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 exec_cmd_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 static sense_reason_t 274 sbc_setup_write_same(struct se_cmd *cmd, unsigned char flags, 275 struct exec_cmd_ops *ops) 276 { 277 struct se_device *dev = cmd->se_dev; 278 sector_t end_lba = dev->transport->get_blocks(dev) + 1; 279 unsigned int sectors = sbc_get_write_same_sectors(cmd); 280 sense_reason_t ret; 281 282 if ((flags & 0x04) || (flags & 0x02)) { 283 pr_err("WRITE_SAME PBDATA and LBDATA" 284 " bits not supported for Block Discard" 285 " Emulation\n"); 286 return TCM_UNSUPPORTED_SCSI_OPCODE; 287 } 288 if (sectors > cmd->se_dev->dev_attrib.max_write_same_len) { 289 pr_warn("WRITE_SAME sectors: %u exceeds max_write_same_len: %u\n", 290 sectors, cmd->se_dev->dev_attrib.max_write_same_len); 291 return TCM_INVALID_CDB_FIELD; 292 } 293 /* 294 * Sanity check for LBA wrap and request past end of device. 295 */ 296 if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) || 297 ((cmd->t_task_lba + sectors) > end_lba)) { 298 pr_err("WRITE_SAME exceeds last lba %llu (lba %llu, sectors %u)\n", 299 (unsigned long long)end_lba, cmd->t_task_lba, sectors); 300 return TCM_ADDRESS_OUT_OF_RANGE; 301 } 302 303 /* We always have ANC_SUP == 0 so setting ANCHOR is always an error */ 304 if (flags & 0x10) { 305 pr_warn("WRITE SAME with ANCHOR not supported\n"); 306 return TCM_INVALID_CDB_FIELD; 307 } 308 309 if (flags & 0x01) { 310 pr_warn("WRITE SAME with NDOB not supported\n"); 311 return TCM_INVALID_CDB_FIELD; 312 } 313 314 /* 315 * Special case for WRITE_SAME w/ UNMAP=1 that ends up getting 316 * translated into block discard requests within backend code. 317 */ 318 if (flags & 0x08) { 319 if (!ops->execute_unmap) 320 return TCM_UNSUPPORTED_SCSI_OPCODE; 321 322 if (!dev->dev_attrib.emulate_tpws) { 323 pr_err("Got WRITE_SAME w/ UNMAP=1, but backend device" 324 " has emulate_tpws disabled\n"); 325 return TCM_UNSUPPORTED_SCSI_OPCODE; 326 } 327 cmd->execute_cmd = sbc_execute_write_same_unmap; 328 return 0; 329 } 330 if (!ops->execute_write_same) 331 return TCM_UNSUPPORTED_SCSI_OPCODE; 332 333 ret = sbc_check_prot(dev, cmd, flags >> 5, sectors, true); 334 if (ret) 335 return ret; 336 337 cmd->execute_cmd = ops->execute_write_same; 338 return 0; 339 } 340 341 static sense_reason_t 342 sbc_execute_rw(struct se_cmd *cmd) 343 { 344 struct exec_cmd_ops *ops = cmd->protocol_data; 345 346 return ops->execute_rw(cmd, cmd->t_data_sg, cmd->t_data_nents, 347 cmd->data_direction); 348 } 349 350 static sense_reason_t compare_and_write_post(struct se_cmd *cmd, bool success, 351 int *post_ret) 352 { 353 struct se_device *dev = cmd->se_dev; 354 sense_reason_t ret = TCM_NO_SENSE; 355 356 spin_lock_irq(&cmd->t_state_lock); 357 if (success) { 358 *post_ret = 1; 359 360 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION) 361 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 362 } 363 spin_unlock_irq(&cmd->t_state_lock); 364 365 /* 366 * Unlock ->caw_sem originally obtained during sbc_compare_and_write() 367 * before the original READ I/O submission. 368 */ 369 up(&dev->caw_sem); 370 371 return ret; 372 } 373 374 /* 375 * compare @cmp_len bytes of @read_sgl with @cmp_sgl. On miscompare, fill 376 * @miscmp_off and return TCM_MISCOMPARE_VERIFY. 377 */ 378 static sense_reason_t 379 compare_and_write_do_cmp(struct scatterlist *read_sgl, unsigned int read_nents, 380 struct scatterlist *cmp_sgl, unsigned int cmp_nents, 381 unsigned int cmp_len, unsigned int *miscmp_off) 382 { 383 unsigned char *buf = NULL; 384 struct scatterlist *sg; 385 sense_reason_t ret; 386 unsigned int offset; 387 size_t rc; 388 int sg_cnt; 389 390 buf = kzalloc(cmp_len, GFP_KERNEL); 391 if (!buf) { 392 ret = TCM_OUT_OF_RESOURCES; 393 goto out; 394 } 395 396 rc = sg_copy_to_buffer(cmp_sgl, cmp_nents, buf, cmp_len); 397 if (!rc) { 398 pr_err("sg_copy_to_buffer() failed for compare_and_write\n"); 399 ret = TCM_OUT_OF_RESOURCES; 400 goto out; 401 } 402 /* 403 * Compare SCSI READ payload against verify payload 404 */ 405 offset = 0; 406 ret = TCM_NO_SENSE; 407 for_each_sg(read_sgl, sg, read_nents, sg_cnt) { 408 unsigned int len = min(sg->length, cmp_len); 409 unsigned char *addr = kmap_atomic(sg_page(sg)); 410 411 if (memcmp(addr, buf + offset, len)) { 412 unsigned int i; 413 414 for (i = 0; i < len && addr[i] == buf[offset + i]; i++) 415 ; 416 *miscmp_off = offset + i; 417 pr_warn("Detected MISCOMPARE at offset %u\n", 418 *miscmp_off); 419 ret = TCM_MISCOMPARE_VERIFY; 420 } 421 kunmap_atomic(addr); 422 if (ret != TCM_NO_SENSE) 423 goto out; 424 425 offset += len; 426 cmp_len -= len; 427 if (!cmp_len) 428 break; 429 } 430 pr_debug("COMPARE AND WRITE read data matches compare data\n"); 431 out: 432 kfree(buf); 433 return ret; 434 } 435 436 static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool success, 437 int *post_ret) 438 { 439 struct se_device *dev = cmd->se_dev; 440 struct sg_table write_tbl = { }; 441 struct scatterlist *write_sg; 442 struct sg_mapping_iter m; 443 unsigned int len; 444 unsigned int block_size = dev->dev_attrib.block_size; 445 unsigned int compare_len = (cmd->t_task_nolb * block_size); 446 unsigned int miscmp_off = 0; 447 sense_reason_t ret = TCM_NO_SENSE; 448 int i; 449 450 if (!success) { 451 /* 452 * Handle early failure in transport_generic_request_failure(), 453 * which will not have taken ->caw_sem yet.. 454 */ 455 if (!cmd->t_data_sg || !cmd->t_bidi_data_sg) 456 return TCM_NO_SENSE; 457 458 /* 459 * The command has been stopped or aborted so 460 * we don't have to perform the write operation. 461 */ 462 WARN_ON(!(cmd->transport_state & 463 (CMD_T_ABORTED | CMD_T_STOP))); 464 goto out; 465 } 466 /* 467 * Handle special case for zero-length COMPARE_AND_WRITE 468 */ 469 if (!cmd->data_length) 470 goto out; 471 /* 472 * Immediately exit + release dev->caw_sem if command has already 473 * been failed with a non-zero SCSI status. 474 */ 475 if (cmd->scsi_status) { 476 pr_debug("compare_and_write_callback: non zero scsi_status:" 477 " 0x%02x\n", cmd->scsi_status); 478 *post_ret = 1; 479 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION) 480 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 481 goto out; 482 } 483 484 ret = compare_and_write_do_cmp(cmd->t_bidi_data_sg, 485 cmd->t_bidi_data_nents, 486 cmd->t_data_sg, 487 cmd->t_data_nents, 488 compare_len, 489 &miscmp_off); 490 if (ret == TCM_MISCOMPARE_VERIFY) { 491 /* 492 * SBC-4 r15: 5.3 COMPARE AND WRITE command 493 * In the sense data (see 4.18 and SPC-5) the offset from the 494 * start of the Data-Out Buffer to the first byte of data that 495 * was not equal shall be reported in the INFORMATION field. 496 */ 497 cmd->sense_info = miscmp_off; 498 goto out; 499 } else if (ret) 500 goto out; 501 502 if (sg_alloc_table(&write_tbl, cmd->t_data_nents, GFP_KERNEL) < 0) { 503 pr_err("Unable to allocate compare_and_write sg\n"); 504 ret = TCM_OUT_OF_RESOURCES; 505 goto out; 506 } 507 write_sg = write_tbl.sgl; 508 509 i = 0; 510 len = compare_len; 511 sg_miter_start(&m, cmd->t_data_sg, cmd->t_data_nents, SG_MITER_TO_SG); 512 /* 513 * Currently assumes NoLB=1 and SGLs are PAGE_SIZE.. 514 */ 515 while (len) { 516 sg_miter_next(&m); 517 518 if (block_size < PAGE_SIZE) { 519 sg_set_page(&write_sg[i], m.page, block_size, 520 m.piter.sg->offset + block_size); 521 } else { 522 sg_miter_next(&m); 523 sg_set_page(&write_sg[i], m.page, block_size, 524 m.piter.sg->offset); 525 } 526 len -= block_size; 527 i++; 528 } 529 sg_miter_stop(&m); 530 /* 531 * Save the original SGL + nents values before updating to new 532 * assignments, to be released in transport_free_pages() -> 533 * transport_reset_sgl_orig() 534 */ 535 cmd->t_data_sg_orig = cmd->t_data_sg; 536 cmd->t_data_sg = write_sg; 537 cmd->t_data_nents_orig = cmd->t_data_nents; 538 cmd->t_data_nents = 1; 539 540 cmd->sam_task_attr = TCM_HEAD_TAG; 541 cmd->transport_complete_callback = compare_and_write_post; 542 /* 543 * Now reset ->execute_cmd() to the normal sbc_execute_rw() handler 544 * for submitting the adjusted SGL to write instance user-data. 545 */ 546 cmd->execute_cmd = sbc_execute_rw; 547 548 spin_lock_irq(&cmd->t_state_lock); 549 cmd->t_state = TRANSPORT_PROCESSING; 550 cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT; 551 spin_unlock_irq(&cmd->t_state_lock); 552 553 __target_execute_cmd(cmd, false); 554 555 return ret; 556 557 out: 558 /* 559 * In the MISCOMPARE or failure case, unlock ->caw_sem obtained in 560 * sbc_compare_and_write() before the original READ I/O submission. 561 */ 562 up(&dev->caw_sem); 563 sg_free_table(&write_tbl); 564 return ret; 565 } 566 567 static sense_reason_t 568 sbc_compare_and_write(struct se_cmd *cmd) 569 { 570 struct exec_cmd_ops *ops = cmd->protocol_data; 571 struct se_device *dev = cmd->se_dev; 572 sense_reason_t ret; 573 int rc; 574 /* 575 * Submit the READ first for COMPARE_AND_WRITE to perform the 576 * comparision using SGLs at cmd->t_bidi_data_sg.. 577 */ 578 rc = down_interruptible(&dev->caw_sem); 579 if (rc != 0) { 580 cmd->transport_complete_callback = NULL; 581 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 582 } 583 /* 584 * Reset cmd->data_length to individual block_size in order to not 585 * confuse backend drivers that depend on this value matching the 586 * size of the I/O being submitted. 587 */ 588 cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size; 589 590 ret = ops->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents, 591 DMA_FROM_DEVICE); 592 if (ret) { 593 cmd->transport_complete_callback = NULL; 594 up(&dev->caw_sem); 595 return ret; 596 } 597 /* 598 * Unlock of dev->caw_sem to occur in compare_and_write_callback() 599 * upon MISCOMPARE, or in compare_and_write_done() upon completion 600 * of WRITE instance user-data. 601 */ 602 return TCM_NO_SENSE; 603 } 604 605 static int 606 sbc_set_prot_op_checks(u8 protect, bool fabric_prot, enum target_prot_type prot_type, 607 bool is_write, struct se_cmd *cmd) 608 { 609 if (is_write) { 610 cmd->prot_op = fabric_prot ? TARGET_PROT_DOUT_STRIP : 611 protect ? TARGET_PROT_DOUT_PASS : 612 TARGET_PROT_DOUT_INSERT; 613 switch (protect) { 614 case 0x0: 615 case 0x3: 616 cmd->prot_checks = 0; 617 break; 618 case 0x1: 619 case 0x5: 620 cmd->prot_checks = TARGET_DIF_CHECK_GUARD; 621 if (prot_type == TARGET_DIF_TYPE1_PROT) 622 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG; 623 break; 624 case 0x2: 625 if (prot_type == TARGET_DIF_TYPE1_PROT) 626 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG; 627 break; 628 case 0x4: 629 cmd->prot_checks = TARGET_DIF_CHECK_GUARD; 630 break; 631 default: 632 pr_err("Unsupported protect field %d\n", protect); 633 return -EINVAL; 634 } 635 } else { 636 cmd->prot_op = fabric_prot ? TARGET_PROT_DIN_INSERT : 637 protect ? TARGET_PROT_DIN_PASS : 638 TARGET_PROT_DIN_STRIP; 639 switch (protect) { 640 case 0x0: 641 case 0x1: 642 case 0x5: 643 cmd->prot_checks = TARGET_DIF_CHECK_GUARD; 644 if (prot_type == TARGET_DIF_TYPE1_PROT) 645 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG; 646 break; 647 case 0x2: 648 if (prot_type == TARGET_DIF_TYPE1_PROT) 649 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG; 650 break; 651 case 0x3: 652 cmd->prot_checks = 0; 653 break; 654 case 0x4: 655 cmd->prot_checks = TARGET_DIF_CHECK_GUARD; 656 break; 657 default: 658 pr_err("Unsupported protect field %d\n", protect); 659 return -EINVAL; 660 } 661 } 662 663 return 0; 664 } 665 666 static sense_reason_t 667 sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char protect, 668 u32 sectors, bool is_write) 669 { 670 int sp_ops = cmd->se_sess->sup_prot_ops; 671 int pi_prot_type = dev->dev_attrib.pi_prot_type; 672 bool fabric_prot = false; 673 674 if (!cmd->t_prot_sg || !cmd->t_prot_nents) { 675 if (unlikely(protect && 676 !dev->dev_attrib.pi_prot_type && !cmd->se_sess->sess_prot_type)) { 677 pr_err("CDB contains protect bit, but device + fabric does" 678 " not advertise PROTECT=1 feature bit\n"); 679 return TCM_INVALID_CDB_FIELD; 680 } 681 if (cmd->prot_pto) 682 return TCM_NO_SENSE; 683 } 684 685 switch (dev->dev_attrib.pi_prot_type) { 686 case TARGET_DIF_TYPE3_PROT: 687 cmd->reftag_seed = 0xffffffff; 688 break; 689 case TARGET_DIF_TYPE2_PROT: 690 if (protect) 691 return TCM_INVALID_CDB_FIELD; 692 693 cmd->reftag_seed = cmd->t_task_lba; 694 break; 695 case TARGET_DIF_TYPE1_PROT: 696 cmd->reftag_seed = cmd->t_task_lba; 697 break; 698 case TARGET_DIF_TYPE0_PROT: 699 /* 700 * See if the fabric supports T10-PI, and the session has been 701 * configured to allow export PROTECT=1 feature bit with backend 702 * devices that don't support T10-PI. 703 */ 704 fabric_prot = is_write ? 705 !!(sp_ops & (TARGET_PROT_DOUT_PASS | TARGET_PROT_DOUT_STRIP)) : 706 !!(sp_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DIN_INSERT)); 707 708 if (fabric_prot && cmd->se_sess->sess_prot_type) { 709 pi_prot_type = cmd->se_sess->sess_prot_type; 710 break; 711 } 712 if (!protect) 713 return TCM_NO_SENSE; 714 fallthrough; 715 default: 716 pr_err("Unable to determine pi_prot_type for CDB: 0x%02x " 717 "PROTECT: 0x%02x\n", cmd->t_task_cdb[0], protect); 718 return TCM_INVALID_CDB_FIELD; 719 } 720 721 if (sbc_set_prot_op_checks(protect, fabric_prot, pi_prot_type, is_write, cmd)) 722 return TCM_INVALID_CDB_FIELD; 723 724 cmd->prot_type = pi_prot_type; 725 cmd->prot_length = dev->prot_length * sectors; 726 727 /** 728 * In case protection information exists over the wire 729 * we modify command data length to describe pure data. 730 * The actual transfer length is data length + protection 731 * length 732 **/ 733 if (protect) 734 cmd->data_length = sectors * dev->dev_attrib.block_size; 735 736 pr_debug("%s: prot_type=%d, data_length=%d, prot_length=%d " 737 "prot_op=%d prot_checks=%d\n", 738 __func__, cmd->prot_type, cmd->data_length, cmd->prot_length, 739 cmd->prot_op, cmd->prot_checks); 740 741 return TCM_NO_SENSE; 742 } 743 744 static int 745 sbc_check_dpofua(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb) 746 { 747 if (cdb[1] & 0x10) { 748 /* see explanation in spc_emulate_modesense */ 749 if (!target_check_fua(dev)) { 750 pr_err("Got CDB: 0x%02x with DPO bit set, but device" 751 " does not advertise support for DPO\n", cdb[0]); 752 return -EINVAL; 753 } 754 } 755 if (cdb[1] & 0x8) { 756 if (!target_check_fua(dev)) { 757 pr_err("Got CDB: 0x%02x with FUA bit set, but device" 758 " does not advertise support for FUA write\n", 759 cdb[0]); 760 return -EINVAL; 761 } 762 cmd->se_cmd_flags |= SCF_FUA; 763 } 764 return 0; 765 } 766 767 sense_reason_t 768 sbc_parse_cdb(struct se_cmd *cmd, struct exec_cmd_ops *ops) 769 { 770 struct se_device *dev = cmd->se_dev; 771 unsigned char *cdb = cmd->t_task_cdb; 772 unsigned int size; 773 u32 sectors = 0; 774 sense_reason_t ret; 775 776 cmd->protocol_data = ops; 777 778 switch (cdb[0]) { 779 case READ_6: 780 sectors = transport_get_sectors_6(cdb); 781 cmd->t_task_lba = transport_lba_21(cdb); 782 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 783 cmd->execute_cmd = sbc_execute_rw; 784 break; 785 case READ_10: 786 sectors = transport_get_sectors_10(cdb); 787 cmd->t_task_lba = transport_lba_32(cdb); 788 789 if (sbc_check_dpofua(dev, cmd, cdb)) 790 return TCM_INVALID_CDB_FIELD; 791 792 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false); 793 if (ret) 794 return ret; 795 796 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 797 cmd->execute_cmd = sbc_execute_rw; 798 break; 799 case READ_12: 800 sectors = transport_get_sectors_12(cdb); 801 cmd->t_task_lba = transport_lba_32(cdb); 802 803 if (sbc_check_dpofua(dev, cmd, cdb)) 804 return TCM_INVALID_CDB_FIELD; 805 806 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false); 807 if (ret) 808 return ret; 809 810 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 811 cmd->execute_cmd = sbc_execute_rw; 812 break; 813 case READ_16: 814 sectors = transport_get_sectors_16(cdb); 815 cmd->t_task_lba = transport_lba_64(cdb); 816 817 if (sbc_check_dpofua(dev, cmd, cdb)) 818 return TCM_INVALID_CDB_FIELD; 819 820 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false); 821 if (ret) 822 return ret; 823 824 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 825 cmd->execute_cmd = sbc_execute_rw; 826 break; 827 case WRITE_6: 828 sectors = transport_get_sectors_6(cdb); 829 cmd->t_task_lba = transport_lba_21(cdb); 830 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 831 cmd->execute_cmd = sbc_execute_rw; 832 break; 833 case WRITE_10: 834 case WRITE_VERIFY: 835 sectors = transport_get_sectors_10(cdb); 836 cmd->t_task_lba = transport_lba_32(cdb); 837 838 if (sbc_check_dpofua(dev, cmd, cdb)) 839 return TCM_INVALID_CDB_FIELD; 840 841 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, true); 842 if (ret) 843 return ret; 844 845 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 846 cmd->execute_cmd = sbc_execute_rw; 847 break; 848 case WRITE_12: 849 sectors = transport_get_sectors_12(cdb); 850 cmd->t_task_lba = transport_lba_32(cdb); 851 852 if (sbc_check_dpofua(dev, cmd, cdb)) 853 return TCM_INVALID_CDB_FIELD; 854 855 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, true); 856 if (ret) 857 return ret; 858 859 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 860 cmd->execute_cmd = sbc_execute_rw; 861 break; 862 case WRITE_16: 863 case WRITE_VERIFY_16: 864 sectors = transport_get_sectors_16(cdb); 865 cmd->t_task_lba = transport_lba_64(cdb); 866 867 if (sbc_check_dpofua(dev, cmd, cdb)) 868 return TCM_INVALID_CDB_FIELD; 869 870 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, true); 871 if (ret) 872 return ret; 873 874 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 875 cmd->execute_cmd = sbc_execute_rw; 876 break; 877 case VARIABLE_LENGTH_CMD: 878 { 879 u16 service_action = get_unaligned_be16(&cdb[8]); 880 switch (service_action) { 881 case WRITE_SAME_32: 882 sectors = transport_get_sectors_32(cdb); 883 if (!sectors) { 884 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not" 885 " supported\n"); 886 return TCM_INVALID_CDB_FIELD; 887 } 888 889 size = sbc_get_size(cmd, 1); 890 cmd->t_task_lba = get_unaligned_be64(&cdb[12]); 891 892 ret = sbc_setup_write_same(cmd, cdb[10], ops); 893 if (ret) 894 return ret; 895 break; 896 default: 897 pr_err("VARIABLE_LENGTH_CMD service action" 898 " 0x%04x not supported\n", service_action); 899 return TCM_UNSUPPORTED_SCSI_OPCODE; 900 } 901 break; 902 } 903 case COMPARE_AND_WRITE: 904 if (!dev->dev_attrib.emulate_caw) { 905 pr_err_ratelimited("se_device %s/%s (vpd_unit_serial %s) reject COMPARE_AND_WRITE\n", 906 dev->se_hba->backend->ops->name, 907 config_item_name(&dev->dev_group.cg_item), 908 dev->t10_wwn.unit_serial); 909 return TCM_UNSUPPORTED_SCSI_OPCODE; 910 } 911 sectors = cdb[13]; 912 /* 913 * Currently enforce COMPARE_AND_WRITE for a single sector 914 */ 915 if (sectors > 1) { 916 pr_err("COMPARE_AND_WRITE contains NoLB: %u greater" 917 " than 1\n", sectors); 918 return TCM_INVALID_CDB_FIELD; 919 } 920 if (sbc_check_dpofua(dev, cmd, cdb)) 921 return TCM_INVALID_CDB_FIELD; 922 923 /* 924 * Double size because we have two buffers, note that 925 * zero is not an error.. 926 */ 927 size = 2 * sbc_get_size(cmd, sectors); 928 cmd->t_task_lba = get_unaligned_be64(&cdb[2]); 929 cmd->t_task_nolb = sectors; 930 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE; 931 cmd->execute_cmd = sbc_compare_and_write; 932 cmd->transport_complete_callback = compare_and_write_callback; 933 break; 934 case READ_CAPACITY: 935 size = READ_CAP_LEN; 936 cmd->execute_cmd = sbc_emulate_readcapacity; 937 break; 938 case SERVICE_ACTION_IN_16: 939 switch (cmd->t_task_cdb[1] & 0x1f) { 940 case SAI_READ_CAPACITY_16: 941 cmd->execute_cmd = sbc_emulate_readcapacity_16; 942 break; 943 case SAI_REPORT_REFERRALS: 944 cmd->execute_cmd = target_emulate_report_referrals; 945 break; 946 default: 947 pr_err("Unsupported SA: 0x%02x\n", 948 cmd->t_task_cdb[1] & 0x1f); 949 return TCM_INVALID_CDB_FIELD; 950 } 951 size = get_unaligned_be32(&cdb[10]); 952 break; 953 case SYNCHRONIZE_CACHE: 954 case SYNCHRONIZE_CACHE_16: 955 if (cdb[0] == SYNCHRONIZE_CACHE) { 956 sectors = transport_get_sectors_10(cdb); 957 cmd->t_task_lba = transport_lba_32(cdb); 958 } else { 959 sectors = transport_get_sectors_16(cdb); 960 cmd->t_task_lba = transport_lba_64(cdb); 961 } 962 if (ops->execute_sync_cache) { 963 cmd->execute_cmd = ops->execute_sync_cache; 964 goto check_lba; 965 } 966 size = 0; 967 cmd->execute_cmd = sbc_emulate_noop; 968 break; 969 case UNMAP: 970 if (!ops->execute_unmap) 971 return TCM_UNSUPPORTED_SCSI_OPCODE; 972 973 if (!dev->dev_attrib.emulate_tpu) { 974 pr_err("Got UNMAP, but backend device has" 975 " emulate_tpu disabled\n"); 976 return TCM_UNSUPPORTED_SCSI_OPCODE; 977 } 978 size = get_unaligned_be16(&cdb[7]); 979 cmd->execute_cmd = sbc_execute_unmap; 980 break; 981 case WRITE_SAME_16: 982 sectors = transport_get_sectors_16(cdb); 983 if (!sectors) { 984 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n"); 985 return TCM_INVALID_CDB_FIELD; 986 } 987 988 size = sbc_get_size(cmd, 1); 989 cmd->t_task_lba = get_unaligned_be64(&cdb[2]); 990 991 ret = sbc_setup_write_same(cmd, cdb[1], ops); 992 if (ret) 993 return ret; 994 break; 995 case WRITE_SAME: 996 sectors = transport_get_sectors_10(cdb); 997 if (!sectors) { 998 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n"); 999 return TCM_INVALID_CDB_FIELD; 1000 } 1001 1002 size = sbc_get_size(cmd, 1); 1003 cmd->t_task_lba = get_unaligned_be32(&cdb[2]); 1004 1005 /* 1006 * Follow sbcr26 with WRITE_SAME (10) and check for the existence 1007 * of byte 1 bit 3 UNMAP instead of original reserved field 1008 */ 1009 ret = sbc_setup_write_same(cmd, cdb[1], ops); 1010 if (ret) 1011 return ret; 1012 break; 1013 case VERIFY: 1014 case VERIFY_16: 1015 size = 0; 1016 if (cdb[0] == VERIFY) { 1017 sectors = transport_get_sectors_10(cdb); 1018 cmd->t_task_lba = transport_lba_32(cdb); 1019 } else { 1020 sectors = transport_get_sectors_16(cdb); 1021 cmd->t_task_lba = transport_lba_64(cdb); 1022 } 1023 cmd->execute_cmd = sbc_emulate_noop; 1024 goto check_lba; 1025 case REZERO_UNIT: 1026 case SEEK_6: 1027 case SEEK_10: 1028 /* 1029 * There are still clients out there which use these old SCSI-2 1030 * commands. This mainly happens when running VMs with legacy 1031 * guest systems, connected via SCSI command pass-through to 1032 * iSCSI targets. Make them happy and return status GOOD. 1033 */ 1034 size = 0; 1035 cmd->execute_cmd = sbc_emulate_noop; 1036 break; 1037 case START_STOP: 1038 size = 0; 1039 cmd->execute_cmd = sbc_emulate_startstop; 1040 break; 1041 default: 1042 ret = spc_parse_cdb(cmd, &size); 1043 if (ret) 1044 return ret; 1045 } 1046 1047 /* reject any command that we don't have a handler for */ 1048 if (!cmd->execute_cmd) 1049 return TCM_UNSUPPORTED_SCSI_OPCODE; 1050 1051 if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) { 1052 unsigned long long end_lba; 1053 check_lba: 1054 end_lba = dev->transport->get_blocks(dev) + 1; 1055 if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) || 1056 ((cmd->t_task_lba + sectors) > end_lba)) { 1057 pr_err("cmd exceeds last lba %llu " 1058 "(lba %llu, sectors %u)\n", 1059 end_lba, cmd->t_task_lba, sectors); 1060 return TCM_ADDRESS_OUT_OF_RANGE; 1061 } 1062 1063 if (!(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) 1064 size = sbc_get_size(cmd, sectors); 1065 } 1066 1067 return target_cmd_size_check(cmd, size); 1068 } 1069 EXPORT_SYMBOL(sbc_parse_cdb); 1070 1071 u32 sbc_get_device_type(struct se_device *dev) 1072 { 1073 return TYPE_DISK; 1074 } 1075 EXPORT_SYMBOL(sbc_get_device_type); 1076 1077 static sense_reason_t 1078 sbc_execute_unmap(struct se_cmd *cmd) 1079 { 1080 struct exec_cmd_ops *ops = cmd->protocol_data; 1081 struct se_device *dev = cmd->se_dev; 1082 unsigned char *buf, *ptr = NULL; 1083 sector_t lba; 1084 int size; 1085 u32 range; 1086 sense_reason_t ret = 0; 1087 int dl, bd_dl; 1088 1089 /* We never set ANC_SUP */ 1090 if (cmd->t_task_cdb[1]) 1091 return TCM_INVALID_CDB_FIELD; 1092 1093 if (cmd->data_length == 0) { 1094 target_complete_cmd(cmd, SAM_STAT_GOOD); 1095 return 0; 1096 } 1097 1098 if (cmd->data_length < 8) { 1099 pr_warn("UNMAP parameter list length %u too small\n", 1100 cmd->data_length); 1101 return TCM_PARAMETER_LIST_LENGTH_ERROR; 1102 } 1103 1104 buf = transport_kmap_data_sg(cmd); 1105 if (!buf) 1106 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 1107 1108 dl = get_unaligned_be16(&buf[0]); 1109 bd_dl = get_unaligned_be16(&buf[2]); 1110 1111 size = cmd->data_length - 8; 1112 if (bd_dl > size) 1113 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n", 1114 cmd->data_length, bd_dl); 1115 else 1116 size = bd_dl; 1117 1118 if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) { 1119 ret = TCM_INVALID_PARAMETER_LIST; 1120 goto err; 1121 } 1122 1123 /* First UNMAP block descriptor starts at 8 byte offset */ 1124 ptr = &buf[8]; 1125 pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u" 1126 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr); 1127 1128 while (size >= 16) { 1129 lba = get_unaligned_be64(&ptr[0]); 1130 range = get_unaligned_be32(&ptr[8]); 1131 pr_debug("UNMAP: Using lba: %llu and range: %u\n", 1132 (unsigned long long)lba, range); 1133 1134 if (range > dev->dev_attrib.max_unmap_lba_count) { 1135 ret = TCM_INVALID_PARAMETER_LIST; 1136 goto err; 1137 } 1138 1139 if (lba + range > dev->transport->get_blocks(dev) + 1) { 1140 ret = TCM_ADDRESS_OUT_OF_RANGE; 1141 goto err; 1142 } 1143 1144 if (range) { 1145 ret = ops->execute_unmap(cmd, lba, range); 1146 if (ret) 1147 goto err; 1148 } 1149 1150 ptr += 16; 1151 size -= 16; 1152 } 1153 1154 err: 1155 transport_kunmap_data_sg(cmd); 1156 if (!ret) 1157 target_complete_cmd(cmd, SAM_STAT_GOOD); 1158 return ret; 1159 } 1160 1161 void 1162 sbc_dif_generate(struct se_cmd *cmd) 1163 { 1164 struct se_device *dev = cmd->se_dev; 1165 struct t10_pi_tuple *sdt; 1166 struct scatterlist *dsg = cmd->t_data_sg, *psg; 1167 sector_t sector = cmd->t_task_lba; 1168 void *daddr, *paddr; 1169 int i, j, offset = 0; 1170 unsigned int block_size = dev->dev_attrib.block_size; 1171 1172 for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) { 1173 paddr = kmap_atomic(sg_page(psg)) + psg->offset; 1174 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; 1175 1176 for (j = 0; j < psg->length; 1177 j += sizeof(*sdt)) { 1178 __u16 crc; 1179 unsigned int avail; 1180 1181 if (offset >= dsg->length) { 1182 offset -= dsg->length; 1183 kunmap_atomic(daddr - dsg->offset); 1184 dsg = sg_next(dsg); 1185 if (!dsg) { 1186 kunmap_atomic(paddr - psg->offset); 1187 return; 1188 } 1189 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; 1190 } 1191 1192 sdt = paddr + j; 1193 avail = min(block_size, dsg->length - offset); 1194 crc = crc_t10dif(daddr + offset, avail); 1195 if (avail < block_size) { 1196 kunmap_atomic(daddr - dsg->offset); 1197 dsg = sg_next(dsg); 1198 if (!dsg) { 1199 kunmap_atomic(paddr - psg->offset); 1200 return; 1201 } 1202 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; 1203 offset = block_size - avail; 1204 crc = crc_t10dif_update(crc, daddr, offset); 1205 } else { 1206 offset += block_size; 1207 } 1208 1209 sdt->guard_tag = cpu_to_be16(crc); 1210 if (cmd->prot_type == TARGET_DIF_TYPE1_PROT) 1211 sdt->ref_tag = cpu_to_be32(sector & 0xffffffff); 1212 sdt->app_tag = 0; 1213 1214 pr_debug("DIF %s INSERT sector: %llu guard_tag: 0x%04x" 1215 " app_tag: 0x%04x ref_tag: %u\n", 1216 (cmd->data_direction == DMA_TO_DEVICE) ? 1217 "WRITE" : "READ", (unsigned long long)sector, 1218 sdt->guard_tag, sdt->app_tag, 1219 be32_to_cpu(sdt->ref_tag)); 1220 1221 sector++; 1222 } 1223 1224 kunmap_atomic(daddr - dsg->offset); 1225 kunmap_atomic(paddr - psg->offset); 1226 } 1227 } 1228 1229 static sense_reason_t 1230 sbc_dif_v1_verify(struct se_cmd *cmd, struct t10_pi_tuple *sdt, 1231 __u16 crc, sector_t sector, unsigned int ei_lba) 1232 { 1233 __be16 csum; 1234 1235 if (!(cmd->prot_checks & TARGET_DIF_CHECK_GUARD)) 1236 goto check_ref; 1237 1238 csum = cpu_to_be16(crc); 1239 1240 if (sdt->guard_tag != csum) { 1241 pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x" 1242 " csum 0x%04x\n", (unsigned long long)sector, 1243 be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum)); 1244 return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED; 1245 } 1246 1247 check_ref: 1248 if (!(cmd->prot_checks & TARGET_DIF_CHECK_REFTAG)) 1249 return 0; 1250 1251 if (cmd->prot_type == TARGET_DIF_TYPE1_PROT && 1252 be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) { 1253 pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x" 1254 " sector MSB: 0x%08x\n", (unsigned long long)sector, 1255 be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff)); 1256 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED; 1257 } 1258 1259 if (cmd->prot_type == TARGET_DIF_TYPE2_PROT && 1260 be32_to_cpu(sdt->ref_tag) != ei_lba) { 1261 pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x" 1262 " ei_lba: 0x%08x\n", (unsigned long long)sector, 1263 be32_to_cpu(sdt->ref_tag), ei_lba); 1264 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED; 1265 } 1266 1267 return 0; 1268 } 1269 1270 void sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read, 1271 struct scatterlist *sg, int sg_off) 1272 { 1273 struct se_device *dev = cmd->se_dev; 1274 struct scatterlist *psg; 1275 void *paddr, *addr; 1276 unsigned int i, len, left; 1277 unsigned int offset = sg_off; 1278 1279 if (!sg) 1280 return; 1281 1282 left = sectors * dev->prot_length; 1283 1284 for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) { 1285 unsigned int psg_len, copied = 0; 1286 1287 paddr = kmap_atomic(sg_page(psg)) + psg->offset; 1288 psg_len = min(left, psg->length); 1289 while (psg_len) { 1290 len = min(psg_len, sg->length - offset); 1291 addr = kmap_atomic(sg_page(sg)) + sg->offset + offset; 1292 1293 if (read) 1294 memcpy(paddr + copied, addr, len); 1295 else 1296 memcpy(addr, paddr + copied, len); 1297 1298 left -= len; 1299 offset += len; 1300 copied += len; 1301 psg_len -= len; 1302 1303 kunmap_atomic(addr - sg->offset - offset); 1304 1305 if (offset >= sg->length) { 1306 sg = sg_next(sg); 1307 offset = 0; 1308 } 1309 } 1310 kunmap_atomic(paddr - psg->offset); 1311 } 1312 } 1313 EXPORT_SYMBOL(sbc_dif_copy_prot); 1314 1315 sense_reason_t 1316 sbc_dif_verify(struct se_cmd *cmd, sector_t start, unsigned int sectors, 1317 unsigned int ei_lba, struct scatterlist *psg, int psg_off) 1318 { 1319 struct se_device *dev = cmd->se_dev; 1320 struct t10_pi_tuple *sdt; 1321 struct scatterlist *dsg = cmd->t_data_sg; 1322 sector_t sector = start; 1323 void *daddr, *paddr; 1324 int i; 1325 sense_reason_t rc; 1326 int dsg_off = 0; 1327 unsigned int block_size = dev->dev_attrib.block_size; 1328 1329 for (; psg && sector < start + sectors; psg = sg_next(psg)) { 1330 paddr = kmap_atomic(sg_page(psg)) + psg->offset; 1331 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; 1332 1333 for (i = psg_off; i < psg->length && 1334 sector < start + sectors; 1335 i += sizeof(*sdt)) { 1336 __u16 crc; 1337 unsigned int avail; 1338 1339 if (dsg_off >= dsg->length) { 1340 dsg_off -= dsg->length; 1341 kunmap_atomic(daddr - dsg->offset); 1342 dsg = sg_next(dsg); 1343 if (!dsg) { 1344 kunmap_atomic(paddr - psg->offset); 1345 return 0; 1346 } 1347 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; 1348 } 1349 1350 sdt = paddr + i; 1351 1352 pr_debug("DIF READ sector: %llu guard_tag: 0x%04x" 1353 " app_tag: 0x%04x ref_tag: %u\n", 1354 (unsigned long long)sector, sdt->guard_tag, 1355 sdt->app_tag, be32_to_cpu(sdt->ref_tag)); 1356 1357 if (sdt->app_tag == T10_PI_APP_ESCAPE) { 1358 dsg_off += block_size; 1359 goto next; 1360 } 1361 1362 avail = min(block_size, dsg->length - dsg_off); 1363 crc = crc_t10dif(daddr + dsg_off, avail); 1364 if (avail < block_size) { 1365 kunmap_atomic(daddr - dsg->offset); 1366 dsg = sg_next(dsg); 1367 if (!dsg) { 1368 kunmap_atomic(paddr - psg->offset); 1369 return 0; 1370 } 1371 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; 1372 dsg_off = block_size - avail; 1373 crc = crc_t10dif_update(crc, daddr, dsg_off); 1374 } else { 1375 dsg_off += block_size; 1376 } 1377 1378 rc = sbc_dif_v1_verify(cmd, sdt, crc, sector, ei_lba); 1379 if (rc) { 1380 kunmap_atomic(daddr - dsg->offset); 1381 kunmap_atomic(paddr - psg->offset); 1382 cmd->sense_info = sector; 1383 return rc; 1384 } 1385 next: 1386 sector++; 1387 ei_lba++; 1388 } 1389 1390 psg_off = 0; 1391 kunmap_atomic(daddr - dsg->offset); 1392 kunmap_atomic(paddr - psg->offset); 1393 } 1394 1395 return 0; 1396 } 1397 EXPORT_SYMBOL(sbc_dif_verify); 1398