/**************************************************************************
 *
 * Copyright © 2009-2012 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 "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;
};



typedef int (*vmw_scrub_func)(struct vmw_ctx_bindinfo *, bool);

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_context_scrub_shader(struct vmw_ctx_bindinfo *bi, bool rebind);
static int vmw_context_scrub_render_target(struct vmw_ctx_bindinfo *bi,
                                           bool rebind);
static int vmw_context_scrub_texture(struct vmw_ctx_bindinfo *bi, bool rebind);
static void vmw_context_binding_state_scrub(struct vmw_ctx_binding_state *cbs);
static void vmw_context_binding_state_kill(struct vmw_ctx_binding_state *cbs);
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 vmw_scrub_func vmw_scrub_funcs[vmw_ctx_binding_max] = {
        [vmw_ctx_binding_shader] = vmw_context_scrub_shader,
        [vmw_ctx_binding_rt] = vmw_context_scrub_render_target,
        [vmw_ctx_binding_tex] = vmw_context_scrub_texture };

/**
 * Context management:
 */

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) {
                mutex_lock(&dev_priv->cmdbuf_mutex);
                vmw_cmdbuf_res_man_destroy(uctx->man);
                mutex_lock(&dev_priv->binding_mutex);
                (void) vmw_context_binding_state_kill(&uctx->cbs);
                (void) vmw_gb_context_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);
                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 = cpu_to_le32(SVGA_3D_CMD_CONTEXT_DESTROY);
        cmd->header.size = cpu_to_le32(sizeof(cmd->body));
        cmd->body.cid = cpu_to_le32(res->id);

        vmw_fifo_commit(dev_priv, sizeof(*cmd));
        vmw_3d_resource_dec(dev_priv, false);
}

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

        ret = vmw_resource_init(dev_priv, res, true,
                                res_free, &vmw_gb_context_func);
        res->backup_size = SVGA3D_CONTEXT_DATA_SIZE;
        if (unlikely(ret != 0))
                goto out_err;

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

        memset(&uctx->cbs, 0, sizeof(uctx->cbs));
        INIT_LIST_HEAD(&uctx->cbs.list);

        vmw_resource_activate(res, vmw_hw_context_destroy);
        return 0;

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))
{
        int ret;

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

        if (dev_priv->has_mob)
                return vmw_gb_context_init(dev_priv, 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 = cpu_to_le32(SVGA_3D_CMD_CONTEXT_DEFINE);
        cmd->header.size = cpu_to_le32(sizeof(cmd->body));
        cmd->body.cid = cpu_to_le32(res->id);

        vmw_fifo_commit(dev_priv, sizeof(*cmd));
        (void) vmw_3d_resource_inc(dev_priv, false);
        vmw_resource_activate(res, vmw_hw_context_destroy);
        return 0;

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

struct vmw_resource *vmw_context_alloc(struct vmw_private *dev_priv)
{
        struct vmw_resource *res = kmalloc(sizeof(*res), GFP_KERNEL);
        int ret;

        if (unlikely(res == NULL))
                return NULL;

        ret = vmw_context_init(dev_priv, res, NULL);

        return (ret == 0) ? res : NULL;
}


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));
        (void) vmw_3d_resource_inc(dev_priv, false);

        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_context_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_3d_resource_dec(dev_priv, false);

        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;

        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);
}

int vmw_context_define_ioctl(struct drm_device *dev, void *data,
                             struct drm_file *file_priv)
{
        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;


        /*
         * 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);
        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;

}

/**
 * vmw_context_scrub_shader - scrub a shader binding from a context.
 *
 * @bi: single binding information.
 * @rebind: Whether to issue a bind instead of scrub command.
 */
static int vmw_context_scrub_shader(struct vmw_ctx_bindinfo *bi, bool rebind)
{
        struct vmw_private *dev_priv = bi->ctx->dev_priv;
        struct {
                SVGA3dCmdHeader header;
                SVGA3dCmdSetShader body;
        } *cmd;

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

        cmd->header.id = SVGA_3D_CMD_SET_SHADER;
        cmd->header.size = sizeof(cmd->body);
        cmd->body.cid = bi->ctx->id;
        cmd->body.type = bi->i1.shader_type;
        cmd->body.shid = ((rebind) ? bi->res->id : SVGA3D_INVALID_ID);
        vmw_fifo_commit(dev_priv, sizeof(*cmd));

        return 0;
}

/**
 * vmw_context_scrub_render_target - scrub a render target binding
 * from a context.
 *
 * @bi: single binding information.
 * @rebind: Whether to issue a bind instead of scrub command.
 */
static int vmw_context_scrub_render_target(struct vmw_ctx_bindinfo *bi,
                                           bool rebind)
{
        struct vmw_private *dev_priv = bi->ctx->dev_priv;
        struct {
                SVGA3dCmdHeader header;
                SVGA3dCmdSetRenderTarget body;
        } *cmd;

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

        cmd->header.id = SVGA_3D_CMD_SETRENDERTARGET;
        cmd->header.size = sizeof(cmd->body);
        cmd->body.cid = bi->ctx->id;
        cmd->body.type = bi->i1.rt_type;
        cmd->body.target.sid = ((rebind) ? bi->res->id : SVGA3D_INVALID_ID);
        cmd->body.target.face = 0;
        cmd->body.target.mipmap = 0;
        vmw_fifo_commit(dev_priv, sizeof(*cmd));

        return 0;
}

/**
 * vmw_context_scrub_texture - scrub a texture binding from a context.
 *
 * @bi: single binding information.
 * @rebind: Whether to issue a bind instead of scrub command.
 *
 * TODO: Possibly complement this function with a function that takes
 * a list of texture bindings and combines them to a single command.
 */
static int vmw_context_scrub_texture(struct vmw_ctx_bindinfo *bi,
                                     bool rebind)
{
        struct vmw_private *dev_priv = bi->ctx->dev_priv;
        struct {
                SVGA3dCmdHeader header;
                struct {
                        SVGA3dCmdSetTextureState c;
                        SVGA3dTextureState s1;
                } body;
        } *cmd;

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


        cmd->header.id = SVGA_3D_CMD_SETTEXTURESTATE;
        cmd->header.size = sizeof(cmd->body);
        cmd->body.c.cid = bi->ctx->id;
        cmd->body.s1.stage = bi->i1.texture_stage;
        cmd->body.s1.name = SVGA3D_TS_BIND_TEXTURE;
        cmd->body.s1.value = ((rebind) ? bi->res->id : SVGA3D_INVALID_ID);
        vmw_fifo_commit(dev_priv, sizeof(*cmd));

        return 0;
}

/**
 * vmw_context_binding_drop: Stop tracking a context binding
 *
 * @cb: Pointer to binding tracker storage.
 *
 * Stops tracking a context binding, and re-initializes its storage.
 * Typically used when the context binding is replaced with a binding to
 * another (or the same, for that matter) resource.
 */
static void vmw_context_binding_drop(struct vmw_ctx_binding *cb)
{
        list_del(&cb->ctx_list);
        if (!list_empty(&cb->res_list))
                list_del(&cb->res_list);
        cb->bi.ctx = NULL;
}

/**
 * vmw_context_binding_add: Start tracking a context binding
 *
 * @cbs: Pointer to the context binding state tracker.
 * @bi: Information about the binding to track.
 *
 * Performs basic checks on the binding to make sure arguments are within
 * bounds and then starts tracking the binding in the context binding
 * state structure @cbs.
 */
int vmw_context_binding_add(struct vmw_ctx_binding_state *cbs,
                            const struct vmw_ctx_bindinfo *bi)
{
        struct vmw_ctx_binding *loc;

        switch (bi->bt) {
        case vmw_ctx_binding_rt:
                if (unlikely((unsigned)bi->i1.rt_type >= SVGA3D_RT_MAX)) {
                        DRM_ERROR("Illegal render target type %u.\n",
                                  (unsigned) bi->i1.rt_type);
                        return -EINVAL;
                }
                loc = &cbs->render_targets[bi->i1.rt_type];
                break;
        case vmw_ctx_binding_tex:
                if (unlikely((unsigned)bi->i1.texture_stage >=
                             SVGA3D_NUM_TEXTURE_UNITS)) {
                        DRM_ERROR("Illegal texture/sampler unit %u.\n",
                                  (unsigned) bi->i1.texture_stage);
                        return -EINVAL;
                }
                loc = &cbs->texture_units[bi->i1.texture_stage];
                break;
        case vmw_ctx_binding_shader:
                if (unlikely((unsigned)bi->i1.shader_type >=
                             SVGA3D_SHADERTYPE_MAX)) {
                        DRM_ERROR("Illegal shader type %u.\n",
                                  (unsigned) bi->i1.shader_type);
                        return -EINVAL;
                }
                loc = &cbs->shaders[bi->i1.shader_type];
                break;
        default:
                BUG();
        }

        if (loc->bi.ctx != NULL)
                vmw_context_binding_drop(loc);

        loc->bi = *bi;
        loc->bi.scrubbed = false;
        list_add_tail(&loc->ctx_list, &cbs->list);
        INIT_LIST_HEAD(&loc->res_list);

        return 0;
}

/**
 * vmw_context_binding_transfer: Transfer a context binding tracking entry.
 *
 * @cbs: Pointer to the persistent context binding state tracker.
 * @bi: Information about the binding to track.
 *
 */
static void vmw_context_binding_transfer(struct vmw_ctx_binding_state *cbs,
                                         const struct vmw_ctx_bindinfo *bi)
{
        struct vmw_ctx_binding *loc;

        switch (bi->bt) {
        case vmw_ctx_binding_rt:
                loc = &cbs->render_targets[bi->i1.rt_type];
                break;
        case vmw_ctx_binding_tex:
                loc = &cbs->texture_units[bi->i1.texture_stage];
                break;
        case vmw_ctx_binding_shader:
                loc = &cbs->shaders[bi->i1.shader_type];
                break;
        default:
                BUG();
        }

        if (loc->bi.ctx != NULL)
                vmw_context_binding_drop(loc);

        if (bi->res != NULL) {
                loc->bi = *bi;
                list_add_tail(&loc->ctx_list, &cbs->list);
                list_add_tail(&loc->res_list, &bi->res->binding_head);
        }
}

/**
 * vmw_context_binding_kill - Kill a binding on the device
 * and stop tracking it.
 *
 * @cb: Pointer to binding tracker storage.
 *
 * Emits FIFO commands to scrub a binding represented by @cb.
 * Then stops tracking the binding and re-initializes its storage.
 */
static void vmw_context_binding_kill(struct vmw_ctx_binding *cb)
{
        if (!cb->bi.scrubbed) {
                (void) vmw_scrub_funcs[cb->bi.bt](&cb->bi, false);
                cb->bi.scrubbed = true;
        }
        vmw_context_binding_drop(cb);
}

/**
 * vmw_context_binding_state_kill - Kill all bindings associated with a
 * struct vmw_ctx_binding state structure, and re-initialize the structure.
 *
 * @cbs: Pointer to the context binding state tracker.
 *
 * Emits commands to scrub all bindings associated with the
 * context binding state tracker. Then re-initializes the whole structure.
 */
static void vmw_context_binding_state_kill(struct vmw_ctx_binding_state *cbs)
{
        struct vmw_ctx_binding *entry, *next;

        list_for_each_entry_safe(entry, next, &cbs->list, ctx_list)
                vmw_context_binding_kill(entry);
}

/**
 * vmw_context_binding_state_scrub - Scrub all bindings associated with a
 * struct vmw_ctx_binding state structure.
 *
 * @cbs: Pointer to the context binding state tracker.
 *
 * Emits commands to scrub all bindings associated with the
 * context binding state tracker.
 */
static void vmw_context_binding_state_scrub(struct vmw_ctx_binding_state *cbs)
{
        struct vmw_ctx_binding *entry;

        list_for_each_entry(entry, &cbs->list, ctx_list) {
                if (!entry->bi.scrubbed) {
                        (void) vmw_scrub_funcs[entry->bi.bt](&entry->bi, false);
                        entry->bi.scrubbed = true;
                }
        }
}

/**
 * vmw_context_binding_res_list_kill - Kill all bindings on a
 * resource binding list
 *
 * @head: list head of resource binding list
 *
 * Kills all bindings associated with a specific resource. Typically
 * called before the resource is destroyed.
 */
void vmw_context_binding_res_list_kill(struct list_head *head)
{
        struct vmw_ctx_binding *entry, *next;

        list_for_each_entry_safe(entry, next, head, res_list)
                vmw_context_binding_kill(entry);
}

/**
 * vmw_context_binding_res_list_scrub - Scrub all bindings on a
 * resource binding list
 *
 * @head: list head of resource binding list
 *
 * Scrub all bindings associated with a specific resource. Typically
 * called before the resource is evicted.
 */
void vmw_context_binding_res_list_scrub(struct list_head *head)
{
        struct vmw_ctx_binding *entry;

        list_for_each_entry(entry, head, res_list) {
                if (!entry->bi.scrubbed) {
                        (void) vmw_scrub_funcs[entry->bi.bt](&entry->bi, false);
                        entry->bi.scrubbed = true;
                }
        }
}

/**
 * vmw_context_binding_state_transfer - Commit staged binding info
 *
 * @ctx: Pointer to context to commit the staged binding info to.
 * @from: Staged binding info built during execbuf.
 *
 * Transfers binding info from a temporary structure to the persistent
 * structure in the context. This can be done once commands
 */
void vmw_context_binding_state_transfer(struct vmw_resource *ctx,
                                        struct vmw_ctx_binding_state *from)
{
        struct vmw_user_context *uctx =
                container_of(ctx, struct vmw_user_context, res);
        struct vmw_ctx_binding *entry, *next;

        list_for_each_entry_safe(entry, next, &from->list, ctx_list)
                vmw_context_binding_transfer(&uctx->cbs, &entry->bi);
}

/**
 * vmw_context_rebind_all - Rebind all scrubbed bindings of a context
 *
 * @ctx: The context resource
 *
 * Walks through the context binding list and rebinds all scrubbed
 * resources.
 */
int vmw_context_rebind_all(struct vmw_resource *ctx)
{
        struct vmw_ctx_binding *entry;
        struct vmw_user_context *uctx =
                container_of(ctx, struct vmw_user_context, res);
        struct vmw_ctx_binding_state *cbs = &uctx->cbs;
        int ret;

        list_for_each_entry(entry, &cbs->list, ctx_list) {
                if (likely(!entry->bi.scrubbed))
                        continue;

                if (WARN_ON(entry->bi.res == NULL || entry->bi.res->id ==
                            SVGA3D_INVALID_ID))
                        continue;

                ret = vmw_scrub_funcs[entry->bi.bt](&entry->bi, true);
                if (unlikely(ret != 0))
                        return ret;

                entry->bi.scrubbed = false;
        }

        return 0;
}

/**
 * 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)
{
        return &(container_of(ctx, struct vmw_user_context, res)->cbs.list);
}

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