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, SAM_STAT_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, SAM_STAT_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, SAM_STAT_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, SAM_STAT_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 & 0x04) || (flags & 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 & 0x10) { 312 pr_warn("WRITE SAME with ANCHOR not supported\n"); 313 return TCM_INVALID_CDB_FIELD; 314 } 315 316 if (flags & 0x01) { 317 pr_warn("WRITE SAME with NDOB not supported\n"); 318 return TCM_INVALID_CDB_FIELD; 319 } 320 321 /* 322 * Special case for WRITE_SAME w/ UNMAP=1 that ends up getting 323 * translated into block discard requests within backend code. 324 */ 325 if (flags & 0x08) { 326 if (!ops->execute_unmap) 327 return TCM_UNSUPPORTED_SCSI_OPCODE; 328 329 if (!dev->dev_attrib.emulate_tpws) { 330 pr_err("Got WRITE_SAME w/ UNMAP=1, but backend device" 331 " has emulate_tpws disabled\n"); 332 return TCM_UNSUPPORTED_SCSI_OPCODE; 333 } 334 cmd->execute_cmd = sbc_execute_write_same_unmap; 335 return 0; 336 } 337 if (!ops->execute_write_same) 338 return TCM_UNSUPPORTED_SCSI_OPCODE; 339 340 ret = sbc_check_prot(dev, cmd, flags >> 5, sectors, true); 341 if (ret) 342 return ret; 343 344 cmd->execute_cmd = ops->execute_write_same; 345 return 0; 346 } 347 348 static sense_reason_t 349 sbc_execute_rw(struct se_cmd *cmd) 350 { 351 struct sbc_ops *ops = cmd->protocol_data; 352 353 return ops->execute_rw(cmd, cmd->t_data_sg, cmd->t_data_nents, 354 cmd->data_direction); 355 } 356 357 static sense_reason_t compare_and_write_post(struct se_cmd *cmd, bool success, 358 int *post_ret) 359 { 360 struct se_device *dev = cmd->se_dev; 361 sense_reason_t ret = TCM_NO_SENSE; 362 363 spin_lock_irq(&cmd->t_state_lock); 364 if (success) { 365 *post_ret = 1; 366 367 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION) 368 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 369 } 370 spin_unlock_irq(&cmd->t_state_lock); 371 372 /* 373 * Unlock ->caw_sem originally obtained during sbc_compare_and_write() 374 * before the original READ I/O submission. 375 */ 376 up(&dev->caw_sem); 377 378 return ret; 379 } 380 381 /* 382 * compare @cmp_len bytes of @read_sgl with @cmp_sgl. On miscompare, fill 383 * @miscmp_off and return TCM_MISCOMPARE_VERIFY. 384 */ 385 static sense_reason_t 386 compare_and_write_do_cmp(struct scatterlist *read_sgl, unsigned int read_nents, 387 struct scatterlist *cmp_sgl, unsigned int cmp_nents, 388 unsigned int cmp_len, unsigned int *miscmp_off) 389 { 390 unsigned char *buf = NULL; 391 struct scatterlist *sg; 392 sense_reason_t ret; 393 unsigned int offset; 394 size_t rc; 395 int sg_cnt; 396 397 buf = kzalloc(cmp_len, GFP_KERNEL); 398 if (!buf) { 399 ret = TCM_OUT_OF_RESOURCES; 400 goto out; 401 } 402 403 rc = sg_copy_to_buffer(cmp_sgl, cmp_nents, buf, cmp_len); 404 if (!rc) { 405 pr_err("sg_copy_to_buffer() failed for compare_and_write\n"); 406 ret = TCM_OUT_OF_RESOURCES; 407 goto out; 408 } 409 /* 410 * Compare SCSI READ payload against verify payload 411 */ 412 offset = 0; 413 ret = TCM_NO_SENSE; 414 for_each_sg(read_sgl, sg, read_nents, sg_cnt) { 415 unsigned int len = min(sg->length, cmp_len); 416 unsigned char *addr = kmap_atomic(sg_page(sg)); 417 418 if (memcmp(addr, buf + offset, len)) { 419 unsigned int i; 420 421 for (i = 0; i < len && addr[i] == buf[offset + i]; i++) 422 ; 423 *miscmp_off = offset + i; 424 pr_warn("Detected MISCOMPARE at offset %u\n", 425 *miscmp_off); 426 ret = TCM_MISCOMPARE_VERIFY; 427 } 428 kunmap_atomic(addr); 429 if (ret != TCM_NO_SENSE) 430 goto out; 431 432 offset += len; 433 cmp_len -= len; 434 if (!cmp_len) 435 break; 436 } 437 pr_debug("COMPARE AND WRITE read data matches compare data\n"); 438 out: 439 kfree(buf); 440 return ret; 441 } 442 443 static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool success, 444 int *post_ret) 445 { 446 struct se_device *dev = cmd->se_dev; 447 struct sg_table write_tbl = { }; 448 struct scatterlist *write_sg; 449 struct sg_mapping_iter m; 450 unsigned int len; 451 unsigned int block_size = dev->dev_attrib.block_size; 452 unsigned int compare_len = (cmd->t_task_nolb * block_size); 453 unsigned int miscmp_off = 0; 454 sense_reason_t ret = TCM_NO_SENSE; 455 int i; 456 457 /* 458 * Handle early failure in transport_generic_request_failure(), 459 * which will not have taken ->caw_sem yet.. 460 */ 461 if (!success && (!cmd->t_data_sg || !cmd->t_bidi_data_sg)) 462 return TCM_NO_SENSE; 463 /* 464 * Handle special case for zero-length COMPARE_AND_WRITE 465 */ 466 if (!cmd->data_length) 467 goto out; 468 /* 469 * Immediately exit + release dev->caw_sem if command has already 470 * been failed with a non-zero SCSI status. 471 */ 472 if (cmd->scsi_status) { 473 pr_debug("compare_and_write_callback: non zero scsi_status:" 474 " 0x%02x\n", cmd->scsi_status); 475 *post_ret = 1; 476 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION) 477 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 478 goto out; 479 } 480 481 ret = compare_and_write_do_cmp(cmd->t_bidi_data_sg, 482 cmd->t_bidi_data_nents, 483 cmd->t_data_sg, 484 cmd->t_data_nents, 485 compare_len, 486 &miscmp_off); 487 if (ret == TCM_MISCOMPARE_VERIFY) { 488 /* 489 * SBC-4 r15: 5.3 COMPARE AND WRITE command 490 * In the sense data (see 4.18 and SPC-5) the offset from the 491 * start of the Data-Out Buffer to the first byte of data that 492 * was not equal shall be reported in the INFORMATION field. 493 */ 494 cmd->sense_info = miscmp_off; 495 goto out; 496 } else if (ret) 497 goto out; 498 499 if (sg_alloc_table(&write_tbl, cmd->t_data_nents, GFP_KERNEL) < 0) { 500 pr_err("Unable to allocate compare_and_write sg\n"); 501 ret = TCM_OUT_OF_RESOURCES; 502 goto out; 503 } 504 write_sg = write_tbl.sgl; 505 506 i = 0; 507 len = compare_len; 508 sg_miter_start(&m, cmd->t_data_sg, cmd->t_data_nents, SG_MITER_TO_SG); 509 /* 510 * Currently assumes NoLB=1 and SGLs are PAGE_SIZE.. 511 */ 512 while (len) { 513 sg_miter_next(&m); 514 515 if (block_size < PAGE_SIZE) { 516 sg_set_page(&write_sg[i], m.page, block_size, 517 m.piter.sg->offset + block_size); 518 } else { 519 sg_miter_next(&m); 520 sg_set_page(&write_sg[i], m.page, block_size, 521 m.piter.sg->offset); 522 } 523 len -= block_size; 524 i++; 525 } 526 sg_miter_stop(&m); 527 /* 528 * Save the original SGL + nents values before updating to new 529 * assignments, to be released in transport_free_pages() -> 530 * transport_reset_sgl_orig() 531 */ 532 cmd->t_data_sg_orig = cmd->t_data_sg; 533 cmd->t_data_sg = write_sg; 534 cmd->t_data_nents_orig = cmd->t_data_nents; 535 cmd->t_data_nents = 1; 536 537 cmd->sam_task_attr = TCM_HEAD_TAG; 538 cmd->transport_complete_callback = compare_and_write_post; 539 /* 540 * Now reset ->execute_cmd() to the normal sbc_execute_rw() handler 541 * for submitting the adjusted SGL to write instance user-data. 542 */ 543 cmd->execute_cmd = sbc_execute_rw; 544 545 spin_lock_irq(&cmd->t_state_lock); 546 cmd->t_state = TRANSPORT_PROCESSING; 547 cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT; 548 spin_unlock_irq(&cmd->t_state_lock); 549 550 __target_execute_cmd(cmd, false); 551 552 return ret; 553 554 out: 555 /* 556 * In the MISCOMPARE or failure case, unlock ->caw_sem obtained in 557 * sbc_compare_and_write() before the original READ I/O submission. 558 */ 559 up(&dev->caw_sem); 560 sg_free_table(&write_tbl); 561 return ret; 562 } 563 564 static sense_reason_t 565 sbc_compare_and_write(struct se_cmd *cmd) 566 { 567 struct sbc_ops *ops = cmd->protocol_data; 568 struct se_device *dev = cmd->se_dev; 569 sense_reason_t ret; 570 int rc; 571 /* 572 * Submit the READ first for COMPARE_AND_WRITE to perform the 573 * comparision using SGLs at cmd->t_bidi_data_sg.. 574 */ 575 rc = down_interruptible(&dev->caw_sem); 576 if (rc != 0) { 577 cmd->transport_complete_callback = NULL; 578 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 579 } 580 /* 581 * Reset cmd->data_length to individual block_size in order to not 582 * confuse backend drivers that depend on this value matching the 583 * size of the I/O being submitted. 584 */ 585 cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size; 586 587 ret = ops->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents, 588 DMA_FROM_DEVICE); 589 if (ret) { 590 cmd->transport_complete_callback = NULL; 591 up(&dev->caw_sem); 592 return ret; 593 } 594 /* 595 * Unlock of dev->caw_sem to occur in compare_and_write_callback() 596 * upon MISCOMPARE, or in compare_and_write_done() upon completion 597 * of WRITE instance user-data. 598 */ 599 return TCM_NO_SENSE; 600 } 601 602 static int 603 sbc_set_prot_op_checks(u8 protect, bool fabric_prot, enum target_prot_type prot_type, 604 bool is_write, struct se_cmd *cmd) 605 { 606 if (is_write) { 607 cmd->prot_op = fabric_prot ? TARGET_PROT_DOUT_STRIP : 608 protect ? TARGET_PROT_DOUT_PASS : 609 TARGET_PROT_DOUT_INSERT; 610 switch (protect) { 611 case 0x0: 612 case 0x3: 613 cmd->prot_checks = 0; 614 break; 615 case 0x1: 616 case 0x5: 617 cmd->prot_checks = TARGET_DIF_CHECK_GUARD; 618 if (prot_type == TARGET_DIF_TYPE1_PROT) 619 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG; 620 break; 621 case 0x2: 622 if (prot_type == TARGET_DIF_TYPE1_PROT) 623 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG; 624 break; 625 case 0x4: 626 cmd->prot_checks = TARGET_DIF_CHECK_GUARD; 627 break; 628 default: 629 pr_err("Unsupported protect field %d\n", protect); 630 return -EINVAL; 631 } 632 } else { 633 cmd->prot_op = fabric_prot ? TARGET_PROT_DIN_INSERT : 634 protect ? TARGET_PROT_DIN_PASS : 635 TARGET_PROT_DIN_STRIP; 636 switch (protect) { 637 case 0x0: 638 case 0x1: 639 case 0x5: 640 cmd->prot_checks = TARGET_DIF_CHECK_GUARD; 641 if (prot_type == TARGET_DIF_TYPE1_PROT) 642 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG; 643 break; 644 case 0x2: 645 if (prot_type == TARGET_DIF_TYPE1_PROT) 646 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG; 647 break; 648 case 0x3: 649 cmd->prot_checks = 0; 650 break; 651 case 0x4: 652 cmd->prot_checks = TARGET_DIF_CHECK_GUARD; 653 break; 654 default: 655 pr_err("Unsupported protect field %d\n", protect); 656 return -EINVAL; 657 } 658 } 659 660 return 0; 661 } 662 663 static sense_reason_t 664 sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char protect, 665 u32 sectors, bool is_write) 666 { 667 int sp_ops = cmd->se_sess->sup_prot_ops; 668 int pi_prot_type = dev->dev_attrib.pi_prot_type; 669 bool fabric_prot = false; 670 671 if (!cmd->t_prot_sg || !cmd->t_prot_nents) { 672 if (unlikely(protect && 673 !dev->dev_attrib.pi_prot_type && !cmd->se_sess->sess_prot_type)) { 674 pr_err("CDB contains protect bit, but device + fabric does" 675 " not advertise PROTECT=1 feature bit\n"); 676 return TCM_INVALID_CDB_FIELD; 677 } 678 if (cmd->prot_pto) 679 return TCM_NO_SENSE; 680 } 681 682 switch (dev->dev_attrib.pi_prot_type) { 683 case TARGET_DIF_TYPE3_PROT: 684 cmd->reftag_seed = 0xffffffff; 685 break; 686 case TARGET_DIF_TYPE2_PROT: 687 if (protect) 688 return TCM_INVALID_CDB_FIELD; 689 690 cmd->reftag_seed = cmd->t_task_lba; 691 break; 692 case TARGET_DIF_TYPE1_PROT: 693 cmd->reftag_seed = cmd->t_task_lba; 694 break; 695 case TARGET_DIF_TYPE0_PROT: 696 /* 697 * See if the fabric supports T10-PI, and the session has been 698 * configured to allow export PROTECT=1 feature bit with backend 699 * devices that don't support T10-PI. 700 */ 701 fabric_prot = is_write ? 702 !!(sp_ops & (TARGET_PROT_DOUT_PASS | TARGET_PROT_DOUT_STRIP)) : 703 !!(sp_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DIN_INSERT)); 704 705 if (fabric_prot && cmd->se_sess->sess_prot_type) { 706 pi_prot_type = cmd->se_sess->sess_prot_type; 707 break; 708 } 709 if (!protect) 710 return TCM_NO_SENSE; 711 fallthrough; 712 default: 713 pr_err("Unable to determine pi_prot_type for CDB: 0x%02x " 714 "PROTECT: 0x%02x\n", cmd->t_task_cdb[0], protect); 715 return TCM_INVALID_CDB_FIELD; 716 } 717 718 if (sbc_set_prot_op_checks(protect, fabric_prot, pi_prot_type, is_write, cmd)) 719 return TCM_INVALID_CDB_FIELD; 720 721 cmd->prot_type = pi_prot_type; 722 cmd->prot_length = dev->prot_length * sectors; 723 724 /** 725 * In case protection information exists over the wire 726 * we modify command data length to describe pure data. 727 * The actual transfer length is data length + protection 728 * length 729 **/ 730 if (protect) 731 cmd->data_length = sectors * dev->dev_attrib.block_size; 732 733 pr_debug("%s: prot_type=%d, data_length=%d, prot_length=%d " 734 "prot_op=%d prot_checks=%d\n", 735 __func__, cmd->prot_type, cmd->data_length, cmd->prot_length, 736 cmd->prot_op, cmd->prot_checks); 737 738 return TCM_NO_SENSE; 739 } 740 741 static int 742 sbc_check_dpofua(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb) 743 { 744 if (cdb[1] & 0x10) { 745 /* see explanation in spc_emulate_modesense */ 746 if (!target_check_fua(dev)) { 747 pr_err("Got CDB: 0x%02x with DPO bit set, but device" 748 " does not advertise support for DPO\n", cdb[0]); 749 return -EINVAL; 750 } 751 } 752 if (cdb[1] & 0x8) { 753 if (!target_check_fua(dev)) { 754 pr_err("Got CDB: 0x%02x with FUA bit set, but device" 755 " does not advertise support for FUA write\n", 756 cdb[0]); 757 return -EINVAL; 758 } 759 cmd->se_cmd_flags |= SCF_FUA; 760 } 761 return 0; 762 } 763 764 sense_reason_t 765 sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops) 766 { 767 struct se_device *dev = cmd->se_dev; 768 unsigned char *cdb = cmd->t_task_cdb; 769 unsigned int size; 770 u32 sectors = 0; 771 sense_reason_t ret; 772 773 cmd->protocol_data = ops; 774 775 switch (cdb[0]) { 776 case READ_6: 777 sectors = transport_get_sectors_6(cdb); 778 cmd->t_task_lba = transport_lba_21(cdb); 779 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 780 cmd->execute_cmd = sbc_execute_rw; 781 break; 782 case READ_10: 783 sectors = transport_get_sectors_10(cdb); 784 cmd->t_task_lba = transport_lba_32(cdb); 785 786 if (sbc_check_dpofua(dev, cmd, cdb)) 787 return TCM_INVALID_CDB_FIELD; 788 789 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false); 790 if (ret) 791 return ret; 792 793 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 794 cmd->execute_cmd = sbc_execute_rw; 795 break; 796 case READ_12: 797 sectors = transport_get_sectors_12(cdb); 798 cmd->t_task_lba = transport_lba_32(cdb); 799 800 if (sbc_check_dpofua(dev, cmd, cdb)) 801 return TCM_INVALID_CDB_FIELD; 802 803 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false); 804 if (ret) 805 return ret; 806 807 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 808 cmd->execute_cmd = sbc_execute_rw; 809 break; 810 case READ_16: 811 sectors = transport_get_sectors_16(cdb); 812 cmd->t_task_lba = transport_lba_64(cdb); 813 814 if (sbc_check_dpofua(dev, cmd, cdb)) 815 return TCM_INVALID_CDB_FIELD; 816 817 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false); 818 if (ret) 819 return ret; 820 821 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 822 cmd->execute_cmd = sbc_execute_rw; 823 break; 824 case WRITE_6: 825 sectors = transport_get_sectors_6(cdb); 826 cmd->t_task_lba = transport_lba_21(cdb); 827 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 828 cmd->execute_cmd = sbc_execute_rw; 829 break; 830 case WRITE_10: 831 case WRITE_VERIFY: 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[1] >> 5, sectors, true); 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 WRITE_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[1] >> 5, sectors, true); 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 WRITE_16: 860 case WRITE_VERIFY_16: 861 sectors = transport_get_sectors_16(cdb); 862 cmd->t_task_lba = transport_lba_64(cdb); 863 864 if (sbc_check_dpofua(dev, cmd, cdb)) 865 return TCM_INVALID_CDB_FIELD; 866 867 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, true); 868 if (ret) 869 return ret; 870 871 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 872 cmd->execute_cmd = sbc_execute_rw; 873 break; 874 case VARIABLE_LENGTH_CMD: 875 { 876 u16 service_action = get_unaligned_be16(&cdb[8]); 877 switch (service_action) { 878 case WRITE_SAME_32: 879 sectors = transport_get_sectors_32(cdb); 880 if (!sectors) { 881 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not" 882 " supported\n"); 883 return TCM_INVALID_CDB_FIELD; 884 } 885 886 size = sbc_get_size(cmd, 1); 887 cmd->t_task_lba = get_unaligned_be64(&cdb[12]); 888 889 ret = sbc_setup_write_same(cmd, cdb[10], ops); 890 if (ret) 891 return ret; 892 break; 893 default: 894 pr_err("VARIABLE_LENGTH_CMD service action" 895 " 0x%04x not supported\n", service_action); 896 return TCM_UNSUPPORTED_SCSI_OPCODE; 897 } 898 break; 899 } 900 case COMPARE_AND_WRITE: 901 if (!dev->dev_attrib.emulate_caw) { 902 pr_err_ratelimited("se_device %s/%s (vpd_unit_serial %s) reject COMPARE_AND_WRITE\n", 903 dev->se_hba->backend->ops->name, 904 config_item_name(&dev->dev_group.cg_item), 905 dev->t10_wwn.unit_serial); 906 return TCM_UNSUPPORTED_SCSI_OPCODE; 907 } 908 sectors = cdb[13]; 909 /* 910 * Currently enforce COMPARE_AND_WRITE for a single sector 911 */ 912 if (sectors > 1) { 913 pr_err("COMPARE_AND_WRITE contains NoLB: %u greater" 914 " than 1\n", sectors); 915 return TCM_INVALID_CDB_FIELD; 916 } 917 if (sbc_check_dpofua(dev, cmd, cdb)) 918 return TCM_INVALID_CDB_FIELD; 919 920 /* 921 * Double size because we have two buffers, note that 922 * zero is not an error.. 923 */ 924 size = 2 * sbc_get_size(cmd, sectors); 925 cmd->t_task_lba = get_unaligned_be64(&cdb[2]); 926 cmd->t_task_nolb = sectors; 927 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE; 928 cmd->execute_cmd = sbc_compare_and_write; 929 cmd->transport_complete_callback = compare_and_write_callback; 930 break; 931 case READ_CAPACITY: 932 size = READ_CAP_LEN; 933 cmd->execute_cmd = sbc_emulate_readcapacity; 934 break; 935 case SERVICE_ACTION_IN_16: 936 switch (cmd->t_task_cdb[1] & 0x1f) { 937 case SAI_READ_CAPACITY_16: 938 cmd->execute_cmd = sbc_emulate_readcapacity_16; 939 break; 940 case SAI_REPORT_REFERRALS: 941 cmd->execute_cmd = target_emulate_report_referrals; 942 break; 943 default: 944 pr_err("Unsupported SA: 0x%02x\n", 945 cmd->t_task_cdb[1] & 0x1f); 946 return TCM_INVALID_CDB_FIELD; 947 } 948 size = get_unaligned_be32(&cdb[10]); 949 break; 950 case SYNCHRONIZE_CACHE: 951 case SYNCHRONIZE_CACHE_16: 952 if (cdb[0] == SYNCHRONIZE_CACHE) { 953 sectors = transport_get_sectors_10(cdb); 954 cmd->t_task_lba = transport_lba_32(cdb); 955 } else { 956 sectors = transport_get_sectors_16(cdb); 957 cmd->t_task_lba = transport_lba_64(cdb); 958 } 959 if (ops->execute_sync_cache) { 960 cmd->execute_cmd = ops->execute_sync_cache; 961 goto check_lba; 962 } 963 size = 0; 964 cmd->execute_cmd = sbc_emulate_noop; 965 break; 966 case UNMAP: 967 if (!ops->execute_unmap) 968 return TCM_UNSUPPORTED_SCSI_OPCODE; 969 970 if (!dev->dev_attrib.emulate_tpu) { 971 pr_err("Got UNMAP, but backend device has" 972 " emulate_tpu disabled\n"); 973 return TCM_UNSUPPORTED_SCSI_OPCODE; 974 } 975 size = get_unaligned_be16(&cdb[7]); 976 cmd->execute_cmd = sbc_execute_unmap; 977 break; 978 case WRITE_SAME_16: 979 sectors = transport_get_sectors_16(cdb); 980 if (!sectors) { 981 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n"); 982 return TCM_INVALID_CDB_FIELD; 983 } 984 985 size = sbc_get_size(cmd, 1); 986 cmd->t_task_lba = get_unaligned_be64(&cdb[2]); 987 988 ret = sbc_setup_write_same(cmd, cdb[1], ops); 989 if (ret) 990 return ret; 991 break; 992 case WRITE_SAME: 993 sectors = transport_get_sectors_10(cdb); 994 if (!sectors) { 995 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n"); 996 return TCM_INVALID_CDB_FIELD; 997 } 998 999 size = sbc_get_size(cmd, 1); 1000 cmd->t_task_lba = get_unaligned_be32(&cdb[2]); 1001 1002 /* 1003 * Follow sbcr26 with WRITE_SAME (10) and check for the existence 1004 * of byte 1 bit 3 UNMAP instead of original reserved field 1005 */ 1006 ret = sbc_setup_write_same(cmd, cdb[1], ops); 1007 if (ret) 1008 return ret; 1009 break; 1010 case VERIFY: 1011 case VERIFY_16: 1012 size = 0; 1013 if (cdb[0] == VERIFY) { 1014 sectors = transport_get_sectors_10(cdb); 1015 cmd->t_task_lba = transport_lba_32(cdb); 1016 } else { 1017 sectors = transport_get_sectors_16(cdb); 1018 cmd->t_task_lba = transport_lba_64(cdb); 1019 } 1020 cmd->execute_cmd = sbc_emulate_noop; 1021 goto check_lba; 1022 case REZERO_UNIT: 1023 case SEEK_6: 1024 case SEEK_10: 1025 /* 1026 * There are still clients out there which use these old SCSI-2 1027 * commands. This mainly happens when running VMs with legacy 1028 * guest systems, connected via SCSI command pass-through to 1029 * iSCSI targets. Make them happy and return status GOOD. 1030 */ 1031 size = 0; 1032 cmd->execute_cmd = sbc_emulate_noop; 1033 break; 1034 case START_STOP: 1035 size = 0; 1036 cmd->execute_cmd = sbc_emulate_startstop; 1037 break; 1038 default: 1039 ret = spc_parse_cdb(cmd, &size); 1040 if (ret) 1041 return ret; 1042 } 1043 1044 /* reject any command that we don't have a handler for */ 1045 if (!cmd->execute_cmd) 1046 return TCM_UNSUPPORTED_SCSI_OPCODE; 1047 1048 if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) { 1049 unsigned long long end_lba; 1050 check_lba: 1051 end_lba = dev->transport->get_blocks(dev) + 1; 1052 if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) || 1053 ((cmd->t_task_lba + sectors) > end_lba)) { 1054 pr_err("cmd exceeds last lba %llu " 1055 "(lba %llu, sectors %u)\n", 1056 end_lba, cmd->t_task_lba, sectors); 1057 return TCM_ADDRESS_OUT_OF_RANGE; 1058 } 1059 1060 if (!(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) 1061 size = sbc_get_size(cmd, sectors); 1062 } 1063 1064 return target_cmd_size_check(cmd, size); 1065 } 1066 EXPORT_SYMBOL(sbc_parse_cdb); 1067 1068 u32 sbc_get_device_type(struct se_device *dev) 1069 { 1070 return TYPE_DISK; 1071 } 1072 EXPORT_SYMBOL(sbc_get_device_type); 1073 1074 static sense_reason_t 1075 sbc_execute_unmap(struct se_cmd *cmd) 1076 { 1077 struct sbc_ops *ops = cmd->protocol_data; 1078 struct se_device *dev = cmd->se_dev; 1079 unsigned char *buf, *ptr = NULL; 1080 sector_t lba; 1081 int size; 1082 u32 range; 1083 sense_reason_t ret = 0; 1084 int dl, bd_dl; 1085 1086 /* We never set ANC_SUP */ 1087 if (cmd->t_task_cdb[1]) 1088 return TCM_INVALID_CDB_FIELD; 1089 1090 if (cmd->data_length == 0) { 1091 target_complete_cmd(cmd, SAM_STAT_GOOD); 1092 return 0; 1093 } 1094 1095 if (cmd->data_length < 8) { 1096 pr_warn("UNMAP parameter list length %u too small\n", 1097 cmd->data_length); 1098 return TCM_PARAMETER_LIST_LENGTH_ERROR; 1099 } 1100 1101 buf = transport_kmap_data_sg(cmd); 1102 if (!buf) 1103 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 1104 1105 dl = get_unaligned_be16(&buf[0]); 1106 bd_dl = get_unaligned_be16(&buf[2]); 1107 1108 size = cmd->data_length - 8; 1109 if (bd_dl > size) 1110 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n", 1111 cmd->data_length, bd_dl); 1112 else 1113 size = bd_dl; 1114 1115 if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) { 1116 ret = TCM_INVALID_PARAMETER_LIST; 1117 goto err; 1118 } 1119 1120 /* First UNMAP block descriptor starts at 8 byte offset */ 1121 ptr = &buf[8]; 1122 pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u" 1123 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr); 1124 1125 while (size >= 16) { 1126 lba = get_unaligned_be64(&ptr[0]); 1127 range = get_unaligned_be32(&ptr[8]); 1128 pr_debug("UNMAP: Using lba: %llu and range: %u\n", 1129 (unsigned long long)lba, range); 1130 1131 if (range > dev->dev_attrib.max_unmap_lba_count) { 1132 ret = TCM_INVALID_PARAMETER_LIST; 1133 goto err; 1134 } 1135 1136 if (lba + range > dev->transport->get_blocks(dev) + 1) { 1137 ret = TCM_ADDRESS_OUT_OF_RANGE; 1138 goto err; 1139 } 1140 1141 if (range) { 1142 ret = ops->execute_unmap(cmd, lba, range); 1143 if (ret) 1144 goto err; 1145 } 1146 1147 ptr += 16; 1148 size -= 16; 1149 } 1150 1151 err: 1152 transport_kunmap_data_sg(cmd); 1153 if (!ret) 1154 target_complete_cmd(cmd, SAM_STAT_GOOD); 1155 return ret; 1156 } 1157 1158 void 1159 sbc_dif_generate(struct se_cmd *cmd) 1160 { 1161 struct se_device *dev = cmd->se_dev; 1162 struct t10_pi_tuple *sdt; 1163 struct scatterlist *dsg = cmd->t_data_sg, *psg; 1164 sector_t sector = cmd->t_task_lba; 1165 void *daddr, *paddr; 1166 int i, j, offset = 0; 1167 unsigned int block_size = dev->dev_attrib.block_size; 1168 1169 for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) { 1170 paddr = kmap_atomic(sg_page(psg)) + psg->offset; 1171 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; 1172 1173 for (j = 0; j < psg->length; 1174 j += sizeof(*sdt)) { 1175 __u16 crc; 1176 unsigned int avail; 1177 1178 if (offset >= dsg->length) { 1179 offset -= dsg->length; 1180 kunmap_atomic(daddr - dsg->offset); 1181 dsg = sg_next(dsg); 1182 if (!dsg) { 1183 kunmap_atomic(paddr - psg->offset); 1184 return; 1185 } 1186 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; 1187 } 1188 1189 sdt = paddr + j; 1190 avail = min(block_size, dsg->length - offset); 1191 crc = crc_t10dif(daddr + offset, avail); 1192 if (avail < block_size) { 1193 kunmap_atomic(daddr - dsg->offset); 1194 dsg = sg_next(dsg); 1195 if (!dsg) { 1196 kunmap_atomic(paddr - psg->offset); 1197 return; 1198 } 1199 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; 1200 offset = block_size - avail; 1201 crc = crc_t10dif_update(crc, daddr, offset); 1202 } else { 1203 offset += block_size; 1204 } 1205 1206 sdt->guard_tag = cpu_to_be16(crc); 1207 if (cmd->prot_type == TARGET_DIF_TYPE1_PROT) 1208 sdt->ref_tag = cpu_to_be32(sector & 0xffffffff); 1209 sdt->app_tag = 0; 1210 1211 pr_debug("DIF %s INSERT sector: %llu guard_tag: 0x%04x" 1212 " app_tag: 0x%04x ref_tag: %u\n", 1213 (cmd->data_direction == DMA_TO_DEVICE) ? 1214 "WRITE" : "READ", (unsigned long long)sector, 1215 sdt->guard_tag, sdt->app_tag, 1216 be32_to_cpu(sdt->ref_tag)); 1217 1218 sector++; 1219 } 1220 1221 kunmap_atomic(daddr - dsg->offset); 1222 kunmap_atomic(paddr - psg->offset); 1223 } 1224 } 1225 1226 static sense_reason_t 1227 sbc_dif_v1_verify(struct se_cmd *cmd, struct t10_pi_tuple *sdt, 1228 __u16 crc, sector_t sector, unsigned int ei_lba) 1229 { 1230 __be16 csum; 1231 1232 if (!(cmd->prot_checks & TARGET_DIF_CHECK_GUARD)) 1233 goto check_ref; 1234 1235 csum = cpu_to_be16(crc); 1236 1237 if (sdt->guard_tag != csum) { 1238 pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x" 1239 " csum 0x%04x\n", (unsigned long long)sector, 1240 be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum)); 1241 return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED; 1242 } 1243 1244 check_ref: 1245 if (!(cmd->prot_checks & TARGET_DIF_CHECK_REFTAG)) 1246 return 0; 1247 1248 if (cmd->prot_type == TARGET_DIF_TYPE1_PROT && 1249 be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) { 1250 pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x" 1251 " sector MSB: 0x%08x\n", (unsigned long long)sector, 1252 be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff)); 1253 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED; 1254 } 1255 1256 if (cmd->prot_type == TARGET_DIF_TYPE2_PROT && 1257 be32_to_cpu(sdt->ref_tag) != ei_lba) { 1258 pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x" 1259 " ei_lba: 0x%08x\n", (unsigned long long)sector, 1260 be32_to_cpu(sdt->ref_tag), ei_lba); 1261 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED; 1262 } 1263 1264 return 0; 1265 } 1266 1267 void sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read, 1268 struct scatterlist *sg, int sg_off) 1269 { 1270 struct se_device *dev = cmd->se_dev; 1271 struct scatterlist *psg; 1272 void *paddr, *addr; 1273 unsigned int i, len, left; 1274 unsigned int offset = sg_off; 1275 1276 if (!sg) 1277 return; 1278 1279 left = sectors * dev->prot_length; 1280 1281 for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) { 1282 unsigned int psg_len, copied = 0; 1283 1284 paddr = kmap_atomic(sg_page(psg)) + psg->offset; 1285 psg_len = min(left, psg->length); 1286 while (psg_len) { 1287 len = min(psg_len, sg->length - offset); 1288 addr = kmap_atomic(sg_page(sg)) + sg->offset + offset; 1289 1290 if (read) 1291 memcpy(paddr + copied, addr, len); 1292 else 1293 memcpy(addr, paddr + copied, len); 1294 1295 left -= len; 1296 offset += len; 1297 copied += len; 1298 psg_len -= len; 1299 1300 kunmap_atomic(addr - sg->offset - offset); 1301 1302 if (offset >= sg->length) { 1303 sg = sg_next(sg); 1304 offset = 0; 1305 } 1306 } 1307 kunmap_atomic(paddr - psg->offset); 1308 } 1309 } 1310 EXPORT_SYMBOL(sbc_dif_copy_prot); 1311 1312 sense_reason_t 1313 sbc_dif_verify(struct se_cmd *cmd, sector_t start, unsigned int sectors, 1314 unsigned int ei_lba, struct scatterlist *psg, int psg_off) 1315 { 1316 struct se_device *dev = cmd->se_dev; 1317 struct t10_pi_tuple *sdt; 1318 struct scatterlist *dsg = cmd->t_data_sg; 1319 sector_t sector = start; 1320 void *daddr, *paddr; 1321 int i; 1322 sense_reason_t rc; 1323 int dsg_off = 0; 1324 unsigned int block_size = dev->dev_attrib.block_size; 1325 1326 for (; psg && sector < start + sectors; psg = sg_next(psg)) { 1327 paddr = kmap_atomic(sg_page(psg)) + psg->offset; 1328 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; 1329 1330 for (i = psg_off; i < psg->length && 1331 sector < start + sectors; 1332 i += sizeof(*sdt)) { 1333 __u16 crc; 1334 unsigned int avail; 1335 1336 if (dsg_off >= dsg->length) { 1337 dsg_off -= dsg->length; 1338 kunmap_atomic(daddr - dsg->offset); 1339 dsg = sg_next(dsg); 1340 if (!dsg) { 1341 kunmap_atomic(paddr - psg->offset); 1342 return 0; 1343 } 1344 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; 1345 } 1346 1347 sdt = paddr + i; 1348 1349 pr_debug("DIF READ sector: %llu guard_tag: 0x%04x" 1350 " app_tag: 0x%04x ref_tag: %u\n", 1351 (unsigned long long)sector, sdt->guard_tag, 1352 sdt->app_tag, be32_to_cpu(sdt->ref_tag)); 1353 1354 if (sdt->app_tag == T10_PI_APP_ESCAPE) { 1355 dsg_off += block_size; 1356 goto next; 1357 } 1358 1359 avail = min(block_size, dsg->length - dsg_off); 1360 crc = crc_t10dif(daddr + dsg_off, avail); 1361 if (avail < block_size) { 1362 kunmap_atomic(daddr - dsg->offset); 1363 dsg = sg_next(dsg); 1364 if (!dsg) { 1365 kunmap_atomic(paddr - psg->offset); 1366 return 0; 1367 } 1368 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; 1369 dsg_off = block_size - avail; 1370 crc = crc_t10dif_update(crc, daddr, dsg_off); 1371 } else { 1372 dsg_off += block_size; 1373 } 1374 1375 rc = sbc_dif_v1_verify(cmd, sdt, crc, sector, ei_lba); 1376 if (rc) { 1377 kunmap_atomic(daddr - dsg->offset); 1378 kunmap_atomic(paddr - psg->offset); 1379 cmd->sense_info = sector; 1380 return rc; 1381 } 1382 next: 1383 sector++; 1384 ei_lba++; 1385 } 1386 1387 psg_off = 0; 1388 kunmap_atomic(daddr - dsg->offset); 1389 kunmap_atomic(paddr - psg->offset); 1390 } 1391 1392 return 0; 1393 } 1394 EXPORT_SYMBOL(sbc_dif_verify); 1395