1/*
 2 * This program is free software; you can redistribute it and/or modify
 3 * it under the terms of the GNU General Public License as published by
 4 * the Free Software Foundation; either version 2 of the License, or
 5 * (at your option) any later version.
 6 *
 7 * This program is distributed in the hope that it will be useful,
 8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10 * GNU General Public License for more details.
11 *
12 * You should have received a copy of the GNU General Public License
13 * along with this program; if not, write to the Free Software
14 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
15 *
16 * Copyright (C) IBM Corporation, 2011
17 *
18 * Authors: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
19 *          Anton Blanchard <anton@au.ibm.com>
20 */
21#include <linux/uaccess.h>
22#include <linux/hardirq.h>
23#include <asm/switch_to.h>
24#include <asm/asm-prototypes.h>
25
26int enter_vmx_usercopy(void)
27{
28	if (in_interrupt())
29		return 0;
30
31	preempt_disable();
32	/*
33	 * We need to disable page faults as they can call schedule and
34	 * thus make us lose the VMX context. So on page faults, we just
35	 * fail which will cause a fallback to the normal non-vmx copy.
36	 */
37	pagefault_disable();
38
39	enable_kernel_altivec();
40
41	return 1;
42}
43
44/*
45 * This function must return 0 because we tail call optimise when calling
46 * from __copy_tofrom_user_power7 which returns 0 on success.
47 */
48int exit_vmx_usercopy(void)
49{
50	disable_kernel_altivec();
51	pagefault_enable();
52	preempt_enable();
53	return 0;
54}
55
56int enter_vmx_copy(void)
57{
58	if (in_interrupt())
59		return 0;
60
61	preempt_disable();
62
63	enable_kernel_altivec();
64
65	return 1;
66}
67
68/*
69 * All calls to this function will be optimised into tail calls. We are
70 * passed a pointer to the destination which we return as required by a
71 * memcpy implementation.
72 */
73void *exit_vmx_copy(void *dest)
74{
75	disable_kernel_altivec();
76	preempt_enable();
77	return dest;
78}

 1// SPDX-License-Identifier: GPL-2.0-or-later
 2/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 3 *
 4 * Copyright (C) IBM Corporation, 2011
 5 *
 6 * Authors: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
 7 *          Anton Blanchard <anton@au.ibm.com>
 8 */
 9#include <linux/uaccess.h>
10#include <linux/hardirq.h>
11#include <asm/switch_to.h>
12#include <asm/asm-prototypes.h>
13
14int enter_vmx_usercopy(void)
15{
16	if (in_interrupt())
17		return 0;
18
19	preempt_disable();
20	/*
21	 * We need to disable page faults as they can call schedule and
22	 * thus make us lose the VMX context. So on page faults, we just
23	 * fail which will cause a fallback to the normal non-vmx copy.
24	 */
25	pagefault_disable();
26
27	enable_kernel_altivec();
28
29	return 1;
30}
31
32/*
33 * This function must return 0 because we tail call optimise when calling
34 * from __copy_tofrom_user_power7 which returns 0 on success.
35 */
36int exit_vmx_usercopy(void)
37{
38	disable_kernel_altivec();
39	pagefault_enable();
40	preempt_enable();
41	return 0;
42}
43
44int enter_vmx_ops(void)
45{
46	if (in_interrupt())
47		return 0;
48
49	preempt_disable();
50
51	enable_kernel_altivec();
52
53	return 1;
54}
55
56/*
57 * All calls to this function will be optimised into tail calls. We are
58 * passed a pointer to the destination which we return as required by a
59 * memcpy implementation.
60 */
61void *exit_vmx_ops(void *dest)
62{
63	disable_kernel_altivec();
64	preempt_enable();
65	return dest;
66}