1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/net/sunrpc/xprtsock.c
4 *
5 * Client-side transport implementation for sockets.
6 *
7 * TCP callback races fixes (C) 1998 Red Hat
8 * TCP send fixes (C) 1998 Red Hat
9 * TCP NFS related read + write fixes
10 *  (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
11 *
12 * Rewrite of larges part of the code in order to stabilize TCP stuff.
13 * Fix behaviour when socket buffer is full.
14 *  (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no>
15 *
16 * IP socket transport implementation, (C) 2005 Chuck Lever <cel@netapp.com>
17 *
18 * IPv6 support contributed by Gilles Quillard, Bull Open Source, 2005.
19 *   <gilles.quillard@bull.net>
20 */
21
22#include <linux/types.h>
23#include <linux/string.h>
24#include <linux/slab.h>
25#include <linux/module.h>
26#include <linux/capability.h>
27#include <linux/pagemap.h>
28#include <linux/errno.h>
29#include <linux/socket.h>
30#include <linux/in.h>
31#include <linux/net.h>
32#include <linux/mm.h>
33#include <linux/un.h>
34#include <linux/udp.h>
35#include <linux/tcp.h>
36#include <linux/sunrpc/clnt.h>
37#include <linux/sunrpc/addr.h>
38#include <linux/sunrpc/sched.h>
39#include <linux/sunrpc/svcsock.h>
40#include <linux/sunrpc/xprtsock.h>
41#include <linux/file.h>
42#ifdef CONFIG_SUNRPC_BACKCHANNEL
43#include <linux/sunrpc/bc_xprt.h>
44#endif
45
46#include <net/sock.h>
47#include <net/checksum.h>
48#include <net/udp.h>
49#include <net/tcp.h>
50#include <net/tls_prot.h>
51#include <net/handshake.h>
52
53#include <linux/bvec.h>
54#include <linux/highmem.h>
55#include <linux/uio.h>
56#include <linux/sched/mm.h>
57
58#include <trace/events/sock.h>
59#include <trace/events/sunrpc.h>
60
61#include "socklib.h"
62#include "sunrpc.h"
63
64static void xs_close(struct rpc_xprt *xprt);
65static void xs_reset_srcport(struct sock_xprt *transport);
66static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock);
67static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
68		struct socket *sock);
69
70/*
71 * xprtsock tunables
72 */
73static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
74static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
75static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
76
77static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
78static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
79
80#define XS_TCP_LINGER_TO	(15U * HZ)
81static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
82
83/*
84 * We can register our own files under /proc/sys/sunrpc by
85 * calling register_sysctl() again.  The files in that
86 * directory become the union of all files registered there.
87 *
88 * We simply need to make sure that we don't collide with
89 * someone else's file names!
90 */
91
92static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
93static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
94static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
95static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
96static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
97
98static struct ctl_table_header *sunrpc_table_header;
99
100static struct xprt_class xs_local_transport;
101static struct xprt_class xs_udp_transport;
102static struct xprt_class xs_tcp_transport;
103static struct xprt_class xs_tcp_tls_transport;
104static struct xprt_class xs_bc_tcp_transport;
105
106/*
107 * FIXME: changing the UDP slot table size should also resize the UDP
108 *        socket buffers for existing UDP transports
109 */
110static struct ctl_table xs_tunables_table[] = {
111	{
112		.procname	= "udp_slot_table_entries",
113		.data		= &xprt_udp_slot_table_entries,
114		.maxlen		= sizeof(unsigned int),
115		.mode		= 0644,
116		.proc_handler	= proc_dointvec_minmax,
117		.extra1		= &min_slot_table_size,
118		.extra2		= &max_slot_table_size
119	},
120	{
121		.procname	= "tcp_slot_table_entries",
122		.data		= &xprt_tcp_slot_table_entries,
123		.maxlen		= sizeof(unsigned int),
124		.mode		= 0644,
125		.proc_handler	= proc_dointvec_minmax,
126		.extra1		= &min_slot_table_size,
127		.extra2		= &max_slot_table_size
128	},
129	{
130		.procname	= "tcp_max_slot_table_entries",
131		.data		= &xprt_max_tcp_slot_table_entries,
132		.maxlen		= sizeof(unsigned int),
133		.mode		= 0644,
134		.proc_handler	= proc_dointvec_minmax,
135		.extra1		= &min_slot_table_size,
136		.extra2		= &max_tcp_slot_table_limit
137	},
138	{
139		.procname	= "min_resvport",
140		.data		= &xprt_min_resvport,
141		.maxlen		= sizeof(unsigned int),
142		.mode		= 0644,
143		.proc_handler	= proc_dointvec_minmax,
144		.extra1		= &xprt_min_resvport_limit,
145		.extra2		= &xprt_max_resvport_limit
146	},
147	{
148		.procname	= "max_resvport",
149		.data		= &xprt_max_resvport,
150		.maxlen		= sizeof(unsigned int),
151		.mode		= 0644,
152		.proc_handler	= proc_dointvec_minmax,
153		.extra1		= &xprt_min_resvport_limit,
154		.extra2		= &xprt_max_resvport_limit
155	},
156	{
157		.procname	= "tcp_fin_timeout",
158		.data		= &xs_tcp_fin_timeout,
159		.maxlen		= sizeof(xs_tcp_fin_timeout),
160		.mode		= 0644,
161		.proc_handler	= proc_dointvec_jiffies,
162	},
163};
164
165/*
166 * Wait duration for a reply from the RPC portmapper.
167 */
168#define XS_BIND_TO		(60U * HZ)
169
170/*
171 * Delay if a UDP socket connect error occurs.  This is most likely some
172 * kind of resource problem on the local host.
173 */
174#define XS_UDP_REEST_TO		(2U * HZ)
175
176/*
177 * The reestablish timeout allows clients to delay for a bit before attempting
178 * to reconnect to a server that just dropped our connection.
179 *
180 * We implement an exponential backoff when trying to reestablish a TCP
181 * transport connection with the server.  Some servers like to drop a TCP
182 * connection when they are overworked, so we start with a short timeout and
183 * increase over time if the server is down or not responding.
184 */
185#define XS_TCP_INIT_REEST_TO	(3U * HZ)
186
187/*
188 * TCP idle timeout; client drops the transport socket if it is idle
189 * for this long.  Note that we also timeout UDP sockets to prevent
190 * holding port numbers when there is no RPC traffic.
191 */
192#define XS_IDLE_DISC_TO		(5U * 60 * HZ)
193
194/*
195 * TLS handshake timeout.
196 */
197#define XS_TLS_HANDSHAKE_TO	(10U * HZ)
198
199#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
200# undef  RPC_DEBUG_DATA
201# define RPCDBG_FACILITY	RPCDBG_TRANS
202#endif
203
204#ifdef RPC_DEBUG_DATA
205static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
206{
207	u8 *buf = (u8 *) packet;
208	int j;
209
210	dprintk("RPC:       %s\n", msg);
211	for (j = 0; j < count && j < 128; j += 4) {
212		if (!(j & 31)) {
213			if (j)
214				dprintk("\n");
215			dprintk("0x%04x ", j);
216		}
217		dprintk("%02x%02x%02x%02x ",
218			buf[j], buf[j+1], buf[j+2], buf[j+3]);
219	}
220	dprintk("\n");
221}
222#else
223static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
224{
225	/* NOP */
226}
227#endif
228
229static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
230{
231	return (struct rpc_xprt *) sk->sk_user_data;
232}
233
234static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
235{
236	return (struct sockaddr *) &xprt->addr;
237}
238
239static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
240{
241	return (struct sockaddr_un *) &xprt->addr;
242}
243
244static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
245{
246	return (struct sockaddr_in *) &xprt->addr;
247}
248
249static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
250{
251	return (struct sockaddr_in6 *) &xprt->addr;
252}
253
254static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
255{
256	struct sockaddr *sap = xs_addr(xprt);
257	struct sockaddr_in6 *sin6;
258	struct sockaddr_in *sin;
259	struct sockaddr_un *sun;
260	char buf[128];
261
262	switch (sap->sa_family) {
263	case AF_LOCAL:
264		sun = xs_addr_un(xprt);
265		if (sun->sun_path[0]) {
266			strscpy(buf, sun->sun_path, sizeof(buf));
267		} else {
268			buf[0] = '@';
269			strscpy(buf+1, sun->sun_path+1, sizeof(buf)-1);
270		}
271		xprt->address_strings[RPC_DISPLAY_ADDR] =
272						kstrdup(buf, GFP_KERNEL);
273		break;
274	case AF_INET:
275		(void)rpc_ntop(sap, buf, sizeof(buf));
276		xprt->address_strings[RPC_DISPLAY_ADDR] =
277						kstrdup(buf, GFP_KERNEL);
278		sin = xs_addr_in(xprt);
279		snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
280		break;
281	case AF_INET6:
282		(void)rpc_ntop(sap, buf, sizeof(buf));
283		xprt->address_strings[RPC_DISPLAY_ADDR] =
284						kstrdup(buf, GFP_KERNEL);
285		sin6 = xs_addr_in6(xprt);
286		snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
287		break;
288	default:
289		BUG();
290	}
291
292	xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
293}
294
295static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
296{
297	struct sockaddr *sap = xs_addr(xprt);
298	char buf[128];
299
300	snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
301	xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
302
303	snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
304	xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
305}
306
307static void xs_format_peer_addresses(struct rpc_xprt *xprt,
308				     const char *protocol,
309				     const char *netid)
310{
311	xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
312	xprt->address_strings[RPC_DISPLAY_NETID] = netid;
313	xs_format_common_peer_addresses(xprt);
314	xs_format_common_peer_ports(xprt);
315}
316
317static void xs_update_peer_port(struct rpc_xprt *xprt)
318{
319	kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
320	kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
321
322	xs_format_common_peer_ports(xprt);
323}
324
325static void xs_free_peer_addresses(struct rpc_xprt *xprt)
326{
327	unsigned int i;
328
329	for (i = 0; i < RPC_DISPLAY_MAX; i++)
330		switch (i) {
331		case RPC_DISPLAY_PROTO:
332		case RPC_DISPLAY_NETID:
333			continue;
334		default:
335			kfree(xprt->address_strings[i]);
336		}
337}
338
339static size_t
340xs_alloc_sparse_pages(struct xdr_buf *buf, size_t want, gfp_t gfp)
341{
342	size_t i,n;
343
344	if (!want || !(buf->flags & XDRBUF_SPARSE_PAGES))
345		return want;
346	n = (buf->page_base + want + PAGE_SIZE - 1) >> PAGE_SHIFT;
347	for (i = 0; i < n; i++) {
348		if (buf->pages[i])
349			continue;
350		buf->bvec[i].bv_page = buf->pages[i] = alloc_page(gfp);
351		if (!buf->pages[i]) {
352			i *= PAGE_SIZE;
353			return i > buf->page_base ? i - buf->page_base : 0;
354		}
355	}
356	return want;
357}
358
359static int
360xs_sock_process_cmsg(struct socket *sock, struct msghdr *msg,
361		     struct cmsghdr *cmsg, int ret)
362{
363	u8 content_type = tls_get_record_type(sock->sk, cmsg);
364	u8 level, description;
365
366	switch (content_type) {
367	case 0:
368		break;
369	case TLS_RECORD_TYPE_DATA:
370		/* TLS sets EOR at the end of each application data
371		 * record, even though there might be more frames
372		 * waiting to be decrypted.
373		 */
374		msg->msg_flags &= ~MSG_EOR;
375		break;
376	case TLS_RECORD_TYPE_ALERT:
377		tls_alert_recv(sock->sk, msg, &level, &description);
378		ret = (level == TLS_ALERT_LEVEL_FATAL) ?
379			-EACCES : -EAGAIN;
380		break;
381	default:
382		/* discard this record type */
383		ret = -EAGAIN;
384	}
385	return ret;
386}
387
388static int
389xs_sock_recv_cmsg(struct socket *sock, struct msghdr *msg, int flags)
390{
391	union {
392		struct cmsghdr	cmsg;
393		u8		buf[CMSG_SPACE(sizeof(u8))];
394	} u;
395	int ret;
396
397	msg->msg_control = &u;
398	msg->msg_controllen = sizeof(u);
399	ret = sock_recvmsg(sock, msg, flags);
400	if (msg->msg_controllen != sizeof(u))
401		ret = xs_sock_process_cmsg(sock, msg, &u.cmsg, ret);
402	return ret;
403}
404
405static ssize_t
406xs_sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags, size_t seek)
407{
408	ssize_t ret;
409	if (seek != 0)
410		iov_iter_advance(&msg->msg_iter, seek);
411	ret = xs_sock_recv_cmsg(sock, msg, flags);
412	return ret > 0 ? ret + seek : ret;
413}
414
415static ssize_t
416xs_read_kvec(struct socket *sock, struct msghdr *msg, int flags,
417		struct kvec *kvec, size_t count, size_t seek)
418{
419	iov_iter_kvec(&msg->msg_iter, ITER_DEST, kvec, 1, count);
420	return xs_sock_recvmsg(sock, msg, flags, seek);
421}
422
423static ssize_t
424xs_read_bvec(struct socket *sock, struct msghdr *msg, int flags,
425		struct bio_vec *bvec, unsigned long nr, size_t count,
426		size_t seek)
427{
428	iov_iter_bvec(&msg->msg_iter, ITER_DEST, bvec, nr, count);
429	return xs_sock_recvmsg(sock, msg, flags, seek);
430}
431
432static ssize_t
433xs_read_discard(struct socket *sock, struct msghdr *msg, int flags,
434		size_t count)
435{
436	iov_iter_discard(&msg->msg_iter, ITER_DEST, count);
437	return xs_sock_recv_cmsg(sock, msg, flags);
438}
439
440#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
441static void
442xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
443{
444	struct bvec_iter bi = {
445		.bi_size = count,
446	};
447	struct bio_vec bv;
448
449	bvec_iter_advance(bvec, &bi, seek & PAGE_MASK);
450	for_each_bvec(bv, bvec, bi, bi)
451		flush_dcache_page(bv.bv_page);
452}
453#else
454static inline void
455xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
456{
457}
458#endif
459
460static ssize_t
461xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags,
462		struct xdr_buf *buf, size_t count, size_t seek, size_t *read)
463{
464	size_t want, seek_init = seek, offset = 0;
465	ssize_t ret;
466
467	want = min_t(size_t, count, buf->head[0].iov_len);
468	if (seek < want) {
469		ret = xs_read_kvec(sock, msg, flags, &buf->head[0], want, seek);
470		if (ret <= 0)
471			goto sock_err;
472		offset += ret;
473		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
474			goto out;
475		if (ret != want)
476			goto out;
477		seek = 0;
478	} else {
479		seek -= want;
480		offset += want;
481	}
482
483	want = xs_alloc_sparse_pages(
484		buf, min_t(size_t, count - offset, buf->page_len),
485		GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
486	if (seek < want) {
487		ret = xs_read_bvec(sock, msg, flags, buf->bvec,
488				xdr_buf_pagecount(buf),
489				want + buf->page_base,
490				seek + buf->page_base);
491		if (ret <= 0)
492			goto sock_err;
493		xs_flush_bvec(buf->bvec, ret, seek + buf->page_base);
494		ret -= buf->page_base;
495		offset += ret;
496		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
497			goto out;
498		if (ret != want)
499			goto out;
500		seek = 0;
501	} else {
502		seek -= want;
503		offset += want;
504	}
505
506	want = min_t(size_t, count - offset, buf->tail[0].iov_len);
507	if (seek < want) {
508		ret = xs_read_kvec(sock, msg, flags, &buf->tail[0], want, seek);
509		if (ret <= 0)
510			goto sock_err;
511		offset += ret;
512		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
513			goto out;
514		if (ret != want)
515			goto out;
516	} else if (offset < seek_init)
517		offset = seek_init;
518	ret = -EMSGSIZE;
519out:
520	*read = offset - seek_init;
521	return ret;
522sock_err:
523	offset += seek;
524	goto out;
525}
526
527static void
528xs_read_header(struct sock_xprt *transport, struct xdr_buf *buf)
529{
530	if (!transport->recv.copied) {
531		if (buf->head[0].iov_len >= transport->recv.offset)
532			memcpy(buf->head[0].iov_base,
533					&transport->recv.xid,
534					transport->recv.offset);
535		transport->recv.copied = transport->recv.offset;
536	}
537}
538
539static bool
540xs_read_stream_request_done(struct sock_xprt *transport)
541{
542	return transport->recv.fraghdr & cpu_to_be32(RPC_LAST_STREAM_FRAGMENT);
543}
544
545static void
546xs_read_stream_check_eor(struct sock_xprt *transport,
547		struct msghdr *msg)
548{
549	if (xs_read_stream_request_done(transport))
550		msg->msg_flags |= MSG_EOR;
551}
552
553static ssize_t
554xs_read_stream_request(struct sock_xprt *transport, struct msghdr *msg,
555		int flags, struct rpc_rqst *req)
556{
557	struct xdr_buf *buf = &req->rq_private_buf;
558	size_t want, read;
559	ssize_t ret;
560
561	xs_read_header(transport, buf);
562
563	want = transport->recv.len - transport->recv.offset;
564	if (want != 0) {
565		ret = xs_read_xdr_buf(transport->sock, msg, flags, buf,
566				transport->recv.copied + want,
567				transport->recv.copied,
568				&read);
569		transport->recv.offset += read;
570		transport->recv.copied += read;
571	}
572
573	if (transport->recv.offset == transport->recv.len)
574		xs_read_stream_check_eor(transport, msg);
575
576	if (want == 0)
577		return 0;
578
579	switch (ret) {
580	default:
581		break;
582	case -EFAULT:
583	case -EMSGSIZE:
584		msg->msg_flags |= MSG_TRUNC;
585		return read;
586	case 0:
587		return -ESHUTDOWN;
588	}
589	return ret < 0 ? ret : read;
590}
591
592static size_t
593xs_read_stream_headersize(bool isfrag)
594{
595	if (isfrag)
596		return sizeof(__be32);
597	return 3 * sizeof(__be32);
598}
599
600static ssize_t
601xs_read_stream_header(struct sock_xprt *transport, struct msghdr *msg,
602		int flags, size_t want, size_t seek)
603{
604	struct kvec kvec = {
605		.iov_base = &transport->recv.fraghdr,
606		.iov_len = want,
607	};
608	return xs_read_kvec(transport->sock, msg, flags, &kvec, want, seek);
609}
610
611#if defined(CONFIG_SUNRPC_BACKCHANNEL)
612static ssize_t
613xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
614{
615	struct rpc_xprt *xprt = &transport->xprt;
616	struct rpc_rqst *req;
617	ssize_t ret;
618
619	/* Is this transport associated with the backchannel? */
620	if (!xprt->bc_serv)
621		return -ESHUTDOWN;
622
623	/* Look up and lock the request corresponding to the given XID */
624	req = xprt_lookup_bc_request(xprt, transport->recv.xid);
625	if (!req) {
626		printk(KERN_WARNING "Callback slot table overflowed\n");
627		return -ESHUTDOWN;
628	}
629	if (transport->recv.copied && !req->rq_private_buf.len)
630		return -ESHUTDOWN;
631
632	ret = xs_read_stream_request(transport, msg, flags, req);
633	if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
634		xprt_complete_bc_request(req, transport->recv.copied);
635	else
636		req->rq_private_buf.len = transport->recv.copied;
637
638	return ret;
639}
640#else /* CONFIG_SUNRPC_BACKCHANNEL */
641static ssize_t
642xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
643{
644	return -ESHUTDOWN;
645}
646#endif /* CONFIG_SUNRPC_BACKCHANNEL */
647
648static ssize_t
649xs_read_stream_reply(struct sock_xprt *transport, struct msghdr *msg, int flags)
650{
651	struct rpc_xprt *xprt = &transport->xprt;
652	struct rpc_rqst *req;
653	ssize_t ret = 0;
654
655	/* Look up and lock the request corresponding to the given XID */
656	spin_lock(&xprt->queue_lock);
657	req = xprt_lookup_rqst(xprt, transport->recv.xid);
658	if (!req || (transport->recv.copied && !req->rq_private_buf.len)) {
659		msg->msg_flags |= MSG_TRUNC;
660		goto out;
661	}
662	xprt_pin_rqst(req);
663	spin_unlock(&xprt->queue_lock);
664
665	ret = xs_read_stream_request(transport, msg, flags, req);
666
667	spin_lock(&xprt->queue_lock);
668	if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
669		xprt_complete_rqst(req->rq_task, transport->recv.copied);
670	else
671		req->rq_private_buf.len = transport->recv.copied;
672	xprt_unpin_rqst(req);
673out:
674	spin_unlock(&xprt->queue_lock);
675	return ret;
676}
677
678static ssize_t
679xs_read_stream(struct sock_xprt *transport, int flags)
680{
681	struct msghdr msg = { 0 };
682	size_t want, read = 0;
683	ssize_t ret = 0;
684
685	if (transport->recv.len == 0) {
686		want = xs_read_stream_headersize(transport->recv.copied != 0);
687		ret = xs_read_stream_header(transport, &msg, flags, want,
688				transport->recv.offset);
689		if (ret <= 0)
690			goto out_err;
691		transport->recv.offset = ret;
692		if (transport->recv.offset != want)
693			return transport->recv.offset;
694		transport->recv.len = be32_to_cpu(transport->recv.fraghdr) &
695			RPC_FRAGMENT_SIZE_MASK;
696		transport->recv.offset -= sizeof(transport->recv.fraghdr);
697		read = ret;
698	}
699
700	switch (be32_to_cpu(transport->recv.calldir)) {
701	default:
702		msg.msg_flags |= MSG_TRUNC;
703		break;
704	case RPC_CALL:
705		ret = xs_read_stream_call(transport, &msg, flags);
706		break;
707	case RPC_REPLY:
708		ret = xs_read_stream_reply(transport, &msg, flags);
709	}
710	if (msg.msg_flags & MSG_TRUNC) {
711		transport->recv.calldir = cpu_to_be32(-1);
712		transport->recv.copied = -1;
713	}
714	if (ret < 0)
715		goto out_err;
716	read += ret;
717	if (transport->recv.offset < transport->recv.len) {
718		if (!(msg.msg_flags & MSG_TRUNC))
719			return read;
720		msg.msg_flags = 0;
721		ret = xs_read_discard(transport->sock, &msg, flags,
722				transport->recv.len - transport->recv.offset);
723		if (ret <= 0)
724			goto out_err;
725		transport->recv.offset += ret;
726		read += ret;
727		if (transport->recv.offset != transport->recv.len)
728			return read;
729	}
730	if (xs_read_stream_request_done(transport)) {
731		trace_xs_stream_read_request(transport);
732		transport->recv.copied = 0;
733	}
734	transport->recv.offset = 0;
735	transport->recv.len = 0;
736	return read;
737out_err:
738	return ret != 0 ? ret : -ESHUTDOWN;
739}
740
741static __poll_t xs_poll_socket(struct sock_xprt *transport)
742{
743	return transport->sock->ops->poll(transport->file, transport->sock,
744			NULL);
745}
746
747static bool xs_poll_socket_readable(struct sock_xprt *transport)
748{
749	__poll_t events = xs_poll_socket(transport);
750
751	return (events & (EPOLLIN | EPOLLRDNORM)) && !(events & EPOLLRDHUP);
752}
753
754static void xs_poll_check_readable(struct sock_xprt *transport)
755{
756
757	clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
758	if (test_bit(XPRT_SOCK_IGNORE_RECV, &transport->sock_state))
759		return;
760	if (!xs_poll_socket_readable(transport))
761		return;
762	if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
763		queue_work(xprtiod_workqueue, &transport->recv_worker);
764}
765
766static void xs_stream_data_receive(struct sock_xprt *transport)
767{
768	size_t read = 0;
769	ssize_t ret = 0;
770
771	mutex_lock(&transport->recv_mutex);
772	if (transport->sock == NULL)
773		goto out;
774	for (;;) {
775		ret = xs_read_stream(transport, MSG_DONTWAIT);
776		if (ret < 0)
777			break;
778		read += ret;
779		cond_resched();
780	}
781	if (ret == -ESHUTDOWN)
782		kernel_sock_shutdown(transport->sock, SHUT_RDWR);
783	else if (ret == -EACCES)
784		xprt_wake_pending_tasks(&transport->xprt, -EACCES);
785	else
786		xs_poll_check_readable(transport);
787out:
788	mutex_unlock(&transport->recv_mutex);
789	trace_xs_stream_read_data(&transport->xprt, ret, read);
790}
791
792static void xs_stream_data_receive_workfn(struct work_struct *work)
793{
794	struct sock_xprt *transport =
795		container_of(work, struct sock_xprt, recv_worker);
796	unsigned int pflags = memalloc_nofs_save();
797
798	xs_stream_data_receive(transport);
799	memalloc_nofs_restore(pflags);
800}
801
802static void
803xs_stream_reset_connect(struct sock_xprt *transport)
804{
805	transport->recv.offset = 0;
806	transport->recv.len = 0;
807	transport->recv.copied = 0;
808	transport->xmit.offset = 0;
809}
810
811static void
812xs_stream_start_connect(struct sock_xprt *transport)
813{
814	transport->xprt.stat.connect_count++;
815	transport->xprt.stat.connect_start = jiffies;
816}
817
818#define XS_SENDMSG_FLAGS	(MSG_DONTWAIT | MSG_NOSIGNAL)
819
820/**
821 * xs_nospace - handle transmit was incomplete
822 * @req: pointer to RPC request
823 * @transport: pointer to struct sock_xprt
824 *
825 */
826static int xs_nospace(struct rpc_rqst *req, struct sock_xprt *transport)
827{
828	struct rpc_xprt *xprt = &transport->xprt;
829	struct sock *sk = transport->inet;
830	int ret = -EAGAIN;
831
832	trace_rpc_socket_nospace(req, transport);
833
834	/* Protect against races with write_space */
835	spin_lock(&xprt->transport_lock);
836
837	/* Don't race with disconnect */
838	if (xprt_connected(xprt)) {
839		/* wait for more buffer space */
840		set_bit(XPRT_SOCK_NOSPACE, &transport->sock_state);
841		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
842		sk->sk_write_pending++;
843		xprt_wait_for_buffer_space(xprt);
844	} else
845		ret = -ENOTCONN;
846
847	spin_unlock(&xprt->transport_lock);
848	return ret;
849}
850
851static int xs_sock_nospace(struct rpc_rqst *req)
852{
853	struct sock_xprt *transport =
854		container_of(req->rq_xprt, struct sock_xprt, xprt);
855	struct sock *sk = transport->inet;
856	int ret = -EAGAIN;
857
858	lock_sock(sk);
859	if (!sock_writeable(sk))
860		ret = xs_nospace(req, transport);
861	release_sock(sk);
862	return ret;
863}
864
865static int xs_stream_nospace(struct rpc_rqst *req, bool vm_wait)
866{
867	struct sock_xprt *transport =
868		container_of(req->rq_xprt, struct sock_xprt, xprt);
869	struct sock *sk = transport->inet;
870	int ret = -EAGAIN;
871
872	if (vm_wait)
873		return -ENOBUFS;
874	lock_sock(sk);
875	if (!sk_stream_memory_free(sk))
876		ret = xs_nospace(req, transport);
877	release_sock(sk);
878	return ret;
879}
880
881static int xs_stream_prepare_request(struct rpc_rqst *req, struct xdr_buf *buf)
882{
883	return xdr_alloc_bvec(buf, rpc_task_gfp_mask());
884}
885
886static void xs_stream_abort_send_request(struct rpc_rqst *req)
887{
888	struct rpc_xprt *xprt = req->rq_xprt;
889	struct sock_xprt *transport =
890		container_of(xprt, struct sock_xprt, xprt);
891
892	if (transport->xmit.offset != 0 &&
893	    !test_bit(XPRT_CLOSE_WAIT, &xprt->state))
894		xprt_force_disconnect(xprt);
895}
896
897/*
898 * Determine if the previous message in the stream was aborted before it
899 * could complete transmission.
900 */
901static bool
902xs_send_request_was_aborted(struct sock_xprt *transport, struct rpc_rqst *req)
903{
904	return transport->xmit.offset != 0 && req->rq_bytes_sent == 0;
905}
906
907/*
908 * Return the stream record marker field for a record of length < 2^31-1
909 */
910static rpc_fraghdr
911xs_stream_record_marker(struct xdr_buf *xdr)
912{
913	if (!xdr->len)
914		return 0;
915	return cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | (u32)xdr->len);
916}
917
918/**
919 * xs_local_send_request - write an RPC request to an AF_LOCAL socket
920 * @req: pointer to RPC request
921 *
922 * Return values:
923 *        0:	The request has been sent
924 *   EAGAIN:	The socket was blocked, please call again later to
925 *		complete the request
926 * ENOTCONN:	Caller needs to invoke connect logic then call again
927 *    other:	Some other error occurred, the request was not sent
928 */
929static int xs_local_send_request(struct rpc_rqst *req)
930{
931	struct rpc_xprt *xprt = req->rq_xprt;
932	struct sock_xprt *transport =
933				container_of(xprt, struct sock_xprt, xprt);
934	struct xdr_buf *xdr = &req->rq_snd_buf;
935	rpc_fraghdr rm = xs_stream_record_marker(xdr);
936	unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
937	struct msghdr msg = {
938		.msg_flags	= XS_SENDMSG_FLAGS,
939	};
940	bool vm_wait;
941	unsigned int sent;
942	int status;
943
944	/* Close the stream if the previous transmission was incomplete */
945	if (xs_send_request_was_aborted(transport, req)) {
946		xprt_force_disconnect(xprt);
947		return -ENOTCONN;
948	}
949
950	xs_pktdump("packet data:",
951			req->rq_svec->iov_base, req->rq_svec->iov_len);
952
953	vm_wait = sk_stream_is_writeable(transport->inet) ? true : false;
954
955	req->rq_xtime = ktime_get();
956	status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
957				   transport->xmit.offset, rm, &sent);
958	dprintk("RPC:       %s(%u) = %d\n",
959			__func__, xdr->len - transport->xmit.offset, status);
960
961	if (likely(sent > 0) || status == 0) {
962		transport->xmit.offset += sent;
963		req->rq_bytes_sent = transport->xmit.offset;
964		if (likely(req->rq_bytes_sent >= msglen)) {
965			req->rq_xmit_bytes_sent += transport->xmit.offset;
966			transport->xmit.offset = 0;
967			return 0;
968		}
969		status = -EAGAIN;
970		vm_wait = false;
971	}
972
973	switch (status) {
974	case -EAGAIN:
975		status = xs_stream_nospace(req, vm_wait);
976		break;
977	default:
978		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
979			-status);
980		fallthrough;
981	case -EPIPE:
982		xprt_force_disconnect(xprt);
983		status = -ENOTCONN;
984	}
985
986	return status;
987}
988
989/**
990 * xs_udp_send_request - write an RPC request to a UDP socket
991 * @req: pointer to RPC request
992 *
993 * Return values:
994 *        0:	The request has been sent
995 *   EAGAIN:	The socket was blocked, please call again later to
996 *		complete the request
997 * ENOTCONN:	Caller needs to invoke connect logic then call again
998 *    other:	Some other error occurred, the request was not sent
999 */
1000static int xs_udp_send_request(struct rpc_rqst *req)
1001{
1002	struct rpc_xprt *xprt = req->rq_xprt;
1003	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1004	struct xdr_buf *xdr = &req->rq_snd_buf;
1005	struct msghdr msg = {
1006		.msg_name	= xs_addr(xprt),
1007		.msg_namelen	= xprt->addrlen,
1008		.msg_flags	= XS_SENDMSG_FLAGS,
1009	};
1010	unsigned int sent;
1011	int status;
1012
1013	xs_pktdump("packet data:",
1014				req->rq_svec->iov_base,
1015				req->rq_svec->iov_len);
1016
1017	if (!xprt_bound(xprt))
1018		return -ENOTCONN;
1019
1020	if (!xprt_request_get_cong(xprt, req))
1021		return -EBADSLT;
1022
1023	status = xdr_alloc_bvec(xdr, rpc_task_gfp_mask());
1024	if (status < 0)
1025		return status;
1026	req->rq_xtime = ktime_get();
1027	status = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, 0, &sent);
1028
1029	dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
1030			xdr->len, status);
1031
1032	/* firewall is blocking us, don't return -EAGAIN or we end up looping */
1033	if (status == -EPERM)
1034		goto process_status;
1035
1036	if (status == -EAGAIN && sock_writeable(transport->inet))
1037		status = -ENOBUFS;
1038
1039	if (sent > 0 || status == 0) {
1040		req->rq_xmit_bytes_sent += sent;
1041		if (sent >= req->rq_slen)
1042			return 0;
1043		/* Still some bytes left; set up for a retry later. */
1044		status = -EAGAIN;
1045	}
1046
1047process_status:
1048	switch (status) {
1049	case -ENOTSOCK:
1050		status = -ENOTCONN;
1051		/* Should we call xs_close() here? */
1052		break;
1053	case -EAGAIN:
1054		status = xs_sock_nospace(req);
1055		break;
1056	case -ENETUNREACH:
1057	case -ENOBUFS:
1058	case -EPIPE:
1059	case -ECONNREFUSED:
1060	case -EPERM:
1061		/* When the server has died, an ICMP port unreachable message
1062		 * prompts ECONNREFUSED. */
1063		break;
1064	default:
1065		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1066			-status);
1067	}
1068
1069	return status;
1070}
1071
1072/**
1073 * xs_tcp_send_request - write an RPC request to a TCP socket
1074 * @req: pointer to RPC request
1075 *
1076 * Return values:
1077 *        0:	The request has been sent
1078 *   EAGAIN:	The socket was blocked, please call again later to
1079 *		complete the request
1080 * ENOTCONN:	Caller needs to invoke connect logic then call again
1081 *    other:	Some other error occurred, the request was not sent
1082 *
1083 * XXX: In the case of soft timeouts, should we eventually give up
1084 *	if sendmsg is not able to make progress?
1085 */
1086static int xs_tcp_send_request(struct rpc_rqst *req)
1087{
1088	struct rpc_xprt *xprt = req->rq_xprt;
1089	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1090	struct xdr_buf *xdr = &req->rq_snd_buf;
1091	rpc_fraghdr rm = xs_stream_record_marker(xdr);
1092	unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
1093	struct msghdr msg = {
1094		.msg_flags	= XS_SENDMSG_FLAGS,
1095	};
1096	bool vm_wait;
1097	unsigned int sent;
1098	int status;
1099
1100	/* Close the stream if the previous transmission was incomplete */
1101	if (xs_send_request_was_aborted(transport, req)) {
1102		if (transport->sock != NULL)
1103			kernel_sock_shutdown(transport->sock, SHUT_RDWR);
1104		return -ENOTCONN;
1105	}
1106	if (!transport->inet)
1107		return -ENOTCONN;
1108
1109	xs_pktdump("packet data:",
1110				req->rq_svec->iov_base,
1111				req->rq_svec->iov_len);
1112
1113	if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state))
1114		xs_tcp_set_socket_timeouts(xprt, transport->sock);
1115
1116	xs_set_srcport(transport, transport->sock);
1117
1118	/* Continue transmitting the packet/record. We must be careful
1119	 * to cope with writespace callbacks arriving _after_ we have
1120	 * called sendmsg(). */
1121	req->rq_xtime = ktime_get();
1122	tcp_sock_set_cork(transport->inet, true);
1123
1124	vm_wait = sk_stream_is_writeable(transport->inet) ? true : false;
1125
1126	do {
1127		status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
1128					   transport->xmit.offset, rm, &sent);
1129
1130		dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
1131				xdr->len - transport->xmit.offset, status);
1132
1133		/* If we've sent the entire packet, immediately
1134		 * reset the count of bytes sent. */
1135		transport->xmit.offset += sent;
1136		req->rq_bytes_sent = transport->xmit.offset;
1137		if (likely(req->rq_bytes_sent >= msglen)) {
1138			req->rq_xmit_bytes_sent += transport->xmit.offset;
1139			transport->xmit.offset = 0;
1140			if (atomic_long_read(&xprt->xmit_queuelen) == 1)
1141				tcp_sock_set_cork(transport->inet, false);
1142			return 0;
1143		}
1144
1145		WARN_ON_ONCE(sent == 0 && status == 0);
1146
1147		if (sent > 0)
1148			vm_wait = false;
1149
1150	} while (status == 0);
1151
1152	switch (status) {
1153	case -ENOTSOCK:
1154		status = -ENOTCONN;
1155		/* Should we call xs_close() here? */
1156		break;
1157	case -EAGAIN:
1158		status = xs_stream_nospace(req, vm_wait);
1159		break;
1160	case -ECONNRESET:
1161	case -ECONNREFUSED:
1162	case -ENOTCONN:
1163	case -EADDRINUSE:
1164	case -ENOBUFS:
1165	case -EPIPE:
1166		break;
1167	default:
1168		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1169			-status);
1170	}
1171
1172	return status;
1173}
1174
1175static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1176{
1177	transport->old_data_ready = sk->sk_data_ready;
1178	transport->old_state_change = sk->sk_state_change;
1179	transport->old_write_space = sk->sk_write_space;
1180	transport->old_error_report = sk->sk_error_report;
1181}
1182
1183static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1184{
1185	sk->sk_data_ready = transport->old_data_ready;
1186	sk->sk_state_change = transport->old_state_change;
1187	sk->sk_write_space = transport->old_write_space;
1188	sk->sk_error_report = transport->old_error_report;
1189}
1190
1191static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
1192{
1193	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1194
1195	transport->xprt_err = 0;
1196	clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1197	clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state);
1198	clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state);
1199	clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state);
1200	clear_bit(XPRT_SOCK_NOSPACE, &transport->sock_state);
1201}
1202
1203static void xs_run_error_worker(struct sock_xprt *transport, unsigned int nr)
1204{
1205	set_bit(nr, &transport->sock_state);
1206	queue_work(xprtiod_workqueue, &transport->error_worker);
1207}
1208
1209static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
1210{
1211	xprt->connect_cookie++;
1212	smp_mb__before_atomic();
1213	clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1214	clear_bit(XPRT_CLOSING, &xprt->state);
1215	xs_sock_reset_state_flags(xprt);
1216	smp_mb__after_atomic();
1217}
1218
1219/**
1220 * xs_error_report - callback to handle TCP socket state errors
1221 * @sk: socket
1222 *
1223 * Note: we don't call sock_error() since there may be a rpc_task
1224 * using the socket, and so we don't want to clear sk->sk_err.
1225 */
1226static void xs_error_report(struct sock *sk)
1227{
1228	struct sock_xprt *transport;
1229	struct rpc_xprt *xprt;
1230
1231	if (!(xprt = xprt_from_sock(sk)))
1232		return;
1233
1234	transport = container_of(xprt, struct sock_xprt, xprt);
1235	transport->xprt_err = -sk->sk_err;
1236	if (transport->xprt_err == 0)
1237		return;
1238	dprintk("RPC:       xs_error_report client %p, error=%d...\n",
1239			xprt, -transport->xprt_err);
1240	trace_rpc_socket_error(xprt, sk->sk_socket, transport->xprt_err);
1241
1242	/* barrier ensures xprt_err is set before XPRT_SOCK_WAKE_ERROR */
1243	smp_mb__before_atomic();
1244	xs_run_error_worker(transport, XPRT_SOCK_WAKE_ERROR);
1245}
1246
1247static void xs_reset_transport(struct sock_xprt *transport)
1248{
1249	struct socket *sock = transport->sock;
1250	struct sock *sk = transport->inet;
1251	struct rpc_xprt *xprt = &transport->xprt;
1252	struct file *filp = transport->file;
1253
1254	if (sk == NULL)
1255		return;
1256	/*
1257	 * Make sure we're calling this in a context from which it is safe
1258	 * to call __fput_sync(). In practice that means rpciod and the
1259	 * system workqueue.
1260	 */
1261	if (!(current->flags & PF_WQ_WORKER)) {
1262		WARN_ON_ONCE(1);
1263		set_bit(XPRT_CLOSE_WAIT, &xprt->state);
1264		return;
1265	}
1266
1267	if (atomic_read(&transport->xprt.swapper))
1268		sk_clear_memalloc(sk);
1269
1270	tls_handshake_cancel(sk);
1271
1272	kernel_sock_shutdown(sock, SHUT_RDWR);
1273
1274	mutex_lock(&transport->recv_mutex);
1275	lock_sock(sk);
1276	transport->inet = NULL;
1277	transport->sock = NULL;
1278	transport->file = NULL;
1279
1280	sk->sk_user_data = NULL;
1281
1282	xs_restore_old_callbacks(transport, sk);
1283	xprt_clear_connected(xprt);
1284	xs_sock_reset_connection_flags(xprt);
1285	/* Reset stream record info */
1286	xs_stream_reset_connect(transport);
1287	release_sock(sk);
1288	mutex_unlock(&transport->recv_mutex);
1289
1290	trace_rpc_socket_close(xprt, sock);
1291	__fput_sync(filp);
1292
1293	xprt_disconnect_done(xprt);
1294}
1295
1296/**
1297 * xs_close - close a socket
1298 * @xprt: transport
1299 *
1300 * This is used when all requests are complete; ie, no DRC state remains
1301 * on the server we want to save.
1302 *
1303 * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
1304 * xs_reset_transport() zeroing the socket from underneath a writer.
1305 */
1306static void xs_close(struct rpc_xprt *xprt)
1307{
1308	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1309
1310	dprintk("RPC:       xs_close xprt %p\n", xprt);
1311
1312	if (transport->sock)
1313		tls_handshake_close(transport->sock);
1314	xs_reset_transport(transport);
1315	xprt->reestablish_timeout = 0;
1316}
1317
1318static void xs_inject_disconnect(struct rpc_xprt *xprt)
1319{
1320	dprintk("RPC:       injecting transport disconnect on xprt=%p\n",
1321		xprt);
1322	xprt_disconnect_done(xprt);
1323}
1324
1325static void xs_xprt_free(struct rpc_xprt *xprt)
1326{
1327	xs_free_peer_addresses(xprt);
1328	xprt_free(xprt);
1329}
1330
1331/**
1332 * xs_destroy - prepare to shutdown a transport
1333 * @xprt: doomed transport
1334 *
1335 */
1336static void xs_destroy(struct rpc_xprt *xprt)
1337{
1338	struct sock_xprt *transport = container_of(xprt,
1339			struct sock_xprt, xprt);
1340	dprintk("RPC:       xs_destroy xprt %p\n", xprt);
1341
1342	cancel_delayed_work_sync(&transport->connect_worker);
1343	xs_close(xprt);
1344	cancel_work_sync(&transport->recv_worker);
1345	cancel_work_sync(&transport->error_worker);
1346	xs_xprt_free(xprt);
1347	module_put(THIS_MODULE);
1348}
1349
1350/**
1351 * xs_udp_data_read_skb - receive callback for UDP sockets
1352 * @xprt: transport
1353 * @sk: socket
1354 * @skb: skbuff
1355 *
1356 */
1357static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
1358		struct sock *sk,
1359		struct sk_buff *skb)
1360{
1361	struct rpc_task *task;
1362	struct rpc_rqst *rovr;
1363	int repsize, copied;
1364	u32 _xid;
1365	__be32 *xp;
1366
1367	repsize = skb->len;
1368	if (repsize < 4) {
1369		dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
1370		return;
1371	}
1372
1373	/* Copy the XID from the skb... */
1374	xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
1375	if (xp == NULL)
1376		return;
1377
1378	/* Look up and lock the request corresponding to the given XID */
1379	spin_lock(&xprt->queue_lock);
1380	rovr = xprt_lookup_rqst(xprt, *xp);
1381	if (!rovr)
1382		goto out_unlock;
1383	xprt_pin_rqst(rovr);
1384	xprt_update_rtt(rovr->rq_task);
1385	spin_unlock(&xprt->queue_lock);
1386	task = rovr->rq_task;
1387
1388	if ((copied = rovr->rq_private_buf.buflen) > repsize)
1389		copied = repsize;
1390
1391	/* Suck it into the iovec, verify checksum if not done by hw. */
1392	if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1393		spin_lock(&xprt->queue_lock);
1394		__UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
1395		goto out_unpin;
1396	}
1397
1398
1399	spin_lock(&xprt->transport_lock);
1400	xprt_adjust_cwnd(xprt, task, copied);
1401	spin_unlock(&xprt->transport_lock);
1402	spin_lock(&xprt->queue_lock);
1403	xprt_complete_rqst(task, copied);
1404	__UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
1405out_unpin:
1406	xprt_unpin_rqst(rovr);
1407 out_unlock:
1408	spin_unlock(&xprt->queue_lock);
1409}
1410
1411static void xs_udp_data_receive(struct sock_xprt *transport)
1412{
1413	struct sk_buff *skb;
1414	struct sock *sk;
1415	int err;
1416
1417	mutex_lock(&transport->recv_mutex);
1418	sk = transport->inet;
1419	if (sk == NULL)
1420		goto out;
1421	for (;;) {
1422		skb = skb_recv_udp(sk, MSG_DONTWAIT, &err);
1423		if (skb == NULL)
1424			break;
1425		xs_udp_data_read_skb(&transport->xprt, sk, skb);
1426		consume_skb(skb);
1427		cond_resched();
1428	}
1429	xs_poll_check_readable(transport);
1430out:
1431	mutex_unlock(&transport->recv_mutex);
1432}
1433
1434static void xs_udp_data_receive_workfn(struct work_struct *work)
1435{
1436	struct sock_xprt *transport =
1437		container_of(work, struct sock_xprt, recv_worker);
1438	unsigned int pflags = memalloc_nofs_save();
1439
1440	xs_udp_data_receive(transport);
1441	memalloc_nofs_restore(pflags);
1442}
1443
1444/**
1445 * xs_data_ready - "data ready" callback for sockets
1446 * @sk: socket with data to read
1447 *
1448 */
1449static void xs_data_ready(struct sock *sk)
1450{
1451	struct rpc_xprt *xprt;
1452
1453	trace_sk_data_ready(sk);
1454
1455	xprt = xprt_from_sock(sk);
1456	if (xprt != NULL) {
1457		struct sock_xprt *transport = container_of(xprt,
1458				struct sock_xprt, xprt);
1459
1460		trace_xs_data_ready(xprt);
1461
1462		transport->old_data_ready(sk);
1463
1464		if (test_bit(XPRT_SOCK_IGNORE_RECV, &transport->sock_state))
1465			return;
1466
1467		/* Any data means we had a useful conversation, so
1468		 * then we don't need to delay the next reconnect
1469		 */
1470		if (xprt->reestablish_timeout)
1471			xprt->reestablish_timeout = 0;
1472		if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1473			queue_work(xprtiod_workqueue, &transport->recv_worker);
1474	}
1475}
1476
1477/*
1478 * Helper function to force a TCP close if the server is sending
1479 * junk and/or it has put us in CLOSE_WAIT
1480 */
1481static void xs_tcp_force_close(struct rpc_xprt *xprt)
1482{
1483	xprt_force_disconnect(xprt);
1484}
1485
1486#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1487static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
1488{
1489	return PAGE_SIZE;
1490}
1491#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1492
1493/**
1494 * xs_local_state_change - callback to handle AF_LOCAL socket state changes
1495 * @sk: socket whose state has changed
1496 *
1497 */
1498static void xs_local_state_change(struct sock *sk)
1499{
1500	struct rpc_xprt *xprt;
1501	struct sock_xprt *transport;
1502
1503	if (!(xprt = xprt_from_sock(sk)))
1504		return;
1505	transport = container_of(xprt, struct sock_xprt, xprt);
1506	if (sk->sk_shutdown & SHUTDOWN_MASK) {
1507		clear_bit(XPRT_CONNECTED, &xprt->state);
1508		/* Trigger the socket release */
1509		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1510	}
1511}
1512
1513/**
1514 * xs_tcp_state_change - callback to handle TCP socket state changes
1515 * @sk: socket whose state has changed
1516 *
1517 */
1518static void xs_tcp_state_change(struct sock *sk)
1519{
1520	struct rpc_xprt *xprt;
1521	struct sock_xprt *transport;
1522
1523	if (!(xprt = xprt_from_sock(sk)))
1524		return;
1525	dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1526	dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1527			sk->sk_state, xprt_connected(xprt),
1528			sock_flag(sk, SOCK_DEAD),
1529			sock_flag(sk, SOCK_ZAPPED),
1530			sk->sk_shutdown);
1531
1532	transport = container_of(xprt, struct sock_xprt, xprt);
1533	trace_rpc_socket_state_change(xprt, sk->sk_socket);
1534	switch (sk->sk_state) {
1535	case TCP_ESTABLISHED:
1536		if (!xprt_test_and_set_connected(xprt)) {
1537			xprt->connect_cookie++;
1538			clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
1539			xprt_clear_connecting(xprt);
1540
1541			xprt->stat.connect_count++;
1542			xprt->stat.connect_time += (long)jiffies -
1543						   xprt->stat.connect_start;
1544			xs_run_error_worker(transport, XPRT_SOCK_WAKE_PENDING);
1545		}
1546		break;
1547	case TCP_FIN_WAIT1:
1548		/* The client initiated a shutdown of the socket */
1549		xprt->connect_cookie++;
1550		xprt->reestablish_timeout = 0;
1551		set_bit(XPRT_CLOSING, &xprt->state);
1552		smp_mb__before_atomic();
1553		clear_bit(XPRT_CONNECTED, &xprt->state);
1554		clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1555		smp_mb__after_atomic();
1556		break;
1557	case TCP_CLOSE_WAIT:
1558		/* The server initiated a shutdown of the socket */
1559		xprt->connect_cookie++;
1560		clear_bit(XPRT_CONNECTED, &xprt->state);
1561		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1562		fallthrough;
1563	case TCP_CLOSING:
1564		/*
1565		 * If the server closed down the connection, make sure that
1566		 * we back off before reconnecting
1567		 */
1568		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1569			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1570		break;
1571	case TCP_LAST_ACK:
1572		set_bit(XPRT_CLOSING, &xprt->state);
1573		smp_mb__before_atomic();
1574		clear_bit(XPRT_CONNECTED, &xprt->state);
1575		smp_mb__after_atomic();
1576		break;
1577	case TCP_CLOSE:
1578		if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
1579				       &transport->sock_state)) {
1580			xs_reset_srcport(transport);
1581			xprt_clear_connecting(xprt);
1582		}
1583		clear_bit(XPRT_CLOSING, &xprt->state);
1584		/* Trigger the socket release */
1585		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1586	}
1587}
1588
1589static void xs_write_space(struct sock *sk)
1590{
1591	struct sock_xprt *transport;
1592	struct rpc_xprt *xprt;
1593
1594	if (!sk->sk_socket)
1595		return;
1596	clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1597
1598	if (unlikely(!(xprt = xprt_from_sock(sk))))
1599		return;
1600	transport = container_of(xprt, struct sock_xprt, xprt);
1601	if (!test_and_clear_bit(XPRT_SOCK_NOSPACE, &transport->sock_state))
1602		return;
1603	xs_run_error_worker(transport, XPRT_SOCK_WAKE_WRITE);
1604	sk->sk_write_pending--;
1605}
1606
1607/**
1608 * xs_udp_write_space - callback invoked when socket buffer space
1609 *                             becomes available
1610 * @sk: socket whose state has changed
1611 *
1612 * Called when more output buffer space is available for this socket.
1613 * We try not to wake our writers until they can make "significant"
1614 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1615 * with a bunch of small requests.
1616 */
1617static void xs_udp_write_space(struct sock *sk)
1618{
1619	/* from net/core/sock.c:sock_def_write_space */
1620	if (sock_writeable(sk))
1621		xs_write_space(sk);
1622}
1623
1624/**
1625 * xs_tcp_write_space - callback invoked when socket buffer space
1626 *                             becomes available
1627 * @sk: socket whose state has changed
1628 *
1629 * Called when more output buffer space is available for this socket.
1630 * We try not to wake our writers until they can make "significant"
1631 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1632 * with a bunch of small requests.
1633 */
1634static void xs_tcp_write_space(struct sock *sk)
1635{
1636	/* from net/core/stream.c:sk_stream_write_space */
1637	if (sk_stream_is_writeable(sk))
1638		xs_write_space(sk);
1639}
1640
1641static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1642{
1643	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1644	struct sock *sk = transport->inet;
1645
1646	if (transport->rcvsize) {
1647		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1648		sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1649	}
1650	if (transport->sndsize) {
1651		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1652		sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1653		sk->sk_write_space(sk);
1654	}
1655}
1656
1657/**
1658 * xs_udp_set_buffer_size - set send and receive limits
1659 * @xprt: generic transport
1660 * @sndsize: requested size of send buffer, in bytes
1661 * @rcvsize: requested size of receive buffer, in bytes
1662 *
1663 * Set socket send and receive buffer size limits.
1664 */
1665static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1666{
1667	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1668
1669	transport->sndsize = 0;
1670	if (sndsize)
1671		transport->sndsize = sndsize + 1024;
1672	transport->rcvsize = 0;
1673	if (rcvsize)
1674		transport->rcvsize = rcvsize + 1024;
1675
1676	xs_udp_do_set_buffer_size(xprt);
1677}
1678
1679/**
1680 * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1681 * @xprt: controlling transport
1682 * @task: task that timed out
1683 *
1684 * Adjust the congestion window after a retransmit timeout has occurred.
1685 */
1686static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1687{
1688	spin_lock(&xprt->transport_lock);
1689	xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1690	spin_unlock(&xprt->transport_lock);
1691}
1692
1693static int xs_get_random_port(void)
1694{
1695	unsigned short min = xprt_min_resvport, max = xprt_max_resvport;
1696	unsigned short range;
1697	unsigned short rand;
1698
1699	if (max < min)
1700		return -EADDRINUSE;
1701	range = max - min + 1;
1702	rand = get_random_u32_below(range);
1703	return rand + min;
1704}
1705
1706static unsigned short xs_sock_getport(struct socket *sock)
1707{
1708	struct sockaddr_storage buf;
1709	unsigned short port = 0;
1710
1711	if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0)
1712		goto out;
1713	switch (buf.ss_family) {
1714	case AF_INET6:
1715		port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1716		break;
1717	case AF_INET:
1718		port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1719	}
1720out:
1721	return port;
1722}
1723
1724/**
1725 * xs_set_port - reset the port number in the remote endpoint address
1726 * @xprt: generic transport
1727 * @port: new port number
1728 *
1729 */
1730static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1731{
1732	dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1733
1734	rpc_set_port(xs_addr(xprt), port);
1735	xs_update_peer_port(xprt);
1736}
1737
1738static void xs_reset_srcport(struct sock_xprt *transport)
1739{
1740	transport->srcport = 0;
1741}
1742
1743static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1744{
1745	if (transport->srcport == 0 && transport->xprt.reuseport)
1746		transport->srcport = xs_sock_getport(sock);
1747}
1748
1749static int xs_get_srcport(struct sock_xprt *transport)
1750{
1751	int port = transport->srcport;
1752
1753	if (port == 0 && transport->xprt.resvport)
1754		port = xs_get_random_port();
1755	return port;
1756}
1757
1758static unsigned short xs_sock_srcport(struct rpc_xprt *xprt)
1759{
1760	struct sock_xprt *sock = container_of(xprt, struct sock_xprt, xprt);
1761	unsigned short ret = 0;
1762	mutex_lock(&sock->recv_mutex);
1763	if (sock->sock)
1764		ret = xs_sock_getport(sock->sock);
1765	mutex_unlock(&sock->recv_mutex);
1766	return ret;
1767}
1768
1769static int xs_sock_srcaddr(struct rpc_xprt *xprt, char *buf, size_t buflen)
1770{
1771	struct sock_xprt *sock = container_of(xprt, struct sock_xprt, xprt);
1772	union {
1773		struct sockaddr sa;
1774		struct sockaddr_storage st;
1775	} saddr;
1776	int ret = -ENOTCONN;
1777
1778	mutex_lock(&sock->recv_mutex);
1779	if (sock->sock) {
1780		ret = kernel_getsockname(sock->sock, &saddr.sa);
1781		if (ret >= 0)
1782			ret = snprintf(buf, buflen, "%pISc", &saddr.sa);
1783	}
1784	mutex_unlock(&sock->recv_mutex);
1785	return ret;
1786}
1787
1788static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1789{
1790	if (transport->srcport != 0)
1791		transport->srcport = 0;
1792	if (!transport->xprt.resvport)
1793		return 0;
1794	if (port <= xprt_min_resvport || port > xprt_max_resvport)
1795		return xprt_max_resvport;
1796	return --port;
1797}
1798static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1799{
1800	struct sockaddr_storage myaddr;
1801	int err, nloop = 0;
1802	int port = xs_get_srcport(transport);
1803	unsigned short last;
1804
1805	/*
1806	 * If we are asking for any ephemeral port (i.e. port == 0 &&
1807	 * transport->xprt.resvport == 0), don't bind.  Let the local
1808	 * port selection happen implicitly when the socket is used
1809	 * (for example at connect time).
1810	 *
1811	 * This ensures that we can continue to establish TCP
1812	 * connections even when all local ephemeral ports are already
1813	 * a part of some TCP connection.  This makes no difference
1814	 * for UDP sockets, but also doesn't harm them.
1815	 *
1816	 * If we're asking for any reserved port (i.e. port == 0 &&
1817	 * transport->xprt.resvport == 1) xs_get_srcport above will
1818	 * ensure that port is non-zero and we will bind as needed.
1819	 */
1820	if (port <= 0)
1821		return port;
1822
1823	memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1824	do {
1825		rpc_set_port((struct sockaddr *)&myaddr, port);
1826		err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1827				transport->xprt.addrlen);
1828		if (err == 0) {
1829			if (transport->xprt.reuseport)
1830				transport->srcport = port;
1831			break;
1832		}
1833		last = port;
1834		port = xs_next_srcport(transport, port);
1835		if (port > last)
1836			nloop++;
1837	} while (err == -EADDRINUSE && nloop != 2);
1838
1839	if (myaddr.ss_family == AF_INET)
1840		dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1841				&((struct sockaddr_in *)&myaddr)->sin_addr,
1842				port, err ? "failed" : "ok", err);
1843	else
1844		dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1845				&((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1846				port, err ? "failed" : "ok", err);
1847	return err;
1848}
1849
1850/*
1851 * We don't support autobind on AF_LOCAL sockets
1852 */
1853static void xs_local_rpcbind(struct rpc_task *task)
1854{
1855	xprt_set_bound(task->tk_xprt);
1856}
1857
1858static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1859{
1860}
1861
1862#ifdef CONFIG_DEBUG_LOCK_ALLOC
1863static struct lock_class_key xs_key[3];
1864static struct lock_class_key xs_slock_key[3];
1865
1866static inline void xs_reclassify_socketu(struct socket *sock)
1867{
1868	struct sock *sk = sock->sk;
1869
1870	sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1871		&xs_slock_key[0], "sk_lock-AF_LOCAL-RPC", &xs_key[0]);
1872}
1873
1874static inline void xs_reclassify_socket4(struct socket *sock)
1875{
1876	struct sock *sk = sock->sk;
1877
1878	sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1879		&xs_slock_key[1], "sk_lock-AF_INET-RPC", &xs_key[1]);
1880}
1881
1882static inline void xs_reclassify_socket6(struct socket *sock)
1883{
1884	struct sock *sk = sock->sk;
1885
1886	sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1887		&xs_slock_key[2], "sk_lock-AF_INET6-RPC", &xs_key[2]);
1888}
1889
1890static inline void xs_reclassify_socket(int family, struct socket *sock)
1891{
1892	if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
1893		return;
1894
1895	switch (family) {
1896	case AF_LOCAL:
1897		xs_reclassify_socketu(sock);
1898		break;
1899	case AF_INET:
1900		xs_reclassify_socket4(sock);
1901		break;
1902	case AF_INET6:
1903		xs_reclassify_socket6(sock);
1904		break;
1905	}
1906}
1907#else
1908static inline void xs_reclassify_socket(int family, struct socket *sock)
1909{
1910}
1911#endif
1912
1913static void xs_dummy_setup_socket(struct work_struct *work)
1914{
1915}
1916
1917static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1918		struct sock_xprt *transport, int family, int type,
1919		int protocol, bool reuseport)
1920{
1921	struct file *filp;
1922	struct socket *sock;
1923	int err;
1924
1925	err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1926	if (err < 0) {
1927		dprintk("RPC:       can't create %d transport socket (%d).\n",
1928				protocol, -err);
1929		goto out;
1930	}
1931	xs_reclassify_socket(family, sock);
1932
1933	if (reuseport)
1934		sock_set_reuseport(sock->sk);
1935
1936	err = xs_bind(transport, sock);
1937	if (err) {
1938		sock_release(sock);
1939		goto out;
1940	}
1941
1942	filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1943	if (IS_ERR(filp))
1944		return ERR_CAST(filp);
1945	transport->file = filp;
1946
1947	return sock;
1948out:
1949	return ERR_PTR(err);
1950}
1951
1952static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1953				      struct socket *sock)
1954{
1955	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1956									xprt);
1957
1958	if (!transport->inet) {
1959		struct sock *sk = sock->sk;
1960
1961		lock_sock(sk);
1962
1963		xs_save_old_callbacks(transport, sk);
1964
1965		sk->sk_user_data = xprt;
1966		sk->sk_data_ready = xs_data_ready;
1967		sk->sk_write_space = xs_udp_write_space;
1968		sk->sk_state_change = xs_local_state_change;
1969		sk->sk_error_report = xs_error_report;
1970		sk->sk_use_task_frag = false;
1971
1972		xprt_clear_connected(xprt);
1973
1974		/* Reset to new socket */
1975		transport->sock = sock;
1976		transport->inet = sk;
1977
1978		release_sock(sk);
1979	}
1980
1981	xs_stream_start_connect(transport);
1982
1983	return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1984}
1985
1986/**
1987 * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1988 * @transport: socket transport to connect
1989 */
1990static int xs_local_setup_socket(struct sock_xprt *transport)
1991{
1992	struct rpc_xprt *xprt = &transport->xprt;
1993	struct file *filp;
1994	struct socket *sock;
1995	int status;
1996
1997	status = __sock_create(xprt->xprt_net, AF_LOCAL,
1998					SOCK_STREAM, 0, &sock, 1);
1999	if (status < 0) {
2000		dprintk("RPC:       can't create AF_LOCAL "
2001			"transport socket (%d).\n", -status);
2002		goto out;
2003	}
2004	xs_reclassify_socket(AF_LOCAL, sock);
2005
2006	filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
2007	if (IS_ERR(filp)) {
2008		status = PTR_ERR(filp);
2009		goto out;
2010	}
2011	transport->file = filp;
2012
2013	dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
2014			xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2015
2016	status = xs_local_finish_connecting(xprt, sock);
2017	trace_rpc_socket_connect(xprt, sock, status);
2018	switch (status) {
2019	case 0:
2020		dprintk("RPC:       xprt %p connected to %s\n",
2021				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2022		xprt->stat.connect_count++;
2023		xprt->stat.connect_time += (long)jiffies -
2024					   xprt->stat.connect_start;
2025		xprt_set_connected(xprt);
2026		break;
2027	case -ENOBUFS:
2028		break;
2029	case -ENOENT:
2030		dprintk("RPC:       xprt %p: socket %s does not exist\n",
2031				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2032		break;
2033	case -ECONNREFUSED:
2034		dprintk("RPC:       xprt %p: connection refused for %s\n",
2035				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2036		break;
2037	default:
2038		printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
2039				__func__, -status,
2040				xprt->address_strings[RPC_DISPLAY_ADDR]);
2041	}
2042
2043out:
2044	xprt_clear_connecting(xprt);
2045	xprt_wake_pending_tasks(xprt, status);
2046	return status;
2047}
2048
2049static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2050{
2051	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2052	int ret;
2053
2054	if (transport->file)
2055		goto force_disconnect;
2056
2057	if (RPC_IS_ASYNC(task)) {
2058		/*
2059		 * We want the AF_LOCAL connect to be resolved in the
2060		 * filesystem namespace of the process making the rpc
2061		 * call.  Thus we connect synchronously.
2062		 *
2063		 * If we want to support asynchronous AF_LOCAL calls,
2064		 * we'll need to figure out how to pass a namespace to
2065		 * connect.
2066		 */
2067		rpc_task_set_rpc_status(task, -ENOTCONN);
2068		goto out_wake;
2069	}
2070	ret = xs_local_setup_socket(transport);
2071	if (ret && !RPC_IS_SOFTCONN(task))
2072		msleep_interruptible(15000);
2073	return;
2074force_disconnect:
2075	xprt_force_disconnect(xprt);
2076out_wake:
2077	xprt_clear_connecting(xprt);
2078	xprt_wake_pending_tasks(xprt, -ENOTCONN);
2079}
2080
2081#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
2082/*
2083 * Note that this should be called with XPRT_LOCKED held, or recv_mutex
2084 * held, or when we otherwise know that we have exclusive access to the
2085 * socket, to guard against races with xs_reset_transport.
2086 */
2087static void xs_set_memalloc(struct rpc_xprt *xprt)
2088{
2089	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
2090			xprt);
2091
2092	/*
2093	 * If there's no sock, then we have nothing to set. The
2094	 * reconnecting process will get it for us.
2095	 */
2096	if (!transport->inet)
2097		return;
2098	if (atomic_read(&xprt->swapper))
2099		sk_set_memalloc(transport->inet);
2100}
2101
2102/**
2103 * xs_enable_swap - Tag this transport as being used for swap.
2104 * @xprt: transport to tag
2105 *
2106 * Take a reference to this transport on behalf of the rpc_clnt, and
2107 * optionally mark it for swapping if it wasn't already.
2108 */
2109static int
2110xs_enable_swap(struct rpc_xprt *xprt)
2111{
2112	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2113
2114	mutex_lock(&xs->recv_mutex);
2115	if (atomic_inc_return(&xprt->swapper) == 1 &&
2116	    xs->inet)
2117		sk_set_memalloc(xs->inet);
2118	mutex_unlock(&xs->recv_mutex);
2119	return 0;
2120}
2121
2122/**
2123 * xs_disable_swap - Untag this transport as being used for swap.
2124 * @xprt: transport to tag
2125 *
2126 * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
2127 * swapper refcount goes to 0, untag the socket as a memalloc socket.
2128 */
2129static void
2130xs_disable_swap(struct rpc_xprt *xprt)
2131{
2132	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2133
2134	mutex_lock(&xs->recv_mutex);
2135	if (atomic_dec_and_test(&xprt->swapper) &&
2136	    xs->inet)
2137		sk_clear_memalloc(xs->inet);
2138	mutex_unlock(&xs->recv_mutex);
2139}
2140#else
2141static void xs_set_memalloc(struct rpc_xprt *xprt)
2142{
2143}
2144
2145static int
2146xs_enable_swap(struct rpc_xprt *xprt)
2147{
2148	return -EINVAL;
2149}
2150
2151static void
2152xs_disable_swap(struct rpc_xprt *xprt)
2153{
2154}
2155#endif
2156
2157static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2158{
2159	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2160
2161	if (!transport->inet) {
2162		struct sock *sk = sock->sk;
2163
2164		lock_sock(sk);
2165
2166		xs_save_old_callbacks(transport, sk);
2167
2168		sk->sk_user_data = xprt;
2169		sk->sk_data_ready = xs_data_ready;
2170		sk->sk_write_space = xs_udp_write_space;
2171		sk->sk_use_task_frag = false;
2172
2173		xprt_set_connected(xprt);
2174
2175		/* Reset to new socket */
2176		transport->sock = sock;
2177		transport->inet = sk;
2178
2179		xs_set_memalloc(xprt);
2180
2181		release_sock(sk);
2182	}
2183	xs_udp_do_set_buffer_size(xprt);
2184
2185	xprt->stat.connect_start = jiffies;
2186}
2187
2188static void xs_udp_setup_socket(struct work_struct *work)
2189{
2190	struct sock_xprt *transport =
2191		container_of(work, struct sock_xprt, connect_worker.work);
2192	struct rpc_xprt *xprt = &transport->xprt;
2193	struct socket *sock;
2194	int status = -EIO;
2195	unsigned int pflags = current->flags;
2196
2197	if (atomic_read(&xprt->swapper))
2198		current->flags |= PF_MEMALLOC;
2199	sock = xs_create_sock(xprt, transport,
2200			xs_addr(xprt)->sa_family, SOCK_DGRAM,
2201			IPPROTO_UDP, false);
2202	if (IS_ERR(sock))
2203		goto out;
2204
2205	dprintk("RPC:       worker connecting xprt %p via %s to "
2206				"%s (port %s)\n", xprt,
2207			xprt->address_strings[RPC_DISPLAY_PROTO],
2208			xprt->address_strings[RPC_DISPLAY_ADDR],
2209			xprt->address_strings[RPC_DISPLAY_PORT]);
2210
2211	xs_udp_finish_connecting(xprt, sock);
2212	trace_rpc_socket_connect(xprt, sock, 0);
2213	status = 0;
2214out:
2215	xprt_clear_connecting(xprt);
2216	xprt_unlock_connect(xprt, transport);
2217	xprt_wake_pending_tasks(xprt, status);
2218	current_restore_flags(pflags, PF_MEMALLOC);
2219}
2220
2221/**
2222 * xs_tcp_shutdown - gracefully shut down a TCP socket
2223 * @xprt: transport
2224 *
2225 * Initiates a graceful shutdown of the TCP socket by calling the
2226 * equivalent of shutdown(SHUT_RDWR);
2227 */
2228static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2229{
2230	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2231	struct socket *sock = transport->sock;
2232	int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
2233
2234	if (sock == NULL)
2235		return;
2236	if (!xprt->reuseport) {
2237		xs_close(xprt);
2238		return;
2239	}
2240	switch (skst) {
2241	case TCP_FIN_WAIT1:
2242	case TCP_FIN_WAIT2:
2243	case TCP_LAST_ACK:
2244		break;
2245	case TCP_ESTABLISHED:
2246	case TCP_CLOSE_WAIT:
2247		kernel_sock_shutdown(sock, SHUT_RDWR);
2248		trace_rpc_socket_shutdown(xprt, sock);
2249		break;
2250	default:
2251		xs_reset_transport(transport);
2252	}
2253}
2254
2255static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
2256		struct socket *sock)
2257{
2258	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2259	struct net *net = sock_net(sock->sk);
2260	unsigned long connect_timeout;
2261	unsigned long syn_retries;
2262	unsigned int keepidle;
2263	unsigned int keepcnt;
2264	unsigned int timeo;
2265	unsigned long t;
2266
2267	spin_lock(&xprt->transport_lock);
2268	keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
2269	keepcnt = xprt->timeout->to_retries + 1;
2270	timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2271		(xprt->timeout->to_retries + 1);
2272	clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2273	spin_unlock(&xprt->transport_lock);
2274
2275	/* TCP Keepalive options */
2276	sock_set_keepalive(sock->sk);
2277	tcp_sock_set_keepidle(sock->sk, keepidle);
2278	tcp_sock_set_keepintvl(sock->sk, keepidle);
2279	tcp_sock_set_keepcnt(sock->sk, keepcnt);
2280
2281	/* TCP user timeout (see RFC5482) */
2282	tcp_sock_set_user_timeout(sock->sk, timeo);
2283
2284	/* Connect timeout */
2285	connect_timeout = max_t(unsigned long,
2286				DIV_ROUND_UP(xprt->connect_timeout, HZ), 1);
2287	syn_retries = max_t(unsigned long,
2288			    READ_ONCE(net->ipv4.sysctl_tcp_syn_retries), 1);
2289	for (t = 0; t <= syn_retries && (1UL << t) < connect_timeout; t++)
2290		;
2291	if (t <= syn_retries)
2292		tcp_sock_set_syncnt(sock->sk, t - 1);
2293}
2294
2295static void xs_tcp_do_set_connect_timeout(struct rpc_xprt *xprt,
2296					  unsigned long connect_timeout)
2297{
2298	struct sock_xprt *transport =
2299		container_of(xprt, struct sock_xprt, xprt);
2300	struct rpc_timeout to;
2301	unsigned long initval;
2302
2303	memcpy(&to, xprt->timeout, sizeof(to));
2304	/* Arbitrary lower limit */
2305	initval = max_t(unsigned long, connect_timeout, XS_TCP_INIT_REEST_TO);
2306	to.to_initval = initval;
2307	to.to_maxval = initval;
2308	to.to_retries = 0;
2309	memcpy(&transport->tcp_timeout, &to, sizeof(transport->tcp_timeout));
2310	xprt->timeout = &transport->tcp_timeout;
2311	xprt->connect_timeout = connect_timeout;
2312}
2313
2314static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
2315		unsigned long connect_timeout,
2316		unsigned long reconnect_timeout)
2317{
2318	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2319
2320	spin_lock(&xprt->transport_lock);
2321	if (reconnect_timeout < xprt->max_reconnect_timeout)
2322		xprt->max_reconnect_timeout = reconnect_timeout;
2323	if (connect_timeout < xprt->connect_timeout)
2324		xs_tcp_do_set_connect_timeout(xprt, connect_timeout);
2325	set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2326	spin_unlock(&xprt->transport_lock);
2327}
2328
2329static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2330{
2331	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2332
2333	if (!transport->inet) {
2334		struct sock *sk = sock->sk;
2335
2336		/* Avoid temporary address, they are bad for long-lived
2337		 * connections such as NFS mounts.
2338		 * RFC4941, section 3.6 suggests that:
2339		 *    Individual applications, which have specific
2340		 *    knowledge about the normal duration of connections,
2341		 *    MAY override this as appropriate.
2342		 */
2343		if (xs_addr(xprt)->sa_family == PF_INET6) {
2344			ip6_sock_set_addr_preferences(sk,
2345				IPV6_PREFER_SRC_PUBLIC);
2346		}
2347
2348		xs_tcp_set_socket_timeouts(xprt, sock);
2349		tcp_sock_set_nodelay(sk);
2350
2351		lock_sock(sk);
2352
2353		xs_save_old_callbacks(transport, sk);
2354
2355		sk->sk_user_data = xprt;
2356		sk->sk_data_ready = xs_data_ready;
2357		sk->sk_state_change = xs_tcp_state_change;
2358		sk->sk_write_space = xs_tcp_write_space;
2359		sk->sk_error_report = xs_error_report;
2360		sk->sk_use_task_frag = false;
2361
2362		/* socket options */
2363		sock_reset_flag(sk, SOCK_LINGER);
2364
2365		xprt_clear_connected(xprt);
2366
2367		/* Reset to new socket */
2368		transport->sock = sock;
2369		transport->inet = sk;
2370
2371		release_sock(sk);
2372	}
2373
2374	if (!xprt_bound(xprt))
2375		return -ENOTCONN;
2376
2377	xs_set_memalloc(xprt);
2378
2379	xs_stream_start_connect(transport);
2380
2381	/* Tell the socket layer to start connecting... */
2382	set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2383	return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2384}
2385
2386/**
2387 * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2388 * @work: queued work item
2389 *
2390 * Invoked by a work queue tasklet.
2391 */
2392static void xs_tcp_setup_socket(struct work_struct *work)
2393{
2394	struct sock_xprt *transport =
2395		container_of(work, struct sock_xprt, connect_worker.work);
2396	struct socket *sock = transport->sock;
2397	struct rpc_xprt *xprt = &transport->xprt;
2398	int status;
2399	unsigned int pflags = current->flags;
2400
2401	if (atomic_read(&xprt->swapper))
2402		current->flags |= PF_MEMALLOC;
2403
2404	if (xprt_connected(xprt))
2405		goto out;
2406	if (test_and_clear_bit(XPRT_SOCK_CONNECT_SENT,
2407			       &transport->sock_state) ||
2408	    !sock) {
2409		xs_reset_transport(transport);
2410		sock = xs_create_sock(xprt, transport, xs_addr(xprt)->sa_family,
2411				      SOCK_STREAM, IPPROTO_TCP, true);
2412		if (IS_ERR(sock)) {
2413			xprt_wake_pending_tasks(xprt, PTR_ERR(sock));
2414			goto out;
2415		}
2416	}
2417
2418	dprintk("RPC:       worker connecting xprt %p via %s to "
2419				"%s (port %s)\n", xprt,
2420			xprt->address_strings[RPC_DISPLAY_PROTO],
2421			xprt->address_strings[RPC_DISPLAY_ADDR],
2422			xprt->address_strings[RPC_DISPLAY_PORT]);
2423
2424	status = xs_tcp_finish_connecting(xprt, sock);
2425	trace_rpc_socket_connect(xprt, sock, status);
2426	dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2427			xprt, -status, xprt_connected(xprt),
2428			sock->sk->sk_state);
2429	switch (status) {
2430	case 0:
2431	case -EINPROGRESS:
2432		/* SYN_SENT! */
2433		set_bit(XPRT_SOCK_CONNECT_SENT, &transport->sock_state);
2434		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2435			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2436		fallthrough;
2437	case -EALREADY:
2438		goto out_unlock;
2439	case -EADDRNOTAVAIL:
2440		/* Source port number is unavailable. Try a new one! */
2441		transport->srcport = 0;
2442		status = -EAGAIN;
2443		break;
2444	case -EINVAL:
2445		/* Happens, for instance, if the user specified a link
2446		 * local IPv6 address without a scope-id.
2447		 */
2448	case -ECONNREFUSED:
2449	case -ECONNRESET:
2450	case -ENETDOWN:
2451	case -ENETUNREACH:
2452	case -EHOSTUNREACH:
2453	case -EADDRINUSE:
2454	case -ENOBUFS:
2455		break;
2456	default:
2457		printk("%s: connect returned unhandled error %d\n",
2458			__func__, status);
2459		status = -EAGAIN;
2460	}
2461
2462	/* xs_tcp_force_close() wakes tasks with a fixed error code.
2463	 * We need to wake them first to ensure the correct error code.
2464	 */
2465	xprt_wake_pending_tasks(xprt, status);
2466	xs_tcp_force_close(xprt);
2467out:
2468	xprt_clear_connecting(xprt);
2469out_unlock:
2470	xprt_unlock_connect(xprt, transport);
2471	current_restore_flags(pflags, PF_MEMALLOC);
2472}
2473
2474/*
2475 * Transfer the connected socket to @upper_transport, then mark that
2476 * xprt CONNECTED.
2477 */
2478static int xs_tcp_tls_finish_connecting(struct rpc_xprt *lower_xprt,
2479					struct sock_xprt *upper_transport)
2480{
2481	struct sock_xprt *lower_transport =
2482			container_of(lower_xprt, struct sock_xprt, xprt);
2483	struct rpc_xprt *upper_xprt = &upper_transport->xprt;
2484
2485	if (!upper_transport->inet) {
2486		struct socket *sock = lower_transport->sock;
2487		struct sock *sk = sock->sk;
2488
2489		/* Avoid temporary address, they are bad for long-lived
2490		 * connections such as NFS mounts.
2491		 * RFC4941, section 3.6 suggests that:
2492		 *    Individual applications, which have specific
2493		 *    knowledge about the normal duration of connections,
2494		 *    MAY override this as appropriate.
2495		 */
2496		if (xs_addr(upper_xprt)->sa_family == PF_INET6)
2497			ip6_sock_set_addr_preferences(sk, IPV6_PREFER_SRC_PUBLIC);
2498
2499		xs_tcp_set_socket_timeouts(upper_xprt, sock);
2500		tcp_sock_set_nodelay(sk);
2501
2502		lock_sock(sk);
2503
2504		/* @sk is already connected, so it now has the RPC callbacks.
2505		 * Reach into @lower_transport to save the original ones.
2506		 */
2507		upper_transport->old_data_ready = lower_transport->old_data_ready;
2508		upper_transport->old_state_change = lower_transport->old_state_change;
2509		upper_transport->old_write_space = lower_transport->old_write_space;
2510		upper_transport->old_error_report = lower_transport->old_error_report;
2511		sk->sk_user_data = upper_xprt;
2512
2513		/* socket options */
2514		sock_reset_flag(sk, SOCK_LINGER);
2515
2516		xprt_clear_connected(upper_xprt);
2517
2518		upper_transport->sock = sock;
2519		upper_transport->inet = sk;
2520		upper_transport->file = lower_transport->file;
2521
2522		release_sock(sk);
2523
2524		/* Reset lower_transport before shutting down its clnt */
2525		mutex_lock(&lower_transport->recv_mutex);
2526		lower_transport->inet = NULL;
2527		lower_transport->sock = NULL;
2528		lower_transport->file = NULL;
2529
2530		xprt_clear_connected(lower_xprt);
2531		xs_sock_reset_connection_flags(lower_xprt);
2532		xs_stream_reset_connect(lower_transport);
2533		mutex_unlock(&lower_transport->recv_mutex);
2534	}
2535
2536	if (!xprt_bound(upper_xprt))
2537		return -ENOTCONN;
2538
2539	xs_set_memalloc(upper_xprt);
2540
2541	if (!xprt_test_and_set_connected(upper_xprt)) {
2542		upper_xprt->connect_cookie++;
2543		clear_bit(XPRT_SOCK_CONNECTING, &upper_transport->sock_state);
2544		xprt_clear_connecting(upper_xprt);
2545
2546		upper_xprt->stat.connect_count++;
2547		upper_xprt->stat.connect_time += (long)jiffies -
2548					   upper_xprt->stat.connect_start;
2549		xs_run_error_worker(upper_transport, XPRT_SOCK_WAKE_PENDING);
2550	}
2551	return 0;
2552}
2553
2554/**
2555 * xs_tls_handshake_done - TLS handshake completion handler
2556 * @data: address of xprt to wake
2557 * @status: status of handshake
2558 * @peerid: serial number of key containing the remote's identity
2559 *
2560 */
2561static void xs_tls_handshake_done(void *data, int status, key_serial_t peerid)
2562{
2563	struct rpc_xprt *lower_xprt = data;
2564	struct sock_xprt *lower_transport =
2565				container_of(lower_xprt, struct sock_xprt, xprt);
2566
2567	lower_transport->xprt_err = status ? -EACCES : 0;
2568	complete(&lower_transport->handshake_done);
2569	xprt_put(lower_xprt);
2570}
2571
2572static int xs_tls_handshake_sync(struct rpc_xprt *lower_xprt, struct xprtsec_parms *xprtsec)
2573{
2574	struct sock_xprt *lower_transport =
2575				container_of(lower_xprt, struct sock_xprt, xprt);
2576	struct tls_handshake_args args = {
2577		.ta_sock	= lower_transport->sock,
2578		.ta_done	= xs_tls_handshake_done,
2579		.ta_data	= xprt_get(lower_xprt),
2580		.ta_peername	= lower_xprt->servername,
2581	};
2582	struct sock *sk = lower_transport->inet;
2583	int rc;
2584
2585	init_completion(&lower_transport->handshake_done);
2586	set_bit(XPRT_SOCK_IGNORE_RECV, &lower_transport->sock_state);
2587	lower_transport->xprt_err = -ETIMEDOUT;
2588	switch (xprtsec->policy) {
2589	case RPC_XPRTSEC_TLS_ANON:
2590		rc = tls_client_hello_anon(&args, GFP_KERNEL);
2591		if (rc)
2592			goto out_put_xprt;
2593		break;
2594	case RPC_XPRTSEC_TLS_X509:
2595		args.ta_my_cert = xprtsec->cert_serial;
2596		args.ta_my_privkey = xprtsec->privkey_serial;
2597		rc = tls_client_hello_x509(&args, GFP_KERNEL);
2598		if (rc)
2599			goto out_put_xprt;
2600		break;
2601	default:
2602		rc = -EACCES;
2603		goto out_put_xprt;
2604	}
2605
2606	rc = wait_for_completion_interruptible_timeout(&lower_transport->handshake_done,
2607						       XS_TLS_HANDSHAKE_TO);
2608	if (rc <= 0) {
2609		if (!tls_handshake_cancel(sk)) {
2610			if (rc == 0)
2611				rc = -ETIMEDOUT;
2612			goto out_put_xprt;
2613		}
2614	}
2615
2616	rc = lower_transport->xprt_err;
2617
2618out:
2619	xs_stream_reset_connect(lower_transport);
2620	clear_bit(XPRT_SOCK_IGNORE_RECV, &lower_transport->sock_state);
2621	return rc;
2622
2623out_put_xprt:
2624	xprt_put(lower_xprt);
2625	goto out;
2626}
2627
2628/**
2629 * xs_tcp_tls_setup_socket - establish a TLS session on a TCP socket
2630 * @work: queued work item
2631 *
2632 * Invoked by a work queue tasklet.
2633 *
2634 * For RPC-with-TLS, there is a two-stage connection process.
2635 *
2636 * The "upper-layer xprt" is visible to the RPC consumer. Once it has
2637 * been marked connected, the consumer knows that a TCP connection and
2638 * a TLS session have been established.
2639 *
2640 * A "lower-layer xprt", created in this function, handles the mechanics
2641 * of connecting the TCP socket, performing the RPC_AUTH_TLS probe, and
2642 * then driving the TLS handshake. Once all that is complete, the upper
2643 * layer xprt is marked connected.
2644 */
2645static void xs_tcp_tls_setup_socket(struct work_struct *work)
2646{
2647	struct sock_xprt *upper_transport =
2648		container_of(work, struct sock_xprt, connect_worker.work);
2649	struct rpc_clnt *upper_clnt = upper_transport->clnt;
2650	struct rpc_xprt *upper_xprt = &upper_transport->xprt;
2651	struct rpc_create_args args = {
2652		.net		= upper_xprt->xprt_net,
2653		.protocol	= upper_xprt->prot,
2654		.address	= (struct sockaddr *)&upper_xprt->addr,
2655		.addrsize	= upper_xprt->addrlen,
2656		.timeout	= upper_clnt->cl_timeout,
2657		.servername	= upper_xprt->servername,
2658		.program	= upper_clnt->cl_program,
2659		.prognumber	= upper_clnt->cl_prog,
2660		.version	= upper_clnt->cl_vers,
2661		.authflavor	= RPC_AUTH_TLS,
2662		.cred		= upper_clnt->cl_cred,
2663		.xprtsec	= {
2664			.policy		= RPC_XPRTSEC_NONE,
2665		},
2666		.stats		= upper_clnt->cl_stats,
2667	};
2668	unsigned int pflags = current->flags;
2669	struct rpc_clnt *lower_clnt;
2670	struct rpc_xprt *lower_xprt;
2671	int status;
2672
2673	if (atomic_read(&upper_xprt->swapper))
2674		current->flags |= PF_MEMALLOC;
2675
2676	xs_stream_start_connect(upper_transport);
2677
2678	/* This implicitly sends an RPC_AUTH_TLS probe */
2679	lower_clnt = rpc_create(&args);
2680	if (IS_ERR(lower_clnt)) {
2681		trace_rpc_tls_unavailable(upper_clnt, upper_xprt);
2682		clear_bit(XPRT_SOCK_CONNECTING, &upper_transport->sock_state);
2683		xprt_clear_connecting(upper_xprt);
2684		xprt_wake_pending_tasks(upper_xprt, PTR_ERR(lower_clnt));
2685		xs_run_error_worker(upper_transport, XPRT_SOCK_WAKE_PENDING);
2686		goto out_unlock;
2687	}
2688
2689	/* RPC_AUTH_TLS probe was successful. Try a TLS handshake on
2690	 * the lower xprt.
2691	 */
2692	rcu_read_lock();
2693	lower_xprt = rcu_dereference(lower_clnt->cl_xprt);
2694	rcu_read_unlock();
2695
2696	if (wait_on_bit_lock(&lower_xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2697		goto out_unlock;
2698
2699	status = xs_tls_handshake_sync(lower_xprt, &upper_xprt->xprtsec);
2700	if (status) {
2701		trace_rpc_tls_not_started(upper_clnt, upper_xprt);
2702		goto out_close;
2703	}
2704
2705	status = xs_tcp_tls_finish_connecting(lower_xprt, upper_transport);
2706	if (status)
2707		goto out_close;
2708	xprt_release_write(lower_xprt, NULL);
2709
2710	trace_rpc_socket_connect(upper_xprt, upper_transport->sock, 0);
2711	if (!xprt_test_and_set_connected(upper_xprt)) {
2712		upper_xprt->connect_cookie++;
2713		clear_bit(XPRT_SOCK_CONNECTING, &upper_transport->sock_state);
2714		xprt_clear_connecting(upper_xprt);
2715
2716		upper_xprt->stat.connect_count++;
2717		upper_xprt->stat.connect_time += (long)jiffies -
2718					   upper_xprt->stat.connect_start;
2719		xs_run_error_worker(upper_transport, XPRT_SOCK_WAKE_PENDING);
2720	}
2721	rpc_shutdown_client(lower_clnt);
2722
2723out_unlock:
2724	current_restore_flags(pflags, PF_MEMALLOC);
2725	upper_transport->clnt = NULL;
2726	xprt_unlock_connect(upper_xprt, upper_transport);
2727	return;
2728
2729out_close:
2730	xprt_release_write(lower_xprt, NULL);
2731	rpc_shutdown_client(lower_clnt);
2732
2733	/* xprt_force_disconnect() wakes tasks with a fixed tk_status code.
2734	 * Wake them first here to ensure they get our tk_status code.
2735	 */
2736	xprt_wake_pending_tasks(upper_xprt, status);
2737	xs_tcp_force_close(upper_xprt);
2738	xprt_clear_connecting(upper_xprt);
2739	goto out_unlock;
2740}
2741
2742/**
2743 * xs_connect - connect a socket to a remote endpoint
2744 * @xprt: pointer to transport structure
2745 * @task: address of RPC task that manages state of connect request
2746 *
2747 * TCP: If the remote end dropped the connection, delay reconnecting.
2748 *
2749 * UDP socket connects are synchronous, but we use a work queue anyway
2750 * to guarantee that even unprivileged user processes can set up a
2751 * socket on a privileged port.
2752 *
2753 * If a UDP socket connect fails, the delay behavior here prevents
2754 * retry floods (hard mounts).
2755 */
2756static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2757{
2758	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2759	unsigned long delay = 0;
2760
2761	WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2762
2763	if (transport->sock != NULL) {
2764		dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2765			"seconds\n", xprt, xprt->reestablish_timeout / HZ);
2766
2767		delay = xprt_reconnect_delay(xprt);
2768		xprt_reconnect_backoff(xprt, XS_TCP_INIT_REEST_TO);
2769
2770	} else
2771		dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2772
2773	transport->clnt = task->tk_client;
2774	queue_delayed_work(xprtiod_workqueue,
2775			&transport->connect_worker,
2776			delay);
2777}
2778
2779static void xs_wake_disconnect(struct sock_xprt *transport)
2780{
2781	if (test_and_clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state))
2782		xs_tcp_force_close(&transport->xprt);
2783}
2784
2785static void xs_wake_write(struct sock_xprt *transport)
2786{
2787	if (test_and_clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state))
2788		xprt_write_space(&transport->xprt);
2789}
2790
2791static void xs_wake_error(struct sock_xprt *transport)
2792{
2793	int sockerr;
2794
2795	if (!test_and_clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2796		return;
2797	sockerr = xchg(&transport->xprt_err, 0);
2798	if (sockerr < 0) {
2799		xprt_wake_pending_tasks(&transport->xprt, sockerr);
2800		xs_tcp_force_close(&transport->xprt);
2801	}
2802}
2803
2804static void xs_wake_pending(struct sock_xprt *transport)
2805{
2806	if (test_and_clear_bit(XPRT_SOCK_WAKE_PENDING, &transport->sock_state))
2807		xprt_wake_pending_tasks(&transport->xprt, -EAGAIN);
2808}
2809
2810static void xs_error_handle(struct work_struct *work)
2811{
2812	struct sock_xprt *transport = container_of(work,
2813			struct sock_xprt, error_worker);
2814
2815	xs_wake_disconnect(transport);
2816	xs_wake_write(transport);
2817	xs_wake_error(transport);
2818	xs_wake_pending(transport);
2819}
2820
2821/**
2822 * xs_local_print_stats - display AF_LOCAL socket-specific stats
2823 * @xprt: rpc_xprt struct containing statistics
2824 * @seq: output file
2825 *
2826 */
2827static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2828{
2829	long idle_time = 0;
2830
2831	if (xprt_connected(xprt))
2832		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2833
2834	seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2835			"%llu %llu %lu %llu %llu\n",
2836			xprt->stat.bind_count,
2837			xprt->stat.connect_count,
2838			xprt->stat.connect_time / HZ,
2839			idle_time,
2840			xprt->stat.sends,
2841			xprt->stat.recvs,
2842			xprt->stat.bad_xids,
2843			xprt->stat.req_u,
2844			xprt->stat.bklog_u,
2845			xprt->stat.max_slots,
2846			xprt->stat.sending_u,
2847			xprt->stat.pending_u);
2848}
2849
2850/**
2851 * xs_udp_print_stats - display UDP socket-specific stats
2852 * @xprt: rpc_xprt struct containing statistics
2853 * @seq: output file
2854 *
2855 */
2856static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2857{
2858	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2859
2860	seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2861			"%lu %llu %llu\n",
2862			transport->srcport,
2863			xprt->stat.bind_count,
2864			xprt->stat.sends,
2865			xprt->stat.recvs,
2866			xprt->stat.bad_xids,
2867			xprt->stat.req_u,
2868			xprt->stat.bklog_u,
2869			xprt->stat.max_slots,
2870			xprt->stat.sending_u,
2871			xprt->stat.pending_u);
2872}
2873
2874/**
2875 * xs_tcp_print_stats - display TCP socket-specific stats
2876 * @xprt: rpc_xprt struct containing statistics
2877 * @seq: output file
2878 *
2879 */
2880static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2881{
2882	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2883	long idle_time = 0;
2884
2885	if (xprt_connected(xprt))
2886		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2887
2888	seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2889			"%llu %llu %lu %llu %llu\n",
2890			transport->srcport,
2891			xprt->stat.bind_count,
2892			xprt->stat.connect_count,
2893			xprt->stat.connect_time / HZ,
2894			idle_time,
2895			xprt->stat.sends,
2896			xprt->stat.recvs,
2897			xprt->stat.bad_xids,
2898			xprt->stat.req_u,
2899			xprt->stat.bklog_u,
2900			xprt->stat.max_slots,
2901			xprt->stat.sending_u,
2902			xprt->stat.pending_u);
2903}
2904
2905/*
2906 * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2907 * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2908 * to use the server side send routines.
2909 */
2910static int bc_malloc(struct rpc_task *task)
2911{
2912	struct rpc_rqst *rqst = task->tk_rqstp;
2913	size_t size = rqst->rq_callsize;
2914	struct page *page;
2915	struct rpc_buffer *buf;
2916
2917	if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2918		WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2919			  size);
2920		return -EINVAL;
2921	}
2922
2923	page = alloc_page(GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
2924	if (!page)
2925		return -ENOMEM;
2926
2927	buf = page_address(page);
2928	buf->len = PAGE_SIZE;
2929
2930	rqst->rq_buffer = buf->data;
2931	rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2932	return 0;
2933}
2934
2935/*
2936 * Free the space allocated in the bc_alloc routine
2937 */
2938static void bc_free(struct rpc_task *task)
2939{
2940	void *buffer = task->tk_rqstp->rq_buffer;
2941	struct rpc_buffer *buf;
2942
2943	buf = container_of(buffer, struct rpc_buffer, data);
2944	free_page((unsigned long)buf);
2945}
2946
2947static int bc_sendto(struct rpc_rqst *req)
2948{
2949	struct xdr_buf *xdr = &req->rq_snd_buf;
2950	struct sock_xprt *transport =
2951			container_of(req->rq_xprt, struct sock_xprt, xprt);
2952	struct msghdr msg = {
2953		.msg_flags	= 0,
2954	};
2955	rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT |
2956					 (u32)xdr->len);
2957	unsigned int sent = 0;
2958	int err;
2959
2960	req->rq_xtime = ktime_get();
2961	err = xdr_alloc_bvec(xdr, rpc_task_gfp_mask());
2962	if (err < 0)
2963		return err;
2964	err = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, marker, &sent);
2965	xdr_free_bvec(xdr);
2966	if (err < 0 || sent != (xdr->len + sizeof(marker)))
2967		return -EAGAIN;
2968	return sent;
2969}
2970
2971/**
2972 * bc_send_request - Send a backchannel Call on a TCP socket
2973 * @req: rpc_rqst containing Call message to be sent
2974 *
2975 * xpt_mutex ensures @rqstp's whole message is written to the socket
2976 * without interruption.
2977 *
2978 * Return values:
2979 *   %0 if the message was sent successfully
2980 *   %ENOTCONN if the message was not sent
2981 */
2982static int bc_send_request(struct rpc_rqst *req)
2983{
2984	struct svc_xprt	*xprt;
2985	int len;
2986
2987	/*
2988	 * Get the server socket associated with this callback xprt
2989	 */
2990	xprt = req->rq_xprt->bc_xprt;
2991
2992	/*
2993	 * Grab the mutex to serialize data as the connection is shared
2994	 * with the fore channel
2995	 */
2996	mutex_lock(&xprt->xpt_mutex);
2997	if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2998		len = -ENOTCONN;
2999	else
3000		len = bc_sendto(req);
3001	mutex_unlock(&xprt->xpt_mutex);
3002
3003	if (len > 0)
3004		len = 0;
3005
3006	return len;
3007}
3008
3009static void bc_close(struct rpc_xprt *xprt)
3010{
3011	xprt_disconnect_done(xprt);
3012}
3013
3014static void bc_destroy(struct rpc_xprt *xprt)
3015{
3016	dprintk("RPC:       bc_destroy xprt %p\n", xprt);
3017
3018	xs_xprt_free(xprt);
3019	module_put(THIS_MODULE);
3020}
3021
3022static const struct rpc_xprt_ops xs_local_ops = {
3023	.reserve_xprt		= xprt_reserve_xprt,
3024	.release_xprt		= xprt_release_xprt,
3025	.alloc_slot		= xprt_alloc_slot,
3026	.free_slot		= xprt_free_slot,
3027	.rpcbind		= xs_local_rpcbind,
3028	.set_port		= xs_local_set_port,
3029	.connect		= xs_local_connect,
3030	.buf_alloc		= rpc_malloc,
3031	.buf_free		= rpc_free,
3032	.prepare_request	= xs_stream_prepare_request,
3033	.send_request		= xs_local_send_request,
3034	.abort_send_request	= xs_stream_abort_send_request,
3035	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
3036	.close			= xs_close,
3037	.destroy		= xs_destroy,
3038	.print_stats		= xs_local_print_stats,
3039	.enable_swap		= xs_enable_swap,
3040	.disable_swap		= xs_disable_swap,
3041};
3042
3043static const struct rpc_xprt_ops xs_udp_ops = {
3044	.set_buffer_size	= xs_udp_set_buffer_size,
3045	.reserve_xprt		= xprt_reserve_xprt_cong,
3046	.release_xprt		= xprt_release_xprt_cong,
3047	.alloc_slot		= xprt_alloc_slot,
3048	.free_slot		= xprt_free_slot,
3049	.rpcbind		= rpcb_getport_async,
3050	.set_port		= xs_set_port,
3051	.connect		= xs_connect,
3052	.get_srcaddr		= xs_sock_srcaddr,
3053	.get_srcport		= xs_sock_srcport,
3054	.buf_alloc		= rpc_malloc,
3055	.buf_free		= rpc_free,
3056	.send_request		= xs_udp_send_request,
3057	.wait_for_reply_request	= xprt_wait_for_reply_request_rtt,
3058	.timer			= xs_udp_timer,
3059	.release_request	= xprt_release_rqst_cong,
3060	.close			= xs_close,
3061	.destroy		= xs_destroy,
3062	.print_stats		= xs_udp_print_stats,
3063	.enable_swap		= xs_enable_swap,
3064	.disable_swap		= xs_disable_swap,
3065	.inject_disconnect	= xs_inject_disconnect,
3066};
3067
3068static const struct rpc_xprt_ops xs_tcp_ops = {
3069	.reserve_xprt		= xprt_reserve_xprt,
3070	.release_xprt		= xprt_release_xprt,
3071	.alloc_slot		= xprt_alloc_slot,
3072	.free_slot		= xprt_free_slot,
3073	.rpcbind		= rpcb_getport_async,
3074	.set_port		= xs_set_port,
3075	.connect		= xs_connect,
3076	.get_srcaddr		= xs_sock_srcaddr,
3077	.get_srcport		= xs_sock_srcport,
3078	.buf_alloc		= rpc_malloc,
3079	.buf_free		= rpc_free,
3080	.prepare_request	= xs_stream_prepare_request,
3081	.send_request		= xs_tcp_send_request,
3082	.abort_send_request	= xs_stream_abort_send_request,
3083	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
3084	.close			= xs_tcp_shutdown,
3085	.destroy		= xs_destroy,
3086	.set_connect_timeout	= xs_tcp_set_connect_timeout,
3087	.print_stats		= xs_tcp_print_stats,
3088	.enable_swap		= xs_enable_swap,
3089	.disable_swap		= xs_disable_swap,
3090	.inject_disconnect	= xs_inject_disconnect,
3091#ifdef CONFIG_SUNRPC_BACKCHANNEL
3092	.bc_setup		= xprt_setup_bc,
3093	.bc_maxpayload		= xs_tcp_bc_maxpayload,
3094	.bc_num_slots		= xprt_bc_max_slots,
3095	.bc_free_rqst		= xprt_free_bc_rqst,
3096	.bc_destroy		= xprt_destroy_bc,
3097#endif
3098};
3099
3100/*
3101 * The rpc_xprt_ops for the server backchannel
3102 */
3103
3104static const struct rpc_xprt_ops bc_tcp_ops = {
3105	.reserve_xprt		= xprt_reserve_xprt,
3106	.release_xprt		= xprt_release_xprt,
3107	.alloc_slot		= xprt_alloc_slot,
3108	.free_slot		= xprt_free_slot,
3109	.buf_alloc		= bc_malloc,
3110	.buf_free		= bc_free,
3111	.send_request		= bc_send_request,
3112	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
3113	.close			= bc_close,
3114	.destroy		= bc_destroy,
3115	.print_stats		= xs_tcp_print_stats,
3116	.enable_swap		= xs_enable_swap,
3117	.disable_swap		= xs_disable_swap,
3118	.inject_disconnect	= xs_inject_disconnect,
3119};
3120
3121static int xs_init_anyaddr(const int family, struct sockaddr *sap)
3122{
3123	static const struct sockaddr_in sin = {
3124		.sin_family		= AF_INET,
3125		.sin_addr.s_addr	= htonl(INADDR_ANY),
3126	};
3127	static const struct sockaddr_in6 sin6 = {
3128		.sin6_family		= AF_INET6,
3129		.sin6_addr		= IN6ADDR_ANY_INIT,
3130	};
3131
3132	switch (family) {
3133	case AF_LOCAL:
3134		break;
3135	case AF_INET:
3136		memcpy(sap, &sin, sizeof(sin));
3137		break;
3138	case AF_INET6:
3139		memcpy(sap, &sin6, sizeof(sin6));
3140		break;
3141	default:
3142		dprintk("RPC:       %s: Bad address family\n", __func__);
3143		return -EAFNOSUPPORT;
3144	}
3145	return 0;
3146}
3147
3148static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
3149				      unsigned int slot_table_size,
3150				      unsigned int max_slot_table_size)
3151{
3152	struct rpc_xprt *xprt;
3153	struct sock_xprt *new;
3154
3155	if (args->addrlen > sizeof(xprt->addr)) {
3156		dprintk("RPC:       xs_setup_xprt: address too large\n");
3157		return ERR_PTR(-EBADF);
3158	}
3159
3160	xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
3161			max_slot_table_size);
3162	if (xprt == NULL) {
3163		dprintk("RPC:       xs_setup_xprt: couldn't allocate "
3164				"rpc_xprt\n");
3165		return ERR_PTR(-ENOMEM);
3166	}
3167
3168	new = container_of(xprt, struct sock_xprt, xprt);
3169	mutex_init(&new->recv_mutex);
3170	memcpy(&xprt->addr, args->dstaddr, args->addrlen);
3171	xprt->addrlen = args->addrlen;
3172	if (args->srcaddr)
3173		memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
3174	else {
3175		int err;
3176		err = xs_init_anyaddr(args->dstaddr->sa_family,
3177					(struct sockaddr *)&new->srcaddr);
3178		if (err != 0) {
3179			xprt_free(xprt);
3180			return ERR_PTR(err);
3181		}
3182	}
3183
3184	return xprt;
3185}
3186
3187static const struct rpc_timeout xs_local_default_timeout = {
3188	.to_initval = 10 * HZ,
3189	.to_maxval = 10 * HZ,
3190	.to_retries = 2,
3191};
3192
3193/**
3194 * xs_setup_local - Set up transport to use an AF_LOCAL socket
3195 * @args: rpc transport creation arguments
3196 *
3197 * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
3198 */
3199static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
3200{
3201	struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
3202	struct sock_xprt *transport;
3203	struct rpc_xprt *xprt;
3204	struct rpc_xprt *ret;
3205
3206	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3207			xprt_max_tcp_slot_table_entries);
3208	if (IS_ERR(xprt))
3209		return xprt;
3210	transport = container_of(xprt, struct sock_xprt, xprt);
3211
3212	xprt->prot = 0;
3213	xprt->xprt_class = &xs_local_transport;
3214	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3215
3216	xprt->bind_timeout = XS_BIND_TO;
3217	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
3218	xprt->idle_timeout = XS_IDLE_DISC_TO;
3219
3220	xprt->ops = &xs_local_ops;
3221	xprt->timeout = &xs_local_default_timeout;
3222
3223	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
3224	INIT_WORK(&transport->error_worker, xs_error_handle);
3225	INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket);
3226
3227	switch (sun->sun_family) {
3228	case AF_LOCAL:
3229		if (sun->sun_path[0] != '/' && sun->sun_path[0] != '\0') {
3230			dprintk("RPC:       bad AF_LOCAL address: %s\n",
3231					sun->sun_path);
3232			ret = ERR_PTR(-EINVAL);
3233			goto out_err;
3234		}
3235		xprt_set_bound(xprt);
3236		xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
3237		break;
3238	default:
3239		ret = ERR_PTR(-EAFNOSUPPORT);
3240		goto out_err;
3241	}
3242
3243	dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
3244			xprt->address_strings[RPC_DISPLAY_ADDR]);
3245
3246	if (try_module_get(THIS_MODULE))
3247		return xprt;
3248	ret = ERR_PTR(-EINVAL);
3249out_err:
3250	xs_xprt_free(xprt);
3251	return ret;
3252}
3253
3254static const struct rpc_timeout xs_udp_default_timeout = {
3255	.to_initval = 5 * HZ,
3256	.to_maxval = 30 * HZ,
3257	.to_increment = 5 * HZ,
3258	.to_retries = 5,
3259};
3260
3261/**
3262 * xs_setup_udp - Set up transport to use a UDP socket
3263 * @args: rpc transport creation arguments
3264 *
3265 */
3266static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
3267{
3268	struct sockaddr *addr = args->dstaddr;
3269	struct rpc_xprt *xprt;
3270	struct sock_xprt *transport;
3271	struct rpc_xprt *ret;
3272
3273	xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
3274			xprt_udp_slot_table_entries);
3275	if (IS_ERR(xprt))
3276		return xprt;
3277	transport = container_of(xprt, struct sock_xprt, xprt);
3278
3279	xprt->prot = IPPROTO_UDP;
3280	xprt->xprt_class = &xs_udp_transport;
3281	/* XXX: header size can vary due to auth type, IPv6, etc. */
3282	xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
3283
3284	xprt->bind_timeout = XS_BIND_TO;
3285	xprt->reestablish_timeout = XS_UDP_REEST_TO;
3286	xprt->idle_timeout = XS_IDLE_DISC_TO;
3287
3288	xprt->ops = &xs_udp_ops;
3289
3290	xprt->timeout = &xs_udp_default_timeout;
3291
3292	INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
3293	INIT_WORK(&transport->error_worker, xs_error_handle);
3294	INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
3295
3296	switch (addr->sa_family) {
3297	case AF_INET:
3298		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3299			xprt_set_bound(xprt);
3300
3301		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
3302		break;
3303	case AF_INET6:
3304		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3305			xprt_set_bound(xprt);
3306
3307		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
3308		break;
3309	default:
3310		ret = ERR_PTR(-EAFNOSUPPORT);
3311		goto out_err;
3312	}
3313
3314	if (xprt_bound(xprt))
3315		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3316				xprt->address_strings[RPC_DISPLAY_ADDR],
3317				xprt->address_strings[RPC_DISPLAY_PORT],
3318				xprt->address_strings[RPC_DISPLAY_PROTO]);
3319	else
3320		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3321				xprt->address_strings[RPC_DISPLAY_ADDR],
3322				xprt->address_strings[RPC_DISPLAY_PROTO]);
3323
3324	if (try_module_get(THIS_MODULE))
3325		return xprt;
3326	ret = ERR_PTR(-EINVAL);
3327out_err:
3328	xs_xprt_free(xprt);
3329	return ret;
3330}
3331
3332static const struct rpc_timeout xs_tcp_default_timeout = {
3333	.to_initval = 60 * HZ,
3334	.to_maxval = 60 * HZ,
3335	.to_retries = 2,
3336};
3337
3338/**
3339 * xs_setup_tcp - Set up transport to use a TCP socket
3340 * @args: rpc transport creation arguments
3341 *
3342 */
3343static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
3344{
3345	struct sockaddr *addr = args->dstaddr;
3346	struct rpc_xprt *xprt;
3347	struct sock_xprt *transport;
3348	struct rpc_xprt *ret;
3349	unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
3350
3351	if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
3352		max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
3353
3354	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3355			max_slot_table_size);
3356	if (IS_ERR(xprt))
3357		return xprt;
3358	transport = container_of(xprt, struct sock_xprt, xprt);
3359
3360	xprt->prot = IPPROTO_TCP;
3361	xprt->xprt_class = &xs_tcp_transport;
3362	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3363
3364	xprt->bind_timeout = XS_BIND_TO;
3365	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
3366	xprt->idle_timeout = XS_IDLE_DISC_TO;
3367
3368	xprt->ops = &xs_tcp_ops;
3369	xprt->timeout = &xs_tcp_default_timeout;
3370
3371	xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
3372	if (args->reconnect_timeout)
3373		xprt->max_reconnect_timeout = args->reconnect_timeout;
3374
3375	xprt->connect_timeout = xprt->timeout->to_initval *
3376		(xprt->timeout->to_retries + 1);
3377	if (args->connect_timeout)
3378		xs_tcp_do_set_connect_timeout(xprt, args->connect_timeout);
3379
3380	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
3381	INIT_WORK(&transport->error_worker, xs_error_handle);
3382	INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
3383
3384	switch (addr->sa_family) {
3385	case AF_INET:
3386		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3387			xprt_set_bound(xprt);
3388
3389		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
3390		break;
3391	case AF_INET6:
3392		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3393			xprt_set_bound(xprt);
3394
3395		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
3396		break;
3397	default:
3398		ret = ERR_PTR(-EAFNOSUPPORT);
3399		goto out_err;
3400	}
3401
3402	if (xprt_bound(xprt))
3403		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3404				xprt->address_strings[RPC_DISPLAY_ADDR],
3405				xprt->address_strings[RPC_DISPLAY_PORT],
3406				xprt->address_strings[RPC_DISPLAY_PROTO]);
3407	else
3408		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3409				xprt->address_strings[RPC_DISPLAY_ADDR],
3410				xprt->address_strings[RPC_DISPLAY_PROTO]);
3411
3412	if (try_module_get(THIS_MODULE))
3413		return xprt;
3414	ret = ERR_PTR(-EINVAL);
3415out_err:
3416	xs_xprt_free(xprt);
3417	return ret;
3418}
3419
3420/**
3421 * xs_setup_tcp_tls - Set up transport to use a TCP with TLS
3422 * @args: rpc transport creation arguments
3423 *
3424 */
3425static struct rpc_xprt *xs_setup_tcp_tls(struct xprt_create *args)
3426{
3427	struct sockaddr *addr = args->dstaddr;
3428	struct rpc_xprt *xprt;
3429	struct sock_xprt *transport;
3430	struct rpc_xprt *ret;
3431	unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
3432
3433	if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
3434		max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
3435
3436	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3437			     max_slot_table_size);
3438	if (IS_ERR(xprt))
3439		return xprt;
3440	transport = container_of(xprt, struct sock_xprt, xprt);
3441
3442	xprt->prot = IPPROTO_TCP;
3443	xprt->xprt_class = &xs_tcp_transport;
3444	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3445
3446	xprt->bind_timeout = XS_BIND_TO;
3447	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
3448	xprt->idle_timeout = XS_IDLE_DISC_TO;
3449
3450	xprt->ops = &xs_tcp_ops;
3451	xprt->timeout = &xs_tcp_default_timeout;
3452
3453	xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
3454	xprt->connect_timeout = xprt->timeout->to_initval *
3455		(xprt->timeout->to_retries + 1);
3456
3457	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
3458	INIT_WORK(&transport->error_worker, xs_error_handle);
3459
3460	switch (args->xprtsec.policy) {
3461	case RPC_XPRTSEC_TLS_ANON:
3462	case RPC_XPRTSEC_TLS_X509:
3463		xprt->xprtsec = args->xprtsec;
3464		INIT_DELAYED_WORK(&transport->connect_worker,
3465				  xs_tcp_tls_setup_socket);
3466		break;
3467	default:
3468		ret = ERR_PTR(-EACCES);
3469		goto out_err;
3470	}
3471
3472	switch (addr->sa_family) {
3473	case AF_INET:
3474		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3475			xprt_set_bound(xprt);
3476
3477		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
3478		break;
3479	case AF_INET6:
3480		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3481			xprt_set_bound(xprt);
3482
3483		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
3484		break;
3485	default:
3486		ret = ERR_PTR(-EAFNOSUPPORT);
3487		goto out_err;
3488	}
3489
3490	if (xprt_bound(xprt))
3491		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3492			xprt->address_strings[RPC_DISPLAY_ADDR],
3493			xprt->address_strings[RPC_DISPLAY_PORT],
3494			xprt->address_strings[RPC_DISPLAY_PROTO]);
3495	else
3496		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3497			xprt->address_strings[RPC_DISPLAY_ADDR],
3498			xprt->address_strings[RPC_DISPLAY_PROTO]);
3499
3500	if (try_module_get(THIS_MODULE))
3501		return xprt;
3502	ret = ERR_PTR(-EINVAL);
3503out_err:
3504	xs_xprt_free(xprt);
3505	return ret;
3506}
3507
3508/**
3509 * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
3510 * @args: rpc transport creation arguments
3511 *
3512 */
3513static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
3514{
3515	struct sockaddr *addr = args->dstaddr;
3516	struct rpc_xprt *xprt;
3517	struct sock_xprt *transport;
3518	struct svc_sock *bc_sock;
3519	struct rpc_xprt *ret;
3520
3521	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3522			xprt_tcp_slot_table_entries);
3523	if (IS_ERR(xprt))
3524		return xprt;
3525	transport = container_of(xprt, struct sock_xprt, xprt);
3526
3527	xprt->prot = IPPROTO_TCP;
3528	xprt->xprt_class = &xs_bc_tcp_transport;
3529	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3530	xprt->timeout = &xs_tcp_default_timeout;
3531
3532	/* backchannel */
3533	xprt_set_bound(xprt);
3534	xprt->bind_timeout = 0;
3535	xprt->reestablish_timeout = 0;
3536	xprt->idle_timeout = 0;
3537
3538	xprt->ops = &bc_tcp_ops;
3539
3540	switch (addr->sa_family) {
3541	case AF_INET:
3542		xs_format_peer_addresses(xprt, "tcp",
3543					 RPCBIND_NETID_TCP);
3544		break;
3545	case AF_INET6:
3546		xs_format_peer_addresses(xprt, "tcp",
3547				   RPCBIND_NETID_TCP6);
3548		break;
3549	default:
3550		ret = ERR_PTR(-EAFNOSUPPORT);
3551		goto out_err;
3552	}
3553
3554	dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3555			xprt->address_strings[RPC_DISPLAY_ADDR],
3556			xprt->address_strings[RPC_DISPLAY_PORT],
3557			xprt->address_strings[RPC_DISPLAY_PROTO]);
3558
3559	/*
3560	 * Once we've associated a backchannel xprt with a connection,
3561	 * we want to keep it around as long as the connection lasts,
3562	 * in case we need to start using it for a backchannel again;
3563	 * this reference won't be dropped until bc_xprt is destroyed.
3564	 */
3565	xprt_get(xprt);
3566	args->bc_xprt->xpt_bc_xprt = xprt;
3567	xprt->bc_xprt = args->bc_xprt;
3568	bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3569	transport->sock = bc_sock->sk_sock;
3570	transport->inet = bc_sock->sk_sk;
3571
3572	/*
3573	 * Since we don't want connections for the backchannel, we set
3574	 * the xprt status to connected
3575	 */
3576	xprt_set_connected(xprt);
3577
3578	if (try_module_get(THIS_MODULE))
3579		return xprt;
3580
3581	args->bc_xprt->xpt_bc_xprt = NULL;
3582	args->bc_xprt->xpt_bc_xps = NULL;
3583	xprt_put(xprt);
3584	ret = ERR_PTR(-EINVAL);
3585out_err:
3586	xs_xprt_free(xprt);
3587	return ret;
3588}
3589
3590static struct xprt_class	xs_local_transport = {
3591	.list		= LIST_HEAD_INIT(xs_local_transport.list),
3592	.name		= "named UNIX socket",
3593	.owner		= THIS_MODULE,
3594	.ident		= XPRT_TRANSPORT_LOCAL,
3595	.setup		= xs_setup_local,
3596	.netid		= { "" },
3597};
3598
3599static struct xprt_class	xs_udp_transport = {
3600	.list		= LIST_HEAD_INIT(xs_udp_transport.list),
3601	.name		= "udp",
3602	.owner		= THIS_MODULE,
3603	.ident		= XPRT_TRANSPORT_UDP,
3604	.setup		= xs_setup_udp,
3605	.netid		= { "udp", "udp6", "" },
3606};
3607
3608static struct xprt_class	xs_tcp_transport = {
3609	.list		= LIST_HEAD_INIT(xs_tcp_transport.list),
3610	.name		= "tcp",
3611	.owner		= THIS_MODULE,
3612	.ident		= XPRT_TRANSPORT_TCP,
3613	.setup		= xs_setup_tcp,
3614	.netid		= { "tcp", "tcp6", "" },
3615};
3616
3617static struct xprt_class	xs_tcp_tls_transport = {
3618	.list		= LIST_HEAD_INIT(xs_tcp_tls_transport.list),
3619	.name		= "tcp-with-tls",
3620	.owner		= THIS_MODULE,
3621	.ident		= XPRT_TRANSPORT_TCP_TLS,
3622	.setup		= xs_setup_tcp_tls,
3623	.netid		= { "tcp", "tcp6", "" },
3624};
3625
3626static struct xprt_class	xs_bc_tcp_transport = {
3627	.list		= LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3628	.name		= "tcp NFSv4.1 backchannel",
3629	.owner		= THIS_MODULE,
3630	.ident		= XPRT_TRANSPORT_BC_TCP,
3631	.setup		= xs_setup_bc_tcp,
3632	.netid		= { "" },
3633};
3634
3635/**
3636 * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3637 *
3638 */
3639int init_socket_xprt(void)
3640{
3641	if (!sunrpc_table_header)
3642		sunrpc_table_header = register_sysctl("sunrpc", xs_tunables_table);
3643
3644	xprt_register_transport(&xs_local_transport);
3645	xprt_register_transport(&xs_udp_transport);
3646	xprt_register_transport(&xs_tcp_transport);
3647	xprt_register_transport(&xs_tcp_tls_transport);
3648	xprt_register_transport(&xs_bc_tcp_transport);
3649
3650	return 0;
3651}
3652
3653/**
3654 * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3655 *
3656 */
3657void cleanup_socket_xprt(void)
3658{
3659	if (sunrpc_table_header) {
3660		unregister_sysctl_table(sunrpc_table_header);
3661		sunrpc_table_header = NULL;
3662	}
3663
3664	xprt_unregister_transport(&xs_local_transport);
3665	xprt_unregister_transport(&xs_udp_transport);
3666	xprt_unregister_transport(&xs_tcp_transport);
3667	xprt_unregister_transport(&xs_tcp_tls_transport);
3668	xprt_unregister_transport(&xs_bc_tcp_transport);
3669}
3670
3671static int param_set_portnr(const char *val, const struct kernel_param *kp)
3672{
3673	return param_set_uint_minmax(val, kp,
3674			RPC_MIN_RESVPORT,
3675			RPC_MAX_RESVPORT);
3676}
3677
3678static const struct kernel_param_ops param_ops_portnr = {
3679	.set = param_set_portnr,
3680	.get = param_get_uint,
3681};
3682
3683#define param_check_portnr(name, p) \
3684	__param_check(name, p, unsigned int);
3685
3686module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3687module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3688
3689static int param_set_slot_table_size(const char *val,
3690				     const struct kernel_param *kp)
3691{
3692	return param_set_uint_minmax(val, kp,
3693			RPC_MIN_SLOT_TABLE,
3694			RPC_MAX_SLOT_TABLE);
3695}
3696
3697static const struct kernel_param_ops param_ops_slot_table_size = {
3698	.set = param_set_slot_table_size,
3699	.get = param_get_uint,
3700};
3701
3702#define param_check_slot_table_size(name, p) \
3703	__param_check(name, p, unsigned int);
3704
3705static int param_set_max_slot_table_size(const char *val,
3706				     const struct kernel_param *kp)
3707{
3708	return param_set_uint_minmax(val, kp,
3709			RPC_MIN_SLOT_TABLE,
3710			RPC_MAX_SLOT_TABLE_LIMIT);
3711}
3712
3713static const struct kernel_param_ops param_ops_max_slot_table_size = {
3714	.set = param_set_max_slot_table_size,
3715	.get = param_get_uint,
3716};
3717
3718#define param_check_max_slot_table_size(name, p) \
3719	__param_check(name, p, unsigned int);
3720
3721module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3722		   slot_table_size, 0644);
3723module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3724		   max_slot_table_size, 0644);
3725module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3726		   slot_table_size, 0644);
3727