[RFC,v4,07/17] vsock: read from socket's error queue

Message ID 20230603204939.1598818-8-AVKrasnov@sberdevices.ru
State New
Headers
Series vsock: MSG_ZEROCOPY flag support |

Commit Message

Arseniy Krasnov June 3, 2023, 8:49 p.m. UTC
  This adds handling of MSG_ERRQUEUE input flag in receive call. This flag
is used to read socket's error queue instead of data queue. Possible
scenario of error queue usage is receiving completions for transmission
with MSG_ZEROCOPY flag.

Signed-off-by: Arseniy Krasnov <AVKrasnov@sberdevices.ru>
---
 include/linux/socket.h   | 1 +
 net/vmw_vsock/af_vsock.c | 5 +++++
 2 files changed, 6 insertions(+)
  

Comments

Stefano Garzarella June 26, 2023, 4:08 p.m. UTC | #1
On Sat, Jun 03, 2023 at 11:49:29PM +0300, Arseniy Krasnov wrote:
>This adds handling of MSG_ERRQUEUE input flag in receive call. This flag
>is used to read socket's error queue instead of data queue. Possible
>scenario of error queue usage is receiving completions for transmission
>with MSG_ZEROCOPY flag.
>
>Signed-off-by: Arseniy Krasnov <AVKrasnov@sberdevices.ru>
>---
> include/linux/socket.h   | 1 +
> net/vmw_vsock/af_vsock.c | 5 +++++
> 2 files changed, 6 insertions(+)
>
>diff --git a/include/linux/socket.h b/include/linux/socket.h
>index bd1cc3238851..d79efd026880 100644
>--- a/include/linux/socket.h
>+++ b/include/linux/socket.h
>@@ -382,6 +382,7 @@ struct ucred {
> #define SOL_MPTCP	284
> #define SOL_MCTP	285
> #define SOL_SMC		286
>+#define SOL_VSOCK	287

Maybe this change should go in another patch where we describe that
we need to support setsockopt()

>
> /* IPX options */
> #define IPX_TYPE	1
>diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
>index 45fd20c4ed50..07803d9fbf6d 100644
>--- a/net/vmw_vsock/af_vsock.c
>+++ b/net/vmw_vsock/af_vsock.c
>@@ -110,6 +110,7 @@
> #include <linux/workqueue.h>
> #include <net/sock.h>
> #include <net/af_vsock.h>
>+#include <linux/errqueue.h>
>
> static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr);
> static void vsock_sk_destruct(struct sock *sk);
>@@ -2135,6 +2136,10 @@ vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
> 	int err;
>
> 	sk = sock->sk;
>+
>+	if (unlikely(flags & MSG_ERRQUEUE))
>+		return sock_recv_errqueue(sk, msg, len, SOL_VSOCK, 0);
>+
> 	vsk = vsock_sk(sk);
> 	err = 0;
>
>-- 
>2.25.1
>
  
Arseniy Krasnov June 27, 2023, 4:49 a.m. UTC | #2
On 26.06.2023 19:08, Stefano Garzarella wrote:
> On Sat, Jun 03, 2023 at 11:49:29PM +0300, Arseniy Krasnov wrote:
>> This adds handling of MSG_ERRQUEUE input flag in receive call. This flag
>> is used to read socket's error queue instead of data queue. Possible
>> scenario of error queue usage is receiving completions for transmission
>> with MSG_ZEROCOPY flag.
>>
>> Signed-off-by: Arseniy Krasnov <AVKrasnov@sberdevices.ru>
>> ---
>> include/linux/socket.h   | 1 +
>> net/vmw_vsock/af_vsock.c | 5 +++++
>> 2 files changed, 6 insertions(+)
>>
>> diff --git a/include/linux/socket.h b/include/linux/socket.h
>> index bd1cc3238851..d79efd026880 100644
>> --- a/include/linux/socket.h
>> +++ b/include/linux/socket.h
>> @@ -382,6 +382,7 @@ struct ucred {
>> #define SOL_MPTCP    284
>> #define SOL_MCTP    285
>> #define SOL_SMC        286
>> +#define SOL_VSOCK    287
> 
> Maybe this change should go in another patch where we describe that
> we need to support setsockopt()

Ok, You mean patch which handles SO_ZEROCOPY option in af_vsock.c as Bobby suggested? No
problem, but in this case there will be no user for this define there - this option
(SO_ZEROCOPY) uses SOL_SOCKET level, not SOL_VSOCK.

Thanks, Arseniy

> 
>>
>> /* IPX options */
>> #define IPX_TYPE    1
>> diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
>> index 45fd20c4ed50..07803d9fbf6d 100644
>> --- a/net/vmw_vsock/af_vsock.c
>> +++ b/net/vmw_vsock/af_vsock.c
>> @@ -110,6 +110,7 @@
>> #include <linux/workqueue.h>
>> #include <net/sock.h>
>> #include <net/af_vsock.h>
>> +#include <linux/errqueue.h>
>>
>> static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr);
>> static void vsock_sk_destruct(struct sock *sk);
>> @@ -2135,6 +2136,10 @@ vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
>>     int err;
>>
>>     sk = sock->sk;
>> +
>> +    if (unlikely(flags & MSG_ERRQUEUE))
>> +        return sock_recv_errqueue(sk, msg, len, SOL_VSOCK, 0);
>> +
>>     vsk = vsock_sk(sk);
>>     err = 0;
>>
>> -- 
>> 2.25.1
>>
>
  
Stefano Garzarella June 27, 2023, 7:58 a.m. UTC | #3
On Tue, Jun 27, 2023 at 07:49:00AM +0300, Arseniy Krasnov wrote:
>
>
>On 26.06.2023 19:08, Stefano Garzarella wrote:
>> On Sat, Jun 03, 2023 at 11:49:29PM +0300, Arseniy Krasnov wrote:
>>> This adds handling of MSG_ERRQUEUE input flag in receive call. This flag
>>> is used to read socket's error queue instead of data queue. Possible
>>> scenario of error queue usage is receiving completions for transmission
>>> with MSG_ZEROCOPY flag.
>>>
>>> Signed-off-by: Arseniy Krasnov <AVKrasnov@sberdevices.ru>
>>> ---
>>> include/linux/socket.h   | 1 +
>>> net/vmw_vsock/af_vsock.c | 5 +++++
>>> 2 files changed, 6 insertions(+)
>>>
>>> diff --git a/include/linux/socket.h b/include/linux/socket.h
>>> index bd1cc3238851..d79efd026880 100644
>>> --- a/include/linux/socket.h
>>> +++ b/include/linux/socket.h
>>> @@ -382,6 +382,7 @@ struct ucred {
>>> #define SOL_MPTCP    284
>>> #define SOL_MCTP    285
>>> #define SOL_SMC        286
>>> +#define SOL_VSOCK    287
>>
>> Maybe this change should go in another patch where we describe that
>> we need to support setsockopt()
>
>Ok, You mean patch which handles SO_ZEROCOPY option in af_vsock.c as Bobby suggested? No
>problem, but in this case there will be no user for this define there - this option
>(SO_ZEROCOPY) uses SOL_SOCKET level, not SOL_VSOCK.

Got it, so it is fine to leave it here.

Just mention that we are defining SOL_VSOCK in the commit description.

Thanks,
Stefano
  

Patch

diff --git a/include/linux/socket.h b/include/linux/socket.h
index bd1cc3238851..d79efd026880 100644
--- a/include/linux/socket.h
+++ b/include/linux/socket.h
@@ -382,6 +382,7 @@  struct ucred {
 #define SOL_MPTCP	284
 #define SOL_MCTP	285
 #define SOL_SMC		286
+#define SOL_VSOCK	287
 
 /* IPX options */
 #define IPX_TYPE	1
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 45fd20c4ed50..07803d9fbf6d 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -110,6 +110,7 @@ 
 #include <linux/workqueue.h>
 #include <net/sock.h>
 #include <net/af_vsock.h>
+#include <linux/errqueue.h>
 
 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr);
 static void vsock_sk_destruct(struct sock *sk);
@@ -2135,6 +2136,10 @@  vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
 	int err;
 
 	sk = sock->sk;
+
+	if (unlikely(flags & MSG_ERRQUEUE))
+		return sock_recv_errqueue(sk, msg, len, SOL_VSOCK, 0);
+
 	vsk = vsock_sk(sk);
 	err = 0;