fs/afs/cell.h

   1 /* AFS cell 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 AFS_CELL_H
  13 #define AFS_CELL_H
  14
  15 #include "types.h"
  16 #include "cache.h"
  17
  18 #define AFS_CELL_MAX_ADDRS 15
  19
  20 extern volatile int afs_cells_being_purged; /* T when cells are being purged by rmmod */
  21
  22 /*
  23  * entry in the cached cell catalogue
  24  */
  25 struct afs_cache_cell {
  26         char                    name[64];       /* cell name (padded with NULs) */
  27         struct in_addr          vl_servers[15]; /* cached cell VL servers */
  28 };
  29
  30 /*
  31  * AFS cell record
  32  */
  33 struct afs_cell {
  34         atomic_t                usage;
  35         struct list_head        link;           /* main cell list link */
  36         struct list_head        proc_link;      /* /proc cell list link */
  37         struct proc_dir_entry   *proc_dir;      /* /proc dir for this cell */
  38 #ifdef AFS_CACHING_SUPPORT
  39         struct cachefs_cookie   *cache;         /* caching cookie */
  40 #endif
  41
  42         /* server record management */
  43         rwlock_t                sv_lock;        /* active server list lock */
  44         struct list_head        sv_list;        /* active server list */
  45         struct list_head        sv_graveyard;   /* inactive server list */
  46         spinlock_t              sv_gylock;      /* inactive server list lock */
  47
  48         /* volume location record management */
  49         struct rw_semaphore     vl_sem;         /* volume management serialisation semaphore */
  50         struct list_head        vl_list;        /* cell's active VL record list */
  51         struct list_head        vl_graveyard;   /* cell's inactive VL record list */
  52         spinlock_t              vl_gylock;      /* graveyard lock */
  53         unsigned short          vl_naddrs;      /* number of VL servers in addr list */
  54         unsigned short          vl_curr_svix;   /* current server index */
  55         struct in_addr          vl_addrs[AFS_CELL_MAX_ADDRS];   /* cell VL server addresses */
  56
  57         char                    name[0];        /* cell name - must go last */
  58 };
  59
  60 extern int afs_cell_init(char *);
  61 extern int afs_cell_create(const char *, char *, struct afs_cell **);
  62 extern int afs_cell_lookup(const char *, unsigned, struct afs_cell **);
  63
  64 #define afs_get_cell(C) do { atomic_inc(&(C)->usage); } while(0)
  65
  66 extern struct afs_cell *afs_get_cell_maybe(struct afs_cell **);
  67 extern void afs_put_cell(struct afs_cell *);
  68 extern void afs_cell_purge(void);
  69
  70 #endif /* AFS_CELL_H */