block/bio-integrity.c

   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 }