IB/mlx4: Fix max_wqe capacity reported from query device
1. Limit the max number of WQEs per QP reported when querying the
device, so that ib_create_qp() will not fail for a QP size that the
device claimed to support due to additional headroom WQEs being
allocated.
2. Limit qp resources accepted for ib_create_qp() to the limits
reported in ib_query_device(). In kernel space, make sure that the
limits returned to the caller following qp creation also lie within
the reported device limits. For userspace, report as before, and do
adjustment in libmlx4 (so as not to break ABI).
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Sagi Grimberg <sagig@mellanox.co.il>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
diff --git a/drivers/infiniband/hw/mlx4/main.c b/drivers/infiniband/hw/mlx4/main.c
index 8afea12..3530c41 100644
--- a/drivers/infiniband/hw/mlx4/main.c
+++ b/drivers/infiniband/hw/mlx4/main.c
@@ -140,7 +140,7 @@
props->max_mr_size = ~0ull;
props->page_size_cap = dev->dev->caps.page_size_cap;
props->max_qp = dev->dev->caps.num_qps - dev->dev->caps.reserved_qps;
- props->max_qp_wr = dev->dev->caps.max_wqes;
+ props->max_qp_wr = dev->dev->caps.max_wqes - MLX4_IB_SQ_MAX_SPARE;
props->max_sge = min(dev->dev->caps.max_sq_sg,
dev->dev->caps.max_rq_sg);
props->max_cq = dev->dev->caps.num_cqs - dev->dev->caps.reserved_cqs;
diff --git a/drivers/infiniband/hw/mlx4/mlx4_ib.h b/drivers/infiniband/hw/mlx4/mlx4_ib.h
index e62297c..ff36655 100644
--- a/drivers/infiniband/hw/mlx4/mlx4_ib.h
+++ b/drivers/infiniband/hw/mlx4/mlx4_ib.h
@@ -44,6 +44,14 @@
#include <linux/mlx4/device.h>
#include <linux/mlx4/doorbell.h>
+enum {
+ MLX4_IB_SQ_MIN_WQE_SHIFT = 6,
+ MLX4_IB_MAX_HEADROOM = 2048
+};
+
+#define MLX4_IB_SQ_HEADROOM(shift) ((MLX4_IB_MAX_HEADROOM >> (shift)) + 1)
+#define MLX4_IB_SQ_MAX_SPARE (MLX4_IB_SQ_HEADROOM(MLX4_IB_SQ_MIN_WQE_SHIFT))
+
struct mlx4_ib_ucontext {
struct ib_ucontext ibucontext;
struct mlx4_uar uar;
diff --git a/drivers/infiniband/hw/mlx4/qp.c b/drivers/infiniband/hw/mlx4/qp.c
index ceb3332..8d4ed24 100644
--- a/drivers/infiniband/hw/mlx4/qp.c
+++ b/drivers/infiniband/hw/mlx4/qp.c
@@ -310,8 +310,8 @@
int is_user, int has_rq, struct mlx4_ib_qp *qp)
{
/* Sanity check RQ size before proceeding */
- if (cap->max_recv_wr > dev->dev->caps.max_wqes ||
- cap->max_recv_sge > dev->dev->caps.max_rq_sg)
+ if (cap->max_recv_wr > dev->dev->caps.max_wqes - MLX4_IB_SQ_MAX_SPARE ||
+ cap->max_recv_sge > min(dev->dev->caps.max_sq_sg, dev->dev->caps.max_rq_sg))
return -EINVAL;
if (!has_rq) {
@@ -329,8 +329,17 @@
qp->rq.wqe_shift = ilog2(qp->rq.max_gs * sizeof (struct mlx4_wqe_data_seg));
}
- cap->max_recv_wr = qp->rq.max_post = qp->rq.wqe_cnt;
- cap->max_recv_sge = qp->rq.max_gs;
+ /* leave userspace return values as they were, so as not to break ABI */
+ if (is_user) {
+ cap->max_recv_wr = qp->rq.max_post = qp->rq.wqe_cnt;
+ cap->max_recv_sge = qp->rq.max_gs;
+ } else {
+ cap->max_recv_wr = qp->rq.max_post =
+ min(dev->dev->caps.max_wqes - MLX4_IB_SQ_MAX_SPARE, qp->rq.wqe_cnt);
+ cap->max_recv_sge = min(qp->rq.max_gs,
+ min(dev->dev->caps.max_sq_sg,
+ dev->dev->caps.max_rq_sg));
+ }
return 0;
}
@@ -341,8 +350,8 @@
int s;
/* Sanity check SQ size before proceeding */
- if (cap->max_send_wr > dev->dev->caps.max_wqes ||
- cap->max_send_sge > dev->dev->caps.max_sq_sg ||
+ if (cap->max_send_wr > (dev->dev->caps.max_wqes - MLX4_IB_SQ_MAX_SPARE) ||
+ cap->max_send_sge > min(dev->dev->caps.max_sq_sg, dev->dev->caps.max_rq_sg) ||
cap->max_inline_data + send_wqe_overhead(type, qp->flags) +
sizeof (struct mlx4_wqe_inline_seg) > dev->dev->caps.max_sq_desc_sz)
return -EINVAL;