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/*

 * 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 

#include 

#include 

#include 

#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)

        lw      v0, THREAD_CURDS($28)   # pointer ok?

        and     v0, a1

        bltz    v0, fault

EXPORT(__strncpy_from_user_nocheck_asm)

        move    v0, zero

        move    v1, a1

        .set    noreorder

1:      EX(lbu,  t0, (v1), fault)

        addiu   v1, v1, 1

        beqz    t0, 2f

         sb     t0, (a0)

        addiu   v0, 1

        bne     v0, a2, 1b

         addiu  a0, 1

        .set    reorder

2:      addu    t0, a1, v0

        xor     t0, a1

        bltz    t0, fault

        jr      ra                              # return n

        END(__strncpy_from_user_asm)

fault:  li      v0, -EFAULT

        jr      ra

        .section __ex_table,"a"

        PTR     1b, fault

        .previous