diff options
Diffstat (limited to 'drivers/gpu/drm/virtio/virtgpu_vq.c')
| -rw-r--r-- | drivers/gpu/drm/virtio/virtgpu_vq.c | 26 |
1 files changed, 24 insertions, 2 deletions
diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c index 2c5eeccb88c0..6c1a90717535 100644 --- a/drivers/gpu/drm/virtio/virtgpu_vq.c +++ b/drivers/gpu/drm/virtio/virtgpu_vq.c @@ -593,12 +593,14 @@ static void virtio_gpu_cmd_capset_cb(struct virtio_gpu_device *vgdev, cache_ent->id == le32_to_cpu(cmd->capset_id)) { memcpy(cache_ent->caps_cache, resp->capset_data, cache_ent->size); + /* Copy must occur before is_valid is signalled. */ + smp_wmb(); atomic_set(&cache_ent->is_valid, 1); break; } } spin_unlock(&vgdev->display_info_lock); - wake_up(&vgdev->resp_wq); + wake_up_all(&vgdev->resp_wq); } static int virtio_get_edid_block(void *data, u8 *buf, @@ -694,8 +696,11 @@ int virtio_gpu_cmd_get_capset(struct virtio_gpu_device *vgdev, struct virtio_gpu_vbuffer *vbuf; int max_size; struct virtio_gpu_drv_cap_cache *cache_ent; + struct virtio_gpu_drv_cap_cache *search_ent; void *resp_buf; + *cache_p = NULL; + if (idx >= vgdev->num_capsets) return -EINVAL; @@ -726,9 +731,26 @@ int virtio_gpu_cmd_get_capset(struct virtio_gpu_device *vgdev, atomic_set(&cache_ent->is_valid, 0); cache_ent->size = max_size; spin_lock(&vgdev->display_info_lock); - list_add_tail(&cache_ent->head, &vgdev->cap_cache); + /* Search while under lock in case it was added by another task. */ + list_for_each_entry(search_ent, &vgdev->cap_cache, head) { + if (search_ent->id == vgdev->capsets[idx].id && + search_ent->version == version) { + *cache_p = search_ent; + break; + } + } + if (!*cache_p) + list_add_tail(&cache_ent->head, &vgdev->cap_cache); spin_unlock(&vgdev->display_info_lock); + if (*cache_p) { + /* Entry was found, so free everything that was just created. */ + kfree(resp_buf); + kfree(cache_ent->caps_cache); + kfree(cache_ent); + return 0; + } + cmd_p = virtio_gpu_alloc_cmd_resp (vgdev, &virtio_gpu_cmd_capset_cb, &vbuf, sizeof(*cmd_p), sizeof(struct virtio_gpu_resp_capset) + max_size, |