/*
* __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 ; \
GET_THREAD_INFO(%ebx)
#define EXIT ret ; \
CFI_ENDPROC
.text
ENTRY(__put_user_1)
ENTER
cmp TI_addr_limit(%ebx),%ecx
jae bad_put_user
1: movb %al,(%ecx)
xor %eax,%eax
EXIT
ENDPROC(__put_user_1)
ENTRY(__put_user_2)
ENTER
mov TI_addr_limit(%ebx),%ebx
sub $1,%ebx
cmp %ebx,%ecx
jae bad_put_user
2: movw %ax,(%ecx)
xor %eax,%eax
EXIT
ENDPROC(__put_user_2)
ENTRY(__put_user_4)
ENTER
mov TI_addr_limit(%ebx),%ebx
sub $3,%ebx
cmp %ebx,%ecx
jae bad_put_user
3: movl %eax,(%ecx)
xor %eax,%eax
EXIT
ENDPROC(__put_user_4)
ENTRY(__put_user_8)
ENTER
mov TI_addr_limit(%ebx),%ebx
sub $7,%ebx
cmp %ebx,%ecx
jae bad_put_user
4: movl %eax,(%ecx)
5: movl %edx,4(%ecx)
xor %eax,%eax
EXIT
ENDPROC(__put_user_8)
bad_put_user:
CFI_STARTPROC
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
