[linux-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;

	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
28b2be20 DW	49	bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
	50	if ((sector \| nr_sects) & bs_mask)
	51	return -EINVAL;
	52
ba5d7385 ML	53	if (!nr_sects)
ba5d7385 ML	54	return -EINVAL;
a22c4d7e	55
ba5d7385	56	while (nr_sects) {
e3cc28ea CH	57	sector_t req_sects =
e3cc28ea CH	58	min(nr_sects, bio_discard_limit(bdev, sector));
4800bf7b	59
44abff2c	60	bio = blk_next_bio(bio, bdev, 0, REQ_OP_DISCARD, gfp_mask);
4f024f37	61	bio->bi_iter.bi_sector = sector;
4f024f37	62	bio->bi_iter.bi_size = req_sects << 9;
ba5d7385	63	sector += req_sects;
c6e66634	64	nr_sects -= req_sects;
f31e7e40	65
c8123f8c JA	66	/*
	67	* We can loop for a long time in here, if someone does
	68	* full device discards (like mkfs). Be nice and allow
	69	* us to schedule out to avoid softlocking if preempt
	70	* is disabled.
	71	*/
	72	cond_resched();
5dba3089	73	}
38f25255 CH	74
	75	*biop = bio;
	76	return 0;
	77	}
	78	EXPORT_SYMBOL(__blkdev_issue_discard);
	79
	80	/**
	81	* blkdev_issue_discard - queue a discard
	82	* @bdev: blockdev to issue discard for
	83	* @sector: start sector
	84	* @nr_sects: number of sectors to discard
	85	* @gfp_mask: memory allocation flags (for bio_alloc)
38f25255 CH	86	*
	87	* Description:
	88	* Issue a discard request for the sectors in question.
	89	*/
	90	int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
44abff2c	91	sector_t nr_sects, gfp_t gfp_mask)
38f25255	92	{
38f25255 CH	93	struct bio *bio = NULL;
	94	struct blk_plug plug;
	95	int ret;
	96
38f25255	97	blk_start_plug(&plug);
44abff2c	98	ret = __blkdev_issue_discard(bdev, sector, nr_sects, gfp_mask, &bio);
bbd848e0	99	if (!ret && bio) {
4e49ea4a	100	ret = submit_bio_wait(bio);
48920ff2	101	if (ret == -EOPNOTSUPP)
bbd848e0	102	ret = 0;
05bd92dd	103	bio_put(bio);
bbd848e0	104	}
0cfbcafc	105	blk_finish_plug(&plug);
f31e7e40	106
bbd848e0	107	return ret;
f31e7e40 DM	108	}
f31e7e40 DM	109	EXPORT_SYMBOL(blkdev_issue_discard);
3f14d792	110
a6f0788e CK	111	static int __blkdev_issue_write_zeroes(struct block_device *bdev,
a6f0788e CK	112	sector_t sector, sector_t nr_sects, gfp_t gfp_mask,
d928be9f	113	struct bio **biop, unsigned flags)
a6f0788e CK	114	{
a6f0788e CK	115	struct bio bio = biop;
76a27e1b	116	unsigned int max_sectors;
a6f0788e	117
a13553c7 ID	118	if (bdev_read_only(bdev))
	119	return -EPERM;
	120
76a27e1b KB	121	/* Ensure that max_sectors doesn't overflow bi_size */
76a27e1b KB	122	max_sectors = bdev_write_zeroes_sectors(bdev);
a6f0788e	123
76a27e1b	124	if (max_sectors == 0)
a6f0788e CK	125	return -EOPNOTSUPP;
	126
	127	while (nr_sects) {
76a27e1b KB	128	unsigned int len = min_t(sector_t, nr_sects, max_sectors);
76a27e1b KB	129
0a3140ea	130	bio = blk_next_bio(bio, bdev, 0, REQ_OP_WRITE_ZEROES, gfp_mask);
a6f0788e	131	bio->bi_iter.bi_sector = sector;
d928be9f CH	132	if (flags & BLKDEV_ZERO_NOUNMAP)
d928be9f CH	133	bio->bi_opf \|= REQ_NOUNMAP;
a6f0788e	134
76a27e1b KB	135	bio->bi_iter.bi_size = len << SECTOR_SHIFT;
	136	nr_sects -= len;
	137	sector += len;
a6f0788e CK	138	cond_resched();
	139	}
	140
	141	*biop = bio;
	142	return 0;
	143	}
	144
615d22a5 DLM	145	/*
	146	* Convert a number of 512B sectors to a number of pages.
	147	* The result is limited to a number of pages that can fit into a BIO.
	148	* Also make sure that the result is always at least 1 (page) for the cases
	149	* where nr_sects is lower than the number of sectors in a page.
	150	*/
	151	static unsigned int __blkdev_sectors_to_bio_pages(sector_t nr_sects)
	152	{
09c2c359	153	sector_t pages = DIV_ROUND_UP_SECTOR_T(nr_sects, PAGE_SIZE / 512);
615d22a5	154
a8affc03	155	return min(pages, (sector_t)BIO_MAX_VECS);
615d22a5 DLM	156	}
615d22a5 DLM	157
425a4dba ID	158	static int __blkdev_issue_zero_pages(struct block_device *bdev,
	159	sector_t sector, sector_t nr_sects, gfp_t gfp_mask,
	160	struct bio **biop)
	161	{
425a4dba ID	162	struct bio bio = biop;
	163	int bi_size = 0;
	164	unsigned int sz;
	165
a13553c7 ID	166	if (bdev_read_only(bdev))
	167	return -EPERM;
	168
425a4dba	169	while (nr_sects != 0) {
0a3140ea CK	170	bio = blk_next_bio(bio, bdev, __blkdev_sectors_to_bio_pages(nr_sects),
0a3140ea CK	171	REQ_OP_WRITE, gfp_mask);
425a4dba	172	bio->bi_iter.bi_sector = sector;
425a4dba ID	173
	174	while (nr_sects != 0) {
	175	sz = min((sector_t) PAGE_SIZE, nr_sects << 9);
	176	bi_size = bio_add_page(bio, ZERO_PAGE(0), sz, 0);
	177	nr_sects -= bi_size >> 9;
	178	sector += bi_size >> 9;
	179	if (bi_size < sz)
	180	break;
	181	}
	182	cond_resched();
	183	}
	184
	185	*biop = bio;
	186	return 0;
	187	}
	188
3f14d792	189	/**
e73c23ff	190	* __blkdev_issue_zeroout - generate number of zero filed write bios
3f14d792 DM	191	* @bdev: blockdev to issue
	192	* @sector: start sector
	193	* @nr_sects: number of sectors to write
	194	* @gfp_mask: memory allocation flags (for bio_alloc)
e73c23ff	195	* @biop: pointer to anchor bio
ee472d83	196	* @flags: controls detailed behavior
3f14d792 DM	197	*
3f14d792 DM	198	* Description:
ee472d83 CH	199	* Zero-fill a block range, either using hardware offload or by explicitly
	200	* writing zeroes to the device.
	201	*
	202	* If a device is using logical block provisioning, the underlying space will
	203	* not be released if %flags contains BLKDEV_ZERO_NOUNMAP.
cb365b96 CH	204	*
	205	* If %flags contains BLKDEV_ZERO_NOFALLBACK, the function will return
	206	* -EOPNOTSUPP if no explicit hardware offload for zeroing is provided.
3f14d792	207	*/
e73c23ff CK	208	int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
e73c23ff CK	209	sector_t nr_sects, gfp_t gfp_mask, struct bio **biop,
ee472d83	210	unsigned flags)
3f14d792	211	{
18edc8ea	212	int ret;
28b2be20 DW	213	sector_t bs_mask;
	214
	215	bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
	216	if ((sector \| nr_sects) & bs_mask)
	217	return -EINVAL;
3f14d792	218
a6f0788e	219	ret = __blkdev_issue_write_zeroes(bdev, sector, nr_sects, gfp_mask,
d928be9f	220	biop, flags);
cb365b96	221	if (ret != -EOPNOTSUPP \|\| (flags & BLKDEV_ZERO_NOFALLBACK))
425a4dba	222	return ret;
3f14d792	223
425a4dba ID	224	return __blkdev_issue_zero_pages(bdev, sector, nr_sects, gfp_mask,
425a4dba ID	225	biop);
3f14d792	226	}
e73c23ff	227	EXPORT_SYMBOL(__blkdev_issue_zeroout);
579e8f3c MP	228
	229	/**
	230	* blkdev_issue_zeroout - zero-fill a block range
	231	* @bdev: blockdev to write
	232	* @sector: start sector
	233	* @nr_sects: number of sectors to write
	234	* @gfp_mask: memory allocation flags (for bio_alloc)
ee472d83	235	* @flags: controls detailed behavior
579e8f3c MP	236	*
579e8f3c MP	237	* Description:
ee472d83 CH	238	* Zero-fill a block range, either using hardware offload or by explicitly
	239	* writing zeroes to the device. See __blkdev_issue_zeroout() for the
	240	* valid values for %flags.
579e8f3c	241	*/
579e8f3c	242	int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
ee472d83	243	sector_t nr_sects, gfp_t gfp_mask, unsigned flags)
579e8f3c	244	{
d5ce4c31 ID	245	int ret = 0;
	246	sector_t bs_mask;
	247	struct bio *bio;
e73c23ff	248	struct blk_plug plug;
d5ce4c31	249	bool try_write_zeroes = !!bdev_write_zeroes_sectors(bdev);
d93ba7a5	250
d5ce4c31 ID	251	bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
	252	if ((sector \| nr_sects) & bs_mask)
	253	return -EINVAL;
	254
	255	retry:
	256	bio = NULL;
e73c23ff	257	blk_start_plug(&plug);
d5ce4c31 ID	258	if (try_write_zeroes) {
	259	ret = __blkdev_issue_write_zeroes(bdev, sector, nr_sects,
	260	gfp_mask, &bio, flags);
	261	} else if (!(flags & BLKDEV_ZERO_NOFALLBACK)) {
	262	ret = __blkdev_issue_zero_pages(bdev, sector, nr_sects,
	263	gfp_mask, &bio);
	264	} else {
	265	/* No zeroing offload support */
	266	ret = -EOPNOTSUPP;
	267	}
e73c23ff CK	268	if (ret == 0 && bio) {
	269	ret = submit_bio_wait(bio);
	270	bio_put(bio);
	271	}
	272	blk_finish_plug(&plug);
bf5e3a30	273	if (ret && try_write_zeroes) {
d5ce4c31 ID	274	if (!(flags & BLKDEV_ZERO_NOFALLBACK)) {
	275	try_write_zeroes = false;
	276	goto retry;
	277	}
	278	if (!bdev_write_zeroes_sectors(bdev)) {
	279	/*
	280	* Zeroing offload support was indicated, but the
	281	* device reported ILLEGAL REQUEST (for some devices
	282	* there is no non-destructive way to verify whether
	283	* WRITE ZEROES is actually supported).
	284	*/
	285	ret = -EOPNOTSUPP;
	286	}
	287	}
579e8f3c	288
e73c23ff	289	return ret;
579e8f3c	290	}
3f14d792	291	EXPORT_SYMBOL(blkdev_issue_zeroout);
44abff2c CH	292
	293	int blkdev_issue_secure_erase(struct block_device *bdev, sector_t sector,
	294	sector_t nr_sects, gfp_t gfp)
	295	{
	296	sector_t bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
	297	unsigned int max_sectors = bdev_max_secure_erase_sectors(bdev);
	298	struct bio *bio = NULL;
	299	struct blk_plug plug;
	300	int ret = 0;
	301
c4fa3684 MP	302	/* make sure that "len << SECTOR_SHIFT" doesn't overflow */
	303	if (max_sectors > UINT_MAX >> SECTOR_SHIFT)
	304	max_sectors = UINT_MAX >> SECTOR_SHIFT;
	305	max_sectors &= ~bs_mask;
	306
44abff2c CH	307	if (max_sectors == 0)
	308	return -EOPNOTSUPP;
	309	if ((sector \| nr_sects) & bs_mask)
	310	return -EINVAL;
	311	if (bdev_read_only(bdev))
	312	return -EPERM;
	313
	314	blk_start_plug(&plug);
5affe497	315	while (nr_sects) {
44abff2c CH	316	unsigned int len = min_t(sector_t, nr_sects, max_sectors);
	317
	318	bio = blk_next_bio(bio, bdev, 0, REQ_OP_SECURE_ERASE, gfp);
	319	bio->bi_iter.bi_sector = sector;
c4fa3684	320	bio->bi_iter.bi_size = len << SECTOR_SHIFT;
44abff2c	321
c4fa3684 MP	322	sector += len;
c4fa3684 MP	323	nr_sects -= len;
44abff2c CH	324	cond_resched();
44abff2c CH	325	}
5affe497 KB	326	if (bio) {
	327	ret = submit_bio_wait(bio);
	328	bio_put(bio);
	329	}
44abff2c CH	330	blk_finish_plug(&plug);
	331
	332	return ret;
	333	}
	334	EXPORT_SYMBOL(blkdev_issue_secure_erase);