4 files changed, 3 insertions, 120 deletions

diff --git a/include/linux/rmap.h b/include/linux/rmap.h
index 2d4c81a220db..bf97b0900014 100644
--- a/include/linux/rmap.h
+++ b/include/linux/rmap.h
@@ -91,7 +91,6 @@ static inline void page_dup_rmap(struct page *page)
  */
 int page_referenced(struct page *, int is_locked);
 int try_to_unmap(struct page *, int ignore_refs);
-void remove_from_swap(struct page *page);
 
 /*
  * Called from mm/filemap_xip.c to unmap empty zero page
diff --git a/mm/migrate.c b/mm/migrate.c
index 0a011e421bb4..81721a061d50 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -70,10 +70,6 @@ int isolate_lru_page(struct page *page, struct list_head *pagelist)
  */
 int migrate_prep(void)
 {
-        /* Must have swap device for migration */
-        if (nr_swap_pages <= 0)
-                return -ENODEV;
-
         /*
          * Clear the LRU lists so pages can be isolated.
          * Note that pages may be moved off the LRU after we have
@@ -246,52 +242,6 @@ out:
 }
 
 /*
- * swapout a single page
- * page is locked upon entry, unlocked on exit
- */
-static int swap_page(struct page *page)
-{
-        struct address_space *mapping = page_mapping(page);
-
-        if (page_mapped(page) && mapping)
-                if (try_to_unmap(page, 1) != SWAP_SUCCESS)
-                        goto unlock_retry;
-
-        if (PageDirty(page)) {
-                /* Page is dirty, try to write it out here */
-                switch(pageout(page, mapping)) {
-                case PAGE_KEEP:
-                case PAGE_ACTIVATE:
-                        goto unlock_retry;
-
-                case PAGE_SUCCESS:
-                        goto retry;
-
-                case PAGE_CLEAN:
-                        ; /* try to free the page below */
-                }
-        }
-
-        if (PagePrivate(page)) {
-                if (!try_to_release_page(page, GFP_KERNEL) ||
-                    (!mapping && page_count(page) == 1))
-                        goto unlock_retry;
-        }
-
-        if (remove_mapping(mapping, page)) {
-                /* Success */
-                unlock_page(page);
-                return 0;
-        }
-
-unlock_retry:
-        unlock_page(page);
-
-retry:
-        return -EAGAIN;
-}
-
-/*
  * Replace the page in the mapping.
  *
  * The number of remaining references must be:
@@ -517,8 +467,7 @@ static int fallback_migrate_page(struct address_space *mapping,
  * Two lists are passed to this function. The first list
  * contains the pages isolated from the LRU to be migrated.
  * The second list contains new pages that the pages isolated
- * can be moved to. If the second list is NULL then all
- * pages are swapped out.
+ * can be moved to.
  *
  * The function returns after 10 attempts or if no pages
  * are movable anymore because to has become empty
@@ -574,29 +523,11 @@ redo:
                  * Only wait on writeback if we have already done a pass where
                  * we we may have triggered writeouts for lots of pages.
                  */
-                if (pass > 0) {
+                if (pass > 0)
                         wait_on_page_writeback(page);
-                } else {
+                else
                         if (PageWriteback(page))
                                 goto unlock_page;
-                }
-
-                /*
-                 * Anonymous pages must have swap cache references otherwise
-                 * the information contained in the page maps cannot be
-                 * preserved.
-                 */
-                if (PageAnon(page) && !PageSwapCache(page)) {
-                        if (!add_to_swap(page, GFP_KERNEL)) {
-                                rc = -ENOMEM;
-                                goto unlock_page;
-                        }
-                }
-
-                if (!to) {
-                        rc = swap_page(page);
-                        goto next;
-                }
 
                 /*
                  * Establish swap ptes for anonymous pages or destroy pte
diff --git a/mm/rmap.c b/mm/rmap.c
index 3b8ce86daa3a..a53a10b93ecf 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -205,44 +205,6 @@ out:
         return anon_vma;
 }
 
-#ifdef CONFIG_MIGRATION
-/*
- * Remove an anonymous page from swap replacing the swap pte's
- * through real pte's pointing to valid pages and then releasing
- * the page from the swap cache.
- *
- * Must hold page lock on page and mmap_sem of one vma that contains
- * the page.
- */
-void remove_from_swap(struct page *page)
-{
-        struct anon_vma *anon_vma;
-        struct vm_area_struct *vma;
-        unsigned long mapping;
-
-        if (!PageSwapCache(page))
-                return;
-
-        mapping = (unsigned long)page->mapping;
-
-        if (!mapping || (mapping & PAGE_MAPPING_ANON) == 0)
-                return;
-
-        /*
-         * We hold the mmap_sem lock. So no need to call page_lock_anon_vma.
-         */
-        anon_vma = (struct anon_vma *) (mapping - PAGE_MAPPING_ANON);
-        spin_lock(&anon_vma->lock);
-
-        list_for_each_entry(vma, &anon_vma->head, anon_vma_node)
-                remove_vma_swap(vma, page);
-
-        spin_unlock(&anon_vma->lock);
-        delete_from_swap_cache(page);
-}
-EXPORT_SYMBOL(remove_from_swap);
-#endif
-
 /*
  * At what user virtual address is page expected in vma?
  */
diff --git a/mm/swapfile.c b/mm/swapfile.c
index e3b1362372c2..fbceed67a075 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -618,15 +618,6 @@ static int unuse_mm(struct mm_struct *mm,
         return 0;
 }
 
-#ifdef CONFIG_MIGRATION
-int remove_vma_swap(struct vm_area_struct *vma, struct page *page)
-{
-        swp_entry_t entry = { .val = page_private(page) };
-
-        return unuse_vma(vma, entry, page);
-}
-#endif
-
 /*
  * Scan swap_map from current position to next entry still in use.
  * Recycle to start on reaching the end, returning 0 when empty.