[PATCH] swsusp: add architecture special saveable pages support
1. Add architecture specific pages save/restore support. Next two patches
will use this to save/restore 'ACPI NVS' pages.
2. Allow reserved pages 'nosave'. This could avoid save/restore BIOS
reserved pages.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Nigel Cunningham <nigel@suspend2.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/suspend.h b/include/linux/suspend.h
index 96e31aa..e82cb10 100644
--- a/include/linux/suspend.h
+++ b/include/linux/suspend.h
@@ -71,6 +71,7 @@
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);
+int swsusp_add_arch_pages(unsigned long start, unsigned long end);
/*
* XXX: We try to keep some more pages free so that I/O operations succeed
diff --git a/kernel/power/power.h b/kernel/power/power.h
index f06f12f..c81f0ed 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -105,6 +105,10 @@
extern unsigned long alloc_swap_page(int swap, struct bitmap_page *bitmap);
extern void free_all_swap_pages(int swap, struct bitmap_page *bitmap);
+extern unsigned int count_special_pages(void);
+extern int save_special_mem(void);
+extern int restore_special_mem(void);
+
extern int swsusp_check(void);
extern int swsusp_shrink_memory(void);
extern void swsusp_free(void);
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 3eeedbb..7f511d8 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -39,6 +39,88 @@
static unsigned int nr_meta_pages;
static unsigned long *buffer;
+struct arch_saveable_page {
+ unsigned long start;
+ unsigned long end;
+ char *data;
+ struct arch_saveable_page *next;
+};
+static struct arch_saveable_page *arch_pages;
+
+int swsusp_add_arch_pages(unsigned long start, unsigned long end)
+{
+ struct arch_saveable_page *tmp;
+
+ while (start < end) {
+ tmp = kzalloc(sizeof(struct arch_saveable_page), GFP_KERNEL);
+ if (!tmp)
+ return -ENOMEM;
+ tmp->start = start;
+ tmp->end = ((start >> PAGE_SHIFT) + 1) << PAGE_SHIFT;
+ if (tmp->end > end)
+ tmp->end = end;
+ tmp->next = arch_pages;
+ start = tmp->end;
+ arch_pages = tmp;
+ }
+ return 0;
+}
+
+static unsigned int count_arch_pages(void)
+{
+ unsigned int count = 0;
+ struct arch_saveable_page *tmp = arch_pages;
+ while (tmp) {
+ count++;
+ tmp = tmp->next;
+ }
+ return count;
+}
+
+static int save_arch_mem(void)
+{
+ char *kaddr;
+ struct arch_saveable_page *tmp = arch_pages;
+ int offset;
+
+ pr_debug("swsusp: Saving arch specific memory");
+ while (tmp) {
+ tmp->data = (char *)__get_free_page(GFP_ATOMIC);
+ if (!tmp->data)
+ return -ENOMEM;
+ offset = tmp->start - (tmp->start & PAGE_MASK);
+ /* arch pages might haven't a 'struct page' */
+ kaddr = kmap_atomic_pfn(tmp->start >> PAGE_SHIFT, KM_USER0);
+ memcpy(tmp->data + offset, kaddr + offset,
+ tmp->end - tmp->start);
+ kunmap_atomic(kaddr, KM_USER0);
+
+ tmp = tmp->next;
+ }
+ return 0;
+}
+
+static int restore_arch_mem(void)
+{
+ char *kaddr;
+ struct arch_saveable_page *tmp = arch_pages;
+ int offset;
+
+ while (tmp) {
+ if (!tmp->data)
+ continue;
+ offset = tmp->start - (tmp->start & PAGE_MASK);
+ kaddr = kmap_atomic_pfn(tmp->start >> PAGE_SHIFT, KM_USER0);
+ memcpy(kaddr + offset, tmp->data + offset,
+ tmp->end - tmp->start);
+ kunmap_atomic(kaddr, KM_USER0);
+ free_page((long)tmp->data);
+ tmp->data = NULL;
+ tmp = tmp->next;
+ }
+ return 0;
+}
+
#ifdef CONFIG_HIGHMEM
unsigned int count_highmem_pages(void)
{
@@ -150,8 +232,35 @@
}
return 0;
}
+#else
+static unsigned int count_highmem_pages(void) {return 0;}
+static int save_highmem(void) {return 0;}
+static int restore_highmem(void) {return 0;}
#endif
+unsigned int count_special_pages(void)
+{
+ return count_arch_pages() + count_highmem_pages();
+}
+
+int save_special_mem(void)
+{
+ int ret;
+ ret = save_arch_mem();
+ if (!ret)
+ ret = save_highmem();
+ return ret;
+}
+
+int restore_special_mem(void)
+{
+ int ret;
+ ret = restore_arch_mem();
+ if (!ret)
+ ret = restore_highmem();
+ return ret;
+}
+
static int pfn_is_nosave(unsigned long pfn)
{
unsigned long nosave_begin_pfn = __pa(&__nosave_begin) >> PAGE_SHIFT;
@@ -177,7 +286,6 @@
return 0;
page = pfn_to_page(pfn);
- BUG_ON(PageReserved(page) && PageNosave(page));
if (PageNosave(page))
return 0;
if (PageReserved(page) && pfn_is_nosave(pfn))
diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c
index f9238fa..78b6e71 100644
--- a/kernel/power/swsusp.c
+++ b/kernel/power/swsusp.c
@@ -62,16 +62,6 @@
int in_suspend __nosavedata = 0;
-#ifdef CONFIG_HIGHMEM
-unsigned int count_highmem_pages(void);
-int save_highmem(void);
-int restore_highmem(void);
-#else
-static int save_highmem(void) { return 0; }
-static int restore_highmem(void) { return 0; }
-static unsigned int count_highmem_pages(void) { return 0; }
-#endif
-
/**
* The following functions are used for tracing the allocated
* swap pages, so that they can be freed in case of an error.
@@ -192,7 +182,7 @@
printk("Shrinking memory... ");
do {
- size = 2 * count_highmem_pages();
+ size = 2 * count_special_pages();
size += size / 50 + count_data_pages();
size += (size + PBES_PER_PAGE - 1) / PBES_PER_PAGE +
PAGES_FOR_IO;
@@ -234,7 +224,7 @@
goto Enable_irqs;
}
- if ((error = save_highmem())) {
+ if ((error = save_special_mem())) {
printk(KERN_ERR "swsusp: Not enough free pages for highmem\n");
goto Restore_highmem;
}
@@ -245,7 +235,7 @@
/* Restore control flow magically appears here */
restore_processor_state();
Restore_highmem:
- restore_highmem();
+ restore_special_mem();
device_power_up();
Enable_irqs:
local_irq_enable();
@@ -271,7 +261,7 @@
*/
swsusp_free();
restore_processor_state();
- restore_highmem();
+ restore_special_mem();
touch_softlockup_watchdog();
device_power_up();
local_irq_enable();