mm: Convert page-writeback to XArray

Includes moving mapping_tagged() to fs.h as a static inline, and
changing it to return bool.

Signed-off-by: Matthew Wilcox <willy@infradead.org>

1 files changed, 10 insertions, 7 deletions

diff --git a/include/linux/fs.h b/include/linux/fs.h
index d126cad0f621..e10278e4db66 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -483,15 +483,18 @@ struct block_device {
         struct mutex            bd_fsfreeze_mutex;
 } __randomize_layout;
 
+/* XArray tags, for tagging dirty and writeback pages in the pagecache. */
+#define PAGECACHE_TAG_DIRTY     XA_MARK_0
+#define PAGECACHE_TAG_WRITEBACK XA_MARK_1
+#define PAGECACHE_TAG_TOWRITE   XA_MARK_2
+
 /*
- * Radix-tree tags, for tagging dirty and writeback pages within the pagecache
- * radix trees
+ * Returns true if any of the pages in the mapping are marked with the tag.
  */
-#define PAGECACHE_TAG_DIRTY     0
-#define PAGECACHE_TAG_WRITEBACK 1
-#define PAGECACHE_TAG_TOWRITE   2
-
-int mapping_tagged(struct address_space *mapping, int tag);
+static inline bool mapping_tagged(struct address_space *mapping, xa_mark_t tag)
+{
+        return xa_marked(&mapping->i_pages, tag);
+}
 
 static inline void i_mmap_lock_write(struct address_space *mapping)
 {