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1// SPDX-License-Identifier: GPL-2.0
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
13static struct bio *next_bio(struct bio *bio, unsigned int nr_pages,
14 gfp_t gfp)
15{
16 struct bio *new = bio_alloc(gfp, nr_pages);
17
18 if (bio) {
19 bio_chain(bio, new);
20 submit_bio(bio);
21 }
22
23 return new;
24}
25
26int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
27 sector_t nr_sects, gfp_t gfp_mask, int flags,
28 struct bio **biop)
29{
30 struct request_queue *q = bdev_get_queue(bdev);
31 struct bio *bio = *biop;
32 unsigned int granularity;
33 unsigned int op;
34 int alignment;
35 sector_t bs_mask;
36
37 if (!q)
38 return -ENXIO;
39
40 if (bdev_read_only(bdev))
41 return -EPERM;
42
43 if (flags & BLKDEV_DISCARD_SECURE) {
44 if (!blk_queue_secure_erase(q))
45 return -EOPNOTSUPP;
46 op = REQ_OP_SECURE_ERASE;
47 } else {
48 if (!blk_queue_discard(q))
49 return -EOPNOTSUPP;
50 op = REQ_OP_DISCARD;
51 }
52
53 bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
54 if ((sector | nr_sects) & bs_mask)
55 return -EINVAL;
56
57 /* Zero-sector (unknown) and one-sector granularities are the same. */
58 granularity = max(q->limits.discard_granularity >> 9, 1U);
59 alignment = (bdev_discard_alignment(bdev) >> 9) % granularity;
60
61 while (nr_sects) {
62 unsigned int req_sects;
63 sector_t end_sect, tmp;
64
65 /* Make sure bi_size doesn't overflow */
66 req_sects = min_t(sector_t, nr_sects, UINT_MAX >> 9);
67
68 /**
69 * If splitting a request, and the next starting sector would be
70 * misaligned, stop the discard at the previous aligned sector.
71 */
72 end_sect = sector + req_sects;
73 tmp = end_sect;
74 if (req_sects < nr_sects &&
75 sector_div(tmp, granularity) != alignment) {
76 end_sect = end_sect - alignment;
77 sector_div(end_sect, granularity);
78 end_sect = end_sect * granularity + alignment;
79 req_sects = end_sect - sector;
80 }
81
82 bio = next_bio(bio, 0, gfp_mask);
83 bio->bi_iter.bi_sector = sector;
84 bio_set_dev(bio, bdev);
85 bio_set_op_attrs(bio, op, 0);
86
87 bio->bi_iter.bi_size = req_sects << 9;
88 nr_sects -= req_sects;
89 sector = end_sect;
90
91 /*
92 * We can loop for a long time in here, if someone does
93 * full device discards (like mkfs). Be nice and allow
94 * us to schedule out to avoid softlocking if preempt
95 * is disabled.
96 */
97 cond_resched();
98 }
99
100 *biop = bio;
101 return 0;
102}
103EXPORT_SYMBOL(__blkdev_issue_discard);
104
105/**
106 * blkdev_issue_discard - queue a discard
107 * @bdev: blockdev to issue discard for
108 * @sector: start sector
109 * @nr_sects: number of sectors to discard
110 * @gfp_mask: memory allocation flags (for bio_alloc)
111 * @flags: BLKDEV_DISCARD_* flags to control behaviour
112 *
113 * Description:
114 * Issue a discard request for the sectors in question.
115 */
116int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
117 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags)
118{
119 struct bio *bio = NULL;
120 struct blk_plug plug;
121 int ret;
122
123 blk_start_plug(&plug);
124 ret = __blkdev_issue_discard(bdev, sector, nr_sects, gfp_mask, flags,
125 &bio);
126 if (!ret && bio) {
127 ret = submit_bio_wait(bio);
128 if (ret == -EOPNOTSUPP)
129 ret = 0;
130 bio_put(bio);
131 }
132 blk_finish_plug(&plug);
133
134 return ret;
135}
136EXPORT_SYMBOL(blkdev_issue_discard);
137
138/**
139 * __blkdev_issue_write_same - generate number of bios with same page
140 * @bdev: target blockdev
141 * @sector: start sector
142 * @nr_sects: number of sectors to write
143 * @gfp_mask: memory allocation flags (for bio_alloc)
144 * @page: page containing data to write
145 * @biop: pointer to anchor bio
146 *
147 * Description:
148 * Generate and issue number of bios(REQ_OP_WRITE_SAME) with same page.
149 */
150static int __blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
151 sector_t nr_sects, gfp_t gfp_mask, struct page *page,
152 struct bio **biop)
153{
154 struct request_queue *q = bdev_get_queue(bdev);
155 unsigned int max_write_same_sectors;
156 struct bio *bio = *biop;
157 sector_t bs_mask;
158
159 if (!q)
160 return -ENXIO;
161
162 if (bdev_read_only(bdev))
163 return -EPERM;
164
165 bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
166 if ((sector | nr_sects) & bs_mask)
167 return -EINVAL;
168
169 if (!bdev_write_same(bdev))
170 return -EOPNOTSUPP;
171
172 /* Ensure that max_write_same_sectors doesn't overflow bi_size */
173 max_write_same_sectors = UINT_MAX >> 9;
174
175 while (nr_sects) {
176 bio = next_bio(bio, 1, gfp_mask);
177 bio->bi_iter.bi_sector = sector;
178 bio_set_dev(bio, bdev);
179 bio->bi_vcnt = 1;
180 bio->bi_io_vec->bv_page = page;
181 bio->bi_io_vec->bv_offset = 0;
182 bio->bi_io_vec->bv_len = bdev_logical_block_size(bdev);
183 bio_set_op_attrs(bio, REQ_OP_WRITE_SAME, 0);
184
185 if (nr_sects > max_write_same_sectors) {
186 bio->bi_iter.bi_size = max_write_same_sectors << 9;
187 nr_sects -= max_write_same_sectors;
188 sector += max_write_same_sectors;
189 } else {
190 bio->bi_iter.bi_size = nr_sects << 9;
191 nr_sects = 0;
192 }
193 cond_resched();
194 }
195
196 *biop = bio;
197 return 0;
198}
199
200/**
201 * blkdev_issue_write_same - queue a write same operation
202 * @bdev: target blockdev
203 * @sector: start sector
204 * @nr_sects: number of sectors to write
205 * @gfp_mask: memory allocation flags (for bio_alloc)
206 * @page: page containing data
207 *
208 * Description:
209 * Issue a write same request for the sectors in question.
210 */
211int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
212 sector_t nr_sects, gfp_t gfp_mask,
213 struct page *page)
214{
215 struct bio *bio = NULL;
216 struct blk_plug plug;
217 int ret;
218
219 blk_start_plug(&plug);
220 ret = __blkdev_issue_write_same(bdev, sector, nr_sects, gfp_mask, page,
221 &bio);
222 if (ret == 0 && bio) {
223 ret = submit_bio_wait(bio);
224 bio_put(bio);
225 }
226 blk_finish_plug(&plug);
227 return ret;
228}
229EXPORT_SYMBOL(blkdev_issue_write_same);
230
231static int __blkdev_issue_write_zeroes(struct block_device *bdev,
232 sector_t sector, sector_t nr_sects, gfp_t gfp_mask,
233 struct bio **biop, unsigned flags)
234{
235 struct bio *bio = *biop;
236 unsigned int max_write_zeroes_sectors;
237 struct request_queue *q = bdev_get_queue(bdev);
238
239 if (!q)
240 return -ENXIO;
241
242 if (bdev_read_only(bdev))
243 return -EPERM;
244
245 /* Ensure that max_write_zeroes_sectors doesn't overflow bi_size */
246 max_write_zeroes_sectors = bdev_write_zeroes_sectors(bdev);
247
248 if (max_write_zeroes_sectors == 0)
249 return -EOPNOTSUPP;
250
251 while (nr_sects) {
252 bio = next_bio(bio, 0, gfp_mask);
253 bio->bi_iter.bi_sector = sector;
254 bio_set_dev(bio, bdev);
255 bio->bi_opf = REQ_OP_WRITE_ZEROES;
256 if (flags & BLKDEV_ZERO_NOUNMAP)
257 bio->bi_opf |= REQ_NOUNMAP;
258
259 if (nr_sects > max_write_zeroes_sectors) {
260 bio->bi_iter.bi_size = max_write_zeroes_sectors << 9;
261 nr_sects -= max_write_zeroes_sectors;
262 sector += max_write_zeroes_sectors;
263 } else {
264 bio->bi_iter.bi_size = nr_sects << 9;
265 nr_sects = 0;
266 }
267 cond_resched();
268 }
269
270 *biop = bio;
271 return 0;
272}
273
274/*
275 * Convert a number of 512B sectors to a number of pages.
276 * The result is limited to a number of pages that can fit into a BIO.
277 * Also make sure that the result is always at least 1 (page) for the cases
278 * where nr_sects is lower than the number of sectors in a page.
279 */
280static unsigned int __blkdev_sectors_to_bio_pages(sector_t nr_sects)
281{
282 sector_t pages = DIV_ROUND_UP_SECTOR_T(nr_sects, PAGE_SIZE / 512);
283
284 return min(pages, (sector_t)BIO_MAX_PAGES);
285}
286
287static int __blkdev_issue_zero_pages(struct block_device *bdev,
288 sector_t sector, sector_t nr_sects, gfp_t gfp_mask,
289 struct bio **biop)
290{
291 struct request_queue *q = bdev_get_queue(bdev);
292 struct bio *bio = *biop;
293 int bi_size = 0;
294 unsigned int sz;
295
296 if (!q)
297 return -ENXIO;
298
299 if (bdev_read_only(bdev))
300 return -EPERM;
301
302 while (nr_sects != 0) {
303 bio = next_bio(bio, __blkdev_sectors_to_bio_pages(nr_sects),
304 gfp_mask);
305 bio->bi_iter.bi_sector = sector;
306 bio_set_dev(bio, bdev);
307 bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
308
309 while (nr_sects != 0) {
310 sz = min((sector_t) PAGE_SIZE, nr_sects << 9);
311 bi_size = bio_add_page(bio, ZERO_PAGE(0), sz, 0);
312 nr_sects -= bi_size >> 9;
313 sector += bi_size >> 9;
314 if (bi_size < sz)
315 break;
316 }
317 cond_resched();
318 }
319
320 *biop = bio;
321 return 0;
322}
323
324/**
325 * __blkdev_issue_zeroout - generate number of zero filed write bios
326 * @bdev: blockdev to issue
327 * @sector: start sector
328 * @nr_sects: number of sectors to write
329 * @gfp_mask: memory allocation flags (for bio_alloc)
330 * @biop: pointer to anchor bio
331 * @flags: controls detailed behavior
332 *
333 * Description:
334 * Zero-fill a block range, either using hardware offload or by explicitly
335 * writing zeroes to the device.
336 *
337 * If a device is using logical block provisioning, the underlying space will
338 * not be released if %flags contains BLKDEV_ZERO_NOUNMAP.
339 *
340 * If %flags contains BLKDEV_ZERO_NOFALLBACK, the function will return
341 * -EOPNOTSUPP if no explicit hardware offload for zeroing is provided.
342 */
343int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
344 sector_t nr_sects, gfp_t gfp_mask, struct bio **biop,
345 unsigned flags)
346{
347 int ret;
348 sector_t bs_mask;
349
350 bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
351 if ((sector | nr_sects) & bs_mask)
352 return -EINVAL;
353
354 ret = __blkdev_issue_write_zeroes(bdev, sector, nr_sects, gfp_mask,
355 biop, flags);
356 if (ret != -EOPNOTSUPP || (flags & BLKDEV_ZERO_NOFALLBACK))
357 return ret;
358
359 return __blkdev_issue_zero_pages(bdev, sector, nr_sects, gfp_mask,
360 biop);
361}
362EXPORT_SYMBOL(__blkdev_issue_zeroout);
363
364/**
365 * blkdev_issue_zeroout - zero-fill a block range
366 * @bdev: blockdev to write
367 * @sector: start sector
368 * @nr_sects: number of sectors to write
369 * @gfp_mask: memory allocation flags (for bio_alloc)
370 * @flags: controls detailed behavior
371 *
372 * Description:
373 * Zero-fill a block range, either using hardware offload or by explicitly
374 * writing zeroes to the device. See __blkdev_issue_zeroout() for the
375 * valid values for %flags.
376 */
377int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
378 sector_t nr_sects, gfp_t gfp_mask, unsigned flags)
379{
380 int ret = 0;
381 sector_t bs_mask;
382 struct bio *bio;
383 struct blk_plug plug;
384 bool try_write_zeroes = !!bdev_write_zeroes_sectors(bdev);
385
386 bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
387 if ((sector | nr_sects) & bs_mask)
388 return -EINVAL;
389
390retry:
391 bio = NULL;
392 blk_start_plug(&plug);
393 if (try_write_zeroes) {
394 ret = __blkdev_issue_write_zeroes(bdev, sector, nr_sects,
395 gfp_mask, &bio, flags);
396 } else if (!(flags & BLKDEV_ZERO_NOFALLBACK)) {
397 ret = __blkdev_issue_zero_pages(bdev, sector, nr_sects,
398 gfp_mask, &bio);
399 } else {
400 /* No zeroing offload support */
401 ret = -EOPNOTSUPP;
402 }
403 if (ret == 0 && bio) {
404 ret = submit_bio_wait(bio);
405 bio_put(bio);
406 }
407 blk_finish_plug(&plug);
408 if (ret && try_write_zeroes) {
409 if (!(flags & BLKDEV_ZERO_NOFALLBACK)) {
410 try_write_zeroes = false;
411 goto retry;
412 }
413 if (!bdev_write_zeroes_sectors(bdev)) {
414 /*
415 * Zeroing offload support was indicated, but the
416 * device reported ILLEGAL REQUEST (for some devices
417 * there is no non-destructive way to verify whether
418 * WRITE ZEROES is actually supported).
419 */
420 ret = -EOPNOTSUPP;
421 }
422 }
423
424 return ret;
425}
426EXPORT_SYMBOL(blkdev_issue_zeroout);
1// SPDX-License-Identifier: GPL-2.0
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
13static sector_t bio_discard_limit(struct block_device *bdev, sector_t sector)
14{
15 unsigned int discard_granularity = bdev_discard_granularity(bdev);
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
38int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
39 sector_t nr_sects, gfp_t gfp_mask, struct bio **biop)
40{
41 struct bio *bio = *biop;
42 sector_t bs_mask;
43
44 if (bdev_read_only(bdev))
45 return -EPERM;
46 if (!bdev_max_discard_sectors(bdev))
47 return -EOPNOTSUPP;
48
49 /* In case the discard granularity isn't set by buggy device driver */
50 if (WARN_ON_ONCE(!bdev_discard_granularity(bdev))) {
51 pr_err_ratelimited("%pg: Error: discard_granularity is 0.\n",
52 bdev);
53 return -EOPNOTSUPP;
54 }
55
56 bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
57 if ((sector | nr_sects) & bs_mask)
58 return -EINVAL;
59
60 if (!nr_sects)
61 return -EINVAL;
62
63 while (nr_sects) {
64 sector_t req_sects =
65 min(nr_sects, bio_discard_limit(bdev, sector));
66
67 bio = blk_next_bio(bio, bdev, 0, REQ_OP_DISCARD, gfp_mask);
68 bio->bi_iter.bi_sector = sector;
69 bio->bi_iter.bi_size = req_sects << 9;
70 sector += req_sects;
71 nr_sects -= req_sects;
72
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();
80 }
81
82 *biop = bio;
83 return 0;
84}
85EXPORT_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)
93 *
94 * Description:
95 * Issue a discard request for the sectors in question.
96 */
97int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
98 sector_t nr_sects, gfp_t gfp_mask)
99{
100 struct bio *bio = NULL;
101 struct blk_plug plug;
102 int ret;
103
104 blk_start_plug(&plug);
105 ret = __blkdev_issue_discard(bdev, sector, nr_sects, gfp_mask, &bio);
106 if (!ret && bio) {
107 ret = submit_bio_wait(bio);
108 if (ret == -EOPNOTSUPP)
109 ret = 0;
110 bio_put(bio);
111 }
112 blk_finish_plug(&plug);
113
114 return ret;
115}
116EXPORT_SYMBOL(blkdev_issue_discard);
117
118static int __blkdev_issue_write_zeroes(struct block_device *bdev,
119 sector_t sector, sector_t nr_sects, gfp_t gfp_mask,
120 struct bio **biop, unsigned flags)
121{
122 struct bio *bio = *biop;
123 unsigned int max_sectors;
124
125 if (bdev_read_only(bdev))
126 return -EPERM;
127
128 /* Ensure that max_sectors doesn't overflow bi_size */
129 max_sectors = bdev_write_zeroes_sectors(bdev);
130
131 if (max_sectors == 0)
132 return -EOPNOTSUPP;
133
134 while (nr_sects) {
135 unsigned int len = min_t(sector_t, nr_sects, max_sectors);
136
137 bio = blk_next_bio(bio, bdev, 0, REQ_OP_WRITE_ZEROES, gfp_mask);
138 bio->bi_iter.bi_sector = sector;
139 if (flags & BLKDEV_ZERO_NOUNMAP)
140 bio->bi_opf |= REQ_NOUNMAP;
141
142 bio->bi_iter.bi_size = len << SECTOR_SHIFT;
143 nr_sects -= len;
144 sector += len;
145 cond_resched();
146 }
147
148 *biop = bio;
149 return 0;
150}
151
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 */
158static unsigned int __blkdev_sectors_to_bio_pages(sector_t nr_sects)
159{
160 sector_t pages = DIV_ROUND_UP_SECTOR_T(nr_sects, PAGE_SIZE / 512);
161
162 return min(pages, (sector_t)BIO_MAX_VECS);
163}
164
165static 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{
169 struct bio *bio = *biop;
170 int bi_size = 0;
171 unsigned int sz;
172
173 if (bdev_read_only(bdev))
174 return -EPERM;
175
176 while (nr_sects != 0) {
177 bio = blk_next_bio(bio, bdev, __blkdev_sectors_to_bio_pages(nr_sects),
178 REQ_OP_WRITE, gfp_mask);
179 bio->bi_iter.bi_sector = sector;
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
196/**
197 * __blkdev_issue_zeroout - generate number of zero filed write bios
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)
202 * @biop: pointer to anchor bio
203 * @flags: controls detailed behavior
204 *
205 * Description:
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.
211 *
212 * If %flags contains BLKDEV_ZERO_NOFALLBACK, the function will return
213 * -EOPNOTSUPP if no explicit hardware offload for zeroing is provided.
214 */
215int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
216 sector_t nr_sects, gfp_t gfp_mask, struct bio **biop,
217 unsigned flags)
218{
219 int ret;
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;
225
226 ret = __blkdev_issue_write_zeroes(bdev, sector, nr_sects, gfp_mask,
227 biop, flags);
228 if (ret != -EOPNOTSUPP || (flags & BLKDEV_ZERO_NOFALLBACK))
229 return ret;
230
231 return __blkdev_issue_zero_pages(bdev, sector, nr_sects, gfp_mask,
232 biop);
233}
234EXPORT_SYMBOL(__blkdev_issue_zeroout);
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)
242 * @flags: controls detailed behavior
243 *
244 * Description:
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.
248 */
249int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
250 sector_t nr_sects, gfp_t gfp_mask, unsigned flags)
251{
252 int ret = 0;
253 sector_t bs_mask;
254 struct bio *bio;
255 struct blk_plug plug;
256 bool try_write_zeroes = !!bdev_write_zeroes_sectors(bdev);
257
258 bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
259 if ((sector | nr_sects) & bs_mask)
260 return -EINVAL;
261
262retry:
263 bio = NULL;
264 blk_start_plug(&plug);
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 }
275 if (ret == 0 && bio) {
276 ret = submit_bio_wait(bio);
277 bio_put(bio);
278 }
279 blk_finish_plug(&plug);
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 }
295
296 return ret;
297}
298EXPORT_SYMBOL(blkdev_issue_zeroout);
299
300int 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
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
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);
322 while (nr_sects) {
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;
327 bio->bi_iter.bi_size = len << SECTOR_SHIFT;
328
329 sector += len;
330 nr_sects -= len;
331 cond_resched();
332 }
333 if (bio) {
334 ret = submit_bio_wait(bio);
335 bio_put(bio);
336 }
337 blk_finish_plug(&plug);
338
339 return ret;
340}
341EXPORT_SYMBOL(blkdev_issue_secure_erase);