1 /* 2 * SCSI Block Commands (SBC) parsing and emulation. 3 * 4 * (c) Copyright 2002-2013 Datera, Inc. 5 * 6 * Nicholas A. Bellinger <nab@kernel.org> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 21 */ 22 23 #include <linux/kernel.h> 24 #include <linux/module.h> 25 #include <linux/ratelimit.h> 26 #include <asm/unaligned.h> 27 #include <scsi/scsi.h> 28 #include <scsi/scsi_tcq.h> 29 30 #include <target/target_core_base.h> 31 #include <target/target_core_backend.h> 32 #include <target/target_core_fabric.h> 33 34 #include "target_core_internal.h" 35 #include "target_core_ua.h" 36 37 38 static sense_reason_t 39 sbc_emulate_readcapacity(struct se_cmd *cmd) 40 { 41 struct se_device *dev = cmd->se_dev; 42 unsigned char *cdb = cmd->t_task_cdb; 43 unsigned long long blocks_long = dev->transport->get_blocks(dev); 44 unsigned char *rbuf; 45 unsigned char buf[8]; 46 u32 blocks; 47 48 /* 49 * SBC-2 says: 50 * If the PMI bit is set to zero and the LOGICAL BLOCK 51 * ADDRESS field is not set to zero, the device server shall 52 * terminate the command with CHECK CONDITION status with 53 * the sense key set to ILLEGAL REQUEST and the additional 54 * sense code set to INVALID FIELD IN CDB. 55 * 56 * In SBC-3, these fields are obsolete, but some SCSI 57 * compliance tests actually check this, so we might as well 58 * follow SBC-2. 59 */ 60 if (!(cdb[8] & 1) && !!(cdb[2] | cdb[3] | cdb[4] | cdb[5])) 61 return TCM_INVALID_CDB_FIELD; 62 63 if (blocks_long >= 0x00000000ffffffff) 64 blocks = 0xffffffff; 65 else 66 blocks = (u32)blocks_long; 67 68 buf[0] = (blocks >> 24) & 0xff; 69 buf[1] = (blocks >> 16) & 0xff; 70 buf[2] = (blocks >> 8) & 0xff; 71 buf[3] = blocks & 0xff; 72 buf[4] = (dev->dev_attrib.block_size >> 24) & 0xff; 73 buf[5] = (dev->dev_attrib.block_size >> 16) & 0xff; 74 buf[6] = (dev->dev_attrib.block_size >> 8) & 0xff; 75 buf[7] = dev->dev_attrib.block_size & 0xff; 76 77 rbuf = transport_kmap_data_sg(cmd); 78 if (rbuf) { 79 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length)); 80 transport_kunmap_data_sg(cmd); 81 } 82 83 target_complete_cmd(cmd, GOOD); 84 return 0; 85 } 86 87 static sense_reason_t 88 sbc_emulate_readcapacity_16(struct se_cmd *cmd) 89 { 90 struct se_device *dev = cmd->se_dev; 91 unsigned char *rbuf; 92 unsigned char buf[32]; 93 unsigned long long blocks = dev->transport->get_blocks(dev); 94 95 memset(buf, 0, sizeof(buf)); 96 buf[0] = (blocks >> 56) & 0xff; 97 buf[1] = (blocks >> 48) & 0xff; 98 buf[2] = (blocks >> 40) & 0xff; 99 buf[3] = (blocks >> 32) & 0xff; 100 buf[4] = (blocks >> 24) & 0xff; 101 buf[5] = (blocks >> 16) & 0xff; 102 buf[6] = (blocks >> 8) & 0xff; 103 buf[7] = blocks & 0xff; 104 buf[8] = (dev->dev_attrib.block_size >> 24) & 0xff; 105 buf[9] = (dev->dev_attrib.block_size >> 16) & 0xff; 106 buf[10] = (dev->dev_attrib.block_size >> 8) & 0xff; 107 buf[11] = dev->dev_attrib.block_size & 0xff; 108 /* 109 * Set Thin Provisioning Enable bit following sbc3r22 in section 110 * READ CAPACITY (16) byte 14 if emulate_tpu or emulate_tpws is enabled. 111 */ 112 if (dev->dev_attrib.emulate_tpu || dev->dev_attrib.emulate_tpws) 113 buf[14] = 0x80; 114 115 rbuf = transport_kmap_data_sg(cmd); 116 if (rbuf) { 117 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length)); 118 transport_kunmap_data_sg(cmd); 119 } 120 121 target_complete_cmd(cmd, GOOD); 122 return 0; 123 } 124 125 sector_t sbc_get_write_same_sectors(struct se_cmd *cmd) 126 { 127 u32 num_blocks; 128 129 if (cmd->t_task_cdb[0] == WRITE_SAME) 130 num_blocks = get_unaligned_be16(&cmd->t_task_cdb[7]); 131 else if (cmd->t_task_cdb[0] == WRITE_SAME_16) 132 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[10]); 133 else /* WRITE_SAME_32 via VARIABLE_LENGTH_CMD */ 134 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[28]); 135 136 /* 137 * Use the explicit range when non zero is supplied, otherwise calculate 138 * the remaining range based on ->get_blocks() - starting LBA. 139 */ 140 if (num_blocks) 141 return num_blocks; 142 143 return cmd->se_dev->transport->get_blocks(cmd->se_dev) - 144 cmd->t_task_lba + 1; 145 } 146 EXPORT_SYMBOL(sbc_get_write_same_sectors); 147 148 static sense_reason_t 149 sbc_emulate_noop(struct se_cmd *cmd) 150 { 151 target_complete_cmd(cmd, GOOD); 152 return 0; 153 } 154 155 static inline u32 sbc_get_size(struct se_cmd *cmd, u32 sectors) 156 { 157 return cmd->se_dev->dev_attrib.block_size * sectors; 158 } 159 160 static int sbc_check_valid_sectors(struct se_cmd *cmd) 161 { 162 struct se_device *dev = cmd->se_dev; 163 unsigned long long end_lba; 164 u32 sectors; 165 166 sectors = cmd->data_length / dev->dev_attrib.block_size; 167 end_lba = dev->transport->get_blocks(dev) + 1; 168 169 if (cmd->t_task_lba + sectors > end_lba) { 170 pr_err("target: lba %llu, sectors %u exceeds end lba %llu\n", 171 cmd->t_task_lba, sectors, end_lba); 172 return -EINVAL; 173 } 174 175 return 0; 176 } 177 178 static inline u32 transport_get_sectors_6(unsigned char *cdb) 179 { 180 /* 181 * Use 8-bit sector value. SBC-3 says: 182 * 183 * A TRANSFER LENGTH field set to zero specifies that 256 184 * logical blocks shall be written. Any other value 185 * specifies the number of logical blocks that shall be 186 * written. 187 */ 188 return cdb[4] ? : 256; 189 } 190 191 static inline u32 transport_get_sectors_10(unsigned char *cdb) 192 { 193 return (u32)(cdb[7] << 8) + cdb[8]; 194 } 195 196 static inline u32 transport_get_sectors_12(unsigned char *cdb) 197 { 198 return (u32)(cdb[6] << 24) + (cdb[7] << 16) + (cdb[8] << 8) + cdb[9]; 199 } 200 201 static inline u32 transport_get_sectors_16(unsigned char *cdb) 202 { 203 return (u32)(cdb[10] << 24) + (cdb[11] << 16) + 204 (cdb[12] << 8) + cdb[13]; 205 } 206 207 /* 208 * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants 209 */ 210 static inline u32 transport_get_sectors_32(unsigned char *cdb) 211 { 212 return (u32)(cdb[28] << 24) + (cdb[29] << 16) + 213 (cdb[30] << 8) + cdb[31]; 214 215 } 216 217 static inline u32 transport_lba_21(unsigned char *cdb) 218 { 219 return ((cdb[1] & 0x1f) << 16) | (cdb[2] << 8) | cdb[3]; 220 } 221 222 static inline u32 transport_lba_32(unsigned char *cdb) 223 { 224 return (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5]; 225 } 226 227 static inline unsigned long long transport_lba_64(unsigned char *cdb) 228 { 229 unsigned int __v1, __v2; 230 231 __v1 = (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5]; 232 __v2 = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9]; 233 234 return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32; 235 } 236 237 /* 238 * For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs 239 */ 240 static inline unsigned long long transport_lba_64_ext(unsigned char *cdb) 241 { 242 unsigned int __v1, __v2; 243 244 __v1 = (cdb[12] << 24) | (cdb[13] << 16) | (cdb[14] << 8) | cdb[15]; 245 __v2 = (cdb[16] << 24) | (cdb[17] << 16) | (cdb[18] << 8) | cdb[19]; 246 247 return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32; 248 } 249 250 static sense_reason_t 251 sbc_setup_write_same(struct se_cmd *cmd, unsigned char *flags, struct sbc_ops *ops) 252 { 253 unsigned int sectors = sbc_get_write_same_sectors(cmd); 254 255 if ((flags[0] & 0x04) || (flags[0] & 0x02)) { 256 pr_err("WRITE_SAME PBDATA and LBDATA" 257 " bits not supported for Block Discard" 258 " Emulation\n"); 259 return TCM_UNSUPPORTED_SCSI_OPCODE; 260 } 261 if (sectors > cmd->se_dev->dev_attrib.max_write_same_len) { 262 pr_warn("WRITE_SAME sectors: %u exceeds max_write_same_len: %u\n", 263 sectors, cmd->se_dev->dev_attrib.max_write_same_len); 264 return TCM_INVALID_CDB_FIELD; 265 } 266 /* 267 * Special case for WRITE_SAME w/ UNMAP=1 that ends up getting 268 * translated into block discard requests within backend code. 269 */ 270 if (flags[0] & 0x08) { 271 if (!ops->execute_write_same_unmap) 272 return TCM_UNSUPPORTED_SCSI_OPCODE; 273 274 cmd->execute_cmd = ops->execute_write_same_unmap; 275 return 0; 276 } 277 if (!ops->execute_write_same) 278 return TCM_UNSUPPORTED_SCSI_OPCODE; 279 280 cmd->execute_cmd = ops->execute_write_same; 281 return 0; 282 } 283 284 static sense_reason_t xdreadwrite_callback(struct se_cmd *cmd) 285 { 286 unsigned char *buf, *addr; 287 struct scatterlist *sg; 288 unsigned int offset; 289 sense_reason_t ret = TCM_NO_SENSE; 290 int i, count; 291 /* 292 * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command 293 * 294 * 1) read the specified logical block(s); 295 * 2) transfer logical blocks from the data-out buffer; 296 * 3) XOR the logical blocks transferred from the data-out buffer with 297 * the logical blocks read, storing the resulting XOR data in a buffer; 298 * 4) if the DISABLE WRITE bit is set to zero, then write the logical 299 * blocks transferred from the data-out buffer; and 300 * 5) transfer the resulting XOR data to the data-in buffer. 301 */ 302 buf = kmalloc(cmd->data_length, GFP_KERNEL); 303 if (!buf) { 304 pr_err("Unable to allocate xor_callback buf\n"); 305 return TCM_OUT_OF_RESOURCES; 306 } 307 /* 308 * Copy the scatterlist WRITE buffer located at cmd->t_data_sg 309 * into the locally allocated *buf 310 */ 311 sg_copy_to_buffer(cmd->t_data_sg, 312 cmd->t_data_nents, 313 buf, 314 cmd->data_length); 315 316 /* 317 * Now perform the XOR against the BIDI read memory located at 318 * cmd->t_mem_bidi_list 319 */ 320 321 offset = 0; 322 for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) { 323 addr = kmap_atomic(sg_page(sg)); 324 if (!addr) { 325 ret = TCM_OUT_OF_RESOURCES; 326 goto out; 327 } 328 329 for (i = 0; i < sg->length; i++) 330 *(addr + sg->offset + i) ^= *(buf + offset + i); 331 332 offset += sg->length; 333 kunmap_atomic(addr); 334 } 335 336 out: 337 kfree(buf); 338 return ret; 339 } 340 341 static sense_reason_t 342 sbc_execute_rw(struct se_cmd *cmd) 343 { 344 return cmd->execute_rw(cmd, cmd->t_data_sg, cmd->t_data_nents, 345 cmd->data_direction); 346 } 347 348 static sense_reason_t compare_and_write_post(struct se_cmd *cmd) 349 { 350 struct se_device *dev = cmd->se_dev; 351 352 /* 353 * Only set SCF_COMPARE_AND_WRITE_POST to force a response fall-through 354 * within target_complete_ok_work() if the command was successfully 355 * sent to the backend driver. 356 */ 357 spin_lock_irq(&cmd->t_state_lock); 358 if ((cmd->transport_state & CMD_T_SENT) && !cmd->scsi_status) 359 cmd->se_cmd_flags |= SCF_COMPARE_AND_WRITE_POST; 360 spin_unlock_irq(&cmd->t_state_lock); 361 362 /* 363 * Unlock ->caw_sem originally obtained during sbc_compare_and_write() 364 * before the original READ I/O submission. 365 */ 366 up(&dev->caw_sem); 367 368 return TCM_NO_SENSE; 369 } 370 371 static sense_reason_t compare_and_write_callback(struct se_cmd *cmd) 372 { 373 struct se_device *dev = cmd->se_dev; 374 struct scatterlist *write_sg = NULL, *sg; 375 unsigned char *buf, *addr; 376 struct sg_mapping_iter m; 377 unsigned int offset = 0, len; 378 unsigned int nlbas = cmd->t_task_nolb; 379 unsigned int block_size = dev->dev_attrib.block_size; 380 unsigned int compare_len = (nlbas * block_size); 381 sense_reason_t ret = TCM_NO_SENSE; 382 int rc, i; 383 384 /* 385 * Handle early failure in transport_generic_request_failure(), 386 * which will not have taken ->caw_mutex yet.. 387 */ 388 if (!cmd->t_data_sg || !cmd->t_bidi_data_sg) 389 return TCM_NO_SENSE; 390 391 buf = kzalloc(cmd->data_length, GFP_KERNEL); 392 if (!buf) { 393 pr_err("Unable to allocate compare_and_write buf\n"); 394 ret = TCM_OUT_OF_RESOURCES; 395 goto out; 396 } 397 398 write_sg = kzalloc(sizeof(struct scatterlist) * cmd->t_data_nents, 399 GFP_KERNEL); 400 if (!write_sg) { 401 pr_err("Unable to allocate compare_and_write sg\n"); 402 ret = TCM_OUT_OF_RESOURCES; 403 goto out; 404 } 405 /* 406 * Setup verify and write data payloads from total NumberLBAs. 407 */ 408 rc = sg_copy_to_buffer(cmd->t_data_sg, cmd->t_data_nents, buf, 409 cmd->data_length); 410 if (!rc) { 411 pr_err("sg_copy_to_buffer() failed for compare_and_write\n"); 412 ret = TCM_OUT_OF_RESOURCES; 413 goto out; 414 } 415 /* 416 * Compare against SCSI READ payload against verify payload 417 */ 418 for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, i) { 419 addr = (unsigned char *)kmap_atomic(sg_page(sg)); 420 if (!addr) { 421 ret = TCM_OUT_OF_RESOURCES; 422 goto out; 423 } 424 425 len = min(sg->length, compare_len); 426 427 if (memcmp(addr, buf + offset, len)) { 428 pr_warn("Detected MISCOMPARE for addr: %p buf: %p\n", 429 addr, buf + offset); 430 kunmap_atomic(addr); 431 goto miscompare; 432 } 433 kunmap_atomic(addr); 434 435 offset += len; 436 compare_len -= len; 437 if (!compare_len) 438 break; 439 } 440 441 i = 0; 442 len = cmd->t_task_nolb * block_size; 443 sg_miter_start(&m, cmd->t_data_sg, cmd->t_data_nents, SG_MITER_TO_SG); 444 /* 445 * Currently assumes NoLB=1 and SGLs are PAGE_SIZE.. 446 */ 447 while (len) { 448 sg_miter_next(&m); 449 450 if (block_size < PAGE_SIZE) { 451 sg_set_page(&write_sg[i], m.page, block_size, 452 block_size); 453 } else { 454 sg_miter_next(&m); 455 sg_set_page(&write_sg[i], m.page, block_size, 456 0); 457 } 458 len -= block_size; 459 i++; 460 } 461 sg_miter_stop(&m); 462 /* 463 * Save the original SGL + nents values before updating to new 464 * assignments, to be released in transport_free_pages() -> 465 * transport_reset_sgl_orig() 466 */ 467 cmd->t_data_sg_orig = cmd->t_data_sg; 468 cmd->t_data_sg = write_sg; 469 cmd->t_data_nents_orig = cmd->t_data_nents; 470 cmd->t_data_nents = 1; 471 472 cmd->sam_task_attr = MSG_HEAD_TAG; 473 cmd->transport_complete_callback = compare_and_write_post; 474 /* 475 * Now reset ->execute_cmd() to the normal sbc_execute_rw() handler 476 * for submitting the adjusted SGL to write instance user-data. 477 */ 478 cmd->execute_cmd = sbc_execute_rw; 479 480 spin_lock_irq(&cmd->t_state_lock); 481 cmd->t_state = TRANSPORT_PROCESSING; 482 cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT; 483 spin_unlock_irq(&cmd->t_state_lock); 484 485 __target_execute_cmd(cmd); 486 487 kfree(buf); 488 return ret; 489 490 miscompare: 491 pr_warn("Target/%s: Send MISCOMPARE check condition and sense\n", 492 dev->transport->name); 493 ret = TCM_MISCOMPARE_VERIFY; 494 out: 495 /* 496 * In the MISCOMPARE or failure case, unlock ->caw_sem obtained in 497 * sbc_compare_and_write() before the original READ I/O submission. 498 */ 499 up(&dev->caw_sem); 500 kfree(write_sg); 501 kfree(buf); 502 return ret; 503 } 504 505 static sense_reason_t 506 sbc_compare_and_write(struct se_cmd *cmd) 507 { 508 struct se_device *dev = cmd->se_dev; 509 sense_reason_t ret; 510 int rc; 511 /* 512 * Submit the READ first for COMPARE_AND_WRITE to perform the 513 * comparision using SGLs at cmd->t_bidi_data_sg.. 514 */ 515 rc = down_interruptible(&dev->caw_sem); 516 if ((rc != 0) || signal_pending(current)) { 517 cmd->transport_complete_callback = NULL; 518 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 519 } 520 /* 521 * Reset cmd->data_length to individual block_size in order to not 522 * confuse backend drivers that depend on this value matching the 523 * size of the I/O being submitted. 524 */ 525 cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size; 526 527 ret = cmd->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents, 528 DMA_FROM_DEVICE); 529 if (ret) { 530 cmd->transport_complete_callback = NULL; 531 up(&dev->caw_sem); 532 return ret; 533 } 534 /* 535 * Unlock of dev->caw_sem to occur in compare_and_write_callback() 536 * upon MISCOMPARE, or in compare_and_write_done() upon completion 537 * of WRITE instance user-data. 538 */ 539 return TCM_NO_SENSE; 540 } 541 542 sense_reason_t 543 sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops) 544 { 545 struct se_device *dev = cmd->se_dev; 546 unsigned char *cdb = cmd->t_task_cdb; 547 unsigned int size; 548 u32 sectors = 0; 549 sense_reason_t ret; 550 551 switch (cdb[0]) { 552 case READ_6: 553 sectors = transport_get_sectors_6(cdb); 554 cmd->t_task_lba = transport_lba_21(cdb); 555 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 556 cmd->execute_rw = ops->execute_rw; 557 cmd->execute_cmd = sbc_execute_rw; 558 break; 559 case READ_10: 560 sectors = transport_get_sectors_10(cdb); 561 cmd->t_task_lba = transport_lba_32(cdb); 562 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 563 cmd->execute_rw = ops->execute_rw; 564 cmd->execute_cmd = sbc_execute_rw; 565 break; 566 case READ_12: 567 sectors = transport_get_sectors_12(cdb); 568 cmd->t_task_lba = transport_lba_32(cdb); 569 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 570 cmd->execute_rw = ops->execute_rw; 571 cmd->execute_cmd = sbc_execute_rw; 572 break; 573 case READ_16: 574 sectors = transport_get_sectors_16(cdb); 575 cmd->t_task_lba = transport_lba_64(cdb); 576 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 577 cmd->execute_rw = ops->execute_rw; 578 cmd->execute_cmd = sbc_execute_rw; 579 break; 580 case WRITE_6: 581 sectors = transport_get_sectors_6(cdb); 582 cmd->t_task_lba = transport_lba_21(cdb); 583 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 584 cmd->execute_rw = ops->execute_rw; 585 cmd->execute_cmd = sbc_execute_rw; 586 break; 587 case WRITE_10: 588 case WRITE_VERIFY: 589 sectors = transport_get_sectors_10(cdb); 590 cmd->t_task_lba = transport_lba_32(cdb); 591 if (cdb[1] & 0x8) 592 cmd->se_cmd_flags |= SCF_FUA; 593 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 594 cmd->execute_rw = ops->execute_rw; 595 cmd->execute_cmd = sbc_execute_rw; 596 break; 597 case WRITE_12: 598 sectors = transport_get_sectors_12(cdb); 599 cmd->t_task_lba = transport_lba_32(cdb); 600 if (cdb[1] & 0x8) 601 cmd->se_cmd_flags |= SCF_FUA; 602 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 603 cmd->execute_rw = ops->execute_rw; 604 cmd->execute_cmd = sbc_execute_rw; 605 break; 606 case WRITE_16: 607 sectors = transport_get_sectors_16(cdb); 608 cmd->t_task_lba = transport_lba_64(cdb); 609 if (cdb[1] & 0x8) 610 cmd->se_cmd_flags |= SCF_FUA; 611 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 612 cmd->execute_rw = ops->execute_rw; 613 cmd->execute_cmd = sbc_execute_rw; 614 break; 615 case XDWRITEREAD_10: 616 if (cmd->data_direction != DMA_TO_DEVICE || 617 !(cmd->se_cmd_flags & SCF_BIDI)) 618 return TCM_INVALID_CDB_FIELD; 619 sectors = transport_get_sectors_10(cdb); 620 621 cmd->t_task_lba = transport_lba_32(cdb); 622 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 623 624 /* 625 * Setup BIDI XOR callback to be run after I/O completion. 626 */ 627 cmd->execute_rw = ops->execute_rw; 628 cmd->execute_cmd = sbc_execute_rw; 629 cmd->transport_complete_callback = &xdreadwrite_callback; 630 if (cdb[1] & 0x8) 631 cmd->se_cmd_flags |= SCF_FUA; 632 break; 633 case VARIABLE_LENGTH_CMD: 634 { 635 u16 service_action = get_unaligned_be16(&cdb[8]); 636 switch (service_action) { 637 case XDWRITEREAD_32: 638 sectors = transport_get_sectors_32(cdb); 639 640 /* 641 * Use WRITE_32 and READ_32 opcodes for the emulated 642 * XDWRITE_READ_32 logic. 643 */ 644 cmd->t_task_lba = transport_lba_64_ext(cdb); 645 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; 646 647 /* 648 * Setup BIDI XOR callback to be run during after I/O 649 * completion. 650 */ 651 cmd->execute_rw = ops->execute_rw; 652 cmd->execute_cmd = sbc_execute_rw; 653 cmd->transport_complete_callback = &xdreadwrite_callback; 654 if (cdb[1] & 0x8) 655 cmd->se_cmd_flags |= SCF_FUA; 656 break; 657 case WRITE_SAME_32: 658 sectors = transport_get_sectors_32(cdb); 659 if (!sectors) { 660 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not" 661 " supported\n"); 662 return TCM_INVALID_CDB_FIELD; 663 } 664 665 size = sbc_get_size(cmd, 1); 666 cmd->t_task_lba = get_unaligned_be64(&cdb[12]); 667 668 ret = sbc_setup_write_same(cmd, &cdb[10], ops); 669 if (ret) 670 return ret; 671 break; 672 default: 673 pr_err("VARIABLE_LENGTH_CMD service action" 674 " 0x%04x not supported\n", service_action); 675 return TCM_UNSUPPORTED_SCSI_OPCODE; 676 } 677 break; 678 } 679 case COMPARE_AND_WRITE: 680 sectors = cdb[13]; 681 /* 682 * Currently enforce COMPARE_AND_WRITE for a single sector 683 */ 684 if (sectors > 1) { 685 pr_err("COMPARE_AND_WRITE contains NoLB: %u greater" 686 " than 1\n", sectors); 687 return TCM_INVALID_CDB_FIELD; 688 } 689 /* 690 * Double size because we have two buffers, note that 691 * zero is not an error.. 692 */ 693 size = 2 * sbc_get_size(cmd, sectors); 694 cmd->t_task_lba = get_unaligned_be64(&cdb[2]); 695 cmd->t_task_nolb = sectors; 696 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE; 697 cmd->execute_rw = ops->execute_rw; 698 cmd->execute_cmd = sbc_compare_and_write; 699 cmd->transport_complete_callback = compare_and_write_callback; 700 break; 701 case READ_CAPACITY: 702 size = READ_CAP_LEN; 703 cmd->execute_cmd = sbc_emulate_readcapacity; 704 break; 705 case SERVICE_ACTION_IN: 706 switch (cmd->t_task_cdb[1] & 0x1f) { 707 case SAI_READ_CAPACITY_16: 708 cmd->execute_cmd = sbc_emulate_readcapacity_16; 709 break; 710 default: 711 pr_err("Unsupported SA: 0x%02x\n", 712 cmd->t_task_cdb[1] & 0x1f); 713 return TCM_INVALID_CDB_FIELD; 714 } 715 size = (cdb[10] << 24) | (cdb[11] << 16) | 716 (cdb[12] << 8) | cdb[13]; 717 break; 718 case SYNCHRONIZE_CACHE: 719 case SYNCHRONIZE_CACHE_16: 720 if (!ops->execute_sync_cache) { 721 size = 0; 722 cmd->execute_cmd = sbc_emulate_noop; 723 break; 724 } 725 726 /* 727 * Extract LBA and range to be flushed for emulated SYNCHRONIZE_CACHE 728 */ 729 if (cdb[0] == SYNCHRONIZE_CACHE) { 730 sectors = transport_get_sectors_10(cdb); 731 cmd->t_task_lba = transport_lba_32(cdb); 732 } else { 733 sectors = transport_get_sectors_16(cdb); 734 cmd->t_task_lba = transport_lba_64(cdb); 735 } 736 737 size = sbc_get_size(cmd, sectors); 738 739 /* 740 * Check to ensure that LBA + Range does not exceed past end of 741 * device for IBLOCK and FILEIO ->do_sync_cache() backend calls 742 */ 743 if (cmd->t_task_lba || sectors) { 744 if (sbc_check_valid_sectors(cmd) < 0) 745 return TCM_ADDRESS_OUT_OF_RANGE; 746 } 747 cmd->execute_cmd = ops->execute_sync_cache; 748 break; 749 case UNMAP: 750 if (!ops->execute_unmap) 751 return TCM_UNSUPPORTED_SCSI_OPCODE; 752 753 size = get_unaligned_be16(&cdb[7]); 754 cmd->execute_cmd = ops->execute_unmap; 755 break; 756 case WRITE_SAME_16: 757 sectors = transport_get_sectors_16(cdb); 758 if (!sectors) { 759 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n"); 760 return TCM_INVALID_CDB_FIELD; 761 } 762 763 size = sbc_get_size(cmd, 1); 764 cmd->t_task_lba = get_unaligned_be64(&cdb[2]); 765 766 ret = sbc_setup_write_same(cmd, &cdb[1], ops); 767 if (ret) 768 return ret; 769 break; 770 case WRITE_SAME: 771 sectors = transport_get_sectors_10(cdb); 772 if (!sectors) { 773 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n"); 774 return TCM_INVALID_CDB_FIELD; 775 } 776 777 size = sbc_get_size(cmd, 1); 778 cmd->t_task_lba = get_unaligned_be32(&cdb[2]); 779 780 /* 781 * Follow sbcr26 with WRITE_SAME (10) and check for the existence 782 * of byte 1 bit 3 UNMAP instead of original reserved field 783 */ 784 ret = sbc_setup_write_same(cmd, &cdb[1], ops); 785 if (ret) 786 return ret; 787 break; 788 case VERIFY: 789 size = 0; 790 cmd->execute_cmd = sbc_emulate_noop; 791 break; 792 case REZERO_UNIT: 793 case SEEK_6: 794 case SEEK_10: 795 /* 796 * There are still clients out there which use these old SCSI-2 797 * commands. This mainly happens when running VMs with legacy 798 * guest systems, connected via SCSI command pass-through to 799 * iSCSI targets. Make them happy and return status GOOD. 800 */ 801 size = 0; 802 cmd->execute_cmd = sbc_emulate_noop; 803 break; 804 default: 805 ret = spc_parse_cdb(cmd, &size); 806 if (ret) 807 return ret; 808 } 809 810 /* reject any command that we don't have a handler for */ 811 if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) && !cmd->execute_cmd) 812 return TCM_UNSUPPORTED_SCSI_OPCODE; 813 814 if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) { 815 unsigned long long end_lba; 816 817 if (sectors > dev->dev_attrib.fabric_max_sectors) { 818 printk_ratelimited(KERN_ERR "SCSI OP %02xh with too" 819 " big sectors %u exceeds fabric_max_sectors:" 820 " %u\n", cdb[0], sectors, 821 dev->dev_attrib.fabric_max_sectors); 822 return TCM_INVALID_CDB_FIELD; 823 } 824 if (sectors > dev->dev_attrib.hw_max_sectors) { 825 printk_ratelimited(KERN_ERR "SCSI OP %02xh with too" 826 " big sectors %u exceeds backend hw_max_sectors:" 827 " %u\n", cdb[0], sectors, 828 dev->dev_attrib.hw_max_sectors); 829 return TCM_INVALID_CDB_FIELD; 830 } 831 832 end_lba = dev->transport->get_blocks(dev) + 1; 833 if (cmd->t_task_lba + sectors > end_lba) { 834 pr_err("cmd exceeds last lba %llu " 835 "(lba %llu, sectors %u)\n", 836 end_lba, cmd->t_task_lba, sectors); 837 return TCM_ADDRESS_OUT_OF_RANGE; 838 } 839 840 if (!(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) 841 size = sbc_get_size(cmd, sectors); 842 } 843 844 return target_cmd_size_check(cmd, size); 845 } 846 EXPORT_SYMBOL(sbc_parse_cdb); 847 848 u32 sbc_get_device_type(struct se_device *dev) 849 { 850 return TYPE_DISK; 851 } 852 EXPORT_SYMBOL(sbc_get_device_type); 853 854 sense_reason_t 855 sbc_execute_unmap(struct se_cmd *cmd, 856 sense_reason_t (*do_unmap_fn)(struct se_cmd *, void *, 857 sector_t, sector_t), 858 void *priv) 859 { 860 struct se_device *dev = cmd->se_dev; 861 unsigned char *buf, *ptr = NULL; 862 sector_t lba; 863 int size; 864 u32 range; 865 sense_reason_t ret = 0; 866 int dl, bd_dl; 867 868 /* We never set ANC_SUP */ 869 if (cmd->t_task_cdb[1]) 870 return TCM_INVALID_CDB_FIELD; 871 872 if (cmd->data_length == 0) { 873 target_complete_cmd(cmd, SAM_STAT_GOOD); 874 return 0; 875 } 876 877 if (cmd->data_length < 8) { 878 pr_warn("UNMAP parameter list length %u too small\n", 879 cmd->data_length); 880 return TCM_PARAMETER_LIST_LENGTH_ERROR; 881 } 882 883 buf = transport_kmap_data_sg(cmd); 884 if (!buf) 885 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 886 887 dl = get_unaligned_be16(&buf[0]); 888 bd_dl = get_unaligned_be16(&buf[2]); 889 890 size = cmd->data_length - 8; 891 if (bd_dl > size) 892 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n", 893 cmd->data_length, bd_dl); 894 else 895 size = bd_dl; 896 897 if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) { 898 ret = TCM_INVALID_PARAMETER_LIST; 899 goto err; 900 } 901 902 /* First UNMAP block descriptor starts at 8 byte offset */ 903 ptr = &buf[8]; 904 pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u" 905 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr); 906 907 while (size >= 16) { 908 lba = get_unaligned_be64(&ptr[0]); 909 range = get_unaligned_be32(&ptr[8]); 910 pr_debug("UNMAP: Using lba: %llu and range: %u\n", 911 (unsigned long long)lba, range); 912 913 if (range > dev->dev_attrib.max_unmap_lba_count) { 914 ret = TCM_INVALID_PARAMETER_LIST; 915 goto err; 916 } 917 918 if (lba + range > dev->transport->get_blocks(dev) + 1) { 919 ret = TCM_ADDRESS_OUT_OF_RANGE; 920 goto err; 921 } 922 923 ret = do_unmap_fn(cmd, priv, lba, range); 924 if (ret) 925 goto err; 926 927 ptr += 16; 928 size -= 16; 929 } 930 931 err: 932 transport_kunmap_data_sg(cmd); 933 if (!ret) 934 target_complete_cmd(cmd, GOOD); 935 return ret; 936 } 937 EXPORT_SYMBOL(sbc_execute_unmap); 938