[linux-2.6-block.git] / block / blk-lib.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Functions related to generic helpers functions
 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/bio.h>
#include <linux/blkdev.h>
#include <linux/scatterlist.h>

#include "blk.h"

static sector_t bio_discard_limit(struct block_device *bdev, sector_t sector)
{
	unsigned int discard_granularity = bdev_discard_granularity(bdev);
	sector_t granularity_aligned_sector;

	if (bdev_is_partition(bdev))
		sector += bdev->bd_start_sect;

	granularity_aligned_sector =
		round_up(sector, discard_granularity >> SECTOR_SHIFT);

	/*
	 * Make sure subsequent bios start aligned to the discard granularity if
	 * it needs to be split.
	 */
	if (granularity_aligned_sector != sector)
		return granularity_aligned_sector - sector;

	/*
	 * Align the bio size to the discard granularity to make splitting the bio
	 * at discard granularity boundaries easier in the driver if needed.
	 */
	return round_down(UINT_MAX, discard_granularity) >> SECTOR_SHIFT;
}

int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
		sector_t nr_sects, gfp_t gfp_mask, struct bio **biop)
{
	struct bio *bio = *biop;
	sector_t bs_mask;

	if (bdev_read_only(bdev))
		return -EPERM;
	if (!bdev_max_discard_sectors(bdev))
		return -EOPNOTSUPP;

	/* In case the discard granularity isn't set by buggy device driver */
	if (WARN_ON_ONCE(!bdev_discard_granularity(bdev))) {
		pr_err_ratelimited("%pg: Error: discard_granularity is 0.\n",
				   bdev);
		return -EOPNOTSUPP;
	}

	bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
	if ((sector | nr_sects) & bs_mask)
		return -EINVAL;

	if (!nr_sects)
		return -EINVAL;

	while (nr_sects) {
		sector_t req_sects =
			min(nr_sects, bio_discard_limit(bdev, sector));

		bio = blk_next_bio(bio, bdev, 0, REQ_OP_DISCARD, gfp_mask);
		bio->bi_iter.bi_sector = sector;
		bio->bi_iter.bi_size = req_sects << 9;
		sector += req_sects;
		nr_sects -= req_sects;

		/*
		 * We can loop for a long time in here, if someone does
		 * full device discards (like mkfs). Be nice and allow
		 * us to schedule out to avoid softlocking if preempt
		 * is disabled.
		 */
		cond_resched();
	}

	*biop = bio;
	return 0;
}
EXPORT_SYMBOL(__blkdev_issue_discard);

/**
 * blkdev_issue_discard - queue a discard
 * @bdev:	blockdev to issue discard for
 * @sector:	start sector
 * @nr_sects:	number of sectors to discard
 * @gfp_mask:	memory allocation flags (for bio_alloc)
 *
 * Description:
 *    Issue a discard request for the sectors in question.
 */
int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
		sector_t nr_sects, gfp_t gfp_mask)
{
	struct bio *bio = NULL;
	struct blk_plug plug;
	int ret;

	blk_start_plug(&plug);
	ret = __blkdev_issue_discard(bdev, sector, nr_sects, gfp_mask, &bio);
	if (!ret && bio) {
		ret = submit_bio_wait(bio);
		if (ret == -EOPNOTSUPP)
			ret = 0;
		bio_put(bio);
	}
	blk_finish_plug(&plug);

	return ret;
}
EXPORT_SYMBOL(blkdev_issue_discard);

static int __blkdev_issue_write_zeroes(struct block_device *bdev,
		sector_t sector, sector_t nr_sects, gfp_t gfp_mask,
		struct bio **biop, unsigned flags)
{
	struct bio *bio = *biop;
	unsigned int max_sectors;

	if (bdev_read_only(bdev))
		return -EPERM;

	/* Ensure that max_sectors doesn't overflow bi_size */
	max_sectors = bdev_write_zeroes_sectors(bdev);

	if (max_sectors == 0)
		return -EOPNOTSUPP;

	while (nr_sects) {
		unsigned int len = min_t(sector_t, nr_sects, max_sectors);

		bio = blk_next_bio(bio, bdev, 0, REQ_OP_WRITE_ZEROES, gfp_mask);
		bio->bi_iter.bi_sector = sector;
		if (flags & BLKDEV_ZERO_NOUNMAP)
			bio->bi_opf |= REQ_NOUNMAP;

		bio->bi_iter.bi_size = len << SECTOR_SHIFT;
		nr_sects -= len;
		sector += len;
		cond_resched();
	}

	*biop = bio;
	return 0;
}

/*
 * Convert a number of 512B sectors to a number of pages.
 * The result is limited to a number of pages that can fit into a BIO.
 * Also make sure that the result is always at least 1 (page) for the cases
 * where nr_sects is lower than the number of sectors in a page.
 */
static unsigned int __blkdev_sectors_to_bio_pages(sector_t nr_sects)
{
	sector_t pages = DIV_ROUND_UP_SECTOR_T(nr_sects, PAGE_SIZE / 512);

	return min(pages, (sector_t)BIO_MAX_VECS);
}

static int __blkdev_issue_zero_pages(struct block_device *bdev,
		sector_t sector, sector_t nr_sects, gfp_t gfp_mask,
		struct bio **biop)
{
	struct bio *bio = *biop;
	int bi_size = 0;
	unsigned int sz;

	if (bdev_read_only(bdev))
		return -EPERM;

	while (nr_sects != 0) {
		bio = blk_next_bio(bio, bdev, __blkdev_sectors_to_bio_pages(nr_sects),
				   REQ_OP_WRITE, gfp_mask);
		bio->bi_iter.bi_sector = sector;

		while (nr_sects != 0) {
			sz = min((sector_t) PAGE_SIZE, nr_sects << 9);
			bi_size = bio_add_page(bio, ZERO_PAGE(0), sz, 0);
			nr_sects -= bi_size >> 9;
			sector += bi_size >> 9;
			if (bi_size < sz)
				break;
		}
		cond_resched();
	}

	*biop = bio;
	return 0;
}

/**
 * __blkdev_issue_zeroout - generate number of zero filed write bios
 * @bdev:	blockdev to issue
 * @sector:	start sector
 * @nr_sects:	number of sectors to write
 * @gfp_mask:	memory allocation flags (for bio_alloc)
 * @biop:	pointer to anchor bio
 * @flags:	controls detailed behavior
 *
 * Description:
 *  Zero-fill a block range, either using hardware offload or by explicitly
 *  writing zeroes to the device.
 *
 *  If a device is using logical block provisioning, the underlying space will
 *  not be released if %flags contains BLKDEV_ZERO_NOUNMAP.
 *
 *  If %flags contains BLKDEV_ZERO_NOFALLBACK, the function will return
 *  -EOPNOTSUPP if no explicit hardware offload for zeroing is provided.
 */
int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
		sector_t nr_sects, gfp_t gfp_mask, struct bio **biop,
		unsigned flags)
{
	int ret;
	sector_t bs_mask;

	bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
	if ((sector | nr_sects) & bs_mask)
		return -EINVAL;

	ret = __blkdev_issue_write_zeroes(bdev, sector, nr_sects, gfp_mask,
			biop, flags);
	if (ret != -EOPNOTSUPP || (flags & BLKDEV_ZERO_NOFALLBACK))
		return ret;

	return __blkdev_issue_zero_pages(bdev, sector, nr_sects, gfp_mask,
					 biop);
}
EXPORT_SYMBOL(__blkdev_issue_zeroout);

/**
 * blkdev_issue_zeroout - zero-fill a block range
 * @bdev:	blockdev to write
 * @sector:	start sector
 * @nr_sects:	number of sectors to write
 * @gfp_mask:	memory allocation flags (for bio_alloc)
 * @flags:	controls detailed behavior
 *
 * Description:
 *  Zero-fill a block range, either using hardware offload or by explicitly
 *  writing zeroes to the device.  See __blkdev_issue_zeroout() for the
 *  valid values for %flags.
 */
int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
		sector_t nr_sects, gfp_t gfp_mask, unsigned flags)
{
	int ret = 0;
	sector_t bs_mask;
	struct bio *bio;
	struct blk_plug plug;
	bool try_write_zeroes = !!bdev_write_zeroes_sectors(bdev);

	bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
	if ((sector | nr_sects) & bs_mask)
		return -EINVAL;

retry:
	bio = NULL;
	blk_start_plug(&plug);
	if (try_write_zeroes) {
		ret = __blkdev_issue_write_zeroes(bdev, sector, nr_sects,
						  gfp_mask, &bio, flags);
	} else if (!(flags & BLKDEV_ZERO_NOFALLBACK)) {
		ret = __blkdev_issue_zero_pages(bdev, sector, nr_sects,
						gfp_mask, &bio);
	} else {
		/* No zeroing offload support */
		ret = -EOPNOTSUPP;
	}
	if (ret == 0 && bio) {
		ret = submit_bio_wait(bio);
		bio_put(bio);
	}
	blk_finish_plug(&plug);
	if (ret && try_write_zeroes) {
		if (!(flags & BLKDEV_ZERO_NOFALLBACK)) {
			try_write_zeroes = false;
			goto retry;
		}
		if (!bdev_write_zeroes_sectors(bdev)) {
			/*
			 * Zeroing offload support was indicated, but the
			 * device reported ILLEGAL REQUEST (for some devices
			 * there is no non-destructive way to verify whether
			 * WRITE ZEROES is actually supported).
			 */
			ret = -EOPNOTSUPP;
		}
	}

	return ret;
}
EXPORT_SYMBOL(blkdev_issue_zeroout);

int blkdev_issue_secure_erase(struct block_device *bdev, sector_t sector,
		sector_t nr_sects, gfp_t gfp)
{
	sector_t bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
	unsigned int max_sectors = bdev_max_secure_erase_sectors(bdev);
	struct bio *bio = NULL;
	struct blk_plug plug;
	int ret = 0;

	/* make sure that "len << SECTOR_SHIFT" doesn't overflow */
	if (max_sectors > UINT_MAX >> SECTOR_SHIFT)
		max_sectors = UINT_MAX >> SECTOR_SHIFT;
	max_sectors &= ~bs_mask;

	if (max_sectors == 0)
		return -EOPNOTSUPP;
	if ((sector | nr_sects) & bs_mask)
		return -EINVAL;
	if (bdev_read_only(bdev))
		return -EPERM;

	blk_start_plug(&plug);
	while (nr_sects) {
		unsigned int len = min_t(sector_t, nr_sects, max_sectors);

		bio = blk_next_bio(bio, bdev, 0, REQ_OP_SECURE_ERASE, gfp);
		bio->bi_iter.bi_sector = sector;
		bio->bi_iter.bi_size = len << SECTOR_SHIFT;

		sector += len;
		nr_sects -= len;
		cond_resched();
	}
	if (bio) {
		ret = submit_bio_wait(bio);
		bio_put(bio);
	}
	blk_finish_plug(&plug);

	return ret;
}
EXPORT_SYMBOL(blkdev_issue_secure_erase);
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
f31e7e40 DM	2	/*
	3	* Functions related to generic helpers functions
	4	*/
	5	#include <linux/kernel.h>
	6	#include <linux/module.h>
	7	#include <linux/bio.h>
	8	#include <linux/blkdev.h>
	9	#include <linux/scatterlist.h>
	10
	11	#include "blk.h"
	12
e3cc28ea CH	13	static sector_t bio_discard_limit(struct block_device *bdev, sector_t sector)
e3cc28ea CH	14	{
7b47ef52	15	unsigned int discard_granularity = bdev_discard_granularity(bdev);
e3cc28ea CH	16	sector_t granularity_aligned_sector;
	17
	18	if (bdev_is_partition(bdev))
	19	sector += bdev->bd_start_sect;
	20
	21	granularity_aligned_sector =
	22	round_up(sector, discard_granularity >> SECTOR_SHIFT);
	23
	24	/*
	25	* Make sure subsequent bios start aligned to the discard granularity if
	26	* it needs to be split.
	27	*/
	28	if (granularity_aligned_sector != sector)
	29	return granularity_aligned_sector - sector;
	30
	31	/*
	32	* Align the bio size to the discard granularity to make splitting the bio
	33	* at discard granularity boundaries easier in the driver if needed.
	34	*/
	35	return round_down(UINT_MAX, discard_granularity) >> SECTOR_SHIFT;
	36	}
	37
38f25255	38	int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
44abff2c	39	sector_t nr_sects, gfp_t gfp_mask, struct bio **biop)
f31e7e40	40	{
38f25255	41	struct bio bio = biop;
e3cc28ea	42	sector_t bs_mask;
f31e7e40	43
a13553c7 ID	44	if (bdev_read_only(bdev))
a13553c7 ID	45	return -EPERM;
44abff2c CH	46	if (!bdev_max_discard_sectors(bdev))
44abff2c CH	47	return -EOPNOTSUPP;
f31e7e40	48
b35fd742	49	/* In case the discard granularity isn't set by buggy device driver */
7b47ef52	50	if (WARN_ON_ONCE(!bdev_discard_granularity(bdev))) {
02ff3dd2 CH	51	pr_err_ratelimited("%pg: Error: discard_granularity is 0.\n",
02ff3dd2 CH	52	bdev);
b35fd742 CL	53	return -EOPNOTSUPP;
	54	}
	55
28b2be20 DW	56	bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
	57	if ((sector \| nr_sects) & bs_mask)
	58	return -EINVAL;
	59
ba5d7385 ML	60	if (!nr_sects)
ba5d7385 ML	61	return -EINVAL;
a22c4d7e	62
ba5d7385	63	while (nr_sects) {
e3cc28ea CH	64	sector_t req_sects =
e3cc28ea CH	65	min(nr_sects, bio_discard_limit(bdev, sector));
4800bf7b	66
44abff2c	67	bio = blk_next_bio(bio, bdev, 0, REQ_OP_DISCARD, gfp_mask);
4f024f37	68	bio->bi_iter.bi_sector = sector;
4f024f37	69	bio->bi_iter.bi_size = req_sects << 9;
ba5d7385	70	sector += req_sects;
c6e66634	71	nr_sects -= req_sects;
f31e7e40	72
c8123f8c JA	73	/*
	74	* We can loop for a long time in here, if someone does
	75	* full device discards (like mkfs). Be nice and allow
	76	* us to schedule out to avoid softlocking if preempt
	77	* is disabled.
	78	*/
	79	cond_resched();
5dba3089	80	}
38f25255 CH	81
	82	*biop = bio;
	83	return 0;
	84	}
	85	EXPORT_SYMBOL(__blkdev_issue_discard);
	86
	87	/**
	88	* blkdev_issue_discard - queue a discard
	89	* @bdev: blockdev to issue discard for
	90	* @sector: start sector
	91	* @nr_sects: number of sectors to discard
	92	* @gfp_mask: memory allocation flags (for bio_alloc)
38f25255 CH	93	*
	94	* Description:
	95	* Issue a discard request for the sectors in question.
	96	*/
	97	int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
44abff2c	98	sector_t nr_sects, gfp_t gfp_mask)
38f25255	99	{
38f25255 CH	100	struct bio *bio = NULL;
	101	struct blk_plug plug;
	102	int ret;
	103
38f25255	104	blk_start_plug(&plug);
44abff2c	105	ret = __blkdev_issue_discard(bdev, sector, nr_sects, gfp_mask, &bio);
bbd848e0	106	if (!ret && bio) {
4e49ea4a	107	ret = submit_bio_wait(bio);
48920ff2	108	if (ret == -EOPNOTSUPP)
bbd848e0	109	ret = 0;
05bd92dd	110	bio_put(bio);
bbd848e0	111	}
0cfbcafc	112	blk_finish_plug(&plug);
f31e7e40	113
bbd848e0	114	return ret;
f31e7e40 DM	115	}
f31e7e40 DM	116	EXPORT_SYMBOL(blkdev_issue_discard);
3f14d792	117
a6f0788e CK	118	static int __blkdev_issue_write_zeroes(struct block_device *bdev,
a6f0788e CK	119	sector_t sector, sector_t nr_sects, gfp_t gfp_mask,
d928be9f	120	struct bio **biop, unsigned flags)
a6f0788e CK	121	{
a6f0788e CK	122	struct bio bio = biop;
76a27e1b	123	unsigned int max_sectors;
a6f0788e	124
a13553c7 ID	125	if (bdev_read_only(bdev))
	126	return -EPERM;
	127
76a27e1b KB	128	/* Ensure that max_sectors doesn't overflow bi_size */
76a27e1b KB	129	max_sectors = bdev_write_zeroes_sectors(bdev);
a6f0788e	130
76a27e1b	131	if (max_sectors == 0)
a6f0788e CK	132	return -EOPNOTSUPP;
	133
	134	while (nr_sects) {
76a27e1b KB	135	unsigned int len = min_t(sector_t, nr_sects, max_sectors);
76a27e1b KB	136
0a3140ea	137	bio = blk_next_bio(bio, bdev, 0, REQ_OP_WRITE_ZEROES, gfp_mask);
a6f0788e	138	bio->bi_iter.bi_sector = sector;
d928be9f CH	139	if (flags & BLKDEV_ZERO_NOUNMAP)
d928be9f CH	140	bio->bi_opf \|= REQ_NOUNMAP;
a6f0788e	141
76a27e1b KB	142	bio->bi_iter.bi_size = len << SECTOR_SHIFT;
	143	nr_sects -= len;
	144	sector += len;
a6f0788e CK	145	cond_resched();
	146	}
	147
	148	*biop = bio;
	149	return 0;
	150	}
	151
615d22a5 DLM	152	/*
	153	* Convert a number of 512B sectors to a number of pages.
	154	* The result is limited to a number of pages that can fit into a BIO.
	155	* Also make sure that the result is always at least 1 (page) for the cases
	156	* where nr_sects is lower than the number of sectors in a page.
	157	*/
	158	static unsigned int __blkdev_sectors_to_bio_pages(sector_t nr_sects)
	159	{
09c2c359	160	sector_t pages = DIV_ROUND_UP_SECTOR_T(nr_sects, PAGE_SIZE / 512);
615d22a5	161
a8affc03	162	return min(pages, (sector_t)BIO_MAX_VECS);
615d22a5 DLM	163	}
615d22a5 DLM	164
425a4dba ID	165	static int __blkdev_issue_zero_pages(struct block_device *bdev,
	166	sector_t sector, sector_t nr_sects, gfp_t gfp_mask,
	167	struct bio **biop)
	168	{
425a4dba ID	169	struct bio bio = biop;
	170	int bi_size = 0;
	171	unsigned int sz;
	172
a13553c7 ID	173	if (bdev_read_only(bdev))
	174	return -EPERM;
	175
425a4dba	176	while (nr_sects != 0) {
0a3140ea CK	177	bio = blk_next_bio(bio, bdev, __blkdev_sectors_to_bio_pages(nr_sects),
0a3140ea CK	178	REQ_OP_WRITE, gfp_mask);
425a4dba	179	bio->bi_iter.bi_sector = sector;
425a4dba ID	180
	181	while (nr_sects != 0) {
	182	sz = min((sector_t) PAGE_SIZE, nr_sects << 9);
	183	bi_size = bio_add_page(bio, ZERO_PAGE(0), sz, 0);
	184	nr_sects -= bi_size >> 9;
	185	sector += bi_size >> 9;
	186	if (bi_size < sz)
	187	break;
	188	}
	189	cond_resched();
	190	}
	191
	192	*biop = bio;
	193	return 0;
	194	}
	195
3f14d792	196	/**
e73c23ff	197	* __blkdev_issue_zeroout - generate number of zero filed write bios
3f14d792 DM	198	* @bdev: blockdev to issue
	199	* @sector: start sector
	200	* @nr_sects: number of sectors to write
	201	* @gfp_mask: memory allocation flags (for bio_alloc)
e73c23ff	202	* @biop: pointer to anchor bio
ee472d83	203	* @flags: controls detailed behavior
3f14d792 DM	204	*
3f14d792 DM	205	* Description:
ee472d83 CH	206	* Zero-fill a block range, either using hardware offload or by explicitly
	207	* writing zeroes to the device.
	208	*
	209	* If a device is using logical block provisioning, the underlying space will
	210	* not be released if %flags contains BLKDEV_ZERO_NOUNMAP.
cb365b96 CH	211	*
	212	* If %flags contains BLKDEV_ZERO_NOFALLBACK, the function will return
	213	* -EOPNOTSUPP if no explicit hardware offload for zeroing is provided.
3f14d792	214	*/
e73c23ff CK	215	int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
e73c23ff CK	216	sector_t nr_sects, gfp_t gfp_mask, struct bio **biop,
ee472d83	217	unsigned flags)
3f14d792	218	{
18edc8ea	219	int ret;
28b2be20 DW	220	sector_t bs_mask;
	221
	222	bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
	223	if ((sector \| nr_sects) & bs_mask)
	224	return -EINVAL;
3f14d792	225
a6f0788e	226	ret = __blkdev_issue_write_zeroes(bdev, sector, nr_sects, gfp_mask,
d928be9f	227	biop, flags);
cb365b96	228	if (ret != -EOPNOTSUPP \|\| (flags & BLKDEV_ZERO_NOFALLBACK))
425a4dba	229	return ret;
3f14d792	230
425a4dba ID	231	return __blkdev_issue_zero_pages(bdev, sector, nr_sects, gfp_mask,
425a4dba ID	232	biop);
3f14d792	233	}
e73c23ff	234	EXPORT_SYMBOL(__blkdev_issue_zeroout);
579e8f3c MP	235
	236	/**
	237	* blkdev_issue_zeroout - zero-fill a block range
	238	* @bdev: blockdev to write
	239	* @sector: start sector
	240	* @nr_sects: number of sectors to write
	241	* @gfp_mask: memory allocation flags (for bio_alloc)
ee472d83	242	* @flags: controls detailed behavior
579e8f3c MP	243	*
579e8f3c MP	244	* Description:
ee472d83 CH	245	* Zero-fill a block range, either using hardware offload or by explicitly
	246	* writing zeroes to the device. See __blkdev_issue_zeroout() for the
	247	* valid values for %flags.
579e8f3c	248	*/
579e8f3c	249	int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
ee472d83	250	sector_t nr_sects, gfp_t gfp_mask, unsigned flags)
579e8f3c	251	{
d5ce4c31 ID	252	int ret = 0;
	253	sector_t bs_mask;
	254	struct bio *bio;
e73c23ff	255	struct blk_plug plug;
d5ce4c31	256	bool try_write_zeroes = !!bdev_write_zeroes_sectors(bdev);
d93ba7a5	257
d5ce4c31 ID	258	bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
	259	if ((sector \| nr_sects) & bs_mask)
	260	return -EINVAL;
	261
	262	retry:
	263	bio = NULL;
e73c23ff	264	blk_start_plug(&plug);
d5ce4c31 ID	265	if (try_write_zeroes) {
	266	ret = __blkdev_issue_write_zeroes(bdev, sector, nr_sects,
	267	gfp_mask, &bio, flags);
	268	} else if (!(flags & BLKDEV_ZERO_NOFALLBACK)) {
	269	ret = __blkdev_issue_zero_pages(bdev, sector, nr_sects,
	270	gfp_mask, &bio);
	271	} else {
	272	/* No zeroing offload support */
	273	ret = -EOPNOTSUPP;
	274	}
e73c23ff CK	275	if (ret == 0 && bio) {
	276	ret = submit_bio_wait(bio);
	277	bio_put(bio);
	278	}
	279	blk_finish_plug(&plug);
d5ce4c31 ID	280	if (ret && try_write_zeroes) {
	281	if (!(flags & BLKDEV_ZERO_NOFALLBACK)) {
	282	try_write_zeroes = false;
	283	goto retry;
	284	}
	285	if (!bdev_write_zeroes_sectors(bdev)) {
	286	/*
	287	* Zeroing offload support was indicated, but the
	288	* device reported ILLEGAL REQUEST (for some devices
	289	* there is no non-destructive way to verify whether
	290	* WRITE ZEROES is actually supported).
	291	*/
	292	ret = -EOPNOTSUPP;
	293	}
	294	}
579e8f3c	295
e73c23ff	296	return ret;
579e8f3c	297	}
3f14d792	298	EXPORT_SYMBOL(blkdev_issue_zeroout);
44abff2c CH	299
	300	int blkdev_issue_secure_erase(struct block_device *bdev, sector_t sector,
	301	sector_t nr_sects, gfp_t gfp)
	302	{
	303	sector_t bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
	304	unsigned int max_sectors = bdev_max_secure_erase_sectors(bdev);
	305	struct bio *bio = NULL;
	306	struct blk_plug plug;
	307	int ret = 0;
	308
c4fa3684 MP	309	/* make sure that "len << SECTOR_SHIFT" doesn't overflow */
	310	if (max_sectors > UINT_MAX >> SECTOR_SHIFT)
	311	max_sectors = UINT_MAX >> SECTOR_SHIFT;
	312	max_sectors &= ~bs_mask;
	313
44abff2c CH	314	if (max_sectors == 0)
	315	return -EOPNOTSUPP;
	316	if ((sector \| nr_sects) & bs_mask)
	317	return -EINVAL;
	318	if (bdev_read_only(bdev))
	319	return -EPERM;
	320
	321	blk_start_plug(&plug);
5affe497	322	while (nr_sects) {
44abff2c CH	323	unsigned int len = min_t(sector_t, nr_sects, max_sectors);
	324
	325	bio = blk_next_bio(bio, bdev, 0, REQ_OP_SECURE_ERASE, gfp);
	326	bio->bi_iter.bi_sector = sector;
c4fa3684	327	bio->bi_iter.bi_size = len << SECTOR_SHIFT;
44abff2c	328
c4fa3684 MP	329	sector += len;
c4fa3684 MP	330	nr_sects -= len;
44abff2c CH	331	cond_resched();
44abff2c CH	332	}
5affe497 KB	333	if (bio) {
	334	ret = submit_bio_wait(bio);
	335	bio_put(bio);
	336	}
44abff2c CH	337	blk_finish_plug(&plug);
	338
	339	return ret;
	340	}
	341	EXPORT_SYMBOL(blkdev_issue_secure_erase);