selftests/vm/mlock2.h

0001 /* SPDX-License-Identifier: GPL-2.0 */
0002 #include <syscall.h>
0003 #include <errno.h>
0004 #include <stdio.h>
0005 #include <stdlib.h>
0006
0007 #ifndef MLOCK_ONFAULT
0008 #define MLOCK_ONFAULT 1
0009 #endif
0010
0011 #ifndef MCL_ONFAULT
0012 #define MCL_ONFAULT (MCL_FUTURE << 1)
0013 #endif
0014
0015 static int mlock2_(void *start, size_t len, int flags)
0016 {
0017 #ifdef __NR_mlock2
0018     return syscall(__NR_mlock2, start, len, flags);
0019 #else
0020     errno = ENOSYS;
0021     return -1;
0022 #endif
0023 }
0024
0025 static FILE *seek_to_smaps_entry(unsigned long addr)
0026 {
0027     FILE *file;
0028     char *line = NULL;
0029     size_t size = 0;
0030     unsigned long start, end;
0031     char perms[5];
0032     unsigned long offset;
0033     char dev[32];
0034     unsigned long inode;
0035     char path[BUFSIZ];
0036
0037     file = fopen("/proc/self/smaps", "r");
0038     if (!file) {
0039         perror("fopen smaps");
0040         _exit(1);
0041     }
0042
0043     while (getline(&line, &size, file) > 0) {
0044         if (sscanf(line, "%lx-%lx %s %lx %s %lu %s\n",
0045                &start, &end, perms, &offset, dev, &inode, path) < 6)
0046             goto next;
0047
0048         if (start <= addr && addr < end)
0049             goto out;
0050
0051 next:
0052         free(line);
0053         line = NULL;
0054         size = 0;
0055     }
0056
0057     fclose(file);
0058     file = NULL;
0059
0060 out:
0061     free(line);
0062     return file;
0063 }