[deliverable/linux.git] / drivers / s390 / net / qeth_eddp.c

/*
 *
 * linux/drivers/s390/net/qeth_eddp.c ($Revision: 1.13 $)
 *
 * Enhanced Device Driver Packing (EDDP) support for the qeth driver.
 *
 * Copyright 2004 IBM Corporation
 *
 *    Author(s): Thomas Spatzier <tspat@de.ibm.com>
 *
 *    $Revision: 1.13 $	 $Date: 2005/05/04 20:19:18 $
 *
 */
#include <linux/config.h>
#include <linux/errno.h>
#include <linux/ip.h>
#include <linux/inetdevice.h>
#include <linux/netdevice.h>
#include <linux/kernel.h>
#include <linux/tcp.h>
#include <net/tcp.h>
#include <linux/skbuff.h>

#include <net/ip.h>

#include "qeth.h"
#include "qeth_mpc.h"
#include "qeth_eddp.h"

int
qeth_eddp_check_buffers_for_context(struct qeth_qdio_out_q *queue,
				    struct qeth_eddp_context *ctx)
{
	int index = queue->next_buf_to_fill;
	int elements_needed = ctx->num_elements;
	int elements_in_buffer;
	int skbs_in_buffer;
	int buffers_needed = 0;

	QETH_DBF_TEXT(trace, 5, "eddpcbfc");
	while(elements_needed > 0) {
		buffers_needed++;
		if (atomic_read(&queue->bufs[index].state) !=
				QETH_QDIO_BUF_EMPTY)
			return -EBUSY;

		elements_in_buffer = QETH_MAX_BUFFER_ELEMENTS(queue->card) -
				     queue->bufs[index].next_element_to_fill;
		skbs_in_buffer = elements_in_buffer / ctx->elements_per_skb;
		elements_needed -= skbs_in_buffer * ctx->elements_per_skb;
		index = (index + 1) % QDIO_MAX_BUFFERS_PER_Q;
	}
	return buffers_needed;
}

static inline void
qeth_eddp_free_context(struct qeth_eddp_context *ctx)
{
	int i;

	QETH_DBF_TEXT(trace, 5, "eddpfctx");
	for (i = 0; i < ctx->num_pages; ++i)
		free_page((unsigned long)ctx->pages[i]);
	kfree(ctx->pages);
	if (ctx->elements != NULL)
		kfree(ctx->elements);
	kfree(ctx);
}


static inline void
qeth_eddp_get_context(struct qeth_eddp_context *ctx)
{
	atomic_inc(&ctx->refcnt);
}

void
qeth_eddp_put_context(struct qeth_eddp_context *ctx)
{
	if (atomic_dec_return(&ctx->refcnt) == 0)
		qeth_eddp_free_context(ctx);
}

void
qeth_eddp_buf_release_contexts(struct qeth_qdio_out_buffer *buf)
{
	struct qeth_eddp_context_reference *ref;
	
	QETH_DBF_TEXT(trace, 6, "eddprctx");
	while (!list_empty(&buf->ctx_list)){
		ref = list_entry(buf->ctx_list.next,
				 struct qeth_eddp_context_reference, list);
		qeth_eddp_put_context(ref->ctx);
		list_del(&ref->list);
		kfree(ref);
	}
}

static inline int
qeth_eddp_buf_ref_context(struct qeth_qdio_out_buffer *buf,
			  struct qeth_eddp_context *ctx)
{
	struct qeth_eddp_context_reference *ref;

	QETH_DBF_TEXT(trace, 6, "eddprfcx");
	ref = kmalloc(sizeof(struct qeth_eddp_context_reference), GFP_ATOMIC);
	if (ref == NULL)
		return -ENOMEM;
	qeth_eddp_get_context(ctx);
	ref->ctx = ctx;
	list_add_tail(&ref->list, &buf->ctx_list);
	return 0;
}

int
qeth_eddp_fill_buffer(struct qeth_qdio_out_q *queue,
		      struct qeth_eddp_context *ctx,
		      int index)
{
	struct qeth_qdio_out_buffer *buf = NULL;
	struct qdio_buffer *buffer;
	int elements = ctx->num_elements;
	int element = 0;
	int flush_cnt = 0;
	int must_refcnt = 1;
	int i;

	QETH_DBF_TEXT(trace, 5, "eddpfibu");
	while (elements > 0) {
		buf = &queue->bufs[index];
		if (atomic_read(&buf->state) != QETH_QDIO_BUF_EMPTY){
			/* normally this should not happen since we checked for
			 * available elements in qeth_check_elements_for_context
			 */
			if (element == 0)
				return -EBUSY;
			else {
				PRINT_WARN("could only partially fill eddp "
					   "buffer!\n");
				goto out;
			}
		}		
		/* check if the whole next skb fits into current buffer */
		if ((QETH_MAX_BUFFER_ELEMENTS(queue->card) -
					buf->next_element_to_fill)
				< ctx->elements_per_skb){
			/* no -> go to next buffer */
			atomic_set(&buf->state, QETH_QDIO_BUF_PRIMED);
			index = (index + 1) % QDIO_MAX_BUFFERS_PER_Q;
			flush_cnt++;
			/* new buffer, so we have to add ctx to buffer'ctx_list
			 * and increment ctx's refcnt */
			must_refcnt = 1;
			continue;
		}	
		if (must_refcnt){
			must_refcnt = 0;
			if (qeth_eddp_buf_ref_context(buf, ctx)){
				PRINT_WARN("no memory to create eddp context "
					   "reference\n");
				goto out_check;
			}
		}
		buffer = buf->buffer;
		/* fill one skb into buffer */
		for (i = 0; i < ctx->elements_per_skb; ++i){
			buffer->element[buf->next_element_to_fill].addr =
				ctx->elements[element].addr;
			buffer->element[buf->next_element_to_fill].length =
				ctx->elements[element].length;
			buffer->element[buf->next_element_to_fill].flags =
				ctx->elements[element].flags;
			buf->next_element_to_fill++;
			element++;
			elements--;
		}
	}
out_check:
	if (!queue->do_pack) {
		QETH_DBF_TEXT(trace, 6, "fillbfnp");
		/* set state to PRIMED -> will be flushed */
		if (buf->next_element_to_fill > 0){
			atomic_set(&buf->state, QETH_QDIO_BUF_PRIMED);
			flush_cnt++;
		}
	} else {
#ifdef CONFIG_QETH_PERF_STATS
		queue->card->perf_stats.skbs_sent_pack++;
#endif
		QETH_DBF_TEXT(trace, 6, "fillbfpa");
		if (buf->next_element_to_fill >=
				QETH_MAX_BUFFER_ELEMENTS(queue->card)) {
			/*
			 * packed buffer if full -> set state PRIMED
			 * -> will be flushed
			 */
			atomic_set(&buf->state, QETH_QDIO_BUF_PRIMED);
			flush_cnt++;
		}
	}
out:
	return flush_cnt;
}

static inline void
qeth_eddp_create_segment_hdrs(struct qeth_eddp_context *ctx,
			      struct qeth_eddp_data *eddp, int data_len)
{
	u8 *page;
	int page_remainder;
	int page_offset;
	int pkt_len;
	struct qeth_eddp_element *element;

	QETH_DBF_TEXT(trace, 5, "eddpcrsh");
	page = ctx->pages[ctx->offset >> PAGE_SHIFT];
	page_offset = ctx->offset % PAGE_SIZE;
	element = &ctx->elements[ctx->num_elements];
	pkt_len = eddp->nhl + eddp->thl + data_len;
	/* FIXME: layer2 and VLAN !!! */
	if (eddp->qh.hdr.l2.id == QETH_HEADER_TYPE_LAYER2)
		pkt_len += ETH_HLEN;
	if (eddp->mac.h_proto == __constant_htons(ETH_P_8021Q))
		pkt_len += VLAN_HLEN;
	/* does complete packet fit in current page ? */
	page_remainder = PAGE_SIZE - page_offset;
	if (page_remainder < (sizeof(struct qeth_hdr) + pkt_len)){
		/* no -> go to start of next page */
		ctx->offset += page_remainder;
		page = ctx->pages[ctx->offset >> PAGE_SHIFT];
		page_offset = 0;
	}
	memcpy(page + page_offset, &eddp->qh, sizeof(struct qeth_hdr));
	element->addr = page + page_offset;
	element->length = sizeof(struct qeth_hdr);
	ctx->offset += sizeof(struct qeth_hdr);
	page_offset += sizeof(struct qeth_hdr);
	/* add mac header (?) */
	if (eddp->qh.hdr.l2.id == QETH_HEADER_TYPE_LAYER2){
		memcpy(page + page_offset, &eddp->mac, ETH_HLEN);
		element->length += ETH_HLEN;
		ctx->offset += ETH_HLEN;
		page_offset += ETH_HLEN;
	}
	/* add VLAN tag */
	if (eddp->mac.h_proto == __constant_htons(ETH_P_8021Q)){
		memcpy(page + page_offset, &eddp->vlan, VLAN_HLEN);
		element->length += VLAN_HLEN;
		ctx->offset += VLAN_HLEN;
		page_offset += VLAN_HLEN;
	}
	/* add network header */
	memcpy(page + page_offset, (u8 *)&eddp->nh, eddp->nhl);
	element->length += eddp->nhl;
	eddp->nh_in_ctx = page + page_offset;
	ctx->offset += eddp->nhl;
	page_offset += eddp->nhl;
	/* add transport header */
	memcpy(page + page_offset, (u8 *)&eddp->th, eddp->thl);
	element->length += eddp->thl;
	eddp->th_in_ctx = page + page_offset;
	ctx->offset += eddp->thl;
}

static inline void
qeth_eddp_copy_data_tcp(char *dst, struct qeth_eddp_data *eddp, int len,
			u32 *hcsum)
{
	struct skb_frag_struct *frag;
	int left_in_frag;
	int copy_len;
	u8 *src;
	
	QETH_DBF_TEXT(trace, 5, "eddpcdtc");
	if (skb_shinfo(eddp->skb)->nr_frags == 0) {
		memcpy(dst, eddp->skb->data + eddp->skb_offset, len);
		*hcsum = csum_partial(eddp->skb->data + eddp->skb_offset, len,
				      *hcsum);
		eddp->skb_offset += len;
	} else {
		while (len > 0) {
			if (eddp->frag < 0) {
				/* we're in skb->data */
				left_in_frag = (eddp->skb->len - eddp->skb->data_len)
						- eddp->skb_offset;
				src = eddp->skb->data + eddp->skb_offset;
			} else {
				frag = &skb_shinfo(eddp->skb)->
					frags[eddp->frag];
				left_in_frag = frag->size - eddp->frag_offset;
				src = (u8 *)(
					(page_to_pfn(frag->page) << PAGE_SHIFT)+
					frag->page_offset + eddp->frag_offset);
			}
			if (left_in_frag <= 0) {
				eddp->frag++;
				eddp->frag_offset = 0;
				continue;
			}
			copy_len = min(left_in_frag, len);
			memcpy(dst, src, copy_len);
			*hcsum = csum_partial(src, copy_len, *hcsum);
			dst += copy_len;
			eddp->frag_offset += copy_len;
			eddp->skb_offset += copy_len;
			len -= copy_len;
		}
	}
}

static inline void
qeth_eddp_create_segment_data_tcp(struct qeth_eddp_context *ctx,
				  struct qeth_eddp_data *eddp, int data_len,
				  u32 hcsum)
{
	u8 *page;
	int page_remainder;
	int page_offset;
	struct qeth_eddp_element *element;
	int first_lap = 1;

	QETH_DBF_TEXT(trace, 5, "eddpcsdt");
	page = ctx->pages[ctx->offset >> PAGE_SHIFT];
	page_offset = ctx->offset % PAGE_SIZE;
	element = &ctx->elements[ctx->num_elements];
	while (data_len){
		page_remainder = PAGE_SIZE - page_offset;
		if (page_remainder < data_len){
			qeth_eddp_copy_data_tcp(page + page_offset, eddp,
						page_remainder, &hcsum);
			element->length += page_remainder;
			if (first_lap)
				element->flags = SBAL_FLAGS_FIRST_FRAG;
			else
				element->flags = SBAL_FLAGS_MIDDLE_FRAG;
			ctx->num_elements++;
			element++;
			data_len -= page_remainder;
			ctx->offset += page_remainder;
			page = ctx->pages[ctx->offset >> PAGE_SHIFT];
			page_offset = 0;
			element->addr = page + page_offset;
		} else {
			qeth_eddp_copy_data_tcp(page + page_offset, eddp,
						data_len, &hcsum);
			element->length += data_len;
			if (!first_lap)
				element->flags = SBAL_FLAGS_LAST_FRAG;
			ctx->num_elements++;
			ctx->offset += data_len;
			data_len = 0;
		}
		first_lap = 0;
	}
	((struct tcphdr *)eddp->th_in_ctx)->check = csum_fold(hcsum);
}

static inline u32
qeth_eddp_check_tcp4_hdr(struct qeth_eddp_data *eddp, int data_len)
{
	u32 phcsum; /* pseudo header checksum */

	QETH_DBF_TEXT(trace, 5, "eddpckt4");
	eddp->th.tcp.h.check = 0;
	/* compute pseudo header checksum */
	phcsum = csum_tcpudp_nofold(eddp->nh.ip4.h.saddr, eddp->nh.ip4.h.daddr,
				    eddp->thl + data_len, IPPROTO_TCP, 0);
	/* compute checksum of tcp header */
	return csum_partial((u8 *)&eddp->th, eddp->thl, phcsum);
}

static inline u32
qeth_eddp_check_tcp6_hdr(struct qeth_eddp_data *eddp, int data_len)
{
	u32 proto;
	u32 phcsum; /* pseudo header checksum */

	QETH_DBF_TEXT(trace, 5, "eddpckt6");
	eddp->th.tcp.h.check = 0;
	/* compute pseudo header checksum */
	phcsum = csum_partial((u8 *)&eddp->nh.ip6.h.saddr,
			      sizeof(struct in6_addr), 0);
	phcsum = csum_partial((u8 *)&eddp->nh.ip6.h.daddr,
			      sizeof(struct in6_addr), phcsum);
	proto = htonl(IPPROTO_TCP);
	phcsum = csum_partial((u8 *)&proto, sizeof(u32), phcsum);
	return phcsum;
}

static inline struct qeth_eddp_data *
qeth_eddp_create_eddp_data(struct qeth_hdr *qh, u8 *nh, u8 nhl, u8 *th, u8 thl)
{
	struct qeth_eddp_data *eddp;

	QETH_DBF_TEXT(trace, 5, "eddpcrda");
	eddp = kmalloc(sizeof(struct qeth_eddp_data), GFP_ATOMIC);
	if (eddp){
		memset(eddp, 0, sizeof(struct qeth_eddp_data));
		eddp->nhl = nhl;
		eddp->thl = thl;
		memcpy(&eddp->qh, qh, sizeof(struct qeth_hdr));
		memcpy(&eddp->nh, nh, nhl);
		memcpy(&eddp->th, th, thl);
		eddp->frag = -1; /* initially we're in skb->data */
	}
	return eddp;
}

static inline void
__qeth_eddp_fill_context_tcp(struct qeth_eddp_context *ctx,
			     struct qeth_eddp_data *eddp)
{
	struct tcphdr *tcph;
	int data_len;
	u32 hcsum;
	
	QETH_DBF_TEXT(trace, 5, "eddpftcp");
	eddp->skb_offset = sizeof(struct qeth_hdr) + eddp->nhl + eddp->thl;
	tcph = eddp->skb->h.th;
	while (eddp->skb_offset < eddp->skb->len) {
		data_len = min((int)skb_shinfo(eddp->skb)->tso_size,
			       (int)(eddp->skb->len - eddp->skb_offset));
		/* prepare qdio hdr */
		if (eddp->qh.hdr.l2.id == QETH_HEADER_TYPE_LAYER2){
			eddp->qh.hdr.l2.pkt_length = data_len + ETH_HLEN +
						     eddp->nhl + eddp->thl -
						     sizeof(struct qeth_hdr);
#ifdef CONFIG_QETH_VLAN
			if (eddp->mac.h_proto == __constant_htons(ETH_P_8021Q))
				eddp->qh.hdr.l2.pkt_length += VLAN_HLEN;
#endif /* CONFIG_QETH_VLAN */
		} else
			eddp->qh.hdr.l3.length = data_len + eddp->nhl +
						 eddp->thl;
		/* prepare ip hdr */
		if (eddp->skb->protocol == ETH_P_IP){
			eddp->nh.ip4.h.tot_len = data_len + eddp->nhl +
						 eddp->thl;
			eddp->nh.ip4.h.check = 0;
			eddp->nh.ip4.h.check =
				ip_fast_csum((u8 *)&eddp->nh.ip4.h,
						eddp->nh.ip4.h.ihl);
		} else
			eddp->nh.ip6.h.payload_len = data_len + eddp->thl;
		/* prepare tcp hdr */
		if (data_len == (eddp->skb->len - eddp->skb_offset)){
			/* last segment -> set FIN and PSH flags */
			eddp->th.tcp.h.fin = tcph->fin;
			eddp->th.tcp.h.psh = tcph->psh;
		}
		if (eddp->skb->protocol == ETH_P_IP)
			hcsum = qeth_eddp_check_tcp4_hdr(eddp, data_len);
		else
			hcsum = qeth_eddp_check_tcp6_hdr(eddp, data_len);
		/* fill the next segment into the context */
		qeth_eddp_create_segment_hdrs(ctx, eddp, data_len);
		qeth_eddp_create_segment_data_tcp(ctx, eddp, data_len, hcsum);
		if (eddp->skb_offset >= eddp->skb->len)
			break;
		/* prepare headers for next round */
		if (eddp->skb->protocol == ETH_P_IP)
			eddp->nh.ip4.h.id++;
		eddp->th.tcp.h.seq += data_len;
	}
}
			   
static inline int
qeth_eddp_fill_context_tcp(struct qeth_eddp_context *ctx,
			   struct sk_buff *skb, struct qeth_hdr *qhdr)
{
	struct qeth_eddp_data *eddp = NULL;
	
	QETH_DBF_TEXT(trace, 5, "eddpficx");
	/* create our segmentation headers and copy original headers */
	if (skb->protocol == ETH_P_IP)
		eddp = qeth_eddp_create_eddp_data(qhdr, (u8 *)skb->nh.iph,
				skb->nh.iph->ihl*4,
				(u8 *)skb->h.th, skb->h.th->doff*4);
	else
		eddp = qeth_eddp_create_eddp_data(qhdr, (u8 *)skb->nh.ipv6h,
				sizeof(struct ipv6hdr),
				(u8 *)skb->h.th, skb->h.th->doff*4);

	if (eddp == NULL) {
		QETH_DBF_TEXT(trace, 2, "eddpfcnm");
		return -ENOMEM;
	}
	if (qhdr->hdr.l2.id == QETH_HEADER_TYPE_LAYER2) {
		memcpy(&eddp->mac, eth_hdr(skb), ETH_HLEN);
#ifdef CONFIG_QETH_VLAN
		if (eddp->mac.h_proto == __constant_htons(ETH_P_8021Q)) {
			eddp->vlan[0] = __constant_htons(skb->protocol);
			eddp->vlan[1] = htons(vlan_tx_tag_get(skb));
		}
#endif /* CONFIG_QETH_VLAN */
	}
	/* the next flags will only be set on the last segment */
	eddp->th.tcp.h.fin = 0;
	eddp->th.tcp.h.psh = 0;
	eddp->skb = skb;
	/* begin segmentation and fill context */
	__qeth_eddp_fill_context_tcp(ctx, eddp);
	kfree(eddp);
	return 0;
}

static inline void
qeth_eddp_calc_num_pages(struct qeth_eddp_context *ctx, struct sk_buff *skb,
			 int hdr_len)
{
	int skbs_per_page;
	
	QETH_DBF_TEXT(trace, 5, "eddpcanp");
	/* can we put multiple skbs in one page? */
	skbs_per_page = PAGE_SIZE / (skb_shinfo(skb)->tso_size + hdr_len);
	if (skbs_per_page > 1){
		ctx->num_pages = (skb_shinfo(skb)->tso_segs + 1) /
				 skbs_per_page + 1;
		ctx->elements_per_skb = 1;
	} else {
		/* no -> how many elements per skb? */
		ctx->elements_per_skb = (skb_shinfo(skb)->tso_size + hdr_len +
				     PAGE_SIZE) >> PAGE_SHIFT;
		ctx->num_pages = ctx->elements_per_skb *
				 (skb_shinfo(skb)->tso_segs + 1);
	}
	ctx->num_elements = ctx->elements_per_skb *
			    (skb_shinfo(skb)->tso_segs + 1);
}

static inline struct qeth_eddp_context *
qeth_eddp_create_context_generic(struct qeth_card *card, struct sk_buff *skb,
				 int hdr_len)
{
	struct qeth_eddp_context *ctx = NULL;
	u8 *addr;
	int i;

	QETH_DBF_TEXT(trace, 5, "creddpcg");
	/* create the context and allocate pages */
	ctx = kmalloc(sizeof(struct qeth_eddp_context), GFP_ATOMIC);
	if (ctx == NULL){
		QETH_DBF_TEXT(trace, 2, "ceddpcn1");
		return NULL;
	}
	memset(ctx, 0, sizeof(struct qeth_eddp_context));
	ctx->type = QETH_LARGE_SEND_EDDP;
	qeth_eddp_calc_num_pages(ctx, skb, hdr_len);
	if (ctx->elements_per_skb > QETH_MAX_BUFFER_ELEMENTS(card)){
		QETH_DBF_TEXT(trace, 2, "ceddpcis");
		kfree(ctx);
		return NULL;
	}
	ctx->pages = kmalloc(ctx->num_pages * sizeof(u8 *), GFP_ATOMIC);
	if (ctx->pages == NULL){
		QETH_DBF_TEXT(trace, 2, "ceddpcn2");
		kfree(ctx);
		return NULL;
	}
	memset(ctx->pages, 0, ctx->num_pages * sizeof(u8 *));
	for (i = 0; i < ctx->num_pages; ++i){
		addr = (u8 *)__get_free_page(GFP_ATOMIC);
		if (addr == NULL){
			QETH_DBF_TEXT(trace, 2, "ceddpcn3");
			ctx->num_pages = i;
			qeth_eddp_free_context(ctx);
			return NULL;
		}
		memset(addr, 0, PAGE_SIZE);
		ctx->pages[i] = addr;
	}
	ctx->elements = kmalloc(ctx->num_elements *
				sizeof(struct qeth_eddp_element), GFP_ATOMIC);
	if (ctx->elements == NULL){
		QETH_DBF_TEXT(trace, 2, "ceddpcn4");
		qeth_eddp_free_context(ctx);
		return NULL;
	}
	memset(ctx->elements, 0,
	       ctx->num_elements * sizeof(struct qeth_eddp_element));
	/* reset num_elements; will be incremented again in fill_buffer to
	 * reflect number of actually used elements */
	ctx->num_elements = 0;
	return ctx;
}

static inline struct qeth_eddp_context *
qeth_eddp_create_context_tcp(struct qeth_card *card, struct sk_buff *skb,
			     struct qeth_hdr *qhdr)
{
	struct qeth_eddp_context *ctx = NULL;
	
	QETH_DBF_TEXT(trace, 5, "creddpct");
	if (skb->protocol == ETH_P_IP)
		ctx = qeth_eddp_create_context_generic(card, skb,
			sizeof(struct qeth_hdr) + skb->nh.iph->ihl*4 +
			skb->h.th->doff*4);
	else if (skb->protocol == ETH_P_IPV6)
		ctx = qeth_eddp_create_context_generic(card, skb,
			sizeof(struct qeth_hdr) + sizeof(struct ipv6hdr) +
			skb->h.th->doff*4);
	else
		QETH_DBF_TEXT(trace, 2, "cetcpinv");

	if (ctx == NULL) {
		QETH_DBF_TEXT(trace, 2, "creddpnl");
		return NULL;
	}
	if (qeth_eddp_fill_context_tcp(ctx, skb, qhdr)){
		QETH_DBF_TEXT(trace, 2, "ceddptfe");
		qeth_eddp_free_context(ctx);
		return NULL;
	}
	atomic_set(&ctx->refcnt, 1);
	return ctx;
}

struct qeth_eddp_context *
qeth_eddp_create_context(struct qeth_card *card, struct sk_buff *skb,
			 struct qeth_hdr *qhdr)
{
	QETH_DBF_TEXT(trace, 5, "creddpc");
	switch (skb->sk->sk_protocol){
	case IPPROTO_TCP:
		return qeth_eddp_create_context_tcp(card, skb, qhdr);
	default:
		QETH_DBF_TEXT(trace, 2, "eddpinvp");
	}
	return NULL;
}
Commit	Line	Data
1da177e4 LT	1	/*
1da177e4 LT	2	*
05e08a2a	3	* linux/drivers/s390/net/qeth_eddp.c ($Revision: 1.13 $)
1da177e4 LT	4	*
	5	* Enhanced Device Driver Packing (EDDP) support for the qeth driver.
	6	*
	7	* Copyright 2004 IBM Corporation
	8	*
	9	* Author(s): Thomas Spatzier <tspat@de.ibm.com>
	10	*
05e08a2a	11	* $Revision: 1.13 $ $Date: 2005/05/04 20:19:18 $
1da177e4 LT	12	*
	13	*/
	14	#include <linux/config.h>
	15	#include <linux/errno.h>
	16	#include <linux/ip.h>
	17	#include <linux/inetdevice.h>
	18	#include <linux/netdevice.h>
	19	#include <linux/kernel.h>
	20	#include <linux/tcp.h>
	21	#include <net/tcp.h>
	22	#include <linux/skbuff.h>
	23
	24	#include <net/ip.h>
	25
	26	#include "qeth.h"
	27	#include "qeth_mpc.h"
	28	#include "qeth_eddp.h"
	29
	30	int
	31	qeth_eddp_check_buffers_for_context(struct qeth_qdio_out_q *queue,
	32	struct qeth_eddp_context *ctx)
	33	{
	34	int index = queue->next_buf_to_fill;
	35	int elements_needed = ctx->num_elements;
	36	int elements_in_buffer;
	37	int skbs_in_buffer;
	38	int buffers_needed = 0;
	39
	40	QETH_DBF_TEXT(trace, 5, "eddpcbfc");
	41	while(elements_needed > 0) {
	42	buffers_needed++;
	43	if (atomic_read(&queue->bufs[index].state) !=
	44	QETH_QDIO_BUF_EMPTY)
	45	return -EBUSY;
	46
	47	elements_in_buffer = QETH_MAX_BUFFER_ELEMENTS(queue->card) -
	48	queue->bufs[index].next_element_to_fill;
	49	skbs_in_buffer = elements_in_buffer / ctx->elements_per_skb;
	50	elements_needed -= skbs_in_buffer * ctx->elements_per_skb;
	51	index = (index + 1) % QDIO_MAX_BUFFERS_PER_Q;
	52	}
	53	return buffers_needed;
	54	}
	55
	56	static inline void
	57	qeth_eddp_free_context(struct qeth_eddp_context *ctx)
	58	{
	59	int i;
	60
	61	QETH_DBF_TEXT(trace, 5, "eddpfctx");
	62	for (i = 0; i < ctx->num_pages; ++i)
	63	free_page((unsigned long)ctx->pages[i]);
	64	kfree(ctx->pages);
4965e97f FP	65	if (ctx->elements != NULL)
4965e97f FP	66	kfree(ctx->elements);
1da177e4 LT	67	kfree(ctx);
	68	}
	69
	70
	71	static inline void
	72	qeth_eddp_get_context(struct qeth_eddp_context *ctx)
	73	{
	74	atomic_inc(&ctx->refcnt);
	75	}
	76
	77	void
	78	qeth_eddp_put_context(struct qeth_eddp_context *ctx)
	79	{
	80	if (atomic_dec_return(&ctx->refcnt) == 0)
	81	qeth_eddp_free_context(ctx);
	82	}
	83
	84	void
	85	qeth_eddp_buf_release_contexts(struct qeth_qdio_out_buffer *buf)
	86	{
	87	struct qeth_eddp_context_reference *ref;
05e08a2a	88
1da177e4 LT	89	QETH_DBF_TEXT(trace, 6, "eddprctx");
	90	while (!list_empty(&buf->ctx_list)){
	91	ref = list_entry(buf->ctx_list.next,
	92	struct qeth_eddp_context_reference, list);
	93	qeth_eddp_put_context(ref->ctx);
	94	list_del(&ref->list);
	95	kfree(ref);
	96	}
	97	}
	98
	99	static inline int
	100	qeth_eddp_buf_ref_context(struct qeth_qdio_out_buffer *buf,
	101	struct qeth_eddp_context *ctx)
	102	{
	103	struct qeth_eddp_context_reference *ref;
	104
	105	QETH_DBF_TEXT(trace, 6, "eddprfcx");
	106	ref = kmalloc(sizeof(struct qeth_eddp_context_reference), GFP_ATOMIC);
	107	if (ref == NULL)
	108	return -ENOMEM;
	109	qeth_eddp_get_context(ctx);
	110	ref->ctx = ctx;
	111	list_add_tail(&ref->list, &buf->ctx_list);
	112	return 0;
	113	}
	114
	115	int
	116	qeth_eddp_fill_buffer(struct qeth_qdio_out_q *queue,
	117	struct qeth_eddp_context *ctx,
	118	int index)
	119	{
	120	struct qeth_qdio_out_buffer *buf = NULL;
	121	struct qdio_buffer *buffer;
	122	int elements = ctx->num_elements;
	123	int element = 0;
	124	int flush_cnt = 0;
	125	int must_refcnt = 1;
	126	int i;
	127
	128	QETH_DBF_TEXT(trace, 5, "eddpfibu");
	129	while (elements > 0) {
	130	buf = &queue->bufs[index];
	131	if (atomic_read(&buf->state) != QETH_QDIO_BUF_EMPTY){
	132	/* normally this should not happen since we checked for
	133	* available elements in qeth_check_elements_for_context
	134	*/
	135	if (element == 0)
	136	return -EBUSY;
	137	else {
	138	PRINT_WARN("could only partially fill eddp "
	139	"buffer!\n");
	140	goto out;
	141	}
05e08a2a	142	}
1da177e4 LT	143	/* check if the whole next skb fits into current buffer */
	144	if ((QETH_MAX_BUFFER_ELEMENTS(queue->card) -
	145	buf->next_element_to_fill)
	146	< ctx->elements_per_skb){
	147	/* no -> go to next buffer */
	148	atomic_set(&buf->state, QETH_QDIO_BUF_PRIMED);
	149	index = (index + 1) % QDIO_MAX_BUFFERS_PER_Q;
	150	flush_cnt++;
	151	/* new buffer, so we have to add ctx to buffer'ctx_list
	152	* and increment ctx's refcnt */
	153	must_refcnt = 1;
	154	continue;
05e08a2a	155	}
1da177e4 LT	156	if (must_refcnt){
	157	must_refcnt = 0;
	158	if (qeth_eddp_buf_ref_context(buf, ctx)){
	159	PRINT_WARN("no memory to create eddp context "
	160	"reference\n");
	161	goto out_check;
	162	}
	163	}
	164	buffer = buf->buffer;
	165	/* fill one skb into buffer */
	166	for (i = 0; i < ctx->elements_per_skb; ++i){
	167	buffer->element[buf->next_element_to_fill].addr =
	168	ctx->elements[element].addr;
	169	buffer->element[buf->next_element_to_fill].length =
	170	ctx->elements[element].length;
	171	buffer->element[buf->next_element_to_fill].flags =
	172	ctx->elements[element].flags;
	173	buf->next_element_to_fill++;
	174	element++;
	175	elements--;
	176	}
	177	}
	178	out_check:
	179	if (!queue->do_pack) {
	180	QETH_DBF_TEXT(trace, 6, "fillbfnp");
	181	/* set state to PRIMED -> will be flushed */
	182	if (buf->next_element_to_fill > 0){
	183	atomic_set(&buf->state, QETH_QDIO_BUF_PRIMED);
	184	flush_cnt++;
	185	}
	186	} else {
	187	#ifdef CONFIG_QETH_PERF_STATS
	188	queue->card->perf_stats.skbs_sent_pack++;
	189	#endif
	190	QETH_DBF_TEXT(trace, 6, "fillbfpa");
	191	if (buf->next_element_to_fill >=
	192	QETH_MAX_BUFFER_ELEMENTS(queue->card)) {
	193	/*
	194	* packed buffer if full -> set state PRIMED
	195	* -> will be flushed
	196	*/
	197	atomic_set(&buf->state, QETH_QDIO_BUF_PRIMED);
	198	flush_cnt++;
	199	}
	200	}
	201	out:
	202	return flush_cnt;
	203	}
	204
1da177e4 LT	205	static inline void
1da177e4 LT	206	qeth_eddp_create_segment_hdrs(struct qeth_eddp_context *ctx,
05e08a2a	207	struct qeth_eddp_data *eddp, int data_len)
1da177e4 LT	208	{
	209	u8 *page;
	210	int page_remainder;
	211	int page_offset;
05e08a2a	212	int pkt_len;
1da177e4 LT	213	struct qeth_eddp_element *element;
	214
	215	QETH_DBF_TEXT(trace, 5, "eddpcrsh");
	216	page = ctx->pages[ctx->offset >> PAGE_SHIFT];
	217	page_offset = ctx->offset % PAGE_SIZE;
	218	element = &ctx->elements[ctx->num_elements];
05e08a2a	219	pkt_len = eddp->nhl + eddp->thl + data_len;
1da177e4 LT	220	/* FIXME: layer2 and VLAN !!! */
1da177e4 LT	221	if (eddp->qh.hdr.l2.id == QETH_HEADER_TYPE_LAYER2)
05e08a2a	222	pkt_len += ETH_HLEN;
1da177e4	223	if (eddp->mac.h_proto == __constant_htons(ETH_P_8021Q))
05e08a2a FP	224	pkt_len += VLAN_HLEN;
05e08a2a FP	225	/* does complete packet fit in current page ? */
1da177e4	226	page_remainder = PAGE_SIZE - page_offset;
05e08a2a	227	if (page_remainder < (sizeof(struct qeth_hdr) + pkt_len)){
1da177e4 LT	228	/* no -> go to start of next page */
	229	ctx->offset += page_remainder;
	230	page = ctx->pages[ctx->offset >> PAGE_SHIFT];
	231	page_offset = 0;
	232	}
	233	memcpy(page + page_offset, &eddp->qh, sizeof(struct qeth_hdr));
	234	element->addr = page + page_offset;
	235	element->length = sizeof(struct qeth_hdr);
	236	ctx->offset += sizeof(struct qeth_hdr);
	237	page_offset += sizeof(struct qeth_hdr);
	238	/* add mac header (?) */
	239	if (eddp->qh.hdr.l2.id == QETH_HEADER_TYPE_LAYER2){
	240	memcpy(page + page_offset, &eddp->mac, ETH_HLEN);
	241	element->length += ETH_HLEN;
	242	ctx->offset += ETH_HLEN;
	243	page_offset += ETH_HLEN;
	244	}
	245	/* add VLAN tag */
	246	if (eddp->mac.h_proto == __constant_htons(ETH_P_8021Q)){
	247	memcpy(page + page_offset, &eddp->vlan, VLAN_HLEN);
	248	element->length += VLAN_HLEN;
	249	ctx->offset += VLAN_HLEN;
	250	page_offset += VLAN_HLEN;
	251	}
	252	/* add network header */
	253	memcpy(page + page_offset, (u8 *)&eddp->nh, eddp->nhl);
	254	element->length += eddp->nhl;
	255	eddp->nh_in_ctx = page + page_offset;
	256	ctx->offset += eddp->nhl;
	257	page_offset += eddp->nhl;
	258	/* add transport header */
	259	memcpy(page + page_offset, (u8 *)&eddp->th, eddp->thl);
	260	element->length += eddp->thl;
	261	eddp->th_in_ctx = page + page_offset;
	262	ctx->offset += eddp->thl;
	263	}
	264
	265	static inline void
	266	qeth_eddp_copy_data_tcp(char dst, struct qeth_eddp_data eddp, int len,
	267	u32 *hcsum)
	268	{
	269	struct skb_frag_struct *frag;
	270	int left_in_frag;
	271	int copy_len;
	272	u8 *src;
05e08a2a	273
1da177e4 LT	274	QETH_DBF_TEXT(trace, 5, "eddpcdtc");
	275	if (skb_shinfo(eddp->skb)->nr_frags == 0) {
	276	memcpy(dst, eddp->skb->data + eddp->skb_offset, len);
	277	*hcsum = csum_partial(eddp->skb->data + eddp->skb_offset, len,
	278	*hcsum);
	279	eddp->skb_offset += len;
	280	} else {
	281	while (len > 0) {
	282	if (eddp->frag < 0) {
	283	/* we're in skb->data */
05e08a2a	284	left_in_frag = (eddp->skb->len - eddp->skb->data_len)
1da177e4 LT	285	- eddp->skb_offset;
	286	src = eddp->skb->data + eddp->skb_offset;
	287	} else {
	288	frag = &skb_shinfo(eddp->skb)->
	289	frags[eddp->frag];
	290	left_in_frag = frag->size - eddp->frag_offset;
	291	src = (u8 *)(
	292	(page_to_pfn(frag->page) << PAGE_SHIFT)+
	293	frag->page_offset + eddp->frag_offset);
	294	}
	295	if (left_in_frag <= 0) {
	296	eddp->frag++;
	297	eddp->frag_offset = 0;
	298	continue;
	299	}
	300	copy_len = min(left_in_frag, len);
	301	memcpy(dst, src, copy_len);
	302	hcsum = csum_partial(src, copy_len, hcsum);
	303	dst += copy_len;
	304	eddp->frag_offset += copy_len;
	305	eddp->skb_offset += copy_len;
	306	len -= copy_len;
	307	}
	308	}
	309	}
	310
	311	static inline void
	312	qeth_eddp_create_segment_data_tcp(struct qeth_eddp_context *ctx,
	313	struct qeth_eddp_data *eddp, int data_len,
	314	u32 hcsum)
	315	{
	316	u8 *page;
	317	int page_remainder;
	318	int page_offset;
	319	struct qeth_eddp_element *element;
	320	int first_lap = 1;
	321
	322	QETH_DBF_TEXT(trace, 5, "eddpcsdt");
	323	page = ctx->pages[ctx->offset >> PAGE_SHIFT];
	324	page_offset = ctx->offset % PAGE_SIZE;
	325	element = &ctx->elements[ctx->num_elements];
	326	while (data_len){
	327	page_remainder = PAGE_SIZE - page_offset;
	328	if (page_remainder < data_len){
	329	qeth_eddp_copy_data_tcp(page + page_offset, eddp,
	330	page_remainder, &hcsum);
	331	element->length += page_remainder;
	332	if (first_lap)
	333	element->flags = SBAL_FLAGS_FIRST_FRAG;
	334	else
	335	element->flags = SBAL_FLAGS_MIDDLE_FRAG;
	336	ctx->num_elements++;
	337	element++;
	338	data_len -= page_remainder;
	339	ctx->offset += page_remainder;
	340	page = ctx->pages[ctx->offset >> PAGE_SHIFT];
	341	page_offset = 0;
	342	element->addr = page + page_offset;
	343	} else {
	344	qeth_eddp_copy_data_tcp(page + page_offset, eddp,
	345	data_len, &hcsum);
	346	element->length += data_len;
	347	if (!first_lap)
	348	element->flags = SBAL_FLAGS_LAST_FRAG;
349	ctx->num_elements++;
350	ctx->offset += data_len;
351	data_len = 0;
352	}
353	first_lap = 0;
354	}
355	((struct tcphdr *)eddp->th_in_ctx)->check = csum_fold(hcsum);
356	}
357
358	static inline u32
359	qeth_eddp_check_tcp4_hdr(struct qeth_eddp_data *eddp, int data_len)
360	{
361	u32 phcsum; /* pseudo header checksum */
362
363	QETH_DBF_TEXT(trace, 5, "eddpckt4");
364	eddp->th.tcp.h.check = 0;
365	/* compute pseudo header checksum */
366	phcsum = csum_tcpudp_nofold(eddp->nh.ip4.h.saddr, eddp->nh.ip4.h.daddr,
367	eddp->thl + data_len, IPPROTO_TCP, 0);
368	/* compute checksum of tcp header */
369	return csum_partial((u8 *)&eddp->th, eddp->thl, phcsum);
370	}
371
372	static inline u32
373	qeth_eddp_check_tcp6_hdr(struct qeth_eddp_data *eddp, int data_len)
374	{
375	u32 proto;
376	u32 phcsum; /* pseudo header checksum */
377
378	QETH_DBF_TEXT(trace, 5, "eddpckt6");
379	eddp->th.tcp.h.check = 0;
380	/* compute pseudo header checksum */
381	phcsum = csum_partial((u8 *)&eddp->nh.ip6.h.saddr,
382	sizeof(struct in6_addr), 0);
383	phcsum = csum_partial((u8 *)&eddp->nh.ip6.h.daddr,
384	sizeof(struct in6_addr), phcsum);
385	proto = htonl(IPPROTO_TCP);
386	phcsum = csum_partial((u8 *)&proto, sizeof(u32), phcsum);
387	return phcsum;
388	}
389
390	static inline struct qeth_eddp_data *
391	qeth_eddp_create_eddp_data(struct qeth_hdr qh, u8 nh, u8 nhl, u8 *th, u8 thl)
392	{
393	struct qeth_eddp_data *eddp;
394
395	QETH_DBF_TEXT(trace, 5, "eddpcrda");
396	eddp = kmalloc(sizeof(struct qeth_eddp_data), GFP_ATOMIC);
397	if (eddp){
398	memset(eddp, 0, sizeof(struct qeth_eddp_data));
399	eddp->nhl = nhl;
400	eddp->thl = thl;
401	memcpy(&eddp->qh, qh, sizeof(struct qeth_hdr));
402	memcpy(&eddp->nh, nh, nhl);
403	memcpy(&eddp->th, th, thl);
404	eddp->frag = -1; /* initially we're in skb->data */
405	}
406	return eddp;
407	}
408
409	static inline void
410	__qeth_eddp_fill_context_tcp(struct qeth_eddp_context *ctx,
411	struct qeth_eddp_data *eddp)
412	{
413	struct tcphdr *tcph;
414	int data_len;
415	u32 hcsum;
05e08a2a	416
1da177e4 LT	417	QETH_DBF_TEXT(trace, 5, "eddpftcp");
	418	eddp->skb_offset = sizeof(struct qeth_hdr) + eddp->nhl + eddp->thl;
	419	tcph = eddp->skb->h.th;
	420	while (eddp->skb_offset < eddp->skb->len) {
	421	data_len = min((int)skb_shinfo(eddp->skb)->tso_size,
	422	(int)(eddp->skb->len - eddp->skb_offset));
	423	/* prepare qdio hdr */
	424	if (eddp->qh.hdr.l2.id == QETH_HEADER_TYPE_LAYER2){
	425	eddp->qh.hdr.l2.pkt_length = data_len + ETH_HLEN +
	426	eddp->nhl + eddp->thl -
	427	sizeof(struct qeth_hdr);
	428	#ifdef CONFIG_QETH_VLAN
	429	if (eddp->mac.h_proto == __constant_htons(ETH_P_8021Q))
	430	eddp->qh.hdr.l2.pkt_length += VLAN_HLEN;
	431	#endif /* CONFIG_QETH_VLAN */
	432	} else
	433	eddp->qh.hdr.l3.length = data_len + eddp->nhl +
	434	eddp->thl;
	435	/* prepare ip hdr */
	436	if (eddp->skb->protocol == ETH_P_IP){
	437	eddp->nh.ip4.h.tot_len = data_len + eddp->nhl +
	438	eddp->thl;
	439	eddp->nh.ip4.h.check = 0;
	440	eddp->nh.ip4.h.check =
	441	ip_fast_csum((u8 *)&eddp->nh.ip4.h,
	442	eddp->nh.ip4.h.ihl);
	443	} else
	444	eddp->nh.ip6.h.payload_len = data_len + eddp->thl;
	445	/* prepare tcp hdr */
	446	if (data_len == (eddp->skb->len - eddp->skb_offset)){
	447	/* last segment -> set FIN and PSH flags */
	448	eddp->th.tcp.h.fin = tcph->fin;
	449	eddp->th.tcp.h.psh = tcph->psh;
	450	}
	451	if (eddp->skb->protocol == ETH_P_IP)
	452	hcsum = qeth_eddp_check_tcp4_hdr(eddp, data_len);
	453	else
	454	hcsum = qeth_eddp_check_tcp6_hdr(eddp, data_len);
	455	/* fill the next segment into the context */
05e08a2a	456	qeth_eddp_create_segment_hdrs(ctx, eddp, data_len);
1da177e4 LT	457	qeth_eddp_create_segment_data_tcp(ctx, eddp, data_len, hcsum);
	458	if (eddp->skb_offset >= eddp->skb->len)
	459	break;
	460	/* prepare headers for next round */
	461	if (eddp->skb->protocol == ETH_P_IP)
	462	eddp->nh.ip4.h.id++;
	463	eddp->th.tcp.h.seq += data_len;
	464	}
	465	}
05e08a2a	466
1da177e4 LT	467	static inline int
	468	qeth_eddp_fill_context_tcp(struct qeth_eddp_context *ctx,
	469	struct sk_buff skb, struct qeth_hdr qhdr)
	470	{
	471	struct qeth_eddp_data *eddp = NULL;
05e08a2a	472
1da177e4 LT	473	QETH_DBF_TEXT(trace, 5, "eddpficx");
	474	/* create our segmentation headers and copy original headers */
	475	if (skb->protocol == ETH_P_IP)
	476	eddp = qeth_eddp_create_eddp_data(qhdr, (u8 *)skb->nh.iph,
	477	skb->nh.iph->ihl*4,
	478	(u8 )skb->h.th, skb->h.th->doff4);
	479	else
	480	eddp = qeth_eddp_create_eddp_data(qhdr, (u8 *)skb->nh.ipv6h,
	481	sizeof(struct ipv6hdr),
	482	(u8 )skb->h.th, skb->h.th->doff4);
	483
	484	if (eddp == NULL) {
	485	QETH_DBF_TEXT(trace, 2, "eddpfcnm");
	486	return -ENOMEM;
	487	}
	488	if (qhdr->hdr.l2.id == QETH_HEADER_TYPE_LAYER2) {
	489	memcpy(&eddp->mac, eth_hdr(skb), ETH_HLEN);
	490	#ifdef CONFIG_QETH_VLAN
	491	if (eddp->mac.h_proto == __constant_htons(ETH_P_8021Q)) {
	492	eddp->vlan[0] = __constant_htons(skb->protocol);
	493	eddp->vlan[1] = htons(vlan_tx_tag_get(skb));
	494	}
	495	#endif /* CONFIG_QETH_VLAN */
	496	}
	497	/* the next flags will only be set on the last segment */
	498	eddp->th.tcp.h.fin = 0;
	499	eddp->th.tcp.h.psh = 0;
	500	eddp->skb = skb;
	501	/* begin segmentation and fill context */
	502	__qeth_eddp_fill_context_tcp(ctx, eddp);
	503	kfree(eddp);
	504	return 0;
	505	}
	506
	507	static inline void
	508	qeth_eddp_calc_num_pages(struct qeth_eddp_context ctx, struct sk_buff skb,
	509	int hdr_len)
	510	{
	511	int skbs_per_page;
05e08a2a	512
1da177e4 LT	513	QETH_DBF_TEXT(trace, 5, "eddpcanp");
	514	/* can we put multiple skbs in one page? */
	515	skbs_per_page = PAGE_SIZE / (skb_shinfo(skb)->tso_size + hdr_len);
	516	if (skbs_per_page > 1){
	517	ctx->num_pages = (skb_shinfo(skb)->tso_segs + 1) /
	518	skbs_per_page + 1;
	519	ctx->elements_per_skb = 1;
	520	} else {
	521	/* no -> how many elements per skb? */
	522	ctx->elements_per_skb = (skb_shinfo(skb)->tso_size + hdr_len +
	523	PAGE_SIZE) >> PAGE_SHIFT;
	524	ctx->num_pages = ctx->elements_per_skb *
	525	(skb_shinfo(skb)->tso_segs + 1);
	526	}
	527	ctx->num_elements = ctx->elements_per_skb *
	528	(skb_shinfo(skb)->tso_segs + 1);
	529	}
	530
	531	static inline struct qeth_eddp_context *
	532	qeth_eddp_create_context_generic(struct qeth_card card, struct sk_buff skb,
	533	int hdr_len)
	534	{
	535	struct qeth_eddp_context *ctx = NULL;
	536	u8 *addr;
	537	int i;
	538
	539	QETH_DBF_TEXT(trace, 5, "creddpcg");
	540	/* create the context and allocate pages */
	541	ctx = kmalloc(sizeof(struct qeth_eddp_context), GFP_ATOMIC);
	542	if (ctx == NULL){
	543	QETH_DBF_TEXT(trace, 2, "ceddpcn1");
	544	return NULL;
	545	}
	546	memset(ctx, 0, sizeof(struct qeth_eddp_context));
	547	ctx->type = QETH_LARGE_SEND_EDDP;
	548	qeth_eddp_calc_num_pages(ctx, skb, hdr_len);
	549	if (ctx->elements_per_skb > QETH_MAX_BUFFER_ELEMENTS(card)){
	550	QETH_DBF_TEXT(trace, 2, "ceddpcis");
	551	kfree(ctx);
	552	return NULL;
	553	}
	554	ctx->pages = kmalloc(ctx->num_pages * sizeof(u8 *), GFP_ATOMIC);
	555	if (ctx->pages == NULL){
	556	QETH_DBF_TEXT(trace, 2, "ceddpcn2");
	557	kfree(ctx);
	558	return NULL;
	559	}
	560	memset(ctx->pages, 0, ctx->num_pages * sizeof(u8 *));
	561	for (i = 0; i < ctx->num_pages; ++i){
	562	addr = (u8 *)__get_free_page(GFP_ATOMIC);
	563	if (addr == NULL){
	564	QETH_DBF_TEXT(trace, 2, "ceddpcn3");
	565	ctx->num_pages = i;
	566	qeth_eddp_free_context(ctx);
	567	return NULL;
	568	}
	569	memset(addr, 0, PAGE_SIZE);
	570	ctx->pages[i] = addr;
	571	}
	572	ctx->elements = kmalloc(ctx->num_elements *
	573	sizeof(struct qeth_eddp_element), GFP_ATOMIC);
	574	if (ctx->elements == NULL){
	575	QETH_DBF_TEXT(trace, 2, "ceddpcn4");
	576	qeth_eddp_free_context(ctx);
577	return NULL;
578	}
579	memset(ctx->elements, 0,
580	ctx->num_elements * sizeof(struct qeth_eddp_element));
581	/* reset num_elements; will be incremented again in fill_buffer to
582	* reflect number of actually used elements */
583	ctx->num_elements = 0;
584	return ctx;
585	}
586
587	static inline struct qeth_eddp_context *
588	qeth_eddp_create_context_tcp(struct qeth_card card, struct sk_buff skb,
589	struct qeth_hdr *qhdr)
590	{
591	struct qeth_eddp_context *ctx = NULL;
05e08a2a	592
1da177e4 LT	593	QETH_DBF_TEXT(trace, 5, "creddpct");
	594	if (skb->protocol == ETH_P_IP)
	595	ctx = qeth_eddp_create_context_generic(card, skb,
	596	sizeof(struct qeth_hdr) + skb->nh.iph->ihl*4 +
	597	skb->h.th->doff*4);
	598	else if (skb->protocol == ETH_P_IPV6)
	599	ctx = qeth_eddp_create_context_generic(card, skb,
	600	sizeof(struct qeth_hdr) + sizeof(struct ipv6hdr) +
	601	skb->h.th->doff*4);
	602	else
	603	QETH_DBF_TEXT(trace, 2, "cetcpinv");
	604
	605	if (ctx == NULL) {
	606	QETH_DBF_TEXT(trace, 2, "creddpnl");
	607	return NULL;
	608	}
	609	if (qeth_eddp_fill_context_tcp(ctx, skb, qhdr)){
	610	QETH_DBF_TEXT(trace, 2, "ceddptfe");
	611	qeth_eddp_free_context(ctx);
	612	return NULL;
	613	}
	614	atomic_set(&ctx->refcnt, 1);
	615	return ctx;
	616	}
	617
	618	struct qeth_eddp_context *
	619	qeth_eddp_create_context(struct qeth_card card, struct sk_buff skb,
	620	struct qeth_hdr *qhdr)
	621	{
	622	QETH_DBF_TEXT(trace, 5, "creddpc");
	623	switch (skb->sk->sk_protocol){
	624	case IPPROTO_TCP:
	625	return qeth_eddp_create_context_tcp(card, skb, qhdr);
	626	default:
	627	QETH_DBF_TEXT(trace, 2, "eddpinvp");
	628	}
	629	return NULL;
	630	}
	631
	632