1 // SPDX-License-Identifier: GPL-2.0 1 // SPDX-License-Identifier: GPL-2.0
2 /* 2 /*
3 * Functions related to generic helpers functi 3 * Functions related to generic helpers functions
4 */ 4 */
5 #include <linux/kernel.h> 5 #include <linux/kernel.h>
6 #include <linux/module.h> 6 #include <linux/module.h>
7 #include <linux/bio.h> 7 #include <linux/bio.h>
8 #include <linux/blkdev.h> 8 #include <linux/blkdev.h>
9 #include <linux/scatterlist.h> 9 #include <linux/scatterlist.h>
10 10
11 #include "blk.h" 11 #include "blk.h"
12 12
13 static sector_t bio_discard_limit(struct block !! 13 static struct bio *next_bio(struct bio *bio, unsigned int nr_pages,
>> 14 gfp_t gfp)
14 { 15 {
15 unsigned int discard_granularity = bde !! 16 struct bio *new = bio_alloc(gfp, nr_pages);
16 sector_t granularity_aligned_sector; <<
17 17
18 if (bdev_is_partition(bdev)) !! 18 if (bio) {
19 sector += bdev->bd_start_sect; !! 19 bio_chain(bio, new);
20 !! 20 submit_bio(bio);
21 granularity_aligned_sector = !! 21 }
22 round_up(sector, discard_granu <<
23 22
24 /* !! 23 return new;
25 * Make sure subsequent bios start ali <<
26 * it needs to be split. <<
27 */ <<
28 if (granularity_aligned_sector != sect <<
29 return granularity_aligned_sec <<
30 <<
31 /* <<
32 * Align the bio size to the discard g <<
33 * at discard granularity boundaries e <<
34 */ <<
35 return round_down(UINT_MAX, discard_gr <<
36 } 24 }
37 25
38 struct bio *blk_alloc_discard_bio(struct block !! 26 int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
39 sector_t *sector, sector_t *nr !! 27 sector_t nr_sects, gfp_t gfp_mask, int flags,
>> 28 struct bio **biop)
40 { 29 {
41 sector_t bio_sects = min(*nr_sects, bi !! 30 struct request_queue *q = bdev_get_queue(bdev);
42 struct bio *bio; !! 31 struct bio *bio = *biop;
>> 32 unsigned int granularity;
>> 33 unsigned int op;
>> 34 int alignment;
>> 35 sector_t bs_mask;
43 36
44 if (!bio_sects) !! 37 if (!q)
45 return NULL; !! 38 return -ENXIO;
46 39
47 bio = bio_alloc(bdev, 0, REQ_OP_DISCAR !! 40 if (bdev_read_only(bdev))
48 if (!bio) !! 41 return -EPERM;
49 return NULL; <<
50 bio->bi_iter.bi_sector = *sector; <<
51 bio->bi_iter.bi_size = bio_sects << SE <<
52 *sector += bio_sects; <<
53 *nr_sects -= bio_sects; <<
54 /* <<
55 * We can loop for a long time in here <<
56 * discards (like mkfs). Be nice and <<
57 * softlocking if preempt is disabled. <<
58 */ <<
59 cond_resched(); <<
60 return bio; <<
61 } <<
62 42
63 int __blkdev_issue_discard(struct block_device !! 43 if (flags & BLKDEV_DISCARD_SECURE) {
64 sector_t nr_sects, gfp_t gfp_m !! 44 if (!blk_queue_secure_erase(q))
65 { !! 45 return -EOPNOTSUPP;
66 struct bio *bio; !! 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);
67 86
68 while ((bio = blk_alloc_discard_bio(bd !! 87 bio->bi_iter.bi_size = req_sects << 9;
69 gfp_mask))) !! 88 nr_sects -= req_sects;
70 *biop = bio_chain_and_submit(* !! 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;
71 return 0; 101 return 0;
72 } 102 }
73 EXPORT_SYMBOL(__blkdev_issue_discard); 103 EXPORT_SYMBOL(__blkdev_issue_discard);
74 104
75 /** 105 /**
76 * blkdev_issue_discard - queue a discard 106 * blkdev_issue_discard - queue a discard
77 * @bdev: blockdev to issue discard for 107 * @bdev: blockdev to issue discard for
78 * @sector: start sector 108 * @sector: start sector
79 * @nr_sects: number of sectors to discard 109 * @nr_sects: number of sectors to discard
80 * @gfp_mask: memory allocation flags (for b 110 * @gfp_mask: memory allocation flags (for bio_alloc)
>> 111 * @flags: BLKDEV_DISCARD_* flags to control behaviour
81 * 112 *
82 * Description: 113 * Description:
83 * Issue a discard request for the sectors 114 * Issue a discard request for the sectors in question.
84 */ 115 */
85 int blkdev_issue_discard(struct block_device * 116 int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
86 sector_t nr_sects, gfp_t gfp_m !! 117 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags)
87 { 118 {
88 struct bio *bio = NULL; 119 struct bio *bio = NULL;
89 struct blk_plug plug; 120 struct blk_plug plug;
90 int ret; 121 int ret;
91 122
92 blk_start_plug(&plug); 123 blk_start_plug(&plug);
93 ret = __blkdev_issue_discard(bdev, sec !! 124 ret = __blkdev_issue_discard(bdev, sector, nr_sects, gfp_mask, flags,
>> 125 &bio);
94 if (!ret && bio) { 126 if (!ret && bio) {
95 ret = submit_bio_wait(bio); 127 ret = submit_bio_wait(bio);
96 if (ret == -EOPNOTSUPP) 128 if (ret == -EOPNOTSUPP)
97 ret = 0; 129 ret = 0;
98 bio_put(bio); 130 bio_put(bio);
99 } 131 }
100 blk_finish_plug(&plug); 132 blk_finish_plug(&plug);
101 133
102 return ret; 134 return ret;
103 } 135 }
104 EXPORT_SYMBOL(blkdev_issue_discard); 136 EXPORT_SYMBOL(blkdev_issue_discard);
105 137
106 static sector_t bio_write_zeroes_limit(struct !! 138 /**
107 { !! 139 * __blkdev_issue_write_same - generate number of bios with same page
108 sector_t bs_mask = (bdev_logical_block !! 140 * @bdev: target blockdev
109 !! 141 * @sector: start sector
110 return min(bdev_write_zeroes_sectors(b !! 142 * @nr_sects: number of sectors to write
111 (UINT_MAX >> SECTOR_SHIFT) & ~ !! 143 * @gfp_mask: memory allocation flags (for bio_alloc)
112 } !! 144 * @page: page containing data to write
113 !! 145 * @biop: pointer to anchor bio
114 /* !! 146 *
115 * There is no reliable way for the SCSI subsy !! 147 * Description:
116 * device supports a WRITE SAME operation with !! 148 * Generate and issue number of bios(REQ_OP_WRITE_SAME) with same page.
117 * to media. As a result, write_zeroes is enab <<
118 * disabled if a zeroing operation subsequentl <<
119 * queue limit is likely to change at runtime. <<
120 */ 149 */
121 static void __blkdev_issue_write_zeroes(struct !! 150 static int __blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
122 sector_t sector, sector_t nr_s !! 151 sector_t nr_sects, gfp_t gfp_mask, struct page *page,
123 struct bio **biop, unsigned fl !! 152 struct bio **biop)
124 { !! 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;
125 158
126 while (nr_sects) { !! 159 if (!q)
127 unsigned int len = min(nr_sect !! 160 return -ENXIO;
128 struct bio *bio; <<
129 161
130 if ((flags & BLKDEV_ZERO_KILLA !! 162 if (bdev_read_only(bdev))
131 fatal_signal_pending(curre !! 163 return -EPERM;
132 break; <<
133 164
134 bio = bio_alloc(bdev, 0, REQ_O !! 165 bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
135 bio->bi_iter.bi_sector = secto !! 166 if ((sector | nr_sects) & bs_mask)
136 if (flags & BLKDEV_ZERO_NOUNMA !! 167 return -EINVAL;
137 bio->bi_opf |= REQ_NOU !! 168
>> 169 if (!bdev_write_same(bdev))
>> 170 return -EOPNOTSUPP;
138 171
139 bio->bi_iter.bi_size = len << !! 172 /* Ensure that max_write_same_sectors doesn't overflow bi_size */
140 *biop = bio_chain_and_submit(* !! 173 max_write_same_sectors = UINT_MAX >> 9;
141 174
142 nr_sects -= len; !! 175 while (nr_sects) {
143 sector += len; !! 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 }
144 cond_resched(); 193 cond_resched();
145 } 194 }
>> 195
>> 196 *biop = bio;
>> 197 return 0;
146 } 198 }
147 199
148 static int blkdev_issue_write_zeroes(struct bl !! 200 /**
149 sector_t nr_sects, gfp_t gfp, !! 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)
150 { 214 {
151 sector_t limit = bio_write_zeroes_limi <<
152 struct bio *bio = NULL; 215 struct bio *bio = NULL;
153 struct blk_plug plug; 216 struct blk_plug plug;
154 int ret = 0; !! 217 int ret;
155 218
156 blk_start_plug(&plug); 219 blk_start_plug(&plug);
157 __blkdev_issue_write_zeroes(bdev, sect !! 220 ret = __blkdev_issue_write_same(bdev, sector, nr_sects, gfp_mask, page,
158 flags, limit); !! 221 &bio);
159 if (bio) { !! 222 if (ret == 0 && bio) {
160 if ((flags & BLKDEV_ZERO_KILLA <<
161 fatal_signal_pending(curre <<
162 bio_await_chain(bio); <<
163 blk_finish_plug(&plug) <<
164 return -EINTR; <<
165 } <<
166 ret = submit_bio_wait(bio); 223 ret = submit_bio_wait(bio);
167 bio_put(bio); 224 bio_put(bio);
168 } 225 }
169 blk_finish_plug(&plug); 226 blk_finish_plug(&plug);
>> 227 return ret;
>> 228 }
>> 229 EXPORT_SYMBOL(blkdev_issue_write_same);
>> 230
>> 231 static 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);
170 247
171 /* !! 248 if (max_write_zeroes_sectors == 0)
172 * For some devices there is no non-de <<
173 * WRITE ZEROES is actually supported. <<
174 * on an I/O error, in which case we'l <<
175 * "not supported" here. <<
176 */ <<
177 if (ret && !bdev_write_zeroes_sectors( <<
178 return -EOPNOTSUPP; 249 return -EOPNOTSUPP;
179 return ret; !! 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;
180 } 272 }
181 273
182 /* 274 /*
183 * Convert a number of 512B sectors to a numbe 275 * Convert a number of 512B sectors to a number of pages.
184 * The result is limited to a number of pages 276 * The result is limited to a number of pages that can fit into a BIO.
185 * Also make sure that the result is always at 277 * Also make sure that the result is always at least 1 (page) for the cases
186 * where nr_sects is lower than the number of 278 * where nr_sects is lower than the number of sectors in a page.
187 */ 279 */
188 static unsigned int __blkdev_sectors_to_bio_pa 280 static unsigned int __blkdev_sectors_to_bio_pages(sector_t nr_sects)
189 { 281 {
190 sector_t pages = DIV_ROUND_UP_SECTOR_T 282 sector_t pages = DIV_ROUND_UP_SECTOR_T(nr_sects, PAGE_SIZE / 512);
191 283
192 return min(pages, (sector_t)BIO_MAX_VE !! 284 return min(pages, (sector_t)BIO_MAX_PAGES);
193 } 285 }
194 286
195 static void __blkdev_issue_zero_pages(struct b !! 287 static int __blkdev_issue_zero_pages(struct block_device *bdev,
196 sector_t sector, sector_t nr_s 288 sector_t sector, sector_t nr_sects, gfp_t gfp_mask,
197 struct bio **biop, unsigned in !! 289 struct bio **biop)
198 { 290 {
199 while (nr_sects) { !! 291 struct request_queue *q = bdev_get_queue(bdev);
200 unsigned int nr_vecs = __blkde !! 292 struct bio *bio = *biop;
201 struct bio *bio; !! 293 int bi_size = 0;
202 !! 294 unsigned int sz;
203 bio = bio_alloc(bdev, nr_vecs, <<
204 bio->bi_iter.bi_sector = secto <<
205 295
206 if ((flags & BLKDEV_ZERO_KILLA !! 296 if (!q)
207 fatal_signal_pending(curre !! 297 return -ENXIO;
208 break; <<
209 <<
210 do { <<
211 unsigned int len, adde <<
212 <<
213 len = min_t(sector_t, <<
214 PAGE_SIZE, nr_ <<
215 added = bio_add_page(b <<
216 if (added < len) <<
217 break; <<
218 nr_sects -= added >> S <<
219 sector += added >> SEC <<
220 } while (nr_sects); <<
221 <<
222 *biop = bio_chain_and_submit(* <<
223 cond_resched(); <<
224 } <<
225 } <<
226 298
227 static int blkdev_issue_zero_pages(struct bloc !! 299 if (bdev_read_only(bdev))
228 sector_t nr_sects, gfp_t gfp, !! 300 return -EPERM;
229 { <<
230 struct bio *bio = NULL; <<
231 struct blk_plug plug; <<
232 int ret = 0; <<
233 301
234 if (flags & BLKDEV_ZERO_NOFALLBACK) !! 302 while (nr_sects != 0) {
235 return -EOPNOTSUPP; !! 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);
236 308
237 blk_start_plug(&plug); !! 309 while (nr_sects != 0) {
238 __blkdev_issue_zero_pages(bdev, sector !! 310 sz = min((sector_t) PAGE_SIZE, nr_sects << 9);
239 if (bio) { !! 311 bi_size = bio_add_page(bio, ZERO_PAGE(0), sz, 0);
240 if ((flags & BLKDEV_ZERO_KILLA !! 312 nr_sects -= bi_size >> 9;
241 fatal_signal_pending(curre !! 313 sector += bi_size >> 9;
242 bio_await_chain(bio); !! 314 if (bi_size < sz)
243 blk_finish_plug(&plug) !! 315 break;
244 return -EINTR; <<
245 } 316 }
246 ret = submit_bio_wait(bio); !! 317 cond_resched();
247 bio_put(bio); <<
248 } 318 }
249 blk_finish_plug(&plug); <<
250 319
251 return ret; !! 320 *biop = bio;
>> 321 return 0;
252 } 322 }
253 323
254 /** 324 /**
255 * __blkdev_issue_zeroout - generate number of 325 * __blkdev_issue_zeroout - generate number of zero filed write bios
256 * @bdev: blockdev to issue 326 * @bdev: blockdev to issue
257 * @sector: start sector 327 * @sector: start sector
258 * @nr_sects: number of sectors to write 328 * @nr_sects: number of sectors to write
259 * @gfp_mask: memory allocation flags (for b 329 * @gfp_mask: memory allocation flags (for bio_alloc)
260 * @biop: pointer to anchor bio 330 * @biop: pointer to anchor bio
261 * @flags: controls detailed behavior 331 * @flags: controls detailed behavior
262 * 332 *
263 * Description: 333 * Description:
264 * Zero-fill a block range, either using hard 334 * Zero-fill a block range, either using hardware offload or by explicitly
265 * writing zeroes to the device. 335 * writing zeroes to the device.
266 * 336 *
267 * If a device is using logical block provisi 337 * If a device is using logical block provisioning, the underlying space will
268 * not be released if %flags contains BLKDEV_ 338 * not be released if %flags contains BLKDEV_ZERO_NOUNMAP.
269 * 339 *
270 * If %flags contains BLKDEV_ZERO_NOFALLBACK, 340 * If %flags contains BLKDEV_ZERO_NOFALLBACK, the function will return
271 * -EOPNOTSUPP if no explicit hardware offloa 341 * -EOPNOTSUPP if no explicit hardware offload for zeroing is provided.
272 */ 342 */
273 int __blkdev_issue_zeroout(struct block_device 343 int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
274 sector_t nr_sects, gfp_t gfp_m 344 sector_t nr_sects, gfp_t gfp_mask, struct bio **biop,
275 unsigned flags) 345 unsigned flags)
276 { 346 {
277 sector_t limit = bio_write_zeroes_limi !! 347 int ret;
>> 348 sector_t bs_mask;
278 349
279 if (bdev_read_only(bdev)) !! 350 bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
280 return -EPERM; !! 351 if ((sector | nr_sects) & bs_mask)
>> 352 return -EINVAL;
281 353
282 if (limit) { !! 354 ret = __blkdev_issue_write_zeroes(bdev, sector, nr_sects, gfp_mask,
283 __blkdev_issue_write_zeroes(bd !! 355 biop, flags);
284 gfp_mask, biop !! 356 if (ret != -EOPNOTSUPP || (flags & BLKDEV_ZERO_NOFALLBACK))
285 } else { !! 357 return ret;
286 if (flags & BLKDEV_ZERO_NOFALL !! 358
287 return -EOPNOTSUPP; !! 359 return __blkdev_issue_zero_pages(bdev, sector, nr_sects, gfp_mask,
288 __blkdev_issue_zero_pages(bdev !! 360 biop);
289 biop, flags); <<
290 } <<
291 return 0; <<
292 } 361 }
293 EXPORT_SYMBOL(__blkdev_issue_zeroout); 362 EXPORT_SYMBOL(__blkdev_issue_zeroout);
294 363
295 /** 364 /**
296 * blkdev_issue_zeroout - zero-fill a block ra 365 * blkdev_issue_zeroout - zero-fill a block range
297 * @bdev: blockdev to write 366 * @bdev: blockdev to write
298 * @sector: start sector 367 * @sector: start sector
299 * @nr_sects: number of sectors to write 368 * @nr_sects: number of sectors to write
300 * @gfp_mask: memory allocation flags (for b 369 * @gfp_mask: memory allocation flags (for bio_alloc)
301 * @flags: controls detailed behavior 370 * @flags: controls detailed behavior
302 * 371 *
303 * Description: 372 * Description:
304 * Zero-fill a block range, either using hard 373 * Zero-fill a block range, either using hardware offload or by explicitly
305 * writing zeroes to the device. See __blkde 374 * writing zeroes to the device. See __blkdev_issue_zeroout() for the
306 * valid values for %flags. 375 * valid values for %flags.
307 */ 376 */
308 int blkdev_issue_zeroout(struct block_device * 377 int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
309 sector_t nr_sects, gfp_t gfp_m 378 sector_t nr_sects, gfp_t gfp_mask, unsigned flags)
310 { 379 {
311 int ret; <<
312 <<
313 if ((sector | nr_sects) & ((bdev_logic <<
314 return -EINVAL; <<
315 if (bdev_read_only(bdev)) <<
316 return -EPERM; <<
317 <<
318 if (bdev_write_zeroes_sectors(bdev)) { <<
319 ret = blkdev_issue_write_zeroe <<
320 gfp_mask, flag <<
321 if (ret != -EOPNOTSUPP) <<
322 return ret; <<
323 } <<
324 <<
325 return blkdev_issue_zero_pages(bdev, s <<
326 } <<
327 EXPORT_SYMBOL(blkdev_issue_zeroout); <<
328 <<
329 int blkdev_issue_secure_erase(struct block_dev <<
330 sector_t nr_sects, gfp_t gfp) <<
331 { <<
332 sector_t bs_mask = (bdev_logical_block <<
333 unsigned int max_sectors = bdev_max_se <<
334 struct bio *bio = NULL; <<
335 struct blk_plug plug; <<
336 int ret = 0; 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);
337 385
338 /* make sure that "len << SECTOR_SHIFT !! 386 bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
339 if (max_sectors > UINT_MAX >> SECTOR_S <<
340 max_sectors = UINT_MAX >> SECT <<
341 max_sectors &= ~bs_mask; <<
342 <<
343 if (max_sectors == 0) <<
344 return -EOPNOTSUPP; <<
345 if ((sector | nr_sects) & bs_mask) 387 if ((sector | nr_sects) & bs_mask)
346 return -EINVAL; 388 return -EINVAL;
347 if (bdev_read_only(bdev)) <<
348 return -EPERM; <<
349 389
>> 390 retry:
>> 391 bio = NULL;
350 blk_start_plug(&plug); 392 blk_start_plug(&plug);
351 while (nr_sects) { !! 393 if (try_write_zeroes) {
352 unsigned int len = min_t(secto !! 394 ret = __blkdev_issue_write_zeroes(bdev, sector, nr_sects,
353 !! 395 gfp_mask, &bio, flags);
354 bio = blk_next_bio(bio, bdev, !! 396 } else if (!(flags & BLKDEV_ZERO_NOFALLBACK)) {
355 bio->bi_iter.bi_sector = secto !! 397 ret = __blkdev_issue_zero_pages(bdev, sector, nr_sects,
356 bio->bi_iter.bi_size = len << !! 398 gfp_mask, &bio);
357 !! 399 } else {
358 sector += len; !! 400 /* No zeroing offload support */
359 nr_sects -= len; !! 401 ret = -EOPNOTSUPP;
360 cond_resched(); <<
361 } 402 }
362 if (bio) { !! 403 if (ret == 0 && bio) {
363 ret = submit_bio_wait(bio); 404 ret = submit_bio_wait(bio);
364 bio_put(bio); 405 bio_put(bio);
365 } 406 }
366 blk_finish_plug(&plug); 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 }
367 423
368 return ret; 424 return ret;
369 } 425 }
370 EXPORT_SYMBOL(blkdev_issue_secure_erase); !! 426 EXPORT_SYMBOL(blkdev_issue_zeroout);
371 427
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