 ae3a197e3d
			
		
	
	
	ae3a197e3d
	
	
	
		
			
			Disintegrate asm/system.h for PowerPC. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> cc: linuxppc-dev@lists.ozlabs.org
		
			
				
	
	
		
			51 lines
		
	
	
	
		
			1.5 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			51 lines
		
	
	
	
		
			1.5 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * This program is free software; you can redistribute it and/or modify
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|  * it under the terms of the GNU General Public License as published by
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|  * the Free Software Foundation; either version 2 of the License, or
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|  * (at your option) any later version.
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|  *
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|  * This program is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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|  * GNU General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU General Public License
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|  * along with this program; if not, write to the Free Software
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|  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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|  *
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|  * Copyright (C) IBM Corporation, 2011
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|  *
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|  * Authors: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
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|  *          Anton Blanchard <anton@au.ibm.com>
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|  */
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| #include <linux/uaccess.h>
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| #include <linux/hardirq.h>
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| #include <asm/switch_to.h>
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| 
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| int enter_vmx_copy(void)
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| {
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| 	if (in_interrupt())
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| 		return 0;
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| 
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| 	/* This acts as preempt_disable() as well and will make
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| 	 * enable_kernel_altivec(). We need to disable page faults
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| 	 * as they can call schedule and thus make us lose the VMX
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| 	 * context. So on page faults, we just fail which will cause
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| 	 * a fallback to the normal non-vmx copy.
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| 	 */
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| 	pagefault_disable();
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| 
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| 	enable_kernel_altivec();
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| 
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| 	return 1;
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| }
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| 
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| /*
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|  * This function must return 0 because we tail call optimise when calling
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|  * from __copy_tofrom_user_power7 which returns 0 on success.
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|  */
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| int exit_vmx_copy(void)
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| {
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| 	pagefault_enable();
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| 	return 0;
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| }
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