IB/core: Enhance ib_map_mr_sg()
The SRP initiator allows to set max_sectors to a value that exceeds
the largest amount of data that can be mapped at once with an mlx4
HCA using fast registration and a page size of 4 KB. Hence modify
ib_map_mr_sg() such that it can map partial sg-elements. If an
sg-element has been mapped partially, let the caller know
which fraction has been mapped by adjusting *sg_offset.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Tested-by: Laurence Oberman <loberman@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Doug Ledford <dledford@redhat.com>
diff --git a/drivers/infiniband/hw/mlx5/mr.c b/drivers/infiniband/hw/mlx5/mr.c
index b678eac..8cf2ce5 100644
--- a/drivers/infiniband/hw/mlx5/mr.c
+++ b/drivers/infiniband/hw/mlx5/mr.c
@@ -1752,10 +1752,11 @@
mlx5_ib_sg_to_klms(struct mlx5_ib_mr *mr,
struct scatterlist *sgl,
unsigned short sg_nents,
- unsigned int sg_offset)
+ unsigned int *sg_offset_p)
{
struct scatterlist *sg = sgl;
struct mlx5_klm *klms = mr->descs;
+ unsigned int sg_offset = sg_offset_p ? *sg_offset_p : 0;
u32 lkey = mr->ibmr.pd->local_dma_lkey;
int i;
@@ -1774,6 +1775,9 @@
sg_offset = 0;
}
+ if (sg_offset_p)
+ *sg_offset_p = sg_offset;
+
return i;
}
@@ -1792,7 +1796,7 @@
}
int mlx5_ib_map_mr_sg(struct ib_mr *ibmr, struct scatterlist *sg, int sg_nents,
- unsigned int sg_offset)
+ unsigned int *sg_offset)
{
struct mlx5_ib_mr *mr = to_mmr(ibmr);
int n;