linux/arch/avr32/lib/strnlen_user.S
Ben Nizette 8d29b7b9f8 avr32: Fix out-of-range rcalls in large kernels
Replace handcoded rcall instructions with the call pseudo-instruction.
For kernels too far over 1MB the rcall instruction can't reach and
linking will fail.  We already call the final linker with --relax which
converts call pseudo-instructions to the right things anyway.

This fixes

arch/avr32/kernel/built-in.o: In function `syscall_exit_work':
(.ex.text+0x198): relocation truncated to fit: R_AVR32_22H_PCREL against symbol `schedule' defined in .sched.text section in kernel/built-in.o
arch/avr32/kernel/built-in.o: In function `fault_exit_work':
(.ex.text+0x3b6): relocation truncated to fit: R_AVR32_22H_PCREL against symbol `schedule' defined in .sched.text section in kernel/built-in.o

But I'm still left with

arch/avr32/kernel/built-in.o:(.fixup+0x2): relocation truncated to fit: R_AVR32_22H_PCREL against `.text'+45a
arch/avr32/kernel/built-in.o:(.fixup+0x8): relocation truncated to fit: R_AVR32_22H_PCREL against `.text'+8ea
arch/avr32/kernel/built-in.o:(.fixup+0xe): relocation truncated to fit: R_AVR32_22H_PCREL against `.text'+abe
arch/avr32/kernel/built-in.o:(.fixup+0x14): relocation truncated to fit: R_AVR32_22H_PCREL against `.text'+ac8
arch/avr32/kernel/built-in.o:(.fixup+0x1a): relocation truncated to fit: R_AVR32_22H_PCREL against `.text'+ad2
arch/avr32/kernel/built-in.o:(.fixup+0x20): relocation truncated to fit: R_AVR32_22H_PCREL against `.text'+adc
arch/avr32/kernel/built-in.o:(.fixup+0x26): relocation truncated to fit: R_AVR32_22H_PCREL against `.text'+ae6
arch/avr32/kernel/built-in.o:(.fixup+0x2c): relocation truncated to fit: R_AVR32_22H_PCREL against `.text'+af0
arch/avr32/kernel/built-in.o:(.fixup+0x32): additional relocation overflows omitted from the output

These are caused by a similar problem with 'rjmp' instructions.
Unfortunately, there's no easy fix for these at the moment since we
don't have a arbitrary-range 'jmp' instruction similar to 'call'.

Signed-off-by: Ben Nizette <bn@niasdigital.com>
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
2009-01-16 09:31:57 +01:00

68 lines
1.2 KiB
ArmAsm

/*
* Copy to/from userspace with optional address space checking.
*
* Copyright 2004-2006 Atmel Corporation
*
* 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 <asm/page.h>
#include <asm/thread_info.h>
#include <asm/processor.h>
#include <asm/asm.h>
.text
.align 1
.global strnlen_user
.type strnlen_user, "function"
strnlen_user:
branch_if_kernel r8, __strnlen_user
sub r8, r11, 1
add r8, r12
retcs 0
brmi adjust_length /* do a closer inspection */
.global __strnlen_user
.type __strnlen_user, "function"
__strnlen_user:
mov r10, r12
10: ld.ub r8, r12++
cp.w r8, 0
breq 2f
sub r11, 1
brne 10b
sub r12, -1
2: sub r12, r10
retal r12
.type adjust_length, "function"
adjust_length:
cp.w r12, 0 /* addr must always be < TASK_SIZE */
retmi 0
pushm lr
lddpc lr, _task_size
sub r11, lr, r12
mov r9, r11
call __strnlen_user
cp.w r12, r9
brgt 1f
popm pc
1: popm pc, r12=0
.align 2
_task_size:
.long TASK_SIZE
.section .fixup, "ax"
.align 1
19: retal 0
.section __ex_table, "a"
.align 2
.long 10b, 19b