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Diffstat (limited to 'kernel/power/swap.c')
-rw-r--r--kernel/power/swap.c333
1 files changed, 139 insertions, 194 deletions
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)