On 10/24/22 15:12, Stefan Metzmacher wrote:
Am 24.10.22 um 14:49 schrieb Stefan Metzmacher:
Am 22.10.22 um 18:07 schrieb Jens Axboe:
On 10/22/22 9:57 AM, Pavel Begunkov wrote:
On 10/21/22 17:14, Jakub Kicinski wrote:
On Fri, 21 Oct 2022 11:16:39 +0100 Pavel Begunkov wrote:
We need an efficient way in io_uring to check whether a socket supports
zerocopy with msghdr provided ubuf_info. Add a new flag into the struct
socket flags fields.
Cc: <stable@xxxxxxxxxxxxxxx> # 6.0
Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx>
---
? include/linux/net.h | 1 +
? net/ipv4/tcp.c????? | 1 +
? net/ipv4/udp.c????? | 1 +
? 3 files changed, 3 insertions(+)
diff --git a/include/linux/net.h b/include/linux/net.h
index 711c3593c3b8..18d942bbdf6e 100644
--- a/include/linux/net.h
+++ b/include/linux/net.h
@@ -41,6 +41,7 @@ struct net;
? #define SOCK_NOSPACE??????? 2
? #define SOCK_PASSCRED??????? 3
? #define SOCK_PASSSEC??????? 4
+#define SOCK_SUPPORT_ZC??????? 5
Acked-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Any idea on when this will make it to Linus? If within a week we can
probably delay:
After a chat with Jens, IIUC he can take it and send out to
Linus early. So, sounds like a good plan
Yes, and let's retain the name for now, can always be changed if we need
to make it more granular. I'll ship this off before -rc2.
I'm now always getting -EOPNOTSUPP from SENDMSG_ZC for tcp connections...
The problem is that inet_accept() doesn't set SOCK_SUPPORT_ZC...
Yeah, you're right, accept is not handled, not great. Thanks
for tracking it down. And I'll add a test for it
This hack below fixes it for me, but I'm sure there's a nicer way...
The natural way would be to overload inet_csk_accept for tcp,
but sk1->sk_prot->accept() is called with sk2->sk_socket == NULL,
because sock_graft() is called later...
I think it's acceptable for a fix. sk_is_tcp() sounds a bit better
assuming that sk_type/protocol are set there.
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 3dd02396517d..0f35f2a32756 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -736,6 +736,7 @@ EXPORT_SYMBOL(inet_stream_connect);
* Accept a pending connection. The TCP layer now gives BSD semantics.
*/
+#include <net/transp_v6.h>
int inet_accept(struct socket *sock, struct socket *newsock, int flags,
bool kern)
{
@@ -754,6 +755,8 @@ int inet_accept(struct socket *sock, struct socket *newsock, int flags,
(TCPF_ESTABLISHED | TCPF_SYN_RECV |
TCPF_CLOSE_WAIT | TCPF_CLOSE)));
+ if (sk2->sk_prot == &tcp_prot || sk2->sk_prot == &tcpv6_prot)
+ set_bit(SOCK_SUPPORT_ZC, &newsock->flags);
sock_graft(sk2, newsock);
newsock->state = SS_CONNECTED;
--
Pavel Begunkov
