+++ /dev/null
-/*
- * linux/include/linux/inet_lro.h
- *
- * Large Receive Offload (ipv4 / tcp)
- *
- * (C) Copyright IBM Corp. 2007
- *
- * Authors:
- * Jan-Bernd Themann <themann@de.ibm.com>
- * Christoph Raisch <raisch@de.ibm.com>
- *
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2, or (at your option)
- * any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-#ifndef __INET_LRO_H_
-#define __INET_LRO_H_
-
-#include <net/ip.h>
-#include <net/tcp.h>
-
-/*
- * LRO statistics
- */
-
-struct net_lro_stats {
- unsigned long aggregated;
- unsigned long flushed;
- unsigned long no_desc;
-};
-
-/*
- * LRO descriptor for a tcp session
- */
-struct net_lro_desc {
- struct sk_buff *parent;
- struct sk_buff *last_skb;
- struct skb_frag_struct *next_frag;
- struct iphdr *iph;
- struct tcphdr *tcph;
- __wsum data_csum;
- __be32 tcp_rcv_tsecr;
- __be32 tcp_rcv_tsval;
- __be32 tcp_ack;
- u32 tcp_next_seq;
- u32 skb_tot_frags_len;
- u16 ip_tot_len;
- u16 tcp_saw_tstamp; /* timestamps enabled */
- __be16 tcp_window;
- int pkt_aggr_cnt; /* counts aggregated packets */
- int vlan_packet;
- int mss;
- int active;
-};
-
-/*
- * Large Receive Offload (LRO) Manager
- *
- * Fields must be set by driver
- */
-
-struct net_lro_mgr {
- struct net_device *dev;
- struct net_lro_stats stats;
-
- /* LRO features */
- unsigned long features;
-#define LRO_F_NAPI 1 /* Pass packets to stack via NAPI */
-#define LRO_F_EXTRACT_VLAN_ID 2 /* Set flag if VLAN IDs are extracted
- from received packets and eth protocol
- is still ETH_P_8021Q */
-
- /*
- * Set for generated SKBs that are not added to
- * the frag list in fragmented mode
- */
- u32 ip_summed;
- u32 ip_summed_aggr; /* Set in aggregated SKBs: CHECKSUM_UNNECESSARY
- * or CHECKSUM_NONE */
-
- int max_desc; /* Max number of LRO descriptors */
- int max_aggr; /* Max number of LRO packets to be aggregated */
-
- int frag_align_pad; /* Padding required to properly align layer 3
- * headers in generated skb when using frags */
-
- struct net_lro_desc *lro_arr; /* Array of LRO descriptors */
-
- /*
- * Optimized driver functions
- *
- * get_skb_header: returns tcp and ip header for packet in SKB
- */
- int (*get_skb_header)(struct sk_buff *skb, void **ip_hdr,
- void **tcpudp_hdr, u64 *hdr_flags, void *priv);
-
- /* hdr_flags: */
-#define LRO_IPV4 1 /* ip_hdr is IPv4 header */
-#define LRO_TCP 2 /* tcpudp_hdr is TCP header */
-
- /*
- * get_frag_header: returns mac, tcp and ip header for packet in SKB
- *
- * @hdr_flags: Indicate what kind of LRO has to be done
- * (IPv4/IPv6/TCP/UDP)
- */
- int (*get_frag_header)(struct skb_frag_struct *frag, void **mac_hdr,
- void **ip_hdr, void **tcpudp_hdr, u64 *hdr_flags,
- void *priv);
-};
-
-/*
- * Processes a SKB
- *
- * @lro_mgr: LRO manager to use
- * @skb: SKB to aggregate
- * @priv: Private data that may be used by driver functions
- * (for example get_tcp_ip_hdr)
- */
-
-void lro_receive_skb(struct net_lro_mgr *lro_mgr,
- struct sk_buff *skb,
- void *priv);
-/*
- * Forward all aggregated SKBs held by lro_mgr to network stack
- */
-
-void lro_flush_all(struct net_lro_mgr *lro_mgr);
-
-#endif
+++ /dev/null
-/*
- * linux/net/ipv4/inet_lro.c
- *
- * Large Receive Offload (ipv4 / tcp)
- *
- * (C) Copyright IBM Corp. 2007
- *
- * Authors:
- * Jan-Bernd Themann <themann@de.ibm.com>
- * Christoph Raisch <raisch@de.ibm.com>
- *
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2, or (at your option)
- * any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-
-#include <linux/module.h>
-#include <linux/if_vlan.h>
-#include <linux/inet_lro.h>
-#include <net/checksum.h>
-
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Jan-Bernd Themann <themann@de.ibm.com>");
-MODULE_DESCRIPTION("Large Receive Offload (ipv4 / tcp)");
-
-#define TCP_HDR_LEN(tcph) (tcph->doff << 2)
-#define IP_HDR_LEN(iph) (iph->ihl << 2)
-#define TCP_PAYLOAD_LENGTH(iph, tcph) \
- (ntohs(iph->tot_len) - IP_HDR_LEN(iph) - TCP_HDR_LEN(tcph))
-
-#define IPH_LEN_WO_OPTIONS 5
-#define TCPH_LEN_WO_OPTIONS 5
-#define TCPH_LEN_W_TIMESTAMP 8
-
-#define LRO_MAX_PG_HLEN 64
-
-#define LRO_INC_STATS(lro_mgr, attr) { lro_mgr->stats.attr++; }
-
-/*
- * Basic tcp checks whether packet is suitable for LRO
- */
-
-static int lro_tcp_ip_check(const struct iphdr *iph, const struct tcphdr *tcph,
- int len, const struct net_lro_desc *lro_desc)
-{
- /* check ip header: don't aggregate padded frames */
- if (ntohs(iph->tot_len) != len)
- return -1;
-
- if (TCP_PAYLOAD_LENGTH(iph, tcph) == 0)
- return -1;
-
- if (iph->ihl != IPH_LEN_WO_OPTIONS)
- return -1;
-
- if (tcph->cwr || tcph->ece || tcph->urg || !tcph->ack ||
- tcph->rst || tcph->syn || tcph->fin)
- return -1;
-
- if (INET_ECN_is_ce(ipv4_get_dsfield(iph)))
- return -1;
-
- if (tcph->doff != TCPH_LEN_WO_OPTIONS &&
- tcph->doff != TCPH_LEN_W_TIMESTAMP)
- return -1;
-
- /* check tcp options (only timestamp allowed) */
- if (tcph->doff == TCPH_LEN_W_TIMESTAMP) {
- __be32 *topt = (__be32 *)(tcph + 1);
-
- if (*topt != htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16)
- | (TCPOPT_TIMESTAMP << 8)
- | TCPOLEN_TIMESTAMP))
- return -1;
-
- /* timestamp should be in right order */
- topt++;
- if (lro_desc && after(ntohl(lro_desc->tcp_rcv_tsval),
- ntohl(*topt)))
- return -1;
-
- /* timestamp reply should not be zero */
- topt++;
- if (*topt == 0)
- return -1;
- }
-
- return 0;
-}
-
-static void lro_update_tcp_ip_header(struct net_lro_desc *lro_desc)
-{
- struct iphdr *iph = lro_desc->iph;
- struct tcphdr *tcph = lro_desc->tcph;
- __be32 *p;
- __wsum tcp_hdr_csum;
-
- tcph->ack_seq = lro_desc->tcp_ack;
- tcph->window = lro_desc->tcp_window;
-
- if (lro_desc->tcp_saw_tstamp) {
- p = (__be32 *)(tcph + 1);
- *(p+2) = lro_desc->tcp_rcv_tsecr;
- }
-
- csum_replace2(&iph->check, iph->tot_len, htons(lro_desc->ip_tot_len));
- iph->tot_len = htons(lro_desc->ip_tot_len);
-
- tcph->check = 0;
- tcp_hdr_csum = csum_partial(tcph, TCP_HDR_LEN(tcph), 0);
- lro_desc->data_csum = csum_add(lro_desc->data_csum, tcp_hdr_csum);
- tcph->check = csum_tcpudp_magic(iph->saddr, iph->daddr,
- lro_desc->ip_tot_len -
- IP_HDR_LEN(iph), IPPROTO_TCP,
- lro_desc->data_csum);
-}
-
-static __wsum lro_tcp_data_csum(struct iphdr *iph, struct tcphdr *tcph, int len)
-{
- __wsum tcp_csum;
- __wsum tcp_hdr_csum;
- __wsum tcp_ps_hdr_csum;
-
- tcp_csum = ~csum_unfold(tcph->check);
- tcp_hdr_csum = csum_partial(tcph, TCP_HDR_LEN(tcph), tcp_csum);
-
- tcp_ps_hdr_csum = csum_tcpudp_nofold(iph->saddr, iph->daddr,
- len + TCP_HDR_LEN(tcph),
- IPPROTO_TCP, 0);
-
- return csum_sub(csum_sub(tcp_csum, tcp_hdr_csum),
- tcp_ps_hdr_csum);
-}
-
-static void lro_init_desc(struct net_lro_desc *lro_desc, struct sk_buff *skb,
- struct iphdr *iph, struct tcphdr *tcph)
-{
- int nr_frags;
- __be32 *ptr;
- u32 tcp_data_len = TCP_PAYLOAD_LENGTH(iph, tcph);
-
- nr_frags = skb_shinfo(skb)->nr_frags;
- lro_desc->parent = skb;
- lro_desc->next_frag = &(skb_shinfo(skb)->frags[nr_frags]);
- lro_desc->iph = iph;
- lro_desc->tcph = tcph;
- lro_desc->tcp_next_seq = ntohl(tcph->seq) + tcp_data_len;
- lro_desc->tcp_ack = tcph->ack_seq;
- lro_desc->tcp_window = tcph->window;
-
- lro_desc->pkt_aggr_cnt = 1;
- lro_desc->ip_tot_len = ntohs(iph->tot_len);
-
- if (tcph->doff == 8) {
- ptr = (__be32 *)(tcph+1);
- lro_desc->tcp_saw_tstamp = 1;
- lro_desc->tcp_rcv_tsval = *(ptr+1);
- lro_desc->tcp_rcv_tsecr = *(ptr+2);
- }
-
- lro_desc->mss = tcp_data_len;
- lro_desc->active = 1;
-
- lro_desc->data_csum = lro_tcp_data_csum(iph, tcph,
- tcp_data_len);
-}
-
-static inline void lro_clear_desc(struct net_lro_desc *lro_desc)
-{
- memset(lro_desc, 0, sizeof(struct net_lro_desc));
-}
-
-static void lro_add_common(struct net_lro_desc *lro_desc, struct iphdr *iph,
- struct tcphdr *tcph, int tcp_data_len)
-{
- struct sk_buff *parent = lro_desc->parent;
- __be32 *topt;
-
- lro_desc->pkt_aggr_cnt++;
- lro_desc->ip_tot_len += tcp_data_len;
- lro_desc->tcp_next_seq += tcp_data_len;
- lro_desc->tcp_window = tcph->window;
- lro_desc->tcp_ack = tcph->ack_seq;
-
- /* don't update tcp_rcv_tsval, would not work with PAWS */
- if (lro_desc->tcp_saw_tstamp) {
- topt = (__be32 *) (tcph + 1);
- lro_desc->tcp_rcv_tsecr = *(topt + 2);
- }
-
- lro_desc->data_csum = csum_block_add(lro_desc->data_csum,
- lro_tcp_data_csum(iph, tcph,
- tcp_data_len),
- parent->len);
-
- parent->len += tcp_data_len;
- parent->data_len += tcp_data_len;
- if (tcp_data_len > lro_desc->mss)
- lro_desc->mss = tcp_data_len;
-}
-
-static void lro_add_packet(struct net_lro_desc *lro_desc, struct sk_buff *skb,
- struct iphdr *iph, struct tcphdr *tcph)
-{
- struct sk_buff *parent = lro_desc->parent;
- int tcp_data_len = TCP_PAYLOAD_LENGTH(iph, tcph);
-
- lro_add_common(lro_desc, iph, tcph, tcp_data_len);
-
- skb_pull(skb, (skb->len - tcp_data_len));
- parent->truesize += skb->truesize;
-
- if (lro_desc->last_skb)
- lro_desc->last_skb->next = skb;
- else
- skb_shinfo(parent)->frag_list = skb;
-
- lro_desc->last_skb = skb;
-}
-
-
-static int lro_check_tcp_conn(struct net_lro_desc *lro_desc,
- struct iphdr *iph,
- struct tcphdr *tcph)
-{
- if ((lro_desc->iph->saddr != iph->saddr) ||
- (lro_desc->iph->daddr != iph->daddr) ||
- (lro_desc->tcph->source != tcph->source) ||
- (lro_desc->tcph->dest != tcph->dest))
- return -1;
- return 0;
-}
-
-static struct net_lro_desc *lro_get_desc(struct net_lro_mgr *lro_mgr,
- struct net_lro_desc *lro_arr,
- struct iphdr *iph,
- struct tcphdr *tcph)
-{
- struct net_lro_desc *lro_desc = NULL;
- struct net_lro_desc *tmp;
- int max_desc = lro_mgr->max_desc;
- int i;
-
- for (i = 0; i < max_desc; i++) {
- tmp = &lro_arr[i];
- if (tmp->active)
- if (!lro_check_tcp_conn(tmp, iph, tcph)) {
- lro_desc = tmp;
- goto out;
- }
- }
-
- for (i = 0; i < max_desc; i++) {
- if (!lro_arr[i].active) {
- lro_desc = &lro_arr[i];
- goto out;
- }
- }
-
- LRO_INC_STATS(lro_mgr, no_desc);
-out:
- return lro_desc;
-}
-
-static void lro_flush(struct net_lro_mgr *lro_mgr,
- struct net_lro_desc *lro_desc)
-{
- if (lro_desc->pkt_aggr_cnt > 1)
- lro_update_tcp_ip_header(lro_desc);
-
- skb_shinfo(lro_desc->parent)->gso_size = lro_desc->mss;
-
- if (lro_mgr->features & LRO_F_NAPI)
- netif_receive_skb(lro_desc->parent);
- else
- netif_rx(lro_desc->parent);
-
- LRO_INC_STATS(lro_mgr, flushed);
- lro_clear_desc(lro_desc);
-}
-
-static int __lro_proc_skb(struct net_lro_mgr *lro_mgr, struct sk_buff *skb,
- void *priv)
-{
- struct net_lro_desc *lro_desc;
- struct iphdr *iph;
- struct tcphdr *tcph;
- u64 flags;
- int vlan_hdr_len = 0;
-
- if (!lro_mgr->get_skb_header ||
- lro_mgr->get_skb_header(skb, (void *)&iph, (void *)&tcph,
- &flags, priv))
- goto out;
-
- if (!(flags & LRO_IPV4) || !(flags & LRO_TCP))
- goto out;
-
- lro_desc = lro_get_desc(lro_mgr, lro_mgr->lro_arr, iph, tcph);
- if (!lro_desc)
- goto out;
-
- if ((skb->protocol == htons(ETH_P_8021Q)) &&
- !(lro_mgr->features & LRO_F_EXTRACT_VLAN_ID))
- vlan_hdr_len = VLAN_HLEN;
-
- if (!lro_desc->active) { /* start new lro session */
- if (lro_tcp_ip_check(iph, tcph, skb->len - vlan_hdr_len, NULL))
- goto out;
-
- skb->ip_summed = lro_mgr->ip_summed_aggr;
- lro_init_desc(lro_desc, skb, iph, tcph);
- LRO_INC_STATS(lro_mgr, aggregated);
- return 0;
- }
-
- if (lro_desc->tcp_next_seq != ntohl(tcph->seq))
- goto out2;
-
- if (lro_tcp_ip_check(iph, tcph, skb->len, lro_desc))
- goto out2;
-
- lro_add_packet(lro_desc, skb, iph, tcph);
- LRO_INC_STATS(lro_mgr, aggregated);
-
- if ((lro_desc->pkt_aggr_cnt >= lro_mgr->max_aggr) ||
- lro_desc->parent->len > (0xFFFF - lro_mgr->dev->mtu))
- lro_flush(lro_mgr, lro_desc);
-
- return 0;
-
-out2: /* send aggregated SKBs to stack */
- lro_flush(lro_mgr, lro_desc);
-
-out:
- return 1;
-}
-
-void lro_receive_skb(struct net_lro_mgr *lro_mgr,
- struct sk_buff *skb,
- void *priv)
-{
- if (__lro_proc_skb(lro_mgr, skb, priv)) {
- if (lro_mgr->features & LRO_F_NAPI)
- netif_receive_skb(skb);
- else
- netif_rx(skb);
- }
-}
-EXPORT_SYMBOL(lro_receive_skb);
-
-void lro_flush_all(struct net_lro_mgr *lro_mgr)
-{
- int i;
- struct net_lro_desc *lro_desc = lro_mgr->lro_arr;
-
- for (i = 0; i < lro_mgr->max_desc; i++) {
- if (lro_desc[i].active)
- lro_flush(lro_mgr, &lro_desc[i]);
- }
-}
-EXPORT_SYMBOL(lro_flush_all);
projects / cascardo / linux.git / commitdiff