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/*

 * __get_user functions.

 *

 * (C) Copyright 1998 Linus Torvalds

 *

 * These functions have a non-standard call interface

 * to make them more efficient, especially as they

 * return an error value in addition to the "real"

 * return value.

 */

/*

 * __get_user_X

 *

 * Inputs:      %rax contains the address

 *

 * Outputs:     %rax is error code (0 or -EFAULT)

 *              %rdx contains zero-extended value

 *

 * %rbx is destroyed.

 *

 * These functions should not modify any other registers,

 * as they get called from within inline assembly.

 */

#include 

#include 

#include 

#include 

#include 

#include 

        .text

        .p2align

.globl __get_user_1

__get_user_1:

        GET_CURRENT(%rbx)

        cmpq tsk_addr_limit(%rbx),%rax

        jae bad_get_user

1:      movzb (%rax),%edx

        xorq %rax,%rax

        ret

        .p2align

.globl __get_user_2

__get_user_2:

        GET_CURRENT(%rbx)

        addq $1,%rax

        jc bad_get_user

        cmpq tsk_addr_limit(%rbx),%rax

        jae      bad_get_user

2:      movzwl -1(%rax),%edx

        xorq %rax,%rax

        ret

        .p2align

.globl __get_user_4

__get_user_4:

        GET_CURRENT(%rbx)

        addq $3,%rax

        jc bad_get_user

        cmpq tsk_addr_limit(%rbx),%rax

        jae bad_get_user

3:      movl -3(%rax),%edx

        xorq %rax,%rax

        ret

        .p2align

.globl __get_user_8

__get_user_8:

        GET_CURRENT(%rbx)

        addq $7,%rax

        jc bad_get_user

        cmpq tsk_addr_limit(%rbx),%rax

        jae     bad_get_user

4:      movq -7(%rax),%rdx

        xorq %rax,%rax

        ret

ENTRY(bad_get_user)

bad_get_user:

        xorq %rdx,%rdx

        movq $(-EFAULT),%rax

        ret

.section __ex_table,"a"

        .quad 1b,bad_get_user

        .quad 2b,bad_get_user

        .quad 3b,bad_get_user

        .quad 4b,bad_get_user

.previous