net/mlx4_core: In SR-IOV mode host should add promisc QP to default entry only

In current situation host is adding the promiscuous QP to all steering
entries and the default entry as well. In this case when having PV
and SR-IOV on the same setup bridge will receive all traffic that is
targeted to the other VMs. This is bad.
Solution: In SR-IOV mode host can add promiscuous QP to default entry only.
The above problem and fix are relevant for B0 steering mode only.

Signed-off-by: Eugenia Emantayev <eugenia@mellanox.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/mellanox/mlx4/mcg.c b/drivers/net/ethernet/mellanox/mlx4/mcg.c
index 39ab85a..9d92bc2 100644
--- a/drivers/net/ethernet/mellanox/mlx4/mcg.c
+++ b/drivers/net/ethernet/mellanox/mlx4/mcg.c
@@ -433,43 +433,58 @@
 	}
 	mgm = mailbox->buf;
 
-	/* the promisc qp needs to be added for each one of the steering
-	 * entries, if it already exists, needs to be added as a duplicate
-	 * for this entry */
-	list_for_each_entry(entry, &s_steer->steer_entries[steer], list) {
-		err = mlx4_READ_ENTRY(dev, entry->index, mailbox);
-		if (err)
-			goto out_mailbox;
+	if (!(mlx4_is_mfunc(dev) && steer == MLX4_UC_STEER)) {
+		/* The promisc QP needs to be added for each one of the steering
+		 * entries. If it already exists, needs to be added as
+		 * a duplicate for this entry.
+		 */
+		list_for_each_entry(entry,
+				    &s_steer->steer_entries[steer],
+				    list) {
+			err = mlx4_READ_ENTRY(dev, entry->index, mailbox);
+			if (err)
+				goto out_mailbox;
 
-		members_count = be32_to_cpu(mgm->members_count) & 0xffffff;
-		prot = be32_to_cpu(mgm->members_count) >> 30;
-		found = false;
-		for (i = 0; i < members_count; i++) {
-			if ((be32_to_cpu(mgm->qp[i]) & MGM_QPN_MASK) == qpn) {
-				/* Entry already exists, add to duplicates */
-				dqp = kmalloc(sizeof *dqp, GFP_KERNEL);
-				if (!dqp) {
+			members_count = be32_to_cpu(mgm->members_count) &
+					0xffffff;
+			prot = be32_to_cpu(mgm->members_count) >> 30;
+			found = false;
+			for (i = 0; i < members_count; i++) {
+				if ((be32_to_cpu(mgm->qp[i]) &
+				     MGM_QPN_MASK) == qpn) {
+					/* Entry already exists.
+					 * Add to duplicates.
+					 */
+					dqp = kmalloc(sizeof(*dqp), GFP_KERNEL);
+					if (!dqp) {
+						err = -ENOMEM;
+						goto out_mailbox;
+					}
+					dqp->qpn = qpn;
+					list_add_tail(&dqp->list,
+						      &entry->duplicates);
+					found = true;
+				}
+			}
+			if (!found) {
+				/* Need to add the qpn to mgm */
+				if (members_count ==
+				    dev->caps.num_qp_per_mgm) {
+					/* entry is full */
 					err = -ENOMEM;
 					goto out_mailbox;
 				}
-				dqp->qpn = qpn;
-				list_add_tail(&dqp->list, &entry->duplicates);
-				found = true;
+				mgm->qp[members_count++] =
+					cpu_to_be32(qpn & MGM_QPN_MASK);
+				mgm->members_count =
+					cpu_to_be32(members_count |
+						    (prot << 30));
+				err = mlx4_WRITE_ENTRY(dev, entry->index,
+						       mailbox);
+				if (err)
+					goto out_mailbox;
 			}
 		}
-		if (!found) {
-			/* Need to add the qpn to mgm */
-			if (members_count == dev->caps.num_qp_per_mgm) {
-				/* entry is full */
-				err = -ENOMEM;
-				goto out_mailbox;
-			}
-			mgm->qp[members_count++] = cpu_to_be32(qpn & MGM_QPN_MASK);
-			mgm->members_count = cpu_to_be32(members_count | (prot << 30));
-			err = mlx4_WRITE_ENTRY(dev, entry->index, mailbox);
-			if (err)
-				goto out_mailbox;
-		}
 	}
 
 	/* add the new qpn to list of promisc qps */
@@ -556,51 +571,65 @@
 	if (err)
 		goto out_mailbox;
 
-	/* remove the qp from all the steering entries*/
-	list_for_each_entry(entry, &s_steer->steer_entries[steer], list) {
-		found = false;
-		list_for_each_entry(dqp, &entry->duplicates, list) {
-			if (dqp->qpn == qpn) {
-				found = true;
-				break;
-			}
-		}
-		if (found) {
-			/* a duplicate, no need to change the mgm,
-			 * only update the duplicates list */
-			list_del(&dqp->list);
-			kfree(dqp);
-		} else {
-			int loc = -1;
-			err = mlx4_READ_ENTRY(dev, entry->index, mailbox);
-				if (err)
-					goto out_mailbox;
-			members_count = be32_to_cpu(mgm->members_count) & 0xffffff;
-			for (i = 0; i < members_count; ++i)
-				if ((be32_to_cpu(mgm->qp[i]) &
-				     MGM_QPN_MASK) == qpn) {
-					loc = i;
+	if (!(mlx4_is_mfunc(dev) && steer == MLX4_UC_STEER)) {
+		/* remove the qp from all the steering entries*/
+		list_for_each_entry(entry,
+				    &s_steer->steer_entries[steer],
+				    list) {
+			found = false;
+			list_for_each_entry(dqp, &entry->duplicates, list) {
+				if (dqp->qpn == qpn) {
+					found = true;
 					break;
 				}
-
-			if (loc < 0) {
-				mlx4_err(dev, "QP %06x wasn't found in entry %d\n",
-					 qpn, entry->index);
-				err = -EINVAL;
-				goto out_mailbox;
 			}
+			if (found) {
+				/* A duplicate, no need to change the MGM,
+				 * only update the duplicates list
+				 */
+				list_del(&dqp->list);
+				kfree(dqp);
+			} else {
+				int loc = -1;
 
-			/* copy the last QP in this MGM over removed QP */
-			mgm->qp[loc] = mgm->qp[members_count - 1];
-			mgm->qp[members_count - 1] = 0;
-			mgm->members_count = cpu_to_be32(--members_count |
-							 (MLX4_PROT_ETH << 30));
+				err = mlx4_READ_ENTRY(dev,
+						      entry->index,
+						      mailbox);
+					if (err)
+						goto out_mailbox;
+				members_count =
+					be32_to_cpu(mgm->members_count) &
+					0xffffff;
+				for (i = 0; i < members_count; ++i)
+					if ((be32_to_cpu(mgm->qp[i]) &
+					     MGM_QPN_MASK) == qpn) {
+						loc = i;
+						break;
+					}
 
-			err = mlx4_WRITE_ENTRY(dev, entry->index, mailbox);
-				if (err)
+				if (loc < 0) {
+					mlx4_err(dev, "QP %06x wasn't found in entry %d\n",
+						 qpn, entry->index);
+					err = -EINVAL;
 					goto out_mailbox;
-		}
+				}
 
+				/* copy the last QP in this MGM
+				 * over removed QP
+				 */
+				mgm->qp[loc] = mgm->qp[members_count - 1];
+				mgm->qp[members_count - 1] = 0;
+				mgm->members_count =
+					cpu_to_be32(--members_count |
+						    (MLX4_PROT_ETH << 30));
+
+				err = mlx4_WRITE_ENTRY(dev,
+						       entry->index,
+						       mailbox);
+					if (err)
+						goto out_mailbox;
+			}
+		}
 	}
 
 out_mailbox: