Subversion Repositories HelenOS

Rev

Rev 3307 | Rev 3593 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
2006 decky 1
/*
2071 jermar 2
 * Copyright (c) 2006 Martin Decky
2690 jermar 3
 * Copyright (c) 2008 Jakub Jermar
2006 decky 4
 * All rights reserved.
5
 *
6
 * Redistribution and use in source and binary forms, with or without
7
 * modification, are permitted provided that the following conditions
8
 * are met:
9
 *
10
 * - Redistributions of source code must retain the above copyright
11
 *   notice, this list of conditions and the following disclaimer.
12
 * - Redistributions in binary form must reproduce the above copyright
13
 *   notice, this list of conditions and the following disclaimer in the
14
 *   documentation and/or other materials provided with the distribution.
15
 * - The name of the author may not be used to endorse or promote products
16
 *   derived from this software without specific prior written permission.
17
 *
18
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28
 */
29
 
30
/** @addtogroup fs
31
 * @{
32
 */
33
 
34
/**
2529 jermar 35
 * @file    fat.c
36
 * @brief   FAT file system driver for HelenOS.
2006 decky 37
 */
38
 
2627 jermar 39
#include "fat.h"
2529 jermar 40
#include <ipc/ipc.h>
41
#include <ipc/services.h>
2531 jermar 42
#include <async.h>
2529 jermar 43
#include <errno.h>
44
#include <unistd.h>
2536 jermar 45
#include <stdio.h>
2643 jermar 46
#include <libfs.h>
2529 jermar 47
#include "../../vfs/vfs.h"
2006 decky 48
 
2532 jermar 49
 
2529 jermar 50
vfs_info_t fat_vfs_info = {
51
    .name = "fat",
52
    .ops = {
53
        [IPC_METHOD_TO_VFS_OP(VFS_LOOKUP)] = VFS_OP_DEFINED,
54
        [IPC_METHOD_TO_VFS_OP(VFS_READ)] = VFS_OP_DEFINED,
55
        [IPC_METHOD_TO_VFS_OP(VFS_WRITE)] = VFS_OP_NULL,
2690 jermar 56
        [IPC_METHOD_TO_VFS_OP(VFS_TRUNCATE)] = VFS_OP_NULL,
57
        [IPC_METHOD_TO_VFS_OP(VFS_MOUNT)] = VFS_OP_NULL,
3110 jermar 58
        [IPC_METHOD_TO_VFS_OP(VFS_MOUNTED)] = VFS_OP_DEFINED,
2690 jermar 59
        [IPC_METHOD_TO_VFS_OP(VFS_UNMOUNT)] = VFS_OP_NULL,
2529 jermar 60
    }
61
};
62
 
2643 jermar 63
fs_reg_t fat_reg;
2543 jermar 64
 
2536 jermar 65
/**
66
 * This connection fibril processes VFS requests from VFS.
67
 *
68
 * In order to support simultaneous VFS requests, our design is as follows.
69
 * The connection fibril accepts VFS requests from VFS. If there is only one
70
 * instance of the fibril, VFS will need to serialize all VFS requests it sends
71
 * to FAT. To overcome this bottleneck, VFS can send FAT the IPC_M_CONNECT_ME_TO
72
 * call. In that case, a new connection fibril will be created, which in turn
73
 * will accept the call. Thus, a new phone will be opened for VFS.
74
 *
75
 * There are few issues with this arrangement. First, VFS can run out of
76
 * available phones. In that case, VFS can close some other phones or use one
2627 jermar 77
 * phone for more serialized requests. Similarily, FAT can refuse to duplicate
2536 jermar 78
 * the connection. VFS should then just make use of already existing phones and
79
 * route its requests through them. To avoid paying the fibril creation price
80
 * upon each request, FAT might want to keep the connections open after the
81
 * request has been completed.
2531 jermar 82
 */
2536 jermar 83
static void fat_connection(ipc_callid_t iid, ipc_call_t *icall)
2531 jermar 84
{
2536 jermar 85
    if (iid) {
86
        /*
87
         * This only happens for connections opened by
88
         * IPC_M_CONNECT_ME_TO calls as opposed to callback connections
89
         * created by IPC_M_CONNECT_TO_ME.
90
         */
2619 jermar 91
        ipc_answer_0(iid, EOK);
2536 jermar 92
    }
93
 
94
    dprintf("VFS-FAT connection established.\n");
2531 jermar 95
    while (1) {
96
        ipc_callid_t callid;
97
        ipc_call_t call;
98
 
99
        callid = async_get_call(&call);
2536 jermar 100
        switch  (IPC_GET_METHOD(call)) {
3110 jermar 101
        case VFS_MOUNTED:
102
            fat_mounted(callid, &call);
103
            break;
104
        case VFS_MOUNT:
105
            fat_mount(callid, &call);
106
            break;
2627 jermar 107
        case VFS_LOOKUP:
108
            fat_lookup(callid, &call);
109
            break;
3307 jermar 110
        case VFS_READ:
111
            fat_read(callid, &call);
112
            break;
2536 jermar 113
        default:
2619 jermar 114
            ipc_answer_0(callid, ENOTSUP);
2536 jermar 115
            break;
116
        }
2531 jermar 117
    }
118
}
119
 
2006 decky 120
int main(int argc, char **argv)
121
{
2532 jermar 122
    int vfs_phone;
3110 jermar 123
    int rc;
2529 jermar 124
 
2532 jermar 125
    printf("FAT: HelenOS FAT file system server.\n");
126
 
3110 jermar 127
    rc = fat_idx_init();
128
    if (rc != EOK)
129
        goto err;
130
 
2635 cejka 131
    vfs_phone = ipc_connect_me_to(PHONE_NS, SERVICE_VFS, 0, 0);
2532 jermar 132
    while (vfs_phone < EOK) {
2529 jermar 133
        usleep(10000);
2635 cejka 134
        vfs_phone = ipc_connect_me_to(PHONE_NS, SERVICE_VFS, 0, 0);
2529 jermar 135
    }
136
 
2643 jermar 137
    rc = fs_register(vfs_phone, &fat_reg, &fat_vfs_info, fat_connection);
2531 jermar 138
    if (rc != EOK) {
3110 jermar 139
        fat_idx_fini();
140
        goto err;
2531 jermar 141
    }
2536 jermar 142
 
2644 jermar 143
    dprintf("FAT filesystem registered, fs_handle=%d.\n",
144
        fat_reg.fs_handle);
2532 jermar 145
 
2568 jermar 146
    async_manager();
2534 jermar 147
    /* not reached */
2006 decky 148
    return 0;
3110 jermar 149
 
150
err:
151
    printf("Failed to register the FAT file system (%d)\n", rc);
152
    return rc;
2006 decky 153
}
154
 
155
/**
156
 * @}
157
 */