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 ssize_t (*show_limit)(struct gendisk *disk, char *page); 27 28 ssize_t (*store)(struct gendisk *disk, const char *page, size_t count); 29 int (*store_limit)(struct gendisk *disk, const char *page, 30 size_t count, struct queue_limits *lim); 31 }; 32 33 static ssize_t 34 queue_var_show(unsigned long var, char *page) 35 { 36 return sysfs_emit(page, "%lu\n", var); 37 } 38 39 static ssize_t 40 queue_var_store(unsigned long *var, const char *page, size_t count) 41 { 42 int err; 43 unsigned long v; 44 45 err = kstrtoul(page, 10, &v); 46 if (err || v > UINT_MAX) 47 return -EINVAL; 48 49 *var = v; 50 51 return count; 52 } 53 54 static ssize_t queue_requests_show(struct gendisk *disk, char *page) 55 { 56 ssize_t ret; 57 58 mutex_lock(&disk->queue->elevator_lock); 59 ret = queue_var_show(disk->queue->nr_requests, page); 60 mutex_unlock(&disk->queue->elevator_lock); 61 return ret; 62 } 63 64 static ssize_t 65 queue_requests_store(struct gendisk *disk, const char *page, size_t count) 66 { 67 struct request_queue *q = disk->queue; 68 struct blk_mq_tag_set *set = q->tag_set; 69 struct elevator_tags *et = NULL; 70 unsigned int memflags; 71 unsigned long nr; 72 int ret; 73 74 ret = queue_var_store(&nr, page, count); 75 if (ret < 0) 76 return ret; 77 78 /* 79 * Serialize updating nr_requests with concurrent queue_requests_store() 80 * and switching elevator. 81 * 82 * Use trylock to avoid circular lock dependency with kernfs active 83 * reference during concurrent disk deletion: 84 * update_nr_hwq_lock -> kn->active (via del_gendisk -> kobject_del) 85 * kn->active -> update_nr_hwq_lock (via this sysfs write path) 86 */ 87 if (!down_write_trylock(&set->update_nr_hwq_lock)) 88 return -EBUSY; 89 90 if (nr == q->nr_requests) 91 goto unlock; 92 93 if (nr < BLKDEV_MIN_RQ) 94 nr = BLKDEV_MIN_RQ; 95 96 /* 97 * Switching elevator is protected by update_nr_hwq_lock: 98 * - read lock is held from elevator sysfs attribute; 99 * - write lock is held from updating nr_hw_queues; 100 * Hence it's safe to access q->elevator here with write lock held. 101 */ 102 if (nr <= set->reserved_tags || 103 (q->elevator && nr > MAX_SCHED_RQ) || 104 (!q->elevator && nr > set->queue_depth)) { 105 ret = -EINVAL; 106 goto unlock; 107 } 108 109 if (!blk_mq_is_shared_tags(set->flags) && q->elevator && 110 nr > q->elevator->et->nr_requests) { 111 /* 112 * Tags will grow, allocate memory before freezing queue to 113 * prevent deadlock. 114 */ 115 et = blk_mq_alloc_sched_tags(set, q->nr_hw_queues, nr); 116 if (!et) { 117 ret = -ENOMEM; 118 goto unlock; 119 } 120 } 121 122 memflags = blk_mq_freeze_queue(q); 123 mutex_lock(&q->elevator_lock); 124 et = blk_mq_update_nr_requests(q, et, nr); 125 mutex_unlock(&q->elevator_lock); 126 blk_mq_unfreeze_queue(q, memflags); 127 128 if (et) 129 blk_mq_free_sched_tags(et, set); 130 131 unlock: 132 up_write(&set->update_nr_hwq_lock); 133 return ret; 134 } 135 136 static ssize_t queue_async_depth_show(struct gendisk *disk, char *page) 137 { 138 guard(mutex)(&disk->queue->elevator_lock); 139 140 return queue_var_show(disk->queue->async_depth, page); 141 } 142 143 static ssize_t 144 queue_async_depth_store(struct gendisk *disk, const char *page, size_t count) 145 { 146 struct request_queue *q = disk->queue; 147 unsigned int memflags; 148 unsigned long nr; 149 int ret; 150 151 if (!queue_is_mq(q)) 152 return -EINVAL; 153 154 ret = queue_var_store(&nr, page, count); 155 if (ret < 0) 156 return ret; 157 158 if (nr == 0) 159 return -EINVAL; 160 161 memflags = blk_mq_freeze_queue(q); 162 scoped_guard(mutex, &q->elevator_lock) { 163 if (q->elevator) { 164 q->async_depth = min(q->nr_requests, nr); 165 if (q->elevator->type->ops.depth_updated) 166 q->elevator->type->ops.depth_updated(q); 167 } else { 168 ret = -EINVAL; 169 } 170 } 171 blk_mq_unfreeze_queue(q, memflags); 172 173 return ret; 174 } 175 176 static ssize_t queue_ra_show(struct gendisk *disk, char *page) 177 { 178 ssize_t ret; 179 180 mutex_lock(&disk->queue->limits_lock); 181 ret = queue_var_show(disk->bdi->ra_pages << (PAGE_SHIFT - 10), page); 182 mutex_unlock(&disk->queue->limits_lock); 183 184 return ret; 185 } 186 187 static ssize_t 188 queue_ra_store(struct gendisk *disk, const char *page, size_t count) 189 { 190 unsigned long ra_kb; 191 ssize_t ret; 192 struct request_queue *q = disk->queue; 193 194 ret = queue_var_store(&ra_kb, page, count); 195 if (ret < 0) 196 return ret; 197 /* 198 * The ->ra_pages change below is protected by ->limits_lock because it 199 * is usually calculated from the queue limits by 200 * queue_limits_commit_update(). 201 * 202 * bdi->ra_pages reads are not serialized against bdi->ra_pages writes. 203 * Use WRITE_ONCE() to write bdi->ra_pages once. 204 */ 205 mutex_lock(&q->limits_lock); 206 WRITE_ONCE(disk->bdi->ra_pages, ra_kb >> (PAGE_SHIFT - 10)); 207 mutex_unlock(&q->limits_lock); 208 209 return ret; 210 } 211 212 #define QUEUE_SYSFS_LIMIT_SHOW(_field) \ 213 static ssize_t queue_##_field##_show(struct gendisk *disk, char *page) \ 214 { \ 215 return queue_var_show(disk->queue->limits._field, page); \ 216 } 217 218 QUEUE_SYSFS_LIMIT_SHOW(max_segments) 219 QUEUE_SYSFS_LIMIT_SHOW(max_discard_segments) 220 QUEUE_SYSFS_LIMIT_SHOW(max_integrity_segments) 221 QUEUE_SYSFS_LIMIT_SHOW(max_segment_size) 222 QUEUE_SYSFS_LIMIT_SHOW(max_write_streams) 223 QUEUE_SYSFS_LIMIT_SHOW(write_stream_granularity) 224 QUEUE_SYSFS_LIMIT_SHOW(logical_block_size) 225 QUEUE_SYSFS_LIMIT_SHOW(physical_block_size) 226 QUEUE_SYSFS_LIMIT_SHOW(chunk_sectors) 227 QUEUE_SYSFS_LIMIT_SHOW(io_min) 228 QUEUE_SYSFS_LIMIT_SHOW(io_opt) 229 QUEUE_SYSFS_LIMIT_SHOW(discard_granularity) 230 QUEUE_SYSFS_LIMIT_SHOW(zone_write_granularity) 231 QUEUE_SYSFS_LIMIT_SHOW(virt_boundary_mask) 232 QUEUE_SYSFS_LIMIT_SHOW(dma_alignment) 233 QUEUE_SYSFS_LIMIT_SHOW(max_open_zones) 234 QUEUE_SYSFS_LIMIT_SHOW(max_active_zones) 235 QUEUE_SYSFS_LIMIT_SHOW(atomic_write_unit_min) 236 QUEUE_SYSFS_LIMIT_SHOW(atomic_write_unit_max) 237 238 #define QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(_field) \ 239 static ssize_t queue_##_field##_show(struct gendisk *disk, char *page) \ 240 { \ 241 return sysfs_emit(page, "%llu\n", \ 242 (unsigned long long)disk->queue->limits._field << \ 243 SECTOR_SHIFT); \ 244 } 245 246 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(max_discard_sectors) 247 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(max_hw_discard_sectors) 248 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(max_write_zeroes_sectors) 249 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(max_hw_wzeroes_unmap_sectors) 250 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(max_wzeroes_unmap_sectors) 251 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(atomic_write_max_sectors) 252 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(atomic_write_boundary_sectors) 253 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(max_zone_append_sectors) 254 255 #define QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_KB(_field) \ 256 static ssize_t queue_##_field##_show(struct gendisk *disk, char *page) \ 257 { \ 258 return queue_var_show(disk->queue->limits._field >> 1, page); \ 259 } 260 261 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_KB(max_sectors) 262 QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_KB(max_hw_sectors) 263 264 #define QUEUE_SYSFS_SHOW_CONST(_name, _val) \ 265 static ssize_t queue_##_name##_show(struct gendisk *disk, char *page) \ 266 { \ 267 return sysfs_emit(page, "%d\n", _val); \ 268 } 269 270 /* deprecated fields */ 271 QUEUE_SYSFS_SHOW_CONST(discard_zeroes_data, 0) 272 QUEUE_SYSFS_SHOW_CONST(write_same_max, 0) 273 QUEUE_SYSFS_SHOW_CONST(poll_delay, -1) 274 275 static int queue_max_discard_sectors_store(struct gendisk *disk, 276 const char *page, size_t count, struct queue_limits *lim) 277 { 278 unsigned long max_discard_bytes; 279 ssize_t ret; 280 281 ret = queue_var_store(&max_discard_bytes, page, count); 282 if (ret < 0) 283 return ret; 284 285 if (max_discard_bytes & (disk->queue->limits.discard_granularity - 1)) 286 return -EINVAL; 287 288 if ((max_discard_bytes >> SECTOR_SHIFT) > UINT_MAX) 289 return -EINVAL; 290 291 lim->max_user_discard_sectors = max_discard_bytes >> SECTOR_SHIFT; 292 return 0; 293 } 294 295 static int queue_max_wzeroes_unmap_sectors_store(struct gendisk *disk, 296 const char *page, size_t count, struct queue_limits *lim) 297 { 298 unsigned long max_zeroes_bytes, max_hw_zeroes_bytes; 299 ssize_t ret; 300 301 ret = queue_var_store(&max_zeroes_bytes, page, count); 302 if (ret < 0) 303 return ret; 304 305 max_hw_zeroes_bytes = lim->max_hw_wzeroes_unmap_sectors << SECTOR_SHIFT; 306 if (max_zeroes_bytes != 0 && max_zeroes_bytes != max_hw_zeroes_bytes) 307 return -EINVAL; 308 309 lim->max_user_wzeroes_unmap_sectors = max_zeroes_bytes >> SECTOR_SHIFT; 310 return 0; 311 } 312 313 static int 314 queue_max_sectors_store(struct gendisk *disk, const char *page, size_t count, 315 struct queue_limits *lim) 316 { 317 unsigned long max_sectors_kb; 318 ssize_t ret; 319 320 ret = queue_var_store(&max_sectors_kb, page, count); 321 if (ret < 0) 322 return ret; 323 324 lim->max_user_sectors = max_sectors_kb << 1; 325 return 0; 326 } 327 328 static ssize_t queue_feature_store(struct gendisk *disk, const char *page, 329 size_t count, struct queue_limits *lim, blk_features_t feature) 330 { 331 unsigned long val; 332 ssize_t ret; 333 334 ret = queue_var_store(&val, page, count); 335 if (ret < 0) 336 return ret; 337 338 if (val) 339 lim->features |= feature; 340 else 341 lim->features &= ~feature; 342 return 0; 343 } 344 345 #define QUEUE_SYSFS_FEATURE(_name, _feature) \ 346 static ssize_t queue_##_name##_show(struct gendisk *disk, char *page) \ 347 { \ 348 return sysfs_emit(page, "%u\n", \ 349 !!(disk->queue->limits.features & _feature)); \ 350 } \ 351 static int queue_##_name##_store(struct gendisk *disk, \ 352 const char *page, size_t count, struct queue_limits *lim) \ 353 { \ 354 return queue_feature_store(disk, page, count, lim, _feature); \ 355 } 356 357 QUEUE_SYSFS_FEATURE(rotational, BLK_FEAT_ROTATIONAL) 358 QUEUE_SYSFS_FEATURE(add_random, BLK_FEAT_ADD_RANDOM) 359 QUEUE_SYSFS_FEATURE(iostats, BLK_FEAT_IO_STAT) 360 QUEUE_SYSFS_FEATURE(stable_writes, BLK_FEAT_STABLE_WRITES); 361 362 #define QUEUE_SYSFS_FEATURE_SHOW(_name, _feature) \ 363 static ssize_t queue_##_name##_show(struct gendisk *disk, char *page) \ 364 { \ 365 return sysfs_emit(page, "%u\n", \ 366 !!(disk->queue->limits.features & _feature)); \ 367 } 368 369 QUEUE_SYSFS_FEATURE_SHOW(fua, BLK_FEAT_FUA); 370 QUEUE_SYSFS_FEATURE_SHOW(dax, BLK_FEAT_DAX); 371 372 static ssize_t queue_poll_show(struct gendisk *disk, char *page) 373 { 374 if (queue_is_mq(disk->queue)) 375 return sysfs_emit(page, "%u\n", blk_mq_can_poll(disk->queue)); 376 377 return sysfs_emit(page, "%u\n", 378 !!(disk->queue->limits.features & BLK_FEAT_POLL)); 379 } 380 381 static ssize_t queue_zoned_show(struct gendisk *disk, char *page) 382 { 383 if (blk_queue_is_zoned(disk->queue)) 384 return sysfs_emit(page, "host-managed\n"); 385 return sysfs_emit(page, "none\n"); 386 } 387 388 static ssize_t queue_nr_zones_show(struct gendisk *disk, char *page) 389 { 390 return queue_var_show(disk_nr_zones(disk), page); 391 } 392 393 static ssize_t queue_iostats_passthrough_show(struct gendisk *disk, char *page) 394 { 395 return queue_var_show(!!blk_queue_passthrough_stat(disk->queue), page); 396 } 397 398 static int queue_iostats_passthrough_store(struct gendisk *disk, 399 const char *page, size_t count, struct queue_limits *lim) 400 { 401 unsigned long ios; 402 ssize_t ret; 403 404 ret = queue_var_store(&ios, page, count); 405 if (ret < 0) 406 return ret; 407 408 if (ios) 409 lim->flags |= BLK_FLAG_IOSTATS_PASSTHROUGH; 410 else 411 lim->flags &= ~BLK_FLAG_IOSTATS_PASSTHROUGH; 412 return 0; 413 } 414 415 static ssize_t queue_nomerges_show(struct gendisk *disk, char *page) 416 { 417 return queue_var_show((blk_queue_nomerges(disk->queue) << 1) | 418 blk_queue_noxmerges(disk->queue), page); 419 } 420 421 static ssize_t queue_nomerges_store(struct gendisk *disk, const char *page, 422 size_t count) 423 { 424 unsigned long nm; 425 struct request_queue *q = disk->queue; 426 ssize_t ret = queue_var_store(&nm, page, count); 427 428 if (ret < 0) 429 return ret; 430 431 blk_queue_flag_clear(QUEUE_FLAG_NOMERGES, q); 432 blk_queue_flag_clear(QUEUE_FLAG_NOXMERGES, q); 433 if (nm == 2) 434 blk_queue_flag_set(QUEUE_FLAG_NOMERGES, q); 435 else if (nm) 436 blk_queue_flag_set(QUEUE_FLAG_NOXMERGES, q); 437 438 return ret; 439 } 440 441 static ssize_t queue_rq_affinity_show(struct gendisk *disk, char *page) 442 { 443 bool set = test_bit(QUEUE_FLAG_SAME_COMP, &disk->queue->queue_flags); 444 bool force = test_bit(QUEUE_FLAG_SAME_FORCE, &disk->queue->queue_flags); 445 446 return queue_var_show(set << force, page); 447 } 448 449 static ssize_t 450 queue_rq_affinity_store(struct gendisk *disk, const char *page, size_t count) 451 { 452 ssize_t ret = -EINVAL; 453 #ifdef CONFIG_SMP 454 struct request_queue *q = disk->queue; 455 unsigned long val; 456 457 ret = queue_var_store(&val, page, count); 458 if (ret < 0) 459 return ret; 460 461 /* 462 * Here we update two queue flags each using atomic bitops, although 463 * updating two flags isn't atomic it should be harmless as those flags 464 * are accessed individually using atomic test_bit operation. So we 465 * don't grab any lock while updating these flags. 466 */ 467 if (val == 2) { 468 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q); 469 blk_queue_flag_set(QUEUE_FLAG_SAME_FORCE, q); 470 } else if (val == 1) { 471 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q); 472 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q); 473 } else if (val == 0) { 474 blk_queue_flag_clear(QUEUE_FLAG_SAME_COMP, q); 475 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q); 476 } 477 #endif 478 return ret; 479 } 480 481 static ssize_t queue_poll_delay_store(struct gendisk *disk, const char *page, 482 size_t count) 483 { 484 return count; 485 } 486 487 static ssize_t queue_poll_store(struct gendisk *disk, const char *page, 488 size_t count) 489 { 490 ssize_t ret = count; 491 struct request_queue *q = disk->queue; 492 493 if (!(q->limits.features & BLK_FEAT_POLL)) { 494 ret = -EINVAL; 495 goto out; 496 } 497 498 pr_info_ratelimited("writes to the poll attribute are ignored.\n"); 499 pr_info_ratelimited("please use driver specific parameters instead.\n"); 500 out: 501 return ret; 502 } 503 504 static ssize_t queue_io_timeout_show(struct gendisk *disk, char *page) 505 { 506 return sysfs_emit(page, "%u\n", 507 jiffies_to_msecs(READ_ONCE(disk->queue->rq_timeout))); 508 } 509 510 static ssize_t queue_io_timeout_store(struct gendisk *disk, const char *page, 511 size_t count) 512 { 513 unsigned int val; 514 int err; 515 struct request_queue *q = disk->queue; 516 517 err = kstrtou32(page, 10, &val); 518 if (err || val == 0) 519 return -EINVAL; 520 521 blk_queue_rq_timeout(q, msecs_to_jiffies(val)); 522 523 return count; 524 } 525 526 static ssize_t queue_wc_show(struct gendisk *disk, char *page) 527 { 528 if (blk_queue_write_cache(disk->queue)) 529 return sysfs_emit(page, "write back\n"); 530 return sysfs_emit(page, "write through\n"); 531 } 532 533 static int queue_wc_store(struct gendisk *disk, const char *page, 534 size_t count, struct queue_limits *lim) 535 { 536 bool disable; 537 538 if (!strncmp(page, "write back", 10)) { 539 disable = false; 540 } else if (!strncmp(page, "write through", 13) || 541 !strncmp(page, "none", 4)) { 542 disable = true; 543 } else { 544 return -EINVAL; 545 } 546 547 if (disable) 548 lim->flags |= BLK_FLAG_WRITE_CACHE_DISABLED; 549 else 550 lim->flags &= ~BLK_FLAG_WRITE_CACHE_DISABLED; 551 return 0; 552 } 553 554 #define QUEUE_RO_ENTRY(_prefix, _name) \ 555 static struct queue_sysfs_entry _prefix##_entry = { \ 556 .attr = { .name = _name, .mode = 0444 }, \ 557 .show = _prefix##_show, \ 558 }; 559 560 #define QUEUE_RW_ENTRY(_prefix, _name) \ 561 static struct queue_sysfs_entry _prefix##_entry = { \ 562 .attr = { .name = _name, .mode = 0644 }, \ 563 .show = _prefix##_show, \ 564 .store = _prefix##_store, \ 565 }; 566 567 #define QUEUE_LIM_RO_ENTRY(_prefix, _name) \ 568 static struct queue_sysfs_entry _prefix##_entry = { \ 569 .attr = { .name = _name, .mode = 0444 }, \ 570 .show_limit = _prefix##_show, \ 571 } 572 573 #define QUEUE_LIM_RW_ENTRY(_prefix, _name) \ 574 static struct queue_sysfs_entry _prefix##_entry = { \ 575 .attr = { .name = _name, .mode = 0644 }, \ 576 .show_limit = _prefix##_show, \ 577 .store_limit = _prefix##_store, \ 578 } 579 580 QUEUE_RW_ENTRY(queue_requests, "nr_requests"); 581 QUEUE_RW_ENTRY(queue_async_depth, "async_depth"); 582 QUEUE_RW_ENTRY(queue_ra, "read_ahead_kb"); 583 QUEUE_LIM_RW_ENTRY(queue_max_sectors, "max_sectors_kb"); 584 QUEUE_LIM_RO_ENTRY(queue_max_hw_sectors, "max_hw_sectors_kb"); 585 QUEUE_LIM_RO_ENTRY(queue_max_segments, "max_segments"); 586 QUEUE_LIM_RO_ENTRY(queue_max_integrity_segments, "max_integrity_segments"); 587 QUEUE_LIM_RO_ENTRY(queue_max_segment_size, "max_segment_size"); 588 QUEUE_LIM_RO_ENTRY(queue_max_write_streams, "max_write_streams"); 589 QUEUE_LIM_RO_ENTRY(queue_write_stream_granularity, "write_stream_granularity"); 590 QUEUE_RW_ENTRY(elv_iosched, "scheduler"); 591 592 QUEUE_LIM_RO_ENTRY(queue_logical_block_size, "logical_block_size"); 593 QUEUE_LIM_RO_ENTRY(queue_physical_block_size, "physical_block_size"); 594 QUEUE_LIM_RO_ENTRY(queue_chunk_sectors, "chunk_sectors"); 595 QUEUE_LIM_RO_ENTRY(queue_io_min, "minimum_io_size"); 596 QUEUE_LIM_RO_ENTRY(queue_io_opt, "optimal_io_size"); 597 598 QUEUE_LIM_RO_ENTRY(queue_max_discard_segments, "max_discard_segments"); 599 QUEUE_LIM_RO_ENTRY(queue_discard_granularity, "discard_granularity"); 600 QUEUE_LIM_RO_ENTRY(queue_max_hw_discard_sectors, "discard_max_hw_bytes"); 601 QUEUE_LIM_RW_ENTRY(queue_max_discard_sectors, "discard_max_bytes"); 602 QUEUE_RO_ENTRY(queue_discard_zeroes_data, "discard_zeroes_data"); 603 604 QUEUE_LIM_RO_ENTRY(queue_atomic_write_max_sectors, "atomic_write_max_bytes"); 605 QUEUE_LIM_RO_ENTRY(queue_atomic_write_boundary_sectors, 606 "atomic_write_boundary_bytes"); 607 QUEUE_LIM_RO_ENTRY(queue_atomic_write_unit_max, "atomic_write_unit_max_bytes"); 608 QUEUE_LIM_RO_ENTRY(queue_atomic_write_unit_min, "atomic_write_unit_min_bytes"); 609 610 QUEUE_RO_ENTRY(queue_write_same_max, "write_same_max_bytes"); 611 QUEUE_LIM_RO_ENTRY(queue_max_write_zeroes_sectors, "write_zeroes_max_bytes"); 612 QUEUE_LIM_RO_ENTRY(queue_max_hw_wzeroes_unmap_sectors, 613 "write_zeroes_unmap_max_hw_bytes"); 614 QUEUE_LIM_RW_ENTRY(queue_max_wzeroes_unmap_sectors, 615 "write_zeroes_unmap_max_bytes"); 616 QUEUE_LIM_RO_ENTRY(queue_max_zone_append_sectors, "zone_append_max_bytes"); 617 QUEUE_LIM_RO_ENTRY(queue_zone_write_granularity, "zone_write_granularity"); 618 619 QUEUE_LIM_RO_ENTRY(queue_zoned, "zoned"); 620 QUEUE_RO_ENTRY(queue_nr_zones, "nr_zones"); 621 QUEUE_LIM_RO_ENTRY(queue_max_open_zones, "max_open_zones"); 622 QUEUE_LIM_RO_ENTRY(queue_max_active_zones, "max_active_zones"); 623 624 QUEUE_RW_ENTRY(queue_nomerges, "nomerges"); 625 QUEUE_LIM_RW_ENTRY(queue_iostats_passthrough, "iostats_passthrough"); 626 QUEUE_RW_ENTRY(queue_rq_affinity, "rq_affinity"); 627 QUEUE_RW_ENTRY(queue_poll, "io_poll"); 628 QUEUE_RW_ENTRY(queue_poll_delay, "io_poll_delay"); 629 QUEUE_LIM_RW_ENTRY(queue_wc, "write_cache"); 630 QUEUE_LIM_RO_ENTRY(queue_fua, "fua"); 631 QUEUE_LIM_RO_ENTRY(queue_dax, "dax"); 632 QUEUE_RW_ENTRY(queue_io_timeout, "io_timeout"); 633 QUEUE_LIM_RO_ENTRY(queue_virt_boundary_mask, "virt_boundary_mask"); 634 QUEUE_LIM_RO_ENTRY(queue_dma_alignment, "dma_alignment"); 635 636 /* legacy alias for logical_block_size: */ 637 static struct queue_sysfs_entry queue_hw_sector_size_entry = { 638 .attr = {.name = "hw_sector_size", .mode = 0444 }, 639 .show_limit = queue_logical_block_size_show, 640 }; 641 642 QUEUE_LIM_RW_ENTRY(queue_rotational, "rotational"); 643 QUEUE_LIM_RW_ENTRY(queue_iostats, "iostats"); 644 QUEUE_LIM_RW_ENTRY(queue_add_random, "add_random"); 645 QUEUE_LIM_RW_ENTRY(queue_stable_writes, "stable_writes"); 646 647 #ifdef CONFIG_BLK_WBT 648 static ssize_t queue_var_store64(s64 *var, const char *page) 649 { 650 int err; 651 s64 v; 652 653 err = kstrtos64(page, 10, &v); 654 if (err < 0) 655 return err; 656 657 *var = v; 658 return 0; 659 } 660 661 static ssize_t queue_wb_lat_show(struct gendisk *disk, char *page) 662 { 663 ssize_t ret; 664 struct request_queue *q = disk->queue; 665 666 mutex_lock(&disk->rqos_state_mutex); 667 if (!wbt_rq_qos(q)) { 668 ret = -EINVAL; 669 goto out; 670 } 671 672 if (wbt_disabled(q)) { 673 ret = sysfs_emit(page, "0\n"); 674 goto out; 675 } 676 677 ret = sysfs_emit(page, "%llu\n", div_u64(wbt_get_min_lat(q), 1000)); 678 out: 679 mutex_unlock(&disk->rqos_state_mutex); 680 return ret; 681 } 682 683 static ssize_t queue_wb_lat_store(struct gendisk *disk, const char *page, 684 size_t count) 685 { 686 ssize_t ret; 687 s64 val; 688 689 ret = queue_var_store64(&val, page); 690 if (ret < 0) 691 return ret; 692 if (val < -1) 693 return -EINVAL; 694 695 ret = wbt_set_lat(disk, val); 696 return ret ? ret : count; 697 } 698 699 QUEUE_RW_ENTRY(queue_wb_lat, "wbt_lat_usec"); 700 #endif 701 702 /* Common attributes for bio-based and request-based queues. */ 703 static struct attribute *queue_attrs[] = { 704 /* 705 * Attributes which are protected with q->limits_lock. 706 */ 707 &queue_max_hw_sectors_entry.attr, 708 &queue_max_sectors_entry.attr, 709 &queue_max_segments_entry.attr, 710 &queue_max_discard_segments_entry.attr, 711 &queue_max_integrity_segments_entry.attr, 712 &queue_max_segment_size_entry.attr, 713 &queue_max_write_streams_entry.attr, 714 &queue_write_stream_granularity_entry.attr, 715 &queue_hw_sector_size_entry.attr, 716 &queue_logical_block_size_entry.attr, 717 &queue_physical_block_size_entry.attr, 718 &queue_chunk_sectors_entry.attr, 719 &queue_io_min_entry.attr, 720 &queue_io_opt_entry.attr, 721 &queue_discard_granularity_entry.attr, 722 &queue_max_discard_sectors_entry.attr, 723 &queue_max_hw_discard_sectors_entry.attr, 724 &queue_atomic_write_max_sectors_entry.attr, 725 &queue_atomic_write_boundary_sectors_entry.attr, 726 &queue_atomic_write_unit_min_entry.attr, 727 &queue_atomic_write_unit_max_entry.attr, 728 &queue_max_write_zeroes_sectors_entry.attr, 729 &queue_max_hw_wzeroes_unmap_sectors_entry.attr, 730 &queue_max_wzeroes_unmap_sectors_entry.attr, 731 &queue_max_zone_append_sectors_entry.attr, 732 &queue_zone_write_granularity_entry.attr, 733 &queue_rotational_entry.attr, 734 &queue_zoned_entry.attr, 735 &queue_max_open_zones_entry.attr, 736 &queue_max_active_zones_entry.attr, 737 &queue_iostats_passthrough_entry.attr, 738 &queue_iostats_entry.attr, 739 &queue_stable_writes_entry.attr, 740 &queue_add_random_entry.attr, 741 &queue_wc_entry.attr, 742 &queue_fua_entry.attr, 743 &queue_dax_entry.attr, 744 &queue_virt_boundary_mask_entry.attr, 745 &queue_dma_alignment_entry.attr, 746 &queue_ra_entry.attr, 747 748 /* 749 * Attributes which don't require locking. 750 */ 751 &queue_discard_zeroes_data_entry.attr, 752 &queue_write_same_max_entry.attr, 753 &queue_nr_zones_entry.attr, 754 &queue_nomerges_entry.attr, 755 &queue_poll_entry.attr, 756 &queue_poll_delay_entry.attr, 757 758 NULL, 759 }; 760 761 /* Request-based queue attributes that are not relevant for bio-based queues. */ 762 static struct attribute *blk_mq_queue_attrs[] = { 763 /* 764 * Attributes which require some form of locking other than 765 * q->sysfs_lock. 766 */ 767 &elv_iosched_entry.attr, 768 &queue_requests_entry.attr, 769 &queue_async_depth_entry.attr, 770 #ifdef CONFIG_BLK_WBT 771 &queue_wb_lat_entry.attr, 772 #endif 773 /* 774 * Attributes which don't require locking. 775 */ 776 &queue_rq_affinity_entry.attr, 777 &queue_io_timeout_entry.attr, 778 779 NULL, 780 }; 781 782 static umode_t queue_attr_visible(struct kobject *kobj, struct attribute *attr, 783 int n) 784 { 785 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 786 struct request_queue *q = disk->queue; 787 788 if ((attr == &queue_max_open_zones_entry.attr || 789 attr == &queue_max_active_zones_entry.attr) && 790 !blk_queue_is_zoned(q)) 791 return 0; 792 793 return attr->mode; 794 } 795 796 static umode_t blk_mq_queue_attr_visible(struct kobject *kobj, 797 struct attribute *attr, int n) 798 { 799 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 800 struct request_queue *q = disk->queue; 801 802 if (!queue_is_mq(q)) 803 return 0; 804 805 if (attr == &queue_io_timeout_entry.attr && !q->mq_ops->timeout) 806 return 0; 807 808 return attr->mode; 809 } 810 811 static struct attribute_group queue_attr_group = { 812 .attrs = queue_attrs, 813 .is_visible = queue_attr_visible, 814 }; 815 816 static struct attribute_group blk_mq_queue_attr_group = { 817 .attrs = blk_mq_queue_attrs, 818 .is_visible = blk_mq_queue_attr_visible, 819 }; 820 821 #define to_queue(atr) container_of((atr), struct queue_sysfs_entry, attr) 822 823 static ssize_t 824 queue_attr_show(struct kobject *kobj, struct attribute *attr, char *page) 825 { 826 struct queue_sysfs_entry *entry = to_queue(attr); 827 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 828 829 if (!entry->show && !entry->show_limit) 830 return -EIO; 831 832 if (entry->show_limit) { 833 ssize_t res; 834 835 mutex_lock(&disk->queue->limits_lock); 836 res = entry->show_limit(disk, page); 837 mutex_unlock(&disk->queue->limits_lock); 838 return res; 839 } 840 841 return entry->show(disk, page); 842 } 843 844 static ssize_t 845 queue_attr_store(struct kobject *kobj, struct attribute *attr, 846 const char *page, size_t length) 847 { 848 struct queue_sysfs_entry *entry = to_queue(attr); 849 struct gendisk *disk = container_of(kobj, struct gendisk, queue_kobj); 850 struct request_queue *q = disk->queue; 851 852 if (!entry->store_limit && !entry->store) 853 return -EIO; 854 855 if (entry->store_limit) { 856 ssize_t res; 857 858 struct queue_limits lim = queue_limits_start_update(q); 859 860 res = entry->store_limit(disk, page, length, &lim); 861 if (res < 0) { 862 queue_limits_cancel_update(q); 863 return res; 864 } 865 866 res = queue_limits_commit_update_frozen(q, &lim); 867 if (res) 868 return res; 869 return length; 870 } 871 872 return entry->store(disk, page, length); 873 } 874 875 static const struct sysfs_ops queue_sysfs_ops = { 876 .show = queue_attr_show, 877 .store = queue_attr_store, 878 }; 879 880 static const struct attribute_group *blk_queue_attr_groups[] = { 881 &queue_attr_group, 882 &blk_mq_queue_attr_group, 883 NULL 884 }; 885 886 static void blk_queue_release(struct kobject *kobj) 887 { 888 /* nothing to do here, all data is associated with the parent gendisk */ 889 } 890 891 const struct kobj_type blk_queue_ktype = { 892 .default_groups = blk_queue_attr_groups, 893 .sysfs_ops = &queue_sysfs_ops, 894 .release = blk_queue_release, 895 }; 896 897 static void blk_debugfs_remove(struct gendisk *disk) 898 { 899 struct request_queue *q = disk->queue; 900 901 blk_debugfs_lock_nomemsave(q); 902 blk_trace_shutdown(q); 903 debugfs_remove_recursive(q->debugfs_dir); 904 q->debugfs_dir = NULL; 905 q->sched_debugfs_dir = NULL; 906 q->rqos_debugfs_dir = NULL; 907 blk_debugfs_unlock_nomemrestore(q); 908 } 909 910 /** 911 * blk_register_queue - register a block layer queue with sysfs 912 * @disk: Disk of which the request queue should be registered with sysfs. 913 */ 914 int blk_register_queue(struct gendisk *disk) 915 { 916 struct request_queue *q = disk->queue; 917 unsigned int memflags; 918 int ret; 919 920 ret = kobject_add(&disk->queue_kobj, &disk_to_dev(disk)->kobj, "queue"); 921 if (ret < 0) 922 return ret; 923 924 if (queue_is_mq(q)) { 925 ret = blk_mq_sysfs_register(disk); 926 if (ret) 927 goto out_del_queue_kobj; 928 } 929 mutex_lock(&q->sysfs_lock); 930 931 memflags = blk_debugfs_lock(q); 932 q->debugfs_dir = debugfs_create_dir(disk->disk_name, blk_debugfs_root); 933 if (queue_is_mq(q)) 934 blk_mq_debugfs_register(q); 935 blk_debugfs_unlock(q, memflags); 936 937 ret = disk_register_independent_access_ranges(disk); 938 if (ret) 939 goto out_debugfs_remove; 940 941 ret = blk_crypto_sysfs_register(disk); 942 if (ret) 943 goto out_unregister_ia_ranges; 944 945 if (queue_is_mq(q)) 946 elevator_set_default(q); 947 948 blk_queue_flag_set(QUEUE_FLAG_REGISTERED, q); 949 wbt_init_enable_default(disk); 950 951 /* Now everything is ready and send out KOBJ_ADD uevent */ 952 kobject_uevent(&disk->queue_kobj, KOBJ_ADD); 953 if (q->elevator) 954 kobject_uevent(&q->elevator->kobj, KOBJ_ADD); 955 mutex_unlock(&q->sysfs_lock); 956 957 /* 958 * SCSI probing may synchronously create and destroy a lot of 959 * request_queues for non-existent devices. Shutting down a fully 960 * functional queue takes measureable wallclock time as RCU grace 961 * periods are involved. To avoid excessive latency in these 962 * cases, a request_queue starts out in a degraded mode which is 963 * faster to shut down and is made fully functional here as 964 * request_queues for non-existent devices never get registered. 965 */ 966 blk_queue_flag_set(QUEUE_FLAG_INIT_DONE, q); 967 percpu_ref_switch_to_percpu(&q->q_usage_counter); 968 969 return ret; 970 971 out_unregister_ia_ranges: 972 disk_unregister_independent_access_ranges(disk); 973 out_debugfs_remove: 974 blk_debugfs_remove(disk); 975 mutex_unlock(&q->sysfs_lock); 976 if (queue_is_mq(q)) 977 blk_mq_sysfs_unregister(disk); 978 out_del_queue_kobj: 979 kobject_del(&disk->queue_kobj); 980 return ret; 981 } 982 983 /** 984 * blk_unregister_queue - counterpart of blk_register_queue() 985 * @disk: Disk of which the request queue should be unregistered from sysfs. 986 * 987 * Note: the caller is responsible for guaranteeing that this function is called 988 * after blk_register_queue() has finished. 989 */ 990 void blk_unregister_queue(struct gendisk *disk) 991 { 992 struct request_queue *q = disk->queue; 993 994 if (WARN_ON(!q)) 995 return; 996 997 /* Return early if disk->queue was never registered. */ 998 if (!blk_queue_registered(q)) 999 return; 1000 1001 /* 1002 * Since sysfs_remove_dir() prevents adding new directory entries 1003 * before removal of existing entries starts, protect against 1004 * concurrent elv_iosched_store() calls. 1005 */ 1006 mutex_lock(&q->sysfs_lock); 1007 blk_queue_flag_clear(QUEUE_FLAG_REGISTERED, q); 1008 mutex_unlock(&q->sysfs_lock); 1009 1010 /* 1011 * Remove the sysfs attributes before unregistering the queue data 1012 * structures that can be modified through sysfs. 1013 */ 1014 if (queue_is_mq(q)) 1015 blk_mq_sysfs_unregister(disk); 1016 blk_crypto_sysfs_unregister(disk); 1017 1018 mutex_lock(&q->sysfs_lock); 1019 disk_unregister_independent_access_ranges(disk); 1020 mutex_unlock(&q->sysfs_lock); 1021 1022 /* Now that we've deleted all child objects, we can delete the queue. */ 1023 kobject_uevent(&disk->queue_kobj, KOBJ_REMOVE); 1024 kobject_del(&disk->queue_kobj); 1025 1026 if (queue_is_mq(q)) 1027 elevator_set_none(q); 1028 1029 blk_debugfs_remove(disk); 1030 } 1031