Subject: Re: [PATCH v5 04/22] ice: Register auxiliary device to provide RDMA

From: Leon Romanovsky <[email-masked]>
Date: Wed, 19 May 2021 14:31:03 +0300

On Fri, May 14, 2021 at 09:11:56AM -0500, Shiraz Saleem wrote:
> From: Dave Ertman <[email-masked]>
> 
> Register ice client auxiliary RDMA device on the auxiliary bus per
> PCIe device function for the auxiliary driver (irdma) to attach to.
> It allows to realize a single RDMA driver (irdma) capable of working with
> multiple netdev drivers over multi-generation Intel HW supporting RDMA.
> There is no load ordering dependencies between ice and irdma.
> 
> Signed-off-by: Dave Ertman <[email-masked]>
> Signed-off-by: Tony Nguyen <[email-masked]>
> Signed-off-by: Shiraz Saleem <[email-masked]>
> ---
>  drivers/net/ethernet/intel/Kconfig        |  1 +
>  drivers/net/ethernet/intel/ice/ice.h      |  8 +++-
>  drivers/net/ethernet/intel/ice/ice_idc.c  | 71 ++++++++++++++++++++++++++++++-
>  drivers/net/ethernet/intel/ice/ice_main.c | 11 ++++-
>  4 files changed, 87 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/Kconfig b/drivers/net/ethernet/intel/Kconfig
> index c1d1556..d8a12da 100644
> --- a/drivers/net/ethernet/intel/Kconfig
> +++ b/drivers/net/ethernet/intel/Kconfig
> @@ -294,6 +294,7 @@ config ICE
>  	tristate "Intel(R) Ethernet Connection E800 Series Support"
>  	default n
>  	depends on PCI_MSI
> +	select AUXILIARY_BUS
>  	select DIMLIB
>  	select NET_DEVLINK
>  	select PLDMFW
> diff --git a/drivers/net/ethernet/intel/ice/ice.h b/drivers/net/ethernet/intel/ice/ice.h
> index 225f8a5..228055e 100644
> --- a/drivers/net/ethernet/intel/ice/ice.h
> +++ b/drivers/net/ethernet/intel/ice/ice.h
> @@ -34,6 +34,7 @@
>  #include <linux/if_bridge.h>
>  #include <linux/ctype.h>
>  #include <linux/bpf.h>
> +#include <linux/auxiliary_bus.h>
>  #include <linux/avf/virtchnl.h>
>  #include <linux/cpu_rmap.h>
>  #include <linux/dim.h>
> @@ -647,6 +648,8 @@ static inline void ice_clear_sriov_cap(struct ice_pf *pf)
>  void ice_fill_rss_lut(u8 *lut, u16 rss_table_size, u16 rss_size);
>  int ice_schedule_reset(struct ice_pf *pf, enum ice_reset_req reset);
>  void ice_print_link_msg(struct ice_vsi *vsi, bool isup);
> +int ice_plug_aux_dev(struct ice_pf *pf);
> +void ice_unplug_aux_dev(struct ice_pf *pf);
>  int ice_init_rdma(struct ice_pf *pf);
>  const char *ice_stat_str(enum ice_status stat_err);
>  const char *ice_aq_str(enum ice_aq_err aq_err);
> @@ -678,8 +681,10 @@ int ice_aq_wait_for_event(struct ice_pf *pf, u16 opcode, unsigned long timeout,
>   */
>  static inline void ice_set_rdma_cap(struct ice_pf *pf)
>  {
> -	if (pf->hw.func_caps.common_cap.rdma && pf->num_rdma_msix)
> +	if (pf->hw.func_caps.common_cap.rdma && pf->num_rdma_msix) {
>  		set_bit(ICE_FLAG_RDMA_ENA, pf->flags);
> +		ice_plug_aux_dev(pf);
> +	}
>  }
>  
>  /**
> @@ -688,6 +693,7 @@ static inline void ice_set_rdma_cap(struct ice_pf *pf)
>   */
>  static inline void ice_clear_rdma_cap(struct ice_pf *pf)
>  {
> +	ice_unplug_aux_dev(pf);
>  	clear_bit(ICE_FLAG_RDMA_ENA, pf->flags);
>  }
>  #endif /* _ICE_H_ */
> diff --git a/drivers/net/ethernet/intel/ice/ice_idc.c b/drivers/net/ethernet/intel/ice/ice_idc.c
> index ffca0d5..e7bb8f6 100644
> --- a/drivers/net/ethernet/intel/ice/ice_idc.c
> +++ b/drivers/net/ethernet/intel/ice/ice_idc.c
> @@ -255,6 +255,71 @@ static int ice_reserve_rdma_qvector(struct ice_pf *pf)
>  }
>  
>  /**
> + * ice_adev_release - function to be mapped to AUX dev's release op
> + * @dev: pointer to device to free
> + */
> +static void ice_adev_release(struct device *dev)
> +{
> +	struct iidc_auxiliary_dev *iadev;
> +
> +	iadev = container_of(dev, struct iidc_auxiliary_dev, adev.dev);
> +	kfree(iadev);
> +}
> +
> +/**
> + * ice_plug_aux_dev - allocate and register AUX device
> + * @pf: pointer to pf struct
> + */
> +int ice_plug_aux_dev(struct ice_pf *pf)
> +{
> +	struct iidc_auxiliary_dev *iadev;
> +	struct auxiliary_device *adev;
> +	int ret;
> +
> +	iadev = kzalloc(sizeof(*iadev), GFP_KERNEL);
> +	if (!iadev)
> +		return -ENOMEM;
> +
> +	adev = &iadev->adev;
> +	pf->adev = adev;
> +	iadev->pf = pf;
> +
> +	adev->id = pf->aux_idx;
> +	adev->dev.release = ice_adev_release;
> +	adev->dev.parent = &pf->pdev->dev;
> +	adev->name = IIDC_RDMA_ROCE_NAME;

You declared IIDC_RDMA_ROCE_NAME as intel_rdma_roce, so it will create
extremely awful device name, something like irdma.intel_rdma_roce.0

I would say that "intel" and "rdma" can be probably dropped.

Thanks