mshv: add function to query vmm capabilities

Use the passthrough hvcall IOCTL on the /dev/mshv fd to perform a
self query for VMM capabilities.

Signed-off-by: Anirudh Rayabharam <[email protected]>

Author: anirudhrb

hv-headers/hvgdk_mini.h

@@ -173,6 +173,7 @@ struct hv_u128 {
 #define HVCALL_COMPLETE_ISOLATED_IMPORT		0x00f1
 #define HVCALL_ISSUE_SNP_PSP_GUEST_REQUEST	0x00f2
 #define HVCALL_GET_VP_CPUID_VALUES		0x00f4
+#define HVCALL_GET_PARTITION_PROPERTY_EX	0x0101
 
 /* HvFlushGuestPhysicalAddressList, HvExtCallMemoryHeatHint hypercall */
 union hv_gpa_page_range {

hv-headers/hvhdk.h

@@ -471,6 +471,42 @@ struct hv_input_set_partition_property {
 	__u64 property_value;
 } __packed;
 
+union hv_partition_property_arg {
+	__u64 as_uint64;
+	struct {
+		union {
+			__u32 arg;
+			__u32 vp_index;
+		};
+		__u16 reserved0;
+		__u8 reserved1;
+		__u8 object_type;
+	};
+} __packed;
+
+struct hv_input_get_partition_property_ex {
+	__u64 partition_id;
+	__u32 property_code; /* enum hv_partition_property_code */
+	__u32 padding;
+	union {
+		union hv_partition_property_arg arg_data;
+		__u64 arg;
+	};
+} __packed;
+
+#define HV_PARTITION_PROPERTY_EX_MAX_VAR_SIZE \
+	(HV_HYP_PAGE_SIZE - sizeof(struct hv_input_get_partition_property_ex))
+
+union hv_partition_property_ex {
+	__u8 buffer[HV_PARTITION_PROPERTY_EX_MAX_VAR_SIZE];
+	struct hv_partition_property_vmm_capabilities vmm_capabilities;
+	/* More fields to be filled in when needed */
+} __packed;
+
+struct hv_output_get_partition_property_ex {
+	union hv_partition_property_ex property_value;
+} __packed;
+
 struct hv_cpuid_leaf_info {
 	__u32 eax;
 	__u32 ecx;

hv-headers/hvhdk_mini.h

@@ -88,8 +88,14 @@ enum hv_partition_property_code {
 
     /* Nested virtualization properties */
     HV_PARTITION_PROPERTY_PROCESSOR_VIRTUALIZATION_FEATURES	= 0x00080000,
+
+    /* Extended properties with larger property values */
+    HV_PARTITION_PROPERTY_VMM_CAPABILITIES              = 0x00090007,
 };
 
+#define HV_PARTITION_VMM_CAPABILITIES_BANK_COUNT	1
+#define HV_PARTITION_VMM_CAPABILITIES_RESERVED_BITFIELD_COUNT	59
+
 /* HV Map GPA (Guest Physical Address) Flags */
 #define HV_MAP_GPA_PERMISSIONS_NONE	       0x0
 #define HV_MAP_GPA_READABLE		       0x1
@@ -164,4 +170,24 @@ struct hv_input_complete_isolated_import {
 	union hv_partition_complete_isolated_import_data import_data;
 } __packed;
 
+struct hv_partition_property_vmm_capabilities {
+	__u16 bank_count;
+	__u16 reserved[3];
+	union {
+		__u64 as_uint64[HV_PARTITION_VMM_CAPABILITIES_BANK_COUNT];
+		struct {
+			__u64 map_gpa_preserve_adjustable : 1;
+			__u64 vmm_can_provide_overlay_gpfn : 1;
+			__u64 vp_affinity_property : 1;
+#if defined(__aarch64__)
+			__u64 vmm_can_provide_gic_overlay_locations : 1;
+#else
+			__u64 reservedbit3 : 1;
+#endif
+			__u64 assignable_synthetic_proc_features : 1;
+			__u64 reserved0 : HV_PARTITION_VMM_CAPABILITIES_RESERVED_BITFIELD_COUNT;
+		} __packed;
+	};
+} __packed;
+
 #endif /* _HVHDK_MINI_H */