xref: /linux/net/sunrpc/xprtsock.c (revision 35b1b538d422fd765d88fbdaaa6e06ee466d9f93)
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.h>
51 #include <net/tls_prot.h>
52 #include <net/handshake.h>
53 
54 #include <linux/bvec.h>
55 #include <linux/highmem.h>
56 #include <linux/uio.h>
57 #include <linux/sched/mm.h>
58 
59 #include <trace/events/sock.h>
60 #include <trace/events/sunrpc.h>
61 
62 #include "socklib.h"
63 #include "sunrpc.h"
64 
65 static void xs_close(struct rpc_xprt *xprt);
66 static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock);
67 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
68 		struct socket *sock);
69 
70 /*
71  * xprtsock tunables
72  */
73 static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
74 static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
75 static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
76 
77 static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
78 static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
79 
80 #define XS_TCP_LINGER_TO	(15U * HZ)
81 static 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 
92 static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
93 static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
94 static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
95 static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
96 static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
97 
98 static struct ctl_table_header *sunrpc_table_header;
99 
100 static struct xprt_class xs_local_transport;
101 static struct xprt_class xs_udp_transport;
102 static struct xprt_class xs_tcp_transport;
103 static struct xprt_class xs_tcp_tls_transport;
104 static 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  */
110 static 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 /*
167  * Wait duration for a reply from the RPC portmapper.
168  */
169 #define XS_BIND_TO		(60U * HZ)
170 
171 /*
172  * Delay if a UDP socket connect error occurs.  This is most likely some
173  * kind of resource problem on the local host.
174  */
175 #define XS_UDP_REEST_TO		(2U * HZ)
176 
177 /*
178  * The reestablish timeout allows clients to delay for a bit before attempting
179  * to reconnect to a server that just dropped our connection.
180  *
181  * We implement an exponential backoff when trying to reestablish a TCP
182  * transport connection with the server.  Some servers like to drop a TCP
183  * connection when they are overworked, so we start with a short timeout and
184  * increase over time if the server is down or not responding.
185  */
186 #define XS_TCP_INIT_REEST_TO	(3U * HZ)
187 
188 /*
189  * TCP idle timeout; client drops the transport socket if it is idle
190  * for this long.  Note that we also timeout UDP sockets to prevent
191  * holding port numbers when there is no RPC traffic.
192  */
193 #define XS_IDLE_DISC_TO		(5U * 60 * HZ)
194 
195 /*
196  * TLS handshake timeout.
197  */
198 #define XS_TLS_HANDSHAKE_TO	(10U * HZ)
199 
200 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
201 # undef  RPC_DEBUG_DATA
202 # define RPCDBG_FACILITY	RPCDBG_TRANS
203 #endif
204 
205 #ifdef RPC_DEBUG_DATA
206 static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
207 {
208 	u8 *buf = (u8 *) packet;
209 	int j;
210 
211 	dprintk("RPC:       %s\n", msg);
212 	for (j = 0; j < count && j < 128; j += 4) {
213 		if (!(j & 31)) {
214 			if (j)
215 				dprintk("\n");
216 			dprintk("0x%04x ", j);
217 		}
218 		dprintk("%02x%02x%02x%02x ",
219 			buf[j], buf[j+1], buf[j+2], buf[j+3]);
220 	}
221 	dprintk("\n");
222 }
223 #else
224 static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
225 {
226 	/* NOP */
227 }
228 #endif
229 
230 static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
231 {
232 	return (struct rpc_xprt *) sk->sk_user_data;
233 }
234 
235 static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
236 {
237 	return (struct sockaddr *) &xprt->addr;
238 }
239 
240 static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
241 {
242 	return (struct sockaddr_un *) &xprt->addr;
243 }
244 
245 static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
246 {
247 	return (struct sockaddr_in *) &xprt->addr;
248 }
249 
250 static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
251 {
252 	return (struct sockaddr_in6 *) &xprt->addr;
253 }
254 
255 static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
256 {
257 	struct sockaddr *sap = xs_addr(xprt);
258 	struct sockaddr_in6 *sin6;
259 	struct sockaddr_in *sin;
260 	struct sockaddr_un *sun;
261 	char buf[128];
262 
263 	switch (sap->sa_family) {
264 	case AF_LOCAL:
265 		sun = xs_addr_un(xprt);
266 		if (sun->sun_path[0]) {
267 			strscpy(buf, sun->sun_path, sizeof(buf));
268 		} else {
269 			buf[0] = '@';
270 			strscpy(buf+1, sun->sun_path+1, sizeof(buf)-1);
271 		}
272 		xprt->address_strings[RPC_DISPLAY_ADDR] =
273 						kstrdup(buf, GFP_KERNEL);
274 		break;
275 	case AF_INET:
276 		(void)rpc_ntop(sap, buf, sizeof(buf));
277 		xprt->address_strings[RPC_DISPLAY_ADDR] =
278 						kstrdup(buf, GFP_KERNEL);
279 		sin = xs_addr_in(xprt);
280 		snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
281 		break;
282 	case AF_INET6:
283 		(void)rpc_ntop(sap, buf, sizeof(buf));
284 		xprt->address_strings[RPC_DISPLAY_ADDR] =
285 						kstrdup(buf, GFP_KERNEL);
286 		sin6 = xs_addr_in6(xprt);
287 		snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
288 		break;
289 	default:
290 		BUG();
291 	}
292 
293 	xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
294 }
295 
296 static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
297 {
298 	struct sockaddr *sap = xs_addr(xprt);
299 	char buf[128];
300 
301 	snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
302 	xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
303 
304 	snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
305 	xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
306 }
307 
308 static void xs_format_peer_addresses(struct rpc_xprt *xprt,
309 				     const char *protocol,
310 				     const char *netid)
311 {
312 	xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
313 	xprt->address_strings[RPC_DISPLAY_NETID] = netid;
314 	xs_format_common_peer_addresses(xprt);
315 	xs_format_common_peer_ports(xprt);
316 }
317 
318 static void xs_update_peer_port(struct rpc_xprt *xprt)
319 {
320 	kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
321 	kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
322 
323 	xs_format_common_peer_ports(xprt);
324 }
325 
326 static void xs_free_peer_addresses(struct rpc_xprt *xprt)
327 {
328 	unsigned int i;
329 
330 	for (i = 0; i < RPC_DISPLAY_MAX; i++)
331 		switch (i) {
332 		case RPC_DISPLAY_PROTO:
333 		case RPC_DISPLAY_NETID:
334 			continue;
335 		default:
336 			kfree(xprt->address_strings[i]);
337 		}
338 }
339 
340 static size_t
341 xs_alloc_sparse_pages(struct xdr_buf *buf, size_t want, gfp_t gfp)
342 {
343 	size_t i,n;
344 
345 	if (!want || !(buf->flags & XDRBUF_SPARSE_PAGES))
346 		return want;
347 	n = (buf->page_base + want + PAGE_SIZE - 1) >> PAGE_SHIFT;
348 	for (i = 0; i < n; i++) {
349 		if (buf->pages[i])
350 			continue;
351 		buf->bvec[i].bv_page = buf->pages[i] = alloc_page(gfp);
352 		if (!buf->pages[i]) {
353 			i *= PAGE_SIZE;
354 			return i > buf->page_base ? i - buf->page_base : 0;
355 		}
356 	}
357 	return want;
358 }
359 
360 static int
361 xs_sock_process_cmsg(struct socket *sock, struct msghdr *msg,
362 		     struct cmsghdr *cmsg, int ret)
363 {
364 	if (cmsg->cmsg_level == SOL_TLS &&
365 	    cmsg->cmsg_type == TLS_GET_RECORD_TYPE) {
366 		u8 content_type = *((u8 *)CMSG_DATA(cmsg));
367 
368 		switch (content_type) {
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 			ret = -ENOTCONN;
378 			break;
379 		default:
380 			ret = -EAGAIN;
381 		}
382 	}
383 	return ret;
384 }
385 
386 static int
387 xs_sock_recv_cmsg(struct socket *sock, struct msghdr *msg, int flags)
388 {
389 	union {
390 		struct cmsghdr	cmsg;
391 		u8		buf[CMSG_SPACE(sizeof(u8))];
392 	} u;
393 	int ret;
394 
395 	msg->msg_control = &u;
396 	msg->msg_controllen = sizeof(u);
397 	ret = sock_recvmsg(sock, msg, flags);
398 	if (msg->msg_controllen != sizeof(u))
399 		ret = xs_sock_process_cmsg(sock, msg, &u.cmsg, ret);
400 	return ret;
401 }
402 
403 static ssize_t
404 xs_sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags, size_t seek)
405 {
406 	ssize_t ret;
407 	if (seek != 0)
408 		iov_iter_advance(&msg->msg_iter, seek);
409 	ret = xs_sock_recv_cmsg(sock, msg, flags);
410 	return ret > 0 ? ret + seek : ret;
411 }
412 
413 static ssize_t
414 xs_read_kvec(struct socket *sock, struct msghdr *msg, int flags,
415 		struct kvec *kvec, size_t count, size_t seek)
416 {
417 	iov_iter_kvec(&msg->msg_iter, ITER_DEST, kvec, 1, count);
418 	return xs_sock_recvmsg(sock, msg, flags, seek);
419 }
420 
421 static ssize_t
422 xs_read_bvec(struct socket *sock, struct msghdr *msg, int flags,
423 		struct bio_vec *bvec, unsigned long nr, size_t count,
424 		size_t seek)
425 {
426 	iov_iter_bvec(&msg->msg_iter, ITER_DEST, bvec, nr, count);
427 	return xs_sock_recvmsg(sock, msg, flags, seek);
428 }
429 
430 static ssize_t
431 xs_read_discard(struct socket *sock, struct msghdr *msg, int flags,
432 		size_t count)
433 {
434 	iov_iter_discard(&msg->msg_iter, ITER_DEST, count);
435 	return xs_sock_recv_cmsg(sock, msg, flags);
436 }
437 
438 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
439 static void
440 xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
441 {
442 	struct bvec_iter bi = {
443 		.bi_size = count,
444 	};
445 	struct bio_vec bv;
446 
447 	bvec_iter_advance(bvec, &bi, seek & PAGE_MASK);
448 	for_each_bvec(bv, bvec, bi, bi)
449 		flush_dcache_page(bv.bv_page);
450 }
451 #else
452 static inline void
453 xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
454 {
455 }
456 #endif
457 
458 static ssize_t
459 xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags,
460 		struct xdr_buf *buf, size_t count, size_t seek, size_t *read)
461 {
462 	size_t want, seek_init = seek, offset = 0;
463 	ssize_t ret;
464 
465 	want = min_t(size_t, count, buf->head[0].iov_len);
466 	if (seek < want) {
467 		ret = xs_read_kvec(sock, msg, flags, &buf->head[0], want, seek);
468 		if (ret <= 0)
469 			goto sock_err;
470 		offset += ret;
471 		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
472 			goto out;
473 		if (ret != want)
474 			goto out;
475 		seek = 0;
476 	} else {
477 		seek -= want;
478 		offset += want;
479 	}
480 
481 	want = xs_alloc_sparse_pages(
482 		buf, min_t(size_t, count - offset, buf->page_len),
483 		GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
484 	if (seek < want) {
485 		ret = xs_read_bvec(sock, msg, flags, buf->bvec,
486 				xdr_buf_pagecount(buf),
487 				want + buf->page_base,
488 				seek + buf->page_base);
489 		if (ret <= 0)
490 			goto sock_err;
491 		xs_flush_bvec(buf->bvec, ret, seek + buf->page_base);
492 		ret -= buf->page_base;
493 		offset += ret;
494 		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
495 			goto out;
496 		if (ret != want)
497 			goto out;
498 		seek = 0;
499 	} else {
500 		seek -= want;
501 		offset += want;
502 	}
503 
504 	want = min_t(size_t, count - offset, buf->tail[0].iov_len);
505 	if (seek < want) {
506 		ret = xs_read_kvec(sock, msg, flags, &buf->tail[0], want, seek);
507 		if (ret <= 0)
508 			goto sock_err;
509 		offset += ret;
510 		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
511 			goto out;
512 		if (ret != want)
513 			goto out;
514 	} else if (offset < seek_init)
515 		offset = seek_init;
516 	ret = -EMSGSIZE;
517 out:
518 	*read = offset - seek_init;
519 	return ret;
520 sock_err:
521 	offset += seek;
522 	goto out;
523 }
524 
525 static void
526 xs_read_header(struct sock_xprt *transport, struct xdr_buf *buf)
527 {
528 	if (!transport->recv.copied) {
529 		if (buf->head[0].iov_len >= transport->recv.offset)
530 			memcpy(buf->head[0].iov_base,
531 					&transport->recv.xid,
532 					transport->recv.offset);
533 		transport->recv.copied = transport->recv.offset;
534 	}
535 }
536 
537 static bool
538 xs_read_stream_request_done(struct sock_xprt *transport)
539 {
540 	return transport->recv.fraghdr & cpu_to_be32(RPC_LAST_STREAM_FRAGMENT);
541 }
542 
543 static void
544 xs_read_stream_check_eor(struct sock_xprt *transport,
545 		struct msghdr *msg)
546 {
547 	if (xs_read_stream_request_done(transport))
548 		msg->msg_flags |= MSG_EOR;
549 }
550 
551 static ssize_t
552 xs_read_stream_request(struct sock_xprt *transport, struct msghdr *msg,
553 		int flags, struct rpc_rqst *req)
554 {
555 	struct xdr_buf *buf = &req->rq_private_buf;
556 	size_t want, read;
557 	ssize_t ret;
558 
559 	xs_read_header(transport, buf);
560 
561 	want = transport->recv.len - transport->recv.offset;
562 	if (want != 0) {
563 		ret = xs_read_xdr_buf(transport->sock, msg, flags, buf,
564 				transport->recv.copied + want,
565 				transport->recv.copied,
566 				&read);
567 		transport->recv.offset += read;
568 		transport->recv.copied += read;
569 	}
570 
571 	if (transport->recv.offset == transport->recv.len)
572 		xs_read_stream_check_eor(transport, msg);
573 
574 	if (want == 0)
575 		return 0;
576 
577 	switch (ret) {
578 	default:
579 		break;
580 	case -EFAULT:
581 	case -EMSGSIZE:
582 		msg->msg_flags |= MSG_TRUNC;
583 		return read;
584 	case 0:
585 		return -ESHUTDOWN;
586 	}
587 	return ret < 0 ? ret : read;
588 }
589 
590 static size_t
591 xs_read_stream_headersize(bool isfrag)
592 {
593 	if (isfrag)
594 		return sizeof(__be32);
595 	return 3 * sizeof(__be32);
596 }
597 
598 static ssize_t
599 xs_read_stream_header(struct sock_xprt *transport, struct msghdr *msg,
600 		int flags, size_t want, size_t seek)
601 {
602 	struct kvec kvec = {
603 		.iov_base = &transport->recv.fraghdr,
604 		.iov_len = want,
605 	};
606 	return xs_read_kvec(transport->sock, msg, flags, &kvec, want, seek);
607 }
608 
609 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
610 static ssize_t
611 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
612 {
613 	struct rpc_xprt *xprt = &transport->xprt;
614 	struct rpc_rqst *req;
615 	ssize_t ret;
616 
617 	/* Is this transport associated with the backchannel? */
618 	if (!xprt->bc_serv)
619 		return -ESHUTDOWN;
620 
621 	/* Look up and lock the request corresponding to the given XID */
622 	req = xprt_lookup_bc_request(xprt, transport->recv.xid);
623 	if (!req) {
624 		printk(KERN_WARNING "Callback slot table overflowed\n");
625 		return -ESHUTDOWN;
626 	}
627 	if (transport->recv.copied && !req->rq_private_buf.len)
628 		return -ESHUTDOWN;
629 
630 	ret = xs_read_stream_request(transport, msg, flags, req);
631 	if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
632 		xprt_complete_bc_request(req, transport->recv.copied);
633 	else
634 		req->rq_private_buf.len = transport->recv.copied;
635 
636 	return ret;
637 }
638 #else /* CONFIG_SUNRPC_BACKCHANNEL */
639 static ssize_t
640 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
641 {
642 	return -ESHUTDOWN;
643 }
644 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
645 
646 static ssize_t
647 xs_read_stream_reply(struct sock_xprt *transport, struct msghdr *msg, int flags)
648 {
649 	struct rpc_xprt *xprt = &transport->xprt;
650 	struct rpc_rqst *req;
651 	ssize_t ret = 0;
652 
653 	/* Look up and lock the request corresponding to the given XID */
654 	spin_lock(&xprt->queue_lock);
655 	req = xprt_lookup_rqst(xprt, transport->recv.xid);
656 	if (!req || (transport->recv.copied && !req->rq_private_buf.len)) {
657 		msg->msg_flags |= MSG_TRUNC;
658 		goto out;
659 	}
660 	xprt_pin_rqst(req);
661 	spin_unlock(&xprt->queue_lock);
662 
663 	ret = xs_read_stream_request(transport, msg, flags, req);
664 
665 	spin_lock(&xprt->queue_lock);
666 	if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
667 		xprt_complete_rqst(req->rq_task, transport->recv.copied);
668 	else
669 		req->rq_private_buf.len = transport->recv.copied;
670 	xprt_unpin_rqst(req);
671 out:
672 	spin_unlock(&xprt->queue_lock);
673 	return ret;
674 }
675 
676 static ssize_t
677 xs_read_stream(struct sock_xprt *transport, int flags)
678 {
679 	struct msghdr msg = { 0 };
680 	size_t want, read = 0;
681 	ssize_t ret = 0;
682 
683 	if (transport->recv.len == 0) {
684 		want = xs_read_stream_headersize(transport->recv.copied != 0);
685 		ret = xs_read_stream_header(transport, &msg, flags, want,
686 				transport->recv.offset);
687 		if (ret <= 0)
688 			goto out_err;
689 		transport->recv.offset = ret;
690 		if (transport->recv.offset != want)
691 			return transport->recv.offset;
692 		transport->recv.len = be32_to_cpu(transport->recv.fraghdr) &
693 			RPC_FRAGMENT_SIZE_MASK;
694 		transport->recv.offset -= sizeof(transport->recv.fraghdr);
695 		read = ret;
696 	}
697 
698 	switch (be32_to_cpu(transport->recv.calldir)) {
699 	default:
700 		msg.msg_flags |= MSG_TRUNC;
701 		break;
702 	case RPC_CALL:
703 		ret = xs_read_stream_call(transport, &msg, flags);
704 		break;
705 	case RPC_REPLY:
706 		ret = xs_read_stream_reply(transport, &msg, flags);
707 	}
708 	if (msg.msg_flags & MSG_TRUNC) {
709 		transport->recv.calldir = cpu_to_be32(-1);
710 		transport->recv.copied = -1;
711 	}
712 	if (ret < 0)
713 		goto out_err;
714 	read += ret;
715 	if (transport->recv.offset < transport->recv.len) {
716 		if (!(msg.msg_flags & MSG_TRUNC))
717 			return read;
718 		msg.msg_flags = 0;
719 		ret = xs_read_discard(transport->sock, &msg, flags,
720 				transport->recv.len - transport->recv.offset);
721 		if (ret <= 0)
722 			goto out_err;
723 		transport->recv.offset += ret;
724 		read += ret;
725 		if (transport->recv.offset != transport->recv.len)
726 			return read;
727 	}
728 	if (xs_read_stream_request_done(transport)) {
729 		trace_xs_stream_read_request(transport);
730 		transport->recv.copied = 0;
731 	}
732 	transport->recv.offset = 0;
733 	transport->recv.len = 0;
734 	return read;
735 out_err:
736 	return ret != 0 ? ret : -ESHUTDOWN;
737 }
738 
739 static __poll_t xs_poll_socket(struct sock_xprt *transport)
740 {
741 	return transport->sock->ops->poll(transport->file, transport->sock,
742 			NULL);
743 }
744 
745 static bool xs_poll_socket_readable(struct sock_xprt *transport)
746 {
747 	__poll_t events = xs_poll_socket(transport);
748 
749 	return (events & (EPOLLIN | EPOLLRDNORM)) && !(events & EPOLLRDHUP);
750 }
751 
752 static void xs_poll_check_readable(struct sock_xprt *transport)
753 {
754 
755 	clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
756 	if (test_bit(XPRT_SOCK_IGNORE_RECV, &transport->sock_state))
757 		return;
758 	if (!xs_poll_socket_readable(transport))
759 		return;
760 	if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
761 		queue_work(xprtiod_workqueue, &transport->recv_worker);
762 }
763 
764 static void xs_stream_data_receive(struct sock_xprt *transport)
765 {
766 	size_t read = 0;
767 	ssize_t ret = 0;
768 
769 	mutex_lock(&transport->recv_mutex);
770 	if (transport->sock == NULL)
771 		goto out;
772 	for (;;) {
773 		ret = xs_read_stream(transport, MSG_DONTWAIT);
774 		if (ret < 0)
775 			break;
776 		read += ret;
777 		cond_resched();
778 	}
779 	if (ret == -ESHUTDOWN)
780 		kernel_sock_shutdown(transport->sock, SHUT_RDWR);
781 	else
782 		xs_poll_check_readable(transport);
783 out:
784 	mutex_unlock(&transport->recv_mutex);
785 	trace_xs_stream_read_data(&transport->xprt, ret, read);
786 }
787 
788 static void xs_stream_data_receive_workfn(struct work_struct *work)
789 {
790 	struct sock_xprt *transport =
791 		container_of(work, struct sock_xprt, recv_worker);
792 	unsigned int pflags = memalloc_nofs_save();
793 
794 	xs_stream_data_receive(transport);
795 	memalloc_nofs_restore(pflags);
796 }
797 
798 static void
799 xs_stream_reset_connect(struct sock_xprt *transport)
800 {
801 	transport->recv.offset = 0;
802 	transport->recv.len = 0;
803 	transport->recv.copied = 0;
804 	transport->xmit.offset = 0;
805 }
806 
807 static void
808 xs_stream_start_connect(struct sock_xprt *transport)
809 {
810 	transport->xprt.stat.connect_count++;
811 	transport->xprt.stat.connect_start = jiffies;
812 }
813 
814 #define XS_SENDMSG_FLAGS	(MSG_DONTWAIT | MSG_NOSIGNAL)
815 
816 /**
817  * xs_nospace - handle transmit was incomplete
818  * @req: pointer to RPC request
819  * @transport: pointer to struct sock_xprt
820  *
821  */
822 static int xs_nospace(struct rpc_rqst *req, struct sock_xprt *transport)
823 {
824 	struct rpc_xprt *xprt = &transport->xprt;
825 	struct sock *sk = transport->inet;
826 	int ret = -EAGAIN;
827 
828 	trace_rpc_socket_nospace(req, transport);
829 
830 	/* Protect against races with write_space */
831 	spin_lock(&xprt->transport_lock);
832 
833 	/* Don't race with disconnect */
834 	if (xprt_connected(xprt)) {
835 		/* wait for more buffer space */
836 		set_bit(XPRT_SOCK_NOSPACE, &transport->sock_state);
837 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
838 		sk->sk_write_pending++;
839 		xprt_wait_for_buffer_space(xprt);
840 	} else
841 		ret = -ENOTCONN;
842 
843 	spin_unlock(&xprt->transport_lock);
844 	return ret;
845 }
846 
847 static int xs_sock_nospace(struct rpc_rqst *req)
848 {
849 	struct sock_xprt *transport =
850 		container_of(req->rq_xprt, struct sock_xprt, xprt);
851 	struct sock *sk = transport->inet;
852 	int ret = -EAGAIN;
853 
854 	lock_sock(sk);
855 	if (!sock_writeable(sk))
856 		ret = xs_nospace(req, transport);
857 	release_sock(sk);
858 	return ret;
859 }
860 
861 static int xs_stream_nospace(struct rpc_rqst *req, bool vm_wait)
862 {
863 	struct sock_xprt *transport =
864 		container_of(req->rq_xprt, struct sock_xprt, xprt);
865 	struct sock *sk = transport->inet;
866 	int ret = -EAGAIN;
867 
868 	if (vm_wait)
869 		return -ENOBUFS;
870 	lock_sock(sk);
871 	if (!sk_stream_memory_free(sk))
872 		ret = xs_nospace(req, transport);
873 	release_sock(sk);
874 	return ret;
875 }
876 
877 static int xs_stream_prepare_request(struct rpc_rqst *req, struct xdr_buf *buf)
878 {
879 	return xdr_alloc_bvec(buf, rpc_task_gfp_mask());
880 }
881 
882 /*
883  * Determine if the previous message in the stream was aborted before it
884  * could complete transmission.
885  */
886 static bool
887 xs_send_request_was_aborted(struct sock_xprt *transport, struct rpc_rqst *req)
888 {
889 	return transport->xmit.offset != 0 && req->rq_bytes_sent == 0;
890 }
891 
892 /*
893  * Return the stream record marker field for a record of length < 2^31-1
894  */
895 static rpc_fraghdr
896 xs_stream_record_marker(struct xdr_buf *xdr)
897 {
898 	if (!xdr->len)
899 		return 0;
900 	return cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | (u32)xdr->len);
901 }
902 
903 /**
904  * xs_local_send_request - write an RPC request to an AF_LOCAL socket
905  * @req: pointer to RPC request
906  *
907  * Return values:
908  *        0:	The request has been sent
909  *   EAGAIN:	The socket was blocked, please call again later to
910  *		complete the request
911  * ENOTCONN:	Caller needs to invoke connect logic then call again
912  *    other:	Some other error occurred, the request was not sent
913  */
914 static int xs_local_send_request(struct rpc_rqst *req)
915 {
916 	struct rpc_xprt *xprt = req->rq_xprt;
917 	struct sock_xprt *transport =
918 				container_of(xprt, struct sock_xprt, xprt);
919 	struct xdr_buf *xdr = &req->rq_snd_buf;
920 	rpc_fraghdr rm = xs_stream_record_marker(xdr);
921 	unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
922 	struct msghdr msg = {
923 		.msg_flags	= XS_SENDMSG_FLAGS,
924 	};
925 	bool vm_wait;
926 	unsigned int sent;
927 	int status;
928 
929 	/* Close the stream if the previous transmission was incomplete */
930 	if (xs_send_request_was_aborted(transport, req)) {
931 		xprt_force_disconnect(xprt);
932 		return -ENOTCONN;
933 	}
934 
935 	xs_pktdump("packet data:",
936 			req->rq_svec->iov_base, req->rq_svec->iov_len);
937 
938 	vm_wait = sk_stream_is_writeable(transport->inet) ? true : false;
939 
940 	req->rq_xtime = ktime_get();
941 	status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
942 				   transport->xmit.offset, rm, &sent);
943 	dprintk("RPC:       %s(%u) = %d\n",
944 			__func__, xdr->len - transport->xmit.offset, status);
945 
946 	if (likely(sent > 0) || status == 0) {
947 		transport->xmit.offset += sent;
948 		req->rq_bytes_sent = transport->xmit.offset;
949 		if (likely(req->rq_bytes_sent >= msglen)) {
950 			req->rq_xmit_bytes_sent += transport->xmit.offset;
951 			transport->xmit.offset = 0;
952 			return 0;
953 		}
954 		status = -EAGAIN;
955 		vm_wait = false;
956 	}
957 
958 	switch (status) {
959 	case -EAGAIN:
960 		status = xs_stream_nospace(req, vm_wait);
961 		break;
962 	default:
963 		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
964 			-status);
965 		fallthrough;
966 	case -EPIPE:
967 		xprt_force_disconnect(xprt);
968 		status = -ENOTCONN;
969 	}
970 
971 	return status;
972 }
973 
974 /**
975  * xs_udp_send_request - write an RPC request to a UDP socket
976  * @req: pointer to RPC request
977  *
978  * Return values:
979  *        0:	The request has been sent
980  *   EAGAIN:	The socket was blocked, please call again later to
981  *		complete the request
982  * ENOTCONN:	Caller needs to invoke connect logic then call again
983  *    other:	Some other error occurred, the request was not sent
984  */
985 static int xs_udp_send_request(struct rpc_rqst *req)
986 {
987 	struct rpc_xprt *xprt = req->rq_xprt;
988 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
989 	struct xdr_buf *xdr = &req->rq_snd_buf;
990 	struct msghdr msg = {
991 		.msg_name	= xs_addr(xprt),
992 		.msg_namelen	= xprt->addrlen,
993 		.msg_flags	= XS_SENDMSG_FLAGS,
994 	};
995 	unsigned int sent;
996 	int status;
997 
998 	xs_pktdump("packet data:",
999 				req->rq_svec->iov_base,
1000 				req->rq_svec->iov_len);
1001 
1002 	if (!xprt_bound(xprt))
1003 		return -ENOTCONN;
1004 
1005 	if (!xprt_request_get_cong(xprt, req))
1006 		return -EBADSLT;
1007 
1008 	status = xdr_alloc_bvec(xdr, rpc_task_gfp_mask());
1009 	if (status < 0)
1010 		return status;
1011 	req->rq_xtime = ktime_get();
1012 	status = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, 0, &sent);
1013 
1014 	dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
1015 			xdr->len, status);
1016 
1017 	/* firewall is blocking us, don't return -EAGAIN or we end up looping */
1018 	if (status == -EPERM)
1019 		goto process_status;
1020 
1021 	if (status == -EAGAIN && sock_writeable(transport->inet))
1022 		status = -ENOBUFS;
1023 
1024 	if (sent > 0 || status == 0) {
1025 		req->rq_xmit_bytes_sent += sent;
1026 		if (sent >= req->rq_slen)
1027 			return 0;
1028 		/* Still some bytes left; set up for a retry later. */
1029 		status = -EAGAIN;
1030 	}
1031 
1032 process_status:
1033 	switch (status) {
1034 	case -ENOTSOCK:
1035 		status = -ENOTCONN;
1036 		/* Should we call xs_close() here? */
1037 		break;
1038 	case -EAGAIN:
1039 		status = xs_sock_nospace(req);
1040 		break;
1041 	case -ENETUNREACH:
1042 	case -ENOBUFS:
1043 	case -EPIPE:
1044 	case -ECONNREFUSED:
1045 	case -EPERM:
1046 		/* When the server has died, an ICMP port unreachable message
1047 		 * prompts ECONNREFUSED. */
1048 		break;
1049 	default:
1050 		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1051 			-status);
1052 	}
1053 
1054 	return status;
1055 }
1056 
1057 /**
1058  * xs_tcp_send_request - write an RPC request to a TCP socket
1059  * @req: pointer to RPC request
1060  *
1061  * Return values:
1062  *        0:	The request has been sent
1063  *   EAGAIN:	The socket was blocked, please call again later to
1064  *		complete the request
1065  * ENOTCONN:	Caller needs to invoke connect logic then call again
1066  *    other:	Some other error occurred, the request was not sent
1067  *
1068  * XXX: In the case of soft timeouts, should we eventually give up
1069  *	if sendmsg is not able to make progress?
1070  */
1071 static int xs_tcp_send_request(struct rpc_rqst *req)
1072 {
1073 	struct rpc_xprt *xprt = req->rq_xprt;
1074 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1075 	struct xdr_buf *xdr = &req->rq_snd_buf;
1076 	rpc_fraghdr rm = xs_stream_record_marker(xdr);
1077 	unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
1078 	struct msghdr msg = {
1079 		.msg_flags	= XS_SENDMSG_FLAGS,
1080 	};
1081 	bool vm_wait;
1082 	unsigned int sent;
1083 	int status;
1084 
1085 	/* Close the stream if the previous transmission was incomplete */
1086 	if (xs_send_request_was_aborted(transport, req)) {
1087 		if (transport->sock != NULL)
1088 			kernel_sock_shutdown(transport->sock, SHUT_RDWR);
1089 		return -ENOTCONN;
1090 	}
1091 	if (!transport->inet)
1092 		return -ENOTCONN;
1093 
1094 	xs_pktdump("packet data:",
1095 				req->rq_svec->iov_base,
1096 				req->rq_svec->iov_len);
1097 
1098 	if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state))
1099 		xs_tcp_set_socket_timeouts(xprt, transport->sock);
1100 
1101 	xs_set_srcport(transport, transport->sock);
1102 
1103 	/* Continue transmitting the packet/record. We must be careful
1104 	 * to cope with writespace callbacks arriving _after_ we have
1105 	 * called sendmsg(). */
1106 	req->rq_xtime = ktime_get();
1107 	tcp_sock_set_cork(transport->inet, true);
1108 
1109 	vm_wait = sk_stream_is_writeable(transport->inet) ? true : false;
1110 
1111 	do {
1112 		status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
1113 					   transport->xmit.offset, rm, &sent);
1114 
1115 		dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
1116 				xdr->len - transport->xmit.offset, status);
1117 
1118 		/* If we've sent the entire packet, immediately
1119 		 * reset the count of bytes sent. */
1120 		transport->xmit.offset += sent;
1121 		req->rq_bytes_sent = transport->xmit.offset;
1122 		if (likely(req->rq_bytes_sent >= msglen)) {
1123 			req->rq_xmit_bytes_sent += transport->xmit.offset;
1124 			transport->xmit.offset = 0;
1125 			if (atomic_long_read(&xprt->xmit_queuelen) == 1)
1126 				tcp_sock_set_cork(transport->inet, false);
1127 			return 0;
1128 		}
1129 
1130 		WARN_ON_ONCE(sent == 0 && status == 0);
1131 
1132 		if (sent > 0)
1133 			vm_wait = false;
1134 
1135 	} while (status == 0);
1136 
1137 	switch (status) {
1138 	case -ENOTSOCK:
1139 		status = -ENOTCONN;
1140 		/* Should we call xs_close() here? */
1141 		break;
1142 	case -EAGAIN:
1143 		status = xs_stream_nospace(req, vm_wait);
1144 		break;
1145 	case -ECONNRESET:
1146 	case -ECONNREFUSED:
1147 	case -ENOTCONN:
1148 	case -EADDRINUSE:
1149 	case -ENOBUFS:
1150 	case -EPIPE:
1151 		break;
1152 	default:
1153 		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1154 			-status);
1155 	}
1156 
1157 	return status;
1158 }
1159 
1160 static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1161 {
1162 	transport->old_data_ready = sk->sk_data_ready;
1163 	transport->old_state_change = sk->sk_state_change;
1164 	transport->old_write_space = sk->sk_write_space;
1165 	transport->old_error_report = sk->sk_error_report;
1166 }
1167 
1168 static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1169 {
1170 	sk->sk_data_ready = transport->old_data_ready;
1171 	sk->sk_state_change = transport->old_state_change;
1172 	sk->sk_write_space = transport->old_write_space;
1173 	sk->sk_error_report = transport->old_error_report;
1174 }
1175 
1176 static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
1177 {
1178 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1179 
1180 	clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1181 	clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state);
1182 	clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state);
1183 	clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state);
1184 	clear_bit(XPRT_SOCK_NOSPACE, &transport->sock_state);
1185 }
1186 
1187 static void xs_run_error_worker(struct sock_xprt *transport, unsigned int nr)
1188 {
1189 	set_bit(nr, &transport->sock_state);
1190 	queue_work(xprtiod_workqueue, &transport->error_worker);
1191 }
1192 
1193 static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
1194 {
1195 	xprt->connect_cookie++;
1196 	smp_mb__before_atomic();
1197 	clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1198 	clear_bit(XPRT_CLOSING, &xprt->state);
1199 	xs_sock_reset_state_flags(xprt);
1200 	smp_mb__after_atomic();
1201 }
1202 
1203 /**
1204  * xs_error_report - callback to handle TCP socket state errors
1205  * @sk: socket
1206  *
1207  * Note: we don't call sock_error() since there may be a rpc_task
1208  * using the socket, and so we don't want to clear sk->sk_err.
1209  */
1210 static void xs_error_report(struct sock *sk)
1211 {
1212 	struct sock_xprt *transport;
1213 	struct rpc_xprt *xprt;
1214 
1215 	if (!(xprt = xprt_from_sock(sk)))
1216 		return;
1217 
1218 	transport = container_of(xprt, struct sock_xprt, xprt);
1219 	transport->xprt_err = -sk->sk_err;
1220 	if (transport->xprt_err == 0)
1221 		return;
1222 	dprintk("RPC:       xs_error_report client %p, error=%d...\n",
1223 			xprt, -transport->xprt_err);
1224 	trace_rpc_socket_error(xprt, sk->sk_socket, transport->xprt_err);
1225 
1226 	/* barrier ensures xprt_err is set before XPRT_SOCK_WAKE_ERROR */
1227 	smp_mb__before_atomic();
1228 	xs_run_error_worker(transport, XPRT_SOCK_WAKE_ERROR);
1229 }
1230 
1231 static void xs_reset_transport(struct sock_xprt *transport)
1232 {
1233 	struct socket *sock = transport->sock;
1234 	struct sock *sk = transport->inet;
1235 	struct rpc_xprt *xprt = &transport->xprt;
1236 	struct file *filp = transport->file;
1237 
1238 	if (sk == NULL)
1239 		return;
1240 	/*
1241 	 * Make sure we're calling this in a context from which it is safe
1242 	 * to call __fput_sync(). In practice that means rpciod and the
1243 	 * system workqueue.
1244 	 */
1245 	if (!(current->flags & PF_WQ_WORKER)) {
1246 		WARN_ON_ONCE(1);
1247 		set_bit(XPRT_CLOSE_WAIT, &xprt->state);
1248 		return;
1249 	}
1250 
1251 	if (atomic_read(&transport->xprt.swapper))
1252 		sk_clear_memalloc(sk);
1253 
1254 	tls_handshake_cancel(sk);
1255 
1256 	kernel_sock_shutdown(sock, SHUT_RDWR);
1257 
1258 	mutex_lock(&transport->recv_mutex);
1259 	lock_sock(sk);
1260 	transport->inet = NULL;
1261 	transport->sock = NULL;
1262 	transport->file = NULL;
1263 
1264 	sk->sk_user_data = NULL;
1265 
1266 	xs_restore_old_callbacks(transport, sk);
1267 	xprt_clear_connected(xprt);
1268 	xs_sock_reset_connection_flags(xprt);
1269 	/* Reset stream record info */
1270 	xs_stream_reset_connect(transport);
1271 	release_sock(sk);
1272 	mutex_unlock(&transport->recv_mutex);
1273 
1274 	trace_rpc_socket_close(xprt, sock);
1275 	__fput_sync(filp);
1276 
1277 	xprt_disconnect_done(xprt);
1278 }
1279 
1280 /**
1281  * xs_close - close a socket
1282  * @xprt: transport
1283  *
1284  * This is used when all requests are complete; ie, no DRC state remains
1285  * on the server we want to save.
1286  *
1287  * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
1288  * xs_reset_transport() zeroing the socket from underneath a writer.
1289  */
1290 static void xs_close(struct rpc_xprt *xprt)
1291 {
1292 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1293 
1294 	dprintk("RPC:       xs_close xprt %p\n", xprt);
1295 
1296 	xs_reset_transport(transport);
1297 	xprt->reestablish_timeout = 0;
1298 }
1299 
1300 static void xs_inject_disconnect(struct rpc_xprt *xprt)
1301 {
1302 	dprintk("RPC:       injecting transport disconnect on xprt=%p\n",
1303 		xprt);
1304 	xprt_disconnect_done(xprt);
1305 }
1306 
1307 static void xs_xprt_free(struct rpc_xprt *xprt)
1308 {
1309 	xs_free_peer_addresses(xprt);
1310 	xprt_free(xprt);
1311 }
1312 
1313 /**
1314  * xs_destroy - prepare to shutdown a transport
1315  * @xprt: doomed transport
1316  *
1317  */
1318 static void xs_destroy(struct rpc_xprt *xprt)
1319 {
1320 	struct sock_xprt *transport = container_of(xprt,
1321 			struct sock_xprt, xprt);
1322 	dprintk("RPC:       xs_destroy xprt %p\n", xprt);
1323 
1324 	cancel_delayed_work_sync(&transport->connect_worker);
1325 	xs_close(xprt);
1326 	cancel_work_sync(&transport->recv_worker);
1327 	cancel_work_sync(&transport->error_worker);
1328 	xs_xprt_free(xprt);
1329 	module_put(THIS_MODULE);
1330 }
1331 
1332 /**
1333  * xs_udp_data_read_skb - receive callback for UDP sockets
1334  * @xprt: transport
1335  * @sk: socket
1336  * @skb: skbuff
1337  *
1338  */
1339 static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
1340 		struct sock *sk,
1341 		struct sk_buff *skb)
1342 {
1343 	struct rpc_task *task;
1344 	struct rpc_rqst *rovr;
1345 	int repsize, copied;
1346 	u32 _xid;
1347 	__be32 *xp;
1348 
1349 	repsize = skb->len;
1350 	if (repsize < 4) {
1351 		dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
1352 		return;
1353 	}
1354 
1355 	/* Copy the XID from the skb... */
1356 	xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
1357 	if (xp == NULL)
1358 		return;
1359 
1360 	/* Look up and lock the request corresponding to the given XID */
1361 	spin_lock(&xprt->queue_lock);
1362 	rovr = xprt_lookup_rqst(xprt, *xp);
1363 	if (!rovr)
1364 		goto out_unlock;
1365 	xprt_pin_rqst(rovr);
1366 	xprt_update_rtt(rovr->rq_task);
1367 	spin_unlock(&xprt->queue_lock);
1368 	task = rovr->rq_task;
1369 
1370 	if ((copied = rovr->rq_private_buf.buflen) > repsize)
1371 		copied = repsize;
1372 
1373 	/* Suck it into the iovec, verify checksum if not done by hw. */
1374 	if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1375 		spin_lock(&xprt->queue_lock);
1376 		__UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
1377 		goto out_unpin;
1378 	}
1379 
1380 
1381 	spin_lock(&xprt->transport_lock);
1382 	xprt_adjust_cwnd(xprt, task, copied);
1383 	spin_unlock(&xprt->transport_lock);
1384 	spin_lock(&xprt->queue_lock);
1385 	xprt_complete_rqst(task, copied);
1386 	__UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
1387 out_unpin:
1388 	xprt_unpin_rqst(rovr);
1389  out_unlock:
1390 	spin_unlock(&xprt->queue_lock);
1391 }
1392 
1393 static void xs_udp_data_receive(struct sock_xprt *transport)
1394 {
1395 	struct sk_buff *skb;
1396 	struct sock *sk;
1397 	int err;
1398 
1399 	mutex_lock(&transport->recv_mutex);
1400 	sk = transport->inet;
1401 	if (sk == NULL)
1402 		goto out;
1403 	for (;;) {
1404 		skb = skb_recv_udp(sk, MSG_DONTWAIT, &err);
1405 		if (skb == NULL)
1406 			break;
1407 		xs_udp_data_read_skb(&transport->xprt, sk, skb);
1408 		consume_skb(skb);
1409 		cond_resched();
1410 	}
1411 	xs_poll_check_readable(transport);
1412 out:
1413 	mutex_unlock(&transport->recv_mutex);
1414 }
1415 
1416 static void xs_udp_data_receive_workfn(struct work_struct *work)
1417 {
1418 	struct sock_xprt *transport =
1419 		container_of(work, struct sock_xprt, recv_worker);
1420 	unsigned int pflags = memalloc_nofs_save();
1421 
1422 	xs_udp_data_receive(transport);
1423 	memalloc_nofs_restore(pflags);
1424 }
1425 
1426 /**
1427  * xs_data_ready - "data ready" callback for sockets
1428  * @sk: socket with data to read
1429  *
1430  */
1431 static void xs_data_ready(struct sock *sk)
1432 {
1433 	struct rpc_xprt *xprt;
1434 
1435 	trace_sk_data_ready(sk);
1436 
1437 	xprt = xprt_from_sock(sk);
1438 	if (xprt != NULL) {
1439 		struct sock_xprt *transport = container_of(xprt,
1440 				struct sock_xprt, xprt);
1441 
1442 		trace_xs_data_ready(xprt);
1443 
1444 		transport->old_data_ready(sk);
1445 
1446 		if (test_bit(XPRT_SOCK_IGNORE_RECV, &transport->sock_state))
1447 			return;
1448 
1449 		/* Any data means we had a useful conversation, so
1450 		 * then we don't need to delay the next reconnect
1451 		 */
1452 		if (xprt->reestablish_timeout)
1453 			xprt->reestablish_timeout = 0;
1454 		if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1455 			queue_work(xprtiod_workqueue, &transport->recv_worker);
1456 	}
1457 }
1458 
1459 /*
1460  * Helper function to force a TCP close if the server is sending
1461  * junk and/or it has put us in CLOSE_WAIT
1462  */
1463 static void xs_tcp_force_close(struct rpc_xprt *xprt)
1464 {
1465 	xprt_force_disconnect(xprt);
1466 }
1467 
1468 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1469 static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
1470 {
1471 	return PAGE_SIZE;
1472 }
1473 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1474 
1475 /**
1476  * xs_local_state_change - callback to handle AF_LOCAL socket state changes
1477  * @sk: socket whose state has changed
1478  *
1479  */
1480 static void xs_local_state_change(struct sock *sk)
1481 {
1482 	struct rpc_xprt *xprt;
1483 	struct sock_xprt *transport;
1484 
1485 	if (!(xprt = xprt_from_sock(sk)))
1486 		return;
1487 	transport = container_of(xprt, struct sock_xprt, xprt);
1488 	if (sk->sk_shutdown & SHUTDOWN_MASK) {
1489 		clear_bit(XPRT_CONNECTED, &xprt->state);
1490 		/* Trigger the socket release */
1491 		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1492 	}
1493 }
1494 
1495 /**
1496  * xs_tcp_state_change - callback to handle TCP socket state changes
1497  * @sk: socket whose state has changed
1498  *
1499  */
1500 static void xs_tcp_state_change(struct sock *sk)
1501 {
1502 	struct rpc_xprt *xprt;
1503 	struct sock_xprt *transport;
1504 
1505 	if (!(xprt = xprt_from_sock(sk)))
1506 		return;
1507 	dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1508 	dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1509 			sk->sk_state, xprt_connected(xprt),
1510 			sock_flag(sk, SOCK_DEAD),
1511 			sock_flag(sk, SOCK_ZAPPED),
1512 			sk->sk_shutdown);
1513 
1514 	transport = container_of(xprt, struct sock_xprt, xprt);
1515 	trace_rpc_socket_state_change(xprt, sk->sk_socket);
1516 	switch (sk->sk_state) {
1517 	case TCP_ESTABLISHED:
1518 		if (!xprt_test_and_set_connected(xprt)) {
1519 			xprt->connect_cookie++;
1520 			clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
1521 			xprt_clear_connecting(xprt);
1522 
1523 			xprt->stat.connect_count++;
1524 			xprt->stat.connect_time += (long)jiffies -
1525 						   xprt->stat.connect_start;
1526 			xs_run_error_worker(transport, XPRT_SOCK_WAKE_PENDING);
1527 		}
1528 		break;
1529 	case TCP_FIN_WAIT1:
1530 		/* The client initiated a shutdown of the socket */
1531 		xprt->connect_cookie++;
1532 		xprt->reestablish_timeout = 0;
1533 		set_bit(XPRT_CLOSING, &xprt->state);
1534 		smp_mb__before_atomic();
1535 		clear_bit(XPRT_CONNECTED, &xprt->state);
1536 		clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1537 		smp_mb__after_atomic();
1538 		break;
1539 	case TCP_CLOSE_WAIT:
1540 		/* The server initiated a shutdown of the socket */
1541 		xprt->connect_cookie++;
1542 		clear_bit(XPRT_CONNECTED, &xprt->state);
1543 		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1544 		fallthrough;
1545 	case TCP_CLOSING:
1546 		/*
1547 		 * If the server closed down the connection, make sure that
1548 		 * we back off before reconnecting
1549 		 */
1550 		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1551 			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1552 		break;
1553 	case TCP_LAST_ACK:
1554 		set_bit(XPRT_CLOSING, &xprt->state);
1555 		smp_mb__before_atomic();
1556 		clear_bit(XPRT_CONNECTED, &xprt->state);
1557 		smp_mb__after_atomic();
1558 		break;
1559 	case TCP_CLOSE:
1560 		if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
1561 					&transport->sock_state))
1562 			xprt_clear_connecting(xprt);
1563 		clear_bit(XPRT_CLOSING, &xprt->state);
1564 		/* Trigger the socket release */
1565 		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1566 	}
1567 }
1568 
1569 static void xs_write_space(struct sock *sk)
1570 {
1571 	struct sock_xprt *transport;
1572 	struct rpc_xprt *xprt;
1573 
1574 	if (!sk->sk_socket)
1575 		return;
1576 	clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1577 
1578 	if (unlikely(!(xprt = xprt_from_sock(sk))))
1579 		return;
1580 	transport = container_of(xprt, struct sock_xprt, xprt);
1581 	if (!test_and_clear_bit(XPRT_SOCK_NOSPACE, &transport->sock_state))
1582 		return;
1583 	xs_run_error_worker(transport, XPRT_SOCK_WAKE_WRITE);
1584 	sk->sk_write_pending--;
1585 }
1586 
1587 /**
1588  * xs_udp_write_space - callback invoked when socket buffer space
1589  *                             becomes available
1590  * @sk: socket whose state has changed
1591  *
1592  * Called when more output buffer space is available for this socket.
1593  * We try not to wake our writers until they can make "significant"
1594  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1595  * with a bunch of small requests.
1596  */
1597 static void xs_udp_write_space(struct sock *sk)
1598 {
1599 	/* from net/core/sock.c:sock_def_write_space */
1600 	if (sock_writeable(sk))
1601 		xs_write_space(sk);
1602 }
1603 
1604 /**
1605  * xs_tcp_write_space - callback invoked when socket buffer space
1606  *                             becomes available
1607  * @sk: socket whose state has changed
1608  *
1609  * Called when more output buffer space is available for this socket.
1610  * We try not to wake our writers until they can make "significant"
1611  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1612  * with a bunch of small requests.
1613  */
1614 static void xs_tcp_write_space(struct sock *sk)
1615 {
1616 	/* from net/core/stream.c:sk_stream_write_space */
1617 	if (sk_stream_is_writeable(sk))
1618 		xs_write_space(sk);
1619 }
1620 
1621 static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1622 {
1623 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1624 	struct sock *sk = transport->inet;
1625 
1626 	if (transport->rcvsize) {
1627 		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1628 		sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1629 	}
1630 	if (transport->sndsize) {
1631 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1632 		sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1633 		sk->sk_write_space(sk);
1634 	}
1635 }
1636 
1637 /**
1638  * xs_udp_set_buffer_size - set send and receive limits
1639  * @xprt: generic transport
1640  * @sndsize: requested size of send buffer, in bytes
1641  * @rcvsize: requested size of receive buffer, in bytes
1642  *
1643  * Set socket send and receive buffer size limits.
1644  */
1645 static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1646 {
1647 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1648 
1649 	transport->sndsize = 0;
1650 	if (sndsize)
1651 		transport->sndsize = sndsize + 1024;
1652 	transport->rcvsize = 0;
1653 	if (rcvsize)
1654 		transport->rcvsize = rcvsize + 1024;
1655 
1656 	xs_udp_do_set_buffer_size(xprt);
1657 }
1658 
1659 /**
1660  * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1661  * @xprt: controlling transport
1662  * @task: task that timed out
1663  *
1664  * Adjust the congestion window after a retransmit timeout has occurred.
1665  */
1666 static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1667 {
1668 	spin_lock(&xprt->transport_lock);
1669 	xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1670 	spin_unlock(&xprt->transport_lock);
1671 }
1672 
1673 static int xs_get_random_port(void)
1674 {
1675 	unsigned short min = xprt_min_resvport, max = xprt_max_resvport;
1676 	unsigned short range;
1677 	unsigned short rand;
1678 
1679 	if (max < min)
1680 		return -EADDRINUSE;
1681 	range = max - min + 1;
1682 	rand = get_random_u32_below(range);
1683 	return rand + min;
1684 }
1685 
1686 static unsigned short xs_sock_getport(struct socket *sock)
1687 {
1688 	struct sockaddr_storage buf;
1689 	unsigned short port = 0;
1690 
1691 	if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0)
1692 		goto out;
1693 	switch (buf.ss_family) {
1694 	case AF_INET6:
1695 		port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1696 		break;
1697 	case AF_INET:
1698 		port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1699 	}
1700 out:
1701 	return port;
1702 }
1703 
1704 /**
1705  * xs_set_port - reset the port number in the remote endpoint address
1706  * @xprt: generic transport
1707  * @port: new port number
1708  *
1709  */
1710 static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1711 {
1712 	dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1713 
1714 	rpc_set_port(xs_addr(xprt), port);
1715 	xs_update_peer_port(xprt);
1716 }
1717 
1718 static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1719 {
1720 	if (transport->srcport == 0 && transport->xprt.reuseport)
1721 		transport->srcport = xs_sock_getport(sock);
1722 }
1723 
1724 static int xs_get_srcport(struct sock_xprt *transport)
1725 {
1726 	int port = transport->srcport;
1727 
1728 	if (port == 0 && transport->xprt.resvport)
1729 		port = xs_get_random_port();
1730 	return port;
1731 }
1732 
1733 static unsigned short xs_sock_srcport(struct rpc_xprt *xprt)
1734 {
1735 	struct sock_xprt *sock = container_of(xprt, struct sock_xprt, xprt);
1736 	unsigned short ret = 0;
1737 	mutex_lock(&sock->recv_mutex);
1738 	if (sock->sock)
1739 		ret = xs_sock_getport(sock->sock);
1740 	mutex_unlock(&sock->recv_mutex);
1741 	return ret;
1742 }
1743 
1744 static int xs_sock_srcaddr(struct rpc_xprt *xprt, char *buf, size_t buflen)
1745 {
1746 	struct sock_xprt *sock = container_of(xprt, struct sock_xprt, xprt);
1747 	union {
1748 		struct sockaddr sa;
1749 		struct sockaddr_storage st;
1750 	} saddr;
1751 	int ret = -ENOTCONN;
1752 
1753 	mutex_lock(&sock->recv_mutex);
1754 	if (sock->sock) {
1755 		ret = kernel_getsockname(sock->sock, &saddr.sa);
1756 		if (ret >= 0)
1757 			ret = snprintf(buf, buflen, "%pISc", &saddr.sa);
1758 	}
1759 	mutex_unlock(&sock->recv_mutex);
1760 	return ret;
1761 }
1762 
1763 static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1764 {
1765 	if (transport->srcport != 0)
1766 		transport->srcport = 0;
1767 	if (!transport->xprt.resvport)
1768 		return 0;
1769 	if (port <= xprt_min_resvport || port > xprt_max_resvport)
1770 		return xprt_max_resvport;
1771 	return --port;
1772 }
1773 static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1774 {
1775 	struct sockaddr_storage myaddr;
1776 	int err, nloop = 0;
1777 	int port = xs_get_srcport(transport);
1778 	unsigned short last;
1779 
1780 	/*
1781 	 * If we are asking for any ephemeral port (i.e. port == 0 &&
1782 	 * transport->xprt.resvport == 0), don't bind.  Let the local
1783 	 * port selection happen implicitly when the socket is used
1784 	 * (for example at connect time).
1785 	 *
1786 	 * This ensures that we can continue to establish TCP
1787 	 * connections even when all local ephemeral ports are already
1788 	 * a part of some TCP connection.  This makes no difference
1789 	 * for UDP sockets, but also doesn't harm them.
1790 	 *
1791 	 * If we're asking for any reserved port (i.e. port == 0 &&
1792 	 * transport->xprt.resvport == 1) xs_get_srcport above will
1793 	 * ensure that port is non-zero and we will bind as needed.
1794 	 */
1795 	if (port <= 0)
1796 		return port;
1797 
1798 	memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1799 	do {
1800 		rpc_set_port((struct sockaddr *)&myaddr, port);
1801 		err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1802 				transport->xprt.addrlen);
1803 		if (err == 0) {
1804 			if (transport->xprt.reuseport)
1805 				transport->srcport = port;
1806 			break;
1807 		}
1808 		last = port;
1809 		port = xs_next_srcport(transport, port);
1810 		if (port > last)
1811 			nloop++;
1812 	} while (err == -EADDRINUSE && nloop != 2);
1813 
1814 	if (myaddr.ss_family == AF_INET)
1815 		dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1816 				&((struct sockaddr_in *)&myaddr)->sin_addr,
1817 				port, err ? "failed" : "ok", err);
1818 	else
1819 		dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1820 				&((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1821 				port, err ? "failed" : "ok", err);
1822 	return err;
1823 }
1824 
1825 /*
1826  * We don't support autobind on AF_LOCAL sockets
1827  */
1828 static void xs_local_rpcbind(struct rpc_task *task)
1829 {
1830 	xprt_set_bound(task->tk_xprt);
1831 }
1832 
1833 static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1834 {
1835 }
1836 
1837 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1838 static struct lock_class_key xs_key[3];
1839 static struct lock_class_key xs_slock_key[3];
1840 
1841 static inline void xs_reclassify_socketu(struct socket *sock)
1842 {
1843 	struct sock *sk = sock->sk;
1844 
1845 	sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1846 		&xs_slock_key[0], "sk_lock-AF_LOCAL-RPC", &xs_key[0]);
1847 }
1848 
1849 static inline void xs_reclassify_socket4(struct socket *sock)
1850 {
1851 	struct sock *sk = sock->sk;
1852 
1853 	sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1854 		&xs_slock_key[1], "sk_lock-AF_INET-RPC", &xs_key[1]);
1855 }
1856 
1857 static inline void xs_reclassify_socket6(struct socket *sock)
1858 {
1859 	struct sock *sk = sock->sk;
1860 
1861 	sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1862 		&xs_slock_key[2], "sk_lock-AF_INET6-RPC", &xs_key[2]);
1863 }
1864 
1865 static inline void xs_reclassify_socket(int family, struct socket *sock)
1866 {
1867 	if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
1868 		return;
1869 
1870 	switch (family) {
1871 	case AF_LOCAL:
1872 		xs_reclassify_socketu(sock);
1873 		break;
1874 	case AF_INET:
1875 		xs_reclassify_socket4(sock);
1876 		break;
1877 	case AF_INET6:
1878 		xs_reclassify_socket6(sock);
1879 		break;
1880 	}
1881 }
1882 #else
1883 static inline void xs_reclassify_socket(int family, struct socket *sock)
1884 {
1885 }
1886 #endif
1887 
1888 static void xs_dummy_setup_socket(struct work_struct *work)
1889 {
1890 }
1891 
1892 static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1893 		struct sock_xprt *transport, int family, int type,
1894 		int protocol, bool reuseport)
1895 {
1896 	struct file *filp;
1897 	struct socket *sock;
1898 	int err;
1899 
1900 	err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1901 	if (err < 0) {
1902 		dprintk("RPC:       can't create %d transport socket (%d).\n",
1903 				protocol, -err);
1904 		goto out;
1905 	}
1906 	xs_reclassify_socket(family, sock);
1907 
1908 	if (reuseport)
1909 		sock_set_reuseport(sock->sk);
1910 
1911 	err = xs_bind(transport, sock);
1912 	if (err) {
1913 		sock_release(sock);
1914 		goto out;
1915 	}
1916 
1917 	filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1918 	if (IS_ERR(filp))
1919 		return ERR_CAST(filp);
1920 	transport->file = filp;
1921 
1922 	return sock;
1923 out:
1924 	return ERR_PTR(err);
1925 }
1926 
1927 static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1928 				      struct socket *sock)
1929 {
1930 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1931 									xprt);
1932 
1933 	if (!transport->inet) {
1934 		struct sock *sk = sock->sk;
1935 
1936 		lock_sock(sk);
1937 
1938 		xs_save_old_callbacks(transport, sk);
1939 
1940 		sk->sk_user_data = xprt;
1941 		sk->sk_data_ready = xs_data_ready;
1942 		sk->sk_write_space = xs_udp_write_space;
1943 		sk->sk_state_change = xs_local_state_change;
1944 		sk->sk_error_report = xs_error_report;
1945 		sk->sk_use_task_frag = false;
1946 
1947 		xprt_clear_connected(xprt);
1948 
1949 		/* Reset to new socket */
1950 		transport->sock = sock;
1951 		transport->inet = sk;
1952 
1953 		release_sock(sk);
1954 	}
1955 
1956 	xs_stream_start_connect(transport);
1957 
1958 	return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1959 }
1960 
1961 /**
1962  * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1963  * @transport: socket transport to connect
1964  */
1965 static int xs_local_setup_socket(struct sock_xprt *transport)
1966 {
1967 	struct rpc_xprt *xprt = &transport->xprt;
1968 	struct file *filp;
1969 	struct socket *sock;
1970 	int status;
1971 
1972 	status = __sock_create(xprt->xprt_net, AF_LOCAL,
1973 					SOCK_STREAM, 0, &sock, 1);
1974 	if (status < 0) {
1975 		dprintk("RPC:       can't create AF_LOCAL "
1976 			"transport socket (%d).\n", -status);
1977 		goto out;
1978 	}
1979 	xs_reclassify_socket(AF_LOCAL, sock);
1980 
1981 	filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1982 	if (IS_ERR(filp)) {
1983 		status = PTR_ERR(filp);
1984 		goto out;
1985 	}
1986 	transport->file = filp;
1987 
1988 	dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
1989 			xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1990 
1991 	status = xs_local_finish_connecting(xprt, sock);
1992 	trace_rpc_socket_connect(xprt, sock, status);
1993 	switch (status) {
1994 	case 0:
1995 		dprintk("RPC:       xprt %p connected to %s\n",
1996 				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1997 		xprt->stat.connect_count++;
1998 		xprt->stat.connect_time += (long)jiffies -
1999 					   xprt->stat.connect_start;
2000 		xprt_set_connected(xprt);
2001 		break;
2002 	case -ENOBUFS:
2003 		break;
2004 	case -ENOENT:
2005 		dprintk("RPC:       xprt %p: socket %s does not exist\n",
2006 				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2007 		break;
2008 	case -ECONNREFUSED:
2009 		dprintk("RPC:       xprt %p: connection refused for %s\n",
2010 				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2011 		break;
2012 	default:
2013 		printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
2014 				__func__, -status,
2015 				xprt->address_strings[RPC_DISPLAY_ADDR]);
2016 	}
2017 
2018 out:
2019 	xprt_clear_connecting(xprt);
2020 	xprt_wake_pending_tasks(xprt, status);
2021 	return status;
2022 }
2023 
2024 static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2025 {
2026 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2027 	int ret;
2028 
2029 	if (transport->file)
2030 		goto force_disconnect;
2031 
2032 	if (RPC_IS_ASYNC(task)) {
2033 		/*
2034 		 * We want the AF_LOCAL connect to be resolved in the
2035 		 * filesystem namespace of the process making the rpc
2036 		 * call.  Thus we connect synchronously.
2037 		 *
2038 		 * If we want to support asynchronous AF_LOCAL calls,
2039 		 * we'll need to figure out how to pass a namespace to
2040 		 * connect.
2041 		 */
2042 		rpc_task_set_rpc_status(task, -ENOTCONN);
2043 		goto out_wake;
2044 	}
2045 	ret = xs_local_setup_socket(transport);
2046 	if (ret && !RPC_IS_SOFTCONN(task))
2047 		msleep_interruptible(15000);
2048 	return;
2049 force_disconnect:
2050 	xprt_force_disconnect(xprt);
2051 out_wake:
2052 	xprt_clear_connecting(xprt);
2053 	xprt_wake_pending_tasks(xprt, -ENOTCONN);
2054 }
2055 
2056 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
2057 /*
2058  * Note that this should be called with XPRT_LOCKED held, or recv_mutex
2059  * held, or when we otherwise know that we have exclusive access to the
2060  * socket, to guard against races with xs_reset_transport.
2061  */
2062 static void xs_set_memalloc(struct rpc_xprt *xprt)
2063 {
2064 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
2065 			xprt);
2066 
2067 	/*
2068 	 * If there's no sock, then we have nothing to set. The
2069 	 * reconnecting process will get it for us.
2070 	 */
2071 	if (!transport->inet)
2072 		return;
2073 	if (atomic_read(&xprt->swapper))
2074 		sk_set_memalloc(transport->inet);
2075 }
2076 
2077 /**
2078  * xs_enable_swap - Tag this transport as being used for swap.
2079  * @xprt: transport to tag
2080  *
2081  * Take a reference to this transport on behalf of the rpc_clnt, and
2082  * optionally mark it for swapping if it wasn't already.
2083  */
2084 static int
2085 xs_enable_swap(struct rpc_xprt *xprt)
2086 {
2087 	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2088 
2089 	mutex_lock(&xs->recv_mutex);
2090 	if (atomic_inc_return(&xprt->swapper) == 1 &&
2091 	    xs->inet)
2092 		sk_set_memalloc(xs->inet);
2093 	mutex_unlock(&xs->recv_mutex);
2094 	return 0;
2095 }
2096 
2097 /**
2098  * xs_disable_swap - Untag this transport as being used for swap.
2099  * @xprt: transport to tag
2100  *
2101  * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
2102  * swapper refcount goes to 0, untag the socket as a memalloc socket.
2103  */
2104 static void
2105 xs_disable_swap(struct rpc_xprt *xprt)
2106 {
2107 	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2108 
2109 	mutex_lock(&xs->recv_mutex);
2110 	if (atomic_dec_and_test(&xprt->swapper) &&
2111 	    xs->inet)
2112 		sk_clear_memalloc(xs->inet);
2113 	mutex_unlock(&xs->recv_mutex);
2114 }
2115 #else
2116 static void xs_set_memalloc(struct rpc_xprt *xprt)
2117 {
2118 }
2119 
2120 static int
2121 xs_enable_swap(struct rpc_xprt *xprt)
2122 {
2123 	return -EINVAL;
2124 }
2125 
2126 static void
2127 xs_disable_swap(struct rpc_xprt *xprt)
2128 {
2129 }
2130 #endif
2131 
2132 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2133 {
2134 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2135 
2136 	if (!transport->inet) {
2137 		struct sock *sk = sock->sk;
2138 
2139 		lock_sock(sk);
2140 
2141 		xs_save_old_callbacks(transport, sk);
2142 
2143 		sk->sk_user_data = xprt;
2144 		sk->sk_data_ready = xs_data_ready;
2145 		sk->sk_write_space = xs_udp_write_space;
2146 		sk->sk_use_task_frag = false;
2147 
2148 		xprt_set_connected(xprt);
2149 
2150 		/* Reset to new socket */
2151 		transport->sock = sock;
2152 		transport->inet = sk;
2153 
2154 		xs_set_memalloc(xprt);
2155 
2156 		release_sock(sk);
2157 	}
2158 	xs_udp_do_set_buffer_size(xprt);
2159 
2160 	xprt->stat.connect_start = jiffies;
2161 }
2162 
2163 static void xs_udp_setup_socket(struct work_struct *work)
2164 {
2165 	struct sock_xprt *transport =
2166 		container_of(work, struct sock_xprt, connect_worker.work);
2167 	struct rpc_xprt *xprt = &transport->xprt;
2168 	struct socket *sock;
2169 	int status = -EIO;
2170 	unsigned int pflags = current->flags;
2171 
2172 	if (atomic_read(&xprt->swapper))
2173 		current->flags |= PF_MEMALLOC;
2174 	sock = xs_create_sock(xprt, transport,
2175 			xs_addr(xprt)->sa_family, SOCK_DGRAM,
2176 			IPPROTO_UDP, false);
2177 	if (IS_ERR(sock))
2178 		goto out;
2179 
2180 	dprintk("RPC:       worker connecting xprt %p via %s to "
2181 				"%s (port %s)\n", xprt,
2182 			xprt->address_strings[RPC_DISPLAY_PROTO],
2183 			xprt->address_strings[RPC_DISPLAY_ADDR],
2184 			xprt->address_strings[RPC_DISPLAY_PORT]);
2185 
2186 	xs_udp_finish_connecting(xprt, sock);
2187 	trace_rpc_socket_connect(xprt, sock, 0);
2188 	status = 0;
2189 out:
2190 	xprt_clear_connecting(xprt);
2191 	xprt_unlock_connect(xprt, transport);
2192 	xprt_wake_pending_tasks(xprt, status);
2193 	current_restore_flags(pflags, PF_MEMALLOC);
2194 }
2195 
2196 /**
2197  * xs_tcp_shutdown - gracefully shut down a TCP socket
2198  * @xprt: transport
2199  *
2200  * Initiates a graceful shutdown of the TCP socket by calling the
2201  * equivalent of shutdown(SHUT_RDWR);
2202  */
2203 static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2204 {
2205 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2206 	struct socket *sock = transport->sock;
2207 	int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
2208 
2209 	if (sock == NULL)
2210 		return;
2211 	if (!xprt->reuseport) {
2212 		xs_close(xprt);
2213 		return;
2214 	}
2215 	switch (skst) {
2216 	case TCP_FIN_WAIT1:
2217 	case TCP_FIN_WAIT2:
2218 	case TCP_LAST_ACK:
2219 		break;
2220 	case TCP_ESTABLISHED:
2221 	case TCP_CLOSE_WAIT:
2222 		kernel_sock_shutdown(sock, SHUT_RDWR);
2223 		trace_rpc_socket_shutdown(xprt, sock);
2224 		break;
2225 	default:
2226 		xs_reset_transport(transport);
2227 	}
2228 }
2229 
2230 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
2231 		struct socket *sock)
2232 {
2233 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2234 	unsigned int keepidle;
2235 	unsigned int keepcnt;
2236 	unsigned int timeo;
2237 
2238 	spin_lock(&xprt->transport_lock);
2239 	keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
2240 	keepcnt = xprt->timeout->to_retries + 1;
2241 	timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2242 		(xprt->timeout->to_retries + 1);
2243 	clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2244 	spin_unlock(&xprt->transport_lock);
2245 
2246 	/* TCP Keepalive options */
2247 	sock_set_keepalive(sock->sk);
2248 	tcp_sock_set_keepidle(sock->sk, keepidle);
2249 	tcp_sock_set_keepintvl(sock->sk, keepidle);
2250 	tcp_sock_set_keepcnt(sock->sk, keepcnt);
2251 
2252 	/* TCP user timeout (see RFC5482) */
2253 	tcp_sock_set_user_timeout(sock->sk, timeo);
2254 }
2255 
2256 static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
2257 		unsigned long connect_timeout,
2258 		unsigned long reconnect_timeout)
2259 {
2260 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2261 	struct rpc_timeout to;
2262 	unsigned long initval;
2263 
2264 	spin_lock(&xprt->transport_lock);
2265 	if (reconnect_timeout < xprt->max_reconnect_timeout)
2266 		xprt->max_reconnect_timeout = reconnect_timeout;
2267 	if (connect_timeout < xprt->connect_timeout) {
2268 		memcpy(&to, xprt->timeout, sizeof(to));
2269 		initval = DIV_ROUND_UP(connect_timeout, to.to_retries + 1);
2270 		/* Arbitrary lower limit */
2271 		if (initval <  XS_TCP_INIT_REEST_TO << 1)
2272 			initval = XS_TCP_INIT_REEST_TO << 1;
2273 		to.to_initval = initval;
2274 		to.to_maxval = initval;
2275 		memcpy(&transport->tcp_timeout, &to,
2276 				sizeof(transport->tcp_timeout));
2277 		xprt->timeout = &transport->tcp_timeout;
2278 		xprt->connect_timeout = connect_timeout;
2279 	}
2280 	set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2281 	spin_unlock(&xprt->transport_lock);
2282 }
2283 
2284 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2285 {
2286 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2287 
2288 	if (!transport->inet) {
2289 		struct sock *sk = sock->sk;
2290 
2291 		/* Avoid temporary address, they are bad for long-lived
2292 		 * connections such as NFS mounts.
2293 		 * RFC4941, section 3.6 suggests that:
2294 		 *    Individual applications, which have specific
2295 		 *    knowledge about the normal duration of connections,
2296 		 *    MAY override this as appropriate.
2297 		 */
2298 		if (xs_addr(xprt)->sa_family == PF_INET6) {
2299 			ip6_sock_set_addr_preferences(sk,
2300 				IPV6_PREFER_SRC_PUBLIC);
2301 		}
2302 
2303 		xs_tcp_set_socket_timeouts(xprt, sock);
2304 		tcp_sock_set_nodelay(sk);
2305 
2306 		lock_sock(sk);
2307 
2308 		xs_save_old_callbacks(transport, sk);
2309 
2310 		sk->sk_user_data = xprt;
2311 		sk->sk_data_ready = xs_data_ready;
2312 		sk->sk_state_change = xs_tcp_state_change;
2313 		sk->sk_write_space = xs_tcp_write_space;
2314 		sk->sk_error_report = xs_error_report;
2315 		sk->sk_use_task_frag = false;
2316 
2317 		/* socket options */
2318 		sock_reset_flag(sk, SOCK_LINGER);
2319 
2320 		xprt_clear_connected(xprt);
2321 
2322 		/* Reset to new socket */
2323 		transport->sock = sock;
2324 		transport->inet = sk;
2325 
2326 		release_sock(sk);
2327 	}
2328 
2329 	if (!xprt_bound(xprt))
2330 		return -ENOTCONN;
2331 
2332 	xs_set_memalloc(xprt);
2333 
2334 	xs_stream_start_connect(transport);
2335 
2336 	/* Tell the socket layer to start connecting... */
2337 	set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2338 	return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2339 }
2340 
2341 /**
2342  * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2343  * @work: queued work item
2344  *
2345  * Invoked by a work queue tasklet.
2346  */
2347 static void xs_tcp_setup_socket(struct work_struct *work)
2348 {
2349 	struct sock_xprt *transport =
2350 		container_of(work, struct sock_xprt, connect_worker.work);
2351 	struct socket *sock = transport->sock;
2352 	struct rpc_xprt *xprt = &transport->xprt;
2353 	int status;
2354 	unsigned int pflags = current->flags;
2355 
2356 	if (atomic_read(&xprt->swapper))
2357 		current->flags |= PF_MEMALLOC;
2358 
2359 	if (xprt_connected(xprt))
2360 		goto out;
2361 	if (test_and_clear_bit(XPRT_SOCK_CONNECT_SENT,
2362 			       &transport->sock_state) ||
2363 	    !sock) {
2364 		xs_reset_transport(transport);
2365 		sock = xs_create_sock(xprt, transport, xs_addr(xprt)->sa_family,
2366 				      SOCK_STREAM, IPPROTO_TCP, true);
2367 		if (IS_ERR(sock)) {
2368 			xprt_wake_pending_tasks(xprt, PTR_ERR(sock));
2369 			goto out;
2370 		}
2371 	}
2372 
2373 	dprintk("RPC:       worker connecting xprt %p via %s to "
2374 				"%s (port %s)\n", xprt,
2375 			xprt->address_strings[RPC_DISPLAY_PROTO],
2376 			xprt->address_strings[RPC_DISPLAY_ADDR],
2377 			xprt->address_strings[RPC_DISPLAY_PORT]);
2378 
2379 	status = xs_tcp_finish_connecting(xprt, sock);
2380 	trace_rpc_socket_connect(xprt, sock, status);
2381 	dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2382 			xprt, -status, xprt_connected(xprt),
2383 			sock->sk->sk_state);
2384 	switch (status) {
2385 	case 0:
2386 	case -EINPROGRESS:
2387 		/* SYN_SENT! */
2388 		set_bit(XPRT_SOCK_CONNECT_SENT, &transport->sock_state);
2389 		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2390 			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2391 		fallthrough;
2392 	case -EALREADY:
2393 		goto out_unlock;
2394 	case -EADDRNOTAVAIL:
2395 		/* Source port number is unavailable. Try a new one! */
2396 		transport->srcport = 0;
2397 		status = -EAGAIN;
2398 		break;
2399 	case -EINVAL:
2400 		/* Happens, for instance, if the user specified a link
2401 		 * local IPv6 address without a scope-id.
2402 		 */
2403 	case -ECONNREFUSED:
2404 	case -ECONNRESET:
2405 	case -ENETDOWN:
2406 	case -ENETUNREACH:
2407 	case -EHOSTUNREACH:
2408 	case -EADDRINUSE:
2409 	case -ENOBUFS:
2410 		break;
2411 	default:
2412 		printk("%s: connect returned unhandled error %d\n",
2413 			__func__, status);
2414 		status = -EAGAIN;
2415 	}
2416 
2417 	/* xs_tcp_force_close() wakes tasks with a fixed error code.
2418 	 * We need to wake them first to ensure the correct error code.
2419 	 */
2420 	xprt_wake_pending_tasks(xprt, status);
2421 	xs_tcp_force_close(xprt);
2422 out:
2423 	xprt_clear_connecting(xprt);
2424 out_unlock:
2425 	xprt_unlock_connect(xprt, transport);
2426 	current_restore_flags(pflags, PF_MEMALLOC);
2427 }
2428 
2429 /*
2430  * Transfer the connected socket to @upper_transport, then mark that
2431  * xprt CONNECTED.
2432  */
2433 static int xs_tcp_tls_finish_connecting(struct rpc_xprt *lower_xprt,
2434 					struct sock_xprt *upper_transport)
2435 {
2436 	struct sock_xprt *lower_transport =
2437 			container_of(lower_xprt, struct sock_xprt, xprt);
2438 	struct rpc_xprt *upper_xprt = &upper_transport->xprt;
2439 
2440 	if (!upper_transport->inet) {
2441 		struct socket *sock = lower_transport->sock;
2442 		struct sock *sk = sock->sk;
2443 
2444 		/* Avoid temporary address, they are bad for long-lived
2445 		 * connections such as NFS mounts.
2446 		 * RFC4941, section 3.6 suggests that:
2447 		 *    Individual applications, which have specific
2448 		 *    knowledge about the normal duration of connections,
2449 		 *    MAY override this as appropriate.
2450 		 */
2451 		if (xs_addr(upper_xprt)->sa_family == PF_INET6)
2452 			ip6_sock_set_addr_preferences(sk, IPV6_PREFER_SRC_PUBLIC);
2453 
2454 		xs_tcp_set_socket_timeouts(upper_xprt, sock);
2455 		tcp_sock_set_nodelay(sk);
2456 
2457 		lock_sock(sk);
2458 
2459 		/* @sk is already connected, so it now has the RPC callbacks.
2460 		 * Reach into @lower_transport to save the original ones.
2461 		 */
2462 		upper_transport->old_data_ready = lower_transport->old_data_ready;
2463 		upper_transport->old_state_change = lower_transport->old_state_change;
2464 		upper_transport->old_write_space = lower_transport->old_write_space;
2465 		upper_transport->old_error_report = lower_transport->old_error_report;
2466 		sk->sk_user_data = upper_xprt;
2467 
2468 		/* socket options */
2469 		sock_reset_flag(sk, SOCK_LINGER);
2470 
2471 		xprt_clear_connected(upper_xprt);
2472 
2473 		upper_transport->sock = sock;
2474 		upper_transport->inet = sk;
2475 		upper_transport->file = lower_transport->file;
2476 
2477 		release_sock(sk);
2478 
2479 		/* Reset lower_transport before shutting down its clnt */
2480 		mutex_lock(&lower_transport->recv_mutex);
2481 		lower_transport->inet = NULL;
2482 		lower_transport->sock = NULL;
2483 		lower_transport->file = NULL;
2484 
2485 		xprt_clear_connected(lower_xprt);
2486 		xs_sock_reset_connection_flags(lower_xprt);
2487 		xs_stream_reset_connect(lower_transport);
2488 		mutex_unlock(&lower_transport->recv_mutex);
2489 	}
2490 
2491 	if (!xprt_bound(upper_xprt))
2492 		return -ENOTCONN;
2493 
2494 	xs_set_memalloc(upper_xprt);
2495 
2496 	if (!xprt_test_and_set_connected(upper_xprt)) {
2497 		upper_xprt->connect_cookie++;
2498 		clear_bit(XPRT_SOCK_CONNECTING, &upper_transport->sock_state);
2499 		xprt_clear_connecting(upper_xprt);
2500 
2501 		upper_xprt->stat.connect_count++;
2502 		upper_xprt->stat.connect_time += (long)jiffies -
2503 					   upper_xprt->stat.connect_start;
2504 		xs_run_error_worker(upper_transport, XPRT_SOCK_WAKE_PENDING);
2505 	}
2506 	return 0;
2507 }
2508 
2509 /**
2510  * xs_tls_handshake_done - TLS handshake completion handler
2511  * @data: address of xprt to wake
2512  * @status: status of handshake
2513  * @peerid: serial number of key containing the remote's identity
2514  *
2515  */
2516 static void xs_tls_handshake_done(void *data, int status, key_serial_t peerid)
2517 {
2518 	struct rpc_xprt *lower_xprt = data;
2519 	struct sock_xprt *lower_transport =
2520 				container_of(lower_xprt, struct sock_xprt, xprt);
2521 
2522 	lower_transport->xprt_err = status ? -EACCES : 0;
2523 	complete(&lower_transport->handshake_done);
2524 	xprt_put(lower_xprt);
2525 }
2526 
2527 static int xs_tls_handshake_sync(struct rpc_xprt *lower_xprt, struct xprtsec_parms *xprtsec)
2528 {
2529 	struct sock_xprt *lower_transport =
2530 				container_of(lower_xprt, struct sock_xprt, xprt);
2531 	struct tls_handshake_args args = {
2532 		.ta_sock	= lower_transport->sock,
2533 		.ta_done	= xs_tls_handshake_done,
2534 		.ta_data	= xprt_get(lower_xprt),
2535 		.ta_peername	= lower_xprt->servername,
2536 	};
2537 	struct sock *sk = lower_transport->inet;
2538 	int rc;
2539 
2540 	init_completion(&lower_transport->handshake_done);
2541 	set_bit(XPRT_SOCK_IGNORE_RECV, &lower_transport->sock_state);
2542 	lower_transport->xprt_err = -ETIMEDOUT;
2543 	switch (xprtsec->policy) {
2544 	case RPC_XPRTSEC_TLS_ANON:
2545 		rc = tls_client_hello_anon(&args, GFP_KERNEL);
2546 		if (rc)
2547 			goto out_put_xprt;
2548 		break;
2549 	case RPC_XPRTSEC_TLS_X509:
2550 		args.ta_my_cert = xprtsec->cert_serial;
2551 		args.ta_my_privkey = xprtsec->privkey_serial;
2552 		rc = tls_client_hello_x509(&args, GFP_KERNEL);
2553 		if (rc)
2554 			goto out_put_xprt;
2555 		break;
2556 	default:
2557 		rc = -EACCES;
2558 		goto out_put_xprt;
2559 	}
2560 
2561 	rc = wait_for_completion_interruptible_timeout(&lower_transport->handshake_done,
2562 						       XS_TLS_HANDSHAKE_TO);
2563 	if (rc <= 0) {
2564 		if (!tls_handshake_cancel(sk)) {
2565 			if (rc == 0)
2566 				rc = -ETIMEDOUT;
2567 			goto out_put_xprt;
2568 		}
2569 	}
2570 
2571 	rc = lower_transport->xprt_err;
2572 
2573 out:
2574 	xs_stream_reset_connect(lower_transport);
2575 	clear_bit(XPRT_SOCK_IGNORE_RECV, &lower_transport->sock_state);
2576 	return rc;
2577 
2578 out_put_xprt:
2579 	xprt_put(lower_xprt);
2580 	goto out;
2581 }
2582 
2583 /**
2584  * xs_tcp_tls_setup_socket - establish a TLS session on a TCP socket
2585  * @work: queued work item
2586  *
2587  * Invoked by a work queue tasklet.
2588  *
2589  * For RPC-with-TLS, there is a two-stage connection process.
2590  *
2591  * The "upper-layer xprt" is visible to the RPC consumer. Once it has
2592  * been marked connected, the consumer knows that a TCP connection and
2593  * a TLS session have been established.
2594  *
2595  * A "lower-layer xprt", created in this function, handles the mechanics
2596  * of connecting the TCP socket, performing the RPC_AUTH_TLS probe, and
2597  * then driving the TLS handshake. Once all that is complete, the upper
2598  * layer xprt is marked connected.
2599  */
2600 static void xs_tcp_tls_setup_socket(struct work_struct *work)
2601 {
2602 	struct sock_xprt *upper_transport =
2603 		container_of(work, struct sock_xprt, connect_worker.work);
2604 	struct rpc_clnt *upper_clnt = upper_transport->clnt;
2605 	struct rpc_xprt *upper_xprt = &upper_transport->xprt;
2606 	struct rpc_create_args args = {
2607 		.net		= upper_xprt->xprt_net,
2608 		.protocol	= upper_xprt->prot,
2609 		.address	= (struct sockaddr *)&upper_xprt->addr,
2610 		.addrsize	= upper_xprt->addrlen,
2611 		.timeout	= upper_clnt->cl_timeout,
2612 		.servername	= upper_xprt->servername,
2613 		.program	= upper_clnt->cl_program,
2614 		.prognumber	= upper_clnt->cl_prog,
2615 		.version	= upper_clnt->cl_vers,
2616 		.authflavor	= RPC_AUTH_TLS,
2617 		.cred		= upper_clnt->cl_cred,
2618 		.xprtsec	= {
2619 			.policy		= RPC_XPRTSEC_NONE,
2620 		},
2621 	};
2622 	unsigned int pflags = current->flags;
2623 	struct rpc_clnt *lower_clnt;
2624 	struct rpc_xprt *lower_xprt;
2625 	int status;
2626 
2627 	if (atomic_read(&upper_xprt->swapper))
2628 		current->flags |= PF_MEMALLOC;
2629 
2630 	xs_stream_start_connect(upper_transport);
2631 
2632 	/* This implicitly sends an RPC_AUTH_TLS probe */
2633 	lower_clnt = rpc_create(&args);
2634 	if (IS_ERR(lower_clnt)) {
2635 		trace_rpc_tls_unavailable(upper_clnt, upper_xprt);
2636 		clear_bit(XPRT_SOCK_CONNECTING, &upper_transport->sock_state);
2637 		xprt_clear_connecting(upper_xprt);
2638 		xprt_wake_pending_tasks(upper_xprt, PTR_ERR(lower_clnt));
2639 		xs_run_error_worker(upper_transport, XPRT_SOCK_WAKE_PENDING);
2640 		goto out_unlock;
2641 	}
2642 
2643 	/* RPC_AUTH_TLS probe was successful. Try a TLS handshake on
2644 	 * the lower xprt.
2645 	 */
2646 	rcu_read_lock();
2647 	lower_xprt = rcu_dereference(lower_clnt->cl_xprt);
2648 	rcu_read_unlock();
2649 	status = xs_tls_handshake_sync(lower_xprt, &upper_xprt->xprtsec);
2650 	if (status) {
2651 		trace_rpc_tls_not_started(upper_clnt, upper_xprt);
2652 		goto out_close;
2653 	}
2654 
2655 	status = xs_tcp_tls_finish_connecting(lower_xprt, upper_transport);
2656 	if (status)
2657 		goto out_close;
2658 
2659 	trace_rpc_socket_connect(upper_xprt, upper_transport->sock, 0);
2660 	if (!xprt_test_and_set_connected(upper_xprt)) {
2661 		upper_xprt->connect_cookie++;
2662 		clear_bit(XPRT_SOCK_CONNECTING, &upper_transport->sock_state);
2663 		xprt_clear_connecting(upper_xprt);
2664 
2665 		upper_xprt->stat.connect_count++;
2666 		upper_xprt->stat.connect_time += (long)jiffies -
2667 					   upper_xprt->stat.connect_start;
2668 		xs_run_error_worker(upper_transport, XPRT_SOCK_WAKE_PENDING);
2669 	}
2670 	rpc_shutdown_client(lower_clnt);
2671 
2672 out_unlock:
2673 	current_restore_flags(pflags, PF_MEMALLOC);
2674 	upper_transport->clnt = NULL;
2675 	xprt_unlock_connect(upper_xprt, upper_transport);
2676 	return;
2677 
2678 out_close:
2679 	rpc_shutdown_client(lower_clnt);
2680 
2681 	/* xprt_force_disconnect() wakes tasks with a fixed tk_status code.
2682 	 * Wake them first here to ensure they get our tk_status code.
2683 	 */
2684 	xprt_wake_pending_tasks(upper_xprt, status);
2685 	xs_tcp_force_close(upper_xprt);
2686 	xprt_clear_connecting(upper_xprt);
2687 	goto out_unlock;
2688 }
2689 
2690 /**
2691  * xs_connect - connect a socket to a remote endpoint
2692  * @xprt: pointer to transport structure
2693  * @task: address of RPC task that manages state of connect request
2694  *
2695  * TCP: If the remote end dropped the connection, delay reconnecting.
2696  *
2697  * UDP socket connects are synchronous, but we use a work queue anyway
2698  * to guarantee that even unprivileged user processes can set up a
2699  * socket on a privileged port.
2700  *
2701  * If a UDP socket connect fails, the delay behavior here prevents
2702  * retry floods (hard mounts).
2703  */
2704 static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2705 {
2706 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2707 	unsigned long delay = 0;
2708 
2709 	WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2710 
2711 	if (transport->sock != NULL) {
2712 		dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2713 			"seconds\n", xprt, xprt->reestablish_timeout / HZ);
2714 
2715 		delay = xprt_reconnect_delay(xprt);
2716 		xprt_reconnect_backoff(xprt, XS_TCP_INIT_REEST_TO);
2717 
2718 	} else
2719 		dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2720 
2721 	transport->clnt = task->tk_client;
2722 	queue_delayed_work(xprtiod_workqueue,
2723 			&transport->connect_worker,
2724 			delay);
2725 }
2726 
2727 static void xs_wake_disconnect(struct sock_xprt *transport)
2728 {
2729 	if (test_and_clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state))
2730 		xs_tcp_force_close(&transport->xprt);
2731 }
2732 
2733 static void xs_wake_write(struct sock_xprt *transport)
2734 {
2735 	if (test_and_clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state))
2736 		xprt_write_space(&transport->xprt);
2737 }
2738 
2739 static void xs_wake_error(struct sock_xprt *transport)
2740 {
2741 	int sockerr;
2742 
2743 	if (!test_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2744 		return;
2745 	mutex_lock(&transport->recv_mutex);
2746 	if (transport->sock == NULL)
2747 		goto out;
2748 	if (!test_and_clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2749 		goto out;
2750 	sockerr = xchg(&transport->xprt_err, 0);
2751 	if (sockerr < 0)
2752 		xprt_wake_pending_tasks(&transport->xprt, sockerr);
2753 out:
2754 	mutex_unlock(&transport->recv_mutex);
2755 }
2756 
2757 static void xs_wake_pending(struct sock_xprt *transport)
2758 {
2759 	if (test_and_clear_bit(XPRT_SOCK_WAKE_PENDING, &transport->sock_state))
2760 		xprt_wake_pending_tasks(&transport->xprt, -EAGAIN);
2761 }
2762 
2763 static void xs_error_handle(struct work_struct *work)
2764 {
2765 	struct sock_xprt *transport = container_of(work,
2766 			struct sock_xprt, error_worker);
2767 
2768 	xs_wake_disconnect(transport);
2769 	xs_wake_write(transport);
2770 	xs_wake_error(transport);
2771 	xs_wake_pending(transport);
2772 }
2773 
2774 /**
2775  * xs_local_print_stats - display AF_LOCAL socket-specific stats
2776  * @xprt: rpc_xprt struct containing statistics
2777  * @seq: output file
2778  *
2779  */
2780 static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2781 {
2782 	long idle_time = 0;
2783 
2784 	if (xprt_connected(xprt))
2785 		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2786 
2787 	seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2788 			"%llu %llu %lu %llu %llu\n",
2789 			xprt->stat.bind_count,
2790 			xprt->stat.connect_count,
2791 			xprt->stat.connect_time / HZ,
2792 			idle_time,
2793 			xprt->stat.sends,
2794 			xprt->stat.recvs,
2795 			xprt->stat.bad_xids,
2796 			xprt->stat.req_u,
2797 			xprt->stat.bklog_u,
2798 			xprt->stat.max_slots,
2799 			xprt->stat.sending_u,
2800 			xprt->stat.pending_u);
2801 }
2802 
2803 /**
2804  * xs_udp_print_stats - display UDP socket-specific stats
2805  * @xprt: rpc_xprt struct containing statistics
2806  * @seq: output file
2807  *
2808  */
2809 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2810 {
2811 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2812 
2813 	seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2814 			"%lu %llu %llu\n",
2815 			transport->srcport,
2816 			xprt->stat.bind_count,
2817 			xprt->stat.sends,
2818 			xprt->stat.recvs,
2819 			xprt->stat.bad_xids,
2820 			xprt->stat.req_u,
2821 			xprt->stat.bklog_u,
2822 			xprt->stat.max_slots,
2823 			xprt->stat.sending_u,
2824 			xprt->stat.pending_u);
2825 }
2826 
2827 /**
2828  * xs_tcp_print_stats - display TCP socket-specific stats
2829  * @xprt: rpc_xprt struct containing statistics
2830  * @seq: output file
2831  *
2832  */
2833 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2834 {
2835 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2836 	long idle_time = 0;
2837 
2838 	if (xprt_connected(xprt))
2839 		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2840 
2841 	seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2842 			"%llu %llu %lu %llu %llu\n",
2843 			transport->srcport,
2844 			xprt->stat.bind_count,
2845 			xprt->stat.connect_count,
2846 			xprt->stat.connect_time / HZ,
2847 			idle_time,
2848 			xprt->stat.sends,
2849 			xprt->stat.recvs,
2850 			xprt->stat.bad_xids,
2851 			xprt->stat.req_u,
2852 			xprt->stat.bklog_u,
2853 			xprt->stat.max_slots,
2854 			xprt->stat.sending_u,
2855 			xprt->stat.pending_u);
2856 }
2857 
2858 /*
2859  * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2860  * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2861  * to use the server side send routines.
2862  */
2863 static int bc_malloc(struct rpc_task *task)
2864 {
2865 	struct rpc_rqst *rqst = task->tk_rqstp;
2866 	size_t size = rqst->rq_callsize;
2867 	struct page *page;
2868 	struct rpc_buffer *buf;
2869 
2870 	if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2871 		WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2872 			  size);
2873 		return -EINVAL;
2874 	}
2875 
2876 	page = alloc_page(GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
2877 	if (!page)
2878 		return -ENOMEM;
2879 
2880 	buf = page_address(page);
2881 	buf->len = PAGE_SIZE;
2882 
2883 	rqst->rq_buffer = buf->data;
2884 	rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2885 	return 0;
2886 }
2887 
2888 /*
2889  * Free the space allocated in the bc_alloc routine
2890  */
2891 static void bc_free(struct rpc_task *task)
2892 {
2893 	void *buffer = task->tk_rqstp->rq_buffer;
2894 	struct rpc_buffer *buf;
2895 
2896 	buf = container_of(buffer, struct rpc_buffer, data);
2897 	free_page((unsigned long)buf);
2898 }
2899 
2900 static int bc_sendto(struct rpc_rqst *req)
2901 {
2902 	struct xdr_buf *xdr = &req->rq_snd_buf;
2903 	struct sock_xprt *transport =
2904 			container_of(req->rq_xprt, struct sock_xprt, xprt);
2905 	struct msghdr msg = {
2906 		.msg_flags	= 0,
2907 	};
2908 	rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT |
2909 					 (u32)xdr->len);
2910 	unsigned int sent = 0;
2911 	int err;
2912 
2913 	req->rq_xtime = ktime_get();
2914 	err = xdr_alloc_bvec(xdr, rpc_task_gfp_mask());
2915 	if (err < 0)
2916 		return err;
2917 	err = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, marker, &sent);
2918 	xdr_free_bvec(xdr);
2919 	if (err < 0 || sent != (xdr->len + sizeof(marker)))
2920 		return -EAGAIN;
2921 	return sent;
2922 }
2923 
2924 /**
2925  * bc_send_request - Send a backchannel Call on a TCP socket
2926  * @req: rpc_rqst containing Call message to be sent
2927  *
2928  * xpt_mutex ensures @rqstp's whole message is written to the socket
2929  * without interruption.
2930  *
2931  * Return values:
2932  *   %0 if the message was sent successfully
2933  *   %ENOTCONN if the message was not sent
2934  */
2935 static int bc_send_request(struct rpc_rqst *req)
2936 {
2937 	struct svc_xprt	*xprt;
2938 	int len;
2939 
2940 	/*
2941 	 * Get the server socket associated with this callback xprt
2942 	 */
2943 	xprt = req->rq_xprt->bc_xprt;
2944 
2945 	/*
2946 	 * Grab the mutex to serialize data as the connection is shared
2947 	 * with the fore channel
2948 	 */
2949 	mutex_lock(&xprt->xpt_mutex);
2950 	if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2951 		len = -ENOTCONN;
2952 	else
2953 		len = bc_sendto(req);
2954 	mutex_unlock(&xprt->xpt_mutex);
2955 
2956 	if (len > 0)
2957 		len = 0;
2958 
2959 	return len;
2960 }
2961 
2962 /*
2963  * The close routine. Since this is client initiated, we do nothing
2964  */
2965 
2966 static void bc_close(struct rpc_xprt *xprt)
2967 {
2968 	xprt_disconnect_done(xprt);
2969 }
2970 
2971 /*
2972  * The xprt destroy routine. Again, because this connection is client
2973  * initiated, we do nothing
2974  */
2975 
2976 static void bc_destroy(struct rpc_xprt *xprt)
2977 {
2978 	dprintk("RPC:       bc_destroy xprt %p\n", xprt);
2979 
2980 	xs_xprt_free(xprt);
2981 	module_put(THIS_MODULE);
2982 }
2983 
2984 static const struct rpc_xprt_ops xs_local_ops = {
2985 	.reserve_xprt		= xprt_reserve_xprt,
2986 	.release_xprt		= xprt_release_xprt,
2987 	.alloc_slot		= xprt_alloc_slot,
2988 	.free_slot		= xprt_free_slot,
2989 	.rpcbind		= xs_local_rpcbind,
2990 	.set_port		= xs_local_set_port,
2991 	.connect		= xs_local_connect,
2992 	.buf_alloc		= rpc_malloc,
2993 	.buf_free		= rpc_free,
2994 	.prepare_request	= xs_stream_prepare_request,
2995 	.send_request		= xs_local_send_request,
2996 	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
2997 	.close			= xs_close,
2998 	.destroy		= xs_destroy,
2999 	.print_stats		= xs_local_print_stats,
3000 	.enable_swap		= xs_enable_swap,
3001 	.disable_swap		= xs_disable_swap,
3002 };
3003 
3004 static const struct rpc_xprt_ops xs_udp_ops = {
3005 	.set_buffer_size	= xs_udp_set_buffer_size,
3006 	.reserve_xprt		= xprt_reserve_xprt_cong,
3007 	.release_xprt		= xprt_release_xprt_cong,
3008 	.alloc_slot		= xprt_alloc_slot,
3009 	.free_slot		= xprt_free_slot,
3010 	.rpcbind		= rpcb_getport_async,
3011 	.set_port		= xs_set_port,
3012 	.connect		= xs_connect,
3013 	.get_srcaddr		= xs_sock_srcaddr,
3014 	.get_srcport		= xs_sock_srcport,
3015 	.buf_alloc		= rpc_malloc,
3016 	.buf_free		= rpc_free,
3017 	.send_request		= xs_udp_send_request,
3018 	.wait_for_reply_request	= xprt_wait_for_reply_request_rtt,
3019 	.timer			= xs_udp_timer,
3020 	.release_request	= xprt_release_rqst_cong,
3021 	.close			= xs_close,
3022 	.destroy		= xs_destroy,
3023 	.print_stats		= xs_udp_print_stats,
3024 	.enable_swap		= xs_enable_swap,
3025 	.disable_swap		= xs_disable_swap,
3026 	.inject_disconnect	= xs_inject_disconnect,
3027 };
3028 
3029 static const struct rpc_xprt_ops xs_tcp_ops = {
3030 	.reserve_xprt		= xprt_reserve_xprt,
3031 	.release_xprt		= xprt_release_xprt,
3032 	.alloc_slot		= xprt_alloc_slot,
3033 	.free_slot		= xprt_free_slot,
3034 	.rpcbind		= rpcb_getport_async,
3035 	.set_port		= xs_set_port,
3036 	.connect		= xs_connect,
3037 	.get_srcaddr		= xs_sock_srcaddr,
3038 	.get_srcport		= xs_sock_srcport,
3039 	.buf_alloc		= rpc_malloc,
3040 	.buf_free		= rpc_free,
3041 	.prepare_request	= xs_stream_prepare_request,
3042 	.send_request		= xs_tcp_send_request,
3043 	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
3044 	.close			= xs_tcp_shutdown,
3045 	.destroy		= xs_destroy,
3046 	.set_connect_timeout	= xs_tcp_set_connect_timeout,
3047 	.print_stats		= xs_tcp_print_stats,
3048 	.enable_swap		= xs_enable_swap,
3049 	.disable_swap		= xs_disable_swap,
3050 	.inject_disconnect	= xs_inject_disconnect,
3051 #ifdef CONFIG_SUNRPC_BACKCHANNEL
3052 	.bc_setup		= xprt_setup_bc,
3053 	.bc_maxpayload		= xs_tcp_bc_maxpayload,
3054 	.bc_num_slots		= xprt_bc_max_slots,
3055 	.bc_free_rqst		= xprt_free_bc_rqst,
3056 	.bc_destroy		= xprt_destroy_bc,
3057 #endif
3058 };
3059 
3060 /*
3061  * The rpc_xprt_ops for the server backchannel
3062  */
3063 
3064 static const struct rpc_xprt_ops bc_tcp_ops = {
3065 	.reserve_xprt		= xprt_reserve_xprt,
3066 	.release_xprt		= xprt_release_xprt,
3067 	.alloc_slot		= xprt_alloc_slot,
3068 	.free_slot		= xprt_free_slot,
3069 	.buf_alloc		= bc_malloc,
3070 	.buf_free		= bc_free,
3071 	.send_request		= bc_send_request,
3072 	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
3073 	.close			= bc_close,
3074 	.destroy		= bc_destroy,
3075 	.print_stats		= xs_tcp_print_stats,
3076 	.enable_swap		= xs_enable_swap,
3077 	.disable_swap		= xs_disable_swap,
3078 	.inject_disconnect	= xs_inject_disconnect,
3079 };
3080 
3081 static int xs_init_anyaddr(const int family, struct sockaddr *sap)
3082 {
3083 	static const struct sockaddr_in sin = {
3084 		.sin_family		= AF_INET,
3085 		.sin_addr.s_addr	= htonl(INADDR_ANY),
3086 	};
3087 	static const struct sockaddr_in6 sin6 = {
3088 		.sin6_family		= AF_INET6,
3089 		.sin6_addr		= IN6ADDR_ANY_INIT,
3090 	};
3091 
3092 	switch (family) {
3093 	case AF_LOCAL:
3094 		break;
3095 	case AF_INET:
3096 		memcpy(sap, &sin, sizeof(sin));
3097 		break;
3098 	case AF_INET6:
3099 		memcpy(sap, &sin6, sizeof(sin6));
3100 		break;
3101 	default:
3102 		dprintk("RPC:       %s: Bad address family\n", __func__);
3103 		return -EAFNOSUPPORT;
3104 	}
3105 	return 0;
3106 }
3107 
3108 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
3109 				      unsigned int slot_table_size,
3110 				      unsigned int max_slot_table_size)
3111 {
3112 	struct rpc_xprt *xprt;
3113 	struct sock_xprt *new;
3114 
3115 	if (args->addrlen > sizeof(xprt->addr)) {
3116 		dprintk("RPC:       xs_setup_xprt: address too large\n");
3117 		return ERR_PTR(-EBADF);
3118 	}
3119 
3120 	xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
3121 			max_slot_table_size);
3122 	if (xprt == NULL) {
3123 		dprintk("RPC:       xs_setup_xprt: couldn't allocate "
3124 				"rpc_xprt\n");
3125 		return ERR_PTR(-ENOMEM);
3126 	}
3127 
3128 	new = container_of(xprt, struct sock_xprt, xprt);
3129 	mutex_init(&new->recv_mutex);
3130 	memcpy(&xprt->addr, args->dstaddr, args->addrlen);
3131 	xprt->addrlen = args->addrlen;
3132 	if (args->srcaddr)
3133 		memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
3134 	else {
3135 		int err;
3136 		err = xs_init_anyaddr(args->dstaddr->sa_family,
3137 					(struct sockaddr *)&new->srcaddr);
3138 		if (err != 0) {
3139 			xprt_free(xprt);
3140 			return ERR_PTR(err);
3141 		}
3142 	}
3143 
3144 	return xprt;
3145 }
3146 
3147 static const struct rpc_timeout xs_local_default_timeout = {
3148 	.to_initval = 10 * HZ,
3149 	.to_maxval = 10 * HZ,
3150 	.to_retries = 2,
3151 };
3152 
3153 /**
3154  * xs_setup_local - Set up transport to use an AF_LOCAL socket
3155  * @args: rpc transport creation arguments
3156  *
3157  * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
3158  */
3159 static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
3160 {
3161 	struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
3162 	struct sock_xprt *transport;
3163 	struct rpc_xprt *xprt;
3164 	struct rpc_xprt *ret;
3165 
3166 	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3167 			xprt_max_tcp_slot_table_entries);
3168 	if (IS_ERR(xprt))
3169 		return xprt;
3170 	transport = container_of(xprt, struct sock_xprt, xprt);
3171 
3172 	xprt->prot = 0;
3173 	xprt->xprt_class = &xs_local_transport;
3174 	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3175 
3176 	xprt->bind_timeout = XS_BIND_TO;
3177 	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
3178 	xprt->idle_timeout = XS_IDLE_DISC_TO;
3179 
3180 	xprt->ops = &xs_local_ops;
3181 	xprt->timeout = &xs_local_default_timeout;
3182 
3183 	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
3184 	INIT_WORK(&transport->error_worker, xs_error_handle);
3185 	INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket);
3186 
3187 	switch (sun->sun_family) {
3188 	case AF_LOCAL:
3189 		if (sun->sun_path[0] != '/' && sun->sun_path[0] != '\0') {
3190 			dprintk("RPC:       bad AF_LOCAL address: %s\n",
3191 					sun->sun_path);
3192 			ret = ERR_PTR(-EINVAL);
3193 			goto out_err;
3194 		}
3195 		xprt_set_bound(xprt);
3196 		xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
3197 		break;
3198 	default:
3199 		ret = ERR_PTR(-EAFNOSUPPORT);
3200 		goto out_err;
3201 	}
3202 
3203 	dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
3204 			xprt->address_strings[RPC_DISPLAY_ADDR]);
3205 
3206 	if (try_module_get(THIS_MODULE))
3207 		return xprt;
3208 	ret = ERR_PTR(-EINVAL);
3209 out_err:
3210 	xs_xprt_free(xprt);
3211 	return ret;
3212 }
3213 
3214 static const struct rpc_timeout xs_udp_default_timeout = {
3215 	.to_initval = 5 * HZ,
3216 	.to_maxval = 30 * HZ,
3217 	.to_increment = 5 * HZ,
3218 	.to_retries = 5,
3219 };
3220 
3221 /**
3222  * xs_setup_udp - Set up transport to use a UDP socket
3223  * @args: rpc transport creation arguments
3224  *
3225  */
3226 static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
3227 {
3228 	struct sockaddr *addr = args->dstaddr;
3229 	struct rpc_xprt *xprt;
3230 	struct sock_xprt *transport;
3231 	struct rpc_xprt *ret;
3232 
3233 	xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
3234 			xprt_udp_slot_table_entries);
3235 	if (IS_ERR(xprt))
3236 		return xprt;
3237 	transport = container_of(xprt, struct sock_xprt, xprt);
3238 
3239 	xprt->prot = IPPROTO_UDP;
3240 	xprt->xprt_class = &xs_udp_transport;
3241 	/* XXX: header size can vary due to auth type, IPv6, etc. */
3242 	xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
3243 
3244 	xprt->bind_timeout = XS_BIND_TO;
3245 	xprt->reestablish_timeout = XS_UDP_REEST_TO;
3246 	xprt->idle_timeout = XS_IDLE_DISC_TO;
3247 
3248 	xprt->ops = &xs_udp_ops;
3249 
3250 	xprt->timeout = &xs_udp_default_timeout;
3251 
3252 	INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
3253 	INIT_WORK(&transport->error_worker, xs_error_handle);
3254 	INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
3255 
3256 	switch (addr->sa_family) {
3257 	case AF_INET:
3258 		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3259 			xprt_set_bound(xprt);
3260 
3261 		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
3262 		break;
3263 	case AF_INET6:
3264 		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3265 			xprt_set_bound(xprt);
3266 
3267 		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
3268 		break;
3269 	default:
3270 		ret = ERR_PTR(-EAFNOSUPPORT);
3271 		goto out_err;
3272 	}
3273 
3274 	if (xprt_bound(xprt))
3275 		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3276 				xprt->address_strings[RPC_DISPLAY_ADDR],
3277 				xprt->address_strings[RPC_DISPLAY_PORT],
3278 				xprt->address_strings[RPC_DISPLAY_PROTO]);
3279 	else
3280 		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3281 				xprt->address_strings[RPC_DISPLAY_ADDR],
3282 				xprt->address_strings[RPC_DISPLAY_PROTO]);
3283 
3284 	if (try_module_get(THIS_MODULE))
3285 		return xprt;
3286 	ret = ERR_PTR(-EINVAL);
3287 out_err:
3288 	xs_xprt_free(xprt);
3289 	return ret;
3290 }
3291 
3292 static const struct rpc_timeout xs_tcp_default_timeout = {
3293 	.to_initval = 60 * HZ,
3294 	.to_maxval = 60 * HZ,
3295 	.to_retries = 2,
3296 };
3297 
3298 /**
3299  * xs_setup_tcp - Set up transport to use a TCP socket
3300  * @args: rpc transport creation arguments
3301  *
3302  */
3303 static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
3304 {
3305 	struct sockaddr *addr = args->dstaddr;
3306 	struct rpc_xprt *xprt;
3307 	struct sock_xprt *transport;
3308 	struct rpc_xprt *ret;
3309 	unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
3310 
3311 	if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
3312 		max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
3313 
3314 	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3315 			max_slot_table_size);
3316 	if (IS_ERR(xprt))
3317 		return xprt;
3318 	transport = container_of(xprt, struct sock_xprt, xprt);
3319 
3320 	xprt->prot = IPPROTO_TCP;
3321 	xprt->xprt_class = &xs_tcp_transport;
3322 	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3323 
3324 	xprt->bind_timeout = XS_BIND_TO;
3325 	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
3326 	xprt->idle_timeout = XS_IDLE_DISC_TO;
3327 
3328 	xprt->ops = &xs_tcp_ops;
3329 	xprt->timeout = &xs_tcp_default_timeout;
3330 
3331 	xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
3332 	xprt->connect_timeout = xprt->timeout->to_initval *
3333 		(xprt->timeout->to_retries + 1);
3334 
3335 	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
3336 	INIT_WORK(&transport->error_worker, xs_error_handle);
3337 	INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
3338 
3339 	switch (addr->sa_family) {
3340 	case AF_INET:
3341 		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3342 			xprt_set_bound(xprt);
3343 
3344 		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
3345 		break;
3346 	case AF_INET6:
3347 		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3348 			xprt_set_bound(xprt);
3349 
3350 		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
3351 		break;
3352 	default:
3353 		ret = ERR_PTR(-EAFNOSUPPORT);
3354 		goto out_err;
3355 	}
3356 
3357 	if (xprt_bound(xprt))
3358 		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3359 				xprt->address_strings[RPC_DISPLAY_ADDR],
3360 				xprt->address_strings[RPC_DISPLAY_PORT],
3361 				xprt->address_strings[RPC_DISPLAY_PROTO]);
3362 	else
3363 		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3364 				xprt->address_strings[RPC_DISPLAY_ADDR],
3365 				xprt->address_strings[RPC_DISPLAY_PROTO]);
3366 
3367 	if (try_module_get(THIS_MODULE))
3368 		return xprt;
3369 	ret = ERR_PTR(-EINVAL);
3370 out_err:
3371 	xs_xprt_free(xprt);
3372 	return ret;
3373 }
3374 
3375 /**
3376  * xs_setup_tcp_tls - Set up transport to use a TCP with TLS
3377  * @args: rpc transport creation arguments
3378  *
3379  */
3380 static struct rpc_xprt *xs_setup_tcp_tls(struct xprt_create *args)
3381 {
3382 	struct sockaddr *addr = args->dstaddr;
3383 	struct rpc_xprt *xprt;
3384 	struct sock_xprt *transport;
3385 	struct rpc_xprt *ret;
3386 	unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
3387 
3388 	if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
3389 		max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
3390 
3391 	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3392 			     max_slot_table_size);
3393 	if (IS_ERR(xprt))
3394 		return xprt;
3395 	transport = container_of(xprt, struct sock_xprt, xprt);
3396 
3397 	xprt->prot = IPPROTO_TCP;
3398 	xprt->xprt_class = &xs_tcp_transport;
3399 	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3400 
3401 	xprt->bind_timeout = XS_BIND_TO;
3402 	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
3403 	xprt->idle_timeout = XS_IDLE_DISC_TO;
3404 
3405 	xprt->ops = &xs_tcp_ops;
3406 	xprt->timeout = &xs_tcp_default_timeout;
3407 
3408 	xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
3409 	xprt->connect_timeout = xprt->timeout->to_initval *
3410 		(xprt->timeout->to_retries + 1);
3411 
3412 	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
3413 	INIT_WORK(&transport->error_worker, xs_error_handle);
3414 
3415 	switch (args->xprtsec.policy) {
3416 	case RPC_XPRTSEC_TLS_ANON:
3417 	case RPC_XPRTSEC_TLS_X509:
3418 		xprt->xprtsec = args->xprtsec;
3419 		INIT_DELAYED_WORK(&transport->connect_worker,
3420 				  xs_tcp_tls_setup_socket);
3421 		break;
3422 	default:
3423 		ret = ERR_PTR(-EACCES);
3424 		goto out_err;
3425 	}
3426 
3427 	switch (addr->sa_family) {
3428 	case AF_INET:
3429 		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3430 			xprt_set_bound(xprt);
3431 
3432 		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
3433 		break;
3434 	case AF_INET6:
3435 		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3436 			xprt_set_bound(xprt);
3437 
3438 		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
3439 		break;
3440 	default:
3441 		ret = ERR_PTR(-EAFNOSUPPORT);
3442 		goto out_err;
3443 	}
3444 
3445 	if (xprt_bound(xprt))
3446 		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3447 			xprt->address_strings[RPC_DISPLAY_ADDR],
3448 			xprt->address_strings[RPC_DISPLAY_PORT],
3449 			xprt->address_strings[RPC_DISPLAY_PROTO]);
3450 	else
3451 		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3452 			xprt->address_strings[RPC_DISPLAY_ADDR],
3453 			xprt->address_strings[RPC_DISPLAY_PROTO]);
3454 
3455 	if (try_module_get(THIS_MODULE))
3456 		return xprt;
3457 	ret = ERR_PTR(-EINVAL);
3458 out_err:
3459 	xs_xprt_free(xprt);
3460 	return ret;
3461 }
3462 
3463 /**
3464  * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
3465  * @args: rpc transport creation arguments
3466  *
3467  */
3468 static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
3469 {
3470 	struct sockaddr *addr = args->dstaddr;
3471 	struct rpc_xprt *xprt;
3472 	struct sock_xprt *transport;
3473 	struct svc_sock *bc_sock;
3474 	struct rpc_xprt *ret;
3475 
3476 	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3477 			xprt_tcp_slot_table_entries);
3478 	if (IS_ERR(xprt))
3479 		return xprt;
3480 	transport = container_of(xprt, struct sock_xprt, xprt);
3481 
3482 	xprt->prot = IPPROTO_TCP;
3483 	xprt->xprt_class = &xs_bc_tcp_transport;
3484 	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3485 	xprt->timeout = &xs_tcp_default_timeout;
3486 
3487 	/* backchannel */
3488 	xprt_set_bound(xprt);
3489 	xprt->bind_timeout = 0;
3490 	xprt->reestablish_timeout = 0;
3491 	xprt->idle_timeout = 0;
3492 
3493 	xprt->ops = &bc_tcp_ops;
3494 
3495 	switch (addr->sa_family) {
3496 	case AF_INET:
3497 		xs_format_peer_addresses(xprt, "tcp",
3498 					 RPCBIND_NETID_TCP);
3499 		break;
3500 	case AF_INET6:
3501 		xs_format_peer_addresses(xprt, "tcp",
3502 				   RPCBIND_NETID_TCP6);
3503 		break;
3504 	default:
3505 		ret = ERR_PTR(-EAFNOSUPPORT);
3506 		goto out_err;
3507 	}
3508 
3509 	dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3510 			xprt->address_strings[RPC_DISPLAY_ADDR],
3511 			xprt->address_strings[RPC_DISPLAY_PORT],
3512 			xprt->address_strings[RPC_DISPLAY_PROTO]);
3513 
3514 	/*
3515 	 * Once we've associated a backchannel xprt with a connection,
3516 	 * we want to keep it around as long as the connection lasts,
3517 	 * in case we need to start using it for a backchannel again;
3518 	 * this reference won't be dropped until bc_xprt is destroyed.
3519 	 */
3520 	xprt_get(xprt);
3521 	args->bc_xprt->xpt_bc_xprt = xprt;
3522 	xprt->bc_xprt = args->bc_xprt;
3523 	bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3524 	transport->sock = bc_sock->sk_sock;
3525 	transport->inet = bc_sock->sk_sk;
3526 
3527 	/*
3528 	 * Since we don't want connections for the backchannel, we set
3529 	 * the xprt status to connected
3530 	 */
3531 	xprt_set_connected(xprt);
3532 
3533 	if (try_module_get(THIS_MODULE))
3534 		return xprt;
3535 
3536 	args->bc_xprt->xpt_bc_xprt = NULL;
3537 	args->bc_xprt->xpt_bc_xps = NULL;
3538 	xprt_put(xprt);
3539 	ret = ERR_PTR(-EINVAL);
3540 out_err:
3541 	xs_xprt_free(xprt);
3542 	return ret;
3543 }
3544 
3545 static struct xprt_class	xs_local_transport = {
3546 	.list		= LIST_HEAD_INIT(xs_local_transport.list),
3547 	.name		= "named UNIX socket",
3548 	.owner		= THIS_MODULE,
3549 	.ident		= XPRT_TRANSPORT_LOCAL,
3550 	.setup		= xs_setup_local,
3551 	.netid		= { "" },
3552 };
3553 
3554 static struct xprt_class	xs_udp_transport = {
3555 	.list		= LIST_HEAD_INIT(xs_udp_transport.list),
3556 	.name		= "udp",
3557 	.owner		= THIS_MODULE,
3558 	.ident		= XPRT_TRANSPORT_UDP,
3559 	.setup		= xs_setup_udp,
3560 	.netid		= { "udp", "udp6", "" },
3561 };
3562 
3563 static struct xprt_class	xs_tcp_transport = {
3564 	.list		= LIST_HEAD_INIT(xs_tcp_transport.list),
3565 	.name		= "tcp",
3566 	.owner		= THIS_MODULE,
3567 	.ident		= XPRT_TRANSPORT_TCP,
3568 	.setup		= xs_setup_tcp,
3569 	.netid		= { "tcp", "tcp6", "" },
3570 };
3571 
3572 static struct xprt_class	xs_tcp_tls_transport = {
3573 	.list		= LIST_HEAD_INIT(xs_tcp_tls_transport.list),
3574 	.name		= "tcp-with-tls",
3575 	.owner		= THIS_MODULE,
3576 	.ident		= XPRT_TRANSPORT_TCP_TLS,
3577 	.setup		= xs_setup_tcp_tls,
3578 	.netid		= { "tcp", "tcp6", "" },
3579 };
3580 
3581 static struct xprt_class	xs_bc_tcp_transport = {
3582 	.list		= LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3583 	.name		= "tcp NFSv4.1 backchannel",
3584 	.owner		= THIS_MODULE,
3585 	.ident		= XPRT_TRANSPORT_BC_TCP,
3586 	.setup		= xs_setup_bc_tcp,
3587 	.netid		= { "" },
3588 };
3589 
3590 /**
3591  * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3592  *
3593  */
3594 int init_socket_xprt(void)
3595 {
3596 	if (!sunrpc_table_header)
3597 		sunrpc_table_header = register_sysctl("sunrpc", xs_tunables_table);
3598 
3599 	xprt_register_transport(&xs_local_transport);
3600 	xprt_register_transport(&xs_udp_transport);
3601 	xprt_register_transport(&xs_tcp_transport);
3602 	xprt_register_transport(&xs_tcp_tls_transport);
3603 	xprt_register_transport(&xs_bc_tcp_transport);
3604 
3605 	return 0;
3606 }
3607 
3608 /**
3609  * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3610  *
3611  */
3612 void cleanup_socket_xprt(void)
3613 {
3614 	if (sunrpc_table_header) {
3615 		unregister_sysctl_table(sunrpc_table_header);
3616 		sunrpc_table_header = NULL;
3617 	}
3618 
3619 	xprt_unregister_transport(&xs_local_transport);
3620 	xprt_unregister_transport(&xs_udp_transport);
3621 	xprt_unregister_transport(&xs_tcp_transport);
3622 	xprt_unregister_transport(&xs_tcp_tls_transport);
3623 	xprt_unregister_transport(&xs_bc_tcp_transport);
3624 }
3625 
3626 static int param_set_portnr(const char *val, const struct kernel_param *kp)
3627 {
3628 	return param_set_uint_minmax(val, kp,
3629 			RPC_MIN_RESVPORT,
3630 			RPC_MAX_RESVPORT);
3631 }
3632 
3633 static const struct kernel_param_ops param_ops_portnr = {
3634 	.set = param_set_portnr,
3635 	.get = param_get_uint,
3636 };
3637 
3638 #define param_check_portnr(name, p) \
3639 	__param_check(name, p, unsigned int);
3640 
3641 module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3642 module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3643 
3644 static int param_set_slot_table_size(const char *val,
3645 				     const struct kernel_param *kp)
3646 {
3647 	return param_set_uint_minmax(val, kp,
3648 			RPC_MIN_SLOT_TABLE,
3649 			RPC_MAX_SLOT_TABLE);
3650 }
3651 
3652 static const struct kernel_param_ops param_ops_slot_table_size = {
3653 	.set = param_set_slot_table_size,
3654 	.get = param_get_uint,
3655 };
3656 
3657 #define param_check_slot_table_size(name, p) \
3658 	__param_check(name, p, unsigned int);
3659 
3660 static int param_set_max_slot_table_size(const char *val,
3661 				     const struct kernel_param *kp)
3662 {
3663 	return param_set_uint_minmax(val, kp,
3664 			RPC_MIN_SLOT_TABLE,
3665 			RPC_MAX_SLOT_TABLE_LIMIT);
3666 }
3667 
3668 static const struct kernel_param_ops param_ops_max_slot_table_size = {
3669 	.set = param_set_max_slot_table_size,
3670 	.get = param_get_uint,
3671 };
3672 
3673 #define param_check_max_slot_table_size(name, p) \
3674 	__param_check(name, p, unsigned int);
3675 
3676 module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3677 		   slot_table_size, 0644);
3678 module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3679 		   max_slot_table_size, 0644);
3680 module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3681 		   slot_table_size, 0644);
3682