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