drivers/s390/net/qeth_tso.h

   1 /*
   2  * linux/drivers/s390/net/qeth_tso.h ($Revision: 1.7 $)
   3  *
   4  * Header file for qeth TCP Segmentation Offload support.
   5  *
   6  * Copyright 2004 IBM Corporation
   7  *
   8  *    Author(s): Frank Pavlic <pavlic@de.ibm.com>
   9  *
  10  *    $Revision: 1.7 $   $Date: 2005/05/04 20:19:18 $
  11  *
  12  */
  13 #ifndef __QETH_TSO_H__
  14 #define __QETH_TSO_H__
  15
  16 #include <linux/skbuff.h>
  17 #include <linux/tcp.h>
  18 #include <linux/ip.h>
  19 #include <linux/ipv6.h>
  20 #include <net/ip6_checksum.h>
  21 #include "qeth.h"
  22 #include "qeth_mpc.h"
  23
  24
  25 static inline struct qeth_hdr_tso *
  26 qeth_tso_prepare_skb(struct qeth_card *card, struct sk_buff **skb)
  27 {
  28         QETH_DBF_TEXT(trace, 5, "tsoprsk");
  29         return qeth_push_skb(card, skb, sizeof(struct qeth_hdr_tso));
  30 }
  31
  32 /**
  33  * fill header for a TSO packet
  34  */
  35 static inline void
  36 qeth_tso_fill_header(struct qeth_card *card, struct sk_buff *skb)
  37 {
  38         struct qeth_hdr_tso *hdr;
  39         struct tcphdr *tcph;
  40         struct iphdr *iph;
  41
  42         QETH_DBF_TEXT(trace, 5, "tsofhdr");
  43
  44         hdr  = (struct qeth_hdr_tso *) skb->data;
  45         iph  = skb->nh.iph;
  46         tcph = skb->h.th;
  47         /*fix header to TSO values ...*/
  48         hdr->hdr.hdr.l3.id = QETH_HEADER_TYPE_TSO;
  49         /*set values which are fix for the first approach ...*/
  50         hdr->ext.hdr_tot_len = (__u16) sizeof(struct qeth_hdr_ext_tso);
  51         hdr->ext.imb_hdr_no  = 1;
  52         hdr->ext.hdr_type    = 1;
  53         hdr->ext.hdr_version = 1;
  54         hdr->ext.hdr_len     = 28;
  55         /*insert non-fix values */
  56         hdr->ext.mss = skb_shinfo(skb)->tso_size;
  57         hdr->ext.dg_hdr_len = (__u16)(iph->ihl*4 + tcph->doff*4);
  58         hdr->ext.payload_len = (__u16)(skb->len - hdr->ext.dg_hdr_len -
  59                                        sizeof(struct qeth_hdr_tso));
  60 }
  61
  62 /**
  63  * change some header values as requested by hardware
  64  */
  65 static inline void
  66 qeth_tso_set_tcpip_header(struct qeth_card *card, struct sk_buff *skb)
  67 {
  68         struct iphdr *iph;
  69         struct ipv6hdr *ip6h;
  70         struct tcphdr *tcph;
  71
  72         iph  = skb->nh.iph;
  73         ip6h = skb->nh.ipv6h;
  74         tcph = skb->h.th;
  75
  76         tcph->check = 0;
  77         if (skb->protocol == ETH_P_IPV6) {
  78                 ip6h->payload_len = 0;
  79                 tcph->check = ~csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
  80                                                0, IPPROTO_TCP, 0);
  81                 return;
  82         }
  83         /*OSA want us to set these values ...*/
  84         tcph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr,
  85                                          0, IPPROTO_TCP, 0);
  86         iph->tot_len = 0;
  87         iph->check = 0;
  88 }
  89
  90 static inline int
  91 qeth_tso_prepare_packet(struct qeth_card *card, struct sk_buff *skb,
  92                         int ipv, int cast_type)
  93 {
  94         struct qeth_hdr_tso *hdr;
  95
  96         QETH_DBF_TEXT(trace, 5, "tsoprep");
  97
  98         hdr = (struct qeth_hdr_tso *) qeth_tso_prepare_skb(card, &skb);
  99         if (hdr == NULL) {
 100                 QETH_DBF_TEXT(trace, 4, "tsoperr");
 101                 return -ENOMEM;
 102         }
 103         memset(hdr, 0, sizeof(struct qeth_hdr_tso));
 104         /*fill first 32 bytes of  qdio header as used
 105          *FIXME: TSO has two struct members
 106          * with different names but same size
 107          * */
 108         qeth_fill_header(card, &hdr->hdr, skb, ipv, cast_type);
 109         qeth_tso_fill_header(card, skb);
 110         qeth_tso_set_tcpip_header(card, skb);
 111         return 0;
 112 }
 113
 114 static inline void
 115 __qeth_fill_buffer_frag(struct sk_buff *skb, struct qdio_buffer *buffer,
 116                         int is_tso, int *next_element_to_fill)
 117 {
 118         struct skb_frag_struct *frag;
 119         int fragno;
 120         unsigned long addr;
 121         int element, cnt, dlen;
 122
 123         fragno = skb_shinfo(skb)->nr_frags;
 124         element = *next_element_to_fill;
 125         dlen = 0;
 126
 127         if (is_tso)
 128                 buffer->element[element].flags =
 129                         SBAL_FLAGS_MIDDLE_FRAG;
 130         else
 131                 buffer->element[element].flags =
 132                         SBAL_FLAGS_FIRST_FRAG;
 133         if ( (dlen = (skb->len - skb->data_len)) ) {
 134                 buffer->element[element].addr = skb->data;
 135                 buffer->element[element].length = dlen;
 136                 element++;
 137         }
 138         for (cnt = 0; cnt < fragno; cnt++) {
 139                 frag = &skb_shinfo(skb)->frags[cnt];
 140                 addr = (page_to_pfn(frag->page) << PAGE_SHIFT) +
 141                         frag->page_offset;
 142                 buffer->element[element].addr = (char *)addr;
 143                 buffer->element[element].length = frag->size;
 144                 if (cnt < (fragno - 1))
 145                         buffer->element[element].flags =
 146                                 SBAL_FLAGS_MIDDLE_FRAG;
 147                 else
 148                         buffer->element[element].flags =
 149                                 SBAL_FLAGS_LAST_FRAG;
 150                 element++;
 151         }
 152         *next_element_to_fill = element;
 153 }
 154 #endif /* __QETH_TSO_H__ */