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Subject[PATCH net-next 2/8] net: qualcomm: rmnet: rearrange some NOTs
Date
With the ones' complement arithmetic, the sum of two negated values
is equal to the negation of the sum of the two original values [1].
Rearrange the calculation ip6_payload_sum using this property.

[1] https://tools.ietf.org/html/rfc1071

Signed-off-by: Alex Elder <elder@linaro.org>
---
drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c
index 3e6feef0fd252..1b170e9189d8a 100644
--- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c
+++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c
@@ -140,8 +140,8 @@ rmnet_map_ipv6_dl_csum_trailer(struct sk_buff *skb,
* checksum computed over the pseudo header.
*/
ip_header_csum = (__force __be16)ip_fast_csum(ip6h, sizeof(*ip6h) / 4);
- ip6_payload_csum = csum16_sub((__force __sum16)~csum_trailer->csum_value,
- ~ip_header_csum);
+ ip6_payload_csum = ~csum16_sub((__force __sum16)csum_trailer->csum_value,
+ ip_header_csum);

length = (ip6h->nexthdr == IPPROTO_UDP) ?
ntohs(((struct udphdr *)txporthdr)->len) :
--
2.27.0
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