/*
 * Internal Header for the Direct Rendering Manager
 *
 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
 * Copyright (c) 2009-2010, Code Aurora Forum.
 * All rights reserved.
 *
 * Author: Rickard E. (Rik) Faith <faith@valinux.com>
 * Author: Gareth Hughes <gareth@valinux.com>
 *
 * 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.
 */

#ifndef _DRM_P_H_
#define _DRM_P_H_

#include <linux/agp_backend.h>
#include <linux/cdev.h>
#include <linux/dma-mapping.h>
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/highmem.h>
#include <linux/idr.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/kref.h>
#include <linux/miscdevice.h>
#include <linux/mm.h>
#include <linux/mutex.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
#include <linux/poll.h>
#include <linux/ratelimit.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/vmalloc.h>
#include <linux/workqueue.h>

#include <asm/mman.h>
#include <asm/pgalloc.h>
#include <asm/uaccess.h>

#include <uapi/drm/drm.h>
#include <uapi/drm/drm_mode.h>

#include <drm/drm_agpsupport.h>
#include <drm/drm_crtc.h>
#include <drm/drm_global.h>
#include <drm/drm_hashtab.h>
#include <drm/drm_mem_util.h>
#include <drm/drm_mm.h>
#include <drm/drm_os_linux.h>
#include <drm/drm_sarea.h>
#include <drm/drm_vma_manager.h>

struct module;

struct drm_file;
struct drm_device;
struct drm_agp_head;
struct drm_local_map;
struct drm_device_dma;
struct drm_dma_handle;
struct drm_gem_object;

struct device_node;
struct videomode;
struct reservation_object;
struct dma_buf_attachment;

/*
 * 4 debug categories are defined:
 *
 * CORE: Used in the generic drm code: drm_ioctl.c, drm_mm.c, drm_memory.c, ...
 *       This is the category used by the DRM_DEBUG() macro.
 *
 * DRIVER: Used in the vendor specific part of the driver: i915, radeon, ...
 *         This is the category used by the DRM_DEBUG_DRIVER() macro.
 *
 * KMS: used in the modesetting code.
 *      This is the category used by the DRM_DEBUG_KMS() macro.
 *
 * PRIME: used in the prime code.
 *        This is the category used by the DRM_DEBUG_PRIME() macro.
 *
 * ATOMIC: used in the atomic code.
 *        This is the category used by the DRM_DEBUG_ATOMIC() macro.
 *
 * VBL: used for verbose debug message in the vblank code
 *        This is the category used by the DRM_DEBUG_VBL() macro.
 *
 * Enabling verbose debug messages is done through the drm.debug parameter,
 * each category being enabled by a bit.
 *
 * drm.debug=0x1 will enable CORE messages
 * drm.debug=0x2 will enable DRIVER messages
 * drm.debug=0x3 will enable CORE and DRIVER messages
 * ...
 * drm.debug=0x3f will enable all messages
 *
 * An interesting feature is that it's possible to enable verbose logging at
 * run-time by echoing the debug value in its sysfs node:
 *   # echo 0xf > /sys/module/drm/parameters/debug
 */
#define DRM_UT_CORE             0x01
#define DRM_UT_DRIVER           0x02
#define DRM_UT_KMS              0x04
#define DRM_UT_PRIME            0x08
#define DRM_UT_ATOMIC           0x10
#define DRM_UT_VBL              0x20

extern __printf(2, 3)
void drm_ut_debug_printk(const char *function_name,
                         const char *format, ...);
extern __printf(1, 2)
void drm_err(const char *format, ...);

/***********************************************************************/
/** \name DRM template customization defaults */
/*@{*/

/* driver capabilities and requirements mask */
#define DRIVER_USE_AGP                  0x1
#define DRIVER_PCI_DMA                  0x8
#define DRIVER_SG                       0x10
#define DRIVER_HAVE_DMA                 0x20
#define DRIVER_HAVE_IRQ                 0x40
#define DRIVER_IRQ_SHARED               0x80
#define DRIVER_GEM                      0x1000
#define DRIVER_MODESET                  0x2000
#define DRIVER_PRIME                    0x4000
#define DRIVER_RENDER                   0x8000
#define DRIVER_ATOMIC                   0x10000
#define DRIVER_KMS_LEGACY_CONTEXT       0x20000

/***********************************************************************/
/** \name Macros to make printk easier */
/*@{*/

/**
 * Error output.
 *
 * \param fmt printf() like format string.
 * \param arg arguments
 */
#define DRM_ERROR(fmt, ...)                             \
        drm_err(fmt, ##__VA_ARGS__)

/**
 * Rate limited error output.  Like DRM_ERROR() but won't flood the log.
 *
 * \param fmt printf() like format string.
 * \param arg arguments
 */
#define DRM_ERROR_RATELIMITED(fmt, ...)                         \
({                                                                      \
        static DEFINE_RATELIMIT_STATE(_rs,                              \
                                      DEFAULT_RATELIMIT_INTERVAL,       \
                                      DEFAULT_RATELIMIT_BURST);         \
                                                                        \
        if (__ratelimit(&_rs))                                          \
                drm_err(fmt, ##__VA_ARGS__);                            \
})

#define DRM_INFO(fmt, ...)                              \
        printk(KERN_INFO "[" DRM_NAME "] " fmt, ##__VA_ARGS__)

#define DRM_INFO_ONCE(fmt, ...)                         \
        printk_once(KERN_INFO "[" DRM_NAME "] " fmt, ##__VA_ARGS__)

/**
 * Debug output.
 *
 * \param fmt printf() like format string.
 * \param arg arguments
 */
#define DRM_DEBUG(fmt, args...)                                         \
        do {                                                            \
                if (unlikely(drm_debug & DRM_UT_CORE))                  \
                        drm_ut_debug_printk(__func__, fmt, ##args);     \
        } while (0)

#define DRM_DEBUG_DRIVER(fmt, args...)                                  \
        do {                                                            \
                if (unlikely(drm_debug & DRM_UT_DRIVER))                \
                        drm_ut_debug_printk(__func__, fmt, ##args);     \
        } while (0)
#define DRM_DEBUG_KMS(fmt, args...)                                     \
        do {                                                            \
                if (unlikely(drm_debug & DRM_UT_KMS))                   \
                        drm_ut_debug_printk(__func__, fmt, ##args);     \
        } while (0)
#define DRM_DEBUG_PRIME(fmt, args...)                                   \
        do {                                                            \
                if (unlikely(drm_debug & DRM_UT_PRIME))                 \
                        drm_ut_debug_printk(__func__, fmt, ##args);     \
        } while (0)
#define DRM_DEBUG_ATOMIC(fmt, args...)                                  \
        do {                                                            \
                if (unlikely(drm_debug & DRM_UT_ATOMIC))                \
                        drm_ut_debug_printk(__func__, fmt, ##args);     \
        } while (0)
#define DRM_DEBUG_VBL(fmt, args...)                                     \
        do {                                                            \
                if (unlikely(drm_debug & DRM_UT_VBL))                   \
                        drm_ut_debug_printk(__func__, fmt, ##args);     \
        } while (0)

/*@}*/

/***********************************************************************/
/** \name Internal types and structures */
/*@{*/

#define DRM_IF_VERSION(maj, min) (maj << 16 | min)

/**
 * Ioctl function type.
 *
 * \param inode device inode.
 * \param file_priv DRM file private pointer.
 * \param cmd command.
 * \param arg argument.
 */
typedef int drm_ioctl_t(struct drm_device *dev, void *data,
                        struct drm_file *file_priv);

typedef int drm_ioctl_compat_t(struct file *filp, unsigned int cmd,
                               unsigned long arg);

#define DRM_IOCTL_NR(n)                _IOC_NR(n)
#define DRM_MAJOR       226

#define DRM_AUTH        0x1
#define DRM_MASTER      0x2
#define DRM_ROOT_ONLY   0x4
#define DRM_CONTROL_ALLOW 0x8
#define DRM_UNLOCKED    0x10
#define DRM_RENDER_ALLOW 0x20

struct drm_ioctl_desc {
        unsigned int cmd;
        int flags;
        drm_ioctl_t *func;
        const char *name;
};

/**
 * Creates a driver or general drm_ioctl_desc array entry for the given
 * ioctl, for use by drm_ioctl().
 */

#define DRM_IOCTL_DEF_DRV(ioctl, _func, _flags)                         \
        [DRM_IOCTL_NR(DRM_IOCTL_##ioctl) - DRM_COMMAND_BASE] = {        \
                .cmd = DRM_IOCTL_##ioctl,                               \
                .func = _func,                                          \
                .flags = _flags,                                        \
                .name = #ioctl                                          \
         }

/* Event queued up for userspace to read */
struct drm_pending_event {
        struct drm_event *event;
        struct list_head link;
        struct list_head pending_link;
        struct drm_file *file_priv;
        pid_t pid; /* pid of requester, no guarantee it's valid by the time
                      we deliver the event, for tracing only */
        void (*destroy)(struct drm_pending_event *event);
};

/* initial implementaton using a linked list - todo hashtab */
struct drm_prime_file_private {
        struct list_head head;
        struct mutex lock;
};

/** File private data */
struct drm_file {
        unsigned authenticated :1;
        /* Whether we're master for a minor. Protected by master_mutex */
        unsigned is_master :1;
        /* true when the client has asked us to expose stereo 3D mode flags */
        unsigned stereo_allowed :1;
        /*
         * true if client understands CRTC primary planes and cursor planes
         * in the plane list
         */
        unsigned universal_planes:1;
        /* true if client understands atomic properties */
        unsigned atomic:1;
        /*
         * This client is allowed to gain master privileges for @master.
         * Protected by struct drm_device::master_mutex.
         */
        unsigned allowed_master:1;

        struct pid *pid;
        kuid_t uid;
        drm_magic_t magic;
        struct list_head lhead;
        struct drm_minor *minor;
        unsigned long lock_count;

        /** Mapping of mm object handles to object pointers. */
        struct idr object_idr;
        /** Lock for synchronization of access to object_idr. */
        spinlock_t table_lock;

        struct file *filp;
        void *driver_priv;

        struct drm_master *master; /* master this node is currently associated with
                                      N.B. not always minor->master */
        /**
         * fbs - List of framebuffers associated with this file.
         *
         * Protected by fbs_lock. Note that the fbs list holds a reference on
         * the fb object to prevent it from untimely disappearing.
         */
        struct list_head fbs;
        struct mutex fbs_lock;

        /** User-created blob properties; this retains a reference on the
         *  property. */
        struct list_head blobs;

        wait_queue_head_t event_wait;
        struct list_head pending_event_list;
        struct list_head event_list;
        int event_space;

        struct mutex event_read_lock;

        struct drm_prime_file_private prime;
};

/**
 * Lock data.
 */
struct drm_lock_data {
        struct drm_hw_lock *hw_lock;    /**< Hardware lock */
        /** Private of lock holder's file (NULL=kernel) */
        struct drm_file *file_priv;
        wait_queue_head_t lock_queue;   /**< Queue of blocked processes */
        unsigned long lock_time;        /**< Time of last lock in jiffies */
        spinlock_t spinlock;
        uint32_t kernel_waiters;
        uint32_t user_waiters;
        int idle_has_lock;
};

/**
 * struct drm_master - drm master structure
 *
 * @refcount: Refcount for this master object.
 * @minor: Link back to minor char device we are master for. Immutable.
 * @unique: Unique identifier: e.g. busid. Protected by drm_global_mutex.
 * @unique_len: Length of unique field. Protected by drm_global_mutex.
 * @magic_map: Map of used authentication tokens. Protected by struct_mutex.
 * @lock: DRI lock information.
 * @driver_priv: Pointer to driver-private information.
 */
struct drm_master {
        struct kref refcount;
        struct drm_minor *minor;
        char *unique;
        int unique_len;
        struct idr magic_map;
        struct drm_lock_data lock;
        void *driver_priv;
};

/* Size of ringbuffer for vblank timestamps. Just double-buffer
 * in initial implementation.
 */
#define DRM_VBLANKTIME_RBSIZE 2

/* Flags and return codes for get_vblank_timestamp() driver function. */
#define DRM_CALLED_FROM_VBLIRQ 1
#define DRM_VBLANKTIME_SCANOUTPOS_METHOD (1 << 0)
#define DRM_VBLANKTIME_IN_VBLANK         (1 << 1)

/* get_scanout_position() return flags */
#define DRM_SCANOUTPOS_VALID        (1 << 0)
#define DRM_SCANOUTPOS_IN_VBLANK    (1 << 1)
#define DRM_SCANOUTPOS_ACCURATE     (1 << 2)

/**
 * DRM driver structure. This structure represent the common code for
 * a family of cards. There will one drm_device for each card present
 * in this family
 */
struct drm_driver {
        int (*load) (struct drm_device *, unsigned long flags);
        int (*firstopen) (struct drm_device *);
        int (*open) (struct drm_device *, struct drm_file *);
        void (*preclose) (struct drm_device *, struct drm_file *file_priv);
        void (*postclose) (struct drm_device *, struct drm_file *);
        void (*lastclose) (struct drm_device *);
        int (*unload) (struct drm_device *);
        int (*suspend) (struct drm_device *, pm_message_t state);
        int (*resume) (struct drm_device *);
        int (*dma_ioctl) (struct drm_device *dev, void *data, struct drm_file *file_priv);
        int (*dma_quiescent) (struct drm_device *);
        int (*context_dtor) (struct drm_device *dev, int context);
        int (*set_busid)(struct drm_device *dev, struct drm_master *master);

        /**
         * get_vblank_counter - get raw hardware vblank counter
         * @dev: DRM device
         * @pipe: counter to fetch
         *
         * Driver callback for fetching a raw hardware vblank counter for @crtc.
         * If a device doesn't have a hardware counter, the driver can simply
         * return the value of drm_vblank_count. The DRM core will account for
         * missed vblank events while interrupts where disabled based on system
         * timestamps.
         *
         * Wraparound handling and loss of events due to modesetting is dealt
         * with in the DRM core code.
         *
         * RETURNS
         * Raw vblank counter value.
         */
        u32 (*get_vblank_counter) (struct drm_device *dev, unsigned int pipe);

        /**
         * enable_vblank - enable vblank interrupt events
         * @dev: DRM device
         * @pipe: which irq to enable
         *
         * Enable vblank interrupts for @crtc.  If the device doesn't have
         * a hardware vblank counter, this routine should be a no-op, since
         * interrupts will have to stay on to keep the count accurate.
         *
         * RETURNS
         * Zero on success, appropriate errno if the given @crtc's vblank
         * interrupt cannot be enabled.
         */
        int (*enable_vblank) (struct drm_device *dev, unsigned int pipe);

        /**
         * disable_vblank - disable vblank interrupt events
         * @dev: DRM device
         * @pipe: which irq to enable
         *
         * Disable vblank interrupts for @crtc.  If the device doesn't have
         * a hardware vblank counter, this routine should be a no-op, since
         * interrupts will have to stay on to keep the count accurate.
         */
        void (*disable_vblank) (struct drm_device *dev, unsigned int pipe);

        /**
         * Called by \c drm_device_is_agp.  Typically used to determine if a
         * card is really attached to AGP or not.
         *
         * \param dev  DRM device handle
         *
         * \returns
         * One of three values is returned depending on whether or not the
         * card is absolutely \b not AGP (return of 0), absolutely \b is AGP
         * (return of 1), or may or may not be AGP (return of 2).
         */
        int (*device_is_agp) (struct drm_device *dev);

        /**
         * Called by vblank timestamping code.
         *
         * Return the current display scanout position from a crtc, and an
         * optional accurate ktime_get timestamp of when position was measured.
         *
         * \param dev  DRM device.
         * \param pipe Id of the crtc to query.
         * \param flags Flags from the caller (DRM_CALLED_FROM_VBLIRQ or 0).
         * \param *vpos Target location for current vertical scanout position.
         * \param *hpos Target location for current horizontal scanout position.
         * \param *stime Target location for timestamp taken immediately before
         *               scanout position query. Can be NULL to skip timestamp.
         * \param *etime Target location for timestamp taken immediately after
         *               scanout position query. Can be NULL to skip timestamp.
         * \param mode Current display timings.
         *
         * Returns vpos as a positive number while in active scanout area.
         * Returns vpos as a negative number inside vblank, counting the number
         * of scanlines to go until end of vblank, e.g., -1 means "one scanline
         * until start of active scanout / end of vblank."
         *
         * \return Flags, or'ed together as follows:
         *
         * DRM_SCANOUTPOS_VALID = Query successful.
         * DRM_SCANOUTPOS_INVBL = Inside vblank.
         * DRM_SCANOUTPOS_ACCURATE = Returned position is accurate. A lack of
         * this flag means that returned position may be offset by a constant
         * but unknown small number of scanlines wrt. real scanout position.
         *
         */
        int (*get_scanout_position) (struct drm_device *dev, unsigned int pipe,
                                     unsigned int flags, int *vpos, int *hpos,
                                     ktime_t *stime, ktime_t *etime,
                                     const struct drm_display_mode *mode);

        /**
         * Called by \c drm_get_last_vbltimestamp. Should return a precise
         * timestamp when the most recent VBLANK interval ended or will end.
         *
         * Specifically, the timestamp in @vblank_time should correspond as
         * closely as possible to the time when the first video scanline of
         * the video frame after the end of VBLANK will start scanning out,
         * the time immediately after end of the VBLANK interval. If the
         * @crtc is currently inside VBLANK, this will be a time in the future.
         * If the @crtc is currently scanning out a frame, this will be the
         * past start time of the current scanout. This is meant to adhere
         * to the OpenML OML_sync_control extension specification.
         *
         * \param dev dev DRM device handle.
         * \param pipe crtc for which timestamp should be returned.
         * \param *max_error Maximum allowable timestamp error in nanoseconds.
         *                   Implementation should strive to provide timestamp
         *                   with an error of at most *max_error nanoseconds.
         *                   Returns true upper bound on error for timestamp.
         * \param *vblank_time Target location for returned vblank timestamp.
         * \param flags 0 = Defaults, no special treatment needed.
         * \param       DRM_CALLED_FROM_VBLIRQ = Function is called from vblank
         *              irq handler. Some drivers need to apply some workarounds
         *              for gpu-specific vblank irq quirks if flag is set.
         *
         * \returns
         * Zero if timestamping isn't supported in current display mode or a
         * negative number on failure. A positive status code on success,
         * which describes how the vblank_time timestamp was computed.
         */
        int (*get_vblank_timestamp) (struct drm_device *dev, unsigned int pipe,
                                     int *max_error,
                                     struct timeval *vblank_time,
                                     unsigned flags);

        /* these have to be filled in */

        irqreturn_t(*irq_handler) (int irq, void *arg);
        void (*irq_preinstall) (struct drm_device *dev);
        int (*irq_postinstall) (struct drm_device *dev);
        void (*irq_uninstall) (struct drm_device *dev);

        /* Master routines */
        int (*master_create)(struct drm_device *dev, struct drm_master *master);
        void (*master_destroy)(struct drm_device *dev, struct drm_master *master);
        /**
         * master_set is called whenever the minor master is set.
         * master_drop is called whenever the minor master is dropped.
         */

        int (*master_set)(struct drm_device *dev, struct drm_file *file_priv,
                          bool from_open);
        void (*master_drop)(struct drm_device *dev, struct drm_file *file_priv,
                            bool from_release);

        int (*debugfs_init)(struct drm_minor *minor);
        void (*debugfs_cleanup)(struct drm_minor *minor);

        /**
         * Driver-specific constructor for drm_gem_objects, to set up
         * obj->driver_private.
         *
         * Returns 0 on success.
         */
        void (*gem_free_object) (struct drm_gem_object *obj);
        int (*gem_open_object) (struct drm_gem_object *, struct drm_file *);
        void (*gem_close_object) (struct drm_gem_object *, struct drm_file *);

        /**
         * Hook for allocating the GEM object struct, for use by core
         * helpers.
         */
        struct drm_gem_object *(*gem_create_object)(struct drm_device *dev,
                                                    size_t size);

        /* prime: */
        /* export handle -> fd (see drm_gem_prime_handle_to_fd() helper) */
        int (*prime_handle_to_fd)(struct drm_device *dev, struct drm_file *file_priv,
                                uint32_t handle, uint32_t flags, int *prime_fd);
        /* import fd -> handle (see drm_gem_prime_fd_to_handle() helper) */
        int (*prime_fd_to_handle)(struct drm_device *dev, struct drm_file *file_priv,
                                int prime_fd, uint32_t *handle);
        /* export GEM -> dmabuf */
        struct dma_buf * (*gem_prime_export)(struct drm_device *dev,
                                struct drm_gem_object *obj, int flags);
        /* import dmabuf -> GEM */
        struct drm_gem_object * (*gem_prime_import)(struct drm_device *dev,
                                struct dma_buf *dma_buf);
        /* low-level interface used by drm_gem_prime_{import,export} */
        int (*gem_prime_pin)(struct drm_gem_object *obj);
        void (*gem_prime_unpin)(struct drm_gem_object *obj);
        struct reservation_object * (*gem_prime_res_obj)(
                                struct drm_gem_object *obj);
        struct sg_table *(*gem_prime_get_sg_table)(struct drm_gem_object *obj);
        struct drm_gem_object *(*gem_prime_import_sg_table)(
                                struct drm_device *dev,
                                struct dma_buf_attachment *attach,
                                struct sg_table *sgt);
        void *(*gem_prime_vmap)(struct drm_gem_object *obj);
        void (*gem_prime_vunmap)(struct drm_gem_object *obj, void *vaddr);
        int (*gem_prime_mmap)(struct drm_gem_object *obj,
                                struct vm_area_struct *vma);

        /* vga arb irq handler */
        void (*vgaarb_irq)(struct drm_device *dev, bool state);

        /* dumb alloc support */
        int (*dumb_create)(struct drm_file *file_priv,
                           struct drm_device *dev,
                           struct drm_mode_create_dumb *args);
        int (*dumb_map_offset)(struct drm_file *file_priv,
                               struct drm_device *dev, uint32_t handle,
                               uint64_t *offset);
        int (*dumb_destroy)(struct drm_file *file_priv,
                            struct drm_device *dev,
                            uint32_t handle);

        /* Driver private ops for this object */
        const struct vm_operations_struct *gem_vm_ops;

        int major;
        int minor;
        int patchlevel;
        char *name;
        char *desc;
        char *date;

        u32 driver_features;
        int dev_priv_size;
        const struct drm_ioctl_desc *ioctls;
        int num_ioctls;
        const struct file_operations *fops;

        /* List of devices hanging off this driver with stealth attach. */
        struct list_head legacy_dev_list;
};

enum drm_minor_type {
        DRM_MINOR_LEGACY,
        DRM_MINOR_CONTROL,
        DRM_MINOR_RENDER,
        DRM_MINOR_CNT,
};

/**
 * Info file list entry. This structure represents a debugfs or proc file to
 * be created by the drm core
 */
struct drm_info_list {
        const char *name; /** file name */
        int (*show)(struct seq_file*, void*); /** show callback */
        u32 driver_features; /**< Required driver features for this entry */
        void *data;
};

/**
 * debugfs node structure. This structure represents a debugfs file.
 */
struct drm_info_node {
        struct list_head list;
        struct drm_minor *minor;
        const struct drm_info_list *info_ent;
        struct dentry *dent;
};

/**
 * DRM minor structure. This structure represents a drm minor number.
 */
struct drm_minor {
        int index;                      /**< Minor device number */
        int type;                       /**< Control or render */
        struct device *kdev;            /**< Linux device */
        struct drm_device *dev;

        struct dentry *debugfs_root;

        struct list_head debugfs_list;
        struct mutex debugfs_lock; /* Protects debugfs_list. */

        /* currently active master for this node. Protected by master_mutex */
        struct drm_master *master;
};


struct drm_pending_vblank_event {
        struct drm_pending_event base;
        unsigned int pipe;
        struct drm_event_vblank event;
};

struct drm_vblank_crtc {
        struct drm_device *dev;         /* pointer to the drm_device */
        wait_queue_head_t queue;        /**< VBLANK wait queue */
        struct timer_list disable_timer;                /* delayed disable timer */

        /* vblank counter, protected by dev->vblank_time_lock for writes */
        u32 count;
        /* vblank timestamps, protected by dev->vblank_time_lock for writes */
        struct timeval time[DRM_VBLANKTIME_RBSIZE];

        atomic_t refcount;              /* number of users of vblank interruptsper crtc */
        u32 last;                       /* protected by dev->vbl_lock, used */
                                        /* for wraparound handling */
        u32 last_wait;                  /* Last vblank seqno waited per CRTC */
        unsigned int inmodeset;         /* Display driver is setting mode */
        unsigned int pipe;              /* crtc index */
        int framedur_ns;                /* frame/field duration in ns */
        int linedur_ns;                 /* line duration in ns */
        bool enabled;                   /* so we don't call enable more than
                                           once per disable */
};

/**
 * DRM device structure. This structure represent a complete card that
 * may contain multiple heads.
 */
struct drm_device {
        struct list_head legacy_dev_list;/**< list of devices per driver for stealth attach cleanup */
        int if_version;                 /**< Highest interface version set */

        /** \name Lifetime Management */
        /*@{ */
        struct kref ref;                /**< Object ref-count */
        struct device *dev;             /**< Device structure of bus-device */
        struct drm_driver *driver;      /**< DRM driver managing the device */
        void *dev_private;              /**< DRM driver private data */
        struct drm_minor *control;              /**< Control node */
        struct drm_minor *primary;              /**< Primary node */
        struct drm_minor *render;               /**< Render node */
        atomic_t unplugged;                     /**< Flag whether dev is dead */
        struct inode *anon_inode;               /**< inode for private address-space */
        char *unique;                           /**< unique name of the device */
        /*@} */

        /** \name Locks */
        /*@{ */
        struct mutex struct_mutex;      /**< For others */
        struct mutex master_mutex;      /**< For drm_minor::master and drm_file::is_master */
        /*@} */

        /** \name Usage Counters */
        /*@{ */
        int open_count;                 /**< Outstanding files open, protected by drm_global_mutex. */
        spinlock_t buf_lock;            /**< For drm_device::buf_use and a few other things. */
        int buf_use;                    /**< Buffers in use -- cannot alloc */
        atomic_t buf_alloc;             /**< Buffer allocation in progress */
        /*@} */

        struct list_head filelist;

        /** \name Memory management */
        /*@{ */
        struct list_head maplist;       /**< Linked list of regions */
        struct drm_open_hash map_hash;  /**< User token hash table for maps */

        /** \name Context handle management */
        /*@{ */
        struct list_head ctxlist;       /**< Linked list of context handles */
        struct mutex ctxlist_mutex;     /**< For ctxlist */

        struct idr ctx_idr;

        struct list_head vmalist;       /**< List of vmas (for debugging) */

        /*@} */

        /** \name DMA support */
        /*@{ */
        struct drm_device_dma *dma;             /**< Optional pointer for DMA support */
        /*@} */

        /** \name Context support */
        /*@{ */

        __volatile__ long context_flag; /**< Context swapping flag */
        int last_context;               /**< Last current context */
        /*@} */

        /** \name VBLANK IRQ support */
        /*@{ */
        bool irq_enabled;
        int irq;

        /*
         * At load time, disabling the vblank interrupt won't be allowed since
         * old clients may not call the modeset ioctl and therefore misbehave.
         * Once the modeset ioctl *has* been called though, we can safely
         * disable them when unused.
         */
        bool vblank_disable_allowed;

        /*
         * If true, vblank interrupt will be disabled immediately when the
         * refcount drops to zero, as opposed to via the vblank disable
         * timer.
         * This can be set to true it the hardware has a working vblank
         * counter and the driver uses drm_vblank_on() and drm_vblank_off()
         * appropriately.
         */
        bool vblank_disable_immediate;

        /* array of size num_crtcs */
        struct drm_vblank_crtc *vblank;

        spinlock_t vblank_time_lock;    /**< Protects vblank count and time updates during vblank enable/disable */
        spinlock_t vbl_lock;

        u32 max_vblank_count;           /**< size of vblank counter register */

        /**
         * List of events
         */
        struct list_head vblank_event_list;
        spinlock_t event_lock;

        /*@} */

        struct drm_agp_head *agp;       /**< AGP data */

        struct pci_dev *pdev;           /**< PCI device structure */
#ifdef __alpha__
        struct pci_controller *hose;
#endif

        struct platform_device *platformdev; /**< Platform device struture */
        struct virtio_device *virtdev;

        struct drm_sg_mem *sg;  /**< Scatter gather memory */
        unsigned int num_crtcs;                  /**< Number of CRTCs on this device */

        struct {
                int context;
                struct drm_hw_lock *lock;
        } sigdata;

        struct drm_local_map *agp_buffer_map;
        unsigned int agp_buffer_token;

        struct drm_mode_config mode_config;     /**< Current mode config */

        /** \name GEM information */
        /*@{ */
        struct mutex object_name_lock;
        struct idr object_name_idr;
        struct drm_vma_offset_manager *vma_offset_manager;
        /*@} */
        int switch_power_state;
};

#define DRM_SWITCH_POWER_ON 0
#define DRM_SWITCH_POWER_OFF 1
#define DRM_SWITCH_POWER_CHANGING 2
#define DRM_SWITCH_POWER_DYNAMIC_OFF 3

static __inline__ int drm_core_check_feature(struct drm_device *dev,
                                             int feature)
{
        return ((dev->driver->driver_features & feature) ? 1 : 0);
}

static inline void drm_device_set_unplugged(struct drm_device *dev)
{
        smp_wmb();
        atomic_set(&dev->unplugged, 1);
}

static inline int drm_device_is_unplugged(struct drm_device *dev)
{
        int ret = atomic_read(&dev->unplugged);
        smp_rmb();
        return ret;
}

static inline bool drm_is_render_client(const struct drm_file *file_priv)
{
        return file_priv->minor->type == DRM_MINOR_RENDER;
}

static inline bool drm_is_control_client(const struct drm_file *file_priv)
{
        return file_priv->minor->type == DRM_MINOR_CONTROL;
}

static inline bool drm_is_primary_client(const struct drm_file *file_priv)
{
        return file_priv->minor->type == DRM_MINOR_LEGACY;
}

/******************************************************************/
/** \name Internal function definitions */
/*@{*/

                                /* Driver support (drm_drv.h) */
extern int drm_ioctl_permit(u32 flags, struct drm_file *file_priv);
extern long drm_ioctl(struct file *filp,
                      unsigned int cmd, unsigned long arg);
extern long drm_compat_ioctl(struct file *filp,
                             unsigned int cmd, unsigned long arg);
extern bool drm_ioctl_flags(unsigned int nr, unsigned int *flags);

/* File Operations (drm_fops.c) */
int drm_open(struct inode *inode, struct file *filp);
ssize_t drm_read(struct file *filp, char __user *buffer,
                 size_t count, loff_t *offset);
int drm_release(struct inode *inode, struct file *filp);
int drm_new_set_master(struct drm_device *dev, struct drm_file *fpriv);
unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait);
int drm_event_reserve_init_locked(struct drm_device *dev,
                                  struct drm_file *file_priv,
                                  struct drm_pending_event *p,
                                  struct drm_event *e);
int drm_event_reserve_init(struct drm_device *dev,
                           struct drm_file *file_priv,
                           struct drm_pending_event *p,
                           struct drm_event *e);
void drm_event_cancel_free(struct drm_device *dev,
                           struct drm_pending_event *p);
void drm_send_event_locked(struct drm_device *dev, struct drm_pending_event *e);
void drm_send_event(struct drm_device *dev, struct drm_pending_event *e);

/* Misc. IOCTL support (drm_ioctl.c) */
int drm_noop(struct drm_device *dev, void *data,
             struct drm_file *file_priv);
int drm_invalid_op(struct drm_device *dev, void *data,
                   struct drm_file *file_priv);

/* Cache management (drm_cache.c) */
void drm_clflush_pages(struct page *pages[], unsigned long num_pages);
void drm_clflush_sg(struct sg_table *st);
void drm_clflush_virt_range(void *addr, unsigned long length);

/*
 * These are exported to drivers so that they can implement fencing using
 * DMA quiscent + idle. DMA quiescent usually requires the hardware lock.
 */

                                /* IRQ support (drm_irq.h) */
extern int drm_irq_install(struct drm_device *dev, int irq);
extern int drm_irq_uninstall(struct drm_device *dev);

extern int drm_vblank_init(struct drm_device *dev, unsigned int num_crtcs);
extern int drm_wait_vblank(struct drm_device *dev, void *data,
                           struct drm_file *filp);
extern u32 drm_vblank_count(struct drm_device *dev, unsigned int pipe);
extern u32 drm_crtc_vblank_count(struct drm_crtc *crtc);
extern u32 drm_vblank_count_and_time(struct drm_device *dev, unsigned int pipe,
                                     struct timeval *vblanktime);
extern u32 drm_crtc_vblank_count_and_time(struct drm_crtc *crtc,
                                          struct timeval *vblanktime);
extern void drm_send_vblank_event(struct drm_device *dev, unsigned int pipe,
                                  struct drm_pending_vblank_event *e);
extern void drm_crtc_send_vblank_event(struct drm_crtc *crtc,
                                       struct drm_pending_vblank_event *e);
extern void drm_arm_vblank_event(struct drm_device *dev, unsigned int pipe,
                                 struct drm_pending_vblank_event *e);
extern void drm_crtc_arm_vblank_event(struct drm_crtc *crtc,
                                      struct drm_pending_vblank_event *e);
extern bool drm_handle_vblank(struct drm_device *dev, unsigned int pipe);
extern bool drm_crtc_handle_vblank(struct drm_crtc *crtc);
extern int drm_vblank_get(struct drm_device *dev, unsigned int pipe);
extern void drm_vblank_put(struct drm_device *dev, unsigned int pipe);
extern int drm_crtc_vblank_get(struct drm_crtc *crtc);
extern void drm_crtc_vblank_put(struct drm_crtc *crtc);
extern void drm_wait_one_vblank(struct drm_device *dev, unsigned int pipe);
extern void drm_crtc_wait_one_vblank(struct drm_crtc *crtc);
extern void drm_vblank_off(struct drm_device *dev, unsigned int pipe);
extern void drm_vblank_on(struct drm_device *dev, unsigned int pipe);
extern void drm_crtc_vblank_off(struct drm_crtc *crtc);
extern void drm_crtc_vblank_reset(struct drm_crtc *crtc);
extern void drm_crtc_vblank_on(struct drm_crtc *crtc);
extern void drm_vblank_cleanup(struct drm_device *dev);
extern u32 drm_vblank_no_hw_counter(struct drm_device *dev, unsigned int pipe);

extern int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
                                                 unsigned int pipe, int *max_error,
                                                 struct timeval *vblank_time,
                                                 unsigned flags,

                                                 const struct drm_display_mode *mode);
extern void drm_calc_timestamping_constants(struct drm_crtc *crtc,
                                            const struct drm_display_mode *mode);

/**
 * drm_crtc_vblank_waitqueue - get vblank waitqueue for the CRTC
 * @crtc: which CRTC's vblank waitqueue to retrieve
 *
 * This function returns a pointer to the vblank waitqueue for the CRTC.
 * Drivers can use this to implement vblank waits using wait_event() & co.
 */
static inline wait_queue_head_t *drm_crtc_vblank_waitqueue(struct drm_crtc *crtc)
{
        return &crtc->dev->vblank[drm_crtc_index(crtc)].queue;
}

/* Modesetting support */
extern void drm_vblank_pre_modeset(struct drm_device *dev, unsigned int pipe);
extern void drm_vblank_post_modeset(struct drm_device *dev, unsigned int pipe);

                                /* Stub support (drm_stub.h) */
extern struct drm_master *drm_master_get(struct drm_master *master);
extern void drm_master_put(struct drm_master **master);

extern void drm_put_dev(struct drm_device *dev);
extern void drm_unplug_dev(struct drm_device *dev);
extern unsigned int drm_debug;
extern bool drm_atomic;

                                /* Debugfs support */
#if defined(CONFIG_DEBUG_FS)
extern int drm_debugfs_create_files(const struct drm_info_list *files,
                                    int count, struct dentry *root,
                                    struct drm_minor *minor);
extern int drm_debugfs_remove_files(const struct drm_info_list *files,
                                    int count, struct drm_minor *minor);
#else
static inline int drm_debugfs_create_files(const struct drm_info_list *files,
                                           int count, struct dentry *root,
                                           struct drm_minor *minor)
{
        return 0;
}

static inline int drm_debugfs_remove_files(const struct drm_info_list *files,
                                           int count, struct drm_minor *minor)
{
        return 0;
}
#endif

extern struct dma_buf *drm_gem_prime_export(struct drm_device *dev,
                struct drm_gem_object *obj, int flags);
extern int drm_gem_prime_handle_to_fd(struct drm_device *dev,
                struct drm_file *file_priv, uint32_t handle, uint32_t flags,
                int *prime_fd);
extern struct drm_gem_object *drm_gem_prime_import(struct drm_device *dev,
                struct dma_buf *dma_buf);
extern int drm_gem_prime_fd_to_handle(struct drm_device *dev,
                struct drm_file *file_priv, int prime_fd, uint32_t *handle);
extern void drm_gem_dmabuf_release(struct dma_buf *dma_buf);

extern int drm_prime_sg_to_page_addr_arrays(struct sg_table *sgt, struct page **pages,
                                            dma_addr_t *addrs, int max_pages);
extern struct sg_table *drm_prime_pages_to_sg(struct page **pages, unsigned int nr_pages);
extern void drm_prime_gem_destroy(struct drm_gem_object *obj, struct sg_table *sg);


extern struct drm_dma_handle *drm_pci_alloc(struct drm_device *dev, size_t size,
                                            size_t align);
extern void drm_pci_free(struct drm_device *dev, struct drm_dma_handle * dmah);

                               /* sysfs support (drm_sysfs.c) */
extern void drm_sysfs_hotplug_event(struct drm_device *dev);


struct drm_device *drm_dev_alloc(struct drm_driver *driver,
                                 struct device *parent);
void drm_dev_ref(struct drm_device *dev);
void drm_dev_unref(struct drm_device *dev);
int drm_dev_register(struct drm_device *dev, unsigned long flags);
void drm_dev_unregister(struct drm_device *dev);
int drm_dev_set_unique(struct drm_device *dev, const char *name);

struct drm_minor *drm_minor_acquire(unsigned int minor_id);
void drm_minor_release(struct drm_minor *minor);

/*@}*/

/* PCI section */
static __inline__ int drm_pci_device_is_agp(struct drm_device *dev)
{
        if (dev->driver->device_is_agp != NULL) {
                int err = (*dev->driver->device_is_agp) (dev);

                if (err != 2) {
                        return err;
                }
        }

        return pci_find_capability(dev->pdev, PCI_CAP_ID_AGP);
}
void drm_pci_agp_destroy(struct drm_device *dev);

extern int drm_pci_init(struct drm_driver *driver, struct pci_driver *pdriver);
extern void drm_pci_exit(struct drm_driver *driver, struct pci_driver *pdriver);
#ifdef CONFIG_PCI
extern int drm_get_pci_dev(struct pci_dev *pdev,
                           const struct pci_device_id *ent,
                           struct drm_driver *driver);
extern int drm_pci_set_busid(struct drm_device *dev, struct drm_master *master);
#else
static inline int drm_get_pci_dev(struct pci_dev *pdev,
                                  const struct pci_device_id *ent,
                                  struct drm_driver *driver)
{
        return -ENOSYS;
}

static inline int drm_pci_set_busid(struct drm_device *dev,
                                    struct drm_master *master)
{
        return -ENOSYS;
}
#endif

#define DRM_PCIE_SPEED_25 1
#define DRM_PCIE_SPEED_50 2
#define DRM_PCIE_SPEED_80 4

extern int drm_pcie_get_speed_cap_mask(struct drm_device *dev, u32 *speed_mask);
extern int drm_pcie_get_max_link_width(struct drm_device *dev, u32 *mlw);

/* platform section */
extern int drm_platform_init(struct drm_driver *driver, struct platform_device *platform_device);
extern int drm_platform_set_busid(struct drm_device *d, struct drm_master *m);

/* returns true if currently okay to sleep */
static __inline__ bool drm_can_sleep(void)
{
        if (in_atomic() || in_dbg_master() || irqs_disabled())
                return false;
        return true;
}

/* helper for handling conditionals in various for_each macros */
#define for_each_if(condition) if (!(condition)) {} else

#endif