fs/afs/server.h

   1 /* server.h: AFS server record
   2  *
   3  * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  12 #ifndef _LINUX_AFS_SERVER_H
  13 #define _LINUX_AFS_SERVER_H
  14
  15 #include "types.h"
  16 #include "kafstimod.h"
  17 #include <rxrpc/peer.h>
  18 #include <linux/rwsem.h>
  19
  20 extern spinlock_t afs_server_peer_lock;
  21
  22 /*****************************************************************************/
  23 /*
  24  * AFS server record
  25  */
  26 struct afs_server
  27 {
  28         atomic_t                usage;
  29         struct afs_cell         *cell;          /* cell in which server resides */
  30         struct list_head        link;           /* link in cell's server list */
  31         struct rw_semaphore     sem;            /* access lock */
  32         struct afs_timer        timeout;        /* graveyard timeout */
  33         struct in_addr          addr;           /* server address */
  34         struct rxrpc_peer       *peer;          /* peer record for this server */
  35         struct rxrpc_connection *vlserver;      /* connection to the volume location service */
  36
  37         /* file service access */
  38 #define AFS_SERVER_CONN_LIST_SIZE 2
  39         struct rxrpc_connection *fs_conn[AFS_SERVER_CONN_LIST_SIZE]; /* FS connections */
  40         unsigned                fs_conn_cnt[AFS_SERVER_CONN_LIST_SIZE]; /* per conn call count */
  41         struct list_head        fs_callq;       /* queue of processes waiting to make a call */
  42         spinlock_t              fs_lock;        /* access lock */
  43         int                     fs_state;       /* 0 or reason FS currently marked dead (-errno) */
  44         unsigned                fs_rtt;         /* FS round trip time */
  45         unsigned long           fs_act_jif;     /* time at which last activity occurred */
  46         unsigned long           fs_dead_jif;    /* time at which no longer to be considered dead */
  47
  48         /* callback promise management */
  49         struct list_head        cb_promises;    /* as yet unbroken promises from this server */
  50         spinlock_t              cb_lock;        /* access lock */
  51 };
  52
  53 extern int afs_server_lookup(struct afs_cell *cell,
  54                              const struct in_addr *addr,
  55                              struct afs_server **_server);
  56
  57 #define afs_get_server(S) do { atomic_inc(&(S)->usage); } while(0)
  58
  59 extern void afs_put_server(struct afs_server *server);
  60 extern void afs_server_do_timeout(struct afs_server *server);
  61
  62 extern int afs_server_find_by_peer(const struct rxrpc_peer *peer,
  63                                    struct afs_server **_server);
  64
  65 extern int afs_server_get_vlconn(struct afs_server *server,
  66                                  struct rxrpc_connection **_conn);
  67
  68 static inline
  69 struct afs_server *afs_server_get_from_peer(struct rxrpc_peer *peer)
  70 {
  71         struct afs_server *server;
  72
  73         spin_lock(&afs_server_peer_lock);
  74         server = peer->user;
  75         if (server)
  76                 afs_get_server(server);
  77         spin_unlock(&afs_server_peer_lock);
  78
  79         return server;
  80 }
  81
  82 /*****************************************************************************/
  83 /*
  84  * AFS server callslot grant record
  85  */
  86 struct afs_server_callslot
  87 {
  88         struct list_head        link;           /* link in server's list */
  89         struct task_struct      *task;          /* process waiting to make call */
  90         struct rxrpc_connection *conn;          /* connection to use (or NULL on error) */
  91         short                   nconn;          /* connection slot number (-1 on error) */
  92         char                    ready;          /* T when ready */
  93         int                     errno;          /* error number if nconn==-1 */
  94 };
  95
  96 extern int afs_server_request_callslot(struct afs_server *server,
  97                                        struct afs_server_callslot *callslot);
  98
  99 extern void afs_server_release_callslot(struct afs_server *server,
 100                                         struct afs_server_callslot *callslot);
 101
 102 #endif /* _LINUX_AFS_SERVER_H */