iscsi_alloc_conn(): alloc and initialize iscsi_cls_conn
iscsi_add_conn(): expose iscsi_cls_conn to userspace's via sysfs.
iscsi_remove_conn(): remove iscsi_cls_conn from sysfs
iscsi_free_conn(): free iscsi_cls_conn
Signed-off-by: Wenchao Hao <haowenchao@xxxxxxxxxx>
Signed-off-by: Wu Bo <wubo40@xxxxxxxxxx>
---
drivers/scsi/scsi_transport_iscsi.c | 107 ++++++++++++++++++++++++++++
include/scsi/scsi_transport_iscsi.h | 5 ++
2 files changed, 112 insertions(+)
diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index 554b6f784223..8e97c6f88359 100644
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -2340,6 +2340,113 @@ void iscsi_free_session(struct iscsi_cls_session *session)
}
EXPORT_SYMBOL_GPL(iscsi_free_session);
+/**
+ * iscsi_alloc_conn - alloc iscsi class connection
+ * @session: iscsi cls session
+ * @dd_size: private driver data size
+ * @cid: connection id
+ *
+ * This can be called from a LLD or iscsi_transport. The connection
+ * is child of the session so cid must be unique for all connections
+ * on the session.
+ *
+ * Since we do not support MCS, cid will normally be zero. In some cases
+ * for software iscsi we could be trying to preallocate a connection struct
+ * in which case there could be two connection structs and cid would be
+ * non-zero.
+ */
+struct iscsi_cls_conn *
+iscsi_alloc_conn(struct iscsi_cls_session *session, int dd_size, uint32_t cid)
+{
+ struct iscsi_transport *transport = session->transport;
+ struct iscsi_cls_conn *conn;
+
+ conn = kzalloc(sizeof(*conn) + dd_size, GFP_KERNEL);
+ if (!conn)
+ return NULL;
+ if (dd_size)
+ conn->dd_data = &conn[1];
+
+ mutex_init(&conn->ep_mutex);
+ INIT_LIST_HEAD(&conn->conn_list);
+ INIT_WORK(&conn->cleanup_work, iscsi_cleanup_conn_work_fn);
+ conn->transport = transport;
+ conn->cid = cid;
+ conn->state = ISCSI_CONN_DOWN;
+
+ /* this is released in the dev's release function */
+ if (!get_device(&session->dev))
+ goto free_conn;
+
+ dev_set_name(&conn->dev, "connection%d:%u", session->sid, cid);
+ device_initialize(&conn->dev);
+ conn->dev.parent = &session->dev;
+ conn->dev.release = iscsi_conn_release;
+
+ return conn;
+
+free_conn:
+ kfree(conn);
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(iscsi_alloc_conn);
+
+/**
+ * iscsi_add_conn - add iscsi class connection
+ * @conn: iscsi cls connection
+ *
+ * this would expose iscsi_cls_conn to sysfs, so make sure the related
+ * resources when access sysfs attributes are initialized before calling this.
+ */
+int iscsi_add_conn(struct iscsi_cls_conn *conn)
+{
+ int err;
+ unsigned long flags;
+ struct iscsi_cls_session *session = iscsi_dev_to_session(conn->dev.parent);
+
+ err = device_add(&conn->dev);
+ if (err) {
+ iscsi_cls_session_printk(KERN_ERR, session,
+ "could not register connection's dev\n");
+ put_device(&session->dev);
+ return err;
+ }
+ err = transport_register_device(&conn->dev);
+ if (err) {
+ iscsi_cls_session_printk(KERN_ERR, session,
+ "could not register transport's dev\n");
+ device_del(&conn->dev);
+ put_device(&session->dev);
+ return err;
+ }
+
+ spin_lock_irqsave(&connlock, flags);
+ list_add(&conn->conn_list, &connlist);
+ spin_unlock_irqrestore(&connlock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(iscsi_add_conn);
+
+/**
+ * iscsi_remove_conn - remove iscsi class connection from sysfs
+ * @conn: iscsi cls connection
+ *
+ * this would remove iscsi_cls_conn from sysfs, and wait for previous
+ * read/write of iscsi_cls_conn's attributes in sysfs finishing
+ */
+void iscsi_remove_conn(struct iscsi_cls_conn *conn)
+{
+ device_del(&conn->dev);
+}
+EXPORT_SYMBOL_GPL(iscsi_remove_conn);
+
+void iscsi_free_conn(struct iscsi_cls_conn *conn)
+{
+ put_device(&conn->dev);
+}
+EXPORT_SYMBOL_GPL(iscsi_free_conn);
+
/**
* iscsi_create_conn - create iscsi class connection
* @session: iscsi cls session
diff --git a/include/scsi/scsi_transport_iscsi.h b/include/scsi/scsi_transport_iscsi.h
index c5d7810fd792..346f65bc3861 100644
--- a/include/scsi/scsi_transport_iscsi.h
+++ b/include/scsi/scsi_transport_iscsi.h
@@ -441,6 +441,11 @@ extern struct iscsi_cls_session *iscsi_create_session(struct Scsi_Host *shost,
unsigned int target_id);
extern void iscsi_remove_session(struct iscsi_cls_session *session);
extern void iscsi_free_session(struct iscsi_cls_session *session);
+extern struct iscsi_cls_conn *iscsi_alloc_conn(struct iscsi_cls_session *sess,
+ int dd_size, uint32_t cid);
+extern int iscsi_add_conn(struct iscsi_cls_conn *conn);
+extern void iscsi_remove_conn(struct iscsi_cls_conn *conn);
+extern void iscsi_free_conn(struct iscsi_cls_conn *conn);
extern struct iscsi_cls_conn *iscsi_create_conn(struct iscsi_cls_session *sess,
int dd_size, uint32_t cid);
extern void iscsi_put_conn(struct iscsi_cls_conn *conn);
--
2.32.0
