222 строки
5.1 KiB
ArmAsm
222 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 - 2000, 2001 by Ralf Baechle
|
|
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
|
|
* Copyright (C) 2001 MIPS Technologies, Inc.
|
|
* Copyright (C) 2004 Thiemo Seufer
|
|
*
|
|
* Hairy, the userspace application uses a different argument passing
|
|
* convention than the kernel, so we have to translate things from o32
|
|
* to ABI64 calling convention. 64-bit syscalls are also processed
|
|
* here for now.
|
|
*/
|
|
#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/thread_info.h>
|
|
#include <asm/unistd.h>
|
|
#include <asm/sysmips.h>
|
|
|
|
.align 5
|
|
NESTED(handle_sys, PT_SIZE, sp)
|
|
.set noat
|
|
SAVE_SOME
|
|
TRACE_IRQS_ON_RELOAD
|
|
STI
|
|
.set at
|
|
ld t1, PT_EPC(sp) # skip syscall on return
|
|
|
|
dsubu t0, v0, __NR_O32_Linux # check syscall number
|
|
sltiu t0, t0, __NR_O32_Linux_syscalls
|
|
daddiu t1, 4 # skip to next instruction
|
|
sd t1, PT_EPC(sp)
|
|
beqz t0, not_o32_scall
|
|
#if 0
|
|
SAVE_ALL
|
|
move a1, v0
|
|
PRINT("Scall %ld\n")
|
|
RESTORE_ALL
|
|
#endif
|
|
|
|
/* We don't want to stumble over broken sign extensions from
|
|
userland. O32 does never use the upper half. */
|
|
sll a0, a0, 0
|
|
sll a1, a1, 0
|
|
sll a2, a2, 0
|
|
sll a3, a3, 0
|
|
|
|
sd 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).
|
|
*
|
|
* 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.
|
|
*/
|
|
ld t0, PT_R29(sp) # get old user stack pointer
|
|
daddu t1, t0, 32
|
|
bltz t1, bad_stack
|
|
|
|
load_a4: lw a4, 16(t0) # argument #5 from usp
|
|
load_a5: lw a5, 20(t0) # argument #6 from usp
|
|
load_a6: lw a6, 24(t0) # argument #7 from usp
|
|
load_a7: lw a7, 28(t0) # argument #8 from usp
|
|
loads_done:
|
|
|
|
.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
|
|
|
|
li t1, _TIF_WORK_SYSCALL_ENTRY
|
|
LONG_L t0, TI_FLAGS($28) # syscall tracing enabled?
|
|
and t0, t1, t0
|
|
bnez t0, trace_a_syscall
|
|
|
|
syscall_common:
|
|
dsll t0, v0, 3 # offset into table
|
|
ld t2, (sys32_call_table - (__NR_O32_Linux * 8))(t0)
|
|
|
|
jalr t2 # Do The Real Thing (TM)
|
|
|
|
li t0, -EMAXERRNO - 1 # error?
|
|
sltu t0, t0, v0
|
|
sd t0, PT_R7(sp) # set error flag
|
|
beqz t0, 1f
|
|
|
|
ld t1, PT_R2(sp) # syscall number
|
|
dnegu v0 # error
|
|
sd t1, PT_R0(sp) # save it for syscall restarting
|
|
1: sd v0, PT_R2(sp) # result
|
|
|
|
o32_syscall_exit:
|
|
j syscall_exit_partial
|
|
|
|
/* ------------------------------------------------------------------------ */
|
|
|
|
trace_a_syscall:
|
|
SAVE_STATIC
|
|
sd a4, PT_R8(sp) # Save argument registers
|
|
sd a5, PT_R9(sp)
|
|
sd a6, PT_R10(sp)
|
|
sd a7, PT_R11(sp) # For indirect syscalls
|
|
|
|
move a0, sp
|
|
/*
|
|
* absolute syscall number is in v0 unless we called syscall(__NR_###)
|
|
* where the real syscall number is in a0
|
|
* note: NR_syscall is the first O32 syscall but the macro is
|
|
* only defined when compiling with -mabi=32 (CONFIG_32BIT)
|
|
* therefore __NR_O32_Linux is used (4000)
|
|
*/
|
|
.set push
|
|
.set reorder
|
|
subu t1, v0, __NR_O32_Linux
|
|
move a1, v0
|
|
bnez t1, 1f /* __NR_syscall at offset 0 */
|
|
ld a1, PT_R4(sp) /* Arg1 for __NR_syscall case */
|
|
.set pop
|
|
|
|
1: jal syscall_trace_enter
|
|
|
|
bltz v0, 1f # seccomp failed? Skip syscall
|
|
|
|
RESTORE_STATIC
|
|
ld v0, PT_R2(sp) # Restore syscall (maybe modified)
|
|
ld a0, PT_R4(sp) # Restore argument registers
|
|
ld a1, PT_R5(sp)
|
|
ld a2, PT_R6(sp)
|
|
ld a3, PT_R7(sp)
|
|
ld a4, PT_R8(sp)
|
|
ld a5, PT_R9(sp)
|
|
ld a6, PT_R10(sp)
|
|
ld a7, PT_R11(sp) # For indirect syscalls
|
|
|
|
dsubu t0, v0, __NR_O32_Linux # check (new) syscall number
|
|
sltiu t0, t0, __NR_O32_Linux_syscalls
|
|
beqz t0, not_o32_scall
|
|
|
|
j syscall_common
|
|
|
|
1: j syscall_exit
|
|
|
|
/* ------------------------------------------------------------------------ */
|
|
|
|
/*
|
|
* The stackpointer for a call with more than 4 arguments is bad.
|
|
*/
|
|
bad_stack:
|
|
li v0, EFAULT
|
|
sd v0, PT_R2(sp)
|
|
li t0, 1 # set error flag
|
|
sd t0, PT_R7(sp)
|
|
j o32_syscall_exit
|
|
|
|
bad_stack_a4:
|
|
li a4, 0
|
|
b load_a5
|
|
|
|
bad_stack_a5:
|
|
li a5, 0
|
|
b load_a6
|
|
|
|
bad_stack_a6:
|
|
li a6, 0
|
|
b load_a7
|
|
|
|
bad_stack_a7:
|
|
li a7, 0
|
|
b loads_done
|
|
|
|
not_o32_scall:
|
|
/*
|
|
* This is not an o32 compatibility syscall, pass it on
|
|
* to the 64-bit syscall handlers.
|
|
*/
|
|
#ifdef CONFIG_MIPS32_N32
|
|
j handle_sysn32
|
|
#else
|
|
j handle_sys64
|
|
#endif
|
|
END(handle_sys)
|
|
|
|
LEAF(sys32_syscall)
|
|
subu t0, a0, __NR_O32_Linux # check syscall number
|
|
sltiu v0, t0, __NR_O32_Linux_syscalls
|
|
beqz t0, einval # do not recurse
|
|
dsll t1, t0, 3
|
|
beqz v0, einval
|
|
ld t2, sys32_call_table(t1) # syscall routine
|
|
|
|
move a0, a1 # shift argument registers
|
|
move a1, a2
|
|
move a2, a3
|
|
move a3, a4
|
|
move a4, a5
|
|
move a5, a6
|
|
move a6, a7
|
|
jr t2
|
|
/* Unreached */
|
|
|
|
einval: li v0, -ENOSYS
|
|
jr ra
|
|
END(sys32_syscall)
|
|
|
|
#define __SYSCALL(nr, entry) PTR entry
|
|
.align 3
|
|
.type sys32_call_table,@object
|
|
EXPORT(sys32_call_table)
|
|
#include <asm/syscall_table_64_o32.h>
|
|
#undef __SYSCALL
|