IB/mlx4: Fix possible vl/sl field mismatch in LRH header in QP1 packets

In MLX qp packets, the LRH (built by the driver) has both a VL field
and an SL field. When building a QP1 packet, the VL field should
reflect the SLtoVL mapping and not arbitrarily contain zero (as is
done now). This bug causes credit problems in IB switches at
high rates of QP1 packets.

The fix is to cache the SL to VL mapping in the driver, and look up
the VL mapped to the SL provided in the send request when sending
QP1 packets.

For FW versions which support generating a port_management_config_change
event with subtype sl-to-vl-table-change, the driver uses that event
to update its sl-to-vl mapping cache.  Otherwise, the driver snoops
incoming SMP mads to update the cache.

There remains the case where the FW is running in secure-host mode
(so no QP0 packets are delivered to the driver), and the FW does not
generate the sl2vl mapping change event. To support this case, the
driver updates (via querying the FW) its sl2vl mapping cache when
running in secure-host mode when it receives either a Port Up event
or a client-reregister event (where the port is still up, but there
may have been an opensm failover).
OpenSM modifies the sl2vl mapping before Port Up and Client-reregister
events occur, so if there is a mapping change the driver's cache will
be properly updated.

Fixes: 225c7b1feef1 ("IB/mlx4: Add a driver Mellanox ConnectX InfiniBand adapters")
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

1 files changed, 9 insertions, 4 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx4/fw.c b/drivers/net/ethernet/mellanox/mlx4/fw.c
index d728704d0c7b..d87bbe65c2b0 100644
--- a/drivers/net/ethernet/mellanox/mlx4/fw.c
+++ b/drivers/net/ethernet/mellanox/mlx4/fw.c
@@ -158,7 +158,8 @@ static void dump_dev_cap_flags2(struct mlx4_dev *dev, u64 flags)
 		[31] = "Modifying loopback source checks using UPDATE_QP support",
 		[32] = "Loopback source checks support",
 		[33] = "RoCEv2 support",
-		[34] = "DMFS Sniffer support (UC & MC)"
+		[34] = "DMFS Sniffer support (UC & MC)",
+		[36] = "sl to vl mapping table change event support"
 	};
 	int i;
 
@@ -703,6 +704,7 @@ int mlx4_QUERY_DEV_CAP(struct mlx4_dev *dev, struct mlx4_dev_cap *dev_cap)
 #define QUERY_DEV_CAP_FLOW_STEERING_IPOIB_OFFSET	0x74
 #define QUERY_DEV_CAP_FLOW_STEERING_RANGE_EN_OFFSET	0x76
 #define QUERY_DEV_CAP_FLOW_STEERING_MAX_QP_OFFSET	0x77
+#define QUERY_DEV_CAP_SL2VL_EVENT_OFFSET	0x78
 #define QUERY_DEV_CAP_CQ_EQ_CACHE_LINE_STRIDE	0x7a
 #define QUERY_DEV_CAP_ECN_QCN_VER_OFFSET	0x7b
 #define QUERY_DEV_CAP_RDMARC_ENTRY_SZ_OFFSET	0x80
@@ -822,6 +824,9 @@ int mlx4_QUERY_DEV_CAP(struct mlx4_dev *dev, struct mlx4_dev_cap *dev_cap)
 		dev_cap->flags2 |= MLX4_DEV_CAP_FLAG2_DMFS_IPOIB;
 	MLX4_GET(field, outbox, QUERY_DEV_CAP_FLOW_STEERING_MAX_QP_OFFSET);
 	dev_cap->fs_max_num_qp_per_entry = field;
+	MLX4_GET(field, outbox, QUERY_DEV_CAP_SL2VL_EVENT_OFFSET);
+	if (field & (1 << 5))
+		dev_cap->flags2 |= MLX4_DEV_CAP_FLAG2_SL_TO_VL_CHANGE_EVENT;
 	MLX4_GET(field, outbox, QUERY_DEV_CAP_ECN_QCN_VER_OFFSET);
 	if (field & 0x1)
 		dev_cap->flags2 |= MLX4_DEV_CAP_FLAG2_QCN;
@@ -2698,7 +2703,6 @@ static int mlx4_check_smp_firewall_active(struct mlx4_dev *dev,
 int mlx4_config_mad_demux(struct mlx4_dev *dev)
 {
 	struct mlx4_cmd_mailbox *mailbox;
-	int secure_host_active;
 	int err;
 
 	/* Check if mad_demux is supported */
@@ -2721,7 +2725,8 @@ int mlx4_config_mad_demux(struct mlx4_dev *dev)
 		goto out;
 	}
 
-	secure_host_active = mlx4_check_smp_firewall_active(dev, mailbox);
+	if (mlx4_check_smp_firewall_active(dev, mailbox))
+		dev->flags |= MLX4_FLAG_SECURE_HOST;
 
 	/* Config mad_demux to handle all MADs returned by the query above */
 	err = mlx4_cmd(dev, mailbox->dma, 0x01 /* subn mgmt class */,
@@ -2732,7 +2737,7 @@ int mlx4_config_mad_demux(struct mlx4_dev *dev)
 		goto out;
 	}
 
-	if (secure_host_active)
+	if (dev->flags & MLX4_FLAG_SECURE_HOST)
 		mlx4_warn(dev, "HCA operating in secure-host mode. SMP firewall activated.\n");
 out:
 	mlx4_free_cmd_mailbox(dev, mailbox);