1 files changed, 91 insertions, 78 deletions

diff --git a/tools/testing/selftests/kvm/guest_memfd_test.c b/tools/testing/selftests/kvm/guest_memfd_test.c
index b3ca6737f304..e7d9aeb418d3 100644
--- a/tools/testing/selftests/kvm/guest_memfd_test.c
+++ b/tools/testing/selftests/kvm/guest_memfd_test.c
@@ -14,8 +14,6 @@
 #include <linux/bitmap.h>
 #include <linux/falloc.h>
 #include <linux/sizes.h>
-#include <setjmp.h>
-#include <signal.h>
 #include <sys/mman.h>
 #include <sys/types.h>
 #include <sys/stat.h>
@@ -24,7 +22,9 @@
 #include "test_util.h"
 #include "ucall_common.h"
 
-static void test_file_read_write(int fd)
+static size_t page_size;
+
+static void test_file_read_write(int fd, size_t total_size)
 {
 	char buf[64];
 
@@ -38,18 +38,22 @@ static void test_file_read_write(int fd)
 		    "pwrite on a guest_mem fd should fail");
 }
 
-static void test_mmap_supported(int fd, size_t page_size, size_t total_size)
+static void test_mmap_cow(int fd, size_t size)
+{
+	void *mem;
+
+	mem = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
+	TEST_ASSERT(mem == MAP_FAILED, "Copy-on-write not allowed by guest_memfd.");
+}
+
+static void test_mmap_supported(int fd, size_t total_size)
 {
 	const char val = 0xaa;
 	char *mem;
 	size_t i;
 	int ret;
 
-	mem = mmap(NULL, total_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
-	TEST_ASSERT(mem == MAP_FAILED, "Copy-on-write not allowed by guest_memfd.");
-
-	mem = mmap(NULL, total_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
-	TEST_ASSERT(mem != MAP_FAILED, "mmap() for guest_memfd should succeed.");
+	mem = kvm_mmap(total_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd);
 
 	memset(mem, val, total_size);
 	for (i = 0; i < total_size; i++)
@@ -68,45 +72,37 @@ static void test_mmap_supported(int fd, size_t page_size, size_t total_size)
 	for (i = 0; i < total_size; i++)
 		TEST_ASSERT_EQ(READ_ONCE(mem[i]), val);
 
-	ret = munmap(mem, total_size);
-	TEST_ASSERT(!ret, "munmap() should succeed.");
-}
-
-static sigjmp_buf jmpbuf;
-void fault_sigbus_handler(int signum)
-{
-	siglongjmp(jmpbuf, 1);
+	kvm_munmap(mem, total_size);
 }
 
-static void test_fault_overflow(int fd, size_t page_size, size_t total_size)
+static void test_fault_sigbus(int fd, size_t accessible_size, size_t map_size)
 {
-	struct sigaction sa_old, sa_new = {
-		.sa_handler = fault_sigbus_handler,
-	};
-	size_t map_size = total_size * 4;
 	const char val = 0xaa;
 	char *mem;
 	size_t i;
-	int ret;
 
-	mem = mmap(NULL, map_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
-	TEST_ASSERT(mem != MAP_FAILED, "mmap() for guest_memfd should succeed.");
+	mem = kvm_mmap(map_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd);
 
-	sigaction(SIGBUS, &sa_new, &sa_old);
-	if (sigsetjmp(jmpbuf, 1) == 0) {
-		memset(mem, 0xaa, map_size);
-		TEST_ASSERT(false, "memset() should have triggered SIGBUS.");
-	}
-	sigaction(SIGBUS, &sa_old, NULL);
+	TEST_EXPECT_SIGBUS(memset(mem, val, map_size));
+	TEST_EXPECT_SIGBUS((void)READ_ONCE(mem[accessible_size]));
 
-	for (i = 0; i < total_size; i++)
+	for (i = 0; i < accessible_size; i++)
 		TEST_ASSERT_EQ(READ_ONCE(mem[i]), val);
 
-	ret = munmap(mem, map_size);
-	TEST_ASSERT(!ret, "munmap() should succeed.");
+	kvm_munmap(mem, map_size);
+}
+
+static void test_fault_overflow(int fd, size_t total_size)
+{
+	test_fault_sigbus(fd, total_size, total_size * 4);
+}
+
+static void test_fault_private(int fd, size_t total_size)
+{
+	test_fault_sigbus(fd, 0, total_size);
 }
 
-static void test_mmap_not_supported(int fd, size_t page_size, size_t total_size)
+static void test_mmap_not_supported(int fd, size_t total_size)
 {
 	char *mem;
 
@@ -117,7 +113,7 @@ static void test_mmap_not_supported(int fd, size_t page_size, size_t total_size)
 	TEST_ASSERT_EQ(mem, MAP_FAILED);
 }
 
-static void test_file_size(int fd, size_t page_size, size_t total_size)
+static void test_file_size(int fd, size_t total_size)
 {
 	struct stat sb;
 	int ret;
@@ -128,7 +124,7 @@ static void test_file_size(int fd, size_t page_size, size_t total_size)
 	TEST_ASSERT_EQ(sb.st_blksize, page_size);
 }
 
-static void test_fallocate(int fd, size_t page_size, size_t total_size)
+static void test_fallocate(int fd, size_t total_size)
 {
 	int ret;
 
@@ -165,7 +161,7 @@ static void test_fallocate(int fd, size_t page_size, size_t total_size)
 	TEST_ASSERT(!ret, "fallocate to restore punched hole should succeed");
 }
 
-static void test_invalid_punch_hole(int fd, size_t page_size, size_t total_size)
+static void test_invalid_punch_hole(int fd, size_t total_size)
 {
 	struct {
 		off_t offset;
@@ -196,8 +192,7 @@ static void test_invalid_punch_hole(int fd, size_t page_size, size_t total_size)
 }
 
 static void test_create_guest_memfd_invalid_sizes(struct kvm_vm *vm,
-						  uint64_t guest_memfd_flags,
-						  size_t page_size)
+						  uint64_t guest_memfd_flags)
 {
 	size_t size;
 	int fd;
@@ -214,7 +209,6 @@ static void test_create_guest_memfd_multiple(struct kvm_vm *vm)
 {
 	int fd1, fd2, ret;
 	struct stat st1, st2;
-	size_t page_size = getpagesize();
 
 	fd1 = __vm_create_guest_memfd(vm, page_size, 0);
 	TEST_ASSERT(fd1 != -1, "memfd creation should succeed");
@@ -239,9 +233,9 @@ static void test_create_guest_memfd_multiple(struct kvm_vm *vm)
 	close(fd1);
 }
 
-static void test_guest_memfd_flags(struct kvm_vm *vm, uint64_t valid_flags)
+static void test_guest_memfd_flags(struct kvm_vm *vm)
 {
-	size_t page_size = getpagesize();
+	uint64_t valid_flags = vm_check_cap(vm, KVM_CAP_GUEST_MEMFD_FLAGS);
 	uint64_t flag;
 	int fd;
 
@@ -260,43 +254,57 @@ static void test_guest_memfd_flags(struct kvm_vm *vm, uint64_t valid_flags)
 	}
 }
 
-static void test_guest_memfd(unsigned long vm_type)
+#define gmem_test(__test, __vm, __flags)				\
+do {									\
+	int fd = vm_create_guest_memfd(__vm, page_size * 4, __flags);	\
+									\
+	test_##__test(fd, page_size * 4);				\
+	close(fd);							\
+} while (0)
+
+static void __test_guest_memfd(struct kvm_vm *vm, uint64_t flags)
 {
-	uint64_t flags = 0;
-	struct kvm_vm *vm;
-	size_t total_size;
-	size_t page_size;
-	int fd;
+	test_create_guest_memfd_multiple(vm);
+	test_create_guest_memfd_invalid_sizes(vm, flags);
 
-	page_size = getpagesize();
-	total_size = page_size * 4;
+	gmem_test(file_read_write, vm, flags);
 
-	vm = vm_create_barebones_type(vm_type);
+	if (flags & GUEST_MEMFD_FLAG_MMAP) {
+		if (flags & GUEST_MEMFD_FLAG_INIT_SHARED) {
+			gmem_test(mmap_supported, vm, flags);
+			gmem_test(fault_overflow, vm, flags);
+		} else {
+			gmem_test(fault_private, vm, flags);
+		}
 
-	if (vm_check_cap(vm, KVM_CAP_GUEST_MEMFD_MMAP))
-		flags |= GUEST_MEMFD_FLAG_MMAP;
+		gmem_test(mmap_cow, vm, flags);
+	} else {
+		gmem_test(mmap_not_supported, vm, flags);
+	}
 
-	test_create_guest_memfd_multiple(vm);
-	test_create_guest_memfd_invalid_sizes(vm, flags, page_size);
+	gmem_test(file_size, vm, flags);
+	gmem_test(fallocate, vm, flags);
+	gmem_test(invalid_punch_hole, vm, flags);
+}
 
-	fd = vm_create_guest_memfd(vm, total_size, flags);
+static void test_guest_memfd(unsigned long vm_type)
+{
+	struct kvm_vm *vm = vm_create_barebones_type(vm_type);
+	uint64_t flags;
 
-	test_file_read_write(fd);
+	test_guest_memfd_flags(vm);
 
-	if (flags & GUEST_MEMFD_FLAG_MMAP) {
-		test_mmap_supported(fd, page_size, total_size);
-		test_fault_overflow(fd, page_size, total_size);
-	} else {
-		test_mmap_not_supported(fd, page_size, total_size);
-	}
+	__test_guest_memfd(vm, 0);
 
-	test_file_size(fd, page_size, total_size);
-	test_fallocate(fd, page_size, total_size);
-	test_invalid_punch_hole(fd, page_size, total_size);
+	flags = vm_check_cap(vm, KVM_CAP_GUEST_MEMFD_FLAGS);
+	if (flags & GUEST_MEMFD_FLAG_MMAP)
+		__test_guest_memfd(vm, GUEST_MEMFD_FLAG_MMAP);
 
-	test_guest_memfd_flags(vm, flags);
+	/* MMAP should always be supported if INIT_SHARED is supported. */
+	if (flags & GUEST_MEMFD_FLAG_INIT_SHARED)
+		__test_guest_memfd(vm, GUEST_MEMFD_FLAG_MMAP |
+				       GUEST_MEMFD_FLAG_INIT_SHARED);
 
-	close(fd);
 	kvm_vm_free(vm);
 }
 
@@ -328,22 +336,26 @@ static void test_guest_memfd_guest(void)
 	size_t size;
 	int fd, i;
 
-	if (!kvm_has_cap(KVM_CAP_GUEST_MEMFD_MMAP))
+	if (!kvm_check_cap(KVM_CAP_GUEST_MEMFD_FLAGS))
 		return;
 
 	vm = __vm_create_shape_with_one_vcpu(VM_SHAPE_DEFAULT, &vcpu, 1, guest_code);
 
-	TEST_ASSERT(vm_check_cap(vm, KVM_CAP_GUEST_MEMFD_MMAP),
-		    "Default VM type should always support guest_memfd mmap()");
+	TEST_ASSERT(vm_check_cap(vm, KVM_CAP_GUEST_MEMFD_FLAGS) & GUEST_MEMFD_FLAG_MMAP,
+		    "Default VM type should support MMAP, supported flags = 0x%x",
+		    vm_check_cap(vm, KVM_CAP_GUEST_MEMFD_FLAGS));
+	TEST_ASSERT(vm_check_cap(vm, KVM_CAP_GUEST_MEMFD_FLAGS) & GUEST_MEMFD_FLAG_INIT_SHARED,
+		    "Default VM type should support INIT_SHARED, supported flags = 0x%x",
+		    vm_check_cap(vm, KVM_CAP_GUEST_MEMFD_FLAGS));
 
 	size = vm->page_size;
-	fd = vm_create_guest_memfd(vm, size, GUEST_MEMFD_FLAG_MMAP);
+	fd = vm_create_guest_memfd(vm, size, GUEST_MEMFD_FLAG_MMAP |
+					     GUEST_MEMFD_FLAG_INIT_SHARED);
 	vm_set_user_memory_region2(vm, slot, KVM_MEM_GUEST_MEMFD, gpa, size, NULL, fd, 0);
 
-	mem = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
-	TEST_ASSERT(mem != MAP_FAILED, "mmap() on guest_memfd failed");
+	mem = kvm_mmap(size, PROT_READ | PROT_WRITE, MAP_SHARED, fd);
 	memset(mem, 0xaa, size);
-	munmap(mem, size);
+	kvm_munmap(mem, size);
 
 	virt_pg_map(vm, gpa, gpa);
 	vcpu_args_set(vcpu, 2, gpa, size);
@@ -351,8 +363,7 @@ static void test_guest_memfd_guest(void)
 
 	TEST_ASSERT_EQ(get_ucall(vcpu, NULL), UCALL_DONE);
 
-	mem = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
-	TEST_ASSERT(mem != MAP_FAILED, "mmap() on guest_memfd failed");
+	mem = kvm_mmap(size, PROT_READ | PROT_WRITE, MAP_SHARED, fd);
 	for (i = 0; i < size; i++)
 		TEST_ASSERT_EQ(mem[i], 0xff);
 
@@ -366,6 +377,8 @@ int main(int argc, char *argv[])
 
 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_GUEST_MEMFD));
 
+	page_size = getpagesize();
+
 	/*
 	 * Not all architectures support KVM_CAP_VM_TYPES. However, those that
 	 * support guest_memfd have that support for the default VM type.