aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/infiniband/core/uverbs_cmd.c
diff options
context:
space:
mode:
authorSteve Wise <swise@opengridcomputing.com>2018-06-18 08:05:26 -0700
committerJason Gunthorpe <jgg@mellanox.com>2018-06-18 13:17:28 -0600
commit33023fb85a42b53bf778bc025f9667b582282be4 (patch)
tree66d55701f7cc41636dcfc4353e38b4262791b47f /drivers/infiniband/core/uverbs_cmd.c
parentIB/rxe: avoid unnecessary NULL check (diff)
downloadlinux-dev-33023fb85a42b53bf778bc025f9667b582282be4.tar.xz
linux-dev-33023fb85a42b53bf778bc025f9667b582282be4.zip
IB/core: add max_send_sge and max_recv_sge attributes
This patch replaces the ib_device_attr.max_sge with max_send_sge and max_recv_sge. It allows ulps to take advantage of devices that have very different send and recv sge depths. For example cxgb4 has a max_recv_sge of 4, yet a max_send_sge of 16. Splitting out these attributes allows much more efficient use of the SQ for cxgb4 with ulps that use the RDMA_RW API. Consider a large RDMA WRITE that has 16 scattergather entries. With max_sge of 4, the ulp would send 4 WRITE WRs, but with max_sge of 16, it can be done with 1 WRITE WR. Acked-by: Sagi Grimberg <sagi@grimberg.me> Acked-by: Christoph Hellwig <hch@lst.de> Acked-by: Selvin Xavier <selvin.xavier@broadcom.com> Acked-by: Shiraz Saleem <shiraz.saleem@intel.com> Acked-by: Dennis Dalessandro <dennis.dalessandro@intel.com> Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Diffstat (limited to 'drivers/infiniband/core/uverbs_cmd.c')
-rw-r--r--drivers/infiniband/core/uverbs_cmd.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c
index 5733d0fb0673..908ee8ab3297 100644
--- a/drivers/infiniband/core/uverbs_cmd.c
+++ b/drivers/infiniband/core/uverbs_cmd.c
@@ -189,7 +189,7 @@ static void copy_query_dev_fields(struct ib_uverbs_file *file,
resp->max_qp = attr->max_qp;
resp->max_qp_wr = attr->max_qp_wr;
resp->device_cap_flags = lower_32_bits(attr->device_cap_flags);
- resp->max_sge = attr->max_sge;
+ resp->max_sge = min(attr->max_send_sge, attr->max_recv_sge);
resp->max_sge_rd = attr->max_sge_rd;
resp->max_cq = attr->max_cq;
resp->max_cqe = attr->max_cqe;