Test that
+ Invalid inputs should be rejected with EINVAL + Successful inputs return a new (destination) fd + Destination and source fds have the same inode number + No crash on program exit
Signed-off-by: Ackerley Tng ackerleytng@google.com --- .../testing/selftests/kvm/guest_memfd_test.c | 42 +++++++++++++++++++ .../selftests/kvm/include/kvm_util_base.h | 18 ++++++++ 2 files changed, 60 insertions(+)
diff --git a/tools/testing/selftests/kvm/guest_memfd_test.c b/tools/testing/selftests/kvm/guest_memfd_test.c index ad20f11b2d2c..38fe96ea60f9 100644 --- a/tools/testing/selftests/kvm/guest_memfd_test.c +++ b/tools/testing/selftests/kvm/guest_memfd_test.c @@ -105,6 +105,47 @@ static void test_create_guest_memfd_invalid(struct kvm_vm *vm, size_t page_size) ASSERT_EQ(errno, EINVAL); }
+static void test_link(struct kvm_vm *src_vm, int src_fd, size_t total_size) +{ + int ret; + int dst_fd; + struct kvm_vm *dst_vm; + struct stat src_stat; + struct stat dst_stat; + + dst_vm = vm_create_barebones(); + + /* Linking with a nonexistent fd */ + dst_fd = __vm_link_guest_memfd(dst_vm, 99, 0); + ASSERT_EQ(dst_fd, -1); + ASSERT_EQ(errno, EINVAL); + + /* Linking with a non-gmem fd */ + dst_fd = __vm_link_guest_memfd(dst_vm, 0, 1); + ASSERT_EQ(dst_fd, -1); + ASSERT_EQ(errno, EINVAL); + + /* Linking with invalid flags */ + dst_fd = __vm_link_guest_memfd(dst_vm, src_fd, 1); + ASSERT_EQ(dst_fd, -1); + ASSERT_EQ(errno, EINVAL); + + /* Linking with an already-associated vm */ + dst_fd = __vm_link_guest_memfd(src_vm, src_fd, 1); + ASSERT_EQ(dst_fd, -1); + ASSERT_EQ(errno, EINVAL); + + dst_fd = __vm_link_guest_memfd(dst_vm, src_fd, 0); + TEST_ASSERT(dst_vm > 0, "linking should succeed with valid inputs"); + TEST_ASSERT(src_fd != dst_fd, "linking should return a different fd"); + + ret = fstat(src_fd, &src_stat); + ASSERT_EQ(ret, 0); + ret = fstat(dst_fd, &dst_stat); + ASSERT_EQ(ret, 0); + TEST_ASSERT(src_stat.st_ino == dst_stat.st_ino, + "src and dst files should have the same inode number"); +}
int main(int argc, char *argv[]) { @@ -126,6 +167,7 @@ int main(int argc, char *argv[]) test_mmap(fd, page_size); test_file_size(fd, page_size, total_size); test_fallocate(fd, page_size, total_size); + test_link(vm, fd, total_size);
close(fd); } diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h index 8bdfadd72349..868925b26a7b 100644 --- a/tools/testing/selftests/kvm/include/kvm_util_base.h +++ b/tools/testing/selftests/kvm/include/kvm_util_base.h @@ -495,6 +495,24 @@ static inline int vm_create_guest_memfd(struct kvm_vm *vm, uint64_t size, return fd; }
+static inline int __vm_link_guest_memfd(struct kvm_vm *vm, int fd, uint64_t flags) +{ + struct kvm_link_guest_memfd params = { + .fd = fd, + .flags = flags, + }; + + return __vm_ioctl(vm, KVM_LINK_GUEST_MEMFD, ¶ms); +} + +static inline int vm_link_guest_memfd(struct kvm_vm *vm, int fd, uint64_t flags) +{ + int new_fd = __vm_link_guest_memfd(vm, fd, flags); + + TEST_ASSERT(new_fd >= 0, KVM_IOCTL_ERROR(KVM_LINK_GUEST_MEMFD, new_fd)); + return new_fd; +} + void vm_set_user_memory_region(struct kvm_vm *vm, uint32_t slot, uint32_t flags, uint64_t gpa, uint64_t size, void *hva); int __vm_set_user_memory_region(struct kvm_vm *vm, uint32_t slot, uint32_t flags,