Subversion Repositories HelenOS

Rev

Rev 2540 | Rev 2544 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
2520 jermar 1
/*
2
 * Copyright (c) 2007 Jakub Jermar
3
 * All rights reserved.
4
 *
5
 * Redistribution and use in source and binary forms, with or without
6
 * modification, are permitted provided that the following conditions
7
 * are met:
8
 *
9
 * - Redistributions of source code must retain the above copyright
10
 *   notice, this list of conditions and the following disclaimer.
11
 * - Redistributions in binary form must reproduce the above copyright
12
 *   notice, this list of conditions and the following disclaimer in the
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
15
 *   derived from this software without specific prior written permission.
16
 *
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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.
27
 */
28
 
29
/** @addtogroup fs
30
 * @{
31
 */
32
 
33
#ifndef VFS_VFS_H_
34
#define VFS_VFS_H_
35
 
2523 jermar 36
#include <ipc/ipc.h>
2529 jermar 37
#include <libadt/list.h>
2540 jermar 38
#include <atomic.h>
2542 jermar 39
#include <sys/types.h>
2523 jermar 40
 
2535 jermar 41
#define dprintf(...)    printf(__VA_ARGS__)
42
 
2523 jermar 43
#define VFS_FIRST   FIRST_USER_METHOD
44
 
2526 jermar 45
#define IPC_METHOD_TO_VFS_OP(m) ((m) - VFS_FIRST)   
46
 
2520 jermar 47
typedef enum {
2523 jermar 48
    VFS_REGISTER = VFS_FIRST,
2520 jermar 49
    VFS_MOUNT,
50
    VFS_UNMOUNT,
2527 jermar 51
    VFS_LOOKUP,
2521 jermar 52
    VFS_OPEN,
2523 jermar 53
    VFS_CREATE,
54
    VFS_CLOSE,
55
    VFS_READ,
56
    VFS_WRITE,
57
    VFS_SEEK,
2521 jermar 58
    VFS_LAST,       /* keep this the last member of the enum */
2520 jermar 59
} vfs_request_t;
60
 
2521 jermar 61
 
62
/**
63
 * An instance of this structure is associated with a particular FS operation.
64
 * It tells VFS if the FS supports the operation or maybe if a default one
65
 * should be used.
66
 */
67
typedef enum {
2523 jermar 68
    VFS_OP_NULL = 0,
2521 jermar 69
    VFS_OP_DEFAULT,
70
    VFS_OP_DEFINED
71
} vfs_op_t;
72
 
73
#define FS_NAME_MAXLEN  20
74
 
75
/**
76
 * A structure like this is passed to VFS by each individual FS upon its
77
 * registration. It assosiates a human-readable identifier with each
78
 * registered FS. More importantly, through this structure, the FS announces
79
 * what operations it supports.
80
 */
81
typedef struct {
2523 jermar 82
    /** Unique identifier of the fs. */
2526 jermar 83
    char name[FS_NAME_MAXLEN];
2523 jermar 84
 
85
    /** Operations. */
86
    vfs_op_t ops[VFS_LAST - VFS_FIRST];
2521 jermar 87
} vfs_info_t;
88
 
2540 jermar 89
/**
90
 * A structure like this will be allocated for each registered file system.
91
 */
2526 jermar 92
typedef struct {
93
    link_t fs_link;
94
    vfs_info_t vfs_info;
2527 jermar 95
    ipcarg_t phone;
2526 jermar 96
} fs_info_t;
97
 
2540 jermar 98
/**
99
 * Instances of this type represent a file system node (e.g. directory, file).
100
 * They are abstracted away from any file system implementation and contain just
101
 * enough bits to uniquely identify the object in its file system instance.
102
 *
103
 * @note    fs_handle, dev_handle and index are meant to be returned in one
104
 *      IPC reply.
105
 */
106
typedef struct {
107
    int fs_handle;      /**< Global file system ID. */
108
    int dev_handle;     /**< Global mount device devno. */
109
    uint64_t index;     /**< Index of the node on its file system. */
110
} vfs_node_t;
111
 
112
/**
113
 * Instances of this type represent an open file. If the file is opened by more
114
 * than one task, there will be a separate structure allocated for each task.
115
 */
116
typedef struct {
117
    vfs_node_t *node;
118
 
119
    /** Number of file handles referencing this file. */
120
    atomic_t refcnt;
121
 
122
    /** Current position in the file. */
123
    off_t pos;
124
} vfs_file_t;
125
 
2542 jermar 126
extern link_t fs_head;      /**< List of registered file systems. */
2535 jermar 127
 
2542 jermar 128
extern vfs_node_t *rootfs;  /**< Root node of the root file system. */
2535 jermar 129
 
2542 jermar 130
#define MAX_PATH_LEN        (64 * 1024)
131
 
132
#define PLB_SIZE        (2 * MAX_PATH_LEN)
133
 
134
/** Each instance of this type describes one path lookup in progress. */
135
typedef struct {
136
    link_t  plb_link;   /**< Active PLB entries list link. */
137
    unsigned index;     /**< Index of the first character in PLB. */
138
    size_t len;     /**< Number of characters in this PLB entry. */
139
} plb_entry_t;
140
 
141
extern atomic_t plb_futex;  /**< Futex protecting plb and plb_head. */
142
extern uint8_t *plb;        /**< Path Lookup Buffer */
143
extern link_t plb_head;     /**< List of active PLB entries. */
144
 
145
extern void vfs_register(ipc_callid_t, ipc_call_t *);
146
extern void vfs_lookup(ipc_callid_t, ipc_call_t *);
147
 
2520 jermar 148
#endif
149
 
150
/**
151
 * @}
2523 jermar 152
 */