drivers/target/target_core_sbc.c

   1 /*
   2  * SCSI Block Commands (SBC) parsing and emulation.
   3  *
   4  * Copyright (c) 2002, 2003, 2004, 2005 PyX Technologies, Inc.
   5  * Copyright (c) 2005, 2006, 2007 SBE, Inc.
   6  * Copyright (c) 2007-2010 Rising Tide Systems
   7  * Copyright (c) 2008-2010 Linux-iSCSI.org
   8  *
   9  * Nicholas A. Bellinger <nab@kernel.org>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  24  */
  25
  26 #include <linux/kernel.h>
  27 #include <linux/module.h>
  28 #include <linux/ratelimit.h>
  29 #include <asm/unaligned.h>
  30 #include <scsi/scsi.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
  39
  40 static int sbc_emulate_readcapacity(struct se_cmd *cmd)
  41 {
  42         struct se_device *dev = cmd->se_dev;
  43         unsigned char *buf;
  44         unsigned long long blocks_long = dev->transport->get_blocks(dev);
  45         u32 blocks;
  46
  47         if (blocks_long >= 0x00000000ffffffff)
  48                 blocks = 0xffffffff;
  49         else
  50                 blocks = (u32)blocks_long;
  51
  52         buf = transport_kmap_data_sg(cmd);
  53
  54         buf[0] = (blocks >> 24) & 0xff;
  55         buf[1] = (blocks >> 16) & 0xff;
  56         buf[2] = (blocks >> 8) & 0xff;
  57         buf[3] = blocks & 0xff;
  58         buf[4] = (dev->se_sub_dev->se_dev_attrib.block_size >> 24) & 0xff;
  59         buf[5] = (dev->se_sub_dev->se_dev_attrib.block_size >> 16) & 0xff;
  60         buf[6] = (dev->se_sub_dev->se_dev_attrib.block_size >> 8) & 0xff;
  61         buf[7] = dev->se_sub_dev->se_dev_attrib.block_size & 0xff;
  62
  63         transport_kunmap_data_sg(cmd);
  64
  65         target_complete_cmd(cmd, GOOD);
  66         return 0;
  67 }
  68
  69 static int sbc_emulate_readcapacity_16(struct se_cmd *cmd)
  70 {
  71         struct se_device *dev = cmd->se_dev;
  72         unsigned char *buf;
  73         unsigned long long blocks = dev->transport->get_blocks(dev);
  74
  75         buf = transport_kmap_data_sg(cmd);
  76
  77         buf[0] = (blocks >> 56) & 0xff;
  78         buf[1] = (blocks >> 48) & 0xff;
  79         buf[2] = (blocks >> 40) & 0xff;
  80         buf[3] = (blocks >> 32) & 0xff;
  81         buf[4] = (blocks >> 24) & 0xff;
  82         buf[5] = (blocks >> 16) & 0xff;
  83         buf[6] = (blocks >> 8) & 0xff;
  84         buf[7] = blocks & 0xff;
  85         buf[8] = (dev->se_sub_dev->se_dev_attrib.block_size >> 24) & 0xff;
  86         buf[9] = (dev->se_sub_dev->se_dev_attrib.block_size >> 16) & 0xff;
  87         buf[10] = (dev->se_sub_dev->se_dev_attrib.block_size >> 8) & 0xff;
  88         buf[11] = dev->se_sub_dev->se_dev_attrib.block_size & 0xff;
  89         /*
  90          * Set Thin Provisioning Enable bit following sbc3r22 in section
  91          * READ CAPACITY (16) byte 14 if emulate_tpu or emulate_tpws is enabled.
  92          */
  93         if (dev->se_sub_dev->se_dev_attrib.emulate_tpu || dev->se_sub_dev->se_dev_attrib.emulate_tpws)
  94                 buf[14] = 0x80;
  95
  96         transport_kunmap_data_sg(cmd);
  97
  98         target_complete_cmd(cmd, GOOD);
  99         return 0;
 100 }
 101
 102 int spc_get_write_same_sectors(struct se_cmd *cmd)
 103 {
 104         u32 num_blocks;
 105
 106         if (cmd->t_task_cdb[0] == WRITE_SAME)
 107                 num_blocks = get_unaligned_be16(&cmd->t_task_cdb[7]);
 108         else if (cmd->t_task_cdb[0] == WRITE_SAME_16)
 109                 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[10]);
 110         else /* WRITE_SAME_32 via VARIABLE_LENGTH_CMD */
 111                 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[28]);
 112
 113         /*
 114          * Use the explicit range when non zero is supplied, otherwise calculate
 115          * the remaining range based on ->get_blocks() - starting LBA.
 116          */
 117         if (num_blocks)
 118                 return num_blocks;
 119
 120         return cmd->se_dev->transport->get_blocks(cmd->se_dev) -
 121                 cmd->t_task_lba + 1;
 122 }
 123 EXPORT_SYMBOL(spc_get_write_same_sectors);
 124
 125 static int sbc_emulate_verify(struct se_cmd *cmd)
 126 {
 127         target_complete_cmd(cmd, GOOD);
 128         return 0;
 129 }
 130
 131 static inline u32 sbc_get_size(struct se_cmd *cmd, u32 sectors)
 132 {
 133         return cmd->se_dev->se_sub_dev->se_dev_attrib.block_size * sectors;
 134 }
 135
 136 static int sbc_check_valid_sectors(struct se_cmd *cmd)
 137 {
 138         struct se_device *dev = cmd->se_dev;
 139         unsigned long long end_lba;
 140         u32 sectors;
 141
 142         sectors = cmd->data_length / dev->se_sub_dev->se_dev_attrib.block_size;
 143         end_lba = dev->transport->get_blocks(dev) + 1;
 144
 145         if (cmd->t_task_lba + sectors > end_lba) {
 146                 pr_err("target: lba %llu, sectors %u exceeds end lba %llu\n",
 147                         cmd->t_task_lba, sectors, end_lba);
 148                 return -EINVAL;
 149         }
 150
 151         return 0;
 152 }
 153
 154 static inline u32 transport_get_sectors_6(unsigned char *cdb)
 155 {
 156         /*
 157          * Use 8-bit sector value.  SBC-3 says:
 158          *
 159          *   A TRANSFER LENGTH field set to zero specifies that 256
 160          *   logical blocks shall be written.  Any other value
 161          *   specifies the number of logical blocks that shall be
 162          *   written.
 163          */
 164         return cdb[4] ? : 256;
 165 }
 166
 167 static inline u32 transport_get_sectors_10(unsigned char *cdb)
 168 {
 169         return (u32)(cdb[7] << 8) + cdb[8];
 170 }
 171
 172 static inline u32 transport_get_sectors_12(unsigned char *cdb)
 173 {
 174         return (u32)(cdb[6] << 24) + (cdb[7] << 16) + (cdb[8] << 8) + cdb[9];
 175 }
 176
 177 static inline u32 transport_get_sectors_16(unsigned char *cdb)
 178 {
 179         return (u32)(cdb[10] << 24) + (cdb[11] << 16) +
 180                     (cdb[12] << 8) + cdb[13];
 181 }
 182
 183 /*
 184  * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
 185  */
 186 static inline u32 transport_get_sectors_32(unsigned char *cdb)
 187 {
 188         return (u32)(cdb[28] << 24) + (cdb[29] << 16) +
 189                     (cdb[30] << 8) + cdb[31];
 190
 191 }
 192
 193 static inline u32 transport_lba_21(unsigned char *cdb)
 194 {
 195         return ((cdb[1] & 0x1f) << 16) | (cdb[2] << 8) | cdb[3];
 196 }
 197
 198 static inline u32 transport_lba_32(unsigned char *cdb)
 199 {
 200         return (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
 201 }
 202
 203 static inline unsigned long long transport_lba_64(unsigned char *cdb)
 204 {
 205         unsigned int __v1, __v2;
 206
 207         __v1 = (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
 208         __v2 = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
 209
 210         return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
 211 }
 212
 213 /*
 214  * For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs
 215  */
 216 static inline unsigned long long transport_lba_64_ext(unsigned char *cdb)
 217 {
 218         unsigned int __v1, __v2;
 219
 220         __v1 = (cdb[12] << 24) | (cdb[13] << 16) | (cdb[14] << 8) | cdb[15];
 221         __v2 = (cdb[16] << 24) | (cdb[17] << 16) | (cdb[18] << 8) | cdb[19];
 222
 223         return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
 224 }
 225
 226 static int sbc_write_same_supported(struct se_device *dev,
 227                 unsigned char *flags)
 228 {
 229         if ((flags[0] & 0x04) || (flags[0] & 0x02)) {
 230                 pr_err("WRITE_SAME PBDATA and LBDATA"
 231                         " bits not supported for Block Discard"
 232                         " Emulation\n");
 233                 return -ENOSYS;
 234         }
 235
 236         /*
 237          * Currently for the emulated case we only accept
 238          * tpws with the UNMAP=1 bit set.
 239          */
 240         if (!(flags[0] & 0x08)) {
 241                 pr_err("WRITE_SAME w/o UNMAP bit not"
 242                         " supported for Block Discard Emulation\n");
 243                 return -ENOSYS;
 244         }
 245
 246         return 0;
 247 }
 248
 249 static void xdreadwrite_callback(struct se_cmd *cmd)
 250 {
 251         unsigned char *buf, *addr;
 252         struct scatterlist *sg;
 253         unsigned int offset;
 254         int i;
 255         int count;
 256         /*
 257          * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
 258          *
 259          * 1) read the specified logical block(s);
 260          * 2) transfer logical blocks from the data-out buffer;
 261          * 3) XOR the logical blocks transferred from the data-out buffer with
 262          *    the logical blocks read, storing the resulting XOR data in a buffer;
 263          * 4) if the DISABLE WRITE bit is set to zero, then write the logical
 264          *    blocks transferred from the data-out buffer; and
 265          * 5) transfer the resulting XOR data to the data-in buffer.
 266          */
 267         buf = kmalloc(cmd->data_length, GFP_KERNEL);
 268         if (!buf) {
 269                 pr_err("Unable to allocate xor_callback buf\n");
 270                 return;
 271         }
 272         /*
 273          * Copy the scatterlist WRITE buffer located at cmd->t_data_sg
 274          * into the locally allocated *buf
 275          */
 276         sg_copy_to_buffer(cmd->t_data_sg,
 277                           cmd->t_data_nents,
 278                           buf,
 279                           cmd->data_length);
 280
 281         /*
 282          * Now perform the XOR against the BIDI read memory located at
 283          * cmd->t_mem_bidi_list
 284          */
 285
 286         offset = 0;
 287         for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
 288                 addr = kmap_atomic(sg_page(sg));
 289                 if (!addr)
 290                         goto out;
 291
 292                 for (i = 0; i < sg->length; i++)
 293                         *(addr + sg->offset + i) ^= *(buf + offset + i);
 294
 295                 offset += sg->length;
 296                 kunmap_atomic(addr);
 297         }
 298
 299 out:
 300         kfree(buf);
 301 }
 302
 303 int sbc_parse_cdb(struct se_cmd *cmd, struct spc_ops *ops)
 304 {
 305         struct se_subsystem_dev *su_dev = cmd->se_dev->se_sub_dev;
 306         struct se_device *dev = cmd->se_dev;
 307         unsigned char *cdb = cmd->t_task_cdb;
 308         unsigned int size;
 309         u32 sectors = 0;
 310         int ret;
 311
 312         switch (cdb[0]) {
 313         case READ_6:
 314                 sectors = transport_get_sectors_6(cdb);
 315                 cmd->t_task_lba = transport_lba_21(cdb);
 316                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 317                 cmd->execute_cmd = ops->execute_rw;
 318                 break;
 319         case READ_10:
 320                 sectors = transport_get_sectors_10(cdb);
 321                 cmd->t_task_lba = transport_lba_32(cdb);
 322                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 323                 cmd->execute_cmd = ops->execute_rw;
 324                 break;
 325         case READ_12:
 326                 sectors = transport_get_sectors_12(cdb);
 327                 cmd->t_task_lba = transport_lba_32(cdb);
 328                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 329                 cmd->execute_cmd = ops->execute_rw;
 330                 break;
 331         case READ_16:
 332                 sectors = transport_get_sectors_16(cdb);
 333                 cmd->t_task_lba = transport_lba_64(cdb);
 334                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 335                 cmd->execute_cmd = ops->execute_rw;
 336                 break;
 337         case WRITE_6:
 338                 sectors = transport_get_sectors_6(cdb);
 339                 cmd->t_task_lba = transport_lba_21(cdb);
 340                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 341                 cmd->execute_cmd = ops->execute_rw;
 342                 break;
 343         case WRITE_10:
 344         case WRITE_VERIFY:
 345                 sectors = transport_get_sectors_10(cdb);
 346                 cmd->t_task_lba = transport_lba_32(cdb);
 347                 if (cdb[1] & 0x8)
 348                         cmd->se_cmd_flags |= SCF_FUA;
 349                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 350                 cmd->execute_cmd = ops->execute_rw;
 351                 break;
 352         case WRITE_12:
 353                 sectors = transport_get_sectors_12(cdb);
 354                 cmd->t_task_lba = transport_lba_32(cdb);
 355                 if (cdb[1] & 0x8)
 356                         cmd->se_cmd_flags |= SCF_FUA;
 357                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 358                 cmd->execute_cmd = ops->execute_rw;
 359                 break;
 360         case WRITE_16:
 361                 sectors = transport_get_sectors_16(cdb);
 362                 cmd->t_task_lba = transport_lba_64(cdb);
 363                 if (cdb[1] & 0x8)
 364                         cmd->se_cmd_flags |= SCF_FUA;
 365                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 366                 cmd->execute_cmd = ops->execute_rw;
 367                 break;
 368         case XDWRITEREAD_10:
 369                 if ((cmd->data_direction != DMA_TO_DEVICE) ||
 370                     !(cmd->se_cmd_flags & SCF_BIDI))
 371                         goto out_invalid_cdb_field;
 372                 sectors = transport_get_sectors_10(cdb);
 373
 374                 cmd->t_task_lba = transport_lba_32(cdb);
 375                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 376
 377                 /*
 378                  * Setup BIDI XOR callback to be run after I/O completion.
 379                  */
 380                 cmd->execute_cmd = ops->execute_rw;
 381                 cmd->transport_complete_callback = &xdreadwrite_callback;
 382                 if (cdb[1] & 0x8)
 383                         cmd->se_cmd_flags |= SCF_FUA;
 384                 break;
 385         case VARIABLE_LENGTH_CMD:
 386         {
 387                 u16 service_action = get_unaligned_be16(&cdb[8]);
 388                 switch (service_action) {
 389                 case XDWRITEREAD_32:
 390                         sectors = transport_get_sectors_32(cdb);
 391
 392                         /*
 393                          * Use WRITE_32 and READ_32 opcodes for the emulated
 394                          * XDWRITE_READ_32 logic.
 395                          */
 396                         cmd->t_task_lba = transport_lba_64_ext(cdb);
 397                         cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 398
 399                         /*
 400                          * Setup BIDI XOR callback to be run during after I/O
 401                          * completion.
 402                          */
 403                         cmd->execute_cmd = ops->execute_rw;
 404                         cmd->transport_complete_callback = &xdreadwrite_callback;
 405                         if (cdb[1] & 0x8)
 406                                 cmd->se_cmd_flags |= SCF_FUA;
 407                         break;
 408                 case WRITE_SAME_32:
 409                         if (!ops->execute_write_same)
 410                                 goto out_unsupported_cdb;
 411
 412                         sectors = transport_get_sectors_32(cdb);
 413                         if (!sectors) {
 414                                 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
 415                                        " supported\n");
 416                                 goto out_invalid_cdb_field;
 417                         }
 418
 419                         size = sbc_get_size(cmd, 1);
 420                         cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
 421
 422                         if (sbc_write_same_supported(dev, &cdb[10]) < 0)
 423                                 goto out_unsupported_cdb;
 424                         cmd->execute_cmd = ops->execute_write_same;
 425                         break;
 426                 default:
 427                         pr_err("VARIABLE_LENGTH_CMD service action"
 428                                 " 0x%04x not supported\n", service_action);
 429                         goto out_unsupported_cdb;
 430                 }
 431                 break;
 432         }
 433         case READ_CAPACITY:
 434                 size = READ_CAP_LEN;
 435                 cmd->execute_cmd = sbc_emulate_readcapacity;
 436                 break;
 437         case SERVICE_ACTION_IN:
 438                 switch (cmd->t_task_cdb[1] & 0x1f) {
 439                 case SAI_READ_CAPACITY_16:
 440                         cmd->execute_cmd = sbc_emulate_readcapacity_16;
 441                         break;
 442                 default:
 443                         pr_err("Unsupported SA: 0x%02x\n",
 444                                 cmd->t_task_cdb[1] & 0x1f);
 445                         goto out_invalid_cdb_field;
 446                 }
 447                 size = (cdb[10] << 24) | (cdb[11] << 16) |
 448                        (cdb[12] << 8) | cdb[13];
 449                 break;
 450         case SYNCHRONIZE_CACHE:
 451         case SYNCHRONIZE_CACHE_16:
 452                 if (!ops->execute_sync_cache)
 453                         goto out_unsupported_cdb;
 454
 455                 /*
 456                  * Extract LBA and range to be flushed for emulated SYNCHRONIZE_CACHE
 457                  */
 458                 if (cdb[0] == SYNCHRONIZE_CACHE) {
 459                         sectors = transport_get_sectors_10(cdb);
 460                         cmd->t_task_lba = transport_lba_32(cdb);
 461                 } else {
 462                         sectors = transport_get_sectors_16(cdb);
 463                         cmd->t_task_lba = transport_lba_64(cdb);
 464                 }
 465
 466                 size = sbc_get_size(cmd, sectors);
 467
 468                 /*
 469                  * Check to ensure that LBA + Range does not exceed past end of
 470                  * device for IBLOCK and FILEIO ->do_sync_cache() backend calls
 471                  */
 472                 if (cmd->t_task_lba || sectors) {
 473                         if (sbc_check_valid_sectors(cmd) < 0)
 474                                 goto out_invalid_cdb_field;
 475                 }
 476                 cmd->execute_cmd = ops->execute_sync_cache;
 477                 break;
 478         case UNMAP:
 479                 if (!ops->execute_unmap)
 480                         goto out_unsupported_cdb;
 481
 482                 size = get_unaligned_be16(&cdb[7]);
 483                 cmd->execute_cmd = ops->execute_unmap;
 484                 break;
 485         case WRITE_SAME_16:
 486                 if (!ops->execute_write_same)
 487                         goto out_unsupported_cdb;
 488
 489                 sectors = transport_get_sectors_16(cdb);
 490                 if (!sectors) {
 491                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
 492                         goto out_invalid_cdb_field;
 493                 }
 494
 495                 size = sbc_get_size(cmd, 1);
 496                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
 497
 498                 if (sbc_write_same_supported(dev, &cdb[1]) < 0)
 499                         goto out_unsupported_cdb;
 500                 cmd->execute_cmd = ops->execute_write_same;
 501                 break;
 502         case WRITE_SAME:
 503                 if (!ops->execute_write_same)
 504                         goto out_unsupported_cdb;
 505
 506                 sectors = transport_get_sectors_10(cdb);
 507                 if (!sectors) {
 508                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
 509                         goto out_invalid_cdb_field;
 510                 }
 511
 512                 size = sbc_get_size(cmd, 1);
 513                 cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
 514
 515                 /*
 516                  * Follow sbcr26 with WRITE_SAME (10) and check for the existence
 517                  * of byte 1 bit 3 UNMAP instead of original reserved field
 518                  */
 519                 if (sbc_write_same_supported(dev, &cdb[1]) < 0)
 520                         goto out_unsupported_cdb;
 521                 cmd->execute_cmd = ops->execute_write_same;
 522                 break;
 523         case VERIFY:
 524                 size = 0;
 525                 cmd->execute_cmd = sbc_emulate_verify;
 526                 break;
 527         default:
 528                 ret = spc_parse_cdb(cmd, &size);
 529                 if (ret)
 530                         return ret;
 531         }
 532
 533         /* reject any command that we don't have a handler for */
 534         if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) && !cmd->execute_cmd)
 535                 goto out_unsupported_cdb;
 536
 537         if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
 538                 unsigned long long end_lba;
 539
 540                 if (sectors > su_dev->se_dev_attrib.fabric_max_sectors) {
 541                         printk_ratelimited(KERN_ERR "SCSI OP %02xh with too"
 542                                 " big sectors %u exceeds fabric_max_sectors:"
 543                                 " %u\n", cdb[0], sectors,
 544                                 su_dev->se_dev_attrib.fabric_max_sectors);
 545                         goto out_invalid_cdb_field;
 546                 }
 547                 if (sectors > su_dev->se_dev_attrib.hw_max_sectors) {
 548                         printk_ratelimited(KERN_ERR "SCSI OP %02xh with too"
 549                                 " big sectors %u exceeds backend hw_max_sectors:"
 550                                 " %u\n", cdb[0], sectors,
 551                                 su_dev->se_dev_attrib.hw_max_sectors);
 552                         goto out_invalid_cdb_field;
 553                 }
 554
 555                 end_lba = dev->transport->get_blocks(dev) + 1;
 556                 if (cmd->t_task_lba + sectors > end_lba) {
 557                         pr_err("cmd exceeds last lba %llu "
 558                                 "(lba %llu, sectors %u)\n",
 559                                 end_lba, cmd->t_task_lba, sectors);
 560                         goto out_invalid_cdb_field;
 561                 }
 562
 563                 size = sbc_get_size(cmd, sectors);
 564         }
 565
 566         ret = target_cmd_size_check(cmd, size);
 567         if (ret < 0)
 568                 return ret;
 569
 570         return 0;
 571
 572 out_unsupported_cdb:
 573         cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
 574         cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
 575         return -EINVAL;
 576 out_invalid_cdb_field:
 577         cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
 578         cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
 579         return -EINVAL;
 580 }
 581 EXPORT_SYMBOL(sbc_parse_cdb);