hv: ept: add lookup_address to lookup the page table

Add lookup_address to lokup the page table for a virtual address
of primary page table or a physical address of extended page table.
The remaining obtain_last_page_table_entry could be removed with their
called function later.

Signed-off-by: Li, Fei1 <fei1.li@intel.com>

Author: lifeix

hypervisor/arch/x86/ept.c

@@ -120,26 +120,21 @@ void destroy_ept(struct vm *vm)
 uint64_t _gpa2hpa(struct vm *vm, uint64_t gpa, uint32_t *size)
 {
 	uint64_t hpa = 0UL;
-	uint32_t pg_size = 0U;
-	struct entry_params entry;
-	struct map_params map_params;
+	uint64_t *pgentry, pg_size = 0UL;
 
-	map_params.page_table_type = PTT_EPT;
-	map_params.pml4_base = vm->arch_vm.nworld_eptp;
-	map_params.pml4_inverted = vm->arch_vm.m2p;
-	obtain_last_page_table_entry(&map_params, &entry, (void *)gpa, true);
-	if (entry.entry_present == PT_PRESENT) {
-		hpa = ((entry.entry_val & (~(entry.page_size - 1)))
-				| (gpa & (entry.page_size - 1)));
-		pg_size = entry.page_size;
+	pgentry = lookup_address((uint64_t *)vm->arch_vm.nworld_eptp,
+			gpa, &pg_size, PTT_EPT);
+	if (pgentry != NULL) {
+		hpa = ((*pgentry & (~(pg_size - 1UL)))
+				| (gpa & (pg_size - 1UL)));
 		pr_dbg("GPA2HPA: 0x%llx->0x%llx", gpa, hpa);
 	} else {
 		pr_err("VM %d GPA2HPA: failed for gpa 0x%llx",
 				vm->attr.boot_idx, gpa);
 	}
 
 	if (size != NULL) {
-		*size = pg_size;
+		*size = (uint32_t)pg_size;
 	}
 
 	return hpa;
@@ -153,23 +148,17 @@ uint64_t gpa2hpa(struct vm *vm, uint64_t gpa)
 
 uint64_t hpa2gpa(struct vm *vm, uint64_t hpa)
 {
-	struct entry_params entry;
-	struct map_params map_params;
-
-	map_params.page_table_type = PTT_EPT;
-	map_params.pml4_base = vm->arch_vm.nworld_eptp;
-	map_params.pml4_inverted = vm->arch_vm.m2p;
-
-	obtain_last_page_table_entry(&map_params, &entry,
-			(void *)hpa, false);
+	uint64_t *pgentry, pg_size = 0UL;
 
-	if (entry.entry_present == PT_NOT_PRESENT) {
+	pgentry = lookup_address((uint64_t *)vm->arch_vm.m2p,
+			hpa, &pg_size, PTT_EPT);
+	if (pgentry == NULL) {
 		pr_err("VM %d hpa2gpa: failed for hpa 0x%llx",
 				vm->attr.boot_idx, hpa);
 		ASSERT(false, "hpa2gpa not found");
 	}
-	return ((entry.entry_val & (~(entry.page_size - 1)))
-			| (hpa & (entry.page_size - 1)));
+	return ((*pgentry & (~(pg_size - 1UL)))
+			| (hpa & (pg_size - 1UL)));
 }
 
 bool is_ept_supported(void)

hypervisor/arch/x86/pagetable.c

@@ -452,3 +452,42 @@ int mmu_add(uint64_t *pml4_page, uint64_t paddr_base,
 
 	return 0;
 }
+
+uint64_t *lookup_address(uint64_t *pml4_page,
+		uint64_t addr, uint64_t *pg_size, enum _page_table_type ptt)
+{
+	uint64_t *pml4e, *pdpte, *pde, *pte;
+
+	if ((pml4_page == NULL) || (pg_size == NULL)) {
+		return NULL;
+	}
+
+	pml4e = pml4e_offset(pml4_page, addr);
+	if (pgentry_present(ptt, *pml4e) == 0UL) {
+		return NULL;
+	}
+
+	pdpte = pdpte_offset(pml4e, addr);
+	if (pgentry_present(ptt, *pdpte) == 0UL) {
+		return NULL;
+	} else if (pdpte_large(*pdpte) != 0UL) {
+		*pg_size = PDPTE_SIZE;
+		return pdpte;
+	}
+
+	pde = pde_offset(pdpte, addr);
+	if (pgentry_present(ptt, *pde) == 0UL) {
+		return NULL;
+	} else if (pde_large(*pde) != 0UL) {
+		*pg_size = PDE_SIZE;
+		return pde;
+	}
+
+	pte = pte_offset(pde, addr);
+	if (pgentry_present(ptt, *pte) == 0UL) {
+		return NULL;
+	} else {
+		*pg_size = PTE_SIZE;
+		return pte;
+	}
+}

hypervisor/include/arch/x86/mmu.h

@@ -339,6 +339,8 @@ void invept(struct vcpu *vcpu);
 bool check_continuous_hpa(struct vm *vm, uint64_t gpa_arg, uint64_t size_arg);
 int obtain_last_page_table_entry(struct map_params *map_params,
 		struct entry_params *entry, void *addr, bool direct);
+uint64_t *lookup_address(uint64_t *pml4_page, uint64_t addr,
+		uint64_t *pg_size, enum _page_table_type ptt);
 
 int register_mmio_emulation_handler(struct vm *vm,
 	hv_mem_io_handler_t read_write, uint64_t start,