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
 446         /*
 447          * Only set SCF_COMPARE_AND_WRITE_POST to force a response fall-through
 448          * within target_complete_ok_work() if the command was successfully
 449          * sent to the backend driver.
 450          */
 451         spin_lock_irq(&cmd->t_state_lock);
 452         if ((cmd->transport_state & CMD_T_SENT) && !cmd->scsi_status) {
 453                 cmd->se_cmd_flags |= SCF_COMPARE_AND_WRITE_POST;
 454                 *post_ret = 1;
 455         }
 456         spin_unlock_irq(&cmd->t_state_lock);
 457
 458         /*
 459          * Unlock ->caw_sem originally obtained during sbc_compare_and_write()
 460          * before the original READ I/O submission.
 461          */
 462         up(&dev->caw_sem);
 463
 464         return TCM_NO_SENSE;
 465 }
 466
 467 static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool success,
 468                                                  int *post_ret)
 469 {
 470         struct se_device *dev = cmd->se_dev;
 471         struct scatterlist *write_sg = NULL, *sg;
 472         unsigned char *buf = NULL, *addr;
 473         struct sg_mapping_iter m;
 474         unsigned int offset = 0, len;
 475         unsigned int nlbas = cmd->t_task_nolb;
 476         unsigned int block_size = dev->dev_attrib.block_size;
 477         unsigned int compare_len = (nlbas * block_size);
 478         sense_reason_t ret = TCM_NO_SENSE;
 479         int rc, i;
 480
 481         /*
 482          * Handle early failure in transport_generic_request_failure(),
 483          * which will not have taken ->caw_sem yet..
 484          */
 485         if (!success && (!cmd->t_data_sg || !cmd->t_bidi_data_sg))
 486                 return TCM_NO_SENSE;
 487         /*
 488          * Handle special case for zero-length COMPARE_AND_WRITE
 489          */
 490         if (!cmd->data_length)
 491                 goto out;
 492         /*
 493          * Immediately exit + release dev->caw_sem if command has already
 494          * been failed with a non-zero SCSI status.
 495          */
 496         if (cmd->scsi_status) {
 497                 pr_err("compare_and_write_callback: non zero scsi_status:"
 498                         " 0x%02x\n", cmd->scsi_status);
 499                 goto out;
 500         }
 501
 502         buf = kzalloc(cmd->data_length, GFP_KERNEL);
 503         if (!buf) {
 504                 pr_err("Unable to allocate compare_and_write buf\n");
 505                 ret = TCM_OUT_OF_RESOURCES;
 506                 goto out;
 507         }
 508
 509         write_sg = kmalloc(sizeof(struct scatterlist) * cmd->t_data_nents,
 510                            GFP_KERNEL);
 511         if (!write_sg) {
 512                 pr_err("Unable to allocate compare_and_write sg\n");
 513                 ret = TCM_OUT_OF_RESOURCES;
 514                 goto out;
 515         }
 516         sg_init_table(write_sg, cmd->t_data_nents);
 517         /*
 518          * Setup verify and write data payloads from total NumberLBAs.
 519          */
 520         rc = sg_copy_to_buffer(cmd->t_data_sg, cmd->t_data_nents, buf,
 521                                cmd->data_length);
 522         if (!rc) {
 523                 pr_err("sg_copy_to_buffer() failed for compare_and_write\n");
 524                 ret = TCM_OUT_OF_RESOURCES;
 525                 goto out;
 526         }
 527         /*
 528          * Compare against SCSI READ payload against verify payload
 529          */
 530         for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, i) {
 531                 addr = (unsigned char *)kmap_atomic(sg_page(sg));
 532                 if (!addr) {
 533                         ret = TCM_OUT_OF_RESOURCES;
 534                         goto out;
 535                 }
 536
 537                 len = min(sg->length, compare_len);
 538
 539                 if (memcmp(addr, buf + offset, len)) {
 540                         pr_warn("Detected MISCOMPARE for addr: %p buf: %p\n",
 541                                 addr, buf + offset);
 542                         kunmap_atomic(addr);
 543                         goto miscompare;
 544                 }
 545                 kunmap_atomic(addr);
 546
 547                 offset += len;
 548                 compare_len -= len;
 549                 if (!compare_len)
 550                         break;
 551         }
 552
 553         i = 0;
 554         len = cmd->t_task_nolb * block_size;
 555         sg_miter_start(&m, cmd->t_data_sg, cmd->t_data_nents, SG_MITER_TO_SG);
 556         /*
 557          * Currently assumes NoLB=1 and SGLs are PAGE_SIZE..
 558          */
 559         while (len) {
 560                 sg_miter_next(&m);
 561
 562                 if (block_size < PAGE_SIZE) {
 563                         sg_set_page(&write_sg[i], m.page, block_size,
 564                                     m.piter.sg->offset + block_size);
 565                 } else {
 566                         sg_miter_next(&m);
 567                         sg_set_page(&write_sg[i], m.page, block_size,
 568                                     m.piter.sg->offset);
 569                 }
 570                 len -= block_size;
 571                 i++;
 572         }
 573         sg_miter_stop(&m);
 574         /*
 575          * Save the original SGL + nents values before updating to new
 576          * assignments, to be released in transport_free_pages() ->
 577          * transport_reset_sgl_orig()
 578          */
 579         cmd->t_data_sg_orig = cmd->t_data_sg;
 580         cmd->t_data_sg = write_sg;
 581         cmd->t_data_nents_orig = cmd->t_data_nents;
 582         cmd->t_data_nents = 1;
 583
 584         cmd->sam_task_attr = TCM_HEAD_TAG;
 585         cmd->transport_complete_callback = compare_and_write_post;
 586         /*
 587          * Now reset ->execute_cmd() to the normal sbc_execute_rw() handler
 588          * for submitting the adjusted SGL to write instance user-data.
 589          */
 590         cmd->execute_cmd = sbc_execute_rw;
 591
 592         spin_lock_irq(&cmd->t_state_lock);
 593         cmd->t_state = TRANSPORT_PROCESSING;
 594         cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
 595         spin_unlock_irq(&cmd->t_state_lock);
 596
 597         __target_execute_cmd(cmd);
 598
 599         kfree(buf);
 600         return ret;
 601
 602 miscompare:
 603         pr_warn("Target/%s: Send MISCOMPARE check condition and sense\n",
 604                 dev->transport->name);
 605         ret = TCM_MISCOMPARE_VERIFY;
 606 out:
 607         /*
 608          * In the MISCOMPARE or failure case, unlock ->caw_sem obtained in
 609          * sbc_compare_and_write() before the original READ I/O submission.
 610          */
 611         up(&dev->caw_sem);
 612         kfree(write_sg);
 613         kfree(buf);
 614         return ret;
 615 }
 616
 617 static sense_reason_t
 618 sbc_compare_and_write(struct se_cmd *cmd)
 619 {
 620         struct sbc_ops *ops = cmd->protocol_data;
 621         struct se_device *dev = cmd->se_dev;
 622         sense_reason_t ret;
 623         int rc;
 624         /*
 625          * Submit the READ first for COMPARE_AND_WRITE to perform the
 626          * comparision using SGLs at cmd->t_bidi_data_sg..
 627          */
 628         rc = down_interruptible(&dev->caw_sem);
 629         if (rc != 0) {
 630                 cmd->transport_complete_callback = NULL;
 631                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 632         }
 633         /*
 634          * Reset cmd->data_length to individual block_size in order to not
 635          * confuse backend drivers that depend on this value matching the
 636          * size of the I/O being submitted.
 637          */
 638         cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size;
 639
 640         ret = ops->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents,
 641                               DMA_FROM_DEVICE);
 642         if (ret) {
 643                 cmd->transport_complete_callback = NULL;
 644                 up(&dev->caw_sem);
 645                 return ret;
 646         }
 647         /*
 648          * Unlock of dev->caw_sem to occur in compare_and_write_callback()
 649          * upon MISCOMPARE, or in compare_and_write_done() upon completion
 650          * of WRITE instance user-data.
 651          */
 652         return TCM_NO_SENSE;
 653 }
 654
 655 static int
 656 sbc_set_prot_op_checks(u8 protect, bool fabric_prot, enum target_prot_type prot_type,
 657                        bool is_write, struct se_cmd *cmd)
 658 {
 659         if (is_write) {
 660                 cmd->prot_op = fabric_prot ? TARGET_PROT_DOUT_STRIP :
 661                                protect ? TARGET_PROT_DOUT_PASS :
 662                                TARGET_PROT_DOUT_INSERT;
 663                 switch (protect) {
 664                 case 0x0:
 665                 case 0x3:
 666                         cmd->prot_checks = 0;
 667                         break;
 668                 case 0x1:
 669                 case 0x5:
 670                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 671                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 672                                 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 673                         break;
 674                 case 0x2:
 675                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 676                                 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 677                         break;
 678                 case 0x4:
 679                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 680                         break;
 681                 default:
 682                         pr_err("Unsupported protect field %d\n", protect);
 683                         return -EINVAL;
 684                 }
 685         } else {
 686                 cmd->prot_op = fabric_prot ? TARGET_PROT_DIN_INSERT :
 687                                protect ? TARGET_PROT_DIN_PASS :
 688                                TARGET_PROT_DIN_STRIP;
 689                 switch (protect) {
 690                 case 0x0:
 691                 case 0x1:
 692                 case 0x5:
 693                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 694                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 695                                 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 696                         break;
 697                 case 0x2:
 698                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 699                                 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 700                         break;
 701                 case 0x3:
 702                         cmd->prot_checks = 0;
 703                         break;
 704                 case 0x4:
 705                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 706                         break;
 707                 default:
 708                         pr_err("Unsupported protect field %d\n", protect);
 709                         return -EINVAL;
 710                 }
 711         }
 712
 713         return 0;
 714 }
 715
 716 static sense_reason_t
 717 sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb,
 718                u32 sectors, bool is_write)
 719 {
 720         u8 protect = cdb[1] >> 5;
 721         int sp_ops = cmd->se_sess->sup_prot_ops;
 722         int pi_prot_type = dev->dev_attrib.pi_prot_type;
 723         bool fabric_prot = false;
 724
 725         if (!cmd->t_prot_sg || !cmd->t_prot_nents) {
 726                 if (unlikely(protect &&
 727                     !dev->dev_attrib.pi_prot_type && !cmd->se_sess->sess_prot_type)) {
 728                         pr_err("CDB contains protect bit, but device + fabric does"
 729                                " not advertise PROTECT=1 feature bit\n");
 730                         return TCM_INVALID_CDB_FIELD;
 731                 }
 732                 if (cmd->prot_pto)
 733                         return TCM_NO_SENSE;
 734         }
 735
 736         switch (dev->dev_attrib.pi_prot_type) {
 737         case TARGET_DIF_TYPE3_PROT:
 738                 cmd->reftag_seed = 0xffffffff;
 739                 break;
 740         case TARGET_DIF_TYPE2_PROT:
 741                 if (protect)
 742                         return TCM_INVALID_CDB_FIELD;
 743
 744                 cmd->reftag_seed = cmd->t_task_lba;
 745                 break;
 746         case TARGET_DIF_TYPE1_PROT:
 747                 cmd->reftag_seed = cmd->t_task_lba;
 748                 break;
 749         case TARGET_DIF_TYPE0_PROT:
 750                 /*
 751                  * See if the fabric supports T10-PI, and the session has been
 752                  * configured to allow export PROTECT=1 feature bit with backend
 753                  * devices that don't support T10-PI.
 754                  */
 755                 fabric_prot = is_write ?
 756                               !!(sp_ops & (TARGET_PROT_DOUT_PASS | TARGET_PROT_DOUT_STRIP)) :
 757                               !!(sp_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DIN_INSERT));
 758
 759                 if (fabric_prot && cmd->se_sess->sess_prot_type) {
 760                         pi_prot_type = cmd->se_sess->sess_prot_type;
 761                         break;
 762                 }
 763                 if (!protect)
 764                         return TCM_NO_SENSE;
 765                 /* Fallthrough */
 766         default:
 767                 pr_err("Unable to determine pi_prot_type for CDB: 0x%02x "
 768                        "PROTECT: 0x%02x\n", cdb[0], protect);
 769                 return TCM_INVALID_CDB_FIELD;
 770         }
 771
 772         if (sbc_set_prot_op_checks(protect, fabric_prot, pi_prot_type, is_write, cmd))
 773                 return TCM_INVALID_CDB_FIELD;
 774
 775         cmd->prot_type = pi_prot_type;
 776         cmd->prot_length = dev->prot_length * sectors;
 777
 778         /**
 779          * In case protection information exists over the wire
 780          * we modify command data length to describe pure data.
 781          * The actual transfer length is data length + protection
 782          * length
 783          **/
 784         if (protect)
 785                 cmd->data_length = sectors * dev->dev_attrib.block_size;
 786
 787         pr_debug("%s: prot_type=%d, data_length=%d, prot_length=%d "
 788                  "prot_op=%d prot_checks=%d\n",
 789                  __func__, cmd->prot_type, cmd->data_length, cmd->prot_length,
 790                  cmd->prot_op, cmd->prot_checks);
 791
 792         return TCM_NO_SENSE;
 793 }
 794
 795 static int
 796 sbc_check_dpofua(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb)
 797 {
 798         if (cdb[1] & 0x10) {
 799                 /* see explanation in spc_emulate_modesense */
 800                 if (!target_check_fua(dev)) {
 801                         pr_err("Got CDB: 0x%02x with DPO bit set, but device"
 802                                " does not advertise support for DPO\n", cdb[0]);
 803                         return -EINVAL;
 804                 }
 805         }
 806         if (cdb[1] & 0x8) {
 807                 if (!target_check_fua(dev)) {
 808                         pr_err("Got CDB: 0x%02x with FUA bit set, but device"
 809                                " does not advertise support for FUA write\n",
 810                                cdb[0]);
 811                         return -EINVAL;
 812                 }
 813                 cmd->se_cmd_flags |= SCF_FUA;
 814         }
 815         return 0;
 816 }
 817
 818 sense_reason_t
 819 sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 820 {
 821         struct se_device *dev = cmd->se_dev;
 822         unsigned char *cdb = cmd->t_task_cdb;
 823         unsigned int size;
 824         u32 sectors = 0;
 825         sense_reason_t ret;
 826
 827         cmd->protocol_data = ops;
 828
 829         switch (cdb[0]) {
 830         case READ_6:
 831                 sectors = transport_get_sectors_6(cdb);
 832                 cmd->t_task_lba = transport_lba_21(cdb);
 833                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 834                 cmd->execute_cmd = sbc_execute_rw;
 835                 break;
 836         case READ_10:
 837                 sectors = transport_get_sectors_10(cdb);
 838                 cmd->t_task_lba = transport_lba_32(cdb);
 839
 840                 if (sbc_check_dpofua(dev, cmd, cdb))
 841                         return TCM_INVALID_CDB_FIELD;
 842
 843                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 844                 if (ret)
 845                         return ret;
 846
 847                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 848                 cmd->execute_cmd = sbc_execute_rw;
 849                 break;
 850         case READ_12:
 851                 sectors = transport_get_sectors_12(cdb);
 852                 cmd->t_task_lba = transport_lba_32(cdb);
 853
 854                 if (sbc_check_dpofua(dev, cmd, cdb))
 855                         return TCM_INVALID_CDB_FIELD;
 856
 857                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 858                 if (ret)
 859                         return ret;
 860
 861                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 862                 cmd->execute_cmd = sbc_execute_rw;
 863                 break;
 864         case READ_16:
 865                 sectors = transport_get_sectors_16(cdb);
 866                 cmd->t_task_lba = transport_lba_64(cdb);
 867
 868                 if (sbc_check_dpofua(dev, cmd, cdb))
 869                         return TCM_INVALID_CDB_FIELD;
 870
 871                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 872                 if (ret)
 873                         return ret;
 874
 875                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 876                 cmd->execute_cmd = sbc_execute_rw;
 877                 break;
 878         case WRITE_6:
 879                 sectors = transport_get_sectors_6(cdb);
 880                 cmd->t_task_lba = transport_lba_21(cdb);
 881                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 882                 cmd->execute_cmd = sbc_execute_rw;
 883                 break;
 884         case WRITE_10:
 885         case WRITE_VERIFY:
 886                 sectors = transport_get_sectors_10(cdb);
 887                 cmd->t_task_lba = transport_lba_32(cdb);
 888
 889                 if (sbc_check_dpofua(dev, cmd, cdb))
 890                         return TCM_INVALID_CDB_FIELD;
 891
 892                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 893                 if (ret)
 894                         return ret;
 895
 896                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 897                 cmd->execute_cmd = sbc_execute_rw;
 898                 break;
 899         case WRITE_12:
 900                 sectors = transport_get_sectors_12(cdb);
 901                 cmd->t_task_lba = transport_lba_32(cdb);
 902
 903                 if (sbc_check_dpofua(dev, cmd, cdb))
 904                         return TCM_INVALID_CDB_FIELD;
 905
 906                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 907                 if (ret)
 908                         return ret;
 909
 910                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 911                 cmd->execute_cmd = sbc_execute_rw;
 912                 break;
 913         case WRITE_16:
 914                 sectors = transport_get_sectors_16(cdb);
 915                 cmd->t_task_lba = transport_lba_64(cdb);
 916
 917                 if (sbc_check_dpofua(dev, cmd, cdb))
 918                         return TCM_INVALID_CDB_FIELD;
 919
 920                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 921                 if (ret)
 922                         return ret;
 923
 924                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 925                 cmd->execute_cmd = sbc_execute_rw;
 926                 break;
 927         case XDWRITEREAD_10:
 928                 if (cmd->data_direction != DMA_TO_DEVICE ||
 929                     !(cmd->se_cmd_flags & SCF_BIDI))
 930                         return TCM_INVALID_CDB_FIELD;
 931                 sectors = transport_get_sectors_10(cdb);
 932
 933                 if (sbc_check_dpofua(dev, cmd, cdb))
 934                         return TCM_INVALID_CDB_FIELD;
 935
 936                 cmd->t_task_lba = transport_lba_32(cdb);
 937                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 938
 939                 /*
 940                  * Setup BIDI XOR callback to be run after I/O completion.
 941                  */
 942                 cmd->execute_cmd = sbc_execute_rw;
 943                 cmd->transport_complete_callback = &xdreadwrite_callback;
 944                 break;
 945         case VARIABLE_LENGTH_CMD:
 946         {
 947                 u16 service_action = get_unaligned_be16(&cdb[8]);
 948                 switch (service_action) {
 949                 case XDWRITEREAD_32:
 950                         sectors = transport_get_sectors_32(cdb);
 951
 952                         if (sbc_check_dpofua(dev, cmd, cdb))
 953                                 return TCM_INVALID_CDB_FIELD;
 954                         /*
 955                          * Use WRITE_32 and READ_32 opcodes for the emulated
 956                          * XDWRITE_READ_32 logic.
 957                          */
 958                         cmd->t_task_lba = transport_lba_64_ext(cdb);
 959                         cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 960
 961                         /*
 962                          * Setup BIDI XOR callback to be run during after I/O
 963                          * completion.
 964                          */
 965                         cmd->execute_cmd = sbc_execute_rw;
 966                         cmd->transport_complete_callback = &xdreadwrite_callback;
 967                         break;
 968                 case WRITE_SAME_32:
 969                         sectors = transport_get_sectors_32(cdb);
 970                         if (!sectors) {
 971                                 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
 972                                        " supported\n");
 973                                 return TCM_INVALID_CDB_FIELD;
 974                         }
 975
 976                         size = sbc_get_size(cmd, 1);
 977                         cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
 978
 979                         ret = sbc_setup_write_same(cmd, &cdb[10], ops);
 980                         if (ret)
 981                                 return ret;
 982                         break;
 983                 default:
 984                         pr_err("VARIABLE_LENGTH_CMD service action"
 985                                 " 0x%04x not supported\n", service_action);
 986                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 987                 }
 988                 break;
 989         }
 990         case COMPARE_AND_WRITE:
 991                 sectors = cdb[13];
 992                 /*
 993                  * Currently enforce COMPARE_AND_WRITE for a single sector
 994                  */
 995                 if (sectors > 1) {
 996                         pr_err("COMPARE_AND_WRITE contains NoLB: %u greater"
 997                                " than 1\n", sectors);
 998                         return TCM_INVALID_CDB_FIELD;
 999                 }
1000                 if (sbc_check_dpofua(dev, cmd, cdb))
1001                         return TCM_INVALID_CDB_FIELD;
1002
1003                 /*
1004                  * Double size because we have two buffers, note that
1005                  * zero is not an error..
1006                  */
1007                 size = 2 * sbc_get_size(cmd, sectors);
1008                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1009                 cmd->t_task_nolb = sectors;
1010                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE;
1011                 cmd->execute_cmd = sbc_compare_and_write;
1012                 cmd->transport_complete_callback = compare_and_write_callback;
1013                 break;
1014         case READ_CAPACITY:
1015                 size = READ_CAP_LEN;
1016                 cmd->execute_cmd = sbc_emulate_readcapacity;
1017                 break;
1018         case SERVICE_ACTION_IN_16:
1019                 switch (cmd->t_task_cdb[1] & 0x1f) {
1020                 case SAI_READ_CAPACITY_16:
1021                         cmd->execute_cmd = sbc_emulate_readcapacity_16;
1022                         break;
1023                 case SAI_REPORT_REFERRALS:
1024                         cmd->execute_cmd = target_emulate_report_referrals;
1025                         break;
1026                 default:
1027                         pr_err("Unsupported SA: 0x%02x\n",
1028                                 cmd->t_task_cdb[1] & 0x1f);
1029                         return TCM_INVALID_CDB_FIELD;
1030                 }
1031                 size = (cdb[10] << 24) | (cdb[11] << 16) |
1032                        (cdb[12] << 8) | cdb[13];
1033                 break;
1034         case SYNCHRONIZE_CACHE:
1035         case SYNCHRONIZE_CACHE_16:
1036                 if (cdb[0] == SYNCHRONIZE_CACHE) {
1037                         sectors = transport_get_sectors_10(cdb);
1038                         cmd->t_task_lba = transport_lba_32(cdb);
1039                 } else {
1040                         sectors = transport_get_sectors_16(cdb);
1041                         cmd->t_task_lba = transport_lba_64(cdb);
1042                 }
1043                 if (ops->execute_sync_cache) {
1044                         cmd->execute_cmd = ops->execute_sync_cache;
1045                         goto check_lba;
1046                 }
1047                 size = 0;
1048                 cmd->execute_cmd = sbc_emulate_noop;
1049                 break;
1050         case UNMAP:
1051                 if (!ops->execute_unmap)
1052                         return TCM_UNSUPPORTED_SCSI_OPCODE;
1053
1054                 if (!dev->dev_attrib.emulate_tpu) {
1055                         pr_err("Got UNMAP, but backend device has"
1056                                " emulate_tpu disabled\n");
1057                         return TCM_UNSUPPORTED_SCSI_OPCODE;
1058                 }
1059                 size = get_unaligned_be16(&cdb[7]);
1060                 cmd->execute_cmd = sbc_execute_unmap;
1061                 break;
1062         case WRITE_SAME_16:
1063                 sectors = transport_get_sectors_16(cdb);
1064                 if (!sectors) {
1065                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1066                         return TCM_INVALID_CDB_FIELD;
1067                 }
1068
1069                 size = sbc_get_size(cmd, 1);
1070                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1071
1072                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1073                 if (ret)
1074                         return ret;
1075                 break;
1076         case WRITE_SAME:
1077                 sectors = transport_get_sectors_10(cdb);
1078                 if (!sectors) {
1079                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1080                         return TCM_INVALID_CDB_FIELD;
1081                 }
1082
1083                 size = sbc_get_size(cmd, 1);
1084                 cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
1085
1086                 /*
1087                  * Follow sbcr26 with WRITE_SAME (10) and check for the existence
1088                  * of byte 1 bit 3 UNMAP instead of original reserved field
1089                  */
1090                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1091                 if (ret)
1092                         return ret;
1093                 break;
1094         case VERIFY:
1095                 size = 0;
1096                 sectors = transport_get_sectors_10(cdb);
1097                 cmd->t_task_lba = transport_lba_32(cdb);
1098                 cmd->execute_cmd = sbc_emulate_noop;
1099                 goto check_lba;
1100         case REZERO_UNIT:
1101         case SEEK_6:
1102         case SEEK_10:
1103                 /*
1104                  * There are still clients out there which use these old SCSI-2
1105                  * commands. This mainly happens when running VMs with legacy
1106                  * guest systems, connected via SCSI command pass-through to
1107                  * iSCSI targets. Make them happy and return status GOOD.
1108                  */
1109                 size = 0;
1110                 cmd->execute_cmd = sbc_emulate_noop;
1111                 break;
1112         case START_STOP:
1113                 size = 0;
1114                 cmd->execute_cmd = sbc_emulate_startstop;
1115                 break;
1116         default:
1117                 ret = spc_parse_cdb(cmd, &size);
1118                 if (ret)
1119                         return ret;
1120         }
1121
1122         /* reject any command that we don't have a handler for */
1123         if (!cmd->execute_cmd)
1124                 return TCM_UNSUPPORTED_SCSI_OPCODE;
1125
1126         if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1127                 unsigned long long end_lba;
1128 check_lba:
1129                 end_lba = dev->transport->get_blocks(dev) + 1;
1130                 if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
1131                     ((cmd->t_task_lba + sectors) > end_lba)) {
1132                         pr_err("cmd exceeds last lba %llu "
1133                                 "(lba %llu, sectors %u)\n",
1134                                 end_lba, cmd->t_task_lba, sectors);
1135                         return TCM_ADDRESS_OUT_OF_RANGE;
1136                 }
1137
1138                 if (!(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE))
1139                         size = sbc_get_size(cmd, sectors);
1140         }
1141
1142         return target_cmd_size_check(cmd, size);
1143 }
1144 EXPORT_SYMBOL(sbc_parse_cdb);
1145
1146 u32 sbc_get_device_type(struct se_device *dev)
1147 {
1148         return TYPE_DISK;
1149 }
1150 EXPORT_SYMBOL(sbc_get_device_type);
1151
1152 static sense_reason_t
1153 sbc_execute_unmap(struct se_cmd *cmd)
1154 {
1155         struct sbc_ops *ops = cmd->protocol_data;
1156         struct se_device *dev = cmd->se_dev;
1157         unsigned char *buf, *ptr = NULL;
1158         sector_t lba;
1159         int size;
1160         u32 range;
1161         sense_reason_t ret = 0;
1162         int dl, bd_dl;
1163
1164         /* We never set ANC_SUP */
1165         if (cmd->t_task_cdb[1])
1166                 return TCM_INVALID_CDB_FIELD;
1167
1168         if (cmd->data_length == 0) {
1169                 target_complete_cmd(cmd, SAM_STAT_GOOD);
1170                 return 0;
1171         }
1172
1173         if (cmd->data_length < 8) {
1174                 pr_warn("UNMAP parameter list length %u too small\n",
1175                         cmd->data_length);
1176                 return TCM_PARAMETER_LIST_LENGTH_ERROR;
1177         }
1178
1179         buf = transport_kmap_data_sg(cmd);
1180         if (!buf)
1181                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1182
1183         dl = get_unaligned_be16(&buf[0]);
1184         bd_dl = get_unaligned_be16(&buf[2]);
1185
1186         size = cmd->data_length - 8;
1187         if (bd_dl > size)
1188                 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
1189                         cmd->data_length, bd_dl);
1190         else
1191                 size = bd_dl;
1192
1193         if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
1194                 ret = TCM_INVALID_PARAMETER_LIST;
1195                 goto err;
1196         }
1197
1198         /* First UNMAP block descriptor starts at 8 byte offset */
1199         ptr = &buf[8];
1200         pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
1201                 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
1202
1203         while (size >= 16) {
1204                 lba = get_unaligned_be64(&ptr[0]);
1205                 range = get_unaligned_be32(&ptr[8]);
1206                 pr_debug("UNMAP: Using lba: %llu and range: %u\n",
1207                                  (unsigned long long)lba, range);
1208
1209                 if (range > dev->dev_attrib.max_unmap_lba_count) {
1210                         ret = TCM_INVALID_PARAMETER_LIST;
1211                         goto err;
1212                 }
1213
1214                 if (lba + range > dev->transport->get_blocks(dev) + 1) {
1215                         ret = TCM_ADDRESS_OUT_OF_RANGE;
1216                         goto err;
1217                 }
1218
1219                 ret = ops->execute_unmap(cmd, lba, range);
1220                 if (ret)
1221                         goto err;
1222
1223                 ptr += 16;
1224                 size -= 16;
1225         }
1226
1227 err:
1228         transport_kunmap_data_sg(cmd);
1229         if (!ret)
1230                 target_complete_cmd(cmd, GOOD);
1231         return ret;
1232 }
1233
1234 void
1235 sbc_dif_generate(struct se_cmd *cmd)
1236 {
1237         struct se_device *dev = cmd->se_dev;
1238         struct t10_pi_tuple *sdt;
1239         struct scatterlist *dsg = cmd->t_data_sg, *psg;
1240         sector_t sector = cmd->t_task_lba;
1241         void *daddr, *paddr;
1242         int i, j, offset = 0;
1243         unsigned int block_size = dev->dev_attrib.block_size;
1244
1245         for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1246                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1247                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1248
1249                 for (j = 0; j < psg->length;
1250                                 j += sizeof(*sdt)) {
1251                         __u16 crc;
1252                         unsigned int avail;
1253
1254                         if (offset >= dsg->length) {
1255                                 offset -= dsg->length;
1256                                 kunmap_atomic(daddr - dsg->offset);
1257                                 dsg = sg_next(dsg);
1258                                 if (!dsg) {
1259                                         kunmap_atomic(paddr - psg->offset);
1260                                         return;
1261                                 }
1262                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1263                         }
1264
1265                         sdt = paddr + j;
1266                         avail = min(block_size, dsg->length - offset);
1267                         crc = crc_t10dif(daddr + offset, avail);
1268                         if (avail < block_size) {
1269                                 kunmap_atomic(daddr - dsg->offset);
1270                                 dsg = sg_next(dsg);
1271                                 if (!dsg) {
1272                                         kunmap_atomic(paddr - psg->offset);
1273                                         return;
1274                                 }
1275                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1276                                 offset = block_size - avail;
1277                                 crc = crc_t10dif_update(crc, daddr, offset);
1278                         } else {
1279                                 offset += block_size;
1280                         }
1281
1282                         sdt->guard_tag = cpu_to_be16(crc);
1283                         if (cmd->prot_type == TARGET_DIF_TYPE1_PROT)
1284                                 sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
1285                         sdt->app_tag = 0;
1286
1287                         pr_debug("DIF %s INSERT sector: %llu guard_tag: 0x%04x"
1288                                  " app_tag: 0x%04x ref_tag: %u\n",
1289                                  (cmd->data_direction == DMA_TO_DEVICE) ?
1290                                  "WRITE" : "READ", (unsigned long long)sector,
1291                                  sdt->guard_tag, sdt->app_tag,
1292                                  be32_to_cpu(sdt->ref_tag));
1293
1294                         sector++;
1295                 }
1296
1297                 kunmap_atomic(daddr - dsg->offset);
1298                 kunmap_atomic(paddr - psg->offset);
1299         }
1300 }
1301
1302 static sense_reason_t
1303 sbc_dif_v1_verify(struct se_cmd *cmd, struct t10_pi_tuple *sdt,
1304                   __u16 crc, sector_t sector, unsigned int ei_lba)
1305 {
1306         __be16 csum;
1307
1308         if (!(cmd->prot_checks & TARGET_DIF_CHECK_GUARD))
1309                 goto check_ref;
1310
1311         csum = cpu_to_be16(crc);
1312
1313         if (sdt->guard_tag != csum) {
1314                 pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x"
1315                         " csum 0x%04x\n", (unsigned long long)sector,
1316                         be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
1317                 return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
1318         }
1319
1320 check_ref:
1321         if (!(cmd->prot_checks & TARGET_DIF_CHECK_REFTAG))
1322                 return 0;
1323
1324         if (cmd->prot_type == TARGET_DIF_TYPE1_PROT &&
1325             be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
1326                 pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x"
1327                        " sector MSB: 0x%08x\n", (unsigned long long)sector,
1328                        be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff));
1329                 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1330         }
1331
1332         if (cmd->prot_type == TARGET_DIF_TYPE2_PROT &&
1333             be32_to_cpu(sdt->ref_tag) != ei_lba) {
1334                 pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x"
1335                        " ei_lba: 0x%08x\n", (unsigned long long)sector,
1336                         be32_to_cpu(sdt->ref_tag), ei_lba);
1337                 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1338         }
1339
1340         return 0;
1341 }
1342
1343 void sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read,
1344                        struct scatterlist *sg, int sg_off)
1345 {
1346         struct se_device *dev = cmd->se_dev;
1347         struct scatterlist *psg;
1348         void *paddr, *addr;
1349         unsigned int i, len, left;
1350         unsigned int offset = sg_off;
1351
1352         if (!sg)
1353                 return;
1354
1355         left = sectors * dev->prot_length;
1356
1357         for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1358                 unsigned int psg_len, copied = 0;
1359
1360                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1361                 psg_len = min(left, psg->length);
1362                 while (psg_len) {
1363                         len = min(psg_len, sg->length - offset);
1364                         addr = kmap_atomic(sg_page(sg)) + sg->offset + offset;
1365
1366                         if (read)
1367                                 memcpy(paddr + copied, addr, len);
1368                         else
1369                                 memcpy(addr, paddr + copied, len);
1370
1371                         left -= len;
1372                         offset += len;
1373                         copied += len;
1374                         psg_len -= len;
1375
1376                         kunmap_atomic(addr - sg->offset - offset);
1377
1378                         if (offset >= sg->length) {
1379                                 sg = sg_next(sg);
1380                                 offset = 0;
1381                         }
1382                 }
1383                 kunmap_atomic(paddr - psg->offset);
1384         }
1385 }
1386 EXPORT_SYMBOL(sbc_dif_copy_prot);
1387
1388 sense_reason_t
1389 sbc_dif_verify(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1390                unsigned int ei_lba, struct scatterlist *psg, int psg_off)
1391 {
1392         struct se_device *dev = cmd->se_dev;
1393         struct t10_pi_tuple *sdt;
1394         struct scatterlist *dsg = cmd->t_data_sg;
1395         sector_t sector = start;
1396         void *daddr, *paddr;
1397         int i;
1398         sense_reason_t rc;
1399         int dsg_off = 0;
1400         unsigned int block_size = dev->dev_attrib.block_size;
1401
1402         for (; psg && sector < start + sectors; psg = sg_next(psg)) {
1403                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1404                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1405
1406                 for (i = psg_off; i < psg->length &&
1407                                 sector < start + sectors;
1408                                 i += sizeof(*sdt)) {
1409                         __u16 crc;
1410                         unsigned int avail;
1411
1412                         if (dsg_off >= dsg->length) {
1413                                 dsg_off -= dsg->length;
1414                                 kunmap_atomic(daddr - dsg->offset);
1415                                 dsg = sg_next(dsg);
1416                                 if (!dsg) {
1417                                         kunmap_atomic(paddr - psg->offset);
1418                                         return 0;
1419                                 }
1420                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1421                         }
1422
1423                         sdt = paddr + i;
1424
1425                         pr_debug("DIF READ sector: %llu guard_tag: 0x%04x"
1426                                  " app_tag: 0x%04x ref_tag: %u\n",
1427                                  (unsigned long long)sector, sdt->guard_tag,
1428                                  sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1429
1430                         if (sdt->app_tag == cpu_to_be16(0xffff)) {
1431                                 dsg_off += block_size;
1432                                 goto next;
1433                         }
1434
1435                         avail = min(block_size, dsg->length - dsg_off);
1436                         crc = crc_t10dif(daddr + dsg_off, avail);
1437                         if (avail < block_size) {
1438                                 kunmap_atomic(daddr - dsg->offset);
1439                                 dsg = sg_next(dsg);
1440                                 if (!dsg) {
1441                                         kunmap_atomic(paddr - psg->offset);
1442                                         return 0;
1443                                 }
1444                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1445                                 dsg_off = block_size - avail;
1446                                 crc = crc_t10dif_update(crc, daddr, dsg_off);
1447                         } else {
1448                                 dsg_off += block_size;
1449                         }
1450
1451                         rc = sbc_dif_v1_verify(cmd, sdt, crc, sector, ei_lba);
1452                         if (rc) {
1453                                 kunmap_atomic(daddr - dsg->offset);
1454                                 kunmap_atomic(paddr - psg->offset);
1455                                 cmd->bad_sector = sector;
1456                                 return rc;
1457                         }
1458 next:
1459                         sector++;
1460                         ei_lba++;
1461                 }
1462
1463                 psg_off = 0;
1464                 kunmap_atomic(daddr - dsg->offset);
1465                 kunmap_atomic(paddr - psg->offset);
1466         }
1467
1468         return 0;
1469 }
1470 EXPORT_SYMBOL(sbc_dif_verify);