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 int (*load_module)(struct gendisk *disk, const char *page, size_t count); 27 ssize_t (*store)(struct gendisk *disk, const char *page, size_t count); 28 }; 29 30 static ssize_t 31 queue_var_show(unsigned long var, char *page) 32 { 33 return sprintf(page, "%lu\n", var); 34 } 35 36 static ssize_t 37 queue_var_store(unsigned long *var, const char *page, size_t count) 38 { 39 int err; 40 unsigned long v; 41 42 err = kstrtoul(page, 10, &v); 43 if (err || v > UINT_MAX) 44 return -EINVAL; 45 46 *var = v; 47 48 return count; 49 } 50 51 static ssize_t queue_requests_show(struct gendisk *disk, char *page) 52 { 53 return queue_var_show(disk->queue->nr_requests, page); 54 } 55 56 static ssize_t 57 queue_requests_store(struct gendisk *disk, const char *page, size_t count) 58 { 59 unsigned long nr; 60 int ret, err; 61 62 if (!queue_is_mq(disk->queue)) 63 return -EINVAL; 64 65 ret = queue_var_store(&nr, page, count); 66 if (ret < 0) 67 return ret; 68 69 if (nr < BLKDEV_MIN_RQ) 70 nr = BLKDEV_MIN_RQ; 71 72 err = blk_mq_update_nr_requests(disk->queue, nr); 73 if (err) 74 return err; 75 76 return ret; 77 } 78 79 static ssize_t queue_ra_show(struct gendisk *disk, char *page) 80 { 81 return queue_var_show(disk->bdi->ra_pages << (PAGE_SHIFT - 10), page); 82 } 83 84 static ssize_t 85 queue_ra_store(struct gendisk *disk, const char *page, size_t count) 86 { 87 unsigned long ra_kb; 88 ssize_t ret; 89 90 ret = queue_var_store(&ra_kb, page, count); 91 if (ret < 0) 92 return ret; 93 disk->bdi->ra_pages = ra_kb >> (PAGE_SHIFT - 10); 94 return ret; 95 } 96 97 #define QUEUE_SYSFS_LIMIT_SHOW(_field) \ 98 static ssize_t queue_##_field##_show(struct gendisk *disk, char *page) \ 99 { \ 100 return queue_var_show(disk->queue->limits._field, page); \ 101 } 102 103 QUEUE_SYSFS_LIMIT_SHOW(max_segments) 104 QUEUE_SYSFS_LIMIT_SHOW(max_discard_segments) 105 QUEUE_SYSFS_LIMIT_SHOW(max_integrity_segments) 106 QUEUE_SYSFS_LIMIT_SHOW(max_segment_size) 107 QUEUE_SYSFS_LIMIT_SHOW(logical_block_size) 108 QUEUE_SYSFS_LIMIT_SHOW(physical_block_size) 109 QUEUE_SYSFS_LIMIT_SHOW(chunk_sectors) 110 QUEUE_SYSFS_LIMIT_SHOW(io_min) 111 QUEUE_SYSFS_LIMIT_SHOW(io_opt) 112 QUEUE_SYSFS_LIMIT_SHOW(discard_granularity) 113 QUEUE_SYSFS_LIMIT_SHOW(zone_write_granularity) 114 QUEUE_SYSFS_LIMIT_SHOW(virt_boundary_mask) 115 QUEUE_SYSFS_LIMIT_SHOW(dma_alignment) 116 QUEUE_SYSFS_LIMIT_SHOW(max_open_zones) 117 QUEUE_SYSFS_LIMIT_SHOW(max_active_zones) 118 QUEUE_SYSFS_LIMIT_SHOW(atomic_write_unit_min) 119 QUEUE_SYSFS_LIMIT_SHOW(atomic_write_unit_max) 120 121 #define QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(_field) \ 122 static ssize_t queue_##_field##_show(struct gendisk *disk, char *page) \ 123 { \ 124 return sprintf(page, "%llu\n", \ 125 (unsigned long long)disk->queue->limits._field << \ 126 SECTOR_SHIFT); \ 127 } 128 129 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(max_discard_sectors) 130 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(max_hw_discard_sectors) 131 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(max_write_zeroes_sectors) 132 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(atomic_write_max_sectors) 133 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(atomic_write_boundary_sectors) 134 135 #define QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_KB(_field) \ 136 static ssize_t queue_##_field##_show(struct gendisk *disk, char *page) \ 137 { \ 138 return queue_var_show(disk->queue->limits._field >> 1, page); \ 139 } 140 141 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_KB(max_sectors) 142 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_KB(max_hw_sectors) 143 144 #define QUEUE_SYSFS_SHOW_CONST(_name, _val) \ 145 static ssize_t queue_##_name##_show(struct gendisk *disk, char *page) \ 146 { \ 147 return sprintf(page, "%d\n", _val); \ 148 } 149 150 /* deprecated fields */ 151 QUEUE_SYSFS_SHOW_CONST(discard_zeroes_data, 0) 152 QUEUE_SYSFS_SHOW_CONST(write_same_max, 0) 153 QUEUE_SYSFS_SHOW_CONST(poll_delay, -1) 154 155 static ssize_t queue_max_discard_sectors_store(struct gendisk *disk, 156 const char *page, size_t count) 157 { 158 unsigned long max_discard_bytes; 159 struct queue_limits lim; 160 ssize_t ret; 161 int err; 162 163 ret = queue_var_store(&max_discard_bytes, page, count); 164 if (ret < 0) 165 return ret; 166 167 if (max_discard_bytes & (disk->queue->limits.discard_granularity - 1)) 168 return -EINVAL; 169 170 if ((max_discard_bytes >> SECTOR_SHIFT) > UINT_MAX) 171 return -EINVAL; 172 173 lim = queue_limits_start_update(disk->queue); 174 lim.max_user_discard_sectors = max_discard_bytes >> SECTOR_SHIFT; 175 err = queue_limits_commit_update(disk->queue, &lim); 176 if (err) 177 return err; 178 return ret; 179 } 180 181 /* 182 * For zone append queue_max_zone_append_sectors does not just return the 183 * underlying queue limits, but actually contains a calculation. Because of 184 * that we can't simply use QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES here. 185 */ 186 static ssize_t queue_zone_append_max_show(struct gendisk *disk, char *page) 187 { 188 return sprintf(page, "%llu\n", 189 (u64)queue_max_zone_append_sectors(disk->queue) << 190 SECTOR_SHIFT); 191 } 192 193 static ssize_t 194 queue_max_sectors_store(struct gendisk *disk, const char *page, size_t count) 195 { 196 unsigned long max_sectors_kb; 197 struct queue_limits lim; 198 ssize_t ret; 199 int err; 200 201 ret = queue_var_store(&max_sectors_kb, page, count); 202 if (ret < 0) 203 return ret; 204 205 lim = queue_limits_start_update(disk->queue); 206 lim.max_user_sectors = max_sectors_kb << 1; 207 err = queue_limits_commit_update(disk->queue, &lim); 208 if (err) 209 return err; 210 return ret; 211 } 212 213 static ssize_t queue_feature_store(struct gendisk *disk, const char *page, 214 size_t count, blk_features_t feature) 215 { 216 struct queue_limits lim; 217 unsigned long val; 218 ssize_t ret; 219 220 ret = queue_var_store(&val, page, count); 221 if (ret < 0) 222 return ret; 223 224 lim = queue_limits_start_update(disk->queue); 225 if (val) 226 lim.features |= feature; 227 else 228 lim.features &= ~feature; 229 ret = queue_limits_commit_update(disk->queue, &lim); 230 if (ret) 231 return ret; 232 return count; 233 } 234 235 #define QUEUE_SYSFS_FEATURE(_name, _feature) \ 236 static ssize_t queue_##_name##_show(struct gendisk *disk, char *page) \ 237 { \ 238 return sprintf(page, "%u\n", \ 239 !!(disk->queue->limits.features & _feature)); \ 240 } \ 241 static ssize_t queue_##_name##_store(struct gendisk *disk, \ 242 const char *page, size_t count) \ 243 { \ 244 return queue_feature_store(disk, page, count, _feature); \ 245 } 246 247 QUEUE_SYSFS_FEATURE(rotational, BLK_FEAT_ROTATIONAL) 248 QUEUE_SYSFS_FEATURE(add_random, BLK_FEAT_ADD_RANDOM) 249 QUEUE_SYSFS_FEATURE(iostats, BLK_FEAT_IO_STAT) 250 QUEUE_SYSFS_FEATURE(stable_writes, BLK_FEAT_STABLE_WRITES); 251 252 #define QUEUE_SYSFS_FEATURE_SHOW(_name, _feature) \ 253 static ssize_t queue_##_name##_show(struct gendisk *disk, char *page) \ 254 { \ 255 return sprintf(page, "%u\n", \ 256 !!(disk->queue->limits.features & _feature)); \ 257 } 258 259 QUEUE_SYSFS_FEATURE_SHOW(poll, BLK_FEAT_POLL); 260 QUEUE_SYSFS_FEATURE_SHOW(fua, BLK_FEAT_FUA); 261 QUEUE_SYSFS_FEATURE_SHOW(dax, BLK_FEAT_DAX); 262 263 static ssize_t queue_zoned_show(struct gendisk *disk, char *page) 264 { 265 if (blk_queue_is_zoned(disk->queue)) 266 return sprintf(page, "host-managed\n"); 267 return sprintf(page, "none\n"); 268 } 269 270 static ssize_t queue_nr_zones_show(struct gendisk *disk, char *page) 271 { 272 return queue_var_show(disk_nr_zones(disk), page); 273 } 274 275 static ssize_t queue_nomerges_show(struct gendisk *disk, char *page) 276 { 277 return queue_var_show((blk_queue_nomerges(disk->queue) << 1) | 278 blk_queue_noxmerges(disk->queue), page); 279 } 280 281 static ssize_t queue_nomerges_store(struct gendisk *disk, const char *page, 282 size_t count) 283 { 284 unsigned long nm; 285 ssize_t ret = queue_var_store(&nm, page, count); 286 287 if (ret < 0) 288 return ret; 289 290 blk_queue_flag_clear(QUEUE_FLAG_NOMERGES, disk->queue); 291 blk_queue_flag_clear(QUEUE_FLAG_NOXMERGES, disk->queue); 292 if (nm == 2) 293 blk_queue_flag_set(QUEUE_FLAG_NOMERGES, disk->queue); 294 else if (nm) 295 blk_queue_flag_set(QUEUE_FLAG_NOXMERGES, disk->queue); 296 297 return ret; 298 } 299 300 static ssize_t queue_rq_affinity_show(struct gendisk *disk, char *page) 301 { 302 bool set = test_bit(QUEUE_FLAG_SAME_COMP, &disk->queue->queue_flags); 303 bool force = test_bit(QUEUE_FLAG_SAME_FORCE, &disk->queue->queue_flags); 304 305 return queue_var_show(set << force, page); 306 } 307 308 static ssize_t 309 queue_rq_affinity_store(struct gendisk *disk, const char *page, size_t count) 310 { 311 ssize_t ret = -EINVAL; 312 #ifdef CONFIG_SMP 313 struct request_queue *q = disk->queue; 314 unsigned long val; 315 316 ret = queue_var_store(&val, page, count); 317 if (ret < 0) 318 return ret; 319 320 if (val == 2) { 321 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q); 322 blk_queue_flag_set(QUEUE_FLAG_SAME_FORCE, q); 323 } else if (val == 1) { 324 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q); 325 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q); 326 } else if (val == 0) { 327 blk_queue_flag_clear(QUEUE_FLAG_SAME_COMP, q); 328 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q); 329 } 330 #endif 331 return ret; 332 } 333 334 static ssize_t queue_poll_delay_store(struct gendisk *disk, const char *page, 335 size_t count) 336 { 337 return count; 338 } 339 340 static ssize_t queue_poll_store(struct gendisk *disk, const char *page, 341 size_t count) 342 { 343 if (!(disk->queue->limits.features & BLK_FEAT_POLL)) 344 return -EINVAL; 345 pr_info_ratelimited("writes to the poll attribute are ignored.\n"); 346 pr_info_ratelimited("please use driver specific parameters instead.\n"); 347 return count; 348 } 349 350 static ssize_t queue_io_timeout_show(struct gendisk *disk, char *page) 351 { 352 return sprintf(page, "%u\n", jiffies_to_msecs(disk->queue->rq_timeout)); 353 } 354 355 static ssize_t queue_io_timeout_store(struct gendisk *disk, const char *page, 356 size_t count) 357 { 358 unsigned int val; 359 int err; 360 361 err = kstrtou32(page, 10, &val); 362 if (err || val == 0) 363 return -EINVAL; 364 365 blk_queue_rq_timeout(disk->queue, msecs_to_jiffies(val)); 366 367 return count; 368 } 369 370 static ssize_t queue_wc_show(struct gendisk *disk, char *page) 371 { 372 if (blk_queue_write_cache(disk->queue)) 373 return sprintf(page, "write back\n"); 374 return sprintf(page, "write through\n"); 375 } 376 377 static ssize_t queue_wc_store(struct gendisk *disk, const char *page, 378 size_t count) 379 { 380 struct queue_limits lim; 381 bool disable; 382 int err; 383 384 if (!strncmp(page, "write back", 10)) { 385 disable = false; 386 } else if (!strncmp(page, "write through", 13) || 387 !strncmp(page, "none", 4)) { 388 disable = true; 389 } else { 390 return -EINVAL; 391 } 392 393 lim = queue_limits_start_update(disk->queue); 394 if (disable) 395 lim.flags |= BLK_FLAG_WRITE_CACHE_DISABLED; 396 else 397 lim.flags &= ~BLK_FLAG_WRITE_CACHE_DISABLED; 398 err = queue_limits_commit_update(disk->queue, &lim); 399 if (err) 400 return err; 401 return count; 402 } 403 404 #define QUEUE_RO_ENTRY(_prefix, _name) \ 405 static struct queue_sysfs_entry _prefix##_entry = { \ 406 .attr = { .name = _name, .mode = 0444 }, \ 407 .show = _prefix##_show, \ 408 }; 409 410 #define QUEUE_RW_ENTRY(_prefix, _name) \ 411 static struct queue_sysfs_entry _prefix##_entry = { \ 412 .attr = { .name = _name, .mode = 0644 }, \ 413 .show = _prefix##_show, \ 414 .store = _prefix##_store, \ 415 }; 416 417 #define QUEUE_RW_LOAD_MODULE_ENTRY(_prefix, _name) \ 418 static struct queue_sysfs_entry _prefix##_entry = { \ 419 .attr = { .name = _name, .mode = 0644 }, \ 420 .show = _prefix##_show, \ 421 .load_module = _prefix##_load_module, \ 422 .store = _prefix##_store, \ 423 } 424 425 QUEUE_RW_ENTRY(queue_requests, "nr_requests"); 426 QUEUE_RW_ENTRY(queue_ra, "read_ahead_kb"); 427 QUEUE_RW_ENTRY(queue_max_sectors, "max_sectors_kb"); 428 QUEUE_RO_ENTRY(queue_max_hw_sectors, "max_hw_sectors_kb"); 429 QUEUE_RO_ENTRY(queue_max_segments, "max_segments"); 430 QUEUE_RO_ENTRY(queue_max_integrity_segments, "max_integrity_segments"); 431 QUEUE_RO_ENTRY(queue_max_segment_size, "max_segment_size"); 432 QUEUE_RW_LOAD_MODULE_ENTRY(elv_iosched, "scheduler"); 433 434 QUEUE_RO_ENTRY(queue_logical_block_size, "logical_block_size"); 435 QUEUE_RO_ENTRY(queue_physical_block_size, "physical_block_size"); 436 QUEUE_RO_ENTRY(queue_chunk_sectors, "chunk_sectors"); 437 QUEUE_RO_ENTRY(queue_io_min, "minimum_io_size"); 438 QUEUE_RO_ENTRY(queue_io_opt, "optimal_io_size"); 439 440 QUEUE_RO_ENTRY(queue_max_discard_segments, "max_discard_segments"); 441 QUEUE_RO_ENTRY(queue_discard_granularity, "discard_granularity"); 442 QUEUE_RO_ENTRY(queue_max_hw_discard_sectors, "discard_max_hw_bytes"); 443 QUEUE_RW_ENTRY(queue_max_discard_sectors, "discard_max_bytes"); 444 QUEUE_RO_ENTRY(queue_discard_zeroes_data, "discard_zeroes_data"); 445 446 QUEUE_RO_ENTRY(queue_atomic_write_max_sectors, "atomic_write_max_bytes"); 447 QUEUE_RO_ENTRY(queue_atomic_write_boundary_sectors, 448 "atomic_write_boundary_bytes"); 449 QUEUE_RO_ENTRY(queue_atomic_write_unit_max, "atomic_write_unit_max_bytes"); 450 QUEUE_RO_ENTRY(queue_atomic_write_unit_min, "atomic_write_unit_min_bytes"); 451 452 QUEUE_RO_ENTRY(queue_write_same_max, "write_same_max_bytes"); 453 QUEUE_RO_ENTRY(queue_max_write_zeroes_sectors, "write_zeroes_max_bytes"); 454 QUEUE_RO_ENTRY(queue_zone_append_max, "zone_append_max_bytes"); 455 QUEUE_RO_ENTRY(queue_zone_write_granularity, "zone_write_granularity"); 456 457 QUEUE_RO_ENTRY(queue_zoned, "zoned"); 458 QUEUE_RO_ENTRY(queue_nr_zones, "nr_zones"); 459 QUEUE_RO_ENTRY(queue_max_open_zones, "max_open_zones"); 460 QUEUE_RO_ENTRY(queue_max_active_zones, "max_active_zones"); 461 462 QUEUE_RW_ENTRY(queue_nomerges, "nomerges"); 463 QUEUE_RW_ENTRY(queue_rq_affinity, "rq_affinity"); 464 QUEUE_RW_ENTRY(queue_poll, "io_poll"); 465 QUEUE_RW_ENTRY(queue_poll_delay, "io_poll_delay"); 466 QUEUE_RW_ENTRY(queue_wc, "write_cache"); 467 QUEUE_RO_ENTRY(queue_fua, "fua"); 468 QUEUE_RO_ENTRY(queue_dax, "dax"); 469 QUEUE_RW_ENTRY(queue_io_timeout, "io_timeout"); 470 QUEUE_RO_ENTRY(queue_virt_boundary_mask, "virt_boundary_mask"); 471 QUEUE_RO_ENTRY(queue_dma_alignment, "dma_alignment"); 472 473 /* legacy alias for logical_block_size: */ 474 static struct queue_sysfs_entry queue_hw_sector_size_entry = { 475 .attr = {.name = "hw_sector_size", .mode = 0444 }, 476 .show = queue_logical_block_size_show, 477 }; 478 479 QUEUE_RW_ENTRY(queue_rotational, "rotational"); 480 QUEUE_RW_ENTRY(queue_iostats, "iostats"); 481 QUEUE_RW_ENTRY(queue_add_random, "add_random"); 482 QUEUE_RW_ENTRY(queue_stable_writes, "stable_writes"); 483 484 #ifdef CONFIG_BLK_WBT 485 static ssize_t queue_var_store64(s64 *var, const char *page) 486 { 487 int err; 488 s64 v; 489 490 err = kstrtos64(page, 10, &v); 491 if (err < 0) 492 return err; 493 494 *var = v; 495 return 0; 496 } 497 498 static ssize_t queue_wb_lat_show(struct gendisk *disk, char *page) 499 { 500 if (!wbt_rq_qos(disk->queue)) 501 return -EINVAL; 502 503 if (wbt_disabled(disk->queue)) 504 return sprintf(page, "0\n"); 505 506 return sprintf(page, "%llu\n", 507 div_u64(wbt_get_min_lat(disk->queue), 1000)); 508 } 509 510 static ssize_t queue_wb_lat_store(struct gendisk *disk, const char *page, 511 size_t count) 512 { 513 struct request_queue *q = disk->queue; 514 struct rq_qos *rqos; 515 ssize_t ret; 516 s64 val; 517 518 ret = queue_var_store64(&val, page); 519 if (ret < 0) 520 return ret; 521 if (val < -1) 522 return -EINVAL; 523 524 rqos = wbt_rq_qos(q); 525 if (!rqos) { 526 ret = wbt_init(disk); 527 if (ret) 528 return ret; 529 } 530 531 if (val == -1) 532 val = wbt_default_latency_nsec(q); 533 else if (val >= 0) 534 val *= 1000ULL; 535 536 if (wbt_get_min_lat(q) == val) 537 return count; 538 539 /* 540 * Ensure that the queue is idled, in case the latency update 541 * ends up either enabling or disabling wbt completely. We can't 542 * have IO inflight if that happens. 543 */ 544 blk_mq_quiesce_queue(q); 545 546 wbt_set_min_lat(q, val); 547 548 blk_mq_unquiesce_queue(q); 549 550 return count; 551 } 552 553 QUEUE_RW_ENTRY(queue_wb_lat, "wbt_lat_usec"); 554 #endif 555 556 /* Common attributes for bio-based and request-based queues. */ 557 static struct attribute *queue_attrs[] = { 558 &queue_ra_entry.attr, 559 &queue_max_hw_sectors_entry.attr, 560 &queue_max_sectors_entry.attr, 561 &queue_max_segments_entry.attr, 562 &queue_max_discard_segments_entry.attr, 563 &queue_max_integrity_segments_entry.attr, 564 &queue_max_segment_size_entry.attr, 565 &queue_hw_sector_size_entry.attr, 566 &queue_logical_block_size_entry.attr, 567 &queue_physical_block_size_entry.attr, 568 &queue_chunk_sectors_entry.attr, 569 &queue_io_min_entry.attr, 570 &queue_io_opt_entry.attr, 571 &queue_discard_granularity_entry.attr, 572 &queue_max_discard_sectors_entry.attr, 573 &queue_max_hw_discard_sectors_entry.attr, 574 &queue_discard_zeroes_data_entry.attr, 575 &queue_atomic_write_max_sectors_entry.attr, 576 &queue_atomic_write_boundary_sectors_entry.attr, 577 &queue_atomic_write_unit_min_entry.attr, 578 &queue_atomic_write_unit_max_entry.attr, 579 &queue_write_same_max_entry.attr, 580 &queue_max_write_zeroes_sectors_entry.attr, 581 &queue_zone_append_max_entry.attr, 582 &queue_zone_write_granularity_entry.attr, 583 &queue_rotational_entry.attr, 584 &queue_zoned_entry.attr, 585 &queue_nr_zones_entry.attr, 586 &queue_max_open_zones_entry.attr, 587 &queue_max_active_zones_entry.attr, 588 &queue_nomerges_entry.attr, 589 &queue_iostats_entry.attr, 590 &queue_stable_writes_entry.attr, 591 &queue_add_random_entry.attr, 592 &queue_poll_entry.attr, 593 &queue_wc_entry.attr, 594 &queue_fua_entry.attr, 595 &queue_dax_entry.attr, 596 &queue_poll_delay_entry.attr, 597 &queue_virt_boundary_mask_entry.attr, 598 &queue_dma_alignment_entry.attr, 599 NULL, 600 }; 601 602 /* Request-based queue attributes that are not relevant for bio-based queues. */ 603 static struct attribute *blk_mq_queue_attrs[] = { 604 &queue_requests_entry.attr, 605 &elv_iosched_entry.attr, 606 &queue_rq_affinity_entry.attr, 607 &queue_io_timeout_entry.attr, 608 #ifdef CONFIG_BLK_WBT 609 &queue_wb_lat_entry.attr, 610 #endif 611 NULL, 612 }; 613 614 static umode_t queue_attr_visible(struct kobject *kobj, struct attribute *attr, 615 int n) 616 { 617 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 618 struct request_queue *q = disk->queue; 619 620 if ((attr == &queue_max_open_zones_entry.attr || 621 attr == &queue_max_active_zones_entry.attr) && 622 !blk_queue_is_zoned(q)) 623 return 0; 624 625 return attr->mode; 626 } 627 628 static umode_t blk_mq_queue_attr_visible(struct kobject *kobj, 629 struct attribute *attr, int n) 630 { 631 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 632 struct request_queue *q = disk->queue; 633 634 if (!queue_is_mq(q)) 635 return 0; 636 637 if (attr == &queue_io_timeout_entry.attr && !q->mq_ops->timeout) 638 return 0; 639 640 return attr->mode; 641 } 642 643 static struct attribute_group queue_attr_group = { 644 .attrs = queue_attrs, 645 .is_visible = queue_attr_visible, 646 }; 647 648 static struct attribute_group blk_mq_queue_attr_group = { 649 .attrs = blk_mq_queue_attrs, 650 .is_visible = blk_mq_queue_attr_visible, 651 }; 652 653 #define to_queue(atr) container_of((atr), struct queue_sysfs_entry, attr) 654 655 static ssize_t 656 queue_attr_show(struct kobject *kobj, struct attribute *attr, char *page) 657 { 658 struct queue_sysfs_entry *entry = to_queue(attr); 659 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 660 ssize_t res; 661 662 if (!entry->show) 663 return -EIO; 664 mutex_lock(&disk->queue->sysfs_lock); 665 res = entry->show(disk, page); 666 mutex_unlock(&disk->queue->sysfs_lock); 667 return res; 668 } 669 670 static ssize_t 671 queue_attr_store(struct kobject *kobj, struct attribute *attr, 672 const char *page, size_t length) 673 { 674 struct queue_sysfs_entry *entry = to_queue(attr); 675 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 676 struct request_queue *q = disk->queue; 677 ssize_t res; 678 679 if (!entry->store) 680 return -EIO; 681 682 /* 683 * If the attribute needs to load a module, do it before freezing the 684 * queue to ensure that the module file can be read when the request 685 * queue is the one for the device storing the module file. 686 */ 687 if (entry->load_module) { 688 res = entry->load_module(disk, page, length); 689 if (res) 690 return res; 691 } 692 693 blk_mq_freeze_queue(q); 694 mutex_lock(&q->sysfs_lock); 695 res = entry->store(disk, page, length); 696 mutex_unlock(&q->sysfs_lock); 697 blk_mq_unfreeze_queue(q); 698 return res; 699 } 700 701 static const struct sysfs_ops queue_sysfs_ops = { 702 .show = queue_attr_show, 703 .store = queue_attr_store, 704 }; 705 706 static const struct attribute_group *blk_queue_attr_groups[] = { 707 &queue_attr_group, 708 &blk_mq_queue_attr_group, 709 NULL 710 }; 711 712 static void blk_queue_release(struct kobject *kobj) 713 { 714 /* nothing to do here, all data is associated with the parent gendisk */ 715 } 716 717 static const struct kobj_type blk_queue_ktype = { 718 .default_groups = blk_queue_attr_groups, 719 .sysfs_ops = &queue_sysfs_ops, 720 .release = blk_queue_release, 721 }; 722 723 static void blk_debugfs_remove(struct gendisk *disk) 724 { 725 struct request_queue *q = disk->queue; 726 727 mutex_lock(&q->debugfs_mutex); 728 blk_trace_shutdown(q); 729 debugfs_remove_recursive(q->debugfs_dir); 730 q->debugfs_dir = NULL; 731 q->sched_debugfs_dir = NULL; 732 q->rqos_debugfs_dir = NULL; 733 mutex_unlock(&q->debugfs_mutex); 734 } 735 736 /** 737 * blk_register_queue - register a block layer queue with sysfs 738 * @disk: Disk of which the request queue should be registered with sysfs. 739 */ 740 int blk_register_queue(struct gendisk *disk) 741 { 742 struct request_queue *q = disk->queue; 743 int ret; 744 745 mutex_lock(&q->sysfs_dir_lock); 746 kobject_init(&disk->queue_kobj, &blk_queue_ktype); 747 ret = kobject_add(&disk->queue_kobj, &disk_to_dev(disk)->kobj, "queue"); 748 if (ret < 0) 749 goto out_put_queue_kobj; 750 751 if (queue_is_mq(q)) { 752 ret = blk_mq_sysfs_register(disk); 753 if (ret) 754 goto out_put_queue_kobj; 755 } 756 mutex_lock(&q->sysfs_lock); 757 758 mutex_lock(&q->debugfs_mutex); 759 q->debugfs_dir = debugfs_create_dir(disk->disk_name, blk_debugfs_root); 760 if (queue_is_mq(q)) 761 blk_mq_debugfs_register(q); 762 mutex_unlock(&q->debugfs_mutex); 763 764 ret = disk_register_independent_access_ranges(disk); 765 if (ret) 766 goto out_debugfs_remove; 767 768 if (q->elevator) { 769 ret = elv_register_queue(q, false); 770 if (ret) 771 goto out_unregister_ia_ranges; 772 } 773 774 ret = blk_crypto_sysfs_register(disk); 775 if (ret) 776 goto out_elv_unregister; 777 778 blk_queue_flag_set(QUEUE_FLAG_REGISTERED, q); 779 wbt_enable_default(disk); 780 781 /* Now everything is ready and send out KOBJ_ADD uevent */ 782 kobject_uevent(&disk->queue_kobj, KOBJ_ADD); 783 if (q->elevator) 784 kobject_uevent(&q->elevator->kobj, KOBJ_ADD); 785 mutex_unlock(&q->sysfs_lock); 786 mutex_unlock(&q->sysfs_dir_lock); 787 788 /* 789 * SCSI probing may synchronously create and destroy a lot of 790 * request_queues for non-existent devices. Shutting down a fully 791 * functional queue takes measureable wallclock time as RCU grace 792 * periods are involved. To avoid excessive latency in these 793 * cases, a request_queue starts out in a degraded mode which is 794 * faster to shut down and is made fully functional here as 795 * request_queues for non-existent devices never get registered. 796 */ 797 if (!blk_queue_init_done(q)) { 798 blk_queue_flag_set(QUEUE_FLAG_INIT_DONE, q); 799 percpu_ref_switch_to_percpu(&q->q_usage_counter); 800 } 801 802 return ret; 803 804 out_elv_unregister: 805 elv_unregister_queue(q); 806 out_unregister_ia_ranges: 807 disk_unregister_independent_access_ranges(disk); 808 out_debugfs_remove: 809 blk_debugfs_remove(disk); 810 mutex_unlock(&q->sysfs_lock); 811 out_put_queue_kobj: 812 kobject_put(&disk->queue_kobj); 813 mutex_unlock(&q->sysfs_dir_lock); 814 return ret; 815 } 816 817 /** 818 * blk_unregister_queue - counterpart of blk_register_queue() 819 * @disk: Disk of which the request queue should be unregistered from sysfs. 820 * 821 * Note: the caller is responsible for guaranteeing that this function is called 822 * after blk_register_queue() has finished. 823 */ 824 void blk_unregister_queue(struct gendisk *disk) 825 { 826 struct request_queue *q = disk->queue; 827 828 if (WARN_ON(!q)) 829 return; 830 831 /* Return early if disk->queue was never registered. */ 832 if (!blk_queue_registered(q)) 833 return; 834 835 /* 836 * Since sysfs_remove_dir() prevents adding new directory entries 837 * before removal of existing entries starts, protect against 838 * concurrent elv_iosched_store() calls. 839 */ 840 mutex_lock(&q->sysfs_lock); 841 blk_queue_flag_clear(QUEUE_FLAG_REGISTERED, q); 842 mutex_unlock(&q->sysfs_lock); 843 844 mutex_lock(&q->sysfs_dir_lock); 845 /* 846 * Remove the sysfs attributes before unregistering the queue data 847 * structures that can be modified through sysfs. 848 */ 849 if (queue_is_mq(q)) 850 blk_mq_sysfs_unregister(disk); 851 blk_crypto_sysfs_unregister(disk); 852 853 mutex_lock(&q->sysfs_lock); 854 elv_unregister_queue(q); 855 disk_unregister_independent_access_ranges(disk); 856 mutex_unlock(&q->sysfs_lock); 857 858 /* Now that we've deleted all child objects, we can delete the queue. */ 859 kobject_uevent(&disk->queue_kobj, KOBJ_REMOVE); 860 kobject_del(&disk->queue_kobj); 861 mutex_unlock(&q->sysfs_dir_lock); 862 863 blk_debugfs_remove(disk); 864 } 865