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2642 jermar 1
/*
4409 jermar 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>
2642 jermar 45
 
2643 jermar 46
/** Register file system server.
47
 *
48
 * This function abstracts away the tedious registration protocol from
49
 * file system implementations and lets them to reuse this registration glue
50
 * code.
51
 *
52
 * @param vfs_phone Open phone for communication with VFS.
53
 * @param reg       File system registration structure. It will be
54
 *          initialized by this function.
55
 * @param info      VFS info structure supplied by the file system
56
 *          implementation.
57
 * @param conn      Connection fibril for handling all calls originating in
58
 *          VFS.
59
 *
60
 * @return      EOK on success or a non-zero error code on errror.
61
 */
62
int fs_register(int vfs_phone, fs_reg_t *reg, vfs_info_t *info,
63
    async_client_conn_t conn)
64
{
65
    /*
66
     * Tell VFS that we are here and want to get registered.
67
     * We use the async framework because VFS will answer the request
68
     * out-of-order, when it knows that the operation succeeded or failed.
69
     */
70
    ipc_call_t answer;
71
    aid_t req = async_send_0(vfs_phone, VFS_REGISTER, &answer);
72
 
73
    /*
74
     * Send our VFS info structure to VFS.
75
     */
2678 jermar 76
    int rc = ipc_data_write_start(vfs_phone, info, sizeof(*info));
2643 jermar 77
    if (rc != EOK) {
78
        async_wait_for(req, NULL);
79
        return rc;
80
    }
81
 
82
    /*
83
     * Ask VFS for callback connection.
84
     */
85
    ipc_connect_to_me(vfs_phone, 0, 0, 0, &reg->vfs_phonehash);
86
 
87
    /*
88
     * Allocate piece of address space for PLB.
89
     */
90
    reg->plb_ro = as_get_mappable_page(PLB_SIZE);
91
    if (!reg->plb_ro) {
92
        async_wait_for(req, NULL);
93
        return ENOMEM;
94
    }
95
 
96
    /*
97
     * Request sharing the Path Lookup Buffer with VFS.
98
     */
2678 jermar 99
    rc = ipc_share_in_start_0_0(vfs_phone, reg->plb_ro, PLB_SIZE);
2643 jermar 100
    if (rc) {
101
        async_wait_for(req, NULL);
102
        return rc;
103
    }
104
 
105
    /*
106
     * Pick up the answer for the request to the VFS_REQUEST call.
107
     */
108
    async_wait_for(req, NULL);
109
    reg->fs_handle = (int) IPC_GET_ARG1(answer);
110
 
111
    /*
112
     * Create a connection fibril to handle the callback connection.
113
     */
114
    async_new_connection(reg->vfs_phonehash, 0, NULL, conn);
115
 
116
    /*
117
     * Tell the async framework that other connections are to be handled by
118
     * the same connection fibril as well.
119
     */
120
    async_set_client_connection(conn);
121
 
122
    return IPC_GET_RETVAL(answer);
123
}
124
 
4409 jermar 125
void fs_node_initialize(fs_node_t *fn)
126
{
127
    memset(fn, 0, sizeof(fs_node_t));
128
}
129
 
130
void libfs_mount(libfs_ops_t *ops, ipc_callid_t rid, ipc_call_t *request)
131
{
4414 decky 132
    dev_handle_t mp_dev_handle = (dev_handle_t) IPC_GET_ARG1(*request);
133
    fs_index_t mp_fs_index = (fs_index_t) IPC_GET_ARG2(*request);
134
    fs_handle_t mr_fs_handle = (fs_handle_t) IPC_GET_ARG3(*request);
135
    dev_handle_t mr_dev_handle = (dev_handle_t) IPC_GET_ARG4(*request);
4409 jermar 136
    int res;
137
    ipcarg_t rc;
138
 
139
    ipc_call_t call;
140
    ipc_callid_t callid;
141
 
142
    /* accept the phone */
143
    callid = async_get_call(&call);
144
    int mountee_phone = (int)IPC_GET_ARG1(call);
145
    if ((IPC_GET_METHOD(call) != IPC_M_CONNECTION_CLONE) ||
146
        mountee_phone < 0) {
147
        ipc_answer_0(callid, EINVAL);
148
        ipc_answer_0(rid, EINVAL);
149
        return;
150
    }
151
    ipc_answer_0(callid, EOK);  /* acknowledge the mountee_phone */
152
 
153
    res = ipc_data_write_receive(&callid, NULL);
154
    if (!res) {
155
        ipc_hangup(mountee_phone);
156
        ipc_answer_0(callid, EINVAL);
157
        ipc_answer_0(rid, EINVAL);
158
        return;
159
    }
160
 
161
    fs_node_t *fn = ops->node_get(mp_dev_handle, mp_fs_index);
162
    if (!fn) {
163
        ipc_hangup(mountee_phone);
164
        ipc_answer_0(callid, ENOENT);
165
        ipc_answer_0(rid, ENOENT);
166
        return;
167
    }
168
 
169
    if (fn->mp_data.mp_active) {
170
        ipc_hangup(mountee_phone);
171
        ops->node_put(fn);
172
        ipc_answer_0(callid, EBUSY);
173
        ipc_answer_0(rid, EBUSY);
174
        return;
175
    }
176
 
177
    rc = async_req_0_0(mountee_phone, IPC_M_CONNECT_ME);
178
    if (rc != 0) {
179
        ipc_hangup(mountee_phone);
180
        ops->node_put(fn);
181
        ipc_answer_0(callid, rc);
182
        ipc_answer_0(rid, rc);
183
        return;
184
    }
185
 
186
    ipc_call_t answer;
187
    aid_t msg = async_send_1(mountee_phone, VFS_MOUNTED, mr_dev_handle,
188
        &answer);
189
    ipc_forward_fast(callid, mountee_phone, 0, 0, 0, IPC_FF_ROUTE_FROM_ME);
190
    async_wait_for(msg, &rc);
191
 
192
    if (rc == EOK) {
193
        fn->mp_data.mp_active = true;
194
        fn->mp_data.fs_handle = mr_fs_handle;
195
        fn->mp_data.dev_handle = mr_dev_handle;
196
        fn->mp_data.phone = mountee_phone;
197
    }
198
    /*
199
     * Do not release the FS node so that it stays in memory.
200
     */
201
    ipc_answer_0(rid, rc);
202
}
203
 
2750 jermar 204
/** Lookup VFS triplet by name in the file system name space.
205
 *
2751 jermar 206
 * The path passed in the PLB must be in the canonical file system path format
207
 * as returned by the canonify() function.
208
 *
2750 jermar 209
 * @param ops       libfs operations structure with function pointers to
210
 *          file system implementation
211
 * @param fs_handle File system handle of the file system where to perform
212
 *          the lookup.
213
 * @param rid       Request ID of the VFS_LOOKUP request.
214
 * @param request   VFS_LOOKUP request data itself.
215
 */
2770 jermar 216
void libfs_lookup(libfs_ops_t *ops, fs_handle_t fs_handle, ipc_callid_t rid,
2747 jermar 217
    ipc_call_t *request)
218
{
4409 jermar 219
    unsigned first = IPC_GET_ARG1(*request);
2747 jermar 220
    unsigned last = IPC_GET_ARG2(*request);
4409 jermar 221
    unsigned next = first;
2770 jermar 222
    dev_handle_t dev_handle = IPC_GET_ARG3(*request);
2747 jermar 223
    int lflag = IPC_GET_ARG4(*request);
2770 jermar 224
    fs_index_t index = IPC_GET_ARG5(*request); /* when L_LINK specified */
2847 jermar 225
    char component[NAME_MAX + 1];
226
    int len;
2747 jermar 227
 
228
    if (last < next)
229
        last += PLB_SIZE;
230
 
4357 jermar 231
    fs_node_t *par = NULL;
232
    fs_node_t *cur = ops->root_get(dev_handle);
233
    fs_node_t *tmp = NULL;
2747 jermar 234
 
4409 jermar 235
    if (cur->mp_data.mp_active) {
236
        ipc_forward_slow(rid, cur->mp_data.phone, VFS_LOOKUP,
237
            next, last, cur->mp_data.dev_handle, lflag, index,
238
            IPC_FF_ROUTE_FROM_ME);
239
        ops->node_put(cur);
240
        return;
241
    }
242
 
2747 jermar 243
    if (ops->plb_get_char(next) == '/')
244
        next++;     /* eat slash */
245
 
3002 jermar 246
    while (next <= last && ops->has_children(cur)) {
2747 jermar 247
        /* collect the component */
2847 jermar 248
        len = 0;
3003 jermar 249
        while ((next <= last) &&  (ops->plb_get_char(next) != '/')) {
2747 jermar 250
            if (len + 1 == NAME_MAX) {
3048 decky 251
                /* component length overflow */
2747 jermar 252
                ipc_answer_0(rid, ENAMETOOLONG);
2852 jermar 253
                goto out;
2747 jermar 254
            }
255
            component[len++] = ops->plb_get_char(next);
256
            next++; /* process next character */
257
        }
258
 
259
        assert(len);
260
        component[len] = '\0';
261
        next++;     /* eat slash */
262
 
263
        /* match the component */
2791 jermar 264
        tmp = ops->match(cur, component);
4409 jermar 265
        if (tmp && tmp->mp_data.mp_active) {
266
            if (next > last)
267
                next = last = first;
268
            else
269
                next--;
270
 
271
            ipc_forward_slow(rid, tmp->mp_data.phone, VFS_LOOKUP,
272
                next, last, tmp->mp_data.dev_handle, lflag, index,
273
                IPC_FF_ROUTE_FROM_ME);
274
            ops->node_put(cur);
275
            ops->node_put(tmp);
276
            if (par)
277
                ops->node_put(par);
278
            return;
279
        }
2747 jermar 280
 
281
        /* handle miss: match amongst siblings */
282
        if (!tmp) {
2763 jermar 283
            if (next <= last) {
284
                /* there are unprocessed components */
285
                ipc_answer_0(rid, ENOENT);
2852 jermar 286
                goto out;
2763 jermar 287
            }
288
            /* miss in the last component */
289
            if (lflag & (L_CREATE | L_LINK)) {
290
                /* request to create a new link */
2747 jermar 291
                if (!ops->is_directory(cur)) {
292
                    ipc_answer_0(rid, ENOTDIR);
2852 jermar 293
                    goto out;
2763 jermar 294
                }
4357 jermar 295
                fs_node_t *fn;
2763 jermar 296
                if (lflag & L_CREATE)
4357 jermar 297
                    fn = ops->create(dev_handle, lflag);
2763 jermar 298
                else
4357 jermar 299
                    fn = ops->node_get(dev_handle,
2863 jermar 300
                        index);
4357 jermar 301
                if (fn) {
3625 jermar 302
                    int rc;
303
 
4357 jermar 304
                    rc = ops->link(cur, fn, component);
3625 jermar 305
                    if (rc != EOK) {
3002 jermar 306
                        if (lflag & L_CREATE) {
4357 jermar 307
                            (void)ops->destroy(fn);
3002 jermar 308
                        }
3625 jermar 309
                        ipc_answer_0(rid, rc);
2747 jermar 310
                    } else {
311
                        ipc_answer_5(rid, EOK,
312
                            fs_handle, dev_handle,
4357 jermar 313
                            ops->index_get(fn),
314
                            ops->size_get(fn),
315
                            ops->lnkcnt_get(fn));
316
                        ops->node_put(fn);
2747 jermar 317
                    }
318
                } else {
319
                    ipc_answer_0(rid, ENOSPC);
320
                }
2852 jermar 321
                goto out;
2763 jermar 322
            }
2747 jermar 323
            ipc_answer_0(rid, ENOENT);
2852 jermar 324
            goto out;
2747 jermar 325
        }
326
 
2852 jermar 327
        if (par)
328
            ops->node_put(par);
329
 
2747 jermar 330
        /* descend one level */
2758 jermar 331
        par = cur;
2747 jermar 332
        cur = tmp;
2852 jermar 333
        tmp = NULL;
2747 jermar 334
    }
335
 
336
    /* handle miss: excessive components */
3002 jermar 337
    if (next <= last && !ops->has_children(cur)) {
2763 jermar 338
        if (lflag & (L_CREATE | L_LINK)) {
2747 jermar 339
            if (!ops->is_directory(cur)) {
340
                ipc_answer_0(rid, ENOTDIR);
2852 jermar 341
                goto out;
2747 jermar 342
            }
343
 
344
            /* collect next component */
2847 jermar 345
            len = 0;
2747 jermar 346
            while (next <= last) {
347
                if (ops->plb_get_char(next) == '/') {
348
                    /* more than one component */
349
                    ipc_answer_0(rid, ENOENT);
2852 jermar 350
                    goto out;
2747 jermar 351
                }
352
                if (len + 1 == NAME_MAX) {
353
                    /* component length overflow */
354
                    ipc_answer_0(rid, ENAMETOOLONG);
2852 jermar 355
                    goto out;
2747 jermar 356
                }
357
                component[len++] = ops->plb_get_char(next);
358
                next++; /* process next character */
359
            }
360
            assert(len);
361
            component[len] = '\0';
362
 
4357 jermar 363
            fs_node_t *fn;
2763 jermar 364
            if (lflag & L_CREATE)
4357 jermar 365
                fn = ops->create(dev_handle, lflag);
2763 jermar 366
            else
4357 jermar 367
                fn = ops->node_get(dev_handle, index);
368
            if (fn) {
3625 jermar 369
                int rc;
370
 
4357 jermar 371
                rc = ops->link(cur, fn, component);
3625 jermar 372
                if (rc != EOK) {
2763 jermar 373
                    if (lflag & L_CREATE)
4357 jermar 374
                        (void)ops->destroy(fn);
3625 jermar 375
                    ipc_answer_0(rid, rc);
2747 jermar 376
                } else {
377
                    ipc_answer_5(rid, EOK,
378
                        fs_handle, dev_handle,
4357 jermar 379
                        ops->index_get(fn),
380
                        ops->size_get(fn),
381
                        ops->lnkcnt_get(fn));
382
                    ops->node_put(fn);
2747 jermar 383
                }
384
            } else {
385
                ipc_answer_0(rid, ENOSPC);
386
            }
2852 jermar 387
            goto out;
2747 jermar 388
        }
389
        ipc_answer_0(rid, ENOENT);
2852 jermar 390
        goto out;
2747 jermar 391
    }
392
 
393
    /* handle hit */
2763 jermar 394
    if (lflag & L_UNLINK) {
2747 jermar 395
        unsigned old_lnkcnt = ops->lnkcnt_get(cur);
4370 jermar 396
        int res = ops->unlink(par, cur, component);
2747 jermar 397
        ipc_answer_5(rid, (ipcarg_t)res, fs_handle, dev_handle,
398
            ops->index_get(cur), ops->size_get(cur), old_lnkcnt);
2852 jermar 399
        goto out;
2747 jermar 400
    }
2763 jermar 401
    if (((lflag & (L_CREATE | L_EXCLUSIVE)) == (L_CREATE | L_EXCLUSIVE)) ||
402
        (lflag & L_LINK)) {
2747 jermar 403
        ipc_answer_0(rid, EEXIST);
2852 jermar 404
        goto out;
2747 jermar 405
    }
406
    if ((lflag & L_FILE) && (ops->is_directory(cur))) {
407
        ipc_answer_0(rid, EISDIR);
2852 jermar 408
        goto out;
2747 jermar 409
    }
410
    if ((lflag & L_DIRECTORY) && (ops->is_file(cur))) {
411
        ipc_answer_0(rid, ENOTDIR);
2852 jermar 412
        goto out;
2747 jermar 413
    }
414
 
415
    ipc_answer_5(rid, EOK, fs_handle, dev_handle, ops->index_get(cur),
416
        ops->size_get(cur), ops->lnkcnt_get(cur));
2852 jermar 417
 
418
out:
419
    if (par)
420
        ops->node_put(par);
421
    if (cur)
422
        ops->node_put(cur);
423
    if (tmp)
424
        ops->node_put(tmp);
2747 jermar 425
}
426
 
2642 jermar 427
/** @}
428
 */