blob: 612a5c38d3c1a5fc49e0d0990e19550c27217650 [file] [log] [blame]
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001/*
2 * bio-integrity.c - bio data integrity extensions
3 *
Martin K. Petersen7878cba2009-06-26 15:37:49 +02004 * Copyright (C) 2007, 2008, 2009 Oracle Corporation
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02005 * 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>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090027#include <linux/slab.h>
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +020028
Martin K. Petersen7878cba2009-06-26 15:37:49 +020029struct integrity_slab {
30 struct kmem_cache *slab;
31 unsigned short nr_vecs;
32 char name[8];
33};
34
35#define IS(x) { .nr_vecs = x, .name = "bip-"__stringify(x) }
36struct integrity_slab bip_slab[BIOVEC_NR_POOLS] __read_mostly = {
37 IS(1), IS(4), IS(16), IS(64), IS(128), IS(BIO_MAX_PAGES),
38};
39#undef IS
40
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +020041static struct workqueue_struct *kintegrityd_wq;
42
Martin K. Petersen7878cba2009-06-26 15:37:49 +020043static inline unsigned int vecs_to_idx(unsigned int nr)
44{
45 switch (nr) {
46 case 1:
47 return 0;
48 case 2 ... 4:
49 return 1;
50 case 5 ... 16:
51 return 2;
52 case 17 ... 64:
53 return 3;
54 case 65 ... 128:
55 return 4;
56 case 129 ... BIO_MAX_PAGES:
57 return 5;
58 default:
59 BUG();
60 }
61}
62
63static inline int use_bip_pool(unsigned int idx)
64{
Chuck Ebbert9e9432c2010-01-30 20:28:19 +010065 if (idx == BIOVEC_MAX_IDX)
Martin K. Petersen7878cba2009-06-26 15:37:49 +020066 return 1;
67
68 return 0;
69}
70
71/**
72 * bio_integrity_alloc_bioset - Allocate integrity payload and attach it to bio
73 * @bio: bio to attach integrity metadata to
74 * @gfp_mask: Memory allocation mask
75 * @nr_vecs: Number of integrity metadata scatter-gather elements
76 * @bs: bio_set to allocate from
77 *
78 * Description: This function prepares a bio for attaching integrity
79 * metadata. nr_vecs specifies the maximum number of pages containing
80 * integrity metadata that can be attached.
81 */
82struct bio_integrity_payload *bio_integrity_alloc_bioset(struct bio *bio,
83 gfp_t gfp_mask,
84 unsigned int nr_vecs,
85 struct bio_set *bs)
86{
87 struct bio_integrity_payload *bip;
88 unsigned int idx = vecs_to_idx(nr_vecs);
89
90 BUG_ON(bio == NULL);
91 bip = NULL;
92
93 /* Lower order allocations come straight from slab */
94 if (!use_bip_pool(idx))
95 bip = kmem_cache_alloc(bip_slab[idx].slab, gfp_mask);
96
97 /* Use mempool if lower order alloc failed or max vecs were requested */
98 if (bip == NULL) {
Chuck Ebbert9e9432c2010-01-30 20:28:19 +010099 idx = BIOVEC_MAX_IDX; /* so we free the payload properly later */
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200100 bip = mempool_alloc(bs->bio_integrity_pool, gfp_mask);
101
102 if (unlikely(bip == NULL)) {
103 printk(KERN_ERR "%s: could not alloc bip\n", __func__);
104 return NULL;
105 }
106 }
107
108 memset(bip, 0, sizeof(*bip));
109
110 bip->bip_slab = idx;
111 bip->bip_bio = bio;
112 bio->bi_integrity = bip;
113
114 return bip;
115}
116EXPORT_SYMBOL(bio_integrity_alloc_bioset);
117
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200118/**
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200119 * bio_integrity_alloc - Allocate integrity payload and attach it to bio
120 * @bio: bio to attach integrity metadata to
121 * @gfp_mask: Memory allocation mask
122 * @nr_vecs: Number of integrity metadata scatter-gather elements
123 *
124 * Description: This function prepares a bio for attaching integrity
125 * metadata. nr_vecs specifies the maximum number of pages containing
126 * integrity metadata that can be attached.
127 */
Jens Axboeb9846792008-06-17 19:05:48 +0200128struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio,
129 gfp_t gfp_mask,
130 unsigned int nr_vecs)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200131{
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200132 return bio_integrity_alloc_bioset(bio, gfp_mask, nr_vecs, fs_bio_set);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200133}
134EXPORT_SYMBOL(bio_integrity_alloc);
135
136/**
137 * bio_integrity_free - Free bio integrity payload
138 * @bio: bio containing bip to be freed
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200139 * @bs: bio_set this bio was allocated from
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200140 *
141 * Description: Used to free the integrity portion of a bio. Usually
142 * called from bio_free().
143 */
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200144void bio_integrity_free(struct bio *bio, struct bio_set *bs)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200145{
146 struct bio_integrity_payload *bip = bio->bi_integrity;
147
148 BUG_ON(bip == NULL);
149
150 /* A cloned bio doesn't own the integrity metadata */
Martin K. Petersen74aa8c22008-10-01 03:38:37 -0400151 if (!bio_flagged(bio, BIO_CLONED) && !bio_flagged(bio, BIO_FS_INTEGRITY)
152 && bip->bip_buf != NULL)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200153 kfree(bip->bip_buf);
154
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200155 if (use_bip_pool(bip->bip_slab))
156 mempool_free(bip, bs->bio_integrity_pool);
157 else
158 kmem_cache_free(bip_slab[bip->bip_slab].slab, bip);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200159
160 bio->bi_integrity = NULL;
161}
162EXPORT_SYMBOL(bio_integrity_free);
163
164/**
165 * bio_integrity_add_page - Attach integrity metadata
166 * @bio: bio to update
167 * @page: page containing integrity metadata
168 * @len: number of bytes of integrity metadata in page
169 * @offset: start offset within page
170 *
171 * Description: Attach a page containing integrity metadata to bio.
172 */
173int bio_integrity_add_page(struct bio *bio, struct page *page,
174 unsigned int len, unsigned int offset)
175{
176 struct bio_integrity_payload *bip = bio->bi_integrity;
177 struct bio_vec *iv;
178
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200179 if (bip->bip_vcnt >= bvec_nr_vecs(bip->bip_slab)) {
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200180 printk(KERN_ERR "%s: bip_vec full\n", __func__);
181 return 0;
182 }
183
184 iv = bip_vec_idx(bip, bip->bip_vcnt);
185 BUG_ON(iv == NULL);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200186
187 iv->bv_page = page;
188 iv->bv_len = len;
189 iv->bv_offset = offset;
190 bip->bip_vcnt++;
191
192 return len;
193}
194EXPORT_SYMBOL(bio_integrity_add_page);
195
Jens Axboe9c02f2b2008-09-18 09:31:53 -0700196static int bdev_integrity_enabled(struct block_device *bdev, int rw)
197{
198 struct blk_integrity *bi = bdev_get_integrity(bdev);
199
200 if (bi == NULL)
201 return 0;
202
203 if (rw == READ && bi->verify_fn != NULL &&
204 (bi->flags & INTEGRITY_FLAG_READ))
205 return 1;
206
207 if (rw == WRITE && bi->generate_fn != NULL &&
208 (bi->flags & INTEGRITY_FLAG_WRITE))
209 return 1;
210
211 return 0;
212}
213
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200214/**
215 * bio_integrity_enabled - Check whether integrity can be passed
216 * @bio: bio to check
217 *
218 * Description: Determines whether bio_integrity_prep() can be called
219 * on this bio or not. bio data direction and target device must be
220 * set prior to calling. The functions honors the write_generate and
221 * read_verify flags in sysfs.
222 */
223int bio_integrity_enabled(struct bio *bio)
224{
225 /* Already protected? */
226 if (bio_integrity(bio))
227 return 0;
228
229 return bdev_integrity_enabled(bio->bi_bdev, bio_data_dir(bio));
230}
231EXPORT_SYMBOL(bio_integrity_enabled);
232
233/**
234 * bio_integrity_hw_sectors - Convert 512b sectors to hardware ditto
235 * @bi: blk_integrity profile for device
236 * @sectors: Number of 512 sectors to convert
237 *
238 * Description: The block layer calculates everything in 512 byte
239 * sectors but integrity metadata is done in terms of the hardware
240 * sector size of the storage device. Convert the block layer sectors
241 * to physical sectors.
242 */
Jens Axboeb9846792008-06-17 19:05:48 +0200243static inline unsigned int bio_integrity_hw_sectors(struct blk_integrity *bi,
244 unsigned int sectors)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200245{
246 /* At this point there are only 512b or 4096b DIF/EPP devices */
247 if (bi->sector_size == 4096)
248 return sectors >>= 3;
249
250 return sectors;
251}
252
253/**
254 * bio_integrity_tag_size - Retrieve integrity tag space
255 * @bio: bio to inspect
256 *
257 * Description: Returns the maximum number of tag bytes that can be
258 * attached to this bio. Filesystems can use this to determine how
259 * much metadata to attach to an I/O.
260 */
261unsigned int bio_integrity_tag_size(struct bio *bio)
262{
263 struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
264
265 BUG_ON(bio->bi_size == 0);
266
267 return bi->tag_size * (bio->bi_size / bi->sector_size);
268}
269EXPORT_SYMBOL(bio_integrity_tag_size);
270
271int bio_integrity_tag(struct bio *bio, void *tag_buf, unsigned int len, int set)
272{
273 struct bio_integrity_payload *bip = bio->bi_integrity;
274 struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
275 unsigned int nr_sectors;
276
277 BUG_ON(bip->bip_buf == NULL);
278
279 if (bi->tag_size == 0)
280 return -1;
281
Jens Axboeb9846792008-06-17 19:05:48 +0200282 nr_sectors = bio_integrity_hw_sectors(bi,
283 DIV_ROUND_UP(len, bi->tag_size));
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200284
285 if (nr_sectors * bi->tuple_size > bip->bip_size) {
286 printk(KERN_ERR "%s: tag too big for bio: %u > %u\n",
287 __func__, nr_sectors * bi->tuple_size, bip->bip_size);
288 return -1;
289 }
290
291 if (set)
292 bi->set_tag_fn(bip->bip_buf, tag_buf, nr_sectors);
293 else
294 bi->get_tag_fn(bip->bip_buf, tag_buf, nr_sectors);
295
296 return 0;
297}
298
299/**
300 * bio_integrity_set_tag - Attach a tag buffer to a bio
301 * @bio: bio to attach buffer to
302 * @tag_buf: Pointer to a buffer containing tag data
303 * @len: Length of the included buffer
304 *
305 * Description: Use this function to tag a bio by leveraging the extra
306 * space provided by devices formatted with integrity protection. The
307 * size of the integrity buffer must be <= to the size reported by
308 * bio_integrity_tag_size().
309 */
310int bio_integrity_set_tag(struct bio *bio, void *tag_buf, unsigned int len)
311{
312 BUG_ON(bio_data_dir(bio) != WRITE);
313
314 return bio_integrity_tag(bio, tag_buf, len, 1);
315}
316EXPORT_SYMBOL(bio_integrity_set_tag);
317
318/**
319 * bio_integrity_get_tag - Retrieve a tag buffer from a bio
320 * @bio: bio to retrieve buffer from
321 * @tag_buf: Pointer to a buffer for the tag data
322 * @len: Length of the target buffer
323 *
324 * Description: Use this function to retrieve the tag buffer from a
325 * completed I/O. The size of the integrity buffer must be <= to the
326 * size reported by bio_integrity_tag_size().
327 */
328int bio_integrity_get_tag(struct bio *bio, void *tag_buf, unsigned int len)
329{
330 BUG_ON(bio_data_dir(bio) != READ);
331
332 return bio_integrity_tag(bio, tag_buf, len, 0);
333}
334EXPORT_SYMBOL(bio_integrity_get_tag);
335
336/**
337 * bio_integrity_generate - Generate integrity metadata for a bio
338 * @bio: bio to generate integrity metadata for
339 *
340 * Description: Generates integrity metadata for a bio by calling the
341 * block device's generation callback function. The bio must have a
342 * bip attached with enough room to accommodate the generated
343 * integrity metadata.
344 */
345static void bio_integrity_generate(struct bio *bio)
346{
347 struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
348 struct blk_integrity_exchg bix;
349 struct bio_vec *bv;
350 sector_t sector = bio->bi_sector;
351 unsigned int i, sectors, total;
352 void *prot_buf = bio->bi_integrity->bip_buf;
353
354 total = 0;
355 bix.disk_name = bio->bi_bdev->bd_disk->disk_name;
356 bix.sector_size = bi->sector_size;
357
358 bio_for_each_segment(bv, bio, i) {
359 void *kaddr = kmap_atomic(bv->bv_page, KM_USER0);
360 bix.data_buf = kaddr + bv->bv_offset;
361 bix.data_size = bv->bv_len;
362 bix.prot_buf = prot_buf;
363 bix.sector = sector;
364
365 bi->generate_fn(&bix);
366
367 sectors = bv->bv_len / bi->sector_size;
368 sector += sectors;
369 prot_buf += sectors * bi->tuple_size;
370 total += sectors * bi->tuple_size;
371 BUG_ON(total > bio->bi_integrity->bip_size);
372
373 kunmap_atomic(kaddr, KM_USER0);
374 }
375}
376
Jens Axboe9c02f2b2008-09-18 09:31:53 -0700377static inline unsigned short blk_integrity_tuple_size(struct blk_integrity *bi)
378{
379 if (bi)
380 return bi->tuple_size;
381
382 return 0;
383}
384
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200385/**
386 * bio_integrity_prep - Prepare bio for integrity I/O
387 * @bio: bio to prepare
388 *
389 * Description: Allocates a buffer for integrity metadata, maps the
390 * pages and attaches them to a bio. The bio must have data
391 * direction, target device and start sector set priot to calling. In
392 * the WRITE case, integrity metadata will be generated using the
393 * block device's integrity function. In the READ case, the buffer
394 * will be prepared for DMA and a suitable end_io handler set up.
395 */
396int bio_integrity_prep(struct bio *bio)
397{
398 struct bio_integrity_payload *bip;
399 struct blk_integrity *bi;
400 struct request_queue *q;
401 void *buf;
402 unsigned long start, end;
403 unsigned int len, nr_pages;
404 unsigned int bytes, offset, i;
405 unsigned int sectors;
406
407 bi = bdev_get_integrity(bio->bi_bdev);
408 q = bdev_get_queue(bio->bi_bdev);
409 BUG_ON(bi == NULL);
410 BUG_ON(bio_integrity(bio));
411
412 sectors = bio_integrity_hw_sectors(bi, bio_sectors(bio));
413
414 /* Allocate kernel buffer for protection data */
415 len = sectors * blk_integrity_tuple_size(bi);
416 buf = kmalloc(len, GFP_NOIO | __GFP_NOFAIL | q->bounce_gfp);
417 if (unlikely(buf == NULL)) {
418 printk(KERN_ERR "could not allocate integrity buffer\n");
419 return -EIO;
420 }
421
422 end = (((unsigned long) buf) + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
423 start = ((unsigned long) buf) >> PAGE_SHIFT;
424 nr_pages = end - start;
425
426 /* Allocate bio integrity payload and integrity vectors */
427 bip = bio_integrity_alloc(bio, GFP_NOIO, nr_pages);
428 if (unlikely(bip == NULL)) {
429 printk(KERN_ERR "could not allocate data integrity bioset\n");
430 kfree(buf);
431 return -EIO;
432 }
433
434 bip->bip_buf = buf;
435 bip->bip_size = len;
436 bip->bip_sector = bio->bi_sector;
437
438 /* Map it */
439 offset = offset_in_page(buf);
440 for (i = 0 ; i < nr_pages ; i++) {
441 int ret;
442 bytes = PAGE_SIZE - offset;
443
444 if (len <= 0)
445 break;
446
447 if (bytes > len)
448 bytes = len;
449
450 ret = bio_integrity_add_page(bio, virt_to_page(buf),
451 bytes, offset);
452
453 if (ret == 0)
454 return 0;
455
456 if (ret < bytes)
457 break;
458
459 buf += bytes;
460 len -= bytes;
461 offset = 0;
462 }
463
464 /* Install custom I/O completion handler if read verify is enabled */
465 if (bio_data_dir(bio) == READ) {
466 bip->bip_end_io = bio->bi_end_io;
467 bio->bi_end_io = bio_integrity_endio;
468 }
469
470 /* Auto-generate integrity metadata if this is a write */
471 if (bio_data_dir(bio) == WRITE)
472 bio_integrity_generate(bio);
473
474 return 0;
475}
476EXPORT_SYMBOL(bio_integrity_prep);
477
478/**
479 * bio_integrity_verify - Verify integrity metadata for a bio
480 * @bio: bio to verify
481 *
482 * Description: This function is called to verify the integrity of a
483 * bio. The data in the bio io_vec is compared to the integrity
484 * metadata returned by the HBA.
485 */
486static int bio_integrity_verify(struct bio *bio)
487{
488 struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
489 struct blk_integrity_exchg bix;
490 struct bio_vec *bv;
491 sector_t sector = bio->bi_integrity->bip_sector;
492 unsigned int i, sectors, total, ret;
493 void *prot_buf = bio->bi_integrity->bip_buf;
494
495 ret = total = 0;
496 bix.disk_name = bio->bi_bdev->bd_disk->disk_name;
497 bix.sector_size = bi->sector_size;
498
499 bio_for_each_segment(bv, bio, i) {
500 void *kaddr = kmap_atomic(bv->bv_page, KM_USER0);
501 bix.data_buf = kaddr + bv->bv_offset;
502 bix.data_size = bv->bv_len;
503 bix.prot_buf = prot_buf;
504 bix.sector = sector;
505
506 ret = bi->verify_fn(&bix);
507
508 if (ret) {
509 kunmap_atomic(kaddr, KM_USER0);
Martin K. Petersen7b24fc42009-01-04 02:43:38 -0500510 return ret;
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200511 }
512
513 sectors = bv->bv_len / bi->sector_size;
514 sector += sectors;
515 prot_buf += sectors * bi->tuple_size;
516 total += sectors * bi->tuple_size;
517 BUG_ON(total > bio->bi_integrity->bip_size);
518
519 kunmap_atomic(kaddr, KM_USER0);
520 }
521
522 return ret;
523}
524
525/**
526 * bio_integrity_verify_fn - Integrity I/O completion worker
527 * @work: Work struct stored in bio to be verified
528 *
529 * Description: This workqueue function is called to complete a READ
530 * request. The function verifies the transferred integrity metadata
531 * and then calls the original bio end_io function.
532 */
533static void bio_integrity_verify_fn(struct work_struct *work)
534{
Jens Axboeb9846792008-06-17 19:05:48 +0200535 struct bio_integrity_payload *bip =
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200536 container_of(work, struct bio_integrity_payload, bip_work);
537 struct bio *bio = bip->bip_bio;
Martin K. Petersen7b24fc42009-01-04 02:43:38 -0500538 int error;
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200539
Martin K. Petersen7b24fc42009-01-04 02:43:38 -0500540 error = bio_integrity_verify(bio);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200541
542 /* Restore original bio completion handler */
543 bio->bi_end_io = bip->bip_end_io;
Martin K. Petersen7b24fc42009-01-04 02:43:38 -0500544 bio_endio(bio, error);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200545}
546
547/**
548 * bio_integrity_endio - Integrity I/O completion function
549 * @bio: Protected bio
550 * @error: Pointer to errno
551 *
552 * Description: Completion for integrity I/O
553 *
554 * Normally I/O completion is done in interrupt context. However,
555 * verifying I/O integrity is a time-consuming task which must be run
556 * in process context. This function postpones completion
557 * accordingly.
558 */
559void bio_integrity_endio(struct bio *bio, int error)
560{
561 struct bio_integrity_payload *bip = bio->bi_integrity;
562
563 BUG_ON(bip->bip_bio != bio);
564
Martin K. Petersen7b24fc42009-01-04 02:43:38 -0500565 /* In case of an I/O error there is no point in verifying the
566 * integrity metadata. Restore original bio end_io handler
567 * and run it.
568 */
569 if (error) {
570 bio->bi_end_io = bip->bip_end_io;
571 bio_endio(bio, error);
572
573 return;
574 }
575
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200576 INIT_WORK(&bip->bip_work, bio_integrity_verify_fn);
577 queue_work(kintegrityd_wq, &bip->bip_work);
578}
579EXPORT_SYMBOL(bio_integrity_endio);
580
581/**
582 * bio_integrity_mark_head - Advance bip_vec skip bytes
583 * @bip: Integrity vector to advance
584 * @skip: Number of bytes to advance it
585 */
Jens Axboeb9846792008-06-17 19:05:48 +0200586void bio_integrity_mark_head(struct bio_integrity_payload *bip,
587 unsigned int skip)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200588{
589 struct bio_vec *iv;
590 unsigned int i;
591
592 bip_for_each_vec(iv, bip, i) {
593 if (skip == 0) {
594 bip->bip_idx = i;
595 return;
596 } else if (skip >= iv->bv_len) {
597 skip -= iv->bv_len;
598 } else { /* skip < iv->bv_len) */
599 iv->bv_offset += skip;
600 iv->bv_len -= skip;
601 bip->bip_idx = i;
602 return;
603 }
604 }
605}
606
607/**
608 * bio_integrity_mark_tail - Truncate bip_vec to be len bytes long
609 * @bip: Integrity vector to truncate
610 * @len: New length of integrity vector
611 */
Jens Axboeb9846792008-06-17 19:05:48 +0200612void bio_integrity_mark_tail(struct bio_integrity_payload *bip,
613 unsigned int len)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200614{
615 struct bio_vec *iv;
616 unsigned int i;
617
618 bip_for_each_vec(iv, bip, i) {
619 if (len == 0) {
620 bip->bip_vcnt = i;
621 return;
622 } else if (len >= iv->bv_len) {
623 len -= iv->bv_len;
624 } else { /* len < iv->bv_len) */
625 iv->bv_len = len;
626 len = 0;
627 }
628 }
629}
630
631/**
632 * bio_integrity_advance - Advance integrity vector
633 * @bio: bio whose integrity vector to update
634 * @bytes_done: number of data bytes that have been completed
635 *
636 * Description: This function calculates how many integrity bytes the
637 * number of completed data bytes correspond to and advances the
638 * integrity vector accordingly.
639 */
640void bio_integrity_advance(struct bio *bio, unsigned int bytes_done)
641{
642 struct bio_integrity_payload *bip = bio->bi_integrity;
643 struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
644 unsigned int nr_sectors;
645
646 BUG_ON(bip == NULL);
647 BUG_ON(bi == NULL);
648
649 nr_sectors = bio_integrity_hw_sectors(bi, bytes_done >> 9);
650 bio_integrity_mark_head(bip, nr_sectors * bi->tuple_size);
651}
652EXPORT_SYMBOL(bio_integrity_advance);
653
654/**
655 * bio_integrity_trim - Trim integrity vector
656 * @bio: bio whose integrity vector to update
657 * @offset: offset to first data sector
658 * @sectors: number of data sectors
659 *
660 * Description: Used to trim the integrity vector in a cloned bio.
661 * The ivec will be advanced corresponding to 'offset' data sectors
662 * and the length will be truncated corresponding to 'len' data
663 * sectors.
664 */
Jens Axboeb9846792008-06-17 19:05:48 +0200665void bio_integrity_trim(struct bio *bio, unsigned int offset,
666 unsigned int sectors)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200667{
668 struct bio_integrity_payload *bip = bio->bi_integrity;
669 struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
670 unsigned int nr_sectors;
671
672 BUG_ON(bip == NULL);
673 BUG_ON(bi == NULL);
674 BUG_ON(!bio_flagged(bio, BIO_CLONED));
675
676 nr_sectors = bio_integrity_hw_sectors(bi, sectors);
677 bip->bip_sector = bip->bip_sector + offset;
678 bio_integrity_mark_head(bip, offset * bi->tuple_size);
679 bio_integrity_mark_tail(bip, sectors * bi->tuple_size);
680}
681EXPORT_SYMBOL(bio_integrity_trim);
682
683/**
684 * bio_integrity_split - Split integrity metadata
685 * @bio: Protected bio
686 * @bp: Resulting bio_pair
687 * @sectors: Offset
688 *
689 * Description: Splits an integrity page into a bio_pair.
690 */
691void bio_integrity_split(struct bio *bio, struct bio_pair *bp, int sectors)
692{
693 struct blk_integrity *bi;
694 struct bio_integrity_payload *bip = bio->bi_integrity;
695 unsigned int nr_sectors;
696
697 if (bio_integrity(bio) == 0)
698 return;
699
700 bi = bdev_get_integrity(bio->bi_bdev);
701 BUG_ON(bi == NULL);
702 BUG_ON(bip->bip_vcnt != 1);
703
704 nr_sectors = bio_integrity_hw_sectors(bi, sectors);
705
706 bp->bio1.bi_integrity = &bp->bip1;
707 bp->bio2.bi_integrity = &bp->bip2;
708
709 bp->iv1 = bip->bip_vec[0];
710 bp->iv2 = bip->bip_vec[0];
711
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200712 bp->bip1.bip_vec[0] = bp->iv1;
713 bp->bip2.bip_vec[0] = bp->iv2;
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200714
715 bp->iv1.bv_len = sectors * bi->tuple_size;
716 bp->iv2.bv_offset += sectors * bi->tuple_size;
717 bp->iv2.bv_len -= sectors * bi->tuple_size;
718
719 bp->bip1.bip_sector = bio->bi_integrity->bip_sector;
720 bp->bip2.bip_sector = bio->bi_integrity->bip_sector + nr_sectors;
721
722 bp->bip1.bip_vcnt = bp->bip2.bip_vcnt = 1;
723 bp->bip1.bip_idx = bp->bip2.bip_idx = 0;
724}
725EXPORT_SYMBOL(bio_integrity_split);
726
727/**
728 * bio_integrity_clone - Callback for cloning bios with integrity metadata
729 * @bio: New bio
730 * @bio_src: Original bio
un'ichi Nomura87092692009-03-09 10:40:52 +0100731 * @gfp_mask: Memory allocation mask
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200732 * @bs: bio_set to allocate bip from
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200733 *
734 * Description: Called to allocate a bip when cloning a bio
735 */
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200736int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
737 gfp_t gfp_mask, struct bio_set *bs)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200738{
739 struct bio_integrity_payload *bip_src = bio_src->bi_integrity;
740 struct bio_integrity_payload *bip;
741
742 BUG_ON(bip_src == NULL);
743
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200744 bip = bio_integrity_alloc_bioset(bio, gfp_mask, bip_src->bip_vcnt, bs);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200745
746 if (bip == NULL)
747 return -EIO;
748
749 memcpy(bip->bip_vec, bip_src->bip_vec,
750 bip_src->bip_vcnt * sizeof(struct bio_vec));
751
752 bip->bip_sector = bip_src->bip_sector;
753 bip->bip_vcnt = bip_src->bip_vcnt;
754 bip->bip_idx = bip_src->bip_idx;
755
756 return 0;
757}
758EXPORT_SYMBOL(bio_integrity_clone);
759
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200760int bioset_integrity_create(struct bio_set *bs, int pool_size)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200761{
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200762 unsigned int max_slab = vecs_to_idx(BIO_MAX_PAGES);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200763
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200764 bs->bio_integrity_pool =
765 mempool_create_slab_pool(pool_size, bip_slab[max_slab].slab);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200766
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200767 if (!bs->bio_integrity_pool)
768 return -1;
Martin K. Petersen6d2a78e2009-03-10 08:27:39 +0100769
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200770 return 0;
771}
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200772EXPORT_SYMBOL(bioset_integrity_create);
773
774void bioset_integrity_free(struct bio_set *bs)
775{
776 if (bs->bio_integrity_pool)
777 mempool_destroy(bs->bio_integrity_pool);
778}
779EXPORT_SYMBOL(bioset_integrity_free);
780
781void __init bio_integrity_init(void)
782{
783 unsigned int i;
784
785 kintegrityd_wq = create_workqueue("kintegrityd");
786 if (!kintegrityd_wq)
787 panic("Failed to create kintegrityd\n");
788
789 for (i = 0 ; i < BIOVEC_NR_POOLS ; i++) {
790 unsigned int size;
791
792 size = sizeof(struct bio_integrity_payload)
793 + bip_slab[i].nr_vecs * sizeof(struct bio_vec);
794
795 bip_slab[i].slab =
796 kmem_cache_create(bip_slab[i].name, size, 0,
797 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
798 }
799}