1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
|
/*
* fh.h This module handles the file-handle cache.
*
* Authors: Mark A. Shand, May 1988
* Don Becker, <becker@super.org>
* Rick Sladkey, <jrs@world.std.com>
* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
*
* Copyright 1988 Mark A. Shand
* This software maybe be used for any purpose provided
* the above copyright notice is retained. It is supplied
* as is, with no warranty expressed or implied.
*/
/* Compatibility between mount and nfs_prot. */
#ifndef NFS_FHSIZE
# define NFS_FHSIZE FHSIZE
#endif
#define FHC_XONLY_PATH 001 /* NOT USED ANYMORE */
#define FHC_ATTRVALID 002
#define FHC_NFSMOUNTED 004
/* Modes for fh_find */
#define FHFIND_FEXISTS 0 /* file must exist */
#define FHFIND_FCREATE 1 /* file will be created */
#define FHFIND_FCACHED 2 /* fh must be in cache */
#define FHFIND_CHECK 0x10 /* Check for cached path */
/*
* This defines the maximum number of handles nfsd will cache.
*/
#define FH_CACHE_LIMIT 2000
/*
* This defines the maximum number of file nfsd may keep open for NFS I/O.
* It used to be 8...
*/
#define FD_CACHE_LIMIT (3*FOPEN_MAX/4)
/* The following affect cache expiry.
* CLOSE_INTERVAL applies to the closing of inactive file descriptors
* The fd expiry interval is actually quite low because we want to have big
* files actually go away when they have been deleted behind our back.
* We also want to be able to execute programs that have just been copied
* via NFS.
*
* DISCARD_INTERVAL is the time in seconds nfsd will cache file handles
* unless it's being flooded with other requests. This value is possibly
* still too large, but the original was 2 days. --okir
*/
#define FLUSH_INTERVAL 5 /* 5 seconds */
#define BUSY_RETRY_INTERVAL 2 /* 2 seconds */
#define CLOSE_INTERVAL 5 /* 5 seconds */
#define DISCARD_INTERVAL (60*60) /* 1 hour */
/*
* Type of a pseudo inode
*/
typedef __u32 psi_t;
/*
* Hashed search path to this file.
* path is: hash_path[1] ... hash_path[hash_path[0]]
*
* hash_path[hash_path[0]+1] ... hash_path[HP_LEN-1] == 0
*/
#define HP_LEN (NFS_FHSIZE - sizeof(psi_t))
typedef struct {
psi_t psi;
__u8 hash_path[HP_LEN];
} svc_fh;
typedef enum { inactive, active } mutex;
/*
* Paths constructed in this system always consist of real directories
* (excepting the last element) i.e. they do not contain symbolic links.
* This is guaranteed by the way NFS constructs the paths.
* As a consequence we may assume that
* /x/y/z/.. == /x/y
* and /x/y/z/. == /x/y/z
* provided that z != . && z != ..
* These relations are exploited in fh_compose.
*
* Further assumptions:
* All cached pathnames consist of a leading /
* followed by zero or more / separated names
* s.t.
* name != .
* name != ..
* index(name, '/') == 0
*/
typedef struct fhcache {
struct fhcache * next;
struct fhcache * prev;
struct fhcache * hash_next;
struct fhcache * fd_next;
struct fhcache * fd_prev;
svc_fh h;
int fd;
int omode;
char * path;
time_t last_used;
nfs_client * last_clnt;
nfs_mount * last_mount;
uid_t last_uid;
int flags;
struct stat attrs;
} fhcache;
/* Global FH variables. */
extern int _rpcpmstart;
extern int fh_initialized;
/* Global function prototypes. */
extern nfsstat nfs_errno(void);
extern psi_t pseudo_inode(ino_t inode, dev_t dev);
extern void fh_init(void);
extern char *fh_pr(nfs_fh *fh);
extern int fh_create(nfs_fh *fh, char *path);
extern fhcache *fh_find(svc_fh *h, int create);
extern char *fh_path(nfs_fh *fh, nfsstat *status);
extern int path_open(char *path, int omode, int perm);
extern int fh_fd(fhcache *fhc, nfsstat *status, int omode);
extern void fd_inactive(int fd);
extern nfsstat fh_compose(diropargs *dopa, nfs_fh *new_fh,
struct stat *sbp, int fd,
int omode, int public);
extern psi_t fh_psi(nfs_fh *fh);
extern void fh_remove(char *path);
extern nfs_fh *fh_handle(fhcache *fhc);
extern void fh_flush(int force);
extern RETSIGTYPE flush_cache(int sig);
extern int nfsmounted(const char *path, struct stat *sbp);
/* End of fh.h. */
|
