[mirror_ubuntu-focal-kernel.git] / arch / mips / lib / strlen_user.S

/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (c) 1996, 1998, 1999, 2004 by Ralf Baechle
 * Copyright (c) 1999 Silicon Graphics, Inc.
 */
#include <asm/asm.h>
#include <asm/offset.h>
#include <asm/regdef.h>

#define EX(insn,reg,addr,handler)			\
9:	insn	reg, addr;				\
	.section __ex_table,"a";			\
	PTR	9b, handler;				\
	.previous

/*
 * Return the size of a string (including the ending 0)
 *
 * Return 0 for error
 */
LEAF(__strlen_user_asm)
	LONG_L		v0, TI_ADDR_LIMIT($28)	# pointer ok?
	and		v0, a0
	bnez		v0, fault

FEXPORT(__strlen_user_nocheck_asm)
	move		v0, a0
1:	EX(lb, t0, (v0), fault)
	PTR_ADDIU	v0, 1
	bnez		t0, 1b
	PTR_SUBU	v0, a0
	jr		ra
	END(__strlen_user_asm)

fault:	move		v0, zero
	jr		ra
Commit	Line	Data
1da177e4 LT	1	/*
	2	* This file is subject to the terms and conditions of the GNU General Public
	3	* License. See the file "COPYING" in the main directory of this archive
	4	* for more details.
	5	*
	6	* Copyright (c) 1996, 1998, 1999, 2004 by Ralf Baechle
	7	* Copyright (c) 1999 Silicon Graphics, Inc.
	8	*/
	9	#include <asm/asm.h>
	10	#include <asm/offset.h>
	11	#include <asm/regdef.h>
	12
	13	#define EX(insn,reg,addr,handler) \
	14	9: insn reg, addr; \
	15	.section __ex_table,"a"; \
	16	PTR 9b, handler; \
	17	.previous
	18
	19	/*
	20	* Return the size of a string (including the ending 0)
	21	*
	22	* Return 0 for error
	23	*/
	24	LEAF(__strlen_user_asm)
	25	LONG_L v0, TI_ADDR_LIMIT($28) # pointer ok?
	26	and v0, a0
	27	bnez v0, fault
	28
	29	FEXPORT(__strlen_user_nocheck_asm)
	30	move v0, a0
	31	1: EX(lb, t0, (v0), fault)
	32	PTR_ADDIU v0, 1
	33	bnez t0, 1b
	34	PTR_SUBU v0, a0
	35	jr ra
	36	END(__strlen_user_asm)
	37
	38	fault: move v0, zero
	39	jr ra