xref: /linux/net/sunrpc/xprtsock.c (revision bf5802238dc181b1f7375d358af1d01cd72d1c11)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * linux/net/sunrpc/xprtsock.c
4  *
5  * Client-side transport implementation for sockets.
6  *
7  * TCP callback races fixes (C) 1998 Red Hat
8  * TCP send fixes (C) 1998 Red Hat
9  * TCP NFS related read + write fixes
10  *  (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
11  *
12  * Rewrite of larges part of the code in order to stabilize TCP stuff.
13  * Fix behaviour when socket buffer is full.
14  *  (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no>
15  *
16  * IP socket transport implementation, (C) 2005 Chuck Lever <cel@netapp.com>
17  *
18  * IPv6 support contributed by Gilles Quillard, Bull Open Source, 2005.
19  *   <gilles.quillard@bull.net>
20  */
21 
22 #include <linux/types.h>
23 #include <linux/string.h>
24 #include <linux/slab.h>
25 #include <linux/module.h>
26 #include <linux/capability.h>
27 #include <linux/pagemap.h>
28 #include <linux/errno.h>
29 #include <linux/socket.h>
30 #include <linux/in.h>
31 #include <linux/net.h>
32 #include <linux/mm.h>
33 #include <linux/un.h>
34 #include <linux/udp.h>
35 #include <linux/tcp.h>
36 #include <linux/sunrpc/clnt.h>
37 #include <linux/sunrpc/addr.h>
38 #include <linux/sunrpc/sched.h>
39 #include <linux/sunrpc/svcsock.h>
40 #include <linux/sunrpc/xprtsock.h>
41 #include <linux/file.h>
42 #ifdef CONFIG_SUNRPC_BACKCHANNEL
43 #include <linux/sunrpc/bc_xprt.h>
44 #endif
45 
46 #include <net/sock.h>
47 #include <net/checksum.h>
48 #include <net/udp.h>
49 #include <net/tcp.h>
50 #include <net/tls_prot.h>
51 #include <net/handshake.h>
52 
53 #include <linux/bvec.h>
54 #include <linux/highmem.h>
55 #include <linux/uio.h>
56 #include <linux/sched/mm.h>
57 
58 #include <trace/events/sock.h>
59 #include <trace/events/sunrpc.h>
60 
61 #include "socklib.h"
62 #include "sunrpc.h"
63 
64 static void xs_close(struct rpc_xprt *xprt);
65 static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock);
66 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
67 		struct socket *sock);
68 
69 /*
70  * xprtsock tunables
71  */
72 static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
73 static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
74 static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
75 
76 static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
77 static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
78 
79 #define XS_TCP_LINGER_TO	(15U * HZ)
80 static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
81 
82 /*
83  * We can register our own files under /proc/sys/sunrpc by
84  * calling register_sysctl() again.  The files in that
85  * directory become the union of all files registered there.
86  *
87  * We simply need to make sure that we don't collide with
88  * someone else's file names!
89  */
90 
91 static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
92 static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
93 static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
94 static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
95 static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
96 
97 static struct ctl_table_header *sunrpc_table_header;
98 
99 static struct xprt_class xs_local_transport;
100 static struct xprt_class xs_udp_transport;
101 static struct xprt_class xs_tcp_transport;
102 static struct xprt_class xs_tcp_tls_transport;
103 static struct xprt_class xs_bc_tcp_transport;
104 
105 /*
106  * FIXME: changing the UDP slot table size should also resize the UDP
107  *        socket buffers for existing UDP transports
108  */
109 static struct ctl_table xs_tunables_table[] = {
110 	{
111 		.procname	= "udp_slot_table_entries",
112 		.data		= &xprt_udp_slot_table_entries,
113 		.maxlen		= sizeof(unsigned int),
114 		.mode		= 0644,
115 		.proc_handler	= proc_dointvec_minmax,
116 		.extra1		= &min_slot_table_size,
117 		.extra2		= &max_slot_table_size
118 	},
119 	{
120 		.procname	= "tcp_slot_table_entries",
121 		.data		= &xprt_tcp_slot_table_entries,
122 		.maxlen		= sizeof(unsigned int),
123 		.mode		= 0644,
124 		.proc_handler	= proc_dointvec_minmax,
125 		.extra1		= &min_slot_table_size,
126 		.extra2		= &max_slot_table_size
127 	},
128 	{
129 		.procname	= "tcp_max_slot_table_entries",
130 		.data		= &xprt_max_tcp_slot_table_entries,
131 		.maxlen		= sizeof(unsigned int),
132 		.mode		= 0644,
133 		.proc_handler	= proc_dointvec_minmax,
134 		.extra1		= &min_slot_table_size,
135 		.extra2		= &max_tcp_slot_table_limit
136 	},
137 	{
138 		.procname	= "min_resvport",
139 		.data		= &xprt_min_resvport,
140 		.maxlen		= sizeof(unsigned int),
141 		.mode		= 0644,
142 		.proc_handler	= proc_dointvec_minmax,
143 		.extra1		= &xprt_min_resvport_limit,
144 		.extra2		= &xprt_max_resvport_limit
145 	},
146 	{
147 		.procname	= "max_resvport",
148 		.data		= &xprt_max_resvport,
149 		.maxlen		= sizeof(unsigned int),
150 		.mode		= 0644,
151 		.proc_handler	= proc_dointvec_minmax,
152 		.extra1		= &xprt_min_resvport_limit,
153 		.extra2		= &xprt_max_resvport_limit
154 	},
155 	{
156 		.procname	= "tcp_fin_timeout",
157 		.data		= &xs_tcp_fin_timeout,
158 		.maxlen		= sizeof(xs_tcp_fin_timeout),
159 		.mode		= 0644,
160 		.proc_handler	= proc_dointvec_jiffies,
161 	},
162 	{ },
163 };
164 
165 /*
166  * Wait duration for a reply from the RPC portmapper.
167  */
168 #define XS_BIND_TO		(60U * HZ)
169 
170 /*
171  * Delay if a UDP socket connect error occurs.  This is most likely some
172  * kind of resource problem on the local host.
173  */
174 #define XS_UDP_REEST_TO		(2U * HZ)
175 
176 /*
177  * The reestablish timeout allows clients to delay for a bit before attempting
178  * to reconnect to a server that just dropped our connection.
179  *
180  * We implement an exponential backoff when trying to reestablish a TCP
181  * transport connection with the server.  Some servers like to drop a TCP
182  * connection when they are overworked, so we start with a short timeout and
183  * increase over time if the server is down or not responding.
184  */
185 #define XS_TCP_INIT_REEST_TO	(3U * HZ)
186 
187 /*
188  * TCP idle timeout; client drops the transport socket if it is idle
189  * for this long.  Note that we also timeout UDP sockets to prevent
190  * holding port numbers when there is no RPC traffic.
191  */
192 #define XS_IDLE_DISC_TO		(5U * 60 * HZ)
193 
194 /*
195  * TLS handshake timeout.
196  */
197 #define XS_TLS_HANDSHAKE_TO	(10U * HZ)
198 
199 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
200 # undef  RPC_DEBUG_DATA
201 # define RPCDBG_FACILITY	RPCDBG_TRANS
202 #endif
203 
204 #ifdef RPC_DEBUG_DATA
205 static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
206 {
207 	u8 *buf = (u8 *) packet;
208 	int j;
209 
210 	dprintk("RPC:       %s\n", msg);
211 	for (j = 0; j < count && j < 128; j += 4) {
212 		if (!(j & 31)) {
213 			if (j)
214 				dprintk("\n");
215 			dprintk("0x%04x ", j);
216 		}
217 		dprintk("%02x%02x%02x%02x ",
218 			buf[j], buf[j+1], buf[j+2], buf[j+3]);
219 	}
220 	dprintk("\n");
221 }
222 #else
223 static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
224 {
225 	/* NOP */
226 }
227 #endif
228 
229 static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
230 {
231 	return (struct rpc_xprt *) sk->sk_user_data;
232 }
233 
234 static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
235 {
236 	return (struct sockaddr *) &xprt->addr;
237 }
238 
239 static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
240 {
241 	return (struct sockaddr_un *) &xprt->addr;
242 }
243 
244 static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
245 {
246 	return (struct sockaddr_in *) &xprt->addr;
247 }
248 
249 static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
250 {
251 	return (struct sockaddr_in6 *) &xprt->addr;
252 }
253 
254 static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
255 {
256 	struct sockaddr *sap = xs_addr(xprt);
257 	struct sockaddr_in6 *sin6;
258 	struct sockaddr_in *sin;
259 	struct sockaddr_un *sun;
260 	char buf[128];
261 
262 	switch (sap->sa_family) {
263 	case AF_LOCAL:
264 		sun = xs_addr_un(xprt);
265 		if (sun->sun_path[0]) {
266 			strscpy(buf, sun->sun_path, sizeof(buf));
267 		} else {
268 			buf[0] = '@';
269 			strscpy(buf+1, sun->sun_path+1, sizeof(buf)-1);
270 		}
271 		xprt->address_strings[RPC_DISPLAY_ADDR] =
272 						kstrdup(buf, GFP_KERNEL);
273 		break;
274 	case AF_INET:
275 		(void)rpc_ntop(sap, buf, sizeof(buf));
276 		xprt->address_strings[RPC_DISPLAY_ADDR] =
277 						kstrdup(buf, GFP_KERNEL);
278 		sin = xs_addr_in(xprt);
279 		snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
280 		break;
281 	case AF_INET6:
282 		(void)rpc_ntop(sap, buf, sizeof(buf));
283 		xprt->address_strings[RPC_DISPLAY_ADDR] =
284 						kstrdup(buf, GFP_KERNEL);
285 		sin6 = xs_addr_in6(xprt);
286 		snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
287 		break;
288 	default:
289 		BUG();
290 	}
291 
292 	xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
293 }
294 
295 static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
296 {
297 	struct sockaddr *sap = xs_addr(xprt);
298 	char buf[128];
299 
300 	snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
301 	xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
302 
303 	snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
304 	xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
305 }
306 
307 static void xs_format_peer_addresses(struct rpc_xprt *xprt,
308 				     const char *protocol,
309 				     const char *netid)
310 {
311 	xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
312 	xprt->address_strings[RPC_DISPLAY_NETID] = netid;
313 	xs_format_common_peer_addresses(xprt);
314 	xs_format_common_peer_ports(xprt);
315 }
316 
317 static void xs_update_peer_port(struct rpc_xprt *xprt)
318 {
319 	kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
320 	kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
321 
322 	xs_format_common_peer_ports(xprt);
323 }
324 
325 static void xs_free_peer_addresses(struct rpc_xprt *xprt)
326 {
327 	unsigned int i;
328 
329 	for (i = 0; i < RPC_DISPLAY_MAX; i++)
330 		switch (i) {
331 		case RPC_DISPLAY_PROTO:
332 		case RPC_DISPLAY_NETID:
333 			continue;
334 		default:
335 			kfree(xprt->address_strings[i]);
336 		}
337 }
338 
339 static size_t
340 xs_alloc_sparse_pages(struct xdr_buf *buf, size_t want, gfp_t gfp)
341 {
342 	size_t i,n;
343 
344 	if (!want || !(buf->flags & XDRBUF_SPARSE_PAGES))
345 		return want;
346 	n = (buf->page_base + want + PAGE_SIZE - 1) >> PAGE_SHIFT;
347 	for (i = 0; i < n; i++) {
348 		if (buf->pages[i])
349 			continue;
350 		buf->bvec[i].bv_page = buf->pages[i] = alloc_page(gfp);
351 		if (!buf->pages[i]) {
352 			i *= PAGE_SIZE;
353 			return i > buf->page_base ? i - buf->page_base : 0;
354 		}
355 	}
356 	return want;
357 }
358 
359 static int
360 xs_sock_process_cmsg(struct socket *sock, struct msghdr *msg,
361 		     struct cmsghdr *cmsg, int ret)
362 {
363 	u8 content_type = tls_get_record_type(sock->sk, cmsg);
364 	u8 level, description;
365 
366 	switch (content_type) {
367 	case 0:
368 		break;
369 	case TLS_RECORD_TYPE_DATA:
370 		/* TLS sets EOR at the end of each application data
371 		 * record, even though there might be more frames
372 		 * waiting to be decrypted.
373 		 */
374 		msg->msg_flags &= ~MSG_EOR;
375 		break;
376 	case TLS_RECORD_TYPE_ALERT:
377 		tls_alert_recv(sock->sk, msg, &level, &description);
378 		ret = (level == TLS_ALERT_LEVEL_FATAL) ?
379 			-EACCES : -EAGAIN;
380 		break;
381 	default:
382 		/* discard this record type */
383 		ret = -EAGAIN;
384 	}
385 	return ret;
386 }
387 
388 static int
389 xs_sock_recv_cmsg(struct socket *sock, struct msghdr *msg, int flags)
390 {
391 	union {
392 		struct cmsghdr	cmsg;
393 		u8		buf[CMSG_SPACE(sizeof(u8))];
394 	} u;
395 	int ret;
396 
397 	msg->msg_control = &u;
398 	msg->msg_controllen = sizeof(u);
399 	ret = sock_recvmsg(sock, msg, flags);
400 	if (msg->msg_controllen != sizeof(u))
401 		ret = xs_sock_process_cmsg(sock, msg, &u.cmsg, ret);
402 	return ret;
403 }
404 
405 static ssize_t
406 xs_sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags, size_t seek)
407 {
408 	ssize_t ret;
409 	if (seek != 0)
410 		iov_iter_advance(&msg->msg_iter, seek);
411 	ret = xs_sock_recv_cmsg(sock, msg, flags);
412 	return ret > 0 ? ret + seek : ret;
413 }
414 
415 static ssize_t
416 xs_read_kvec(struct socket *sock, struct msghdr *msg, int flags,
417 		struct kvec *kvec, size_t count, size_t seek)
418 {
419 	iov_iter_kvec(&msg->msg_iter, ITER_DEST, kvec, 1, count);
420 	return xs_sock_recvmsg(sock, msg, flags, seek);
421 }
422 
423 static ssize_t
424 xs_read_bvec(struct socket *sock, struct msghdr *msg, int flags,
425 		struct bio_vec *bvec, unsigned long nr, size_t count,
426 		size_t seek)
427 {
428 	iov_iter_bvec(&msg->msg_iter, ITER_DEST, bvec, nr, count);
429 	return xs_sock_recvmsg(sock, msg, flags, seek);
430 }
431 
432 static ssize_t
433 xs_read_discard(struct socket *sock, struct msghdr *msg, int flags,
434 		size_t count)
435 {
436 	iov_iter_discard(&msg->msg_iter, ITER_DEST, count);
437 	return xs_sock_recv_cmsg(sock, msg, flags);
438 }
439 
440 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
441 static void
442 xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
443 {
444 	struct bvec_iter bi = {
445 		.bi_size = count,
446 	};
447 	struct bio_vec bv;
448 
449 	bvec_iter_advance(bvec, &bi, seek & PAGE_MASK);
450 	for_each_bvec(bv, bvec, bi, bi)
451 		flush_dcache_page(bv.bv_page);
452 }
453 #else
454 static inline void
455 xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
456 {
457 }
458 #endif
459 
460 static ssize_t
461 xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags,
462 		struct xdr_buf *buf, size_t count, size_t seek, size_t *read)
463 {
464 	size_t want, seek_init = seek, offset = 0;
465 	ssize_t ret;
466 
467 	want = min_t(size_t, count, buf->head[0].iov_len);
468 	if (seek < want) {
469 		ret = xs_read_kvec(sock, msg, flags, &buf->head[0], want, seek);
470 		if (ret <= 0)
471 			goto sock_err;
472 		offset += ret;
473 		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
474 			goto out;
475 		if (ret != want)
476 			goto out;
477 		seek = 0;
478 	} else {
479 		seek -= want;
480 		offset += want;
481 	}
482 
483 	want = xs_alloc_sparse_pages(
484 		buf, min_t(size_t, count - offset, buf->page_len),
485 		GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
486 	if (seek < want) {
487 		ret = xs_read_bvec(sock, msg, flags, buf->bvec,
488 				xdr_buf_pagecount(buf),
489 				want + buf->page_base,
490 				seek + buf->page_base);
491 		if (ret <= 0)
492 			goto sock_err;
493 		xs_flush_bvec(buf->bvec, ret, seek + buf->page_base);
494 		ret -= buf->page_base;
495 		offset += ret;
496 		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
497 			goto out;
498 		if (ret != want)
499 			goto out;
500 		seek = 0;
501 	} else {
502 		seek -= want;
503 		offset += want;
504 	}
505 
506 	want = min_t(size_t, count - offset, buf->tail[0].iov_len);
507 	if (seek < want) {
508 		ret = xs_read_kvec(sock, msg, flags, &buf->tail[0], want, seek);
509 		if (ret <= 0)
510 			goto sock_err;
511 		offset += ret;
512 		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
513 			goto out;
514 		if (ret != want)
515 			goto out;
516 	} else if (offset < seek_init)
517 		offset = seek_init;
518 	ret = -EMSGSIZE;
519 out:
520 	*read = offset - seek_init;
521 	return ret;
522 sock_err:
523 	offset += seek;
524 	goto out;
525 }
526 
527 static void
528 xs_read_header(struct sock_xprt *transport, struct xdr_buf *buf)
529 {
530 	if (!transport->recv.copied) {
531 		if (buf->head[0].iov_len >= transport->recv.offset)
532 			memcpy(buf->head[0].iov_base,
533 					&transport->recv.xid,
534 					transport->recv.offset);
535 		transport->recv.copied = transport->recv.offset;
536 	}
537 }
538 
539 static bool
540 xs_read_stream_request_done(struct sock_xprt *transport)
541 {
542 	return transport->recv.fraghdr & cpu_to_be32(RPC_LAST_STREAM_FRAGMENT);
543 }
544 
545 static void
546 xs_read_stream_check_eor(struct sock_xprt *transport,
547 		struct msghdr *msg)
548 {
549 	if (xs_read_stream_request_done(transport))
550 		msg->msg_flags |= MSG_EOR;
551 }
552 
553 static ssize_t
554 xs_read_stream_request(struct sock_xprt *transport, struct msghdr *msg,
555 		int flags, struct rpc_rqst *req)
556 {
557 	struct xdr_buf *buf = &req->rq_private_buf;
558 	size_t want, read;
559 	ssize_t ret;
560 
561 	xs_read_header(transport, buf);
562 
563 	want = transport->recv.len - transport->recv.offset;
564 	if (want != 0) {
565 		ret = xs_read_xdr_buf(transport->sock, msg, flags, buf,
566 				transport->recv.copied + want,
567 				transport->recv.copied,
568 				&read);
569 		transport->recv.offset += read;
570 		transport->recv.copied += read;
571 	}
572 
573 	if (transport->recv.offset == transport->recv.len)
574 		xs_read_stream_check_eor(transport, msg);
575 
576 	if (want == 0)
577 		return 0;
578 
579 	switch (ret) {
580 	default:
581 		break;
582 	case -EFAULT:
583 	case -EMSGSIZE:
584 		msg->msg_flags |= MSG_TRUNC;
585 		return read;
586 	case 0:
587 		return -ESHUTDOWN;
588 	}
589 	return ret < 0 ? ret : read;
590 }
591 
592 static size_t
593 xs_read_stream_headersize(bool isfrag)
594 {
595 	if (isfrag)
596 		return sizeof(__be32);
597 	return 3 * sizeof(__be32);
598 }
599 
600 static ssize_t
601 xs_read_stream_header(struct sock_xprt *transport, struct msghdr *msg,
602 		int flags, size_t want, size_t seek)
603 {
604 	struct kvec kvec = {
605 		.iov_base = &transport->recv.fraghdr,
606 		.iov_len = want,
607 	};
608 	return xs_read_kvec(transport->sock, msg, flags, &kvec, want, seek);
609 }
610 
611 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
612 static ssize_t
613 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
614 {
615 	struct rpc_xprt *xprt = &transport->xprt;
616 	struct rpc_rqst *req;
617 	ssize_t ret;
618 
619 	/* Is this transport associated with the backchannel? */
620 	if (!xprt->bc_serv)
621 		return -ESHUTDOWN;
622 
623 	/* Look up and lock the request corresponding to the given XID */
624 	req = xprt_lookup_bc_request(xprt, transport->recv.xid);
625 	if (!req) {
626 		printk(KERN_WARNING "Callback slot table overflowed\n");
627 		return -ESHUTDOWN;
628 	}
629 	if (transport->recv.copied && !req->rq_private_buf.len)
630 		return -ESHUTDOWN;
631 
632 	ret = xs_read_stream_request(transport, msg, flags, req);
633 	if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
634 		xprt_complete_bc_request(req, transport->recv.copied);
635 	else
636 		req->rq_private_buf.len = transport->recv.copied;
637 
638 	return ret;
639 }
640 #else /* CONFIG_SUNRPC_BACKCHANNEL */
641 static ssize_t
642 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
643 {
644 	return -ESHUTDOWN;
645 }
646 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
647 
648 static ssize_t
649 xs_read_stream_reply(struct sock_xprt *transport, struct msghdr *msg, int flags)
650 {
651 	struct rpc_xprt *xprt = &transport->xprt;
652 	struct rpc_rqst *req;
653 	ssize_t ret = 0;
654 
655 	/* Look up and lock the request corresponding to the given XID */
656 	spin_lock(&xprt->queue_lock);
657 	req = xprt_lookup_rqst(xprt, transport->recv.xid);
658 	if (!req || (transport->recv.copied && !req->rq_private_buf.len)) {
659 		msg->msg_flags |= MSG_TRUNC;
660 		goto out;
661 	}
662 	xprt_pin_rqst(req);
663 	spin_unlock(&xprt->queue_lock);
664 
665 	ret = xs_read_stream_request(transport, msg, flags, req);
666 
667 	spin_lock(&xprt->queue_lock);
668 	if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
669 		xprt_complete_rqst(req->rq_task, transport->recv.copied);
670 	else
671 		req->rq_private_buf.len = transport->recv.copied;
672 	xprt_unpin_rqst(req);
673 out:
674 	spin_unlock(&xprt->queue_lock);
675 	return ret;
676 }
677 
678 static ssize_t
679 xs_read_stream(struct sock_xprt *transport, int flags)
680 {
681 	struct msghdr msg = { 0 };
682 	size_t want, read = 0;
683 	ssize_t ret = 0;
684 
685 	if (transport->recv.len == 0) {
686 		want = xs_read_stream_headersize(transport->recv.copied != 0);
687 		ret = xs_read_stream_header(transport, &msg, flags, want,
688 				transport->recv.offset);
689 		if (ret <= 0)
690 			goto out_err;
691 		transport->recv.offset = ret;
692 		if (transport->recv.offset != want)
693 			return transport->recv.offset;
694 		transport->recv.len = be32_to_cpu(transport->recv.fraghdr) &
695 			RPC_FRAGMENT_SIZE_MASK;
696 		transport->recv.offset -= sizeof(transport->recv.fraghdr);
697 		read = ret;
698 	}
699 
700 	switch (be32_to_cpu(transport->recv.calldir)) {
701 	default:
702 		msg.msg_flags |= MSG_TRUNC;
703 		break;
704 	case RPC_CALL:
705 		ret = xs_read_stream_call(transport, &msg, flags);
706 		break;
707 	case RPC_REPLY:
708 		ret = xs_read_stream_reply(transport, &msg, flags);
709 	}
710 	if (msg.msg_flags & MSG_TRUNC) {
711 		transport->recv.calldir = cpu_to_be32(-1);
712 		transport->recv.copied = -1;
713 	}
714 	if (ret < 0)
715 		goto out_err;
716 	read += ret;
717 	if (transport->recv.offset < transport->recv.len) {
718 		if (!(msg.msg_flags & MSG_TRUNC))
719 			return read;
720 		msg.msg_flags = 0;
721 		ret = xs_read_discard(transport->sock, &msg, flags,
722 				transport->recv.len - transport->recv.offset);
723 		if (ret <= 0)
724 			goto out_err;
725 		transport->recv.offset += ret;
726 		read += ret;
727 		if (transport->recv.offset != transport->recv.len)
728 			return read;
729 	}
730 	if (xs_read_stream_request_done(transport)) {
731 		trace_xs_stream_read_request(transport);
732 		transport->recv.copied = 0;
733 	}
734 	transport->recv.offset = 0;
735 	transport->recv.len = 0;
736 	return read;
737 out_err:
738 	return ret != 0 ? ret : -ESHUTDOWN;
739 }
740 
741 static __poll_t xs_poll_socket(struct sock_xprt *transport)
742 {
743 	return transport->sock->ops->poll(transport->file, transport->sock,
744 			NULL);
745 }
746 
747 static bool xs_poll_socket_readable(struct sock_xprt *transport)
748 {
749 	__poll_t events = xs_poll_socket(transport);
750 
751 	return (events & (EPOLLIN | EPOLLRDNORM)) && !(events & EPOLLRDHUP);
752 }
753 
754 static void xs_poll_check_readable(struct sock_xprt *transport)
755 {
756 
757 	clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
758 	if (test_bit(XPRT_SOCK_IGNORE_RECV, &transport->sock_state))
759 		return;
760 	if (!xs_poll_socket_readable(transport))
761 		return;
762 	if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
763 		queue_work(xprtiod_workqueue, &transport->recv_worker);
764 }
765 
766 static void xs_stream_data_receive(struct sock_xprt *transport)
767 {
768 	size_t read = 0;
769 	ssize_t ret = 0;
770 
771 	mutex_lock(&transport->recv_mutex);
772 	if (transport->sock == NULL)
773 		goto out;
774 	for (;;) {
775 		ret = xs_read_stream(transport, MSG_DONTWAIT);
776 		if (ret < 0)
777 			break;
778 		read += ret;
779 		cond_resched();
780 	}
781 	if (ret == -ESHUTDOWN)
782 		kernel_sock_shutdown(transport->sock, SHUT_RDWR);
783 	else if (ret == -EACCES)
784 		xprt_wake_pending_tasks(&transport->xprt, -EACCES);
785 	else
786 		xs_poll_check_readable(transport);
787 out:
788 	mutex_unlock(&transport->recv_mutex);
789 	trace_xs_stream_read_data(&transport->xprt, ret, read);
790 }
791 
792 static void xs_stream_data_receive_workfn(struct work_struct *work)
793 {
794 	struct sock_xprt *transport =
795 		container_of(work, struct sock_xprt, recv_worker);
796 	unsigned int pflags = memalloc_nofs_save();
797 
798 	xs_stream_data_receive(transport);
799 	memalloc_nofs_restore(pflags);
800 }
801 
802 static void
803 xs_stream_reset_connect(struct sock_xprt *transport)
804 {
805 	transport->recv.offset = 0;
806 	transport->recv.len = 0;
807 	transport->recv.copied = 0;
808 	transport->xmit.offset = 0;
809 }
810 
811 static void
812 xs_stream_start_connect(struct sock_xprt *transport)
813 {
814 	transport->xprt.stat.connect_count++;
815 	transport->xprt.stat.connect_start = jiffies;
816 }
817 
818 #define XS_SENDMSG_FLAGS	(MSG_DONTWAIT | MSG_NOSIGNAL)
819 
820 /**
821  * xs_nospace - handle transmit was incomplete
822  * @req: pointer to RPC request
823  * @transport: pointer to struct sock_xprt
824  *
825  */
826 static int xs_nospace(struct rpc_rqst *req, struct sock_xprt *transport)
827 {
828 	struct rpc_xprt *xprt = &transport->xprt;
829 	struct sock *sk = transport->inet;
830 	int ret = -EAGAIN;
831 
832 	trace_rpc_socket_nospace(req, transport);
833 
834 	/* Protect against races with write_space */
835 	spin_lock(&xprt->transport_lock);
836 
837 	/* Don't race with disconnect */
838 	if (xprt_connected(xprt)) {
839 		/* wait for more buffer space */
840 		set_bit(XPRT_SOCK_NOSPACE, &transport->sock_state);
841 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
842 		sk->sk_write_pending++;
843 		xprt_wait_for_buffer_space(xprt);
844 	} else
845 		ret = -ENOTCONN;
846 
847 	spin_unlock(&xprt->transport_lock);
848 	return ret;
849 }
850 
851 static int xs_sock_nospace(struct rpc_rqst *req)
852 {
853 	struct sock_xprt *transport =
854 		container_of(req->rq_xprt, struct sock_xprt, xprt);
855 	struct sock *sk = transport->inet;
856 	int ret = -EAGAIN;
857 
858 	lock_sock(sk);
859 	if (!sock_writeable(sk))
860 		ret = xs_nospace(req, transport);
861 	release_sock(sk);
862 	return ret;
863 }
864 
865 static int xs_stream_nospace(struct rpc_rqst *req, bool vm_wait)
866 {
867 	struct sock_xprt *transport =
868 		container_of(req->rq_xprt, struct sock_xprt, xprt);
869 	struct sock *sk = transport->inet;
870 	int ret = -EAGAIN;
871 
872 	if (vm_wait)
873 		return -ENOBUFS;
874 	lock_sock(sk);
875 	if (!sk_stream_memory_free(sk))
876 		ret = xs_nospace(req, transport);
877 	release_sock(sk);
878 	return ret;
879 }
880 
881 static int xs_stream_prepare_request(struct rpc_rqst *req, struct xdr_buf *buf)
882 {
883 	return xdr_alloc_bvec(buf, rpc_task_gfp_mask());
884 }
885 
886 /*
887  * Determine if the previous message in the stream was aborted before it
888  * could complete transmission.
889  */
890 static bool
891 xs_send_request_was_aborted(struct sock_xprt *transport, struct rpc_rqst *req)
892 {
893 	return transport->xmit.offset != 0 && req->rq_bytes_sent == 0;
894 }
895 
896 /*
897  * Return the stream record marker field for a record of length < 2^31-1
898  */
899 static rpc_fraghdr
900 xs_stream_record_marker(struct xdr_buf *xdr)
901 {
902 	if (!xdr->len)
903 		return 0;
904 	return cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | (u32)xdr->len);
905 }
906 
907 /**
908  * xs_local_send_request - write an RPC request to an AF_LOCAL socket
909  * @req: pointer to RPC request
910  *
911  * Return values:
912  *        0:	The request has been sent
913  *   EAGAIN:	The socket was blocked, please call again later to
914  *		complete the request
915  * ENOTCONN:	Caller needs to invoke connect logic then call again
916  *    other:	Some other error occurred, the request was not sent
917  */
918 static int xs_local_send_request(struct rpc_rqst *req)
919 {
920 	struct rpc_xprt *xprt = req->rq_xprt;
921 	struct sock_xprt *transport =
922 				container_of(xprt, struct sock_xprt, xprt);
923 	struct xdr_buf *xdr = &req->rq_snd_buf;
924 	rpc_fraghdr rm = xs_stream_record_marker(xdr);
925 	unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
926 	struct msghdr msg = {
927 		.msg_flags	= XS_SENDMSG_FLAGS,
928 	};
929 	bool vm_wait;
930 	unsigned int sent;
931 	int status;
932 
933 	/* Close the stream if the previous transmission was incomplete */
934 	if (xs_send_request_was_aborted(transport, req)) {
935 		xprt_force_disconnect(xprt);
936 		return -ENOTCONN;
937 	}
938 
939 	xs_pktdump("packet data:",
940 			req->rq_svec->iov_base, req->rq_svec->iov_len);
941 
942 	vm_wait = sk_stream_is_writeable(transport->inet) ? true : false;
943 
944 	req->rq_xtime = ktime_get();
945 	status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
946 				   transport->xmit.offset, rm, &sent);
947 	dprintk("RPC:       %s(%u) = %d\n",
948 			__func__, xdr->len - transport->xmit.offset, status);
949 
950 	if (likely(sent > 0) || status == 0) {
951 		transport->xmit.offset += sent;
952 		req->rq_bytes_sent = transport->xmit.offset;
953 		if (likely(req->rq_bytes_sent >= msglen)) {
954 			req->rq_xmit_bytes_sent += transport->xmit.offset;
955 			transport->xmit.offset = 0;
956 			return 0;
957 		}
958 		status = -EAGAIN;
959 		vm_wait = false;
960 	}
961 
962 	switch (status) {
963 	case -EAGAIN:
964 		status = xs_stream_nospace(req, vm_wait);
965 		break;
966 	default:
967 		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
968 			-status);
969 		fallthrough;
970 	case -EPIPE:
971 		xprt_force_disconnect(xprt);
972 		status = -ENOTCONN;
973 	}
974 
975 	return status;
976 }
977 
978 /**
979  * xs_udp_send_request - write an RPC request to a UDP socket
980  * @req: pointer to RPC request
981  *
982  * Return values:
983  *        0:	The request has been sent
984  *   EAGAIN:	The socket was blocked, please call again later to
985  *		complete the request
986  * ENOTCONN:	Caller needs to invoke connect logic then call again
987  *    other:	Some other error occurred, the request was not sent
988  */
989 static int xs_udp_send_request(struct rpc_rqst *req)
990 {
991 	struct rpc_xprt *xprt = req->rq_xprt;
992 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
993 	struct xdr_buf *xdr = &req->rq_snd_buf;
994 	struct msghdr msg = {
995 		.msg_name	= xs_addr(xprt),
996 		.msg_namelen	= xprt->addrlen,
997 		.msg_flags	= XS_SENDMSG_FLAGS,
998 	};
999 	unsigned int sent;
1000 	int status;
1001 
1002 	xs_pktdump("packet data:",
1003 				req->rq_svec->iov_base,
1004 				req->rq_svec->iov_len);
1005 
1006 	if (!xprt_bound(xprt))
1007 		return -ENOTCONN;
1008 
1009 	if (!xprt_request_get_cong(xprt, req))
1010 		return -EBADSLT;
1011 
1012 	status = xdr_alloc_bvec(xdr, rpc_task_gfp_mask());
1013 	if (status < 0)
1014 		return status;
1015 	req->rq_xtime = ktime_get();
1016 	status = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, 0, &sent);
1017 
1018 	dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
1019 			xdr->len, status);
1020 
1021 	/* firewall is blocking us, don't return -EAGAIN or we end up looping */
1022 	if (status == -EPERM)
1023 		goto process_status;
1024 
1025 	if (status == -EAGAIN && sock_writeable(transport->inet))
1026 		status = -ENOBUFS;
1027 
1028 	if (sent > 0 || status == 0) {
1029 		req->rq_xmit_bytes_sent += sent;
1030 		if (sent >= req->rq_slen)
1031 			return 0;
1032 		/* Still some bytes left; set up for a retry later. */
1033 		status = -EAGAIN;
1034 	}
1035 
1036 process_status:
1037 	switch (status) {
1038 	case -ENOTSOCK:
1039 		status = -ENOTCONN;
1040 		/* Should we call xs_close() here? */
1041 		break;
1042 	case -EAGAIN:
1043 		status = xs_sock_nospace(req);
1044 		break;
1045 	case -ENETUNREACH:
1046 	case -ENOBUFS:
1047 	case -EPIPE:
1048 	case -ECONNREFUSED:
1049 	case -EPERM:
1050 		/* When the server has died, an ICMP port unreachable message
1051 		 * prompts ECONNREFUSED. */
1052 		break;
1053 	default:
1054 		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1055 			-status);
1056 	}
1057 
1058 	return status;
1059 }
1060 
1061 /**
1062  * xs_tcp_send_request - write an RPC request to a TCP socket
1063  * @req: pointer to RPC request
1064  *
1065  * Return values:
1066  *        0:	The request has been sent
1067  *   EAGAIN:	The socket was blocked, please call again later to
1068  *		complete the request
1069  * ENOTCONN:	Caller needs to invoke connect logic then call again
1070  *    other:	Some other error occurred, the request was not sent
1071  *
1072  * XXX: In the case of soft timeouts, should we eventually give up
1073  *	if sendmsg is not able to make progress?
1074  */
1075 static int xs_tcp_send_request(struct rpc_rqst *req)
1076 {
1077 	struct rpc_xprt *xprt = req->rq_xprt;
1078 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1079 	struct xdr_buf *xdr = &req->rq_snd_buf;
1080 	rpc_fraghdr rm = xs_stream_record_marker(xdr);
1081 	unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
1082 	struct msghdr msg = {
1083 		.msg_flags	= XS_SENDMSG_FLAGS,
1084 	};
1085 	bool vm_wait;
1086 	unsigned int sent;
1087 	int status;
1088 
1089 	/* Close the stream if the previous transmission was incomplete */
1090 	if (xs_send_request_was_aborted(transport, req)) {
1091 		if (transport->sock != NULL)
1092 			kernel_sock_shutdown(transport->sock, SHUT_RDWR);
1093 		return -ENOTCONN;
1094 	}
1095 	if (!transport->inet)
1096 		return -ENOTCONN;
1097 
1098 	xs_pktdump("packet data:",
1099 				req->rq_svec->iov_base,
1100 				req->rq_svec->iov_len);
1101 
1102 	if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state))
1103 		xs_tcp_set_socket_timeouts(xprt, transport->sock);
1104 
1105 	xs_set_srcport(transport, transport->sock);
1106 
1107 	/* Continue transmitting the packet/record. We must be careful
1108 	 * to cope with writespace callbacks arriving _after_ we have
1109 	 * called sendmsg(). */
1110 	req->rq_xtime = ktime_get();
1111 	tcp_sock_set_cork(transport->inet, true);
1112 
1113 	vm_wait = sk_stream_is_writeable(transport->inet) ? true : false;
1114 
1115 	do {
1116 		status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
1117 					   transport->xmit.offset, rm, &sent);
1118 
1119 		dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
1120 				xdr->len - transport->xmit.offset, status);
1121 
1122 		/* If we've sent the entire packet, immediately
1123 		 * reset the count of bytes sent. */
1124 		transport->xmit.offset += sent;
1125 		req->rq_bytes_sent = transport->xmit.offset;
1126 		if (likely(req->rq_bytes_sent >= msglen)) {
1127 			req->rq_xmit_bytes_sent += transport->xmit.offset;
1128 			transport->xmit.offset = 0;
1129 			if (atomic_long_read(&xprt->xmit_queuelen) == 1)
1130 				tcp_sock_set_cork(transport->inet, false);
1131 			return 0;
1132 		}
1133 
1134 		WARN_ON_ONCE(sent == 0 && status == 0);
1135 
1136 		if (sent > 0)
1137 			vm_wait = false;
1138 
1139 	} while (status == 0);
1140 
1141 	switch (status) {
1142 	case -ENOTSOCK:
1143 		status = -ENOTCONN;
1144 		/* Should we call xs_close() here? */
1145 		break;
1146 	case -EAGAIN:
1147 		status = xs_stream_nospace(req, vm_wait);
1148 		break;
1149 	case -ECONNRESET:
1150 	case -ECONNREFUSED:
1151 	case -ENOTCONN:
1152 	case -EADDRINUSE:
1153 	case -ENOBUFS:
1154 	case -EPIPE:
1155 		break;
1156 	default:
1157 		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1158 			-status);
1159 	}
1160 
1161 	return status;
1162 }
1163 
1164 static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1165 {
1166 	transport->old_data_ready = sk->sk_data_ready;
1167 	transport->old_state_change = sk->sk_state_change;
1168 	transport->old_write_space = sk->sk_write_space;
1169 	transport->old_error_report = sk->sk_error_report;
1170 }
1171 
1172 static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1173 {
1174 	sk->sk_data_ready = transport->old_data_ready;
1175 	sk->sk_state_change = transport->old_state_change;
1176 	sk->sk_write_space = transport->old_write_space;
1177 	sk->sk_error_report = transport->old_error_report;
1178 }
1179 
1180 static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
1181 {
1182 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1183 
1184 	transport->xprt_err = 0;
1185 	clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1186 	clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state);
1187 	clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state);
1188 	clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state);
1189 	clear_bit(XPRT_SOCK_NOSPACE, &transport->sock_state);
1190 }
1191 
1192 static void xs_run_error_worker(struct sock_xprt *transport, unsigned int nr)
1193 {
1194 	set_bit(nr, &transport->sock_state);
1195 	queue_work(xprtiod_workqueue, &transport->error_worker);
1196 }
1197 
1198 static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
1199 {
1200 	xprt->connect_cookie++;
1201 	smp_mb__before_atomic();
1202 	clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1203 	clear_bit(XPRT_CLOSING, &xprt->state);
1204 	xs_sock_reset_state_flags(xprt);
1205 	smp_mb__after_atomic();
1206 }
1207 
1208 /**
1209  * xs_error_report - callback to handle TCP socket state errors
1210  * @sk: socket
1211  *
1212  * Note: we don't call sock_error() since there may be a rpc_task
1213  * using the socket, and so we don't want to clear sk->sk_err.
1214  */
1215 static void xs_error_report(struct sock *sk)
1216 {
1217 	struct sock_xprt *transport;
1218 	struct rpc_xprt *xprt;
1219 
1220 	if (!(xprt = xprt_from_sock(sk)))
1221 		return;
1222 
1223 	transport = container_of(xprt, struct sock_xprt, xprt);
1224 	transport->xprt_err = -sk->sk_err;
1225 	if (transport->xprt_err == 0)
1226 		return;
1227 	dprintk("RPC:       xs_error_report client %p, error=%d...\n",
1228 			xprt, -transport->xprt_err);
1229 	trace_rpc_socket_error(xprt, sk->sk_socket, transport->xprt_err);
1230 
1231 	/* barrier ensures xprt_err is set before XPRT_SOCK_WAKE_ERROR */
1232 	smp_mb__before_atomic();
1233 	xs_run_error_worker(transport, XPRT_SOCK_WAKE_ERROR);
1234 }
1235 
1236 static void xs_reset_transport(struct sock_xprt *transport)
1237 {
1238 	struct socket *sock = transport->sock;
1239 	struct sock *sk = transport->inet;
1240 	struct rpc_xprt *xprt = &transport->xprt;
1241 	struct file *filp = transport->file;
1242 
1243 	if (sk == NULL)
1244 		return;
1245 	/*
1246 	 * Make sure we're calling this in a context from which it is safe
1247 	 * to call __fput_sync(). In practice that means rpciod and the
1248 	 * system workqueue.
1249 	 */
1250 	if (!(current->flags & PF_WQ_WORKER)) {
1251 		WARN_ON_ONCE(1);
1252 		set_bit(XPRT_CLOSE_WAIT, &xprt->state);
1253 		return;
1254 	}
1255 
1256 	if (atomic_read(&transport->xprt.swapper))
1257 		sk_clear_memalloc(sk);
1258 
1259 	tls_handshake_cancel(sk);
1260 
1261 	kernel_sock_shutdown(sock, SHUT_RDWR);
1262 
1263 	mutex_lock(&transport->recv_mutex);
1264 	lock_sock(sk);
1265 	transport->inet = NULL;
1266 	transport->sock = NULL;
1267 	transport->file = NULL;
1268 
1269 	sk->sk_user_data = NULL;
1270 
1271 	xs_restore_old_callbacks(transport, sk);
1272 	xprt_clear_connected(xprt);
1273 	xs_sock_reset_connection_flags(xprt);
1274 	/* Reset stream record info */
1275 	xs_stream_reset_connect(transport);
1276 	release_sock(sk);
1277 	mutex_unlock(&transport->recv_mutex);
1278 
1279 	trace_rpc_socket_close(xprt, sock);
1280 	__fput_sync(filp);
1281 
1282 	xprt_disconnect_done(xprt);
1283 }
1284 
1285 /**
1286  * xs_close - close a socket
1287  * @xprt: transport
1288  *
1289  * This is used when all requests are complete; ie, no DRC state remains
1290  * on the server we want to save.
1291  *
1292  * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
1293  * xs_reset_transport() zeroing the socket from underneath a writer.
1294  */
1295 static void xs_close(struct rpc_xprt *xprt)
1296 {
1297 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1298 
1299 	dprintk("RPC:       xs_close xprt %p\n", xprt);
1300 
1301 	if (transport->sock)
1302 		tls_handshake_close(transport->sock);
1303 	xs_reset_transport(transport);
1304 	xprt->reestablish_timeout = 0;
1305 }
1306 
1307 static void xs_inject_disconnect(struct rpc_xprt *xprt)
1308 {
1309 	dprintk("RPC:       injecting transport disconnect on xprt=%p\n",
1310 		xprt);
1311 	xprt_disconnect_done(xprt);
1312 }
1313 
1314 static void xs_xprt_free(struct rpc_xprt *xprt)
1315 {
1316 	xs_free_peer_addresses(xprt);
1317 	xprt_free(xprt);
1318 }
1319 
1320 /**
1321  * xs_destroy - prepare to shutdown a transport
1322  * @xprt: doomed transport
1323  *
1324  */
1325 static void xs_destroy(struct rpc_xprt *xprt)
1326 {
1327 	struct sock_xprt *transport = container_of(xprt,
1328 			struct sock_xprt, xprt);
1329 	dprintk("RPC:       xs_destroy xprt %p\n", xprt);
1330 
1331 	cancel_delayed_work_sync(&transport->connect_worker);
1332 	xs_close(xprt);
1333 	cancel_work_sync(&transport->recv_worker);
1334 	cancel_work_sync(&transport->error_worker);
1335 	xs_xprt_free(xprt);
1336 	module_put(THIS_MODULE);
1337 }
1338 
1339 /**
1340  * xs_udp_data_read_skb - receive callback for UDP sockets
1341  * @xprt: transport
1342  * @sk: socket
1343  * @skb: skbuff
1344  *
1345  */
1346 static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
1347 		struct sock *sk,
1348 		struct sk_buff *skb)
1349 {
1350 	struct rpc_task *task;
1351 	struct rpc_rqst *rovr;
1352 	int repsize, copied;
1353 	u32 _xid;
1354 	__be32 *xp;
1355 
1356 	repsize = skb->len;
1357 	if (repsize < 4) {
1358 		dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
1359 		return;
1360 	}
1361 
1362 	/* Copy the XID from the skb... */
1363 	xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
1364 	if (xp == NULL)
1365 		return;
1366 
1367 	/* Look up and lock the request corresponding to the given XID */
1368 	spin_lock(&xprt->queue_lock);
1369 	rovr = xprt_lookup_rqst(xprt, *xp);
1370 	if (!rovr)
1371 		goto out_unlock;
1372 	xprt_pin_rqst(rovr);
1373 	xprt_update_rtt(rovr->rq_task);
1374 	spin_unlock(&xprt->queue_lock);
1375 	task = rovr->rq_task;
1376 
1377 	if ((copied = rovr->rq_private_buf.buflen) > repsize)
1378 		copied = repsize;
1379 
1380 	/* Suck it into the iovec, verify checksum if not done by hw. */
1381 	if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1382 		spin_lock(&xprt->queue_lock);
1383 		__UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
1384 		goto out_unpin;
1385 	}
1386 
1387 
1388 	spin_lock(&xprt->transport_lock);
1389 	xprt_adjust_cwnd(xprt, task, copied);
1390 	spin_unlock(&xprt->transport_lock);
1391 	spin_lock(&xprt->queue_lock);
1392 	xprt_complete_rqst(task, copied);
1393 	__UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
1394 out_unpin:
1395 	xprt_unpin_rqst(rovr);
1396  out_unlock:
1397 	spin_unlock(&xprt->queue_lock);
1398 }
1399 
1400 static void xs_udp_data_receive(struct sock_xprt *transport)
1401 {
1402 	struct sk_buff *skb;
1403 	struct sock *sk;
1404 	int err;
1405 
1406 	mutex_lock(&transport->recv_mutex);
1407 	sk = transport->inet;
1408 	if (sk == NULL)
1409 		goto out;
1410 	for (;;) {
1411 		skb = skb_recv_udp(sk, MSG_DONTWAIT, &err);
1412 		if (skb == NULL)
1413 			break;
1414 		xs_udp_data_read_skb(&transport->xprt, sk, skb);
1415 		consume_skb(skb);
1416 		cond_resched();
1417 	}
1418 	xs_poll_check_readable(transport);
1419 out:
1420 	mutex_unlock(&transport->recv_mutex);
1421 }
1422 
1423 static void xs_udp_data_receive_workfn(struct work_struct *work)
1424 {
1425 	struct sock_xprt *transport =
1426 		container_of(work, struct sock_xprt, recv_worker);
1427 	unsigned int pflags = memalloc_nofs_save();
1428 
1429 	xs_udp_data_receive(transport);
1430 	memalloc_nofs_restore(pflags);
1431 }
1432 
1433 /**
1434  * xs_data_ready - "data ready" callback for sockets
1435  * @sk: socket with data to read
1436  *
1437  */
1438 static void xs_data_ready(struct sock *sk)
1439 {
1440 	struct rpc_xprt *xprt;
1441 
1442 	trace_sk_data_ready(sk);
1443 
1444 	xprt = xprt_from_sock(sk);
1445 	if (xprt != NULL) {
1446 		struct sock_xprt *transport = container_of(xprt,
1447 				struct sock_xprt, xprt);
1448 
1449 		trace_xs_data_ready(xprt);
1450 
1451 		transport->old_data_ready(sk);
1452 
1453 		if (test_bit(XPRT_SOCK_IGNORE_RECV, &transport->sock_state))
1454 			return;
1455 
1456 		/* Any data means we had a useful conversation, so
1457 		 * then we don't need to delay the next reconnect
1458 		 */
1459 		if (xprt->reestablish_timeout)
1460 			xprt->reestablish_timeout = 0;
1461 		if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1462 			queue_work(xprtiod_workqueue, &transport->recv_worker);
1463 	}
1464 }
1465 
1466 /*
1467  * Helper function to force a TCP close if the server is sending
1468  * junk and/or it has put us in CLOSE_WAIT
1469  */
1470 static void xs_tcp_force_close(struct rpc_xprt *xprt)
1471 {
1472 	xprt_force_disconnect(xprt);
1473 }
1474 
1475 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1476 static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
1477 {
1478 	return PAGE_SIZE;
1479 }
1480 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1481 
1482 /**
1483  * xs_local_state_change - callback to handle AF_LOCAL socket state changes
1484  * @sk: socket whose state has changed
1485  *
1486  */
1487 static void xs_local_state_change(struct sock *sk)
1488 {
1489 	struct rpc_xprt *xprt;
1490 	struct sock_xprt *transport;
1491 
1492 	if (!(xprt = xprt_from_sock(sk)))
1493 		return;
1494 	transport = container_of(xprt, struct sock_xprt, xprt);
1495 	if (sk->sk_shutdown & SHUTDOWN_MASK) {
1496 		clear_bit(XPRT_CONNECTED, &xprt->state);
1497 		/* Trigger the socket release */
1498 		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1499 	}
1500 }
1501 
1502 /**
1503  * xs_tcp_state_change - callback to handle TCP socket state changes
1504  * @sk: socket whose state has changed
1505  *
1506  */
1507 static void xs_tcp_state_change(struct sock *sk)
1508 {
1509 	struct rpc_xprt *xprt;
1510 	struct sock_xprt *transport;
1511 
1512 	if (!(xprt = xprt_from_sock(sk)))
1513 		return;
1514 	dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1515 	dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1516 			sk->sk_state, xprt_connected(xprt),
1517 			sock_flag(sk, SOCK_DEAD),
1518 			sock_flag(sk, SOCK_ZAPPED),
1519 			sk->sk_shutdown);
1520 
1521 	transport = container_of(xprt, struct sock_xprt, xprt);
1522 	trace_rpc_socket_state_change(xprt, sk->sk_socket);
1523 	switch (sk->sk_state) {
1524 	case TCP_ESTABLISHED:
1525 		if (!xprt_test_and_set_connected(xprt)) {
1526 			xprt->connect_cookie++;
1527 			clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
1528 			xprt_clear_connecting(xprt);
1529 
1530 			xprt->stat.connect_count++;
1531 			xprt->stat.connect_time += (long)jiffies -
1532 						   xprt->stat.connect_start;
1533 			xs_run_error_worker(transport, XPRT_SOCK_WAKE_PENDING);
1534 		}
1535 		break;
1536 	case TCP_FIN_WAIT1:
1537 		/* The client initiated a shutdown of the socket */
1538 		xprt->connect_cookie++;
1539 		xprt->reestablish_timeout = 0;
1540 		set_bit(XPRT_CLOSING, &xprt->state);
1541 		smp_mb__before_atomic();
1542 		clear_bit(XPRT_CONNECTED, &xprt->state);
1543 		clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1544 		smp_mb__after_atomic();
1545 		break;
1546 	case TCP_CLOSE_WAIT:
1547 		/* The server initiated a shutdown of the socket */
1548 		xprt->connect_cookie++;
1549 		clear_bit(XPRT_CONNECTED, &xprt->state);
1550 		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1551 		fallthrough;
1552 	case TCP_CLOSING:
1553 		/*
1554 		 * If the server closed down the connection, make sure that
1555 		 * we back off before reconnecting
1556 		 */
1557 		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1558 			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1559 		break;
1560 	case TCP_LAST_ACK:
1561 		set_bit(XPRT_CLOSING, &xprt->state);
1562 		smp_mb__before_atomic();
1563 		clear_bit(XPRT_CONNECTED, &xprt->state);
1564 		smp_mb__after_atomic();
1565 		break;
1566 	case TCP_CLOSE:
1567 		if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
1568 					&transport->sock_state))
1569 			xprt_clear_connecting(xprt);
1570 		clear_bit(XPRT_CLOSING, &xprt->state);
1571 		/* Trigger the socket release */
1572 		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1573 	}
1574 }
1575 
1576 static void xs_write_space(struct sock *sk)
1577 {
1578 	struct sock_xprt *transport;
1579 	struct rpc_xprt *xprt;
1580 
1581 	if (!sk->sk_socket)
1582 		return;
1583 	clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1584 
1585 	if (unlikely(!(xprt = xprt_from_sock(sk))))
1586 		return;
1587 	transport = container_of(xprt, struct sock_xprt, xprt);
1588 	if (!test_and_clear_bit(XPRT_SOCK_NOSPACE, &transport->sock_state))
1589 		return;
1590 	xs_run_error_worker(transport, XPRT_SOCK_WAKE_WRITE);
1591 	sk->sk_write_pending--;
1592 }
1593 
1594 /**
1595  * xs_udp_write_space - callback invoked when socket buffer space
1596  *                             becomes available
1597  * @sk: socket whose state has changed
1598  *
1599  * Called when more output buffer space is available for this socket.
1600  * We try not to wake our writers until they can make "significant"
1601  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1602  * with a bunch of small requests.
1603  */
1604 static void xs_udp_write_space(struct sock *sk)
1605 {
1606 	/* from net/core/sock.c:sock_def_write_space */
1607 	if (sock_writeable(sk))
1608 		xs_write_space(sk);
1609 }
1610 
1611 /**
1612  * xs_tcp_write_space - callback invoked when socket buffer space
1613  *                             becomes available
1614  * @sk: socket whose state has changed
1615  *
1616  * Called when more output buffer space is available for this socket.
1617  * We try not to wake our writers until they can make "significant"
1618  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1619  * with a bunch of small requests.
1620  */
1621 static void xs_tcp_write_space(struct sock *sk)
1622 {
1623 	/* from net/core/stream.c:sk_stream_write_space */
1624 	if (sk_stream_is_writeable(sk))
1625 		xs_write_space(sk);
1626 }
1627 
1628 static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1629 {
1630 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1631 	struct sock *sk = transport->inet;
1632 
1633 	if (transport->rcvsize) {
1634 		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1635 		sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1636 	}
1637 	if (transport->sndsize) {
1638 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1639 		sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1640 		sk->sk_write_space(sk);
1641 	}
1642 }
1643 
1644 /**
1645  * xs_udp_set_buffer_size - set send and receive limits
1646  * @xprt: generic transport
1647  * @sndsize: requested size of send buffer, in bytes
1648  * @rcvsize: requested size of receive buffer, in bytes
1649  *
1650  * Set socket send and receive buffer size limits.
1651  */
1652 static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1653 {
1654 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1655 
1656 	transport->sndsize = 0;
1657 	if (sndsize)
1658 		transport->sndsize = sndsize + 1024;
1659 	transport->rcvsize = 0;
1660 	if (rcvsize)
1661 		transport->rcvsize = rcvsize + 1024;
1662 
1663 	xs_udp_do_set_buffer_size(xprt);
1664 }
1665 
1666 /**
1667  * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1668  * @xprt: controlling transport
1669  * @task: task that timed out
1670  *
1671  * Adjust the congestion window after a retransmit timeout has occurred.
1672  */
1673 static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1674 {
1675 	spin_lock(&xprt->transport_lock);
1676 	xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1677 	spin_unlock(&xprt->transport_lock);
1678 }
1679 
1680 static int xs_get_random_port(void)
1681 {
1682 	unsigned short min = xprt_min_resvport, max = xprt_max_resvport;
1683 	unsigned short range;
1684 	unsigned short rand;
1685 
1686 	if (max < min)
1687 		return -EADDRINUSE;
1688 	range = max - min + 1;
1689 	rand = get_random_u32_below(range);
1690 	return rand + min;
1691 }
1692 
1693 static unsigned short xs_sock_getport(struct socket *sock)
1694 {
1695 	struct sockaddr_storage buf;
1696 	unsigned short port = 0;
1697 
1698 	if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0)
1699 		goto out;
1700 	switch (buf.ss_family) {
1701 	case AF_INET6:
1702 		port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1703 		break;
1704 	case AF_INET:
1705 		port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1706 	}
1707 out:
1708 	return port;
1709 }
1710 
1711 /**
1712  * xs_set_port - reset the port number in the remote endpoint address
1713  * @xprt: generic transport
1714  * @port: new port number
1715  *
1716  */
1717 static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1718 {
1719 	dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1720 
1721 	rpc_set_port(xs_addr(xprt), port);
1722 	xs_update_peer_port(xprt);
1723 }
1724 
1725 static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1726 {
1727 	if (transport->srcport == 0 && transport->xprt.reuseport)
1728 		transport->srcport = xs_sock_getport(sock);
1729 }
1730 
1731 static int xs_get_srcport(struct sock_xprt *transport)
1732 {
1733 	int port = transport->srcport;
1734 
1735 	if (port == 0 && transport->xprt.resvport)
1736 		port = xs_get_random_port();
1737 	return port;
1738 }
1739 
1740 static unsigned short xs_sock_srcport(struct rpc_xprt *xprt)
1741 {
1742 	struct sock_xprt *sock = container_of(xprt, struct sock_xprt, xprt);
1743 	unsigned short ret = 0;
1744 	mutex_lock(&sock->recv_mutex);
1745 	if (sock->sock)
1746 		ret = xs_sock_getport(sock->sock);
1747 	mutex_unlock(&sock->recv_mutex);
1748 	return ret;
1749 }
1750 
1751 static int xs_sock_srcaddr(struct rpc_xprt *xprt, char *buf, size_t buflen)
1752 {
1753 	struct sock_xprt *sock = container_of(xprt, struct sock_xprt, xprt);
1754 	union {
1755 		struct sockaddr sa;
1756 		struct sockaddr_storage st;
1757 	} saddr;
1758 	int ret = -ENOTCONN;
1759 
1760 	mutex_lock(&sock->recv_mutex);
1761 	if (sock->sock) {
1762 		ret = kernel_getsockname(sock->sock, &saddr.sa);
1763 		if (ret >= 0)
1764 			ret = snprintf(buf, buflen, "%pISc", &saddr.sa);
1765 	}
1766 	mutex_unlock(&sock->recv_mutex);
1767 	return ret;
1768 }
1769 
1770 static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1771 {
1772 	if (transport->srcport != 0)
1773 		transport->srcport = 0;
1774 	if (!transport->xprt.resvport)
1775 		return 0;
1776 	if (port <= xprt_min_resvport || port > xprt_max_resvport)
1777 		return xprt_max_resvport;
1778 	return --port;
1779 }
1780 static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1781 {
1782 	struct sockaddr_storage myaddr;
1783 	int err, nloop = 0;
1784 	int port = xs_get_srcport(transport);
1785 	unsigned short last;
1786 
1787 	/*
1788 	 * If we are asking for any ephemeral port (i.e. port == 0 &&
1789 	 * transport->xprt.resvport == 0), don't bind.  Let the local
1790 	 * port selection happen implicitly when the socket is used
1791 	 * (for example at connect time).
1792 	 *
1793 	 * This ensures that we can continue to establish TCP
1794 	 * connections even when all local ephemeral ports are already
1795 	 * a part of some TCP connection.  This makes no difference
1796 	 * for UDP sockets, but also doesn't harm them.
1797 	 *
1798 	 * If we're asking for any reserved port (i.e. port == 0 &&
1799 	 * transport->xprt.resvport == 1) xs_get_srcport above will
1800 	 * ensure that port is non-zero and we will bind as needed.
1801 	 */
1802 	if (port <= 0)
1803 		return port;
1804 
1805 	memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1806 	do {
1807 		rpc_set_port((struct sockaddr *)&myaddr, port);
1808 		err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1809 				transport->xprt.addrlen);
1810 		if (err == 0) {
1811 			if (transport->xprt.reuseport)
1812 				transport->srcport = port;
1813 			break;
1814 		}
1815 		last = port;
1816 		port = xs_next_srcport(transport, port);
1817 		if (port > last)
1818 			nloop++;
1819 	} while (err == -EADDRINUSE && nloop != 2);
1820 
1821 	if (myaddr.ss_family == AF_INET)
1822 		dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1823 				&((struct sockaddr_in *)&myaddr)->sin_addr,
1824 				port, err ? "failed" : "ok", err);
1825 	else
1826 		dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1827 				&((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1828 				port, err ? "failed" : "ok", err);
1829 	return err;
1830 }
1831 
1832 /*
1833  * We don't support autobind on AF_LOCAL sockets
1834  */
1835 static void xs_local_rpcbind(struct rpc_task *task)
1836 {
1837 	xprt_set_bound(task->tk_xprt);
1838 }
1839 
1840 static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1841 {
1842 }
1843 
1844 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1845 static struct lock_class_key xs_key[3];
1846 static struct lock_class_key xs_slock_key[3];
1847 
1848 static inline void xs_reclassify_socketu(struct socket *sock)
1849 {
1850 	struct sock *sk = sock->sk;
1851 
1852 	sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1853 		&xs_slock_key[0], "sk_lock-AF_LOCAL-RPC", &xs_key[0]);
1854 }
1855 
1856 static inline void xs_reclassify_socket4(struct socket *sock)
1857 {
1858 	struct sock *sk = sock->sk;
1859 
1860 	sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1861 		&xs_slock_key[1], "sk_lock-AF_INET-RPC", &xs_key[1]);
1862 }
1863 
1864 static inline void xs_reclassify_socket6(struct socket *sock)
1865 {
1866 	struct sock *sk = sock->sk;
1867 
1868 	sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1869 		&xs_slock_key[2], "sk_lock-AF_INET6-RPC", &xs_key[2]);
1870 }
1871 
1872 static inline void xs_reclassify_socket(int family, struct socket *sock)
1873 {
1874 	if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
1875 		return;
1876 
1877 	switch (family) {
1878 	case AF_LOCAL:
1879 		xs_reclassify_socketu(sock);
1880 		break;
1881 	case AF_INET:
1882 		xs_reclassify_socket4(sock);
1883 		break;
1884 	case AF_INET6:
1885 		xs_reclassify_socket6(sock);
1886 		break;
1887 	}
1888 }
1889 #else
1890 static inline void xs_reclassify_socket(int family, struct socket *sock)
1891 {
1892 }
1893 #endif
1894 
1895 static void xs_dummy_setup_socket(struct work_struct *work)
1896 {
1897 }
1898 
1899 static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1900 		struct sock_xprt *transport, int family, int type,
1901 		int protocol, bool reuseport)
1902 {
1903 	struct file *filp;
1904 	struct socket *sock;
1905 	int err;
1906 
1907 	err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1908 	if (err < 0) {
1909 		dprintk("RPC:       can't create %d transport socket (%d).\n",
1910 				protocol, -err);
1911 		goto out;
1912 	}
1913 	xs_reclassify_socket(family, sock);
1914 
1915 	if (reuseport)
1916 		sock_set_reuseport(sock->sk);
1917 
1918 	err = xs_bind(transport, sock);
1919 	if (err) {
1920 		sock_release(sock);
1921 		goto out;
1922 	}
1923 
1924 	filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1925 	if (IS_ERR(filp))
1926 		return ERR_CAST(filp);
1927 	transport->file = filp;
1928 
1929 	return sock;
1930 out:
1931 	return ERR_PTR(err);
1932 }
1933 
1934 static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1935 				      struct socket *sock)
1936 {
1937 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1938 									xprt);
1939 
1940 	if (!transport->inet) {
1941 		struct sock *sk = sock->sk;
1942 
1943 		lock_sock(sk);
1944 
1945 		xs_save_old_callbacks(transport, sk);
1946 
1947 		sk->sk_user_data = xprt;
1948 		sk->sk_data_ready = xs_data_ready;
1949 		sk->sk_write_space = xs_udp_write_space;
1950 		sk->sk_state_change = xs_local_state_change;
1951 		sk->sk_error_report = xs_error_report;
1952 		sk->sk_use_task_frag = false;
1953 
1954 		xprt_clear_connected(xprt);
1955 
1956 		/* Reset to new socket */
1957 		transport->sock = sock;
1958 		transport->inet = sk;
1959 
1960 		release_sock(sk);
1961 	}
1962 
1963 	xs_stream_start_connect(transport);
1964 
1965 	return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1966 }
1967 
1968 /**
1969  * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1970  * @transport: socket transport to connect
1971  */
1972 static int xs_local_setup_socket(struct sock_xprt *transport)
1973 {
1974 	struct rpc_xprt *xprt = &transport->xprt;
1975 	struct file *filp;
1976 	struct socket *sock;
1977 	int status;
1978 
1979 	status = __sock_create(xprt->xprt_net, AF_LOCAL,
1980 					SOCK_STREAM, 0, &sock, 1);
1981 	if (status < 0) {
1982 		dprintk("RPC:       can't create AF_LOCAL "
1983 			"transport socket (%d).\n", -status);
1984 		goto out;
1985 	}
1986 	xs_reclassify_socket(AF_LOCAL, sock);
1987 
1988 	filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1989 	if (IS_ERR(filp)) {
1990 		status = PTR_ERR(filp);
1991 		goto out;
1992 	}
1993 	transport->file = filp;
1994 
1995 	dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
1996 			xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1997 
1998 	status = xs_local_finish_connecting(xprt, sock);
1999 	trace_rpc_socket_connect(xprt, sock, status);
2000 	switch (status) {
2001 	case 0:
2002 		dprintk("RPC:       xprt %p connected to %s\n",
2003 				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2004 		xprt->stat.connect_count++;
2005 		xprt->stat.connect_time += (long)jiffies -
2006 					   xprt->stat.connect_start;
2007 		xprt_set_connected(xprt);
2008 		break;
2009 	case -ENOBUFS:
2010 		break;
2011 	case -ENOENT:
2012 		dprintk("RPC:       xprt %p: socket %s does not exist\n",
2013 				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2014 		break;
2015 	case -ECONNREFUSED:
2016 		dprintk("RPC:       xprt %p: connection refused for %s\n",
2017 				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2018 		break;
2019 	default:
2020 		printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
2021 				__func__, -status,
2022 				xprt->address_strings[RPC_DISPLAY_ADDR]);
2023 	}
2024 
2025 out:
2026 	xprt_clear_connecting(xprt);
2027 	xprt_wake_pending_tasks(xprt, status);
2028 	return status;
2029 }
2030 
2031 static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2032 {
2033 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2034 	int ret;
2035 
2036 	if (transport->file)
2037 		goto force_disconnect;
2038 
2039 	if (RPC_IS_ASYNC(task)) {
2040 		/*
2041 		 * We want the AF_LOCAL connect to be resolved in the
2042 		 * filesystem namespace of the process making the rpc
2043 		 * call.  Thus we connect synchronously.
2044 		 *
2045 		 * If we want to support asynchronous AF_LOCAL calls,
2046 		 * we'll need to figure out how to pass a namespace to
2047 		 * connect.
2048 		 */
2049 		rpc_task_set_rpc_status(task, -ENOTCONN);
2050 		goto out_wake;
2051 	}
2052 	ret = xs_local_setup_socket(transport);
2053 	if (ret && !RPC_IS_SOFTCONN(task))
2054 		msleep_interruptible(15000);
2055 	return;
2056 force_disconnect:
2057 	xprt_force_disconnect(xprt);
2058 out_wake:
2059 	xprt_clear_connecting(xprt);
2060 	xprt_wake_pending_tasks(xprt, -ENOTCONN);
2061 }
2062 
2063 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
2064 /*
2065  * Note that this should be called with XPRT_LOCKED held, or recv_mutex
2066  * held, or when we otherwise know that we have exclusive access to the
2067  * socket, to guard against races with xs_reset_transport.
2068  */
2069 static void xs_set_memalloc(struct rpc_xprt *xprt)
2070 {
2071 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
2072 			xprt);
2073 
2074 	/*
2075 	 * If there's no sock, then we have nothing to set. The
2076 	 * reconnecting process will get it for us.
2077 	 */
2078 	if (!transport->inet)
2079 		return;
2080 	if (atomic_read(&xprt->swapper))
2081 		sk_set_memalloc(transport->inet);
2082 }
2083 
2084 /**
2085  * xs_enable_swap - Tag this transport as being used for swap.
2086  * @xprt: transport to tag
2087  *
2088  * Take a reference to this transport on behalf of the rpc_clnt, and
2089  * optionally mark it for swapping if it wasn't already.
2090  */
2091 static int
2092 xs_enable_swap(struct rpc_xprt *xprt)
2093 {
2094 	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2095 
2096 	mutex_lock(&xs->recv_mutex);
2097 	if (atomic_inc_return(&xprt->swapper) == 1 &&
2098 	    xs->inet)
2099 		sk_set_memalloc(xs->inet);
2100 	mutex_unlock(&xs->recv_mutex);
2101 	return 0;
2102 }
2103 
2104 /**
2105  * xs_disable_swap - Untag this transport as being used for swap.
2106  * @xprt: transport to tag
2107  *
2108  * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
2109  * swapper refcount goes to 0, untag the socket as a memalloc socket.
2110  */
2111 static void
2112 xs_disable_swap(struct rpc_xprt *xprt)
2113 {
2114 	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2115 
2116 	mutex_lock(&xs->recv_mutex);
2117 	if (atomic_dec_and_test(&xprt->swapper) &&
2118 	    xs->inet)
2119 		sk_clear_memalloc(xs->inet);
2120 	mutex_unlock(&xs->recv_mutex);
2121 }
2122 #else
2123 static void xs_set_memalloc(struct rpc_xprt *xprt)
2124 {
2125 }
2126 
2127 static int
2128 xs_enable_swap(struct rpc_xprt *xprt)
2129 {
2130 	return -EINVAL;
2131 }
2132 
2133 static void
2134 xs_disable_swap(struct rpc_xprt *xprt)
2135 {
2136 }
2137 #endif
2138 
2139 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2140 {
2141 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2142 
2143 	if (!transport->inet) {
2144 		struct sock *sk = sock->sk;
2145 
2146 		lock_sock(sk);
2147 
2148 		xs_save_old_callbacks(transport, sk);
2149 
2150 		sk->sk_user_data = xprt;
2151 		sk->sk_data_ready = xs_data_ready;
2152 		sk->sk_write_space = xs_udp_write_space;
2153 		sk->sk_use_task_frag = false;
2154 
2155 		xprt_set_connected(xprt);
2156 
2157 		/* Reset to new socket */
2158 		transport->sock = sock;
2159 		transport->inet = sk;
2160 
2161 		xs_set_memalloc(xprt);
2162 
2163 		release_sock(sk);
2164 	}
2165 	xs_udp_do_set_buffer_size(xprt);
2166 
2167 	xprt->stat.connect_start = jiffies;
2168 }
2169 
2170 static void xs_udp_setup_socket(struct work_struct *work)
2171 {
2172 	struct sock_xprt *transport =
2173 		container_of(work, struct sock_xprt, connect_worker.work);
2174 	struct rpc_xprt *xprt = &transport->xprt;
2175 	struct socket *sock;
2176 	int status = -EIO;
2177 	unsigned int pflags = current->flags;
2178 
2179 	if (atomic_read(&xprt->swapper))
2180 		current->flags |= PF_MEMALLOC;
2181 	sock = xs_create_sock(xprt, transport,
2182 			xs_addr(xprt)->sa_family, SOCK_DGRAM,
2183 			IPPROTO_UDP, false);
2184 	if (IS_ERR(sock))
2185 		goto out;
2186 
2187 	dprintk("RPC:       worker connecting xprt %p via %s to "
2188 				"%s (port %s)\n", xprt,
2189 			xprt->address_strings[RPC_DISPLAY_PROTO],
2190 			xprt->address_strings[RPC_DISPLAY_ADDR],
2191 			xprt->address_strings[RPC_DISPLAY_PORT]);
2192 
2193 	xs_udp_finish_connecting(xprt, sock);
2194 	trace_rpc_socket_connect(xprt, sock, 0);
2195 	status = 0;
2196 out:
2197 	xprt_clear_connecting(xprt);
2198 	xprt_unlock_connect(xprt, transport);
2199 	xprt_wake_pending_tasks(xprt, status);
2200 	current_restore_flags(pflags, PF_MEMALLOC);
2201 }
2202 
2203 /**
2204  * xs_tcp_shutdown - gracefully shut down a TCP socket
2205  * @xprt: transport
2206  *
2207  * Initiates a graceful shutdown of the TCP socket by calling the
2208  * equivalent of shutdown(SHUT_RDWR);
2209  */
2210 static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2211 {
2212 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2213 	struct socket *sock = transport->sock;
2214 	int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
2215 
2216 	if (sock == NULL)
2217 		return;
2218 	if (!xprt->reuseport) {
2219 		xs_close(xprt);
2220 		return;
2221 	}
2222 	switch (skst) {
2223 	case TCP_FIN_WAIT1:
2224 	case TCP_FIN_WAIT2:
2225 	case TCP_LAST_ACK:
2226 		break;
2227 	case TCP_ESTABLISHED:
2228 	case TCP_CLOSE_WAIT:
2229 		kernel_sock_shutdown(sock, SHUT_RDWR);
2230 		trace_rpc_socket_shutdown(xprt, sock);
2231 		break;
2232 	default:
2233 		xs_reset_transport(transport);
2234 	}
2235 }
2236 
2237 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
2238 		struct socket *sock)
2239 {
2240 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2241 	struct net *net = sock_net(sock->sk);
2242 	unsigned long connect_timeout;
2243 	unsigned long syn_retries;
2244 	unsigned int keepidle;
2245 	unsigned int keepcnt;
2246 	unsigned int timeo;
2247 	unsigned long t;
2248 
2249 	spin_lock(&xprt->transport_lock);
2250 	keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
2251 	keepcnt = xprt->timeout->to_retries + 1;
2252 	timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2253 		(xprt->timeout->to_retries + 1);
2254 	clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2255 	spin_unlock(&xprt->transport_lock);
2256 
2257 	/* TCP Keepalive options */
2258 	sock_set_keepalive(sock->sk);
2259 	tcp_sock_set_keepidle(sock->sk, keepidle);
2260 	tcp_sock_set_keepintvl(sock->sk, keepidle);
2261 	tcp_sock_set_keepcnt(sock->sk, keepcnt);
2262 
2263 	/* TCP user timeout (see RFC5482) */
2264 	tcp_sock_set_user_timeout(sock->sk, timeo);
2265 
2266 	/* Connect timeout */
2267 	connect_timeout = max_t(unsigned long,
2268 				DIV_ROUND_UP(xprt->connect_timeout, HZ), 1);
2269 	syn_retries = max_t(unsigned long,
2270 			    READ_ONCE(net->ipv4.sysctl_tcp_syn_retries), 1);
2271 	for (t = 0; t <= syn_retries && (1UL << t) < connect_timeout; t++)
2272 		;
2273 	if (t <= syn_retries)
2274 		tcp_sock_set_syncnt(sock->sk, t - 1);
2275 }
2276 
2277 static void xs_tcp_do_set_connect_timeout(struct rpc_xprt *xprt,
2278 					  unsigned long connect_timeout)
2279 {
2280 	struct sock_xprt *transport =
2281 		container_of(xprt, struct sock_xprt, xprt);
2282 	struct rpc_timeout to;
2283 	unsigned long initval;
2284 
2285 	memcpy(&to, xprt->timeout, sizeof(to));
2286 	/* Arbitrary lower limit */
2287 	initval = max_t(unsigned long, connect_timeout, XS_TCP_INIT_REEST_TO);
2288 	to.to_initval = initval;
2289 	to.to_maxval = initval;
2290 	to.to_retries = 0;
2291 	memcpy(&transport->tcp_timeout, &to, sizeof(transport->tcp_timeout));
2292 	xprt->timeout = &transport->tcp_timeout;
2293 	xprt->connect_timeout = connect_timeout;
2294 }
2295 
2296 static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
2297 		unsigned long connect_timeout,
2298 		unsigned long reconnect_timeout)
2299 {
2300 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2301 
2302 	spin_lock(&xprt->transport_lock);
2303 	if (reconnect_timeout < xprt->max_reconnect_timeout)
2304 		xprt->max_reconnect_timeout = reconnect_timeout;
2305 	if (connect_timeout < xprt->connect_timeout)
2306 		xs_tcp_do_set_connect_timeout(xprt, connect_timeout);
2307 	set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2308 	spin_unlock(&xprt->transport_lock);
2309 }
2310 
2311 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2312 {
2313 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2314 
2315 	if (!transport->inet) {
2316 		struct sock *sk = sock->sk;
2317 
2318 		/* Avoid temporary address, they are bad for long-lived
2319 		 * connections such as NFS mounts.
2320 		 * RFC4941, section 3.6 suggests that:
2321 		 *    Individual applications, which have specific
2322 		 *    knowledge about the normal duration of connections,
2323 		 *    MAY override this as appropriate.
2324 		 */
2325 		if (xs_addr(xprt)->sa_family == PF_INET6) {
2326 			ip6_sock_set_addr_preferences(sk,
2327 				IPV6_PREFER_SRC_PUBLIC);
2328 		}
2329 
2330 		xs_tcp_set_socket_timeouts(xprt, sock);
2331 		tcp_sock_set_nodelay(sk);
2332 
2333 		lock_sock(sk);
2334 
2335 		xs_save_old_callbacks(transport, sk);
2336 
2337 		sk->sk_user_data = xprt;
2338 		sk->sk_data_ready = xs_data_ready;
2339 		sk->sk_state_change = xs_tcp_state_change;
2340 		sk->sk_write_space = xs_tcp_write_space;
2341 		sk->sk_error_report = xs_error_report;
2342 		sk->sk_use_task_frag = false;
2343 
2344 		/* socket options */
2345 		sock_reset_flag(sk, SOCK_LINGER);
2346 
2347 		xprt_clear_connected(xprt);
2348 
2349 		/* Reset to new socket */
2350 		transport->sock = sock;
2351 		transport->inet = sk;
2352 
2353 		release_sock(sk);
2354 	}
2355 
2356 	if (!xprt_bound(xprt))
2357 		return -ENOTCONN;
2358 
2359 	xs_set_memalloc(xprt);
2360 
2361 	xs_stream_start_connect(transport);
2362 
2363 	/* Tell the socket layer to start connecting... */
2364 	set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2365 	return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2366 }
2367 
2368 /**
2369  * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2370  * @work: queued work item
2371  *
2372  * Invoked by a work queue tasklet.
2373  */
2374 static void xs_tcp_setup_socket(struct work_struct *work)
2375 {
2376 	struct sock_xprt *transport =
2377 		container_of(work, struct sock_xprt, connect_worker.work);
2378 	struct socket *sock = transport->sock;
2379 	struct rpc_xprt *xprt = &transport->xprt;
2380 	int status;
2381 	unsigned int pflags = current->flags;
2382 
2383 	if (atomic_read(&xprt->swapper))
2384 		current->flags |= PF_MEMALLOC;
2385 
2386 	if (xprt_connected(xprt))
2387 		goto out;
2388 	if (test_and_clear_bit(XPRT_SOCK_CONNECT_SENT,
2389 			       &transport->sock_state) ||
2390 	    !sock) {
2391 		xs_reset_transport(transport);
2392 		sock = xs_create_sock(xprt, transport, xs_addr(xprt)->sa_family,
2393 				      SOCK_STREAM, IPPROTO_TCP, true);
2394 		if (IS_ERR(sock)) {
2395 			xprt_wake_pending_tasks(xprt, PTR_ERR(sock));
2396 			goto out;
2397 		}
2398 	}
2399 
2400 	dprintk("RPC:       worker connecting xprt %p via %s to "
2401 				"%s (port %s)\n", xprt,
2402 			xprt->address_strings[RPC_DISPLAY_PROTO],
2403 			xprt->address_strings[RPC_DISPLAY_ADDR],
2404 			xprt->address_strings[RPC_DISPLAY_PORT]);
2405 
2406 	status = xs_tcp_finish_connecting(xprt, sock);
2407 	trace_rpc_socket_connect(xprt, sock, status);
2408 	dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2409 			xprt, -status, xprt_connected(xprt),
2410 			sock->sk->sk_state);
2411 	switch (status) {
2412 	case 0:
2413 	case -EINPROGRESS:
2414 		/* SYN_SENT! */
2415 		set_bit(XPRT_SOCK_CONNECT_SENT, &transport->sock_state);
2416 		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2417 			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2418 		fallthrough;
2419 	case -EALREADY:
2420 		goto out_unlock;
2421 	case -EADDRNOTAVAIL:
2422 		/* Source port number is unavailable. Try a new one! */
2423 		transport->srcport = 0;
2424 		status = -EAGAIN;
2425 		break;
2426 	case -EINVAL:
2427 		/* Happens, for instance, if the user specified a link
2428 		 * local IPv6 address without a scope-id.
2429 		 */
2430 	case -ECONNREFUSED:
2431 	case -ECONNRESET:
2432 	case -ENETDOWN:
2433 	case -ENETUNREACH:
2434 	case -EHOSTUNREACH:
2435 	case -EADDRINUSE:
2436 	case -ENOBUFS:
2437 		break;
2438 	default:
2439 		printk("%s: connect returned unhandled error %d\n",
2440 			__func__, status);
2441 		status = -EAGAIN;
2442 	}
2443 
2444 	/* xs_tcp_force_close() wakes tasks with a fixed error code.
2445 	 * We need to wake them first to ensure the correct error code.
2446 	 */
2447 	xprt_wake_pending_tasks(xprt, status);
2448 	xs_tcp_force_close(xprt);
2449 out:
2450 	xprt_clear_connecting(xprt);
2451 out_unlock:
2452 	xprt_unlock_connect(xprt, transport);
2453 	current_restore_flags(pflags, PF_MEMALLOC);
2454 }
2455 
2456 /*
2457  * Transfer the connected socket to @upper_transport, then mark that
2458  * xprt CONNECTED.
2459  */
2460 static int xs_tcp_tls_finish_connecting(struct rpc_xprt *lower_xprt,
2461 					struct sock_xprt *upper_transport)
2462 {
2463 	struct sock_xprt *lower_transport =
2464 			container_of(lower_xprt, struct sock_xprt, xprt);
2465 	struct rpc_xprt *upper_xprt = &upper_transport->xprt;
2466 
2467 	if (!upper_transport->inet) {
2468 		struct socket *sock = lower_transport->sock;
2469 		struct sock *sk = sock->sk;
2470 
2471 		/* Avoid temporary address, they are bad for long-lived
2472 		 * connections such as NFS mounts.
2473 		 * RFC4941, section 3.6 suggests that:
2474 		 *    Individual applications, which have specific
2475 		 *    knowledge about the normal duration of connections,
2476 		 *    MAY override this as appropriate.
2477 		 */
2478 		if (xs_addr(upper_xprt)->sa_family == PF_INET6)
2479 			ip6_sock_set_addr_preferences(sk, IPV6_PREFER_SRC_PUBLIC);
2480 
2481 		xs_tcp_set_socket_timeouts(upper_xprt, sock);
2482 		tcp_sock_set_nodelay(sk);
2483 
2484 		lock_sock(sk);
2485 
2486 		/* @sk is already connected, so it now has the RPC callbacks.
2487 		 * Reach into @lower_transport to save the original ones.
2488 		 */
2489 		upper_transport->old_data_ready = lower_transport->old_data_ready;
2490 		upper_transport->old_state_change = lower_transport->old_state_change;
2491 		upper_transport->old_write_space = lower_transport->old_write_space;
2492 		upper_transport->old_error_report = lower_transport->old_error_report;
2493 		sk->sk_user_data = upper_xprt;
2494 
2495 		/* socket options */
2496 		sock_reset_flag(sk, SOCK_LINGER);
2497 
2498 		xprt_clear_connected(upper_xprt);
2499 
2500 		upper_transport->sock = sock;
2501 		upper_transport->inet = sk;
2502 		upper_transport->file = lower_transport->file;
2503 
2504 		release_sock(sk);
2505 
2506 		/* Reset lower_transport before shutting down its clnt */
2507 		mutex_lock(&lower_transport->recv_mutex);
2508 		lower_transport->inet = NULL;
2509 		lower_transport->sock = NULL;
2510 		lower_transport->file = NULL;
2511 
2512 		xprt_clear_connected(lower_xprt);
2513 		xs_sock_reset_connection_flags(lower_xprt);
2514 		xs_stream_reset_connect(lower_transport);
2515 		mutex_unlock(&lower_transport->recv_mutex);
2516 	}
2517 
2518 	if (!xprt_bound(upper_xprt))
2519 		return -ENOTCONN;
2520 
2521 	xs_set_memalloc(upper_xprt);
2522 
2523 	if (!xprt_test_and_set_connected(upper_xprt)) {
2524 		upper_xprt->connect_cookie++;
2525 		clear_bit(XPRT_SOCK_CONNECTING, &upper_transport->sock_state);
2526 		xprt_clear_connecting(upper_xprt);
2527 
2528 		upper_xprt->stat.connect_count++;
2529 		upper_xprt->stat.connect_time += (long)jiffies -
2530 					   upper_xprt->stat.connect_start;
2531 		xs_run_error_worker(upper_transport, XPRT_SOCK_WAKE_PENDING);
2532 	}
2533 	return 0;
2534 }
2535 
2536 /**
2537  * xs_tls_handshake_done - TLS handshake completion handler
2538  * @data: address of xprt to wake
2539  * @status: status of handshake
2540  * @peerid: serial number of key containing the remote's identity
2541  *
2542  */
2543 static void xs_tls_handshake_done(void *data, int status, key_serial_t peerid)
2544 {
2545 	struct rpc_xprt *lower_xprt = data;
2546 	struct sock_xprt *lower_transport =
2547 				container_of(lower_xprt, struct sock_xprt, xprt);
2548 
2549 	lower_transport->xprt_err = status ? -EACCES : 0;
2550 	complete(&lower_transport->handshake_done);
2551 	xprt_put(lower_xprt);
2552 }
2553 
2554 static int xs_tls_handshake_sync(struct rpc_xprt *lower_xprt, struct xprtsec_parms *xprtsec)
2555 {
2556 	struct sock_xprt *lower_transport =
2557 				container_of(lower_xprt, struct sock_xprt, xprt);
2558 	struct tls_handshake_args args = {
2559 		.ta_sock	= lower_transport->sock,
2560 		.ta_done	= xs_tls_handshake_done,
2561 		.ta_data	= xprt_get(lower_xprt),
2562 		.ta_peername	= lower_xprt->servername,
2563 	};
2564 	struct sock *sk = lower_transport->inet;
2565 	int rc;
2566 
2567 	init_completion(&lower_transport->handshake_done);
2568 	set_bit(XPRT_SOCK_IGNORE_RECV, &lower_transport->sock_state);
2569 	lower_transport->xprt_err = -ETIMEDOUT;
2570 	switch (xprtsec->policy) {
2571 	case RPC_XPRTSEC_TLS_ANON:
2572 		rc = tls_client_hello_anon(&args, GFP_KERNEL);
2573 		if (rc)
2574 			goto out_put_xprt;
2575 		break;
2576 	case RPC_XPRTSEC_TLS_X509:
2577 		args.ta_my_cert = xprtsec->cert_serial;
2578 		args.ta_my_privkey = xprtsec->privkey_serial;
2579 		rc = tls_client_hello_x509(&args, GFP_KERNEL);
2580 		if (rc)
2581 			goto out_put_xprt;
2582 		break;
2583 	default:
2584 		rc = -EACCES;
2585 		goto out_put_xprt;
2586 	}
2587 
2588 	rc = wait_for_completion_interruptible_timeout(&lower_transport->handshake_done,
2589 						       XS_TLS_HANDSHAKE_TO);
2590 	if (rc <= 0) {
2591 		if (!tls_handshake_cancel(sk)) {
2592 			if (rc == 0)
2593 				rc = -ETIMEDOUT;
2594 			goto out_put_xprt;
2595 		}
2596 	}
2597 
2598 	rc = lower_transport->xprt_err;
2599 
2600 out:
2601 	xs_stream_reset_connect(lower_transport);
2602 	clear_bit(XPRT_SOCK_IGNORE_RECV, &lower_transport->sock_state);
2603 	return rc;
2604 
2605 out_put_xprt:
2606 	xprt_put(lower_xprt);
2607 	goto out;
2608 }
2609 
2610 /**
2611  * xs_tcp_tls_setup_socket - establish a TLS session on a TCP socket
2612  * @work: queued work item
2613  *
2614  * Invoked by a work queue tasklet.
2615  *
2616  * For RPC-with-TLS, there is a two-stage connection process.
2617  *
2618  * The "upper-layer xprt" is visible to the RPC consumer. Once it has
2619  * been marked connected, the consumer knows that a TCP connection and
2620  * a TLS session have been established.
2621  *
2622  * A "lower-layer xprt", created in this function, handles the mechanics
2623  * of connecting the TCP socket, performing the RPC_AUTH_TLS probe, and
2624  * then driving the TLS handshake. Once all that is complete, the upper
2625  * layer xprt is marked connected.
2626  */
2627 static void xs_tcp_tls_setup_socket(struct work_struct *work)
2628 {
2629 	struct sock_xprt *upper_transport =
2630 		container_of(work, struct sock_xprt, connect_worker.work);
2631 	struct rpc_clnt *upper_clnt = upper_transport->clnt;
2632 	struct rpc_xprt *upper_xprt = &upper_transport->xprt;
2633 	struct rpc_create_args args = {
2634 		.net		= upper_xprt->xprt_net,
2635 		.protocol	= upper_xprt->prot,
2636 		.address	= (struct sockaddr *)&upper_xprt->addr,
2637 		.addrsize	= upper_xprt->addrlen,
2638 		.timeout	= upper_clnt->cl_timeout,
2639 		.servername	= upper_xprt->servername,
2640 		.program	= upper_clnt->cl_program,
2641 		.prognumber	= upper_clnt->cl_prog,
2642 		.version	= upper_clnt->cl_vers,
2643 		.authflavor	= RPC_AUTH_TLS,
2644 		.cred		= upper_clnt->cl_cred,
2645 		.xprtsec	= {
2646 			.policy		= RPC_XPRTSEC_NONE,
2647 		},
2648 	};
2649 	unsigned int pflags = current->flags;
2650 	struct rpc_clnt *lower_clnt;
2651 	struct rpc_xprt *lower_xprt;
2652 	int status;
2653 
2654 	if (atomic_read(&upper_xprt->swapper))
2655 		current->flags |= PF_MEMALLOC;
2656 
2657 	xs_stream_start_connect(upper_transport);
2658 
2659 	/* This implicitly sends an RPC_AUTH_TLS probe */
2660 	lower_clnt = rpc_create(&args);
2661 	if (IS_ERR(lower_clnt)) {
2662 		trace_rpc_tls_unavailable(upper_clnt, upper_xprt);
2663 		clear_bit(XPRT_SOCK_CONNECTING, &upper_transport->sock_state);
2664 		xprt_clear_connecting(upper_xprt);
2665 		xprt_wake_pending_tasks(upper_xprt, PTR_ERR(lower_clnt));
2666 		xs_run_error_worker(upper_transport, XPRT_SOCK_WAKE_PENDING);
2667 		goto out_unlock;
2668 	}
2669 
2670 	/* RPC_AUTH_TLS probe was successful. Try a TLS handshake on
2671 	 * the lower xprt.
2672 	 */
2673 	rcu_read_lock();
2674 	lower_xprt = rcu_dereference(lower_clnt->cl_xprt);
2675 	rcu_read_unlock();
2676 
2677 	if (wait_on_bit_lock(&lower_xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2678 		goto out_unlock;
2679 
2680 	status = xs_tls_handshake_sync(lower_xprt, &upper_xprt->xprtsec);
2681 	if (status) {
2682 		trace_rpc_tls_not_started(upper_clnt, upper_xprt);
2683 		goto out_close;
2684 	}
2685 
2686 	status = xs_tcp_tls_finish_connecting(lower_xprt, upper_transport);
2687 	if (status)
2688 		goto out_close;
2689 	xprt_release_write(lower_xprt, NULL);
2690 
2691 	trace_rpc_socket_connect(upper_xprt, upper_transport->sock, 0);
2692 	if (!xprt_test_and_set_connected(upper_xprt)) {
2693 		upper_xprt->connect_cookie++;
2694 		clear_bit(XPRT_SOCK_CONNECTING, &upper_transport->sock_state);
2695 		xprt_clear_connecting(upper_xprt);
2696 
2697 		upper_xprt->stat.connect_count++;
2698 		upper_xprt->stat.connect_time += (long)jiffies -
2699 					   upper_xprt->stat.connect_start;
2700 		xs_run_error_worker(upper_transport, XPRT_SOCK_WAKE_PENDING);
2701 	}
2702 	rpc_shutdown_client(lower_clnt);
2703 
2704 out_unlock:
2705 	current_restore_flags(pflags, PF_MEMALLOC);
2706 	upper_transport->clnt = NULL;
2707 	xprt_unlock_connect(upper_xprt, upper_transport);
2708 	return;
2709 
2710 out_close:
2711 	xprt_release_write(lower_xprt, NULL);
2712 	rpc_shutdown_client(lower_clnt);
2713 
2714 	/* xprt_force_disconnect() wakes tasks with a fixed tk_status code.
2715 	 * Wake them first here to ensure they get our tk_status code.
2716 	 */
2717 	xprt_wake_pending_tasks(upper_xprt, status);
2718 	xs_tcp_force_close(upper_xprt);
2719 	xprt_clear_connecting(upper_xprt);
2720 	goto out_unlock;
2721 }
2722 
2723 /**
2724  * xs_connect - connect a socket to a remote endpoint
2725  * @xprt: pointer to transport structure
2726  * @task: address of RPC task that manages state of connect request
2727  *
2728  * TCP: If the remote end dropped the connection, delay reconnecting.
2729  *
2730  * UDP socket connects are synchronous, but we use a work queue anyway
2731  * to guarantee that even unprivileged user processes can set up a
2732  * socket on a privileged port.
2733  *
2734  * If a UDP socket connect fails, the delay behavior here prevents
2735  * retry floods (hard mounts).
2736  */
2737 static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2738 {
2739 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2740 	unsigned long delay = 0;
2741 
2742 	WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2743 
2744 	if (transport->sock != NULL) {
2745 		dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2746 			"seconds\n", xprt, xprt->reestablish_timeout / HZ);
2747 
2748 		delay = xprt_reconnect_delay(xprt);
2749 		xprt_reconnect_backoff(xprt, XS_TCP_INIT_REEST_TO);
2750 
2751 	} else
2752 		dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2753 
2754 	transport->clnt = task->tk_client;
2755 	queue_delayed_work(xprtiod_workqueue,
2756 			&transport->connect_worker,
2757 			delay);
2758 }
2759 
2760 static void xs_wake_disconnect(struct sock_xprt *transport)
2761 {
2762 	if (test_and_clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state))
2763 		xs_tcp_force_close(&transport->xprt);
2764 }
2765 
2766 static void xs_wake_write(struct sock_xprt *transport)
2767 {
2768 	if (test_and_clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state))
2769 		xprt_write_space(&transport->xprt);
2770 }
2771 
2772 static void xs_wake_error(struct sock_xprt *transport)
2773 {
2774 	int sockerr;
2775 
2776 	if (!test_and_clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2777 		return;
2778 	sockerr = xchg(&transport->xprt_err, 0);
2779 	if (sockerr < 0) {
2780 		xprt_wake_pending_tasks(&transport->xprt, sockerr);
2781 		xs_tcp_force_close(&transport->xprt);
2782 	}
2783 }
2784 
2785 static void xs_wake_pending(struct sock_xprt *transport)
2786 {
2787 	if (test_and_clear_bit(XPRT_SOCK_WAKE_PENDING, &transport->sock_state))
2788 		xprt_wake_pending_tasks(&transport->xprt, -EAGAIN);
2789 }
2790 
2791 static void xs_error_handle(struct work_struct *work)
2792 {
2793 	struct sock_xprt *transport = container_of(work,
2794 			struct sock_xprt, error_worker);
2795 
2796 	xs_wake_disconnect(transport);
2797 	xs_wake_write(transport);
2798 	xs_wake_error(transport);
2799 	xs_wake_pending(transport);
2800 }
2801 
2802 /**
2803  * xs_local_print_stats - display AF_LOCAL socket-specific stats
2804  * @xprt: rpc_xprt struct containing statistics
2805  * @seq: output file
2806  *
2807  */
2808 static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2809 {
2810 	long idle_time = 0;
2811 
2812 	if (xprt_connected(xprt))
2813 		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2814 
2815 	seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2816 			"%llu %llu %lu %llu %llu\n",
2817 			xprt->stat.bind_count,
2818 			xprt->stat.connect_count,
2819 			xprt->stat.connect_time / HZ,
2820 			idle_time,
2821 			xprt->stat.sends,
2822 			xprt->stat.recvs,
2823 			xprt->stat.bad_xids,
2824 			xprt->stat.req_u,
2825 			xprt->stat.bklog_u,
2826 			xprt->stat.max_slots,
2827 			xprt->stat.sending_u,
2828 			xprt->stat.pending_u);
2829 }
2830 
2831 /**
2832  * xs_udp_print_stats - display UDP socket-specific stats
2833  * @xprt: rpc_xprt struct containing statistics
2834  * @seq: output file
2835  *
2836  */
2837 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2838 {
2839 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2840 
2841 	seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2842 			"%lu %llu %llu\n",
2843 			transport->srcport,
2844 			xprt->stat.bind_count,
2845 			xprt->stat.sends,
2846 			xprt->stat.recvs,
2847 			xprt->stat.bad_xids,
2848 			xprt->stat.req_u,
2849 			xprt->stat.bklog_u,
2850 			xprt->stat.max_slots,
2851 			xprt->stat.sending_u,
2852 			xprt->stat.pending_u);
2853 }
2854 
2855 /**
2856  * xs_tcp_print_stats - display TCP socket-specific stats
2857  * @xprt: rpc_xprt struct containing statistics
2858  * @seq: output file
2859  *
2860  */
2861 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2862 {
2863 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2864 	long idle_time = 0;
2865 
2866 	if (xprt_connected(xprt))
2867 		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2868 
2869 	seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2870 			"%llu %llu %lu %llu %llu\n",
2871 			transport->srcport,
2872 			xprt->stat.bind_count,
2873 			xprt->stat.connect_count,
2874 			xprt->stat.connect_time / HZ,
2875 			idle_time,
2876 			xprt->stat.sends,
2877 			xprt->stat.recvs,
2878 			xprt->stat.bad_xids,
2879 			xprt->stat.req_u,
2880 			xprt->stat.bklog_u,
2881 			xprt->stat.max_slots,
2882 			xprt->stat.sending_u,
2883 			xprt->stat.pending_u);
2884 }
2885 
2886 /*
2887  * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2888  * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2889  * to use the server side send routines.
2890  */
2891 static int bc_malloc(struct rpc_task *task)
2892 {
2893 	struct rpc_rqst *rqst = task->tk_rqstp;
2894 	size_t size = rqst->rq_callsize;
2895 	struct page *page;
2896 	struct rpc_buffer *buf;
2897 
2898 	if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2899 		WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2900 			  size);
2901 		return -EINVAL;
2902 	}
2903 
2904 	page = alloc_page(GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
2905 	if (!page)
2906 		return -ENOMEM;
2907 
2908 	buf = page_address(page);
2909 	buf->len = PAGE_SIZE;
2910 
2911 	rqst->rq_buffer = buf->data;
2912 	rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2913 	return 0;
2914 }
2915 
2916 /*
2917  * Free the space allocated in the bc_alloc routine
2918  */
2919 static void bc_free(struct rpc_task *task)
2920 {
2921 	void *buffer = task->tk_rqstp->rq_buffer;
2922 	struct rpc_buffer *buf;
2923 
2924 	buf = container_of(buffer, struct rpc_buffer, data);
2925 	free_page((unsigned long)buf);
2926 }
2927 
2928 static int bc_sendto(struct rpc_rqst *req)
2929 {
2930 	struct xdr_buf *xdr = &req->rq_snd_buf;
2931 	struct sock_xprt *transport =
2932 			container_of(req->rq_xprt, struct sock_xprt, xprt);
2933 	struct msghdr msg = {
2934 		.msg_flags	= 0,
2935 	};
2936 	rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT |
2937 					 (u32)xdr->len);
2938 	unsigned int sent = 0;
2939 	int err;
2940 
2941 	req->rq_xtime = ktime_get();
2942 	err = xdr_alloc_bvec(xdr, rpc_task_gfp_mask());
2943 	if (err < 0)
2944 		return err;
2945 	err = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, marker, &sent);
2946 	xdr_free_bvec(xdr);
2947 	if (err < 0 || sent != (xdr->len + sizeof(marker)))
2948 		return -EAGAIN;
2949 	return sent;
2950 }
2951 
2952 /**
2953  * bc_send_request - Send a backchannel Call on a TCP socket
2954  * @req: rpc_rqst containing Call message to be sent
2955  *
2956  * xpt_mutex ensures @rqstp's whole message is written to the socket
2957  * without interruption.
2958  *
2959  * Return values:
2960  *   %0 if the message was sent successfully
2961  *   %ENOTCONN if the message was not sent
2962  */
2963 static int bc_send_request(struct rpc_rqst *req)
2964 {
2965 	struct svc_xprt	*xprt;
2966 	int len;
2967 
2968 	/*
2969 	 * Get the server socket associated with this callback xprt
2970 	 */
2971 	xprt = req->rq_xprt->bc_xprt;
2972 
2973 	/*
2974 	 * Grab the mutex to serialize data as the connection is shared
2975 	 * with the fore channel
2976 	 */
2977 	mutex_lock(&xprt->xpt_mutex);
2978 	if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2979 		len = -ENOTCONN;
2980 	else
2981 		len = bc_sendto(req);
2982 	mutex_unlock(&xprt->xpt_mutex);
2983 
2984 	if (len > 0)
2985 		len = 0;
2986 
2987 	return len;
2988 }
2989 
2990 /*
2991  * The close routine. Since this is client initiated, we do nothing
2992  */
2993 
2994 static void bc_close(struct rpc_xprt *xprt)
2995 {
2996 	xprt_disconnect_done(xprt);
2997 }
2998 
2999 /*
3000  * The xprt destroy routine. Again, because this connection is client
3001  * initiated, we do nothing
3002  */
3003 
3004 static void bc_destroy(struct rpc_xprt *xprt)
3005 {
3006 	dprintk("RPC:       bc_destroy xprt %p\n", xprt);
3007 
3008 	xs_xprt_free(xprt);
3009 	module_put(THIS_MODULE);
3010 }
3011 
3012 static const struct rpc_xprt_ops xs_local_ops = {
3013 	.reserve_xprt		= xprt_reserve_xprt,
3014 	.release_xprt		= xprt_release_xprt,
3015 	.alloc_slot		= xprt_alloc_slot,
3016 	.free_slot		= xprt_free_slot,
3017 	.rpcbind		= xs_local_rpcbind,
3018 	.set_port		= xs_local_set_port,
3019 	.connect		= xs_local_connect,
3020 	.buf_alloc		= rpc_malloc,
3021 	.buf_free		= rpc_free,
3022 	.prepare_request	= xs_stream_prepare_request,
3023 	.send_request		= xs_local_send_request,
3024 	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
3025 	.close			= xs_close,
3026 	.destroy		= xs_destroy,
3027 	.print_stats		= xs_local_print_stats,
3028 	.enable_swap		= xs_enable_swap,
3029 	.disable_swap		= xs_disable_swap,
3030 };
3031 
3032 static const struct rpc_xprt_ops xs_udp_ops = {
3033 	.set_buffer_size	= xs_udp_set_buffer_size,
3034 	.reserve_xprt		= xprt_reserve_xprt_cong,
3035 	.release_xprt		= xprt_release_xprt_cong,
3036 	.alloc_slot		= xprt_alloc_slot,
3037 	.free_slot		= xprt_free_slot,
3038 	.rpcbind		= rpcb_getport_async,
3039 	.set_port		= xs_set_port,
3040 	.connect		= xs_connect,
3041 	.get_srcaddr		= xs_sock_srcaddr,
3042 	.get_srcport		= xs_sock_srcport,
3043 	.buf_alloc		= rpc_malloc,
3044 	.buf_free		= rpc_free,
3045 	.send_request		= xs_udp_send_request,
3046 	.wait_for_reply_request	= xprt_wait_for_reply_request_rtt,
3047 	.timer			= xs_udp_timer,
3048 	.release_request	= xprt_release_rqst_cong,
3049 	.close			= xs_close,
3050 	.destroy		= xs_destroy,
3051 	.print_stats		= xs_udp_print_stats,
3052 	.enable_swap		= xs_enable_swap,
3053 	.disable_swap		= xs_disable_swap,
3054 	.inject_disconnect	= xs_inject_disconnect,
3055 };
3056 
3057 static const struct rpc_xprt_ops xs_tcp_ops = {
3058 	.reserve_xprt		= xprt_reserve_xprt,
3059 	.release_xprt		= xprt_release_xprt,
3060 	.alloc_slot		= xprt_alloc_slot,
3061 	.free_slot		= xprt_free_slot,
3062 	.rpcbind		= rpcb_getport_async,
3063 	.set_port		= xs_set_port,
3064 	.connect		= xs_connect,
3065 	.get_srcaddr		= xs_sock_srcaddr,
3066 	.get_srcport		= xs_sock_srcport,
3067 	.buf_alloc		= rpc_malloc,
3068 	.buf_free		= rpc_free,
3069 	.prepare_request	= xs_stream_prepare_request,
3070 	.send_request		= xs_tcp_send_request,
3071 	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
3072 	.close			= xs_tcp_shutdown,
3073 	.destroy		= xs_destroy,
3074 	.set_connect_timeout	= xs_tcp_set_connect_timeout,
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 #ifdef CONFIG_SUNRPC_BACKCHANNEL
3080 	.bc_setup		= xprt_setup_bc,
3081 	.bc_maxpayload		= xs_tcp_bc_maxpayload,
3082 	.bc_num_slots		= xprt_bc_max_slots,
3083 	.bc_free_rqst		= xprt_free_bc_rqst,
3084 	.bc_destroy		= xprt_destroy_bc,
3085 #endif
3086 };
3087 
3088 /*
3089  * The rpc_xprt_ops for the server backchannel
3090  */
3091 
3092 static const struct rpc_xprt_ops bc_tcp_ops = {
3093 	.reserve_xprt		= xprt_reserve_xprt,
3094 	.release_xprt		= xprt_release_xprt,
3095 	.alloc_slot		= xprt_alloc_slot,
3096 	.free_slot		= xprt_free_slot,
3097 	.buf_alloc		= bc_malloc,
3098 	.buf_free		= bc_free,
3099 	.send_request		= bc_send_request,
3100 	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
3101 	.close			= bc_close,
3102 	.destroy		= bc_destroy,
3103 	.print_stats		= xs_tcp_print_stats,
3104 	.enable_swap		= xs_enable_swap,
3105 	.disable_swap		= xs_disable_swap,
3106 	.inject_disconnect	= xs_inject_disconnect,
3107 };
3108 
3109 static int xs_init_anyaddr(const int family, struct sockaddr *sap)
3110 {
3111 	static const struct sockaddr_in sin = {
3112 		.sin_family		= AF_INET,
3113 		.sin_addr.s_addr	= htonl(INADDR_ANY),
3114 	};
3115 	static const struct sockaddr_in6 sin6 = {
3116 		.sin6_family		= AF_INET6,
3117 		.sin6_addr		= IN6ADDR_ANY_INIT,
3118 	};
3119 
3120 	switch (family) {
3121 	case AF_LOCAL:
3122 		break;
3123 	case AF_INET:
3124 		memcpy(sap, &sin, sizeof(sin));
3125 		break;
3126 	case AF_INET6:
3127 		memcpy(sap, &sin6, sizeof(sin6));
3128 		break;
3129 	default:
3130 		dprintk("RPC:       %s: Bad address family\n", __func__);
3131 		return -EAFNOSUPPORT;
3132 	}
3133 	return 0;
3134 }
3135 
3136 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
3137 				      unsigned int slot_table_size,
3138 				      unsigned int max_slot_table_size)
3139 {
3140 	struct rpc_xprt *xprt;
3141 	struct sock_xprt *new;
3142 
3143 	if (args->addrlen > sizeof(xprt->addr)) {
3144 		dprintk("RPC:       xs_setup_xprt: address too large\n");
3145 		return ERR_PTR(-EBADF);
3146 	}
3147 
3148 	xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
3149 			max_slot_table_size);
3150 	if (xprt == NULL) {
3151 		dprintk("RPC:       xs_setup_xprt: couldn't allocate "
3152 				"rpc_xprt\n");
3153 		return ERR_PTR(-ENOMEM);
3154 	}
3155 
3156 	new = container_of(xprt, struct sock_xprt, xprt);
3157 	mutex_init(&new->recv_mutex);
3158 	memcpy(&xprt->addr, args->dstaddr, args->addrlen);
3159 	xprt->addrlen = args->addrlen;
3160 	if (args->srcaddr)
3161 		memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
3162 	else {
3163 		int err;
3164 		err = xs_init_anyaddr(args->dstaddr->sa_family,
3165 					(struct sockaddr *)&new->srcaddr);
3166 		if (err != 0) {
3167 			xprt_free(xprt);
3168 			return ERR_PTR(err);
3169 		}
3170 	}
3171 
3172 	return xprt;
3173 }
3174 
3175 static const struct rpc_timeout xs_local_default_timeout = {
3176 	.to_initval = 10 * HZ,
3177 	.to_maxval = 10 * HZ,
3178 	.to_retries = 2,
3179 };
3180 
3181 /**
3182  * xs_setup_local - Set up transport to use an AF_LOCAL socket
3183  * @args: rpc transport creation arguments
3184  *
3185  * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
3186  */
3187 static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
3188 {
3189 	struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
3190 	struct sock_xprt *transport;
3191 	struct rpc_xprt *xprt;
3192 	struct rpc_xprt *ret;
3193 
3194 	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3195 			xprt_max_tcp_slot_table_entries);
3196 	if (IS_ERR(xprt))
3197 		return xprt;
3198 	transport = container_of(xprt, struct sock_xprt, xprt);
3199 
3200 	xprt->prot = 0;
3201 	xprt->xprt_class = &xs_local_transport;
3202 	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3203 
3204 	xprt->bind_timeout = XS_BIND_TO;
3205 	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
3206 	xprt->idle_timeout = XS_IDLE_DISC_TO;
3207 
3208 	xprt->ops = &xs_local_ops;
3209 	xprt->timeout = &xs_local_default_timeout;
3210 
3211 	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
3212 	INIT_WORK(&transport->error_worker, xs_error_handle);
3213 	INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket);
3214 
3215 	switch (sun->sun_family) {
3216 	case AF_LOCAL:
3217 		if (sun->sun_path[0] != '/' && sun->sun_path[0] != '\0') {
3218 			dprintk("RPC:       bad AF_LOCAL address: %s\n",
3219 					sun->sun_path);
3220 			ret = ERR_PTR(-EINVAL);
3221 			goto out_err;
3222 		}
3223 		xprt_set_bound(xprt);
3224 		xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
3225 		break;
3226 	default:
3227 		ret = ERR_PTR(-EAFNOSUPPORT);
3228 		goto out_err;
3229 	}
3230 
3231 	dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
3232 			xprt->address_strings[RPC_DISPLAY_ADDR]);
3233 
3234 	if (try_module_get(THIS_MODULE))
3235 		return xprt;
3236 	ret = ERR_PTR(-EINVAL);
3237 out_err:
3238 	xs_xprt_free(xprt);
3239 	return ret;
3240 }
3241 
3242 static const struct rpc_timeout xs_udp_default_timeout = {
3243 	.to_initval = 5 * HZ,
3244 	.to_maxval = 30 * HZ,
3245 	.to_increment = 5 * HZ,
3246 	.to_retries = 5,
3247 };
3248 
3249 /**
3250  * xs_setup_udp - Set up transport to use a UDP socket
3251  * @args: rpc transport creation arguments
3252  *
3253  */
3254 static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
3255 {
3256 	struct sockaddr *addr = args->dstaddr;
3257 	struct rpc_xprt *xprt;
3258 	struct sock_xprt *transport;
3259 	struct rpc_xprt *ret;
3260 
3261 	xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
3262 			xprt_udp_slot_table_entries);
3263 	if (IS_ERR(xprt))
3264 		return xprt;
3265 	transport = container_of(xprt, struct sock_xprt, xprt);
3266 
3267 	xprt->prot = IPPROTO_UDP;
3268 	xprt->xprt_class = &xs_udp_transport;
3269 	/* XXX: header size can vary due to auth type, IPv6, etc. */
3270 	xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
3271 
3272 	xprt->bind_timeout = XS_BIND_TO;
3273 	xprt->reestablish_timeout = XS_UDP_REEST_TO;
3274 	xprt->idle_timeout = XS_IDLE_DISC_TO;
3275 
3276 	xprt->ops = &xs_udp_ops;
3277 
3278 	xprt->timeout = &xs_udp_default_timeout;
3279 
3280 	INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
3281 	INIT_WORK(&transport->error_worker, xs_error_handle);
3282 	INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
3283 
3284 	switch (addr->sa_family) {
3285 	case AF_INET:
3286 		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3287 			xprt_set_bound(xprt);
3288 
3289 		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
3290 		break;
3291 	case AF_INET6:
3292 		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3293 			xprt_set_bound(xprt);
3294 
3295 		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
3296 		break;
3297 	default:
3298 		ret = ERR_PTR(-EAFNOSUPPORT);
3299 		goto out_err;
3300 	}
3301 
3302 	if (xprt_bound(xprt))
3303 		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3304 				xprt->address_strings[RPC_DISPLAY_ADDR],
3305 				xprt->address_strings[RPC_DISPLAY_PORT],
3306 				xprt->address_strings[RPC_DISPLAY_PROTO]);
3307 	else
3308 		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3309 				xprt->address_strings[RPC_DISPLAY_ADDR],
3310 				xprt->address_strings[RPC_DISPLAY_PROTO]);
3311 
3312 	if (try_module_get(THIS_MODULE))
3313 		return xprt;
3314 	ret = ERR_PTR(-EINVAL);
3315 out_err:
3316 	xs_xprt_free(xprt);
3317 	return ret;
3318 }
3319 
3320 static const struct rpc_timeout xs_tcp_default_timeout = {
3321 	.to_initval = 60 * HZ,
3322 	.to_maxval = 60 * HZ,
3323 	.to_retries = 2,
3324 };
3325 
3326 /**
3327  * xs_setup_tcp - Set up transport to use a TCP socket
3328  * @args: rpc transport creation arguments
3329  *
3330  */
3331 static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
3332 {
3333 	struct sockaddr *addr = args->dstaddr;
3334 	struct rpc_xprt *xprt;
3335 	struct sock_xprt *transport;
3336 	struct rpc_xprt *ret;
3337 	unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
3338 
3339 	if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
3340 		max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
3341 
3342 	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3343 			max_slot_table_size);
3344 	if (IS_ERR(xprt))
3345 		return xprt;
3346 	transport = container_of(xprt, struct sock_xprt, xprt);
3347 
3348 	xprt->prot = IPPROTO_TCP;
3349 	xprt->xprt_class = &xs_tcp_transport;
3350 	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3351 
3352 	xprt->bind_timeout = XS_BIND_TO;
3353 	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
3354 	xprt->idle_timeout = XS_IDLE_DISC_TO;
3355 
3356 	xprt->ops = &xs_tcp_ops;
3357 	xprt->timeout = &xs_tcp_default_timeout;
3358 
3359 	xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
3360 	if (args->reconnect_timeout)
3361 		xprt->max_reconnect_timeout = args->reconnect_timeout;
3362 
3363 	xprt->connect_timeout = xprt->timeout->to_initval *
3364 		(xprt->timeout->to_retries + 1);
3365 	if (args->connect_timeout)
3366 		xs_tcp_do_set_connect_timeout(xprt, args->connect_timeout);
3367 
3368 	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
3369 	INIT_WORK(&transport->error_worker, xs_error_handle);
3370 	INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
3371 
3372 	switch (addr->sa_family) {
3373 	case AF_INET:
3374 		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3375 			xprt_set_bound(xprt);
3376 
3377 		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
3378 		break;
3379 	case AF_INET6:
3380 		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3381 			xprt_set_bound(xprt);
3382 
3383 		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
3384 		break;
3385 	default:
3386 		ret = ERR_PTR(-EAFNOSUPPORT);
3387 		goto out_err;
3388 	}
3389 
3390 	if (xprt_bound(xprt))
3391 		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3392 				xprt->address_strings[RPC_DISPLAY_ADDR],
3393 				xprt->address_strings[RPC_DISPLAY_PORT],
3394 				xprt->address_strings[RPC_DISPLAY_PROTO]);
3395 	else
3396 		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3397 				xprt->address_strings[RPC_DISPLAY_ADDR],
3398 				xprt->address_strings[RPC_DISPLAY_PROTO]);
3399 
3400 	if (try_module_get(THIS_MODULE))
3401 		return xprt;
3402 	ret = ERR_PTR(-EINVAL);
3403 out_err:
3404 	xs_xprt_free(xprt);
3405 	return ret;
3406 }
3407 
3408 /**
3409  * xs_setup_tcp_tls - Set up transport to use a TCP with TLS
3410  * @args: rpc transport creation arguments
3411  *
3412  */
3413 static struct rpc_xprt *xs_setup_tcp_tls(struct xprt_create *args)
3414 {
3415 	struct sockaddr *addr = args->dstaddr;
3416 	struct rpc_xprt *xprt;
3417 	struct sock_xprt *transport;
3418 	struct rpc_xprt *ret;
3419 	unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
3420 
3421 	if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
3422 		max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
3423 
3424 	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3425 			     max_slot_table_size);
3426 	if (IS_ERR(xprt))
3427 		return xprt;
3428 	transport = container_of(xprt, struct sock_xprt, xprt);
3429 
3430 	xprt->prot = IPPROTO_TCP;
3431 	xprt->xprt_class = &xs_tcp_transport;
3432 	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3433 
3434 	xprt->bind_timeout = XS_BIND_TO;
3435 	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
3436 	xprt->idle_timeout = XS_IDLE_DISC_TO;
3437 
3438 	xprt->ops = &xs_tcp_ops;
3439 	xprt->timeout = &xs_tcp_default_timeout;
3440 
3441 	xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
3442 	xprt->connect_timeout = xprt->timeout->to_initval *
3443 		(xprt->timeout->to_retries + 1);
3444 
3445 	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
3446 	INIT_WORK(&transport->error_worker, xs_error_handle);
3447 
3448 	switch (args->xprtsec.policy) {
3449 	case RPC_XPRTSEC_TLS_ANON:
3450 	case RPC_XPRTSEC_TLS_X509:
3451 		xprt->xprtsec = args->xprtsec;
3452 		INIT_DELAYED_WORK(&transport->connect_worker,
3453 				  xs_tcp_tls_setup_socket);
3454 		break;
3455 	default:
3456 		ret = ERR_PTR(-EACCES);
3457 		goto out_err;
3458 	}
3459 
3460 	switch (addr->sa_family) {
3461 	case AF_INET:
3462 		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3463 			xprt_set_bound(xprt);
3464 
3465 		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
3466 		break;
3467 	case AF_INET6:
3468 		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3469 			xprt_set_bound(xprt);
3470 
3471 		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
3472 		break;
3473 	default:
3474 		ret = ERR_PTR(-EAFNOSUPPORT);
3475 		goto out_err;
3476 	}
3477 
3478 	if (xprt_bound(xprt))
3479 		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3480 			xprt->address_strings[RPC_DISPLAY_ADDR],
3481 			xprt->address_strings[RPC_DISPLAY_PORT],
3482 			xprt->address_strings[RPC_DISPLAY_PROTO]);
3483 	else
3484 		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3485 			xprt->address_strings[RPC_DISPLAY_ADDR],
3486 			xprt->address_strings[RPC_DISPLAY_PROTO]);
3487 
3488 	if (try_module_get(THIS_MODULE))
3489 		return xprt;
3490 	ret = ERR_PTR(-EINVAL);
3491 out_err:
3492 	xs_xprt_free(xprt);
3493 	return ret;
3494 }
3495 
3496 /**
3497  * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
3498  * @args: rpc transport creation arguments
3499  *
3500  */
3501 static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
3502 {
3503 	struct sockaddr *addr = args->dstaddr;
3504 	struct rpc_xprt *xprt;
3505 	struct sock_xprt *transport;
3506 	struct svc_sock *bc_sock;
3507 	struct rpc_xprt *ret;
3508 
3509 	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3510 			xprt_tcp_slot_table_entries);
3511 	if (IS_ERR(xprt))
3512 		return xprt;
3513 	transport = container_of(xprt, struct sock_xprt, xprt);
3514 
3515 	xprt->prot = IPPROTO_TCP;
3516 	xprt->xprt_class = &xs_bc_tcp_transport;
3517 	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3518 	xprt->timeout = &xs_tcp_default_timeout;
3519 
3520 	/* backchannel */
3521 	xprt_set_bound(xprt);
3522 	xprt->bind_timeout = 0;
3523 	xprt->reestablish_timeout = 0;
3524 	xprt->idle_timeout = 0;
3525 
3526 	xprt->ops = &bc_tcp_ops;
3527 
3528 	switch (addr->sa_family) {
3529 	case AF_INET:
3530 		xs_format_peer_addresses(xprt, "tcp",
3531 					 RPCBIND_NETID_TCP);
3532 		break;
3533 	case AF_INET6:
3534 		xs_format_peer_addresses(xprt, "tcp",
3535 				   RPCBIND_NETID_TCP6);
3536 		break;
3537 	default:
3538 		ret = ERR_PTR(-EAFNOSUPPORT);
3539 		goto out_err;
3540 	}
3541 
3542 	dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3543 			xprt->address_strings[RPC_DISPLAY_ADDR],
3544 			xprt->address_strings[RPC_DISPLAY_PORT],
3545 			xprt->address_strings[RPC_DISPLAY_PROTO]);
3546 
3547 	/*
3548 	 * Once we've associated a backchannel xprt with a connection,
3549 	 * we want to keep it around as long as the connection lasts,
3550 	 * in case we need to start using it for a backchannel again;
3551 	 * this reference won't be dropped until bc_xprt is destroyed.
3552 	 */
3553 	xprt_get(xprt);
3554 	args->bc_xprt->xpt_bc_xprt = xprt;
3555 	xprt->bc_xprt = args->bc_xprt;
3556 	bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3557 	transport->sock = bc_sock->sk_sock;
3558 	transport->inet = bc_sock->sk_sk;
3559 
3560 	/*
3561 	 * Since we don't want connections for the backchannel, we set
3562 	 * the xprt status to connected
3563 	 */
3564 	xprt_set_connected(xprt);
3565 
3566 	if (try_module_get(THIS_MODULE))
3567 		return xprt;
3568 
3569 	args->bc_xprt->xpt_bc_xprt = NULL;
3570 	args->bc_xprt->xpt_bc_xps = NULL;
3571 	xprt_put(xprt);
3572 	ret = ERR_PTR(-EINVAL);
3573 out_err:
3574 	xs_xprt_free(xprt);
3575 	return ret;
3576 }
3577 
3578 static struct xprt_class	xs_local_transport = {
3579 	.list		= LIST_HEAD_INIT(xs_local_transport.list),
3580 	.name		= "named UNIX socket",
3581 	.owner		= THIS_MODULE,
3582 	.ident		= XPRT_TRANSPORT_LOCAL,
3583 	.setup		= xs_setup_local,
3584 	.netid		= { "" },
3585 };
3586 
3587 static struct xprt_class	xs_udp_transport = {
3588 	.list		= LIST_HEAD_INIT(xs_udp_transport.list),
3589 	.name		= "udp",
3590 	.owner		= THIS_MODULE,
3591 	.ident		= XPRT_TRANSPORT_UDP,
3592 	.setup		= xs_setup_udp,
3593 	.netid		= { "udp", "udp6", "" },
3594 };
3595 
3596 static struct xprt_class	xs_tcp_transport = {
3597 	.list		= LIST_HEAD_INIT(xs_tcp_transport.list),
3598 	.name		= "tcp",
3599 	.owner		= THIS_MODULE,
3600 	.ident		= XPRT_TRANSPORT_TCP,
3601 	.setup		= xs_setup_tcp,
3602 	.netid		= { "tcp", "tcp6", "" },
3603 };
3604 
3605 static struct xprt_class	xs_tcp_tls_transport = {
3606 	.list		= LIST_HEAD_INIT(xs_tcp_tls_transport.list),
3607 	.name		= "tcp-with-tls",
3608 	.owner		= THIS_MODULE,
3609 	.ident		= XPRT_TRANSPORT_TCP_TLS,
3610 	.setup		= xs_setup_tcp_tls,
3611 	.netid		= { "tcp", "tcp6", "" },
3612 };
3613 
3614 static struct xprt_class	xs_bc_tcp_transport = {
3615 	.list		= LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3616 	.name		= "tcp NFSv4.1 backchannel",
3617 	.owner		= THIS_MODULE,
3618 	.ident		= XPRT_TRANSPORT_BC_TCP,
3619 	.setup		= xs_setup_bc_tcp,
3620 	.netid		= { "" },
3621 };
3622 
3623 /**
3624  * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3625  *
3626  */
3627 int init_socket_xprt(void)
3628 {
3629 	if (!sunrpc_table_header)
3630 		sunrpc_table_header = register_sysctl("sunrpc", xs_tunables_table);
3631 
3632 	xprt_register_transport(&xs_local_transport);
3633 	xprt_register_transport(&xs_udp_transport);
3634 	xprt_register_transport(&xs_tcp_transport);
3635 	xprt_register_transport(&xs_tcp_tls_transport);
3636 	xprt_register_transport(&xs_bc_tcp_transport);
3637 
3638 	return 0;
3639 }
3640 
3641 /**
3642  * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3643  *
3644  */
3645 void cleanup_socket_xprt(void)
3646 {
3647 	if (sunrpc_table_header) {
3648 		unregister_sysctl_table(sunrpc_table_header);
3649 		sunrpc_table_header = NULL;
3650 	}
3651 
3652 	xprt_unregister_transport(&xs_local_transport);
3653 	xprt_unregister_transport(&xs_udp_transport);
3654 	xprt_unregister_transport(&xs_tcp_transport);
3655 	xprt_unregister_transport(&xs_tcp_tls_transport);
3656 	xprt_unregister_transport(&xs_bc_tcp_transport);
3657 }
3658 
3659 static int param_set_portnr(const char *val, const struct kernel_param *kp)
3660 {
3661 	return param_set_uint_minmax(val, kp,
3662 			RPC_MIN_RESVPORT,
3663 			RPC_MAX_RESVPORT);
3664 }
3665 
3666 static const struct kernel_param_ops param_ops_portnr = {
3667 	.set = param_set_portnr,
3668 	.get = param_get_uint,
3669 };
3670 
3671 #define param_check_portnr(name, p) \
3672 	__param_check(name, p, unsigned int);
3673 
3674 module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3675 module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3676 
3677 static int param_set_slot_table_size(const char *val,
3678 				     const struct kernel_param *kp)
3679 {
3680 	return param_set_uint_minmax(val, kp,
3681 			RPC_MIN_SLOT_TABLE,
3682 			RPC_MAX_SLOT_TABLE);
3683 }
3684 
3685 static const struct kernel_param_ops param_ops_slot_table_size = {
3686 	.set = param_set_slot_table_size,
3687 	.get = param_get_uint,
3688 };
3689 
3690 #define param_check_slot_table_size(name, p) \
3691 	__param_check(name, p, unsigned int);
3692 
3693 static int param_set_max_slot_table_size(const char *val,
3694 				     const struct kernel_param *kp)
3695 {
3696 	return param_set_uint_minmax(val, kp,
3697 			RPC_MIN_SLOT_TABLE,
3698 			RPC_MAX_SLOT_TABLE_LIMIT);
3699 }
3700 
3701 static const struct kernel_param_ops param_ops_max_slot_table_size = {
3702 	.set = param_set_max_slot_table_size,
3703 	.get = param_get_uint,
3704 };
3705 
3706 #define param_check_max_slot_table_size(name, p) \
3707 	__param_check(name, p, unsigned int);
3708 
3709 module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3710 		   slot_table_size, 0644);
3711 module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3712 		   max_slot_table_size, 0644);
3713 module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3714 		   slot_table_size, 0644);
3715