bio-integrity.c 20 KB

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  1. /*
  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. #include <linux/blkdev.h>
  23. #include <linux/mempool.h>
  24. #include <linux/bio.h>
  25. #include <linux/workqueue.h>
  26. static struct kmem_cache *bio_integrity_slab __read_mostly;
  27. static struct workqueue_struct *kintegrityd_wq;
  28. /**
  29. * bio_integrity_alloc_bioset - Allocate integrity payload and attach it to bio
  30. * @bio: bio to attach integrity metadata to
  31. * @gfp_mask: Memory allocation mask
  32. * @nr_vecs: Number of integrity metadata scatter-gather elements
  33. * @bs: bio_set to allocate from
  34. *
  35. * Description: This function prepares a bio for attaching integrity
  36. * metadata. nr_vecs specifies the maximum number of pages containing
  37. * integrity metadata that can be attached.
  38. */
  39. struct bio_integrity_payload *bio_integrity_alloc_bioset(struct bio *bio,
  40. gfp_t gfp_mask,
  41. unsigned int nr_vecs,
  42. struct bio_set *bs)
  43. {
  44. struct bio_integrity_payload *bip;
  45. struct bio_vec *iv;
  46. unsigned long idx;
  47. BUG_ON(bio == NULL);
  48. bip = mempool_alloc(bs->bio_integrity_pool, gfp_mask);
  49. if (unlikely(bip == NULL)) {
  50. printk(KERN_ERR "%s: could not alloc bip\n", __func__);
  51. return NULL;
  52. }
  53. memset(bip, 0, sizeof(*bip));
  54. iv = bvec_alloc_bs(gfp_mask, nr_vecs, &idx, bs);
  55. if (unlikely(iv == NULL)) {
  56. printk(KERN_ERR "%s: could not alloc bip_vec\n", __func__);
  57. mempool_free(bip, bs->bio_integrity_pool);
  58. return NULL;
  59. }
  60. bip->bip_pool = idx;
  61. bip->bip_vec = iv;
  62. bip->bip_bio = bio;
  63. bio->bi_integrity = bip;
  64. return bip;
  65. }
  66. EXPORT_SYMBOL(bio_integrity_alloc_bioset);
  67. /**
  68. * bio_integrity_alloc - Allocate integrity payload and attach it to bio
  69. * @bio: bio to attach integrity metadata to
  70. * @gfp_mask: Memory allocation mask
  71. * @nr_vecs: Number of integrity metadata scatter-gather elements
  72. *
  73. * Description: This function prepares a bio for attaching integrity
  74. * metadata. nr_vecs specifies the maximum number of pages containing
  75. * integrity metadata that can be attached.
  76. */
  77. struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio,
  78. gfp_t gfp_mask,
  79. unsigned int nr_vecs)
  80. {
  81. return bio_integrity_alloc_bioset(bio, gfp_mask, nr_vecs, fs_bio_set);
  82. }
  83. EXPORT_SYMBOL(bio_integrity_alloc);
  84. /**
  85. * bio_integrity_free - Free bio integrity payload
  86. * @bio: bio containing bip to be freed
  87. * @bs: bio_set this bio was allocated from
  88. *
  89. * Description: Used to free the integrity portion of a bio. Usually
  90. * called from bio_free().
  91. */
  92. void bio_integrity_free(struct bio *bio, struct bio_set *bs)
  93. {
  94. struct bio_integrity_payload *bip = bio->bi_integrity;
  95. BUG_ON(bip == NULL);
  96. /* A cloned bio doesn't own the integrity metadata */
  97. if (!bio_flagged(bio, BIO_CLONED) && bip->bip_buf != NULL)
  98. kfree(bip->bip_buf);
  99. mempool_free(bip->bip_vec, bs->bvec_pools[bip->bip_pool]);
  100. mempool_free(bip, bs->bio_integrity_pool);
  101. bio->bi_integrity = NULL;
  102. }
  103. EXPORT_SYMBOL(bio_integrity_free);
  104. /**
  105. * bio_integrity_add_page - Attach integrity metadata
  106. * @bio: bio to update
  107. * @page: page containing integrity metadata
  108. * @len: number of bytes of integrity metadata in page
  109. * @offset: start offset within page
  110. *
  111. * Description: Attach a page containing integrity metadata to bio.
  112. */
  113. int bio_integrity_add_page(struct bio *bio, struct page *page,
  114. unsigned int len, unsigned int offset)
  115. {
  116. struct bio_integrity_payload *bip = bio->bi_integrity;
  117. struct bio_vec *iv;
  118. if (bip->bip_vcnt >= bvec_nr_vecs(bip->bip_pool)) {
  119. printk(KERN_ERR "%s: bip_vec full\n", __func__);
  120. return 0;
  121. }
  122. iv = bip_vec_idx(bip, bip->bip_vcnt);
  123. BUG_ON(iv == NULL);
  124. BUG_ON(iv->bv_page != NULL);
  125. iv->bv_page = page;
  126. iv->bv_len = len;
  127. iv->bv_offset = offset;
  128. bip->bip_vcnt++;
  129. return len;
  130. }
  131. EXPORT_SYMBOL(bio_integrity_add_page);
  132. static struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
  133. {
  134. return bdev->bd_disk->integrity;
  135. }
  136. static int bdev_integrity_enabled(struct block_device *bdev, int rw)
  137. {
  138. struct blk_integrity *bi = bdev_get_integrity(bdev);
  139. if (bi == NULL)
  140. return 0;
  141. if (rw == READ && bi->verify_fn != NULL &&
  142. (bi->flags & INTEGRITY_FLAG_READ))
  143. return 1;
  144. if (rw == WRITE && bi->generate_fn != NULL &&
  145. (bi->flags & INTEGRITY_FLAG_WRITE))
  146. return 1;
  147. return 0;
  148. }
  149. /**
  150. * bio_integrity_enabled - Check whether integrity can be passed
  151. * @bio: bio to check
  152. *
  153. * Description: Determines whether bio_integrity_prep() can be called
  154. * on this bio or not. bio data direction and target device must be
  155. * set prior to calling. The functions honors the write_generate and
  156. * read_verify flags in sysfs.
  157. */
  158. int bio_integrity_enabled(struct bio *bio)
  159. {
  160. /* Already protected? */
  161. if (bio_integrity(bio))
  162. return 0;
  163. return bdev_integrity_enabled(bio->bi_bdev, bio_data_dir(bio));
  164. }
  165. EXPORT_SYMBOL(bio_integrity_enabled);
  166. /**
  167. * bio_integrity_hw_sectors - Convert 512b sectors to hardware ditto
  168. * @bi: blk_integrity profile for device
  169. * @sectors: Number of 512 sectors to convert
  170. *
  171. * Description: The block layer calculates everything in 512 byte
  172. * sectors but integrity metadata is done in terms of the hardware
  173. * sector size of the storage device. Convert the block layer sectors
  174. * to physical sectors.
  175. */
  176. static inline unsigned int bio_integrity_hw_sectors(struct blk_integrity *bi,
  177. unsigned int sectors)
  178. {
  179. /* At this point there are only 512b or 4096b DIF/EPP devices */
  180. if (bi->sector_size == 4096)
  181. return sectors >>= 3;
  182. return sectors;
  183. }
  184. /**
  185. * bio_integrity_tag_size - Retrieve integrity tag space
  186. * @bio: bio to inspect
  187. *
  188. * Description: Returns the maximum number of tag bytes that can be
  189. * attached to this bio. Filesystems can use this to determine how
  190. * much metadata to attach to an I/O.
  191. */
  192. unsigned int bio_integrity_tag_size(struct bio *bio)
  193. {
  194. struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
  195. BUG_ON(bio->bi_size == 0);
  196. return bi->tag_size * (bio->bi_size / bi->sector_size);
  197. }
  198. EXPORT_SYMBOL(bio_integrity_tag_size);
  199. int bio_integrity_tag(struct bio *bio, void *tag_buf, unsigned int len, int set)
  200. {
  201. struct bio_integrity_payload *bip = bio->bi_integrity;
  202. struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
  203. unsigned int nr_sectors;
  204. BUG_ON(bip->bip_buf == NULL);
  205. if (bi->tag_size == 0)
  206. return -1;
  207. nr_sectors = bio_integrity_hw_sectors(bi,
  208. DIV_ROUND_UP(len, bi->tag_size));
  209. if (nr_sectors * bi->tuple_size > bip->bip_size) {
  210. printk(KERN_ERR "%s: tag too big for bio: %u > %u\n",
  211. __func__, nr_sectors * bi->tuple_size, bip->bip_size);
  212. return -1;
  213. }
  214. if (set)
  215. bi->set_tag_fn(bip->bip_buf, tag_buf, nr_sectors);
  216. else
  217. bi->get_tag_fn(bip->bip_buf, tag_buf, nr_sectors);
  218. return 0;
  219. }
  220. /**
  221. * bio_integrity_set_tag - Attach a tag buffer to a bio
  222. * @bio: bio to attach buffer to
  223. * @tag_buf: Pointer to a buffer containing tag data
  224. * @len: Length of the included buffer
  225. *
  226. * Description: Use this function to tag a bio by leveraging the extra
  227. * space provided by devices formatted with integrity protection. The
  228. * size of the integrity buffer must be <= to the size reported by
  229. * bio_integrity_tag_size().
  230. */
  231. int bio_integrity_set_tag(struct bio *bio, void *tag_buf, unsigned int len)
  232. {
  233. BUG_ON(bio_data_dir(bio) != WRITE);
  234. return bio_integrity_tag(bio, tag_buf, len, 1);
  235. }
  236. EXPORT_SYMBOL(bio_integrity_set_tag);
  237. /**
  238. * bio_integrity_get_tag - Retrieve a tag buffer from a bio
  239. * @bio: bio to retrieve buffer from
  240. * @tag_buf: Pointer to a buffer for the tag data
  241. * @len: Length of the target buffer
  242. *
  243. * Description: Use this function to retrieve the tag buffer from a
  244. * completed I/O. The size of the integrity buffer must be <= to the
  245. * size reported by bio_integrity_tag_size().
  246. */
  247. int bio_integrity_get_tag(struct bio *bio, void *tag_buf, unsigned int len)
  248. {
  249. BUG_ON(bio_data_dir(bio) != READ);
  250. return bio_integrity_tag(bio, tag_buf, len, 0);
  251. }
  252. EXPORT_SYMBOL(bio_integrity_get_tag);
  253. /**
  254. * bio_integrity_generate - Generate integrity metadata for a bio
  255. * @bio: bio to generate integrity metadata for
  256. *
  257. * Description: Generates integrity metadata for a bio by calling the
  258. * block device's generation callback function. The bio must have a
  259. * bip attached with enough room to accommodate the generated
  260. * integrity metadata.
  261. */
  262. static void bio_integrity_generate(struct bio *bio)
  263. {
  264. struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
  265. struct blk_integrity_exchg bix;
  266. struct bio_vec *bv;
  267. sector_t sector = bio->bi_sector;
  268. unsigned int i, sectors, total;
  269. void *prot_buf = bio->bi_integrity->bip_buf;
  270. total = 0;
  271. bix.disk_name = bio->bi_bdev->bd_disk->disk_name;
  272. bix.sector_size = bi->sector_size;
  273. bio_for_each_segment(bv, bio, i) {
  274. void *kaddr = kmap_atomic(bv->bv_page, KM_USER0);
  275. bix.data_buf = kaddr + bv->bv_offset;
  276. bix.data_size = bv->bv_len;
  277. bix.prot_buf = prot_buf;
  278. bix.sector = sector;
  279. bi->generate_fn(&bix);
  280. sectors = bv->bv_len / bi->sector_size;
  281. sector += sectors;
  282. prot_buf += sectors * bi->tuple_size;
  283. total += sectors * bi->tuple_size;
  284. BUG_ON(total > bio->bi_integrity->bip_size);
  285. kunmap_atomic(kaddr, KM_USER0);
  286. }
  287. }
  288. static inline unsigned short blk_integrity_tuple_size(struct blk_integrity *bi)
  289. {
  290. if (bi)
  291. return bi->tuple_size;
  292. return 0;
  293. }
  294. /**
  295. * bio_integrity_prep - Prepare bio for integrity I/O
  296. * @bio: bio to prepare
  297. *
  298. * Description: Allocates a buffer for integrity metadata, maps the
  299. * pages and attaches them to a bio. The bio must have data
  300. * direction, target device and start sector set priot to calling. In
  301. * the WRITE case, integrity metadata will be generated using the
  302. * block device's integrity function. In the READ case, the buffer
  303. * will be prepared for DMA and a suitable end_io handler set up.
  304. */
  305. int bio_integrity_prep(struct bio *bio)
  306. {
  307. struct bio_integrity_payload *bip;
  308. struct blk_integrity *bi;
  309. struct request_queue *q;
  310. void *buf;
  311. unsigned long start, end;
  312. unsigned int len, nr_pages;
  313. unsigned int bytes, offset, i;
  314. unsigned int sectors;
  315. bi = bdev_get_integrity(bio->bi_bdev);
  316. q = bdev_get_queue(bio->bi_bdev);
  317. BUG_ON(bi == NULL);
  318. BUG_ON(bio_integrity(bio));
  319. sectors = bio_integrity_hw_sectors(bi, bio_sectors(bio));
  320. /* Allocate kernel buffer for protection data */
  321. len = sectors * blk_integrity_tuple_size(bi);
  322. buf = kmalloc(len, GFP_NOIO | __GFP_NOFAIL | q->bounce_gfp);
  323. if (unlikely(buf == NULL)) {
  324. printk(KERN_ERR "could not allocate integrity buffer\n");
  325. return -EIO;
  326. }
  327. end = (((unsigned long) buf) + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
  328. start = ((unsigned long) buf) >> PAGE_SHIFT;
  329. nr_pages = end - start;
  330. /* Allocate bio integrity payload and integrity vectors */
  331. bip = bio_integrity_alloc(bio, GFP_NOIO, nr_pages);
  332. if (unlikely(bip == NULL)) {
  333. printk(KERN_ERR "could not allocate data integrity bioset\n");
  334. kfree(buf);
  335. return -EIO;
  336. }
  337. bip->bip_buf = buf;
  338. bip->bip_size = len;
  339. bip->bip_sector = bio->bi_sector;
  340. /* Map it */
  341. offset = offset_in_page(buf);
  342. for (i = 0 ; i < nr_pages ; i++) {
  343. int ret;
  344. bytes = PAGE_SIZE - offset;
  345. if (len <= 0)
  346. break;
  347. if (bytes > len)
  348. bytes = len;
  349. ret = bio_integrity_add_page(bio, virt_to_page(buf),
  350. bytes, offset);
  351. if (ret == 0)
  352. return 0;
  353. if (ret < bytes)
  354. break;
  355. buf += bytes;
  356. len -= bytes;
  357. offset = 0;
  358. }
  359. /* Install custom I/O completion handler if read verify is enabled */
  360. if (bio_data_dir(bio) == READ) {
  361. bip->bip_end_io = bio->bi_end_io;
  362. bio->bi_end_io = bio_integrity_endio;
  363. }
  364. /* Auto-generate integrity metadata if this is a write */
  365. if (bio_data_dir(bio) == WRITE)
  366. bio_integrity_generate(bio);
  367. return 0;
  368. }
  369. EXPORT_SYMBOL(bio_integrity_prep);
  370. /**
  371. * bio_integrity_verify - Verify integrity metadata for a bio
  372. * @bio: bio to verify
  373. *
  374. * Description: This function is called to verify the integrity of a
  375. * bio. The data in the bio io_vec is compared to the integrity
  376. * metadata returned by the HBA.
  377. */
  378. static int bio_integrity_verify(struct bio *bio)
  379. {
  380. struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
  381. struct blk_integrity_exchg bix;
  382. struct bio_vec *bv;
  383. sector_t sector = bio->bi_integrity->bip_sector;
  384. unsigned int i, sectors, total, ret;
  385. void *prot_buf = bio->bi_integrity->bip_buf;
  386. ret = total = 0;
  387. bix.disk_name = bio->bi_bdev->bd_disk->disk_name;
  388. bix.sector_size = bi->sector_size;
  389. bio_for_each_segment(bv, bio, i) {
  390. void *kaddr = kmap_atomic(bv->bv_page, KM_USER0);
  391. bix.data_buf = kaddr + bv->bv_offset;
  392. bix.data_size = bv->bv_len;
  393. bix.prot_buf = prot_buf;
  394. bix.sector = sector;
  395. ret = bi->verify_fn(&bix);
  396. if (ret) {
  397. kunmap_atomic(kaddr, KM_USER0);
  398. break;
  399. }
  400. sectors = bv->bv_len / bi->sector_size;
  401. sector += sectors;
  402. prot_buf += sectors * bi->tuple_size;
  403. total += sectors * bi->tuple_size;
  404. BUG_ON(total > bio->bi_integrity->bip_size);
  405. kunmap_atomic(kaddr, KM_USER0);
  406. }
  407. return ret;
  408. }
  409. /**
  410. * bio_integrity_verify_fn - Integrity I/O completion worker
  411. * @work: Work struct stored in bio to be verified
  412. *
  413. * Description: This workqueue function is called to complete a READ
  414. * request. The function verifies the transferred integrity metadata
  415. * and then calls the original bio end_io function.
  416. */
  417. static void bio_integrity_verify_fn(struct work_struct *work)
  418. {
  419. struct bio_integrity_payload *bip =
  420. container_of(work, struct bio_integrity_payload, bip_work);
  421. struct bio *bio = bip->bip_bio;
  422. int error = bip->bip_error;
  423. if (bio_integrity_verify(bio)) {
  424. clear_bit(BIO_UPTODATE, &bio->bi_flags);
  425. error = -EIO;
  426. }
  427. /* Restore original bio completion handler */
  428. bio->bi_end_io = bip->bip_end_io;
  429. if (bio->bi_end_io)
  430. bio->bi_end_io(bio, error);
  431. }
  432. /**
  433. * bio_integrity_endio - Integrity I/O completion function
  434. * @bio: Protected bio
  435. * @error: Pointer to errno
  436. *
  437. * Description: Completion for integrity I/O
  438. *
  439. * Normally I/O completion is done in interrupt context. However,
  440. * verifying I/O integrity is a time-consuming task which must be run
  441. * in process context. This function postpones completion
  442. * accordingly.
  443. */
  444. void bio_integrity_endio(struct bio *bio, int error)
  445. {
  446. struct bio_integrity_payload *bip = bio->bi_integrity;
  447. BUG_ON(bip->bip_bio != bio);
  448. bip->bip_error = error;
  449. INIT_WORK(&bip->bip_work, bio_integrity_verify_fn);
  450. queue_work(kintegrityd_wq, &bip->bip_work);
  451. }
  452. EXPORT_SYMBOL(bio_integrity_endio);
  453. /**
  454. * bio_integrity_mark_head - Advance bip_vec skip bytes
  455. * @bip: Integrity vector to advance
  456. * @skip: Number of bytes to advance it
  457. */
  458. void bio_integrity_mark_head(struct bio_integrity_payload *bip,
  459. unsigned int skip)
  460. {
  461. struct bio_vec *iv;
  462. unsigned int i;
  463. bip_for_each_vec(iv, bip, i) {
  464. if (skip == 0) {
  465. bip->bip_idx = i;
  466. return;
  467. } else if (skip >= iv->bv_len) {
  468. skip -= iv->bv_len;
  469. } else { /* skip < iv->bv_len) */
  470. iv->bv_offset += skip;
  471. iv->bv_len -= skip;
  472. bip->bip_idx = i;
  473. return;
  474. }
  475. }
  476. }
  477. /**
  478. * bio_integrity_mark_tail - Truncate bip_vec to be len bytes long
  479. * @bip: Integrity vector to truncate
  480. * @len: New length of integrity vector
  481. */
  482. void bio_integrity_mark_tail(struct bio_integrity_payload *bip,
  483. unsigned int len)
  484. {
  485. struct bio_vec *iv;
  486. unsigned int i;
  487. bip_for_each_vec(iv, bip, i) {
  488. if (len == 0) {
  489. bip->bip_vcnt = i;
  490. return;
  491. } else if (len >= iv->bv_len) {
  492. len -= iv->bv_len;
  493. } else { /* len < iv->bv_len) */
  494. iv->bv_len = len;
  495. len = 0;
  496. }
  497. }
  498. }
  499. /**
  500. * bio_integrity_advance - Advance integrity vector
  501. * @bio: bio whose integrity vector to update
  502. * @bytes_done: number of data bytes that have been completed
  503. *
  504. * Description: This function calculates how many integrity bytes the
  505. * number of completed data bytes correspond to and advances the
  506. * integrity vector accordingly.
  507. */
  508. void bio_integrity_advance(struct bio *bio, unsigned int bytes_done)
  509. {
  510. struct bio_integrity_payload *bip = bio->bi_integrity;
  511. struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
  512. unsigned int nr_sectors;
  513. BUG_ON(bip == NULL);
  514. BUG_ON(bi == NULL);
  515. nr_sectors = bio_integrity_hw_sectors(bi, bytes_done >> 9);
  516. bio_integrity_mark_head(bip, nr_sectors * bi->tuple_size);
  517. }
  518. EXPORT_SYMBOL(bio_integrity_advance);
  519. /**
  520. * bio_integrity_trim - Trim integrity vector
  521. * @bio: bio whose integrity vector to update
  522. * @offset: offset to first data sector
  523. * @sectors: number of data sectors
  524. *
  525. * Description: Used to trim the integrity vector in a cloned bio.
  526. * The ivec will be advanced corresponding to 'offset' data sectors
  527. * and the length will be truncated corresponding to 'len' data
  528. * sectors.
  529. */
  530. void bio_integrity_trim(struct bio *bio, unsigned int offset,
  531. unsigned int sectors)
  532. {
  533. struct bio_integrity_payload *bip = bio->bi_integrity;
  534. struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
  535. unsigned int nr_sectors;
  536. BUG_ON(bip == NULL);
  537. BUG_ON(bi == NULL);
  538. BUG_ON(!bio_flagged(bio, BIO_CLONED));
  539. nr_sectors = bio_integrity_hw_sectors(bi, sectors);
  540. bip->bip_sector = bip->bip_sector + offset;
  541. bio_integrity_mark_head(bip, offset * bi->tuple_size);
  542. bio_integrity_mark_tail(bip, sectors * bi->tuple_size);
  543. }
  544. EXPORT_SYMBOL(bio_integrity_trim);
  545. /**
  546. * bio_integrity_split - Split integrity metadata
  547. * @bio: Protected bio
  548. * @bp: Resulting bio_pair
  549. * @sectors: Offset
  550. *
  551. * Description: Splits an integrity page into a bio_pair.
  552. */
  553. void bio_integrity_split(struct bio *bio, struct bio_pair *bp, int sectors)
  554. {
  555. struct blk_integrity *bi;
  556. struct bio_integrity_payload *bip = bio->bi_integrity;
  557. unsigned int nr_sectors;
  558. if (bio_integrity(bio) == 0)
  559. return;
  560. bi = bdev_get_integrity(bio->bi_bdev);
  561. BUG_ON(bi == NULL);
  562. BUG_ON(bip->bip_vcnt != 1);
  563. nr_sectors = bio_integrity_hw_sectors(bi, sectors);
  564. bp->bio1.bi_integrity = &bp->bip1;
  565. bp->bio2.bi_integrity = &bp->bip2;
  566. bp->iv1 = bip->bip_vec[0];
  567. bp->iv2 = bip->bip_vec[0];
  568. bp->bip1.bip_vec = &bp->iv1;
  569. bp->bip2.bip_vec = &bp->iv2;
  570. bp->iv1.bv_len = sectors * bi->tuple_size;
  571. bp->iv2.bv_offset += sectors * bi->tuple_size;
  572. bp->iv2.bv_len -= sectors * bi->tuple_size;
  573. bp->bip1.bip_sector = bio->bi_integrity->bip_sector;
  574. bp->bip2.bip_sector = bio->bi_integrity->bip_sector + nr_sectors;
  575. bp->bip1.bip_vcnt = bp->bip2.bip_vcnt = 1;
  576. bp->bip1.bip_idx = bp->bip2.bip_idx = 0;
  577. }
  578. EXPORT_SYMBOL(bio_integrity_split);
  579. /**
  580. * bio_integrity_clone - Callback for cloning bios with integrity metadata
  581. * @bio: New bio
  582. * @bio_src: Original bio
  583. * @bs: bio_set to allocate bip from
  584. *
  585. * Description: Called to allocate a bip when cloning a bio
  586. */
  587. int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
  588. struct bio_set *bs)
  589. {
  590. struct bio_integrity_payload *bip_src = bio_src->bi_integrity;
  591. struct bio_integrity_payload *bip;
  592. BUG_ON(bip_src == NULL);
  593. bip = bio_integrity_alloc_bioset(bio, GFP_NOIO, bip_src->bip_vcnt, bs);
  594. if (bip == NULL)
  595. return -EIO;
  596. memcpy(bip->bip_vec, bip_src->bip_vec,
  597. bip_src->bip_vcnt * sizeof(struct bio_vec));
  598. bip->bip_sector = bip_src->bip_sector;
  599. bip->bip_vcnt = bip_src->bip_vcnt;
  600. bip->bip_idx = bip_src->bip_idx;
  601. return 0;
  602. }
  603. EXPORT_SYMBOL(bio_integrity_clone);
  604. int bioset_integrity_create(struct bio_set *bs, int pool_size)
  605. {
  606. bs->bio_integrity_pool = mempool_create_slab_pool(pool_size,
  607. bio_integrity_slab);
  608. if (!bs->bio_integrity_pool)
  609. return -1;
  610. return 0;
  611. }
  612. EXPORT_SYMBOL(bioset_integrity_create);
  613. void bioset_integrity_free(struct bio_set *bs)
  614. {
  615. if (bs->bio_integrity_pool)
  616. mempool_destroy(bs->bio_integrity_pool);
  617. }
  618. EXPORT_SYMBOL(bioset_integrity_free);
  619. void __init bio_integrity_init_slab(void)
  620. {
  621. bio_integrity_slab = KMEM_CACHE(bio_integrity_payload,
  622. SLAB_HWCACHE_ALIGN|SLAB_PANIC);
  623. }
  624. static int __init integrity_init(void)
  625. {
  626. kintegrityd_wq = create_workqueue("kintegrityd");
  627. if (!kintegrityd_wq)
  628. panic("Failed to create kintegrityd\n");
  629. return 0;
  630. }
  631. subsys_initcall(integrity_init);