ieee802154: 6lowpan: remove tx full-size calc workaround

This patch removes a workaround for datagram_size calculation while
doing fragmentation on transmit.

Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

diff --git a/include/net/6lowpan.h b/include/net/6lowpan.h
index 3509841..eeae5eb 100644 (file)
--- a/include/net/6lowpan.h
+++ b/include/net/6lowpan.h
@@ -299,119 +299,6 @@ static inline void lowpan_push_hc_data(u8 **hc_ptr, const void *data,
        *hc_ptr += len;
 }
 
-static inline u8 lowpan_addr_mode_size(const u8 addr_mode)
-{
-       static const u8 addr_sizes[] = {
-               [LOWPAN_IPHC_ADDR_00] = 16,
-               [LOWPAN_IPHC_ADDR_01] = 8,
-               [LOWPAN_IPHC_ADDR_02] = 2,
-               [LOWPAN_IPHC_ADDR_03] = 0,
-       };
-       return addr_sizes[addr_mode];
-}
-
-static inline u8 lowpan_next_hdr_size(const u8 h_enc, u16 *uncomp_header)
-{
-       u8 ret = 1;
-
-       if ((h_enc & LOWPAN_NHC_UDP_MASK) == LOWPAN_NHC_UDP_ID) {
-               *uncomp_header += sizeof(struct udphdr);
-
-               switch (h_enc & LOWPAN_NHC_UDP_CS_P_11) {
-               case LOWPAN_NHC_UDP_CS_P_00:
-                       ret += 4;
-                       break;
-               case LOWPAN_NHC_UDP_CS_P_01:
-               case LOWPAN_NHC_UDP_CS_P_10:
-                       ret += 3;
-                       break;
-               case LOWPAN_NHC_UDP_CS_P_11:
-                       ret++;
-                       break;
-               default:
-                       break;
-               }
-
-               if (!(h_enc & LOWPAN_NHC_UDP_CS_C))
-                       ret += 2;
-       }
-
-       return ret;
-}
-
-/**
- *     lowpan_uncompress_size - returns skb->len size with uncompressed header
- *     @skb: sk_buff with 6lowpan header inside
- *     @datagram_offset: optional to get the datagram_offset value
- *
- *     Returns the skb->len with uncompressed header
- */
-static inline u16
-lowpan_uncompress_size(const struct sk_buff *skb, u16 *dgram_offset)
-{
-       u16 ret = 2, uncomp_header = sizeof(struct ipv6hdr);
-       u8 iphc0, iphc1, h_enc;
-
-       iphc0 = skb_network_header(skb)[0];
-       iphc1 = skb_network_header(skb)[1];
-
-       switch ((iphc0 & LOWPAN_IPHC_TF) >> 3) {
-       case 0:
-               ret += 4;
-               break;
-       case 1:
-               ret += 3;
-               break;
-       case 2:
-               ret++;
-               break;
-       default:
-               break;
-       }
-
-       if (!(iphc0 & LOWPAN_IPHC_NH_C))
-               ret++;
-
-       if (!(iphc0 & 0x03))
-               ret++;
-
-       ret += lowpan_addr_mode_size((iphc1 & LOWPAN_IPHC_SAM) >>
-                                    LOWPAN_IPHC_SAM_BIT);
-
-       if (iphc1 & LOWPAN_IPHC_M) {
-               switch ((iphc1 & LOWPAN_IPHC_DAM_11) >>
-                       LOWPAN_IPHC_DAM_BIT) {
-               case LOWPAN_IPHC_DAM_00:
-                       ret += 16;
-                       break;
-               case LOWPAN_IPHC_DAM_01:
-                       ret += 6;
-                       break;
-               case LOWPAN_IPHC_DAM_10:
-                       ret += 4;
-                       break;
-               case LOWPAN_IPHC_DAM_11:
-                       ret++;
-                       break;
-               default:
-                       break;
-               }
-       } else {
-               ret += lowpan_addr_mode_size((iphc1 & LOWPAN_IPHC_DAM_11) >>
-                                            LOWPAN_IPHC_DAM_BIT);
-       }
-
-       if (iphc0 & LOWPAN_IPHC_NH_C) {
-               h_enc = skb_network_header(skb)[ret];
-               ret += lowpan_next_hdr_size(h_enc, &uncomp_header);
-       }
-
-       if (dgram_offset)
-               *dgram_offset = uncomp_header;
-
-       return skb->len + uncomp_header - ret;
-}
-
 void lowpan_netdev_setup(struct net_device *dev, enum lowpan_lltypes lltype);
 
 int

diff --git a/net/ieee802154/6lowpan/tx.c b/net/ieee802154/6lowpan/tx.c
index 9a2147e..54939d0 100644 (file)
--- a/net/ieee802154/6lowpan/tx.c
+++ b/net/ieee802154/6lowpan/tx.c
@@ -123,16 +123,14 @@ lowpan_xmit_fragment(struct sk_buff *skb, const struct ieee802154_hdr *wpan_hdr,
 
 static int
 lowpan_xmit_fragmented(struct sk_buff *skb, struct net_device *ldev,
-                      const struct ieee802154_hdr *wpan_hdr)
+                      const struct ieee802154_hdr *wpan_hdr, u16 dgram_size,
+                      u16 dgram_offset)
 {
-       u16 dgram_size, dgram_offset;
        __be16 frag_tag;
        u8 frag_hdr[5];
        int frag_cap, frag_len, payload_cap, rc;
        int skb_unprocessed, skb_offset;
 
-       dgram_size = lowpan_uncompress_size(skb, &dgram_offset) -
-                    skb->mac_len;
        frag_tag = htons(lowpan_dev_info(ldev)->fragment_tag);
        lowpan_dev_info(ldev)->fragment_tag++;
 
@@ -187,7 +185,8 @@ err:
        return rc;
 }
 
-static int lowpan_header(struct sk_buff *skb, struct net_device *ldev)
+static int lowpan_header(struct sk_buff *skb, struct net_device *ldev,
+                        u16 *dgram_size, u16 *dgram_offset)
 {
        struct wpan_dev *wpan_dev = lowpan_dev_info(ldev)->wdev->ieee802154_ptr;
        struct ieee802154_addr sa, da;
@@ -201,7 +200,10 @@ static int lowpan_header(struct sk_buff *skb, struct net_device *ldev)
        daddr = &info.daddr.u.extended_addr;
        saddr = &info.saddr.u.extended_addr;
 
+       *dgram_size = skb->len;
        lowpan_header_compress(skb, ldev, ETH_P_IPV6, daddr, saddr, skb->len);
+       /* dgram_offset = (saved bytes after compression) + lowpan header len */
+       *dgram_offset = (*dgram_size - skb->len) + skb_network_header_len(skb);
 
        cb->type = IEEE802154_FC_TYPE_DATA;
 
@@ -234,6 +236,7 @@ netdev_tx_t lowpan_xmit(struct sk_buff *skb, struct net_device *ldev)
 {
        struct ieee802154_hdr wpan_hdr;
        int max_single, ret;
+       u16 dgram_size, dgram_offset;
 
        pr_debug("package xmit\n");
 
@@ -244,7 +247,7 @@ netdev_tx_t lowpan_xmit(struct sk_buff *skb, struct net_device *ldev)
        if (!skb)
                return NET_XMIT_DROP;
 
-       ret = lowpan_header(skb, ldev);
+       ret = lowpan_header(skb, ldev, &dgram_size, &dgram_offset);
        if (ret < 0) {
                kfree_skb(skb);
                return NET_XMIT_DROP;
@@ -264,7 +267,8 @@ netdev_tx_t lowpan_xmit(struct sk_buff *skb, struct net_device *ldev)
                netdev_tx_t rc;
 
                pr_debug("frame is too big, fragmentation is needed\n");
-               rc = lowpan_xmit_fragmented(skb, ldev, &wpan_hdr);
+               rc = lowpan_xmit_fragmented(skb, ldev, &wpan_hdr, dgram_size,
+                                           dgram_offset);
 
                return rc < 0 ? NET_XMIT_DROP : rc;
        }