cgroups: implement "driver" and "driver_version"

src/lxc/cgroups/cgfsng.c

@@ -2800,12 +2800,12 @@ static struct cgroup_ops cgfsng_ops = {
 	.set = cgfsng_set,
 	.unfreeze = cgfsng_unfreeze,
 	.setup_limits = cgfsng_setup_limits,
-	.name = "cgroupfs-ng",
+	.driver = "cgfsng",
+	.version = "1.0.0",
 	.attach = cgfsng_attach,
 	.chown = cgfsng_chown,
 	.mount_cgroup = cgfsng_mount,
 	.nrtasks = cgfsng_nrtasks,
-	.driver = CGFSNG,
 
 	/* unsupported */
 	.create_legacy = NULL,

src/lxc/cgroups/cgroup.c

@@ -39,14 +39,14 @@ extern struct cgroup_ops *cgfsng_ops_init(void);
 __attribute__((constructor)) void cgroup_ops_init(void)
 {
 	if (ops) {
-		INFO("cgroup driver %s", ops->name);
+		INFO("Running with %s in version %s", ops->driver, ops->version);
 		return;
 	}
 
 	DEBUG("cgroup_init");
 	ops = cgfsng_ops_init();
 	if (ops)
-		INFO("Initialized cgroup driver %s", ops->name);
+		INFO("Initialized cgroup driver %s", ops->driver);
 }
 
 bool cgroup_init(struct lxc_handler *handler)
@@ -57,7 +57,7 @@ bool cgroup_init(struct lxc_handler *handler)
 	}
 
 	if (ops) {
-		INFO("cgroup driver %s initing for %s", ops->name, handler->name);
+		INFO("cgroup driver %s initing for %s", ops->driver, handler->name);
 		handler->cgroup_data = ops->init(handler);
 	}
 
@@ -170,7 +170,7 @@ int cgroup_nrtasks(struct lxc_handler *handler)
 		if (ops->nrtasks)
 			return ops->nrtasks(handler->cgroup_data);
 		else
-			WARN("cgroup driver \"%s\" doesn't implement nrtasks", ops->name);
+			WARN("cgroup driver \"%s\" doesn't implement nrtasks", ops->driver);
 	}
 
 	return -1;
@@ -208,11 +208,6 @@ void cgroup_disconnect(void)
 		ops->disconnect();
 }
 
-cgroup_driver_t cgroup_driver(void)
-{
-	return ops->driver;
-}
-
 #define INIT_SCOPE "/init.scope"
 void prune_init_scope(char *cg)
 {

src/lxc/cgroups/cgroup.h

@@ -39,14 +39,9 @@ typedef enum {
         CGROUP_LAYOUT_UNIFIED =  2,
 } cgroup_layout_t;
 
-typedef enum {
-	CGFS,
-	CGMANAGER,
-	CGFSNG,
-} cgroup_driver_t;
-
 struct cgroup_ops {
-	const char *name;
+	const char *driver;
+	const char *version;
 
 	void *(*init)(struct lxc_handler *handler);
 	void (*destroy)(void *hdata, struct lxc_conf *conf);
@@ -66,7 +61,6 @@ struct cgroup_ops {
 	bool (*mount_cgroup)(void *hdata, const char *root, int type);
 	int (*nrtasks)(void *hdata);
 	void (*disconnect)(void);
-	cgroup_driver_t driver;
 };
 
 extern bool cgroup_attach(const char *name, const char *lxcpath, pid_t pid);
@@ -87,7 +81,6 @@ extern int cgroup_num_hierarchies();
 extern bool cgroup_get_hierarchies(int i, char ***out);
 extern bool cgroup_unfreeze(struct lxc_handler *handler);
 extern void cgroup_disconnect(void);
-extern cgroup_driver_t cgroup_driver(void);
 
 extern void prune_init_scope(char *cg);
 extern bool is_crucial_cgroup_subsystem(const char *s);