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ARM: convert to generated system call tables

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Convert ARM to use a similar mechanism to x86 to generate the unistd.h
system call numbers and the various kernel system call tables.  This
means that rather than having to edit three places (asm/unistd.h for
the total number of system calls, uapi/asm/unistd.h for the system call
numbers, and arch/arm/kernel/calls.S for the call table) we have only
one place to edit, making the process much more simple.

The scripts have knowledge of the table padding requirements, so there's
no need to worry about __NR_syscalls not fitting within the immediate
constant field of ALU instructions anymore.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
This commit is contained in:
Russell King
2016-10-18 19:57:01 +01:00
parent 4e2648db9c
commit 96a8fae0fe
12 changed files with 625 additions and 873 deletions
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76
arch/arm/kernel/entry-common.S
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@@ -12,6 +12,11 @@
#include <asm/unistd.h>
#include <asm/ftrace.h>
#include <asm/unwind.h>
#ifdef CONFIG_AEABI
#include <asm/unistd-oabi.h>
#endif
.equ NR_syscalls, __NR_syscalls
#ifdef CONFIG_NEED_RET_TO_USER
#include <mach/entry-macro.S>
@@ -120,21 +125,6 @@ ENTRY(ret_from_fork)
b ret_slow_syscall
ENDPROC(ret_from_fork)
.equ NR_syscalls,0
#define CALL(x) .equ NR_syscalls,NR_syscalls+1
#include "calls.S"
/*
* Ensure that the system call table is equal to __NR_syscalls,
* which is the value the rest of the system sees
*/
.ifne NR_syscalls - __NR_syscalls
.error "__NR_syscalls is not equal to the size of the syscall table"
.endif
#undef CALL
#define CALL(x) .long x
/*=============================================================================
* SWI handler
*-----------------------------------------------------------------------------
@@ -291,22 +281,48 @@ __cr_alignment:
#endif
.ltorg
.macro syscall_table_start, sym
.equ __sys_nr, 0
.type \sym, #object
ENTRY(\sym)
.endm
.macro syscall, nr, func
.ifgt __sys_nr - \nr
.error "Duplicated/unorded system call entry"
.endif
.rept \nr - __sys_nr
.long sys_ni_syscall
.endr
.long \func
.equ __sys_nr, \nr + 1
.endm
.macro syscall_table_end, sym
.ifgt __sys_nr - __NR_syscalls
.error "System call table too big"
.endif
.rept __NR_syscalls - __sys_nr
.long sys_ni_syscall
.endr
.size \sym, . - \sym
.endm
#define NATIVE(nr, func) syscall nr, func
/*
* This is the syscall table declaration for native ABI syscalls.
* With EABI a couple syscalls are obsolete and defined as sys_ni_syscall.
*/
#define ABI(native, compat) native
syscall_table_start sys_call_table
#define COMPAT(nr, native, compat) syscall nr, native
#ifdef CONFIG_AEABI
#define OBSOLETE(syscall) sys_ni_syscall
#include <calls-eabi.S>
#else
#define OBSOLETE(syscall) syscall
#include <calls-oabi.S>
#endif
.type sys_call_table, #object
ENTRY(sys_call_table)
#include "calls.S"
#undef ABI
#undef OBSOLETE
#undef COMPAT
syscall_table_end sys_call_table
/*============================================================================
* Special system call wrappers
@@ -407,14 +423,10 @@ ENDPROC(sys_oabi_readahead)
* Let's declare a second syscall table for old ABI binaries
* using the compatibility syscall entries.
*/
#define ABI(native, compat) compat
#define OBSOLETE(syscall) syscall
.type sys_oabi_call_table, #object
ENTRY(sys_oabi_call_table)
#include "calls.S"
#undef ABI
#undef OBSOLETE
syscall_table_start sys_oabi_call_table
#define COMPAT(nr, native, compat) syscall nr, compat
#include <calls-oabi.S>
syscall_table_end sys_oabi_call_table
#endif