[mirror_ubuntu-zesty-kernel.git] / arch / sparc / lib / strncpy_from_user_32.S

/* strncpy_from_user.S: Sparc strncpy from userspace.
 *
 *  Copyright(C) 1996 David S. Miller
 */

#include <linux/linkage.h>
#include <asm/ptrace.h>
#include <asm/errno.h>

	.text

	/* Must return:
	 *
	 * -EFAULT		for an exception
	 * count		if we hit the buffer limit
	 * bytes copied		if we hit a null byte
	 */

ENTRY(__strncpy_from_user)
	/* %o0=dest, %o1=src, %o2=count */
	mov	%o2, %o3
1:
	subcc	%o2, 1, %o2
	bneg	2f
	 nop
10:
	ldub	[%o1], %o4
	add	%o0, 1, %o0
	cmp	%o4, 0
	add	%o1, 1, %o1
	bne	1b
	 stb	%o4, [%o0 - 1]
2:
	add	%o2, 1, %o0
	retl
	 sub	%o3, %o0, %o0
ENDPROC(__strncpy_from_user)

	.section .fixup,#alloc,#execinstr
	.align	4
4:
	retl
	 mov	-EFAULT, %o0

	.section __ex_table,#alloc
	.align	4
	.word	10b, 4b
Commit	Line	Data
1da177e4 LT	1	/* strncpy_from_user.S: Sparc strncpy from userspace.
	2	*
	3	* Copyright(C) 1996 David S. Miller
	4	*/
	5
8695c37d	6	#include <linux/linkage.h>
1da177e4 LT	7	#include <asm/ptrace.h>
	8	#include <asm/errno.h>
	9
	10	.text
1da177e4 LT	11
	12	/* Must return:
	13	*
	14	* -EFAULT for an exception
	15	* count if we hit the buffer limit
	16	* bytes copied if we hit a null byte
	17	*/
	18
8695c37d	19	ENTRY(__strncpy_from_user)
1da177e4 LT	20	/* %o0=dest, %o1=src, %o2=count */
	21	mov %o2, %o3
	22	1:
	23	subcc %o2, 1, %o2
	24	bneg 2f
	25	nop
	26	10:
	27	ldub [%o1], %o4
	28	add %o0, 1, %o0
	29	cmp %o4, 0
	30	add %o1, 1, %o1
	31	bne 1b
	32	stb %o4, [%o0 - 1]
	33	2:
	34	add %o2, 1, %o0
	35	retl
	36	sub %o3, %o0, %o0
8695c37d	37	ENDPROC(__strncpy_from_user)
1da177e4 LT	38
	39	.section .fixup,#alloc,#execinstr
	40	.align 4
	41	4:
	42	retl
	43	mov -EFAULT, %o0
	44
	45	.section __ex_table,#alloc
	46	.align 4
	47	.word 10b, 4b