1 /*
2 * Copyright (c) 2015-2016 Dmitry V. Levin <ldv@altlinux.org>
3 * Copyright (c) 2016 Red Hat, Inc.
4 * Copyright (c) 2016-2017 The strace developers.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. The name of the author may not be used to endorse or promote products
16 * derived from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30 #include "tests.h"
31 #include <asm/unistd.h>
32
33 #if defined __NR_userfaultfd && defined HAVE_LINUX_USERFAULTFD_H
34
35 # include <fcntl.h>
36 # include <inttypes.h>
37 # include <stdint.h>
38 # include <stdio.h>
39 # include <string.h>
40 # include <unistd.h>
41
42 # include <sys/ioctl.h>
43 # include <sys/mman.h>
44 # include <linux/ioctl.h>
45 # include <linux/userfaultfd.h>
46
47 int
main(void)48 main(void)
49 {
50 int rc;
51 int fd = syscall(__NR_userfaultfd, O_NONBLOCK);
52 size_t pagesize = getpagesize();
53
54 if (fd < 0)
55 perror_msg_and_skip("userfaultfd");
56
57 /* ---- API ---- */
58 TAIL_ALLOC_OBJECT_CONST_PTR(struct uffdio_api, api_struct);
59
60 /* With a bad fd */
61 memset(api_struct, 0, sizeof(*api_struct));
62 rc = ioctl(-1, UFFDIO_API, api_struct);
63 printf("ioctl(-1, UFFDIO_API, {api=0, features=0}) = %d %s (%m)\n",
64 rc, errno2name());
65 /* With a bad pointer */
66 rc = ioctl(fd, UFFDIO_API, NULL);
67 printf("ioctl(%d, UFFDIO_API, NULL) = %d %s (%m)\n",
68 fd, rc, errno2name());
69 /* Normal call */
70 api_struct->api = UFFD_API;
71 api_struct->features = 0;
72 rc = ioctl(fd, UFFDIO_API, api_struct);
73 printf("ioctl(%d, UFFDIO_API, {api=0xaa, features=0, "
74 "features.out=%#" PRIx64 ", ioctls=1<<_UFFDIO_REGISTER|"
75 "1<<_UFFDIO_UNREGISTER|1<<_UFFDIO_API",
76 fd, (uint64_t)api_struct->features);
77 api_struct->ioctls &= ~(1ull<<_UFFDIO_REGISTER|
78 1ull<<_UFFDIO_UNREGISTER|
79 1ull<<_UFFDIO_API);
80 if (api_struct->ioctls)
81 printf("|%#" PRIx64, (uint64_t)api_struct->ioctls);
82 printf("}) = %d\n", rc);
83
84 /* For the rest of the tests we need some anonymous memory */
85 void *area1 = mmap(NULL, pagesize, PROT_READ|PROT_WRITE,
86 MAP_PRIVATE|MAP_ANONYMOUS,
87 -1, 0);
88 if (area1 == MAP_FAILED)
89 perror_msg_and_fail("mmap area1");
90 void *area2 = mmap(NULL, pagesize, PROT_READ|PROT_WRITE,
91 MAP_PRIVATE|MAP_ANONYMOUS,
92 -1, 0);
93 if (area2 == MAP_FAILED)
94 perror_msg_and_fail("mmap area2");
95 madvise(area2, pagesize, MADV_DONTNEED);
96 *(char *)area1 = 42;
97
98 /* ---- REGISTER ---- */
99 struct uffdio_register *register_struct =
100 tail_alloc(sizeof(*register_struct));
101 memset(register_struct, 0, sizeof(*register_struct));
102
103 rc = ioctl(-1, UFFDIO_REGISTER, register_struct);
104 printf("ioctl(-1, UFFDIO_REGISTER, {range={start=0, len=0}, "
105 "mode=0}) = %d %s (%m)\n", rc, errno2name());
106
107 rc = ioctl(fd, UFFDIO_REGISTER, NULL);
108 printf("ioctl(%d, UFFDIO_REGISTER, NULL) = %d %s (%m)\n",
109 fd, rc, errno2name());
110
111 register_struct->range.start = (uint64_t)(uintptr_t)area2;
112 register_struct->range.len = pagesize;
113 register_struct->mode = UFFDIO_REGISTER_MODE_MISSING;
114 rc = ioctl(fd, UFFDIO_REGISTER, register_struct);
115 printf("ioctl(%d, UFFDIO_REGISTER, {range={start=%p, len=%#zx}, "
116 "mode=UFFDIO_REGISTER_MODE_MISSING, ioctls="
117 "1<<_UFFDIO_WAKE|1<<_UFFDIO_COPY|1<<_UFFDIO_ZEROPAGE",
118 fd, area2, pagesize);
119 register_struct->ioctls &= ~(1ull<<_UFFDIO_WAKE|
120 1ull<<_UFFDIO_COPY|
121 1ull<<_UFFDIO_ZEROPAGE);
122 if (register_struct->ioctls)
123 printf("|%#" PRIx64, (uint64_t)register_struct->ioctls);
124 printf("}) = %d\n", rc);
125
126 /* With area2 registered we can now do the atomic copies onto it
127 * but be careful not to access it in any other way otherwise
128 * userfaultfd will cause us to stall.
129 */
130 /* ---- COPY ---- */
131 TAIL_ALLOC_OBJECT_CONST_PTR(struct uffdio_copy, copy_struct);
132
133 memset(copy_struct, 0, sizeof(*copy_struct));
134 rc = ioctl(-1, UFFDIO_COPY, copy_struct);
135 printf("ioctl(-1, UFFDIO_COPY, {dst=0, src=0, len=0, mode=0"
136 "}) = %d %s (%m)\n", rc, errno2name());
137
138 rc = ioctl(fd, UFFDIO_COPY, NULL);
139 printf("ioctl(%d, UFFDIO_COPY, NULL) = %d %s (%m)\n",
140 fd, rc, errno2name());
141
142 copy_struct->dst = (uint64_t)(uintptr_t)area2;
143 copy_struct->src = (uint64_t)(uintptr_t)area1;
144 copy_struct->len = pagesize;
145 copy_struct->mode = UFFDIO_COPY_MODE_DONTWAKE;
146 rc = ioctl(fd, UFFDIO_COPY, copy_struct);
147 printf("ioctl(%d, UFFDIO_COPY, {dst=%p, src=%p, len=%#zx,"
148 " mode=UFFDIO_COPY_MODE_DONTWAKE, copy=%#zx}) = %d\n",
149 fd, area2, area1, pagesize, pagesize, rc);
150
151 /* ---- ZEROPAGE ---- */
152 TAIL_ALLOC_OBJECT_CONST_PTR(struct uffdio_zeropage, zero_struct);
153 madvise(area2, pagesize, MADV_DONTNEED);
154
155 memset(zero_struct, 0, sizeof(*zero_struct));
156 rc = ioctl(-1, UFFDIO_ZEROPAGE, zero_struct);
157 printf("ioctl(-1, UFFDIO_ZEROPAGE, {range={start=0, len=0}, mode=0"
158 "}) = %d %s (%m)\n", rc, errno2name());
159
160 rc = ioctl(fd, UFFDIO_ZEROPAGE, NULL);
161 printf("ioctl(%d, UFFDIO_ZEROPAGE, NULL) = %d %s (%m)\n",
162 fd, rc, errno2name());
163
164 zero_struct->range.start = (uint64_t)(uintptr_t)area2;
165 zero_struct->range.len = pagesize;
166 zero_struct->mode = UFFDIO_ZEROPAGE_MODE_DONTWAKE;
167 rc = ioctl(fd, UFFDIO_ZEROPAGE, zero_struct);
168 printf("ioctl(%d, UFFDIO_ZEROPAGE, {range={start=%p, len=%#zx},"
169 " mode=UFFDIO_ZEROPAGE_MODE_DONTWAKE, zeropage=%#zx}) = %d\n",
170 fd, area2, pagesize, pagesize, rc);
171
172 /* ---- WAKE ---- */
173 TAIL_ALLOC_OBJECT_CONST_PTR(struct uffdio_range, range_struct);
174 memset(range_struct, 0, sizeof(*range_struct));
175
176 rc = ioctl(-1, UFFDIO_WAKE, range_struct);
177 printf("ioctl(-1, UFFDIO_WAKE, {start=0, len=0}) = %d %s (%m)\n",
178 rc, errno2name());
179
180 rc = ioctl(fd, UFFDIO_WAKE, NULL);
181 printf("ioctl(%d, UFFDIO_WAKE, NULL) = %d %s (%m)\n",
182 fd, rc, errno2name());
183
184 range_struct->start = (uint64_t)(uintptr_t)area2;
185 range_struct->len = pagesize;
186 rc = ioctl(fd, UFFDIO_WAKE, range_struct);
187 printf("ioctl(%d, UFFDIO_WAKE, {start=%p, len=%#zx}) = %d\n",
188 fd, area2, pagesize, rc);
189
190 /* ---- UNREGISTER ---- */
191 memset(range_struct, 0, sizeof(*range_struct));
192
193 rc = ioctl(-1, UFFDIO_UNREGISTER, range_struct);
194 printf("ioctl(-1, UFFDIO_UNREGISTER, {start=0, len=0}) = %d %s (%m)\n",
195 rc, errno2name());
196
197 rc = ioctl(fd, UFFDIO_UNREGISTER, NULL);
198 printf("ioctl(%d, UFFDIO_UNREGISTER, NULL) = %d %s (%m)\n",
199 fd, rc, errno2name());
200
201 range_struct->start = (uint64_t)(uintptr_t)area2;
202 range_struct->len = pagesize;
203 rc = ioctl(fd, UFFDIO_UNREGISTER, range_struct);
204 printf("ioctl(%d, UFFDIO_UNREGISTER, {start=%p, len=%#zx}) = %d\n",
205 fd, area2, pagesize, rc);
206 puts("+++ exited with 0 +++");
207 return 0;
208 }
209
210 #else
211
212 SKIP_MAIN_UNDEFINED("__NR_userfaultfd && HAVE_LINUX_USERFAULTFD_H")
213
214 #endif
215