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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.
13
 *   documentation and/or other materials provided with the distribution.
14
 * - 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
15
 *   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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 *
16
 *
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
18
 * 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.
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20
 * 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
25
 * (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
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
 */
27
 */
28
 
28
 
29
/** @addtogroup fs
29
/** @addtogroup fs
30
 * @{
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 <futex.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_READ = VFS_FIRST,
50
    VFS_READ = VFS_FIRST,
51
    VFS_WRITE,
51
    VFS_WRITE,
52
    VFS_TRUNCATE,
52
    VFS_TRUNCATE,
53
    VFS_MOUNT,
53
    VFS_MOUNT,
54
    VFS_UNMOUNT,
54
    VFS_UNMOUNT,
55
    VFS_LAST_CMN,   /* keep this the last member of this enum */
55
    VFS_LAST_CMN,   /* keep this the last member of this enum */
56
} vfs_request_cmn_t;
56
} vfs_request_cmn_t;
57
 
57
 
58
typedef enum {
58
typedef enum {
59
    VFS_LOOKUP = VFS_LAST_CMN,
59
    VFS_LOOKUP = VFS_LAST_CMN,
60
    VFS_DESTROY,
60
    VFS_DESTROY,
61
    VFS_LAST_CLNT,  /* keep this the last member of this enum */
61
    VFS_LAST_CLNT,  /* keep this the last member of this enum */
62
} vfs_request_clnt_t;
62
} vfs_request_clnt_t;
63
 
63
 
64
typedef enum {
64
typedef enum {
65
    VFS_REGISTER = VFS_LAST_CMN,
65
    VFS_REGISTER = VFS_LAST_CMN,
66
    VFS_OPEN,
66
    VFS_OPEN,
67
    VFS_CLOSE,
67
    VFS_CLOSE,
68
    VFS_SEEK,
68
    VFS_SEEK,
69
    VFS_MKDIR,
69
    VFS_MKDIR,
70
    VFS_UNLINK,
70
    VFS_UNLINK,
71
    VFS_RENAME,
71
    VFS_RENAME,
72
    VFS_LAST_SRV,   /* keep this the last member of this enum */
72
    VFS_LAST_SRV,   /* keep this the last member of this enum */
73
} vfs_request_srv_t;
73
} vfs_request_srv_t;
74
 
74
 
75
 
75
 
76
/**
76
/**
77
 * 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.
78
 * 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
79
 * should be used.
79
 * should be used.
80
 */
80
 */
81
typedef enum {
81
typedef enum {
82
    VFS_OP_NULL = 0,
82
    VFS_OP_NULL = 0,
83
    VFS_OP_DEFAULT,
83
    VFS_OP_DEFAULT,
84
    VFS_OP_DEFINED
84
    VFS_OP_DEFINED
85
} vfs_op_t;
85
} vfs_op_t;
86
 
86
 
87
#define FS_NAME_MAXLEN  20
87
#define FS_NAME_MAXLEN  20
88
 
88
 
89
/**
89
/**
90
 * 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
91
 * registration. It assosiates a human-readable identifier with each
91
 * registration. It assosiates a human-readable identifier with each
92
 * registered FS. More importantly, through this structure, the FS announces
92
 * registered FS. More importantly, through this structure, the FS announces
93
 * what operations it supports.
93
 * what operations it supports.
94
 */
94
 */
95
typedef struct {
95
typedef struct {
96
    /** Unique identifier of the fs. */
96
    /** Unique identifier of the fs. */
97
    char name[FS_NAME_MAXLEN + 1];
97
    char name[FS_NAME_MAXLEN + 1];
98
   
98
   
99
    /** Operations. */
99
    /** Operations. */
100
    vfs_op_t ops[VFS_LAST_CLNT - VFS_FIRST];
100
    vfs_op_t ops[VFS_LAST_CLNT - VFS_FIRST];
101
} vfs_info_t;
101
} vfs_info_t;
102
 
102
 
103
/**
103
/**
104
 * 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.
105
 */
105
 */
106
typedef struct {
106
typedef struct {
107
    link_t fs_link;
107
    link_t fs_link;
108
    vfs_info_t vfs_info;
108
    vfs_info_t vfs_info;
109
    int fs_handle;
109
    int fs_handle;
110
    atomic_t phone_futex;   /**< Phone serializing futex. */
110
    futex_t phone_futex;    /**< Phone serializing futex. */
111
    ipcarg_t phone;
111
    ipcarg_t phone;
112
} fs_info_t;
112
} fs_info_t;
113
 
113
 
114
/**
114
/**
115
 * VFS_PAIR uniquely represents a file system instance.
115
 * VFS_PAIR uniquely represents a file system instance.
116
 */
116
 */
117
#define VFS_PAIR    \
117
#define VFS_PAIR    \
118
    int fs_handle;  \
118
    int fs_handle;  \
119
    int dev_handle; 
119
    int dev_handle; 
120
 
120
 
121
/**
121
/**
122
 * 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
123
 * 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.
124
 *
124
 *
125
 * @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
126
 *      IPC reply.
126
 *      IPC reply.
127
 */
127
 */
128
#define VFS_TRIPLET \
128
#define VFS_TRIPLET \
129
    VFS_PAIR;   \
129
    VFS_PAIR;   \
130
    uint64_t index;
130
    uint64_t index;
131
 
131
 
132
typedef struct {
132
typedef struct {
133
    VFS_PAIR;
133
    VFS_PAIR;
134
} vfs_pair_t;
134
} vfs_pair_t;
135
 
135
 
136
typedef struct {
136
typedef struct {
137
    VFS_TRIPLET;
137
    VFS_TRIPLET;
138
} vfs_triplet_t;
138
} vfs_triplet_t;
139
 
139
 
140
/*
140
/*
141
 * Lookup flags.
141
 * Lookup flags.
142
 */
142
 */
143
/**
143
/**
144
 * No lookup flags used.
144
 * No lookup flags used.
145
 */
145
 */
146
#define L_NONE      0
146
#define L_NONE      0
147
/**
147
/**
148
 * Lookup will succeed only if the object is a regular file.  If L_CREATE is
148
 * Lookup will succeed only if the object is a regular file.  If L_CREATE is
149
 * specified, an empty file will be created. This flag is mutually exclusive
149
 * specified, an empty file will be created. This flag is mutually exclusive
150
 * with L_DIRECTORY.
150
 * with L_DIRECTORY.
151
 */
151
 */
152
#define L_FILE      1
152
#define L_FILE      1
153
/**
153
/**
154
 * Lookup wil succeed only if the object is a directory. If L_CREATE is
154
 * Lookup wil succeed only if the object is a directory. If L_CREATE is
155
 * specified, an empty directory will be created. This flag is mutually
155
 * specified, an empty directory will be created. This flag is mutually
156
 * exclusive with L_FILE.
156
 * exclusive with L_FILE.
157
 */
157
 */
158
#define L_DIRECTORY 2
158
#define L_DIRECTORY 2
159
/**
159
/**
160
 * When used with L_CREATE, L_EXCLUSIVE will cause the lookup to fail if the
160
 * When used with L_CREATE, L_EXCLUSIVE will cause the lookup to fail if the
161
 * object already exists. L_EXCLUSIVE is implied when L_DIRECTORY is used.
161
 * object already exists. L_EXCLUSIVE is implied when L_DIRECTORY is used.
162
 */
162
 */
163
#define L_EXCLUSIVE 4
163
#define L_EXCLUSIVE 4
164
/**
164
/**
165
 * L_CREATE is used for creating both regular files and directories.
165
 * L_CREATE is used for creating both regular files and directories.
166
 */
166
 */
167
#define L_CREATE    8
167
#define L_CREATE    8
168
/**
168
/**
169
 * L_LINK is used for linking to an already existing nodes.
169
 * L_LINK is used for linking to an already existing nodes.
170
 */
170
 */
171
#define L_LINK      16
171
#define L_LINK      16
172
/**
172
/**
173
 * L_UNLINK is used to remove leaves from the file system namespace. This flag
173
 * L_UNLINK is used to remove leaves from the file system namespace. This flag
174
 * cannot be passed directly by the client, but will be set by VFS during
174
 * cannot be passed directly by the client, but will be set by VFS during
175
 * VFS_UNLINK.
175
 * VFS_UNLINK.
176
 */
176
 */
177
#define L_UNLINK    32  
177
#define L_UNLINK    32  
178
/**
178
/**
179
 * L_PARENT performs a lookup but returns the triplet of the parent node.
179
 * L_PARENT performs a lookup but returns the triplet of the parent node.
180
 * This flag may not be combined with any other lookup flag.
180
 * This flag may not be combined with any other lookup flag.
181
 */
181
 */
182
#define L_PARENT    64  
182
#define L_PARENT    64  
183
 
183
 
184
typedef struct {
184
typedef struct {
185
    vfs_triplet_t triplet;
185
    vfs_triplet_t triplet;
186
    size_t size;
186
    size_t size;
187
    unsigned lnkcnt;
187
    unsigned lnkcnt;
188
} vfs_lookup_res_t;
188
} vfs_lookup_res_t;
189
 
189
 
190
/**
190
/**
191
 * Instances of this type represent an active, in-memory VFS node and any state
191
 * Instances of this type represent an active, in-memory VFS node and any state
192
 * which may be associated with it.
192
 * which may be associated with it.
193
 */
193
 */
194
typedef struct {
194
typedef struct {
195
    VFS_TRIPLET;        /**< Identity of the node. */
195
    VFS_TRIPLET;        /**< Identity of the node. */
196
 
196
 
197
    /**
197
    /**
198
     * Usage counter.  This includes, but is not limited to, all vfs_file_t
198
     * Usage counter.  This includes, but is not limited to, all vfs_file_t
199
     * structures that reference this node.
199
     * structures that reference this node.
200
     */
200
     */
201
    unsigned refcnt;
201
    unsigned refcnt;
202
   
202
   
203
    /** Number of names this node has in the file system namespace. */
203
    /** Number of names this node has in the file system namespace. */
204
    unsigned lnkcnt;
204
    unsigned lnkcnt;
205
 
205
 
206
    link_t nh_link;     /**< Node hash-table link. */
206
    link_t nh_link;     /**< Node hash-table link. */
207
    size_t size;        /**< Cached size of the file. */
207
    size_t size;        /**< Cached size of the file. */
208
 
208
 
209
    /**
209
    /**
210
     * Holding this rwlock prevents modifications of the node's contents.
210
     * Holding this rwlock prevents modifications of the node's contents.
211
     */
211
     */
212
    rwlock_t contents_rwlock;
212
    rwlock_t contents_rwlock;
213
} vfs_node_t;
213
} vfs_node_t;
214
 
214
 
215
/**
215
/**
216
 * Instances of this type represent an open file. If the file is opened by more
216
 * Instances of this type represent an open file. If the file is opened by more
217
 * than one task, there will be a separate structure allocated for each task.
217
 * than one task, there will be a separate structure allocated for each task.
218
 */
218
 */
219
typedef struct {
219
typedef struct {
220
    /** Serializes access to this open file. */
220
    /** Serializes access to this open file. */
221
    futex_t lock;
221
    futex_t lock;
222
 
222
 
223
    vfs_node_t *node;
223
    vfs_node_t *node;
224
   
224
   
225
    /** Number of file handles referencing this file. */
225
    /** Number of file handles referencing this file. */
226
    unsigned refcnt;
226
    unsigned refcnt;
227
 
227
 
228
    /** Append on write. */
228
    /** Append on write. */
229
    bool append;
229
    bool append;
230
 
230
 
231
    /** Current position in the file. */
231
    /** Current position in the file. */
232
    off_t pos;
232
    off_t pos;
233
} vfs_file_t;
233
} vfs_file_t;
234
 
234
 
-
 
235
extern futex_t nodes_futex;
-
 
236
 
235
extern link_t fs_head;      /**< List of registered file systems. */
237
extern link_t fs_head;      /**< List of registered file systems. */
236
 
238
 
237
extern vfs_triplet_t rootfs;    /**< Root node of the root file system. */
239
extern vfs_triplet_t rootfs;    /**< Root node of the root file system. */
238
 
240
 
239
#define MAX_PATH_LEN        (64 * 1024)
241
#define MAX_PATH_LEN        (64 * 1024)
240
 
242
 
241
#define PLB_SIZE        (2 * MAX_PATH_LEN)
243
#define PLB_SIZE        (2 * MAX_PATH_LEN)
242
 
244
 
243
/** Each instance of this type describes one path lookup in progress. */
245
/** Each instance of this type describes one path lookup in progress. */
244
typedef struct {
246
typedef struct {
245
    link_t  plb_link;   /**< Active PLB entries list link. */
247
    link_t  plb_link;   /**< Active PLB entries list link. */
246
    unsigned index;     /**< Index of the first character in PLB. */
248
    unsigned index;     /**< Index of the first character in PLB. */
247
    size_t len;     /**< Number of characters in this PLB entry. */
249
    size_t len;     /**< Number of characters in this PLB entry. */
248
} plb_entry_t;
250
} plb_entry_t;
249
 
251
 
250
extern atomic_t plb_futex;  /**< Futex protecting plb and plb_head. */
252
extern futex_t plb_futex;   /**< Futex protecting plb and plb_head. */
251
extern uint8_t *plb;        /**< Path Lookup Buffer */
253
extern uint8_t *plb;        /**< Path Lookup Buffer */
252
extern link_t plb_head;     /**< List of active PLB entries. */
254
extern link_t plb_head;     /**< List of active PLB entries. */
253
 
255
 
254
/** Holding this rwlock prevents changes in file system namespace. */
256
/** Holding this rwlock prevents changes in file system namespace. */
255
extern rwlock_t namespace_rwlock;
257
extern rwlock_t namespace_rwlock;
256
 
258
 
257
extern int vfs_grab_phone(int);
259
extern int vfs_grab_phone(int);
258
extern void vfs_release_phone(int);
260
extern void vfs_release_phone(int);
259
 
261
 
260
extern int fs_name_to_handle(char *, bool);
262
extern int fs_name_to_handle(char *, bool);
261
 
263
 
262
extern int vfs_lookup_internal(char *, int, vfs_lookup_res_t *, vfs_pair_t *,
264
extern int vfs_lookup_internal(char *, int, vfs_lookup_res_t *, vfs_pair_t *,
263
    ...);
265
    ...);
264
 
266
 
265
extern bool vfs_nodes_init(void);
267
extern bool vfs_nodes_init(void);
266
extern vfs_node_t *vfs_node_get(vfs_lookup_res_t *);
268
extern vfs_node_t *vfs_node_get(vfs_lookup_res_t *);
267
extern void vfs_node_put(vfs_node_t *);
269
extern void vfs_node_put(vfs_node_t *);
268
 
270
 
269
#define MAX_OPEN_FILES  128
271
#define MAX_OPEN_FILES  128
270
 
272
 
271
extern bool vfs_files_init(void);
273
extern bool vfs_files_init(void);
272
extern vfs_file_t *vfs_file_get(int);
274
extern vfs_file_t *vfs_file_get(int);
273
extern int vfs_fd_alloc(void);
275
extern int vfs_fd_alloc(void);
274
extern void vfs_fd_free(int);
276
extern void vfs_fd_free(int);
275
 
277
 
276
extern void vfs_file_addref(vfs_file_t *);
278
extern void vfs_file_addref(vfs_file_t *);
277
extern void vfs_file_delref(vfs_file_t *);
279
extern void vfs_file_delref(vfs_file_t *);
278
 
280
 
279
extern void vfs_node_addref(vfs_node_t *);
281
extern void vfs_node_addref(vfs_node_t *);
280
extern void vfs_node_delref(vfs_node_t *);
282
extern void vfs_node_delref(vfs_node_t *);
281
 
283
 
282
extern void vfs_register(ipc_callid_t, ipc_call_t *);
284
extern void vfs_register(ipc_callid_t, ipc_call_t *);
283
extern void vfs_mount(ipc_callid_t, ipc_call_t *);
285
extern void vfs_mount(ipc_callid_t, ipc_call_t *);
284
extern void vfs_open(ipc_callid_t, ipc_call_t *);
286
extern void vfs_open(ipc_callid_t, ipc_call_t *);
285
extern void vfs_close(ipc_callid_t, ipc_call_t *);
287
extern void vfs_close(ipc_callid_t, ipc_call_t *);
286
extern void vfs_read(ipc_callid_t, ipc_call_t *);
288
extern void vfs_read(ipc_callid_t, ipc_call_t *);
287
extern void vfs_write(ipc_callid_t, ipc_call_t *);
289
extern void vfs_write(ipc_callid_t, ipc_call_t *);
288
extern void vfs_seek(ipc_callid_t, ipc_call_t *);
290
extern void vfs_seek(ipc_callid_t, ipc_call_t *);
289
extern void vfs_truncate(ipc_callid_t, ipc_call_t *);
291
extern void vfs_truncate(ipc_callid_t, ipc_call_t *);
290
extern void vfs_mkdir(ipc_callid_t, ipc_call_t *);
292
extern void vfs_mkdir(ipc_callid_t, ipc_call_t *);
291
extern void vfs_unlink(ipc_callid_t, ipc_call_t *);
293
extern void vfs_unlink(ipc_callid_t, ipc_call_t *);
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extern void vfs_rename(ipc_callid_t, ipc_call_t *);
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extern void vfs_rename(ipc_callid_t, ipc_call_t *);
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#endif
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#endif
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/**
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/**
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 * @}
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 * @}
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 */
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 */
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