drivers/target/target_core_sbc.c

   1 /*
   2  * SCSI Block Commands (SBC) parsing and emulation.
   3  *
   4  * (c) Copyright 2002-2013 Datera, Inc.
   5  *
   6  * Nicholas A. Bellinger <nab@kernel.org>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  21  */
  22
  23 #include <linux/kernel.h>
  24 #include <linux/module.h>
  25 #include <linux/ratelimit.h>
  26 #include <linux/crc-t10dif.h>
  27 #include <linux/t10-pi.h>
  28 #include <asm/unaligned.h>
  29 #include <scsi/scsi_proto.h>
  30 #include <scsi/scsi_tcq.h>
  31
  32 #include <target/target_core_base.h>
  33 #include <target/target_core_backend.h>
  34 #include <target/target_core_fabric.h>
  35
  36 #include "target_core_internal.h"
  37 #include "target_core_ua.h"
  38 #include "target_core_alua.h"
  39
  40 static sense_reason_t
  41 sbc_check_prot(struct se_device *, struct se_cmd *, unsigned char *, u32, bool);
  42 static sense_reason_t sbc_execute_unmap(struct se_cmd *cmd);
  43
  44 static sense_reason_t
  45 sbc_emulate_readcapacity(struct se_cmd *cmd)
  46 {
  47         struct se_device *dev = cmd->se_dev;
  48         unsigned char *cdb = cmd->t_task_cdb;
  49         unsigned long long blocks_long = dev->transport->get_blocks(dev);
  50         unsigned char *rbuf;
  51         unsigned char buf[8];
  52         u32 blocks;
  53
  54         /*
  55          * SBC-2 says:
  56          *   If the PMI bit is set to zero and the LOGICAL BLOCK
  57          *   ADDRESS field is not set to zero, the device server shall
  58          *   terminate the command with CHECK CONDITION status with
  59          *   the sense key set to ILLEGAL REQUEST and the additional
  60          *   sense code set to INVALID FIELD IN CDB.
  61          *
  62          * In SBC-3, these fields are obsolete, but some SCSI
  63          * compliance tests actually check this, so we might as well
  64          * follow SBC-2.
  65          */
  66         if (!(cdb[8] & 1) && !!(cdb[2] | cdb[3] | cdb[4] | cdb[5]))
  67                 return TCM_INVALID_CDB_FIELD;
  68
  69         if (blocks_long >= 0x00000000ffffffff)
  70                 blocks = 0xffffffff;
  71         else
  72                 blocks = (u32)blocks_long;
  73
  74         put_unaligned_be32(blocks, &buf[0]);
  75         put_unaligned_be32(dev->dev_attrib.block_size, &buf[4]);
  76
  77         rbuf = transport_kmap_data_sg(cmd);
  78         if (rbuf) {
  79                 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
  80                 transport_kunmap_data_sg(cmd);
  81         }
  82
  83         target_complete_cmd_with_length(cmd, GOOD, 8);
  84         return 0;
  85 }
  86
  87 static sense_reason_t
  88 sbc_emulate_readcapacity_16(struct se_cmd *cmd)
  89 {
  90         struct se_device *dev = cmd->se_dev;
  91         struct se_session *sess = cmd->se_sess;
  92         int pi_prot_type = dev->dev_attrib.pi_prot_type;
  93
  94         unsigned char *rbuf;
  95         unsigned char buf[32];
  96         unsigned long long blocks = dev->transport->get_blocks(dev);
  97
  98         memset(buf, 0, sizeof(buf));
  99         put_unaligned_be64(blocks, &buf[0]);
 100         put_unaligned_be32(dev->dev_attrib.block_size, &buf[8]);
 101         /*
 102          * Set P_TYPE and PROT_EN bits for DIF support
 103          */
 104         if (sess->sup_prot_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS)) {
 105                 /*
 106                  * Only override a device's pi_prot_type if no T10-PI is
 107                  * available, and sess_prot_type has been explicitly enabled.
 108                  */
 109                 if (!pi_prot_type)
 110                         pi_prot_type = sess->sess_prot_type;
 111
 112                 if (pi_prot_type)
 113                         buf[12] = (pi_prot_type - 1) << 1 | 0x1;
 114         }
 115
 116         if (dev->transport->get_lbppbe)
 117                 buf[13] = dev->transport->get_lbppbe(dev) & 0x0f;
 118
 119         if (dev->transport->get_alignment_offset_lbas) {
 120                 u16 lalba = dev->transport->get_alignment_offset_lbas(dev);
 121
 122                 put_unaligned_be16(lalba, &buf[14]);
 123         }
 124
 125         /*
 126          * Set Thin Provisioning Enable bit following sbc3r22 in section
 127          * READ CAPACITY (16) byte 14 if emulate_tpu or emulate_tpws is enabled.
 128          */
 129         if (dev->dev_attrib.emulate_tpu || dev->dev_attrib.emulate_tpws) {
 130                 buf[14] |= 0x80;
 131
 132                 /*
 133                  * LBPRZ signifies that zeroes will be read back from an LBA after
 134                  * an UNMAP or WRITE SAME w/ unmap bit (sbc3r36 5.16.2)
 135                  */
 136                 if (dev->dev_attrib.unmap_zeroes_data)
 137                         buf[14] |= 0x40;
 138         }
 139
 140         rbuf = transport_kmap_data_sg(cmd);
 141         if (rbuf) {
 142                 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
 143                 transport_kunmap_data_sg(cmd);
 144         }
 145
 146         target_complete_cmd_with_length(cmd, GOOD, 32);
 147         return 0;
 148 }
 149
 150 static sense_reason_t
 151 sbc_emulate_startstop(struct se_cmd *cmd)
 152 {
 153         unsigned char *cdb = cmd->t_task_cdb;
 154
 155         /*
 156          * See sbc3r36 section 5.25
 157          * Immediate bit should be set since there is nothing to complete
 158          * POWER CONDITION MODIFIER 0h
 159          */
 160         if (!(cdb[1] & 1) || cdb[2] || cdb[3])
 161                 return TCM_INVALID_CDB_FIELD;
 162
 163         /*
 164          * See sbc3r36 section 5.25
 165          * POWER CONDITION 0h START_VALID - process START and LOEJ
 166          */
 167         if (cdb[4] >> 4 & 0xf)
 168                 return TCM_INVALID_CDB_FIELD;
 169
 170         /*
 171          * See sbc3r36 section 5.25
 172          * LOEJ 0h - nothing to load or unload
 173          * START 1h - we are ready
 174          */
 175         if (!(cdb[4] & 1) || (cdb[4] & 2) || (cdb[4] & 4))
 176                 return TCM_INVALID_CDB_FIELD;
 177
 178         target_complete_cmd(cmd, SAM_STAT_GOOD);
 179         return 0;
 180 }
 181
 182 sector_t sbc_get_write_same_sectors(struct se_cmd *cmd)
 183 {
 184         u32 num_blocks;
 185
 186         if (cmd->t_task_cdb[0] == WRITE_SAME)
 187                 num_blocks = get_unaligned_be16(&cmd->t_task_cdb[7]);
 188         else if (cmd->t_task_cdb[0] == WRITE_SAME_16)
 189                 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[10]);
 190         else /* WRITE_SAME_32 via VARIABLE_LENGTH_CMD */
 191                 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[28]);
 192
 193         /*
 194          * Use the explicit range when non zero is supplied, otherwise calculate
 195          * the remaining range based on ->get_blocks() - starting LBA.
 196          */
 197         if (num_blocks)
 198                 return num_blocks;
 199
 200         return cmd->se_dev->transport->get_blocks(cmd->se_dev) -
 201                 cmd->t_task_lba + 1;
 202 }
 203 EXPORT_SYMBOL(sbc_get_write_same_sectors);
 204
 205 static sense_reason_t
 206 sbc_execute_write_same_unmap(struct se_cmd *cmd)
 207 {
 208         struct sbc_ops *ops = cmd->protocol_data;
 209         sector_t nolb = sbc_get_write_same_sectors(cmd);
 210         sense_reason_t ret;
 211
 212         if (nolb) {
 213                 ret = ops->execute_unmap(cmd, cmd->t_task_lba, nolb);
 214                 if (ret)
 215                         return ret;
 216         }
 217
 218         target_complete_cmd(cmd, GOOD);
 219         return 0;
 220 }
 221
 222 static sense_reason_t
 223 sbc_emulate_noop(struct se_cmd *cmd)
 224 {
 225         target_complete_cmd(cmd, GOOD);
 226         return 0;
 227 }
 228
 229 static inline u32 sbc_get_size(struct se_cmd *cmd, u32 sectors)
 230 {
 231         return cmd->se_dev->dev_attrib.block_size * sectors;
 232 }
 233
 234 static inline u32 transport_get_sectors_6(unsigned char *cdb)
 235 {
 236         /*
 237          * Use 8-bit sector value.  SBC-3 says:
 238          *
 239          *   A TRANSFER LENGTH field set to zero specifies that 256
 240          *   logical blocks shall be written.  Any other value
 241          *   specifies the number of logical blocks that shall be
 242          *   written.
 243          */
 244         return cdb[4] ? : 256;
 245 }
 246
 247 static inline u32 transport_get_sectors_10(unsigned char *cdb)
 248 {
 249         return get_unaligned_be16(&cdb[7]);
 250 }
 251
 252 static inline u32 transport_get_sectors_12(unsigned char *cdb)
 253 {
 254         return get_unaligned_be32(&cdb[6]);
 255 }
 256
 257 static inline u32 transport_get_sectors_16(unsigned char *cdb)
 258 {
 259         return get_unaligned_be32(&cdb[10]);
 260 }
 261
 262 /*
 263  * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
 264  */
 265 static inline u32 transport_get_sectors_32(unsigned char *cdb)
 266 {
 267         return get_unaligned_be32(&cdb[28]);
 268
 269 }
 270
 271 static inline u32 transport_lba_21(unsigned char *cdb)
 272 {
 273         return get_unaligned_be24(&cdb[1]) & 0x1fffff;
 274 }
 275
 276 static inline u32 transport_lba_32(unsigned char *cdb)
 277 {
 278         return get_unaligned_be32(&cdb[2]);
 279 }
 280
 281 static inline unsigned long long transport_lba_64(unsigned char *cdb)
 282 {
 283         return get_unaligned_be64(&cdb[2]);
 284 }
 285
 286 /*
 287  * For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs
 288  */
 289 static inline unsigned long long transport_lba_64_ext(unsigned char *cdb)
 290 {
 291         return get_unaligned_be64(&cdb[12]);
 292 }
 293
 294 static sense_reason_t
 295 sbc_setup_write_same(struct se_cmd *cmd, unsigned char *flags, struct sbc_ops *ops)
 296 {
 297         struct se_device *dev = cmd->se_dev;
 298         sector_t end_lba = dev->transport->get_blocks(dev) + 1;
 299         unsigned int sectors = sbc_get_write_same_sectors(cmd);
 300         sense_reason_t ret;
 301
 302         if ((flags[0] & 0x04) || (flags[0] & 0x02)) {
 303                 pr_err("WRITE_SAME PBDATA and LBDATA"
 304                         " bits not supported for Block Discard"
 305                         " Emulation\n");
 306                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 307         }
 308         if (sectors > cmd->se_dev->dev_attrib.max_write_same_len) {
 309                 pr_warn("WRITE_SAME sectors: %u exceeds max_write_same_len: %u\n",
 310                         sectors, cmd->se_dev->dev_attrib.max_write_same_len);
 311                 return TCM_INVALID_CDB_FIELD;
 312         }
 313         /*
 314          * Sanity check for LBA wrap and request past end of device.
 315          */
 316         if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
 317             ((cmd->t_task_lba + sectors) > end_lba)) {
 318                 pr_err("WRITE_SAME exceeds last lba %llu (lba %llu, sectors %u)\n",
 319                        (unsigned long long)end_lba, cmd->t_task_lba, sectors);
 320                 return TCM_ADDRESS_OUT_OF_RANGE;
 321         }
 322
 323         /* We always have ANC_SUP == 0 so setting ANCHOR is always an error */
 324         if (flags[0] & 0x10) {
 325                 pr_warn("WRITE SAME with ANCHOR not supported\n");
 326                 return TCM_INVALID_CDB_FIELD;
 327         }
 328         /*
 329          * Special case for WRITE_SAME w/ UNMAP=1 that ends up getting
 330          * translated into block discard requests within backend code.
 331          */
 332         if (flags[0] & 0x08) {
 333                 if (!ops->execute_unmap)
 334                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 335
 336                 if (!dev->dev_attrib.emulate_tpws) {
 337                         pr_err("Got WRITE_SAME w/ UNMAP=1, but backend device"
 338                                " has emulate_tpws disabled\n");
 339                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 340                 }
 341                 cmd->execute_cmd = sbc_execute_write_same_unmap;
 342                 return 0;
 343         }
 344         if (!ops->execute_write_same)
 345                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 346
 347         ret = sbc_check_prot(dev, cmd, &cmd->t_task_cdb[0], sectors, true);
 348         if (ret)
 349                 return ret;
 350
 351         cmd->execute_cmd = ops->execute_write_same;
 352         return 0;
 353 }
 354
 355 static sense_reason_t xdreadwrite_callback(struct se_cmd *cmd, bool success,
 356                                            int *post_ret)
 357 {
 358         unsigned char *buf, *addr;
 359         struct scatterlist *sg;
 360         unsigned int offset;
 361         sense_reason_t ret = TCM_NO_SENSE;
 362         int i, count;
 363
 364         if (!success)
 365                 return 0;
 366
 367         /*
 368          * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
 369          *
 370          * 1) read the specified logical block(s);
 371          * 2) transfer logical blocks from the data-out buffer;
 372          * 3) XOR the logical blocks transferred from the data-out buffer with
 373          *    the logical blocks read, storing the resulting XOR data in a buffer;
 374          * 4) if the DISABLE WRITE bit is set to zero, then write the logical
 375          *    blocks transferred from the data-out buffer; and
 376          * 5) transfer the resulting XOR data to the data-in buffer.
 377          */
 378         buf = kmalloc(cmd->data_length, GFP_KERNEL);
 379         if (!buf) {
 380                 pr_err("Unable to allocate xor_callback buf\n");
 381                 return TCM_OUT_OF_RESOURCES;
 382         }
 383         /*
 384          * Copy the scatterlist WRITE buffer located at cmd->t_data_sg
 385          * into the locally allocated *buf
 386          */
 387         sg_copy_to_buffer(cmd->t_data_sg,
 388                           cmd->t_data_nents,
 389                           buf,
 390                           cmd->data_length);
 391
 392         /*
 393          * Now perform the XOR against the BIDI read memory located at
 394          * cmd->t_mem_bidi_list
 395          */
 396
 397         offset = 0;
 398         for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
 399                 addr = kmap_atomic(sg_page(sg));
 400                 if (!addr) {
 401                         ret = TCM_OUT_OF_RESOURCES;
 402                         goto out;
 403                 }
 404
 405                 for (i = 0; i < sg->length; i++)
 406                         *(addr + sg->offset + i) ^= *(buf + offset + i);
 407
 408                 offset += sg->length;
 409                 kunmap_atomic(addr);
 410         }
 411
 412 out:
 413         kfree(buf);
 414         return ret;
 415 }
 416
 417 static sense_reason_t
 418 sbc_execute_rw(struct se_cmd *cmd)
 419 {
 420         struct sbc_ops *ops = cmd->protocol_data;
 421
 422         return ops->execute_rw(cmd, cmd->t_data_sg, cmd->t_data_nents,
 423                                cmd->data_direction);
 424 }
 425
 426 static sense_reason_t compare_and_write_post(struct se_cmd *cmd, bool success,
 427                                              int *post_ret)
 428 {
 429         struct se_device *dev = cmd->se_dev;
 430         sense_reason_t ret = TCM_NO_SENSE;
 431
 432         spin_lock_irq(&cmd->t_state_lock);
 433         if (success) {
 434                 *post_ret = 1;
 435
 436                 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION)
 437                         ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 438         }
 439         spin_unlock_irq(&cmd->t_state_lock);
 440
 441         /*
 442          * Unlock ->caw_sem originally obtained during sbc_compare_and_write()
 443          * before the original READ I/O submission.
 444          */
 445         up(&dev->caw_sem);
 446
 447         return ret;
 448 }
 449
 450 static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool success,
 451                                                  int *post_ret)
 452 {
 453         struct se_device *dev = cmd->se_dev;
 454         struct sg_table write_tbl = { };
 455         struct scatterlist *write_sg, *sg;
 456         unsigned char *buf = NULL, *addr;
 457         struct sg_mapping_iter m;
 458         unsigned int offset = 0, len;
 459         unsigned int nlbas = cmd->t_task_nolb;
 460         unsigned int block_size = dev->dev_attrib.block_size;
 461         unsigned int compare_len = (nlbas * block_size);
 462         sense_reason_t ret = TCM_NO_SENSE;
 463         int rc, i;
 464
 465         /*
 466          * Handle early failure in transport_generic_request_failure(),
 467          * which will not have taken ->caw_sem yet..
 468          */
 469         if (!success && (!cmd->t_data_sg || !cmd->t_bidi_data_sg))
 470                 return TCM_NO_SENSE;
 471         /*
 472          * Handle special case for zero-length COMPARE_AND_WRITE
 473          */
 474         if (!cmd->data_length)
 475                 goto out;
 476         /*
 477          * Immediately exit + release dev->caw_sem if command has already
 478          * been failed with a non-zero SCSI status.
 479          */
 480         if (cmd->scsi_status) {
 481                 pr_debug("compare_and_write_callback: non zero scsi_status:"
 482                         " 0x%02x\n", cmd->scsi_status);
 483                 *post_ret = 1;
 484                 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION)
 485                         ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 486                 goto out;
 487         }
 488
 489         buf = kzalloc(cmd->data_length, GFP_KERNEL);
 490         if (!buf) {
 491                 pr_err("Unable to allocate compare_and_write buf\n");
 492                 ret = TCM_OUT_OF_RESOURCES;
 493                 goto out;
 494         }
 495
 496         if (sg_alloc_table(&write_tbl, cmd->t_data_nents, GFP_KERNEL) < 0) {
 497                 pr_err("Unable to allocate compare_and_write sg\n");
 498                 ret = TCM_OUT_OF_RESOURCES;
 499                 goto out;
 500         }
 501         write_sg = write_tbl.sgl;
 502         /*
 503          * Setup verify and write data payloads from total NumberLBAs.
 504          */
 505         rc = sg_copy_to_buffer(cmd->t_data_sg, cmd->t_data_nents, buf,
 506                                cmd->data_length);
 507         if (!rc) {
 508                 pr_err("sg_copy_to_buffer() failed for compare_and_write\n");
 509                 ret = TCM_OUT_OF_RESOURCES;
 510                 goto out;
 511         }
 512         /*
 513          * Compare against SCSI READ payload against verify payload
 514          */
 515         for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, i) {
 516                 addr = (unsigned char *)kmap_atomic(sg_page(sg));
 517                 if (!addr) {
 518                         ret = TCM_OUT_OF_RESOURCES;
 519                         goto out;
 520                 }
 521
 522                 len = min(sg->length, compare_len);
 523
 524                 if (memcmp(addr, buf + offset, len)) {
 525                         pr_warn("Detected MISCOMPARE for addr: %p buf: %p\n",
 526                                 addr, buf + offset);
 527                         kunmap_atomic(addr);
 528                         goto miscompare;
 529                 }
 530                 kunmap_atomic(addr);
 531
 532                 offset += len;
 533                 compare_len -= len;
 534                 if (!compare_len)
 535                         break;
 536         }
 537
 538         i = 0;
 539         len = cmd->t_task_nolb * block_size;
 540         sg_miter_start(&m, cmd->t_data_sg, cmd->t_data_nents, SG_MITER_TO_SG);
 541         /*
 542          * Currently assumes NoLB=1 and SGLs are PAGE_SIZE..
 543          */
 544         while (len) {
 545                 sg_miter_next(&m);
 546
 547                 if (block_size < PAGE_SIZE) {
 548                         sg_set_page(&write_sg[i], m.page, block_size,
 549                                     m.piter.sg->offset + block_size);
 550                 } else {
 551                         sg_miter_next(&m);
 552                         sg_set_page(&write_sg[i], m.page, block_size,
 553                                     m.piter.sg->offset);
 554                 }
 555                 len -= block_size;
 556                 i++;
 557         }
 558         sg_miter_stop(&m);
 559         /*
 560          * Save the original SGL + nents values before updating to new
 561          * assignments, to be released in transport_free_pages() ->
 562          * transport_reset_sgl_orig()
 563          */
 564         cmd->t_data_sg_orig = cmd->t_data_sg;
 565         cmd->t_data_sg = write_sg;
 566         cmd->t_data_nents_orig = cmd->t_data_nents;
 567         cmd->t_data_nents = 1;
 568
 569         cmd->sam_task_attr = TCM_HEAD_TAG;
 570         cmd->transport_complete_callback = compare_and_write_post;
 571         /*
 572          * Now reset ->execute_cmd() to the normal sbc_execute_rw() handler
 573          * for submitting the adjusted SGL to write instance user-data.
 574          */
 575         cmd->execute_cmd = sbc_execute_rw;
 576
 577         spin_lock_irq(&cmd->t_state_lock);
 578         cmd->t_state = TRANSPORT_PROCESSING;
 579         cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT;
 580         spin_unlock_irq(&cmd->t_state_lock);
 581
 582         __target_execute_cmd(cmd, false);
 583
 584         kfree(buf);
 585         return ret;
 586
 587 miscompare:
 588         pr_warn("Target/%s: Send MISCOMPARE check condition and sense\n",
 589                 dev->transport->name);
 590         ret = TCM_MISCOMPARE_VERIFY;
 591 out:
 592         /*
 593          * In the MISCOMPARE or failure case, unlock ->caw_sem obtained in
 594          * sbc_compare_and_write() before the original READ I/O submission.
 595          */
 596         up(&dev->caw_sem);
 597         sg_free_table(&write_tbl);
 598         kfree(buf);
 599         return ret;
 600 }
 601
 602 static sense_reason_t
 603 sbc_compare_and_write(struct se_cmd *cmd)
 604 {
 605         struct sbc_ops *ops = cmd->protocol_data;
 606         struct se_device *dev = cmd->se_dev;
 607         sense_reason_t ret;
 608         int rc;
 609         /*
 610          * Submit the READ first for COMPARE_AND_WRITE to perform the
 611          * comparision using SGLs at cmd->t_bidi_data_sg..
 612          */
 613         rc = down_interruptible(&dev->caw_sem);
 614         if (rc != 0) {
 615                 cmd->transport_complete_callback = NULL;
 616                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 617         }
 618         /*
 619          * Reset cmd->data_length to individual block_size in order to not
 620          * confuse backend drivers that depend on this value matching the
 621          * size of the I/O being submitted.
 622          */
 623         cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size;
 624
 625         ret = ops->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents,
 626                               DMA_FROM_DEVICE);
 627         if (ret) {
 628                 cmd->transport_complete_callback = NULL;
 629                 up(&dev->caw_sem);
 630                 return ret;
 631         }
 632         /*
 633          * Unlock of dev->caw_sem to occur in compare_and_write_callback()
 634          * upon MISCOMPARE, or in compare_and_write_done() upon completion
 635          * of WRITE instance user-data.
 636          */
 637         return TCM_NO_SENSE;
 638 }
 639
 640 static int
 641 sbc_set_prot_op_checks(u8 protect, bool fabric_prot, enum target_prot_type prot_type,
 642                        bool is_write, struct se_cmd *cmd)
 643 {
 644         if (is_write) {
 645                 cmd->prot_op = fabric_prot ? TARGET_PROT_DOUT_STRIP :
 646                                protect ? TARGET_PROT_DOUT_PASS :
 647                                TARGET_PROT_DOUT_INSERT;
 648                 switch (protect) {
 649                 case 0x0:
 650                 case 0x3:
 651                         cmd->prot_checks = 0;
 652                         break;
 653                 case 0x1:
 654                 case 0x5:
 655                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 656                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 657                                 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 658                         break;
 659                 case 0x2:
 660                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 661                                 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 662                         break;
 663                 case 0x4:
 664                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 665                         break;
 666                 default:
 667                         pr_err("Unsupported protect field %d\n", protect);
 668                         return -EINVAL;
 669                 }
 670         } else {
 671                 cmd->prot_op = fabric_prot ? TARGET_PROT_DIN_INSERT :
 672                                protect ? TARGET_PROT_DIN_PASS :
 673                                TARGET_PROT_DIN_STRIP;
 674                 switch (protect) {
 675                 case 0x0:
 676                 case 0x1:
 677                 case 0x5:
 678                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 679                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 680                                 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 681                         break;
 682                 case 0x2:
 683                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 684                                 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 685                         break;
 686                 case 0x3:
 687                         cmd->prot_checks = 0;
 688                         break;
 689                 case 0x4:
 690                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 691                         break;
 692                 default:
 693                         pr_err("Unsupported protect field %d\n", protect);
 694                         return -EINVAL;
 695                 }
 696         }
 697
 698         return 0;
 699 }
 700
 701 static sense_reason_t
 702 sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb,
 703                u32 sectors, bool is_write)
 704 {
 705         u8 protect = cdb[1] >> 5;
 706         int sp_ops = cmd->se_sess->sup_prot_ops;
 707         int pi_prot_type = dev->dev_attrib.pi_prot_type;
 708         bool fabric_prot = false;
 709
 710         if (!cmd->t_prot_sg || !cmd->t_prot_nents) {
 711                 if (unlikely(protect &&
 712                     !dev->dev_attrib.pi_prot_type && !cmd->se_sess->sess_prot_type)) {
 713                         pr_err("CDB contains protect bit, but device + fabric does"
 714                                " not advertise PROTECT=1 feature bit\n");
 715                         return TCM_INVALID_CDB_FIELD;
 716                 }
 717                 if (cmd->prot_pto)
 718                         return TCM_NO_SENSE;
 719         }
 720
 721         switch (dev->dev_attrib.pi_prot_type) {
 722         case TARGET_DIF_TYPE3_PROT:
 723                 cmd->reftag_seed = 0xffffffff;
 724                 break;
 725         case TARGET_DIF_TYPE2_PROT:
 726                 if (protect)
 727                         return TCM_INVALID_CDB_FIELD;
 728
 729                 cmd->reftag_seed = cmd->t_task_lba;
 730                 break;
 731         case TARGET_DIF_TYPE1_PROT:
 732                 cmd->reftag_seed = cmd->t_task_lba;
 733                 break;
 734         case TARGET_DIF_TYPE0_PROT:
 735                 /*
 736                  * See if the fabric supports T10-PI, and the session has been
 737                  * configured to allow export PROTECT=1 feature bit with backend
 738                  * devices that don't support T10-PI.
 739                  */
 740                 fabric_prot = is_write ?
 741                               !!(sp_ops & (TARGET_PROT_DOUT_PASS | TARGET_PROT_DOUT_STRIP)) :
 742                               !!(sp_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DIN_INSERT));
 743
 744                 if (fabric_prot && cmd->se_sess->sess_prot_type) {
 745                         pi_prot_type = cmd->se_sess->sess_prot_type;
 746                         break;
 747                 }
 748                 if (!protect)
 749                         return TCM_NO_SENSE;
 750                 /* Fallthrough */
 751         default:
 752                 pr_err("Unable to determine pi_prot_type for CDB: 0x%02x "
 753                        "PROTECT: 0x%02x\n", cdb[0], protect);
 754                 return TCM_INVALID_CDB_FIELD;
 755         }
 756
 757         if (sbc_set_prot_op_checks(protect, fabric_prot, pi_prot_type, is_write, cmd))
 758                 return TCM_INVALID_CDB_FIELD;
 759
 760         cmd->prot_type = pi_prot_type;
 761         cmd->prot_length = dev->prot_length * sectors;
 762
 763         /**
 764          * In case protection information exists over the wire
 765          * we modify command data length to describe pure data.
 766          * The actual transfer length is data length + protection
 767          * length
 768          **/
 769         if (protect)
 770                 cmd->data_length = sectors * dev->dev_attrib.block_size;
 771
 772         pr_debug("%s: prot_type=%d, data_length=%d, prot_length=%d "
 773                  "prot_op=%d prot_checks=%d\n",
 774                  __func__, cmd->prot_type, cmd->data_length, cmd->prot_length,
 775                  cmd->prot_op, cmd->prot_checks);
 776
 777         return TCM_NO_SENSE;
 778 }
 779
 780 static int
 781 sbc_check_dpofua(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb)
 782 {
 783         if (cdb[1] & 0x10) {
 784                 /* see explanation in spc_emulate_modesense */
 785                 if (!target_check_fua(dev)) {
 786                         pr_err("Got CDB: 0x%02x with DPO bit set, but device"
 787                                " does not advertise support for DPO\n", cdb[0]);
 788                         return -EINVAL;
 789                 }
 790         }
 791         if (cdb[1] & 0x8) {
 792                 if (!target_check_fua(dev)) {
 793                         pr_err("Got CDB: 0x%02x with FUA bit set, but device"
 794                                " does not advertise support for FUA write\n",
 795                                cdb[0]);
 796                         return -EINVAL;
 797                 }
 798                 cmd->se_cmd_flags |= SCF_FUA;
 799         }
 800         return 0;
 801 }
 802
 803 sense_reason_t
 804 sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 805 {
 806         struct se_device *dev = cmd->se_dev;
 807         unsigned char *cdb = cmd->t_task_cdb;
 808         unsigned int size;
 809         u32 sectors = 0;
 810         sense_reason_t ret;
 811
 812         cmd->protocol_data = ops;
 813
 814         switch (cdb[0]) {
 815         case READ_6:
 816                 sectors = transport_get_sectors_6(cdb);
 817                 cmd->t_task_lba = transport_lba_21(cdb);
 818                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 819                 cmd->execute_cmd = sbc_execute_rw;
 820                 break;
 821         case READ_10:
 822                 sectors = transport_get_sectors_10(cdb);
 823                 cmd->t_task_lba = transport_lba_32(cdb);
 824
 825                 if (sbc_check_dpofua(dev, cmd, cdb))
 826                         return TCM_INVALID_CDB_FIELD;
 827
 828                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 829                 if (ret)
 830                         return ret;
 831
 832                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 833                 cmd->execute_cmd = sbc_execute_rw;
 834                 break;
 835         case READ_12:
 836                 sectors = transport_get_sectors_12(cdb);
 837                 cmd->t_task_lba = transport_lba_32(cdb);
 838
 839                 if (sbc_check_dpofua(dev, cmd, cdb))
 840                         return TCM_INVALID_CDB_FIELD;
 841
 842                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 843                 if (ret)
 844                         return ret;
 845
 846                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 847                 cmd->execute_cmd = sbc_execute_rw;
 848                 break;
 849         case READ_16:
 850                 sectors = transport_get_sectors_16(cdb);
 851                 cmd->t_task_lba = transport_lba_64(cdb);
 852
 853                 if (sbc_check_dpofua(dev, cmd, cdb))
 854                         return TCM_INVALID_CDB_FIELD;
 855
 856                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 857                 if (ret)
 858                         return ret;
 859
 860                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 861                 cmd->execute_cmd = sbc_execute_rw;
 862                 break;
 863         case WRITE_6:
 864                 sectors = transport_get_sectors_6(cdb);
 865                 cmd->t_task_lba = transport_lba_21(cdb);
 866                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 867                 cmd->execute_cmd = sbc_execute_rw;
 868                 break;
 869         case WRITE_10:
 870         case WRITE_VERIFY:
 871                 sectors = transport_get_sectors_10(cdb);
 872                 cmd->t_task_lba = transport_lba_32(cdb);
 873
 874                 if (sbc_check_dpofua(dev, cmd, cdb))
 875                         return TCM_INVALID_CDB_FIELD;
 876
 877                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 878                 if (ret)
 879                         return ret;
 880
 881                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 882                 cmd->execute_cmd = sbc_execute_rw;
 883                 break;
 884         case WRITE_12:
 885                 sectors = transport_get_sectors_12(cdb);
 886                 cmd->t_task_lba = transport_lba_32(cdb);
 887
 888                 if (sbc_check_dpofua(dev, cmd, cdb))
 889                         return TCM_INVALID_CDB_FIELD;
 890
 891                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 892                 if (ret)
 893                         return ret;
 894
 895                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 896                 cmd->execute_cmd = sbc_execute_rw;
 897                 break;
 898         case WRITE_16:
 899         case WRITE_VERIFY_16:
 900                 sectors = transport_get_sectors_16(cdb);
 901                 cmd->t_task_lba = transport_lba_64(cdb);
 902
 903                 if (sbc_check_dpofua(dev, cmd, cdb))
 904                         return TCM_INVALID_CDB_FIELD;
 905
 906                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 907                 if (ret)
 908                         return ret;
 909
 910                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 911                 cmd->execute_cmd = sbc_execute_rw;
 912                 break;
 913         case XDWRITEREAD_10:
 914                 if (cmd->data_direction != DMA_TO_DEVICE ||
 915                     !(cmd->se_cmd_flags & SCF_BIDI))
 916                         return TCM_INVALID_CDB_FIELD;
 917                 sectors = transport_get_sectors_10(cdb);
 918
 919                 if (sbc_check_dpofua(dev, cmd, cdb))
 920                         return TCM_INVALID_CDB_FIELD;
 921
 922                 cmd->t_task_lba = transport_lba_32(cdb);
 923                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 924
 925                 /*
 926                  * Setup BIDI XOR callback to be run after I/O completion.
 927                  */
 928                 cmd->execute_cmd = sbc_execute_rw;
 929                 cmd->transport_complete_callback = &xdreadwrite_callback;
 930                 break;
 931         case VARIABLE_LENGTH_CMD:
 932         {
 933                 u16 service_action = get_unaligned_be16(&cdb[8]);
 934                 switch (service_action) {
 935                 case XDWRITEREAD_32:
 936                         sectors = transport_get_sectors_32(cdb);
 937
 938                         if (sbc_check_dpofua(dev, cmd, cdb))
 939                                 return TCM_INVALID_CDB_FIELD;
 940                         /*
 941                          * Use WRITE_32 and READ_32 opcodes for the emulated
 942                          * XDWRITE_READ_32 logic.
 943                          */
 944                         cmd->t_task_lba = transport_lba_64_ext(cdb);
 945                         cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 946
 947                         /*
 948                          * Setup BIDI XOR callback to be run during after I/O
 949                          * completion.
 950                          */
 951                         cmd->execute_cmd = sbc_execute_rw;
 952                         cmd->transport_complete_callback = &xdreadwrite_callback;
 953                         break;
 954                 case WRITE_SAME_32:
 955                         sectors = transport_get_sectors_32(cdb);
 956                         if (!sectors) {
 957                                 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
 958                                        " supported\n");
 959                                 return TCM_INVALID_CDB_FIELD;
 960                         }
 961
 962                         size = sbc_get_size(cmd, 1);
 963                         cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
 964
 965                         ret = sbc_setup_write_same(cmd, &cdb[10], ops);
 966                         if (ret)
 967                                 return ret;
 968                         break;
 969                 default:
 970                         pr_err("VARIABLE_LENGTH_CMD service action"
 971                                 " 0x%04x not supported\n", service_action);
 972                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 973                 }
 974                 break;
 975         }
 976         case COMPARE_AND_WRITE:
 977                 if (!dev->dev_attrib.emulate_caw) {
 978                         pr_err_ratelimited("se_device %s/%s (vpd_unit_serial %s) reject COMPARE_AND_WRITE\n",
 979                                            dev->se_hba->backend->ops->name,
 980                                            config_item_name(&dev->dev_group.cg_item),
 981                                            dev->t10_wwn.unit_serial);
 982                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 983                 }
 984                 sectors = cdb[13];
 985                 /*
 986                  * Currently enforce COMPARE_AND_WRITE for a single sector
 987                  */
 988                 if (sectors > 1) {
 989                         pr_err("COMPARE_AND_WRITE contains NoLB: %u greater"
 990                                " than 1\n", sectors);
 991                         return TCM_INVALID_CDB_FIELD;
 992                 }
 993                 if (sbc_check_dpofua(dev, cmd, cdb))
 994                         return TCM_INVALID_CDB_FIELD;
 995
 996                 /*
 997                  * Double size because we have two buffers, note that
 998                  * zero is not an error..
 999                  */
1000                 size = 2 * sbc_get_size(cmd, sectors);
1001                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1002                 cmd->t_task_nolb = sectors;
1003                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE;
1004                 cmd->execute_cmd = sbc_compare_and_write;
1005                 cmd->transport_complete_callback = compare_and_write_callback;
1006                 break;
1007         case READ_CAPACITY:
1008                 size = READ_CAP_LEN;
1009                 cmd->execute_cmd = sbc_emulate_readcapacity;
1010                 break;
1011         case SERVICE_ACTION_IN_16:
1012                 switch (cmd->t_task_cdb[1] & 0x1f) {
1013                 case SAI_READ_CAPACITY_16:
1014                         cmd->execute_cmd = sbc_emulate_readcapacity_16;
1015                         break;
1016                 case SAI_REPORT_REFERRALS:
1017                         cmd->execute_cmd = target_emulate_report_referrals;
1018                         break;
1019                 default:
1020                         pr_err("Unsupported SA: 0x%02x\n",
1021                                 cmd->t_task_cdb[1] & 0x1f);
1022                         return TCM_INVALID_CDB_FIELD;
1023                 }
1024                 size = get_unaligned_be32(&cdb[10]);
1025                 break;
1026         case SYNCHRONIZE_CACHE:
1027         case SYNCHRONIZE_CACHE_16:
1028                 if (cdb[0] == SYNCHRONIZE_CACHE) {
1029                         sectors = transport_get_sectors_10(cdb);
1030                         cmd->t_task_lba = transport_lba_32(cdb);
1031                 } else {
1032                         sectors = transport_get_sectors_16(cdb);
1033                         cmd->t_task_lba = transport_lba_64(cdb);
1034                 }
1035                 if (ops->execute_sync_cache) {
1036                         cmd->execute_cmd = ops->execute_sync_cache;
1037                         goto check_lba;
1038                 }
1039                 size = 0;
1040                 cmd->execute_cmd = sbc_emulate_noop;
1041                 break;
1042         case UNMAP:
1043                 if (!ops->execute_unmap)
1044                         return TCM_UNSUPPORTED_SCSI_OPCODE;
1045
1046                 if (!dev->dev_attrib.emulate_tpu) {
1047                         pr_err("Got UNMAP, but backend device has"
1048                                " emulate_tpu disabled\n");
1049                         return TCM_UNSUPPORTED_SCSI_OPCODE;
1050                 }
1051                 size = get_unaligned_be16(&cdb[7]);
1052                 cmd->execute_cmd = sbc_execute_unmap;
1053                 break;
1054         case WRITE_SAME_16:
1055                 sectors = transport_get_sectors_16(cdb);
1056                 if (!sectors) {
1057                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1058                         return TCM_INVALID_CDB_FIELD;
1059                 }
1060
1061                 size = sbc_get_size(cmd, 1);
1062                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1063
1064                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1065                 if (ret)
1066                         return ret;
1067                 break;
1068         case WRITE_SAME:
1069                 sectors = transport_get_sectors_10(cdb);
1070                 if (!sectors) {
1071                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1072                         return TCM_INVALID_CDB_FIELD;
1073                 }
1074
1075                 size = sbc_get_size(cmd, 1);
1076                 cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
1077
1078                 /*
1079                  * Follow sbcr26 with WRITE_SAME (10) and check for the existence
1080                  * of byte 1 bit 3 UNMAP instead of original reserved field
1081                  */
1082                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1083                 if (ret)
1084                         return ret;
1085                 break;
1086         case VERIFY:
1087         case VERIFY_16:
1088                 size = 0;
1089                 if (cdb[0] == VERIFY) {
1090                         sectors = transport_get_sectors_10(cdb);
1091                         cmd->t_task_lba = transport_lba_32(cdb);
1092                 } else {
1093                         sectors = transport_get_sectors_16(cdb);
1094                         cmd->t_task_lba = transport_lba_64(cdb);
1095                 }
1096                 cmd->execute_cmd = sbc_emulate_noop;
1097                 goto check_lba;
1098         case REZERO_UNIT:
1099         case SEEK_6:
1100         case SEEK_10:
1101                 /*
1102                  * There are still clients out there which use these old SCSI-2
1103                  * commands. This mainly happens when running VMs with legacy
1104                  * guest systems, connected via SCSI command pass-through to
1105                  * iSCSI targets. Make them happy and return status GOOD.
1106                  */
1107                 size = 0;
1108                 cmd->execute_cmd = sbc_emulate_noop;
1109                 break;
1110         case START_STOP:
1111                 size = 0;
1112                 cmd->execute_cmd = sbc_emulate_startstop;
1113                 break;
1114         default:
1115                 ret = spc_parse_cdb(cmd, &size);
1116                 if (ret)
1117                         return ret;
1118         }
1119
1120         /* reject any command that we don't have a handler for */
1121         if (!cmd->execute_cmd)
1122                 return TCM_UNSUPPORTED_SCSI_OPCODE;
1123
1124         if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1125                 unsigned long long end_lba;
1126 check_lba:
1127                 end_lba = dev->transport->get_blocks(dev) + 1;
1128                 if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
1129                     ((cmd->t_task_lba + sectors) > end_lba)) {
1130                         pr_err("cmd exceeds last lba %llu "
1131                                 "(lba %llu, sectors %u)\n",
1132                                 end_lba, cmd->t_task_lba, sectors);
1133                         return TCM_ADDRESS_OUT_OF_RANGE;
1134                 }
1135
1136                 if (!(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE))
1137                         size = sbc_get_size(cmd, sectors);
1138         }
1139
1140         return target_cmd_size_check(cmd, size);
1141 }
1142 EXPORT_SYMBOL(sbc_parse_cdb);
1143
1144 u32 sbc_get_device_type(struct se_device *dev)
1145 {
1146         return TYPE_DISK;
1147 }
1148 EXPORT_SYMBOL(sbc_get_device_type);
1149
1150 static sense_reason_t
1151 sbc_execute_unmap(struct se_cmd *cmd)
1152 {
1153         struct sbc_ops *ops = cmd->protocol_data;
1154         struct se_device *dev = cmd->se_dev;
1155         unsigned char *buf, *ptr = NULL;
1156         sector_t lba;
1157         int size;
1158         u32 range;
1159         sense_reason_t ret = 0;
1160         int dl, bd_dl;
1161
1162         /* We never set ANC_SUP */
1163         if (cmd->t_task_cdb[1])
1164                 return TCM_INVALID_CDB_FIELD;
1165
1166         if (cmd->data_length == 0) {
1167                 target_complete_cmd(cmd, SAM_STAT_GOOD);
1168                 return 0;
1169         }
1170
1171         if (cmd->data_length < 8) {
1172                 pr_warn("UNMAP parameter list length %u too small\n",
1173                         cmd->data_length);
1174                 return TCM_PARAMETER_LIST_LENGTH_ERROR;
1175         }
1176
1177         buf = transport_kmap_data_sg(cmd);
1178         if (!buf)
1179                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1180
1181         dl = get_unaligned_be16(&buf[0]);
1182         bd_dl = get_unaligned_be16(&buf[2]);
1183
1184         size = cmd->data_length - 8;
1185         if (bd_dl > size)
1186                 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
1187                         cmd->data_length, bd_dl);
1188         else
1189                 size = bd_dl;
1190
1191         if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
1192                 ret = TCM_INVALID_PARAMETER_LIST;
1193                 goto err;
1194         }
1195
1196         /* First UNMAP block descriptor starts at 8 byte offset */
1197         ptr = &buf[8];
1198         pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
1199                 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
1200
1201         while (size >= 16) {
1202                 lba = get_unaligned_be64(&ptr[0]);
1203                 range = get_unaligned_be32(&ptr[8]);
1204                 pr_debug("UNMAP: Using lba: %llu and range: %u\n",
1205                                  (unsigned long long)lba, range);
1206
1207                 if (range > dev->dev_attrib.max_unmap_lba_count) {
1208                         ret = TCM_INVALID_PARAMETER_LIST;
1209                         goto err;
1210                 }
1211
1212                 if (lba + range > dev->transport->get_blocks(dev) + 1) {
1213                         ret = TCM_ADDRESS_OUT_OF_RANGE;
1214                         goto err;
1215                 }
1216
1217                 if (range) {
1218                         ret = ops->execute_unmap(cmd, lba, range);
1219                         if (ret)
1220                                 goto err;
1221                 }
1222
1223                 ptr += 16;
1224                 size -= 16;
1225         }
1226
1227 err:
1228         transport_kunmap_data_sg(cmd);
1229         if (!ret)
1230                 target_complete_cmd(cmd, GOOD);
1231         return ret;
1232 }
1233
1234 void
1235 sbc_dif_generate(struct se_cmd *cmd)
1236 {
1237         struct se_device *dev = cmd->se_dev;
1238         struct t10_pi_tuple *sdt;
1239         struct scatterlist *dsg = cmd->t_data_sg, *psg;
1240         sector_t sector = cmd->t_task_lba;
1241         void *daddr, *paddr;
1242         int i, j, offset = 0;
1243         unsigned int block_size = dev->dev_attrib.block_size;
1244
1245         for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1246                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1247                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1248
1249                 for (j = 0; j < psg->length;
1250                                 j += sizeof(*sdt)) {
1251                         __u16 crc;
1252                         unsigned int avail;
1253
1254                         if (offset >= dsg->length) {
1255                                 offset -= dsg->length;
1256                                 kunmap_atomic(daddr - dsg->offset);
1257                                 dsg = sg_next(dsg);
1258                                 if (!dsg) {
1259                                         kunmap_atomic(paddr - psg->offset);
1260                                         return;
1261                                 }
1262                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1263                         }
1264
1265                         sdt = paddr + j;
1266                         avail = min(block_size, dsg->length - offset);
1267                         crc = crc_t10dif(daddr + offset, avail);
1268                         if (avail < block_size) {
1269                                 kunmap_atomic(daddr - dsg->offset);
1270                                 dsg = sg_next(dsg);
1271                                 if (!dsg) {
1272                                         kunmap_atomic(paddr - psg->offset);
1273                                         return;
1274                                 }
1275                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1276                                 offset = block_size - avail;
1277                                 crc = crc_t10dif_update(crc, daddr, offset);
1278                         } else {
1279                                 offset += block_size;
1280                         }
1281
1282                         sdt->guard_tag = cpu_to_be16(crc);
1283                         if (cmd->prot_type == TARGET_DIF_TYPE1_PROT)
1284                                 sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
1285                         sdt->app_tag = 0;
1286
1287                         pr_debug("DIF %s INSERT sector: %llu guard_tag: 0x%04x"
1288                                  " app_tag: 0x%04x ref_tag: %u\n",
1289                                  (cmd->data_direction == DMA_TO_DEVICE) ?
1290                                  "WRITE" : "READ", (unsigned long long)sector,
1291                                  sdt->guard_tag, sdt->app_tag,
1292                                  be32_to_cpu(sdt->ref_tag));
1293
1294                         sector++;
1295                 }
1296
1297                 kunmap_atomic(daddr - dsg->offset);
1298                 kunmap_atomic(paddr - psg->offset);
1299         }
1300 }
1301
1302 static sense_reason_t
1303 sbc_dif_v1_verify(struct se_cmd *cmd, struct t10_pi_tuple *sdt,
1304                   __u16 crc, sector_t sector, unsigned int ei_lba)
1305 {
1306         __be16 csum;
1307
1308         if (!(cmd->prot_checks & TARGET_DIF_CHECK_GUARD))
1309                 goto check_ref;
1310
1311         csum = cpu_to_be16(crc);
1312
1313         if (sdt->guard_tag != csum) {
1314                 pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x"
1315                         " csum 0x%04x\n", (unsigned long long)sector,
1316                         be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
1317                 return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
1318         }
1319
1320 check_ref:
1321         if (!(cmd->prot_checks & TARGET_DIF_CHECK_REFTAG))
1322                 return 0;
1323
1324         if (cmd->prot_type == TARGET_DIF_TYPE1_PROT &&
1325             be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
1326                 pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x"
1327                        " sector MSB: 0x%08x\n", (unsigned long long)sector,
1328                        be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff));
1329                 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1330         }
1331
1332         if (cmd->prot_type == TARGET_DIF_TYPE2_PROT &&
1333             be32_to_cpu(sdt->ref_tag) != ei_lba) {
1334                 pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x"
1335                        " ei_lba: 0x%08x\n", (unsigned long long)sector,
1336                         be32_to_cpu(sdt->ref_tag), ei_lba);
1337                 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1338         }
1339
1340         return 0;
1341 }
1342
1343 void sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read,
1344                        struct scatterlist *sg, int sg_off)
1345 {
1346         struct se_device *dev = cmd->se_dev;
1347         struct scatterlist *psg;
1348         void *paddr, *addr;
1349         unsigned int i, len, left;
1350         unsigned int offset = sg_off;
1351
1352         if (!sg)
1353                 return;
1354
1355         left = sectors * dev->prot_length;
1356
1357         for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1358                 unsigned int psg_len, copied = 0;
1359
1360                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1361                 psg_len = min(left, psg->length);
1362                 while (psg_len) {
1363                         len = min(psg_len, sg->length - offset);
1364                         addr = kmap_atomic(sg_page(sg)) + sg->offset + offset;
1365
1366                         if (read)
1367                                 memcpy(paddr + copied, addr, len);
1368                         else
1369                                 memcpy(addr, paddr + copied, len);
1370
1371                         left -= len;
1372                         offset += len;
1373                         copied += len;
1374                         psg_len -= len;
1375
1376                         kunmap_atomic(addr - sg->offset - offset);
1377
1378                         if (offset >= sg->length) {
1379                                 sg = sg_next(sg);
1380                                 offset = 0;
1381                         }
1382                 }
1383                 kunmap_atomic(paddr - psg->offset);
1384         }
1385 }
1386 EXPORT_SYMBOL(sbc_dif_copy_prot);
1387
1388 sense_reason_t
1389 sbc_dif_verify(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1390                unsigned int ei_lba, struct scatterlist *psg, int psg_off)
1391 {
1392         struct se_device *dev = cmd->se_dev;
1393         struct t10_pi_tuple *sdt;
1394         struct scatterlist *dsg = cmd->t_data_sg;
1395         sector_t sector = start;
1396         void *daddr, *paddr;
1397         int i;
1398         sense_reason_t rc;
1399         int dsg_off = 0;
1400         unsigned int block_size = dev->dev_attrib.block_size;
1401
1402         for (; psg && sector < start + sectors; psg = sg_next(psg)) {
1403                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1404                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1405
1406                 for (i = psg_off; i < psg->length &&
1407                                 sector < start + sectors;
1408                                 i += sizeof(*sdt)) {
1409                         __u16 crc;
1410                         unsigned int avail;
1411
1412                         if (dsg_off >= dsg->length) {
1413                                 dsg_off -= dsg->length;
1414                                 kunmap_atomic(daddr - dsg->offset);
1415                                 dsg = sg_next(dsg);
1416                                 if (!dsg) {
1417                                         kunmap_atomic(paddr - psg->offset);
1418                                         return 0;
1419                                 }
1420                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1421                         }
1422
1423                         sdt = paddr + i;
1424
1425                         pr_debug("DIF READ sector: %llu guard_tag: 0x%04x"
1426                                  " app_tag: 0x%04x ref_tag: %u\n",
1427                                  (unsigned long long)sector, sdt->guard_tag,
1428                                  sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1429
1430                         if (sdt->app_tag == T10_PI_APP_ESCAPE) {
1431                                 dsg_off += block_size;
1432                                 goto next;
1433                         }
1434
1435                         avail = min(block_size, dsg->length - dsg_off);
1436                         crc = crc_t10dif(daddr + dsg_off, avail);
1437                         if (avail < block_size) {
1438                                 kunmap_atomic(daddr - dsg->offset);
1439                                 dsg = sg_next(dsg);
1440                                 if (!dsg) {
1441                                         kunmap_atomic(paddr - psg->offset);
1442                                         return 0;
1443                                 }
1444                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1445                                 dsg_off = block_size - avail;
1446                                 crc = crc_t10dif_update(crc, daddr, dsg_off);
1447                         } else {
1448                                 dsg_off += block_size;
1449                         }
1450
1451                         rc = sbc_dif_v1_verify(cmd, sdt, crc, sector, ei_lba);
1452                         if (rc) {
1453                                 kunmap_atomic(daddr - dsg->offset);
1454                                 kunmap_atomic(paddr - psg->offset);
1455                                 cmd->bad_sector = sector;
1456                                 return rc;
1457                         }
1458 next:
1459                         sector++;
1460                         ei_lba++;
1461                 }
1462
1463                 psg_off = 0;
1464                 kunmap_atomic(daddr - dsg->offset);
1465                 kunmap_atomic(paddr - psg->offset);
1466         }
1467
1468         return 0;
1469 }
1470 EXPORT_SYMBOL(sbc_dif_verify);