RE: [PATCH net-next v14 07/13] rtase: Implement a function to receive packets

[JustinLai0215 <justinlai0215@realtek.com>]

> On Fri, 2023-12-08 at 17:47 +0800, Justin Lai wrote:
> > Implement rx_handler to read the information of the rx descriptor,
> > thereby checking the packet accordingly and storing the packet in the
> > socket buffer to complete the reception of the packet.
> >
> > Signed-off-by: Justin Lai <justinlai0215@realtek.com>
> > ---
> >  .../net/ethernet/realtek/rtase/rtase_main.c   | 148 ++++++++++++++++++
> >  1 file changed, 148 insertions(+)
> >
> > diff --git a/drivers/net/ethernet/realtek/rtase/rtase_main.c
> > b/drivers/net/ethernet/realtek/rtase/rtase_main.c
> > index eee792ea4760..83a119389110 100644
> > --- a/drivers/net/ethernet/realtek/rtase/rtase_main.c
> > +++ b/drivers/net/ethernet/realtek/rtase/rtase_main.c
> > @@ -451,6 +451,154 @@ static void rtase_rx_ring_clear(struct rtase_ring
> *ring)
> >       }
> >  }
> >
> > +static int rtase_fragmented_frame(u32 status) {
> > +     return (status & (RX_FIRST_FRAG | RX_LAST_FRAG)) !=
> > +             (RX_FIRST_FRAG | RX_LAST_FRAG); }
> > +
> > +static void rtase_rx_csum(const struct rtase_private *tp, struct sk_buff
> *skb,
> > +                       const union rx_desc *desc) {
> > +     u32 opts2 = le32_to_cpu(desc->desc_status.opts2);
> > +
> > +     /* rx csum offload */
> > +     if (((opts2 & RX_V4F) && !(opts2 & RX_IPF)) || (opts2 & RX_V6F)) {
> > +             if (((opts2 & RX_TCPT) && !(opts2 & RX_TCPF)) ||
> > +                 ((opts2 & RX_UDPT) && !(opts2 & RX_UDPF))) {
> > +                     skb->ip_summed = CHECKSUM_UNNECESSARY;
> > +             } else {
> > +                     skb->ip_summed = CHECKSUM_NONE;
> > +             }
> > +     } else {
> > +             skb->ip_summed = CHECKSUM_NONE;
> > +     }
> > +}
> > +
> > +static void rtase_rx_vlan_skb(union rx_desc *desc, struct sk_buff
> > +*skb) {
> > +     u32 opts2 = le32_to_cpu(desc->desc_status.opts2);
> > +
> > +     if (!(opts2 & RX_VLAN_TAG))
> > +             return;
> > +
> > +     __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), swab16(opts2 &
> > +VLAN_TAG_MASK)); }
> > +
> > +static void rtase_rx_skb(const struct rtase_ring *ring, struct
> > +sk_buff *skb) {
> > +     struct rtase_int_vector *ivec = ring->ivec;
> > +
> > +     napi_gro_receive(&ivec->napi, skb); }
> > +
> > +static int rx_handler(struct rtase_ring *ring, int budget) {
> > +     const struct rtase_private *tp = ring->ivec->tp;
> > +     u32 pkt_size, cur_rx, delta, entry, status;
> > +     union rx_desc *desc_base = ring->desc;
> > +     struct net_device *dev = tp->dev;
> > +     struct sk_buff *skb;
> > +     union rx_desc *desc;
> > +     int workdone = 0;
> > +
> > +     if (!ring->desc)
> > +             return workdone;
> 
> Why is the above test required? How can be ring->desc NULL here?

This is unnecessary judgment and I will remove it.
>