drivers/target/target_core_sbc.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * SCSI Block Commands (SBC) parsing and emulation.
   4  *
   5  * (c) Copyright 2002-2013 Datera, Inc.
   6  *
   7  * Nicholas A. Bellinger <nab@kernel.org>
   8  */
   9
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12 #include <linux/ratelimit.h>
  13 #include <linux/crc-t10dif.h>
  14 #include <linux/t10-pi.h>
  15 #include <asm/unaligned.h>
  16 #include <scsi/scsi_proto.h>
  17 #include <scsi/scsi_tcq.h>
  18
  19 #include <target/target_core_base.h>
  20 #include <target/target_core_backend.h>
  21 #include <target/target_core_fabric.h>
  22
  23 #include "target_core_internal.h"
  24 #include "target_core_ua.h"
  25 #include "target_core_alua.h"
  26
  27 static sense_reason_t
  28 sbc_check_prot(struct se_device *, struct se_cmd *, unsigned char *, u32, bool);
  29 static sense_reason_t sbc_execute_unmap(struct se_cmd *cmd);
  30
  31 static sense_reason_t
  32 sbc_emulate_readcapacity(struct se_cmd *cmd)
  33 {
  34         struct se_device *dev = cmd->se_dev;
  35         unsigned char *cdb = cmd->t_task_cdb;
  36         unsigned long long blocks_long = dev->transport->get_blocks(dev);
  37         unsigned char *rbuf;
  38         unsigned char buf[8];
  39         u32 blocks;
  40
  41         /*
  42          * SBC-2 says:
  43          *   If the PMI bit is set to zero and the LOGICAL BLOCK
  44          *   ADDRESS field is not set to zero, the device server shall
  45          *   terminate the command with CHECK CONDITION status with
  46          *   the sense key set to ILLEGAL REQUEST and the additional
  47          *   sense code set to INVALID FIELD IN CDB.
  48          *
  49          * In SBC-3, these fields are obsolete, but some SCSI
  50          * compliance tests actually check this, so we might as well
  51          * follow SBC-2.
  52          */
  53         if (!(cdb[8] & 1) && !!(cdb[2] | cdb[3] | cdb[4] | cdb[5]))
  54                 return TCM_INVALID_CDB_FIELD;
  55
  56         if (blocks_long >= 0x00000000ffffffff)
  57                 blocks = 0xffffffff;
  58         else
  59                 blocks = (u32)blocks_long;
  60
  61         put_unaligned_be32(blocks, &buf[0]);
  62         put_unaligned_be32(dev->dev_attrib.block_size, &buf[4]);
  63
  64         rbuf = transport_kmap_data_sg(cmd);
  65         if (rbuf) {
  66                 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
  67                 transport_kunmap_data_sg(cmd);
  68         }
  69
  70         target_complete_cmd_with_length(cmd, GOOD, 8);
  71         return 0;
  72 }
  73
  74 static sense_reason_t
  75 sbc_emulate_readcapacity_16(struct se_cmd *cmd)
  76 {
  77         struct se_device *dev = cmd->se_dev;
  78         struct se_session *sess = cmd->se_sess;
  79         int pi_prot_type = dev->dev_attrib.pi_prot_type;
  80
  81         unsigned char *rbuf;
  82         unsigned char buf[32];
  83         unsigned long long blocks = dev->transport->get_blocks(dev);
  84
  85         memset(buf, 0, sizeof(buf));
  86         put_unaligned_be64(blocks, &buf[0]);
  87         put_unaligned_be32(dev->dev_attrib.block_size, &buf[8]);
  88         /*
  89          * Set P_TYPE and PROT_EN bits for DIF support
  90          */
  91         if (sess->sup_prot_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS)) {
  92                 /*
  93                  * Only override a device's pi_prot_type if no T10-PI is
  94                  * available, and sess_prot_type has been explicitly enabled.
  95                  */
  96                 if (!pi_prot_type)
  97                         pi_prot_type = sess->sess_prot_type;
  98
  99                 if (pi_prot_type)
 100                         buf[12] = (pi_prot_type - 1) << 1 | 0x1;
 101         }
 102
 103         if (dev->transport->get_lbppbe)
 104                 buf[13] = dev->transport->get_lbppbe(dev) & 0x0f;
 105
 106         if (dev->transport->get_alignment_offset_lbas) {
 107                 u16 lalba = dev->transport->get_alignment_offset_lbas(dev);
 108
 109                 put_unaligned_be16(lalba, &buf[14]);
 110         }
 111
 112         /*
 113          * Set Thin Provisioning Enable bit following sbc3r22 in section
 114          * READ CAPACITY (16) byte 14 if emulate_tpu or emulate_tpws is enabled.
 115          */
 116         if (dev->dev_attrib.emulate_tpu || dev->dev_attrib.emulate_tpws) {
 117                 buf[14] |= 0x80;
 118
 119                 /*
 120                  * LBPRZ signifies that zeroes will be read back from an LBA after
 121                  * an UNMAP or WRITE SAME w/ unmap bit (sbc3r36 5.16.2)
 122                  */
 123                 if (dev->dev_attrib.unmap_zeroes_data)
 124                         buf[14] |= 0x40;
 125         }
 126
 127         rbuf = transport_kmap_data_sg(cmd);
 128         if (rbuf) {
 129                 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
 130                 transport_kunmap_data_sg(cmd);
 131         }
 132
 133         target_complete_cmd_with_length(cmd, GOOD, 32);
 134         return 0;
 135 }
 136
 137 static sense_reason_t
 138 sbc_emulate_startstop(struct se_cmd *cmd)
 139 {
 140         unsigned char *cdb = cmd->t_task_cdb;
 141
 142         /*
 143          * See sbc3r36 section 5.25
 144          * Immediate bit should be set since there is nothing to complete
 145          * POWER CONDITION MODIFIER 0h
 146          */
 147         if (!(cdb[1] & 1) || cdb[2] || cdb[3])
 148                 return TCM_INVALID_CDB_FIELD;
 149
 150         /*
 151          * See sbc3r36 section 5.25
 152          * POWER CONDITION 0h START_VALID - process START and LOEJ
 153          */
 154         if (cdb[4] >> 4 & 0xf)
 155                 return TCM_INVALID_CDB_FIELD;
 156
 157         /*
 158          * See sbc3r36 section 5.25
 159          * LOEJ 0h - nothing to load or unload
 160          * START 1h - we are ready
 161          */
 162         if (!(cdb[4] & 1) || (cdb[4] & 2) || (cdb[4] & 4))
 163                 return TCM_INVALID_CDB_FIELD;
 164
 165         target_complete_cmd(cmd, SAM_STAT_GOOD);
 166         return 0;
 167 }
 168
 169 sector_t sbc_get_write_same_sectors(struct se_cmd *cmd)
 170 {
 171         u32 num_blocks;
 172
 173         if (cmd->t_task_cdb[0] == WRITE_SAME)
 174                 num_blocks = get_unaligned_be16(&cmd->t_task_cdb[7]);
 175         else if (cmd->t_task_cdb[0] == WRITE_SAME_16)
 176                 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[10]);
 177         else /* WRITE_SAME_32 via VARIABLE_LENGTH_CMD */
 178                 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[28]);
 179
 180         /*
 181          * Use the explicit range when non zero is supplied, otherwise calculate
 182          * the remaining range based on ->get_blocks() - starting LBA.
 183          */
 184         if (num_blocks)
 185                 return num_blocks;
 186
 187         return cmd->se_dev->transport->get_blocks(cmd->se_dev) -
 188                 cmd->t_task_lba + 1;
 189 }
 190 EXPORT_SYMBOL(sbc_get_write_same_sectors);
 191
 192 static sense_reason_t
 193 sbc_execute_write_same_unmap(struct se_cmd *cmd)
 194 {
 195         struct sbc_ops *ops = cmd->protocol_data;
 196         sector_t nolb = sbc_get_write_same_sectors(cmd);
 197         sense_reason_t ret;
 198
 199         if (nolb) {
 200                 ret = ops->execute_unmap(cmd, cmd->t_task_lba, nolb);
 201                 if (ret)
 202                         return ret;
 203         }
 204
 205         target_complete_cmd(cmd, GOOD);
 206         return 0;
 207 }
 208
 209 static sense_reason_t
 210 sbc_emulate_noop(struct se_cmd *cmd)
 211 {
 212         target_complete_cmd(cmd, GOOD);
 213         return 0;
 214 }
 215
 216 static inline u32 sbc_get_size(struct se_cmd *cmd, u32 sectors)
 217 {
 218         return cmd->se_dev->dev_attrib.block_size * sectors;
 219 }
 220
 221 static inline u32 transport_get_sectors_6(unsigned char *cdb)
 222 {
 223         /*
 224          * Use 8-bit sector value.  SBC-3 says:
 225          *
 226          *   A TRANSFER LENGTH field set to zero specifies that 256
 227          *   logical blocks shall be written.  Any other value
 228          *   specifies the number of logical blocks that shall be
 229          *   written.
 230          */
 231         return cdb[4] ? : 256;
 232 }
 233
 234 static inline u32 transport_get_sectors_10(unsigned char *cdb)
 235 {
 236         return get_unaligned_be16(&cdb[7]);
 237 }
 238
 239 static inline u32 transport_get_sectors_12(unsigned char *cdb)
 240 {
 241         return get_unaligned_be32(&cdb[6]);
 242 }
 243
 244 static inline u32 transport_get_sectors_16(unsigned char *cdb)
 245 {
 246         return get_unaligned_be32(&cdb[10]);
 247 }
 248
 249 /*
 250  * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
 251  */
 252 static inline u32 transport_get_sectors_32(unsigned char *cdb)
 253 {
 254         return get_unaligned_be32(&cdb[28]);
 255
 256 }
 257
 258 static inline u32 transport_lba_21(unsigned char *cdb)
 259 {
 260         return get_unaligned_be24(&cdb[1]) & 0x1fffff;
 261 }
 262
 263 static inline u32 transport_lba_32(unsigned char *cdb)
 264 {
 265         return get_unaligned_be32(&cdb[2]);
 266 }
 267
 268 static inline unsigned long long transport_lba_64(unsigned char *cdb)
 269 {
 270         return get_unaligned_be64(&cdb[2]);
 271 }
 272
 273 /*
 274  * For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs
 275  */
 276 static inline unsigned long long transport_lba_64_ext(unsigned char *cdb)
 277 {
 278         return get_unaligned_be64(&cdb[12]);
 279 }
 280
 281 static sense_reason_t
 282 sbc_setup_write_same(struct se_cmd *cmd, unsigned char *flags, struct sbc_ops *ops)
 283 {
 284         struct se_device *dev = cmd->se_dev;
 285         sector_t end_lba = dev->transport->get_blocks(dev) + 1;
 286         unsigned int sectors = sbc_get_write_same_sectors(cmd);
 287         sense_reason_t ret;
 288
 289         if ((flags[0] & 0x04) || (flags[0] & 0x02)) {
 290                 pr_err("WRITE_SAME PBDATA and LBDATA"
 291                         " bits not supported for Block Discard"
 292                         " Emulation\n");
 293                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 294         }
 295         if (sectors > cmd->se_dev->dev_attrib.max_write_same_len) {
 296                 pr_warn("WRITE_SAME sectors: %u exceeds max_write_same_len: %u\n",
 297                         sectors, cmd->se_dev->dev_attrib.max_write_same_len);
 298                 return TCM_INVALID_CDB_FIELD;
 299         }
 300         /*
 301          * Sanity check for LBA wrap and request past end of device.
 302          */
 303         if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
 304             ((cmd->t_task_lba + sectors) > end_lba)) {
 305                 pr_err("WRITE_SAME exceeds last lba %llu (lba %llu, sectors %u)\n",
 306                        (unsigned long long)end_lba, cmd->t_task_lba, sectors);
 307                 return TCM_ADDRESS_OUT_OF_RANGE;
 308         }
 309
 310         /* We always have ANC_SUP == 0 so setting ANCHOR is always an error */
 311         if (flags[0] & 0x10) {
 312                 pr_warn("WRITE SAME with ANCHOR not supported\n");
 313                 return TCM_INVALID_CDB_FIELD;
 314         }
 315         /*
 316          * Special case for WRITE_SAME w/ UNMAP=1 that ends up getting
 317          * translated into block discard requests within backend code.
 318          */
 319         if (flags[0] & 0x08) {
 320                 if (!ops->execute_unmap)
 321                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 322
 323                 if (!dev->dev_attrib.emulate_tpws) {
 324                         pr_err("Got WRITE_SAME w/ UNMAP=1, but backend device"
 325                                " has emulate_tpws disabled\n");
 326                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 327                 }
 328                 cmd->execute_cmd = sbc_execute_write_same_unmap;
 329                 return 0;
 330         }
 331         if (!ops->execute_write_same)
 332                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 333
 334         ret = sbc_check_prot(dev, cmd, &cmd->t_task_cdb[0], sectors, true);
 335         if (ret)
 336                 return ret;
 337
 338         cmd->execute_cmd = ops->execute_write_same;
 339         return 0;
 340 }
 341
 342 static sense_reason_t xdreadwrite_callback(struct se_cmd *cmd, bool success,
 343                                            int *post_ret)
 344 {
 345         unsigned char *buf, *addr;
 346         struct scatterlist *sg;
 347         unsigned int offset;
 348         sense_reason_t ret = TCM_NO_SENSE;
 349         int i, count;
 350
 351         if (!success)
 352                 return 0;
 353
 354         /*
 355          * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
 356          *
 357          * 1) read the specified logical block(s);
 358          * 2) transfer logical blocks from the data-out buffer;
 359          * 3) XOR the logical blocks transferred from the data-out buffer with
 360          *    the logical blocks read, storing the resulting XOR data in a buffer;
 361          * 4) if the DISABLE WRITE bit is set to zero, then write the logical
 362          *    blocks transferred from the data-out buffer; and
 363          * 5) transfer the resulting XOR data to the data-in buffer.
 364          */
 365         buf = kmalloc(cmd->data_length, GFP_KERNEL);
 366         if (!buf) {
 367                 pr_err("Unable to allocate xor_callback buf\n");
 368                 return TCM_OUT_OF_RESOURCES;
 369         }
 370         /*
 371          * Copy the scatterlist WRITE buffer located at cmd->t_data_sg
 372          * into the locally allocated *buf
 373          */
 374         sg_copy_to_buffer(cmd->t_data_sg,
 375                           cmd->t_data_nents,
 376                           buf,
 377                           cmd->data_length);
 378
 379         /*
 380          * Now perform the XOR against the BIDI read memory located at
 381          * cmd->t_mem_bidi_list
 382          */
 383
 384         offset = 0;
 385         for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
 386                 addr = kmap_atomic(sg_page(sg));
 387                 if (!addr) {
 388                         ret = TCM_OUT_OF_RESOURCES;
 389                         goto out;
 390                 }
 391
 392                 for (i = 0; i < sg->length; i++)
 393                         *(addr + sg->offset + i) ^= *(buf + offset + i);
 394
 395                 offset += sg->length;
 396                 kunmap_atomic(addr);
 397         }
 398
 399 out:
 400         kfree(buf);
 401         return ret;
 402 }
 403
 404 static sense_reason_t
 405 sbc_execute_rw(struct se_cmd *cmd)
 406 {
 407         struct sbc_ops *ops = cmd->protocol_data;
 408
 409         return ops->execute_rw(cmd, cmd->t_data_sg, cmd->t_data_nents,
 410                                cmd->data_direction);
 411 }
 412
 413 static sense_reason_t compare_and_write_post(struct se_cmd *cmd, bool success,
 414                                              int *post_ret)
 415 {
 416         struct se_device *dev = cmd->se_dev;
 417         sense_reason_t ret = TCM_NO_SENSE;
 418
 419         spin_lock_irq(&cmd->t_state_lock);
 420         if (success) {
 421                 *post_ret = 1;
 422
 423                 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION)
 424                         ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 425         }
 426         spin_unlock_irq(&cmd->t_state_lock);
 427
 428         /*
 429          * Unlock ->caw_sem originally obtained during sbc_compare_and_write()
 430          * before the original READ I/O submission.
 431          */
 432         up(&dev->caw_sem);
 433
 434         return ret;
 435 }
 436
 437 /*
 438  * compare @cmp_len bytes of @read_sgl with @cmp_sgl. On miscompare, fill
 439  * @miscmp_off and return TCM_MISCOMPARE_VERIFY.
 440  */
 441 static sense_reason_t
 442 compare_and_write_do_cmp(struct scatterlist *read_sgl, unsigned int read_nents,
 443                          struct scatterlist *cmp_sgl, unsigned int cmp_nents,
 444                          unsigned int cmp_len, unsigned int *miscmp_off)
 445 {
 446         unsigned char *buf = NULL;
 447         struct scatterlist *sg;
 448         sense_reason_t ret;
 449         unsigned int offset;
 450         size_t rc;
 451         int sg_cnt;
 452
 453         buf = kzalloc(cmp_len, GFP_KERNEL);
 454         if (!buf) {
 455                 ret = TCM_OUT_OF_RESOURCES;
 456                 goto out;
 457         }
 458
 459         rc = sg_copy_to_buffer(cmp_sgl, cmp_nents, buf, cmp_len);
 460         if (!rc) {
 461                 pr_err("sg_copy_to_buffer() failed for compare_and_write\n");
 462                 ret = TCM_OUT_OF_RESOURCES;
 463                 goto out;
 464         }
 465         /*
 466          * Compare SCSI READ payload against verify payload
 467          */
 468         offset = 0;
 469         ret = TCM_NO_SENSE;
 470         for_each_sg(read_sgl, sg, read_nents, sg_cnt) {
 471                 unsigned int len = min(sg->length, cmp_len);
 472                 unsigned char *addr = kmap_atomic(sg_page(sg));
 473
 474                 if (memcmp(addr, buf + offset, len)) {
 475                         unsigned int i;
 476
 477                         for (i = 0; i < len && addr[i] == buf[offset + i]; i++)
 478                                 ;
 479                         *miscmp_off = offset + i;
 480                         pr_warn("Detected MISCOMPARE at offset %u\n",
 481                                 *miscmp_off);
 482                         ret = TCM_MISCOMPARE_VERIFY;
 483                 }
 484                 kunmap_atomic(addr);
 485                 if (ret != TCM_NO_SENSE)
 486                         goto out;
 487
 488                 offset += len;
 489                 cmp_len -= len;
 490                 if (!cmp_len)
 491                         break;
 492         }
 493         pr_debug("COMPARE AND WRITE read data matches compare data\n");
 494 out:
 495         kfree(buf);
 496         return ret;
 497 }
 498
 499 static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool success,
 500                                                  int *post_ret)
 501 {
 502         struct se_device *dev = cmd->se_dev;
 503         struct sg_table write_tbl = { };
 504         struct scatterlist *write_sg;
 505         struct sg_mapping_iter m;
 506         unsigned int len;
 507         unsigned int block_size = dev->dev_attrib.block_size;
 508         unsigned int compare_len = (cmd->t_task_nolb * block_size);
 509         unsigned int miscmp_off = 0;
 510         sense_reason_t ret = TCM_NO_SENSE;
 511         int i;
 512
 513         /*
 514          * Handle early failure in transport_generic_request_failure(),
 515          * which will not have taken ->caw_sem yet..
 516          */
 517         if (!success && (!cmd->t_data_sg || !cmd->t_bidi_data_sg))
 518                 return TCM_NO_SENSE;
 519         /*
 520          * Handle special case for zero-length COMPARE_AND_WRITE
 521          */
 522         if (!cmd->data_length)
 523                 goto out;
 524         /*
 525          * Immediately exit + release dev->caw_sem if command has already
 526          * been failed with a non-zero SCSI status.
 527          */
 528         if (cmd->scsi_status) {
 529                 pr_debug("compare_and_write_callback: non zero scsi_status:"
 530                         " 0x%02x\n", cmd->scsi_status);
 531                 *post_ret = 1;
 532                 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION)
 533                         ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 534                 goto out;
 535         }
 536
 537         ret = compare_and_write_do_cmp(cmd->t_bidi_data_sg,
 538                                        cmd->t_bidi_data_nents,
 539                                        cmd->t_data_sg,
 540                                        cmd->t_data_nents,
 541                                        compare_len,
 542                                        &miscmp_off);
 543         if (ret == TCM_MISCOMPARE_VERIFY) {
 544                 /*
 545                  * SBC-4 r15: 5.3 COMPARE AND WRITE command
 546                  * In the sense data (see 4.18 and SPC-5) the offset from the
 547                  * start of the Data-Out Buffer to the first byte of data that
 548                  * was not equal shall be reported in the INFORMATION field.
 549                  */
 550                 cmd->sense_info = miscmp_off;
 551                 goto out;
 552         } else if (ret)
 553                 goto out;
 554
 555         if (sg_alloc_table(&write_tbl, cmd->t_data_nents, GFP_KERNEL) < 0) {
 556                 pr_err("Unable to allocate compare_and_write sg\n");
 557                 ret = TCM_OUT_OF_RESOURCES;
 558                 goto out;
 559         }
 560         write_sg = write_tbl.sgl;
 561
 562         i = 0;
 563         len = compare_len;
 564         sg_miter_start(&m, cmd->t_data_sg, cmd->t_data_nents, SG_MITER_TO_SG);
 565         /*
 566          * Currently assumes NoLB=1 and SGLs are PAGE_SIZE..
 567          */
 568         while (len) {
 569                 sg_miter_next(&m);
 570
 571                 if (block_size < PAGE_SIZE) {
 572                         sg_set_page(&write_sg[i], m.page, block_size,
 573                                     m.piter.sg->offset + block_size);
 574                 } else {
 575                         sg_miter_next(&m);
 576                         sg_set_page(&write_sg[i], m.page, block_size,
 577                                     m.piter.sg->offset);
 578                 }
 579                 len -= block_size;
 580                 i++;
 581         }
 582         sg_miter_stop(&m);
 583         /*
 584          * Save the original SGL + nents values before updating to new
 585          * assignments, to be released in transport_free_pages() ->
 586          * transport_reset_sgl_orig()
 587          */
 588         cmd->t_data_sg_orig = cmd->t_data_sg;
 589         cmd->t_data_sg = write_sg;
 590         cmd->t_data_nents_orig = cmd->t_data_nents;
 591         cmd->t_data_nents = 1;
 592
 593         cmd->sam_task_attr = TCM_HEAD_TAG;
 594         cmd->transport_complete_callback = compare_and_write_post;
 595         /*
 596          * Now reset ->execute_cmd() to the normal sbc_execute_rw() handler
 597          * for submitting the adjusted SGL to write instance user-data.
 598          */
 599         cmd->execute_cmd = sbc_execute_rw;
 600
 601         spin_lock_irq(&cmd->t_state_lock);
 602         cmd->t_state = TRANSPORT_PROCESSING;
 603         cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT;
 604         spin_unlock_irq(&cmd->t_state_lock);
 605
 606         __target_execute_cmd(cmd, false);
 607
 608         return ret;
 609
 610 out:
 611         /*
 612          * In the MISCOMPARE or failure case, unlock ->caw_sem obtained in
 613          * sbc_compare_and_write() before the original READ I/O submission.
 614          */
 615         up(&dev->caw_sem);
 616         sg_free_table(&write_tbl);
 617         return ret;
 618 }
 619
 620 static sense_reason_t
 621 sbc_compare_and_write(struct se_cmd *cmd)
 622 {
 623         struct sbc_ops *ops = cmd->protocol_data;
 624         struct se_device *dev = cmd->se_dev;
 625         sense_reason_t ret;
 626         int rc;
 627         /*
 628          * Submit the READ first for COMPARE_AND_WRITE to perform the
 629          * comparision using SGLs at cmd->t_bidi_data_sg..
 630          */
 631         rc = down_interruptible(&dev->caw_sem);
 632         if (rc != 0) {
 633                 cmd->transport_complete_callback = NULL;
 634                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 635         }
 636         /*
 637          * Reset cmd->data_length to individual block_size in order to not
 638          * confuse backend drivers that depend on this value matching the
 639          * size of the I/O being submitted.
 640          */
 641         cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size;
 642
 643         ret = ops->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents,
 644                               DMA_FROM_DEVICE);
 645         if (ret) {
 646                 cmd->transport_complete_callback = NULL;
 647                 up(&dev->caw_sem);
 648                 return ret;
 649         }
 650         /*
 651          * Unlock of dev->caw_sem to occur in compare_and_write_callback()
 652          * upon MISCOMPARE, or in compare_and_write_done() upon completion
 653          * of WRITE instance user-data.
 654          */
 655         return TCM_NO_SENSE;
 656 }
 657
 658 static int
 659 sbc_set_prot_op_checks(u8 protect, bool fabric_prot, enum target_prot_type prot_type,
 660                        bool is_write, struct se_cmd *cmd)
 661 {
 662         if (is_write) {
 663                 cmd->prot_op = fabric_prot ? TARGET_PROT_DOUT_STRIP :
 664                                protect ? TARGET_PROT_DOUT_PASS :
 665                                TARGET_PROT_DOUT_INSERT;
 666                 switch (protect) {
 667                 case 0x0:
 668                 case 0x3:
 669                         cmd->prot_checks = 0;
 670                         break;
 671                 case 0x1:
 672                 case 0x5:
 673                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 674                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 675                                 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 676                         break;
 677                 case 0x2:
 678                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 679                                 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 680                         break;
 681                 case 0x4:
 682                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 683                         break;
 684                 default:
 685                         pr_err("Unsupported protect field %d\n", protect);
 686                         return -EINVAL;
 687                 }
 688         } else {
 689                 cmd->prot_op = fabric_prot ? TARGET_PROT_DIN_INSERT :
 690                                protect ? TARGET_PROT_DIN_PASS :
 691                                TARGET_PROT_DIN_STRIP;
 692                 switch (protect) {
 693                 case 0x0:
 694                 case 0x1:
 695                 case 0x5:
 696                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 697                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 698                                 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 699                         break;
 700                 case 0x2:
 701                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 702                                 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 703                         break;
 704                 case 0x3:
 705                         cmd->prot_checks = 0;
 706                         break;
 707                 case 0x4:
 708                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 709                         break;
 710                 default:
 711                         pr_err("Unsupported protect field %d\n", protect);
 712                         return -EINVAL;
 713                 }
 714         }
 715
 716         return 0;
 717 }
 718
 719 static sense_reason_t
 720 sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb,
 721                u32 sectors, bool is_write)
 722 {
 723         u8 protect = cdb[1] >> 5;
 724         int sp_ops = cmd->se_sess->sup_prot_ops;
 725         int pi_prot_type = dev->dev_attrib.pi_prot_type;
 726         bool fabric_prot = false;
 727
 728         if (!cmd->t_prot_sg || !cmd->t_prot_nents) {
 729                 if (unlikely(protect &&
 730                     !dev->dev_attrib.pi_prot_type && !cmd->se_sess->sess_prot_type)) {
 731                         pr_err("CDB contains protect bit, but device + fabric does"
 732                                " not advertise PROTECT=1 feature bit\n");
 733                         return TCM_INVALID_CDB_FIELD;
 734                 }
 735                 if (cmd->prot_pto)
 736                         return TCM_NO_SENSE;
 737         }
 738
 739         switch (dev->dev_attrib.pi_prot_type) {
 740         case TARGET_DIF_TYPE3_PROT:
 741                 cmd->reftag_seed = 0xffffffff;
 742                 break;
 743         case TARGET_DIF_TYPE2_PROT:
 744                 if (protect)
 745                         return TCM_INVALID_CDB_FIELD;
 746
 747                 cmd->reftag_seed = cmd->t_task_lba;
 748                 break;
 749         case TARGET_DIF_TYPE1_PROT:
 750                 cmd->reftag_seed = cmd->t_task_lba;
 751                 break;
 752         case TARGET_DIF_TYPE0_PROT:
 753                 /*
 754                  * See if the fabric supports T10-PI, and the session has been
 755                  * configured to allow export PROTECT=1 feature bit with backend
 756                  * devices that don't support T10-PI.
 757                  */
 758                 fabric_prot = is_write ?
 759                               !!(sp_ops & (TARGET_PROT_DOUT_PASS | TARGET_PROT_DOUT_STRIP)) :
 760                               !!(sp_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DIN_INSERT));
 761
 762                 if (fabric_prot && cmd->se_sess->sess_prot_type) {
 763                         pi_prot_type = cmd->se_sess->sess_prot_type;
 764                         break;
 765                 }
 766                 if (!protect)
 767                         return TCM_NO_SENSE;
 768                 fallthrough;
 769         default:
 770                 pr_err("Unable to determine pi_prot_type for CDB: 0x%02x "
 771                        "PROTECT: 0x%02x\n", cdb[0], protect);
 772                 return TCM_INVALID_CDB_FIELD;
 773         }
 774
 775         if (sbc_set_prot_op_checks(protect, fabric_prot, pi_prot_type, is_write, cmd))
 776                 return TCM_INVALID_CDB_FIELD;
 777
 778         cmd->prot_type = pi_prot_type;
 779         cmd->prot_length = dev->prot_length * sectors;
 780
 781         /**
 782          * In case protection information exists over the wire
 783          * we modify command data length to describe pure data.
 784          * The actual transfer length is data length + protection
 785          * length
 786          **/
 787         if (protect)
 788                 cmd->data_length = sectors * dev->dev_attrib.block_size;
 789
 790         pr_debug("%s: prot_type=%d, data_length=%d, prot_length=%d "
 791                  "prot_op=%d prot_checks=%d\n",
 792                  __func__, cmd->prot_type, cmd->data_length, cmd->prot_length,
 793                  cmd->prot_op, cmd->prot_checks);
 794
 795         return TCM_NO_SENSE;
 796 }
 797
 798 static int
 799 sbc_check_dpofua(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb)
 800 {
 801         if (cdb[1] & 0x10) {
 802                 /* see explanation in spc_emulate_modesense */
 803                 if (!target_check_fua(dev)) {
 804                         pr_err("Got CDB: 0x%02x with DPO bit set, but device"
 805                                " does not advertise support for DPO\n", cdb[0]);
 806                         return -EINVAL;
 807                 }
 808         }
 809         if (cdb[1] & 0x8) {
 810                 if (!target_check_fua(dev)) {
 811                         pr_err("Got CDB: 0x%02x with FUA bit set, but device"
 812                                " does not advertise support for FUA write\n",
 813                                cdb[0]);
 814                         return -EINVAL;
 815                 }
 816                 cmd->se_cmd_flags |= SCF_FUA;
 817         }
 818         return 0;
 819 }
 820
 821 sense_reason_t
 822 sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 823 {
 824         struct se_device *dev = cmd->se_dev;
 825         unsigned char *cdb = cmd->t_task_cdb;
 826         unsigned int size;
 827         u32 sectors = 0;
 828         sense_reason_t ret;
 829
 830         cmd->protocol_data = ops;
 831
 832         switch (cdb[0]) {
 833         case READ_6:
 834                 sectors = transport_get_sectors_6(cdb);
 835                 cmd->t_task_lba = transport_lba_21(cdb);
 836                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 837                 cmd->execute_cmd = sbc_execute_rw;
 838                 break;
 839         case READ_10:
 840                 sectors = transport_get_sectors_10(cdb);
 841                 cmd->t_task_lba = transport_lba_32(cdb);
 842
 843                 if (sbc_check_dpofua(dev, cmd, cdb))
 844                         return TCM_INVALID_CDB_FIELD;
 845
 846                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 847                 if (ret)
 848                         return ret;
 849
 850                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 851                 cmd->execute_cmd = sbc_execute_rw;
 852                 break;
 853         case READ_12:
 854                 sectors = transport_get_sectors_12(cdb);
 855                 cmd->t_task_lba = transport_lba_32(cdb);
 856
 857                 if (sbc_check_dpofua(dev, cmd, cdb))
 858                         return TCM_INVALID_CDB_FIELD;
 859
 860                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 861                 if (ret)
 862                         return ret;
 863
 864                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 865                 cmd->execute_cmd = sbc_execute_rw;
 866                 break;
 867         case READ_16:
 868                 sectors = transport_get_sectors_16(cdb);
 869                 cmd->t_task_lba = transport_lba_64(cdb);
 870
 871                 if (sbc_check_dpofua(dev, cmd, cdb))
 872                         return TCM_INVALID_CDB_FIELD;
 873
 874                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 875                 if (ret)
 876                         return ret;
 877
 878                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 879                 cmd->execute_cmd = sbc_execute_rw;
 880                 break;
 881         case WRITE_6:
 882                 sectors = transport_get_sectors_6(cdb);
 883                 cmd->t_task_lba = transport_lba_21(cdb);
 884                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 885                 cmd->execute_cmd = sbc_execute_rw;
 886                 break;
 887         case WRITE_10:
 888         case WRITE_VERIFY:
 889                 sectors = transport_get_sectors_10(cdb);
 890                 cmd->t_task_lba = transport_lba_32(cdb);
 891
 892                 if (sbc_check_dpofua(dev, cmd, cdb))
 893                         return TCM_INVALID_CDB_FIELD;
 894
 895                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 896                 if (ret)
 897                         return ret;
 898
 899                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 900                 cmd->execute_cmd = sbc_execute_rw;
 901                 break;
 902         case WRITE_12:
 903                 sectors = transport_get_sectors_12(cdb);
 904                 cmd->t_task_lba = transport_lba_32(cdb);
 905
 906                 if (sbc_check_dpofua(dev, cmd, cdb))
 907                         return TCM_INVALID_CDB_FIELD;
 908
 909                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 910                 if (ret)
 911                         return ret;
 912
 913                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 914                 cmd->execute_cmd = sbc_execute_rw;
 915                 break;
 916         case WRITE_16:
 917         case WRITE_VERIFY_16:
 918                 sectors = transport_get_sectors_16(cdb);
 919                 cmd->t_task_lba = transport_lba_64(cdb);
 920
 921                 if (sbc_check_dpofua(dev, cmd, cdb))
 922                         return TCM_INVALID_CDB_FIELD;
 923
 924                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 925                 if (ret)
 926                         return ret;
 927
 928                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 929                 cmd->execute_cmd = sbc_execute_rw;
 930                 break;
 931         case XDWRITEREAD_10:
 932                 if (cmd->data_direction != DMA_TO_DEVICE ||
 933                     !(cmd->se_cmd_flags & SCF_BIDI))
 934                         return TCM_INVALID_CDB_FIELD;
 935                 sectors = transport_get_sectors_10(cdb);
 936
 937                 if (sbc_check_dpofua(dev, cmd, cdb))
 938                         return TCM_INVALID_CDB_FIELD;
 939
 940                 cmd->t_task_lba = transport_lba_32(cdb);
 941                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 942
 943                 /*
 944                  * Setup BIDI XOR callback to be run after I/O completion.
 945                  */
 946                 cmd->execute_cmd = sbc_execute_rw;
 947                 cmd->transport_complete_callback = &xdreadwrite_callback;
 948                 break;
 949         case VARIABLE_LENGTH_CMD:
 950         {
 951                 u16 service_action = get_unaligned_be16(&cdb[8]);
 952                 switch (service_action) {
 953                 case XDWRITEREAD_32:
 954                         sectors = transport_get_sectors_32(cdb);
 955
 956                         if (sbc_check_dpofua(dev, cmd, cdb))
 957                                 return TCM_INVALID_CDB_FIELD;
 958                         /*
 959                          * Use WRITE_32 and READ_32 opcodes for the emulated
 960                          * XDWRITE_READ_32 logic.
 961                          */
 962                         cmd->t_task_lba = transport_lba_64_ext(cdb);
 963                         cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 964
 965                         /*
 966                          * Setup BIDI XOR callback to be run during after I/O
 967                          * completion.
 968                          */
 969                         cmd->execute_cmd = sbc_execute_rw;
 970                         cmd->transport_complete_callback = &xdreadwrite_callback;
 971                         break;
 972                 case WRITE_SAME_32:
 973                         sectors = transport_get_sectors_32(cdb);
 974                         if (!sectors) {
 975                                 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
 976                                        " supported\n");
 977                                 return TCM_INVALID_CDB_FIELD;
 978                         }
 979
 980                         size = sbc_get_size(cmd, 1);
 981                         cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
 982
 983                         ret = sbc_setup_write_same(cmd, &cdb[10], ops);
 984                         if (ret)
 985                                 return ret;
 986                         break;
 987                 default:
 988                         pr_err("VARIABLE_LENGTH_CMD service action"
 989                                 " 0x%04x not supported\n", service_action);
 990                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 991                 }
 992                 break;
 993         }
 994         case COMPARE_AND_WRITE:
 995                 if (!dev->dev_attrib.emulate_caw) {
 996                         pr_err_ratelimited("se_device %s/%s (vpd_unit_serial %s) reject COMPARE_AND_WRITE\n",
 997                                            dev->se_hba->backend->ops->name,
 998                                            config_item_name(&dev->dev_group.cg_item),
 999                                            dev->t10_wwn.unit_serial);
1000                         return TCM_UNSUPPORTED_SCSI_OPCODE;
1001                 }
1002                 sectors = cdb[13];
1003                 /*
1004                  * Currently enforce COMPARE_AND_WRITE for a single sector
1005                  */
1006                 if (sectors > 1) {
1007                         pr_err("COMPARE_AND_WRITE contains NoLB: %u greater"
1008                                " than 1\n", sectors);
1009                         return TCM_INVALID_CDB_FIELD;
1010                 }
1011                 if (sbc_check_dpofua(dev, cmd, cdb))
1012                         return TCM_INVALID_CDB_FIELD;
1013
1014                 /*
1015                  * Double size because we have two buffers, note that
1016                  * zero is not an error..
1017                  */
1018                 size = 2 * sbc_get_size(cmd, sectors);
1019                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1020                 cmd->t_task_nolb = sectors;
1021                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE;
1022                 cmd->execute_cmd = sbc_compare_and_write;
1023                 cmd->transport_complete_callback = compare_and_write_callback;
1024                 break;
1025         case READ_CAPACITY:
1026                 size = READ_CAP_LEN;
1027                 cmd->execute_cmd = sbc_emulate_readcapacity;
1028                 break;
1029         case SERVICE_ACTION_IN_16:
1030                 switch (cmd->t_task_cdb[1] & 0x1f) {
1031                 case SAI_READ_CAPACITY_16:
1032                         cmd->execute_cmd = sbc_emulate_readcapacity_16;
1033                         break;
1034                 case SAI_REPORT_REFERRALS:
1035                         cmd->execute_cmd = target_emulate_report_referrals;
1036                         break;
1037                 default:
1038                         pr_err("Unsupported SA: 0x%02x\n",
1039                                 cmd->t_task_cdb[1] & 0x1f);
1040                         return TCM_INVALID_CDB_FIELD;
1041                 }
1042                 size = get_unaligned_be32(&cdb[10]);
1043                 break;
1044         case SYNCHRONIZE_CACHE:
1045         case SYNCHRONIZE_CACHE_16:
1046                 if (cdb[0] == SYNCHRONIZE_CACHE) {
1047                         sectors = transport_get_sectors_10(cdb);
1048                         cmd->t_task_lba = transport_lba_32(cdb);
1049                 } else {
1050                         sectors = transport_get_sectors_16(cdb);
1051                         cmd->t_task_lba = transport_lba_64(cdb);
1052                 }
1053                 if (ops->execute_sync_cache) {
1054                         cmd->execute_cmd = ops->execute_sync_cache;
1055                         goto check_lba;
1056                 }
1057                 size = 0;
1058                 cmd->execute_cmd = sbc_emulate_noop;
1059                 break;
1060         case UNMAP:
1061                 if (!ops->execute_unmap)
1062                         return TCM_UNSUPPORTED_SCSI_OPCODE;
1063
1064                 if (!dev->dev_attrib.emulate_tpu) {
1065                         pr_err("Got UNMAP, but backend device has"
1066                                " emulate_tpu disabled\n");
1067                         return TCM_UNSUPPORTED_SCSI_OPCODE;
1068                 }
1069                 size = get_unaligned_be16(&cdb[7]);
1070                 cmd->execute_cmd = sbc_execute_unmap;
1071                 break;
1072         case WRITE_SAME_16:
1073                 sectors = transport_get_sectors_16(cdb);
1074                 if (!sectors) {
1075                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1076                         return TCM_INVALID_CDB_FIELD;
1077                 }
1078
1079                 size = sbc_get_size(cmd, 1);
1080                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1081
1082                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1083                 if (ret)
1084                         return ret;
1085                 break;
1086         case WRITE_SAME:
1087                 sectors = transport_get_sectors_10(cdb);
1088                 if (!sectors) {
1089                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1090                         return TCM_INVALID_CDB_FIELD;
1091                 }
1092
1093                 size = sbc_get_size(cmd, 1);
1094                 cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
1095
1096                 /*
1097                  * Follow sbcr26 with WRITE_SAME (10) and check for the existence
1098                  * of byte 1 bit 3 UNMAP instead of original reserved field
1099                  */
1100                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1101                 if (ret)
1102                         return ret;
1103                 break;
1104         case VERIFY:
1105         case VERIFY_16:
1106                 size = 0;
1107                 if (cdb[0] == VERIFY) {
1108                         sectors = transport_get_sectors_10(cdb);
1109                         cmd->t_task_lba = transport_lba_32(cdb);
1110                 } else {
1111                         sectors = transport_get_sectors_16(cdb);
1112                         cmd->t_task_lba = transport_lba_64(cdb);
1113                 }
1114                 cmd->execute_cmd = sbc_emulate_noop;
1115                 goto check_lba;
1116         case REZERO_UNIT:
1117         case SEEK_6:
1118         case SEEK_10:
1119                 /*
1120                  * There are still clients out there which use these old SCSI-2
1121                  * commands. This mainly happens when running VMs with legacy
1122                  * guest systems, connected via SCSI command pass-through to
1123                  * iSCSI targets. Make them happy and return status GOOD.
1124                  */
1125                 size = 0;
1126                 cmd->execute_cmd = sbc_emulate_noop;
1127                 break;
1128         case START_STOP:
1129                 size = 0;
1130                 cmd->execute_cmd = sbc_emulate_startstop;
1131                 break;
1132         default:
1133                 ret = spc_parse_cdb(cmd, &size);
1134                 if (ret)
1135                         return ret;
1136         }
1137
1138         /* reject any command that we don't have a handler for */
1139         if (!cmd->execute_cmd)
1140                 return TCM_UNSUPPORTED_SCSI_OPCODE;
1141
1142         if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1143                 unsigned long long end_lba;
1144 check_lba:
1145                 end_lba = dev->transport->get_blocks(dev) + 1;
1146                 if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
1147                     ((cmd->t_task_lba + sectors) > end_lba)) {
1148                         pr_err("cmd exceeds last lba %llu "
1149                                 "(lba %llu, sectors %u)\n",
1150                                 end_lba, cmd->t_task_lba, sectors);
1151                         return TCM_ADDRESS_OUT_OF_RANGE;
1152                 }
1153
1154                 if (!(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE))
1155                         size = sbc_get_size(cmd, sectors);
1156         }
1157
1158         return target_cmd_size_check(cmd, size);
1159 }
1160 EXPORT_SYMBOL(sbc_parse_cdb);
1161
1162 u32 sbc_get_device_type(struct se_device *dev)
1163 {
1164         return TYPE_DISK;
1165 }
1166 EXPORT_SYMBOL(sbc_get_device_type);
1167
1168 static sense_reason_t
1169 sbc_execute_unmap(struct se_cmd *cmd)
1170 {
1171         struct sbc_ops *ops = cmd->protocol_data;
1172         struct se_device *dev = cmd->se_dev;
1173         unsigned char *buf, *ptr = NULL;
1174         sector_t lba;
1175         int size;
1176         u32 range;
1177         sense_reason_t ret = 0;
1178         int dl, bd_dl;
1179
1180         /* We never set ANC_SUP */
1181         if (cmd->t_task_cdb[1])
1182                 return TCM_INVALID_CDB_FIELD;
1183
1184         if (cmd->data_length == 0) {
1185                 target_complete_cmd(cmd, SAM_STAT_GOOD);
1186                 return 0;
1187         }
1188
1189         if (cmd->data_length < 8) {
1190                 pr_warn("UNMAP parameter list length %u too small\n",
1191                         cmd->data_length);
1192                 return TCM_PARAMETER_LIST_LENGTH_ERROR;
1193         }
1194
1195         buf = transport_kmap_data_sg(cmd);
1196         if (!buf)
1197                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1198
1199         dl = get_unaligned_be16(&buf[0]);
1200         bd_dl = get_unaligned_be16(&buf[2]);
1201
1202         size = cmd->data_length - 8;
1203         if (bd_dl > size)
1204                 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
1205                         cmd->data_length, bd_dl);
1206         else
1207                 size = bd_dl;
1208
1209         if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
1210                 ret = TCM_INVALID_PARAMETER_LIST;
1211                 goto err;
1212         }
1213
1214         /* First UNMAP block descriptor starts at 8 byte offset */
1215         ptr = &buf[8];
1216         pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
1217                 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
1218
1219         while (size >= 16) {
1220                 lba = get_unaligned_be64(&ptr[0]);
1221                 range = get_unaligned_be32(&ptr[8]);
1222                 pr_debug("UNMAP: Using lba: %llu and range: %u\n",
1223                                  (unsigned long long)lba, range);
1224
1225                 if (range > dev->dev_attrib.max_unmap_lba_count) {
1226                         ret = TCM_INVALID_PARAMETER_LIST;
1227                         goto err;
1228                 }
1229
1230                 if (lba + range > dev->transport->get_blocks(dev) + 1) {
1231                         ret = TCM_ADDRESS_OUT_OF_RANGE;
1232                         goto err;
1233                 }
1234
1235                 if (range) {
1236                         ret = ops->execute_unmap(cmd, lba, range);
1237                         if (ret)
1238                                 goto err;
1239                 }
1240
1241                 ptr += 16;
1242                 size -= 16;
1243         }
1244
1245 err:
1246         transport_kunmap_data_sg(cmd);
1247         if (!ret)
1248                 target_complete_cmd(cmd, GOOD);
1249         return ret;
1250 }
1251
1252 void
1253 sbc_dif_generate(struct se_cmd *cmd)
1254 {
1255         struct se_device *dev = cmd->se_dev;
1256         struct t10_pi_tuple *sdt;
1257         struct scatterlist *dsg = cmd->t_data_sg, *psg;
1258         sector_t sector = cmd->t_task_lba;
1259         void *daddr, *paddr;
1260         int i, j, offset = 0;
1261         unsigned int block_size = dev->dev_attrib.block_size;
1262
1263         for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1264                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1265                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1266
1267                 for (j = 0; j < psg->length;
1268                                 j += sizeof(*sdt)) {
1269                         __u16 crc;
1270                         unsigned int avail;
1271
1272                         if (offset >= dsg->length) {
1273                                 offset -= dsg->length;
1274                                 kunmap_atomic(daddr - dsg->offset);
1275                                 dsg = sg_next(dsg);
1276                                 if (!dsg) {
1277                                         kunmap_atomic(paddr - psg->offset);
1278                                         return;
1279                                 }
1280                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1281                         }
1282
1283                         sdt = paddr + j;
1284                         avail = min(block_size, dsg->length - offset);
1285                         crc = crc_t10dif(daddr + offset, avail);
1286                         if (avail < block_size) {
1287                                 kunmap_atomic(daddr - dsg->offset);
1288                                 dsg = sg_next(dsg);
1289                                 if (!dsg) {
1290                                         kunmap_atomic(paddr - psg->offset);
1291                                         return;
1292                                 }
1293                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1294                                 offset = block_size - avail;
1295                                 crc = crc_t10dif_update(crc, daddr, offset);
1296                         } else {
1297                                 offset += block_size;
1298                         }
1299
1300                         sdt->guard_tag = cpu_to_be16(crc);
1301                         if (cmd->prot_type == TARGET_DIF_TYPE1_PROT)
1302                                 sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
1303                         sdt->app_tag = 0;
1304
1305                         pr_debug("DIF %s INSERT sector: %llu guard_tag: 0x%04x"
1306                                  " app_tag: 0x%04x ref_tag: %u\n",
1307                                  (cmd->data_direction == DMA_TO_DEVICE) ?
1308                                  "WRITE" : "READ", (unsigned long long)sector,
1309                                  sdt->guard_tag, sdt->app_tag,
1310                                  be32_to_cpu(sdt->ref_tag));
1311
1312                         sector++;
1313                 }
1314
1315                 kunmap_atomic(daddr - dsg->offset);
1316                 kunmap_atomic(paddr - psg->offset);
1317         }
1318 }
1319
1320 static sense_reason_t
1321 sbc_dif_v1_verify(struct se_cmd *cmd, struct t10_pi_tuple *sdt,
1322                   __u16 crc, sector_t sector, unsigned int ei_lba)
1323 {
1324         __be16 csum;
1325
1326         if (!(cmd->prot_checks & TARGET_DIF_CHECK_GUARD))
1327                 goto check_ref;
1328
1329         csum = cpu_to_be16(crc);
1330
1331         if (sdt->guard_tag != csum) {
1332                 pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x"
1333                         " csum 0x%04x\n", (unsigned long long)sector,
1334                         be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
1335                 return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
1336         }
1337
1338 check_ref:
1339         if (!(cmd->prot_checks & TARGET_DIF_CHECK_REFTAG))
1340                 return 0;
1341
1342         if (cmd->prot_type == TARGET_DIF_TYPE1_PROT &&
1343             be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
1344                 pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x"
1345                        " sector MSB: 0x%08x\n", (unsigned long long)sector,
1346                        be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff));
1347                 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1348         }
1349
1350         if (cmd->prot_type == TARGET_DIF_TYPE2_PROT &&
1351             be32_to_cpu(sdt->ref_tag) != ei_lba) {
1352                 pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x"
1353                        " ei_lba: 0x%08x\n", (unsigned long long)sector,
1354                         be32_to_cpu(sdt->ref_tag), ei_lba);
1355                 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1356         }
1357
1358         return 0;
1359 }
1360
1361 void sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read,
1362                        struct scatterlist *sg, int sg_off)
1363 {
1364         struct se_device *dev = cmd->se_dev;
1365         struct scatterlist *psg;
1366         void *paddr, *addr;
1367         unsigned int i, len, left;
1368         unsigned int offset = sg_off;
1369
1370         if (!sg)
1371                 return;
1372
1373         left = sectors * dev->prot_length;
1374
1375         for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1376                 unsigned int psg_len, copied = 0;
1377
1378                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1379                 psg_len = min(left, psg->length);
1380                 while (psg_len) {
1381                         len = min(psg_len, sg->length - offset);
1382                         addr = kmap_atomic(sg_page(sg)) + sg->offset + offset;
1383
1384                         if (read)
1385                                 memcpy(paddr + copied, addr, len);
1386                         else
1387                                 memcpy(addr, paddr + copied, len);
1388
1389                         left -= len;
1390                         offset += len;
1391                         copied += len;
1392                         psg_len -= len;
1393
1394                         kunmap_atomic(addr - sg->offset - offset);
1395
1396                         if (offset >= sg->length) {
1397                                 sg = sg_next(sg);
1398                                 offset = 0;
1399                         }
1400                 }
1401                 kunmap_atomic(paddr - psg->offset);
1402         }
1403 }
1404 EXPORT_SYMBOL(sbc_dif_copy_prot);
1405
1406 sense_reason_t
1407 sbc_dif_verify(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1408                unsigned int ei_lba, struct scatterlist *psg, int psg_off)
1409 {
1410         struct se_device *dev = cmd->se_dev;
1411         struct t10_pi_tuple *sdt;
1412         struct scatterlist *dsg = cmd->t_data_sg;
1413         sector_t sector = start;
1414         void *daddr, *paddr;
1415         int i;
1416         sense_reason_t rc;
1417         int dsg_off = 0;
1418         unsigned int block_size = dev->dev_attrib.block_size;
1419
1420         for (; psg && sector < start + sectors; psg = sg_next(psg)) {
1421                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1422                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1423
1424                 for (i = psg_off; i < psg->length &&
1425                                 sector < start + sectors;
1426                                 i += sizeof(*sdt)) {
1427                         __u16 crc;
1428                         unsigned int avail;
1429
1430                         if (dsg_off >= dsg->length) {
1431                                 dsg_off -= dsg->length;
1432                                 kunmap_atomic(daddr - dsg->offset);
1433                                 dsg = sg_next(dsg);
1434                                 if (!dsg) {
1435                                         kunmap_atomic(paddr - psg->offset);
1436                                         return 0;
1437                                 }
1438                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1439                         }
1440
1441                         sdt = paddr + i;
1442
1443                         pr_debug("DIF READ sector: %llu guard_tag: 0x%04x"
1444                                  " app_tag: 0x%04x ref_tag: %u\n",
1445                                  (unsigned long long)sector, sdt->guard_tag,
1446                                  sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1447
1448                         if (sdt->app_tag == T10_PI_APP_ESCAPE) {
1449                                 dsg_off += block_size;
1450                                 goto next;
1451                         }
1452
1453                         avail = min(block_size, dsg->length - dsg_off);
1454                         crc = crc_t10dif(daddr + dsg_off, avail);
1455                         if (avail < block_size) {
1456                                 kunmap_atomic(daddr - dsg->offset);
1457                                 dsg = sg_next(dsg);
1458                                 if (!dsg) {
1459                                         kunmap_atomic(paddr - psg->offset);
1460                                         return 0;
1461                                 }
1462                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1463                                 dsg_off = block_size - avail;
1464                                 crc = crc_t10dif_update(crc, daddr, dsg_off);
1465                         } else {
1466                                 dsg_off += block_size;
1467                         }
1468
1469                         rc = sbc_dif_v1_verify(cmd, sdt, crc, sector, ei_lba);
1470                         if (rc) {
1471                                 kunmap_atomic(daddr - dsg->offset);
1472                                 kunmap_atomic(paddr - psg->offset);
1473                                 cmd->sense_info = sector;
1474                                 return rc;
1475                         }
1476 next:
1477                         sector++;
1478                         ei_lba++;
1479                 }
1480
1481                 psg_off = 0;
1482                 kunmap_atomic(daddr - dsg->offset);
1483                 kunmap_atomic(paddr - psg->offset);
1484         }
1485
1486         return 0;
1487 }
1488 EXPORT_SYMBOL(sbc_dif_verify);