mlx4_core: calculate log_num_mtt based on total system memory

The SR-IOV shared-port mechanism has a limitation that all the resources
and qp contexts are proxied through the PF. In order to reflect the
supported mtt entries, the log_num_mtt must be calculated based on the host
system memory rather than the privileged domain system memory. Thus, this
patch performs a Xen specific call to obtain the total memory during the PF
driver loading and uses that info to determine the size of the mtt table.

Orabug: 26526968

Signed-off-by: Wei Lin Guay <wei.lin.guay@oracle.com>
Signed-off-by: Ajaykumar Hotchandani <ajaykumar.hotchandani@oracle.com>
Reviewed-by: Avinash Repaka <avinash.repaka@oracle.com>
Reviewed-by: Håkon Bugge <haakon.bugge@oracle.com>

diff --git a/drivers/net/ethernet/mellanox/mlx4/main.c b/drivers/net/ethernet/mellanox/mlx4/main.c
index a64ced2ed8ca5026cd226a1f4dbc2af8057f29d8..111639cf7f8d36d156e6498a01c8def79f5766cc 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/main.c
+++ b/drivers/net/ethernet/mellanox/mlx4/main.c
@@ -232,7 +232,7 @@ enum {
        MLX4_IF_STATE_EXTENDED
 };
 
-static void process_mod_param_profile(struct mlx4_profile *profile)
+static void process_mod_param_profile(struct mlx4_profile *profile, struct mlx4_dev *dev)
 {
        struct sysinfo si;
 
@@ -353,7 +353,20 @@ static void process_mod_param_profile(struct mlx4_profile *profile)
                        pr_warn("mlx4_core: Both scale_profile and log_num_mtt are set. Ignore scale_profile.\n");
                profile->num_mtt_segs = 1 << mod_param_profile.num_mtt_segs;
        } else {
+               unsigned long totalram_pages = 0;
+               int ret;
+
                si_meminfo(&si);
+               totalram_pages = si.totalram;
+
+               if (mlx4_is_master(dev)) {
+                       ret = xen_get_host_pages(&totalram_pages);
+                       if (ret) {
+                               totalram_pages = si.totalram;
+                               mlx4_warn(dev, "mlx4_core: xen_get_host_pages failed ret = %d \n!", ret);
+                       }
+               }
+
                profile->num_mtt_segs =
                        roundup_pow_of_two(max_t(unsigned,
                                                1 << (MLX4_LOG_NUM_MTT -
@@ -361,7 +374,7 @@ static void process_mod_param_profile(struct mlx4_profile *profile)
                                                min(1UL <<
                                                (MLX4_MAX_LOG_NUM_MTT -
                                                log_mtts_per_seg),
-                                               (si.totalram << 1)
+                                               (totalram_pages << 1)
                                                >> log_mtts_per_seg)));
                /* set the actual value, so it will be reflected to the user
                   using the sysfs */
@@ -2246,7 +2259,7 @@ static int mlx4_init_hca(struct mlx4_dev *dev)
                        mlx4_info(dev, "Running from within kdump kernel. Using low memory profile\n");
                        profile = low_mem_profile;
                } else {
-                       process_mod_param_profile(&profile);
+                       process_mod_param_profile(&profile, dev);
                }
                if (dev->caps.steering_mode ==
                    MLX4_STEERING_MODE_DEVICE_MANAGED)