net/rds Add getsockopt support for SO_RDS_TRANSPORT

The currently attached transport for a PF_RDS socket may be obtained
from user space by invoking getsockopt(2) using the SO_RDS_TRANSPORT
option at the SOL_RDS level. The integer optval returned will be one
of the RDS_TRANS_* constants defined in linux/rds.h.

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Sowmini Varadhan 2015-05-29 17:28:09 -04:00 committed by David S. Miller
parent d97dac54bf
commit 8ba38460f3

View file

@ -339,6 +339,7 @@ static int rds_getsockopt(struct socket *sock, int level, int optname,
{
struct rds_sock *rs = rds_sk_to_rs(sock->sk);
int ret = -ENOPROTOOPT, len;
int trans;
if (level != SOL_RDS)
goto out;
@ -364,6 +365,19 @@ static int rds_getsockopt(struct socket *sock, int level, int optname,
else
ret = 0;
break;
case SO_RDS_TRANSPORT:
if (len < sizeof(int)) {
ret = -EINVAL;
break;
}
trans = (rs->rs_transport ? rs->rs_transport->t_type :
RDS_TRANS_NONE); /* unbound */
if (put_user(trans, (int __user *)optval) ||
put_user(sizeof(int), optlen))
ret = -EFAULT;
else
ret = 0;
break;
default:
break;
}