1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Functions related to sysfs handling 4 */ 5 #include <linux/kernel.h> 6 #include <linux/slab.h> 7 #include <linux/module.h> 8 #include <linux/bio.h> 9 #include <linux/blkdev.h> 10 #include <linux/backing-dev.h> 11 #include <linux/blktrace_api.h> 12 #include <linux/debugfs.h> 13 14 #include "blk.h" 15 #include "blk-mq.h" 16 #include "blk-mq-debugfs.h" 17 #include "blk-mq-sched.h" 18 #include "blk-rq-qos.h" 19 #include "blk-wbt.h" 20 #include "blk-cgroup.h" 21 #include "blk-throttle.h" 22 23 struct queue_sysfs_entry { 24 struct attribute attr; 25 ssize_t (*show)(struct request_queue *, char *); 26 ssize_t (*store)(struct request_queue *, const char *, size_t); 27 }; 28 29 static ssize_t 30 queue_var_show(unsigned long var, char *page) 31 { 32 return sprintf(page, "%lu\n", var); 33 } 34 35 static ssize_t 36 queue_var_store(unsigned long *var, const char *page, size_t count) 37 { 38 int err; 39 unsigned long v; 40 41 err = kstrtoul(page, 10, &v); 42 if (err || v > UINT_MAX) 43 return -EINVAL; 44 45 *var = v; 46 47 return count; 48 } 49 50 static ssize_t queue_requests_show(struct request_queue *q, char *page) 51 { 52 return queue_var_show(q->nr_requests, page); 53 } 54 55 static ssize_t 56 queue_requests_store(struct request_queue *q, const char *page, size_t count) 57 { 58 unsigned long nr; 59 int ret, err; 60 61 if (!queue_is_mq(q)) 62 return -EINVAL; 63 64 ret = queue_var_store(&nr, page, count); 65 if (ret < 0) 66 return ret; 67 68 if (nr < BLKDEV_MIN_RQ) 69 nr = BLKDEV_MIN_RQ; 70 71 err = blk_mq_update_nr_requests(q, nr); 72 if (err) 73 return err; 74 75 return ret; 76 } 77 78 static ssize_t queue_ra_show(struct request_queue *q, char *page) 79 { 80 unsigned long ra_kb; 81 82 if (!q->disk) 83 return -EINVAL; 84 ra_kb = q->disk->bdi->ra_pages << (PAGE_SHIFT - 10); 85 return queue_var_show(ra_kb, page); 86 } 87 88 static ssize_t 89 queue_ra_store(struct request_queue *q, const char *page, size_t count) 90 { 91 unsigned long ra_kb; 92 ssize_t ret; 93 94 if (!q->disk) 95 return -EINVAL; 96 ret = queue_var_store(&ra_kb, page, count); 97 if (ret < 0) 98 return ret; 99 q->disk->bdi->ra_pages = ra_kb >> (PAGE_SHIFT - 10); 100 return ret; 101 } 102 103 static ssize_t queue_max_sectors_show(struct request_queue *q, char *page) 104 { 105 int max_sectors_kb = queue_max_sectors(q) >> 1; 106 107 return queue_var_show(max_sectors_kb, page); 108 } 109 110 static ssize_t queue_max_segments_show(struct request_queue *q, char *page) 111 { 112 return queue_var_show(queue_max_segments(q), page); 113 } 114 115 static ssize_t queue_max_discard_segments_show(struct request_queue *q, 116 char *page) 117 { 118 return queue_var_show(queue_max_discard_segments(q), page); 119 } 120 121 static ssize_t queue_max_integrity_segments_show(struct request_queue *q, char *page) 122 { 123 return queue_var_show(q->limits.max_integrity_segments, page); 124 } 125 126 static ssize_t queue_max_segment_size_show(struct request_queue *q, char *page) 127 { 128 return queue_var_show(queue_max_segment_size(q), page); 129 } 130 131 static ssize_t queue_logical_block_size_show(struct request_queue *q, char *page) 132 { 133 return queue_var_show(queue_logical_block_size(q), page); 134 } 135 136 static ssize_t queue_physical_block_size_show(struct request_queue *q, char *page) 137 { 138 return queue_var_show(queue_physical_block_size(q), page); 139 } 140 141 static ssize_t queue_chunk_sectors_show(struct request_queue *q, char *page) 142 { 143 return queue_var_show(q->limits.chunk_sectors, page); 144 } 145 146 static ssize_t queue_io_min_show(struct request_queue *q, char *page) 147 { 148 return queue_var_show(queue_io_min(q), page); 149 } 150 151 static ssize_t queue_io_opt_show(struct request_queue *q, char *page) 152 { 153 return queue_var_show(queue_io_opt(q), page); 154 } 155 156 static ssize_t queue_discard_granularity_show(struct request_queue *q, char *page) 157 { 158 return queue_var_show(q->limits.discard_granularity, page); 159 } 160 161 static ssize_t queue_discard_max_hw_show(struct request_queue *q, char *page) 162 { 163 164 return sprintf(page, "%llu\n", 165 (unsigned long long)q->limits.max_hw_discard_sectors << 9); 166 } 167 168 static ssize_t queue_discard_max_show(struct request_queue *q, char *page) 169 { 170 return sprintf(page, "%llu\n", 171 (unsigned long long)q->limits.max_discard_sectors << 9); 172 } 173 174 static ssize_t queue_discard_max_store(struct request_queue *q, 175 const char *page, size_t count) 176 { 177 unsigned long max_discard_bytes; 178 struct queue_limits lim; 179 ssize_t ret; 180 int err; 181 182 ret = queue_var_store(&max_discard_bytes, page, count); 183 if (ret < 0) 184 return ret; 185 186 if (max_discard_bytes & (q->limits.discard_granularity - 1)) 187 return -EINVAL; 188 189 if ((max_discard_bytes >> SECTOR_SHIFT) > UINT_MAX) 190 return -EINVAL; 191 192 blk_mq_freeze_queue(q); 193 lim = queue_limits_start_update(q); 194 lim.max_user_discard_sectors = max_discard_bytes >> SECTOR_SHIFT; 195 err = queue_limits_commit_update(q, &lim); 196 blk_mq_unfreeze_queue(q); 197 198 if (err) 199 return err; 200 return ret; 201 } 202 203 static ssize_t queue_discard_zeroes_data_show(struct request_queue *q, char *page) 204 { 205 return queue_var_show(0, page); 206 } 207 208 static ssize_t queue_write_same_max_show(struct request_queue *q, char *page) 209 { 210 return queue_var_show(0, page); 211 } 212 213 static ssize_t queue_write_zeroes_max_show(struct request_queue *q, char *page) 214 { 215 return sprintf(page, "%llu\n", 216 (unsigned long long)q->limits.max_write_zeroes_sectors << 9); 217 } 218 219 static ssize_t queue_zone_write_granularity_show(struct request_queue *q, 220 char *page) 221 { 222 return queue_var_show(queue_zone_write_granularity(q), page); 223 } 224 225 static ssize_t queue_zone_append_max_show(struct request_queue *q, char *page) 226 { 227 unsigned long long max_sectors = q->limits.max_zone_append_sectors; 228 229 return sprintf(page, "%llu\n", max_sectors << SECTOR_SHIFT); 230 } 231 232 static ssize_t 233 queue_max_sectors_store(struct request_queue *q, const char *page, size_t count) 234 { 235 unsigned long max_sectors_kb; 236 struct queue_limits lim; 237 ssize_t ret; 238 int err; 239 240 ret = queue_var_store(&max_sectors_kb, page, count); 241 if (ret < 0) 242 return ret; 243 244 blk_mq_freeze_queue(q); 245 lim = queue_limits_start_update(q); 246 lim.max_user_sectors = max_sectors_kb << 1; 247 err = queue_limits_commit_update(q, &lim); 248 blk_mq_unfreeze_queue(q); 249 if (err) 250 return err; 251 return ret; 252 } 253 254 static ssize_t queue_max_hw_sectors_show(struct request_queue *q, char *page) 255 { 256 int max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1; 257 258 return queue_var_show(max_hw_sectors_kb, page); 259 } 260 261 static ssize_t queue_virt_boundary_mask_show(struct request_queue *q, char *page) 262 { 263 return queue_var_show(q->limits.virt_boundary_mask, page); 264 } 265 266 static ssize_t queue_dma_alignment_show(struct request_queue *q, char *page) 267 { 268 return queue_var_show(queue_dma_alignment(q), page); 269 } 270 271 #define QUEUE_SYSFS_BIT_FNS(name, flag, neg) \ 272 static ssize_t \ 273 queue_##name##_show(struct request_queue *q, char *page) \ 274 { \ 275 int bit; \ 276 bit = test_bit(QUEUE_FLAG_##flag, &q->queue_flags); \ 277 return queue_var_show(neg ? !bit : bit, page); \ 278 } \ 279 static ssize_t \ 280 queue_##name##_store(struct request_queue *q, const char *page, size_t count) \ 281 { \ 282 unsigned long val; \ 283 ssize_t ret; \ 284 ret = queue_var_store(&val, page, count); \ 285 if (ret < 0) \ 286 return ret; \ 287 if (neg) \ 288 val = !val; \ 289 \ 290 if (val) \ 291 blk_queue_flag_set(QUEUE_FLAG_##flag, q); \ 292 else \ 293 blk_queue_flag_clear(QUEUE_FLAG_##flag, q); \ 294 return ret; \ 295 } 296 297 QUEUE_SYSFS_BIT_FNS(nonrot, NONROT, 1); 298 QUEUE_SYSFS_BIT_FNS(random, ADD_RANDOM, 0); 299 QUEUE_SYSFS_BIT_FNS(iostats, IO_STAT, 0); 300 QUEUE_SYSFS_BIT_FNS(stable_writes, STABLE_WRITES, 0); 301 #undef QUEUE_SYSFS_BIT_FNS 302 303 static ssize_t queue_zoned_show(struct request_queue *q, char *page) 304 { 305 if (blk_queue_is_zoned(q)) 306 return sprintf(page, "host-managed\n"); 307 return sprintf(page, "none\n"); 308 } 309 310 static ssize_t queue_nr_zones_show(struct request_queue *q, char *page) 311 { 312 return queue_var_show(disk_nr_zones(q->disk), page); 313 } 314 315 static ssize_t queue_max_open_zones_show(struct request_queue *q, char *page) 316 { 317 return queue_var_show(bdev_max_open_zones(q->disk->part0), page); 318 } 319 320 static ssize_t queue_max_active_zones_show(struct request_queue *q, char *page) 321 { 322 return queue_var_show(bdev_max_active_zones(q->disk->part0), page); 323 } 324 325 static ssize_t queue_nomerges_show(struct request_queue *q, char *page) 326 { 327 return queue_var_show((blk_queue_nomerges(q) << 1) | 328 blk_queue_noxmerges(q), page); 329 } 330 331 static ssize_t queue_nomerges_store(struct request_queue *q, const char *page, 332 size_t count) 333 { 334 unsigned long nm; 335 ssize_t ret = queue_var_store(&nm, page, count); 336 337 if (ret < 0) 338 return ret; 339 340 blk_queue_flag_clear(QUEUE_FLAG_NOMERGES, q); 341 blk_queue_flag_clear(QUEUE_FLAG_NOXMERGES, q); 342 if (nm == 2) 343 blk_queue_flag_set(QUEUE_FLAG_NOMERGES, q); 344 else if (nm) 345 blk_queue_flag_set(QUEUE_FLAG_NOXMERGES, q); 346 347 return ret; 348 } 349 350 static ssize_t queue_rq_affinity_show(struct request_queue *q, char *page) 351 { 352 bool set = test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags); 353 bool force = test_bit(QUEUE_FLAG_SAME_FORCE, &q->queue_flags); 354 355 return queue_var_show(set << force, page); 356 } 357 358 static ssize_t 359 queue_rq_affinity_store(struct request_queue *q, const char *page, size_t count) 360 { 361 ssize_t ret = -EINVAL; 362 #ifdef CONFIG_SMP 363 unsigned long val; 364 365 ret = queue_var_store(&val, page, count); 366 if (ret < 0) 367 return ret; 368 369 if (val == 2) { 370 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q); 371 blk_queue_flag_set(QUEUE_FLAG_SAME_FORCE, q); 372 } else if (val == 1) { 373 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q); 374 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q); 375 } else if (val == 0) { 376 blk_queue_flag_clear(QUEUE_FLAG_SAME_COMP, q); 377 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q); 378 } 379 #endif 380 return ret; 381 } 382 383 static ssize_t queue_poll_delay_show(struct request_queue *q, char *page) 384 { 385 return sprintf(page, "%d\n", -1); 386 } 387 388 static ssize_t queue_poll_delay_store(struct request_queue *q, const char *page, 389 size_t count) 390 { 391 return count; 392 } 393 394 static ssize_t queue_poll_show(struct request_queue *q, char *page) 395 { 396 return queue_var_show(test_bit(QUEUE_FLAG_POLL, &q->queue_flags), page); 397 } 398 399 static ssize_t queue_poll_store(struct request_queue *q, const char *page, 400 size_t count) 401 { 402 if (!test_bit(QUEUE_FLAG_POLL, &q->queue_flags)) 403 return -EINVAL; 404 pr_info_ratelimited("writes to the poll attribute are ignored.\n"); 405 pr_info_ratelimited("please use driver specific parameters instead.\n"); 406 return count; 407 } 408 409 static ssize_t queue_io_timeout_show(struct request_queue *q, char *page) 410 { 411 return sprintf(page, "%u\n", jiffies_to_msecs(q->rq_timeout)); 412 } 413 414 static ssize_t queue_io_timeout_store(struct request_queue *q, const char *page, 415 size_t count) 416 { 417 unsigned int val; 418 int err; 419 420 err = kstrtou32(page, 10, &val); 421 if (err || val == 0) 422 return -EINVAL; 423 424 blk_queue_rq_timeout(q, msecs_to_jiffies(val)); 425 426 return count; 427 } 428 429 static ssize_t queue_wc_show(struct request_queue *q, char *page) 430 { 431 if (test_bit(QUEUE_FLAG_WC, &q->queue_flags)) 432 return sprintf(page, "write back\n"); 433 434 return sprintf(page, "write through\n"); 435 } 436 437 static ssize_t queue_wc_store(struct request_queue *q, const char *page, 438 size_t count) 439 { 440 if (!strncmp(page, "write back", 10)) { 441 if (!test_bit(QUEUE_FLAG_HW_WC, &q->queue_flags)) 442 return -EINVAL; 443 blk_queue_flag_set(QUEUE_FLAG_WC, q); 444 } else if (!strncmp(page, "write through", 13) || 445 !strncmp(page, "none", 4)) { 446 blk_queue_flag_clear(QUEUE_FLAG_WC, q); 447 } else { 448 return -EINVAL; 449 } 450 451 return count; 452 } 453 454 static ssize_t queue_fua_show(struct request_queue *q, char *page) 455 { 456 return sprintf(page, "%u\n", test_bit(QUEUE_FLAG_FUA, &q->queue_flags)); 457 } 458 459 static ssize_t queue_dax_show(struct request_queue *q, char *page) 460 { 461 return queue_var_show(blk_queue_dax(q), page); 462 } 463 464 #define QUEUE_RO_ENTRY(_prefix, _name) \ 465 static struct queue_sysfs_entry _prefix##_entry = { \ 466 .attr = { .name = _name, .mode = 0444 }, \ 467 .show = _prefix##_show, \ 468 }; 469 470 #define QUEUE_RW_ENTRY(_prefix, _name) \ 471 static struct queue_sysfs_entry _prefix##_entry = { \ 472 .attr = { .name = _name, .mode = 0644 }, \ 473 .show = _prefix##_show, \ 474 .store = _prefix##_store, \ 475 }; 476 477 QUEUE_RW_ENTRY(queue_requests, "nr_requests"); 478 QUEUE_RW_ENTRY(queue_ra, "read_ahead_kb"); 479 QUEUE_RW_ENTRY(queue_max_sectors, "max_sectors_kb"); 480 QUEUE_RO_ENTRY(queue_max_hw_sectors, "max_hw_sectors_kb"); 481 QUEUE_RO_ENTRY(queue_max_segments, "max_segments"); 482 QUEUE_RO_ENTRY(queue_max_integrity_segments, "max_integrity_segments"); 483 QUEUE_RO_ENTRY(queue_max_segment_size, "max_segment_size"); 484 QUEUE_RW_ENTRY(elv_iosched, "scheduler"); 485 486 QUEUE_RO_ENTRY(queue_logical_block_size, "logical_block_size"); 487 QUEUE_RO_ENTRY(queue_physical_block_size, "physical_block_size"); 488 QUEUE_RO_ENTRY(queue_chunk_sectors, "chunk_sectors"); 489 QUEUE_RO_ENTRY(queue_io_min, "minimum_io_size"); 490 QUEUE_RO_ENTRY(queue_io_opt, "optimal_io_size"); 491 492 QUEUE_RO_ENTRY(queue_max_discard_segments, "max_discard_segments"); 493 QUEUE_RO_ENTRY(queue_discard_granularity, "discard_granularity"); 494 QUEUE_RO_ENTRY(queue_discard_max_hw, "discard_max_hw_bytes"); 495 QUEUE_RW_ENTRY(queue_discard_max, "discard_max_bytes"); 496 QUEUE_RO_ENTRY(queue_discard_zeroes_data, "discard_zeroes_data"); 497 498 QUEUE_RO_ENTRY(queue_write_same_max, "write_same_max_bytes"); 499 QUEUE_RO_ENTRY(queue_write_zeroes_max, "write_zeroes_max_bytes"); 500 QUEUE_RO_ENTRY(queue_zone_append_max, "zone_append_max_bytes"); 501 QUEUE_RO_ENTRY(queue_zone_write_granularity, "zone_write_granularity"); 502 503 QUEUE_RO_ENTRY(queue_zoned, "zoned"); 504 QUEUE_RO_ENTRY(queue_nr_zones, "nr_zones"); 505 QUEUE_RO_ENTRY(queue_max_open_zones, "max_open_zones"); 506 QUEUE_RO_ENTRY(queue_max_active_zones, "max_active_zones"); 507 508 QUEUE_RW_ENTRY(queue_nomerges, "nomerges"); 509 QUEUE_RW_ENTRY(queue_rq_affinity, "rq_affinity"); 510 QUEUE_RW_ENTRY(queue_poll, "io_poll"); 511 QUEUE_RW_ENTRY(queue_poll_delay, "io_poll_delay"); 512 QUEUE_RW_ENTRY(queue_wc, "write_cache"); 513 QUEUE_RO_ENTRY(queue_fua, "fua"); 514 QUEUE_RO_ENTRY(queue_dax, "dax"); 515 QUEUE_RW_ENTRY(queue_io_timeout, "io_timeout"); 516 QUEUE_RO_ENTRY(queue_virt_boundary_mask, "virt_boundary_mask"); 517 QUEUE_RO_ENTRY(queue_dma_alignment, "dma_alignment"); 518 519 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW 520 QUEUE_RW_ENTRY(blk_throtl_sample_time, "throttle_sample_time"); 521 #endif 522 523 /* legacy alias for logical_block_size: */ 524 static struct queue_sysfs_entry queue_hw_sector_size_entry = { 525 .attr = {.name = "hw_sector_size", .mode = 0444 }, 526 .show = queue_logical_block_size_show, 527 }; 528 529 QUEUE_RW_ENTRY(queue_nonrot, "rotational"); 530 QUEUE_RW_ENTRY(queue_iostats, "iostats"); 531 QUEUE_RW_ENTRY(queue_random, "add_random"); 532 QUEUE_RW_ENTRY(queue_stable_writes, "stable_writes"); 533 534 #ifdef CONFIG_BLK_WBT 535 static ssize_t queue_var_store64(s64 *var, const char *page) 536 { 537 int err; 538 s64 v; 539 540 err = kstrtos64(page, 10, &v); 541 if (err < 0) 542 return err; 543 544 *var = v; 545 return 0; 546 } 547 548 static ssize_t queue_wb_lat_show(struct request_queue *q, char *page) 549 { 550 if (!wbt_rq_qos(q)) 551 return -EINVAL; 552 553 if (wbt_disabled(q)) 554 return sprintf(page, "0\n"); 555 556 return sprintf(page, "%llu\n", div_u64(wbt_get_min_lat(q), 1000)); 557 } 558 559 static ssize_t queue_wb_lat_store(struct request_queue *q, const char *page, 560 size_t count) 561 { 562 struct rq_qos *rqos; 563 ssize_t ret; 564 s64 val; 565 566 ret = queue_var_store64(&val, page); 567 if (ret < 0) 568 return ret; 569 if (val < -1) 570 return -EINVAL; 571 572 rqos = wbt_rq_qos(q); 573 if (!rqos) { 574 ret = wbt_init(q->disk); 575 if (ret) 576 return ret; 577 } 578 579 if (val == -1) 580 val = wbt_default_latency_nsec(q); 581 else if (val >= 0) 582 val *= 1000ULL; 583 584 if (wbt_get_min_lat(q) == val) 585 return count; 586 587 /* 588 * Ensure that the queue is idled, in case the latency update 589 * ends up either enabling or disabling wbt completely. We can't 590 * have IO inflight if that happens. 591 */ 592 blk_mq_freeze_queue(q); 593 blk_mq_quiesce_queue(q); 594 595 wbt_set_min_lat(q, val); 596 597 blk_mq_unquiesce_queue(q); 598 blk_mq_unfreeze_queue(q); 599 600 return count; 601 } 602 603 QUEUE_RW_ENTRY(queue_wb_lat, "wbt_lat_usec"); 604 #endif 605 606 /* Common attributes for bio-based and request-based queues. */ 607 static struct attribute *queue_attrs[] = { 608 &queue_ra_entry.attr, 609 &queue_max_hw_sectors_entry.attr, 610 &queue_max_sectors_entry.attr, 611 &queue_max_segments_entry.attr, 612 &queue_max_discard_segments_entry.attr, 613 &queue_max_integrity_segments_entry.attr, 614 &queue_max_segment_size_entry.attr, 615 &queue_hw_sector_size_entry.attr, 616 &queue_logical_block_size_entry.attr, 617 &queue_physical_block_size_entry.attr, 618 &queue_chunk_sectors_entry.attr, 619 &queue_io_min_entry.attr, 620 &queue_io_opt_entry.attr, 621 &queue_discard_granularity_entry.attr, 622 &queue_discard_max_entry.attr, 623 &queue_discard_max_hw_entry.attr, 624 &queue_discard_zeroes_data_entry.attr, 625 &queue_write_same_max_entry.attr, 626 &queue_write_zeroes_max_entry.attr, 627 &queue_zone_append_max_entry.attr, 628 &queue_zone_write_granularity_entry.attr, 629 &queue_nonrot_entry.attr, 630 &queue_zoned_entry.attr, 631 &queue_nr_zones_entry.attr, 632 &queue_max_open_zones_entry.attr, 633 &queue_max_active_zones_entry.attr, 634 &queue_nomerges_entry.attr, 635 &queue_iostats_entry.attr, 636 &queue_stable_writes_entry.attr, 637 &queue_random_entry.attr, 638 &queue_poll_entry.attr, 639 &queue_wc_entry.attr, 640 &queue_fua_entry.attr, 641 &queue_dax_entry.attr, 642 &queue_poll_delay_entry.attr, 643 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW 644 &blk_throtl_sample_time_entry.attr, 645 #endif 646 &queue_virt_boundary_mask_entry.attr, 647 &queue_dma_alignment_entry.attr, 648 NULL, 649 }; 650 651 /* Request-based queue attributes that are not relevant for bio-based queues. */ 652 static struct attribute *blk_mq_queue_attrs[] = { 653 &queue_requests_entry.attr, 654 &elv_iosched_entry.attr, 655 &queue_rq_affinity_entry.attr, 656 &queue_io_timeout_entry.attr, 657 #ifdef CONFIG_BLK_WBT 658 &queue_wb_lat_entry.attr, 659 #endif 660 NULL, 661 }; 662 663 static umode_t queue_attr_visible(struct kobject *kobj, struct attribute *attr, 664 int n) 665 { 666 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 667 struct request_queue *q = disk->queue; 668 669 if ((attr == &queue_max_open_zones_entry.attr || 670 attr == &queue_max_active_zones_entry.attr) && 671 !blk_queue_is_zoned(q)) 672 return 0; 673 674 return attr->mode; 675 } 676 677 static umode_t blk_mq_queue_attr_visible(struct kobject *kobj, 678 struct attribute *attr, int n) 679 { 680 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 681 struct request_queue *q = disk->queue; 682 683 if (!queue_is_mq(q)) 684 return 0; 685 686 if (attr == &queue_io_timeout_entry.attr && !q->mq_ops->timeout) 687 return 0; 688 689 return attr->mode; 690 } 691 692 static struct attribute_group queue_attr_group = { 693 .attrs = queue_attrs, 694 .is_visible = queue_attr_visible, 695 }; 696 697 static struct attribute_group blk_mq_queue_attr_group = { 698 .attrs = blk_mq_queue_attrs, 699 .is_visible = blk_mq_queue_attr_visible, 700 }; 701 702 #define to_queue(atr) container_of((atr), struct queue_sysfs_entry, attr) 703 704 static ssize_t 705 queue_attr_show(struct kobject *kobj, struct attribute *attr, char *page) 706 { 707 struct queue_sysfs_entry *entry = to_queue(attr); 708 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 709 struct request_queue *q = disk->queue; 710 ssize_t res; 711 712 if (!entry->show) 713 return -EIO; 714 mutex_lock(&q->sysfs_lock); 715 res = entry->show(q, page); 716 mutex_unlock(&q->sysfs_lock); 717 return res; 718 } 719 720 static ssize_t 721 queue_attr_store(struct kobject *kobj, struct attribute *attr, 722 const char *page, size_t length) 723 { 724 struct queue_sysfs_entry *entry = to_queue(attr); 725 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 726 struct request_queue *q = disk->queue; 727 ssize_t res; 728 729 if (!entry->store) 730 return -EIO; 731 732 mutex_lock(&q->sysfs_lock); 733 res = entry->store(q, page, length); 734 mutex_unlock(&q->sysfs_lock); 735 return res; 736 } 737 738 static const struct sysfs_ops queue_sysfs_ops = { 739 .show = queue_attr_show, 740 .store = queue_attr_store, 741 }; 742 743 static const struct attribute_group *blk_queue_attr_groups[] = { 744 &queue_attr_group, 745 &blk_mq_queue_attr_group, 746 NULL 747 }; 748 749 static void blk_queue_release(struct kobject *kobj) 750 { 751 /* nothing to do here, all data is associated with the parent gendisk */ 752 } 753 754 static const struct kobj_type blk_queue_ktype = { 755 .default_groups = blk_queue_attr_groups, 756 .sysfs_ops = &queue_sysfs_ops, 757 .release = blk_queue_release, 758 }; 759 760 static void blk_debugfs_remove(struct gendisk *disk) 761 { 762 struct request_queue *q = disk->queue; 763 764 mutex_lock(&q->debugfs_mutex); 765 blk_trace_shutdown(q); 766 debugfs_remove_recursive(q->debugfs_dir); 767 q->debugfs_dir = NULL; 768 q->sched_debugfs_dir = NULL; 769 q->rqos_debugfs_dir = NULL; 770 mutex_unlock(&q->debugfs_mutex); 771 } 772 773 /** 774 * blk_register_queue - register a block layer queue with sysfs 775 * @disk: Disk of which the request queue should be registered with sysfs. 776 */ 777 int blk_register_queue(struct gendisk *disk) 778 { 779 struct request_queue *q = disk->queue; 780 int ret; 781 782 mutex_lock(&q->sysfs_dir_lock); 783 kobject_init(&disk->queue_kobj, &blk_queue_ktype); 784 ret = kobject_add(&disk->queue_kobj, &disk_to_dev(disk)->kobj, "queue"); 785 if (ret < 0) 786 goto out_put_queue_kobj; 787 788 if (queue_is_mq(q)) { 789 ret = blk_mq_sysfs_register(disk); 790 if (ret) 791 goto out_put_queue_kobj; 792 } 793 mutex_lock(&q->sysfs_lock); 794 795 mutex_lock(&q->debugfs_mutex); 796 q->debugfs_dir = debugfs_create_dir(disk->disk_name, blk_debugfs_root); 797 if (queue_is_mq(q)) 798 blk_mq_debugfs_register(q); 799 mutex_unlock(&q->debugfs_mutex); 800 801 ret = disk_register_independent_access_ranges(disk); 802 if (ret) 803 goto out_debugfs_remove; 804 805 if (q->elevator) { 806 ret = elv_register_queue(q, false); 807 if (ret) 808 goto out_unregister_ia_ranges; 809 } 810 811 ret = blk_crypto_sysfs_register(disk); 812 if (ret) 813 goto out_elv_unregister; 814 815 blk_queue_flag_set(QUEUE_FLAG_REGISTERED, q); 816 wbt_enable_default(disk); 817 blk_throtl_register(disk); 818 819 /* Now everything is ready and send out KOBJ_ADD uevent */ 820 kobject_uevent(&disk->queue_kobj, KOBJ_ADD); 821 if (q->elevator) 822 kobject_uevent(&q->elevator->kobj, KOBJ_ADD); 823 mutex_unlock(&q->sysfs_lock); 824 mutex_unlock(&q->sysfs_dir_lock); 825 826 /* 827 * SCSI probing may synchronously create and destroy a lot of 828 * request_queues for non-existent devices. Shutting down a fully 829 * functional queue takes measureable wallclock time as RCU grace 830 * periods are involved. To avoid excessive latency in these 831 * cases, a request_queue starts out in a degraded mode which is 832 * faster to shut down and is made fully functional here as 833 * request_queues for non-existent devices never get registered. 834 */ 835 if (!blk_queue_init_done(q)) { 836 blk_queue_flag_set(QUEUE_FLAG_INIT_DONE, q); 837 percpu_ref_switch_to_percpu(&q->q_usage_counter); 838 } 839 840 return ret; 841 842 out_elv_unregister: 843 elv_unregister_queue(q); 844 out_unregister_ia_ranges: 845 disk_unregister_independent_access_ranges(disk); 846 out_debugfs_remove: 847 blk_debugfs_remove(disk); 848 mutex_unlock(&q->sysfs_lock); 849 out_put_queue_kobj: 850 kobject_put(&disk->queue_kobj); 851 mutex_unlock(&q->sysfs_dir_lock); 852 return ret; 853 } 854 855 /** 856 * blk_unregister_queue - counterpart of blk_register_queue() 857 * @disk: Disk of which the request queue should be unregistered from sysfs. 858 * 859 * Note: the caller is responsible for guaranteeing that this function is called 860 * after blk_register_queue() has finished. 861 */ 862 void blk_unregister_queue(struct gendisk *disk) 863 { 864 struct request_queue *q = disk->queue; 865 866 if (WARN_ON(!q)) 867 return; 868 869 /* Return early if disk->queue was never registered. */ 870 if (!blk_queue_registered(q)) 871 return; 872 873 /* 874 * Since sysfs_remove_dir() prevents adding new directory entries 875 * before removal of existing entries starts, protect against 876 * concurrent elv_iosched_store() calls. 877 */ 878 mutex_lock(&q->sysfs_lock); 879 blk_queue_flag_clear(QUEUE_FLAG_REGISTERED, q); 880 mutex_unlock(&q->sysfs_lock); 881 882 mutex_lock(&q->sysfs_dir_lock); 883 /* 884 * Remove the sysfs attributes before unregistering the queue data 885 * structures that can be modified through sysfs. 886 */ 887 if (queue_is_mq(q)) 888 blk_mq_sysfs_unregister(disk); 889 blk_crypto_sysfs_unregister(disk); 890 891 mutex_lock(&q->sysfs_lock); 892 elv_unregister_queue(q); 893 disk_unregister_independent_access_ranges(disk); 894 mutex_unlock(&q->sysfs_lock); 895 896 /* Now that we've deleted all child objects, we can delete the queue. */ 897 kobject_uevent(&disk->queue_kobj, KOBJ_REMOVE); 898 kobject_del(&disk->queue_kobj); 899 mutex_unlock(&q->sysfs_dir_lock); 900 901 blk_debugfs_remove(disk); 902 } 903