Linux 2.6.13-rc4
[linux-2.6/next.git] / fs / afs / volume.h
blob1e691889c4c96911bc036f7b7539184b4ccc10fb
1 /* volume.h: AFS volume management
3 * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
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.
12 #ifndef _LINUX_AFS_VOLUME_H
13 #define _LINUX_AFS_VOLUME_H
15 #include "types.h"
16 #include "fsclient.h"
17 #include "kafstimod.h"
18 #include "kafsasyncd.h"
19 #include "cache.h"
21 #define __packed __attribute__((packed))
23 typedef enum {
24 AFS_VLUPD_SLEEP, /* sleeping waiting for update timer to fire */
25 AFS_VLUPD_PENDING, /* on pending queue */
26 AFS_VLUPD_INPROGRESS, /* op in progress */
27 AFS_VLUPD_BUSYSLEEP, /* sleeping because server returned EBUSY */
29 } __attribute__((packed)) afs_vlocation_upd_t;
31 /*****************************************************************************/
33 * entry in the cached volume location catalogue
35 struct afs_cache_vlocation
37 uint8_t name[64]; /* volume name (lowercase, padded with NULs) */
38 uint8_t nservers; /* number of entries used in servers[] */
39 uint8_t vidmask; /* voltype mask for vid[] */
40 uint8_t srvtmask[8]; /* voltype masks for servers[] */
41 #define AFS_VOL_VTM_RW 0x01 /* R/W version of the volume is available (on this server) */
42 #define AFS_VOL_VTM_RO 0x02 /* R/O version of the volume is available (on this server) */
43 #define AFS_VOL_VTM_BAK 0x04 /* backup version of the volume is available (on this server) */
45 afs_volid_t vid[3]; /* volume IDs for R/W, R/O and Bak volumes */
46 struct in_addr servers[8]; /* fileserver addresses */
47 time_t rtime; /* last retrieval time */
50 #ifdef AFS_CACHING_SUPPORT
51 extern struct cachefs_index_def afs_vlocation_cache_index_def;
52 #endif
54 /*****************************************************************************/
56 * volume -> vnode hash table entry
58 struct afs_cache_vhash
60 afs_voltype_t vtype; /* which volume variation */
61 uint8_t hash_bucket; /* which hash bucket this represents */
62 } __attribute__((packed));
64 #ifdef AFS_CACHING_SUPPORT
65 extern struct cachefs_index_def afs_volume_cache_index_def;
66 #endif
68 /*****************************************************************************/
70 * AFS volume location record
72 struct afs_vlocation
74 atomic_t usage;
75 struct list_head link; /* link in cell volume location list */
76 struct afs_timer timeout; /* decaching timer */
77 struct afs_cell *cell; /* cell to which volume belongs */
78 #ifdef AFS_CACHING_SUPPORT
79 struct cachefs_cookie *cache; /* caching cookie */
80 #endif
81 struct afs_cache_vlocation vldb; /* volume information DB record */
82 struct afs_volume *vols[3]; /* volume access record pointer (index by type) */
83 rwlock_t lock; /* access lock */
84 unsigned long read_jif; /* time at which last read from vlserver */
85 struct afs_timer upd_timer; /* update timer */
86 struct afs_async_op upd_op; /* update operation */
87 afs_vlocation_upd_t upd_state; /* update state */
88 unsigned short upd_first_svix; /* first server index during update */
89 unsigned short upd_curr_svix; /* current server index during update */
90 unsigned short upd_rej_cnt; /* ENOMEDIUM count during update */
91 unsigned short upd_busy_cnt; /* EBUSY count during update */
92 unsigned short valid; /* T if valid */
95 extern int afs_vlocation_lookup(struct afs_cell *cell,
96 const char *name,
97 unsigned namesz,
98 struct afs_vlocation **_vlocation);
100 #define afs_get_vlocation(V) do { atomic_inc(&(V)->usage); } while(0)
102 extern void afs_put_vlocation(struct afs_vlocation *vlocation);
103 extern void afs_vlocation_do_timeout(struct afs_vlocation *vlocation);
105 /*****************************************************************************/
107 * AFS volume access record
109 struct afs_volume
111 atomic_t usage;
112 struct afs_cell *cell; /* cell to which belongs (unrefd ptr) */
113 struct afs_vlocation *vlocation; /* volume location */
114 #ifdef AFS_CACHING_SUPPORT
115 struct cachefs_cookie *cache; /* caching cookie */
116 #endif
117 afs_volid_t vid; /* volume ID */
118 afs_voltype_t __packed type; /* type of volume */
119 char type_force; /* force volume type (suppress R/O -> R/W) */
120 unsigned short nservers; /* number of server slots filled */
121 unsigned short rjservers; /* number of servers discarded due to -ENOMEDIUM */
122 struct afs_server *servers[8]; /* servers on which volume resides (ordered) */
123 struct rw_semaphore server_sem; /* lock for accessing current server */
126 extern int afs_volume_lookup(const char *name,
127 struct afs_cell *cell,
128 int rwpath,
129 struct afs_volume **_volume);
131 #define afs_get_volume(V) do { atomic_inc(&(V)->usage); } while(0)
133 extern void afs_put_volume(struct afs_volume *volume);
135 extern int afs_volume_pick_fileserver(struct afs_volume *volume,
136 struct afs_server **_server);
138 extern int afs_volume_release_fileserver(struct afs_volume *volume,
139 struct afs_server *server,
140 int result);
142 #endif /* _LINUX_AFS_VOLUME_H */