| /* |
| * 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 |
| rcall __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 |