#ifndef _LTTNG_PROBE_USER_H
#define _LTTNG_PROBE_USER_H
+#include <wrapper/uaccess.h>
+
/*
* Calculate string length. Include final null terminating character if there is
* one, or ends at first fault.
*/
long lttng_strlen_user_inatomic(const char *addr);
+/*
+ * We use __copy_from_user_inatomic to copy userspace data after
+ * checking with access_ok() and disabling page faults.
+ *
+ * Return 0 if OK, nonzero on error.
+ */
+static inline
+unsigned long lttng_copy_from_user_check_nofault(void *dest,
+ const void __user *src,
+ unsigned long len)
+{
+ unsigned long ret;
+
+ if (!lttng_access_ok(VERIFY_READ, src, len))
+ return 1;
+ pagefault_disable();
+ ret = __copy_from_user_inatomic(dest, src, len);
+ pagefault_enable();
+ return ret;
+}
+
#endif /* _LTTNG_PROBE_USER_H */