Merge branch 's390-qeth-next'

Julian Wiedmann says:

====================
s390/qeth: updates 2018-09-17

please apply the following patchset to net-next. This brings more restructuring
of qeth's transmit code (eliminating its last usage of skb_realloc_headroom()),
and the usual mix of minor improvements & cleanups.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 334 insertions, 446 deletions

diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h
index 34e0d476c5c6..0dbe81f958f0 100644
--- a/drivers/s390/net/qeth_core.h
+++ b/drivers/s390/net/qeth_core.h
@@ -26,6 +26,7 @@
 #include <net/ipv6.h>
 #include <net/if_inet6.h>
 #include <net/addrconf.h>
+#include <net/tcp.h>
 
 #include <asm/debug.h>
 #include <asm/qdio.h>
@@ -638,7 +639,6 @@ struct qeth_reply {
 	atomic_t received;
 	int rc;
 	void *param;
-	struct qeth_card *card;
 	refcount_t refcnt;
 };
 
@@ -892,11 +892,6 @@ static inline void qeth_tx_csum(struct sk_buff *skb, u8 *flags, int ipv)
 	if ((ipv == 4 && ip_hdr(skb)->protocol == IPPROTO_UDP) ||
 	    (ipv == 6 && ipv6_hdr(skb)->nexthdr == IPPROTO_UDP))
 		*flags |= QETH_HDR_EXT_UDP;
-	if (ipv == 4) {
-		/* some HW requires combined L3+L4 csum offload: */
-		*flags |= QETH_HDR_EXT_CSUM_HDR_REQ;
-		ip_hdr(skb)->check = 0;
-	}
 }
 
 static inline void qeth_put_buffer_pool_entry(struct qeth_card *card,
@@ -1007,9 +1002,7 @@ int qeth_query_switch_attributes(struct qeth_card *card,
 int qeth_send_control_data(struct qeth_card *, int, struct qeth_cmd_buffer *,
 	int (*reply_cb)(struct qeth_card *, struct qeth_reply*, unsigned long),
 	void *reply_param);
-int qeth_get_elements_no(struct qeth_card *card, struct sk_buff *skb,
-			 int extra_elems, int data_offset);
-int qeth_get_elements_for_frags(struct sk_buff *);
+unsigned int qeth_count_elements(struct sk_buff *skb, unsigned int data_offset);
 int qeth_do_send_packet_fast(struct qeth_qdio_out_q *queue, struct sk_buff *skb,
 			     struct qeth_hdr *hdr, unsigned int offset,
 			     unsigned int hd_len);
@@ -1027,7 +1020,6 @@ 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 *);
@@ -1052,6 +1044,11 @@ int qeth_vm_request_mac(struct qeth_card *card);
 int qeth_add_hw_header(struct qeth_card *card, struct sk_buff *skb,
 		       struct qeth_hdr **hdr, unsigned int hdr_len,
 		       unsigned int proto_len, unsigned int *elements);
+int qeth_xmit(struct qeth_card *card, struct sk_buff *skb,
+	      struct qeth_qdio_out_q *queue, int ipv, int cast_type,
+	      void (*fill_header)(struct qeth_card *card, struct qeth_hdr *hdr,
+				  struct sk_buff *skb, int ipv, int cast_type,
+				  unsigned int data_len));
 
 /* exports for OSN */
 int qeth_osn_assist(struct net_device *, void *, int);
diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index de8282420f96..89e09e7b8fff 100644
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -16,6 +16,7 @@
 #include <linux/string.h>
 #include <linux/errno.h>
 #include <linux/kernel.h>
+#include <linux/log2.h>
 #include <linux/ip.h>
 #include <linux/tcp.h>
 #include <linux/mii.h>
@@ -591,7 +592,6 @@ static struct qeth_reply *qeth_alloc_reply(struct qeth_card *card)
 	if (reply) {
 		refcount_set(&reply->refcnt, 1);
 		atomic_set(&reply->received, 0);
-		reply->card = card;
 	}
 	return reply;
 }
@@ -780,7 +780,6 @@ void qeth_release_buffer(struct qeth_channel *channel,
 
 	QETH_CARD_TEXT(CARD_FROM_CDEV(channel->ccwdev), 6, "relbuff");
 	spin_lock_irqsave(&channel->iob_lock, flags);
-	memset(iob->data, 0, QETH_BUFSIZE);
 	iob->state = BUF_STATE_FREE;
 	iob->callback = qeth_send_control_data_cb;
 	iob->rc = 0;
@@ -900,44 +899,6 @@ out:
 	qeth_release_buffer(channel, iob);
 }
 
-static int qeth_setup_channel(struct qeth_channel *channel, bool alloc_buffers)
-{
-	int cnt;
-
-	QETH_DBF_TEXT(SETUP, 2, "setupch");
-
-	channel->ccw = kmalloc(sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
-	if (!channel->ccw)
-		return -ENOMEM;
-	channel->state = CH_STATE_DOWN;
-	atomic_set(&channel->irq_pending, 0);
-	init_waitqueue_head(&channel->wait_q);
-
-	if (!alloc_buffers)
-		return 0;
-
-	for (cnt = 0; cnt < QETH_CMD_BUFFER_NO; cnt++) {
-		channel->iob[cnt].data =
-			kzalloc(QETH_BUFSIZE, GFP_DMA|GFP_KERNEL);
-		if (channel->iob[cnt].data == NULL)
-			break;
-		channel->iob[cnt].state = BUF_STATE_FREE;
-		channel->iob[cnt].channel = channel;
-		channel->iob[cnt].callback = qeth_send_control_data_cb;
-		channel->iob[cnt].rc = 0;
-	}
-	if (cnt < QETH_CMD_BUFFER_NO) {
-		kfree(channel->ccw);
-		while (cnt-- > 0)
-			kfree(channel->iob[cnt].data);
-		return -ENOMEM;
-	}
-	channel->io_buf_no = 0;
-	spin_lock_init(&channel->iob_lock);
-
-	return 0;
-}
-
 static int qeth_set_thread_start_bit(struct qeth_card *card,
 		unsigned long thread)
 {
@@ -1336,14 +1297,61 @@ static void qeth_free_buffer_pool(struct qeth_card *card)
 
 static void qeth_clean_channel(struct qeth_channel *channel)
 {
+	struct ccw_device *cdev = channel->ccwdev;
 	int cnt;
 
 	QETH_DBF_TEXT(SETUP, 2, "freech");
+
+	spin_lock_irq(get_ccwdev_lock(cdev));
+	cdev->handler = NULL;
+	spin_unlock_irq(get_ccwdev_lock(cdev));
+
 	for (cnt = 0; cnt < QETH_CMD_BUFFER_NO; cnt++)
 		kfree(channel->iob[cnt].data);
 	kfree(channel->ccw);
 }
 
+static int qeth_setup_channel(struct qeth_channel *channel, bool alloc_buffers)
+{
+	struct ccw_device *cdev = channel->ccwdev;
+	int cnt;
+
+	QETH_DBF_TEXT(SETUP, 2, "setupch");
+
+	channel->ccw = kmalloc(sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
+	if (!channel->ccw)
+		return -ENOMEM;
+	channel->state = CH_STATE_DOWN;
+	atomic_set(&channel->irq_pending, 0);
+	init_waitqueue_head(&channel->wait_q);
+
+	spin_lock_irq(get_ccwdev_lock(cdev));
+	cdev->handler = qeth_irq;
+	spin_unlock_irq(get_ccwdev_lock(cdev));
+
+	if (!alloc_buffers)
+		return 0;
+
+	for (cnt = 0; cnt < QETH_CMD_BUFFER_NO; cnt++) {
+		channel->iob[cnt].data = kmalloc(QETH_BUFSIZE,
+						 GFP_KERNEL | GFP_DMA);
+		if (channel->iob[cnt].data == NULL)
+			break;
+		channel->iob[cnt].state = BUF_STATE_FREE;
+		channel->iob[cnt].channel = channel;
+		channel->iob[cnt].callback = qeth_send_control_data_cb;
+		channel->iob[cnt].rc = 0;
+	}
+	if (cnt < QETH_CMD_BUFFER_NO) {
+		qeth_clean_channel(channel);
+		return -ENOMEM;
+	}
+	channel->io_buf_no = 0;
+	spin_lock_init(&channel->iob_lock);
+
+	return 0;
+}
+
 static void qeth_set_single_write_queues(struct qeth_card *card)
 {
 	if ((atomic_read(&card->qdio.state) != QETH_QDIO_UNINITIALIZED) &&
@@ -1494,7 +1502,7 @@ static void qeth_core_sl_print(struct seq_file *m, struct service_level *slr)
 			CARD_BUS_ID(card), card->info.mcl_level);
 }
 
-static struct qeth_card *qeth_alloc_card(void)
+static struct qeth_card *qeth_alloc_card(struct ccwgroup_device *gdev)
 {
 	struct qeth_card *card;
 
@@ -1503,6 +1511,11 @@ static struct qeth_card *qeth_alloc_card(void)
 	if (!card)
 		goto out;
 	QETH_DBF_HEX(SETUP, 2, &card, sizeof(void *));
+
+	card->gdev = gdev;
+	CARD_RDEV(card) = gdev->cdev[0];
+	CARD_WDEV(card) = gdev->cdev[1];
+	CARD_DDEV(card) = gdev->cdev[2];
 	if (qeth_setup_channel(&card->read, true))
 		goto out_ip;
 	if (qeth_setup_channel(&card->write, true))
@@ -1526,15 +1539,14 @@ out:
 
 static int qeth_clear_channel(struct qeth_channel *channel)
 {
-	unsigned long flags;
 	struct qeth_card *card;
 	int rc;
 
 	card = CARD_FROM_CDEV(channel->ccwdev);
 	QETH_CARD_TEXT(card, 3, "clearch");
-	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);
+	spin_lock_irq(get_ccwdev_lock(channel->ccwdev));
 	rc = ccw_device_clear(channel->ccwdev, QETH_CLEAR_CHANNEL_PARM);
-	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);
+	spin_unlock_irq(get_ccwdev_lock(channel->ccwdev));
 
 	if (rc)
 		return rc;
@@ -1550,15 +1562,14 @@ static int qeth_clear_channel(struct qeth_channel *channel)
 
 static int qeth_halt_channel(struct qeth_channel *channel)
 {
-	unsigned long flags;
 	struct qeth_card *card;
 	int rc;
 
 	card = CARD_FROM_CDEV(channel->ccwdev);
 	QETH_CARD_TEXT(card, 3, "haltch");
-	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);
+	spin_lock_irq(get_ccwdev_lock(channel->ccwdev));
 	rc = ccw_device_halt(channel->ccwdev, QETH_HALT_CHANNEL_PARM);
-	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);
+	spin_unlock_irq(get_ccwdev_lock(channel->ccwdev));
 
 	if (rc)
 		return rc;
@@ -1652,7 +1663,6 @@ static int qeth_read_conf_data(struct qeth_card *card, void **buffer,
 	char *rcd_buf;
 	int ret;
 	struct qeth_channel *channel = &card->data;
-	unsigned long flags;
 
 	/*
 	 * scan for RCD command in extended SenseID data
@@ -1666,11 +1676,11 @@ static int qeth_read_conf_data(struct qeth_card *card, void **buffer,
 
 	qeth_setup_ccw(channel->ccw, ciw->cmd, ciw->count, rcd_buf);
 	channel->state = CH_STATE_RCD;
-	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);
+	spin_lock_irq(get_ccwdev_lock(channel->ccwdev));
 	ret = ccw_device_start_timeout(channel->ccwdev, channel->ccw,
 				       QETH_RCD_PARM, LPM_ANYPATH, 0,
 				       QETH_RCD_TIMEOUT);
-	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);
+	spin_unlock_irq(get_ccwdev_lock(channel->ccwdev));
 	if (!ret)
 		wait_event(card->wait_q,
 			   (channel->state == CH_STATE_RCD_DONE ||
@@ -1828,7 +1838,6 @@ static int qeth_idx_activate_get_answer(struct qeth_channel *channel,
 			struct qeth_cmd_buffer *))
 {
 	struct qeth_cmd_buffer *iob;
-	unsigned long flags;
 	int rc;
 	struct qeth_card *card;
 
@@ -1843,10 +1852,10 @@ static int qeth_idx_activate_get_answer(struct qeth_channel *channel,
 	wait_event(card->wait_q,
 		   atomic_cmpxchg(&channel->irq_pending, 0, 1) == 0);
 	QETH_DBF_TEXT(SETUP, 6, "noirqpnd");
-	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);
+	spin_lock_irq(get_ccwdev_lock(channel->ccwdev));
 	rc = ccw_device_start_timeout(channel->ccwdev, channel->ccw,
 				      (addr_t) iob, 0, 0, QETH_TIMEOUT);
-	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);
+	spin_unlock_irq(get_ccwdev_lock(channel->ccwdev));
 
 	if (rc) {
 		QETH_DBF_MESSAGE(2, "Error2 in activating channel rc=%d\n", rc);
@@ -1873,7 +1882,6 @@ static int qeth_idx_activate_channel(struct qeth_channel *channel,
 {
 	struct qeth_card *card;
 	struct qeth_cmd_buffer *iob;
-	unsigned long flags;
 	__u16 temp;
 	__u8 tmp;
 	int rc;
@@ -1913,10 +1921,10 @@ static int qeth_idx_activate_channel(struct qeth_channel *channel,
 	wait_event(card->wait_q,
 		   atomic_cmpxchg(&channel->irq_pending, 0, 1) == 0);
 	QETH_DBF_TEXT(SETUP, 6, "noirqpnd");
-	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);
+	spin_lock_irq(get_ccwdev_lock(channel->ccwdev));
 	rc = ccw_device_start_timeout(channel->ccwdev, channel->ccw,
 				      (addr_t) iob, 0, 0, QETH_TIMEOUT);
-	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);
+	spin_unlock_irq(get_ccwdev_lock(channel->ccwdev));
 
 	if (rc) {
 		QETH_DBF_MESSAGE(2, "Error1 in activating channel. rc=%d\n",
@@ -2097,7 +2105,6 @@ int qeth_send_control_data(struct qeth_card *card, int len,
 {
 	struct qeth_channel *channel = iob->channel;
 	int rc;
-	unsigned long flags;
 	struct qeth_reply *reply = NULL;
 	unsigned long timeout, event_timeout;
 	struct qeth_ipa_cmd *cmd = NULL;
@@ -2130,26 +2137,26 @@ int qeth_send_control_data(struct qeth_card *card, int len,
 	}
 	qeth_prepare_control_data(card, len, iob);
 
-	spin_lock_irqsave(&card->lock, flags);
+	spin_lock_irq(&card->lock);
 	list_add_tail(&reply->list, &card->cmd_waiter_list);
-	spin_unlock_irqrestore(&card->lock, flags);
+	spin_unlock_irq(&card->lock);
 
 	timeout = jiffies + event_timeout;
 
 	QETH_CARD_TEXT(card, 6, "noirqpnd");
-	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);
+	spin_lock_irq(get_ccwdev_lock(channel->ccwdev));
 	rc = ccw_device_start_timeout(channel->ccwdev, channel->ccw,
 				      (addr_t) iob, 0, 0, event_timeout);
-	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);
+	spin_unlock_irq(get_ccwdev_lock(channel->ccwdev));
 	if (rc) {
 		QETH_DBF_MESSAGE(2, "%s qeth_send_control_data: "
 			"ccw_device_start rc = %i\n",
 			dev_name(&channel->ccwdev->dev), rc);
 		QETH_CARD_TEXT_(card, 2, " err%d", rc);
-		spin_lock_irqsave(&card->lock, flags);
+		spin_lock_irq(&card->lock);
 		list_del_init(&reply->list);
 		qeth_put_reply(reply);
-		spin_unlock_irqrestore(&card->lock, flags);
+		spin_unlock_irq(&card->lock);
 		qeth_release_buffer(channel, iob);
 		atomic_set(&channel->irq_pending, 0);
 		wake_up(&card->wait_q);
@@ -2177,9 +2184,9 @@ int qeth_send_control_data(struct qeth_card *card, int len,
 
 time_err:
 	reply->rc = -ETIME;
-	spin_lock_irqsave(&reply->card->lock, flags);
+	spin_lock_irq(&card->lock);
 	list_del_init(&reply->list);
-	spin_unlock_irqrestore(&reply->card->lock, flags);
+	spin_unlock_irq(&card->lock);
 	atomic_inc(&reply->received);
 	rc = reply->rc;
 	qeth_put_reply(reply);
@@ -2880,10 +2887,10 @@ static __u8 qeth_get_ipa_adp_type(enum qeth_link_types link_type)
 }
 
 static void qeth_fill_ipacmd_header(struct qeth_card *card,
-		struct qeth_ipa_cmd *cmd, __u8 command,
-		enum qeth_prot_versions prot)
+				    struct qeth_ipa_cmd *cmd,
+				    enum qeth_ipa_cmds command,
+				    enum qeth_prot_versions prot)
 {
-	memset(cmd, 0, sizeof(struct qeth_ipa_cmd));
 	cmd->hdr.command = command;
 	cmd->hdr.initiator = IPA_CMD_INITIATOR_HOST;
 	/* cmd->hdr.seqno is set by qeth_send_control_data() */
@@ -2895,8 +2902,6 @@ static void qeth_fill_ipacmd_header(struct qeth_card *card,
 		cmd->hdr.prim_version_no = 1;
 	cmd->hdr.param_count = 1;
 	cmd->hdr.prot_version = prot;
-	cmd->hdr.ipa_supported = 0;
-	cmd->hdr.ipa_enabled = 0;
 }
 
 struct qeth_cmd_buffer *qeth_get_ipacmd_buffer(struct qeth_card *card,
@@ -3043,7 +3048,7 @@ static int qeth_query_ipassists_cb(struct qeth_card *card,
 		QETH_DBF_TEXT(SETUP, 2, "ipaunsup");
 		card->options.ipa4.supported_funcs |= IPA_SETADAPTERPARMS;
 		card->options.ipa6.supported_funcs |= IPA_SETADAPTERPARMS;
-		return -0;
+		return 0;
 	default:
 		if (cmd->hdr.return_code) {
 			QETH_DBF_MESSAGE(1, "%s IPA_CMD_QIPASSIST: Unhandled "
@@ -3787,7 +3792,7 @@ EXPORT_SYMBOL_GPL(qeth_get_priority_queue);
  * Returns the number of pages, and thus QDIO buffer elements, needed to cover
  * fragmented part of the SKB. Returns zero for linear SKB.
  */
-int qeth_get_elements_for_frags(struct sk_buff *skb)
+static int qeth_get_elements_for_frags(struct sk_buff *skb)
 {
 	int cnt, elements = 0;
 
@@ -3800,9 +3805,17 @@ int qeth_get_elements_for_frags(struct sk_buff *skb)
 	}
 	return elements;
 }
-EXPORT_SYMBOL_GPL(qeth_get_elements_for_frags);
 
-static unsigned int qeth_count_elements(struct sk_buff *skb, int data_offset)
+/**
+ * qeth_count_elements() -	Counts the number of QDIO buffer elements needed
+ *				to transmit an skb.
+ * @skb:			the skb to operate on.
+ * @data_offset:		skip this part of the skb's linear data
+ *
+ * Returns the number of pages, and thus QDIO buffer elements, needed to map the
+ * skb's data (both its linear part and paged fragments).
+ */
+unsigned int qeth_count_elements(struct sk_buff *skb, unsigned int data_offset)
 {
 	unsigned int elements = qeth_get_elements_for_frags(skb);
 	addr_t end = (addr_t)skb->data + skb_headlen(skb);
@@ -3812,54 +3825,10 @@ static unsigned int qeth_count_elements(struct sk_buff *skb, int data_offset)
 		elements += qeth_get_elements_for_range(start, end);
 	return elements;
 }
+EXPORT_SYMBOL_GPL(qeth_count_elements);
 
-/**
- * qeth_get_elements_no() -	find number of SBALEs for skb data, inc. frags.
- * @card:			qeth card structure, to check max. elems.
- * @skb:			SKB address
- * @extra_elems:		extra elems needed, to check against max.
- * @data_offset:		range starts at skb->data + data_offset
- *
- * Returns the number of pages, and thus QDIO buffer elements, needed to cover
- * skb data, including linear part and fragments. Checks if the result plus
- * extra_elems fits under the limit for the card. Returns 0 if it does not.
- * Note: extra_elems is not included in the returned result.
- */
-int qeth_get_elements_no(struct qeth_card *card,
-		     struct sk_buff *skb, int extra_elems, int data_offset)
-{
-	int elements = qeth_count_elements(skb, data_offset);
-
-	if ((elements + extra_elems) > QETH_MAX_BUFFER_ELEMENTS(card)) {
-		QETH_DBF_MESSAGE(2, "Invalid size of IP packet "
-			"(Number=%d / Length=%d). Discarded.\n",
-			elements + extra_elems, skb->len);
-		return 0;
-	}
-	return elements;
-}
-EXPORT_SYMBOL_GPL(qeth_get_elements_no);
-
-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)
 
 /**
  * qeth_add_hw_header() - add a HW header to an skb.
@@ -3894,7 +3863,11 @@ check_layout:
 	if (qeth_get_elements_for_range(start, end + contiguous) == 1) {
 		/* Push HW header into same page as first protocol header. */
 		push_ok = true;
-		__elements = qeth_count_elements(skb, 0);
+		/* ... but TSO always needs a separate element for headers: */
+		if (skb_is_gso(skb))
+			__elements = 1 + qeth_count_elements(skb, proto_len);
+		else
+			__elements = qeth_count_elements(skb, 0);
 	} else if (!proto_len && qeth_get_elements_for_range(start, end) == 1) {
 		/* Push HW header into a new page. */
 		push_ok = true;
@@ -3935,6 +3908,8 @@ check_layout:
 		return hdr_len;
 	}
 	/* fall back */
+	if (hdr_len + proto_len > QETH_HDR_CACHE_OBJ_SIZE)
+		return -E2BIG;
 	*hdr = kmem_cache_alloc(qeth_core_header_cache, GFP_ATOMIC);
 	if (!*hdr)
 		return -ENOMEM;
@@ -4176,6 +4151,66 @@ out:
 }
 EXPORT_SYMBOL_GPL(qeth_do_send_packet);
 
+int qeth_xmit(struct qeth_card *card, struct sk_buff *skb,
+	      struct qeth_qdio_out_q *queue, int ipv, int cast_type,
+	      void (*fill_header)(struct qeth_card *card, struct qeth_hdr *hdr,
+				  struct sk_buff *skb, int ipv, int cast_type,
+				  unsigned int data_len))
+{
+	const unsigned int proto_len = IS_IQD(card) ? ETH_HLEN : 0;
+	const unsigned int hw_hdr_len = sizeof(struct qeth_hdr);
+	unsigned int frame_len = skb->len;
+	unsigned int data_offset = 0;
+	struct qeth_hdr *hdr = NULL;
+	unsigned int hd_len = 0;
+	unsigned int elements;
+	int push_len, rc;
+	bool is_sg;
+
+	rc = skb_cow_head(skb, hw_hdr_len);
+	if (rc)
+		return rc;
+
+	push_len = qeth_add_hw_header(card, skb, &hdr, hw_hdr_len, proto_len,
+				      &elements);
+	if (push_len < 0)
+		return push_len;
+	if (!push_len) {
+		/* HW header needs its own buffer element. */
+		hd_len = hw_hdr_len + proto_len;
+		data_offset = proto_len;
+	}
+	memset(hdr, 0, hw_hdr_len);
+	fill_header(card, hdr, skb, ipv, cast_type, frame_len);
+
+	is_sg = skb_is_nonlinear(skb);
+	if (IS_IQD(card)) {
+		rc = qeth_do_send_packet_fast(queue, skb, hdr, data_offset,
+					      hd_len);
+	} else {
+		/* TODO: drop skb_orphan() once TX completion is fast enough */
+		skb_orphan(skb);
+		rc = qeth_do_send_packet(card, queue, skb, hdr, data_offset,
+					 hd_len, elements);
+	}
+
+	if (!rc) {
+		if (card->options.performance_stats) {
+			card->perf_stats.buf_elements_sent += elements;
+			if (is_sg)
+				card->perf_stats.sg_skbs_sent++;
+		}
+	} else {
+		if (!push_len)
+			kmem_cache_free(qeth_core_header_cache, hdr);
+		if (rc == -EBUSY)
+			/* roll back to ETH header */
+			skb_pull(skb, push_len);
+	}
+	return rc;
+}
+EXPORT_SYMBOL_GPL(qeth_xmit);
+
 static int qeth_setadp_promisc_mode_cb(struct qeth_card *card,
 		struct qeth_reply *reply, unsigned long data)
 {
@@ -5456,8 +5491,6 @@ struct qeth_cmd_buffer *qeth_get_setassparms_cmd(struct qeth_card *card,
 		cmd->data.setassparms.hdr.assist_no = ipa_func;
 		cmd->data.setassparms.hdr.length = 8 + len;
 		cmd->data.setassparms.hdr.command_code = cmd_code;
-		cmd->data.setassparms.hdr.return_code = 0;
-		cmd->data.setassparms.hdr.seq_no = 0;
 	}
 
 	return iob;
@@ -5731,7 +5764,6 @@ static int qeth_core_probe_device(struct ccwgroup_device *gdev)
 	struct device *dev;
 	int rc;
 	enum qeth_discipline_id enforced_disc;
-	unsigned long flags;
 	char dbf_name[DBF_NAME_LEN];
 
 	QETH_DBF_TEXT(SETUP, 2, "probedev");
@@ -5742,7 +5774,7 @@ static int qeth_core_probe_device(struct ccwgroup_device *gdev)
 
 	QETH_DBF_TEXT_(SETUP, 2, "%s", dev_name(&gdev->dev));
 
-	card = qeth_alloc_card();
+	card = qeth_alloc_card(gdev);
 	if (!card) {
 		QETH_DBF_TEXT_(SETUP, 2, "1err%d", -ENOMEM);
 		rc = -ENOMEM;
@@ -5758,15 +5790,7 @@ static int qeth_core_probe_device(struct ccwgroup_device *gdev)
 			goto err_card;
 	}
 
-	card->read.ccwdev  = gdev->cdev[0];
-	card->write.ccwdev = gdev->cdev[1];
-	card->data.ccwdev  = gdev->cdev[2];
 	dev_set_drvdata(&gdev->dev, card);
-	card->gdev = gdev;
-	gdev->cdev[0]->handler = qeth_irq;
-	gdev->cdev[1]->handler = qeth_irq;
-	gdev->cdev[2]->handler = qeth_irq;
-
 	qeth_setup_card(card);
 	qeth_update_from_chp_desc(card);
 
@@ -5797,9 +5821,9 @@ static int qeth_core_probe_device(struct ccwgroup_device *gdev)
 		break;
 	}
 
-	write_lock_irqsave(&qeth_core_card_list.rwlock, flags);
+	write_lock_irq(&qeth_core_card_list.rwlock);
 	list_add_tail(&card->list, &qeth_core_card_list.list);
-	write_unlock_irqrestore(&qeth_core_card_list.rwlock, flags);
+	write_unlock_irq(&qeth_core_card_list.rwlock);
 	return 0;
 
 err_disc:
@@ -5815,7 +5839,6 @@ err_dev:
 
 static void qeth_core_remove_device(struct ccwgroup_device *gdev)
 {
-	unsigned long flags;
 	struct qeth_card *card = dev_get_drvdata(&gdev->dev);
 
 	QETH_DBF_TEXT(SETUP, 2, "removedv");
@@ -5825,9 +5848,9 @@ static void qeth_core_remove_device(struct ccwgroup_device *gdev)
 		qeth_core_free_discipline(card);
 	}
 
-	write_lock_irqsave(&qeth_core_card_list.rwlock, flags);
+	write_lock_irq(&qeth_core_card_list.rwlock);
 	list_del(&card->list);
-	write_unlock_irqrestore(&qeth_core_card_list.rwlock, flags);
+	write_unlock_irq(&qeth_core_card_list.rwlock);
 	free_netdev(card->dev);
 	qeth_core_free_card(card);
 	dev_set_drvdata(&gdev->dev, NULL);
@@ -6619,8 +6642,10 @@ static int __init qeth_core_init(void)
 	rc = PTR_ERR_OR_ZERO(qeth_core_root_dev);
 	if (rc)
 		goto register_err;
-	qeth_core_header_cache = kmem_cache_create("qeth_hdr",
-			sizeof(struct qeth_hdr) + ETH_HLEN, 64, 0, NULL);
+	qeth_core_header_cache =
+		kmem_cache_create("qeth_hdr", QETH_HDR_CACHE_OBJ_SIZE,
+				  roundup_pow_of_two(QETH_HDR_CACHE_OBJ_SIZE),
+				  0, NULL);
 	if (!qeth_core_header_cache) {
 		rc = -ENOMEM;
 		goto slab_err;
diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c
index b5e38531733f..12858ffa28cf 100644
--- a/drivers/s390/net/qeth_l2_main.c
+++ b/drivers/s390/net/qeth_l2_main.c
@@ -193,15 +193,21 @@ static int qeth_l2_get_cast_type(struct qeth_card *card, struct sk_buff *skb)
 	return RTN_UNICAST;
 }
 
-static void qeth_l2_fill_header(struct qeth_hdr *hdr, struct sk_buff *skb,
-				int cast_type, unsigned int data_len)
+static void qeth_l2_fill_header(struct qeth_card *card, struct qeth_hdr *hdr,
+				struct sk_buff *skb, int ipv, int cast_type,
+				unsigned int data_len)
 {
 	struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb_mac_header(skb);
 
-	memset(hdr, 0, sizeof(struct qeth_hdr));
 	hdr->hdr.l2.id = QETH_HEADER_TYPE_LAYER2;
 	hdr->hdr.l2.pkt_length = data_len;
 
+	if (skb->ip_summed == CHECKSUM_PARTIAL) {
+		qeth_tx_csum(skb, &hdr->hdr.l2.flags[1], ipv);
+		if (card->options.performance_stats)
+			card->perf_stats.tx_csum++;
+	}
+
 	/* set byte byte 3 to casting flags */
 	if (cast_type == RTN_MULTICAST)
 		hdr->hdr.l2.flags[2] |= QETH_LAYER2_FLAG_MULTICAST;
@@ -641,84 +647,43 @@ static void qeth_l2_set_rx_mode(struct net_device *dev)
 		qeth_promisc_to_bridge(card);
 }
 
-static int qeth_l2_xmit(struct qeth_card *card, struct sk_buff *skb,
-			struct qeth_qdio_out_q *queue, int cast_type, int ipv)
+static int qeth_l2_xmit_osn(struct qeth_card *card, struct sk_buff *skb,
+			    struct qeth_qdio_out_q *queue)
 {
-	const unsigned int proto_len = IS_IQD(card) ? ETH_HLEN : 0;
-	const unsigned int hw_hdr_len = sizeof(struct qeth_hdr);
-	unsigned int frame_len = skb->len;
-	unsigned int data_offset = 0;
-	struct qeth_hdr *hdr = NULL;
+	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;
-	unsigned int elements;
-	int push_len, rc;
-	bool is_sg;
+	int rc;
 
-	rc = skb_cow_head(skb, hw_hdr_len);
-	if (rc)
-		return rc;
+	if (skb->protocol == htons(ETH_P_IPV6))
+		return -EPROTONOSUPPORT;
 
-	push_len = qeth_add_hw_header(card, skb, &hdr, hw_hdr_len, proto_len,
-				      &elements);
-	if (push_len < 0)
-		return push_len;
-	if (!push_len) {
-		/* HW header needs its own buffer element. */
-		hd_len = hw_hdr_len + proto_len;
-		data_offset = proto_len;
-	}
-	qeth_l2_fill_header(hdr, skb, cast_type, frame_len);
-	if (skb->ip_summed == CHECKSUM_PARTIAL) {
-		qeth_tx_csum(skb, &hdr->hdr.l2.flags[1], ipv);
-		if (card->options.performance_stats)
-			card->perf_stats.tx_csum++;
+	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++;
 	}
 
-	is_sg = skb_is_nonlinear(skb);
-	if (IS_IQD(card)) {
-		rc = qeth_do_send_packet_fast(queue, skb, hdr, data_offset,
-					      hd_len);
-	} else {
-		/* TODO: drop skb_orphan() once TX completion is fast enough */
-		skb_orphan(skb);
-		rc = qeth_do_send_packet(card, queue, skb, hdr, data_offset,
-					 hd_len, elements);
+	elements += qeth_count_elements(skb, hd_len);
+	if (elements > QETH_MAX_BUFFER_ELEMENTS(card)) {
+		rc = -E2BIG;
+		goto out;
 	}
 
-	if (!rc) {
-		if (card->options.performance_stats) {
-			card->perf_stats.buf_elements_sent += elements;
-			if (is_sg)
-				card->perf_stats.sg_skbs_sent++;
-		}
-	} else {
-		if (!push_len)
-			kmem_cache_free(qeth_core_header_cache, hdr);
-		if (rc == -EBUSY)
-			/* roll back to ETH header */
-			skb_pull(skb, push_len);
-	}
+	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 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;
-
-	if (skb->protocol == htons(ETH_P_IPV6))
-		return -EPROTONOSUPPORT;
-
-	hdr = (struct qeth_hdr *)skb->data;
-	elements = qeth_get_elements_no(card, skb, 0, 0);
-	if (!elements)
-		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);
-}
-
 static netdev_tx_t qeth_l2_hard_start_xmit(struct sk_buff *skb,
 					   struct net_device *dev)
 {
@@ -745,7 +710,8 @@ static netdev_tx_t qeth_l2_hard_start_xmit(struct sk_buff *skb,
 	if (IS_OSN(card))
 		rc = qeth_l2_xmit_osn(card, skb, queue);
 	else
-		rc = qeth_l2_xmit(card, skb, queue, cast_type, ipv);
+		rc = qeth_xmit(card, skb, queue, ipv, cast_type,
+			       qeth_l2_fill_header);
 
 	if (!rc) {
 		card->stats.tx_packets++;
@@ -789,7 +755,10 @@ static int __qeth_l2_open(struct net_device *dev)
 
 	if (qdio_stop_irq(card->data.ccwdev, 0) >= 0) {
 		napi_enable(&card->napi);
+		local_bh_disable();
 		napi_schedule(&card->napi);
+		/* kick-start the NAPI softirq: */
+		local_bh_enable();
 	} else
 		rc = -EIO;
 	return rc;
@@ -1240,7 +1209,6 @@ static int qeth_osn_send_control_data(struct qeth_card *card, int len,
 			   struct qeth_cmd_buffer *iob)
 {
 	struct qeth_channel *channel = iob->channel;
-	unsigned long flags;
 	int rc = 0;
 
 	QETH_CARD_TEXT(card, 5, "osndctrd");
@@ -1249,10 +1217,10 @@ static int qeth_osn_send_control_data(struct qeth_card *card, int len,
 		   atomic_cmpxchg(&channel->irq_pending, 0, 1) == 0);
 	qeth_prepare_control_data(card, len, iob);
 	QETH_CARD_TEXT(card, 6, "osnoirqp");
-	spin_lock_irqsave(get_ccwdev_lock(channel->ccwdev), flags);
+	spin_lock_irq(get_ccwdev_lock(channel->ccwdev));
 	rc = ccw_device_start_timeout(channel->ccwdev, channel->ccw,
 				      (addr_t) iob, 0, 0, QETH_IPA_TIMEOUT);
-	spin_unlock_irqrestore(get_ccwdev_lock(channel->ccwdev), flags);
+	spin_unlock_irq(get_ccwdev_lock(channel->ccwdev));
 	if (rc) {
 		QETH_DBF_MESSAGE(2, "qeth_osn_send_control_data: "
 			   "ccw_device_start rc = %i\n", rc);
diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c
index ada258c01a08..8930d2a9fcad 100644
--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -33,7 +33,6 @@
 #include <net/ipv6.h>
 #include <net/ip6_route.h>
 #include <net/ip6_fib.h>
-#include <net/ip6_checksum.h>
 #include <net/iucv/af_iucv.h>
 #include <linux/hashtable.h>
 
@@ -1983,21 +1982,23 @@ static int qeth_l3_get_cast_type(struct sk_buff *skb)
 	rcu_read_unlock();
 
 	/* no neighbour (eg AF_PACKET), fall back to target's IP address ... */
-	if (be16_to_cpu(skb->protocol) == ETH_P_IPV6)
-		return ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr) ?
-				RTN_MULTICAST : RTN_UNICAST;
-	else if (be16_to_cpu(skb->protocol) == ETH_P_IP)
+	switch (qeth_get_ip_version(skb)) {
+	case 4:
 		return ipv4_is_multicast(ip_hdr(skb)->daddr) ?
 				RTN_MULTICAST : RTN_UNICAST;
-
-	/* ... and MAC address */
-	if (ether_addr_equal_64bits(eth_hdr(skb)->h_dest, skb->dev->broadcast))
-		return RTN_BROADCAST;
-	if (is_multicast_ether_addr(eth_hdr(skb)->h_dest))
-		return RTN_MULTICAST;
-
-	/* default to unicast */
-	return RTN_UNICAST;
+	case 6:
+		return ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr) ?
+				RTN_MULTICAST : RTN_UNICAST;
+	default:
+		/* ... and MAC address */
+		if (ether_addr_equal_64bits(eth_hdr(skb)->h_dest,
+					    skb->dev->broadcast))
+			return RTN_BROADCAST;
+		if (is_multicast_ether_addr(eth_hdr(skb)->h_dest))
+			return RTN_MULTICAST;
+		/* default to unicast */
+		return RTN_UNICAST;
+	}
 }
 
 static void qeth_l3_fill_af_iucv_hdr(struct qeth_hdr *hdr, struct sk_buff *skb,
@@ -2006,7 +2007,6 @@ static void qeth_l3_fill_af_iucv_hdr(struct qeth_hdr *hdr, struct sk_buff *skb,
 	char daddr[16];
 	struct af_iucv_trans_hdr *iucv_hdr;
 
-	memset(hdr, 0, sizeof(struct qeth_hdr));
 	hdr->hdr.l3.id = QETH_HEADER_TYPE_LAYER3;
 	hdr->hdr.l3.length = data_len;
 	hdr->hdr.l3.flags = QETH_HDR_IPV6 | QETH_CAST_UNICAST;
@@ -2034,26 +2034,33 @@ static void qeth_l3_fill_header(struct qeth_card *card, struct qeth_hdr *hdr,
 				struct sk_buff *skb, int ipv, int cast_type,
 				unsigned int data_len)
 {
-	memset(hdr, 0, sizeof(struct qeth_hdr));
-	hdr->hdr.l3.id = QETH_HEADER_TYPE_LAYER3;
+	struct vlan_ethhdr *veth = vlan_eth_hdr(skb);
+
 	hdr->hdr.l3.length = data_len;
 
-	/*
-	 * before we're going to overwrite this location with next hop ip.
-	 * v6 uses passthrough, v4 sets the tag in the QDIO header.
-	 */
-	if (skb_vlan_tag_present(skb)) {
-		if ((ipv == 4) || (card->info.type == QETH_CARD_TYPE_IQD))
-			hdr->hdr.l3.ext_flags = QETH_HDR_EXT_VLAN_FRAME;
-		else
-			hdr->hdr.l3.ext_flags = QETH_HDR_EXT_INCLUDE_VLAN_TAG;
-		hdr->hdr.l3.vlan_id = skb_vlan_tag_get(skb);
+	if (skb_is_gso(skb)) {
+		hdr->hdr.l3.id = QETH_HEADER_TYPE_TSO;
+	} else {
+		hdr->hdr.l3.id = QETH_HEADER_TYPE_LAYER3;
+		if (skb->ip_summed == CHECKSUM_PARTIAL) {
+			qeth_tx_csum(skb, &hdr->hdr.l3.ext_flags, ipv);
+			/* some HW requires combined L3+L4 csum offload: */
+			if (ipv == 4)
+				hdr->hdr.l3.ext_flags |= QETH_HDR_EXT_CSUM_HDR_REQ;
+			if (card->options.performance_stats)
+				card->perf_stats.tx_csum++;
+		}
 	}
 
-	if (!skb_is_gso(skb) && skb->ip_summed == CHECKSUM_PARTIAL) {
-		qeth_tx_csum(skb, &hdr->hdr.l3.ext_flags, ipv);
-		if (card->options.performance_stats)
-			card->perf_stats.tx_csum++;
+	if (ipv == 4 || IS_IQD(card)) {
+		/* NETIF_F_HW_VLAN_CTAG_TX */
+		if (skb_vlan_tag_present(skb)) {
+			hdr->hdr.l3.ext_flags |= QETH_HDR_EXT_VLAN_FRAME;
+			hdr->hdr.l3.vlan_id = skb_vlan_tag_get(skb);
+		}
+	} else if (veth->h_vlan_proto == htons(ETH_P_8021Q)) {
+		hdr->hdr.l3.ext_flags |= QETH_HDR_EXT_INCLUDE_VLAN_TAG;
+		hdr->hdr.l3.vlan_id = ntohs(veth->h_vlan_TCI);
 	}
 
 	/* OSA only: */
@@ -2094,85 +2101,57 @@ static void qeth_l3_fill_header(struct qeth_card *card, struct qeth_hdr *hdr,
 	rcu_read_unlock();
 }
 
-static void qeth_tso_fill_header(struct qeth_card *card,
-		struct qeth_hdr *qhdr, struct sk_buff *skb)
+static void qeth_l3_fill_tso_ext(struct qeth_hdr_tso *hdr,
+				 unsigned int payload_len, struct sk_buff *skb,
+				 unsigned int proto_len)
 {
-	struct qeth_hdr_tso *hdr = (struct qeth_hdr_tso *)qhdr;
-	struct tcphdr *tcph = tcp_hdr(skb);
-	struct iphdr *iph = ip_hdr(skb);
-	struct ipv6hdr *ip6h = ipv6_hdr(skb);
-
-	/*fix header to TSO values ...*/
-	hdr->hdr.hdr.l3.id = QETH_HEADER_TYPE_TSO;
-	/*set values which are fix for the first approach ...*/
-	hdr->ext.hdr_tot_len = (__u16) sizeof(struct qeth_hdr_ext_tso);
-	hdr->ext.imb_hdr_no  = 1;
-	hdr->ext.hdr_type    = 1;
-	hdr->ext.hdr_version = 1;
-	hdr->ext.hdr_len     = 28;
-	/*insert non-fix values */
-	hdr->ext.mss = skb_shinfo(skb)->gso_size;
-	hdr->ext.dg_hdr_len = (__u16)(ip_hdrlen(skb) + tcp_hdrlen(skb));
-	hdr->ext.payload_len = (__u16)(skb->len - hdr->ext.dg_hdr_len -
-				       sizeof(struct qeth_hdr_tso));
-	tcph->check = 0;
-	if (be16_to_cpu(skb->protocol) == ETH_P_IPV6) {
-		ip6h->payload_len = 0;
-		tcph->check = ~csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
-					       0, IPPROTO_TCP, 0);
-	} else {
-		/*OSA want us to set these values ...*/
-		tcph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr,
-					 0, IPPROTO_TCP, 0);
-		iph->tot_len = 0;
-		iph->check = 0;
-	}
+	struct qeth_hdr_ext_tso *ext = &hdr->ext;
+
+	ext->hdr_tot_len = sizeof(*ext);
+	ext->imb_hdr_no = 1;
+	ext->hdr_type = 1;
+	ext->hdr_version = 1;
+	ext->hdr_len = 28;
+	ext->payload_len = payload_len;
+	ext->mss = skb_shinfo(skb)->gso_size;
+	ext->dg_hdr_len = proto_len;
 }
 
-/**
- * qeth_l3_get_elements_no_tso() - find number of SBALEs for skb data for tso
- * @card:			   qeth card structure, to check max. elems.
- * @skb:			   SKB address
- * @extra_elems:		   extra elems needed, to check against max.
- *
- * Returns the number of pages, and thus QDIO buffer elements, needed to cover
- * skb data, including linear part and fragments, but excluding TCP header.
- * (Exclusion of TCP header distinguishes it from qeth_get_elements_no().)
- * Checks if the result plus extra_elems fits under the limit for the card.
- * Returns 0 if it does not.
- * Note: extra_elems is not included in the returned result.
- */
-static int qeth_l3_get_elements_no_tso(struct qeth_card *card,
-			struct sk_buff *skb, int extra_elems)
+static void qeth_l3_fixup_headers(struct sk_buff *skb)
 {
-	addr_t start = (addr_t)tcp_hdr(skb) + tcp_hdrlen(skb);
-	addr_t end = (addr_t)skb->data + skb_headlen(skb);
-	int elements = qeth_get_elements_for_frags(skb);
-
-	if (start != end)
-		elements += qeth_get_elements_for_range(start, end);
+	struct iphdr *iph = ip_hdr(skb);
 
-	if ((elements + extra_elems) > QETH_MAX_BUFFER_ELEMENTS(card)) {
-		QETH_DBF_MESSAGE(2,
-	"Invalid size of TSO IP packet (Number=%d / Length=%d). Discarded.\n",
-				elements + extra_elems, skb->len);
-		return 0;
+	/* this is safe, IPv6 traffic takes a different path */
+	if (skb->ip_summed == CHECKSUM_PARTIAL)
+		iph->check = 0;
+	if (skb_is_gso(skb)) {
+		iph->tot_len = 0;
+		tcp_hdr(skb)->check = ~tcp_v4_check(0, iph->saddr,
+						    iph->daddr, 0);
 	}
-	return elements;
 }
 
-static int qeth_l3_xmit_offload(struct qeth_card *card, struct sk_buff *skb,
-				struct qeth_qdio_out_q *queue, int ipv,
-				int cast_type)
+static int qeth_l3_xmit(struct qeth_card *card, struct sk_buff *skb,
+			struct qeth_qdio_out_q *queue, int ipv, int cast_type)
 {
-	const unsigned int hw_hdr_len = sizeof(struct qeth_hdr);
-	unsigned int frame_len, elements;
+	unsigned int hw_hdr_len, proto_len, frame_len, elements;
 	unsigned char eth_hdr[ETH_HLEN];
+	bool is_tso = skb_is_gso(skb);
+	unsigned int data_offset = 0;
 	struct qeth_hdr *hdr = NULL;
 	unsigned int hd_len = 0;
 	int push_len, rc;
 	bool is_sg;
 
+	if (is_tso) {
+		hw_hdr_len = sizeof(struct qeth_hdr_tso);
+		proto_len = skb_transport_offset(skb) + tcp_hdrlen(skb) -
+			    ETH_HLEN;
+	} else {
+		hw_hdr_len = sizeof(struct qeth_hdr);
+		proto_len = 0;
+	}
+
 	/* re-use the L2 header area for the HW header: */
 	rc = skb_cow_head(skb, hw_hdr_len - ETH_HLEN);
 	if (rc)
@@ -2181,28 +2160,37 @@ static int qeth_l3_xmit_offload(struct qeth_card *card, struct sk_buff *skb,
 	skb_pull(skb, ETH_HLEN);
 	frame_len = skb->len;
 
-	push_len = qeth_add_hw_header(card, skb, &hdr, hw_hdr_len, 0,
+	qeth_l3_fixup_headers(skb);
+	push_len = qeth_add_hw_header(card, skb, &hdr, hw_hdr_len, proto_len,
 				      &elements);
 	if (push_len < 0)
 		return push_len;
-	if (!push_len) {
-		/* hdr was added discontiguous from skb->data */
-		hd_len = hw_hdr_len;
+	if (is_tso || !push_len) {
+		/* HW header needs its own buffer element. */
+		hd_len = hw_hdr_len + proto_len;
+		data_offset = push_len + proto_len;
 	}
+	memset(hdr, 0, hw_hdr_len);
 
-	if (skb->protocol == htons(ETH_P_AF_IUCV))
+	if (skb->protocol == htons(ETH_P_AF_IUCV)) {
 		qeth_l3_fill_af_iucv_hdr(hdr, skb, frame_len);
-	else
+	} else {
 		qeth_l3_fill_header(card, hdr, skb, ipv, cast_type, frame_len);
+		if (is_tso)
+			qeth_l3_fill_tso_ext((struct qeth_hdr_tso *) hdr,
+					     frame_len - proto_len, skb,
+					     proto_len);
+	}
 
 	is_sg = skb_is_nonlinear(skb);
 	if (IS_IQD(card)) {
-		rc = qeth_do_send_packet_fast(queue, skb, hdr, 0, hd_len);
+		rc = qeth_do_send_packet_fast(queue, skb, hdr, data_offset,
+					      hd_len);
 	} else {
 		/* TODO: drop skb_orphan() once TX completion is fast enough */
 		skb_orphan(skb);
-		rc = qeth_do_send_packet(card, queue, skb, hdr, 0, hd_len,
-					 elements);
+		rc = qeth_do_send_packet(card, queue, skb, hdr, data_offset,
+					 hd_len, elements);
 	}
 
 	if (!rc) {
@@ -2210,6 +2198,10 @@ static int qeth_l3_xmit_offload(struct qeth_card *card, struct sk_buff *skb,
 			card->perf_stats.buf_elements_sent += elements;
 			if (is_sg)
 				card->perf_stats.sg_skbs_sent++;
+			if (is_tso) {
+				card->perf_stats.large_send_bytes += frame_len;
+				card->perf_stats.large_send_cnt++;
+			}
 		}
 	} else {
 		if (!push_len)
@@ -2224,118 +2216,6 @@ static int qeth_l3_xmit_offload(struct qeth_card *card, struct sk_buff *skb,
 	return rc;
 }
 
-static int qeth_l3_xmit(struct qeth_card *card, struct sk_buff *skb,
-			struct qeth_qdio_out_q *queue, int ipv, int cast_type)
-{
-	int elements, len, rc;
-	__be16 *tag;
-	struct qeth_hdr *hdr = NULL;
-	int hdr_elements = 0;
-	struct sk_buff *new_skb = NULL;
-	int tx_bytes = skb->len;
-	unsigned int hd_len;
-	bool use_tso, is_sg;
-
-	/* Ignore segment size from skb_is_gso(), 1 page is always used. */
-	use_tso = skb_is_gso(skb) &&
-		  (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4);
-
-	/* create a clone with writeable headroom */
-	new_skb = skb_realloc_headroom(skb, sizeof(struct qeth_hdr_tso) +
-					    VLAN_HLEN);
-	if (!new_skb)
-		return -ENOMEM;
-
-	if (ipv == 4) {
-		skb_pull(new_skb, ETH_HLEN);
-	} else if (skb_vlan_tag_present(new_skb)) {
-		skb_push(new_skb, VLAN_HLEN);
-		skb_copy_to_linear_data(new_skb, new_skb->data + 4, 4);
-		skb_copy_to_linear_data_offset(new_skb, 4,
-					       new_skb->data + 8, 4);
-		skb_copy_to_linear_data_offset(new_skb, 8,
-					       new_skb->data + 12, 4);
-		tag = (__be16 *)(new_skb->data + 12);
-		*tag = cpu_to_be16(ETH_P_8021Q);
-		*(tag + 1) = cpu_to_be16(skb_vlan_tag_get(new_skb));
-	}
-
-	/* fix hardware limitation: as long as we do not have sbal
-	 * chaining we can not send long frag lists
-	 */
-	if ((use_tso && !qeth_l3_get_elements_no_tso(card, new_skb, 1)) ||
-	    (!use_tso && !qeth_get_elements_no(card, new_skb, 0, 0))) {
-		rc = skb_linearize(new_skb);
-
-		if (card->options.performance_stats) {
-			if (rc)
-				card->perf_stats.tx_linfail++;
-			else
-				card->perf_stats.tx_lin++;
-		}
-		if (rc)
-			goto out;
-	}
-
-	if (use_tso) {
-		hdr = skb_push(new_skb, sizeof(struct qeth_hdr_tso));
-		memset(hdr, 0, sizeof(struct qeth_hdr_tso));
-		qeth_l3_fill_header(card, hdr, new_skb, ipv, cast_type,
-				    new_skb->len - sizeof(struct qeth_hdr_tso));
-		qeth_tso_fill_header(card, hdr, new_skb);
-		hdr_elements++;
-	} else {
-		hdr = skb_push(new_skb, sizeof(struct qeth_hdr));
-		qeth_l3_fill_header(card, hdr, new_skb, ipv, cast_type,
-				    new_skb->len - sizeof(struct qeth_hdr));
-	}
-
-	elements = use_tso ?
-		   qeth_l3_get_elements_no_tso(card, new_skb, hdr_elements) :
-		   qeth_get_elements_no(card, new_skb, hdr_elements, 0);
-	if (!elements) {
-		rc = -E2BIG;
-		goto out;
-	}
-	elements += hdr_elements;
-
-	if (use_tso) {
-		hd_len = sizeof(struct qeth_hdr_tso) +
-			 ip_hdrlen(new_skb) + tcp_hdrlen(new_skb);
-		len = hd_len;
-	} else {
-		hd_len = 0;
-		len = sizeof(struct qeth_hdr_layer3);
-	}
-
-	if (qeth_hdr_chk_and_bounce(new_skb, &hdr, len)) {
-		rc = -EINVAL;
-		goto out;
-	}
-
-	is_sg = skb_is_nonlinear(new_skb);
-	rc = qeth_do_send_packet(card, queue, new_skb, hdr, hd_len, hd_len,
-				 elements);
-out:
-	if (!rc) {
-		if (new_skb != skb)
-			dev_kfree_skb_any(skb);
-		if (card->options.performance_stats) {
-			card->perf_stats.buf_elements_sent += elements;
-			if (is_sg)
-				card->perf_stats.sg_skbs_sent++;
-			if (use_tso) {
-				card->perf_stats.large_send_bytes += tx_bytes;
-				card->perf_stats.large_send_cnt++;
-			}
-		}
-	} else {
-		if (new_skb != skb)
-			dev_kfree_skb_any(new_skb);
-	}
-	return rc;
-}
-
 static netdev_tx_t qeth_l3_hard_start_xmit(struct sk_buff *skb,
 					   struct net_device *dev)
 {
@@ -2371,10 +2251,11 @@ static netdev_tx_t qeth_l3_hard_start_xmit(struct sk_buff *skb,
 	}
 	netif_stop_queue(dev);
 
-	if (IS_IQD(card) || (!skb_is_gso(skb) && ipv == 4))
-		rc = qeth_l3_xmit_offload(card, skb, queue, ipv, cast_type);
-	else
+	if (ipv == 4 || IS_IQD(card))
 		rc = qeth_l3_xmit(card, skb, queue, ipv, cast_type);
+	else
+		rc = qeth_xmit(card, skb, queue, ipv, cast_type,
+			       qeth_l3_fill_header);
 
 	if (!rc) {
 		card->stats.tx_packets++;
@@ -2412,7 +2293,10 @@ static int __qeth_l3_open(struct net_device *dev)
 
 	if (qdio_stop_irq(card->data.ccwdev, 0) >= 0) {
 		napi_enable(&card->napi);
+		local_bh_disable();
 		napi_schedule(&card->napi);
+		/* kick-start the NAPI softirq: */
+		local_bh_enable();
 	} else
 		rc = -EIO;
 	return rc;
@@ -2476,6 +2360,15 @@ qeth_l3_neigh_setup(struct net_device *dev, struct neigh_parms *np)
 	return 0;
 }
 
+static netdev_features_t qeth_l3_osa_features_check(struct sk_buff *skb,
+						    struct net_device *dev,
+						    netdev_features_t features)
+{
+	if (qeth_get_ip_version(skb) != 4)
+		features &= ~NETIF_F_HW_VLAN_CTAG_TX;
+	return qeth_features_check(skb, dev, features);
+}
+
 static const struct net_device_ops qeth_l3_netdev_ops = {
 	.ndo_open		= qeth_l3_open,
 	.ndo_stop		= qeth_l3_stop,
@@ -2496,7 +2389,7 @@ static const struct net_device_ops qeth_l3_osa_netdev_ops = {
 	.ndo_stop		= qeth_l3_stop,
 	.ndo_get_stats		= qeth_get_stats,
 	.ndo_start_xmit		= qeth_l3_hard_start_xmit,
-	.ndo_features_check	= qeth_features_check,
+	.ndo_features_check	= qeth_l3_osa_features_check,
 	.ndo_validate_addr	= eth_validate_addr,
 	.ndo_set_rx_mode	= qeth_l3_set_rx_mode,
 	.ndo_do_ioctl		= qeth_do_ioctl,
@@ -2524,6 +2417,11 @@ static int qeth_l3_setup_netdev(struct qeth_card *card)
 		}
 
 		card->dev->netdev_ops = &qeth_l3_osa_netdev_ops;
+		card->dev->needed_headroom = sizeof(struct qeth_hdr);
+		/* allow for de-acceleration of NETIF_F_HW_VLAN_CTAG_TX: */
+		card->dev->needed_headroom += VLAN_HLEN;
+		if (qeth_is_supported(card, IPA_OUTBOUND_TSO))
+			card->dev->needed_headroom = sizeof(struct qeth_hdr_tso);
 
 		/*IPv6 address autoconfiguration stuff*/
 		qeth_l3_get_unique_id(card);
@@ -2545,6 +2443,7 @@ static int qeth_l3_setup_netdev(struct qeth_card *card)
 	} else if (card->info.type == QETH_CARD_TYPE_IQD) {
 		card->dev->flags |= IFF_NOARP;
 		card->dev->netdev_ops = &qeth_l3_netdev_ops;
+		card->dev->needed_headroom = sizeof(struct qeth_hdr) - ETH_HLEN;
 
 		rc = qeth_l3_iqd_read_initial_mac(card);
 		if (rc)
@@ -2556,7 +2455,6 @@ static int qeth_l3_setup_netdev(struct qeth_card *card)
 		return -ENODEV;
 
 	card->dev->ethtool_ops = &qeth_l3_ethtool_ops;
-	card->dev->needed_headroom = sizeof(struct qeth_hdr) - ETH_HLEN;
 	card->dev->features |=	NETIF_F_HW_VLAN_CTAG_TX |
 				NETIF_F_HW_VLAN_CTAG_RX |
 				NETIF_F_HW_VLAN_CTAG_FILTER;