diff mbox series

[net-next,v4,02/12] vsock: read from socket's error queue

Message ID 20231010191524.1694217-3-avkrasnov@salutedevices.com (mailing list archive)
State Accepted
Commit 49dbe25adac42d3e06f65d1420946bec65896222
Delegated to: Netdev Maintainers
Headers show
Series vsock/virtio: continue MSG_ZEROCOPY support | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next, async
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 6994 this patch: 6994
netdev/cc_maintainers warning 2 maintainers not CCed: dhowells@redhat.com keescook@chromium.org
netdev/build_clang success Errors and warnings before: 2962 this patch: 2962
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 12053 this patch: 12053
netdev/checkpatch warning WARNING: line length of 82 exceeds 80 columns
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Arseniy Krasnov Oct. 10, 2023, 7:15 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. This patch also adds new defines: 'SOL_VSOCK'
and 'VSOCK_RECVERR'.

Signed-off-by: Arseniy Krasnov <avkrasnov@salutedevices.com>
---
 Changelog:
 v1 -> v2:
  * Place new defines for userspace to the existing file 'vm_sockets.h'
    instead of creating new one.
 v2 -> v3:
  * Add comments to describe 'SOL_VSOCK' and 'VSOCK_RECVERR' in the file
    'vm_sockets.h'.
  * Reorder includes in 'af_vsock.c' in alphabetical order.
 v3 -> v4:
  * Update comments for 'SOL_VSOCK' and 'VSOCK_RECVERR' by adding more
    details.

 include/linux/socket.h          |  1 +
 include/uapi/linux/vm_sockets.h | 17 +++++++++++++++++
 net/vmw_vsock/af_vsock.c        |  6 ++++++
 3 files changed, 24 insertions(+)

Comments

Stefano Garzarella Oct. 11, 2023, 12:54 p.m. UTC | #1
On Tue, Oct 10, 2023 at 10:15:14PM +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. This patch also adds new defines: 'SOL_VSOCK'
>and 'VSOCK_RECVERR'.
>
>Signed-off-by: Arseniy Krasnov <avkrasnov@salutedevices.com>
>---
> Changelog:
> v1 -> v2:
>  * Place new defines for userspace to the existing file 'vm_sockets.h'
>    instead of creating new one.
> v2 -> v3:
>  * Add comments to describe 'SOL_VSOCK' and 'VSOCK_RECVERR' in the file
>    'vm_sockets.h'.
>  * Reorder includes in 'af_vsock.c' in alphabetical order.
> v3 -> v4:
>  * Update comments for 'SOL_VSOCK' and 'VSOCK_RECVERR' by adding more
>    details.
>
> include/linux/socket.h          |  1 +
> include/uapi/linux/vm_sockets.h | 17 +++++++++++++++++
> net/vmw_vsock/af_vsock.c        |  6 ++++++
> 3 files changed, 24 insertions(+)

Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
diff mbox series

Patch

diff --git a/include/linux/socket.h b/include/linux/socket.h
index 39b74d83c7c4..cfcb7e2c3813 100644
--- a/include/linux/socket.h
+++ b/include/linux/socket.h
@@ -383,6 +383,7 @@  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/include/uapi/linux/vm_sockets.h b/include/uapi/linux/vm_sockets.h
index c60ca33eac59..ed07181d4eff 100644
--- a/include/uapi/linux/vm_sockets.h
+++ b/include/uapi/linux/vm_sockets.h
@@ -191,4 +191,21 @@  struct sockaddr_vm {
 
 #define IOCTL_VM_SOCKETS_GET_LOCAL_CID		_IO(7, 0xb9)
 
+/* MSG_ZEROCOPY notifications are encoded in the standard error format,
+ * sock_extended_err. See Documentation/networking/msg_zerocopy.rst in
+ * kernel source tree for more details.
+ */
+
+/* 'cmsg_level' field value of 'struct cmsghdr' for notification parsing
+ * when MSG_ZEROCOPY flag is used on transmissions.
+ */
+
+#define SOL_VSOCK	287
+
+/* 'cmsg_type' field value of 'struct cmsghdr' for notification parsing
+ * when MSG_ZEROCOPY flag is used on transmissions.
+ */
+
+#define VSOCK_RECVERR	1
+
 #endif /* _UAPI_VM_SOCKETS_H */
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index d841f4de33b0..38486efd3d05 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -89,6 +89,7 @@ 
 #include <linux/types.h>
 #include <linux/bitops.h>
 #include <linux/cred.h>
+#include <linux/errqueue.h>
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/kernel.h>
@@ -110,6 +111,7 @@ 
 #include <linux/workqueue.h>
 #include <net/sock.h>
 #include <net/af_vsock.h>
+#include <uapi/linux/vm_sockets.h>
 
 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr);
 static void vsock_sk_destruct(struct sock *sk);
@@ -2137,6 +2139,10 @@  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, VSOCK_RECVERR);
+
 	vsk = vsock_sk(sk);
 	err = 0;