1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Functions related to setting various queue properties from drivers 4 */ 5 #include <linux/kernel.h> 6 #include <linux/module.h> 7 #include <linux/init.h> 8 #include <linux/bio.h> 9 #include <linux/blkdev.h> 10 #include <linux/pagemap.h> 11 #include <linux/backing-dev-defs.h> 12 #include <linux/gcd.h> 13 #include <linux/lcm.h> 14 #include <linux/jiffies.h> 15 #include <linux/gfp.h> 16 #include <linux/dma-mapping.h> 17 18 #include "blk.h" 19 #include "blk-rq-qos.h" 20 #include "blk-wbt.h" 21 22 void blk_queue_rq_timeout(struct request_queue *q, unsigned int timeout) 23 { 24 q->rq_timeout = timeout; 25 } 26 EXPORT_SYMBOL_GPL(blk_queue_rq_timeout); 27 28 /** 29 * blk_set_default_limits - reset limits to default values 30 * @lim: the queue_limits structure to reset 31 * 32 * Description: 33 * Returns a queue_limit struct to its default state. 34 */ 35 void blk_set_default_limits(struct queue_limits *lim) 36 { 37 lim->max_segments = BLK_MAX_SEGMENTS; 38 lim->max_discard_segments = 1; 39 lim->max_integrity_segments = 0; 40 lim->seg_boundary_mask = BLK_SEG_BOUNDARY_MASK; 41 lim->virt_boundary_mask = 0; 42 lim->max_segment_size = BLK_MAX_SEGMENT_SIZE; 43 lim->max_sectors = lim->max_hw_sectors = BLK_SAFE_MAX_SECTORS; 44 lim->max_user_sectors = lim->max_dev_sectors = 0; 45 lim->chunk_sectors = 0; 46 lim->max_write_zeroes_sectors = 0; 47 lim->max_zone_append_sectors = 0; 48 lim->max_discard_sectors = 0; 49 lim->max_hw_discard_sectors = 0; 50 lim->max_secure_erase_sectors = 0; 51 lim->discard_granularity = 512; 52 lim->discard_alignment = 0; 53 lim->discard_misaligned = 0; 54 lim->logical_block_size = lim->physical_block_size = lim->io_min = 512; 55 lim->bounce = BLK_BOUNCE_NONE; 56 lim->alignment_offset = 0; 57 lim->io_opt = 0; 58 lim->misaligned = 0; 59 lim->zoned = false; 60 lim->zone_write_granularity = 0; 61 lim->dma_alignment = 511; 62 } 63 64 /** 65 * blk_set_stacking_limits - set default limits for stacking devices 66 * @lim: the queue_limits structure to reset 67 * 68 * Description: 69 * Returns a queue_limit struct to its default state. Should be used 70 * by stacking drivers like DM that have no internal limits. 71 */ 72 void blk_set_stacking_limits(struct queue_limits *lim) 73 { 74 blk_set_default_limits(lim); 75 76 /* Inherit limits from component devices */ 77 lim->max_segments = USHRT_MAX; 78 lim->max_discard_segments = USHRT_MAX; 79 lim->max_hw_sectors = UINT_MAX; 80 lim->max_segment_size = UINT_MAX; 81 lim->max_sectors = UINT_MAX; 82 lim->max_dev_sectors = UINT_MAX; 83 lim->max_write_zeroes_sectors = UINT_MAX; 84 lim->max_zone_append_sectors = UINT_MAX; 85 } 86 EXPORT_SYMBOL(blk_set_stacking_limits); 87 88 /** 89 * blk_queue_bounce_limit - set bounce buffer limit for queue 90 * @q: the request queue for the device 91 * @bounce: bounce limit to enforce 92 * 93 * Description: 94 * Force bouncing for ISA DMA ranges or highmem. 95 * 96 * DEPRECATED, don't use in new code. 97 **/ 98 void blk_queue_bounce_limit(struct request_queue *q, enum blk_bounce bounce) 99 { 100 q->limits.bounce = bounce; 101 } 102 EXPORT_SYMBOL(blk_queue_bounce_limit); 103 104 /** 105 * blk_queue_max_hw_sectors - set max sectors for a request for this queue 106 * @q: the request queue for the device 107 * @max_hw_sectors: max hardware sectors in the usual 512b unit 108 * 109 * Description: 110 * Enables a low level driver to set a hard upper limit, 111 * max_hw_sectors, on the size of requests. max_hw_sectors is set by 112 * the device driver based upon the capabilities of the I/O 113 * controller. 114 * 115 * max_dev_sectors is a hard limit imposed by the storage device for 116 * READ/WRITE requests. It is set by the disk driver. 117 * 118 * max_sectors is a soft limit imposed by the block layer for 119 * filesystem type requests. This value can be overridden on a 120 * per-device basis in /sys/block/<device>/queue/max_sectors_kb. 121 * The soft limit can not exceed max_hw_sectors. 122 **/ 123 void blk_queue_max_hw_sectors(struct request_queue *q, unsigned int max_hw_sectors) 124 { 125 struct queue_limits *limits = &q->limits; 126 unsigned int max_sectors; 127 128 if ((max_hw_sectors << 9) < PAGE_SIZE) { 129 max_hw_sectors = 1 << (PAGE_SHIFT - 9); 130 pr_info("%s: set to minimum %u\n", __func__, max_hw_sectors); 131 } 132 133 max_hw_sectors = round_down(max_hw_sectors, 134 limits->logical_block_size >> SECTOR_SHIFT); 135 limits->max_hw_sectors = max_hw_sectors; 136 137 max_sectors = min_not_zero(max_hw_sectors, limits->max_dev_sectors); 138 139 if (limits->max_user_sectors) 140 max_sectors = min(max_sectors, limits->max_user_sectors); 141 else 142 max_sectors = min(max_sectors, BLK_DEF_MAX_SECTORS_CAP); 143 144 max_sectors = round_down(max_sectors, 145 limits->logical_block_size >> SECTOR_SHIFT); 146 limits->max_sectors = max_sectors; 147 148 if (!q->disk) 149 return; 150 q->disk->bdi->io_pages = max_sectors >> (PAGE_SHIFT - 9); 151 } 152 EXPORT_SYMBOL(blk_queue_max_hw_sectors); 153 154 /** 155 * blk_queue_chunk_sectors - set size of the chunk for this queue 156 * @q: the request queue for the device 157 * @chunk_sectors: chunk sectors in the usual 512b unit 158 * 159 * Description: 160 * If a driver doesn't want IOs to cross a given chunk size, it can set 161 * this limit and prevent merging across chunks. Note that the block layer 162 * must accept a page worth of data at any offset. So if the crossing of 163 * chunks is a hard limitation in the driver, it must still be prepared 164 * to split single page bios. 165 **/ 166 void blk_queue_chunk_sectors(struct request_queue *q, unsigned int chunk_sectors) 167 { 168 q->limits.chunk_sectors = chunk_sectors; 169 } 170 EXPORT_SYMBOL(blk_queue_chunk_sectors); 171 172 /** 173 * blk_queue_max_discard_sectors - set max sectors for a single discard 174 * @q: the request queue for the device 175 * @max_discard_sectors: maximum number of sectors to discard 176 **/ 177 void blk_queue_max_discard_sectors(struct request_queue *q, 178 unsigned int max_discard_sectors) 179 { 180 q->limits.max_hw_discard_sectors = max_discard_sectors; 181 q->limits.max_discard_sectors = max_discard_sectors; 182 } 183 EXPORT_SYMBOL(blk_queue_max_discard_sectors); 184 185 /** 186 * blk_queue_max_secure_erase_sectors - set max sectors for a secure erase 187 * @q: the request queue for the device 188 * @max_sectors: maximum number of sectors to secure_erase 189 **/ 190 void blk_queue_max_secure_erase_sectors(struct request_queue *q, 191 unsigned int max_sectors) 192 { 193 q->limits.max_secure_erase_sectors = max_sectors; 194 } 195 EXPORT_SYMBOL(blk_queue_max_secure_erase_sectors); 196 197 /** 198 * blk_queue_max_write_zeroes_sectors - set max sectors for a single 199 * write zeroes 200 * @q: the request queue for the device 201 * @max_write_zeroes_sectors: maximum number of sectors to write per command 202 **/ 203 void blk_queue_max_write_zeroes_sectors(struct request_queue *q, 204 unsigned int max_write_zeroes_sectors) 205 { 206 q->limits.max_write_zeroes_sectors = max_write_zeroes_sectors; 207 } 208 EXPORT_SYMBOL(blk_queue_max_write_zeroes_sectors); 209 210 /** 211 * blk_queue_max_zone_append_sectors - set max sectors for a single zone append 212 * @q: the request queue for the device 213 * @max_zone_append_sectors: maximum number of sectors to write per command 214 **/ 215 void blk_queue_max_zone_append_sectors(struct request_queue *q, 216 unsigned int max_zone_append_sectors) 217 { 218 unsigned int max_sectors; 219 220 if (WARN_ON(!blk_queue_is_zoned(q))) 221 return; 222 223 max_sectors = min(q->limits.max_hw_sectors, max_zone_append_sectors); 224 max_sectors = min(q->limits.chunk_sectors, max_sectors); 225 226 /* 227 * Signal eventual driver bugs resulting in the max_zone_append sectors limit 228 * being 0 due to a 0 argument, the chunk_sectors limit (zone size) not set, 229 * or the max_hw_sectors limit not set. 230 */ 231 WARN_ON(!max_sectors); 232 233 q->limits.max_zone_append_sectors = max_sectors; 234 } 235 EXPORT_SYMBOL_GPL(blk_queue_max_zone_append_sectors); 236 237 /** 238 * blk_queue_max_segments - set max hw segments for a request for this queue 239 * @q: the request queue for the device 240 * @max_segments: max number of segments 241 * 242 * Description: 243 * Enables a low level driver to set an upper limit on the number of 244 * hw data segments in a request. 245 **/ 246 void blk_queue_max_segments(struct request_queue *q, unsigned short max_segments) 247 { 248 if (!max_segments) { 249 max_segments = 1; 250 pr_info("%s: set to minimum %u\n", __func__, max_segments); 251 } 252 253 q->limits.max_segments = max_segments; 254 } 255 EXPORT_SYMBOL(blk_queue_max_segments); 256 257 /** 258 * blk_queue_max_discard_segments - set max segments for discard requests 259 * @q: the request queue for the device 260 * @max_segments: max number of segments 261 * 262 * Description: 263 * Enables a low level driver to set an upper limit on the number of 264 * segments in a discard request. 265 **/ 266 void blk_queue_max_discard_segments(struct request_queue *q, 267 unsigned short max_segments) 268 { 269 q->limits.max_discard_segments = max_segments; 270 } 271 EXPORT_SYMBOL_GPL(blk_queue_max_discard_segments); 272 273 /** 274 * blk_queue_max_segment_size - set max segment size for blk_rq_map_sg 275 * @q: the request queue for the device 276 * @max_size: max size of segment in bytes 277 * 278 * Description: 279 * Enables a low level driver to set an upper limit on the size of a 280 * coalesced segment 281 **/ 282 void blk_queue_max_segment_size(struct request_queue *q, unsigned int max_size) 283 { 284 if (max_size < PAGE_SIZE) { 285 max_size = PAGE_SIZE; 286 pr_info("%s: set to minimum %u\n", __func__, max_size); 287 } 288 289 /* see blk_queue_virt_boundary() for the explanation */ 290 WARN_ON_ONCE(q->limits.virt_boundary_mask); 291 292 q->limits.max_segment_size = max_size; 293 } 294 EXPORT_SYMBOL(blk_queue_max_segment_size); 295 296 /** 297 * blk_queue_logical_block_size - set logical block size for the queue 298 * @q: the request queue for the device 299 * @size: the logical block size, in bytes 300 * 301 * Description: 302 * This should be set to the lowest possible block size that the 303 * storage device can address. The default of 512 covers most 304 * hardware. 305 **/ 306 void blk_queue_logical_block_size(struct request_queue *q, unsigned int size) 307 { 308 struct queue_limits *limits = &q->limits; 309 310 limits->logical_block_size = size; 311 312 if (limits->discard_granularity < limits->logical_block_size) 313 limits->discard_granularity = limits->logical_block_size; 314 315 if (limits->physical_block_size < size) 316 limits->physical_block_size = size; 317 318 if (limits->io_min < limits->physical_block_size) 319 limits->io_min = limits->physical_block_size; 320 321 limits->max_hw_sectors = 322 round_down(limits->max_hw_sectors, size >> SECTOR_SHIFT); 323 limits->max_sectors = 324 round_down(limits->max_sectors, size >> SECTOR_SHIFT); 325 } 326 EXPORT_SYMBOL(blk_queue_logical_block_size); 327 328 /** 329 * blk_queue_physical_block_size - set physical block size for the queue 330 * @q: the request queue for the device 331 * @size: the physical block size, in bytes 332 * 333 * Description: 334 * This should be set to the lowest possible sector size that the 335 * hardware can operate on without reverting to read-modify-write 336 * operations. 337 */ 338 void blk_queue_physical_block_size(struct request_queue *q, unsigned int size) 339 { 340 q->limits.physical_block_size = size; 341 342 if (q->limits.physical_block_size < q->limits.logical_block_size) 343 q->limits.physical_block_size = q->limits.logical_block_size; 344 345 if (q->limits.discard_granularity < q->limits.physical_block_size) 346 q->limits.discard_granularity = q->limits.physical_block_size; 347 348 if (q->limits.io_min < q->limits.physical_block_size) 349 q->limits.io_min = q->limits.physical_block_size; 350 } 351 EXPORT_SYMBOL(blk_queue_physical_block_size); 352 353 /** 354 * blk_queue_zone_write_granularity - set zone write granularity for the queue 355 * @q: the request queue for the zoned device 356 * @size: the zone write granularity size, in bytes 357 * 358 * Description: 359 * This should be set to the lowest possible size allowing to write in 360 * sequential zones of a zoned block device. 361 */ 362 void blk_queue_zone_write_granularity(struct request_queue *q, 363 unsigned int size) 364 { 365 if (WARN_ON_ONCE(!blk_queue_is_zoned(q))) 366 return; 367 368 q->limits.zone_write_granularity = size; 369 370 if (q->limits.zone_write_granularity < q->limits.logical_block_size) 371 q->limits.zone_write_granularity = q->limits.logical_block_size; 372 } 373 EXPORT_SYMBOL_GPL(blk_queue_zone_write_granularity); 374 375 /** 376 * blk_queue_alignment_offset - set physical block alignment offset 377 * @q: the request queue for the device 378 * @offset: alignment offset in bytes 379 * 380 * Description: 381 * Some devices are naturally misaligned to compensate for things like 382 * the legacy DOS partition table 63-sector offset. Low-level drivers 383 * should call this function for devices whose first sector is not 384 * naturally aligned. 385 */ 386 void blk_queue_alignment_offset(struct request_queue *q, unsigned int offset) 387 { 388 q->limits.alignment_offset = 389 offset & (q->limits.physical_block_size - 1); 390 q->limits.misaligned = 0; 391 } 392 EXPORT_SYMBOL(blk_queue_alignment_offset); 393 394 void disk_update_readahead(struct gendisk *disk) 395 { 396 struct request_queue *q = disk->queue; 397 398 /* 399 * For read-ahead of large files to be effective, we need to read ahead 400 * at least twice the optimal I/O size. 401 */ 402 disk->bdi->ra_pages = 403 max(queue_io_opt(q) * 2 / PAGE_SIZE, VM_READAHEAD_PAGES); 404 disk->bdi->io_pages = queue_max_sectors(q) >> (PAGE_SHIFT - 9); 405 } 406 EXPORT_SYMBOL_GPL(disk_update_readahead); 407 408 /** 409 * blk_limits_io_min - set minimum request size for a device 410 * @limits: the queue limits 411 * @min: smallest I/O size in bytes 412 * 413 * Description: 414 * Some devices have an internal block size bigger than the reported 415 * hardware sector size. This function can be used to signal the 416 * smallest I/O the device can perform without incurring a performance 417 * penalty. 418 */ 419 void blk_limits_io_min(struct queue_limits *limits, unsigned int min) 420 { 421 limits->io_min = min; 422 423 if (limits->io_min < limits->logical_block_size) 424 limits->io_min = limits->logical_block_size; 425 426 if (limits->io_min < limits->physical_block_size) 427 limits->io_min = limits->physical_block_size; 428 } 429 EXPORT_SYMBOL(blk_limits_io_min); 430 431 /** 432 * blk_queue_io_min - set minimum request size for the queue 433 * @q: the request queue for the device 434 * @min: smallest I/O size in bytes 435 * 436 * Description: 437 * Storage devices may report a granularity or preferred minimum I/O 438 * size which is the smallest request the device can perform without 439 * incurring a performance penalty. For disk drives this is often the 440 * physical block size. For RAID arrays it is often the stripe chunk 441 * size. A properly aligned multiple of minimum_io_size is the 442 * preferred request size for workloads where a high number of I/O 443 * operations is desired. 444 */ 445 void blk_queue_io_min(struct request_queue *q, unsigned int min) 446 { 447 blk_limits_io_min(&q->limits, min); 448 } 449 EXPORT_SYMBOL(blk_queue_io_min); 450 451 /** 452 * blk_limits_io_opt - set optimal request size for a device 453 * @limits: the queue limits 454 * @opt: smallest I/O size in bytes 455 * 456 * Description: 457 * Storage devices may report an optimal I/O size, which is the 458 * device's preferred unit for sustained I/O. This is rarely reported 459 * for disk drives. For RAID arrays it is usually the stripe width or 460 * the internal track size. A properly aligned multiple of 461 * optimal_io_size is the preferred request size for workloads where 462 * sustained throughput is desired. 463 */ 464 void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt) 465 { 466 limits->io_opt = opt; 467 } 468 EXPORT_SYMBOL(blk_limits_io_opt); 469 470 /** 471 * blk_queue_io_opt - set optimal request size for the queue 472 * @q: the request queue for the device 473 * @opt: optimal request size in bytes 474 * 475 * Description: 476 * Storage devices may report an optimal I/O size, which is the 477 * device's preferred unit for sustained I/O. This is rarely reported 478 * for disk drives. For RAID arrays it is usually the stripe width or 479 * the internal track size. A properly aligned multiple of 480 * optimal_io_size is the preferred request size for workloads where 481 * sustained throughput is desired. 482 */ 483 void blk_queue_io_opt(struct request_queue *q, unsigned int opt) 484 { 485 blk_limits_io_opt(&q->limits, opt); 486 if (!q->disk) 487 return; 488 q->disk->bdi->ra_pages = 489 max(queue_io_opt(q) * 2 / PAGE_SIZE, VM_READAHEAD_PAGES); 490 } 491 EXPORT_SYMBOL(blk_queue_io_opt); 492 493 static int queue_limit_alignment_offset(const struct queue_limits *lim, 494 sector_t sector) 495 { 496 unsigned int granularity = max(lim->physical_block_size, lim->io_min); 497 unsigned int alignment = sector_div(sector, granularity >> SECTOR_SHIFT) 498 << SECTOR_SHIFT; 499 500 return (granularity + lim->alignment_offset - alignment) % granularity; 501 } 502 503 static unsigned int queue_limit_discard_alignment( 504 const struct queue_limits *lim, sector_t sector) 505 { 506 unsigned int alignment, granularity, offset; 507 508 if (!lim->max_discard_sectors) 509 return 0; 510 511 /* Why are these in bytes, not sectors? */ 512 alignment = lim->discard_alignment >> SECTOR_SHIFT; 513 granularity = lim->discard_granularity >> SECTOR_SHIFT; 514 if (!granularity) 515 return 0; 516 517 /* Offset of the partition start in 'granularity' sectors */ 518 offset = sector_div(sector, granularity); 519 520 /* And why do we do this modulus *again* in blkdev_issue_discard()? */ 521 offset = (granularity + alignment - offset) % granularity; 522 523 /* Turn it back into bytes, gaah */ 524 return offset << SECTOR_SHIFT; 525 } 526 527 static unsigned int blk_round_down_sectors(unsigned int sectors, unsigned int lbs) 528 { 529 sectors = round_down(sectors, lbs >> SECTOR_SHIFT); 530 if (sectors < PAGE_SIZE >> SECTOR_SHIFT) 531 sectors = PAGE_SIZE >> SECTOR_SHIFT; 532 return sectors; 533 } 534 535 /** 536 * blk_stack_limits - adjust queue_limits for stacked devices 537 * @t: the stacking driver limits (top device) 538 * @b: the underlying queue limits (bottom, component device) 539 * @start: first data sector within component device 540 * 541 * Description: 542 * This function is used by stacking drivers like MD and DM to ensure 543 * that all component devices have compatible block sizes and 544 * alignments. The stacking driver must provide a queue_limits 545 * struct (top) and then iteratively call the stacking function for 546 * all component (bottom) devices. The stacking function will 547 * attempt to combine the values and ensure proper alignment. 548 * 549 * Returns 0 if the top and bottom queue_limits are compatible. The 550 * top device's block sizes and alignment offsets may be adjusted to 551 * ensure alignment with the bottom device. If no compatible sizes 552 * and alignments exist, -1 is returned and the resulting top 553 * queue_limits will have the misaligned flag set to indicate that 554 * the alignment_offset is undefined. 555 */ 556 int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, 557 sector_t start) 558 { 559 unsigned int top, bottom, alignment, ret = 0; 560 561 t->max_sectors = min_not_zero(t->max_sectors, b->max_sectors); 562 t->max_hw_sectors = min_not_zero(t->max_hw_sectors, b->max_hw_sectors); 563 t->max_dev_sectors = min_not_zero(t->max_dev_sectors, b->max_dev_sectors); 564 t->max_write_zeroes_sectors = min(t->max_write_zeroes_sectors, 565 b->max_write_zeroes_sectors); 566 t->max_zone_append_sectors = min(t->max_zone_append_sectors, 567 b->max_zone_append_sectors); 568 t->bounce = max(t->bounce, b->bounce); 569 570 t->seg_boundary_mask = min_not_zero(t->seg_boundary_mask, 571 b->seg_boundary_mask); 572 t->virt_boundary_mask = min_not_zero(t->virt_boundary_mask, 573 b->virt_boundary_mask); 574 575 t->max_segments = min_not_zero(t->max_segments, b->max_segments); 576 t->max_discard_segments = min_not_zero(t->max_discard_segments, 577 b->max_discard_segments); 578 t->max_integrity_segments = min_not_zero(t->max_integrity_segments, 579 b->max_integrity_segments); 580 581 t->max_segment_size = min_not_zero(t->max_segment_size, 582 b->max_segment_size); 583 584 t->misaligned |= b->misaligned; 585 586 alignment = queue_limit_alignment_offset(b, start); 587 588 /* Bottom device has different alignment. Check that it is 589 * compatible with the current top alignment. 590 */ 591 if (t->alignment_offset != alignment) { 592 593 top = max(t->physical_block_size, t->io_min) 594 + t->alignment_offset; 595 bottom = max(b->physical_block_size, b->io_min) + alignment; 596 597 /* Verify that top and bottom intervals line up */ 598 if (max(top, bottom) % min(top, bottom)) { 599 t->misaligned = 1; 600 ret = -1; 601 } 602 } 603 604 t->logical_block_size = max(t->logical_block_size, 605 b->logical_block_size); 606 607 t->physical_block_size = max(t->physical_block_size, 608 b->physical_block_size); 609 610 t->io_min = max(t->io_min, b->io_min); 611 t->io_opt = lcm_not_zero(t->io_opt, b->io_opt); 612 t->dma_alignment = max(t->dma_alignment, b->dma_alignment); 613 614 /* Set non-power-of-2 compatible chunk_sectors boundary */ 615 if (b->chunk_sectors) 616 t->chunk_sectors = gcd(t->chunk_sectors, b->chunk_sectors); 617 618 /* Physical block size a multiple of the logical block size? */ 619 if (t->physical_block_size & (t->logical_block_size - 1)) { 620 t->physical_block_size = t->logical_block_size; 621 t->misaligned = 1; 622 ret = -1; 623 } 624 625 /* Minimum I/O a multiple of the physical block size? */ 626 if (t->io_min & (t->physical_block_size - 1)) { 627 t->io_min = t->physical_block_size; 628 t->misaligned = 1; 629 ret = -1; 630 } 631 632 /* Optimal I/O a multiple of the physical block size? */ 633 if (t->io_opt & (t->physical_block_size - 1)) { 634 t->io_opt = 0; 635 t->misaligned = 1; 636 ret = -1; 637 } 638 639 /* chunk_sectors a multiple of the physical block size? */ 640 if ((t->chunk_sectors << 9) & (t->physical_block_size - 1)) { 641 t->chunk_sectors = 0; 642 t->misaligned = 1; 643 ret = -1; 644 } 645 646 t->raid_partial_stripes_expensive = 647 max(t->raid_partial_stripes_expensive, 648 b->raid_partial_stripes_expensive); 649 650 /* Find lowest common alignment_offset */ 651 t->alignment_offset = lcm_not_zero(t->alignment_offset, alignment) 652 % max(t->physical_block_size, t->io_min); 653 654 /* Verify that new alignment_offset is on a logical block boundary */ 655 if (t->alignment_offset & (t->logical_block_size - 1)) { 656 t->misaligned = 1; 657 ret = -1; 658 } 659 660 t->max_sectors = blk_round_down_sectors(t->max_sectors, t->logical_block_size); 661 t->max_hw_sectors = blk_round_down_sectors(t->max_hw_sectors, t->logical_block_size); 662 t->max_dev_sectors = blk_round_down_sectors(t->max_dev_sectors, t->logical_block_size); 663 664 /* Discard alignment and granularity */ 665 if (b->discard_granularity) { 666 alignment = queue_limit_discard_alignment(b, start); 667 668 if (t->discard_granularity != 0 && 669 t->discard_alignment != alignment) { 670 top = t->discard_granularity + t->discard_alignment; 671 bottom = b->discard_granularity + alignment; 672 673 /* Verify that top and bottom intervals line up */ 674 if ((max(top, bottom) % min(top, bottom)) != 0) 675 t->discard_misaligned = 1; 676 } 677 678 t->max_discard_sectors = min_not_zero(t->max_discard_sectors, 679 b->max_discard_sectors); 680 t->max_hw_discard_sectors = min_not_zero(t->max_hw_discard_sectors, 681 b->max_hw_discard_sectors); 682 t->discard_granularity = max(t->discard_granularity, 683 b->discard_granularity); 684 t->discard_alignment = lcm_not_zero(t->discard_alignment, alignment) % 685 t->discard_granularity; 686 } 687 t->max_secure_erase_sectors = min_not_zero(t->max_secure_erase_sectors, 688 b->max_secure_erase_sectors); 689 t->zone_write_granularity = max(t->zone_write_granularity, 690 b->zone_write_granularity); 691 t->zoned = max(t->zoned, b->zoned); 692 return ret; 693 } 694 EXPORT_SYMBOL(blk_stack_limits); 695 696 /** 697 * disk_stack_limits - adjust queue limits for stacked drivers 698 * @disk: MD/DM gendisk (top) 699 * @bdev: the underlying block device (bottom) 700 * @offset: offset to beginning of data within component device 701 * 702 * Description: 703 * Merges the limits for a top level gendisk and a bottom level 704 * block_device. 705 */ 706 void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, 707 sector_t offset) 708 { 709 struct request_queue *t = disk->queue; 710 711 if (blk_stack_limits(&t->limits, &bdev_get_queue(bdev)->limits, 712 get_start_sect(bdev) + (offset >> 9)) < 0) 713 pr_notice("%s: Warning: Device %pg is misaligned\n", 714 disk->disk_name, bdev); 715 716 disk_update_readahead(disk); 717 } 718 EXPORT_SYMBOL(disk_stack_limits); 719 720 /** 721 * blk_queue_update_dma_pad - update pad mask 722 * @q: the request queue for the device 723 * @mask: pad mask 724 * 725 * Update dma pad mask. 726 * 727 * Appending pad buffer to a request modifies the last entry of a 728 * scatter list such that it includes the pad buffer. 729 **/ 730 void blk_queue_update_dma_pad(struct request_queue *q, unsigned int mask) 731 { 732 if (mask > q->dma_pad_mask) 733 q->dma_pad_mask = mask; 734 } 735 EXPORT_SYMBOL(blk_queue_update_dma_pad); 736 737 /** 738 * blk_queue_segment_boundary - set boundary rules for segment merging 739 * @q: the request queue for the device 740 * @mask: the memory boundary mask 741 **/ 742 void blk_queue_segment_boundary(struct request_queue *q, unsigned long mask) 743 { 744 if (mask < PAGE_SIZE - 1) { 745 mask = PAGE_SIZE - 1; 746 pr_info("%s: set to minimum %lx\n", __func__, mask); 747 } 748 749 q->limits.seg_boundary_mask = mask; 750 } 751 EXPORT_SYMBOL(blk_queue_segment_boundary); 752 753 /** 754 * blk_queue_virt_boundary - set boundary rules for bio merging 755 * @q: the request queue for the device 756 * @mask: the memory boundary mask 757 **/ 758 void blk_queue_virt_boundary(struct request_queue *q, unsigned long mask) 759 { 760 q->limits.virt_boundary_mask = mask; 761 762 /* 763 * Devices that require a virtual boundary do not support scatter/gather 764 * I/O natively, but instead require a descriptor list entry for each 765 * page (which might not be idential to the Linux PAGE_SIZE). Because 766 * of that they are not limited by our notion of "segment size". 767 */ 768 if (mask) 769 q->limits.max_segment_size = UINT_MAX; 770 } 771 EXPORT_SYMBOL(blk_queue_virt_boundary); 772 773 /** 774 * blk_queue_dma_alignment - set dma length and memory alignment 775 * @q: the request queue for the device 776 * @mask: alignment mask 777 * 778 * description: 779 * set required memory and length alignment for direct dma transactions. 780 * this is used when building direct io requests for the queue. 781 * 782 **/ 783 void blk_queue_dma_alignment(struct request_queue *q, int mask) 784 { 785 q->limits.dma_alignment = mask; 786 } 787 EXPORT_SYMBOL(blk_queue_dma_alignment); 788 789 /** 790 * blk_queue_update_dma_alignment - update dma length and memory alignment 791 * @q: the request queue for the device 792 * @mask: alignment mask 793 * 794 * description: 795 * update required memory and length alignment for direct dma transactions. 796 * If the requested alignment is larger than the current alignment, then 797 * the current queue alignment is updated to the new value, otherwise it 798 * is left alone. The design of this is to allow multiple objects 799 * (driver, device, transport etc) to set their respective 800 * alignments without having them interfere. 801 * 802 **/ 803 void blk_queue_update_dma_alignment(struct request_queue *q, int mask) 804 { 805 BUG_ON(mask > PAGE_SIZE); 806 807 if (mask > q->limits.dma_alignment) 808 q->limits.dma_alignment = mask; 809 } 810 EXPORT_SYMBOL(blk_queue_update_dma_alignment); 811 812 /** 813 * blk_set_queue_depth - tell the block layer about the device queue depth 814 * @q: the request queue for the device 815 * @depth: queue depth 816 * 817 */ 818 void blk_set_queue_depth(struct request_queue *q, unsigned int depth) 819 { 820 q->queue_depth = depth; 821 rq_qos_queue_depth_changed(q); 822 } 823 EXPORT_SYMBOL(blk_set_queue_depth); 824 825 /** 826 * blk_queue_write_cache - configure queue's write cache 827 * @q: the request queue for the device 828 * @wc: write back cache on or off 829 * @fua: device supports FUA writes, if true 830 * 831 * Tell the block layer about the write cache of @q. 832 */ 833 void blk_queue_write_cache(struct request_queue *q, bool wc, bool fua) 834 { 835 if (wc) { 836 blk_queue_flag_set(QUEUE_FLAG_HW_WC, q); 837 blk_queue_flag_set(QUEUE_FLAG_WC, q); 838 } else { 839 blk_queue_flag_clear(QUEUE_FLAG_HW_WC, q); 840 blk_queue_flag_clear(QUEUE_FLAG_WC, q); 841 } 842 if (fua) 843 blk_queue_flag_set(QUEUE_FLAG_FUA, q); 844 else 845 blk_queue_flag_clear(QUEUE_FLAG_FUA, q); 846 } 847 EXPORT_SYMBOL_GPL(blk_queue_write_cache); 848 849 /** 850 * blk_queue_required_elevator_features - Set a queue required elevator features 851 * @q: the request queue for the target device 852 * @features: Required elevator features OR'ed together 853 * 854 * Tell the block layer that for the device controlled through @q, only the 855 * only elevators that can be used are those that implement at least the set of 856 * features specified by @features. 857 */ 858 void blk_queue_required_elevator_features(struct request_queue *q, 859 unsigned int features) 860 { 861 q->required_elevator_features = features; 862 } 863 EXPORT_SYMBOL_GPL(blk_queue_required_elevator_features); 864 865 /** 866 * blk_queue_can_use_dma_map_merging - configure queue for merging segments. 867 * @q: the request queue for the device 868 * @dev: the device pointer for dma 869 * 870 * Tell the block layer about merging the segments by dma map of @q. 871 */ 872 bool blk_queue_can_use_dma_map_merging(struct request_queue *q, 873 struct device *dev) 874 { 875 unsigned long boundary = dma_get_merge_boundary(dev); 876 877 if (!boundary) 878 return false; 879 880 /* No need to update max_segment_size. see blk_queue_virt_boundary() */ 881 blk_queue_virt_boundary(q, boundary); 882 883 return true; 884 } 885 EXPORT_SYMBOL_GPL(blk_queue_can_use_dma_map_merging); 886 887 /** 888 * disk_set_zoned - inidicate a zoned device 889 * @disk: gendisk to configure 890 */ 891 void disk_set_zoned(struct gendisk *disk) 892 { 893 struct request_queue *q = disk->queue; 894 895 WARN_ON_ONCE(!IS_ENABLED(CONFIG_BLK_DEV_ZONED)); 896 897 /* 898 * Set the zone write granularity to the device logical block 899 * size by default. The driver can change this value if needed. 900 */ 901 q->limits.zoned = true; 902 blk_queue_zone_write_granularity(q, queue_logical_block_size(q)); 903 } 904 EXPORT_SYMBOL_GPL(disk_set_zoned); 905 906 int bdev_alignment_offset(struct block_device *bdev) 907 { 908 struct request_queue *q = bdev_get_queue(bdev); 909 910 if (q->limits.misaligned) 911 return -1; 912 if (bdev_is_partition(bdev)) 913 return queue_limit_alignment_offset(&q->limits, 914 bdev->bd_start_sect); 915 return q->limits.alignment_offset; 916 } 917 EXPORT_SYMBOL_GPL(bdev_alignment_offset); 918 919 unsigned int bdev_discard_alignment(struct block_device *bdev) 920 { 921 struct request_queue *q = bdev_get_queue(bdev); 922 923 if (bdev_is_partition(bdev)) 924 return queue_limit_discard_alignment(&q->limits, 925 bdev->bd_start_sect); 926 return q->limits.discard_alignment; 927 } 928 EXPORT_SYMBOL_GPL(bdev_discard_alignment); 929