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>

1 files changed, 1 insertions, 4 deletions

diff --git a/fs/stack.c b/fs/stack.c
index 4a6f7f4..b4f2ab48 100644
--- a/fs/stack.c
+++ b/fs/stack.c
@@ -29,10 +29,7 @@ void fsstack_copy_inode_size(struct inode *dst, struct inode *src)
 	 *
 	 * We don't actually know what locking is used at the lower level;
 	 * but if it's a filesystem that supports quotas, it will be using
-	 * i_lock as in inode_add_bytes().  tmpfs uses other locking, and
-	 * its 32-bit is (just) able to exceed 2TB i_size with the aid of
-	 * holes; but its i_blocks cannot carry into the upper long without
-	 * almost 2TB swap - let's ignore that case.
+	 * i_lock as in inode_add_bytes().
 	 */
 	if (sizeof(i_blocks) > sizeof(long))
 		spin_lock(&src->i_lock);