drm/vmwgfx: return -EFAULT for copy_to_user errors
[safe/jmp/linux-2.6] / kernel / power / swap.c
index a57c661..b0bb217 100644 (file)
  */
 
 #include <linux/module.h>
-#include <linux/smp_lock.h>
 #include <linux/file.h>
-#include <linux/utsname.h>
-#include <linux/version.h>
 #include <linux/delay.h>
 #include <linux/bitops.h>
 #include <linux/genhd.h>
 #include <linux/device.h>
 #include <linux/buffer_head.h>
 #include <linux/bio.h>
+#include <linux/blkdev.h>
 #include <linux/swap.h>
 #include <linux/swapops.h>
 #include <linux/pm.h>
+#include <linux/slab.h>
 
 #include "power.h"
 
-extern char resume_file[];
-
 #define SWSUSP_SIG     "S1SUSPEND"
 
-static struct swsusp_header {
-       char reserved[PAGE_SIZE - 20 - sizeof(swp_entry_t)];
-       swp_entry_t image;
+/*
+ *     The swap map is a data structure used for keeping track of each page
+ *     written to a swap partition.  It consists of many swap_map_page
+ *     structures that contain each an array of MAP_PAGE_SIZE swap entries.
+ *     These structures are stored on the swap and linked together with the
+ *     help of the .next_swap member.
+ *
+ *     The swap map is created during suspend.  The swap map pages are
+ *     allocated and populated one at a time, so we only need one memory
+ *     page to set up the entire structure.
+ *
+ *     During resume we also only need to use one swap_map_page structure
+ *     at a time.
+ */
+
+#define MAP_PAGE_ENTRIES       (PAGE_SIZE / sizeof(sector_t) - 1)
+
+struct swap_map_page {
+       sector_t entries[MAP_PAGE_ENTRIES];
+       sector_t next_swap;
+};
+
+/**
+ *     The swap_map_handle structure is used for handling swap in
+ *     a file-alike way
+ */
+
+struct swap_map_handle {
+       struct swap_map_page *cur;
+       sector_t cur_swap;
+       sector_t first_sector;
+       unsigned int k;
+};
+
+struct swsusp_header {
+       char reserved[PAGE_SIZE - 20 - sizeof(sector_t) - sizeof(int)];
+       sector_t image;
+       unsigned int flags;     /* Flags to pass to the "boot" kernel */
        char    orig_sig[10];
        char    sig[10];
-} __attribute__((packed, aligned(PAGE_SIZE))) swsusp_header;
+} __attribute__((packed));
+
+static struct swsusp_header *swsusp_header;
+
+/**
+ *     The following functions are used for tracing the allocated
+ *     swap pages, so that they can be freed in case of an error.
+ */
+
+struct swsusp_extent {
+       struct rb_node node;
+       unsigned long start;
+       unsigned long end;
+};
+
+static struct rb_root swsusp_extents = RB_ROOT;
+
+static int swsusp_extents_insert(unsigned long swap_offset)
+{
+       struct rb_node **new = &(swsusp_extents.rb_node);
+       struct rb_node *parent = NULL;
+       struct swsusp_extent *ext;
+
+       /* Figure out where to put the new node */
+       while (*new) {
+               ext = container_of(*new, struct swsusp_extent, node);
+               parent = *new;
+               if (swap_offset < ext->start) {
+                       /* Try to merge */
+                       if (swap_offset == ext->start - 1) {
+                               ext->start--;
+                               return 0;
+                       }
+                       new = &((*new)->rb_left);
+               } else if (swap_offset > ext->end) {
+                       /* Try to merge */
+                       if (swap_offset == ext->end + 1) {
+                               ext->end++;
+                               return 0;
+                       }
+                       new = &((*new)->rb_right);
+               } else {
+                       /* It already is in the tree */
+                       return -EINVAL;
+               }
+       }
+       /* Add the new node and rebalance the tree. */
+       ext = kzalloc(sizeof(struct swsusp_extent), GFP_KERNEL);
+       if (!ext)
+               return -ENOMEM;
+
+       ext->start = swap_offset;
+       ext->end = swap_offset;
+       rb_link_node(&ext->node, parent, new);
+       rb_insert_color(&ext->node, &swsusp_extents);
+       return 0;
+}
+
+/**
+ *     alloc_swapdev_block - allocate a swap page and register that it has
+ *     been allocated, so that it can be freed in case of an error.
+ */
+
+sector_t alloc_swapdev_block(int swap)
+{
+       unsigned long offset;
+
+       offset = swp_offset(get_swap_page_of_type(swap));
+       if (offset) {
+               if (swsusp_extents_insert(offset))
+                       swap_free(swp_entry(swap, offset));
+               else
+                       return swapdev_block(swap, offset);
+       }
+       return 0;
+}
+
+/**
+ *     free_all_swap_pages - free swap pages allocated for saving image data.
+ *     It also frees the extents used to register which swap entres had been
+ *     allocated.
+ */
+
+void free_all_swap_pages(int swap)
+{
+       struct rb_node *node;
+
+       while ((node = swsusp_extents.rb_node)) {
+               struct swsusp_extent *ext;
+               unsigned long offset;
+
+               ext = container_of(node, struct swsusp_extent, node);
+               rb_erase(node, &swsusp_extents);
+               for (offset = ext->start; offset <= ext->end; offset++)
+                       swap_free(swp_entry(swap, offset));
+
+               kfree(ext);
+       }
+}
+
+int swsusp_swap_in_use(void)
+{
+       return (swsusp_extents.rb_node != NULL);
+}
 
 /*
- * Saving part...
+ * General things
  */
 
 static unsigned short root_swap = 0xffff;
+struct block_device *hib_resume_bdev;
+
+/*
+ * Saving part
+ */
 
-static int mark_swapfiles(swp_entry_t start)
+static int mark_swapfiles(struct swap_map_handle *handle, unsigned int flags)
 {
        int error;
 
-       rw_swap_page_sync(READ,
-                         swp_entry(root_swap, 0),
-                         virt_to_page((unsigned long)&swsusp_header));
-       if (!memcmp("SWAP-SPACE",swsusp_header.sig, 10) ||
-           !memcmp("SWAPSPACE2",swsusp_header.sig, 10)) {
-               memcpy(swsusp_header.orig_sig,swsusp_header.sig, 10);
-               memcpy(swsusp_header.sig,SWSUSP_SIG, 10);
-               swsusp_header.image = start;
-               error = rw_swap_page_sync(WRITE,
-                                         swp_entry(root_swap, 0),
-                                         virt_to_page((unsigned long)
-                                                      &swsusp_header));
+       hib_bio_read_page(swsusp_resume_block, swsusp_header, NULL);
+       if (!memcmp("SWAP-SPACE",swsusp_header->sig, 10) ||
+           !memcmp("SWAPSPACE2",swsusp_header->sig, 10)) {
+               memcpy(swsusp_header->orig_sig,swsusp_header->sig, 10);
+               memcpy(swsusp_header->sig,SWSUSP_SIG, 10);
+               swsusp_header->image = handle->first_sector;
+               swsusp_header->flags = flags;
+               error = hib_bio_write_page(swsusp_resume_block,
+                                       swsusp_header, NULL);
        } else {
-               pr_debug("swsusp: Partition is not swap space.\n");
+               printk(KERN_ERR "PM: Swap header not found!\n");
                error = -ENODEV;
        }
        return error;
@@ -71,16 +208,27 @@ static int mark_swapfiles(swp_entry_t start)
 /**
  *     swsusp_swap_check - check if the resume device is a swap device
  *     and get its index (if so)
+ *
+ *     This is called before saving image
  */
-
-static int swsusp_swap_check(void) /* This is called before saving image */
+static int swsusp_swap_check(void)
 {
-       int res = swap_type_of(swsusp_resume_device);
+       int res;
+
+       res = swap_type_of(swsusp_resume_device, swsusp_resume_block,
+                       &hib_resume_bdev);
+       if (res < 0)
+               return res;
+
+       root_swap = res;
+       res = blkdev_get(hib_resume_bdev, FMODE_WRITE);
+       if (res)
+               return res;
+
+       res = set_blocksize(hib_resume_bdev, PAGE_SIZE);
+       if (res < 0)
+               blkdev_put(hib_resume_bdev, FMODE_WRITE);
 
-       if (res >= 0) {
-               root_swap = res;
-               return 0;
-       }
        return res;
 }
 
@@ -88,149 +236,172 @@ static int swsusp_swap_check(void) /* This is called before saving image */
  *     write_page - Write one page to given swap location.
  *     @buf:           Address we're writing.
  *     @offset:        Offset of the swap page we're writing to.
+ *     @bio_chain:     Link the next write BIO here
  */
 
-static int write_page(void *buf, unsigned long offset)
+static int write_page(void *buf, sector_t offset, struct bio **bio_chain)
 {
-       swp_entry_t entry;
-       int error = -ENOSPC;
+       void *src;
 
-       if (offset) {
-               entry = swp_entry(root_swap, offset);
-               error = rw_swap_page_sync(WRITE, entry, virt_to_page(buf));
+       if (!offset)
+               return -ENOSPC;
+
+       if (bio_chain) {
+               src = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH);
+               if (src) {
+                       memcpy(src, buf, PAGE_SIZE);
+               } else {
+                       WARN_ON_ONCE(1);
+                       bio_chain = NULL;       /* Go synchronous */
+                       src = buf;
+               }
+       } else {
+               src = buf;
        }
-       return error;
+       return hib_bio_write_page(offset, src, bio_chain);
 }
 
-/*
- *     The swap map is a data structure used for keeping track of each page
- *     written to a swap partition.  It consists of many swap_map_page
- *     structures that contain each an array of MAP_PAGE_SIZE swap entries.
- *     These structures are stored on the swap and linked together with the
- *     help of the .next_swap member.
- *
- *     The swap map is created during suspend.  The swap map pages are
- *     allocated and populated one at a time, so we only need one memory
- *     page to set up the entire structure.
- *
- *     During resume we also only need to use one swap_map_page structure
- *     at a time.
- */
-
-#define MAP_PAGE_ENTRIES       (PAGE_SIZE / sizeof(long) - 1)
-
-struct swap_map_page {
-       unsigned long           entries[MAP_PAGE_ENTRIES];
-       unsigned long           next_swap;
-};
-
-/**
- *     The swap_map_handle structure is used for handling swap in
- *     a file-alike way
- */
-
-struct swap_map_handle {
-       struct swap_map_page *cur;
-       unsigned long cur_swap;
-       struct bitmap_page *bitmap;
-       unsigned int k;
-};
-
 static void release_swap_writer(struct swap_map_handle *handle)
 {
        if (handle->cur)
                free_page((unsigned long)handle->cur);
        handle->cur = NULL;
-       if (handle->bitmap)
-               free_bitmap(handle->bitmap);
-       handle->bitmap = NULL;
 }
 
 static int get_swap_writer(struct swap_map_handle *handle)
 {
+       int ret;
+
+       ret = swsusp_swap_check();
+       if (ret) {
+               if (ret != -ENOSPC)
+                       printk(KERN_ERR "PM: Cannot find swap device, try "
+                                       "swapon -a.\n");
+               return ret;
+       }
        handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_KERNEL);
-       if (!handle->cur)
-               return -ENOMEM;
-       handle->bitmap = alloc_bitmap(count_swap_pages(root_swap, 0));
-       if (!handle->bitmap) {
-               release_swap_writer(handle);
-               return -ENOMEM;
+       if (!handle->cur) {
+               ret = -ENOMEM;
+               goto err_close;
        }
-       handle->cur_swap = alloc_swap_page(root_swap, handle->bitmap);
+       handle->cur_swap = alloc_swapdev_block(root_swap);
        if (!handle->cur_swap) {
-               release_swap_writer(handle);
-               return -ENOSPC;
+               ret = -ENOSPC;
+               goto err_rel;
        }
        handle->k = 0;
+       handle->first_sector = handle->cur_swap;
        return 0;
+err_rel:
+       release_swap_writer(handle);
+err_close:
+       swsusp_close(FMODE_WRITE);
+       return ret;
 }
 
-static int swap_write_page(struct swap_map_handle *handle, void *buf)
+static int swap_write_page(struct swap_map_handle *handle, void *buf,
+                               struct bio **bio_chain)
 {
-       int error;
-       unsigned long offset;
+       int error = 0;
+       sector_t offset;
 
        if (!handle->cur)
                return -EINVAL;
-       offset = alloc_swap_page(root_swap, handle->bitmap);
-       error = write_page(buf, offset);
+       offset = alloc_swapdev_block(root_swap);
+       error = write_page(buf, offset, bio_chain);
        if (error)
                return error;
        handle->cur->entries[handle->k++] = offset;
        if (handle->k >= MAP_PAGE_ENTRIES) {
-               offset = alloc_swap_page(root_swap, handle->bitmap);
+               error = hib_wait_on_bio_chain(bio_chain);
+               if (error)
+                       goto out;
+               offset = alloc_swapdev_block(root_swap);
                if (!offset)
                        return -ENOSPC;
                handle->cur->next_swap = offset;
-               error = write_page(handle->cur, handle->cur_swap);
+               error = write_page(handle->cur, handle->cur_swap, NULL);
                if (error)
-                       return error;
+                       goto out;
                memset(handle->cur, 0, PAGE_SIZE);
                handle->cur_swap = offset;
                handle->k = 0;
        }
-       return 0;
+ out:
+       return error;
 }
 
 static int flush_swap_writer(struct swap_map_handle *handle)
 {
        if (handle->cur && handle->cur_swap)
-               return write_page(handle->cur, handle->cur_swap);
+               return write_page(handle->cur, handle->cur_swap, NULL);
        else
                return -EINVAL;
 }
 
+static int swap_writer_finish(struct swap_map_handle *handle,
+               unsigned int flags, int error)
+{
+       if (!error) {
+               flush_swap_writer(handle);
+               printk(KERN_INFO "PM: S");
+               error = mark_swapfiles(handle, flags);
+               printk("|\n");
+       }
+
+       if (error)
+               free_all_swap_pages(root_swap);
+       release_swap_writer(handle);
+       swsusp_close(FMODE_WRITE);
+
+       return error;
+}
+
 /**
  *     save_image - save the suspend image data
  */
 
 static int save_image(struct swap_map_handle *handle,
                       struct snapshot_handle *snapshot,
-                      unsigned int nr_pages)
+                      unsigned int nr_to_write)
 {
        unsigned int m;
        int ret;
-       int error = 0;
+       int nr_pages;
+       int err2;
+       struct bio *bio;
+       struct timeval start;
+       struct timeval stop;
 
-       printk("Saving image data pages (%u pages) ...     ", nr_pages);
-       m = nr_pages / 100;
+       printk(KERN_INFO "PM: Saving image data pages (%u pages) ...     ",
+               nr_to_write);
+       m = nr_to_write / 100;
        if (!m)
                m = 1;
        nr_pages = 0;
-       do {
-               ret = snapshot_read_next(snapshot, PAGE_SIZE);
-               if (ret > 0) {
-                       error = swap_write_page(handle, data_of(*snapshot));
-                       if (error)
-                               break;
-                       if (!(nr_pages % m))
-                               printk("\b\b\b\b%3d%%", nr_pages / m);
-                       nr_pages++;
-               }
-       } while (ret > 0);
-       if (!error)
-               printk("\b\b\b\bdone\n");
-       return error;
+       bio = NULL;
+       do_gettimeofday(&start);
+       while (1) {
+               ret = snapshot_read_next(snapshot);
+               if (ret <= 0)
+                       break;
+               ret = swap_write_page(handle, data_of(*snapshot), &bio);
+               if (ret)
+                       break;
+               if (!(nr_pages % m))
+                       printk(KERN_CONT "\b\b\b\b%3d%%", nr_pages / m);
+               nr_pages++;
+       }
+       err2 = hib_wait_on_bio_chain(&bio);
+       do_gettimeofday(&stop);
+       if (!ret)
+               ret = err2;
+       if (!ret)
+               printk(KERN_CONT "\b\b\b\bdone\n");
+       else
+               printk(KERN_CONT "\n");
+       swsusp_show_speed(&start, &stop, nr_to_write, "Wrote");
+       return ret;
 }
 
 /**
@@ -244,13 +415,13 @@ static int enough_swap(unsigned int nr_pages)
 {
        unsigned int free_swap = count_swap_pages(root_swap, 1);
 
-       pr_debug("swsusp: free swap pages: %u\n", free_swap);
-       return free_swap > (nr_pages + PAGES_FOR_IO +
-               (nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE);
+       pr_debug("PM: Free swap pages: %u\n", free_swap);
+       return free_swap > nr_pages + PAGES_FOR_IO;
 }
 
 /**
  *     swsusp_write - Write entire image and metadata.
+ *     @flags: flags to pass to the "boot" kernel in the image header
  *
  *     It is important _NOT_ to umount filesystems at this point. We want
  *     them synced (in case something goes wrong) but we DO not want to mark
@@ -258,117 +429,42 @@ static int enough_swap(unsigned int nr_pages)
  *     correctly, we'll mark system clean, anyway.)
  */
 
-int swsusp_write(void)
+int swsusp_write(unsigned int flags)
 {
        struct swap_map_handle handle;
        struct snapshot_handle snapshot;
        struct swsusp_info *header;
+       unsigned long pages;
        int error;
 
-       if ((error = swsusp_swap_check())) {
-               printk(KERN_ERR "swsusp: Cannot find swap device, try swapon -a.\n");
+       pages = snapshot_get_image_size();
+       error = get_swap_writer(&handle);
+       if (error) {
+               printk(KERN_ERR "PM: Cannot get swap writer\n");
                return error;
        }
-       memset(&snapshot, 0, sizeof(struct snapshot_handle));
-       error = snapshot_read_next(&snapshot, PAGE_SIZE);
-       if (error < PAGE_SIZE)
-               return error < 0 ? error : -EFAULT;
-       header = (struct swsusp_info *)data_of(snapshot);
-       if (!enough_swap(header->pages)) {
-               printk(KERN_ERR "swsusp: Not enough free swap\n");
-               return -ENOSPC;
-       }
-       error = get_swap_writer(&handle);
-       if (!error) {
-               unsigned long start = handle.cur_swap;
-               error = swap_write_page(&handle, header);
-               if (!error)
-                       error = save_image(&handle, &snapshot,
-                                       header->pages - 1);
-               if (!error) {
-                       flush_swap_writer(&handle);
-                       printk("S");
-                       error = mark_swapfiles(swp_entry(root_swap, start));
-                       printk("|\n");
-               }
+       if (!enough_swap(pages)) {
+               printk(KERN_ERR "PM: Not enough free swap\n");
+               error = -ENOSPC;
+               goto out_finish;
        }
-       if (error)
-               free_all_swap_pages(root_swap, handle.bitmap);
-       release_swap_writer(&handle);
-       return error;
-}
-
-/*
- *     Using bio to read from swap.
- *     This code requires a bit more work than just using buffer heads
- *     but, it is the recommended way for 2.5/2.6.
- *     The following are to signal the beginning and end of I/O. Bios
- *     finish asynchronously, while we want them to happen synchronously.
- *     A simple atomic_t, and a wait loop take care of this problem.
- */
-
-static atomic_t io_done = ATOMIC_INIT(0);
-
-static int end_io(struct bio *bio, unsigned int num, int err)
-{
-       if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
-               panic("I/O error reading memory image");
-       atomic_set(&io_done, 0);
-       return 0;
-}
-
-static struct block_device *resume_bdev;
-
-/**
- *     submit - submit BIO request.
- *     @rw:    READ or WRITE.
- *     @off    physical offset of page.
- *     @page:  page we're reading or writing.
- *
- *     Straight from the textbook - allocate and initialize the bio.
- *     If we're writing, make sure the page is marked as dirty.
- *     Then submit it and wait.
- */
-
-static int submit(int rw, pgoff_t page_off, void *page)
-{
-       int error = 0;
-       struct bio *bio;
+       memset(&snapshot, 0, sizeof(struct snapshot_handle));
+       error = snapshot_read_next(&snapshot);
+       if (error < PAGE_SIZE) {
+               if (error >= 0)
+                       error = -EFAULT;
 
-       bio = bio_alloc(GFP_ATOMIC, 1);
-       if (!bio)
-               return -ENOMEM;
-       bio->bi_sector = page_off * (PAGE_SIZE >> 9);
-       bio->bi_bdev = resume_bdev;
-       bio->bi_end_io = end_io;
-
-       if (bio_add_page(bio, virt_to_page(page), PAGE_SIZE, 0) < PAGE_SIZE) {
-               printk("swsusp: ERROR: adding page to bio at %ld\n",page_off);
-               error = -EFAULT;
-               goto Done;
+               goto out_finish;
        }
-
-       atomic_set(&io_done, 1);
-       submit_bio(rw | (1 << BIO_RW_SYNC), bio);
-       while (atomic_read(&io_done))
-               yield();
-       if (rw == READ)
-               bio_set_pages_dirty(bio);
- Done:
-       bio_put(bio);
+       header = (struct swsusp_info *)data_of(snapshot);
+       error = swap_write_page(&handle, header, NULL);
+       if (!error)
+               error = save_image(&handle, &snapshot, pages - 1);
+out_finish:
+       error = swap_writer_finish(&handle, flags, error);
        return error;
 }
 
-static int bio_read_page(pgoff_t page_off, void *page)
-{
-       return submit(READ, page_off, page);
-}
-
-static int bio_write_page(pgoff_t page_off, void *page)
-{
-       return submit(WRITE, page_off, page);
-}
-
 /**
  *     The following functions allow us to read data using a swap map
  *     in a file-alike way
@@ -382,16 +478,20 @@ static void release_swap_reader(struct swap_map_handle *handle)
 }
 
 static int get_swap_reader(struct swap_map_handle *handle,
-                                      swp_entry_t start)
+               unsigned int *flags_p)
 {
        int error;
 
-       if (!swp_offset(start))
+       *flags_p = swsusp_header->flags;
+
+       if (!swsusp_header->image) /* how can this happen? */
                return -EINVAL;
-       handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_ATOMIC);
+
+       handle->cur = (struct swap_map_page *)get_zeroed_page(__GFP_WAIT | __GFP_HIGH);
        if (!handle->cur)
                return -ENOMEM;
-       error = bio_read_page(swp_offset(start), handle->cur);
+
+       error = hib_bio_read_page(swsusp_header->image, handle->cur, NULL);
        if (error) {
                release_swap_reader(handle);
                return error;
@@ -400,9 +500,10 @@ static int get_swap_reader(struct swap_map_handle *handle,
        return 0;
 }
 
-static int swap_read_page(struct swap_map_handle *handle, void *buf)
+static int swap_read_page(struct swap_map_handle *handle, void *buf,
+                               struct bio **bio_chain)
 {
-       unsigned long offset;
+       sector_t offset;
        int error;
 
        if (!handle->cur)
@@ -410,20 +511,28 @@ static int swap_read_page(struct swap_map_handle *handle, void *buf)
        offset = handle->cur->entries[handle->k];
        if (!offset)
                return -EFAULT;
-       error = bio_read_page(offset, buf);
+       error = hib_bio_read_page(offset, buf, bio_chain);
        if (error)
                return error;
        if (++handle->k >= MAP_PAGE_ENTRIES) {
+               error = hib_wait_on_bio_chain(bio_chain);
                handle->k = 0;
                offset = handle->cur->next_swap;
                if (!offset)
                        release_swap_reader(handle);
-               else
-                       error = bio_read_page(offset, handle->cur);
+               else if (!error)
+                       error = hib_bio_read_page(offset, handle->cur, NULL);
        }
        return error;
 }
 
+static int swap_reader_finish(struct swap_map_handle *handle)
+{
+       release_swap_reader(handle);
+
+       return 0;
+}
+
 /**
  *     load_image - load the image using the swap map handle
  *     @handle and the snapshot handle @snapshot
@@ -432,66 +541,85 @@ static int swap_read_page(struct swap_map_handle *handle, void *buf)
 
 static int load_image(struct swap_map_handle *handle,
                       struct snapshot_handle *snapshot,
-                      unsigned int nr_pages)
+                      unsigned int nr_to_read)
 {
        unsigned int m;
-       int ret;
        int error = 0;
+       struct timeval start;
+       struct timeval stop;
+       struct bio *bio;
+       int err2;
+       unsigned nr_pages;
 
-       printk("Loading image data pages (%u pages) ...     ", nr_pages);
-       m = nr_pages / 100;
+       printk(KERN_INFO "PM: Loading image data pages (%u pages) ...     ",
+               nr_to_read);
+       m = nr_to_read / 100;
        if (!m)
                m = 1;
        nr_pages = 0;
-       do {
-               ret = snapshot_write_next(snapshot, PAGE_SIZE);
-               if (ret > 0) {
-                       error = swap_read_page(handle, data_of(*snapshot));
-                       if (error)
-                               break;
-                       if (!(nr_pages % m))
-                               printk("\b\b\b\b%3d%%", nr_pages / m);
-                       nr_pages++;
-               }
-       } while (ret > 0);
+       bio = NULL;
+       do_gettimeofday(&start);
+       for ( ; ; ) {
+               error = snapshot_write_next(snapshot);
+               if (error <= 0)
+                       break;
+               error = swap_read_page(handle, data_of(*snapshot), &bio);
+               if (error)
+                       break;
+               if (snapshot->sync_read)
+                       error = hib_wait_on_bio_chain(&bio);
+               if (error)
+                       break;
+               if (!(nr_pages % m))
+                       printk("\b\b\b\b%3d%%", nr_pages / m);
+               nr_pages++;
+       }
+       err2 = hib_wait_on_bio_chain(&bio);
+       do_gettimeofday(&stop);
+       if (!error)
+               error = err2;
        if (!error) {
                printk("\b\b\b\bdone\n");
+               snapshot_write_finalize(snapshot);
                if (!snapshot_image_loaded(snapshot))
                        error = -ENODATA;
-       }
+       } else
+               printk("\n");
+       swsusp_show_speed(&start, &stop, nr_to_read, "Read");
        return error;
 }
 
-int swsusp_read(void)
+/**
+ *     swsusp_read - read the hibernation image.
+ *     @flags_p: flags passed by the "frozen" kernel in the image header should
+ *               be written into this memeory location
+ */
+
+int swsusp_read(unsigned int *flags_p)
 {
        int error;
        struct swap_map_handle handle;
        struct snapshot_handle snapshot;
        struct swsusp_info *header;
 
-       if (IS_ERR(resume_bdev)) {
-               pr_debug("swsusp: block device not initialised\n");
-               return PTR_ERR(resume_bdev);
-       }
-
        memset(&snapshot, 0, sizeof(struct snapshot_handle));
-       error = snapshot_write_next(&snapshot, PAGE_SIZE);
+       error = snapshot_write_next(&snapshot);
        if (error < PAGE_SIZE)
                return error < 0 ? error : -EFAULT;
        header = (struct swsusp_info *)data_of(snapshot);
-       error = get_swap_reader(&handle, swsusp_header.image);
+       error = get_swap_reader(&handle, flags_p);
+       if (error)
+               goto end;
        if (!error)
-               error = swap_read_page(&handle, header);
+               error = swap_read_page(&handle, header, NULL);
        if (!error)
                error = load_image(&handle, &snapshot, header->pages - 1);
-       release_swap_reader(&handle);
-
-       blkdev_put(resume_bdev);
-
+       swap_reader_finish(&handle);
+end:
        if (!error)
-               pr_debug("swsusp: Reading resume file was successful\n");
+               pr_debug("PM: Image successfully loaded\n");
        else
-               pr_debug("swsusp: Error %d resuming\n", error);
+               pr_debug("PM: Error %d resuming\n", error);
        return error;
 }
 
@@ -503,29 +631,35 @@ int swsusp_check(void)
 {
        int error;
 
-       resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ);
-       if (!IS_ERR(resume_bdev)) {
-               set_blocksize(resume_bdev, PAGE_SIZE);
-               memset(&swsusp_header, 0, sizeof(swsusp_header));
-               if ((error = bio_read_page(0, &swsusp_header)))
-                       return error;
-               if (!memcmp(SWSUSP_SIG, swsusp_header.sig, 10)) {
-                       memcpy(swsusp_header.sig, swsusp_header.orig_sig, 10);
+       hib_resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ);
+       if (!IS_ERR(hib_resume_bdev)) {
+               set_blocksize(hib_resume_bdev, PAGE_SIZE);
+               memset(swsusp_header, 0, PAGE_SIZE);
+               error = hib_bio_read_page(swsusp_resume_block,
+                                       swsusp_header, NULL);
+               if (error)
+                       goto put;
+
+               if (!memcmp(SWSUSP_SIG, swsusp_header->sig, 10)) {
+                       memcpy(swsusp_header->sig, swsusp_header->orig_sig, 10);
                        /* Reset swap signature now */
-                       error = bio_write_page(0, &swsusp_header);
+                       error = hib_bio_write_page(swsusp_resume_block,
+                                               swsusp_header, NULL);
                } else {
-                       return -EINVAL;
+                       error = -EINVAL;
                }
+
+put:
                if (error)
-                       blkdev_put(resume_bdev);
+                       blkdev_put(hib_resume_bdev, FMODE_READ);
                else
-                       pr_debug("swsusp: Signature found, resuming\n");
+                       pr_debug("PM: Signature found, resuming\n");
        } else {
-               error = PTR_ERR(resume_bdev);
+               error = PTR_ERR(hib_resume_bdev);
        }
 
        if (error)
-               pr_debug("swsusp: Error %d check for resume file\n", error);
+               pr_debug("PM: Error %d checking image file\n", error);
 
        return error;
 }
@@ -534,12 +668,22 @@ int swsusp_check(void)
  *     swsusp_close - close swap device.
  */
 
-void swsusp_close(void)
+void swsusp_close(fmode_t mode)
 {
-       if (IS_ERR(resume_bdev)) {
-               pr_debug("swsusp: block device not initialised\n");
+       if (IS_ERR(hib_resume_bdev)) {
+               pr_debug("PM: Image device not initialised\n");
                return;
        }
 
-       blkdev_put(resume_bdev);
+       blkdev_put(hib_resume_bdev, mode);
 }
+
+static int swsusp_header_init(void)
+{
+       swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL);
+       if (!swsusp_header)
+               panic("Could not allocate memory for swsusp_header\n");
+       return 0;
+}
+
+core_initcall(swsusp_header_init);