patch-2.2.18 linux/drivers/char/agp/agpgart_fe.c

• Lines: 1099
• Date: Tue Sep 26 17:00:25 2000
• Orig file: v2.2.17/drivers/char/agp/agpgart_fe.c
• Orig date: Thu Jan 1 01:00:00 1970

diff -u --new-file --recursive --exclude-from /usr/src/exclude v2.2.17/drivers/char/agp/agpgart_fe.c linux/drivers/char/agp/agpgart_fe.c
@@ -0,0 +1,1098 @@
+/*
+ * AGPGART module frontend version 0.99
+ * Copyright (C) 1999 Jeff Hartmann
+ * Copyright (C) 1999 Precision Insight, Inc.
+ * Copyright (C) 1999 Xi Graphics, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * JEFF HARTMANN, OR ANY OTHER CONTRIBUTORS BE LIABLE FOR ANY CLAIM, 
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR 
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE 
+ * OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ */
+
+#define __NO_VERSION__
+#include <linux/version.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/malloc.h>
+#include <linux/vmalloc.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+#include <linux/pagemap.h>
+#include <linux/miscdevice.h>
+#include <linux/agp_backend.h>
+#include "agpgart.h"
+#include <asm/system.h>
+#include <asm/uaccess.h>
+#include <asm/io.h>
+#include <asm/page.h>
+#include <asm/mman.h>
+
+#include "agp.h"
+
+static struct agp_front_data agp_fe;
+
+static agp_memory *agp_find_mem_by_key(int key)
+{
+	agp_memory *curr;
+
+	if (agp_fe.current_controller == NULL) {
+		return NULL;
+	}
+	curr = agp_fe.current_controller->pool;
+
+	while (curr != NULL) {
+		if (curr->key == key) {
+			return curr;
+		}
+		curr = curr->next;
+	}
+
+	return NULL;
+}
+
+static void agp_remove_from_pool(agp_memory * temp)
+{
+	agp_memory *prev;
+	agp_memory *next;
+
+	/* Check to see if this is even in the memory pool */
+
+	if (agp_find_mem_by_key(temp->key) != NULL) {
+		next = temp->next;
+		prev = temp->prev;
+
+		if (prev != NULL) {
+			prev->next = next;
+			if (next != NULL) {
+				next->prev = prev;
+			}
+		} else {
+			/* This is the first item on the list */
+			if (next != NULL) {
+				next->prev = NULL;
+			}
+			agp_fe.current_controller->pool = next;
+		}
+	}
+}
+
+/*
+ * Routines for managing each client's segment list -
+ * These routines handle adding and removing segments
+ * to each auth'ed client.
+ */
+
+static agp_segment_priv *agp_find_seg_in_client(const agp_client * client,
+						unsigned long offset,
+					    int size, pgprot_t page_prot)
+{
+	agp_segment_priv *seg;
+	int num_segments, pg_start, pg_count, i;
+
+	pg_start = offset / 4096;
+	pg_count = size / 4096;
+	seg = *(client->segments);
+	num_segments = client->num_segments;
+
+	for (i = 0; i < client->num_segments; i++) {
+		if ((seg[i].pg_start == pg_start) &&
+		    (seg[i].pg_count == pg_count) &&
+		    (pgprot_val(seg[i].prot) == pgprot_val(page_prot))) {
+			return seg + i;
+		}
+	}
+
+	return NULL;
+}
+
+static void agp_remove_seg_from_client(agp_client * client)
+{
+	if (client->segments != NULL) {
+		if (*(client->segments) != NULL) {
+			kfree(*(client->segments));
+		}
+		kfree(client->segments);
+	}
+}
+
+static void agp_add_seg_to_client(agp_client * client,
+			       agp_segment_priv ** seg, int num_segments)
+{
+	agp_segment_priv **prev_seg;
+
+	prev_seg = client->segments;
+
+	if (prev_seg != NULL) {
+		agp_remove_seg_from_client(client);
+	}
+	client->num_segments = num_segments;
+	client->segments = seg;
+}
+
+/* Originally taken from linux/mm/mmap.c from the array
+ * protection_map.
+ * The original really should be exported to modules, or 
+ * some routine which does the conversion for you 
+ */
+
+static const pgprot_t my_protect_map[16] =
+{
+	__P000, __P001, __P010, __P011, __P100, __P101, __P110, __P111,
+	__S000, __S001, __S010, __S011, __S100, __S101, __S110, __S111
+};
+
+static pgprot_t agp_convert_mmap_flags(int prot)
+{
+#define _trans(x,bit1,bit2) \
+((bit1==bit2)?(x&bit1):(x&bit1)?bit2:0)
+
+	unsigned long prot_bits;
+	pgprot_t temp;
+
+	prot_bits = _trans(prot, PROT_READ, VM_READ) |
+	    _trans(prot, PROT_WRITE, VM_WRITE) |
+	    _trans(prot, PROT_EXEC, VM_EXEC);
+
+	prot_bits |= VM_SHARED;
+
+	temp = my_protect_map[prot_bits & 0x0000000f];
+
+	return temp;
+}
+
+static int agp_create_segment(agp_client * client, agp_region * region)
+{
+	agp_segment_priv **ret_seg;
+	agp_segment_priv *seg;
+	agp_segment *user_seg;
+	int i;
+
+	seg = kmalloc((sizeof(agp_segment_priv) * region->seg_count),
+		      GFP_KERNEL);
+	if (seg == NULL) {
+		kfree(region->seg_list);
+		return -ENOMEM;
+	}
+	memset(seg, 0, (sizeof(agp_segment_priv) * region->seg_count));
+	user_seg = region->seg_list;
+
+	for (i = 0; i < region->seg_count; i++) {
+		seg[i].pg_start = user_seg[i].pg_start;
+		seg[i].pg_count = user_seg[i].pg_count;
+		seg[i].prot = agp_convert_mmap_flags(user_seg[i].prot);
+	}
+	ret_seg = kmalloc(sizeof(void *), GFP_KERNEL);
+	if (ret_seg == NULL) {
+		kfree(region->seg_list);
+		kfree(seg);
+		return -ENOMEM;
+	}
+	*ret_seg = seg;
+	kfree(region->seg_list);
+	agp_add_seg_to_client(client, ret_seg, region->seg_count);
+	return 0;
+}
+
+/* End - Routines for managing each client's segment list */
+
+/* This function must only be called when current_controller != NULL */
+static void agp_insert_into_pool(agp_memory * temp)
+{
+	agp_memory *prev;
+
+	prev = agp_fe.current_controller->pool;
+
+	if (prev != NULL) {
+		prev->prev = temp;
+		temp->next = prev;
+	}
+	agp_fe.current_controller->pool = temp;
+}
+
+
+/* File private list routines */
+
+agp_file_private *agp_find_private(pid_t pid)
+{
+	agp_file_private *curr;
+
+	curr = agp_fe.file_priv_list;
+
+	while (curr != NULL) {
+		if (curr->my_pid == pid) {
+			return curr;
+		}
+		curr = curr->next;
+	}
+
+	return NULL;
+}
+
+void agp_insert_file_private(agp_file_private * priv)
+{
+	agp_file_private *prev;
+
+	prev = agp_fe.file_priv_list;
+
+	if (prev != NULL) {
+		prev->prev = priv;
+	}
+	priv->next = prev;
+	agp_fe.file_priv_list = priv;
+}
+
+void agp_remove_file_private(agp_file_private * priv)
+{
+	agp_file_private *next;
+	agp_file_private *prev;
+
+	next = priv->next;
+	prev = priv->prev;
+
+	if (prev != NULL) {
+		prev->next = next;
+
+		if (next != NULL) {
+			next->prev = prev;
+		}
+	} else {
+		if (next != NULL) {
+			next->prev = NULL;
+		}
+		agp_fe.file_priv_list = next;
+	}
+}
+
+/* End - File flag list routines */
+
+/* 
+ * Wrappers for agp_free_memory & agp_allocate_memory 
+ * These make sure that internal lists are kept updated.
+ */
+static void agp_free_memory_wrap(agp_memory * memory)
+{
+	agp_remove_from_pool(memory);
+	agp_free_memory(memory);
+}
+
+static agp_memory *agp_allocate_memory_wrap(size_t pg_count, u32 type)
+{
+	agp_memory *memory;
+
+	memory = agp_allocate_memory(pg_count, type);
+   	printk(KERN_DEBUG "memory : %p\n", memory);
+	if (memory == NULL) {
+		return NULL;
+	}
+	agp_insert_into_pool(memory);
+	return memory;
+}
+
+/* Routines for managing the list of controllers -
+ * These routines manage the current controller, and the list of
+ * controllers
+ */
+
+static agp_controller *agp_find_controller_by_pid(pid_t id)
+{
+	agp_controller *controller;
+
+	controller = agp_fe.controllers;
+
+	while (controller != NULL) {
+		if (controller->pid == id) {
+			return controller;
+		}
+		controller = controller->next;
+	}
+
+	return NULL;
+}
+
+static agp_controller *agp_create_controller(pid_t id)
+{
+	agp_controller *controller;
+
+	controller = kmalloc(sizeof(agp_controller), GFP_KERNEL);
+
+	if (controller == NULL) {
+		return NULL;
+	}
+	memset(controller, 0, sizeof(agp_controller));
+	controller->pid = id;
+
+	return controller;
+}
+
+static int agp_insert_controller(agp_controller * controller)
+{
+	agp_controller *prev_controller;
+
+	prev_controller = agp_fe.controllers;
+	controller->next = prev_controller;
+
+	if (prev_controller != NULL) {
+		prev_controller->prev = controller;
+	}
+	agp_fe.controllers = controller;
+
+	return 0;
+}
+
+static void agp_remove_all_clients(agp_controller * controller)
+{
+	agp_client *client;
+	agp_client *temp;
+
+	client = controller->clients;
+
+	while (client) {
+		agp_file_private *priv;
+
+		temp = client;
+		agp_remove_seg_from_client(temp);
+		priv = agp_find_private(temp->pid);
+
+		if (priv != NULL) {
+			clear_bit(AGP_FF_IS_VALID, &priv->access_flags);
+			clear_bit(AGP_FF_IS_CLIENT, &priv->access_flags);
+		}
+		client = client->next;
+		kfree(temp);
+	}
+}
+
+static void agp_remove_all_memory(agp_controller * controller)
+{
+	agp_memory *memory;
+	agp_memory *temp;
+
+	memory = controller->pool;
+
+	while (memory) {
+		temp = memory;
+		memory = memory->next;
+		agp_free_memory_wrap(temp);
+	}
+}
+
+static int agp_remove_controller(agp_controller * controller)
+{
+	agp_controller *prev_controller;
+	agp_controller *next_controller;
+
+	prev_controller = controller->prev;
+	next_controller = controller->next;
+
+	if (prev_controller != NULL) {
+		prev_controller->next = next_controller;
+		if (next_controller != NULL) {
+			next_controller->prev = prev_controller;
+		}
+	} else {
+		if (next_controller != NULL) {
+			next_controller->prev = NULL;
+		}
+		agp_fe.controllers = next_controller;
+	}
+
+	agp_remove_all_memory(controller);
+	agp_remove_all_clients(controller);
+
+	if (agp_fe.current_controller == controller) {
+		agp_fe.current_controller = NULL;
+		agp_fe.backend_acquired = FALSE;
+		agp_backend_release();
+	}
+	kfree(controller);
+	return 0;
+}
+
+static void agp_controller_make_current(agp_controller * controller)
+{
+	agp_client *clients;
+
+	clients = controller->clients;
+
+	while (clients != NULL) {
+		agp_file_private *priv;
+
+		priv = agp_find_private(clients->pid);
+
+		if (priv != NULL) {
+			set_bit(AGP_FF_IS_VALID, &priv->access_flags);
+			set_bit(AGP_FF_IS_CLIENT, &priv->access_flags);
+		}
+		clients = clients->next;
+	}
+
+	agp_fe.current_controller = controller;
+}
+
+static void agp_controller_release_current(agp_controller * controller,
+				      agp_file_private * controller_priv)
+{
+	agp_client *clients;
+
+	clear_bit(AGP_FF_IS_VALID, &controller_priv->access_flags);
+	clients = controller->clients;
+
+	while (clients != NULL) {
+		agp_file_private *priv;
+
+		priv = agp_find_private(clients->pid);
+
+		if (priv != NULL) {
+			clear_bit(AGP_FF_IS_VALID, &priv->access_flags);
+		}
+		clients = clients->next;
+	}
+
+	agp_fe.current_controller = NULL;
+	agp_fe.used_by_controller = FALSE;
+	agp_backend_release();
+}
+
+/* 
+ * Routines for managing client lists -
+ * These routines are for managing the list of auth'ed clients.
+ */
+
+static agp_client *agp_find_client_in_controller(agp_controller * controller,
+						 pid_t id)
+{
+	agp_client *client;
+
+	if (controller == NULL) {
+		return NULL;
+	}
+	client = controller->clients;
+
+	while (client != NULL) {
+		if (client->pid == id) {
+			return client;
+		}
+		client = client->next;
+	}
+
+	return NULL;
+}
+
+static agp_controller *agp_find_controller_for_client(pid_t id)
+{
+	agp_controller *controller;
+
+	controller = agp_fe.controllers;
+
+	while (controller != NULL) {
+		if ((agp_find_client_in_controller(controller, id)) != NULL) {
+			return controller;
+		}
+		controller = controller->next;
+	}
+
+	return NULL;
+}
+
+static agp_client *agp_find_client_by_pid(pid_t id)
+{
+	agp_client *temp;
+
+	if (agp_fe.current_controller == NULL) {
+		return NULL;
+	}
+	temp = agp_find_client_in_controller(agp_fe.current_controller, id);
+	return temp;
+}
+
+static void agp_insert_client(agp_client * client)
+{
+	agp_client *prev_client;
+
+	prev_client = agp_fe.current_controller->clients;
+	client->next = prev_client;
+
+	if (prev_client != NULL) {
+		prev_client->prev = client;
+	}
+	agp_fe.current_controller->clients = client;
+	agp_fe.current_controller->num_clients++;
+}
+
+static agp_client *agp_create_client(pid_t id)
+{
+	agp_client *new_client;
+
+	new_client = kmalloc(sizeof(agp_client), GFP_KERNEL);
+
+	if (new_client == NULL) {
+		return NULL;
+	}
+	memset(new_client, 0, sizeof(agp_client));
+	new_client->pid = id;
+	agp_insert_client(new_client);
+	return new_client;
+}
+
+static int agp_remove_client(pid_t id)
+{
+	agp_client *client;
+	agp_client *prev_client;
+	agp_client *next_client;
+	agp_controller *controller;
+
+	controller = agp_find_controller_for_client(id);
+
+	if (controller == NULL) {
+		return -EINVAL;
+	}
+	client = agp_find_client_in_controller(controller, id);
+
+	if (client == NULL) {
+		return -EINVAL;
+	}
+	prev_client = client->prev;
+	next_client = client->next;
+
+	if (prev_client != NULL) {
+		prev_client->next = next_client;
+		if (next_client != NULL) {
+			next_client->prev = prev_client;
+		}
+	} else {
+		if (next_client != NULL) {
+			next_client->prev = NULL;
+		}
+		controller->clients = next_client;
+	}
+
+	controller->num_clients--;
+	agp_remove_seg_from_client(client);
+	kfree(client);
+	return 0;
+}
+
+/* End - Routines for managing client lists */
+
+/* File Operations */
+
+static int agp_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	int size;
+	int current_size;
+	unsigned long offset;
+	agp_client *client;
+	agp_file_private *priv = (agp_file_private *) file->private_data;
+	agp_kern_info kerninfo;
+
+	AGP_LOCK();
+
+	if (agp_fe.backend_acquired != TRUE) {
+		AGP_UNLOCK();
+		return -EPERM;
+	}
+	if (!(test_bit(AGP_FF_IS_VALID, &priv->access_flags))) {
+		AGP_UNLOCK();
+		return -EPERM;
+	}
+	agp_copy_info(&kerninfo);
+	size = vma->vm_end - vma->vm_start;
+	current_size = kerninfo.aper_size;
+	current_size = current_size * 0x100000;
+	offset = vma->vm_offset;
+
+	if (test_bit(AGP_FF_IS_CLIENT, &priv->access_flags)) {
+		if ((size + offset) > current_size) {
+			AGP_UNLOCK();
+			return -EINVAL;
+		}
+		client = agp_find_client_by_pid(current->pid);
+
+		if (client == NULL) {
+			AGP_UNLOCK();
+			return -EPERM;
+		}
+		if (!agp_find_seg_in_client(client, offset,
+					    size, vma->vm_page_prot)) {
+			AGP_UNLOCK();
+			return -EINVAL;
+		}
+		if (remap_page_range(vma->vm_start,
+				     (kerninfo.aper_base + offset),
+				     size, vma->vm_page_prot)) {
+			AGP_UNLOCK();
+			return -EAGAIN;
+		}
+		AGP_UNLOCK();
+		return 0;
+	}
+	if (test_bit(AGP_FF_IS_CONTROLLER, &priv->access_flags)) {
+		if (size != current_size) {
+			AGP_UNLOCK();
+			return -EINVAL;
+		}
+		if (remap_page_range(vma->vm_start, kerninfo.aper_base,
+				     size, vma->vm_page_prot)) {
+			AGP_UNLOCK();
+			return -EAGAIN;
+		}
+		AGP_UNLOCK();
+		return 0;
+	}
+	AGP_UNLOCK();
+	return -EPERM;
+}
+
+static int agp_release(struct inode *inode, struct file *file)
+{
+	agp_file_private *priv = (agp_file_private *) file->private_data;
+
+	AGP_LOCK();
+
+	if (test_bit(AGP_FF_IS_CONTROLLER, &priv->access_flags)) {
+		agp_controller *controller;
+
+		controller = agp_find_controller_by_pid(priv->my_pid);
+
+		if (controller != NULL) {
+			if (controller == agp_fe.current_controller) {
+				agp_controller_release_current(controller,
+							       priv);
+			}
+			agp_remove_controller(controller);
+		}
+	}
+	if (test_bit(AGP_FF_IS_CLIENT, &priv->access_flags)) {
+		agp_remove_client(priv->my_pid);
+	}
+	agp_remove_file_private(priv);
+	kfree(priv);
+	MOD_DEC_USE_COUNT;
+	AGP_UNLOCK();
+	return 0;
+}
+
+static int agp_open(struct inode *inode, struct file *file)
+{
+	int minor = MINOR(inode->i_rdev);
+	agp_file_private *priv;
+	agp_client *client;
+	int rc = -ENXIO;
+
+	AGP_LOCK();
+	MOD_INC_USE_COUNT;
+
+	if (minor != AGPGART_MINOR)
+		goto err_out;
+
+	priv = kmalloc(sizeof(agp_file_private), GFP_KERNEL);
+	if (priv == NULL)
+		goto err_out_nomem;
+
+	memset(priv, 0, sizeof(agp_file_private));
+	set_bit(AGP_FF_ALLOW_CLIENT, &priv->access_flags);
+	priv->my_pid = current->pid;
+
+	if ((current->uid == 0) || (current->suid == 0)) {
+		/* Root priv, can be controller */
+		set_bit(AGP_FF_ALLOW_CONTROLLER, &priv->access_flags);
+	}
+	client = agp_find_client_by_pid(current->pid);
+
+	if (client != NULL) {
+		set_bit(AGP_FF_IS_CLIENT, &priv->access_flags);
+		set_bit(AGP_FF_IS_VALID, &priv->access_flags);
+	}
+	file->private_data = (void *) priv;
+	agp_insert_file_private(priv);
+	AGP_UNLOCK();
+	return 0;
+
+err_out_nomem:
+	rc = -ENOMEM;
+err_out:
+	MOD_DEC_USE_COUNT;
+	AGP_UNLOCK();
+	return rc;
+}
+
+
+static long long agp_lseek(struct file *file, long long offset, int origin)
+{
+	return -ESPIPE;
+}
+
+static ssize_t agp_read(struct file *file, char *buf,
+			size_t count, loff_t * ppos)
+{
+	return -EINVAL;
+}
+
+static ssize_t agp_write(struct file *file, const char *buf,
+			 size_t count, loff_t * ppos)
+{
+	return -EINVAL;
+}
+
+static int agpioc_info_wrap(agp_file_private * priv, unsigned long arg)
+{
+	agp_info userinfo;
+	agp_kern_info kerninfo;
+
+	agp_copy_info(&kerninfo);
+
+	userinfo.version.major = kerninfo.version.major;
+	userinfo.version.minor = kerninfo.version.minor;
+	userinfo.bridge_id = kerninfo.device->vendor |
+	    (kerninfo.device->device << 16);
+	userinfo.agp_mode = kerninfo.mode;
+	userinfo.aper_base = kerninfo.aper_base;
+	userinfo.aper_size = kerninfo.aper_size;
+	userinfo.pg_total = userinfo.pg_system = kerninfo.max_memory;
+	userinfo.pg_used = kerninfo.current_memory;
+
+	if (copy_to_user((void *) arg, &userinfo, sizeof(agp_info))) {
+		return -EFAULT;
+	}
+	return 0;
+}
+
+static int agpioc_acquire_wrap(agp_file_private * priv, unsigned long arg)
+{
+	agp_controller *controller;
+	if (!(test_bit(AGP_FF_ALLOW_CONTROLLER, &priv->access_flags))) {
+		return -EPERM;
+	}
+	if (agp_fe.current_controller != NULL) {
+		return -EBUSY;
+	}
+	if ((agp_backend_acquire()) == 0) {
+		agp_fe.backend_acquired = TRUE;
+	} else {
+		return -EBUSY;
+	}
+
+	controller = agp_find_controller_by_pid(priv->my_pid);
+
+	if (controller != NULL) {
+		agp_controller_make_current(controller);
+	} else {
+		controller = agp_create_controller(priv->my_pid);
+
+		if (controller == NULL) {
+			agp_fe.backend_acquired = FALSE;
+			agp_backend_release();
+			return -ENOMEM;
+		}
+		agp_insert_controller(controller);
+		agp_controller_make_current(controller);
+	}
+
+	set_bit(AGP_FF_IS_CONTROLLER, &priv->access_flags);
+	set_bit(AGP_FF_IS_VALID, &priv->access_flags);
+	return 0;
+}
+
+static int agpioc_release_wrap(agp_file_private * priv, unsigned long arg)
+{
+	agp_controller_release_current(agp_fe.current_controller, priv);
+	return 0;
+}
+
+static int agpioc_setup_wrap(agp_file_private * priv, unsigned long arg)
+{
+	agp_setup mode;
+
+	if (copy_from_user(&mode, (void *) arg, sizeof(agp_setup))) {
+		return -EFAULT;
+	}
+	agp_enable(mode.agp_mode);
+	return 0;
+}
+
+static int agpioc_reserve_wrap(agp_file_private * priv, unsigned long arg)
+{
+	agp_region reserve;
+	agp_client *client;
+	agp_file_private *client_priv;
+
+
+	if (copy_from_user(&reserve, (void *) arg, sizeof(agp_region))) {
+		return -EFAULT;
+	}
+	client = agp_find_client_by_pid(reserve.pid);
+
+	if (reserve.seg_count == 0) {
+		/* remove a client */
+		client_priv = agp_find_private(reserve.pid);
+
+		if (client_priv != NULL) {
+			set_bit(AGP_FF_IS_CLIENT,
+				&client_priv->access_flags);
+			set_bit(AGP_FF_IS_VALID,
+				&client_priv->access_flags);
+		}
+		if (client == NULL) {
+			/* client is already removed */
+			return 0;
+		}
+		return agp_remove_client(reserve.pid);
+	} else {
+		agp_segment *segment;
+
+		segment = kmalloc((sizeof(agp_segment) * reserve.seg_count),
+				  GFP_KERNEL);
+
+		if (segment == NULL) {
+			return -ENOMEM;
+		}
+		if (copy_from_user(segment, (void *) reserve.seg_list,
+				   GFP_KERNEL)) {
+			kfree(segment);
+			return -EFAULT;
+		}
+		reserve.seg_list = segment;
+
+		if (client == NULL) {
+			/* Create the client and add the segment */
+			client = agp_create_client(reserve.pid);
+
+			if (client == NULL) {
+				kfree(segment);
+				return -ENOMEM;
+			}
+			client_priv = agp_find_private(reserve.pid);
+
+			if (client_priv != NULL) {
+				set_bit(AGP_FF_IS_CLIENT,
+					&client_priv->access_flags);
+				set_bit(AGP_FF_IS_VALID,
+					&client_priv->access_flags);
+			}
+			return agp_create_segment(client, &reserve);
+		} else {
+			return agp_create_segment(client, &reserve);
+		}
+	}
+	/* Will never really happen */
+	return -EINVAL;
+}
+
+static int agpioc_protect_wrap(agp_file_private * priv, unsigned long arg)
+{
+	/* This function is not currently implemented */
+	return -EINVAL;
+}
+
+static int agpioc_allocate_wrap(agp_file_private * priv, unsigned long arg)
+{
+	agp_memory *memory;
+	agp_allocate alloc;
+
+	if (copy_from_user(&alloc, (void *) arg, sizeof(agp_allocate))) {
+		return -EFAULT;
+	}
+	memory = agp_allocate_memory_wrap(alloc.pg_count, alloc.type);
+
+	if (memory == NULL) {
+		return -ENOMEM;
+	}
+	alloc.key = memory->key;
+	alloc.physical = memory->physical;
+
+	if (copy_to_user((void *) arg, &alloc, sizeof(agp_allocate))) {
+		agp_free_memory_wrap(memory);
+		return -EFAULT;
+	}
+	return 0;
+}
+
+static int agpioc_deallocate_wrap(agp_file_private * priv, unsigned long arg)
+{
+	agp_memory *memory;
+
+	memory = agp_find_mem_by_key((int) arg);
+
+	if (memory == NULL) {
+		return -EINVAL;
+	}
+	agp_free_memory_wrap(memory);
+	return 0;
+}
+
+static int agpioc_bind_wrap(agp_file_private * priv, unsigned long arg)
+{
+	agp_bind bind_info;
+	agp_memory *memory;
+
+	if (copy_from_user(&bind_info, (void *) arg, sizeof(agp_bind))) {
+		return -EFAULT;
+	}
+	memory = agp_find_mem_by_key(bind_info.key);
+
+	if (memory == NULL) {
+		return -EINVAL;
+	}
+	return agp_bind_memory(memory, bind_info.pg_start);
+}
+
+static int agpioc_unbind_wrap(agp_file_private * priv, unsigned long arg)
+{
+	agp_memory *memory;
+	agp_unbind unbind;
+
+	if (copy_from_user(&unbind, (void *) arg, sizeof(agp_unbind))) {
+		return -EFAULT;
+	}
+	memory = agp_find_mem_by_key(unbind.key);
+
+	if (memory == NULL) {
+		return -EINVAL;
+	}
+	return agp_unbind_memory(memory);
+}
+
+static int agp_ioctl(struct inode *inode, struct file *file,
+		     unsigned int cmd, unsigned long arg)
+{
+	agp_file_private *curr_priv = (agp_file_private *) file->private_data;
+	int ret_val = -ENOTTY;
+
+	AGP_LOCK();
+
+	if ((agp_fe.current_controller == NULL) &&
+	    (cmd != AGPIOC_ACQUIRE)) {
+		ret_val = -EINVAL;
+	   	goto ioctl_out;
+	}
+	if ((agp_fe.backend_acquired != TRUE) &&
+	    (cmd != AGPIOC_ACQUIRE)) {
+		ret_val = -EBUSY;
+	   	goto ioctl_out;
+	}
+	if (cmd != AGPIOC_ACQUIRE) {
+		if (!(test_bit(AGP_FF_IS_CONTROLLER,
+			       &curr_priv->access_flags))) {
+			ret_val = -EPERM;
+		   	goto ioctl_out;
+		}
+		/* Use the original pid of the controller,
+		 * in case it's threaded */
+
+		if (agp_fe.current_controller->pid != curr_priv->my_pid) {
+			ret_val = -EBUSY;
+		   	goto ioctl_out;
+		}
+	}
+	switch (cmd) {
+	case AGPIOC_INFO:
+		{
+			ret_val = agpioc_info_wrap(curr_priv, arg);
+		   	goto ioctl_out;
+		}
+	case AGPIOC_ACQUIRE:
+		{
+			ret_val = agpioc_acquire_wrap(curr_priv, arg);
+		   	goto ioctl_out;
+		}
+	case AGPIOC_RELEASE:
+		{
+			ret_val = agpioc_release_wrap(curr_priv, arg);
+		   	goto ioctl_out;
+		}
+	case AGPIOC_SETUP:
+		{
+			ret_val = agpioc_setup_wrap(curr_priv, arg);
+		   	goto ioctl_out;
+		}
+	case AGPIOC_RESERVE:
+		{
+			ret_val = agpioc_reserve_wrap(curr_priv, arg);
+		   	goto ioctl_out;
+		}
+	case AGPIOC_PROTECT:
+		{
+			ret_val = agpioc_protect_wrap(curr_priv, arg);
+		   	goto ioctl_out;
+		}
+	case AGPIOC_ALLOCATE:
+		{
+			ret_val = agpioc_allocate_wrap(curr_priv, arg);
+		   	goto ioctl_out;
+		}
+	case AGPIOC_DEALLOCATE:
+		{
+			ret_val = agpioc_deallocate_wrap(curr_priv, arg);
+		   	goto ioctl_out;
+		}
+	case AGPIOC_BIND:
+		{
+			ret_val = agpioc_bind_wrap(curr_priv, arg);
+		   	goto ioctl_out;
+		}
+	case AGPIOC_UNBIND:
+		{
+			ret_val = agpioc_unbind_wrap(curr_priv, arg);
+		   	goto ioctl_out;
+		}
+	}
+   
+ioctl_out:
+	AGP_UNLOCK();
+	return ret_val;
+}
+
+static struct file_operations agp_fops =
+{
+	llseek:		agp_lseek,
+	read:		agp_read,
+	write:		agp_write,
+	ioctl:		agp_ioctl,
+	mmap:		agp_mmap,
+	open:		agp_open,
+	release:	agp_release,
+};
+
+static struct miscdevice agp_miscdev =
+{
+	AGPGART_MINOR,
+	AGPGART_MODULE_NAME,
+	&agp_fops
+};
+
+int __init agp_frontend_initialize(void)
+{
+	memset(&agp_fe, 0, sizeof(struct agp_front_data));
+	AGP_LOCK_INIT();
+
+	if (misc_register(&agp_miscdev)) {
+		printk(KERN_ERR PFX "unable to get minor: %d\n", AGPGART_MINOR);
+		return -EIO;
+	}
+	return 0;
+}
+
+void agp_frontend_cleanup(void)
+{
+	misc_deregister(&agp_miscdev);
+}