[PATCH] swsusp: low level interface

Introduce the low level interface that can be used for handling the
snapshot of the system memory by the in-kernel swap-writing/reading code of
swsusp and the userland interface code (to be introduced shortly).

Also change the way in which swsusp records the allocated swap pages and,
consequently, simplifies the in-kernel swap-writing/reading code (this is
necessary for the userland interface too).  To this end, it introduces two
helper functions in mm/swapfile.c, so that the swsusp code does not refer
directly to the swap internals.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 4 insertions, 8 deletions

diff --git a/kernel/power/disk.c b/kernel/power/disk.c
index 0b43847dc980..4eb464b71347 100644
--- a/kernel/power/disk.c
+++ b/kernel/power/disk.c
@@ -26,9 +26,9 @@ extern suspend_disk_method_t pm_disk_mode;
 
 extern int swsusp_shrink_memory(void);
 extern int swsusp_suspend(void);
-extern int swsusp_write(struct pbe *pblist, unsigned int nr_pages);
+extern int swsusp_write(void);
 extern int swsusp_check(void);
-extern int swsusp_read(struct pbe **pblist_ptr);
+extern int swsusp_read(void);
 extern void swsusp_close(void);
 extern int swsusp_resume(void);
 
@@ -70,10 +70,6 @@ static void power_down(suspend_disk_method_t mode)
         while(1);
 }
 
-
-static int in_suspend __nosavedata = 0;
-
-
 static inline void platform_finish(void)
 {
         if (pm_disk_mode == PM_DISK_PLATFORM) {
@@ -145,7 +141,7 @@ int pm_suspend_disk(void)
         if (in_suspend) {
                 device_resume();
                 pr_debug("PM: writing image.\n");
-                error = swsusp_write(pagedir_nosave, nr_copy_pages);
+                error = swsusp_write();
                 if (!error)
                         power_down(pm_disk_mode);
                 else {
@@ -216,7 +212,7 @@ static int software_resume(void)
 
         pr_debug("PM: Reading swsusp image.\n");
 
-        if ((error = swsusp_read(&pagedir_nosave))) {
+        if ((error = swsusp_read())) {
                 swsusp_free();
                 goto Thaw;
         }