net: dccp: Add SIOCOUTQ IOCTL support (send buffer fill) (749c08f8) · Commits · 戴 / test

This adds support for the SIOCOUTQ IOCTL to get the send buffer fill of a DCCP socket, like UDP and TCP sockets already have. Regarding the used data field: DCCP uses per packet sequence numbers, not per byte, so sequence numbers can't be used like in TCP. sk_wmem_queued is not used by DCCP and always 0, even in test on highly congested paths. Therefore this uses sk_wmem_alloc like in UDP. Signed-off-by:

Richard Sailer <richard_siegfried@systemli.org> Signed-off-by:

David S. Miller <davem@davemloft.net>

Documentation/networking/dccp.rst

+3 −0

Original line number	Diff line number	Diff line
		@@ -192,6 +192,9 @@ FIONREAD
		Works as in udp(7): returns in the ``int`` argument pointer the size of
		the next pending datagram in bytes, or 0 when no datagram is pending.

		SIOCOUTQ
		Returns the number of unsent data bytes in the socket send queue as ``int``
		into the buffer specified by the argument pointer.

		Other tunables
		==============

net/dccp/proto.c

+9 −0

Original line number	Diff line number	Diff line
		@@ -375,6 +375,15 @@ int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg)
		goto out;

		switch (cmd) {
		case SIOCOUTQ: {
		int amount = sk_wmem_alloc_get(sk);
		/* Using sk_wmem_alloc here because sk_wmem_queued is not used by DCCP and
		* always 0, comparably to UDP.
		*/

		rc = put_user(amount, (int __user *)arg);
		}
		break;
		case SIOCINQ: {
		struct sk_buff *skb;
		unsigned long amount = 0;

Admin message