| 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | /* |
| 3 | * bio-integrity.c - bio data integrity extensions |
| 4 | * |
| 5 | * Copyright (C) 2007, 2008, 2009 Oracle Corporation |
| 6 | * Written by: Martin K. Petersen <martin.petersen@oracle.com> |
| 7 | */ |
| 8 | |
| 9 | #include <linux/blk-integrity.h> |
| 10 | #include <linux/mempool.h> |
| 11 | #include <linux/export.h> |
| 12 | #include <linux/bio.h> |
| 13 | #include <linux/workqueue.h> |
| 14 | #include <linux/slab.h> |
| 15 | #include "blk.h" |
| 16 | |
| 17 | static struct kmem_cache *bip_slab; |
| 18 | static struct workqueue_struct *kintegrityd_wq; |
| 19 | |
| 20 | void blk_flush_integrity(void) |
| 21 | { |
| 22 | flush_workqueue(kintegrityd_wq); |
| 23 | } |
| 24 | |
| 25 | static void __bio_integrity_free(struct bio_set *bs, |
| 26 | struct bio_integrity_payload *bip) |
| 27 | { |
| 28 | if (bs && mempool_initialized(&bs->bio_integrity_pool)) { |
| 29 | if (bip->bip_vec) |
| 30 | bvec_free(&bs->bvec_integrity_pool, bip->bip_vec, |
| 31 | bip->bip_max_vcnt); |
| 32 | mempool_free(bip, &bs->bio_integrity_pool); |
| 33 | } else { |
| 34 | kfree(bip); |
| 35 | } |
| 36 | } |
| 37 | |
| 38 | /** |
| 39 | * bio_integrity_alloc - Allocate integrity payload and attach it to bio |
| 40 | * @bio: bio to attach integrity metadata to |
| 41 | * @gfp_mask: Memory allocation mask |
| 42 | * @nr_vecs: Number of integrity metadata scatter-gather elements |
| 43 | * |
| 44 | * Description: This function prepares a bio for attaching integrity |
| 45 | * metadata. nr_vecs specifies the maximum number of pages containing |
| 46 | * integrity metadata that can be attached. |
| 47 | */ |
| 48 | struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio, |
| 49 | gfp_t gfp_mask, |
| 50 | unsigned int nr_vecs) |
| 51 | { |
| 52 | struct bio_integrity_payload *bip; |
| 53 | struct bio_set *bs = bio->bi_pool; |
| 54 | unsigned inline_vecs; |
| 55 | |
| 56 | if (WARN_ON_ONCE(bio_has_crypt_ctx(bio))) |
| 57 | return ERR_PTR(-EOPNOTSUPP); |
| 58 | |
| 59 | if (!bs || !mempool_initialized(&bs->bio_integrity_pool)) { |
| 60 | bip = kmalloc(struct_size(bip, bip_inline_vecs, nr_vecs), gfp_mask); |
| 61 | inline_vecs = nr_vecs; |
| 62 | } else { |
| 63 | bip = mempool_alloc(&bs->bio_integrity_pool, gfp_mask); |
| 64 | inline_vecs = BIO_INLINE_VECS; |
| 65 | } |
| 66 | |
| 67 | if (unlikely(!bip)) |
| 68 | return ERR_PTR(-ENOMEM); |
| 69 | |
| 70 | memset(bip, 0, sizeof(*bip)); |
| 71 | |
| 72 | /* always report as many vecs as asked explicitly, not inline vecs */ |
| 73 | bip->bip_max_vcnt = nr_vecs; |
| 74 | if (nr_vecs > inline_vecs) { |
| 75 | bip->bip_vec = bvec_alloc(&bs->bvec_integrity_pool, |
| 76 | &bip->bip_max_vcnt, gfp_mask); |
| 77 | if (!bip->bip_vec) |
| 78 | goto err; |
| 79 | } else { |
| 80 | bip->bip_vec = bip->bip_inline_vecs; |
| 81 | } |
| 82 | |
| 83 | bip->bip_bio = bio; |
| 84 | bio->bi_integrity = bip; |
| 85 | bio->bi_opf |= REQ_INTEGRITY; |
| 86 | |
| 87 | return bip; |
| 88 | err: |
| 89 | __bio_integrity_free(bs, bip); |
| 90 | return ERR_PTR(-ENOMEM); |
| 91 | } |
| 92 | EXPORT_SYMBOL(bio_integrity_alloc); |
| 93 | |
| 94 | static void bio_integrity_unpin_bvec(struct bio_vec *bv, int nr_vecs, |
| 95 | bool dirty) |
| 96 | { |
| 97 | int i; |
| 98 | |
| 99 | for (i = 0; i < nr_vecs; i++) { |
| 100 | if (dirty && !PageCompound(bv[i].bv_page)) |
| 101 | set_page_dirty_lock(bv[i].bv_page); |
| 102 | unpin_user_page(bv[i].bv_page); |
| 103 | } |
| 104 | } |
| 105 | |
| 106 | static void bio_integrity_uncopy_user(struct bio_integrity_payload *bip) |
| 107 | { |
| 108 | unsigned short nr_vecs = bip->bip_max_vcnt - 1; |
| 109 | struct bio_vec *copy = &bip->bip_vec[1]; |
| 110 | size_t bytes = bip->bip_iter.bi_size; |
| 111 | struct iov_iter iter; |
| 112 | int ret; |
| 113 | |
| 114 | iov_iter_bvec(&iter, ITER_DEST, copy, nr_vecs, bytes); |
| 115 | ret = copy_to_iter(bvec_virt(bip->bip_vec), bytes, &iter); |
| 116 | WARN_ON_ONCE(ret != bytes); |
| 117 | |
| 118 | bio_integrity_unpin_bvec(copy, nr_vecs, true); |
| 119 | } |
| 120 | |
| 121 | static void bio_integrity_unmap_user(struct bio_integrity_payload *bip) |
| 122 | { |
| 123 | bool dirty = bio_data_dir(bip->bip_bio) == READ; |
| 124 | |
| 125 | if (bip->bip_flags & BIP_COPY_USER) { |
| 126 | if (dirty) |
| 127 | bio_integrity_uncopy_user(bip); |
| 128 | kfree(bvec_virt(bip->bip_vec)); |
| 129 | return; |
| 130 | } |
| 131 | |
| 132 | bio_integrity_unpin_bvec(bip->bip_vec, bip->bip_max_vcnt, dirty); |
| 133 | } |
| 134 | |
| 135 | /** |
| 136 | * bio_integrity_free - Free bio integrity payload |
| 137 | * @bio: bio containing bip to be freed |
| 138 | * |
| 139 | * Description: Used to free the integrity portion of a bio. Usually |
| 140 | * called from bio_free(). |
| 141 | */ |
| 142 | void bio_integrity_free(struct bio *bio) |
| 143 | { |
| 144 | struct bio_integrity_payload *bip = bio_integrity(bio); |
| 145 | struct bio_set *bs = bio->bi_pool; |
| 146 | |
| 147 | if (bip->bip_flags & BIP_BLOCK_INTEGRITY) |
| 148 | kfree(bvec_virt(bip->bip_vec)); |
| 149 | else if (bip->bip_flags & BIP_INTEGRITY_USER) |
| 150 | bio_integrity_unmap_user(bip); |
| 151 | |
| 152 | __bio_integrity_free(bs, bip); |
| 153 | bio->bi_integrity = NULL; |
| 154 | bio->bi_opf &= ~REQ_INTEGRITY; |
| 155 | } |
| 156 | |
| 157 | /** |
| 158 | * bio_integrity_add_page - Attach integrity metadata |
| 159 | * @bio: bio to update |
| 160 | * @page: page containing integrity metadata |
| 161 | * @len: number of bytes of integrity metadata in page |
| 162 | * @offset: start offset within page |
| 163 | * |
| 164 | * Description: Attach a page containing integrity metadata to bio. |
| 165 | */ |
| 166 | int bio_integrity_add_page(struct bio *bio, struct page *page, |
| 167 | unsigned int len, unsigned int offset) |
| 168 | { |
| 169 | struct request_queue *q = bdev_get_queue(bio->bi_bdev); |
| 170 | struct bio_integrity_payload *bip = bio_integrity(bio); |
| 171 | |
| 172 | if (((bip->bip_iter.bi_size + len) >> SECTOR_SHIFT) > |
| 173 | queue_max_hw_sectors(q)) |
| 174 | return 0; |
| 175 | |
| 176 | if (bip->bip_vcnt > 0) { |
| 177 | struct bio_vec *bv = &bip->bip_vec[bip->bip_vcnt - 1]; |
| 178 | bool same_page = false; |
| 179 | |
| 180 | if (bvec_try_merge_hw_page(q, bv, page, len, offset, |
| 181 | &same_page)) { |
| 182 | bip->bip_iter.bi_size += len; |
| 183 | return len; |
| 184 | } |
| 185 | |
| 186 | if (bip->bip_vcnt >= |
| 187 | min(bip->bip_max_vcnt, queue_max_integrity_segments(q))) |
| 188 | return 0; |
| 189 | |
| 190 | /* |
| 191 | * If the queue doesn't support SG gaps and adding this segment |
| 192 | * would create a gap, disallow it. |
| 193 | */ |
| 194 | if (bvec_gap_to_prev(&q->limits, bv, offset)) |
| 195 | return 0; |
| 196 | } |
| 197 | |
| 198 | bvec_set_page(&bip->bip_vec[bip->bip_vcnt], page, len, offset); |
| 199 | bip->bip_vcnt++; |
| 200 | bip->bip_iter.bi_size += len; |
| 201 | |
| 202 | return len; |
| 203 | } |
| 204 | EXPORT_SYMBOL(bio_integrity_add_page); |
| 205 | |
| 206 | static int bio_integrity_copy_user(struct bio *bio, struct bio_vec *bvec, |
| 207 | int nr_vecs, unsigned int len, |
| 208 | unsigned int direction, u32 seed) |
| 209 | { |
| 210 | bool write = direction == ITER_SOURCE; |
| 211 | struct bio_integrity_payload *bip; |
| 212 | struct iov_iter iter; |
| 213 | void *buf; |
| 214 | int ret; |
| 215 | |
| 216 | buf = kmalloc(len, GFP_KERNEL); |
| 217 | if (!buf) |
| 218 | return -ENOMEM; |
| 219 | |
| 220 | if (write) { |
| 221 | iov_iter_bvec(&iter, direction, bvec, nr_vecs, len); |
| 222 | if (!copy_from_iter_full(buf, len, &iter)) { |
| 223 | ret = -EFAULT; |
| 224 | goto free_buf; |
| 225 | } |
| 226 | |
| 227 | bip = bio_integrity_alloc(bio, GFP_KERNEL, 1); |
| 228 | } else { |
| 229 | memset(buf, 0, len); |
| 230 | |
| 231 | /* |
| 232 | * We need to preserve the original bvec and the number of vecs |
| 233 | * in it for completion handling |
| 234 | */ |
| 235 | bip = bio_integrity_alloc(bio, GFP_KERNEL, nr_vecs + 1); |
| 236 | } |
| 237 | |
| 238 | if (IS_ERR(bip)) { |
| 239 | ret = PTR_ERR(bip); |
| 240 | goto free_buf; |
| 241 | } |
| 242 | |
| 243 | if (write) |
| 244 | bio_integrity_unpin_bvec(bvec, nr_vecs, false); |
| 245 | else |
| 246 | memcpy(&bip->bip_vec[1], bvec, nr_vecs * sizeof(*bvec)); |
| 247 | |
| 248 | ret = bio_integrity_add_page(bio, virt_to_page(buf), len, |
| 249 | offset_in_page(buf)); |
| 250 | if (ret != len) { |
| 251 | ret = -ENOMEM; |
| 252 | goto free_bip; |
| 253 | } |
| 254 | |
| 255 | bip->bip_flags |= BIP_INTEGRITY_USER | BIP_COPY_USER; |
| 256 | bip->bip_iter.bi_sector = seed; |
| 257 | return 0; |
| 258 | free_bip: |
| 259 | bio_integrity_free(bio); |
| 260 | free_buf: |
| 261 | kfree(buf); |
| 262 | return ret; |
| 263 | } |
| 264 | |
| 265 | static int bio_integrity_init_user(struct bio *bio, struct bio_vec *bvec, |
| 266 | int nr_vecs, unsigned int len, u32 seed) |
| 267 | { |
| 268 | struct bio_integrity_payload *bip; |
| 269 | |
| 270 | bip = bio_integrity_alloc(bio, GFP_KERNEL, nr_vecs); |
| 271 | if (IS_ERR(bip)) |
| 272 | return PTR_ERR(bip); |
| 273 | |
| 274 | memcpy(bip->bip_vec, bvec, nr_vecs * sizeof(*bvec)); |
| 275 | bip->bip_flags |= BIP_INTEGRITY_USER; |
| 276 | bip->bip_iter.bi_sector = seed; |
| 277 | bip->bip_iter.bi_size = len; |
| 278 | return 0; |
| 279 | } |
| 280 | |
| 281 | static unsigned int bvec_from_pages(struct bio_vec *bvec, struct page **pages, |
| 282 | int nr_vecs, ssize_t bytes, ssize_t offset) |
| 283 | { |
| 284 | unsigned int nr_bvecs = 0; |
| 285 | int i, j; |
| 286 | |
| 287 | for (i = 0; i < nr_vecs; i = j) { |
| 288 | size_t size = min_t(size_t, bytes, PAGE_SIZE - offset); |
| 289 | struct folio *folio = page_folio(pages[i]); |
| 290 | |
| 291 | bytes -= size; |
| 292 | for (j = i + 1; j < nr_vecs; j++) { |
| 293 | size_t next = min_t(size_t, PAGE_SIZE, bytes); |
| 294 | |
| 295 | if (page_folio(pages[j]) != folio || |
| 296 | pages[j] != pages[j - 1] + 1) |
| 297 | break; |
| 298 | unpin_user_page(pages[j]); |
| 299 | size += next; |
| 300 | bytes -= next; |
| 301 | } |
| 302 | |
| 303 | bvec_set_page(&bvec[nr_bvecs], pages[i], size, offset); |
| 304 | offset = 0; |
| 305 | nr_bvecs++; |
| 306 | } |
| 307 | |
| 308 | return nr_bvecs; |
| 309 | } |
| 310 | |
| 311 | int bio_integrity_map_user(struct bio *bio, void __user *ubuf, ssize_t bytes, |
| 312 | u32 seed) |
| 313 | { |
| 314 | struct request_queue *q = bdev_get_queue(bio->bi_bdev); |
| 315 | unsigned int align = q->dma_pad_mask | queue_dma_alignment(q); |
| 316 | struct page *stack_pages[UIO_FASTIOV], **pages = stack_pages; |
| 317 | struct bio_vec stack_vec[UIO_FASTIOV], *bvec = stack_vec; |
| 318 | unsigned int direction, nr_bvecs; |
| 319 | struct iov_iter iter; |
| 320 | int ret, nr_vecs; |
| 321 | size_t offset; |
| 322 | bool copy; |
| 323 | |
| 324 | if (bio_integrity(bio)) |
| 325 | return -EINVAL; |
| 326 | if (bytes >> SECTOR_SHIFT > queue_max_hw_sectors(q)) |
| 327 | return -E2BIG; |
| 328 | |
| 329 | if (bio_data_dir(bio) == READ) |
| 330 | direction = ITER_DEST; |
| 331 | else |
| 332 | direction = ITER_SOURCE; |
| 333 | |
| 334 | iov_iter_ubuf(&iter, direction, ubuf, bytes); |
| 335 | nr_vecs = iov_iter_npages(&iter, BIO_MAX_VECS + 1); |
| 336 | if (nr_vecs > BIO_MAX_VECS) |
| 337 | return -E2BIG; |
| 338 | if (nr_vecs > UIO_FASTIOV) { |
| 339 | bvec = kcalloc(nr_vecs, sizeof(*bvec), GFP_KERNEL); |
| 340 | if (!bvec) |
| 341 | return -ENOMEM; |
| 342 | pages = NULL; |
| 343 | } |
| 344 | |
| 345 | copy = !iov_iter_is_aligned(&iter, align, align); |
| 346 | ret = iov_iter_extract_pages(&iter, &pages, bytes, nr_vecs, 0, &offset); |
| 347 | if (unlikely(ret < 0)) |
| 348 | goto free_bvec; |
| 349 | |
| 350 | nr_bvecs = bvec_from_pages(bvec, pages, nr_vecs, bytes, offset); |
| 351 | if (pages != stack_pages) |
| 352 | kvfree(pages); |
| 353 | if (nr_bvecs > queue_max_integrity_segments(q)) |
| 354 | copy = true; |
| 355 | |
| 356 | if (copy) |
| 357 | ret = bio_integrity_copy_user(bio, bvec, nr_bvecs, bytes, |
| 358 | direction, seed); |
| 359 | else |
| 360 | ret = bio_integrity_init_user(bio, bvec, nr_bvecs, bytes, seed); |
| 361 | if (ret) |
| 362 | goto release_pages; |
| 363 | if (bvec != stack_vec) |
| 364 | kfree(bvec); |
| 365 | |
| 366 | return 0; |
| 367 | |
| 368 | release_pages: |
| 369 | bio_integrity_unpin_bvec(bvec, nr_bvecs, false); |
| 370 | free_bvec: |
| 371 | if (bvec != stack_vec) |
| 372 | kfree(bvec); |
| 373 | return ret; |
| 374 | } |
| 375 | EXPORT_SYMBOL_GPL(bio_integrity_map_user); |
| 376 | |
| 377 | /** |
| 378 | * bio_integrity_process - Process integrity metadata for a bio |
| 379 | * @bio: bio to generate/verify integrity metadata for |
| 380 | * @proc_iter: iterator to process |
| 381 | * @proc_fn: Pointer to the relevant processing function |
| 382 | */ |
| 383 | static blk_status_t bio_integrity_process(struct bio *bio, |
| 384 | struct bvec_iter *proc_iter, integrity_processing_fn *proc_fn) |
| 385 | { |
| 386 | struct blk_integrity *bi = blk_get_integrity(bio->bi_bdev->bd_disk); |
| 387 | struct blk_integrity_iter iter; |
| 388 | struct bvec_iter bviter; |
| 389 | struct bio_vec bv; |
| 390 | struct bio_integrity_payload *bip = bio_integrity(bio); |
| 391 | blk_status_t ret = BLK_STS_OK; |
| 392 | |
| 393 | iter.disk_name = bio->bi_bdev->bd_disk->disk_name; |
| 394 | iter.interval = 1 << bi->interval_exp; |
| 395 | iter.tuple_size = bi->tuple_size; |
| 396 | iter.seed = proc_iter->bi_sector; |
| 397 | iter.prot_buf = bvec_virt(bip->bip_vec); |
| 398 | |
| 399 | __bio_for_each_segment(bv, bio, bviter, *proc_iter) { |
| 400 | void *kaddr = bvec_kmap_local(&bv); |
| 401 | |
| 402 | iter.data_buf = kaddr; |
| 403 | iter.data_size = bv.bv_len; |
| 404 | ret = proc_fn(&iter); |
| 405 | kunmap_local(kaddr); |
| 406 | |
| 407 | if (ret) |
| 408 | break; |
| 409 | |
| 410 | } |
| 411 | return ret; |
| 412 | } |
| 413 | |
| 414 | /** |
| 415 | * bio_integrity_prep - Prepare bio for integrity I/O |
| 416 | * @bio: bio to prepare |
| 417 | * |
| 418 | * Description: Checks if the bio already has an integrity payload attached. |
| 419 | * If it does, the payload has been generated by another kernel subsystem, |
| 420 | * and we just pass it through. Otherwise allocates integrity payload. |
| 421 | * The bio must have data direction, target device and start sector set priot |
| 422 | * to calling. In the WRITE case, integrity metadata will be generated using |
| 423 | * the block device's integrity function. In the READ case, the buffer |
| 424 | * will be prepared for DMA and a suitable end_io handler set up. |
| 425 | */ |
| 426 | bool bio_integrity_prep(struct bio *bio) |
| 427 | { |
| 428 | struct bio_integrity_payload *bip; |
| 429 | struct blk_integrity *bi = blk_get_integrity(bio->bi_bdev->bd_disk); |
| 430 | void *buf; |
| 431 | unsigned long start, end; |
| 432 | unsigned int len, nr_pages; |
| 433 | unsigned int bytes, offset, i; |
| 434 | |
| 435 | if (!bi) |
| 436 | return true; |
| 437 | |
| 438 | if (bio_op(bio) != REQ_OP_READ && bio_op(bio) != REQ_OP_WRITE) |
| 439 | return true; |
| 440 | |
| 441 | if (!bio_sectors(bio)) |
| 442 | return true; |
| 443 | |
| 444 | /* Already protected? */ |
| 445 | if (bio_integrity(bio)) |
| 446 | return true; |
| 447 | |
| 448 | if (bio_data_dir(bio) == READ) { |
| 449 | if (!bi->profile->verify_fn || |
| 450 | !(bi->flags & BLK_INTEGRITY_VERIFY)) |
| 451 | return true; |
| 452 | } else { |
| 453 | if (!bi->profile->generate_fn || |
| 454 | !(bi->flags & BLK_INTEGRITY_GENERATE)) |
| 455 | return true; |
| 456 | } |
| 457 | |
| 458 | /* Allocate kernel buffer for protection data */ |
| 459 | len = bio_integrity_bytes(bi, bio_sectors(bio)); |
| 460 | buf = kmalloc(len, GFP_NOIO); |
| 461 | if (unlikely(buf == NULL)) { |
| 462 | printk(KERN_ERR "could not allocate integrity buffer\n"); |
| 463 | goto err_end_io; |
| 464 | } |
| 465 | |
| 466 | end = (((unsigned long) buf) + len + PAGE_SIZE - 1) >> PAGE_SHIFT; |
| 467 | start = ((unsigned long) buf) >> PAGE_SHIFT; |
| 468 | nr_pages = end - start; |
| 469 | |
| 470 | /* Allocate bio integrity payload and integrity vectors */ |
| 471 | bip = bio_integrity_alloc(bio, GFP_NOIO, nr_pages); |
| 472 | if (IS_ERR(bip)) { |
| 473 | printk(KERN_ERR "could not allocate data integrity bioset\n"); |
| 474 | kfree(buf); |
| 475 | goto err_end_io; |
| 476 | } |
| 477 | |
| 478 | bip->bip_flags |= BIP_BLOCK_INTEGRITY; |
| 479 | bip_set_seed(bip, bio->bi_iter.bi_sector); |
| 480 | |
| 481 | if (bi->flags & BLK_INTEGRITY_IP_CHECKSUM) |
| 482 | bip->bip_flags |= BIP_IP_CHECKSUM; |
| 483 | |
| 484 | /* Map it */ |
| 485 | offset = offset_in_page(buf); |
| 486 | for (i = 0; i < nr_pages && len > 0; i++) { |
| 487 | bytes = PAGE_SIZE - offset; |
| 488 | |
| 489 | if (bytes > len) |
| 490 | bytes = len; |
| 491 | |
| 492 | if (bio_integrity_add_page(bio, virt_to_page(buf), |
| 493 | bytes, offset) < bytes) { |
| 494 | printk(KERN_ERR "could not attach integrity payload\n"); |
| 495 | goto err_end_io; |
| 496 | } |
| 497 | |
| 498 | buf += bytes; |
| 499 | len -= bytes; |
| 500 | offset = 0; |
| 501 | } |
| 502 | |
| 503 | /* Auto-generate integrity metadata if this is a write */ |
| 504 | if (bio_data_dir(bio) == WRITE) { |
| 505 | bio_integrity_process(bio, &bio->bi_iter, |
| 506 | bi->profile->generate_fn); |
| 507 | } else { |
| 508 | bip->bio_iter = bio->bi_iter; |
| 509 | } |
| 510 | return true; |
| 511 | |
| 512 | err_end_io: |
| 513 | bio->bi_status = BLK_STS_RESOURCE; |
| 514 | bio_endio(bio); |
| 515 | return false; |
| 516 | } |
| 517 | EXPORT_SYMBOL(bio_integrity_prep); |
| 518 | |
| 519 | /** |
| 520 | * bio_integrity_verify_fn - Integrity I/O completion worker |
| 521 | * @work: Work struct stored in bio to be verified |
| 522 | * |
| 523 | * Description: This workqueue function is called to complete a READ |
| 524 | * request. The function verifies the transferred integrity metadata |
| 525 | * and then calls the original bio end_io function. |
| 526 | */ |
| 527 | static void bio_integrity_verify_fn(struct work_struct *work) |
| 528 | { |
| 529 | struct bio_integrity_payload *bip = |
| 530 | container_of(work, struct bio_integrity_payload, bip_work); |
| 531 | struct bio *bio = bip->bip_bio; |
| 532 | struct blk_integrity *bi = blk_get_integrity(bio->bi_bdev->bd_disk); |
| 533 | |
| 534 | /* |
| 535 | * At the moment verify is called bio's iterator was advanced |
| 536 | * during split and completion, we need to rewind iterator to |
| 537 | * it's original position. |
| 538 | */ |
| 539 | bio->bi_status = bio_integrity_process(bio, &bip->bio_iter, |
| 540 | bi->profile->verify_fn); |
| 541 | bio_integrity_free(bio); |
| 542 | bio_endio(bio); |
| 543 | } |
| 544 | |
| 545 | /** |
| 546 | * __bio_integrity_endio - Integrity I/O completion function |
| 547 | * @bio: Protected bio |
| 548 | * |
| 549 | * Description: Completion for integrity I/O |
| 550 | * |
| 551 | * Normally I/O completion is done in interrupt context. However, |
| 552 | * verifying I/O integrity is a time-consuming task which must be run |
| 553 | * in process context. This function postpones completion |
| 554 | * accordingly. |
| 555 | */ |
| 556 | bool __bio_integrity_endio(struct bio *bio) |
| 557 | { |
| 558 | struct blk_integrity *bi = blk_get_integrity(bio->bi_bdev->bd_disk); |
| 559 | struct bio_integrity_payload *bip = bio_integrity(bio); |
| 560 | |
| 561 | if (bio_op(bio) == REQ_OP_READ && !bio->bi_status && |
| 562 | (bip->bip_flags & BIP_BLOCK_INTEGRITY) && bi->profile->verify_fn) { |
| 563 | INIT_WORK(&bip->bip_work, bio_integrity_verify_fn); |
| 564 | queue_work(kintegrityd_wq, &bip->bip_work); |
| 565 | return false; |
| 566 | } |
| 567 | |
| 568 | bio_integrity_free(bio); |
| 569 | return true; |
| 570 | } |
| 571 | |
| 572 | /** |
| 573 | * bio_integrity_advance - Advance integrity vector |
| 574 | * @bio: bio whose integrity vector to update |
| 575 | * @bytes_done: number of data bytes that have been completed |
| 576 | * |
| 577 | * Description: This function calculates how many integrity bytes the |
| 578 | * number of completed data bytes correspond to and advances the |
| 579 | * integrity vector accordingly. |
| 580 | */ |
| 581 | void bio_integrity_advance(struct bio *bio, unsigned int bytes_done) |
| 582 | { |
| 583 | struct bio_integrity_payload *bip = bio_integrity(bio); |
| 584 | struct blk_integrity *bi = blk_get_integrity(bio->bi_bdev->bd_disk); |
| 585 | unsigned bytes = bio_integrity_bytes(bi, bytes_done >> 9); |
| 586 | |
| 587 | bip->bip_iter.bi_sector += bio_integrity_intervals(bi, bytes_done >> 9); |
| 588 | bvec_iter_advance(bip->bip_vec, &bip->bip_iter, bytes); |
| 589 | } |
| 590 | |
| 591 | /** |
| 592 | * bio_integrity_trim - Trim integrity vector |
| 593 | * @bio: bio whose integrity vector to update |
| 594 | * |
| 595 | * Description: Used to trim the integrity vector in a cloned bio. |
| 596 | */ |
| 597 | void bio_integrity_trim(struct bio *bio) |
| 598 | { |
| 599 | struct bio_integrity_payload *bip = bio_integrity(bio); |
| 600 | struct blk_integrity *bi = blk_get_integrity(bio->bi_bdev->bd_disk); |
| 601 | |
| 602 | bip->bip_iter.bi_size = bio_integrity_bytes(bi, bio_sectors(bio)); |
| 603 | } |
| 604 | EXPORT_SYMBOL(bio_integrity_trim); |
| 605 | |
| 606 | /** |
| 607 | * bio_integrity_clone - Callback for cloning bios with integrity metadata |
| 608 | * @bio: New bio |
| 609 | * @bio_src: Original bio |
| 610 | * @gfp_mask: Memory allocation mask |
| 611 | * |
| 612 | * Description: Called to allocate a bip when cloning a bio |
| 613 | */ |
| 614 | int bio_integrity_clone(struct bio *bio, struct bio *bio_src, |
| 615 | gfp_t gfp_mask) |
| 616 | { |
| 617 | struct bio_integrity_payload *bip_src = bio_integrity(bio_src); |
| 618 | struct bio_integrity_payload *bip; |
| 619 | |
| 620 | BUG_ON(bip_src == NULL); |
| 621 | |
| 622 | bip = bio_integrity_alloc(bio, gfp_mask, bip_src->bip_vcnt); |
| 623 | if (IS_ERR(bip)) |
| 624 | return PTR_ERR(bip); |
| 625 | |
| 626 | memcpy(bip->bip_vec, bip_src->bip_vec, |
| 627 | bip_src->bip_vcnt * sizeof(struct bio_vec)); |
| 628 | |
| 629 | bip->bip_vcnt = bip_src->bip_vcnt; |
| 630 | bip->bip_iter = bip_src->bip_iter; |
| 631 | bip->bip_flags = bip_src->bip_flags & ~BIP_BLOCK_INTEGRITY; |
| 632 | |
| 633 | return 0; |
| 634 | } |
| 635 | |
| 636 | int bioset_integrity_create(struct bio_set *bs, int pool_size) |
| 637 | { |
| 638 | if (mempool_initialized(&bs->bio_integrity_pool)) |
| 639 | return 0; |
| 640 | |
| 641 | if (mempool_init_slab_pool(&bs->bio_integrity_pool, |
| 642 | pool_size, bip_slab)) |
| 643 | return -1; |
| 644 | |
| 645 | if (biovec_init_pool(&bs->bvec_integrity_pool, pool_size)) { |
| 646 | mempool_exit(&bs->bio_integrity_pool); |
| 647 | return -1; |
| 648 | } |
| 649 | |
| 650 | return 0; |
| 651 | } |
| 652 | EXPORT_SYMBOL(bioset_integrity_create); |
| 653 | |
| 654 | void bioset_integrity_free(struct bio_set *bs) |
| 655 | { |
| 656 | mempool_exit(&bs->bio_integrity_pool); |
| 657 | mempool_exit(&bs->bvec_integrity_pool); |
| 658 | } |
| 659 | |
| 660 | void __init bio_integrity_init(void) |
| 661 | { |
| 662 | /* |
| 663 | * kintegrityd won't block much but may burn a lot of CPU cycles. |
| 664 | * Make it highpri CPU intensive wq with max concurrency of 1. |
| 665 | */ |
| 666 | kintegrityd_wq = alloc_workqueue("kintegrityd", WQ_MEM_RECLAIM | |
| 667 | WQ_HIGHPRI | WQ_CPU_INTENSIVE, 1); |
| 668 | if (!kintegrityd_wq) |
| 669 | panic("Failed to create kintegrityd\n"); |
| 670 | |
| 671 | bip_slab = kmem_cache_create("bio_integrity_payload", |
| 672 | sizeof(struct bio_integrity_payload) + |
| 673 | sizeof(struct bio_vec) * BIO_INLINE_VECS, |
| 674 | 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); |
| 675 | } |