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_var_store64(s64 *var, const char *page) 51 { 52 int err; 53 s64 v; 54 55 err = kstrtos64(page, 10, &v); 56 if (err < 0) 57 return err; 58 59 *var = v; 60 return 0; 61 } 62 63 static ssize_t queue_requests_show(struct request_queue *q, char *page) 64 { 65 return queue_var_show(q->nr_requests, page); 66 } 67 68 static ssize_t 69 queue_requests_store(struct request_queue *q, const char *page, size_t count) 70 { 71 unsigned long nr; 72 int ret, err; 73 74 if (!queue_is_mq(q)) 75 return -EINVAL; 76 77 ret = queue_var_store(&nr, page, count); 78 if (ret < 0) 79 return ret; 80 81 if (nr < BLKDEV_MIN_RQ) 82 nr = BLKDEV_MIN_RQ; 83 84 err = blk_mq_update_nr_requests(q, nr); 85 if (err) 86 return err; 87 88 return ret; 89 } 90 91 static ssize_t queue_ra_show(struct request_queue *q, char *page) 92 { 93 unsigned long ra_kb; 94 95 if (!q->disk) 96 return -EINVAL; 97 ra_kb = q->disk->bdi->ra_pages << (PAGE_SHIFT - 10); 98 return queue_var_show(ra_kb, page); 99 } 100 101 static ssize_t 102 queue_ra_store(struct request_queue *q, const char *page, size_t count) 103 { 104 unsigned long ra_kb; 105 ssize_t ret; 106 107 if (!q->disk) 108 return -EINVAL; 109 ret = queue_var_store(&ra_kb, page, count); 110 if (ret < 0) 111 return ret; 112 q->disk->bdi->ra_pages = ra_kb >> (PAGE_SHIFT - 10); 113 return ret; 114 } 115 116 static ssize_t queue_max_sectors_show(struct request_queue *q, char *page) 117 { 118 int max_sectors_kb = queue_max_sectors(q) >> 1; 119 120 return queue_var_show(max_sectors_kb, page); 121 } 122 123 static ssize_t queue_max_segments_show(struct request_queue *q, char *page) 124 { 125 return queue_var_show(queue_max_segments(q), page); 126 } 127 128 static ssize_t queue_max_discard_segments_show(struct request_queue *q, 129 char *page) 130 { 131 return queue_var_show(queue_max_discard_segments(q), page); 132 } 133 134 static ssize_t queue_max_integrity_segments_show(struct request_queue *q, char *page) 135 { 136 return queue_var_show(q->limits.max_integrity_segments, page); 137 } 138 139 static ssize_t queue_max_segment_size_show(struct request_queue *q, char *page) 140 { 141 return queue_var_show(queue_max_segment_size(q), page); 142 } 143 144 static ssize_t queue_logical_block_size_show(struct request_queue *q, char *page) 145 { 146 return queue_var_show(queue_logical_block_size(q), page); 147 } 148 149 static ssize_t queue_physical_block_size_show(struct request_queue *q, char *page) 150 { 151 return queue_var_show(queue_physical_block_size(q), page); 152 } 153 154 static ssize_t queue_chunk_sectors_show(struct request_queue *q, char *page) 155 { 156 return queue_var_show(q->limits.chunk_sectors, page); 157 } 158 159 static ssize_t queue_io_min_show(struct request_queue *q, char *page) 160 { 161 return queue_var_show(queue_io_min(q), page); 162 } 163 164 static ssize_t queue_io_opt_show(struct request_queue *q, char *page) 165 { 166 return queue_var_show(queue_io_opt(q), page); 167 } 168 169 static ssize_t queue_discard_granularity_show(struct request_queue *q, char *page) 170 { 171 return queue_var_show(q->limits.discard_granularity, page); 172 } 173 174 static ssize_t queue_discard_max_hw_show(struct request_queue *q, char *page) 175 { 176 177 return sprintf(page, "%llu\n", 178 (unsigned long long)q->limits.max_hw_discard_sectors << 9); 179 } 180 181 static ssize_t queue_discard_max_show(struct request_queue *q, char *page) 182 { 183 return sprintf(page, "%llu\n", 184 (unsigned long long)q->limits.max_discard_sectors << 9); 185 } 186 187 static ssize_t queue_discard_max_store(struct request_queue *q, 188 const char *page, size_t count) 189 { 190 unsigned long max_discard; 191 ssize_t ret = queue_var_store(&max_discard, page, count); 192 193 if (ret < 0) 194 return ret; 195 196 if (max_discard & (q->limits.discard_granularity - 1)) 197 return -EINVAL; 198 199 max_discard >>= 9; 200 if (max_discard > UINT_MAX) 201 return -EINVAL; 202 203 if (max_discard > q->limits.max_hw_discard_sectors) 204 max_discard = q->limits.max_hw_discard_sectors; 205 206 q->limits.max_discard_sectors = max_discard; 207 return ret; 208 } 209 210 static ssize_t queue_discard_zeroes_data_show(struct request_queue *q, char *page) 211 { 212 return queue_var_show(0, page); 213 } 214 215 static ssize_t queue_write_same_max_show(struct request_queue *q, char *page) 216 { 217 return queue_var_show(0, page); 218 } 219 220 static ssize_t queue_write_zeroes_max_show(struct request_queue *q, char *page) 221 { 222 return sprintf(page, "%llu\n", 223 (unsigned long long)q->limits.max_write_zeroes_sectors << 9); 224 } 225 226 static ssize_t queue_zone_write_granularity_show(struct request_queue *q, 227 char *page) 228 { 229 return queue_var_show(queue_zone_write_granularity(q), page); 230 } 231 232 static ssize_t queue_zone_append_max_show(struct request_queue *q, char *page) 233 { 234 unsigned long long max_sectors = q->limits.max_zone_append_sectors; 235 236 return sprintf(page, "%llu\n", max_sectors << SECTOR_SHIFT); 237 } 238 239 static ssize_t 240 queue_max_sectors_store(struct request_queue *q, const char *page, size_t count) 241 { 242 unsigned long var; 243 unsigned int max_sectors_kb, 244 max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1, 245 page_kb = 1 << (PAGE_SHIFT - 10); 246 ssize_t ret = queue_var_store(&var, page, count); 247 248 if (ret < 0) 249 return ret; 250 251 max_sectors_kb = (unsigned int)var; 252 max_hw_sectors_kb = min_not_zero(max_hw_sectors_kb, 253 q->limits.max_dev_sectors >> 1); 254 if (max_sectors_kb == 0) { 255 q->limits.max_user_sectors = 0; 256 max_sectors_kb = min(max_hw_sectors_kb, 257 BLK_DEF_MAX_SECTORS >> 1); 258 } else { 259 if (max_sectors_kb > max_hw_sectors_kb || 260 max_sectors_kb < page_kb) 261 return -EINVAL; 262 q->limits.max_user_sectors = max_sectors_kb << 1; 263 } 264 265 spin_lock_irq(&q->queue_lock); 266 q->limits.max_sectors = max_sectors_kb << 1; 267 if (q->disk) 268 q->disk->bdi->io_pages = max_sectors_kb >> (PAGE_SHIFT - 10); 269 spin_unlock_irq(&q->queue_lock); 270 271 return ret; 272 } 273 274 static ssize_t queue_max_hw_sectors_show(struct request_queue *q, char *page) 275 { 276 int max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1; 277 278 return queue_var_show(max_hw_sectors_kb, page); 279 } 280 281 static ssize_t queue_virt_boundary_mask_show(struct request_queue *q, char *page) 282 { 283 return queue_var_show(q->limits.virt_boundary_mask, page); 284 } 285 286 static ssize_t queue_dma_alignment_show(struct request_queue *q, char *page) 287 { 288 return queue_var_show(queue_dma_alignment(q), page); 289 } 290 291 #define QUEUE_SYSFS_BIT_FNS(name, flag, neg) \ 292 static ssize_t \ 293 queue_##name##_show(struct request_queue *q, char *page) \ 294 { \ 295 int bit; \ 296 bit = test_bit(QUEUE_FLAG_##flag, &q->queue_flags); \ 297 return queue_var_show(neg ? !bit : bit, page); \ 298 } \ 299 static ssize_t \ 300 queue_##name##_store(struct request_queue *q, const char *page, size_t count) \ 301 { \ 302 unsigned long val; \ 303 ssize_t ret; \ 304 ret = queue_var_store(&val, page, count); \ 305 if (ret < 0) \ 306 return ret; \ 307 if (neg) \ 308 val = !val; \ 309 \ 310 if (val) \ 311 blk_queue_flag_set(QUEUE_FLAG_##flag, q); \ 312 else \ 313 blk_queue_flag_clear(QUEUE_FLAG_##flag, q); \ 314 return ret; \ 315 } 316 317 QUEUE_SYSFS_BIT_FNS(nonrot, NONROT, 1); 318 QUEUE_SYSFS_BIT_FNS(random, ADD_RANDOM, 0); 319 QUEUE_SYSFS_BIT_FNS(iostats, IO_STAT, 0); 320 QUEUE_SYSFS_BIT_FNS(stable_writes, STABLE_WRITES, 0); 321 #undef QUEUE_SYSFS_BIT_FNS 322 323 static ssize_t queue_zoned_show(struct request_queue *q, char *page) 324 { 325 switch (blk_queue_zoned_model(q)) { 326 case BLK_ZONED_HA: 327 return sprintf(page, "host-aware\n"); 328 case BLK_ZONED_HM: 329 return sprintf(page, "host-managed\n"); 330 default: 331 return sprintf(page, "none\n"); 332 } 333 } 334 335 static ssize_t queue_nr_zones_show(struct request_queue *q, char *page) 336 { 337 return queue_var_show(disk_nr_zones(q->disk), page); 338 } 339 340 static ssize_t queue_max_open_zones_show(struct request_queue *q, char *page) 341 { 342 return queue_var_show(bdev_max_open_zones(q->disk->part0), page); 343 } 344 345 static ssize_t queue_max_active_zones_show(struct request_queue *q, char *page) 346 { 347 return queue_var_show(bdev_max_active_zones(q->disk->part0), page); 348 } 349 350 static ssize_t queue_nomerges_show(struct request_queue *q, char *page) 351 { 352 return queue_var_show((blk_queue_nomerges(q) << 1) | 353 blk_queue_noxmerges(q), page); 354 } 355 356 static ssize_t queue_nomerges_store(struct request_queue *q, const char *page, 357 size_t count) 358 { 359 unsigned long nm; 360 ssize_t ret = queue_var_store(&nm, page, count); 361 362 if (ret < 0) 363 return ret; 364 365 blk_queue_flag_clear(QUEUE_FLAG_NOMERGES, q); 366 blk_queue_flag_clear(QUEUE_FLAG_NOXMERGES, q); 367 if (nm == 2) 368 blk_queue_flag_set(QUEUE_FLAG_NOMERGES, q); 369 else if (nm) 370 blk_queue_flag_set(QUEUE_FLAG_NOXMERGES, q); 371 372 return ret; 373 } 374 375 static ssize_t queue_rq_affinity_show(struct request_queue *q, char *page) 376 { 377 bool set = test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags); 378 bool force = test_bit(QUEUE_FLAG_SAME_FORCE, &q->queue_flags); 379 380 return queue_var_show(set << force, page); 381 } 382 383 static ssize_t 384 queue_rq_affinity_store(struct request_queue *q, const char *page, size_t count) 385 { 386 ssize_t ret = -EINVAL; 387 #ifdef CONFIG_SMP 388 unsigned long val; 389 390 ret = queue_var_store(&val, page, count); 391 if (ret < 0) 392 return ret; 393 394 if (val == 2) { 395 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q); 396 blk_queue_flag_set(QUEUE_FLAG_SAME_FORCE, q); 397 } else if (val == 1) { 398 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q); 399 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q); 400 } else if (val == 0) { 401 blk_queue_flag_clear(QUEUE_FLAG_SAME_COMP, q); 402 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q); 403 } 404 #endif 405 return ret; 406 } 407 408 static ssize_t queue_poll_delay_show(struct request_queue *q, char *page) 409 { 410 return sprintf(page, "%d\n", -1); 411 } 412 413 static ssize_t queue_poll_delay_store(struct request_queue *q, const char *page, 414 size_t count) 415 { 416 return count; 417 } 418 419 static ssize_t queue_poll_show(struct request_queue *q, char *page) 420 { 421 return queue_var_show(test_bit(QUEUE_FLAG_POLL, &q->queue_flags), page); 422 } 423 424 static ssize_t queue_poll_store(struct request_queue *q, const char *page, 425 size_t count) 426 { 427 if (!test_bit(QUEUE_FLAG_POLL, &q->queue_flags)) 428 return -EINVAL; 429 pr_info_ratelimited("writes to the poll attribute are ignored.\n"); 430 pr_info_ratelimited("please use driver specific parameters instead.\n"); 431 return count; 432 } 433 434 static ssize_t queue_io_timeout_show(struct request_queue *q, char *page) 435 { 436 return sprintf(page, "%u\n", jiffies_to_msecs(q->rq_timeout)); 437 } 438 439 static ssize_t queue_io_timeout_store(struct request_queue *q, const char *page, 440 size_t count) 441 { 442 unsigned int val; 443 int err; 444 445 err = kstrtou32(page, 10, &val); 446 if (err || val == 0) 447 return -EINVAL; 448 449 blk_queue_rq_timeout(q, msecs_to_jiffies(val)); 450 451 return count; 452 } 453 454 static ssize_t queue_wb_lat_show(struct request_queue *q, char *page) 455 { 456 if (!wbt_rq_qos(q)) 457 return -EINVAL; 458 459 if (wbt_disabled(q)) 460 return sprintf(page, "0\n"); 461 462 return sprintf(page, "%llu\n", div_u64(wbt_get_min_lat(q), 1000)); 463 } 464 465 static ssize_t queue_wb_lat_store(struct request_queue *q, const char *page, 466 size_t count) 467 { 468 struct rq_qos *rqos; 469 ssize_t ret; 470 s64 val; 471 472 ret = queue_var_store64(&val, page); 473 if (ret < 0) 474 return ret; 475 if (val < -1) 476 return -EINVAL; 477 478 rqos = wbt_rq_qos(q); 479 if (!rqos) { 480 ret = wbt_init(q->disk); 481 if (ret) 482 return ret; 483 } 484 485 if (val == -1) 486 val = wbt_default_latency_nsec(q); 487 else if (val >= 0) 488 val *= 1000ULL; 489 490 if (wbt_get_min_lat(q) == val) 491 return count; 492 493 /* 494 * Ensure that the queue is idled, in case the latency update 495 * ends up either enabling or disabling wbt completely. We can't 496 * have IO inflight if that happens. 497 */ 498 blk_mq_freeze_queue(q); 499 blk_mq_quiesce_queue(q); 500 501 wbt_set_min_lat(q, val); 502 503 blk_mq_unquiesce_queue(q); 504 blk_mq_unfreeze_queue(q); 505 506 return count; 507 } 508 509 static ssize_t queue_wc_show(struct request_queue *q, char *page) 510 { 511 if (test_bit(QUEUE_FLAG_WC, &q->queue_flags)) 512 return sprintf(page, "write back\n"); 513 514 return sprintf(page, "write through\n"); 515 } 516 517 static ssize_t queue_wc_store(struct request_queue *q, const char *page, 518 size_t count) 519 { 520 int set = -1; 521 522 if (!strncmp(page, "write back", 10)) 523 set = 1; 524 else if (!strncmp(page, "write through", 13) || 525 !strncmp(page, "none", 4)) 526 set = 0; 527 528 if (set == -1) 529 return -EINVAL; 530 531 if (set) 532 blk_queue_flag_set(QUEUE_FLAG_WC, q); 533 else 534 blk_queue_flag_clear(QUEUE_FLAG_WC, q); 535 536 return count; 537 } 538 539 static ssize_t queue_fua_show(struct request_queue *q, char *page) 540 { 541 return sprintf(page, "%u\n", test_bit(QUEUE_FLAG_FUA, &q->queue_flags)); 542 } 543 544 static ssize_t queue_dax_show(struct request_queue *q, char *page) 545 { 546 return queue_var_show(blk_queue_dax(q), page); 547 } 548 549 #define QUEUE_RO_ENTRY(_prefix, _name) \ 550 static struct queue_sysfs_entry _prefix##_entry = { \ 551 .attr = { .name = _name, .mode = 0444 }, \ 552 .show = _prefix##_show, \ 553 }; 554 555 #define QUEUE_RW_ENTRY(_prefix, _name) \ 556 static struct queue_sysfs_entry _prefix##_entry = { \ 557 .attr = { .name = _name, .mode = 0644 }, \ 558 .show = _prefix##_show, \ 559 .store = _prefix##_store, \ 560 }; 561 562 QUEUE_RW_ENTRY(queue_requests, "nr_requests"); 563 QUEUE_RW_ENTRY(queue_ra, "read_ahead_kb"); 564 QUEUE_RW_ENTRY(queue_max_sectors, "max_sectors_kb"); 565 QUEUE_RO_ENTRY(queue_max_hw_sectors, "max_hw_sectors_kb"); 566 QUEUE_RO_ENTRY(queue_max_segments, "max_segments"); 567 QUEUE_RO_ENTRY(queue_max_integrity_segments, "max_integrity_segments"); 568 QUEUE_RO_ENTRY(queue_max_segment_size, "max_segment_size"); 569 QUEUE_RW_ENTRY(elv_iosched, "scheduler"); 570 571 QUEUE_RO_ENTRY(queue_logical_block_size, "logical_block_size"); 572 QUEUE_RO_ENTRY(queue_physical_block_size, "physical_block_size"); 573 QUEUE_RO_ENTRY(queue_chunk_sectors, "chunk_sectors"); 574 QUEUE_RO_ENTRY(queue_io_min, "minimum_io_size"); 575 QUEUE_RO_ENTRY(queue_io_opt, "optimal_io_size"); 576 577 QUEUE_RO_ENTRY(queue_max_discard_segments, "max_discard_segments"); 578 QUEUE_RO_ENTRY(queue_discard_granularity, "discard_granularity"); 579 QUEUE_RO_ENTRY(queue_discard_max_hw, "discard_max_hw_bytes"); 580 QUEUE_RW_ENTRY(queue_discard_max, "discard_max_bytes"); 581 QUEUE_RO_ENTRY(queue_discard_zeroes_data, "discard_zeroes_data"); 582 583 QUEUE_RO_ENTRY(queue_write_same_max, "write_same_max_bytes"); 584 QUEUE_RO_ENTRY(queue_write_zeroes_max, "write_zeroes_max_bytes"); 585 QUEUE_RO_ENTRY(queue_zone_append_max, "zone_append_max_bytes"); 586 QUEUE_RO_ENTRY(queue_zone_write_granularity, "zone_write_granularity"); 587 588 QUEUE_RO_ENTRY(queue_zoned, "zoned"); 589 QUEUE_RO_ENTRY(queue_nr_zones, "nr_zones"); 590 QUEUE_RO_ENTRY(queue_max_open_zones, "max_open_zones"); 591 QUEUE_RO_ENTRY(queue_max_active_zones, "max_active_zones"); 592 593 QUEUE_RW_ENTRY(queue_nomerges, "nomerges"); 594 QUEUE_RW_ENTRY(queue_rq_affinity, "rq_affinity"); 595 QUEUE_RW_ENTRY(queue_poll, "io_poll"); 596 QUEUE_RW_ENTRY(queue_poll_delay, "io_poll_delay"); 597 QUEUE_RW_ENTRY(queue_wc, "write_cache"); 598 QUEUE_RO_ENTRY(queue_fua, "fua"); 599 QUEUE_RO_ENTRY(queue_dax, "dax"); 600 QUEUE_RW_ENTRY(queue_io_timeout, "io_timeout"); 601 QUEUE_RW_ENTRY(queue_wb_lat, "wbt_lat_usec"); 602 QUEUE_RO_ENTRY(queue_virt_boundary_mask, "virt_boundary_mask"); 603 QUEUE_RO_ENTRY(queue_dma_alignment, "dma_alignment"); 604 605 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW 606 QUEUE_RW_ENTRY(blk_throtl_sample_time, "throttle_sample_time"); 607 #endif 608 609 /* legacy alias for logical_block_size: */ 610 static struct queue_sysfs_entry queue_hw_sector_size_entry = { 611 .attr = {.name = "hw_sector_size", .mode = 0444 }, 612 .show = queue_logical_block_size_show, 613 }; 614 615 QUEUE_RW_ENTRY(queue_nonrot, "rotational"); 616 QUEUE_RW_ENTRY(queue_iostats, "iostats"); 617 QUEUE_RW_ENTRY(queue_random, "add_random"); 618 QUEUE_RW_ENTRY(queue_stable_writes, "stable_writes"); 619 620 static struct attribute *queue_attrs[] = { 621 &queue_requests_entry.attr, 622 &queue_ra_entry.attr, 623 &queue_max_hw_sectors_entry.attr, 624 &queue_max_sectors_entry.attr, 625 &queue_max_segments_entry.attr, 626 &queue_max_discard_segments_entry.attr, 627 &queue_max_integrity_segments_entry.attr, 628 &queue_max_segment_size_entry.attr, 629 &elv_iosched_entry.attr, 630 &queue_hw_sector_size_entry.attr, 631 &queue_logical_block_size_entry.attr, 632 &queue_physical_block_size_entry.attr, 633 &queue_chunk_sectors_entry.attr, 634 &queue_io_min_entry.attr, 635 &queue_io_opt_entry.attr, 636 &queue_discard_granularity_entry.attr, 637 &queue_discard_max_entry.attr, 638 &queue_discard_max_hw_entry.attr, 639 &queue_discard_zeroes_data_entry.attr, 640 &queue_write_same_max_entry.attr, 641 &queue_write_zeroes_max_entry.attr, 642 &queue_zone_append_max_entry.attr, 643 &queue_zone_write_granularity_entry.attr, 644 &queue_nonrot_entry.attr, 645 &queue_zoned_entry.attr, 646 &queue_nr_zones_entry.attr, 647 &queue_max_open_zones_entry.attr, 648 &queue_max_active_zones_entry.attr, 649 &queue_nomerges_entry.attr, 650 &queue_rq_affinity_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_wb_lat_entry.attr, 659 &queue_poll_delay_entry.attr, 660 &queue_io_timeout_entry.attr, 661 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW 662 &blk_throtl_sample_time_entry.attr, 663 #endif 664 &queue_virt_boundary_mask_entry.attr, 665 &queue_dma_alignment_entry.attr, 666 NULL, 667 }; 668 669 static umode_t queue_attr_visible(struct kobject *kobj, struct attribute *attr, 670 int n) 671 { 672 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 673 struct request_queue *q = disk->queue; 674 675 if (attr == &queue_io_timeout_entry.attr && 676 (!q->mq_ops || !q->mq_ops->timeout)) 677 return 0; 678 679 if ((attr == &queue_max_open_zones_entry.attr || 680 attr == &queue_max_active_zones_entry.attr) && 681 !blk_queue_is_zoned(q)) 682 return 0; 683 684 return attr->mode; 685 } 686 687 static struct attribute_group queue_attr_group = { 688 .attrs = queue_attrs, 689 .is_visible = queue_attr_visible, 690 }; 691 692 693 #define to_queue(atr) container_of((atr), struct queue_sysfs_entry, attr) 694 695 static ssize_t 696 queue_attr_show(struct kobject *kobj, struct attribute *attr, char *page) 697 { 698 struct queue_sysfs_entry *entry = to_queue(attr); 699 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 700 struct request_queue *q = disk->queue; 701 ssize_t res; 702 703 if (!entry->show) 704 return -EIO; 705 mutex_lock(&q->sysfs_lock); 706 res = entry->show(q, page); 707 mutex_unlock(&q->sysfs_lock); 708 return res; 709 } 710 711 static ssize_t 712 queue_attr_store(struct kobject *kobj, struct attribute *attr, 713 const char *page, size_t length) 714 { 715 struct queue_sysfs_entry *entry = to_queue(attr); 716 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 717 struct request_queue *q = disk->queue; 718 ssize_t res; 719 720 if (!entry->store) 721 return -EIO; 722 723 mutex_lock(&q->sysfs_lock); 724 res = entry->store(q, page, length); 725 mutex_unlock(&q->sysfs_lock); 726 return res; 727 } 728 729 static const struct sysfs_ops queue_sysfs_ops = { 730 .show = queue_attr_show, 731 .store = queue_attr_store, 732 }; 733 734 static const struct attribute_group *blk_queue_attr_groups[] = { 735 &queue_attr_group, 736 NULL 737 }; 738 739 static void blk_queue_release(struct kobject *kobj) 740 { 741 /* nothing to do here, all data is associated with the parent gendisk */ 742 } 743 744 static const struct kobj_type blk_queue_ktype = { 745 .default_groups = blk_queue_attr_groups, 746 .sysfs_ops = &queue_sysfs_ops, 747 .release = blk_queue_release, 748 }; 749 750 static void blk_debugfs_remove(struct gendisk *disk) 751 { 752 struct request_queue *q = disk->queue; 753 754 mutex_lock(&q->debugfs_mutex); 755 blk_trace_shutdown(q); 756 debugfs_remove_recursive(q->debugfs_dir); 757 q->debugfs_dir = NULL; 758 q->sched_debugfs_dir = NULL; 759 q->rqos_debugfs_dir = NULL; 760 mutex_unlock(&q->debugfs_mutex); 761 } 762 763 /** 764 * blk_register_queue - register a block layer queue with sysfs 765 * @disk: Disk of which the request queue should be registered with sysfs. 766 */ 767 int blk_register_queue(struct gendisk *disk) 768 { 769 struct request_queue *q = disk->queue; 770 int ret; 771 772 mutex_lock(&q->sysfs_dir_lock); 773 kobject_init(&disk->queue_kobj, &blk_queue_ktype); 774 ret = kobject_add(&disk->queue_kobj, &disk_to_dev(disk)->kobj, "queue"); 775 if (ret < 0) 776 goto out_put_queue_kobj; 777 778 if (queue_is_mq(q)) { 779 ret = blk_mq_sysfs_register(disk); 780 if (ret) 781 goto out_put_queue_kobj; 782 } 783 mutex_lock(&q->sysfs_lock); 784 785 mutex_lock(&q->debugfs_mutex); 786 q->debugfs_dir = debugfs_create_dir(disk->disk_name, blk_debugfs_root); 787 if (queue_is_mq(q)) 788 blk_mq_debugfs_register(q); 789 mutex_unlock(&q->debugfs_mutex); 790 791 ret = disk_register_independent_access_ranges(disk); 792 if (ret) 793 goto out_debugfs_remove; 794 795 if (q->elevator) { 796 ret = elv_register_queue(q, false); 797 if (ret) 798 goto out_unregister_ia_ranges; 799 } 800 801 ret = blk_crypto_sysfs_register(disk); 802 if (ret) 803 goto out_elv_unregister; 804 805 blk_queue_flag_set(QUEUE_FLAG_REGISTERED, q); 806 wbt_enable_default(disk); 807 blk_throtl_register(disk); 808 809 /* Now everything is ready and send out KOBJ_ADD uevent */ 810 kobject_uevent(&disk->queue_kobj, KOBJ_ADD); 811 if (q->elevator) 812 kobject_uevent(&q->elevator->kobj, KOBJ_ADD); 813 mutex_unlock(&q->sysfs_lock); 814 mutex_unlock(&q->sysfs_dir_lock); 815 816 /* 817 * SCSI probing may synchronously create and destroy a lot of 818 * request_queues for non-existent devices. Shutting down a fully 819 * functional queue takes measureable wallclock time as RCU grace 820 * periods are involved. To avoid excessive latency in these 821 * cases, a request_queue starts out in a degraded mode which is 822 * faster to shut down and is made fully functional here as 823 * request_queues for non-existent devices never get registered. 824 */ 825 if (!blk_queue_init_done(q)) { 826 blk_queue_flag_set(QUEUE_FLAG_INIT_DONE, q); 827 percpu_ref_switch_to_percpu(&q->q_usage_counter); 828 } 829 830 return ret; 831 832 out_elv_unregister: 833 elv_unregister_queue(q); 834 out_unregister_ia_ranges: 835 disk_unregister_independent_access_ranges(disk); 836 out_debugfs_remove: 837 blk_debugfs_remove(disk); 838 mutex_unlock(&q->sysfs_lock); 839 out_put_queue_kobj: 840 kobject_put(&disk->queue_kobj); 841 mutex_unlock(&q->sysfs_dir_lock); 842 return ret; 843 } 844 845 /** 846 * blk_unregister_queue - counterpart of blk_register_queue() 847 * @disk: Disk of which the request queue should be unregistered from sysfs. 848 * 849 * Note: the caller is responsible for guaranteeing that this function is called 850 * after blk_register_queue() has finished. 851 */ 852 void blk_unregister_queue(struct gendisk *disk) 853 { 854 struct request_queue *q = disk->queue; 855 856 if (WARN_ON(!q)) 857 return; 858 859 /* Return early if disk->queue was never registered. */ 860 if (!blk_queue_registered(q)) 861 return; 862 863 /* 864 * Since sysfs_remove_dir() prevents adding new directory entries 865 * before removal of existing entries starts, protect against 866 * concurrent elv_iosched_store() calls. 867 */ 868 mutex_lock(&q->sysfs_lock); 869 blk_queue_flag_clear(QUEUE_FLAG_REGISTERED, q); 870 mutex_unlock(&q->sysfs_lock); 871 872 mutex_lock(&q->sysfs_dir_lock); 873 /* 874 * Remove the sysfs attributes before unregistering the queue data 875 * structures that can be modified through sysfs. 876 */ 877 if (queue_is_mq(q)) 878 blk_mq_sysfs_unregister(disk); 879 blk_crypto_sysfs_unregister(disk); 880 881 mutex_lock(&q->sysfs_lock); 882 elv_unregister_queue(q); 883 disk_unregister_independent_access_ranges(disk); 884 mutex_unlock(&q->sysfs_lock); 885 886 /* Now that we've deleted all child objects, we can delete the queue. */ 887 kobject_uevent(&disk->queue_kobj, KOBJ_REMOVE); 888 kobject_del(&disk->queue_kobj); 889 mutex_unlock(&q->sysfs_dir_lock); 890 891 blk_debugfs_remove(disk); 892 } 893