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