remove kernel_getsockopt

remove kernel_getsockopt

[Christoph Hellwig]

Hi dear maintainers,

this series reduces scope from the last round and just removes
kernel_getsockopt to avoid conflicting with the sctp cleanup series.

[PATCH 1/2] dlm: use the tcp version of accept_from_sock for sctp as well

[Christoph Hellwig]

The only difference between a few missing fixes applied to the SCTP
one is that TCP uses ->getpeername to get the remote address, while
SCTP uses kernel_getsockopt(.. SCTP_PRIMARY_ADDR).  But given that
getpeername is defined to return the primary address for sctp, there
doesn't seem to be any reason for the different way of quering the
peername, or all the code duplication.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/dlm/lowcomms.c | 123 ++--------------------------------------------
 1 file changed, 3 insertions(+), 120 deletions(-)

diff --git a/fs/dlm/lowcomms.c b/fs/dlm/lowcomms.c
index cdfaf4f0e11a0..f13dad0fd9ef3 100644
--- a/fs/dlm/lowcomms.c
+++ b/fs/dlm/lowcomms.c
@@ -724,7 +724,7 @@ static int receive_from_sock(struct connection *con)
 }
 
 /* Listening socket is busy, accept a connection */
-static int tcp_accept_from_sock(struct connection *con)
+static int accept_from_sock(struct connection *con)
 {
 	int result;
 	struct sockaddr_storage peeraddr;
@@ -852,123 +852,6 @@ static int tcp_accept_from_sock(struct connection *con)
 	return result;
 }
 
-static int sctp_accept_from_sock(struct connection *con)
-{
-	/* Check that the new node is in the lockspace */
-	struct sctp_prim prim;
-	int nodeid;
-	int prim_len, ret;
-	int addr_len;
-	struct connection *newcon;
-	struct connection *addcon;
-	struct socket *newsock;
-
-	mutex_lock(&connections_lock);
-	if (!dlm_allow_conn) {
-		mutex_unlock(&connections_lock);
-		return -1;
-	}
-	mutex_unlock(&connections_lock);
-
-	mutex_lock_nested(&con->sock_mutex, 0);
-
-	ret = kernel_accept(con->sock, &newsock, O_NONBLOCK);
-	if (ret < 0)
-		goto accept_err;
-
-	memset(&prim, 0, sizeof(struct sctp_prim));
-	prim_len = sizeof(struct sctp_prim);
-
-	ret = kernel_getsockopt(newsock, IPPROTO_SCTP, SCTP_PRIMARY_ADDR,
-				(char *)&prim, &prim_len);
-	if (ret < 0) {
-		log_print("getsockopt/sctp_primary_addr failed: %d", ret);
-		goto accept_err;
-	}
-
-	make_sockaddr(&prim.ssp_addr, 0, &addr_len);
-	ret = addr_to_nodeid(&prim.ssp_addr, &nodeid);
-	if (ret) {
-		unsigned char *b = (unsigned char *)&prim.ssp_addr;
-
-		log_print("reject connect from unknown addr");
-		print_hex_dump_bytes("ss: ", DUMP_PREFIX_NONE,
-				     b, sizeof(struct sockaddr_storage));
-		goto accept_err;
-	}
-
-	newcon = nodeid2con(nodeid, GFP_NOFS);
-	if (!newcon) {
-		ret = -ENOMEM;
-		goto accept_err;
-	}
-
-	mutex_lock_nested(&newcon->sock_mutex, 1);
-
-	if (newcon->sock) {
-		struct connection *othercon = newcon->othercon;
-
-		if (!othercon) {
-			othercon = kmem_cache_zalloc(con_cache, GFP_NOFS);
-			if (!othercon) {
-				log_print("failed to allocate incoming socket");
-				mutex_unlock(&newcon->sock_mutex);
-				ret = -ENOMEM;
-				goto accept_err;
-			}
-			othercon->nodeid = nodeid;
-			othercon->rx_action = receive_from_sock;
-			mutex_init(&othercon->sock_mutex);
-			INIT_LIST_HEAD(&othercon->writequeue);
-			spin_lock_init(&othercon->writequeue_lock);
-			INIT_WORK(&othercon->swork, process_send_sockets);
-			INIT_WORK(&othercon->rwork, process_recv_sockets);
-			set_bit(CF_IS_OTHERCON, &othercon->flags);
-		}
-		mutex_lock_nested(&othercon->sock_mutex, 2);
-		if (!othercon->sock) {
-			newcon->othercon = othercon;
-			add_sock(newsock, othercon);
-			addcon = othercon;
-			mutex_unlock(&othercon->sock_mutex);
-		} else {
-			printk("Extra connection from node %d attempted\n", nodeid);
-			ret = -EAGAIN;
-			mutex_unlock(&othercon->sock_mutex);
-			mutex_unlock(&newcon->sock_mutex);
-			goto accept_err;
-		}
-	} else {
-		newcon->rx_action = receive_from_sock;
-		add_sock(newsock, newcon);
-		addcon = newcon;
-	}
-
-	log_print("connected to %d", nodeid);
-
-	mutex_unlock(&newcon->sock_mutex);
-
-	/*
-	 * Add it to the active queue in case we got data
-	 * between processing the accept adding the socket
-	 * to the read_sockets list
-	 */
-	if (!test_and_set_bit(CF_READ_PENDING, &addcon->flags))
-		queue_work(recv_workqueue, &addcon->rwork);
-	mutex_unlock(&con->sock_mutex);
-
-	return 0;
-
-accept_err:
-	mutex_unlock(&con->sock_mutex);
-	if (newsock)
-		sock_release(newsock);
-	if (ret != -EAGAIN)
-		log_print("error accepting connection from node: %d", ret);
-
-	return ret;
-}
-
 static void free_entry(struct writequeue_entry *e)
 {
 	__free_page(e->page);
@@ -1253,7 +1136,7 @@ static struct socket *tcp_create_listen_sock(struct connection *con,
 	write_lock_bh(&sock->sk->sk_callback_lock);
 	sock->sk->sk_user_data = con;
 	save_listen_callbacks(sock);
-	con->rx_action = tcp_accept_from_sock;
+	con->rx_action = accept_from_sock;
 	con->connect_action = tcp_connect_to_sock;
 	write_unlock_bh(&sock->sk->sk_callback_lock);
 
@@ -1340,7 +1223,7 @@ static int sctp_listen_for_all(void)
 	save_listen_callbacks(sock);
 	con->sock = sock;
 	con->sock->sk->sk_data_ready = lowcomms_data_ready;
-	con->rx_action = sctp_accept_from_sock;
+	con->rx_action = accept_from_sock;
 	con->connect_action = sctp_connect_to_sock;
 
 	write_unlock_bh(&sock->sk->sk_callback_lock);
-- 
2.26.2

[PATCH 2/2] net: remove kernel_getsockopt

[Christoph Hellwig]

No users left.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 include/linux/net.h |  2 --
 net/socket.c        | 34 ----------------------------------
 2 files changed, 36 deletions(-)

diff --git a/include/linux/net.h b/include/linux/net.h
index 6451425e828f5..74ef5d7315f70 100644
--- a/include/linux/net.h
+++ b/include/linux/net.h
@@ -303,8 +303,6 @@ int kernel_connect(struct socket *sock, struct sockaddr *addr, int addrlen,
 		   int flags);
 int kernel_getsockname(struct socket *sock, struct sockaddr *addr);
 int kernel_getpeername(struct socket *sock, struct sockaddr *addr);
-int kernel_getsockopt(struct socket *sock, int level, int optname, char *optval,
-		      int *optlen);
 int kernel_setsockopt(struct socket *sock, int level, int optname, char *optval,
 		      unsigned int optlen);
 int kernel_sendpage(struct socket *sock, struct page *page, int offset,
diff --git a/net/socket.c b/net/socket.c
index 80422fc3c836e..81a98b6cbd087 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -3624,40 +3624,6 @@ int kernel_getpeername(struct socket *sock, struct sockaddr *addr)
 }
 EXPORT_SYMBOL(kernel_getpeername);
 
-/**
- *	kernel_getsockopt - get a socket option (kernel space)
- *	@sock: socket
- *	@level: API level (SOL_SOCKET, ...)
- *	@optname: option tag
- *	@optval: option value
- *	@optlen: option length
- *
- *	Assigns the option length to @optlen.
- *	Returns 0 or an error.
- */
-
-int kernel_getsockopt(struct socket *sock, int level, int optname,
-			char *optval, int *optlen)
-{
-	mm_segment_t oldfs = get_fs();
-	char __user *uoptval;
-	int __user *uoptlen;
-	int err;
-
-	uoptval = (char __user __force *) optval;
-	uoptlen = (int __user __force *) optlen;
-
-	set_fs(KERNEL_DS);
-	if (level == SOL_SOCKET)
-		err = sock_getsockopt(sock, level, optname, uoptval, uoptlen);
-	else
-		err = sock->ops->getsockopt(sock, level, optname, uoptval,
-					    uoptlen);
-	set_fs(oldfs);
-	return err;
-}
-EXPORT_SYMBOL(kernel_getsockopt);
-
 /**
  *	kernel_setsockopt - set a socket option (kernel space)
  *	@sock: socket
-- 
2.26.2

Re: remove kernel_getsockopt

[David Miller]

From: Christoph Hellwig <hch@lst.de>
Date: Wed, 27 May 2020 20:22:27 +0200

> this series reduces scope from the last round and just removes
> kernel_getsockopt to avoid conflicting with the sctp cleanup series.

Series applied to net-next, thanks.