linux-stable/include/linux/suspend.h
Rafael J. Wysocki 940864ddab [PATCH] swsusp: Use memory bitmaps during resume
Make swsusp use memory bitmaps to store its internal information during the
resume phase of the suspend-resume cycle.

If the pfns of saveable pages are saved during the suspend phase instead of
the kernel virtual addresses of these pages, we can use them during the resume
phase directly to set the corresponding bits in a memory bitmap.  Then, this
bitmap is used to mark the page frames corresponding to the pages that were
saveable before the suspend (aka "unsafe" page frames).

Next, we allocate as many page frames as needed to store the entire suspend
image and make sure that there will be some extra free "safe" page frames for
the list of PBEs constructed later.  Subsequently, the image is loaded and, if
possible, the data loaded from it are written into their "original" page
frames (ie.  the ones they had occupied before the suspend).

The image data that cannot be written into their "original" page frames are
loaded into "safe" page frames and their "original" kernel virtual addresses,
as well as the addresses of the "safe" pages containing their copies, are
stored in a list of PBEs.  Finally, the list of PBEs is used to copy the
remaining image data into their "original" page frames (this is done
atomically, by the architecture-dependent parts of swsusp).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:49:02 -07:00

55 lines
1.4 KiB
C

#ifndef _LINUX_SWSUSP_H
#define _LINUX_SWSUSP_H
#if defined(CONFIG_X86) || defined(CONFIG_FRV) || defined(CONFIG_PPC32)
#include <asm/suspend.h>
#endif
#include <linux/swap.h>
#include <linux/notifier.h>
#include <linux/init.h>
#include <linux/pm.h>
/* page backup entry */
struct pbe {
unsigned long address; /* address of the copy */
unsigned long orig_address; /* original address of page */
struct pbe *next;
};
/* mm/page_alloc.c */
extern void drain_local_pages(void);
extern void mark_free_pages(struct zone *zone);
#ifdef CONFIG_PM
/* kernel/power/swsusp.c */
extern int software_suspend(void);
#if defined(CONFIG_VT) && defined(CONFIG_VT_CONSOLE)
extern int pm_prepare_console(void);
extern void pm_restore_console(void);
#else
static inline int pm_prepare_console(void) { return 0; }
static inline void pm_restore_console(void) {}
#endif /* defined(CONFIG_VT) && defined(CONFIG_VT_CONSOLE) */
#else
static inline int software_suspend(void)
{
printk("Warning: fake suspend called\n");
return -ENOSYS;
}
#endif /* CONFIG_PM */
void save_processor_state(void);
void restore_processor_state(void);
struct saved_context;
void __save_processor_state(struct saved_context *ctxt);
void __restore_processor_state(struct saved_context *ctxt);
unsigned long get_safe_page(gfp_t gfp_mask);
/*
* XXX: We try to keep some more pages free so that I/O operations succeed
* without paging. Might this be more?
*/
#define PAGES_FOR_IO 1024
#endif /* _LINUX_SWSUSP_H */