1 files changed, 58 insertions, 0 deletions

diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
new file mode 100644
index 000000000000..ba5703f69b42
--- /dev/null
+++ b/block/blk-cgroup.h
@@ -0,0 +1,58 @@
+#ifndef _BLK_CGROUP_H
+#define _BLK_CGROUP_H
+/*
+ * Common Block IO controller cgroup interface
+ *
+ * Based on ideas and code from CFQ, CFS and BFQ:
+ * Copyright (C) 2003 Jens Axboe <axboe@kernel.dk>
+ *
+ * Copyright (C) 2008 Fabio Checconi <fabio@gandalf.sssup.it>
+ *                    Paolo Valente <paolo.valente@unimore.it>
+ *
+ * Copyright (C) 2009 Vivek Goyal <vgoyal@redhat.com>
+ *                    Nauman Rafique <nauman@google.com>
+ */
+
+#include <linux/cgroup.h>
+
+struct blkio_cgroup {
+        struct cgroup_subsys_state css;
+        unsigned int weight;
+        spinlock_t lock;
+        struct hlist_head blkg_list;
+};
+
+struct blkio_group {
+        /* An rcu protected unique identifier for the group */
+        void *key;
+        struct hlist_node blkcg_node;
+};
+
+#define BLKIO_WEIGHT_MIN        100
+#define BLKIO_WEIGHT_MAX        1000
+#define BLKIO_WEIGHT_DEFAULT    500
+
+#ifdef CONFIG_BLK_CGROUP
+extern struct blkio_cgroup blkio_root_cgroup;
+extern struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup);
+extern void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
+                                struct blkio_group *blkg, void *key);
+extern int blkiocg_del_blkio_group(struct blkio_group *blkg);
+extern struct blkio_group *blkiocg_lookup_group(struct blkio_cgroup *blkcg,
+                                                void *key);
+#else
+static inline struct blkio_cgroup *
+cgroup_to_blkio_cgroup(struct cgroup *cgroup) { return NULL; }
+
+static inline void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
+                        struct blkio_group *blkg, void *key)
+{
+}
+
+static inline int
+blkiocg_del_blkio_group(struct blkio_group *blkg) { return 0; }
+
+static inline struct blkio_group *
+blkiocg_lookup_group(struct blkio_cgroup *blkcg, void *key) { return NULL; }
+#endif
+#endif /* _BLK_CGROUP_H */