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                 memcpy(dst, eddp->skb->data + eddp->skb_offset, len);
 271                 *hcsum = csum_partial(eddp->skb->data + eddp->skb_offset, len,
 272                                       *hcsum);
 273                 eddp->skb_offset += len;
 274         } else {
 275                 while (len > 0) {
 276                         if (eddp->frag < 0) {
 277                                 /* we're in skb->data */
 278                                 left_in_frag = (eddp->skb->len - eddp->skb->data_len)
 279                                                 - eddp->skb_offset;
 280                                 src = eddp->skb->data + eddp->skb_offset;
 281                         } else {
 282                                 frag = &skb_shinfo(eddp->skb)->
 283                                         frags[eddp->frag];
 284                                 left_in_frag = frag->size - eddp->frag_offset;
 285                                 src = (u8 *)(
 286                                         (page_to_pfn(frag->page) << PAGE_SHIFT)+
 287                                         frag->page_offset + eddp->frag_offset);
 288                         }
 289                         if (left_in_frag <= 0) {
 290                                 eddp->frag++;
 291                                 eddp->frag_offset = 0;
 292                                 continue;
 293                         }
 294                         copy_len = min(left_in_frag, len);
 295                         memcpy(dst, src, copy_len);
 296                         *hcsum = csum_partial(src, copy_len, *hcsum);
 297                         dst += copy_len;
 298                         eddp->frag_offset += copy_len;
 299                         eddp->skb_offset += copy_len;
 300                         len -= copy_len;
 301                 }
 302         }
 303 }
 304
 305 static void
 306 qeth_eddp_create_segment_data_tcp(struct qeth_eddp_context *ctx,
 307                                   struct qeth_eddp_data *eddp, int data_len,
 308                                   __wsum hcsum)
 309 {
 310         u8 *page;
 311         int page_remainder;
 312         int page_offset;
 313         struct qeth_eddp_element *element;
 314         int first_lap = 1;
 315
 316         QETH_DBF_TEXT(trace, 5, "eddpcsdt");
 317         page = ctx->pages[ctx->offset >> PAGE_SHIFT];
 318         page_offset = ctx->offset % PAGE_SIZE;
 319         element = &ctx->elements[ctx->num_elements];
 320         while (data_len){
 321                 page_remainder = PAGE_SIZE - page_offset;
 322                 if (page_remainder < data_len){
 323                         qeth_eddp_copy_data_tcp(page + page_offset, eddp,
 324                                                 page_remainder, &hcsum);
 325                         element->length += page_remainder;
 326                         if (first_lap)
 327                                 element->flags = SBAL_FLAGS_FIRST_FRAG;
 328                         else
 329                                 element->flags = SBAL_FLAGS_MIDDLE_FRAG;
 330                         ctx->num_elements++;
 331                         element++;
 332                         data_len -= page_remainder;
 333                         ctx->offset += page_remainder;
 334                         page = ctx->pages[ctx->offset >> PAGE_SHIFT];
 335                         page_offset = 0;
 336                         element->addr = page + page_offset;
 337                 } else {
 338                         qeth_eddp_copy_data_tcp(page + page_offset, eddp,
 339                                                 data_len, &hcsum);
 340                         element->length += data_len;
 341                         if (!first_lap)
 342                                 element->flags = SBAL_FLAGS_LAST_FRAG;
 343                         ctx->num_elements++;
 344                         ctx->offset += data_len;
 345                         data_len = 0;
 346                 }
 347                 first_lap = 0;
 348         }
 349         ((struct tcphdr *)eddp->th_in_ctx)->check = csum_fold(hcsum);
 350 }
 351
 352 static __wsum
 353 qeth_eddp_check_tcp4_hdr(struct qeth_eddp_data *eddp, int data_len)
 354 {
 355         __wsum phcsum; /* pseudo header checksum */
 356
 357         QETH_DBF_TEXT(trace, 5, "eddpckt4");
 358         eddp->th.tcp.h.check = 0;
 359         /* compute pseudo header checksum */
 360         phcsum = csum_tcpudp_nofold(eddp->nh.ip4.h.saddr, eddp->nh.ip4.h.daddr,
 361                                     eddp->thl + data_len, IPPROTO_TCP, 0);
 362         /* compute checksum of tcp header */
 363         return csum_partial((u8 *)&eddp->th, eddp->thl, phcsum);
 364 }
 365
 366 static __wsum
 367 qeth_eddp_check_tcp6_hdr(struct qeth_eddp_data *eddp, int data_len)
 368 {
 369         __be32 proto;
 370         __wsum phcsum; /* pseudo header checksum */
 371
 372         QETH_DBF_TEXT(trace, 5, "eddpckt6");
 373         eddp->th.tcp.h.check = 0;
 374         /* compute pseudo header checksum */
 375         phcsum = csum_partial((u8 *)&eddp->nh.ip6.h.saddr,
 376                               sizeof(struct in6_addr), 0);
 377         phcsum = csum_partial((u8 *)&eddp->nh.ip6.h.daddr,
 378                               sizeof(struct in6_addr), phcsum);
 379         proto = htonl(IPPROTO_TCP);
 380         phcsum = csum_partial((u8 *)&proto, sizeof(u32), phcsum);
 381         return phcsum;
 382 }
 383
 384 static struct qeth_eddp_data *
 385 qeth_eddp_create_eddp_data(struct qeth_hdr *qh, u8 *nh, u8 nhl, u8 *th, u8 thl)
 386 {
 387         struct qeth_eddp_data *eddp;
 388
 389         QETH_DBF_TEXT(trace, 5, "eddpcrda");
 390         eddp = kzalloc(sizeof(struct qeth_eddp_data), GFP_ATOMIC);
 391         if (eddp){
 392                 eddp->nhl = nhl;
 393                 eddp->thl = thl;
 394                 memcpy(&eddp->qh, qh, sizeof(struct qeth_hdr));
 395                 memcpy(&eddp->nh, nh, nhl);
 396                 memcpy(&eddp->th, th, thl);
 397                 eddp->frag = -1; /* initially we're in skb->data */
 398         }
 399         return eddp;
 400 }
 401
 402 static void
 403 __qeth_eddp_fill_context_tcp(struct qeth_eddp_context *ctx,
 404                              struct qeth_eddp_data *eddp)
 405 {
 406         struct tcphdr *tcph;
 407         int data_len;
 408         __wsum hcsum;
 409
 410         QETH_DBF_TEXT(trace, 5, "eddpftcp");
 411         eddp->skb_offset = sizeof(struct qeth_hdr) + eddp->nhl + eddp->thl;
 412        if (eddp->qh.hdr.l2.id == QETH_HEADER_TYPE_LAYER2) {
 413                eddp->skb_offset += sizeof(struct ethhdr);
 414 #ifdef CONFIG_QETH_VLAN
 415                if (eddp->mac.h_proto == __constant_htons(ETH_P_8021Q))
 416                        eddp->skb_offset += VLAN_HLEN;
 417 #endif /* CONFIG_QETH_VLAN */
 418        }
 419         tcph = eddp->skb->h.th;
 420         while (eddp->skb_offset < eddp->skb->len) {
 421                 data_len = min((int)skb_shinfo(eddp->skb)->gso_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 == htons(ETH_P_IP)){
 437                         eddp->nh.ip4.h.tot_len = htons(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 = htons(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 == htons(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 */
 456                 qeth_eddp_create_segment_hdrs(ctx, eddp, data_len);
 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 == htons(ETH_P_IP))
 462                         eddp->nh.ip4.h.id = htons(ntohs(eddp->nh.ip4.h.id) + 1);
 463                 eddp->th.tcp.h.seq = htonl(ntohl(eddp->th.tcp.h.seq) + data_len);
 464         }
 465 }
 466
 467 static 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;
 472
 473         QETH_DBF_TEXT(trace, 5, "eddpficx");
 474         /* create our segmentation headers and copy original headers */
 475         if (skb->protocol == htons(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->doff*4);
 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->doff*4);
 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                 skb->mac.raw = (skb->data) + sizeof(struct qeth_hdr);
 490                 memcpy(&eddp->mac, eth_hdr(skb), ETH_HLEN);
 491 #ifdef CONFIG_QETH_VLAN
 492                 if (eddp->mac.h_proto == __constant_htons(ETH_P_8021Q)) {
 493                         eddp->vlan[0] = skb->protocol;
 494                         eddp->vlan[1] = htons(vlan_tx_tag_get(skb));
 495                 }
 496 #endif /* CONFIG_QETH_VLAN */
 497         }
 498         /* the next flags will only be set on the last segment */
 499         eddp->th.tcp.h.fin = 0;
 500         eddp->th.tcp.h.psh = 0;
 501         eddp->skb = skb;
 502         /* begin segmentation and fill context */
 503         __qeth_eddp_fill_context_tcp(ctx, eddp);
 504         kfree(eddp);
 505         return 0;
 506 }
 507
 508 static void
 509 qeth_eddp_calc_num_pages(struct qeth_eddp_context *ctx, struct sk_buff *skb,
 510                          int hdr_len)
 511 {
 512         int skbs_per_page;
 513
 514         QETH_DBF_TEXT(trace, 5, "eddpcanp");
 515         /* can we put multiple skbs in one page? */
 516         skbs_per_page = PAGE_SIZE / (skb_shinfo(skb)->gso_size + hdr_len);
 517         if (skbs_per_page > 1){
 518                 ctx->num_pages = (skb_shinfo(skb)->gso_segs + 1) /
 519                                  skbs_per_page + 1;
 520                 ctx->elements_per_skb = 1;
 521         } else {
 522                 /* no -> how many elements per skb? */
 523                 ctx->elements_per_skb = (skb_shinfo(skb)->gso_size + hdr_len +
 524                                      PAGE_SIZE) >> PAGE_SHIFT;
 525                 ctx->num_pages = ctx->elements_per_skb *
 526                                  (skb_shinfo(skb)->gso_segs + 1);
 527         }
 528         ctx->num_elements = ctx->elements_per_skb *
 529                             (skb_shinfo(skb)->gso_segs + 1);
 530 }
 531
 532 static struct qeth_eddp_context *
 533 qeth_eddp_create_context_generic(struct qeth_card *card, struct sk_buff *skb,
 534                                  int hdr_len)
 535 {
 536         struct qeth_eddp_context *ctx = NULL;
 537         u8 *addr;
 538         int i;
 539
 540         QETH_DBF_TEXT(trace, 5, "creddpcg");
 541         /* create the context and allocate pages */
 542         ctx = kzalloc(sizeof(struct qeth_eddp_context), GFP_ATOMIC);
 543         if (ctx == NULL){
 544                 QETH_DBF_TEXT(trace, 2, "ceddpcn1");
 545                 return NULL;
 546         }
 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 = kcalloc(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         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 = kcalloc(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         /* reset num_elements; will be incremented again in fill_buffer to
 579          * reflect number of actually used elements */
 580         ctx->num_elements = 0;
 581         return ctx;
 582 }
 583
 584 static struct qeth_eddp_context *
 585 qeth_eddp_create_context_tcp(struct qeth_card *card, struct sk_buff *skb,
 586                              struct qeth_hdr *qhdr)
 587 {
 588         struct qeth_eddp_context *ctx = NULL;
 589
 590         QETH_DBF_TEXT(trace, 5, "creddpct");
 591         if (skb->protocol == htons(ETH_P_IP))
 592                 ctx = qeth_eddp_create_context_generic(card, skb,
 593                         sizeof(struct qeth_hdr) + skb->nh.iph->ihl*4 +
 594                         skb->h.th->doff*4);
 595         else if (skb->protocol == htons(ETH_P_IPV6))
 596                 ctx = qeth_eddp_create_context_generic(card, skb,
 597                         sizeof(struct qeth_hdr) + sizeof(struct ipv6hdr) +
 598                         skb->h.th->doff*4);
 599         else
 600                 QETH_DBF_TEXT(trace, 2, "cetcpinv");
 601
 602         if (ctx == NULL) {
 603                 QETH_DBF_TEXT(trace, 2, "creddpnl");
 604                 return NULL;
 605         }
 606         if (qeth_eddp_fill_context_tcp(ctx, skb, qhdr)){
 607                 QETH_DBF_TEXT(trace, 2, "ceddptfe");
 608                 qeth_eddp_free_context(ctx);
 609                 return NULL;
 610         }
 611         atomic_set(&ctx->refcnt, 1);
 612         return ctx;
 613 }
 614
 615 struct qeth_eddp_context *
 616 qeth_eddp_create_context(struct qeth_card *card, struct sk_buff *skb,
 617                          struct qeth_hdr *qhdr)
 618 {
 619         QETH_DBF_TEXT(trace, 5, "creddpc");
 620         switch (skb->sk->sk_protocol){
 621         case IPPROTO_TCP:
 622                 return qeth_eddp_create_context_tcp(card, skb, qhdr);
 623         default:
 624                 QETH_DBF_TEXT(trace, 2, "eddpinvp");
 625         }
 626         return NULL;
 627 }