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1/* volume.h: AFS volume management
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_VOLUME_H
13#define _LINUX_AFS_VOLUME_H
14
15#include "types.h"
16#include "fsclient.h"
17#include "kafstimod.h"
18#include "kafsasyncd.h"
19#include "cache.h"
20
21typedef enum {
22 AFS_VLUPD_SLEEP, /* sleeping waiting for update timer to fire */
23 AFS_VLUPD_PENDING, /* on pending queue */
24 AFS_VLUPD_INPROGRESS, /* op in progress */
25 AFS_VLUPD_BUSYSLEEP, /* sleeping because server returned EBUSY */
26
27} __attribute__((packed)) afs_vlocation_upd_t;
28
29/*****************************************************************************/
30/*
31 * entry in the cached volume location catalogue
32 */
33struct afs_cache_vlocation
34{
35 uint8_t name[64]; /* volume name (lowercase, padded with NULs) */
36 uint8_t nservers; /* number of entries used in servers[] */
37 uint8_t vidmask; /* voltype mask for vid[] */
38 uint8_t srvtmask[8]; /* voltype masks for servers[] */
39#define AFS_VOL_VTM_RW 0x01 /* R/W version of the volume is available (on this server) */
40#define AFS_VOL_VTM_RO 0x02 /* R/O version of the volume is available (on this server) */
41#define AFS_VOL_VTM_BAK 0x04 /* backup version of the volume is available (on this server) */
42
43 afs_volid_t vid[3]; /* volume IDs for R/W, R/O and Bak volumes */
44 struct in_addr servers[8]; /* fileserver addresses */
45 time_t rtime; /* last retrieval time */
46};
47
48#ifdef AFS_CACHING_SUPPORT
49extern struct cachefs_index_def afs_vlocation_cache_index_def;
50#endif
51
52/*****************************************************************************/
53/*
54 * volume -> vnode hash table entry
55 */
56struct afs_cache_vhash
57{
58 afs_voltype_t vtype; /* which volume variation */
59 uint8_t hash_bucket; /* which hash bucket this represents */
60} __attribute__((packed));
61
62#ifdef AFS_CACHING_SUPPORT
63extern struct cachefs_index_def afs_volume_cache_index_def;
64#endif
65
66/*****************************************************************************/
67/*
68 * AFS volume location record
69 */
70struct afs_vlocation
71{
72 atomic_t usage;
73 struct list_head link; /* link in cell volume location list */
74 struct afs_timer timeout; /* decaching timer */
75 struct afs_cell *cell; /* cell to which volume belongs */
76#ifdef AFS_CACHING_SUPPORT
77 struct cachefs_cookie *cache; /* caching cookie */
78#endif
79 struct afs_cache_vlocation vldb; /* volume information DB record */
80 struct afs_volume *vols[3]; /* volume access record pointer (index by type) */
81 rwlock_t lock; /* access lock */
82 unsigned long read_jif; /* time at which last read from vlserver */
83 struct afs_timer upd_timer; /* update timer */
84 struct afs_async_op upd_op; /* update operation */
85 afs_vlocation_upd_t upd_state; /* update state */
86 unsigned short upd_first_svix; /* first server index during update */
87 unsigned short upd_curr_svix; /* current server index during update */
88 unsigned short upd_rej_cnt; /* ENOMEDIUM count during update */
89 unsigned short upd_busy_cnt; /* EBUSY count during update */
90 unsigned short valid; /* T if valid */
91};
92
93extern int afs_vlocation_lookup(struct afs_cell *cell,
94 const char *name,
95 unsigned namesz,
96 struct afs_vlocation **_vlocation);
97
98#define afs_get_vlocation(V) do { atomic_inc(&(V)->usage); } while(0)
99
100extern void afs_put_vlocation(struct afs_vlocation *vlocation);
101extern void afs_vlocation_do_timeout(struct afs_vlocation *vlocation);
102
103/*****************************************************************************/
104/*
105 * AFS volume access record
106 */
107struct afs_volume
108{
109 atomic_t usage;
110 struct afs_cell *cell; /* cell to which belongs (unrefd ptr) */
111 struct afs_vlocation *vlocation; /* volume location */
112#ifdef AFS_CACHING_SUPPORT
113 struct cachefs_cookie *cache; /* caching cookie */
114#endif
115 afs_volid_t vid; /* volume ID */
116 afs_voltype_t type; /* type of volume */
117 char type_force; /* force volume type (suppress R/O -> R/W) */
118 unsigned short nservers; /* number of server slots filled */
119 unsigned short rjservers; /* number of servers discarded due to -ENOMEDIUM */
120 struct afs_server *servers[8]; /* servers on which volume resides (ordered) */
121 struct rw_semaphore server_sem; /* lock for accessing current server */
122};
123
124extern int afs_volume_lookup(const char *name,
125 struct afs_cell *cell,
126 int rwpath,
127 struct afs_volume **_volume);
128
129#define afs_get_volume(V) do { atomic_inc(&(V)->usage); } while(0)
130
131extern void afs_put_volume(struct afs_volume *volume);
132
133extern int afs_volume_pick_fileserver(struct afs_volume *volume,
134 struct afs_server **_server);
135
136extern int afs_volume_release_fileserver(struct afs_volume *volume,
137 struct afs_server *server,
138 int result);
139
140#endif /* _LINUX_AFS_VOLUME_H */