linux/block/blk-settings.c
John Garry fe3d508ba9 block: Validate logical block size in blk_validate_limits()
Some drivers validate that their own logical block size. It is no harm to
always do this, so validate in blk_validate_limits().

This allows us to remove the validation in most of those drivers.

Add a comment to blk_validate_block_size() to inform users that self-
validation of LBS is usually unnecessary.

Signed-off-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240708091651.177447-3-john.g.garry@oracle.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-07-09 00:00:17 -06:00

810 lines
25 KiB
C

// 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/blk-integrity.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);
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->features & BLK_FEAT_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;
/*
* Given that active zones include open zones, the maximum number of
* open zones cannot be larger than the maximum number of active zones.
*/
if (lim->max_active_zones &&
lim->max_open_zones > lim->max_active_zones)
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;
}
static int blk_validate_integrity_limits(struct queue_limits *lim)
{
struct blk_integrity *bi = &lim->integrity;
if (!bi->tuple_size) {
if (bi->csum_type != BLK_INTEGRITY_CSUM_NONE ||
bi->tag_size || ((bi->flags & BLK_INTEGRITY_REF_TAG))) {
pr_warn("invalid PI settings.\n");
return -EINVAL;
}
return 0;
}
if (!IS_ENABLED(CONFIG_BLK_DEV_INTEGRITY)) {
pr_warn("integrity support disabled.\n");
return -EINVAL;
}
if (bi->csum_type == BLK_INTEGRITY_CSUM_NONE &&
(bi->flags & BLK_INTEGRITY_REF_TAG)) {
pr_warn("ref tag not support without checksum.\n");
return -EINVAL;
}
if (!bi->interval_exp)
bi->interval_exp = ilog2(lim->logical_block_size);
return 0;
}
/*
* Returns max guaranteed bytes which we can fit in a bio.
*
* We request that an atomic_write is ITER_UBUF iov_iter (so a single vector),
* so we assume that we can fit in at least PAGE_SIZE in a segment, apart from
* the first and last segments.
*/
static unsigned int blk_queue_max_guaranteed_bio(struct queue_limits *lim)
{
unsigned int max_segments = min(BIO_MAX_VECS, lim->max_segments);
unsigned int length;
length = min(max_segments, 2) * lim->logical_block_size;
if (max_segments > 2)
length += (max_segments - 2) * PAGE_SIZE;
return length;
}
static void blk_atomic_writes_update_limits(struct queue_limits *lim)
{
unsigned int unit_limit = min(lim->max_hw_sectors << SECTOR_SHIFT,
blk_queue_max_guaranteed_bio(lim));
unit_limit = rounddown_pow_of_two(unit_limit);
lim->atomic_write_max_sectors =
min(lim->atomic_write_hw_max >> SECTOR_SHIFT,
lim->max_hw_sectors);
lim->atomic_write_unit_min =
min(lim->atomic_write_hw_unit_min, unit_limit);
lim->atomic_write_unit_max =
min(lim->atomic_write_hw_unit_max, unit_limit);
lim->atomic_write_boundary_sectors =
lim->atomic_write_hw_boundary >> SECTOR_SHIFT;
}
static void blk_validate_atomic_write_limits(struct queue_limits *lim)
{
unsigned int boundary_sectors;
if (!lim->atomic_write_hw_max)
goto unsupported;
boundary_sectors = lim->atomic_write_hw_boundary >> SECTOR_SHIFT;
if (boundary_sectors) {
/*
* A feature of boundary support is that it disallows bios to
* be merged which would result in a merged request which
* crosses either a chunk sector or atomic write HW boundary,
* even though chunk sectors may be just set for performance.
* For simplicity, disallow atomic writes for a chunk sector
* which is non-zero and smaller than atomic write HW boundary.
* Furthermore, chunk sectors must be a multiple of atomic
* write HW boundary. Otherwise boundary support becomes
* complicated.
* Devices which do not conform to these rules can be dealt
* with if and when they show up.
*/
if (WARN_ON_ONCE(lim->chunk_sectors % boundary_sectors))
goto unsupported;
/*
* The boundary size just needs to be a multiple of unit_max
* (and not necessarily a power-of-2), so this following check
* could be relaxed in future.
* Furthermore, if needed, unit_max could even be reduced so
* that it is compliant with a !power-of-2 boundary.
*/
if (!is_power_of_2(boundary_sectors))
goto unsupported;
}
blk_atomic_writes_update_limits(lim);
return;
unsupported:
lim->atomic_write_max_sectors = 0;
lim->atomic_write_boundary_sectors = 0;
lim->atomic_write_unit_min = 0;
lim->atomic_write_unit_max = 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;
int err;
/*
* 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;
else if (blk_validate_block_size(lim->logical_block_size)) {
pr_warn("Invalid logical block size (%d)\n", lim->logical_block_size);
return -EINVAL;
}
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 if (lim->io_opt > (BLK_DEF_MAX_SECTORS_CAP << SECTOR_SHIFT)) {
lim->max_sectors =
min(max_hw_sectors, lim->io_opt >> SECTOR_SHIFT);
} else if (lim->io_min > (BLK_DEF_MAX_SECTORS_CAP << SECTOR_SHIFT)) {
lim->max_sectors =
min(max_hw_sectors, lim->io_min >> SECTOR_SHIFT);
} 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->flags &= ~BLK_FLAG_MISALIGNED;
}
if (!(lim->features & BLK_FEAT_WRITE_CACHE))
lim->features &= ~BLK_FEAT_FUA;
blk_validate_atomic_write_limits(lim);
err = blk_validate_integrity_limits(lim);
if (err)
return err;
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)
{
int error;
error = blk_validate_limits(lim);
if (error)
goto out_unlock;
#ifdef CONFIG_BLK_INLINE_ENCRYPTION
if (q->crypto_profile && lim->integrity.tag_size) {
pr_warn("blk-integrity: Integrity and hardware inline encryption are not supported together.\n");
error = -EINVAL;
goto out_unlock;
}
#endif
q->limits = *lim;
if (q->disk)
blk_apply_bdi_limits(q->disk->bdi, lim);
out_unlock:
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_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_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->features |= (b->features & BLK_FEAT_INHERIT_MASK);
/*
* BLK_FEAT_NOWAIT and BLK_FEAT_POLL need to be supported both by the
* stacking driver and all underlying devices. The stacking driver sets
* the flags before stacking the limits, and this will clear the flags
* if any of the underlying devices does not support it.
*/
if (!(b->features & BLK_FEAT_NOWAIT))
t->features &= ~BLK_FEAT_NOWAIT;
if (!(b->features & BLK_FEAT_POLL))
t->features &= ~BLK_FEAT_POLL;
t->flags |= (b->flags & BLK_FLAG_MISALIGNED);
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->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);
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->flags |= BLK_FLAG_MISALIGNED;
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->flags |= BLK_FLAG_MISALIGNED;
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->flags |= BLK_FLAG_MISALIGNED;
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->flags |= BLK_FLAG_MISALIGNED;
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->flags |= BLK_FLAG_MISALIGNED;
ret = -1;
}
/* 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->flags |= BLK_FLAG_MISALIGNED;
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);
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);
if (!(t->features & BLK_FEAT_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);
/**
* queue_limits_stack_integrity - stack integrity profile
* @t: target queue limits
* @b: base queue limits
*
* Check if the integrity profile in the @b can be stacked into the
* target @t. Stacking is possible if either:
*
* a) does not have any integrity information stacked into it yet
* b) the integrity profile in @b is identical to the one in @t
*
* If @b can be stacked into @t, return %true. Else return %false and clear the
* integrity information in @t.
*/
bool queue_limits_stack_integrity(struct queue_limits *t,
struct queue_limits *b)
{
struct blk_integrity *ti = &t->integrity;
struct blk_integrity *bi = &b->integrity;
if (!IS_ENABLED(CONFIG_BLK_DEV_INTEGRITY))
return true;
if (!ti->tuple_size) {
/* inherit the settings from the first underlying device */
if (!(ti->flags & BLK_INTEGRITY_STACKED)) {
ti->flags = BLK_INTEGRITY_DEVICE_CAPABLE |
(bi->flags & BLK_INTEGRITY_REF_TAG);
ti->csum_type = bi->csum_type;
ti->tuple_size = bi->tuple_size;
ti->pi_offset = bi->pi_offset;
ti->interval_exp = bi->interval_exp;
ti->tag_size = bi->tag_size;
goto done;
}
if (!bi->tuple_size)
goto done;
}
if (ti->tuple_size != bi->tuple_size)
goto incompatible;
if (ti->interval_exp != bi->interval_exp)
goto incompatible;
if (ti->tag_size != bi->tag_size)
goto incompatible;
if (ti->csum_type != bi->csum_type)
goto incompatible;
if ((ti->flags & BLK_INTEGRITY_REF_TAG) !=
(bi->flags & BLK_INTEGRITY_REF_TAG))
goto incompatible;
done:
ti->flags |= BLK_INTEGRITY_STACKED;
return true;
incompatible:
memset(ti, 0, sizeof(*ti));
return false;
}
EXPORT_SYMBOL_GPL(queue_limits_stack_integrity);
/**
* 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);
int bdev_alignment_offset(struct block_device *bdev)
{
struct request_queue *q = bdev_get_queue(bdev);
if (q->limits.flags & BLK_FLAG_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);