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/*
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/*
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 * Copyright (c) 2008 Jakub Jermar
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 * Copyright (c) 2008 Jakub Jermar
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 * All rights reserved.
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 * All rights reserved.
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 *
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * modification, are permitted provided that the following conditions
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 * are met:
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 * are met:
8
 *
8
 *
9
 * - Redistributions of source code must retain the above copyright
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 * - Redistributions of source code must retain the above copyright
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 *   notice, this list of conditions and the following disclaimer.
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 *   notice, this list of conditions and the following disclaimer.
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 * - Redistributions in binary form must reproduce the above copyright
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 * - Redistributions in binary form must reproduce the above copyright
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 *   notice, this list of conditions and the following disclaimer in the
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 *   notice, this list of conditions and the following disclaimer in the
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 *   documentation and/or other materials provided with the distribution.
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 *   documentation and/or other materials provided with the distribution.
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 * - The name of the author may not be used to endorse or promote products
14
 * - The name of the author may not be used to endorse or promote products
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 *   derived from this software without specific prior written permission.
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 *   derived from this software without specific prior written permission.
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 *
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 *
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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 */
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 */
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29
/** @addtogroup fs
29
/** @addtogroup fs
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 * @{
30
 * @{
31
 */
31
 */
32
 
32
 
33
#ifndef VFS_VFS_H_
33
#ifndef VFS_VFS_H_
34
#define VFS_VFS_H_
34
#define VFS_VFS_H_
35
 
35
 
36
#include <ipc/ipc.h>
36
#include <ipc/ipc.h>
37
#include <libadt/list.h>
37
#include <libadt/list.h>
38
#include <atomic.h>
38
#include <atomic.h>
39
#include <rwlock.h>
39
#include <rwlock.h>
40
#include <sys/types.h>
40
#include <sys/types.h>
41
#include <bool.h>
41
#include <bool.h>
42
 
42
 
43
#define dprintf(...)    printf(__VA_ARGS__)
43
#define dprintf(...)    printf(__VA_ARGS__)
44
 
44
 
45
#define VFS_FIRST   IPC_FIRST_USER_METHOD
45
#define VFS_FIRST   IPC_FIRST_USER_METHOD
46
 
46
 
47
#define IPC_METHOD_TO_VFS_OP(m) ((m) - VFS_FIRST)   
47
#define IPC_METHOD_TO_VFS_OP(m) ((m) - VFS_FIRST)   
48
 
48
 
49
typedef enum {
49
typedef enum {
50
    VFS_OPEN = VFS_FIRST,
50
    VFS_READ = VFS_FIRST,
51
    VFS_CLOSE,
-
 
52
    VFS_READ,
-
 
53
    VFS_WRITE,
51
    VFS_WRITE,
54
    VFS_TRUNCATE,
52
    VFS_TRUNCATE,
55
    VFS_RENAME,
-
 
56
    VFS_OPENDIR,
-
 
57
    VFS_READDIR,
-
 
58
    VFS_CLOSEDIR,
-
 
59
    VFS_MKDIR,
-
 
60
    VFS_UNLINK,
-
 
61
    VFS_MOUNT,
53
    VFS_MOUNT,
62
    VFS_UNMOUNT,
54
    VFS_UNMOUNT,
63
    VFS_LAST_CMN,   /* keep this the last member of this enum */
55
    VFS_LAST_CMN,   /* keep this the last member of this enum */
64
} vfs_request_cmn_t;
56
} vfs_request_cmn_t;
65
 
57
 
66
typedef enum {
58
typedef enum {
67
    VFS_LOOKUP = VFS_LAST_CMN,
59
    VFS_LOOKUP = VFS_LAST_CMN,
-
 
60
    VFS_FREE,
68
    VFS_LAST_CLNT,  /* keep this the last member of this enum */
61
    VFS_LAST_CLNT,  /* keep this the last member of this enum */
69
} vfs_request_clnt_t;
62
} vfs_request_clnt_t;
70
 
63
 
71
typedef enum {
64
typedef enum {
72
    VFS_REGISTER = VFS_LAST_CMN,
65
    VFS_REGISTER = VFS_LAST_CMN,
-
 
66
    VFS_OPEN,
-
 
67
    VFS_CLOSE,
73
    VFS_SEEK,
68
    VFS_SEEK,
-
 
69
    VFS_MKDIR,
-
 
70
    VFS_UNLINK,
-
 
71
    VFS_RENAME,
74
    VFS_LAST_SRV,   /* keep this the last member of this enum */
72
    VFS_LAST_SRV,   /* keep this the last member of this enum */
75
} vfs_request_srv_t;
73
} vfs_request_srv_t;
76
 
74
 
77
 
75
 
78
/**
76
/**
79
 * An instance of this structure is associated with a particular FS operation.
77
 * An instance of this structure is associated with a particular FS operation.
80
 * It tells VFS if the FS supports the operation or maybe if a default one
78
 * It tells VFS if the FS supports the operation or maybe if a default one
81
 * should be used.
79
 * should be used.
82
 */
80
 */
83
typedef enum {
81
typedef enum {
84
    VFS_OP_NULL = 0,
82
    VFS_OP_NULL = 0,
85
    VFS_OP_DEFAULT,
83
    VFS_OP_DEFAULT,
86
    VFS_OP_DEFINED
84
    VFS_OP_DEFINED
87
} vfs_op_t;
85
} vfs_op_t;
88
 
86
 
89
#define FS_NAME_MAXLEN  20
87
#define FS_NAME_MAXLEN  20
90
 
88
 
91
/**
89
/**
92
 * A structure like this is passed to VFS by each individual FS upon its
90
 * A structure like this is passed to VFS by each individual FS upon its
93
 * registration. It assosiates a human-readable identifier with each
91
 * registration. It assosiates a human-readable identifier with each
94
 * registered FS. More importantly, through this structure, the FS announces
92
 * registered FS. More importantly, through this structure, the FS announces
95
 * what operations it supports.
93
 * what operations it supports.
96
 */
94
 */
97
typedef struct {
95
typedef struct {
98
    /** Unique identifier of the fs. */
96
    /** Unique identifier of the fs. */
99
    char name[FS_NAME_MAXLEN + 1];
97
    char name[FS_NAME_MAXLEN + 1];
100
   
98
   
101
    /** Operations. */
99
    /** Operations. */
102
    vfs_op_t ops[VFS_LAST_CLNT - VFS_FIRST];
100
    vfs_op_t ops[VFS_LAST_CLNT - VFS_FIRST];
103
} vfs_info_t;
101
} vfs_info_t;
104
 
102
 
105
/**
103
/**
106
 * A structure like this will be allocated for each registered file system.
104
 * A structure like this will be allocated for each registered file system.
107
 */
105
 */
108
typedef struct {
106
typedef struct {
109
    link_t fs_link;
107
    link_t fs_link;
110
    vfs_info_t vfs_info;
108
    vfs_info_t vfs_info;
111
    int fs_handle;
109
    int fs_handle;
112
    atomic_t phone_futex;   /**< Phone serializing futex. */
110
    atomic_t phone_futex;   /**< Phone serializing futex. */
113
    ipcarg_t phone;
111
    ipcarg_t phone;
114
} fs_info_t;
112
} fs_info_t;
115
 
113
 
116
/**
114
/**
117
 * VFS_PAIR uniquely represents a file system instance.
115
 * VFS_PAIR uniquely represents a file system instance.
118
 */
116
 */
119
#define VFS_PAIR    \
117
#define VFS_PAIR    \
120
    int fs_handle;  \
118
    int fs_handle;  \
121
    int dev_handle; 
119
    int dev_handle; 
122
 
120
 
123
/**
121
/**
124
 * VFS_TRIPLET uniquely identifies a file system node (e.g. directory, file) but
122
 * VFS_TRIPLET uniquely identifies a file system node (e.g. directory, file) but
125
 * doesn't contain any state. For a stateful structure, see vfs_node_t.
123
 * doesn't contain any state. For a stateful structure, see vfs_node_t.
126
 *
124
 *
127
 * @note    fs_handle, dev_handle and index are meant to be returned in one
125
 * @note    fs_handle, dev_handle and index are meant to be returned in one
128
 *      IPC reply.
126
 *      IPC reply.
129
 */
127
 */
130
#define VFS_TRIPLET \
128
#define VFS_TRIPLET \
131
    VFS_PAIR;   \
129
    VFS_PAIR;   \
132
    uint64_t index;
130
    uint64_t index;
133
 
131
 
134
typedef struct {
132
typedef struct {
135
    VFS_PAIR;
133
    VFS_PAIR;
136
} vfs_pair_t;
134
} vfs_pair_t;
137
 
135
 
138
typedef struct {
136
typedef struct {
139
    VFS_TRIPLET;
137
    VFS_TRIPLET;
140
} vfs_triplet_t;
138
} vfs_triplet_t;
141
 
139
 
142
/*
140
/*
143
 * Lookup flags.
141
 * Lookup flags.
144
 */
142
 */
145
/**
143
/**
146
 * Lookup will succeed only if the object is a regular file.  If L_CREATE is
144
 * Lookup will succeed only if the object is a regular file.  If L_CREATE is
147
 * specified, an empty file will be created. This flag is mutually exclusive
145
 * specified, an empty file will be created. This flag is mutually exclusive
148
 * with L_DIRECTORY.
146
 * with L_DIRECTORY.
149
 */
147
 */
150
#define L_FILE      1
148
#define L_FILE      1
151
/**
149
/**
152
 * Lookup wil succeed only if the object is a directory. If L_CREATE is
150
 * Lookup wil succeed only if the object is a directory. If L_CREATE is
153
 * specified, an empty directory will be created. This flag is mutually
151
 * specified, an empty directory will be created. This flag is mutually
154
 * exclusive with L_FILE.
152
 * exclusive with L_FILE.
155
 */
153
 */
156
#define L_DIRECTORY 2
154
#define L_DIRECTORY 2
157
/**
155
/**
158
 * When used with L_CREATE, L_EXCLUSIVE will cause the lookup to fail if the
156
 * When used with L_CREATE, L_EXCLUSIVE will cause the lookup to fail if the
159
 * object already exists. L_EXCLUSIVE is implied when L_DIRECTORY is used.
157
 * object already exists. L_EXCLUSIVE is implied when L_DIRECTORY is used.
160
 */
158
 */
161
#define L_EXCLUSIVE 4
159
#define L_EXCLUSIVE 4
162
/**
160
/**
163
 * L_CREATE is used for creating both regular files and directories.
161
 * L_CREATE is used for creating both regular files and directories.
164
 */
162
 */
165
#define L_CREATE    8
163
#define L_CREATE    8
166
/**
164
/**
167
 * L_DESTROY is used to remove leaves from the file system namespace. This flag
165
 * L_DESTROY is used to remove leaves from the file system namespace. This flag
168
 * cannot be passed directly by the client, but will be set by VFS during
166
 * cannot be passed directly by the client, but will be set by VFS during
169
 * VFS_UNLINK.
167
 * VFS_UNLINK.
170
 */
168
 */
171
#define L_DESTROY   16
169
#define L_DESTROY   16
172
 
170
 
173
typedef struct {
171
typedef struct {
174
    vfs_triplet_t triplet;
172
    vfs_triplet_t triplet;
175
    size_t size;
173
    size_t size;
176
    unsigned lnkcnt;
174
    unsigned lnkcnt;
177
} vfs_lookup_res_t;
175
} vfs_lookup_res_t;
178
 
176
 
179
/**
177
/**
180
 * Instances of this type represent an active, in-memory VFS node and any state
178
 * Instances of this type represent an active, in-memory VFS node and any state
181
 * which may be associated with it.
179
 * which may be associated with it.
182
 */
180
 */
183
typedef struct {
181
typedef struct {
184
    VFS_TRIPLET;        /**< Identity of the node. */
182
    VFS_TRIPLET;        /**< Identity of the node. */
185
 
183
 
186
    /**
184
    /**
187
     * Usage counter.  This includes, but is not limited to, all vfs_file_t
185
     * Usage counter.  This includes, but is not limited to, all vfs_file_t
188
     * structures that reference this node.
186
     * structures that reference this node.
189
     */
187
     */
190
    unsigned refcnt;
188
    unsigned refcnt;
191
   
189
   
192
    /** Number of names this node has in the file system namespace. */
190
    /** Number of names this node has in the file system namespace. */
193
    unsigned lnkcnt;
191
    unsigned lnkcnt;
194
 
192
 
195
    link_t nh_link;     /**< Node hash-table link. */
193
    link_t nh_link;     /**< Node hash-table link. */
196
    size_t size;        /**< Cached size of the file. */
194
    size_t size;        /**< Cached size of the file. */
197
 
195
 
198
    /**
196
    /**
199
     * Holding this rwlock prevents modifications of the node's contents.
197
     * Holding this rwlock prevents modifications of the node's contents.
200
     */
198
     */
201
    rwlock_t contents_rwlock;
199
    rwlock_t contents_rwlock;
202
} vfs_node_t;
200
} vfs_node_t;
203
 
201
 
204
/**
202
/**
205
 * Instances of this type represent an open file. If the file is opened by more
203
 * Instances of this type represent an open file. If the file is opened by more
206
 * than one task, there will be a separate structure allocated for each task.
204
 * than one task, there will be a separate structure allocated for each task.
207
 */
205
 */
208
typedef struct {
206
typedef struct {
209
    /** Serializes access to this open file. */
207
    /** Serializes access to this open file. */
210
    futex_t lock;
208
    futex_t lock;
211
 
209
 
212
    vfs_node_t *node;
210
    vfs_node_t *node;
213
   
211
   
214
    /** Number of file handles referencing this file. */
212
    /** Number of file handles referencing this file. */
215
    unsigned refcnt;
213
    unsigned refcnt;
216
 
214
 
217
    /** Append on write. */
215
    /** Append on write. */
218
    bool append;
216
    bool append;
219
 
217
 
220
    /** Current position in the file. */
218
    /** Current position in the file. */
221
    off_t pos;
219
    off_t pos;
222
} vfs_file_t;
220
} vfs_file_t;
223
 
221
 
224
extern link_t fs_head;      /**< List of registered file systems. */
222
extern link_t fs_head;      /**< List of registered file systems. */
225
 
223
 
226
extern vfs_triplet_t rootfs;    /**< Root node of the root file system. */
224
extern vfs_triplet_t rootfs;    /**< Root node of the root file system. */
227
 
225
 
228
#define MAX_PATH_LEN        (64 * 1024)
226
#define MAX_PATH_LEN        (64 * 1024)
229
 
227
 
230
#define PLB_SIZE        (2 * MAX_PATH_LEN)
228
#define PLB_SIZE        (2 * MAX_PATH_LEN)
231
 
229
 
232
/** Each instance of this type describes one path lookup in progress. */
230
/** Each instance of this type describes one path lookup in progress. */
233
typedef struct {
231
typedef struct {
234
    link_t  plb_link;   /**< Active PLB entries list link. */
232
    link_t  plb_link;   /**< Active PLB entries list link. */
235
    unsigned index;     /**< Index of the first character in PLB. */
233
    unsigned index;     /**< Index of the first character in PLB. */
236
    size_t len;     /**< Number of characters in this PLB entry. */
234
    size_t len;     /**< Number of characters in this PLB entry. */
237
} plb_entry_t;
235
} plb_entry_t;
238
 
236
 
239
extern atomic_t plb_futex;  /**< Futex protecting plb and plb_head. */
237
extern atomic_t plb_futex;  /**< Futex protecting plb and plb_head. */
240
extern uint8_t *plb;        /**< Path Lookup Buffer */
238
extern uint8_t *plb;        /**< Path Lookup Buffer */
241
extern link_t plb_head;     /**< List of active PLB entries. */
239
extern link_t plb_head;     /**< List of active PLB entries. */
242
 
240
 
243
/** Holding this rwlock prevents changes in file system namespace. */
241
/** Holding this rwlock prevents changes in file system namespace. */
244
extern rwlock_t namespace_rwlock;
242
extern rwlock_t namespace_rwlock;
245
 
243
 
246
extern int vfs_grab_phone(int);
244
extern int vfs_grab_phone(int);
247
extern void vfs_release_phone(int);
245
extern void vfs_release_phone(int);
248
 
246
 
249
extern int fs_name_to_handle(char *, bool);
247
extern int fs_name_to_handle(char *, bool);
250
 
248
 
251
extern int vfs_lookup_internal(char *, size_t, int, vfs_lookup_res_t *,
249
extern int vfs_lookup_internal(char *, size_t, int, vfs_lookup_res_t *,
252
    vfs_pair_t *);
250
    vfs_pair_t *);
253
 
251
 
254
extern bool vfs_nodes_init(void);
252
extern bool vfs_nodes_init(void);
255
extern vfs_node_t *vfs_node_get(vfs_lookup_res_t *);
253
extern vfs_node_t *vfs_node_get(vfs_lookup_res_t *);
256
extern void vfs_node_put(vfs_node_t *);
254
extern void vfs_node_put(vfs_node_t *);
257
 
255
 
258
#define MAX_OPEN_FILES  128
256
#define MAX_OPEN_FILES  128
259
 
257
 
260
extern bool vfs_files_init(void);
258
extern bool vfs_files_init(void);
261
extern vfs_file_t *vfs_file_get(int);
259
extern vfs_file_t *vfs_file_get(int);
262
extern int vfs_fd_alloc(void);
260
extern int vfs_fd_alloc(void);
263
extern void vfs_fd_free(int);
261
extern void vfs_fd_free(int);
264
 
262
 
265
extern void vfs_file_addref(vfs_file_t *);
263
extern void vfs_file_addref(vfs_file_t *);
266
extern void vfs_file_delref(vfs_file_t *);
264
extern void vfs_file_delref(vfs_file_t *);
267
 
265
 
268
extern void vfs_node_addref(vfs_node_t *);
266
extern void vfs_node_addref(vfs_node_t *);
269
extern void vfs_node_delref(vfs_node_t *);
267
extern void vfs_node_delref(vfs_node_t *);
270
 
268
 
271
extern void vfs_register(ipc_callid_t, ipc_call_t *);
269
extern void vfs_register(ipc_callid_t, ipc_call_t *);
272
extern void vfs_mount(ipc_callid_t, ipc_call_t *);
270
extern void vfs_mount(ipc_callid_t, ipc_call_t *);
273
extern void vfs_open(ipc_callid_t, ipc_call_t *);
271
extern void vfs_open(ipc_callid_t, ipc_call_t *);
274
extern void vfs_read(ipc_callid_t, ipc_call_t *);
272
extern void vfs_read(ipc_callid_t, ipc_call_t *);
275
extern void vfs_write(ipc_callid_t, ipc_call_t *);
273
extern void vfs_write(ipc_callid_t, ipc_call_t *);
276
extern void vfs_seek(ipc_callid_t, ipc_call_t *);
274
extern void vfs_seek(ipc_callid_t, ipc_call_t *);
277
extern void vfs_truncate(ipc_callid_t, ipc_call_t *);
275
extern void vfs_truncate(ipc_callid_t, ipc_call_t *);
278
extern void vfs_mkdir(ipc_callid_t, ipc_call_t *);
276
extern void vfs_mkdir(ipc_callid_t, ipc_call_t *);
279
 
277
 
280
#endif
278
#endif
281
 
279
 
282
/**
280
/**
283
 * @}
281
 * @}
284
 */
282
 */
285
 
283