From 69d7ce80df6d0d2fdbb8f0ff9ec4643aabfa6b99 Mon Sep 17 00:00:00 2001 From: Julian Wiedmann Date: Mon, 17 Sep 2018 17:36:04 +0200 Subject: s390/qeth: remove qeth_hdr_chk_and_bounce() Restructure the OSN xmit path to handle misaligned HW headers properly, without shifting the packet data around. Signed-off-by: Julian Wiedmann Signed-off-by: David S. Miller --- drivers/s390/net/qeth_l2_main.c | 37 ++++++++++++++++++++++++++++--------- 1 file changed, 28 insertions(+), 9 deletions(-) (limited to 'drivers/s390/net/qeth_l2_main.c') diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c index 24b531ca2827..33b65471a68a 100644 --- a/drivers/s390/net/qeth_l2_main.c +++ b/drivers/s390/net/qeth_l2_main.c @@ -650,19 +650,38 @@ static void qeth_l2_set_rx_mode(struct net_device *dev) static int qeth_l2_xmit_osn(struct qeth_card *card, struct sk_buff *skb, struct qeth_qdio_out_q *queue) { - unsigned int elements; - struct qeth_hdr *hdr; + struct qeth_hdr *hdr = (struct qeth_hdr *)skb->data; + addr_t end = (addr_t)(skb->data + sizeof(*hdr)); + addr_t start = (addr_t)skb->data; + unsigned int elements = 0; + unsigned int hd_len = 0; + int rc; if (skb->protocol == htons(ETH_P_IPV6)) return -EPROTONOSUPPORT; - hdr = (struct qeth_hdr *)skb->data; - elements = qeth_count_elements(skb, 0); - if (elements > QETH_MAX_BUFFER_ELEMENTS(card)) - return -E2BIG; - if (qeth_hdr_chk_and_bounce(skb, &hdr, sizeof(*hdr))) - return -EINVAL; - return qeth_do_send_packet(card, queue, skb, hdr, 0, 0, elements); + if (qeth_get_elements_for_range(start, end) > 1) { + /* Misaligned HW header, move it to its own buffer element. */ + hdr = kmem_cache_alloc(qeth_core_header_cache, GFP_ATOMIC); + if (!hdr) + return -ENOMEM; + hd_len = sizeof(*hdr); + skb_copy_from_linear_data(skb, (char *)hdr, hd_len); + elements++; + } + + elements += qeth_count_elements(skb, hd_len); + if (elements > QETH_MAX_BUFFER_ELEMENTS(card)) { + rc = -E2BIG; + goto out; + } + + rc = qeth_do_send_packet(card, queue, skb, hdr, hd_len, hd_len, + elements); +out: + if (rc && hd_len) + kmem_cache_free(qeth_core_header_cache, hdr); + return rc; } static netdev_tx_t qeth_l2_hard_start_xmit(struct sk_buff *skb, -- cgit v1.2.3-55-g7522