On 12/23/20 6:37 AM, Xia, Chenbo wrote:
> Hi Maxime,
>
>> -----Original Message-----
>> From: Maxime Coquelin <maxime.coque...@redhat.com>
>> Sent: Tuesday, December 22, 2020 6:56 PM
>> To: Xia, Chenbo <chenbo....@intel.com>; dev@dpdk.org; amore...@redhat.com;
>> jasow...@redhat.com; david.march...@redhat.com
>> Cc: sta...@dpdk.org
>> Subject: Re: [PATCH 21.02 v2 1/2] net/virtio: fix missing backend features
>> negotiation
>>
>>
>>
>> On 12/21/20 7:23 AM, Xia, Chenbo wrote:
>>> Hi Maxime,
>>>
>>>> -----Original Message-----
>>>> From: Maxime Coquelin <maxime.coque...@redhat.com>
>>>> Sent: Wednesday, November 25, 2020 11:21 PM
>>>> To: dev@dpdk.org; Xia, Chenbo <chenbo....@intel.com>; amore...@redhat.com;
>>>> jasow...@redhat.com; david.march...@redhat.com
>>>> Cc: Maxime Coquelin <maxime.coque...@redhat.com>; sta...@dpdk.org
>>>> Subject: [PATCH 21.02 v2 1/2] net/virtio: fix missing backend features
>>>> negotiation
>>>>
>>>> This patch adds missing backend features negotiation for
>>>> in Vhost-vDPA. Without it, IOTLB messages v2 could be sent
>>>> by Virtio-user PMD while not supported by the backend.
>>>>
>>>> Fixes: 6b901437056e ("net/virtio: introduce vhost-vDPA backend")
>>>> Cc: sta...@dpdk.org
>>>>
>>>> Signed-off-by: Maxime Coquelin <maxime.coque...@redhat.com>
>>>> ---
>>>> drivers/net/virtio/virtio_user/vhost.h | 4 ++++
>>>> drivers/net/virtio/virtio_user/vhost_vdpa.c | 14 ++++++++++++++
>>>> drivers/net/virtio/virtio_user/virtio_user_dev.c | 14 ++++++++++----
>>>> 3 files changed, 28 insertions(+), 4 deletions(-)
>>>>
>>>> diff --git a/drivers/net/virtio/virtio_user/vhost.h
>>>> b/drivers/net/virtio/virtio_user/vhost.h
>>>> index 210a3704e7..c1dcc50b58 100644
>>>> --- a/drivers/net/virtio/virtio_user/vhost.h
>>>> +++ b/drivers/net/virtio/virtio_user/vhost.h
>>>> @@ -86,6 +86,10 @@ enum vhost_user_request {
>>>> VHOST_USER_MAX
>>>> };
>>>>
>>>> +#ifndef VHOST_BACKEND_F_IOTLB_MSG_V2
>>>> +#define VHOST_BACKEND_F_IOTLB_MSG_V2 1
>>>> +#endif
>>>> +
>>>> extern const char * const vhost_msg_strings[VHOST_USER_MAX];
>>>>
>>>> struct vhost_memory_region {
>>>> diff --git a/drivers/net/virtio/virtio_user/vhost_vdpa.c
>>>> b/drivers/net/virtio/virtio_user/vhost_vdpa.c
>>>> index c7b9349fc8..b6c81d6f17 100644
>>>> --- a/drivers/net/virtio/virtio_user/vhost_vdpa.c
>>>> +++ b/drivers/net/virtio/virtio_user/vhost_vdpa.c
>>>> @@ -35,6 +35,8 @@
>>>> #define VHOST_VDPA_SET_STATUS _IOW(VHOST_VIRTIO, 0x72, __u8)
>>>> #define VHOST_VDPA_SET_VRING_ENABLE _IOW(VHOST_VIRTIO, 0x75, \
>>>> struct vhost_vring_state)
>>>> +#define VHOST_SET_BACKEND_FEATURES _IOW(VHOST_VIRTIO, 0x25, __u64)
>>>> +#define VHOST_GET_BACKEND_FEATURES _IOR(VHOST_VIRTIO, 0x26, __u64)
>>>>
>>>> static uint64_t vhost_req_user_to_vdpa[] = {
>>>> [VHOST_USER_SET_OWNER] = VHOST_SET_OWNER,
>>>> @@ -51,6 +53,8 @@ static uint64_t vhost_req_user_to_vdpa[] = {
>>>> [VHOST_USER_SET_STATUS] = VHOST_VDPA_SET_STATUS,
>>>> [VHOST_USER_GET_STATUS] = VHOST_VDPA_GET_STATUS,
>>>> [VHOST_USER_SET_VRING_ENABLE] = VHOST_VDPA_SET_VRING_ENABLE,
>>>> + [VHOST_USER_GET_PROTOCOL_FEATURES] = VHOST_GET_BACKEND_FEATURES,
>>>> + [VHOST_USER_SET_PROTOCOL_FEATURES] = VHOST_SET_BACKEND_FEATURES,
>>>> };
>>>>
>>>> /* no alignment requirement */
>>>> @@ -86,6 +90,11 @@ vhost_vdpa_dma_map(struct virtio_user_dev *dev, void
>> *addr,
>>>> {
>>>> struct vhost_msg msg = {};
>>>>
>>>> + if (!(dev->protocol_features & (1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2)))
>>>> {
>>>> + PMD_DRV_LOG(ERR, "IOTLB_MSG_V2 not supported by the backend.");
>>>> + return -1;
>>>> + }
>>>> +
>>>> msg.type = VHOST_IOTLB_MSG_V2;
>>>> msg.iotlb.type = VHOST_IOTLB_UPDATE;
>>>> msg.iotlb.iova = iova;
>>>> @@ -108,6 +117,11 @@ vhost_vdpa_dma_unmap(struct virtio_user_dev *dev,
>>>> __rte_unused void *addr,
>>>> {
>>>> struct vhost_msg msg = {};
>>>>
>>>> + if (!(dev->protocol_features & (1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2)))
>>>> {
>>>> + PMD_DRV_LOG(ERR, "IOTLB_MSG_V2 not supported by the backend.");
>>>> + return -1;
>>>> + }
>>>> +
>>>> msg.type = VHOST_IOTLB_MSG_V2;
>>>> msg.iotlb.type = VHOST_IOTLB_INVALIDATE;
>>>> msg.iotlb.iova = iova;
>>>> diff --git a/drivers/net/virtio/virtio_user/virtio_user_dev.c
>>>> b/drivers/net/virtio/virtio_user/virtio_user_dev.c
>>>> index 053f0267ca..96bc6b232d 100644
>>>> --- a/drivers/net/virtio/virtio_user/virtio_user_dev.c
>>>> +++ b/drivers/net/virtio/virtio_user/virtio_user_dev.c
>>>> @@ -439,11 +439,13 @@ virtio_user_dev_setup(struct virtio_user_dev *dev)
>>>> 1ULL << VIRTIO_F_RING_PACKED | \
>>>> 1ULL << VHOST_USER_F_PROTOCOL_FEATURES)
>>>>
>>>> -#define VIRTIO_USER_SUPPORTED_PROTOCOL_FEATURES \
>>>> +#define VHOST_USER_SUPPORTED_PROTOCOL_FEATURES \
>>>> (1ULL << VHOST_USER_PROTOCOL_F_MQ | \
>>>> 1ULL << VHOST_USER_PROTOCOL_F_REPLY_ACK | \
>>>> 1ULL << VHOST_USER_PROTOCOL_F_STATUS)
>>>>
>>>> +#define VHOST_VDPA_SUPPORTED_PROTOCOL_FEATURES \
>>>> + (1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2)
>>>> int
>>>> virtio_user_dev_init(struct virtio_user_dev *dev, char *path, int queues,
>>>> int cq, int queue_size, const char *mac, char **ifname,
>>>> @@ -462,9 +464,13 @@ virtio_user_dev_init(struct virtio_user_dev *dev, char
>>>> *path, int queues,
>>>> dev->mac_specified = 0;
>>>> dev->frontend_features = 0;
>>>> dev->unsupported_features = ~VIRTIO_USER_SUPPORTED_FEATURES;
>>>> - dev->protocol_features = VIRTIO_USER_SUPPORTED_PROTOCOL_FEATURES;
>>>> dev->backend_type = backend_type;
>>>>
>>>> + if (dev->backend_type == VIRTIO_USER_BACKEND_VHOST_USER)
>>>> + dev->protocol_features = VHOST_USER_SUPPORTED_PROTOCOL_FEATURES;
>>>> + else if (dev->backend_type == VIRTIO_USER_BACKEND_VHOST_VDPA)
>>>> + dev->protocol_features = VHOST_VDPA_SUPPORTED_PROTOCOL_FEATURES;
>>>> +
>>>> parse_mac(dev, mac);
>>>>
>>>> if (*ifname) {
>>>> @@ -497,8 +503,8 @@ virtio_user_dev_init(struct virtio_user_dev *dev, char
>>>> *path, int queues,
>>>> }
>>>>
>>>>
>>>> - if (dev->device_features &
>>>> - (1ULL << VHOST_USER_F_PROTOCOL_FEATURES)) {
>>>> + if ((dev->device_features & (1ULL <<
>>>> VHOST_USER_F_PROTOCOL_FEATURES) ||
>>>> + dev->backend_type ==
>>>> VIRTIO_USER_BACKEND_VHOST_VDPA))
>>>
>>> Do you mean:
>>>
>>> if ((dev->device_features & (1ULL << VHOST_USER_F_PROTOCOL_FEATURES)) ||
>>> (dev->backend_type ==
>>> VIRTIO_USER_BACKEND_VHOST_VDPA))
>> {
>>>
>>> here?
>>
>> Indeed!
>>
>>> Besides, I think it's better to update here as vhost-vdpa also uses
>> protocol_features.
>>>
>> (http://code.dpdk.org/dpdk/v20.08/source/drivers/net/virtio/virtio_user/virtio
>> _user_dev.h#L44)
>>
>> Not sure what you mean here? Can you please elaborate?
>
> Sorry, I'm not clear on this. It's just a small point about code comment.
>
> In
> http://code.dpdk.org/dpdk/v20.11/source/drivers/net/virtio/virtio_user/virtio_user_dev.h#L52,
> It says 'negotiated protocol features(vhost-user only)'. Since it's also used
> by vhost-vdpa now,
> maybe it's better to improve it. What do you think?
I think it makes sense!
Note that in my Virtio PMD rework series, this field disappears, meaning
that once this series applied, I will need to rebase my rework on top of
it so that vhost-vdpa backend features is moved into vhost_vdpa.c.
In the mean time, I will remove the "(vhost-user only)" comment.
Thanks,
Maxime
> Thanks!
> Chenbo
>
>>
>> Thanks!
>> Maxime
>>
>>> Thanks!
>>> Chenbo
>>>
>>>> {
>>>> if (dev->ops->send_request(dev,
>>>> VHOST_USER_GET_PROTOCOL_FEATURES,
>>>> &protocol_features))
>>>> --
>>>> 2.26.2
>>>
>
