drivers/target/target_core

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This source file includes following definitions.
sbc_emulate_readcapacity
sbc_emulate_readcapacity_16
sbc_emulate_startstop
sbc_get_write_same_sectors
sbc_execute_write_same_unmap
sbc_emulate_noop
sbc_get_size
transport_get_sectors_6
transport_get_sectors_10
transport_get_sectors_12
transport_get_sectors_16
transport_get_sectors_32
transport_lba_21
transport_lba_32
transport_lba_64
transport_lba_64_ext
sbc_setup_write_same
xdreadwrite_callback
sbc_execute_rw
compare_and_write_post
compare_and_write_callback
sbc_compare_and_write
sbc_set_prot_op_checks
sbc_check_prot
sbc_check_dpofua
sbc_parse_cdb
sbc_get_device_type
sbc_execute_unmap
sbc_dif_generate
sbc_dif_v1_verify
sbc_dif_copy_prot
sbc_dif_verify
   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * SCSI Block Commands (SBC) parsing and emulation.
   4  *
   5  * (c) Copyright 2002-2013 Datera, Inc.
   6  *
   7  * Nicholas A. Bellinger <nab@kernel.org>
   8  */
   9 
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12 #include <linux/ratelimit.h>
  13 #include <linux/crc-t10dif.h>
  14 #include <linux/t10-pi.h>
  15 #include <asm/unaligned.h>
  16 #include <scsi/scsi_proto.h>
  17 #include <scsi/scsi_tcq.h>
  18 
  19 #include <target/target_core_base.h>
  20 #include <target/target_core_backend.h>
  21 #include <target/target_core_fabric.h>
  22 
  23 #include "target_core_internal.h"
  24 #include "target_core_ua.h"
  25 #include "target_core_alua.h"
  26 
  27 static sense_reason_t
  28 sbc_check_prot(struct se_device *, struct se_cmd *, unsigned char *, u32, bool);
  29 static sense_reason_t sbc_execute_unmap(struct se_cmd *cmd);
  30 
  31 static sense_reason_t
  32 sbc_emulate_readcapacity(struct se_cmd *cmd)
  33 {
  34         struct se_device *dev = cmd->se_dev;
  35         unsigned char *cdb = cmd->t_task_cdb;
  36         unsigned long long blocks_long = dev->transport->get_blocks(dev);
  37         unsigned char *rbuf;
  38         unsigned char buf[8];
  39         u32 blocks;
  40 
  41         /*
  42          * SBC-2 says:
  43          *   If the PMI bit is set to zero and the LOGICAL BLOCK
  44          *   ADDRESS field is not set to zero, the device server shall
  45          *   terminate the command with CHECK CONDITION status with
  46          *   the sense key set to ILLEGAL REQUEST and the additional
  47          *   sense code set to INVALID FIELD IN CDB.
  48          *
  49          * In SBC-3, these fields are obsolete, but some SCSI
  50          * compliance tests actually check this, so we might as well
  51          * follow SBC-2.
  52          */
  53         if (!(cdb[8] & 1) && !!(cdb[2] | cdb[3] | cdb[4] | cdb[5]))
  54                 return TCM_INVALID_CDB_FIELD;
  55 
  56         if (blocks_long >= 0x00000000ffffffff)
  57                 blocks = 0xffffffff;
  58         else
  59                 blocks = (u32)blocks_long;
  60 
  61         put_unaligned_be32(blocks, &buf[0]);
  62         put_unaligned_be32(dev->dev_attrib.block_size, &buf[4]);
  63 
  64         rbuf = transport_kmap_data_sg(cmd);
  65         if (rbuf) {
  66                 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
  67                 transport_kunmap_data_sg(cmd);
  68         }
  69 
  70         target_complete_cmd_with_length(cmd, GOOD, 8);
  71         return 0;
  72 }
  73 
  74 static sense_reason_t
  75 sbc_emulate_readcapacity_16(struct se_cmd *cmd)
  76 {
  77         struct se_device *dev = cmd->se_dev;
  78         struct se_session *sess = cmd->se_sess;
  79         int pi_prot_type = dev->dev_attrib.pi_prot_type;
  80 
  81         unsigned char *rbuf;
  82         unsigned char buf[32];
  83         unsigned long long blocks = dev->transport->get_blocks(dev);
  84 
  85         memset(buf, 0, sizeof(buf));
  86         put_unaligned_be64(blocks, &buf[0]);
  87         put_unaligned_be32(dev->dev_attrib.block_size, &buf[8]);
  88         /*
  89          * Set P_TYPE and PROT_EN bits for DIF support
  90          */
  91         if (sess->sup_prot_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS)) {
  92                 /*
  93                  * Only override a device's pi_prot_type if no T10-PI is
  94                  * available, and sess_prot_type has been explicitly enabled.
  95                  */
  96                 if (!pi_prot_type)
  97                         pi_prot_type = sess->sess_prot_type;
  98 
  99                 if (pi_prot_type)
 100                         buf[12] = (pi_prot_type - 1) << 1 | 0x1;
 101         }
 102 
 103         if (dev->transport->get_lbppbe)
 104                 buf[13] = dev->transport->get_lbppbe(dev) & 0x0f;
 105 
 106         if (dev->transport->get_alignment_offset_lbas) {
 107                 u16 lalba = dev->transport->get_alignment_offset_lbas(dev);
 108 
 109                 put_unaligned_be16(lalba, &buf[14]);
 110         }
 111 
 112         /*
 113          * Set Thin Provisioning Enable bit following sbc3r22 in section
 114          * READ CAPACITY (16) byte 14 if emulate_tpu or emulate_tpws is enabled.
 115          */
 116         if (dev->dev_attrib.emulate_tpu || dev->dev_attrib.emulate_tpws) {
 117                 buf[14] |= 0x80;
 118 
 119                 /*
 120                  * LBPRZ signifies that zeroes will be read back from an LBA after
 121                  * an UNMAP or WRITE SAME w/ unmap bit (sbc3r36 5.16.2)
 122                  */
 123                 if (dev->dev_attrib.unmap_zeroes_data)
 124                         buf[14] |= 0x40;
 125         }
 126 
 127         rbuf = transport_kmap_data_sg(cmd);
 128         if (rbuf) {
 129                 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
 130                 transport_kunmap_data_sg(cmd);
 131         }
 132 
 133         target_complete_cmd_with_length(cmd, GOOD, 32);
 134         return 0;
 135 }
 136 
 137 static sense_reason_t
 138 sbc_emulate_startstop(struct se_cmd *cmd)
 139 {
 140         unsigned char *cdb = cmd->t_task_cdb;
 141 
 142         /*
 143          * See sbc3r36 section 5.25
 144          * Immediate bit should be set since there is nothing to complete
 145          * POWER CONDITION MODIFIER 0h
 146          */
 147         if (!(cdb[1] & 1) || cdb[2] || cdb[3])
 148                 return TCM_INVALID_CDB_FIELD;
 149 
 150         /*
 151          * See sbc3r36 section 5.25
 152          * POWER CONDITION 0h START_VALID - process START and LOEJ
 153          */
 154         if (cdb[4] >> 4 & 0xf)
 155                 return TCM_INVALID_CDB_FIELD;
 156 
 157         /*
 158          * See sbc3r36 section 5.25
 159          * LOEJ 0h - nothing to load or unload
 160          * START 1h - we are ready
 161          */
 162         if (!(cdb[4] & 1) || (cdb[4] & 2) || (cdb[4] & 4))
 163                 return TCM_INVALID_CDB_FIELD;
 164 
 165         target_complete_cmd(cmd, SAM_STAT_GOOD);
 166         return 0;
 167 }
 168 
 169 sector_t sbc_get_write_same_sectors(struct se_cmd *cmd)
 170 {
 171         u32 num_blocks;
 172 
 173         if (cmd->t_task_cdb[0] == WRITE_SAME)
 174                 num_blocks = get_unaligned_be16(&cmd->t_task_cdb[7]);
 175         else if (cmd->t_task_cdb[0] == WRITE_SAME_16)
 176                 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[10]);
 177         else /* WRITE_SAME_32 via VARIABLE_LENGTH_CMD */
 178                 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[28]);
 179 
 180         /*
 181          * Use the explicit range when non zero is supplied, otherwise calculate
 182          * the remaining range based on ->get_blocks() - starting LBA.
 183          */
 184         if (num_blocks)
 185                 return num_blocks;
 186 
 187         return cmd->se_dev->transport->get_blocks(cmd->se_dev) -
 188                 cmd->t_task_lba + 1;
 189 }
 190 EXPORT_SYMBOL(sbc_get_write_same_sectors);
 191 
 192 static sense_reason_t
 193 sbc_execute_write_same_unmap(struct se_cmd *cmd)
 194 {
 195         struct sbc_ops *ops = cmd->protocol_data;
 196         sector_t nolb = sbc_get_write_same_sectors(cmd);
 197         sense_reason_t ret;
 198 
 199         if (nolb) {
 200                 ret = ops->execute_unmap(cmd, cmd->t_task_lba, nolb);
 201                 if (ret)
 202                         return ret;
 203         }
 204 
 205         target_complete_cmd(cmd, GOOD);
 206         return 0;
 207 }
 208 
 209 static sense_reason_t
 210 sbc_emulate_noop(struct se_cmd *cmd)
 211 {
 212         target_complete_cmd(cmd, GOOD);
 213         return 0;
 214 }
 215 
 216 static inline u32 sbc_get_size(struct se_cmd *cmd, u32 sectors)
 217 {
 218         return cmd->se_dev->dev_attrib.block_size * sectors;
 219 }
 220 
 221 static inline u32 transport_get_sectors_6(unsigned char *cdb)
 222 {
 223         /*
 224          * Use 8-bit sector value.  SBC-3 says:
 225          *
 226          *   A TRANSFER LENGTH field set to zero specifies that 256
 227          *   logical blocks shall be written.  Any other value
 228          *   specifies the number of logical blocks that shall be
 229          *   written.
 230          */
 231         return cdb[4] ? : 256;
 232 }
 233 
 234 static inline u32 transport_get_sectors_10(unsigned char *cdb)
 235 {
 236         return get_unaligned_be16(&cdb[7]);
 237 }
 238 
 239 static inline u32 transport_get_sectors_12(unsigned char *cdb)
 240 {
 241         return get_unaligned_be32(&cdb[6]);
 242 }
 243 
 244 static inline u32 transport_get_sectors_16(unsigned char *cdb)
 245 {
 246         return get_unaligned_be32(&cdb[10]);
 247 }
 248 
 249 /*
 250  * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
 251  */
 252 static inline u32 transport_get_sectors_32(unsigned char *cdb)
 253 {
 254         return get_unaligned_be32(&cdb[28]);
 255 
 256 }
 257 
 258 static inline u32 transport_lba_21(unsigned char *cdb)
 259 {
 260         return get_unaligned_be24(&cdb[1]) & 0x1fffff;
 261 }
 262 
 263 static inline u32 transport_lba_32(unsigned char *cdb)
 264 {
 265         return get_unaligned_be32(&cdb[2]);
 266 }
 267 
 268 static inline unsigned long long transport_lba_64(unsigned char *cdb)
 269 {
 270         return get_unaligned_be64(&cdb[2]);
 271 }
 272 
 273 /*
 274  * For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs
 275  */
 276 static inline unsigned long long transport_lba_64_ext(unsigned char *cdb)
 277 {
 278         return get_unaligned_be64(&cdb[12]);
 279 }
 280 
 281 static sense_reason_t
 282 sbc_setup_write_same(struct se_cmd *cmd, unsigned char *flags, struct sbc_ops *ops)
 283 {
 284         struct se_device *dev = cmd->se_dev;
 285         sector_t end_lba = dev->transport->get_blocks(dev) + 1;
 286         unsigned int sectors = sbc_get_write_same_sectors(cmd);
 287         sense_reason_t ret;
 288 
 289         if ((flags[0] & 0x04) || (flags[0] & 0x02)) {
 290                 pr_err("WRITE_SAME PBDATA and LBDATA"
 291                         " bits not supported for Block Discard"
 292                         " Emulation\n");
 293                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 294         }
 295         if (sectors > cmd->se_dev->dev_attrib.max_write_same_len) {
 296                 pr_warn("WRITE_SAME sectors: %u exceeds max_write_same_len: %u\n",
 297                         sectors, cmd->se_dev->dev_attrib.max_write_same_len);
 298                 return TCM_INVALID_CDB_FIELD;
 299         }
 300         /*
 301          * Sanity check for LBA wrap and request past end of device.
 302          */
 303         if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
 304             ((cmd->t_task_lba + sectors) > end_lba)) {
 305                 pr_err("WRITE_SAME exceeds last lba %llu (lba %llu, sectors %u)\n",
 306                        (unsigned long long)end_lba, cmd->t_task_lba, sectors);
 307                 return TCM_ADDRESS_OUT_OF_RANGE;
 308         }
 309 
 310         /* We always have ANC_SUP == 0 so setting ANCHOR is always an error */
 311         if (flags[0] & 0x10) {
 312                 pr_warn("WRITE SAME with ANCHOR not supported\n");
 313                 return TCM_INVALID_CDB_FIELD;
 314         }
 315         /*
 316          * Special case for WRITE_SAME w/ UNMAP=1 that ends up getting
 317          * translated into block discard requests within backend code.
 318          */
 319         if (flags[0] & 0x08) {
 320                 if (!ops->execute_unmap)
 321                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 322 
 323                 if (!dev->dev_attrib.emulate_tpws) {
 324                         pr_err("Got WRITE_SAME w/ UNMAP=1, but backend device"
 325                                " has emulate_tpws disabled\n");
 326                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 327                 }
 328                 cmd->execute_cmd = sbc_execute_write_same_unmap;
 329                 return 0;
 330         }
 331         if (!ops->execute_write_same)
 332                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 333 
 334         ret = sbc_check_prot(dev, cmd, &cmd->t_task_cdb[0], sectors, true);
 335         if (ret)
 336                 return ret;
 337 
 338         cmd->execute_cmd = ops->execute_write_same;
 339         return 0;
 340 }
 341 
 342 static sense_reason_t xdreadwrite_callback(struct se_cmd *cmd, bool success,
 343                                            int *post_ret)
 344 {
 345         unsigned char *buf, *addr;
 346         struct scatterlist *sg;
 347         unsigned int offset;
 348         sense_reason_t ret = TCM_NO_SENSE;
 349         int i, count;
 350 
 351         if (!success)
 352                 return 0;
 353 
 354         /*
 355          * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
 356          *
 357          * 1) read the specified logical block(s);
 358          * 2) transfer logical blocks from the data-out buffer;
 359          * 3) XOR the logical blocks transferred from the data-out buffer with
 360          *    the logical blocks read, storing the resulting XOR data in a buffer;
 361          * 4) if the DISABLE WRITE bit is set to zero, then write the logical
 362          *    blocks transferred from the data-out buffer; and
 363          * 5) transfer the resulting XOR data to the data-in buffer.
 364          */
 365         buf = kmalloc(cmd->data_length, GFP_KERNEL);
 366         if (!buf) {
 367                 pr_err("Unable to allocate xor_callback buf\n");
 368                 return TCM_OUT_OF_RESOURCES;
 369         }
 370         /*
 371          * Copy the scatterlist WRITE buffer located at cmd->t_data_sg
 372          * into the locally allocated *buf
 373          */
 374         sg_copy_to_buffer(cmd->t_data_sg,
 375                           cmd->t_data_nents,
 376                           buf,
 377                           cmd->data_length);
 378 
 379         /*
 380          * Now perform the XOR against the BIDI read memory located at
 381          * cmd->t_mem_bidi_list
 382          */
 383 
 384         offset = 0;
 385         for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
 386                 addr = kmap_atomic(sg_page(sg));
 387                 if (!addr) {
 388                         ret = TCM_OUT_OF_RESOURCES;
 389                         goto out;
 390                 }
 391 
 392                 for (i = 0; i < sg->length; i++)
 393                         *(addr + sg->offset + i) ^= *(buf + offset + i);
 394 
 395                 offset += sg->length;
 396                 kunmap_atomic(addr);
 397         }
 398 
 399 out:
 400         kfree(buf);
 401         return ret;
 402 }
 403 
 404 static sense_reason_t
 405 sbc_execute_rw(struct se_cmd *cmd)
 406 {
 407         struct sbc_ops *ops = cmd->protocol_data;
 408 
 409         return ops->execute_rw(cmd, cmd->t_data_sg, cmd->t_data_nents,
 410                                cmd->data_direction);
 411 }
 412 
 413 static sense_reason_t compare_and_write_post(struct se_cmd *cmd, bool success,
 414                                              int *post_ret)
 415 {
 416         struct se_device *dev = cmd->se_dev;
 417         sense_reason_t ret = TCM_NO_SENSE;
 418 
 419         spin_lock_irq(&cmd->t_state_lock);
 420         if (success) {
 421                 *post_ret = 1;
 422 
 423                 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION)
 424                         ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 425         }
 426         spin_unlock_irq(&cmd->t_state_lock);
 427 
 428         /*
 429          * Unlock ->caw_sem originally obtained during sbc_compare_and_write()
 430          * before the original READ I/O submission.
 431          */
 432         up(&dev->caw_sem);
 433 
 434         return ret;
 435 }
 436 
 437 static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool success,
 438                                                  int *post_ret)
 439 {
 440         struct se_device *dev = cmd->se_dev;
 441         struct sg_table write_tbl = { };
 442         struct scatterlist *write_sg, *sg;
 443         unsigned char *buf = NULL, *addr;
 444         struct sg_mapping_iter m;
 445         unsigned int offset = 0, len;
 446         unsigned int nlbas = cmd->t_task_nolb;
 447         unsigned int block_size = dev->dev_attrib.block_size;
 448         unsigned int compare_len = (nlbas * block_size);
 449         sense_reason_t ret = TCM_NO_SENSE;
 450         int rc, i;
 451 
 452         /*
 453          * Handle early failure in transport_generic_request_failure(),
 454          * which will not have taken ->caw_sem yet..
 455          */
 456         if (!success && (!cmd->t_data_sg || !cmd->t_bidi_data_sg))
 457                 return TCM_NO_SENSE;
 458         /*
 459          * Handle special case for zero-length COMPARE_AND_WRITE
 460          */
 461         if (!cmd->data_length)
 462                 goto out;
 463         /*
 464          * Immediately exit + release dev->caw_sem if command has already
 465          * been failed with a non-zero SCSI status.
 466          */
 467         if (cmd->scsi_status) {
 468                 pr_debug("compare_and_write_callback: non zero scsi_status:"
 469                         " 0x%02x\n", cmd->scsi_status);
 470                 *post_ret = 1;
 471                 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION)
 472                         ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 473                 goto out;
 474         }
 475 
 476         buf = kzalloc(cmd->data_length, GFP_KERNEL);
 477         if (!buf) {
 478                 pr_err("Unable to allocate compare_and_write buf\n");
 479                 ret = TCM_OUT_OF_RESOURCES;
 480                 goto out;
 481         }
 482 
 483         if (sg_alloc_table(&write_tbl, cmd->t_data_nents, GFP_KERNEL) < 0) {
 484                 pr_err("Unable to allocate compare_and_write sg\n");
 485                 ret = TCM_OUT_OF_RESOURCES;
 486                 goto out;
 487         }
 488         write_sg = write_tbl.sgl;
 489         /*
 490          * Setup verify and write data payloads from total NumberLBAs.
 491          */
 492         rc = sg_copy_to_buffer(cmd->t_data_sg, cmd->t_data_nents, buf,
 493                                cmd->data_length);
 494         if (!rc) {
 495                 pr_err("sg_copy_to_buffer() failed for compare_and_write\n");
 496                 ret = TCM_OUT_OF_RESOURCES;
 497                 goto out;
 498         }
 499         /*
 500          * Compare against SCSI READ payload against verify payload
 501          */
 502         for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, i) {
 503                 addr = (unsigned char *)kmap_atomic(sg_page(sg));
 504                 if (!addr) {
 505                         ret = TCM_OUT_OF_RESOURCES;
 506                         goto out;
 507                 }
 508 
 509                 len = min(sg->length, compare_len);
 510 
 511                 if (memcmp(addr, buf + offset, len)) {
 512                         pr_warn("Detected MISCOMPARE for addr: %p buf: %p\n",
 513                                 addr, buf + offset);
 514                         kunmap_atomic(addr);
 515                         goto miscompare;
 516                 }
 517                 kunmap_atomic(addr);
 518 
 519                 offset += len;
 520                 compare_len -= len;
 521                 if (!compare_len)
 522                         break;
 523         }
 524 
 525         i = 0;
 526         len = cmd->t_task_nolb * block_size;
 527         sg_miter_start(&m, cmd->t_data_sg, cmd->t_data_nents, SG_MITER_TO_SG);
 528         /*
 529          * Currently assumes NoLB=1 and SGLs are PAGE_SIZE..
 530          */
 531         while (len) {
 532                 sg_miter_next(&m);
 533 
 534                 if (block_size < PAGE_SIZE) {
 535                         sg_set_page(&write_sg[i], m.page, block_size,
 536                                     m.piter.sg->offset + block_size);
 537                 } else {
 538                         sg_miter_next(&m);
 539                         sg_set_page(&write_sg[i], m.page, block_size,
 540                                     m.piter.sg->offset);
 541                 }
 542                 len -= block_size;
 543                 i++;
 544         }
 545         sg_miter_stop(&m);
 546         /*
 547          * Save the original SGL + nents values before updating to new
 548          * assignments, to be released in transport_free_pages() ->
 549          * transport_reset_sgl_orig()
 550          */
 551         cmd->t_data_sg_orig = cmd->t_data_sg;
 552         cmd->t_data_sg = write_sg;
 553         cmd->t_data_nents_orig = cmd->t_data_nents;
 554         cmd->t_data_nents = 1;
 555 
 556         cmd->sam_task_attr = TCM_HEAD_TAG;
 557         cmd->transport_complete_callback = compare_and_write_post;
 558         /*
 559          * Now reset ->execute_cmd() to the normal sbc_execute_rw() handler
 560          * for submitting the adjusted SGL to write instance user-data.
 561          */
 562         cmd->execute_cmd = sbc_execute_rw;
 563 
 564         spin_lock_irq(&cmd->t_state_lock);
 565         cmd->t_state = TRANSPORT_PROCESSING;
 566         cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT;
 567         spin_unlock_irq(&cmd->t_state_lock);
 568 
 569         __target_execute_cmd(cmd, false);
 570 
 571         kfree(buf);
 572         return ret;
 573 
 574 miscompare:
 575         pr_warn("Target/%s: Send MISCOMPARE check condition and sense\n",
 576                 dev->transport->name);
 577         ret = TCM_MISCOMPARE_VERIFY;
 578 out:
 579         /*
 580          * In the MISCOMPARE or failure case, unlock ->caw_sem obtained in
 581          * sbc_compare_and_write() before the original READ I/O submission.
 582          */
 583         up(&dev->caw_sem);
 584         sg_free_table(&write_tbl);
 585         kfree(buf);
 586         return ret;
 587 }
 588 
 589 static sense_reason_t
 590 sbc_compare_and_write(struct se_cmd *cmd)
 591 {
 592         struct sbc_ops *ops = cmd->protocol_data;
 593         struct se_device *dev = cmd->se_dev;
 594         sense_reason_t ret;
 595         int rc;
 596         /*
 597          * Submit the READ first for COMPARE_AND_WRITE to perform the
 598          * comparision using SGLs at cmd->t_bidi_data_sg..
 599          */
 600         rc = down_interruptible(&dev->caw_sem);
 601         if (rc != 0) {
 602                 cmd->transport_complete_callback = NULL;
 603                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 604         }
 605         /*
 606          * Reset cmd->data_length to individual block_size in order to not
 607          * confuse backend drivers that depend on this value matching the
 608          * size of the I/O being submitted.
 609          */
 610         cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size;
 611 
 612         ret = ops->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents,
 613                               DMA_FROM_DEVICE);
 614         if (ret) {
 615                 cmd->transport_complete_callback = NULL;
 616                 up(&dev->caw_sem);
 617                 return ret;
 618         }
 619         /*
 620          * Unlock of dev->caw_sem to occur in compare_and_write_callback()
 621          * upon MISCOMPARE, or in compare_and_write_done() upon completion
 622          * of WRITE instance user-data.
 623          */
 624         return TCM_NO_SENSE;
 625 }
 626 
 627 static int
 628 sbc_set_prot_op_checks(u8 protect, bool fabric_prot, enum target_prot_type prot_type,
 629                        bool is_write, struct se_cmd *cmd)
 630 {
 631         if (is_write) {
 632                 cmd->prot_op = fabric_prot ? TARGET_PROT_DOUT_STRIP :
 633                                protect ? TARGET_PROT_DOUT_PASS :
 634                                TARGET_PROT_DOUT_INSERT;
 635                 switch (protect) {
 636                 case 0x0:
 637                 case 0x3:
 638                         cmd->prot_checks = 0;
 639                         break;
 640                 case 0x1:
 641                 case 0x5:
 642                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 643                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 644                                 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 645                         break;
 646                 case 0x2:
 647                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 648                                 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 649                         break;
 650                 case 0x4:
 651                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 652                         break;
 653                 default:
 654                         pr_err("Unsupported protect field %d\n", protect);
 655                         return -EINVAL;
 656                 }
 657         } else {
 658                 cmd->prot_op = fabric_prot ? TARGET_PROT_DIN_INSERT :
 659                                protect ? TARGET_PROT_DIN_PASS :
 660                                TARGET_PROT_DIN_STRIP;
 661                 switch (protect) {
 662                 case 0x0:
 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 0x3:
 674                         cmd->prot_checks = 0;
 675                         break;
 676                 case 0x4:
 677                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 678                         break;
 679                 default:
 680                         pr_err("Unsupported protect field %d\n", protect);
 681                         return -EINVAL;
 682                 }
 683         }
 684 
 685         return 0;
 686 }
 687 
 688 static sense_reason_t
 689 sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb,
 690                u32 sectors, bool is_write)
 691 {
 692         u8 protect = cdb[1] >> 5;
 693         int sp_ops = cmd->se_sess->sup_prot_ops;
 694         int pi_prot_type = dev->dev_attrib.pi_prot_type;
 695         bool fabric_prot = false;
 696 
 697         if (!cmd->t_prot_sg || !cmd->t_prot_nents) {
 698                 if (unlikely(protect &&
 699                     !dev->dev_attrib.pi_prot_type && !cmd->se_sess->sess_prot_type)) {
 700                         pr_err("CDB contains protect bit, but device + fabric does"
 701                                " not advertise PROTECT=1 feature bit\n");
 702                         return TCM_INVALID_CDB_FIELD;
 703                 }
 704                 if (cmd->prot_pto)
 705                         return TCM_NO_SENSE;
 706         }
 707 
 708         switch (dev->dev_attrib.pi_prot_type) {
 709         case TARGET_DIF_TYPE3_PROT:
 710                 cmd->reftag_seed = 0xffffffff;
 711                 break;
 712         case TARGET_DIF_TYPE2_PROT:
 713                 if (protect)
 714                         return TCM_INVALID_CDB_FIELD;
 715 
 716                 cmd->reftag_seed = cmd->t_task_lba;
 717                 break;
 718         case TARGET_DIF_TYPE1_PROT:
 719                 cmd->reftag_seed = cmd->t_task_lba;
 720                 break;
 721         case TARGET_DIF_TYPE0_PROT:
 722                 /*
 723                  * See if the fabric supports T10-PI, and the session has been
 724                  * configured to allow export PROTECT=1 feature bit with backend
 725                  * devices that don't support T10-PI.
 726                  */
 727                 fabric_prot = is_write ?
 728                               !!(sp_ops & (TARGET_PROT_DOUT_PASS | TARGET_PROT_DOUT_STRIP)) :
 729                               !!(sp_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DIN_INSERT));
 730 
 731                 if (fabric_prot && cmd->se_sess->sess_prot_type) {
 732                         pi_prot_type = cmd->se_sess->sess_prot_type;
 733                         break;
 734                 }
 735                 if (!protect)
 736                         return TCM_NO_SENSE;
 737                 /* Fallthrough */
 738         default:
 739                 pr_err("Unable to determine pi_prot_type for CDB: 0x%02x "
 740                        "PROTECT: 0x%02x\n", cdb[0], protect);
 741                 return TCM_INVALID_CDB_FIELD;
 742         }
 743 
 744         if (sbc_set_prot_op_checks(protect, fabric_prot, pi_prot_type, is_write, cmd))
 745                 return TCM_INVALID_CDB_FIELD;
 746 
 747         cmd->prot_type = pi_prot_type;
 748         cmd->prot_length = dev->prot_length * sectors;
 749 
 750         /**
 751          * In case protection information exists over the wire
 752          * we modify command data length to describe pure data.
 753          * The actual transfer length is data length + protection
 754          * length
 755          **/
 756         if (protect)
 757                 cmd->data_length = sectors * dev->dev_attrib.block_size;
 758 
 759         pr_debug("%s: prot_type=%d, data_length=%d, prot_length=%d "
 760                  "prot_op=%d prot_checks=%d\n",
 761                  __func__, cmd->prot_type, cmd->data_length, cmd->prot_length,
 762                  cmd->prot_op, cmd->prot_checks);
 763 
 764         return TCM_NO_SENSE;
 765 }
 766 
 767 static int
 768 sbc_check_dpofua(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb)
 769 {
 770         if (cdb[1] & 0x10) {
 771                 /* see explanation in spc_emulate_modesense */
 772                 if (!target_check_fua(dev)) {
 773                         pr_err("Got CDB: 0x%02x with DPO bit set, but device"
 774                                " does not advertise support for DPO\n", cdb[0]);
 775                         return -EINVAL;
 776                 }
 777         }
 778         if (cdb[1] & 0x8) {
 779                 if (!target_check_fua(dev)) {
 780                         pr_err("Got CDB: 0x%02x with FUA bit set, but device"
 781                                " does not advertise support for FUA write\n",
 782                                cdb[0]);
 783                         return -EINVAL;
 784                 }
 785                 cmd->se_cmd_flags |= SCF_FUA;
 786         }
 787         return 0;
 788 }
 789 
 790 sense_reason_t
 791 sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 792 {
 793         struct se_device *dev = cmd->se_dev;
 794         unsigned char *cdb = cmd->t_task_cdb;
 795         unsigned int size;
 796         u32 sectors = 0;
 797         sense_reason_t ret;
 798 
 799         cmd->protocol_data = ops;
 800 
 801         switch (cdb[0]) {
 802         case READ_6:
 803                 sectors = transport_get_sectors_6(cdb);
 804                 cmd->t_task_lba = transport_lba_21(cdb);
 805                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 806                 cmd->execute_cmd = sbc_execute_rw;
 807                 break;
 808         case READ_10:
 809                 sectors = transport_get_sectors_10(cdb);
 810                 cmd->t_task_lba = transport_lba_32(cdb);
 811 
 812                 if (sbc_check_dpofua(dev, cmd, cdb))
 813                         return TCM_INVALID_CDB_FIELD;
 814 
 815                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 816                 if (ret)
 817                         return ret;
 818 
 819                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 820                 cmd->execute_cmd = sbc_execute_rw;
 821                 break;
 822         case READ_12:
 823                 sectors = transport_get_sectors_12(cdb);
 824                 cmd->t_task_lba = transport_lba_32(cdb);
 825 
 826                 if (sbc_check_dpofua(dev, cmd, cdb))
 827                         return TCM_INVALID_CDB_FIELD;
 828 
 829                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 830                 if (ret)
 831                         return ret;
 832 
 833                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 834                 cmd->execute_cmd = sbc_execute_rw;
 835                 break;
 836         case READ_16:
 837                 sectors = transport_get_sectors_16(cdb);
 838                 cmd->t_task_lba = transport_lba_64(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 WRITE_6:
 851                 sectors = transport_get_sectors_6(cdb);
 852                 cmd->t_task_lba = transport_lba_21(cdb);
 853                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 854                 cmd->execute_cmd = sbc_execute_rw;
 855                 break;
 856         case WRITE_10:
 857         case WRITE_VERIFY:
 858                 sectors = transport_get_sectors_10(cdb);
 859                 cmd->t_task_lba = transport_lba_32(cdb);
 860 
 861                 if (sbc_check_dpofua(dev, cmd, cdb))
 862                         return TCM_INVALID_CDB_FIELD;
 863 
 864                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 865                 if (ret)
 866                         return ret;
 867 
 868                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 869                 cmd->execute_cmd = sbc_execute_rw;
 870                 break;
 871         case WRITE_12:
 872                 sectors = transport_get_sectors_12(cdb);
 873                 cmd->t_task_lba = transport_lba_32(cdb);
 874 
 875                 if (sbc_check_dpofua(dev, cmd, cdb))
 876                         return TCM_INVALID_CDB_FIELD;
 877 
 878                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 879                 if (ret)
 880                         return ret;
 881 
 882                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 883                 cmd->execute_cmd = sbc_execute_rw;
 884                 break;
 885         case WRITE_16:
 886         case WRITE_VERIFY_16:
 887                 sectors = transport_get_sectors_16(cdb);
 888                 cmd->t_task_lba = transport_lba_64(cdb);
 889 
 890                 if (sbc_check_dpofua(dev, cmd, cdb))
 891                         return TCM_INVALID_CDB_FIELD;
 892 
 893                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 894                 if (ret)
 895                         return ret;
 896 
 897                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 898                 cmd->execute_cmd = sbc_execute_rw;
 899                 break;
 900         case XDWRITEREAD_10:
 901                 if (cmd->data_direction != DMA_TO_DEVICE ||
 902                     !(cmd->se_cmd_flags & SCF_BIDI))
 903                         return TCM_INVALID_CDB_FIELD;
 904                 sectors = transport_get_sectors_10(cdb);
 905 
 906                 if (sbc_check_dpofua(dev, cmd, cdb))
 907                         return TCM_INVALID_CDB_FIELD;
 908 
 909                 cmd->t_task_lba = transport_lba_32(cdb);
 910                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 911 
 912                 /*
 913                  * Setup BIDI XOR callback to be run after I/O completion.
 914                  */
 915                 cmd->execute_cmd = sbc_execute_rw;
 916                 cmd->transport_complete_callback = &xdreadwrite_callback;
 917                 break;
 918         case VARIABLE_LENGTH_CMD:
 919         {
 920                 u16 service_action = get_unaligned_be16(&cdb[8]);
 921                 switch (service_action) {
 922                 case XDWRITEREAD_32:
 923                         sectors = transport_get_sectors_32(cdb);
 924 
 925                         if (sbc_check_dpofua(dev, cmd, cdb))
 926                                 return TCM_INVALID_CDB_FIELD;
 927                         /*
 928                          * Use WRITE_32 and READ_32 opcodes for the emulated
 929                          * XDWRITE_READ_32 logic.
 930                          */
 931                         cmd->t_task_lba = transport_lba_64_ext(cdb);
 932                         cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 933 
 934                         /*
 935                          * Setup BIDI XOR callback to be run during after I/O
 936                          * completion.
 937                          */
 938                         cmd->execute_cmd = sbc_execute_rw;
 939                         cmd->transport_complete_callback = &xdreadwrite_callback;
 940                         break;
 941                 case WRITE_SAME_32:
 942                         sectors = transport_get_sectors_32(cdb);
 943                         if (!sectors) {
 944                                 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
 945                                        " supported\n");
 946                                 return TCM_INVALID_CDB_FIELD;
 947                         }
 948 
 949                         size = sbc_get_size(cmd, 1);
 950                         cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
 951 
 952                         ret = sbc_setup_write_same(cmd, &cdb[10], ops);
 953                         if (ret)
 954                                 return ret;
 955                         break;
 956                 default:
 957                         pr_err("VARIABLE_LENGTH_CMD service action"
 958                                 " 0x%04x not supported\n", service_action);
 959                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 960                 }
 961                 break;
 962         }
 963         case COMPARE_AND_WRITE:
 964                 if (!dev->dev_attrib.emulate_caw) {
 965                         pr_err_ratelimited("se_device %s/%s (vpd_unit_serial %s) reject COMPARE_AND_WRITE\n",
 966                                            dev->se_hba->backend->ops->name,
 967                                            config_item_name(&dev->dev_group.cg_item),
 968                                            dev->t10_wwn.unit_serial);
 969                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 970                 }
 971                 sectors = cdb[13];
 972                 /*
 973                  * Currently enforce COMPARE_AND_WRITE for a single sector
 974                  */
 975                 if (sectors > 1) {
 976                         pr_err("COMPARE_AND_WRITE contains NoLB: %u greater"
 977                                " than 1\n", sectors);
 978                         return TCM_INVALID_CDB_FIELD;
 979                 }
 980                 if (sbc_check_dpofua(dev, cmd, cdb))
 981                         return TCM_INVALID_CDB_FIELD;
 982 
 983                 /*
 984                  * Double size because we have two buffers, note that
 985                  * zero is not an error..
 986                  */
 987                 size = 2 * sbc_get_size(cmd, sectors);
 988                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
 989                 cmd->t_task_nolb = sectors;
 990                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE;
 991                 cmd->execute_cmd = sbc_compare_and_write;
 992                 cmd->transport_complete_callback = compare_and_write_callback;
 993                 break;
 994         case READ_CAPACITY:
 995                 size = READ_CAP_LEN;
 996                 cmd->execute_cmd = sbc_emulate_readcapacity;
 997                 break;
 998         case SERVICE_ACTION_IN_16:
 999                 switch (cmd->t_task_cdb[1] & 0x1f) {
1000                 case SAI_READ_CAPACITY_16:
1001                         cmd->execute_cmd = sbc_emulate_readcapacity_16;
1002                         break;
1003                 case SAI_REPORT_REFERRALS:
1004                         cmd->execute_cmd = target_emulate_report_referrals;
1005                         break;
1006                 default:
1007                         pr_err("Unsupported SA: 0x%02x\n",
1008                                 cmd->t_task_cdb[1] & 0x1f);
1009                         return TCM_INVALID_CDB_FIELD;
1010                 }
1011                 size = get_unaligned_be32(&cdb[10]);
1012                 break;
1013         case SYNCHRONIZE_CACHE:
1014         case SYNCHRONIZE_CACHE_16:
1015                 if (cdb[0] == SYNCHRONIZE_CACHE) {
1016                         sectors = transport_get_sectors_10(cdb);
1017                         cmd->t_task_lba = transport_lba_32(cdb);
1018                 } else {
1019                         sectors = transport_get_sectors_16(cdb);
1020                         cmd->t_task_lba = transport_lba_64(cdb);
1021                 }
1022                 if (ops->execute_sync_cache) {
1023                         cmd->execute_cmd = ops->execute_sync_cache;
1024                         goto check_lba;
1025                 }
1026                 size = 0;
1027                 cmd->execute_cmd = sbc_emulate_noop;
1028                 break;
1029         case UNMAP:
1030                 if (!ops->execute_unmap)
1031                         return TCM_UNSUPPORTED_SCSI_OPCODE;
1032 
1033                 if (!dev->dev_attrib.emulate_tpu) {
1034                         pr_err("Got UNMAP, but backend device has"
1035                                " emulate_tpu disabled\n");
1036                         return TCM_UNSUPPORTED_SCSI_OPCODE;
1037                 }
1038                 size = get_unaligned_be16(&cdb[7]);
1039                 cmd->execute_cmd = sbc_execute_unmap;
1040                 break;
1041         case WRITE_SAME_16:
1042                 sectors = transport_get_sectors_16(cdb);
1043                 if (!sectors) {
1044                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1045                         return TCM_INVALID_CDB_FIELD;
1046                 }
1047 
1048                 size = sbc_get_size(cmd, 1);
1049                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1050 
1051                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1052                 if (ret)
1053                         return ret;
1054                 break;
1055         case WRITE_SAME:
1056                 sectors = transport_get_sectors_10(cdb);
1057                 if (!sectors) {
1058                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1059                         return TCM_INVALID_CDB_FIELD;
1060                 }
1061 
1062                 size = sbc_get_size(cmd, 1);
1063                 cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
1064 
1065                 /*
1066                  * Follow sbcr26 with WRITE_SAME (10) and check for the existence
1067                  * of byte 1 bit 3 UNMAP instead of original reserved field
1068                  */
1069                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1070                 if (ret)
1071                         return ret;
1072                 break;
1073         case VERIFY:
1074         case VERIFY_16:
1075                 size = 0;
1076                 if (cdb[0] == VERIFY) {
1077                         sectors = transport_get_sectors_10(cdb);
1078                         cmd->t_task_lba = transport_lba_32(cdb);
1079                 } else {
1080                         sectors = transport_get_sectors_16(cdb);
1081                         cmd->t_task_lba = transport_lba_64(cdb);
1082                 }
1083                 cmd->execute_cmd = sbc_emulate_noop;
1084                 goto check_lba;
1085         case REZERO_UNIT:
1086         case SEEK_6:
1087         case SEEK_10:
1088                 /*
1089                  * There are still clients out there which use these old SCSI-2
1090                  * commands. This mainly happens when running VMs with legacy
1091                  * guest systems, connected via SCSI command pass-through to
1092                  * iSCSI targets. Make them happy and return status GOOD.
1093                  */
1094                 size = 0;
1095                 cmd->execute_cmd = sbc_emulate_noop;
1096                 break;
1097         case START_STOP:
1098                 size = 0;
1099                 cmd->execute_cmd = sbc_emulate_startstop;
1100                 break;
1101         default:
1102                 ret = spc_parse_cdb(cmd, &size);
1103                 if (ret)
1104                         return ret;
1105         }
1106 
1107         /* reject any command that we don't have a handler for */
1108         if (!cmd->execute_cmd)
1109                 return TCM_UNSUPPORTED_SCSI_OPCODE;
1110 
1111         if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1112                 unsigned long long end_lba;
1113 check_lba:
1114                 end_lba = dev->transport->get_blocks(dev) + 1;
1115                 if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
1116                     ((cmd->t_task_lba + sectors) > end_lba)) {
1117                         pr_err("cmd exceeds last lba %llu "
1118                                 "(lba %llu, sectors %u)\n",
1119                                 end_lba, cmd->t_task_lba, sectors);
1120                         return TCM_ADDRESS_OUT_OF_RANGE;
1121                 }
1122 
1123                 if (!(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE))
1124                         size = sbc_get_size(cmd, sectors);
1125         }
1126 
1127         return target_cmd_size_check(cmd, size);
1128 }
1129 EXPORT_SYMBOL(sbc_parse_cdb);
1130 
1131 u32 sbc_get_device_type(struct se_device *dev)
1132 {
1133         return TYPE_DISK;
1134 }
1135 EXPORT_SYMBOL(sbc_get_device_type);
1136 
1137 static sense_reason_t
1138 sbc_execute_unmap(struct se_cmd *cmd)
1139 {
1140         struct sbc_ops *ops = cmd->protocol_data;
1141         struct se_device *dev = cmd->se_dev;
1142         unsigned char *buf, *ptr = NULL;
1143         sector_t lba;
1144         int size;
1145         u32 range;
1146         sense_reason_t ret = 0;
1147         int dl, bd_dl;
1148 
1149         /* We never set ANC_SUP */
1150         if (cmd->t_task_cdb[1])
1151                 return TCM_INVALID_CDB_FIELD;
1152 
1153         if (cmd->data_length == 0) {
1154                 target_complete_cmd(cmd, SAM_STAT_GOOD);
1155                 return 0;
1156         }
1157 
1158         if (cmd->data_length < 8) {
1159                 pr_warn("UNMAP parameter list length %u too small\n",
1160                         cmd->data_length);
1161                 return TCM_PARAMETER_LIST_LENGTH_ERROR;
1162         }
1163 
1164         buf = transport_kmap_data_sg(cmd);
1165         if (!buf)
1166                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1167 
1168         dl = get_unaligned_be16(&buf[0]);
1169         bd_dl = get_unaligned_be16(&buf[2]);
1170 
1171         size = cmd->data_length - 8;
1172         if (bd_dl > size)
1173                 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
1174                         cmd->data_length, bd_dl);
1175         else
1176                 size = bd_dl;
1177 
1178         if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
1179                 ret = TCM_INVALID_PARAMETER_LIST;
1180                 goto err;
1181         }
1182 
1183         /* First UNMAP block descriptor starts at 8 byte offset */
1184         ptr = &buf[8];
1185         pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
1186                 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
1187 
1188         while (size >= 16) {
1189                 lba = get_unaligned_be64(&ptr[0]);
1190                 range = get_unaligned_be32(&ptr[8]);
1191                 pr_debug("UNMAP: Using lba: %llu and range: %u\n",
1192                                  (unsigned long long)lba, range);
1193 
1194                 if (range > dev->dev_attrib.max_unmap_lba_count) {
1195                         ret = TCM_INVALID_PARAMETER_LIST;
1196                         goto err;
1197                 }
1198 
1199                 if (lba + range > dev->transport->get_blocks(dev) + 1) {
1200                         ret = TCM_ADDRESS_OUT_OF_RANGE;
1201                         goto err;
1202                 }
1203 
1204                 if (range) {
1205                         ret = ops->execute_unmap(cmd, lba, range);
1206                         if (ret)
1207                                 goto err;
1208                 }
1209 
1210                 ptr += 16;
1211                 size -= 16;
1212         }
1213 
1214 err:
1215         transport_kunmap_data_sg(cmd);
1216         if (!ret)
1217                 target_complete_cmd(cmd, GOOD);
1218         return ret;
1219 }
1220 
1221 void
1222 sbc_dif_generate(struct se_cmd *cmd)
1223 {
1224         struct se_device *dev = cmd->se_dev;
1225         struct t10_pi_tuple *sdt;
1226         struct scatterlist *dsg = cmd->t_data_sg, *psg;
1227         sector_t sector = cmd->t_task_lba;
1228         void *daddr, *paddr;
1229         int i, j, offset = 0;
1230         unsigned int block_size = dev->dev_attrib.block_size;
1231 
1232         for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1233                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1234                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1235 
1236                 for (j = 0; j < psg->length;
1237                                 j += sizeof(*sdt)) {
1238                         __u16 crc;
1239                         unsigned int avail;
1240 
1241                         if (offset >= dsg->length) {
1242                                 offset -= dsg->length;
1243                                 kunmap_atomic(daddr - dsg->offset);
1244                                 dsg = sg_next(dsg);
1245                                 if (!dsg) {
1246                                         kunmap_atomic(paddr - psg->offset);
1247                                         return;
1248                                 }
1249                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1250                         }
1251 
1252                         sdt = paddr + j;
1253                         avail = min(block_size, dsg->length - offset);
1254                         crc = crc_t10dif(daddr + offset, avail);
1255                         if (avail < block_size) {
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                                 offset = block_size - avail;
1264                                 crc = crc_t10dif_update(crc, daddr, offset);
1265                         } else {
1266                                 offset += block_size;
1267                         }
1268 
1269                         sdt->guard_tag = cpu_to_be16(crc);
1270                         if (cmd->prot_type == TARGET_DIF_TYPE1_PROT)
1271                                 sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
1272                         sdt->app_tag = 0;
1273 
1274                         pr_debug("DIF %s INSERT sector: %llu guard_tag: 0x%04x"
1275                                  " app_tag: 0x%04x ref_tag: %u\n",
1276                                  (cmd->data_direction == DMA_TO_DEVICE) ?
1277                                  "WRITE" : "READ", (unsigned long long)sector,
1278                                  sdt->guard_tag, sdt->app_tag,
1279                                  be32_to_cpu(sdt->ref_tag));
1280 
1281                         sector++;
1282                 }
1283 
1284                 kunmap_atomic(daddr - dsg->offset);
1285                 kunmap_atomic(paddr - psg->offset);
1286         }
1287 }
1288 
1289 static sense_reason_t
1290 sbc_dif_v1_verify(struct se_cmd *cmd, struct t10_pi_tuple *sdt,
1291                   __u16 crc, sector_t sector, unsigned int ei_lba)
1292 {
1293         __be16 csum;
1294 
1295         if (!(cmd->prot_checks & TARGET_DIF_CHECK_GUARD))
1296                 goto check_ref;
1297 
1298         csum = cpu_to_be16(crc);
1299 
1300         if (sdt->guard_tag != csum) {
1301                 pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x"
1302                         " csum 0x%04x\n", (unsigned long long)sector,
1303                         be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
1304                 return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
1305         }
1306 
1307 check_ref:
1308         if (!(cmd->prot_checks & TARGET_DIF_CHECK_REFTAG))
1309                 return 0;
1310 
1311         if (cmd->prot_type == TARGET_DIF_TYPE1_PROT &&
1312             be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
1313                 pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x"
1314                        " sector MSB: 0x%08x\n", (unsigned long long)sector,
1315                        be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff));
1316                 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1317         }
1318 
1319         if (cmd->prot_type == TARGET_DIF_TYPE2_PROT &&
1320             be32_to_cpu(sdt->ref_tag) != ei_lba) {
1321                 pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x"
1322                        " ei_lba: 0x%08x\n", (unsigned long long)sector,
1323                         be32_to_cpu(sdt->ref_tag), ei_lba);
1324                 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1325         }
1326 
1327         return 0;
1328 }
1329 
1330 void sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read,
1331                        struct scatterlist *sg, int sg_off)
1332 {
1333         struct se_device *dev = cmd->se_dev;
1334         struct scatterlist *psg;
1335         void *paddr, *addr;
1336         unsigned int i, len, left;
1337         unsigned int offset = sg_off;
1338 
1339         if (!sg)
1340                 return;
1341 
1342         left = sectors * dev->prot_length;
1343 
1344         for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1345                 unsigned int psg_len, copied = 0;
1346 
1347                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1348                 psg_len = min(left, psg->length);
1349                 while (psg_len) {
1350                         len = min(psg_len, sg->length - offset);
1351                         addr = kmap_atomic(sg_page(sg)) + sg->offset + offset;
1352 
1353                         if (read)
1354                                 memcpy(paddr + copied, addr, len);
1355                         else
1356                                 memcpy(addr, paddr + copied, len);
1357 
1358                         left -= len;
1359                         offset += len;
1360                         copied += len;
1361                         psg_len -= len;
1362 
1363                         kunmap_atomic(addr - sg->offset - offset);
1364 
1365                         if (offset >= sg->length) {
1366                                 sg = sg_next(sg);
1367                                 offset = 0;
1368                         }
1369                 }
1370                 kunmap_atomic(paddr - psg->offset);
1371         }
1372 }
1373 EXPORT_SYMBOL(sbc_dif_copy_prot);
1374 
1375 sense_reason_t
1376 sbc_dif_verify(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1377                unsigned int ei_lba, struct scatterlist *psg, int psg_off)
1378 {
1379         struct se_device *dev = cmd->se_dev;
1380         struct t10_pi_tuple *sdt;
1381         struct scatterlist *dsg = cmd->t_data_sg;
1382         sector_t sector = start;
1383         void *daddr, *paddr;
1384         int i;
1385         sense_reason_t rc;
1386         int dsg_off = 0;
1387         unsigned int block_size = dev->dev_attrib.block_size;
1388 
1389         for (; psg && sector < start + sectors; psg = sg_next(psg)) {
1390                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1391                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1392 
1393                 for (i = psg_off; i < psg->length &&
1394                                 sector < start + sectors;
1395                                 i += sizeof(*sdt)) {
1396                         __u16 crc;
1397                         unsigned int avail;
1398 
1399                         if (dsg_off >= dsg->length) {
1400                                 dsg_off -= dsg->length;
1401                                 kunmap_atomic(daddr - dsg->offset);
1402                                 dsg = sg_next(dsg);
1403                                 if (!dsg) {
1404                                         kunmap_atomic(paddr - psg->offset);
1405                                         return 0;
1406                                 }
1407                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1408                         }
1409 
1410                         sdt = paddr + i;
1411 
1412                         pr_debug("DIF READ sector: %llu guard_tag: 0x%04x"
1413                                  " app_tag: 0x%04x ref_tag: %u\n",
1414                                  (unsigned long long)sector, sdt->guard_tag,
1415                                  sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1416 
1417                         if (sdt->app_tag == T10_PI_APP_ESCAPE) {
1418                                 dsg_off += block_size;
1419                                 goto next;
1420                         }
1421 
1422                         avail = min(block_size, dsg->length - dsg_off);
1423                         crc = crc_t10dif(daddr + dsg_off, avail);
1424                         if (avail < block_size) {
1425                                 kunmap_atomic(daddr - dsg->offset);
1426                                 dsg = sg_next(dsg);
1427                                 if (!dsg) {
1428                                         kunmap_atomic(paddr - psg->offset);
1429                                         return 0;
1430                                 }
1431                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1432                                 dsg_off = block_size - avail;
1433                                 crc = crc_t10dif_update(crc, daddr, dsg_off);
1434                         } else {
1435                                 dsg_off += block_size;
1436                         }
1437 
1438                         rc = sbc_dif_v1_verify(cmd, sdt, crc, sector, ei_lba);
1439                         if (rc) {
1440                                 kunmap_atomic(daddr - dsg->offset);
1441                                 kunmap_atomic(paddr - psg->offset);
1442                                 cmd->bad_sector = sector;
1443                                 return rc;
1444                         }
1445 next:
1446                         sector++;
1447                         ei_lba++;
1448                 }
1449 
1450                 psg_off = 0;
1451                 kunmap_atomic(daddr - dsg->offset);
1452                 kunmap_atomic(paddr - psg->offset);
1453         }
1454 
1455         return 0;
1456 }
1457 EXPORT_SYMBOL(sbc_dif_verify);
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/target/target_core_sbc.c

DEFINITIONS
