[dpdk-dev,net-next,v2] hyper-v: allow access to vmbus from userspace driver

  This is enables the hyper-v driver for DPDK <dev@dpdk.org>.
The hv_uio driver needs to access the shared vmbus monitor
pages.

I would also like to put hv_uio in upstream kernel like other
uio drivers, but need to get API accepted with DPDK first.

Signed-off-by: Stas Egorov <segorov@mirantis.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>

---
v2 - simplify and rename to vmbus_get_monitor_pages

 drivers/hv/connection.c |   20 +++++++++++++++++---
 include/linux/hyperv.h  |    3 +++
 2 files changed, 20 insertions(+), 3 deletions(-)
  

Stephen Hemminger <stephen@networkplumber.org> writes:

> This is enables the hyper-v driver for DPDK <dev@dpdk.org>.
> The hv_uio driver needs to access the shared vmbus monitor
> pages.

Why can't we just make vmbus_connection struct public?

>
> I would also like to put hv_uio in upstream kernel like other
> uio drivers, but need to get API accepted with DPDK first.
>
> Signed-off-by: Stas Egorov <segorov@mirantis.com>
> Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
>
> ---
> v2 - simplify and rename to vmbus_get_monitor_pages
>
>  drivers/hv/connection.c |   20 +++++++++++++++++---
>  include/linux/hyperv.h  |    3 +++
>  2 files changed, 20 insertions(+), 3 deletions(-)
>
> --- a/drivers/hv/connection.c	2015-02-03 10:58:51.751752450 -0800
> +++ b/drivers/hv/connection.c	2015-02-04 14:59:51.636194383 -0800
> @@ -64,6 +64,15 @@ static __u32 vmbus_get_next_version(__u3
>  	}
>  }
>
> +void vmbus_get_monitor_pages(unsigned long *int_page,
> +			     unsigned long monitor_pages[2])
> +{

Too weird to be a public interface in my opinion.

> +	*int_page = (unsigned long)vmbus_connection.int_page;
> +	monitor_pages[0] = (unsigned long)vmbus_connection.monitor_pages[0];
> +	monitor_pages[1] = (unsigned long)vmbus_connection.monitor_pages[1];
> +}
> +EXPORT_SYMBOL_GPL(vmbus_get_monitor_pages);
> +
>  static int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo,
>  					__u32 version)
>  {
> @@ -347,10 +356,7 @@ static void process_chn_event(u32 relid)
>  			else
>  				bytes_to_read = 0;
>  		} while (read_state && (bytes_to_read != 0));
> -	} else {
> -		pr_err("no channel callback for relid - %u\n", relid);
>  	}
> -
>  }

This change wasn't mentioned in your commit msg.

>
>  /*
> --- a/include/linux/hyperv.h	2015-02-03 10:58:51.751752450 -0800
> +++ b/include/linux/hyperv.h	2015-02-04 15:00:26.388355012 -0800
> @@ -868,6 +868,9 @@ extern int vmbus_recvpacket_raw(struct v
>
>  extern void vmbus_ontimer(unsigned long data);
>
> +extern void vmbus_get_monitor_pages(unsigned long *int_page,
> +				    unsigned long monitor_pages[2]);
> +
>  /* Base driver object */
>  struct hv_driver {
>  	const char *name;
> _______________________________________________
> devel mailing list
> devel@linuxdriverproject.org
> http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
  

On Thu, 05 Feb 2015 12:01:03 +0100
Vitaly Kuznetsov <vkuznets@redhat.com> wrote:

> Stephen Hemminger <stephen@networkplumber.org> writes:
> 
> > This is enables the hyper-v driver for DPDK <dev@dpdk.org>.
> > The hv_uio driver needs to access the shared vmbus monitor
> > pages.
> 
> Why can't we just make vmbus_connection struct public?
> 
> >
> > I would also like to put hv_uio in upstream kernel like other
> > uio drivers, but need to get API accepted with DPDK first.
> >
> > Signed-off-by: Stas Egorov <segorov@mirantis.com>
> > Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
> >
> > ---
> > v2 - simplify and rename to vmbus_get_monitor_pages
> >
> >  drivers/hv/connection.c |   20 +++++++++++++++++---
> >  include/linux/hyperv.h  |    3 +++
> >  2 files changed, 20 insertions(+), 3 deletions(-)
> >
> > --- a/drivers/hv/connection.c	2015-02-03 10:58:51.751752450 -0800
> > +++ b/drivers/hv/connection.c	2015-02-04 14:59:51.636194383 -0800
> > @@ -64,6 +64,15 @@ static __u32 vmbus_get_next_version(__u3
> >  	}
> >  }
> >
> > +void vmbus_get_monitor_pages(unsigned long *int_page,
> > +			     unsigned long monitor_pages[2])
> > +{
> 
> Too weird to be a public interface in my opinion.
> 
> > +	*int_page = (unsigned long)vmbus_connection.int_page;
> > +	monitor_pages[0] = (unsigned long)vmbus_connection.monitor_pages[0];
> > +	monitor_pages[1] = (unsigned long)vmbus_connection.monitor_pages[1];
> > +}
> > +EXPORT_SYMBOL_GPL(vmbus_get_monitor_pages);
> > +
> >  static int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo,
> >  					__u32 version)
> >  {
> > @@ -347,10 +356,7 @@ static void process_chn_event(u32 relid)
> >  			else
> >  				bytes_to_read = 0;
> >  		} while (read_state && (bytes_to_read != 0));
> > -	} else {
> > -		pr_err("no channel callback for relid - %u\n", relid);
> >  	}
> > -
> >  }
> 
> This change wasn't mentioned in your commit msg.

Was in earlier commit. Need to prevent driver from logging error
when device is not claimed directly by existing kernel devices.