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/init.h>
35#include <linux/miscdevice.h>
36#include <linux/agp_backend.h>
37#include <linux/agpgart.h>
38#include <linux/slab.h>
39#include <linux/mm.h>
40#include <linux/fs.h>
41#include <linux/sched.h>
42#include <asm/uaccess.h>
43#include <asm/pgtable.h>
44#include "agp.h"
45
46struct agp_front_data agp_fe;
47
48struct agp_memory *agp_find_mem_by_key(int key)
49{
50	struct agp_memory *curr;
51
52	if (agp_fe.current_controller == NULL)
53		return NULL;
54
55	curr = agp_fe.current_controller->pool;
56
57	while (curr != NULL) {
58		if (curr->key == key)
59			break;
60		curr = curr->next;
61	}
62
63	DBG("key=%d -> mem=%p", key, curr);
64	return curr;
65}
66
67static void agp_remove_from_pool(struct agp_memory *temp)
68{
69	struct agp_memory *prev;
70	struct agp_memory *next;
71
72	/* Check to see if this is even in the memory pool */
73
74	DBG("mem=%p", temp);
75	if (agp_find_mem_by_key(temp->key) != NULL) {
76		next = temp->next;
77		prev = temp->prev;
78
79		if (prev != NULL) {
80			prev->next = next;
81			if (next != NULL)
82				next->prev = prev;
83
84		} else {
85			/* This is the first item on the list */
86			if (next != NULL)
87				next->prev = NULL;
88
89			agp_fe.current_controller->pool = next;
90		}
91	}
92}
93
94/*
95 * Routines for managing each client's segment list -
96 * These routines handle adding and removing segments
97 * to each auth'ed client.
98 */
99
100static struct
101agp_segment_priv *agp_find_seg_in_client(const struct agp_client *client,
102						unsigned long offset,
103					    int size, pgprot_t page_prot)
104{
105	struct agp_segment_priv *seg;
106	int num_segments, i;
107	off_t pg_start;
108	size_t pg_count;
109
110	pg_start = offset / 4096;
111	pg_count = size / 4096;
112	seg = *(client->segments);
113	num_segments = client->num_segments;
114
115	for (i = 0; i < client->num_segments; i++) {
116		if ((seg[i].pg_start == pg_start) &&
117		    (seg[i].pg_count == pg_count) &&
118		    (pgprot_val(seg[i].prot) == pgprot_val(page_prot))) {
119			return seg + i;
120		}
121	}
122
123	return NULL;
124}
125
126static void agp_remove_seg_from_client(struct agp_client *client)
127{
128	DBG("client=%p", client);
129
130	if (client->segments != NULL) {
131		if (*(client->segments) != NULL) {
132			DBG("Freeing %p from client %p", *(client->segments), client);
133			kfree(*(client->segments));
134		}
135		DBG("Freeing %p from client %p", client->segments, client);
136		kfree(client->segments);
137		client->segments = NULL;
138	}
139}
140
141static void agp_add_seg_to_client(struct agp_client *client,
142			       struct agp_segment_priv ** seg, int num_segments)
143{
144	struct agp_segment_priv **prev_seg;
145
146	prev_seg = client->segments;
147
148	if (prev_seg != NULL)
149		agp_remove_seg_from_client(client);
150
151	DBG("Adding seg %p (%d segments) to client %p", seg, num_segments, client);
152	client->num_segments = num_segments;
153	client->segments = seg;
154}
155
156static pgprot_t agp_convert_mmap_flags(int prot)
157{
158	unsigned long prot_bits;
159
160	prot_bits = calc_vm_prot_bits(prot) | VM_SHARED;
161	return vm_get_page_prot(prot_bits);
162}
163
164int agp_create_segment(struct agp_client *client, struct agp_region *region)
165{
166	struct agp_segment_priv **ret_seg;
167	struct agp_segment_priv *seg;
168	struct agp_segment *user_seg;
169	size_t i;
170
171	seg = kzalloc((sizeof(struct agp_segment_priv) * region->seg_count), GFP_KERNEL);
172	if (seg == NULL) {
173		kfree(region->seg_list);
174		region->seg_list = NULL;
175		return -ENOMEM;
176	}
177	user_seg = region->seg_list;
178
179	for (i = 0; i < region->seg_count; i++) {
180		seg[i].pg_start = user_seg[i].pg_start;
181		seg[i].pg_count = user_seg[i].pg_count;
182		seg[i].prot = agp_convert_mmap_flags(user_seg[i].prot);
183	}
184	kfree(region->seg_list);
185	region->seg_list = NULL;
186
187	ret_seg = kmalloc(sizeof(void *), GFP_KERNEL);
188	if (ret_seg == NULL) {
189		kfree(seg);
190		return -ENOMEM;
191	}
192	*ret_seg = seg;
193	agp_add_seg_to_client(client, ret_seg, region->seg_count);
194	return 0;
195}
196
197/* End - Routines for managing each client's segment list */
198
199/* This function must only be called when current_controller != NULL */
200static void agp_insert_into_pool(struct agp_memory * temp)
201{
202	struct agp_memory *prev;
203
204	prev = agp_fe.current_controller->pool;
205
206	if (prev != NULL) {
207		prev->prev = temp;
208		temp->next = prev;
209	}
210	agp_fe.current_controller->pool = temp;
211}
212
213
214/* File private list routines */
215
216struct agp_file_private *agp_find_private(pid_t pid)
217{
218	struct agp_file_private *curr;
219
220	curr = agp_fe.file_priv_list;
221
222	while (curr != NULL) {
223		if (curr->my_pid == pid)
224			return curr;
225		curr = curr->next;
226	}
227
228	return NULL;
229}
230
231static void agp_insert_file_private(struct agp_file_private * priv)
232{
233	struct agp_file_private *prev;
234
235	prev = agp_fe.file_priv_list;
236
237	if (prev != NULL)
238		prev->prev = priv;
239	priv->next = prev;
240	agp_fe.file_priv_list = priv;
241}
242
243static void agp_remove_file_private(struct agp_file_private * priv)
244{
245	struct agp_file_private *next;
246	struct agp_file_private *prev;
247
248	next = priv->next;
249	prev = priv->prev;
250
251	if (prev != NULL) {
252		prev->next = next;
253
254		if (next != NULL)
255			next->prev = prev;
256
257	} else {
258		if (next != NULL)
259			next->prev = NULL;
260
261		agp_fe.file_priv_list = next;
262	}
263}
264
265/* End - File flag list routines */
266
267/*
268 * Wrappers for agp_free_memory & agp_allocate_memory
269 * These make sure that internal lists are kept updated.
270 */
271void agp_free_memory_wrap(struct agp_memory *memory)
272{
273	agp_remove_from_pool(memory);
274	agp_free_memory(memory);
275}
276
277struct agp_memory *agp_allocate_memory_wrap(size_t pg_count, u32 type)
278{
279	struct agp_memory *memory;
280
281	memory = agp_allocate_memory(agp_bridge, pg_count, type);
282	if (memory == NULL)
283		return NULL;
284
285	agp_insert_into_pool(memory);
286	return memory;
287}
288
289/* Routines for managing the list of controllers -
290 * These routines manage the current controller, and the list of
291 * controllers
292 */
293
294static struct agp_controller *agp_find_controller_by_pid(pid_t id)
295{
296	struct agp_controller *controller;
297
298	controller = agp_fe.controllers;
299
300	while (controller != NULL) {
301		if (controller->pid == id)
302			return controller;
303		controller = controller->next;
304	}
305
306	return NULL;
307}
308
309static struct agp_controller *agp_create_controller(pid_t id)
310{
311	struct agp_controller *controller;
312
313	controller = kzalloc(sizeof(struct agp_controller), GFP_KERNEL);
314	if (controller == NULL)
315		return NULL;
316
317	controller->pid = id;
318	return controller;
319}
320
321static int agp_insert_controller(struct agp_controller *controller)
322{
323	struct agp_controller *prev_controller;
324
325	prev_controller = agp_fe.controllers;
326	controller->next = prev_controller;
327
328	if (prev_controller != NULL)
329		prev_controller->prev = controller;
330
331	agp_fe.controllers = controller;
332
333	return 0;
334}
335
336static void agp_remove_all_clients(struct agp_controller *controller)
337{
338	struct agp_client *client;
339	struct agp_client *temp;
340
341	client = controller->clients;
342
343	while (client) {
344		struct agp_file_private *priv;
345
346		temp = client;
347		agp_remove_seg_from_client(temp);
348		priv = agp_find_private(temp->pid);
349
350		if (priv != NULL) {
351			clear_bit(AGP_FF_IS_VALID, &priv->access_flags);
352			clear_bit(AGP_FF_IS_CLIENT, &priv->access_flags);
353		}
354		client = client->next;
355		kfree(temp);
356	}
357}
358
359static void agp_remove_all_memory(struct agp_controller *controller)
360{
361	struct agp_memory *memory;
362	struct agp_memory *temp;
363
364	memory = controller->pool;
365
366	while (memory) {
367		temp = memory;
368		memory = memory->next;
369		agp_free_memory_wrap(temp);
370	}
371}
372
373static int agp_remove_controller(struct agp_controller *controller)
374{
375	struct agp_controller *prev_controller;
376	struct agp_controller *next_controller;
377
378	prev_controller = controller->prev;
379	next_controller = controller->next;
380
381	if (prev_controller != NULL) {
382		prev_controller->next = next_controller;
383		if (next_controller != NULL)
384			next_controller->prev = prev_controller;
385
386	} else {
387		if (next_controller != NULL)
388			next_controller->prev = NULL;
389
390		agp_fe.controllers = next_controller;
391	}
392
393	agp_remove_all_memory(controller);
394	agp_remove_all_clients(controller);
395
396	if (agp_fe.current_controller == controller) {
397		agp_fe.current_controller = NULL;
398		agp_fe.backend_acquired = false;
399		agp_backend_release(agp_bridge);
400	}
401	kfree(controller);
402	return 0;
403}
404
405static void agp_controller_make_current(struct agp_controller *controller)
406{
407	struct agp_client *clients;
408
409	clients = controller->clients;
410
411	while (clients != NULL) {
412		struct agp_file_private *priv;
413
414		priv = agp_find_private(clients->pid);
415
416		if (priv != NULL) {
417			set_bit(AGP_FF_IS_VALID, &priv->access_flags);
418			set_bit(AGP_FF_IS_CLIENT, &priv->access_flags);
419		}
420		clients = clients->next;
421	}
422
423	agp_fe.current_controller = controller;
424}
425
426static void agp_controller_release_current(struct agp_controller *controller,
427				      struct agp_file_private *controller_priv)
428{
429	struct agp_client *clients;
430
431	clear_bit(AGP_FF_IS_VALID, &controller_priv->access_flags);
432	clients = controller->clients;
433
434	while (clients != NULL) {
435		struct agp_file_private *priv;
436
437		priv = agp_find_private(clients->pid);
438
439		if (priv != NULL)
440			clear_bit(AGP_FF_IS_VALID, &priv->access_flags);
441
442		clients = clients->next;
443	}
444
445	agp_fe.current_controller = NULL;
446	agp_fe.used_by_controller = false;
447	agp_backend_release(agp_bridge);
448}
449
450/*
451 * Routines for managing client lists -
452 * These routines are for managing the list of auth'ed clients.
453 */
454
455static struct agp_client
456*agp_find_client_in_controller(struct agp_controller *controller, pid_t id)
457{
458	struct agp_client *client;
459
460	if (controller == NULL)
461		return NULL;
462
463	client = controller->clients;
464
465	while (client != NULL) {
466		if (client->pid == id)
467			return client;
468		client = client->next;
469	}
470
471	return NULL;
472}
473
474static struct agp_controller *agp_find_controller_for_client(pid_t id)
475{
476	struct agp_controller *controller;
477
478	controller = agp_fe.controllers;
479
480	while (controller != NULL) {
481		if ((agp_find_client_in_controller(controller, id)) != NULL)
482			return controller;
483		controller = controller->next;
484	}
485
486	return NULL;
487}
488
489struct agp_client *agp_find_client_by_pid(pid_t id)
490{
491	struct agp_client *temp;
492
493	if (agp_fe.current_controller == NULL)
494		return NULL;
495
496	temp = agp_find_client_in_controller(agp_fe.current_controller, id);
497	return temp;
498}
499
500static void agp_insert_client(struct agp_client *client)
501{
502	struct agp_client *prev_client;
503
504	prev_client = agp_fe.current_controller->clients;
505	client->next = prev_client;
506
507	if (prev_client != NULL)
508		prev_client->prev = client;
509
510	agp_fe.current_controller->clients = client;
511	agp_fe.current_controller->num_clients++;
512}
513
514struct agp_client *agp_create_client(pid_t id)
515{
516	struct agp_client *new_client;
517
518	new_client = kzalloc(sizeof(struct agp_client), GFP_KERNEL);
519	if (new_client == NULL)
520		return NULL;
521
522	new_client->pid = id;
523	agp_insert_client(new_client);
524	return new_client;
525}
526
527int agp_remove_client(pid_t id)
528{
529	struct agp_client *client;
530	struct agp_client *prev_client;
531	struct agp_client *next_client;
532	struct agp_controller *controller;
533
534	controller = agp_find_controller_for_client(id);
535	if (controller == NULL)
536		return -EINVAL;
537
538	client = agp_find_client_in_controller(controller, id);
539	if (client == NULL)
540		return -EINVAL;
541
542	prev_client = client->prev;
543	next_client = client->next;
544
545	if (prev_client != NULL) {
546		prev_client->next = next_client;
547		if (next_client != NULL)
548			next_client->prev = prev_client;
549
550	} else {
551		if (next_client != NULL)
552			next_client->prev = NULL;
553		controller->clients = next_client;
554	}
555
556	controller->num_clients--;
557	agp_remove_seg_from_client(client);
558	kfree(client);
559	return 0;
560}
561
562/* End - Routines for managing client lists */
563
564/* File Operations */
565
566static int agp_mmap(struct file *file, struct vm_area_struct *vma)
567{
568	unsigned int size, current_size;
569	unsigned long offset;
570	struct agp_client *client;
571	struct agp_file_private *priv = file->private_data;
572	struct agp_kern_info kerninfo;
573
574	mutex_lock(&(agp_fe.agp_mutex));
575
576	if (agp_fe.backend_acquired != true)
577		goto out_eperm;
578
579	if (!(test_bit(AGP_FF_IS_VALID, &priv->access_flags)))
580		goto out_eperm;
581
582	agp_copy_info(agp_bridge, &kerninfo);
583	size = vma->vm_end - vma->vm_start;
584	current_size = kerninfo.aper_size;
585	current_size = current_size * 0x100000;
586	offset = vma->vm_pgoff << PAGE_SHIFT;
587	DBG("%lx:%lx", offset, offset+size);
588
589	if (test_bit(AGP_FF_IS_CLIENT, &priv->access_flags)) {
590		if ((size + offset) > current_size)
591			goto out_inval;
592
593		client = agp_find_client_by_pid(current->pid);
594
595		if (client == NULL)
596			goto out_eperm;
597
598		if (!agp_find_seg_in_client(client, offset, size, vma->vm_page_prot))
599			goto out_inval;
600
601		DBG("client vm_ops=%p", kerninfo.vm_ops);
602		if (kerninfo.vm_ops) {
603			vma->vm_ops = kerninfo.vm_ops;
604		} else if (io_remap_pfn_range(vma, vma->vm_start,
605				(kerninfo.aper_base + offset) >> PAGE_SHIFT,
606					    size, vma->vm_page_prot)) {
607			goto out_again;
608		}
609		mutex_unlock(&(agp_fe.agp_mutex));
610		return 0;
611	}
612
613	if (test_bit(AGP_FF_IS_CONTROLLER, &priv->access_flags)) {
614		if (size != current_size)
615			goto out_inval;
616
617		DBG("controller vm_ops=%p", kerninfo.vm_ops);
618		if (kerninfo.vm_ops) {
619			vma->vm_ops = kerninfo.vm_ops;
620		} else if (io_remap_pfn_range(vma, vma->vm_start,
621					    kerninfo.aper_base >> PAGE_SHIFT,
622					    size, vma->vm_page_prot)) {
623			goto out_again;
624		}
625		mutex_unlock(&(agp_fe.agp_mutex));
626		return 0;
627	}
628
629out_eperm:
630	mutex_unlock(&(agp_fe.agp_mutex));
631	return -EPERM;
632
633out_inval:
634	mutex_unlock(&(agp_fe.agp_mutex));
635	return -EINVAL;
636
637out_again:
638	mutex_unlock(&(agp_fe.agp_mutex));
639	return -EAGAIN;
640}
641
642static int agp_release(struct inode *inode, struct file *file)
643{
644	struct agp_file_private *priv = file->private_data;
645
646	mutex_lock(&(agp_fe.agp_mutex));
647
648	DBG("priv=%p", priv);
649
650	if (test_bit(AGP_FF_IS_CONTROLLER, &priv->access_flags)) {
651		struct agp_controller *controller;
652
653		controller = agp_find_controller_by_pid(priv->my_pid);
654
655		if (controller != NULL) {
656			if (controller == agp_fe.current_controller)
657				agp_controller_release_current(controller, priv);
658			agp_remove_controller(controller);
659			controller = NULL;
660		}
661	}
662
663	if (test_bit(AGP_FF_IS_CLIENT, &priv->access_flags))
664		agp_remove_client(priv->my_pid);
665
666	agp_remove_file_private(priv);
667	kfree(priv);
668	file->private_data = NULL;
669	mutex_unlock(&(agp_fe.agp_mutex));
670	return 0;
671}
672
673static int agp_open(struct inode *inode, struct file *file)
674{
675	int minor = iminor(inode);
676	struct agp_file_private *priv;
677	struct agp_client *client;
678
679	if (minor != AGPGART_MINOR)
680		return -ENXIO;
681
682	mutex_lock(&(agp_fe.agp_mutex));
683
684	priv = kzalloc(sizeof(struct agp_file_private), GFP_KERNEL);
685	if (priv == NULL) {
686		mutex_unlock(&(agp_fe.agp_mutex));
687		return -ENOMEM;
688	}
689
690	set_bit(AGP_FF_ALLOW_CLIENT, &priv->access_flags);
691	priv->my_pid = current->pid;
692
693	if (capable(CAP_SYS_RAWIO))
694		/* Root priv, can be controller */
695		set_bit(AGP_FF_ALLOW_CONTROLLER, &priv->access_flags);
696
697	client = agp_find_client_by_pid(current->pid);
698
699	if (client != NULL) {
700		set_bit(AGP_FF_IS_CLIENT, &priv->access_flags);
701		set_bit(AGP_FF_IS_VALID, &priv->access_flags);
702	}
703	file->private_data = (void *) priv;
704	agp_insert_file_private(priv);
705	DBG("private=%p, client=%p", priv, client);
706
707	mutex_unlock(&(agp_fe.agp_mutex));
708
709	return 0;
710}
711
712
713static ssize_t agp_read(struct file *file, char __user *buf,
714			size_t count, loff_t * ppos)
715{
716	return -EINVAL;
717}
718
719static ssize_t agp_write(struct file *file, const char __user *buf,
720			 size_t count, loff_t * ppos)
721{
722	return -EINVAL;
723}
724
725static int agpioc_info_wrap(struct agp_file_private *priv, void __user *arg)
726{
727	struct agp_info userinfo;
728	struct agp_kern_info kerninfo;
729
730	agp_copy_info(agp_bridge, &kerninfo);
731
732	userinfo.version.major = kerninfo.version.major;
733	userinfo.version.minor = kerninfo.version.minor;
734	userinfo.bridge_id = kerninfo.device->vendor |
735	    (kerninfo.device->device << 16);
736	userinfo.agp_mode = kerninfo.mode;
737	userinfo.aper_base = kerninfo.aper_base;
738	userinfo.aper_size = kerninfo.aper_size;
739	userinfo.pg_total = userinfo.pg_system = kerninfo.max_memory;
740	userinfo.pg_used = kerninfo.current_memory;
741
742	if (copy_to_user(arg, &userinfo, sizeof(struct agp_info)))
743		return -EFAULT;
744
745	return 0;
746}
747
748int agpioc_acquire_wrap(struct agp_file_private *priv)
749{
750	struct agp_controller *controller;
751
752	DBG("");
753
754	if (!(test_bit(AGP_FF_ALLOW_CONTROLLER, &priv->access_flags)))
755		return -EPERM;
756
757	if (agp_fe.current_controller != NULL)
758		return -EBUSY;
759
760	if (!agp_bridge)
761		return -ENODEV;
762
763        if (atomic_read(&agp_bridge->agp_in_use))
764                return -EBUSY;
765
766	atomic_inc(&agp_bridge->agp_in_use);
767
768	agp_fe.backend_acquired = true;
769
770	controller = agp_find_controller_by_pid(priv->my_pid);
771
772	if (controller != NULL) {
773		agp_controller_make_current(controller);
774	} else {
775		controller = agp_create_controller(priv->my_pid);
776
777		if (controller == NULL) {
778			agp_fe.backend_acquired = false;
779			agp_backend_release(agp_bridge);
780			return -ENOMEM;
781		}
782		agp_insert_controller(controller);
783		agp_controller_make_current(controller);
784	}
785
786	set_bit(AGP_FF_IS_CONTROLLER, &priv->access_flags);
787	set_bit(AGP_FF_IS_VALID, &priv->access_flags);
788	return 0;
789}
790
791int agpioc_release_wrap(struct agp_file_private *priv)
792{
793	DBG("");
794	agp_controller_release_current(agp_fe.current_controller, priv);
795	return 0;
796}
797
798int agpioc_setup_wrap(struct agp_file_private *priv, void __user *arg)
799{
800	struct agp_setup mode;
801
802	DBG("");
803	if (copy_from_user(&mode, arg, sizeof(struct agp_setup)))
804		return -EFAULT;
805
806	agp_enable(agp_bridge, mode.agp_mode);
807	return 0;
808}
809
810static int agpioc_reserve_wrap(struct agp_file_private *priv, void __user *arg)
811{
812	struct agp_region reserve;
813	struct agp_client *client;
814	struct agp_file_private *client_priv;
815
816	DBG("");
817	if (copy_from_user(&reserve, arg, sizeof(struct agp_region)))
818		return -EFAULT;
819
820	if ((unsigned) reserve.seg_count >= ~0U/sizeof(struct agp_segment))
821		return -EFAULT;
822
823	client = agp_find_client_by_pid(reserve.pid);
824
825	if (reserve.seg_count == 0) {
826		/* remove a client */
827		client_priv = agp_find_private(reserve.pid);
828
829		if (client_priv != NULL) {
830			set_bit(AGP_FF_IS_CLIENT, &client_priv->access_flags);
831			set_bit(AGP_FF_IS_VALID, &client_priv->access_flags);
832		}
833		if (client == NULL) {
834			/* client is already removed */
835			return 0;
836		}
837		return agp_remove_client(reserve.pid);
838	} else {
839		struct agp_segment *segment;
840
841		if (reserve.seg_count >= 16384)
842			return -EINVAL;
843
844		segment = kmalloc((sizeof(struct agp_segment) * reserve.seg_count),
845				  GFP_KERNEL);
846
847		if (segment == NULL)
848			return -ENOMEM;
849
850		if (copy_from_user(segment, (void __user *) reserve.seg_list,
851				   sizeof(struct agp_segment) * reserve.seg_count)) {
852			kfree(segment);
853			return -EFAULT;
854		}
855		reserve.seg_list = segment;
856
857		if (client == NULL) {
858			/* Create the client and add the segment */
859			client = agp_create_client(reserve.pid);
860
861			if (client == NULL) {
862				kfree(segment);
863				return -ENOMEM;
864			}
865			client_priv = agp_find_private(reserve.pid);
866
867			if (client_priv != NULL) {
868				set_bit(AGP_FF_IS_CLIENT, &client_priv->access_flags);
869				set_bit(AGP_FF_IS_VALID, &client_priv->access_flags);
870			}
871		}
872		return agp_create_segment(client, &reserve);
873	}
874	/* Will never really happen */
875	return -EINVAL;
876}
877
878int agpioc_protect_wrap(struct agp_file_private *priv)
879{
880	DBG("");
881	/* This function is not currently implemented */
882	return -EINVAL;
883}
884
885static int agpioc_allocate_wrap(struct agp_file_private *priv, void __user *arg)
886{
887	struct agp_memory *memory;
888	struct agp_allocate alloc;
889
890	DBG("");
891	if (copy_from_user(&alloc, arg, sizeof(struct agp_allocate)))
892		return -EFAULT;
893
894	if (alloc.type >= AGP_USER_TYPES)
895		return -EINVAL;
896
897	memory = agp_allocate_memory_wrap(alloc.pg_count, alloc.type);
898
899	if (memory == NULL)
900		return -ENOMEM;
901
902	alloc.key = memory->key;
903	alloc.physical = memory->physical;
904
905	if (copy_to_user(arg, &alloc, sizeof(struct agp_allocate))) {
906		agp_free_memory_wrap(memory);
907		return -EFAULT;
908	}
909	return 0;
910}
911
912int agpioc_deallocate_wrap(struct agp_file_private *priv, int arg)
913{
914	struct agp_memory *memory;
915
916	DBG("");
917	memory = agp_find_mem_by_key(arg);
918
919	if (memory == NULL)
920		return -EINVAL;
921
922	agp_free_memory_wrap(memory);
923	return 0;
924}
925
926static int agpioc_bind_wrap(struct agp_file_private *priv, void __user *arg)
927{
928	struct agp_bind bind_info;
929	struct agp_memory *memory;
930
931	DBG("");
932	if (copy_from_user(&bind_info, arg, sizeof(struct agp_bind)))
933		return -EFAULT;
934
935	memory = agp_find_mem_by_key(bind_info.key);
936
937	if (memory == NULL)
938		return -EINVAL;
939
940	return agp_bind_memory(memory, bind_info.pg_start);
941}
942
943static int agpioc_unbind_wrap(struct agp_file_private *priv, void __user *arg)
944{
945	struct agp_memory *memory;
946	struct agp_unbind unbind;
947
948	DBG("");
949	if (copy_from_user(&unbind, arg, sizeof(struct agp_unbind)))
950		return -EFAULT;
951
952	memory = agp_find_mem_by_key(unbind.key);
953
954	if (memory == NULL)
955		return -EINVAL;
956
957	return agp_unbind_memory(memory);
958}
959
960static long agp_ioctl(struct file *file,
961		     unsigned int cmd, unsigned long arg)
962{
963	struct agp_file_private *curr_priv = file->private_data;
964	int ret_val = -ENOTTY;
965
966	DBG("priv=%p, cmd=%x", curr_priv, cmd);
967	mutex_lock(&(agp_fe.agp_mutex));
968
969	if ((agp_fe.current_controller == NULL) &&
970	    (cmd != AGPIOC_ACQUIRE)) {
971		ret_val = -EINVAL;
972		goto ioctl_out;
973	}
974	if ((agp_fe.backend_acquired != true) &&
975	    (cmd != AGPIOC_ACQUIRE)) {
976		ret_val = -EBUSY;
977		goto ioctl_out;
978	}
979	if (cmd != AGPIOC_ACQUIRE) {
980		if (!(test_bit(AGP_FF_IS_CONTROLLER, &curr_priv->access_flags))) {
981			ret_val = -EPERM;
982			goto ioctl_out;
983		}
984		/* Use the original pid of the controller,
985		 * in case it's threaded */
986
987		if (agp_fe.current_controller->pid != curr_priv->my_pid) {
988			ret_val = -EBUSY;
989			goto ioctl_out;
990		}
991	}
992
993	switch (cmd) {
994	case AGPIOC_INFO:
995		ret_val = agpioc_info_wrap(curr_priv, (void __user *) arg);
996		break;
997
998	case AGPIOC_ACQUIRE:
999		ret_val = agpioc_acquire_wrap(curr_priv);
1000		break;
1001
1002	case AGPIOC_RELEASE:
1003		ret_val = agpioc_release_wrap(curr_priv);
1004		break;
1005
1006	case AGPIOC_SETUP:
1007		ret_val = agpioc_setup_wrap(curr_priv, (void __user *) arg);
1008		break;
1009
1010	case AGPIOC_RESERVE:
1011		ret_val = agpioc_reserve_wrap(curr_priv, (void __user *) arg);
1012		break;
1013
1014	case AGPIOC_PROTECT:
1015		ret_val = agpioc_protect_wrap(curr_priv);
1016		break;
1017
1018	case AGPIOC_ALLOCATE:
1019		ret_val = agpioc_allocate_wrap(curr_priv, (void __user *) arg);
1020		break;
1021
1022	case AGPIOC_DEALLOCATE:
1023		ret_val = agpioc_deallocate_wrap(curr_priv, (int) arg);
1024		break;
1025
1026	case AGPIOC_BIND:
1027		ret_val = agpioc_bind_wrap(curr_priv, (void __user *) arg);
1028		break;
1029
1030	case AGPIOC_UNBIND:
1031		ret_val = agpioc_unbind_wrap(curr_priv, (void __user *) arg);
1032		break;
1033
1034	case AGPIOC_CHIPSET_FLUSH:
1035		break;
1036	}
1037
1038ioctl_out:
1039	DBG("ioctl returns %d\n", ret_val);
1040	mutex_unlock(&(agp_fe.agp_mutex));
1041	return ret_val;
1042}
1043
1044static const struct file_operations agp_fops =
1045{
1046	.owner		= THIS_MODULE,
1047	.llseek		= no_llseek,
1048	.read		= agp_read,
1049	.write		= agp_write,
1050	.unlocked_ioctl	= agp_ioctl,
1051#ifdef CONFIG_COMPAT
1052	.compat_ioctl	= compat_agp_ioctl,
1053#endif
1054	.mmap		= agp_mmap,
1055	.open		= agp_open,
1056	.release	= agp_release,
1057};
1058
1059static struct miscdevice agp_miscdev =
1060{
1061	.minor	= AGPGART_MINOR,
1062	.name	= "agpgart",
1063	.fops	= &agp_fops
1064};
1065
1066int agp_frontend_initialize(void)
1067{
1068	memset(&agp_fe, 0, sizeof(struct agp_front_data));
1069	mutex_init(&(agp_fe.agp_mutex));
1070
1071	if (misc_register(&agp_miscdev)) {
1072		printk(KERN_ERR PFX "unable to get minor: %d\n", AGPGART_MINOR);
1073		return -EIO;
1074	}
1075	return 0;
1076}
1077
1078void agp_frontend_cleanup(void)
1079{
1080	misc_deregister(&agp_miscdev);
1081}
1082