Re: [PATCH 03/11] netdev: add XDP_SETUP_ZC_RX command

[David Wei <dw@davidwei.uk>]

On 25/08/2023 19:21, David Ahern wrote:
> On 8/25/23 6:19 PM, David Wei wrote:
>> diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
>> index 08fbd4622ccf..a20a5c847916 100644
>> --- a/include/linux/netdevice.h
>> +++ b/include/linux/netdevice.h
>> @@ -1000,6 +1000,7 @@ enum bpf_netdev_command {
>>  	BPF_OFFLOAD_MAP_ALLOC,
>>  	BPF_OFFLOAD_MAP_FREE,
>>  	XDP_SETUP_XSK_POOL,
>> +	XDP_SETUP_ZC_RX,
> 
> Why XDP in the name? Packets go from nic to driver to stack to io_uring,
> no? That is not XDP.

This new bpf_netdev_command XDP_SETUP_ZC_RX mirrors XDP_SETUP_XSK_POOL above,
both in terms of naming and purpose (the arg structs are almost identical).

However, I dislike this way of toggling ZC RX support anyway and am happy to
change it to a better method e.g. properly supports namespaces.

> 
> 
>>  };
>>  
>>  struct bpf_prog_offload_ops;
>> @@ -1038,6 +1039,11 @@ struct netdev_bpf {
>>  			struct xsk_buff_pool *pool;
>>  			u16 queue_id;
>>  		} xsk;
>> +		/* XDP_SETUP_ZC_RX */
>> +		struct {
>> +			struct io_zc_rx_ifq *ifq;
>> +			u16 queue_id;
>> +		} zc_rx;
>>  	};
>>  };
>>  
>