Commit b4d84bce authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

inet: set/get simple options locklessly 



Now we have inet->inet_flags, we can set following options
without having to hold the socket lock:

IP_PKTINFO, IP_RECVTTL, IP_RECVTOS, IP_RECVOPTS, IP_RETOPTS,
IP_PASSSEC, IP_RECVORIGDSTADDR, IP_RECVFRAGSIZE.

ip_sock_set_pktinfo() no longer hold the socket lock.

Similarly we can get the following options whithout holding
the socket lock:

IP_PKTINFO, IP_RECVTTL, IP_RECVTOS, IP_RECVOPTS, IP_RETOPTS,
IP_PASSSEC, IP_RECVORIGDSTADDR, IP_CHECKSUM, IP_RECVFRAGSIZE.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Acked-by: default avatarSoheil Hassas Yeganeh <soheil@google.com>
Reviewed-by: default avatarSimon Horman <horms@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent c274af22

net/ipv4/ip_sockglue.c

+62 −56
Original line number Diff line number Diff line
@@ -636,9 +636,7 @@ EXPORT_SYMBOL(ip_sock_set_mtu_discover); 


void ip_sock_set_pktinfo(struct sock *sk)

{

	lock_sock(sk);

	inet_set_bit(PKTINFO, sk);

	release_sock(sk);

}

EXPORT_SYMBOL(ip_sock_set_pktinfo);
@@ -952,6 +950,36 @@ int do_ip_setsockopt(struct sock *sk, int level, int optname, 
	if (ip_mroute_opt(optname))

		return ip_mroute_setsockopt(sk, optname, optval, optlen);



	/* Handle options that can be set without locking the socket. */

	switch (optname) {

	case IP_PKTINFO:

		inet_assign_bit(PKTINFO, sk, val);

		return 0;

	case IP_RECVTTL:

		inet_assign_bit(TTL, sk, val);

		return 0;

	case IP_RECVTOS:

		inet_assign_bit(TOS, sk, val);

		return 0;

	case IP_RECVOPTS:

		inet_assign_bit(RECVOPTS, sk, val);

		return 0;

	case IP_RETOPTS:

		inet_assign_bit(RETOPTS, sk, val);

		return 0;

	case IP_PASSSEC:

		inet_assign_bit(PASSSEC, sk, val);

		return 0;

	case IP_RECVORIGDSTADDR:

		inet_assign_bit(ORIGDSTADDR, sk, val);

		return 0;

	case IP_RECVFRAGSIZE:

		if (sk->sk_type != SOCK_RAW && sk->sk_type != SOCK_DGRAM)

			return -EINVAL;

		inet_assign_bit(RECVFRAGSIZE, sk, val);

		return 0;

	}



	err = 0;

	if (needs_rtnl)

		rtnl_lock();
@@ -991,27 +1019,6 @@ int do_ip_setsockopt(struct sock *sk, int level, int optname, 
			kfree_rcu(old, rcu);

		break;

	}

	case IP_PKTINFO:

		inet_assign_bit(PKTINFO, sk, val);

		break;

	case IP_RECVTTL:

		inet_assign_bit(TTL, sk, val);

		break;

	case IP_RECVTOS:

		inet_assign_bit(TOS, sk, val);

		break;

	case IP_RECVOPTS:

		inet_assign_bit(RECVOPTS, sk, val);

		break;

	case IP_RETOPTS:

		inet_assign_bit(RETOPTS, sk, val);

		break;

	case IP_PASSSEC:

		inet_assign_bit(PASSSEC, sk, val);

		break;

	case IP_RECVORIGDSTADDR:

		inet_assign_bit(ORIGDSTADDR, sk, val);

		break;

	case IP_CHECKSUM:

		if (val) {

			if (!(inet_test_bit(CHECKSUM, sk))) {
@@ -1025,11 +1032,6 @@ int do_ip_setsockopt(struct sock *sk, int level, int optname, 
			}

		}

		break;

	case IP_RECVFRAGSIZE:

		if (sk->sk_type != SOCK_RAW && sk->sk_type != SOCK_DGRAM)

			goto e_inval;

		inet_assign_bit(RECVFRAGSIZE, sk, val);

		break;

	case IP_TOS:	/* This sets both TOS and Precedence */

		__ip_sock_set_tos(sk, val);

		break;
@@ -1544,6 +1546,37 @@ int do_ip_getsockopt(struct sock *sk, int level, int optname, 
	if (len < 0)

		return -EINVAL;



	/* Handle options that can be read without locking the socket. */

	switch (optname) {

	case IP_PKTINFO:

		val = inet_test_bit(PKTINFO, sk);

		goto copyval;

	case IP_RECVTTL:

		val = inet_test_bit(TTL, sk);

		goto copyval;

	case IP_RECVTOS:

		val = inet_test_bit(TOS, sk);

		goto copyval;

	case IP_RECVOPTS:

		val = inet_test_bit(RECVOPTS, sk);

		goto copyval;

	case IP_RETOPTS:

		val = inet_test_bit(RETOPTS, sk);

		goto copyval;

	case IP_PASSSEC:

		val = inet_test_bit(PASSSEC, sk);

		goto copyval;

	case IP_RECVORIGDSTADDR:

		val = inet_test_bit(ORIGDSTADDR, sk);

		goto copyval;

	case IP_CHECKSUM:

		val = inet_test_bit(CHECKSUM, sk);

		goto copyval;

	case IP_RECVFRAGSIZE:

		val = inet_test_bit(RECVFRAGSIZE, sk);

		goto copyval;

	}



	if (needs_rtnl)

		rtnl_lock();

	sockopt_lock_sock(sk);
@@ -1578,33 +1611,6 @@ int do_ip_getsockopt(struct sock *sk, int level, int optname, 
			return -EFAULT;

		return 0;

	}

	case IP_PKTINFO:

		val = inet_test_bit(PKTINFO, sk);

		break;

	case IP_RECVTTL:

		val = inet_test_bit(TTL, sk);

		break;

	case IP_RECVTOS:

		val = inet_test_bit(TOS, sk);

		break;

	case IP_RECVOPTS:

		val = inet_test_bit(RECVOPTS, sk);

		break;

	case IP_RETOPTS:

		val = inet_test_bit(RETOPTS, sk);

		break;

	case IP_PASSSEC:

		val = inet_test_bit(PASSSEC, sk);

		break;

	case IP_RECVORIGDSTADDR:

		val = inet_test_bit(ORIGDSTADDR, sk);

		break;

	case IP_CHECKSUM:

		val = inet_test_bit(CHECKSUM, sk);

		break;

	case IP_RECVFRAGSIZE:

		val = inet_test_bit(RECVFRAGSIZE, sk);

		break;

	case IP_TOS:

		val = inet->tos;

		break;
@@ -1754,7 +1760,7 @@ int do_ip_getsockopt(struct sock *sk, int level, int optname, 
		return -ENOPROTOOPT;

	}

	sockopt_release_sock(sk);



copyval:

	if (len < sizeof(int) && len > 0 && val >= 0 && val <= 255) {

		unsigned char ucval = (unsigned char)val;

		len = 1;