[PATCH AUTOSEL 6.0 35/44] block: make dma_alignment a stacking queue_limit

From: Sasha Levin
Date: Wed Nov 23 2022 - 07:45:18 EST


From: Keith Busch <kbusch@xxxxxxxxxx>

[ Upstream commit c964d62f5cab7b43dd0534f22a96eab386c6ec5d ]

Device mappers had always been getting the default 511 dma mask, but
the underlying device might have a larger alignment requirement. Since
this value is used to determine alloweable direct-io alignment, this
needs to be a stackable limit.

Signed-off-by: Keith Busch <kbusch@xxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Link: https://lore.kernel.org/r/20221110184501.2451620-2-kbusch@xxxxxxxx
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
block/blk-core.c | 1 -
block/blk-settings.c | 8 +++++---
include/linux/blkdev.h | 15 ++++++++-------
3 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/block/blk-core.c b/block/blk-core.c
index 651057c4146b..2fbdf17f2206 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -426,7 +426,6 @@ struct request_queue *blk_alloc_queue(int node_id, bool alloc_srcu)
PERCPU_REF_INIT_ATOMIC, GFP_KERNEL))
goto fail_stats;

- blk_queue_dma_alignment(q, 511);
blk_set_default_limits(&q->limits);
q->nr_requests = BLKDEV_DEFAULT_RQ;

diff --git a/block/blk-settings.c b/block/blk-settings.c
index 8bb9eef5310e..4949ed3ce7c9 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -57,6 +57,7 @@ void blk_set_default_limits(struct queue_limits *lim)
lim->misaligned = 0;
lim->zoned = BLK_ZONED_NONE;
lim->zone_write_granularity = 0;
+ lim->dma_alignment = 511;
}
EXPORT_SYMBOL(blk_set_default_limits);

@@ -600,6 +601,7 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,

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)
@@ -773,7 +775,7 @@ EXPORT_SYMBOL(blk_queue_virt_boundary);
**/
void blk_queue_dma_alignment(struct request_queue *q, int mask)
{
- q->dma_alignment = mask;
+ q->limits.dma_alignment = mask;
}
EXPORT_SYMBOL(blk_queue_dma_alignment);

@@ -795,8 +797,8 @@ void blk_queue_update_dma_alignment(struct request_queue *q, int mask)
{
BUG_ON(mask > PAGE_SIZE);

- if (mask > q->dma_alignment)
- q->dma_alignment = mask;
+ if (mask > q->limits.dma_alignment)
+ q->limits.dma_alignment = mask;
}
EXPORT_SYMBOL(blk_queue_update_dma_alignment);

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 84b13fdd34a7..79624711fda7 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -311,6 +311,13 @@ struct queue_limits {
unsigned char discard_misaligned;
unsigned char raid_partial_stripes_expensive;
enum blk_zoned_model zoned;
+
+ /*
+ * Drivers that set dma_alignment to less than 511 must be prepared to
+ * handle individual bvec's that are not a multiple of a SECTOR_SIZE
+ * due to possible offsets.
+ */
+ unsigned int dma_alignment;
};

typedef int (*report_zones_cb)(struct blk_zone *zone, unsigned int idx,
@@ -456,12 +463,6 @@ struct request_queue {
unsigned long nr_requests; /* Max # of requests */

unsigned int dma_pad_mask;
- /*
- * Drivers that set dma_alignment to less than 511 must be prepared to
- * handle individual bvec's that are not a multiple of a SECTOR_SIZE
- * due to possible offsets.
- */
- unsigned int dma_alignment;

#ifdef CONFIG_BLK_INLINE_ENCRYPTION
struct blk_crypto_profile *crypto_profile;
@@ -1311,7 +1312,7 @@ static inline sector_t bdev_zone_sectors(struct block_device *bdev)

static inline int queue_dma_alignment(const struct request_queue *q)
{
- return q ? q->dma_alignment : 511;
+ return q ? q->limits.dma_alignment : 511;
}

static inline unsigned int bdev_dma_alignment(struct block_device *bdev)
--
2.35.1