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 * 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 & 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, flags >> 5, 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 343 sbc_execute_rw(struct se_cmd *cmd) 344 { 345 struct sbc_ops *ops = cmd->protocol_data; 346 347 return ops->execute_rw(cmd, cmd->t_data_sg, cmd->t_data_nents, 348 cmd->data_direction); 349 } 350 351 static sense_reason_t compare_and_write_post(struct se_cmd *cmd, bool success, 352 int *post_ret) 353 { 354 struct se_device *dev = cmd->se_dev; 355 sense_reason_t ret = TCM_NO_SENSE; 356 357 spin_lock_irq(&cmd->t_state_lock); 358 if (success) { 359 *post_ret = 1; 360 361 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION) 362 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 363 } 364 spin_unlock_irq(&cmd->t_state_lock); 365 366 /* 367 * Unlock ->caw_sem originally obtained during sbc_compare_and_write() 368 * before the original READ I/O submission. 369 */ 370 up(&dev->caw_sem); 371 372 return ret; 373 } 374 375 /* 376 * compare @cmp_len bytes of @read_sgl with @cmp_sgl. On miscompare, fill 377 * @miscmp_off and return TCM_MISCOMPARE_VERIFY. 378 */ 379 static sense_reason_t 380 compare_and_write_do_cmp(struct scatterlist *read_sgl, unsigned int read_nents, 381 struct scatterlist *cmp_sgl, unsigned int cmp_nents, 382 unsigned int cmp_len, unsigned int *miscmp_off) 383 { 384 unsigned char *buf = NULL; 385 struct scatterlist *sg; 386 sense_reason_t ret; 387 unsigned int offset; 388 size_t rc; 389 int sg_cnt; 390 391 buf = kzalloc(cmp_len, GFP_KERNEL); 392 if (!buf) { 393 ret = TCM_OUT_OF_RESOURCES; 394 goto out; 395 } 396 397 rc = sg_copy_to_buffer(cmp_sgl, cmp_nents, buf, cmp_len); 398 if (!rc) { 399 pr_err("sg_copy_to_buffer() failed for compare_and_write\n"); 400 ret = TCM_OUT_OF_RESOURCES; 401 goto out; 402 } 403 /* 404 * Compare SCSI READ payload against verify payload 405 */ 406 offset = 0; 407 ret = TCM_NO_SENSE; 408 for_each_sg(read_sgl, sg, read_nents, sg_cnt) { 409 unsigned int len = min(sg->length, cmp_len); 410 unsigned char *addr = kmap_atomic(sg_page(sg)); 411 412 if (memcmp(addr, buf + offset, len)) { 413 unsigned int i; 414 415 for (i = 0; i < len && addr[i] == buf[offset + i]; i++) 416 ; 417 *miscmp_off = offset + i; 418 pr_warn("Detected MISCOMPARE at offset %u\n", 419 *miscmp_off); 420 ret = TCM_MISCOMPARE_VERIFY; 421 } 422 kunmap_atomic(addr); 423 if (ret != TCM_NO_SENSE) 424 goto out; 425 426 offset += len; 427 cmp_len -= len; 428 if (!cmp_len) 429 break; 430 } 431 pr_debug("COMPARE AND WRITE read data matches compare data\n"); 432 out: 433 kfree(buf); 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; 443 struct sg_mapping_iter m; 444 unsigned int len; 445 unsigned int block_size = dev->dev_attrib.block_size; 446 unsigned int compare_len = (cmd->t_task_nolb * block_size); 447 unsigned int miscmp_off = 0; 448 sense_reason_t ret = TCM_NO_SENSE; 449 int i; 450 451 /* 452 * Handle early failure in transport_generic_request_failure(), 453 * which will not have taken ->caw_sem yet.. 454 */ 455 if (!success && (!cmd->t_data_sg || !cmd->t_bidi_data_sg)) 456 return TCM_NO_SENSE; 457 /* 458 * Handle special case for zero-length COMPARE_AND_WRITE 459 */ 460 if (!cmd->data_length) 461 goto out; 462 /* 463 * Immediately exit + release dev->caw_sem if command has already 464 * been failed with a non-zero SCSI status. 465 */ 466 if (cmd->scsi_status) { 467 pr_debug("compare_and_write_callback: non zero scsi_status:" 468 " 0x%02x\n", cmd->scsi_status); 469 *post_ret = 1; 470 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION) 471 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 472 goto out; 473 } 474 475 ret = compare_and_write_do_cmp(cmd->t_bidi_data_sg, 476 cmd->t_bidi_data_nents, 477 cmd->t_data_sg, 478 cmd->t_data_nents, 479 compare_len, 480 &miscmp_off); 481 if (ret == TCM_MISCOMPARE_VERIFY) { 482 /* 483 * SBC-4 r15: 5.3 COMPARE AND WRITE command 484 * In the sense data (see 4.18 and SPC-5) the offset from the 485 * start of the Data-Out Buffer to the first byte of data that 486 * was not equal shall be reported in the INFORMATION field. 487 */ 488 cmd->sense_info = miscmp_off; 489 goto out; 490 } else if (ret) 491 goto out; 492 493 if (sg_alloc_table(&write_tbl, cmd->t_data_nents, GFP_KERNEL) < 0) { 494 pr_err("Unable to allocate compare_and_write sg\n"); 495 ret = TCM_OUT_OF_RESOURCES; 496 goto out; 497 } 498 write_sg = write_tbl.sgl; 499 500 i = 0; 501 len = compare_len; 502 sg_miter_start(&m, cmd->t_data_sg, cmd->t_data_nents, SG_MITER_TO_SG); 503 /* 504 * Currently assumes NoLB=1 and SGLs are PAGE_SIZE.. 505 */ 506 while (len) { 507 sg_miter_next(&m); 508 509 if (block_size < PAGE_SIZE) { 510 sg_set_page(&write_sg[i], m.page, block_size, 511 m.piter.sg->offset + block_size); 512 } else { 513 sg_miter_next(&m); 514 sg_set_page(&write_sg[i], m.page, block_size, 515 m.piter.sg->offset); 516 } 517 len -= block_size; 518 i++; 519 } 520 sg_miter_stop(&m); 521 /* 522 * Save the original SGL + nents values before updating to new 523 * assignments, to be released in transport_free_pages() -> 524 * transport_reset_sgl_orig() 525 */ 526 cmd->t_data_sg_orig = cmd->t_data_sg; 527 cmd->t_data_sg = write_sg; 528 cmd->t_data_nents_orig = cmd->t_data_nents; 529 cmd->t_data_nents = 1; 530 531 cmd->sam_task_attr = TCM_HEAD_TAG; 532 cmd->transport_complete_callback = compare_and_write_post; 533 /* 534 * Now reset ->execute_cmd() to the normal sbc_execute_rw() handler 535 * for submitting the adjusted SGL to write instance user-data. 536 */ 537 cmd->execute_cmd = sbc_execute_rw; 538 539 spin_lock_irq(&cmd->t_state_lock); 540 cmd->t_state = TRANSPORT_PROCESSING; 541 cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT; 542 spin_unlock_irq(&cmd->t_state_lock); 543 544 __target_execute_cmd(cmd, false); 545 546 return ret; 547 548 out: 549 /* 550 * In the MISCOMPARE or failure case, unlock ->caw_sem obtained in 551 * sbc_compare_and_write() before the original READ I/O submission. 552 */ 553 up(&dev->caw_sem); 554 sg_free_table(&write_tbl); 555 return ret; 556 } 557 558 static sense_reason_t 559 sbc_compare_and_write(struct se_cmd *cmd) 560 { 561 struct sbc_ops *ops = cmd->protocol_data; 562 struct se_device *dev = cmd->se_dev; 563 sense_reason_t ret; 564 int rc; 565 /* 566 * Submit the READ first for COMPARE_AND_WRITE to perform the 567 * comparision using SGLs at cmd->t_bidi_data_sg.. 568 */ 569 rc = down_interruptible(&dev->caw_sem); 570 if (rc != 0) { 571 cmd->transport_complete_callback = NULL; 572 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 573 } 574 /* 575 * Reset cmd->data_length to individual block_size in order to not 576 * confuse backend drivers that depend on this value matching the 577 * size of the I/O being submitted. 578 */ 579 cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size; 580 581 ret = ops->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents, 582 DMA_FROM_DEVICE); 583 if (ret) { 584 cmd->transport_complete_callback = NULL; 585 up(&dev->caw_sem); 586 return ret; 587 } 588 /* 589 * Unlock of dev->caw_sem to occur in compare_and_write_callback() 590 * upon MISCOMPARE, or in compare_and_write_done() upon completion 591 * of WRITE instance user-data. 592 */ 593 return TCM_NO_SENSE; 594 } 595 596 static int 597 sbc_set_prot_op_checks(u8 protect, bool fabric_prot, enum target_prot_type prot_type, 598 bool is_write, struct se_cmd *cmd) 599 { 600 if (is_write) { 601 cmd->prot_op = fabric_prot ? TARGET_PROT_DOUT_STRIP : 602 protect ? TARGET_PROT_DOUT_PASS : 603 TARGET_PROT_DOUT_INSERT; 604 switch (protect) { 605 case 0x0: 606 case 0x3: 607 cmd->prot_checks = 0; 608 break; 609 case 0x1: 610 case 0x5: 611 cmd->prot_checks = TARGET_DIF_CHECK_GUARD; 612 if (prot_type == TARGET_DIF_TYPE1_PROT) 613 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG; 614 break; 615 case 0x2: 616 if (prot_type == TARGET_DIF_TYPE1_PROT) 617 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG; 618 break; 619 case 0x4: 620 cmd->prot_checks = TARGET_DIF_CHECK_GUARD; 621 break; 622 default: 623 pr_err("Unsupported protect field %d\n", protect); 624 return -EINVAL; 625 } 626 } else { 627 cmd->prot_op = fabric_prot ? TARGET_PROT_DIN_INSERT : 628 protect ? TARGET_PROT_DIN_PASS : 629 TARGET_PROT_DIN_STRIP; 630 switch (protect) { 631 case 0x0: 632 case 0x1: 633 case 0x5: 634 cmd->prot_checks = TARGET_DIF_CHECK_GUARD; 635 if (prot_type == TARGET_DIF_TYPE1_PROT) 636 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG; 637 break; 638 case 0x2: 639 if (prot_type == TARGET_DIF_TYPE1_PROT) 640 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG; 641 break; 642 case 0x3: 643 cmd->prot_checks = 0; 644 break; 645 case 0x4: 646 cmd->prot_checks = TARGET_DIF_CHECK_GUARD; 647 break; 648 default: 649 pr_err("Unsupported protect field %d\n", protect); 650 return -EINVAL; 651 } 652 } 653 654 return 0; 655 } 656 657 static sense_reason_t 658 sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char protect, 659 u32 sectors, bool is_write) 660 { 661 int sp_ops = cmd->se_sess->sup_prot_ops; 662 int pi_prot_type = dev->dev_attrib.pi_prot_type; 663 bool fabric_prot = false; 664 665 if (!cmd->t_prot_sg || !cmd->t_prot_nents) { 666 if (unlikely(protect && 667 !dev->dev_attrib.pi_prot_type && !cmd->se_sess->sess_prot_type)) { 668 pr_err("CDB contains protect bit, but device + fabric does" 669 " not advertise PROTECT=1 feature bit\n"); 670 return TCM_INVALID_CDB_FIELD; 671 } 672 if (cmd->prot_pto) 673 return TCM_NO_SENSE; 674 } 675 676 switch (dev->dev_attrib.pi_prot_type) { 677 case TARGET_DIF_TYPE3_PROT: 678 cmd->reftag_seed = 0xffffffff; 679 break; 680 case TARGET_DIF_TYPE2_PROT: 681 if (protect) 682 return TCM_INVALID_CDB_FIELD; 683 684 cmd->reftag_seed = cmd->t_task_lba; 685 break; 686 case TARGET_DIF_TYPE1_PROT: 687 cmd->reftag_seed = cmd->t_task_lba; 688 break; 689 case TARGET_DIF_TYPE0_PROT: 690 /* 691 * See if the fabric supports T10-PI, and the session has been 692 * configured to allow export PROTECT=1 feature bit with backend 693 * devices that don't support T10-PI. 694 */ 695 fabric_prot = is_write ? 696 !!(sp_ops & (TARGET_PROT_DOUT_PASS | TARGET_PROT_DOUT_STRIP)) : 697 !!(sp_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DIN_INSERT)); 698 699 if (fabric_prot && cmd->se_sess->sess_prot_type) { 700 pi_prot_type = cmd->se_sess->sess_prot_type; 701 break; 702 } 703 if (!protect) 704 return TCM_NO_SENSE; 705 fallthrough; 706 default: 707 pr_err("Unable to determine pi_prot_type for CDB: 0x%02x " 708 "PROTECT: 0x%02x\n", cmd->t_task_cdb[0], protect); 709 return TCM_INVALID_CDB_FIELD; 710 } 711 712 if (sbc_set_prot_op_checks(protect, fabric_prot, pi_prot_type, is_write, cmd)) 713 return TCM_INVALID_CDB_FIELD; 714 715 cmd->prot_type = pi_prot_type; 716 cmd->prot_length = dev->prot_length * sectors; 717 718 /** 719 * In case protection information exists over the wire 720 * we modify command data length to describe pure data. 721 * The actual transfer length is data length + protection 722 * length 723 **/ 724 if (protect) 725 cmd->data_length = sectors * dev->dev_attrib.block_size; 726 727 pr_debug("%s: prot_type=%d, data_length=%d, prot_length=%d " 728 "prot_op=%d prot_checks=%d\n", 729 __func__, cmd->prot_type, cmd->data_length, cmd->prot_length, 730 cmd->prot_op, cmd->prot_checks); 731 732 return TCM_NO_SENSE; 733 } 734 735 static int 736 sbc_check_dpofua(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb) 737 { 738 if (cdb[1] & 0x10) { 739 /* see explanation in spc_emulate_modesense */ 740 if (!target_check_fua(dev)) { 741 pr_err("Got CDB: 0x%02x with DPO bit set, but device" 742 " does not advertise support for DPO\n", cdb[0]); 743 return -EINVAL; 744 } 745 } 746 if (cdb[1] & 0x8) { 747 if (!target_check_fua(dev)) { 748 pr_err("Got CDB: 0x%02x with FUA bit set, but device" 749 " does not advertise support for FUA write\n", 750 cdb[0]); 751 return -EINVAL; 752 } 753 cmd->se_cmd_flags |= SCF_FUA; 754 } 755 return 0; 756 } 757 758 sense_reason_t 759 sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops) 760 { 761 struct se_device *dev = cmd->se_dev; 762 unsigned char *cdb = cmd->t_task_cdb; 763 unsigned int size; 764 u32 sectors = 0; 765 sense_reason_t ret; 766 767 cmd->protocol_data = ops; 768 769 switch (cdb[0]) { 770 case READ_6: 771 sectors = transport_get_sectors_6(cdb); 772 cmd->t_task_lba = transport_lba_21(cdb); 773 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 774 cmd->execute_cmd = sbc_execute_rw; 775 break; 776 case READ_10: 777 sectors = transport_get_sectors_10(cdb); 778 cmd->t_task_lba = transport_lba_32(cdb); 779 780 if (sbc_check_dpofua(dev, cmd, cdb)) 781 return TCM_INVALID_CDB_FIELD; 782 783 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false); 784 if (ret) 785 return ret; 786 787 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 788 cmd->execute_cmd = sbc_execute_rw; 789 break; 790 case READ_12: 791 sectors = transport_get_sectors_12(cdb); 792 cmd->t_task_lba = transport_lba_32(cdb); 793 794 if (sbc_check_dpofua(dev, cmd, cdb)) 795 return TCM_INVALID_CDB_FIELD; 796 797 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false); 798 if (ret) 799 return ret; 800 801 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 802 cmd->execute_cmd = sbc_execute_rw; 803 break; 804 case READ_16: 805 sectors = transport_get_sectors_16(cdb); 806 cmd->t_task_lba = transport_lba_64(cdb); 807 808 if (sbc_check_dpofua(dev, cmd, cdb)) 809 return TCM_INVALID_CDB_FIELD; 810 811 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false); 812 if (ret) 813 return ret; 814 815 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 816 cmd->execute_cmd = sbc_execute_rw; 817 break; 818 case WRITE_6: 819 sectors = transport_get_sectors_6(cdb); 820 cmd->t_task_lba = transport_lba_21(cdb); 821 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 822 cmd->execute_cmd = sbc_execute_rw; 823 break; 824 case WRITE_10: 825 case WRITE_VERIFY: 826 sectors = transport_get_sectors_10(cdb); 827 cmd->t_task_lba = transport_lba_32(cdb); 828 829 if (sbc_check_dpofua(dev, cmd, cdb)) 830 return TCM_INVALID_CDB_FIELD; 831 832 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, true); 833 if (ret) 834 return ret; 835 836 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 837 cmd->execute_cmd = sbc_execute_rw; 838 break; 839 case WRITE_12: 840 sectors = transport_get_sectors_12(cdb); 841 cmd->t_task_lba = transport_lba_32(cdb); 842 843 if (sbc_check_dpofua(dev, cmd, cdb)) 844 return TCM_INVALID_CDB_FIELD; 845 846 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, true); 847 if (ret) 848 return ret; 849 850 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 851 cmd->execute_cmd = sbc_execute_rw; 852 break; 853 case WRITE_16: 854 case WRITE_VERIFY_16: 855 sectors = transport_get_sectors_16(cdb); 856 cmd->t_task_lba = transport_lba_64(cdb); 857 858 if (sbc_check_dpofua(dev, cmd, cdb)) 859 return TCM_INVALID_CDB_FIELD; 860 861 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, true); 862 if (ret) 863 return ret; 864 865 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 866 cmd->execute_cmd = sbc_execute_rw; 867 break; 868 case VARIABLE_LENGTH_CMD: 869 { 870 u16 service_action = get_unaligned_be16(&cdb[8]); 871 switch (service_action) { 872 case WRITE_SAME_32: 873 sectors = transport_get_sectors_32(cdb); 874 if (!sectors) { 875 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not" 876 " supported\n"); 877 return TCM_INVALID_CDB_FIELD; 878 } 879 880 size = sbc_get_size(cmd, 1); 881 cmd->t_task_lba = get_unaligned_be64(&cdb[12]); 882 883 ret = sbc_setup_write_same(cmd, cdb[10], ops); 884 if (ret) 885 return ret; 886 break; 887 default: 888 pr_err("VARIABLE_LENGTH_CMD service action" 889 " 0x%04x not supported\n", service_action); 890 return TCM_UNSUPPORTED_SCSI_OPCODE; 891 } 892 break; 893 } 894 case COMPARE_AND_WRITE: 895 if (!dev->dev_attrib.emulate_caw) { 896 pr_err_ratelimited("se_device %s/%s (vpd_unit_serial %s) reject COMPARE_AND_WRITE\n", 897 dev->se_hba->backend->ops->name, 898 config_item_name(&dev->dev_group.cg_item), 899 dev->t10_wwn.unit_serial); 900 return TCM_UNSUPPORTED_SCSI_OPCODE; 901 } 902 sectors = cdb[13]; 903 /* 904 * Currently enforce COMPARE_AND_WRITE for a single sector 905 */ 906 if (sectors > 1) { 907 pr_err("COMPARE_AND_WRITE contains NoLB: %u greater" 908 " than 1\n", sectors); 909 return TCM_INVALID_CDB_FIELD; 910 } 911 if (sbc_check_dpofua(dev, cmd, cdb)) 912 return TCM_INVALID_CDB_FIELD; 913 914 /* 915 * Double size because we have two buffers, note that 916 * zero is not an error.. 917 */ 918 size = 2 * sbc_get_size(cmd, sectors); 919 cmd->t_task_lba = get_unaligned_be64(&cdb[2]); 920 cmd->t_task_nolb = sectors; 921 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE; 922 cmd->execute_cmd = sbc_compare_and_write; 923 cmd->transport_complete_callback = compare_and_write_callback; 924 break; 925 case READ_CAPACITY: 926 size = READ_CAP_LEN; 927 cmd->execute_cmd = sbc_emulate_readcapacity; 928 break; 929 case SERVICE_ACTION_IN_16: 930 switch (cmd->t_task_cdb[1] & 0x1f) { 931 case SAI_READ_CAPACITY_16: 932 cmd->execute_cmd = sbc_emulate_readcapacity_16; 933 break; 934 case SAI_REPORT_REFERRALS: 935 cmd->execute_cmd = target_emulate_report_referrals; 936 break; 937 default: 938 pr_err("Unsupported SA: 0x%02x\n", 939 cmd->t_task_cdb[1] & 0x1f); 940 return TCM_INVALID_CDB_FIELD; 941 } 942 size = get_unaligned_be32(&cdb[10]); 943 break; 944 case SYNCHRONIZE_CACHE: 945 case SYNCHRONIZE_CACHE_16: 946 if (cdb[0] == SYNCHRONIZE_CACHE) { 947 sectors = transport_get_sectors_10(cdb); 948 cmd->t_task_lba = transport_lba_32(cdb); 949 } else { 950 sectors = transport_get_sectors_16(cdb); 951 cmd->t_task_lba = transport_lba_64(cdb); 952 } 953 if (ops->execute_sync_cache) { 954 cmd->execute_cmd = ops->execute_sync_cache; 955 goto check_lba; 956 } 957 size = 0; 958 cmd->execute_cmd = sbc_emulate_noop; 959 break; 960 case UNMAP: 961 if (!ops->execute_unmap) 962 return TCM_UNSUPPORTED_SCSI_OPCODE; 963 964 if (!dev->dev_attrib.emulate_tpu) { 965 pr_err("Got UNMAP, but backend device has" 966 " emulate_tpu disabled\n"); 967 return TCM_UNSUPPORTED_SCSI_OPCODE; 968 } 969 size = get_unaligned_be16(&cdb[7]); 970 cmd->execute_cmd = sbc_execute_unmap; 971 break; 972 case WRITE_SAME_16: 973 sectors = transport_get_sectors_16(cdb); 974 if (!sectors) { 975 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n"); 976 return TCM_INVALID_CDB_FIELD; 977 } 978 979 size = sbc_get_size(cmd, 1); 980 cmd->t_task_lba = get_unaligned_be64(&cdb[2]); 981 982 ret = sbc_setup_write_same(cmd, cdb[1], ops); 983 if (ret) 984 return ret; 985 break; 986 case WRITE_SAME: 987 sectors = transport_get_sectors_10(cdb); 988 if (!sectors) { 989 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n"); 990 return TCM_INVALID_CDB_FIELD; 991 } 992 993 size = sbc_get_size(cmd, 1); 994 cmd->t_task_lba = get_unaligned_be32(&cdb[2]); 995 996 /* 997 * Follow sbcr26 with WRITE_SAME (10) and check for the existence 998 * of byte 1 bit 3 UNMAP instead of original reserved field 999 */ 1000 ret = sbc_setup_write_same(cmd, cdb[1], ops); 1001 if (ret) 1002 return ret; 1003 break; 1004 case VERIFY: 1005 case VERIFY_16: 1006 size = 0; 1007 if (cdb[0] == VERIFY) { 1008 sectors = transport_get_sectors_10(cdb); 1009 cmd->t_task_lba = transport_lba_32(cdb); 1010 } else { 1011 sectors = transport_get_sectors_16(cdb); 1012 cmd->t_task_lba = transport_lba_64(cdb); 1013 } 1014 cmd->execute_cmd = sbc_emulate_noop; 1015 goto check_lba; 1016 case REZERO_UNIT: 1017 case SEEK_6: 1018 case SEEK_10: 1019 /* 1020 * There are still clients out there which use these old SCSI-2 1021 * commands. This mainly happens when running VMs with legacy 1022 * guest systems, connected via SCSI command pass-through to 1023 * iSCSI targets. Make them happy and return status GOOD. 1024 */ 1025 size = 0; 1026 cmd->execute_cmd = sbc_emulate_noop; 1027 break; 1028 case START_STOP: 1029 size = 0; 1030 cmd->execute_cmd = sbc_emulate_startstop; 1031 break; 1032 default: 1033 ret = spc_parse_cdb(cmd, &size); 1034 if (ret) 1035 return ret; 1036 } 1037 1038 /* reject any command that we don't have a handler for */ 1039 if (!cmd->execute_cmd) 1040 return TCM_UNSUPPORTED_SCSI_OPCODE; 1041 1042 if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) { 1043 unsigned long long end_lba; 1044 check_lba: 1045 end_lba = dev->transport->get_blocks(dev) + 1; 1046 if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) || 1047 ((cmd->t_task_lba + sectors) > end_lba)) { 1048 pr_err("cmd exceeds last lba %llu " 1049 "(lba %llu, sectors %u)\n", 1050 end_lba, cmd->t_task_lba, sectors); 1051 return TCM_ADDRESS_OUT_OF_RANGE; 1052 } 1053 1054 if (!(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) 1055 size = sbc_get_size(cmd, sectors); 1056 } 1057 1058 return target_cmd_size_check(cmd, size); 1059 } 1060 EXPORT_SYMBOL(sbc_parse_cdb); 1061 1062 u32 sbc_get_device_type(struct se_device *dev) 1063 { 1064 return TYPE_DISK; 1065 } 1066 EXPORT_SYMBOL(sbc_get_device_type); 1067 1068 static sense_reason_t 1069 sbc_execute_unmap(struct se_cmd *cmd) 1070 { 1071 struct sbc_ops *ops = cmd->protocol_data; 1072 struct se_device *dev = cmd->se_dev; 1073 unsigned char *buf, *ptr = NULL; 1074 sector_t lba; 1075 int size; 1076 u32 range; 1077 sense_reason_t ret = 0; 1078 int dl, bd_dl; 1079 1080 /* We never set ANC_SUP */ 1081 if (cmd->t_task_cdb[1]) 1082 return TCM_INVALID_CDB_FIELD; 1083 1084 if (cmd->data_length == 0) { 1085 target_complete_cmd(cmd, SAM_STAT_GOOD); 1086 return 0; 1087 } 1088 1089 if (cmd->data_length < 8) { 1090 pr_warn("UNMAP parameter list length %u too small\n", 1091 cmd->data_length); 1092 return TCM_PARAMETER_LIST_LENGTH_ERROR; 1093 } 1094 1095 buf = transport_kmap_data_sg(cmd); 1096 if (!buf) 1097 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 1098 1099 dl = get_unaligned_be16(&buf[0]); 1100 bd_dl = get_unaligned_be16(&buf[2]); 1101 1102 size = cmd->data_length - 8; 1103 if (bd_dl > size) 1104 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n", 1105 cmd->data_length, bd_dl); 1106 else 1107 size = bd_dl; 1108 1109 if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) { 1110 ret = TCM_INVALID_PARAMETER_LIST; 1111 goto err; 1112 } 1113 1114 /* First UNMAP block descriptor starts at 8 byte offset */ 1115 ptr = &buf[8]; 1116 pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u" 1117 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr); 1118 1119 while (size >= 16) { 1120 lba = get_unaligned_be64(&ptr[0]); 1121 range = get_unaligned_be32(&ptr[8]); 1122 pr_debug("UNMAP: Using lba: %llu and range: %u\n", 1123 (unsigned long long)lba, range); 1124 1125 if (range > dev->dev_attrib.max_unmap_lba_count) { 1126 ret = TCM_INVALID_PARAMETER_LIST; 1127 goto err; 1128 } 1129 1130 if (lba + range > dev->transport->get_blocks(dev) + 1) { 1131 ret = TCM_ADDRESS_OUT_OF_RANGE; 1132 goto err; 1133 } 1134 1135 if (range) { 1136 ret = ops->execute_unmap(cmd, lba, range); 1137 if (ret) 1138 goto err; 1139 } 1140 1141 ptr += 16; 1142 size -= 16; 1143 } 1144 1145 err: 1146 transport_kunmap_data_sg(cmd); 1147 if (!ret) 1148 target_complete_cmd(cmd, SAM_STAT_GOOD); 1149 return ret; 1150 } 1151 1152 void 1153 sbc_dif_generate(struct se_cmd *cmd) 1154 { 1155 struct se_device *dev = cmd->se_dev; 1156 struct t10_pi_tuple *sdt; 1157 struct scatterlist *dsg = cmd->t_data_sg, *psg; 1158 sector_t sector = cmd->t_task_lba; 1159 void *daddr, *paddr; 1160 int i, j, offset = 0; 1161 unsigned int block_size = dev->dev_attrib.block_size; 1162 1163 for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) { 1164 paddr = kmap_atomic(sg_page(psg)) + psg->offset; 1165 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; 1166 1167 for (j = 0; j < psg->length; 1168 j += sizeof(*sdt)) { 1169 __u16 crc; 1170 unsigned int avail; 1171 1172 if (offset >= dsg->length) { 1173 offset -= dsg->length; 1174 kunmap_atomic(daddr - dsg->offset); 1175 dsg = sg_next(dsg); 1176 if (!dsg) { 1177 kunmap_atomic(paddr - psg->offset); 1178 return; 1179 } 1180 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; 1181 } 1182 1183 sdt = paddr + j; 1184 avail = min(block_size, dsg->length - offset); 1185 crc = crc_t10dif(daddr + offset, avail); 1186 if (avail < block_size) { 1187 kunmap_atomic(daddr - dsg->offset); 1188 dsg = sg_next(dsg); 1189 if (!dsg) { 1190 kunmap_atomic(paddr - psg->offset); 1191 return; 1192 } 1193 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; 1194 offset = block_size - avail; 1195 crc = crc_t10dif_update(crc, daddr, offset); 1196 } else { 1197 offset += block_size; 1198 } 1199 1200 sdt->guard_tag = cpu_to_be16(crc); 1201 if (cmd->prot_type == TARGET_DIF_TYPE1_PROT) 1202 sdt->ref_tag = cpu_to_be32(sector & 0xffffffff); 1203 sdt->app_tag = 0; 1204 1205 pr_debug("DIF %s INSERT sector: %llu guard_tag: 0x%04x" 1206 " app_tag: 0x%04x ref_tag: %u\n", 1207 (cmd->data_direction == DMA_TO_DEVICE) ? 1208 "WRITE" : "READ", (unsigned long long)sector, 1209 sdt->guard_tag, sdt->app_tag, 1210 be32_to_cpu(sdt->ref_tag)); 1211 1212 sector++; 1213 } 1214 1215 kunmap_atomic(daddr - dsg->offset); 1216 kunmap_atomic(paddr - psg->offset); 1217 } 1218 } 1219 1220 static sense_reason_t 1221 sbc_dif_v1_verify(struct se_cmd *cmd, struct t10_pi_tuple *sdt, 1222 __u16 crc, sector_t sector, unsigned int ei_lba) 1223 { 1224 __be16 csum; 1225 1226 if (!(cmd->prot_checks & TARGET_DIF_CHECK_GUARD)) 1227 goto check_ref; 1228 1229 csum = cpu_to_be16(crc); 1230 1231 if (sdt->guard_tag != csum) { 1232 pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x" 1233 " csum 0x%04x\n", (unsigned long long)sector, 1234 be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum)); 1235 return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED; 1236 } 1237 1238 check_ref: 1239 if (!(cmd->prot_checks & TARGET_DIF_CHECK_REFTAG)) 1240 return 0; 1241 1242 if (cmd->prot_type == TARGET_DIF_TYPE1_PROT && 1243 be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) { 1244 pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x" 1245 " sector MSB: 0x%08x\n", (unsigned long long)sector, 1246 be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff)); 1247 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED; 1248 } 1249 1250 if (cmd->prot_type == TARGET_DIF_TYPE2_PROT && 1251 be32_to_cpu(sdt->ref_tag) != ei_lba) { 1252 pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x" 1253 " ei_lba: 0x%08x\n", (unsigned long long)sector, 1254 be32_to_cpu(sdt->ref_tag), ei_lba); 1255 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED; 1256 } 1257 1258 return 0; 1259 } 1260 1261 void sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read, 1262 struct scatterlist *sg, int sg_off) 1263 { 1264 struct se_device *dev = cmd->se_dev; 1265 struct scatterlist *psg; 1266 void *paddr, *addr; 1267 unsigned int i, len, left; 1268 unsigned int offset = sg_off; 1269 1270 if (!sg) 1271 return; 1272 1273 left = sectors * dev->prot_length; 1274 1275 for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) { 1276 unsigned int psg_len, copied = 0; 1277 1278 paddr = kmap_atomic(sg_page(psg)) + psg->offset; 1279 psg_len = min(left, psg->length); 1280 while (psg_len) { 1281 len = min(psg_len, sg->length - offset); 1282 addr = kmap_atomic(sg_page(sg)) + sg->offset + offset; 1283 1284 if (read) 1285 memcpy(paddr + copied, addr, len); 1286 else 1287 memcpy(addr, paddr + copied, len); 1288 1289 left -= len; 1290 offset += len; 1291 copied += len; 1292 psg_len -= len; 1293 1294 kunmap_atomic(addr - sg->offset - offset); 1295 1296 if (offset >= sg->length) { 1297 sg = sg_next(sg); 1298 offset = 0; 1299 } 1300 } 1301 kunmap_atomic(paddr - psg->offset); 1302 } 1303 } 1304 EXPORT_SYMBOL(sbc_dif_copy_prot); 1305 1306 sense_reason_t 1307 sbc_dif_verify(struct se_cmd *cmd, sector_t start, unsigned int sectors, 1308 unsigned int ei_lba, struct scatterlist *psg, int psg_off) 1309 { 1310 struct se_device *dev = cmd->se_dev; 1311 struct t10_pi_tuple *sdt; 1312 struct scatterlist *dsg = cmd->t_data_sg; 1313 sector_t sector = start; 1314 void *daddr, *paddr; 1315 int i; 1316 sense_reason_t rc; 1317 int dsg_off = 0; 1318 unsigned int block_size = dev->dev_attrib.block_size; 1319 1320 for (; psg && sector < start + sectors; psg = sg_next(psg)) { 1321 paddr = kmap_atomic(sg_page(psg)) + psg->offset; 1322 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; 1323 1324 for (i = psg_off; i < psg->length && 1325 sector < start + sectors; 1326 i += sizeof(*sdt)) { 1327 __u16 crc; 1328 unsigned int avail; 1329 1330 if (dsg_off >= dsg->length) { 1331 dsg_off -= dsg->length; 1332 kunmap_atomic(daddr - dsg->offset); 1333 dsg = sg_next(dsg); 1334 if (!dsg) { 1335 kunmap_atomic(paddr - psg->offset); 1336 return 0; 1337 } 1338 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; 1339 } 1340 1341 sdt = paddr + i; 1342 1343 pr_debug("DIF READ sector: %llu guard_tag: 0x%04x" 1344 " app_tag: 0x%04x ref_tag: %u\n", 1345 (unsigned long long)sector, sdt->guard_tag, 1346 sdt->app_tag, be32_to_cpu(sdt->ref_tag)); 1347 1348 if (sdt->app_tag == T10_PI_APP_ESCAPE) { 1349 dsg_off += block_size; 1350 goto next; 1351 } 1352 1353 avail = min(block_size, dsg->length - dsg_off); 1354 crc = crc_t10dif(daddr + dsg_off, avail); 1355 if (avail < block_size) { 1356 kunmap_atomic(daddr - dsg->offset); 1357 dsg = sg_next(dsg); 1358 if (!dsg) { 1359 kunmap_atomic(paddr - psg->offset); 1360 return 0; 1361 } 1362 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; 1363 dsg_off = block_size - avail; 1364 crc = crc_t10dif_update(crc, daddr, dsg_off); 1365 } else { 1366 dsg_off += block_size; 1367 } 1368 1369 rc = sbc_dif_v1_verify(cmd, sdt, crc, sector, ei_lba); 1370 if (rc) { 1371 kunmap_atomic(daddr - dsg->offset); 1372 kunmap_atomic(paddr - psg->offset); 1373 cmd->sense_info = sector; 1374 return rc; 1375 } 1376 next: 1377 sector++; 1378 ei_lba++; 1379 } 1380 1381 psg_off = 0; 1382 kunmap_atomic(daddr - dsg->offset); 1383 kunmap_atomic(paddr - psg->offset); 1384 } 1385 1386 return 0; 1387 } 1388 EXPORT_SYMBOL(sbc_dif_verify); 1389