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 <asm/unaligned.h>
  28 #include <scsi/scsi_proto.h>
  29 #include <scsi/scsi_tcq.h>
  30
  31 #include <target/target_core_base.h>
  32 #include <target/target_core_backend.h>
  33 #include <target/target_core_fabric.h>
  34
  35 #include "target_core_internal.h"
  36 #include "target_core_ua.h"
  37 #include "target_core_alua.h"
  38
  39 static sense_reason_t
  40 sbc_check_prot(struct se_device *, struct se_cmd *, unsigned char *, u32, bool);
  41 static sense_reason_t sbc_execute_unmap(struct se_cmd *cmd);
  42
  43 static sense_reason_t
  44 sbc_emulate_readcapacity(struct se_cmd *cmd)
  45 {
  46         struct se_device *dev = cmd->se_dev;
  47         unsigned char *cdb = cmd->t_task_cdb;
  48         unsigned long long blocks_long = dev->transport->get_blocks(dev);
  49         unsigned char *rbuf;
  50         unsigned char buf[8];
  51         u32 blocks;
  52
  53         /*
  54          * SBC-2 says:
  55          *   If the PMI bit is set to zero and the LOGICAL BLOCK
  56          *   ADDRESS field is not set to zero, the device server shall
  57          *   terminate the command with CHECK CONDITION status with
  58          *   the sense key set to ILLEGAL REQUEST and the additional
  59          *   sense code set to INVALID FIELD IN CDB.
  60          *
  61          * In SBC-3, these fields are obsolete, but some SCSI
  62          * compliance tests actually check this, so we might as well
  63          * follow SBC-2.
  64          */
  65         if (!(cdb[8] & 1) && !!(cdb[2] | cdb[3] | cdb[4] | cdb[5]))
  66                 return TCM_INVALID_CDB_FIELD;
  67
  68         if (blocks_long >= 0x00000000ffffffff)
  69                 blocks = 0xffffffff;
  70         else
  71                 blocks = (u32)blocks_long;
  72
  73         buf[0] = (blocks >> 24) & 0xff;
  74         buf[1] = (blocks >> 16) & 0xff;
  75         buf[2] = (blocks >> 8) & 0xff;
  76         buf[3] = blocks & 0xff;
  77         buf[4] = (dev->dev_attrib.block_size >> 24) & 0xff;
  78         buf[5] = (dev->dev_attrib.block_size >> 16) & 0xff;
  79         buf[6] = (dev->dev_attrib.block_size >> 8) & 0xff;
  80         buf[7] = dev->dev_attrib.block_size & 0xff;
  81
  82         rbuf = transport_kmap_data_sg(cmd);
  83         if (rbuf) {
  84                 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
  85                 transport_kunmap_data_sg(cmd);
  86         }
  87
  88         target_complete_cmd_with_length(cmd, GOOD, 8);
  89         return 0;
  90 }
  91
  92 static sense_reason_t
  93 sbc_emulate_readcapacity_16(struct se_cmd *cmd)
  94 {
  95         struct se_device *dev = cmd->se_dev;
  96         struct se_session *sess = cmd->se_sess;
  97         int pi_prot_type = dev->dev_attrib.pi_prot_type;
  98
  99         unsigned char *rbuf;
 100         unsigned char buf[32];
 101         unsigned long long blocks = dev->transport->get_blocks(dev);
 102
 103         memset(buf, 0, sizeof(buf));
 104         buf[0] = (blocks >> 56) & 0xff;
 105         buf[1] = (blocks >> 48) & 0xff;
 106         buf[2] = (blocks >> 40) & 0xff;
 107         buf[3] = (blocks >> 32) & 0xff;
 108         buf[4] = (blocks >> 24) & 0xff;
 109         buf[5] = (blocks >> 16) & 0xff;
 110         buf[6] = (blocks >> 8) & 0xff;
 111         buf[7] = blocks & 0xff;
 112         buf[8] = (dev->dev_attrib.block_size >> 24) & 0xff;
 113         buf[9] = (dev->dev_attrib.block_size >> 16) & 0xff;
 114         buf[10] = (dev->dev_attrib.block_size >> 8) & 0xff;
 115         buf[11] = dev->dev_attrib.block_size & 0xff;
 116         /*
 117          * Set P_TYPE and PROT_EN bits for DIF support
 118          */
 119         if (sess->sup_prot_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS)) {
 120                 /*
 121                  * Only override a device's pi_prot_type if no T10-PI is
 122                  * available, and sess_prot_type has been explicitly enabled.
 123                  */
 124                 if (!pi_prot_type)
 125                         pi_prot_type = sess->sess_prot_type;
 126
 127                 if (pi_prot_type)
 128                         buf[12] = (pi_prot_type - 1) << 1 | 0x1;
 129         }
 130
 131         if (dev->transport->get_lbppbe)
 132                 buf[13] = dev->transport->get_lbppbe(dev) & 0x0f;
 133
 134         if (dev->transport->get_alignment_offset_lbas) {
 135                 u16 lalba = dev->transport->get_alignment_offset_lbas(dev);
 136                 buf[14] = (lalba >> 8) & 0x3f;
 137                 buf[15] = lalba & 0xff;
 138         }
 139
 140         /*
 141          * Set Thin Provisioning Enable bit following sbc3r22 in section
 142          * READ CAPACITY (16) byte 14 if emulate_tpu or emulate_tpws is enabled.
 143          */
 144         if (dev->dev_attrib.emulate_tpu || dev->dev_attrib.emulate_tpws)
 145                 buf[14] |= 0x80;
 146
 147         rbuf = transport_kmap_data_sg(cmd);
 148         if (rbuf) {
 149                 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
 150                 transport_kunmap_data_sg(cmd);
 151         }
 152
 153         target_complete_cmd_with_length(cmd, GOOD, 32);
 154         return 0;
 155 }
 156
 157 static sense_reason_t
 158 sbc_emulate_startstop(struct se_cmd *cmd)
 159 {
 160         unsigned char *cdb = cmd->t_task_cdb;
 161
 162         /*
 163          * See sbc3r36 section 5.25
 164          * Immediate bit should be set since there is nothing to complete
 165          * POWER CONDITION MODIFIER 0h
 166          */
 167         if (!(cdb[1] & 1) || cdb[2] || cdb[3])
 168                 return TCM_INVALID_CDB_FIELD;
 169
 170         /*
 171          * See sbc3r36 section 5.25
 172          * POWER CONDITION 0h START_VALID - process START and LOEJ
 173          */
 174         if (cdb[4] >> 4 & 0xf)
 175                 return TCM_INVALID_CDB_FIELD;
 176
 177         /*
 178          * See sbc3r36 section 5.25
 179          * LOEJ 0h - nothing to load or unload
 180          * START 1h - we are ready
 181          */
 182         if (!(cdb[4] & 1) || (cdb[4] & 2) || (cdb[4] & 4))
 183                 return TCM_INVALID_CDB_FIELD;
 184
 185         target_complete_cmd(cmd, SAM_STAT_GOOD);
 186         return 0;
 187 }
 188
 189 sector_t sbc_get_write_same_sectors(struct se_cmd *cmd)
 190 {
 191         u32 num_blocks;
 192
 193         if (cmd->t_task_cdb[0] == WRITE_SAME)
 194                 num_blocks = get_unaligned_be16(&cmd->t_task_cdb[7]);
 195         else if (cmd->t_task_cdb[0] == WRITE_SAME_16)
 196                 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[10]);
 197         else /* WRITE_SAME_32 via VARIABLE_LENGTH_CMD */
 198                 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[28]);
 199
 200         /*
 201          * Use the explicit range when non zero is supplied, otherwise calculate
 202          * the remaining range based on ->get_blocks() - starting LBA.
 203          */
 204         if (num_blocks)
 205                 return num_blocks;
 206
 207         return cmd->se_dev->transport->get_blocks(cmd->se_dev) -
 208                 cmd->t_task_lba + 1;
 209 }
 210 EXPORT_SYMBOL(sbc_get_write_same_sectors);
 211
 212 static sense_reason_t
 213 sbc_execute_write_same_unmap(struct se_cmd *cmd)
 214 {
 215         struct sbc_ops *ops = cmd->protocol_data;
 216         sector_t nolb = sbc_get_write_same_sectors(cmd);
 217         sense_reason_t ret;
 218
 219         if (nolb) {
 220                 ret = ops->execute_unmap(cmd, cmd->t_task_lba, nolb);
 221                 if (ret)
 222                         return ret;
 223         }
 224
 225         target_complete_cmd(cmd, GOOD);
 226         return 0;
 227 }
 228
 229 static sense_reason_t
 230 sbc_emulate_noop(struct se_cmd *cmd)
 231 {
 232         target_complete_cmd(cmd, GOOD);
 233         return 0;
 234 }
 235
 236 static inline u32 sbc_get_size(struct se_cmd *cmd, u32 sectors)
 237 {
 238         return cmd->se_dev->dev_attrib.block_size * sectors;
 239 }
 240
 241 static inline u32 transport_get_sectors_6(unsigned char *cdb)
 242 {
 243         /*
 244          * Use 8-bit sector value.  SBC-3 says:
 245          *
 246          *   A TRANSFER LENGTH field set to zero specifies that 256
 247          *   logical blocks shall be written.  Any other value
 248          *   specifies the number of logical blocks that shall be
 249          *   written.
 250          */
 251         return cdb[4] ? : 256;
 252 }
 253
 254 static inline u32 transport_get_sectors_10(unsigned char *cdb)
 255 {
 256         return (u32)(cdb[7] << 8) + cdb[8];
 257 }
 258
 259 static inline u32 transport_get_sectors_12(unsigned char *cdb)
 260 {
 261         return (u32)(cdb[6] << 24) + (cdb[7] << 16) + (cdb[8] << 8) + cdb[9];
 262 }
 263
 264 static inline u32 transport_get_sectors_16(unsigned char *cdb)
 265 {
 266         return (u32)(cdb[10] << 24) + (cdb[11] << 16) +
 267                     (cdb[12] << 8) + cdb[13];
 268 }
 269
 270 /*
 271  * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
 272  */
 273 static inline u32 transport_get_sectors_32(unsigned char *cdb)
 274 {
 275         return (u32)(cdb[28] << 24) + (cdb[29] << 16) +
 276                     (cdb[30] << 8) + cdb[31];
 277
 278 }
 279
 280 static inline u32 transport_lba_21(unsigned char *cdb)
 281 {
 282         return ((cdb[1] & 0x1f) << 16) | (cdb[2] << 8) | cdb[3];
 283 }
 284
 285 static inline u32 transport_lba_32(unsigned char *cdb)
 286 {
 287         return (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
 288 }
 289
 290 static inline unsigned long long transport_lba_64(unsigned char *cdb)
 291 {
 292         unsigned int __v1, __v2;
 293
 294         __v1 = (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
 295         __v2 = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
 296
 297         return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
 298 }
 299
 300 /*
 301  * For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs
 302  */
 303 static inline unsigned long long transport_lba_64_ext(unsigned char *cdb)
 304 {
 305         unsigned int __v1, __v2;
 306
 307         __v1 = (cdb[12] << 24) | (cdb[13] << 16) | (cdb[14] << 8) | cdb[15];
 308         __v2 = (cdb[16] << 24) | (cdb[17] << 16) | (cdb[18] << 8) | cdb[19];
 309
 310         return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
 311 }
 312
 313 static sense_reason_t
 314 sbc_setup_write_same(struct se_cmd *cmd, unsigned char *flags, struct sbc_ops *ops)
 315 {
 316         struct se_device *dev = cmd->se_dev;
 317         sector_t end_lba = dev->transport->get_blocks(dev) + 1;
 318         unsigned int sectors = sbc_get_write_same_sectors(cmd);
 319         sense_reason_t ret;
 320
 321         if ((flags[0] & 0x04) || (flags[0] & 0x02)) {
 322                 pr_err("WRITE_SAME PBDATA and LBDATA"
 323                         " bits not supported for Block Discard"
 324                         " Emulation\n");
 325                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 326         }
 327         if (sectors > cmd->se_dev->dev_attrib.max_write_same_len) {
 328                 pr_warn("WRITE_SAME sectors: %u exceeds max_write_same_len: %u\n",
 329                         sectors, cmd->se_dev->dev_attrib.max_write_same_len);
 330                 return TCM_INVALID_CDB_FIELD;
 331         }
 332         /*
 333          * Sanity check for LBA wrap and request past end of device.
 334          */
 335         if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
 336             ((cmd->t_task_lba + sectors) > end_lba)) {
 337                 pr_err("WRITE_SAME exceeds last lba %llu (lba %llu, sectors %u)\n",
 338                        (unsigned long long)end_lba, cmd->t_task_lba, sectors);
 339                 return TCM_ADDRESS_OUT_OF_RANGE;
 340         }
 341
 342         /* We always have ANC_SUP == 0 so setting ANCHOR is always an error */
 343         if (flags[0] & 0x10) {
 344                 pr_warn("WRITE SAME with ANCHOR not supported\n");
 345                 return TCM_INVALID_CDB_FIELD;
 346         }
 347         /*
 348          * Special case for WRITE_SAME w/ UNMAP=1 that ends up getting
 349          * translated into block discard requests within backend code.
 350          */
 351         if (flags[0] & 0x08) {
 352                 if (!ops->execute_unmap)
 353                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 354
 355                 if (!dev->dev_attrib.emulate_tpws) {
 356                         pr_err("Got WRITE_SAME w/ UNMAP=1, but backend device"
 357                                " has emulate_tpws disabled\n");
 358                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 359                 }
 360                 cmd->execute_cmd = sbc_execute_write_same_unmap;
 361                 return 0;
 362         }
 363         if (!ops->execute_write_same)
 364                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 365
 366         ret = sbc_check_prot(dev, cmd, &cmd->t_task_cdb[0], sectors, true);
 367         if (ret)
 368                 return ret;
 369
 370         cmd->execute_cmd = ops->execute_write_same;
 371         return 0;
 372 }
 373
 374 static sense_reason_t xdreadwrite_callback(struct se_cmd *cmd, bool success,
 375                                            int *post_ret)
 376 {
 377         unsigned char *buf, *addr;
 378         struct scatterlist *sg;
 379         unsigned int offset;
 380         sense_reason_t ret = TCM_NO_SENSE;
 381         int i, count;
 382         /*
 383          * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
 384          *
 385          * 1) read the specified logical block(s);
 386          * 2) transfer logical blocks from the data-out buffer;
 387          * 3) XOR the logical blocks transferred from the data-out buffer with
 388          *    the logical blocks read, storing the resulting XOR data in a buffer;
 389          * 4) if the DISABLE WRITE bit is set to zero, then write the logical
 390          *    blocks transferred from the data-out buffer; and
 391          * 5) transfer the resulting XOR data to the data-in buffer.
 392          */
 393         buf = kmalloc(cmd->data_length, GFP_KERNEL);
 394         if (!buf) {
 395                 pr_err("Unable to allocate xor_callback buf\n");
 396                 return TCM_OUT_OF_RESOURCES;
 397         }
 398         /*
 399          * Copy the scatterlist WRITE buffer located at cmd->t_data_sg
 400          * into the locally allocated *buf
 401          */
 402         sg_copy_to_buffer(cmd->t_data_sg,
 403                           cmd->t_data_nents,
 404                           buf,
 405                           cmd->data_length);
 406
 407         /*
 408          * Now perform the XOR against the BIDI read memory located at
 409          * cmd->t_mem_bidi_list
 410          */
 411
 412         offset = 0;
 413         for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
 414                 addr = kmap_atomic(sg_page(sg));
 415                 if (!addr) {
 416                         ret = TCM_OUT_OF_RESOURCES;
 417                         goto out;
 418                 }
 419
 420                 for (i = 0; i < sg->length; i++)
 421                         *(addr + sg->offset + i) ^= *(buf + offset + i);
 422
 423                 offset += sg->length;
 424                 kunmap_atomic(addr);
 425         }
 426
 427 out:
 428         kfree(buf);
 429         return ret;
 430 }
 431
 432 static sense_reason_t
 433 sbc_execute_rw(struct se_cmd *cmd)
 434 {
 435         struct sbc_ops *ops = cmd->protocol_data;
 436
 437         return ops->execute_rw(cmd, cmd->t_data_sg, cmd->t_data_nents,
 438                                cmd->data_direction);
 439 }
 440
 441 static sense_reason_t compare_and_write_post(struct se_cmd *cmd, bool success,
 442                                              int *post_ret)
 443 {
 444         struct se_device *dev = cmd->se_dev;
 445         sense_reason_t ret = TCM_NO_SENSE;
 446
 447         /*
 448          * Only set SCF_COMPARE_AND_WRITE_POST to force a response fall-through
 449          * within target_complete_ok_work() if the command was successfully
 450          * sent to the backend driver.
 451          */
 452         spin_lock_irq(&cmd->t_state_lock);
 453         if (cmd->transport_state & CMD_T_SENT) {
 454                 cmd->se_cmd_flags |= SCF_COMPARE_AND_WRITE_POST;
 455                 *post_ret = 1;
 456
 457                 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION)
 458                         ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 459         }
 460         spin_unlock_irq(&cmd->t_state_lock);
 461
 462         /*
 463          * Unlock ->caw_sem originally obtained during sbc_compare_and_write()
 464          * before the original READ I/O submission.
 465          */
 466         up(&dev->caw_sem);
 467
 468         return ret;
 469 }
 470
 471 static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool success,
 472                                                  int *post_ret)
 473 {
 474         struct se_device *dev = cmd->se_dev;
 475         struct scatterlist *write_sg = NULL, *sg;
 476         unsigned char *buf = NULL, *addr;
 477         struct sg_mapping_iter m;
 478         unsigned int offset = 0, len;
 479         unsigned int nlbas = cmd->t_task_nolb;
 480         unsigned int block_size = dev->dev_attrib.block_size;
 481         unsigned int compare_len = (nlbas * block_size);
 482         sense_reason_t ret = TCM_NO_SENSE;
 483         int rc, i;
 484
 485         /*
 486          * Handle early failure in transport_generic_request_failure(),
 487          * which will not have taken ->caw_sem yet..
 488          */
 489         if (!success && (!cmd->t_data_sg || !cmd->t_bidi_data_sg))
 490                 return TCM_NO_SENSE;
 491         /*
 492          * Handle special case for zero-length COMPARE_AND_WRITE
 493          */
 494         if (!cmd->data_length)
 495                 goto out;
 496         /*
 497          * Immediately exit + release dev->caw_sem if command has already
 498          * been failed with a non-zero SCSI status.
 499          */
 500         if (cmd->scsi_status) {
 501                 pr_err("compare_and_write_callback: non zero scsi_status:"
 502                         " 0x%02x\n", cmd->scsi_status);
 503                 goto out;
 504         }
 505
 506         buf = kzalloc(cmd->data_length, GFP_KERNEL);
 507         if (!buf) {
 508                 pr_err("Unable to allocate compare_and_write buf\n");
 509                 ret = TCM_OUT_OF_RESOURCES;
 510                 goto out;
 511         }
 512
 513         write_sg = kmalloc(sizeof(struct scatterlist) * cmd->t_data_nents,
 514                            GFP_KERNEL);
 515         if (!write_sg) {
 516                 pr_err("Unable to allocate compare_and_write sg\n");
 517                 ret = TCM_OUT_OF_RESOURCES;
 518                 goto out;
 519         }
 520         sg_init_table(write_sg, cmd->t_data_nents);
 521         /*
 522          * Setup verify and write data payloads from total NumberLBAs.
 523          */
 524         rc = sg_copy_to_buffer(cmd->t_data_sg, cmd->t_data_nents, buf,
 525                                cmd->data_length);
 526         if (!rc) {
 527                 pr_err("sg_copy_to_buffer() failed for compare_and_write\n");
 528                 ret = TCM_OUT_OF_RESOURCES;
 529                 goto out;
 530         }
 531         /*
 532          * Compare against SCSI READ payload against verify payload
 533          */
 534         for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, i) {
 535                 addr = (unsigned char *)kmap_atomic(sg_page(sg));
 536                 if (!addr) {
 537                         ret = TCM_OUT_OF_RESOURCES;
 538                         goto out;
 539                 }
 540
 541                 len = min(sg->length, compare_len);
 542
 543                 if (memcmp(addr, buf + offset, len)) {
 544                         pr_warn("Detected MISCOMPARE for addr: %p buf: %p\n",
 545                                 addr, buf + offset);
 546                         kunmap_atomic(addr);
 547                         goto miscompare;
 548                 }
 549                 kunmap_atomic(addr);
 550
 551                 offset += len;
 552                 compare_len -= len;
 553                 if (!compare_len)
 554                         break;
 555         }
 556
 557         i = 0;
 558         len = cmd->t_task_nolb * block_size;
 559         sg_miter_start(&m, cmd->t_data_sg, cmd->t_data_nents, SG_MITER_TO_SG);
 560         /*
 561          * Currently assumes NoLB=1 and SGLs are PAGE_SIZE..
 562          */
 563         while (len) {
 564                 sg_miter_next(&m);
 565
 566                 if (block_size < PAGE_SIZE) {
 567                         sg_set_page(&write_sg[i], m.page, block_size,
 568                                     m.piter.sg->offset + block_size);
 569                 } else {
 570                         sg_miter_next(&m);
 571                         sg_set_page(&write_sg[i], m.page, block_size,
 572                                     m.piter.sg->offset);
 573                 }
 574                 len -= block_size;
 575                 i++;
 576         }
 577         sg_miter_stop(&m);
 578         /*
 579          * Save the original SGL + nents values before updating to new
 580          * assignments, to be released in transport_free_pages() ->
 581          * transport_reset_sgl_orig()
 582          */
 583         cmd->t_data_sg_orig = cmd->t_data_sg;
 584         cmd->t_data_sg = write_sg;
 585         cmd->t_data_nents_orig = cmd->t_data_nents;
 586         cmd->t_data_nents = 1;
 587
 588         cmd->sam_task_attr = TCM_HEAD_TAG;
 589         cmd->transport_complete_callback = compare_and_write_post;
 590         /*
 591          * Now reset ->execute_cmd() to the normal sbc_execute_rw() handler
 592          * for submitting the adjusted SGL to write instance user-data.
 593          */
 594         cmd->execute_cmd = sbc_execute_rw;
 595
 596         spin_lock_irq(&cmd->t_state_lock);
 597         cmd->t_state = TRANSPORT_PROCESSING;
 598         cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
 599         spin_unlock_irq(&cmd->t_state_lock);
 600
 601         __target_execute_cmd(cmd, false);
 602
 603         kfree(buf);
 604         return ret;
 605
 606 miscompare:
 607         pr_warn("Target/%s: Send MISCOMPARE check condition and sense\n",
 608                 dev->transport->name);
 609         ret = TCM_MISCOMPARE_VERIFY;
 610 out:
 611         /*
 612          * In the MISCOMPARE or failure case, unlock ->caw_sem obtained in
 613          * sbc_compare_and_write() before the original READ I/O submission.
 614          */
 615         up(&dev->caw_sem);
 616         kfree(write_sg);
 617         kfree(buf);
 618         return ret;
 619 }
 620
 621 static sense_reason_t
 622 sbc_compare_and_write(struct se_cmd *cmd)
 623 {
 624         struct sbc_ops *ops = cmd->protocol_data;
 625         struct se_device *dev = cmd->se_dev;
 626         sense_reason_t ret;
 627         int rc;
 628         /*
 629          * Submit the READ first for COMPARE_AND_WRITE to perform the
 630          * comparision using SGLs at cmd->t_bidi_data_sg..
 631          */
 632         rc = down_interruptible(&dev->caw_sem);
 633         if (rc != 0) {
 634                 cmd->transport_complete_callback = NULL;
 635                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 636         }
 637         /*
 638          * Reset cmd->data_length to individual block_size in order to not
 639          * confuse backend drivers that depend on this value matching the
 640          * size of the I/O being submitted.
 641          */
 642         cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size;
 643
 644         ret = ops->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents,
 645                               DMA_FROM_DEVICE);
 646         if (ret) {
 647                 cmd->transport_complete_callback = NULL;
 648                 up(&dev->caw_sem);
 649                 return ret;
 650         }
 651         /*
 652          * Unlock of dev->caw_sem to occur in compare_and_write_callback()
 653          * upon MISCOMPARE, or in compare_and_write_done() upon completion
 654          * of WRITE instance user-data.
 655          */
 656         return TCM_NO_SENSE;
 657 }
 658
 659 static int
 660 sbc_set_prot_op_checks(u8 protect, bool fabric_prot, enum target_prot_type prot_type,
 661                        bool is_write, struct se_cmd *cmd)
 662 {
 663         if (is_write) {
 664                 cmd->prot_op = fabric_prot ? TARGET_PROT_DOUT_STRIP :
 665                                protect ? TARGET_PROT_DOUT_PASS :
 666                                TARGET_PROT_DOUT_INSERT;
 667                 switch (protect) {
 668                 case 0x0:
 669                 case 0x3:
 670                         cmd->prot_checks = 0;
 671                         break;
 672                 case 0x1:
 673                 case 0x5:
 674                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 675                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 676                                 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 677                         break;
 678                 case 0x2:
 679                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 680                                 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 681                         break;
 682                 case 0x4:
 683                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 684                         break;
 685                 default:
 686                         pr_err("Unsupported protect field %d\n", protect);
 687                         return -EINVAL;
 688                 }
 689         } else {
 690                 cmd->prot_op = fabric_prot ? TARGET_PROT_DIN_INSERT :
 691                                protect ? TARGET_PROT_DIN_PASS :
 692                                TARGET_PROT_DIN_STRIP;
 693                 switch (protect) {
 694                 case 0x0:
 695                 case 0x1:
 696                 case 0x5:
 697                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 698                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 699                                 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 700                         break;
 701                 case 0x2:
 702                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 703                                 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 704                         break;
 705                 case 0x3:
 706                         cmd->prot_checks = 0;
 707                         break;
 708                 case 0x4:
 709                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 710                         break;
 711                 default:
 712                         pr_err("Unsupported protect field %d\n", protect);
 713                         return -EINVAL;
 714                 }
 715         }
 716
 717         return 0;
 718 }
 719
 720 static sense_reason_t
 721 sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb,
 722                u32 sectors, bool is_write)
 723 {
 724         u8 protect = cdb[1] >> 5;
 725         int sp_ops = cmd->se_sess->sup_prot_ops;
 726         int pi_prot_type = dev->dev_attrib.pi_prot_type;
 727         bool fabric_prot = false;
 728
 729         if (!cmd->t_prot_sg || !cmd->t_prot_nents) {
 730                 if (unlikely(protect &&
 731                     !dev->dev_attrib.pi_prot_type && !cmd->se_sess->sess_prot_type)) {
 732                         pr_err("CDB contains protect bit, but device + fabric does"
 733                                " not advertise PROTECT=1 feature bit\n");
 734                         return TCM_INVALID_CDB_FIELD;
 735                 }
 736                 if (cmd->prot_pto)
 737                         return TCM_NO_SENSE;
 738         }
 739
 740         switch (dev->dev_attrib.pi_prot_type) {
 741         case TARGET_DIF_TYPE3_PROT:
 742                 cmd->reftag_seed = 0xffffffff;
 743                 break;
 744         case TARGET_DIF_TYPE2_PROT:
 745                 if (protect)
 746                         return TCM_INVALID_CDB_FIELD;
 747
 748                 cmd->reftag_seed = cmd->t_task_lba;
 749                 break;
 750         case TARGET_DIF_TYPE1_PROT:
 751                 cmd->reftag_seed = cmd->t_task_lba;
 752                 break;
 753         case TARGET_DIF_TYPE0_PROT:
 754                 /*
 755                  * See if the fabric supports T10-PI, and the session has been
 756                  * configured to allow export PROTECT=1 feature bit with backend
 757                  * devices that don't support T10-PI.
 758                  */
 759                 fabric_prot = is_write ?
 760                               !!(sp_ops & (TARGET_PROT_DOUT_PASS | TARGET_PROT_DOUT_STRIP)) :
 761                               !!(sp_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DIN_INSERT));
 762
 763                 if (fabric_prot && cmd->se_sess->sess_prot_type) {
 764                         pi_prot_type = cmd->se_sess->sess_prot_type;
 765                         break;
 766                 }
 767                 if (!protect)
 768                         return TCM_NO_SENSE;
 769                 /* Fallthrough */
 770         default:
 771                 pr_err("Unable to determine pi_prot_type for CDB: 0x%02x "
 772                        "PROTECT: 0x%02x\n", cdb[0], protect);
 773                 return TCM_INVALID_CDB_FIELD;
 774         }
 775
 776         if (sbc_set_prot_op_checks(protect, fabric_prot, pi_prot_type, is_write, cmd))
 777                 return TCM_INVALID_CDB_FIELD;
 778
 779         cmd->prot_type = pi_prot_type;
 780         cmd->prot_length = dev->prot_length * sectors;
 781
 782         /**
 783          * In case protection information exists over the wire
 784          * we modify command data length to describe pure data.
 785          * The actual transfer length is data length + protection
 786          * length
 787          **/
 788         if (protect)
 789                 cmd->data_length = sectors * dev->dev_attrib.block_size;
 790
 791         pr_debug("%s: prot_type=%d, data_length=%d, prot_length=%d "
 792                  "prot_op=%d prot_checks=%d\n",
 793                  __func__, cmd->prot_type, cmd->data_length, cmd->prot_length,
 794                  cmd->prot_op, cmd->prot_checks);
 795
 796         return TCM_NO_SENSE;
 797 }
 798
 799 static int
 800 sbc_check_dpofua(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb)
 801 {
 802         if (cdb[1] & 0x10) {
 803                 /* see explanation in spc_emulate_modesense */
 804                 if (!target_check_fua(dev)) {
 805                         pr_err("Got CDB: 0x%02x with DPO bit set, but device"
 806                                " does not advertise support for DPO\n", cdb[0]);
 807                         return -EINVAL;
 808                 }
 809         }
 810         if (cdb[1] & 0x8) {
 811                 if (!target_check_fua(dev)) {
 812                         pr_err("Got CDB: 0x%02x with FUA bit set, but device"
 813                                " does not advertise support for FUA write\n",
 814                                cdb[0]);
 815                         return -EINVAL;
 816                 }
 817                 cmd->se_cmd_flags |= SCF_FUA;
 818         }
 819         return 0;
 820 }
 821
 822 sense_reason_t
 823 sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 824 {
 825         struct se_device *dev = cmd->se_dev;
 826         unsigned char *cdb = cmd->t_task_cdb;
 827         unsigned int size;
 828         u32 sectors = 0;
 829         sense_reason_t ret;
 830
 831         cmd->protocol_data = ops;
 832
 833         switch (cdb[0]) {
 834         case READ_6:
 835                 sectors = transport_get_sectors_6(cdb);
 836                 cmd->t_task_lba = transport_lba_21(cdb);
 837                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 838                 cmd->execute_cmd = sbc_execute_rw;
 839                 break;
 840         case READ_10:
 841                 sectors = transport_get_sectors_10(cdb);
 842                 cmd->t_task_lba = transport_lba_32(cdb);
 843
 844                 if (sbc_check_dpofua(dev, cmd, cdb))
 845                         return TCM_INVALID_CDB_FIELD;
 846
 847                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 848                 if (ret)
 849                         return ret;
 850
 851                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 852                 cmd->execute_cmd = sbc_execute_rw;
 853                 break;
 854         case READ_12:
 855                 sectors = transport_get_sectors_12(cdb);
 856                 cmd->t_task_lba = transport_lba_32(cdb);
 857
 858                 if (sbc_check_dpofua(dev, cmd, cdb))
 859                         return TCM_INVALID_CDB_FIELD;
 860
 861                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 862                 if (ret)
 863                         return ret;
 864
 865                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 866                 cmd->execute_cmd = sbc_execute_rw;
 867                 break;
 868         case READ_16:
 869                 sectors = transport_get_sectors_16(cdb);
 870                 cmd->t_task_lba = transport_lba_64(cdb);
 871
 872                 if (sbc_check_dpofua(dev, cmd, cdb))
 873                         return TCM_INVALID_CDB_FIELD;
 874
 875                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 876                 if (ret)
 877                         return ret;
 878
 879                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 880                 cmd->execute_cmd = sbc_execute_rw;
 881                 break;
 882         case WRITE_6:
 883                 sectors = transport_get_sectors_6(cdb);
 884                 cmd->t_task_lba = transport_lba_21(cdb);
 885                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 886                 cmd->execute_cmd = sbc_execute_rw;
 887                 break;
 888         case WRITE_10:
 889         case WRITE_VERIFY:
 890                 sectors = transport_get_sectors_10(cdb);
 891                 cmd->t_task_lba = transport_lba_32(cdb);
 892
 893                 if (sbc_check_dpofua(dev, cmd, cdb))
 894                         return TCM_INVALID_CDB_FIELD;
 895
 896                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 897                 if (ret)
 898                         return ret;
 899
 900                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 901                 cmd->execute_cmd = sbc_execute_rw;
 902                 break;
 903         case WRITE_12:
 904                 sectors = transport_get_sectors_12(cdb);
 905                 cmd->t_task_lba = transport_lba_32(cdb);
 906
 907                 if (sbc_check_dpofua(dev, cmd, cdb))
 908                         return TCM_INVALID_CDB_FIELD;
 909
 910                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 911                 if (ret)
 912                         return ret;
 913
 914                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 915                 cmd->execute_cmd = sbc_execute_rw;
 916                 break;
 917         case WRITE_16:
 918                 sectors = transport_get_sectors_16(cdb);
 919                 cmd->t_task_lba = transport_lba_64(cdb);
 920
 921                 if (sbc_check_dpofua(dev, cmd, cdb))
 922                         return TCM_INVALID_CDB_FIELD;
 923
 924                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 925                 if (ret)
 926                         return ret;
 927
 928                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 929                 cmd->execute_cmd = sbc_execute_rw;
 930                 break;
 931         case XDWRITEREAD_10:
 932                 if (cmd->data_direction != DMA_TO_DEVICE ||
 933                     !(cmd->se_cmd_flags & SCF_BIDI))
 934                         return TCM_INVALID_CDB_FIELD;
 935                 sectors = transport_get_sectors_10(cdb);
 936
 937                 if (sbc_check_dpofua(dev, cmd, cdb))
 938                         return TCM_INVALID_CDB_FIELD;
 939
 940                 cmd->t_task_lba = transport_lba_32(cdb);
 941                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 942
 943                 /*
 944                  * Setup BIDI XOR callback to be run after I/O completion.
 945                  */
 946                 cmd->execute_cmd = sbc_execute_rw;
 947                 cmd->transport_complete_callback = &xdreadwrite_callback;
 948                 break;
 949         case VARIABLE_LENGTH_CMD:
 950         {
 951                 u16 service_action = get_unaligned_be16(&cdb[8]);
 952                 switch (service_action) {
 953                 case XDWRITEREAD_32:
 954                         sectors = transport_get_sectors_32(cdb);
 955
 956                         if (sbc_check_dpofua(dev, cmd, cdb))
 957                                 return TCM_INVALID_CDB_FIELD;
 958                         /*
 959                          * Use WRITE_32 and READ_32 opcodes for the emulated
 960                          * XDWRITE_READ_32 logic.
 961                          */
 962                         cmd->t_task_lba = transport_lba_64_ext(cdb);
 963                         cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 964
 965                         /*
 966                          * Setup BIDI XOR callback to be run during after I/O
 967                          * completion.
 968                          */
 969                         cmd->execute_cmd = sbc_execute_rw;
 970                         cmd->transport_complete_callback = &xdreadwrite_callback;
 971                         break;
 972                 case WRITE_SAME_32:
 973                         sectors = transport_get_sectors_32(cdb);
 974                         if (!sectors) {
 975                                 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
 976                                        " supported\n");
 977                                 return TCM_INVALID_CDB_FIELD;
 978                         }
 979
 980                         size = sbc_get_size(cmd, 1);
 981                         cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
 982
 983                         ret = sbc_setup_write_same(cmd, &cdb[10], ops);
 984                         if (ret)
 985                                 return ret;
 986                         break;
 987                 default:
 988                         pr_err("VARIABLE_LENGTH_CMD service action"
 989                                 " 0x%04x not supported\n", service_action);
 990                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 991                 }
 992                 break;
 993         }
 994         case COMPARE_AND_WRITE:
 995                 sectors = cdb[13];
 996                 /*
 997                  * Currently enforce COMPARE_AND_WRITE for a single sector
 998                  */
 999                 if (sectors > 1) {
1000                         pr_err("COMPARE_AND_WRITE contains NoLB: %u greater"
1001                                " than 1\n", sectors);
1002                         return TCM_INVALID_CDB_FIELD;
1003                 }
1004                 if (sbc_check_dpofua(dev, cmd, cdb))
1005                         return TCM_INVALID_CDB_FIELD;
1006
1007                 /*
1008                  * Double size because we have two buffers, note that
1009                  * zero is not an error..
1010                  */
1011                 size = 2 * sbc_get_size(cmd, sectors);
1012                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1013                 cmd->t_task_nolb = sectors;
1014                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE;
1015                 cmd->execute_cmd = sbc_compare_and_write;
1016                 cmd->transport_complete_callback = compare_and_write_callback;
1017                 break;
1018         case READ_CAPACITY:
1019                 size = READ_CAP_LEN;
1020                 cmd->execute_cmd = sbc_emulate_readcapacity;
1021                 break;
1022         case SERVICE_ACTION_IN_16:
1023                 switch (cmd->t_task_cdb[1] & 0x1f) {
1024                 case SAI_READ_CAPACITY_16:
1025                         cmd->execute_cmd = sbc_emulate_readcapacity_16;
1026                         break;
1027                 case SAI_REPORT_REFERRALS:
1028                         cmd->execute_cmd = target_emulate_report_referrals;
1029                         break;
1030                 default:
1031                         pr_err("Unsupported SA: 0x%02x\n",
1032                                 cmd->t_task_cdb[1] & 0x1f);
1033                         return TCM_INVALID_CDB_FIELD;
1034                 }
1035                 size = (cdb[10] << 24) | (cdb[11] << 16) |
1036                        (cdb[12] << 8) | cdb[13];
1037                 break;
1038         case SYNCHRONIZE_CACHE:
1039         case SYNCHRONIZE_CACHE_16:
1040                 if (cdb[0] == SYNCHRONIZE_CACHE) {
1041                         sectors = transport_get_sectors_10(cdb);
1042                         cmd->t_task_lba = transport_lba_32(cdb);
1043                 } else {
1044                         sectors = transport_get_sectors_16(cdb);
1045                         cmd->t_task_lba = transport_lba_64(cdb);
1046                 }
1047                 if (ops->execute_sync_cache) {
1048                         cmd->execute_cmd = ops->execute_sync_cache;
1049                         goto check_lba;
1050                 }
1051                 size = 0;
1052                 cmd->execute_cmd = sbc_emulate_noop;
1053                 break;
1054         case UNMAP:
1055                 if (!ops->execute_unmap)
1056                         return TCM_UNSUPPORTED_SCSI_OPCODE;
1057
1058                 if (!dev->dev_attrib.emulate_tpu) {
1059                         pr_err("Got UNMAP, but backend device has"
1060                                " emulate_tpu disabled\n");
1061                         return TCM_UNSUPPORTED_SCSI_OPCODE;
1062                 }
1063                 size = get_unaligned_be16(&cdb[7]);
1064                 cmd->execute_cmd = sbc_execute_unmap;
1065                 break;
1066         case WRITE_SAME_16:
1067                 sectors = transport_get_sectors_16(cdb);
1068                 if (!sectors) {
1069                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1070                         return TCM_INVALID_CDB_FIELD;
1071                 }
1072
1073                 size = sbc_get_size(cmd, 1);
1074                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1075
1076                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1077                 if (ret)
1078                         return ret;
1079                 break;
1080         case WRITE_SAME:
1081                 sectors = transport_get_sectors_10(cdb);
1082                 if (!sectors) {
1083                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1084                         return TCM_INVALID_CDB_FIELD;
1085                 }
1086
1087                 size = sbc_get_size(cmd, 1);
1088                 cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
1089
1090                 /*
1091                  * Follow sbcr26 with WRITE_SAME (10) and check for the existence
1092                  * of byte 1 bit 3 UNMAP instead of original reserved field
1093                  */
1094                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1095                 if (ret)
1096                         return ret;
1097                 break;
1098         case VERIFY:
1099                 size = 0;
1100                 sectors = transport_get_sectors_10(cdb);
1101                 cmd->t_task_lba = transport_lba_32(cdb);
1102                 cmd->execute_cmd = sbc_emulate_noop;
1103                 goto check_lba;
1104         case REZERO_UNIT:
1105         case SEEK_6:
1106         case SEEK_10:
1107                 /*
1108                  * There are still clients out there which use these old SCSI-2
1109                  * commands. This mainly happens when running VMs with legacy
1110                  * guest systems, connected via SCSI command pass-through to
1111                  * iSCSI targets. Make them happy and return status GOOD.
1112                  */
1113                 size = 0;
1114                 cmd->execute_cmd = sbc_emulate_noop;
1115                 break;
1116         case START_STOP:
1117                 size = 0;
1118                 cmd->execute_cmd = sbc_emulate_startstop;
1119                 break;
1120         default:
1121                 ret = spc_parse_cdb(cmd, &size);
1122                 if (ret)
1123                         return ret;
1124         }
1125
1126         /* reject any command that we don't have a handler for */
1127         if (!cmd->execute_cmd)
1128                 return TCM_UNSUPPORTED_SCSI_OPCODE;
1129
1130         if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1131                 unsigned long long end_lba;
1132 check_lba:
1133                 end_lba = dev->transport->get_blocks(dev) + 1;
1134                 if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
1135                     ((cmd->t_task_lba + sectors) > end_lba)) {
1136                         pr_err("cmd exceeds last lba %llu "
1137                                 "(lba %llu, sectors %u)\n",
1138                                 end_lba, cmd->t_task_lba, sectors);
1139                         return TCM_ADDRESS_OUT_OF_RANGE;
1140                 }
1141
1142                 if (!(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE))
1143                         size = sbc_get_size(cmd, sectors);
1144         }
1145
1146         return target_cmd_size_check(cmd, size);
1147 }
1148 EXPORT_SYMBOL(sbc_parse_cdb);
1149
1150 u32 sbc_get_device_type(struct se_device *dev)
1151 {
1152         return TYPE_DISK;
1153 }
1154 EXPORT_SYMBOL(sbc_get_device_type);
1155
1156 static sense_reason_t
1157 sbc_execute_unmap(struct se_cmd *cmd)
1158 {
1159         struct sbc_ops *ops = cmd->protocol_data;
1160         struct se_device *dev = cmd->se_dev;
1161         unsigned char *buf, *ptr = NULL;
1162         sector_t lba;
1163         int size;
1164         u32 range;
1165         sense_reason_t ret = 0;
1166         int dl, bd_dl;
1167
1168         /* We never set ANC_SUP */
1169         if (cmd->t_task_cdb[1])
1170                 return TCM_INVALID_CDB_FIELD;
1171
1172         if (cmd->data_length == 0) {
1173                 target_complete_cmd(cmd, SAM_STAT_GOOD);
1174                 return 0;
1175         }
1176
1177         if (cmd->data_length < 8) {
1178                 pr_warn("UNMAP parameter list length %u too small\n",
1179                         cmd->data_length);
1180                 return TCM_PARAMETER_LIST_LENGTH_ERROR;
1181         }
1182
1183         buf = transport_kmap_data_sg(cmd);
1184         if (!buf)
1185                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1186
1187         dl = get_unaligned_be16(&buf[0]);
1188         bd_dl = get_unaligned_be16(&buf[2]);
1189
1190         size = cmd->data_length - 8;
1191         if (bd_dl > size)
1192                 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
1193                         cmd->data_length, bd_dl);
1194         else
1195                 size = bd_dl;
1196
1197         if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
1198                 ret = TCM_INVALID_PARAMETER_LIST;
1199                 goto err;
1200         }
1201
1202         /* First UNMAP block descriptor starts at 8 byte offset */
1203         ptr = &buf[8];
1204         pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
1205                 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
1206
1207         while (size >= 16) {
1208                 lba = get_unaligned_be64(&ptr[0]);
1209                 range = get_unaligned_be32(&ptr[8]);
1210                 pr_debug("UNMAP: Using lba: %llu and range: %u\n",
1211                                  (unsigned long long)lba, range);
1212
1213                 if (range > dev->dev_attrib.max_unmap_lba_count) {
1214                         ret = TCM_INVALID_PARAMETER_LIST;
1215                         goto err;
1216                 }
1217
1218                 if (lba + range > dev->transport->get_blocks(dev) + 1) {
1219                         ret = TCM_ADDRESS_OUT_OF_RANGE;
1220                         goto err;
1221                 }
1222
1223                 ret = ops->execute_unmap(cmd, lba, range);
1224                 if (ret)
1225                         goto err;
1226
1227                 ptr += 16;
1228                 size -= 16;
1229         }
1230
1231 err:
1232         transport_kunmap_data_sg(cmd);
1233         if (!ret)
1234                 target_complete_cmd(cmd, GOOD);
1235         return ret;
1236 }
1237
1238 void
1239 sbc_dif_generate(struct se_cmd *cmd)
1240 {
1241         struct se_device *dev = cmd->se_dev;
1242         struct t10_pi_tuple *sdt;
1243         struct scatterlist *dsg = cmd->t_data_sg, *psg;
1244         sector_t sector = cmd->t_task_lba;
1245         void *daddr, *paddr;
1246         int i, j, offset = 0;
1247         unsigned int block_size = dev->dev_attrib.block_size;
1248
1249         for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1250                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1251                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1252
1253                 for (j = 0; j < psg->length;
1254                                 j += sizeof(*sdt)) {
1255                         __u16 crc;
1256                         unsigned int avail;
1257
1258                         if (offset >= dsg->length) {
1259                                 offset -= dsg->length;
1260                                 kunmap_atomic(daddr - dsg->offset);
1261                                 dsg = sg_next(dsg);
1262                                 if (!dsg) {
1263                                         kunmap_atomic(paddr - psg->offset);
1264                                         return;
1265                                 }
1266                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1267                         }
1268
1269                         sdt = paddr + j;
1270                         avail = min(block_size, dsg->length - offset);
1271                         crc = crc_t10dif(daddr + offset, avail);
1272                         if (avail < block_size) {
1273                                 kunmap_atomic(daddr - dsg->offset);
1274                                 dsg = sg_next(dsg);
1275                                 if (!dsg) {
1276                                         kunmap_atomic(paddr - psg->offset);
1277                                         return;
1278                                 }
1279                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1280                                 offset = block_size - avail;
1281                                 crc = crc_t10dif_update(crc, daddr, offset);
1282                         } else {
1283                                 offset += block_size;
1284                         }
1285
1286                         sdt->guard_tag = cpu_to_be16(crc);
1287                         if (cmd->prot_type == TARGET_DIF_TYPE1_PROT)
1288                                 sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
1289                         sdt->app_tag = 0;
1290
1291                         pr_debug("DIF %s INSERT sector: %llu guard_tag: 0x%04x"
1292                                  " app_tag: 0x%04x ref_tag: %u\n",
1293                                  (cmd->data_direction == DMA_TO_DEVICE) ?
1294                                  "WRITE" : "READ", (unsigned long long)sector,
1295                                  sdt->guard_tag, sdt->app_tag,
1296                                  be32_to_cpu(sdt->ref_tag));
1297
1298                         sector++;
1299                 }
1300
1301                 kunmap_atomic(daddr - dsg->offset);
1302                 kunmap_atomic(paddr - psg->offset);
1303         }
1304 }
1305
1306 static sense_reason_t
1307 sbc_dif_v1_verify(struct se_cmd *cmd, struct t10_pi_tuple *sdt,
1308                   __u16 crc, sector_t sector, unsigned int ei_lba)
1309 {
1310         __be16 csum;
1311
1312         if (!(cmd->prot_checks & TARGET_DIF_CHECK_GUARD))
1313                 goto check_ref;
1314
1315         csum = cpu_to_be16(crc);
1316
1317         if (sdt->guard_tag != csum) {
1318                 pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x"
1319                         " csum 0x%04x\n", (unsigned long long)sector,
1320                         be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
1321                 return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
1322         }
1323
1324 check_ref:
1325         if (!(cmd->prot_checks & TARGET_DIF_CHECK_REFTAG))
1326                 return 0;
1327
1328         if (cmd->prot_type == TARGET_DIF_TYPE1_PROT &&
1329             be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
1330                 pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x"
1331                        " sector MSB: 0x%08x\n", (unsigned long long)sector,
1332                        be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff));
1333                 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1334         }
1335
1336         if (cmd->prot_type == TARGET_DIF_TYPE2_PROT &&
1337             be32_to_cpu(sdt->ref_tag) != ei_lba) {
1338                 pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x"
1339                        " ei_lba: 0x%08x\n", (unsigned long long)sector,
1340                         be32_to_cpu(sdt->ref_tag), ei_lba);
1341                 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1342         }
1343
1344         return 0;
1345 }
1346
1347 void sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read,
1348                        struct scatterlist *sg, int sg_off)
1349 {
1350         struct se_device *dev = cmd->se_dev;
1351         struct scatterlist *psg;
1352         void *paddr, *addr;
1353         unsigned int i, len, left;
1354         unsigned int offset = sg_off;
1355
1356         if (!sg)
1357                 return;
1358
1359         left = sectors * dev->prot_length;
1360
1361         for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1362                 unsigned int psg_len, copied = 0;
1363
1364                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1365                 psg_len = min(left, psg->length);
1366                 while (psg_len) {
1367                         len = min(psg_len, sg->length - offset);
1368                         addr = kmap_atomic(sg_page(sg)) + sg->offset + offset;
1369
1370                         if (read)
1371                                 memcpy(paddr + copied, addr, len);
1372                         else
1373                                 memcpy(addr, paddr + copied, len);
1374
1375                         left -= len;
1376                         offset += len;
1377                         copied += len;
1378                         psg_len -= len;
1379
1380                         kunmap_atomic(addr - sg->offset - offset);
1381
1382                         if (offset >= sg->length) {
1383                                 sg = sg_next(sg);
1384                                 offset = 0;
1385                         }
1386                 }
1387                 kunmap_atomic(paddr - psg->offset);
1388         }
1389 }
1390 EXPORT_SYMBOL(sbc_dif_copy_prot);
1391
1392 sense_reason_t
1393 sbc_dif_verify(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1394                unsigned int ei_lba, struct scatterlist *psg, int psg_off)
1395 {
1396         struct se_device *dev = cmd->se_dev;
1397         struct t10_pi_tuple *sdt;
1398         struct scatterlist *dsg = cmd->t_data_sg;
1399         sector_t sector = start;
1400         void *daddr, *paddr;
1401         int i;
1402         sense_reason_t rc;
1403         int dsg_off = 0;
1404         unsigned int block_size = dev->dev_attrib.block_size;
1405
1406         for (; psg && sector < start + sectors; psg = sg_next(psg)) {
1407                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1408                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1409
1410                 for (i = psg_off; i < psg->length &&
1411                                 sector < start + sectors;
1412                                 i += sizeof(*sdt)) {
1413                         __u16 crc;
1414                         unsigned int avail;
1415
1416                         if (dsg_off >= dsg->length) {
1417                                 dsg_off -= dsg->length;
1418                                 kunmap_atomic(daddr - dsg->offset);
1419                                 dsg = sg_next(dsg);
1420                                 if (!dsg) {
1421                                         kunmap_atomic(paddr - psg->offset);
1422                                         return 0;
1423                                 }
1424                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1425                         }
1426
1427                         sdt = paddr + i;
1428
1429                         pr_debug("DIF READ sector: %llu guard_tag: 0x%04x"
1430                                  " app_tag: 0x%04x ref_tag: %u\n",
1431                                  (unsigned long long)sector, sdt->guard_tag,
1432                                  sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1433
1434                         if (sdt->app_tag == cpu_to_be16(0xffff)) {
1435                                 dsg_off += block_size;
1436                                 goto next;
1437                         }
1438
1439                         avail = min(block_size, dsg->length - dsg_off);
1440                         crc = crc_t10dif(daddr + dsg_off, avail);
1441                         if (avail < block_size) {
1442                                 kunmap_atomic(daddr - dsg->offset);
1443                                 dsg = sg_next(dsg);
1444                                 if (!dsg) {
1445                                         kunmap_atomic(paddr - psg->offset);
1446                                         return 0;
1447                                 }
1448                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1449                                 dsg_off = block_size - avail;
1450                                 crc = crc_t10dif_update(crc, daddr, dsg_off);
1451                         } else {
1452                                 dsg_off += block_size;
1453                         }
1454
1455                         rc = sbc_dif_v1_verify(cmd, sdt, crc, sector, ei_lba);
1456                         if (rc) {
1457                                 kunmap_atomic(daddr - dsg->offset);
1458                                 kunmap_atomic(paddr - psg->offset);
1459                                 cmd->bad_sector = sector;
1460                                 return rc;
1461                         }
1462 next:
1463                         sector++;
1464                         ei_lba++;
1465                 }
1466
1467                 psg_off = 0;
1468                 kunmap_atomic(daddr - dsg->offset);
1469                 kunmap_atomic(paddr - psg->offset);
1470         }
1471
1472         return 0;
1473 }
1474 EXPORT_SYMBOL(sbc_dif_verify);