source: mainline/uspace/srv/fs/devfs/devfs_ops.c@ 1313ee9

lfn serial ticket/834-toolchain-update topic/msim-upgrade topic/simplify-dev-export
Last change on this file since 1313ee9 was 1313ee9, checked in by Martin Decky <martin@…>, 16 years ago

introduce device namespaces

  • add support for explicit open in libfs (needed by devfs, but also possibly for other filesystems which need to track some stateful information)
  • extend libfs to be more generic, make proper adjustments to libc, tmpfs and fat
  • various updates to make use of the device namespaces
  • code cleanup
  • Property mode set to 100644
File size: 17.0 KB
Line 
1/*
2 * Copyright (c) 2009 Martin Decky
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 fs
30 * @{
31 */
32
33/**
34 * @file devfs_ops.c
35 * @brief Implementation of VFS operations for the devfs file system server.
36 */
37
38#include <ipc/ipc.h>
39#include <bool.h>
40#include <errno.h>
41#include <malloc.h>
42#include <string.h>
43#include <libfs.h>
44#include <fibril_synch.h>
45#include <adt/hash_table.h>
46#include <ipc/devmap.h>
47#include <sys/stat.h>
48#include <libfs.h>
49#include <assert.h>
50#include "devfs.h"
51#include "devfs_ops.h"
52
53typedef struct {
54 devmap_handle_type_t type;
55 dev_handle_t handle;
56} devfs_node_t;
57
58/** Opened devices structure */
59typedef struct {
60 dev_handle_t handle;
61 int phone;
62 size_t refcount;
63 link_t link;
64} device_t;
65
66/** Hash table of opened devices */
67static hash_table_t devices;
68
69/** Hash table mutex */
70static FIBRIL_MUTEX_INITIALIZE(devices_mutex);
71
72#define DEVICES_KEYS 1
73#define DEVICES_KEY_HANDLE 0
74#define DEVICES_BUCKETS 256
75
76/* Implementation of hash table interface for the nodes hash table. */
77static hash_index_t devices_hash(unsigned long key[])
78{
79 return key[DEVICES_KEY_HANDLE] % DEVICES_BUCKETS;
80}
81
82static int devices_compare(unsigned long key[], hash_count_t keys, link_t *item)
83{
84 device_t *dev = hash_table_get_instance(item, device_t, link);
85 return (dev->handle == (dev_handle_t) key[DEVICES_KEY_HANDLE]);
86}
87
88static void devices_remove_callback(link_t *item)
89{
90 free(hash_table_get_instance(item, device_t, link));
91}
92
93static hash_table_operations_t devices_ops = {
94 .hash = devices_hash,
95 .compare = devices_compare,
96 .remove_callback = devices_remove_callback
97};
98
99static int devfs_node_get_internal(fs_node_t **rfn, devmap_handle_type_t type,
100 dev_handle_t handle)
101{
102 devfs_node_t *node = (devfs_node_t *) malloc(sizeof(devfs_node_t));
103 if (node == NULL) {
104 *rfn = NULL;
105 return ENOMEM;
106 }
107
108 *rfn = (fs_node_t *) malloc(sizeof(fs_node_t));
109 if (*rfn == NULL) {
110 free(node);
111 *rfn = NULL;
112 return ENOMEM;
113 }
114
115 fs_node_initialize(*rfn);
116 node->type = type;
117 node->handle = handle;
118
119 (*rfn)->data = node;
120 return EOK;
121}
122
123static int devfs_root_get(fs_node_t **rfn, dev_handle_t dev_handle)
124{
125 return devfs_node_get_internal(rfn, DEV_HANDLE_NONE, 0);
126}
127
128static int devfs_match(fs_node_t **rfn, fs_node_t *pfn, const char *component)
129{
130 devfs_node_t *node = (devfs_node_t *) pfn->data;
131
132 if (node->handle == 0) {
133 /* Root directory */
134
135 dev_desc_t *devs;
136 size_t count = devmap_get_namespaces(&devs);
137
138 if (count > 0) {
139 size_t pos;
140 for (pos = 0; pos < count; pos++) {
141 /* Ignore root namespace */
142 if (str_cmp(devs[pos].name, "") == 0)
143 continue;
144
145 if (str_cmp(devs[pos].name, component) == 0) {
146 free(devs);
147 return devfs_node_get_internal(rfn, DEV_HANDLE_NAMESPACE, devs[pos].handle);
148 }
149 }
150
151 free(devs);
152 }
153
154 /* Search root namespace */
155 dev_handle_t namespace;
156 if (devmap_namespace_get_handle("", &namespace, 0) == EOK) {
157 count = devmap_get_devices(namespace, &devs);
158
159 if (count > 0) {
160 size_t pos;
161 for (pos = 0; pos < count; pos++) {
162 if (str_cmp(devs[pos].name, component) == 0) {
163 free(devs);
164 return devfs_node_get_internal(rfn, DEV_HANDLE_DEVICE, devs[pos].handle);
165 }
166 }
167
168 free(devs);
169 }
170 }
171
172 *rfn = NULL;
173 return EOK;
174 }
175
176 if (node->type == DEV_HANDLE_NAMESPACE) {
177 /* Namespace directory */
178
179 dev_desc_t *devs;
180 size_t count = devmap_get_devices(node->handle, &devs);
181 if (count > 0) {
182 size_t pos;
183 for (pos = 0; pos < count; pos++) {
184 if (str_cmp(devs[pos].name, component) == 0) {
185 free(devs);
186 return devfs_node_get_internal(rfn, DEV_HANDLE_DEVICE, devs[pos].handle);
187 }
188 }
189
190 free(devs);
191 }
192
193 *rfn = NULL;
194 return EOK;
195 }
196
197 *rfn = NULL;
198 return EOK;
199}
200
201static int devfs_node_get(fs_node_t **rfn, dev_handle_t dev_handle, fs_index_t index)
202{
203 return devfs_node_get_internal(rfn, devmap_handle_probe(index), index);
204}
205
206static int devfs_node_open(fs_node_t *fn)
207{
208 devfs_node_t *node = (devfs_node_t *) fn->data;
209
210 if (node->handle == 0) {
211 /* Root directory */
212 return EOK;
213 }
214
215 devmap_handle_type_t type = devmap_handle_probe(node->handle);
216
217 if (type == DEV_HANDLE_NAMESPACE) {
218 /* Namespace directory */
219 return EOK;
220 }
221
222 if (type == DEV_HANDLE_DEVICE) {
223 /* Device node */
224
225 unsigned long key[] = {
226 [DEVICES_KEY_HANDLE] = (unsigned long) node->handle
227 };
228
229 fibril_mutex_lock(&devices_mutex);
230 link_t *lnk = hash_table_find(&devices, key);
231 if (lnk == NULL) {
232 device_t *dev = (device_t *) malloc(sizeof(device_t));
233 if (dev == NULL) {
234 fibril_mutex_unlock(&devices_mutex);
235 return ENOMEM;
236 }
237
238 int phone = devmap_device_connect(node->handle, 0);
239 if (phone < 0) {
240 fibril_mutex_unlock(&devices_mutex);
241 free(dev);
242 return ENOENT;
243 }
244
245 dev->handle = node->handle;
246 dev->phone = phone;
247 dev->refcount = 1;
248
249 hash_table_insert(&devices, key, &dev->link);
250 } else {
251 device_t *dev = hash_table_get_instance(lnk, device_t, link);
252 dev->refcount++;
253 }
254
255 fibril_mutex_unlock(&devices_mutex);
256
257 return EOK;
258 }
259
260 return ENOENT;
261}
262
263static int devfs_node_put(fs_node_t *fn)
264{
265 free(fn->data);
266 free(fn);
267 return EOK;
268}
269
270static int devfs_create_node(fs_node_t **rfn, dev_handle_t dev_handle, int lflag)
271{
272 assert((lflag & L_FILE) ^ (lflag & L_DIRECTORY));
273
274 *rfn = NULL;
275 return ENOTSUP;
276}
277
278static int devfs_destroy_node(fs_node_t *fn)
279{
280 return ENOTSUP;
281}
282
283static int devfs_link_node(fs_node_t *pfn, fs_node_t *cfn, const char *nm)
284{
285 return ENOTSUP;
286}
287
288static int devfs_unlink_node(fs_node_t *pfn, fs_node_t *cfn, const char *nm)
289{
290 return ENOTSUP;
291}
292
293static int devfs_has_children(bool *has_children, fs_node_t *fn)
294{
295 devfs_node_t *node = (devfs_node_t *) fn->data;
296
297 if (node->handle == 0) {
298 size_t count = devmap_count_namespaces();
299 if (count > 0) {
300 *has_children = true;
301 return EOK;
302 }
303
304 /* Root namespace */
305 dev_handle_t namespace;
306 if (devmap_namespace_get_handle("", &namespace, 0) == EOK) {
307 count = devmap_count_devices(namespace);
308 if (count > 0) {
309 *has_children = true;
310 return EOK;
311 }
312 }
313
314 *has_children = false;
315 return EOK;
316 }
317
318 if (node->type == DEV_HANDLE_NAMESPACE) {
319 size_t count = devmap_count_devices(node->handle);
320 if (count > 0) {
321 *has_children = true;
322 return EOK;
323 }
324
325 *has_children = false;
326 return EOK;
327 }
328
329 *has_children = false;
330 return EOK;
331}
332
333static fs_index_t devfs_index_get(fs_node_t *fn)
334{
335 devfs_node_t *node = (devfs_node_t *) fn->data;
336 return node->handle;
337}
338
339static size_t devfs_size_get(fs_node_t *fn)
340{
341 return 0;
342}
343
344static unsigned int devfs_lnkcnt_get(fs_node_t *fn)
345{
346 devfs_node_t *node = (devfs_node_t *) fn->data;
347
348 if (node->handle == 0)
349 return 0;
350
351 return 1;
352}
353
354static char devfs_plb_get_char(unsigned pos)
355{
356 return devfs_reg.plb_ro[pos % PLB_SIZE];
357}
358
359static bool devfs_is_directory(fs_node_t *fn)
360{
361 devfs_node_t *node = (devfs_node_t *) fn->data;
362
363 return ((node->type == DEV_HANDLE_NONE) || (node->type == DEV_HANDLE_NAMESPACE));
364}
365
366static bool devfs_is_file(fs_node_t *fn)
367{
368 devfs_node_t *node = (devfs_node_t *) fn->data;
369
370 return (node->type == DEV_HANDLE_DEVICE);
371}
372
373static dev_handle_t devfs_device_get(fs_node_t *fn)
374{
375 devfs_node_t *node = (devfs_node_t *) fn->data;
376
377 if (node->type == DEV_HANDLE_DEVICE)
378 return node->handle;
379
380 return 0;
381}
382
383/** libfs operations */
384libfs_ops_t devfs_libfs_ops = {
385 .root_get = devfs_root_get,
386 .match = devfs_match,
387 .node_get = devfs_node_get,
388 .node_open = devfs_node_open,
389 .node_put = devfs_node_put,
390 .create = devfs_create_node,
391 .destroy = devfs_destroy_node,
392 .link = devfs_link_node,
393 .unlink = devfs_unlink_node,
394 .has_children = devfs_has_children,
395 .index_get = devfs_index_get,
396 .size_get = devfs_size_get,
397 .lnkcnt_get = devfs_lnkcnt_get,
398 .plb_get_char = devfs_plb_get_char,
399 .is_directory = devfs_is_directory,
400 .is_file = devfs_is_file,
401 .device_get = devfs_device_get
402};
403
404bool devfs_init(void)
405{
406 if (!hash_table_create(&devices, DEVICES_BUCKETS,
407 DEVICES_KEYS, &devices_ops))
408 return false;
409
410 if (devmap_get_phone(DEVMAP_CLIENT, IPC_FLAG_BLOCKING) < 0)
411 return false;
412
413 return true;
414}
415
416void devfs_mounted(ipc_callid_t rid, ipc_call_t *request)
417{
418 char *opts;
419
420 /* Accept the mount options */
421 ipcarg_t retval = async_data_string_receive(&opts, 0);
422 if (retval != EOK) {
423 ipc_answer_0(rid, retval);
424 return;
425 }
426
427 free(opts);
428 ipc_answer_3(rid, EOK, 0, 0, 0);
429}
430
431void devfs_mount(ipc_callid_t rid, ipc_call_t *request)
432{
433 libfs_mount(&devfs_libfs_ops, devfs_reg.fs_handle, rid, request);
434}
435
436void devfs_lookup(ipc_callid_t rid, ipc_call_t *request)
437{
438 libfs_lookup(&devfs_libfs_ops, devfs_reg.fs_handle, rid, request);
439}
440
441void devfs_open_node(ipc_callid_t rid, ipc_call_t *request)
442{
443 libfs_open_node(&devfs_libfs_ops, devfs_reg.fs_handle, rid, request);
444}
445
446void devfs_stat(ipc_callid_t rid, ipc_call_t *request)
447{
448 libfs_stat(&devfs_libfs_ops, devfs_reg.fs_handle, rid, request);
449}
450
451void devfs_read(ipc_callid_t rid, ipc_call_t *request)
452{
453 fs_index_t index = (fs_index_t) IPC_GET_ARG2(*request);
454 off_t pos = (off_t) IPC_GET_ARG3(*request);
455
456 if (index == 0) {
457 ipc_callid_t callid;
458 size_t size;
459 if (!async_data_read_receive(&callid, &size)) {
460 ipc_answer_0(callid, EINVAL);
461 ipc_answer_0(rid, EINVAL);
462 return;
463 }
464
465 dev_desc_t *desc;
466 size_t count = devmap_get_namespaces(&desc);
467
468 /* Get rid of root namespace */
469 size_t i;
470 for (i = 0; i < count; i++) {
471 if (str_cmp(desc[i].name, "") == 0) {
472 if (pos >= i)
473 pos++;
474
475 break;
476 }
477 }
478
479 if (pos < count) {
480 async_data_read_finalize(callid, desc[pos].name, str_size(desc[pos].name) + 1);
481 free(desc);
482 ipc_answer_1(rid, EOK, 1);
483 return;
484 }
485
486 free(desc);
487 pos -= count;
488
489 /* Search root namespace */
490 dev_handle_t namespace;
491 if (devmap_namespace_get_handle("", &namespace, 0) == EOK) {
492 count = devmap_get_devices(namespace, &desc);
493
494 if (pos < count) {
495 async_data_read_finalize(callid, desc[pos].name, str_size(desc[pos].name) + 1);
496 free(desc);
497 ipc_answer_1(rid, EOK, 1);
498 return;
499 }
500
501 free(desc);
502 }
503
504 ipc_answer_0(callid, ENOENT);
505 ipc_answer_1(rid, ENOENT, 0);
506 return;
507 }
508
509 devmap_handle_type_t type = devmap_handle_probe(index);
510
511 if (type == DEV_HANDLE_NAMESPACE) {
512 /* Namespace directory */
513 ipc_callid_t callid;
514 size_t size;
515 if (!async_data_read_receive(&callid, &size)) {
516 ipc_answer_0(callid, EINVAL);
517 ipc_answer_0(rid, EINVAL);
518 return;
519 }
520
521 dev_desc_t *desc;
522 size_t count = devmap_get_devices(index, &desc);
523
524 if (pos < count) {
525 async_data_read_finalize(callid, desc[pos].name, str_size(desc[pos].name) + 1);
526 free(desc);
527 ipc_answer_1(rid, EOK, 1);
528 return;
529 }
530
531 free(desc);
532 ipc_answer_0(callid, ENOENT);
533 ipc_answer_1(rid, ENOENT, 0);
534 return;
535 }
536
537 if (type == DEV_HANDLE_DEVICE) {
538 /* Device node */
539
540 unsigned long key[] = {
541 [DEVICES_KEY_HANDLE] = (unsigned long) index
542 };
543
544 fibril_mutex_lock(&devices_mutex);
545 link_t *lnk = hash_table_find(&devices, key);
546 if (lnk == NULL) {
547 fibril_mutex_unlock(&devices_mutex);
548 ipc_answer_0(rid, ENOENT);
549 return;
550 }
551
552 device_t *dev = hash_table_get_instance(lnk, device_t, link);
553
554 ipc_callid_t callid;
555 if (!async_data_read_receive(&callid, NULL)) {
556 fibril_mutex_unlock(&devices_mutex);
557 ipc_answer_0(callid, EINVAL);
558 ipc_answer_0(rid, EINVAL);
559 return;
560 }
561
562 /* Make a request at the driver */
563 ipc_call_t answer;
564 aid_t msg = async_send_3(dev->phone, IPC_GET_METHOD(*request),
565 IPC_GET_ARG1(*request), IPC_GET_ARG2(*request),
566 IPC_GET_ARG3(*request), &answer);
567
568 /* Forward the IPC_M_DATA_READ request to the driver */
569 ipc_forward_fast(callid, dev->phone, 0, 0, 0, IPC_FF_ROUTE_FROM_ME);
570 fibril_mutex_unlock(&devices_mutex);
571
572 /* Wait for reply from the driver. */
573 ipcarg_t rc;
574 async_wait_for(msg, &rc);
575 size_t bytes = IPC_GET_ARG1(answer);
576
577 /* Driver reply is the final result of the whole operation */
578 ipc_answer_1(rid, rc, bytes);
579 return;
580 }
581
582 ipc_answer_0(rid, ENOENT);
583}
584
585void devfs_write(ipc_callid_t rid, ipc_call_t *request)
586{
587 fs_index_t index = (fs_index_t) IPC_GET_ARG2(*request);
588 off_t pos = (off_t) IPC_GET_ARG3(*request);
589
590 if (index == 0) {
591 ipc_answer_0(rid, ENOTSUP);
592 return;
593 }
594
595 devmap_handle_type_t type = devmap_handle_probe(index);
596
597 if (type == DEV_HANDLE_NAMESPACE) {
598 /* Namespace directory */
599 ipc_answer_0(rid, ENOTSUP);
600 return;
601 }
602
603 if (type == DEV_HANDLE_DEVICE) {
604 /* Device node */
605 unsigned long key[] = {
606 [DEVICES_KEY_HANDLE] = (unsigned long) index
607 };
608
609 fibril_mutex_lock(&devices_mutex);
610 link_t *lnk = hash_table_find(&devices, key);
611 if (lnk == NULL) {
612 fibril_mutex_unlock(&devices_mutex);
613 ipc_answer_0(rid, ENOENT);
614 return;
615 }
616
617 device_t *dev = hash_table_get_instance(lnk, device_t, link);
618
619 ipc_callid_t callid;
620 if (!async_data_write_receive(&callid, NULL)) {
621 fibril_mutex_unlock(&devices_mutex);
622 ipc_answer_0(callid, EINVAL);
623 ipc_answer_0(rid, EINVAL);
624 return;
625 }
626
627 /* Make a request at the driver */
628 ipc_call_t answer;
629 aid_t msg = async_send_3(dev->phone, IPC_GET_METHOD(*request),
630 IPC_GET_ARG1(*request), IPC_GET_ARG2(*request),
631 IPC_GET_ARG3(*request), &answer);
632
633 /* Forward the IPC_M_DATA_WRITE request to the driver */
634 ipc_forward_fast(callid, dev->phone, 0, 0, 0, IPC_FF_ROUTE_FROM_ME);
635
636 fibril_mutex_unlock(&devices_mutex);
637
638 /* Wait for reply from the driver. */
639 ipcarg_t rc;
640 async_wait_for(msg, &rc);
641 size_t bytes = IPC_GET_ARG1(answer);
642
643 /* Driver reply is the final result of the whole operation */
644 ipc_answer_1(rid, rc, bytes);
645 return;
646 }
647
648 ipc_answer_0(rid, ENOENT);
649}
650
651void devfs_truncate(ipc_callid_t rid, ipc_call_t *request)
652{
653 ipc_answer_0(rid, ENOTSUP);
654}
655
656void devfs_close(ipc_callid_t rid, ipc_call_t *request)
657{
658 fs_index_t index = (fs_index_t) IPC_GET_ARG2(*request);
659
660 if (index == 0) {
661 ipc_answer_0(rid, EOK);
662 return;
663 }
664
665 devmap_handle_type_t type = devmap_handle_probe(index);
666
667 if (type == DEV_HANDLE_NAMESPACE) {
668 /* Namespace directory */
669 ipc_answer_0(rid, EOK);
670 return;
671 }
672
673 if (type == DEV_HANDLE_DEVICE) {
674 unsigned long key[] = {
675 [DEVICES_KEY_HANDLE] = (unsigned long) index
676 };
677
678 fibril_mutex_lock(&devices_mutex);
679 link_t *lnk = hash_table_find(&devices, key);
680 if (lnk == NULL) {
681 fibril_mutex_unlock(&devices_mutex);
682 ipc_answer_0(rid, ENOENT);
683 return;
684 }
685
686 device_t *dev = hash_table_get_instance(lnk, device_t, link);
687 dev->refcount--;
688
689 if (dev->refcount == 0) {
690 ipc_hangup(dev->phone);
691 hash_table_remove(&devices, key, DEVICES_KEYS);
692 }
693
694 fibril_mutex_unlock(&devices_mutex);
695
696 ipc_answer_0(rid, EOK);
697 return;
698 }
699
700 ipc_answer_0(rid, ENOENT);
701}
702
703void devfs_sync(ipc_callid_t rid, ipc_call_t *request)
704{
705 fs_index_t index = (fs_index_t) IPC_GET_ARG2(*request);
706
707 if (index == 0) {
708 ipc_answer_0(rid, EOK);
709 return;
710 }
711
712 devmap_handle_type_t type = devmap_handle_probe(index);
713
714 if (type == DEV_HANDLE_NAMESPACE) {
715 /* Namespace directory */
716 ipc_answer_0(rid, EOK);
717 return;
718 }
719
720 if (type == DEV_HANDLE_DEVICE) {
721 unsigned long key[] = {
722 [DEVICES_KEY_HANDLE] = (unsigned long) index
723 };
724
725 fibril_mutex_lock(&devices_mutex);
726 link_t *lnk = hash_table_find(&devices, key);
727 if (lnk == NULL) {
728 fibril_mutex_unlock(&devices_mutex);
729 ipc_answer_0(rid, ENOENT);
730 return;
731 }
732
733 device_t *dev = hash_table_get_instance(lnk, device_t, link);
734
735 /* Make a request at the driver */
736 ipc_call_t answer;
737 aid_t msg = async_send_2(dev->phone, IPC_GET_METHOD(*request),
738 IPC_GET_ARG1(*request), IPC_GET_ARG2(*request), &answer);
739
740 fibril_mutex_unlock(&devices_mutex);
741
742 /* Wait for reply from the driver */
743 ipcarg_t rc;
744 async_wait_for(msg, &rc);
745
746 /* Driver reply is the final result of the whole operation */
747 ipc_answer_0(rid, rc);
748 return;
749 }
750
751 ipc_answer_0(rid, ENOENT);
752}
753
754void devfs_destroy(ipc_callid_t rid, ipc_call_t *request)
755{
756 ipc_answer_0(rid, ENOTSUP);
757}
758
759/**
760 * @}
761 */
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