drivers/s390/net/qeth_eddp.c

   1 /*
   2  * linux/drivers/s390/net/qeth_eddp.c
   3  *
   4  * Enhanced Device Driver Packing (EDDP) support for the qeth driver.
   5  *
   6  * Copyright 2004 IBM Corporation
   7  *
   8  *    Author(s): Thomas Spatzier <tspat@de.ibm.com>
   9  *
  10  */
  11 #include <linux/errno.h>
  12 #include <linux/ip.h>
  13 #include <linux/inetdevice.h>
  14 #include <linux/netdevice.h>
  15 #include <linux/kernel.h>
  16 #include <linux/tcp.h>
  17 #include <net/tcp.h>
  18 #include <linux/skbuff.h>
  19
  20 #include <net/ip.h>
  21
  22 #include "qeth.h"
  23 #include "qeth_mpc.h"
  24 #include "qeth_eddp.h"
  25
  26 int
  27 qeth_eddp_check_buffers_for_context(struct qeth_qdio_out_q *queue,
  28                                     struct qeth_eddp_context *ctx)
  29 {
  30         int index = queue->next_buf_to_fill;
  31         int elements_needed = ctx->num_elements;
  32         int elements_in_buffer;
  33         int skbs_in_buffer;
  34         int buffers_needed = 0;
  35
  36         QETH_DBF_TEXT(trace, 5, "eddpcbfc");
  37         while(elements_needed > 0) {
  38                 buffers_needed++;
  39                 if (atomic_read(&queue->bufs[index].state) !=
  40                                 QETH_QDIO_BUF_EMPTY)
  41                         return -EBUSY;
  42
  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;
  48         }
  49         return buffers_needed;
  50 }
  51
  52 static void
  53 qeth_eddp_free_context(struct qeth_eddp_context *ctx)
  54 {
  55         int i;
  56
  57         QETH_DBF_TEXT(trace, 5, "eddpfctx");
  58         for (i = 0; i < ctx->num_pages; ++i)
  59                 free_page((unsigned long)ctx->pages[i]);
  60         kfree(ctx->pages);
  61         kfree(ctx->elements);
  62         kfree(ctx);
  63 }
  64
  65
  66 static inline void
  67 qeth_eddp_get_context(struct qeth_eddp_context *ctx)
  68 {
  69         atomic_inc(&ctx->refcnt);
  70 }
  71
  72 void
  73 qeth_eddp_put_context(struct qeth_eddp_context *ctx)
  74 {
  75         if (atomic_dec_return(&ctx->refcnt) == 0)
  76                 qeth_eddp_free_context(ctx);
  77 }
  78
  79 void
  80 qeth_eddp_buf_release_contexts(struct qeth_qdio_out_buffer *buf)
  81 {
  82         struct qeth_eddp_context_reference *ref;
  83
  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);
  89                 list_del(&ref->list);
  90                 kfree(ref);
  91         }
  92 }
  93
  94 static int
  95 qeth_eddp_buf_ref_context(struct qeth_qdio_out_buffer *buf,
  96                           struct qeth_eddp_context *ctx)
  97 {
  98         struct qeth_eddp_context_reference *ref;
  99
 100         QETH_DBF_TEXT(trace, 6, "eddprfcx");
 101         ref = kmalloc(sizeof(struct qeth_eddp_context_reference), GFP_ATOMIC);
 102         if (ref == NULL)
 103                 return -ENOMEM;
 104         qeth_eddp_get_context(ctx);
 105         ref->ctx = ctx;
 106         list_add_tail(&ref->list, &buf->ctx_list);
 107         return 0;
 108 }
 109
 110 int
 111 qeth_eddp_fill_buffer(struct qeth_qdio_out_q *queue,
 112                       struct qeth_eddp_context *ctx,
 113                       int index)
 114 {
 115         struct qeth_qdio_out_buffer *buf = NULL;
 116         struct qdio_buffer *buffer;
 117         int elements = ctx->num_elements;
 118         int element = 0;
 119         int flush_cnt = 0;
 120         int must_refcnt = 1;
 121         int i;
 122
 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
 129                          */
 130                         if (element == 0)
 131                                 return -EBUSY;
 132                         else {
 133                                 PRINT_WARN("could only partially fill eddp "
 134                                            "buffer!\n");
 135                                 goto out;
 136                         }
 137                 }
 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;
 145                         flush_cnt++;
 146                         /* new buffer, so we have to add ctx to buffer'ctx_list
 147                          * and increment ctx's refcnt */
 148                         must_refcnt = 1;
 149                         continue;
 150                 }
 151                 if (must_refcnt){
 152                         must_refcnt = 0;
 153                         if (qeth_eddp_buf_ref_context(buf, ctx)){
 154                                 PRINT_WARN("no memory to create eddp context "
 155                                            "reference\n");
 156                                 goto out_check;
 157                         }
 158                 }
 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++;
 169                         element++;
 170                         elements--;
 171                 }
 172         }
 173 out_check:
 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);
 179                         flush_cnt++;
 180                 }
 181         } else {
 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)) {
 187                         /*
 188                          * packed buffer if full -> set state PRIMED
 189                          * -> will be flushed
 190                          */
 191                         atomic_set(&buf->state, QETH_QDIO_BUF_PRIMED);
 192                         flush_cnt++;
 193                 }
 194         }
 195 out:
 196         return flush_cnt;
 197 }
 198
 199 static void
 200 qeth_eddp_create_segment_hdrs(struct qeth_eddp_context *ctx,
 201                               struct qeth_eddp_data *eddp, int data_len)
 202 {
 203         u8 *page;
 204         int page_remainder;
 205         int page_offset;
 206         int pkt_len;
 207         struct qeth_eddp_element *element;
 208
 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)
 216                 pkt_len += ETH_HLEN;
 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];
 225                 page_offset = 0;
 226         }
 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;
 238         }
 239         /* add VLAN tag */
 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;
 245         }
 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;
 257 }
 258
 259 static void
 260 qeth_eddp_copy_data_tcp(char *dst, struct qeth_eddp_data *eddp, int len,
 261                         __wsum *hcsum)
 262 {
 263         struct skb_frag_struct *frag;
 264         int left_in_frag;
 265         int copy_len;
 266         u8 *src;
 267
 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,
 271                                                  dst, len);
 272                 *hcsum = csum_partial(eddp->skb->data + eddp->skb_offset, len,
 273                                       *hcsum);
 274                 eddp->skb_offset += len;
 275         } else {
 276                 while (len > 0) {
 277                         if (eddp->frag < 0) {
 278                                 /* we're in skb->data */
 279                                 left_in_frag = (eddp->skb->len - eddp->skb->data_len)
 280                                                 - eddp->skb_offset;
 281                                 src = eddp->skb->data + eddp->skb_offset;
 282                         } else {
 283                                 frag = &skb_shinfo(eddp->skb)->
 284                                         frags[eddp->frag];
 285                                 left_in_frag = frag->size - eddp->frag_offset;
 286                                 src = (u8 *)(
 287                                         (page_to_pfn(frag->page) << PAGE_SHIFT)+
 288                                         frag->page_offset + eddp->frag_offset);
 289                         }
 290                         if (left_in_frag <= 0) {
 291                                 eddp->frag++;
 292                                 eddp->frag_offset = 0;
 293                                 continue;
 294                         }
 295                         copy_len = min(left_in_frag, len);
 296                         memcpy(dst, src, copy_len);
 297                         *hcsum = csum_partial(src, copy_len, *hcsum);
 298                         dst += copy_len;
 299                         eddp->frag_offset += copy_len;
 300                         eddp->skb_offset += copy_len;
 301                         len -= copy_len;
 302                 }
 303         }
 304 }
 305
 306 static void
 307 qeth_eddp_create_segment_data_tcp(struct qeth_eddp_context *ctx,
 308                                   struct qeth_eddp_data *eddp, int data_len,
 309                                   __wsum hcsum)
 310 {
 311         u8 *page;
 312         int page_remainder;
 313         int page_offset;
 314         struct qeth_eddp_element *element;
 315         int first_lap = 1;
 316
 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];
 321         while (data_len){
 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;
 327                         if (first_lap)
 328                                 element->flags = SBAL_FLAGS_FIRST_FRAG;
 329                         else
 330                                 element->flags = SBAL_FLAGS_MIDDLE_FRAG;
 331                         ctx->num_elements++;
 332                         element++;
 333                         data_len -= page_remainder;
 334                         ctx->offset += page_remainder;
 335                         page = ctx->pages[ctx->offset >> PAGE_SHIFT];
 336                         page_offset = 0;
 337                         element->addr = page + page_offset;
 338                 } else {
 339                         qeth_eddp_copy_data_tcp(page + page_offset, eddp,
 340                                                 data_len, &hcsum);
 341                         element->length += data_len;
 342                         if (!first_lap)
 343                                 element->flags = SBAL_FLAGS_LAST_FRAG;
 344                         ctx->num_elements++;
 345                         ctx->offset += data_len;
 346                         data_len = 0;
 347                 }
 348                 first_lap = 0;
 349         }
 350         ((struct tcphdr *)eddp->th_in_ctx)->check = csum_fold(hcsum);
 351 }
 352
 353 static __wsum
 354 qeth_eddp_check_tcp4_hdr(struct qeth_eddp_data *eddp, int data_len)
 355 {
 356         __wsum phcsum; /* pseudo header checksum */
 357
 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);
 365 }
 366
 367 static __wsum
 368 qeth_eddp_check_tcp6_hdr(struct qeth_eddp_data *eddp, int data_len)
 369 {
 370         __be32 proto;
 371         __wsum phcsum; /* pseudo header checksum */
 372
 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);
 382         return phcsum;
 383 }
 384
 385 static struct qeth_eddp_data *
 386 qeth_eddp_create_eddp_data(struct qeth_hdr *qh, u8 *nh, u8 nhl, u8 *th, u8 thl)
 387 {
 388         struct qeth_eddp_data *eddp;
 389
 390         QETH_DBF_TEXT(trace, 5, "eddpcrda");
 391         eddp = kzalloc(sizeof(struct qeth_eddp_data), GFP_ATOMIC);
 392         if (eddp){
 393                 eddp->nhl = nhl;
 394                 eddp->thl = thl;
 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 */
 399         }
 400         return eddp;
 401 }
 402
 403 static void
 404 __qeth_eddp_fill_context_tcp(struct qeth_eddp_context *ctx,
 405                              struct qeth_eddp_data *eddp)
 406 {
 407         struct tcphdr *tcph;
 408         int data_len;
 409         __wsum hcsum;
 410
 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 */
 419        }
 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 */
 433                 } else
 434                         eddp->qh.hdr.l3.length = data_len + eddp->nhl +
 435                                                  eddp->thl;
 436                 /* prepare ip hdr */
 437                 if (eddp->skb->protocol == htons(ETH_P_IP)){
 438                         eddp->nh.ip4.h.tot_len = htons(data_len + eddp->nhl +
 439                                                  eddp->thl);
 440                         eddp->nh.ip4.h.check = 0;
 441                         eddp->nh.ip4.h.check =
 442                                 ip_fast_csum((u8 *)&eddp->nh.ip4.h,
 443                                                 eddp->nh.ip4.h.ihl);
 444                 } else
 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;
 451                 }
 452                 if (eddp->skb->protocol == htons(ETH_P_IP))
 453                         hcsum = qeth_eddp_check_tcp4_hdr(eddp, data_len);
 454                 else
 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)
 460                         break;
 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);
 465         }
 466 }
 467
 468 static int
 469 qeth_eddp_fill_context_tcp(struct qeth_eddp_context *ctx,
 470                            struct sk_buff *skb, struct qeth_hdr *qhdr)
 471 {
 472         struct qeth_eddp_data *eddp = NULL;
 473
 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),
 479                                                   ip_hdrlen(skb),
 480                                                   skb_transport_header(skb),
 481                                                   tcp_hdrlen(skb));
 482         else
 483                 eddp = qeth_eddp_create_eddp_data(qhdr,
 484                                                   skb_network_header(skb),
 485                                                   sizeof(struct ipv6hdr),
 486                                                   skb_transport_header(skb),
 487                                                   tcp_hdrlen(skb));
 488
 489         if (eddp == NULL) {
 490                 QETH_DBF_TEXT(trace, 2, "eddpfcnm");
 491                 return -ENOMEM;
 492         }
 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));
 500                 }
 501 #endif /* CONFIG_QETH_VLAN */
 502         }
 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;
 506         eddp->skb = skb;
 507         /* begin segmentation and fill context */
 508         __qeth_eddp_fill_context_tcp(ctx, eddp);
 509         kfree(eddp);
 510         return 0;
 511 }
 512
 513 static void
 514 qeth_eddp_calc_num_pages(struct qeth_eddp_context *ctx, struct sk_buff *skb,
 515                          int hdr_len)
 516 {
 517         int skbs_per_page;
 518
 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) /
 524                                  skbs_per_page + 1;
 525                 ctx->elements_per_skb = 1;
 526         } else {
 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);
 532         }
 533         ctx->num_elements = ctx->elements_per_skb *
 534                             (skb_shinfo(skb)->gso_segs + 1);
 535 }
 536
 537 static struct qeth_eddp_context *
 538 qeth_eddp_create_context_generic(struct qeth_card *card, struct sk_buff *skb,
 539                                  int hdr_len)
 540 {
 541         struct qeth_eddp_context *ctx = NULL;
 542         u8 *addr;
 543         int i;
 544
 545         QETH_DBF_TEXT(trace, 5, "creddpcg");
 546         /* create the context and allocate pages */
 547         ctx = kzalloc(sizeof(struct qeth_eddp_context), GFP_ATOMIC);
 548         if (ctx == NULL){
 549                 QETH_DBF_TEXT(trace, 2, "ceddpcn1");
 550                 return NULL;
 551         }
 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");
 556                 kfree(ctx);
 557                 return NULL;
 558         }
 559         ctx->pages = kcalloc(ctx->num_pages, sizeof(u8 *), GFP_ATOMIC);
 560         if (ctx->pages == NULL){
 561                 QETH_DBF_TEXT(trace, 2, "ceddpcn2");
 562                 kfree(ctx);
 563                 return NULL;
 564         }
 565         for (i = 0; i < ctx->num_pages; ++i){
 566                 addr = (u8 *)__get_free_page(GFP_ATOMIC);
 567                 if (addr == NULL){
 568                         QETH_DBF_TEXT(trace, 2, "ceddpcn3");
 569                         ctx->num_pages = i;
 570                         qeth_eddp_free_context(ctx);
 571                         return NULL;
 572                 }
 573                 memset(addr, 0, PAGE_SIZE);
 574                 ctx->pages[i] = addr;
 575         }
 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);
 581                 return NULL;
 582         }
 583         /* reset num_elements; will be incremented again in fill_buffer to
 584          * reflect number of actually used elements */
 585         ctx->num_elements = 0;
 586         return ctx;
 587 }
 588
 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)
 592 {
 593         struct qeth_eddp_context *ctx = NULL;
 594
 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) +
 599                                                         ip_hdrlen(skb) +
 600                                                         tcp_hdrlen(skb)));
 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) +
 604                         tcp_hdrlen(skb));
 605         else
 606                 QETH_DBF_TEXT(trace, 2, "cetcpinv");
 607
 608         if (ctx == NULL) {
 609                 QETH_DBF_TEXT(trace, 2, "creddpnl");
 610                 return NULL;
 611         }
 612         if (qeth_eddp_fill_context_tcp(ctx, skb, qhdr)){
 613                 QETH_DBF_TEXT(trace, 2, "ceddptfe");
 614                 qeth_eddp_free_context(ctx);
 615                 return NULL;
 616         }
 617         atomic_set(&ctx->refcnt, 1);
 618         return ctx;
 619 }
 620
 621 struct qeth_eddp_context *
 622 qeth_eddp_create_context(struct qeth_card *card, struct sk_buff *skb,
 623                          struct qeth_hdr *qhdr)
 624 {
 625         QETH_DBF_TEXT(trace, 5, "creddpc");
 626         switch (skb->sk->sk_protocol){
 627         case IPPROTO_TCP:
 628                 return qeth_eddp_create_context_tcp(card, skb, qhdr);
 629         default:
 630                 QETH_DBF_TEXT(trace, 2, "eddpinvp");
 631         }
 632         return NULL;
 633 }