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-wbt.h" 20 #include "blk-cgroup.h" 21 #include "blk-throttle.h" 22 23 struct queue_sysfs_entry { 24 struct attribute attr; 25 ssize_t (*show)(struct request_queue *, char *); 26 ssize_t (*store)(struct request_queue *, const char *, size_t); 27 }; 28 29 static ssize_t 30 queue_var_show(unsigned long var, char *page) 31 { 32 return sprintf(page, "%lu\n", var); 33 } 34 35 static ssize_t 36 queue_var_store(unsigned long *var, const char *page, size_t count) 37 { 38 int err; 39 unsigned long v; 40 41 err = kstrtoul(page, 10, &v); 42 if (err || v > UINT_MAX) 43 return -EINVAL; 44 45 *var = v; 46 47 return count; 48 } 49 50 static ssize_t queue_var_store64(s64 *var, const char *page) 51 { 52 int err; 53 s64 v; 54 55 err = kstrtos64(page, 10, &v); 56 if (err < 0) 57 return err; 58 59 *var = v; 60 return 0; 61 } 62 63 static ssize_t queue_requests_show(struct request_queue *q, char *page) 64 { 65 return queue_var_show(q->nr_requests, page); 66 } 67 68 static ssize_t 69 queue_requests_store(struct request_queue *q, const char *page, size_t count) 70 { 71 unsigned long nr; 72 int ret, err; 73 74 if (!queue_is_mq(q)) 75 return -EINVAL; 76 77 ret = queue_var_store(&nr, page, count); 78 if (ret < 0) 79 return ret; 80 81 if (nr < BLKDEV_MIN_RQ) 82 nr = BLKDEV_MIN_RQ; 83 84 err = blk_mq_update_nr_requests(q, nr); 85 if (err) 86 return err; 87 88 return ret; 89 } 90 91 static ssize_t queue_ra_show(struct request_queue *q, char *page) 92 { 93 unsigned long ra_kb; 94 95 if (!q->disk) 96 return -EINVAL; 97 ra_kb = q->disk->bdi->ra_pages << (PAGE_SHIFT - 10); 98 return queue_var_show(ra_kb, page); 99 } 100 101 static ssize_t 102 queue_ra_store(struct request_queue *q, const char *page, size_t count) 103 { 104 unsigned long ra_kb; 105 ssize_t ret; 106 107 if (!q->disk) 108 return -EINVAL; 109 ret = queue_var_store(&ra_kb, page, count); 110 if (ret < 0) 111 return ret; 112 q->disk->bdi->ra_pages = ra_kb >> (PAGE_SHIFT - 10); 113 return ret; 114 } 115 116 static ssize_t queue_max_sectors_show(struct request_queue *q, char *page) 117 { 118 int max_sectors_kb = queue_max_sectors(q) >> 1; 119 120 return queue_var_show(max_sectors_kb, page); 121 } 122 123 static ssize_t queue_max_segments_show(struct request_queue *q, char *page) 124 { 125 return queue_var_show(queue_max_segments(q), page); 126 } 127 128 static ssize_t queue_max_discard_segments_show(struct request_queue *q, 129 char *page) 130 { 131 return queue_var_show(queue_max_discard_segments(q), page); 132 } 133 134 static ssize_t queue_max_integrity_segments_show(struct request_queue *q, char *page) 135 { 136 return queue_var_show(q->limits.max_integrity_segments, page); 137 } 138 139 static ssize_t queue_max_segment_size_show(struct request_queue *q, char *page) 140 { 141 return queue_var_show(queue_max_segment_size(q), page); 142 } 143 144 static ssize_t queue_logical_block_size_show(struct request_queue *q, char *page) 145 { 146 return queue_var_show(queue_logical_block_size(q), page); 147 } 148 149 static ssize_t queue_physical_block_size_show(struct request_queue *q, char *page) 150 { 151 return queue_var_show(queue_physical_block_size(q), page); 152 } 153 154 static ssize_t queue_chunk_sectors_show(struct request_queue *q, char *page) 155 { 156 return queue_var_show(q->limits.chunk_sectors, page); 157 } 158 159 static ssize_t queue_io_min_show(struct request_queue *q, char *page) 160 { 161 return queue_var_show(queue_io_min(q), page); 162 } 163 164 static ssize_t queue_io_opt_show(struct request_queue *q, char *page) 165 { 166 return queue_var_show(queue_io_opt(q), page); 167 } 168 169 static ssize_t queue_discard_granularity_show(struct request_queue *q, char *page) 170 { 171 return queue_var_show(q->limits.discard_granularity, page); 172 } 173 174 static ssize_t queue_discard_max_hw_show(struct request_queue *q, char *page) 175 { 176 177 return sprintf(page, "%llu\n", 178 (unsigned long long)q->limits.max_hw_discard_sectors << 9); 179 } 180 181 static ssize_t queue_discard_max_show(struct request_queue *q, char *page) 182 { 183 return sprintf(page, "%llu\n", 184 (unsigned long long)q->limits.max_discard_sectors << 9); 185 } 186 187 static ssize_t queue_discard_max_store(struct request_queue *q, 188 const char *page, size_t count) 189 { 190 unsigned long max_discard; 191 ssize_t ret = queue_var_store(&max_discard, page, count); 192 193 if (ret < 0) 194 return ret; 195 196 if (max_discard & (q->limits.discard_granularity - 1)) 197 return -EINVAL; 198 199 max_discard >>= 9; 200 if (max_discard > UINT_MAX) 201 return -EINVAL; 202 203 if (max_discard > q->limits.max_hw_discard_sectors) 204 max_discard = q->limits.max_hw_discard_sectors; 205 206 q->limits.max_discard_sectors = max_discard; 207 return ret; 208 } 209 210 static ssize_t queue_discard_zeroes_data_show(struct request_queue *q, char *page) 211 { 212 return queue_var_show(0, page); 213 } 214 215 static ssize_t queue_write_same_max_show(struct request_queue *q, char *page) 216 { 217 return queue_var_show(0, page); 218 } 219 220 static ssize_t queue_write_zeroes_max_show(struct request_queue *q, char *page) 221 { 222 return sprintf(page, "%llu\n", 223 (unsigned long long)q->limits.max_write_zeroes_sectors << 9); 224 } 225 226 static ssize_t queue_zone_write_granularity_show(struct request_queue *q, 227 char *page) 228 { 229 return queue_var_show(queue_zone_write_granularity(q), page); 230 } 231 232 static ssize_t queue_zone_append_max_show(struct request_queue *q, char *page) 233 { 234 unsigned long long max_sectors = q->limits.max_zone_append_sectors; 235 236 return sprintf(page, "%llu\n", max_sectors << SECTOR_SHIFT); 237 } 238 239 static ssize_t 240 queue_max_sectors_store(struct request_queue *q, const char *page, size_t count) 241 { 242 unsigned long max_sectors_kb, 243 max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1, 244 page_kb = 1 << (PAGE_SHIFT - 10); 245 ssize_t ret = queue_var_store(&max_sectors_kb, page, count); 246 247 if (ret < 0) 248 return ret; 249 250 max_hw_sectors_kb = min_not_zero(max_hw_sectors_kb, (unsigned long) 251 q->limits.max_dev_sectors >> 1); 252 253 if (max_sectors_kb > max_hw_sectors_kb || max_sectors_kb < page_kb) 254 return -EINVAL; 255 256 spin_lock_irq(&q->queue_lock); 257 q->limits.max_sectors = max_sectors_kb << 1; 258 if (q->disk) 259 q->disk->bdi->io_pages = max_sectors_kb >> (PAGE_SHIFT - 10); 260 spin_unlock_irq(&q->queue_lock); 261 262 return ret; 263 } 264 265 static ssize_t queue_max_hw_sectors_show(struct request_queue *q, char *page) 266 { 267 int max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1; 268 269 return queue_var_show(max_hw_sectors_kb, page); 270 } 271 272 static ssize_t queue_virt_boundary_mask_show(struct request_queue *q, char *page) 273 { 274 return queue_var_show(q->limits.virt_boundary_mask, page); 275 } 276 277 static ssize_t queue_dma_alignment_show(struct request_queue *q, char *page) 278 { 279 return queue_var_show(queue_dma_alignment(q), page); 280 } 281 282 #define QUEUE_SYSFS_BIT_FNS(name, flag, neg) \ 283 static ssize_t \ 284 queue_##name##_show(struct request_queue *q, char *page) \ 285 { \ 286 int bit; \ 287 bit = test_bit(QUEUE_FLAG_##flag, &q->queue_flags); \ 288 return queue_var_show(neg ? !bit : bit, page); \ 289 } \ 290 static ssize_t \ 291 queue_##name##_store(struct request_queue *q, const char *page, size_t count) \ 292 { \ 293 unsigned long val; \ 294 ssize_t ret; \ 295 ret = queue_var_store(&val, page, count); \ 296 if (ret < 0) \ 297 return ret; \ 298 if (neg) \ 299 val = !val; \ 300 \ 301 if (val) \ 302 blk_queue_flag_set(QUEUE_FLAG_##flag, q); \ 303 else \ 304 blk_queue_flag_clear(QUEUE_FLAG_##flag, q); \ 305 return ret; \ 306 } 307 308 QUEUE_SYSFS_BIT_FNS(nonrot, NONROT, 1); 309 QUEUE_SYSFS_BIT_FNS(random, ADD_RANDOM, 0); 310 QUEUE_SYSFS_BIT_FNS(iostats, IO_STAT, 0); 311 QUEUE_SYSFS_BIT_FNS(stable_writes, STABLE_WRITES, 0); 312 #undef QUEUE_SYSFS_BIT_FNS 313 314 static ssize_t queue_zoned_show(struct request_queue *q, char *page) 315 { 316 switch (blk_queue_zoned_model(q)) { 317 case BLK_ZONED_HA: 318 return sprintf(page, "host-aware\n"); 319 case BLK_ZONED_HM: 320 return sprintf(page, "host-managed\n"); 321 default: 322 return sprintf(page, "none\n"); 323 } 324 } 325 326 static ssize_t queue_nr_zones_show(struct request_queue *q, char *page) 327 { 328 return queue_var_show(disk_nr_zones(q->disk), page); 329 } 330 331 static ssize_t queue_max_open_zones_show(struct request_queue *q, char *page) 332 { 333 return queue_var_show(bdev_max_open_zones(q->disk->part0), page); 334 } 335 336 static ssize_t queue_max_active_zones_show(struct request_queue *q, char *page) 337 { 338 return queue_var_show(bdev_max_active_zones(q->disk->part0), page); 339 } 340 341 static ssize_t queue_nomerges_show(struct request_queue *q, char *page) 342 { 343 return queue_var_show((blk_queue_nomerges(q) << 1) | 344 blk_queue_noxmerges(q), page); 345 } 346 347 static ssize_t queue_nomerges_store(struct request_queue *q, const char *page, 348 size_t count) 349 { 350 unsigned long nm; 351 ssize_t ret = queue_var_store(&nm, page, count); 352 353 if (ret < 0) 354 return ret; 355 356 blk_queue_flag_clear(QUEUE_FLAG_NOMERGES, q); 357 blk_queue_flag_clear(QUEUE_FLAG_NOXMERGES, q); 358 if (nm == 2) 359 blk_queue_flag_set(QUEUE_FLAG_NOMERGES, q); 360 else if (nm) 361 blk_queue_flag_set(QUEUE_FLAG_NOXMERGES, q); 362 363 return ret; 364 } 365 366 static ssize_t queue_rq_affinity_show(struct request_queue *q, char *page) 367 { 368 bool set = test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags); 369 bool force = test_bit(QUEUE_FLAG_SAME_FORCE, &q->queue_flags); 370 371 return queue_var_show(set << force, page); 372 } 373 374 static ssize_t 375 queue_rq_affinity_store(struct request_queue *q, const char *page, size_t count) 376 { 377 ssize_t ret = -EINVAL; 378 #ifdef CONFIG_SMP 379 unsigned long val; 380 381 ret = queue_var_store(&val, page, count); 382 if (ret < 0) 383 return ret; 384 385 if (val == 2) { 386 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q); 387 blk_queue_flag_set(QUEUE_FLAG_SAME_FORCE, q); 388 } else if (val == 1) { 389 blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q); 390 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q); 391 } else if (val == 0) { 392 blk_queue_flag_clear(QUEUE_FLAG_SAME_COMP, q); 393 blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q); 394 } 395 #endif 396 return ret; 397 } 398 399 static ssize_t queue_poll_delay_show(struct request_queue *q, char *page) 400 { 401 int val; 402 403 if (q->poll_nsec == BLK_MQ_POLL_CLASSIC) 404 val = BLK_MQ_POLL_CLASSIC; 405 else 406 val = q->poll_nsec / 1000; 407 408 return sprintf(page, "%d\n", val); 409 } 410 411 static ssize_t queue_poll_delay_store(struct request_queue *q, const char *page, 412 size_t count) 413 { 414 int err, val; 415 416 if (!q->mq_ops || !q->mq_ops->poll) 417 return -EINVAL; 418 419 err = kstrtoint(page, 10, &val); 420 if (err < 0) 421 return err; 422 423 if (val == BLK_MQ_POLL_CLASSIC) 424 q->poll_nsec = BLK_MQ_POLL_CLASSIC; 425 else if (val >= 0) 426 q->poll_nsec = val * 1000; 427 else 428 return -EINVAL; 429 430 return count; 431 } 432 433 static ssize_t queue_poll_show(struct request_queue *q, char *page) 434 { 435 return queue_var_show(test_bit(QUEUE_FLAG_POLL, &q->queue_flags), page); 436 } 437 438 static ssize_t queue_poll_store(struct request_queue *q, const char *page, 439 size_t count) 440 { 441 if (!test_bit(QUEUE_FLAG_POLL, &q->queue_flags)) 442 return -EINVAL; 443 pr_info_ratelimited("writes to the poll attribute are ignored.\n"); 444 pr_info_ratelimited("please use driver specific parameters instead.\n"); 445 return count; 446 } 447 448 static ssize_t queue_io_timeout_show(struct request_queue *q, char *page) 449 { 450 return sprintf(page, "%u\n", jiffies_to_msecs(q->rq_timeout)); 451 } 452 453 static ssize_t queue_io_timeout_store(struct request_queue *q, const char *page, 454 size_t count) 455 { 456 unsigned int val; 457 int err; 458 459 err = kstrtou32(page, 10, &val); 460 if (err || val == 0) 461 return -EINVAL; 462 463 blk_queue_rq_timeout(q, msecs_to_jiffies(val)); 464 465 return count; 466 } 467 468 static ssize_t queue_wb_lat_show(struct request_queue *q, char *page) 469 { 470 if (!wbt_rq_qos(q)) 471 return -EINVAL; 472 473 return sprintf(page, "%llu\n", div_u64(wbt_get_min_lat(q), 1000)); 474 } 475 476 static ssize_t queue_wb_lat_store(struct request_queue *q, const char *page, 477 size_t count) 478 { 479 struct rq_qos *rqos; 480 ssize_t ret; 481 s64 val; 482 483 ret = queue_var_store64(&val, page); 484 if (ret < 0) 485 return ret; 486 if (val < -1) 487 return -EINVAL; 488 489 rqos = wbt_rq_qos(q); 490 if (!rqos) { 491 ret = wbt_init(q); 492 if (ret) 493 return ret; 494 } 495 496 if (val == -1) 497 val = wbt_default_latency_nsec(q); 498 else if (val >= 0) 499 val *= 1000ULL; 500 501 if (wbt_get_min_lat(q) == val) 502 return count; 503 504 /* 505 * Ensure that the queue is idled, in case the latency update 506 * ends up either enabling or disabling wbt completely. We can't 507 * have IO inflight if that happens. 508 */ 509 blk_mq_freeze_queue(q); 510 blk_mq_quiesce_queue(q); 511 512 wbt_set_min_lat(q, val); 513 514 blk_mq_unquiesce_queue(q); 515 blk_mq_unfreeze_queue(q); 516 517 return count; 518 } 519 520 static ssize_t queue_wc_show(struct request_queue *q, char *page) 521 { 522 if (test_bit(QUEUE_FLAG_WC, &q->queue_flags)) 523 return sprintf(page, "write back\n"); 524 525 return sprintf(page, "write through\n"); 526 } 527 528 static ssize_t queue_wc_store(struct request_queue *q, const char *page, 529 size_t count) 530 { 531 int set = -1; 532 533 if (!strncmp(page, "write back", 10)) 534 set = 1; 535 else if (!strncmp(page, "write through", 13) || 536 !strncmp(page, "none", 4)) 537 set = 0; 538 539 if (set == -1) 540 return -EINVAL; 541 542 if (set) 543 blk_queue_flag_set(QUEUE_FLAG_WC, q); 544 else 545 blk_queue_flag_clear(QUEUE_FLAG_WC, q); 546 547 return count; 548 } 549 550 static ssize_t queue_fua_show(struct request_queue *q, char *page) 551 { 552 return sprintf(page, "%u\n", test_bit(QUEUE_FLAG_FUA, &q->queue_flags)); 553 } 554 555 static ssize_t queue_dax_show(struct request_queue *q, char *page) 556 { 557 return queue_var_show(blk_queue_dax(q), page); 558 } 559 560 #define QUEUE_RO_ENTRY(_prefix, _name) \ 561 static struct queue_sysfs_entry _prefix##_entry = { \ 562 .attr = { .name = _name, .mode = 0444 }, \ 563 .show = _prefix##_show, \ 564 }; 565 566 #define QUEUE_RW_ENTRY(_prefix, _name) \ 567 static struct queue_sysfs_entry _prefix##_entry = { \ 568 .attr = { .name = _name, .mode = 0644 }, \ 569 .show = _prefix##_show, \ 570 .store = _prefix##_store, \ 571 }; 572 573 QUEUE_RW_ENTRY(queue_requests, "nr_requests"); 574 QUEUE_RW_ENTRY(queue_ra, "read_ahead_kb"); 575 QUEUE_RW_ENTRY(queue_max_sectors, "max_sectors_kb"); 576 QUEUE_RO_ENTRY(queue_max_hw_sectors, "max_hw_sectors_kb"); 577 QUEUE_RO_ENTRY(queue_max_segments, "max_segments"); 578 QUEUE_RO_ENTRY(queue_max_integrity_segments, "max_integrity_segments"); 579 QUEUE_RO_ENTRY(queue_max_segment_size, "max_segment_size"); 580 QUEUE_RW_ENTRY(elv_iosched, "scheduler"); 581 582 QUEUE_RO_ENTRY(queue_logical_block_size, "logical_block_size"); 583 QUEUE_RO_ENTRY(queue_physical_block_size, "physical_block_size"); 584 QUEUE_RO_ENTRY(queue_chunk_sectors, "chunk_sectors"); 585 QUEUE_RO_ENTRY(queue_io_min, "minimum_io_size"); 586 QUEUE_RO_ENTRY(queue_io_opt, "optimal_io_size"); 587 588 QUEUE_RO_ENTRY(queue_max_discard_segments, "max_discard_segments"); 589 QUEUE_RO_ENTRY(queue_discard_granularity, "discard_granularity"); 590 QUEUE_RO_ENTRY(queue_discard_max_hw, "discard_max_hw_bytes"); 591 QUEUE_RW_ENTRY(queue_discard_max, "discard_max_bytes"); 592 QUEUE_RO_ENTRY(queue_discard_zeroes_data, "discard_zeroes_data"); 593 594 QUEUE_RO_ENTRY(queue_write_same_max, "write_same_max_bytes"); 595 QUEUE_RO_ENTRY(queue_write_zeroes_max, "write_zeroes_max_bytes"); 596 QUEUE_RO_ENTRY(queue_zone_append_max, "zone_append_max_bytes"); 597 QUEUE_RO_ENTRY(queue_zone_write_granularity, "zone_write_granularity"); 598 599 QUEUE_RO_ENTRY(queue_zoned, "zoned"); 600 QUEUE_RO_ENTRY(queue_nr_zones, "nr_zones"); 601 QUEUE_RO_ENTRY(queue_max_open_zones, "max_open_zones"); 602 QUEUE_RO_ENTRY(queue_max_active_zones, "max_active_zones"); 603 604 QUEUE_RW_ENTRY(queue_nomerges, "nomerges"); 605 QUEUE_RW_ENTRY(queue_rq_affinity, "rq_affinity"); 606 QUEUE_RW_ENTRY(queue_poll, "io_poll"); 607 QUEUE_RW_ENTRY(queue_poll_delay, "io_poll_delay"); 608 QUEUE_RW_ENTRY(queue_wc, "write_cache"); 609 QUEUE_RO_ENTRY(queue_fua, "fua"); 610 QUEUE_RO_ENTRY(queue_dax, "dax"); 611 QUEUE_RW_ENTRY(queue_io_timeout, "io_timeout"); 612 QUEUE_RW_ENTRY(queue_wb_lat, "wbt_lat_usec"); 613 QUEUE_RO_ENTRY(queue_virt_boundary_mask, "virt_boundary_mask"); 614 QUEUE_RO_ENTRY(queue_dma_alignment, "dma_alignment"); 615 616 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW 617 QUEUE_RW_ENTRY(blk_throtl_sample_time, "throttle_sample_time"); 618 #endif 619 620 /* legacy alias for logical_block_size: */ 621 static struct queue_sysfs_entry queue_hw_sector_size_entry = { 622 .attr = {.name = "hw_sector_size", .mode = 0444 }, 623 .show = queue_logical_block_size_show, 624 }; 625 626 QUEUE_RW_ENTRY(queue_nonrot, "rotational"); 627 QUEUE_RW_ENTRY(queue_iostats, "iostats"); 628 QUEUE_RW_ENTRY(queue_random, "add_random"); 629 QUEUE_RW_ENTRY(queue_stable_writes, "stable_writes"); 630 631 static struct attribute *queue_attrs[] = { 632 &queue_requests_entry.attr, 633 &queue_ra_entry.attr, 634 &queue_max_hw_sectors_entry.attr, 635 &queue_max_sectors_entry.attr, 636 &queue_max_segments_entry.attr, 637 &queue_max_discard_segments_entry.attr, 638 &queue_max_integrity_segments_entry.attr, 639 &queue_max_segment_size_entry.attr, 640 &elv_iosched_entry.attr, 641 &queue_hw_sector_size_entry.attr, 642 &queue_logical_block_size_entry.attr, 643 &queue_physical_block_size_entry.attr, 644 &queue_chunk_sectors_entry.attr, 645 &queue_io_min_entry.attr, 646 &queue_io_opt_entry.attr, 647 &queue_discard_granularity_entry.attr, 648 &queue_discard_max_entry.attr, 649 &queue_discard_max_hw_entry.attr, 650 &queue_discard_zeroes_data_entry.attr, 651 &queue_write_same_max_entry.attr, 652 &queue_write_zeroes_max_entry.attr, 653 &queue_zone_append_max_entry.attr, 654 &queue_zone_write_granularity_entry.attr, 655 &queue_nonrot_entry.attr, 656 &queue_zoned_entry.attr, 657 &queue_nr_zones_entry.attr, 658 &queue_max_open_zones_entry.attr, 659 &queue_max_active_zones_entry.attr, 660 &queue_nomerges_entry.attr, 661 &queue_rq_affinity_entry.attr, 662 &queue_iostats_entry.attr, 663 &queue_stable_writes_entry.attr, 664 &queue_random_entry.attr, 665 &queue_poll_entry.attr, 666 &queue_wc_entry.attr, 667 &queue_fua_entry.attr, 668 &queue_dax_entry.attr, 669 &queue_wb_lat_entry.attr, 670 &queue_poll_delay_entry.attr, 671 &queue_io_timeout_entry.attr, 672 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW 673 &blk_throtl_sample_time_entry.attr, 674 #endif 675 &queue_virt_boundary_mask_entry.attr, 676 &queue_dma_alignment_entry.attr, 677 NULL, 678 }; 679 680 static umode_t queue_attr_visible(struct kobject *kobj, struct attribute *attr, 681 int n) 682 { 683 struct request_queue *q = 684 container_of(kobj, struct request_queue, kobj); 685 686 if (attr == &queue_io_timeout_entry.attr && 687 (!q->mq_ops || !q->mq_ops->timeout)) 688 return 0; 689 690 if ((attr == &queue_max_open_zones_entry.attr || 691 attr == &queue_max_active_zones_entry.attr) && 692 !blk_queue_is_zoned(q)) 693 return 0; 694 695 return attr->mode; 696 } 697 698 static struct attribute_group queue_attr_group = { 699 .attrs = queue_attrs, 700 .is_visible = queue_attr_visible, 701 }; 702 703 704 #define to_queue(atr) container_of((atr), struct queue_sysfs_entry, attr) 705 706 static ssize_t 707 queue_attr_show(struct kobject *kobj, struct attribute *attr, char *page) 708 { 709 struct queue_sysfs_entry *entry = to_queue(attr); 710 struct request_queue *q = 711 container_of(kobj, struct request_queue, kobj); 712 ssize_t res; 713 714 if (!entry->show) 715 return -EIO; 716 mutex_lock(&q->sysfs_lock); 717 res = entry->show(q, page); 718 mutex_unlock(&q->sysfs_lock); 719 return res; 720 } 721 722 static ssize_t 723 queue_attr_store(struct kobject *kobj, struct attribute *attr, 724 const char *page, size_t length) 725 { 726 struct queue_sysfs_entry *entry = to_queue(attr); 727 struct request_queue *q; 728 ssize_t res; 729 730 if (!entry->store) 731 return -EIO; 732 733 q = container_of(kobj, struct request_queue, kobj); 734 mutex_lock(&q->sysfs_lock); 735 res = entry->store(q, page, length); 736 mutex_unlock(&q->sysfs_lock); 737 return res; 738 } 739 740 static void blk_free_queue_rcu(struct rcu_head *rcu_head) 741 { 742 struct request_queue *q = container_of(rcu_head, struct request_queue, 743 rcu_head); 744 745 kmem_cache_free(blk_get_queue_kmem_cache(blk_queue_has_srcu(q)), q); 746 } 747 748 /** 749 * blk_release_queue - releases all allocated resources of the request_queue 750 * @kobj: pointer to a kobject, whose container is a request_queue 751 * 752 * This function releases all allocated resources of the request queue. 753 * 754 * The struct request_queue refcount is incremented with blk_get_queue() and 755 * decremented with blk_put_queue(). Once the refcount reaches 0 this function 756 * is called. 757 * 758 * Drivers exist which depend on the release of the request_queue to be 759 * synchronous, it should not be deferred. 760 * 761 * Context: can sleep 762 */ 763 static void blk_release_queue(struct kobject *kobj) 764 { 765 struct request_queue *q = 766 container_of(kobj, struct request_queue, kobj); 767 768 might_sleep(); 769 770 percpu_ref_exit(&q->q_usage_counter); 771 772 if (q->poll_stat) 773 blk_stat_remove_callback(q, q->poll_cb); 774 blk_stat_free_callback(q->poll_cb); 775 776 blk_free_queue_stats(q->stats); 777 kfree(q->poll_stat); 778 779 if (queue_is_mq(q)) 780 blk_mq_release(q); 781 782 if (blk_queue_has_srcu(q)) 783 cleanup_srcu_struct(q->srcu); 784 785 ida_free(&blk_queue_ida, q->id); 786 call_rcu(&q->rcu_head, blk_free_queue_rcu); 787 } 788 789 static const struct sysfs_ops queue_sysfs_ops = { 790 .show = queue_attr_show, 791 .store = queue_attr_store, 792 }; 793 794 static const struct attribute_group *blk_queue_attr_groups[] = { 795 &queue_attr_group, 796 NULL 797 }; 798 799 struct kobj_type blk_queue_ktype = { 800 .default_groups = blk_queue_attr_groups, 801 .sysfs_ops = &queue_sysfs_ops, 802 .release = blk_release_queue, 803 }; 804 805 /** 806 * blk_register_queue - register a block layer queue with sysfs 807 * @disk: Disk of which the request queue should be registered with sysfs. 808 */ 809 int blk_register_queue(struct gendisk *disk) 810 { 811 struct request_queue *q = disk->queue; 812 int ret; 813 814 mutex_lock(&q->sysfs_dir_lock); 815 816 ret = kobject_add(&q->kobj, &disk_to_dev(disk)->kobj, "queue"); 817 if (ret < 0) 818 goto unlock; 819 820 if (queue_is_mq(q)) 821 blk_mq_sysfs_register(disk); 822 mutex_lock(&q->sysfs_lock); 823 824 mutex_lock(&q->debugfs_mutex); 825 q->debugfs_dir = debugfs_create_dir(kobject_name(q->kobj.parent), 826 blk_debugfs_root); 827 if (queue_is_mq(q)) 828 blk_mq_debugfs_register(q); 829 mutex_unlock(&q->debugfs_mutex); 830 831 ret = disk_register_independent_access_ranges(disk); 832 if (ret) 833 goto put_dev; 834 835 if (q->elevator) { 836 ret = elv_register_queue(q, false); 837 if (ret) 838 goto put_dev; 839 } 840 841 ret = blk_crypto_sysfs_register(q); 842 if (ret) 843 goto put_dev; 844 845 blk_queue_flag_set(QUEUE_FLAG_REGISTERED, q); 846 wbt_enable_default(q); 847 blk_throtl_register(disk); 848 849 /* Now everything is ready and send out KOBJ_ADD uevent */ 850 kobject_uevent(&q->kobj, KOBJ_ADD); 851 if (q->elevator) 852 kobject_uevent(&q->elevator->kobj, KOBJ_ADD); 853 mutex_unlock(&q->sysfs_lock); 854 855 unlock: 856 mutex_unlock(&q->sysfs_dir_lock); 857 858 /* 859 * SCSI probing may synchronously create and destroy a lot of 860 * request_queues for non-existent devices. Shutting down a fully 861 * functional queue takes measureable wallclock time as RCU grace 862 * periods are involved. To avoid excessive latency in these 863 * cases, a request_queue starts out in a degraded mode which is 864 * faster to shut down and is made fully functional here as 865 * request_queues for non-existent devices never get registered. 866 */ 867 if (!blk_queue_init_done(q)) { 868 blk_queue_flag_set(QUEUE_FLAG_INIT_DONE, q); 869 percpu_ref_switch_to_percpu(&q->q_usage_counter); 870 } 871 872 return ret; 873 874 put_dev: 875 elv_unregister_queue(q); 876 disk_unregister_independent_access_ranges(disk); 877 mutex_unlock(&q->sysfs_lock); 878 mutex_unlock(&q->sysfs_dir_lock); 879 kobject_del(&q->kobj); 880 881 return ret; 882 } 883 884 /** 885 * blk_unregister_queue - counterpart of blk_register_queue() 886 * @disk: Disk of which the request queue should be unregistered from sysfs. 887 * 888 * Note: the caller is responsible for guaranteeing that this function is called 889 * after blk_register_queue() has finished. 890 */ 891 void blk_unregister_queue(struct gendisk *disk) 892 { 893 struct request_queue *q = disk->queue; 894 895 if (WARN_ON(!q)) 896 return; 897 898 /* Return early if disk->queue was never registered. */ 899 if (!blk_queue_registered(q)) 900 return; 901 902 /* 903 * Since sysfs_remove_dir() prevents adding new directory entries 904 * before removal of existing entries starts, protect against 905 * concurrent elv_iosched_store() calls. 906 */ 907 mutex_lock(&q->sysfs_lock); 908 blk_queue_flag_clear(QUEUE_FLAG_REGISTERED, q); 909 mutex_unlock(&q->sysfs_lock); 910 911 mutex_lock(&q->sysfs_dir_lock); 912 /* 913 * Remove the sysfs attributes before unregistering the queue data 914 * structures that can be modified through sysfs. 915 */ 916 if (queue_is_mq(q)) 917 blk_mq_sysfs_unregister(disk); 918 blk_crypto_sysfs_unregister(q); 919 920 mutex_lock(&q->sysfs_lock); 921 elv_unregister_queue(q); 922 disk_unregister_independent_access_ranges(disk); 923 mutex_unlock(&q->sysfs_lock); 924 925 /* Now that we've deleted all child objects, we can delete the queue. */ 926 kobject_uevent(&q->kobj, KOBJ_REMOVE); 927 kobject_del(&q->kobj); 928 mutex_unlock(&q->sysfs_dir_lock); 929 930 mutex_lock(&q->debugfs_mutex); 931 blk_trace_shutdown(q); 932 debugfs_remove_recursive(q->debugfs_dir); 933 q->debugfs_dir = NULL; 934 q->sched_debugfs_dir = NULL; 935 q->rqos_debugfs_dir = NULL; 936 mutex_unlock(&q->debugfs_mutex); 937 } 938