* [PATCH v3 5/7] sctp: delay as much as possible skb_linearize
2016-06-02 18:05 [PATCH v3 0/7] sctp: Add GSO support Marcelo Ricardo Leitner
` (3 preceding siblings ...)
2016-06-02 18:05 ` [PATCH v3 4/7] skbuff: introduce skb_gso_validate_mtu Marcelo Ricardo Leitner
@ 2016-06-02 18:05 ` Marcelo Ricardo Leitner
2016-06-02 18:05 ` [PATCH v3 6/7] sctp: Add GSO support Marcelo Ricardo Leitner
` (2 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: Marcelo Ricardo Leitner @ 2016-06-02 18:05 UTC (permalink / raw)
To: netdev
Cc: linux-sctp, Xin Long, Neil Horman, David Laight, Vlad Yasevich,
Alexander Duyck, Daniel Borkmann, Florian Westphal, Eric Dumazet
This patch is a preparation for the GSO one. In order to successfully
handle GSO packets on rx path we must not call skb_linearize, otherwise
it defeats any gain GSO may have had.
This patch thus delays as much as possible the call to skb_linearize,
leaving it to sctp_inq_pop() moment. For that the sanity checks
performed now know how to deal with fragments.
One positive side-effect of this is that if the socket is backlogged it
will have the chance of doing it on backlog processing instead of
during softirq.
With this move, it's evident that a check for non-linearity in
sctp_inq_pop was ineffective and is now removed. Note that a similar
check is performed a bit below this one.
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Tested-by: Xin Long <lucien.xin@gmail.com>
---
net/sctp/input.c | 45 +++++++++++++++++++++++++--------------------
net/sctp/inqueue.c | 29 ++++++++++++++++++-----------
2 files changed, 43 insertions(+), 31 deletions(-)
diff --git a/net/sctp/input.c b/net/sctp/input.c
index a701527a9480faff1b8d91257e1dbf3c0f09ed68..5cff2546c3dd6d3823b5a28bac1e72880cd57756 100644
--- a/net/sctp/input.c
+++ b/net/sctp/input.c
@@ -112,7 +112,6 @@ int sctp_rcv(struct sk_buff *skb)
struct sctp_ep_common *rcvr;
struct sctp_transport *transport = NULL;
struct sctp_chunk *chunk;
- struct sctphdr *sh;
union sctp_addr src;
union sctp_addr dest;
int family;
@@ -124,15 +123,18 @@ int sctp_rcv(struct sk_buff *skb)
__SCTP_INC_STATS(net, SCTP_MIB_INSCTPPACKS);
- if (skb_linearize(skb))
+ /* If packet is too small to contain a single chunk, let's not
+ * waste time on it anymore.
+ */
+ if (skb->len < sizeof(struct sctphdr) + sizeof(struct sctp_chunkhdr) +
+ skb_transport_offset(skb))
goto discard_it;
- sh = sctp_hdr(skb);
+ if (!pskb_may_pull(skb, sizeof(struct sctphdr)))
+ goto discard_it;
- /* Pull up the IP and SCTP headers. */
+ /* Pull up the IP header. */
__skb_pull(skb, skb_transport_offset(skb));
- if (skb->len < sizeof(struct sctphdr))
- goto discard_it;
skb->csum_valid = 0; /* Previous value not applicable */
if (skb_csum_unnecessary(skb))
@@ -141,11 +143,7 @@ int sctp_rcv(struct sk_buff *skb)
goto discard_it;
skb->csum_valid = 1;
- skb_pull(skb, sizeof(struct sctphdr));
-
- /* Make sure we at least have chunk headers worth of data left. */
- if (skb->len < sizeof(struct sctp_chunkhdr))
- goto discard_it;
+ __skb_pull(skb, sizeof(struct sctphdr));
family = ipver2af(ip_hdr(skb)->version);
af = sctp_get_af_specific(family);
@@ -230,7 +228,7 @@ int sctp_rcv(struct sk_buff *skb)
chunk->rcvr = rcvr;
/* Remember the SCTP header. */
- chunk->sctp_hdr = sh;
+ chunk->sctp_hdr = sctp_hdr(skb);
/* Set the source and destination addresses of the incoming chunk. */
sctp_init_addrs(chunk, &src, &dest);
@@ -660,19 +658,23 @@ out_unlock:
*/
static int sctp_rcv_ootb(struct sk_buff *skb)
{
- sctp_chunkhdr_t *ch;
- __u8 *ch_end;
-
- ch = (sctp_chunkhdr_t *) skb->data;
+ sctp_chunkhdr_t *ch, _ch;
+ int ch_end, offset = 0;
/* Scan through all the chunks in the packet. */
do {
+ /* Make sure we have at least the header there */
+ if (offset + sizeof(sctp_chunkhdr_t) > skb->len)
+ break;
+
+ ch = skb_header_pointer(skb, offset, sizeof(*ch), &_ch);
+
/* Break out if chunk length is less then minimal. */
if (ntohs(ch->length) < sizeof(sctp_chunkhdr_t))
break;
- ch_end = ((__u8 *)ch) + WORD_ROUND(ntohs(ch->length));
- if (ch_end > skb_tail_pointer(skb))
+ ch_end = offset + WORD_ROUND(ntohs(ch->length));
+ if (ch_end > skb->len)
break;
/* RFC 8.4, 2) If the OOTB packet contains an ABORT chunk, the
@@ -697,8 +699,8 @@ static int sctp_rcv_ootb(struct sk_buff *skb)
if (SCTP_CID_INIT = ch->type && (void *)ch != skb->data)
goto discard;
- ch = (sctp_chunkhdr_t *) ch_end;
- } while (ch_end < skb_tail_pointer(skb));
+ offset = ch_end;
+ } while (ch_end < skb->len);
return 0;
@@ -1173,6 +1175,9 @@ static struct sctp_association *__sctp_rcv_lookup_harder(struct net *net,
{
sctp_chunkhdr_t *ch;
+ if (skb_linearize(skb))
+ return NULL;
+
ch = (sctp_chunkhdr_t *) skb->data;
/* The code below will attempt to walk the chunk and extract
diff --git a/net/sctp/inqueue.c b/net/sctp/inqueue.c
index 9d87bba0ff1d34134093f34e4db3dc1b7e3dafd6..5ba08ceda3ab6cf61eb64c58bffb9ccd589e8664 100644
--- a/net/sctp/inqueue.c
+++ b/net/sctp/inqueue.c
@@ -130,7 +130,8 @@ struct sctp_chunk *sctp_inq_pop(struct sctp_inq *queue)
* at this time.
*/
- if ((chunk = queue->in_progress)) {
+ chunk = queue->in_progress;
+ if (chunk) {
/* There is a packet that we have been working on.
* Any post processing work to do before we move on?
*/
@@ -152,15 +153,29 @@ struct sctp_chunk *sctp_inq_pop(struct sctp_inq *queue)
if (!chunk) {
struct list_head *entry;
+next_chunk:
/* Is the queue empty? */
if (list_empty(&queue->in_chunk_list))
return NULL;
entry = queue->in_chunk_list.next;
- chunk = queue->in_progress - list_entry(entry, struct sctp_chunk, list);
+ chunk = list_entry(entry, struct sctp_chunk, list);
list_del_init(entry);
+ /* Linearize if it's not GSO */
+ if (skb_is_nonlinear(chunk->skb)) {
+ if (skb_linearize(chunk->skb)) {
+ __SCTP_INC_STATS(dev_net(chunk->skb->dev), SCTP_MIB_IN_PKT_DISCARDS);
+ sctp_chunk_free(chunk);
+ goto next_chunk;
+ }
+
+ /* Update sctp_hdr as it probably changed */
+ chunk->sctp_hdr = sctp_hdr(chunk->skb);
+ }
+
+ queue->in_progress = chunk;
+
/* This is the first chunk in the packet. */
chunk->singleton = 1;
ch = (sctp_chunkhdr_t *) chunk->skb->data;
@@ -172,14 +187,6 @@ struct sctp_chunk *sctp_inq_pop(struct sctp_inq *queue)
chunk->chunk_hdr = ch;
chunk->chunk_end = ((__u8 *)ch) + WORD_ROUND(ntohs(ch->length));
- /* In the unlikely case of an IP reassembly, the skb could be
- * non-linear. If so, update chunk_end so that it doesn't go past
- * the skb->tail.
- */
- if (unlikely(skb_is_nonlinear(chunk->skb))) {
- if (chunk->chunk_end > skb_tail_pointer(chunk->skb))
- chunk->chunk_end = skb_tail_pointer(chunk->skb);
- }
skb_pull(chunk->skb, sizeof(sctp_chunkhdr_t));
chunk->subh.v = NULL; /* Subheader is no longer valid. */
--
2.5.5
^ permalink raw reply related [flat|nested] 9+ messages in thread* [PATCH v3 6/7] sctp: Add GSO support
2016-06-02 18:05 [PATCH v3 0/7] sctp: Add GSO support Marcelo Ricardo Leitner
` (4 preceding siblings ...)
2016-06-02 18:05 ` [PATCH v3 5/7] sctp: delay as much as possible skb_linearize Marcelo Ricardo Leitner
@ 2016-06-02 18:05 ` Marcelo Ricardo Leitner
2016-06-02 18:05 ` [PATCH v3 7/7] sctp: improve debug message to also log curr pkt and new chunk size Marcelo Ricardo Leitner
2016-06-03 23:37 ` [PATCH v3 0/7] sctp: Add GSO support David Miller
7 siblings, 0 replies; 9+ messages in thread
From: Marcelo Ricardo Leitner @ 2016-06-02 18:05 UTC (permalink / raw)
To: netdev
Cc: linux-sctp, Xin Long, Neil Horman, David Laight, Vlad Yasevich,
Alexander Duyck, Daniel Borkmann, Florian Westphal, Eric Dumazet
SCTP has this pecualiarity that its packets cannot be just segmented to
(P)MTU. Its chunks must be contained in IP segments, padding respected.
So we can't just generate a big skb, set gso_size to the fragmentation
point and deliver it to IP layer.
This patch takes a different approach. SCTP will now build a skb as it
would be if it was received using GRO. That is, there will be a cover
skb with protocol headers and children ones containing the actual
segments, already segmented to a way that respects SCTP RFCs.
With that, we can tell skb_segment() to just split based on frag_list,
trusting its sizes are already in accordance.
This way SCTP can benefit from GSO and instead of passing several
packets through the stack, it can pass a single large packet.
v2:
- Added support for receiving GSO frames, as requested by Dave Miller.
- Clear skb->cb if packet is GSO (otherwise it's not used by SCTP)
- Added heuristics similar to what we have in TCP for not generating
single GSO packets that fills cwnd.
v3:
- consider sctphdr size in skb_gso_transport_seglen()
- rebased due to 5c7cdf339af5 ("gso: Remove arbitrary checks for
unsupported GSO")
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Tested-by: Xin Long <lucien.xin@gmail.com>
---
include/linux/netdev_features.h | 7 +-
include/linux/netdevice.h | 1 +
include/linux/skbuff.h | 2 +
include/net/sctp/sctp.h | 4 +
include/net/sctp/structs.h | 5 +
net/core/ethtool.c | 1 +
net/core/skbuff.c | 3 +
net/sctp/Makefile | 3 +-
net/sctp/input.c | 12 +-
net/sctp/inqueue.c | 51 +++++-
net/sctp/offload.c | 98 +++++++++++
net/sctp/output.c | 363 +++++++++++++++++++++++++++-------------
net/sctp/protocol.c | 3 +
net/sctp/socket.c | 2 +
14 files changed, 429 insertions(+), 126 deletions(-)
create mode 100644 net/sctp/offload.c
diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h
index aa7b2400f98c584d29e83f0eddf7bf13766cedd1..9c6c8ef2e9e704513cc4272b0a3ee2fec6809d46 100644
--- a/include/linux/netdev_features.h
+++ b/include/linux/netdev_features.h
@@ -53,8 +53,9 @@ enum {
* headers in software.
*/
NETIF_F_GSO_TUNNEL_REMCSUM_BIT, /* ... TUNNEL with TSO & REMCSUM */
+ NETIF_F_GSO_SCTP_BIT, /* ... SCTP fragmentation */
/**/NETIF_F_GSO_LAST = /* last bit, see GSO_MASK */
- NETIF_F_GSO_TUNNEL_REMCSUM_BIT,
+ NETIF_F_GSO_SCTP_BIT,
NETIF_F_FCOE_CRC_BIT, /* FCoE CRC32 */
NETIF_F_SCTP_CRC_BIT, /* SCTP checksum offload */
@@ -128,6 +129,7 @@ enum {
#define NETIF_F_TSO_MANGLEID __NETIF_F(TSO_MANGLEID)
#define NETIF_F_GSO_PARTIAL __NETIF_F(GSO_PARTIAL)
#define NETIF_F_GSO_TUNNEL_REMCSUM __NETIF_F(GSO_TUNNEL_REMCSUM)
+#define NETIF_F_GSO_SCTP __NETIF_F(GSO_SCTP)
#define NETIF_F_HW_VLAN_STAG_FILTER __NETIF_F(HW_VLAN_STAG_FILTER)
#define NETIF_F_HW_VLAN_STAG_RX __NETIF_F(HW_VLAN_STAG_RX)
#define NETIF_F_HW_VLAN_STAG_TX __NETIF_F(HW_VLAN_STAG_TX)
@@ -166,7 +168,8 @@ enum {
NETIF_F_FSO)
/* List of features with software fallbacks. */
-#define NETIF_F_GSO_SOFTWARE (NETIF_F_ALL_TSO | NETIF_F_UFO)
+#define NETIF_F_GSO_SOFTWARE (NETIF_F_ALL_TSO | NETIF_F_UFO | \
+ NETIF_F_GSO_SCTP)
/*
* If one device supports one of these features, then enable them
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index f45929ce815725d868261e9a2585ac53d0c8f128..fa6df2699532e4ad6deb37f1bdcfafc71d2580cb 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -4012,6 +4012,7 @@ static inline bool net_gso_ok(netdev_features_t features, int gso_type)
BUILD_BUG_ON(SKB_GSO_UDP_TUNNEL_CSUM != (NETIF_F_GSO_UDP_TUNNEL_CSUM >> NETIF_F_GSO_SHIFT));
BUILD_BUG_ON(SKB_GSO_PARTIAL != (NETIF_F_GSO_PARTIAL >> NETIF_F_GSO_SHIFT));
BUILD_BUG_ON(SKB_GSO_TUNNEL_REMCSUM != (NETIF_F_GSO_TUNNEL_REMCSUM >> NETIF_F_GSO_SHIFT));
+ BUILD_BUG_ON(SKB_GSO_SCTP != (NETIF_F_GSO_SCTP >> NETIF_F_GSO_SHIFT));
return (features & feature) = feature;
}
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index aa3f9d7e8d5ca455387efa22d4a9d3a079a56f0c..dc0fca747c5e1c5b23b1e52ce3e354667eb2a994 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -487,6 +487,8 @@ enum {
SKB_GSO_PARTIAL = 1 << 13,
SKB_GSO_TUNNEL_REMCSUM = 1 << 14,
+
+ SKB_GSO_SCTP = 1 << 15,
};
#if BITS_PER_LONG > 32
diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h
index b392ac8382f2bf0be118f797a4444cc0eb4ddeb5..632e205ca54bfe85124753e09445251056e19aa7 100644
--- a/include/net/sctp/sctp.h
+++ b/include/net/sctp/sctp.h
@@ -186,6 +186,10 @@ void sctp_assocs_proc_exit(struct net *net);
int sctp_remaddr_proc_init(struct net *net);
void sctp_remaddr_proc_exit(struct net *net);
+/*
+ * sctp/offload.c
+ */
+int sctp_offload_init(void);
/*
* Module global variables
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index 16b013a6191cf1c416e4dd1aeb1707a8569ea49b..83c5ec58b93a073fce845c453747191f23495ffb 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -566,6 +566,9 @@ struct sctp_chunk {
/* This points to the sk_buff containing the actual data. */
struct sk_buff *skb;
+ /* In case of GSO packets, this will store the head one */
+ struct sk_buff *head_skb;
+
/* These are the SCTP headers by reverse order in a packet.
* Note that some of these may happen more than once. In that
* case, we point at the "current" one, whatever that means
@@ -696,6 +699,8 @@ struct sctp_packet {
size_t overhead;
/* This is the total size of all chunks INCLUDING padding. */
size_t size;
+ /* This is the maximum size this packet may have */
+ size_t max_size;
/* The packet is destined for this transport address.
* The function we finally use to pass down to the next lower
diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index f4034817d2559babb39b06c432facf14e3347890..977489820eb957098705c9ea1674ed3092a6cfe6 100644
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -89,6 +89,7 @@ static const char netdev_features_strings[NETDEV_FEATURE_COUNT][ETH_GSTRING_LEN]
[NETIF_F_GSO_UDP_TUNNEL_BIT] = "tx-udp_tnl-segmentation",
[NETIF_F_GSO_UDP_TUNNEL_CSUM_BIT] = "tx-udp_tnl-csum-segmentation",
[NETIF_F_GSO_PARTIAL_BIT] = "tx-gso-partial",
+ [NETIF_F_GSO_SCTP_BIT] = "tx-sctp-segmentation",
[NETIF_F_FCOE_CRC_BIT] = "tx-checksum-fcoe-crc",
[NETIF_F_SCTP_CRC_BIT] = "tx-checksum-sctp",
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 5ca562b56ec39d39e1225d96547e242732518ffe..b6e0f95bef3645659bf782adae8885c32670dde7 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -49,6 +49,7 @@
#include <linux/slab.h>
#include <linux/tcp.h>
#include <linux/udp.h>
+#include <linux/sctp.h>
#include <linux/netdevice.h>
#ifdef CONFIG_NET_CLS_ACT
#include <net/pkt_sched.h>
@@ -4383,6 +4384,8 @@ unsigned int skb_gso_transport_seglen(const struct sk_buff *skb)
thlen += inner_tcp_hdrlen(skb);
} else if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) {
thlen = tcp_hdrlen(skb);
+ } else if (unlikely(shinfo->gso_type & SKB_GSO_SCTP)) {
+ thlen = sizeof(struct sctphdr);
}
/* UFO sets gso_size to the size of the fragmentation
* payload, i.e. the size of the L4 (UDP) header is already
diff --git a/net/sctp/Makefile b/net/sctp/Makefile
index 0fca5824ad0e93c905e2cbd59ff2ff7e2077ca7c..6c4f7496cec612b52e1e69664a209b4d58763be5 100644
--- a/net/sctp/Makefile
+++ b/net/sctp/Makefile
@@ -11,7 +11,8 @@ sctp-y := sm_statetable.o sm_statefuns.o sm_sideeffect.o \
transport.o chunk.o sm_make_chunk.o ulpevent.o \
inqueue.o outqueue.o ulpqueue.o \
tsnmap.o bind_addr.o socket.o primitive.o \
- output.o input.o debug.o ssnmap.o auth.o
+ output.o input.o debug.o ssnmap.o auth.o \
+ offload.o
sctp_probe-y := probe.o
diff --git a/net/sctp/input.c b/net/sctp/input.c
index 5cff2546c3dd6d3823b5a28bac1e72880cd57756..6f8e676d285ead987b0a1337beec3b29c34e0a8e 100644
--- a/net/sctp/input.c
+++ b/net/sctp/input.c
@@ -139,7 +139,9 @@ int sctp_rcv(struct sk_buff *skb)
skb->csum_valid = 0; /* Previous value not applicable */
if (skb_csum_unnecessary(skb))
__skb_decr_checksum_unnecessary(skb);
- else if (!sctp_checksum_disable && sctp_rcv_checksum(net, skb) < 0)
+ else if (!sctp_checksum_disable &&
+ !(skb_shinfo(skb)->gso_type & SKB_GSO_SCTP) &&
+ sctp_rcv_checksum(net, skb) < 0)
goto discard_it;
skb->csum_valid = 1;
@@ -1175,6 +1177,14 @@ static struct sctp_association *__sctp_rcv_lookup_harder(struct net *net,
{
sctp_chunkhdr_t *ch;
+ /* We do not allow GSO frames here as we need to linearize and
+ * then cannot guarantee frame boundaries. This shouldn't be an
+ * issue as packets hitting this are mostly INIT or INIT-ACK and
+ * those cannot be on GSO-style anyway.
+ */
+ if ((skb_shinfo(skb)->gso_type & SKB_GSO_SCTP) = SKB_GSO_SCTP)
+ return NULL;
+
if (skb_linearize(skb))
return NULL;
diff --git a/net/sctp/inqueue.c b/net/sctp/inqueue.c
index 5ba08ceda3ab6cf61eb64c58bffb9ccd589e8664..edabbbdfca541b830526a7a52aee18c20680c19c 100644
--- a/net/sctp/inqueue.c
+++ b/net/sctp/inqueue.c
@@ -138,6 +138,17 @@ struct sctp_chunk *sctp_inq_pop(struct sctp_inq *queue)
if (chunk->singleton ||
chunk->end_of_packet ||
chunk->pdiscard) {
+ if (chunk->head_skb = chunk->skb) {
+ chunk->skb = skb_shinfo(chunk->skb)->frag_list;
+ goto new_skb;
+ }
+ if (chunk->skb->next) {
+ chunk->skb = chunk->skb->next;
+ goto new_skb;
+ }
+
+ if (chunk->head_skb)
+ chunk->skb = chunk->head_skb;
sctp_chunk_free(chunk);
chunk = queue->in_progress = NULL;
} else {
@@ -155,15 +166,15 @@ struct sctp_chunk *sctp_inq_pop(struct sctp_inq *queue)
next_chunk:
/* Is the queue empty? */
- if (list_empty(&queue->in_chunk_list))
+ entry = sctp_list_dequeue(&queue->in_chunk_list);
+ if (!entry)
return NULL;
- entry = queue->in_chunk_list.next;
chunk = list_entry(entry, struct sctp_chunk, list);
- list_del_init(entry);
/* Linearize if it's not GSO */
- if (skb_is_nonlinear(chunk->skb)) {
+ if ((skb_shinfo(chunk->skb)->gso_type & SKB_GSO_SCTP) != SKB_GSO_SCTP &&
+ skb_is_nonlinear(chunk->skb)) {
if (skb_linearize(chunk->skb)) {
__SCTP_INC_STATS(dev_net(chunk->skb->dev), SCTP_MIB_IN_PKT_DISCARDS);
sctp_chunk_free(chunk);
@@ -174,15 +185,39 @@ next_chunk:
chunk->sctp_hdr = sctp_hdr(chunk->skb);
}
+ if ((skb_shinfo(chunk->skb)->gso_type & SKB_GSO_SCTP) = SKB_GSO_SCTP) {
+ /* GSO-marked skbs but without frags, handle
+ * them normally
+ */
+ if (skb_shinfo(chunk->skb)->frag_list)
+ chunk->head_skb = chunk->skb;
+
+ /* skbs with "cover letter" */
+ if (chunk->head_skb && chunk->skb->data_len = chunk->skb->len)
+ chunk->skb = skb_shinfo(chunk->skb)->frag_list;
+
+ if (WARN_ON(!chunk->skb)) {
+ __SCTP_INC_STATS(dev_net(chunk->skb->dev), SCTP_MIB_IN_PKT_DISCARDS);
+ sctp_chunk_free(chunk);
+ goto next_chunk;
+ }
+ }
+
+ if (chunk->asoc)
+ sock_rps_save_rxhash(chunk->asoc->base.sk, chunk->skb);
+
queue->in_progress = chunk;
+new_skb:
/* This is the first chunk in the packet. */
- chunk->singleton = 1;
ch = (sctp_chunkhdr_t *) chunk->skb->data;
+ chunk->singleton = 1;
chunk->data_accepted = 0;
-
- if (chunk->asoc)
- sock_rps_save_rxhash(chunk->asoc->base.sk, chunk->skb);
+ chunk->pdiscard = 0;
+ chunk->auth = 0;
+ chunk->has_asconf = 0;
+ chunk->end_of_packet = 0;
+ chunk->ecn_ce_done = 0;
}
chunk->chunk_hdr = ch;
diff --git a/net/sctp/offload.c b/net/sctp/offload.c
new file mode 100644
index 0000000000000000000000000000000000000000..a37887b373a75524a54a1443f7df2d45ecf6cef7
--- /dev/null
+++ b/net/sctp/offload.c
@@ -0,0 +1,98 @@
+/*
+ * sctp_offload - GRO/GSO Offloading for SCTP
+ *
+ * Copyright (C) 2015, Marcelo Ricardo Leitner <marcelo.leitner@gmail.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 of the License, 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.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/kprobes.h>
+#include <linux/socket.h>
+#include <linux/sctp.h>
+#include <linux/proc_fs.h>
+#include <linux/vmalloc.h>
+#include <linux/module.h>
+#include <linux/kfifo.h>
+#include <linux/time.h>
+#include <net/net_namespace.h>
+
+#include <linux/skbuff.h>
+#include <net/sctp/sctp.h>
+#include <net/sctp/checksum.h>
+#include <net/protocol.h>
+
+static __le32 sctp_gso_make_checksum(struct sk_buff *skb)
+{
+ skb->ip_summed = CHECKSUM_NONE;
+ return sctp_compute_cksum(skb, skb_transport_offset(skb));
+}
+
+static struct sk_buff *sctp_gso_segment(struct sk_buff *skb,
+ netdev_features_t features)
+{
+ struct sk_buff *segs = ERR_PTR(-EINVAL);
+ struct sctphdr *sh;
+
+ sh = sctp_hdr(skb);
+ if (!pskb_may_pull(skb, sizeof(*sh)))
+ goto out;
+
+ __skb_pull(skb, sizeof(*sh));
+
+ if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) {
+ /* Packet is from an untrusted source, reset gso_segs. */
+ struct skb_shared_info *pinfo = skb_shinfo(skb);
+ struct sk_buff *frag_iter;
+
+ pinfo->gso_segs = 0;
+ if (skb->len != skb->data_len) {
+ /* Means we have chunks in here too */
+ pinfo->gso_segs++;
+ }
+
+ skb_walk_frags(skb, frag_iter)
+ pinfo->gso_segs++;
+
+ segs = NULL;
+ goto out;
+ }
+
+ segs = skb_segment(skb, features | NETIF_F_HW_CSUM);
+ if (IS_ERR(segs))
+ goto out;
+
+ /* All that is left is update SCTP CRC if necessary */
+ if (!(features & NETIF_F_SCTP_CRC)) {
+ for (skb = segs; skb; skb = skb->next) {
+ if (skb->ip_summed = CHECKSUM_PARTIAL) {
+ sh = sctp_hdr(skb);
+ sh->checksum = sctp_gso_make_checksum(skb);
+ }
+ }
+ }
+
+out:
+ return segs;
+}
+
+static const struct net_offload sctp_offload = {
+ .callbacks = {
+ .gso_segment = sctp_gso_segment,
+ },
+};
+
+int __init sctp_offload_init(void)
+{
+ return inet_add_offload(&sctp_offload, IPPROTO_SCTP);
+}
diff --git a/net/sctp/output.c b/net/sctp/output.c
index 9844fe573029b9e262743440980f15277ddaf5a1..60499a69179d255c47da1fa19b73147917a050bf 100644
--- a/net/sctp/output.c
+++ b/net/sctp/output.c
@@ -84,18 +84,42 @@ static void sctp_packet_reset(struct sctp_packet *packet)
struct sctp_packet *sctp_packet_config(struct sctp_packet *packet,
__u32 vtag, int ecn_capable)
{
- struct sctp_chunk *chunk = NULL;
+ struct sctp_transport *tp = packet->transport;
+ struct sctp_association *asoc = tp->asoc;
pr_debug("%s: packet:%p vtag:0x%x\n", __func__, packet, vtag);
packet->vtag = vtag;
+ if (asoc && tp->dst) {
+ struct sock *sk = asoc->base.sk;
+
+ rcu_read_lock();
+ if (__sk_dst_get(sk) != tp->dst) {
+ dst_hold(tp->dst);
+ sk_setup_caps(sk, tp->dst);
+ }
+
+ if (sk_can_gso(sk)) {
+ struct net_device *dev = tp->dst->dev;
+
+ packet->max_size = dev->gso_max_size;
+ } else {
+ packet->max_size = asoc->pathmtu;
+ }
+ rcu_read_unlock();
+
+ } else {
+ packet->max_size = tp->pathmtu;
+ }
+
if (ecn_capable && sctp_packet_empty(packet)) {
- chunk = sctp_get_ecne_prepend(packet->transport->asoc);
+ struct sctp_chunk *chunk;
/* If there a is a prepend chunk stick it on the list before
* any other chunks get appended.
*/
+ chunk = sctp_get_ecne_prepend(asoc);
if (chunk)
sctp_packet_append_chunk(packet, chunk);
}
@@ -381,12 +405,15 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
struct sctp_transport *tp = packet->transport;
struct sctp_association *asoc = tp->asoc;
struct sctphdr *sh;
- struct sk_buff *nskb;
+ struct sk_buff *nskb = NULL, *head = NULL;
struct sctp_chunk *chunk, *tmp;
struct sock *sk;
int err = 0;
int padding; /* How much padding do we need? */
+ int pkt_size;
__u8 has_data = 0;
+ int gso = 0;
+ int pktcount = 0;
struct dst_entry *dst;
unsigned char *auth = NULL; /* pointer to auth in skb data */
@@ -400,18 +427,37 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
chunk = list_entry(packet->chunk_list.next, struct sctp_chunk, list);
sk = chunk->skb->sk;
- /* Allocate the new skb. */
- nskb = alloc_skb(packet->size + MAX_HEADER, gfp);
- if (!nskb)
+ /* Allocate the head skb, or main one if not in GSO */
+ if (packet->size > tp->pathmtu && !packet->ipfragok) {
+ if (sk_can_gso(sk)) {
+ gso = 1;
+ pkt_size = packet->overhead;
+ } else {
+ /* If this happens, we trash this packet and try
+ * to build a new one, hopefully correct this
+ * time. Application may notice this error.
+ */
+ pr_err_once("Trying to GSO but underlying device doesn't support it.");
+ goto nomem;
+ }
+ } else {
+ pkt_size = packet->size;
+ }
+ head = alloc_skb(pkt_size + MAX_HEADER, gfp);
+ if (!head)
goto nomem;
+ if (gso) {
+ NAPI_GRO_CB(head)->last = head;
+ skb_shinfo(head)->gso_type = sk->sk_gso_type;
+ }
/* Make sure the outbound skb has enough header room reserved. */
- skb_reserve(nskb, packet->overhead + MAX_HEADER);
+ skb_reserve(head, packet->overhead + MAX_HEADER);
/* Set the owning socket so that we know where to get the
* destination IP address.
*/
- sctp_packet_set_owner_w(nskb, sk);
+ sctp_packet_set_owner_w(head, sk);
if (!sctp_transport_dst_check(tp)) {
sctp_transport_route(tp, NULL, sctp_sk(sk));
@@ -422,11 +468,11 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
dst = dst_clone(tp->dst);
if (!dst)
goto no_route;
- skb_dst_set(nskb, dst);
+ skb_dst_set(head, dst);
/* Build the SCTP header. */
- sh = (struct sctphdr *)skb_push(nskb, sizeof(struct sctphdr));
- skb_reset_transport_header(nskb);
+ sh = (struct sctphdr *)skb_push(head, sizeof(struct sctphdr));
+ skb_reset_transport_header(head);
sh->source = htons(packet->source_port);
sh->dest = htons(packet->destination_port);
@@ -441,90 +487,133 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
sh->vtag = htonl(packet->vtag);
sh->checksum = 0;
- /**
- * 6.10 Bundling
- *
- * An endpoint bundles chunks by simply including multiple
- * chunks in one outbound SCTP packet. ...
- */
-
- /**
- * 3.2 Chunk Field Descriptions
- *
- * The total length of a chunk (including Type, Length and
- * Value fields) MUST be a multiple of 4 bytes. If the length
- * of the chunk is not a multiple of 4 bytes, the sender MUST
- * pad the chunk with all zero bytes and this padding is not
- * included in the chunk length field. The sender should
- * never pad with more than 3 bytes.
- *
- * [This whole comment explains WORD_ROUND() below.]
- */
-
pr_debug("***sctp_transmit_packet***\n");
- list_for_each_entry_safe(chunk, tmp, &packet->chunk_list, list) {
- list_del_init(&chunk->list);
- if (sctp_chunk_is_data(chunk)) {
- /* 6.3.1 C4) When data is in flight and when allowed
- * by rule C5, a new RTT measurement MUST be made each
- * round trip. Furthermore, new RTT measurements
- * SHOULD be made no more than once per round-trip
- * for a given destination transport address.
- */
+ do {
+ /* Set up convenience variables... */
+ chunk = list_entry(packet->chunk_list.next, struct sctp_chunk, list);
+ pktcount++;
- if (!chunk->resent && !tp->rto_pending) {
- chunk->rtt_in_progress = 1;
- tp->rto_pending = 1;
+ /* Calculate packet size, so it fits in PMTU. Leave
+ * other chunks for the next packets.
+ */
+ if (gso) {
+ pkt_size = packet->overhead;
+ list_for_each_entry(chunk, &packet->chunk_list, list) {
+ int padded = WORD_ROUND(chunk->skb->len);
+
+ if (pkt_size + padded > tp->pathmtu)
+ break;
+ pkt_size += padded;
}
- has_data = 1;
- }
+ /* Allocate a new skb. */
+ nskb = alloc_skb(pkt_size + MAX_HEADER, gfp);
+ if (!nskb)
+ goto nomem;
- padding = WORD_ROUND(chunk->skb->len) - chunk->skb->len;
- if (padding)
- memset(skb_put(chunk->skb, padding), 0, padding);
+ /* Make sure the outbound skb has enough header
+ * room reserved.
+ */
+ skb_reserve(nskb, packet->overhead + MAX_HEADER);
+ } else {
+ nskb = head;
+ }
- /* if this is the auth chunk that we are adding,
- * store pointer where it will be added and put
- * the auth into the packet.
+ /**
+ * 3.2 Chunk Field Descriptions
+ *
+ * The total length of a chunk (including Type, Length and
+ * Value fields) MUST be a multiple of 4 bytes. If the length
+ * of the chunk is not a multiple of 4 bytes, the sender MUST
+ * pad the chunk with all zero bytes and this padding is not
+ * included in the chunk length field. The sender should
+ * never pad with more than 3 bytes.
+ *
+ * [This whole comment explains WORD_ROUND() below.]
*/
- if (chunk = packet->auth)
- auth = skb_tail_pointer(nskb);
- memcpy(skb_put(nskb, chunk->skb->len),
+ pkt_size -= packet->overhead;
+ list_for_each_entry_safe(chunk, tmp, &packet->chunk_list, list) {
+ list_del_init(&chunk->list);
+ if (sctp_chunk_is_data(chunk)) {
+ /* 6.3.1 C4) When data is in flight and when allowed
+ * by rule C5, a new RTT measurement MUST be made each
+ * round trip. Furthermore, new RTT measurements
+ * SHOULD be made no more than once per round-trip
+ * for a given destination transport address.
+ */
+
+ if (!chunk->resent && !tp->rto_pending) {
+ chunk->rtt_in_progress = 1;
+ tp->rto_pending = 1;
+ }
+
+ has_data = 1;
+ }
+
+ padding = WORD_ROUND(chunk->skb->len) - chunk->skb->len;
+ if (padding)
+ memset(skb_put(chunk->skb, padding), 0, padding);
+
+ /* if this is the auth chunk that we are adding,
+ * store pointer where it will be added and put
+ * the auth into the packet.
+ */
+ if (chunk = packet->auth)
+ auth = skb_tail_pointer(nskb);
+
+ memcpy(skb_put(nskb, chunk->skb->len),
chunk->skb->data, chunk->skb->len);
- pr_debug("*** Chunk:%p[%s] %s 0x%x, length:%d, chunk->skb->len:%d, "
- "rtt_in_progress:%d\n", chunk,
- sctp_cname(SCTP_ST_CHUNK(chunk->chunk_hdr->type)),
- chunk->has_tsn ? "TSN" : "No TSN",
- chunk->has_tsn ? ntohl(chunk->subh.data_hdr->tsn) : 0,
- ntohs(chunk->chunk_hdr->length), chunk->skb->len,
- chunk->rtt_in_progress);
-
- /*
- * If this is a control chunk, this is our last
- * reference. Free data chunks after they've been
- * acknowledged or have failed.
- */
- if (!sctp_chunk_is_data(chunk))
- sctp_chunk_free(chunk);
- }
+ pr_debug("*** Chunk:%p[%s] %s 0x%x, length:%d, chunk->skb->len:%d, rtt_in_progress:%d\n",
+ chunk,
+ sctp_cname(SCTP_ST_CHUNK(chunk->chunk_hdr->type)),
+ chunk->has_tsn ? "TSN" : "No TSN",
+ chunk->has_tsn ? ntohl(chunk->subh.data_hdr->tsn) : 0,
+ ntohs(chunk->chunk_hdr->length), chunk->skb->len,
+ chunk->rtt_in_progress);
+
+ /* If this is a control chunk, this is our last
+ * reference. Free data chunks after they've been
+ * acknowledged or have failed.
+ * Re-queue auth chunks if needed.
+ */
+ pkt_size -= WORD_ROUND(chunk->skb->len);
- /* SCTP-AUTH, Section 6.2
- * The sender MUST calculate the MAC as described in RFC2104 [2]
- * using the hash function H as described by the MAC Identifier and
- * the shared association key K based on the endpoint pair shared key
- * described by the shared key identifier. The 'data' used for the
- * computation of the AUTH-chunk is given by the AUTH chunk with its
- * HMAC field set to zero (as shown in Figure 6) followed by all
- * chunks that are placed after the AUTH chunk in the SCTP packet.
- */
- if (auth)
- sctp_auth_calculate_hmac(asoc, nskb,
- (struct sctp_auth_chunk *)auth,
- gfp);
+ if (chunk = packet->auth && !list_empty(&packet->chunk_list))
+ list_add(&chunk->list, &packet->chunk_list);
+ else if (!sctp_chunk_is_data(chunk))
+ sctp_chunk_free(chunk);
+
+ if (!pkt_size)
+ break;
+ }
+
+ /* SCTP-AUTH, Section 6.2
+ * The sender MUST calculate the MAC as described in RFC2104 [2]
+ * using the hash function H as described by the MAC Identifier and
+ * the shared association key K based on the endpoint pair shared key
+ * described by the shared key identifier. The 'data' used for the
+ * computation of the AUTH-chunk is given by the AUTH chunk with its
+ * HMAC field set to zero (as shown in Figure 6) followed by all
+ * chunks that are placed after the AUTH chunk in the SCTP packet.
+ */
+ if (auth)
+ sctp_auth_calculate_hmac(asoc, nskb,
+ (struct sctp_auth_chunk *)auth,
+ gfp);
+
+ if (!gso)
+ break;
+
+ if (skb_gro_receive(&head, nskb))
+ goto nomem;
+ nskb = NULL;
+ if (WARN_ON_ONCE(skb_shinfo(head)->gso_segs >+ sk->sk_gso_max_segs))
+ goto nomem;
+ } while (!list_empty(&packet->chunk_list));
/* 2) Calculate the Adler-32 checksum of the whole packet,
* including the SCTP common header and all the
@@ -532,16 +621,18 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
*
* Note: Adler-32 is no longer applicable, as has been replaced
* by CRC32-C as described in <draft-ietf-tsvwg-sctpcsum-02.txt>.
+ *
+ * If it's a GSO packet, it's postponed to sctp_skb_segment.
*/
- if (!sctp_checksum_disable) {
- if (!(dst->dev->features & NETIF_F_SCTP_CRC) ||
- (dst_xfrm(dst) != NULL) || packet->ipfragok) {
- sh->checksum = sctp_compute_cksum(nskb, 0);
+ if (!sctp_checksum_disable || gso) {
+ if (!gso && (!(dst->dev->features & NETIF_F_SCTP_CRC) ||
+ dst_xfrm(dst) || packet->ipfragok)) {
+ sh->checksum = sctp_compute_cksum(head, 0);
} else {
/* no need to seed pseudo checksum for SCTP */
- nskb->ip_summed = CHECKSUM_PARTIAL;
- nskb->csum_start = skb_transport_header(nskb) - nskb->head;
- nskb->csum_offset = offsetof(struct sctphdr, checksum);
+ head->ip_summed = CHECKSUM_PARTIAL;
+ head->csum_start = skb_transport_header(head) - head->head;
+ head->csum_offset = offsetof(struct sctphdr, checksum);
}
}
@@ -557,7 +648,7 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
* Note: The works for IPv6 layer checks this bit too later
* in transmission. See IP6_ECN_flow_xmit().
*/
- tp->af_specific->ecn_capable(nskb->sk);
+ tp->af_specific->ecn_capable(sk);
/* Set up the IP options. */
/* BUG: not implemented
@@ -566,7 +657,7 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
/* Dump that on IP! */
if (asoc) {
- asoc->stats.opackets++;
+ asoc->stats.opackets += pktcount;
if (asoc->peer.last_sent_to != tp)
/* Considering the multiple CPU scenario, this is a
* "correcter" place for last_sent_to. --xguo
@@ -589,16 +680,36 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp)
}
}
- pr_debug("***sctp_transmit_packet*** skb->len:%d\n", nskb->len);
+ pr_debug("***sctp_transmit_packet*** skb->len:%d\n", head->len);
+
+ if (gso) {
+ /* Cleanup our debris for IP stacks */
+ memset(head->cb, 0, max(sizeof(struct inet_skb_parm),
+ sizeof(struct inet6_skb_parm)));
- nskb->ignore_df = packet->ipfragok;
- tp->af_specific->sctp_xmit(nskb, tp);
+ skb_shinfo(head)->gso_segs = pktcount;
+ skb_shinfo(head)->gso_size = GSO_BY_FRAGS;
+
+ /* We have to refresh this in case we are xmiting to
+ * more than one transport at a time
+ */
+ rcu_read_lock();
+ if (__sk_dst_get(sk) != tp->dst) {
+ dst_hold(tp->dst);
+ sk_setup_caps(sk, tp->dst);
+ }
+ rcu_read_unlock();
+ }
+ head->ignore_df = packet->ipfragok;
+ tp->af_specific->sctp_xmit(head, tp);
out:
sctp_packet_reset(packet);
return err;
no_route:
- kfree_skb(nskb);
+ kfree_skb(head);
+ if (nskb != head)
+ kfree_skb(nskb);
if (asoc)
IP_INC_STATS(sock_net(asoc->base.sk), IPSTATS_MIB_OUTNOROUTES);
@@ -751,39 +862,63 @@ static sctp_xmit_t sctp_packet_will_fit(struct sctp_packet *packet,
struct sctp_chunk *chunk,
u16 chunk_len)
{
- size_t psize;
- size_t pmtu;
- int too_big;
+ size_t psize, pmtu;
sctp_xmit_t retval = SCTP_XMIT_OK;
psize = packet->size;
- pmtu = ((packet->transport->asoc) ?
- (packet->transport->asoc->pathmtu) :
- (packet->transport->pathmtu));
-
- too_big = (psize + chunk_len > pmtu);
+ if (packet->transport->asoc)
+ pmtu = packet->transport->asoc->pathmtu;
+ else
+ pmtu = packet->transport->pathmtu;
/* Decide if we need to fragment or resubmit later. */
- if (too_big) {
- /* It's OK to fragmet at IP level if any one of the following
+ if (psize + chunk_len > pmtu) {
+ /* It's OK to fragment at IP level if any one of the following
* is true:
- * 1. The packet is empty (meaning this chunk is greater
- * the MTU)
- * 2. The chunk we are adding is a control chunk
- * 3. The packet doesn't have any data in it yet and data
- * requires authentication.
+ * 1. The packet is empty (meaning this chunk is greater
+ * the MTU)
+ * 2. The packet doesn't have any data in it yet and data
+ * requires authentication.
*/
- if (sctp_packet_empty(packet) || !sctp_chunk_is_data(chunk) ||
+ if (sctp_packet_empty(packet) ||
(!packet->has_data && chunk->auth)) {
/* We no longer do re-fragmentation.
* Just fragment at the IP layer, if we
* actually hit this condition
*/
packet->ipfragok = 1;
- } else {
- retval = SCTP_XMIT_PMTU_FULL;
+ goto out;
}
+
+ /* It is also okay to fragment if the chunk we are
+ * adding is a control chunk, but only if current packet
+ * is not a GSO one otherwise it causes fragmentation of
+ * a large frame. So in this case we allow the
+ * fragmentation by forcing it to be in a new packet.
+ */
+ if (!sctp_chunk_is_data(chunk) && packet->has_data)
+ retval = SCTP_XMIT_PMTU_FULL;
+
+ if (psize + chunk_len > packet->max_size)
+ /* Hit GSO/PMTU limit, gotta flush */
+ retval = SCTP_XMIT_PMTU_FULL;
+
+ if (!packet->transport->burst_limited &&
+ psize + chunk_len > (packet->transport->cwnd >> 1))
+ /* Do not allow a single GSO packet to use more
+ * than half of cwnd.
+ */
+ retval = SCTP_XMIT_PMTU_FULL;
+
+ if (packet->transport->burst_limited &&
+ psize + chunk_len > (packet->transport->burst_limited >> 1))
+ /* Do not allow a single GSO packet to use more
+ * than half of original cwnd.
+ */
+ retval = SCTP_XMIT_PMTU_FULL;
+ /* Otherwise it will fit in the GSO packet */
}
+out:
return retval;
}
diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c
index d3d50daa248b06d7a4306d903b2dad89e9d2acbd..40022ee885d7e8d9fbce3c7d9df43f57f0bcfa0e 100644
--- a/net/sctp/protocol.c
+++ b/net/sctp/protocol.c
@@ -1516,6 +1516,9 @@ static __init int sctp_init(void)
if (status)
goto err_v6_add_protocol;
+ if (sctp_offload_init() < 0)
+ pr_crit("%s: Cannot add SCTP protocol offload\n", __func__);
+
out:
return status;
err_v6_add_protocol:
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 67154b848aa9bae93ce2bc6941e7974acb678142..712fb2339baa24fc0a2e354e8aaea72de8acdc81 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -4003,6 +4003,8 @@ static int sctp_init_sock(struct sock *sk)
return -ESOCKTNOSUPPORT;
}
+ sk->sk_gso_type = SKB_GSO_SCTP;
+
/* Initialize default send parameters. These parameters can be
* modified with the SCTP_DEFAULT_SEND_PARAM socket option.
*/
--
2.5.5
^ permalink raw reply related [flat|nested] 9+ messages in thread