/*
 * 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/slab.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 <linux/agpgart.h>
#include <linux/smp_lock.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;

        lock_kernel();
        AGP_LOCK();

        if (agp_fe.backend_acquired != TRUE) {
                AGP_UNLOCK();
                unlock_kernel();
                return -EPERM;
        }
        if (!(test_bit(AGP_FF_IS_VALID, &priv->access_flags))) {
                AGP_UNLOCK();
                unlock_kernel();
                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_pgoff << PAGE_SHIFT;

        if (test_bit(AGP_FF_IS_CLIENT, &priv->access_flags)) {
                if ((size + offset) > current_size) {
                        AGP_UNLOCK();
                        unlock_kernel();
                        return -EINVAL;
                }
                client = agp_find_client_by_pid(current->pid);

                if (client == NULL) {
                        AGP_UNLOCK();
                        unlock_kernel();
                        return -EPERM;
                }
                if (!agp_find_seg_in_client(client, offset,
                                            size, vma->vm_page_prot)) {
                        AGP_UNLOCK();
                        unlock_kernel();
                        return -EINVAL;
                }
                if (remap_page_range(vma->vm_start,
                                     (kerninfo.aper_base + offset),
                                     size, vma->vm_page_prot)) {
                        AGP_UNLOCK();
                        unlock_kernel();
                        return -EAGAIN;
                }
                AGP_UNLOCK();
                unlock_kernel();
                return 0;
        }
        if (test_bit(AGP_FF_IS_CONTROLLER, &priv->access_flags)) {
                if (size != current_size) {
                        AGP_UNLOCK();
                        unlock_kernel();
                        return -EINVAL;
                }
                if (remap_page_range(vma->vm_start, kerninfo.aper_base,
                                     size, vma->vm_page_prot)) {
                        AGP_UNLOCK();
                        unlock_kernel();
                        return -EAGAIN;
                }
                AGP_UNLOCK();
                unlock_kernel();
                return 0;
        }
        AGP_UNLOCK();
        unlock_kernel();
        return -EPERM;
}

static int agp_release(struct inode *inode, struct file *file)
{
        agp_file_private *priv = (agp_file_private *) file->private_data;

        lock_kernel();
        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);
        AGP_UNLOCK();
        unlock_kernel();
        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();

        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:
        AGP_UNLOCK();
        return rc;
}


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;
        }
        if ((unsigned) reserve.seg_count >= ~0U/sizeof(agp_segment))
                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;

                if (reserve.seg_count >= 16384)
                        return -EINVAL;
                        
                segment = kmalloc((sizeof(agp_segment) * reserve.seg_count),
                                  GFP_KERNEL);

                if (segment == NULL) {
                        return -ENOMEM;
                }
                if (copy_from_user(segment, (void *) reserve.seg_list,
                                   sizeof(agp_segment) * reserve.seg_count)) {
                        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 =
{
        owner:          THIS_MODULE,
        llseek:         no_llseek,
        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 __exit agp_frontend_cleanup(void)
{
        misc_deregister(&agp_miscdev);
}