Commit | Line | Data |
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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 | ||
4e49ea4a | 13 | static struct bio *next_bio(struct bio *bio, unsigned int nr_pages, |
9082e87b | 14 | gfp_t gfp) |
f31e7e40 | 15 | { |
9082e87b CH |
16 | struct bio *new = bio_alloc(gfp, nr_pages); |
17 | ||
18 | if (bio) { | |
19 | bio_chain(bio, new); | |
4e49ea4a | 20 | submit_bio(bio); |
9082e87b | 21 | } |
5dba3089 | 22 | |
9082e87b | 23 | return new; |
f31e7e40 DM |
24 | } |
25 | ||
38f25255 | 26 | int __blkdev_issue_discard(struct block_device *bdev, sector_t sector, |
288dab8a | 27 | sector_t nr_sects, gfp_t gfp_mask, int flags, |
469e3216 | 28 | struct bio **biop) |
f31e7e40 | 29 | { |
f31e7e40 | 30 | struct request_queue *q = bdev_get_queue(bdev); |
38f25255 | 31 | struct bio *bio = *biop; |
a22c4d7e | 32 | unsigned int granularity; |
ef295ecf | 33 | unsigned int op; |
a22c4d7e | 34 | int alignment; |
28b2be20 | 35 | sector_t bs_mask; |
f31e7e40 DM |
36 | |
37 | if (!q) | |
38 | return -ENXIO; | |
288dab8a | 39 | |
a13553c7 ID |
40 | if (bdev_read_only(bdev)) |
41 | return -EPERM; | |
42 | ||
288dab8a CH |
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 | } | |
f31e7e40 | 52 | |
28b2be20 DW |
53 | bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1; |
54 | if ((sector | nr_sects) & bs_mask) | |
55 | return -EINVAL; | |
56 | ||
a22c4d7e ML |
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 | ||
5dba3089 | 61 | while (nr_sects) { |
c6e66634 | 62 | unsigned int req_sects; |
a22c4d7e | 63 | sector_t end_sect, tmp; |
c6e66634 | 64 | |
a22c4d7e ML |
65 | /* Make sure bi_size doesn't overflow */ |
66 | req_sects = min_t(sector_t, nr_sects, UINT_MAX >> 9); | |
67 | ||
9082e87b | 68 | /** |
a22c4d7e ML |
69 | * If splitting a request, and the next starting sector would be |
70 | * misaligned, stop the discard at the previous aligned sector. | |
71 | */ | |
c6e66634 | 72 | end_sect = sector + req_sects; |
a22c4d7e ML |
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 | } | |
c6e66634 | 81 | |
f9d03f96 | 82 | bio = next_bio(bio, 0, gfp_mask); |
4f024f37 | 83 | bio->bi_iter.bi_sector = sector; |
74d46992 | 84 | bio_set_dev(bio, bdev); |
288dab8a | 85 | bio_set_op_attrs(bio, op, 0); |
f31e7e40 | 86 | |
4f024f37 | 87 | bio->bi_iter.bi_size = req_sects << 9; |
c6e66634 PB |
88 | nr_sects -= req_sects; |
89 | sector = end_sect; | |
f31e7e40 | 90 | |
c8123f8c JA |
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(); | |
5dba3089 | 98 | } |
38f25255 CH |
99 | |
100 | *biop = bio; | |
101 | return 0; | |
102 | } | |
103 | EXPORT_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) | |
e554911c | 111 | * @flags: BLKDEV_DISCARD_* flags to control behaviour |
38f25255 CH |
112 | * |
113 | * Description: | |
114 | * Issue a discard request for the sectors in question. | |
115 | */ | |
116 | int blkdev_issue_discard(struct block_device *bdev, sector_t sector, | |
117 | sector_t nr_sects, gfp_t gfp_mask, unsigned long flags) | |
118 | { | |
38f25255 CH |
119 | struct bio *bio = NULL; |
120 | struct blk_plug plug; | |
121 | int ret; | |
122 | ||
38f25255 | 123 | blk_start_plug(&plug); |
288dab8a | 124 | ret = __blkdev_issue_discard(bdev, sector, nr_sects, gfp_mask, flags, |
38f25255 | 125 | &bio); |
bbd848e0 | 126 | if (!ret && bio) { |
4e49ea4a | 127 | ret = submit_bio_wait(bio); |
48920ff2 | 128 | if (ret == -EOPNOTSUPP) |
bbd848e0 | 129 | ret = 0; |
05bd92dd | 130 | bio_put(bio); |
bbd848e0 | 131 | } |
0cfbcafc | 132 | blk_finish_plug(&plug); |
f31e7e40 | 133 | |
bbd848e0 | 134 | return ret; |
f31e7e40 DM |
135 | } |
136 | EXPORT_SYMBOL(blkdev_issue_discard); | |
3f14d792 | 137 | |
4363ac7c | 138 | /** |
e73c23ff | 139 | * __blkdev_issue_write_same - generate number of bios with same page |
4363ac7c MP |
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 | |
e73c23ff | 145 | * @biop: pointer to anchor bio |
4363ac7c MP |
146 | * |
147 | * Description: | |
e73c23ff | 148 | * Generate and issue number of bios(REQ_OP_WRITE_SAME) with same page. |
4363ac7c | 149 | */ |
e73c23ff CK |
150 | static 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) | |
4363ac7c | 153 | { |
4363ac7c MP |
154 | struct request_queue *q = bdev_get_queue(bdev); |
155 | unsigned int max_write_same_sectors; | |
e73c23ff | 156 | struct bio *bio = *biop; |
28b2be20 | 157 | sector_t bs_mask; |
4363ac7c MP |
158 | |
159 | if (!q) | |
160 | return -ENXIO; | |
161 | ||
a13553c7 ID |
162 | if (bdev_read_only(bdev)) |
163 | return -EPERM; | |
164 | ||
28b2be20 DW |
165 | bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1; |
166 | if ((sector | nr_sects) & bs_mask) | |
167 | return -EINVAL; | |
168 | ||
e73c23ff CK |
169 | if (!bdev_write_same(bdev)) |
170 | return -EOPNOTSUPP; | |
171 | ||
b49a0871 ML |
172 | /* Ensure that max_write_same_sectors doesn't overflow bi_size */ |
173 | max_write_same_sectors = UINT_MAX >> 9; | |
4363ac7c | 174 | |
4363ac7c | 175 | while (nr_sects) { |
4e49ea4a | 176 | bio = next_bio(bio, 1, gfp_mask); |
4f024f37 | 177 | bio->bi_iter.bi_sector = sector; |
74d46992 | 178 | bio_set_dev(bio, bdev); |
4363ac7c MP |
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); | |
95fe6c1a | 183 | bio_set_op_attrs(bio, REQ_OP_WRITE_SAME, 0); |
4363ac7c MP |
184 | |
185 | if (nr_sects > max_write_same_sectors) { | |
4f024f37 | 186 | bio->bi_iter.bi_size = max_write_same_sectors << 9; |
4363ac7c MP |
187 | nr_sects -= max_write_same_sectors; |
188 | sector += max_write_same_sectors; | |
189 | } else { | |
4f024f37 | 190 | bio->bi_iter.bi_size = nr_sects << 9; |
4363ac7c MP |
191 | nr_sects = 0; |
192 | } | |
e73c23ff | 193 | cond_resched(); |
4363ac7c MP |
194 | } |
195 | ||
e73c23ff CK |
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 | */ | |
211 | int 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) { | |
4e49ea4a | 223 | ret = submit_bio_wait(bio); |
05bd92dd ST |
224 | bio_put(bio); |
225 | } | |
e73c23ff | 226 | blk_finish_plug(&plug); |
3f40bf2c | 227 | return ret; |
4363ac7c MP |
228 | } |
229 | EXPORT_SYMBOL(blkdev_issue_write_same); | |
230 | ||
a6f0788e CK |
231 | static int __blkdev_issue_write_zeroes(struct block_device *bdev, |
232 | sector_t sector, sector_t nr_sects, gfp_t gfp_mask, | |
d928be9f | 233 | struct bio **biop, unsigned flags) |
a6f0788e CK |
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 | ||
a13553c7 ID |
242 | if (bdev_read_only(bdev)) |
243 | return -EPERM; | |
244 | ||
a6f0788e CK |
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; | |
74d46992 | 254 | bio_set_dev(bio, bdev); |
d928be9f CH |
255 | bio->bi_opf = REQ_OP_WRITE_ZEROES; |
256 | if (flags & BLKDEV_ZERO_NOUNMAP) | |
257 | bio->bi_opf |= REQ_NOUNMAP; | |
a6f0788e CK |
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 | ||
615d22a5 DLM |
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 | */ | |
280 | static unsigned int __blkdev_sectors_to_bio_pages(sector_t nr_sects) | |
281 | { | |
09c2c359 | 282 | sector_t pages = DIV_ROUND_UP_SECTOR_T(nr_sects, PAGE_SIZE / 512); |
615d22a5 | 283 | |
09c2c359 | 284 | return min(pages, (sector_t)BIO_MAX_PAGES); |
615d22a5 DLM |
285 | } |
286 | ||
425a4dba ID |
287 | static 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 | ||
a13553c7 ID |
299 | if (bdev_read_only(bdev)) |
300 | return -EPERM; | |
301 | ||
425a4dba ID |
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 | ||
3f14d792 | 324 | /** |
e73c23ff | 325 | * __blkdev_issue_zeroout - generate number of zero filed write bios |
3f14d792 DM |
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) | |
e73c23ff | 330 | * @biop: pointer to anchor bio |
ee472d83 | 331 | * @flags: controls detailed behavior |
3f14d792 DM |
332 | * |
333 | * Description: | |
ee472d83 CH |
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. | |
cb365b96 CH |
339 | * |
340 | * If %flags contains BLKDEV_ZERO_NOFALLBACK, the function will return | |
341 | * -EOPNOTSUPP if no explicit hardware offload for zeroing is provided. | |
3f14d792 | 342 | */ |
e73c23ff CK |
343 | int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, |
344 | sector_t nr_sects, gfp_t gfp_mask, struct bio **biop, | |
ee472d83 | 345 | unsigned flags) |
3f14d792 | 346 | { |
18edc8ea | 347 | int ret; |
28b2be20 DW |
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; | |
3f14d792 | 353 | |
a6f0788e | 354 | ret = __blkdev_issue_write_zeroes(bdev, sector, nr_sects, gfp_mask, |
d928be9f | 355 | biop, flags); |
cb365b96 | 356 | if (ret != -EOPNOTSUPP || (flags & BLKDEV_ZERO_NOFALLBACK)) |
425a4dba | 357 | return ret; |
3f14d792 | 358 | |
425a4dba ID |
359 | return __blkdev_issue_zero_pages(bdev, sector, nr_sects, gfp_mask, |
360 | biop); | |
3f14d792 | 361 | } |
e73c23ff | 362 | EXPORT_SYMBOL(__blkdev_issue_zeroout); |
579e8f3c MP |
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) | |
ee472d83 | 370 | * @flags: controls detailed behavior |
579e8f3c MP |
371 | * |
372 | * Description: | |
ee472d83 CH |
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. | |
579e8f3c | 376 | */ |
579e8f3c | 377 | int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, |
ee472d83 | 378 | sector_t nr_sects, gfp_t gfp_mask, unsigned flags) |
579e8f3c | 379 | { |
d5ce4c31 ID |
380 | int ret = 0; |
381 | sector_t bs_mask; | |
382 | struct bio *bio; | |
e73c23ff | 383 | struct blk_plug plug; |
d5ce4c31 | 384 | bool try_write_zeroes = !!bdev_write_zeroes_sectors(bdev); |
d93ba7a5 | 385 | |
d5ce4c31 ID |
386 | bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1; |
387 | if ((sector | nr_sects) & bs_mask) | |
388 | return -EINVAL; | |
389 | ||
390 | retry: | |
391 | bio = NULL; | |
e73c23ff | 392 | blk_start_plug(&plug); |
d5ce4c31 ID |
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 | } | |
e73c23ff CK |
403 | if (ret == 0 && bio) { |
404 | ret = submit_bio_wait(bio); | |
405 | bio_put(bio); | |
406 | } | |
407 | blk_finish_plug(&plug); | |
d5ce4c31 ID |
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 | } | |
579e8f3c | 423 | |
e73c23ff | 424 | return ret; |
579e8f3c | 425 | } |
3f14d792 | 426 | EXPORT_SYMBOL(blkdev_issue_zeroout); |