284 lines
6.6 KiB
ArmAsm
284 lines
6.6 KiB
ArmAsm
/*
|
|
* linux/arch/arm/kernel/entry-common.S
|
|
*
|
|
* Copyright (C) 2000 Russell King
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
#include <linux/config.h>
|
|
|
|
#include <asm/unistd.h>
|
|
|
|
#include "entry-header.S"
|
|
|
|
|
|
.align 5
|
|
/*
|
|
* This is the fast syscall return path. We do as little as
|
|
* possible here, and this includes saving r0 back into the SVC
|
|
* stack.
|
|
*/
|
|
ret_fast_syscall:
|
|
disable_irq @ disable interrupts
|
|
ldr r1, [tsk, #TI_FLAGS]
|
|
tst r1, #_TIF_WORK_MASK
|
|
bne fast_work_pending
|
|
|
|
@ fast_restore_user_regs
|
|
ldr r1, [sp, #S_OFF + S_PSR] @ get calling cpsr
|
|
ldr lr, [sp, #S_OFF + S_PC]! @ get pc
|
|
msr spsr_cxsf, r1 @ save in spsr_svc
|
|
ldmdb sp, {r1 - lr}^ @ get calling r1 - lr
|
|
mov r0, r0
|
|
add sp, sp, #S_FRAME_SIZE - S_PC
|
|
movs pc, lr @ return & move spsr_svc into cpsr
|
|
|
|
/*
|
|
* Ok, we need to do extra processing, enter the slow path.
|
|
*/
|
|
fast_work_pending:
|
|
str r0, [sp, #S_R0+S_OFF]! @ returned r0
|
|
work_pending:
|
|
tst r1, #_TIF_NEED_RESCHED
|
|
bne work_resched
|
|
tst r1, #_TIF_NOTIFY_RESUME | _TIF_SIGPENDING
|
|
beq no_work_pending
|
|
mov r0, sp @ 'regs'
|
|
mov r2, why @ 'syscall'
|
|
bl do_notify_resume
|
|
disable_irq @ disable interrupts
|
|
b no_work_pending
|
|
|
|
work_resched:
|
|
bl schedule
|
|
/*
|
|
* "slow" syscall return path. "why" tells us if this was a real syscall.
|
|
*/
|
|
ENTRY(ret_to_user)
|
|
ret_slow_syscall:
|
|
disable_irq @ disable interrupts
|
|
ldr r1, [tsk, #TI_FLAGS]
|
|
tst r1, #_TIF_WORK_MASK
|
|
bne work_pending
|
|
no_work_pending:
|
|
@ slow_restore_user_regs
|
|
ldr r1, [sp, #S_PSR] @ get calling cpsr
|
|
ldr lr, [sp, #S_PC]! @ get pc
|
|
msr spsr_cxsf, r1 @ save in spsr_svc
|
|
ldmdb sp, {r0 - lr}^ @ get calling r1 - lr
|
|
mov r0, r0
|
|
add sp, sp, #S_FRAME_SIZE - S_PC
|
|
movs pc, lr @ return & move spsr_svc into cpsr
|
|
|
|
/*
|
|
* This is how we return from a fork.
|
|
*/
|
|
ENTRY(ret_from_fork)
|
|
bl schedule_tail
|
|
get_thread_info tsk
|
|
ldr r1, [tsk, #TI_FLAGS] @ check for syscall tracing
|
|
mov why, #1
|
|
tst r1, #_TIF_SYSCALL_TRACE @ are we tracing syscalls?
|
|
beq ret_slow_syscall
|
|
mov r1, sp
|
|
mov r0, #1 @ trace exit [IP = 1]
|
|
bl syscall_trace
|
|
b ret_slow_syscall
|
|
|
|
|
|
#include "calls.S"
|
|
|
|
/*=============================================================================
|
|
* SWI handler
|
|
*-----------------------------------------------------------------------------
|
|
*/
|
|
|
|
/* If we're optimising for StrongARM the resulting code won't
|
|
run on an ARM7 and we can save a couple of instructions.
|
|
--pb */
|
|
#ifdef CONFIG_CPU_ARM710
|
|
.macro arm710_bug_check, instr, temp
|
|
and \temp, \instr, #0x0f000000 @ check for SWI
|
|
teq \temp, #0x0f000000
|
|
bne .Larm700bug
|
|
.endm
|
|
|
|
.Larm700bug:
|
|
ldr r0, [sp, #S_PSR] @ Get calling cpsr
|
|
sub lr, lr, #4
|
|
str lr, [r8]
|
|
msr spsr_cxsf, r0
|
|
ldmia sp, {r0 - lr}^ @ Get calling r0 - lr
|
|
mov r0, r0
|
|
ldr lr, [sp, #S_PC] @ Get PC
|
|
add sp, sp, #S_FRAME_SIZE
|
|
movs pc, lr
|
|
#else
|
|
.macro arm710_bug_check, instr, temp
|
|
.endm
|
|
#endif
|
|
|
|
.align 5
|
|
ENTRY(vector_swi)
|
|
sub sp, sp, #S_FRAME_SIZE
|
|
stmia sp, {r0 - r12} @ Calling r0 - r12
|
|
add r8, sp, #S_PC
|
|
stmdb r8, {sp, lr}^ @ Calling sp, lr
|
|
mrs r8, spsr @ called from non-FIQ mode, so ok.
|
|
str lr, [sp, #S_PC] @ Save calling PC
|
|
str r8, [sp, #S_PSR] @ Save CPSR
|
|
str r0, [sp, #S_OLD_R0] @ Save OLD_R0
|
|
zero_fp
|
|
|
|
/*
|
|
* Get the system call number.
|
|
*/
|
|
#ifdef CONFIG_ARM_THUMB
|
|
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
|
|
ldr scno, [lr, #-4] @ get SWI instruction
|
|
#endif
|
|
arm710_bug_check scno, ip
|
|
|
|
#ifdef CONFIG_ALIGNMENT_TRAP
|
|
ldr ip, __cr_alignment
|
|
ldr ip, [ip]
|
|
mcr p15, 0, ip, c1, c0 @ update control register
|
|
#endif
|
|
enable_irq
|
|
|
|
str r4, [sp, #-S_OFF]! @ push fifth arg
|
|
|
|
get_thread_info tsk
|
|
ldr ip, [tsk, #TI_FLAGS] @ check for syscall tracing
|
|
bic scno, scno, #0xff000000 @ mask off SWI op-code
|
|
eor scno, scno, #__NR_SYSCALL_BASE @ check OS number
|
|
adr tbl, sys_call_table @ load syscall table pointer
|
|
tst ip, #_TIF_SYSCALL_TRACE @ are we tracing syscalls?
|
|
bne __sys_trace
|
|
|
|
adr lr, ret_fast_syscall @ return address
|
|
cmp scno, #NR_syscalls @ check upper syscall limit
|
|
ldrcc pc, [tbl, scno, lsl #2] @ call sys_* routine
|
|
|
|
add r1, sp, #S_OFF
|
|
2: mov why, #0 @ no longer a real syscall
|
|
cmp scno, #(__ARM_NR_BASE - __NR_SYSCALL_BASE)
|
|
eor r0, scno, #__NR_SYSCALL_BASE @ put OS number back
|
|
bcs arm_syscall
|
|
b sys_ni_syscall @ not private func
|
|
|
|
/*
|
|
* This is the really slow path. We're going to be doing
|
|
* context switches, and waiting for our parent to respond.
|
|
*/
|
|
__sys_trace:
|
|
add r1, sp, #S_OFF
|
|
mov r0, #0 @ trace entry [IP = 0]
|
|
bl syscall_trace
|
|
|
|
adr lr, __sys_trace_return @ return address
|
|
add r1, sp, #S_R0 + S_OFF @ pointer to regs
|
|
cmp scno, #NR_syscalls @ check upper syscall limit
|
|
ldmccia r1, {r0 - r3} @ have to reload r0 - r3
|
|
ldrcc pc, [tbl, scno, lsl #2] @ call sys_* routine
|
|
b 2b
|
|
|
|
__sys_trace_return:
|
|
str r0, [sp, #S_R0 + S_OFF]! @ save returned r0
|
|
mov r1, sp
|
|
mov r0, #1 @ trace exit [IP = 1]
|
|
bl syscall_trace
|
|
b ret_slow_syscall
|
|
|
|
.align 5
|
|
#ifdef CONFIG_ALIGNMENT_TRAP
|
|
.type __cr_alignment, #object
|
|
__cr_alignment:
|
|
.word cr_alignment
|
|
#endif
|
|
|
|
.type sys_call_table, #object
|
|
ENTRY(sys_call_table)
|
|
#include "calls.S"
|
|
|
|
/*============================================================================
|
|
* Special system call wrappers
|
|
*/
|
|
@ r0 = syscall number
|
|
@ r5 = syscall table
|
|
.type sys_syscall, #function
|
|
sys_syscall:
|
|
eor scno, r0, #__NR_SYSCALL_BASE
|
|
cmp scno, #__NR_syscall - __NR_SYSCALL_BASE
|
|
cmpne scno, #NR_syscalls @ check range
|
|
stmloia sp, {r5, r6} @ shuffle args
|
|
movlo r0, r1
|
|
movlo r1, r2
|
|
movlo r2, r3
|
|
movlo r3, r4
|
|
ldrlo pc, [tbl, scno, lsl #2]
|
|
b sys_ni_syscall
|
|
|
|
sys_fork_wrapper:
|
|
add r0, sp, #S_OFF
|
|
b sys_fork
|
|
|
|
sys_vfork_wrapper:
|
|
add r0, sp, #S_OFF
|
|
b sys_vfork
|
|
|
|
sys_execve_wrapper:
|
|
add r3, sp, #S_OFF
|
|
b sys_execve
|
|
|
|
sys_clone_wrapper:
|
|
add ip, sp, #S_OFF
|
|
str ip, [sp, #4]
|
|
b sys_clone
|
|
|
|
sys_sigsuspend_wrapper:
|
|
add r3, sp, #S_OFF
|
|
b sys_sigsuspend
|
|
|
|
sys_rt_sigsuspend_wrapper:
|
|
add r2, sp, #S_OFF
|
|
b sys_rt_sigsuspend
|
|
|
|
sys_sigreturn_wrapper:
|
|
add r0, sp, #S_OFF
|
|
b sys_sigreturn
|
|
|
|
sys_rt_sigreturn_wrapper:
|
|
add r0, sp, #S_OFF
|
|
b sys_rt_sigreturn
|
|
|
|
sys_sigaltstack_wrapper:
|
|
ldr r2, [sp, #S_OFF + S_SP]
|
|
b do_sigaltstack
|
|
|
|
sys_futex_wrapper:
|
|
str r5, [sp, #4] @ push sixth arg
|
|
b sys_futex
|
|
|
|
/*
|
|
* Note: off_4k (r5) is always units of 4K. If we can't do the requested
|
|
* offset, we return EINVAL.
|
|
*/
|
|
sys_mmap2:
|
|
#if PAGE_SHIFT > 12
|
|
tst r5, #PGOFF_MASK
|
|
moveq r5, r5, lsr #PAGE_SHIFT - 12
|
|
streq r5, [sp, #4]
|
|
beq do_mmap2
|
|
mov r0, #-EINVAL
|
|
RETINSTR(mov,pc, lr)
|
|
#else
|
|
str r5, [sp, #4]
|
|
b do_mmap2
|
|
#endif
|