From ad515cada7dac3cdf5e1ad77a0ed696f5f34e0ab Mon Sep 17 00:00:00 2001 From: Wenchao Hao Date: Wed, 9 Mar 2022 20:57:57 -0500 Subject: scsi: iscsi: Add helper functions to manage iscsi_cls_conn - iscsi_alloc_conn(): Allocate and initialize iscsi_cls_conn - iscsi_add_conn(): Expose iscsi_cls_conn to userspace via sysfs - iscsi_remove_conn(): Remove iscsi_cls_conn from sysfs Link: https://lore.kernel.org/r/20220310015759.3296841-2-haowenchao@huawei.com Reviewed-by: Mike Christie Signed-off-by: Wenchao Hao Signed-off-by: Wu Bo Signed-off-by: Martin K. Petersen --- drivers/scsi/scsi_transport_iscsi.c | 97 +++++++++++++++++++++++++++++++++++++ 1 file changed, 97 insertions(+) (limited to 'drivers/scsi/scsi_transport_iscsi.c') diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c index 754277bec63a..fe586336591b 100644 --- a/drivers/scsi/scsi_transport_iscsi.c +++ b/drivers/scsi/scsi_transport_iscsi.c @@ -2317,6 +2317,103 @@ 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 + */ +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 will expose iscsi_cls_conn to sysfs so make sure the related + * resources for 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"); + 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); + 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 + * + * Remove iscsi_cls_conn from sysfs, and wait for previous + * read/write of iscsi_cls_conn's attributes in sysfs to finish. + */ +void iscsi_remove_conn(struct iscsi_cls_conn *conn) +{ + unsigned long flags; + + spin_lock_irqsave(&connlock, flags); + list_del(&conn->conn_list); + spin_unlock_irqrestore(&connlock, flags); + + transport_unregister_device(&conn->dev); + device_del(&conn->dev); +} +EXPORT_SYMBOL_GPL(iscsi_remove_conn); + /** * iscsi_create_conn - create iscsi class connection * @session: iscsi cls session -- cgit v1.2.3-59-g8ed1b