|  | /* | 
|  | *  linux/arch/arm/lib/strncpy_from_user.S | 
|  | * | 
|  | *  Copyright (C) 1995-2000 Russell King | 
|  | * | 
|  | * 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:	subs	r2, r2, #1 | 
|  | USER(	ldrplbt	r3, [r1], #1) | 
|  | bmi	2f | 
|  | strb	r3, [r0], #1 | 
|  | teq	r3, #0 | 
|  | bne	1b | 
|  | sub	r1, r1, #1	@ take NUL character out of count | 
|  | 2:	sub	r0, r1, ip | 
|  | mov	pc, lr | 
|  |  | 
|  | .section .fixup,"ax" | 
|  | .align	0 | 
|  | 9001:	mov	r3, #0 | 
|  | strb	r3, [r0, #0]	@ null terminate | 
|  | mov	r0, #-EFAULT | 
|  | mov	pc, lr | 
|  | .previous | 
|  |  |