Martin K. Petersen | 7ba1ba1 | 2008-06-30 20:04:41 +0200 | [diff] [blame] | 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 | |
| 23 | #include <linux/blkdev.h> |
| 24 | #include <linux/mempool.h> |
| 25 | #include <linux/bio.h> |
| 26 | #include <linux/workqueue.h> |
| 27 | |
| 28 | static struct kmem_cache *bio_integrity_slab __read_mostly; |
| 29 | static struct workqueue_struct *kintegrityd_wq; |
| 30 | |
| 31 | /** |
| 32 | * bio_integrity_alloc_bioset - Allocate integrity payload and attach it to bio |
| 33 | * @bio: bio to attach integrity metadata to |
| 34 | * @gfp_mask: Memory allocation mask |
| 35 | * @nr_vecs: Number of integrity metadata scatter-gather elements |
| 36 | * @bs: bio_set to allocate from |
| 37 | * |
| 38 | * Description: This function prepares a bio for attaching integrity |
| 39 | * metadata. nr_vecs specifies the maximum number of pages containing |
| 40 | * integrity metadata that can be attached. |
| 41 | */ |
Jens Axboe | b984679 | 2008-06-17 19:05:48 +0200 | [diff] [blame] | 42 | struct bio_integrity_payload *bio_integrity_alloc_bioset(struct bio *bio, |
| 43 | gfp_t gfp_mask, |
| 44 | unsigned int nr_vecs, |
| 45 | struct bio_set *bs) |
Martin K. Petersen | 7ba1ba1 | 2008-06-30 20:04:41 +0200 | [diff] [blame] | 46 | { |
| 47 | struct bio_integrity_payload *bip; |
| 48 | struct bio_vec *iv; |
| 49 | unsigned long idx; |
| 50 | |
| 51 | BUG_ON(bio == NULL); |
| 52 | |
| 53 | bip = mempool_alloc(bs->bio_integrity_pool, gfp_mask); |
| 54 | if (unlikely(bip == NULL)) { |
| 55 | printk(KERN_ERR "%s: could not alloc bip\n", __func__); |
| 56 | return NULL; |
| 57 | } |
| 58 | |
| 59 | memset(bip, 0, sizeof(*bip)); |
| 60 | |
| 61 | iv = bvec_alloc_bs(gfp_mask, nr_vecs, &idx, bs); |
| 62 | if (unlikely(iv == NULL)) { |
| 63 | printk(KERN_ERR "%s: could not alloc bip_vec\n", __func__); |
| 64 | mempool_free(bip, bs->bio_integrity_pool); |
| 65 | return NULL; |
| 66 | } |
| 67 | |
| 68 | bip->bip_pool = idx; |
| 69 | bip->bip_vec = iv; |
| 70 | bip->bip_bio = bio; |
| 71 | bio->bi_integrity = bip; |
| 72 | |
| 73 | return bip; |
| 74 | } |
| 75 | EXPORT_SYMBOL(bio_integrity_alloc_bioset); |
| 76 | |
| 77 | /** |
| 78 | * bio_integrity_alloc - Allocate integrity payload and attach it to bio |
| 79 | * @bio: bio to attach integrity metadata to |
| 80 | * @gfp_mask: Memory allocation mask |
| 81 | * @nr_vecs: Number of integrity metadata scatter-gather elements |
| 82 | * |
| 83 | * Description: This function prepares a bio for attaching integrity |
| 84 | * metadata. nr_vecs specifies the maximum number of pages containing |
| 85 | * integrity metadata that can be attached. |
| 86 | */ |
Jens Axboe | b984679 | 2008-06-17 19:05:48 +0200 | [diff] [blame] | 87 | struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio, |
| 88 | gfp_t gfp_mask, |
| 89 | unsigned int nr_vecs) |
Martin K. Petersen | 7ba1ba1 | 2008-06-30 20:04:41 +0200 | [diff] [blame] | 90 | { |
| 91 | return bio_integrity_alloc_bioset(bio, gfp_mask, nr_vecs, fs_bio_set); |
| 92 | } |
| 93 | EXPORT_SYMBOL(bio_integrity_alloc); |
| 94 | |
| 95 | /** |
| 96 | * bio_integrity_free - Free bio integrity payload |
| 97 | * @bio: bio containing bip to be freed |
| 98 | * @bs: bio_set this bio was allocated from |
| 99 | * |
| 100 | * Description: Used to free the integrity portion of a bio. Usually |
| 101 | * called from bio_free(). |
| 102 | */ |
| 103 | void bio_integrity_free(struct bio *bio, struct bio_set *bs) |
| 104 | { |
| 105 | struct bio_integrity_payload *bip = bio->bi_integrity; |
| 106 | |
| 107 | BUG_ON(bip == NULL); |
| 108 | |
| 109 | /* A cloned bio doesn't own the integrity metadata */ |
| 110 | if (!bio_flagged(bio, BIO_CLONED) && bip->bip_buf != NULL) |
| 111 | kfree(bip->bip_buf); |
| 112 | |
| 113 | mempool_free(bip->bip_vec, bs->bvec_pools[bip->bip_pool]); |
| 114 | mempool_free(bip, bs->bio_integrity_pool); |
| 115 | |
| 116 | bio->bi_integrity = NULL; |
| 117 | } |
| 118 | EXPORT_SYMBOL(bio_integrity_free); |
| 119 | |
| 120 | /** |
| 121 | * bio_integrity_add_page - Attach integrity metadata |
| 122 | * @bio: bio to update |
| 123 | * @page: page containing integrity metadata |
| 124 | * @len: number of bytes of integrity metadata in page |
| 125 | * @offset: start offset within page |
| 126 | * |
| 127 | * Description: Attach a page containing integrity metadata to bio. |
| 128 | */ |
| 129 | int bio_integrity_add_page(struct bio *bio, struct page *page, |
| 130 | unsigned int len, unsigned int offset) |
| 131 | { |
| 132 | struct bio_integrity_payload *bip = bio->bi_integrity; |
| 133 | struct bio_vec *iv; |
| 134 | |
| 135 | if (bip->bip_vcnt >= bvec_nr_vecs(bip->bip_pool)) { |
| 136 | printk(KERN_ERR "%s: bip_vec full\n", __func__); |
| 137 | return 0; |
| 138 | } |
| 139 | |
| 140 | iv = bip_vec_idx(bip, bip->bip_vcnt); |
| 141 | BUG_ON(iv == NULL); |
| 142 | BUG_ON(iv->bv_page != NULL); |
| 143 | |
| 144 | iv->bv_page = page; |
| 145 | iv->bv_len = len; |
| 146 | iv->bv_offset = offset; |
| 147 | bip->bip_vcnt++; |
| 148 | |
| 149 | return len; |
| 150 | } |
| 151 | EXPORT_SYMBOL(bio_integrity_add_page); |
| 152 | |
Jens Axboe | 9c02f2b | 2008-09-18 09:31:53 -0700 | [diff] [blame^] | 153 | static struct blk_integrity *bdev_get_integrity(struct block_device *bdev) |
| 154 | { |
| 155 | return bdev->bd_disk->integrity; |
| 156 | } |
| 157 | |
| 158 | static int bdev_integrity_enabled(struct block_device *bdev, int rw) |
| 159 | { |
| 160 | struct blk_integrity *bi = bdev_get_integrity(bdev); |
| 161 | |
| 162 | if (bi == NULL) |
| 163 | return 0; |
| 164 | |
| 165 | if (rw == READ && bi->verify_fn != NULL && |
| 166 | (bi->flags & INTEGRITY_FLAG_READ)) |
| 167 | return 1; |
| 168 | |
| 169 | if (rw == WRITE && bi->generate_fn != NULL && |
| 170 | (bi->flags & INTEGRITY_FLAG_WRITE)) |
| 171 | return 1; |
| 172 | |
| 173 | return 0; |
| 174 | } |
| 175 | |
Martin K. Petersen | 7ba1ba1 | 2008-06-30 20:04:41 +0200 | [diff] [blame] | 176 | /** |
| 177 | * bio_integrity_enabled - Check whether integrity can be passed |
| 178 | * @bio: bio to check |
| 179 | * |
| 180 | * Description: Determines whether bio_integrity_prep() can be called |
| 181 | * on this bio or not. bio data direction and target device must be |
| 182 | * set prior to calling. The functions honors the write_generate and |
| 183 | * read_verify flags in sysfs. |
| 184 | */ |
| 185 | int bio_integrity_enabled(struct bio *bio) |
| 186 | { |
| 187 | /* Already protected? */ |
| 188 | if (bio_integrity(bio)) |
| 189 | return 0; |
| 190 | |
| 191 | return bdev_integrity_enabled(bio->bi_bdev, bio_data_dir(bio)); |
| 192 | } |
| 193 | EXPORT_SYMBOL(bio_integrity_enabled); |
| 194 | |
| 195 | /** |
| 196 | * bio_integrity_hw_sectors - Convert 512b sectors to hardware ditto |
| 197 | * @bi: blk_integrity profile for device |
| 198 | * @sectors: Number of 512 sectors to convert |
| 199 | * |
| 200 | * Description: The block layer calculates everything in 512 byte |
| 201 | * sectors but integrity metadata is done in terms of the hardware |
| 202 | * sector size of the storage device. Convert the block layer sectors |
| 203 | * to physical sectors. |
| 204 | */ |
Jens Axboe | b984679 | 2008-06-17 19:05:48 +0200 | [diff] [blame] | 205 | static inline unsigned int bio_integrity_hw_sectors(struct blk_integrity *bi, |
| 206 | unsigned int sectors) |
Martin K. Petersen | 7ba1ba1 | 2008-06-30 20:04:41 +0200 | [diff] [blame] | 207 | { |
| 208 | /* At this point there are only 512b or 4096b DIF/EPP devices */ |
| 209 | if (bi->sector_size == 4096) |
| 210 | return sectors >>= 3; |
| 211 | |
| 212 | return sectors; |
| 213 | } |
| 214 | |
| 215 | /** |
| 216 | * bio_integrity_tag_size - Retrieve integrity tag space |
| 217 | * @bio: bio to inspect |
| 218 | * |
| 219 | * Description: Returns the maximum number of tag bytes that can be |
| 220 | * attached to this bio. Filesystems can use this to determine how |
| 221 | * much metadata to attach to an I/O. |
| 222 | */ |
| 223 | unsigned int bio_integrity_tag_size(struct bio *bio) |
| 224 | { |
| 225 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); |
| 226 | |
| 227 | BUG_ON(bio->bi_size == 0); |
| 228 | |
| 229 | return bi->tag_size * (bio->bi_size / bi->sector_size); |
| 230 | } |
| 231 | EXPORT_SYMBOL(bio_integrity_tag_size); |
| 232 | |
| 233 | int bio_integrity_tag(struct bio *bio, void *tag_buf, unsigned int len, int set) |
| 234 | { |
| 235 | struct bio_integrity_payload *bip = bio->bi_integrity; |
| 236 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); |
| 237 | unsigned int nr_sectors; |
| 238 | |
| 239 | BUG_ON(bip->bip_buf == NULL); |
| 240 | |
| 241 | if (bi->tag_size == 0) |
| 242 | return -1; |
| 243 | |
Jens Axboe | b984679 | 2008-06-17 19:05:48 +0200 | [diff] [blame] | 244 | nr_sectors = bio_integrity_hw_sectors(bi, |
| 245 | DIV_ROUND_UP(len, bi->tag_size)); |
Martin K. Petersen | 7ba1ba1 | 2008-06-30 20:04:41 +0200 | [diff] [blame] | 246 | |
| 247 | if (nr_sectors * bi->tuple_size > bip->bip_size) { |
| 248 | printk(KERN_ERR "%s: tag too big for bio: %u > %u\n", |
| 249 | __func__, nr_sectors * bi->tuple_size, bip->bip_size); |
| 250 | return -1; |
| 251 | } |
| 252 | |
| 253 | if (set) |
| 254 | bi->set_tag_fn(bip->bip_buf, tag_buf, nr_sectors); |
| 255 | else |
| 256 | bi->get_tag_fn(bip->bip_buf, tag_buf, nr_sectors); |
| 257 | |
| 258 | return 0; |
| 259 | } |
| 260 | |
| 261 | /** |
| 262 | * bio_integrity_set_tag - Attach a tag buffer to a bio |
| 263 | * @bio: bio to attach buffer to |
| 264 | * @tag_buf: Pointer to a buffer containing tag data |
| 265 | * @len: Length of the included buffer |
| 266 | * |
| 267 | * Description: Use this function to tag a bio by leveraging the extra |
| 268 | * space provided by devices formatted with integrity protection. The |
| 269 | * size of the integrity buffer must be <= to the size reported by |
| 270 | * bio_integrity_tag_size(). |
| 271 | */ |
| 272 | int bio_integrity_set_tag(struct bio *bio, void *tag_buf, unsigned int len) |
| 273 | { |
| 274 | BUG_ON(bio_data_dir(bio) != WRITE); |
| 275 | |
| 276 | return bio_integrity_tag(bio, tag_buf, len, 1); |
| 277 | } |
| 278 | EXPORT_SYMBOL(bio_integrity_set_tag); |
| 279 | |
| 280 | /** |
| 281 | * bio_integrity_get_tag - Retrieve a tag buffer from a bio |
| 282 | * @bio: bio to retrieve buffer from |
| 283 | * @tag_buf: Pointer to a buffer for the tag data |
| 284 | * @len: Length of the target buffer |
| 285 | * |
| 286 | * Description: Use this function to retrieve the tag buffer from a |
| 287 | * completed I/O. The size of the integrity buffer must be <= to the |
| 288 | * size reported by bio_integrity_tag_size(). |
| 289 | */ |
| 290 | int bio_integrity_get_tag(struct bio *bio, void *tag_buf, unsigned int len) |
| 291 | { |
| 292 | BUG_ON(bio_data_dir(bio) != READ); |
| 293 | |
| 294 | return bio_integrity_tag(bio, tag_buf, len, 0); |
| 295 | } |
| 296 | EXPORT_SYMBOL(bio_integrity_get_tag); |
| 297 | |
| 298 | /** |
| 299 | * bio_integrity_generate - Generate integrity metadata for a bio |
| 300 | * @bio: bio to generate integrity metadata for |
| 301 | * |
| 302 | * Description: Generates integrity metadata for a bio by calling the |
| 303 | * block device's generation callback function. The bio must have a |
| 304 | * bip attached with enough room to accommodate the generated |
| 305 | * integrity metadata. |
| 306 | */ |
| 307 | static void bio_integrity_generate(struct bio *bio) |
| 308 | { |
| 309 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); |
| 310 | struct blk_integrity_exchg bix; |
| 311 | struct bio_vec *bv; |
| 312 | sector_t sector = bio->bi_sector; |
| 313 | unsigned int i, sectors, total; |
| 314 | void *prot_buf = bio->bi_integrity->bip_buf; |
| 315 | |
| 316 | total = 0; |
| 317 | bix.disk_name = bio->bi_bdev->bd_disk->disk_name; |
| 318 | bix.sector_size = bi->sector_size; |
| 319 | |
| 320 | bio_for_each_segment(bv, bio, i) { |
| 321 | void *kaddr = kmap_atomic(bv->bv_page, KM_USER0); |
| 322 | bix.data_buf = kaddr + bv->bv_offset; |
| 323 | bix.data_size = bv->bv_len; |
| 324 | bix.prot_buf = prot_buf; |
| 325 | bix.sector = sector; |
| 326 | |
| 327 | bi->generate_fn(&bix); |
| 328 | |
| 329 | sectors = bv->bv_len / bi->sector_size; |
| 330 | sector += sectors; |
| 331 | prot_buf += sectors * bi->tuple_size; |
| 332 | total += sectors * bi->tuple_size; |
| 333 | BUG_ON(total > bio->bi_integrity->bip_size); |
| 334 | |
| 335 | kunmap_atomic(kaddr, KM_USER0); |
| 336 | } |
| 337 | } |
| 338 | |
Jens Axboe | 9c02f2b | 2008-09-18 09:31:53 -0700 | [diff] [blame^] | 339 | static inline unsigned short blk_integrity_tuple_size(struct blk_integrity *bi) |
| 340 | { |
| 341 | if (bi) |
| 342 | return bi->tuple_size; |
| 343 | |
| 344 | return 0; |
| 345 | } |
| 346 | |
Martin K. Petersen | 7ba1ba1 | 2008-06-30 20:04:41 +0200 | [diff] [blame] | 347 | /** |
| 348 | * bio_integrity_prep - Prepare bio for integrity I/O |
| 349 | * @bio: bio to prepare |
| 350 | * |
| 351 | * Description: Allocates a buffer for integrity metadata, maps the |
| 352 | * pages and attaches them to a bio. The bio must have data |
| 353 | * direction, target device and start sector set priot to calling. In |
| 354 | * the WRITE case, integrity metadata will be generated using the |
| 355 | * block device's integrity function. In the READ case, the buffer |
| 356 | * will be prepared for DMA and a suitable end_io handler set up. |
| 357 | */ |
| 358 | int bio_integrity_prep(struct bio *bio) |
| 359 | { |
| 360 | struct bio_integrity_payload *bip; |
| 361 | struct blk_integrity *bi; |
| 362 | struct request_queue *q; |
| 363 | void *buf; |
| 364 | unsigned long start, end; |
| 365 | unsigned int len, nr_pages; |
| 366 | unsigned int bytes, offset, i; |
| 367 | unsigned int sectors; |
| 368 | |
| 369 | bi = bdev_get_integrity(bio->bi_bdev); |
| 370 | q = bdev_get_queue(bio->bi_bdev); |
| 371 | BUG_ON(bi == NULL); |
| 372 | BUG_ON(bio_integrity(bio)); |
| 373 | |
| 374 | sectors = bio_integrity_hw_sectors(bi, bio_sectors(bio)); |
| 375 | |
| 376 | /* Allocate kernel buffer for protection data */ |
| 377 | len = sectors * blk_integrity_tuple_size(bi); |
| 378 | buf = kmalloc(len, GFP_NOIO | __GFP_NOFAIL | q->bounce_gfp); |
| 379 | if (unlikely(buf == NULL)) { |
| 380 | printk(KERN_ERR "could not allocate integrity buffer\n"); |
| 381 | return -EIO; |
| 382 | } |
| 383 | |
| 384 | end = (((unsigned long) buf) + len + PAGE_SIZE - 1) >> PAGE_SHIFT; |
| 385 | start = ((unsigned long) buf) >> PAGE_SHIFT; |
| 386 | nr_pages = end - start; |
| 387 | |
| 388 | /* Allocate bio integrity payload and integrity vectors */ |
| 389 | bip = bio_integrity_alloc(bio, GFP_NOIO, nr_pages); |
| 390 | if (unlikely(bip == NULL)) { |
| 391 | printk(KERN_ERR "could not allocate data integrity bioset\n"); |
| 392 | kfree(buf); |
| 393 | return -EIO; |
| 394 | } |
| 395 | |
| 396 | bip->bip_buf = buf; |
| 397 | bip->bip_size = len; |
| 398 | bip->bip_sector = bio->bi_sector; |
| 399 | |
| 400 | /* Map it */ |
| 401 | offset = offset_in_page(buf); |
| 402 | for (i = 0 ; i < nr_pages ; i++) { |
| 403 | int ret; |
| 404 | bytes = PAGE_SIZE - offset; |
| 405 | |
| 406 | if (len <= 0) |
| 407 | break; |
| 408 | |
| 409 | if (bytes > len) |
| 410 | bytes = len; |
| 411 | |
| 412 | ret = bio_integrity_add_page(bio, virt_to_page(buf), |
| 413 | bytes, offset); |
| 414 | |
| 415 | if (ret == 0) |
| 416 | return 0; |
| 417 | |
| 418 | if (ret < bytes) |
| 419 | break; |
| 420 | |
| 421 | buf += bytes; |
| 422 | len -= bytes; |
| 423 | offset = 0; |
| 424 | } |
| 425 | |
| 426 | /* Install custom I/O completion handler if read verify is enabled */ |
| 427 | if (bio_data_dir(bio) == READ) { |
| 428 | bip->bip_end_io = bio->bi_end_io; |
| 429 | bio->bi_end_io = bio_integrity_endio; |
| 430 | } |
| 431 | |
| 432 | /* Auto-generate integrity metadata if this is a write */ |
| 433 | if (bio_data_dir(bio) == WRITE) |
| 434 | bio_integrity_generate(bio); |
| 435 | |
| 436 | return 0; |
| 437 | } |
| 438 | EXPORT_SYMBOL(bio_integrity_prep); |
| 439 | |
| 440 | /** |
| 441 | * bio_integrity_verify - Verify integrity metadata for a bio |
| 442 | * @bio: bio to verify |
| 443 | * |
| 444 | * Description: This function is called to verify the integrity of a |
| 445 | * bio. The data in the bio io_vec is compared to the integrity |
| 446 | * metadata returned by the HBA. |
| 447 | */ |
| 448 | static int bio_integrity_verify(struct bio *bio) |
| 449 | { |
| 450 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); |
| 451 | struct blk_integrity_exchg bix; |
| 452 | struct bio_vec *bv; |
| 453 | sector_t sector = bio->bi_integrity->bip_sector; |
| 454 | unsigned int i, sectors, total, ret; |
| 455 | void *prot_buf = bio->bi_integrity->bip_buf; |
| 456 | |
| 457 | ret = total = 0; |
| 458 | bix.disk_name = bio->bi_bdev->bd_disk->disk_name; |
| 459 | bix.sector_size = bi->sector_size; |
| 460 | |
| 461 | bio_for_each_segment(bv, bio, i) { |
| 462 | void *kaddr = kmap_atomic(bv->bv_page, KM_USER0); |
| 463 | bix.data_buf = kaddr + bv->bv_offset; |
| 464 | bix.data_size = bv->bv_len; |
| 465 | bix.prot_buf = prot_buf; |
| 466 | bix.sector = sector; |
| 467 | |
| 468 | ret = bi->verify_fn(&bix); |
| 469 | |
| 470 | if (ret) { |
| 471 | kunmap_atomic(kaddr, KM_USER0); |
| 472 | break; |
| 473 | } |
| 474 | |
| 475 | sectors = bv->bv_len / bi->sector_size; |
| 476 | sector += sectors; |
| 477 | prot_buf += sectors * bi->tuple_size; |
| 478 | total += sectors * bi->tuple_size; |
| 479 | BUG_ON(total > bio->bi_integrity->bip_size); |
| 480 | |
| 481 | kunmap_atomic(kaddr, KM_USER0); |
| 482 | } |
| 483 | |
| 484 | return ret; |
| 485 | } |
| 486 | |
| 487 | /** |
| 488 | * bio_integrity_verify_fn - Integrity I/O completion worker |
| 489 | * @work: Work struct stored in bio to be verified |
| 490 | * |
| 491 | * Description: This workqueue function is called to complete a READ |
| 492 | * request. The function verifies the transferred integrity metadata |
| 493 | * and then calls the original bio end_io function. |
| 494 | */ |
| 495 | static void bio_integrity_verify_fn(struct work_struct *work) |
| 496 | { |
Jens Axboe | b984679 | 2008-06-17 19:05:48 +0200 | [diff] [blame] | 497 | struct bio_integrity_payload *bip = |
Martin K. Petersen | 7ba1ba1 | 2008-06-30 20:04:41 +0200 | [diff] [blame] | 498 | container_of(work, struct bio_integrity_payload, bip_work); |
| 499 | struct bio *bio = bip->bip_bio; |
| 500 | int error = bip->bip_error; |
| 501 | |
| 502 | if (bio_integrity_verify(bio)) { |
| 503 | clear_bit(BIO_UPTODATE, &bio->bi_flags); |
| 504 | error = -EIO; |
| 505 | } |
| 506 | |
| 507 | /* Restore original bio completion handler */ |
| 508 | bio->bi_end_io = bip->bip_end_io; |
| 509 | |
| 510 | if (bio->bi_end_io) |
| 511 | bio->bi_end_io(bio, error); |
| 512 | } |
| 513 | |
| 514 | /** |
| 515 | * bio_integrity_endio - Integrity I/O completion function |
| 516 | * @bio: Protected bio |
| 517 | * @error: Pointer to errno |
| 518 | * |
| 519 | * Description: Completion for integrity I/O |
| 520 | * |
| 521 | * Normally I/O completion is done in interrupt context. However, |
| 522 | * verifying I/O integrity is a time-consuming task which must be run |
| 523 | * in process context. This function postpones completion |
| 524 | * accordingly. |
| 525 | */ |
| 526 | void bio_integrity_endio(struct bio *bio, int error) |
| 527 | { |
| 528 | struct bio_integrity_payload *bip = bio->bi_integrity; |
| 529 | |
| 530 | BUG_ON(bip->bip_bio != bio); |
| 531 | |
| 532 | bip->bip_error = error; |
| 533 | INIT_WORK(&bip->bip_work, bio_integrity_verify_fn); |
| 534 | queue_work(kintegrityd_wq, &bip->bip_work); |
| 535 | } |
| 536 | EXPORT_SYMBOL(bio_integrity_endio); |
| 537 | |
| 538 | /** |
| 539 | * bio_integrity_mark_head - Advance bip_vec skip bytes |
| 540 | * @bip: Integrity vector to advance |
| 541 | * @skip: Number of bytes to advance it |
| 542 | */ |
Jens Axboe | b984679 | 2008-06-17 19:05:48 +0200 | [diff] [blame] | 543 | void bio_integrity_mark_head(struct bio_integrity_payload *bip, |
| 544 | unsigned int skip) |
Martin K. Petersen | 7ba1ba1 | 2008-06-30 20:04:41 +0200 | [diff] [blame] | 545 | { |
| 546 | struct bio_vec *iv; |
| 547 | unsigned int i; |
| 548 | |
| 549 | bip_for_each_vec(iv, bip, i) { |
| 550 | if (skip == 0) { |
| 551 | bip->bip_idx = i; |
| 552 | return; |
| 553 | } else if (skip >= iv->bv_len) { |
| 554 | skip -= iv->bv_len; |
| 555 | } else { /* skip < iv->bv_len) */ |
| 556 | iv->bv_offset += skip; |
| 557 | iv->bv_len -= skip; |
| 558 | bip->bip_idx = i; |
| 559 | return; |
| 560 | } |
| 561 | } |
| 562 | } |
| 563 | |
| 564 | /** |
| 565 | * bio_integrity_mark_tail - Truncate bip_vec to be len bytes long |
| 566 | * @bip: Integrity vector to truncate |
| 567 | * @len: New length of integrity vector |
| 568 | */ |
Jens Axboe | b984679 | 2008-06-17 19:05:48 +0200 | [diff] [blame] | 569 | void bio_integrity_mark_tail(struct bio_integrity_payload *bip, |
| 570 | unsigned int len) |
Martin K. Petersen | 7ba1ba1 | 2008-06-30 20:04:41 +0200 | [diff] [blame] | 571 | { |
| 572 | struct bio_vec *iv; |
| 573 | unsigned int i; |
| 574 | |
| 575 | bip_for_each_vec(iv, bip, i) { |
| 576 | if (len == 0) { |
| 577 | bip->bip_vcnt = i; |
| 578 | return; |
| 579 | } else if (len >= iv->bv_len) { |
| 580 | len -= iv->bv_len; |
| 581 | } else { /* len < iv->bv_len) */ |
| 582 | iv->bv_len = len; |
| 583 | len = 0; |
| 584 | } |
| 585 | } |
| 586 | } |
| 587 | |
| 588 | /** |
| 589 | * bio_integrity_advance - Advance integrity vector |
| 590 | * @bio: bio whose integrity vector to update |
| 591 | * @bytes_done: number of data bytes that have been completed |
| 592 | * |
| 593 | * Description: This function calculates how many integrity bytes the |
| 594 | * number of completed data bytes correspond to and advances the |
| 595 | * integrity vector accordingly. |
| 596 | */ |
| 597 | void bio_integrity_advance(struct bio *bio, unsigned int bytes_done) |
| 598 | { |
| 599 | struct bio_integrity_payload *bip = bio->bi_integrity; |
| 600 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); |
| 601 | unsigned int nr_sectors; |
| 602 | |
| 603 | BUG_ON(bip == NULL); |
| 604 | BUG_ON(bi == NULL); |
| 605 | |
| 606 | nr_sectors = bio_integrity_hw_sectors(bi, bytes_done >> 9); |
| 607 | bio_integrity_mark_head(bip, nr_sectors * bi->tuple_size); |
| 608 | } |
| 609 | EXPORT_SYMBOL(bio_integrity_advance); |
| 610 | |
| 611 | /** |
| 612 | * bio_integrity_trim - Trim integrity vector |
| 613 | * @bio: bio whose integrity vector to update |
| 614 | * @offset: offset to first data sector |
| 615 | * @sectors: number of data sectors |
| 616 | * |
| 617 | * Description: Used to trim the integrity vector in a cloned bio. |
| 618 | * The ivec will be advanced corresponding to 'offset' data sectors |
| 619 | * and the length will be truncated corresponding to 'len' data |
| 620 | * sectors. |
| 621 | */ |
Jens Axboe | b984679 | 2008-06-17 19:05:48 +0200 | [diff] [blame] | 622 | void bio_integrity_trim(struct bio *bio, unsigned int offset, |
| 623 | unsigned int sectors) |
Martin K. Petersen | 7ba1ba1 | 2008-06-30 20:04:41 +0200 | [diff] [blame] | 624 | { |
| 625 | struct bio_integrity_payload *bip = bio->bi_integrity; |
| 626 | struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev); |
| 627 | unsigned int nr_sectors; |
| 628 | |
| 629 | BUG_ON(bip == NULL); |
| 630 | BUG_ON(bi == NULL); |
| 631 | BUG_ON(!bio_flagged(bio, BIO_CLONED)); |
| 632 | |
| 633 | nr_sectors = bio_integrity_hw_sectors(bi, sectors); |
| 634 | bip->bip_sector = bip->bip_sector + offset; |
| 635 | bio_integrity_mark_head(bip, offset * bi->tuple_size); |
| 636 | bio_integrity_mark_tail(bip, sectors * bi->tuple_size); |
| 637 | } |
| 638 | EXPORT_SYMBOL(bio_integrity_trim); |
| 639 | |
| 640 | /** |
| 641 | * bio_integrity_split - Split integrity metadata |
| 642 | * @bio: Protected bio |
| 643 | * @bp: Resulting bio_pair |
| 644 | * @sectors: Offset |
| 645 | * |
| 646 | * Description: Splits an integrity page into a bio_pair. |
| 647 | */ |
| 648 | void bio_integrity_split(struct bio *bio, struct bio_pair *bp, int sectors) |
| 649 | { |
| 650 | struct blk_integrity *bi; |
| 651 | struct bio_integrity_payload *bip = bio->bi_integrity; |
| 652 | unsigned int nr_sectors; |
| 653 | |
| 654 | if (bio_integrity(bio) == 0) |
| 655 | return; |
| 656 | |
| 657 | bi = bdev_get_integrity(bio->bi_bdev); |
| 658 | BUG_ON(bi == NULL); |
| 659 | BUG_ON(bip->bip_vcnt != 1); |
| 660 | |
| 661 | nr_sectors = bio_integrity_hw_sectors(bi, sectors); |
| 662 | |
| 663 | bp->bio1.bi_integrity = &bp->bip1; |
| 664 | bp->bio2.bi_integrity = &bp->bip2; |
| 665 | |
| 666 | bp->iv1 = bip->bip_vec[0]; |
| 667 | bp->iv2 = bip->bip_vec[0]; |
| 668 | |
| 669 | bp->bip1.bip_vec = &bp->iv1; |
| 670 | bp->bip2.bip_vec = &bp->iv2; |
| 671 | |
| 672 | bp->iv1.bv_len = sectors * bi->tuple_size; |
| 673 | bp->iv2.bv_offset += sectors * bi->tuple_size; |
| 674 | bp->iv2.bv_len -= sectors * bi->tuple_size; |
| 675 | |
| 676 | bp->bip1.bip_sector = bio->bi_integrity->bip_sector; |
| 677 | bp->bip2.bip_sector = bio->bi_integrity->bip_sector + nr_sectors; |
| 678 | |
| 679 | bp->bip1.bip_vcnt = bp->bip2.bip_vcnt = 1; |
| 680 | bp->bip1.bip_idx = bp->bip2.bip_idx = 0; |
| 681 | } |
| 682 | EXPORT_SYMBOL(bio_integrity_split); |
| 683 | |
| 684 | /** |
| 685 | * bio_integrity_clone - Callback for cloning bios with integrity metadata |
| 686 | * @bio: New bio |
| 687 | * @bio_src: Original bio |
| 688 | * @bs: bio_set to allocate bip from |
| 689 | * |
| 690 | * Description: Called to allocate a bip when cloning a bio |
| 691 | */ |
Jens Axboe | b984679 | 2008-06-17 19:05:48 +0200 | [diff] [blame] | 692 | int bio_integrity_clone(struct bio *bio, struct bio *bio_src, |
| 693 | struct bio_set *bs) |
Martin K. Petersen | 7ba1ba1 | 2008-06-30 20:04:41 +0200 | [diff] [blame] | 694 | { |
| 695 | struct bio_integrity_payload *bip_src = bio_src->bi_integrity; |
| 696 | struct bio_integrity_payload *bip; |
| 697 | |
| 698 | BUG_ON(bip_src == NULL); |
| 699 | |
| 700 | bip = bio_integrity_alloc_bioset(bio, GFP_NOIO, bip_src->bip_vcnt, bs); |
| 701 | |
| 702 | if (bip == NULL) |
| 703 | return -EIO; |
| 704 | |
| 705 | memcpy(bip->bip_vec, bip_src->bip_vec, |
| 706 | bip_src->bip_vcnt * sizeof(struct bio_vec)); |
| 707 | |
| 708 | bip->bip_sector = bip_src->bip_sector; |
| 709 | bip->bip_vcnt = bip_src->bip_vcnt; |
| 710 | bip->bip_idx = bip_src->bip_idx; |
| 711 | |
| 712 | return 0; |
| 713 | } |
| 714 | EXPORT_SYMBOL(bio_integrity_clone); |
| 715 | |
| 716 | int bioset_integrity_create(struct bio_set *bs, int pool_size) |
| 717 | { |
| 718 | bs->bio_integrity_pool = mempool_create_slab_pool(pool_size, |
| 719 | bio_integrity_slab); |
| 720 | if (!bs->bio_integrity_pool) |
| 721 | return -1; |
| 722 | |
| 723 | return 0; |
| 724 | } |
| 725 | EXPORT_SYMBOL(bioset_integrity_create); |
| 726 | |
| 727 | void bioset_integrity_free(struct bio_set *bs) |
| 728 | { |
| 729 | if (bs->bio_integrity_pool) |
| 730 | mempool_destroy(bs->bio_integrity_pool); |
| 731 | } |
| 732 | EXPORT_SYMBOL(bioset_integrity_free); |
| 733 | |
| 734 | void __init bio_integrity_init_slab(void) |
| 735 | { |
| 736 | bio_integrity_slab = KMEM_CACHE(bio_integrity_payload, |
| 737 | SLAB_HWCACHE_ALIGN|SLAB_PANIC); |
| 738 | } |
Martin K. Petersen | 7ba1ba1 | 2008-06-30 20:04:41 +0200 | [diff] [blame] | 739 | |
| 740 | static int __init integrity_init(void) |
| 741 | { |
| 742 | kintegrityd_wq = create_workqueue("kintegrityd"); |
| 743 | |
| 744 | if (!kintegrityd_wq) |
| 745 | panic("Failed to create kintegrityd\n"); |
| 746 | |
| 747 | return 0; |
| 748 | } |
| 749 | subsys_initcall(integrity_init); |