| /* |
| * 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 |
| |
| sys_arm_fadvise64_64_wrapper: |
| str r5, [sp, #4] @ push r5 to stack |
| b sys_arm_fadvise64_64 |
| |
| sys_mbind_wrapper: |
| str r5, [sp, #4] |
| b sys_mbind |
| |
| /* |
| * 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 |