Sean Christopherson <seanjc@xxxxxxxxxx> writes: > Add a selftest to verify the basic functionality of guest_memfd(): > > + file descriptor created with the guest_memfd() ioctl does not allow > read/write/mmap operations > + file size and block size as returned from fstat are as expected > + fallocate on the fd checks that offset/length on > fallocate(FALLOC_FL_PUNCH_HOLE) should be page aligned > > <snip> > + > +static void test_fallocate(int fd, size_t page_size, size_t total_size) > +{ > + int ret; > + > + ret = fallocate(fd, FALLOC_FL_KEEP_SIZE, 0, total_size); > + TEST_ASSERT(!ret, "fallocate with aligned offset and size should succeed"); > + > + ret = fallocate(fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE, > + page_size - 1, page_size); > + TEST_ASSERT(ret, "fallocate with unaligned offset should fail"); > + > + ret = fallocate(fd, FALLOC_FL_KEEP_SIZE, total_size, page_size); > + TEST_ASSERT(ret, "fallocate beginning at total_size should fail"); > + > + ret = fallocate(fd, FALLOC_FL_KEEP_SIZE, total_size + page_size, page_size); > + TEST_ASSERT(ret, "fallocate beginning at total_size should fail"); This should be TEST_ASSERT(ret, "fallocate beginning after total_size should fail"); > + > + ret = fallocate(fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE, > + total_size, page_size); > + TEST_ASSERT(!ret, "fallocate(PUNCH_HOLE) at total_size should succeed"); > + > + ret = fallocate(fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE, > + total_size + page_size, page_size); > + TEST_ASSERT(!ret, "fallocate(PUNCH_HOLE) after total_size should succeed"); > + > + ret = fallocate(fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE, > + page_size, page_size - 1); > + TEST_ASSERT(ret, "fallocate with unaligned size should fail"); > + > + ret = fallocate(fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE, > + page_size, page_size); > + TEST_ASSERT(!ret, "fallocate(PUNCH_HOLE) with aligned offset and size should succeed"); > + > + ret = fallocate(fd, FALLOC_FL_KEEP_SIZE, page_size, page_size); > + TEST_ASSERT(!ret, "fallocate to restore punched hole should succeed"); > +} > <snip>