net/mlx5: Support new MR features

This patch adds the following items to IFC file.

1. MLX5_MKC_ACCESS_MODE_KSM enum value for creating KSM memory keys.
KSM access mode used when indirect MKey associated with fixed memory
size entries.

2. null_mkey field that is used to indicate non-present KLM/KSM
entries, where it causes the device to generate page fault event
when trying to access it.

3. struct mlx5_ifc_cmd_hca_cap_bits capability bits indicating
related value/field is supported:
* fixed_buffer_size - MLX5_MKC_ACCESS_MODE_KSM
* umr_extended_translation_offset - translation_offset_42_16
    in UMR ctrl segment
* null_mkey - null_mkey in QUERY_SPECIAL_CONTEXTS
Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/mlx5/mlx5_ifc.h

@@ -782,11 +782,12 @@ struct mlx5_ifc_cmd_hca_cap_bits {
 	u8         log_max_eq[0x4];
 
 	u8         max_indirection[0x8];
-	u8         reserved_at_108[0x1];
+	u8         fixed_buffer_size[0x1];
 	u8         log_max_mrw_sz[0x7];
 	u8         reserved_at_110[0x2];
 	u8         log_max_bsf_list_size[0x6];
-	u8         reserved_at_118[0x2];
+	u8         umr_extended_translation_offset[0x1];
+	u8         null_mkey[0x1];
 	u8         log_max_klm_list_size[0x6];
 
 	u8         reserved_at_120[0xa];
@@ -2569,6 +2570,7 @@ enum {
 	MLX5_MKC_ACCESS_MODE_PA    = 0x0,
 	MLX5_MKC_ACCESS_MODE_MTT   = 0x1,
 	MLX5_MKC_ACCESS_MODE_KLMS  = 0x2,
+	MLX5_MKC_ACCESS_MODE_KSM   = 0x3,
 };
 
 struct mlx5_ifc_mkc_bits {
@@ -3677,6 +3679,10 @@ struct mlx5_ifc_query_special_contexts_out_bits {
 	u8         dump_fill_mkey[0x20];
 
 	u8         resd_lkey[0x20];
+
+	u8         null_mkey[0x20];
+
+	u8         reserved_at_a0[0x60];
 };
 
 struct mlx5_ifc_query_special_contexts_in_bits {