2 * linux/drivers/s390/net/qeth_eddp.c
4 * Enhanced Device Driver Packing (EDDP) support for the qeth driver.
6 * Copyright 2004 IBM Corporation
8 * Author(s): Thomas Spatzier <tspat@de.ibm.com>
11 #include <linux/errno.h>
13 #include <linux/inetdevice.h>
14 #include <linux/netdevice.h>
15 #include <linux/kernel.h>
16 #include <linux/tcp.h>
18 #include <linux/skbuff.h>
24 #include "qeth_eddp.h"
27 qeth_eddp_check_buffers_for_context(struct qeth_qdio_out_q *queue,
28 struct qeth_eddp_context *ctx)
30 int index = queue->next_buf_to_fill;
31 int elements_needed = ctx->num_elements;
32 int elements_in_buffer;
34 int buffers_needed = 0;
36 QETH_DBF_TEXT(trace, 5, "eddpcbfc");
37 while(elements_needed > 0) {
39 if (atomic_read(&queue->bufs[index].state) !=
43 elements_in_buffer = QETH_MAX_BUFFER_ELEMENTS(queue->card) -
44 queue->bufs[index].next_element_to_fill;
45 skbs_in_buffer = elements_in_buffer / ctx->elements_per_skb;
46 elements_needed -= skbs_in_buffer * ctx->elements_per_skb;
47 index = (index + 1) % QDIO_MAX_BUFFERS_PER_Q;
49 return buffers_needed;
53 qeth_eddp_free_context(struct qeth_eddp_context *ctx)
57 QETH_DBF_TEXT(trace, 5, "eddpfctx");
58 for (i = 0; i < ctx->num_pages; ++i)
59 free_page((unsigned long)ctx->pages[i]);
67 qeth_eddp_get_context(struct qeth_eddp_context *ctx)
69 atomic_inc(&ctx->refcnt);
73 qeth_eddp_put_context(struct qeth_eddp_context *ctx)
75 if (atomic_dec_return(&ctx->refcnt) == 0)
76 qeth_eddp_free_context(ctx);
80 qeth_eddp_buf_release_contexts(struct qeth_qdio_out_buffer *buf)
82 struct qeth_eddp_context_reference *ref;
84 QETH_DBF_TEXT(trace, 6, "eddprctx");
85 while (!list_empty(&buf->ctx_list)){
86 ref = list_entry(buf->ctx_list.next,
87 struct qeth_eddp_context_reference, list);
88 qeth_eddp_put_context(ref->ctx);
95 qeth_eddp_buf_ref_context(struct qeth_qdio_out_buffer *buf,
96 struct qeth_eddp_context *ctx)
98 struct qeth_eddp_context_reference *ref;
100 QETH_DBF_TEXT(trace, 6, "eddprfcx");
101 ref = kmalloc(sizeof(struct qeth_eddp_context_reference), GFP_ATOMIC);
104 qeth_eddp_get_context(ctx);
106 list_add_tail(&ref->list, &buf->ctx_list);
111 qeth_eddp_fill_buffer(struct qeth_qdio_out_q *queue,
112 struct qeth_eddp_context *ctx,
115 struct qeth_qdio_out_buffer *buf = NULL;
116 struct qdio_buffer *buffer;
117 int elements = ctx->num_elements;
123 QETH_DBF_TEXT(trace, 5, "eddpfibu");
124 while (elements > 0) {
125 buf = &queue->bufs[index];
126 if (atomic_read(&buf->state) != QETH_QDIO_BUF_EMPTY){
127 /* normally this should not happen since we checked for
128 * available elements in qeth_check_elements_for_context
133 PRINT_WARN("could only partially fill eddp "
138 /* check if the whole next skb fits into current buffer */
139 if ((QETH_MAX_BUFFER_ELEMENTS(queue->card) -
140 buf->next_element_to_fill)
141 < ctx->elements_per_skb){
142 /* no -> go to next buffer */
143 atomic_set(&buf->state, QETH_QDIO_BUF_PRIMED);
144 index = (index + 1) % QDIO_MAX_BUFFERS_PER_Q;
146 /* new buffer, so we have to add ctx to buffer'ctx_list
147 * and increment ctx's refcnt */
153 if (qeth_eddp_buf_ref_context(buf, ctx)){
154 PRINT_WARN("no memory to create eddp context "
159 buffer = buf->buffer;
160 /* fill one skb into buffer */
161 for (i = 0; i < ctx->elements_per_skb; ++i){
162 buffer->element[buf->next_element_to_fill].addr =
163 ctx->elements[element].addr;
164 buffer->element[buf->next_element_to_fill].length =
165 ctx->elements[element].length;
166 buffer->element[buf->next_element_to_fill].flags =
167 ctx->elements[element].flags;
168 buf->next_element_to_fill++;
174 if (!queue->do_pack) {
175 QETH_DBF_TEXT(trace, 6, "fillbfnp");
176 /* set state to PRIMED -> will be flushed */
177 if (buf->next_element_to_fill > 0){
178 atomic_set(&buf->state, QETH_QDIO_BUF_PRIMED);
182 if (queue->card->options.performance_stats)
183 queue->card->perf_stats.skbs_sent_pack++;
184 QETH_DBF_TEXT(trace, 6, "fillbfpa");
185 if (buf->next_element_to_fill >=
186 QETH_MAX_BUFFER_ELEMENTS(queue->card)) {
188 * packed buffer if full -> set state PRIMED
191 atomic_set(&buf->state, QETH_QDIO_BUF_PRIMED);
200 qeth_eddp_create_segment_hdrs(struct qeth_eddp_context *ctx,
201 struct qeth_eddp_data *eddp, int data_len)
207 struct qeth_eddp_element *element;
209 QETH_DBF_TEXT(trace, 5, "eddpcrsh");
210 page = ctx->pages[ctx->offset >> PAGE_SHIFT];
211 page_offset = ctx->offset % PAGE_SIZE;
212 element = &ctx->elements[ctx->num_elements];
213 pkt_len = eddp->nhl + eddp->thl + data_len;
214 /* FIXME: layer2 and VLAN !!! */
215 if (eddp->qh.hdr.l2.id == QETH_HEADER_TYPE_LAYER2)
217 if (eddp->mac.h_proto == __constant_htons(ETH_P_8021Q))
218 pkt_len += VLAN_HLEN;
219 /* does complete packet fit in current page ? */
220 page_remainder = PAGE_SIZE - page_offset;
221 if (page_remainder < (sizeof(struct qeth_hdr) + pkt_len)){
222 /* no -> go to start of next page */
223 ctx->offset += page_remainder;
224 page = ctx->pages[ctx->offset >> PAGE_SHIFT];
227 memcpy(page + page_offset, &eddp->qh, sizeof(struct qeth_hdr));
228 element->addr = page + page_offset;
229 element->length = sizeof(struct qeth_hdr);
230 ctx->offset += sizeof(struct qeth_hdr);
231 page_offset += sizeof(struct qeth_hdr);
232 /* add mac header (?) */
233 if (eddp->qh.hdr.l2.id == QETH_HEADER_TYPE_LAYER2){
234 memcpy(page + page_offset, &eddp->mac, ETH_HLEN);
235 element->length += ETH_HLEN;
236 ctx->offset += ETH_HLEN;
237 page_offset += ETH_HLEN;
240 if (eddp->mac.h_proto == __constant_htons(ETH_P_8021Q)){
241 memcpy(page + page_offset, &eddp->vlan, VLAN_HLEN);
242 element->length += VLAN_HLEN;
243 ctx->offset += VLAN_HLEN;
244 page_offset += VLAN_HLEN;
246 /* add network header */
247 memcpy(page + page_offset, (u8 *)&eddp->nh, eddp->nhl);
248 element->length += eddp->nhl;
249 eddp->nh_in_ctx = page + page_offset;
250 ctx->offset += eddp->nhl;
251 page_offset += eddp->nhl;
252 /* add transport header */
253 memcpy(page + page_offset, (u8 *)&eddp->th, eddp->thl);
254 element->length += eddp->thl;
255 eddp->th_in_ctx = page + page_offset;
256 ctx->offset += eddp->thl;
260 qeth_eddp_copy_data_tcp(char *dst, struct qeth_eddp_data *eddp, int len,
263 struct skb_frag_struct *frag;
268 QETH_DBF_TEXT(trace, 5, "eddpcdtc");
269 if (skb_shinfo(eddp->skb)->nr_frags == 0) {
270 skb_copy_from_linear_data_offset(eddp->skb, eddp->skb_offset,
272 *hcsum = csum_partial(eddp->skb->data + eddp->skb_offset, len,
274 eddp->skb_offset += len;
277 if (eddp->frag < 0) {
278 /* we're in skb->data */
279 left_in_frag = (eddp->skb->len - eddp->skb->data_len)
281 src = eddp->skb->data + eddp->skb_offset;
283 frag = &skb_shinfo(eddp->skb)->
285 left_in_frag = frag->size - eddp->frag_offset;
287 (page_to_pfn(frag->page) << PAGE_SHIFT)+
288 frag->page_offset + eddp->frag_offset);
290 if (left_in_frag <= 0) {
292 eddp->frag_offset = 0;
295 copy_len = min(left_in_frag, len);
296 memcpy(dst, src, copy_len);
297 *hcsum = csum_partial(src, copy_len, *hcsum);
299 eddp->frag_offset += copy_len;
300 eddp->skb_offset += copy_len;
307 qeth_eddp_create_segment_data_tcp(struct qeth_eddp_context *ctx,
308 struct qeth_eddp_data *eddp, int data_len,
314 struct qeth_eddp_element *element;
317 QETH_DBF_TEXT(trace, 5, "eddpcsdt");
318 page = ctx->pages[ctx->offset >> PAGE_SHIFT];
319 page_offset = ctx->offset % PAGE_SIZE;
320 element = &ctx->elements[ctx->num_elements];
322 page_remainder = PAGE_SIZE - page_offset;
323 if (page_remainder < data_len){
324 qeth_eddp_copy_data_tcp(page + page_offset, eddp,
325 page_remainder, &hcsum);
326 element->length += page_remainder;
328 element->flags = SBAL_FLAGS_FIRST_FRAG;
330 element->flags = SBAL_FLAGS_MIDDLE_FRAG;
333 data_len -= page_remainder;
334 ctx->offset += page_remainder;
335 page = ctx->pages[ctx->offset >> PAGE_SHIFT];
337 element->addr = page + page_offset;
339 qeth_eddp_copy_data_tcp(page + page_offset, eddp,
341 element->length += data_len;
343 element->flags = SBAL_FLAGS_LAST_FRAG;
345 ctx->offset += data_len;
350 ((struct tcphdr *)eddp->th_in_ctx)->check = csum_fold(hcsum);
354 qeth_eddp_check_tcp4_hdr(struct qeth_eddp_data *eddp, int data_len)
356 __wsum phcsum; /* pseudo header checksum */
358 QETH_DBF_TEXT(trace, 5, "eddpckt4");
359 eddp->th.tcp.h.check = 0;
360 /* compute pseudo header checksum */
361 phcsum = csum_tcpudp_nofold(eddp->nh.ip4.h.saddr, eddp->nh.ip4.h.daddr,
362 eddp->thl + data_len, IPPROTO_TCP, 0);
363 /* compute checksum of tcp header */
364 return csum_partial((u8 *)&eddp->th, eddp->thl, phcsum);
368 qeth_eddp_check_tcp6_hdr(struct qeth_eddp_data *eddp, int data_len)
371 __wsum phcsum; /* pseudo header checksum */
373 QETH_DBF_TEXT(trace, 5, "eddpckt6");
374 eddp->th.tcp.h.check = 0;
375 /* compute pseudo header checksum */
376 phcsum = csum_partial((u8 *)&eddp->nh.ip6.h.saddr,
377 sizeof(struct in6_addr), 0);
378 phcsum = csum_partial((u8 *)&eddp->nh.ip6.h.daddr,
379 sizeof(struct in6_addr), phcsum);
380 proto = htonl(IPPROTO_TCP);
381 phcsum = csum_partial((u8 *)&proto, sizeof(u32), phcsum);
385 static struct qeth_eddp_data *
386 qeth_eddp_create_eddp_data(struct qeth_hdr *qh, u8 *nh, u8 nhl, u8 *th, u8 thl)
388 struct qeth_eddp_data *eddp;
390 QETH_DBF_TEXT(trace, 5, "eddpcrda");
391 eddp = kzalloc(sizeof(struct qeth_eddp_data), GFP_ATOMIC);
395 memcpy(&eddp->qh, qh, sizeof(struct qeth_hdr));
396 memcpy(&eddp->nh, nh, nhl);
397 memcpy(&eddp->th, th, thl);
398 eddp->frag = -1; /* initially we're in skb->data */
404 __qeth_eddp_fill_context_tcp(struct qeth_eddp_context *ctx,
405 struct qeth_eddp_data *eddp)
411 QETH_DBF_TEXT(trace, 5, "eddpftcp");
412 eddp->skb_offset = sizeof(struct qeth_hdr) + eddp->nhl + eddp->thl;
413 if (eddp->qh.hdr.l2.id == QETH_HEADER_TYPE_LAYER2) {
414 eddp->skb_offset += sizeof(struct ethhdr);
415 #ifdef CONFIG_QETH_VLAN
416 if (eddp->mac.h_proto == __constant_htons(ETH_P_8021Q))
417 eddp->skb_offset += VLAN_HLEN;
418 #endif /* CONFIG_QETH_VLAN */
420 tcph = tcp_hdr(eddp->skb);
421 while (eddp->skb_offset < eddp->skb->len) {
422 data_len = min((int)skb_shinfo(eddp->skb)->gso_size,
423 (int)(eddp->skb->len - eddp->skb_offset));
424 /* prepare qdio hdr */
425 if (eddp->qh.hdr.l2.id == QETH_HEADER_TYPE_LAYER2){
426 eddp->qh.hdr.l2.pkt_length = data_len + ETH_HLEN +
427 eddp->nhl + eddp->thl -
428 sizeof(struct qeth_hdr);
429 #ifdef CONFIG_QETH_VLAN
430 if (eddp->mac.h_proto == __constant_htons(ETH_P_8021Q))
431 eddp->qh.hdr.l2.pkt_length += VLAN_HLEN;
432 #endif /* CONFIG_QETH_VLAN */
434 eddp->qh.hdr.l3.length = data_len + eddp->nhl +
437 if (eddp->skb->protocol == htons(ETH_P_IP)){
438 eddp->nh.ip4.h.tot_len = htons(data_len + eddp->nhl +
440 eddp->nh.ip4.h.check = 0;
441 eddp->nh.ip4.h.check =
442 ip_fast_csum((u8 *)&eddp->nh.ip4.h,
445 eddp->nh.ip6.h.payload_len = htons(data_len + eddp->thl);
446 /* prepare tcp hdr */
447 if (data_len == (eddp->skb->len - eddp->skb_offset)){
448 /* last segment -> set FIN and PSH flags */
449 eddp->th.tcp.h.fin = tcph->fin;
450 eddp->th.tcp.h.psh = tcph->psh;
452 if (eddp->skb->protocol == htons(ETH_P_IP))
453 hcsum = qeth_eddp_check_tcp4_hdr(eddp, data_len);
455 hcsum = qeth_eddp_check_tcp6_hdr(eddp, data_len);
456 /* fill the next segment into the context */
457 qeth_eddp_create_segment_hdrs(ctx, eddp, data_len);
458 qeth_eddp_create_segment_data_tcp(ctx, eddp, data_len, hcsum);
459 if (eddp->skb_offset >= eddp->skb->len)
461 /* prepare headers for next round */
462 if (eddp->skb->protocol == htons(ETH_P_IP))
463 eddp->nh.ip4.h.id = htons(ntohs(eddp->nh.ip4.h.id) + 1);
464 eddp->th.tcp.h.seq = htonl(ntohl(eddp->th.tcp.h.seq) + data_len);
469 qeth_eddp_fill_context_tcp(struct qeth_eddp_context *ctx,
470 struct sk_buff *skb, struct qeth_hdr *qhdr)
472 struct qeth_eddp_data *eddp = NULL;
474 QETH_DBF_TEXT(trace, 5, "eddpficx");
475 /* create our segmentation headers and copy original headers */
476 if (skb->protocol == htons(ETH_P_IP))
477 eddp = qeth_eddp_create_eddp_data(qhdr,
478 skb_network_header(skb),
480 skb_transport_header(skb),
483 eddp = qeth_eddp_create_eddp_data(qhdr,
484 skb_network_header(skb),
485 sizeof(struct ipv6hdr),
486 skb_transport_header(skb),
490 QETH_DBF_TEXT(trace, 2, "eddpfcnm");
493 if (qhdr->hdr.l2.id == QETH_HEADER_TYPE_LAYER2) {
494 skb_set_mac_header(skb, sizeof(struct qeth_hdr));
495 memcpy(&eddp->mac, eth_hdr(skb), ETH_HLEN);
496 #ifdef CONFIG_QETH_VLAN
497 if (eddp->mac.h_proto == __constant_htons(ETH_P_8021Q)) {
498 eddp->vlan[0] = skb->protocol;
499 eddp->vlan[1] = htons(vlan_tx_tag_get(skb));
501 #endif /* CONFIG_QETH_VLAN */
503 /* the next flags will only be set on the last segment */
504 eddp->th.tcp.h.fin = 0;
505 eddp->th.tcp.h.psh = 0;
507 /* begin segmentation and fill context */
508 __qeth_eddp_fill_context_tcp(ctx, eddp);
514 qeth_eddp_calc_num_pages(struct qeth_eddp_context *ctx, struct sk_buff *skb,
519 QETH_DBF_TEXT(trace, 5, "eddpcanp");
520 /* can we put multiple skbs in one page? */
521 skbs_per_page = PAGE_SIZE / (skb_shinfo(skb)->gso_size + hdr_len);
522 if (skbs_per_page > 1){
523 ctx->num_pages = (skb_shinfo(skb)->gso_segs + 1) /
525 ctx->elements_per_skb = 1;
527 /* no -> how many elements per skb? */
528 ctx->elements_per_skb = (skb_shinfo(skb)->gso_size + hdr_len +
529 PAGE_SIZE) >> PAGE_SHIFT;
530 ctx->num_pages = ctx->elements_per_skb *
531 (skb_shinfo(skb)->gso_segs + 1);
533 ctx->num_elements = ctx->elements_per_skb *
534 (skb_shinfo(skb)->gso_segs + 1);
537 static struct qeth_eddp_context *
538 qeth_eddp_create_context_generic(struct qeth_card *card, struct sk_buff *skb,
541 struct qeth_eddp_context *ctx = NULL;
545 QETH_DBF_TEXT(trace, 5, "creddpcg");
546 /* create the context and allocate pages */
547 ctx = kzalloc(sizeof(struct qeth_eddp_context), GFP_ATOMIC);
549 QETH_DBF_TEXT(trace, 2, "ceddpcn1");
552 ctx->type = QETH_LARGE_SEND_EDDP;
553 qeth_eddp_calc_num_pages(ctx, skb, hdr_len);
554 if (ctx->elements_per_skb > QETH_MAX_BUFFER_ELEMENTS(card)){
555 QETH_DBF_TEXT(trace, 2, "ceddpcis");
559 ctx->pages = kcalloc(ctx->num_pages, sizeof(u8 *), GFP_ATOMIC);
560 if (ctx->pages == NULL){
561 QETH_DBF_TEXT(trace, 2, "ceddpcn2");
565 for (i = 0; i < ctx->num_pages; ++i){
566 addr = (u8 *)__get_free_page(GFP_ATOMIC);
568 QETH_DBF_TEXT(trace, 2, "ceddpcn3");
570 qeth_eddp_free_context(ctx);
573 memset(addr, 0, PAGE_SIZE);
574 ctx->pages[i] = addr;
576 ctx->elements = kcalloc(ctx->num_elements,
577 sizeof(struct qeth_eddp_element), GFP_ATOMIC);
578 if (ctx->elements == NULL){
579 QETH_DBF_TEXT(trace, 2, "ceddpcn4");
580 qeth_eddp_free_context(ctx);
583 /* reset num_elements; will be incremented again in fill_buffer to
584 * reflect number of actually used elements */
585 ctx->num_elements = 0;
589 static struct qeth_eddp_context *
590 qeth_eddp_create_context_tcp(struct qeth_card *card, struct sk_buff *skb,
591 struct qeth_hdr *qhdr)
593 struct qeth_eddp_context *ctx = NULL;
595 QETH_DBF_TEXT(trace, 5, "creddpct");
596 if (skb->protocol == htons(ETH_P_IP))
597 ctx = qeth_eddp_create_context_generic(card, skb,
598 (sizeof(struct qeth_hdr) +
601 else if (skb->protocol == htons(ETH_P_IPV6))
602 ctx = qeth_eddp_create_context_generic(card, skb,
603 sizeof(struct qeth_hdr) + sizeof(struct ipv6hdr) +
606 QETH_DBF_TEXT(trace, 2, "cetcpinv");
609 QETH_DBF_TEXT(trace, 2, "creddpnl");
612 if (qeth_eddp_fill_context_tcp(ctx, skb, qhdr)){
613 QETH_DBF_TEXT(trace, 2, "ceddptfe");
614 qeth_eddp_free_context(ctx);
617 atomic_set(&ctx->refcnt, 1);
621 struct qeth_eddp_context *
622 qeth_eddp_create_context(struct qeth_card *card, struct sk_buff *skb,
623 struct qeth_hdr *qhdr, unsigned char sk_protocol)
625 QETH_DBF_TEXT(trace, 5, "creddpc");
626 switch (sk_protocol) {
628 return qeth_eddp_create_context_tcp(card, skb, qhdr);
630 QETH_DBF_TEXT(trace, 2, "eddpinvp");