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/*
 * __put_user functions.
 *
 * (C) Copyright 1998 Linus Torvalds
 *
 * These functions have a non-standard call interface
 * to make them more efficient.
 */

/*
 * __put_user_X
 *
 * Inputs:      %rax contains the address
 *              %rdx contains the value
 *
 * Outputs:     %rax is error code (0 or -EFAULT)
 *              %rbx is corrupted (will contain "current_task").
 *
 * These functions should not modify any other registers,
 * as they get called from within inline assembly.
 */

/* FIXME: putuser.S should be really merged with getuser.S, and preprocessor should be used to keep code duplication lower */

#include <linux/linkage.h>
#include <asm/page.h>
#include <asm/errno.h>
#include <asm/current.h>
#include <asm/offset.h>

.text
.p2align
.globl __put_user_1
__put_user_1:
        GET_CURRENT(%rbx)
        cmpq tsk_addr_limit(%rbx),%rax
        jae bad_put_user
1:      movb %dl,(%rax)
        xorq %rax,%rax
        ret

.p2align
.globl __put_user_2
__put_user_2:
        GET_CURRENT(%rbx) 
        addq $1,%rax
        jc              bad_put_user
        cmpq    tsk_addr_limit(%rbx),%rax
        jae     bad_put_user
2:      movw %dx,-1(%rax)
        xorq %rax,%rax
        ret

.p2align
.globl __put_user_4
__put_user_4:
        GET_CURRENT(%rbx) 
        addq $3,%rax
        jc              bad_put_user
        cmpq    tsk_addr_limit(%rbx),%rax
        jae     bad_put_user
3:      movl %edx,-3(%rax)
        xorq %rax,%rax
        ret

.p2align
.globl __put_user_8
__put_user_8:
        GET_CURRENT(%rbx) 
        addq $7,%rax
        jc      bad_put_user
        cmpq    tsk_addr_limit(%rbx),%rax
        jae     bad_put_user
4:      movq %rdx,-7(%rax)
        xorq %rax,%rax
        ret

ENTRY(bad_put_user)     
bad_put_user:
        movq $(-EFAULT),%rax
        ret

.section __ex_table,"a"
        .quad 1b,bad_put_user
        .quad 2b,bad_put_user
        .quad 3b,bad_put_user
        .quad 4b,bad_put_user   
.previous