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 gendisk *disk, char *page); 26 ssize_t (*store)(struct gendisk *disk, const char *page, size_t count); 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 gendisk *disk, char *page) 51 { 52 return queue_var_show(disk->queue->nr_requests, page); 53 } 54 55 static ssize_t 56 queue_requests_store(struct gendisk *disk, const char *page, size_t count) 57 { 58 unsigned long nr; 59 int ret, err; 60 61 if (!queue_is_mq(disk->queue)) 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(disk->queue, nr); 72 if (err) 73 return err; 74 75 return ret; 76 } 77 78 static ssize_t queue_ra_show(struct gendisk *disk, char *page) 79 { 80 return queue_var_show(disk->bdi->ra_pages << (PAGE_SHIFT - 10), page); 81 } 82 83 static ssize_t 84 queue_ra_store(struct gendisk *disk, const char *page, size_t count) 85 { 86 unsigned long ra_kb; 87 ssize_t ret; 88 89 ret = queue_var_store(&ra_kb, page, count); 90 if (ret < 0) 91 return ret; 92 disk->bdi->ra_pages = ra_kb >> (PAGE_SHIFT - 10); 93 return ret; 94 } 95 96 #define QUEUE_SYSFS_LIMIT_SHOW(_field) \ 97 static ssize_t queue_##_field##_show(struct gendisk *disk, char *page) \ 98 { \ 99 return queue_var_show(disk->queue->limits._field, page); \ 100 } 101 102 QUEUE_SYSFS_LIMIT_SHOW(max_segments) 103 QUEUE_SYSFS_LIMIT_SHOW(max_discard_segments) 104 QUEUE_SYSFS_LIMIT_SHOW(max_integrity_segments) 105 QUEUE_SYSFS_LIMIT_SHOW(max_segment_size) 106 QUEUE_SYSFS_LIMIT_SHOW(logical_block_size) 107 QUEUE_SYSFS_LIMIT_SHOW(physical_block_size) 108 QUEUE_SYSFS_LIMIT_SHOW(chunk_sectors) 109 QUEUE_SYSFS_LIMIT_SHOW(io_min) 110 QUEUE_SYSFS_LIMIT_SHOW(io_opt) 111 QUEUE_SYSFS_LIMIT_SHOW(discard_granularity) 112 QUEUE_SYSFS_LIMIT_SHOW(zone_write_granularity) 113 QUEUE_SYSFS_LIMIT_SHOW(virt_boundary_mask) 114 QUEUE_SYSFS_LIMIT_SHOW(dma_alignment) 115 QUEUE_SYSFS_LIMIT_SHOW(max_open_zones) 116 QUEUE_SYSFS_LIMIT_SHOW(max_active_zones) 117 QUEUE_SYSFS_LIMIT_SHOW(atomic_write_unit_min) 118 QUEUE_SYSFS_LIMIT_SHOW(atomic_write_unit_max) 119 120 #define QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(_field) \ 121 static ssize_t queue_##_field##_show(struct gendisk *disk, char *page) \ 122 { \ 123 return sprintf(page, "%llu\n", \ 124 (unsigned long long)disk->queue->limits._field << \ 125 SECTOR_SHIFT); \ 126 } 127 128 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(max_discard_sectors) 129 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(max_hw_discard_sectors) 130 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(max_write_zeroes_sectors) 131 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(atomic_write_max_sectors) 132 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(atomic_write_boundary_sectors) 133 134 #define QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_KB(_field) \ 135 static ssize_t queue_##_field##_show(struct gendisk *disk, char *page) \ 136 { \ 137 return queue_var_show(disk->queue->limits._field >> 1, page); \ 138 } 139 140 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_KB(max_sectors) 141 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_KB(max_hw_sectors) 142 143 #define QUEUE_SYSFS_SHOW_CONST(_name, _val) \ 144 static ssize_t queue_##_name##_show(struct gendisk *disk, char *page) \ 145 { \ 146 return sprintf(page, "%d\n", _val); \ 147 } 148 149 /* deprecated fields */ 150 QUEUE_SYSFS_SHOW_CONST(discard_zeroes_data, 0) 151 QUEUE_SYSFS_SHOW_CONST(write_same_max, 0) 152 QUEUE_SYSFS_SHOW_CONST(poll_delay, -1) 153 154 static ssize_t queue_max_discard_sectors_store(struct gendisk *disk, 155 const char *page, size_t count) 156 { 157 unsigned long max_discard_bytes; 158 struct queue_limits lim; 159 ssize_t ret; 160 int err; 161 162 ret = queue_var_store(&max_discard_bytes, page, count); 163 if (ret < 0) 164 return ret; 165 166 if (max_discard_bytes & (disk->queue->limits.discard_granularity - 1)) 167 return -EINVAL; 168 169 if ((max_discard_bytes >> SECTOR_SHIFT) > UINT_MAX) 170 return -EINVAL; 171 172 lim = queue_limits_start_update(disk->queue); 173 lim.max_user_discard_sectors = max_discard_bytes >> SECTOR_SHIFT; 174 err = queue_limits_commit_update(disk->queue, &lim); 175 if (err) 176 return err; 177 return ret; 178 } 179 180 /* 181 * For zone append queue_max_zone_append_sectors does not just return the 182 * underlying queue limits, but actually contains a calculation. Because of 183 * that we can't simply use QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES here. 184 */ 185 static ssize_t queue_zone_append_max_show(struct gendisk *disk, char *page) 186 { 187 return sprintf(page, "%llu\n", 188 (u64)queue_max_zone_append_sectors(disk->queue) << 189 SECTOR_SHIFT); 190 } 191 192 static ssize_t 193 queue_max_sectors_store(struct gendisk *disk, const char *page, size_t count) 194 { 195 unsigned long max_sectors_kb; 196 struct queue_limits lim; 197 ssize_t ret; 198 int err; 199 200 ret = queue_var_store(&max_sectors_kb, page, count); 201 if (ret < 0) 202 return ret; 203 204 lim = queue_limits_start_update(disk->queue); 205 lim.max_user_sectors = max_sectors_kb << 1; 206 err = queue_limits_commit_update(disk->queue, &lim); 207 if (err) 208 return err; 209 return ret; 210 } 211 212 static ssize_t queue_feature_store(struct gendisk *disk, const char *page, 213 size_t count, blk_features_t feature) 214 { 215 struct queue_limits lim; 216 unsigned long val; 217 ssize_t ret; 218 219 ret = queue_var_store(&val, page, count); 220 if (ret < 0) 221 return ret; 222 223 lim = queue_limits_start_update(disk->queue); 224 if (val) 225 lim.features |= feature; 226 else 227 lim.features &= ~feature; 228 ret = queue_limits_commit_update(disk->queue, &lim); 229 if (ret) 230 return ret; 231 return count; 232 } 233 234 #define QUEUE_SYSFS_FEATURE(_name, _feature) \ 235 static ssize_t queue_##_name##_show(struct gendisk *disk, char *page) \ 236 { \ 237 return sprintf(page, "%u\n", \ 238 !!(disk->queue->limits.features & _feature)); \ 239 } \ 240 static ssize_t queue_##_name##_store(struct gendisk *disk, \ 241 const char *page, size_t count) \ 242 { \ 243 return queue_feature_store(disk, page, count, _feature); \ 244 } 245 246 QUEUE_SYSFS_FEATURE(rotational, BLK_FEAT_ROTATIONAL) 247 QUEUE_SYSFS_FEATURE(add_random, BLK_FEAT_ADD_RANDOM) 248 QUEUE_SYSFS_FEATURE(iostats, BLK_FEAT_IO_STAT) 249 QUEUE_SYSFS_FEATURE(stable_writes, BLK_FEAT_STABLE_WRITES); 250 251 #define QUEUE_SYSFS_FEATURE_SHOW(_name, _feature) \ 252 static ssize_t queue_##_name##_show(struct gendisk *disk, char *page) \ 253 { \ 254 return sprintf(page, "%u\n", \ 255 !!(disk->queue->limits.features & _feature)); \ 256 } 257 258 QUEUE_SYSFS_FEATURE_SHOW(poll, BLK_FEAT_POLL); 259 QUEUE_SYSFS_FEATURE_SHOW(fua, BLK_FEAT_FUA); 260 QUEUE_SYSFS_FEATURE_SHOW(dax, BLK_FEAT_DAX); 261 262 static ssize_t queue_zoned_show(struct gendisk *disk, char *page) 263 { 264 if (blk_queue_is_zoned(disk->queue)) 265 return sprintf(page, "host-managed\n"); 266 return sprintf(page, "none\n"); 267 } 268 269 static ssize_t queue_nr_zones_show(struct gendisk *disk, char *page) 270 { 271 return queue_var_show(disk_nr_zones(disk), page); 272 } 273 274 static ssize_t queue_nomerges_show(struct gendisk *disk, char *page) 275 { 276 return queue_var_show((blk_queue_nomerges(disk->queue) << 1) | 277 blk_queue_noxmerges(disk->queue), page); 278 } 279 280 static ssize_t queue_nomerges_store(struct gendisk *disk, const char *page, 281 size_t count) 282 { 283 unsigned long nm; 284 ssize_t ret = queue_var_store(&nm, page, count); 285 286 if (ret < 0) 287 return ret; 288 289 blk_queue_flag_clear(QUEUE_FLAG_NOMERGES, disk->queue); 290 blk_queue_flag_clear(QUEUE_FLAG_NOXMERGES, disk->queue); 291 if (nm == 2) 292 blk_queue_flag_set(QUEUE_FLAG_NOMERGES, disk->queue); 293 else if (nm) 294 blk_queue_flag_set(QUEUE_FLAG_NOXMERGES, disk->queue); 295 296 return ret; 297 } 298 299 static ssize_t queue_rq_affinity_show(struct gendisk *disk, char *page) 300 { 301 bool set = test_bit(QUEUE_FLAG_SAME_COMP, &disk->queue->queue_flags); 302 bool force = test_bit(QUEUE_FLAG_SAME_FORCE, &disk->queue->queue_flags); 303 304 return queue_var_show(set << force, page); 305 } 306 307 static ssize_t 308 queue_rq_affinity_store(struct gendisk *disk, const char *page, size_t count) 309 { 310 ssize_t ret = -EINVAL; 311 #ifdef CONFIG_SMP 312 struct request_queue *q = disk->queue; 313 unsigned long val; 314 315 ret = queue_var_store(&val, page, count); 316 if (ret < 0) 317 return ret; 318 319 if (val == 2) { 320 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q); 321 blk_queue_flag_set(QUEUE_FLAG_SAME_FORCE, q); 322 } else if (val == 1) { 323 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q); 324 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q); 325 } else if (val == 0) { 326 blk_queue_flag_clear(QUEUE_FLAG_SAME_COMP, q); 327 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q); 328 } 329 #endif 330 return ret; 331 } 332 333 static ssize_t queue_poll_delay_store(struct gendisk *disk, const char *page, 334 size_t count) 335 { 336 return count; 337 } 338 339 static ssize_t queue_poll_store(struct gendisk *disk, const char *page, 340 size_t count) 341 { 342 if (!(disk->queue->limits.features & BLK_FEAT_POLL)) 343 return -EINVAL; 344 pr_info_ratelimited("writes to the poll attribute are ignored.\n"); 345 pr_info_ratelimited("please use driver specific parameters instead.\n"); 346 return count; 347 } 348 349 static ssize_t queue_io_timeout_show(struct gendisk *disk, char *page) 350 { 351 return sprintf(page, "%u\n", jiffies_to_msecs(disk->queue->rq_timeout)); 352 } 353 354 static ssize_t queue_io_timeout_store(struct gendisk *disk, const char *page, 355 size_t count) 356 { 357 unsigned int val; 358 int err; 359 360 err = kstrtou32(page, 10, &val); 361 if (err || val == 0) 362 return -EINVAL; 363 364 blk_queue_rq_timeout(disk->queue, msecs_to_jiffies(val)); 365 366 return count; 367 } 368 369 static ssize_t queue_wc_show(struct gendisk *disk, char *page) 370 { 371 if (blk_queue_write_cache(disk->queue)) 372 return sprintf(page, "write back\n"); 373 return sprintf(page, "write through\n"); 374 } 375 376 static ssize_t queue_wc_store(struct gendisk *disk, const char *page, 377 size_t count) 378 { 379 struct queue_limits lim; 380 bool disable; 381 int err; 382 383 if (!strncmp(page, "write back", 10)) { 384 disable = false; 385 } else if (!strncmp(page, "write through", 13) || 386 !strncmp(page, "none", 4)) { 387 disable = true; 388 } else { 389 return -EINVAL; 390 } 391 392 lim = queue_limits_start_update(disk->queue); 393 if (disable) 394 lim.flags |= BLK_FLAG_WRITE_CACHE_DISABLED; 395 else 396 lim.flags &= ~BLK_FLAG_WRITE_CACHE_DISABLED; 397 err = queue_limits_commit_update(disk->queue, &lim); 398 if (err) 399 return err; 400 return count; 401 } 402 403 #define QUEUE_RO_ENTRY(_prefix, _name) \ 404 static struct queue_sysfs_entry _prefix##_entry = { \ 405 .attr = { .name = _name, .mode = 0444 }, \ 406 .show = _prefix##_show, \ 407 }; 408 409 #define QUEUE_RW_ENTRY(_prefix, _name) \ 410 static struct queue_sysfs_entry _prefix##_entry = { \ 411 .attr = { .name = _name, .mode = 0644 }, \ 412 .show = _prefix##_show, \ 413 .store = _prefix##_store, \ 414 }; 415 416 QUEUE_RW_ENTRY(queue_requests, "nr_requests"); 417 QUEUE_RW_ENTRY(queue_ra, "read_ahead_kb"); 418 QUEUE_RW_ENTRY(queue_max_sectors, "max_sectors_kb"); 419 QUEUE_RO_ENTRY(queue_max_hw_sectors, "max_hw_sectors_kb"); 420 QUEUE_RO_ENTRY(queue_max_segments, "max_segments"); 421 QUEUE_RO_ENTRY(queue_max_integrity_segments, "max_integrity_segments"); 422 QUEUE_RO_ENTRY(queue_max_segment_size, "max_segment_size"); 423 QUEUE_RW_ENTRY(elv_iosched, "scheduler"); 424 425 QUEUE_RO_ENTRY(queue_logical_block_size, "logical_block_size"); 426 QUEUE_RO_ENTRY(queue_physical_block_size, "physical_block_size"); 427 QUEUE_RO_ENTRY(queue_chunk_sectors, "chunk_sectors"); 428 QUEUE_RO_ENTRY(queue_io_min, "minimum_io_size"); 429 QUEUE_RO_ENTRY(queue_io_opt, "optimal_io_size"); 430 431 QUEUE_RO_ENTRY(queue_max_discard_segments, "max_discard_segments"); 432 QUEUE_RO_ENTRY(queue_discard_granularity, "discard_granularity"); 433 QUEUE_RO_ENTRY(queue_max_hw_discard_sectors, "discard_max_hw_bytes"); 434 QUEUE_RW_ENTRY(queue_max_discard_sectors, "discard_max_bytes"); 435 QUEUE_RO_ENTRY(queue_discard_zeroes_data, "discard_zeroes_data"); 436 437 QUEUE_RO_ENTRY(queue_atomic_write_max_sectors, "atomic_write_max_bytes"); 438 QUEUE_RO_ENTRY(queue_atomic_write_boundary_sectors, 439 "atomic_write_boundary_bytes"); 440 QUEUE_RO_ENTRY(queue_atomic_write_unit_max, "atomic_write_unit_max_bytes"); 441 QUEUE_RO_ENTRY(queue_atomic_write_unit_min, "atomic_write_unit_min_bytes"); 442 443 QUEUE_RO_ENTRY(queue_write_same_max, "write_same_max_bytes"); 444 QUEUE_RO_ENTRY(queue_max_write_zeroes_sectors, "write_zeroes_max_bytes"); 445 QUEUE_RO_ENTRY(queue_zone_append_max, "zone_append_max_bytes"); 446 QUEUE_RO_ENTRY(queue_zone_write_granularity, "zone_write_granularity"); 447 448 QUEUE_RO_ENTRY(queue_zoned, "zoned"); 449 QUEUE_RO_ENTRY(queue_nr_zones, "nr_zones"); 450 QUEUE_RO_ENTRY(queue_max_open_zones, "max_open_zones"); 451 QUEUE_RO_ENTRY(queue_max_active_zones, "max_active_zones"); 452 453 QUEUE_RW_ENTRY(queue_nomerges, "nomerges"); 454 QUEUE_RW_ENTRY(queue_rq_affinity, "rq_affinity"); 455 QUEUE_RW_ENTRY(queue_poll, "io_poll"); 456 QUEUE_RW_ENTRY(queue_poll_delay, "io_poll_delay"); 457 QUEUE_RW_ENTRY(queue_wc, "write_cache"); 458 QUEUE_RO_ENTRY(queue_fua, "fua"); 459 QUEUE_RO_ENTRY(queue_dax, "dax"); 460 QUEUE_RW_ENTRY(queue_io_timeout, "io_timeout"); 461 QUEUE_RO_ENTRY(queue_virt_boundary_mask, "virt_boundary_mask"); 462 QUEUE_RO_ENTRY(queue_dma_alignment, "dma_alignment"); 463 464 /* legacy alias for logical_block_size: */ 465 static struct queue_sysfs_entry queue_hw_sector_size_entry = { 466 .attr = {.name = "hw_sector_size", .mode = 0444 }, 467 .show = queue_logical_block_size_show, 468 }; 469 470 QUEUE_RW_ENTRY(queue_rotational, "rotational"); 471 QUEUE_RW_ENTRY(queue_iostats, "iostats"); 472 QUEUE_RW_ENTRY(queue_add_random, "add_random"); 473 QUEUE_RW_ENTRY(queue_stable_writes, "stable_writes"); 474 475 #ifdef CONFIG_BLK_WBT 476 static ssize_t queue_var_store64(s64 *var, const char *page) 477 { 478 int err; 479 s64 v; 480 481 err = kstrtos64(page, 10, &v); 482 if (err < 0) 483 return err; 484 485 *var = v; 486 return 0; 487 } 488 489 static ssize_t queue_wb_lat_show(struct gendisk *disk, char *page) 490 { 491 if (!wbt_rq_qos(disk->queue)) 492 return -EINVAL; 493 494 if (wbt_disabled(disk->queue)) 495 return sprintf(page, "0\n"); 496 497 return sprintf(page, "%llu\n", 498 div_u64(wbt_get_min_lat(disk->queue), 1000)); 499 } 500 501 static ssize_t queue_wb_lat_store(struct gendisk *disk, const char *page, 502 size_t count) 503 { 504 struct request_queue *q = disk->queue; 505 struct rq_qos *rqos; 506 ssize_t ret; 507 s64 val; 508 509 ret = queue_var_store64(&val, page); 510 if (ret < 0) 511 return ret; 512 if (val < -1) 513 return -EINVAL; 514 515 rqos = wbt_rq_qos(q); 516 if (!rqos) { 517 ret = wbt_init(disk); 518 if (ret) 519 return ret; 520 } 521 522 if (val == -1) 523 val = wbt_default_latency_nsec(q); 524 else if (val >= 0) 525 val *= 1000ULL; 526 527 if (wbt_get_min_lat(q) == val) 528 return count; 529 530 /* 531 * Ensure that the queue is idled, in case the latency update 532 * ends up either enabling or disabling wbt completely. We can't 533 * have IO inflight if that happens. 534 */ 535 blk_mq_quiesce_queue(q); 536 537 wbt_set_min_lat(q, val); 538 539 blk_mq_unquiesce_queue(q); 540 541 return count; 542 } 543 544 QUEUE_RW_ENTRY(queue_wb_lat, "wbt_lat_usec"); 545 #endif 546 547 /* Common attributes for bio-based and request-based queues. */ 548 static struct attribute *queue_attrs[] = { 549 &queue_ra_entry.attr, 550 &queue_max_hw_sectors_entry.attr, 551 &queue_max_sectors_entry.attr, 552 &queue_max_segments_entry.attr, 553 &queue_max_discard_segments_entry.attr, 554 &queue_max_integrity_segments_entry.attr, 555 &queue_max_segment_size_entry.attr, 556 &queue_hw_sector_size_entry.attr, 557 &queue_logical_block_size_entry.attr, 558 &queue_physical_block_size_entry.attr, 559 &queue_chunk_sectors_entry.attr, 560 &queue_io_min_entry.attr, 561 &queue_io_opt_entry.attr, 562 &queue_discard_granularity_entry.attr, 563 &queue_max_discard_sectors_entry.attr, 564 &queue_max_hw_discard_sectors_entry.attr, 565 &queue_discard_zeroes_data_entry.attr, 566 &queue_atomic_write_max_sectors_entry.attr, 567 &queue_atomic_write_boundary_sectors_entry.attr, 568 &queue_atomic_write_unit_min_entry.attr, 569 &queue_atomic_write_unit_max_entry.attr, 570 &queue_write_same_max_entry.attr, 571 &queue_max_write_zeroes_sectors_entry.attr, 572 &queue_zone_append_max_entry.attr, 573 &queue_zone_write_granularity_entry.attr, 574 &queue_rotational_entry.attr, 575 &queue_zoned_entry.attr, 576 &queue_nr_zones_entry.attr, 577 &queue_max_open_zones_entry.attr, 578 &queue_max_active_zones_entry.attr, 579 &queue_nomerges_entry.attr, 580 &queue_iostats_entry.attr, 581 &queue_stable_writes_entry.attr, 582 &queue_add_random_entry.attr, 583 &queue_poll_entry.attr, 584 &queue_wc_entry.attr, 585 &queue_fua_entry.attr, 586 &queue_dax_entry.attr, 587 &queue_poll_delay_entry.attr, 588 &queue_virt_boundary_mask_entry.attr, 589 &queue_dma_alignment_entry.attr, 590 NULL, 591 }; 592 593 /* Request-based queue attributes that are not relevant for bio-based queues. */ 594 static struct attribute *blk_mq_queue_attrs[] = { 595 &queue_requests_entry.attr, 596 &elv_iosched_entry.attr, 597 &queue_rq_affinity_entry.attr, 598 &queue_io_timeout_entry.attr, 599 #ifdef CONFIG_BLK_WBT 600 &queue_wb_lat_entry.attr, 601 #endif 602 NULL, 603 }; 604 605 static umode_t queue_attr_visible(struct kobject *kobj, struct attribute *attr, 606 int n) 607 { 608 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 609 struct request_queue *q = disk->queue; 610 611 if ((attr == &queue_max_open_zones_entry.attr || 612 attr == &queue_max_active_zones_entry.attr) && 613 !blk_queue_is_zoned(q)) 614 return 0; 615 616 return attr->mode; 617 } 618 619 static umode_t blk_mq_queue_attr_visible(struct kobject *kobj, 620 struct attribute *attr, int n) 621 { 622 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 623 struct request_queue *q = disk->queue; 624 625 if (!queue_is_mq(q)) 626 return 0; 627 628 if (attr == &queue_io_timeout_entry.attr && !q->mq_ops->timeout) 629 return 0; 630 631 return attr->mode; 632 } 633 634 static struct attribute_group queue_attr_group = { 635 .attrs = queue_attrs, 636 .is_visible = queue_attr_visible, 637 }; 638 639 static struct attribute_group blk_mq_queue_attr_group = { 640 .attrs = blk_mq_queue_attrs, 641 .is_visible = blk_mq_queue_attr_visible, 642 }; 643 644 #define to_queue(atr) container_of((atr), struct queue_sysfs_entry, attr) 645 646 static ssize_t 647 queue_attr_show(struct kobject *kobj, struct attribute *attr, char *page) 648 { 649 struct queue_sysfs_entry *entry = to_queue(attr); 650 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 651 ssize_t res; 652 653 if (!entry->show) 654 return -EIO; 655 mutex_lock(&disk->queue->sysfs_lock); 656 res = entry->show(disk, page); 657 mutex_unlock(&disk->queue->sysfs_lock); 658 return res; 659 } 660 661 static ssize_t 662 queue_attr_store(struct kobject *kobj, struct attribute *attr, 663 const char *page, size_t length) 664 { 665 struct queue_sysfs_entry *entry = to_queue(attr); 666 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 667 struct request_queue *q = disk->queue; 668 ssize_t res; 669 670 if (!entry->store) 671 return -EIO; 672 673 blk_mq_freeze_queue(q); 674 mutex_lock(&q->sysfs_lock); 675 res = entry->store(disk, page, length); 676 mutex_unlock(&q->sysfs_lock); 677 blk_mq_unfreeze_queue(q); 678 return res; 679 } 680 681 static const struct sysfs_ops queue_sysfs_ops = { 682 .show = queue_attr_show, 683 .store = queue_attr_store, 684 }; 685 686 static const struct attribute_group *blk_queue_attr_groups[] = { 687 &queue_attr_group, 688 &blk_mq_queue_attr_group, 689 NULL 690 }; 691 692 static void blk_queue_release(struct kobject *kobj) 693 { 694 /* nothing to do here, all data is associated with the parent gendisk */ 695 } 696 697 static const struct kobj_type blk_queue_ktype = { 698 .default_groups = blk_queue_attr_groups, 699 .sysfs_ops = &queue_sysfs_ops, 700 .release = blk_queue_release, 701 }; 702 703 static void blk_debugfs_remove(struct gendisk *disk) 704 { 705 struct request_queue *q = disk->queue; 706 707 mutex_lock(&q->debugfs_mutex); 708 blk_trace_shutdown(q); 709 debugfs_remove_recursive(q->debugfs_dir); 710 q->debugfs_dir = NULL; 711 q->sched_debugfs_dir = NULL; 712 q->rqos_debugfs_dir = NULL; 713 mutex_unlock(&q->debugfs_mutex); 714 } 715 716 /** 717 * blk_register_queue - register a block layer queue with sysfs 718 * @disk: Disk of which the request queue should be registered with sysfs. 719 */ 720 int blk_register_queue(struct gendisk *disk) 721 { 722 struct request_queue *q = disk->queue; 723 int ret; 724 725 mutex_lock(&q->sysfs_dir_lock); 726 kobject_init(&disk->queue_kobj, &blk_queue_ktype); 727 ret = kobject_add(&disk->queue_kobj, &disk_to_dev(disk)->kobj, "queue"); 728 if (ret < 0) 729 goto out_put_queue_kobj; 730 731 if (queue_is_mq(q)) { 732 ret = blk_mq_sysfs_register(disk); 733 if (ret) 734 goto out_put_queue_kobj; 735 } 736 mutex_lock(&q->sysfs_lock); 737 738 mutex_lock(&q->debugfs_mutex); 739 q->debugfs_dir = debugfs_create_dir(disk->disk_name, blk_debugfs_root); 740 if (queue_is_mq(q)) 741 blk_mq_debugfs_register(q); 742 mutex_unlock(&q->debugfs_mutex); 743 744 ret = disk_register_independent_access_ranges(disk); 745 if (ret) 746 goto out_debugfs_remove; 747 748 if (q->elevator) { 749 ret = elv_register_queue(q, false); 750 if (ret) 751 goto out_unregister_ia_ranges; 752 } 753 754 ret = blk_crypto_sysfs_register(disk); 755 if (ret) 756 goto out_elv_unregister; 757 758 blk_queue_flag_set(QUEUE_FLAG_REGISTERED, q); 759 wbt_enable_default(disk); 760 761 /* Now everything is ready and send out KOBJ_ADD uevent */ 762 kobject_uevent(&disk->queue_kobj, KOBJ_ADD); 763 if (q->elevator) 764 kobject_uevent(&q->elevator->kobj, KOBJ_ADD); 765 mutex_unlock(&q->sysfs_lock); 766 mutex_unlock(&q->sysfs_dir_lock); 767 768 /* 769 * SCSI probing may synchronously create and destroy a lot of 770 * request_queues for non-existent devices. Shutting down a fully 771 * functional queue takes measureable wallclock time as RCU grace 772 * periods are involved. To avoid excessive latency in these 773 * cases, a request_queue starts out in a degraded mode which is 774 * faster to shut down and is made fully functional here as 775 * request_queues for non-existent devices never get registered. 776 */ 777 if (!blk_queue_init_done(q)) { 778 blk_queue_flag_set(QUEUE_FLAG_INIT_DONE, q); 779 percpu_ref_switch_to_percpu(&q->q_usage_counter); 780 } 781 782 return ret; 783 784 out_elv_unregister: 785 elv_unregister_queue(q); 786 out_unregister_ia_ranges: 787 disk_unregister_independent_access_ranges(disk); 788 out_debugfs_remove: 789 blk_debugfs_remove(disk); 790 mutex_unlock(&q->sysfs_lock); 791 out_put_queue_kobj: 792 kobject_put(&disk->queue_kobj); 793 mutex_unlock(&q->sysfs_dir_lock); 794 return ret; 795 } 796 797 /** 798 * blk_unregister_queue - counterpart of blk_register_queue() 799 * @disk: Disk of which the request queue should be unregistered from sysfs. 800 * 801 * Note: the caller is responsible for guaranteeing that this function is called 802 * after blk_register_queue() has finished. 803 */ 804 void blk_unregister_queue(struct gendisk *disk) 805 { 806 struct request_queue *q = disk->queue; 807 808 if (WARN_ON(!q)) 809 return; 810 811 /* Return early if disk->queue was never registered. */ 812 if (!blk_queue_registered(q)) 813 return; 814 815 /* 816 * Since sysfs_remove_dir() prevents adding new directory entries 817 * before removal of existing entries starts, protect against 818 * concurrent elv_iosched_store() calls. 819 */ 820 mutex_lock(&q->sysfs_lock); 821 blk_queue_flag_clear(QUEUE_FLAG_REGISTERED, q); 822 mutex_unlock(&q->sysfs_lock); 823 824 mutex_lock(&q->sysfs_dir_lock); 825 /* 826 * Remove the sysfs attributes before unregistering the queue data 827 * structures that can be modified through sysfs. 828 */ 829 if (queue_is_mq(q)) 830 blk_mq_sysfs_unregister(disk); 831 blk_crypto_sysfs_unregister(disk); 832 833 mutex_lock(&q->sysfs_lock); 834 elv_unregister_queue(q); 835 disk_unregister_independent_access_ranges(disk); 836 mutex_unlock(&q->sysfs_lock); 837 838 /* Now that we've deleted all child objects, we can delete the queue. */ 839 kobject_uevent(&disk->queue_kobj, KOBJ_REMOVE); 840 kobject_del(&disk->queue_kobj); 841 mutex_unlock(&q->sysfs_dir_lock); 842 843 blk_debugfs_remove(disk); 844 } 845