From: Sowmini Varadhan Date: Fri, 29 May 2015 21:28:08 +0000 (-0400) Subject: net/rds: Add setsockopt support for SO_RDS_TRANSPORT X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=d97dac54bf83b2a3df85fba37595e355627e0f2b;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git net/rds: Add setsockopt support for SO_RDS_TRANSPORT An application may deterministically attach the underlying transport for a PF_RDS socket by invoking setsockopt(2) with the SO_RDS_TRANSPORT option at the SOL_RDS level. The integer argument to setsockopt must be one of the RDS_TRANS_* transport types, e.g., RDS_TRANS_TCP. The option must be specified before invoking bind(2) on the socket, and may only be used once on the socket. An attempt to set the option on a bound socket, or to invoke the option after a successful SO_RDS_TRANSPORT attachment, will return EOPNOTSUPP. Signed-off-by: Sowmini Varadhan Signed-off-by: David S. Miller --- diff --git a/net/rds/af_rds.c b/net/rds/af_rds.c index 3d83641f2861..04877441fb01 100644 --- a/net/rds/af_rds.c +++ b/net/rds/af_rds.c @@ -270,6 +270,28 @@ static int rds_cong_monitor(struct rds_sock *rs, char __user *optval, return ret; } +static int rds_set_transport(struct rds_sock *rs, char __user *optval, + int optlen) +{ + int t_type; + + if (rs->rs_transport) + return -EOPNOTSUPP; /* previously attached to transport */ + + if (optlen != sizeof(int)) + return -EINVAL; + + if (copy_from_user(&t_type, (int __user *)optval, sizeof(t_type))) + return -EFAULT; + + if (t_type < 0 || t_type >= RDS_TRANS_COUNT) + return -EINVAL; + + rs->rs_transport = rds_trans_get(t_type); + + return rs->rs_transport ? 0 : -ENOPROTOOPT; +} + static int rds_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen) { @@ -300,6 +322,11 @@ static int rds_setsockopt(struct socket *sock, int level, int optname, case RDS_CONG_MONITOR: ret = rds_cong_monitor(rs, optval, optlen); break; + case SO_RDS_TRANSPORT: + lock_sock(sock->sk); + ret = rds_set_transport(rs, optval, optlen); + release_sock(sock->sk); + break; default: ret = -ENOPROTOOPT; } diff --git a/net/rds/bind.c b/net/rds/bind.c index a2e6562da751..4ebd29c128b6 100644 --- a/net/rds/bind.c +++ b/net/rds/bind.c @@ -181,6 +181,10 @@ int rds_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) if (ret) goto out; + if (rs->rs_transport) { /* previously bound */ + ret = 0; + goto out; + } trans = rds_trans_get_preferred(sin->sin_addr.s_addr); if (!trans) { ret = -EADDRNOTAVAIL; diff --git a/net/rds/rds.h b/net/rds/rds.h index 76db508f73a1..a33fb4ad3535 100644 --- a/net/rds/rds.h +++ b/net/rds/rds.h @@ -798,6 +798,7 @@ struct rds_transport *rds_trans_get_preferred(__be32 addr); void rds_trans_put(struct rds_transport *trans); unsigned int rds_trans_stats_info_copy(struct rds_info_iterator *iter, unsigned int avail); +struct rds_transport *rds_trans_get(int t_type); int rds_trans_init(void); void rds_trans_exit(void); diff --git a/net/rds/transport.c b/net/rds/transport.c index 7f2ac4fec367..8b4a6cd2c3a7 100644 --- a/net/rds/transport.c +++ b/net/rds/transport.c @@ -101,6 +101,27 @@ struct rds_transport *rds_trans_get_preferred(__be32 addr) return ret; } +struct rds_transport *rds_trans_get(int t_type) +{ + struct rds_transport *ret = NULL; + struct rds_transport *trans; + unsigned int i; + + down_read(&rds_trans_sem); + for (i = 0; i < RDS_TRANS_COUNT; i++) { + trans = transports[i]; + + if (trans && trans->t_type == t_type && + (!trans->t_owner || try_module_get(trans->t_owner))) { + ret = trans; + break; + } + } + up_read(&rds_trans_sem); + + return ret; +} + /* * This returns the number of stats entries in the snapshot and only * copies them using the iter if there is enough space for them. The