drivers/target/target_core_sbc.c

   1 /*
   2  * SCSI Block Commands (SBC) parsing and emulation.
   3  *
   4  * (c) Copyright 2002-2012 RisingTide Systems LLC.
   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 <asm/unaligned.h>
  27 #include <scsi/scsi.h>
  28
  29 #include <target/target_core_base.h>
  30 #include <target/target_core_backend.h>
  31 #include <target/target_core_fabric.h>
  32
  33 #include "target_core_internal.h"
  34 #include "target_core_ua.h"
  35
  36
  37 static sense_reason_t
  38 sbc_emulate_readcapacity(struct se_cmd *cmd)
  39 {
  40         struct se_device *dev = cmd->se_dev;
  41         unsigned char *cdb = cmd->t_task_cdb;
  42         unsigned long long blocks_long = dev->transport->get_blocks(dev);
  43         unsigned char *rbuf;
  44         unsigned char buf[8];
  45         u32 blocks;
  46
  47         /*
  48          * SBC-2 says:
  49          *   If the PMI bit is set to zero and the LOGICAL BLOCK
  50          *   ADDRESS field is not set to zero, the device server shall
  51          *   terminate the command with CHECK CONDITION status with
  52          *   the sense key set to ILLEGAL REQUEST and the additional
  53          *   sense code set to INVALID FIELD IN CDB.
  54          *
  55          * In SBC-3, these fields are obsolete, but some SCSI
  56          * compliance tests actually check this, so we might as well
  57          * follow SBC-2.
  58          */
  59         if (!(cdb[8] & 1) && !!(cdb[2] | cdb[3] | cdb[4] | cdb[5]))
  60                 return TCM_INVALID_CDB_FIELD;
  61
  62         if (blocks_long >= 0x00000000ffffffff)
  63                 blocks = 0xffffffff;
  64         else
  65                 blocks = (u32)blocks_long;
  66
  67         buf[0] = (blocks >> 24) & 0xff;
  68         buf[1] = (blocks >> 16) & 0xff;
  69         buf[2] = (blocks >> 8) & 0xff;
  70         buf[3] = blocks & 0xff;
  71         buf[4] = (dev->dev_attrib.block_size >> 24) & 0xff;
  72         buf[5] = (dev->dev_attrib.block_size >> 16) & 0xff;
  73         buf[6] = (dev->dev_attrib.block_size >> 8) & 0xff;
  74         buf[7] = dev->dev_attrib.block_size & 0xff;
  75
  76         rbuf = transport_kmap_data_sg(cmd);
  77         if (rbuf) {
  78                 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
  79                 transport_kunmap_data_sg(cmd);
  80         }
  81
  82         target_complete_cmd(cmd, GOOD);
  83         return 0;
  84 }
  85
  86 static sense_reason_t
  87 sbc_emulate_readcapacity_16(struct se_cmd *cmd)
  88 {
  89         struct se_device *dev = cmd->se_dev;
  90         unsigned char *rbuf;
  91         unsigned char buf[32];
  92         unsigned long long blocks = dev->transport->get_blocks(dev);
  93
  94         memset(buf, 0, sizeof(buf));
  95         buf[0] = (blocks >> 56) & 0xff;
  96         buf[1] = (blocks >> 48) & 0xff;
  97         buf[2] = (blocks >> 40) & 0xff;
  98         buf[3] = (blocks >> 32) & 0xff;
  99         buf[4] = (blocks >> 24) & 0xff;
 100         buf[5] = (blocks >> 16) & 0xff;
 101         buf[6] = (blocks >> 8) & 0xff;
 102         buf[7] = blocks & 0xff;
 103         buf[8] = (dev->dev_attrib.block_size >> 24) & 0xff;
 104         buf[9] = (dev->dev_attrib.block_size >> 16) & 0xff;
 105         buf[10] = (dev->dev_attrib.block_size >> 8) & 0xff;
 106         buf[11] = dev->dev_attrib.block_size & 0xff;
 107         /*
 108          * Set Thin Provisioning Enable bit following sbc3r22 in section
 109          * READ CAPACITY (16) byte 14 if emulate_tpu or emulate_tpws is enabled.
 110          */
 111         if (dev->dev_attrib.emulate_tpu || dev->dev_attrib.emulate_tpws)
 112                 buf[14] = 0x80;
 113
 114         rbuf = transport_kmap_data_sg(cmd);
 115         if (rbuf) {
 116                 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
 117                 transport_kunmap_data_sg(cmd);
 118         }
 119
 120         target_complete_cmd(cmd, GOOD);
 121         return 0;
 122 }
 123
 124 sector_t sbc_get_write_same_sectors(struct se_cmd *cmd)
 125 {
 126         u32 num_blocks;
 127
 128         if (cmd->t_task_cdb[0] == WRITE_SAME)
 129                 num_blocks = get_unaligned_be16(&cmd->t_task_cdb[7]);
 130         else if (cmd->t_task_cdb[0] == WRITE_SAME_16)
 131                 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[10]);
 132         else /* WRITE_SAME_32 via VARIABLE_LENGTH_CMD */
 133                 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[28]);
 134
 135         /*
 136          * Use the explicit range when non zero is supplied, otherwise calculate
 137          * the remaining range based on ->get_blocks() - starting LBA.
 138          */
 139         if (num_blocks)
 140                 return num_blocks;
 141
 142         return cmd->se_dev->transport->get_blocks(cmd->se_dev) -
 143                 cmd->t_task_lba + 1;
 144 }
 145 EXPORT_SYMBOL(sbc_get_write_same_sectors);
 146
 147 static sense_reason_t
 148 sbc_emulate_noop(struct se_cmd *cmd)
 149 {
 150         target_complete_cmd(cmd, GOOD);
 151         return 0;
 152 }
 153
 154 static inline u32 sbc_get_size(struct se_cmd *cmd, u32 sectors)
 155 {
 156         return cmd->se_dev->dev_attrib.block_size * sectors;
 157 }
 158
 159 static int sbc_check_valid_sectors(struct se_cmd *cmd)
 160 {
 161         struct se_device *dev = cmd->se_dev;
 162         unsigned long long end_lba;
 163         u32 sectors;
 164
 165         sectors = cmd->data_length / dev->dev_attrib.block_size;
 166         end_lba = dev->transport->get_blocks(dev) + 1;
 167
 168         if (cmd->t_task_lba + sectors > end_lba) {
 169                 pr_err("target: lba %llu, sectors %u exceeds end lba %llu\n",
 170                         cmd->t_task_lba, sectors, end_lba);
 171                 return -EINVAL;
 172         }
 173
 174         return 0;
 175 }
 176
 177 static inline u32 transport_get_sectors_6(unsigned char *cdb)
 178 {
 179         /*
 180          * Use 8-bit sector value.  SBC-3 says:
 181          *
 182          *   A TRANSFER LENGTH field set to zero specifies that 256
 183          *   logical blocks shall be written.  Any other value
 184          *   specifies the number of logical blocks that shall be
 185          *   written.
 186          */
 187         return cdb[4] ? : 256;
 188 }
 189
 190 static inline u32 transport_get_sectors_10(unsigned char *cdb)
 191 {
 192         return (u32)(cdb[7] << 8) + cdb[8];
 193 }
 194
 195 static inline u32 transport_get_sectors_12(unsigned char *cdb)
 196 {
 197         return (u32)(cdb[6] << 24) + (cdb[7] << 16) + (cdb[8] << 8) + cdb[9];
 198 }
 199
 200 static inline u32 transport_get_sectors_16(unsigned char *cdb)
 201 {
 202         return (u32)(cdb[10] << 24) + (cdb[11] << 16) +
 203                     (cdb[12] << 8) + cdb[13];
 204 }
 205
 206 /*
 207  * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
 208  */
 209 static inline u32 transport_get_sectors_32(unsigned char *cdb)
 210 {
 211         return (u32)(cdb[28] << 24) + (cdb[29] << 16) +
 212                     (cdb[30] << 8) + cdb[31];
 213
 214 }
 215
 216 static inline u32 transport_lba_21(unsigned char *cdb)
 217 {
 218         return ((cdb[1] & 0x1f) << 16) | (cdb[2] << 8) | cdb[3];
 219 }
 220
 221 static inline u32 transport_lba_32(unsigned char *cdb)
 222 {
 223         return (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
 224 }
 225
 226 static inline unsigned long long transport_lba_64(unsigned char *cdb)
 227 {
 228         unsigned int __v1, __v2;
 229
 230         __v1 = (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
 231         __v2 = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
 232
 233         return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
 234 }
 235
 236 /*
 237  * For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs
 238  */
 239 static inline unsigned long long transport_lba_64_ext(unsigned char *cdb)
 240 {
 241         unsigned int __v1, __v2;
 242
 243         __v1 = (cdb[12] << 24) | (cdb[13] << 16) | (cdb[14] << 8) | cdb[15];
 244         __v2 = (cdb[16] << 24) | (cdb[17] << 16) | (cdb[18] << 8) | cdb[19];
 245
 246         return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
 247 }
 248
 249 static sense_reason_t
 250 sbc_setup_write_same(struct se_cmd *cmd, unsigned char *flags, struct sbc_ops *ops)
 251 {
 252         unsigned int sectors = sbc_get_write_same_sectors(cmd);
 253
 254         if ((flags[0] & 0x04) || (flags[0] & 0x02)) {
 255                 pr_err("WRITE_SAME PBDATA and LBDATA"
 256                         " bits not supported for Block Discard"
 257                         " Emulation\n");
 258                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 259         }
 260         if (sectors > cmd->se_dev->dev_attrib.max_write_same_len) {
 261                 pr_warn("WRITE_SAME sectors: %u exceeds max_write_same_len: %u\n",
 262                         sectors, cmd->se_dev->dev_attrib.max_write_same_len);
 263                 return TCM_INVALID_CDB_FIELD;
 264         }
 265         /*
 266          * Special case for WRITE_SAME w/ UNMAP=1 that ends up getting
 267          * translated into block discard requests within backend code.
 268          */
 269         if (flags[0] & 0x08) {
 270                 if (!ops->execute_write_same_unmap)
 271                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 272
 273                 cmd->execute_cmd = ops->execute_write_same_unmap;
 274                 return 0;
 275         }
 276         if (!ops->execute_write_same)
 277                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 278
 279         cmd->execute_cmd = ops->execute_write_same;
 280         return 0;
 281 }
 282
 283 static void xdreadwrite_callback(struct se_cmd *cmd)
 284 {
 285         unsigned char *buf, *addr;
 286         struct scatterlist *sg;
 287         unsigned int offset;
 288         int i;
 289         int count;
 290         /*
 291          * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
 292          *
 293          * 1) read the specified logical block(s);
 294          * 2) transfer logical blocks from the data-out buffer;
 295          * 3) XOR the logical blocks transferred from the data-out buffer with
 296          *    the logical blocks read, storing the resulting XOR data in a buffer;
 297          * 4) if the DISABLE WRITE bit is set to zero, then write the logical
 298          *    blocks transferred from the data-out buffer; and
 299          * 5) transfer the resulting XOR data to the data-in buffer.
 300          */
 301         buf = kmalloc(cmd->data_length, GFP_KERNEL);
 302         if (!buf) {
 303                 pr_err("Unable to allocate xor_callback buf\n");
 304                 return;
 305         }
 306         /*
 307          * Copy the scatterlist WRITE buffer located at cmd->t_data_sg
 308          * into the locally allocated *buf
 309          */
 310         sg_copy_to_buffer(cmd->t_data_sg,
 311                           cmd->t_data_nents,
 312                           buf,
 313                           cmd->data_length);
 314
 315         /*
 316          * Now perform the XOR against the BIDI read memory located at
 317          * cmd->t_mem_bidi_list
 318          */
 319
 320         offset = 0;
 321         for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
 322                 addr = kmap_atomic(sg_page(sg));
 323                 if (!addr)
 324                         goto out;
 325
 326                 for (i = 0; i < sg->length; i++)
 327                         *(addr + sg->offset + i) ^= *(buf + offset + i);
 328
 329                 offset += sg->length;
 330                 kunmap_atomic(addr);
 331         }
 332
 333 out:
 334         kfree(buf);
 335 }
 336
 337 sense_reason_t
 338 sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 339 {
 340         struct se_device *dev = cmd->se_dev;
 341         unsigned char *cdb = cmd->t_task_cdb;
 342         unsigned int size;
 343         u32 sectors = 0;
 344         sense_reason_t ret;
 345
 346         switch (cdb[0]) {
 347         case READ_6:
 348                 sectors = transport_get_sectors_6(cdb);
 349                 cmd->t_task_lba = transport_lba_21(cdb);
 350                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 351                 cmd->execute_cmd = ops->execute_rw;
 352                 break;
 353         case READ_10:
 354                 sectors = transport_get_sectors_10(cdb);
 355                 cmd->t_task_lba = transport_lba_32(cdb);
 356                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 357                 cmd->execute_cmd = ops->execute_rw;
 358                 break;
 359         case READ_12:
 360                 sectors = transport_get_sectors_12(cdb);
 361                 cmd->t_task_lba = transport_lba_32(cdb);
 362                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 363                 cmd->execute_cmd = ops->execute_rw;
 364                 break;
 365         case READ_16:
 366                 sectors = transport_get_sectors_16(cdb);
 367                 cmd->t_task_lba = transport_lba_64(cdb);
 368                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 369                 cmd->execute_cmd = ops->execute_rw;
 370                 break;
 371         case WRITE_6:
 372                 sectors = transport_get_sectors_6(cdb);
 373                 cmd->t_task_lba = transport_lba_21(cdb);
 374                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 375                 cmd->execute_cmd = ops->execute_rw;
 376                 break;
 377         case WRITE_10:
 378         case WRITE_VERIFY:
 379                 sectors = transport_get_sectors_10(cdb);
 380                 cmd->t_task_lba = transport_lba_32(cdb);
 381                 if (cdb[1] & 0x8)
 382                         cmd->se_cmd_flags |= SCF_FUA;
 383                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 384                 cmd->execute_cmd = ops->execute_rw;
 385                 break;
 386         case WRITE_12:
 387                 sectors = transport_get_sectors_12(cdb);
 388                 cmd->t_task_lba = transport_lba_32(cdb);
 389                 if (cdb[1] & 0x8)
 390                         cmd->se_cmd_flags |= SCF_FUA;
 391                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 392                 cmd->execute_cmd = ops->execute_rw;
 393                 break;
 394         case WRITE_16:
 395                 sectors = transport_get_sectors_16(cdb);
 396                 cmd->t_task_lba = transport_lba_64(cdb);
 397                 if (cdb[1] & 0x8)
 398                         cmd->se_cmd_flags |= SCF_FUA;
 399                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 400                 cmd->execute_cmd = ops->execute_rw;
 401                 break;
 402         case XDWRITEREAD_10:
 403                 if (cmd->data_direction != DMA_TO_DEVICE ||
 404                     !(cmd->se_cmd_flags & SCF_BIDI))
 405                         return TCM_INVALID_CDB_FIELD;
 406                 sectors = transport_get_sectors_10(cdb);
 407
 408                 cmd->t_task_lba = transport_lba_32(cdb);
 409                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 410
 411                 /*
 412                  * Setup BIDI XOR callback to be run after I/O completion.
 413                  */
 414                 cmd->execute_cmd = ops->execute_rw;
 415                 cmd->transport_complete_callback = &xdreadwrite_callback;
 416                 if (cdb[1] & 0x8)
 417                         cmd->se_cmd_flags |= SCF_FUA;
 418                 break;
 419         case VARIABLE_LENGTH_CMD:
 420         {
 421                 u16 service_action = get_unaligned_be16(&cdb[8]);
 422                 switch (service_action) {
 423                 case XDWRITEREAD_32:
 424                         sectors = transport_get_sectors_32(cdb);
 425
 426                         /*
 427                          * Use WRITE_32 and READ_32 opcodes for the emulated
 428                          * XDWRITE_READ_32 logic.
 429                          */
 430                         cmd->t_task_lba = transport_lba_64_ext(cdb);
 431                         cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 432
 433                         /*
 434                          * Setup BIDI XOR callback to be run during after I/O
 435                          * completion.
 436                          */
 437                         cmd->execute_cmd = ops->execute_rw;
 438                         cmd->transport_complete_callback = &xdreadwrite_callback;
 439                         if (cdb[1] & 0x8)
 440                                 cmd->se_cmd_flags |= SCF_FUA;
 441                         break;
 442                 case WRITE_SAME_32:
 443                         sectors = transport_get_sectors_32(cdb);
 444                         if (!sectors) {
 445                                 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
 446                                        " supported\n");
 447                                 return TCM_INVALID_CDB_FIELD;
 448                         }
 449
 450                         size = sbc_get_size(cmd, 1);
 451                         cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
 452
 453                         ret = sbc_setup_write_same(cmd, &cdb[10], ops);
 454                         if (ret)
 455                                 return ret;
 456                         break;
 457                 default:
 458                         pr_err("VARIABLE_LENGTH_CMD service action"
 459                                 " 0x%04x not supported\n", service_action);
 460                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 461                 }
 462                 break;
 463         }
 464         case READ_CAPACITY:
 465                 size = READ_CAP_LEN;
 466                 cmd->execute_cmd = sbc_emulate_readcapacity;
 467                 break;
 468         case SERVICE_ACTION_IN:
 469                 switch (cmd->t_task_cdb[1] & 0x1f) {
 470                 case SAI_READ_CAPACITY_16:
 471                         cmd->execute_cmd = sbc_emulate_readcapacity_16;
 472                         break;
 473                 default:
 474                         pr_err("Unsupported SA: 0x%02x\n",
 475                                 cmd->t_task_cdb[1] & 0x1f);
 476                         return TCM_INVALID_CDB_FIELD;
 477                 }
 478                 size = (cdb[10] << 24) | (cdb[11] << 16) |
 479                        (cdb[12] << 8) | cdb[13];
 480                 break;
 481         case SYNCHRONIZE_CACHE:
 482         case SYNCHRONIZE_CACHE_16:
 483                 if (!ops->execute_sync_cache) {
 484                         size = 0;
 485                         cmd->execute_cmd = sbc_emulate_noop;
 486                         break;
 487                 }
 488
 489                 /*
 490                  * Extract LBA and range to be flushed for emulated SYNCHRONIZE_CACHE
 491                  */
 492                 if (cdb[0] == SYNCHRONIZE_CACHE) {
 493                         sectors = transport_get_sectors_10(cdb);
 494                         cmd->t_task_lba = transport_lba_32(cdb);
 495                 } else {
 496                         sectors = transport_get_sectors_16(cdb);
 497                         cmd->t_task_lba = transport_lba_64(cdb);
 498                 }
 499
 500                 size = sbc_get_size(cmd, sectors);
 501
 502                 /*
 503                  * Check to ensure that LBA + Range does not exceed past end of
 504                  * device for IBLOCK and FILEIO ->do_sync_cache() backend calls
 505                  */
 506                 if (cmd->t_task_lba || sectors) {
 507                         if (sbc_check_valid_sectors(cmd) < 0)
 508                                 return TCM_ADDRESS_OUT_OF_RANGE;
 509                 }
 510                 cmd->execute_cmd = ops->execute_sync_cache;
 511                 break;
 512         case UNMAP:
 513                 if (!ops->execute_unmap)
 514                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 515
 516                 size = get_unaligned_be16(&cdb[7]);
 517                 cmd->execute_cmd = ops->execute_unmap;
 518                 break;
 519         case WRITE_SAME_16:
 520                 sectors = transport_get_sectors_16(cdb);
 521                 if (!sectors) {
 522                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
 523                         return TCM_INVALID_CDB_FIELD;
 524                 }
 525
 526                 size = sbc_get_size(cmd, 1);
 527                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
 528
 529                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
 530                 if (ret)
 531                         return ret;
 532                 break;
 533         case WRITE_SAME:
 534                 sectors = transport_get_sectors_10(cdb);
 535                 if (!sectors) {
 536                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
 537                         return TCM_INVALID_CDB_FIELD;
 538                 }
 539
 540                 size = sbc_get_size(cmd, 1);
 541                 cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
 542
 543                 /*
 544                  * Follow sbcr26 with WRITE_SAME (10) and check for the existence
 545                  * of byte 1 bit 3 UNMAP instead of original reserved field
 546                  */
 547                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
 548                 if (ret)
 549                         return ret;
 550                 break;
 551         case VERIFY:
 552                 size = 0;
 553                 cmd->execute_cmd = sbc_emulate_noop;
 554                 break;
 555         case REZERO_UNIT:
 556         case SEEK_6:
 557         case SEEK_10:
 558                 /*
 559                  * There are still clients out there which use these old SCSI-2
 560                  * commands. This mainly happens when running VMs with legacy
 561                  * guest systems, connected via SCSI command pass-through to
 562                  * iSCSI targets. Make them happy and return status GOOD.
 563                  */
 564                 size = 0;
 565                 cmd->execute_cmd = sbc_emulate_noop;
 566                 break;
 567         default:
 568                 ret = spc_parse_cdb(cmd, &size);
 569                 if (ret)
 570                         return ret;
 571         }
 572
 573         /* reject any command that we don't have a handler for */
 574         if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) && !cmd->execute_cmd)
 575                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 576
 577         if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
 578                 unsigned long long end_lba;
 579
 580                 if (sectors > dev->dev_attrib.fabric_max_sectors) {
 581                         printk_ratelimited(KERN_ERR "SCSI OP %02xh with too"
 582                                 " big sectors %u exceeds fabric_max_sectors:"
 583                                 " %u\n", cdb[0], sectors,
 584                                 dev->dev_attrib.fabric_max_sectors);
 585                         return TCM_INVALID_CDB_FIELD;
 586                 }
 587                 if (sectors > dev->dev_attrib.hw_max_sectors) {
 588                         printk_ratelimited(KERN_ERR "SCSI OP %02xh with too"
 589                                 " big sectors %u exceeds backend hw_max_sectors:"
 590                                 " %u\n", cdb[0], sectors,
 591                                 dev->dev_attrib.hw_max_sectors);
 592                         return TCM_INVALID_CDB_FIELD;
 593                 }
 594
 595                 end_lba = dev->transport->get_blocks(dev) + 1;
 596                 if (cmd->t_task_lba + sectors > end_lba) {
 597                         pr_err("cmd exceeds last lba %llu "
 598                                 "(lba %llu, sectors %u)\n",
 599                                 end_lba, cmd->t_task_lba, sectors);
 600                         return TCM_ADDRESS_OUT_OF_RANGE;
 601                 }
 602
 603                 size = sbc_get_size(cmd, sectors);
 604         }
 605
 606         return target_cmd_size_check(cmd, size);
 607 }
 608 EXPORT_SYMBOL(sbc_parse_cdb);
 609
 610 u32 sbc_get_device_type(struct se_device *dev)
 611 {
 612         return TYPE_DISK;
 613 }
 614 EXPORT_SYMBOL(sbc_get_device_type);
 615
 616 sense_reason_t
 617 sbc_execute_unmap(struct se_cmd *cmd,
 618         sense_reason_t (*do_unmap_fn)(struct se_cmd *, void *,
 619                                       sector_t, sector_t),
 620         void *priv)
 621 {
 622         struct se_device *dev = cmd->se_dev;
 623         unsigned char *buf, *ptr = NULL;
 624         sector_t lba;
 625         int size;
 626         u32 range;
 627         sense_reason_t ret = 0;
 628         int dl, bd_dl;
 629
 630         /* We never set ANC_SUP */
 631         if (cmd->t_task_cdb[1])
 632                 return TCM_INVALID_CDB_FIELD;
 633
 634         if (cmd->data_length == 0) {
 635                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 636                 return 0;
 637         }
 638
 639         if (cmd->data_length < 8) {
 640                 pr_warn("UNMAP parameter list length %u too small\n",
 641                         cmd->data_length);
 642                 return TCM_PARAMETER_LIST_LENGTH_ERROR;
 643         }
 644
 645         buf = transport_kmap_data_sg(cmd);
 646         if (!buf)
 647                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 648
 649         dl = get_unaligned_be16(&buf[0]);
 650         bd_dl = get_unaligned_be16(&buf[2]);
 651
 652         size = cmd->data_length - 8;
 653         if (bd_dl > size)
 654                 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
 655                         cmd->data_length, bd_dl);
 656         else
 657                 size = bd_dl;
 658
 659         if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
 660                 ret = TCM_INVALID_PARAMETER_LIST;
 661                 goto err;
 662         }
 663
 664         /* First UNMAP block descriptor starts at 8 byte offset */
 665         ptr = &buf[8];
 666         pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
 667                 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
 668
 669         while (size >= 16) {
 670                 lba = get_unaligned_be64(&ptr[0]);
 671                 range = get_unaligned_be32(&ptr[8]);
 672                 pr_debug("UNMAP: Using lba: %llu and range: %u\n",
 673                                  (unsigned long long)lba, range);
 674
 675                 if (range > dev->dev_attrib.max_unmap_lba_count) {
 676                         ret = TCM_INVALID_PARAMETER_LIST;
 677                         goto err;
 678                 }
 679
 680                 if (lba + range > dev->transport->get_blocks(dev) + 1) {
 681                         ret = TCM_ADDRESS_OUT_OF_RANGE;
 682                         goto err;
 683                 }
 684
 685                 ret = do_unmap_fn(cmd, priv, lba, range);
 686                 if (ret)
 687                         goto err;
 688
 689                 ptr += 16;
 690                 size -= 16;
 691         }
 692
 693 err:
 694         transport_kunmap_data_sg(cmd);
 695         if (!ret)
 696                 target_complete_cmd(cmd, GOOD);
 697         return ret;
 698 }
 699 EXPORT_SYMBOL(sbc_execute_unmap);