1/*
2 * AGPGART driver frontend
3 * Copyright (C) 2004 Silicon Graphics, Inc.
4 * Copyright (C) 2002-2003 Dave Jones
5 * Copyright (C) 1999 Jeff Hartmann
6 * Copyright (C) 1999 Precision Insight, Inc.
7 * Copyright (C) 1999 Xi Graphics, Inc.
8 *
9 * Permission is hereby granted, free of charge, to any person obtaining a
10 * copy of this software and associated documentation files (the "Software"),
11 * to deal in the Software without restriction, including without limitation
12 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
13 * and/or sell copies of the Software, and to permit persons to whom the
14 * Software is furnished to do so, subject to the following conditions:
15 *
16 * The above copyright notice and this permission notice shall be included
17 * in all copies or substantial portions of the Software.
18 *
19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
20 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
22 * JEFF HARTMANN, OR ANY OTHER CONTRIBUTORS BE LIABLE FOR ANY CLAIM,
23 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
24 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
25 * OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
26 *
27 */
28
29#include <linux/types.h>
30#include <linux/kernel.h>
31#include <linux/module.h>
32#include <linux/mman.h>
33#include <linux/pci.h>
34#include <linux/miscdevice.h>
35#include <linux/agp_backend.h>
36#include <linux/agpgart.h>
37#include <linux/slab.h>
38#include <linux/mm.h>
39#include <linux/fs.h>
40#include <linux/sched.h>
41#include <linux/uaccess.h>
42#include "agp.h"
43
44struct agp_front_data agp_fe;
45
46struct agp_memory *agp_find_mem_by_key(int key)
47{
48	struct agp_memory *curr;
49
50	if (agp_fe.current_controller == NULL)
51		return NULL;
52
53	curr = agp_fe.current_controller->pool;
54
55	while (curr != NULL) {
56		if (curr->key == key)
57			break;
58		curr = curr->next;
59	}
60
61	DBG("key=%d -> mem=%p", key, curr);
62	return curr;
63}
64
65static void agp_remove_from_pool(struct agp_memory *temp)
66{
67	struct agp_memory *prev;
68	struct agp_memory *next;
69
70	/* Check to see if this is even in the memory pool */
71
72	DBG("mem=%p", temp);
73	if (agp_find_mem_by_key(temp->key) != NULL) {
74		next = temp->next;
75		prev = temp->prev;
76
77		if (prev != NULL) {
78			prev->next = next;
79			if (next != NULL)
80				next->prev = prev;
81
82		} else {
83			/* This is the first item on the list */
84			if (next != NULL)
85				next->prev = NULL;
86
87			agp_fe.current_controller->pool = next;
88		}
89	}
90}
91
92/*
93 * Routines for managing each client's segment list -
94 * These routines handle adding and removing segments
95 * to each auth'ed client.
96 */
97
98static struct
99agp_segment_priv *agp_find_seg_in_client(const struct agp_client *client,
100						unsigned long offset,
101					    int size, pgprot_t page_prot)
102{
103	struct agp_segment_priv *seg;
104	int i;
105	off_t pg_start;
106	size_t pg_count;
107
108	pg_start = offset / 4096;
109	pg_count = size / 4096;
110	seg = *(client->segments);
111
112	for (i = 0; i < client->num_segments; i++) {
113		if ((seg[i].pg_start == pg_start) &&
114		    (seg[i].pg_count == pg_count) &&
115		    (pgprot_val(seg[i].prot) == pgprot_val(page_prot))) {
116			return seg + i;
117		}
118	}
119
120	return NULL;
121}
122
123static void agp_remove_seg_from_client(struct agp_client *client)
124{
125	DBG("client=%p", client);
126
127	if (client->segments != NULL) {
128		if (*(client->segments) != NULL) {
129			DBG("Freeing %p from client %p", *(client->segments), client);
130			kfree(*(client->segments));
131		}
132		DBG("Freeing %p from client %p", client->segments, client);
133		kfree(client->segments);
134		client->segments = NULL;
135	}
136}
137
138static void agp_add_seg_to_client(struct agp_client *client,
139			       struct agp_segment_priv ** seg, int num_segments)
140{
141	struct agp_segment_priv **prev_seg;
142
143	prev_seg = client->segments;
144
145	if (prev_seg != NULL)
146		agp_remove_seg_from_client(client);
147
148	DBG("Adding seg %p (%d segments) to client %p", seg, num_segments, client);
149	client->num_segments = num_segments;
150	client->segments = seg;
151}
152
153static pgprot_t agp_convert_mmap_flags(int prot)
154{
155	unsigned long prot_bits;
156
157	prot_bits = calc_vm_prot_bits(prot, 0) | VM_SHARED;
158	return vm_get_page_prot(prot_bits);
159}
160
161int agp_create_segment(struct agp_client *client, struct agp_region *region)
162{
163	struct agp_segment_priv **ret_seg;
164	struct agp_segment_priv *seg;
165	struct agp_segment *user_seg;
166	size_t i;
167
168	seg = kzalloc((sizeof(struct agp_segment_priv) * region->seg_count), GFP_KERNEL);
169	if (seg == NULL) {
170		kfree(region->seg_list);
171		region->seg_list = NULL;
172		return -ENOMEM;
173	}
174	user_seg = region->seg_list;
175
176	for (i = 0; i < region->seg_count; i++) {
177		seg[i].pg_start = user_seg[i].pg_start;
178		seg[i].pg_count = user_seg[i].pg_count;
179		seg[i].prot = agp_convert_mmap_flags(user_seg[i].prot);
180	}
181	kfree(region->seg_list);
182	region->seg_list = NULL;
183
184	ret_seg = kmalloc(sizeof(void *), GFP_KERNEL);
185	if (ret_seg == NULL) {
186		kfree(seg);
187		return -ENOMEM;
188	}
189	*ret_seg = seg;
190	agp_add_seg_to_client(client, ret_seg, region->seg_count);
191	return 0;
192}
193
194/* End - Routines for managing each client's segment list */
195
196/* This function must only be called when current_controller != NULL */
197static void agp_insert_into_pool(struct agp_memory * temp)
198{
199	struct agp_memory *prev;
200
201	prev = agp_fe.current_controller->pool;
202
203	if (prev != NULL) {
204		prev->prev = temp;
205		temp->next = prev;
206	}
207	agp_fe.current_controller->pool = temp;
208}
209
210
211/* File private list routines */
212
213struct agp_file_private *agp_find_private(pid_t pid)
214{
215	struct agp_file_private *curr;
216
217	curr = agp_fe.file_priv_list;
218
219	while (curr != NULL) {
220		if (curr->my_pid == pid)
221			return curr;
222		curr = curr->next;
223	}
224
225	return NULL;
226}
227
228static void agp_insert_file_private(struct agp_file_private * priv)
229{
230	struct agp_file_private *prev;
231
232	prev = agp_fe.file_priv_list;
233
234	if (prev != NULL)
235		prev->prev = priv;
236	priv->next = prev;
237	agp_fe.file_priv_list = priv;
238}
239
240static void agp_remove_file_private(struct agp_file_private * priv)
241{
242	struct agp_file_private *next;
243	struct agp_file_private *prev;
244
245	next = priv->next;
246	prev = priv->prev;
247
248	if (prev != NULL) {
249		prev->next = next;
250
251		if (next != NULL)
252			next->prev = prev;
253
254	} else {
255		if (next != NULL)
256			next->prev = NULL;
257
258		agp_fe.file_priv_list = next;
259	}
260}
261
262/* End - File flag list routines */
263
264/*
265 * Wrappers for agp_free_memory & agp_allocate_memory
266 * These make sure that internal lists are kept updated.
267 */
268void agp_free_memory_wrap(struct agp_memory *memory)
269{
270	agp_remove_from_pool(memory);
271	agp_free_memory(memory);
272}
273
274struct agp_memory *agp_allocate_memory_wrap(size_t pg_count, u32 type)
275{
276	struct agp_memory *memory;
277
278	memory = agp_allocate_memory(agp_bridge, pg_count, type);
279	if (memory == NULL)
280		return NULL;
281
282	agp_insert_into_pool(memory);
283	return memory;
284}
285
286/* Routines for managing the list of controllers -
287 * These routines manage the current controller, and the list of
288 * controllers
289 */
290
291static struct agp_controller *agp_find_controller_by_pid(pid_t id)
292{
293	struct agp_controller *controller;
294
295	controller = agp_fe.controllers;
296
297	while (controller != NULL) {
298		if (controller->pid == id)
299			return controller;
300		controller = controller->next;
301	}
302
303	return NULL;
304}
305
306static struct agp_controller *agp_create_controller(pid_t id)
307{
308	struct agp_controller *controller;
309
310	controller = kzalloc(sizeof(struct agp_controller), GFP_KERNEL);
311	if (controller == NULL)
312		return NULL;
313
314	controller->pid = id;
315	return controller;
316}
317
318static int agp_insert_controller(struct agp_controller *controller)
319{
320	struct agp_controller *prev_controller;
321
322	prev_controller = agp_fe.controllers;
323	controller->next = prev_controller;
324
325	if (prev_controller != NULL)
326		prev_controller->prev = controller;
327
328	agp_fe.controllers = controller;
329
330	return 0;
331}
332
333static void agp_remove_all_clients(struct agp_controller *controller)
334{
335	struct agp_client *client;
336	struct agp_client *temp;
337
338	client = controller->clients;
339
340	while (client) {
341		struct agp_file_private *priv;
342
343		temp = client;
344		agp_remove_seg_from_client(temp);
345		priv = agp_find_private(temp->pid);
346
347		if (priv != NULL) {
348			clear_bit(AGP_FF_IS_VALID, &priv->access_flags);
349			clear_bit(AGP_FF_IS_CLIENT, &priv->access_flags);
350		}
351		client = client->next;
352		kfree(temp);
353	}
354}
355
356static void agp_remove_all_memory(struct agp_controller *controller)
357{
358	struct agp_memory *memory;
359	struct agp_memory *temp;
360
361	memory = controller->pool;
362
363	while (memory) {
364		temp = memory;
365		memory = memory->next;
366		agp_free_memory_wrap(temp);
367	}
368}
369
370static int agp_remove_controller(struct agp_controller *controller)
371{
372	struct agp_controller *prev_controller;
373	struct agp_controller *next_controller;
374
375	prev_controller = controller->prev;
376	next_controller = controller->next;
377
378	if (prev_controller != NULL) {
379		prev_controller->next = next_controller;
380		if (next_controller != NULL)
381			next_controller->prev = prev_controller;
382
383	} else {
384		if (next_controller != NULL)
385			next_controller->prev = NULL;
386
387		agp_fe.controllers = next_controller;
388	}
389
390	agp_remove_all_memory(controller);
391	agp_remove_all_clients(controller);
392
393	if (agp_fe.current_controller == controller) {
394		agp_fe.current_controller = NULL;
395		agp_fe.backend_acquired = false;
396		agp_backend_release(agp_bridge);
397	}
398	kfree(controller);
399	return 0;
400}
401
402static void agp_controller_make_current(struct agp_controller *controller)
403{
404	struct agp_client *clients;
405
406	clients = controller->clients;
407
408	while (clients != NULL) {
409		struct agp_file_private *priv;
410
411		priv = agp_find_private(clients->pid);
412
413		if (priv != NULL) {
414			set_bit(AGP_FF_IS_VALID, &priv->access_flags);
415			set_bit(AGP_FF_IS_CLIENT, &priv->access_flags);
416		}
417		clients = clients->next;
418	}
419
420	agp_fe.current_controller = controller;
421}
422
423static void agp_controller_release_current(struct agp_controller *controller,
424				      struct agp_file_private *controller_priv)
425{
426	struct agp_client *clients;
427
428	clear_bit(AGP_FF_IS_VALID, &controller_priv->access_flags);
429	clients = controller->clients;
430
431	while (clients != NULL) {
432		struct agp_file_private *priv;
433
434		priv = agp_find_private(clients->pid);
435
436		if (priv != NULL)
437			clear_bit(AGP_FF_IS_VALID, &priv->access_flags);
438
439		clients = clients->next;
440	}
441
442	agp_fe.current_controller = NULL;
443	agp_fe.used_by_controller = false;
444	agp_backend_release(agp_bridge);
445}
446
447/*
448 * Routines for managing client lists -
449 * These routines are for managing the list of auth'ed clients.
450 */
451
452static struct agp_client
453*agp_find_client_in_controller(struct agp_controller *controller, pid_t id)
454{
455	struct agp_client *client;
456
457	if (controller == NULL)
458		return NULL;
459
460	client = controller->clients;
461
462	while (client != NULL) {
463		if (client->pid == id)
464			return client;
465		client = client->next;
466	}
467
468	return NULL;
469}
470
471static struct agp_controller *agp_find_controller_for_client(pid_t id)
472{
473	struct agp_controller *controller;
474
475	controller = agp_fe.controllers;
476
477	while (controller != NULL) {
478		if ((agp_find_client_in_controller(controller, id)) != NULL)
479			return controller;
480		controller = controller->next;
481	}
482
483	return NULL;
484}
485
486struct agp_client *agp_find_client_by_pid(pid_t id)
487{
488	struct agp_client *temp;
489
490	if (agp_fe.current_controller == NULL)
491		return NULL;
492
493	temp = agp_find_client_in_controller(agp_fe.current_controller, id);
494	return temp;
495}
496
497static void agp_insert_client(struct agp_client *client)
498{
499	struct agp_client *prev_client;
500
501	prev_client = agp_fe.current_controller->clients;
502	client->next = prev_client;
503
504	if (prev_client != NULL)
505		prev_client->prev = client;
506
507	agp_fe.current_controller->clients = client;
508	agp_fe.current_controller->num_clients++;
509}
510
511struct agp_client *agp_create_client(pid_t id)
512{
513	struct agp_client *new_client;
514
515	new_client = kzalloc(sizeof(struct agp_client), GFP_KERNEL);
516	if (new_client == NULL)
517		return NULL;
518
519	new_client->pid = id;
520	agp_insert_client(new_client);
521	return new_client;
522}
523
524int agp_remove_client(pid_t id)
525{
526	struct agp_client *client;
527	struct agp_client *prev_client;
528	struct agp_client *next_client;
529	struct agp_controller *controller;
530
531	controller = agp_find_controller_for_client(id);
532	if (controller == NULL)
533		return -EINVAL;
534
535	client = agp_find_client_in_controller(controller, id);
536	if (client == NULL)
537		return -EINVAL;
538
539	prev_client = client->prev;
540	next_client = client->next;
541
542	if (prev_client != NULL) {
543		prev_client->next = next_client;
544		if (next_client != NULL)
545			next_client->prev = prev_client;
546
547	} else {
548		if (next_client != NULL)
549			next_client->prev = NULL;
550		controller->clients = next_client;
551	}
552
553	controller->num_clients--;
554	agp_remove_seg_from_client(client);
555	kfree(client);
556	return 0;
557}
558
559/* End - Routines for managing client lists */
560
561/* File Operations */
562
563static int agp_mmap(struct file *file, struct vm_area_struct *vma)
564{
565	unsigned int size, current_size;
566	unsigned long offset;
567	struct agp_client *client;
568	struct agp_file_private *priv = file->private_data;
569	struct agp_kern_info kerninfo;
570
571	mutex_lock(&(agp_fe.agp_mutex));
572
573	if (agp_fe.backend_acquired != true)
574		goto out_eperm;
575
576	if (!(test_bit(AGP_FF_IS_VALID, &priv->access_flags)))
577		goto out_eperm;
578
579	agp_copy_info(agp_bridge, &kerninfo);
580	size = vma->vm_end - vma->vm_start;
581	current_size = kerninfo.aper_size;
582	current_size = current_size * 0x100000;
583	offset = vma->vm_pgoff << PAGE_SHIFT;
584	DBG("%lx:%lx", offset, offset+size);
585
586	if (test_bit(AGP_FF_IS_CLIENT, &priv->access_flags)) {
587		if ((size + offset) > current_size)
588			goto out_inval;
589
590		client = agp_find_client_by_pid(current->pid);
591
592		if (client == NULL)
593			goto out_eperm;
594
595		if (!agp_find_seg_in_client(client, offset, size, vma->vm_page_prot))
596			goto out_inval;
597
598		DBG("client vm_ops=%p", kerninfo.vm_ops);
599		if (kerninfo.vm_ops) {
600			vma->vm_ops = kerninfo.vm_ops;
601		} else if (io_remap_pfn_range(vma, vma->vm_start,
602				(kerninfo.aper_base + offset) >> PAGE_SHIFT,
603				size,
604				pgprot_writecombine(vma->vm_page_prot))) {
605			goto out_again;
606		}
607		mutex_unlock(&(agp_fe.agp_mutex));
608		return 0;
609	}
610
611	if (test_bit(AGP_FF_IS_CONTROLLER, &priv->access_flags)) {
612		if (size != current_size)
613			goto out_inval;
614
615		DBG("controller vm_ops=%p", kerninfo.vm_ops);
616		if (kerninfo.vm_ops) {
617			vma->vm_ops = kerninfo.vm_ops;
618		} else if (io_remap_pfn_range(vma, vma->vm_start,
619				kerninfo.aper_base >> PAGE_SHIFT,
620				size,
621				pgprot_writecombine(vma->vm_page_prot))) {
622			goto out_again;
623		}
624		mutex_unlock(&(agp_fe.agp_mutex));
625		return 0;
626	}
627
628out_eperm:
629	mutex_unlock(&(agp_fe.agp_mutex));
630	return -EPERM;
631
632out_inval:
633	mutex_unlock(&(agp_fe.agp_mutex));
634	return -EINVAL;
635
636out_again:
637	mutex_unlock(&(agp_fe.agp_mutex));
638	return -EAGAIN;
639}
640
641static int agp_release(struct inode *inode, struct file *file)
642{
643	struct agp_file_private *priv = file->private_data;
644
645	mutex_lock(&(agp_fe.agp_mutex));
646
647	DBG("priv=%p", priv);
648
649	if (test_bit(AGP_FF_IS_CONTROLLER, &priv->access_flags)) {
650		struct agp_controller *controller;
651
652		controller = agp_find_controller_by_pid(priv->my_pid);
653
654		if (controller != NULL) {
655			if (controller == agp_fe.current_controller)
656				agp_controller_release_current(controller, priv);
657			agp_remove_controller(controller);
658			controller = NULL;
659		}
660	}
661
662	if (test_bit(AGP_FF_IS_CLIENT, &priv->access_flags))
663		agp_remove_client(priv->my_pid);
664
665	agp_remove_file_private(priv);
666	kfree(priv);
667	file->private_data = NULL;
668	mutex_unlock(&(agp_fe.agp_mutex));
669	return 0;
670}
671
672static int agp_open(struct inode *inode, struct file *file)
673{
674	int minor = iminor(inode);
675	struct agp_file_private *priv;
676	struct agp_client *client;
677
678	if (minor != AGPGART_MINOR)
679		return -ENXIO;
680
681	mutex_lock(&(agp_fe.agp_mutex));
682
683	priv = kzalloc(sizeof(struct agp_file_private), GFP_KERNEL);
684	if (priv == NULL) {
685		mutex_unlock(&(agp_fe.agp_mutex));
686		return -ENOMEM;
687	}
688
689	set_bit(AGP_FF_ALLOW_CLIENT, &priv->access_flags);
690	priv->my_pid = current->pid;
691
692	if (capable(CAP_SYS_RAWIO))
693		/* Root priv, can be controller */
694		set_bit(AGP_FF_ALLOW_CONTROLLER, &priv->access_flags);
695
696	client = agp_find_client_by_pid(current->pid);
697
698	if (client != NULL) {
699		set_bit(AGP_FF_IS_CLIENT, &priv->access_flags);
700		set_bit(AGP_FF_IS_VALID, &priv->access_flags);
701	}
702	file->private_data = (void *) priv;
703	agp_insert_file_private(priv);
704	DBG("private=%p, client=%p", priv, client);
705
706	mutex_unlock(&(agp_fe.agp_mutex));
707
708	return 0;
709}
710
711static int agpioc_info_wrap(struct agp_file_private *priv, void __user *arg)
712{
713	struct agp_info userinfo;
714	struct agp_kern_info kerninfo;
715
716	agp_copy_info(agp_bridge, &kerninfo);
717
718	memset(&userinfo, 0, sizeof(userinfo));
719	userinfo.version.major = kerninfo.version.major;
720	userinfo.version.minor = kerninfo.version.minor;
721	userinfo.bridge_id = kerninfo.device->vendor |
722	    (kerninfo.device->device << 16);
723	userinfo.agp_mode = kerninfo.mode;
724	userinfo.aper_base = kerninfo.aper_base;
725	userinfo.aper_size = kerninfo.aper_size;
726	userinfo.pg_total = userinfo.pg_system = kerninfo.max_memory;
727	userinfo.pg_used = kerninfo.current_memory;
728
729	if (copy_to_user(arg, &userinfo, sizeof(struct agp_info)))
730		return -EFAULT;
731
732	return 0;
733}
734
735int agpioc_acquire_wrap(struct agp_file_private *priv)
736{
737	struct agp_controller *controller;
738
739	DBG("");
740
741	if (!(test_bit(AGP_FF_ALLOW_CONTROLLER, &priv->access_flags)))
742		return -EPERM;
743
744	if (agp_fe.current_controller != NULL)
745		return -EBUSY;
746
747	if (!agp_bridge)
748		return -ENODEV;
749
750        if (atomic_read(&agp_bridge->agp_in_use))
751                return -EBUSY;
752
753	atomic_inc(&agp_bridge->agp_in_use);
754
755	agp_fe.backend_acquired = true;
756
757	controller = agp_find_controller_by_pid(priv->my_pid);
758
759	if (controller != NULL) {
760		agp_controller_make_current(controller);
761	} else {
762		controller = agp_create_controller(priv->my_pid);
763
764		if (controller == NULL) {
765			agp_fe.backend_acquired = false;
766			agp_backend_release(agp_bridge);
767			return -ENOMEM;
768		}
769		agp_insert_controller(controller);
770		agp_controller_make_current(controller);
771	}
772
773	set_bit(AGP_FF_IS_CONTROLLER, &priv->access_flags);
774	set_bit(AGP_FF_IS_VALID, &priv->access_flags);
775	return 0;
776}
777
778int agpioc_release_wrap(struct agp_file_private *priv)
779{
780	DBG("");
781	agp_controller_release_current(agp_fe.current_controller, priv);
782	return 0;
783}
784
785int agpioc_setup_wrap(struct agp_file_private *priv, void __user *arg)
786{
787	struct agp_setup mode;
788
789	DBG("");
790	if (copy_from_user(&mode, arg, sizeof(struct agp_setup)))
791		return -EFAULT;
792
793	agp_enable(agp_bridge, mode.agp_mode);
794	return 0;
795}
796
797static int agpioc_reserve_wrap(struct agp_file_private *priv, void __user *arg)
798{
799	struct agp_region reserve;
800	struct agp_client *client;
801	struct agp_file_private *client_priv;
802
803	DBG("");
804	if (copy_from_user(&reserve, arg, sizeof(struct agp_region)))
805		return -EFAULT;
806
807	if ((unsigned) reserve.seg_count >= ~0U/sizeof(struct agp_segment))
808		return -EFAULT;
809
810	client = agp_find_client_by_pid(reserve.pid);
811
812	if (reserve.seg_count == 0) {
813		/* remove a client */
814		client_priv = agp_find_private(reserve.pid);
815
816		if (client_priv != NULL) {
817			set_bit(AGP_FF_IS_CLIENT, &client_priv->access_flags);
818			set_bit(AGP_FF_IS_VALID, &client_priv->access_flags);
819		}
820		if (client == NULL) {
821			/* client is already removed */
822			return 0;
823		}
824		return agp_remove_client(reserve.pid);
825	} else {
826		struct agp_segment *segment;
827
828		if (reserve.seg_count >= 16384)
829			return -EINVAL;
830
831		segment = kmalloc((sizeof(struct agp_segment) * reserve.seg_count),
832				  GFP_KERNEL);
833
834		if (segment == NULL)
835			return -ENOMEM;
836
837		if (copy_from_user(segment, (void __user *) reserve.seg_list,
838				   sizeof(struct agp_segment) * reserve.seg_count)) {
839			kfree(segment);
840			return -EFAULT;
841		}
842		reserve.seg_list = segment;
843
844		if (client == NULL) {
845			/* Create the client and add the segment */
846			client = agp_create_client(reserve.pid);
847
848			if (client == NULL) {
849				kfree(segment);
850				return -ENOMEM;
851			}
852			client_priv = agp_find_private(reserve.pid);
853
854			if (client_priv != NULL) {
855				set_bit(AGP_FF_IS_CLIENT, &client_priv->access_flags);
856				set_bit(AGP_FF_IS_VALID, &client_priv->access_flags);
857			}
858		}
859		return agp_create_segment(client, &reserve);
860	}
861	/* Will never really happen */
862	return -EINVAL;
863}
864
865int agpioc_protect_wrap(struct agp_file_private *priv)
866{
867	DBG("");
868	/* This function is not currently implemented */
869	return -EINVAL;
870}
871
872static int agpioc_allocate_wrap(struct agp_file_private *priv, void __user *arg)
873{
874	struct agp_memory *memory;
875	struct agp_allocate alloc;
876
877	DBG("");
878	if (copy_from_user(&alloc, arg, sizeof(struct agp_allocate)))
879		return -EFAULT;
880
881	if (alloc.type >= AGP_USER_TYPES)
882		return -EINVAL;
883
884	memory = agp_allocate_memory_wrap(alloc.pg_count, alloc.type);
885
886	if (memory == NULL)
887		return -ENOMEM;
888
889	alloc.key = memory->key;
890	alloc.physical = memory->physical;
891
892	if (copy_to_user(arg, &alloc, sizeof(struct agp_allocate))) {
893		agp_free_memory_wrap(memory);
894		return -EFAULT;
895	}
896	return 0;
897}
898
899int agpioc_deallocate_wrap(struct agp_file_private *priv, int arg)
900{
901	struct agp_memory *memory;
902
903	DBG("");
904	memory = agp_find_mem_by_key(arg);
905
906	if (memory == NULL)
907		return -EINVAL;
908
909	agp_free_memory_wrap(memory);
910	return 0;
911}
912
913static int agpioc_bind_wrap(struct agp_file_private *priv, void __user *arg)
914{
915	struct agp_bind bind_info;
916	struct agp_memory *memory;
917
918	DBG("");
919	if (copy_from_user(&bind_info, arg, sizeof(struct agp_bind)))
920		return -EFAULT;
921
922	memory = agp_find_mem_by_key(bind_info.key);
923
924	if (memory == NULL)
925		return -EINVAL;
926
927	return agp_bind_memory(memory, bind_info.pg_start);
928}
929
930static int agpioc_unbind_wrap(struct agp_file_private *priv, void __user *arg)
931{
932	struct agp_memory *memory;
933	struct agp_unbind unbind;
934
935	DBG("");
936	if (copy_from_user(&unbind, arg, sizeof(struct agp_unbind)))
937		return -EFAULT;
938
939	memory = agp_find_mem_by_key(unbind.key);
940
941	if (memory == NULL)
942		return -EINVAL;
943
944	return agp_unbind_memory(memory);
945}
946
947static long agp_ioctl(struct file *file,
948		     unsigned int cmd, unsigned long arg)
949{
950	struct agp_file_private *curr_priv = file->private_data;
951	int ret_val = -ENOTTY;
952
953	DBG("priv=%p, cmd=%x", curr_priv, cmd);
954	mutex_lock(&(agp_fe.agp_mutex));
955
956	if ((agp_fe.current_controller == NULL) &&
957	    (cmd != AGPIOC_ACQUIRE)) {
958		ret_val = -EINVAL;
959		goto ioctl_out;
960	}
961	if ((agp_fe.backend_acquired != true) &&
962	    (cmd != AGPIOC_ACQUIRE)) {
963		ret_val = -EBUSY;
964		goto ioctl_out;
965	}
966	if (cmd != AGPIOC_ACQUIRE) {
967		if (!(test_bit(AGP_FF_IS_CONTROLLER, &curr_priv->access_flags))) {
968			ret_val = -EPERM;
969			goto ioctl_out;
970		}
971		/* Use the original pid of the controller,
972		 * in case it's threaded */
973
974		if (agp_fe.current_controller->pid != curr_priv->my_pid) {
975			ret_val = -EBUSY;
976			goto ioctl_out;
977		}
978	}
979
980	switch (cmd) {
981	case AGPIOC_INFO:
982		ret_val = agpioc_info_wrap(curr_priv, (void __user *) arg);
983		break;
984
985	case AGPIOC_ACQUIRE:
986		ret_val = agpioc_acquire_wrap(curr_priv);
987		break;
988
989	case AGPIOC_RELEASE:
990		ret_val = agpioc_release_wrap(curr_priv);
991		break;
992
993	case AGPIOC_SETUP:
994		ret_val = agpioc_setup_wrap(curr_priv, (void __user *) arg);
995		break;
996
997	case AGPIOC_RESERVE:
998		ret_val = agpioc_reserve_wrap(curr_priv, (void __user *) arg);
999		break;
1000
1001	case AGPIOC_PROTECT:
1002		ret_val = agpioc_protect_wrap(curr_priv);
1003		break;
1004
1005	case AGPIOC_ALLOCATE:
1006		ret_val = agpioc_allocate_wrap(curr_priv, (void __user *) arg);
1007		break;
1008
1009	case AGPIOC_DEALLOCATE:
1010		ret_val = agpioc_deallocate_wrap(curr_priv, (int) arg);
1011		break;
1012
1013	case AGPIOC_BIND:
1014		ret_val = agpioc_bind_wrap(curr_priv, (void __user *) arg);
1015		break;
1016
1017	case AGPIOC_UNBIND:
1018		ret_val = agpioc_unbind_wrap(curr_priv, (void __user *) arg);
1019		break;
1020
1021	case AGPIOC_CHIPSET_FLUSH:
1022		break;
1023	}
1024
1025ioctl_out:
1026	DBG("ioctl returns %d\n", ret_val);
1027	mutex_unlock(&(agp_fe.agp_mutex));
1028	return ret_val;
1029}
1030
1031static const struct file_operations agp_fops =
1032{
1033	.owner		= THIS_MODULE,
1034	.llseek		= no_llseek,
1035	.unlocked_ioctl	= agp_ioctl,
1036#ifdef CONFIG_COMPAT
1037	.compat_ioctl	= compat_agp_ioctl,
1038#endif
1039	.mmap		= agp_mmap,
1040	.open		= agp_open,
1041	.release	= agp_release,
1042};
1043
1044static struct miscdevice agp_miscdev =
1045{
1046	.minor	= AGPGART_MINOR,
1047	.name	= "agpgart",
1048	.fops	= &agp_fops
1049};
1050
1051int agp_frontend_initialize(void)
1052{
1053	memset(&agp_fe, 0, sizeof(struct agp_front_data));
1054	mutex_init(&(agp_fe.agp_mutex));
1055
1056	if (misc_register(&agp_miscdev)) {
1057		printk(KERN_ERR PFX "unable to get minor: %d\n", AGPGART_MINOR);
1058		return -EIO;
1059	}
1060	return 0;
1061}
1062
1063void agp_frontend_cleanup(void)
1064{
1065	misc_deregister(&agp_miscdev);
1066}
1067