+
+/**
+ * vmw_resource_buf_alloc - Allocate a backup buffer for a resource.
+ *
+ * @res: The resource for which to allocate a backup buffer.
+ * @interruptible: Whether any sleeps during allocation should be
+ * performed while interruptible.
+ */
+static int vmw_resource_buf_alloc(struct vmw_resource *res,
+ bool interruptible)
+{
+ unsigned long size =
+ (res->backup_size + PAGE_SIZE - 1) & PAGE_MASK;
+ struct vmw_dma_buffer *backup;
+ int ret;
+
+ if (likely(res->backup)) {
+ BUG_ON(res->backup->base.num_pages * PAGE_SIZE < size);
+ return 0;
+ }
+
+ backup = kzalloc(sizeof(*backup), GFP_KERNEL);
+ if (unlikely(backup == NULL))
+ return -ENOMEM;
+
+ ret = vmw_dmabuf_init(res->dev_priv, backup, res->backup_size,
+ res->func->backup_placement,
+ interruptible,
+ &vmw_dmabuf_bo_free);
+ if (unlikely(ret != 0))
+ goto out_no_dmabuf;
+
+ res->backup = backup;
+
+out_no_dmabuf:
+ return ret;
+}
+
+/**
+ * vmw_resource_do_validate - Make a resource up-to-date and visible
+ * to the device.
+ *
+ * @res: The resource to make visible to the device.
+ * @val_buf: Information about a buffer possibly
+ * containing backup data if a bind operation is needed.
+ *
+ * On hardware resource shortage, this function returns -EBUSY and
+ * should be retried once resources have been freed up.
+ */
+static int vmw_resource_do_validate(struct vmw_resource *res,
+ struct ttm_validate_buffer *val_buf)
+{
+ int ret = 0;
+ const struct vmw_res_func *func = res->func;
+
+ if (unlikely(res->id == -1)) {
+ ret = func->create(res);
+ if (unlikely(ret != 0))
+ return ret;
+ }
+
+ if (func->bind &&
+ ((func->needs_backup && list_empty(&res->mob_head) &&
+ val_buf->bo != NULL) ||
+ (!func->needs_backup && val_buf->bo != NULL))) {
+ ret = func->bind(res, val_buf);
+ if (unlikely(ret != 0))
+ goto out_bind_failed;
+ if (func->needs_backup)
+ list_add_tail(&res->mob_head, &res->backup->res_list);
+ }
+
+ /*
+ * Only do this on write operations, and move to
+ * vmw_resource_unreserve if it can be called after
+ * backup buffers have been unreserved. Otherwise
+ * sort out locking.
+ */
+ res->res_dirty = true;
+
+ return 0;
+
+out_bind_failed:
+ func->destroy(res);
+
+ return ret;
+}
+
+/**
+ * vmw_resource_unreserve - Unreserve a resource previously reserved for
+ * command submission.
+ *
+ * @res: Pointer to the struct vmw_resource to unreserve.
+ * @new_backup: Pointer to new backup buffer if command submission
+ * switched.
+ * @new_backup_offset: New backup offset if @new_backup is !NULL.
+ *
+ * Currently unreserving a resource means putting it back on the device's
+ * resource lru list, so that it can be evicted if necessary.
+ */
+void vmw_resource_unreserve(struct vmw_resource *res,
+ struct vmw_dma_buffer *new_backup,
+ unsigned long new_backup_offset)
+{
+ struct vmw_private *dev_priv = res->dev_priv;
+
+ if (!list_empty(&res->lru_head))
+ return;
+
+ if (new_backup && new_backup != res->backup) {
+
+ if (res->backup) {
+ BUG_ON(atomic_read(&res->backup->base.reserved) == 0);
+ list_del_init(&res->mob_head);
+ vmw_dmabuf_unreference(&res->backup);
+ }
+
+ res->backup = vmw_dmabuf_reference(new_backup);
+ BUG_ON(atomic_read(&new_backup->base.reserved) == 0);
+ list_add_tail(&res->mob_head, &new_backup->res_list);
+ }
+ if (new_backup)
+ res->backup_offset = new_backup_offset;
+
+ if (!res->func->may_evict)
+ return;
+
+ write_lock(&dev_priv->resource_lock);
+ list_add_tail(&res->lru_head,
+ &res->dev_priv->res_lru[res->func->res_type]);
+ write_unlock(&dev_priv->resource_lock);
+}
+
+/**
+ * vmw_resource_check_buffer - Check whether a backup buffer is needed
+ * for a resource and in that case, allocate
+ * one, reserve and validate it.
+ *
+ * @res: The resource for which to allocate a backup buffer.
+ * @interruptible: Whether any sleeps during allocation should be
+ * performed while interruptible.
+ * @val_buf: On successful return contains data about the
+ * reserved and validated backup buffer.
+ */
+int vmw_resource_check_buffer(struct vmw_resource *res,
+ bool interruptible,
+ struct ttm_validate_buffer *val_buf)
+{
+ struct list_head val_list;
+ bool backup_dirty = false;
+ int ret;
+
+ if (unlikely(res->backup == NULL)) {
+ ret = vmw_resource_buf_alloc(res, interruptible);
+ if (unlikely(ret != 0))
+ return ret;
+ }
+
+ INIT_LIST_HEAD(&val_list);
+ val_buf->bo = ttm_bo_reference(&res->backup->base);
+ list_add_tail(&val_buf->head, &val_list);
+ ret = ttm_eu_reserve_buffers(&val_list);
+ if (unlikely(ret != 0))
+ goto out_no_reserve;
+
+ if (res->func->needs_backup && list_empty(&res->mob_head))
+ return 0;
+
+ backup_dirty = res->backup_dirty;
+ ret = ttm_bo_validate(&res->backup->base,
+ res->func->backup_placement,
+ true, false, false);
+
+ if (unlikely(ret != 0))
+ goto out_no_validate;
+
+ return 0;
+
+out_no_validate:
+ ttm_eu_backoff_reservation(&val_list);
+out_no_reserve:
+ ttm_bo_unref(&val_buf->bo);
+ if (backup_dirty)
+ vmw_dmabuf_unreference(&res->backup);
+
+ return ret;
+}
+
+/**
+ * vmw_resource_reserve - Reserve a resource for command submission
+ *
+ * @res: The resource to reserve.
+ *
+ * This function takes the resource off the LRU list and make sure
+ * a backup buffer is present for guest-backed resources. However,
+ * the buffer may not be bound to the resource at this point.
+ *
+ */
+int vmw_resource_reserve(struct vmw_resource *res, bool no_backup)
+{
+ struct vmw_private *dev_priv = res->dev_priv;
+ int ret;
+
+ write_lock(&dev_priv->resource_lock);
+ list_del_init(&res->lru_head);
+ write_unlock(&dev_priv->resource_lock);
+
+ if (res->func->needs_backup && res->backup == NULL &&
+ !no_backup) {
+ ret = vmw_resource_buf_alloc(res, true);
+ if (unlikely(ret != 0))
+ return ret;
+ }
+
+ return 0;
+}
+
+/**
+ * vmw_resource_backoff_reservation - Unreserve and unreference a
+ * backup buffer
+ *.
+ * @val_buf: Backup buffer information.
+ */
+void vmw_resource_backoff_reservation(struct ttm_validate_buffer *val_buf)
+{
+ struct list_head val_list;
+
+ if (likely(val_buf->bo == NULL))
+ return;
+
+ INIT_LIST_HEAD(&val_list);
+ list_add_tail(&val_buf->head, &val_list);
+ ttm_eu_backoff_reservation(&val_list);
+ ttm_bo_unref(&val_buf->bo);
+}
+
+/**
+ * vmw_resource_do_evict - Evict a resource, and transfer its data
+ * to a backup buffer.
+ *
+ * @res: The resource to evict.
+ */
+int vmw_resource_do_evict(struct vmw_resource *res)
+{
+ struct ttm_validate_buffer val_buf;
+ const struct vmw_res_func *func = res->func;
+ int ret;
+
+ BUG_ON(!func->may_evict);
+
+ val_buf.bo = NULL;
+ ret = vmw_resource_check_buffer(res, true, &val_buf);
+ if (unlikely(ret != 0))
+ return ret;
+
+ if (unlikely(func->unbind != NULL &&
+ (!func->needs_backup || !list_empty(&res->mob_head)))) {
+ ret = func->unbind(res, res->res_dirty, &val_buf);
+ if (unlikely(ret != 0))
+ goto out_no_unbind;
+ list_del_init(&res->mob_head);
+ }
+ ret = func->destroy(res);
+ res->backup_dirty = true;
+ res->res_dirty = false;
+out_no_unbind:
+ vmw_resource_backoff_reservation(&val_buf);
+
+ return ret;
+}
+
+
+/**
+ * vmw_resource_validate - Make a resource up-to-date and visible
+ * to the device.
+ *
+ * @res: The resource to make visible to the device.
+ *
+ * On succesful return, any backup DMA buffer pointed to by @res->backup will
+ * be reserved and validated.
+ * On hardware resource shortage, this function will repeatedly evict
+ * resources of the same type until the validation succeeds.
+ */
+int vmw_resource_validate(struct vmw_resource *res)
+{
+ int ret;
+ struct vmw_resource *evict_res;
+ struct vmw_private *dev_priv = res->dev_priv;
+ struct list_head *lru_list = &dev_priv->res_lru[res->func->res_type];
+ struct ttm_validate_buffer val_buf;
+
+ if (likely(!res->func->may_evict))
+ return 0;
+
+ val_buf.bo = NULL;
+ if (res->backup)
+ val_buf.bo = &res->backup->base;
+ do {
+ ret = vmw_resource_do_validate(res, &val_buf);
+ if (likely(ret != -EBUSY))
+ break;
+
+ write_lock(&dev_priv->resource_lock);
+ if (list_empty(lru_list) || !res->func->may_evict) {
+ DRM_ERROR("Out of device device id entries "
+ "for %s.\n", res->func->type_name);
+ ret = -EBUSY;
+ write_unlock(&dev_priv->resource_lock);
+ break;
+ }
+
+ evict_res = vmw_resource_reference
+ (list_first_entry(lru_list, struct vmw_resource,
+ lru_head));
+ list_del_init(&evict_res->lru_head);
+
+ write_unlock(&dev_priv->resource_lock);
+ vmw_resource_do_evict(evict_res);
+ vmw_resource_unreference(&evict_res);
+ } while (1);
+
+ if (unlikely(ret != 0))
+ goto out_no_validate;
+ else if (!res->func->needs_backup && res->backup) {
+ list_del_init(&res->mob_head);
+ vmw_dmabuf_unreference(&res->backup);
+ }
+
+ return 0;
+
+out_no_validate:
+ return ret;
+}
+
+/**
+ * vmw_fence_single_bo - Utility function to fence a single TTM buffer
+ * object without unreserving it.
+ *
+ * @bo: Pointer to the struct ttm_buffer_object to fence.
+ * @fence: Pointer to the fence. If NULL, this function will
+ * insert a fence into the command stream..
+ *
+ * Contrary to the ttm_eu version of this function, it takes only
+ * a single buffer object instead of a list, and it also doesn't
+ * unreserve the buffer object, which needs to be done separately.
+ */
+void vmw_fence_single_bo(struct ttm_buffer_object *bo,
+ struct vmw_fence_obj *fence)
+{
+ struct ttm_bo_device *bdev = bo->bdev;
+ struct ttm_bo_driver *driver = bdev->driver;
+ struct vmw_fence_obj *old_fence_obj;
+ struct vmw_private *dev_priv =
+ container_of(bdev, struct vmw_private, bdev);
+
+ if (fence == NULL)
+ vmw_execbuf_fence_commands(NULL, dev_priv, &fence, NULL);
+ else
+ driver->sync_obj_ref(fence);
+
+ spin_lock(&bdev->fence_lock);
+
+ old_fence_obj = bo->sync_obj;
+ bo->sync_obj = fence;
+
+ spin_unlock(&bdev->fence_lock);
+
+ if (old_fence_obj)
+ vmw_fence_obj_unreference(&old_fence_obj);
+}
+
+/**
+ * vmw_resource_move_notify - TTM move_notify_callback
+ *
+ * @bo: The TTM buffer object about to move.
+ * @mem: The truct ttm_mem_reg indicating to what memory
+ * region the move is taking place.
+ *
+ * For now does nothing.
+ */
+void vmw_resource_move_notify(struct ttm_buffer_object *bo,
+ struct ttm_mem_reg *mem)
+{
+}
+
+/**
+ * vmw_resource_needs_backup - Return whether a resource needs a backup buffer.
+ *
+ * @res: The resource being queried.
+ */
+bool vmw_resource_needs_backup(const struct vmw_resource *res)
+{
+ return res->func->needs_backup;
+}
+
+/**
+ * vmw_resource_evict_type - Evict all resources of a specific type
+ *
+ * @dev_priv: Pointer to a device private struct
+ * @type: The resource type to evict
+ *
+ * To avoid thrashing starvation or as part of the hibernation sequence,
+ * evict all evictable resources of a specific type.
+ */
+static void vmw_resource_evict_type(struct vmw_private *dev_priv,
+ enum vmw_res_type type)
+{
+ struct list_head *lru_list = &dev_priv->res_lru[type];
+ struct vmw_resource *evict_res;
+
+ do {
+ write_lock(&dev_priv->resource_lock);
+
+ if (list_empty(lru_list))
+ goto out_unlock;
+
+ evict_res = vmw_resource_reference(
+ list_first_entry(lru_list, struct vmw_resource,
+ lru_head));
+ list_del_init(&evict_res->lru_head);
+ write_unlock(&dev_priv->resource_lock);
+ vmw_resource_do_evict(evict_res);
+ vmw_resource_unreference(&evict_res);
+ } while (1);
+
+out_unlock:
+ write_unlock(&dev_priv->resource_lock);
+}
+
+/**
+ * vmw_resource_evict_all - Evict all evictable resources
+ *
+ * @dev_priv: Pointer to a device private struct
+ *
+ * To avoid thrashing starvation or as part of the hibernation sequence,
+ * evict all evictable resources. In particular this means that all
+ * guest-backed resources that are registered with the device are
+ * evicted and the OTable becomes clean.
+ */
+void vmw_resource_evict_all(struct vmw_private *dev_priv)
+{
+ enum vmw_res_type type;
+
+ mutex_lock(&dev_priv->cmdbuf_mutex);
+
+ for (type = 0; type < vmw_res_max; ++type)
+ vmw_resource_evict_type(dev_priv, type);
+
+ mutex_unlock(&dev_priv->cmdbuf_mutex);
+}