1 /*
2 * This file and its contents are supplied under the terms of the
3 * Common Development and Distribution License ("CDDL"), version 1.0.
4 * You may only use this file in accordance with the terms of version
5 * 1.0 of the CDDL.
6 *
7 * A full copy of the text of the CDDL should have accompanied this
8 * source. A copy of the CDDL is also available via the Internet at
9 * http://www.illumos.org/license/CDDL.
10 */
11
12 /*
13 * Copyright (c) 2015, Joyent, Inc.
14 */
15
16 /*
17 * Verify that using MC_INHERIT_ZERO works just fine when applied to a subset of
18 * a region, meaning that we should have created a struct vpage for that region.
19 * Then unmap a hole in the middle, so that way we force subsets of children
20 * that have struct vpage entries.
21 */
22
23 #include <sys/types.h>
24 #include <unistd.h>
25 #include <assert.h>
26 #include <sys/mman.h>
27 #include <string.h>
28 #include <errno.h>
29 #include <stdlib.h>
30 #include <wait.h>
31
32 int
main(void)33 main(void)
34 {
35 void *buf;
36 pid_t child;
37 int ret, i;
38 siginfo_t info;
39 uint8_t *ubuf;
40 size_t pgsz = sysconf(_SC_PAGESIZE);
41 size_t mapsz = 10 * pgsz;
42 size_t clrsz = 5 * pgsz;
43 size_t clroff = 2 * pgsz;
44 size_t spltsz = 1 * pgsz;
45 size_t spltoff = 3 * pgsz;
46
47 buf = mmap(NULL, mapsz, PROT_READ | PROT_WRITE,
48 MAP_PRIVATE | MAP_ANON, -1, 0);
49 assert(buf != MAP_FAILED);
50 memset(buf, 'a', mapsz);
51
52 ret = memcntl(buf + clroff, clrsz, MC_INHERIT_ZERO, 0, 0, 0);
53 assert(ret == 0);
54
55 ret = munmap(buf + spltoff, spltsz);
56 assert(ret == 0);
57
58 child = fork();
59 if (child == 0) {
60 ubuf = buf;
61 for (i = 0; i < clroff; i++)
62 assert(ubuf[i] == 'a');
63 for (i = clroff; i < spltoff; i++)
64 assert(ubuf[i] == 0);
65 for (i = spltoff + spltsz; i < clroff + clrsz; i++)
66 assert(ubuf[i] == 0);
67 for (i = clrsz + clroff; i < mapsz; i++)
68 assert(ubuf[i] == 'a');
69 exit(0);
70 }
71 assert(child != -1);
72
73 do {
74 ret = waitid(P_PID, child, &info, WEXITED);
75 } while (ret == -1 && errno == EINTR);
76 assert(ret == 0);
77 assert(info.si_pid == child);
78 assert(info.si_status == 0);
79
80 ubuf = buf;
81 for (i = 0; i < clroff; i++)
82 assert(ubuf[i] == 'a');
83 for (i = clroff; i < spltoff; i++)
84 assert(ubuf[i] == 'a');
85 for (i = spltoff + spltsz; i < clroff + clrsz; i++)
86 assert(ubuf[i] == 'a');
87 for (i = clrsz + clroff; i < mapsz; i++)
88 assert(ubuf[i] == 'a');
89
90
91 return (0);
92 }
93