drbd: Add struct drbd_resource

In a first step, each resource has exactly one connection, and both objects are
allocated at the same time.  The final result will be one resource and zero or
more connections.

Only allow to delete a resource if all its connections are C_STANDALONE.
Stop the worker threads of all connections early enough.

Signed-off-by: Andreas Gruenbacher <agruen@linbit.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>

1 files changed, 40 insertions, 5 deletions

diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index b324314768f..b51ecdbdd30 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -105,7 +105,7 @@ struct drbd_connection;
 #define DEV (disk_to_dev(device->vdisk))
 
 #define conn_printk(LEVEL, TCONN, FMT, ARGS...) \
-	printk(LEVEL "d-con %s: " FMT, TCONN->name , ## ARGS)
+	printk(LEVEL "d-con %s: " FMT, TCONN->resource->name , ## ARGS)
 #define conn_alert(TCONN, FMT, ARGS...)  conn_printk(KERN_ALERT, TCONN, FMT, ## ARGS)
 #define conn_crit(TCONN, FMT, ARGS...)   conn_printk(KERN_CRIT, TCONN, FMT, ## ARGS)
 #define conn_err(TCONN, FMT, ARGS...)    conn_printk(KERN_ERR, TCONN, FMT, ## ARGS)
@@ -167,7 +167,7 @@ drbd_insert_fault(struct drbd_device *device, unsigned int type) {
 
 extern struct ratelimit_state drbd_ratelimit_state;
 extern struct idr drbd_devices; /* RCU, updates: genl_lock() */
-extern struct list_head drbd_connections; /* RCU, updates: genl_lock() */
+extern struct list_head drbd_resources; /* RCU, updates: genl_lock() */
 
 extern const char *cmdname(enum drbd_packet cmd);
 
@@ -536,9 +536,16 @@ enum {
 	DISCONNECT_SENT,
 };
 
-struct drbd_connection {			/* is a resource from the config file */
-	char *name;			/* Resource name */
-	struct list_head connections;	/* linked on global drbd_connections */
+struct drbd_resource {
+	char *name;
+	struct kref kref;
+	struct list_head connections;
+	struct list_head resources;
+};
+
+struct drbd_connection {
+	struct list_head connections;
+	struct drbd_resource *resource;
 	struct kref kref;
 	struct idr volumes;		/* <connection, vnr> to device mapping */
 	enum drbd_conns cstate;		/* Only C_STANDALONE to C_WF_REPORT_PARAMS */
@@ -779,6 +786,24 @@ static inline struct drbd_peer_device *first_peer_device(struct drbd_device *dev
 	return list_first_entry(&device->peer_devices, struct drbd_peer_device, peer_devices);
 }
 
+#define for_each_resource(resource, _resources) \
+	list_for_each_entry(resource, _resources, resources)
+
+#define for_each_resource_rcu(resource, _resources) \
+	list_for_each_entry_rcu(resource, _resources, resources)
+
+#define for_each_resource_safe(resource, tmp, _resources) \
+	list_for_each_entry_safe(resource, tmp, _resources, resources)
+
+#define for_each_connection(connection, resource) \
+	list_for_each_entry(connection, &resource->connections, connections)
+
+#define for_each_connection_rcu(connection, resource) \
+	list_for_each_entry_rcu(connection, &resource->connections, connections)
+
+#define for_each_connection_safe(connection, tmp, resource) \
+	list_for_each_entry_safe(connection, tmp, &resource->connections, connections)
+
 #define for_each_peer_device(peer_device, device) \
 	list_for_each_entry(peer_device, &device->peer_devices, peer_devices)
 
@@ -1177,12 +1202,16 @@ extern int conn_lowest_minor(struct drbd_connection *connection);
 enum drbd_ret_code drbd_create_minor(struct drbd_connection *connection, unsigned int minor, int vnr);
 extern void drbd_destroy_device(struct kref *kref);
 
+extern struct drbd_resource *drbd_create_resource(const char *name);
+extern void drbd_free_resource(struct drbd_resource *resource);
+
 extern int set_resource_options(struct drbd_connection *connection, struct res_opts *res_opts);
 extern struct drbd_connection *conn_create(const char *name, struct res_opts *res_opts);
 extern void drbd_destroy_connection(struct kref *kref);
 struct drbd_connection *conn_get_by_name(const char *name);
 extern struct drbd_connection *conn_get_by_addrs(void *my_addr, int my_addr_len,
 					    void *peer_addr, int peer_addr_len);
+extern void drbd_destroy_resource(struct kref *kref);
 extern void conn_free_crypto(struct drbd_connection *connection);
 
 extern int proc_details;
@@ -2082,4 +2111,10 @@ static inline void drbd_md_flush(struct drbd_device *device)
 	}
 }
 
+static inline struct drbd_connection *first_connection(struct drbd_resource *resource)
+{
+	return list_first_entry(&resource->connections,
+				struct drbd_connection, connections);
+}
+
 #endif