diff mbox series

[net-next,v2,2/3] rtnetlink: add IFLA_PARENT_[DEV|DEV_BUS]_NAME

Message ID 1623347089-28788-2-git-send-email-loic.poulain@linaro.org
State New
Headers show
Series [net-next,v2,1/3] rtnetlink: add alloc() method to rtnl_link_ops | expand

Commit Message

Loic Poulain June 10, 2021, 5:44 p.m. UTC
From: Johannes Berg <johannes.berg@intel.com>


In some cases, for example in the upcoming WWAN framework changes,
there's no natural "parent netdev", so sometimes dummy netdevs are
created or similar. IFLA_PARENT_DEV_NAME is a new attribute intended to
contain a device (sysfs, struct device) name that can be used instead
when creating a new netdev, if the rtnetlink family implements it.

As suggested by Parav Pandit, we also introduce IFLA_PARENT_DEV_BUS_NAME
attribute in order to uniquely identify a device on the system (with
bus/name pair).

ip-link(8) support for the generic parent device attributes will help
us avoid code duplication, so no other link type will require a custom
code to handle the parent name attribute. E.g. the WWAN interface
creation command will looks like this:

$ ip link add wwan0-1 parent-dev wwan0 type wwan channel-id 1

So, some future subsystem (or driver) FOO will have an interface
creation command that looks like this:

$ ip link add foo1-3 parent-dev foo1 type foo bar-id 3 baz-type Y

Below is an example of dumping link info of a random device with these
new attributes:

$ ip --details link show wlp0s20f3
  4: wlp0s20f3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue
     state UP mode DORMANT group default qlen 1000
     ...
     parent_devname 0000:00:14.3 parent_busname pci

Co-developed-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>

Co-developed-by: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>

Suggested-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

---
 v2: - Squashed Johannes and Sergey changes
     - Added IFLA_PARENT_DEV_BUS_NAME attribute
     - reworded commit message + introduce Sergey's comment

 include/uapi/linux/if_link.h |  7 +++++++
 net/core/rtnetlink.c         | 12 ++++++++++++
 2 files changed, 19 insertions(+)

-- 
2.7.4

Comments

Parav Pandit June 11, 2021, 1:01 p.m. UTC | #1
> From: Loic Poulain <loic.poulain@linaro.org>

> Sent: Thursday, June 10, 2021 11:15 PM

> 

> From: Johannes Berg <johannes.berg@intel.com>

> 

> In some cases, for example in the upcoming WWAN framework changes,

> there's no natural "parent netdev", so sometimes dummy netdevs are

> created or similar. IFLA_PARENT_DEV_NAME is a new attribute intended to

> contain a device (sysfs, struct device) name that can be used instead when

> creating a new netdev, if the rtnetlink family implements it.

> 

> As suggested by Parav Pandit, we also introduce

> IFLA_PARENT_DEV_BUS_NAME attribute in order to uniquely identify a

> device on the system (with bus/name pair).

> 

> ip-link(8) support for the generic parent device attributes will help us avoid

> code duplication, so no other link type will require a custom code to handle

> the parent name attribute. E.g. the WWAN interface creation command will

> looks like this:

> 

> $ ip link add wwan0-1 parent-dev wwan0 type wwan channel-id 1

> 

> So, some future subsystem (or driver) FOO will have an interface creation

> command that looks like this:

> 

> $ ip link add foo1-3 parent-dev foo1 type foo bar-id 3 baz-type Y

> 

> Below is an example of dumping link info of a random device with these new

> attributes:

> 

> $ ip --details link show wlp0s20f3

>   4: wlp0s20f3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc

> noqueue

>      state UP mode DORMANT group default qlen 1000

>      ...

>      parent_devname 0000:00:14.3 parent_busname pci


Showing bus first followed device is more preferred approach to see hierarchy.
Please change their sequence.

You should drop "name" suffix.
"parent_bus" and "parent_dev" are just fine.

> 

> Co-developed-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>

> Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>

> Co-developed-by: Loic Poulain <loic.poulain@linaro.org>

> Signed-off-by: Loic Poulain <loic.poulain@linaro.org>

> Suggested-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>

> Signed-off-by: Johannes Berg <johannes.berg@intel.com>

> ---

>  v2: - Squashed Johannes and Sergey changes

>      - Added IFLA_PARENT_DEV_BUS_NAME attribute

>      - reworded commit message + introduce Sergey's comment

> 

>  include/uapi/linux/if_link.h |  7 +++++++

>  net/core/rtnetlink.c         | 12 ++++++++++++

>  2 files changed, 19 insertions(+)

> 

> diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index

> a5a7f0e..4882e81 100644

> --- a/include/uapi/linux/if_link.h

> +++ b/include/uapi/linux/if_link.h

> @@ -341,6 +341,13 @@ enum {

>  	IFLA_ALT_IFNAME, /* Alternative ifname */

>  	IFLA_PERM_ADDRESS,

>  	IFLA_PROTO_DOWN_REASON,

> +

> +	/* device (sysfs) name as parent, used instead

> +	 * of IFLA_LINK where there's no parent netdev

> +	 */

> +	IFLA_PARENT_DEV_NAME,

> +	IFLA_PARENT_DEV_BUS_NAME,

> +

>  	__IFLA_MAX

>  };

> 

> diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 92c3e43..32599f3

> 100644

> --- a/net/core/rtnetlink.c

> +++ b/net/core/rtnetlink.c

> @@ -1821,6 +1821,16 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb,

>  	if (rtnl_fill_prop_list(skb, dev))

>  		goto nla_put_failure;

> 

> +	if (dev->dev.parent &&

> +	    nla_put_string(skb, IFLA_PARENT_DEV_NAME,

> +			   dev_name(dev->dev.parent)))

> +		goto nla_put_failure;

> +

> +	if (dev->dev.parent && dev->dev.parent->bus &&

> +	    nla_put_string(skb, IFLA_PARENT_DEV_BUS_NAME,

> +			   dev->dev.parent->bus->name))

> +		goto nla_put_failure;

> +

>  	nlmsg_end(skb, nlh);

>  	return 0;

> 

> @@ -1880,6 +1890,8 @@ static const struct nla_policy

> ifla_policy[IFLA_MAX+1] = {

>  	[IFLA_PERM_ADDRESS]	= { .type = NLA_REJECT },

>  	[IFLA_PROTO_DOWN_REASON] = { .type = NLA_NESTED },

>  	[IFLA_NEW_IFINDEX]	= NLA_POLICY_MIN(NLA_S32, 1),

> +	[IFLA_PARENT_DEV_NAME]	= { .type = NLA_NUL_STRING },

> +	[IFLA_PARENT_DEV_BUS_NAME] = { .type = NLA_NUL_STRING },

>  };

> 

This hunk should go in the patch that enables users to use these fields to specify it for new link creation.
Loic Poulain June 11, 2021, 3:07 p.m. UTC | #2
Hi Parav,

On Fri, 11 Jun 2021 at 15:01, Parav Pandit <parav@nvidia.com> wrote:
>

>

>

> > From: Loic Poulain <loic.poulain@linaro.org>

> > Sent: Thursday, June 10, 2021 11:15 PM

> >

> > From: Johannes Berg <johannes.berg@intel.com>

> >

> > In some cases, for example in the upcoming WWAN framework changes,

> > there's no natural "parent netdev", so sometimes dummy netdevs are

> > created or similar. IFLA_PARENT_DEV_NAME is a new attribute intended to

> > contain a device (sysfs, struct device) name that can be used instead when

> > creating a new netdev, if the rtnetlink family implements it.

> >

> > As suggested by Parav Pandit, we also introduce

> > IFLA_PARENT_DEV_BUS_NAME attribute in order to uniquely identify a

> > device on the system (with bus/name pair).

> >

> > ip-link(8) support for the generic parent device attributes will help us avoid

> > code duplication, so no other link type will require a custom code to handle

> > the parent name attribute. E.g. the WWAN interface creation command will

> > looks like this:

> >

> > $ ip link add wwan0-1 parent-dev wwan0 type wwan channel-id 1

> >

> > So, some future subsystem (or driver) FOO will have an interface creation

> > command that looks like this:

> >

> > $ ip link add foo1-3 parent-dev foo1 type foo bar-id 3 baz-type Y

> >

> > Below is an example of dumping link info of a random device with these new

> > attributes:

> >

> > $ ip --details link show wlp0s20f3

> >   4: wlp0s20f3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc

> > noqueue

> >      state UP mode DORMANT group default qlen 1000

> >      ...

> >      parent_devname 0000:00:14.3 parent_busname pci

>

> Showing bus first followed device is more preferred approach to see hierarchy.

> Please change their sequence.

>

> You should drop "name" suffix.

> "parent_bus" and "parent_dev" are just fine.


Do you think it can also be dropped for the IFLA symbol
(IFLA_PARENT_DEV && IFLA_PARENT_BUS_NAME).

>

> >

> > Co-developed-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>

> > Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>

> > Co-developed-by: Loic Poulain <loic.poulain@linaro.org>

> > Signed-off-by: Loic Poulain <loic.poulain@linaro.org>

> > Suggested-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>

> > Signed-off-by: Johannes Berg <johannes.berg@intel.com>

> > ---

> >  v2: - Squashed Johannes and Sergey changes

> >      - Added IFLA_PARENT_DEV_BUS_NAME attribute

> >      - reworded commit message + introduce Sergey's comment

> >

> >  include/uapi/linux/if_link.h |  7 +++++++

> >  net/core/rtnetlink.c         | 12 ++++++++++++

> >  2 files changed, 19 insertions(+)

> >

> > diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index

> > a5a7f0e..4882e81 100644

> > --- a/include/uapi/linux/if_link.h

> > +++ b/include/uapi/linux/if_link.h

> > @@ -341,6 +341,13 @@ enum {

> >       IFLA_ALT_IFNAME, /* Alternative ifname */

> >       IFLA_PERM_ADDRESS,

> >       IFLA_PROTO_DOWN_REASON,

> > +

> > +     /* device (sysfs) name as parent, used instead

> > +      * of IFLA_LINK where there's no parent netdev

> > +      */

> > +     IFLA_PARENT_DEV_NAME,

> > +     IFLA_PARENT_DEV_BUS_NAME,

> > +

> >       __IFLA_MAX

> >  };

> >

> > diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 92c3e43..32599f3

> > 100644

> > --- a/net/core/rtnetlink.c

> > +++ b/net/core/rtnetlink.c

> > @@ -1821,6 +1821,16 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb,

> >       if (rtnl_fill_prop_list(skb, dev))

> >               goto nla_put_failure;

> >

> > +     if (dev->dev.parent &&

> > +         nla_put_string(skb, IFLA_PARENT_DEV_NAME,

> > +                        dev_name(dev->dev.parent)))

> > +             goto nla_put_failure;

> > +

> > +     if (dev->dev.parent && dev->dev.parent->bus &&

> > +         nla_put_string(skb, IFLA_PARENT_DEV_BUS_NAME,

> > +                        dev->dev.parent->bus->name))

> > +             goto nla_put_failure;

> > +

> >       nlmsg_end(skb, nlh);

> >       return 0;

> >

> > @@ -1880,6 +1890,8 @@ static const struct nla_policy

> > ifla_policy[IFLA_MAX+1] = {

> >       [IFLA_PERM_ADDRESS]     = { .type = NLA_REJECT },

> >       [IFLA_PROTO_DOWN_REASON] = { .type = NLA_NESTED },

> >       [IFLA_NEW_IFINDEX]      = NLA_POLICY_MIN(NLA_S32, 1),

> > +     [IFLA_PARENT_DEV_NAME]  = { .type = NLA_NUL_STRING },

> > +     [IFLA_PARENT_DEV_BUS_NAME] = { .type = NLA_NUL_STRING },

> >  };

> >

> This hunk should go in the patch that enables users to use these fields to specify it for new link creation.


ack.

Thx,
Loic
Parav Pandit June 11, 2021, 3:43 p.m. UTC | #3
> From: Loic Poulain <loic.poulain@linaro.org>

> Sent: Friday, June 11, 2021 8:37 PM

> 

> Hi Parav,

> 

> On Fri, 11 Jun 2021 at 15:01, Parav Pandit <parav@nvidia.com> wrote:

> >

> >

> >

> > > From: Loic Poulain <loic.poulain@linaro.org>

> > > Sent: Thursday, June 10, 2021 11:15 PM

> > >

> > > From: Johannes Berg <johannes.berg@intel.com>

> > >

> > > In some cases, for example in the upcoming WWAN framework changes,

> > > there's no natural "parent netdev", so sometimes dummy netdevs are

> > > created or similar. IFLA_PARENT_DEV_NAME is a new attribute intended

> > > to contain a device (sysfs, struct device) name that can be used

> > > instead when creating a new netdev, if the rtnetlink family implements it.

> > >

> > > As suggested by Parav Pandit, we also introduce

> > > IFLA_PARENT_DEV_BUS_NAME attribute in order to uniquely identify a

> > > device on the system (with bus/name pair).

> > >

> > > ip-link(8) support for the generic parent device attributes will

> > > help us avoid code duplication, so no other link type will require a

> > > custom code to handle the parent name attribute. E.g. the WWAN

> > > interface creation command will looks like this:

> > >

> > > $ ip link add wwan0-1 parent-dev wwan0 type wwan channel-id 1

> > >

> > > So, some future subsystem (or driver) FOO will have an interface

> > > creation command that looks like this:

> > >

> > > $ ip link add foo1-3 parent-dev foo1 type foo bar-id 3 baz-type Y

> > >

> > > Below is an example of dumping link info of a random device with

> > > these new

> > > attributes:

> > >

> > > $ ip --details link show wlp0s20f3

> > >   4: wlp0s20f3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc

> > > noqueue

> > >      state UP mode DORMANT group default qlen 1000

> > >      ...

> > >      parent_devname 0000:00:14.3 parent_busname pci

> >

> > Showing bus first followed device is more preferred approach to see

> hierarchy.

> > Please change their sequence.

> >

> > You should drop "name" suffix.

> > "parent_bus" and "parent_dev" are just fine.

> 

> Do you think it can also be dropped for the IFLA symbol (IFLA_PARENT_DEV

> && IFLA_PARENT_BUS_NAME).

IFLA symbol with _NAME is fine as it covers what the field is.
Loic Poulain June 11, 2021, 3:46 p.m. UTC | #4
Hi Parav,

On Fri, 11 Jun 2021 at 15:01, Parav Pandit <parav@nvidia.com> wrote:
>

>

>

> > From: Loic Poulain <loic.poulain@linaro.org>

> > Sent: Thursday, June 10, 2021 11:15 PM

> >

> > From: Johannes Berg <johannes.berg@intel.com>

> >

> > In some cases, for example in the upcoming WWAN framework changes,

> > there's no natural "parent netdev", so sometimes dummy netdevs are

> > created or similar. IFLA_PARENT_DEV_NAME is a new attribute intended to

> > contain a device (sysfs, struct device) name that can be used instead when

> > creating a new netdev, if the rtnetlink family implements it.

> >

> > As suggested by Parav Pandit, we also introduce

> > IFLA_PARENT_DEV_BUS_NAME attribute in order to uniquely identify a

> > device on the system (with bus/name pair).


[...]

> > diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index

> > a5a7f0e..4882e81 100644

> > --- a/include/uapi/linux/if_link.h

> > +++ b/include/uapi/linux/if_link.h

> > @@ -341,6 +341,13 @@ enum {

> >       IFLA_ALT_IFNAME, /* Alternative ifname */

> >       IFLA_PERM_ADDRESS,

> >       IFLA_PROTO_DOWN_REASON,

> > +

> > +     /* device (sysfs) name as parent, used instead

> > +      * of IFLA_LINK where there's no parent netdev

> > +      */

> > +     IFLA_PARENT_DEV_NAME,

> > +     IFLA_PARENT_DEV_BUS_NAME,

> > +

> >       __IFLA_MAX

> >  };

> >

> > diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 92c3e43..32599f3

> > 100644

> > --- a/net/core/rtnetlink.c

> > +++ b/net/core/rtnetlink.c

> > @@ -1821,6 +1821,16 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb,

> >       if (rtnl_fill_prop_list(skb, dev))

> >               goto nla_put_failure;

> >

> > +     if (dev->dev.parent &&

> > +         nla_put_string(skb, IFLA_PARENT_DEV_NAME,

> > +                        dev_name(dev->dev.parent)))

> > +             goto nla_put_failure;

> > +

> > +     if (dev->dev.parent && dev->dev.parent->bus &&

> > +         nla_put_string(skb, IFLA_PARENT_DEV_BUS_NAME,

> > +                        dev->dev.parent->bus->name))

> > +             goto nla_put_failure;

> > +

> >       nlmsg_end(skb, nlh);

> >       return 0;

> >

> > @@ -1880,6 +1890,8 @@ static const struct nla_policy

> > ifla_policy[IFLA_MAX+1] = {

> >       [IFLA_PERM_ADDRESS]     = { .type = NLA_REJECT },

> >       [IFLA_PROTO_DOWN_REASON] = { .type = NLA_NESTED },

> >       [IFLA_NEW_IFINDEX]      = NLA_POLICY_MIN(NLA_S32, 1),

> > +     [IFLA_PARENT_DEV_NAME]  = { .type = NLA_NUL_STRING },

> > +     [IFLA_PARENT_DEV_BUS_NAME] = { .type = NLA_NUL_STRING },

> >  };

> >

> This hunk should go in the patch that enables users to use these fields to specify it for new link creation.


Don't get it, the previous changes I see in the tree change both
if_link.h and rtnetlink.c for new atributes (e.g. f74877a5457d). Can
you elaborate on what you expect here?

Thanks,
Loic
Parav Pandit June 11, 2021, 4 p.m. UTC | #5
> From: Loic Poulain <loic.poulain@linaro.org>

> Sent: Friday, June 11, 2021 9:16 PM

> 

> Hi Parav,

> 

> On Fri, 11 Jun 2021 at 15:01, Parav Pandit <parav@nvidia.com> wrote:

> >

> >

> >

> > > From: Loic Poulain <loic.poulain@linaro.org>

> > > Sent: Thursday, June 10, 2021 11:15 PM

> > >

> > > From: Johannes Berg <johannes.berg@intel.com>

> > >

> > > In some cases, for example in the upcoming WWAN framework changes,

> > > there's no natural "parent netdev", so sometimes dummy netdevs are

> > > created or similar. IFLA_PARENT_DEV_NAME is a new attribute intended

> > > to contain a device (sysfs, struct device) name that can be used

> > > instead when creating a new netdev, if the rtnetlink family implements it.

> > >

> > > As suggested by Parav Pandit, we also introduce

> > > IFLA_PARENT_DEV_BUS_NAME attribute in order to uniquely identify a

> > > device on the system (with bus/name pair).

> 

> [...]

> 

> > > diff --git a/include/uapi/linux/if_link.h

> > > b/include/uapi/linux/if_link.h index

> > > a5a7f0e..4882e81 100644

> > > --- a/include/uapi/linux/if_link.h

> > > +++ b/include/uapi/linux/if_link.h

> > > @@ -341,6 +341,13 @@ enum {

> > >       IFLA_ALT_IFNAME, /* Alternative ifname */

> > >       IFLA_PERM_ADDRESS,

> > >       IFLA_PROTO_DOWN_REASON,

> > > +

> > > +     /* device (sysfs) name as parent, used instead

> > > +      * of IFLA_LINK where there's no parent netdev

> > > +      */

> > > +     IFLA_PARENT_DEV_NAME,

> > > +     IFLA_PARENT_DEV_BUS_NAME,

> > > +

> > >       __IFLA_MAX

> > >  };

> > >

> > > diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index

> > > 92c3e43..32599f3

> > > 100644

> > > --- a/net/core/rtnetlink.c

> > > +++ b/net/core/rtnetlink.c

> > > @@ -1821,6 +1821,16 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb,

> > >       if (rtnl_fill_prop_list(skb, dev))

> > >               goto nla_put_failure;

> > >

> > > +     if (dev->dev.parent &&

> > > +         nla_put_string(skb, IFLA_PARENT_DEV_NAME,

> > > +                        dev_name(dev->dev.parent)))

> > > +             goto nla_put_failure;

> > > +

> > > +     if (dev->dev.parent && dev->dev.parent->bus &&

> > > +         nla_put_string(skb, IFLA_PARENT_DEV_BUS_NAME,

> > > +                        dev->dev.parent->bus->name))

> > > +             goto nla_put_failure;

> > > +

> > >       nlmsg_end(skb, nlh);

> > >       return 0;

> > >

> > > @@ -1880,6 +1890,8 @@ static const struct nla_policy

> > > ifla_policy[IFLA_MAX+1] = {

> > >       [IFLA_PERM_ADDRESS]     = { .type = NLA_REJECT },

> > >       [IFLA_PROTO_DOWN_REASON] = { .type = NLA_NESTED },

> > >       [IFLA_NEW_IFINDEX]      = NLA_POLICY_MIN(NLA_S32, 1),

> > > +     [IFLA_PARENT_DEV_NAME]  = { .type = NLA_NUL_STRING },

> > > +     [IFLA_PARENT_DEV_BUS_NAME] = { .type = NLA_NUL_STRING },

> > >  };

> > >

> > This hunk should go in the patch that enables users to use these fields to

> specify it for new link creation.

> 

> Don't get it, the previous changes I see in the tree change both if_link.h and

> rtnetlink.c for new atributes (e.g. f74877a5457d). Can you elaborate on what

> you expect here?

> 

Commit f74877a5457d did in same patch because one of the objective of commit f74877a5457d is to also block PERM_ADDR using policy NLA_REJECT.
This patch-2 is not enabling user to pass these params via new_link command.
It is done in a later patch. So ifla_policy doesn’t need to have these fields in this patch.
Loic Poulain June 11, 2021, 4:12 p.m. UTC | #6
On Fri, 11 Jun 2021 at 18:00, Parav Pandit <parav@nvidia.com> wrote:
>

>

>

> > From: Loic Poulain <loic.poulain@linaro.org>

> > Sent: Friday, June 11, 2021 9:16 PM

> >

> > Hi Parav,

> >

> > On Fri, 11 Jun 2021 at 15:01, Parav Pandit <parav@nvidia.com> wrote:

> > >

> > >

> > >

> > > > From: Loic Poulain <loic.poulain@linaro.org>

> > > > Sent: Thursday, June 10, 2021 11:15 PM

> > > >

> > > > From: Johannes Berg <johannes.berg@intel.com>

> > > >

> > > > In some cases, for example in the upcoming WWAN framework changes,

> > > > there's no natural "parent netdev", so sometimes dummy netdevs are

> > > > created or similar. IFLA_PARENT_DEV_NAME is a new attribute intended

> > > > to contain a device (sysfs, struct device) name that can be used

> > > > instead when creating a new netdev, if the rtnetlink family implements it.

> > > >

> > > > As suggested by Parav Pandit, we also introduce

> > > > IFLA_PARENT_DEV_BUS_NAME attribute in order to uniquely identify a

> > > > device on the system (with bus/name pair).

> >

> > [...]

> >

> > > > diff --git a/include/uapi/linux/if_link.h

> > > > b/include/uapi/linux/if_link.h index

> > > > a5a7f0e..4882e81 100644

> > > > --- a/include/uapi/linux/if_link.h

> > > > +++ b/include/uapi/linux/if_link.h

> > > > @@ -341,6 +341,13 @@ enum {

> > > >       IFLA_ALT_IFNAME, /* Alternative ifname */

> > > >       IFLA_PERM_ADDRESS,

> > > >       IFLA_PROTO_DOWN_REASON,

> > > > +

> > > > +     /* device (sysfs) name as parent, used instead

> > > > +      * of IFLA_LINK where there's no parent netdev

> > > > +      */

> > > > +     IFLA_PARENT_DEV_NAME,

> > > > +     IFLA_PARENT_DEV_BUS_NAME,

> > > > +

> > > >       __IFLA_MAX

> > > >  };

> > > >

> > > > diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index

> > > > 92c3e43..32599f3

> > > > 100644

> > > > --- a/net/core/rtnetlink.c

> > > > +++ b/net/core/rtnetlink.c

> > > > @@ -1821,6 +1821,16 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb,

> > > >       if (rtnl_fill_prop_list(skb, dev))

> > > >               goto nla_put_failure;

> > > >

> > > > +     if (dev->dev.parent &&

> > > > +         nla_put_string(skb, IFLA_PARENT_DEV_NAME,

> > > > +                        dev_name(dev->dev.parent)))

> > > > +             goto nla_put_failure;

> > > > +

> > > > +     if (dev->dev.parent && dev->dev.parent->bus &&

> > > > +         nla_put_string(skb, IFLA_PARENT_DEV_BUS_NAME,

> > > > +                        dev->dev.parent->bus->name))

> > > > +             goto nla_put_failure;

> > > > +

> > > >       nlmsg_end(skb, nlh);

> > > >       return 0;

> > > >

> > > > @@ -1880,6 +1890,8 @@ static const struct nla_policy

> > > > ifla_policy[IFLA_MAX+1] = {

> > > >       [IFLA_PERM_ADDRESS]     = { .type = NLA_REJECT },

> > > >       [IFLA_PROTO_DOWN_REASON] = { .type = NLA_NESTED },

> > > >       [IFLA_NEW_IFINDEX]      = NLA_POLICY_MIN(NLA_S32, 1),

> > > > +     [IFLA_PARENT_DEV_NAME]  = { .type = NLA_NUL_STRING },

> > > > +     [IFLA_PARENT_DEV_BUS_NAME] = { .type = NLA_NUL_STRING },

> > > >  };

> > > >

> > > This hunk should go in the patch that enables users to use these fields to

> > specify it for new link creation.

> >

> > Don't get it, the previous changes I see in the tree change both if_link.h and

> > rtnetlink.c for new atributes (e.g. f74877a5457d). Can you elaborate on what

> > you expect here?

> >

> Commit f74877a5457d did in same patch because one of the objective of commit f74877a5457d is to also block PERM_ADDR using policy NLA_REJECT.

> This patch-2 is not enabling user to pass these params via new_link command.

> It is done in a later patch. So ifla_policy doesn’t need to have these fields in this patch.


Understood, thanks.
Loic
diff mbox series

Patch

diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index a5a7f0e..4882e81 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -341,6 +341,13 @@  enum {
 	IFLA_ALT_IFNAME, /* Alternative ifname */
 	IFLA_PERM_ADDRESS,
 	IFLA_PROTO_DOWN_REASON,
+
+	/* device (sysfs) name as parent, used instead
+	 * of IFLA_LINK where there's no parent netdev
+	 */
+	IFLA_PARENT_DEV_NAME,
+	IFLA_PARENT_DEV_BUS_NAME,
+
 	__IFLA_MAX
 };
 
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 92c3e43..32599f3 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1821,6 +1821,16 @@  static int rtnl_fill_ifinfo(struct sk_buff *skb,
 	if (rtnl_fill_prop_list(skb, dev))
 		goto nla_put_failure;
 
+	if (dev->dev.parent &&
+	    nla_put_string(skb, IFLA_PARENT_DEV_NAME,
+			   dev_name(dev->dev.parent)))
+		goto nla_put_failure;
+
+	if (dev->dev.parent && dev->dev.parent->bus &&
+	    nla_put_string(skb, IFLA_PARENT_DEV_BUS_NAME,
+			   dev->dev.parent->bus->name))
+		goto nla_put_failure;
+
 	nlmsg_end(skb, nlh);
 	return 0;
 
@@ -1880,6 +1890,8 @@  static const struct nla_policy ifla_policy[IFLA_MAX+1] = {
 	[IFLA_PERM_ADDRESS]	= { .type = NLA_REJECT },
 	[IFLA_PROTO_DOWN_REASON] = { .type = NLA_NESTED },
 	[IFLA_NEW_IFINDEX]	= NLA_POLICY_MIN(NLA_S32, 1),
+	[IFLA_PARENT_DEV_NAME]	= { .type = NLA_NUL_STRING },
+	[IFLA_PARENT_DEV_BUS_NAME] = { .type = NLA_NUL_STRING },
 };
 
 static const struct nla_policy ifla_info_policy[IFLA_INFO_MAX+1] = {