LXR linux/drivers/gpu/drm/virtio/virtgpu

   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
  30#define to_virtio_gpu_fence(x) \
  31        container_of(x, struct virtio_gpu_fence, f)
  32
  33static const char *virtio_gpu_get_driver_name(struct dma_fence *f)
  34{
  35        return "virtio_gpu";
  36}
  37
  38static const char *virtio_gpu_get_timeline_name(struct dma_fence *f)
  39{
  40        return "controlq";
  41}
  42
  43static bool virtio_gpu_fence_signaled(struct dma_fence *f)
  44{
  45        /* leaked fence outside driver before completing
  46         * initialization with virtio_gpu_fence_emit.
  47         */
  48        WARN_ON_ONCE(f->seqno == 0);
  49        return false;
  50}
  51
  52static void virtio_gpu_fence_value_str(struct dma_fence *f, char *str, int size)
  53{
  54        snprintf(str, size, "[%llu, %llu]", f->context, f->seqno);
  55}
  56
  57static void virtio_gpu_timeline_value_str(struct dma_fence *f, char *str,
  58                                          int size)
  59{
  60        struct virtio_gpu_fence *fence = to_virtio_gpu_fence(f);
  61
  62        snprintf(str, size, "%llu",
  63                 (u64)atomic64_read(&fence->drv->last_fence_id));
  64}
  65
  66static const struct dma_fence_ops virtio_gpu_fence_ops = {
  67        .get_driver_name     = virtio_gpu_get_driver_name,
  68        .get_timeline_name   = virtio_gpu_get_timeline_name,
  69        .signaled            = virtio_gpu_fence_signaled,
  70        .fence_value_str     = virtio_gpu_fence_value_str,
  71        .timeline_value_str  = virtio_gpu_timeline_value_str,
  72};
  73
  74struct virtio_gpu_fence *virtio_gpu_fence_alloc(struct virtio_gpu_device *vgdev)
  75{
  76        struct virtio_gpu_fence_driver *drv = &vgdev->fence_drv;
  77        struct virtio_gpu_fence *fence = kzalloc(sizeof(struct virtio_gpu_fence),
  78                                                        GFP_KERNEL);
  79        if (!fence)
  80                return fence;
  81
  82        fence->drv = drv;
  83
  84        /* This only partially initializes the fence because the seqno is
  85         * unknown yet.  The fence must not be used outside of the driver
  86         * until virtio_gpu_fence_emit is called.
  87         */
  88        dma_fence_init(&fence->f, &virtio_gpu_fence_ops, &drv->lock, drv->context,
  89                       0);
  90
  91        return fence;
  92}
  93
  94void virtio_gpu_fence_emit(struct virtio_gpu_device *vgdev,
  95                          struct virtio_gpu_ctrl_hdr *cmd_hdr,
  96                          struct virtio_gpu_fence *fence)
  97{
  98        struct virtio_gpu_fence_driver *drv = &vgdev->fence_drv;
  99        unsigned long irq_flags;
 100
 101        spin_lock_irqsave(&drv->lock, irq_flags);
 102        fence->fence_id = fence->f.seqno = ++drv->current_fence_id;
 103        dma_fence_get(&fence->f);
 104        list_add_tail(&fence->node, &drv->fences);
 105        spin_unlock_irqrestore(&drv->lock, irq_flags);
 106
 107        trace_dma_fence_emit(&fence->f);
 108
 109        cmd_hdr->flags |= cpu_to_le32(VIRTIO_GPU_FLAG_FENCE);
 110        cmd_hdr->fence_id = cpu_to_le64(fence->fence_id);
 111}
 112
 113void virtio_gpu_fence_event_process(struct virtio_gpu_device *vgdev,
 114                                    u64 fence_id)
 115{
 116        struct virtio_gpu_fence_driver *drv = &vgdev->fence_drv;
 117        struct virtio_gpu_fence *signaled, *curr, *tmp;
 118        unsigned long irq_flags;
 119
 120        spin_lock_irqsave(&drv->lock, irq_flags);
 121        atomic64_set(&vgdev->fence_drv.last_fence_id, fence_id);
 122        list_for_each_entry_safe(curr, tmp, &drv->fences, node) {
 123                if (fence_id != curr->fence_id)
 124                        continue;
 125
 126                signaled = curr;
 127
 128                /*
 129                 * Signal any fences with a strictly smaller sequence number
 130                 * than the current signaled fence.
 131                 */
 132                list_for_each_entry_safe(curr, tmp, &drv->fences, node) {
 133                        /* dma-fence contexts must match */
 134                        if (signaled->f.context != curr->f.context)
 135                                continue;
 136
 137                        if (!dma_fence_is_later(&signaled->f, &curr->f))
 138                                continue;
 139
 140                        dma_fence_signal_locked(&curr->f);
 141                        list_del(&curr->node);
 142                        dma_fence_put(&curr->f);
 143                }
 144
 145                dma_fence_signal_locked(&signaled->f);
 146                list_del(&signaled->node);
 147                dma_fence_put(&signaled->f);
 148                break;
 149        }
 150        spin_unlock_irqrestore(&drv->lock, irq_flags);
 151}
 152