[PATCH v3 28/28] vhost: add VDUSE device stop

[Maxime Coquelin]

On 5/29/23 08:53, Xia, Chenbo wrote:
> Hi Maxime,
> 
>> -----Original Message-----
>> From: Maxime Coquelin <maxime.coquelin at redhat.com>
>> Sent: Friday, May 26, 2023 12:26 AM
>> To: dev at dpdk.org; Xia, Chenbo <chenbo.xia at intel.com>;
>> david.marchand at redhat.com; mkp at redhat.com; fbl at redhat.com;
>> jasowang at redhat.com; Liang, Cunming <cunming.liang at intel.com>; Xie, Yongji
>> <xieyongji at bytedance.com>; echaudro at redhat.com; eperezma at redhat.com;
>> amorenoz at redhat.com; lulu at redhat.com
>> Cc: Maxime Coquelin <maxime.coquelin at redhat.com>
>> Subject: [PATCH v3 28/28] vhost: add VDUSE device stop
>>
>> This patch adds VDUSE device stop and cleanup of its
>> virtqueues.
>>
>> Signed-off-by: Maxime Coquelin <maxime.coquelin at redhat.com>
>> ---
>>   doc/guides/rel_notes/release_23_07.rst |  6 +++
>>   lib/vhost/vduse.c                      | 72 +++++++++++++++++++++++---
>>   2 files changed, 70 insertions(+), 8 deletions(-)
>>
>> diff --git a/doc/guides/rel_notes/release_23_07.rst
>> b/doc/guides/rel_notes/release_23_07.rst
>> index fa889a5ee7..66ba9e25dd 100644
>> --- a/doc/guides/rel_notes/release_23_07.rst
>> +++ b/doc/guides/rel_notes/release_23_07.rst
>> @@ -60,6 +60,12 @@ New Features
>>     Introduced ``rte_vhost_driver_set_max_queue_num()`` to be able to limit
>> the
>>     maximum number of supported queue pairs, required for VDUSE support.
>>
>> +* **Added VDUSE support into Vhost library
> 
> Missing '.**' at the end like patch 15

Fixed.

Thanks,
Maxime

> Thanks,
> Chenbo
> 
>> +
>> +  VDUSE aims at implementing vDPA devices in userspace. It can be used as
>> an
>> +  alternative to Vhost-user when using Vhost-vDPA, but also enable
>> providing a
>> +  virtio-net netdev to the host when using Virtio-vDPA driver.
>> +
>>
>>   Removed Items
>>   -------------
>> diff --git a/lib/vhost/vduse.c b/lib/vhost/vduse.c
>> index 699cfed9e3..f421b1cf4c 100644
>> --- a/lib/vhost/vduse.c
>> +++ b/lib/vhost/vduse.c
>> @@ -252,6 +252,44 @@ vduse_vring_setup(struct virtio_net *dev, unsigned
>> int index)
>>   	}
>>   }
>>
>> +static void
>> +vduse_vring_cleanup(struct virtio_net *dev, unsigned int index)
>> +{
>> +	struct vhost_virtqueue *vq = dev->virtqueue[index];
>> +	struct vduse_vq_eventfd vq_efd;
>> +	int ret;
>> +
>> +	if (vq == dev->cvq && vq->kickfd >= 0) {
>> +		fdset_del(&vduse.fdset, vq->kickfd);
>> +		fdset_pipe_notify(&vduse.fdset);
>> +	}
>> +
>> +	vq_efd.index = index;
>> +	vq_efd.fd = VDUSE_EVENTFD_DEASSIGN;
>> +
>> +	ret = ioctl(dev->vduse_dev_fd, VDUSE_VQ_SETUP_KICKFD, &vq_efd);
>> +	if (ret)
>> +		VHOST_LOG_CONFIG(dev->ifname, ERR, "Failed to cleanup kickfd
>> for VQ %u: %s\n",
>> +				index, strerror(errno));
>> +
>> +	close(vq->kickfd);
>> +	vq->kickfd = VIRTIO_UNINITIALIZED_EVENTFD;
>> +
>> +	vring_invalidate(dev, vq);
>> +
>> +	rte_free(vq->batch_copy_elems);
>> +	vq->batch_copy_elems = NULL;
>> +
>> +	rte_free(vq->shadow_used_split);
>> +	vq->shadow_used_split = NULL;
>> +
>> +	vq->enabled = false;
>> +	vq->ready = false;
>> +	vq->size = 0;
>> +	vq->last_used_idx = 0;
>> +	vq->last_avail_idx = 0;
>> +}
>> +
>>   static void
>>   vduse_device_start(struct virtio_net *dev)
>>   {
>> @@ -304,6 +342,23 @@ vduse_device_start(struct virtio_net *dev)
>>   	}
>>   }
>>
>> +static void
>> +vduse_device_stop(struct virtio_net *dev)
>> +{
>> +	unsigned int i;
>> +
>> +	VHOST_LOG_CONFIG(dev->ifname, INFO, "Stopping device...\n");
>> +
>> +	vhost_destroy_device_notify(dev);
>> +
>> +	dev->flags &= ~VIRTIO_DEV_READY;
>> +
>> +	for (i = 0; i < dev->nr_vring; i++)
>> +		vduse_vring_cleanup(dev, i);
>> +
>> +	vhost_user_iotlb_flush_all(dev);
>> +}
>> +
>>   static void
>>   vduse_events_handler(int fd, void *arg, int *remove __rte_unused)
>>   {
>> @@ -311,6 +366,7 @@ vduse_events_handler(int fd, void *arg, int *remove
>> __rte_unused)
>>   	struct vduse_dev_request req;
>>   	struct vduse_dev_response resp;
>>   	struct vhost_virtqueue *vq;
>> +	uint8_t old_status;
>>   	int ret;
>>
>>   	memset(&resp, 0, sizeof(resp));
>> @@ -339,10 +395,15 @@ vduse_events_handler(int fd, void *arg, int *remove
>> __rte_unused)
>>   	case VDUSE_SET_STATUS:
>>   		VHOST_LOG_CONFIG(dev->ifname, INFO, "\tnew status: 0x%08x\n",
>>   				req.s.status);
>> +		old_status = dev->status;
>>   		dev->status = req.s.status;
>>
>> -		if (dev->status & VIRTIO_DEVICE_STATUS_DRIVER_OK)
>> -			vduse_device_start(dev);
>> +		if ((old_status ^ dev->status) &
>> VIRTIO_DEVICE_STATUS_DRIVER_OK) {
>> +			if (dev->status & VIRTIO_DEVICE_STATUS_DRIVER_OK)
>> +				vduse_device_start(dev);
>> +			else
>> +				vduse_device_stop(dev);
>> +		}
>>
>>   		resp.result = VDUSE_REQ_RESULT_OK;
>>   		break;
>> @@ -560,12 +621,7 @@ vduse_device_destroy(const char *path)
>>   	if (vid == RTE_MAX_VHOST_DEVICE)
>>   		return -1;
>>
>> -	if (dev->cvq && dev->cvq->kickfd >= 0) {
>> -		fdset_del(&vduse.fdset, dev->cvq->kickfd);
>> -		fdset_pipe_notify(&vduse.fdset);
>> -		close(dev->cvq->kickfd);
>> -		dev->cvq->kickfd = VIRTIO_UNINITIALIZED_EVENTFD;
>> -	}
>> +	vduse_device_stop(dev);
>>
>>   	fdset_del(&vduse.fdset, dev->vduse_dev_fd);
>>   	fdset_pipe_notify(&vduse.fdset);
>> --
>> 2.40.1
>