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Line 43... Line 43...
43
#include <stdio.h>
43
#include <stdio.h>
44
#include <stdlib.h>
44
#include <stdlib.h>
45
#include <string.h>
45
#include <string.h>
46
#include <ctype.h>
46
#include <ctype.h>
47
#include <bool.h>
47
#include <bool.h>
48
#include <futex.h>
48
#include <fibril_sync.h>
49
#include <libadt/list.h>
49
#include <adt/list.h>
50
#include <as.h>
50
#include <as.h>
51
#include <assert.h>
51
#include <assert.h>
52
#include <atomic.h>
52
#include <atomic.h>
53
#include "vfs.h"
53
#include "vfs.h"
54
 
54
 
55
atomic_t fs_head_futex = FUTEX_INITIALIZER;
55
FIBRIL_MUTEX_INITIALIZE(fs_head_lock);
56
link_t fs_head;
56
link_t fs_head;
57
 
57
 
58
atomic_t fs_handle_next = {
58
atomic_t fs_handle_next = {
59
    .count = 1
59
    .count = 1
60
};
60
};
Line 157... Line 157...
157
        ipc_answer_0(callid, ENOMEM);
157
        ipc_answer_0(callid, ENOMEM);
158
        ipc_answer_0(rid, ENOMEM);
158
        ipc_answer_0(rid, ENOMEM);
159
        return;
159
        return;
160
    }
160
    }
161
    link_initialize(&fs_info->fs_link);
161
    link_initialize(&fs_info->fs_link);
162
    futex_initialize(&fs_info->phone_futex, 1);
162
    fibril_mutex_initialize(&fs_info->phone_lock);
163
       
163
       
164
    rc = ipc_data_write_finalize(callid, &fs_info->vfs_info, size);
164
    rc = ipc_data_write_finalize(callid, &fs_info->vfs_info, size);
165
    if (rc != EOK) {
165
    if (rc != EOK) {
166
        dprintf("Failed to deliver the VFS info into our AS, rc=%d.\n",
166
        dprintf("Failed to deliver the VFS info into our AS, rc=%d.\n",
167
            rc);
167
            rc);
Line 178... Line 178...
178
        ipc_answer_0(callid, EINVAL);
178
        ipc_answer_0(callid, EINVAL);
179
        ipc_answer_0(rid, EINVAL);
179
        ipc_answer_0(rid, EINVAL);
180
        return;
180
        return;
181
    }
181
    }
182
       
182
       
183
    futex_down(&fs_head_futex);
183
    fibril_mutex_lock(&fs_head_lock);
184
    fibril_inc_sercount();
-
 
185
 
184
 
186
    /*
185
    /*
187
     * Check for duplicit registrations.
186
     * Check for duplicit registrations.
188
     */
187
     */
189
    if (fs_name_to_handle(fs_info->vfs_info.name, false)) {
188
    if (fs_name_to_handle(fs_info->vfs_info.name, false)) {
190
        /*
189
        /*
191
         * We already register a fs like this.
190
         * We already register a fs like this.
192
         */
191
         */
193
        dprintf("FS is already registered.\n");
192
        dprintf("FS is already registered.\n");
194
        fibril_dec_sercount();
-
 
195
        futex_up(&fs_head_futex);
193
        fibril_mutex_unlock(&fs_head_lock);
196
        free(fs_info);
194
        free(fs_info);
197
        ipc_answer_0(callid, EEXISTS);
195
        ipc_answer_0(callid, EEXISTS);
198
        ipc_answer_0(rid, EEXISTS);
196
        ipc_answer_0(rid, EEXISTS);
199
        return;
197
        return;
200
    }
198
    }
Line 212... Line 210...
212
     */
210
     */
213
    callid = async_get_call(&call);
211
    callid = async_get_call(&call);
214
    if (IPC_GET_METHOD(call) != IPC_M_CONNECT_TO_ME) {
212
    if (IPC_GET_METHOD(call) != IPC_M_CONNECT_TO_ME) {
215
        dprintf("Unexpected call, method = %d\n", IPC_GET_METHOD(call));
213
        dprintf("Unexpected call, method = %d\n", IPC_GET_METHOD(call));
216
        list_remove(&fs_info->fs_link);
214
        list_remove(&fs_info->fs_link);
217
        fibril_dec_sercount();
-
 
218
        futex_up(&fs_head_futex);
215
        fibril_mutex_unlock(&fs_head_lock);
219
        free(fs_info);
216
        free(fs_info);
220
        ipc_answer_0(callid, EINVAL);
217
        ipc_answer_0(callid, EINVAL);
221
        ipc_answer_0(rid, EINVAL);
218
        ipc_answer_0(rid, EINVAL);
222
        return;
219
        return;
223
    }
220
    }
Line 231... Line 228...
231
     */
228
     */
232
 
229
 
233
    if (!ipc_share_in_receive(&callid, &size)) {
230
    if (!ipc_share_in_receive(&callid, &size)) {
234
        dprintf("Unexpected call, method = %d\n", IPC_GET_METHOD(call));
231
        dprintf("Unexpected call, method = %d\n", IPC_GET_METHOD(call));
235
        list_remove(&fs_info->fs_link);
232
        list_remove(&fs_info->fs_link);
236
        fibril_dec_sercount();
-
 
237
        futex_up(&fs_head_futex);
233
        fibril_mutex_unlock(&fs_head_lock);
238
        ipc_hangup(fs_info->phone);
234
        ipc_hangup(fs_info->phone);
239
        free(fs_info);
235
        free(fs_info);
240
        ipc_answer_0(callid, EINVAL);
236
        ipc_answer_0(callid, EINVAL);
241
        ipc_answer_0(rid, EINVAL);
237
        ipc_answer_0(rid, EINVAL);
242
        return;
238
        return;
Line 246... Line 242...
246
     * We can only send the client address space area PLB_SIZE bytes long.
242
     * We can only send the client address space area PLB_SIZE bytes long.
247
     */
243
     */
248
    if (size != PLB_SIZE) {
244
    if (size != PLB_SIZE) {
249
        dprintf("Client suggests wrong size of PFB, size = %d\n", size);
245
        dprintf("Client suggests wrong size of PFB, size = %d\n", size);
250
        list_remove(&fs_info->fs_link);
246
        list_remove(&fs_info->fs_link);
251
        fibril_dec_sercount();
-
 
252
        futex_up(&fs_head_futex);
247
        fibril_mutex_unlock(&fs_head_lock);
253
        ipc_hangup(fs_info->phone);
248
        ipc_hangup(fs_info->phone);
254
        free(fs_info);
249
        free(fs_info);
255
        ipc_answer_0(callid, EINVAL);
250
        ipc_answer_0(callid, EINVAL);
256
        ipc_answer_0(rid, EINVAL);
251
        ipc_answer_0(rid, EINVAL);
257
        return;
252
        return;
Line 271... Line 266...
271
     * system a global file system handle.
266
     * system a global file system handle.
272
     */
267
     */
273
    fs_info->fs_handle = (fs_handle_t) atomic_postinc(&fs_handle_next);
268
    fs_info->fs_handle = (fs_handle_t) atomic_postinc(&fs_handle_next);
274
    ipc_answer_1(rid, EOK, (ipcarg_t) fs_info->fs_handle);
269
    ipc_answer_1(rid, EOK, (ipcarg_t) fs_info->fs_handle);
275
   
270
   
276
    fibril_dec_sercount();
-
 
277
    futex_up(&fs_head_futex);
271
    fibril_mutex_unlock(&fs_head_lock);
278
   
272
   
279
    dprintf("\"%.*s\" filesystem successfully registered, handle=%d.\n",
273
    dprintf("\"%.*s\" filesystem successfully registered, handle=%d.\n",
280
        FS_NAME_MAXLEN, fs_info->vfs_info.name, fs_info->fs_handle);
274
        FS_NAME_MAXLEN, fs_info->vfs_info.name, fs_info->fs_handle);
281
   
-
 
282
    /* Process pending mount requests possibly waiting
-
 
283
     * for this filesystem implementation.
-
 
284
     */
-
 
285
    vfs_process_pending_mount();
-
 
286
}
275
}
287
 
276
 
288
/** For a given file system handle, implement policy for allocating a phone.
277
/** For a given file system handle, implement policy for allocating a phone.
289
 *
278
 *
290
 * @param handle    File system handle.
279
 * @param handle    File system handle.
Line 300... Line 289...
300
     * open any additional phones (even though that itself would be pretty
289
     * open any additional phones (even though that itself would be pretty
301
     * straightforward; housekeeping multiple open phones to a FS task would
290
     * straightforward; housekeeping multiple open phones to a FS task would
302
     * be more demanding). Instead, we simply take the respective
291
     * be more demanding). Instead, we simply take the respective
303
     * phone_futex and keep it until vfs_release_phone().
292
     * phone_futex and keep it until vfs_release_phone().
304
     */
293
     */
305
    futex_down(&fs_head_futex);
294
    fibril_mutex_lock(&fs_head_lock);
306
    link_t *cur;
295
    link_t *cur;
307
    fs_info_t *fs;
296
    fs_info_t *fs;
308
    for (cur = fs_head.next; cur != &fs_head; cur = cur->next) {
297
    for (cur = fs_head.next; cur != &fs_head; cur = cur->next) {
309
        fs = list_get_instance(cur, fs_info_t, fs_link);
298
        fs = list_get_instance(cur, fs_info_t, fs_link);
310
        if (fs->fs_handle == handle) {
299
        if (fs->fs_handle == handle) {
311
            futex_up(&fs_head_futex);
300
            fibril_mutex_unlock(&fs_head_lock);
312
            /*
-
 
313
             * For now, take the futex unconditionally.
-
 
314
             * Oh yeah, serialization rocks.
-
 
315
             * It will be up'ed in vfs_release_phone().
-
 
316
             */
-
 
317
            futex_down(&fs->phone_futex);
301
            fibril_mutex_lock(&fs->phone_lock);
318
            /*
-
 
319
             * Avoid deadlock with other fibrils in the same thread
-
 
320
             * by disabling fibril preemption.
-
 
321
             */
-
 
322
            fibril_inc_sercount();
-
 
323
            return fs->phone;
302
            return fs->phone;
324
        }
303
        }
325
    }
304
    }
326
    futex_up(&fs_head_futex);
305
    fibril_mutex_unlock(&fs_head_lock);
327
    return 0;
306
    return 0;
328
}
307
}
329
 
308
 
330
/** Tell VFS that the phone is in use for any request.
309
/** Tell VFS that the phone is in use for any request.
331
 *
310
 *
Line 333... Line 312...
333
 */
312
 */
334
void vfs_release_phone(int phone)
313
void vfs_release_phone(int phone)
335
{
314
{
336
    bool found = false;
315
    bool found = false;
337
 
316
 
338
    /*
-
 
339
     * Undo the fibril_inc_sercount() done in vfs_grab_phone().
-
 
340
     */
-
 
341
    fibril_dec_sercount();
-
 
342
   
-
 
343
    futex_down(&fs_head_futex);
317
    fibril_mutex_lock(&fs_head_lock);
344
    link_t *cur;
318
    link_t *cur;
345
    for (cur = fs_head.next; cur != &fs_head; cur = cur->next) {
319
    for (cur = fs_head.next; cur != &fs_head; cur = cur->next) {
346
        fs_info_t *fs = list_get_instance(cur, fs_info_t, fs_link);
320
        fs_info_t *fs = list_get_instance(cur, fs_info_t, fs_link);
347
        if (fs->phone == phone) {
321
        if (fs->phone == phone) {
348
            found = true;
322
            found = true;
349
            futex_up(&fs_head_futex);
323
            fibril_mutex_unlock(&fs_head_lock);
350
            futex_up(&fs->phone_futex);
324
            fibril_mutex_unlock(&fs->phone_lock);
351
            return;
325
            return;
352
        }
326
        }
353
    }
327
    }
354
    futex_up(&fs_head_futex);
328
    fibril_mutex_unlock(&fs_head_lock);
355
 
329
 
356
    /*
330
    /*
357
     * Not good to get here.
331
     * Not good to get here.
358
     */
332
     */
359
    assert(found == true);
333
    assert(found == true);
360
}
334
}
361
 
335
 
362
/** Convert file system name to its handle.
336
/** Convert file system name to its handle.
363
 *
337
 *
364
 * @param name      File system name.
338
 * @param name      File system name.
365
 * @param lock      If true, the function will down and up the
339
 * @param lock      If true, the function will lock and unlock the
366
 *          fs_head_futex.
340
 *          fs_head_lock.
367
 *
341
 *
368
 * @return      File system handle or zero if file system not found.
342
 * @return      File system handle or zero if file system not found.
369
 */
343
 */
370
fs_handle_t fs_name_to_handle(char *name, bool lock)
344
fs_handle_t fs_name_to_handle(char *name, bool lock)
371
{
345
{
372
    int handle = 0;
346
    int handle = 0;
373
   
347
   
374
    if (lock)
348
    if (lock)
375
        futex_down(&fs_head_futex);
349
        fibril_mutex_lock(&fs_head_lock);
376
    link_t *cur;
350
    link_t *cur;
377
    for (cur = fs_head.next; cur != &fs_head; cur = cur->next) {
351
    for (cur = fs_head.next; cur != &fs_head; cur = cur->next) {
378
        fs_info_t *fs = list_get_instance(cur, fs_info_t, fs_link);
352
        fs_info_t *fs = list_get_instance(cur, fs_info_t, fs_link);
379
        if (str_cmp(fs->vfs_info.name, name) == 0) {
353
        if (str_cmp(fs->vfs_info.name, name) == 0) {
380
            handle = fs->fs_handle;
354
            handle = fs->fs_handle;
381
            break;
355
            break;
382
        }
356
        }
383
    }
357
    }
384
    if (lock)
358
    if (lock)
385
        futex_up(&fs_head_futex);
359
        fibril_mutex_unlock(&fs_head_lock);
386
    return handle;
360
    return handle;
387
}
361
}
388
 
362
 
389
/**
363
/**
390
 * @}
364
 * @}