| /* |
| * 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> |
| |
| int enter_vmx_copy(void) |
| { |
| if (in_interrupt()) |
| return 0; |
| |
| /* This acts as preempt_disable() as well and will make |
| * enable_kernel_altivec(). 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_copy(void) |
| { |
| pagefault_enable(); |
| return 0; |
| } |