summaryrefslogtreecommitdiffstats
path: root/net/sunrpc/svcsock.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/sunrpc/svcsock.c')
-rw-r--r--net/sunrpc/svcsock.c1644
1 files changed, 1644 insertions, 0 deletions
diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
new file mode 100644
index 0000000000..e0ce427627
--- /dev/null
+++ b/net/sunrpc/svcsock.c
@@ -0,0 +1,1644 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * linux/net/sunrpc/svcsock.c
+ *
+ * These are the RPC server socket internals.
+ *
+ * The server scheduling algorithm does not always distribute the load
+ * evenly when servicing a single client. May need to modify the
+ * svc_xprt_enqueue procedure...
+ *
+ * TCP support is largely untested and may be a little slow. The problem
+ * is that we currently do two separate recvfrom's, one for the 4-byte
+ * record length, and the second for the actual record. This could possibly
+ * be improved by always reading a minimum size of around 100 bytes and
+ * tucking any superfluous bytes away in a temporary store. Still, that
+ * leaves write requests out in the rain. An alternative may be to peek at
+ * the first skb in the queue, and if it matches the next TCP sequence
+ * number, to extract the record marker. Yuck.
+ *
+ * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fcntl.h>
+#include <linux/net.h>
+#include <linux/in.h>
+#include <linux/inet.h>
+#include <linux/udp.h>
+#include <linux/tcp.h>
+#include <linux/unistd.h>
+#include <linux/slab.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <linux/file.h>
+#include <linux/freezer.h>
+#include <linux/bvec.h>
+
+#include <net/sock.h>
+#include <net/checksum.h>
+#include <net/ip.h>
+#include <net/ipv6.h>
+#include <net/udp.h>
+#include <net/tcp.h>
+#include <net/tcp_states.h>
+#include <net/tls_prot.h>
+#include <net/handshake.h>
+#include <linux/uaccess.h>
+#include <linux/highmem.h>
+#include <asm/ioctls.h>
+#include <linux/key.h>
+
+#include <linux/sunrpc/types.h>
+#include <linux/sunrpc/clnt.h>
+#include <linux/sunrpc/xdr.h>
+#include <linux/sunrpc/msg_prot.h>
+#include <linux/sunrpc/svcsock.h>
+#include <linux/sunrpc/stats.h>
+#include <linux/sunrpc/xprt.h>
+
+#include <trace/events/sock.h>
+#include <trace/events/sunrpc.h>
+
+#include "socklib.h"
+#include "sunrpc.h"
+
+#define RPCDBG_FACILITY RPCDBG_SVCXPRT
+
+/* To-do: to avoid tying up an nfsd thread while waiting for a
+ * handshake request, the request could instead be deferred.
+ */
+enum {
+ SVC_HANDSHAKE_TO = 5U * HZ
+};
+
+static struct svc_sock *svc_setup_socket(struct svc_serv *, struct socket *,
+ int flags);
+static int svc_udp_recvfrom(struct svc_rqst *);
+static int svc_udp_sendto(struct svc_rqst *);
+static void svc_sock_detach(struct svc_xprt *);
+static void svc_tcp_sock_detach(struct svc_xprt *);
+static void svc_sock_free(struct svc_xprt *);
+
+static struct svc_xprt *svc_create_socket(struct svc_serv *, int,
+ struct net *, struct sockaddr *,
+ int, int);
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+static struct lock_class_key svc_key[2];
+static struct lock_class_key svc_slock_key[2];
+
+static void svc_reclassify_socket(struct socket *sock)
+{
+ struct sock *sk = sock->sk;
+
+ if (WARN_ON_ONCE(!sock_allow_reclassification(sk)))
+ return;
+
+ switch (sk->sk_family) {
+ case AF_INET:
+ sock_lock_init_class_and_name(sk, "slock-AF_INET-NFSD",
+ &svc_slock_key[0],
+ "sk_xprt.xpt_lock-AF_INET-NFSD",
+ &svc_key[0]);
+ break;
+
+ case AF_INET6:
+ sock_lock_init_class_and_name(sk, "slock-AF_INET6-NFSD",
+ &svc_slock_key[1],
+ "sk_xprt.xpt_lock-AF_INET6-NFSD",
+ &svc_key[1]);
+ break;
+
+ default:
+ BUG();
+ }
+}
+#else
+static void svc_reclassify_socket(struct socket *sock)
+{
+}
+#endif
+
+/**
+ * svc_tcp_release_ctxt - Release transport-related resources
+ * @xprt: the transport which owned the context
+ * @ctxt: the context from rqstp->rq_xprt_ctxt or dr->xprt_ctxt
+ *
+ */
+static void svc_tcp_release_ctxt(struct svc_xprt *xprt, void *ctxt)
+{
+}
+
+/**
+ * svc_udp_release_ctxt - Release transport-related resources
+ * @xprt: the transport which owned the context
+ * @ctxt: the context from rqstp->rq_xprt_ctxt or dr->xprt_ctxt
+ *
+ */
+static void svc_udp_release_ctxt(struct svc_xprt *xprt, void *ctxt)
+{
+ struct sk_buff *skb = ctxt;
+
+ if (skb)
+ consume_skb(skb);
+}
+
+union svc_pktinfo_u {
+ struct in_pktinfo pkti;
+ struct in6_pktinfo pkti6;
+};
+#define SVC_PKTINFO_SPACE \
+ CMSG_SPACE(sizeof(union svc_pktinfo_u))
+
+static void svc_set_cmsg_data(struct svc_rqst *rqstp, struct cmsghdr *cmh)
+{
+ struct svc_sock *svsk =
+ container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
+ switch (svsk->sk_sk->sk_family) {
+ case AF_INET: {
+ struct in_pktinfo *pki = CMSG_DATA(cmh);
+
+ cmh->cmsg_level = SOL_IP;
+ cmh->cmsg_type = IP_PKTINFO;
+ pki->ipi_ifindex = 0;
+ pki->ipi_spec_dst.s_addr =
+ svc_daddr_in(rqstp)->sin_addr.s_addr;
+ cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
+ }
+ break;
+
+ case AF_INET6: {
+ struct in6_pktinfo *pki = CMSG_DATA(cmh);
+ struct sockaddr_in6 *daddr = svc_daddr_in6(rqstp);
+
+ cmh->cmsg_level = SOL_IPV6;
+ cmh->cmsg_type = IPV6_PKTINFO;
+ pki->ipi6_ifindex = daddr->sin6_scope_id;
+ pki->ipi6_addr = daddr->sin6_addr;
+ cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
+ }
+ break;
+ }
+}
+
+static int svc_sock_result_payload(struct svc_rqst *rqstp, unsigned int offset,
+ unsigned int length)
+{
+ return 0;
+}
+
+/*
+ * Report socket names for nfsdfs
+ */
+static int svc_one_sock_name(struct svc_sock *svsk, char *buf, int remaining)
+{
+ const struct sock *sk = svsk->sk_sk;
+ const char *proto_name = sk->sk_protocol == IPPROTO_UDP ?
+ "udp" : "tcp";
+ int len;
+
+ switch (sk->sk_family) {
+ case PF_INET:
+ len = snprintf(buf, remaining, "ipv4 %s %pI4 %d\n",
+ proto_name,
+ &inet_sk(sk)->inet_rcv_saddr,
+ inet_sk(sk)->inet_num);
+ break;
+#if IS_ENABLED(CONFIG_IPV6)
+ case PF_INET6:
+ len = snprintf(buf, remaining, "ipv6 %s %pI6 %d\n",
+ proto_name,
+ &sk->sk_v6_rcv_saddr,
+ inet_sk(sk)->inet_num);
+ break;
+#endif
+ default:
+ len = snprintf(buf, remaining, "*unknown-%d*\n",
+ sk->sk_family);
+ }
+
+ if (len >= remaining) {
+ *buf = '\0';
+ return -ENAMETOOLONG;
+ }
+ return len;
+}
+
+static int
+svc_tcp_sock_process_cmsg(struct socket *sock, struct msghdr *msg,
+ struct cmsghdr *cmsg, int ret)
+{
+ u8 content_type = tls_get_record_type(sock->sk, cmsg);
+ u8 level, description;
+
+ switch (content_type) {
+ case 0:
+ break;
+ case TLS_RECORD_TYPE_DATA:
+ /* TLS sets EOR at the end of each application data
+ * record, even though there might be more frames
+ * waiting to be decrypted.
+ */
+ msg->msg_flags &= ~MSG_EOR;
+ break;
+ case TLS_RECORD_TYPE_ALERT:
+ tls_alert_recv(sock->sk, msg, &level, &description);
+ ret = (level == TLS_ALERT_LEVEL_FATAL) ?
+ -ENOTCONN : -EAGAIN;
+ break;
+ default:
+ /* discard this record type */
+ ret = -EAGAIN;
+ }
+ return ret;
+}
+
+static int
+svc_tcp_sock_recv_cmsg(struct svc_sock *svsk, struct msghdr *msg)
+{
+ union {
+ struct cmsghdr cmsg;
+ u8 buf[CMSG_SPACE(sizeof(u8))];
+ } u;
+ struct socket *sock = svsk->sk_sock;
+ int ret;
+
+ msg->msg_control = &u;
+ msg->msg_controllen = sizeof(u);
+ ret = sock_recvmsg(sock, msg, MSG_DONTWAIT);
+ if (unlikely(msg->msg_controllen != sizeof(u)))
+ ret = svc_tcp_sock_process_cmsg(sock, msg, &u.cmsg, ret);
+ return ret;
+}
+
+#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
+static void svc_flush_bvec(const struct bio_vec *bvec, size_t size, size_t seek)
+{
+ struct bvec_iter bi = {
+ .bi_size = size + seek,
+ };
+ struct bio_vec bv;
+
+ bvec_iter_advance(bvec, &bi, seek & PAGE_MASK);
+ for_each_bvec(bv, bvec, bi, bi)
+ flush_dcache_page(bv.bv_page);
+}
+#else
+static inline void svc_flush_bvec(const struct bio_vec *bvec, size_t size,
+ size_t seek)
+{
+}
+#endif
+
+/*
+ * Read from @rqstp's transport socket. The incoming message fills whole
+ * pages in @rqstp's rq_pages array until the last page of the message
+ * has been received into a partial page.
+ */
+static ssize_t svc_tcp_read_msg(struct svc_rqst *rqstp, size_t buflen,
+ size_t seek)
+{
+ struct svc_sock *svsk =
+ container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
+ struct bio_vec *bvec = rqstp->rq_bvec;
+ struct msghdr msg = { NULL };
+ unsigned int i;
+ ssize_t len;
+ size_t t;
+
+ clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
+
+ for (i = 0, t = 0; t < buflen; i++, t += PAGE_SIZE)
+ bvec_set_page(&bvec[i], rqstp->rq_pages[i], PAGE_SIZE, 0);
+ rqstp->rq_respages = &rqstp->rq_pages[i];
+ rqstp->rq_next_page = rqstp->rq_respages + 1;
+
+ iov_iter_bvec(&msg.msg_iter, ITER_DEST, bvec, i, buflen);
+ if (seek) {
+ iov_iter_advance(&msg.msg_iter, seek);
+ buflen -= seek;
+ }
+ len = svc_tcp_sock_recv_cmsg(svsk, &msg);
+ if (len > 0)
+ svc_flush_bvec(bvec, len, seek);
+
+ /* If we read a full record, then assume there may be more
+ * data to read (stream based sockets only!)
+ */
+ if (len == buflen)
+ set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
+
+ return len;
+}
+
+/*
+ * Set socket snd and rcv buffer lengths
+ */
+static void svc_sock_setbufsize(struct svc_sock *svsk, unsigned int nreqs)
+{
+ unsigned int max_mesg = svsk->sk_xprt.xpt_server->sv_max_mesg;
+ struct socket *sock = svsk->sk_sock;
+
+ nreqs = min(nreqs, INT_MAX / 2 / max_mesg);
+
+ lock_sock(sock->sk);
+ sock->sk->sk_sndbuf = nreqs * max_mesg * 2;
+ sock->sk->sk_rcvbuf = nreqs * max_mesg * 2;
+ sock->sk->sk_write_space(sock->sk);
+ release_sock(sock->sk);
+}
+
+static void svc_sock_secure_port(struct svc_rqst *rqstp)
+{
+ if (svc_port_is_privileged(svc_addr(rqstp)))
+ set_bit(RQ_SECURE, &rqstp->rq_flags);
+ else
+ clear_bit(RQ_SECURE, &rqstp->rq_flags);
+}
+
+/*
+ * INET callback when data has been received on the socket.
+ */
+static void svc_data_ready(struct sock *sk)
+{
+ struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
+
+ trace_sk_data_ready(sk);
+
+ if (svsk) {
+ /* Refer to svc_setup_socket() for details. */
+ rmb();
+ svsk->sk_odata(sk);
+ trace_svcsock_data_ready(&svsk->sk_xprt, 0);
+ if (test_bit(XPT_HANDSHAKE, &svsk->sk_xprt.xpt_flags))
+ return;
+ if (!test_and_set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags))
+ svc_xprt_enqueue(&svsk->sk_xprt);
+ }
+}
+
+/*
+ * INET callback when space is newly available on the socket.
+ */
+static void svc_write_space(struct sock *sk)
+{
+ struct svc_sock *svsk = (struct svc_sock *)(sk->sk_user_data);
+
+ if (svsk) {
+ /* Refer to svc_setup_socket() for details. */
+ rmb();
+ trace_svcsock_write_space(&svsk->sk_xprt, 0);
+ svsk->sk_owspace(sk);
+ svc_xprt_enqueue(&svsk->sk_xprt);
+ }
+}
+
+static int svc_tcp_has_wspace(struct svc_xprt *xprt)
+{
+ struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
+
+ if (test_bit(XPT_LISTENER, &xprt->xpt_flags))
+ return 1;
+ return !test_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
+}
+
+static void svc_tcp_kill_temp_xprt(struct svc_xprt *xprt)
+{
+ struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
+
+ sock_no_linger(svsk->sk_sock->sk);
+}
+
+/**
+ * svc_tcp_handshake_done - Handshake completion handler
+ * @data: address of xprt to wake
+ * @status: status of handshake
+ * @peerid: serial number of key containing the remote peer's identity
+ *
+ * If a security policy is specified as an export option, we don't
+ * have a specific export here to check. So we set a "TLS session
+ * is present" flag on the xprt and let an upper layer enforce local
+ * security policy.
+ */
+static void svc_tcp_handshake_done(void *data, int status, key_serial_t peerid)
+{
+ struct svc_xprt *xprt = data;
+ struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
+
+ if (!status) {
+ if (peerid != TLS_NO_PEERID)
+ set_bit(XPT_PEER_AUTH, &xprt->xpt_flags);
+ set_bit(XPT_TLS_SESSION, &xprt->xpt_flags);
+ }
+ clear_bit(XPT_HANDSHAKE, &xprt->xpt_flags);
+ complete_all(&svsk->sk_handshake_done);
+}
+
+/**
+ * svc_tcp_handshake - Perform a transport-layer security handshake
+ * @xprt: connected transport endpoint
+ *
+ */
+static void svc_tcp_handshake(struct svc_xprt *xprt)
+{
+ struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
+ struct sock *sk = svsk->sk_sock->sk;
+ struct tls_handshake_args args = {
+ .ta_sock = svsk->sk_sock,
+ .ta_done = svc_tcp_handshake_done,
+ .ta_data = xprt,
+ };
+ int ret;
+
+ trace_svc_tls_upcall(xprt);
+
+ clear_bit(XPT_TLS_SESSION, &xprt->xpt_flags);
+ init_completion(&svsk->sk_handshake_done);
+
+ ret = tls_server_hello_x509(&args, GFP_KERNEL);
+ if (ret) {
+ trace_svc_tls_not_started(xprt);
+ goto out_failed;
+ }
+
+ ret = wait_for_completion_interruptible_timeout(&svsk->sk_handshake_done,
+ SVC_HANDSHAKE_TO);
+ if (ret <= 0) {
+ if (tls_handshake_cancel(sk)) {
+ trace_svc_tls_timed_out(xprt);
+ goto out_close;
+ }
+ }
+
+ if (!test_bit(XPT_TLS_SESSION, &xprt->xpt_flags)) {
+ trace_svc_tls_unavailable(xprt);
+ goto out_close;
+ }
+
+ /* Mark the transport ready in case the remote sent RPC
+ * traffic before the kernel received the handshake
+ * completion downcall.
+ */
+ set_bit(XPT_DATA, &xprt->xpt_flags);
+ svc_xprt_enqueue(xprt);
+ return;
+
+out_close:
+ set_bit(XPT_CLOSE, &xprt->xpt_flags);
+out_failed:
+ clear_bit(XPT_HANDSHAKE, &xprt->xpt_flags);
+ set_bit(XPT_DATA, &xprt->xpt_flags);
+ svc_xprt_enqueue(xprt);
+}
+
+/*
+ * See net/ipv6/ip_sockglue.c : ip_cmsg_recv_pktinfo
+ */
+static int svc_udp_get_dest_address4(struct svc_rqst *rqstp,
+ struct cmsghdr *cmh)
+{
+ struct in_pktinfo *pki = CMSG_DATA(cmh);
+ struct sockaddr_in *daddr = svc_daddr_in(rqstp);
+
+ if (cmh->cmsg_type != IP_PKTINFO)
+ return 0;
+
+ daddr->sin_family = AF_INET;
+ daddr->sin_addr.s_addr = pki->ipi_spec_dst.s_addr;
+ return 1;
+}
+
+/*
+ * See net/ipv6/datagram.c : ip6_datagram_recv_ctl
+ */
+static int svc_udp_get_dest_address6(struct svc_rqst *rqstp,
+ struct cmsghdr *cmh)
+{
+ struct in6_pktinfo *pki = CMSG_DATA(cmh);
+ struct sockaddr_in6 *daddr = svc_daddr_in6(rqstp);
+
+ if (cmh->cmsg_type != IPV6_PKTINFO)
+ return 0;
+
+ daddr->sin6_family = AF_INET6;
+ daddr->sin6_addr = pki->ipi6_addr;
+ daddr->sin6_scope_id = pki->ipi6_ifindex;
+ return 1;
+}
+
+/*
+ * Copy the UDP datagram's destination address to the rqstp structure.
+ * The 'destination' address in this case is the address to which the
+ * peer sent the datagram, i.e. our local address. For multihomed
+ * hosts, this can change from msg to msg. Note that only the IP
+ * address changes, the port number should remain the same.
+ */
+static int svc_udp_get_dest_address(struct svc_rqst *rqstp,
+ struct cmsghdr *cmh)
+{
+ switch (cmh->cmsg_level) {
+ case SOL_IP:
+ return svc_udp_get_dest_address4(rqstp, cmh);
+ case SOL_IPV6:
+ return svc_udp_get_dest_address6(rqstp, cmh);
+ }
+
+ return 0;
+}
+
+/**
+ * svc_udp_recvfrom - Receive a datagram from a UDP socket.
+ * @rqstp: request structure into which to receive an RPC Call
+ *
+ * Called in a loop when XPT_DATA has been set.
+ *
+ * Returns:
+ * On success, the number of bytes in a received RPC Call, or
+ * %0 if a complete RPC Call message was not ready to return
+ */
+static int svc_udp_recvfrom(struct svc_rqst *rqstp)
+{
+ struct svc_sock *svsk =
+ container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
+ struct svc_serv *serv = svsk->sk_xprt.xpt_server;
+ struct sk_buff *skb;
+ union {
+ struct cmsghdr hdr;
+ long all[SVC_PKTINFO_SPACE / sizeof(long)];
+ } buffer;
+ struct cmsghdr *cmh = &buffer.hdr;
+ struct msghdr msg = {
+ .msg_name = svc_addr(rqstp),
+ .msg_control = cmh,
+ .msg_controllen = sizeof(buffer),
+ .msg_flags = MSG_DONTWAIT,
+ };
+ size_t len;
+ int err;
+
+ if (test_and_clear_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags))
+ /* udp sockets need large rcvbuf as all pending
+ * requests are still in that buffer. sndbuf must
+ * also be large enough that there is enough space
+ * for one reply per thread. We count all threads
+ * rather than threads in a particular pool, which
+ * provides an upper bound on the number of threads
+ * which will access the socket.
+ */
+ svc_sock_setbufsize(svsk, serv->sv_nrthreads + 3);
+
+ clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
+ err = kernel_recvmsg(svsk->sk_sock, &msg, NULL,
+ 0, 0, MSG_PEEK | MSG_DONTWAIT);
+ if (err < 0)
+ goto out_recv_err;
+ skb = skb_recv_udp(svsk->sk_sk, MSG_DONTWAIT, &err);
+ if (!skb)
+ goto out_recv_err;
+
+ len = svc_addr_len(svc_addr(rqstp));
+ rqstp->rq_addrlen = len;
+ if (skb->tstamp == 0) {
+ skb->tstamp = ktime_get_real();
+ /* Don't enable netstamp, sunrpc doesn't
+ need that much accuracy */
+ }
+ sock_write_timestamp(svsk->sk_sk, skb->tstamp);
+ set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); /* there may be more data... */
+
+ len = skb->len;
+ rqstp->rq_arg.len = len;
+ trace_svcsock_udp_recv(&svsk->sk_xprt, len);
+
+ rqstp->rq_prot = IPPROTO_UDP;
+
+ if (!svc_udp_get_dest_address(rqstp, cmh))
+ goto out_cmsg_err;
+ rqstp->rq_daddrlen = svc_addr_len(svc_daddr(rqstp));
+
+ if (skb_is_nonlinear(skb)) {
+ /* we have to copy */
+ local_bh_disable();
+ if (csum_partial_copy_to_xdr(&rqstp->rq_arg, skb))
+ goto out_bh_enable;
+ local_bh_enable();
+ consume_skb(skb);
+ } else {
+ /* we can use it in-place */
+ rqstp->rq_arg.head[0].iov_base = skb->data;
+ rqstp->rq_arg.head[0].iov_len = len;
+ if (skb_checksum_complete(skb))
+ goto out_free;
+ rqstp->rq_xprt_ctxt = skb;
+ }
+
+ rqstp->rq_arg.page_base = 0;
+ if (len <= rqstp->rq_arg.head[0].iov_len) {
+ rqstp->rq_arg.head[0].iov_len = len;
+ rqstp->rq_arg.page_len = 0;
+ rqstp->rq_respages = rqstp->rq_pages+1;
+ } else {
+ rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len;
+ rqstp->rq_respages = rqstp->rq_pages + 1 +
+ DIV_ROUND_UP(rqstp->rq_arg.page_len, PAGE_SIZE);
+ }
+ rqstp->rq_next_page = rqstp->rq_respages+1;
+
+ if (serv->sv_stats)
+ serv->sv_stats->netudpcnt++;
+
+ svc_sock_secure_port(rqstp);
+ svc_xprt_received(rqstp->rq_xprt);
+ return len;
+
+out_recv_err:
+ if (err != -EAGAIN) {
+ /* possibly an icmp error */
+ set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
+ }
+ trace_svcsock_udp_recv_err(&svsk->sk_xprt, err);
+ goto out_clear_busy;
+out_cmsg_err:
+ net_warn_ratelimited("svc: received unknown control message %d/%d; dropping RPC reply datagram\n",
+ cmh->cmsg_level, cmh->cmsg_type);
+ goto out_free;
+out_bh_enable:
+ local_bh_enable();
+out_free:
+ kfree_skb(skb);
+out_clear_busy:
+ svc_xprt_received(rqstp->rq_xprt);
+ return 0;
+}
+
+/**
+ * svc_udp_sendto - Send out a reply on a UDP socket
+ * @rqstp: completed svc_rqst
+ *
+ * xpt_mutex ensures @rqstp's whole message is written to the socket
+ * without interruption.
+ *
+ * Returns the number of bytes sent, or a negative errno.
+ */
+static int svc_udp_sendto(struct svc_rqst *rqstp)
+{
+ struct svc_xprt *xprt = rqstp->rq_xprt;
+ struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
+ struct xdr_buf *xdr = &rqstp->rq_res;
+ union {
+ struct cmsghdr hdr;
+ long all[SVC_PKTINFO_SPACE / sizeof(long)];
+ } buffer;
+ struct cmsghdr *cmh = &buffer.hdr;
+ struct msghdr msg = {
+ .msg_name = &rqstp->rq_addr,
+ .msg_namelen = rqstp->rq_addrlen,
+ .msg_control = cmh,
+ .msg_flags = MSG_SPLICE_PAGES,
+ .msg_controllen = sizeof(buffer),
+ };
+ unsigned int count;
+ int err;
+
+ svc_udp_release_ctxt(xprt, rqstp->rq_xprt_ctxt);
+ rqstp->rq_xprt_ctxt = NULL;
+
+ svc_set_cmsg_data(rqstp, cmh);
+
+ mutex_lock(&xprt->xpt_mutex);
+
+ if (svc_xprt_is_dead(xprt))
+ goto out_notconn;
+
+ count = xdr_buf_to_bvec(rqstp->rq_bvec,
+ ARRAY_SIZE(rqstp->rq_bvec), xdr);
+
+ iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, rqstp->rq_bvec,
+ count, rqstp->rq_res.len);
+ err = sock_sendmsg(svsk->sk_sock, &msg);
+ if (err == -ECONNREFUSED) {
+ /* ICMP error on earlier request. */
+ iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, rqstp->rq_bvec,
+ count, rqstp->rq_res.len);
+ err = sock_sendmsg(svsk->sk_sock, &msg);
+ }
+
+ trace_svcsock_udp_send(xprt, err);
+
+ mutex_unlock(&xprt->xpt_mutex);
+ return err;
+
+out_notconn:
+ mutex_unlock(&xprt->xpt_mutex);
+ return -ENOTCONN;
+}
+
+static int svc_udp_has_wspace(struct svc_xprt *xprt)
+{
+ struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
+ struct svc_serv *serv = xprt->xpt_server;
+ unsigned long required;
+
+ /*
+ * Set the SOCK_NOSPACE flag before checking the available
+ * sock space.
+ */
+ set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
+ required = atomic_read(&svsk->sk_xprt.xpt_reserved) + serv->sv_max_mesg;
+ if (required*2 > sock_wspace(svsk->sk_sk))
+ return 0;
+ clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
+ return 1;
+}
+
+static struct svc_xprt *svc_udp_accept(struct svc_xprt *xprt)
+{
+ BUG();
+ return NULL;
+}
+
+static void svc_udp_kill_temp_xprt(struct svc_xprt *xprt)
+{
+}
+
+static struct svc_xprt *svc_udp_create(struct svc_serv *serv,
+ struct net *net,
+ struct sockaddr *sa, int salen,
+ int flags)
+{
+ return svc_create_socket(serv, IPPROTO_UDP, net, sa, salen, flags);
+}
+
+static const struct svc_xprt_ops svc_udp_ops = {
+ .xpo_create = svc_udp_create,
+ .xpo_recvfrom = svc_udp_recvfrom,
+ .xpo_sendto = svc_udp_sendto,
+ .xpo_result_payload = svc_sock_result_payload,
+ .xpo_release_ctxt = svc_udp_release_ctxt,
+ .xpo_detach = svc_sock_detach,
+ .xpo_free = svc_sock_free,
+ .xpo_has_wspace = svc_udp_has_wspace,
+ .xpo_accept = svc_udp_accept,
+ .xpo_kill_temp_xprt = svc_udp_kill_temp_xprt,
+};
+
+static struct svc_xprt_class svc_udp_class = {
+ .xcl_name = "udp",
+ .xcl_owner = THIS_MODULE,
+ .xcl_ops = &svc_udp_ops,
+ .xcl_max_payload = RPCSVC_MAXPAYLOAD_UDP,
+ .xcl_ident = XPRT_TRANSPORT_UDP,
+};
+
+static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv)
+{
+ svc_xprt_init(sock_net(svsk->sk_sock->sk), &svc_udp_class,
+ &svsk->sk_xprt, serv);
+ clear_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
+ svsk->sk_sk->sk_data_ready = svc_data_ready;
+ svsk->sk_sk->sk_write_space = svc_write_space;
+
+ /* initialise setting must have enough space to
+ * receive and respond to one request.
+ * svc_udp_recvfrom will re-adjust if necessary
+ */
+ svc_sock_setbufsize(svsk, 3);
+
+ /* data might have come in before data_ready set up */
+ set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
+ set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
+
+ /* make sure we get destination address info */
+ switch (svsk->sk_sk->sk_family) {
+ case AF_INET:
+ ip_sock_set_pktinfo(svsk->sk_sock->sk);
+ break;
+ case AF_INET6:
+ ip6_sock_set_recvpktinfo(svsk->sk_sock->sk);
+ break;
+ default:
+ BUG();
+ }
+}
+
+/*
+ * A data_ready event on a listening socket means there's a connection
+ * pending. Do not use state_change as a substitute for it.
+ */
+static void svc_tcp_listen_data_ready(struct sock *sk)
+{
+ struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
+
+ trace_sk_data_ready(sk);
+
+ /*
+ * This callback may called twice when a new connection
+ * is established as a child socket inherits everything
+ * from a parent LISTEN socket.
+ * 1) data_ready method of the parent socket will be called
+ * when one of child sockets become ESTABLISHED.
+ * 2) data_ready method of the child socket may be called
+ * when it receives data before the socket is accepted.
+ * In case of 2, we should ignore it silently and DO NOT
+ * dereference svsk.
+ */
+ if (sk->sk_state != TCP_LISTEN)
+ return;
+
+ if (svsk) {
+ /* Refer to svc_setup_socket() for details. */
+ rmb();
+ svsk->sk_odata(sk);
+ set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
+ svc_xprt_enqueue(&svsk->sk_xprt);
+ }
+}
+
+/*
+ * A state change on a connected socket means it's dying or dead.
+ */
+static void svc_tcp_state_change(struct sock *sk)
+{
+ struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
+
+ if (svsk) {
+ /* Refer to svc_setup_socket() for details. */
+ rmb();
+ svsk->sk_ostate(sk);
+ trace_svcsock_tcp_state(&svsk->sk_xprt, svsk->sk_sock);
+ if (sk->sk_state != TCP_ESTABLISHED)
+ svc_xprt_deferred_close(&svsk->sk_xprt);
+ }
+}
+
+/*
+ * Accept a TCP connection
+ */
+static struct svc_xprt *svc_tcp_accept(struct svc_xprt *xprt)
+{
+ struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
+ struct sockaddr_storage addr;
+ struct sockaddr *sin = (struct sockaddr *) &addr;
+ struct svc_serv *serv = svsk->sk_xprt.xpt_server;
+ struct socket *sock = svsk->sk_sock;
+ struct socket *newsock;
+ struct svc_sock *newsvsk;
+ int err, slen;
+
+ if (!sock)
+ return NULL;
+
+ clear_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
+ err = kernel_accept(sock, &newsock, O_NONBLOCK);
+ if (err < 0) {
+ if (err != -EAGAIN)
+ trace_svcsock_accept_err(xprt, serv->sv_name, err);
+ return NULL;
+ }
+ if (IS_ERR(sock_alloc_file(newsock, O_NONBLOCK, NULL)))
+ return NULL;
+
+ set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
+
+ err = kernel_getpeername(newsock, sin);
+ if (err < 0) {
+ trace_svcsock_getpeername_err(xprt, serv->sv_name, err);
+ goto failed; /* aborted connection or whatever */
+ }
+ slen = err;
+
+ /* Reset the inherited callbacks before calling svc_setup_socket */
+ newsock->sk->sk_state_change = svsk->sk_ostate;
+ newsock->sk->sk_data_ready = svsk->sk_odata;
+ newsock->sk->sk_write_space = svsk->sk_owspace;
+
+ /* make sure that a write doesn't block forever when
+ * low on memory
+ */
+ newsock->sk->sk_sndtimeo = HZ*30;
+
+ newsvsk = svc_setup_socket(serv, newsock,
+ (SVC_SOCK_ANONYMOUS | SVC_SOCK_TEMPORARY));
+ if (IS_ERR(newsvsk))
+ goto failed;
+ svc_xprt_set_remote(&newsvsk->sk_xprt, sin, slen);
+ err = kernel_getsockname(newsock, sin);
+ slen = err;
+ if (unlikely(err < 0))
+ slen = offsetof(struct sockaddr, sa_data);
+ svc_xprt_set_local(&newsvsk->sk_xprt, sin, slen);
+
+ if (sock_is_loopback(newsock->sk))
+ set_bit(XPT_LOCAL, &newsvsk->sk_xprt.xpt_flags);
+ else
+ clear_bit(XPT_LOCAL, &newsvsk->sk_xprt.xpt_flags);
+ if (serv->sv_stats)
+ serv->sv_stats->nettcpconn++;
+
+ return &newsvsk->sk_xprt;
+
+failed:
+ sockfd_put(newsock);
+ return NULL;
+}
+
+static size_t svc_tcp_restore_pages(struct svc_sock *svsk,
+ struct svc_rqst *rqstp)
+{
+ size_t len = svsk->sk_datalen;
+ unsigned int i, npages;
+
+ if (!len)
+ return 0;
+ npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ for (i = 0; i < npages; i++) {
+ if (rqstp->rq_pages[i] != NULL)
+ put_page(rqstp->rq_pages[i]);
+ BUG_ON(svsk->sk_pages[i] == NULL);
+ rqstp->rq_pages[i] = svsk->sk_pages[i];
+ svsk->sk_pages[i] = NULL;
+ }
+ rqstp->rq_arg.head[0].iov_base = page_address(rqstp->rq_pages[0]);
+ return len;
+}
+
+static void svc_tcp_save_pages(struct svc_sock *svsk, struct svc_rqst *rqstp)
+{
+ unsigned int i, len, npages;
+
+ if (svsk->sk_datalen == 0)
+ return;
+ len = svsk->sk_datalen;
+ npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ for (i = 0; i < npages; i++) {
+ svsk->sk_pages[i] = rqstp->rq_pages[i];
+ rqstp->rq_pages[i] = NULL;
+ }
+}
+
+static void svc_tcp_clear_pages(struct svc_sock *svsk)
+{
+ unsigned int i, len, npages;
+
+ if (svsk->sk_datalen == 0)
+ goto out;
+ len = svsk->sk_datalen;
+ npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ for (i = 0; i < npages; i++) {
+ if (svsk->sk_pages[i] == NULL) {
+ WARN_ON_ONCE(1);
+ continue;
+ }
+ put_page(svsk->sk_pages[i]);
+ svsk->sk_pages[i] = NULL;
+ }
+out:
+ svsk->sk_tcplen = 0;
+ svsk->sk_datalen = 0;
+}
+
+/*
+ * Receive fragment record header into sk_marker.
+ */
+static ssize_t svc_tcp_read_marker(struct svc_sock *svsk,
+ struct svc_rqst *rqstp)
+{
+ ssize_t want, len;
+
+ /* If we haven't gotten the record length yet,
+ * get the next four bytes.
+ */
+ if (svsk->sk_tcplen < sizeof(rpc_fraghdr)) {
+ struct msghdr msg = { NULL };
+ struct kvec iov;
+
+ want = sizeof(rpc_fraghdr) - svsk->sk_tcplen;
+ iov.iov_base = ((char *)&svsk->sk_marker) + svsk->sk_tcplen;
+ iov.iov_len = want;
+ iov_iter_kvec(&msg.msg_iter, ITER_DEST, &iov, 1, want);
+ len = svc_tcp_sock_recv_cmsg(svsk, &msg);
+ if (len < 0)
+ return len;
+ svsk->sk_tcplen += len;
+ if (len < want) {
+ /* call again to read the remaining bytes */
+ goto err_short;
+ }
+ trace_svcsock_marker(&svsk->sk_xprt, svsk->sk_marker);
+ if (svc_sock_reclen(svsk) + svsk->sk_datalen >
+ svsk->sk_xprt.xpt_server->sv_max_mesg)
+ goto err_too_large;
+ }
+ return svc_sock_reclen(svsk);
+
+err_too_large:
+ net_notice_ratelimited("svc: %s %s RPC fragment too large: %d\n",
+ __func__, svsk->sk_xprt.xpt_server->sv_name,
+ svc_sock_reclen(svsk));
+ svc_xprt_deferred_close(&svsk->sk_xprt);
+err_short:
+ return -EAGAIN;
+}
+
+static int receive_cb_reply(struct svc_sock *svsk, struct svc_rqst *rqstp)
+{
+ struct rpc_xprt *bc_xprt = svsk->sk_xprt.xpt_bc_xprt;
+ struct rpc_rqst *req = NULL;
+ struct kvec *src, *dst;
+ __be32 *p = (__be32 *)rqstp->rq_arg.head[0].iov_base;
+ __be32 xid;
+ __be32 calldir;
+
+ xid = *p++;
+ calldir = *p;
+
+ if (!bc_xprt)
+ return -EAGAIN;
+ spin_lock(&bc_xprt->queue_lock);
+ req = xprt_lookup_rqst(bc_xprt, xid);
+ if (!req)
+ goto unlock_notfound;
+
+ memcpy(&req->rq_private_buf, &req->rq_rcv_buf, sizeof(struct xdr_buf));
+ /*
+ * XXX!: cheating for now! Only copying HEAD.
+ * But we know this is good enough for now (in fact, for any
+ * callback reply in the forseeable future).
+ */
+ dst = &req->rq_private_buf.head[0];
+ src = &rqstp->rq_arg.head[0];
+ if (dst->iov_len < src->iov_len)
+ goto unlock_eagain; /* whatever; just giving up. */
+ memcpy(dst->iov_base, src->iov_base, src->iov_len);
+ xprt_complete_rqst(req->rq_task, rqstp->rq_arg.len);
+ rqstp->rq_arg.len = 0;
+ spin_unlock(&bc_xprt->queue_lock);
+ return 0;
+unlock_notfound:
+ printk(KERN_NOTICE
+ "%s: Got unrecognized reply: "
+ "calldir 0x%x xpt_bc_xprt %p xid %08x\n",
+ __func__, ntohl(calldir),
+ bc_xprt, ntohl(xid));
+unlock_eagain:
+ spin_unlock(&bc_xprt->queue_lock);
+ return -EAGAIN;
+}
+
+static void svc_tcp_fragment_received(struct svc_sock *svsk)
+{
+ /* If we have more data, signal svc_xprt_enqueue() to try again */
+ svsk->sk_tcplen = 0;
+ svsk->sk_marker = xdr_zero;
+
+ smp_wmb();
+ tcp_set_rcvlowat(svsk->sk_sk, 1);
+}
+
+/**
+ * svc_tcp_recvfrom - Receive data from a TCP socket
+ * @rqstp: request structure into which to receive an RPC Call
+ *
+ * Called in a loop when XPT_DATA has been set.
+ *
+ * Read the 4-byte stream record marker, then use the record length
+ * in that marker to set up exactly the resources needed to receive
+ * the next RPC message into @rqstp.
+ *
+ * Returns:
+ * On success, the number of bytes in a received RPC Call, or
+ * %0 if a complete RPC Call message was not ready to return
+ *
+ * The zero return case handles partial receives and callback Replies.
+ * The state of a partial receive is preserved in the svc_sock for
+ * the next call to svc_tcp_recvfrom.
+ */
+static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
+{
+ struct svc_sock *svsk =
+ container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
+ struct svc_serv *serv = svsk->sk_xprt.xpt_server;
+ size_t want, base;
+ ssize_t len;
+ __be32 *p;
+ __be32 calldir;
+
+ clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
+ len = svc_tcp_read_marker(svsk, rqstp);
+ if (len < 0)
+ goto error;
+
+ base = svc_tcp_restore_pages(svsk, rqstp);
+ want = len - (svsk->sk_tcplen - sizeof(rpc_fraghdr));
+ len = svc_tcp_read_msg(rqstp, base + want, base);
+ if (len >= 0) {
+ trace_svcsock_tcp_recv(&svsk->sk_xprt, len);
+ svsk->sk_tcplen += len;
+ svsk->sk_datalen += len;
+ }
+ if (len != want || !svc_sock_final_rec(svsk))
+ goto err_incomplete;
+ if (svsk->sk_datalen < 8)
+ goto err_nuts;
+
+ rqstp->rq_arg.len = svsk->sk_datalen;
+ rqstp->rq_arg.page_base = 0;
+ if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len) {
+ rqstp->rq_arg.head[0].iov_len = rqstp->rq_arg.len;
+ rqstp->rq_arg.page_len = 0;
+ } else
+ rqstp->rq_arg.page_len = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len;
+
+ rqstp->rq_xprt_ctxt = NULL;
+ rqstp->rq_prot = IPPROTO_TCP;
+ if (test_bit(XPT_LOCAL, &svsk->sk_xprt.xpt_flags))
+ set_bit(RQ_LOCAL, &rqstp->rq_flags);
+ else
+ clear_bit(RQ_LOCAL, &rqstp->rq_flags);
+
+ p = (__be32 *)rqstp->rq_arg.head[0].iov_base;
+ calldir = p[1];
+ if (calldir)
+ len = receive_cb_reply(svsk, rqstp);
+
+ /* Reset TCP read info */
+ svsk->sk_datalen = 0;
+ svc_tcp_fragment_received(svsk);
+
+ if (len < 0)
+ goto error;
+
+ svc_xprt_copy_addrs(rqstp, &svsk->sk_xprt);
+ if (serv->sv_stats)
+ serv->sv_stats->nettcpcnt++;
+
+ svc_sock_secure_port(rqstp);
+ svc_xprt_received(rqstp->rq_xprt);
+ return rqstp->rq_arg.len;
+
+err_incomplete:
+ svc_tcp_save_pages(svsk, rqstp);
+ if (len < 0 && len != -EAGAIN)
+ goto err_delete;
+ if (len == want)
+ svc_tcp_fragment_received(svsk);
+ else {
+ /* Avoid more ->sk_data_ready() calls until the rest
+ * of the message has arrived. This reduces service
+ * thread wake-ups on large incoming messages. */
+ tcp_set_rcvlowat(svsk->sk_sk,
+ svc_sock_reclen(svsk) - svsk->sk_tcplen);
+
+ trace_svcsock_tcp_recv_short(&svsk->sk_xprt,
+ svc_sock_reclen(svsk),
+ svsk->sk_tcplen - sizeof(rpc_fraghdr));
+ }
+ goto err_noclose;
+error:
+ if (len != -EAGAIN)
+ goto err_delete;
+ trace_svcsock_tcp_recv_eagain(&svsk->sk_xprt, 0);
+ goto err_noclose;
+err_nuts:
+ svsk->sk_datalen = 0;
+err_delete:
+ trace_svcsock_tcp_recv_err(&svsk->sk_xprt, len);
+ svc_xprt_deferred_close(&svsk->sk_xprt);
+err_noclose:
+ svc_xprt_received(rqstp->rq_xprt);
+ return 0; /* record not complete */
+}
+
+/*
+ * MSG_SPLICE_PAGES is used exclusively to reduce the number of
+ * copy operations in this path. Therefore the caller must ensure
+ * that the pages backing @xdr are unchanging.
+ *
+ * Note that the send is non-blocking. The caller has incremented
+ * the reference count on each page backing the RPC message, and
+ * the network layer will "put" these pages when transmission is
+ * complete.
+ *
+ * This is safe for our RPC services because the memory backing
+ * the head and tail components is never kmalloc'd. These always
+ * come from pages in the svc_rqst::rq_pages array.
+ */
+static int svc_tcp_sendmsg(struct svc_sock *svsk, struct svc_rqst *rqstp,
+ rpc_fraghdr marker, unsigned int *sentp)
+{
+ struct msghdr msg = {
+ .msg_flags = MSG_SPLICE_PAGES,
+ };
+ unsigned int count;
+ void *buf;
+ int ret;
+
+ *sentp = 0;
+
+ /* The stream record marker is copied into a temporary page
+ * fragment buffer so that it can be included in rq_bvec.
+ */
+ buf = page_frag_alloc(&svsk->sk_frag_cache, sizeof(marker),
+ GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+ memcpy(buf, &marker, sizeof(marker));
+ bvec_set_virt(rqstp->rq_bvec, buf, sizeof(marker));
+
+ count = xdr_buf_to_bvec(rqstp->rq_bvec + 1,
+ ARRAY_SIZE(rqstp->rq_bvec) - 1, &rqstp->rq_res);
+
+ iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, rqstp->rq_bvec,
+ 1 + count, sizeof(marker) + rqstp->rq_res.len);
+ ret = sock_sendmsg(svsk->sk_sock, &msg);
+ if (ret < 0)
+ return ret;
+ *sentp += ret;
+ return 0;
+}
+
+/**
+ * svc_tcp_sendto - Send out a reply on a TCP socket
+ * @rqstp: completed svc_rqst
+ *
+ * xpt_mutex ensures @rqstp's whole message is written to the socket
+ * without interruption.
+ *
+ * Returns the number of bytes sent, or a negative errno.
+ */
+static int svc_tcp_sendto(struct svc_rqst *rqstp)
+{
+ struct svc_xprt *xprt = rqstp->rq_xprt;
+ struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
+ struct xdr_buf *xdr = &rqstp->rq_res;
+ rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT |
+ (u32)xdr->len);
+ unsigned int sent;
+ int err;
+
+ svc_tcp_release_ctxt(xprt, rqstp->rq_xprt_ctxt);
+ rqstp->rq_xprt_ctxt = NULL;
+
+ mutex_lock(&xprt->xpt_mutex);
+ if (svc_xprt_is_dead(xprt))
+ goto out_notconn;
+ err = svc_tcp_sendmsg(svsk, rqstp, marker, &sent);
+ trace_svcsock_tcp_send(xprt, err < 0 ? (long)err : sent);
+ if (err < 0 || sent != (xdr->len + sizeof(marker)))
+ goto out_close;
+ mutex_unlock(&xprt->xpt_mutex);
+ return sent;
+
+out_notconn:
+ mutex_unlock(&xprt->xpt_mutex);
+ return -ENOTCONN;
+out_close:
+ pr_notice("rpc-srv/tcp: %s: %s %d when sending %d bytes - shutting down socket\n",
+ xprt->xpt_server->sv_name,
+ (err < 0) ? "got error" : "sent",
+ (err < 0) ? err : sent, xdr->len);
+ svc_xprt_deferred_close(xprt);
+ mutex_unlock(&xprt->xpt_mutex);
+ return -EAGAIN;
+}
+
+static struct svc_xprt *svc_tcp_create(struct svc_serv *serv,
+ struct net *net,
+ struct sockaddr *sa, int salen,
+ int flags)
+{
+ return svc_create_socket(serv, IPPROTO_TCP, net, sa, salen, flags);
+}
+
+static const struct svc_xprt_ops svc_tcp_ops = {
+ .xpo_create = svc_tcp_create,
+ .xpo_recvfrom = svc_tcp_recvfrom,
+ .xpo_sendto = svc_tcp_sendto,
+ .xpo_result_payload = svc_sock_result_payload,
+ .xpo_release_ctxt = svc_tcp_release_ctxt,
+ .xpo_detach = svc_tcp_sock_detach,
+ .xpo_free = svc_sock_free,
+ .xpo_has_wspace = svc_tcp_has_wspace,
+ .xpo_accept = svc_tcp_accept,
+ .xpo_kill_temp_xprt = svc_tcp_kill_temp_xprt,
+ .xpo_handshake = svc_tcp_handshake,
+};
+
+static struct svc_xprt_class svc_tcp_class = {
+ .xcl_name = "tcp",
+ .xcl_owner = THIS_MODULE,
+ .xcl_ops = &svc_tcp_ops,
+ .xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP,
+ .xcl_ident = XPRT_TRANSPORT_TCP,
+};
+
+void svc_init_xprt_sock(void)
+{
+ svc_reg_xprt_class(&svc_tcp_class);
+ svc_reg_xprt_class(&svc_udp_class);
+}
+
+void svc_cleanup_xprt_sock(void)
+{
+ svc_unreg_xprt_class(&svc_tcp_class);
+ svc_unreg_xprt_class(&svc_udp_class);
+}
+
+static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv)
+{
+ struct sock *sk = svsk->sk_sk;
+
+ svc_xprt_init(sock_net(svsk->sk_sock->sk), &svc_tcp_class,
+ &svsk->sk_xprt, serv);
+ set_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
+ set_bit(XPT_CONG_CTRL, &svsk->sk_xprt.xpt_flags);
+ if (sk->sk_state == TCP_LISTEN) {
+ strcpy(svsk->sk_xprt.xpt_remotebuf, "listener");
+ set_bit(XPT_LISTENER, &svsk->sk_xprt.xpt_flags);
+ sk->sk_data_ready = svc_tcp_listen_data_ready;
+ set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
+ } else {
+ sk->sk_state_change = svc_tcp_state_change;
+ sk->sk_data_ready = svc_data_ready;
+ sk->sk_write_space = svc_write_space;
+
+ svsk->sk_marker = xdr_zero;
+ svsk->sk_tcplen = 0;
+ svsk->sk_datalen = 0;
+ memset(&svsk->sk_pages[0], 0, sizeof(svsk->sk_pages));
+
+ tcp_sock_set_nodelay(sk);
+
+ set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
+ switch (sk->sk_state) {
+ case TCP_SYN_RECV:
+ case TCP_ESTABLISHED:
+ break;
+ default:
+ svc_xprt_deferred_close(&svsk->sk_xprt);
+ }
+ }
+}
+
+void svc_sock_update_bufs(struct svc_serv *serv)
+{
+ /*
+ * The number of server threads has changed. Update
+ * rcvbuf and sndbuf accordingly on all sockets
+ */
+ struct svc_sock *svsk;
+
+ spin_lock_bh(&serv->sv_lock);
+ list_for_each_entry(svsk, &serv->sv_permsocks, sk_xprt.xpt_list)
+ set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
+ spin_unlock_bh(&serv->sv_lock);
+}
+EXPORT_SYMBOL_GPL(svc_sock_update_bufs);
+
+/*
+ * Initialize socket for RPC use and create svc_sock struct
+ */
+static struct svc_sock *svc_setup_socket(struct svc_serv *serv,
+ struct socket *sock,
+ int flags)
+{
+ struct svc_sock *svsk;
+ struct sock *inet;
+ int pmap_register = !(flags & SVC_SOCK_ANONYMOUS);
+
+ svsk = kzalloc(sizeof(*svsk), GFP_KERNEL);
+ if (!svsk)
+ return ERR_PTR(-ENOMEM);
+
+ inet = sock->sk;
+
+ if (pmap_register) {
+ int err;
+
+ err = svc_register(serv, sock_net(sock->sk), inet->sk_family,
+ inet->sk_protocol,
+ ntohs(inet_sk(inet)->inet_sport));
+ if (err < 0) {
+ kfree(svsk);
+ return ERR_PTR(err);
+ }
+ }
+
+ svsk->sk_sock = sock;
+ svsk->sk_sk = inet;
+ svsk->sk_ostate = inet->sk_state_change;
+ svsk->sk_odata = inet->sk_data_ready;
+ svsk->sk_owspace = inet->sk_write_space;
+ /*
+ * This barrier is necessary in order to prevent race condition
+ * with svc_data_ready(), svc_tcp_listen_data_ready(), and others
+ * when calling callbacks above.
+ */
+ wmb();
+ inet->sk_user_data = svsk;
+
+ /* Initialize the socket */
+ if (sock->type == SOCK_DGRAM)
+ svc_udp_init(svsk, serv);
+ else
+ svc_tcp_init(svsk, serv);
+
+ trace_svcsock_new(svsk, sock);
+ return svsk;
+}
+
+/**
+ * svc_addsock - add a listener socket to an RPC service
+ * @serv: pointer to RPC service to which to add a new listener
+ * @net: caller's network namespace
+ * @fd: file descriptor of the new listener
+ * @name_return: pointer to buffer to fill in with name of listener
+ * @len: size of the buffer
+ * @cred: credential
+ *
+ * Fills in socket name and returns positive length of name if successful.
+ * Name is terminated with '\n'. On error, returns a negative errno
+ * value.
+ */
+int svc_addsock(struct svc_serv *serv, struct net *net, const int fd,
+ char *name_return, const size_t len, const struct cred *cred)
+{
+ int err = 0;
+ struct socket *so = sockfd_lookup(fd, &err);
+ struct svc_sock *svsk = NULL;
+ struct sockaddr_storage addr;
+ struct sockaddr *sin = (struct sockaddr *)&addr;
+ int salen;
+
+ if (!so)
+ return err;
+ err = -EINVAL;
+ if (sock_net(so->sk) != net)
+ goto out;
+ err = -EAFNOSUPPORT;
+ if ((so->sk->sk_family != PF_INET) && (so->sk->sk_family != PF_INET6))
+ goto out;
+ err = -EPROTONOSUPPORT;
+ if (so->sk->sk_protocol != IPPROTO_TCP &&
+ so->sk->sk_protocol != IPPROTO_UDP)
+ goto out;
+ err = -EISCONN;
+ if (so->state > SS_UNCONNECTED)
+ goto out;
+ err = -ENOENT;
+ if (!try_module_get(THIS_MODULE))
+ goto out;
+ svsk = svc_setup_socket(serv, so, SVC_SOCK_DEFAULTS);
+ if (IS_ERR(svsk)) {
+ module_put(THIS_MODULE);
+ err = PTR_ERR(svsk);
+ goto out;
+ }
+ salen = kernel_getsockname(svsk->sk_sock, sin);
+ if (salen >= 0)
+ svc_xprt_set_local(&svsk->sk_xprt, sin, salen);
+ svsk->sk_xprt.xpt_cred = get_cred(cred);
+ svc_add_new_perm_xprt(serv, &svsk->sk_xprt);
+ return svc_one_sock_name(svsk, name_return, len);
+out:
+ sockfd_put(so);
+ return err;
+}
+EXPORT_SYMBOL_GPL(svc_addsock);
+
+/*
+ * Create socket for RPC service.
+ */
+static struct svc_xprt *svc_create_socket(struct svc_serv *serv,
+ int protocol,
+ struct net *net,
+ struct sockaddr *sin, int len,
+ int flags)
+{
+ struct svc_sock *svsk;
+ struct socket *sock;
+ int error;
+ int type;
+ struct sockaddr_storage addr;
+ struct sockaddr *newsin = (struct sockaddr *)&addr;
+ int newlen;
+ int family;
+
+ if (protocol != IPPROTO_UDP && protocol != IPPROTO_TCP) {
+ printk(KERN_WARNING "svc: only UDP and TCP "
+ "sockets supported\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ type = (protocol == IPPROTO_UDP)? SOCK_DGRAM : SOCK_STREAM;
+ switch (sin->sa_family) {
+ case AF_INET6:
+ family = PF_INET6;
+ break;
+ case AF_INET:
+ family = PF_INET;
+ break;
+ default:
+ return ERR_PTR(-EINVAL);
+ }
+
+ error = __sock_create(net, family, type, protocol, &sock, 1);
+ if (error < 0)
+ return ERR_PTR(error);
+
+ svc_reclassify_socket(sock);
+
+ /*
+ * If this is an PF_INET6 listener, we want to avoid
+ * getting requests from IPv4 remotes. Those should
+ * be shunted to a PF_INET listener via rpcbind.
+ */
+ if (family == PF_INET6)
+ ip6_sock_set_v6only(sock->sk);
+ if (type == SOCK_STREAM)
+ sock->sk->sk_reuse = SK_CAN_REUSE; /* allow address reuse */
+ error = kernel_bind(sock, sin, len);
+ if (error < 0)
+ goto bummer;
+
+ error = kernel_getsockname(sock, newsin);
+ if (error < 0)
+ goto bummer;
+ newlen = error;
+
+ if (protocol == IPPROTO_TCP) {
+ if ((error = kernel_listen(sock, 64)) < 0)
+ goto bummer;
+ }
+
+ svsk = svc_setup_socket(serv, sock, flags);
+ if (IS_ERR(svsk)) {
+ error = PTR_ERR(svsk);
+ goto bummer;
+ }
+ svc_xprt_set_local(&svsk->sk_xprt, newsin, newlen);
+ return (struct svc_xprt *)svsk;
+bummer:
+ sock_release(sock);
+ return ERR_PTR(error);
+}
+
+/*
+ * Detach the svc_sock from the socket so that no
+ * more callbacks occur.
+ */
+static void svc_sock_detach(struct svc_xprt *xprt)
+{
+ struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
+ struct sock *sk = svsk->sk_sk;
+
+ /* put back the old socket callbacks */
+ lock_sock(sk);
+ sk->sk_state_change = svsk->sk_ostate;
+ sk->sk_data_ready = svsk->sk_odata;
+ sk->sk_write_space = svsk->sk_owspace;
+ sk->sk_user_data = NULL;
+ release_sock(sk);
+}
+
+/*
+ * Disconnect the socket, and reset the callbacks
+ */
+static void svc_tcp_sock_detach(struct svc_xprt *xprt)
+{
+ struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
+
+ tls_handshake_close(svsk->sk_sock);
+
+ svc_sock_detach(xprt);
+
+ if (!test_bit(XPT_LISTENER, &xprt->xpt_flags)) {
+ svc_tcp_clear_pages(svsk);
+ kernel_sock_shutdown(svsk->sk_sock, SHUT_RDWR);
+ }
+}
+
+/*
+ * Free the svc_sock's socket resources and the svc_sock itself.
+ */
+static void svc_sock_free(struct svc_xprt *xprt)
+{
+ struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
+ struct page_frag_cache *pfc = &svsk->sk_frag_cache;
+ struct socket *sock = svsk->sk_sock;
+
+ trace_svcsock_free(svsk, sock);
+
+ tls_handshake_cancel(sock->sk);
+ if (sock->file)
+ sockfd_put(sock);
+ else
+ sock_release(sock);
+ if (pfc->va)
+ __page_frag_cache_drain(virt_to_head_page(pfc->va),
+ pfc->pagecnt_bias);
+ kfree(svsk);
+}