Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/*
 * __put_user functions.
 *
 * (C) Copyright 2005 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.
 */
#include <linux/linkage.h>
#include <asm/dwarf2.h>
#include <asm/thread_info.h>


/*
 * __put_user_X
 *
 * Inputs:      %eax[:%edx] contains the data
 *              %ecx contains the address
 *
 * Outputs:     %eax is error code (0 or -EFAULT)
 *
 * These functions should not modify any other registers,
 * as they get called from within inline assembly.
 */

#define ENTER   CFI_STARTPROC ; \
                pushl %ebx ; \
                CFI_ADJUST_CFA_OFFSET 4 ; \
                CFI_REL_OFFSET ebx, 0 ; \
                GET_THREAD_INFO(%ebx)
#define EXIT    popl %ebx ; \
                CFI_ADJUST_CFA_OFFSET -4 ; \
                CFI_RESTORE ebx ; \
                ret ; \
                CFI_ENDPROC

.text
ENTRY(__put_user_1)
        ENTER
        cmpl TI_addr_limit(%ebx),%ecx
        jae bad_put_user
1:      movb %al,(%ecx)
        xorl %eax,%eax
        EXIT
ENDPROC(__put_user_1)

ENTRY(__put_user_2)
        ENTER
        movl TI_addr_limit(%ebx),%ebx
        subl $1,%ebx
        cmpl %ebx,%ecx
        jae bad_put_user
2:      movw %ax,(%ecx)
        xorl %eax,%eax
        EXIT
ENDPROC(__put_user_2)

ENTRY(__put_user_4)
        ENTER
        movl TI_addr_limit(%ebx),%ebx
        subl $3,%ebx
        cmpl %ebx,%ecx
        jae bad_put_user
3:      movl %eax,(%ecx)
        xorl %eax,%eax
        EXIT
ENDPROC(__put_user_4)

ENTRY(__put_user_8)
        ENTER
        movl TI_addr_limit(%ebx),%ebx
        subl $7,%ebx
        cmpl %ebx,%ecx
        jae bad_put_user
4:      movl %eax,(%ecx)
5:      movl %edx,4(%ecx)
        xorl %eax,%eax
        EXIT
ENDPROC(__put_user_8)

bad_put_user:
        CFI_STARTPROC simple
        CFI_DEF_CFA esp, 2*4
        CFI_OFFSET eip, -1*4
        CFI_OFFSET ebx, -2*4
        movl $-14,%eax
        EXIT
END(bad_put_user)

.section __ex_table,"a"
        .long 1b,bad_put_user
        .long 2b,bad_put_user
        .long 3b,bad_put_user
        .long 4b,bad_put_user
        .long 5b,bad_put_user
.previous