From: Nikita Kalyazin kalyazin@amazon.com
This is to reflect that the write syscall is now implemented for guest_memfd.
Signed-off-by: Nikita Kalyazin kalyazin@amazon.com --- .../testing/selftests/kvm/guest_memfd_test.c | 86 +++++++++++++++++-- 1 file changed, 80 insertions(+), 6 deletions(-)
diff --git a/tools/testing/selftests/kvm/guest_memfd_test.c b/tools/testing/selftests/kvm/guest_memfd_test.c index b3ca6737f304..1236e31f5041 100644 --- a/tools/testing/selftests/kvm/guest_memfd_test.c +++ b/tools/testing/selftests/kvm/guest_memfd_test.c @@ -24,18 +24,91 @@ #include "test_util.h" #include "ucall_common.h"
-static void test_file_read_write(int fd) +static void test_file_read(int fd) { char buf[64];
TEST_ASSERT(read(fd, buf, sizeof(buf)) < 0, "read on a guest_mem fd should fail"); - TEST_ASSERT(write(fd, buf, sizeof(buf)) < 0, - "write on a guest_mem fd should fail"); TEST_ASSERT(pread(fd, buf, sizeof(buf), 0) < 0, "pread on a guest_mem fd should fail"); - TEST_ASSERT(pwrite(fd, buf, sizeof(buf), 0) < 0, - "pwrite on a guest_mem fd should fail"); +} + +static void test_file_write(int fd, size_t total_size) +{ + size_t page_size = getpagesize(); + void *buf = NULL; + int ret; + + ret = posix_memalign(&buf, page_size, total_size); + TEST_ASSERT_EQ(ret, 0); + + /* Check arguments correctness checks work as expected */ + + ret = pwrite(fd, buf, page_size - 1, 0); + TEST_ASSERT(ret == -1, "write unaligned count on a guest_mem fd should fail"); + TEST_ASSERT_EQ(errno, EINVAL); + + ret = pwrite(fd, buf, page_size, 1); + TEST_ASSERT(ret == -1, "write unaligned offset on a guest_mem fd should fail"); + TEST_ASSERT_EQ(errno, EINVAL); + + ret = pwrite(fd, buf, page_size, total_size); + TEST_ASSERT(ret == -1, "writing past the file size on a guest_mem fd should fail"); + TEST_ASSERT_EQ(errno, EINVAL); + + ret = pwrite(fd, NULL, page_size, 0); + TEST_ASSERT(ret == -1, "supplying a NULL buffer when writing a guest_mem fd should fail"); + TEST_ASSERT_EQ(errno, EFAULT); + + /* Check double population is not allowed */ + + ret = pwrite(fd, buf, page_size, 0); + TEST_ASSERT(ret == page_size, "page-aligned write on a guest_mem fd should succeed"); + + ret = pwrite(fd, buf, page_size, 0); + TEST_ASSERT(ret == -1, "write on already populated guest_mem fd should fail"); + TEST_ASSERT_EQ(errno, ENOSPC); + + ret = fallocate(fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE, 0, page_size); + TEST_ASSERT(!ret, "fallocate(PUNCH_HOLE) should succeed"); + + /* Check population is allowed again after punching a hole */ + + ret = pwrite(fd, buf, page_size, 0); + TEST_ASSERT(ret == page_size, + "page-aligned write on a punched guest_mem fd should succeed"); + + ret = fallocate(fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE, 0, page_size); + TEST_ASSERT(!ret, "fallocate(PUNCH_HOLE) should succeed"); + + /* Check population of already allocated memory is allowed */ + + ret = fallocate(fd, FALLOC_FL_KEEP_SIZE, 0, page_size); + TEST_ASSERT(!ret, "fallocate with aligned offset and size should succeed"); + + ret = pwrite(fd, buf, page_size, 0); + TEST_ASSERT(ret == page_size, "write on a preallocated guest_mem fd should succeed"); + + ret = fallocate(fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE, 0, page_size); + TEST_ASSERT(!ret, "fallocate(PUNCH_HOLE) should succeed"); + + /* Check population works until an already populated page is encountered */ + + ret = pwrite(fd, buf, total_size, 0); + TEST_ASSERT(ret == total_size, "page-aligned write on a guest_mem fd should succeed"); + + ret = fallocate(fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE, 0, page_size); + TEST_ASSERT(!ret, "fallocate(PUNCH_HOLE) should succeed"); + + ret = pwrite(fd, buf, total_size, 0); + TEST_ASSERT(ret == page_size, "write on a guest_mem fd should not overwrite data"); + + ret = fallocate(fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE, 0, total_size); + TEST_ASSERT(!ret, "fallocate(PUNCH_HOLE) should succeed"); + + + free(buf); }
static void test_mmap_supported(int fd, size_t page_size, size_t total_size) @@ -281,7 +354,8 @@ static void test_guest_memfd(unsigned long vm_type)
fd = vm_create_guest_memfd(vm, total_size, flags);
- test_file_read_write(fd); + test_file_read(fd); + test_file_write(fd, total_size);
if (flags & GUEST_MEMFD_FLAG_MMAP) { test_mmap_supported(fd, page_size, total_size);