switch ->is_partially_uptodate() to saner arguments

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h
index d77797a..c40302f 100644
--- a/include/linux/buffer_head.h
+++ b/include/linux/buffer_head.h
@@ -210,8 +210,8 @@
 int block_write_full_page_endio(struct page *page, get_block_t *get_block,
 			struct writeback_control *wbc, bh_end_io_t *handler);
 int block_read_full_page(struct page*, get_block_t*);
-int block_is_partially_uptodate(struct page *page, read_descriptor_t *desc,
-				unsigned long from);
+int block_is_partially_uptodate(struct page *page, unsigned long from,
+				unsigned long count);
 int block_write_begin(struct address_space *mapping, loff_t pos, unsigned len,
 		unsigned flags, struct page **pagep, get_block_t *get_block);
 int __block_write_begin(struct page *page, loff_t pos, unsigned len,
diff --git a/include/linux/fs.h b/include/linux/fs.h
index db181b5..ddfff2e 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -385,7 +385,7 @@
 	int (*migratepage) (struct address_space *,
 			struct page *, struct page *, enum migrate_mode);
 	int (*launder_page) (struct page *);
-	int (*is_partially_uptodate) (struct page *, read_descriptor_t *,
+	int (*is_partially_uptodate) (struct page *, unsigned long,
 					unsigned long);
 	void (*is_dirty_writeback) (struct page *, bool *, bool *);
 	int (*error_remove_page)(struct address_space *, struct page *);