| /* |
| * linux/arch/unicore32/lib/strncpy_from_user.S |
| * |
| * Code specific to PKUnity SoC and UniCore ISA |
| * |
| * Copyright (C) 2001-2010 GUAN Xue-tao |
| * |
| * 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 <linux/linkage.h> |
| #include <asm/assembler.h> |
| #include <asm/errno.h> |
| |
| .text |
| .align 5 |
| |
| /* |
| * Copy a string from user space to kernel space. |
| * r0 = dst, r1 = src, r2 = byte length |
| * returns the number of characters copied (strlen of copied string), |
| * -EFAULT on exception, or "len" if we fill the whole buffer |
| */ |
| ENTRY(__strncpy_from_user) |
| mov ip, r1 |
| 1: sub.a r2, r2, #1 |
| ldrusr r3, r1, 1, ns |
| bfs 2f |
| stb.w r3, [r0]+, #1 |
| cxor.a r3, #0 |
| bne 1b |
| sub r1, r1, #1 @ take NUL character out of count |
| 2: sub r0, r1, ip |
| mov pc, lr |
| ENDPROC(__strncpy_from_user) |
| |
| .pushsection .fixup,"ax" |
| .align 0 |
| 9001: mov r3, #0 |
| stb r3, [r0+], #0 @ null terminate |
| mov r0, #-EFAULT |
| mov pc, lr |
| .popsection |
| |
