1/*
 2 * __put_user functions.
 3 *
 4 * (C) Copyright 2005 Linus Torvalds
 5 * (C) Copyright 2005 Andi Kleen
 6 * (C) Copyright 2008 Glauber Costa
 7 *
 8 * These functions have a non-standard call interface
 9 * to make them more efficient, especially as they
10 * return an error value in addition to the "real"
11 * return value.
12 */
13#include <linux/linkage.h>
14#include <asm/dwarf2.h>
15#include <asm/thread_info.h>
16#include <asm/errno.h>
17#include <asm/asm.h>
 
 
18
19
20/*
21 * __put_user_X
22 *
23 * Inputs:	%eax[:%edx] contains the data
24 *		%ecx contains the address
25 *
26 * Outputs:	%eax is error code (0 or -EFAULT)
27 *
28 * These functions should not modify any other registers,
29 * as they get called from within inline assembly.
30 */
31
32#define ENTER	CFI_STARTPROC ; \
33		GET_THREAD_INFO(%_ASM_BX)
34#define EXIT	ret ; \
35		CFI_ENDPROC
36
37.text
38ENTRY(__put_user_1)
39	ENTER
40	cmp TI_addr_limit(%_ASM_BX),%_ASM_CX
41	jae bad_put_user
 
421:	movb %al,(%_ASM_CX)
43	xor %eax,%eax
44	EXIT
 
45ENDPROC(__put_user_1)
 
46
47ENTRY(__put_user_2)
48	ENTER
49	mov TI_addr_limit(%_ASM_BX),%_ASM_BX
50	sub $1,%_ASM_BX
51	cmp %_ASM_BX,%_ASM_CX
52	jae bad_put_user
 
532:	movw %ax,(%_ASM_CX)
54	xor %eax,%eax
55	EXIT
 
56ENDPROC(__put_user_2)
 
57
58ENTRY(__put_user_4)
59	ENTER
60	mov TI_addr_limit(%_ASM_BX),%_ASM_BX
61	sub $3,%_ASM_BX
62	cmp %_ASM_BX,%_ASM_CX
63	jae bad_put_user
 
643:	movl %eax,(%_ASM_CX)
65	xor %eax,%eax
66	EXIT
 
67ENDPROC(__put_user_4)
 
68
69ENTRY(__put_user_8)
70	ENTER
71	mov TI_addr_limit(%_ASM_BX),%_ASM_BX
72	sub $7,%_ASM_BX
73	cmp %_ASM_BX,%_ASM_CX
74	jae bad_put_user
 
754:	mov %_ASM_AX,(%_ASM_CX)
76#ifdef CONFIG_X86_32
775:	movl %edx,4(%_ASM_CX)
78#endif
79	xor %eax,%eax
80	EXIT
 
81ENDPROC(__put_user_8)
 
82
83bad_put_user:
84	CFI_STARTPROC
 
85	movl $-EFAULT,%eax
86	EXIT
87END(bad_put_user)
88
89	_ASM_EXTABLE(1b,bad_put_user)
90	_ASM_EXTABLE(2b,bad_put_user)
91	_ASM_EXTABLE(3b,bad_put_user)
92	_ASM_EXTABLE(4b,bad_put_user)
93#ifdef CONFIG_X86_32
94	_ASM_EXTABLE(5b,bad_put_user)
95#endif

  1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 * __put_user functions.
  4 *
  5 * (C) Copyright 2005 Linus Torvalds
  6 * (C) Copyright 2005 Andi Kleen
  7 * (C) Copyright 2008 Glauber Costa
  8 *
  9 * These functions have a non-standard call interface
 10 * to make them more efficient, especially as they
 11 * return an error value in addition to the "real"
 12 * return value.
 13 */
 14#include <linux/linkage.h>
 
 15#include <asm/thread_info.h>
 16#include <asm/errno.h>
 17#include <asm/asm.h>
 18#include <asm/smap.h>
 19#include <asm/export.h>
 20
 21
 22/*
 23 * __put_user_X
 24 *
 25 * Inputs:	%eax[:%edx] contains the data
 26 *		%ecx contains the address
 27 *
 28 * Outputs:	%eax is error code (0 or -EFAULT)
 29 *
 30 * These functions should not modify any other registers,
 31 * as they get called from within inline assembly.
 32 */
 33
 34#define ENTER	mov PER_CPU_VAR(current_task), %_ASM_BX
 
 
 
 35
 36.text
 37ENTRY(__put_user_1)
 38	ENTER
 39	cmp TASK_addr_limit(%_ASM_BX),%_ASM_CX
 40	jae .Lbad_put_user
 41	ASM_STAC
 421:	movb %al,(%_ASM_CX)
 43	xor %eax,%eax
 44	ASM_CLAC
 45	ret
 46ENDPROC(__put_user_1)
 47EXPORT_SYMBOL(__put_user_1)
 48
 49ENTRY(__put_user_2)
 50	ENTER
 51	mov TASK_addr_limit(%_ASM_BX),%_ASM_BX
 52	sub $1,%_ASM_BX
 53	cmp %_ASM_BX,%_ASM_CX
 54	jae .Lbad_put_user
 55	ASM_STAC
 562:	movw %ax,(%_ASM_CX)
 57	xor %eax,%eax
 58	ASM_CLAC
 59	ret
 60ENDPROC(__put_user_2)
 61EXPORT_SYMBOL(__put_user_2)
 62
 63ENTRY(__put_user_4)
 64	ENTER
 65	mov TASK_addr_limit(%_ASM_BX),%_ASM_BX
 66	sub $3,%_ASM_BX
 67	cmp %_ASM_BX,%_ASM_CX
 68	jae .Lbad_put_user
 69	ASM_STAC
 703:	movl %eax,(%_ASM_CX)
 71	xor %eax,%eax
 72	ASM_CLAC
 73	ret
 74ENDPROC(__put_user_4)
 75EXPORT_SYMBOL(__put_user_4)
 76
 77ENTRY(__put_user_8)
 78	ENTER
 79	mov TASK_addr_limit(%_ASM_BX),%_ASM_BX
 80	sub $7,%_ASM_BX
 81	cmp %_ASM_BX,%_ASM_CX
 82	jae .Lbad_put_user
 83	ASM_STAC
 844:	mov %_ASM_AX,(%_ASM_CX)
 85#ifdef CONFIG_X86_32
 865:	movl %edx,4(%_ASM_CX)
 87#endif
 88	xor %eax,%eax
 89	ASM_CLAC
 90	RET
 91ENDPROC(__put_user_8)
 92EXPORT_SYMBOL(__put_user_8)
 93
 94.Lbad_put_user_clac:
 95	ASM_CLAC
 96.Lbad_put_user:
 97	movl $-EFAULT,%eax
 98	RET
 
 99
100	_ASM_EXTABLE_UA(1b, .Lbad_put_user_clac)
101	_ASM_EXTABLE_UA(2b, .Lbad_put_user_clac)
102	_ASM_EXTABLE_UA(3b, .Lbad_put_user_clac)
103	_ASM_EXTABLE_UA(4b, .Lbad_put_user_clac)
104#ifdef CONFIG_X86_32
105	_ASM_EXTABLE_UA(5b, .Lbad_put_user_clac)
106#endif