tcp: remove dead code after CHECKSUM_PARTIAL adoption

Since all skbs in write/rtx queues have CHECKSUM_PARTIAL,
we can remove dead code.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index f3e52bc..2c6aec2 100644 (file)
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -561,16 +561,9 @@ void __tcp_v4_send_check(struct sk_buff *skb, __be32 saddr, __be32 daddr)
 {
        struct tcphdr *th = tcp_hdr(skb);
 
-       if (skb->ip_summed == CHECKSUM_PARTIAL) {
-               th->check = ~tcp_v4_check(skb->len, saddr, daddr, 0);
-               skb->csum_start = skb_transport_header(skb) - skb->head;
-               skb->csum_offset = offsetof(struct tcphdr, check);
-       } else {
-               th->check = tcp_v4_check(skb->len, saddr, daddr,
-                                        csum_partial(th,
-                                                     th->doff << 2,
-                                                     skb->csum));
-       }
+       th->check = ~tcp_v4_check(skb->len, saddr, daddr, 0);
+       skb->csum_start = skb_transport_header(skb) - skb->head;
+       skb->csum_offset = offsetof(struct tcphdr, check);
 }
 
 /* This routine computes an IPv4 TCP checksum. */

diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 0196923..8795d76 100644 (file)
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -1335,21 +1335,9 @@ int tcp_fragment(struct sock *sk, enum tcp_queue tcp_queue,
        TCP_SKB_CB(buff)->sacked = TCP_SKB_CB(skb)->sacked;
        tcp_skb_fragment_eor(skb, buff);
 
-       if (!skb_shinfo(skb)->nr_frags && skb->ip_summed != CHECKSUM_PARTIAL) {
-               /* Copy and checksum data tail into the new buffer. */
-               buff->csum = csum_partial_copy_nocheck(skb->data + len,
-                                                      skb_put(buff, nsize),
-                                                      nsize, 0);
-
-               skb_trim(skb, len);
-
-               skb->csum = csum_block_sub(skb->csum, buff->csum, len);
-       } else {
-               skb->ip_summed = CHECKSUM_PARTIAL;
-               skb_split(skb, buff, len);
-       }
+       skb_split(skb, buff, len);
 
-       buff->ip_summed = skb->ip_summed;
+       buff->ip_summed = CHECKSUM_PARTIAL;
 
        buff->tstamp = skb->tstamp;
        tcp_fragment_tstamp(skb, buff);
@@ -1901,7 +1889,7 @@ static int tso_fragment(struct sock *sk, enum tcp_queue tcp_queue,
 
        tcp_skb_fragment_eor(skb, buff);
 
-       buff->ip_summed = skb->ip_summed = CHECKSUM_PARTIAL;
+       buff->ip_summed = CHECKSUM_PARTIAL;
        skb_split(skb, buff, len);
        tcp_fragment_tstamp(skb, buff);
 
@@ -2134,7 +2122,7 @@ static int tcp_mtu_probe(struct sock *sk)
        TCP_SKB_CB(nskb)->tcp_flags = TCPHDR_ACK;
        TCP_SKB_CB(nskb)->sacked = 0;
        nskb->csum = 0;
-       nskb->ip_summed = skb->ip_summed;
+       nskb->ip_summed = CHECKSUM_PARTIAL;
 
        tcp_insert_write_queue_before(nskb, skb, sk);
        tcp_highest_sack_replace(sk, skb, nskb);
@@ -2142,14 +2130,7 @@ static int tcp_mtu_probe(struct sock *sk)
        len = 0;
        tcp_for_write_queue_from_safe(skb, next, sk) {
                copy = min_t(int, skb->len, probe_size - len);
-               if (nskb->ip_summed) {
-                       skb_copy_bits(skb, 0, skb_put(nskb, copy), copy);
-               } else {
-                       __wsum csum = skb_copy_and_csum_bits(skb, 0,
-                                                            skb_put(nskb, copy),
-                                                            copy, 0);
-                       nskb->csum = csum_block_add(nskb->csum, csum, len);
-               }
+               skb_copy_bits(skb, 0, skb_put(nskb, copy), copy);
 
                if (skb->len <= copy) {
                        /* We've eaten all the data from this skb.
@@ -2166,9 +2147,6 @@ static int tcp_mtu_probe(struct sock *sk)
                                                   ~(TCPHDR_FIN|TCPHDR_PSH);
                        if (!skb_shinfo(skb)->nr_frags) {
                                skb_pull(skb, copy);
-                               if (skb->ip_summed != CHECKSUM_PARTIAL)
-                                       skb->csum = csum_partial(skb->data,
-                                                                skb->len, 0);
                        } else {
                                __pskb_trim_head(skb, copy);
                                tcp_set_skb_tso_segs(skb, mss_now);
@@ -2746,12 +2724,6 @@ static bool tcp_collapse_retrans(struct sock *sk, struct sk_buff *skb)
        }
        tcp_highest_sack_replace(sk, next_skb, skb);
 
-       if (next_skb->ip_summed == CHECKSUM_PARTIAL)
-               skb->ip_summed = CHECKSUM_PARTIAL;
-
-       if (skb->ip_summed != CHECKSUM_PARTIAL)
-               skb->csum = csum_block_add(skb->csum, next_skb->csum, skb_size);
-
        /* Update sequence range on original skb. */
        TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(next_skb)->end_seq;