IB/mthca: max_inline_data handling tweaks

Fix a case where copying max_inline_data from a successful create_qp
capabilities output to create_qp input could cause EINVAL error:

mthca_set_qp_size must check max_inline_data directly against
max_desc_sz; checking qp->sq.max_gs is wrong since max_inline_data
depends on the qp type and does not involve max_sg.

Signed-off-by: Jack Morgenstein <jackm@mellanox.co.il>
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 36 insertions, 26 deletions

diff --git a/drivers/infiniband/hw/mthca/mthca_qp.c b/drivers/infiniband/hw/mthca/mthca_qp.c
index ea45fa400fab..fd60cf3a5ba3 100644
--- a/drivers/infiniband/hw/mthca/mthca_qp.c
+++ b/drivers/infiniband/hw/mthca/mthca_qp.c
@@ -890,18 +890,13 @@ int mthca_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr, int attr_mask)
         return err;
 }
 
-static void mthca_adjust_qp_caps(struct mthca_dev *dev,
-                                 struct mthca_pd *pd,
-                                 struct mthca_qp *qp)
+static int mthca_max_data_size(struct mthca_dev *dev, struct mthca_qp *qp, int desc_sz)
 {
-        int max_data_size;
-
         /*
          * Calculate the maximum size of WQE s/g segments, excluding
          * the next segment and other non-data segments.
          */
-        max_data_size = min(dev->limits.max_desc_sz, 1 << qp->sq.wqe_shift) -
-                sizeof (struct mthca_next_seg);
+        int max_data_size = desc_sz - sizeof (struct mthca_next_seg);
 
         switch (qp->transport) {
         case MLX:
@@ -920,11 +915,24 @@ static void mthca_adjust_qp_caps(struct mthca_dev *dev,
                 break;
         }
 
+        return max_data_size;
+}
+
+static inline int mthca_max_inline_data(struct mthca_pd *pd, int max_data_size)
+{
         /* We don't support inline data for kernel QPs (yet). */
-        if (!pd->ibpd.uobject)
-                qp->max_inline_data = 0;
-        else
-                qp->max_inline_data = max_data_size - MTHCA_INLINE_HEADER_SIZE;
+        return pd->ibpd.uobject ? max_data_size - MTHCA_INLINE_HEADER_SIZE : 0;
+}
+
+static void mthca_adjust_qp_caps(struct mthca_dev *dev,
+                                 struct mthca_pd *pd,
+                                 struct mthca_qp *qp)
+{
+        int max_data_size = mthca_max_data_size(dev, qp,
+                                                min(dev->limits.max_desc_sz,
+                                                    1 << qp->sq.wqe_shift));
+
+        qp->max_inline_data = mthca_max_inline_data(pd, max_data_size);
 
         qp->sq.max_gs = min_t(int, dev->limits.max_sg,
                               max_data_size / sizeof (struct mthca_data_seg));
@@ -1191,13 +1199,23 @@ static int mthca_alloc_qp_common(struct mthca_dev *dev,
 }
 
 static int mthca_set_qp_size(struct mthca_dev *dev, struct ib_qp_cap *cap,
-                             struct mthca_qp *qp)
+                             struct mthca_pd *pd, struct mthca_qp *qp)
 {
+        int max_data_size = mthca_max_data_size(dev, qp, dev->limits.max_desc_sz);
+
         /* Sanity check QP size before proceeding */
-        if (cap->max_send_wr  > dev->limits.max_wqes ||
-            cap->max_recv_wr  > dev->limits.max_wqes ||
-            cap->max_send_sge > dev->limits.max_sg   ||
-            cap->max_recv_sge > dev->limits.max_sg)
+        if (cap->max_send_wr     > dev->limits.max_wqes ||
+            cap->max_recv_wr     > dev->limits.max_wqes ||
+            cap->max_send_sge    > dev->limits.max_sg   ||
+            cap->max_recv_sge    > dev->limits.max_sg   ||
+            cap->max_inline_data > mthca_max_inline_data(pd, max_data_size))
+                return -EINVAL;
+
+        /*
+         * For MLX transport we need 2 extra S/G entries:
+         * one for the header and one for the checksum at the end
+         */
+        if (qp->transport == MLX && cap->max_recv_sge + 2 > dev->limits.max_sg)
                 return -EINVAL;
 
         if (mthca_is_memfree(dev)) {
@@ -1216,14 +1234,6 @@ static int mthca_set_qp_size(struct mthca_dev *dev, struct ib_qp_cap *cap,
                                     MTHCA_INLINE_CHUNK_SIZE) /
                               sizeof (struct mthca_data_seg));
 
-        /*
-         * For MLX transport we need 2 extra S/G entries:
-         * one for the header and one for the checksum at the end
-         */
-        if ((qp->transport == MLX && qp->sq.max_gs + 2 > dev->limits.max_sg) ||
-            qp->sq.max_gs > dev->limits.max_sg || qp->rq.max_gs > dev->limits.max_sg)
-                return -EINVAL;
-
         return 0;
 }
 
@@ -1238,7 +1248,7 @@ int mthca_alloc_qp(struct mthca_dev *dev,
 {
         int err;
 
-        err = mthca_set_qp_size(dev, cap, qp);
+        err = mthca_set_qp_size(dev, cap, pd, qp);
         if (err)
                 return err;
 
@@ -1281,7 +1291,7 @@ int mthca_alloc_sqp(struct mthca_dev *dev,
         u32 mqpn = qpn * 2 + dev->qp_table.sqp_start + port - 1;
         int err;
 
-        err = mthca_set_qp_size(dev, cap, &sqp->qp);
+        err = mthca_set_qp_size(dev, cap, pd, &sqp->qp);
         if (err)
                 return err;