| /* | |
| * 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 |