ch_ktls: fix build warning for ipv4-only config

When CONFIG_IPV6 is disabled, clang complains that a variable
is uninitialized for non-IPv4 data:

drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c:1046:6: error: variable 'cntrl1' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
        if (tx_info->ip_family == AF_INET) {
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c:1059:2: note: uninitialized use occurs here
        cntrl1 |= T6_TXPKT_ETHHDR_LEN_V(maclen - ETH_HLEN) |
        ^~~~~~

Replace the preprocessor conditional with the corresponding C version,
and make the ipv4 case unconditional in this configuration to improve
readability and avoid the warning.

Fixes: 86716b51d14f ("ch_ktls: Update cheksum information")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20201203222641.964234-1-arnd@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c b/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c
index 7f90b82..1b7e8c9 100644 (file)
--- a/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c
+++ b/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c
@@ -987,9 +987,7 @@ chcr_ktls_write_tcp_options(struct chcr_ktls_info *tx_info, struct sk_buff *skb,
        struct fw_eth_tx_pkt_wr *wr;
        struct cpl_tx_pkt_core *cpl;
        u32 ctrl, iplen, maclen;
-#if IS_ENABLED(CONFIG_IPV6)
        struct ipv6hdr *ip6;
-#endif
        unsigned int ndesc;
        struct tcphdr *tcp;
        int len16, pktlen;
@@ -1043,17 +1041,15 @@ chcr_ktls_write_tcp_options(struct chcr_ktls_info *tx_info, struct sk_buff *skb,
        cpl->len = htons(pktlen);
 
        memcpy(buf, skb->data, pktlen);
-       if (tx_info->ip_family == AF_INET) {
+       if (!IS_ENABLED(CONFIG_IPV6) || tx_info->ip_family == AF_INET) {
                /* we need to correct ip header len */
                ip = (struct iphdr *)(buf + maclen);
                ip->tot_len = htons(pktlen - maclen);
                cntrl1 = TXPKT_CSUM_TYPE_V(TX_CSUM_TCPIP);
-#if IS_ENABLED(CONFIG_IPV6)
        } else {
                ip6 = (struct ipv6hdr *)(buf + maclen);
                ip6->payload_len = htons(pktlen - maclen - iplen);
                cntrl1 = TXPKT_CSUM_TYPE_V(TX_CSUM_TCPIP6);
-#endif
        }
 
        cntrl1 |= T6_TXPKT_ETHHDR_LEN_V(maclen - ETH_HLEN) |