usr/src/test/libc-tests/tests/random/inz_split_vpp.c

   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
  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 }