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