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 <[email protected]>
   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 {
 376         unsigned char *buf, *addr;
 377         struct scatterlist *sg;
 378         unsigned int offset;
 379         sense_reason_t ret = TCM_NO_SENSE;
 380         int i, count;
 381         /*
 382          * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
 383          *
 384          * 1) read the specified logical block(s);
 385          * 2) transfer logical blocks from the data-out buffer;
 386          * 3) XOR the logical blocks transferred from the data-out buffer with
 387          *    the logical blocks read, storing the resulting XOR data in a buffer;
 388          * 4) if the DISABLE WRITE bit is set to zero, then write the logical
 389          *    blocks transferred from the data-out buffer; and
 390          * 5) transfer the resulting XOR data to the data-in buffer.
 391          */
 392         buf = kmalloc(cmd->data_length, GFP_KERNEL);
 393         if (!buf) {
 394                 pr_err("Unable to allocate xor_callback buf\n");
 395                 return TCM_OUT_OF_RESOURCES;
 396         }
 397         /*
 398          * Copy the scatterlist WRITE buffer located at cmd->t_data_sg
 399          * into the locally allocated *buf
 400          */
 401         sg_copy_to_buffer(cmd->t_data_sg,
 402                           cmd->t_data_nents,
 403                           buf,
 404                           cmd->data_length);
 405
 406         /*
 407          * Now perform the XOR against the BIDI read memory located at
 408          * cmd->t_mem_bidi_list
 409          */
 410
 411         offset = 0;
 412         for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
 413                 addr = kmap_atomic(sg_page(sg));
 414                 if (!addr) {
 415                         ret = TCM_OUT_OF_RESOURCES;
 416                         goto out;
 417                 }
 418
 419                 for (i = 0; i < sg->length; i++)
 420                         *(addr + sg->offset + i) ^= *(buf + offset + i);
 421
 422                 offset += sg->length;
 423                 kunmap_atomic(addr);
 424         }
 425
 426 out:
 427         kfree(buf);
 428         return ret;
 429 }
 430
 431 static sense_reason_t
 432 sbc_execute_rw(struct se_cmd *cmd)
 433 {
 434         struct sbc_ops *ops = cmd->protocol_data;
 435
 436         return ops->execute_rw(cmd, cmd->t_data_sg, cmd->t_data_nents,
 437                                cmd->data_direction);
 438 }
 439
 440 static sense_reason_t compare_and_write_post(struct se_cmd *cmd, bool success)
 441 {
 442         struct se_device *dev = cmd->se_dev;
 443
 444         /*
 445          * Only set SCF_COMPARE_AND_WRITE_POST to force a response fall-through
 446          * within target_complete_ok_work() if the command was successfully
 447          * sent to the backend driver.
 448          */
 449         spin_lock_irq(&cmd->t_state_lock);
 450         if ((cmd->transport_state & CMD_T_SENT) && !cmd->scsi_status)
 451                 cmd->se_cmd_flags |= SCF_COMPARE_AND_WRITE_POST;
 452         spin_unlock_irq(&cmd->t_state_lock);
 453
 454         /*
 455          * Unlock ->caw_sem originally obtained during sbc_compare_and_write()
 456          * before the original READ I/O submission.
 457          */
 458         up(&dev->caw_sem);
 459
 460         return TCM_NO_SENSE;
 461 }
 462
 463 static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool success)
 464 {
 465         struct se_device *dev = cmd->se_dev;
 466         struct scatterlist *write_sg = NULL, *sg;
 467         unsigned char *buf = NULL, *addr;
 468         struct sg_mapping_iter m;
 469         unsigned int offset = 0, len;
 470         unsigned int nlbas = cmd->t_task_nolb;
 471         unsigned int block_size = dev->dev_attrib.block_size;
 472         unsigned int compare_len = (nlbas * block_size);
 473         sense_reason_t ret = TCM_NO_SENSE;
 474         int rc, i;
 475
 476         /*
 477          * Handle early failure in transport_generic_request_failure(),
 478          * which will not have taken ->caw_sem yet..
 479          */
 480         if (!success && (!cmd->t_data_sg || !cmd->t_bidi_data_sg))
 481                 return TCM_NO_SENSE;
 482         /*
 483          * Handle special case for zero-length COMPARE_AND_WRITE
 484          */
 485         if (!cmd->data_length)
 486                 goto out;
 487         /*
 488          * Immediately exit + release dev->caw_sem if command has already
 489          * been failed with a non-zero SCSI status.
 490          */
 491         if (cmd->scsi_status) {
 492                 pr_err("compare_and_write_callback: non zero scsi_status:"
 493                         " 0x%02x\n", cmd->scsi_status);
 494                 goto out;
 495         }
 496
 497         buf = kzalloc(cmd->data_length, GFP_KERNEL);
 498         if (!buf) {
 499                 pr_err("Unable to allocate compare_and_write buf\n");
 500                 ret = TCM_OUT_OF_RESOURCES;
 501                 goto out;
 502         }
 503
 504         write_sg = kmalloc(sizeof(struct scatterlist) * cmd->t_data_nents,
 505                            GFP_KERNEL);
 506         if (!write_sg) {
 507                 pr_err("Unable to allocate compare_and_write sg\n");
 508                 ret = TCM_OUT_OF_RESOURCES;
 509                 goto out;
 510         }
 511         sg_init_table(write_sg, cmd->t_data_nents);
 512         /*
 513          * Setup verify and write data payloads from total NumberLBAs.
 514          */
 515         rc = sg_copy_to_buffer(cmd->t_data_sg, cmd->t_data_nents, buf,
 516                                cmd->data_length);
 517         if (!rc) {
 518                 pr_err("sg_copy_to_buffer() failed for compare_and_write\n");
 519                 ret = TCM_OUT_OF_RESOURCES;
 520                 goto out;
 521         }
 522         /*
 523          * Compare against SCSI READ payload against verify payload
 524          */
 525         for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, i) {
 526                 addr = (unsigned char *)kmap_atomic(sg_page(sg));
 527                 if (!addr) {
 528                         ret = TCM_OUT_OF_RESOURCES;
 529                         goto out;
 530                 }
 531
 532                 len = min(sg->length, compare_len);
 533
 534                 if (memcmp(addr, buf + offset, len)) {
 535                         pr_warn("Detected MISCOMPARE for addr: %p buf: %p\n",
 536                                 addr, buf + offset);
 537                         kunmap_atomic(addr);
 538                         goto miscompare;
 539                 }
 540                 kunmap_atomic(addr);
 541
 542                 offset += len;
 543                 compare_len -= len;
 544                 if (!compare_len)
 545                         break;
 546         }
 547
 548         i = 0;
 549         len = cmd->t_task_nolb * block_size;
 550         sg_miter_start(&m, cmd->t_data_sg, cmd->t_data_nents, SG_MITER_TO_SG);
 551         /*
 552          * Currently assumes NoLB=1 and SGLs are PAGE_SIZE..
 553          */
 554         while (len) {
 555                 sg_miter_next(&m);
 556
 557                 if (block_size < PAGE_SIZE) {
 558                         sg_set_page(&write_sg[i], m.page, block_size,
 559                                     block_size);
 560                 } else {
 561                         sg_miter_next(&m);
 562                         sg_set_page(&write_sg[i], m.page, block_size,
 563                                     0);
 564                 }
 565                 len -= block_size;
 566                 i++;
 567         }
 568         sg_miter_stop(&m);
 569         /*
 570          * Save the original SGL + nents values before updating to new
 571          * assignments, to be released in transport_free_pages() ->
 572          * transport_reset_sgl_orig()
 573          */
 574         cmd->t_data_sg_orig = cmd->t_data_sg;
 575         cmd->t_data_sg = write_sg;
 576         cmd->t_data_nents_orig = cmd->t_data_nents;
 577         cmd->t_data_nents = 1;
 578
 579         cmd->sam_task_attr = TCM_HEAD_TAG;
 580         cmd->transport_complete_callback = compare_and_write_post;
 581         /*
 582          * Now reset ->execute_cmd() to the normal sbc_execute_rw() handler
 583          * for submitting the adjusted SGL to write instance user-data.
 584          */
 585         cmd->execute_cmd = sbc_execute_rw;
 586
 587         spin_lock_irq(&cmd->t_state_lock);
 588         cmd->t_state = TRANSPORT_PROCESSING;
 589         cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
 590         spin_unlock_irq(&cmd->t_state_lock);
 591
 592         __target_execute_cmd(cmd);
 593
 594         kfree(buf);
 595         return ret;
 596
 597 miscompare:
 598         pr_warn("Target/%s: Send MISCOMPARE check condition and sense\n",
 599                 dev->transport->name);
 600         ret = TCM_MISCOMPARE_VERIFY;
 601 out:
 602         /*
 603          * In the MISCOMPARE or failure case, unlock ->caw_sem obtained in
 604          * sbc_compare_and_write() before the original READ I/O submission.
 605          */
 606         up(&dev->caw_sem);
 607         kfree(write_sg);
 608         kfree(buf);
 609         return ret;
 610 }
 611
 612 static sense_reason_t
 613 sbc_compare_and_write(struct se_cmd *cmd)
 614 {
 615         struct sbc_ops *ops = cmd->protocol_data;
 616         struct se_device *dev = cmd->se_dev;
 617         sense_reason_t ret;
 618         int rc;
 619         /*
 620          * Submit the READ first for COMPARE_AND_WRITE to perform the
 621          * comparision using SGLs at cmd->t_bidi_data_sg..
 622          */
 623         rc = down_interruptible(&dev->caw_sem);
 624         if (rc != 0) {
 625                 cmd->transport_complete_callback = NULL;
 626                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 627         }
 628         /*
 629          * Reset cmd->data_length to individual block_size in order to not
 630          * confuse backend drivers that depend on this value matching the
 631          * size of the I/O being submitted.
 632          */
 633         cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size;
 634
 635         ret = ops->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents,
 636                               DMA_FROM_DEVICE);
 637         if (ret) {
 638                 cmd->transport_complete_callback = NULL;
 639                 up(&dev->caw_sem);
 640                 return ret;
 641         }
 642         /*
 643          * Unlock of dev->caw_sem to occur in compare_and_write_callback()
 644          * upon MISCOMPARE, or in compare_and_write_done() upon completion
 645          * of WRITE instance user-data.
 646          */
 647         return TCM_NO_SENSE;
 648 }
 649
 650 static int
 651 sbc_set_prot_op_checks(u8 protect, bool fabric_prot, enum target_prot_type prot_type,
 652                        bool is_write, struct se_cmd *cmd)
 653 {
 654         if (is_write) {
 655                 cmd->prot_op = fabric_prot ? TARGET_PROT_DOUT_STRIP :
 656                                protect ? TARGET_PROT_DOUT_PASS :
 657                                TARGET_PROT_DOUT_INSERT;
 658                 switch (protect) {
 659                 case 0x0:
 660                 case 0x3:
 661                         cmd->prot_checks = 0;
 662                         break;
 663                 case 0x1:
 664                 case 0x5:
 665                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 666                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 667                                 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 668                         break;
 669                 case 0x2:
 670                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 671                                 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 672                         break;
 673                 case 0x4:
 674                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 675                         break;
 676                 default:
 677                         pr_err("Unsupported protect field %d\n", protect);
 678                         return -EINVAL;
 679                 }
 680         } else {
 681                 cmd->prot_op = fabric_prot ? TARGET_PROT_DIN_INSERT :
 682                                protect ? TARGET_PROT_DIN_PASS :
 683                                TARGET_PROT_DIN_STRIP;
 684                 switch (protect) {
 685                 case 0x0:
 686                 case 0x1:
 687                 case 0x5:
 688                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 689                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 690                                 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 691                         break;
 692                 case 0x2:
 693                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 694                                 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 695                         break;
 696                 case 0x3:
 697                         cmd->prot_checks = 0;
 698                         break;
 699                 case 0x4:
 700                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 701                         break;
 702                 default:
 703                         pr_err("Unsupported protect field %d\n", protect);
 704                         return -EINVAL;
 705                 }
 706         }
 707
 708         return 0;
 709 }
 710
 711 static sense_reason_t
 712 sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb,
 713                u32 sectors, bool is_write)
 714 {
 715         u8 protect = cdb[1] >> 5;
 716         int sp_ops = cmd->se_sess->sup_prot_ops;
 717         int pi_prot_type = dev->dev_attrib.pi_prot_type;
 718         bool fabric_prot = false;
 719
 720         if (!cmd->t_prot_sg || !cmd->t_prot_nents) {
 721                 if (unlikely(protect &&
 722                     !dev->dev_attrib.pi_prot_type && !cmd->se_sess->sess_prot_type)) {
 723                         pr_err("CDB contains protect bit, but device + fabric does"
 724                                " not advertise PROTECT=1 feature bit\n");
 725                         return TCM_INVALID_CDB_FIELD;
 726                 }
 727                 if (cmd->prot_pto)
 728                         return TCM_NO_SENSE;
 729         }
 730
 731         switch (dev->dev_attrib.pi_prot_type) {
 732         case TARGET_DIF_TYPE3_PROT:
 733                 cmd->reftag_seed = 0xffffffff;
 734                 break;
 735         case TARGET_DIF_TYPE2_PROT:
 736                 if (protect)
 737                         return TCM_INVALID_CDB_FIELD;
 738
 739                 cmd->reftag_seed = cmd->t_task_lba;
 740                 break;
 741         case TARGET_DIF_TYPE1_PROT:
 742                 cmd->reftag_seed = cmd->t_task_lba;
 743                 break;
 744         case TARGET_DIF_TYPE0_PROT:
 745                 /*
 746                  * See if the fabric supports T10-PI, and the session has been
 747                  * configured to allow export PROTECT=1 feature bit with backend
 748                  * devices that don't support T10-PI.
 749                  */
 750                 fabric_prot = is_write ?
 751                               !!(sp_ops & (TARGET_PROT_DOUT_PASS | TARGET_PROT_DOUT_STRIP)) :
 752                               !!(sp_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DIN_INSERT));
 753
 754                 if (fabric_prot && cmd->se_sess->sess_prot_type) {
 755                         pi_prot_type = cmd->se_sess->sess_prot_type;
 756                         break;
 757                 }
 758                 if (!protect)
 759                         return TCM_NO_SENSE;
 760                 /* Fallthrough */
 761         default:
 762                 pr_err("Unable to determine pi_prot_type for CDB: 0x%02x "
 763                        "PROTECT: 0x%02x\n", cdb[0], protect);
 764                 return TCM_INVALID_CDB_FIELD;
 765         }
 766
 767         if (sbc_set_prot_op_checks(protect, fabric_prot, pi_prot_type, is_write, cmd))
 768                 return TCM_INVALID_CDB_FIELD;
 769
 770         cmd->prot_type = pi_prot_type;
 771         cmd->prot_length = dev->prot_length * sectors;
 772
 773         /**
 774          * In case protection information exists over the wire
 775          * we modify command data length to describe pure data.
 776          * The actual transfer length is data length + protection
 777          * length
 778          **/
 779         if (protect)
 780                 cmd->data_length = sectors * dev->dev_attrib.block_size;
 781
 782         pr_debug("%s: prot_type=%d, data_length=%d, prot_length=%d "
 783                  "prot_op=%d prot_checks=%d\n",
 784                  __func__, cmd->prot_type, cmd->data_length, cmd->prot_length,
 785                  cmd->prot_op, cmd->prot_checks);
 786
 787         return TCM_NO_SENSE;
 788 }
 789
 790 static int
 791 sbc_check_dpofua(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb)
 792 {
 793         if (cdb[1] & 0x10) {
 794                 /* see explanation in spc_emulate_modesense */
 795                 if (!target_check_fua(dev)) {
 796                         pr_err("Got CDB: 0x%02x with DPO bit set, but device"
 797                                " does not advertise support for DPO\n", cdb[0]);
 798                         return -EINVAL;
 799                 }
 800         }
 801         if (cdb[1] & 0x8) {
 802                 if (!target_check_fua(dev)) {
 803                         pr_err("Got CDB: 0x%02x with FUA bit set, but device"
 804                                " does not advertise support for FUA write\n",
 805                                cdb[0]);
 806                         return -EINVAL;
 807                 }
 808                 cmd->se_cmd_flags |= SCF_FUA;
 809         }
 810         return 0;
 811 }
 812
 813 sense_reason_t
 814 sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 815 {
 816         struct se_device *dev = cmd->se_dev;
 817         unsigned char *cdb = cmd->t_task_cdb;
 818         unsigned int size;
 819         u32 sectors = 0;
 820         sense_reason_t ret;
 821
 822         cmd->protocol_data = ops;
 823
 824         switch (cdb[0]) {
 825         case READ_6:
 826                 sectors = transport_get_sectors_6(cdb);
 827                 cmd->t_task_lba = transport_lba_21(cdb);
 828                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 829                 cmd->execute_cmd = sbc_execute_rw;
 830                 break;
 831         case READ_10:
 832                 sectors = transport_get_sectors_10(cdb);
 833                 cmd->t_task_lba = transport_lba_32(cdb);
 834
 835                 if (sbc_check_dpofua(dev, cmd, cdb))
 836                         return TCM_INVALID_CDB_FIELD;
 837
 838                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 839                 if (ret)
 840                         return ret;
 841
 842                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 843                 cmd->execute_cmd = sbc_execute_rw;
 844                 break;
 845         case READ_12:
 846                 sectors = transport_get_sectors_12(cdb);
 847                 cmd->t_task_lba = transport_lba_32(cdb);
 848
 849                 if (sbc_check_dpofua(dev, cmd, cdb))
 850                         return TCM_INVALID_CDB_FIELD;
 851
 852                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 853                 if (ret)
 854                         return ret;
 855
 856                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 857                 cmd->execute_cmd = sbc_execute_rw;
 858                 break;
 859         case READ_16:
 860                 sectors = transport_get_sectors_16(cdb);
 861                 cmd->t_task_lba = transport_lba_64(cdb);
 862
 863                 if (sbc_check_dpofua(dev, cmd, cdb))
 864                         return TCM_INVALID_CDB_FIELD;
 865
 866                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 867                 if (ret)
 868                         return ret;
 869
 870                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 871                 cmd->execute_cmd = sbc_execute_rw;
 872                 break;
 873         case WRITE_6:
 874                 sectors = transport_get_sectors_6(cdb);
 875                 cmd->t_task_lba = transport_lba_21(cdb);
 876                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 877                 cmd->execute_cmd = sbc_execute_rw;
 878                 break;
 879         case WRITE_10:
 880         case WRITE_VERIFY:
 881                 sectors = transport_get_sectors_10(cdb);
 882                 cmd->t_task_lba = transport_lba_32(cdb);
 883
 884                 if (sbc_check_dpofua(dev, cmd, cdb))
 885                         return TCM_INVALID_CDB_FIELD;
 886
 887                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 888                 if (ret)
 889                         return ret;
 890
 891                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 892                 cmd->execute_cmd = sbc_execute_rw;
 893                 break;
 894         case WRITE_12:
 895                 sectors = transport_get_sectors_12(cdb);
 896                 cmd->t_task_lba = transport_lba_32(cdb);
 897
 898                 if (sbc_check_dpofua(dev, cmd, cdb))
 899                         return TCM_INVALID_CDB_FIELD;
 900
 901                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 902                 if (ret)
 903                         return ret;
 904
 905                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 906                 cmd->execute_cmd = sbc_execute_rw;
 907                 break;
 908         case WRITE_16:
 909                 sectors = transport_get_sectors_16(cdb);
 910                 cmd->t_task_lba = transport_lba_64(cdb);
 911
 912                 if (sbc_check_dpofua(dev, cmd, cdb))
 913                         return TCM_INVALID_CDB_FIELD;
 914
 915                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 916                 if (ret)
 917                         return ret;
 918
 919                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 920                 cmd->execute_cmd = sbc_execute_rw;
 921                 break;
 922         case XDWRITEREAD_10:
 923                 if (cmd->data_direction != DMA_TO_DEVICE ||
 924                     !(cmd->se_cmd_flags & SCF_BIDI))
 925                         return TCM_INVALID_CDB_FIELD;
 926                 sectors = transport_get_sectors_10(cdb);
 927
 928                 if (sbc_check_dpofua(dev, cmd, cdb))
 929                         return TCM_INVALID_CDB_FIELD;
 930
 931                 cmd->t_task_lba = transport_lba_32(cdb);
 932                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 933
 934                 /*
 935                  * Setup BIDI XOR callback to be run after I/O completion.
 936                  */
 937                 cmd->execute_cmd = sbc_execute_rw;
 938                 cmd->transport_complete_callback = &xdreadwrite_callback;
 939                 break;
 940         case VARIABLE_LENGTH_CMD:
 941         {
 942                 u16 service_action = get_unaligned_be16(&cdb[8]);
 943                 switch (service_action) {
 944                 case XDWRITEREAD_32:
 945                         sectors = transport_get_sectors_32(cdb);
 946
 947                         if (sbc_check_dpofua(dev, cmd, cdb))
 948                                 return TCM_INVALID_CDB_FIELD;
 949                         /*
 950                          * Use WRITE_32 and READ_32 opcodes for the emulated
 951                          * XDWRITE_READ_32 logic.
 952                          */
 953                         cmd->t_task_lba = transport_lba_64_ext(cdb);
 954                         cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 955
 956                         /*
 957                          * Setup BIDI XOR callback to be run during after I/O
 958                          * completion.
 959                          */
 960                         cmd->execute_cmd = sbc_execute_rw;
 961                         cmd->transport_complete_callback = &xdreadwrite_callback;
 962                         break;
 963                 case WRITE_SAME_32:
 964                         sectors = transport_get_sectors_32(cdb);
 965                         if (!sectors) {
 966                                 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
 967                                        " supported\n");
 968                                 return TCM_INVALID_CDB_FIELD;
 969                         }
 970
 971                         size = sbc_get_size(cmd, 1);
 972                         cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
 973
 974                         ret = sbc_setup_write_same(cmd, &cdb[10], ops);
 975                         if (ret)
 976                                 return ret;
 977                         break;
 978                 default:
 979                         pr_err("VARIABLE_LENGTH_CMD service action"
 980                                 " 0x%04x not supported\n", service_action);
 981                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 982                 }
 983                 break;
 984         }
 985         case COMPARE_AND_WRITE:
 986                 sectors = cdb[13];
 987                 /*
 988                  * Currently enforce COMPARE_AND_WRITE for a single sector
 989                  */
 990                 if (sectors > 1) {
 991                         pr_err("COMPARE_AND_WRITE contains NoLB: %u greater"
 992                                " than 1\n", sectors);
 993                         return TCM_INVALID_CDB_FIELD;
 994                 }
 995                 if (sbc_check_dpofua(dev, cmd, cdb))
 996                         return TCM_INVALID_CDB_FIELD;
 997
 998                 /*
 999                  * Double size because we have two buffers, note that
1000                  * zero is not an error..
1001                  */
1002                 size = 2 * sbc_get_size(cmd, sectors);
1003                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1004                 cmd->t_task_nolb = sectors;
1005                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE;
1006                 cmd->execute_cmd = sbc_compare_and_write;
1007                 cmd->transport_complete_callback = compare_and_write_callback;
1008                 break;
1009         case READ_CAPACITY:
1010                 size = READ_CAP_LEN;
1011                 cmd->execute_cmd = sbc_emulate_readcapacity;
1012                 break;
1013         case SERVICE_ACTION_IN_16:
1014                 switch (cmd->t_task_cdb[1] & 0x1f) {
1015                 case SAI_READ_CAPACITY_16:
1016                         cmd->execute_cmd = sbc_emulate_readcapacity_16;
1017                         break;
1018                 case SAI_REPORT_REFERRALS:
1019                         cmd->execute_cmd = target_emulate_report_referrals;
1020                         break;
1021                 default:
1022                         pr_err("Unsupported SA: 0x%02x\n",
1023                                 cmd->t_task_cdb[1] & 0x1f);
1024                         return TCM_INVALID_CDB_FIELD;
1025                 }
1026                 size = (cdb[10] << 24) | (cdb[11] << 16) |
1027                        (cdb[12] << 8) | cdb[13];
1028                 break;
1029         case SYNCHRONIZE_CACHE:
1030         case SYNCHRONIZE_CACHE_16:
1031                 if (cdb[0] == SYNCHRONIZE_CACHE) {
1032                         sectors = transport_get_sectors_10(cdb);
1033                         cmd->t_task_lba = transport_lba_32(cdb);
1034                 } else {
1035                         sectors = transport_get_sectors_16(cdb);
1036                         cmd->t_task_lba = transport_lba_64(cdb);
1037                 }
1038                 if (ops->execute_sync_cache) {
1039                         cmd->execute_cmd = ops->execute_sync_cache;
1040                         goto check_lba;
1041                 }
1042                 size = 0;
1043                 cmd->execute_cmd = sbc_emulate_noop;
1044                 break;
1045         case UNMAP:
1046                 if (!ops->execute_unmap)
1047                         return TCM_UNSUPPORTED_SCSI_OPCODE;
1048
1049                 if (!dev->dev_attrib.emulate_tpu) {
1050                         pr_err("Got UNMAP, but backend device has"
1051                                " emulate_tpu disabled\n");
1052                         return TCM_UNSUPPORTED_SCSI_OPCODE;
1053                 }
1054                 size = get_unaligned_be16(&cdb[7]);
1055                 cmd->execute_cmd = sbc_execute_unmap;
1056                 break;
1057         case WRITE_SAME_16:
1058                 sectors = transport_get_sectors_16(cdb);
1059                 if (!sectors) {
1060                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1061                         return TCM_INVALID_CDB_FIELD;
1062                 }
1063
1064                 size = sbc_get_size(cmd, 1);
1065                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1066
1067                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1068                 if (ret)
1069                         return ret;
1070                 break;
1071         case WRITE_SAME:
1072                 sectors = transport_get_sectors_10(cdb);
1073                 if (!sectors) {
1074                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1075                         return TCM_INVALID_CDB_FIELD;
1076                 }
1077
1078                 size = sbc_get_size(cmd, 1);
1079                 cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
1080
1081                 /*
1082                  * Follow sbcr26 with WRITE_SAME (10) and check for the existence
1083                  * of byte 1 bit 3 UNMAP instead of original reserved field
1084                  */
1085                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1086                 if (ret)
1087                         return ret;
1088                 break;
1089         case VERIFY:
1090                 size = 0;
1091                 sectors = transport_get_sectors_10(cdb);
1092                 cmd->t_task_lba = transport_lba_32(cdb);
1093                 cmd->execute_cmd = sbc_emulate_noop;
1094                 goto check_lba;
1095         case REZERO_UNIT:
1096         case SEEK_6:
1097         case SEEK_10:
1098                 /*
1099                  * There are still clients out there which use these old SCSI-2
1100                  * commands. This mainly happens when running VMs with legacy
1101                  * guest systems, connected via SCSI command pass-through to
1102                  * iSCSI targets. Make them happy and return status GOOD.
1103                  */
1104                 size = 0;
1105                 cmd->execute_cmd = sbc_emulate_noop;
1106                 break;
1107         case START_STOP:
1108                 size = 0;
1109                 cmd->execute_cmd = sbc_emulate_startstop;
1110                 break;
1111         default:
1112                 ret = spc_parse_cdb(cmd, &size);
1113                 if (ret)
1114                         return ret;
1115         }
1116
1117         /* reject any command that we don't have a handler for */
1118         if (!cmd->execute_cmd)
1119                 return TCM_UNSUPPORTED_SCSI_OPCODE;
1120
1121         if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1122                 unsigned long long end_lba;
1123 check_lba:
1124                 end_lba = dev->transport->get_blocks(dev) + 1;
1125                 if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
1126                     ((cmd->t_task_lba + sectors) > end_lba)) {
1127                         pr_err("cmd exceeds last lba %llu "
1128                                 "(lba %llu, sectors %u)\n",
1129                                 end_lba, cmd->t_task_lba, sectors);
1130                         return TCM_ADDRESS_OUT_OF_RANGE;
1131                 }
1132
1133                 if (!(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE))
1134                         size = sbc_get_size(cmd, sectors);
1135         }
1136
1137         return target_cmd_size_check(cmd, size);
1138 }
1139 EXPORT_SYMBOL(sbc_parse_cdb);
1140
1141 u32 sbc_get_device_type(struct se_device *dev)
1142 {
1143         return TYPE_DISK;
1144 }
1145 EXPORT_SYMBOL(sbc_get_device_type);
1146
1147 static sense_reason_t
1148 sbc_execute_unmap(struct se_cmd *cmd)
1149 {
1150         struct sbc_ops *ops = cmd->protocol_data;
1151         struct se_device *dev = cmd->se_dev;
1152         unsigned char *buf, *ptr = NULL;
1153         sector_t lba;
1154         int size;
1155         u32 range;
1156         sense_reason_t ret = 0;
1157         int dl, bd_dl;
1158
1159         /* We never set ANC_SUP */
1160         if (cmd->t_task_cdb[1])
1161                 return TCM_INVALID_CDB_FIELD;
1162
1163         if (cmd->data_length == 0) {
1164                 target_complete_cmd(cmd, SAM_STAT_GOOD);
1165                 return 0;
1166         }
1167
1168         if (cmd->data_length < 8) {
1169                 pr_warn("UNMAP parameter list length %u too small\n",
1170                         cmd->data_length);
1171                 return TCM_PARAMETER_LIST_LENGTH_ERROR;
1172         }
1173
1174         buf = transport_kmap_data_sg(cmd);
1175         if (!buf)
1176                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1177
1178         dl = get_unaligned_be16(&buf[0]);
1179         bd_dl = get_unaligned_be16(&buf[2]);
1180
1181         size = cmd->data_length - 8;
1182         if (bd_dl > size)
1183                 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
1184                         cmd->data_length, bd_dl);
1185         else
1186                 size = bd_dl;
1187
1188         if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
1189                 ret = TCM_INVALID_PARAMETER_LIST;
1190                 goto err;
1191         }
1192
1193         /* First UNMAP block descriptor starts at 8 byte offset */
1194         ptr = &buf[8];
1195         pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
1196                 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
1197
1198         while (size >= 16) {
1199                 lba = get_unaligned_be64(&ptr[0]);
1200                 range = get_unaligned_be32(&ptr[8]);
1201                 pr_debug("UNMAP: Using lba: %llu and range: %u\n",
1202                                  (unsigned long long)lba, range);
1203
1204                 if (range > dev->dev_attrib.max_unmap_lba_count) {
1205                         ret = TCM_INVALID_PARAMETER_LIST;
1206                         goto err;
1207                 }
1208
1209                 if (lba + range > dev->transport->get_blocks(dev) + 1) {
1210                         ret = TCM_ADDRESS_OUT_OF_RANGE;
1211                         goto err;
1212                 }
1213
1214                 ret = ops->execute_unmap(cmd, lba, range);
1215                 if (ret)
1216                         goto err;
1217
1218                 ptr += 16;
1219                 size -= 16;
1220         }
1221
1222 err:
1223         transport_kunmap_data_sg(cmd);
1224         if (!ret)
1225                 target_complete_cmd(cmd, GOOD);
1226         return ret;
1227 }
1228
1229 void
1230 sbc_dif_generate(struct se_cmd *cmd)
1231 {
1232         struct se_device *dev = cmd->se_dev;
1233         struct t10_pi_tuple *sdt;
1234         struct scatterlist *dsg = cmd->t_data_sg, *psg;
1235         sector_t sector = cmd->t_task_lba;
1236         void *daddr, *paddr;
1237         int i, j, offset = 0;
1238         unsigned int block_size = dev->dev_attrib.block_size;
1239
1240         for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1241                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1242                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1243
1244                 for (j = 0; j < psg->length;
1245                                 j += sizeof(*sdt)) {
1246                         __u16 crc;
1247                         unsigned int avail;
1248
1249                         if (offset >= dsg->length) {
1250                                 offset -= dsg->length;
1251                                 kunmap_atomic(daddr - dsg->offset);
1252                                 dsg = sg_next(dsg);
1253                                 if (!dsg) {
1254                                         kunmap_atomic(paddr - psg->offset);
1255                                         return;
1256                                 }
1257                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1258                         }
1259
1260                         sdt = paddr + j;
1261                         avail = min(block_size, dsg->length - offset);
1262                         crc = crc_t10dif(daddr + offset, avail);
1263                         if (avail < block_size) {
1264                                 kunmap_atomic(daddr - dsg->offset);
1265                                 dsg = sg_next(dsg);
1266                                 if (!dsg) {
1267                                         kunmap_atomic(paddr - psg->offset);
1268                                         return;
1269                                 }
1270                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1271                                 offset = block_size - avail;
1272                                 crc = crc_t10dif_update(crc, daddr, offset);
1273                         } else {
1274                                 offset += block_size;
1275                         }
1276
1277                         sdt->guard_tag = cpu_to_be16(crc);
1278                         if (cmd->prot_type == TARGET_DIF_TYPE1_PROT)
1279                                 sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
1280                         sdt->app_tag = 0;
1281
1282                         pr_debug("DIF %s INSERT sector: %llu guard_tag: 0x%04x"
1283                                  " app_tag: 0x%04x ref_tag: %u\n",
1284                                  (cmd->data_direction == DMA_TO_DEVICE) ?
1285                                  "WRITE" : "READ", (unsigned long long)sector,
1286                                  sdt->guard_tag, sdt->app_tag,
1287                                  be32_to_cpu(sdt->ref_tag));
1288
1289                         sector++;
1290                 }
1291
1292                 kunmap_atomic(daddr - dsg->offset);
1293                 kunmap_atomic(paddr - psg->offset);
1294         }
1295 }
1296
1297 static sense_reason_t
1298 sbc_dif_v1_verify(struct se_cmd *cmd, struct t10_pi_tuple *sdt,
1299                   __u16 crc, sector_t sector, unsigned int ei_lba)
1300 {
1301         __be16 csum;
1302
1303         if (!(cmd->prot_checks & TARGET_DIF_CHECK_GUARD))
1304                 goto check_ref;
1305
1306         csum = cpu_to_be16(crc);
1307
1308         if (sdt->guard_tag != csum) {
1309                 pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x"
1310                         " csum 0x%04x\n", (unsigned long long)sector,
1311                         be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
1312                 return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
1313         }
1314
1315 check_ref:
1316         if (!(cmd->prot_checks & TARGET_DIF_CHECK_REFTAG))
1317                 return 0;
1318
1319         if (cmd->prot_type == TARGET_DIF_TYPE1_PROT &&
1320             be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
1321                 pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x"
1322                        " sector MSB: 0x%08x\n", (unsigned long long)sector,
1323                        be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff));
1324                 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1325         }
1326
1327         if (cmd->prot_type == TARGET_DIF_TYPE2_PROT &&
1328             be32_to_cpu(sdt->ref_tag) != ei_lba) {
1329                 pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x"
1330                        " ei_lba: 0x%08x\n", (unsigned long long)sector,
1331                         be32_to_cpu(sdt->ref_tag), ei_lba);
1332                 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1333         }
1334
1335         return 0;
1336 }
1337
1338 void sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read,
1339                        struct scatterlist *sg, int sg_off)
1340 {
1341         struct se_device *dev = cmd->se_dev;
1342         struct scatterlist *psg;
1343         void *paddr, *addr;
1344         unsigned int i, len, left;
1345         unsigned int offset = sg_off;
1346
1347         if (!sg)
1348                 return;
1349
1350         left = sectors * dev->prot_length;
1351
1352         for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1353                 unsigned int psg_len, copied = 0;
1354
1355                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1356                 psg_len = min(left, psg->length);
1357                 while (psg_len) {
1358                         len = min(psg_len, sg->length - offset);
1359                         addr = kmap_atomic(sg_page(sg)) + sg->offset + offset;
1360
1361                         if (read)
1362                                 memcpy(paddr + copied, addr, len);
1363                         else
1364                                 memcpy(addr, paddr + copied, len);
1365
1366                         left -= len;
1367                         offset += len;
1368                         copied += len;
1369                         psg_len -= len;
1370
1371                         kunmap_atomic(addr - sg->offset - offset);
1372
1373                         if (offset >= sg->length) {
1374                                 sg = sg_next(sg);
1375                                 offset = 0;
1376                         }
1377                 }
1378                 kunmap_atomic(paddr - psg->offset);
1379         }
1380 }
1381 EXPORT_SYMBOL(sbc_dif_copy_prot);
1382
1383 sense_reason_t
1384 sbc_dif_verify(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1385                unsigned int ei_lba, struct scatterlist *psg, int psg_off)
1386 {
1387         struct se_device *dev = cmd->se_dev;
1388         struct t10_pi_tuple *sdt;
1389         struct scatterlist *dsg = cmd->t_data_sg;
1390         sector_t sector = start;
1391         void *daddr, *paddr;
1392         int i;
1393         sense_reason_t rc;
1394         int dsg_off = 0;
1395         unsigned int block_size = dev->dev_attrib.block_size;
1396
1397         for (; psg && sector < start + sectors; psg = sg_next(psg)) {
1398                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1399                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1400
1401                 for (i = psg_off; i < psg->length &&
1402                                 sector < start + sectors;
1403                                 i += sizeof(*sdt)) {
1404                         __u16 crc;
1405                         unsigned int avail;
1406
1407                         if (dsg_off >= dsg->length) {
1408                                 dsg_off -= dsg->length;
1409                                 kunmap_atomic(daddr - dsg->offset);
1410                                 dsg = sg_next(dsg);
1411                                 if (!dsg) {
1412                                         kunmap_atomic(paddr - psg->offset);
1413                                         return 0;
1414                                 }
1415                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1416                         }
1417
1418                         sdt = paddr + i;
1419
1420                         pr_debug("DIF READ sector: %llu guard_tag: 0x%04x"
1421                                  " app_tag: 0x%04x ref_tag: %u\n",
1422                                  (unsigned long long)sector, sdt->guard_tag,
1423                                  sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1424
1425                         if (sdt->app_tag == cpu_to_be16(0xffff)) {
1426                                 dsg_off += block_size;
1427                                 goto next;
1428                         }
1429
1430                         avail = min(block_size, dsg->length - dsg_off);
1431                         crc = crc_t10dif(daddr + dsg_off, avail);
1432                         if (avail < block_size) {
1433                                 kunmap_atomic(daddr - dsg->offset);
1434                                 dsg = sg_next(dsg);
1435                                 if (!dsg) {
1436                                         kunmap_atomic(paddr - psg->offset);
1437                                         return 0;
1438                                 }
1439                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1440                                 dsg_off = block_size - avail;
1441                                 crc = crc_t10dif_update(crc, daddr, dsg_off);
1442                         } else {
1443                                 dsg_off += block_size;
1444                         }
1445
1446                         rc = sbc_dif_v1_verify(cmd, sdt, crc, sector, ei_lba);
1447                         if (rc) {
1448                                 kunmap_atomic(daddr - dsg->offset);
1449                                 kunmap_atomic(paddr - psg->offset);
1450                                 cmd->bad_sector = sector;
1451                                 return rc;
1452                         }
1453 next:
1454                         sector++;
1455                         ei_lba++;
1456                 }
1457
1458                 psg_off = 0;
1459                 kunmap_atomic(daddr - dsg->offset);
1460                 kunmap_atomic(paddr - psg->offset);
1461         }
1462
1463         return 0;
1464 }
1465 EXPORT_SYMBOL(sbc_dif_verify);