From dd35afc22b76766e827c9e67ebc4b7bf6e31ecab Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Sat, 14 Jan 2006 16:36:12 +0000 Subject: [ARM] 3110/5: old ABI compat: multi-ABI syscall entry support Patch from Nicolas Pitre This patch adds the required code to support both user space ABIs at the same time. A second syscall table is created to include legacy ABI syscalls that need an ABI compat wrapper. Signed-off-by: Nicolas Pitre Signed-off-by: Russell King --- arch/arm/kernel/entry-common.S | 78 ++++++++++++++++++++++++++++++++++++++---- 1 file changed, 71 insertions(+), 7 deletions(-) (limited to 'arch/arm/kernel/entry-common.S') diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 59ce1bcec42..8826d9803ae 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -123,23 +123,49 @@ ENTRY(vector_swi) /* * Get the system call number. */ -#if defined(CONFIG_AEABI) - @ syscall number is in scno (r7) already. +#if defined(CONFIG_OABI_COMPAT) + /* + * If we have CONFIG_OABI_COMPAT then we need to look at the swi + * value to determine if it is an EABI or an old ABI call. + */ +#ifdef CONFIG_ARM_THUMB + tst r8, #PSR_T_BIT + movne r10, #0 @ no thumb OABI emulation + ldreq r10, [lr, #-4] @ get SWI instruction +#else + ldr r10, [lr, #-4] @ get SWI instruction + A710( and ip, r10, #0x0f000000 @ check for SWI ) + A710( teq ip, #0x0f000000 ) + A710( bne .Larm710bug ) +#endif + +#elif defined(CONFIG_AEABI) + + /* + * Pure EABI user space always put syscall number into scno (r7). + */ A710( ldr ip, [lr, #-4] @ get SWI instruction ) A710( and ip, ip, #0x0f000000 @ check for SWI ) A710( teq ip, #0x0f000000 ) A710( bne .Larm710bug ) + #elif defined(CONFIG_ARM_THUMB) + + /* Legacy ABI only, possibly thumb mode. */ tst r8, #PSR_T_BIT @ this is SPSR from save_user_regs addne scno, r7, #__NR_SYSCALL_BASE @ put OS number in ldreq scno, [lr, #-4] + #else + + /* Legacy ABI only. */ ldr scno, [lr, #-4] @ get SWI instruction A710( and ip, scno, #0x0f000000 @ check for SWI ) A710( teq ip, #0x0f000000 ) A710( bne .Larm710bug ) + #endif #ifdef CONFIG_ALIGNMENT_TRAP @@ -150,12 +176,24 @@ ENTRY(vector_swi) enable_irq get_thread_info tsk + adr tbl, sys_call_table @ load syscall table pointer ldr ip, [tsk, #TI_FLAGS] @ check for syscall tracing -#ifndef CONFIG_AEABI + +#if defined(CONFIG_OABI_COMPAT) + /* + * If the swi argument is zero, this is an EABI call and we do nothing. + * + * If this is an old ABI call, get the syscall number into scno and + * get the old ABI syscall table address. + */ + bics r10, r10, #0xff000000 + eorne scno, r10, #__NR_OABI_SYSCALL_BASE + ldrne tbl, =sys_oabi_call_table +#elif !defined(CONFIG_AEABI) bic scno, scno, #0xff000000 @ mask off SWI op-code eor scno, scno, #__NR_SYSCALL_BASE @ check OS number #endif - adr tbl, sys_call_table @ load syscall table pointer + stmdb sp!, {r4, r5} @ push fifth and sixth args tst ip, #_TIF_SYSCALL_TRACE @ are we tracing syscalls? bne __sys_trace @@ -199,11 +237,25 @@ __sys_trace_return: .type __cr_alignment, #object __cr_alignment: .word cr_alignment +#endif + .ltorg + +/* + * 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 +#ifdef CONFIG_AEABI +#define OBSOLETE(syscall) sys_ni_syscall +#else +#define OBSOLETE(syscall) syscall #endif .type sys_call_table, #object ENTRY(sys_call_table) #include "calls.S" +#undef ABI +#undef OBSOLETE /*============================================================================ * Special system call wrappers @@ -212,8 +264,7 @@ ENTRY(sys_call_table) @ r8 = syscall table .type sys_syscall, #function sys_syscall: -#ifndef CONFIG_AEABI - eor scno, r0, #__NR_SYSCALL_BASE + eor scno, r0, #__NR_OABI_SYSCALL_BASE cmp scno, #__NR_syscall - __NR_SYSCALL_BASE cmpne scno, #NR_syscalls @ check range stmloia sp, {r5, r6} @ shuffle args @@ -222,7 +273,6 @@ sys_syscall: movlo r2, r3 movlo r3, r4 ldrlo pc, [tbl, scno, lsl #2] -#endif b sys_ni_syscall sys_fork_wrapper: @@ -290,6 +340,7 @@ sys_mmap2: #endif #ifdef CONFIG_OABI_COMPAT + /* * These are syscalls with argument register differences */ @@ -318,5 +369,18 @@ sys_oabi_readahead: mov r2, r1 b sys_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 + #endif -- cgit v1.2.3-18-g5258