]> Pileus Git - ~andy/linux/blobdiff - kernel/power/snapshot.c
[PATCH] Change the name of pagedir_nosave
[~andy/linux] / kernel / power / snapshot.c
index 3d9284100b22105e5323adf37c3ab4aff46e4391..1d276b3ae15292df2e92c64de9069c8a13975b14 100644 (file)
 
 #include "power.h"
 
-struct pbe *pagedir_nosave;
+/* List of PBEs used for creating and restoring the suspend image */
+struct pbe *restore_pblist;
+
 static unsigned int nr_copy_pages;
 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
-static unsigned int count_highmem_pages(void)
+unsigned int count_highmem_pages(void)
 {
        struct zone *zone;
        unsigned long zone_pfn;
@@ -199,7 +119,7 @@ static int save_highmem_zone(struct zone *zone)
        return 0;
 }
 
-static int save_highmem(void)
+int save_highmem(void)
 {
        struct zone *zone;
        int res = 0;
@@ -216,7 +136,7 @@ static int save_highmem(void)
        return 0;
 }
 
-static int restore_highmem(void)
+int restore_highmem(void)
 {
        printk("swsusp: Restoring Highmem\n");
        while (highmem_copy) {
@@ -238,30 +158,59 @@ static inline int save_highmem(void) {return 0;}
 static inline int restore_highmem(void) {return 0;}
 #endif
 
-unsigned int count_special_pages(void)
+/**
+ *     @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
+ *     used before suspend.
+ *
+ *     The unsafe pages are marked with the PG_nosave_free flag
+ *     and we count them using unsafe_pages
+ */
+
+static unsigned int unsafe_pages;
+
+static void *alloc_image_page(gfp_t gfp_mask, int safe_needed)
 {
-       return count_arch_pages() + count_highmem_pages();
+       void *res;
+
+       res = (void *)get_zeroed_page(gfp_mask);
+       if (safe_needed)
+               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) {
+               SetPageNosave(virt_to_page(res));
+               SetPageNosaveFree(virt_to_page(res));
+       }
+       return res;
 }
 
-int save_special_mem(void)
+unsigned long get_safe_page(gfp_t gfp_mask)
 {
-       int ret;
-       ret = save_arch_mem();
-       if (!ret)
-               ret = save_highmem();
-       return ret;
+       return (unsigned long)alloc_image_page(gfp_mask, 1);
 }
 
-int restore_special_mem(void)
+/**
+ *     free_image_page - free page represented by @addr, allocated with
+ *     alloc_image_page (page flags set by it must be cleared)
+ */
+
+static inline void free_image_page(void *addr, int clear_nosave_free)
 {
-       int ret;
-       ret = restore_arch_mem();
-       if (!ret)
-               ret = restore_highmem();
-       return ret;
+       ClearPageNosave(virt_to_page(addr));
+       if (clear_nosave_free)
+               ClearPageNosaveFree(virt_to_page(addr));
+       free_page((unsigned long)addr);
 }
 
-static int pfn_is_nosave(unsigned long pfn)
+/**
+ *     pfn_is_nosave - check if given pfn is in the 'nosave' section
+ */
+
+static inline 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;
@@ -272,70 +221,77 @@ static int pfn_is_nosave(unsigned long pfn)
  *     saveable - Determine whether a page should be cloned or not.
  *     @pfn:   The page
  *
- *     We save a page if it's Reserved, and not in the range of pages
- *     statically defined as 'unsaveable', or if it isn't reserved, and
- *     isn't part of a free chunk of pages.
+ *     We save a page if it isn't Nosave, and is not in the range of pages
+ *     statically defined as 'unsaveable', and it
+ *     isn't part of a free chunk of pages.
  */
 
-static int saveable(struct zone *zone, unsigned long *zone_pfn)
+static struct page *saveable_page(unsigned long pfn)
 {
-       unsigned long pfn = *zone_pfn + zone->zone_start_pfn;
        struct page *page;
 
        if (!pfn_valid(pfn))
-               return 0;
+               return NULL;
 
        page = pfn_to_page(pfn);
+
        if (PageNosave(page))
-               return 0;
+               return NULL;
        if (PageReserved(page) && pfn_is_nosave(pfn))
-               return 0;
+               return NULL;
        if (PageNosaveFree(page))
-               return 0;
+               return NULL;
 
-       return 1;
+       return page;
 }
 
 unsigned int count_data_pages(void)
 {
        struct zone *zone;
-       unsigned long zone_pfn;
+       unsigned long pfn, max_zone_pfn;
        unsigned int n = 0;
 
        for_each_zone (zone) {
                if (is_highmem(zone))
                        continue;
                mark_free_pages(zone);
-               for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn)
-                       n += saveable(zone, &zone_pfn);
+               max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
+               for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
+                       n += !!saveable_page(pfn);
        }
        return n;
 }
 
+static inline void copy_data_page(long *dst, long *src)
+{
+       int n;
+
+       /* copy_page and memcpy are not usable for copying task structs. */
+       for (n = PAGE_SIZE / sizeof(long); n; n--)
+               *dst++ = *src++;
+}
+
 static void copy_data_pages(struct pbe *pblist)
 {
        struct zone *zone;
-       unsigned long zone_pfn;
-       struct pbe *pbe, *p;
+       unsigned long pfn, max_zone_pfn;
+       struct pbe *pbe;
 
        pbe = pblist;
        for_each_zone (zone) {
                if (is_highmem(zone))
                        continue;
                mark_free_pages(zone);
-               /* This is necessary for swsusp_free() */
-               for_each_pb_page (p, pblist)
-                       SetPageNosaveFree(virt_to_page(p));
-               for_each_pbe (p, pblist)
-                       SetPageNosaveFree(virt_to_page(p->address));
-               for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) {
-                       if (saveable(zone, &zone_pfn)) {
-                               struct page *page;
-                               page = pfn_to_page(zone_pfn + zone->zone_start_pfn);
+               max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
+               for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) {
+                       struct page *page = saveable_page(pfn);
+
+                       if (page) {
+                               void *ptr = page_address(page);
+
                                BUG_ON(!pbe);
-                               pbe->orig_address = (unsigned long)page_address(page);
-                               /* copy_page is not usable for copying task structs. */
-                               memcpy((void *)pbe->address, (void *)pbe->orig_address, PAGE_SIZE);
+                               copy_data_page((void *)pbe->address, ptr);
+                               pbe->orig_address = (unsigned long)ptr;
                                pbe = pbe->next;
                        }
                }
@@ -343,7 +299,6 @@ static void copy_data_pages(struct pbe *pblist)
        BUG_ON(pbe);
 }
 
-
 /**
  *     free_pagedir - free pages allocated with alloc_pagedir()
  */
@@ -354,10 +309,7 @@ static void free_pagedir(struct pbe *pblist, int clear_nosave_free)
 
        while (pblist) {
                pbe = (pblist + PB_PAGE_SKIP)->next;
-               ClearPageNosave(virt_to_page(pblist));
-               if (clear_nosave_free)
-                       ClearPageNosaveFree(virt_to_page(pblist));
-               free_page((unsigned long)pblist);
+               free_image_page(pblist, clear_nosave_free);
                pblist = pbe;
        }
 }
@@ -366,12 +318,12 @@ static void free_pagedir(struct pbe *pblist, int clear_nosave_free)
  *     fill_pb_page - Create a list of PBEs on a given memory page
  */
 
-static inline void fill_pb_page(struct pbe *pbpage)
+static inline void fill_pb_page(struct pbe *pbpage, unsigned int n)
 {
        struct pbe *p;
 
        p = pbpage;
-       pbpage += PB_PAGE_SKIP;
+       pbpage += n - 1;
        do
                p->next = p + 1;
        while (++p < pbpage);
@@ -380,60 +332,27 @@ static inline void fill_pb_page(struct pbe *pbpage)
 /**
  *     create_pbe_list - Create a list of PBEs on top of a given chain
  *     of memory pages allocated with alloc_pagedir()
+ *
+ *     This function assumes that pages allocated by alloc_image_page() will
+ *     always be zeroed.
  */
 
 static inline void create_pbe_list(struct pbe *pblist, unsigned int nr_pages)
 {
-       struct pbe *pbpage, *p;
+       struct pbe *pbpage;
        unsigned int num = PBES_PER_PAGE;
 
        for_each_pb_page (pbpage, pblist) {
                if (num >= nr_pages)
                        break;
 
-               fill_pb_page(pbpage);
+               fill_pb_page(pbpage, PBES_PER_PAGE);
                num += PBES_PER_PAGE;
        }
        if (pbpage) {
-               for (num -= PBES_PER_PAGE - 1, p = pbpage; num < nr_pages; p++, num++)
-                       p->next = p + 1;
-               p->next = 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
- *     used before suspend.
- *
- *     The unsafe pages are marked with the PG_nosave_free flag
- *     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)
-               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) {
-               SetPageNosave(virt_to_page(res));
-               SetPageNosaveFree(virt_to_page(res));
+               num -= PBES_PER_PAGE;
+               fill_pb_page(pbpage, nr_pages - num);
        }
-       return res;
-}
-
-unsigned long get_safe_page(gfp_t gfp_mask)
-{
-       return (unsigned long)alloc_image_page(gfp_mask, 1);
 }
 
 /**
@@ -459,17 +378,17 @@ static struct pbe *alloc_pagedir(unsigned int nr_pages, gfp_t gfp_mask,
                return NULL;
 
        pblist = alloc_image_page(gfp_mask, safe_needed);
-       /* FIXME: rewrite this ugly loop */
-       for (pbe = pblist, num = PBES_PER_PAGE; pbe && num < nr_pages;
-                       pbe = pbe->next, num += PBES_PER_PAGE) {
+       pbe = pblist;
+       for (num = PBES_PER_PAGE; num < nr_pages; num += PBES_PER_PAGE) {
+               if (!pbe) {
+                       free_pagedir(pblist, 1);
+                       return NULL;
+               }
                pbe += PB_PAGE_SKIP;
                pbe->next = alloc_image_page(gfp_mask, safe_needed);
+               pbe = pbe->next;
        }
-       if (!pbe) { /* get_zeroed_page() failed */
-               free_pagedir(pblist, 1);
-               pblist = NULL;
-        } else
-               create_pbe_list(pblist, nr_pages);
+       create_pbe_list(pblist, nr_pages);
        return pblist;
 }
 
@@ -481,13 +400,14 @@ static struct pbe *alloc_pagedir(unsigned int nr_pages, gfp_t gfp_mask,
 void swsusp_free(void)
 {
        struct zone *zone;
-       unsigned long zone_pfn;
+       unsigned long pfn, max_zone_pfn;
 
        for_each_zone(zone) {
-               for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn)
-                       if (pfn_valid(zone_pfn + zone->zone_start_pfn)) {
-                               struct page *page;
-                               page = pfn_to_page(zone_pfn + zone->zone_start_pfn);
+               max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
+               for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
+                       if (pfn_valid(pfn)) {
+                               struct page *page = pfn_to_page(pfn);
+
                                if (PageNosave(page) && PageNosaveFree(page)) {
                                        ClearPageNosave(page);
                                        ClearPageNosaveFree(page);
@@ -497,7 +417,7 @@ void swsusp_free(void)
        }
        nr_copy_pages = 0;
        nr_meta_pages = 0;
-       pagedir_nosave = NULL;
+       restore_pblist = NULL;
        buffer = NULL;
 }
 
@@ -572,15 +492,15 @@ asmlinkage int swsusp_save(void)
                return -ENOMEM;
        }
 
-       pagedir_nosave = swsusp_alloc(nr_pages);
-       if (!pagedir_nosave)
+       restore_pblist = swsusp_alloc(nr_pages);
+       if (!restore_pblist)
                return -ENOMEM;
 
        /* During allocating of suspend pagedir, new cold pages may appear.
         * Kill them.
         */
        drain_local_pages();
-       copy_data_pages(pagedir_nosave);
+       copy_data_pages(restore_pblist);
 
        /*
         * End of critical section. From now on, we can write to memory,
@@ -651,7 +571,7 @@ static inline struct pbe *pack_orig_addresses(unsigned long *buf, struct pbe *pb
 
 int snapshot_read_next(struct snapshot_handle *handle, size_t count)
 {
-       if (handle->page > nr_meta_pages + nr_copy_pages)
+       if (handle->cur > nr_meta_pages + nr_copy_pages)
                return 0;
        if (!buffer) {
                /* This makes the buffer be freed by swsusp_free() */
@@ -662,26 +582,26 @@ int snapshot_read_next(struct snapshot_handle *handle, size_t count)
        if (!handle->offset) {
                init_header((struct swsusp_info *)buffer);
                handle->buffer = buffer;
-               handle->pbe = pagedir_nosave;
+               handle->pbe = restore_pblist;
        }
-       if (handle->prev < handle->page) {
-               if (handle->page <= nr_meta_pages) {
+       if (handle->prev < handle->cur) {
+               if (handle->cur <= nr_meta_pages) {
                        handle->pbe = pack_orig_addresses(buffer, handle->pbe);
                        if (!handle->pbe)
-                               handle->pbe = pagedir_nosave;
+                               handle->pbe = restore_pblist;
                } else {
                        handle->buffer = (void *)handle->pbe->address;
                        handle->pbe = handle->pbe->next;
                }
-               handle->prev = handle->page;
+               handle->prev = handle->cur;
        }
-       handle->buf_offset = handle->page_offset;
-       if (handle->page_offset + count >= PAGE_SIZE) {
-               count = PAGE_SIZE - handle->page_offset;
-               handle->page_offset = 0;
-               handle->page++;
+       handle->buf_offset = handle->cur_offset;
+       if (handle->cur_offset + count >= PAGE_SIZE) {
+               count = PAGE_SIZE - handle->cur_offset;
+               handle->cur_offset = 0;
+               handle->cur++;
        } else {
-               handle->page_offset += count;
+               handle->cur_offset += count;
        }
        handle->offset += count;
        return count;
@@ -696,7 +616,7 @@ int snapshot_read_next(struct snapshot_handle *handle, size_t count)
 static int mark_unsafe_pages(struct pbe *pblist)
 {
        struct zone *zone;
-       unsigned long zone_pfn;
+       unsigned long pfn, max_zone_pfn;
        struct pbe *p;
 
        if (!pblist) /* a sanity check */
@@ -704,10 +624,10 @@ static int mark_unsafe_pages(struct pbe *pblist)
 
        /* Clear page flags */
        for_each_zone (zone) {
-               for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn)
-                       if (pfn_valid(zone_pfn + zone->zone_start_pfn))
-                               ClearPageNosaveFree(pfn_to_page(zone_pfn +
-                                       zone->zone_start_pfn));
+               max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
+               for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
+                       if (pfn_valid(pfn))
+                               ClearPageNosaveFree(pfn_to_page(pfn));
        }
 
        /* Mark orig addresses */
@@ -771,7 +691,7 @@ static int load_header(struct snapshot_handle *handle,
                pblist = alloc_pagedir(info->image_pages, GFP_ATOMIC, 0);
                if (!pblist)
                        return -ENOMEM;
-               pagedir_nosave = pblist;
+               restore_pblist = pblist;
                handle->pbe = pblist;
                nr_copy_pages = info->image_pages;
                nr_meta_pages = info->pages - info->image_pages - 1;
@@ -798,7 +718,7 @@ static inline struct pbe *unpack_orig_addresses(unsigned long *buf,
 
 /**
  *     prepare_image - use metadata contained in the PBE list
- *     pointed to by pagedir_nosave to mark the pages that will
+ *     pointed to by restore_pblist to mark the pages that will
  *     be overwritten in the process of restoring the system
  *     memory state from the image ("unsafe" pages) and allocate
  *     memory for the image
@@ -823,7 +743,7 @@ static int prepare_image(struct snapshot_handle *handle)
        unsigned int nr_pages = nr_copy_pages;
        struct pbe *p, *pblist = NULL;
 
-       p = pagedir_nosave;
+       p = restore_pblist;
        error = mark_unsafe_pages(p);
        if (!error) {
                pblist = alloc_pagedir(nr_pages, GFP_ATOMIC, 1);
@@ -855,7 +775,7 @@ static int prepare_image(struct snapshot_handle *handle)
                }
        }
        if (!error) {
-               pagedir_nosave = pblist;
+               restore_pblist = pblist;
        } else {
                handle->pbe = NULL;
                swsusp_free();
@@ -916,7 +836,7 @@ int snapshot_write_next(struct snapshot_handle *handle, size_t count)
 {
        int error = 0;
 
-       if (handle->prev && handle->page > nr_meta_pages + nr_copy_pages)
+       if (handle->prev && handle->cur > nr_meta_pages + nr_copy_pages)
                return 0;
        if (!buffer) {
                /* This makes the buffer be freed by swsusp_free() */
@@ -926,34 +846,39 @@ int snapshot_write_next(struct snapshot_handle *handle, size_t count)
        }
        if (!handle->offset)
                handle->buffer = buffer;
-       if (handle->prev < handle->page) {
+       handle->sync_read = 1;
+       if (handle->prev < handle->cur) {
                if (!handle->prev) {
-                       error = load_header(handle, (struct swsusp_info *)buffer);
+                       error = load_header(handle,
+                                       (struct swsusp_info *)buffer);
                        if (error)
                                return error;
                } else if (handle->prev <= nr_meta_pages) {
-                       handle->pbe = unpack_orig_addresses(buffer, handle->pbe);
+                       handle->pbe = unpack_orig_addresses(buffer,
+                                                       handle->pbe);
                        if (!handle->pbe) {
                                error = prepare_image(handle);
                                if (error)
                                        return error;
-                               handle->pbe = pagedir_nosave;
+                               handle->pbe = restore_pblist;
                                handle->last_pbe = NULL;
                                handle->buffer = get_buffer(handle);
+                               handle->sync_read = 0;
                        }
                } else {
                        handle->pbe = handle->pbe->next;
                        handle->buffer = get_buffer(handle);
+                       handle->sync_read = 0;
                }
-               handle->prev = handle->page;
+               handle->prev = handle->cur;
        }
-       handle->buf_offset = handle->page_offset;
-       if (handle->page_offset + count >= PAGE_SIZE) {
-               count = PAGE_SIZE - handle->page_offset;
-               handle->page_offset = 0;
-               handle->page++;
+       handle->buf_offset = handle->cur_offset;
+       if (handle->cur_offset + count >= PAGE_SIZE) {
+               count = PAGE_SIZE - handle->cur_offset;
+               handle->cur_offset = 0;
+               handle->cur++;
        } else {
-               handle->page_offset += count;
+               handle->cur_offset += count;
        }
        handle->offset += count;
        return count;
@@ -962,5 +887,5 @@ int snapshot_write_next(struct snapshot_handle *handle, size_t count)
 int snapshot_image_loaded(struct snapshot_handle *handle)
 {
        return !(!handle->pbe || handle->pbe->next || !nr_copy_pages ||
-               handle->page <= nr_meta_pages + nr_copy_pages);
+               handle->cur <= nr_meta_pages + nr_copy_pages);
 }