hv: add APIs to allow updating EPT mem type

- Add PAGING_REQUEST_TYPE_MODIFY_MT memory map request type
- Update map_mem_region() to allow modifying the memory type related
  fields in a page table entry
- Add ept_update_mt()
- add modify_mem_mt() for both EPT and MMU

Signed-off-by: Zide Chen <zide.chen@intel.com>
Reviewed-by: Jason Chen CJ <jason.cj.chen@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>

hypervisor/arch/x86/ept.c

@@ -489,3 +489,24 @@ int ept_mmap(struct vm *vm, uint64_t hpa,
 
 	return 0;
 }
+
+int ept_update_mt(struct vm *vm, uint64_t hpa,
+	uint64_t gpa, uint64_t size, uint32_t prot)
+{
+	struct map_params map_params;
+	struct vcpu *vcpu;
+	int i;
+
+	/* Setup memory map parameters */
+	map_params.page_table_type = PTT_EPT;
+	map_params.pml4_base = HPA2HVA(vm->arch_vm.nworld_eptp);
+	map_params.pml4_inverted = HPA2HVA(vm->arch_vm.m2p);
+
+	modify_mem_mt(&map_params, (void *)hpa, (void *)gpa, size, prot);
+
+	foreach_vcpu(i, vm, vcpu) {
+		vcpu_make_request(vcpu, ACRN_REQUEST_EPT_FLUSH);
+	}
+
+	return 0;
+}

hypervisor/arch/x86/mmu.c

@@ -35,6 +35,7 @@ enum mem_map_request_type {
 	PAGING_REQUEST_TYPE_MAP = 0,	/* Creates a new mapping. */
 	PAGING_REQUEST_TYPE_UNMAP = 1,	/* Removes a pre-existing entry */
 	PAGING_REQUEST_TYPE_MODIFY = 2,
+	PAGING_REQUEST_TYPE_MODIFY_MT = 3, /* Update the memory type fields */
 	/* Modifies a pre-existing entries attributes. */
 	PAGING_REQUEST_TYPE_UNKNOWN,
 };
@@ -375,6 +376,28 @@ static uint32_t map_mem_region(void *vaddr, void *paddr,
 				mmu_need_invtlb = true;
 			break;
 		}
+		case PAGING_REQUEST_TYPE_MODIFY_MT:
+		{
+			if (prev_entry_present) {
+				/* modify the memory type related fields only */
+				if (table_type == PTT_EPT)
+					table_entry = entry & ~IA32E_EPT_MT_MASK;
+				else
+					table_entry = entry & ~MMU_MEM_ATTR_TYPE_MASK;
+
+				table_entry |= attr;
+
+				/* Write the table entry to map this memory */
+				MEM_WRITE64(table_base + table_offset, table_entry);
+
+				/* Modify, need to invalidate TLB and
+				 * page-structure cache
+				 */
+				if (table_type == PTT_HOST)
+					mmu_need_invtlb = true;
+			}
+			break;
+		}
 		default:
 			ASSERT(0, "Bad memory map request type");
 			return 0;
@@ -1124,3 +1147,23 @@ int modify_mem(struct map_params *map_params, void *paddr, void *vaddr,
 	}
 	return ret;
 }
+
+int modify_mem_mt(struct map_params *map_params, void *paddr, void *vaddr,
+		    uint64_t size, uint32_t flags)
+{
+	int ret = 0;
+
+	/* used for MMU and EPT*/
+	ret = modify_paging(map_params, paddr, vaddr, size, flags,
+			PAGING_REQUEST_TYPE_MODIFY_MT, true);
+	if (ret < 0)
+		return ret;
+
+	/* only for EPT */
+	if (map_params->page_table_type == PTT_EPT) {
+		ret = modify_paging(map_params, vaddr, paddr, size, flags,
+				PAGING_REQUEST_TYPE_MODIFY_MT, false);
+	}
+	return ret;
+}
+

hypervisor/include/arch/x86/mmu.h

@@ -28,6 +28,7 @@
 #define     IA32E_EPT_WT                    (4<<3)
 #define     IA32E_EPT_WP                    (5<<3)
 #define     IA32E_EPT_WB                    (6<<3)
+#define     IA32E_EPT_MT_MASK               (7<<3)
 #define     IA32E_EPT_PAT_IGNORE            0x0000000000000040
 #define     IA32E_EPT_ACCESS_FLAG           0x0000000000000100
 #define     IA32E_EPT_DIRTY_FLAG            0x0000000000000200
@@ -216,6 +217,9 @@
 /* Selects PAT7 WP  */
 #define     MMU_MEM_ATTR_TYPE_WRITE_PROTECTED \
 		(IA32E_PDPTE_PAT_BIT | IA32E_COMM_PCD_BIT | IA32E_COMM_PWT_BIT)
+/* memory type bits mask */
+#define     MMU_MEM_ATTR_TYPE_MASK \
+		(IA32E_PDPTE_PAT_BIT | IA32E_COMM_PCD_BIT | IA32E_COMM_PWT_BIT)
 
 #define ROUND_PAGE_UP(addr)  (((addr) + CPU_PAGE_SIZE - 1) & CPU_PAGE_MASK)
 #define ROUND_PAGE_DOWN(addr) ((addr) & CPU_PAGE_MASK)
@@ -302,6 +306,8 @@ int unmap_mem(struct map_params *map_params, void *paddr, void *vaddr,
 		      uint64_t size, uint32_t flags);
 int modify_mem(struct map_params *map_params, void *paddr, void *vaddr,
 		       uint64_t size, uint32_t flags);
+int modify_mem_mt(struct map_params *map_params, void *paddr, void *vaddr,
+		       uint64_t size, uint32_t flags);
 int check_vmx_mmu_cap(void);
 int allocate_vpid(void);
 void flush_vpid_single(int vpid);
@@ -375,6 +381,8 @@ uint64_t _gpa2hpa(struct vm *vm, uint64_t gpa, uint32_t *size);
 uint64_t  hpa2gpa(struct vm *vm, uint64_t hpa);
 int ept_mmap(struct vm *vm, uint64_t hpa,
 	uint64_t gpa, uint64_t size, uint32_t type, uint32_t prot);
+int ept_update_mt(struct vm *vm, uint64_t hpa,
+	uint64_t gpa, uint64_t size, uint32_t prot);
 
 int     ept_violation_vmexit_handler(struct vcpu *vcpu);
 int     ept_misconfig_vmexit_handler(struct vcpu *vcpu);