224 строки
5.1 KiB
ArmAsm
224 строки
5.1 KiB
ArmAsm
/*
|
|
* This file is subject to the terms and conditions of the GNU General Public
|
|
* License. See the file "COPYING" in the main directory of this archive
|
|
* for more details.
|
|
*
|
|
* Copyright (C) 1995-99, 2000- 02, 06 Ralf Baechle <ralf@linux-mips.org>
|
|
* Copyright (C) 2001 MIPS Technologies, Inc.
|
|
* Copyright (C) 2004 Thiemo Seufer
|
|
* Copyright (C) 2014 Imagination Technologies Ltd.
|
|
*/
|
|
#include <linux/errno.h>
|
|
#include <asm/asm.h>
|
|
#include <asm/asmmacro.h>
|
|
#include <asm/irqflags.h>
|
|
#include <asm/mipsregs.h>
|
|
#include <asm/regdef.h>
|
|
#include <asm/stackframe.h>
|
|
#include <asm/isadep.h>
|
|
#include <asm/sysmips.h>
|
|
#include <asm/thread_info.h>
|
|
#include <asm/unistd.h>
|
|
#include <asm/war.h>
|
|
#include <asm/asm-offsets.h>
|
|
|
|
.align 5
|
|
NESTED(handle_sys, PT_SIZE, sp)
|
|
.set noat
|
|
SAVE_SOME
|
|
TRACE_IRQS_ON_RELOAD
|
|
STI
|
|
.set at
|
|
|
|
lw t1, PT_EPC(sp) # skip syscall on return
|
|
|
|
addiu t1, 4 # skip to next instruction
|
|
sw t1, PT_EPC(sp)
|
|
|
|
sw a3, PT_R26(sp) # save a3 for syscall restarting
|
|
|
|
/*
|
|
* More than four arguments. Try to deal with it by copying the
|
|
* stack arguments from the user stack to the kernel stack.
|
|
* This Sucks (TM).
|
|
*/
|
|
lw t0, PT_R29(sp) # get old user stack pointer
|
|
|
|
/*
|
|
* We intentionally keep the kernel stack a little below the top of
|
|
* userspace so we don't have to do a slower byte accurate check here.
|
|
*/
|
|
addu t4, t0, 32
|
|
bltz t4, bad_stack # -> sp is bad
|
|
|
|
/*
|
|
* Ok, copy the args from the luser stack to the kernel stack.
|
|
*/
|
|
|
|
.set push
|
|
.set noreorder
|
|
.set nomacro
|
|
|
|
load_a4: user_lw(t5, 16(t0)) # argument #5 from usp
|
|
load_a5: user_lw(t6, 20(t0)) # argument #6 from usp
|
|
load_a6: user_lw(t7, 24(t0)) # argument #7 from usp
|
|
load_a7: user_lw(t8, 28(t0)) # argument #8 from usp
|
|
loads_done:
|
|
|
|
sw t5, 16(sp) # argument #5 to ksp
|
|
sw t6, 20(sp) # argument #6 to ksp
|
|
sw t7, 24(sp) # argument #7 to ksp
|
|
sw t8, 28(sp) # argument #8 to ksp
|
|
.set pop
|
|
|
|
.section __ex_table,"a"
|
|
PTR load_a4, bad_stack_a4
|
|
PTR load_a5, bad_stack_a5
|
|
PTR load_a6, bad_stack_a6
|
|
PTR load_a7, bad_stack_a7
|
|
.previous
|
|
|
|
lw t0, TI_FLAGS($28) # syscall tracing enabled?
|
|
li t1, _TIF_WORK_SYSCALL_ENTRY
|
|
and t0, t1
|
|
bnez t0, syscall_trace_entry # -> yes
|
|
syscall_common:
|
|
subu v0, v0, __NR_O32_Linux # check syscall number
|
|
sltiu t0, v0, __NR_O32_Linux_syscalls
|
|
beqz t0, illegal_syscall
|
|
|
|
sll t0, v0, 2
|
|
la t1, sys_call_table
|
|
addu t1, t0
|
|
lw t2, (t1) # syscall routine
|
|
|
|
beqz t2, illegal_syscall
|
|
|
|
jalr t2 # Do The Real Thing (TM)
|
|
|
|
li t0, -EMAXERRNO - 1 # error?
|
|
sltu t0, t0, v0
|
|
sw t0, PT_R7(sp) # set error flag
|
|
beqz t0, 1f
|
|
|
|
lw t1, PT_R2(sp) # syscall number
|
|
negu v0 # error
|
|
sw t1, PT_R0(sp) # save it for syscall restarting
|
|
1: sw v0, PT_R2(sp) # result
|
|
|
|
o32_syscall_exit:
|
|
j syscall_exit_partial
|
|
|
|
/* ------------------------------------------------------------------------ */
|
|
|
|
syscall_trace_entry:
|
|
SAVE_STATIC
|
|
move a0, sp
|
|
|
|
/*
|
|
* syscall number is in v0 unless we called syscall(__NR_###)
|
|
* where the real syscall number is in a0
|
|
*/
|
|
move a1, v0
|
|
subu t2, v0, __NR_O32_Linux
|
|
bnez t2, 1f /* __NR_syscall at offset 0 */
|
|
lw a1, PT_R4(sp)
|
|
|
|
1: jal syscall_trace_enter
|
|
|
|
bltz v0, 1f # seccomp failed? Skip syscall
|
|
|
|
RESTORE_STATIC
|
|
lw v0, PT_R2(sp) # Restore syscall (maybe modified)
|
|
lw a0, PT_R4(sp) # Restore argument registers
|
|
lw a1, PT_R5(sp)
|
|
lw a2, PT_R6(sp)
|
|
lw a3, PT_R7(sp)
|
|
j syscall_common
|
|
|
|
1: j syscall_exit
|
|
|
|
/* ------------------------------------------------------------------------ */
|
|
|
|
/*
|
|
* Our open-coded access area sanity test for the stack pointer
|
|
* failed. We probably should handle this case a bit more drastic.
|
|
*/
|
|
bad_stack:
|
|
li v0, EFAULT
|
|
sw v0, PT_R2(sp)
|
|
li t0, 1 # set error flag
|
|
sw t0, PT_R7(sp)
|
|
j o32_syscall_exit
|
|
|
|
bad_stack_a4:
|
|
li t5, 0
|
|
b load_a5
|
|
|
|
bad_stack_a5:
|
|
li t6, 0
|
|
b load_a6
|
|
|
|
bad_stack_a6:
|
|
li t7, 0
|
|
b load_a7
|
|
|
|
bad_stack_a7:
|
|
li t8, 0
|
|
b loads_done
|
|
|
|
/*
|
|
* The system call does not exist in this kernel
|
|
*/
|
|
illegal_syscall:
|
|
li v0, ENOSYS # error
|
|
sw v0, PT_R2(sp)
|
|
li t0, 1 # set error flag
|
|
sw t0, PT_R7(sp)
|
|
j o32_syscall_exit
|
|
END(handle_sys)
|
|
|
|
LEAF(sys_syscall)
|
|
subu t0, a0, __NR_O32_Linux # check syscall number
|
|
sltiu v0, t0, __NR_O32_Linux_syscalls
|
|
beqz t0, einval # do not recurse
|
|
sll t1, t0, 2
|
|
beqz v0, einval
|
|
lw t2, sys_call_table(t1) # syscall routine
|
|
|
|
move a0, a1 # shift argument registers
|
|
move a1, a2
|
|
move a2, a3
|
|
lw a3, 16(sp)
|
|
lw t4, 20(sp)
|
|
lw t5, 24(sp)
|
|
lw t6, 28(sp)
|
|
sw t4, 16(sp)
|
|
sw t5, 20(sp)
|
|
sw t6, 24(sp)
|
|
jr t2
|
|
/* Unreached */
|
|
|
|
einval: li v0, -ENOSYS
|
|
jr ra
|
|
END(sys_syscall)
|
|
|
|
#ifdef CONFIG_MIPS_MT_FPAFF
|
|
/*
|
|
* For FPU affinity scheduling on MIPS MT processors, we need to
|
|
* intercept sys_sched_xxxaffinity() calls until we get a proper hook
|
|
* in kernel/sched/core.c. Considered only temporary we only support
|
|
* these hooks for the 32-bit kernel - there is no MIPS64 MT processor
|
|
* atm.
|
|
*/
|
|
#define sys_sched_setaffinity mipsmt_sys_sched_setaffinity
|
|
#define sys_sched_getaffinity mipsmt_sys_sched_getaffinity
|
|
#endif /* CONFIG_MIPS_MT_FPAFF */
|
|
|
|
#define __SYSCALL_WITH_COMPAT(nr, native, compat) __SYSCALL(nr, native)
|
|
#define __SYSCALL(nr, entry) PTR entry
|
|
.align 2
|
|
.type sys_call_table, @object
|
|
EXPORT(sys_call_table)
|
|
#include <asm/syscall_table_o32.h>
|