Merge branch 'perf/urgent' into perf/core, to pick up fixes

[linux-2.6-microblaze.git] / mm / vmscan.c

diff --git a/mm/vmscan.c b/mm/vmscan.c
index bd620b6..eb3dd37 100644 (file)
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -46,6 +46,7 @@
 #include <linux/oom.h>
 #include <linux/prefetch.h>
 #include <linux/printk.h>
+#include <linux/dax.h>
 
 #include <asm/tlbflush.h>
 #include <asm/div64.h>
@@ -671,9 +672,15 @@ static int __remove_mapping(struct address_space *mapping, struct page *page,
                 * inode reclaim needs to empty out the radix tree or
                 * the nodes are lost.  Don't plant shadows behind its
                 * back.
+                *
+                * We also don't store shadows for DAX mappings because the
+                * only page cache pages found in these are zero pages
+                * covering holes, and because we don't want to mix DAX
+                * exceptional entries and shadow exceptional entries in the
+                * same page_tree.
                 */
                if (reclaimed && page_is_file_cache(page) &&
-                   !mapping_exiting(mapping))
+                   !mapping_exiting(mapping) && !dax_mapping(mapping))
                        shadow = workingset_eviction(mapping, page);
                __delete_from_page_cache(page, shadow, memcg);
                spin_unlock_irqrestore(&mapping->tree_lock, flags);