1 files changed, 17 insertions, 4 deletions

diff --git a/mm/swapfile.c b/mm/swapfile.c
index e47a21e64764..3074b02eaa09 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1328,6 +1328,13 @@ int page_swapcount(struct page *page)
         return count;
 }
 
+int __swap_count(struct swap_info_struct *si, swp_entry_t entry)
+{
+        pgoff_t offset = swp_offset(entry);
+
+        return swap_count(si->swap_map[offset]);
+}
+
 static int swap_swapcount(struct swap_info_struct *si, swp_entry_t entry)
 {
         int count = 0;
@@ -3169,6 +3176,9 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
         if (bdi_cap_stable_pages_required(inode_to_bdi(inode)))
                 p->flags |= SWP_STABLE_WRITES;
 
+        if (bdi_cap_synchronous_io(inode_to_bdi(inode)))
+                p->flags |= SWP_SYNCHRONOUS_IO;
+
         if (p->bdev && blk_queue_nonrot(bdev_get_queue(p->bdev))) {
                 int cpu;
                 unsigned long ci, nr_cluster;
@@ -3452,10 +3462,15 @@ int swapcache_prepare(swp_entry_t entry)
         return __swap_duplicate(entry, SWAP_HAS_CACHE);
 }
 
+struct swap_info_struct *swp_swap_info(swp_entry_t entry)
+{
+        return swap_info[swp_type(entry)];
+}
+
 struct swap_info_struct *page_swap_info(struct page *page)
 {
-        swp_entry_t swap = { .val = page_private(page) };
-        return swap_info[swp_type(swap)];
+        swp_entry_t entry = { .val = page_private(page) };
+        return swp_swap_info(entry);
 }
 
 /*
@@ -3463,7 +3478,6 @@ struct swap_info_struct *page_swap_info(struct page *page)
  */
 struct address_space *__page_file_mapping(struct page *page)
 {
-        VM_BUG_ON_PAGE(!PageSwapCache(page), page);
         return page_swap_info(page)->swap_file->f_mapping;
 }
 EXPORT_SYMBOL_GPL(__page_file_mapping);
@@ -3471,7 +3485,6 @@ EXPORT_SYMBOL_GPL(__page_file_mapping);
 pgoff_t __page_file_index(struct page *page)
 {
         swp_entry_t swap = { .val = page_private(page) };
-        VM_BUG_ON_PAGE(!PageSwapCache(page), page);
         return swp_offset(swap);
 }
 EXPORT_SYMBOL_GPL(__page_file_index);