diff options
author | Jason Wang <jasowang@redhat.com> | 2022-05-27 09:01:18 +0300 |
---|---|---|
committer | Michael S. Tsirkin <mst@redhat.com> | 2022-05-31 19:45:10 +0300 |
commit | be83f04d2529e8dc4273efdd1ccf7b7502741071 (patch) | |
tree | c8ac489e26495a193e1158325698cd069a8ff3f3 | |
parent | 3a232277c1ac6df70552129a9722abc6ab250128 (diff) | |
download | linux-be83f04d2529e8dc4273efdd1ccf7b7502741071.tar.xz |
virtio: allow to unbreak virtqueue
This patch allows the new introduced __virtio_break_device() to
unbreak the virtqueue.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Halil Pasic <pasic@linux.ibm.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Vineeth Vijayan <vneethv@linux.ibm.com>
Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: linux-s390@vger.kernel.org
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220527060120.20964-8-jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
-rw-r--r-- | drivers/virtio/virtio_ring.c | 22 | ||||
-rw-r--r-- | include/linux/virtio.h | 1 |
2 files changed, 23 insertions, 0 deletions
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 9d0bae4293be..9c231e1fded7 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -2395,6 +2395,28 @@ void virtio_break_device(struct virtio_device *dev) } EXPORT_SYMBOL_GPL(virtio_break_device); +/* + * This should allow the device to be used by the driver. You may + * need to grab appropriate locks to flush the write to + * vq->broken. This should only be used in some specific case e.g + * (probing and restoring). This function should only be called by the + * core, not directly by the driver. + */ +void __virtio_unbreak_device(struct virtio_device *dev) +{ + struct virtqueue *_vq; + + spin_lock(&dev->vqs_list_lock); + list_for_each_entry(_vq, &dev->vqs, list) { + struct vring_virtqueue *vq = to_vvq(_vq); + + /* Pairs with READ_ONCE() in virtqueue_is_broken(). */ + WRITE_ONCE(vq->broken, false); + } + spin_unlock(&dev->vqs_list_lock); +} +EXPORT_SYMBOL_GPL(__virtio_unbreak_device); + dma_addr_t virtqueue_get_desc_addr(struct virtqueue *_vq) { struct vring_virtqueue *vq = to_vvq(_vq); diff --git a/include/linux/virtio.h b/include/linux/virtio.h index 5464f398912a..d8fdf170637c 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -131,6 +131,7 @@ void unregister_virtio_device(struct virtio_device *dev); bool is_virtio_device(struct device *dev); void virtio_break_device(struct virtio_device *dev); +void __virtio_unbreak_device(struct virtio_device *dev); void virtio_config_changed(struct virtio_device *dev); #ifdef CONFIG_PM_SLEEP |