RDMA drivers need segments that aren't larger than a single HCA page
for memory registrations to work properly, so wire up this limitation
in the host.
While we could just call blk_queue_max_segment_size from ->slave_configure,
that would override the global limit based on the DMA device, so let's do
it the traditional way by adding a field to the Scsi_Host structure.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
drivers/scsi/scsi_lib.c | 3 ++-
include/scsi/scsi_host.h | 1 +
2 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 8106515..04c660d 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -2120,7 +2120,8 @@ static void __scsi_init_queue(struct Scsi_Host *shost, struct request_queue *q)
blk_queue_segment_boundary(q, shost->dma_boundary);
dma_set_seg_boundary(dev, shost->dma_boundary);
- blk_queue_max_segment_size(q, dma_get_max_seg_size(dev));
+ blk_queue_max_segment_size(q,
+ min(shost->max_segment_size, dma_get_max_seg_size(dev)));
if (!shost->use_clustering)
q->limits.cluster = 0;
diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h
index fcfa3d7..f11d3fe 100644
--- a/include/scsi/scsi_host.h
+++ b/include/scsi/scsi_host.h
@@ -621,6 +621,7 @@ struct Scsi_Host {
short unsigned int sg_tablesize;
short unsigned int sg_prot_tablesize;
unsigned int max_sectors;
+ unsigned int max_segment_size;
unsigned long dma_boundary;
/*
* In scsi-mq mode, the number of hardware queues supported by the LLD.
--
2.1.4
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