tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright Intel Corporation, 2023
4 *
5 * Author: Chao Peng <chao.p.peng@linux.intel.com>
6 */
7#include <stdlib.h>
8#include <string.h>
9#include <unistd.h>
10#include <errno.h>
11#include <stdio.h>
12#include <fcntl.h>
13
14#include <linux/bitmap.h>
15#include <linux/falloc.h>
16#include <sys/mman.h>
17#include <sys/types.h>
18#include <sys/stat.h>
19
20#include "kvm_util.h"
21#include "test_util.h"
22
23static void test_file_read_write(int fd)
24{
25 char buf[64];
26
27 TEST_ASSERT(read(fd, buf, sizeof(buf)) < 0,
28 "read on a guest_mem fd should fail");
29 TEST_ASSERT(write(fd, buf, sizeof(buf)) < 0,
30 "write on a guest_mem fd should fail");
31 TEST_ASSERT(pread(fd, buf, sizeof(buf), 0) < 0,
32 "pread on a guest_mem fd should fail");
33 TEST_ASSERT(pwrite(fd, buf, sizeof(buf), 0) < 0,
34 "pwrite on a guest_mem fd should fail");
35}
36
37static void test_mmap(int fd, size_t page_size)
38{
39 char *mem;
40
41 mem = mmap(NULL, page_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
42 TEST_ASSERT_EQ(mem, MAP_FAILED);
43}
44
45static void test_file_size(int fd, size_t page_size, size_t total_size)
46{
47 struct stat sb;
48 int ret;
49
50 ret = fstat(fd, &sb);
51 TEST_ASSERT(!ret, "fstat should succeed");
52 TEST_ASSERT_EQ(sb.st_size, total_size);
53 TEST_ASSERT_EQ(sb.st_blksize, page_size);
54}
55
56static void test_fallocate(int fd, size_t page_size, size_t total_size)
57{
58 int ret;
59
60 ret = fallocate(fd, FALLOC_FL_KEEP_SIZE, 0, total_size);
61 TEST_ASSERT(!ret, "fallocate with aligned offset and size should succeed");
62
63 ret = fallocate(fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE,
64 page_size - 1, page_size);
65 TEST_ASSERT(ret, "fallocate with unaligned offset should fail");
66
67 ret = fallocate(fd, FALLOC_FL_KEEP_SIZE, total_size, page_size);
68 TEST_ASSERT(ret, "fallocate beginning at total_size should fail");
69
70 ret = fallocate(fd, FALLOC_FL_KEEP_SIZE, total_size + page_size, page_size);
71 TEST_ASSERT(ret, "fallocate beginning after total_size should fail");
72
73 ret = fallocate(fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE,
74 total_size, page_size);
75 TEST_ASSERT(!ret, "fallocate(PUNCH_HOLE) at total_size should succeed");
76
77 ret = fallocate(fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE,
78 total_size + page_size, page_size);
79 TEST_ASSERT(!ret, "fallocate(PUNCH_HOLE) after total_size should succeed");
80
81 ret = fallocate(fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE,
82 page_size, page_size - 1);
83 TEST_ASSERT(ret, "fallocate with unaligned size should fail");
84
85 ret = fallocate(fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE,
86 page_size, page_size);
87 TEST_ASSERT(!ret, "fallocate(PUNCH_HOLE) with aligned offset and size should succeed");
88
89 ret = fallocate(fd, FALLOC_FL_KEEP_SIZE, page_size, page_size);
90 TEST_ASSERT(!ret, "fallocate to restore punched hole should succeed");
91}
92
93static void test_invalid_punch_hole(int fd, size_t page_size, size_t total_size)
94{
95 struct {
96 off_t offset;
97 off_t len;
98 } testcases[] = {
99 {0, 1},
100 {0, page_size - 1},
101 {0, page_size + 1},
102
103 {1, 1},
104 {1, page_size - 1},
105 {1, page_size},
106 {1, page_size + 1},
107
108 {page_size, 1},
109 {page_size, page_size - 1},
110 {page_size, page_size + 1},
111 };
112 int ret, i;
113
114 for (i = 0; i < ARRAY_SIZE(testcases); i++) {
115 ret = fallocate(fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE,
116 testcases[i].offset, testcases[i].len);
117 TEST_ASSERT(ret == -1 && errno == EINVAL,
118 "PUNCH_HOLE with !PAGE_SIZE offset (%lx) and/or length (%lx) should fail",
119 testcases[i].offset, testcases[i].len);
120 }
121}
122
123static void test_create_guest_memfd_invalid(struct kvm_vm *vm)
124{
125 size_t page_size = getpagesize();
126 uint64_t flag;
127 size_t size;
128 int fd;
129
130 for (size = 1; size < page_size; size++) {
131 fd = __vm_create_guest_memfd(vm, size, 0);
132 TEST_ASSERT(fd == -1 && errno == EINVAL,
133 "guest_memfd() with non-page-aligned page size '0x%lx' should fail with EINVAL",
134 size);
135 }
136
137 for (flag = BIT(0); flag; flag <<= 1) {
138 fd = __vm_create_guest_memfd(vm, page_size, flag);
139 TEST_ASSERT(fd == -1 && errno == EINVAL,
140 "guest_memfd() with flag '0x%lx' should fail with EINVAL",
141 flag);
142 }
143}
144
145static void test_create_guest_memfd_multiple(struct kvm_vm *vm)
146{
147 int fd1, fd2, ret;
148 struct stat st1, st2;
149
150 fd1 = __vm_create_guest_memfd(vm, 4096, 0);
151 TEST_ASSERT(fd1 != -1, "memfd creation should succeed");
152
153 ret = fstat(fd1, &st1);
154 TEST_ASSERT(ret != -1, "memfd fstat should succeed");
155 TEST_ASSERT(st1.st_size == 4096, "memfd st_size should match requested size");
156
157 fd2 = __vm_create_guest_memfd(vm, 8192, 0);
158 TEST_ASSERT(fd2 != -1, "memfd creation should succeed");
159
160 ret = fstat(fd2, &st2);
161 TEST_ASSERT(ret != -1, "memfd fstat should succeed");
162 TEST_ASSERT(st2.st_size == 8192, "second memfd st_size should match requested size");
163
164 ret = fstat(fd1, &st1);
165 TEST_ASSERT(ret != -1, "memfd fstat should succeed");
166 TEST_ASSERT(st1.st_size == 4096, "first memfd st_size should still match requested size");
167 TEST_ASSERT(st1.st_ino != st2.st_ino, "different memfd should have different inode numbers");
168
169 close(fd2);
170 close(fd1);
171}
172
173int main(int argc, char *argv[])
174{
175 size_t page_size;
176 size_t total_size;
177 int fd;
178 struct kvm_vm *vm;
179
180 TEST_REQUIRE(kvm_has_cap(KVM_CAP_GUEST_MEMFD));
181
182 page_size = getpagesize();
183 total_size = page_size * 4;
184
185 vm = vm_create_barebones();
186
187 test_create_guest_memfd_invalid(vm);
188 test_create_guest_memfd_multiple(vm);
189
190 fd = vm_create_guest_memfd(vm, total_size, 0);
191
192 test_file_read_write(fd);
193 test_mmap(fd, page_size);
194 test_file_size(fd, page_size, total_size);
195 test_fallocate(fd, page_size, total_size);
196 test_invalid_punch_hole(fd, page_size, total_size);
197
198 close(fd);
199}