1 /* 2 * SCSI Zoned Block commands 3 * 4 * Copyright (C) 2014-2015 SUSE Linux GmbH 5 * Written by: Hannes Reinecke <hare@suse.de> 6 * Modified by: Damien Le Moal <damien.lemoal@hgst.com> 7 * Modified by: Shaun Tancheff <shaun.tancheff@seagate.com> 8 * 9 * This program is free software; you can redistribute it and/or 10 * modify it under the terms of the GNU General Public License version 11 * 2 as published by the Free Software Foundation. 12 * 13 * This program is distributed in the hope that it will be useful, but 14 * WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * 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; see the file COPYING. If not, write to 20 * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, 21 * USA. 22 * 23 */ 24 25 #include <linux/blkdev.h> 26 27 #include <asm/unaligned.h> 28 29 #include <scsi/scsi.h> 30 #include <scsi/scsi_cmnd.h> 31 #include <scsi/scsi_dbg.h> 32 #include <scsi/scsi_device.h> 33 #include <scsi/scsi_driver.h> 34 #include <scsi/scsi_host.h> 35 #include <scsi/scsi_eh.h> 36 37 #include "sd.h" 38 #include "scsi_priv.h" 39 40 enum zbc_zone_type { 41 ZBC_ZONE_TYPE_CONV = 0x1, 42 ZBC_ZONE_TYPE_SEQWRITE_REQ, 43 ZBC_ZONE_TYPE_SEQWRITE_PREF, 44 ZBC_ZONE_TYPE_RESERVED, 45 }; 46 47 enum zbc_zone_cond { 48 ZBC_ZONE_COND_NO_WP, 49 ZBC_ZONE_COND_EMPTY, 50 ZBC_ZONE_COND_IMP_OPEN, 51 ZBC_ZONE_COND_EXP_OPEN, 52 ZBC_ZONE_COND_CLOSED, 53 ZBC_ZONE_COND_READONLY = 0xd, 54 ZBC_ZONE_COND_FULL, 55 ZBC_ZONE_COND_OFFLINE, 56 }; 57 58 /** 59 * Convert a zone descriptor to a zone struct. 60 */ 61 static void sd_zbc_parse_report(struct scsi_disk *sdkp, 62 u8 *buf, 63 struct blk_zone *zone) 64 { 65 struct scsi_device *sdp = sdkp->device; 66 67 memset(zone, 0, sizeof(struct blk_zone)); 68 69 zone->type = buf[0] & 0x0f; 70 zone->cond = (buf[1] >> 4) & 0xf; 71 if (buf[1] & 0x01) 72 zone->reset = 1; 73 if (buf[1] & 0x02) 74 zone->non_seq = 1; 75 76 zone->len = logical_to_sectors(sdp, get_unaligned_be64(&buf[8])); 77 zone->start = logical_to_sectors(sdp, get_unaligned_be64(&buf[16])); 78 zone->wp = logical_to_sectors(sdp, get_unaligned_be64(&buf[24])); 79 if (zone->type != ZBC_ZONE_TYPE_CONV && 80 zone->cond == ZBC_ZONE_COND_FULL) 81 zone->wp = zone->start + zone->len; 82 } 83 84 /** 85 * Issue a REPORT ZONES scsi command. 86 */ 87 static int sd_zbc_report_zones(struct scsi_disk *sdkp, unsigned char *buf, 88 unsigned int buflen, sector_t lba) 89 { 90 struct scsi_device *sdp = sdkp->device; 91 const int timeout = sdp->request_queue->rq_timeout; 92 struct scsi_sense_hdr sshdr; 93 unsigned char cmd[16]; 94 unsigned int rep_len; 95 int result; 96 97 memset(cmd, 0, 16); 98 cmd[0] = ZBC_IN; 99 cmd[1] = ZI_REPORT_ZONES; 100 put_unaligned_be64(lba, &cmd[2]); 101 put_unaligned_be32(buflen, &cmd[10]); 102 memset(buf, 0, buflen); 103 104 result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE, 105 buf, buflen, &sshdr, 106 timeout, SD_MAX_RETRIES, NULL); 107 if (result) { 108 sd_printk(KERN_ERR, sdkp, 109 "REPORT ZONES lba %llu failed with %d/%d\n", 110 (unsigned long long)lba, 111 host_byte(result), driver_byte(result)); 112 return -EIO; 113 } 114 115 rep_len = get_unaligned_be32(&buf[0]); 116 if (rep_len < 64) { 117 sd_printk(KERN_ERR, sdkp, 118 "REPORT ZONES report invalid length %u\n", 119 rep_len); 120 return -EIO; 121 } 122 123 return 0; 124 } 125 126 int sd_zbc_setup_report_cmnd(struct scsi_cmnd *cmd) 127 { 128 struct request *rq = cmd->request; 129 struct scsi_disk *sdkp = scsi_disk(rq->rq_disk); 130 sector_t lba, sector = blk_rq_pos(rq); 131 unsigned int nr_bytes = blk_rq_bytes(rq); 132 int ret; 133 134 WARN_ON(nr_bytes == 0); 135 136 if (!sd_is_zoned(sdkp)) 137 /* Not a zoned device */ 138 return BLKPREP_KILL; 139 140 ret = scsi_init_io(cmd); 141 if (ret != BLKPREP_OK) 142 return ret; 143 144 cmd->cmd_len = 16; 145 memset(cmd->cmnd, 0, cmd->cmd_len); 146 cmd->cmnd[0] = ZBC_IN; 147 cmd->cmnd[1] = ZI_REPORT_ZONES; 148 lba = sectors_to_logical(sdkp->device, sector); 149 put_unaligned_be64(lba, &cmd->cmnd[2]); 150 put_unaligned_be32(nr_bytes, &cmd->cmnd[10]); 151 /* Do partial report for speeding things up */ 152 cmd->cmnd[14] = ZBC_REPORT_ZONE_PARTIAL; 153 154 cmd->sc_data_direction = DMA_FROM_DEVICE; 155 cmd->sdb.length = nr_bytes; 156 cmd->transfersize = sdkp->device->sector_size; 157 cmd->allowed = 0; 158 159 /* 160 * Report may return less bytes than requested. Make sure 161 * to report completion on the entire initial request. 162 */ 163 rq->__data_len = nr_bytes; 164 165 return BLKPREP_OK; 166 } 167 168 static void sd_zbc_report_zones_complete(struct scsi_cmnd *scmd, 169 unsigned int good_bytes) 170 { 171 struct request *rq = scmd->request; 172 struct scsi_disk *sdkp = scsi_disk(rq->rq_disk); 173 struct sg_mapping_iter miter; 174 struct blk_zone_report_hdr hdr; 175 struct blk_zone zone; 176 unsigned int offset, bytes = 0; 177 unsigned long flags; 178 u8 *buf; 179 180 if (good_bytes < 64) 181 return; 182 183 memset(&hdr, 0, sizeof(struct blk_zone_report_hdr)); 184 185 sg_miter_start(&miter, scsi_sglist(scmd), scsi_sg_count(scmd), 186 SG_MITER_TO_SG | SG_MITER_ATOMIC); 187 188 local_irq_save(flags); 189 while (sg_miter_next(&miter) && bytes < good_bytes) { 190 191 buf = miter.addr; 192 offset = 0; 193 194 if (bytes == 0) { 195 /* Set the report header */ 196 hdr.nr_zones = min_t(unsigned int, 197 (good_bytes - 64) / 64, 198 get_unaligned_be32(&buf[0]) / 64); 199 memcpy(buf, &hdr, sizeof(struct blk_zone_report_hdr)); 200 offset += 64; 201 bytes += 64; 202 } 203 204 /* Parse zone descriptors */ 205 while (offset < miter.length && hdr.nr_zones) { 206 WARN_ON(offset > miter.length); 207 buf = miter.addr + offset; 208 sd_zbc_parse_report(sdkp, buf, &zone); 209 memcpy(buf, &zone, sizeof(struct blk_zone)); 210 offset += 64; 211 bytes += 64; 212 hdr.nr_zones--; 213 } 214 215 if (!hdr.nr_zones) 216 break; 217 218 } 219 sg_miter_stop(&miter); 220 local_irq_restore(flags); 221 } 222 223 static inline sector_t sd_zbc_zone_sectors(struct scsi_disk *sdkp) 224 { 225 return logical_to_sectors(sdkp->device, sdkp->zone_blocks); 226 } 227 228 static inline unsigned int sd_zbc_zone_no(struct scsi_disk *sdkp, 229 sector_t sector) 230 { 231 return sectors_to_logical(sdkp->device, sector) >> sdkp->zone_shift; 232 } 233 234 int sd_zbc_setup_reset_cmnd(struct scsi_cmnd *cmd) 235 { 236 struct request *rq = cmd->request; 237 struct scsi_disk *sdkp = scsi_disk(rq->rq_disk); 238 sector_t sector = blk_rq_pos(rq); 239 sector_t block = sectors_to_logical(sdkp->device, sector); 240 unsigned int zno = block >> sdkp->zone_shift; 241 242 if (!sd_is_zoned(sdkp)) 243 /* Not a zoned device */ 244 return BLKPREP_KILL; 245 246 if (sdkp->device->changed) 247 return BLKPREP_KILL; 248 249 if (sector & (sd_zbc_zone_sectors(sdkp) - 1)) 250 /* Unaligned request */ 251 return BLKPREP_KILL; 252 253 /* Do not allow concurrent reset and writes */ 254 if (sdkp->zones_wlock && 255 test_and_set_bit(zno, sdkp->zones_wlock)) 256 return BLKPREP_DEFER; 257 258 cmd->cmd_len = 16; 259 memset(cmd->cmnd, 0, cmd->cmd_len); 260 cmd->cmnd[0] = ZBC_OUT; 261 cmd->cmnd[1] = ZO_RESET_WRITE_POINTER; 262 put_unaligned_be64(block, &cmd->cmnd[2]); 263 264 rq->timeout = SD_TIMEOUT; 265 cmd->sc_data_direction = DMA_NONE; 266 cmd->transfersize = 0; 267 cmd->allowed = 0; 268 269 return BLKPREP_OK; 270 } 271 272 int sd_zbc_setup_write_cmnd(struct scsi_cmnd *cmd) 273 { 274 struct request *rq = cmd->request; 275 struct scsi_disk *sdkp = scsi_disk(rq->rq_disk); 276 sector_t sector = blk_rq_pos(rq); 277 sector_t zone_sectors = sd_zbc_zone_sectors(sdkp); 278 unsigned int zno = sd_zbc_zone_no(sdkp, sector); 279 280 /* 281 * Note: Checks of the alignment of the write command on 282 * logical blocks is done in sd.c 283 */ 284 285 /* Do not allow zone boundaries crossing on host-managed drives */ 286 if (blk_queue_zoned_model(sdkp->disk->queue) == BLK_ZONED_HM && 287 (sector & (zone_sectors - 1)) + blk_rq_sectors(rq) > zone_sectors) 288 return BLKPREP_KILL; 289 290 /* 291 * Do not issue more than one write at a time per 292 * zone. This solves write ordering problems due to 293 * the unlocking of the request queue in the dispatch 294 * path in the non scsi-mq case. For scsi-mq, this 295 * also avoids potential write reordering when multiple 296 * threads running on different CPUs write to the same 297 * zone (with a synchronized sequential pattern). 298 */ 299 if (sdkp->zones_wlock && 300 test_and_set_bit(zno, sdkp->zones_wlock)) 301 return BLKPREP_DEFER; 302 303 return BLKPREP_OK; 304 } 305 306 static void sd_zbc_unlock_zone(struct request *rq) 307 { 308 struct scsi_disk *sdkp = scsi_disk(rq->rq_disk); 309 310 if (sdkp->zones_wlock) { 311 unsigned int zno = sd_zbc_zone_no(sdkp, blk_rq_pos(rq)); 312 WARN_ON_ONCE(!test_bit(zno, sdkp->zones_wlock)); 313 clear_bit_unlock(zno, sdkp->zones_wlock); 314 smp_mb__after_atomic(); 315 } 316 } 317 318 void sd_zbc_cancel_write_cmnd(struct scsi_cmnd *cmd) 319 { 320 sd_zbc_unlock_zone(cmd->request); 321 } 322 323 void sd_zbc_complete(struct scsi_cmnd *cmd, 324 unsigned int good_bytes, 325 struct scsi_sense_hdr *sshdr) 326 { 327 int result = cmd->result; 328 struct request *rq = cmd->request; 329 330 switch (req_op(rq)) { 331 case REQ_OP_WRITE: 332 case REQ_OP_WRITE_SAME: 333 case REQ_OP_ZONE_RESET: 334 335 /* Unlock the zone */ 336 sd_zbc_unlock_zone(rq); 337 338 if (!result || 339 sshdr->sense_key != ILLEGAL_REQUEST) 340 break; 341 342 switch (sshdr->asc) { 343 case 0x24: 344 /* 345 * INVALID FIELD IN CDB error: For a zone reset, 346 * this means that a reset of a conventional 347 * zone was attempted. Nothing to worry about in 348 * this case, so be quiet about the error. 349 */ 350 if (req_op(rq) == REQ_OP_ZONE_RESET) 351 rq->rq_flags |= RQF_QUIET; 352 break; 353 case 0x21: 354 /* 355 * INVALID ADDRESS FOR WRITE error: It is unlikely that 356 * retrying write requests failed with any kind of 357 * alignement error will result in success. So don't. 358 */ 359 cmd->allowed = 0; 360 break; 361 } 362 363 break; 364 365 case REQ_OP_ZONE_REPORT: 366 367 if (!result) 368 sd_zbc_report_zones_complete(cmd, good_bytes); 369 break; 370 371 } 372 } 373 374 /** 375 * Read zoned block device characteristics (VPD page B6). 376 */ 377 static int sd_zbc_read_zoned_characteristics(struct scsi_disk *sdkp, 378 unsigned char *buf) 379 { 380 381 if (scsi_get_vpd_page(sdkp->device, 0xb6, buf, 64)) { 382 sd_printk(KERN_NOTICE, sdkp, 383 "Unconstrained-read check failed\n"); 384 return -ENODEV; 385 } 386 387 if (sdkp->device->type != TYPE_ZBC) { 388 /* Host-aware */ 389 sdkp->urswrz = 1; 390 sdkp->zones_optimal_open = get_unaligned_be64(&buf[8]); 391 sdkp->zones_optimal_nonseq = get_unaligned_be64(&buf[12]); 392 sdkp->zones_max_open = 0; 393 } else { 394 /* Host-managed */ 395 sdkp->urswrz = buf[4] & 1; 396 sdkp->zones_optimal_open = 0; 397 sdkp->zones_optimal_nonseq = 0; 398 sdkp->zones_max_open = get_unaligned_be64(&buf[16]); 399 } 400 401 return 0; 402 } 403 404 /** 405 * Check reported capacity. 406 */ 407 static int sd_zbc_check_capacity(struct scsi_disk *sdkp, 408 unsigned char *buf) 409 { 410 sector_t lba; 411 int ret; 412 413 if (sdkp->rc_basis != 0) 414 return 0; 415 416 /* Do a report zone to get the maximum LBA to check capacity */ 417 ret = sd_zbc_report_zones(sdkp, buf, SD_BUF_SIZE, 0); 418 if (ret) 419 return ret; 420 421 /* The max_lba field is the capacity of this device */ 422 lba = get_unaligned_be64(&buf[8]); 423 if (lba + 1 == sdkp->capacity) 424 return 0; 425 426 if (sdkp->first_scan) 427 sd_printk(KERN_WARNING, sdkp, 428 "Changing capacity from %llu to max LBA+1 %llu\n", 429 (unsigned long long)sdkp->capacity, 430 (unsigned long long)lba + 1); 431 sdkp->capacity = lba + 1; 432 433 return 0; 434 } 435 436 #define SD_ZBC_BUF_SIZE 131072 437 438 static int sd_zbc_check_zone_size(struct scsi_disk *sdkp) 439 { 440 u64 zone_blocks; 441 sector_t block = 0; 442 unsigned char *buf; 443 unsigned char *rec; 444 unsigned int buf_len; 445 unsigned int list_length; 446 int ret; 447 u8 same; 448 449 sdkp->zone_blocks = 0; 450 451 /* Get a buffer */ 452 buf = kmalloc(SD_ZBC_BUF_SIZE, GFP_KERNEL); 453 if (!buf) 454 return -ENOMEM; 455 456 /* Do a report zone to get the same field */ 457 ret = sd_zbc_report_zones(sdkp, buf, SD_ZBC_BUF_SIZE, 0); 458 if (ret) { 459 zone_blocks = 0; 460 goto out; 461 } 462 463 same = buf[4] & 0x0f; 464 if (same > 0) { 465 rec = &buf[64]; 466 zone_blocks = get_unaligned_be64(&rec[8]); 467 goto out; 468 } 469 470 /* 471 * Check the size of all zones: all zones must be of 472 * equal size, except the last zone which can be smaller 473 * than other zones. 474 */ 475 do { 476 477 /* Parse REPORT ZONES header */ 478 list_length = get_unaligned_be32(&buf[0]) + 64; 479 rec = buf + 64; 480 if (list_length < SD_ZBC_BUF_SIZE) 481 buf_len = list_length; 482 else 483 buf_len = SD_ZBC_BUF_SIZE; 484 485 /* Parse zone descriptors */ 486 while (rec < buf + buf_len) { 487 zone_blocks = get_unaligned_be64(&rec[8]); 488 if (sdkp->zone_blocks == 0) { 489 sdkp->zone_blocks = zone_blocks; 490 } else if (zone_blocks != sdkp->zone_blocks && 491 (block + zone_blocks < sdkp->capacity 492 || zone_blocks > sdkp->zone_blocks)) { 493 zone_blocks = 0; 494 goto out; 495 } 496 block += zone_blocks; 497 rec += 64; 498 } 499 500 if (block < sdkp->capacity) { 501 ret = sd_zbc_report_zones(sdkp, buf, 502 SD_ZBC_BUF_SIZE, block); 503 if (ret) 504 return ret; 505 } 506 507 } while (block < sdkp->capacity); 508 509 zone_blocks = sdkp->zone_blocks; 510 511 out: 512 kfree(buf); 513 514 if (!zone_blocks) { 515 if (sdkp->first_scan) 516 sd_printk(KERN_NOTICE, sdkp, 517 "Devices with non constant zone " 518 "size are not supported\n"); 519 return -ENODEV; 520 } 521 522 if (!is_power_of_2(zone_blocks)) { 523 if (sdkp->first_scan) 524 sd_printk(KERN_NOTICE, sdkp, 525 "Devices with non power of 2 zone " 526 "size are not supported\n"); 527 return -ENODEV; 528 } 529 530 if (logical_to_sectors(sdkp->device, zone_blocks) > UINT_MAX) { 531 if (sdkp->first_scan) 532 sd_printk(KERN_NOTICE, sdkp, 533 "Zone size too large\n"); 534 return -ENODEV; 535 } 536 537 sdkp->zone_blocks = zone_blocks; 538 539 return 0; 540 } 541 542 static int sd_zbc_setup(struct scsi_disk *sdkp) 543 { 544 545 /* chunk_sectors indicates the zone size */ 546 blk_queue_chunk_sectors(sdkp->disk->queue, 547 logical_to_sectors(sdkp->device, sdkp->zone_blocks)); 548 sdkp->zone_shift = ilog2(sdkp->zone_blocks); 549 sdkp->nr_zones = sdkp->capacity >> sdkp->zone_shift; 550 if (sdkp->capacity & (sdkp->zone_blocks - 1)) 551 sdkp->nr_zones++; 552 553 if (!sdkp->zones_wlock) { 554 sdkp->zones_wlock = kcalloc(BITS_TO_LONGS(sdkp->nr_zones), 555 sizeof(unsigned long), 556 GFP_KERNEL); 557 if (!sdkp->zones_wlock) 558 return -ENOMEM; 559 } 560 561 return 0; 562 } 563 564 int sd_zbc_read_zones(struct scsi_disk *sdkp, 565 unsigned char *buf) 566 { 567 sector_t capacity; 568 int ret = 0; 569 570 if (!sd_is_zoned(sdkp)) 571 /* 572 * Device managed or normal SCSI disk, 573 * no special handling required 574 */ 575 return 0; 576 577 578 /* Get zoned block device characteristics */ 579 ret = sd_zbc_read_zoned_characteristics(sdkp, buf); 580 if (ret) 581 goto err; 582 583 /* 584 * Check for unconstrained reads: host-managed devices with 585 * constrained reads (drives failing read after write pointer) 586 * are not supported. 587 */ 588 if (!sdkp->urswrz) { 589 if (sdkp->first_scan) 590 sd_printk(KERN_NOTICE, sdkp, 591 "constrained reads devices are not supported\n"); 592 ret = -ENODEV; 593 goto err; 594 } 595 596 /* Check capacity */ 597 ret = sd_zbc_check_capacity(sdkp, buf); 598 if (ret) 599 goto err; 600 capacity = logical_to_sectors(sdkp->device, sdkp->capacity); 601 602 /* 603 * Check zone size: only devices with a constant zone size (except 604 * an eventual last runt zone) that is a power of 2 are supported. 605 */ 606 ret = sd_zbc_check_zone_size(sdkp); 607 if (ret) 608 goto err; 609 610 /* The drive satisfies the kernel restrictions: set it up */ 611 ret = sd_zbc_setup(sdkp); 612 if (ret) 613 goto err; 614 615 /* READ16/WRITE16 is mandatory for ZBC disks */ 616 sdkp->device->use_16_for_rw = 1; 617 sdkp->device->use_10_for_rw = 0; 618 619 return 0; 620 621 err: 622 sdkp->capacity = 0; 623 624 return ret; 625 } 626 627 void sd_zbc_remove(struct scsi_disk *sdkp) 628 { 629 kfree(sdkp->zones_wlock); 630 sdkp->zones_wlock = NULL; 631 } 632 633 void sd_zbc_print_zones(struct scsi_disk *sdkp) 634 { 635 if (!sd_is_zoned(sdkp) || !sdkp->capacity) 636 return; 637 638 if (sdkp->capacity & (sdkp->zone_blocks - 1)) 639 sd_printk(KERN_NOTICE, sdkp, 640 "%u zones of %u logical blocks + 1 runt zone\n", 641 sdkp->nr_zones - 1, 642 sdkp->zone_blocks); 643 else 644 sd_printk(KERN_NOTICE, sdkp, 645 "%u zones of %u logical blocks\n", 646 sdkp->nr_zones, 647 sdkp->zone_blocks); 648 } 649