treewide: Standardise variable names for various packet lengths

At various points we need to track the lengths of a packet including or
excluding various different sets of headers.  We don't always use the same
variable names for doing so.  Worse in some places we use the same name
for different things: e.g. tcp_fill_headers[46]() use ip_len for the
length including the IP headers, but then tcp_send_flag() which calls it
uses it to mean the IP payload length only.

To improve clarity, standardise on these names:
   dlen:		L4 protocol payload length ("data length")
   l4len:		plen + length of L4 protocol header
   l3len:		l4len + length of IPv4/IPv6 header
   l2len:		l3len + length of L2 (ethernet) header

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

1 files changed, 6 insertions, 6 deletions

diff --git a/checksum.h b/checksum.h
index 0f39676..c5964ac 100644
--- a/checksum.h
+++ b/checksum.h
@@ -13,23 +13,23 @@ struct icmp6hdr;
 uint32_t sum_16b(const void *buf, size_t len);
 uint16_t csum_fold(uint32_t sum);
 uint16_t csum_unaligned(const void *buf, size_t len, uint32_t init);
-uint16_t csum_ip4_header(uint16_t tot_len, uint8_t protocol,
+uint16_t csum_ip4_header(uint16_t l3len, uint8_t protocol,
 			 struct in_addr saddr, struct in_addr daddr);
-uint32_t proto_ipv4_header_psum(uint16_t tot_len, uint8_t protocol,
+uint32_t proto_ipv4_header_psum(uint16_t l4len, uint8_t protocol,
 				struct in_addr saddr, struct in_addr daddr);
 void csum_udp4(struct udphdr *udp4hr,
 	       struct in_addr saddr, struct in_addr daddr,
-	       const void *payload, size_t len);
-void csum_icmp4(struct icmphdr *icmp4hr, const void *payload, size_t len);
+	       const void *payload, size_t dlen);
+void csum_icmp4(struct icmphdr *icmp4hr, const void *payload, size_t dlen);
 uint32_t proto_ipv6_header_psum(uint16_t payload_len, uint8_t protocol,
 				const struct in6_addr *saddr,
 				const struct in6_addr *daddr);
 void csum_udp6(struct udphdr *udp6hr,
 	       const struct in6_addr *saddr, const struct in6_addr *daddr,
-	       const void *payload, size_t len);
+	       const void *payload, size_t dlen);
 void csum_icmp6(struct icmp6hdr *icmp6hr,
 		const struct in6_addr *saddr, const struct in6_addr *daddr,
-		const void *payload, size_t len);
+		const void *payload, size_t dlen);
 uint32_t csum_unfolded(const void *buf, size_t len, uint32_t init);
 uint16_t csum(const void *buf, size_t len, uint32_t init);
 uint16_t csum_iov(const struct iovec *iov, size_t n, uint32_t init);