tools/testing/selftests/user_events/user_events_selftests.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2
   3 #ifndef _USER_EVENTS_SELFTESTS_H
   4 #define _USER_EVENTS_SELFTESTS_H
   5
   6 #include <sys/stat.h>
   7 #include <sys/types.h>
   8 #include <sys/mount.h>
   9 #include <unistd.h>
  10 #include <errno.h>
  11
  12 #include "../kselftest.h"
  13
  14 static inline void tracefs_unmount(void)
  15 {
  16         umount("/sys/kernel/tracing");
  17 }
  18
  19 static inline bool tracefs_enabled(char **message, bool *fail, bool *umount)
  20 {
  21         struct stat buf;
  22         int ret;
  23
  24         *message = "";
  25         *fail = false;
  26         *umount = false;
  27
  28         /* Ensure tracefs is installed */
  29         ret = stat("/sys/kernel/tracing", &buf);
  30
  31         if (ret == -1) {
  32                 *message = "Tracefs is not installed";
  33                 return false;
  34         }
  35
  36         /* Ensure mounted tracefs */
  37         ret = stat("/sys/kernel/tracing/README", &buf);
  38
  39         if (ret == -1 && errno == ENOENT) {
  40                 if (mount(NULL, "/sys/kernel/tracing", "tracefs", 0, NULL) != 0) {
  41                         *message = "Cannot mount tracefs";
  42                         *fail = true;
  43                         return false;
  44                 }
  45
  46                 *umount = true;
  47
  48                 ret = stat("/sys/kernel/tracing/README", &buf);
  49         }
  50
  51         if (ret == -1) {
  52                 *message = "Cannot access tracefs";
  53                 *fail = true;
  54                 return false;
  55         }
  56
  57         return true;
  58 }
  59
  60 static inline bool user_events_enabled(char **message, bool *fail, bool *umount)
  61 {
  62         struct stat buf;
  63         int ret;
  64
  65         *message = "";
  66         *fail = false;
  67         *umount = false;
  68
  69         if (getuid() != 0) {
  70                 *message = "Must be run as root";
  71                 *fail = true;
  72                 return false;
  73         }
  74
  75         if (!tracefs_enabled(message, fail, umount))
  76                 return false;
  77
  78         /* Ensure user_events is installed */
  79         ret = stat("/sys/kernel/tracing/user_events_data", &buf);
  80
  81         if (ret == -1) {
  82                 switch (errno) {
  83                 case ENOENT:
  84                         *message = "user_events is not installed";
  85                         return false;
  86
  87                 default:
  88                         *message = "Cannot access user_events_data";
  89                         *fail = true;
  90                         return false;
  91                 }
  92         }
  93
  94         return true;
  95 }
  96
  97 #define USER_EVENT_FIXTURE_SETUP(statement, umount) do { \
  98         char *message; \
  99         bool fail; \
 100         if (!user_events_enabled(&message, &fail, &(umount))) { \
 101                 if (fail) { \
 102                         TH_LOG("Setup failed due to: %s", message); \
 103                         ASSERT_FALSE(fail); \
 104                 } \
 105                 SKIP(statement, "Skipping due to: %s", message); \
 106         } \
 107 } while (0)
 108
 109 #define USER_EVENT_FIXTURE_TEARDOWN(umount) do { \
 110         if ((umount))  \
 111                 tracefs_unmount(); \
 112 } while (0)
 113
 114 #endif /* _USER_EVENTS_SELFTESTS_H */