[PATCH] page_add_file_rmap(): remove BUG_ON()s

Remove two early-development BUG_ONs from page_add_file_rmap.

The pfn_valid test (originally useful for checking that nobody passed an
artificial struct page) comes too late, since we already have the struct
page.

The PageAnon test (useful when anon was first distinguished from file rmap)
prevents ->nopage implementations from reusing ->mapping, which would
otherwise be available.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/mm/rmap.c b/mm/rmap.c
index d8ce5ff6145492469a3b81640946fca58d7e8002..67f0e20b101ffbba34a8a3568374e14ab1a2bee8 100644 (file)
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -537,9 +537,6 @@ void page_add_new_anon_rmap(struct page *page,
  */
 void page_add_file_rmap(struct page *page)
 {
-       BUG_ON(PageAnon(page));
-       BUG_ON(!pfn_valid(page_to_pfn(page)));
-
        if (atomic_inc_and_test(&page->_mapcount))
                __inc_page_state(nr_mapped);
 }