freebsd-nq/sys/netinet/tcp_lro.c
Michael Tuexen dc6ab77d66 tcp: make network epoch expectations of LRO explicit
Reviewed by:		gallatin, hselasky
MFC after:		3 days
Sponsored by:		Netflix, Inc.
Differential Revision:	https://reviews.freebsd.org/D31648
2021-08-25 17:12:36 +02:00

1956 lines
51 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2007, Myricom Inc.
* Copyright (c) 2008, Intel Corporation.
* Copyright (c) 2012 The FreeBSD Foundation
* Copyright (c) 2016-2021 Mellanox Technologies.
* All rights reserved.
*
* Portions of this software were developed by Bjoern Zeeb
* under sponsorship from the FreeBSD Foundation.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_inet.h"
#include "opt_inet6.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sockbuf.h>
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/ethernet.h>
#include <net/bpf.h>
#include <net/vnet.h>
#include <netinet/in_systm.h>
#include <netinet/in.h>
#include <netinet/ip6.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/in_pcb.h>
#include <netinet6/in6_pcb.h>
#include <netinet/tcp.h>
#include <netinet/tcp_seq.h>
#include <netinet/tcp_lro.h>
#include <netinet/tcp_var.h>
#include <netinet/tcpip.h>
#include <netinet/tcp_hpts.h>
#include <netinet/tcp_log_buf.h>
#include <netinet/udp.h>
#include <netinet6/ip6_var.h>
#include <machine/in_cksum.h>
static MALLOC_DEFINE(M_LRO, "LRO", "LRO control structures");
#define TCP_LRO_TS_OPTION \
ntohl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | \
(TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP)
static void tcp_lro_rx_done(struct lro_ctrl *lc);
static int tcp_lro_rx_common(struct lro_ctrl *lc, struct mbuf *m,
uint32_t csum, bool use_hash);
#ifdef TCPHPTS
static bool do_bpf_strip_and_compress(struct inpcb *, struct lro_ctrl *,
struct lro_entry *, struct mbuf **, struct mbuf **, struct mbuf **, bool *, bool);
#endif
SYSCTL_NODE(_net_inet_tcp, OID_AUTO, lro, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
"TCP LRO");
static long tcplro_stacks_wanting_mbufq;
counter_u64_t tcp_inp_lro_direct_queue;
counter_u64_t tcp_inp_lro_wokeup_queue;
counter_u64_t tcp_inp_lro_compressed;
counter_u64_t tcp_inp_lro_locks_taken;
counter_u64_t tcp_extra_mbuf;
counter_u64_t tcp_would_have_but;
counter_u64_t tcp_comp_total;
counter_u64_t tcp_uncomp_total;
counter_u64_t tcp_bad_csums;
static unsigned tcp_lro_entries = TCP_LRO_ENTRIES;
SYSCTL_UINT(_net_inet_tcp_lro, OID_AUTO, entries,
CTLFLAG_RDTUN | CTLFLAG_MPSAFE, &tcp_lro_entries, 0,
"default number of LRO entries");
static uint32_t tcp_lro_cpu_set_thresh = TCP_LRO_CPU_DECLARATION_THRESH;
SYSCTL_UINT(_net_inet_tcp_lro, OID_AUTO, lro_cpu_threshold,
CTLFLAG_RDTUN | CTLFLAG_MPSAFE, &tcp_lro_cpu_set_thresh, 0,
"Number of interrups in a row on the same CPU that will make us declare an 'affinity' cpu?");
SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, fullqueue, CTLFLAG_RD,
&tcp_inp_lro_direct_queue, "Number of lro's fully queued to transport");
SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, wokeup, CTLFLAG_RD,
&tcp_inp_lro_wokeup_queue, "Number of lro's where we woke up transport via hpts");
SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, compressed, CTLFLAG_RD,
&tcp_inp_lro_compressed, "Number of lro's compressed and sent to transport");
SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, lockcnt, CTLFLAG_RD,
&tcp_inp_lro_locks_taken, "Number of lro's inp_wlocks taken");
SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, extra_mbuf, CTLFLAG_RD,
&tcp_extra_mbuf, "Number of times we had an extra compressed ack dropped into the tp");
SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, would_have_but, CTLFLAG_RD,
&tcp_would_have_but, "Number of times we would have had an extra compressed, but mget failed");
SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, with_m_ackcmp, CTLFLAG_RD,
&tcp_comp_total, "Number of mbufs queued with M_ACKCMP flags set");
SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, without_m_ackcmp, CTLFLAG_RD,
&tcp_uncomp_total, "Number of mbufs queued without M_ACKCMP");
SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, lro_badcsum, CTLFLAG_RD,
&tcp_bad_csums, "Number of packets that the common code saw with bad csums");
void
tcp_lro_reg_mbufq(void)
{
atomic_fetchadd_long(&tcplro_stacks_wanting_mbufq, 1);
}
void
tcp_lro_dereg_mbufq(void)
{
atomic_fetchadd_long(&tcplro_stacks_wanting_mbufq, -1);
}
static __inline void
tcp_lro_active_insert(struct lro_ctrl *lc, struct lro_head *bucket,
struct lro_entry *le)
{
LIST_INSERT_HEAD(&lc->lro_active, le, next);
LIST_INSERT_HEAD(bucket, le, hash_next);
}
static __inline void
tcp_lro_active_remove(struct lro_entry *le)
{
LIST_REMOVE(le, next); /* active list */
LIST_REMOVE(le, hash_next); /* hash bucket */
}
int
tcp_lro_init(struct lro_ctrl *lc)
{
return (tcp_lro_init_args(lc, NULL, tcp_lro_entries, 0));
}
int
tcp_lro_init_args(struct lro_ctrl *lc, struct ifnet *ifp,
unsigned lro_entries, unsigned lro_mbufs)
{
struct lro_entry *le;
size_t size;
unsigned i, elements;
lc->lro_bad_csum = 0;
lc->lro_queued = 0;
lc->lro_flushed = 0;
lc->lro_mbuf_count = 0;
lc->lro_mbuf_max = lro_mbufs;
lc->lro_cnt = lro_entries;
lc->lro_ackcnt_lim = TCP_LRO_ACKCNT_MAX;
lc->lro_length_lim = TCP_LRO_LENGTH_MAX;
lc->ifp = ifp;
LIST_INIT(&lc->lro_free);
LIST_INIT(&lc->lro_active);
/* create hash table to accelerate entry lookup */
if (lro_entries > lro_mbufs)
elements = lro_entries;
else
elements = lro_mbufs;
lc->lro_hash = phashinit_flags(elements, M_LRO, &lc->lro_hashsz,
HASH_NOWAIT);
if (lc->lro_hash == NULL) {
memset(lc, 0, sizeof(*lc));
return (ENOMEM);
}
/* compute size to allocate */
size = (lro_mbufs * sizeof(struct lro_mbuf_sort)) +
(lro_entries * sizeof(*le));
lc->lro_mbuf_data = (struct lro_mbuf_sort *)
malloc(size, M_LRO, M_NOWAIT | M_ZERO);
/* check for out of memory */
if (lc->lro_mbuf_data == NULL) {
free(lc->lro_hash, M_LRO);
memset(lc, 0, sizeof(*lc));
return (ENOMEM);
}
/* compute offset for LRO entries */
le = (struct lro_entry *)
(lc->lro_mbuf_data + lro_mbufs);
/* setup linked list */
for (i = 0; i != lro_entries; i++)
LIST_INSERT_HEAD(&lc->lro_free, le + i, next);
return (0);
}
struct vxlan_header {
uint32_t vxlh_flags;
uint32_t vxlh_vni;
};
static inline void *
tcp_lro_low_level_parser(void *ptr, struct lro_parser *parser, bool update_data, bool is_vxlan, int mlen)
{
const struct ether_vlan_header *eh;
void *old;
uint16_t eth_type;
if (update_data)
memset(parser, 0, sizeof(*parser));
old = ptr;
if (is_vxlan) {
const struct vxlan_header *vxh;
vxh = ptr;
ptr = (uint8_t *)ptr + sizeof(*vxh);
if (update_data) {
parser->data.vxlan_vni =
vxh->vxlh_vni & htonl(0xffffff00);
}
}
eh = ptr;
if (__predict_false(eh->evl_encap_proto == htons(ETHERTYPE_VLAN))) {
eth_type = eh->evl_proto;
if (update_data) {
/* strip priority and keep VLAN ID only */
parser->data.vlan_id = eh->evl_tag & htons(EVL_VLID_MASK);
}
/* advance to next header */
ptr = (uint8_t *)ptr + ETHER_HDR_LEN + ETHER_VLAN_ENCAP_LEN;
mlen -= (ETHER_HDR_LEN + ETHER_VLAN_ENCAP_LEN);
} else {
eth_type = eh->evl_encap_proto;
/* advance to next header */
mlen -= ETHER_HDR_LEN;
ptr = (uint8_t *)ptr + ETHER_HDR_LEN;
}
if (__predict_false(mlen <= 0))
return (NULL);
switch (eth_type) {
#ifdef INET
case htons(ETHERTYPE_IP):
parser->ip4 = ptr;
if (__predict_false(mlen < sizeof(struct ip)))
return (NULL);
/* Ensure there are no IPv4 options. */
if ((parser->ip4->ip_hl << 2) != sizeof (*parser->ip4))
break;
/* .. and the packet is not fragmented. */
if (parser->ip4->ip_off & htons(IP_MF|IP_OFFMASK))
break;
ptr = (uint8_t *)ptr + (parser->ip4->ip_hl << 2);
mlen -= sizeof(struct ip);
if (update_data) {
parser->data.s_addr.v4 = parser->ip4->ip_src;
parser->data.d_addr.v4 = parser->ip4->ip_dst;
}
switch (parser->ip4->ip_p) {
case IPPROTO_UDP:
if (__predict_false(mlen < sizeof(struct udphdr)))
return (NULL);
parser->udp = ptr;
if (update_data) {
parser->data.lro_type = LRO_TYPE_IPV4_UDP;
parser->data.s_port = parser->udp->uh_sport;
parser->data.d_port = parser->udp->uh_dport;
} else {
MPASS(parser->data.lro_type == LRO_TYPE_IPV4_UDP);
}
ptr = ((uint8_t *)ptr + sizeof(*parser->udp));
parser->total_hdr_len = (uint8_t *)ptr - (uint8_t *)old;
return (ptr);
case IPPROTO_TCP:
parser->tcp = ptr;
if (__predict_false(mlen < sizeof(struct tcphdr)))
return (NULL);
if (update_data) {
parser->data.lro_type = LRO_TYPE_IPV4_TCP;
parser->data.s_port = parser->tcp->th_sport;
parser->data.d_port = parser->tcp->th_dport;
} else {
MPASS(parser->data.lro_type == LRO_TYPE_IPV4_TCP);
}
if (__predict_false(mlen < (parser->tcp->th_off << 2)))
return (NULL);
ptr = (uint8_t *)ptr + (parser->tcp->th_off << 2);
parser->total_hdr_len = (uint8_t *)ptr - (uint8_t *)old;
return (ptr);
default:
break;
}
break;
#endif
#ifdef INET6
case htons(ETHERTYPE_IPV6):
parser->ip6 = ptr;
if (__predict_false(mlen < sizeof(struct ip6_hdr)))
return (NULL);
ptr = (uint8_t *)ptr + sizeof(*parser->ip6);
if (update_data) {
parser->data.s_addr.v6 = parser->ip6->ip6_src;
parser->data.d_addr.v6 = parser->ip6->ip6_dst;
}
mlen -= sizeof(struct ip6_hdr);
switch (parser->ip6->ip6_nxt) {
case IPPROTO_UDP:
if (__predict_false(mlen < sizeof(struct udphdr)))
return (NULL);
parser->udp = ptr;
if (update_data) {
parser->data.lro_type = LRO_TYPE_IPV6_UDP;
parser->data.s_port = parser->udp->uh_sport;
parser->data.d_port = parser->udp->uh_dport;
} else {
MPASS(parser->data.lro_type == LRO_TYPE_IPV6_UDP);
}
ptr = (uint8_t *)ptr + sizeof(*parser->udp);
parser->total_hdr_len = (uint8_t *)ptr - (uint8_t *)old;
return (ptr);
case IPPROTO_TCP:
if (__predict_false(mlen < sizeof(struct tcphdr)))
return (NULL);
parser->tcp = ptr;
if (update_data) {
parser->data.lro_type = LRO_TYPE_IPV6_TCP;
parser->data.s_port = parser->tcp->th_sport;
parser->data.d_port = parser->tcp->th_dport;
} else {
MPASS(parser->data.lro_type == LRO_TYPE_IPV6_TCP);
}
if (__predict_false(mlen < (parser->tcp->th_off << 2)))
return (NULL);
ptr = (uint8_t *)ptr + (parser->tcp->th_off << 2);
parser->total_hdr_len = (uint8_t *)ptr - (uint8_t *)old;
return (ptr);
default:
break;
}
break;
#endif
default:
break;
}
/* Invalid packet - cannot parse */
return (NULL);
}
static const int vxlan_csum = CSUM_INNER_L3_CALC | CSUM_INNER_L3_VALID |
CSUM_INNER_L4_CALC | CSUM_INNER_L4_VALID;
static inline struct lro_parser *
tcp_lro_parser(struct mbuf *m, struct lro_parser *po, struct lro_parser *pi, bool update_data)
{
void *data_ptr;
/* Try to parse outer headers first. */
data_ptr = tcp_lro_low_level_parser(m->m_data, po, update_data, false, m->m_len);
if (data_ptr == NULL || po->total_hdr_len > m->m_len)
return (NULL);
if (update_data) {
/* Store VLAN ID, if any. */
if (__predict_false(m->m_flags & M_VLANTAG)) {
po->data.vlan_id =
htons(m->m_pkthdr.ether_vtag) & htons(EVL_VLID_MASK);
}
/* Store decrypted flag, if any. */
if (__predict_false(m->m_flags & M_DECRYPTED))
po->data.lro_flags |= LRO_FLAG_DECRYPTED;
}
switch (po->data.lro_type) {
case LRO_TYPE_IPV4_UDP:
case LRO_TYPE_IPV6_UDP:
/* Check for VXLAN headers. */
if ((m->m_pkthdr.csum_flags & vxlan_csum) != vxlan_csum)
break;
/* Try to parse inner headers. */
data_ptr = tcp_lro_low_level_parser(data_ptr, pi, update_data, true,
(m->m_len - ((caddr_t)data_ptr - m->m_data)));
if (data_ptr == NULL || (pi->total_hdr_len + po->total_hdr_len) > m->m_len)
break;
/* Verify supported header types. */
switch (pi->data.lro_type) {
case LRO_TYPE_IPV4_TCP:
case LRO_TYPE_IPV6_TCP:
return (pi);
default:
break;
}
break;
case LRO_TYPE_IPV4_TCP:
case LRO_TYPE_IPV6_TCP:
if (update_data)
memset(pi, 0, sizeof(*pi));
return (po);
default:
break;
}
return (NULL);
}
static inline int
tcp_lro_trim_mbuf_chain(struct mbuf *m, const struct lro_parser *po)
{
int len;
switch (po->data.lro_type) {
#ifdef INET
case LRO_TYPE_IPV4_TCP:
len = ((uint8_t *)po->ip4 - (uint8_t *)m->m_data) +
ntohs(po->ip4->ip_len);
break;
#endif
#ifdef INET6
case LRO_TYPE_IPV6_TCP:
len = ((uint8_t *)po->ip6 - (uint8_t *)m->m_data) +
ntohs(po->ip6->ip6_plen) + sizeof(*po->ip6);
break;
#endif
default:
return (TCP_LRO_CANNOT);
}
/*
* If the frame is padded beyond the end of the IP packet,
* then trim the extra bytes off:
*/
if (__predict_true(m->m_pkthdr.len == len)) {
return (0);
} else if (m->m_pkthdr.len > len) {
m_adj(m, len - m->m_pkthdr.len);
return (0);
}
return (TCP_LRO_CANNOT);
}
static struct tcphdr *
tcp_lro_get_th(struct mbuf *m)
{
return ((struct tcphdr *)((uint8_t *)m->m_data + m->m_pkthdr.lro_tcp_h_off));
}
static void
lro_free_mbuf_chain(struct mbuf *m)
{
struct mbuf *save;
while (m) {
save = m->m_nextpkt;
m->m_nextpkt = NULL;
m_freem(m);
m = save;
}
}
void
tcp_lro_free(struct lro_ctrl *lc)
{
struct lro_entry *le;
unsigned x;
/* reset LRO free list */
LIST_INIT(&lc->lro_free);
/* free active mbufs, if any */
while ((le = LIST_FIRST(&lc->lro_active)) != NULL) {
tcp_lro_active_remove(le);
lro_free_mbuf_chain(le->m_head);
}
/* free hash table */
free(lc->lro_hash, M_LRO);
lc->lro_hash = NULL;
lc->lro_hashsz = 0;
/* free mbuf array, if any */
for (x = 0; x != lc->lro_mbuf_count; x++)
m_freem(lc->lro_mbuf_data[x].mb);
lc->lro_mbuf_count = 0;
/* free allocated memory, if any */
free(lc->lro_mbuf_data, M_LRO);
lc->lro_mbuf_data = NULL;
}
static uint16_t
tcp_lro_rx_csum_tcphdr(const struct tcphdr *th)
{
const uint16_t *ptr;
uint32_t csum;
uint16_t len;
csum = -th->th_sum; /* exclude checksum field */
len = th->th_off;
ptr = (const uint16_t *)th;
while (len--) {
csum += *ptr;
ptr++;
csum += *ptr;
ptr++;
}
while (csum > 0xffff)
csum = (csum >> 16) + (csum & 0xffff);
return (csum);
}
static uint16_t
tcp_lro_rx_csum_data(const struct lro_parser *pa, uint16_t tcp_csum)
{
uint32_t c;
uint16_t cs;
c = tcp_csum;
switch (pa->data.lro_type) {
#ifdef INET6
case LRO_TYPE_IPV6_TCP:
/* Compute full pseudo IPv6 header checksum. */
cs = in6_cksum_pseudo(pa->ip6, ntohs(pa->ip6->ip6_plen), pa->ip6->ip6_nxt, 0);
break;
#endif
#ifdef INET
case LRO_TYPE_IPV4_TCP:
/* Compute full pseudo IPv4 header checsum. */
cs = in_addword(ntohs(pa->ip4->ip_len) - sizeof(*pa->ip4), IPPROTO_TCP);
cs = in_pseudo(pa->ip4->ip_src.s_addr, pa->ip4->ip_dst.s_addr, htons(cs));
break;
#endif
default:
cs = 0; /* Keep compiler happy. */
break;
}
/* Complement checksum. */
cs = ~cs;
c += cs;
/* Remove TCP header checksum. */
cs = ~tcp_lro_rx_csum_tcphdr(pa->tcp);
c += cs;
/* Compute checksum remainder. */
while (c > 0xffff)
c = (c >> 16) + (c & 0xffff);
return (c);
}
static void
tcp_lro_rx_done(struct lro_ctrl *lc)
{
struct lro_entry *le;
while ((le = LIST_FIRST(&lc->lro_active)) != NULL) {
tcp_lro_active_remove(le);
tcp_lro_flush(lc, le);
}
}
void
tcp_lro_flush_inactive(struct lro_ctrl *lc, const struct timeval *timeout)
{
struct lro_entry *le, *le_tmp;
uint64_t now, tov;
struct bintime bt;
NET_EPOCH_ASSERT();
if (LIST_EMPTY(&lc->lro_active))
return;
/* get timeout time and current time in ns */
binuptime(&bt);
now = bintime2ns(&bt);
tov = ((timeout->tv_sec * 1000000000) + (timeout->tv_usec * 1000));
LIST_FOREACH_SAFE(le, &lc->lro_active, next, le_tmp) {
if (now >= (bintime2ns(&le->alloc_time) + tov)) {
tcp_lro_active_remove(le);
tcp_lro_flush(lc, le);
}
}
}
#ifdef INET
static int
tcp_lro_rx_ipv4(struct lro_ctrl *lc, struct mbuf *m, struct ip *ip4)
{
uint16_t csum;
/* Legacy IP has a header checksum that needs to be correct. */
if (m->m_pkthdr.csum_flags & CSUM_IP_CHECKED) {
if (__predict_false((m->m_pkthdr.csum_flags & CSUM_IP_VALID) == 0)) {
lc->lro_bad_csum++;
return (TCP_LRO_CANNOT);
}
} else {
csum = in_cksum_hdr(ip4);
if (__predict_false(csum != 0)) {
lc->lro_bad_csum++;
return (TCP_LRO_CANNOT);
}
}
return (0);
}
#endif
#ifdef TCPHPTS
static void
tcp_lro_log(struct tcpcb *tp, const struct lro_ctrl *lc,
const struct lro_entry *le, const struct mbuf *m,
int frm, int32_t tcp_data_len, uint32_t th_seq,
uint32_t th_ack, uint16_t th_win)
{
if (tp->t_logstate != TCP_LOG_STATE_OFF) {
union tcp_log_stackspecific log;
struct timeval tv, btv;
uint32_t cts;
cts = tcp_get_usecs(&tv);
memset(&log, 0, sizeof(union tcp_log_stackspecific));
log.u_bbr.flex8 = frm;
log.u_bbr.flex1 = tcp_data_len;
if (m)
log.u_bbr.flex2 = m->m_pkthdr.len;
else
log.u_bbr.flex2 = 0;
log.u_bbr.flex3 = le->m_head->m_pkthdr.lro_nsegs;
log.u_bbr.flex4 = le->m_head->m_pkthdr.lro_tcp_d_len;
if (le->m_head) {
log.u_bbr.flex5 = le->m_head->m_pkthdr.len;
log.u_bbr.delRate = le->m_head->m_flags;
log.u_bbr.rttProp = le->m_head->m_pkthdr.rcv_tstmp;
}
log.u_bbr.inflight = th_seq;
log.u_bbr.delivered = th_ack;
log.u_bbr.timeStamp = cts;
log.u_bbr.epoch = le->next_seq;
log.u_bbr.lt_epoch = le->ack_seq;
log.u_bbr.pacing_gain = th_win;
log.u_bbr.cwnd_gain = le->window;
log.u_bbr.lost = curcpu;
log.u_bbr.cur_del_rate = (uintptr_t)m;
log.u_bbr.bw_inuse = (uintptr_t)le->m_head;
bintime2timeval(&lc->lro_last_queue_time, &btv);
log.u_bbr.flex6 = tcp_tv_to_usectick(&btv);
log.u_bbr.flex7 = le->compressed;
log.u_bbr.pacing_gain = le->uncompressed;
if (in_epoch(net_epoch_preempt))
log.u_bbr.inhpts = 1;
else
log.u_bbr.inhpts = 0;
TCP_LOG_EVENTP(tp, NULL,
&tp->t_inpcb->inp_socket->so_rcv,
&tp->t_inpcb->inp_socket->so_snd,
TCP_LOG_LRO, 0,
0, &log, false, &tv);
}
}
#endif
static inline void
tcp_lro_assign_and_checksum_16(uint16_t *ptr, uint16_t value, uint16_t *psum)
{
uint32_t csum;
csum = 0xffff - *ptr + value;
while (csum > 0xffff)
csum = (csum >> 16) + (csum & 0xffff);
*ptr = value;
*psum = csum;
}
static uint16_t
tcp_lro_update_checksum(const struct lro_parser *pa, const struct lro_entry *le,
uint16_t payload_len, uint16_t delta_sum)
{
uint32_t csum;
uint16_t tlen;
uint16_t temp[5] = {};
switch (pa->data.lro_type) {
case LRO_TYPE_IPV4_TCP:
/* Compute new IPv4 length. */
tlen = (pa->ip4->ip_hl << 2) + (pa->tcp->th_off << 2) + payload_len;
tcp_lro_assign_and_checksum_16(&pa->ip4->ip_len, htons(tlen), &temp[0]);
/* Subtract delta from current IPv4 checksum. */
csum = pa->ip4->ip_sum + 0xffff - temp[0];
while (csum > 0xffff)
csum = (csum >> 16) + (csum & 0xffff);
tcp_lro_assign_and_checksum_16(&pa->ip4->ip_sum, csum, &temp[1]);
goto update_tcp_header;
case LRO_TYPE_IPV6_TCP:
/* Compute new IPv6 length. */
tlen = (pa->tcp->th_off << 2) + payload_len;
tcp_lro_assign_and_checksum_16(&pa->ip6->ip6_plen, htons(tlen), &temp[0]);
goto update_tcp_header;
case LRO_TYPE_IPV4_UDP:
/* Compute new IPv4 length. */
tlen = (pa->ip4->ip_hl << 2) + sizeof(*pa->udp) + payload_len;
tcp_lro_assign_and_checksum_16(&pa->ip4->ip_len, htons(tlen), &temp[0]);
/* Subtract delta from current IPv4 checksum. */
csum = pa->ip4->ip_sum + 0xffff - temp[0];
while (csum > 0xffff)
csum = (csum >> 16) + (csum & 0xffff);
tcp_lro_assign_and_checksum_16(&pa->ip4->ip_sum, csum, &temp[1]);
goto update_udp_header;
case LRO_TYPE_IPV6_UDP:
/* Compute new IPv6 length. */
tlen = sizeof(*pa->udp) + payload_len;
tcp_lro_assign_and_checksum_16(&pa->ip6->ip6_plen, htons(tlen), &temp[0]);
goto update_udp_header;
default:
return (0);
}
update_tcp_header:
/* Compute current TCP header checksum. */
temp[2] = tcp_lro_rx_csum_tcphdr(pa->tcp);
/* Incorporate the latest ACK into the TCP header. */
pa->tcp->th_ack = le->ack_seq;
pa->tcp->th_win = le->window;
/* Incorporate latest timestamp into the TCP header. */
if (le->timestamp != 0) {
uint32_t *ts_ptr;
ts_ptr = (uint32_t *)(pa->tcp + 1);
ts_ptr[1] = htonl(le->tsval);
ts_ptr[2] = le->tsecr;
}
/* Compute new TCP header checksum. */
temp[3] = tcp_lro_rx_csum_tcphdr(pa->tcp);
/* Compute new TCP checksum. */
csum = pa->tcp->th_sum + 0xffff - delta_sum +
0xffff - temp[0] + 0xffff - temp[3] + temp[2];
while (csum > 0xffff)
csum = (csum >> 16) + (csum & 0xffff);
/* Assign new TCP checksum. */
tcp_lro_assign_and_checksum_16(&pa->tcp->th_sum, csum, &temp[4]);
/* Compute all modififications affecting next checksum. */
csum = temp[0] + temp[1] + 0xffff - temp[2] +
temp[3] + temp[4] + delta_sum;
while (csum > 0xffff)
csum = (csum >> 16) + (csum & 0xffff);
/* Return delta checksum to next stage, if any. */
return (csum);
update_udp_header:
tlen = sizeof(*pa->udp) + payload_len;
/* Assign new UDP length and compute checksum delta. */
tcp_lro_assign_and_checksum_16(&pa->udp->uh_ulen, htons(tlen), &temp[2]);
/* Check if there is a UDP checksum. */
if (__predict_false(pa->udp->uh_sum != 0)) {
/* Compute new UDP checksum. */
csum = pa->udp->uh_sum + 0xffff - delta_sum +
0xffff - temp[0] + 0xffff - temp[2];
while (csum > 0xffff)
csum = (csum >> 16) + (csum & 0xffff);
/* Assign new UDP checksum. */
tcp_lro_assign_and_checksum_16(&pa->udp->uh_sum, csum, &temp[3]);
}
/* Compute all modififications affecting next checksum. */
csum = temp[0] + temp[1] + temp[2] + temp[3] + delta_sum;
while (csum > 0xffff)
csum = (csum >> 16) + (csum & 0xffff);
/* Return delta checksum to next stage, if any. */
return (csum);
}
static void
tcp_flush_out_entry(struct lro_ctrl *lc, struct lro_entry *le)
{
/* Check if we need to recompute any checksums. */
if (le->m_head->m_pkthdr.lro_nsegs > 1) {
uint16_t csum;
switch (le->inner.data.lro_type) {
case LRO_TYPE_IPV4_TCP:
csum = tcp_lro_update_checksum(&le->inner, le,
le->m_head->m_pkthdr.lro_tcp_d_len,
le->m_head->m_pkthdr.lro_tcp_d_csum);
csum = tcp_lro_update_checksum(&le->outer, NULL,
le->m_head->m_pkthdr.lro_tcp_d_len +
le->inner.total_hdr_len, csum);
le->m_head->m_pkthdr.csum_flags = CSUM_DATA_VALID |
CSUM_PSEUDO_HDR | CSUM_IP_CHECKED | CSUM_IP_VALID;
le->m_head->m_pkthdr.csum_data = 0xffff;
break;
case LRO_TYPE_IPV6_TCP:
csum = tcp_lro_update_checksum(&le->inner, le,
le->m_head->m_pkthdr.lro_tcp_d_len,
le->m_head->m_pkthdr.lro_tcp_d_csum);
csum = tcp_lro_update_checksum(&le->outer, NULL,
le->m_head->m_pkthdr.lro_tcp_d_len +
le->inner.total_hdr_len, csum);
le->m_head->m_pkthdr.csum_flags = CSUM_DATA_VALID |
CSUM_PSEUDO_HDR;
le->m_head->m_pkthdr.csum_data = 0xffff;
break;
case LRO_TYPE_NONE:
switch (le->outer.data.lro_type) {
case LRO_TYPE_IPV4_TCP:
csum = tcp_lro_update_checksum(&le->outer, le,
le->m_head->m_pkthdr.lro_tcp_d_len,
le->m_head->m_pkthdr.lro_tcp_d_csum);
le->m_head->m_pkthdr.csum_flags = CSUM_DATA_VALID |
CSUM_PSEUDO_HDR | CSUM_IP_CHECKED | CSUM_IP_VALID;
le->m_head->m_pkthdr.csum_data = 0xffff;
break;
case LRO_TYPE_IPV6_TCP:
csum = tcp_lro_update_checksum(&le->outer, le,
le->m_head->m_pkthdr.lro_tcp_d_len,
le->m_head->m_pkthdr.lro_tcp_d_csum);
le->m_head->m_pkthdr.csum_flags = CSUM_DATA_VALID |
CSUM_PSEUDO_HDR;
le->m_head->m_pkthdr.csum_data = 0xffff;
break;
default:
break;
}
break;
default:
break;
}
}
/*
* Break any chain, this is not set to NULL on the singleton
* case m_nextpkt points to m_head. Other case set them
* m_nextpkt to NULL in push_and_replace.
*/
le->m_head->m_nextpkt = NULL;
lc->lro_queued += le->m_head->m_pkthdr.lro_nsegs;
(*lc->ifp->if_input)(lc->ifp, le->m_head);
}
static void
tcp_set_entry_to_mbuf(struct lro_ctrl *lc, struct lro_entry *le,
struct mbuf *m, struct tcphdr *th)
{
uint32_t *ts_ptr;
uint16_t tcp_data_len;
uint16_t tcp_opt_len;
ts_ptr = (uint32_t *)(th + 1);
tcp_opt_len = (th->th_off << 2);
tcp_opt_len -= sizeof(*th);
/* Check if there is a timestamp option. */
if (tcp_opt_len == 0 ||
__predict_false(tcp_opt_len != TCPOLEN_TSTAMP_APPA ||
*ts_ptr != TCP_LRO_TS_OPTION)) {
/* We failed to find the timestamp option. */
le->timestamp = 0;
} else {
le->timestamp = 1;
le->tsval = ntohl(*(ts_ptr + 1));
le->tsecr = *(ts_ptr + 2);
}
tcp_data_len = m->m_pkthdr.lro_tcp_d_len;
/* Pull out TCP sequence numbers and window size. */
le->next_seq = ntohl(th->th_seq) + tcp_data_len;
le->ack_seq = th->th_ack;
le->window = th->th_win;
/* Setup new data pointers. */
le->m_head = m;
le->m_tail = m_last(m);
}
static void
tcp_push_and_replace(struct lro_ctrl *lc, struct lro_entry *le, struct mbuf *m)
{
struct lro_parser *pa;
/*
* Push up the stack of the current entry
* and replace it with "m".
*/
struct mbuf *msave;
/* Grab off the next and save it */
msave = le->m_head->m_nextpkt;
le->m_head->m_nextpkt = NULL;
/* Now push out the old entry */
tcp_flush_out_entry(lc, le);
/* Re-parse new header, should not fail. */
pa = tcp_lro_parser(m, &le->outer, &le->inner, false);
KASSERT(pa != NULL,
("tcp_push_and_replace: LRO parser failed on m=%p\n", m));
/*
* Now to replace the data properly in the entry
* we have to reset the TCP header and
* other fields.
*/
tcp_set_entry_to_mbuf(lc, le, m, pa->tcp);
/* Restore the next list */
m->m_nextpkt = msave;
}
static void
tcp_lro_mbuf_append_pkthdr(struct mbuf *m, const struct mbuf *p)
{
uint32_t csum;
if (m->m_pkthdr.lro_nsegs == 1) {
/* Compute relative checksum. */
csum = p->m_pkthdr.lro_tcp_d_csum;
} else {
/* Merge TCP data checksums. */
csum = (uint32_t)m->m_pkthdr.lro_tcp_d_csum +
(uint32_t)p->m_pkthdr.lro_tcp_d_csum;
while (csum > 0xffff)
csum = (csum >> 16) + (csum & 0xffff);
}
/* Update various counters. */
m->m_pkthdr.len += p->m_pkthdr.lro_tcp_d_len;
m->m_pkthdr.lro_tcp_d_csum = csum;
m->m_pkthdr.lro_tcp_d_len += p->m_pkthdr.lro_tcp_d_len;
m->m_pkthdr.lro_nsegs += p->m_pkthdr.lro_nsegs;
}
static void
tcp_lro_condense(struct lro_ctrl *lc, struct lro_entry *le)
{
/*
* Walk through the mbuf chain we
* have on tap and compress/condense
* as required.
*/
uint32_t *ts_ptr;
struct mbuf *m;
struct tcphdr *th;
uint32_t tcp_data_len_total;
uint32_t tcp_data_seg_total;
uint16_t tcp_data_len;
uint16_t tcp_opt_len;
/*
* First we must check the lead (m_head)
* we must make sure that it is *not*
* something that should be sent up
* right away (sack etc).
*/
again:
m = le->m_head->m_nextpkt;
if (m == NULL) {
/* Just one left. */
return;
}
th = tcp_lro_get_th(m);
tcp_opt_len = (th->th_off << 2);
tcp_opt_len -= sizeof(*th);
ts_ptr = (uint32_t *)(th + 1);
if (tcp_opt_len != 0 && __predict_false(tcp_opt_len != TCPOLEN_TSTAMP_APPA ||
*ts_ptr != TCP_LRO_TS_OPTION)) {
/*
* Its not the timestamp. We can't
* use this guy as the head.
*/
le->m_head->m_nextpkt = m->m_nextpkt;
tcp_push_and_replace(lc, le, m);
goto again;
}
if ((th->th_flags & ~(TH_ACK | TH_PUSH)) != 0) {
/*
* Make sure that previously seen segements/ACKs are delivered
* before this segment, e.g. FIN.
*/
le->m_head->m_nextpkt = m->m_nextpkt;
tcp_push_and_replace(lc, le, m);
goto again;
}
while((m = le->m_head->m_nextpkt) != NULL) {
/*
* condense m into le, first
* pull m out of the list.
*/
le->m_head->m_nextpkt = m->m_nextpkt;
m->m_nextpkt = NULL;
/* Setup my data */
tcp_data_len = m->m_pkthdr.lro_tcp_d_len;
th = tcp_lro_get_th(m);
ts_ptr = (uint32_t *)(th + 1);
tcp_opt_len = (th->th_off << 2);
tcp_opt_len -= sizeof(*th);
tcp_data_len_total = le->m_head->m_pkthdr.lro_tcp_d_len + tcp_data_len;
tcp_data_seg_total = le->m_head->m_pkthdr.lro_nsegs + m->m_pkthdr.lro_nsegs;
if (tcp_data_seg_total >= lc->lro_ackcnt_lim ||
tcp_data_len_total >= lc->lro_length_lim) {
/* Flush now if appending will result in overflow. */
tcp_push_and_replace(lc, le, m);
goto again;
}
if (tcp_opt_len != 0 &&
__predict_false(tcp_opt_len != TCPOLEN_TSTAMP_APPA ||
*ts_ptr != TCP_LRO_TS_OPTION)) {
/*
* Maybe a sack in the new one? We need to
* start all over after flushing the
* current le. We will go up to the beginning
* and flush it (calling the replace again possibly
* or just returning).
*/
tcp_push_and_replace(lc, le, m);
goto again;
}
if ((th->th_flags & ~(TH_ACK | TH_PUSH)) != 0) {
tcp_push_and_replace(lc, le, m);
goto again;
}
if (tcp_opt_len != 0) {
uint32_t tsval = ntohl(*(ts_ptr + 1));
/* Make sure timestamp values are increasing. */
if (TSTMP_GT(le->tsval, tsval)) {
tcp_push_and_replace(lc, le, m);
goto again;
}
le->tsval = tsval;
le->tsecr = *(ts_ptr + 2);
}
/* Try to append the new segment. */
if (__predict_false(ntohl(th->th_seq) != le->next_seq ||
(tcp_data_len == 0 &&
le->ack_seq == th->th_ack &&
le->window == th->th_win))) {
/* Out of order packet or duplicate ACK. */
tcp_push_and_replace(lc, le, m);
goto again;
}
if (tcp_data_len != 0 ||
SEQ_GT(ntohl(th->th_ack), ntohl(le->ack_seq))) {
le->next_seq += tcp_data_len;
le->ack_seq = th->th_ack;
le->window = th->th_win;
} else if (th->th_ack == le->ack_seq) {
le->window = WIN_MAX(le->window, th->th_win);
}
if (tcp_data_len == 0) {
m_freem(m);
continue;
}
/* Merge TCP data checksum and length to head mbuf. */
tcp_lro_mbuf_append_pkthdr(le->m_head, m);
/*
* Adjust the mbuf so that m_data points to the first byte of
* the ULP payload. Adjust the mbuf to avoid complications and
* append new segment to existing mbuf chain.
*/
m_adj(m, m->m_pkthdr.len - tcp_data_len);
m_demote_pkthdr(m);
le->m_tail->m_next = m;
le->m_tail = m_last(m);
}
}
#ifdef TCPHPTS
static void
tcp_queue_pkts(struct inpcb *inp, struct tcpcb *tp, struct lro_entry *le)
{
INP_WLOCK_ASSERT(inp);
if (tp->t_in_pkt == NULL) {
/* Nothing yet there */
tp->t_in_pkt = le->m_head;
tp->t_tail_pkt = le->m_last_mbuf;
} else {
/* Already some there */
tp->t_tail_pkt->m_nextpkt = le->m_head;
tp->t_tail_pkt = le->m_last_mbuf;
}
le->m_head = NULL;
le->m_last_mbuf = NULL;
}
static struct mbuf *
tcp_lro_get_last_if_ackcmp(struct lro_ctrl *lc, struct lro_entry *le,
struct inpcb *inp, int32_t *new_m)
{
struct tcpcb *tp;
struct mbuf *m;
tp = intotcpcb(inp);
if (__predict_false(tp == NULL))
return (NULL);
/* Look at the last mbuf if any in queue */
m = tp->t_tail_pkt;
if (m != NULL && (m->m_flags & M_ACKCMP) != 0) {
if (M_TRAILINGSPACE(m) >= sizeof(struct tcp_ackent)) {
tcp_lro_log(tp, lc, le, NULL, 23, 0, 0, 0, 0);
*new_m = 0;
counter_u64_add(tcp_extra_mbuf, 1);
return (m);
} else {
/* Mark we ran out of space */
inp->inp_flags2 |= INP_MBUF_L_ACKS;
}
}
/* Decide mbuf size. */
if (inp->inp_flags2 & INP_MBUF_L_ACKS)
m = m_getcl(M_NOWAIT, MT_DATA, M_ACKCMP | M_PKTHDR);
else
m = m_gethdr(M_NOWAIT, MT_DATA);
if (__predict_false(m == NULL)) {
counter_u64_add(tcp_would_have_but, 1);
return (NULL);
}
counter_u64_add(tcp_comp_total, 1);
m->m_flags |= M_ACKCMP;
*new_m = 1;
return (m);
}
static struct inpcb *
tcp_lro_lookup(struct ifnet *ifp, struct lro_parser *pa)
{
struct inpcb *inp;
switch (pa->data.lro_type) {
#ifdef INET6
case LRO_TYPE_IPV6_TCP:
inp = in6_pcblookup(&V_tcbinfo,
&pa->data.s_addr.v6,
pa->data.s_port,
&pa->data.d_addr.v6,
pa->data.d_port,
INPLOOKUP_WLOCKPCB,
ifp);
break;
#endif
#ifdef INET
case LRO_TYPE_IPV4_TCP:
inp = in_pcblookup(&V_tcbinfo,
pa->data.s_addr.v4,
pa->data.s_port,
pa->data.d_addr.v4,
pa->data.d_port,
INPLOOKUP_WLOCKPCB,
ifp);
break;
#endif
default:
inp = NULL;
break;
}
return (inp);
}
static inline bool
tcp_lro_ack_valid(struct mbuf *m, struct tcphdr *th, uint32_t **ppts, bool *other_opts)
{
/*
* This function returns two bits of valuable information.
* a) Is what is present capable of being ack-compressed,
* we can ack-compress if there is no options or just
* a timestamp option, and of course the th_flags must
* be correct as well.
* b) Our other options present such as SACK. This is
* used to determine if we want to wakeup or not.
*/
bool ret = true;
switch (th->th_off << 2) {
case (sizeof(*th) + TCPOLEN_TSTAMP_APPA):
*ppts = (uint32_t *)(th + 1);
/* Check if we have only one timestamp option. */
if (**ppts == TCP_LRO_TS_OPTION)
*other_opts = false;
else {
*other_opts = true;
ret = false;
}
break;
case (sizeof(*th)):
/* No options. */
*ppts = NULL;
*other_opts = false;
break;
default:
*ppts = NULL;
*other_opts = true;
ret = false;
break;
}
/* For ACKCMP we only accept ACK, PUSH, ECE and CWR. */
if ((th->th_flags & ~(TH_ACK | TH_PUSH | TH_ECE | TH_CWR)) != 0)
ret = false;
/* If it has data on it we cannot compress it */
if (m->m_pkthdr.lro_tcp_d_len)
ret = false;
/* ACK flag must be set. */
if (!(th->th_flags & TH_ACK))
ret = false;
return (ret);
}
static int
tcp_lro_flush_tcphpts(struct lro_ctrl *lc, struct lro_entry *le)
{
struct inpcb *inp;
struct tcpcb *tp;
struct mbuf **pp, *cmp, *mv_to;
bool bpf_req, should_wake;
/* Check if packet doesn't belongs to our network interface. */
if ((tcplro_stacks_wanting_mbufq == 0) ||
(le->outer.data.vlan_id != 0) ||
(le->inner.data.lro_type != LRO_TYPE_NONE))
return (TCP_LRO_CANNOT);
#ifdef INET6
/*
* Be proactive about unspecified IPv6 address in source. As
* we use all-zero to indicate unbounded/unconnected pcb,
* unspecified IPv6 address can be used to confuse us.
*
* Note that packets with unspecified IPv6 destination is
* already dropped in ip6_input.
*/
if (__predict_false(le->outer.data.lro_type == LRO_TYPE_IPV6_TCP &&
IN6_IS_ADDR_UNSPECIFIED(&le->outer.data.s_addr.v6)))
return (TCP_LRO_CANNOT);
if (__predict_false(le->inner.data.lro_type == LRO_TYPE_IPV6_TCP &&
IN6_IS_ADDR_UNSPECIFIED(&le->inner.data.s_addr.v6)))
return (TCP_LRO_CANNOT);
#endif
/* Lookup inp, if any. */
inp = tcp_lro_lookup(lc->ifp,
(le->inner.data.lro_type == LRO_TYPE_NONE) ? &le->outer : &le->inner);
if (inp == NULL)
return (TCP_LRO_CANNOT);
counter_u64_add(tcp_inp_lro_locks_taken, 1);
/* Get TCP control structure. */
tp = intotcpcb(inp);
/* Check if the inp is dead, Jim. */
if (tp == NULL ||
(inp->inp_flags & (INP_DROPPED | INP_TIMEWAIT)) ||
(inp->inp_flags2 & INP_FREED)) {
INP_WUNLOCK(inp);
return (TCP_LRO_CANNOT);
}
if ((inp->inp_irq_cpu_set == 0) && (lc->lro_cpu_is_set == 1)) {
inp->inp_irq_cpu = lc->lro_last_cpu;
inp->inp_irq_cpu_set = 1;
}
/* Check if the transport doesn't support the needed optimizations. */
if ((inp->inp_flags2 & (INP_SUPPORTS_MBUFQ | INP_MBUF_ACKCMP)) == 0) {
INP_WUNLOCK(inp);
return (TCP_LRO_CANNOT);
}
if (inp->inp_flags2 & INP_MBUF_QUEUE_READY)
should_wake = false;
else
should_wake = true;
/* Check if packets should be tapped to BPF. */
bpf_req = bpf_peers_present(lc->ifp->if_bpf);
/* Strip and compress all the incoming packets. */
cmp = NULL;
for (pp = &le->m_head; *pp != NULL; ) {
mv_to = NULL;
if (do_bpf_strip_and_compress(inp, lc, le, pp,
&cmp, &mv_to, &should_wake, bpf_req ) == false) {
/* Advance to next mbuf. */
pp = &(*pp)->m_nextpkt;
} else if (mv_to != NULL) {
/* We are asked to move pp up */
pp = &mv_to->m_nextpkt;
}
}
/* Update "m_last_mbuf", if any. */
if (pp == &le->m_head)
le->m_last_mbuf = *pp;
else
le->m_last_mbuf = __containerof(pp, struct mbuf, m_nextpkt);
/* Check if any data mbufs left. */
if (le->m_head != NULL) {
counter_u64_add(tcp_inp_lro_direct_queue, 1);
tcp_lro_log(tp, lc, le, NULL, 22, 1,
inp->inp_flags2, inp->inp_in_input, 1);
tcp_queue_pkts(inp, tp, le);
}
if (should_wake) {
/* Wakeup */
counter_u64_add(tcp_inp_lro_wokeup_queue, 1);
if ((*tp->t_fb->tfb_do_queued_segments)(inp->inp_socket, tp, 0))
inp = NULL;
}
if (inp != NULL)
INP_WUNLOCK(inp);
return (0); /* Success. */
}
#endif
void
tcp_lro_flush(struct lro_ctrl *lc, struct lro_entry *le)
{
/* Only optimise if there are multiple packets waiting. */
#ifdef TCPHPTS
int error;
#endif
NET_EPOCH_ASSERT();
#ifdef TCPHPTS
CURVNET_SET(lc->ifp->if_vnet);
error = tcp_lro_flush_tcphpts(lc, le);
CURVNET_RESTORE();
if (error != 0) {
#endif
tcp_lro_condense(lc, le);
tcp_flush_out_entry(lc, le);
#ifdef TCPHPTS
}
#endif
lc->lro_flushed++;
bzero(le, sizeof(*le));
LIST_INSERT_HEAD(&lc->lro_free, le, next);
}
#ifdef HAVE_INLINE_FLSLL
#define tcp_lro_msb_64(x) (1ULL << (flsll(x) - 1))
#else
static inline uint64_t
tcp_lro_msb_64(uint64_t x)
{
x |= (x >> 1);
x |= (x >> 2);
x |= (x >> 4);
x |= (x >> 8);
x |= (x >> 16);
x |= (x >> 32);
return (x & ~(x >> 1));
}
#endif
/*
* The tcp_lro_sort() routine is comparable to qsort(), except it has
* a worst case complexity limit of O(MIN(N,64)*N), where N is the
* number of elements to sort and 64 is the number of sequence bits
* available. The algorithm is bit-slicing the 64-bit sequence number,
* sorting one bit at a time from the most significant bit until the
* least significant one, skipping the constant bits. This is
* typically called a radix sort.
*/
static void
tcp_lro_sort(struct lro_mbuf_sort *parray, uint32_t size)
{
struct lro_mbuf_sort temp;
uint64_t ones;
uint64_t zeros;
uint32_t x;
uint32_t y;
repeat:
/* for small arrays insertion sort is faster */
if (size <= 12) {
for (x = 1; x < size; x++) {
temp = parray[x];
for (y = x; y > 0 && temp.seq < parray[y - 1].seq; y--)
parray[y] = parray[y - 1];
parray[y] = temp;
}
return;
}
/* compute sequence bits which are constant */
ones = 0;
zeros = 0;
for (x = 0; x != size; x++) {
ones |= parray[x].seq;
zeros |= ~parray[x].seq;
}
/* compute bits which are not constant into "ones" */
ones &= zeros;
if (ones == 0)
return;
/* pick the most significant bit which is not constant */
ones = tcp_lro_msb_64(ones);
/*
* Move entries having cleared sequence bits to the beginning
* of the array:
*/
for (x = y = 0; y != size; y++) {
/* skip set bits */
if (parray[y].seq & ones)
continue;
/* swap entries */
temp = parray[x];
parray[x] = parray[y];
parray[y] = temp;
x++;
}
KASSERT(x != 0 && x != size, ("Memory is corrupted\n"));
/* sort zeros */
tcp_lro_sort(parray, x);
/* sort ones */
parray += x;
size -= x;
goto repeat;
}
void
tcp_lro_flush_all(struct lro_ctrl *lc)
{
uint64_t seq;
uint64_t nseq;
unsigned x;
NET_EPOCH_ASSERT();
/* check if no mbufs to flush */
if (lc->lro_mbuf_count == 0)
goto done;
if (lc->lro_cpu_is_set == 0) {
if (lc->lro_last_cpu == curcpu) {
lc->lro_cnt_of_same_cpu++;
/* Have we reached the threshold to declare a cpu? */
if (lc->lro_cnt_of_same_cpu > tcp_lro_cpu_set_thresh)
lc->lro_cpu_is_set = 1;
} else {
lc->lro_last_cpu = curcpu;
lc->lro_cnt_of_same_cpu = 0;
}
}
CURVNET_SET(lc->ifp->if_vnet);
/* get current time */
binuptime(&lc->lro_last_queue_time);
/* sort all mbufs according to stream */
tcp_lro_sort(lc->lro_mbuf_data, lc->lro_mbuf_count);
/* input data into LRO engine, stream by stream */
seq = 0;
for (x = 0; x != lc->lro_mbuf_count; x++) {
struct mbuf *mb;
/* get mbuf */
mb = lc->lro_mbuf_data[x].mb;
/* get sequence number, masking away the packet index */
nseq = lc->lro_mbuf_data[x].seq & (-1ULL << 24);
/* check for new stream */
if (seq != nseq) {
seq = nseq;
/* flush active streams */
tcp_lro_rx_done(lc);
}
/* add packet to LRO engine */
if (tcp_lro_rx_common(lc, mb, 0, false) != 0) {
/* input packet to network layer */
(*lc->ifp->if_input)(lc->ifp, mb);
lc->lro_queued++;
lc->lro_flushed++;
}
}
CURVNET_RESTORE();
done:
/* flush active streams */
tcp_lro_rx_done(lc);
#ifdef TCPHPTS
tcp_run_hpts();
#endif
lc->lro_mbuf_count = 0;
}
#ifdef TCPHPTS
static void
build_ack_entry(struct tcp_ackent *ae, struct tcphdr *th, struct mbuf *m,
uint32_t *ts_ptr, uint16_t iptos)
{
/*
* Given a TCP ACK, summarize it down into the small TCP ACK
* entry.
*/
ae->timestamp = m->m_pkthdr.rcv_tstmp;
if (m->m_flags & M_TSTMP_LRO)
ae->flags = TSTMP_LRO;
else if (m->m_flags & M_TSTMP)
ae->flags = TSTMP_HDWR;
ae->seq = ntohl(th->th_seq);
ae->ack = ntohl(th->th_ack);
ae->flags |= th->th_flags;
if (ts_ptr != NULL) {
ae->ts_value = ntohl(ts_ptr[1]);
ae->ts_echo = ntohl(ts_ptr[2]);
ae->flags |= HAS_TSTMP;
}
ae->win = ntohs(th->th_win);
ae->codepoint = iptos;
}
/*
* Do BPF tap for either ACK_CMP packets or MBUF QUEUE type packets
* and strip all, but the IPv4/IPv6 header.
*/
static bool
do_bpf_strip_and_compress(struct inpcb *inp, struct lro_ctrl *lc,
struct lro_entry *le, struct mbuf **pp, struct mbuf **cmp, struct mbuf **mv_to,
bool *should_wake, bool bpf_req)
{
union {
void *ptr;
struct ip *ip4;
struct ip6_hdr *ip6;
} l3;
struct mbuf *m;
struct mbuf *nm;
struct tcphdr *th;
struct tcp_ackent *ack_ent;
uint32_t *ts_ptr;
int32_t n_mbuf;
bool other_opts, can_compress;
uint8_t lro_type;
uint16_t iptos;
int tcp_hdr_offset;
int idx;
/* Get current mbuf. */
m = *pp;
/* Let the BPF see the packet */
if (__predict_false(bpf_req))
ETHER_BPF_MTAP(lc->ifp, m);
tcp_hdr_offset = m->m_pkthdr.lro_tcp_h_off;
lro_type = le->inner.data.lro_type;
switch (lro_type) {
case LRO_TYPE_NONE:
lro_type = le->outer.data.lro_type;
switch (lro_type) {
case LRO_TYPE_IPV4_TCP:
tcp_hdr_offset -= sizeof(*le->outer.ip4);
m->m_pkthdr.lro_etype = ETHERTYPE_IP;
break;
case LRO_TYPE_IPV6_TCP:
tcp_hdr_offset -= sizeof(*le->outer.ip6);
m->m_pkthdr.lro_etype = ETHERTYPE_IPV6;
break;
default:
goto compressed;
}
break;
case LRO_TYPE_IPV4_TCP:
tcp_hdr_offset -= sizeof(*le->outer.ip4);
m->m_pkthdr.lro_etype = ETHERTYPE_IP;
break;
case LRO_TYPE_IPV6_TCP:
tcp_hdr_offset -= sizeof(*le->outer.ip6);
m->m_pkthdr.lro_etype = ETHERTYPE_IPV6;
break;
default:
goto compressed;
}
MPASS(tcp_hdr_offset >= 0);
m_adj(m, tcp_hdr_offset);
m->m_flags |= M_LRO_EHDRSTRP;
m->m_flags &= ~M_ACKCMP;
m->m_pkthdr.lro_tcp_h_off -= tcp_hdr_offset;
th = tcp_lro_get_th(m);
th->th_sum = 0; /* TCP checksum is valid. */
/* Check if ACK can be compressed */
can_compress = tcp_lro_ack_valid(m, th, &ts_ptr, &other_opts);
/* Now lets look at the should wake states */
if ((other_opts == true) &&
((inp->inp_flags2 & INP_DONT_SACK_QUEUE) == 0)) {
/*
* If there are other options (SACK?) and the
* tcp endpoint has not expressly told us it does
* not care about SACKS, then we should wake up.
*/
*should_wake = true;
}
/* Is the ack compressable? */
if (can_compress == false)
goto done;
/* Does the TCP endpoint support ACK compression? */
if ((inp->inp_flags2 & INP_MBUF_ACKCMP) == 0)
goto done;
/* Lets get the TOS/traffic class field */
l3.ptr = mtod(m, void *);
switch (lro_type) {
case LRO_TYPE_IPV4_TCP:
iptos = l3.ip4->ip_tos;
break;
case LRO_TYPE_IPV6_TCP:
iptos = IPV6_TRAFFIC_CLASS(l3.ip6);
break;
default:
iptos = 0; /* Keep compiler happy. */
break;
}
/* Now lets get space if we don't have some already */
if (*cmp == NULL) {
new_one:
nm = tcp_lro_get_last_if_ackcmp(lc, le, inp, &n_mbuf);
if (__predict_false(nm == NULL))
goto done;
*cmp = nm;
if (n_mbuf) {
/*
* Link in the new cmp ack to our in-order place,
* first set our cmp ack's next to where we are.
*/
nm->m_nextpkt = m;
(*pp) = nm;
/*
* Set it up so mv_to is advanced to our
* compressed ack. This way the caller can
* advance pp to the right place.
*/
*mv_to = nm;
/*
* Advance it here locally as well.
*/
pp = &nm->m_nextpkt;
}
} else {
/* We have one already we are working on */
nm = *cmp;
if (M_TRAILINGSPACE(nm) < sizeof(struct tcp_ackent)) {
/* We ran out of space */
inp->inp_flags2 |= INP_MBUF_L_ACKS;
goto new_one;
}
}
MPASS(M_TRAILINGSPACE(nm) >= sizeof(struct tcp_ackent));
counter_u64_add(tcp_inp_lro_compressed, 1);
le->compressed++;
/* We can add in to the one on the tail */
ack_ent = mtod(nm, struct tcp_ackent *);
idx = (nm->m_len / sizeof(struct tcp_ackent));
build_ack_entry(&ack_ent[idx], th, m, ts_ptr, iptos);
/* Bump the size of both pkt-hdr and len */
nm->m_len += sizeof(struct tcp_ackent);
nm->m_pkthdr.len += sizeof(struct tcp_ackent);
compressed:
/* Advance to next mbuf before freeing. */
*pp = m->m_nextpkt;
m->m_nextpkt = NULL;
m_freem(m);
return (true);
done:
counter_u64_add(tcp_uncomp_total, 1);
le->uncompressed++;
return (false);
}
#endif
static struct lro_head *
tcp_lro_rx_get_bucket(struct lro_ctrl *lc, struct mbuf *m, struct lro_parser *parser)
{
u_long hash;
if (M_HASHTYPE_ISHASH(m)) {
hash = m->m_pkthdr.flowid;
} else {
for (unsigned i = hash = 0; i != LRO_RAW_ADDRESS_MAX; i++)
hash += parser->data.raw[i];
}
return (&lc->lro_hash[hash % lc->lro_hashsz]);
}
static int
tcp_lro_rx_common(struct lro_ctrl *lc, struct mbuf *m, uint32_t csum, bool use_hash)
{
struct lro_parser pi; /* inner address data */
struct lro_parser po; /* outer address data */
struct lro_parser *pa; /* current parser for TCP stream */
struct lro_entry *le;
struct lro_head *bucket;
struct tcphdr *th;
int tcp_data_len;
int tcp_opt_len;
int error;
uint16_t tcp_data_sum;
#ifdef INET
/* Quickly decide if packet cannot be LRO'ed */
if (__predict_false(V_ipforwarding != 0))
return (TCP_LRO_CANNOT);
#endif
#ifdef INET6
/* Quickly decide if packet cannot be LRO'ed */
if (__predict_false(V_ip6_forwarding != 0))
return (TCP_LRO_CANNOT);
#endif
if (((m->m_pkthdr.csum_flags & (CSUM_DATA_VALID | CSUM_PSEUDO_HDR)) !=
((CSUM_DATA_VALID | CSUM_PSEUDO_HDR))) ||
(m->m_pkthdr.csum_data != 0xffff)) {
/*
* The checksum either did not have hardware offload
* or it was a bad checksum. We can't LRO such
* a packet.
*/
counter_u64_add(tcp_bad_csums, 1);
return (TCP_LRO_CANNOT);
}
/* We expect a contiguous header [eh, ip, tcp]. */
pa = tcp_lro_parser(m, &po, &pi, true);
if (__predict_false(pa == NULL))
return (TCP_LRO_NOT_SUPPORTED);
/* We don't expect any padding. */
error = tcp_lro_trim_mbuf_chain(m, pa);
if (__predict_false(error != 0))
return (error);
#ifdef INET
switch (pa->data.lro_type) {
case LRO_TYPE_IPV4_TCP:
error = tcp_lro_rx_ipv4(lc, m, pa->ip4);
if (__predict_false(error != 0))
return (error);
break;
default:
break;
}
#endif
/* If no hardware or arrival stamp on the packet add timestamp */
if ((m->m_flags & (M_TSTMP_LRO | M_TSTMP)) == 0) {
m->m_pkthdr.rcv_tstmp = bintime2ns(&lc->lro_last_queue_time);
m->m_flags |= M_TSTMP_LRO;
}
/* Get pointer to TCP header. */
th = pa->tcp;
/* Don't process SYN packets. */
if (__predict_false(th->th_flags & TH_SYN))
return (TCP_LRO_CANNOT);
/* Get total TCP header length and compute payload length. */
tcp_opt_len = (th->th_off << 2);
tcp_data_len = m->m_pkthdr.len - ((uint8_t *)th -
(uint8_t *)m->m_data) - tcp_opt_len;
tcp_opt_len -= sizeof(*th);
/* Don't process invalid TCP headers. */
if (__predict_false(tcp_opt_len < 0 || tcp_data_len < 0))
return (TCP_LRO_CANNOT);
/* Compute TCP data only checksum. */
if (tcp_data_len == 0)
tcp_data_sum = 0; /* no data, no checksum */
else if (__predict_false(csum != 0))
tcp_data_sum = tcp_lro_rx_csum_data(pa, ~csum);
else
tcp_data_sum = tcp_lro_rx_csum_data(pa, ~th->th_sum);
/* Save TCP info in mbuf. */
m->m_nextpkt = NULL;
m->m_pkthdr.rcvif = lc->ifp;
m->m_pkthdr.lro_tcp_d_csum = tcp_data_sum;
m->m_pkthdr.lro_tcp_d_len = tcp_data_len;
m->m_pkthdr.lro_tcp_h_off = ((uint8_t *)th - (uint8_t *)m->m_data);
m->m_pkthdr.lro_nsegs = 1;
/* Get hash bucket. */
if (!use_hash) {
bucket = &lc->lro_hash[0];
} else {
bucket = tcp_lro_rx_get_bucket(lc, m, pa);
}
/* Try to find a matching previous segment. */
LIST_FOREACH(le, bucket, hash_next) {
/* Compare addresses and ports. */
if (lro_address_compare(&po.data, &le->outer.data) == false ||
lro_address_compare(&pi.data, &le->inner.data) == false)
continue;
/* Check if no data and old ACK. */
if (tcp_data_len == 0 &&
SEQ_LT(ntohl(th->th_ack), ntohl(le->ack_seq))) {
m_freem(m);
return (0);
}
/* Mark "m" in the last spot. */
le->m_last_mbuf->m_nextpkt = m;
/* Now set the tail to "m". */
le->m_last_mbuf = m;
return (0);
}
/* Try to find an empty slot. */
if (LIST_EMPTY(&lc->lro_free))
return (TCP_LRO_NO_ENTRIES);
/* Start a new segment chain. */
le = LIST_FIRST(&lc->lro_free);
LIST_REMOVE(le, next);
tcp_lro_active_insert(lc, bucket, le);
/* Make sure the headers are set. */
le->inner = pi;
le->outer = po;
/* Store time this entry was allocated. */
le->alloc_time = lc->lro_last_queue_time;
tcp_set_entry_to_mbuf(lc, le, m, th);
/* Now set the tail to "m". */
le->m_last_mbuf = m;
return (0);
}
int
tcp_lro_rx(struct lro_ctrl *lc, struct mbuf *m, uint32_t csum)
{
int error;
if (((m->m_pkthdr.csum_flags & (CSUM_DATA_VALID | CSUM_PSEUDO_HDR)) !=
((CSUM_DATA_VALID | CSUM_PSEUDO_HDR))) ||
(m->m_pkthdr.csum_data != 0xffff)) {
/*
* The checksum either did not have hardware offload
* or it was a bad checksum. We can't LRO such
* a packet.
*/
counter_u64_add(tcp_bad_csums, 1);
return (TCP_LRO_CANNOT);
}
/* get current time */
binuptime(&lc->lro_last_queue_time);
CURVNET_SET(lc->ifp->if_vnet);
error = tcp_lro_rx_common(lc, m, csum, true);
CURVNET_RESTORE();
return (error);
}
void
tcp_lro_queue_mbuf(struct lro_ctrl *lc, struct mbuf *mb)
{
NET_EPOCH_ASSERT();
/* sanity checks */
if (__predict_false(lc->ifp == NULL || lc->lro_mbuf_data == NULL ||
lc->lro_mbuf_max == 0)) {
/* packet drop */
m_freem(mb);
return;
}
/* check if packet is not LRO capable */
if (__predict_false((lc->ifp->if_capenable & IFCAP_LRO) == 0)) {
/* input packet to network layer */
(*lc->ifp->if_input) (lc->ifp, mb);
return;
}
/* create sequence number */
lc->lro_mbuf_data[lc->lro_mbuf_count].seq =
(((uint64_t)M_HASHTYPE_GET(mb)) << 56) |
(((uint64_t)mb->m_pkthdr.flowid) << 24) |
((uint64_t)lc->lro_mbuf_count);
/* enter mbuf */
lc->lro_mbuf_data[lc->lro_mbuf_count].mb = mb;
/* flush if array is full */
if (__predict_false(++lc->lro_mbuf_count == lc->lro_mbuf_max))
tcp_lro_flush_all(lc);
}
/* end */