Re: [iwl-next v3 05/15] ice: allocate devlink for subfunction

[Michal Swiatkowski <michal.swiatkowski@linux.intel.com>]

On Tue, May 28, 2024 at 09:11:09AM +0200, Przemek Kitszel wrote:
> On 5/28/24 06:38, Michal Swiatkowski wrote:
> > From: Piotr Raczynski <piotr.raczynski@intel.com>
> > 
> > Make devlink allocation function generic to use it for PF and for SF.
> > 
> > Add function for SF devlink port creation. It will be used in next
> > patch.
> > 
> > Create header file for subfunction device. Define subfunction device
> > structure there as it is needed for devlink allocation and port
> > creation.
> > 
> > Signed-off-by: Piotr Raczynski <piotr.raczynski@intel.com>
> > Signed-off-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
> > ---
> >   .../net/ethernet/intel/ice/devlink/devlink.c  | 33 +++++++++++++++
> >   .../net/ethernet/intel/ice/devlink/devlink.h  |  1 +
> >   .../ethernet/intel/ice/devlink/devlink_port.c | 41 +++++++++++++++++++
> >   .../ethernet/intel/ice/devlink/devlink_port.h |  3 ++
> >   drivers/net/ethernet/intel/ice/ice_sf_eth.h   | 21 ++++++++++
> >   5 files changed, 99 insertions(+)
> >   create mode 100644 drivers/net/ethernet/intel/ice/ice_sf_eth.h
> 
> just two minor nitpicks, so:
> Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
> 
> > 
> > diff --git a/drivers/net/ethernet/intel/ice/devlink/devlink.c b/drivers/net/ethernet/intel/ice/devlink/devlink.c
> > index bfb3d5b59a62..58196c170b1b 100644
> > --- a/drivers/net/ethernet/intel/ice/devlink/devlink.c
> > +++ b/drivers/net/ethernet/intel/ice/devlink/devlink.c
> > @@ -10,6 +10,7 @@
> >   #include "ice_eswitch.h"
> >   #include "ice_fw_update.h"
> >   #include "ice_dcb_lib.h"
> > +#include "ice_sf_eth.h"
> >   /* context for devlink info version reporting */
> >   struct ice_info_ctx {
> > @@ -1282,6 +1283,8 @@ static const struct devlink_ops ice_devlink_ops = {
> >   	.port_new = ice_devlink_port_new,
> >   };
> > +static const struct devlink_ops ice_sf_devlink_ops;
> > +
> >   static int
> >   ice_devlink_enable_roce_get(struct devlink *devlink, u32 id,
> >   			    struct devlink_param_gset_ctx *ctx)
> > @@ -1422,6 +1425,7 @@ static void ice_devlink_free(void *devlink_ptr)
> >    * Allocate a devlink instance for this device and return the private area as
> >    * the PF structure. The devlink memory is kept track of through devres by
> >    * adding an action to remove it when unwinding.
> > + *
> >    */
> >   struct ice_pf *ice_allocate_pf(struct device *dev)
> >   {
> > @@ -1438,6 +1442,35 @@ struct ice_pf *ice_allocate_pf(struct device *dev)
> >   	return devlink_priv(devlink);
> >   }
> > +/**
> > + * ice_allocate_sf - Allocate devlink and return SF structure pointer
> > + * @dev: the device to allocate for
> > + * @pf: pointer to the PF structure
> > + *
> > + * Allocate a devlink instance for SF.
> > + *
> > + * Return: void pointer to allocated memory
> 
> nit: it's not void; you could add "or ERR_PTR in case of error"
> 

Right, will fix

> > + */
> > +struct ice_sf_priv *ice_allocate_sf(struct device *dev, struct ice_pf *pf)
> > +{
> > +	struct devlink *devlink;
> > +	int err;
> > +
> > +	devlink = devlink_alloc_ns(&ice_sf_devlink_ops,
> > +				   sizeof(struct ice_sf_priv),
> > +				   devlink_net(priv_to_devlink(pf)), dev);
> > +	if (!devlink)
> > +		return NULL;
> 
> ERR_PTR(-ENOMEM) would be more consistent with the other error exit path
>

Ok

> > +
> > +	err = devl_nested_devlink_set(priv_to_devlink(pf), devlink);
> > +	if (err) {
> > +		devlink_free(devlink);
> > +		return ERR_PTR(err);
> > +	}
> > +
> > +	return devlink_priv(devlink);
> > +}
> > +
> >   /**
> >    * ice_devlink_register - Register devlink interface for this PF
> >    * @pf: the PF to register the devlink for.
> > diff --git a/drivers/net/ethernet/intel/ice/devlink/devlink.h b/drivers/net/ethernet/intel/ice/devlink/devlink.h
> > index d291c0e2e17b..1af3b0763fbb 100644
> > --- a/drivers/net/ethernet/intel/ice/devlink/devlink.h
> > +++ b/drivers/net/ethernet/intel/ice/devlink/devlink.h
> > @@ -5,6 +5,7 @@
> >   #define _ICE_DEVLINK_H_
> >   struct ice_pf *ice_allocate_pf(struct device *dev);
> > +struct ice_sf_priv *ice_allocate_sf(struct device *dev, struct ice_pf *pf);
> >   void ice_devlink_register(struct ice_pf *pf);
> >   void ice_devlink_unregister(struct ice_pf *pf);
> > diff --git a/drivers/net/ethernet/intel/ice/devlink/devlink_port.c b/drivers/net/ethernet/intel/ice/devlink/devlink_port.c
> > index 5d1fe08e4bab..f06baabd0112 100644
> > --- a/drivers/net/ethernet/intel/ice/devlink/devlink_port.c
> > +++ b/drivers/net/ethernet/intel/ice/devlink/devlink_port.c
> > @@ -489,6 +489,47 @@ void ice_devlink_destroy_vf_port(struct ice_vf *vf)
> >   	devl_port_unregister(&vf->devlink_port);
> >   }
> > +/**
> > + * ice_devlink_create_sf_dev_port - Register virtual port for a subfunction
> > + * @sf_dev: the subfunction device to create a devlink port for
> > + *
> > + * Register virtual flavour devlink port for the subfunction auxiliary device
> > + * created after activating a dynamically added devlink port.
> > + *
> > + * Return: zero on success or an error code on failure.
> > + */
> > +int ice_devlink_create_sf_dev_port(struct ice_sf_dev *sf_dev)
> > +{
> > +	struct devlink_port_attrs attrs = {};
> > +	struct ice_dynamic_port *dyn_port;
> > +	struct devlink_port *devlink_port;
> > +	struct devlink *devlink;
> > +	struct ice_vsi *vsi;
> > +
> > +	dyn_port = sf_dev->dyn_port;
> > +	vsi = dyn_port->vsi;
> > +
> > +	devlink_port = &sf_dev->priv->devlink_port;
> > +
> > +	attrs.flavour = DEVLINK_PORT_FLAVOUR_VIRTUAL;
> 
> (just comment, not an issue)
> we have (among others):
> 198│ enum devlink_port_flavour {
> 199│         DEVLINK_PORT_FLAVOUR_PHYSICAL, /* Any kind of a port physically
> 200│                                         * facing the user.
> 201│                                         */
> 210│         DEVLINK_PORT_FLAVOUR_PCI_VF, /* Represents eswitch port
> 211│                                       * for the PCI VF. It is an
> internal
> 212│                                       * port that faces the PCI VF.
> 213│                                       */
> 214│         DEVLINK_PORT_FLAVOUR_VIRTUAL, /* Any virtual port facing the
> user. */
> 216│                                       * is not used in any way.
> 217│                                       */
> 218│         DEVLINK_PORT_FLAVOUR_PCI_SF, /* Represents eswitch port
> 219│                                       * for the PCI SF. It is an
> internal
> 220│                                       * port that faces the PCI SF.
> 221│                                       */
> 
> from that I conclude that _PCI_ ones are internal, and you are adding
> user-facing port, so your choice is good, even if there is one with SF
> in the name. Perhaps the enum should have this piece of documentation ;)
>

DEVLINK_PORT_FLAVOUR_PCI_SF is created during port representor creation
and linked with his netdev.

According to the documentation:
Documentation/networking/devlink/devlink-port.rst

Thanks,
Michal

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