Linux: Add tables with system call numbers

The new tables are currently only used for consistency checks
with the installed kernel headers and the architecture-independent
system call names table.  They are based on Linux 5.4.

The goal is to use these architecture-specific tables to ensure
that system call wrappers are available irrespective of the version
of the installed kernel headers.

The tables are formatted in the form of C header files so that they
can be used directly in an #include directive, without external
preprocessing.  (External preprocessing of a plain table file
would introduce cross-subdirectory dependency issues.)  However,
the intent is that they can still be treated as tables and can be
processed by simple tools.

The irregular system call names on 32-bit arm add a complication.
The <fixup-asm-unistd.h> header is introduced to work around that,
and the system calls are listed under regular names in the
<arch-syscall.h> file.

A make target, update-syscalls-list, is added to patch the glibc
sources with data from the current kernel headers.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>

1 files changed, 24 insertions, 0 deletions

diff --git a/sysdeps/unix/sysv/linux/arm/fixup-asm-unistd.h b/sysdeps/unix/sysv/linux/arm/fixup-asm-unistd.h
new file mode 100644
index 0000000..541d6fc
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/arm/fixup-asm-unistd.h
@@ -0,0 +1,24 @@
+/* Regularize <asm/unistd.h> definitions.  Arm version.
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+/* These system calls have iregular names and are used by glibc.  */
+#ifndef __NR_cacheflush
+# define __NR_cacheflush __ARM_NR_cacheflush
+#endif
+#ifndef __NR_set_tls
+# define __NR_set_tls    __ARM_NR_set_tls
+#endif