xref: /linux/drivers/firewire/core-cdev.c (revision 07fdad3a93756b872da7b53647715c48d0f4a2d0)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Char device for device raw access
4  *
5  * Copyright (C) 2005-2007  Kristian Hoegsberg <krh@bitplanet.net>
6  */
7 
8 #include <linux/bug.h>
9 #include <linux/compat.h>
10 #include <linux/delay.h>
11 #include <linux/device.h>
12 #include <linux/dma-mapping.h>
13 #include <linux/err.h>
14 #include <linux/errno.h>
15 #include <linux/firewire.h>
16 #include <linux/firewire-cdev.h>
17 #include <linux/irqflags.h>
18 #include <linux/jiffies.h>
19 #include <linux/kernel.h>
20 #include <linux/kref.h>
21 #include <linux/mm.h>
22 #include <linux/module.h>
23 #include <linux/mutex.h>
24 #include <linux/poll.h>
25 #include <linux/sched.h> /* required for linux/wait.h */
26 #include <linux/slab.h>
27 #include <linux/spinlock.h>
28 #include <linux/string.h>
29 #include <linux/time.h>
30 #include <linux/uaccess.h>
31 #include <linux/vmalloc.h>
32 #include <linux/wait.h>
33 #include <linux/workqueue.h>
34 
35 
36 #include "core.h"
37 #include <trace/events/firewire.h>
38 
39 #include "packet-header-definitions.h"
40 
41 /*
42  * ABI version history is documented in linux/firewire-cdev.h.
43  */
44 #define FW_CDEV_KERNEL_VERSION			6
45 #define FW_CDEV_VERSION_EVENT_REQUEST2		4
46 #define FW_CDEV_VERSION_ALLOCATE_REGION_END	4
47 #define FW_CDEV_VERSION_AUTO_FLUSH_ISO_OVERFLOW	5
48 #define FW_CDEV_VERSION_EVENT_ASYNC_TSTAMP	6
49 
50 static DEFINE_SPINLOCK(phy_receiver_list_lock);
51 static LIST_HEAD(phy_receiver_list);
52 
53 struct client {
54 	u32 version;
55 	struct fw_device *device;
56 
57 	spinlock_t lock;
58 	bool in_shutdown;
59 	struct xarray resource_xa;
60 	struct list_head event_list;
61 	wait_queue_head_t wait;
62 	wait_queue_head_t tx_flush_wait;
63 	u64 bus_reset_closure;
64 
65 	struct fw_iso_context *iso_context;
66 	u64 iso_closure;
67 	struct fw_iso_buffer buffer;
68 	unsigned long vm_start;
69 	bool buffer_is_mapped;
70 
71 	struct list_head phy_receiver_link;
72 	u64 phy_receiver_closure;
73 
74 	struct list_head link;
75 	struct kref kref;
76 };
77 
78 static inline void client_get(struct client *client)
79 {
80 	kref_get(&client->kref);
81 }
82 
83 static void client_release(struct kref *kref)
84 {
85 	struct client *client = container_of(kref, struct client, kref);
86 
87 	fw_device_put(client->device);
88 	kfree(client);
89 }
90 
91 static void client_put(struct client *client)
92 {
93 	kref_put(&client->kref, client_release);
94 }
95 
96 struct client_resource;
97 typedef void (*client_resource_release_fn_t)(struct client *,
98 					     struct client_resource *);
99 struct client_resource {
100 	client_resource_release_fn_t release;
101 	int handle;
102 };
103 
104 struct address_handler_resource {
105 	struct client_resource resource;
106 	struct fw_address_handler handler;
107 	__u64 closure;
108 	struct client *client;
109 };
110 
111 struct outbound_transaction_resource {
112 	struct client_resource resource;
113 	struct fw_transaction transaction;
114 };
115 
116 struct inbound_transaction_resource {
117 	struct client_resource resource;
118 	struct fw_card *card;
119 	struct fw_request *request;
120 	bool is_fcp;
121 	void *data;
122 	size_t length;
123 };
124 
125 struct descriptor_resource {
126 	struct client_resource resource;
127 	struct fw_descriptor descriptor;
128 	u32 data[];
129 };
130 
131 struct iso_resource {
132 	struct client_resource resource;
133 	struct client *client;
134 	/* Schedule work and access todo only with client->lock held. */
135 	struct delayed_work work;
136 	enum {ISO_RES_ALLOC, ISO_RES_REALLOC, ISO_RES_DEALLOC,
137 	      ISO_RES_ALLOC_ONCE, ISO_RES_DEALLOC_ONCE,} todo;
138 	int generation;
139 	u64 channels;
140 	s32 bandwidth;
141 	struct iso_resource_event *e_alloc, *e_dealloc;
142 };
143 
144 static struct address_handler_resource *to_address_handler_resource(struct client_resource *resource)
145 {
146 	return container_of(resource, struct address_handler_resource, resource);
147 }
148 
149 static struct inbound_transaction_resource *to_inbound_transaction_resource(struct client_resource *resource)
150 {
151 	return container_of(resource, struct inbound_transaction_resource, resource);
152 }
153 
154 static struct descriptor_resource *to_descriptor_resource(struct client_resource *resource)
155 {
156 	return container_of(resource, struct descriptor_resource, resource);
157 }
158 
159 static struct iso_resource *to_iso_resource(struct client_resource *resource)
160 {
161 	return container_of(resource, struct iso_resource, resource);
162 }
163 
164 static void release_iso_resource(struct client *, struct client_resource *);
165 
166 static int is_iso_resource(const struct client_resource *resource)
167 {
168 	return resource->release == release_iso_resource;
169 }
170 
171 static void release_transaction(struct client *client,
172 				struct client_resource *resource);
173 
174 static int is_outbound_transaction_resource(const struct client_resource *resource)
175 {
176 	return resource->release == release_transaction;
177 }
178 
179 static void schedule_iso_resource(struct iso_resource *r, unsigned long delay)
180 {
181 	client_get(r->client);
182 	if (!queue_delayed_work(fw_workqueue, &r->work, delay))
183 		client_put(r->client);
184 }
185 
186 /*
187  * dequeue_event() just kfree()'s the event, so the event has to be
188  * the first field in a struct XYZ_event.
189  */
190 struct event {
191 	struct { void *data; size_t size; } v[2];
192 	struct list_head link;
193 };
194 
195 struct bus_reset_event {
196 	struct event event;
197 	struct fw_cdev_event_bus_reset reset;
198 };
199 
200 struct outbound_transaction_event {
201 	struct event event;
202 	struct client *client;
203 	struct outbound_transaction_resource r;
204 	union {
205 		struct fw_cdev_event_response without_tstamp;
206 		struct fw_cdev_event_response2 with_tstamp;
207 	} rsp;
208 };
209 
210 struct inbound_transaction_event {
211 	struct event event;
212 	union {
213 		struct fw_cdev_event_request request;
214 		struct fw_cdev_event_request2 request2;
215 		struct fw_cdev_event_request3 with_tstamp;
216 	} req;
217 };
218 
219 struct iso_interrupt_event {
220 	struct event event;
221 	struct fw_cdev_event_iso_interrupt interrupt;
222 };
223 
224 struct iso_interrupt_mc_event {
225 	struct event event;
226 	struct fw_cdev_event_iso_interrupt_mc interrupt;
227 };
228 
229 struct iso_resource_event {
230 	struct event event;
231 	struct fw_cdev_event_iso_resource iso_resource;
232 };
233 
234 struct outbound_phy_packet_event {
235 	struct event event;
236 	struct client *client;
237 	struct fw_packet p;
238 	union {
239 		struct fw_cdev_event_phy_packet without_tstamp;
240 		struct fw_cdev_event_phy_packet2 with_tstamp;
241 	} phy_packet;
242 };
243 
244 struct inbound_phy_packet_event {
245 	struct event event;
246 	union {
247 		struct fw_cdev_event_phy_packet without_tstamp;
248 		struct fw_cdev_event_phy_packet2 with_tstamp;
249 	} phy_packet;
250 };
251 
252 #ifdef CONFIG_COMPAT
253 static void __user *u64_to_uptr(u64 value)
254 {
255 	if (in_compat_syscall())
256 		return compat_ptr(value);
257 	else
258 		return (void __user *)(unsigned long)value;
259 }
260 
261 static u64 uptr_to_u64(void __user *ptr)
262 {
263 	if (in_compat_syscall())
264 		return ptr_to_compat(ptr);
265 	else
266 		return (u64)(unsigned long)ptr;
267 }
268 #else
269 static inline void __user *u64_to_uptr(u64 value)
270 {
271 	return (void __user *)(unsigned long)value;
272 }
273 
274 static inline u64 uptr_to_u64(void __user *ptr)
275 {
276 	return (u64)(unsigned long)ptr;
277 }
278 #endif /* CONFIG_COMPAT */
279 
280 static int fw_device_op_open(struct inode *inode, struct file *file)
281 {
282 	struct fw_device *device;
283 	struct client *client;
284 
285 	device = fw_device_get_by_devt(inode->i_rdev);
286 	if (device == NULL)
287 		return -ENODEV;
288 
289 	if (fw_device_is_shutdown(device)) {
290 		fw_device_put(device);
291 		return -ENODEV;
292 	}
293 
294 	client = kzalloc(sizeof(*client), GFP_KERNEL);
295 	if (client == NULL) {
296 		fw_device_put(device);
297 		return -ENOMEM;
298 	}
299 
300 	client->device = device;
301 	spin_lock_init(&client->lock);
302 	xa_init_flags(&client->resource_xa, XA_FLAGS_ALLOC1 | XA_FLAGS_LOCK_BH);
303 	INIT_LIST_HEAD(&client->event_list);
304 	init_waitqueue_head(&client->wait);
305 	init_waitqueue_head(&client->tx_flush_wait);
306 	INIT_LIST_HEAD(&client->phy_receiver_link);
307 	INIT_LIST_HEAD(&client->link);
308 	kref_init(&client->kref);
309 
310 	file->private_data = client;
311 
312 	return nonseekable_open(inode, file);
313 }
314 
315 static void queue_event(struct client *client, struct event *event,
316 			void *data0, size_t size0, void *data1, size_t size1)
317 {
318 	event->v[0].data = data0;
319 	event->v[0].size = size0;
320 	event->v[1].data = data1;
321 	event->v[1].size = size1;
322 
323 	scoped_guard(spinlock_irqsave, &client->lock) {
324 		if (client->in_shutdown)
325 			kfree(event);
326 		else
327 			list_add_tail(&event->link, &client->event_list);
328 	}
329 
330 	wake_up_interruptible(&client->wait);
331 }
332 
333 static int dequeue_event(struct client *client,
334 			 char __user *buffer, size_t count)
335 {
336 	struct event *event;
337 	size_t size, total;
338 	int i, ret;
339 
340 	ret = wait_event_interruptible(client->wait,
341 			!list_empty(&client->event_list) ||
342 			fw_device_is_shutdown(client->device));
343 	if (ret < 0)
344 		return ret;
345 
346 	if (list_empty(&client->event_list) &&
347 		       fw_device_is_shutdown(client->device))
348 		return -ENODEV;
349 
350 	scoped_guard(spinlock_irq, &client->lock) {
351 		event = list_first_entry(&client->event_list, struct event, link);
352 		list_del(&event->link);
353 	}
354 
355 	total = 0;
356 	for (i = 0; i < ARRAY_SIZE(event->v) && total < count; i++) {
357 		size = min(event->v[i].size, count - total);
358 		if (copy_to_user(buffer + total, event->v[i].data, size)) {
359 			ret = -EFAULT;
360 			goto out;
361 		}
362 		total += size;
363 	}
364 	ret = total;
365 
366  out:
367 	kfree(event);
368 
369 	return ret;
370 }
371 
372 static ssize_t fw_device_op_read(struct file *file, char __user *buffer,
373 				 size_t count, loff_t *offset)
374 {
375 	struct client *client = file->private_data;
376 
377 	return dequeue_event(client, buffer, count);
378 }
379 
380 static void fill_bus_reset_event(struct fw_cdev_event_bus_reset *event,
381 				 struct client *client)
382 {
383 	struct fw_card *card = client->device->card;
384 
385 	guard(spinlock_irq)(&card->lock);
386 
387 	event->closure	     = client->bus_reset_closure;
388 	event->type          = FW_CDEV_EVENT_BUS_RESET;
389 	event->generation    = client->device->generation;
390 	event->node_id       = client->device->node_id;
391 	event->local_node_id = card->local_node->node_id;
392 	event->bm_node_id    = card->bm_node_id;
393 	event->irm_node_id   = card->irm_node->node_id;
394 	event->root_node_id  = card->root_node->node_id;
395 }
396 
397 static void for_each_client(struct fw_device *device,
398 			    void (*callback)(struct client *client))
399 {
400 	struct client *c;
401 
402 	guard(mutex)(&device->client_list_mutex);
403 
404 	list_for_each_entry(c, &device->client_list, link)
405 		callback(c);
406 }
407 
408 static void queue_bus_reset_event(struct client *client)
409 {
410 	struct bus_reset_event *e;
411 	struct client_resource *resource;
412 	unsigned long index;
413 
414 	e = kzalloc(sizeof(*e), GFP_KERNEL);
415 	if (e == NULL)
416 		return;
417 
418 	fill_bus_reset_event(&e->reset, client);
419 
420 	queue_event(client, &e->event,
421 		    &e->reset, sizeof(e->reset), NULL, 0);
422 
423 	guard(spinlock_irq)(&client->lock);
424 
425 	xa_for_each(&client->resource_xa, index, resource) {
426 		if (is_iso_resource(resource))
427 			schedule_iso_resource(to_iso_resource(resource), 0);
428 	}
429 }
430 
431 void fw_device_cdev_update(struct fw_device *device)
432 {
433 	for_each_client(device, queue_bus_reset_event);
434 }
435 
436 static void wake_up_client(struct client *client)
437 {
438 	wake_up_interruptible(&client->wait);
439 }
440 
441 void fw_device_cdev_remove(struct fw_device *device)
442 {
443 	for_each_client(device, wake_up_client);
444 }
445 
446 union ioctl_arg {
447 	struct fw_cdev_get_info			get_info;
448 	struct fw_cdev_send_request		send_request;
449 	struct fw_cdev_allocate			allocate;
450 	struct fw_cdev_deallocate		deallocate;
451 	struct fw_cdev_send_response		send_response;
452 	struct fw_cdev_initiate_bus_reset	initiate_bus_reset;
453 	struct fw_cdev_add_descriptor		add_descriptor;
454 	struct fw_cdev_remove_descriptor	remove_descriptor;
455 	struct fw_cdev_create_iso_context	create_iso_context;
456 	struct fw_cdev_queue_iso		queue_iso;
457 	struct fw_cdev_start_iso		start_iso;
458 	struct fw_cdev_stop_iso			stop_iso;
459 	struct fw_cdev_get_cycle_timer		get_cycle_timer;
460 	struct fw_cdev_allocate_iso_resource	allocate_iso_resource;
461 	struct fw_cdev_send_stream_packet	send_stream_packet;
462 	struct fw_cdev_get_cycle_timer2		get_cycle_timer2;
463 	struct fw_cdev_send_phy_packet		send_phy_packet;
464 	struct fw_cdev_receive_phy_packets	receive_phy_packets;
465 	struct fw_cdev_set_iso_channels		set_iso_channels;
466 	struct fw_cdev_flush_iso		flush_iso;
467 };
468 
469 static int ioctl_get_info(struct client *client, union ioctl_arg *arg)
470 {
471 	struct fw_cdev_get_info *a = &arg->get_info;
472 	struct fw_cdev_event_bus_reset bus_reset;
473 	unsigned long ret = 0;
474 
475 	client->version = a->version;
476 	a->version = FW_CDEV_KERNEL_VERSION;
477 	a->card = client->device->card->index;
478 
479 	scoped_guard(rwsem_read, &fw_device_rwsem) {
480 		if (a->rom != 0) {
481 			size_t want = a->rom_length;
482 			size_t have = client->device->config_rom_length * 4;
483 
484 			ret = copy_to_user(u64_to_uptr(a->rom), client->device->config_rom,
485 					   min(want, have));
486 			if (ret != 0)
487 				return -EFAULT;
488 		}
489 		a->rom_length = client->device->config_rom_length * 4;
490 	}
491 
492 	guard(mutex)(&client->device->client_list_mutex);
493 
494 	client->bus_reset_closure = a->bus_reset_closure;
495 	if (a->bus_reset != 0) {
496 		fill_bus_reset_event(&bus_reset, client);
497 		/* unaligned size of bus_reset is 36 bytes */
498 		ret = copy_to_user(u64_to_uptr(a->bus_reset), &bus_reset, 36);
499 	}
500 	if (ret == 0 && list_empty(&client->link))
501 		list_add_tail(&client->link, &client->device->client_list);
502 
503 	return ret ? -EFAULT : 0;
504 }
505 
506 static int add_client_resource(struct client *client, struct client_resource *resource,
507 			       gfp_t gfp_mask)
508 {
509 	int ret;
510 
511 	scoped_guard(spinlock_irqsave, &client->lock) {
512 		u32 index;
513 
514 		if (client->in_shutdown) {
515 			ret = -ECANCELED;
516 		} else {
517 			if (gfpflags_allow_blocking(gfp_mask)) {
518 				ret = xa_alloc(&client->resource_xa, &index, resource, xa_limit_32b,
519 					       GFP_NOWAIT);
520 			} else {
521 				ret = xa_alloc_bh(&client->resource_xa, &index, resource,
522 						  xa_limit_32b, GFP_NOWAIT);
523 			}
524 		}
525 		if (ret >= 0) {
526 			resource->handle = index;
527 			client_get(client);
528 			if (is_iso_resource(resource))
529 				schedule_iso_resource(to_iso_resource(resource), 0);
530 		}
531 	}
532 
533 	return ret < 0 ? ret : 0;
534 }
535 
536 static int release_client_resource(struct client *client, u32 handle,
537 				   client_resource_release_fn_t release,
538 				   struct client_resource **return_resource)
539 {
540 	unsigned long index = handle;
541 	struct client_resource *resource;
542 
543 	scoped_guard(spinlock_irq, &client->lock) {
544 		if (client->in_shutdown)
545 			return -EINVAL;
546 
547 		resource = xa_load(&client->resource_xa, index);
548 		if (!resource || resource->release != release)
549 			return -EINVAL;
550 
551 		xa_erase(&client->resource_xa, handle);
552 	}
553 
554 	if (return_resource)
555 		*return_resource = resource;
556 	else
557 		resource->release(client, resource);
558 
559 	client_put(client);
560 
561 	return 0;
562 }
563 
564 static void release_transaction(struct client *client,
565 				struct client_resource *resource)
566 {
567 }
568 
569 static void complete_transaction(struct fw_card *card, int rcode, u32 request_tstamp,
570 				 u32 response_tstamp, void *payload, size_t length, void *data)
571 {
572 	struct outbound_transaction_event *e = data;
573 	struct client *client = e->client;
574 	unsigned long index = e->r.resource.handle;
575 
576 	scoped_guard(spinlock_irqsave, &client->lock) {
577 		xa_erase(&client->resource_xa, index);
578 		if (client->in_shutdown)
579 			wake_up(&client->tx_flush_wait);
580 	}
581 
582 	switch (e->rsp.without_tstamp.type) {
583 	case FW_CDEV_EVENT_RESPONSE:
584 	{
585 		struct fw_cdev_event_response *rsp = &e->rsp.without_tstamp;
586 
587 		if (length < rsp->length)
588 			rsp->length = length;
589 		if (rcode == RCODE_COMPLETE)
590 			memcpy(rsp->data, payload, rsp->length);
591 
592 		rsp->rcode = rcode;
593 
594 		// In the case that sizeof(*rsp) doesn't align with the position of the
595 		// data, and the read is short, preserve an extra copy of the data
596 		// to stay compatible with a pre-2.6.27 bug.  Since the bug is harmless
597 		// for short reads and some apps depended on it, this is both safe
598 		// and prudent for compatibility.
599 		if (rsp->length <= sizeof(*rsp) - offsetof(typeof(*rsp), data))
600 			queue_event(client, &e->event, rsp, sizeof(*rsp), rsp->data, rsp->length);
601 		else
602 			queue_event(client, &e->event, rsp, sizeof(*rsp) + rsp->length, NULL, 0);
603 
604 		break;
605 	}
606 	case FW_CDEV_EVENT_RESPONSE2:
607 	{
608 		struct fw_cdev_event_response2 *rsp = &e->rsp.with_tstamp;
609 
610 		if (length < rsp->length)
611 			rsp->length = length;
612 		if (rcode == RCODE_COMPLETE)
613 			memcpy(rsp->data, payload, rsp->length);
614 
615 		rsp->rcode = rcode;
616 		rsp->request_tstamp = request_tstamp;
617 		rsp->response_tstamp = response_tstamp;
618 
619 		queue_event(client, &e->event, rsp, sizeof(*rsp) + rsp->length, NULL, 0);
620 
621 		break;
622 	}
623 	default:
624 		WARN_ON(1);
625 		break;
626 	}
627 
628 	// Drop the xarray's reference.
629 	client_put(client);
630 }
631 
632 static int init_request(struct client *client,
633 			struct fw_cdev_send_request *request,
634 			int destination_id, int speed)
635 {
636 	struct outbound_transaction_event *e;
637 	void *payload;
638 	int ret;
639 
640 	if (request->tcode != TCODE_STREAM_DATA &&
641 	    (request->length > 4096 || request->length > 512 << speed))
642 		return -EIO;
643 
644 	if (request->tcode == TCODE_WRITE_QUADLET_REQUEST &&
645 	    request->length < 4)
646 		return -EINVAL;
647 
648 	e = kmalloc(sizeof(*e) + request->length, GFP_KERNEL);
649 	if (e == NULL)
650 		return -ENOMEM;
651 	e->client = client;
652 
653 	if (client->version < FW_CDEV_VERSION_EVENT_ASYNC_TSTAMP) {
654 		struct fw_cdev_event_response *rsp = &e->rsp.without_tstamp;
655 
656 		rsp->type = FW_CDEV_EVENT_RESPONSE;
657 		rsp->length = request->length;
658 		rsp->closure = request->closure;
659 		payload = rsp->data;
660 	} else {
661 		struct fw_cdev_event_response2 *rsp = &e->rsp.with_tstamp;
662 
663 		rsp->type = FW_CDEV_EVENT_RESPONSE2;
664 		rsp->length = request->length;
665 		rsp->closure = request->closure;
666 		payload = rsp->data;
667 	}
668 
669 	if (request->data && copy_from_user(payload, u64_to_uptr(request->data), request->length)) {
670 		ret = -EFAULT;
671 		goto failed;
672 	}
673 
674 	e->r.resource.release = release_transaction;
675 	ret = add_client_resource(client, &e->r.resource, GFP_KERNEL);
676 	if (ret < 0)
677 		goto failed;
678 
679 	fw_send_request_with_tstamp(client->device->card, &e->r.transaction, request->tcode,
680 				    destination_id, request->generation, speed, request->offset,
681 				    payload, request->length, complete_transaction, e);
682 	return 0;
683 
684  failed:
685 	kfree(e);
686 
687 	return ret;
688 }
689 
690 static int ioctl_send_request(struct client *client, union ioctl_arg *arg)
691 {
692 	switch (arg->send_request.tcode) {
693 	case TCODE_WRITE_QUADLET_REQUEST:
694 	case TCODE_WRITE_BLOCK_REQUEST:
695 	case TCODE_READ_QUADLET_REQUEST:
696 	case TCODE_READ_BLOCK_REQUEST:
697 	case TCODE_LOCK_MASK_SWAP:
698 	case TCODE_LOCK_COMPARE_SWAP:
699 	case TCODE_LOCK_FETCH_ADD:
700 	case TCODE_LOCK_LITTLE_ADD:
701 	case TCODE_LOCK_BOUNDED_ADD:
702 	case TCODE_LOCK_WRAP_ADD:
703 	case TCODE_LOCK_VENDOR_DEPENDENT:
704 		break;
705 	default:
706 		return -EINVAL;
707 	}
708 
709 	return init_request(client, &arg->send_request, client->device->node_id,
710 			    client->device->max_speed);
711 }
712 
713 static void release_request(struct client *client,
714 			    struct client_resource *resource)
715 {
716 	struct inbound_transaction_resource *r = to_inbound_transaction_resource(resource);
717 
718 	if (r->is_fcp)
719 		fw_request_put(r->request);
720 	else
721 		fw_send_response(r->card, r->request, RCODE_CONFLICT_ERROR);
722 
723 	fw_card_put(r->card);
724 	kfree(r);
725 }
726 
727 static void handle_request(struct fw_card *card, struct fw_request *request,
728 			   int tcode, int destination, int source,
729 			   int generation, unsigned long long offset,
730 			   void *payload, size_t length, void *callback_data)
731 {
732 	struct address_handler_resource *handler = callback_data;
733 	bool is_fcp = is_in_fcp_region(offset, length);
734 	struct inbound_transaction_resource *r;
735 	struct inbound_transaction_event *e;
736 	size_t event_size0;
737 	int ret;
738 
739 	/* card may be different from handler->client->device->card */
740 	fw_card_get(card);
741 
742 	// Extend the lifetime of data for request so that its payload is safely accessible in
743 	// the process context for the client.
744 	if (is_fcp)
745 		fw_request_get(request);
746 
747 	r = kmalloc(sizeof(*r), GFP_ATOMIC);
748 	e = kmalloc(sizeof(*e), GFP_ATOMIC);
749 	if (r == NULL || e == NULL)
750 		goto failed;
751 
752 	r->card    = card;
753 	r->request = request;
754 	r->is_fcp  = is_fcp;
755 	r->data    = payload;
756 	r->length  = length;
757 
758 	r->resource.release = release_request;
759 	ret = add_client_resource(handler->client, &r->resource, GFP_ATOMIC);
760 	if (ret < 0)
761 		goto failed;
762 
763 	if (handler->client->version < FW_CDEV_VERSION_EVENT_REQUEST2) {
764 		struct fw_cdev_event_request *req = &e->req.request;
765 
766 		if (tcode & 0x10)
767 			tcode = TCODE_LOCK_REQUEST;
768 
769 		req->type	= FW_CDEV_EVENT_REQUEST;
770 		req->tcode	= tcode;
771 		req->offset	= offset;
772 		req->length	= length;
773 		req->handle	= r->resource.handle;
774 		req->closure	= handler->closure;
775 		event_size0	= sizeof(*req);
776 	} else if (handler->client->version < FW_CDEV_VERSION_EVENT_ASYNC_TSTAMP) {
777 		struct fw_cdev_event_request2 *req = &e->req.request2;
778 
779 		req->type	= FW_CDEV_EVENT_REQUEST2;
780 		req->tcode	= tcode;
781 		req->offset	= offset;
782 		req->source_node_id = source;
783 		req->destination_node_id = destination;
784 		req->card	= card->index;
785 		req->generation	= generation;
786 		req->length	= length;
787 		req->handle	= r->resource.handle;
788 		req->closure	= handler->closure;
789 		event_size0	= sizeof(*req);
790 	} else {
791 		struct fw_cdev_event_request3 *req = &e->req.with_tstamp;
792 
793 		req->type	= FW_CDEV_EVENT_REQUEST3;
794 		req->tcode	= tcode;
795 		req->offset	= offset;
796 		req->source_node_id = source;
797 		req->destination_node_id = destination;
798 		req->card	= card->index;
799 		req->generation	= generation;
800 		req->length	= length;
801 		req->handle	= r->resource.handle;
802 		req->closure	= handler->closure;
803 		req->tstamp	= fw_request_get_timestamp(request);
804 		event_size0	= sizeof(*req);
805 	}
806 
807 	queue_event(handler->client, &e->event,
808 		    &e->req, event_size0, r->data, length);
809 	return;
810 
811  failed:
812 	kfree(r);
813 	kfree(e);
814 
815 	if (!is_fcp)
816 		fw_send_response(card, request, RCODE_CONFLICT_ERROR);
817 	else
818 		fw_request_put(request);
819 
820 	fw_card_put(card);
821 }
822 
823 static void release_address_handler(struct client *client,
824 				    struct client_resource *resource)
825 {
826 	struct address_handler_resource *r = to_address_handler_resource(resource);
827 
828 	fw_core_remove_address_handler(&r->handler);
829 	kfree(r);
830 }
831 
832 static int ioctl_allocate(struct client *client, union ioctl_arg *arg)
833 {
834 	struct fw_cdev_allocate *a = &arg->allocate;
835 	struct address_handler_resource *r;
836 	struct fw_address_region region;
837 	int ret;
838 
839 	r = kmalloc(sizeof(*r), GFP_KERNEL);
840 	if (r == NULL)
841 		return -ENOMEM;
842 
843 	region.start = a->offset;
844 	if (client->version < FW_CDEV_VERSION_ALLOCATE_REGION_END)
845 		region.end = a->offset + a->length;
846 	else
847 		region.end = a->region_end;
848 
849 	r->handler.length           = a->length;
850 	r->handler.address_callback = handle_request;
851 	r->handler.callback_data    = r;
852 	r->closure   = a->closure;
853 	r->client    = client;
854 
855 	ret = fw_core_add_address_handler(&r->handler, &region);
856 	if (ret < 0) {
857 		kfree(r);
858 		return ret;
859 	}
860 	a->offset = r->handler.offset;
861 
862 	r->resource.release = release_address_handler;
863 	ret = add_client_resource(client, &r->resource, GFP_KERNEL);
864 	if (ret < 0) {
865 		release_address_handler(client, &r->resource);
866 		return ret;
867 	}
868 	a->handle = r->resource.handle;
869 
870 	return 0;
871 }
872 
873 static int ioctl_deallocate(struct client *client, union ioctl_arg *arg)
874 {
875 	return release_client_resource(client, arg->deallocate.handle,
876 				       release_address_handler, NULL);
877 }
878 
879 static int ioctl_send_response(struct client *client, union ioctl_arg *arg)
880 {
881 	struct fw_cdev_send_response *a = &arg->send_response;
882 	struct client_resource *resource;
883 	struct inbound_transaction_resource *r;
884 	int ret = 0;
885 
886 	if (release_client_resource(client, a->handle,
887 				    release_request, &resource) < 0)
888 		return -EINVAL;
889 
890 	r = to_inbound_transaction_resource(resource);
891 	if (r->is_fcp) {
892 		fw_request_put(r->request);
893 		goto out;
894 	}
895 
896 	if (a->length != fw_get_response_length(r->request)) {
897 		ret = -EINVAL;
898 		fw_request_put(r->request);
899 		goto out;
900 	}
901 	if (copy_from_user(r->data, u64_to_uptr(a->data), a->length)) {
902 		ret = -EFAULT;
903 		fw_request_put(r->request);
904 		goto out;
905 	}
906 	fw_send_response(r->card, r->request, a->rcode);
907  out:
908 	fw_card_put(r->card);
909 	kfree(r);
910 
911 	return ret;
912 }
913 
914 static int ioctl_initiate_bus_reset(struct client *client, union ioctl_arg *arg)
915 {
916 	fw_schedule_bus_reset(client->device->card, true,
917 			arg->initiate_bus_reset.type == FW_CDEV_SHORT_RESET);
918 	return 0;
919 }
920 
921 static void release_descriptor(struct client *client,
922 			       struct client_resource *resource)
923 {
924 	struct descriptor_resource *r = to_descriptor_resource(resource);
925 
926 	fw_core_remove_descriptor(&r->descriptor);
927 	kfree(r);
928 }
929 
930 static int ioctl_add_descriptor(struct client *client, union ioctl_arg *arg)
931 {
932 	struct fw_cdev_add_descriptor *a = &arg->add_descriptor;
933 	struct descriptor_resource *r;
934 	int ret;
935 
936 	/* Access policy: Allow this ioctl only on local nodes' device files. */
937 	if (!client->device->is_local)
938 		return -ENOSYS;
939 
940 	if (a->length > 256)
941 		return -EINVAL;
942 
943 	r = kmalloc(struct_size(r, data, a->length), GFP_KERNEL);
944 	if (r == NULL)
945 		return -ENOMEM;
946 
947 	if (copy_from_user(r->data, u64_to_uptr(a->data),
948 			   flex_array_size(r, data, a->length))) {
949 		ret = -EFAULT;
950 		goto failed;
951 	}
952 
953 	r->descriptor.length    = a->length;
954 	r->descriptor.immediate = a->immediate;
955 	r->descriptor.key       = a->key;
956 	r->descriptor.data      = r->data;
957 
958 	ret = fw_core_add_descriptor(&r->descriptor);
959 	if (ret < 0)
960 		goto failed;
961 
962 	r->resource.release = release_descriptor;
963 	ret = add_client_resource(client, &r->resource, GFP_KERNEL);
964 	if (ret < 0) {
965 		fw_core_remove_descriptor(&r->descriptor);
966 		goto failed;
967 	}
968 	a->handle = r->resource.handle;
969 
970 	return 0;
971  failed:
972 	kfree(r);
973 
974 	return ret;
975 }
976 
977 static int ioctl_remove_descriptor(struct client *client, union ioctl_arg *arg)
978 {
979 	return release_client_resource(client, arg->remove_descriptor.handle,
980 				       release_descriptor, NULL);
981 }
982 
983 static void iso_callback(struct fw_iso_context *context, u32 cycle,
984 			 size_t header_length, void *header, void *data)
985 {
986 	struct client *client = data;
987 	struct iso_interrupt_event *e;
988 
989 	e = kmalloc(sizeof(*e) + header_length, GFP_KERNEL);
990 	if (e == NULL)
991 		return;
992 
993 	e->interrupt.type      = FW_CDEV_EVENT_ISO_INTERRUPT;
994 	e->interrupt.closure   = client->iso_closure;
995 	e->interrupt.cycle     = cycle;
996 	e->interrupt.header_length = header_length;
997 	memcpy(e->interrupt.header, header, header_length);
998 	queue_event(client, &e->event, &e->interrupt,
999 		    sizeof(e->interrupt) + header_length, NULL, 0);
1000 }
1001 
1002 static void iso_mc_callback(struct fw_iso_context *context,
1003 			    dma_addr_t completed, void *data)
1004 {
1005 	struct client *client = data;
1006 	struct iso_interrupt_mc_event *e;
1007 
1008 	e = kmalloc(sizeof(*e), GFP_KERNEL);
1009 	if (e == NULL)
1010 		return;
1011 
1012 	e->interrupt.type      = FW_CDEV_EVENT_ISO_INTERRUPT_MULTICHANNEL;
1013 	e->interrupt.closure   = client->iso_closure;
1014 	e->interrupt.completed = fw_iso_buffer_lookup(&client->buffer,
1015 						      completed);
1016 	queue_event(client, &e->event, &e->interrupt,
1017 		    sizeof(e->interrupt), NULL, 0);
1018 }
1019 
1020 static enum dma_data_direction iso_dma_direction(struct fw_iso_context *context)
1021 {
1022 		if (context->type == FW_ISO_CONTEXT_TRANSMIT)
1023 			return DMA_TO_DEVICE;
1024 		else
1025 			return DMA_FROM_DEVICE;
1026 }
1027 
1028 static struct fw_iso_context *fw_iso_mc_context_create(struct fw_card *card,
1029 						fw_iso_mc_callback_t callback,
1030 						void *callback_data)
1031 {
1032 	struct fw_iso_context *ctx;
1033 
1034 	ctx = fw_iso_context_create(card, FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL,
1035 				    0, 0, 0, NULL, callback_data);
1036 	if (!IS_ERR(ctx))
1037 		ctx->callback.mc = callback;
1038 
1039 	return ctx;
1040 }
1041 
1042 static int ioctl_create_iso_context(struct client *client, union ioctl_arg *arg)
1043 {
1044 	struct fw_cdev_create_iso_context *a = &arg->create_iso_context;
1045 	struct fw_iso_context *context;
1046 	union fw_iso_callback cb;
1047 	int ret;
1048 
1049 	BUILD_BUG_ON(FW_CDEV_ISO_CONTEXT_TRANSMIT != FW_ISO_CONTEXT_TRANSMIT ||
1050 		     FW_CDEV_ISO_CONTEXT_RECEIVE  != FW_ISO_CONTEXT_RECEIVE  ||
1051 		     FW_CDEV_ISO_CONTEXT_RECEIVE_MULTICHANNEL !=
1052 					FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL);
1053 
1054 	switch (a->type) {
1055 	case FW_ISO_CONTEXT_TRANSMIT:
1056 		if (a->speed > SCODE_3200 || a->channel > 63)
1057 			return -EINVAL;
1058 
1059 		cb.sc = iso_callback;
1060 		break;
1061 
1062 	case FW_ISO_CONTEXT_RECEIVE:
1063 		if (a->header_size < 4 || (a->header_size & 3) ||
1064 		    a->channel > 63)
1065 			return -EINVAL;
1066 
1067 		cb.sc = iso_callback;
1068 		break;
1069 
1070 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
1071 		cb.mc = iso_mc_callback;
1072 		break;
1073 
1074 	default:
1075 		return -EINVAL;
1076 	}
1077 
1078 	if (a->type == FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL)
1079 		context = fw_iso_mc_context_create(client->device->card, cb.mc,
1080 						   client);
1081 	else
1082 		context = fw_iso_context_create(client->device->card, a->type,
1083 						a->channel, a->speed,
1084 						a->header_size, cb.sc, client);
1085 	if (IS_ERR(context))
1086 		return PTR_ERR(context);
1087 	if (client->version < FW_CDEV_VERSION_AUTO_FLUSH_ISO_OVERFLOW)
1088 		context->drop_overflow_headers = true;
1089 
1090 	// We only support one context at this time.
1091 	guard(spinlock_irq)(&client->lock);
1092 
1093 	if (client->iso_context != NULL) {
1094 		fw_iso_context_destroy(context);
1095 
1096 		return -EBUSY;
1097 	}
1098 	if (!client->buffer_is_mapped) {
1099 		ret = fw_iso_buffer_map_dma(&client->buffer,
1100 					    client->device->card,
1101 					    iso_dma_direction(context));
1102 		if (ret < 0) {
1103 			fw_iso_context_destroy(context);
1104 
1105 			return ret;
1106 		}
1107 		client->buffer_is_mapped = true;
1108 	}
1109 	client->iso_closure = a->closure;
1110 	client->iso_context = context;
1111 
1112 	a->handle = 0;
1113 
1114 	return 0;
1115 }
1116 
1117 static int ioctl_set_iso_channels(struct client *client, union ioctl_arg *arg)
1118 {
1119 	struct fw_cdev_set_iso_channels *a = &arg->set_iso_channels;
1120 	struct fw_iso_context *ctx = client->iso_context;
1121 
1122 	if (ctx == NULL || a->handle != 0)
1123 		return -EINVAL;
1124 
1125 	return fw_iso_context_set_channels(ctx, &a->channels);
1126 }
1127 
1128 /* Macros for decoding the iso packet control header. */
1129 #define GET_PAYLOAD_LENGTH(v)	((v) & 0xffff)
1130 #define GET_INTERRUPT(v)	(((v) >> 16) & 0x01)
1131 #define GET_SKIP(v)		(((v) >> 17) & 0x01)
1132 #define GET_TAG(v)		(((v) >> 18) & 0x03)
1133 #define GET_SY(v)		(((v) >> 20) & 0x0f)
1134 #define GET_HEADER_LENGTH(v)	(((v) >> 24) & 0xff)
1135 
1136 static int ioctl_queue_iso(struct client *client, union ioctl_arg *arg)
1137 {
1138 	struct fw_cdev_queue_iso *a = &arg->queue_iso;
1139 	struct fw_cdev_iso_packet __user *p, *end, *next;
1140 	struct fw_iso_context *ctx = client->iso_context;
1141 	unsigned long payload, buffer_end, transmit_header_bytes = 0;
1142 	u32 control;
1143 	int count;
1144 	DEFINE_RAW_FLEX(struct fw_iso_packet, u, header, 64);
1145 
1146 	if (ctx == NULL || a->handle != 0)
1147 		return -EINVAL;
1148 
1149 	/*
1150 	 * If the user passes a non-NULL data pointer, has mmap()'ed
1151 	 * the iso buffer, and the pointer points inside the buffer,
1152 	 * we setup the payload pointers accordingly.  Otherwise we
1153 	 * set them both to 0, which will still let packets with
1154 	 * payload_length == 0 through.  In other words, if no packets
1155 	 * use the indirect payload, the iso buffer need not be mapped
1156 	 * and the a->data pointer is ignored.
1157 	 */
1158 	payload = (unsigned long)a->data - client->vm_start;
1159 	buffer_end = client->buffer.page_count << PAGE_SHIFT;
1160 	if (a->data == 0 || client->buffer.pages == NULL ||
1161 	    payload >= buffer_end) {
1162 		payload = 0;
1163 		buffer_end = 0;
1164 	}
1165 
1166 	if (ctx->type == FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL && payload & 3)
1167 		return -EINVAL;
1168 
1169 	p = (struct fw_cdev_iso_packet __user *)u64_to_uptr(a->packets);
1170 
1171 	end = (void __user *)p + a->size;
1172 	count = 0;
1173 	while (p < end) {
1174 		if (get_user(control, &p->control))
1175 			return -EFAULT;
1176 		u->payload_length = GET_PAYLOAD_LENGTH(control);
1177 		u->interrupt = GET_INTERRUPT(control);
1178 		u->skip = GET_SKIP(control);
1179 		u->tag = GET_TAG(control);
1180 		u->sy = GET_SY(control);
1181 		u->header_length = GET_HEADER_LENGTH(control);
1182 
1183 		switch (ctx->type) {
1184 		case FW_ISO_CONTEXT_TRANSMIT:
1185 			if (u->header_length & 3)
1186 				return -EINVAL;
1187 			transmit_header_bytes = u->header_length;
1188 			break;
1189 
1190 		case FW_ISO_CONTEXT_RECEIVE:
1191 			if (u->header_length == 0 ||
1192 			    u->header_length % ctx->header_size != 0)
1193 				return -EINVAL;
1194 			break;
1195 
1196 		case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
1197 			if (u->payload_length == 0 ||
1198 			    u->payload_length & 3)
1199 				return -EINVAL;
1200 			break;
1201 		}
1202 
1203 		next = (struct fw_cdev_iso_packet __user *)
1204 			&p->header[transmit_header_bytes / 4];
1205 		if (next > end)
1206 			return -EINVAL;
1207 		if (copy_from_user
1208 		    (u->header, p->header, transmit_header_bytes))
1209 			return -EFAULT;
1210 		if (u->skip && ctx->type == FW_ISO_CONTEXT_TRANSMIT &&
1211 		    u->header_length + u->payload_length > 0)
1212 			return -EINVAL;
1213 		if (payload + u->payload_length > buffer_end)
1214 			return -EINVAL;
1215 
1216 		if (fw_iso_context_queue(ctx, u, &client->buffer, payload))
1217 			break;
1218 
1219 		p = next;
1220 		payload += u->payload_length;
1221 		count++;
1222 	}
1223 	fw_iso_context_queue_flush(ctx);
1224 
1225 	a->size    -= uptr_to_u64(p) - a->packets;
1226 	a->packets  = uptr_to_u64(p);
1227 	a->data     = client->vm_start + payload;
1228 
1229 	return count;
1230 }
1231 
1232 static int ioctl_start_iso(struct client *client, union ioctl_arg *arg)
1233 {
1234 	struct fw_cdev_start_iso *a = &arg->start_iso;
1235 
1236 	BUILD_BUG_ON(
1237 	    FW_CDEV_ISO_CONTEXT_MATCH_TAG0 != FW_ISO_CONTEXT_MATCH_TAG0 ||
1238 	    FW_CDEV_ISO_CONTEXT_MATCH_TAG1 != FW_ISO_CONTEXT_MATCH_TAG1 ||
1239 	    FW_CDEV_ISO_CONTEXT_MATCH_TAG2 != FW_ISO_CONTEXT_MATCH_TAG2 ||
1240 	    FW_CDEV_ISO_CONTEXT_MATCH_TAG3 != FW_ISO_CONTEXT_MATCH_TAG3 ||
1241 	    FW_CDEV_ISO_CONTEXT_MATCH_ALL_TAGS != FW_ISO_CONTEXT_MATCH_ALL_TAGS);
1242 
1243 	if (client->iso_context == NULL || a->handle != 0)
1244 		return -EINVAL;
1245 
1246 	if (client->iso_context->type == FW_ISO_CONTEXT_RECEIVE &&
1247 	    (a->tags == 0 || a->tags > 15 || a->sync > 15))
1248 		return -EINVAL;
1249 
1250 	return fw_iso_context_start(client->iso_context,
1251 				    a->cycle, a->sync, a->tags);
1252 }
1253 
1254 static int ioctl_stop_iso(struct client *client, union ioctl_arg *arg)
1255 {
1256 	struct fw_cdev_stop_iso *a = &arg->stop_iso;
1257 
1258 	if (client->iso_context == NULL || a->handle != 0)
1259 		return -EINVAL;
1260 
1261 	return fw_iso_context_stop(client->iso_context);
1262 }
1263 
1264 static int ioctl_flush_iso(struct client *client, union ioctl_arg *arg)
1265 {
1266 	struct fw_cdev_flush_iso *a = &arg->flush_iso;
1267 
1268 	if (client->iso_context == NULL || a->handle != 0)
1269 		return -EINVAL;
1270 
1271 	return fw_iso_context_flush_completions(client->iso_context);
1272 }
1273 
1274 static int ioctl_get_cycle_timer2(struct client *client, union ioctl_arg *arg)
1275 {
1276 	struct fw_cdev_get_cycle_timer2 *a = &arg->get_cycle_timer2;
1277 	struct fw_card *card = client->device->card;
1278 	struct timespec64 ts = {0, 0};
1279 	u32 cycle_time = 0;
1280 	int ret;
1281 
1282 	guard(irq)();
1283 
1284 	ret = fw_card_read_cycle_time(card, &cycle_time);
1285 	if (ret < 0)
1286 		return ret;
1287 
1288 	switch (a->clk_id) {
1289 	case CLOCK_REALTIME:      ktime_get_real_ts64(&ts);	break;
1290 	case CLOCK_MONOTONIC:     ktime_get_ts64(&ts);		break;
1291 	case CLOCK_MONOTONIC_RAW: ktime_get_raw_ts64(&ts);	break;
1292 	default:
1293 		return -EINVAL;
1294 	}
1295 
1296 	a->tv_sec      = ts.tv_sec;
1297 	a->tv_nsec     = ts.tv_nsec;
1298 	a->cycle_timer = cycle_time;
1299 
1300 	return 0;
1301 }
1302 
1303 static int ioctl_get_cycle_timer(struct client *client, union ioctl_arg *arg)
1304 {
1305 	struct fw_cdev_get_cycle_timer *a = &arg->get_cycle_timer;
1306 	struct fw_cdev_get_cycle_timer2 ct2;
1307 
1308 	ct2.clk_id = CLOCK_REALTIME;
1309 	ioctl_get_cycle_timer2(client, (union ioctl_arg *)&ct2);
1310 
1311 	a->local_time = ct2.tv_sec * USEC_PER_SEC + ct2.tv_nsec / NSEC_PER_USEC;
1312 	a->cycle_timer = ct2.cycle_timer;
1313 
1314 	return 0;
1315 }
1316 
1317 static void iso_resource_work(struct work_struct *work)
1318 {
1319 	struct iso_resource_event *e;
1320 	struct iso_resource *r = from_work(r, work, work.work);
1321 	struct client *client = r->client;
1322 	unsigned long index = r->resource.handle;
1323 	int generation, channel, bandwidth, todo;
1324 	bool skip, free, success;
1325 
1326 	scoped_guard(spinlock_irq, &client->lock) {
1327 		generation = client->device->generation;
1328 		todo = r->todo;
1329 		// Allow 1000ms grace period for other reallocations.
1330 		if (todo == ISO_RES_ALLOC &&
1331 		    time_is_after_jiffies64(client->device->card->reset_jiffies + secs_to_jiffies(1))) {
1332 			schedule_iso_resource(r, msecs_to_jiffies(333));
1333 			skip = true;
1334 		} else {
1335 			// We could be called twice within the same generation.
1336 			skip = todo == ISO_RES_REALLOC &&
1337 			       r->generation == generation;
1338 		}
1339 		free = todo == ISO_RES_DEALLOC ||
1340 		       todo == ISO_RES_ALLOC_ONCE ||
1341 		       todo == ISO_RES_DEALLOC_ONCE;
1342 		r->generation = generation;
1343 	}
1344 
1345 	if (skip)
1346 		goto out;
1347 
1348 	bandwidth = r->bandwidth;
1349 
1350 	fw_iso_resource_manage(client->device->card, generation,
1351 			r->channels, &channel, &bandwidth,
1352 			todo == ISO_RES_ALLOC ||
1353 			todo == ISO_RES_REALLOC ||
1354 			todo == ISO_RES_ALLOC_ONCE);
1355 	/*
1356 	 * Is this generation outdated already?  As long as this resource sticks
1357 	 * in the xarray, it will be scheduled again for a newer generation or at
1358 	 * shutdown.
1359 	 */
1360 	if (channel == -EAGAIN &&
1361 	    (todo == ISO_RES_ALLOC || todo == ISO_RES_REALLOC))
1362 		goto out;
1363 
1364 	success = channel >= 0 || bandwidth > 0;
1365 
1366 	scoped_guard(spinlock_irq, &client->lock) {
1367 		// Transit from allocation to reallocation, except if the client
1368 		// requested deallocation in the meantime.
1369 		if (r->todo == ISO_RES_ALLOC)
1370 			r->todo = ISO_RES_REALLOC;
1371 		// Allocation or reallocation failure?  Pull this resource out of the
1372 		// xarray and prepare for deletion, unless the client is shutting down.
1373 		if (r->todo == ISO_RES_REALLOC && !success &&
1374 		    !client->in_shutdown &&
1375 		    xa_erase(&client->resource_xa, index)) {
1376 			client_put(client);
1377 			free = true;
1378 		}
1379 	}
1380 
1381 	if (todo == ISO_RES_ALLOC && channel >= 0)
1382 		r->channels = 1ULL << channel;
1383 
1384 	if (todo == ISO_RES_REALLOC && success)
1385 		goto out;
1386 
1387 	if (todo == ISO_RES_ALLOC || todo == ISO_RES_ALLOC_ONCE) {
1388 		e = r->e_alloc;
1389 		r->e_alloc = NULL;
1390 	} else {
1391 		e = r->e_dealloc;
1392 		r->e_dealloc = NULL;
1393 	}
1394 	e->iso_resource.handle    = r->resource.handle;
1395 	e->iso_resource.channel   = channel;
1396 	e->iso_resource.bandwidth = bandwidth;
1397 
1398 	queue_event(client, &e->event,
1399 		    &e->iso_resource, sizeof(e->iso_resource), NULL, 0);
1400 
1401 	if (free) {
1402 		cancel_delayed_work(&r->work);
1403 		kfree(r->e_alloc);
1404 		kfree(r->e_dealloc);
1405 		kfree(r);
1406 	}
1407  out:
1408 	client_put(client);
1409 }
1410 
1411 static void release_iso_resource(struct client *client,
1412 				 struct client_resource *resource)
1413 {
1414 	struct iso_resource *r = to_iso_resource(resource);
1415 
1416 	guard(spinlock_irq)(&client->lock);
1417 
1418 	r->todo = ISO_RES_DEALLOC;
1419 	schedule_iso_resource(r, 0);
1420 }
1421 
1422 static int init_iso_resource(struct client *client,
1423 		struct fw_cdev_allocate_iso_resource *request, int todo)
1424 {
1425 	struct iso_resource_event *e1, *e2;
1426 	struct iso_resource *r;
1427 	int ret;
1428 
1429 	if ((request->channels == 0 && request->bandwidth == 0) ||
1430 	    request->bandwidth > BANDWIDTH_AVAILABLE_INITIAL)
1431 		return -EINVAL;
1432 
1433 	r  = kmalloc(sizeof(*r), GFP_KERNEL);
1434 	e1 = kmalloc(sizeof(*e1), GFP_KERNEL);
1435 	e2 = kmalloc(sizeof(*e2), GFP_KERNEL);
1436 	if (r == NULL || e1 == NULL || e2 == NULL) {
1437 		ret = -ENOMEM;
1438 		goto fail;
1439 	}
1440 
1441 	INIT_DELAYED_WORK(&r->work, iso_resource_work);
1442 	r->client	= client;
1443 	r->todo		= todo;
1444 	r->generation	= -1;
1445 	r->channels	= request->channels;
1446 	r->bandwidth	= request->bandwidth;
1447 	r->e_alloc	= e1;
1448 	r->e_dealloc	= e2;
1449 
1450 	e1->iso_resource.closure = request->closure;
1451 	e1->iso_resource.type    = FW_CDEV_EVENT_ISO_RESOURCE_ALLOCATED;
1452 	e2->iso_resource.closure = request->closure;
1453 	e2->iso_resource.type    = FW_CDEV_EVENT_ISO_RESOURCE_DEALLOCATED;
1454 
1455 	if (todo == ISO_RES_ALLOC) {
1456 		r->resource.release = release_iso_resource;
1457 		ret = add_client_resource(client, &r->resource, GFP_KERNEL);
1458 		if (ret < 0)
1459 			goto fail;
1460 	} else {
1461 		r->resource.release = NULL;
1462 		r->resource.handle = -1;
1463 		schedule_iso_resource(r, 0);
1464 	}
1465 	request->handle = r->resource.handle;
1466 
1467 	return 0;
1468  fail:
1469 	kfree(r);
1470 	kfree(e1);
1471 	kfree(e2);
1472 
1473 	return ret;
1474 }
1475 
1476 static int ioctl_allocate_iso_resource(struct client *client,
1477 				       union ioctl_arg *arg)
1478 {
1479 	return init_iso_resource(client,
1480 			&arg->allocate_iso_resource, ISO_RES_ALLOC);
1481 }
1482 
1483 static int ioctl_deallocate_iso_resource(struct client *client,
1484 					 union ioctl_arg *arg)
1485 {
1486 	return release_client_resource(client,
1487 			arg->deallocate.handle, release_iso_resource, NULL);
1488 }
1489 
1490 static int ioctl_allocate_iso_resource_once(struct client *client,
1491 					    union ioctl_arg *arg)
1492 {
1493 	return init_iso_resource(client,
1494 			&arg->allocate_iso_resource, ISO_RES_ALLOC_ONCE);
1495 }
1496 
1497 static int ioctl_deallocate_iso_resource_once(struct client *client,
1498 					      union ioctl_arg *arg)
1499 {
1500 	return init_iso_resource(client,
1501 			&arg->allocate_iso_resource, ISO_RES_DEALLOC_ONCE);
1502 }
1503 
1504 /*
1505  * Returns a speed code:  Maximum speed to or from this device,
1506  * limited by the device's link speed, the local node's link speed,
1507  * and all PHY port speeds between the two links.
1508  */
1509 static int ioctl_get_speed(struct client *client, union ioctl_arg *arg)
1510 {
1511 	return client->device->max_speed;
1512 }
1513 
1514 static int ioctl_send_broadcast_request(struct client *client,
1515 					union ioctl_arg *arg)
1516 {
1517 	struct fw_cdev_send_request *a = &arg->send_request;
1518 
1519 	switch (a->tcode) {
1520 	case TCODE_WRITE_QUADLET_REQUEST:
1521 	case TCODE_WRITE_BLOCK_REQUEST:
1522 		break;
1523 	default:
1524 		return -EINVAL;
1525 	}
1526 
1527 	/* Security policy: Only allow accesses to Units Space. */
1528 	if (a->offset < CSR_REGISTER_BASE + CSR_CONFIG_ROM_END)
1529 		return -EACCES;
1530 
1531 	return init_request(client, a, LOCAL_BUS | 0x3f, SCODE_100);
1532 }
1533 
1534 static int ioctl_send_stream_packet(struct client *client, union ioctl_arg *arg)
1535 {
1536 	struct fw_cdev_send_stream_packet *a = &arg->send_stream_packet;
1537 	struct fw_cdev_send_request request;
1538 	int dest;
1539 
1540 	if (a->speed > client->device->card->link_speed ||
1541 	    a->length > 1024 << a->speed)
1542 		return -EIO;
1543 
1544 	if (a->tag > 3 || a->channel > 63 || a->sy > 15)
1545 		return -EINVAL;
1546 
1547 	dest = fw_stream_packet_destination_id(a->tag, a->channel, a->sy);
1548 	request.tcode		= TCODE_STREAM_DATA;
1549 	request.length		= a->length;
1550 	request.closure		= a->closure;
1551 	request.data		= a->data;
1552 	request.generation	= a->generation;
1553 
1554 	return init_request(client, &request, dest, a->speed);
1555 }
1556 
1557 static void outbound_phy_packet_callback(struct fw_packet *packet,
1558 					 struct fw_card *card, int status)
1559 {
1560 	struct outbound_phy_packet_event *e =
1561 		container_of(packet, struct outbound_phy_packet_event, p);
1562 	struct client *e_client = e->client;
1563 	u32 rcode;
1564 
1565 	trace_async_phy_outbound_complete((uintptr_t)packet, card->index, status, packet->generation,
1566 					  packet->timestamp);
1567 
1568 	switch (status) {
1569 	// expected:
1570 	case ACK_COMPLETE:
1571 		rcode = RCODE_COMPLETE;
1572 		break;
1573 	// should never happen with PHY packets:
1574 	case ACK_PENDING:
1575 		rcode = RCODE_COMPLETE;
1576 		break;
1577 	case ACK_BUSY_X:
1578 	case ACK_BUSY_A:
1579 	case ACK_BUSY_B:
1580 		rcode = RCODE_BUSY;
1581 		break;
1582 	case ACK_DATA_ERROR:
1583 		rcode = RCODE_DATA_ERROR;
1584 		break;
1585 	case ACK_TYPE_ERROR:
1586 		rcode = RCODE_TYPE_ERROR;
1587 		break;
1588 	// stale generation; cancelled; on certain controllers: no ack
1589 	default:
1590 		rcode = status;
1591 		break;
1592 	}
1593 
1594 	switch (e->phy_packet.without_tstamp.type) {
1595 	case FW_CDEV_EVENT_PHY_PACKET_SENT:
1596 	{
1597 		struct fw_cdev_event_phy_packet *pp = &e->phy_packet.without_tstamp;
1598 
1599 		pp->rcode = rcode;
1600 		pp->data[0] = packet->timestamp;
1601 		queue_event(e->client, &e->event, &e->phy_packet, sizeof(*pp) + pp->length,
1602 			    NULL, 0);
1603 		break;
1604 	}
1605 	case FW_CDEV_EVENT_PHY_PACKET_SENT2:
1606 	{
1607 		struct fw_cdev_event_phy_packet2 *pp = &e->phy_packet.with_tstamp;
1608 
1609 		pp->rcode = rcode;
1610 		pp->tstamp = packet->timestamp;
1611 		queue_event(e->client, &e->event, &e->phy_packet, sizeof(*pp) + pp->length,
1612 			    NULL, 0);
1613 		break;
1614 	}
1615 	default:
1616 		WARN_ON(1);
1617 		break;
1618 	}
1619 
1620 	client_put(e_client);
1621 }
1622 
1623 static int ioctl_send_phy_packet(struct client *client, union ioctl_arg *arg)
1624 {
1625 	struct fw_cdev_send_phy_packet *a = &arg->send_phy_packet;
1626 	struct fw_card *card = client->device->card;
1627 	struct outbound_phy_packet_event *e;
1628 
1629 	/* Access policy: Allow this ioctl only on local nodes' device files. */
1630 	if (!client->device->is_local)
1631 		return -ENOSYS;
1632 
1633 	e = kzalloc(sizeof(*e) + sizeof(a->data), GFP_KERNEL);
1634 	if (e == NULL)
1635 		return -ENOMEM;
1636 
1637 	client_get(client);
1638 	e->client		= client;
1639 	e->p.speed		= SCODE_100;
1640 	e->p.generation		= a->generation;
1641 	async_header_set_tcode(e->p.header, TCODE_LINK_INTERNAL);
1642 	e->p.header[1]		= a->data[0];
1643 	e->p.header[2]		= a->data[1];
1644 	e->p.header_length	= 12;
1645 	e->p.callback		= outbound_phy_packet_callback;
1646 
1647 	if (client->version < FW_CDEV_VERSION_EVENT_ASYNC_TSTAMP) {
1648 		struct fw_cdev_event_phy_packet *pp = &e->phy_packet.without_tstamp;
1649 
1650 		pp->closure = a->closure;
1651 		pp->type = FW_CDEV_EVENT_PHY_PACKET_SENT;
1652 		if (is_ping_packet(a->data))
1653 			pp->length = 4;
1654 	} else {
1655 		struct fw_cdev_event_phy_packet2 *pp = &e->phy_packet.with_tstamp;
1656 
1657 		pp->closure = a->closure;
1658 		pp->type = FW_CDEV_EVENT_PHY_PACKET_SENT2;
1659 		// Keep the data field so that application can match the response event to the
1660 		// request.
1661 		pp->length = sizeof(a->data);
1662 		memcpy(pp->data, a->data, sizeof(a->data));
1663 	}
1664 
1665 	trace_async_phy_outbound_initiate((uintptr_t)&e->p, card->index, e->p.generation,
1666 					  e->p.header[1], e->p.header[2]);
1667 
1668 	card->driver->send_request(card, &e->p);
1669 
1670 	return 0;
1671 }
1672 
1673 static int ioctl_receive_phy_packets(struct client *client, union ioctl_arg *arg)
1674 {
1675 	struct fw_cdev_receive_phy_packets *a = &arg->receive_phy_packets;
1676 
1677 	/* Access policy: Allow this ioctl only on local nodes' device files. */
1678 	if (!client->device->is_local)
1679 		return -ENOSYS;
1680 
1681 	// NOTE: This can be without irq when we can guarantee that __fw_send_request() for local
1682 	// destination never runs in any type of IRQ context.
1683 	scoped_guard(spinlock_irq, &phy_receiver_list_lock)
1684 		list_move_tail(&client->phy_receiver_link, &phy_receiver_list);
1685 
1686 	client->phy_receiver_closure = a->closure;
1687 
1688 	return 0;
1689 }
1690 
1691 void fw_cdev_handle_phy_packet(struct fw_card *card, struct fw_packet *p)
1692 {
1693 	struct client *client;
1694 
1695 	// NOTE: This can be without irqsave when we can guarantee that __fw_send_request() for local
1696 	// destination never runs in any type of IRQ context.
1697 	guard(spinlock_irqsave)(&phy_receiver_list_lock);
1698 
1699 	list_for_each_entry(client, &phy_receiver_list, phy_receiver_link) {
1700 		struct inbound_phy_packet_event *e;
1701 
1702 		if (client->device->card != card)
1703 			continue;
1704 
1705 		e = kmalloc(sizeof(*e) + 8, GFP_ATOMIC);
1706 		if (e == NULL)
1707 			break;
1708 
1709 		if (client->version < FW_CDEV_VERSION_EVENT_ASYNC_TSTAMP) {
1710 			struct fw_cdev_event_phy_packet *pp = &e->phy_packet.without_tstamp;
1711 
1712 			pp->closure = client->phy_receiver_closure;
1713 			pp->type = FW_CDEV_EVENT_PHY_PACKET_RECEIVED;
1714 			pp->rcode = RCODE_COMPLETE;
1715 			pp->length = 8;
1716 			pp->data[0] = p->header[1];
1717 			pp->data[1] = p->header[2];
1718 			queue_event(client, &e->event, &e->phy_packet, sizeof(*pp) + 8, NULL, 0);
1719 		} else {
1720 			struct fw_cdev_event_phy_packet2 *pp = &e->phy_packet.with_tstamp;
1721 
1722 			pp = &e->phy_packet.with_tstamp;
1723 			pp->closure = client->phy_receiver_closure;
1724 			pp->type = FW_CDEV_EVENT_PHY_PACKET_RECEIVED2;
1725 			pp->rcode = RCODE_COMPLETE;
1726 			pp->length = 8;
1727 			pp->tstamp = p->timestamp;
1728 			pp->data[0] = p->header[1];
1729 			pp->data[1] = p->header[2];
1730 			queue_event(client, &e->event, &e->phy_packet, sizeof(*pp) + 8, NULL, 0);
1731 		}
1732 	}
1733 }
1734 
1735 static int (* const ioctl_handlers[])(struct client *, union ioctl_arg *) = {
1736 	[0x00] = ioctl_get_info,
1737 	[0x01] = ioctl_send_request,
1738 	[0x02] = ioctl_allocate,
1739 	[0x03] = ioctl_deallocate,
1740 	[0x04] = ioctl_send_response,
1741 	[0x05] = ioctl_initiate_bus_reset,
1742 	[0x06] = ioctl_add_descriptor,
1743 	[0x07] = ioctl_remove_descriptor,
1744 	[0x08] = ioctl_create_iso_context,
1745 	[0x09] = ioctl_queue_iso,
1746 	[0x0a] = ioctl_start_iso,
1747 	[0x0b] = ioctl_stop_iso,
1748 	[0x0c] = ioctl_get_cycle_timer,
1749 	[0x0d] = ioctl_allocate_iso_resource,
1750 	[0x0e] = ioctl_deallocate_iso_resource,
1751 	[0x0f] = ioctl_allocate_iso_resource_once,
1752 	[0x10] = ioctl_deallocate_iso_resource_once,
1753 	[0x11] = ioctl_get_speed,
1754 	[0x12] = ioctl_send_broadcast_request,
1755 	[0x13] = ioctl_send_stream_packet,
1756 	[0x14] = ioctl_get_cycle_timer2,
1757 	[0x15] = ioctl_send_phy_packet,
1758 	[0x16] = ioctl_receive_phy_packets,
1759 	[0x17] = ioctl_set_iso_channels,
1760 	[0x18] = ioctl_flush_iso,
1761 };
1762 
1763 static int dispatch_ioctl(struct client *client,
1764 			  unsigned int cmd, void __user *arg)
1765 {
1766 	union ioctl_arg buffer;
1767 	int ret;
1768 
1769 	if (fw_device_is_shutdown(client->device))
1770 		return -ENODEV;
1771 
1772 	if (_IOC_TYPE(cmd) != '#' ||
1773 	    _IOC_NR(cmd) >= ARRAY_SIZE(ioctl_handlers) ||
1774 	    _IOC_SIZE(cmd) > sizeof(buffer))
1775 		return -ENOTTY;
1776 
1777 	memset(&buffer, 0, sizeof(buffer));
1778 
1779 	if (_IOC_DIR(cmd) & _IOC_WRITE)
1780 		if (copy_from_user(&buffer, arg, _IOC_SIZE(cmd)))
1781 			return -EFAULT;
1782 
1783 	ret = ioctl_handlers[_IOC_NR(cmd)](client, &buffer);
1784 	if (ret < 0)
1785 		return ret;
1786 
1787 	if (_IOC_DIR(cmd) & _IOC_READ)
1788 		if (copy_to_user(arg, &buffer, _IOC_SIZE(cmd)))
1789 			return -EFAULT;
1790 
1791 	return ret;
1792 }
1793 
1794 static long fw_device_op_ioctl(struct file *file,
1795 			       unsigned int cmd, unsigned long arg)
1796 {
1797 	return dispatch_ioctl(file->private_data, cmd, (void __user *)arg);
1798 }
1799 
1800 static int fw_device_op_mmap(struct file *file, struct vm_area_struct *vma)
1801 {
1802 	struct client *client = file->private_data;
1803 	unsigned long size;
1804 	int page_count, ret;
1805 
1806 	if (fw_device_is_shutdown(client->device))
1807 		return -ENODEV;
1808 
1809 	/* FIXME: We could support multiple buffers, but we don't. */
1810 	if (client->buffer.pages != NULL)
1811 		return -EBUSY;
1812 
1813 	if (!(vma->vm_flags & VM_SHARED))
1814 		return -EINVAL;
1815 
1816 	if (vma->vm_start & ~PAGE_MASK)
1817 		return -EINVAL;
1818 
1819 	client->vm_start = vma->vm_start;
1820 	size = vma->vm_end - vma->vm_start;
1821 	page_count = size >> PAGE_SHIFT;
1822 	if (size & ~PAGE_MASK)
1823 		return -EINVAL;
1824 
1825 	ret = fw_iso_buffer_alloc(&client->buffer, page_count);
1826 	if (ret < 0)
1827 		return ret;
1828 
1829 	scoped_guard(spinlock_irq, &client->lock) {
1830 		if (client->iso_context) {
1831 			ret = fw_iso_buffer_map_dma(&client->buffer, client->device->card,
1832 						    iso_dma_direction(client->iso_context));
1833 			if (ret < 0)
1834 				goto fail;
1835 			client->buffer_is_mapped = true;
1836 		}
1837 	}
1838 
1839 	ret = vm_map_pages_zero(vma, client->buffer.pages,
1840 				client->buffer.page_count);
1841 	if (ret < 0)
1842 		goto fail;
1843 
1844 	return 0;
1845  fail:
1846 	fw_iso_buffer_destroy(&client->buffer, client->device->card);
1847 	return ret;
1848 }
1849 
1850 static bool has_outbound_transactions(struct client *client)
1851 {
1852 	struct client_resource *resource;
1853 	unsigned long index;
1854 
1855 	guard(spinlock_irq)(&client->lock);
1856 
1857 	xa_for_each(&client->resource_xa, index, resource) {
1858 		if (is_outbound_transaction_resource(resource))
1859 			return true;
1860 	}
1861 
1862 	return false;
1863 }
1864 
1865 static int fw_device_op_release(struct inode *inode, struct file *file)
1866 {
1867 	struct client *client = file->private_data;
1868 	struct event *event, *next_event;
1869 	struct client_resource *resource;
1870 	unsigned long index;
1871 
1872 	// NOTE: This can be without irq when we can guarantee that __fw_send_request() for local
1873 	// destination never runs in any type of IRQ context.
1874 	scoped_guard(spinlock_irq, &phy_receiver_list_lock)
1875 		list_del(&client->phy_receiver_link);
1876 
1877 	scoped_guard(mutex, &client->device->client_list_mutex)
1878 		list_del(&client->link);
1879 
1880 	if (client->iso_context)
1881 		fw_iso_context_destroy(client->iso_context);
1882 
1883 	if (client->buffer.pages)
1884 		fw_iso_buffer_destroy(&client->buffer, client->device->card);
1885 
1886 	// Freeze client->resource_xa and client->event_list.
1887 	scoped_guard(spinlock_irq, &client->lock)
1888 		client->in_shutdown = true;
1889 
1890 	wait_event(client->tx_flush_wait, !has_outbound_transactions(client));
1891 
1892 	xa_for_each(&client->resource_xa, index, resource) {
1893 		resource->release(client, resource);
1894 		client_put(client);
1895 	}
1896 	xa_destroy(&client->resource_xa);
1897 
1898 	list_for_each_entry_safe(event, next_event, &client->event_list, link)
1899 		kfree(event);
1900 
1901 	client_put(client);
1902 
1903 	return 0;
1904 }
1905 
1906 static __poll_t fw_device_op_poll(struct file *file, poll_table * pt)
1907 {
1908 	struct client *client = file->private_data;
1909 	__poll_t mask = 0;
1910 
1911 	poll_wait(file, &client->wait, pt);
1912 
1913 	if (fw_device_is_shutdown(client->device))
1914 		mask |= EPOLLHUP | EPOLLERR;
1915 	if (!list_empty(&client->event_list))
1916 		mask |= EPOLLIN | EPOLLRDNORM;
1917 
1918 	return mask;
1919 }
1920 
1921 const struct file_operations fw_device_ops = {
1922 	.owner		= THIS_MODULE,
1923 	.open		= fw_device_op_open,
1924 	.read		= fw_device_op_read,
1925 	.unlocked_ioctl	= fw_device_op_ioctl,
1926 	.mmap		= fw_device_op_mmap,
1927 	.release	= fw_device_op_release,
1928 	.poll		= fw_device_op_poll,
1929 	.compat_ioctl	= compat_ptr_ioctl,
1930 };
1931