[PATCH 1/2] scripts: add generic syscalltbl.sh

From: Masahiro Yamada
Date: Mon Feb 15 2021 - 21:05:29 EST


Most of architectures generate syscall headers at the compile time
in a similar way.

The syscall table has the same format for all architectures. Each line
has up to 5 fields; syscall number, ABI, syscall name, native entry
point, and compat entry point. The syscall table is processed by
syscalltbl.sh script into header files.

Despite the same pattern, scripts are maintained per architecture,
which results in code duplication and bad maintainability.

As of v5.11-rc1, 12 architectures duplicate similar shell scripts:

$ find arch -name syscalltbl.sh | sort
arch/alpha/kernel/syscalls/syscalltbl.sh
arch/arm/tools/syscalltbl.sh
arch/ia64/kernel/syscalls/syscalltbl.sh
arch/m68k/kernel/syscalls/syscalltbl.sh
arch/microblaze/kernel/syscalls/syscalltbl.sh
arch/mips/kernel/syscalls/syscalltbl.sh
arch/parisc/kernel/syscalls/syscalltbl.sh
arch/powerpc/kernel/syscalls/syscalltbl.sh
arch/sh/kernel/syscalls/syscalltbl.sh
arch/sparc/kernel/syscalls/syscalltbl.sh
arch/x86/entry/syscalls/syscalltbl.sh
arch/xtensa/kernel/syscalls/syscalltbl.sh

My goal is to unify them into scripts/syscalltbl.sh.

__SYSCALL_WITH_COMPAT should be defined as follows:

32-bit kernel:
#define __SYSCALL_WITH_COMPAT(nr, native, compat) __SYSCALL(nr, native)

64-bit kernel:

#define __SYSCALL_WITH_COMPAT(nr, native, compat) __SYSCALL(nr, compat)

Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
---

scripts/syscalltbl.sh | 73 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 73 insertions(+)
create mode 100755 scripts/syscalltbl.sh

diff --git a/scripts/syscalltbl.sh b/scripts/syscalltbl.sh
new file mode 100755
index 000000000000..aa6ab156301c
--- /dev/null
+++ b/scripts/syscalltbl.sh
@@ -0,0 +1,73 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Generate a syscall table header.
+#
+# Each line of the syscall table should have the following format:
+#
+# NR ABI NAME [NATIVE] [COMPAT]
+#
+# NR syscall number
+# ABI ABI name
+# NAME syscall name
+# NATIVE native entry point (optional)
+# COMPAT compat entry point (optional)
+
+set -e
+
+usage() {
+ echo >&2 "usage: $0 [--abis ABIS] INFILE OUTFILE" >&2
+ echo >&2
+ echo >&2 " INFILE input syscall table"
+ echo >&2 " OUTFILE output header file"
+ echo >&2
+ echo >&2 "options:"
+ echo >&2 " --abis ABIS ABI(s) to handle (By default, all lines are handled)"
+ exit 1
+}
+
+# default unless specified by options
+abis=
+
+while [ $# -gt 0 ]
+do
+ case $1 in
+ --abis)
+ abis=$(echo "($2)" | tr ',' '|')
+ shift 2;;
+ -*)
+ echo "$1: unknown option" >&2
+ usage;;
+ *)
+ break;;
+ esac
+done
+
+if [ $# -ne 2 ]; then
+ usage
+fi
+
+infile="$1"
+outfile="$2"
+
+nxt=0
+
+grep -E "^[0-9]+[[:space:]]+$abis" "$infile" | sort -n | {
+
+ while read nr abi name native compat ; do
+
+ while [ $nxt -lt $nr ]; do
+ echo "__SYSCALL($nxt, sys_ni_syscall)"
+ nxt=$((nxt + 1))
+ done
+
+ if [ -n "$compat" ]; then
+ echo "__SYSCALL_WITH_COMPAT($nr, $native, $compat)"
+ elif [ -n "$native" ]; then
+ echo "__SYSCALL($nr, $native)"
+ else
+ echo "__SYSCALL($nr, sys_ni_syscall)"
+ fi
+ nxt=$((nr + 1))
+ done
+} > "$outfile"
--
2.27.0