3 files changed, 15 insertions, 3 deletions

diff --git a/mm/highmem.c b/mm/highmem.c
index 57d82c6250c3..d517cd16a6eb 100644
--- a/mm/highmem.c
+++ b/mm/highmem.c
@@ -94,6 +94,18 @@ static DECLARE_WAIT_QUEUE_HEAD(pkmap_map_wait);
                 do { spin_unlock(&kmap_lock); (void)(flags); } while (0)
 #endif
 
+struct page *kmap_to_page(void *vaddr)
+{
+        unsigned long addr = (unsigned long)vaddr;
+
+        if (addr >= PKMAP_ADDR(0) && addr <= PKMAP_ADDR(LAST_PKMAP)) {
+                int i = (addr - PKMAP_ADDR(0)) >> PAGE_SHIFT;
+                return pte_page(pkmap_page_table[i]);
+        }
+
+        return virt_to_page(addr);
+}
+
 static void flush_all_zero_pkmaps(void)
 {
         int i;
diff --git a/mm/page_io.c b/mm/page_io.c
index 4a379629e31f..78eee32ee486 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -205,7 +205,7 @@ int swap_writepage(struct page *page, struct writeback_control *wbc)
                 struct file *swap_file = sis->swap_file;
                 struct address_space *mapping = swap_file->f_mapping;
                 struct iovec iov = {
-                        .iov_base = page_address(page),
+                        .iov_base = kmap(page),
                         .iov_len  = PAGE_SIZE,
                 };
 
@@ -218,6 +218,7 @@ int swap_writepage(struct page *page, struct writeback_control *wbc)
                 ret = mapping->a_ops->direct_IO(KERNEL_WRITE,
                                                 &kiocb, &iov,
                                                 kiocb.ki_pos, 1);
+                kunmap(page);
                 if (ret == PAGE_SIZE) {
                         count_vm_event(PSWPOUT);
                         ret = 0;
diff --git a/mm/swap.c b/mm/swap.c
index 7d7f80c8044a..77825883298f 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -258,8 +258,7 @@ int get_kernel_pages(const struct kvec *kiov, int nr_segs, int write,
                 if (WARN_ON(kiov[seg].iov_len != PAGE_SIZE))
                         return seg;
 
-                /* virt_to_page sanity checks the PFN */
-                pages[seg] = virt_to_page(kiov[seg].iov_base);
+                pages[seg] = kmap_to_page(kiov[seg].iov_base);
                 page_cache_get(pages[seg]);
         }