Commit 9b846090 authored by Wenchao Hao's avatar Wenchao Hao Committed by Zheng Zengkai
Browse files

scsi: iscsi: Add helper functions to manage iscsi_cls_conn

mainline inclusion
from mainline-v5.18-rc1
commit ad515cad
category: bugfix
bugzilla: 187381, https://gitee.com/openeuler/kernel/issues/I5LBBP
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ad515cada7dac3cdf5e1ad77a0ed696f5f34e0ab

--------------------------------

 - 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: default avatarMike Christie <michael.christie@oracle.com>
Signed-off-by: default avatarWenchao Hao <haowenchao@huawei.com>
Signed-off-by: default avatarWu Bo <wubo40@huawei.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>

Conflict: commit 1a709181c1a0 ("[Huawei] scsi: iscsi: fix kabi broken
in struct iscsi_transport") introduce some conflicts.
Signed-off-by: default avatarYu Kuai <yukuai3@huawei.com>
Reviewed-by: default avatarJason Yan <yanaijie@huawei.com>
Signed-off-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
parent f392c8ed
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+101 −0
Original line number Diff line number Diff line
@@ -2384,6 +2384,107 @@ 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;
	struct iscsi_cls_conn_wrapper *conn_wrapper;

	conn_wrapper = kzalloc(sizeof(*conn_wrapper) + dd_size, GFP_KERNEL);
	if (!conn_wrapper)
		return NULL;

	conn = &conn_wrapper->conn;
	if (dd_size)
		conn->dd_data = &conn_wrapper[1];

	mutex_init(&conn->ep_mutex);
	spin_lock_init(&conn_wrapper->lock);
	INIT_LIST_HEAD(&conn->conn_list);
	INIT_WORK(&conn_wrapper->cleanup_work, iscsi_cleanup_conn_work_fn);
	conn->transport = transport;
	conn->cid = cid;
	WRITE_ONCE(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
+4 −0
Original line number Diff line number Diff line
@@ -468,6 +468,10 @@ 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 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);