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
 14static inline void tracefs_unmount(void)
 15{
 16	umount("/sys/kernel/tracing");
 17}
 18
 19static 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
 60static 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 */