block/bio-integrity.c

   1 /*
   2  * bio-integrity.c - bio data integrity extensions
   3  *
   4  * Copyright (C) 2007, 2008, 2009 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/export.h>
  26 #include <linux/bio.h>
  27 #include <linux/workqueue.h>
  28 #include <linux/slab.h>
  29
  30 #define BIP_INLINE_VECS 4
  31
  32 static struct kmem_cache *bip_slab;
  33 static struct workqueue_struct *kintegrityd_wq;
  34
  35 /**
  36  * bio_integrity_alloc - Allocate integrity payload and attach it to bio
  37  * @bio:        bio to attach integrity metadata to
  38  * @gfp_mask:   Memory allocation mask
  39  * @nr_vecs:    Number of integrity metadata scatter-gather elements
  40  *
  41  * Description: This function prepares a bio for attaching integrity
  42  * metadata.  nr_vecs specifies the maximum number of pages containing
  43  * integrity metadata that can be attached.
  44  */
  45 struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio,
  46                                                   gfp_t gfp_mask,
  47                                                   unsigned int nr_vecs)
  48 {
  49         struct bio_integrity_payload *bip;
  50         struct bio_set *bs = bio->bi_pool;
  51         unsigned long idx = BIO_POOL_NONE;
  52         unsigned inline_vecs;
  53
  54         if (!bs) {
  55                 bip = kmalloc(sizeof(struct bio_integrity_payload) +
  56                               sizeof(struct bio_vec) * nr_vecs, gfp_mask);
  57                 inline_vecs = nr_vecs;
  58         } else {
  59                 bip = mempool_alloc(bs->bio_integrity_pool, gfp_mask);
  60                 inline_vecs = BIP_INLINE_VECS;
  61         }
  62
  63         if (unlikely(!bip))
  64                 return NULL;
  65
  66         memset(bip, 0, sizeof(*bip));
  67
  68         if (nr_vecs > inline_vecs) {
  69                 bip->bip_vec = bvec_alloc(gfp_mask, nr_vecs, &idx,
  70                                           bs->bvec_integrity_pool);
  71                 if (!bip->bip_vec)
  72                         goto err;
  73         } else {
  74                 bip->bip_vec = bip->bip_inline_vecs;
  75         }
  76
  77         bip->bip_slab = idx;
  78         bip->bip_bio = bio;
  79         bio->bi_integrity = bip;
  80
  81         return bip;
  82 err:
  83         mempool_free(bip, bs->bio_integrity_pool);
  84         return NULL;
  85 }
  86 EXPORT_SYMBOL(bio_integrity_alloc);
  87
  88 /**
  89  * bio_integrity_free - Free bio integrity payload
  90  * @bio:        bio containing bip to be freed
  91  *
  92  * Description: Used to free the integrity portion of a bio. Usually
  93  * called from bio_free().
  94  */
  95 void bio_integrity_free(struct bio *bio)
  96 {
  97         struct bio_integrity_payload *bip = bio->bi_integrity;
  98         struct bio_set *bs = bio->bi_pool;
  99
 100         if (bip->bip_owns_buf)
 101                 kfree(bip->bip_buf);
 102
 103         if (bs) {
 104                 if (bip->bip_slab != BIO_POOL_NONE)
 105                         bvec_free(bs->bvec_integrity_pool, bip->bip_vec,
 106                                   bip->bip_slab);
 107
 108                 mempool_free(bip, bs->bio_integrity_pool);
 109         } else {
 110                 kfree(bip);
 111         }
 112
 113         bio->bi_integrity = NULL;
 114 }
 115 EXPORT_SYMBOL(bio_integrity_free);
 116
 117 static inline unsigned int bip_integrity_vecs(struct bio_integrity_payload *bip)
 118 {
 119         if (bip->bip_slab == BIO_POOL_NONE)
 120                 return BIP_INLINE_VECS;
 121
 122         return bvec_nr_vecs(bip->bip_slab);
 123 }
 124
 125 /**
 126  * bio_integrity_add_page - Attach integrity metadata
 127  * @bio:        bio to update
 128  * @page:       page containing integrity metadata
 129  * @len:        number of bytes of integrity metadata in page
 130  * @offset:     start offset within page
 131  *
 132  * Description: Attach a page containing integrity metadata to bio.
 133  */
 134 int bio_integrity_add_page(struct bio *bio, struct page *page,
 135                            unsigned int len, unsigned int offset)
 136 {
 137         struct bio_integrity_payload *bip = bio->bi_integrity;
 138         struct bio_vec *iv;
 139
 140         if (bip->bip_vcnt >= bip_integrity_vecs(bip)) {
 141                 printk(KERN_ERR "%s: bip_vec full\n", __func__);
 142                 return 0;
 143         }
 144
 145         iv = bip->bip_vec + bip->bip_vcnt;
 146
 147         iv->bv_page = page;
 148         iv->bv_len = len;
 149         iv->bv_offset = offset;
 150         bip->bip_vcnt++;
 151
 152         return len;
 153 }
 154 EXPORT_SYMBOL(bio_integrity_add_page);
 155
 156 static int bdev_integrity_enabled(struct block_device *bdev, int rw)
 157 {
 158         struct blk_integrity *bi = bdev_get_integrity(bdev);
 159
 160         if (bi == NULL)
 161                 return 0;
 162
 163         if (rw == READ && bi->verify_fn != NULL &&
 164             (bi->flags & INTEGRITY_FLAG_READ))
 165                 return 1;
 166
 167         if (rw == WRITE && bi->generate_fn != NULL &&
 168             (bi->flags & INTEGRITY_FLAG_WRITE))
 169                 return 1;
 170
 171         return 0;
 172 }
 173
 174 /**
 175  * bio_integrity_enabled - Check whether integrity can be passed
 176  * @bio:        bio to check
 177  *
 178  * Description: Determines whether bio_integrity_prep() can be called
 179  * on this bio or not.  bio data direction and target device must be
 180  * set prior to calling.  The functions honors the write_generate and
 181  * read_verify flags in sysfs.
 182  */
 183 int bio_integrity_enabled(struct bio *bio)
 184 {
 185         if (!bio_is_rw(bio))
 186                 return 0;
 187
 188         /* Already protected? */
 189         if (bio_integrity(bio))
 190                 return 0;
 191
 192         return bdev_integrity_enabled(bio->bi_bdev, bio_data_dir(bio));
 193 }
 194 EXPORT_SYMBOL(bio_integrity_enabled);
 195
 196 /**
 197  * bio_integrity_hw_sectors - Convert 512b sectors to hardware ditto
 198  * @bi:         blk_integrity profile for device
 199  * @sectors:    Number of 512 sectors to convert
 200  *
 201  * Description: The block layer calculates everything in 512 byte
 202  * sectors but integrity metadata is done in terms of the hardware
 203  * sector size of the storage device.  Convert the block layer sectors
 204  * to physical sectors.
 205  */
 206 static inline unsigned int bio_integrity_hw_sectors(struct blk_integrity *bi,
 207                                                     unsigned int sectors)
 208 {
 209         /* At this point there are only 512b or 4096b DIF/EPP devices */
 210         if (bi->sector_size == 4096)
 211                 return sectors >>= 3;
 212
 213         return sectors;
 214 }
 215
 216 static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
 217                                                unsigned int sectors)
 218 {
 219         return bio_integrity_hw_sectors(bi, sectors) * bi->tuple_size;
 220 }
 221
 222 /**
 223  * bio_integrity_tag_size - Retrieve integrity tag space
 224  * @bio:        bio to inspect
 225  *
 226  * Description: Returns the maximum number of tag bytes that can be
 227  * attached to this bio. Filesystems can use this to determine how
 228  * much metadata to attach to an I/O.
 229  */
 230 unsigned int bio_integrity_tag_size(struct bio *bio)
 231 {
 232         struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
 233
 234         BUG_ON(bio->bi_iter.bi_size == 0);
 235
 236         return bi->tag_size * (bio->bi_iter.bi_size / bi->sector_size);
 237 }
 238 EXPORT_SYMBOL(bio_integrity_tag_size);
 239
 240 static int bio_integrity_tag(struct bio *bio, void *tag_buf, unsigned int len,
 241                              int set)
 242 {
 243         struct bio_integrity_payload *bip = bio->bi_integrity;
 244         struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
 245         unsigned int nr_sectors;
 246
 247         BUG_ON(bip->bip_buf == NULL);
 248
 249         if (bi->tag_size == 0)
 250                 return -1;
 251
 252         nr_sectors = bio_integrity_hw_sectors(bi,
 253                                         DIV_ROUND_UP(len, bi->tag_size));
 254
 255         if (nr_sectors * bi->tuple_size > bip->bip_iter.bi_size) {
 256                 printk(KERN_ERR "%s: tag too big for bio: %u > %u\n", __func__,
 257                        nr_sectors * bi->tuple_size, bip->bip_iter.bi_size);
 258                 return -1;
 259         }
 260
 261         if (set)
 262                 bi->set_tag_fn(bip->bip_buf, tag_buf, nr_sectors);
 263         else
 264                 bi->get_tag_fn(bip->bip_buf, tag_buf, nr_sectors);
 265
 266         return 0;
 267 }
 268
 269 /**
 270  * bio_integrity_set_tag - Attach a tag buffer to a bio
 271  * @bio:        bio to attach buffer to
 272  * @tag_buf:    Pointer to a buffer containing tag data
 273  * @len:        Length of the included buffer
 274  *
 275  * Description: Use this function to tag a bio by leveraging the extra
 276  * space provided by devices formatted with integrity protection.  The
 277  * size of the integrity buffer must be <= to the size reported by
 278  * bio_integrity_tag_size().
 279  */
 280 int bio_integrity_set_tag(struct bio *bio, void *tag_buf, unsigned int len)
 281 {
 282         BUG_ON(bio_data_dir(bio) != WRITE);
 283
 284         return bio_integrity_tag(bio, tag_buf, len, 1);
 285 }
 286 EXPORT_SYMBOL(bio_integrity_set_tag);
 287
 288 /**
 289  * bio_integrity_get_tag - Retrieve a tag buffer from a bio
 290  * @bio:        bio to retrieve buffer from
 291  * @tag_buf:    Pointer to a buffer for the tag data
 292  * @len:        Length of the target buffer
 293  *
 294  * Description: Use this function to retrieve the tag buffer from a
 295  * completed I/O. The size of the integrity buffer must be <= to the
 296  * size reported by bio_integrity_tag_size().
 297  */
 298 int bio_integrity_get_tag(struct bio *bio, void *tag_buf, unsigned int len)
 299 {
 300         BUG_ON(bio_data_dir(bio) != READ);
 301
 302         return bio_integrity_tag(bio, tag_buf, len, 0);
 303 }
 304 EXPORT_SYMBOL(bio_integrity_get_tag);
 305
 306 /**
 307  * bio_integrity_generate_verify - Generate/verify integrity metadata for a bio
 308  * @bio:        bio to generate/verify integrity metadata for
 309  * @operate:    operate number, 1 for generate, 0 for verify
 310  */
 311 static int bio_integrity_generate_verify(struct bio *bio, int operate)
 312 {
 313         struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
 314         struct blk_integrity_exchg bix;
 315         struct bio_vec *bv;
 316         sector_t sector;
 317         unsigned int sectors, ret = 0, i;
 318         void *prot_buf = bio->bi_integrity->bip_buf;
 319
 320         if (operate)
 321                 sector = bio->bi_iter.bi_sector;
 322         else
 323                 sector = bio->bi_integrity->bip_iter.bi_sector;
 324
 325         bix.disk_name = bio->bi_bdev->bd_disk->disk_name;
 326         bix.sector_size = bi->sector_size;
 327
 328         bio_for_each_segment_all(bv, bio, i) {
 329                 void *kaddr = kmap_atomic(bv->bv_page);
 330                 bix.data_buf = kaddr + bv->bv_offset;
 331                 bix.data_size = bv->bv_len;
 332                 bix.prot_buf = prot_buf;
 333                 bix.sector = sector;
 334
 335                 if (operate)
 336                         bi->generate_fn(&bix);
 337                 else {
 338                         ret = bi->verify_fn(&bix);
 339                         if (ret) {
 340                                 kunmap_atomic(kaddr);
 341                                 return ret;
 342                         }
 343                 }
 344
 345                 sectors = bv->bv_len / bi->sector_size;
 346                 sector += sectors;
 347                 prot_buf += sectors * bi->tuple_size;
 348
 349                 kunmap_atomic(kaddr);
 350         }
 351         return ret;
 352 }
 353
 354 /**
 355  * bio_integrity_generate - Generate integrity metadata for a bio
 356  * @bio:        bio to generate integrity metadata for
 357  *
 358  * Description: Generates integrity metadata for a bio by calling the
 359  * block device's generation callback function.  The bio must have a
 360  * bip attached with enough room to accommodate the generated
 361  * integrity metadata.
 362  */
 363 static void bio_integrity_generate(struct bio *bio)
 364 {
 365         bio_integrity_generate_verify(bio, 1);
 366 }
 367
 368 static inline unsigned short blk_integrity_tuple_size(struct blk_integrity *bi)
 369 {
 370         if (bi)
 371                 return bi->tuple_size;
 372
 373         return 0;
 374 }
 375
 376 /**
 377  * bio_integrity_prep - Prepare bio for integrity I/O
 378  * @bio:        bio to prepare
 379  *
 380  * Description: Allocates a buffer for integrity metadata, maps the
 381  * pages and attaches them to a bio.  The bio must have data
 382  * direction, target device and start sector set priot to calling.  In
 383  * the WRITE case, integrity metadata will be generated using the
 384  * block device's integrity function.  In the READ case, the buffer
 385  * will be prepared for DMA and a suitable end_io handler set up.
 386  */
 387 int bio_integrity_prep(struct bio *bio)
 388 {
 389         struct bio_integrity_payload *bip;
 390         struct blk_integrity *bi;
 391         struct request_queue *q;
 392         void *buf;
 393         unsigned long start, end;
 394         unsigned int len, nr_pages;
 395         unsigned int bytes, offset, i;
 396         unsigned int sectors;
 397
 398         bi = bdev_get_integrity(bio->bi_bdev);
 399         q = bdev_get_queue(bio->bi_bdev);
 400         BUG_ON(bi == NULL);
 401         BUG_ON(bio_integrity(bio));
 402
 403         sectors = bio_integrity_hw_sectors(bi, bio_sectors(bio));
 404
 405         /* Allocate kernel buffer for protection data */
 406         len = sectors * blk_integrity_tuple_size(bi);
 407         buf = kmalloc(len, GFP_NOIO | q->bounce_gfp);
 408         if (unlikely(buf == NULL)) {
 409                 printk(KERN_ERR "could not allocate integrity buffer\n");
 410                 return -ENOMEM;
 411         }
 412
 413         end = (((unsigned long) buf) + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
 414         start = ((unsigned long) buf) >> PAGE_SHIFT;
 415         nr_pages = end - start;
 416
 417         /* Allocate bio integrity payload and integrity vectors */
 418         bip = bio_integrity_alloc(bio, GFP_NOIO, nr_pages);
 419         if (unlikely(bip == NULL)) {
 420                 printk(KERN_ERR "could not allocate data integrity bioset\n");
 421                 kfree(buf);
 422                 return -EIO;
 423         }
 424
 425         bip->bip_owns_buf = 1;
 426         bip->bip_buf = buf;
 427         bip->bip_iter.bi_size = len;
 428         bip->bip_iter.bi_sector = bio->bi_iter.bi_sector;
 429
 430         /* Map it */
 431         offset = offset_in_page(buf);
 432         for (i = 0 ; i < nr_pages ; i++) {
 433                 int ret;
 434                 bytes = PAGE_SIZE - offset;
 435
 436                 if (len <= 0)
 437                         break;
 438
 439                 if (bytes > len)
 440                         bytes = len;
 441
 442                 ret = bio_integrity_add_page(bio, virt_to_page(buf),
 443                                              bytes, offset);
 444
 445                 if (ret == 0)
 446                         return 0;
 447
 448                 if (ret < bytes)
 449                         break;
 450
 451                 buf += bytes;
 452                 len -= bytes;
 453                 offset = 0;
 454         }
 455
 456         /* Install custom I/O completion handler if read verify is enabled */
 457         if (bio_data_dir(bio) == READ) {
 458                 bip->bip_end_io = bio->bi_end_io;
 459                 bio->bi_end_io = bio_integrity_endio;
 460         }
 461
 462         /* Auto-generate integrity metadata if this is a write */
 463         if (bio_data_dir(bio) == WRITE)
 464                 bio_integrity_generate(bio);
 465
 466         return 0;
 467 }
 468 EXPORT_SYMBOL(bio_integrity_prep);
 469
 470 /**
 471  * bio_integrity_verify - Verify integrity metadata for a bio
 472  * @bio:        bio to verify
 473  *
 474  * Description: This function is called to verify the integrity of a
 475  * bio.  The data in the bio io_vec is compared to the integrity
 476  * metadata returned by the HBA.
 477  */
 478 static int bio_integrity_verify(struct bio *bio)
 479 {
 480         return bio_integrity_generate_verify(bio, 0);
 481 }
 482
 483 /**
 484  * bio_integrity_verify_fn - Integrity I/O completion worker
 485  * @work:       Work struct stored in bio to be verified
 486  *
 487  * Description: This workqueue function is called to complete a READ
 488  * request.  The function verifies the transferred integrity metadata
 489  * and then calls the original bio end_io function.
 490  */
 491 static void bio_integrity_verify_fn(struct work_struct *work)
 492 {
 493         struct bio_integrity_payload *bip =
 494                 container_of(work, struct bio_integrity_payload, bip_work);
 495         struct bio *bio = bip->bip_bio;
 496         int error;
 497
 498         error = bio_integrity_verify(bio);
 499
 500         /* Restore original bio completion handler */
 501         bio->bi_end_io = bip->bip_end_io;
 502         bio_endio_nodec(bio, error);
 503 }
 504
 505 /**
 506  * bio_integrity_endio - Integrity I/O completion function
 507  * @bio:        Protected bio
 508  * @error:      Pointer to errno
 509  *
 510  * Description: Completion for integrity I/O
 511  *
 512  * Normally I/O completion is done in interrupt context.  However,
 513  * verifying I/O integrity is a time-consuming task which must be run
 514  * in process context.  This function postpones completion
 515  * accordingly.
 516  */
 517 void bio_integrity_endio(struct bio *bio, int error)
 518 {
 519         struct bio_integrity_payload *bip = bio->bi_integrity;
 520
 521         BUG_ON(bip->bip_bio != bio);
 522
 523         /* In case of an I/O error there is no point in verifying the
 524          * integrity metadata.  Restore original bio end_io handler
 525          * and run it.
 526          */
 527         if (error) {
 528                 bio->bi_end_io = bip->bip_end_io;
 529                 bio_endio(bio, error);
 530
 531                 return;
 532         }
 533
 534         INIT_WORK(&bip->bip_work, bio_integrity_verify_fn);
 535         queue_work(kintegrityd_wq, &bip->bip_work);
 536 }
 537 EXPORT_SYMBOL(bio_integrity_endio);
 538
 539 /**
 540  * bio_integrity_advance - Advance integrity vector
 541  * @bio:        bio whose integrity vector to update
 542  * @bytes_done: number of data bytes that have been completed
 543  *
 544  * Description: This function calculates how many integrity bytes the
 545  * number of completed data bytes correspond to and advances the
 546  * integrity vector accordingly.
 547  */
 548 void bio_integrity_advance(struct bio *bio, unsigned int bytes_done)
 549 {
 550         struct bio_integrity_payload *bip = bio->bi_integrity;
 551         struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
 552         unsigned bytes = bio_integrity_bytes(bi, bytes_done >> 9);
 553
 554         bvec_iter_advance(bip->bip_vec, &bip->bip_iter, bytes);
 555 }
 556 EXPORT_SYMBOL(bio_integrity_advance);
 557
 558 /**
 559  * bio_integrity_trim - Trim integrity vector
 560  * @bio:        bio whose integrity vector to update
 561  * @offset:     offset to first data sector
 562  * @sectors:    number of data sectors
 563  *
 564  * Description: Used to trim the integrity vector in a cloned bio.
 565  * The ivec will be advanced corresponding to 'offset' data sectors
 566  * and the length will be truncated corresponding to 'len' data
 567  * sectors.
 568  */
 569 void bio_integrity_trim(struct bio *bio, unsigned int offset,
 570                         unsigned int sectors)
 571 {
 572         struct bio_integrity_payload *bip = bio->bi_integrity;
 573         struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
 574
 575         bio_integrity_advance(bio, offset << 9);
 576         bip->bip_iter.bi_size = bio_integrity_bytes(bi, sectors);
 577 }
 578 EXPORT_SYMBOL(bio_integrity_trim);
 579
 580 /**
 581  * bio_integrity_clone - Callback for cloning bios with integrity metadata
 582  * @bio:        New bio
 583  * @bio_src:    Original bio
 584  * @gfp_mask:   Memory allocation mask
 585  *
 586  * Description: Called to allocate a bip when cloning a bio
 587  */
 588 int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
 589                         gfp_t gfp_mask)
 590 {
 591         struct bio_integrity_payload *bip_src = bio_src->bi_integrity;
 592         struct bio_integrity_payload *bip;
 593
 594         BUG_ON(bip_src == NULL);
 595
 596         bip = bio_integrity_alloc(bio, gfp_mask, bip_src->bip_vcnt);
 597
 598         if (bip == NULL)
 599                 return -EIO;
 600
 601         memcpy(bip->bip_vec, bip_src->bip_vec,
 602                bip_src->bip_vcnt * sizeof(struct bio_vec));
 603
 604         bip->bip_vcnt = bip_src->bip_vcnt;
 605         bip->bip_iter = bip_src->bip_iter;
 606
 607         return 0;
 608 }
 609 EXPORT_SYMBOL(bio_integrity_clone);
 610
 611 int bioset_integrity_create(struct bio_set *bs, int pool_size)
 612 {
 613         if (bs->bio_integrity_pool)
 614                 return 0;
 615
 616         bs->bio_integrity_pool = mempool_create_slab_pool(pool_size, bip_slab);
 617         if (!bs->bio_integrity_pool)
 618                 return -1;
 619
 620         bs->bvec_integrity_pool = biovec_create_pool(pool_size);
 621         if (!bs->bvec_integrity_pool) {
 622                 mempool_destroy(bs->bio_integrity_pool);
 623                 return -1;
 624         }
 625
 626         return 0;
 627 }
 628 EXPORT_SYMBOL(bioset_integrity_create);
 629
 630 void bioset_integrity_free(struct bio_set *bs)
 631 {
 632         if (bs->bio_integrity_pool)
 633                 mempool_destroy(bs->bio_integrity_pool);
 634
 635         if (bs->bvec_integrity_pool)
 636                 mempool_destroy(bs->bvec_integrity_pool);
 637 }
 638 EXPORT_SYMBOL(bioset_integrity_free);
 639
 640 void __init bio_integrity_init(void)
 641 {
 642         /*
 643          * kintegrityd won't block much but may burn a lot of CPU cycles.
 644          * Make it highpri CPU intensive wq with max concurrency of 1.
 645          */
 646         kintegrityd_wq = alloc_workqueue("kintegrityd", WQ_MEM_RECLAIM |
 647                                          WQ_HIGHPRI | WQ_CPU_INTENSIVE, 1);
 648         if (!kintegrityd_wq)
 649                 panic("Failed to create kintegrityd\n");
 650
 651         bip_slab = kmem_cache_create("bio_integrity_payload",
 652                                      sizeof(struct bio_integrity_payload) +
 653                                      sizeof(struct bio_vec) * BIP_INLINE_VECS,
 654                                      0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
 655         if (!bip_slab)
 656                 panic("Failed to create slab\n");
 657 }