diff options
| -rw-r--r-- | drivers/gpu/drm/virtio/virtgpu_vq.c | 22 |
1 files changed, 21 insertions, 1 deletions
diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c index 2bac1cbc5ec8..5de38b2ee9ac 100644 --- a/drivers/gpu/drm/virtio/virtgpu_vq.c +++ b/drivers/gpu/drm/virtio/virtgpu_vq.c @@ -694,8 +694,11 @@ 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 +729,26 @@ 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, |