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2642 jermar 1
/*
4692 svoboda 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>
4692 svoboda 45
#include <mem.h>
46
#include <sys/stat.h>
2642 jermar 47
 
2643 jermar 48
/** Register file system server.
49
 *
50
 * This function abstracts away the tedious registration protocol from
51
 * file system implementations and lets them to reuse this registration glue
52
 * code.
53
 *
54
 * @param vfs_phone Open phone for communication with VFS.
55
 * @param reg       File system registration structure. It will be
56
 *          initialized by this function.
57
 * @param info      VFS info structure supplied by the file system
58
 *          implementation.
59
 * @param conn      Connection fibril for handling all calls originating in
60
 *          VFS.
61
 *
62
 * @return      EOK on success or a non-zero error code on errror.
63
 */
64
int fs_register(int vfs_phone, fs_reg_t *reg, vfs_info_t *info,
65
    async_client_conn_t conn)
66
{
67
    /*
68
     * Tell VFS that we are here and want to get registered.
69
     * We use the async framework because VFS will answer the request
70
     * out-of-order, when it knows that the operation succeeded or failed.
71
     */
72
    ipc_call_t answer;
4692 svoboda 73
    aid_t req = async_send_0(vfs_phone, VFS_IN_REGISTER, &answer);
2643 jermar 74
 
75
    /*
76
     * Send our VFS info structure to VFS.
77
     */
2678 jermar 78
    int rc = ipc_data_write_start(vfs_phone, info, sizeof(*info));
2643 jermar 79
    if (rc != EOK) {
80
        async_wait_for(req, NULL);
81
        return rc;
82
    }
83
 
84
    /*
85
     * Ask VFS for callback connection.
86
     */
87
    ipc_connect_to_me(vfs_phone, 0, 0, 0, &reg->vfs_phonehash);
88
 
89
    /*
90
     * Allocate piece of address space for PLB.
91
     */
92
    reg->plb_ro = as_get_mappable_page(PLB_SIZE);
93
    if (!reg->plb_ro) {
94
        async_wait_for(req, NULL);
95
        return ENOMEM;
96
    }
97
 
98
    /*
99
     * Request sharing the Path Lookup Buffer with VFS.
100
     */
2678 jermar 101
    rc = ipc_share_in_start_0_0(vfs_phone, reg->plb_ro, PLB_SIZE);
2643 jermar 102
    if (rc) {
103
        async_wait_for(req, NULL);
104
        return rc;
105
    }
106
 
107
    /*
4692 svoboda 108
     * Pick up the answer for the request to the VFS_IN_REQUEST call.
2643 jermar 109
     */
110
    async_wait_for(req, NULL);
111
    reg->fs_handle = (int) IPC_GET_ARG1(answer);
112
 
113
    /*
114
     * Create a connection fibril to handle the callback connection.
115
     */
116
    async_new_connection(reg->vfs_phonehash, 0, NULL, conn);
117
 
118
    /*
119
     * Tell the async framework that other connections are to be handled by
120
     * the same connection fibril as well.
121
     */
122
    async_set_client_connection(conn);
123
 
124
    return IPC_GET_RETVAL(answer);
125
}
126
 
4692 svoboda 127
void fs_node_initialize(fs_node_t *fn)
128
{
129
    memset(fn, 0, sizeof(fs_node_t));
130
}
131
 
132
void libfs_mount(libfs_ops_t *ops, fs_handle_t fs_handle, ipc_callid_t rid,
133
    ipc_call_t *request)
134
{
135
    dev_handle_t mp_dev_handle = (dev_handle_t) IPC_GET_ARG1(*request);
136
    fs_index_t mp_fs_index = (fs_index_t) IPC_GET_ARG2(*request);
137
    fs_handle_t mr_fs_handle = (fs_handle_t) IPC_GET_ARG3(*request);
138
    dev_handle_t mr_dev_handle = (dev_handle_t) IPC_GET_ARG4(*request);
139
    int res;
140
    ipcarg_t rc;
141
 
142
    ipc_call_t call;
143
    ipc_callid_t callid;
144
 
145
    /* accept the phone */
146
    callid = async_get_call(&call);
147
    int mountee_phone = (int)IPC_GET_ARG1(call);
148
    if ((IPC_GET_METHOD(call) != IPC_M_CONNECTION_CLONE) ||
149
        mountee_phone < 0) {
150
        ipc_answer_0(callid, EINVAL);
151
        ipc_answer_0(rid, EINVAL);
152
        return;
153
    }
154
    ipc_answer_0(callid, EOK);  /* acknowledge the mountee_phone */
155
 
156
    res = ipc_data_write_receive(&callid, NULL);
157
    if (!res) {
158
        ipc_hangup(mountee_phone);
159
        ipc_answer_0(callid, EINVAL);
160
        ipc_answer_0(rid, EINVAL);
161
        return;
162
    }
163
 
164
    fs_node_t *fn = ops->node_get(mp_dev_handle, mp_fs_index);
165
    if (!fn) {
166
        ipc_hangup(mountee_phone);
167
        ipc_answer_0(callid, ENOENT);
168
        ipc_answer_0(rid, ENOENT);
169
        return;
170
    }
171
 
172
    if (fn->mp_data.mp_active) {
173
        ipc_hangup(mountee_phone);
174
        ops->node_put(fn);
175
        ipc_answer_0(callid, EBUSY);
176
        ipc_answer_0(rid, EBUSY);
177
        return;
178
    }
179
 
180
    rc = async_req_0_0(mountee_phone, IPC_M_CONNECT_ME);
181
    if (rc != 0) {
182
        ipc_hangup(mountee_phone);
183
        ops->node_put(fn);
184
        ipc_answer_0(callid, rc);
185
        ipc_answer_0(rid, rc);
186
        return;
187
    }
188
 
189
    ipc_call_t answer;
190
    aid_t msg = async_send_1(mountee_phone, VFS_OUT_MOUNTED, mr_dev_handle,
191
        &answer);
192
    ipc_forward_fast(callid, mountee_phone, 0, 0, 0, IPC_FF_ROUTE_FROM_ME);
193
    async_wait_for(msg, &rc);
194
 
195
    if (rc == EOK) {
196
        fn->mp_data.mp_active = true;
197
        fn->mp_data.fs_handle = mr_fs_handle;
198
        fn->mp_data.dev_handle = mr_dev_handle;
199
        fn->mp_data.phone = mountee_phone;
200
    }
201
    /*
202
     * Do not release the FS node so that it stays in memory.
203
     */
204
    ipc_answer_3(rid, rc, IPC_GET_ARG1(answer), IPC_GET_ARG2(answer),
205
        IPC_GET_ARG3(answer));
206
}
207
 
2750 jermar 208
/** Lookup VFS triplet by name in the file system name space.
209
 *
2751 jermar 210
 * The path passed in the PLB must be in the canonical file system path format
211
 * as returned by the canonify() function.
212
 *
4692 svoboda 213
 * @param ops       libfs operations structure with function pointers to
214
 *                  file system implementation
215
 * @param fs_handle File system handle of the file system where to perform
216
 *                  the lookup.
217
 * @param rid       Request ID of the VFS_OUT_LOOKUP request.
218
 * @param request   VFS_OUT_LOOKUP request data itself.
219
 *
2750 jermar 220
 */
2770 jermar 221
void libfs_lookup(libfs_ops_t *ops, fs_handle_t fs_handle, ipc_callid_t rid,
2747 jermar 222
    ipc_call_t *request)
223
{
4692 svoboda 224
    unsigned first = IPC_GET_ARG1(*request);
2747 jermar 225
    unsigned last = IPC_GET_ARG2(*request);
4692 svoboda 226
    unsigned next = first;
2770 jermar 227
    dev_handle_t dev_handle = IPC_GET_ARG3(*request);
2747 jermar 228
    int lflag = IPC_GET_ARG4(*request);
2770 jermar 229
    fs_index_t index = IPC_GET_ARG5(*request); /* when L_LINK specified */
2925 svoboda 230
    char component[NAME_MAX + 1];
231
    int len;
2747 jermar 232
 
233
    if (last < next)
234
        last += PLB_SIZE;
235
 
4377 svoboda 236
    fs_node_t *par = NULL;
237
    fs_node_t *cur = ops->root_get(dev_handle);
238
    fs_node_t *tmp = NULL;
2747 jermar 239
 
4692 svoboda 240
    if (cur->mp_data.mp_active) {
241
        ipc_forward_slow(rid, cur->mp_data.phone, VFS_OUT_LOOKUP,
242
            next, last, cur->mp_data.dev_handle, lflag, index,
243
            IPC_FF_ROUTE_FROM_ME);
244
        ops->node_put(cur);
245
        return;
246
    }
247
 
2747 jermar 248
    if (ops->plb_get_char(next) == '/')
249
        next++;     /* eat slash */
250
 
3011 svoboda 251
    while (next <= last && ops->has_children(cur)) {
2747 jermar 252
        /* collect the component */
2925 svoboda 253
        len = 0;
3011 svoboda 254
        while ((next <= last) &&  (ops->plb_get_char(next) != '/')) {
2747 jermar 255
            if (len + 1 == NAME_MAX) {
3424 svoboda 256
                /* component length overflow */
2747 jermar 257
                ipc_answer_0(rid, ENAMETOOLONG);
2925 svoboda 258
                goto out;
2747 jermar 259
            }
260
            component[len++] = ops->plb_get_char(next);
261
            next++; /* process next character */
262
        }
263
 
264
        assert(len);
265
        component[len] = '\0';
266
        next++;     /* eat slash */
267
 
268
        /* match the component */
2925 svoboda 269
        tmp = ops->match(cur, component);
4692 svoboda 270
        if (tmp && tmp->mp_data.mp_active) {
271
            if (next > last)
272
                next = last = first;
273
            else
274
                next--;
275
 
276
            ipc_forward_slow(rid, tmp->mp_data.phone,
277
                VFS_OUT_LOOKUP, next, last, tmp->mp_data.dev_handle,
278
                lflag, index, IPC_FF_ROUTE_FROM_ME);
279
            ops->node_put(cur);
280
            ops->node_put(tmp);
281
            if (par)
282
                ops->node_put(par);
283
            return;
284
        }
2747 jermar 285
 
286
        /* handle miss: match amongst siblings */
287
        if (!tmp) {
2763 jermar 288
            if (next <= last) {
289
                /* there are unprocessed components */
290
                ipc_answer_0(rid, ENOENT);
2925 svoboda 291
                goto out;
2763 jermar 292
            }
293
            /* miss in the last component */
294
            if (lflag & (L_CREATE | L_LINK)) {
295
                /* request to create a new link */
2747 jermar 296
                if (!ops->is_directory(cur)) {
297
                    ipc_answer_0(rid, ENOTDIR);
2925 svoboda 298
                    goto out;
2763 jermar 299
                }
4377 svoboda 300
                fs_node_t *fn;
2763 jermar 301
                if (lflag & L_CREATE)
4377 svoboda 302
                    fn = ops->create(dev_handle, lflag);
2763 jermar 303
                else
4377 svoboda 304
                    fn = ops->node_get(dev_handle,
2925 svoboda 305
                        index);
4377 svoboda 306
                if (fn) {
3675 svoboda 307
                    int rc;
308
 
4377 svoboda 309
                    rc = ops->link(cur, fn, component);
3675 svoboda 310
                    if (rc != EOK) {
3011 svoboda 311
                        if (lflag & L_CREATE) {
4377 svoboda 312
                            (void)ops->destroy(fn);
3011 svoboda 313
                        }
3675 svoboda 314
                        ipc_answer_0(rid, rc);
2747 jermar 315
                    } else {
316
                        ipc_answer_5(rid, EOK,
317
                            fs_handle, dev_handle,
4377 svoboda 318
                            ops->index_get(fn),
319
                            ops->size_get(fn),
320
                            ops->lnkcnt_get(fn));
321
                        ops->node_put(fn);
2747 jermar 322
                    }
323
                } else {
324
                    ipc_answer_0(rid, ENOSPC);
325
                }
2925 svoboda 326
                goto out;
2763 jermar 327
            }
2747 jermar 328
            ipc_answer_0(rid, ENOENT);
2925 svoboda 329
            goto out;
2747 jermar 330
        }
331
 
2925 svoboda 332
        if (par)
333
            ops->node_put(par);
334
 
2747 jermar 335
        /* descend one level */
2758 jermar 336
        par = cur;
2747 jermar 337
        cur = tmp;
2925 svoboda 338
        tmp = NULL;
2747 jermar 339
    }
340
 
341
    /* handle miss: excessive components */
3011 svoboda 342
    if (next <= last && !ops->has_children(cur)) {
2763 jermar 343
        if (lflag & (L_CREATE | L_LINK)) {
2747 jermar 344
            if (!ops->is_directory(cur)) {
345
                ipc_answer_0(rid, ENOTDIR);
2925 svoboda 346
                goto out;
2747 jermar 347
            }
348
 
349
            /* collect next component */
2925 svoboda 350
            len = 0;
2747 jermar 351
            while (next <= last) {
352
                if (ops->plb_get_char(next) == '/') {
353
                    /* more than one component */
354
                    ipc_answer_0(rid, ENOENT);
2925 svoboda 355
                    goto out;
2747 jermar 356
                }
357
                if (len + 1 == NAME_MAX) {
358
                    /* component length overflow */
359
                    ipc_answer_0(rid, ENAMETOOLONG);
2925 svoboda 360
                    goto out;
2747 jermar 361
                }
362
                component[len++] = ops->plb_get_char(next);
363
                next++; /* process next character */
364
            }
365
            assert(len);
366
            component[len] = '\0';
367
 
4377 svoboda 368
            fs_node_t *fn;
2763 jermar 369
            if (lflag & L_CREATE)
4377 svoboda 370
                fn = ops->create(dev_handle, lflag);
2763 jermar 371
            else
4377 svoboda 372
                fn = ops->node_get(dev_handle, index);
373
            if (fn) {
3675 svoboda 374
                int rc;
375
 
4377 svoboda 376
                rc = ops->link(cur, fn, component);
3675 svoboda 377
                if (rc != EOK) {
2763 jermar 378
                    if (lflag & L_CREATE)
4377 svoboda 379
                        (void)ops->destroy(fn);
3675 svoboda 380
                    ipc_answer_0(rid, rc);
2747 jermar 381
                } else {
382
                    ipc_answer_5(rid, EOK,
383
                        fs_handle, dev_handle,
4377 svoboda 384
                        ops->index_get(fn),
385
                        ops->size_get(fn),
386
                        ops->lnkcnt_get(fn));
387
                    ops->node_put(fn);
2747 jermar 388
                }
389
            } else {
390
                ipc_answer_0(rid, ENOSPC);
391
            }
2925 svoboda 392
            goto out;
2747 jermar 393
        }
394
        ipc_answer_0(rid, ENOENT);
2925 svoboda 395
        goto out;
2747 jermar 396
    }
397
 
398
    /* handle hit */
2763 jermar 399
    if (lflag & L_UNLINK) {
2747 jermar 400
        unsigned old_lnkcnt = ops->lnkcnt_get(cur);
4377 svoboda 401
        int res = ops->unlink(par, cur, component);
2747 jermar 402
        ipc_answer_5(rid, (ipcarg_t)res, fs_handle, dev_handle,
403
            ops->index_get(cur), ops->size_get(cur), old_lnkcnt);
2925 svoboda 404
        goto out;
2747 jermar 405
    }
2763 jermar 406
    if (((lflag & (L_CREATE | L_EXCLUSIVE)) == (L_CREATE | L_EXCLUSIVE)) ||
407
        (lflag & L_LINK)) {
2747 jermar 408
        ipc_answer_0(rid, EEXIST);
2925 svoboda 409
        goto out;
2747 jermar 410
    }
411
    if ((lflag & L_FILE) && (ops->is_directory(cur))) {
412
        ipc_answer_0(rid, EISDIR);
2925 svoboda 413
        goto out;
2747 jermar 414
    }
415
    if ((lflag & L_DIRECTORY) && (ops->is_file(cur))) {
416
        ipc_answer_0(rid, ENOTDIR);
2925 svoboda 417
        goto out;
2747 jermar 418
    }
419
 
420
    ipc_answer_5(rid, EOK, fs_handle, dev_handle, ops->index_get(cur),
421
        ops->size_get(cur), ops->lnkcnt_get(cur));
2925 svoboda 422
 
423
out:
424
    if (par)
425
        ops->node_put(par);
426
    if (cur)
427
        ops->node_put(cur);
428
    if (tmp)
429
        ops->node_put(tmp);
2747 jermar 430
}
431
 
4692 svoboda 432
void libfs_stat(libfs_ops_t *ops, fs_handle_t fs_handle, ipc_callid_t rid,
433
    ipc_call_t *request)
434
{
435
    dev_handle_t dev_handle = (dev_handle_t) IPC_GET_ARG1(*request);
436
    fs_index_t index = (fs_index_t) IPC_GET_ARG2(*request);
437
    fs_node_t *fn = ops->node_get(dev_handle, index);
438
 
439
    ipc_callid_t callid;
440
    size_t size;
441
    if (!ipc_data_read_receive(&callid, &size) ||
442
        size != sizeof(struct stat)) {
443
        ipc_answer_0(callid, EINVAL);
444
        ipc_answer_0(rid, EINVAL);
445
        return;
446
    }
447
 
448
    struct stat stat;
449
    memset(&stat, 0, sizeof(struct stat));
450
 
451
    stat.fs_handle = fs_handle;
452
    stat.dev_handle = dev_handle;
453
    stat.index = index;
454
    stat.lnkcnt = ops->lnkcnt_get(fn);
455
    stat.is_file = ops->is_file(fn);
456
    stat.size = ops->size_get(fn);
457
 
458
    ipc_data_read_finalize(callid, &stat, sizeof(struct stat));
459
    ipc_answer_0(rid, EOK);
460
}
461
 
462
/** Open VFS triplet.
463
 *
464
 * @param ops       libfs operations structure with function pointers to
465
 *                  file system implementation
466
 * @param rid       Request ID of the VFS_OUT_OPEN_NODE request.
467
 * @param request   VFS_OUT_OPEN_NODE request data itself.
468
 *
469
 */
470
void libfs_open_node(libfs_ops_t *ops, fs_handle_t fs_handle, ipc_callid_t rid,
471
    ipc_call_t *request)
472
{
473
    dev_handle_t dev_handle = IPC_GET_ARG1(*request);
474
    fs_index_t index = IPC_GET_ARG2(*request);
475
 
476
    fs_node_t *node = ops->node_get(dev_handle, index);
477
 
478
    if (node == NULL) {
479
        ipc_answer_0(rid, ENOENT);
480
        return;
481
    }
482
 
483
    ipc_answer_5(rid, EOK, fs_handle, dev_handle, index,
484
        ops->size_get(node), ops->lnkcnt_get(node));
485
 
486
    ops->node_put(node);
487
}
488
 
2642 jermar 489
/** @}
490
 */