drivers/s390/net/qeth_eddp.c

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