blob: fcacea5e61f1e685891e8e4af7ec8f701c596fd2 [file] [log] [blame]
* 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/asm-offsets.h>
#include <asm/regdef.h>
#define EX(insn,reg,addr,handler) \
9: insn reg, addr; \
.section __ex_table,"a"; \
PTR 9b, handler; \
* Return the size of a string including the ending NUL character up to a
* maximum of a1 or 0 in case of error.
* Note: for performance reasons we deliberately accept that a user may
* make strlen_user and strnlen_user access the first few KSEG0
* bytes. There's nothing secret there. On 64-bit accessing beyond
* the maximum is a tad hairier ...
LONG_L v0, TI_ADDR_LIMIT($28) # pointer ok?
and v0, a0
bnez v0, .Lfault
move v0, a0
PTR_ADDU a1, a0 # stop pointer
1: beq v0, a1, 1f # limit reached?
EX(lb, t0, (v0), .Lfault)
bnez t0, 1b
1: PTR_SUBU v0, a0
jr ra
move v0, zero
jr ra