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