3 files changed, 23 insertions, 6 deletions

diff --git a/kernel/power/power.h b/kernel/power/power.h
index 2093c3a9a994..23c17031ed21 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -128,6 +128,7 @@ struct snapshot_handle {
 #define data_of(handle) ((handle).buffer + (handle).buf_offset)
 
 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 void snapshot_write_finalize(struct snapshot_handle *handle);
@@ -158,7 +159,8 @@ struct resume_swap_area {
 #define SNAPSHOT_PMOPS                  _IOW(SNAPSHOT_IOC_MAGIC, 12, unsigned int)
 #define SNAPSHOT_SET_SWAP_AREA          _IOW(SNAPSHOT_IOC_MAGIC, 13, \
                                                         struct resume_swap_area)
-#define SNAPSHOT_IOC_MAXNR      13
+#define SNAPSHOT_GET_IMAGE_SIZE         _IOR(SNAPSHOT_IOC_MAGIC, 14, loff_t)
+#define SNAPSHOT_IOC_MAXNR      14
 
 #define PMOPS_PREPARE   1
 #define PMOPS_ENTER     2
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 78039b477d2b..c5ce0f34a5d4 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -1264,12 +1264,17 @@ static char *check_image_kernel(struct swsusp_info *info)
 }
 #endif /* CONFIG_ARCH_HIBERNATION_HEADER */
 
+unsigned long snapshot_get_image_size(void)
+{
+        return nr_copy_pages + nr_meta_pages + 1;
+}
+
 static int init_header(struct swsusp_info *info)
 {
         memset(info, 0, sizeof(struct swsusp_info));
         info->num_physpages = num_physpages;
         info->image_pages = nr_copy_pages;
-        info->pages = nr_copy_pages + nr_meta_pages + 1;
+        info->pages = snapshot_get_image_size();
         info->size = info->pages;
         info->size <<= PAGE_SHIFT;
         return init_header_complete(info);
diff --git a/kernel/power/user.c b/kernel/power/user.c
index 5bd321bcbb75..88aac26e598a 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -133,7 +133,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
 {
         int error = 0;
         struct snapshot_data *data;
-        loff_t avail;
+        loff_t size;
         sector_t offset;
 
         if (_IOC_TYPE(cmd) != SNAPSHOT_IOC_MAGIC)
@@ -210,10 +210,20 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
                 image_size = arg;
                 break;
 
+        case SNAPSHOT_GET_IMAGE_SIZE:
+                if (!data->ready) {
+                        error = -ENODATA;
+                        break;
+                }
+                size = snapshot_get_image_size();
+                size <<= PAGE_SHIFT;
+                error = put_user(size, (loff_t __user *)arg);
+                break;
+
         case SNAPSHOT_AVAIL_SWAP:
-                avail = count_swap_pages(data->swap, 1);
-                avail <<= PAGE_SHIFT;
-                error = put_user(avail, (loff_t __user *)arg);
+                size = count_swap_pages(data->swap, 1);
+                size <<= PAGE_SHIFT;
+                error = put_user(size, (loff_t __user *)arg);
                 break;
 
         case SNAPSHOT_GET_SWAP_PAGE: