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/blk-mq.h>
  13 #include <linux/debugfs.h>
  14
  15 #include "blk.h"
  16 #include "blk-mq.h"
  17 #include "blk-mq-debugfs.h"
  18 #include "blk-mq-sched.h"
  19 #include "blk-rq-qos.h"
  20 #include "blk-wbt.h"
  21 #include "blk-cgroup.h"
  22 #include "blk-throttle.h"
  23
  24 struct queue_sysfs_entry {
  25         struct attribute attr;
  26         ssize_t (*show)(struct request_queue *, char *);
  27         ssize_t (*store)(struct request_queue *, const char *, size_t);
  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_var_store64(s64 *var, const char *page)
  52 {
  53         int err;
  54         s64 v;
  55
  56         err = kstrtos64(page, 10, &v);
  57         if (err < 0)
  58                 return err;
  59
  60         *var = v;
  61         return 0;
  62 }
  63
  64 static ssize_t queue_requests_show(struct request_queue *q, char *page)
  65 {
  66         return queue_var_show(q->nr_requests, page);
  67 }
  68
  69 static ssize_t
  70 queue_requests_store(struct request_queue *q, const char *page, size_t count)
  71 {
  72         unsigned long nr;
  73         int ret, err;
  74
  75         if (!queue_is_mq(q))
  76                 return -EINVAL;
  77
  78         ret = queue_var_store(&nr, page, count);
  79         if (ret < 0)
  80                 return ret;
  81
  82         if (nr < BLKDEV_MIN_RQ)
  83                 nr = BLKDEV_MIN_RQ;
  84
  85         err = blk_mq_update_nr_requests(q, nr);
  86         if (err)
  87                 return err;
  88
  89         return ret;
  90 }
  91
  92 static ssize_t queue_ra_show(struct request_queue *q, char *page)
  93 {
  94         unsigned long ra_kb;
  95
  96         if (!q->disk)
  97                 return -EINVAL;
  98         ra_kb = q->disk->bdi->ra_pages << (PAGE_SHIFT - 10);
  99         return queue_var_show(ra_kb, page);
 100 }
 101
 102 static ssize_t
 103 queue_ra_store(struct request_queue *q, const char *page, size_t count)
 104 {
 105         unsigned long ra_kb;
 106         ssize_t ret;
 107
 108         if (!q->disk)
 109                 return -EINVAL;
 110         ret = queue_var_store(&ra_kb, page, count);
 111         if (ret < 0)
 112                 return ret;
 113         q->disk->bdi->ra_pages = ra_kb >> (PAGE_SHIFT - 10);
 114         return ret;
 115 }
 116
 117 static ssize_t queue_max_sectors_show(struct request_queue *q, char *page)
 118 {
 119         int max_sectors_kb = queue_max_sectors(q) >> 1;
 120
 121         return queue_var_show(max_sectors_kb, page);
 122 }
 123
 124 static ssize_t queue_max_segments_show(struct request_queue *q, char *page)
 125 {
 126         return queue_var_show(queue_max_segments(q), page);
 127 }
 128
 129 static ssize_t queue_max_discard_segments_show(struct request_queue *q,
 130                 char *page)
 131 {
 132         return queue_var_show(queue_max_discard_segments(q), page);
 133 }
 134
 135 static ssize_t queue_max_integrity_segments_show(struct request_queue *q, char *page)
 136 {
 137         return queue_var_show(q->limits.max_integrity_segments, page);
 138 }
 139
 140 static ssize_t queue_max_segment_size_show(struct request_queue *q, char *page)
 141 {
 142         return queue_var_show(queue_max_segment_size(q), page);
 143 }
 144
 145 static ssize_t queue_logical_block_size_show(struct request_queue *q, char *page)
 146 {
 147         return queue_var_show(queue_logical_block_size(q), page);
 148 }
 149
 150 static ssize_t queue_physical_block_size_show(struct request_queue *q, char *page)
 151 {
 152         return queue_var_show(queue_physical_block_size(q), page);
 153 }
 154
 155 static ssize_t queue_chunk_sectors_show(struct request_queue *q, char *page)
 156 {
 157         return queue_var_show(q->limits.chunk_sectors, page);
 158 }
 159
 160 static ssize_t queue_io_min_show(struct request_queue *q, char *page)
 161 {
 162         return queue_var_show(queue_io_min(q), page);
 163 }
 164
 165 static ssize_t queue_io_opt_show(struct request_queue *q, char *page)
 166 {
 167         return queue_var_show(queue_io_opt(q), page);
 168 }
 169
 170 static ssize_t queue_discard_granularity_show(struct request_queue *q, char *page)
 171 {
 172         return queue_var_show(q->limits.discard_granularity, page);
 173 }
 174
 175 static ssize_t queue_discard_max_hw_show(struct request_queue *q, char *page)
 176 {
 177
 178         return sprintf(page, "%llu\n",
 179                 (unsigned long long)q->limits.max_hw_discard_sectors << 9);
 180 }
 181
 182 static ssize_t queue_discard_max_show(struct request_queue *q, char *page)
 183 {
 184         return sprintf(page, "%llu\n",
 185                        (unsigned long long)q->limits.max_discard_sectors << 9);
 186 }
 187
 188 static ssize_t queue_discard_max_store(struct request_queue *q,
 189                                        const char *page, size_t count)
 190 {
 191         unsigned long max_discard;
 192         ssize_t ret = queue_var_store(&max_discard, page, count);
 193
 194         if (ret < 0)
 195                 return ret;
 196
 197         if (max_discard & (q->limits.discard_granularity - 1))
 198                 return -EINVAL;
 199
 200         max_discard >>= 9;
 201         if (max_discard > UINT_MAX)
 202                 return -EINVAL;
 203
 204         if (max_discard > q->limits.max_hw_discard_sectors)
 205                 max_discard = q->limits.max_hw_discard_sectors;
 206
 207         q->limits.max_discard_sectors = max_discard;
 208         return ret;
 209 }
 210
 211 static ssize_t queue_discard_zeroes_data_show(struct request_queue *q, char *page)
 212 {
 213         return queue_var_show(0, page);
 214 }
 215
 216 static ssize_t queue_write_same_max_show(struct request_queue *q, char *page)
 217 {
 218         return queue_var_show(0, page);
 219 }
 220
 221 static ssize_t queue_write_zeroes_max_show(struct request_queue *q, char *page)
 222 {
 223         return sprintf(page, "%llu\n",
 224                 (unsigned long long)q->limits.max_write_zeroes_sectors << 9);
 225 }
 226
 227 static ssize_t queue_zone_write_granularity_show(struct request_queue *q,
 228                                                  char *page)
 229 {
 230         return queue_var_show(queue_zone_write_granularity(q), page);
 231 }
 232
 233 static ssize_t queue_zone_append_max_show(struct request_queue *q, char *page)
 234 {
 235         unsigned long long max_sectors = q->limits.max_zone_append_sectors;
 236
 237         return sprintf(page, "%llu\n", max_sectors << SECTOR_SHIFT);
 238 }
 239
 240 static ssize_t
 241 queue_max_sectors_store(struct request_queue *q, const char *page, size_t count)
 242 {
 243         unsigned long var;
 244         unsigned int max_sectors_kb,
 245                 max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1,
 246                         page_kb = 1 << (PAGE_SHIFT - 10);
 247         ssize_t ret = queue_var_store(&var, page, count);
 248
 249         if (ret < 0)
 250                 return ret;
 251
 252         max_sectors_kb = (unsigned int)var;
 253         max_hw_sectors_kb = min_not_zero(max_hw_sectors_kb,
 254                                          q->limits.max_dev_sectors >> 1);
 255         if (max_sectors_kb == 0) {
 256                 q->limits.max_user_sectors = 0;
 257                 max_sectors_kb = min(max_hw_sectors_kb,
 258                                      BLK_DEF_MAX_SECTORS >> 1);
 259         } else {
 260                 if (max_sectors_kb > max_hw_sectors_kb ||
 261                     max_sectors_kb < page_kb)
 262                         return -EINVAL;
 263                 q->limits.max_user_sectors = max_sectors_kb << 1;
 264         }
 265
 266         spin_lock_irq(&q->queue_lock);
 267         q->limits.max_sectors = max_sectors_kb << 1;
 268         if (q->disk)
 269                 q->disk->bdi->io_pages = max_sectors_kb >> (PAGE_SHIFT - 10);
 270         spin_unlock_irq(&q->queue_lock);
 271
 272         return ret;
 273 }
 274
 275 static ssize_t queue_max_hw_sectors_show(struct request_queue *q, char *page)
 276 {
 277         int max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1;
 278
 279         return queue_var_show(max_hw_sectors_kb, page);
 280 }
 281
 282 static ssize_t queue_virt_boundary_mask_show(struct request_queue *q, char *page)
 283 {
 284         return queue_var_show(q->limits.virt_boundary_mask, page);
 285 }
 286
 287 static ssize_t queue_dma_alignment_show(struct request_queue *q, char *page)
 288 {
 289         return queue_var_show(queue_dma_alignment(q), page);
 290 }
 291
 292 #define QUEUE_SYSFS_BIT_FNS(name, flag, neg)                            \
 293 static ssize_t                                                          \
 294 queue_##name##_show(struct request_queue *q, char *page)                \
 295 {                                                                       \
 296         int bit;                                                        \
 297         bit = test_bit(QUEUE_FLAG_##flag, &q->queue_flags);             \
 298         return queue_var_show(neg ? !bit : bit, page);                  \
 299 }                                                                       \
 300 static ssize_t                                                          \
 301 queue_##name##_store(struct request_queue *q, const char *page, size_t count) \
 302 {                                                                       \
 303         unsigned long val;                                              \
 304         ssize_t ret;                                                    \
 305         ret = queue_var_store(&val, page, count);                       \
 306         if (ret < 0)                                                    \
 307                  return ret;                                            \
 308         if (neg)                                                        \
 309                 val = !val;                                             \
 310                                                                         \
 311         if (val)                                                        \
 312                 blk_queue_flag_set(QUEUE_FLAG_##flag, q);               \
 313         else                                                            \
 314                 blk_queue_flag_clear(QUEUE_FLAG_##flag, q);             \
 315         return ret;                                                     \
 316 }
 317
 318 QUEUE_SYSFS_BIT_FNS(nonrot, NONROT, 1);
 319 QUEUE_SYSFS_BIT_FNS(random, ADD_RANDOM, 0);
 320 QUEUE_SYSFS_BIT_FNS(iostats, IO_STAT, 0);
 321 QUEUE_SYSFS_BIT_FNS(stable_writes, STABLE_WRITES, 0);
 322 #undef QUEUE_SYSFS_BIT_FNS
 323
 324 static ssize_t queue_zoned_show(struct request_queue *q, char *page)
 325 {
 326         switch (blk_queue_zoned_model(q)) {
 327         case BLK_ZONED_HA:
 328                 return sprintf(page, "host-aware\n");
 329         case BLK_ZONED_HM:
 330                 return sprintf(page, "host-managed\n");
 331         default:
 332                 return sprintf(page, "none\n");
 333         }
 334 }
 335
 336 static ssize_t queue_nr_zones_show(struct request_queue *q, char *page)
 337 {
 338         return queue_var_show(disk_nr_zones(q->disk), page);
 339 }
 340
 341 static ssize_t queue_max_open_zones_show(struct request_queue *q, char *page)
 342 {
 343         return queue_var_show(bdev_max_open_zones(q->disk->part0), page);
 344 }
 345
 346 static ssize_t queue_max_active_zones_show(struct request_queue *q, char *page)
 347 {
 348         return queue_var_show(bdev_max_active_zones(q->disk->part0), page);
 349 }
 350
 351 static ssize_t queue_nomerges_show(struct request_queue *q, char *page)
 352 {
 353         return queue_var_show((blk_queue_nomerges(q) << 1) |
 354                                blk_queue_noxmerges(q), page);
 355 }
 356
 357 static ssize_t queue_nomerges_store(struct request_queue *q, const char *page,
 358                                     size_t count)
 359 {
 360         unsigned long nm;
 361         ssize_t ret = queue_var_store(&nm, page, count);
 362
 363         if (ret < 0)
 364                 return ret;
 365
 366         blk_queue_flag_clear(QUEUE_FLAG_NOMERGES, q);
 367         blk_queue_flag_clear(QUEUE_FLAG_NOXMERGES, q);
 368         if (nm == 2)
 369                 blk_queue_flag_set(QUEUE_FLAG_NOMERGES, q);
 370         else if (nm)
 371                 blk_queue_flag_set(QUEUE_FLAG_NOXMERGES, q);
 372
 373         return ret;
 374 }
 375
 376 static ssize_t queue_rq_affinity_show(struct request_queue *q, char *page)
 377 {
 378         bool set = test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags);
 379         bool force = test_bit(QUEUE_FLAG_SAME_FORCE, &q->queue_flags);
 380
 381         return queue_var_show(set << force, page);
 382 }
 383
 384 static ssize_t
 385 queue_rq_affinity_store(struct request_queue *q, const char *page, size_t count)
 386 {
 387         ssize_t ret = -EINVAL;
 388 #ifdef CONFIG_SMP
 389         unsigned long val;
 390
 391         ret = queue_var_store(&val, page, count);
 392         if (ret < 0)
 393                 return ret;
 394
 395         if (val == 2) {
 396                 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
 397                 blk_queue_flag_set(QUEUE_FLAG_SAME_FORCE, q);
 398         } else if (val == 1) {
 399                 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
 400                 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
 401         } else if (val == 0) {
 402                 blk_queue_flag_clear(QUEUE_FLAG_SAME_COMP, q);
 403                 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
 404         }
 405 #endif
 406         return ret;
 407 }
 408
 409 static ssize_t queue_poll_delay_show(struct request_queue *q, char *page)
 410 {
 411         int val;
 412
 413         if (q->poll_nsec == BLK_MQ_POLL_CLASSIC)
 414                 val = BLK_MQ_POLL_CLASSIC;
 415         else
 416                 val = q->poll_nsec / 1000;
 417
 418         return sprintf(page, "%d\n", val);
 419 }
 420
 421 static ssize_t queue_poll_delay_store(struct request_queue *q, const char *page,
 422                                 size_t count)
 423 {
 424         int err, val;
 425
 426         if (!q->mq_ops || !q->mq_ops->poll)
 427                 return -EINVAL;
 428
 429         err = kstrtoint(page, 10, &val);
 430         if (err < 0)
 431                 return err;
 432
 433         if (val == BLK_MQ_POLL_CLASSIC)
 434                 q->poll_nsec = BLK_MQ_POLL_CLASSIC;
 435         else if (val >= 0)
 436                 q->poll_nsec = val * 1000;
 437         else
 438                 return -EINVAL;
 439
 440         return count;
 441 }
 442
 443 static ssize_t queue_poll_show(struct request_queue *q, char *page)
 444 {
 445         return queue_var_show(test_bit(QUEUE_FLAG_POLL, &q->queue_flags), page);
 446 }
 447
 448 static ssize_t queue_poll_store(struct request_queue *q, const char *page,
 449                                 size_t count)
 450 {
 451         if (!test_bit(QUEUE_FLAG_POLL, &q->queue_flags))
 452                 return -EINVAL;
 453         pr_info_ratelimited("writes to the poll attribute are ignored.\n");
 454         pr_info_ratelimited("please use driver specific parameters instead.\n");
 455         return count;
 456 }
 457
 458 static ssize_t queue_io_timeout_show(struct request_queue *q, char *page)
 459 {
 460         return sprintf(page, "%u\n", jiffies_to_msecs(q->rq_timeout));
 461 }
 462
 463 static ssize_t queue_io_timeout_store(struct request_queue *q, const char *page,
 464                                   size_t count)
 465 {
 466         unsigned int val;
 467         int err;
 468
 469         err = kstrtou32(page, 10, &val);
 470         if (err || val == 0)
 471                 return -EINVAL;
 472
 473         blk_queue_rq_timeout(q, msecs_to_jiffies(val));
 474
 475         return count;
 476 }
 477
 478 static ssize_t queue_wb_lat_show(struct request_queue *q, char *page)
 479 {
 480         if (!wbt_rq_qos(q))
 481                 return -EINVAL;
 482
 483         if (wbt_disabled(q))
 484                 return sprintf(page, "0\n");
 485
 486         return sprintf(page, "%llu\n", div_u64(wbt_get_min_lat(q), 1000));
 487 }
 488
 489 static ssize_t queue_wb_lat_store(struct request_queue *q, const char *page,
 490                                   size_t count)
 491 {
 492         struct rq_qos *rqos;
 493         ssize_t ret;
 494         s64 val;
 495
 496         ret = queue_var_store64(&val, page);
 497         if (ret < 0)
 498                 return ret;
 499         if (val < -1)
 500                 return -EINVAL;
 501
 502         rqos = wbt_rq_qos(q);
 503         if (!rqos) {
 504                 ret = wbt_init(q->disk);
 505                 if (ret)
 506                         return ret;
 507         }
 508
 509         if (val == -1)
 510                 val = wbt_default_latency_nsec(q);
 511         else if (val >= 0)
 512                 val *= 1000ULL;
 513
 514         if (wbt_get_min_lat(q) == val)
 515                 return count;
 516
 517         /*
 518          * Ensure that the queue is idled, in case the latency update
 519          * ends up either enabling or disabling wbt completely. We can't
 520          * have IO inflight if that happens.
 521          */
 522         blk_mq_freeze_queue(q);
 523         blk_mq_quiesce_queue(q);
 524
 525         wbt_set_min_lat(q, val);
 526
 527         blk_mq_unquiesce_queue(q);
 528         blk_mq_unfreeze_queue(q);
 529
 530         return count;
 531 }
 532
 533 static ssize_t queue_wc_show(struct request_queue *q, char *page)
 534 {
 535         if (test_bit(QUEUE_FLAG_WC, &q->queue_flags))
 536                 return sprintf(page, "write back\n");
 537
 538         return sprintf(page, "write through\n");
 539 }
 540
 541 static ssize_t queue_wc_store(struct request_queue *q, const char *page,
 542                               size_t count)
 543 {
 544         int set = -1;
 545
 546         if (!strncmp(page, "write back", 10))
 547                 set = 1;
 548         else if (!strncmp(page, "write through", 13) ||
 549                  !strncmp(page, "none", 4))
 550                 set = 0;
 551
 552         if (set == -1)
 553                 return -EINVAL;
 554
 555         if (set)
 556                 blk_queue_flag_set(QUEUE_FLAG_WC, q);
 557         else
 558                 blk_queue_flag_clear(QUEUE_FLAG_WC, q);
 559
 560         return count;
 561 }
 562
 563 static ssize_t queue_fua_show(struct request_queue *q, char *page)
 564 {
 565         return sprintf(page, "%u\n", test_bit(QUEUE_FLAG_FUA, &q->queue_flags));
 566 }
 567
 568 static ssize_t queue_dax_show(struct request_queue *q, char *page)
 569 {
 570         return queue_var_show(blk_queue_dax(q), page);
 571 }
 572
 573 #define QUEUE_RO_ENTRY(_prefix, _name)                  \
 574 static struct queue_sysfs_entry _prefix##_entry = {     \
 575         .attr   = { .name = _name, .mode = 0444 },      \
 576         .show   = _prefix##_show,                       \
 577 };
 578
 579 #define QUEUE_RW_ENTRY(_prefix, _name)                  \
 580 static struct queue_sysfs_entry _prefix##_entry = {     \
 581         .attr   = { .name = _name, .mode = 0644 },      \
 582         .show   = _prefix##_show,                       \
 583         .store  = _prefix##_store,                      \
 584 };
 585
 586 QUEUE_RW_ENTRY(queue_requests, "nr_requests");
 587 QUEUE_RW_ENTRY(queue_ra, "read_ahead_kb");
 588 QUEUE_RW_ENTRY(queue_max_sectors, "max_sectors_kb");
 589 QUEUE_RO_ENTRY(queue_max_hw_sectors, "max_hw_sectors_kb");
 590 QUEUE_RO_ENTRY(queue_max_segments, "max_segments");
 591 QUEUE_RO_ENTRY(queue_max_integrity_segments, "max_integrity_segments");
 592 QUEUE_RO_ENTRY(queue_max_segment_size, "max_segment_size");
 593 QUEUE_RW_ENTRY(elv_iosched, "scheduler");
 594
 595 QUEUE_RO_ENTRY(queue_logical_block_size, "logical_block_size");
 596 QUEUE_RO_ENTRY(queue_physical_block_size, "physical_block_size");
 597 QUEUE_RO_ENTRY(queue_chunk_sectors, "chunk_sectors");
 598 QUEUE_RO_ENTRY(queue_io_min, "minimum_io_size");
 599 QUEUE_RO_ENTRY(queue_io_opt, "optimal_io_size");
 600
 601 QUEUE_RO_ENTRY(queue_max_discard_segments, "max_discard_segments");
 602 QUEUE_RO_ENTRY(queue_discard_granularity, "discard_granularity");
 603 QUEUE_RO_ENTRY(queue_discard_max_hw, "discard_max_hw_bytes");
 604 QUEUE_RW_ENTRY(queue_discard_max, "discard_max_bytes");
 605 QUEUE_RO_ENTRY(queue_discard_zeroes_data, "discard_zeroes_data");
 606
 607 QUEUE_RO_ENTRY(queue_write_same_max, "write_same_max_bytes");
 608 QUEUE_RO_ENTRY(queue_write_zeroes_max, "write_zeroes_max_bytes");
 609 QUEUE_RO_ENTRY(queue_zone_append_max, "zone_append_max_bytes");
 610 QUEUE_RO_ENTRY(queue_zone_write_granularity, "zone_write_granularity");
 611
 612 QUEUE_RO_ENTRY(queue_zoned, "zoned");
 613 QUEUE_RO_ENTRY(queue_nr_zones, "nr_zones");
 614 QUEUE_RO_ENTRY(queue_max_open_zones, "max_open_zones");
 615 QUEUE_RO_ENTRY(queue_max_active_zones, "max_active_zones");
 616
 617 QUEUE_RW_ENTRY(queue_nomerges, "nomerges");
 618 QUEUE_RW_ENTRY(queue_rq_affinity, "rq_affinity");
 619 QUEUE_RW_ENTRY(queue_poll, "io_poll");
 620 QUEUE_RW_ENTRY(queue_poll_delay, "io_poll_delay");
 621 QUEUE_RW_ENTRY(queue_wc, "write_cache");
 622 QUEUE_RO_ENTRY(queue_fua, "fua");
 623 QUEUE_RO_ENTRY(queue_dax, "dax");
 624 QUEUE_RW_ENTRY(queue_io_timeout, "io_timeout");
 625 QUEUE_RW_ENTRY(queue_wb_lat, "wbt_lat_usec");
 626 QUEUE_RO_ENTRY(queue_virt_boundary_mask, "virt_boundary_mask");
 627 QUEUE_RO_ENTRY(queue_dma_alignment, "dma_alignment");
 628
 629 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW
 630 QUEUE_RW_ENTRY(blk_throtl_sample_time, "throttle_sample_time");
 631 #endif
 632
 633 /* legacy alias for logical_block_size: */
 634 static struct queue_sysfs_entry queue_hw_sector_size_entry = {
 635         .attr = {.name = "hw_sector_size", .mode = 0444 },
 636         .show = queue_logical_block_size_show,
 637 };
 638
 639 QUEUE_RW_ENTRY(queue_nonrot, "rotational");
 640 QUEUE_RW_ENTRY(queue_iostats, "iostats");
 641 QUEUE_RW_ENTRY(queue_random, "add_random");
 642 QUEUE_RW_ENTRY(queue_stable_writes, "stable_writes");
 643
 644 static struct attribute *queue_attrs[] = {
 645         &queue_requests_entry.attr,
 646         &queue_ra_entry.attr,
 647         &queue_max_hw_sectors_entry.attr,
 648         &queue_max_sectors_entry.attr,
 649         &queue_max_segments_entry.attr,
 650         &queue_max_discard_segments_entry.attr,
 651         &queue_max_integrity_segments_entry.attr,
 652         &queue_max_segment_size_entry.attr,
 653         &elv_iosched_entry.attr,
 654         &queue_hw_sector_size_entry.attr,
 655         &queue_logical_block_size_entry.attr,
 656         &queue_physical_block_size_entry.attr,
 657         &queue_chunk_sectors_entry.attr,
 658         &queue_io_min_entry.attr,
 659         &queue_io_opt_entry.attr,
 660         &queue_discard_granularity_entry.attr,
 661         &queue_discard_max_entry.attr,
 662         &queue_discard_max_hw_entry.attr,
 663         &queue_discard_zeroes_data_entry.attr,
 664         &queue_write_same_max_entry.attr,
 665         &queue_write_zeroes_max_entry.attr,
 666         &queue_zone_append_max_entry.attr,
 667         &queue_zone_write_granularity_entry.attr,
 668         &queue_nonrot_entry.attr,
 669         &queue_zoned_entry.attr,
 670         &queue_nr_zones_entry.attr,
 671         &queue_max_open_zones_entry.attr,
 672         &queue_max_active_zones_entry.attr,
 673         &queue_nomerges_entry.attr,
 674         &queue_rq_affinity_entry.attr,
 675         &queue_iostats_entry.attr,
 676         &queue_stable_writes_entry.attr,
 677         &queue_random_entry.attr,
 678         &queue_poll_entry.attr,
 679         &queue_wc_entry.attr,
 680         &queue_fua_entry.attr,
 681         &queue_dax_entry.attr,
 682         &queue_wb_lat_entry.attr,
 683         &queue_poll_delay_entry.attr,
 684         &queue_io_timeout_entry.attr,
 685 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW
 686         &blk_throtl_sample_time_entry.attr,
 687 #endif
 688         &queue_virt_boundary_mask_entry.attr,
 689         &queue_dma_alignment_entry.attr,
 690         NULL,
 691 };
 692
 693 static umode_t queue_attr_visible(struct kobject *kobj, struct attribute *attr,
 694                                 int n)
 695 {
 696         struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj);
 697         struct request_queue *q = disk->queue;
 698
 699         if (attr == &queue_io_timeout_entry.attr &&
 700                 (!q->mq_ops || !q->mq_ops->timeout))
 701                         return 0;
 702
 703         if ((attr == &queue_max_open_zones_entry.attr ||
 704              attr == &queue_max_active_zones_entry.attr) &&
 705             !blk_queue_is_zoned(q))
 706                 return 0;
 707
 708         return attr->mode;
 709 }
 710
 711 static struct attribute_group queue_attr_group = {
 712         .attrs = queue_attrs,
 713         .is_visible = queue_attr_visible,
 714 };
 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         NULL
 761 };
 762
 763 static void blk_queue_release(struct kobject *kobj)
 764 {
 765         /* nothing to do here, all data is associated with the parent gendisk */
 766 }
 767
 768 static const struct kobj_type blk_queue_ktype = {
 769         .default_groups = blk_queue_attr_groups,
 770         .sysfs_ops      = &queue_sysfs_ops,
 771         .release        = blk_queue_release,
 772 };
 773
 774 static void blk_debugfs_remove(struct gendisk *disk)
 775 {
 776         struct request_queue *q = disk->queue;
 777
 778         mutex_lock(&q->debugfs_mutex);
 779         blk_trace_shutdown(q);
 780         debugfs_remove_recursive(q->debugfs_dir);
 781         q->debugfs_dir = NULL;
 782         q->sched_debugfs_dir = NULL;
 783         q->rqos_debugfs_dir = NULL;
 784         mutex_unlock(&q->debugfs_mutex);
 785 }
 786
 787 /**
 788  * blk_register_queue - register a block layer queue with sysfs
 789  * @disk: Disk of which the request queue should be registered with sysfs.
 790  */
 791 int blk_register_queue(struct gendisk *disk)
 792 {
 793         struct request_queue *q = disk->queue;
 794         int ret;
 795
 796         mutex_lock(&q->sysfs_dir_lock);
 797         kobject_init(&disk->queue_kobj, &blk_queue_ktype);
 798         ret = kobject_add(&disk->queue_kobj, &disk_to_dev(disk)->kobj, "queue");
 799         if (ret < 0)
 800                 goto out_put_queue_kobj;
 801
 802         if (queue_is_mq(q)) {
 803                 ret = blk_mq_sysfs_register(disk);
 804                 if (ret)
 805                         goto out_put_queue_kobj;
 806         }
 807         mutex_lock(&q->sysfs_lock);
 808
 809         mutex_lock(&q->debugfs_mutex);
 810         q->debugfs_dir = debugfs_create_dir(disk->disk_name, blk_debugfs_root);
 811         if (queue_is_mq(q))
 812                 blk_mq_debugfs_register(q);
 813         mutex_unlock(&q->debugfs_mutex);
 814
 815         ret = disk_register_independent_access_ranges(disk);
 816         if (ret)
 817                 goto out_debugfs_remove;
 818
 819         if (q->elevator) {
 820                 ret = elv_register_queue(q, false);
 821                 if (ret)
 822                         goto out_unregister_ia_ranges;
 823         }
 824
 825         ret = blk_crypto_sysfs_register(disk);
 826         if (ret)
 827                 goto out_elv_unregister;
 828
 829         blk_queue_flag_set(QUEUE_FLAG_REGISTERED, q);
 830         wbt_enable_default(disk);
 831         blk_throtl_register(disk);
 832
 833         /* Now everything is ready and send out KOBJ_ADD uevent */
 834         kobject_uevent(&disk->queue_kobj, KOBJ_ADD);
 835         if (q->elevator)
 836                 kobject_uevent(&q->elevator->kobj, KOBJ_ADD);
 837         mutex_unlock(&q->sysfs_lock);
 838         mutex_unlock(&q->sysfs_dir_lock);
 839
 840         /*
 841          * SCSI probing may synchronously create and destroy a lot of
 842          * request_queues for non-existent devices.  Shutting down a fully
 843          * functional queue takes measureable wallclock time as RCU grace
 844          * periods are involved.  To avoid excessive latency in these
 845          * cases, a request_queue starts out in a degraded mode which is
 846          * faster to shut down and is made fully functional here as
 847          * request_queues for non-existent devices never get registered.
 848          */
 849         if (!blk_queue_init_done(q)) {
 850                 blk_queue_flag_set(QUEUE_FLAG_INIT_DONE, q);
 851                 percpu_ref_switch_to_percpu(&q->q_usage_counter);
 852         }
 853
 854         return ret;
 855
 856 out_elv_unregister:
 857         elv_unregister_queue(q);
 858 out_unregister_ia_ranges:
 859         disk_unregister_independent_access_ranges(disk);
 860 out_debugfs_remove:
 861         blk_debugfs_remove(disk);
 862         mutex_unlock(&q->sysfs_lock);
 863 out_put_queue_kobj:
 864         kobject_put(&disk->queue_kobj);
 865         mutex_unlock(&q->sysfs_dir_lock);
 866         return ret;
 867 }
 868
 869 /**
 870  * blk_unregister_queue - counterpart of blk_register_queue()
 871  * @disk: Disk of which the request queue should be unregistered from sysfs.
 872  *
 873  * Note: the caller is responsible for guaranteeing that this function is called
 874  * after blk_register_queue() has finished.
 875  */
 876 void blk_unregister_queue(struct gendisk *disk)
 877 {
 878         struct request_queue *q = disk->queue;
 879
 880         if (WARN_ON(!q))
 881                 return;
 882
 883         /* Return early if disk->queue was never registered. */
 884         if (!blk_queue_registered(q))
 885                 return;
 886
 887         /*
 888          * Since sysfs_remove_dir() prevents adding new directory entries
 889          * before removal of existing entries starts, protect against
 890          * concurrent elv_iosched_store() calls.
 891          */
 892         mutex_lock(&q->sysfs_lock);
 893         blk_queue_flag_clear(QUEUE_FLAG_REGISTERED, q);
 894         mutex_unlock(&q->sysfs_lock);
 895
 896         mutex_lock(&q->sysfs_dir_lock);
 897         /*
 898          * Remove the sysfs attributes before unregistering the queue data
 899          * structures that can be modified through sysfs.
 900          */
 901         if (queue_is_mq(q))
 902                 blk_mq_sysfs_unregister(disk);
 903         blk_crypto_sysfs_unregister(disk);
 904
 905         mutex_lock(&q->sysfs_lock);
 906         elv_unregister_queue(q);
 907         disk_unregister_independent_access_ranges(disk);
 908         mutex_unlock(&q->sysfs_lock);
 909
 910         /* Now that we've deleted all child objects, we can delete the queue. */
 911         kobject_uevent(&disk->queue_kobj, KOBJ_REMOVE);
 912         kobject_del(&disk->queue_kobj);
 913         mutex_unlock(&q->sysfs_dir_lock);
 914
 915         blk_debugfs_remove(disk);
 916 }