include/linux/sunrpc/xprtmultipath.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * RPC client multipathing definitions
   4  *
   5  * Copyright (c) 2015, 2016, Primary Data, Inc. All rights reserved.
   6  *
   7  * Trond Myklebust <trond.myklebust@primarydata.com>
   8  */
   9 #ifndef _NET_SUNRPC_XPRTMULTIPATH_H
  10 #define _NET_SUNRPC_XPRTMULTIPATH_H
  11
  12 struct rpc_xprt_iter_ops;
  13 struct rpc_sysfs_xprt_switch;
  14 struct rpc_xprt_switch {
  15         spinlock_t              xps_lock;
  16         struct kref             xps_kref;
  17
  18         unsigned int            xps_id;
  19         unsigned int            xps_nxprts;
  20         unsigned int            xps_nactive;
  21         unsigned int            xps_nunique_destaddr_xprts;
  22         atomic_long_t           xps_queuelen;
  23         struct list_head        xps_xprt_list;
  24
  25         struct net *            xps_net;
  26
  27         const struct rpc_xprt_iter_ops *xps_iter_ops;
  28
  29         struct rpc_sysfs_xprt_switch *xps_sysfs;
  30         struct rcu_head         xps_rcu;
  31 };
  32
  33 struct rpc_xprt_iter {
  34         struct rpc_xprt_switch __rcu *xpi_xpswitch;
  35         struct rpc_xprt *       xpi_cursor;
  36
  37         const struct rpc_xprt_iter_ops *xpi_ops;
  38 };
  39
  40
  41 struct rpc_xprt_iter_ops {
  42         void (*xpi_rewind)(struct rpc_xprt_iter *);
  43         struct rpc_xprt *(*xpi_xprt)(struct rpc_xprt_iter *);
  44         struct rpc_xprt *(*xpi_next)(struct rpc_xprt_iter *);
  45 };
  46
  47 extern struct rpc_xprt_switch *xprt_switch_alloc(struct rpc_xprt *xprt,
  48                 gfp_t gfp_flags);
  49
  50 extern struct rpc_xprt_switch *xprt_switch_get(struct rpc_xprt_switch *xps);
  51 extern void xprt_switch_put(struct rpc_xprt_switch *xps);
  52
  53 extern void rpc_xprt_switch_set_roundrobin(struct rpc_xprt_switch *xps);
  54
  55 extern void rpc_xprt_switch_add_xprt(struct rpc_xprt_switch *xps,
  56                 struct rpc_xprt *xprt);
  57 extern void rpc_xprt_switch_remove_xprt(struct rpc_xprt_switch *xps,
  58                 struct rpc_xprt *xprt, bool offline);
  59
  60 extern void xprt_iter_init(struct rpc_xprt_iter *xpi,
  61                 struct rpc_xprt_switch *xps);
  62
  63 extern void xprt_iter_init_listall(struct rpc_xprt_iter *xpi,
  64                 struct rpc_xprt_switch *xps);
  65
  66 extern void xprt_iter_init_listoffline(struct rpc_xprt_iter *xpi,
  67                 struct rpc_xprt_switch *xps);
  68
  69 extern void xprt_iter_destroy(struct rpc_xprt_iter *xpi);
  70
  71 extern void xprt_iter_rewind(struct rpc_xprt_iter *xpi);
  72
  73 extern struct rpc_xprt_switch *xprt_iter_xchg_switch(
  74                 struct rpc_xprt_iter *xpi,
  75                 struct rpc_xprt_switch *newswitch);
  76
  77 extern struct rpc_xprt *xprt_iter_xprt(struct rpc_xprt_iter *xpi);
  78 extern struct rpc_xprt *xprt_iter_get_next(struct rpc_xprt_iter *xpi);
  79
  80 extern bool rpc_xprt_switch_has_addr(struct rpc_xprt_switch *xps,
  81                 const struct sockaddr *sap);
  82
  83 extern void xprt_multipath_cleanup_ids(void);
  84
  85 #endif