79 lines
1.9 KiB
C
79 lines
1.9 KiB
C
|
/*
|
||
|
|
* This program is free software; you can redistribute it and/or modify
|
||
|
|
* it under the terms of the GNU General Public License as published by
|
||
|
|
* the Free Software Foundation; either version 2 of the License, or
|
||
|
|
* (at your option) any later version.
|
||
|
|
*
|
||
|
|
* This program is distributed in the hope that it will be useful,
|
||
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
|
|
* GNU General Public License for more details.
|
||
|
|
*
|
||
|
|
* You should have received a copy of the GNU General Public License
|
||
|
|
* along with this program; if not, write to the Free Software
|
||
|
|
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
|
||
|
|
*
|
||
|
|
* Copyright (C) IBM Corporation, 2011
|
||
|
|
*
|
||
|
|
* Authors: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
|
||
|
|
* Anton Blanchard <anton@au.ibm.com>
|
||
|
|
*/
|
||
|
|
#include <linux/uaccess.h>
|
||
|
|
#include <linux/hardirq.h>
|
||
|
|
#include <asm/switch_to.h>
|
||
|
|
#include <asm/asm-prototypes.h>
|
||
|
|
|
||
|
|
int enter_vmx_usercopy(void)
|
||
|
|
{
|
||
|
|
if (in_interrupt())
|
||
|
|
return 0;
|
||
|
|
|
||
|
|
preempt_disable();
|
||
|
|
/*
|
||
|
|
* We need to disable page faults as they can call schedule and
|
||
|
|
* thus make us lose the VMX context. So on page faults, we just
|
||
|
|
* fail which will cause a fallback to the normal non-vmx copy.
|
||
|
|
*/
|
||
|
|
pagefault_disable();
|
||
|
|
|
||
|
|
enable_kernel_altivec();
|
||
|
|
|
||
|
|
return 1;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* This function must return 0 because we tail call optimise when calling
|
||
|
|
* from __copy_tofrom_user_power7 which returns 0 on success.
|
||
|
|
*/
|
||
|
|
int exit_vmx_usercopy(void)
|
||
|
|
{
|
||
|
|
disable_kernel_altivec();
|
||
|
|
pagefault_enable();
|
||
|
|
preempt_enable();
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
int enter_vmx_ops(void)
|
||
|
|
{
|
||
|
|
if (in_interrupt())
|
||
|
|
return 0;
|
||
|
|
|
||
|
|
preempt_disable();
|
||
|
|
|
||
|
|
enable_kernel_altivec();
|
||
|
|
|
||
|
|
return 1;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* All calls to this function will be optimised into tail calls. We are
|
||
|
|
* passed a pointer to the destination which we return as required by a
|
||
|
|
* memcpy implementation.
|
||
|
|
*/
|
||
|
|
void *exit_vmx_ops(void *dest)
|
||
|
|
{
|
||
|
|
disable_kernel_altivec();
|
||
|
|
preempt_enable();
|
||
|
|
return dest;
|
||
|
|
}
|