/*
   * 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, 1999 by Ralf Baechle
   */
  #include <linux/errno.h>
  #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;				\
  	.previous
  
  /*
   * Returns: -EFAULT if exception before terminator, N if the entire
   * buffer filled, else strlen.
   */
  
  /*
   * Ugly special case have to check: we might get passed a user space
   * pointer which wraps into the kernel space.  We don't deal with that.  If
   * it happens at most some bytes of the exceptions handlers will be copied.
   */
  
  LEAF(__strncpy_from_user_asm)
  	LONG_L		v0, TI_ADDR_LIMIT($28)	# pointer ok?
  	and		v0, a1

  	bnez		v0, .Lfault

  
  FEXPORT(__strncpy_from_user_nocheck_asm)
  	move		v0, zero
  	move		v1, a1
  	.set		noreorder

  1:	EX(lbu, t0, (v1), .Lfault)

  	PTR_ADDIU	v1, 1

  	R10KCBARRIER(0(ra))

  	beqz		t0, 2f
  	 sb		t0, (a0)
  	PTR_ADDIU	v0, 1

  	.set		reorder

  	PTR_ADDIU	a0, 1
  	bne		v0, a2, 1b

  2:	PTR_ADDU	t0, a1, v0
  	xor		t0, a1

  	bltz		t0, .Lfault

  	jr		ra			# return n
  	END(__strncpy_from_user_asm)

  .Lfault:	li		v0, -EFAULT

  	jr		ra
  
  	.section	__ex_table,"a"

  	PTR		1b, .Lfault

  	.previous