scsi: core: Add a dma_alignment field to the host and host template

Get drivers out of the business of having to call the block layer DMA
alignment limits helpers themselves.

Signed-off-by: Christoph Hellwig <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Bart Van Assche <[email protected]>
Reviewed-by: John Garry <[email protected]>
Reviewed-by: Damien Le Moal <[email protected]>
Reviewed-by: Hannes Reinecke <[email protected]>
Reviewed-by: Johannes Thumshirn <[email protected]>
Acked-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

1 files changed, 2 insertions, 9 deletions

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index f1936f98abe3..26b51406c477 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1985,15 +1985,8 @@ void scsi_init_limits(struct Scsi_Host *shost, struct queue_limits *lim)
 	lim->seg_boundary_mask = shost->dma_boundary;
 	lim->max_segment_size = shost->max_segment_size;
 	lim->virt_boundary_mask = shost->virt_boundary_mask;
-
-	/*
-	 * Set a reasonable default alignment:  The larger of 32-byte (dword),
-	 * which is a common minimum for HBAs, and the minimum DMA alignment,
-	 * which is set by the platform.
-	 *
-	 * Devices that require a bigger alignment can increase it later.
-	 */
-	lim->dma_alignment = max(4, dma_get_cache_alignment()) - 1;
+	lim->dma_alignment = max_t(unsigned int,
+		shost->dma_alignment, dma_get_cache_alignment() - 1);
 
 	if (shost->no_highmem)
 		lim->bounce = BLK_BOUNCE_HIGH;