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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>
Paul Gortmakerafeacc82011-05-26 16:00:52 -040025#include <linux/export.h>
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +020026#include <linux/bio.h>
27#include <linux/workqueue.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090028#include <linux/slab.h>
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +020029
Kent Overstreet9f060e22012-10-12 15:29:33 -070030#define BIP_INLINE_VECS 4
Martin K. Petersen7878cba2009-06-26 15:37:49 +020031
Kent Overstreet9f060e22012-10-12 15:29:33 -070032static struct kmem_cache *bip_slab;
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +020033static struct workqueue_struct *kintegrityd_wq;
34
Martin K. Petersen7878cba2009-06-26 15:37:49 +020035/**
Kent Overstreet1e2a410f2012-09-06 15:34:56 -070036 * bio_integrity_alloc - Allocate integrity payload and attach it to bio
Martin K. Petersen7878cba2009-06-26 15:37:49 +020037 * @bio: bio to attach integrity metadata to
38 * @gfp_mask: Memory allocation mask
39 * @nr_vecs: Number of integrity metadata scatter-gather elements
Martin K. Petersen7878cba2009-06-26 15:37:49 +020040 *
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 */
Kent Overstreet1e2a410f2012-09-06 15:34:56 -070045struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio,
46 gfp_t gfp_mask,
47 unsigned int nr_vecs)
Martin K. Petersen7878cba2009-06-26 15:37:49 +020048{
49 struct bio_integrity_payload *bip;
Kent Overstreet1e2a410f2012-09-06 15:34:56 -070050 struct bio_set *bs = bio->bi_pool;
Kent Overstreet9f060e22012-10-12 15:29:33 -070051 unsigned long idx = BIO_POOL_NONE;
52 unsigned inline_vecs;
Kent Overstreet1e2a410f2012-09-06 15:34:56 -070053
Kent Overstreet9f060e22012-10-12 15:29:33 -070054 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 {
Martin K. Petersen7878cba2009-06-26 15:37:49 +020059 bip = mempool_alloc(bs->bio_integrity_pool, gfp_mask);
Kent Overstreet9f060e22012-10-12 15:29:33 -070060 inline_vecs = BIP_INLINE_VECS;
Martin K. Petersen7878cba2009-06-26 15:37:49 +020061 }
62
Kent Overstreet9f060e22012-10-12 15:29:33 -070063 if (unlikely(!bip))
64 return NULL;
65
Martin K. Petersen7878cba2009-06-26 15:37:49 +020066 memset(bip, 0, sizeof(*bip));
67
Kent Overstreet9f060e22012-10-12 15:29:33 -070068 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
Martin K. Petersen7878cba2009-06-26 15:37:49 +020077 bip->bip_slab = idx;
78 bip->bip_bio = bio;
79 bio->bi_integrity = bip;
80
81 return bip;
Kent Overstreet9f060e22012-10-12 15:29:33 -070082err:
83 mempool_free(bip, bs->bio_integrity_pool);
84 return NULL;
Martin K. Petersen7878cba2009-06-26 15:37:49 +020085}
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +020086EXPORT_SYMBOL(bio_integrity_alloc);
87
88/**
89 * bio_integrity_free - Free bio integrity payload
90 * @bio: bio containing bip to be freed
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +020091 *
92 * Description: Used to free the integrity portion of a bio. Usually
93 * called from bio_free().
94 */
Kent Overstreet1e2a410f2012-09-06 15:34:56 -070095void bio_integrity_free(struct bio *bio)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +020096{
97 struct bio_integrity_payload *bip = bio->bi_integrity;
Kent Overstreet1e2a410f2012-09-06 15:34:56 -070098 struct bio_set *bs = bio->bi_pool;
99
Kent Overstreet29ed7812012-09-04 09:54:22 -0700100 if (bip->bip_owns_buf)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200101 kfree(bip->bip_buf);
102
Kent Overstreet9f060e22012-10-12 15:29:33 -0700103 if (bs) {
104 if (bip->bip_slab != BIO_POOL_NONE)
105 bvec_free(bs->bvec_integrity_pool, bip->bip_vec,
106 bip->bip_slab);
107
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200108 mempool_free(bip, bs->bio_integrity_pool);
Kent Overstreet9f060e22012-10-12 15:29:33 -0700109 } else {
110 kfree(bip);
111 }
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200112
113 bio->bi_integrity = NULL;
114}
115EXPORT_SYMBOL(bio_integrity_free);
116
117/**
118 * bio_integrity_add_page - Attach integrity metadata
119 * @bio: bio to update
120 * @page: page containing integrity metadata
121 * @len: number of bytes of integrity metadata in page
122 * @offset: start offset within page
123 *
124 * Description: Attach a page containing integrity metadata to bio.
125 */
126int bio_integrity_add_page(struct bio *bio, struct page *page,
127 unsigned int len, unsigned int offset)
128{
129 struct bio_integrity_payload *bip = bio->bi_integrity;
130 struct bio_vec *iv;
131
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200132 if (bip->bip_vcnt >= bvec_nr_vecs(bip->bip_slab)) {
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200133 printk(KERN_ERR "%s: bip_vec full\n", __func__);
134 return 0;
135 }
136
137 iv = bip_vec_idx(bip, bip->bip_vcnt);
138 BUG_ON(iv == NULL);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200139
140 iv->bv_page = page;
141 iv->bv_len = len;
142 iv->bv_offset = offset;
143 bip->bip_vcnt++;
144
145 return len;
146}
147EXPORT_SYMBOL(bio_integrity_add_page);
148
Jens Axboe9c02f2b2008-09-18 09:31:53 -0700149static int bdev_integrity_enabled(struct block_device *bdev, int rw)
150{
151 struct blk_integrity *bi = bdev_get_integrity(bdev);
152
153 if (bi == NULL)
154 return 0;
155
156 if (rw == READ && bi->verify_fn != NULL &&
157 (bi->flags & INTEGRITY_FLAG_READ))
158 return 1;
159
160 if (rw == WRITE && bi->generate_fn != NULL &&
161 (bi->flags & INTEGRITY_FLAG_WRITE))
162 return 1;
163
164 return 0;
165}
166
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200167/**
168 * bio_integrity_enabled - Check whether integrity can be passed
169 * @bio: bio to check
170 *
171 * Description: Determines whether bio_integrity_prep() can be called
172 * on this bio or not. bio data direction and target device must be
173 * set prior to calling. The functions honors the write_generate and
174 * read_verify flags in sysfs.
175 */
176int bio_integrity_enabled(struct bio *bio)
177{
178 /* Already protected? */
179 if (bio_integrity(bio))
180 return 0;
181
182 return bdev_integrity_enabled(bio->bi_bdev, bio_data_dir(bio));
183}
184EXPORT_SYMBOL(bio_integrity_enabled);
185
186/**
187 * bio_integrity_hw_sectors - Convert 512b sectors to hardware ditto
188 * @bi: blk_integrity profile for device
189 * @sectors: Number of 512 sectors to convert
190 *
191 * Description: The block layer calculates everything in 512 byte
192 * sectors but integrity metadata is done in terms of the hardware
193 * sector size of the storage device. Convert the block layer sectors
194 * to physical sectors.
195 */
Jens Axboeb9846792008-06-17 19:05:48 +0200196static inline unsigned int bio_integrity_hw_sectors(struct blk_integrity *bi,
197 unsigned int sectors)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200198{
199 /* At this point there are only 512b or 4096b DIF/EPP devices */
200 if (bi->sector_size == 4096)
201 return sectors >>= 3;
202
203 return sectors;
204}
205
206/**
207 * bio_integrity_tag_size - Retrieve integrity tag space
208 * @bio: bio to inspect
209 *
210 * Description: Returns the maximum number of tag bytes that can be
211 * attached to this bio. Filesystems can use this to determine how
212 * much metadata to attach to an I/O.
213 */
214unsigned int bio_integrity_tag_size(struct bio *bio)
215{
216 struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
217
218 BUG_ON(bio->bi_size == 0);
219
220 return bi->tag_size * (bio->bi_size / bi->sector_size);
221}
222EXPORT_SYMBOL(bio_integrity_tag_size);
223
224int bio_integrity_tag(struct bio *bio, void *tag_buf, unsigned int len, int set)
225{
226 struct bio_integrity_payload *bip = bio->bi_integrity;
227 struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
228 unsigned int nr_sectors;
229
230 BUG_ON(bip->bip_buf == NULL);
231
232 if (bi->tag_size == 0)
233 return -1;
234
Jens Axboeb9846792008-06-17 19:05:48 +0200235 nr_sectors = bio_integrity_hw_sectors(bi,
236 DIV_ROUND_UP(len, bi->tag_size));
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200237
238 if (nr_sectors * bi->tuple_size > bip->bip_size) {
239 printk(KERN_ERR "%s: tag too big for bio: %u > %u\n",
240 __func__, nr_sectors * bi->tuple_size, bip->bip_size);
241 return -1;
242 }
243
244 if (set)
245 bi->set_tag_fn(bip->bip_buf, tag_buf, nr_sectors);
246 else
247 bi->get_tag_fn(bip->bip_buf, tag_buf, nr_sectors);
248
249 return 0;
250}
251
252/**
253 * bio_integrity_set_tag - Attach a tag buffer to a bio
254 * @bio: bio to attach buffer to
255 * @tag_buf: Pointer to a buffer containing tag data
256 * @len: Length of the included buffer
257 *
258 * Description: Use this function to tag a bio by leveraging the extra
259 * space provided by devices formatted with integrity protection. The
260 * size of the integrity buffer must be <= to the size reported by
261 * bio_integrity_tag_size().
262 */
263int bio_integrity_set_tag(struct bio *bio, void *tag_buf, unsigned int len)
264{
265 BUG_ON(bio_data_dir(bio) != WRITE);
266
267 return bio_integrity_tag(bio, tag_buf, len, 1);
268}
269EXPORT_SYMBOL(bio_integrity_set_tag);
270
271/**
272 * bio_integrity_get_tag - Retrieve a tag buffer from a bio
273 * @bio: bio to retrieve buffer from
274 * @tag_buf: Pointer to a buffer for the tag data
275 * @len: Length of the target buffer
276 *
277 * Description: Use this function to retrieve the tag buffer from a
278 * completed I/O. The size of the integrity buffer must be <= to the
279 * size reported by bio_integrity_tag_size().
280 */
281int bio_integrity_get_tag(struct bio *bio, void *tag_buf, unsigned int len)
282{
283 BUG_ON(bio_data_dir(bio) != READ);
284
285 return bio_integrity_tag(bio, tag_buf, len, 0);
286}
287EXPORT_SYMBOL(bio_integrity_get_tag);
288
289/**
290 * bio_integrity_generate - Generate integrity metadata for a bio
291 * @bio: bio to generate integrity metadata for
292 *
293 * Description: Generates integrity metadata for a bio by calling the
294 * block device's generation callback function. The bio must have a
295 * bip attached with enough room to accommodate the generated
296 * integrity metadata.
297 */
298static void bio_integrity_generate(struct bio *bio)
299{
300 struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
301 struct blk_integrity_exchg bix;
302 struct bio_vec *bv;
303 sector_t sector = bio->bi_sector;
304 unsigned int i, sectors, total;
305 void *prot_buf = bio->bi_integrity->bip_buf;
306
307 total = 0;
308 bix.disk_name = bio->bi_bdev->bd_disk->disk_name;
309 bix.sector_size = bi->sector_size;
310
311 bio_for_each_segment(bv, bio, i) {
Cong Wange8e3c3d2011-11-25 23:14:27 +0800312 void *kaddr = kmap_atomic(bv->bv_page);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200313 bix.data_buf = kaddr + bv->bv_offset;
314 bix.data_size = bv->bv_len;
315 bix.prot_buf = prot_buf;
316 bix.sector = sector;
317
318 bi->generate_fn(&bix);
319
320 sectors = bv->bv_len / bi->sector_size;
321 sector += sectors;
322 prot_buf += sectors * bi->tuple_size;
323 total += sectors * bi->tuple_size;
324 BUG_ON(total > bio->bi_integrity->bip_size);
325
Cong Wange8e3c3d2011-11-25 23:14:27 +0800326 kunmap_atomic(kaddr);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200327 }
328}
329
Jens Axboe9c02f2b2008-09-18 09:31:53 -0700330static inline unsigned short blk_integrity_tuple_size(struct blk_integrity *bi)
331{
332 if (bi)
333 return bi->tuple_size;
334
335 return 0;
336}
337
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200338/**
339 * bio_integrity_prep - Prepare bio for integrity I/O
340 * @bio: bio to prepare
341 *
342 * Description: Allocates a buffer for integrity metadata, maps the
343 * pages and attaches them to a bio. The bio must have data
344 * direction, target device and start sector set priot to calling. In
345 * the WRITE case, integrity metadata will be generated using the
346 * block device's integrity function. In the READ case, the buffer
347 * will be prepared for DMA and a suitable end_io handler set up.
348 */
349int bio_integrity_prep(struct bio *bio)
350{
351 struct bio_integrity_payload *bip;
352 struct blk_integrity *bi;
353 struct request_queue *q;
354 void *buf;
355 unsigned long start, end;
356 unsigned int len, nr_pages;
357 unsigned int bytes, offset, i;
358 unsigned int sectors;
359
360 bi = bdev_get_integrity(bio->bi_bdev);
361 q = bdev_get_queue(bio->bi_bdev);
362 BUG_ON(bi == NULL);
363 BUG_ON(bio_integrity(bio));
364
365 sectors = bio_integrity_hw_sectors(bi, bio_sectors(bio));
366
367 /* Allocate kernel buffer for protection data */
368 len = sectors * blk_integrity_tuple_size(bi);
David Rientjes72f46502010-08-23 13:35:09 +0200369 buf = kmalloc(len, GFP_NOIO | q->bounce_gfp);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200370 if (unlikely(buf == NULL)) {
371 printk(KERN_ERR "could not allocate integrity buffer\n");
Andrew Morton220eb7f2010-08-23 13:36:20 +0200372 return -ENOMEM;
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200373 }
374
375 end = (((unsigned long) buf) + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
376 start = ((unsigned long) buf) >> PAGE_SHIFT;
377 nr_pages = end - start;
378
379 /* Allocate bio integrity payload and integrity vectors */
380 bip = bio_integrity_alloc(bio, GFP_NOIO, nr_pages);
381 if (unlikely(bip == NULL)) {
382 printk(KERN_ERR "could not allocate data integrity bioset\n");
383 kfree(buf);
384 return -EIO;
385 }
386
Kent Overstreet29ed7812012-09-04 09:54:22 -0700387 bip->bip_owns_buf = 1;
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200388 bip->bip_buf = buf;
389 bip->bip_size = len;
390 bip->bip_sector = bio->bi_sector;
391
392 /* Map it */
393 offset = offset_in_page(buf);
394 for (i = 0 ; i < nr_pages ; i++) {
395 int ret;
396 bytes = PAGE_SIZE - offset;
397
398 if (len <= 0)
399 break;
400
401 if (bytes > len)
402 bytes = len;
403
404 ret = bio_integrity_add_page(bio, virt_to_page(buf),
405 bytes, offset);
406
407 if (ret == 0)
408 return 0;
409
410 if (ret < bytes)
411 break;
412
413 buf += bytes;
414 len -= bytes;
415 offset = 0;
416 }
417
418 /* Install custom I/O completion handler if read verify is enabled */
419 if (bio_data_dir(bio) == READ) {
420 bip->bip_end_io = bio->bi_end_io;
421 bio->bi_end_io = bio_integrity_endio;
422 }
423
424 /* Auto-generate integrity metadata if this is a write */
425 if (bio_data_dir(bio) == WRITE)
426 bio_integrity_generate(bio);
427
428 return 0;
429}
430EXPORT_SYMBOL(bio_integrity_prep);
431
432/**
433 * bio_integrity_verify - Verify integrity metadata for a bio
434 * @bio: bio to verify
435 *
436 * Description: This function is called to verify the integrity of a
437 * bio. The data in the bio io_vec is compared to the integrity
438 * metadata returned by the HBA.
439 */
440static int bio_integrity_verify(struct bio *bio)
441{
442 struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
443 struct blk_integrity_exchg bix;
444 struct bio_vec *bv;
445 sector_t sector = bio->bi_integrity->bip_sector;
446 unsigned int i, sectors, total, ret;
447 void *prot_buf = bio->bi_integrity->bip_buf;
448
449 ret = total = 0;
450 bix.disk_name = bio->bi_bdev->bd_disk->disk_name;
451 bix.sector_size = bi->sector_size;
452
453 bio_for_each_segment(bv, bio, i) {
Cong Wange8e3c3d2011-11-25 23:14:27 +0800454 void *kaddr = kmap_atomic(bv->bv_page);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200455 bix.data_buf = kaddr + bv->bv_offset;
456 bix.data_size = bv->bv_len;
457 bix.prot_buf = prot_buf;
458 bix.sector = sector;
459
460 ret = bi->verify_fn(&bix);
461
462 if (ret) {
Cong Wange8e3c3d2011-11-25 23:14:27 +0800463 kunmap_atomic(kaddr);
Martin K. Petersen7b24fc42009-01-04 02:43:38 -0500464 return ret;
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200465 }
466
467 sectors = bv->bv_len / bi->sector_size;
468 sector += sectors;
469 prot_buf += sectors * bi->tuple_size;
470 total += sectors * bi->tuple_size;
471 BUG_ON(total > bio->bi_integrity->bip_size);
472
Cong Wange8e3c3d2011-11-25 23:14:27 +0800473 kunmap_atomic(kaddr);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200474 }
475
476 return ret;
477}
478
479/**
480 * bio_integrity_verify_fn - Integrity I/O completion worker
481 * @work: Work struct stored in bio to be verified
482 *
483 * Description: This workqueue function is called to complete a READ
484 * request. The function verifies the transferred integrity metadata
485 * and then calls the original bio end_io function.
486 */
487static void bio_integrity_verify_fn(struct work_struct *work)
488{
Jens Axboeb9846792008-06-17 19:05:48 +0200489 struct bio_integrity_payload *bip =
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200490 container_of(work, struct bio_integrity_payload, bip_work);
491 struct bio *bio = bip->bip_bio;
Martin K. Petersen7b24fc42009-01-04 02:43:38 -0500492 int error;
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200493
Martin K. Petersen7b24fc42009-01-04 02:43:38 -0500494 error = bio_integrity_verify(bio);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200495
496 /* Restore original bio completion handler */
497 bio->bi_end_io = bip->bip_end_io;
Martin K. Petersen7b24fc42009-01-04 02:43:38 -0500498 bio_endio(bio, error);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200499}
500
501/**
502 * bio_integrity_endio - Integrity I/O completion function
503 * @bio: Protected bio
504 * @error: Pointer to errno
505 *
506 * Description: Completion for integrity I/O
507 *
508 * Normally I/O completion is done in interrupt context. However,
509 * verifying I/O integrity is a time-consuming task which must be run
510 * in process context. This function postpones completion
511 * accordingly.
512 */
513void bio_integrity_endio(struct bio *bio, int error)
514{
515 struct bio_integrity_payload *bip = bio->bi_integrity;
516
517 BUG_ON(bip->bip_bio != bio);
518
Martin K. Petersen7b24fc42009-01-04 02:43:38 -0500519 /* In case of an I/O error there is no point in verifying the
520 * integrity metadata. Restore original bio end_io handler
521 * and run it.
522 */
523 if (error) {
524 bio->bi_end_io = bip->bip_end_io;
525 bio_endio(bio, error);
526
527 return;
528 }
529
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200530 INIT_WORK(&bip->bip_work, bio_integrity_verify_fn);
531 queue_work(kintegrityd_wq, &bip->bip_work);
532}
533EXPORT_SYMBOL(bio_integrity_endio);
534
535/**
536 * bio_integrity_mark_head - Advance bip_vec skip bytes
537 * @bip: Integrity vector to advance
538 * @skip: Number of bytes to advance it
539 */
Jens Axboeb9846792008-06-17 19:05:48 +0200540void bio_integrity_mark_head(struct bio_integrity_payload *bip,
541 unsigned int skip)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200542{
543 struct bio_vec *iv;
544 unsigned int i;
545
546 bip_for_each_vec(iv, bip, i) {
547 if (skip == 0) {
548 bip->bip_idx = i;
549 return;
550 } else if (skip >= iv->bv_len) {
551 skip -= iv->bv_len;
552 } else { /* skip < iv->bv_len) */
553 iv->bv_offset += skip;
554 iv->bv_len -= skip;
555 bip->bip_idx = i;
556 return;
557 }
558 }
559}
560
561/**
562 * bio_integrity_mark_tail - Truncate bip_vec to be len bytes long
563 * @bip: Integrity vector to truncate
564 * @len: New length of integrity vector
565 */
Jens Axboeb9846792008-06-17 19:05:48 +0200566void bio_integrity_mark_tail(struct bio_integrity_payload *bip,
567 unsigned int len)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200568{
569 struct bio_vec *iv;
570 unsigned int i;
571
572 bip_for_each_vec(iv, bip, i) {
573 if (len == 0) {
574 bip->bip_vcnt = i;
575 return;
576 } else if (len >= iv->bv_len) {
577 len -= iv->bv_len;
578 } else { /* len < iv->bv_len) */
579 iv->bv_len = len;
580 len = 0;
581 }
582 }
583}
584
585/**
586 * bio_integrity_advance - Advance integrity vector
587 * @bio: bio whose integrity vector to update
588 * @bytes_done: number of data bytes that have been completed
589 *
590 * Description: This function calculates how many integrity bytes the
591 * number of completed data bytes correspond to and advances the
592 * integrity vector accordingly.
593 */
594void bio_integrity_advance(struct bio *bio, unsigned int bytes_done)
595{
596 struct bio_integrity_payload *bip = bio->bi_integrity;
597 struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
598 unsigned int nr_sectors;
599
600 BUG_ON(bip == NULL);
601 BUG_ON(bi == NULL);
602
603 nr_sectors = bio_integrity_hw_sectors(bi, bytes_done >> 9);
604 bio_integrity_mark_head(bip, nr_sectors * bi->tuple_size);
605}
606EXPORT_SYMBOL(bio_integrity_advance);
607
608/**
609 * bio_integrity_trim - Trim integrity vector
610 * @bio: bio whose integrity vector to update
611 * @offset: offset to first data sector
612 * @sectors: number of data sectors
613 *
614 * Description: Used to trim the integrity vector in a cloned bio.
615 * The ivec will be advanced corresponding to 'offset' data sectors
616 * and the length will be truncated corresponding to 'len' data
617 * sectors.
618 */
Jens Axboeb9846792008-06-17 19:05:48 +0200619void bio_integrity_trim(struct bio *bio, unsigned int offset,
620 unsigned int sectors)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200621{
622 struct bio_integrity_payload *bip = bio->bi_integrity;
623 struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
624 unsigned int nr_sectors;
625
626 BUG_ON(bip == NULL);
627 BUG_ON(bi == NULL);
628 BUG_ON(!bio_flagged(bio, BIO_CLONED));
629
630 nr_sectors = bio_integrity_hw_sectors(bi, sectors);
631 bip->bip_sector = bip->bip_sector + offset;
632 bio_integrity_mark_head(bip, offset * bi->tuple_size);
633 bio_integrity_mark_tail(bip, sectors * bi->tuple_size);
634}
635EXPORT_SYMBOL(bio_integrity_trim);
636
637/**
638 * bio_integrity_split - Split integrity metadata
639 * @bio: Protected bio
640 * @bp: Resulting bio_pair
641 * @sectors: Offset
642 *
643 * Description: Splits an integrity page into a bio_pair.
644 */
645void bio_integrity_split(struct bio *bio, struct bio_pair *bp, int sectors)
646{
647 struct blk_integrity *bi;
648 struct bio_integrity_payload *bip = bio->bi_integrity;
649 unsigned int nr_sectors;
650
651 if (bio_integrity(bio) == 0)
652 return;
653
654 bi = bdev_get_integrity(bio->bi_bdev);
655 BUG_ON(bi == NULL);
656 BUG_ON(bip->bip_vcnt != 1);
657
658 nr_sectors = bio_integrity_hw_sectors(bi, sectors);
659
660 bp->bio1.bi_integrity = &bp->bip1;
661 bp->bio2.bi_integrity = &bp->bip2;
662
Kent Overstreet5b836362012-09-04 15:20:38 -0700663 bp->iv1 = bip->bip_vec[bip->bip_idx];
664 bp->iv2 = bip->bip_vec[bip->bip_idx];
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200665
Kent Overstreet6fda9812012-10-12 13:18:27 -0700666 bp->bip1.bip_vec = &bp->iv1;
667 bp->bip2.bip_vec = &bp->iv2;
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200668
669 bp->iv1.bv_len = sectors * bi->tuple_size;
670 bp->iv2.bv_offset += sectors * bi->tuple_size;
671 bp->iv2.bv_len -= sectors * bi->tuple_size;
672
673 bp->bip1.bip_sector = bio->bi_integrity->bip_sector;
674 bp->bip2.bip_sector = bio->bi_integrity->bip_sector + nr_sectors;
675
676 bp->bip1.bip_vcnt = bp->bip2.bip_vcnt = 1;
677 bp->bip1.bip_idx = bp->bip2.bip_idx = 0;
678}
679EXPORT_SYMBOL(bio_integrity_split);
680
681/**
682 * bio_integrity_clone - Callback for cloning bios with integrity metadata
683 * @bio: New bio
684 * @bio_src: Original bio
un'ichi Nomura87092692009-03-09 10:40:52 +0100685 * @gfp_mask: Memory allocation mask
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200686 *
687 * Description: Called to allocate a bip when cloning a bio
688 */
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200689int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
Kent Overstreet1e2a410f2012-09-06 15:34:56 -0700690 gfp_t gfp_mask)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200691{
692 struct bio_integrity_payload *bip_src = bio_src->bi_integrity;
693 struct bio_integrity_payload *bip;
694
695 BUG_ON(bip_src == NULL);
696
Kent Overstreet1e2a410f2012-09-06 15:34:56 -0700697 bip = bio_integrity_alloc(bio, gfp_mask, bip_src->bip_vcnt);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200698
699 if (bip == NULL)
700 return -EIO;
701
702 memcpy(bip->bip_vec, bip_src->bip_vec,
703 bip_src->bip_vcnt * sizeof(struct bio_vec));
704
705 bip->bip_sector = bip_src->bip_sector;
706 bip->bip_vcnt = bip_src->bip_vcnt;
707 bip->bip_idx = bip_src->bip_idx;
708
709 return 0;
710}
711EXPORT_SYMBOL(bio_integrity_clone);
712
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200713int bioset_integrity_create(struct bio_set *bs, int pool_size)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200714{
Martin K. Petersena91a2782011-03-17 11:11:05 +0100715 if (bs->bio_integrity_pool)
716 return 0;
717
Kent Overstreet9f060e22012-10-12 15:29:33 -0700718 bs->bio_integrity_pool = mempool_create_slab_pool(pool_size, bip_slab);
719
720 bs->bvec_integrity_pool = biovec_create_pool(bs, pool_size);
721 if (!bs->bvec_integrity_pool)
722 return -1;
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200723
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200724 if (!bs->bio_integrity_pool)
725 return -1;
Martin K. Petersen6d2a78e2009-03-10 08:27:39 +0100726
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200727 return 0;
728}
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200729EXPORT_SYMBOL(bioset_integrity_create);
730
731void bioset_integrity_free(struct bio_set *bs)
732{
733 if (bs->bio_integrity_pool)
734 mempool_destroy(bs->bio_integrity_pool);
Kent Overstreet9f060e22012-10-12 15:29:33 -0700735
736 if (bs->bvec_integrity_pool)
737 mempool_destroy(bs->bio_integrity_pool);
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200738}
739EXPORT_SYMBOL(bioset_integrity_free);
740
741void __init bio_integrity_init(void)
742{
Tejun Heoa6e8dc42011-01-03 15:01:48 +0100743 /*
744 * kintegrityd won't block much but may burn a lot of CPU cycles.
745 * Make it highpri CPU intensive wq with max concurrency of 1.
746 */
747 kintegrityd_wq = alloc_workqueue("kintegrityd", WQ_MEM_RECLAIM |
748 WQ_HIGHPRI | WQ_CPU_INTENSIVE, 1);
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200749 if (!kintegrityd_wq)
750 panic("Failed to create kintegrityd\n");
751
Kent Overstreet9f060e22012-10-12 15:29:33 -0700752 bip_slab = kmem_cache_create("bio_integrity_payload",
753 sizeof(struct bio_integrity_payload) +
754 sizeof(struct bio_vec) * BIP_INLINE_VECS,
755 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
756 if (!bip_slab)
757 panic("Failed to create slab\n");
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200758}