector + nr_sectors;
	253	struct bio *bio;
	254	int ret;
	255
	256	if (!q)
	257	return -ENXIO;
	258
	259	if (!blk_queue_is_zoned(q))
	260	return -EOPNOTSUPP;
	261
	262	if (end_sector > bdev->bd_part->nr_sects)
	263	/* Out of range */
	264	return -EINVAL;
	265
	266	/* Check alignment (handle eventual smaller last zone) */
f99e8648	267	zone_sectors = blk_queue_zone_sectors(q);
6a0cb1bc HR	268	if (sector & (zone_sectors - 1))
	269	return -EINVAL;
	270
	271	if ((nr_sectors & (zone_sectors - 1)) &&
	272	end_sector != bdev->bd_part->nr_sects)
	273	return -EINVAL;
	274
	275	while (sector < end_sector) {
	276
	277	bio = bio_alloc(gfp_mask, 0);
	278	bio->bi_iter.bi_sector = sector;
74d46992	279	bio_set_dev(bio, bdev);
6a0cb1bc HR	280	bio_set_op_attrs(bio, REQ_OP_ZONE_RESET, 0);
	281
	282	ret = submit_bio_wait(bio);
	283	bio_put(bio);
	284
	285	if (ret)
	286	return ret;
	287
	288	sector += zone_sectors;
	289
	290	/* This may take a while, so be nice to others */
	291	cond_resched();
	292
	293	}
	294
	295	return 0;
	296	}
	297	EXPORT_SYMBOL_GPL(blkdev_reset_zones);
3ed05a98	298
56c4bddb	299	/*
3ed05a98 ST	300	* BLKREPORTZONE ioctl processing.
	301	* Called from blkdev_ioctl.
	302	*/
	303	int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode,
	304	unsigned int cmd, unsigned long arg)
	305	{
	306	void __user argp = (void __user )arg;
	307	struct request_queue *q;
	308	struct blk_zone_report rep;
	309	struct blk_zone *zones;
	310	int ret;
	311
	312	if (!argp)
	313	return -EINVAL;
	314
	315	q = bdev_get_queue(bdev);
	316	if (!q)
	317	return -ENXIO;
	318
	319	if (!blk_queue_is_zoned(q))
	320	return -ENOTTY;
	321
	322	if (!capable(CAP_SYS_ADMIN))
	323	return -EACCES;
	324
	325	if (copy_from_user(&rep, argp, sizeof(struct blk_zone_report)))
	326	return -EFAULT;
	327
	328	if (!rep.nr_zones)
	329	return -EINVAL;
	330
327ea4ad BVA	331	if (rep.nr_zones > INT_MAX / sizeof(struct blk_zone))
	332	return -ERANGE;
	333
344476e1 KC	334	zones = kvmalloc_array(rep.nr_zones, sizeof(struct blk_zone),
344476e1 KC	335	GFP_KERNEL \| __GFP_ZERO);
3ed05a98 ST	336	if (!zones)
	337	return -ENOMEM;
	338
	339	ret = blkdev_report_zones(bdev, rep.sector,
	340	zones, &rep.nr_zones,
	341	GFP_KERNEL);
	342	if (ret)
	343	goto out;
	344
	345	if (copy_to_user(argp, &rep, sizeof(struct blk_zone_report))) {
	346	ret = -EFAULT;
	347	goto out;
	348	}
	349
	350	if (rep.nr_zones) {
	351	if (copy_to_user(argp + sizeof(struct blk_zone_report), zones,
	352	sizeof(struct blk_zone) * rep.nr_zones))
	353	ret = -EFAULT;
	354	}
	355
	356	out:
327ea4ad	357	kvfree(zones);
3ed05a98 ST	358
	359	return ret;
	360	}
	361
56c4bddb	362	/*
3ed05a98 ST	363	* BLKRESETZONE ioctl processing.
	364	* Called from blkdev_ioctl.
	365	*/
	366	int blkdev_reset_zones_ioctl(struct block_device *bdev, fmode_t mode,
	367	unsigned int cmd, unsigned long arg)
	368	{
	369	void __user argp = (void __user )arg;
	370	struct request_queue *q;
	371	struct blk_zone_range zrange;
	372
	373	if (!argp)
	374	return -EINVAL;
	375
	376	q = bdev_get_queue(bdev);
	377	if (!q)
	378	return -ENXIO;
	379
	380	if (!blk_queue_is_zoned(q))
	381	return -ENOTTY;
	382
	383	if (!capable(CAP_SYS_ADMIN))
	384	return -EACCES;
	385
	386	if (!(mode & FMODE_WRITE))
	387	return -EBADF;
	388
	389	if (copy_from_user(&zrange, argp, sizeof(struct blk_zone_range)))
	390	return -EFAULT;
	391
	392	return blkdev_reset_zones(bdev, zrange.sector, zrange.nr_sectors,
	393	GFP_KERNEL);
	394	}