firewire: cdev: reduce stack usage by ioctl_dispatch
[linux-2.6.git] / drivers / firewire / core-cdev.c
1 /*
2  * Char device for device raw access
3  *
4  * Copyright (C) 2005-2007  Kristian Hoegsberg <krh@bitplanet.net>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software Foundation,
18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19  */
20
21 #include <linux/compat.h>
22 #include <linux/delay.h>
23 #include <linux/device.h>
24 #include <linux/errno.h>
25 #include <linux/firewire.h>
26 #include <linux/firewire-cdev.h>
27 #include <linux/idr.h>
28 #include <linux/jiffies.h>
29 #include <linux/kernel.h>
30 #include <linux/kref.h>
31 #include <linux/mm.h>
32 #include <linux/module.h>
33 #include <linux/mutex.h>
34 #include <linux/poll.h>
35 #include <linux/preempt.h>
36 #include <linux/spinlock.h>
37 #include <linux/time.h>
38 #include <linux/uaccess.h>
39 #include <linux/vmalloc.h>
40 #include <linux/wait.h>
41 #include <linux/workqueue.h>
42
43 #include <asm/system.h>
44
45 #include "core.h"
46
47 struct client {
48         u32 version;
49         struct fw_device *device;
50
51         spinlock_t lock;
52         bool in_shutdown;
53         struct idr resource_idr;
54         struct list_head event_list;
55         wait_queue_head_t wait;
56         u64 bus_reset_closure;
57
58         struct fw_iso_context *iso_context;
59         u64 iso_closure;
60         struct fw_iso_buffer buffer;
61         unsigned long vm_start;
62
63         struct list_head link;
64         struct kref kref;
65 };
66
67 static inline void client_get(struct client *client)
68 {
69         kref_get(&client->kref);
70 }
71
72 static void client_release(struct kref *kref)
73 {
74         struct client *client = container_of(kref, struct client, kref);
75
76         fw_device_put(client->device);
77         kfree(client);
78 }
79
80 static void client_put(struct client *client)
81 {
82         kref_put(&client->kref, client_release);
83 }
84
85 struct client_resource;
86 typedef void (*client_resource_release_fn_t)(struct client *,
87                                              struct client_resource *);
88 struct client_resource {
89         client_resource_release_fn_t release;
90         int handle;
91 };
92
93 struct address_handler_resource {
94         struct client_resource resource;
95         struct fw_address_handler handler;
96         __u64 closure;
97         struct client *client;
98 };
99
100 struct outbound_transaction_resource {
101         struct client_resource resource;
102         struct fw_transaction transaction;
103 };
104
105 struct inbound_transaction_resource {
106         struct client_resource resource;
107         struct fw_request *request;
108         void *data;
109         size_t length;
110 };
111
112 struct descriptor_resource {
113         struct client_resource resource;
114         struct fw_descriptor descriptor;
115         u32 data[0];
116 };
117
118 struct iso_resource {
119         struct client_resource resource;
120         struct client *client;
121         /* Schedule work and access todo only with client->lock held. */
122         struct delayed_work work;
123         enum {ISO_RES_ALLOC, ISO_RES_REALLOC, ISO_RES_DEALLOC,
124               ISO_RES_ALLOC_ONCE, ISO_RES_DEALLOC_ONCE,} todo;
125         int generation;
126         u64 channels;
127         s32 bandwidth;
128         __be32 transaction_data[2];
129         struct iso_resource_event *e_alloc, *e_dealloc;
130 };
131
132 static void release_iso_resource(struct client *, struct client_resource *);
133
134 static void schedule_iso_resource(struct iso_resource *r, unsigned long delay)
135 {
136         client_get(r->client);
137         if (!schedule_delayed_work(&r->work, delay))
138                 client_put(r->client);
139 }
140
141 static void schedule_if_iso_resource(struct client_resource *resource)
142 {
143         if (resource->release == release_iso_resource)
144                 schedule_iso_resource(container_of(resource,
145                                         struct iso_resource, resource), 0);
146 }
147
148 /*
149  * dequeue_event() just kfree()'s the event, so the event has to be
150  * the first field in a struct XYZ_event.
151  */
152 struct event {
153         struct { void *data; size_t size; } v[2];
154         struct list_head link;
155 };
156
157 struct bus_reset_event {
158         struct event event;
159         struct fw_cdev_event_bus_reset reset;
160 };
161
162 struct outbound_transaction_event {
163         struct event event;
164         struct client *client;
165         struct outbound_transaction_resource r;
166         struct fw_cdev_event_response response;
167 };
168
169 struct inbound_transaction_event {
170         struct event event;
171         struct fw_cdev_event_request request;
172 };
173
174 struct iso_interrupt_event {
175         struct event event;
176         struct fw_cdev_event_iso_interrupt interrupt;
177 };
178
179 struct iso_resource_event {
180         struct event event;
181         struct fw_cdev_event_iso_resource iso_resource;
182 };
183
184 static inline void __user *u64_to_uptr(__u64 value)
185 {
186         return (void __user *)(unsigned long)value;
187 }
188
189 static inline __u64 uptr_to_u64(void __user *ptr)
190 {
191         return (__u64)(unsigned long)ptr;
192 }
193
194 static int fw_device_op_open(struct inode *inode, struct file *file)
195 {
196         struct fw_device *device;
197         struct client *client;
198
199         device = fw_device_get_by_devt(inode->i_rdev);
200         if (device == NULL)
201                 return -ENODEV;
202
203         if (fw_device_is_shutdown(device)) {
204                 fw_device_put(device);
205                 return -ENODEV;
206         }
207
208         client = kzalloc(sizeof(*client), GFP_KERNEL);
209         if (client == NULL) {
210                 fw_device_put(device);
211                 return -ENOMEM;
212         }
213
214         client->device = device;
215         spin_lock_init(&client->lock);
216         idr_init(&client->resource_idr);
217         INIT_LIST_HEAD(&client->event_list);
218         init_waitqueue_head(&client->wait);
219         kref_init(&client->kref);
220
221         file->private_data = client;
222
223         mutex_lock(&device->client_list_mutex);
224         list_add_tail(&client->link, &device->client_list);
225         mutex_unlock(&device->client_list_mutex);
226
227         return 0;
228 }
229
230 static void queue_event(struct client *client, struct event *event,
231                         void *data0, size_t size0, void *data1, size_t size1)
232 {
233         unsigned long flags;
234
235         event->v[0].data = data0;
236         event->v[0].size = size0;
237         event->v[1].data = data1;
238         event->v[1].size = size1;
239
240         spin_lock_irqsave(&client->lock, flags);
241         if (client->in_shutdown)
242                 kfree(event);
243         else
244                 list_add_tail(&event->link, &client->event_list);
245         spin_unlock_irqrestore(&client->lock, flags);
246
247         wake_up_interruptible(&client->wait);
248 }
249
250 static int dequeue_event(struct client *client,
251                          char __user *buffer, size_t count)
252 {
253         struct event *event;
254         size_t size, total;
255         int i, ret;
256
257         ret = wait_event_interruptible(client->wait,
258                         !list_empty(&client->event_list) ||
259                         fw_device_is_shutdown(client->device));
260         if (ret < 0)
261                 return ret;
262
263         if (list_empty(&client->event_list) &&
264                        fw_device_is_shutdown(client->device))
265                 return -ENODEV;
266
267         spin_lock_irq(&client->lock);
268         event = list_first_entry(&client->event_list, struct event, link);
269         list_del(&event->link);
270         spin_unlock_irq(&client->lock);
271
272         total = 0;
273         for (i = 0; i < ARRAY_SIZE(event->v) && total < count; i++) {
274                 size = min(event->v[i].size, count - total);
275                 if (copy_to_user(buffer + total, event->v[i].data, size)) {
276                         ret = -EFAULT;
277                         goto out;
278                 }
279                 total += size;
280         }
281         ret = total;
282
283  out:
284         kfree(event);
285
286         return ret;
287 }
288
289 static ssize_t fw_device_op_read(struct file *file, char __user *buffer,
290                                  size_t count, loff_t *offset)
291 {
292         struct client *client = file->private_data;
293
294         return dequeue_event(client, buffer, count);
295 }
296
297 static void fill_bus_reset_event(struct fw_cdev_event_bus_reset *event,
298                                  struct client *client)
299 {
300         struct fw_card *card = client->device->card;
301
302         spin_lock_irq(&card->lock);
303
304         event->closure       = client->bus_reset_closure;
305         event->type          = FW_CDEV_EVENT_BUS_RESET;
306         event->generation    = client->device->generation;
307         event->node_id       = client->device->node_id;
308         event->local_node_id = card->local_node->node_id;
309         event->bm_node_id    = 0; /* FIXME: We don't track the BM. */
310         event->irm_node_id   = card->irm_node->node_id;
311         event->root_node_id  = card->root_node->node_id;
312
313         spin_unlock_irq(&card->lock);
314 }
315
316 static void for_each_client(struct fw_device *device,
317                             void (*callback)(struct client *client))
318 {
319         struct client *c;
320
321         mutex_lock(&device->client_list_mutex);
322         list_for_each_entry(c, &device->client_list, link)
323                 callback(c);
324         mutex_unlock(&device->client_list_mutex);
325 }
326
327 static int schedule_reallocations(int id, void *p, void *data)
328 {
329         schedule_if_iso_resource(p);
330
331         return 0;
332 }
333
334 static void queue_bus_reset_event(struct client *client)
335 {
336         struct bus_reset_event *e;
337
338         e = kzalloc(sizeof(*e), GFP_KERNEL);
339         if (e == NULL) {
340                 fw_notify("Out of memory when allocating bus reset event\n");
341                 return;
342         }
343
344         fill_bus_reset_event(&e->reset, client);
345
346         queue_event(client, &e->event,
347                     &e->reset, sizeof(e->reset), NULL, 0);
348
349         spin_lock_irq(&client->lock);
350         idr_for_each(&client->resource_idr, schedule_reallocations, client);
351         spin_unlock_irq(&client->lock);
352 }
353
354 void fw_device_cdev_update(struct fw_device *device)
355 {
356         for_each_client(device, queue_bus_reset_event);
357 }
358
359 static void wake_up_client(struct client *client)
360 {
361         wake_up_interruptible(&client->wait);
362 }
363
364 void fw_device_cdev_remove(struct fw_device *device)
365 {
366         for_each_client(device, wake_up_client);
367 }
368
369 static int ioctl_get_info(struct client *client, void *buffer)
370 {
371         struct fw_cdev_get_info *get_info = buffer;
372         struct fw_cdev_event_bus_reset bus_reset;
373         unsigned long ret = 0;
374
375         client->version = get_info->version;
376         get_info->version = FW_CDEV_VERSION;
377         get_info->card = client->device->card->index;
378
379         down_read(&fw_device_rwsem);
380
381         if (get_info->rom != 0) {
382                 void __user *uptr = u64_to_uptr(get_info->rom);
383                 size_t want = get_info->rom_length;
384                 size_t have = client->device->config_rom_length * 4;
385
386                 ret = copy_to_user(uptr, client->device->config_rom,
387                                    min(want, have));
388         }
389         get_info->rom_length = client->device->config_rom_length * 4;
390
391         up_read(&fw_device_rwsem);
392
393         if (ret != 0)
394                 return -EFAULT;
395
396         client->bus_reset_closure = get_info->bus_reset_closure;
397         if (get_info->bus_reset != 0) {
398                 void __user *uptr = u64_to_uptr(get_info->bus_reset);
399
400                 fill_bus_reset_event(&bus_reset, client);
401                 if (copy_to_user(uptr, &bus_reset, sizeof(bus_reset)))
402                         return -EFAULT;
403         }
404
405         return 0;
406 }
407
408 static int add_client_resource(struct client *client,
409                                struct client_resource *resource, gfp_t gfp_mask)
410 {
411         unsigned long flags;
412         int ret;
413
414  retry:
415         if (idr_pre_get(&client->resource_idr, gfp_mask) == 0)
416                 return -ENOMEM;
417
418         spin_lock_irqsave(&client->lock, flags);
419         if (client->in_shutdown)
420                 ret = -ECANCELED;
421         else
422                 ret = idr_get_new(&client->resource_idr, resource,
423                                   &resource->handle);
424         if (ret >= 0) {
425                 client_get(client);
426                 schedule_if_iso_resource(resource);
427         }
428         spin_unlock_irqrestore(&client->lock, flags);
429
430         if (ret == -EAGAIN)
431                 goto retry;
432
433         return ret < 0 ? ret : 0;
434 }
435
436 static int release_client_resource(struct client *client, u32 handle,
437                                    client_resource_release_fn_t release,
438                                    struct client_resource **return_resource)
439 {
440         struct client_resource *resource;
441
442         spin_lock_irq(&client->lock);
443         if (client->in_shutdown)
444                 resource = NULL;
445         else
446                 resource = idr_find(&client->resource_idr, handle);
447         if (resource && resource->release == release)
448                 idr_remove(&client->resource_idr, handle);
449         spin_unlock_irq(&client->lock);
450
451         if (!(resource && resource->release == release))
452                 return -EINVAL;
453
454         if (return_resource)
455                 *return_resource = resource;
456         else
457                 resource->release(client, resource);
458
459         client_put(client);
460
461         return 0;
462 }
463
464 static void release_transaction(struct client *client,
465                                 struct client_resource *resource)
466 {
467         struct outbound_transaction_resource *r = container_of(resource,
468                         struct outbound_transaction_resource, resource);
469
470         fw_cancel_transaction(client->device->card, &r->transaction);
471 }
472
473 static void complete_transaction(struct fw_card *card, int rcode,
474                                  void *payload, size_t length, void *data)
475 {
476         struct outbound_transaction_event *e = data;
477         struct fw_cdev_event_response *rsp = &e->response;
478         struct client *client = e->client;
479         unsigned long flags;
480
481         if (length < rsp->length)
482                 rsp->length = length;
483         if (rcode == RCODE_COMPLETE)
484                 memcpy(rsp->data, payload, rsp->length);
485
486         spin_lock_irqsave(&client->lock, flags);
487         /*
488          * 1. If called while in shutdown, the idr tree must be left untouched.
489          *    The idr handle will be removed and the client reference will be
490          *    dropped later.
491          * 2. If the call chain was release_client_resource ->
492          *    release_transaction -> complete_transaction (instead of a normal
493          *    conclusion of the transaction), i.e. if this resource was already
494          *    unregistered from the idr, the client reference will be dropped
495          *    by release_client_resource and we must not drop it here.
496          */
497         if (!client->in_shutdown &&
498             idr_find(&client->resource_idr, e->r.resource.handle)) {
499                 idr_remove(&client->resource_idr, e->r.resource.handle);
500                 /* Drop the idr's reference */
501                 client_put(client);
502         }
503         spin_unlock_irqrestore(&client->lock, flags);
504
505         rsp->type = FW_CDEV_EVENT_RESPONSE;
506         rsp->rcode = rcode;
507
508         /*
509          * In the case that sizeof(*rsp) doesn't align with the position of the
510          * data, and the read is short, preserve an extra copy of the data
511          * to stay compatible with a pre-2.6.27 bug.  Since the bug is harmless
512          * for short reads and some apps depended on it, this is both safe
513          * and prudent for compatibility.
514          */
515         if (rsp->length <= sizeof(*rsp) - offsetof(typeof(*rsp), data))
516                 queue_event(client, &e->event, rsp, sizeof(*rsp),
517                             rsp->data, rsp->length);
518         else
519                 queue_event(client, &e->event, rsp, sizeof(*rsp) + rsp->length,
520                             NULL, 0);
521
522         /* Drop the transaction callback's reference */
523         client_put(client);
524 }
525
526 static int init_request(struct client *client,
527                         struct fw_cdev_send_request *request,
528                         int destination_id, int speed)
529 {
530         struct outbound_transaction_event *e;
531         int ret;
532
533         if (request->tcode != TCODE_STREAM_DATA &&
534             (request->length > 4096 || request->length > 512 << speed))
535                 return -EIO;
536
537         e = kmalloc(sizeof(*e) + request->length, GFP_KERNEL);
538         if (e == NULL)
539                 return -ENOMEM;
540
541         e->client = client;
542         e->response.length = request->length;
543         e->response.closure = request->closure;
544
545         if (request->data &&
546             copy_from_user(e->response.data,
547                            u64_to_uptr(request->data), request->length)) {
548                 ret = -EFAULT;
549                 goto failed;
550         }
551
552         e->r.resource.release = release_transaction;
553         ret = add_client_resource(client, &e->r.resource, GFP_KERNEL);
554         if (ret < 0)
555                 goto failed;
556
557         /* Get a reference for the transaction callback */
558         client_get(client);
559
560         fw_send_request(client->device->card, &e->r.transaction,
561                         request->tcode, destination_id, request->generation,
562                         speed, request->offset, e->response.data,
563                         request->length, complete_transaction, e);
564         return 0;
565
566  failed:
567         kfree(e);
568
569         return ret;
570 }
571
572 static int ioctl_send_request(struct client *client, void *buffer)
573 {
574         struct fw_cdev_send_request *request = buffer;
575
576         switch (request->tcode) {
577         case TCODE_WRITE_QUADLET_REQUEST:
578         case TCODE_WRITE_BLOCK_REQUEST:
579         case TCODE_READ_QUADLET_REQUEST:
580         case TCODE_READ_BLOCK_REQUEST:
581         case TCODE_LOCK_MASK_SWAP:
582         case TCODE_LOCK_COMPARE_SWAP:
583         case TCODE_LOCK_FETCH_ADD:
584         case TCODE_LOCK_LITTLE_ADD:
585         case TCODE_LOCK_BOUNDED_ADD:
586         case TCODE_LOCK_WRAP_ADD:
587         case TCODE_LOCK_VENDOR_DEPENDENT:
588                 break;
589         default:
590                 return -EINVAL;
591         }
592
593         return init_request(client, request, client->device->node_id,
594                             client->device->max_speed);
595 }
596
597 static void release_request(struct client *client,
598                             struct client_resource *resource)
599 {
600         struct inbound_transaction_resource *r = container_of(resource,
601                         struct inbound_transaction_resource, resource);
602
603         fw_send_response(client->device->card, r->request,
604                          RCODE_CONFLICT_ERROR);
605         kfree(r);
606 }
607
608 static void handle_request(struct fw_card *card, struct fw_request *request,
609                            int tcode, int destination, int source,
610                            int generation, int speed,
611                            unsigned long long offset,
612                            void *payload, size_t length, void *callback_data)
613 {
614         struct address_handler_resource *handler = callback_data;
615         struct inbound_transaction_resource *r;
616         struct inbound_transaction_event *e;
617         int ret;
618
619         r = kmalloc(sizeof(*r), GFP_ATOMIC);
620         e = kmalloc(sizeof(*e), GFP_ATOMIC);
621         if (r == NULL || e == NULL)
622                 goto failed;
623
624         r->request = request;
625         r->data    = payload;
626         r->length  = length;
627
628         r->resource.release = release_request;
629         ret = add_client_resource(handler->client, &r->resource, GFP_ATOMIC);
630         if (ret < 0)
631                 goto failed;
632
633         e->request.type    = FW_CDEV_EVENT_REQUEST;
634         e->request.tcode   = tcode;
635         e->request.offset  = offset;
636         e->request.length  = length;
637         e->request.handle  = r->resource.handle;
638         e->request.closure = handler->closure;
639
640         queue_event(handler->client, &e->event,
641                     &e->request, sizeof(e->request), payload, length);
642         return;
643
644  failed:
645         kfree(r);
646         kfree(e);
647         fw_send_response(card, request, RCODE_CONFLICT_ERROR);
648 }
649
650 static void release_address_handler(struct client *client,
651                                     struct client_resource *resource)
652 {
653         struct address_handler_resource *r =
654             container_of(resource, struct address_handler_resource, resource);
655
656         fw_core_remove_address_handler(&r->handler);
657         kfree(r);
658 }
659
660 static int ioctl_allocate(struct client *client, void *buffer)
661 {
662         struct fw_cdev_allocate *request = buffer;
663         struct address_handler_resource *r;
664         struct fw_address_region region;
665         int ret;
666
667         r = kmalloc(sizeof(*r), GFP_KERNEL);
668         if (r == NULL)
669                 return -ENOMEM;
670
671         region.start = request->offset;
672         region.end = request->offset + request->length;
673         r->handler.length = request->length;
674         r->handler.address_callback = handle_request;
675         r->handler.callback_data = r;
676         r->closure = request->closure;
677         r->client = client;
678
679         ret = fw_core_add_address_handler(&r->handler, &region);
680         if (ret < 0) {
681                 kfree(r);
682                 return ret;
683         }
684
685         r->resource.release = release_address_handler;
686         ret = add_client_resource(client, &r->resource, GFP_KERNEL);
687         if (ret < 0) {
688                 release_address_handler(client, &r->resource);
689                 return ret;
690         }
691         request->handle = r->resource.handle;
692
693         return 0;
694 }
695
696 static int ioctl_deallocate(struct client *client, void *buffer)
697 {
698         struct fw_cdev_deallocate *request = buffer;
699
700         return release_client_resource(client, request->handle,
701                                        release_address_handler, NULL);
702 }
703
704 static int ioctl_send_response(struct client *client, void *buffer)
705 {
706         struct fw_cdev_send_response *request = buffer;
707         struct client_resource *resource;
708         struct inbound_transaction_resource *r;
709         int ret = 0;
710
711         if (release_client_resource(client, request->handle,
712                                     release_request, &resource) < 0)
713                 return -EINVAL;
714
715         r = container_of(resource, struct inbound_transaction_resource,
716                          resource);
717         if (request->length < r->length)
718                 r->length = request->length;
719
720         if (copy_from_user(r->data, u64_to_uptr(request->data), r->length)) {
721                 ret = -EFAULT;
722                 goto out;
723         }
724
725         fw_send_response(client->device->card, r->request, request->rcode);
726  out:
727         kfree(r);
728
729         return ret;
730 }
731
732 static int ioctl_initiate_bus_reset(struct client *client, void *buffer)
733 {
734         struct fw_cdev_initiate_bus_reset *request = buffer;
735         int short_reset;
736
737         short_reset = (request->type == FW_CDEV_SHORT_RESET);
738
739         return fw_core_initiate_bus_reset(client->device->card, short_reset);
740 }
741
742 static void release_descriptor(struct client *client,
743                                struct client_resource *resource)
744 {
745         struct descriptor_resource *r =
746                 container_of(resource, struct descriptor_resource, resource);
747
748         fw_core_remove_descriptor(&r->descriptor);
749         kfree(r);
750 }
751
752 static int ioctl_add_descriptor(struct client *client, void *buffer)
753 {
754         struct fw_cdev_add_descriptor *request = buffer;
755         struct descriptor_resource *r;
756         int ret;
757
758         /* Access policy: Allow this ioctl only on local nodes' device files. */
759         if (!client->device->is_local)
760                 return -ENOSYS;
761
762         if (request->length > 256)
763                 return -EINVAL;
764
765         r = kmalloc(sizeof(*r) + request->length * 4, GFP_KERNEL);
766         if (r == NULL)
767                 return -ENOMEM;
768
769         if (copy_from_user(r->data,
770                            u64_to_uptr(request->data), request->length * 4)) {
771                 ret = -EFAULT;
772                 goto failed;
773         }
774
775         r->descriptor.length    = request->length;
776         r->descriptor.immediate = request->immediate;
777         r->descriptor.key       = request->key;
778         r->descriptor.data      = r->data;
779
780         ret = fw_core_add_descriptor(&r->descriptor);
781         if (ret < 0)
782                 goto failed;
783
784         r->resource.release = release_descriptor;
785         ret = add_client_resource(client, &r->resource, GFP_KERNEL);
786         if (ret < 0) {
787                 fw_core_remove_descriptor(&r->descriptor);
788                 goto failed;
789         }
790         request->handle = r->resource.handle;
791
792         return 0;
793  failed:
794         kfree(r);
795
796         return ret;
797 }
798
799 static int ioctl_remove_descriptor(struct client *client, void *buffer)
800 {
801         struct fw_cdev_remove_descriptor *request = buffer;
802
803         return release_client_resource(client, request->handle,
804                                        release_descriptor, NULL);
805 }
806
807 static void iso_callback(struct fw_iso_context *context, u32 cycle,
808                          size_t header_length, void *header, void *data)
809 {
810         struct client *client = data;
811         struct iso_interrupt_event *e;
812
813         e = kzalloc(sizeof(*e) + header_length, GFP_ATOMIC);
814         if (e == NULL)
815                 return;
816
817         e->interrupt.type      = FW_CDEV_EVENT_ISO_INTERRUPT;
818         e->interrupt.closure   = client->iso_closure;
819         e->interrupt.cycle     = cycle;
820         e->interrupt.header_length = header_length;
821         memcpy(e->interrupt.header, header, header_length);
822         queue_event(client, &e->event, &e->interrupt,
823                     sizeof(e->interrupt) + header_length, NULL, 0);
824 }
825
826 static int ioctl_create_iso_context(struct client *client, void *buffer)
827 {
828         struct fw_cdev_create_iso_context *request = buffer;
829         struct fw_iso_context *context;
830
831         /* We only support one context at this time. */
832         if (client->iso_context != NULL)
833                 return -EBUSY;
834
835         if (request->channel > 63)
836                 return -EINVAL;
837
838         switch (request->type) {
839         case FW_ISO_CONTEXT_RECEIVE:
840                 if (request->header_size < 4 || (request->header_size & 3))
841                         return -EINVAL;
842
843                 break;
844
845         case FW_ISO_CONTEXT_TRANSMIT:
846                 if (request->speed > SCODE_3200)
847                         return -EINVAL;
848
849                 break;
850
851         default:
852                 return -EINVAL;
853         }
854
855         context =  fw_iso_context_create(client->device->card,
856                                          request->type,
857                                          request->channel,
858                                          request->speed,
859                                          request->header_size,
860                                          iso_callback, client);
861         if (IS_ERR(context))
862                 return PTR_ERR(context);
863
864         client->iso_closure = request->closure;
865         client->iso_context = context;
866
867         /* We only support one context at this time. */
868         request->handle = 0;
869
870         return 0;
871 }
872
873 /* Macros for decoding the iso packet control header. */
874 #define GET_PAYLOAD_LENGTH(v)   ((v) & 0xffff)
875 #define GET_INTERRUPT(v)        (((v) >> 16) & 0x01)
876 #define GET_SKIP(v)             (((v) >> 17) & 0x01)
877 #define GET_TAG(v)              (((v) >> 18) & 0x03)
878 #define GET_SY(v)               (((v) >> 20) & 0x0f)
879 #define GET_HEADER_LENGTH(v)    (((v) >> 24) & 0xff)
880
881 static int ioctl_queue_iso(struct client *client, void *buffer)
882 {
883         struct fw_cdev_queue_iso *request = buffer;
884         struct fw_cdev_iso_packet __user *p, *end, *next;
885         struct fw_iso_context *ctx = client->iso_context;
886         unsigned long payload, buffer_end, header_length;
887         u32 control;
888         int count;
889         struct {
890                 struct fw_iso_packet packet;
891                 u8 header[256];
892         } u;
893
894         if (ctx == NULL || request->handle != 0)
895                 return -EINVAL;
896
897         /*
898          * If the user passes a non-NULL data pointer, has mmap()'ed
899          * the iso buffer, and the pointer points inside the buffer,
900          * we setup the payload pointers accordingly.  Otherwise we
901          * set them both to 0, which will still let packets with
902          * payload_length == 0 through.  In other words, if no packets
903          * use the indirect payload, the iso buffer need not be mapped
904          * and the request->data pointer is ignored.
905          */
906
907         payload = (unsigned long)request->data - client->vm_start;
908         buffer_end = client->buffer.page_count << PAGE_SHIFT;
909         if (request->data == 0 || client->buffer.pages == NULL ||
910             payload >= buffer_end) {
911                 payload = 0;
912                 buffer_end = 0;
913         }
914
915         p = (struct fw_cdev_iso_packet __user *)u64_to_uptr(request->packets);
916
917         if (!access_ok(VERIFY_READ, p, request->size))
918                 return -EFAULT;
919
920         end = (void __user *)p + request->size;
921         count = 0;
922         while (p < end) {
923                 if (get_user(control, &p->control))
924                         return -EFAULT;
925                 u.packet.payload_length = GET_PAYLOAD_LENGTH(control);
926                 u.packet.interrupt = GET_INTERRUPT(control);
927                 u.packet.skip = GET_SKIP(control);
928                 u.packet.tag = GET_TAG(control);
929                 u.packet.sy = GET_SY(control);
930                 u.packet.header_length = GET_HEADER_LENGTH(control);
931
932                 if (ctx->type == FW_ISO_CONTEXT_TRANSMIT) {
933                         header_length = u.packet.header_length;
934                 } else {
935                         /*
936                          * We require that header_length is a multiple of
937                          * the fixed header size, ctx->header_size.
938                          */
939                         if (ctx->header_size == 0) {
940                                 if (u.packet.header_length > 0)
941                                         return -EINVAL;
942                         } else if (u.packet.header_length % ctx->header_size != 0) {
943                                 return -EINVAL;
944                         }
945                         header_length = 0;
946                 }
947
948                 next = (struct fw_cdev_iso_packet __user *)
949                         &p->header[header_length / 4];
950                 if (next > end)
951                         return -EINVAL;
952                 if (__copy_from_user
953                     (u.packet.header, p->header, header_length))
954                         return -EFAULT;
955                 if (u.packet.skip && ctx->type == FW_ISO_CONTEXT_TRANSMIT &&
956                     u.packet.header_length + u.packet.payload_length > 0)
957                         return -EINVAL;
958                 if (payload + u.packet.payload_length > buffer_end)
959                         return -EINVAL;
960
961                 if (fw_iso_context_queue(ctx, &u.packet,
962                                          &client->buffer, payload))
963                         break;
964
965                 p = next;
966                 payload += u.packet.payload_length;
967                 count++;
968         }
969
970         request->size    -= uptr_to_u64(p) - request->packets;
971         request->packets  = uptr_to_u64(p);
972         request->data     = client->vm_start + payload;
973
974         return count;
975 }
976
977 static int ioctl_start_iso(struct client *client, void *buffer)
978 {
979         struct fw_cdev_start_iso *request = buffer;
980
981         if (client->iso_context == NULL || request->handle != 0)
982                 return -EINVAL;
983
984         if (client->iso_context->type == FW_ISO_CONTEXT_RECEIVE) {
985                 if (request->tags == 0 || request->tags > 15)
986                         return -EINVAL;
987
988                 if (request->sync > 15)
989                         return -EINVAL;
990         }
991
992         return fw_iso_context_start(client->iso_context, request->cycle,
993                                     request->sync, request->tags);
994 }
995
996 static int ioctl_stop_iso(struct client *client, void *buffer)
997 {
998         struct fw_cdev_stop_iso *request = buffer;
999
1000         if (client->iso_context == NULL || request->handle != 0)
1001                 return -EINVAL;
1002
1003         return fw_iso_context_stop(client->iso_context);
1004 }
1005
1006 static int ioctl_get_cycle_timer(struct client *client, void *buffer)
1007 {
1008         struct fw_cdev_get_cycle_timer *request = buffer;
1009         struct fw_card *card = client->device->card;
1010         unsigned long long bus_time;
1011         struct timeval tv;
1012         unsigned long flags;
1013
1014         preempt_disable();
1015         local_irq_save(flags);
1016
1017         bus_time = card->driver->get_bus_time(card);
1018         do_gettimeofday(&tv);
1019
1020         local_irq_restore(flags);
1021         preempt_enable();
1022
1023         request->local_time = tv.tv_sec * 1000000ULL + tv.tv_usec;
1024         request->cycle_timer = bus_time & 0xffffffff;
1025         return 0;
1026 }
1027
1028 static void iso_resource_work(struct work_struct *work)
1029 {
1030         struct iso_resource_event *e;
1031         struct iso_resource *r =
1032                         container_of(work, struct iso_resource, work.work);
1033         struct client *client = r->client;
1034         int generation, channel, bandwidth, todo;
1035         bool skip, free, success;
1036
1037         spin_lock_irq(&client->lock);
1038         generation = client->device->generation;
1039         todo = r->todo;
1040         /* Allow 1000ms grace period for other reallocations. */
1041         if (todo == ISO_RES_ALLOC &&
1042             time_is_after_jiffies(client->device->card->reset_jiffies + HZ)) {
1043                 schedule_iso_resource(r, DIV_ROUND_UP(HZ, 3));
1044                 skip = true;
1045         } else {
1046                 /* We could be called twice within the same generation. */
1047                 skip = todo == ISO_RES_REALLOC &&
1048                        r->generation == generation;
1049         }
1050         free = todo == ISO_RES_DEALLOC ||
1051                todo == ISO_RES_ALLOC_ONCE ||
1052                todo == ISO_RES_DEALLOC_ONCE;
1053         r->generation = generation;
1054         spin_unlock_irq(&client->lock);
1055
1056         if (skip)
1057                 goto out;
1058
1059         bandwidth = r->bandwidth;
1060
1061         fw_iso_resource_manage(client->device->card, generation,
1062                         r->channels, &channel, &bandwidth,
1063                         todo == ISO_RES_ALLOC ||
1064                         todo == ISO_RES_REALLOC ||
1065                         todo == ISO_RES_ALLOC_ONCE,
1066                         r->transaction_data);
1067         /*
1068          * Is this generation outdated already?  As long as this resource sticks
1069          * in the idr, it will be scheduled again for a newer generation or at
1070          * shutdown.
1071          */
1072         if (channel == -EAGAIN &&
1073             (todo == ISO_RES_ALLOC || todo == ISO_RES_REALLOC))
1074                 goto out;
1075
1076         success = channel >= 0 || bandwidth > 0;
1077
1078         spin_lock_irq(&client->lock);
1079         /*
1080          * Transit from allocation to reallocation, except if the client
1081          * requested deallocation in the meantime.
1082          */
1083         if (r->todo == ISO_RES_ALLOC)
1084                 r->todo = ISO_RES_REALLOC;
1085         /*
1086          * Allocation or reallocation failure?  Pull this resource out of the
1087          * idr and prepare for deletion, unless the client is shutting down.
1088          */
1089         if (r->todo == ISO_RES_REALLOC && !success &&
1090             !client->in_shutdown &&
1091             idr_find(&client->resource_idr, r->resource.handle)) {
1092                 idr_remove(&client->resource_idr, r->resource.handle);
1093                 client_put(client);
1094                 free = true;
1095         }
1096         spin_unlock_irq(&client->lock);
1097
1098         if (todo == ISO_RES_ALLOC && channel >= 0)
1099                 r->channels = 1ULL << channel;
1100
1101         if (todo == ISO_RES_REALLOC && success)
1102                 goto out;
1103
1104         if (todo == ISO_RES_ALLOC || todo == ISO_RES_ALLOC_ONCE) {
1105                 e = r->e_alloc;
1106                 r->e_alloc = NULL;
1107         } else {
1108                 e = r->e_dealloc;
1109                 r->e_dealloc = NULL;
1110         }
1111         e->iso_resource.handle    = r->resource.handle;
1112         e->iso_resource.channel   = channel;
1113         e->iso_resource.bandwidth = bandwidth;
1114
1115         queue_event(client, &e->event,
1116                     &e->iso_resource, sizeof(e->iso_resource), NULL, 0);
1117
1118         if (free) {
1119                 cancel_delayed_work(&r->work);
1120                 kfree(r->e_alloc);
1121                 kfree(r->e_dealloc);
1122                 kfree(r);
1123         }
1124  out:
1125         client_put(client);
1126 }
1127
1128 static void release_iso_resource(struct client *client,
1129                                  struct client_resource *resource)
1130 {
1131         struct iso_resource *r =
1132                 container_of(resource, struct iso_resource, resource);
1133
1134         spin_lock_irq(&client->lock);
1135         r->todo = ISO_RES_DEALLOC;
1136         schedule_iso_resource(r, 0);
1137         spin_unlock_irq(&client->lock);
1138 }
1139
1140 static int init_iso_resource(struct client *client,
1141                 struct fw_cdev_allocate_iso_resource *request, int todo)
1142 {
1143         struct iso_resource_event *e1, *e2;
1144         struct iso_resource *r;
1145         int ret;
1146
1147         if ((request->channels == 0 && request->bandwidth == 0) ||
1148             request->bandwidth > BANDWIDTH_AVAILABLE_INITIAL ||
1149             request->bandwidth < 0)
1150                 return -EINVAL;
1151
1152         r  = kmalloc(sizeof(*r), GFP_KERNEL);
1153         e1 = kmalloc(sizeof(*e1), GFP_KERNEL);
1154         e2 = kmalloc(sizeof(*e2), GFP_KERNEL);
1155         if (r == NULL || e1 == NULL || e2 == NULL) {
1156                 ret = -ENOMEM;
1157                 goto fail;
1158         }
1159
1160         INIT_DELAYED_WORK(&r->work, iso_resource_work);
1161         r->client       = client;
1162         r->todo         = todo;
1163         r->generation   = -1;
1164         r->channels     = request->channels;
1165         r->bandwidth    = request->bandwidth;
1166         r->e_alloc      = e1;
1167         r->e_dealloc    = e2;
1168
1169         e1->iso_resource.closure = request->closure;
1170         e1->iso_resource.type    = FW_CDEV_EVENT_ISO_RESOURCE_ALLOCATED;
1171         e2->iso_resource.closure = request->closure;
1172         e2->iso_resource.type    = FW_CDEV_EVENT_ISO_RESOURCE_DEALLOCATED;
1173
1174         if (todo == ISO_RES_ALLOC) {
1175                 r->resource.release = release_iso_resource;
1176                 ret = add_client_resource(client, &r->resource, GFP_KERNEL);
1177                 if (ret < 0)
1178                         goto fail;
1179         } else {
1180                 r->resource.release = NULL;
1181                 r->resource.handle = -1;
1182                 schedule_iso_resource(r, 0);
1183         }
1184         request->handle = r->resource.handle;
1185
1186         return 0;
1187  fail:
1188         kfree(r);
1189         kfree(e1);
1190         kfree(e2);
1191
1192         return ret;
1193 }
1194
1195 static int ioctl_allocate_iso_resource(struct client *client, void *buffer)
1196 {
1197         struct fw_cdev_allocate_iso_resource *request = buffer;
1198
1199         return init_iso_resource(client, request, ISO_RES_ALLOC);
1200 }
1201
1202 static int ioctl_deallocate_iso_resource(struct client *client, void *buffer)
1203 {
1204         struct fw_cdev_deallocate *request = buffer;
1205
1206         return release_client_resource(client, request->handle,
1207                                        release_iso_resource, NULL);
1208 }
1209
1210 static int ioctl_allocate_iso_resource_once(struct client *client, void *buffer)
1211 {
1212         struct fw_cdev_allocate_iso_resource *request = buffer;
1213
1214         return init_iso_resource(client, request, ISO_RES_ALLOC_ONCE);
1215 }
1216
1217 static int ioctl_deallocate_iso_resource_once(struct client *client, void *buffer)
1218 {
1219         struct fw_cdev_allocate_iso_resource *request = buffer;
1220
1221         return init_iso_resource(client, request, ISO_RES_DEALLOC_ONCE);
1222 }
1223
1224 /*
1225  * Returns a speed code:  Maximum speed to or from this device,
1226  * limited by the device's link speed, the local node's link speed,
1227  * and all PHY port speeds between the two links.
1228  */
1229 static int ioctl_get_speed(struct client *client, void *buffer)
1230 {
1231         return client->device->max_speed;
1232 }
1233
1234 static int ioctl_send_broadcast_request(struct client *client, void *buffer)
1235 {
1236         struct fw_cdev_send_request *request = buffer;
1237
1238         switch (request->tcode) {
1239         case TCODE_WRITE_QUADLET_REQUEST:
1240         case TCODE_WRITE_BLOCK_REQUEST:
1241                 break;
1242         default:
1243                 return -EINVAL;
1244         }
1245
1246         /* Security policy: Only allow accesses to Units Space. */
1247         if (request->offset < CSR_REGISTER_BASE + CSR_CONFIG_ROM_END)
1248                 return -EACCES;
1249
1250         return init_request(client, request, LOCAL_BUS | 0x3f, SCODE_100);
1251 }
1252
1253 static int ioctl_send_stream_packet(struct client *client, void *buffer)
1254 {
1255         struct fw_cdev_send_stream_packet *p = buffer;
1256         struct fw_cdev_send_request request;
1257         int dest;
1258
1259         if (p->speed > client->device->card->link_speed ||
1260             p->length > 1024 << p->speed)
1261                 return -EIO;
1262
1263         if (p->tag > 3 || p->channel > 63 || p->sy > 15)
1264                 return -EINVAL;
1265
1266         dest = fw_stream_packet_destination_id(p->tag, p->channel, p->sy);
1267         request.tcode           = TCODE_STREAM_DATA;
1268         request.length          = p->length;
1269         request.closure         = p->closure;
1270         request.data            = p->data;
1271         request.generation      = p->generation;
1272
1273         return init_request(client, &request, dest, p->speed);
1274 }
1275
1276 static int (* const ioctl_handlers[])(struct client *client, void *buffer) = {
1277         ioctl_get_info,
1278         ioctl_send_request,
1279         ioctl_allocate,
1280         ioctl_deallocate,
1281         ioctl_send_response,
1282         ioctl_initiate_bus_reset,
1283         ioctl_add_descriptor,
1284         ioctl_remove_descriptor,
1285         ioctl_create_iso_context,
1286         ioctl_queue_iso,
1287         ioctl_start_iso,
1288         ioctl_stop_iso,
1289         ioctl_get_cycle_timer,
1290         ioctl_allocate_iso_resource,
1291         ioctl_deallocate_iso_resource,
1292         ioctl_allocate_iso_resource_once,
1293         ioctl_deallocate_iso_resource_once,
1294         ioctl_get_speed,
1295         ioctl_send_broadcast_request,
1296         ioctl_send_stream_packet,
1297 };
1298
1299 static int dispatch_ioctl(struct client *client,
1300                           unsigned int cmd, void __user *arg)
1301 {
1302         char buffer[sizeof(union {
1303                 struct fw_cdev_get_info                 _00;
1304                 struct fw_cdev_send_request             _01;
1305                 struct fw_cdev_allocate                 _02;
1306                 struct fw_cdev_deallocate               _03;
1307                 struct fw_cdev_send_response            _04;
1308                 struct fw_cdev_initiate_bus_reset       _05;
1309                 struct fw_cdev_add_descriptor           _06;
1310                 struct fw_cdev_remove_descriptor        _07;
1311                 struct fw_cdev_create_iso_context       _08;
1312                 struct fw_cdev_queue_iso                _09;
1313                 struct fw_cdev_start_iso                _0a;
1314                 struct fw_cdev_stop_iso                 _0b;
1315                 struct fw_cdev_get_cycle_timer          _0c;
1316                 struct fw_cdev_allocate_iso_resource    _0d;
1317                 struct fw_cdev_send_stream_packet       _13;
1318         })];
1319         int ret;
1320
1321         if (_IOC_TYPE(cmd) != '#' ||
1322             _IOC_NR(cmd) >= ARRAY_SIZE(ioctl_handlers))
1323                 return -EINVAL;
1324
1325         if (_IOC_DIR(cmd) & _IOC_WRITE) {
1326                 if (_IOC_SIZE(cmd) > sizeof(buffer) ||
1327                     copy_from_user(buffer, arg, _IOC_SIZE(cmd)))
1328                         return -EFAULT;
1329         }
1330
1331         ret = ioctl_handlers[_IOC_NR(cmd)](client, buffer);
1332         if (ret < 0)
1333                 return ret;
1334
1335         if (_IOC_DIR(cmd) & _IOC_READ) {
1336                 if (_IOC_SIZE(cmd) > sizeof(buffer) ||
1337                     copy_to_user(arg, buffer, _IOC_SIZE(cmd)))
1338                         return -EFAULT;
1339         }
1340
1341         return ret;
1342 }
1343
1344 static long fw_device_op_ioctl(struct file *file,
1345                                unsigned int cmd, unsigned long arg)
1346 {
1347         struct client *client = file->private_data;
1348
1349         if (fw_device_is_shutdown(client->device))
1350                 return -ENODEV;
1351
1352         return dispatch_ioctl(client, cmd, (void __user *) arg);
1353 }
1354
1355 #ifdef CONFIG_COMPAT
1356 static long fw_device_op_compat_ioctl(struct file *file,
1357                                       unsigned int cmd, unsigned long arg)
1358 {
1359         struct client *client = file->private_data;
1360
1361         if (fw_device_is_shutdown(client->device))
1362                 return -ENODEV;
1363
1364         return dispatch_ioctl(client, cmd, compat_ptr(arg));
1365 }
1366 #endif
1367
1368 static int fw_device_op_mmap(struct file *file, struct vm_area_struct *vma)
1369 {
1370         struct client *client = file->private_data;
1371         enum dma_data_direction direction;
1372         unsigned long size;
1373         int page_count, ret;
1374
1375         if (fw_device_is_shutdown(client->device))
1376                 return -ENODEV;
1377
1378         /* FIXME: We could support multiple buffers, but we don't. */
1379         if (client->buffer.pages != NULL)
1380                 return -EBUSY;
1381
1382         if (!(vma->vm_flags & VM_SHARED))
1383                 return -EINVAL;
1384
1385         if (vma->vm_start & ~PAGE_MASK)
1386                 return -EINVAL;
1387
1388         client->vm_start = vma->vm_start;
1389         size = vma->vm_end - vma->vm_start;
1390         page_count = size >> PAGE_SHIFT;
1391         if (size & ~PAGE_MASK)
1392                 return -EINVAL;
1393
1394         if (vma->vm_flags & VM_WRITE)
1395                 direction = DMA_TO_DEVICE;
1396         else
1397                 direction = DMA_FROM_DEVICE;
1398
1399         ret = fw_iso_buffer_init(&client->buffer, client->device->card,
1400                                  page_count, direction);
1401         if (ret < 0)
1402                 return ret;
1403
1404         ret = fw_iso_buffer_map(&client->buffer, vma);
1405         if (ret < 0)
1406                 fw_iso_buffer_destroy(&client->buffer, client->device->card);
1407
1408         return ret;
1409 }
1410
1411 static int shutdown_resource(int id, void *p, void *data)
1412 {
1413         struct client_resource *resource = p;
1414         struct client *client = data;
1415
1416         resource->release(client, resource);
1417         client_put(client);
1418
1419         return 0;
1420 }
1421
1422 static int fw_device_op_release(struct inode *inode, struct file *file)
1423 {
1424         struct client *client = file->private_data;
1425         struct event *event, *next_event;
1426
1427         mutex_lock(&client->device->client_list_mutex);
1428         list_del(&client->link);
1429         mutex_unlock(&client->device->client_list_mutex);
1430
1431         if (client->iso_context)
1432                 fw_iso_context_destroy(client->iso_context);
1433
1434         if (client->buffer.pages)
1435                 fw_iso_buffer_destroy(&client->buffer, client->device->card);
1436
1437         /* Freeze client->resource_idr and client->event_list */
1438         spin_lock_irq(&client->lock);
1439         client->in_shutdown = true;
1440         spin_unlock_irq(&client->lock);
1441
1442         idr_for_each(&client->resource_idr, shutdown_resource, client);
1443         idr_remove_all(&client->resource_idr);
1444         idr_destroy(&client->resource_idr);
1445
1446         list_for_each_entry_safe(event, next_event, &client->event_list, link)
1447                 kfree(event);
1448
1449         client_put(client);
1450
1451         return 0;
1452 }
1453
1454 static unsigned int fw_device_op_poll(struct file *file, poll_table * pt)
1455 {
1456         struct client *client = file->private_data;
1457         unsigned int mask = 0;
1458
1459         poll_wait(file, &client->wait, pt);
1460
1461         if (fw_device_is_shutdown(client->device))
1462                 mask |= POLLHUP | POLLERR;
1463         if (!list_empty(&client->event_list))
1464                 mask |= POLLIN | POLLRDNORM;
1465
1466         return mask;
1467 }
1468
1469 const struct file_operations fw_device_ops = {
1470         .owner          = THIS_MODULE,
1471         .open           = fw_device_op_open,
1472         .read           = fw_device_op_read,
1473         .unlocked_ioctl = fw_device_op_ioctl,
1474         .poll           = fw_device_op_poll,
1475         .release        = fw_device_op_release,
1476         .mmap           = fw_device_op_mmap,
1477
1478 #ifdef CONFIG_COMPAT
1479         .compat_ioctl   = fw_device_op_compat_ioctl,
1480 #endif
1481 };