[RFC PATCH v3 23/31] KVM: selftests: Add functions to allow mapping as shared

[Ackerley Tng <ackerleytng@google.com>]

Signed-off-by: Ackerley Tng <ackerleytng@google.com>
---
 .../selftests/kvm/include/kvm_util_base.h     | 24 ++++++++++++++
 tools/testing/selftests/kvm/lib/kvm_util.c    | 32 +++++++++++++++++++
 .../selftests/kvm/lib/x86_64/processor.c      | 15 +++++++--
 3 files changed, 69 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h
index cdc204cfeb4c2..30453e2de8396 100644
--- a/tools/testing/selftests/kvm/include/kvm_util_base.h
+++ b/tools/testing/selftests/kvm/include/kvm_util_base.h
@@ -412,6 +412,8 @@ vm_vaddr_t vm_vaddr_alloc_page(struct kvm_vm *vm);
 
 void virt_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
 	      unsigned int npages);
+void virt_map_shared(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
+		     unsigned int npages);
 void *addr_gpa2hva(struct kvm_vm *vm, vm_paddr_t gpa);
 void *addr_gva2hva(struct kvm_vm *vm, vm_vaddr_t gva);
 vm_paddr_t addr_hva2gpa(struct kvm_vm *vm, void *hva);
@@ -843,6 +845,28 @@ static inline void virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr
 	virt_arch_pg_map(vm, vaddr, paddr);
 }
 
+/*
+ * VM Virtual Page Map as Shared
+ *
+ * Input Args:
+ *   vm - Virtual Machine
+ *   vaddr - VM Virtual Address
+ *   paddr - VM Physical Address
+ *   memslot - Memory region slot for new virtual translation tables
+ *
+ * Output Args: None
+ *
+ * Return: None
+ *
+ * Within @vm, creates a virtual translation for the page starting
+ * at @vaddr to the page starting at @paddr.
+ */
+void virt_arch_pg_map_shared(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr);
+
+static inline void virt_pg_map_shared(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr)
+{
+	virt_arch_pg_map_shared(vm, vaddr, paddr);
+}
 
 /*
  * Address Guest Virtual to Guest Physical
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index 14246f0fd2e78..6673be2f49c31 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -1384,6 +1384,38 @@ void virt_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
 	}
 }
 
+/*
+ * Map a range of VM virtual address to the VM's physical address as shared
+ *
+ * Input Args:
+ *   vm - Virtual Machine
+ *   vaddr - Virtuall address to map
+ *   paddr - VM Physical Address
+ *   npages - The number of pages to map
+ *
+ * Output Args: None
+ *
+ * Return: None
+ *
+ * Within the VM given by @vm, creates a virtual translation for
+ * @npages starting at @vaddr to the page range starting at @paddr.
+ */
+void virt_map_shared(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
+		     unsigned int npages)
+{
+	size_t page_size = vm->page_size;
+	size_t size = npages * page_size;
+
+	TEST_ASSERT(vaddr + size > vaddr, "Vaddr overflow");
+	TEST_ASSERT(paddr + size > paddr, "Paddr overflow");
+
+	while (npages--) {
+		virt_pg_map_shared(vm, vaddr, paddr);
+		vaddr += page_size;
+		paddr += page_size;
+	}
+}
+
 /*
  * Address VM Physical to Host Virtual
  *
diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
index 1ea1019d48c13..b4c18f7335dab 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -176,7 +176,8 @@ static uint64_t *virt_create_upper_pte(struct kvm_vm *vm,
 	return pte;
 }
 
-void __virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr, int level)
+static void ___virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
+			   int level, bool protected)
 {
 	const uint64_t pg_size = PG_LEVEL_SIZE(level);
 	uint64_t *pml4e, *pdpe, *pde;
@@ -223,17 +224,27 @@ void __virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr, int level)
 		    "PTE already present for 4k page at vaddr: 0x%lx\n", vaddr);
 	*pte = PTE_PRESENT_MASK | PTE_WRITABLE_MASK | (paddr & PHYSICAL_PAGE_MASK);
 
-	if (vm_is_gpa_protected(vm, paddr))
+	if (protected)
 		*pte |= vm->arch.c_bit;
 	else
 		*pte |= vm->arch.s_bit;
 }
 
+void __virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr, int level)
+{
+	___virt_pg_map(vm, vaddr, paddr, level, vm_is_gpa_protected(vm, paddr));
+}
+
 void virt_arch_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr)
 {
 	__virt_pg_map(vm, vaddr, paddr, PG_LEVEL_4K);
 }
 
+void virt_arch_pg_map_shared(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr)
+{
+	___virt_pg_map(vm, vaddr, paddr, PG_LEVEL_4K, false);
+}
+
 void virt_map_level(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
 		    uint64_t nr_bytes, int level)
 {
-- 
2.39.0.246.g2a6d74b583-goog