/*
 * \file drm_ioc32.c
 *
 * 32-bit ioctl compatibility routines for the DRM.
 *
 * \author Paul Mackerras <paulus@samba.org>
 *
 * Copyright (C) Paul Mackerras 2005.
 * 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
 * THE AUTHOR 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/compat.h>
#include <linux/ratelimit.h>
#include <linux/export.h>

#include <drm/drm_agpsupport.h>
#include <drm/drm_file.h>
#include <drm/drm_print.h>

#include "drm_crtc_internal.h"
#include "drm_internal.h"
#include "drm_legacy.h"

#define DRM_IOCTL_VERSION32             DRM_IOWR(0x00, drm_version32_t)
#define DRM_IOCTL_GET_UNIQUE32          DRM_IOWR(0x01, drm_unique32_t)
#define DRM_IOCTL_GET_MAP32             DRM_IOWR(0x04, drm_map32_t)
#define DRM_IOCTL_GET_CLIENT32          DRM_IOWR(0x05, drm_client32_t)
#define DRM_IOCTL_GET_STATS32           DRM_IOR( 0x06, drm_stats32_t)

#define DRM_IOCTL_SET_UNIQUE32          DRM_IOW( 0x10, drm_unique32_t)
#define DRM_IOCTL_ADD_MAP32             DRM_IOWR(0x15, drm_map32_t)
#define DRM_IOCTL_ADD_BUFS32            DRM_IOWR(0x16, drm_buf_desc32_t)
#define DRM_IOCTL_MARK_BUFS32           DRM_IOW( 0x17, drm_buf_desc32_t)
#define DRM_IOCTL_INFO_BUFS32           DRM_IOWR(0x18, drm_buf_info32_t)
#define DRM_IOCTL_MAP_BUFS32            DRM_IOWR(0x19, drm_buf_map32_t)
#define DRM_IOCTL_FREE_BUFS32           DRM_IOW( 0x1a, drm_buf_free32_t)

#define DRM_IOCTL_RM_MAP32              DRM_IOW( 0x1b, drm_map32_t)

#define DRM_IOCTL_SET_SAREA_CTX32       DRM_IOW( 0x1c, drm_ctx_priv_map32_t)
#define DRM_IOCTL_GET_SAREA_CTX32       DRM_IOWR(0x1d, drm_ctx_priv_map32_t)

#define DRM_IOCTL_RES_CTX32             DRM_IOWR(0x26, drm_ctx_res32_t)
#define DRM_IOCTL_DMA32                 DRM_IOWR(0x29, drm_dma32_t)

#define DRM_IOCTL_AGP_ENABLE32          DRM_IOW( 0x32, drm_agp_mode32_t)
#define DRM_IOCTL_AGP_INFO32            DRM_IOR( 0x33, drm_agp_info32_t)
#define DRM_IOCTL_AGP_ALLOC32           DRM_IOWR(0x34, drm_agp_buffer32_t)
#define DRM_IOCTL_AGP_FREE32            DRM_IOW( 0x35, drm_agp_buffer32_t)
#define DRM_IOCTL_AGP_BIND32            DRM_IOW( 0x36, drm_agp_binding32_t)
#define DRM_IOCTL_AGP_UNBIND32          DRM_IOW( 0x37, drm_agp_binding32_t)

#define DRM_IOCTL_SG_ALLOC32            DRM_IOW( 0x38, drm_scatter_gather32_t)
#define DRM_IOCTL_SG_FREE32             DRM_IOW( 0x39, drm_scatter_gather32_t)

#define DRM_IOCTL_UPDATE_DRAW32         DRM_IOW( 0x3f, drm_update_draw32_t)

#define DRM_IOCTL_WAIT_VBLANK32         DRM_IOWR(0x3a, drm_wait_vblank32_t)

#define DRM_IOCTL_MODE_ADDFB232         DRM_IOWR(0xb8, drm_mode_fb_cmd232_t)

typedef struct drm_version_32 {
        int version_major;        /* Major version */
        int version_minor;        /* Minor version */
        int version_patchlevel;    /* Patch level */
        u32 name_len;             /* Length of name buffer */
        u32 name;                 /* Name of driver */
        u32 date_len;             /* Length of date buffer */
        u32 date;                 /* User-space buffer to hold date */
        u32 desc_len;             /* Length of desc buffer */
        u32 desc;                 /* User-space buffer to hold desc */
} drm_version32_t;

static int compat_drm_version(struct file *file, unsigned int cmd,
                              unsigned long arg)
{
        drm_version32_t v32;
        struct drm_version v;
        int err;

        if (copy_from_user(&v32, (void __user *)arg, sizeof(v32)))
                return -EFAULT;

        memset(&v, 0, sizeof(v));

        v = (struct drm_version) {
                .name_len = v32.name_len,
                .name = compat_ptr(v32.name),
                .date_len = v32.date_len,
                .date = compat_ptr(v32.date),
                .desc_len = v32.desc_len,
                .desc = compat_ptr(v32.desc),
        };
        err = drm_ioctl_kernel(file, drm_version, &v,
                               DRM_RENDER_ALLOW);
        if (err)
                return err;

        v32.version_major = v.version_major;
        v32.version_minor = v.version_minor;
        v32.version_patchlevel = v.version_patchlevel;
        v32.name_len = v.name_len;
        v32.date_len = v.date_len;
        v32.desc_len = v.desc_len;
        if (copy_to_user((void __user *)arg, &v32, sizeof(v32)))
                return -EFAULT;
        return 0;
}

typedef struct drm_unique32 {
        u32 unique_len; /* Length of unique */
        u32 unique;     /* Unique name for driver instantiation */
} drm_unique32_t;

static int compat_drm_getunique(struct file *file, unsigned int cmd,
                                unsigned long arg)
{
        drm_unique32_t uq32;
        struct drm_unique uq;
        int err;

        if (copy_from_user(&uq32, (void __user *)arg, sizeof(uq32)))
                return -EFAULT;

        memset(&uq, 0, sizeof(uq));

        uq = (struct drm_unique){
                .unique_len = uq32.unique_len,
                .unique = compat_ptr(uq32.unique),
        };

        err = drm_ioctl_kernel(file, drm_getunique, &uq, 0);
        if (err)
                return err;

        uq32.unique_len = uq.unique_len;
        if (copy_to_user((void __user *)arg, &uq32, sizeof(uq32)))
                return -EFAULT;
        return 0;
}

static int compat_drm_setunique(struct file *file, unsigned int cmd,
                                unsigned long arg)
{
        /* it's dead */
        return -EINVAL;
}

#if IS_ENABLED(CONFIG_DRM_LEGACY)
typedef struct drm_map32 {
        u32 offset;             /* Requested physical address (0 for SAREA) */
        u32 size;               /* Requested physical size (bytes) */
        enum drm_map_type type; /* Type of memory to map */
        enum drm_map_flags flags;       /* Flags */
        u32 handle;             /* User-space: "Handle" to pass to mmap() */
        int mtrr;               /* MTRR slot used */
} drm_map32_t;

static int compat_drm_getmap(struct file *file, unsigned int cmd,
                             unsigned long arg)
{
        drm_map32_t __user *argp = (void __user *)arg;
        drm_map32_t m32;
        struct drm_map map;
        int err;

        if (copy_from_user(&m32, argp, sizeof(m32)))
                return -EFAULT;

        map.offset = m32.offset;
        err = drm_ioctl_kernel(file, drm_legacy_getmap_ioctl, &map, 0);
        if (err)
                return err;

        m32.offset = map.offset;
        m32.size = map.size;
        m32.type = map.type;
        m32.flags = map.flags;
        m32.handle = ptr_to_compat((void __user *)map.handle);
        m32.mtrr = map.mtrr;
        if (copy_to_user(argp, &m32, sizeof(m32)))
                return -EFAULT;
        return 0;

}

static int compat_drm_addmap(struct file *file, unsigned int cmd,
                             unsigned long arg)
{
        drm_map32_t __user *argp = (void __user *)arg;
        drm_map32_t m32;
        struct drm_map map;
        int err;

        if (copy_from_user(&m32, argp, sizeof(m32)))
                return -EFAULT;

        map.offset = m32.offset;
        map.size = m32.size;
        map.type = m32.type;
        map.flags = m32.flags;

        err = drm_ioctl_kernel(file, drm_legacy_addmap_ioctl, &map,
                                DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY);
        if (err)
                return err;

        m32.offset = map.offset;
        m32.mtrr = map.mtrr;
        m32.handle = ptr_to_compat((void __user *)map.handle);
        if (map.handle != compat_ptr(m32.handle))
                pr_err_ratelimited("compat_drm_addmap truncated handle %p for type %d offset %x\n",
                                   map.handle, m32.type, m32.offset);

        if (copy_to_user(argp, &m32, sizeof(m32)))
                return -EFAULT;

        return 0;
}

static int compat_drm_rmmap(struct file *file, unsigned int cmd,
                            unsigned long arg)
{
        drm_map32_t __user *argp = (void __user *)arg;
        struct drm_map map;
        u32 handle;

        if (get_user(handle, &argp->handle))
                return -EFAULT;
        map.handle = compat_ptr(handle);
        return drm_ioctl_kernel(file, drm_legacy_rmmap_ioctl, &map, DRM_AUTH);
}
#endif

typedef struct drm_client32 {
        int idx;        /* Which client desired? */
        int auth;       /* Is client authenticated? */
        u32 pid;        /* Process ID */
        u32 uid;        /* User ID */
        u32 magic;      /* Magic */
        u32 iocs;       /* Ioctl count */
} drm_client32_t;

static int compat_drm_getclient(struct file *file, unsigned int cmd,
                                unsigned long arg)
{
        drm_client32_t c32;
        drm_client32_t __user *argp = (void __user *)arg;
        struct drm_client client;
        int err;

        if (copy_from_user(&c32, argp, sizeof(c32)))
                return -EFAULT;

        memset(&client, 0, sizeof(client));

        client.idx = c32.idx;

        err = drm_ioctl_kernel(file, drm_getclient, &client, 0);
        if (err)
                return err;

        c32.idx = client.idx;
        c32.auth = client.auth;
        c32.pid = client.pid;
        c32.uid = client.uid;
        c32.magic = client.magic;
        c32.iocs = client.iocs;

        if (copy_to_user(argp, &c32, sizeof(c32)))
                return -EFAULT;
        return 0;
}

typedef struct drm_stats32 {
        u32 count;
        struct {
                u32 value;
                enum drm_stat_type type;
        } data[15];
} drm_stats32_t;

static int compat_drm_getstats(struct file *file, unsigned int cmd,
                               unsigned long arg)
{
        drm_stats32_t __user *argp = (void __user *)arg;

        /* getstats is defunct, just clear */
        if (clear_user(argp, sizeof(drm_stats32_t)))
                return -EFAULT;
        return 0;
}

#if IS_ENABLED(CONFIG_DRM_LEGACY)
typedef struct drm_buf_desc32 {
        int count;               /* Number of buffers of this size */
        int size;                /* Size in bytes */
        int low_mark;            /* Low water mark */
        int high_mark;           /* High water mark */
        int flags;
        u32 agp_start;           /* Start address in the AGP aperture */
} drm_buf_desc32_t;

static int compat_drm_addbufs(struct file *file, unsigned int cmd,
                              unsigned long arg)
{
        drm_buf_desc32_t __user *argp = (void __user *)arg;
        drm_buf_desc32_t desc32;
        struct drm_buf_desc desc;
        int err;

        if (copy_from_user(&desc32, argp, sizeof(drm_buf_desc32_t)))
                return -EFAULT;

        desc = (struct drm_buf_desc){
                desc32.count, desc32.size, desc32.low_mark, desc32.high_mark,
                desc32.flags, desc32.agp_start
        };

        err = drm_ioctl_kernel(file, drm_legacy_addbufs, &desc,
                                   DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY);
        if (err)
                return err;

        desc32 = (drm_buf_desc32_t){
                desc.count, desc.size, desc.low_mark, desc.high_mark,
                desc.flags, desc.agp_start
        };
        if (copy_to_user(argp, &desc32, sizeof(drm_buf_desc32_t)))
                return -EFAULT;

        return 0;
}

static int compat_drm_markbufs(struct file *file, unsigned int cmd,
                               unsigned long arg)
{
        drm_buf_desc32_t b32;
        drm_buf_desc32_t __user *argp = (void __user *)arg;
        struct drm_buf_desc buf;

        if (copy_from_user(&b32, argp, sizeof(b32)))
                return -EFAULT;

        buf.size = b32.size;
        buf.low_mark = b32.low_mark;
        buf.high_mark = b32.high_mark;

        return drm_ioctl_kernel(file, drm_legacy_markbufs, &buf,
                                DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY);
}

typedef struct drm_buf_info32 {
        int count;              /**< Entries in list */
        u32 list;
} drm_buf_info32_t;

static int copy_one_buf32(void *data, int count, struct drm_buf_entry *from)
{
        drm_buf_info32_t *request = data;
        drm_buf_desc32_t __user *to = compat_ptr(request->list);
        drm_buf_desc32_t v = {.count = from->buf_count,
                              .size = from->buf_size,
                              .low_mark = from->low_mark,
                              .high_mark = from->high_mark};

        if (copy_to_user(to + count, &v, offsetof(drm_buf_desc32_t, flags)))
                return -EFAULT;
        return 0;
}

static int drm_legacy_infobufs32(struct drm_device *dev, void *data,
                        struct drm_file *file_priv)
{
        drm_buf_info32_t *request = data;

        return __drm_legacy_infobufs(dev, data, &request->count, copy_one_buf32);
}

static int compat_drm_infobufs(struct file *file, unsigned int cmd,
                               unsigned long arg)
{
        drm_buf_info32_t req32;
        drm_buf_info32_t __user *argp = (void __user *)arg;
        int err;

        if (copy_from_user(&req32, argp, sizeof(req32)))
                return -EFAULT;

        if (req32.count < 0)
                req32.count = 0;

        err = drm_ioctl_kernel(file, drm_legacy_infobufs32, &req32, DRM_AUTH);
        if (err)
                return err;

        if (put_user(req32.count, &argp->count))
                return -EFAULT;

        return 0;
}

typedef struct drm_buf_pub32 {
        int idx;                /**< Index into the master buffer list */
        int total;              /**< Buffer size */
        int used;               /**< Amount of buffer in use (for DMA) */
        u32 address;            /**< Address of buffer */
} drm_buf_pub32_t;

typedef struct drm_buf_map32 {
        int count;              /**< Length of the buffer list */
        u32 virtual;            /**< Mmap'd area in user-virtual */
        u32 list;               /**< Buffer information */
} drm_buf_map32_t;

static int map_one_buf32(void *data, int idx, unsigned long virtual,
                        struct drm_buf *buf)
{
        drm_buf_map32_t *request = data;
        drm_buf_pub32_t __user *to = compat_ptr(request->list) + idx;
        drm_buf_pub32_t v;

        v.idx = buf->idx;
        v.total = buf->total;
        v.used = 0;
        v.address = virtual + buf->offset;
        if (copy_to_user(to, &v, sizeof(v)))
                return -EFAULT;
        return 0;
}

static int drm_legacy_mapbufs32(struct drm_device *dev, void *data,
                       struct drm_file *file_priv)
{
        drm_buf_map32_t *request = data;
        void __user *v;
        int err = __drm_legacy_mapbufs(dev, data, &request->count,
                                    &v, map_one_buf32,
                                    file_priv);
        request->virtual = ptr_to_compat(v);
        return err;
}

static int compat_drm_mapbufs(struct file *file, unsigned int cmd,
                              unsigned long arg)
{
        drm_buf_map32_t __user *argp = (void __user *)arg;
        drm_buf_map32_t req32;
        int err;

        if (copy_from_user(&req32, argp, sizeof(req32)))
                return -EFAULT;
        if (req32.count < 0)
                return -EINVAL;

        err = drm_ioctl_kernel(file, drm_legacy_mapbufs32, &req32, DRM_AUTH);
        if (err)
                return err;

        if (put_user(req32.count, &argp->count)
            || put_user(req32.virtual, &argp->virtual))
                return -EFAULT;

        return 0;
}

typedef struct drm_buf_free32 {
        int count;
        u32 list;
} drm_buf_free32_t;

static int compat_drm_freebufs(struct file *file, unsigned int cmd,
                               unsigned long arg)
{
        drm_buf_free32_t req32;
        struct drm_buf_free request;
        drm_buf_free32_t __user *argp = (void __user *)arg;

        if (copy_from_user(&req32, argp, sizeof(req32)))
                return -EFAULT;

        request.count = req32.count;
        request.list = compat_ptr(req32.list);
        return drm_ioctl_kernel(file, drm_legacy_freebufs, &request, DRM_AUTH);
}

typedef struct drm_ctx_priv_map32 {
        unsigned int ctx_id;     /**< Context requesting private mapping */
        u32 handle;             /**< Handle of map */
} drm_ctx_priv_map32_t;

static int compat_drm_setsareactx(struct file *file, unsigned int cmd,
                                  unsigned long arg)
{
        drm_ctx_priv_map32_t req32;
        struct drm_ctx_priv_map request;
        drm_ctx_priv_map32_t __user *argp = (void __user *)arg;

        if (copy_from_user(&req32, argp, sizeof(req32)))
                return -EFAULT;

        request.ctx_id = req32.ctx_id;
        request.handle = compat_ptr(req32.handle);
        return drm_ioctl_kernel(file, drm_legacy_setsareactx, &request,
                                DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY);
}

static int compat_drm_getsareactx(struct file *file, unsigned int cmd,
                                  unsigned long arg)
{
        struct drm_ctx_priv_map req;
        drm_ctx_priv_map32_t req32;
        drm_ctx_priv_map32_t __user *argp = (void __user *)arg;
        int err;

        if (copy_from_user(&req32, argp, sizeof(req32)))
                return -EFAULT;

        req.ctx_id = req32.ctx_id;
        err = drm_ioctl_kernel(file, drm_legacy_getsareactx, &req, DRM_AUTH);
        if (err)
                return err;

        req32.handle = ptr_to_compat((void __user *)req.handle);
        if (copy_to_user(argp, &req32, sizeof(req32)))
                return -EFAULT;

        return 0;
}

typedef struct drm_ctx_res32 {
        int count;
        u32 contexts;
} drm_ctx_res32_t;

static int compat_drm_resctx(struct file *file, unsigned int cmd,
                             unsigned long arg)
{
        drm_ctx_res32_t __user *argp = (void __user *)arg;
        drm_ctx_res32_t res32;
        struct drm_ctx_res res;
        int err;

        if (copy_from_user(&res32, argp, sizeof(res32)))
                return -EFAULT;

        res.count = res32.count;
        res.contexts = compat_ptr(res32.contexts);
        err = drm_ioctl_kernel(file, drm_legacy_resctx, &res, DRM_AUTH);
        if (err)
                return err;

        res32.count = res.count;
        if (copy_to_user(argp, &res32, sizeof(res32)))
                return -EFAULT;

        return 0;
}

typedef struct drm_dma32 {
        int context;              /**< Context handle */
        int send_count;           /**< Number of buffers to send */
        u32 send_indices;         /**< List of handles to buffers */
        u32 send_sizes;           /**< Lengths of data to send */
        enum drm_dma_flags flags;                 /**< Flags */
        int request_count;        /**< Number of buffers requested */
        int request_size;         /**< Desired size for buffers */
        u32 request_indices;      /**< Buffer information */
        u32 request_sizes;
        int granted_count;        /**< Number of buffers granted */
} drm_dma32_t;

static int compat_drm_dma(struct file *file, unsigned int cmd,
                          unsigned long arg)
{
        drm_dma32_t d32;
        drm_dma32_t __user *argp = (void __user *)arg;
        struct drm_dma d;
        int err;

        if (copy_from_user(&d32, argp, sizeof(d32)))
                return -EFAULT;

        d.context = d32.context;
        d.send_count = d32.send_count;
        d.send_indices = compat_ptr(d32.send_indices);
        d.send_sizes = compat_ptr(d32.send_sizes);
        d.flags = d32.flags;
        d.request_count = d32.request_count;
        d.request_indices = compat_ptr(d32.request_indices);
        d.request_sizes = compat_ptr(d32.request_sizes);
        err = drm_ioctl_kernel(file, drm_legacy_dma_ioctl, &d, DRM_AUTH);
        if (err)
                return err;

        if (put_user(d.request_size, &argp->request_size)
            || put_user(d.granted_count, &argp->granted_count))
                return -EFAULT;

        return 0;
}
#endif

#if IS_ENABLED(CONFIG_AGP)
typedef struct drm_agp_mode32 {
        u32 mode;       /**< AGP mode */
} drm_agp_mode32_t;

static int compat_drm_agp_enable(struct file *file, unsigned int cmd,
                                 unsigned long arg)
{
        drm_agp_mode32_t __user *argp = (void __user *)arg;
        struct drm_agp_mode mode;

        if (get_user(mode.mode, &argp->mode))
                return -EFAULT;

        return drm_ioctl_kernel(file,  drm_agp_enable_ioctl, &mode,
                                DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY);
}

typedef struct drm_agp_info32 {
        int agp_version_major;
        int agp_version_minor;
        u32 mode;
        u32 aperture_base;      /* physical address */
        u32 aperture_size;      /* bytes */
        u32 memory_allowed;     /* bytes */
        u32 memory_used;

        /* PCI information */
        unsigned short id_vendor;
        unsigned short id_device;
} drm_agp_info32_t;

static int compat_drm_agp_info(struct file *file, unsigned int cmd,
                               unsigned long arg)
{
        drm_agp_info32_t __user *argp = (void __user *)arg;
        drm_agp_info32_t i32;
        struct drm_agp_info info;
        int err;

        err = drm_ioctl_kernel(file, drm_agp_info_ioctl, &info, DRM_AUTH);
        if (err)
                return err;

        i32.agp_version_major = info.agp_version_major;
        i32.agp_version_minor = info.agp_version_minor;
        i32.mode = info.mode;
        i32.aperture_base = info.aperture_base;
        i32.aperture_size = info.aperture_size;
        i32.memory_allowed = info.memory_allowed;
        i32.memory_used = info.memory_used;
        i32.id_vendor = info.id_vendor;
        i32.id_device = info.id_device;
        if (copy_to_user(argp, &i32, sizeof(i32)))
                return -EFAULT;

        return 0;
}

typedef struct drm_agp_buffer32 {
        u32 size;       /**< In bytes -- will round to page boundary */
        u32 handle;     /**< Used for binding / unbinding */
        u32 type;       /**< Type of memory to allocate */
        u32 physical;   /**< Physical used by i810 */
} drm_agp_buffer32_t;

static int compat_drm_agp_alloc(struct file *file, unsigned int cmd,
                                unsigned long arg)
{
        drm_agp_buffer32_t __user *argp = (void __user *)arg;
        drm_agp_buffer32_t req32;
        struct drm_agp_buffer request;
        int err;

        if (copy_from_user(&req32, argp, sizeof(req32)))
                return -EFAULT;

        request.size = req32.size;
        request.type = req32.type;
        err = drm_ioctl_kernel(file, drm_agp_alloc_ioctl, &request,
                                DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY);
        if (err)
                return err;

        req32.handle = request.handle;
        req32.physical = request.physical;
        if (copy_to_user(argp, &req32, sizeof(req32))) {
                drm_ioctl_kernel(file, drm_agp_free_ioctl, &request,
                                DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY);
                return -EFAULT;
        }

        return 0;
}

static int compat_drm_agp_free(struct file *file, unsigned int cmd,
                               unsigned long arg)
{
        drm_agp_buffer32_t __user *argp = (void __user *)arg;
        struct drm_agp_buffer request;

        if (get_user(request.handle, &argp->handle))
                return -EFAULT;

        return drm_ioctl_kernel(file, drm_agp_free_ioctl, &request,
                                DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY);
}

typedef struct drm_agp_binding32 {
        u32 handle;     /**< From drm_agp_buffer */
        u32 offset;     /**< In bytes -- will round to page boundary */
} drm_agp_binding32_t;

static int compat_drm_agp_bind(struct file *file, unsigned int cmd,
                               unsigned long arg)
{
        drm_agp_binding32_t __user *argp = (void __user *)arg;
        drm_agp_binding32_t req32;
        struct drm_agp_binding request;

        if (copy_from_user(&req32, argp, sizeof(req32)))
                return -EFAULT;

        request.handle = req32.handle;
        request.offset = req32.offset;
        return drm_ioctl_kernel(file, drm_agp_bind_ioctl, &request,
                                DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY);
}

static int compat_drm_agp_unbind(struct file *file, unsigned int cmd,
                                 unsigned long arg)
{
        drm_agp_binding32_t __user *argp = (void __user *)arg;
        struct drm_agp_binding request;

        if (get_user(request.handle, &argp->handle))
                return -EFAULT;

        return drm_ioctl_kernel(file, drm_agp_unbind_ioctl, &request,
                                DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY);
}
#endif /* CONFIG_AGP */

#if IS_ENABLED(CONFIG_DRM_LEGACY)
typedef struct drm_scatter_gather32 {
        u32 size;       /**< In bytes -- will round to page boundary */
        u32 handle;     /**< Used for mapping / unmapping */
} drm_scatter_gather32_t;

static int compat_drm_sg_alloc(struct file *file, unsigned int cmd,
                               unsigned long arg)
{
        drm_scatter_gather32_t __user *argp = (void __user *)arg;
        struct drm_scatter_gather request;
        int err;

        if (get_user(request.size, &argp->size))
                return -EFAULT;

        err = drm_ioctl_kernel(file, drm_legacy_sg_alloc, &request,
                                DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY);
        if (err)
                return err;

        /* XXX not sure about the handle conversion here... */
        if (put_user(request.handle >> PAGE_SHIFT, &argp->handle))
                return -EFAULT;

        return 0;
}

static int compat_drm_sg_free(struct file *file, unsigned int cmd,
                              unsigned long arg)
{
        drm_scatter_gather32_t __user *argp = (void __user *)arg;
        struct drm_scatter_gather request;
        unsigned long x;

        if (get_user(x, &argp->handle))
                return -EFAULT;
        request.handle = x << PAGE_SHIFT;
        return drm_ioctl_kernel(file, drm_legacy_sg_free, &request,
                                DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY);
}
#endif
#if defined(CONFIG_X86)
typedef struct drm_update_draw32 {
        drm_drawable_t handle;
        unsigned int type;
        unsigned int num;
        /* 64-bit version has a 32-bit pad here */
        u64 data;       /**< Pointer */
} __attribute__((packed)) drm_update_draw32_t;

static int compat_drm_update_draw(struct file *file, unsigned int cmd,
                                  unsigned long arg)
{
        /* update_draw is defunct */
        return 0;
}
#endif

struct drm_wait_vblank_request32 {
        enum drm_vblank_seq_type type;
        unsigned int sequence;
        u32 signal;
};

struct drm_wait_vblank_reply32 {
        enum drm_vblank_seq_type type;
        unsigned int sequence;
        s32 tval_sec;
        s32 tval_usec;
};

typedef union drm_wait_vblank32 {
        struct drm_wait_vblank_request32 request;
        struct drm_wait_vblank_reply32 reply;
} drm_wait_vblank32_t;

static int compat_drm_wait_vblank(struct file *file, unsigned int cmd,
                                  unsigned long arg)
{
        drm_wait_vblank32_t __user *argp = (void __user *)arg;
        drm_wait_vblank32_t req32;
        union drm_wait_vblank req;
        int err;

        if (copy_from_user(&req32, argp, sizeof(req32)))
                return -EFAULT;

        memset(&req, 0, sizeof(req));

        req.request.type = req32.request.type;
        req.request.sequence = req32.request.sequence;
        req.request.signal = req32.request.signal;
        err = drm_ioctl_kernel(file, drm_wait_vblank_ioctl, &req, DRM_UNLOCKED);
        if (err)
                return err;

        req32.reply.type = req.reply.type;
        req32.reply.sequence = req.reply.sequence;
        req32.reply.tval_sec = req.reply.tval_sec;
        req32.reply.tval_usec = req.reply.tval_usec;
        if (copy_to_user(argp, &req32, sizeof(req32)))
                return -EFAULT;

        return 0;
}

#if defined(CONFIG_X86)
typedef struct drm_mode_fb_cmd232 {
        u32 fb_id;
        u32 width;
        u32 height;
        u32 pixel_format;
        u32 flags;
        u32 handles[4];
        u32 pitches[4];
        u32 offsets[4];
        u64 modifier[4];
} __attribute__((packed)) drm_mode_fb_cmd232_t;

static int compat_drm_mode_addfb2(struct file *file, unsigned int cmd,
                                  unsigned long arg)
{
        struct drm_mode_fb_cmd232 __user *argp = (void __user *)arg;
        struct drm_mode_fb_cmd2 req64;
        int err;

        memset(&req64, 0, sizeof(req64));

        if (copy_from_user(&req64, argp,
                           offsetof(drm_mode_fb_cmd232_t, modifier)))
                return -EFAULT;

        if (copy_from_user(&req64.modifier, &argp->modifier,
                           sizeof(req64.modifier)))
                return -EFAULT;

        err = drm_ioctl_kernel(file, drm_mode_addfb2, &req64, 0);
        if (err)
                return err;

        if (put_user(req64.fb_id, &argp->fb_id))
                return -EFAULT;

        return 0;
}
#endif

static struct {
        drm_ioctl_compat_t *fn;
        char *name;
} drm_compat_ioctls[] = {
#define DRM_IOCTL32_DEF(n, f) [DRM_IOCTL_NR(n##32)] = {.fn = f, .name = #n}
        DRM_IOCTL32_DEF(DRM_IOCTL_VERSION, compat_drm_version),
        DRM_IOCTL32_DEF(DRM_IOCTL_GET_UNIQUE, compat_drm_getunique),
#if IS_ENABLED(CONFIG_DRM_LEGACY)
        DRM_IOCTL32_DEF(DRM_IOCTL_GET_MAP, compat_drm_getmap),
#endif
        DRM_IOCTL32_DEF(DRM_IOCTL_GET_CLIENT, compat_drm_getclient),
        DRM_IOCTL32_DEF(DRM_IOCTL_GET_STATS, compat_drm_getstats),
        DRM_IOCTL32_DEF(DRM_IOCTL_SET_UNIQUE, compat_drm_setunique),
#if IS_ENABLED(CONFIG_DRM_LEGACY)
        DRM_IOCTL32_DEF(DRM_IOCTL_ADD_MAP, compat_drm_addmap),
        DRM_IOCTL32_DEF(DRM_IOCTL_ADD_BUFS, compat_drm_addbufs),
        DRM_IOCTL32_DEF(DRM_IOCTL_MARK_BUFS, compat_drm_markbufs),
        DRM_IOCTL32_DEF(DRM_IOCTL_INFO_BUFS, compat_drm_infobufs),
        DRM_IOCTL32_DEF(DRM_IOCTL_MAP_BUFS, compat_drm_mapbufs),
        DRM_IOCTL32_DEF(DRM_IOCTL_FREE_BUFS, compat_drm_freebufs),
        DRM_IOCTL32_DEF(DRM_IOCTL_RM_MAP, compat_drm_rmmap),
        DRM_IOCTL32_DEF(DRM_IOCTL_SET_SAREA_CTX, compat_drm_setsareactx),
        DRM_IOCTL32_DEF(DRM_IOCTL_GET_SAREA_CTX, compat_drm_getsareactx),
        DRM_IOCTL32_DEF(DRM_IOCTL_RES_CTX, compat_drm_resctx),
        DRM_IOCTL32_DEF(DRM_IOCTL_DMA, compat_drm_dma),
#endif
#if IS_ENABLED(CONFIG_AGP)
        DRM_IOCTL32_DEF(DRM_IOCTL_AGP_ENABLE, compat_drm_agp_enable),
        DRM_IOCTL32_DEF(DRM_IOCTL_AGP_INFO, compat_drm_agp_info),
        DRM_IOCTL32_DEF(DRM_IOCTL_AGP_ALLOC, compat_drm_agp_alloc),
        DRM_IOCTL32_DEF(DRM_IOCTL_AGP_FREE, compat_drm_agp_free),
        DRM_IOCTL32_DEF(DRM_IOCTL_AGP_BIND, compat_drm_agp_bind),
        DRM_IOCTL32_DEF(DRM_IOCTL_AGP_UNBIND, compat_drm_agp_unbind),
#endif
#if IS_ENABLED(CONFIG_DRM_LEGACY)
        DRM_IOCTL32_DEF(DRM_IOCTL_SG_ALLOC, compat_drm_sg_alloc),
        DRM_IOCTL32_DEF(DRM_IOCTL_SG_FREE, compat_drm_sg_free),
#endif
#if defined(CONFIG_X86) || defined(CONFIG_IA64)
        DRM_IOCTL32_DEF(DRM_IOCTL_UPDATE_DRAW, compat_drm_update_draw),
#endif
        DRM_IOCTL32_DEF(DRM_IOCTL_WAIT_VBLANK, compat_drm_wait_vblank),
#if defined(CONFIG_X86) || defined(CONFIG_IA64)
        DRM_IOCTL32_DEF(DRM_IOCTL_MODE_ADDFB2, compat_drm_mode_addfb2),
#endif
};

/**
 * drm_compat_ioctl - 32bit IOCTL compatibility handler for DRM drivers
 * @filp: file this ioctl is called on
 * @cmd: ioctl cmd number
 * @arg: user argument
 *
 * Compatibility handler for 32 bit userspace running on 64 kernels. All actual
 * IOCTL handling is forwarded to drm_ioctl(), while marshalling structures as
 * appropriate. Note that this only handles DRM core IOCTLs, if the driver has
 * botched IOCTL itself, it must handle those by wrapping this function.
 *
 * Returns:
 * Zero on success, negative error code on failure.
 */
long drm_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
        unsigned int nr = DRM_IOCTL_NR(cmd);
        struct drm_file *file_priv = filp->private_data;
        drm_ioctl_compat_t *fn;
        int ret;

        /* Assume that ioctls without an explicit compat routine will just
         * work.  This may not always be a good assumption, but it's better
         * than always failing.
         */
        if (nr >= ARRAY_SIZE(drm_compat_ioctls))
                return drm_ioctl(filp, cmd, arg);

        fn = drm_compat_ioctls[nr].fn;
        if (!fn)
                return drm_ioctl(filp, cmd, arg);

        DRM_DEBUG("comm=\"%s\", pid=%d, dev=0x%lx, auth=%d, %s\n",
                  current->comm, task_pid_nr(current),
                  (long)old_encode_dev(file_priv->minor->kdev->devt),
                  file_priv->authenticated,
                  drm_compat_ioctls[nr].name);
        ret = (*fn)(filp, cmd, arg);
        if (ret)
                DRM_DEBUG("ret = %d\n", ret);
        return ret;

}
EXPORT_SYMBOL(drm_compat_ioctl);