/**************************************************************************
 *
 * Copyright © 2009-2015 VMware, Inc., Palo Alto, CA., USA
 * 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, sub license, 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 NON-INFRINGEMENT. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDERS, AUTHORS 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 "vmwgfx_drv.h"
#include "vmwgfx_resource_priv.h"
#include "vmwgfx_binding.h"
#include "ttm/ttm_placement.h"

struct vmw_user_context {
        struct ttm_base_object base;
        struct vmw_resource res;
        struct vmw_ctx_binding_state *cbs;
        struct vmw_cmdbuf_res_manager *man;
        struct vmw_resource *cotables[SVGA_COTABLE_DX10_MAX];
        spinlock_t cotable_lock;
        struct vmw_dma_buffer *dx_query_mob;
};

static void vmw_user_context_free(struct vmw_resource *res);
static struct vmw_resource *
vmw_user_context_base_to_res(struct ttm_base_object *base);

static int vmw_gb_context_create(struct vmw_resource *res);
static int vmw_gb_context_bind(struct vmw_resource *res,
                               struct ttm_validate_buffer *val_buf);
static int vmw_gb_context_unbind(struct vmw_resource *res,
                                 bool readback,
                                 struct ttm_validate_buffer *val_buf);
static int vmw_gb_context_destroy(struct vmw_resource *res);
static int vmw_dx_context_create(struct vmw_resource *res);
static int vmw_dx_context_bind(struct vmw_resource *res,
                               struct ttm_validate_buffer *val_buf);
static int vmw_dx_context_unbind(struct vmw_resource *res,
                                 bool readback,
                                 struct ttm_validate_buffer *val_buf);
static int vmw_dx_context_destroy(struct vmw_resource *res);

static uint64_t vmw_user_context_size;

static const struct vmw_user_resource_conv user_context_conv = {
        .object_type = VMW_RES_CONTEXT,
        .base_obj_to_res = vmw_user_context_base_to_res,
        .res_free = vmw_user_context_free
};

const struct vmw_user_resource_conv *user_context_converter =
        &user_context_conv;


static const struct vmw_res_func vmw_legacy_context_func = {
        .res_type = vmw_res_context,
        .needs_backup = false,
        .may_evict = false,
        .type_name = "legacy contexts",
        .backup_placement = NULL,
        .create = NULL,
        .destroy = NULL,
        .bind = NULL,
        .unbind = NULL
};

static const struct vmw_res_func vmw_gb_context_func = {
        .res_type = vmw_res_context,
        .needs_backup = true,
        .may_evict = true,
        .type_name = "guest backed contexts",
        .backup_placement = &vmw_mob_placement,
        .create = vmw_gb_context_create,
        .destroy = vmw_gb_context_destroy,
        .bind = vmw_gb_context_bind,
        .unbind = vmw_gb_context_unbind
};

static const struct vmw_res_func vmw_dx_context_func = {
        .res_type = vmw_res_dx_context,
        .needs_backup = true,
        .may_evict = true,
        .type_name = "dx contexts",
        .backup_placement = &vmw_mob_placement,
        .create = vmw_dx_context_create,
        .destroy = vmw_dx_context_destroy,
        .bind = vmw_dx_context_bind,
        .unbind = vmw_dx_context_unbind
};

/**
 * Context management:
 */

static void vmw_context_cotables_unref(struct vmw_user_context *uctx)
{
        struct vmw_resource *res;
        int i;

        for (i = 0; i < SVGA_COTABLE_DX10_MAX; ++i) {
                spin_lock(&uctx->cotable_lock);
                res = uctx->cotables[i];
                uctx->cotables[i] = NULL;
                spin_unlock(&uctx->cotable_lock);

                if (res)
                        vmw_resource_unreference(&res);
        }
}

static void vmw_hw_context_destroy(struct vmw_resource *res)
{
        struct vmw_user_context *uctx =
                container_of(res, struct vmw_user_context, res);
        struct vmw_private *dev_priv = res->dev_priv;
        struct {
                SVGA3dCmdHeader header;
                SVGA3dCmdDestroyContext body;
        } *cmd;


        if (res->func->destroy == vmw_gb_context_destroy ||
            res->func->destroy == vmw_dx_context_destroy) {
                mutex_lock(&dev_priv->cmdbuf_mutex);
                vmw_cmdbuf_res_man_destroy(uctx->man);
                mutex_lock(&dev_priv->binding_mutex);
                vmw_binding_state_kill(uctx->cbs);
                (void) res->func->destroy(res);
                mutex_unlock(&dev_priv->binding_mutex);
                if (dev_priv->pinned_bo != NULL &&
                    !dev_priv->query_cid_valid)
                        __vmw_execbuf_release_pinned_bo(dev_priv, NULL);
                mutex_unlock(&dev_priv->cmdbuf_mutex);
                vmw_context_cotables_unref(uctx);
                return;
        }

        vmw_execbuf_release_pinned_bo(dev_priv);
        cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
        if (unlikely(cmd == NULL)) {
                DRM_ERROR("Failed reserving FIFO space for surface "
                          "destruction.\n");
                return;
        }

        cmd->header.id = SVGA_3D_CMD_CONTEXT_DESTROY;
        cmd->header.size = sizeof(cmd->body);
        cmd->body.cid = res->id;

        vmw_fifo_commit(dev_priv, sizeof(*cmd));
        vmw_fifo_resource_dec(dev_priv);
}

static int vmw_gb_context_init(struct vmw_private *dev_priv,
                               bool dx,
                               struct vmw_resource *res,
                               void (*res_free)(struct vmw_resource *res))
{
        int ret, i;
        struct vmw_user_context *uctx =
                container_of(res, struct vmw_user_context, res);

        res->backup_size = (dx ? sizeof(SVGADXContextMobFormat) :
                            SVGA3D_CONTEXT_DATA_SIZE);
        ret = vmw_resource_init(dev_priv, res, true,
                                res_free,
                                dx ? &vmw_dx_context_func :
                                &vmw_gb_context_func);
        if (unlikely(ret != 0))
                goto out_err;

        if (dev_priv->has_mob) {
                uctx->man = vmw_cmdbuf_res_man_create(dev_priv);
                if (IS_ERR(uctx->man)) {
                        ret = PTR_ERR(uctx->man);
                        uctx->man = NULL;
                        goto out_err;
                }
        }

        uctx->cbs = vmw_binding_state_alloc(dev_priv);
        if (IS_ERR(uctx->cbs)) {
                ret = PTR_ERR(uctx->cbs);
                goto out_err;
        }

        spin_lock_init(&uctx->cotable_lock);

        if (dx) {
                for (i = 0; i < SVGA_COTABLE_DX10_MAX; ++i) {
                        uctx->cotables[i] = vmw_cotable_alloc(dev_priv,
                                                              &uctx->res, i);
                        if (unlikely(uctx->cotables[i] == NULL)) {
                                ret = -ENOMEM;
                                goto out_cotables;
                        }
                }
        }



        vmw_resource_activate(res, vmw_hw_context_destroy);
        return 0;

out_cotables:
        vmw_context_cotables_unref(uctx);
out_err:
        if (res_free)
                res_free(res);
        else
                kfree(res);
        return ret;
}

static int vmw_context_init(struct vmw_private *dev_priv,
                            struct vmw_resource *res,
                            void (*res_free)(struct vmw_resource *res),
                            bool dx)
{
        int ret;

        struct {
                SVGA3dCmdHeader header;
                SVGA3dCmdDefineContext body;
        } *cmd;

        if (dev_priv->has_mob)
                return vmw_gb_context_init(dev_priv, dx, res, res_free);

        ret = vmw_resource_init(dev_priv, res, false,
                                res_free, &vmw_legacy_context_func);

        if (unlikely(ret != 0)) {
                DRM_ERROR("Failed to allocate a resource id.\n");
                goto out_early;
        }

        if (unlikely(res->id >= SVGA3D_MAX_CONTEXT_IDS)) {
                DRM_ERROR("Out of hw context ids.\n");
                vmw_resource_unreference(&res);
                return -ENOMEM;
        }

        cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
        if (unlikely(cmd == NULL)) {
                DRM_ERROR("Fifo reserve failed.\n");
                vmw_resource_unreference(&res);
                return -ENOMEM;
        }

        cmd->header.id = SVGA_3D_CMD_CONTEXT_DEFINE;
        cmd->header.size = sizeof(cmd->body);
        cmd->body.cid = res->id;

        vmw_fifo_commit(dev_priv, sizeof(*cmd));
        vmw_fifo_resource_inc(dev_priv);
        vmw_resource_activate(res, vmw_hw_context_destroy);
        return 0;

out_early:
        if (res_free == NULL)
                kfree(res);
        else
                res_free(res);
        return ret;
}


/*
 * GB context.
 */

static int vmw_gb_context_create(struct vmw_resource *res)
{
        struct vmw_private *dev_priv = res->dev_priv;
        int ret;
        struct {
                SVGA3dCmdHeader header;
                SVGA3dCmdDefineGBContext body;
        } *cmd;

        if (likely(res->id != -1))
                return 0;

        ret = vmw_resource_alloc_id(res);
        if (unlikely(ret != 0)) {
                DRM_ERROR("Failed to allocate a context id.\n");
                goto out_no_id;
        }

        if (unlikely(res->id >= VMWGFX_NUM_GB_CONTEXT)) {
                ret = -EBUSY;
                goto out_no_fifo;
        }

        cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
        if (unlikely(cmd == NULL)) {
                DRM_ERROR("Failed reserving FIFO space for context "
                          "creation.\n");
                ret = -ENOMEM;
                goto out_no_fifo;
        }

        cmd->header.id = SVGA_3D_CMD_DEFINE_GB_CONTEXT;
        cmd->header.size = sizeof(cmd->body);
        cmd->body.cid = res->id;
        vmw_fifo_commit(dev_priv, sizeof(*cmd));
        vmw_fifo_resource_inc(dev_priv);

        return 0;

out_no_fifo:
        vmw_resource_release_id(res);
out_no_id:
        return ret;
}

static int vmw_gb_context_bind(struct vmw_resource *res,
                               struct ttm_validate_buffer *val_buf)
{
        struct vmw_private *dev_priv = res->dev_priv;
        struct {
                SVGA3dCmdHeader header;
                SVGA3dCmdBindGBContext body;
        } *cmd;
        struct ttm_buffer_object *bo = val_buf->bo;

        BUG_ON(bo->mem.mem_type != VMW_PL_MOB);

        cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
        if (unlikely(cmd == NULL)) {
                DRM_ERROR("Failed reserving FIFO space for context "
                          "binding.\n");
                return -ENOMEM;
        }
        cmd->header.id = SVGA_3D_CMD_BIND_GB_CONTEXT;
        cmd->header.size = sizeof(cmd->body);
        cmd->body.cid = res->id;
        cmd->body.mobid = bo->mem.start;
        cmd->body.validContents = res->backup_dirty;
        res->backup_dirty = false;
        vmw_fifo_commit(dev_priv, sizeof(*cmd));

        return 0;
}

static int vmw_gb_context_unbind(struct vmw_resource *res,
                                 bool readback,
                                 struct ttm_validate_buffer *val_buf)
{
        struct vmw_private *dev_priv = res->dev_priv;
        struct ttm_buffer_object *bo = val_buf->bo;
        struct vmw_fence_obj *fence;
        struct vmw_user_context *uctx =
                container_of(res, struct vmw_user_context, res);

        struct {
                SVGA3dCmdHeader header;
                SVGA3dCmdReadbackGBContext body;
        } *cmd1;
        struct {
                SVGA3dCmdHeader header;
                SVGA3dCmdBindGBContext body;
        } *cmd2;
        uint32_t submit_size;
        uint8_t *cmd;


        BUG_ON(bo->mem.mem_type != VMW_PL_MOB);

        mutex_lock(&dev_priv->binding_mutex);
        vmw_binding_state_scrub(uctx->cbs);

        submit_size = sizeof(*cmd2) + (readback ? sizeof(*cmd1) : 0);

        cmd = vmw_fifo_reserve(dev_priv, submit_size);
        if (unlikely(cmd == NULL)) {
                DRM_ERROR("Failed reserving FIFO space for context "
                          "unbinding.\n");
                mutex_unlock(&dev_priv->binding_mutex);
                return -ENOMEM;
        }

        cmd2 = (void *) cmd;
        if (readback) {
                cmd1 = (void *) cmd;
                cmd1->header.id = SVGA_3D_CMD_READBACK_GB_CONTEXT;
                cmd1->header.size = sizeof(cmd1->body);
                cmd1->body.cid = res->id;
                cmd2 = (void *) (&cmd1[1]);
        }
        cmd2->header.id = SVGA_3D_CMD_BIND_GB_CONTEXT;
        cmd2->header.size = sizeof(cmd2->body);
        cmd2->body.cid = res->id;
        cmd2->body.mobid = SVGA3D_INVALID_ID;

        vmw_fifo_commit(dev_priv, submit_size);
        mutex_unlock(&dev_priv->binding_mutex);

        /*
         * Create a fence object and fence the backup buffer.
         */

        (void) vmw_execbuf_fence_commands(NULL, dev_priv,
                                          &fence, NULL);

        vmw_fence_single_bo(bo, fence);

        if (likely(fence != NULL))
                vmw_fence_obj_unreference(&fence);

        return 0;
}

static int vmw_gb_context_destroy(struct vmw_resource *res)
{
        struct vmw_private *dev_priv = res->dev_priv;
        struct {
                SVGA3dCmdHeader header;
                SVGA3dCmdDestroyGBContext body;
        } *cmd;

        if (likely(res->id == -1))
                return 0;

        cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
        if (unlikely(cmd == NULL)) {
                DRM_ERROR("Failed reserving FIFO space for context "
                          "destruction.\n");
                return -ENOMEM;
        }

        cmd->header.id = SVGA_3D_CMD_DESTROY_GB_CONTEXT;
        cmd->header.size = sizeof(cmd->body);
        cmd->body.cid = res->id;
        vmw_fifo_commit(dev_priv, sizeof(*cmd));
        if (dev_priv->query_cid == res->id)
                dev_priv->query_cid_valid = false;
        vmw_resource_release_id(res);
        vmw_fifo_resource_dec(dev_priv);

        return 0;
}

/*
 * DX context.
 */

static int vmw_dx_context_create(struct vmw_resource *res)
{
        struct vmw_private *dev_priv = res->dev_priv;
        int ret;
        struct {
                SVGA3dCmdHeader header;
                SVGA3dCmdDXDefineContext body;
        } *cmd;

        if (likely(res->id != -1))
                return 0;

        ret = vmw_resource_alloc_id(res);
        if (unlikely(ret != 0)) {
                DRM_ERROR("Failed to allocate a context id.\n");
                goto out_no_id;
        }

        if (unlikely(res->id >= VMWGFX_NUM_DXCONTEXT)) {
                ret = -EBUSY;
                goto out_no_fifo;
        }

        cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
        if (unlikely(cmd == NULL)) {
                DRM_ERROR("Failed reserving FIFO space for context "
                          "creation.\n");
                ret = -ENOMEM;
                goto out_no_fifo;
        }

        cmd->header.id = SVGA_3D_CMD_DX_DEFINE_CONTEXT;
        cmd->header.size = sizeof(cmd->body);
        cmd->body.cid = res->id;
        vmw_fifo_commit(dev_priv, sizeof(*cmd));
        vmw_fifo_resource_inc(dev_priv);

        return 0;

out_no_fifo:
        vmw_resource_release_id(res);
out_no_id:
        return ret;
}

static int vmw_dx_context_bind(struct vmw_resource *res,
                               struct ttm_validate_buffer *val_buf)
{
        struct vmw_private *dev_priv = res->dev_priv;
        struct {
                SVGA3dCmdHeader header;
                SVGA3dCmdDXBindContext body;
        } *cmd;
        struct ttm_buffer_object *bo = val_buf->bo;

        BUG_ON(bo->mem.mem_type != VMW_PL_MOB);

        cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
        if (unlikely(cmd == NULL)) {
                DRM_ERROR("Failed reserving FIFO space for context "
                          "binding.\n");
                return -ENOMEM;
        }

        cmd->header.id = SVGA_3D_CMD_DX_BIND_CONTEXT;
        cmd->header.size = sizeof(cmd->body);
        cmd->body.cid = res->id;
        cmd->body.mobid = bo->mem.start;
        cmd->body.validContents = res->backup_dirty;
        res->backup_dirty = false;
        vmw_fifo_commit(dev_priv, sizeof(*cmd));


        return 0;
}

/**
 * vmw_dx_context_scrub_cotables - Scrub all bindings and
 * cotables from a context
 *
 * @ctx: Pointer to the context resource
 * @readback: Whether to save the otable contents on scrubbing.
 *
 * COtables must be unbound before their context, but unbinding requires
 * the backup buffer being reserved, whereas scrubbing does not.
 * This function scrubs all cotables of a context, potentially reading back
 * the contents into their backup buffers. However, scrubbing cotables
 * also makes the device context invalid, so scrub all bindings first so
 * that doesn't have to be done later with an invalid context.
 */
void vmw_dx_context_scrub_cotables(struct vmw_resource *ctx,
                                   bool readback)
{
        struct vmw_user_context *uctx =
                container_of(ctx, struct vmw_user_context, res);
        int i;

        vmw_binding_state_scrub(uctx->cbs);
        for (i = 0; i < SVGA_COTABLE_DX10_MAX; ++i) {
                struct vmw_resource *res;

                /* Avoid racing with ongoing cotable destruction. */
                spin_lock(&uctx->cotable_lock);
                res = uctx->cotables[vmw_cotable_scrub_order[i]];
                if (res)
                        res = vmw_resource_reference_unless_doomed(res);
                spin_unlock(&uctx->cotable_lock);
                if (!res)
                        continue;

                WARN_ON(vmw_cotable_scrub(res, readback));
                vmw_resource_unreference(&res);
        }
}

static int vmw_dx_context_unbind(struct vmw_resource *res,
                                 bool readback,
                                 struct ttm_validate_buffer *val_buf)
{
        struct vmw_private *dev_priv = res->dev_priv;
        struct ttm_buffer_object *bo = val_buf->bo;
        struct vmw_fence_obj *fence;
        struct vmw_user_context *uctx =
                container_of(res, struct vmw_user_context, res);

        struct {
                SVGA3dCmdHeader header;
                SVGA3dCmdDXReadbackContext body;
        } *cmd1;
        struct {
                SVGA3dCmdHeader header;
                SVGA3dCmdDXBindContext body;
        } *cmd2;
        uint32_t submit_size;
        uint8_t *cmd;


        BUG_ON(bo->mem.mem_type != VMW_PL_MOB);

        mutex_lock(&dev_priv->binding_mutex);
        vmw_dx_context_scrub_cotables(res, readback);

        if (uctx->dx_query_mob && uctx->dx_query_mob->dx_query_ctx &&
            readback) {
                WARN_ON(uctx->dx_query_mob->dx_query_ctx != res);
                if (vmw_query_readback_all(uctx->dx_query_mob))
                        DRM_ERROR("Failed to read back query states\n");
        }

        submit_size = sizeof(*cmd2) + (readback ? sizeof(*cmd1) : 0);

        cmd = vmw_fifo_reserve(dev_priv, submit_size);
        if (unlikely(cmd == NULL)) {
                DRM_ERROR("Failed reserving FIFO space for context "
                          "unbinding.\n");
                mutex_unlock(&dev_priv->binding_mutex);
                return -ENOMEM;
        }

        cmd2 = (void *) cmd;
        if (readback) {
                cmd1 = (void *) cmd;
                cmd1->header.id = SVGA_3D_CMD_DX_READBACK_CONTEXT;
                cmd1->header.size = sizeof(cmd1->body);
                cmd1->body.cid = res->id;
                cmd2 = (void *) (&cmd1[1]);
        }
        cmd2->header.id = SVGA_3D_CMD_DX_BIND_CONTEXT;
        cmd2->header.size = sizeof(cmd2->body);
        cmd2->body.cid = res->id;
        cmd2->body.mobid = SVGA3D_INVALID_ID;

        vmw_fifo_commit(dev_priv, submit_size);
        mutex_unlock(&dev_priv->binding_mutex);

        /*
         * Create a fence object and fence the backup buffer.
         */

        (void) vmw_execbuf_fence_commands(NULL, dev_priv,
                                          &fence, NULL);

        vmw_fence_single_bo(bo, fence);

        if (likely(fence != NULL))
                vmw_fence_obj_unreference(&fence);

        return 0;
}

static int vmw_dx_context_destroy(struct vmw_resource *res)
{
        struct vmw_private *dev_priv = res->dev_priv;
        struct {
                SVGA3dCmdHeader header;
                SVGA3dCmdDXDestroyContext body;
        } *cmd;

        if (likely(res->id == -1))
                return 0;

        cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
        if (unlikely(cmd == NULL)) {
                DRM_ERROR("Failed reserving FIFO space for context "
                          "destruction.\n");
                return -ENOMEM;
        }

        cmd->header.id = SVGA_3D_CMD_DX_DESTROY_CONTEXT;
        cmd->header.size = sizeof(cmd->body);
        cmd->body.cid = res->id;
        vmw_fifo_commit(dev_priv, sizeof(*cmd));
        if (dev_priv->query_cid == res->id)
                dev_priv->query_cid_valid = false;
        vmw_resource_release_id(res);
        vmw_fifo_resource_dec(dev_priv);

        return 0;
}

/**
 * User-space context management:
 */

static struct vmw_resource *
vmw_user_context_base_to_res(struct ttm_base_object *base)
{
        return &(container_of(base, struct vmw_user_context, base)->res);
}

static void vmw_user_context_free(struct vmw_resource *res)
{
        struct vmw_user_context *ctx =
            container_of(res, struct vmw_user_context, res);
        struct vmw_private *dev_priv = res->dev_priv;

        if (ctx->cbs)
                vmw_binding_state_free(ctx->cbs);

        (void) vmw_context_bind_dx_query(res, NULL);

        ttm_base_object_kfree(ctx, base);
        ttm_mem_global_free(vmw_mem_glob(dev_priv),
                            vmw_user_context_size);
}

/**
 * This function is called when user space has no more references on the
 * base object. It releases the base-object's reference on the resource object.
 */

static void vmw_user_context_base_release(struct ttm_base_object **p_base)
{
        struct ttm_base_object *base = *p_base;
        struct vmw_user_context *ctx =
            container_of(base, struct vmw_user_context, base);
        struct vmw_resource *res = &ctx->res;

        *p_base = NULL;
        vmw_resource_unreference(&res);
}

int vmw_context_destroy_ioctl(struct drm_device *dev, void *data,
                              struct drm_file *file_priv)
{
        struct drm_vmw_context_arg *arg = (struct drm_vmw_context_arg *)data;
        struct ttm_object_file *tfile = vmw_fpriv(file_priv)->tfile;

        return ttm_ref_object_base_unref(tfile, arg->cid, TTM_REF_USAGE);
}

static int vmw_context_define(struct drm_device *dev, void *data,
                              struct drm_file *file_priv, bool dx)
{
        struct vmw_private *dev_priv = vmw_priv(dev);
        struct vmw_user_context *ctx;
        struct vmw_resource *res;
        struct vmw_resource *tmp;
        struct drm_vmw_context_arg *arg = (struct drm_vmw_context_arg *)data;
        struct ttm_object_file *tfile = vmw_fpriv(file_priv)->tfile;
        int ret;

        if (!dev_priv->has_dx && dx) {
                DRM_ERROR("DX contexts not supported by device.\n");
                return -EINVAL;
        }

        /*
         * Approximate idr memory usage with 128 bytes. It will be limited
         * by maximum number_of contexts anyway.
         */

        if (unlikely(vmw_user_context_size == 0))
                vmw_user_context_size = ttm_round_pot(sizeof(*ctx)) + 128 +
                  ((dev_priv->has_mob) ? vmw_cmdbuf_res_man_size() : 0);

        ret = ttm_read_lock(&dev_priv->reservation_sem, true);
        if (unlikely(ret != 0))
                return ret;

        ret = ttm_mem_global_alloc(vmw_mem_glob(dev_priv),
                                   vmw_user_context_size,
                                   false, true);
        if (unlikely(ret != 0)) {
                if (ret != -ERESTARTSYS)
                        DRM_ERROR("Out of graphics memory for context"
                                  " creation.\n");
                goto out_unlock;
        }

        ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
        if (unlikely(ctx == NULL)) {
                ttm_mem_global_free(vmw_mem_glob(dev_priv),
                                    vmw_user_context_size);
                ret = -ENOMEM;
                goto out_unlock;
        }

        res = &ctx->res;
        ctx->base.shareable = false;
        ctx->base.tfile = NULL;

        /*
         * From here on, the destructor takes over resource freeing.
         */

        ret = vmw_context_init(dev_priv, res, vmw_user_context_free, dx);
        if (unlikely(ret != 0))
                goto out_unlock;

        tmp = vmw_resource_reference(&ctx->res);
        ret = ttm_base_object_init(tfile, &ctx->base, false, VMW_RES_CONTEXT,
                                   &vmw_user_context_base_release, NULL);

        if (unlikely(ret != 0)) {
                vmw_resource_unreference(&tmp);
                goto out_err;
        }

        arg->cid = ctx->base.hash.key;
out_err:
        vmw_resource_unreference(&res);
out_unlock:
        ttm_read_unlock(&dev_priv->reservation_sem);
        return ret;
}

int vmw_context_define_ioctl(struct drm_device *dev, void *data,
                             struct drm_file *file_priv)
{
        return vmw_context_define(dev, data, file_priv, false);
}

int vmw_extended_context_define_ioctl(struct drm_device *dev, void *data,
                                      struct drm_file *file_priv)
{
        union drm_vmw_extended_context_arg *arg = (typeof(arg)) data;
        struct drm_vmw_context_arg *rep = &arg->rep;

        switch (arg->req) {
        case drm_vmw_context_legacy:
                return vmw_context_define(dev, rep, file_priv, false);
        case drm_vmw_context_dx:
                return vmw_context_define(dev, rep, file_priv, true);
        default:
                break;
        }
        return -EINVAL;
}

/**
 * vmw_context_binding_list - Return a list of context bindings
 *
 * @ctx: The context resource
 *
 * Returns the current list of bindings of the given context. Note that
 * this list becomes stale as soon as the dev_priv::binding_mutex is unlocked.
 */
struct list_head *vmw_context_binding_list(struct vmw_resource *ctx)
{
        struct vmw_user_context *uctx =
                container_of(ctx, struct vmw_user_context, res);

        return vmw_binding_state_list(uctx->cbs);
}

struct vmw_cmdbuf_res_manager *vmw_context_res_man(struct vmw_resource *ctx)
{
        return container_of(ctx, struct vmw_user_context, res)->man;
}

struct vmw_resource *vmw_context_cotable(struct vmw_resource *ctx,
                                         SVGACOTableType cotable_type)
{
        if (cotable_type >= SVGA_COTABLE_DX10_MAX)
                return ERR_PTR(-EINVAL);

        return vmw_resource_reference
                (container_of(ctx, struct vmw_user_context, res)->
                 cotables[cotable_type]);
}

/**
 * vmw_context_binding_state -
 * Return a pointer to a context binding state structure
 *
 * @ctx: The context resource
 *
 * Returns the current state of bindings of the given context. Note that
 * this state becomes stale as soon as the dev_priv::binding_mutex is unlocked.
 */
struct vmw_ctx_binding_state *
vmw_context_binding_state(struct vmw_resource *ctx)
{
        return container_of(ctx, struct vmw_user_context, res)->cbs;
}

/**
 * vmw_context_bind_dx_query -
 * Sets query MOB for the context.  If @mob is NULL, then this function will
 * remove the association between the MOB and the context.  This function
 * assumes the binding_mutex is held.
 *
 * @ctx_res: The context resource
 * @mob: a reference to the query MOB
 *
 * Returns -EINVAL if a MOB has already been set and does not match the one
 * specified in the parameter.  0 otherwise.
 */
int vmw_context_bind_dx_query(struct vmw_resource *ctx_res,
                              struct vmw_dma_buffer *mob)
{
        struct vmw_user_context *uctx =
                container_of(ctx_res, struct vmw_user_context, res);

        if (mob == NULL) {
                if (uctx->dx_query_mob) {
                        uctx->dx_query_mob->dx_query_ctx = NULL;
                        vmw_dmabuf_unreference(&uctx->dx_query_mob);
                        uctx->dx_query_mob = NULL;
                }

                return 0;
        }

        /* Can only have one MOB per context for queries */
        if (uctx->dx_query_mob && uctx->dx_query_mob != mob)
                return -EINVAL;

        mob->dx_query_ctx  = ctx_res;

        if (!uctx->dx_query_mob)
                uctx->dx_query_mob = vmw_dmabuf_reference(mob);

        return 0;
}

/**
 * vmw_context_get_dx_query_mob - Returns non-counted reference to DX query mob
 *
 * @ctx_res: The context resource
 */
struct vmw_dma_buffer *
vmw_context_get_dx_query_mob(struct vmw_resource *ctx_res)
{
        struct vmw_user_context *uctx =
                container_of(ctx_res, struct vmw_user_context, res);

        return uctx->dx_query_mob;
}