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2642 jermar 1
/*
4420 trochtova 2
 * Copyright (c) 2009 Jakub Jermar
2642 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 libfs
30
 * @{
31
 */
32
/**
33
 * @file
34
 * Glue code which is commonod to all FS implementations.
35
 */
36
 
37
#include "libfs.h" 
2643 jermar 38
#include "../../srv/vfs/vfs.h"
39
#include <errno.h>
40
#include <async.h>
41
#include <ipc/ipc.h>
42
#include <as.h>
2747 jermar 43
#include <assert.h>
44
#include <dirent.h>
4537 trochtova 45
#include <mem.h>
2642 jermar 46
 
2643 jermar 47
/** Register file system server.
48
 *
49
 * This function abstracts away the tedious registration protocol from
50
 * file system implementations and lets them to reuse this registration glue
51
 * code.
52
 *
53
 * @param vfs_phone Open phone for communication with VFS.
54
 * @param reg       File system registration structure. It will be
55
 *          initialized by this function.
56
 * @param info      VFS info structure supplied by the file system
57
 *          implementation.
58
 * @param conn      Connection fibril for handling all calls originating in
59
 *          VFS.
60
 *
61
 * @return      EOK on success or a non-zero error code on errror.
62
 */
63
int fs_register(int vfs_phone, fs_reg_t *reg, vfs_info_t *info,
64
    async_client_conn_t conn)
65
{
66
    /*
67
     * Tell VFS that we are here and want to get registered.
68
     * We use the async framework because VFS will answer the request
69
     * out-of-order, when it knows that the operation succeeded or failed.
70
     */
71
    ipc_call_t answer;
72
    aid_t req = async_send_0(vfs_phone, VFS_REGISTER, &answer);
73
 
74
    /*
75
     * Send our VFS info structure to VFS.
76
     */
2678 jermar 77
    int rc = ipc_data_write_start(vfs_phone, info, sizeof(*info));
2643 jermar 78
    if (rc != EOK) {
79
        async_wait_for(req, NULL);
80
        return rc;
81
    }
82
 
83
    /*
84
     * Ask VFS for callback connection.
85
     */
86
    ipc_connect_to_me(vfs_phone, 0, 0, 0, &reg->vfs_phonehash);
87
 
88
    /*
89
     * Allocate piece of address space for PLB.
90
     */
91
    reg->plb_ro = as_get_mappable_page(PLB_SIZE);
92
    if (!reg->plb_ro) {
93
        async_wait_for(req, NULL);
94
        return ENOMEM;
95
    }
96
 
97
    /*
98
     * Request sharing the Path Lookup Buffer with VFS.
99
     */
2678 jermar 100
    rc = ipc_share_in_start_0_0(vfs_phone, reg->plb_ro, PLB_SIZE);
2643 jermar 101
    if (rc) {
102
        async_wait_for(req, NULL);
103
        return rc;
104
    }
105
 
106
    /*
107
     * Pick up the answer for the request to the VFS_REQUEST call.
108
     */
109
    async_wait_for(req, NULL);
110
    reg->fs_handle = (int) IPC_GET_ARG1(answer);
111
 
112
    /*
113
     * Create a connection fibril to handle the callback connection.
114
     */
115
    async_new_connection(reg->vfs_phonehash, 0, NULL, conn);
116
 
117
    /*
118
     * Tell the async framework that other connections are to be handled by
119
     * the same connection fibril as well.
120
     */
121
    async_set_client_connection(conn);
122
 
123
    return IPC_GET_RETVAL(answer);
124
}
125
 
4420 trochtova 126
void fs_node_initialize(fs_node_t *fn)
127
{
128
    memset(fn, 0, sizeof(fs_node_t));
129
}
130
 
4439 trochtova 131
void libfs_mount(libfs_ops_t *ops, fs_handle_t fs_handle, ipc_callid_t rid,
132
    ipc_call_t *request)
4420 trochtova 133
{
134
    dev_handle_t mp_dev_handle = (dev_handle_t) IPC_GET_ARG1(*request);
135
    fs_index_t mp_fs_index = (fs_index_t) IPC_GET_ARG2(*request);
136
    fs_handle_t mr_fs_handle = (fs_handle_t) IPC_GET_ARG3(*request);
137
    dev_handle_t mr_dev_handle = (dev_handle_t) IPC_GET_ARG4(*request);
138
    int res;
139
    ipcarg_t rc;
140
 
141
    ipc_call_t call;
142
    ipc_callid_t callid;
143
 
144
    /* accept the phone */
145
    callid = async_get_call(&call);
146
    int mountee_phone = (int)IPC_GET_ARG1(call);
147
    if ((IPC_GET_METHOD(call) != IPC_M_CONNECTION_CLONE) ||
148
        mountee_phone < 0) {
149
        ipc_answer_0(callid, EINVAL);
150
        ipc_answer_0(rid, EINVAL);
151
        return;
152
    }
153
    ipc_answer_0(callid, EOK);  /* acknowledge the mountee_phone */
154
 
155
    res = ipc_data_write_receive(&callid, NULL);
156
    if (!res) {
157
        ipc_hangup(mountee_phone);
158
        ipc_answer_0(callid, EINVAL);
159
        ipc_answer_0(rid, EINVAL);
160
        return;
161
    }
162
 
163
    fs_node_t *fn = ops->node_get(mp_dev_handle, mp_fs_index);
164
    if (!fn) {
165
        ipc_hangup(mountee_phone);
166
        ipc_answer_0(callid, ENOENT);
167
        ipc_answer_0(rid, ENOENT);
168
        return;
169
    }
170
 
171
    if (fn->mp_data.mp_active) {
172
        ipc_hangup(mountee_phone);
173
        ops->node_put(fn);
174
        ipc_answer_0(callid, EBUSY);
175
        ipc_answer_0(rid, EBUSY);
176
        return;
177
    }
178
 
179
    rc = async_req_0_0(mountee_phone, IPC_M_CONNECT_ME);
180
    if (rc != 0) {
181
        ipc_hangup(mountee_phone);
182
        ops->node_put(fn);
183
        ipc_answer_0(callid, rc);
184
        ipc_answer_0(rid, rc);
185
        return;
186
    }
187
 
188
    ipc_call_t answer;
189
    aid_t msg = async_send_1(mountee_phone, VFS_MOUNTED, mr_dev_handle,
190
        &answer);
191
    ipc_forward_fast(callid, mountee_phone, 0, 0, 0, IPC_FF_ROUTE_FROM_ME);
192
    async_wait_for(msg, &rc);
193
 
194
    if (rc == EOK) {
195
        fn->mp_data.mp_active = true;
196
        fn->mp_data.fs_handle = mr_fs_handle;
197
        fn->mp_data.dev_handle = mr_dev_handle;
198
        fn->mp_data.phone = mountee_phone;
199
    }
200
    /*
201
     * Do not release the FS node so that it stays in memory.
202
     */
4439 trochtova 203
    ipc_answer_3(rid, rc, IPC_GET_ARG1(answer), IPC_GET_ARG2(answer),
204
        IPC_GET_ARG3(answer));
4420 trochtova 205
}
206
 
2750 jermar 207
/** Lookup VFS triplet by name in the file system name space.
208
 *
2751 jermar 209
 * The path passed in the PLB must be in the canonical file system path format
210
 * as returned by the canonify() function.
211
 *
4537 trochtova 212
 * @param ops       libfs operations structure with function pointers to
213
 *                  file system implementation
214
 * @param fs_handle File system handle of the file system where to perform
215
 *                  the lookup.
216
 * @param rid       Request ID of the VFS_LOOKUP request.
217
 * @param request   VFS_LOOKUP request data itself.
218
 *
2750 jermar 219
 */
2770 jermar 220
void libfs_lookup(libfs_ops_t *ops, fs_handle_t fs_handle, ipc_callid_t rid,
2747 jermar 221
    ipc_call_t *request)
222
{
4420 trochtova 223
    unsigned first = IPC_GET_ARG1(*request);
2747 jermar 224
    unsigned last = IPC_GET_ARG2(*request);
4420 trochtova 225
    unsigned next = first;
2770 jermar 226
    dev_handle_t dev_handle = IPC_GET_ARG3(*request);
2747 jermar 227
    int lflag = IPC_GET_ARG4(*request);
2770 jermar 228
    fs_index_t index = IPC_GET_ARG5(*request); /* when L_LINK specified */
2847 jermar 229
    char component[NAME_MAX + 1];
230
    int len;
2747 jermar 231
 
232
    if (last < next)
233
        last += PLB_SIZE;
234
 
4420 trochtova 235
    fs_node_t *par = NULL;
236
    fs_node_t *cur = ops->root_get(dev_handle);
237
    fs_node_t *tmp = NULL;
2747 jermar 238
 
4420 trochtova 239
    if (cur->mp_data.mp_active) {
240
        ipc_forward_slow(rid, cur->mp_data.phone, VFS_LOOKUP,
241
            next, last, cur->mp_data.dev_handle, lflag, index,
242
            IPC_FF_ROUTE_FROM_ME);
243
        ops->node_put(cur);
244
        return;
245
    }
246
 
2747 jermar 247
    if (ops->plb_get_char(next) == '/')
248
        next++;     /* eat slash */
249
 
3002 jermar 250
    while (next <= last && ops->has_children(cur)) {
2747 jermar 251
        /* collect the component */
2847 jermar 252
        len = 0;
3003 jermar 253
        while ((next <= last) &&  (ops->plb_get_char(next) != '/')) {
2747 jermar 254
            if (len + 1 == NAME_MAX) {
4055 trochtova 255
                /* component length overflow */
2747 jermar 256
                ipc_answer_0(rid, ENAMETOOLONG);
2852 jermar 257
                goto out;
2747 jermar 258
            }
259
            component[len++] = ops->plb_get_char(next);
260
            next++; /* process next character */
261
        }
262
 
263
        assert(len);
264
        component[len] = '\0';
265
        next++;     /* eat slash */
266
 
267
        /* match the component */
2791 jermar 268
        tmp = ops->match(cur, component);
4420 trochtova 269
        if (tmp && tmp->mp_data.mp_active) {
270
            if (next > last)
271
                next = last = first;
272
            else
273
                next--;
274
 
275
            ipc_forward_slow(rid, tmp->mp_data.phone, VFS_LOOKUP,
276
                next, last, tmp->mp_data.dev_handle, lflag, index,
277
                IPC_FF_ROUTE_FROM_ME);
278
            ops->node_put(cur);
279
            ops->node_put(tmp);
280
            if (par)
281
                ops->node_put(par);
282
            return;
283
        }
2747 jermar 284
 
285
        /* handle miss: match amongst siblings */
286
        if (!tmp) {
2763 jermar 287
            if (next <= last) {
288
                /* there are unprocessed components */
289
                ipc_answer_0(rid, ENOENT);
2852 jermar 290
                goto out;
2763 jermar 291
            }
292
            /* miss in the last component */
293
            if (lflag & (L_CREATE | L_LINK)) {
294
                /* request to create a new link */
2747 jermar 295
                if (!ops->is_directory(cur)) {
296
                    ipc_answer_0(rid, ENOTDIR);
2852 jermar 297
                    goto out;
2763 jermar 298
                }
4420 trochtova 299
                fs_node_t *fn;
2763 jermar 300
                if (lflag & L_CREATE)
4420 trochtova 301
                    fn = ops->create(dev_handle, lflag);
2763 jermar 302
                else
4420 trochtova 303
                    fn = ops->node_get(dev_handle,
2863 jermar 304
                        index);
4420 trochtova 305
                if (fn) {
4055 trochtova 306
                    int rc;
307
 
4420 trochtova 308
                    rc = ops->link(cur, fn, component);
4055 trochtova 309
                    if (rc != EOK) {
3002 jermar 310
                        if (lflag & L_CREATE) {
4420 trochtova 311
                            (void)ops->destroy(fn);
3002 jermar 312
                        }
4055 trochtova 313
                        ipc_answer_0(rid, rc);
2747 jermar 314
                    } else {
315
                        ipc_answer_5(rid, EOK,
316
                            fs_handle, dev_handle,
4420 trochtova 317
                            ops->index_get(fn),
318
                            ops->size_get(fn),
319
                            ops->lnkcnt_get(fn));
320
                        ops->node_put(fn);
2747 jermar 321
                    }
322
                } else {
323
                    ipc_answer_0(rid, ENOSPC);
324
                }
2852 jermar 325
                goto out;
2763 jermar 326
            }
2747 jermar 327
            ipc_answer_0(rid, ENOENT);
2852 jermar 328
            goto out;
2747 jermar 329
        }
330
 
2852 jermar 331
        if (par)
332
            ops->node_put(par);
333
 
2747 jermar 334
        /* descend one level */
2758 jermar 335
        par = cur;
2747 jermar 336
        cur = tmp;
2852 jermar 337
        tmp = NULL;
2747 jermar 338
    }
339
 
340
    /* handle miss: excessive components */
3002 jermar 341
    if (next <= last && !ops->has_children(cur)) {
2763 jermar 342
        if (lflag & (L_CREATE | L_LINK)) {
2747 jermar 343
            if (!ops->is_directory(cur)) {
344
                ipc_answer_0(rid, ENOTDIR);
2852 jermar 345
                goto out;
2747 jermar 346
            }
347
 
348
            /* collect next component */
2847 jermar 349
            len = 0;
2747 jermar 350
            while (next <= last) {
351
                if (ops->plb_get_char(next) == '/') {
352
                    /* more than one component */
353
                    ipc_answer_0(rid, ENOENT);
2852 jermar 354
                    goto out;
2747 jermar 355
                }
356
                if (len + 1 == NAME_MAX) {
357
                    /* component length overflow */
358
                    ipc_answer_0(rid, ENAMETOOLONG);
2852 jermar 359
                    goto out;
2747 jermar 360
                }
361
                component[len++] = ops->plb_get_char(next);
362
                next++; /* process next character */
363
            }
364
            assert(len);
365
            component[len] = '\0';
366
 
4420 trochtova 367
            fs_node_t *fn;
2763 jermar 368
            if (lflag & L_CREATE)
4420 trochtova 369
                fn = ops->create(dev_handle, lflag);
2763 jermar 370
            else
4420 trochtova 371
                fn = ops->node_get(dev_handle, index);
372
            if (fn) {
4055 trochtova 373
                int rc;
374
 
4420 trochtova 375
                rc = ops->link(cur, fn, component);
4055 trochtova 376
                if (rc != EOK) {
2763 jermar 377
                    if (lflag & L_CREATE)
4420 trochtova 378
                        (void)ops->destroy(fn);
4055 trochtova 379
                    ipc_answer_0(rid, rc);
2747 jermar 380
                } else {
381
                    ipc_answer_5(rid, EOK,
382
                        fs_handle, dev_handle,
4420 trochtova 383
                        ops->index_get(fn),
384
                        ops->size_get(fn),
385
                        ops->lnkcnt_get(fn));
386
                    ops->node_put(fn);
2747 jermar 387
                }
388
            } else {
389
                ipc_answer_0(rid, ENOSPC);
390
            }
2852 jermar 391
            goto out;
2747 jermar 392
        }
393
        ipc_answer_0(rid, ENOENT);
2852 jermar 394
        goto out;
2747 jermar 395
    }
396
 
397
    /* handle hit */
2763 jermar 398
    if (lflag & L_UNLINK) {
2747 jermar 399
        unsigned old_lnkcnt = ops->lnkcnt_get(cur);
4420 trochtova 400
        int res = ops->unlink(par, cur, component);
2747 jermar 401
        ipc_answer_5(rid, (ipcarg_t)res, fs_handle, dev_handle,
402
            ops->index_get(cur), ops->size_get(cur), old_lnkcnt);
2852 jermar 403
        goto out;
2747 jermar 404
    }
2763 jermar 405
    if (((lflag & (L_CREATE | L_EXCLUSIVE)) == (L_CREATE | L_EXCLUSIVE)) ||
406
        (lflag & L_LINK)) {
2747 jermar 407
        ipc_answer_0(rid, EEXIST);
2852 jermar 408
        goto out;
2747 jermar 409
    }
410
    if ((lflag & L_FILE) && (ops->is_directory(cur))) {
411
        ipc_answer_0(rid, EISDIR);
2852 jermar 412
        goto out;
2747 jermar 413
    }
414
    if ((lflag & L_DIRECTORY) && (ops->is_file(cur))) {
415
        ipc_answer_0(rid, ENOTDIR);
2852 jermar 416
        goto out;
2747 jermar 417
    }
418
 
419
    ipc_answer_5(rid, EOK, fs_handle, dev_handle, ops->index_get(cur),
420
        ops->size_get(cur), ops->lnkcnt_get(cur));
2852 jermar 421
 
422
out:
423
    if (par)
424
        ops->node_put(par);
425
    if (cur)
426
        ops->node_put(cur);
427
    if (tmp)
428
        ops->node_put(tmp);
2747 jermar 429
}
430
 
4537 trochtova 431
/** Open VFS triplet.
432
 *
433
 * @param ops       libfs operations structure with function pointers to
434
 *                  file system implementation
435
 * @param rid       Request ID of the VFS_OPEN_NODE request.
436
 * @param request   VFS_OPEN_NODE request data itself.
437
 *
438
 */
439
void libfs_open_node(libfs_ops_t *ops, fs_handle_t fs_handle, ipc_callid_t rid,
440
    ipc_call_t *request)
441
{
442
    dev_handle_t dev_handle = IPC_GET_ARG1(*request);
443
    fs_index_t index = IPC_GET_ARG2(*request);
444
 
445
    fs_node_t *node = ops->node_get(dev_handle, index);
446
 
447
    if (node == NULL) {
448
        ipc_answer_0(rid, ENOENT);
449
        return;
450
    }
451
 
452
    ipc_answer_5(rid, EOK, fs_handle, dev_handle, index,
453
        ops->size_get(node), ops->lnkcnt_get(node));
454
 
455
    ops->node_put(node);
456
}
457
 
2642 jermar 458
/** @}
459
 */