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-rw-r--r--sysdeps/unix/sysv/linux/rseq-internal.h73
1 files changed, 73 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/rseq-internal.h b/sysdeps/unix/sysv/linux/rseq-internal.h
new file mode 100644
index 0000000000..8f6772ca1d
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/rseq-internal.h
@@ -0,0 +1,73 @@
+/* Restartable Sequences internal API.  Linux implementation.
+   Copyright (C) 2020 Free Software Foundation, Inc.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef RSEQ_INTERNAL_H
+#define RSEQ_INTERNAL_H
+
+#include <sysdep.h>
+#include <errno.h>
+#include <kernel-features.h>
+#include <stdio.h>
+#include <sys/rseq.h>
+
+#ifdef RSEQ_SIG
+static inline void
+rseq_register_current_thread (void)
+{
+  int ret;
+
+  if (__rseq_abi.cpu_id != RSEQ_CPU_ID_UNINITIALIZED)
+    __libc_fatal ("glibc fatal error: "
+                  "rseq already initialized for this thread\n");
+  ret = INTERNAL_SYSCALL_CALL (rseq, &__rseq_abi, sizeof (struct rseq),
+                               0, RSEQ_SIG);
+  if (INTERNAL_SYSCALL_ERROR_P (ret))
+    {
+      const char *msg = NULL;
+
+      switch (INTERNAL_SYSCALL_ERRNO (ret))
+        {
+        case ENOSYS:    /* rseq system call not implemented.  */
+        case EPERM:     /* rseq system call filtered by seccomp.  */
+        case EACCES:    /* rseq system call filtered by seccomp.  */
+          __rseq_abi.cpu_id = RSEQ_CPU_ID_REGISTRATION_FAILED;
+          break;
+        case EBUSY:
+          msg = "glibc fatal error: rseq already registered for this thread\n";
+          break;
+        case EFAULT:
+          msg = "glibc fatal error: rseq parameter is an invalid address\n";
+          break;
+        case EINVAL:
+          msg = "glibc fatal error: rseq parameters are invalid\n";
+          break;
+        default:
+          msg = "glibc fatal error: unexpected rseq errno\n";
+          break;
+        }
+      if (msg != NULL)
+        __libc_fatal (msg);
+    }
+}
+#else /* RSEQ_SIG */
+static inline void
+rseq_register_current_thread (void)
+{
+}
+#endif /* RSEQ_SIG */
+
+#endif /* rseq-internal.h */