6 files changed, 337 insertions, 311 deletions

diff --git a/kernel/power/Makefile b/kernel/power/Makefile
index 43191815f874..524e058dcf06 100644
--- a/kernel/power/Makefile
+++ b/kernel/power/Makefile
@@ -8,7 +8,8 @@ obj-$(CONFIG_PM_SLEEP)		+= console.o
 obj-$(CONFIG_FREEZER)           += process.o
 obj-$(CONFIG_SUSPEND)           += suspend.o
 obj-$(CONFIG_PM_TEST_SUSPEND)   += suspend_test.o
-obj-$(CONFIG_HIBERNATION)       += hibernate.o snapshot.o swap.o user.o
+obj-$(CONFIG_HIBERNATION)       += hibernate.o snapshot.o swap.o user.o \
+                                   block_io.o
 obj-$(CONFIG_HIBERNATION_NVS)   += hibernate_nvs.o
 
 obj-$(CONFIG_MAGIC_SYSRQ)       += poweroff.o
diff --git a/kernel/power/block_io.c b/kernel/power/block_io.c
new file mode 100644
index 000000000000..97024fd40cd5
--- /dev/null
+++ b/kernel/power/block_io.c
@@ -0,0 +1,103 @@
+/*
+ * This file provides functions for block I/O operations on swap/file.
+ *
+ * Copyright (C) 1998,2001-2005 Pavel Machek <pavel@ucw.cz>
+ * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl>
+ *
+ * This file is released under the GPLv2.
+ */
+
+#include <linux/bio.h>
+#include <linux/kernel.h>
+#include <linux/pagemap.h>
+#include <linux/swap.h>
+
+#include "power.h"
+
+/**
+ *      submit - submit BIO request.
+ *      @rw:    READ or WRITE.
+ *      @off    physical offset of page.
+ *      @page:  page we're reading or writing.
+ *      @bio_chain: list of pending biod (for async reading)
+ *
+ *      Straight from the textbook - allocate and initialize the bio.
+ *      If we're reading, make sure the page is marked as dirty.
+ *      Then submit it and, if @bio_chain == NULL, wait.
+ */
+static int submit(int rw, struct block_device *bdev, sector_t sector,
+                struct page *page, struct bio **bio_chain)
+{
+        const int bio_rw = rw | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG);
+        struct bio *bio;
+
+        bio = bio_alloc(__GFP_WAIT | __GFP_HIGH, 1);
+        bio->bi_sector = sector;
+        bio->bi_bdev = bdev;
+        bio->bi_end_io = end_swap_bio_read;
+
+        if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
+                printk(KERN_ERR "PM: Adding page to bio failed at %llu\n",
+                        (unsigned long long)sector);
+                bio_put(bio);
+                return -EFAULT;
+        }
+
+        lock_page(page);
+        bio_get(bio);
+
+        if (bio_chain == NULL) {
+                submit_bio(bio_rw, bio);
+                wait_on_page_locked(page);
+                if (rw == READ)
+                        bio_set_pages_dirty(bio);
+                bio_put(bio);
+        } else {
+                if (rw == READ)
+                        get_page(page); /* These pages are freed later */
+                bio->bi_private = *bio_chain;
+                *bio_chain = bio;
+                submit_bio(bio_rw, bio);
+        }
+        return 0;
+}
+
+int hib_bio_read_page(pgoff_t page_off, void *addr, struct bio **bio_chain)
+{
+        return submit(READ, hib_resume_bdev, page_off * (PAGE_SIZE >> 9),
+                        virt_to_page(addr), bio_chain);
+}
+
+int hib_bio_write_page(pgoff_t page_off, void *addr, struct bio **bio_chain)
+{
+        return submit(WRITE, hib_resume_bdev, page_off * (PAGE_SIZE >> 9),
+                        virt_to_page(addr), bio_chain);
+}
+
+int hib_wait_on_bio_chain(struct bio **bio_chain)
+{
+        struct bio *bio;
+        struct bio *next_bio;
+        int ret = 0;
+
+        if (bio_chain == NULL)
+                return 0;
+
+        bio = *bio_chain;
+        if (bio == NULL)
+                return 0;
+        while (bio) {
+                struct page *page;
+
+                next_bio = bio->bi_private;
+                page = bio->bi_io_vec[0].bv_page;
+                wait_on_page_locked(page);
+                if (!PageUptodate(page) || PageError(page))
+                        ret = -EIO;
+                put_page(page);
+                bio_put(bio);
+                bio = next_bio;
+        }
+        *bio_chain = NULL;
+        return ret;
+}
diff --git a/kernel/power/power.h b/kernel/power/power.h
index 46c5a26630a3..006270fe382d 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -97,24 +97,12 @@ extern int hibernate_preallocate_memory(void);
  */
 
 struct snapshot_handle {
-        loff_t          offset; /* number of the last byte ready for reading
-                                 * or writing in the sequence
-                                 */
         unsigned int    cur;    /* number of the block of PAGE_SIZE bytes the
                                  * next operation will refer to (ie. current)
                                  */
-        unsigned int    cur_offset;     /* offset with respect to the current
-                                         * block (for the next operation)
-                                         */
-        unsigned int    prev;   /* number of the block of PAGE_SIZE bytes that
-                                 * was the current one previously
-                                 */
         void            *buffer;        /* address of the block to read from
                                          * or write to
                                          */
-        unsigned int    buf_offset;     /* location to read from or write to,
-                                         * given as a displacement from 'buffer'
-                                         */
         int             sync_read;      /* Set to one to notify the caller of
                                          * snapshot_write_next() that it may
                                          * need to call wait_on_bio_chain()
@@ -125,12 +113,12 @@ struct snapshot_handle {
  * snapshot_read_next()/snapshot_write_next() is allowed to
  * read/write data after the function returns
  */
-#define data_of(handle) ((handle).buffer + (handle).buf_offset)
+#define data_of(handle) ((handle).buffer)
 
 extern unsigned int snapshot_additional_pages(struct zone *zone);
 extern unsigned long snapshot_get_image_size(void);
-extern int snapshot_read_next(struct snapshot_handle *handle, size_t count);
-extern int snapshot_write_next(struct snapshot_handle *handle, size_t count);
+extern int snapshot_read_next(struct snapshot_handle *handle);
+extern int snapshot_write_next(struct snapshot_handle *handle);
 extern void snapshot_write_finalize(struct snapshot_handle *handle);
 extern int snapshot_image_loaded(struct snapshot_handle *handle);
 
@@ -154,6 +142,15 @@ extern int swsusp_read(unsigned int *flags_p);
 extern int swsusp_write(unsigned int flags);
 extern void swsusp_close(fmode_t);
 
+/* kernel/power/block_io.c */
+extern struct block_device *hib_resume_bdev;
+
+extern int hib_bio_read_page(pgoff_t page_off, void *addr,
+                struct bio **bio_chain);
+extern int hib_bio_write_page(pgoff_t page_off, void *addr,
+                struct bio **bio_chain);
+extern int hib_wait_on_bio_chain(struct bio **bio_chain);
+
 struct timeval;
 /* kernel/power/swsusp.c */
 extern void swsusp_show_speed(struct timeval *, struct timeval *,
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index be861c26dda7..25ce010e9f8b 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -1604,14 +1604,9 @@ pack_pfns(unsigned long *buf, struct memory_bitmap *bm)
  *      snapshot_handle structure.  The structure gets updated and a pointer
  *      to it should be passed to this function every next time.
  *
- *      The @count parameter should contain the number of bytes the caller
- *      wants to read from the snapshot.  It must not be zero.
- *
  *      On success the function returns a positive number.  Then, the caller
  *      is allowed to read up to the returned number of bytes from the memory
- *      location computed by the data_of() macro.  The number returned
- *      may be smaller than @count, but this only happens if the read would
- *      cross a page boundary otherwise.
+ *      location computed by the data_of() macro.
  *
  *      The function returns 0 to indicate the end of data stream condition,
  *      and a negative number is returned on error.  In such cases the
@@ -1619,7 +1614,7 @@ pack_pfns(unsigned long *buf, struct memory_bitmap *bm)
  *      any more.
  */
 
-int snapshot_read_next(struct snapshot_handle *handle, size_t count)
+int snapshot_read_next(struct snapshot_handle *handle)
 {
         if (handle->cur > nr_meta_pages + nr_copy_pages)
                 return 0;
@@ -1630,7 +1625,7 @@ int snapshot_read_next(struct snapshot_handle *handle, size_t count)
                 if (!buffer)
                         return -ENOMEM;
         }
-        if (!handle->offset) {
+        if (!handle->cur) {
                 int error;
 
                 error = init_header((struct swsusp_info *)buffer);
@@ -1639,42 +1634,30 @@ int snapshot_read_next(struct snapshot_handle *handle, size_t count)
                 handle->buffer = buffer;
                 memory_bm_position_reset(&orig_bm);
                 memory_bm_position_reset(&copy_bm);
-        }
-        if (handle->prev < handle->cur) {
-                if (handle->cur <= nr_meta_pages) {
-                        memset(buffer, 0, PAGE_SIZE);
-                        pack_pfns(buffer, &orig_bm);
-                } else {
-                        struct page *page;
+        } else if (handle->cur <= nr_meta_pages) {
+                memset(buffer, 0, PAGE_SIZE);
+                pack_pfns(buffer, &orig_bm);
+        } else {
+                struct page *page;
 
-                        page = pfn_to_page(memory_bm_next_pfn(&copy_bm));
-                        if (PageHighMem(page)) {
-                                /* Highmem pages are copied to the buffer,
-                                 * because we can't return with a kmapped
-                                 * highmem page (we may not be called again).
-                                 */
-                                void *kaddr;
+                page = pfn_to_page(memory_bm_next_pfn(&copy_bm));
+                if (PageHighMem(page)) {
+                        /* Highmem pages are copied to the buffer,
+                         * because we can't return with a kmapped
+                         * highmem page (we may not be called again).
+                         */
+                        void *kaddr;
 
-                                kaddr = kmap_atomic(page, KM_USER0);
-                                memcpy(buffer, kaddr, PAGE_SIZE);
-                                kunmap_atomic(kaddr, KM_USER0);
-                                handle->buffer = buffer;
-                        } else {
-                                handle->buffer = page_address(page);
-                        }
+                        kaddr = kmap_atomic(page, KM_USER0);
+                        memcpy(buffer, kaddr, PAGE_SIZE);
+                        kunmap_atomic(kaddr, KM_USER0);
+                        handle->buffer = buffer;
+                } else {
+                        handle->buffer = page_address(page);
                 }
-                handle->prev = handle->cur;
-        }
-        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->cur_offset += count;
         }
-        handle->offset += count;
-        return count;
+        handle->cur++;
+        return PAGE_SIZE;
 }
 
 /**
@@ -2133,14 +2116,9 @@ static void *get_buffer(struct memory_bitmap *bm, struct chain_allocator *ca)
  *      snapshot_handle structure.  The structure gets updated and a pointer
  *      to it should be passed to this function every next time.
  *
- *      The @count parameter should contain the number of bytes the caller
- *      wants to write to the image.  It must not be zero.
- *
  *      On success the function returns a positive number.  Then, the caller
  *      is allowed to write up to the returned number of bytes to the memory
- *      location computed by the data_of() macro.  The number returned
- *      may be smaller than @count, but this only happens if the write would
- *      cross a page boundary otherwise.
+ *      location computed by the data_of() macro.
  *
  *      The function returns 0 to indicate the "end of file" condition,
  *      and a negative number is returned on error.  In such cases the
@@ -2148,16 +2126,18 @@ static void *get_buffer(struct memory_bitmap *bm, struct chain_allocator *ca)
  *      any more.
  */
 
-int snapshot_write_next(struct snapshot_handle *handle, size_t count)
+int snapshot_write_next(struct snapshot_handle *handle)
 {
         static struct chain_allocator ca;
         int error = 0;
 
         /* Check if we have already loaded the entire image */
-        if (handle->prev && handle->cur > nr_meta_pages + nr_copy_pages)
+        if (handle->cur > 1 && handle->cur > nr_meta_pages + nr_copy_pages)
                 return 0;
 
-        if (handle->offset == 0) {
+        handle->sync_read = 1;
+
+        if (!handle->cur) {
                 if (!buffer)
                         /* This makes the buffer be freed by swsusp_free() */
                         buffer = get_image_page(GFP_ATOMIC, PG_ANY);
@@ -2166,56 +2146,43 @@ int snapshot_write_next(struct snapshot_handle *handle, size_t count)
                         return -ENOMEM;
 
                 handle->buffer = buffer;
-        }
-        handle->sync_read = 1;
-        if (handle->prev < handle->cur) {
-                if (handle->prev == 0) {
-                        error = load_header(buffer);
-                        if (error)
-                                return error;
+        } else if (handle->cur == 1) {
+                error = load_header(buffer);
+                if (error)
+                        return error;
 
-                        error = memory_bm_create(&copy_bm, GFP_ATOMIC, PG_ANY);
-                        if (error)
-                                return error;
+                error = memory_bm_create(&copy_bm, GFP_ATOMIC, PG_ANY);
+                if (error)
+                        return error;
+
+        } else if (handle->cur <= nr_meta_pages + 1) {
+                error = unpack_orig_pfns(buffer, &copy_bm);
+                if (error)
+                        return error;
 
-                } else if (handle->prev <= nr_meta_pages) {
-                        error = unpack_orig_pfns(buffer, &copy_bm);
+                if (handle->cur == nr_meta_pages + 1) {
+                        error = prepare_image(&orig_bm, &copy_bm);
                         if (error)
                                 return error;
 
-                        if (handle->prev == nr_meta_pages) {
-                                error = prepare_image(&orig_bm, &copy_bm);
-                                if (error)
-                                        return error;
-
-                                chain_init(&ca, GFP_ATOMIC, PG_SAFE);
-                                memory_bm_position_reset(&orig_bm);
-                                restore_pblist = NULL;
-                                handle->buffer = get_buffer(&orig_bm, &ca);
-                                handle->sync_read = 0;
-                                if (IS_ERR(handle->buffer))
-                                        return PTR_ERR(handle->buffer);
-                        }
-                } else {
-                        copy_last_highmem_page();
+                        chain_init(&ca, GFP_ATOMIC, PG_SAFE);
+                        memory_bm_position_reset(&orig_bm);
+                        restore_pblist = NULL;
                         handle->buffer = get_buffer(&orig_bm, &ca);
+                        handle->sync_read = 0;
                         if (IS_ERR(handle->buffer))
                                 return PTR_ERR(handle->buffer);
-                        if (handle->buffer != buffer)
-                                handle->sync_read = 0;
                 }
-                handle->prev = handle->cur;
-        }
-        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->cur_offset += count;
+                copy_last_highmem_page();
+                handle->buffer = get_buffer(&orig_bm, &ca);
+                if (IS_ERR(handle->buffer))
+                        return PTR_ERR(handle->buffer);
+                if (handle->buffer != buffer)
+                        handle->sync_read = 0;
         }
-        handle->offset += count;
-        return count;
+        handle->cur++;
+        return PAGE_SIZE;
 }
 
 /**
@@ -2230,7 +2197,7 @@ void snapshot_write_finalize(struct snapshot_handle *handle)
 {
         copy_last_highmem_page();
         /* Free only if we have loaded the image entirely */
-        if (handle->prev && handle->cur > nr_meta_pages + nr_copy_pages) {
+        if (handle->cur > 1 && handle->cur > nr_meta_pages + nr_copy_pages) {
                 memory_bm_free(&orig_bm, PG_UNSAFE_CLEAR);
                 free_highmem_data();
         }
diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index 66824d71983a..b0bb21778391 100644
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -29,6 +29,40 @@
 
 #define SWSUSP_SIG      "S1SUSPEND"
 
+/*
+ *      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;
@@ -145,110 +179,24 @@ int swsusp_swap_in_use(void)
  */
 
 static unsigned short root_swap = 0xffff;
-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.
- *      @bio_chain: list of pending biod (for async reading)
- *
- *      Straight from the textbook - allocate and initialize the bio.
- *      If we're reading, make sure the page is marked as dirty.
- *      Then submit it and, if @bio_chain == NULL, wait.
- */
-static int submit(int rw, pgoff_t page_off, struct page *page,
-                        struct bio **bio_chain)
-{
-        const int bio_rw = rw | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG);
-        struct bio *bio;
-
-        bio = bio_alloc(__GFP_WAIT | __GFP_HIGH, 1);
-        bio->bi_sector = page_off * (PAGE_SIZE >> 9);
-        bio->bi_bdev = resume_bdev;
-        bio->bi_end_io = end_swap_bio_read;
-
-        if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
-                printk(KERN_ERR "PM: Adding page to bio failed at %ld\n",
-                        page_off);
-                bio_put(bio);
-                return -EFAULT;
-        }
-
-        lock_page(page);
-        bio_get(bio);
-
-        if (bio_chain == NULL) {
-                submit_bio(bio_rw, bio);
-                wait_on_page_locked(page);
-                if (rw == READ)
-                        bio_set_pages_dirty(bio);
-                bio_put(bio);
-        } else {
-                if (rw == READ)
-                        get_page(page); /* These pages are freed later */
-                bio->bi_private = *bio_chain;
-                *bio_chain = bio;
-                submit_bio(bio_rw, bio);
-        }
-        return 0;
-}
-
-static int bio_read_page(pgoff_t page_off, void *addr, struct bio **bio_chain)
-{
-        return submit(READ, page_off, virt_to_page(addr), bio_chain);
-}
-
-static int bio_write_page(pgoff_t page_off, void *addr, struct bio **bio_chain)
-{
-        return submit(WRITE, page_off, virt_to_page(addr), bio_chain);
-}
-
-static int wait_on_bio_chain(struct bio **bio_chain)
-{
-        struct bio *bio;
-        struct bio *next_bio;
-        int ret = 0;
-
-        if (bio_chain == NULL)
-                return 0;
-
-        bio = *bio_chain;
-        if (bio == NULL)
-                return 0;
-        while (bio) {
-                struct page *page;
-
-                next_bio = bio->bi_private;
-                page = bio->bi_io_vec[0].bv_page;
-                wait_on_page_locked(page);
-                if (!PageUptodate(page) || PageError(page))
-                        ret = -EIO;
-                put_page(page);
-                bio_put(bio);
-                bio = next_bio;
-        }
-        *bio_chain = NULL;
-        return ret;
-}
+struct block_device *hib_resume_bdev;
 
 /*
  * Saving part
  */
 
-static int mark_swapfiles(sector_t start, unsigned int flags)
+static int mark_swapfiles(struct swap_map_handle *handle, unsigned int flags)
 {
         int error;
 
-        bio_read_page(swsusp_resume_block, swsusp_header, NULL);
+        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 = start;
+                swsusp_header->image = handle->first_sector;
                 swsusp_header->flags = flags;
-                error = bio_write_page(swsusp_resume_block,
+                error = hib_bio_write_page(swsusp_resume_block,
                                         swsusp_header, NULL);
         } else {
                 printk(KERN_ERR "PM: Swap header not found!\n");
@@ -260,25 +208,26 @@ static int mark_swapfiles(sector_t start, unsigned int flags)
 /**
  *      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;
 
         res = swap_type_of(swsusp_resume_device, swsusp_resume_block,
-                        &resume_bdev);
+                        &hib_resume_bdev);
         if (res < 0)
                 return res;
 
         root_swap = res;
-        res = blkdev_get(resume_bdev, FMODE_WRITE);
+        res = blkdev_get(hib_resume_bdev, FMODE_WRITE);
         if (res)
                 return res;
 
-        res = set_blocksize(resume_bdev, PAGE_SIZE);
+        res = set_blocksize(hib_resume_bdev, PAGE_SIZE);
         if (res < 0)
-                blkdev_put(resume_bdev, FMODE_WRITE);
+                blkdev_put(hib_resume_bdev, FMODE_WRITE);
 
         return res;
 }
@@ -309,42 +258,9 @@ static int write_page(void *buf, sector_t offset, struct bio **bio_chain)
         } else {
                 src = buf;
         }
-        return bio_write_page(offset, src, bio_chain);
+        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(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;
-        unsigned int k;
-};
-
 static void release_swap_writer(struct swap_map_handle *handle)
 {
         if (handle->cur)
@@ -354,16 +270,33 @@ static void release_swap_writer(struct swap_map_handle *handle)
 
 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;
+        if (!handle->cur) {
+                ret = -ENOMEM;
+                goto err_close;
+        }
         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,
@@ -380,7 +313,7 @@ static int swap_write_page(struct swap_map_handle *handle, void *buf,
                 return error;
         handle->cur->entries[handle->k++] = offset;
         if (handle->k >= MAP_PAGE_ENTRIES) {
-                error = wait_on_bio_chain(bio_chain);
+                error = hib_wait_on_bio_chain(bio_chain);
                 if (error)
                         goto out;
                 offset = alloc_swapdev_block(root_swap);
@@ -406,6 +339,24 @@ static int flush_swap_writer(struct swap_map_handle *handle)
                 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
  */
@@ -431,7 +382,7 @@ static int save_image(struct swap_map_handle *handle,
         bio = NULL;
         do_gettimeofday(&start);
         while (1) {
-                ret = snapshot_read_next(snapshot, PAGE_SIZE);
+                ret = snapshot_read_next(snapshot);
                 if (ret <= 0)
                         break;
                 ret = swap_write_page(handle, data_of(*snapshot), &bio);
@@ -441,7 +392,7 @@ static int save_image(struct swap_map_handle *handle,
                         printk(KERN_CONT "\b\b\b\b%3d%%", nr_pages / m);
                 nr_pages++;
         }
-        err2 = wait_on_bio_chain(&bio);
+        err2 = hib_wait_on_bio_chain(&bio);
         do_gettimeofday(&stop);
         if (!ret)
                 ret = err2;
@@ -483,50 +434,34 @@ int swsusp_write(unsigned int flags)
         struct swap_map_handle handle;
         struct snapshot_handle snapshot;
         struct swsusp_info *header;
+        unsigned long pages;
         int error;
 
-        error = swsusp_swap_check();
+        pages = snapshot_get_image_size();
+        error = get_swap_writer(&handle);
         if (error) {
-                printk(KERN_ERR "PM: Cannot find swap device, try "
-                                "swapon -a.\n");
+                printk(KERN_ERR "PM: Cannot get swap writer\n");
                 return error;
         }
+        if (!enough_swap(pages)) {
+                printk(KERN_ERR "PM: Not enough free swap\n");
+                error = -ENOSPC;
+                goto out_finish;
+        }
         memset(&snapshot, 0, sizeof(struct snapshot_handle));
-        error = snapshot_read_next(&snapshot, PAGE_SIZE);
+        error = snapshot_read_next(&snapshot);
         if (error < PAGE_SIZE) {
                 if (error >= 0)
                         error = -EFAULT;
 
-                goto out;
+                goto out_finish;
         }
         header = (struct swsusp_info *)data_of(snapshot);
-        if (!enough_swap(header->pages)) {
-                printk(KERN_ERR "PM: Not enough free swap\n");
-                error = -ENOSPC;
-                goto out;
-        }
-        error = get_swap_writer(&handle);
-        if (!error) {
-                sector_t start = handle.cur_swap;
-
-                error = swap_write_page(&handle, header, NULL);
-                if (!error)
-                        error = save_image(&handle, &snapshot,
-                                        header->pages - 1);
-
-                if (!error) {
-                        flush_swap_writer(&handle);
-                        printk(KERN_INFO "PM: S");
-                        error = mark_swapfiles(start, flags);
-                        printk("|\n");
-                }
-        }
-        if (error)
-                free_all_swap_pages(root_swap);
-
-        release_swap_writer(&handle);
- out:
-        swsusp_close(FMODE_WRITE);
+        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;
 }
 
@@ -542,18 +477,21 @@ static void release_swap_reader(struct swap_map_handle *handle)
         handle->cur = NULL;
 }
 
-static int get_swap_reader(struct swap_map_handle *handle, sector_t start)
+static int get_swap_reader(struct swap_map_handle *handle,
+                unsigned int *flags_p)
 {
         int error;
 
-        if (!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_WAIT | __GFP_HIGH);
         if (!handle->cur)
                 return -ENOMEM;
 
-        error = bio_read_page(start, handle->cur, NULL);
+        error = hib_bio_read_page(swsusp_header->image, handle->cur, NULL);
         if (error) {
                 release_swap_reader(handle);
                 return error;
@@ -573,21 +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, bio_chain);
+        error = hib_bio_read_page(offset, buf, bio_chain);
         if (error)
                 return error;
         if (++handle->k >= MAP_PAGE_ENTRIES) {
-                error = wait_on_bio_chain(bio_chain);
+                error = hib_wait_on_bio_chain(bio_chain);
                 handle->k = 0;
                 offset = handle->cur->next_swap;
                 if (!offset)
                         release_swap_reader(handle);
                 else if (!error)
-                        error = bio_read_page(offset, handle->cur, NULL);
+                        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
@@ -615,21 +560,21 @@ static int load_image(struct swap_map_handle *handle,
         bio = NULL;
         do_gettimeofday(&start);
         for ( ; ; ) {
-                error = snapshot_write_next(snapshot, PAGE_SIZE);
+                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 = wait_on_bio_chain(&bio);
+                        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 = wait_on_bio_chain(&bio);
+        err2 = hib_wait_on_bio_chain(&bio);
         do_gettimeofday(&stop);
         if (!error)
                 error = err2;
@@ -657,20 +602,20 @@ int swsusp_read(unsigned int *flags_p)
         struct snapshot_handle snapshot;
         struct swsusp_info *header;
 
-        *flags_p = swsusp_header->flags;
-
         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, NULL);
         if (!error)
                 error = load_image(&handle, &snapshot, header->pages - 1);
-        release_swap_reader(&handle);
-
+        swap_reader_finish(&handle);
+end:
         if (!error)
                 pr_debug("PM: Image successfully loaded\n");
         else
@@ -686,11 +631,11 @@ 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);
+        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 = bio_read_page(swsusp_resume_block,
+                error = hib_bio_read_page(swsusp_resume_block,
                                         swsusp_header, NULL);
                 if (error)
                         goto put;
@@ -698,7 +643,7 @@ int swsusp_check(void)
                 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(swsusp_resume_block,
+                        error = hib_bio_write_page(swsusp_resume_block,
                                                 swsusp_header, NULL);
                 } else {
                         error = -EINVAL;
@@ -706,11 +651,11 @@ int swsusp_check(void)
 
 put:
                 if (error)
-                        blkdev_put(resume_bdev, FMODE_READ);
+                        blkdev_put(hib_resume_bdev, FMODE_READ);
                 else
                         pr_debug("PM: Signature found, resuming\n");
         } else {
-                error = PTR_ERR(resume_bdev);
+                error = PTR_ERR(hib_resume_bdev);
         }
 
         if (error)
@@ -725,12 +670,12 @@ put:
 
 void swsusp_close(fmode_t mode)
 {
-        if (IS_ERR(resume_bdev)) {
+        if (IS_ERR(hib_resume_bdev)) {
                 pr_debug("PM: Image device not initialised\n");
                 return;
         }
 
-        blkdev_put(resume_bdev, mode);
+        blkdev_put(hib_resume_bdev, mode);
 }
 
 static int swsusp_header_init(void)
diff --git a/kernel/power/user.c b/kernel/power/user.c
index a8c96212bc1b..e819e17877ca 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -151,6 +151,7 @@ static ssize_t snapshot_read(struct file *filp, char __user *buf,
 {
         struct snapshot_data *data;
         ssize_t res;
+        loff_t pg_offp = *offp & ~PAGE_MASK;
 
         mutex_lock(&pm_mutex);
 
@@ -159,14 +160,19 @@ static ssize_t snapshot_read(struct file *filp, char __user *buf,
                 res = -ENODATA;
                 goto Unlock;
         }
-        res = snapshot_read_next(&data->handle, count);
-        if (res > 0) {
-                if (copy_to_user(buf, data_of(data->handle), res))
-                        res = -EFAULT;
-                else
-                        *offp = data->handle.offset;
+        if (!pg_offp) { /* on page boundary? */
+                res = snapshot_read_next(&data->handle);
+                if (res <= 0)
+                        goto Unlock;
+        } else {
+                res = PAGE_SIZE - pg_offp;
         }
 
+        res = simple_read_from_buffer(buf, count, &pg_offp,
+                        data_of(data->handle), res);
+        if (res > 0)
+                *offp += res;
+
  Unlock:
         mutex_unlock(&pm_mutex);
 
@@ -178,18 +184,25 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf,
 {
         struct snapshot_data *data;
         ssize_t res;
+        loff_t pg_offp = *offp & ~PAGE_MASK;
 
         mutex_lock(&pm_mutex);
 
         data = filp->private_data;
-        res = snapshot_write_next(&data->handle, count);
-        if (res > 0) {
-                if (copy_from_user(data_of(data->handle), buf, res))
-                        res = -EFAULT;
-                else
-                        *offp = data->handle.offset;
+
+        if (!pg_offp) {
+                res = snapshot_write_next(&data->handle);
+                if (res <= 0)
+                        goto unlock;
+        } else {
+                res = PAGE_SIZE - pg_offp;
         }
 
+        res = simple_write_to_buffer(data_of(data->handle), res, &pg_offp,
+                        buf, count);
+        if (res > 0)
+                *offp += res;
+unlock:
         mutex_unlock(&pm_mutex);
 
         return res;