lib: radix-tree: update callback for changing leaf nodes
Support handing __radix_tree_replace() a callback that gets invoked for
all leaf nodes that change or get freed as a result of the slot
replacement, to assist users tracking nodes with node->private_list.
This prepares for putting page cache shadow entries into the radix tree
root again and drastically simplifying the shadow tracking.
Link: http://lkml.kernel.org/r/20161117193134.GD23430@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Suggested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <mawilcox@linuxonhyperv.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/dax.c b/fs/dax.c
index 85930c2..6916ed3 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -649,7 +649,8 @@ static void *dax_insert_mapping_entry(struct address_space *mapping,
ret = __radix_tree_lookup(page_tree, index, &node, &slot);
WARN_ON_ONCE(ret != entry);
- __radix_tree_replace(page_tree, node, slot, new_entry);
+ __radix_tree_replace(page_tree, node, slot,
+ new_entry, NULL, NULL);
}
if (vmf->flags & FAULT_FLAG_WRITE)
radix_tree_tag_set(page_tree, index, PAGECACHE_TAG_DIRTY);