Restructure the OSN xmit path to handle misaligned HW headers properly,
without shifting the packet data around.
Signed-off-by: Julian Wiedmann <j...@linux.ibm.com>
---
drivers/s390/net/qeth_core.h | 1 -
drivers/s390/net/qeth_core_main.c | 21 ---------------------
drivers/s390/net/qeth_l2_main.c | 37 ++++++++++++++++++++++++++++---------
3 files changed, 28 insertions(+), 31 deletions(-)
diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h
index 1c9fce609eb9..be213b5c2552 100644
--- a/drivers/s390/net/qeth_core.h
+++ b/drivers/s390/net/qeth_core.h
@@ -1021,7 +1021,6 @@ void qeth_dbf_longtext(debug_info_t *id, int level, char
*text, ...);
int qeth_core_ethtool_get_link_ksettings(struct net_device *netdev,
struct ethtool_link_ksettings *cmd);
int qeth_set_access_ctrl_online(struct qeth_card *card, int fallback);
-int qeth_hdr_chk_and_bounce(struct sk_buff *, struct qeth_hdr **, int);
int qeth_configure_cq(struct qeth_card *, enum qeth_cq);
int qeth_hw_trap(struct qeth_card *, enum qeth_diags_trap_action);
void qeth_trace_features(struct qeth_card *);
diff --git a/drivers/s390/net/qeth_core_main.c
b/drivers/s390/net/qeth_core_main.c
index 7426167eace2..c7f7061a7205 100644
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -3823,27 +3823,6 @@ unsigned int qeth_count_elements(struct sk_buff *skb,
unsigned int data_offset)
}
EXPORT_SYMBOL_GPL(qeth_count_elements);
-int qeth_hdr_chk_and_bounce(struct sk_buff *skb, struct qeth_hdr **hdr, int
len)
-{
- int hroom, inpage, rest;
-
- if (((unsigned long)skb->data & PAGE_MASK) !=
- (((unsigned long)skb->data + len - 1) & PAGE_MASK)) {
- hroom = skb_headroom(skb);
- inpage = PAGE_SIZE - ((unsigned long) skb->data % PAGE_SIZE);
- rest = len - inpage;
- if (rest > hroom)
- return 1;
- memmove(skb->data - rest, skb->data, skb_headlen(skb));
- skb->data -= rest;
- skb->tail -= rest;
- *hdr = (struct qeth_hdr *)skb->data;
- QETH_DBF_MESSAGE(2, "skb bounce len: %d rest: %d\n", len, rest);
- }
- return 0;
-}
-EXPORT_SYMBOL_GPL(qeth_hdr_chk_and_bounce);
-
#define QETH_HDR_CACHE_OBJ_SIZE (sizeof(struct qeth_hdr_tso) + \
MAX_TCP_HEADER)
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,
--
2.16.4
