blkcg: mass rename of blkcg API

During the recent blkcg cleanup, most of blkcg API has changed to such
extent that mass renaming wouldn't cause any noticeable pain.  Take
the chance and cleanup the naming.

* Rename blkio_cgroup to blkcg.

* Drop blkio / blkiocg prefixes and consistently use blkcg.

* Rename blkio_group to blkcg_gq, which is consistent with io_cq but
  keep the blkg prefix / variable name.

* Rename policy method type and field names to signify they're dealing
  with policy data.

* Rename blkio_policy_type to blkcg_policy.

This patch doesn't cause any functional change.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 54 insertions, 55 deletions

diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
index b347aa0..a443b84 100644
--- a/block/blk-cgroup.h
+++ b/block/blk-cgroup.h
@@ -37,7 +37,7 @@ enum blkg_rwstat_type {
 	BLKG_RWSTAT_TOTAL = BLKG_RWSTAT_NR,
 };
 
-struct blkio_cgroup {
+struct blkcg {
 	struct cgroup_subsys_state	css;
 	spinlock_t			lock;
 	struct hlist_head		blkg_list;
@@ -45,7 +45,7 @@ struct blkio_cgroup {
 	/* for policies to test whether associated blkcg has changed */
 	uint64_t			id;
 
-	/* TODO: per-policy storage in blkio_cgroup */
+	/* TODO: per-policy storage in blkcg */
 	unsigned int			cfq_weight;	/* belongs to cfq */
 };
 
@@ -62,7 +62,7 @@ struct blkg_rwstat {
 /* per-blkg per-policy data */
 struct blkg_policy_data {
 	/* the blkg this per-policy data belongs to */
-	struct blkio_group		*blkg;
+	struct blkcg_gq			*blkg;
 
 	/* used during policy activation */
 	struct list_head		alloc_node;
@@ -71,12 +71,13 @@ struct blkg_policy_data {
 	char				pdata[] __aligned(__alignof__(unsigned long long));
 };
 
-struct blkio_group {
+/* association between a blk cgroup and a request queue */
+struct blkcg_gq {
 	/* Pointer to the associated request_queue */
 	struct request_queue		*q;
 	struct list_head		q_node;
 	struct hlist_node		blkcg_node;
-	struct blkio_cgroup		*blkcg;
+	struct blkcg			*blkcg;
 	/* reference count */
 	int				refcnt;
 
@@ -85,18 +86,18 @@ struct blkio_group {
 	struct rcu_head			rcu_head;
 };
 
-typedef void (blkio_init_group_fn)(struct blkio_group *blkg);
-typedef void (blkio_exit_group_fn)(struct blkio_group *blkg);
-typedef void (blkio_reset_group_stats_fn)(struct blkio_group *blkg);
+typedef void (blkcg_pol_init_pd_fn)(struct blkcg_gq *blkg);
+typedef void (blkcg_pol_exit_pd_fn)(struct blkcg_gq *blkg);
+typedef void (blkcg_pol_reset_pd_stats_fn)(struct blkcg_gq *blkg);
 
-struct blkio_policy_ops {
-	blkio_init_group_fn		*blkio_init_group_fn;
-	blkio_exit_group_fn		*blkio_exit_group_fn;
-	blkio_reset_group_stats_fn	*blkio_reset_group_stats_fn;
+struct blkcg_policy_ops {
+	blkcg_pol_init_pd_fn		*pd_init_fn;
+	blkcg_pol_exit_pd_fn		*pd_exit_fn;
+	blkcg_pol_reset_pd_stats_fn	*pd_reset_stats_fn;
 };
 
-struct blkio_policy_type {
-	struct blkio_policy_ops		ops;
+struct blkcg_policy {
+	struct blkcg_policy_ops		ops;
 	int				plid;
 	/* policy specific private data size */
 	size_t				pdata_size;
@@ -104,29 +105,28 @@ struct blkio_policy_type {
 	struct cftype			*cftypes;
 };
 
-extern struct blkio_cgroup blkio_root_cgroup;
+extern struct blkcg blkcg_root;
 
-struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup);
-struct blkio_cgroup *bio_blkio_cgroup(struct bio *bio);
-struct blkio_group *blkg_lookup(struct blkio_cgroup *blkcg,
-				struct request_queue *q);
-struct blkio_group *blkg_lookup_create(struct blkio_cgroup *blkcg,
-				       struct request_queue *q);
+struct blkcg *cgroup_to_blkcg(struct cgroup *cgroup);
+struct blkcg *bio_blkcg(struct bio *bio);
+struct blkcg_gq *blkg_lookup(struct blkcg *blkcg, struct request_queue *q);
+struct blkcg_gq *blkg_lookup_create(struct blkcg *blkcg,
+				    struct request_queue *q);
 int blkcg_init_queue(struct request_queue *q);
 void blkcg_drain_queue(struct request_queue *q);
 void blkcg_exit_queue(struct request_queue *q);
 
 /* Blkio controller policy registration */
-int blkio_policy_register(struct blkio_policy_type *);
-void blkio_policy_unregister(struct blkio_policy_type *);
+int blkcg_policy_register(struct blkcg_policy *pol);
+void blkcg_policy_unregister(struct blkcg_policy *pol);
 int blkcg_activate_policy(struct request_queue *q,
-			  const struct blkio_policy_type *pol);
+			  const struct blkcg_policy *pol);
 void blkcg_deactivate_policy(struct request_queue *q,
-			     const struct blkio_policy_type *pol);
+			     const struct blkcg_policy *pol);
 
-void blkcg_print_blkgs(struct seq_file *sf, struct blkio_cgroup *blkcg,
+void blkcg_print_blkgs(struct seq_file *sf, struct blkcg *blkcg,
 		       u64 (*prfill)(struct seq_file *, void *, int),
-		       const struct blkio_policy_type *pol, int data,
+		       const struct blkcg_policy *pol, int data,
 		       bool show_total);
 u64 __blkg_prfill_u64(struct seq_file *sf, void *pdata, u64 v);
 u64 __blkg_prfill_rwstat(struct seq_file *sf, void *pdata,
@@ -136,13 +136,12 @@ u64 blkg_prfill_rwstat(struct seq_file *sf, void *pdata, int off);
 
 struct blkg_conf_ctx {
 	struct gendisk			*disk;
-	struct blkio_group		*blkg;
+	struct blkcg_gq			*blkg;
 	u64				v;
 };
 
-int blkg_conf_prep(struct blkio_cgroup *blkcg,
-		   const struct blkio_policy_type *pol, const char *input,
-		   struct blkg_conf_ctx *ctx);
+int blkg_conf_prep(struct blkcg *blkcg, const struct blkcg_policy *pol,
+		   const char *input, struct blkg_conf_ctx *ctx);
 void blkg_conf_finish(struct blkg_conf_ctx *ctx);
 
 
@@ -153,8 +152,8 @@ void blkg_conf_finish(struct blkg_conf_ctx *ctx);
  *
  * Return pointer to private data associated with the @blkg-@pol pair.
  */
-static inline void *blkg_to_pdata(struct blkio_group *blkg,
-			      struct blkio_policy_type *pol)
+static inline void *blkg_to_pdata(struct blkcg_gq *blkg,
+				  struct blkcg_policy *pol)
 {
 	return blkg ? blkg->pd[pol->plid]->pdata : NULL;
 }
@@ -165,7 +164,7 @@ static inline void *blkg_to_pdata(struct blkio_group *blkg,
  *
  * @pdata is policy private data.  Determine the blkg it's associated with.
  */
-static inline struct blkio_group *pdata_to_blkg(void *pdata)
+static inline struct blkcg_gq *pdata_to_blkg(void *pdata)
 {
 	if (pdata) {
 		struct blkg_policy_data *pd =
@@ -183,7 +182,7 @@ static inline struct blkio_group *pdata_to_blkg(void *pdata)
  *
  * Format the path of the cgroup of @blkg into @buf.
  */
-static inline int blkg_path(struct blkio_group *blkg, char *buf, int buflen)
+static inline int blkg_path(struct blkcg_gq *blkg, char *buf, int buflen)
 {
 	int ret;
 
@@ -201,14 +200,14 @@ static inline int blkg_path(struct blkio_group *blkg, char *buf, int buflen)
  *
  * The caller should be holding queue_lock and an existing reference.
  */
-static inline void blkg_get(struct blkio_group *blkg)
+static inline void blkg_get(struct blkcg_gq *blkg)
 {
 	lockdep_assert_held(blkg->q->queue_lock);
 	WARN_ON_ONCE(!blkg->refcnt);
 	blkg->refcnt++;
 }
 
-void __blkg_release(struct blkio_group *blkg);
+void __blkg_release(struct blkcg_gq *blkg);
 
 /**
  * blkg_put - put a blkg reference
@@ -216,7 +215,7 @@ void __blkg_release(struct blkio_group *blkg);
  *
  * The caller should be holding queue_lock.
  */
-static inline void blkg_put(struct blkio_group *blkg)
+static inline void blkg_put(struct blkcg_gq *blkg)
 {
 	lockdep_assert_held(blkg->q->queue_lock);
 	WARN_ON_ONCE(blkg->refcnt <= 0);
@@ -343,32 +342,32 @@ static inline void blkg_rwstat_reset(struct blkg_rwstat *rwstat)
 
 struct cgroup;
 
-struct blkio_group {
+struct blkcg_gq {
 };
 
-struct blkio_policy_type {
+struct blkcg_policy {
 };
 
-static inline struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup) { return NULL; }
-static inline struct blkio_cgroup *bio_blkio_cgroup(struct bio *bio) { return NULL; }
-static inline struct blkio_group *blkg_lookup(struct blkio_cgroup *blkcg, void *key) { return NULL; }
+static inline struct blkcg *cgroup_to_blkcg(struct cgroup *cgroup) { return NULL; }
+static inline struct blkcg *bio_blkcg(struct bio *bio) { return NULL; }
+static inline struct blkcg_gq *blkg_lookup(struct blkcg *blkcg, void *key) { return NULL; }
 static inline int blkcg_init_queue(struct request_queue *q) { return 0; }
 static inline void blkcg_drain_queue(struct request_queue *q) { }
 static inline void blkcg_exit_queue(struct request_queue *q) { }
-static inline int blkio_policy_register(struct blkio_policy_type *blkiop) { return 0; }
-static inline void blkio_policy_unregister(struct blkio_policy_type *blkiop) { }
+static inline int blkcg_policy_register(struct blkcg_policy *pol) { return 0; }
+static inline void blkcg_policy_unregister(struct blkcg_policy *pol) { }
 static inline int blkcg_activate_policy(struct request_queue *q,
-					const struct blkio_policy_type *pol) { return 0; }
+					const struct blkcg_policy *pol) { return 0; }
 static inline void blkcg_deactivate_policy(struct request_queue *q,
-					   const struct blkio_policy_type *pol) { }
-
-static inline void *blkg_to_pdata(struct blkio_group *blkg,
-				struct blkio_policy_type *pol) { return NULL; }
-static inline struct blkio_group *pdata_to_blkg(void *pdata,
-				struct blkio_policy_type *pol) { return NULL; }
-static inline char *blkg_path(struct blkio_group *blkg) { return NULL; }
-static inline void blkg_get(struct blkio_group *blkg) { }
-static inline void blkg_put(struct blkio_group *blkg) { }
+					   const struct blkcg_policy *pol) { }
+
+static inline void *blkg_to_pdata(struct blkcg_gq *blkg,
+				  struct blkcg_policy *pol) { return NULL; }
+static inline struct blkcg_gq *pdata_to_blkg(void *pdata,
+				  struct blkcg_policy *pol) { return NULL; }
+static inline char *blkg_path(struct blkcg_gq *blkg) { return NULL; }
+static inline void blkg_get(struct blkcg_gq *blkg) { }
+static inline void blkg_put(struct blkcg_gq *blkg) { }
 
 #endif	/* CONFIG_BLK_CGROUP */
 #endif	/* _BLK_CGROUP_H */