writeback: don't embed root bdi_writeback_congested in bdi_writeback

[cascardo/linux.git] / include / linux / backing-dev.h

diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h
index 0e6d482..0fe9df9 100644 (file)
--- a/include/linux/backing-dev.h
+++ b/include/linux/backing-dev.h
@@ -15,6 +15,7 @@
 #include <linux/writeback.h>
 #include <linux/blk-cgroup.h>
 #include <linux/backing-dev-defs.h>
+#include <linux/slab.h>
 
 int __must_check bdi_init(struct backing_dev_info *bdi);
 void bdi_destroy(struct backing_dev_info *bdi);
@@ -465,11 +466,14 @@ static inline bool inode_cgwb_enabled(struct inode *inode)
 static inline struct bdi_writeback_congested *
 wb_congested_get_create(struct backing_dev_info *bdi, int blkcg_id, gfp_t gfp)
 {
-       return bdi->wb.congested;
+       atomic_inc(&bdi->wb_congested->refcnt);
+       return bdi->wb_congested;
 }
 
 static inline void wb_congested_put(struct bdi_writeback_congested *congested)
 {
+       if (atomic_dec_and_test(&congested->refcnt))
+               kfree(congested);
 }
 
 static inline struct bdi_writeback *wb_find_current(struct backing_dev_info *bdi)