net_pkt: Extend packet abstraction as required by e1000e functionality

This patch extends the TX/RX packet abstractions with features that will
be used by the e1000e device implementation.

Changes are:

  1. Support iovec lists for RX buffers
  2. Deeper RX packets parsing
  3. Loopback option for TX packets
  4. Extended VLAN headers handling
  5. RSS processing for RX packets

Signed-off-by: Dmitry Fleytman <dmitry.fleytman@ravellosystems.com>
Signed-off-by: Leonid Bloch <leonid.bloch@ravellosystems.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>

Author: Dmitry Fleytman

hw/net/net_rx_pkt.c

@@ -77,6 +77,103 @@ void net_rx_pkt_get_protocols(struct NetRxPkt *pkt,
                                  bool *isip4, bool *isip6,
                                  bool *isudp, bool *istcp);
 
+/**
+* fetches L3 header offset
+*
+* @pkt:            packet
+*
+*/
+size_t net_rx_pkt_get_l3_hdr_offset(struct NetRxPkt *pkt);
+
+/**
+* fetches L4 header offset
+*
+* @pkt:            packet
+*
+*/
+size_t net_rx_pkt_get_l4_hdr_offset(struct NetRxPkt *pkt);
+
+/**
+* fetches L5 header offset
+*
+* @pkt:            packet
+*
+*/
+size_t net_rx_pkt_get_l5_hdr_offset(struct NetRxPkt *pkt);
+
+/**
+ * fetches IP6 header analysis results
+ *
+ * Return:  pointer to analysis results structure which is stored in internal
+ *          packet area.
+ *
+ */
+eth_ip6_hdr_info *net_rx_pkt_get_ip6_info(struct NetRxPkt *pkt);
+
+/**
+ * fetches IP4 header analysis results
+ *
+ * Return:  pointer to analysis results structure which is stored in internal
+ *          packet area.
+ *
+ */
+eth_ip4_hdr_info *net_rx_pkt_get_ip4_info(struct NetRxPkt *pkt);
+
+/**
+ * fetches L4 header analysis results
+ *
+ * Return:  pointer to analysis results structure which is stored in internal
+ *          packet area.
+ *
+ */
+eth_l4_hdr_info *net_rx_pkt_get_l4_info(struct NetRxPkt *pkt);
+
+typedef enum {
+    NetPktRssIpV4,
+    NetPktRssIpV4Tcp,
+    NetPktRssIpV6Tcp,
+    NetPktRssIpV6,
+    NetPktRssIpV6Ex
+} NetRxPktRssType;
+
+/**
+* calculates RSS hash for packet
+*
+* @pkt:            packet
+* @type:           RSS hash type
+*
+* Return:  Toeplitz RSS hash.
+*
+*/
+uint32_t
+net_rx_pkt_calc_rss_hash(struct NetRxPkt *pkt,
+                         NetRxPktRssType type,
+                         uint8_t *key);
+
+/**
+* fetches IP identification for the packet
+*
+* @pkt:            packet
+*
+*/
+uint16_t net_rx_pkt_get_ip_id(struct NetRxPkt *pkt);
+
+/**
+* check if given packet is a TCP ACK packet
+*
+* @pkt:            packet
+*
+*/
+bool net_rx_pkt_is_tcp_ack(struct NetRxPkt *pkt);
+
+/**
+* check if given packet contains TCP data
+*
+* @pkt:            packet
+*
+*/
+bool net_rx_pkt_has_tcp_data(struct NetRxPkt *pkt);
+
 /**
  * returns virtio header stored in rx context
  *
@@ -122,6 +219,37 @@ bool net_rx_pkt_is_vlan_stripped(struct NetRxPkt *pkt);
  */
 bool net_rx_pkt_has_virt_hdr(struct NetRxPkt *pkt);
 
+/**
+* attach scatter-gather data to rx packet
+*
+* @pkt:            packet
+* @iov:            received data scatter-gather list
+* @iovcnt          number of elements in iov
+* @iovoff          data start offset in the iov
+* @strip_vlan:     should the module strip vlan from data
+*
+*/
+void net_rx_pkt_attach_iovec(struct NetRxPkt *pkt,
+                                const struct iovec *iov,
+                                int iovcnt, size_t iovoff,
+                                bool strip_vlan);
+
+/**
+* attach scatter-gather data to rx packet
+*
+* @pkt:            packet
+* @iov:            received data scatter-gather list
+* @iovcnt          number of elements in iov
+* @iovoff          data start offset in the iov
+* @strip_vlan:     should the module strip vlan from data
+* @vet:            VLAN tag Ethernet type
+*
+*/
+void net_rx_pkt_attach_iovec_ex(struct NetRxPkt *pkt,
+                                   const struct iovec *iov, int iovcnt,
+                                   size_t iovoff, bool strip_vlan,
+                                   uint16_t vet);
+
 /**
  * attach data to rx packet
  *
@@ -131,8 +259,17 @@ bool net_rx_pkt_has_virt_hdr(struct NetRxPkt *pkt);
  * @strip_vlan:     should the module strip vlan from data
  *
  */
-void net_rx_pkt_attach_data(struct NetRxPkt *pkt, const void *data,
-    size_t len, bool strip_vlan);
+static inline void
+net_rx_pkt_attach_data(struct NetRxPkt *pkt, const void *data,
+                          size_t len, bool strip_vlan)
+{
+    const struct iovec iov = {
+        .iov_base = (void *) data,
+        .iov_len = len
+    };
+
+    net_rx_pkt_attach_iovec(pkt, &iov, 1, 0, strip_vlan);
+}
 
 /**
  * returns io vector that holds the attached data
@@ -143,6 +280,15 @@ void net_rx_pkt_attach_data(struct NetRxPkt *pkt, const void *data,
  */
 struct iovec *net_rx_pkt_get_iovec(struct NetRxPkt *pkt);
 
+/**
+* returns io vector length that holds the attached data
+*
+* @pkt:            packet
+* @ret:            IOVec length
+*
+*/
+uint16_t net_rx_pkt_get_iovec_len(struct NetRxPkt *pkt);
+
 /**
  * prints rx packet data if debug is enabled
  *
@@ -161,6 +307,17 @@ void net_rx_pkt_dump(struct NetRxPkt *pkt);
 void net_rx_pkt_set_vhdr(struct NetRxPkt *pkt,
     struct virtio_net_hdr *vhdr);
 
+/**
+* copy passed vhdr data to packet context
+*
+* @pkt:            packet
+* @iov:            VHDR iov
+* @iovcnt:         VHDR iov array size
+*
+*/
+void net_rx_pkt_set_vhdr_iovec(struct NetRxPkt *pkt,
+    const struct iovec *iov, int iovcnt);
+
 /**
  * save packet type in packet context
  *
@@ -171,4 +328,36 @@ void net_rx_pkt_set_vhdr(struct NetRxPkt *pkt,
 void net_rx_pkt_set_packet_type(struct NetRxPkt *pkt,
     eth_pkt_types_e packet_type);
 
+/**
+* validate TCP/UDP checksum of the packet
+*
+* @pkt:            packet
+* @csum_valid:     checksum validation result
+* @ret:            true if validation was performed, false in case packet is
+*                  not TCP/UDP or checksum validation is not possible
+*
+*/
+bool net_rx_pkt_validate_l4_csum(struct NetRxPkt *pkt, bool *csum_valid);
+
+/**
+* validate IPv4 checksum of the packet
+*
+* @pkt:            packet
+* @csum_valid:     checksum validation result
+* @ret:            true if validation was performed, false in case packet is
+*                  not TCP/UDP or checksum validation is not possible
+*
+*/
+bool net_rx_pkt_validate_l3_csum(struct NetRxPkt *pkt, bool *csum_valid);
+
+/**
+* fix IPv4 checksum of the packet
+*
+* @pkt:            packet
+* @ret:            true if checksum was fixed, false in case packet is
+*                  not TCP/UDP or checksum correction is not possible
+*
+*/
+bool net_rx_pkt_fix_l4_csum(struct NetRxPkt *pkt);
+
 #endif