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7ba1ba12 MP |
1 | /* |
2 | * bio-integrity.c - bio data integrity extensions | |
3 | * | |
7878cba9 | 4 | * Copyright (C) 2007, 2008, 2009 Oracle Corporation |
7ba1ba12 MP |
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> | |
afeacc8c | 25 | #include <linux/export.h> |
7ba1ba12 MP |
26 | #include <linux/bio.h> |
27 | #include <linux/workqueue.h> | |
5a0e3ad6 | 28 | #include <linux/slab.h> |
7ba1ba12 | 29 | |
7878cba9 MP |
30 | struct integrity_slab { |
31 | struct kmem_cache *slab; | |
32 | unsigned short nr_vecs; | |
33 | char name[8]; | |
34 | }; | |
35 | ||
36 | #define IS(x) { .nr_vecs = x, .name = "bip-"__stringify(x) } | |
37 | struct integrity_slab bip_slab[BIOVEC_NR_POOLS] __read_mostly = { | |
38 | IS(1), IS(4), IS(16), IS(64), IS(128), IS(BIO_MAX_PAGES), | |
39 | }; | |
40 | #undef IS | |
41 | ||
7ba1ba12 MP |
42 | static struct workqueue_struct *kintegrityd_wq; |
43 | ||
7878cba9 MP |
44 | static inline unsigned int vecs_to_idx(unsigned int nr) |
45 | { | |
46 | switch (nr) { | |
47 | case 1: | |
48 | return 0; | |
49 | case 2 ... 4: | |
50 | return 1; | |
51 | case 5 ... 16: | |
52 | return 2; | |
53 | case 17 ... 64: | |
54 | return 3; | |
55 | case 65 ... 128: | |
56 | return 4; | |
57 | case 129 ... BIO_MAX_PAGES: | |
58 | return 5; | |
59 | default: | |
60 | BUG(); | |
61 | } | |
62 | } | |
63 | ||
64 | static inline int use_bip_pool(unsigned int idx) | |
65 | { | |
9e9432c2 | 66 | if (idx == BIOVEC_MAX_IDX) |
7878cba9 MP |
67 | return 1; |
68 | ||
69 | return 0; | |
70 | } | |
71 | ||
7ba1ba12 | 72 | /** |
1e2a410f | 73 | * bio_integrity_alloc - Allocate integrity payload and attach it to bio |
7ba1ba12 MP |
74 | * @bio: bio to attach integrity metadata to |
75 | * @gfp_mask: Memory allocation mask | |
76 | * @nr_vecs: Number of integrity metadata scatter-gather elements | |
7ba1ba12 MP |
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 | */ | |
1e2a410f KO |
82 | struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio, |
83 | gfp_t gfp_mask, | |
84 | unsigned int nr_vecs) | |
7ba1ba12 MP |
85 | { |
86 | struct bio_integrity_payload *bip; | |
7878cba9 | 87 | unsigned int idx = vecs_to_idx(nr_vecs); |
1e2a410f KO |
88 | struct bio_set *bs = bio->bi_pool; |
89 | ||
90 | if (!bs) | |
91 | bs = fs_bio_set; | |
7ba1ba12 MP |
92 | |
93 | BUG_ON(bio == NULL); | |
7878cba9 | 94 | bip = NULL; |
7ba1ba12 | 95 | |
7878cba9 MP |
96 | /* Lower order allocations come straight from slab */ |
97 | if (!use_bip_pool(idx)) | |
98 | bip = kmem_cache_alloc(bip_slab[idx].slab, gfp_mask); | |
7ba1ba12 | 99 | |
7878cba9 MP |
100 | /* Use mempool if lower order alloc failed or max vecs were requested */ |
101 | if (bip == NULL) { | |
9e9432c2 | 102 | idx = BIOVEC_MAX_IDX; /* so we free the payload properly later */ |
7878cba9 | 103 | bip = mempool_alloc(bs->bio_integrity_pool, gfp_mask); |
7ba1ba12 | 104 | |
7878cba9 MP |
105 | if (unlikely(bip == NULL)) { |
106 | printk(KERN_ERR "%s: could not alloc bip\n", __func__); | |
107 | return NULL; | |
108 | } | |
7ba1ba12 MP |
109 | } |
110 | ||
7878cba9 MP |
111 | memset(bip, 0, sizeof(*bip)); |
112 | ||
113 | bip->bip_slab = idx; | |
7ba1ba12 MP |
114 | bip->bip_bio = bio; |
115 | bio->bi_integrity = bip; | |
116 | ||
117 | return bip; | |
118 | } | |
7ba1ba12 MP |
119 | EXPORT_SYMBOL(bio_integrity_alloc); |
120 | ||
121 | /** | |
122 | * bio_integrity_free - Free bio integrity payload | |
123 | * @bio: bio containing bip to be freed | |
7ba1ba12 MP |
124 | * |
125 | * Description: Used to free the integrity portion of a bio. Usually | |
126 | * called from bio_free(). | |
127 | */ | |
1e2a410f | 128 | void bio_integrity_free(struct bio *bio) |
7ba1ba12 MP |
129 | { |
130 | struct bio_integrity_payload *bip = bio->bi_integrity; | |
1e2a410f KO |
131 | struct bio_set *bs = bio->bi_pool; |
132 | ||
133 | if (!bs) | |
134 | bs = fs_bio_set; | |
7ba1ba12 MP |
135 | |
136 | BUG_ON(bip == NULL); | |
137 | ||
138 | /* A cloned bio doesn't own the integrity metadata */ | |
74aa8c2c MP |
139 | if (!bio_flagged(bio, BIO_CLONED) && !bio_flagged(bio, BIO_FS_INTEGRITY) |
140 | && bip->bip_buf != NULL) | |
7ba1ba12 MP |
141 | kfree(bip->bip_buf); |
142 | ||
7878cba9 MP |
143 | if (use_bip_pool(bip->bip_slab)) |
144 | mempool_free(bip, bs->bio_integrity_pool); | |
145 | else | |
146 | kmem_cache_free(bip_slab[bip->bip_slab].slab, bip); | |
7ba1ba12 MP |
147 | |
148 | bio->bi_integrity = NULL; | |
149 | } | |
150 | EXPORT_SYMBOL(bio_integrity_free); | |
151 | ||
152 | /** | |
153 | * bio_integrity_add_page - Attach integrity metadata | |
154 | * @bio: bio to update | |
155 | * @page: page containing integrity metadata | |
156 | * @len: number of bytes of integrity metadata in page | |
157 | * @offset: start offset within page | |
158 | * | |
159 | * Description: Attach a page containing integrity metadata to bio. | |
160 | */ | |
161 | int bio_integrity_add_page(struct bio *bio, struct page *page, | |
162 | unsigned int len, unsigned int offset) | |
163 | { | |
164 | struct bio_integrity_payload *bip = bio->bi_integrity; | |
165 | struct bio_vec *iv; | |
166 | ||
7878cba9 | 167 | if (bip->bip_vcnt >= bvec_nr_vecs(bip->bip_slab)) { |
7ba1ba12 MP |
168 | printk(KERN_ERR "%s: bip_vec full\n", __func__); |
169 | return 0; | |
170 | } | |
171 | ||
172 | iv = bip_vec_idx(bip, bip->bip_vcnt); | |
173 | BUG_ON(iv == NULL); | |
7ba1ba12 MP |
174 | |
175 | iv->bv_page = page; | |
176 | iv->bv_len = len; | |
177 | iv->bv_offset = offset; | |
178 | bip->bip_vcnt++; | |
179 | ||
180 | return len; | |
181 | } | |
182 | EXPORT_SYMBOL(bio_integrity_add_page); | |
183 | ||
9c02f2b0 JA |
184 | static int bdev_integrity_enabled(struct block_device *bdev, int rw) |
185 | { | |
186 | struct blk_integrity *bi = bdev_get_integrity(bdev); | |
187 | ||
188 | if (bi == NULL) | |
189 | return 0; | |
190 | ||
191 | if (rw == READ && bi->verify_fn != NULL && | |
192 | (bi->flags & INTEGRITY_FLAG_READ)) | |
193 | return 1; | |
194 | ||
195 | if (rw == WRITE && bi->generate_fn != NULL && | |
196 | (bi->flags & INTEGRITY_FLAG_WRITE)) | |
197 | return 1; | |
198 | ||
199 | return 0; | |
200 | } | |
201 | ||
7ba1ba12 MP |
202 | /** |
203 | * bio_integrity_enabled - Check whether integrity can be passed | |
204 | * @bio: bio to check | |
205 | * | |
206 | * Description: Determines whether bio_integrity_prep() can be called | |
207 | * on this bio or not. bio data direction and target device must be | |
208 | * set prior to calling. The functions honors the write_generate and | |
209 | * read_verify flags in sysfs. | |
210 | */ | |
211 | int bio_integrity_enabled(struct bio *bio) | |
212 | { | |
213 | /* Already protected? */ | |
214 | if (bio_integrity(bio)) | |
215 | return 0; | |
216 | ||
217 | return bdev_integrity_enabled(bio->bi_bdev, bio_data_dir(bio)); | |
218 | } | |
219 | EXPORT_SYMBOL(bio_integrity_enabled); | |
220 | ||
221 | /** | |
222 | * bio_integrity_hw_sectors - Convert 512b sectors to hardware ditto | |
223 | * @bi: blk_integrity profile for device | |
224 | * @sectors: Number of 512 sectors to convert | |
225 | * | |
226 | * Description: The block layer calculates everything in 512 byte | |
227 | * sectors but integrity metadata is done in terms of the hardware | |
228 | * sector size of the storage device. Convert the block layer sectors | |
229 | * to physical sectors. | |
230 | */ | |
b984679e JA |
231 | static inline unsigned int bio_integrity_hw_sectors(struct blk_integrity *bi, |
232 | unsigned int sectors) | |
7ba1ba12 MP |
233 | { |
234 | /* At this point there are only 512b or 4096b DIF/EPP devices */ | |
235 | if (bi->sector_size == 4096) | |
236 | return sectors >>= 3; | |
237 | ||
238 | return sectors; | |
239 | } | |
240 | ||
241 | /** | |
242 | * bio_integrity_tag_size - Retrieve integrity tag space | |
243 | * @bio: bio to inspect | |
244 | * | |
245 | * Description: Returns the maximum number of tag bytes that can be | |
246 | * attached to this bio. Filesystems can use this to determine how | |
247 | * much metadata to attach to an I/O. | |
248 | */ | |
249 | unsigned int bio_integrity_tag_size(struct bio *bio) | |
250 | { | |
251 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); | |
252 | ||
253 | BUG_ON(bio->bi_size == 0); | |
254 | ||
255 | return bi->tag_size * (bio->bi_size / bi->sector_size); | |
256 | } | |
257 | EXPORT_SYMBOL(bio_integrity_tag_size); | |
258 | ||
259 | int bio_integrity_tag(struct bio *bio, void *tag_buf, unsigned int len, int set) | |
260 | { | |
261 | struct bio_integrity_payload *bip = bio->bi_integrity; | |
262 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); | |
263 | unsigned int nr_sectors; | |
264 | ||
265 | BUG_ON(bip->bip_buf == NULL); | |
266 | ||
267 | if (bi->tag_size == 0) | |
268 | return -1; | |
269 | ||
b984679e JA |
270 | nr_sectors = bio_integrity_hw_sectors(bi, |
271 | DIV_ROUND_UP(len, bi->tag_size)); | |
7ba1ba12 MP |
272 | |
273 | if (nr_sectors * bi->tuple_size > bip->bip_size) { | |
274 | printk(KERN_ERR "%s: tag too big for bio: %u > %u\n", | |
275 | __func__, nr_sectors * bi->tuple_size, bip->bip_size); | |
276 | return -1; | |
277 | } | |
278 | ||
279 | if (set) | |
280 | bi->set_tag_fn(bip->bip_buf, tag_buf, nr_sectors); | |
281 | else | |
282 | bi->get_tag_fn(bip->bip_buf, tag_buf, nr_sectors); | |
283 | ||
284 | return 0; | |
285 | } | |
286 | ||
287 | /** | |
288 | * bio_integrity_set_tag - Attach a tag buffer to a bio | |
289 | * @bio: bio to attach buffer to | |
290 | * @tag_buf: Pointer to a buffer containing tag data | |
291 | * @len: Length of the included buffer | |
292 | * | |
293 | * Description: Use this function to tag a bio by leveraging the extra | |
294 | * space provided by devices formatted with integrity protection. The | |
295 | * size of the integrity buffer must be <= to the size reported by | |
296 | * bio_integrity_tag_size(). | |
297 | */ | |
298 | int bio_integrity_set_tag(struct bio *bio, void *tag_buf, unsigned int len) | |
299 | { | |
300 | BUG_ON(bio_data_dir(bio) != WRITE); | |
301 | ||
302 | return bio_integrity_tag(bio, tag_buf, len, 1); | |
303 | } | |
304 | EXPORT_SYMBOL(bio_integrity_set_tag); | |
305 | ||
306 | /** | |
307 | * bio_integrity_get_tag - Retrieve a tag buffer from a bio | |
308 | * @bio: bio to retrieve buffer from | |
309 | * @tag_buf: Pointer to a buffer for the tag data | |
310 | * @len: Length of the target buffer | |
311 | * | |
312 | * Description: Use this function to retrieve the tag buffer from a | |
313 | * completed I/O. The size of the integrity buffer must be <= to the | |
314 | * size reported by bio_integrity_tag_size(). | |
315 | */ | |
316 | int bio_integrity_get_tag(struct bio *bio, void *tag_buf, unsigned int len) | |
317 | { | |
318 | BUG_ON(bio_data_dir(bio) != READ); | |
319 | ||
320 | return bio_integrity_tag(bio, tag_buf, len, 0); | |
321 | } | |
322 | EXPORT_SYMBOL(bio_integrity_get_tag); | |
323 | ||
324 | /** | |
325 | * bio_integrity_generate - Generate integrity metadata for a bio | |
326 | * @bio: bio to generate integrity metadata for | |
327 | * | |
328 | * Description: Generates integrity metadata for a bio by calling the | |
329 | * block device's generation callback function. The bio must have a | |
330 | * bip attached with enough room to accommodate the generated | |
331 | * integrity metadata. | |
332 | */ | |
333 | static void bio_integrity_generate(struct bio *bio) | |
334 | { | |
335 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); | |
336 | struct blk_integrity_exchg bix; | |
337 | struct bio_vec *bv; | |
338 | sector_t sector = bio->bi_sector; | |
339 | unsigned int i, sectors, total; | |
340 | void *prot_buf = bio->bi_integrity->bip_buf; | |
341 | ||
342 | total = 0; | |
343 | bix.disk_name = bio->bi_bdev->bd_disk->disk_name; | |
344 | bix.sector_size = bi->sector_size; | |
345 | ||
346 | bio_for_each_segment(bv, bio, i) { | |
e8e3c3d6 | 347 | void *kaddr = kmap_atomic(bv->bv_page); |
7ba1ba12 MP |
348 | bix.data_buf = kaddr + bv->bv_offset; |
349 | bix.data_size = bv->bv_len; | |
350 | bix.prot_buf = prot_buf; | |
351 | bix.sector = sector; | |
352 | ||
353 | bi->generate_fn(&bix); | |
354 | ||
355 | sectors = bv->bv_len / bi->sector_size; | |
356 | sector += sectors; | |
357 | prot_buf += sectors * bi->tuple_size; | |
358 | total += sectors * bi->tuple_size; | |
359 | BUG_ON(total > bio->bi_integrity->bip_size); | |
360 | ||
e8e3c3d6 | 361 | kunmap_atomic(kaddr); |
7ba1ba12 MP |
362 | } |
363 | } | |
364 | ||
9c02f2b0 JA |
365 | static inline unsigned short blk_integrity_tuple_size(struct blk_integrity *bi) |
366 | { | |
367 | if (bi) | |
368 | return bi->tuple_size; | |
369 | ||
370 | return 0; | |
371 | } | |
372 | ||
7ba1ba12 MP |
373 | /** |
374 | * bio_integrity_prep - Prepare bio for integrity I/O | |
375 | * @bio: bio to prepare | |
376 | * | |
377 | * Description: Allocates a buffer for integrity metadata, maps the | |
378 | * pages and attaches them to a bio. The bio must have data | |
379 | * direction, target device and start sector set priot to calling. In | |
380 | * the WRITE case, integrity metadata will be generated using the | |
381 | * block device's integrity function. In the READ case, the buffer | |
382 | * will be prepared for DMA and a suitable end_io handler set up. | |
383 | */ | |
384 | int bio_integrity_prep(struct bio *bio) | |
385 | { | |
386 | struct bio_integrity_payload *bip; | |
387 | struct blk_integrity *bi; | |
388 | struct request_queue *q; | |
389 | void *buf; | |
390 | unsigned long start, end; | |
391 | unsigned int len, nr_pages; | |
392 | unsigned int bytes, offset, i; | |
393 | unsigned int sectors; | |
394 | ||
395 | bi = bdev_get_integrity(bio->bi_bdev); | |
396 | q = bdev_get_queue(bio->bi_bdev); | |
397 | BUG_ON(bi == NULL); | |
398 | BUG_ON(bio_integrity(bio)); | |
399 | ||
400 | sectors = bio_integrity_hw_sectors(bi, bio_sectors(bio)); | |
401 | ||
402 | /* Allocate kernel buffer for protection data */ | |
403 | len = sectors * blk_integrity_tuple_size(bi); | |
72f46503 | 404 | buf = kmalloc(len, GFP_NOIO | q->bounce_gfp); |
7ba1ba12 MP |
405 | if (unlikely(buf == NULL)) { |
406 | printk(KERN_ERR "could not allocate integrity buffer\n"); | |
220eb7fd | 407 | return -ENOMEM; |
7ba1ba12 MP |
408 | } |
409 | ||
410 | end = (((unsigned long) buf) + len + PAGE_SIZE - 1) >> PAGE_SHIFT; | |
411 | start = ((unsigned long) buf) >> PAGE_SHIFT; | |
412 | nr_pages = end - start; | |
413 | ||
414 | /* Allocate bio integrity payload and integrity vectors */ | |
415 | bip = bio_integrity_alloc(bio, GFP_NOIO, nr_pages); | |
416 | if (unlikely(bip == NULL)) { | |
417 | printk(KERN_ERR "could not allocate data integrity bioset\n"); | |
418 | kfree(buf); | |
419 | return -EIO; | |
420 | } | |
421 | ||
422 | bip->bip_buf = buf; | |
423 | bip->bip_size = len; | |
424 | bip->bip_sector = bio->bi_sector; | |
425 | ||
426 | /* Map it */ | |
427 | offset = offset_in_page(buf); | |
428 | for (i = 0 ; i < nr_pages ; i++) { | |
429 | int ret; | |
430 | bytes = PAGE_SIZE - offset; | |
431 | ||
432 | if (len <= 0) | |
433 | break; | |
434 | ||
435 | if (bytes > len) | |
436 | bytes = len; | |
437 | ||
438 | ret = bio_integrity_add_page(bio, virt_to_page(buf), | |
439 | bytes, offset); | |
440 | ||
441 | if (ret == 0) | |
442 | return 0; | |
443 | ||
444 | if (ret < bytes) | |
445 | break; | |
446 | ||
447 | buf += bytes; | |
448 | len -= bytes; | |
449 | offset = 0; | |
450 | } | |
451 | ||
452 | /* Install custom I/O completion handler if read verify is enabled */ | |
453 | if (bio_data_dir(bio) == READ) { | |
454 | bip->bip_end_io = bio->bi_end_io; | |
455 | bio->bi_end_io = bio_integrity_endio; | |
456 | } | |
457 | ||
458 | /* Auto-generate integrity metadata if this is a write */ | |
459 | if (bio_data_dir(bio) == WRITE) | |
460 | bio_integrity_generate(bio); | |
461 | ||
462 | return 0; | |
463 | } | |
464 | EXPORT_SYMBOL(bio_integrity_prep); | |
465 | ||
466 | /** | |
467 | * bio_integrity_verify - Verify integrity metadata for a bio | |
468 | * @bio: bio to verify | |
469 | * | |
470 | * Description: This function is called to verify the integrity of a | |
471 | * bio. The data in the bio io_vec is compared to the integrity | |
472 | * metadata returned by the HBA. | |
473 | */ | |
474 | static int bio_integrity_verify(struct bio *bio) | |
475 | { | |
476 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); | |
477 | struct blk_integrity_exchg bix; | |
478 | struct bio_vec *bv; | |
479 | sector_t sector = bio->bi_integrity->bip_sector; | |
480 | unsigned int i, sectors, total, ret; | |
481 | void *prot_buf = bio->bi_integrity->bip_buf; | |
482 | ||
483 | ret = total = 0; | |
484 | bix.disk_name = bio->bi_bdev->bd_disk->disk_name; | |
485 | bix.sector_size = bi->sector_size; | |
486 | ||
487 | bio_for_each_segment(bv, bio, i) { | |
e8e3c3d6 | 488 | void *kaddr = kmap_atomic(bv->bv_page); |
7ba1ba12 MP |
489 | bix.data_buf = kaddr + bv->bv_offset; |
490 | bix.data_size = bv->bv_len; | |
491 | bix.prot_buf = prot_buf; | |
492 | bix.sector = sector; | |
493 | ||
494 | ret = bi->verify_fn(&bix); | |
495 | ||
496 | if (ret) { | |
e8e3c3d6 | 497 | kunmap_atomic(kaddr); |
7b24fc4d | 498 | return ret; |
7ba1ba12 MP |
499 | } |
500 | ||
501 | sectors = bv->bv_len / bi->sector_size; | |
502 | sector += sectors; | |
503 | prot_buf += sectors * bi->tuple_size; | |
504 | total += sectors * bi->tuple_size; | |
505 | BUG_ON(total > bio->bi_integrity->bip_size); | |
506 | ||
e8e3c3d6 | 507 | kunmap_atomic(kaddr); |
7ba1ba12 MP |
508 | } |
509 | ||
510 | return ret; | |
511 | } | |
512 | ||
513 | /** | |
514 | * bio_integrity_verify_fn - Integrity I/O completion worker | |
515 | * @work: Work struct stored in bio to be verified | |
516 | * | |
517 | * Description: This workqueue function is called to complete a READ | |
518 | * request. The function verifies the transferred integrity metadata | |
519 | * and then calls the original bio end_io function. | |
520 | */ | |
521 | static void bio_integrity_verify_fn(struct work_struct *work) | |
522 | { | |
b984679e | 523 | struct bio_integrity_payload *bip = |
7ba1ba12 MP |
524 | container_of(work, struct bio_integrity_payload, bip_work); |
525 | struct bio *bio = bip->bip_bio; | |
7b24fc4d | 526 | int error; |
7ba1ba12 | 527 | |
7b24fc4d | 528 | error = bio_integrity_verify(bio); |
7ba1ba12 MP |
529 | |
530 | /* Restore original bio completion handler */ | |
531 | bio->bi_end_io = bip->bip_end_io; | |
7b24fc4d | 532 | bio_endio(bio, error); |
7ba1ba12 MP |
533 | } |
534 | ||
535 | /** | |
536 | * bio_integrity_endio - Integrity I/O completion function | |
537 | * @bio: Protected bio | |
538 | * @error: Pointer to errno | |
539 | * | |
540 | * Description: Completion for integrity I/O | |
541 | * | |
542 | * Normally I/O completion is done in interrupt context. However, | |
543 | * verifying I/O integrity is a time-consuming task which must be run | |
544 | * in process context. This function postpones completion | |
545 | * accordingly. | |
546 | */ | |
547 | void bio_integrity_endio(struct bio *bio, int error) | |
548 | { | |
549 | struct bio_integrity_payload *bip = bio->bi_integrity; | |
550 | ||
551 | BUG_ON(bip->bip_bio != bio); | |
552 | ||
7b24fc4d MP |
553 | /* In case of an I/O error there is no point in verifying the |
554 | * integrity metadata. Restore original bio end_io handler | |
555 | * and run it. | |
556 | */ | |
557 | if (error) { | |
558 | bio->bi_end_io = bip->bip_end_io; | |
559 | bio_endio(bio, error); | |
560 | ||
561 | return; | |
562 | } | |
563 | ||
7ba1ba12 MP |
564 | INIT_WORK(&bip->bip_work, bio_integrity_verify_fn); |
565 | queue_work(kintegrityd_wq, &bip->bip_work); | |
566 | } | |
567 | EXPORT_SYMBOL(bio_integrity_endio); | |
568 | ||
569 | /** | |
570 | * bio_integrity_mark_head - Advance bip_vec skip bytes | |
571 | * @bip: Integrity vector to advance | |
572 | * @skip: Number of bytes to advance it | |
573 | */ | |
b984679e JA |
574 | void bio_integrity_mark_head(struct bio_integrity_payload *bip, |
575 | unsigned int skip) | |
7ba1ba12 MP |
576 | { |
577 | struct bio_vec *iv; | |
578 | unsigned int i; | |
579 | ||
580 | bip_for_each_vec(iv, bip, i) { | |
581 | if (skip == 0) { | |
582 | bip->bip_idx = i; | |
583 | return; | |
584 | } else if (skip >= iv->bv_len) { | |
585 | skip -= iv->bv_len; | |
586 | } else { /* skip < iv->bv_len) */ | |
587 | iv->bv_offset += skip; | |
588 | iv->bv_len -= skip; | |
589 | bip->bip_idx = i; | |
590 | return; | |
591 | } | |
592 | } | |
593 | } | |
594 | ||
595 | /** | |
596 | * bio_integrity_mark_tail - Truncate bip_vec to be len bytes long | |
597 | * @bip: Integrity vector to truncate | |
598 | * @len: New length of integrity vector | |
599 | */ | |
b984679e JA |
600 | void bio_integrity_mark_tail(struct bio_integrity_payload *bip, |
601 | unsigned int len) | |
7ba1ba12 MP |
602 | { |
603 | struct bio_vec *iv; | |
604 | unsigned int i; | |
605 | ||
606 | bip_for_each_vec(iv, bip, i) { | |
607 | if (len == 0) { | |
608 | bip->bip_vcnt = i; | |
609 | return; | |
610 | } else if (len >= iv->bv_len) { | |
611 | len -= iv->bv_len; | |
612 | } else { /* len < iv->bv_len) */ | |
613 | iv->bv_len = len; | |
614 | len = 0; | |
615 | } | |
616 | } | |
617 | } | |
618 | ||
619 | /** | |
620 | * bio_integrity_advance - Advance integrity vector | |
621 | * @bio: bio whose integrity vector to update | |
622 | * @bytes_done: number of data bytes that have been completed | |
623 | * | |
624 | * Description: This function calculates how many integrity bytes the | |
625 | * number of completed data bytes correspond to and advances the | |
626 | * integrity vector accordingly. | |
627 | */ | |
628 | void bio_integrity_advance(struct bio *bio, unsigned int bytes_done) | |
629 | { | |
630 | struct bio_integrity_payload *bip = bio->bi_integrity; | |
631 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); | |
632 | unsigned int nr_sectors; | |
633 | ||
634 | BUG_ON(bip == NULL); | |
635 | BUG_ON(bi == NULL); | |
636 | ||
637 | nr_sectors = bio_integrity_hw_sectors(bi, bytes_done >> 9); | |
638 | bio_integrity_mark_head(bip, nr_sectors * bi->tuple_size); | |
639 | } | |
640 | EXPORT_SYMBOL(bio_integrity_advance); | |
641 | ||
642 | /** | |
643 | * bio_integrity_trim - Trim integrity vector | |
644 | * @bio: bio whose integrity vector to update | |
645 | * @offset: offset to first data sector | |
646 | * @sectors: number of data sectors | |
647 | * | |
648 | * Description: Used to trim the integrity vector in a cloned bio. | |
649 | * The ivec will be advanced corresponding to 'offset' data sectors | |
650 | * and the length will be truncated corresponding to 'len' data | |
651 | * sectors. | |
652 | */ | |
b984679e JA |
653 | void bio_integrity_trim(struct bio *bio, unsigned int offset, |
654 | unsigned int sectors) | |
7ba1ba12 MP |
655 | { |
656 | struct bio_integrity_payload *bip = bio->bi_integrity; | |
657 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); | |
658 | unsigned int nr_sectors; | |
659 | ||
660 | BUG_ON(bip == NULL); | |
661 | BUG_ON(bi == NULL); | |
662 | BUG_ON(!bio_flagged(bio, BIO_CLONED)); | |
663 | ||
664 | nr_sectors = bio_integrity_hw_sectors(bi, sectors); | |
665 | bip->bip_sector = bip->bip_sector + offset; | |
666 | bio_integrity_mark_head(bip, offset * bi->tuple_size); | |
667 | bio_integrity_mark_tail(bip, sectors * bi->tuple_size); | |
668 | } | |
669 | EXPORT_SYMBOL(bio_integrity_trim); | |
670 | ||
671 | /** | |
672 | * bio_integrity_split - Split integrity metadata | |
673 | * @bio: Protected bio | |
674 | * @bp: Resulting bio_pair | |
675 | * @sectors: Offset | |
676 | * | |
677 | * Description: Splits an integrity page into a bio_pair. | |
678 | */ | |
679 | void bio_integrity_split(struct bio *bio, struct bio_pair *bp, int sectors) | |
680 | { | |
681 | struct blk_integrity *bi; | |
682 | struct bio_integrity_payload *bip = bio->bi_integrity; | |
683 | unsigned int nr_sectors; | |
684 | ||
685 | if (bio_integrity(bio) == 0) | |
686 | return; | |
687 | ||
688 | bi = bdev_get_integrity(bio->bi_bdev); | |
689 | BUG_ON(bi == NULL); | |
690 | BUG_ON(bip->bip_vcnt != 1); | |
691 | ||
692 | nr_sectors = bio_integrity_hw_sectors(bi, sectors); | |
693 | ||
694 | bp->bio1.bi_integrity = &bp->bip1; | |
695 | bp->bio2.bi_integrity = &bp->bip2; | |
696 | ||
697 | bp->iv1 = bip->bip_vec[0]; | |
698 | bp->iv2 = bip->bip_vec[0]; | |
699 | ||
7878cba9 MP |
700 | bp->bip1.bip_vec[0] = bp->iv1; |
701 | bp->bip2.bip_vec[0] = bp->iv2; | |
7ba1ba12 MP |
702 | |
703 | bp->iv1.bv_len = sectors * bi->tuple_size; | |
704 | bp->iv2.bv_offset += sectors * bi->tuple_size; | |
705 | bp->iv2.bv_len -= sectors * bi->tuple_size; | |
706 | ||
707 | bp->bip1.bip_sector = bio->bi_integrity->bip_sector; | |
708 | bp->bip2.bip_sector = bio->bi_integrity->bip_sector + nr_sectors; | |
709 | ||
710 | bp->bip1.bip_vcnt = bp->bip2.bip_vcnt = 1; | |
711 | bp->bip1.bip_idx = bp->bip2.bip_idx = 0; | |
712 | } | |
713 | EXPORT_SYMBOL(bio_integrity_split); | |
714 | ||
715 | /** | |
716 | * bio_integrity_clone - Callback for cloning bios with integrity metadata | |
717 | * @bio: New bio | |
718 | * @bio_src: Original bio | |
87092698 | 719 | * @gfp_mask: Memory allocation mask |
7ba1ba12 MP |
720 | * |
721 | * Description: Called to allocate a bip when cloning a bio | |
722 | */ | |
7878cba9 | 723 | int bio_integrity_clone(struct bio *bio, struct bio *bio_src, |
1e2a410f | 724 | gfp_t gfp_mask) |
7ba1ba12 MP |
725 | { |
726 | struct bio_integrity_payload *bip_src = bio_src->bi_integrity; | |
727 | struct bio_integrity_payload *bip; | |
728 | ||
729 | BUG_ON(bip_src == NULL); | |
730 | ||
1e2a410f | 731 | bip = bio_integrity_alloc(bio, gfp_mask, bip_src->bip_vcnt); |
7ba1ba12 MP |
732 | |
733 | if (bip == NULL) | |
734 | return -EIO; | |
735 | ||
736 | memcpy(bip->bip_vec, bip_src->bip_vec, | |
737 | bip_src->bip_vcnt * sizeof(struct bio_vec)); | |
738 | ||
739 | bip->bip_sector = bip_src->bip_sector; | |
740 | bip->bip_vcnt = bip_src->bip_vcnt; | |
741 | bip->bip_idx = bip_src->bip_idx; | |
742 | ||
743 | return 0; | |
744 | } | |
745 | EXPORT_SYMBOL(bio_integrity_clone); | |
746 | ||
7878cba9 | 747 | int bioset_integrity_create(struct bio_set *bs, int pool_size) |
7ba1ba12 | 748 | { |
7878cba9 MP |
749 | unsigned int max_slab = vecs_to_idx(BIO_MAX_PAGES); |
750 | ||
a91a2785 MP |
751 | if (bs->bio_integrity_pool) |
752 | return 0; | |
753 | ||
7878cba9 MP |
754 | bs->bio_integrity_pool = |
755 | mempool_create_slab_pool(pool_size, bip_slab[max_slab].slab); | |
7ba1ba12 | 756 | |
7878cba9 MP |
757 | if (!bs->bio_integrity_pool) |
758 | return -1; | |
759 | ||
760 | return 0; | |
761 | } | |
762 | EXPORT_SYMBOL(bioset_integrity_create); | |
763 | ||
764 | void bioset_integrity_free(struct bio_set *bs) | |
765 | { | |
766 | if (bs->bio_integrity_pool) | |
767 | mempool_destroy(bs->bio_integrity_pool); | |
768 | } | |
769 | EXPORT_SYMBOL(bioset_integrity_free); | |
770 | ||
771 | void __init bio_integrity_init(void) | |
772 | { | |
773 | unsigned int i; | |
774 | ||
a6e8dc46 TH |
775 | /* |
776 | * kintegrityd won't block much but may burn a lot of CPU cycles. | |
777 | * Make it highpri CPU intensive wq with max concurrency of 1. | |
778 | */ | |
779 | kintegrityd_wq = alloc_workqueue("kintegrityd", WQ_MEM_RECLAIM | | |
780 | WQ_HIGHPRI | WQ_CPU_INTENSIVE, 1); | |
6d2a78e7 MP |
781 | if (!kintegrityd_wq) |
782 | panic("Failed to create kintegrityd\n"); | |
7ba1ba12 | 783 | |
7878cba9 MP |
784 | for (i = 0 ; i < BIOVEC_NR_POOLS ; i++) { |
785 | unsigned int size; | |
7ba1ba12 | 786 | |
7878cba9 MP |
787 | size = sizeof(struct bio_integrity_payload) |
788 | + bip_slab[i].nr_vecs * sizeof(struct bio_vec); | |
7ba1ba12 | 789 | |
7878cba9 MP |
790 | bip_slab[i].slab = |
791 | kmem_cache_create(bip_slab[i].name, size, 0, | |
792 | SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); | |
793 | } | |
7ba1ba12 | 794 | } |