projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 77c93b2f G |
1 | /* |
| 2 | * linux/arch/unicore32/lib/strncpy_from_user.S | |
| 3 | * | |
| 4 | * Code specific to PKUnity SoC and UniCore ISA | |
| 5 | * | |
| 6 | * Copyright (C) 2001-2010 GUAN Xue-tao | |
| 7 | * | |
| 8 | * This program is free software; you can redistribute it and/or modify | |
| 9 | * it under the terms of the GNU General Public License version 2 as | |
| 10 | * published by the Free Software Foundation. | |
| 11 | */ | |
| 12 | #include <linux/linkage.h> | |
| 13 | #include <asm/assembler.h> | |
| 14 | #include <asm/errno.h> | |
| 15 | ||
| 16 | .text | |
| 17 | .align 5 | |
| 18 | ||
| 19 | /* | |
| 20 | * Copy a string from user space to kernel space. | |
| 21 | * r0 = dst, r1 = src, r2 = byte length | |
| 22 | * returns the number of characters copied (strlen of copied string), | |
| 23 | * -EFAULT on exception, or "len" if we fill the whole buffer | |
| 24 | */ | |
| 25 | ENTRY(__strncpy_from_user) | |
| 26 | mov ip, r1 | |
| 27 | 1: sub.a r2, r2, #1 | |
| 28 | ldrusr r3, r1, 1, ns | |
| 29 | bfs 2f | |
| 30 | stb.w r3, [r0]+, #1 | |
| 31 | cxor.a r3, #0 | |
| 32 | bne 1b | |
| 33 | sub r1, r1, #1 @ take NUL character out of count | |
| 34 | 2: sub r0, r1, ip | |
| 35 | mov pc, lr | |
| 36 | ENDPROC(__strncpy_from_user) | |
| 37 | ||
| 38 | .pushsection .fixup,"ax" | |
| 39 | .align 0 | |
| 40 | 9001: mov r3, #0 | |
| 41 | stb r3, [r0+], #0 @ null terminate | |
| 42 | mov r0, #-EFAULT | |
| 43 | mov pc, lr | |
| 44 | .popsection | |
| 45 |