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#include <linux/config.h>
/*============================================================================
* All exits to user mode from the kernel go through this code.
*/
/*
* Define to favour ARM8, ARM9 and StrongARM cpus. This says that it is
* cheaper to use two LDR instructions than a two-register LDM, if the
* latter would entail calculating an address specially.
*/
#if defined(CONFIG_CPU_SA110)
#define HARVARD_CACHE
#endif
.globl ret_from_sys_call
.align 5
fast_syscall_return:
str r0, [sp, #S_R0 + 4] @ returned r0
slow_syscall_return:
add sp, sp, #4
ret_from_sys_call:
#ifdef HARVARD_CACHE
ldr r0, bh_data
ldr r4, bh_data+4
#else
adr r0, bh_data
ldmia r0, {r0, r4}
#endif
ldr r0, [r0]
ldr r1, [r4]
tst r0, r1
blne SYMBOL_NAME(do_bottom_half)
ret_with_reschedule:
get_current_task r5
ldr r0, [r5, #TSK_NEED_RESCHED]
ldr r1, [r5, #TSK_SIGPENDING]
teq r0, #0
bne ret_reschedule
teq r1, #0 @ check for signals
bne ret_signal
ret_from_all: restore_user_regs
ret_signal: mov r1, sp
adrsvc al, lr, ret_from_all
mov r2, r4
b SYMBOL_NAME(do_signal)
ret_reschedule: adrsvc al, lr, ret_with_reschedule
b SYMBOL_NAME(schedule)
.globl ret_from_exception
ret_from_exception:
#ifdef HARVARD_CACHE
ldr r0, bh_data
ldr r1, bh_data + 4
#else
adr r0, bh_data
ldmia r0, {r0, r1}
#endif
ldr r0, [r0]
ldr r1, [r1]
mov r4, #0
tst r0, r1
blne SYMBOL_NAME(do_bottom_half)
ldr r0, [sp, #S_PSR]
tst r0, #3 @ returning to user mode?
beq ret_with_reschedule
b ret_from_all
#include "calls.S"
/*=============================================================================
* SWI handler
*-----------------------------------------------------------------------------
*
* We now handle sys-call tracing, and the errno in the task structure.
* Still have a problem with >4 arguments for functions. Theres only
* a couple of functions in the code that have 5 arguments, so Im not
* too worried.
*/
.align 5
vector_swi: save_user_regs
mask_pc lr, lr
mov fp, #0
ldr r6, [lr, #-4] @ get SWI instruction
arm700_bug_check r6, r7
#ifdef CONFIG_ALIGNMENT_TRAP
ldr r7, .LCswi
ldr r7, [r7]
mcr p15, 0, r7, c1, c0
#endif
enable_irqs r7
str r4, [sp, #-4]! @ new style: (r0 = arg1, r4 = arg5)
adrsvc al, lr, fast_syscall_return
bic r6, r6, #0xff000000 @ mask off SWI op-code
eor r6, r6, #OS_NUMBER<<20 @ check OS number
cmp r6, #NR_syscalls @ check upper syscall limit
bcs 2f
get_current_task r7
ldr ip, [r7, #TSK_FLAGS] @ check for syscall tracing
adr r5, SYMBOL_NAME(sys_call_table)
tst ip, #PF_TRACESYS
ldreq pc, [r5, r6, lsl #2] @ call sys routine
ldr r7, [sp, #S_IP + 4] @ save old IP
mov r0, #0
str r0, [sp, #S_IP + 4] @ trace entry [IP = 0]
bl SYMBOL_NAME(syscall_trace)
str r7, [sp, #S_IP + 4]
ldmib sp, {r0 - r3} @ have to reload r0 - r3
mov lr, pc
ldr pc, [r5, r6, lsl #2] @ call sys routine
str r0, [sp, #S_R0 + 4] @ returned r0
mov r0, #1
str r0, [sp, #S_IP + 4] @ trace exit [IP = 1]
bl SYMBOL_NAME(syscall_trace)
str r7, [sp, #S_IP + 4]
b slow_syscall_return
2: add r1, sp, #4
tst r6, #0x00f00000 @ is it a Unix SWI?
bne 3f
subs r0, r6, #(KSWI_SYS_BASE - KSWI_BASE)
bcs SYMBOL_NAME(arm_syscall)
b SYMBOL_NAME(sys_ni_syscall) @ not private func
3: eor r0, r6, #OS_NUMBER <<20 @ Put OS number back
adrsvc al, lr, slow_syscall_return
b SYMBOL_NAME(deferred)
.align 5
bh_data: .word SYMBOL_NAME(bh_mask)
.word SYMBOL_NAME(bh_active)
ENTRY(sys_call_table)
#include "calls.S"
/*============================================================================
* Special system call wrappers
*/
@ r0 = syscall number
@ r5 = syscall table
SYMBOL_NAME(sys_syscall):
eor r6, r0, #OS_NUMBER << 20
cmp r6, #NR_syscalls @ check range
add ip, sp, #4
ldmleib ip, {r0 - r4} @ get our args
strle r4, [sp] @ Put our arg on the stack
ldrle pc, [r5, r6, lsl #2]
mov r0, #-ENOSYS
mov pc, lr
sys_fork_wrapper:
add r0, sp, #4
b SYMBOL_NAME(sys_fork)
sys_vfork_wrapper:
add r0, sp, #4
b SYMBOL_NAME(sys_vfork)
sys_execve_wrapper:
add r3, sp, #4
b SYMBOL_NAME(sys_execve)
sys_mount_wrapper:
mov r6, lr
add r5, sp, #4
str r5, [sp]
str r4, [sp, #-4]!
bl SYMBOL_NAME(sys_compat_mount)
add sp, sp, #4
RETINSTR(mov,pc,r6)
sys_clone_wapper:
add r2, sp, #4
b SYMBOL_NAME(sys_clone)
sys_llseek_wrapper:
mov r6, lr
add r5, sp, #4
str r5, [sp]
str r4, [sp, #-4]!
bl SYMBOL_NAME(sys_compat_llseek)
add sp, sp, #4
RETINSTR(mov,pc,r6)
sys_sigsuspend_wrapper:
add r3, sp, #4
b SYMBOL_NAME(sys_sigsuspend)
sys_rt_sigsuspend_wrapper:
add r2, sp, #4
b SYMBOL_NAME(sys_rt_sigsuspend)
sys_sigreturn_wrapper:
add r0, sp, #4
b SYMBOL_NAME(sys_sigreturn)
sys_rt_sigreturn_wrapper:
add r0, sp, #4
b SYMBOL_NAME(sys_rt_sigreturn)
sys_sigaltstack_wrapper:
ldr r2, [sp, #4 + S_SP]
b do_sigaltstack
.data
ENTRY(fp_enter)
.word fpe_not_present
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