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Source at commit 2604e7f9a98c27be50a0c3ff7503b6a5ea8f6cfe created 12 years 7 months ago. By Maarten ter Huurne, cpufreq_stats: Support runtime changes to frequency table | |
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1 | /* |
2 | * bio-integrity.c - bio data integrity extensions |
3 | * |
4 | * Copyright (C) 2007, 2008, 2009 Oracle Corporation |
5 | * Written by: Martin K. Petersen <martin.petersen@oracle.com> |
6 | * |
7 | * This program is free software; you can redistribute it and/or |
8 | * modify it under the terms of the GNU General Public License version |
9 | * 2 as published by the Free Software Foundation. |
10 | * |
11 | * This program is distributed in the hope that it will be useful, but |
12 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
14 | * General Public License for more details. |
15 | * |
16 | * You should have received a copy of the GNU General Public License |
17 | * along with this program; see the file COPYING. If not, write to |
18 | * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, |
19 | * USA. |
20 | * |
21 | */ |
22 | |
23 | #include <linux/blkdev.h> |
24 | #include <linux/mempool.h> |
25 | #include <linux/export.h> |
26 | #include <linux/bio.h> |
27 | #include <linux/workqueue.h> |
28 | #include <linux/slab.h> |
29 | |
30 | struct integrity_slab { |
31 | struct kmem_cache *slab; |
32 | unsigned short nr_vecs; |
33 | char name[8]; |
34 | }; |
35 | |
36 | #define IS(x) { .nr_vecs = x, .name = "bip-"__stringify(x) } |
37 | struct integrity_slab bip_slab[BIOVEC_NR_POOLS] __read_mostly = { |
38 | IS(1), IS(4), IS(16), IS(64), IS(128), IS(BIO_MAX_PAGES), |
39 | }; |
40 | #undef IS |
41 | |
42 | static struct workqueue_struct *kintegrityd_wq; |
43 | |
44 | static inline unsigned int vecs_to_idx(unsigned int nr) |
45 | { |
46 | switch (nr) { |
47 | case 1: |
48 | return 0; |
49 | case 2 ... 4: |
50 | return 1; |
51 | case 5 ... 16: |
52 | return 2; |
53 | case 17 ... 64: |
54 | return 3; |
55 | case 65 ... 128: |
56 | return 4; |
57 | case 129 ... BIO_MAX_PAGES: |
58 | return 5; |
59 | default: |
60 | BUG(); |
61 | } |
62 | } |
63 | |
64 | static inline int use_bip_pool(unsigned int idx) |
65 | { |
66 | if (idx == BIOVEC_MAX_IDX) |
67 | return 1; |
68 | |
69 | return 0; |
70 | } |
71 | |
72 | /** |
73 | * bio_integrity_alloc_bioset - Allocate integrity payload and attach it to bio |
74 | * @bio: bio to attach integrity metadata to |
75 | * @gfp_mask: Memory allocation mask |
76 | * @nr_vecs: Number of integrity metadata scatter-gather elements |
77 | * @bs: bio_set to allocate from |
78 | * |
79 | * Description: This function prepares a bio for attaching integrity |
80 | * metadata. nr_vecs specifies the maximum number of pages containing |
81 | * integrity metadata that can be attached. |
82 | */ |
83 | struct bio_integrity_payload *bio_integrity_alloc_bioset(struct bio *bio, |
84 | gfp_t gfp_mask, |
85 | unsigned int nr_vecs, |
86 | struct bio_set *bs) |
87 | { |
88 | struct bio_integrity_payload *bip; |
89 | unsigned int idx = vecs_to_idx(nr_vecs); |
90 | |
91 | BUG_ON(bio == NULL); |
92 | bip = NULL; |
93 | |
94 | /* Lower order allocations come straight from slab */ |
95 | if (!use_bip_pool(idx)) |
96 | bip = kmem_cache_alloc(bip_slab[idx].slab, gfp_mask); |
97 | |
98 | /* Use mempool if lower order alloc failed or max vecs were requested */ |
99 | if (bip == NULL) { |
100 | idx = BIOVEC_MAX_IDX; /* so we free the payload properly later */ |
101 | bip = mempool_alloc(bs->bio_integrity_pool, gfp_mask); |
102 | |
103 | if (unlikely(bip == NULL)) { |
104 | printk(KERN_ERR "%s: could not alloc bip\n", __func__); |
105 | return NULL; |
106 | } |
107 | } |
108 | |
109 | memset(bip, 0, sizeof(*bip)); |
110 | |
111 | bip->bip_slab = idx; |
112 | bip->bip_bio = bio; |
113 | bio->bi_integrity = bip; |
114 | |
115 | return bip; |
116 | } |
117 | EXPORT_SYMBOL(bio_integrity_alloc_bioset); |
118 | |
119 | /** |
120 | * bio_integrity_alloc - Allocate integrity payload and attach it to bio |
121 | * @bio: bio to attach integrity metadata to |
122 | * @gfp_mask: Memory allocation mask |
123 | * @nr_vecs: Number of integrity metadata scatter-gather elements |
124 | * |
125 | * Description: This function prepares a bio for attaching integrity |
126 | * metadata. nr_vecs specifies the maximum number of pages containing |
127 | * integrity metadata that can be attached. |
128 | */ |
129 | struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio, |
130 | gfp_t gfp_mask, |
131 | unsigned int nr_vecs) |
132 | { |
133 | return bio_integrity_alloc_bioset(bio, gfp_mask, nr_vecs, fs_bio_set); |
134 | } |
135 | EXPORT_SYMBOL(bio_integrity_alloc); |
136 | |
137 | /** |
138 | * bio_integrity_free - Free bio integrity payload |
139 | * @bio: bio containing bip to be freed |
140 | * @bs: bio_set this bio was allocated from |
141 | * |
142 | * Description: Used to free the integrity portion of a bio. Usually |
143 | * called from bio_free(). |
144 | */ |
145 | void bio_integrity_free(struct bio *bio, struct bio_set *bs) |
146 | { |
147 | struct bio_integrity_payload *bip = bio->bi_integrity; |
148 | |
149 | BUG_ON(bip == NULL); |
150 | |
151 | /* A cloned bio doesn't own the integrity metadata */ |
152 | if (!bio_flagged(bio, BIO_CLONED) && !bio_flagged(bio, BIO_FS_INTEGRITY) |
153 | && bip->bip_buf != NULL) |
154 | kfree(bip->bip_buf); |
155 | |
156 | if (use_bip_pool(bip->bip_slab)) |
157 | mempool_free(bip, bs->bio_integrity_pool); |
158 | else |
159 | kmem_cache_free(bip_slab[bip->bip_slab].slab, bip); |
160 | |
161 | bio->bi_integrity = NULL; |
162 | } |
163 | EXPORT_SYMBOL(bio_integrity_free); |
164 | |
165 | /** |
166 | * bio_integrity_add_page - Attach integrity metadata |
167 | * @bio: bio to update |
168 | * @page: page containing integrity metadata |
169 | * @len: number of bytes of integrity metadata in page |
170 | * @offset: start offset within page |
171 | * |
172 | * Description: Attach a page containing integrity metadata to bio. |
173 | */ |
174 | int bio_integrity_add_page(struct bio *bio, struct page *page, |
175 | unsigned int len, unsigned int offset) |
176 | { |
177 | struct bio_integrity_payload *bip = bio->bi_integrity; |
178 | struct bio_vec *iv; |
179 | |
180 | if (bip->bip_vcnt >= bvec_nr_vecs(bip->bip_slab)) { |
181 | printk(KERN_ERR "%s: bip_vec full\n", __func__); |
182 | return 0; |
183 | } |
184 | |
185 | iv = bip_vec_idx(bip, bip->bip_vcnt); |
186 | BUG_ON(iv == NULL); |
187 | |
188 | iv->bv_page = page; |
189 | iv->bv_len = len; |
190 | iv->bv_offset = offset; |
191 | bip->bip_vcnt++; |
192 | |
193 | return len; |
194 | } |
195 | EXPORT_SYMBOL(bio_integrity_add_page); |
196 | |
197 | static int bdev_integrity_enabled(struct block_device *bdev, int rw) |
198 | { |
199 | struct blk_integrity *bi = bdev_get_integrity(bdev); |
200 | |
201 | if (bi == NULL) |
202 | return 0; |
203 | |
204 | if (rw == READ && bi->verify_fn != NULL && |
205 | (bi->flags & INTEGRITY_FLAG_READ)) |
206 | return 1; |
207 | |
208 | if (rw == WRITE && bi->generate_fn != NULL && |
209 | (bi->flags & INTEGRITY_FLAG_WRITE)) |
210 | return 1; |
211 | |
212 | return 0; |
213 | } |
214 | |
215 | /** |
216 | * bio_integrity_enabled - Check whether integrity can be passed |
217 | * @bio: bio to check |
218 | * |
219 | * Description: Determines whether bio_integrity_prep() can be called |
220 | * on this bio or not. bio data direction and target device must be |
221 | * set prior to calling. The functions honors the write_generate and |
222 | * read_verify flags in sysfs. |
223 | */ |
224 | int bio_integrity_enabled(struct bio *bio) |
225 | { |
226 | /* Already protected? */ |
227 | if (bio_integrity(bio)) |
228 | return 0; |
229 | |
230 | return bdev_integrity_enabled(bio->bi_bdev, bio_data_dir(bio)); |
231 | } |
232 | EXPORT_SYMBOL(bio_integrity_enabled); |
233 | |
234 | /** |
235 | * bio_integrity_hw_sectors - Convert 512b sectors to hardware ditto |
236 | * @bi: blk_integrity profile for device |
237 | * @sectors: Number of 512 sectors to convert |
238 | * |
239 | * Description: The block layer calculates everything in 512 byte |
240 | * sectors but integrity metadata is done in terms of the hardware |
241 | * sector size of the storage device. Convert the block layer sectors |
242 | * to physical sectors. |
243 | */ |
244 | static inline unsigned int bio_integrity_hw_sectors(struct blk_integrity *bi, |
245 | unsigned int sectors) |
246 | { |
247 | /* At this point there are only 512b or 4096b DIF/EPP devices */ |
248 | if (bi->sector_size == 4096) |
249 | return sectors >>= 3; |
250 | |
251 | return sectors; |
252 | } |
253 | |
254 | /** |
255 | * bio_integrity_tag_size - Retrieve integrity tag space |
256 | * @bio: bio to inspect |
257 | * |
258 | * Description: Returns the maximum number of tag bytes that can be |
259 | * attached to this bio. Filesystems can use this to determine how |
260 | * much metadata to attach to an I/O. |
261 | */ |
262 | unsigned int bio_integrity_tag_size(struct bio *bio) |
263 | { |
264 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); |
265 | |
266 | BUG_ON(bio->bi_size == 0); |
267 | |
268 | return bi->tag_size * (bio->bi_size / bi->sector_size); |
269 | } |
270 | EXPORT_SYMBOL(bio_integrity_tag_size); |
271 | |
272 | int bio_integrity_tag(struct bio *bio, void *tag_buf, unsigned int len, int set) |
273 | { |
274 | struct bio_integrity_payload *bip = bio->bi_integrity; |
275 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); |
276 | unsigned int nr_sectors; |
277 | |
278 | BUG_ON(bip->bip_buf == NULL); |
279 | |
280 | if (bi->tag_size == 0) |
281 | return -1; |
282 | |
283 | nr_sectors = bio_integrity_hw_sectors(bi, |
284 | DIV_ROUND_UP(len, bi->tag_size)); |
285 | |
286 | if (nr_sectors * bi->tuple_size > bip->bip_size) { |
287 | printk(KERN_ERR "%s: tag too big for bio: %u > %u\n", |
288 | __func__, nr_sectors * bi->tuple_size, bip->bip_size); |
289 | return -1; |
290 | } |
291 | |
292 | if (set) |
293 | bi->set_tag_fn(bip->bip_buf, tag_buf, nr_sectors); |
294 | else |
295 | bi->get_tag_fn(bip->bip_buf, tag_buf, nr_sectors); |
296 | |
297 | return 0; |
298 | } |
299 | |
300 | /** |
301 | * bio_integrity_set_tag - Attach a tag buffer to a bio |
302 | * @bio: bio to attach buffer to |
303 | * @tag_buf: Pointer to a buffer containing tag data |
304 | * @len: Length of the included buffer |
305 | * |
306 | * Description: Use this function to tag a bio by leveraging the extra |
307 | * space provided by devices formatted with integrity protection. The |
308 | * size of the integrity buffer must be <= to the size reported by |
309 | * bio_integrity_tag_size(). |
310 | */ |
311 | int bio_integrity_set_tag(struct bio *bio, void *tag_buf, unsigned int len) |
312 | { |
313 | BUG_ON(bio_data_dir(bio) != WRITE); |
314 | |
315 | return bio_integrity_tag(bio, tag_buf, len, 1); |
316 | } |
317 | EXPORT_SYMBOL(bio_integrity_set_tag); |
318 | |
319 | /** |
320 | * bio_integrity_get_tag - Retrieve a tag buffer from a bio |
321 | * @bio: bio to retrieve buffer from |
322 | * @tag_buf: Pointer to a buffer for the tag data |
323 | * @len: Length of the target buffer |
324 | * |
325 | * Description: Use this function to retrieve the tag buffer from a |
326 | * completed I/O. The size of the integrity buffer must be <= to the |
327 | * size reported by bio_integrity_tag_size(). |
328 | */ |
329 | int bio_integrity_get_tag(struct bio *bio, void *tag_buf, unsigned int len) |
330 | { |
331 | BUG_ON(bio_data_dir(bio) != READ); |
332 | |
333 | return bio_integrity_tag(bio, tag_buf, len, 0); |
334 | } |
335 | EXPORT_SYMBOL(bio_integrity_get_tag); |
336 | |
337 | /** |
338 | * bio_integrity_generate - Generate integrity metadata for a bio |
339 | * @bio: bio to generate integrity metadata for |
340 | * |
341 | * Description: Generates integrity metadata for a bio by calling the |
342 | * block device's generation callback function. The bio must have a |
343 | * bip attached with enough room to accommodate the generated |
344 | * integrity metadata. |
345 | */ |
346 | static void bio_integrity_generate(struct bio *bio) |
347 | { |
348 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); |
349 | struct blk_integrity_exchg bix; |
350 | struct bio_vec *bv; |
351 | sector_t sector = bio->bi_sector; |
352 | unsigned int i, sectors, total; |
353 | void *prot_buf = bio->bi_integrity->bip_buf; |
354 | |
355 | total = 0; |
356 | bix.disk_name = bio->bi_bdev->bd_disk->disk_name; |
357 | bix.sector_size = bi->sector_size; |
358 | |
359 | bio_for_each_segment(bv, bio, i) { |
360 | void *kaddr = kmap_atomic(bv->bv_page); |
361 | bix.data_buf = kaddr + bv->bv_offset; |
362 | bix.data_size = bv->bv_len; |
363 | bix.prot_buf = prot_buf; |
364 | bix.sector = sector; |
365 | |
366 | bi->generate_fn(&bix); |
367 | |
368 | sectors = bv->bv_len / bi->sector_size; |
369 | sector += sectors; |
370 | prot_buf += sectors * bi->tuple_size; |
371 | total += sectors * bi->tuple_size; |
372 | BUG_ON(total > bio->bi_integrity->bip_size); |
373 | |
374 | kunmap_atomic(kaddr); |
375 | } |
376 | } |
377 | |
378 | static inline unsigned short blk_integrity_tuple_size(struct blk_integrity *bi) |
379 | { |
380 | if (bi) |
381 | return bi->tuple_size; |
382 | |
383 | return 0; |
384 | } |
385 | |
386 | /** |
387 | * bio_integrity_prep - Prepare bio for integrity I/O |
388 | * @bio: bio to prepare |
389 | * |
390 | * Description: Allocates a buffer for integrity metadata, maps the |
391 | * pages and attaches them to a bio. The bio must have data |
392 | * direction, target device and start sector set priot to calling. In |
393 | * the WRITE case, integrity metadata will be generated using the |
394 | * block device's integrity function. In the READ case, the buffer |
395 | * will be prepared for DMA and a suitable end_io handler set up. |
396 | */ |
397 | int bio_integrity_prep(struct bio *bio) |
398 | { |
399 | struct bio_integrity_payload *bip; |
400 | struct blk_integrity *bi; |
401 | struct request_queue *q; |
402 | void *buf; |
403 | unsigned long start, end; |
404 | unsigned int len, nr_pages; |
405 | unsigned int bytes, offset, i; |
406 | unsigned int sectors; |
407 | |
408 | bi = bdev_get_integrity(bio->bi_bdev); |
409 | q = bdev_get_queue(bio->bi_bdev); |
410 | BUG_ON(bi == NULL); |
411 | BUG_ON(bio_integrity(bio)); |
412 | |
413 | sectors = bio_integrity_hw_sectors(bi, bio_sectors(bio)); |
414 | |
415 | /* Allocate kernel buffer for protection data */ |
416 | len = sectors * blk_integrity_tuple_size(bi); |
417 | buf = kmalloc(len, GFP_NOIO | q->bounce_gfp); |
418 | if (unlikely(buf == NULL)) { |
419 | printk(KERN_ERR "could not allocate integrity buffer\n"); |
420 | return -ENOMEM; |
421 | } |
422 | |
423 | end = (((unsigned long) buf) + len + PAGE_SIZE - 1) >> PAGE_SHIFT; |
424 | start = ((unsigned long) buf) >> PAGE_SHIFT; |
425 | nr_pages = end - start; |
426 | |
427 | /* Allocate bio integrity payload and integrity vectors */ |
428 | bip = bio_integrity_alloc(bio, GFP_NOIO, nr_pages); |
429 | if (unlikely(bip == NULL)) { |
430 | printk(KERN_ERR "could not allocate data integrity bioset\n"); |
431 | kfree(buf); |
432 | return -EIO; |
433 | } |
434 | |
435 | bip->bip_buf = buf; |
436 | bip->bip_size = len; |
437 | bip->bip_sector = bio->bi_sector; |
438 | |
439 | /* Map it */ |
440 | offset = offset_in_page(buf); |
441 | for (i = 0 ; i < nr_pages ; i++) { |
442 | int ret; |
443 | bytes = PAGE_SIZE - offset; |
444 | |
445 | if (len <= 0) |
446 | break; |
447 | |
448 | if (bytes > len) |
449 | bytes = len; |
450 | |
451 | ret = bio_integrity_add_page(bio, virt_to_page(buf), |
452 | bytes, offset); |
453 | |
454 | if (ret == 0) |
455 | return 0; |
456 | |
457 | if (ret < bytes) |
458 | break; |
459 | |
460 | buf += bytes; |
461 | len -= bytes; |
462 | offset = 0; |
463 | } |
464 | |
465 | /* Install custom I/O completion handler if read verify is enabled */ |
466 | if (bio_data_dir(bio) == READ) { |
467 | bip->bip_end_io = bio->bi_end_io; |
468 | bio->bi_end_io = bio_integrity_endio; |
469 | } |
470 | |
471 | /* Auto-generate integrity metadata if this is a write */ |
472 | if (bio_data_dir(bio) == WRITE) |
473 | bio_integrity_generate(bio); |
474 | |
475 | return 0; |
476 | } |
477 | EXPORT_SYMBOL(bio_integrity_prep); |
478 | |
479 | /** |
480 | * bio_integrity_verify - Verify integrity metadata for a bio |
481 | * @bio: bio to verify |
482 | * |
483 | * Description: This function is called to verify the integrity of a |
484 | * bio. The data in the bio io_vec is compared to the integrity |
485 | * metadata returned by the HBA. |
486 | */ |
487 | static int bio_integrity_verify(struct bio *bio) |
488 | { |
489 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); |
490 | struct blk_integrity_exchg bix; |
491 | struct bio_vec *bv; |
492 | sector_t sector = bio->bi_integrity->bip_sector; |
493 | unsigned int i, sectors, total, ret; |
494 | void *prot_buf = bio->bi_integrity->bip_buf; |
495 | |
496 | ret = total = 0; |
497 | bix.disk_name = bio->bi_bdev->bd_disk->disk_name; |
498 | bix.sector_size = bi->sector_size; |
499 | |
500 | bio_for_each_segment(bv, bio, i) { |
501 | void *kaddr = kmap_atomic(bv->bv_page); |
502 | bix.data_buf = kaddr + bv->bv_offset; |
503 | bix.data_size = bv->bv_len; |
504 | bix.prot_buf = prot_buf; |
505 | bix.sector = sector; |
506 | |
507 | ret = bi->verify_fn(&bix); |
508 | |
509 | if (ret) { |
510 | kunmap_atomic(kaddr); |
511 | return ret; |
512 | } |
513 | |
514 | sectors = bv->bv_len / bi->sector_size; |
515 | sector += sectors; |
516 | prot_buf += sectors * bi->tuple_size; |
517 | total += sectors * bi->tuple_size; |
518 | BUG_ON(total > bio->bi_integrity->bip_size); |
519 | |
520 | kunmap_atomic(kaddr); |
521 | } |
522 | |
523 | return ret; |
524 | } |
525 | |
526 | /** |
527 | * bio_integrity_verify_fn - Integrity I/O completion worker |
528 | * @work: Work struct stored in bio to be verified |
529 | * |
530 | * Description: This workqueue function is called to complete a READ |
531 | * request. The function verifies the transferred integrity metadata |
532 | * and then calls the original bio end_io function. |
533 | */ |
534 | static void bio_integrity_verify_fn(struct work_struct *work) |
535 | { |
536 | struct bio_integrity_payload *bip = |
537 | container_of(work, struct bio_integrity_payload, bip_work); |
538 | struct bio *bio = bip->bip_bio; |
539 | int error; |
540 | |
541 | error = bio_integrity_verify(bio); |
542 | |
543 | /* Restore original bio completion handler */ |
544 | bio->bi_end_io = bip->bip_end_io; |
545 | bio_endio(bio, error); |
546 | } |
547 | |
548 | /** |
549 | * bio_integrity_endio - Integrity I/O completion function |
550 | * @bio: Protected bio |
551 | * @error: Pointer to errno |
552 | * |
553 | * Description: Completion for integrity I/O |
554 | * |
555 | * Normally I/O completion is done in interrupt context. However, |
556 | * verifying I/O integrity is a time-consuming task which must be run |
557 | * in process context. This function postpones completion |
558 | * accordingly. |
559 | */ |
560 | void bio_integrity_endio(struct bio *bio, int error) |
561 | { |
562 | struct bio_integrity_payload *bip = bio->bi_integrity; |
563 | |
564 | BUG_ON(bip->bip_bio != bio); |
565 | |
566 | /* In case of an I/O error there is no point in verifying the |
567 | * integrity metadata. Restore original bio end_io handler |
568 | * and run it. |
569 | */ |
570 | if (error) { |
571 | bio->bi_end_io = bip->bip_end_io; |
572 | bio_endio(bio, error); |
573 | |
574 | return; |
575 | } |
576 | |
577 | INIT_WORK(&bip->bip_work, bio_integrity_verify_fn); |
578 | queue_work(kintegrityd_wq, &bip->bip_work); |
579 | } |
580 | EXPORT_SYMBOL(bio_integrity_endio); |
581 | |
582 | /** |
583 | * bio_integrity_mark_head - Advance bip_vec skip bytes |
584 | * @bip: Integrity vector to advance |
585 | * @skip: Number of bytes to advance it |
586 | */ |
587 | void bio_integrity_mark_head(struct bio_integrity_payload *bip, |
588 | unsigned int skip) |
589 | { |
590 | struct bio_vec *iv; |
591 | unsigned int i; |
592 | |
593 | bip_for_each_vec(iv, bip, i) { |
594 | if (skip == 0) { |
595 | bip->bip_idx = i; |
596 | return; |
597 | } else if (skip >= iv->bv_len) { |
598 | skip -= iv->bv_len; |
599 | } else { /* skip < iv->bv_len) */ |
600 | iv->bv_offset += skip; |
601 | iv->bv_len -= skip; |
602 | bip->bip_idx = i; |
603 | return; |
604 | } |
605 | } |
606 | } |
607 | |
608 | /** |
609 | * bio_integrity_mark_tail - Truncate bip_vec to be len bytes long |
610 | * @bip: Integrity vector to truncate |
611 | * @len: New length of integrity vector |
612 | */ |
613 | void bio_integrity_mark_tail(struct bio_integrity_payload *bip, |
614 | unsigned int len) |
615 | { |
616 | struct bio_vec *iv; |
617 | unsigned int i; |
618 | |
619 | bip_for_each_vec(iv, bip, i) { |
620 | if (len == 0) { |
621 | bip->bip_vcnt = i; |
622 | return; |
623 | } else if (len >= iv->bv_len) { |
624 | len -= iv->bv_len; |
625 | } else { /* len < iv->bv_len) */ |
626 | iv->bv_len = len; |
627 | len = 0; |
628 | } |
629 | } |
630 | } |
631 | |
632 | /** |
633 | * bio_integrity_advance - Advance integrity vector |
634 | * @bio: bio whose integrity vector to update |
635 | * @bytes_done: number of data bytes that have been completed |
636 | * |
637 | * Description: This function calculates how many integrity bytes the |
638 | * number of completed data bytes correspond to and advances the |
639 | * integrity vector accordingly. |
640 | */ |
641 | void bio_integrity_advance(struct bio *bio, unsigned int bytes_done) |
642 | { |
643 | struct bio_integrity_payload *bip = bio->bi_integrity; |
644 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); |
645 | unsigned int nr_sectors; |
646 | |
647 | BUG_ON(bip == NULL); |
648 | BUG_ON(bi == NULL); |
649 | |
650 | nr_sectors = bio_integrity_hw_sectors(bi, bytes_done >> 9); |
651 | bio_integrity_mark_head(bip, nr_sectors * bi->tuple_size); |
652 | } |
653 | EXPORT_SYMBOL(bio_integrity_advance); |
654 | |
655 | /** |
656 | * bio_integrity_trim - Trim integrity vector |
657 | * @bio: bio whose integrity vector to update |
658 | * @offset: offset to first data sector |
659 | * @sectors: number of data sectors |
660 | * |
661 | * Description: Used to trim the integrity vector in a cloned bio. |
662 | * The ivec will be advanced corresponding to 'offset' data sectors |
663 | * and the length will be truncated corresponding to 'len' data |
664 | * sectors. |
665 | */ |
666 | void bio_integrity_trim(struct bio *bio, unsigned int offset, |
667 | unsigned int sectors) |
668 | { |
669 | struct bio_integrity_payload *bip = bio->bi_integrity; |
670 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); |
671 | unsigned int nr_sectors; |
672 | |
673 | BUG_ON(bip == NULL); |
674 | BUG_ON(bi == NULL); |
675 | BUG_ON(!bio_flagged(bio, BIO_CLONED)); |
676 | |
677 | nr_sectors = bio_integrity_hw_sectors(bi, sectors); |
678 | bip->bip_sector = bip->bip_sector + offset; |
679 | bio_integrity_mark_head(bip, offset * bi->tuple_size); |
680 | bio_integrity_mark_tail(bip, sectors * bi->tuple_size); |
681 | } |
682 | EXPORT_SYMBOL(bio_integrity_trim); |
683 | |
684 | /** |
685 | * bio_integrity_split - Split integrity metadata |
686 | * @bio: Protected bio |
687 | * @bp: Resulting bio_pair |
688 | * @sectors: Offset |
689 | * |
690 | * Description: Splits an integrity page into a bio_pair. |
691 | */ |
692 | void bio_integrity_split(struct bio *bio, struct bio_pair *bp, int sectors) |
693 | { |
694 | struct blk_integrity *bi; |
695 | struct bio_integrity_payload *bip = bio->bi_integrity; |
696 | unsigned int nr_sectors; |
697 | |
698 | if (bio_integrity(bio) == 0) |
699 | return; |
700 | |
701 | bi = bdev_get_integrity(bio->bi_bdev); |
702 | BUG_ON(bi == NULL); |
703 | BUG_ON(bip->bip_vcnt != 1); |
704 | |
705 | nr_sectors = bio_integrity_hw_sectors(bi, sectors); |
706 | |
707 | bp->bio1.bi_integrity = &bp->bip1; |
708 | bp->bio2.bi_integrity = &bp->bip2; |
709 | |
710 | bp->iv1 = bip->bip_vec[0]; |
711 | bp->iv2 = bip->bip_vec[0]; |
712 | |
713 | bp->bip1.bip_vec[0] = bp->iv1; |
714 | bp->bip2.bip_vec[0] = bp->iv2; |
715 | |
716 | bp->iv1.bv_len = sectors * bi->tuple_size; |
717 | bp->iv2.bv_offset += sectors * bi->tuple_size; |
718 | bp->iv2.bv_len -= sectors * bi->tuple_size; |
719 | |
720 | bp->bip1.bip_sector = bio->bi_integrity->bip_sector; |
721 | bp->bip2.bip_sector = bio->bi_integrity->bip_sector + nr_sectors; |
722 | |
723 | bp->bip1.bip_vcnt = bp->bip2.bip_vcnt = 1; |
724 | bp->bip1.bip_idx = bp->bip2.bip_idx = 0; |
725 | } |
726 | EXPORT_SYMBOL(bio_integrity_split); |
727 | |
728 | /** |
729 | * bio_integrity_clone - Callback for cloning bios with integrity metadata |
730 | * @bio: New bio |
731 | * @bio_src: Original bio |
732 | * @gfp_mask: Memory allocation mask |
733 | * @bs: bio_set to allocate bip from |
734 | * |
735 | * Description: Called to allocate a bip when cloning a bio |
736 | */ |
737 | int bio_integrity_clone(struct bio *bio, struct bio *bio_src, |
738 | gfp_t gfp_mask, struct bio_set *bs) |
739 | { |
740 | struct bio_integrity_payload *bip_src = bio_src->bi_integrity; |
741 | struct bio_integrity_payload *bip; |
742 | |
743 | BUG_ON(bip_src == NULL); |
744 | |
745 | bip = bio_integrity_alloc_bioset(bio, gfp_mask, bip_src->bip_vcnt, bs); |
746 | |
747 | if (bip == NULL) |
748 | return -EIO; |
749 | |
750 | memcpy(bip->bip_vec, bip_src->bip_vec, |
751 | bip_src->bip_vcnt * sizeof(struct bio_vec)); |
752 | |
753 | bip->bip_sector = bip_src->bip_sector; |
754 | bip->bip_vcnt = bip_src->bip_vcnt; |
755 | bip->bip_idx = bip_src->bip_idx; |
756 | |
757 | return 0; |
758 | } |
759 | EXPORT_SYMBOL(bio_integrity_clone); |
760 | |
761 | int bioset_integrity_create(struct bio_set *bs, int pool_size) |
762 | { |
763 | unsigned int max_slab = vecs_to_idx(BIO_MAX_PAGES); |
764 | |
765 | if (bs->bio_integrity_pool) |
766 | return 0; |
767 | |
768 | bs->bio_integrity_pool = |
769 | mempool_create_slab_pool(pool_size, bip_slab[max_slab].slab); |
770 | |
771 | if (!bs->bio_integrity_pool) |
772 | return -1; |
773 | |
774 | return 0; |
775 | } |
776 | EXPORT_SYMBOL(bioset_integrity_create); |
777 | |
778 | void bioset_integrity_free(struct bio_set *bs) |
779 | { |
780 | if (bs->bio_integrity_pool) |
781 | mempool_destroy(bs->bio_integrity_pool); |
782 | } |
783 | EXPORT_SYMBOL(bioset_integrity_free); |
784 | |
785 | void __init bio_integrity_init(void) |
786 | { |
787 | unsigned int i; |
788 | |
789 | /* |
790 | * kintegrityd won't block much but may burn a lot of CPU cycles. |
791 | * Make it highpri CPU intensive wq with max concurrency of 1. |
792 | */ |
793 | kintegrityd_wq = alloc_workqueue("kintegrityd", WQ_MEM_RECLAIM | |
794 | WQ_HIGHPRI | WQ_CPU_INTENSIVE, 1); |
795 | if (!kintegrityd_wq) |
796 | panic("Failed to create kintegrityd\n"); |
797 | |
798 | for (i = 0 ; i < BIOVEC_NR_POOLS ; i++) { |
799 | unsigned int size; |
800 | |
801 | size = sizeof(struct bio_integrity_payload) |
802 | + bip_slab[i].nr_vecs * sizeof(struct bio_vec); |
803 | |
804 | bip_slab[i].slab = |
805 | kmem_cache_create(bip_slab[i].name, size, 0, |
806 | SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); |
807 | } |
808 | } |
809 |
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