/* SPDX-License-Identifier: GPL-2.0 */
/*
 * RPC client multipathing definitions
 *
 * Copyright (c) 2015, 2016, Primary Data, Inc. All rights reserved.
 *
 * Trond Myklebust <trond.myklebust@primarydata.com>
 */
#ifndef _NET_SUNRPC_XPRTMULTIPATH_H
#define _NET_SUNRPC_XPRTMULTIPATH_H

struct rpc_xprt_iter_ops;
struct rpc_sysfs_xprt_switch;
struct rpc_xprt_switch {
        spinlock_t              xps_lock;
        struct kref             xps_kref;

        unsigned int            xps_id;
        unsigned int            xps_nxprts;
        unsigned int            xps_nactive;
        unsigned int            xps_nunique_destaddr_xprts;
        atomic_long_t           xps_queuelen;
        struct list_head        xps_xprt_list;

        struct net *            xps_net;

        const struct rpc_xprt_iter_ops *xps_iter_ops;

        struct rpc_sysfs_xprt_switch *xps_sysfs;
        struct rcu_head         xps_rcu;
};

struct rpc_xprt_iter {
        struct rpc_xprt_switch __rcu *xpi_xpswitch;
        struct rpc_xprt *       xpi_cursor;

        const struct rpc_xprt_iter_ops *xpi_ops;
};


struct rpc_xprt_iter_ops {
        void (*xpi_rewind)(struct rpc_xprt_iter *);
        struct rpc_xprt *(*xpi_xprt)(struct rpc_xprt_iter *);
        struct rpc_xprt *(*xpi_next)(struct rpc_xprt_iter *);
};

extern struct rpc_xprt_switch *xprt_switch_alloc(struct rpc_xprt *xprt,
                gfp_t gfp_flags);

extern struct rpc_xprt_switch *xprt_switch_get(struct rpc_xprt_switch *xps);
extern void xprt_switch_put(struct rpc_xprt_switch *xps);

extern void rpc_xprt_switch_set_roundrobin(struct rpc_xprt_switch *xps);

extern void rpc_xprt_switch_add_xprt(struct rpc_xprt_switch *xps,
                struct rpc_xprt *xprt);
extern void rpc_xprt_switch_remove_xprt(struct rpc_xprt_switch *xps,
                struct rpc_xprt *xprt, bool offline);
extern struct rpc_xprt *rpc_xprt_switch_get_main_xprt(struct rpc_xprt_switch *xps);

extern void xprt_iter_init(struct rpc_xprt_iter *xpi,
                struct rpc_xprt_switch *xps);

extern void xprt_iter_init_listall(struct rpc_xprt_iter *xpi,
                struct rpc_xprt_switch *xps);

extern void xprt_iter_init_listoffline(struct rpc_xprt_iter *xpi,
                struct rpc_xprt_switch *xps);

extern void xprt_iter_destroy(struct rpc_xprt_iter *xpi);

extern void xprt_iter_rewind(struct rpc_xprt_iter *xpi);

extern struct rpc_xprt_switch *xprt_iter_xchg_switch(
                struct rpc_xprt_iter *xpi,
                struct rpc_xprt_switch *newswitch);

extern struct rpc_xprt *xprt_iter_xprt(struct rpc_xprt_iter *xpi);
extern struct rpc_xprt *xprt_iter_get_next(struct rpc_xprt_iter *xpi);

extern bool rpc_xprt_switch_has_addr(struct rpc_xprt_switch *xps,
                const struct sockaddr *sap);

extern void xprt_multipath_cleanup_ids(void);

#endif