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