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2642 jermar 1
/*
2747 jermar 2
 * Copyright (c) 2008 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"
3254 jermar 39
#include "../../srv/rd/rd.h"
2643 jermar 40
#include <errno.h>
41
#include <async.h>
42
#include <ipc/ipc.h>
43
#include <as.h>
2747 jermar 44
#include <assert.h>
45
#include <dirent.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
 
2750 jermar 126
/** Lookup VFS triplet by name in the file system name space.
127
 *
2751 jermar 128
 * The path passed in the PLB must be in the canonical file system path format
129
 * as returned by the canonify() function.
130
 *
2750 jermar 131
 * @param ops       libfs operations structure with function pointers to
132
 *          file system implementation
133
 * @param fs_handle File system handle of the file system where to perform
134
 *          the lookup.
135
 * @param rid       Request ID of the VFS_LOOKUP request.
136
 * @param request   VFS_LOOKUP request data itself.
137
 */
2770 jermar 138
void libfs_lookup(libfs_ops_t *ops, fs_handle_t fs_handle, ipc_callid_t rid,
2747 jermar 139
    ipc_call_t *request)
140
{
141
    unsigned next = IPC_GET_ARG1(*request);
142
    unsigned last = IPC_GET_ARG2(*request);
2770 jermar 143
    dev_handle_t dev_handle = IPC_GET_ARG3(*request);
2747 jermar 144
    int lflag = IPC_GET_ARG4(*request);
2770 jermar 145
    fs_index_t index = IPC_GET_ARG5(*request); /* when L_LINK specified */
2847 jermar 146
    char component[NAME_MAX + 1];
147
    int len;
2747 jermar 148
 
149
    if (last < next)
150
        last += PLB_SIZE;
151
 
2758 jermar 152
    void *par = NULL;
2844 jermar 153
    void *cur = ops->root_get(dev_handle);
2852 jermar 154
    void *tmp = NULL;
2747 jermar 155
 
156
    if (ops->plb_get_char(next) == '/')
157
        next++;     /* eat slash */
158
 
3002 jermar 159
    while (next <= last && ops->has_children(cur)) {
2747 jermar 160
        /* collect the component */
2847 jermar 161
        len = 0;
3003 jermar 162
        while ((next <= last) &&  (ops->plb_get_char(next) != '/')) {
2747 jermar 163
            if (len + 1 == NAME_MAX) {
3048 decky 164
                /* component length overflow */
2747 jermar 165
                ipc_answer_0(rid, ENAMETOOLONG);
2852 jermar 166
                goto out;
2747 jermar 167
            }
168
            component[len++] = ops->plb_get_char(next);
169
            next++; /* process next character */
170
        }
171
 
172
        assert(len);
173
        component[len] = '\0';
174
        next++;     /* eat slash */
175
 
176
        /* match the component */
2791 jermar 177
        tmp = ops->match(cur, component);
2747 jermar 178
 
179
        /* handle miss: match amongst siblings */
180
        if (!tmp) {
2763 jermar 181
            if (next <= last) {
182
                /* there are unprocessed components */
183
                ipc_answer_0(rid, ENOENT);
2852 jermar 184
                goto out;
2763 jermar 185
            }
186
            /* miss in the last component */
187
            if (lflag & (L_CREATE | L_LINK)) {
188
                /* request to create a new link */
2747 jermar 189
                if (!ops->is_directory(cur)) {
190
                    ipc_answer_0(rid, ENOTDIR);
2852 jermar 191
                    goto out;
2763 jermar 192
                }
193
                void *nodep;
194
                if (lflag & L_CREATE)
195
                    nodep = ops->create(lflag);
196
                else
2792 jermar 197
                    nodep = ops->node_get(dev_handle,
2863 jermar 198
                        index);
2747 jermar 199
                if (nodep) {
200
                    if (!ops->link(cur, nodep, component)) {
3002 jermar 201
                        if (lflag & L_CREATE) {
202
                            (void)ops->destroy(
203
                                nodep);
204
                        }
2747 jermar 205
                        ipc_answer_0(rid, ENOSPC);
206
                    } else {
207
                        ipc_answer_5(rid, EOK,
208
                            fs_handle, dev_handle,
2763 jermar 209
                            ops->index_get(nodep),
210
                            ops->size_get(nodep),
2747 jermar 211
                            ops->lnkcnt_get(nodep));
2852 jermar 212
                        ops->node_put(nodep);
2747 jermar 213
                    }
214
                } else {
215
                    ipc_answer_0(rid, ENOSPC);
216
                }
2852 jermar 217
                goto out;
2763 jermar 218
            } else if (lflag & L_PARENT) {
219
                /* return parent */
220
                ipc_answer_5(rid, EOK, fs_handle, dev_handle,
221
                    ops->index_get(cur), ops->size_get(cur),
222
                    ops->lnkcnt_get(cur));
223
            }
2747 jermar 224
            ipc_answer_0(rid, ENOENT);
2852 jermar 225
            goto out;
2747 jermar 226
        }
227
 
2852 jermar 228
        if (par)
229
            ops->node_put(par);
230
 
2747 jermar 231
        /* descend one level */
2758 jermar 232
        par = cur;
2747 jermar 233
        cur = tmp;
2852 jermar 234
        tmp = NULL;
2747 jermar 235
    }
236
 
237
    /* handle miss: excessive components */
3002 jermar 238
    if (next <= last && !ops->has_children(cur)) {
2763 jermar 239
        if (lflag & (L_CREATE | L_LINK)) {
2747 jermar 240
            if (!ops->is_directory(cur)) {
241
                ipc_answer_0(rid, ENOTDIR);
2852 jermar 242
                goto out;
2747 jermar 243
            }
244
 
245
            /* collect next component */
2847 jermar 246
            len = 0;
2747 jermar 247
            while (next <= last) {
248
                if (ops->plb_get_char(next) == '/') {
249
                    /* more than one component */
250
                    ipc_answer_0(rid, ENOENT);
2852 jermar 251
                    goto out;
2747 jermar 252
                }
253
                if (len + 1 == NAME_MAX) {
254
                    /* component length overflow */
255
                    ipc_answer_0(rid, ENAMETOOLONG);
2852 jermar 256
                    goto out;
2747 jermar 257
                }
258
                component[len++] = ops->plb_get_char(next);
259
                next++; /* process next character */
260
            }
261
            assert(len);
262
            component[len] = '\0';
263
 
2763 jermar 264
            void *nodep;
265
            if (lflag & L_CREATE)
266
                nodep = ops->create(lflag);
267
            else
2863 jermar 268
                nodep = ops->node_get(dev_handle, index);
2747 jermar 269
            if (nodep) {
270
                if (!ops->link(cur, nodep, component)) {
2763 jermar 271
                    if (lflag & L_CREATE)
2857 jermar 272
                        (void)ops->destroy(nodep);
2747 jermar 273
                    ipc_answer_0(rid, ENOSPC);
274
                } else {
275
                    ipc_answer_5(rid, EOK,
276
                        fs_handle, dev_handle,
2763 jermar 277
                        ops->index_get(nodep),
278
                        ops->size_get(nodep),
2747 jermar 279
                        ops->lnkcnt_get(nodep));
2852 jermar 280
                    ops->node_put(nodep);
2747 jermar 281
                }
282
            } else {
283
                ipc_answer_0(rid, ENOSPC);
284
            }
2852 jermar 285
            goto out;
2747 jermar 286
        }
287
        ipc_answer_0(rid, ENOENT);
2852 jermar 288
        goto out;
2747 jermar 289
    }
290
 
291
    /* handle hit */
2763 jermar 292
    if (lflag & L_PARENT) {
2852 jermar 293
        ops->node_put(cur);
2763 jermar 294
        cur = par;
2852 jermar 295
        par = NULL;
2763 jermar 296
        if (!cur) {
297
            ipc_answer_0(rid, ENOENT);
2852 jermar 298
            goto out;
2763 jermar 299
        }
300
    }
301
    if (lflag & L_UNLINK) {
2747 jermar 302
        unsigned old_lnkcnt = ops->lnkcnt_get(cur);
2758 jermar 303
        int res = ops->unlink(par, cur);
2747 jermar 304
        ipc_answer_5(rid, (ipcarg_t)res, fs_handle, dev_handle,
305
            ops->index_get(cur), ops->size_get(cur), old_lnkcnt);
2852 jermar 306
        goto out;
2747 jermar 307
    }
2763 jermar 308
    if (((lflag & (L_CREATE | L_EXCLUSIVE)) == (L_CREATE | L_EXCLUSIVE)) ||
309
        (lflag & L_LINK)) {
2747 jermar 310
        ipc_answer_0(rid, EEXIST);
2852 jermar 311
        goto out;
2747 jermar 312
    }
313
    if ((lflag & L_FILE) && (ops->is_directory(cur))) {
314
        ipc_answer_0(rid, EISDIR);
2852 jermar 315
        goto out;
2747 jermar 316
    }
317
    if ((lflag & L_DIRECTORY) && (ops->is_file(cur))) {
318
        ipc_answer_0(rid, ENOTDIR);
2852 jermar 319
        goto out;
2747 jermar 320
    }
321
 
322
    ipc_answer_5(rid, EOK, fs_handle, dev_handle, ops->index_get(cur),
323
        ops->size_get(cur), ops->lnkcnt_get(cur));
2852 jermar 324
 
325
out:
326
    if (par)
327
        ops->node_put(par);
328
    if (cur)
329
        ops->node_put(cur);
330
    if (tmp)
331
        ops->node_put(tmp);
2747 jermar 332
}
333
 
3252 jermar 334
/** Read data from a block device.
335
 *
336
 * @param phone     Phone to be used to communicate with the device.
337
 * @param buffer    Communication buffer shared with the device.
338
 * @param bufpos    Pointer to the first unread valid offset within the
339
 *          communication buffer.
340
 * @param buflen    Pointer to the number of unread bytes that are ready in
341
 *          the communication buffer.
342
 * @param pos       Device position to be read.
343
 * @param dst       Destination buffer.
344
 * @param size      Size of the destination buffer.
345
 * @param block_size    Block size to be used for the transfer.
346
 *
347
 * @return      True on success, false on failure.
348
 */
349
bool libfs_blockread(int phone, void *buffer, off_t *bufpos, size_t *buflen,
350
    off_t *pos, void *dst, size_t size, size_t block_size)
3251 jermar 351
{
3252 jermar 352
    off_t offset = 0;
3251 jermar 353
    size_t left = size;
354
 
355
    while (left > 0) {
356
        size_t rd;
357
 
358
        if (*bufpos + left < *buflen)
359
            rd = left;
360
        else
361
            rd = *buflen - *bufpos;
362
 
363
        if (rd > 0) {
3252 jermar 364
            /*
365
             * Copy the contents of the communication buffer to the
366
             * destination buffer.
367
             */
3251 jermar 368
            memcpy(dst + offset, buffer + *bufpos, rd);
369
            offset += rd;
370
            *bufpos += rd;
371
            *pos += rd;
372
            left -= rd;
373
        }
374
 
375
        if (*bufpos == *buflen) {
3252 jermar 376
            /* Refill the communication buffer with a new block. */
3251 jermar 377
            ipcarg_t retval;
378
            int rc = async_req_2_1(phone, RD_READ_BLOCK,
379
                *pos / block_size, block_size, &retval);
380
            if ((rc != EOK) || (retval != EOK))
381
                return false;
382
 
383
            *bufpos = 0;
384
            *buflen = block_size;
385
        }
386
    }
387
 
388
    return true;
389
}
390
 
2642 jermar 391
/** @}
392
 */