1 files changed, 11 insertions, 0 deletions

diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index d3ca2b3ee176..41733c5dc820 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -221,12 +221,23 @@ static ssize_t max_ratio_store(struct device *dev,
 }
 BDI_SHOW(max_ratio, bdi->max_ratio)
 
+static ssize_t stable_pages_required_show(struct device *dev,
+                                          struct device_attribute *attr,
+                                          char *page)
+{
+        struct backing_dev_info *bdi = dev_get_drvdata(dev);
+
+        return snprintf(page, PAGE_SIZE-1, "%d\n",
+                        bdi_cap_stable_pages_required(bdi) ? 1 : 0);
+}
+
 #define __ATTR_RW(attr) __ATTR(attr, 0644, attr##_show, attr##_store)
 
 static struct device_attribute bdi_dev_attrs[] = {
         __ATTR_RW(read_ahead_kb),
         __ATTR_RW(min_ratio),
         __ATTR_RW(max_ratio),
+        __ATTR_RO(stable_pages_required),
         __ATTR_NULL,
 };