Although TPACKET_V3 Rx has some benefits over TPACKET_V2 Rx,
*_v3 does not currently have Tx support. As a result an application
that wants the best perf for Tx and Rx (e.g. to handle
request/response transacations) ends up needing 2 sockets,
one with *_v2 for Tx and another with *_v3 for Rx.
This patch enables TPACKET_V2 compatible Tx features in TPACKET_V3
so that _v3 supports at least as many features as _v2.
Signed-off-by: Sowmini Varadhan <sowmini.varad...@oracle.com>
---
Documentation/networking/packet_mmap.txt | 6 ++++--
net/packet/af_packet.c | 23 +++++++++++++++--------
2 files changed, 19 insertions(+), 10 deletions(-)
diff --git a/Documentation/networking/packet_mmap.txt
b/Documentation/networking/packet_mmap.txt
index daa015a..6425062 100644
--- a/Documentation/networking/packet_mmap.txt
+++ b/Documentation/networking/packet_mmap.txt
@@ -565,7 +565,7 @@ where 'tpacket_version' can be TPACKET_V1 (default),
TPACKET_V2, TPACKET_V3.
(void *)hdr + TPACKET_ALIGN(sizeof(struct tpacket_hdr))
TPACKET_V2 --> TPACKET_V3:
- - Flexible buffer implementation:
+ - Flexible buffer implementation for RX_RING:
1. Blocks can be configured with non-static frame-size
2. Read/poll is at a block-level (as opposed to packet-level)
3. Added poll timeout to avoid indefinite user-space wait
@@ -574,7 +574,9 @@ where 'tpacket_version' can be TPACKET_V1 (default),
TPACKET_V2, TPACKET_V3.
4.1 block::timeout
4.2 tpkt_hdr::sk_rxhash
- RX Hash data available in user space
- - Currently only RX_RING available
+ - TX_RING semantics are conceptually similar to TPACKET_V2;
+ use tpacket3_hdr instead of tpacket2_hdr, and TPACKET3_HDRLEN
+ instead of TPACKET2_HDRLEN.
-------------------------------------------------------------------------------
+ AF_PACKET fanout mode
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 89f2e8c..57692af 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -409,6 +409,9 @@ static void __packet_set_status(struct packet_sock *po,
void *frame, int status)
flush_dcache_page(pgv_to_page(&h.h2->tp_status));
break;
case TPACKET_V3:
+ h.h3->tp_status = status;
+ flush_dcache_page(pgv_to_page(&h.h3->tp_status));
+ break;
default:
WARN(1, "TPACKET version not supported.\n");
BUG();
@@ -432,6 +435,8 @@ static int __packet_get_status(struct packet_sock *po, void
*frame)
flush_dcache_page(pgv_to_page(&h.h2->tp_status));
return h.h2->tp_status;
case TPACKET_V3:
+ flush_dcache_page(pgv_to_page(&h.h3->tp_status));
+ return h.h3->tp_status;
default:
WARN(1, "TPACKET version not supported.\n");
BUG();
@@ -2500,6 +2505,9 @@ static int tpacket_parse_header(struct packet_sock *po,
void *frame,
ph.raw = frame;
switch (po->tp_version) {
+ case TPACKET_V3:
+ tp_len = ph.h3->tp_len;
+ break;
case TPACKET_V2:
tp_len = ph.h2->tp_len;
break;
@@ -2519,6 +2527,9 @@ static int tpacket_parse_header(struct packet_sock *po,
void *frame,
off_max = po->tx_ring.frame_size - tp_len;
if (po->sk.sk_type == SOCK_DGRAM) {
switch (po->tp_version) {
+ case TPACKET_V3:
+ off = ph.h3->tp_net;
+ break;
case TPACKET_V2:
off = ph.h2->tp_net;
break;
@@ -2528,6 +2539,9 @@ static int tpacket_parse_header(struct packet_sock *po,
void *frame,
}
} else {
switch (po->tp_version) {
+ case TPACKET_V3:
+ off = ph.h3->tp_mac;
+ break;
case TPACKET_V2:
off = ph.h2->tp_mac;
break;
@@ -4116,11 +4130,6 @@ static int packet_set_ring(struct sock *sk, union
tpacket_req_u *req_u,
struct tpacket_req *req = &req_u->req;
lock_sock(sk);
- /* Opening a Tx-ring is NOT supported in TPACKET_V3 */
- if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
- net_warn_ratelimited("Tx-ring is not supported.\n");
- goto out;
- }
rb = tx_ring ? &po->tx_ring : &po->rx_ring;
rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
@@ -4180,9 +4189,7 @@ static int packet_set_ring(struct sock *sk, union
tpacket_req_u *req_u,
goto out;
switch (po->tp_version) {
case TPACKET_V3:
- /* Transmit path is not supported. We checked
- * it above but just being paranoid
- */
+ /* Block transmit is not supported yet */
if (!tx_ring)
init_prb_bdqc(po, rb, pg_vec, req_u);
break;
--
1.7.1
