linux/arch/powerpc/kernel/suspend.c

/*
 * Suspend support specific for power.
 *
 * Distribute under GPLv2
 *
 * Copyright (c) 2002 Pavel Machek <pavel@ucw.cz>
 * Copyright (c) 2001 Patrick Mochel <mochel@osdl.org>
 */

#include <linux/mm.h>
#include <asm/page.h>

/* References to section boundaries */
extern const void __nosave_begin, __nosave_end;

/*
 *	pfn_is_nosave - check if given pfn is in the 'nosave' section
 */

int pfn_is_nosave(unsigned long pfn)
{
	unsigned long nosave_begin_pfn = __pa(&__nosave_begin) >> PAGE_SHIFT;
	unsigned long nosave_end_pfn = PAGE_ALIGN(__pa(&__nosave_end)) >> PAGE_SHIFT;
	return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);
}
[PATCH] x86: Move swsusp __pa() dependent code to arch portion o __pa() should be used only on kernel linearly mapped virtual addresses and not on kernel text and data addresses. o Hibernation code needs to determine the physical address associated with kernel symbol to mark a section boundary which contains pages which don't have to be saved and restored during hibernate/resume operation. o Move this piece of code in arch dependent section. So that architectures which don't have kernel text/data mapped into kernel linearly mapped region can come up with their own ways of determining physical addresses associated with a kernel text. Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com> Signed-off-by: Andi Kleen <ak@suse.de> 2007-05-02 17:27:07 +00:00			`/*`
			`* Suspend support specific for power.`
			`*`
			`* Distribute under GPLv2`
			`*`
update email address pavel@suse.cz no longer works, replace it with working address. Signed-off-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Jiri Kosina <jkosina@suse.cz> 2010-07-18 12:27:13 +00:00			`* Copyright (c) 2002 Pavel Machek <pavel@ucw.cz>`
[PATCH] x86: Move swsusp __pa() dependent code to arch portion o __pa() should be used only on kernel linearly mapped virtual addresses and not on kernel text and data addresses. o Hibernation code needs to determine the physical address associated with kernel symbol to mark a section boundary which contains pages which don't have to be saved and restored during hibernate/resume operation. o Move this piece of code in arch dependent section. So that architectures which don't have kernel text/data mapped into kernel linearly mapped region can come up with their own ways of determining physical addresses associated with a kernel text. Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com> Signed-off-by: Andi Kleen <ak@suse.de> 2007-05-02 17:27:07 +00:00			`* Copyright (c) 2001 Patrick Mochel <mochel@osdl.org>`
			`*/`

PAGE_ALIGN(): correctly handle 64-bit values on 32-bit architectures On 32-bit architectures PAGE_ALIGN() truncates 64-bit values to the 32-bit boundary. For example: u64 val = PAGE_ALIGN(size); always returns a value < 4GB even if size is greater than 4GB. The problem resides in PAGE_MASK definition (from include/asm-x86/page.h for example): #define PAGE_SHIFT 12 #define PAGE_SIZE (_AC(1,UL) << PAGE_SHIFT) #define PAGE_MASK (~(PAGE_SIZE-1)) ... #define PAGE_ALIGN(addr) (((addr)+PAGE_SIZE-1)&PAGE_MASK) The "~" is performed on a 32-bit value, so everything in "and" with PAGE_MASK greater than 4GB will be truncated to the 32-bit boundary. Using the ALIGN() macro seems to be the right way, because it uses typeof(addr) for the mask. Also move the PAGE_ALIGN() definitions out of include/asm-*/page.h in include/linux/mm.h. See also lkml discussion: http://lkml.org/lkml/2008/6/11/237 [akpm@linux-foundation.org: fix drivers/media/video/uvc/uvc_queue.c] [akpm@linux-foundation.org: fix v850] [akpm@linux-foundation.org: fix powerpc] [akpm@linux-foundation.org: fix arm] [akpm@linux-foundation.org: fix mips] [akpm@linux-foundation.org: fix drivers/media/video/pvrusb2/pvrusb2-dvb.c] [akpm@linux-foundation.org: fix drivers/mtd/maps/uclinux.c] [akpm@linux-foundation.org: fix powerpc] Signed-off-by: Andrea Righi <righi.andrea@gmail.com> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 2008-07-24 04:28:13 +00:00			`#include <linux/mm.h>`
[PATCH] x86: Move swsusp __pa() dependent code to arch portion o __pa() should be used only on kernel linearly mapped virtual addresses and not on kernel text and data addresses. o Hibernation code needs to determine the physical address associated with kernel symbol to mark a section boundary which contains pages which don't have to be saved and restored during hibernate/resume operation. o Move this piece of code in arch dependent section. So that architectures which don't have kernel text/data mapped into kernel linearly mapped region can come up with their own ways of determining physical addresses associated with a kernel text. Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com> Signed-off-by: Andi Kleen <ak@suse.de> 2007-05-02 17:27:07 +00:00			`#include <asm/page.h>`

			`/* References to section boundaries */`
			`extern const void __nosave_begin, __nosave_end;`

			`/*`
			`* pfn_is_nosave - check if given pfn is in the 'nosave' section`
			`*/`

			`int pfn_is_nosave(unsigned long pfn)`
			`{`
			`unsigned long nosave_begin_pfn = __pa(&__nosave_begin) >> PAGE_SHIFT;`
			`unsigned long nosave_end_pfn = PAGE_ALIGN(__pa(&__nosave_end)) >> PAGE_SHIFT;`
			`return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);`
			`}`