Re: [dpdk-dev] [PATCH v2] vhost: add config change slave msg support

[Tiwei Bie <tiwei.bie@intel.com>]

On Thu, Dec 05, 2019 at 12:01:55PM +0800, Li Feng wrote:
> Tiwei Bie <tiwei.bie@intel.com> 于2019年12月5日周四 上午10:06写道：
> > On Wed, Dec 04, 2019 at 05:43:50PM +0800, Li Feng wrote:
> > > Hi Tiwei,
> > > Thanks for your reply.
> > > Yes, this new API currently is for vhost-user-blk in the SPDK project.
> >
> > I see. Thanks for the clarification.
> > In this case, it should be declared in rte_vhost.h instead
> > of vhost_user.h which is an internal header. And the symbol
> > should be added to rte_vhost_version.map as well.
> >
> OK,  one more question, should I add `__rte_experimental` tag before
> the declare?

Yeah.

> 
> > >
> > > There is a patch in SPDK to use this API.
> >
> > Could you share the link to the SPDK patch?
> >
> The patch is here:
> https://review.gerrithub.io/c/spdk/spdk/+/476704

Thanks for the link. Will take a closer look.

Thanks,
Tiwei

> 
> Thanks.
> Feng Li
> 
> > Thanks,
> > Tiwei
> >
> > >
> > > Thanks,
> > >
> > > Feng Li
> > >
> > > Tiwei Bie <tiwei.bie@intel.com> 于2019年12月4日周三 下午5:30写道：
> > > >
> > > > On Wed, Dec 04, 2019 at 01:13:20PM +0800, Li Feng wrote:
> > > > > This msg is used to notify qemu that should get the config of backend.
> > > > >
> > > > > For example, vhost-user-blk uses this msg to notify guest os the
> > > > > compacity of backend has changed.
> > > > >
> > > > > Signed-off-by: Li Feng <fengli@smartx.com>
> > > > > ---
> > > > > v2:
> > > > > * Fix a little log typo.
> > > > >
> > > > >  lib/librte_vhost/vhost_user.c | 31 +++++++++++++++++++++++++++++++
> > > > >  lib/librte_vhost/vhost_user.h |  2 ++
> > > > >  2 files changed, 33 insertions(+)
> > > > >
> > > > > diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
> > > > > index 0cfb8b792..10f2e47d5 100644
> > > > > --- a/lib/librte_vhost/vhost_user.c
> > > > > +++ b/lib/librte_vhost/vhost_user.c
> > > > > @@ -2840,6 +2840,37 @@ vhost_user_iotlb_miss(struct virtio_net *dev, uint64_t iova, uint8_t perm)
> > > > >       return 0;
> > > > >  }
> > > > >
> > > > > +static int
> > > > > +vhost_user_slave_config_change(struct virtio_net *dev)
> > > > > +{
> > > > > +     int ret;
> > > > > +     struct VhostUserMsg msg = {
> > > > > +             .request.slave = VHOST_USER_SLAVE_CONFIG_CHANGE_MSG,
> > > > > +             .flags = VHOST_USER_VERSION,
> > > > > +             .size = 0,
> > > > > +     };
> > > > > +
> > > > > +     ret = send_vhost_message(dev->slave_req_fd, &msg);
> > > > > +     if (ret < 0) {
> > > > > +             RTE_LOG(ERR, VHOST_CONFIG,
> > > > > +                             "Failed to send config change (%d)\n",
> > > > > +                             ret);
> > > > > +             return ret;
> > > > > +     }
> > > > > +
> > > > > +     return 0;
> > > > > +}
> > > > > +
> > > > > +int
> > > > > +rte_vhost_user_slave_config_change(int vid)
> > > > > +{
> > > > > +     struct virtio_net *dev;
> > > > > +     dev = get_device(vid);
> > > > > +     if (!dev)
> > > > > +             return -ENODEV;
> > > > > +     return vhost_user_slave_config_change(dev);
> > > > > +}
> > > > > +
> > > > >  static int vhost_user_slave_set_vring_host_notifier(struct virtio_net *dev,
> > > > >                                                   int index, int fd,
> > > > >                                                   uint64_t offset,
> > > > > diff --git a/lib/librte_vhost/vhost_user.h b/lib/librte_vhost/vhost_user.h
> > > > > index 6563f7315..5c1bb2138 100644
> > > > > --- a/lib/librte_vhost/vhost_user.h
> > > > > +++ b/lib/librte_vhost/vhost_user.h
> > > > > @@ -62,6 +62,7 @@ typedef enum VhostUserRequest {
> > > > >  typedef enum VhostUserSlaveRequest {
> > > > >       VHOST_USER_SLAVE_NONE = 0,
> > > > >       VHOST_USER_SLAVE_IOTLB_MSG = 1,
> > > > > +     VHOST_USER_SLAVE_CONFIG_CHANGE_MSG = 2,
> > > > >       VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG = 3,
> > > > >       VHOST_USER_SLAVE_MAX
> > > > >  } VhostUserSlaveRequest;
> > > > > @@ -158,6 +159,7 @@ typedef struct VhostUserMsg {
> > > > >  /* vhost_user.c */
> > > > >  int vhost_user_msg_handler(int vid, int fd);
> > > > >  int vhost_user_iotlb_miss(struct virtio_net *dev, uint64_t iova, uint8_t perm);
> > > > > +int rte_vhost_user_slave_config_change(int vid);
> > > >
> > > > This is supposed to be an API for external backends?
> > > >
> > > > Thanks,
> > > > Tiwei
> > > >
> > > > >
> > > > >  /* socket.c */
> > > > >  int read_fd_message(int sockfd, char *buf, int buflen, int *fds, int max_fds,
> > > > > --
> > > > > 2.11.0
> > > > >
> > > > >
> > > > > --
> > > > > The SmartX email address is only for business purpose. Any sent message
> > > > > that is not related to the business is not authorized or permitted by
> > > > > SmartX.
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> > > > >
> > > > >
> > >
> > > --
> > > The SmartX email address is only for business purpose. Any sent message
> > > that is not related to the business is not authorized or permitted by
> > > SmartX.
> > > 本邮箱为北京志凌海纳科技有限公司（SmartX）工作邮箱. 如本邮箱发出的邮件与工作无关,该邮件未得到本公司任何的明示或默示的授权.
> > >
> > >
> 
> -- 
> The SmartX email address is only for business purpose. Any sent message 
> that is not related to the business is not authorized or permitted by 
> SmartX.
> 本邮箱为北京志凌海纳科技有限公司（SmartX）工作邮箱. 如本邮箱发出的邮件与工作无关,该邮件未得到本公司任何的明示或默示的授权.
> 
>