block/blk-sysfs.c

   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 }