1/*
  2 * Copyright (C) 2015 Red Hat, Inc.
  3 * All Rights Reserved.
  4 *
  5 * Permission is hereby granted, free of charge, to any person obtaining
  6 * a copy of this software and associated documentation files (the
  7 * "Software"), to deal in the Software without restriction, including
  8 * without limitation the rights to use, copy, modify, merge, publish,
  9 * distribute, sublicense, and/or sell copies of the Software, and to
 10 * permit persons to whom the Software is furnished to do so, subject to
 11 * the following conditions:
 12 *
 13 * The above copyright notice and this permission notice (including the
 14 * next paragraph) shall be included in all copies or substantial
 15 * portions of the Software.
 16 *
 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 20 * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
 21 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 22 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 23 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 24 */
 25
 26#include <drm/drmP.h>
 27#include "virtgpu_drv.h"
 28
 29static const char *virtio_get_driver_name(struct dma_fence *f)
 30{
 31	return "virtio_gpu";
 32}
 33
 34static const char *virtio_get_timeline_name(struct dma_fence *f)
 35{
 36	return "controlq";
 37}
 38
 39static bool virtio_enable_signaling(struct dma_fence *f)
 40{
 41	return true;
 42}
 43
 44static bool virtio_signaled(struct dma_fence *f)
 45{
 46	struct virtio_gpu_fence *fence = to_virtio_fence(f);
 47
 48	if (atomic64_read(&fence->drv->last_seq) >= fence->seq)
 49		return true;
 50	return false;
 51}
 52
 53static void virtio_fence_value_str(struct dma_fence *f, char *str, int size)
 54{
 55	struct virtio_gpu_fence *fence = to_virtio_fence(f);
 56
 57	snprintf(str, size, "%llu", fence->seq);
 58}
 59
 60static void virtio_timeline_value_str(struct dma_fence *f, char *str, int size)
 61{
 62	struct virtio_gpu_fence *fence = to_virtio_fence(f);
 63
 64	snprintf(str, size, "%llu", (u64)atomic64_read(&fence->drv->last_seq));
 65}
 66
 67static const struct dma_fence_ops virtio_fence_ops = {
 68	.get_driver_name     = virtio_get_driver_name,
 69	.get_timeline_name   = virtio_get_timeline_name,
 70	.enable_signaling    = virtio_enable_signaling,
 71	.signaled            = virtio_signaled,
 72	.wait                = dma_fence_default_wait,
 73	.fence_value_str     = virtio_fence_value_str,
 74	.timeline_value_str  = virtio_timeline_value_str,
 75};
 76
 77int virtio_gpu_fence_emit(struct virtio_gpu_device *vgdev,
 78			  struct virtio_gpu_ctrl_hdr *cmd_hdr,
 79			  struct virtio_gpu_fence **fence)
 80{
 81	struct virtio_gpu_fence_driver *drv = &vgdev->fence_drv;
 82	unsigned long irq_flags;
 83
 84	*fence = kmalloc(sizeof(struct virtio_gpu_fence), GFP_ATOMIC);
 85	if ((*fence) == NULL)
 86		return -ENOMEM;
 87
 88	spin_lock_irqsave(&drv->lock, irq_flags);
 89	(*fence)->drv = drv;
 90	(*fence)->seq = ++drv->sync_seq;
 91	dma_fence_init(&(*fence)->f, &virtio_fence_ops, &drv->lock,
 92		       drv->context, (*fence)->seq);
 93	dma_fence_get(&(*fence)->f);
 94	list_add_tail(&(*fence)->node, &drv->fences);
 95	spin_unlock_irqrestore(&drv->lock, irq_flags);
 96
 97	cmd_hdr->flags |= cpu_to_le32(VIRTIO_GPU_FLAG_FENCE);
 98	cmd_hdr->fence_id = cpu_to_le64((*fence)->seq);
 99	return 0;
100}
101
102void virtio_gpu_fence_event_process(struct virtio_gpu_device *vgdev,
103				    u64 last_seq)
104{
105	struct virtio_gpu_fence_driver *drv = &vgdev->fence_drv;
106	struct virtio_gpu_fence *fence, *tmp;
107	unsigned long irq_flags;
108
109	spin_lock_irqsave(&drv->lock, irq_flags);
110	atomic64_set(&vgdev->fence_drv.last_seq, last_seq);
111	list_for_each_entry_safe(fence, tmp, &drv->fences, node) {
112		if (last_seq < fence->seq)
113			continue;
114		dma_fence_signal_locked(&fence->f);
115		list_del(&fence->node);
116		dma_fence_put(&fence->f);
117	}
118	spin_unlock_irqrestore(&drv->lock, irq_flags);
119}