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)
+static unsigned int count_highmem_pages(void)
{
struct zone *zone;
unsigned long zone_pfn;
return 0;
}
-int save_highmem(void)
+static int save_highmem(void)
{
struct zone *zone;
int res = 0;
pr_debug("swsusp: Saving Highmem");
+ drain_local_pages();
for_each_zone (zone) {
if (is_highmem(zone))
res = save_highmem_zone(zone);
return 0;
}
-int restore_highmem(void)
+static int restore_highmem(void)
{
printk("swsusp: Restoring Highmem\n");
while (highmem_copy) {
}
return 0;
}
+#else
+static inline unsigned int count_highmem_pages(void) {return 0;}
+static inline int save_highmem(void) {return 0;}
+static inline 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;
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))
* free_pagedir - free pages allocated with alloc_pagedir()
*/
-static void free_pagedir(struct pbe *pblist)
+static void free_pagedir(struct pbe *pblist, int clear_nosave_free)
{
struct pbe *pbe;
while (pblist) {
pbe = (pblist + PB_PAGE_SKIP)->next;
ClearPageNosave(virt_to_page(pblist));
- ClearPageNosaveFree(virt_to_page(pblist));
+ if (clear_nosave_free)
+ ClearPageNosaveFree(virt_to_page(pblist));
free_page((unsigned long)pblist);
pblist = pbe;
}
}
}
-/**
- * On resume it is necessary to trace and eventually free the unsafe
- * pages that have been allocated, because they are needed for I/O
- * (on x86-64 we likely will "eat" these pages once again while
- * creating the temporary page translation tables)
- */
-
-struct eaten_page {
- struct eaten_page *next;
- char padding[PAGE_SIZE - sizeof(void *)];
-};
-
-static struct eaten_page *eaten_pages = NULL;
-
-static void release_eaten_pages(void)
-{
- struct eaten_page *p, *q;
-
- p = eaten_pages;
- while (p) {
- q = p->next;
- /* We don't want swsusp_free() to free this page again */
- ClearPageNosave(virt_to_page(p));
- free_page((unsigned long)p);
- p = q;
- }
- eaten_pages = NULL;
-}
+static unsigned int unsafe_pages;
/**
* @safe_needed - on resume, for storing the PBE list and the image,
* we can only use memory pages that do not conflict with the pages
- * which had been used before suspend.
+ * used before suspend.
*
* The unsafe pages are marked with the PG_nosave_free flag
- *
- * Allocated but unusable (ie eaten) memory pages should be marked
- * so that swsusp_free() can release them
+ * and we count them using unsafe_pages
*/
static inline void *alloc_image_page(gfp_t gfp_mask, int safe_needed)
{
void *res;
+ res = (void *)get_zeroed_page(gfp_mask);
if (safe_needed)
- do {
+ while (res && PageNosaveFree(virt_to_page(res))) {
+ /* The page is unsafe, mark it for swsusp_free() */
+ SetPageNosave(virt_to_page(res));
+ unsafe_pages++;
res = (void *)get_zeroed_page(gfp_mask);
- if (res && PageNosaveFree(virt_to_page(res))) {
- /* This is for swsusp_free() */
- SetPageNosave(virt_to_page(res));
- ((struct eaten_page *)res)->next = eaten_pages;
- eaten_pages = res;
- }
- } while (res && PageNosaveFree(virt_to_page(res)));
- else
- res = (void *)get_zeroed_page(gfp_mask);
+ }
if (res) {
SetPageNosave(virt_to_page(res));
SetPageNosaveFree(virt_to_page(res));
* On each page we set up a list of struct_pbe elements.
*/
-struct pbe *alloc_pagedir(unsigned int nr_pages, gfp_t gfp_mask, int safe_needed)
+static struct pbe *alloc_pagedir(unsigned int nr_pages, gfp_t gfp_mask,
+ int safe_needed)
{
unsigned int num;
struct pbe *pblist, *pbe;
pbe->next = alloc_image_page(gfp_mask, safe_needed);
}
if (!pbe) { /* get_zeroed_page() failed */
- free_pagedir(pblist);
+ free_pagedir(pblist, 1);
pblist = NULL;
} else
create_pbe_list(pblist, nr_pages);
return -EFAULT;
}
+ unsafe_pages = 0;
+
return 0;
}
}
/**
- * create_image - use metadata contained in the PBE list
+ * prepare_image - use metadata contained in the PBE list
* pointed to by pagedir_nosave to mark the pages that will
* be overwritten in the process of restoring the system
- * memory state from the image and allocate memory for
- * the image avoiding these pages
+ * memory state from the image ("unsafe" pages) and allocate
+ * memory for the image
+ *
+ * The idea is to allocate the PBE list first and then
+ * allocate as many pages as it's needed for the image data,
+ * but not to assign these pages to the PBEs initially.
+ * Instead, we just mark them as allocated and create a list
+ * of "safe" which will be used later
*/
-static int create_image(struct snapshot_handle *handle)
+struct safe_page {
+ struct safe_page *next;
+ char padding[PAGE_SIZE - sizeof(void *)];
+};
+
+static struct safe_page *safe_pages;
+
+static int prepare_image(struct snapshot_handle *handle)
{
int error = 0;
- struct pbe *p, *pblist;
+ unsigned int nr_pages = nr_copy_pages;
+ struct pbe *p, *pblist = NULL;
p = pagedir_nosave;
error = mark_unsafe_pages(p);
if (!error) {
- pblist = alloc_pagedir(nr_copy_pages, GFP_ATOMIC, 1);
+ pblist = alloc_pagedir(nr_pages, GFP_ATOMIC, 1);
if (pblist)
copy_page_backup_list(pblist, p);
- free_pagedir(p);
+ free_pagedir(p, 0);
if (!pblist)
error = -ENOMEM;
}
- if (!error)
- error = alloc_data_pages(pblist, GFP_ATOMIC, 1);
+ safe_pages = NULL;
+ if (!error && nr_pages > unsafe_pages) {
+ nr_pages -= unsafe_pages;
+ while (nr_pages--) {
+ struct safe_page *ptr;
+
+ ptr = (struct safe_page *)get_zeroed_page(GFP_ATOMIC);
+ if (!ptr) {
+ error = -ENOMEM;
+ break;
+ }
+ if (!PageNosaveFree(virt_to_page(ptr))) {
+ /* The page is "safe", add it to the list */
+ ptr->next = safe_pages;
+ safe_pages = ptr;
+ }
+ /* Mark the page as allocated */
+ SetPageNosave(virt_to_page(ptr));
+ SetPageNosaveFree(virt_to_page(ptr));
+ }
+ }
if (!error) {
- release_eaten_pages();
pagedir_nosave = pblist;
} else {
- pagedir_nosave = NULL;
handle->pbe = NULL;
- nr_copy_pages = 0;
- nr_meta_pages = 0;
+ swsusp_free();
}
return error;
}
+static void *get_buffer(struct snapshot_handle *handle)
+{
+ struct pbe *pbe = handle->pbe, *last = handle->last_pbe;
+ struct page *page = virt_to_page(pbe->orig_address);
+
+ if (PageNosave(page) && PageNosaveFree(page)) {
+ /*
+ * We have allocated the "original" page frame and we can
+ * use it directly to store the read page
+ */
+ pbe->address = 0;
+ if (last && last->next)
+ last->next = NULL;
+ return (void *)pbe->orig_address;
+ }
+ /*
+ * The "original" page frame has not been allocated and we have to
+ * use a "safe" page frame to store the read page
+ */
+ pbe->address = (unsigned long)safe_pages;
+ safe_pages = safe_pages->next;
+ if (last)
+ last->next = pbe;
+ handle->last_pbe = pbe;
+ return (void *)pbe->address;
+}
+
/**
* snapshot_write_next - used for writing the system memory snapshot.
*
} else if (handle->prev <= nr_meta_pages) {
handle->pbe = unpack_orig_addresses(buffer, handle->pbe);
if (!handle->pbe) {
- error = create_image(handle);
+ error = prepare_image(handle);
if (error)
return error;
handle->pbe = pagedir_nosave;
- handle->buffer = (void *)handle->pbe->address;
+ handle->last_pbe = NULL;
+ handle->buffer = get_buffer(handle);
}
} else {
handle->pbe = handle->pbe->next;
- handle->buffer = (void *)handle->pbe->address;
+ handle->buffer = get_buffer(handle);
}
handle->prev = handle->page;
}
projects / linux-2.6 / blobdiff