mm: a few small updates for radix-swap
Remove PageSwapBacked (!page_is_file_cache) cases from
add_to_page_cache_locked() and add_to_page_cache_lru(): those pages now
go through shmem_add_to_page_cache().
Remove a comment on maximum tmpfs size from fsstack_copy_inode_size(),
and add a comment on swap entries to invalidate_mapping_pages().
And mincore_page() uses find_get_page() on what might be shmem or a
tmpfs file: allow for a radix_tree_exceptional_entry(), and proceed to
find_get_page() on swapper_space if so (oh, swapper_space needs #ifdef).
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/mincore.c b/mm/mincore.c
index a4e6b9d..733f182 100644
--- a/mm/mincore.c
+++ b/mm/mincore.c
@@ -69,12 +69,14 @@
* file will not get a swp_entry_t in its pte, but rather it is like
* any other file mapping (ie. marked !present and faulted in with
* tmpfs's .fault). So swapped out tmpfs mappings are tested here.
- *
- * However when tmpfs moves the page from pagecache and into swapcache,
- * it is still in core, but the find_get_page below won't find it.
- * No big deal, but make a note of it.
*/
page = find_get_page(mapping, pgoff);
+#ifdef CONFIG_SWAP
+ if (radix_tree_exceptional_entry(page)) {
+ swp_entry_t swap = radix_to_swp_entry(page);
+ page = find_get_page(&swapper_space, swap.val);
+ }
+#endif
if (page) {
present = PageUptodate(page);
page_cache_release(page);