1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/vmalloc.h> 3 #include <linux/bitmap.h> 4 #include "null_blk.h" 5 6 #define CREATE_TRACE_POINTS 7 #include "trace.h" 8 9 #undef pr_fmt 10 #define pr_fmt(fmt) "null_blk: " fmt 11 12 static inline sector_t mb_to_sects(unsigned long mb) 13 { 14 return ((sector_t)mb * SZ_1M) >> SECTOR_SHIFT; 15 } 16 17 static inline unsigned int null_zone_no(struct nullb_device *dev, sector_t sect) 18 { 19 return sect >> ilog2(dev->zone_size_sects); 20 } 21 22 static inline void null_lock_zone_res(struct nullb_device *dev) 23 { 24 if (dev->need_zone_res_mgmt) 25 spin_lock_irq(&dev->zone_res_lock); 26 } 27 28 static inline void null_unlock_zone_res(struct nullb_device *dev) 29 { 30 if (dev->need_zone_res_mgmt) 31 spin_unlock_irq(&dev->zone_res_lock); 32 } 33 34 static inline void null_init_zone_lock(struct nullb_device *dev, 35 struct nullb_zone *zone) 36 { 37 if (!dev->memory_backed) 38 spin_lock_init(&zone->spinlock); 39 else 40 mutex_init(&zone->mutex); 41 } 42 43 static inline void null_lock_zone(struct nullb_device *dev, 44 struct nullb_zone *zone) 45 { 46 if (!dev->memory_backed) 47 spin_lock_irq(&zone->spinlock); 48 else 49 mutex_lock(&zone->mutex); 50 } 51 52 static inline void null_unlock_zone(struct nullb_device *dev, 53 struct nullb_zone *zone) 54 { 55 if (!dev->memory_backed) 56 spin_unlock_irq(&zone->spinlock); 57 else 58 mutex_unlock(&zone->mutex); 59 } 60 61 int null_init_zoned_dev(struct nullb_device *dev, struct request_queue *q) 62 { 63 sector_t dev_capacity_sects, zone_capacity_sects; 64 struct nullb_zone *zone; 65 sector_t sector = 0; 66 unsigned int i; 67 68 if (!is_power_of_2(dev->zone_size)) { 69 pr_err("zone_size must be power-of-two\n"); 70 return -EINVAL; 71 } 72 if (dev->zone_size > dev->size) { 73 pr_err("Zone size larger than device capacity\n"); 74 return -EINVAL; 75 } 76 77 if (!dev->zone_capacity) 78 dev->zone_capacity = dev->zone_size; 79 80 if (dev->zone_capacity > dev->zone_size) { 81 pr_err("zone capacity (%lu MB) larger than zone size (%lu MB)\n", 82 dev->zone_capacity, dev->zone_size); 83 return -EINVAL; 84 } 85 86 zone_capacity_sects = mb_to_sects(dev->zone_capacity); 87 dev_capacity_sects = mb_to_sects(dev->size); 88 dev->zone_size_sects = mb_to_sects(dev->zone_size); 89 dev->nr_zones = round_up(dev_capacity_sects, dev->zone_size_sects) 90 >> ilog2(dev->zone_size_sects); 91 92 dev->zones = kvmalloc_array(dev->nr_zones, sizeof(struct nullb_zone), 93 GFP_KERNEL | __GFP_ZERO); 94 if (!dev->zones) 95 return -ENOMEM; 96 97 spin_lock_init(&dev->zone_res_lock); 98 99 if (dev->zone_nr_conv >= dev->nr_zones) { 100 dev->zone_nr_conv = dev->nr_zones - 1; 101 pr_info("changed the number of conventional zones to %u", 102 dev->zone_nr_conv); 103 } 104 105 /* Max active zones has to be < nbr of seq zones in order to be enforceable */ 106 if (dev->zone_max_active >= dev->nr_zones - dev->zone_nr_conv) { 107 dev->zone_max_active = 0; 108 pr_info("zone_max_active limit disabled, limit >= zone count\n"); 109 } 110 111 /* Max open zones has to be <= max active zones */ 112 if (dev->zone_max_active && dev->zone_max_open > dev->zone_max_active) { 113 dev->zone_max_open = dev->zone_max_active; 114 pr_info("changed the maximum number of open zones to %u\n", 115 dev->nr_zones); 116 } else if (dev->zone_max_open >= dev->nr_zones - dev->zone_nr_conv) { 117 dev->zone_max_open = 0; 118 pr_info("zone_max_open limit disabled, limit >= zone count\n"); 119 } 120 dev->need_zone_res_mgmt = dev->zone_max_active || dev->zone_max_open; 121 dev->imp_close_zone_no = dev->zone_nr_conv; 122 123 for (i = 0; i < dev->zone_nr_conv; i++) { 124 zone = &dev->zones[i]; 125 126 null_init_zone_lock(dev, zone); 127 zone->start = sector; 128 zone->len = dev->zone_size_sects; 129 zone->capacity = zone->len; 130 zone->wp = zone->start + zone->len; 131 zone->type = BLK_ZONE_TYPE_CONVENTIONAL; 132 zone->cond = BLK_ZONE_COND_NOT_WP; 133 134 sector += dev->zone_size_sects; 135 } 136 137 for (i = dev->zone_nr_conv; i < dev->nr_zones; i++) { 138 zone = &dev->zones[i]; 139 140 null_init_zone_lock(dev, zone); 141 zone->start = zone->wp = sector; 142 if (zone->start + dev->zone_size_sects > dev_capacity_sects) 143 zone->len = dev_capacity_sects - zone->start; 144 else 145 zone->len = dev->zone_size_sects; 146 zone->capacity = 147 min_t(sector_t, zone->len, zone_capacity_sects); 148 zone->type = BLK_ZONE_TYPE_SEQWRITE_REQ; 149 zone->cond = BLK_ZONE_COND_EMPTY; 150 151 sector += dev->zone_size_sects; 152 } 153 154 return 0; 155 } 156 157 int null_register_zoned_dev(struct nullb *nullb) 158 { 159 struct nullb_device *dev = nullb->dev; 160 struct request_queue *q = nullb->q; 161 162 disk_set_zoned(nullb->disk, BLK_ZONED_HM); 163 blk_queue_flag_set(QUEUE_FLAG_ZONE_RESETALL, q); 164 blk_queue_required_elevator_features(q, ELEVATOR_F_ZBD_SEQ_WRITE); 165 blk_queue_chunk_sectors(q, dev->zone_size_sects); 166 nullb->disk->nr_zones = bdev_nr_zones(nullb->disk->part0); 167 blk_queue_max_zone_append_sectors(q, dev->zone_size_sects); 168 disk_set_max_open_zones(nullb->disk, dev->zone_max_open); 169 disk_set_max_active_zones(nullb->disk, dev->zone_max_active); 170 171 if (queue_is_mq(q)) 172 return blk_revalidate_disk_zones(nullb->disk, NULL); 173 174 return 0; 175 } 176 177 void null_free_zoned_dev(struct nullb_device *dev) 178 { 179 kvfree(dev->zones); 180 dev->zones = NULL; 181 } 182 183 int null_report_zones(struct gendisk *disk, sector_t sector, 184 unsigned int nr_zones, report_zones_cb cb, void *data) 185 { 186 struct nullb *nullb = disk->private_data; 187 struct nullb_device *dev = nullb->dev; 188 unsigned int first_zone, i; 189 struct nullb_zone *zone; 190 struct blk_zone blkz; 191 int error; 192 193 first_zone = null_zone_no(dev, sector); 194 if (first_zone >= dev->nr_zones) 195 return 0; 196 197 nr_zones = min(nr_zones, dev->nr_zones - first_zone); 198 trace_nullb_report_zones(nullb, nr_zones); 199 200 memset(&blkz, 0, sizeof(struct blk_zone)); 201 zone = &dev->zones[first_zone]; 202 for (i = 0; i < nr_zones; i++, zone++) { 203 /* 204 * Stacked DM target drivers will remap the zone information by 205 * modifying the zone information passed to the report callback. 206 * So use a local copy to avoid corruption of the device zone 207 * array. 208 */ 209 null_lock_zone(dev, zone); 210 blkz.start = zone->start; 211 blkz.len = zone->len; 212 blkz.wp = zone->wp; 213 blkz.type = zone->type; 214 blkz.cond = zone->cond; 215 blkz.capacity = zone->capacity; 216 null_unlock_zone(dev, zone); 217 218 error = cb(&blkz, i, data); 219 if (error) 220 return error; 221 } 222 223 return nr_zones; 224 } 225 226 /* 227 * This is called in the case of memory backing from null_process_cmd() 228 * with the target zone already locked. 229 */ 230 size_t null_zone_valid_read_len(struct nullb *nullb, 231 sector_t sector, unsigned int len) 232 { 233 struct nullb_device *dev = nullb->dev; 234 struct nullb_zone *zone = &dev->zones[null_zone_no(dev, sector)]; 235 unsigned int nr_sectors = len >> SECTOR_SHIFT; 236 237 /* Read must be below the write pointer position */ 238 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL || 239 sector + nr_sectors <= zone->wp) 240 return len; 241 242 if (sector > zone->wp) 243 return 0; 244 245 return (zone->wp - sector) << SECTOR_SHIFT; 246 } 247 248 static blk_status_t __null_close_zone(struct nullb_device *dev, 249 struct nullb_zone *zone) 250 { 251 switch (zone->cond) { 252 case BLK_ZONE_COND_CLOSED: 253 /* close operation on closed is not an error */ 254 return BLK_STS_OK; 255 case BLK_ZONE_COND_IMP_OPEN: 256 dev->nr_zones_imp_open--; 257 break; 258 case BLK_ZONE_COND_EXP_OPEN: 259 dev->nr_zones_exp_open--; 260 break; 261 case BLK_ZONE_COND_EMPTY: 262 case BLK_ZONE_COND_FULL: 263 default: 264 return BLK_STS_IOERR; 265 } 266 267 if (zone->wp == zone->start) { 268 zone->cond = BLK_ZONE_COND_EMPTY; 269 } else { 270 zone->cond = BLK_ZONE_COND_CLOSED; 271 dev->nr_zones_closed++; 272 } 273 274 return BLK_STS_OK; 275 } 276 277 static void null_close_imp_open_zone(struct nullb_device *dev) 278 { 279 struct nullb_zone *zone; 280 unsigned int zno, i; 281 282 zno = dev->imp_close_zone_no; 283 if (zno >= dev->nr_zones) 284 zno = dev->zone_nr_conv; 285 286 for (i = dev->zone_nr_conv; i < dev->nr_zones; i++) { 287 zone = &dev->zones[zno]; 288 zno++; 289 if (zno >= dev->nr_zones) 290 zno = dev->zone_nr_conv; 291 292 if (zone->cond == BLK_ZONE_COND_IMP_OPEN) { 293 __null_close_zone(dev, zone); 294 dev->imp_close_zone_no = zno; 295 return; 296 } 297 } 298 } 299 300 static blk_status_t null_check_active(struct nullb_device *dev) 301 { 302 if (!dev->zone_max_active) 303 return BLK_STS_OK; 304 305 if (dev->nr_zones_exp_open + dev->nr_zones_imp_open + 306 dev->nr_zones_closed < dev->zone_max_active) 307 return BLK_STS_OK; 308 309 return BLK_STS_ZONE_ACTIVE_RESOURCE; 310 } 311 312 static blk_status_t null_check_open(struct nullb_device *dev) 313 { 314 if (!dev->zone_max_open) 315 return BLK_STS_OK; 316 317 if (dev->nr_zones_exp_open + dev->nr_zones_imp_open < dev->zone_max_open) 318 return BLK_STS_OK; 319 320 if (dev->nr_zones_imp_open) { 321 if (null_check_active(dev) == BLK_STS_OK) { 322 null_close_imp_open_zone(dev); 323 return BLK_STS_OK; 324 } 325 } 326 327 return BLK_STS_ZONE_OPEN_RESOURCE; 328 } 329 330 /* 331 * This function matches the manage open zone resources function in the ZBC standard, 332 * with the addition of max active zones support (added in the ZNS standard). 333 * 334 * The function determines if a zone can transition to implicit open or explicit open, 335 * while maintaining the max open zone (and max active zone) limit(s). It may close an 336 * implicit open zone in order to make additional zone resources available. 337 * 338 * ZBC states that an implicit open zone shall be closed only if there is not 339 * room within the open limit. However, with the addition of an active limit, 340 * it is not certain that closing an implicit open zone will allow a new zone 341 * to be opened, since we might already be at the active limit capacity. 342 */ 343 static blk_status_t null_check_zone_resources(struct nullb_device *dev, 344 struct nullb_zone *zone) 345 { 346 blk_status_t ret; 347 348 switch (zone->cond) { 349 case BLK_ZONE_COND_EMPTY: 350 ret = null_check_active(dev); 351 if (ret != BLK_STS_OK) 352 return ret; 353 fallthrough; 354 case BLK_ZONE_COND_CLOSED: 355 return null_check_open(dev); 356 default: 357 /* Should never be called for other states */ 358 WARN_ON(1); 359 return BLK_STS_IOERR; 360 } 361 } 362 363 static blk_status_t null_zone_write(struct nullb_cmd *cmd, sector_t sector, 364 unsigned int nr_sectors, bool append) 365 { 366 struct nullb_device *dev = cmd->nq->dev; 367 unsigned int zno = null_zone_no(dev, sector); 368 struct nullb_zone *zone = &dev->zones[zno]; 369 blk_status_t ret; 370 371 trace_nullb_zone_op(cmd, zno, zone->cond); 372 373 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL) { 374 if (append) 375 return BLK_STS_IOERR; 376 return null_process_cmd(cmd, REQ_OP_WRITE, sector, nr_sectors); 377 } 378 379 null_lock_zone(dev, zone); 380 381 if (zone->cond == BLK_ZONE_COND_FULL || 382 zone->cond == BLK_ZONE_COND_READONLY || 383 zone->cond == BLK_ZONE_COND_OFFLINE) { 384 /* Cannot write to the zone */ 385 ret = BLK_STS_IOERR; 386 goto unlock; 387 } 388 389 /* 390 * Regular writes must be at the write pointer position. 391 * Zone append writes are automatically issued at the write 392 * pointer and the position returned using the request or BIO 393 * sector. 394 */ 395 if (append) { 396 sector = zone->wp; 397 if (dev->queue_mode == NULL_Q_MQ) 398 cmd->rq->__sector = sector; 399 else 400 cmd->bio->bi_iter.bi_sector = sector; 401 } else if (sector != zone->wp) { 402 ret = BLK_STS_IOERR; 403 goto unlock; 404 } 405 406 if (zone->wp + nr_sectors > zone->start + zone->capacity) { 407 ret = BLK_STS_IOERR; 408 goto unlock; 409 } 410 411 if (zone->cond == BLK_ZONE_COND_CLOSED || 412 zone->cond == BLK_ZONE_COND_EMPTY) { 413 null_lock_zone_res(dev); 414 415 ret = null_check_zone_resources(dev, zone); 416 if (ret != BLK_STS_OK) { 417 null_unlock_zone_res(dev); 418 goto unlock; 419 } 420 if (zone->cond == BLK_ZONE_COND_CLOSED) { 421 dev->nr_zones_closed--; 422 dev->nr_zones_imp_open++; 423 } else if (zone->cond == BLK_ZONE_COND_EMPTY) { 424 dev->nr_zones_imp_open++; 425 } 426 427 if (zone->cond != BLK_ZONE_COND_EXP_OPEN) 428 zone->cond = BLK_ZONE_COND_IMP_OPEN; 429 430 null_unlock_zone_res(dev); 431 } 432 433 ret = null_process_cmd(cmd, REQ_OP_WRITE, sector, nr_sectors); 434 if (ret != BLK_STS_OK) 435 goto unlock; 436 437 zone->wp += nr_sectors; 438 if (zone->wp == zone->start + zone->capacity) { 439 null_lock_zone_res(dev); 440 if (zone->cond == BLK_ZONE_COND_EXP_OPEN) 441 dev->nr_zones_exp_open--; 442 else if (zone->cond == BLK_ZONE_COND_IMP_OPEN) 443 dev->nr_zones_imp_open--; 444 zone->cond = BLK_ZONE_COND_FULL; 445 null_unlock_zone_res(dev); 446 } 447 448 ret = BLK_STS_OK; 449 450 unlock: 451 null_unlock_zone(dev, zone); 452 453 return ret; 454 } 455 456 static blk_status_t null_open_zone(struct nullb_device *dev, 457 struct nullb_zone *zone) 458 { 459 blk_status_t ret = BLK_STS_OK; 460 461 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL) 462 return BLK_STS_IOERR; 463 464 null_lock_zone_res(dev); 465 466 switch (zone->cond) { 467 case BLK_ZONE_COND_EXP_OPEN: 468 /* open operation on exp open is not an error */ 469 goto unlock; 470 case BLK_ZONE_COND_EMPTY: 471 ret = null_check_zone_resources(dev, zone); 472 if (ret != BLK_STS_OK) 473 goto unlock; 474 break; 475 case BLK_ZONE_COND_IMP_OPEN: 476 dev->nr_zones_imp_open--; 477 break; 478 case BLK_ZONE_COND_CLOSED: 479 ret = null_check_zone_resources(dev, zone); 480 if (ret != BLK_STS_OK) 481 goto unlock; 482 dev->nr_zones_closed--; 483 break; 484 case BLK_ZONE_COND_FULL: 485 default: 486 ret = BLK_STS_IOERR; 487 goto unlock; 488 } 489 490 zone->cond = BLK_ZONE_COND_EXP_OPEN; 491 dev->nr_zones_exp_open++; 492 493 unlock: 494 null_unlock_zone_res(dev); 495 496 return ret; 497 } 498 499 static blk_status_t null_close_zone(struct nullb_device *dev, 500 struct nullb_zone *zone) 501 { 502 blk_status_t ret; 503 504 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL) 505 return BLK_STS_IOERR; 506 507 null_lock_zone_res(dev); 508 ret = __null_close_zone(dev, zone); 509 null_unlock_zone_res(dev); 510 511 return ret; 512 } 513 514 static blk_status_t null_finish_zone(struct nullb_device *dev, 515 struct nullb_zone *zone) 516 { 517 blk_status_t ret = BLK_STS_OK; 518 519 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL) 520 return BLK_STS_IOERR; 521 522 null_lock_zone_res(dev); 523 524 switch (zone->cond) { 525 case BLK_ZONE_COND_FULL: 526 /* finish operation on full is not an error */ 527 goto unlock; 528 case BLK_ZONE_COND_EMPTY: 529 ret = null_check_zone_resources(dev, zone); 530 if (ret != BLK_STS_OK) 531 goto unlock; 532 break; 533 case BLK_ZONE_COND_IMP_OPEN: 534 dev->nr_zones_imp_open--; 535 break; 536 case BLK_ZONE_COND_EXP_OPEN: 537 dev->nr_zones_exp_open--; 538 break; 539 case BLK_ZONE_COND_CLOSED: 540 ret = null_check_zone_resources(dev, zone); 541 if (ret != BLK_STS_OK) 542 goto unlock; 543 dev->nr_zones_closed--; 544 break; 545 default: 546 ret = BLK_STS_IOERR; 547 goto unlock; 548 } 549 550 zone->cond = BLK_ZONE_COND_FULL; 551 zone->wp = zone->start + zone->len; 552 553 unlock: 554 null_unlock_zone_res(dev); 555 556 return ret; 557 } 558 559 static blk_status_t null_reset_zone(struct nullb_device *dev, 560 struct nullb_zone *zone) 561 { 562 if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL) 563 return BLK_STS_IOERR; 564 565 null_lock_zone_res(dev); 566 567 switch (zone->cond) { 568 case BLK_ZONE_COND_EMPTY: 569 /* reset operation on empty is not an error */ 570 null_unlock_zone_res(dev); 571 return BLK_STS_OK; 572 case BLK_ZONE_COND_IMP_OPEN: 573 dev->nr_zones_imp_open--; 574 break; 575 case BLK_ZONE_COND_EXP_OPEN: 576 dev->nr_zones_exp_open--; 577 break; 578 case BLK_ZONE_COND_CLOSED: 579 dev->nr_zones_closed--; 580 break; 581 case BLK_ZONE_COND_FULL: 582 break; 583 default: 584 null_unlock_zone_res(dev); 585 return BLK_STS_IOERR; 586 } 587 588 zone->cond = BLK_ZONE_COND_EMPTY; 589 zone->wp = zone->start; 590 591 null_unlock_zone_res(dev); 592 593 if (dev->memory_backed) 594 return null_handle_discard(dev, zone->start, zone->len); 595 596 return BLK_STS_OK; 597 } 598 599 static blk_status_t null_zone_mgmt(struct nullb_cmd *cmd, enum req_op op, 600 sector_t sector) 601 { 602 struct nullb_device *dev = cmd->nq->dev; 603 unsigned int zone_no; 604 struct nullb_zone *zone; 605 blk_status_t ret; 606 size_t i; 607 608 if (op == REQ_OP_ZONE_RESET_ALL) { 609 for (i = dev->zone_nr_conv; i < dev->nr_zones; i++) { 610 zone = &dev->zones[i]; 611 null_lock_zone(dev, zone); 612 if (zone->cond != BLK_ZONE_COND_EMPTY && 613 zone->cond != BLK_ZONE_COND_READONLY && 614 zone->cond != BLK_ZONE_COND_OFFLINE) { 615 null_reset_zone(dev, zone); 616 trace_nullb_zone_op(cmd, i, zone->cond); 617 } 618 null_unlock_zone(dev, zone); 619 } 620 return BLK_STS_OK; 621 } 622 623 zone_no = null_zone_no(dev, sector); 624 zone = &dev->zones[zone_no]; 625 626 null_lock_zone(dev, zone); 627 628 if (zone->cond == BLK_ZONE_COND_READONLY || 629 zone->cond == BLK_ZONE_COND_OFFLINE) { 630 ret = BLK_STS_IOERR; 631 goto unlock; 632 } 633 634 switch (op) { 635 case REQ_OP_ZONE_RESET: 636 ret = null_reset_zone(dev, zone); 637 break; 638 case REQ_OP_ZONE_OPEN: 639 ret = null_open_zone(dev, zone); 640 break; 641 case REQ_OP_ZONE_CLOSE: 642 ret = null_close_zone(dev, zone); 643 break; 644 case REQ_OP_ZONE_FINISH: 645 ret = null_finish_zone(dev, zone); 646 break; 647 default: 648 ret = BLK_STS_NOTSUPP; 649 break; 650 } 651 652 if (ret == BLK_STS_OK) 653 trace_nullb_zone_op(cmd, zone_no, zone->cond); 654 655 unlock: 656 null_unlock_zone(dev, zone); 657 658 return ret; 659 } 660 661 blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd, enum req_op op, 662 sector_t sector, sector_t nr_sectors) 663 { 664 struct nullb_device *dev; 665 struct nullb_zone *zone; 666 blk_status_t sts; 667 668 switch (op) { 669 case REQ_OP_WRITE: 670 return null_zone_write(cmd, sector, nr_sectors, false); 671 case REQ_OP_ZONE_APPEND: 672 return null_zone_write(cmd, sector, nr_sectors, true); 673 case REQ_OP_ZONE_RESET: 674 case REQ_OP_ZONE_RESET_ALL: 675 case REQ_OP_ZONE_OPEN: 676 case REQ_OP_ZONE_CLOSE: 677 case REQ_OP_ZONE_FINISH: 678 return null_zone_mgmt(cmd, op, sector); 679 default: 680 dev = cmd->nq->dev; 681 zone = &dev->zones[null_zone_no(dev, sector)]; 682 if (zone->cond == BLK_ZONE_COND_OFFLINE) 683 return BLK_STS_IOERR; 684 685 null_lock_zone(dev, zone); 686 sts = null_process_cmd(cmd, op, sector, nr_sectors); 687 null_unlock_zone(dev, zone); 688 return sts; 689 } 690 } 691 692 /* 693 * Set a zone in the read-only or offline condition. 694 */ 695 static void null_set_zone_cond(struct nullb_device *dev, 696 struct nullb_zone *zone, enum blk_zone_cond cond) 697 { 698 if (WARN_ON_ONCE(cond != BLK_ZONE_COND_READONLY && 699 cond != BLK_ZONE_COND_OFFLINE)) 700 return; 701 702 null_lock_zone(dev, zone); 703 704 /* 705 * If the read-only condition is requested again to zones already in 706 * read-only condition, restore back normal empty condition. Do the same 707 * if the offline condition is requested for offline zones. Otherwise, 708 * set the specified zone condition to the zones. Finish the zones 709 * beforehand to free up zone resources. 710 */ 711 if (zone->cond == cond) { 712 zone->cond = BLK_ZONE_COND_EMPTY; 713 zone->wp = zone->start; 714 if (dev->memory_backed) 715 null_handle_discard(dev, zone->start, zone->len); 716 } else { 717 if (zone->cond != BLK_ZONE_COND_READONLY && 718 zone->cond != BLK_ZONE_COND_OFFLINE) 719 null_finish_zone(dev, zone); 720 zone->cond = cond; 721 zone->wp = (sector_t)-1; 722 } 723 724 null_unlock_zone(dev, zone); 725 } 726 727 /* 728 * Identify a zone from the sector written to configfs file. Then set zone 729 * condition to the zone. 730 */ 731 ssize_t zone_cond_store(struct nullb_device *dev, const char *page, 732 size_t count, enum blk_zone_cond cond) 733 { 734 unsigned long long sector; 735 unsigned int zone_no; 736 int ret; 737 738 if (!dev->zoned) { 739 pr_err("null_blk device is not zoned\n"); 740 return -EINVAL; 741 } 742 743 if (!dev->zones) { 744 pr_err("null_blk device is not yet powered\n"); 745 return -EINVAL; 746 } 747 748 ret = kstrtoull(page, 0, §or); 749 if (ret < 0) 750 return ret; 751 752 zone_no = null_zone_no(dev, sector); 753 if (zone_no >= dev->nr_zones) { 754 pr_err("Sector out of range\n"); 755 return -EINVAL; 756 } 757 758 if (dev->zones[zone_no].type == BLK_ZONE_TYPE_CONVENTIONAL) { 759 pr_err("Can not change condition of conventional zones\n"); 760 return -EINVAL; 761 } 762 763 null_set_zone_cond(dev, &dev->zones[zone_no], cond); 764 765 return count; 766 } 767