1 /*
2 * Copyright (c) 2015-2016 Dmitry V. Levin <ldv@altlinux.org>
3 * Copyright (c) 2016 Red Hat, Inc.
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include "tests.h"
30 #include <asm/unistd.h>
31
32 #if defined __NR_userfaultfd && defined HAVE_LINUX_USERFAULTFD_H
33
34 # include <fcntl.h>
35 # include <inttypes.h>
36 # include <stdint.h>
37 # include <stdio.h>
38 # include <string.h>
39 # include <unistd.h>
40
41 # include <sys/ioctl.h>
42 # include <sys/mman.h>
43 # include <linux/ioctl.h>
44 # include <linux/userfaultfd.h>
45
46 int
main(void)47 main(void)
48 {
49 int rc;
50 int fd = syscall(__NR_userfaultfd, O_NONBLOCK);
51 size_t pagesize = getpagesize();
52
53 if (fd < 0)
54 perror_msg_and_skip("userfaultfd");
55
56 /* ---- API ---- */
57 struct uffdio_api *api_struct = tail_alloc(sizeof(*api_struct));
58
59 /* With a bad fd */
60 memset(api_struct, 0, sizeof(*api_struct));
61 rc = ioctl(-1, UFFDIO_API, api_struct);
62 printf("ioctl(-1, UFFDIO_API, {api=0, features=0}) = %d %s (%m)\n",
63 rc, errno2name());
64 /* With a bad pointer */
65 rc = ioctl(fd, UFFDIO_API, NULL);
66 printf("ioctl(%d, UFFDIO_API, NULL) = %d %s (%m)\n",
67 fd, rc, errno2name());
68 /* Normal call */
69 api_struct->api = UFFD_API;
70 api_struct->features = 0;
71 rc = ioctl(fd, UFFDIO_API, api_struct);
72 printf("ioctl(%d, UFFDIO_API, {api=0xaa, features=0, "
73 "features.out=%#" PRIx64 ", " "ioctls=1<<_UFFDIO_REGISTER|"
74 "1<<_UFFDIO_UNREGISTER|1<<_UFFDIO_API",
75 fd, (uint64_t)api_struct->features);
76 api_struct->ioctls &= ~(1ull<<_UFFDIO_REGISTER|
77 1ull<<_UFFDIO_UNREGISTER|
78 1ull<<_UFFDIO_API);
79 if (api_struct->ioctls)
80 printf("|%#" PRIx64, (uint64_t)api_struct->ioctls);
81 printf("}) = %d\n", rc);
82
83 /* For the rest of the tests we need some anonymous memory */
84 void *area1 = mmap(NULL, pagesize, PROT_READ|PROT_WRITE,
85 MAP_PRIVATE|MAP_ANONYMOUS,
86 -1, 0);
87 if (area1 == MAP_FAILED)
88 perror_msg_and_fail("mmap area1");
89 void *area2 = mmap(NULL, pagesize, PROT_READ|PROT_WRITE,
90 MAP_PRIVATE|MAP_ANONYMOUS,
91 -1, 0);
92 if (area2 == MAP_FAILED)
93 perror_msg_and_fail("mmap area2");
94 madvise(area2, pagesize, MADV_DONTNEED);
95 *(char *)area1 = 42;
96
97 /* ---- REGISTER ---- */
98 struct uffdio_register *register_struct =
99 tail_alloc(sizeof(*register_struct));
100 memset(register_struct, 0, sizeof(*register_struct));
101
102 rc = ioctl(-1, UFFDIO_REGISTER, register_struct);
103 printf("ioctl(-1, UFFDIO_REGISTER, {range={start=0, len=0}, "
104 "mode=0}) = %d %s (%m)\n", rc, errno2name());
105
106 rc = ioctl(fd, UFFDIO_REGISTER, NULL);
107 printf("ioctl(%d, UFFDIO_REGISTER, NULL) = %d %s (%m)\n",
108 fd, rc, errno2name());
109
110 register_struct->range.start = (uint64_t)(uintptr_t)area2;
111 register_struct->range.len = pagesize;
112 register_struct->mode = UFFDIO_REGISTER_MODE_MISSING;
113 rc = ioctl(fd, UFFDIO_REGISTER, register_struct);
114 printf("ioctl(%d, UFFDIO_REGISTER, {range={start=%p, len=%#zx}, "
115 "mode=UFFDIO_REGISTER_MODE_MISSING, ioctls="
116 "1<<_UFFDIO_WAKE|1<<_UFFDIO_COPY|1<<_UFFDIO_ZEROPAGE",
117 fd, area2, pagesize);
118 register_struct->ioctls &= ~(1ull<<_UFFDIO_WAKE|
119 1ull<<_UFFDIO_COPY|
120 1ull<<_UFFDIO_ZEROPAGE);
121 if (register_struct->ioctls)
122 printf("|%#" PRIx64, (uint64_t)register_struct->ioctls);
123 printf("}) = %d\n", rc);
124
125 /* With area2 registered we can now do the atomic copies onto it
126 * but be careful not to access it in any other way otherwise
127 * userfaultfd will cause us to stall.
128 */
129 /* ---- COPY ---- */
130 struct uffdio_copy *copy_struct = tail_alloc(sizeof(*copy_struct));
131
132 memset(copy_struct, 0, sizeof(*copy_struct));
133 rc = ioctl(-1, UFFDIO_COPY, copy_struct);
134 printf("ioctl(-1, UFFDIO_COPY, {dst=0, src=0, len=0, mode=0"
135 "}) = %d %s (%m)\n", rc, errno2name());
136
137 rc = ioctl(fd, UFFDIO_COPY, NULL);
138 printf("ioctl(%d, UFFDIO_COPY, NULL) = %d %s (%m)\n",
139 fd, rc, errno2name());
140
141 copy_struct->dst = (uint64_t)(uintptr_t)area2;
142 copy_struct->src = (uint64_t)(uintptr_t)area1;
143 copy_struct->len = pagesize;
144 copy_struct->mode = UFFDIO_COPY_MODE_DONTWAKE;
145 rc = ioctl(fd, UFFDIO_COPY, copy_struct);
146 printf("ioctl(%d, UFFDIO_COPY, {dst=%p, src=%p, len=%#zx,"
147 " mode=UFFDIO_COPY_MODE_DONTWAKE, copy=%#zx}) = %d\n",
148 fd, area2, area1, pagesize, pagesize, rc);
149
150 /* ---- ZEROPAGE ---- */
151 struct uffdio_zeropage *zero_struct = tail_alloc(sizeof(*zero_struct));
152 madvise(area2, pagesize, MADV_DONTNEED);
153
154 memset(zero_struct, 0, sizeof(*zero_struct));
155 rc = ioctl(-1, UFFDIO_ZEROPAGE, zero_struct);
156 printf("ioctl(-1, UFFDIO_ZEROPAGE, {range={start=0, len=0}, mode=0"
157 "}) = %d %s (%m)\n", rc, errno2name());
158
159 rc = ioctl(fd, UFFDIO_ZEROPAGE, NULL);
160 printf("ioctl(%d, UFFDIO_ZEROPAGE, NULL) = %d %s (%m)\n",
161 fd, rc, errno2name());
162
163 zero_struct->range.start = (uint64_t)(uintptr_t)area2;
164 zero_struct->range.len = pagesize;
165 zero_struct->mode = UFFDIO_ZEROPAGE_MODE_DONTWAKE;
166 rc = ioctl(fd, UFFDIO_ZEROPAGE, zero_struct);
167 printf("ioctl(%d, UFFDIO_ZEROPAGE, {range={start=%p, len=%#zx},"
168 " mode=UFFDIO_ZEROPAGE_MODE_DONTWAKE, zeropage=%#zx}) = %d\n",
169 fd, area2, pagesize, pagesize, rc);
170
171 /* ---- WAKE ---- */
172 struct uffdio_range *range_struct = tail_alloc(sizeof(*range_struct));
173 memset(range_struct, 0, sizeof(*range_struct));
174
175 rc = ioctl(-1, UFFDIO_WAKE, range_struct);
176 printf("ioctl(-1, UFFDIO_WAKE, {start=0, len=0}) = %d %s (%m)\n",
177 rc, errno2name());
178
179 rc = ioctl(fd, UFFDIO_WAKE, NULL);
180 printf("ioctl(%d, UFFDIO_WAKE, NULL) = %d %s (%m)\n",
181 fd, rc, errno2name());
182
183 range_struct->start = (uint64_t)(uintptr_t)area2;
184 range_struct->len = pagesize;
185 rc = ioctl(fd, UFFDIO_WAKE, range_struct);
186 printf("ioctl(%d, UFFDIO_WAKE, {start=%p, len=%#zx}) = %d\n",
187 fd, area2, pagesize, rc);
188
189 /* ---- UNREGISTER ---- */
190 memset(range_struct, 0, sizeof(*range_struct));
191
192 rc = ioctl(-1, UFFDIO_UNREGISTER, range_struct);
193 printf("ioctl(-1, UFFDIO_UNREGISTER, {start=0, len=0}) = %d %s (%m)\n",
194 rc, errno2name());
195
196 rc = ioctl(fd, UFFDIO_UNREGISTER, NULL);
197 printf("ioctl(%d, UFFDIO_UNREGISTER, NULL) = %d %s (%m)\n",
198 fd, rc, errno2name());
199
200 range_struct->start = (uint64_t)(uintptr_t)area2;
201 range_struct->len = pagesize;
202 rc = ioctl(fd, UFFDIO_UNREGISTER, range_struct);
203 printf("ioctl(%d, UFFDIO_UNREGISTER, {start=%p, len=%#zx}) = %d\n",
204 fd, area2, pagesize, rc);
205 puts("+++ exited with 0 +++");
206 return 0;
207 }
208
209 #else
210
211 SKIP_MAIN_UNDEFINED("__NR_userfaultfd && HAVE_LINUX_USERFAULTFD_H")
212
213 #endif
214