[PATCH] Swapless page migration: rip out swap based logic

Rip the page migration logic out.

Remove all code that has to do with swapping during page migration.

This also guts the ability to migrate pages to swap.  No one used that so lets
let it go for good.

Page migration should be a bit broken after this patch.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 0 insertions, 38 deletions

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?
  */