mlx4_core: Get the maximum message size from reported device capabilities

Get the maximum message size from the device capabilities returned
from the QUERY_DEV_CAP firmware command, rather than hard-coding 2 GB.

Signed-off-by: Dotan Barak <dotanb@dev.mellanox.co.il>
Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

diff --git a/drivers/infiniband/hw/mlx4/main.c b/drivers/infiniband/hw/mlx4/main.c
index c591616..2fc8cce 100644
--- a/drivers/infiniband/hw/mlx4/main.c
+++ b/drivers/infiniband/hw/mlx4/main.c
@@ -169,7 +169,7 @@
 	props->phys_state	= out_mad->data[33] >> 4;
 	props->port_cap_flags	= be32_to_cpup((__be32 *) (out_mad->data + 20));
 	props->gid_tbl_len	= to_mdev(ibdev)->dev->caps.gid_table_len[port];
-	props->max_msg_sz	= 0x80000000;
+	props->max_msg_sz	= to_mdev(ibdev)->dev->caps.max_msg_sz;
 	props->pkey_tbl_len	= to_mdev(ibdev)->dev->caps.pkey_table_len[port];
 	props->bad_pkey_cntr	= be16_to_cpup((__be16 *) (out_mad->data + 46));
 	props->qkey_viol_cntr	= be16_to_cpup((__be16 *) (out_mad->data + 48));