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          * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
 365          *
 366          * 1) read the specified logical block(s);
 367          * 2) transfer logical blocks from the data-out buffer;
 368          * 3) XOR the logical blocks transferred from the data-out buffer with
 369          *    the logical blocks read, storing the resulting XOR data in a buffer;
 370          * 4) if the DISABLE WRITE bit is set to zero, then write the logical
 371          *    blocks transferred from the data-out buffer; and
 372          * 5) transfer the resulting XOR data to the data-in buffer.
 373          */
 374         buf = kmalloc(cmd->data_length, GFP_KERNEL);
 375         if (!buf) {
 376                 pr_err("Unable to allocate xor_callback buf\n");
 377                 return TCM_OUT_OF_RESOURCES;
 378         }
 379         /*
 380          * Copy the scatterlist WRITE buffer located at cmd->t_data_sg
 381          * into the locally allocated *buf
 382          */
 383         sg_copy_to_buffer(cmd->t_data_sg,
 384                           cmd->t_data_nents,
 385                           buf,
 386                           cmd->data_length);
 387
 388         /*
 389          * Now perform the XOR against the BIDI read memory located at
 390          * cmd->t_mem_bidi_list
 391          */
 392
 393         offset = 0;
 394         for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
 395                 addr = kmap_atomic(sg_page(sg));
 396                 if (!addr) {
 397                         ret = TCM_OUT_OF_RESOURCES;
 398                         goto out;
 399                 }
 400
 401                 for (i = 0; i < sg->length; i++)
 402                         *(addr + sg->offset + i) ^= *(buf + offset + i);
 403
 404                 offset += sg->length;
 405                 kunmap_atomic(addr);
 406         }
 407
 408 out:
 409         kfree(buf);
 410         return ret;
 411 }
 412
 413 static sense_reason_t
 414 sbc_execute_rw(struct se_cmd *cmd)
 415 {
 416         struct sbc_ops *ops = cmd->protocol_data;
 417
 418         return ops->execute_rw(cmd, cmd->t_data_sg, cmd->t_data_nents,
 419                                cmd->data_direction);
 420 }
 421
 422 static sense_reason_t compare_and_write_post(struct se_cmd *cmd, bool success,
 423                                              int *post_ret)
 424 {
 425         struct se_device *dev = cmd->se_dev;
 426         sense_reason_t ret = TCM_NO_SENSE;
 427
 428         /*
 429          * Only set SCF_COMPARE_AND_WRITE_POST to force a response fall-through
 430          * within target_complete_ok_work() if the command was successfully
 431          * sent to the backend driver.
 432          */
 433         spin_lock_irq(&cmd->t_state_lock);
 434         if (cmd->transport_state & CMD_T_SENT) {
 435                 cmd->se_cmd_flags |= SCF_COMPARE_AND_WRITE_POST;
 436                 *post_ret = 1;
 437
 438                 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION)
 439                         ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 440         }
 441         spin_unlock_irq(&cmd->t_state_lock);
 442
 443         /*
 444          * Unlock ->caw_sem originally obtained during sbc_compare_and_write()
 445          * before the original READ I/O submission.
 446          */
 447         up(&dev->caw_sem);
 448
 449         return ret;
 450 }
 451
 452 static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool success,
 453                                                  int *post_ret)
 454 {
 455         struct se_device *dev = cmd->se_dev;
 456         struct scatterlist *write_sg = NULL, *sg;
 457         unsigned char *buf = NULL, *addr;
 458         struct sg_mapping_iter m;
 459         unsigned int offset = 0, len;
 460         unsigned int nlbas = cmd->t_task_nolb;
 461         unsigned int block_size = dev->dev_attrib.block_size;
 462         unsigned int compare_len = (nlbas * block_size);
 463         sense_reason_t ret = TCM_NO_SENSE;
 464         int rc, i;
 465
 466         /*
 467          * Handle early failure in transport_generic_request_failure(),
 468          * which will not have taken ->caw_sem yet..
 469          */
 470         if (!success && (!cmd->t_data_sg || !cmd->t_bidi_data_sg))
 471                 return TCM_NO_SENSE;
 472         /*
 473          * Handle special case for zero-length COMPARE_AND_WRITE
 474          */
 475         if (!cmd->data_length)
 476                 goto out;
 477         /*
 478          * Immediately exit + release dev->caw_sem if command has already
 479          * been failed with a non-zero SCSI status.
 480          */
 481         if (cmd->scsi_status) {
 482                 pr_debug("compare_and_write_callback: non zero scsi_status:"
 483                         " 0x%02x\n", cmd->scsi_status);
 484                 *post_ret = 1;
 485                 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION)
 486                         ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 487                 goto out;
 488         }
 489
 490         buf = kzalloc(cmd->data_length, GFP_KERNEL);
 491         if (!buf) {
 492                 pr_err("Unable to allocate compare_and_write buf\n");
 493                 ret = TCM_OUT_OF_RESOURCES;
 494                 goto out;
 495         }
 496
 497         write_sg = kmalloc_array(cmd->t_data_nents, sizeof(*write_sg),
 498                                  GFP_KERNEL);
 499         if (!write_sg) {
 500                 pr_err("Unable to allocate compare_and_write sg\n");
 501                 ret = TCM_OUT_OF_RESOURCES;
 502                 goto out;
 503         }
 504         sg_init_table(write_sg, cmd->t_data_nents);
 505         /*
 506          * Setup verify and write data payloads from total NumberLBAs.
 507          */
 508         rc = sg_copy_to_buffer(cmd->t_data_sg, cmd->t_data_nents, buf,
 509                                cmd->data_length);
 510         if (!rc) {
 511                 pr_err("sg_copy_to_buffer() failed for compare_and_write\n");
 512                 ret = TCM_OUT_OF_RESOURCES;
 513                 goto out;
 514         }
 515         /*
 516          * Compare against SCSI READ payload against verify payload
 517          */
 518         for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, i) {
 519                 addr = (unsigned char *)kmap_atomic(sg_page(sg));
 520                 if (!addr) {
 521                         ret = TCM_OUT_OF_RESOURCES;
 522                         goto out;
 523                 }
 524
 525                 len = min(sg->length, compare_len);
 526
 527                 if (memcmp(addr, buf + offset, len)) {
 528                         pr_warn("Detected MISCOMPARE for addr: %p buf: %p\n",
 529                                 addr, buf + offset);
 530                         kunmap_atomic(addr);
 531                         goto miscompare;
 532                 }
 533                 kunmap_atomic(addr);
 534
 535                 offset += len;
 536                 compare_len -= len;
 537                 if (!compare_len)
 538                         break;
 539         }
 540
 541         i = 0;
 542         len = cmd->t_task_nolb * block_size;
 543         sg_miter_start(&m, cmd->t_data_sg, cmd->t_data_nents, SG_MITER_TO_SG);
 544         /*
 545          * Currently assumes NoLB=1 and SGLs are PAGE_SIZE..
 546          */
 547         while (len) {
 548                 sg_miter_next(&m);
 549
 550                 if (block_size < PAGE_SIZE) {
 551                         sg_set_page(&write_sg[i], m.page, block_size,
 552                                     m.piter.sg->offset + block_size);
 553                 } else {
 554                         sg_miter_next(&m);
 555                         sg_set_page(&write_sg[i], m.page, block_size,
 556                                     m.piter.sg->offset);
 557                 }
 558                 len -= block_size;
 559                 i++;
 560         }
 561         sg_miter_stop(&m);
 562         /*
 563          * Save the original SGL + nents values before updating to new
 564          * assignments, to be released in transport_free_pages() ->
 565          * transport_reset_sgl_orig()
 566          */
 567         cmd->t_data_sg_orig = cmd->t_data_sg;
 568         cmd->t_data_sg = write_sg;
 569         cmd->t_data_nents_orig = cmd->t_data_nents;
 570         cmd->t_data_nents = 1;
 571
 572         cmd->sam_task_attr = TCM_HEAD_TAG;
 573         cmd->transport_complete_callback = compare_and_write_post;
 574         /*
 575          * Now reset ->execute_cmd() to the normal sbc_execute_rw() handler
 576          * for submitting the adjusted SGL to write instance user-data.
 577          */
 578         cmd->execute_cmd = sbc_execute_rw;
 579
 580         spin_lock_irq(&cmd->t_state_lock);
 581         cmd->t_state = TRANSPORT_PROCESSING;
 582         cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT;
 583         spin_unlock_irq(&cmd->t_state_lock);
 584
 585         __target_execute_cmd(cmd, false);
 586
 587         kfree(buf);
 588         return ret;
 589
 590 miscompare:
 591         pr_warn("Target/%s: Send MISCOMPARE check condition and sense\n",
 592                 dev->transport->name);
 593         ret = TCM_MISCOMPARE_VERIFY;
 594 out:
 595         /*
 596          * In the MISCOMPARE or failure case, unlock ->caw_sem obtained in
 597          * sbc_compare_and_write() before the original READ I/O submission.
 598          */
 599         up(&dev->caw_sem);
 600         kfree(write_sg);
 601         kfree(buf);
 602         return ret;
 603 }
 604
 605 static sense_reason_t
 606 sbc_compare_and_write(struct se_cmd *cmd)
 607 {
 608         struct sbc_ops *ops = cmd->protocol_data;
 609         struct se_device *dev = cmd->se_dev;
 610         sense_reason_t ret;
 611         int rc;
 612         /*
 613          * Submit the READ first for COMPARE_AND_WRITE to perform the
 614          * comparision using SGLs at cmd->t_bidi_data_sg..
 615          */
 616         rc = down_interruptible(&dev->caw_sem);
 617         if (rc != 0) {
 618                 cmd->transport_complete_callback = NULL;
 619                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 620         }
 621         /*
 622          * Reset cmd->data_length to individual block_size in order to not
 623          * confuse backend drivers that depend on this value matching the
 624          * size of the I/O being submitted.
 625          */
 626         cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size;
 627
 628         ret = ops->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents,
 629                               DMA_FROM_DEVICE);
 630         if (ret) {
 631                 cmd->transport_complete_callback = NULL;
 632                 up(&dev->caw_sem);
 633                 return ret;
 634         }
 635         /*
 636          * Unlock of dev->caw_sem to occur in compare_and_write_callback()
 637          * upon MISCOMPARE, or in compare_and_write_done() upon completion
 638          * of WRITE instance user-data.
 639          */
 640         return TCM_NO_SENSE;
 641 }
 642
 643 static int
 644 sbc_set_prot_op_checks(u8 protect, bool fabric_prot, enum target_prot_type prot_type,
 645                        bool is_write, struct se_cmd *cmd)
 646 {
 647         if (is_write) {
 648                 cmd->prot_op = fabric_prot ? TARGET_PROT_DOUT_STRIP :
 649                                protect ? TARGET_PROT_DOUT_PASS :
 650                                TARGET_PROT_DOUT_INSERT;
 651                 switch (protect) {
 652                 case 0x0:
 653                 case 0x3:
 654                         cmd->prot_checks = 0;
 655                         break;
 656                 case 0x1:
 657                 case 0x5:
 658                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 659                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 660                                 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 661                         break;
 662                 case 0x2:
 663                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 664                                 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 665                         break;
 666                 case 0x4:
 667                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 668                         break;
 669                 default:
 670                         pr_err("Unsupported protect field %d\n", protect);
 671                         return -EINVAL;
 672                 }
 673         } else {
 674                 cmd->prot_op = fabric_prot ? TARGET_PROT_DIN_INSERT :
 675                                protect ? TARGET_PROT_DIN_PASS :
 676                                TARGET_PROT_DIN_STRIP;
 677                 switch (protect) {
 678                 case 0x0:
 679                 case 0x1:
 680                 case 0x5:
 681                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 682                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 683                                 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 684                         break;
 685                 case 0x2:
 686                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 687                                 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 688                         break;
 689                 case 0x3:
 690                         cmd->prot_checks = 0;
 691                         break;
 692                 case 0x4:
 693                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 694                         break;
 695                 default:
 696                         pr_err("Unsupported protect field %d\n", protect);
 697                         return -EINVAL;
 698                 }
 699         }
 700
 701         return 0;
 702 }
 703
 704 static sense_reason_t
 705 sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb,
 706                u32 sectors, bool is_write)
 707 {
 708         u8 protect = cdb[1] >> 5;
 709         int sp_ops = cmd->se_sess->sup_prot_ops;
 710         int pi_prot_type = dev->dev_attrib.pi_prot_type;
 711         bool fabric_prot = false;
 712
 713         if (!cmd->t_prot_sg || !cmd->t_prot_nents) {
 714                 if (unlikely(protect &&
 715                     !dev->dev_attrib.pi_prot_type && !cmd->se_sess->sess_prot_type)) {
 716                         pr_err("CDB contains protect bit, but device + fabric does"
 717                                " not advertise PROTECT=1 feature bit\n");
 718                         return TCM_INVALID_CDB_FIELD;
 719                 }
 720                 if (cmd->prot_pto)
 721                         return TCM_NO_SENSE;
 722         }
 723
 724         switch (dev->dev_attrib.pi_prot_type) {
 725         case TARGET_DIF_TYPE3_PROT:
 726                 cmd->reftag_seed = 0xffffffff;
 727                 break;
 728         case TARGET_DIF_TYPE2_PROT:
 729                 if (protect)
 730                         return TCM_INVALID_CDB_FIELD;
 731
 732                 cmd->reftag_seed = cmd->t_task_lba;
 733                 break;
 734         case TARGET_DIF_TYPE1_PROT:
 735                 cmd->reftag_seed = cmd->t_task_lba;
 736                 break;
 737         case TARGET_DIF_TYPE0_PROT:
 738                 /*
 739                  * See if the fabric supports T10-PI, and the session has been
 740                  * configured to allow export PROTECT=1 feature bit with backend
 741                  * devices that don't support T10-PI.
 742                  */
 743                 fabric_prot = is_write ?
 744                               !!(sp_ops & (TARGET_PROT_DOUT_PASS | TARGET_PROT_DOUT_STRIP)) :
 745                               !!(sp_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DIN_INSERT));
 746
 747                 if (fabric_prot && cmd->se_sess->sess_prot_type) {
 748                         pi_prot_type = cmd->se_sess->sess_prot_type;
 749                         break;
 750                 }
 751                 if (!protect)
 752                         return TCM_NO_SENSE;
 753                 /* Fallthrough */
 754         default:
 755                 pr_err("Unable to determine pi_prot_type for CDB: 0x%02x "
 756                        "PROTECT: 0x%02x\n", cdb[0], protect);
 757                 return TCM_INVALID_CDB_FIELD;
 758         }
 759
 760         if (sbc_set_prot_op_checks(protect, fabric_prot, pi_prot_type, is_write, cmd))
 761                 return TCM_INVALID_CDB_FIELD;
 762
 763         cmd->prot_type = pi_prot_type;
 764         cmd->prot_length = dev->prot_length * sectors;
 765
 766         /**
 767          * In case protection information exists over the wire
 768          * we modify command data length to describe pure data.
 769          * The actual transfer length is data length + protection
 770          * length
 771          **/
 772         if (protect)
 773                 cmd->data_length = sectors * dev->dev_attrib.block_size;
 774
 775         pr_debug("%s: prot_type=%d, data_length=%d, prot_length=%d "
 776                  "prot_op=%d prot_checks=%d\n",
 777                  __func__, cmd->prot_type, cmd->data_length, cmd->prot_length,
 778                  cmd->prot_op, cmd->prot_checks);
 779
 780         return TCM_NO_SENSE;
 781 }
 782
 783 static int
 784 sbc_check_dpofua(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb)
 785 {
 786         if (cdb[1] & 0x10) {
 787                 /* see explanation in spc_emulate_modesense */
 788                 if (!target_check_fua(dev)) {
 789                         pr_err("Got CDB: 0x%02x with DPO bit set, but device"
 790                                " does not advertise support for DPO\n", cdb[0]);
 791                         return -EINVAL;
 792                 }
 793         }
 794         if (cdb[1] & 0x8) {
 795                 if (!target_check_fua(dev)) {
 796                         pr_err("Got CDB: 0x%02x with FUA bit set, but device"
 797                                " does not advertise support for FUA write\n",
 798                                cdb[0]);
 799                         return -EINVAL;
 800                 }
 801                 cmd->se_cmd_flags |= SCF_FUA;
 802         }
 803         return 0;
 804 }
 805
 806 sense_reason_t
 807 sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 808 {
 809         struct se_device *dev = cmd->se_dev;
 810         unsigned char *cdb = cmd->t_task_cdb;
 811         unsigned int size;
 812         u32 sectors = 0;
 813         sense_reason_t ret;
 814
 815         cmd->protocol_data = ops;
 816
 817         switch (cdb[0]) {
 818         case READ_6:
 819                 sectors = transport_get_sectors_6(cdb);
 820                 cmd->t_task_lba = transport_lba_21(cdb);
 821                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 822                 cmd->execute_cmd = sbc_execute_rw;
 823                 break;
 824         case READ_10:
 825                 sectors = transport_get_sectors_10(cdb);
 826                 cmd->t_task_lba = transport_lba_32(cdb);
 827
 828                 if (sbc_check_dpofua(dev, cmd, cdb))
 829                         return TCM_INVALID_CDB_FIELD;
 830
 831                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 832                 if (ret)
 833                         return ret;
 834
 835                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 836                 cmd->execute_cmd = sbc_execute_rw;
 837                 break;
 838         case READ_12:
 839                 sectors = transport_get_sectors_12(cdb);
 840                 cmd->t_task_lba = transport_lba_32(cdb);
 841
 842                 if (sbc_check_dpofua(dev, cmd, cdb))
 843                         return TCM_INVALID_CDB_FIELD;
 844
 845                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 846                 if (ret)
 847                         return ret;
 848
 849                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 850                 cmd->execute_cmd = sbc_execute_rw;
 851                 break;
 852         case READ_16:
 853                 sectors = transport_get_sectors_16(cdb);
 854                 cmd->t_task_lba = transport_lba_64(cdb);
 855
 856                 if (sbc_check_dpofua(dev, cmd, cdb))
 857                         return TCM_INVALID_CDB_FIELD;
 858
 859                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 860                 if (ret)
 861                         return ret;
 862
 863                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 864                 cmd->execute_cmd = sbc_execute_rw;
 865                 break;
 866         case WRITE_6:
 867                 sectors = transport_get_sectors_6(cdb);
 868                 cmd->t_task_lba = transport_lba_21(cdb);
 869                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 870                 cmd->execute_cmd = sbc_execute_rw;
 871                 break;
 872         case WRITE_10:
 873         case WRITE_VERIFY:
 874                 sectors = transport_get_sectors_10(cdb);
 875                 cmd->t_task_lba = transport_lba_32(cdb);
 876
 877                 if (sbc_check_dpofua(dev, cmd, cdb))
 878                         return TCM_INVALID_CDB_FIELD;
 879
 880                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 881                 if (ret)
 882                         return ret;
 883
 884                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 885                 cmd->execute_cmd = sbc_execute_rw;
 886                 break;
 887         case WRITE_12:
 888                 sectors = transport_get_sectors_12(cdb);
 889                 cmd->t_task_lba = transport_lba_32(cdb);
 890
 891                 if (sbc_check_dpofua(dev, cmd, cdb))
 892                         return TCM_INVALID_CDB_FIELD;
 893
 894                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 895                 if (ret)
 896                         return ret;
 897
 898                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 899                 cmd->execute_cmd = sbc_execute_rw;
 900                 break;
 901         case WRITE_16:
 902         case WRITE_VERIFY_16:
 903                 sectors = transport_get_sectors_16(cdb);
 904                 cmd->t_task_lba = transport_lba_64(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 XDWRITEREAD_10:
 917                 if (cmd->data_direction != DMA_TO_DEVICE ||
 918                     !(cmd->se_cmd_flags & SCF_BIDI))
 919                         return TCM_INVALID_CDB_FIELD;
 920                 sectors = transport_get_sectors_10(cdb);
 921
 922                 if (sbc_check_dpofua(dev, cmd, cdb))
 923                         return TCM_INVALID_CDB_FIELD;
 924
 925                 cmd->t_task_lba = transport_lba_32(cdb);
 926                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 927
 928                 /*
 929                  * Setup BIDI XOR callback to be run after I/O completion.
 930                  */
 931                 cmd->execute_cmd = sbc_execute_rw;
 932                 cmd->transport_complete_callback = &xdreadwrite_callback;
 933                 break;
 934         case VARIABLE_LENGTH_CMD:
 935         {
 936                 u16 service_action = get_unaligned_be16(&cdb[8]);
 937                 switch (service_action) {
 938                 case XDWRITEREAD_32:
 939                         sectors = transport_get_sectors_32(cdb);
 940
 941                         if (sbc_check_dpofua(dev, cmd, cdb))
 942                                 return TCM_INVALID_CDB_FIELD;
 943                         /*
 944                          * Use WRITE_32 and READ_32 opcodes for the emulated
 945                          * XDWRITE_READ_32 logic.
 946                          */
 947                         cmd->t_task_lba = transport_lba_64_ext(cdb);
 948                         cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 949
 950                         /*
 951                          * Setup BIDI XOR callback to be run during after I/O
 952                          * completion.
 953                          */
 954                         cmd->execute_cmd = sbc_execute_rw;
 955                         cmd->transport_complete_callback = &xdreadwrite_callback;
 956                         break;
 957                 case WRITE_SAME_32:
 958                         sectors = transport_get_sectors_32(cdb);
 959                         if (!sectors) {
 960                                 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
 961                                        " supported\n");
 962                                 return TCM_INVALID_CDB_FIELD;
 963                         }
 964
 965                         size = sbc_get_size(cmd, 1);
 966                         cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
 967
 968                         ret = sbc_setup_write_same(cmd, &cdb[10], ops);
 969                         if (ret)
 970                                 return ret;
 971                         break;
 972                 default:
 973                         pr_err("VARIABLE_LENGTH_CMD service action"
 974                                 " 0x%04x not supported\n", service_action);
 975                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 976                 }
 977                 break;
 978         }
 979         case COMPARE_AND_WRITE:
 980                 if (!dev->dev_attrib.emulate_caw) {
 981                         pr_err_ratelimited("se_device %s/%s (vpd_unit_serial %s) reject COMPARE_AND_WRITE\n",
 982                                            dev->se_hba->backend->ops->name,
 983                                            config_item_name(&dev->dev_group.cg_item),
 984                                            dev->t10_wwn.unit_serial);
 985                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 986                 }
 987                 sectors = cdb[13];
 988                 /*
 989                  * Currently enforce COMPARE_AND_WRITE for a single sector
 990                  */
 991                 if (sectors > 1) {
 992                         pr_err("COMPARE_AND_WRITE contains NoLB: %u greater"
 993                                " than 1\n", sectors);
 994                         return TCM_INVALID_CDB_FIELD;
 995                 }
 996                 if (sbc_check_dpofua(dev, cmd, cdb))
 997                         return TCM_INVALID_CDB_FIELD;
 998
 999                 /*
1000                  * Double size because we have two buffers, note that
1001                  * zero is not an error..
1002                  */
1003                 size = 2 * sbc_get_size(cmd, sectors);
1004                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1005                 cmd->t_task_nolb = sectors;
1006                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE;
1007                 cmd->execute_cmd = sbc_compare_and_write;
1008                 cmd->transport_complete_callback = compare_and_write_callback;
1009                 break;
1010         case READ_CAPACITY:
1011                 size = READ_CAP_LEN;
1012                 cmd->execute_cmd = sbc_emulate_readcapacity;
1013                 break;
1014         case SERVICE_ACTION_IN_16:
1015                 switch (cmd->t_task_cdb[1] & 0x1f) {
1016                 case SAI_READ_CAPACITY_16:
1017                         cmd->execute_cmd = sbc_emulate_readcapacity_16;
1018                         break;
1019                 case SAI_REPORT_REFERRALS:
1020                         cmd->execute_cmd = target_emulate_report_referrals;
1021                         break;
1022                 default:
1023                         pr_err("Unsupported SA: 0x%02x\n",
1024                                 cmd->t_task_cdb[1] & 0x1f);
1025                         return TCM_INVALID_CDB_FIELD;
1026                 }
1027                 size = get_unaligned_be32(&cdb[10]);
1028                 break;
1029         case SYNCHRONIZE_CACHE:
1030         case SYNCHRONIZE_CACHE_16:
1031                 if (cdb[0] == SYNCHRONIZE_CACHE) {
1032                         sectors = transport_get_sectors_10(cdb);
1033                         cmd->t_task_lba = transport_lba_32(cdb);
1034                 } else {
1035                         sectors = transport_get_sectors_16(cdb);
1036                         cmd->t_task_lba = transport_lba_64(cdb);
1037                 }
1038                 if (ops->execute_sync_cache) {
1039                         cmd->execute_cmd = ops->execute_sync_cache;
1040                         goto check_lba;
1041                 }
1042                 size = 0;
1043                 cmd->execute_cmd = sbc_emulate_noop;
1044                 break;
1045         case UNMAP:
1046                 if (!ops->execute_unmap)
1047                         return TCM_UNSUPPORTED_SCSI_OPCODE;
1048
1049                 if (!dev->dev_attrib.emulate_tpu) {
1050                         pr_err("Got UNMAP, but backend device has"
1051                                " emulate_tpu disabled\n");
1052                         return TCM_UNSUPPORTED_SCSI_OPCODE;
1053                 }
1054                 size = get_unaligned_be16(&cdb[7]);
1055                 cmd->execute_cmd = sbc_execute_unmap;
1056                 break;
1057         case WRITE_SAME_16:
1058                 sectors = transport_get_sectors_16(cdb);
1059                 if (!sectors) {
1060                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1061                         return TCM_INVALID_CDB_FIELD;
1062                 }
1063
1064                 size = sbc_get_size(cmd, 1);
1065                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1066
1067                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1068                 if (ret)
1069                         return ret;
1070                 break;
1071         case WRITE_SAME:
1072                 sectors = transport_get_sectors_10(cdb);
1073                 if (!sectors) {
1074                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1075                         return TCM_INVALID_CDB_FIELD;
1076                 }
1077
1078                 size = sbc_get_size(cmd, 1);
1079                 cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
1080
1081                 /*
1082                  * Follow sbcr26 with WRITE_SAME (10) and check for the existence
1083                  * of byte 1 bit 3 UNMAP instead of original reserved field
1084                  */
1085                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1086                 if (ret)
1087                         return ret;
1088                 break;
1089         case VERIFY:
1090         case VERIFY_16:
1091                 size = 0;
1092                 if (cdb[0] == VERIFY) {
1093                         sectors = transport_get_sectors_10(cdb);
1094                         cmd->t_task_lba = transport_lba_32(cdb);
1095                 } else {
1096                         sectors = transport_get_sectors_16(cdb);
1097                         cmd->t_task_lba = transport_lba_64(cdb);
1098                 }
1099                 cmd->execute_cmd = sbc_emulate_noop;
1100                 goto check_lba;
1101         case REZERO_UNIT:
1102         case SEEK_6:
1103         case SEEK_10:
1104                 /*
1105                  * There are still clients out there which use these old SCSI-2
1106                  * commands. This mainly happens when running VMs with legacy
1107                  * guest systems, connected via SCSI command pass-through to
1108                  * iSCSI targets. Make them happy and return status GOOD.
1109                  */
1110                 size = 0;
1111                 cmd->execute_cmd = sbc_emulate_noop;
1112                 break;
1113         case START_STOP:
1114                 size = 0;
1115                 cmd->execute_cmd = sbc_emulate_startstop;
1116                 break;
1117         default:
1118                 ret = spc_parse_cdb(cmd, &size);
1119                 if (ret)
1120                         return ret;
1121         }
1122
1123         /* reject any command that we don't have a handler for */
1124         if (!cmd->execute_cmd)
1125                 return TCM_UNSUPPORTED_SCSI_OPCODE;
1126
1127         if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1128                 unsigned long long end_lba;
1129 check_lba:
1130                 end_lba = dev->transport->get_blocks(dev) + 1;
1131                 if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
1132                     ((cmd->t_task_lba + sectors) > end_lba)) {
1133                         pr_err("cmd exceeds last lba %llu "
1134                                 "(lba %llu, sectors %u)\n",
1135                                 end_lba, cmd->t_task_lba, sectors);
1136                         return TCM_ADDRESS_OUT_OF_RANGE;
1137                 }
1138
1139                 if (!(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE))
1140                         size = sbc_get_size(cmd, sectors);
1141         }
1142
1143         return target_cmd_size_check(cmd, size);
1144 }
1145 EXPORT_SYMBOL(sbc_parse_cdb);
1146
1147 u32 sbc_get_device_type(struct se_device *dev)
1148 {
1149         return TYPE_DISK;
1150 }
1151 EXPORT_SYMBOL(sbc_get_device_type);
1152
1153 static sense_reason_t
1154 sbc_execute_unmap(struct se_cmd *cmd)
1155 {
1156         struct sbc_ops *ops = cmd->protocol_data;
1157         struct se_device *dev = cmd->se_dev;
1158         unsigned char *buf, *ptr = NULL;
1159         sector_t lba;
1160         int size;
1161         u32 range;
1162         sense_reason_t ret = 0;
1163         int dl, bd_dl;
1164
1165         /* We never set ANC_SUP */
1166         if (cmd->t_task_cdb[1])
1167                 return TCM_INVALID_CDB_FIELD;
1168
1169         if (cmd->data_length == 0) {
1170                 target_complete_cmd(cmd, SAM_STAT_GOOD);
1171                 return 0;
1172         }
1173
1174         if (cmd->data_length < 8) {
1175                 pr_warn("UNMAP parameter list length %u too small\n",
1176                         cmd->data_length);
1177                 return TCM_PARAMETER_LIST_LENGTH_ERROR;
1178         }
1179
1180         buf = transport_kmap_data_sg(cmd);
1181         if (!buf)
1182                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1183
1184         dl = get_unaligned_be16(&buf[0]);
1185         bd_dl = get_unaligned_be16(&buf[2]);
1186
1187         size = cmd->data_length - 8;
1188         if (bd_dl > size)
1189                 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
1190                         cmd->data_length, bd_dl);
1191         else
1192                 size = bd_dl;
1193
1194         if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
1195                 ret = TCM_INVALID_PARAMETER_LIST;
1196                 goto err;
1197         }
1198
1199         /* First UNMAP block descriptor starts at 8 byte offset */
1200         ptr = &buf[8];
1201         pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
1202                 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
1203
1204         while (size >= 16) {
1205                 lba = get_unaligned_be64(&ptr[0]);
1206                 range = get_unaligned_be32(&ptr[8]);
1207                 pr_debug("UNMAP: Using lba: %llu and range: %u\n",
1208                                  (unsigned long long)lba, range);
1209
1210                 if (range > dev->dev_attrib.max_unmap_lba_count) {
1211                         ret = TCM_INVALID_PARAMETER_LIST;
1212                         goto err;
1213                 }
1214
1215                 if (lba + range > dev->transport->get_blocks(dev) + 1) {
1216                         ret = TCM_ADDRESS_OUT_OF_RANGE;
1217                         goto err;
1218                 }
1219
1220                 if (range) {
1221                         ret = ops->execute_unmap(cmd, lba, range);
1222                         if (ret)
1223                                 goto err;
1224                 }
1225
1226                 ptr += 16;
1227                 size -= 16;
1228         }
1229
1230 err:
1231         transport_kunmap_data_sg(cmd);
1232         if (!ret)
1233                 target_complete_cmd(cmd, GOOD);
1234         return ret;
1235 }
1236
1237 void
1238 sbc_dif_generate(struct se_cmd *cmd)
1239 {
1240         struct se_device *dev = cmd->se_dev;
1241         struct t10_pi_tuple *sdt;
1242         struct scatterlist *dsg = cmd->t_data_sg, *psg;
1243         sector_t sector = cmd->t_task_lba;
1244         void *daddr, *paddr;
1245         int i, j, offset = 0;
1246         unsigned int block_size = dev->dev_attrib.block_size;
1247
1248         for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1249                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1250                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1251
1252                 for (j = 0; j < psg->length;
1253                                 j += sizeof(*sdt)) {
1254                         __u16 crc;
1255                         unsigned int avail;
1256
1257                         if (offset >= dsg->length) {
1258                                 offset -= dsg->length;
1259                                 kunmap_atomic(daddr - dsg->offset);
1260                                 dsg = sg_next(dsg);
1261                                 if (!dsg) {
1262                                         kunmap_atomic(paddr - psg->offset);
1263                                         return;
1264                                 }
1265                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1266                         }
1267
1268                         sdt = paddr + j;
1269                         avail = min(block_size, dsg->length - offset);
1270                         crc = crc_t10dif(daddr + offset, avail);
1271                         if (avail < block_size) {
1272                                 kunmap_atomic(daddr - dsg->offset);
1273                                 dsg = sg_next(dsg);
1274                                 if (!dsg) {
1275                                         kunmap_atomic(paddr - psg->offset);
1276                                         return;
1277                                 }
1278                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1279                                 offset = block_size - avail;
1280                                 crc = crc_t10dif_update(crc, daddr, offset);
1281                         } else {
1282                                 offset += block_size;
1283                         }
1284
1285                         sdt->guard_tag = cpu_to_be16(crc);
1286                         if (cmd->prot_type == TARGET_DIF_TYPE1_PROT)
1287                                 sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
1288                         sdt->app_tag = 0;
1289
1290                         pr_debug("DIF %s INSERT sector: %llu guard_tag: 0x%04x"
1291                                  " app_tag: 0x%04x ref_tag: %u\n",
1292                                  (cmd->data_direction == DMA_TO_DEVICE) ?
1293                                  "WRITE" : "READ", (unsigned long long)sector,
1294                                  sdt->guard_tag, sdt->app_tag,
1295                                  be32_to_cpu(sdt->ref_tag));
1296
1297                         sector++;
1298                 }
1299
1300                 kunmap_atomic(daddr - dsg->offset);
1301                 kunmap_atomic(paddr - psg->offset);
1302         }
1303 }
1304
1305 static sense_reason_t
1306 sbc_dif_v1_verify(struct se_cmd *cmd, struct t10_pi_tuple *sdt,
1307                   __u16 crc, sector_t sector, unsigned int ei_lba)
1308 {
1309         __be16 csum;
1310
1311         if (!(cmd->prot_checks & TARGET_DIF_CHECK_GUARD))
1312                 goto check_ref;
1313
1314         csum = cpu_to_be16(crc);
1315
1316         if (sdt->guard_tag != csum) {
1317                 pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x"
1318                         " csum 0x%04x\n", (unsigned long long)sector,
1319                         be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
1320                 return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
1321         }
1322
1323 check_ref:
1324         if (!(cmd->prot_checks & TARGET_DIF_CHECK_REFTAG))
1325                 return 0;
1326
1327         if (cmd->prot_type == TARGET_DIF_TYPE1_PROT &&
1328             be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
1329                 pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x"
1330                        " sector MSB: 0x%08x\n", (unsigned long long)sector,
1331                        be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff));
1332                 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1333         }
1334
1335         if (cmd->prot_type == TARGET_DIF_TYPE2_PROT &&
1336             be32_to_cpu(sdt->ref_tag) != ei_lba) {
1337                 pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x"
1338                        " ei_lba: 0x%08x\n", (unsigned long long)sector,
1339                         be32_to_cpu(sdt->ref_tag), ei_lba);
1340                 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1341         }
1342
1343         return 0;
1344 }
1345
1346 void sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read,
1347                        struct scatterlist *sg, int sg_off)
1348 {
1349         struct se_device *dev = cmd->se_dev;
1350         struct scatterlist *psg;
1351         void *paddr, *addr;
1352         unsigned int i, len, left;
1353         unsigned int offset = sg_off;
1354
1355         if (!sg)
1356                 return;
1357
1358         left = sectors * dev->prot_length;
1359
1360         for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1361                 unsigned int psg_len, copied = 0;
1362
1363                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1364                 psg_len = min(left, psg->length);
1365                 while (psg_len) {
1366                         len = min(psg_len, sg->length - offset);
1367                         addr = kmap_atomic(sg_page(sg)) + sg->offset + offset;
1368
1369                         if (read)
1370                                 memcpy(paddr + copied, addr, len);
1371                         else
1372                                 memcpy(addr, paddr + copied, len);
1373
1374                         left -= len;
1375                         offset += len;
1376                         copied += len;
1377                         psg_len -= len;
1378
1379                         kunmap_atomic(addr - sg->offset - offset);
1380
1381                         if (offset >= sg->length) {
1382                                 sg = sg_next(sg);
1383                                 offset = 0;
1384                         }
1385                 }
1386                 kunmap_atomic(paddr - psg->offset);
1387         }
1388 }
1389 EXPORT_SYMBOL(sbc_dif_copy_prot);
1390
1391 sense_reason_t
1392 sbc_dif_verify(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1393                unsigned int ei_lba, struct scatterlist *psg, int psg_off)
1394 {
1395         struct se_device *dev = cmd->se_dev;
1396         struct t10_pi_tuple *sdt;
1397         struct scatterlist *dsg = cmd->t_data_sg;
1398         sector_t sector = start;
1399         void *daddr, *paddr;
1400         int i;
1401         sense_reason_t rc;
1402         int dsg_off = 0;
1403         unsigned int block_size = dev->dev_attrib.block_size;
1404
1405         for (; psg && sector < start + sectors; psg = sg_next(psg)) {
1406                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1407                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1408
1409                 for (i = psg_off; i < psg->length &&
1410                                 sector < start + sectors;
1411                                 i += sizeof(*sdt)) {
1412                         __u16 crc;
1413                         unsigned int avail;
1414
1415                         if (dsg_off >= dsg->length) {
1416                                 dsg_off -= dsg->length;
1417                                 kunmap_atomic(daddr - dsg->offset);
1418                                 dsg = sg_next(dsg);
1419                                 if (!dsg) {
1420                                         kunmap_atomic(paddr - psg->offset);
1421                                         return 0;
1422                                 }
1423                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1424                         }
1425
1426                         sdt = paddr + i;
1427
1428                         pr_debug("DIF READ sector: %llu guard_tag: 0x%04x"
1429                                  " app_tag: 0x%04x ref_tag: %u\n",
1430                                  (unsigned long long)sector, sdt->guard_tag,
1431                                  sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1432
1433                         if (sdt->app_tag == T10_PI_APP_ESCAPE) {
1434                                 dsg_off += block_size;
1435                                 goto next;
1436                         }
1437
1438                         avail = min(block_size, dsg->length - dsg_off);
1439                         crc = crc_t10dif(daddr + dsg_off, avail);
1440                         if (avail < block_size) {
1441                                 kunmap_atomic(daddr - dsg->offset);
1442                                 dsg = sg_next(dsg);
1443                                 if (!dsg) {
1444                                         kunmap_atomic(paddr - psg->offset);
1445                                         return 0;
1446                                 }
1447                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1448                                 dsg_off = block_size - avail;
1449                                 crc = crc_t10dif_update(crc, daddr, dsg_off);
1450                         } else {
1451                                 dsg_off += block_size;
1452                         }
1453
1454                         rc = sbc_dif_v1_verify(cmd, sdt, crc, sector, ei_lba);
1455                         if (rc) {
1456                                 kunmap_atomic(daddr - dsg->offset);
1457                                 kunmap_atomic(paddr - psg->offset);
1458                                 cmd->bad_sector = sector;
1459                                 return rc;
1460                         }
1461 next:
1462                         sector++;
1463                         ei_lba++;
1464                 }
1465
1466                 psg_off = 0;
1467                 kunmap_atomic(daddr - dsg->offset);
1468                 kunmap_atomic(paddr - psg->offset);
1469         }
1470
1471         return 0;
1472 }
1473 EXPORT_SYMBOL(sbc_dif_verify);