| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Functions related to setting various queue properties from drivers |
| */ |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/init.h> |
| #include <linux/bio.h> |
| #include <linux/blkdev.h> |
| #include <linux/pagemap.h> |
| #include <linux/backing-dev-defs.h> |
| #include <linux/gcd.h> |
| #include <linux/lcm.h> |
| #include <linux/jiffies.h> |
| #include <linux/gfp.h> |
| #include <linux/dma-mapping.h> |
| |
| #include "blk.h" |
| #include "blk-rq-qos.h" |
| #include "blk-wbt.h" |
| |
| void blk_queue_rq_timeout(struct request_queue *q, unsigned int timeout) |
| { |
| q->rq_timeout = timeout; |
| } |
| EXPORT_SYMBOL_GPL(blk_queue_rq_timeout); |
| |
| /** |
| * blk_set_stacking_limits - set default limits for stacking devices |
| * @lim: the queue_limits structure to reset |
| * |
| * Prepare queue limits for applying limits from underlying devices using |
| * blk_stack_limits(). |
| */ |
| void blk_set_stacking_limits(struct queue_limits *lim) |
| { |
| memset(lim, 0, sizeof(*lim)); |
| lim->logical_block_size = SECTOR_SIZE; |
| lim->physical_block_size = SECTOR_SIZE; |
| lim->io_min = SECTOR_SIZE; |
| lim->discard_granularity = SECTOR_SIZE; |
| lim->dma_alignment = SECTOR_SIZE - 1; |
| lim->seg_boundary_mask = BLK_SEG_BOUNDARY_MASK; |
| |
| /* Inherit limits from component devices */ |
| lim->max_segments = USHRT_MAX; |
| lim->max_discard_segments = USHRT_MAX; |
| lim->max_hw_sectors = UINT_MAX; |
| lim->max_segment_size = UINT_MAX; |
| lim->max_sectors = UINT_MAX; |
| lim->max_dev_sectors = UINT_MAX; |
| lim->max_write_zeroes_sectors = UINT_MAX; |
| lim->max_zone_append_sectors = UINT_MAX; |
| lim->max_user_discard_sectors = UINT_MAX; |
| } |
| EXPORT_SYMBOL(blk_set_stacking_limits); |
| |
| static void blk_apply_bdi_limits(struct backing_dev_info *bdi, |
| struct queue_limits *lim) |
| { |
| /* |
| * For read-ahead of large files to be effective, we need to read ahead |
| * at least twice the optimal I/O size. |
| */ |
| bdi->ra_pages = max(lim->io_opt * 2 / PAGE_SIZE, VM_READAHEAD_PAGES); |
| bdi->io_pages = lim->max_sectors >> PAGE_SECTORS_SHIFT; |
| } |
| |
| static int blk_validate_zoned_limits(struct queue_limits *lim) |
| { |
| if (!lim->zoned) { |
| if (WARN_ON_ONCE(lim->max_open_zones) || |
| WARN_ON_ONCE(lim->max_active_zones) || |
| WARN_ON_ONCE(lim->zone_write_granularity) || |
| WARN_ON_ONCE(lim->max_zone_append_sectors)) |
| return -EINVAL; |
| return 0; |
| } |
| |
| if (WARN_ON_ONCE(!IS_ENABLED(CONFIG_BLK_DEV_ZONED))) |
| return -EINVAL; |
| |
| if (lim->zone_write_granularity < lim->logical_block_size) |
| lim->zone_write_granularity = lim->logical_block_size; |
| |
| if (lim->max_zone_append_sectors) { |
| /* |
| * The Zone Append size is limited by the maximum I/O size |
| * and the zone size given that it can't span zones. |
| */ |
| lim->max_zone_append_sectors = |
| min3(lim->max_hw_sectors, |
| lim->max_zone_append_sectors, |
| lim->chunk_sectors); |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * Check that the limits in lim are valid, initialize defaults for unset |
| * values, and cap values based on others where needed. |
| */ |
| static int blk_validate_limits(struct queue_limits *lim) |
| { |
| unsigned int max_hw_sectors; |
| unsigned int logical_block_sectors; |
| |
| /* |
| * Unless otherwise specified, default to 512 byte logical blocks and a |
| * physical block size equal to the logical block size. |
| */ |
| if (!lim->logical_block_size) |
| lim->logical_block_size = SECTOR_SIZE; |
| if (lim->physical_block_size < lim->logical_block_size) |
| lim->physical_block_size = lim->logical_block_size; |
| |
| /* |
| * The minimum I/O size defaults to the physical block size unless |
| * explicitly overridden. |
| */ |
| if (lim->io_min < lim->physical_block_size) |
| lim->io_min = lim->physical_block_size; |
| |
| /* |
| * max_hw_sectors has a somewhat weird default for historical reason, |
| * but driver really should set their own instead of relying on this |
| * value. |
| * |
| * The block layer relies on the fact that every driver can |
| * handle at lest a page worth of data per I/O, and needs the value |
| * aligned to the logical block size. |
| */ |
| if (!lim->max_hw_sectors) |
| lim->max_hw_sectors = BLK_SAFE_MAX_SECTORS; |
| if (WARN_ON_ONCE(lim->max_hw_sectors < PAGE_SECTORS)) |
| return -EINVAL; |
| logical_block_sectors = lim->logical_block_size >> SECTOR_SHIFT; |
| if (WARN_ON_ONCE(logical_block_sectors > lim->max_hw_sectors)) |
| return -EINVAL; |
| lim->max_hw_sectors = round_down(lim->max_hw_sectors, |
| logical_block_sectors); |
| |
| /* |
| * The actual max_sectors value is a complex beast and also takes the |
| * max_dev_sectors value (set by SCSI ULPs) and a user configurable |
| * value into account. The ->max_sectors value is always calculated |
| * from these, so directly setting it won't have any effect. |
| */ |
| max_hw_sectors = min_not_zero(lim->max_hw_sectors, |
| lim->max_dev_sectors); |
| if (lim->max_user_sectors) { |
| if (lim->max_user_sectors < PAGE_SIZE / SECTOR_SIZE) |
| return -EINVAL; |
| lim->max_sectors = min(max_hw_sectors, lim->max_user_sectors); |
| } else { |
| lim->max_sectors = min(max_hw_sectors, BLK_DEF_MAX_SECTORS_CAP); |
| } |
| lim->max_sectors = round_down(lim->max_sectors, |
| logical_block_sectors); |
| |
| /* |
| * Random default for the maximum number of segments. Driver should not |
| * rely on this and set their own. |
| */ |
| if (!lim->max_segments) |
| lim->max_segments = BLK_MAX_SEGMENTS; |
| |
| lim->max_discard_sectors = |
| min(lim->max_hw_discard_sectors, lim->max_user_discard_sectors); |
| |
| if (!lim->max_discard_segments) |
| lim->max_discard_segments = 1; |
| |
| if (lim->discard_granularity < lim->physical_block_size) |
| lim->discard_granularity = lim->physical_block_size; |
| |
| /* |
| * By default there is no limit on the segment boundary alignment, |
| * but if there is one it can't be smaller than the page size as |
| * that would break all the normal I/O patterns. |
| */ |
| if (!lim->seg_boundary_mask) |
| lim->seg_boundary_mask = BLK_SEG_BOUNDARY_MASK; |
| if (WARN_ON_ONCE(lim->seg_boundary_mask < PAGE_SIZE - 1)) |
| return -EINVAL; |
| |
| /* |
| * Stacking device may have both virtual boundary and max segment |
| * size limit, so allow this setting now, and long-term the two |
| * might need to move out of stacking limits since we have immutable |
| * bvec and lower layer bio splitting is supposed to handle the two |
| * correctly. |
| */ |
| if (lim->virt_boundary_mask) { |
| if (!lim->max_segment_size) |
| lim->max_segment_size = UINT_MAX; |
| } else { |
| /* |
| * The maximum segment size has an odd historic 64k default that |
| * drivers probably should override. Just like the I/O size we |
| * require drivers to at least handle a full page per segment. |
| */ |
| if (!lim->max_segment_size) |
| lim->max_segment_size = BLK_MAX_SEGMENT_SIZE; |
| if (WARN_ON_ONCE(lim->max_segment_size < PAGE_SIZE)) |
| return -EINVAL; |
| } |
| |
| /* |
| * We require drivers to at least do logical block aligned I/O, but |
| * historically could not check for that due to the separate calls |
| * to set the limits. Once the transition is finished the check |
| * below should be narrowed down to check the logical block size. |
| */ |
| if (!lim->dma_alignment) |
| lim->dma_alignment = SECTOR_SIZE - 1; |
| if (WARN_ON_ONCE(lim->dma_alignment > PAGE_SIZE)) |
| return -EINVAL; |
| |
| if (lim->alignment_offset) { |
| lim->alignment_offset &= (lim->physical_block_size - 1); |
| lim->misaligned = 0; |
| } |
| |
| return blk_validate_zoned_limits(lim); |
| } |
| |
| /* |
| * Set the default limits for a newly allocated queue. @lim contains the |
| * initial limits set by the driver, which could be no limit in which case |
| * all fields are cleared to zero. |
| */ |
| int blk_set_default_limits(struct queue_limits *lim) |
| { |
| /* |
| * Most defaults are set by capping the bounds in blk_validate_limits, |
| * but max_user_discard_sectors is special and needs an explicit |
| * initialization to the max value here. |
| */ |
| lim->max_user_discard_sectors = UINT_MAX; |
| return blk_validate_limits(lim); |
| } |
| |
| /** |
| * queue_limits_commit_update - commit an atomic update of queue limits |
| * @q: queue to update |
| * @lim: limits to apply |
| * |
| * Apply the limits in @lim that were obtained from queue_limits_start_update() |
| * and updated by the caller to @q. |
| * |
| * Returns 0 if successful, else a negative error code. |
| */ |
| int queue_limits_commit_update(struct request_queue *q, |
| struct queue_limits *lim) |
| __releases(q->limits_lock) |
| { |
| int error = blk_validate_limits(lim); |
| |
| if (!error) { |
| q->limits = *lim; |
| if (q->disk) |
| blk_apply_bdi_limits(q->disk->bdi, lim); |
| } |
| mutex_unlock(&q->limits_lock); |
| return error; |
| } |
| EXPORT_SYMBOL_GPL(queue_limits_commit_update); |
| |
| /** |
| * queue_limits_set - apply queue limits to queue |
| * @q: queue to update |
| * @lim: limits to apply |
| * |
| * Apply the limits in @lim that were freshly initialized to @q. |
| * To update existing limits use queue_limits_start_update() and |
| * queue_limits_commit_update() instead. |
| * |
| * Returns 0 if successful, else a negative error code. |
| */ |
| int queue_limits_set(struct request_queue *q, struct queue_limits *lim) |
| { |
| mutex_lock(&q->limits_lock); |
| return queue_limits_commit_update(q, lim); |
| } |
| EXPORT_SYMBOL_GPL(queue_limits_set); |
| |
| /** |
| * blk_queue_chunk_sectors - set size of the chunk for this queue |
| * @q: the request queue for the device |
| * @chunk_sectors: chunk sectors in the usual 512b unit |
| * |
| * Description: |
| * If a driver doesn't want IOs to cross a given chunk size, it can set |
| * this limit and prevent merging across chunks. Note that the block layer |
| * must accept a page worth of data at any offset. So if the crossing of |
| * chunks is a hard limitation in the driver, it must still be prepared |
| * to split single page bios. |
| **/ |
| void blk_queue_chunk_sectors(struct request_queue *q, unsigned int chunk_sectors) |
| { |
| q->limits.chunk_sectors = chunk_sectors; |
| } |
| EXPORT_SYMBOL(blk_queue_chunk_sectors); |
| |
| /** |
| * blk_queue_max_discard_sectors - set max sectors for a single discard |
| * @q: the request queue for the device |
| * @max_discard_sectors: maximum number of sectors to discard |
| **/ |
| void blk_queue_max_discard_sectors(struct request_queue *q, |
| unsigned int max_discard_sectors) |
| { |
| struct queue_limits *lim = &q->limits; |
| |
| lim->max_hw_discard_sectors = max_discard_sectors; |
| lim->max_discard_sectors = |
| min(max_discard_sectors, lim->max_user_discard_sectors); |
| } |
| EXPORT_SYMBOL(blk_queue_max_discard_sectors); |
| |
| /** |
| * blk_queue_max_secure_erase_sectors - set max sectors for a secure erase |
| * @q: the request queue for the device |
| * @max_sectors: maximum number of sectors to secure_erase |
| **/ |
| void blk_queue_max_secure_erase_sectors(struct request_queue *q, |
| unsigned int max_sectors) |
| { |
| q->limits.max_secure_erase_sectors = max_sectors; |
| } |
| EXPORT_SYMBOL(blk_queue_max_secure_erase_sectors); |
| |
| /** |
| * blk_queue_max_write_zeroes_sectors - set max sectors for a single |
| * write zeroes |
| * @q: the request queue for the device |
| * @max_write_zeroes_sectors: maximum number of sectors to write per command |
| **/ |
| void blk_queue_max_write_zeroes_sectors(struct request_queue *q, |
| unsigned int max_write_zeroes_sectors) |
| { |
| q->limits.max_write_zeroes_sectors = max_write_zeroes_sectors; |
| } |
| EXPORT_SYMBOL(blk_queue_max_write_zeroes_sectors); |
| |
| /** |
| * blk_queue_max_zone_append_sectors - set max sectors for a single zone append |
| * @q: the request queue for the device |
| * @max_zone_append_sectors: maximum number of sectors to write per command |
| * |
| * Sets the maximum number of sectors allowed for zone append commands. If |
| * Specifying 0 for @max_zone_append_sectors indicates that the queue does |
| * not natively support zone append operations and that the block layer must |
| * emulate these operations using regular writes. |
| **/ |
| void blk_queue_max_zone_append_sectors(struct request_queue *q, |
| unsigned int max_zone_append_sectors) |
| { |
| unsigned int max_sectors = 0; |
| |
| if (WARN_ON(!blk_queue_is_zoned(q))) |
| return; |
| |
| if (max_zone_append_sectors) { |
| max_sectors = min(q->limits.max_hw_sectors, |
| max_zone_append_sectors); |
| max_sectors = min(q->limits.chunk_sectors, max_sectors); |
| |
| /* |
| * Signal eventual driver bugs resulting in the max_zone_append |
| * sectors limit being 0 due to the chunk_sectors limit (zone |
| * size) not set or the max_hw_sectors limit not set. |
| */ |
| WARN_ON_ONCE(!max_sectors); |
| } |
| |
| q->limits.max_zone_append_sectors = max_sectors; |
| } |
| EXPORT_SYMBOL_GPL(blk_queue_max_zone_append_sectors); |
| |
| /** |
| * blk_queue_logical_block_size - set logical block size for the queue |
| * @q: the request queue for the device |
| * @size: the logical block size, in bytes |
| * |
| * Description: |
| * This should be set to the lowest possible block size that the |
| * storage device can address. The default of 512 covers most |
| * hardware. |
| **/ |
| void blk_queue_logical_block_size(struct request_queue *q, unsigned int size) |
| { |
| struct queue_limits *limits = &q->limits; |
| |
| limits->logical_block_size = size; |
| |
| if (limits->discard_granularity < limits->logical_block_size) |
| limits->discard_granularity = limits->logical_block_size; |
| |
| if (limits->physical_block_size < size) |
| limits->physical_block_size = size; |
| |
| if (limits->io_min < limits->physical_block_size) |
| limits->io_min = limits->physical_block_size; |
| |
| limits->max_hw_sectors = |
| round_down(limits->max_hw_sectors, size >> SECTOR_SHIFT); |
| limits->max_sectors = |
| round_down(limits->max_sectors, size >> SECTOR_SHIFT); |
| } |
| EXPORT_SYMBOL(blk_queue_logical_block_size); |
| |
| /** |
| * blk_queue_physical_block_size - set physical block size for the queue |
| * @q: the request queue for the device |
| * @size: the physical block size, in bytes |
| * |
| * Description: |
| * This should be set to the lowest possible sector size that the |
| * hardware can operate on without reverting to read-modify-write |
| * operations. |
| */ |
| void blk_queue_physical_block_size(struct request_queue *q, unsigned int size) |
| { |
| q->limits.physical_block_size = size; |
| |
| if (q->limits.physical_block_size < q->limits.logical_block_size) |
| q->limits.physical_block_size = q->limits.logical_block_size; |
| |
| if (q->limits.discard_granularity < q->limits.physical_block_size) |
| q->limits.discard_granularity = q->limits.physical_block_size; |
| |
| if (q->limits.io_min < q->limits.physical_block_size) |
| q->limits.io_min = q->limits.physical_block_size; |
| } |
| EXPORT_SYMBOL(blk_queue_physical_block_size); |
| |
| /** |
| * blk_queue_zone_write_granularity - set zone write granularity for the queue |
| * @q: the request queue for the zoned device |
| * @size: the zone write granularity size, in bytes |
| * |
| * Description: |
| * This should be set to the lowest possible size allowing to write in |
| * sequential zones of a zoned block device. |
| */ |
| void blk_queue_zone_write_granularity(struct request_queue *q, |
| unsigned int size) |
| { |
| if (WARN_ON_ONCE(!blk_queue_is_zoned(q))) |
| return; |
| |
| q->limits.zone_write_granularity = size; |
| |
| if (q->limits.zone_write_granularity < q->limits.logical_block_size) |
| q->limits.zone_write_granularity = q->limits.logical_block_size; |
| } |
| EXPORT_SYMBOL_GPL(blk_queue_zone_write_granularity); |
| |
| /** |
| * blk_queue_alignment_offset - set physical block alignment offset |
| * @q: the request queue for the device |
| * @offset: alignment offset in bytes |
| * |
| * Description: |
| * Some devices are naturally misaligned to compensate for things like |
| * the legacy DOS partition table 63-sector offset. Low-level drivers |
| * should call this function for devices whose first sector is not |
| * naturally aligned. |
| */ |
| void blk_queue_alignment_offset(struct request_queue *q, unsigned int offset) |
| { |
| q->limits.alignment_offset = |
| offset & (q->limits.physical_block_size - 1); |
| q->limits.misaligned = 0; |
| } |
| EXPORT_SYMBOL(blk_queue_alignment_offset); |
| |
| void disk_update_readahead(struct gendisk *disk) |
| { |
| blk_apply_bdi_limits(disk->bdi, &disk->queue->limits); |
| } |
| EXPORT_SYMBOL_GPL(disk_update_readahead); |
| |
| /** |
| * blk_limits_io_min - set minimum request size for a device |
| * @limits: the queue limits |
| * @min: smallest I/O size in bytes |
| * |
| * Description: |
| * Some devices have an internal block size bigger than the reported |
| * hardware sector size. This function can be used to signal the |
| * smallest I/O the device can perform without incurring a performance |
| * penalty. |
| */ |
| void blk_limits_io_min(struct queue_limits *limits, unsigned int min) |
| { |
| limits->io_min = min; |
| |
| if (limits->io_min < limits->logical_block_size) |
| limits->io_min = limits->logical_block_size; |
| |
| if (limits->io_min < limits->physical_block_size) |
| limits->io_min = limits->physical_block_size; |
| } |
| EXPORT_SYMBOL(blk_limits_io_min); |
| |
| /** |
| * blk_queue_io_min - set minimum request size for the queue |
| * @q: the request queue for the device |
| * @min: smallest I/O size in bytes |
| * |
| * Description: |
| * Storage devices may report a granularity or preferred minimum I/O |
| * size which is the smallest request the device can perform without |
| * incurring a performance penalty. For disk drives this is often the |
| * physical block size. For RAID arrays it is often the stripe chunk |
| * size. A properly aligned multiple of minimum_io_size is the |
| * preferred request size for workloads where a high number of I/O |
| * operations is desired. |
| */ |
| void blk_queue_io_min(struct request_queue *q, unsigned int min) |
| { |
| blk_limits_io_min(&q->limits, min); |
| } |
| EXPORT_SYMBOL(blk_queue_io_min); |
| |
| /** |
| * blk_limits_io_opt - set optimal request size for a device |
| * @limits: the queue limits |
| * @opt: smallest I/O size in bytes |
| * |
| * Description: |
| * Storage devices may report an optimal I/O size, which is the |
| * device's preferred unit for sustained I/O. This is rarely reported |
| * for disk drives. For RAID arrays it is usually the stripe width or |
| * the internal track size. A properly aligned multiple of |
| * optimal_io_size is the preferred request size for workloads where |
| * sustained throughput is desired. |
| */ |
| void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt) |
| { |
| limits->io_opt = opt; |
| } |
| EXPORT_SYMBOL(blk_limits_io_opt); |
| |
| static int queue_limit_alignment_offset(const struct queue_limits *lim, |
| sector_t sector) |
| { |
| unsigned int granularity = max(lim->physical_block_size, lim->io_min); |
| unsigned int alignment = sector_div(sector, granularity >> SECTOR_SHIFT) |
| << SECTOR_SHIFT; |
| |
| return (granularity + lim->alignment_offset - alignment) % granularity; |
| } |
| |
| static unsigned int queue_limit_discard_alignment( |
| const struct queue_limits *lim, sector_t sector) |
| { |
| unsigned int alignment, granularity, offset; |
| |
| if (!lim->max_discard_sectors) |
| return 0; |
| |
| /* Why are these in bytes, not sectors? */ |
| alignment = lim->discard_alignment >> SECTOR_SHIFT; |
| granularity = lim->discard_granularity >> SECTOR_SHIFT; |
| if (!granularity) |
| return 0; |
| |
| /* Offset of the partition start in 'granularity' sectors */ |
| offset = sector_div(sector, granularity); |
| |
| /* And why do we do this modulus *again* in blkdev_issue_discard()? */ |
| offset = (granularity + alignment - offset) % granularity; |
| |
| /* Turn it back into bytes, gaah */ |
| return offset << SECTOR_SHIFT; |
| } |
| |
| static unsigned int blk_round_down_sectors(unsigned int sectors, unsigned int lbs) |
| { |
| sectors = round_down(sectors, lbs >> SECTOR_SHIFT); |
| if (sectors < PAGE_SIZE >> SECTOR_SHIFT) |
| sectors = PAGE_SIZE >> SECTOR_SHIFT; |
| return sectors; |
| } |
| |
| /** |
| * blk_stack_limits - adjust queue_limits for stacked devices |
| * @t: the stacking driver limits (top device) |
| * @b: the underlying queue limits (bottom, component device) |
| * @start: first data sector within component device |
| * |
| * Description: |
| * This function is used by stacking drivers like MD and DM to ensure |
| * that all component devices have compatible block sizes and |
| * alignments. The stacking driver must provide a queue_limits |
| * struct (top) and then iteratively call the stacking function for |
| * all component (bottom) devices. The stacking function will |
| * attempt to combine the values and ensure proper alignment. |
| * |
| * Returns 0 if the top and bottom queue_limits are compatible. The |
| * top device's block sizes and alignment offsets may be adjusted to |
| * ensure alignment with the bottom device. If no compatible sizes |
| * and alignments exist, -1 is returned and the resulting top |
| * queue_limits will have the misaligned flag set to indicate that |
| * the alignment_offset is undefined. |
| */ |
| int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, |
| sector_t start) |
| { |
| unsigned int top, bottom, alignment, ret = 0; |
| |
| t->max_sectors = min_not_zero(t->max_sectors, b->max_sectors); |
| t->max_user_sectors = min_not_zero(t->max_user_sectors, |
| b->max_user_sectors); |
| t->max_hw_sectors = min_not_zero(t->max_hw_sectors, b->max_hw_sectors); |
| t->max_dev_sectors = min_not_zero(t->max_dev_sectors, b->max_dev_sectors); |
| t->max_write_zeroes_sectors = min(t->max_write_zeroes_sectors, |
| b->max_write_zeroes_sectors); |
| t->max_zone_append_sectors = min(queue_limits_max_zone_append_sectors(t), |
| queue_limits_max_zone_append_sectors(b)); |
| t->bounce = max(t->bounce, b->bounce); |
| |
| t->seg_boundary_mask = min_not_zero(t->seg_boundary_mask, |
| b->seg_boundary_mask); |
| t->virt_boundary_mask = min_not_zero(t->virt_boundary_mask, |
| b->virt_boundary_mask); |
| |
| t->max_segments = min_not_zero(t->max_segments, b->max_segments); |
| t->max_discard_segments = min_not_zero(t->max_discard_segments, |
| b->max_discard_segments); |
| t->max_integrity_segments = min_not_zero(t->max_integrity_segments, |
| b->max_integrity_segments); |
| |
| t->max_segment_size = min_not_zero(t->max_segment_size, |
| b->max_segment_size); |
| |
| t->misaligned |= b->misaligned; |
| |
| alignment = queue_limit_alignment_offset(b, start); |
| |
| /* Bottom device has different alignment. Check that it is |
| * compatible with the current top alignment. |
| */ |
| if (t->alignment_offset != alignment) { |
| |
| top = max(t->physical_block_size, t->io_min) |
| + t->alignment_offset; |
| bottom = max(b->physical_block_size, b->io_min) + alignment; |
| |
| /* Verify that top and bottom intervals line up */ |
| if (max(top, bottom) % min(top, bottom)) { |
| t->misaligned = 1; |
| ret = -1; |
| } |
| } |
| |
| t->logical_block_size = max(t->logical_block_size, |
| b->logical_block_size); |
| |
| t->physical_block_size = max(t->physical_block_size, |
| b->physical_block_size); |
| |
| t->io_min = max(t->io_min, b->io_min); |
| t->io_opt = lcm_not_zero(t->io_opt, b->io_opt); |
| t->dma_alignment = max(t->dma_alignment, b->dma_alignment); |
| |
| /* Set non-power-of-2 compatible chunk_sectors boundary */ |
| if (b->chunk_sectors) |
| t->chunk_sectors = gcd(t->chunk_sectors, b->chunk_sectors); |
| |
| /* Physical block size a multiple of the logical block size? */ |
| if (t->physical_block_size & (t->logical_block_size - 1)) { |
| t->physical_block_size = t->logical_block_size; |
| t->misaligned = 1; |
| ret = -1; |
| } |
| |
| /* Minimum I/O a multiple of the physical block size? */ |
| if (t->io_min & (t->physical_block_size - 1)) { |
| t->io_min = t->physical_block_size; |
| t->misaligned = 1; |
| ret = -1; |
| } |
| |
| /* Optimal I/O a multiple of the physical block size? */ |
| if (t->io_opt & (t->physical_block_size - 1)) { |
| t->io_opt = 0; |
| t->misaligned = 1; |
| ret = -1; |
| } |
| |
| /* chunk_sectors a multiple of the physical block size? */ |
| if ((t->chunk_sectors << 9) & (t->physical_block_size - 1)) { |
| t->chunk_sectors = 0; |
| t->misaligned = 1; |
| ret = -1; |
| } |
| |
| t->raid_partial_stripes_expensive = |
| max(t->raid_partial_stripes_expensive, |
| b->raid_partial_stripes_expensive); |
| |
| /* Find lowest common alignment_offset */ |
| t->alignment_offset = lcm_not_zero(t->alignment_offset, alignment) |
| % max(t->physical_block_size, t->io_min); |
| |
| /* Verify that new alignment_offset is on a logical block boundary */ |
| if (t->alignment_offset & (t->logical_block_size - 1)) { |
| t->misaligned = 1; |
| ret = -1; |
| } |
| |
| t->max_sectors = blk_round_down_sectors(t->max_sectors, t->logical_block_size); |
| t->max_hw_sectors = blk_round_down_sectors(t->max_hw_sectors, t->logical_block_size); |
| t->max_dev_sectors = blk_round_down_sectors(t->max_dev_sectors, t->logical_block_size); |
| |
| /* Discard alignment and granularity */ |
| if (b->discard_granularity) { |
| alignment = queue_limit_discard_alignment(b, start); |
| |
| if (t->discard_granularity != 0 && |
| t->discard_alignment != alignment) { |
| top = t->discard_granularity + t->discard_alignment; |
| bottom = b->discard_granularity + alignment; |
| |
| /* Verify that top and bottom intervals line up */ |
| if ((max(top, bottom) % min(top, bottom)) != 0) |
| t->discard_misaligned = 1; |
| } |
| |
| t->max_discard_sectors = min_not_zero(t->max_discard_sectors, |
| b->max_discard_sectors); |
| t->max_hw_discard_sectors = min_not_zero(t->max_hw_discard_sectors, |
| b->max_hw_discard_sectors); |
| t->discard_granularity = max(t->discard_granularity, |
| b->discard_granularity); |
| t->discard_alignment = lcm_not_zero(t->discard_alignment, alignment) % |
| t->discard_granularity; |
| } |
| t->max_secure_erase_sectors = min_not_zero(t->max_secure_erase_sectors, |
| b->max_secure_erase_sectors); |
| t->zone_write_granularity = max(t->zone_write_granularity, |
| b->zone_write_granularity); |
| t->zoned = max(t->zoned, b->zoned); |
| if (!t->zoned) { |
| t->zone_write_granularity = 0; |
| t->max_zone_append_sectors = 0; |
| } |
| return ret; |
| } |
| EXPORT_SYMBOL(blk_stack_limits); |
| |
| /** |
| * queue_limits_stack_bdev - adjust queue_limits for stacked devices |
| * @t: the stacking driver limits (top device) |
| * @bdev: the underlying block device (bottom) |
| * @offset: offset to beginning of data within component device |
| * @pfx: prefix to use for warnings logged |
| * |
| * Description: |
| * This function is used by stacking drivers like MD and DM to ensure |
| * that all component devices have compatible block sizes and |
| * alignments. The stacking driver must provide a queue_limits |
| * struct (top) and then iteratively call the stacking function for |
| * all component (bottom) devices. The stacking function will |
| * attempt to combine the values and ensure proper alignment. |
| */ |
| void queue_limits_stack_bdev(struct queue_limits *t, struct block_device *bdev, |
| sector_t offset, const char *pfx) |
| { |
| if (blk_stack_limits(t, &bdev_get_queue(bdev)->limits, |
| get_start_sect(bdev) + offset)) |
| pr_notice("%s: Warning: Device %pg is misaligned\n", |
| pfx, bdev); |
| } |
| EXPORT_SYMBOL_GPL(queue_limits_stack_bdev); |
| |
| /** |
| * blk_queue_update_dma_pad - update pad mask |
| * @q: the request queue for the device |
| * @mask: pad mask |
| * |
| * Update dma pad mask. |
| * |
| * Appending pad buffer to a request modifies the last entry of a |
| * scatter list such that it includes the pad buffer. |
| **/ |
| void blk_queue_update_dma_pad(struct request_queue *q, unsigned int mask) |
| { |
| if (mask > q->dma_pad_mask) |
| q->dma_pad_mask = mask; |
| } |
| EXPORT_SYMBOL(blk_queue_update_dma_pad); |
| |
| /** |
| * blk_set_queue_depth - tell the block layer about the device queue depth |
| * @q: the request queue for the device |
| * @depth: queue depth |
| * |
| */ |
| void blk_set_queue_depth(struct request_queue *q, unsigned int depth) |
| { |
| q->queue_depth = depth; |
| rq_qos_queue_depth_changed(q); |
| } |
| EXPORT_SYMBOL(blk_set_queue_depth); |
| |
| /** |
| * blk_queue_write_cache - configure queue's write cache |
| * @q: the request queue for the device |
| * @wc: write back cache on or off |
| * @fua: device supports FUA writes, if true |
| * |
| * Tell the block layer about the write cache of @q. |
| */ |
| void blk_queue_write_cache(struct request_queue *q, bool wc, bool fua) |
| { |
| if (wc) { |
| blk_queue_flag_set(QUEUE_FLAG_HW_WC, q); |
| blk_queue_flag_set(QUEUE_FLAG_WC, q); |
| } else { |
| blk_queue_flag_clear(QUEUE_FLAG_HW_WC, q); |
| blk_queue_flag_clear(QUEUE_FLAG_WC, q); |
| } |
| if (fua) |
| blk_queue_flag_set(QUEUE_FLAG_FUA, q); |
| else |
| blk_queue_flag_clear(QUEUE_FLAG_FUA, q); |
| } |
| EXPORT_SYMBOL_GPL(blk_queue_write_cache); |
| |
| /** |
| * disk_set_zoned - inidicate a zoned device |
| * @disk: gendisk to configure |
| */ |
| void disk_set_zoned(struct gendisk *disk) |
| { |
| struct request_queue *q = disk->queue; |
| |
| WARN_ON_ONCE(!IS_ENABLED(CONFIG_BLK_DEV_ZONED)); |
| |
| /* |
| * Set the zone write granularity to the device logical block |
| * size by default. The driver can change this value if needed. |
| */ |
| q->limits.zoned = true; |
| blk_queue_zone_write_granularity(q, queue_logical_block_size(q)); |
| } |
| EXPORT_SYMBOL_GPL(disk_set_zoned); |
| |
| int bdev_alignment_offset(struct block_device *bdev) |
| { |
| struct request_queue *q = bdev_get_queue(bdev); |
| |
| if (q->limits.misaligned) |
| return -1; |
| if (bdev_is_partition(bdev)) |
| return queue_limit_alignment_offset(&q->limits, |
| bdev->bd_start_sect); |
| return q->limits.alignment_offset; |
| } |
| EXPORT_SYMBOL_GPL(bdev_alignment_offset); |
| |
| unsigned int bdev_discard_alignment(struct block_device *bdev) |
| { |
| struct request_queue *q = bdev_get_queue(bdev); |
| |
| if (bdev_is_partition(bdev)) |
| return queue_limit_discard_alignment(&q->limits, |
| bdev->bd_start_sect); |
| return q->limits.discard_alignment; |
| } |
| EXPORT_SYMBOL_GPL(bdev_discard_alignment); |