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; 178 ssize_t ret = queue_var_store(&max_discard, page, count); 179 180 if (ret < 0) 181 return ret; 182 183 if (max_discard & (q->limits.discard_granularity - 1)) 184 return -EINVAL; 185 186 max_discard >>= 9; 187 if (max_discard > UINT_MAX) 188 return -EINVAL; 189 190 if (max_discard > q->limits.max_hw_discard_sectors) 191 max_discard = q->limits.max_hw_discard_sectors; 192 193 q->limits.max_discard_sectors = max_discard; 194 return ret; 195 } 196 197 static ssize_t queue_discard_zeroes_data_show(struct request_queue *q, char *page) 198 { 199 return queue_var_show(0, page); 200 } 201 202 static ssize_t queue_write_same_max_show(struct request_queue *q, char *page) 203 { 204 return queue_var_show(0, page); 205 } 206 207 static ssize_t queue_write_zeroes_max_show(struct request_queue *q, char *page) 208 { 209 return sprintf(page, "%llu\n", 210 (unsigned long long)q->limits.max_write_zeroes_sectors << 9); 211 } 212 213 static ssize_t queue_zone_write_granularity_show(struct request_queue *q, 214 char *page) 215 { 216 return queue_var_show(queue_zone_write_granularity(q), page); 217 } 218 219 static ssize_t queue_zone_append_max_show(struct request_queue *q, char *page) 220 { 221 unsigned long long max_sectors = q->limits.max_zone_append_sectors; 222 223 return sprintf(page, "%llu\n", max_sectors << SECTOR_SHIFT); 224 } 225 226 static ssize_t 227 queue_max_sectors_store(struct request_queue *q, const char *page, size_t count) 228 { 229 unsigned long var; 230 unsigned int max_sectors_kb, 231 max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1, 232 page_kb = 1 << (PAGE_SHIFT - 10); 233 ssize_t ret = queue_var_store(&var, page, count); 234 235 if (ret < 0) 236 return ret; 237 238 max_sectors_kb = (unsigned int)var; 239 max_hw_sectors_kb = min_not_zero(max_hw_sectors_kb, 240 q->limits.max_dev_sectors >> 1); 241 if (max_sectors_kb == 0) { 242 q->limits.max_user_sectors = 0; 243 max_sectors_kb = min(max_hw_sectors_kb, 244 BLK_DEF_MAX_SECTORS >> 1); 245 } else { 246 if (max_sectors_kb > max_hw_sectors_kb || 247 max_sectors_kb < page_kb) 248 return -EINVAL; 249 q->limits.max_user_sectors = max_sectors_kb << 1; 250 } 251 252 spin_lock_irq(&q->queue_lock); 253 q->limits.max_sectors = max_sectors_kb << 1; 254 if (q->disk) 255 q->disk->bdi->io_pages = max_sectors_kb >> (PAGE_SHIFT - 10); 256 spin_unlock_irq(&q->queue_lock); 257 258 return ret; 259 } 260 261 static ssize_t queue_max_hw_sectors_show(struct request_queue *q, char *page) 262 { 263 int max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1; 264 265 return queue_var_show(max_hw_sectors_kb, page); 266 } 267 268 static ssize_t queue_virt_boundary_mask_show(struct request_queue *q, char *page) 269 { 270 return queue_var_show(q->limits.virt_boundary_mask, page); 271 } 272 273 static ssize_t queue_dma_alignment_show(struct request_queue *q, char *page) 274 { 275 return queue_var_show(queue_dma_alignment(q), page); 276 } 277 278 #define QUEUE_SYSFS_BIT_FNS(name, flag, neg) \ 279 static ssize_t \ 280 queue_##name##_show(struct request_queue *q, char *page) \ 281 { \ 282 int bit; \ 283 bit = test_bit(QUEUE_FLAG_##flag, &q->queue_flags); \ 284 return queue_var_show(neg ? !bit : bit, page); \ 285 } \ 286 static ssize_t \ 287 queue_##name##_store(struct request_queue *q, const char *page, size_t count) \ 288 { \ 289 unsigned long val; \ 290 ssize_t ret; \ 291 ret = queue_var_store(&val, page, count); \ 292 if (ret < 0) \ 293 return ret; \ 294 if (neg) \ 295 val = !val; \ 296 \ 297 if (val) \ 298 blk_queue_flag_set(QUEUE_FLAG_##flag, q); \ 299 else \ 300 blk_queue_flag_clear(QUEUE_FLAG_##flag, q); \ 301 return ret; \ 302 } 303 304 QUEUE_SYSFS_BIT_FNS(nonrot, NONROT, 1); 305 QUEUE_SYSFS_BIT_FNS(random, ADD_RANDOM, 0); 306 QUEUE_SYSFS_BIT_FNS(iostats, IO_STAT, 0); 307 QUEUE_SYSFS_BIT_FNS(stable_writes, STABLE_WRITES, 0); 308 #undef QUEUE_SYSFS_BIT_FNS 309 310 static ssize_t queue_zoned_show(struct request_queue *q, char *page) 311 { 312 switch (blk_queue_zoned_model(q)) { 313 case BLK_ZONED_HA: 314 return sprintf(page, "host-aware\n"); 315 case BLK_ZONED_HM: 316 return sprintf(page, "host-managed\n"); 317 default: 318 return sprintf(page, "none\n"); 319 } 320 } 321 322 static ssize_t queue_nr_zones_show(struct request_queue *q, char *page) 323 { 324 return queue_var_show(disk_nr_zones(q->disk), page); 325 } 326 327 static ssize_t queue_max_open_zones_show(struct request_queue *q, char *page) 328 { 329 return queue_var_show(bdev_max_open_zones(q->disk->part0), page); 330 } 331 332 static ssize_t queue_max_active_zones_show(struct request_queue *q, char *page) 333 { 334 return queue_var_show(bdev_max_active_zones(q->disk->part0), page); 335 } 336 337 static ssize_t queue_nomerges_show(struct request_queue *q, char *page) 338 { 339 return queue_var_show((blk_queue_nomerges(q) << 1) | 340 blk_queue_noxmerges(q), page); 341 } 342 343 static ssize_t queue_nomerges_store(struct request_queue *q, const char *page, 344 size_t count) 345 { 346 unsigned long nm; 347 ssize_t ret = queue_var_store(&nm, page, count); 348 349 if (ret < 0) 350 return ret; 351 352 blk_queue_flag_clear(QUEUE_FLAG_NOMERGES, q); 353 blk_queue_flag_clear(QUEUE_FLAG_NOXMERGES, q); 354 if (nm == 2) 355 blk_queue_flag_set(QUEUE_FLAG_NOMERGES, q); 356 else if (nm) 357 blk_queue_flag_set(QUEUE_FLAG_NOXMERGES, q); 358 359 return ret; 360 } 361 362 static ssize_t queue_rq_affinity_show(struct request_queue *q, char *page) 363 { 364 bool set = test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags); 365 bool force = test_bit(QUEUE_FLAG_SAME_FORCE, &q->queue_flags); 366 367 return queue_var_show(set << force, page); 368 } 369 370 static ssize_t 371 queue_rq_affinity_store(struct request_queue *q, const char *page, size_t count) 372 { 373 ssize_t ret = -EINVAL; 374 #ifdef CONFIG_SMP 375 unsigned long val; 376 377 ret = queue_var_store(&val, page, count); 378 if (ret < 0) 379 return ret; 380 381 if (val == 2) { 382 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q); 383 blk_queue_flag_set(QUEUE_FLAG_SAME_FORCE, q); 384 } else if (val == 1) { 385 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q); 386 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q); 387 } else if (val == 0) { 388 blk_queue_flag_clear(QUEUE_FLAG_SAME_COMP, q); 389 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q); 390 } 391 #endif 392 return ret; 393 } 394 395 static ssize_t queue_poll_delay_show(struct request_queue *q, char *page) 396 { 397 return sprintf(page, "%d\n", -1); 398 } 399 400 static ssize_t queue_poll_delay_store(struct request_queue *q, const char *page, 401 size_t count) 402 { 403 return count; 404 } 405 406 static ssize_t queue_poll_show(struct request_queue *q, char *page) 407 { 408 return queue_var_show(test_bit(QUEUE_FLAG_POLL, &q->queue_flags), page); 409 } 410 411 static ssize_t queue_poll_store(struct request_queue *q, const char *page, 412 size_t count) 413 { 414 if (!test_bit(QUEUE_FLAG_POLL, &q->queue_flags)) 415 return -EINVAL; 416 pr_info_ratelimited("writes to the poll attribute are ignored.\n"); 417 pr_info_ratelimited("please use driver specific parameters instead.\n"); 418 return count; 419 } 420 421 static ssize_t queue_io_timeout_show(struct request_queue *q, char *page) 422 { 423 return sprintf(page, "%u\n", jiffies_to_msecs(q->rq_timeout)); 424 } 425 426 static ssize_t queue_io_timeout_store(struct request_queue *q, const char *page, 427 size_t count) 428 { 429 unsigned int val; 430 int err; 431 432 err = kstrtou32(page, 10, &val); 433 if (err || val == 0) 434 return -EINVAL; 435 436 blk_queue_rq_timeout(q, msecs_to_jiffies(val)); 437 438 return count; 439 } 440 441 static ssize_t queue_wc_show(struct request_queue *q, char *page) 442 { 443 if (test_bit(QUEUE_FLAG_WC, &q->queue_flags)) 444 return sprintf(page, "write back\n"); 445 446 return sprintf(page, "write through\n"); 447 } 448 449 static ssize_t queue_wc_store(struct request_queue *q, const char *page, 450 size_t count) 451 { 452 int set = -1; 453 454 if (!strncmp(page, "write back", 10)) 455 set = 1; 456 else if (!strncmp(page, "write through", 13) || 457 !strncmp(page, "none", 4)) 458 set = 0; 459 460 if (set == -1) 461 return -EINVAL; 462 463 if (set) 464 blk_queue_flag_set(QUEUE_FLAG_WC, q); 465 else 466 blk_queue_flag_clear(QUEUE_FLAG_WC, q); 467 468 return count; 469 } 470 471 static ssize_t queue_fua_show(struct request_queue *q, char *page) 472 { 473 return sprintf(page, "%u\n", test_bit(QUEUE_FLAG_FUA, &q->queue_flags)); 474 } 475 476 static ssize_t queue_dax_show(struct request_queue *q, char *page) 477 { 478 return queue_var_show(blk_queue_dax(q), page); 479 } 480 481 #define QUEUE_RO_ENTRY(_prefix, _name) \ 482 static struct queue_sysfs_entry _prefix##_entry = { \ 483 .attr = { .name = _name, .mode = 0444 }, \ 484 .show = _prefix##_show, \ 485 }; 486 487 #define QUEUE_RW_ENTRY(_prefix, _name) \ 488 static struct queue_sysfs_entry _prefix##_entry = { \ 489 .attr = { .name = _name, .mode = 0644 }, \ 490 .show = _prefix##_show, \ 491 .store = _prefix##_store, \ 492 }; 493 494 QUEUE_RW_ENTRY(queue_requests, "nr_requests"); 495 QUEUE_RW_ENTRY(queue_ra, "read_ahead_kb"); 496 QUEUE_RW_ENTRY(queue_max_sectors, "max_sectors_kb"); 497 QUEUE_RO_ENTRY(queue_max_hw_sectors, "max_hw_sectors_kb"); 498 QUEUE_RO_ENTRY(queue_max_segments, "max_segments"); 499 QUEUE_RO_ENTRY(queue_max_integrity_segments, "max_integrity_segments"); 500 QUEUE_RO_ENTRY(queue_max_segment_size, "max_segment_size"); 501 QUEUE_RW_ENTRY(elv_iosched, "scheduler"); 502 503 QUEUE_RO_ENTRY(queue_logical_block_size, "logical_block_size"); 504 QUEUE_RO_ENTRY(queue_physical_block_size, "physical_block_size"); 505 QUEUE_RO_ENTRY(queue_chunk_sectors, "chunk_sectors"); 506 QUEUE_RO_ENTRY(queue_io_min, "minimum_io_size"); 507 QUEUE_RO_ENTRY(queue_io_opt, "optimal_io_size"); 508 509 QUEUE_RO_ENTRY(queue_max_discard_segments, "max_discard_segments"); 510 QUEUE_RO_ENTRY(queue_discard_granularity, "discard_granularity"); 511 QUEUE_RO_ENTRY(queue_discard_max_hw, "discard_max_hw_bytes"); 512 QUEUE_RW_ENTRY(queue_discard_max, "discard_max_bytes"); 513 QUEUE_RO_ENTRY(queue_discard_zeroes_data, "discard_zeroes_data"); 514 515 QUEUE_RO_ENTRY(queue_write_same_max, "write_same_max_bytes"); 516 QUEUE_RO_ENTRY(queue_write_zeroes_max, "write_zeroes_max_bytes"); 517 QUEUE_RO_ENTRY(queue_zone_append_max, "zone_append_max_bytes"); 518 QUEUE_RO_ENTRY(queue_zone_write_granularity, "zone_write_granularity"); 519 520 QUEUE_RO_ENTRY(queue_zoned, "zoned"); 521 QUEUE_RO_ENTRY(queue_nr_zones, "nr_zones"); 522 QUEUE_RO_ENTRY(queue_max_open_zones, "max_open_zones"); 523 QUEUE_RO_ENTRY(queue_max_active_zones, "max_active_zones"); 524 525 QUEUE_RW_ENTRY(queue_nomerges, "nomerges"); 526 QUEUE_RW_ENTRY(queue_rq_affinity, "rq_affinity"); 527 QUEUE_RW_ENTRY(queue_poll, "io_poll"); 528 QUEUE_RW_ENTRY(queue_poll_delay, "io_poll_delay"); 529 QUEUE_RW_ENTRY(queue_wc, "write_cache"); 530 QUEUE_RO_ENTRY(queue_fua, "fua"); 531 QUEUE_RO_ENTRY(queue_dax, "dax"); 532 QUEUE_RW_ENTRY(queue_io_timeout, "io_timeout"); 533 QUEUE_RO_ENTRY(queue_virt_boundary_mask, "virt_boundary_mask"); 534 QUEUE_RO_ENTRY(queue_dma_alignment, "dma_alignment"); 535 536 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW 537 QUEUE_RW_ENTRY(blk_throtl_sample_time, "throttle_sample_time"); 538 #endif 539 540 /* legacy alias for logical_block_size: */ 541 static struct queue_sysfs_entry queue_hw_sector_size_entry = { 542 .attr = {.name = "hw_sector_size", .mode = 0444 }, 543 .show = queue_logical_block_size_show, 544 }; 545 546 QUEUE_RW_ENTRY(queue_nonrot, "rotational"); 547 QUEUE_RW_ENTRY(queue_iostats, "iostats"); 548 QUEUE_RW_ENTRY(queue_random, "add_random"); 549 QUEUE_RW_ENTRY(queue_stable_writes, "stable_writes"); 550 551 #ifdef CONFIG_BLK_WBT 552 static ssize_t queue_var_store64(s64 *var, const char *page) 553 { 554 int err; 555 s64 v; 556 557 err = kstrtos64(page, 10, &v); 558 if (err < 0) 559 return err; 560 561 *var = v; 562 return 0; 563 } 564 565 static ssize_t queue_wb_lat_show(struct request_queue *q, char *page) 566 { 567 if (!wbt_rq_qos(q)) 568 return -EINVAL; 569 570 if (wbt_disabled(q)) 571 return sprintf(page, "0\n"); 572 573 return sprintf(page, "%llu\n", div_u64(wbt_get_min_lat(q), 1000)); 574 } 575 576 static ssize_t queue_wb_lat_store(struct request_queue *q, const char *page, 577 size_t count) 578 { 579 struct rq_qos *rqos; 580 ssize_t ret; 581 s64 val; 582 583 ret = queue_var_store64(&val, page); 584 if (ret < 0) 585 return ret; 586 if (val < -1) 587 return -EINVAL; 588 589 rqos = wbt_rq_qos(q); 590 if (!rqos) { 591 ret = wbt_init(q->disk); 592 if (ret) 593 return ret; 594 } 595 596 if (val == -1) 597 val = wbt_default_latency_nsec(q); 598 else if (val >= 0) 599 val *= 1000ULL; 600 601 if (wbt_get_min_lat(q) == val) 602 return count; 603 604 /* 605 * Ensure that the queue is idled, in case the latency update 606 * ends up either enabling or disabling wbt completely. We can't 607 * have IO inflight if that happens. 608 */ 609 blk_mq_freeze_queue(q); 610 blk_mq_quiesce_queue(q); 611 612 wbt_set_min_lat(q, val); 613 614 blk_mq_unquiesce_queue(q); 615 blk_mq_unfreeze_queue(q); 616 617 return count; 618 } 619 620 QUEUE_RW_ENTRY(queue_wb_lat, "wbt_lat_usec"); 621 #endif 622 623 static struct attribute *queue_attrs[] = { 624 &queue_ra_entry.attr, 625 &queue_max_hw_sectors_entry.attr, 626 &queue_max_sectors_entry.attr, 627 &queue_max_segments_entry.attr, 628 &queue_max_discard_segments_entry.attr, 629 &queue_max_integrity_segments_entry.attr, 630 &queue_max_segment_size_entry.attr, 631 &queue_hw_sector_size_entry.attr, 632 &queue_logical_block_size_entry.attr, 633 &queue_physical_block_size_entry.attr, 634 &queue_chunk_sectors_entry.attr, 635 &queue_io_min_entry.attr, 636 &queue_io_opt_entry.attr, 637 &queue_discard_granularity_entry.attr, 638 &queue_discard_max_entry.attr, 639 &queue_discard_max_hw_entry.attr, 640 &queue_discard_zeroes_data_entry.attr, 641 &queue_write_same_max_entry.attr, 642 &queue_write_zeroes_max_entry.attr, 643 &queue_zone_append_max_entry.attr, 644 &queue_zone_write_granularity_entry.attr, 645 &queue_nonrot_entry.attr, 646 &queue_zoned_entry.attr, 647 &queue_nr_zones_entry.attr, 648 &queue_max_open_zones_entry.attr, 649 &queue_max_active_zones_entry.attr, 650 &queue_nomerges_entry.attr, 651 &queue_iostats_entry.attr, 652 &queue_stable_writes_entry.attr, 653 &queue_random_entry.attr, 654 &queue_poll_entry.attr, 655 &queue_wc_entry.attr, 656 &queue_fua_entry.attr, 657 &queue_dax_entry.attr, 658 &queue_poll_delay_entry.attr, 659 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW 660 &blk_throtl_sample_time_entry.attr, 661 #endif 662 &queue_virt_boundary_mask_entry.attr, 663 &queue_dma_alignment_entry.attr, 664 NULL, 665 }; 666 667 static struct attribute *blk_mq_queue_attrs[] = { 668 &queue_requests_entry.attr, 669 &elv_iosched_entry.attr, 670 &queue_rq_affinity_entry.attr, 671 &queue_io_timeout_entry.attr, 672 #ifdef CONFIG_BLK_WBT 673 &queue_wb_lat_entry.attr, 674 #endif 675 NULL, 676 }; 677 678 static umode_t queue_attr_visible(struct kobject *kobj, struct attribute *attr, 679 int n) 680 { 681 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 682 struct request_queue *q = disk->queue; 683 684 if ((attr == &queue_max_open_zones_entry.attr || 685 attr == &queue_max_active_zones_entry.attr) && 686 !blk_queue_is_zoned(q)) 687 return 0; 688 689 return attr->mode; 690 } 691 692 static umode_t blk_mq_queue_attr_visible(struct kobject *kobj, 693 struct attribute *attr, int n) 694 { 695 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 696 struct request_queue *q = disk->queue; 697 698 if (!queue_is_mq(q)) 699 return 0; 700 701 if (attr == &queue_io_timeout_entry.attr && !q->mq_ops->timeout) 702 return 0; 703 704 return attr->mode; 705 } 706 707 static struct attribute_group queue_attr_group = { 708 .attrs = queue_attrs, 709 .is_visible = queue_attr_visible, 710 }; 711 712 static struct attribute_group blk_mq_queue_attr_group = { 713 .attrs = blk_mq_queue_attrs, 714 .is_visible = blk_mq_queue_attr_visible, 715 }; 716 717 #define to_queue(atr) container_of((atr), struct queue_sysfs_entry, attr) 718 719 static ssize_t 720 queue_attr_show(struct kobject *kobj, struct attribute *attr, char *page) 721 { 722 struct queue_sysfs_entry *entry = to_queue(attr); 723 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 724 struct request_queue *q = disk->queue; 725 ssize_t res; 726 727 if (!entry->show) 728 return -EIO; 729 mutex_lock(&q->sysfs_lock); 730 res = entry->show(q, page); 731 mutex_unlock(&q->sysfs_lock); 732 return res; 733 } 734 735 static ssize_t 736 queue_attr_store(struct kobject *kobj, struct attribute *attr, 737 const char *page, size_t length) 738 { 739 struct queue_sysfs_entry *entry = to_queue(attr); 740 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 741 struct request_queue *q = disk->queue; 742 ssize_t res; 743 744 if (!entry->store) 745 return -EIO; 746 747 mutex_lock(&q->sysfs_lock); 748 res = entry->store(q, page, length); 749 mutex_unlock(&q->sysfs_lock); 750 return res; 751 } 752 753 static const struct sysfs_ops queue_sysfs_ops = { 754 .show = queue_attr_show, 755 .store = queue_attr_store, 756 }; 757 758 static const struct attribute_group *blk_queue_attr_groups[] = { 759 &queue_attr_group, 760 &blk_mq_queue_attr_group, 761 NULL 762 }; 763 764 static void blk_queue_release(struct kobject *kobj) 765 { 766 /* nothing to do here, all data is associated with the parent gendisk */ 767 } 768 769 static const struct kobj_type blk_queue_ktype = { 770 .default_groups = blk_queue_attr_groups, 771 .sysfs_ops = &queue_sysfs_ops, 772 .release = blk_queue_release, 773 }; 774 775 static void blk_debugfs_remove(struct gendisk *disk) 776 { 777 struct request_queue *q = disk->queue; 778 779 mutex_lock(&q->debugfs_mutex); 780 blk_trace_shutdown(q); 781 debugfs_remove_recursive(q->debugfs_dir); 782 q->debugfs_dir = NULL; 783 q->sched_debugfs_dir = NULL; 784 q->rqos_debugfs_dir = NULL; 785 mutex_unlock(&q->debugfs_mutex); 786 } 787 788 /** 789 * blk_register_queue - register a block layer queue with sysfs 790 * @disk: Disk of which the request queue should be registered with sysfs. 791 */ 792 int blk_register_queue(struct gendisk *disk) 793 { 794 struct request_queue *q = disk->queue; 795 int ret; 796 797 mutex_lock(&q->sysfs_dir_lock); 798 kobject_init(&disk->queue_kobj, &blk_queue_ktype); 799 ret = kobject_add(&disk->queue_kobj, &disk_to_dev(disk)->kobj, "queue"); 800 if (ret < 0) 801 goto out_put_queue_kobj; 802 803 if (queue_is_mq(q)) { 804 ret = blk_mq_sysfs_register(disk); 805 if (ret) 806 goto out_put_queue_kobj; 807 } 808 mutex_lock(&q->sysfs_lock); 809 810 mutex_lock(&q->debugfs_mutex); 811 q->debugfs_dir = debugfs_create_dir(disk->disk_name, blk_debugfs_root); 812 if (queue_is_mq(q)) 813 blk_mq_debugfs_register(q); 814 mutex_unlock(&q->debugfs_mutex); 815 816 ret = disk_register_independent_access_ranges(disk); 817 if (ret) 818 goto out_debugfs_remove; 819 820 if (q->elevator) { 821 ret = elv_register_queue(q, false); 822 if (ret) 823 goto out_unregister_ia_ranges; 824 } 825 826 ret = blk_crypto_sysfs_register(disk); 827 if (ret) 828 goto out_elv_unregister; 829 830 blk_queue_flag_set(QUEUE_FLAG_REGISTERED, q); 831 wbt_enable_default(disk); 832 blk_throtl_register(disk); 833 834 /* Now everything is ready and send out KOBJ_ADD uevent */ 835 kobject_uevent(&disk->queue_kobj, KOBJ_ADD); 836 if (q->elevator) 837 kobject_uevent(&q->elevator->kobj, KOBJ_ADD); 838 mutex_unlock(&q->sysfs_lock); 839 mutex_unlock(&q->sysfs_dir_lock); 840 841 /* 842 * SCSI probing may synchronously create and destroy a lot of 843 * request_queues for non-existent devices. Shutting down a fully 844 * functional queue takes measureable wallclock time as RCU grace 845 * periods are involved. To avoid excessive latency in these 846 * cases, a request_queue starts out in a degraded mode which is 847 * faster to shut down and is made fully functional here as 848 * request_queues for non-existent devices never get registered. 849 */ 850 if (!blk_queue_init_done(q)) { 851 blk_queue_flag_set(QUEUE_FLAG_INIT_DONE, q); 852 percpu_ref_switch_to_percpu(&q->q_usage_counter); 853 } 854 855 return ret; 856 857 out_elv_unregister: 858 elv_unregister_queue(q); 859 out_unregister_ia_ranges: 860 disk_unregister_independent_access_ranges(disk); 861 out_debugfs_remove: 862 blk_debugfs_remove(disk); 863 mutex_unlock(&q->sysfs_lock); 864 out_put_queue_kobj: 865 kobject_put(&disk->queue_kobj); 866 mutex_unlock(&q->sysfs_dir_lock); 867 return ret; 868 } 869 870 /** 871 * blk_unregister_queue - counterpart of blk_register_queue() 872 * @disk: Disk of which the request queue should be unregistered from sysfs. 873 * 874 * Note: the caller is responsible for guaranteeing that this function is called 875 * after blk_register_queue() has finished. 876 */ 877 void blk_unregister_queue(struct gendisk *disk) 878 { 879 struct request_queue *q = disk->queue; 880 881 if (WARN_ON(!q)) 882 return; 883 884 /* Return early if disk->queue was never registered. */ 885 if (!blk_queue_registered(q)) 886 return; 887 888 /* 889 * Since sysfs_remove_dir() prevents adding new directory entries 890 * before removal of existing entries starts, protect against 891 * concurrent elv_iosched_store() calls. 892 */ 893 mutex_lock(&q->sysfs_lock); 894 blk_queue_flag_clear(QUEUE_FLAG_REGISTERED, q); 895 mutex_unlock(&q->sysfs_lock); 896 897 mutex_lock(&q->sysfs_dir_lock); 898 /* 899 * Remove the sysfs attributes before unregistering the queue data 900 * structures that can be modified through sysfs. 901 */ 902 if (queue_is_mq(q)) 903 blk_mq_sysfs_unregister(disk); 904 blk_crypto_sysfs_unregister(disk); 905 906 mutex_lock(&q->sysfs_lock); 907 elv_unregister_queue(q); 908 disk_unregister_independent_access_ranges(disk); 909 mutex_unlock(&q->sysfs_lock); 910 911 /* Now that we've deleted all child objects, we can delete the queue. */ 912 kobject_uevent(&disk->queue_kobj, KOBJ_REMOVE); 913 kobject_del(&disk->queue_kobj); 914 mutex_unlock(&q->sysfs_dir_lock); 915 916 blk_debugfs_remove(disk); 917 } 918