On 2019/9/6 3:48, Vivek Goyal wrote:
> This object is used both by fuse_connection as well virt device. So make
> this object reference counted and that makes it easy to define life cycle
> of the object.
>
> Now deivce can be removed while filesystem is still mounted. This will
> cleanup all the virtqueues but virtio_fs object will still be around and
> will be cleaned when filesystem is unmounted and sb/fc drops its reference.
>
> Removing a device also stops all virt queues and any new reuqest gets
> error -ENOTCONN. All existing in flight requests are drained before
> ->remove returns.
>
> Signed-off-by: Vivek Goyal <vgoyal@xxxxxxxxxx>
> ---
> fs/fuse/virtio_fs.c | 52 +++++++++++++++++++++++++++++++++++++--------
> 1 file changed, 43 insertions(+), 9 deletions(-)
>
> diff --git a/fs/fuse/virtio_fs.c b/fs/fuse/virtio_fs.c
> index 01bbf2c0e144..29ec2f5bbbe2 100644
> --- a/fs/fuse/virtio_fs.c
> +++ b/fs/fuse/virtio_fs.c
> @@ -37,6 +37,7 @@ struct virtio_fs_vq {
>
> /* A virtio-fs device instance */
> struct virtio_fs {
> + struct kref refcount;
> struct list_head list; /* on virtio_fs_instances */
> char *tag;
> struct virtio_fs_vq *vqs;
> @@ -63,6 +64,27 @@ static inline struct fuse_pqueue *vq_to_fpq(struct virtqueue *vq)
> return &vq_to_fsvq(vq)->fud->pq;
> }
>
> +static void release_virtiofs_obj(struct kref *ref)
> +{
> + struct virtio_fs *vfs = container_of(ref, struct virtio_fs, refcount);
> +
> + kfree(vfs->vqs);
> + kfree(vfs);
> +}
> +
> +static void virtio_fs_put(struct virtio_fs *fs)
> +{
> + mutex_lock(&virtio_fs_mutex);
> + kref_put(&fs->refcount, release_virtiofs_obj);
> + mutex_unlock(&virtio_fs_mutex);
> +}
> +
> +static void virtio_fs_put(struct fuse_iqueue *fiq)
> +{
> + struct virtio_fs *vfs = fiq->priv;
> + virtiofs_put(vfs);
> +}
It's a little confusing that virtiofs_put() looks like virtiofs_put(),
and could we use __virtio_fs_put to replace virtio_fs_put?
Thanks,
Jun
