diff options
Diffstat (limited to 'net/ipv4/inet_lro.c')
-rw-r--r-- | net/ipv4/inet_lro.c | 374 |
1 files changed, 0 insertions, 374 deletions
diff --git a/net/ipv4/inet_lro.c b/net/ipv4/inet_lro.c deleted file mode 100644 index f17ea49..0000000 --- a/net/ipv4/inet_lro.c +++ /dev/null @@ -1,374 +0,0 @@ -/* - * 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); |