1 files changed, 26 insertions, 12 deletions

diff --git a/mm/swapfile.c b/mm/swapfile.c
index f315131db006..2bfacbac0f4c 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -427,34 +427,48 @@ void free_swap_and_cache(swp_entry_t entry)
 
 #ifdef CONFIG_SOFTWARE_SUSPEND
 /*
- * Find the swap type that corresponds to given device (if any)
+ * Find the swap type that corresponds to given device (if any).
  *
- * This is needed for software suspend and is done in such a way that inode
- * aliasing is allowed.
+ * @offset - number of the PAGE_SIZE-sized block of the device, starting
+ * from 0, in which the swap header is expected to be located.
+ *
+ * This is needed for the suspend to disk (aka swsusp).
  */
-int swap_type_of(dev_t device)
+int swap_type_of(dev_t device, sector_t offset)
 {
+        struct block_device *bdev = NULL;
         int i;
 
+        if (device)
+                bdev = bdget(device);
+
         spin_lock(&swap_lock);
         for (i = 0; i < nr_swapfiles; i++) {
-                struct inode *inode;
+                struct swap_info_struct *sis = swap_info + i;
 
-                if (!(swap_info[i].flags & SWP_WRITEOK))
+                if (!(sis->flags & SWP_WRITEOK))
                         continue;
 
-                if (!device) {
+                if (!bdev) {
                         spin_unlock(&swap_lock);
                         return i;
                 }
-                inode = swap_info[i].swap_file->f_dentry->d_inode;
-                if (S_ISBLK(inode->i_mode) &&
-                    device == MKDEV(imajor(inode), iminor(inode))) {
-                        spin_unlock(&swap_lock);
-                        return i;
+                if (bdev == sis->bdev) {
+                        struct swap_extent *se;
+
+                        se = list_entry(sis->extent_list.next,
+                                        struct swap_extent, list);
+                        if (se->start_block == offset) {
+                                spin_unlock(&swap_lock);
+                                bdput(bdev);
+                                return i;
+                        }
                 }
         }
         spin_unlock(&swap_lock);
+        if (bdev)
+                bdput(bdev);
+
         return -ENODEV;
 }