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 <trace/events/dma_fence.h>
 27
 28#include "virtgpu_drv.h"
 29
 30static const char *virtio_get_driver_name(struct dma_fence *f)
 31{
 32	return "virtio_gpu";
 33}
 34
 35static const char *virtio_get_timeline_name(struct dma_fence *f)
 36{
 37	return "controlq";
 38}
 39
 40bool virtio_fence_signaled(struct dma_fence *f)
 41{
 42	struct virtio_gpu_fence *fence = to_virtio_fence(f);
 43
 44	if (atomic64_read(&fence->drv->last_seq) >= fence->f.seqno)
 45		return true;
 46	return false;
 47}
 48
 49static void virtio_fence_value_str(struct dma_fence *f, char *str, int size)
 50{
 51	snprintf(str, size, "%llu", f->seqno);
 52}
 53
 54static void virtio_timeline_value_str(struct dma_fence *f, char *str, int size)
 55{
 56	struct virtio_gpu_fence *fence = to_virtio_fence(f);
 57
 58	snprintf(str, size, "%llu", (u64)atomic64_read(&fence->drv->last_seq));
 59}
 60
 61static const struct dma_fence_ops virtio_fence_ops = {
 62	.get_driver_name     = virtio_get_driver_name,
 63	.get_timeline_name   = virtio_get_timeline_name,
 64	.signaled            = virtio_fence_signaled,
 65	.fence_value_str     = virtio_fence_value_str,
 66	.timeline_value_str  = virtio_timeline_value_str,
 67};
 68
 69struct virtio_gpu_fence *virtio_gpu_fence_alloc(struct virtio_gpu_device *vgdev)
 70{
 71	struct virtio_gpu_fence_driver *drv = &vgdev->fence_drv;
 72	struct virtio_gpu_fence *fence = kzalloc(sizeof(struct virtio_gpu_fence),
 73							GFP_KERNEL);
 74	if (!fence)
 75		return fence;
 76
 77	fence->drv = drv;
 78
 79	/* This only partially initializes the fence because the seqno is
 80	 * unknown yet.  The fence must not be used outside of the driver
 81	 * until virtio_gpu_fence_emit is called.
 82	 */
 83	dma_fence_init(&fence->f, &virtio_fence_ops, &drv->lock, drv->context, 0);
 84
 85	return fence;
 86}
 87
 88void virtio_gpu_fence_emit(struct virtio_gpu_device *vgdev,
 89			  struct virtio_gpu_ctrl_hdr *cmd_hdr,
 90			  struct virtio_gpu_fence *fence)
 91{
 92	struct virtio_gpu_fence_driver *drv = &vgdev->fence_drv;
 93	unsigned long irq_flags;
 94
 95	spin_lock_irqsave(&drv->lock, irq_flags);
 96	fence->f.seqno = ++drv->sync_seq;
 97	dma_fence_get(&fence->f);
 98	list_add_tail(&fence->node, &drv->fences);
 99	spin_unlock_irqrestore(&drv->lock, irq_flags);
100
101	trace_dma_fence_emit(&fence->f);
102
103	cmd_hdr->flags |= cpu_to_le32(VIRTIO_GPU_FLAG_FENCE);
104	cmd_hdr->fence_id = cpu_to_le64(fence->f.seqno);
105}
106
107void virtio_gpu_fence_event_process(struct virtio_gpu_device *vgdev,
108				    u64 last_seq)
109{
110	struct virtio_gpu_fence_driver *drv = &vgdev->fence_drv;
111	struct virtio_gpu_fence *fence, *tmp;
112	unsigned long irq_flags;
113
114	spin_lock_irqsave(&drv->lock, irq_flags);
115	atomic64_set(&vgdev->fence_drv.last_seq, last_seq);
116	list_for_each_entry_safe(fence, tmp, &drv->fences, node) {
117		if (last_seq < fence->f.seqno)
118			continue;
119		dma_fence_signal_locked(&fence->f);
120		list_del(&fence->node);
121		dma_fence_put(&fence->f);
122	}
123	spin_unlock_irqrestore(&drv->lock, irq_flags);
124}