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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , "Michael S. Tsirkin" , Xuan Zhuo , Shuah Khan , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-kselftest@vger.kernel.org, Yuri Benditovich , Andrew Melnychenko , Stephen Hemminger , gur.stavi@huawei.com, devel@daynix.com, Akihiko Odaki X-Mailer: b4 0.14-dev-fd6e3 hdr_len is repeatedly used so keep it in a local variable. Signed-off-by: Akihiko Odaki --- drivers/net/tap.c | 17 +++++++---------- 1 file changed, 7 insertions(+), 10 deletions(-) diff --git a/drivers/net/tap.c b/drivers/net/tap.c index 061c2f27dfc8..7ee2e9ee2a89 100644 --- a/drivers/net/tap.c +++ b/drivers/net/tap.c @@ -645,6 +645,7 @@ static ssize_t tap_get_user(struct tap_queue *q, void *= msg_control, int err; struct virtio_net_hdr vnet_hdr =3D { 0 }; int vnet_hdr_len =3D 0; + int hdr_len =3D 0; int copylen =3D 0; int depth; bool zerocopy =3D false; @@ -672,6 +673,7 @@ static ssize_t tap_get_user(struct tap_queue *q, void *= msg_control, err =3D -EINVAL; if (tap16_to_cpu(q, vnet_hdr.hdr_len) > iov_iter_count(from)) goto err; + hdr_len =3D tap16_to_cpu(q, vnet_hdr.hdr_len); } =20 len =3D iov_iter_count(from); @@ -683,11 +685,8 @@ static ssize_t tap_get_user(struct tap_queue *q, void = *msg_control, if (msg_control && sock_flag(&q->sk, SOCK_ZEROCOPY)) { struct iov_iter i; =20 - copylen =3D vnet_hdr.hdr_len ? - tap16_to_cpu(q, vnet_hdr.hdr_len) : GOODCOPY_LEN; - if (copylen > good_linear) - copylen =3D good_linear; - else if (copylen < ETH_HLEN) + copylen =3D min(hdr_len ? hdr_len : GOODCOPY_LEN, good_linear); + if (copylen < ETH_HLEN) copylen =3D ETH_HLEN; linear =3D copylen; i =3D *from; @@ -698,11 +697,9 @@ static ssize_t tap_get_user(struct tap_queue *q, void = *msg_control, =20 if (!zerocopy) { copylen =3D len; - linear =3D tap16_to_cpu(q, vnet_hdr.hdr_len); - if (linear > good_linear) - linear =3D good_linear; - else if (linear < ETH_HLEN) - linear =3D ETH_HLEN; + linear =3D min(hdr_len, good_linear); + if (copylen < ETH_HLEN) + copylen =3D ETH_HLEN; } =20 skb =3D tap_alloc_skb(&q->sk, TAP_RESERVE, copylen, --=20 2.47.1