blob: 19caf7c962ace6c58868ed4fd2196212faf755ef [file] [log] [blame]
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001/*
2 * bio-integrity.c - bio data integrity extensions
3 *
4 * Copyright (C) 2007, 2008 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/bio.h>
26#include <linux/workqueue.h>
27
28static struct kmem_cache *bio_integrity_slab __read_mostly;
29static struct workqueue_struct *kintegrityd_wq;
30
31/**
32 * bio_integrity_alloc_bioset - Allocate integrity payload and attach it to bio
33 * @bio: bio to attach integrity metadata to
34 * @gfp_mask: Memory allocation mask
35 * @nr_vecs: Number of integrity metadata scatter-gather elements
36 * @bs: bio_set to allocate from
37 *
38 * Description: This function prepares a bio for attaching integrity
39 * metadata. nr_vecs specifies the maximum number of pages containing
40 * integrity metadata that can be attached.
41 */
Jens Axboeb9846792008-06-17 19:05:48 +020042struct bio_integrity_payload *bio_integrity_alloc_bioset(struct bio *bio,
43 gfp_t gfp_mask,
44 unsigned int nr_vecs,
45 struct bio_set *bs)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +020046{
47 struct bio_integrity_payload *bip;
48 struct bio_vec *iv;
49 unsigned long idx;
50
51 BUG_ON(bio == NULL);
52
53 bip = mempool_alloc(bs->bio_integrity_pool, gfp_mask);
54 if (unlikely(bip == NULL)) {
55 printk(KERN_ERR "%s: could not alloc bip\n", __func__);
56 return NULL;
57 }
58
59 memset(bip, 0, sizeof(*bip));
60
61 iv = bvec_alloc_bs(gfp_mask, nr_vecs, &idx, bs);
62 if (unlikely(iv == NULL)) {
63 printk(KERN_ERR "%s: could not alloc bip_vec\n", __func__);
64 mempool_free(bip, bs->bio_integrity_pool);
65 return NULL;
66 }
67
68 bip->bip_pool = idx;
69 bip->bip_vec = iv;
70 bip->bip_bio = bio;
71 bio->bi_integrity = bip;
72
73 return bip;
74}
75EXPORT_SYMBOL(bio_integrity_alloc_bioset);
76
77/**
78 * bio_integrity_alloc - Allocate integrity payload and attach it to bio
79 * @bio: bio to attach integrity metadata to
80 * @gfp_mask: Memory allocation mask
81 * @nr_vecs: Number of integrity metadata scatter-gather elements
82 *
83 * Description: This function prepares a bio for attaching integrity
84 * metadata. nr_vecs specifies the maximum number of pages containing
85 * integrity metadata that can be attached.
86 */
Jens Axboeb9846792008-06-17 19:05:48 +020087struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio,
88 gfp_t gfp_mask,
89 unsigned int nr_vecs)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +020090{
91 return bio_integrity_alloc_bioset(bio, gfp_mask, nr_vecs, fs_bio_set);
92}
93EXPORT_SYMBOL(bio_integrity_alloc);
94
95/**
96 * bio_integrity_free - Free bio integrity payload
97 * @bio: bio containing bip to be freed
98 * @bs: bio_set this bio was allocated from
99 *
100 * Description: Used to free the integrity portion of a bio. Usually
101 * called from bio_free().
102 */
103void bio_integrity_free(struct bio *bio, struct bio_set *bs)
104{
105 struct bio_integrity_payload *bip = bio->bi_integrity;
106
107 BUG_ON(bip == NULL);
108
109 /* A cloned bio doesn't own the integrity metadata */
Martin K. Petersen74aa8c22008-10-01 03:38:37 -0400110 if (!bio_flagged(bio, BIO_CLONED) && !bio_flagged(bio, BIO_FS_INTEGRITY)
111 && bip->bip_buf != NULL)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200112 kfree(bip->bip_buf);
113
114 mempool_free(bip->bip_vec, bs->bvec_pools[bip->bip_pool]);
115 mempool_free(bip, bs->bio_integrity_pool);
116
117 bio->bi_integrity = NULL;
118}
119EXPORT_SYMBOL(bio_integrity_free);
120
121/**
122 * bio_integrity_add_page - Attach integrity metadata
123 * @bio: bio to update
124 * @page: page containing integrity metadata
125 * @len: number of bytes of integrity metadata in page
126 * @offset: start offset within page
127 *
128 * Description: Attach a page containing integrity metadata to bio.
129 */
130int bio_integrity_add_page(struct bio *bio, struct page *page,
131 unsigned int len, unsigned int offset)
132{
133 struct bio_integrity_payload *bip = bio->bi_integrity;
134 struct bio_vec *iv;
135
136 if (bip->bip_vcnt >= bvec_nr_vecs(bip->bip_pool)) {
137 printk(KERN_ERR "%s: bip_vec full\n", __func__);
138 return 0;
139 }
140
141 iv = bip_vec_idx(bip, bip->bip_vcnt);
142 BUG_ON(iv == NULL);
143 BUG_ON(iv->bv_page != NULL);
144
145 iv->bv_page = page;
146 iv->bv_len = len;
147 iv->bv_offset = offset;
148 bip->bip_vcnt++;
149
150 return len;
151}
152EXPORT_SYMBOL(bio_integrity_add_page);
153
Jens Axboe9c02f2b2008-09-18 09:31:53 -0700154static int bdev_integrity_enabled(struct block_device *bdev, int rw)
155{
156 struct blk_integrity *bi = bdev_get_integrity(bdev);
157
158 if (bi == NULL)
159 return 0;
160
161 if (rw == READ && bi->verify_fn != NULL &&
162 (bi->flags & INTEGRITY_FLAG_READ))
163 return 1;
164
165 if (rw == WRITE && bi->generate_fn != NULL &&
166 (bi->flags & INTEGRITY_FLAG_WRITE))
167 return 1;
168
169 return 0;
170}
171
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200172/**
173 * bio_integrity_enabled - Check whether integrity can be passed
174 * @bio: bio to check
175 *
176 * Description: Determines whether bio_integrity_prep() can be called
177 * on this bio or not. bio data direction and target device must be
178 * set prior to calling. The functions honors the write_generate and
179 * read_verify flags in sysfs.
180 */
181int bio_integrity_enabled(struct bio *bio)
182{
183 /* Already protected? */
184 if (bio_integrity(bio))
185 return 0;
186
187 return bdev_integrity_enabled(bio->bi_bdev, bio_data_dir(bio));
188}
189EXPORT_SYMBOL(bio_integrity_enabled);
190
191/**
192 * bio_integrity_hw_sectors - Convert 512b sectors to hardware ditto
193 * @bi: blk_integrity profile for device
194 * @sectors: Number of 512 sectors to convert
195 *
196 * Description: The block layer calculates everything in 512 byte
197 * sectors but integrity metadata is done in terms of the hardware
198 * sector size of the storage device. Convert the block layer sectors
199 * to physical sectors.
200 */
Jens Axboeb9846792008-06-17 19:05:48 +0200201static inline unsigned int bio_integrity_hw_sectors(struct blk_integrity *bi,
202 unsigned int sectors)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200203{
204 /* At this point there are only 512b or 4096b DIF/EPP devices */
205 if (bi->sector_size == 4096)
206 return sectors >>= 3;
207
208 return sectors;
209}
210
211/**
212 * bio_integrity_tag_size - Retrieve integrity tag space
213 * @bio: bio to inspect
214 *
215 * Description: Returns the maximum number of tag bytes that can be
216 * attached to this bio. Filesystems can use this to determine how
217 * much metadata to attach to an I/O.
218 */
219unsigned int bio_integrity_tag_size(struct bio *bio)
220{
221 struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
222
223 BUG_ON(bio->bi_size == 0);
224
225 return bi->tag_size * (bio->bi_size / bi->sector_size);
226}
227EXPORT_SYMBOL(bio_integrity_tag_size);
228
229int bio_integrity_tag(struct bio *bio, void *tag_buf, unsigned int len, int set)
230{
231 struct bio_integrity_payload *bip = bio->bi_integrity;
232 struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
233 unsigned int nr_sectors;
234
235 BUG_ON(bip->bip_buf == NULL);
236
237 if (bi->tag_size == 0)
238 return -1;
239
Jens Axboeb9846792008-06-17 19:05:48 +0200240 nr_sectors = bio_integrity_hw_sectors(bi,
241 DIV_ROUND_UP(len, bi->tag_size));
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200242
243 if (nr_sectors * bi->tuple_size > bip->bip_size) {
244 printk(KERN_ERR "%s: tag too big for bio: %u > %u\n",
245 __func__, nr_sectors * bi->tuple_size, bip->bip_size);
246 return -1;
247 }
248
249 if (set)
250 bi->set_tag_fn(bip->bip_buf, tag_buf, nr_sectors);
251 else
252 bi->get_tag_fn(bip->bip_buf, tag_buf, nr_sectors);
253
254 return 0;
255}
256
257/**
258 * bio_integrity_set_tag - Attach a tag buffer to a bio
259 * @bio: bio to attach buffer to
260 * @tag_buf: Pointer to a buffer containing tag data
261 * @len: Length of the included buffer
262 *
263 * Description: Use this function to tag a bio by leveraging the extra
264 * space provided by devices formatted with integrity protection. The
265 * size of the integrity buffer must be <= to the size reported by
266 * bio_integrity_tag_size().
267 */
268int bio_integrity_set_tag(struct bio *bio, void *tag_buf, unsigned int len)
269{
270 BUG_ON(bio_data_dir(bio) != WRITE);
271
272 return bio_integrity_tag(bio, tag_buf, len, 1);
273}
274EXPORT_SYMBOL(bio_integrity_set_tag);
275
276/**
277 * bio_integrity_get_tag - Retrieve a tag buffer from a bio
278 * @bio: bio to retrieve buffer from
279 * @tag_buf: Pointer to a buffer for the tag data
280 * @len: Length of the target buffer
281 *
282 * Description: Use this function to retrieve the tag buffer from a
283 * completed I/O. The size of the integrity buffer must be <= to the
284 * size reported by bio_integrity_tag_size().
285 */
286int bio_integrity_get_tag(struct bio *bio, void *tag_buf, unsigned int len)
287{
288 BUG_ON(bio_data_dir(bio) != READ);
289
290 return bio_integrity_tag(bio, tag_buf, len, 0);
291}
292EXPORT_SYMBOL(bio_integrity_get_tag);
293
294/**
295 * bio_integrity_generate - Generate integrity metadata for a bio
296 * @bio: bio to generate integrity metadata for
297 *
298 * Description: Generates integrity metadata for a bio by calling the
299 * block device's generation callback function. The bio must have a
300 * bip attached with enough room to accommodate the generated
301 * integrity metadata.
302 */
303static void bio_integrity_generate(struct bio *bio)
304{
305 struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
306 struct blk_integrity_exchg bix;
307 struct bio_vec *bv;
308 sector_t sector = bio->bi_sector;
309 unsigned int i, sectors, total;
310 void *prot_buf = bio->bi_integrity->bip_buf;
311
312 total = 0;
313 bix.disk_name = bio->bi_bdev->bd_disk->disk_name;
314 bix.sector_size = bi->sector_size;
315
316 bio_for_each_segment(bv, bio, i) {
317 void *kaddr = kmap_atomic(bv->bv_page, KM_USER0);
318 bix.data_buf = kaddr + bv->bv_offset;
319 bix.data_size = bv->bv_len;
320 bix.prot_buf = prot_buf;
321 bix.sector = sector;
322
323 bi->generate_fn(&bix);
324
325 sectors = bv->bv_len / bi->sector_size;
326 sector += sectors;
327 prot_buf += sectors * bi->tuple_size;
328 total += sectors * bi->tuple_size;
329 BUG_ON(total > bio->bi_integrity->bip_size);
330
331 kunmap_atomic(kaddr, KM_USER0);
332 }
333}
334
Jens Axboe9c02f2b2008-09-18 09:31:53 -0700335static inline unsigned short blk_integrity_tuple_size(struct blk_integrity *bi)
336{
337 if (bi)
338 return bi->tuple_size;
339
340 return 0;
341}
342
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200343/**
344 * bio_integrity_prep - Prepare bio for integrity I/O
345 * @bio: bio to prepare
346 *
347 * Description: Allocates a buffer for integrity metadata, maps the
348 * pages and attaches them to a bio. The bio must have data
349 * direction, target device and start sector set priot to calling. In
350 * the WRITE case, integrity metadata will be generated using the
351 * block device's integrity function. In the READ case, the buffer
352 * will be prepared for DMA and a suitable end_io handler set up.
353 */
354int bio_integrity_prep(struct bio *bio)
355{
356 struct bio_integrity_payload *bip;
357 struct blk_integrity *bi;
358 struct request_queue *q;
359 void *buf;
360 unsigned long start, end;
361 unsigned int len, nr_pages;
362 unsigned int bytes, offset, i;
363 unsigned int sectors;
364
365 bi = bdev_get_integrity(bio->bi_bdev);
366 q = bdev_get_queue(bio->bi_bdev);
367 BUG_ON(bi == NULL);
368 BUG_ON(bio_integrity(bio));
369
370 sectors = bio_integrity_hw_sectors(bi, bio_sectors(bio));
371
372 /* Allocate kernel buffer for protection data */
373 len = sectors * blk_integrity_tuple_size(bi);
374 buf = kmalloc(len, GFP_NOIO | __GFP_NOFAIL | q->bounce_gfp);
375 if (unlikely(buf == NULL)) {
376 printk(KERN_ERR "could not allocate integrity buffer\n");
377 return -EIO;
378 }
379
380 end = (((unsigned long) buf) + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
381 start = ((unsigned long) buf) >> PAGE_SHIFT;
382 nr_pages = end - start;
383
384 /* Allocate bio integrity payload and integrity vectors */
385 bip = bio_integrity_alloc(bio, GFP_NOIO, nr_pages);
386 if (unlikely(bip == NULL)) {
387 printk(KERN_ERR "could not allocate data integrity bioset\n");
388 kfree(buf);
389 return -EIO;
390 }
391
392 bip->bip_buf = buf;
393 bip->bip_size = len;
394 bip->bip_sector = bio->bi_sector;
395
396 /* Map it */
397 offset = offset_in_page(buf);
398 for (i = 0 ; i < nr_pages ; i++) {
399 int ret;
400 bytes = PAGE_SIZE - offset;
401
402 if (len <= 0)
403 break;
404
405 if (bytes > len)
406 bytes = len;
407
408 ret = bio_integrity_add_page(bio, virt_to_page(buf),
409 bytes, offset);
410
411 if (ret == 0)
412 return 0;
413
414 if (ret < bytes)
415 break;
416
417 buf += bytes;
418 len -= bytes;
419 offset = 0;
420 }
421
422 /* Install custom I/O completion handler if read verify is enabled */
423 if (bio_data_dir(bio) == READ) {
424 bip->bip_end_io = bio->bi_end_io;
425 bio->bi_end_io = bio_integrity_endio;
426 }
427
428 /* Auto-generate integrity metadata if this is a write */
429 if (bio_data_dir(bio) == WRITE)
430 bio_integrity_generate(bio);
431
432 return 0;
433}
434EXPORT_SYMBOL(bio_integrity_prep);
435
436/**
437 * bio_integrity_verify - Verify integrity metadata for a bio
438 * @bio: bio to verify
439 *
440 * Description: This function is called to verify the integrity of a
441 * bio. The data in the bio io_vec is compared to the integrity
442 * metadata returned by the HBA.
443 */
444static int bio_integrity_verify(struct bio *bio)
445{
446 struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
447 struct blk_integrity_exchg bix;
448 struct bio_vec *bv;
449 sector_t sector = bio->bi_integrity->bip_sector;
450 unsigned int i, sectors, total, ret;
451 void *prot_buf = bio->bi_integrity->bip_buf;
452
453 ret = total = 0;
454 bix.disk_name = bio->bi_bdev->bd_disk->disk_name;
455 bix.sector_size = bi->sector_size;
456
457 bio_for_each_segment(bv, bio, i) {
458 void *kaddr = kmap_atomic(bv->bv_page, KM_USER0);
459 bix.data_buf = kaddr + bv->bv_offset;
460 bix.data_size = bv->bv_len;
461 bix.prot_buf = prot_buf;
462 bix.sector = sector;
463
464 ret = bi->verify_fn(&bix);
465
466 if (ret) {
467 kunmap_atomic(kaddr, KM_USER0);
468 break;
469 }
470
471 sectors = bv->bv_len / bi->sector_size;
472 sector += sectors;
473 prot_buf += sectors * bi->tuple_size;
474 total += sectors * bi->tuple_size;
475 BUG_ON(total > bio->bi_integrity->bip_size);
476
477 kunmap_atomic(kaddr, KM_USER0);
478 }
479
480 return ret;
481}
482
483/**
484 * bio_integrity_verify_fn - Integrity I/O completion worker
485 * @work: Work struct stored in bio to be verified
486 *
487 * Description: This workqueue function is called to complete a READ
488 * request. The function verifies the transferred integrity metadata
489 * and then calls the original bio end_io function.
490 */
491static void bio_integrity_verify_fn(struct work_struct *work)
492{
Jens Axboeb9846792008-06-17 19:05:48 +0200493 struct bio_integrity_payload *bip =
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200494 container_of(work, struct bio_integrity_payload, bip_work);
495 struct bio *bio = bip->bip_bio;
496 int error = bip->bip_error;
497
498 if (bio_integrity_verify(bio)) {
499 clear_bit(BIO_UPTODATE, &bio->bi_flags);
500 error = -EIO;
501 }
502
503 /* Restore original bio completion handler */
504 bio->bi_end_io = bip->bip_end_io;
505
506 if (bio->bi_end_io)
507 bio->bi_end_io(bio, error);
508}
509
510/**
511 * bio_integrity_endio - Integrity I/O completion function
512 * @bio: Protected bio
513 * @error: Pointer to errno
514 *
515 * Description: Completion for integrity I/O
516 *
517 * Normally I/O completion is done in interrupt context. However,
518 * verifying I/O integrity is a time-consuming task which must be run
519 * in process context. This function postpones completion
520 * accordingly.
521 */
522void bio_integrity_endio(struct bio *bio, int error)
523{
524 struct bio_integrity_payload *bip = bio->bi_integrity;
525
526 BUG_ON(bip->bip_bio != bio);
527
528 bip->bip_error = error;
529 INIT_WORK(&bip->bip_work, bio_integrity_verify_fn);
530 queue_work(kintegrityd_wq, &bip->bip_work);
531}
532EXPORT_SYMBOL(bio_integrity_endio);
533
534/**
535 * bio_integrity_mark_head - Advance bip_vec skip bytes
536 * @bip: Integrity vector to advance
537 * @skip: Number of bytes to advance it
538 */
Jens Axboeb9846792008-06-17 19:05:48 +0200539void bio_integrity_mark_head(struct bio_integrity_payload *bip,
540 unsigned int skip)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200541{
542 struct bio_vec *iv;
543 unsigned int i;
544
545 bip_for_each_vec(iv, bip, i) {
546 if (skip == 0) {
547 bip->bip_idx = i;
548 return;
549 } else if (skip >= iv->bv_len) {
550 skip -= iv->bv_len;
551 } else { /* skip < iv->bv_len) */
552 iv->bv_offset += skip;
553 iv->bv_len -= skip;
554 bip->bip_idx = i;
555 return;
556 }
557 }
558}
559
560/**
561 * bio_integrity_mark_tail - Truncate bip_vec to be len bytes long
562 * @bip: Integrity vector to truncate
563 * @len: New length of integrity vector
564 */
Jens Axboeb9846792008-06-17 19:05:48 +0200565void bio_integrity_mark_tail(struct bio_integrity_payload *bip,
566 unsigned int len)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200567{
568 struct bio_vec *iv;
569 unsigned int i;
570
571 bip_for_each_vec(iv, bip, i) {
572 if (len == 0) {
573 bip->bip_vcnt = i;
574 return;
575 } else if (len >= iv->bv_len) {
576 len -= iv->bv_len;
577 } else { /* len < iv->bv_len) */
578 iv->bv_len = len;
579 len = 0;
580 }
581 }
582}
583
584/**
585 * bio_integrity_advance - Advance integrity vector
586 * @bio: bio whose integrity vector to update
587 * @bytes_done: number of data bytes that have been completed
588 *
589 * Description: This function calculates how many integrity bytes the
590 * number of completed data bytes correspond to and advances the
591 * integrity vector accordingly.
592 */
593void bio_integrity_advance(struct bio *bio, unsigned int bytes_done)
594{
595 struct bio_integrity_payload *bip = bio->bi_integrity;
596 struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
597 unsigned int nr_sectors;
598
599 BUG_ON(bip == NULL);
600 BUG_ON(bi == NULL);
601
602 nr_sectors = bio_integrity_hw_sectors(bi, bytes_done >> 9);
603 bio_integrity_mark_head(bip, nr_sectors * bi->tuple_size);
604}
605EXPORT_SYMBOL(bio_integrity_advance);
606
607/**
608 * bio_integrity_trim - Trim integrity vector
609 * @bio: bio whose integrity vector to update
610 * @offset: offset to first data sector
611 * @sectors: number of data sectors
612 *
613 * Description: Used to trim the integrity vector in a cloned bio.
614 * The ivec will be advanced corresponding to 'offset' data sectors
615 * and the length will be truncated corresponding to 'len' data
616 * sectors.
617 */
Jens Axboeb9846792008-06-17 19:05:48 +0200618void bio_integrity_trim(struct bio *bio, unsigned int offset,
619 unsigned int sectors)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200620{
621 struct bio_integrity_payload *bip = bio->bi_integrity;
622 struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
623 unsigned int nr_sectors;
624
625 BUG_ON(bip == NULL);
626 BUG_ON(bi == NULL);
627 BUG_ON(!bio_flagged(bio, BIO_CLONED));
628
629 nr_sectors = bio_integrity_hw_sectors(bi, sectors);
630 bip->bip_sector = bip->bip_sector + offset;
631 bio_integrity_mark_head(bip, offset * bi->tuple_size);
632 bio_integrity_mark_tail(bip, sectors * bi->tuple_size);
633}
634EXPORT_SYMBOL(bio_integrity_trim);
635
636/**
637 * bio_integrity_split - Split integrity metadata
638 * @bio: Protected bio
639 * @bp: Resulting bio_pair
640 * @sectors: Offset
641 *
642 * Description: Splits an integrity page into a bio_pair.
643 */
644void bio_integrity_split(struct bio *bio, struct bio_pair *bp, int sectors)
645{
646 struct blk_integrity *bi;
647 struct bio_integrity_payload *bip = bio->bi_integrity;
648 unsigned int nr_sectors;
649
650 if (bio_integrity(bio) == 0)
651 return;
652
653 bi = bdev_get_integrity(bio->bi_bdev);
654 BUG_ON(bi == NULL);
655 BUG_ON(bip->bip_vcnt != 1);
656
657 nr_sectors = bio_integrity_hw_sectors(bi, sectors);
658
659 bp->bio1.bi_integrity = &bp->bip1;
660 bp->bio2.bi_integrity = &bp->bip2;
661
662 bp->iv1 = bip->bip_vec[0];
663 bp->iv2 = bip->bip_vec[0];
664
665 bp->bip1.bip_vec = &bp->iv1;
666 bp->bip2.bip_vec = &bp->iv2;
667
668 bp->iv1.bv_len = sectors * bi->tuple_size;
669 bp->iv2.bv_offset += sectors * bi->tuple_size;
670 bp->iv2.bv_len -= sectors * bi->tuple_size;
671
672 bp->bip1.bip_sector = bio->bi_integrity->bip_sector;
673 bp->bip2.bip_sector = bio->bi_integrity->bip_sector + nr_sectors;
674
675 bp->bip1.bip_vcnt = bp->bip2.bip_vcnt = 1;
676 bp->bip1.bip_idx = bp->bip2.bip_idx = 0;
677}
678EXPORT_SYMBOL(bio_integrity_split);
679
680/**
681 * bio_integrity_clone - Callback for cloning bios with integrity metadata
682 * @bio: New bio
683 * @bio_src: Original bio
684 * @bs: bio_set to allocate bip from
685 *
686 * Description: Called to allocate a bip when cloning a bio
687 */
Jens Axboeb9846792008-06-17 19:05:48 +0200688int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
689 struct bio_set *bs)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200690{
691 struct bio_integrity_payload *bip_src = bio_src->bi_integrity;
692 struct bio_integrity_payload *bip;
693
694 BUG_ON(bip_src == NULL);
695
696 bip = bio_integrity_alloc_bioset(bio, GFP_NOIO, bip_src->bip_vcnt, bs);
697
698 if (bip == NULL)
699 return -EIO;
700
701 memcpy(bip->bip_vec, bip_src->bip_vec,
702 bip_src->bip_vcnt * sizeof(struct bio_vec));
703
704 bip->bip_sector = bip_src->bip_sector;
705 bip->bip_vcnt = bip_src->bip_vcnt;
706 bip->bip_idx = bip_src->bip_idx;
707
708 return 0;
709}
710EXPORT_SYMBOL(bio_integrity_clone);
711
712int bioset_integrity_create(struct bio_set *bs, int pool_size)
713{
714 bs->bio_integrity_pool = mempool_create_slab_pool(pool_size,
715 bio_integrity_slab);
716 if (!bs->bio_integrity_pool)
717 return -1;
718
719 return 0;
720}
721EXPORT_SYMBOL(bioset_integrity_create);
722
723void bioset_integrity_free(struct bio_set *bs)
724{
725 if (bs->bio_integrity_pool)
726 mempool_destroy(bs->bio_integrity_pool);
727}
728EXPORT_SYMBOL(bioset_integrity_free);
729
730void __init bio_integrity_init_slab(void)
731{
732 bio_integrity_slab = KMEM_CACHE(bio_integrity_payload,
733 SLAB_HWCACHE_ALIGN|SLAB_PANIC);
734}
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200735
736static int __init integrity_init(void)
737{
738 kintegrityd_wq = create_workqueue("kintegrityd");
739
740 if (!kintegrityd_wq)
741 panic("Failed to create kintegrityd\n");
742
743 return 0;
744}
745subsys_initcall(integrity_init);