Commit 187625e1 authored by Alexander Aring's avatar Alexander Aring Committed by Marcel Holtmann
Browse files

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



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

Reviewed-by: default avatarStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: default avatarAlexander Aring <alex.aring@gmail.com>
Signed-off-by: default avatarMarcel Holtmann <marcel@holtmann.org>
parent 0c434968

include/net/6lowpan.h

+0 −113
Original line number Diff line number Diff line
@@ -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

net/ieee802154/6lowpan/tx.c

+11 −7
Original line number Diff line number Diff line
@@ -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 @@ lowpan_xmit_fragmented(struct sk_buff *skb, struct net_device *ldev, 
	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;

	}