/**
 * \file drm_drv.c
 * Generic driver template
 *
 * \author Rickard E. (Rik) Faith <faith@valinux.com>
 * \author Gareth Hughes <gareth@valinux.com>
 *
 * To use this template, you must at least define the following (samples
 * given for the MGA driver):
 *
 * \code
 * #define DRIVER_AUTHOR        "VA Linux Systems, Inc."
 *
 * #define DRIVER_NAME          "mga"
 * #define DRIVER_DESC          "Matrox G200/G400"
 * #define DRIVER_DATE          "20001127"
 *
 * #define drm_x                mga_##x
 * \endcode
 */

/*
 * Created: Thu Nov 23 03:10:50 2000 by gareth@valinux.com
 *
 * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
 * All Rights Reserved.
 *
 * 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 (including the next
 * paragraph) 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
 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS 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.
 */

#include <linux/debugfs.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <drm/drmP.h>
#include <drm/drm_core.h>


static int drm_version(struct drm_device *dev, void *data,
                       struct drm_file *file_priv);

#define DRM_IOCTL_DEF(ioctl, _func, _flags) \
        [DRM_IOCTL_NR(ioctl)] = {.cmd = ioctl, .func = _func, .flags = _flags, .cmd_drv = 0, .name = #ioctl}

/** Ioctl table */
static const struct drm_ioctl_desc drm_ioctls[] = {
        DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0),
        DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, 0),
        DRM_IOCTL_DEF(DRM_IOCTL_IRQ_BUSID, drm_irq_by_busid, DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_GET_MAP, drm_getmap, DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER),

        DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_setunique, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_AUTH|DRM_MASTER),

        DRM_IOCTL_DEF(DRM_IOCTL_ADD_MAP, drm_addmap_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_RM_MAP, drm_rmmap_ioctl, DRM_AUTH),

        DRM_IOCTL_DEF(DRM_IOCTL_SET_SAREA_CTX, drm_setsareactx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_GET_SAREA_CTX, drm_getsareactx, DRM_AUTH),

        DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, DRM_ROOT_ONLY),

        DRM_IOCTL_DEF(DRM_IOCTL_ADD_CTX, drm_addctx, DRM_AUTH|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_RM_CTX, drm_rmctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_MOD_CTX, drm_modctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_GET_CTX, drm_getctx, DRM_AUTH),
        DRM_IOCTL_DEF(DRM_IOCTL_SWITCH_CTX, drm_switchctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_NEW_CTX, drm_newctx, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_RES_CTX, drm_resctx, DRM_AUTH),

        DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),

        DRM_IOCTL_DEF(DRM_IOCTL_LOCK, drm_lock, DRM_AUTH),
        DRM_IOCTL_DEF(DRM_IOCTL_UNLOCK, drm_unlock, DRM_AUTH),

        DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH),

        DRM_IOCTL_DEF(DRM_IOCTL_ADD_BUFS, drm_addbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_MARK_BUFS, drm_markbufs, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_INFO_BUFS, drm_infobufs, DRM_AUTH),
        DRM_IOCTL_DEF(DRM_IOCTL_MAP_BUFS, drm_mapbufs, DRM_AUTH),
        DRM_IOCTL_DEF(DRM_IOCTL_FREE_BUFS, drm_freebufs, DRM_AUTH),
        /* The DRM_IOCTL_DMA ioctl should be defined by the driver. */
        DRM_IOCTL_DEF(DRM_IOCTL_DMA, NULL, DRM_AUTH),

        DRM_IOCTL_DEF(DRM_IOCTL_CONTROL, drm_control, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),

#if __OS_HAS_AGP
        DRM_IOCTL_DEF(DRM_IOCTL_AGP_ACQUIRE, drm_agp_acquire_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_AGP_RELEASE, drm_agp_release_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_AGP_ENABLE, drm_agp_enable_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_AGP_INFO, drm_agp_info_ioctl, DRM_AUTH),
        DRM_IOCTL_DEF(DRM_IOCTL_AGP_ALLOC, drm_agp_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_AGP_FREE, drm_agp_free_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_AGP_BIND, drm_agp_bind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_AGP_UNBIND, drm_agp_unbind_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
#endif

        DRM_IOCTL_DEF(DRM_IOCTL_SG_ALLOC, drm_sg_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF(DRM_IOCTL_SG_FREE, drm_sg_free, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),

        DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank, DRM_UNLOCKED),

        DRM_IOCTL_DEF(DRM_IOCTL_MODESET_CTL, drm_modeset_ctl, 0),

        DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),

        DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH|DRM_UNLOCKED),

        DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, DRM_CONTROL_ALLOW|DRM_UNLOCKED),

        DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_AUTH|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_AUTH|DRM_UNLOCKED),

        DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_mode_connector_property_set_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
        DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
};

#define DRM_CORE_IOCTL_COUNT    ARRAY_SIZE( drm_ioctls )

/**
 * Take down the DRM device.
 *
 * \param dev DRM device structure.
 *
 * Frees every resource in \p dev.
 *
 * \sa drm_device
 */
int drm_lastclose(struct drm_device * dev)
{
        struct drm_vma_entry *vma, *vma_temp;

        DRM_DEBUG("\n");

        if (dev->driver->lastclose)
                dev->driver->lastclose(dev);
        DRM_DEBUG("driver lastclose completed\n");

        if (dev->irq_enabled && !drm_core_check_feature(dev, DRIVER_MODESET))
                drm_irq_uninstall(dev);

        mutex_lock(&dev->struct_mutex);

        /* Clear AGP information */
        if (drm_core_has_AGP(dev) && dev->agp &&
                        !drm_core_check_feature(dev, DRIVER_MODESET)) {
                struct drm_agp_mem *entry, *tempe;

                /* Remove AGP resources, but leave dev->agp
                   intact until drv_cleanup is called. */
                list_for_each_entry_safe(entry, tempe, &dev->agp->memory, head) {
                        if (entry->bound)
                                drm_unbind_agp(entry->memory);
                        drm_free_agp(entry->memory, entry->pages);
                        kfree(entry);
                }
                INIT_LIST_HEAD(&dev->agp->memory);

                if (dev->agp->acquired)
                        drm_agp_release(dev);

                dev->agp->acquired = 0;
                dev->agp->enabled = 0;
        }
        if (drm_core_check_feature(dev, DRIVER_SG) && dev->sg &&
            !drm_core_check_feature(dev, DRIVER_MODESET)) {
                drm_sg_cleanup(dev->sg);
                dev->sg = NULL;
        }

        /* Clear vma list (only built for debugging) */
        list_for_each_entry_safe(vma, vma_temp, &dev->vmalist, head) {
                list_del(&vma->head);
                kfree(vma);
        }

        if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) &&
            !drm_core_check_feature(dev, DRIVER_MODESET))
                drm_dma_takedown(dev);

        dev->dev_mapping = NULL;
        mutex_unlock(&dev->struct_mutex);

        DRM_DEBUG("lastclose completed\n");
        return 0;
}

/** File operations structure */
static const struct file_operations drm_stub_fops = {
        .owner = THIS_MODULE,
        .open = drm_stub_open,
        .llseek = noop_llseek,
};

static int __init drm_core_init(void)
{
        int ret = -ENOMEM;

        drm_global_init();
        idr_init(&drm_minors_idr);

        if (register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops))
                goto err_p1;

        drm_class = drm_sysfs_create(THIS_MODULE, "drm");
        if (IS_ERR(drm_class)) {
                printk(KERN_ERR "DRM: Error creating drm class.\n");
                ret = PTR_ERR(drm_class);
                goto err_p2;
        }

        drm_proc_root = proc_mkdir("dri", NULL);
        if (!drm_proc_root) {
                DRM_ERROR("Cannot create /proc/dri\n");
                ret = -1;
                goto err_p3;
        }

        drm_debugfs_root = debugfs_create_dir("dri", NULL);
        if (!drm_debugfs_root) {
                DRM_ERROR("Cannot create /sys/kernel/debug/dri\n");
                ret = -1;
                goto err_p3;
        }

        DRM_INFO("Initialized %s %d.%d.%d %s\n",
                 CORE_NAME, CORE_MAJOR, CORE_MINOR, CORE_PATCHLEVEL, CORE_DATE);
        return 0;
err_p3:
        drm_sysfs_destroy();
err_p2:
        unregister_chrdev(DRM_MAJOR, "drm");

        idr_destroy(&drm_minors_idr);
err_p1:
        return ret;
}

static void __exit drm_core_exit(void)
{
        remove_proc_entry("dri", NULL);
        debugfs_remove(drm_debugfs_root);
        drm_sysfs_destroy();

        unregister_chrdev(DRM_MAJOR, "drm");

        idr_destroy(&drm_minors_idr);
}

module_init(drm_core_init);
module_exit(drm_core_exit);

/**
 * Copy and IOCTL return string to user space
 */
static int drm_copy_field(char *buf, size_t *buf_len, const char *value)
{
        int len;

        /* don't overflow userbuf */
        len = strlen(value);
        if (len > *buf_len)
                len = *buf_len;

        /* let userspace know exact length of driver value (which could be
         * larger than the userspace-supplied buffer) */
        *buf_len = strlen(value);

        /* finally, try filling in the userbuf */
        if (len && buf)
                if (copy_to_user(buf, value, len))
                        return -EFAULT;
        return 0;
}

/**
 * Get version information
 *
 * \param inode device inode.
 * \param filp file pointer.
 * \param cmd command.
 * \param arg user argument, pointing to a drm_version structure.
 * \return zero on success or negative number on failure.
 *
 * Fills in the version information in \p arg.
 */
static int drm_version(struct drm_device *dev, void *data,
                       struct drm_file *file_priv)
{
        struct drm_version *version = data;
        int err;

        version->version_major = dev->driver->major;
        version->version_minor = dev->driver->minor;
        version->version_patchlevel = dev->driver->patchlevel;
        err = drm_copy_field(version->name, &version->name_len,
                        dev->driver->name);
        if (!err)
                err = drm_copy_field(version->date, &version->date_len,
                                dev->driver->date);
        if (!err)
                err = drm_copy_field(version->desc, &version->desc_len,
                                dev->driver->desc);

        return err;
}

/**
 * Called whenever a process performs an ioctl on /dev/drm.
 *
 * \param inode device inode.
 * \param file_priv DRM file private.
 * \param cmd command.
 * \param arg user argument.
 * \return zero on success or negative number on failure.
 *
 * Looks up the ioctl function in the ::ioctls table, checking for root
 * previleges if so required, and dispatches to the respective function.
 */
long drm_ioctl(struct file *filp,
              unsigned int cmd, unsigned long arg)
{
        struct drm_file *file_priv = filp->private_data;
        struct drm_device *dev;
        const struct drm_ioctl_desc *ioctl = NULL;
        drm_ioctl_t *func;
        unsigned int nr = DRM_IOCTL_NR(cmd);
        int retcode = -EINVAL;
        char stack_kdata[128];
        char *kdata = NULL;
        unsigned int usize, asize;

        dev = file_priv->minor->dev;

        if (drm_device_is_unplugged(dev))
                return -ENODEV;

        atomic_inc(&dev->ioctl_count);
        atomic_inc(&dev->counts[_DRM_STAT_IOCTLS]);
        ++file_priv->ioctl_count;

        if ((nr >= DRM_CORE_IOCTL_COUNT) &&
            ((nr < DRM_COMMAND_BASE) || (nr >= DRM_COMMAND_END)))
                goto err_i1;
        if ((nr >= DRM_COMMAND_BASE) && (nr < DRM_COMMAND_END) &&
            (nr < DRM_COMMAND_BASE + dev->driver->num_ioctls)) {
                u32 drv_size;
                ioctl = &dev->driver->ioctls[nr - DRM_COMMAND_BASE];
                drv_size = _IOC_SIZE(ioctl->cmd_drv);
                usize = asize = _IOC_SIZE(cmd);
                if (drv_size > asize)
                        asize = drv_size;
                cmd = ioctl->cmd_drv;
        }
        else if ((nr >= DRM_COMMAND_END) || (nr < DRM_COMMAND_BASE)) {
                ioctl = &drm_ioctls[nr];
                cmd = ioctl->cmd;
                usize = asize = _IOC_SIZE(cmd);
        } else
                goto err_i1;

        DRM_DEBUG("pid=%d, dev=0x%lx, auth=%d, %s\n",
                  task_pid_nr(current),
                  (long)old_encode_dev(file_priv->minor->device),
                  file_priv->authenticated, ioctl->name);

        /* Do not trust userspace, use our own definition */
        func = ioctl->func;
        /* is there a local override? */
        if ((nr == DRM_IOCTL_NR(DRM_IOCTL_DMA)) && dev->driver->dma_ioctl)
                func = dev->driver->dma_ioctl;

        if (!func) {
                DRM_DEBUG("no function\n");
                retcode = -EINVAL;
        } else if (((ioctl->flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN)) ||
                   ((ioctl->flags & DRM_AUTH) && !file_priv->authenticated) ||
                   ((ioctl->flags & DRM_MASTER) && !file_priv->is_master) ||
                   (!(ioctl->flags & DRM_CONTROL_ALLOW) && (file_priv->minor->type == DRM_MINOR_CONTROL))) {
                retcode = -EACCES;
        } else {
                if (cmd & (IOC_IN | IOC_OUT)) {
                        if (asize <= sizeof(stack_kdata)) {
                                kdata = stack_kdata;
                        } else {
                                kdata = kmalloc(asize, GFP_KERNEL);
                                if (!kdata) {
                                        retcode = -ENOMEM;
                                        goto err_i1;
                                }
                        }
                        if (asize > usize)
                                memset(kdata + usize, 0, asize - usize);
                }

                if (cmd & IOC_IN) {
                        if (copy_from_user(kdata, (void __user *)arg,
                                           usize) != 0) {
                                retcode = -EFAULT;
                                goto err_i1;
                        }
                } else
                        memset(kdata, 0, usize);

                if (ioctl->flags & DRM_UNLOCKED)
                        retcode = func(dev, kdata, file_priv);
                else {
                        mutex_lock(&drm_global_mutex);
                        retcode = func(dev, kdata, file_priv);
                        mutex_unlock(&drm_global_mutex);
                }

                if (cmd & IOC_OUT) {
                        if (copy_to_user((void __user *)arg, kdata,
                                         usize) != 0)
                                retcode = -EFAULT;
                }
        }

      err_i1:
        if (!ioctl)
                DRM_DEBUG("invalid iotcl: pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n",
                          task_pid_nr(current),
                          (long)old_encode_dev(file_priv->minor->device),
                          file_priv->authenticated, cmd, nr);

        if (kdata != stack_kdata)
                kfree(kdata);
        atomic_dec(&dev->ioctl_count);
        if (retcode)
                DRM_DEBUG("ret = %d\n", retcode);
        return retcode;
}

EXPORT_SYMBOL(drm_ioctl);

struct drm_local_map *drm_getsarea(struct drm_device *dev)
{
        struct drm_map_list *entry;

        list_for_each_entry(entry, &dev->maplist, head) {
                if (entry->map && entry->map->type == _DRM_SHM &&
                    (entry->map->flags & _DRM_CONTAINS_LOCK)) {
                        return entry->map;
                }
        }
        return NULL;
}
EXPORT_SYMBOL(drm_getsarea);