xref: /linux/net/sunrpc/xprtsock.c (revision bb9ae1a66c85eeb626864efd812c62026e126ec0)
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_reset_srcport(struct sock_xprt *transport);
66 static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock);
67 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
68 		struct socket *sock);
69 
70 /*
71  * xprtsock tunables
72  */
73 static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
74 static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
75 static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
76 
77 static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
78 static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
79 
80 #define XS_TCP_LINGER_TO	(15U * HZ)
81 static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
82 
83 /*
84  * We can register our own files under /proc/sys/sunrpc by
85  * calling register_sysctl() again.  The files in that
86  * directory become the union of all files registered there.
87  *
88  * We simply need to make sure that we don't collide with
89  * someone else's file names!
90  */
91 
92 static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
93 static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
94 static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
95 static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
96 static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
97 
98 static struct ctl_table_header *sunrpc_table_header;
99 
100 static struct xprt_class xs_local_transport;
101 static struct xprt_class xs_udp_transport;
102 static struct xprt_class xs_tcp_transport;
103 static struct xprt_class xs_tcp_tls_transport;
104 static struct xprt_class xs_bc_tcp_transport;
105 
106 /*
107  * FIXME: changing the UDP slot table size should also resize the UDP
108  *        socket buffers for existing UDP transports
109  */
110 static struct ctl_table xs_tunables_table[] = {
111 	{
112 		.procname	= "udp_slot_table_entries",
113 		.data		= &xprt_udp_slot_table_entries,
114 		.maxlen		= sizeof(unsigned int),
115 		.mode		= 0644,
116 		.proc_handler	= proc_dointvec_minmax,
117 		.extra1		= &min_slot_table_size,
118 		.extra2		= &max_slot_table_size
119 	},
120 	{
121 		.procname	= "tcp_slot_table_entries",
122 		.data		= &xprt_tcp_slot_table_entries,
123 		.maxlen		= sizeof(unsigned int),
124 		.mode		= 0644,
125 		.proc_handler	= proc_dointvec_minmax,
126 		.extra1		= &min_slot_table_size,
127 		.extra2		= &max_slot_table_size
128 	},
129 	{
130 		.procname	= "tcp_max_slot_table_entries",
131 		.data		= &xprt_max_tcp_slot_table_entries,
132 		.maxlen		= sizeof(unsigned int),
133 		.mode		= 0644,
134 		.proc_handler	= proc_dointvec_minmax,
135 		.extra1		= &min_slot_table_size,
136 		.extra2		= &max_tcp_slot_table_limit
137 	},
138 	{
139 		.procname	= "min_resvport",
140 		.data		= &xprt_min_resvport,
141 		.maxlen		= sizeof(unsigned int),
142 		.mode		= 0644,
143 		.proc_handler	= proc_dointvec_minmax,
144 		.extra1		= &xprt_min_resvport_limit,
145 		.extra2		= &xprt_max_resvport_limit
146 	},
147 	{
148 		.procname	= "max_resvport",
149 		.data		= &xprt_max_resvport,
150 		.maxlen		= sizeof(unsigned int),
151 		.mode		= 0644,
152 		.proc_handler	= proc_dointvec_minmax,
153 		.extra1		= &xprt_min_resvport_limit,
154 		.extra2		= &xprt_max_resvport_limit
155 	},
156 	{
157 		.procname	= "tcp_fin_timeout",
158 		.data		= &xs_tcp_fin_timeout,
159 		.maxlen		= sizeof(xs_tcp_fin_timeout),
160 		.mode		= 0644,
161 		.proc_handler	= proc_dointvec_jiffies,
162 	},
163 };
164 
165 /*
166  * 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 static void xs_stream_abort_send_request(struct rpc_rqst *req)
887 {
888 	struct rpc_xprt *xprt = req->rq_xprt;
889 	struct sock_xprt *transport =
890 		container_of(xprt, struct sock_xprt, xprt);
891 
892 	if (transport->xmit.offset != 0 &&
893 	    !test_bit(XPRT_CLOSE_WAIT, &xprt->state))
894 		xprt_force_disconnect(xprt);
895 }
896 
897 /*
898  * Determine if the previous message in the stream was aborted before it
899  * could complete transmission.
900  */
901 static bool
902 xs_send_request_was_aborted(struct sock_xprt *transport, struct rpc_rqst *req)
903 {
904 	return transport->xmit.offset != 0 && req->rq_bytes_sent == 0;
905 }
906 
907 /*
908  * Return the stream record marker field for a record of length < 2^31-1
909  */
910 static rpc_fraghdr
911 xs_stream_record_marker(struct xdr_buf *xdr)
912 {
913 	if (!xdr->len)
914 		return 0;
915 	return cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | (u32)xdr->len);
916 }
917 
918 /**
919  * xs_local_send_request - write an RPC request to an AF_LOCAL socket
920  * @req: pointer to RPC request
921  *
922  * Return values:
923  *        0:	The request has been sent
924  *   EAGAIN:	The socket was blocked, please call again later to
925  *		complete the request
926  * ENOTCONN:	Caller needs to invoke connect logic then call again
927  *    other:	Some other error occurred, the request was not sent
928  */
929 static int xs_local_send_request(struct rpc_rqst *req)
930 {
931 	struct rpc_xprt *xprt = req->rq_xprt;
932 	struct sock_xprt *transport =
933 				container_of(xprt, struct sock_xprt, xprt);
934 	struct xdr_buf *xdr = &req->rq_snd_buf;
935 	rpc_fraghdr rm = xs_stream_record_marker(xdr);
936 	unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
937 	struct msghdr msg = {
938 		.msg_flags	= XS_SENDMSG_FLAGS,
939 	};
940 	bool vm_wait;
941 	unsigned int sent;
942 	int status;
943 
944 	/* Close the stream if the previous transmission was incomplete */
945 	if (xs_send_request_was_aborted(transport, req)) {
946 		xprt_force_disconnect(xprt);
947 		return -ENOTCONN;
948 	}
949 
950 	xs_pktdump("packet data:",
951 			req->rq_svec->iov_base, req->rq_svec->iov_len);
952 
953 	vm_wait = sk_stream_is_writeable(transport->inet) ? true : false;
954 
955 	req->rq_xtime = ktime_get();
956 	status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
957 				   transport->xmit.offset, rm, &sent);
958 	dprintk("RPC:       %s(%u) = %d\n",
959 			__func__, xdr->len - transport->xmit.offset, status);
960 
961 	if (likely(sent > 0) || status == 0) {
962 		transport->xmit.offset += sent;
963 		req->rq_bytes_sent = transport->xmit.offset;
964 		if (likely(req->rq_bytes_sent >= msglen)) {
965 			req->rq_xmit_bytes_sent += transport->xmit.offset;
966 			transport->xmit.offset = 0;
967 			return 0;
968 		}
969 		status = -EAGAIN;
970 		vm_wait = false;
971 	}
972 
973 	switch (status) {
974 	case -EAGAIN:
975 		status = xs_stream_nospace(req, vm_wait);
976 		break;
977 	default:
978 		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
979 			-status);
980 		fallthrough;
981 	case -EPIPE:
982 		xprt_force_disconnect(xprt);
983 		status = -ENOTCONN;
984 	}
985 
986 	return status;
987 }
988 
989 /**
990  * xs_udp_send_request - write an RPC request to a UDP socket
991  * @req: pointer to RPC request
992  *
993  * Return values:
994  *        0:	The request has been sent
995  *   EAGAIN:	The socket was blocked, please call again later to
996  *		complete the request
997  * ENOTCONN:	Caller needs to invoke connect logic then call again
998  *    other:	Some other error occurred, the request was not sent
999  */
1000 static int xs_udp_send_request(struct rpc_rqst *req)
1001 {
1002 	struct rpc_xprt *xprt = req->rq_xprt;
1003 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1004 	struct xdr_buf *xdr = &req->rq_snd_buf;
1005 	struct msghdr msg = {
1006 		.msg_name	= xs_addr(xprt),
1007 		.msg_namelen	= xprt->addrlen,
1008 		.msg_flags	= XS_SENDMSG_FLAGS,
1009 	};
1010 	unsigned int sent;
1011 	int status;
1012 
1013 	xs_pktdump("packet data:",
1014 				req->rq_svec->iov_base,
1015 				req->rq_svec->iov_len);
1016 
1017 	if (!xprt_bound(xprt))
1018 		return -ENOTCONN;
1019 
1020 	if (!xprt_request_get_cong(xprt, req))
1021 		return -EBADSLT;
1022 
1023 	status = xdr_alloc_bvec(xdr, rpc_task_gfp_mask());
1024 	if (status < 0)
1025 		return status;
1026 	req->rq_xtime = ktime_get();
1027 	status = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, 0, &sent);
1028 
1029 	dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
1030 			xdr->len, status);
1031 
1032 	/* firewall is blocking us, don't return -EAGAIN or we end up looping */
1033 	if (status == -EPERM)
1034 		goto process_status;
1035 
1036 	if (status == -EAGAIN && sock_writeable(transport->inet))
1037 		status = -ENOBUFS;
1038 
1039 	if (sent > 0 || status == 0) {
1040 		req->rq_xmit_bytes_sent += sent;
1041 		if (sent >= req->rq_slen)
1042 			return 0;
1043 		/* Still some bytes left; set up for a retry later. */
1044 		status = -EAGAIN;
1045 	}
1046 
1047 process_status:
1048 	switch (status) {
1049 	case -ENOTSOCK:
1050 		status = -ENOTCONN;
1051 		/* Should we call xs_close() here? */
1052 		break;
1053 	case -EAGAIN:
1054 		status = xs_sock_nospace(req);
1055 		break;
1056 	case -ENETUNREACH:
1057 	case -ENOBUFS:
1058 	case -EPIPE:
1059 	case -ECONNREFUSED:
1060 	case -EPERM:
1061 		/* When the server has died, an ICMP port unreachable message
1062 		 * prompts ECONNREFUSED. */
1063 		break;
1064 	default:
1065 		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1066 			-status);
1067 	}
1068 
1069 	return status;
1070 }
1071 
1072 /**
1073  * xs_tcp_send_request - write an RPC request to a TCP socket
1074  * @req: pointer to RPC request
1075  *
1076  * Return values:
1077  *        0:	The request has been sent
1078  *   EAGAIN:	The socket was blocked, please call again later to
1079  *		complete the request
1080  * ENOTCONN:	Caller needs to invoke connect logic then call again
1081  *    other:	Some other error occurred, the request was not sent
1082  *
1083  * XXX: In the case of soft timeouts, should we eventually give up
1084  *	if sendmsg is not able to make progress?
1085  */
1086 static int xs_tcp_send_request(struct rpc_rqst *req)
1087 {
1088 	struct rpc_xprt *xprt = req->rq_xprt;
1089 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1090 	struct xdr_buf *xdr = &req->rq_snd_buf;
1091 	rpc_fraghdr rm = xs_stream_record_marker(xdr);
1092 	unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
1093 	struct msghdr msg = {
1094 		.msg_flags	= XS_SENDMSG_FLAGS,
1095 	};
1096 	bool vm_wait;
1097 	unsigned int sent;
1098 	int status;
1099 
1100 	/* Close the stream if the previous transmission was incomplete */
1101 	if (xs_send_request_was_aborted(transport, req)) {
1102 		if (transport->sock != NULL)
1103 			kernel_sock_shutdown(transport->sock, SHUT_RDWR);
1104 		return -ENOTCONN;
1105 	}
1106 	if (!transport->inet)
1107 		return -ENOTCONN;
1108 
1109 	xs_pktdump("packet data:",
1110 				req->rq_svec->iov_base,
1111 				req->rq_svec->iov_len);
1112 
1113 	if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state))
1114 		xs_tcp_set_socket_timeouts(xprt, transport->sock);
1115 
1116 	xs_set_srcport(transport, transport->sock);
1117 
1118 	/* Continue transmitting the packet/record. We must be careful
1119 	 * to cope with writespace callbacks arriving _after_ we have
1120 	 * called sendmsg(). */
1121 	req->rq_xtime = ktime_get();
1122 	tcp_sock_set_cork(transport->inet, true);
1123 
1124 	vm_wait = sk_stream_is_writeable(transport->inet) ? true : false;
1125 
1126 	do {
1127 		status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
1128 					   transport->xmit.offset, rm, &sent);
1129 
1130 		dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
1131 				xdr->len - transport->xmit.offset, status);
1132 
1133 		/* If we've sent the entire packet, immediately
1134 		 * reset the count of bytes sent. */
1135 		transport->xmit.offset += sent;
1136 		req->rq_bytes_sent = transport->xmit.offset;
1137 		if (likely(req->rq_bytes_sent >= msglen)) {
1138 			req->rq_xmit_bytes_sent += transport->xmit.offset;
1139 			transport->xmit.offset = 0;
1140 			if (atomic_long_read(&xprt->xmit_queuelen) == 1)
1141 				tcp_sock_set_cork(transport->inet, false);
1142 			return 0;
1143 		}
1144 
1145 		WARN_ON_ONCE(sent == 0 && status == 0);
1146 
1147 		if (sent > 0)
1148 			vm_wait = false;
1149 
1150 	} while (status == 0);
1151 
1152 	switch (status) {
1153 	case -ENOTSOCK:
1154 		status = -ENOTCONN;
1155 		/* Should we call xs_close() here? */
1156 		break;
1157 	case -EAGAIN:
1158 		status = xs_stream_nospace(req, vm_wait);
1159 		break;
1160 	case -ECONNRESET:
1161 	case -ECONNREFUSED:
1162 	case -ENOTCONN:
1163 	case -EADDRINUSE:
1164 	case -ENOBUFS:
1165 	case -EPIPE:
1166 		break;
1167 	default:
1168 		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1169 			-status);
1170 	}
1171 
1172 	return status;
1173 }
1174 
1175 static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1176 {
1177 	transport->old_data_ready = sk->sk_data_ready;
1178 	transport->old_state_change = sk->sk_state_change;
1179 	transport->old_write_space = sk->sk_write_space;
1180 	transport->old_error_report = sk->sk_error_report;
1181 }
1182 
1183 static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1184 {
1185 	sk->sk_data_ready = transport->old_data_ready;
1186 	sk->sk_state_change = transport->old_state_change;
1187 	sk->sk_write_space = transport->old_write_space;
1188 	sk->sk_error_report = transport->old_error_report;
1189 }
1190 
1191 static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
1192 {
1193 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1194 
1195 	transport->xprt_err = 0;
1196 	clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1197 	clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state);
1198 	clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state);
1199 	clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state);
1200 	clear_bit(XPRT_SOCK_NOSPACE, &transport->sock_state);
1201 }
1202 
1203 static void xs_run_error_worker(struct sock_xprt *transport, unsigned int nr)
1204 {
1205 	set_bit(nr, &transport->sock_state);
1206 	queue_work(xprtiod_workqueue, &transport->error_worker);
1207 }
1208 
1209 static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
1210 {
1211 	xprt->connect_cookie++;
1212 	smp_mb__before_atomic();
1213 	clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1214 	clear_bit(XPRT_CLOSING, &xprt->state);
1215 	xs_sock_reset_state_flags(xprt);
1216 	smp_mb__after_atomic();
1217 }
1218 
1219 /**
1220  * xs_error_report - callback to handle TCP socket state errors
1221  * @sk: socket
1222  *
1223  * Note: we don't call sock_error() since there may be a rpc_task
1224  * using the socket, and so we don't want to clear sk->sk_err.
1225  */
1226 static void xs_error_report(struct sock *sk)
1227 {
1228 	struct sock_xprt *transport;
1229 	struct rpc_xprt *xprt;
1230 
1231 	if (!(xprt = xprt_from_sock(sk)))
1232 		return;
1233 
1234 	transport = container_of(xprt, struct sock_xprt, xprt);
1235 	transport->xprt_err = -sk->sk_err;
1236 	if (transport->xprt_err == 0)
1237 		return;
1238 	dprintk("RPC:       xs_error_report client %p, error=%d...\n",
1239 			xprt, -transport->xprt_err);
1240 	trace_rpc_socket_error(xprt, sk->sk_socket, transport->xprt_err);
1241 
1242 	/* barrier ensures xprt_err is set before XPRT_SOCK_WAKE_ERROR */
1243 	smp_mb__before_atomic();
1244 	xs_run_error_worker(transport, XPRT_SOCK_WAKE_ERROR);
1245 }
1246 
1247 static void xs_reset_transport(struct sock_xprt *transport)
1248 {
1249 	struct socket *sock = transport->sock;
1250 	struct sock *sk = transport->inet;
1251 	struct rpc_xprt *xprt = &transport->xprt;
1252 	struct file *filp = transport->file;
1253 
1254 	if (sk == NULL)
1255 		return;
1256 	/*
1257 	 * Make sure we're calling this in a context from which it is safe
1258 	 * to call __fput_sync(). In practice that means rpciod and the
1259 	 * system workqueue.
1260 	 */
1261 	if (!(current->flags & PF_WQ_WORKER)) {
1262 		WARN_ON_ONCE(1);
1263 		set_bit(XPRT_CLOSE_WAIT, &xprt->state);
1264 		return;
1265 	}
1266 
1267 	if (atomic_read(&transport->xprt.swapper))
1268 		sk_clear_memalloc(sk);
1269 
1270 	tls_handshake_cancel(sk);
1271 
1272 	kernel_sock_shutdown(sock, SHUT_RDWR);
1273 
1274 	mutex_lock(&transport->recv_mutex);
1275 	lock_sock(sk);
1276 	transport->inet = NULL;
1277 	transport->sock = NULL;
1278 	transport->file = NULL;
1279 
1280 	sk->sk_user_data = NULL;
1281 
1282 	xs_restore_old_callbacks(transport, sk);
1283 	xprt_clear_connected(xprt);
1284 	xs_sock_reset_connection_flags(xprt);
1285 	/* Reset stream record info */
1286 	xs_stream_reset_connect(transport);
1287 	release_sock(sk);
1288 	mutex_unlock(&transport->recv_mutex);
1289 
1290 	trace_rpc_socket_close(xprt, sock);
1291 	__fput_sync(filp);
1292 
1293 	xprt_disconnect_done(xprt);
1294 }
1295 
1296 /**
1297  * xs_close - close a socket
1298  * @xprt: transport
1299  *
1300  * This is used when all requests are complete; ie, no DRC state remains
1301  * on the server we want to save.
1302  *
1303  * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
1304  * xs_reset_transport() zeroing the socket from underneath a writer.
1305  */
1306 static void xs_close(struct rpc_xprt *xprt)
1307 {
1308 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1309 
1310 	dprintk("RPC:       xs_close xprt %p\n", xprt);
1311 
1312 	if (transport->sock)
1313 		tls_handshake_close(transport->sock);
1314 	xs_reset_transport(transport);
1315 	xprt->reestablish_timeout = 0;
1316 }
1317 
1318 static void xs_inject_disconnect(struct rpc_xprt *xprt)
1319 {
1320 	dprintk("RPC:       injecting transport disconnect on xprt=%p\n",
1321 		xprt);
1322 	xprt_disconnect_done(xprt);
1323 }
1324 
1325 static void xs_xprt_free(struct rpc_xprt *xprt)
1326 {
1327 	xs_free_peer_addresses(xprt);
1328 	xprt_free(xprt);
1329 }
1330 
1331 /**
1332  * xs_destroy - prepare to shutdown a transport
1333  * @xprt: doomed transport
1334  *
1335  */
1336 static void xs_destroy(struct rpc_xprt *xprt)
1337 {
1338 	struct sock_xprt *transport = container_of(xprt,
1339 			struct sock_xprt, xprt);
1340 	dprintk("RPC:       xs_destroy xprt %p\n", xprt);
1341 
1342 	cancel_delayed_work_sync(&transport->connect_worker);
1343 	xs_close(xprt);
1344 	cancel_work_sync(&transport->recv_worker);
1345 	cancel_work_sync(&transport->error_worker);
1346 	xs_xprt_free(xprt);
1347 	module_put(THIS_MODULE);
1348 }
1349 
1350 /**
1351  * xs_udp_data_read_skb - receive callback for UDP sockets
1352  * @xprt: transport
1353  * @sk: socket
1354  * @skb: skbuff
1355  *
1356  */
1357 static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
1358 		struct sock *sk,
1359 		struct sk_buff *skb)
1360 {
1361 	struct rpc_task *task;
1362 	struct rpc_rqst *rovr;
1363 	int repsize, copied;
1364 	u32 _xid;
1365 	__be32 *xp;
1366 
1367 	repsize = skb->len;
1368 	if (repsize < 4) {
1369 		dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
1370 		return;
1371 	}
1372 
1373 	/* Copy the XID from the skb... */
1374 	xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
1375 	if (xp == NULL)
1376 		return;
1377 
1378 	/* Look up and lock the request corresponding to the given XID */
1379 	spin_lock(&xprt->queue_lock);
1380 	rovr = xprt_lookup_rqst(xprt, *xp);
1381 	if (!rovr)
1382 		goto out_unlock;
1383 	xprt_pin_rqst(rovr);
1384 	xprt_update_rtt(rovr->rq_task);
1385 	spin_unlock(&xprt->queue_lock);
1386 	task = rovr->rq_task;
1387 
1388 	if ((copied = rovr->rq_private_buf.buflen) > repsize)
1389 		copied = repsize;
1390 
1391 	/* Suck it into the iovec, verify checksum if not done by hw. */
1392 	if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1393 		spin_lock(&xprt->queue_lock);
1394 		__UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
1395 		goto out_unpin;
1396 	}
1397 
1398 
1399 	spin_lock(&xprt->transport_lock);
1400 	xprt_adjust_cwnd(xprt, task, copied);
1401 	spin_unlock(&xprt->transport_lock);
1402 	spin_lock(&xprt->queue_lock);
1403 	xprt_complete_rqst(task, copied);
1404 	__UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
1405 out_unpin:
1406 	xprt_unpin_rqst(rovr);
1407  out_unlock:
1408 	spin_unlock(&xprt->queue_lock);
1409 }
1410 
1411 static void xs_udp_data_receive(struct sock_xprt *transport)
1412 {
1413 	struct sk_buff *skb;
1414 	struct sock *sk;
1415 	int err;
1416 
1417 	mutex_lock(&transport->recv_mutex);
1418 	sk = transport->inet;
1419 	if (sk == NULL)
1420 		goto out;
1421 	for (;;) {
1422 		skb = skb_recv_udp(sk, MSG_DONTWAIT, &err);
1423 		if (skb == NULL)
1424 			break;
1425 		xs_udp_data_read_skb(&transport->xprt, sk, skb);
1426 		consume_skb(skb);
1427 		cond_resched();
1428 	}
1429 	xs_poll_check_readable(transport);
1430 out:
1431 	mutex_unlock(&transport->recv_mutex);
1432 }
1433 
1434 static void xs_udp_data_receive_workfn(struct work_struct *work)
1435 {
1436 	struct sock_xprt *transport =
1437 		container_of(work, struct sock_xprt, recv_worker);
1438 	unsigned int pflags = memalloc_nofs_save();
1439 
1440 	xs_udp_data_receive(transport);
1441 	memalloc_nofs_restore(pflags);
1442 }
1443 
1444 /**
1445  * xs_data_ready - "data ready" callback for sockets
1446  * @sk: socket with data to read
1447  *
1448  */
1449 static void xs_data_ready(struct sock *sk)
1450 {
1451 	struct rpc_xprt *xprt;
1452 
1453 	trace_sk_data_ready(sk);
1454 
1455 	xprt = xprt_from_sock(sk);
1456 	if (xprt != NULL) {
1457 		struct sock_xprt *transport = container_of(xprt,
1458 				struct sock_xprt, xprt);
1459 
1460 		trace_xs_data_ready(xprt);
1461 
1462 		transport->old_data_ready(sk);
1463 
1464 		if (test_bit(XPRT_SOCK_IGNORE_RECV, &transport->sock_state))
1465 			return;
1466 
1467 		/* Any data means we had a useful conversation, so
1468 		 * then we don't need to delay the next reconnect
1469 		 */
1470 		if (xprt->reestablish_timeout)
1471 			xprt->reestablish_timeout = 0;
1472 		if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1473 			queue_work(xprtiod_workqueue, &transport->recv_worker);
1474 	}
1475 }
1476 
1477 /*
1478  * Helper function to force a TCP close if the server is sending
1479  * junk and/or it has put us in CLOSE_WAIT
1480  */
1481 static void xs_tcp_force_close(struct rpc_xprt *xprt)
1482 {
1483 	xprt_force_disconnect(xprt);
1484 }
1485 
1486 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1487 static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
1488 {
1489 	return PAGE_SIZE;
1490 }
1491 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1492 
1493 /**
1494  * xs_local_state_change - callback to handle AF_LOCAL socket state changes
1495  * @sk: socket whose state has changed
1496  *
1497  */
1498 static void xs_local_state_change(struct sock *sk)
1499 {
1500 	struct rpc_xprt *xprt;
1501 	struct sock_xprt *transport;
1502 
1503 	if (!(xprt = xprt_from_sock(sk)))
1504 		return;
1505 	transport = container_of(xprt, struct sock_xprt, xprt);
1506 	if (sk->sk_shutdown & SHUTDOWN_MASK) {
1507 		clear_bit(XPRT_CONNECTED, &xprt->state);
1508 		/* Trigger the socket release */
1509 		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1510 	}
1511 }
1512 
1513 /**
1514  * xs_tcp_state_change - callback to handle TCP socket state changes
1515  * @sk: socket whose state has changed
1516  *
1517  */
1518 static void xs_tcp_state_change(struct sock *sk)
1519 {
1520 	struct rpc_xprt *xprt;
1521 	struct sock_xprt *transport;
1522 
1523 	if (!(xprt = xprt_from_sock(sk)))
1524 		return;
1525 	dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1526 	dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1527 			sk->sk_state, xprt_connected(xprt),
1528 			sock_flag(sk, SOCK_DEAD),
1529 			sock_flag(sk, SOCK_ZAPPED),
1530 			sk->sk_shutdown);
1531 
1532 	transport = container_of(xprt, struct sock_xprt, xprt);
1533 	trace_rpc_socket_state_change(xprt, sk->sk_socket);
1534 	switch (sk->sk_state) {
1535 	case TCP_ESTABLISHED:
1536 		if (!xprt_test_and_set_connected(xprt)) {
1537 			xprt->connect_cookie++;
1538 			clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
1539 			xprt_clear_connecting(xprt);
1540 
1541 			xprt->stat.connect_count++;
1542 			xprt->stat.connect_time += (long)jiffies -
1543 						   xprt->stat.connect_start;
1544 			xs_run_error_worker(transport, XPRT_SOCK_WAKE_PENDING);
1545 		}
1546 		break;
1547 	case TCP_FIN_WAIT1:
1548 		/* The client initiated a shutdown of the socket */
1549 		xprt->connect_cookie++;
1550 		xprt->reestablish_timeout = 0;
1551 		set_bit(XPRT_CLOSING, &xprt->state);
1552 		smp_mb__before_atomic();
1553 		clear_bit(XPRT_CONNECTED, &xprt->state);
1554 		clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1555 		smp_mb__after_atomic();
1556 		break;
1557 	case TCP_CLOSE_WAIT:
1558 		/* The server initiated a shutdown of the socket */
1559 		xprt->connect_cookie++;
1560 		clear_bit(XPRT_CONNECTED, &xprt->state);
1561 		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1562 		fallthrough;
1563 	case TCP_CLOSING:
1564 		/*
1565 		 * If the server closed down the connection, make sure that
1566 		 * we back off before reconnecting
1567 		 */
1568 		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1569 			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1570 		break;
1571 	case TCP_LAST_ACK:
1572 		set_bit(XPRT_CLOSING, &xprt->state);
1573 		smp_mb__before_atomic();
1574 		clear_bit(XPRT_CONNECTED, &xprt->state);
1575 		smp_mb__after_atomic();
1576 		break;
1577 	case TCP_CLOSE:
1578 		if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
1579 				       &transport->sock_state)) {
1580 			xs_reset_srcport(transport);
1581 			xprt_clear_connecting(xprt);
1582 		}
1583 		clear_bit(XPRT_CLOSING, &xprt->state);
1584 		/* Trigger the socket release */
1585 		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1586 	}
1587 }
1588 
1589 static void xs_write_space(struct sock *sk)
1590 {
1591 	struct sock_xprt *transport;
1592 	struct rpc_xprt *xprt;
1593 
1594 	if (!sk->sk_socket)
1595 		return;
1596 	clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1597 
1598 	if (unlikely(!(xprt = xprt_from_sock(sk))))
1599 		return;
1600 	transport = container_of(xprt, struct sock_xprt, xprt);
1601 	if (!test_and_clear_bit(XPRT_SOCK_NOSPACE, &transport->sock_state))
1602 		return;
1603 	xs_run_error_worker(transport, XPRT_SOCK_WAKE_WRITE);
1604 	sk->sk_write_pending--;
1605 }
1606 
1607 /**
1608  * xs_udp_write_space - callback invoked when socket buffer space
1609  *                             becomes available
1610  * @sk: socket whose state has changed
1611  *
1612  * Called when more output buffer space is available for this socket.
1613  * We try not to wake our writers until they can make "significant"
1614  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1615  * with a bunch of small requests.
1616  */
1617 static void xs_udp_write_space(struct sock *sk)
1618 {
1619 	/* from net/core/sock.c:sock_def_write_space */
1620 	if (sock_writeable(sk))
1621 		xs_write_space(sk);
1622 }
1623 
1624 /**
1625  * xs_tcp_write_space - callback invoked when socket buffer space
1626  *                             becomes available
1627  * @sk: socket whose state has changed
1628  *
1629  * Called when more output buffer space is available for this socket.
1630  * We try not to wake our writers until they can make "significant"
1631  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1632  * with a bunch of small requests.
1633  */
1634 static void xs_tcp_write_space(struct sock *sk)
1635 {
1636 	/* from net/core/stream.c:sk_stream_write_space */
1637 	if (sk_stream_is_writeable(sk))
1638 		xs_write_space(sk);
1639 }
1640 
1641 static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1642 {
1643 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1644 	struct sock *sk = transport->inet;
1645 
1646 	if (transport->rcvsize) {
1647 		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1648 		sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1649 	}
1650 	if (transport->sndsize) {
1651 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1652 		sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1653 		sk->sk_write_space(sk);
1654 	}
1655 }
1656 
1657 /**
1658  * xs_udp_set_buffer_size - set send and receive limits
1659  * @xprt: generic transport
1660  * @sndsize: requested size of send buffer, in bytes
1661  * @rcvsize: requested size of receive buffer, in bytes
1662  *
1663  * Set socket send and receive buffer size limits.
1664  */
1665 static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1666 {
1667 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1668 
1669 	transport->sndsize = 0;
1670 	if (sndsize)
1671 		transport->sndsize = sndsize + 1024;
1672 	transport->rcvsize = 0;
1673 	if (rcvsize)
1674 		transport->rcvsize = rcvsize + 1024;
1675 
1676 	xs_udp_do_set_buffer_size(xprt);
1677 }
1678 
1679 /**
1680  * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1681  * @xprt: controlling transport
1682  * @task: task that timed out
1683  *
1684  * Adjust the congestion window after a retransmit timeout has occurred.
1685  */
1686 static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1687 {
1688 	spin_lock(&xprt->transport_lock);
1689 	xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1690 	spin_unlock(&xprt->transport_lock);
1691 }
1692 
1693 static int xs_get_random_port(void)
1694 {
1695 	unsigned short min = xprt_min_resvport, max = xprt_max_resvport;
1696 	unsigned short range;
1697 	unsigned short rand;
1698 
1699 	if (max < min)
1700 		return -EADDRINUSE;
1701 	range = max - min + 1;
1702 	rand = get_random_u32_below(range);
1703 	return rand + min;
1704 }
1705 
1706 static unsigned short xs_sock_getport(struct socket *sock)
1707 {
1708 	struct sockaddr_storage buf;
1709 	unsigned short port = 0;
1710 
1711 	if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0)
1712 		goto out;
1713 	switch (buf.ss_family) {
1714 	case AF_INET6:
1715 		port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1716 		break;
1717 	case AF_INET:
1718 		port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1719 	}
1720 out:
1721 	return port;
1722 }
1723 
1724 /**
1725  * xs_set_port - reset the port number in the remote endpoint address
1726  * @xprt: generic transport
1727  * @port: new port number
1728  *
1729  */
1730 static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1731 {
1732 	dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1733 
1734 	rpc_set_port(xs_addr(xprt), port);
1735 	xs_update_peer_port(xprt);
1736 }
1737 
1738 static void xs_reset_srcport(struct sock_xprt *transport)
1739 {
1740 	transport->srcport = 0;
1741 }
1742 
1743 static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1744 {
1745 	if (transport->srcport == 0 && transport->xprt.reuseport)
1746 		transport->srcport = xs_sock_getport(sock);
1747 }
1748 
1749 static int xs_get_srcport(struct sock_xprt *transport)
1750 {
1751 	int port = transport->srcport;
1752 
1753 	if (port == 0 && transport->xprt.resvport)
1754 		port = xs_get_random_port();
1755 	return port;
1756 }
1757 
1758 static unsigned short xs_sock_srcport(struct rpc_xprt *xprt)
1759 {
1760 	struct sock_xprt *sock = container_of(xprt, struct sock_xprt, xprt);
1761 	unsigned short ret = 0;
1762 	mutex_lock(&sock->recv_mutex);
1763 	if (sock->sock)
1764 		ret = xs_sock_getport(sock->sock);
1765 	mutex_unlock(&sock->recv_mutex);
1766 	return ret;
1767 }
1768 
1769 static int xs_sock_srcaddr(struct rpc_xprt *xprt, char *buf, size_t buflen)
1770 {
1771 	struct sock_xprt *sock = container_of(xprt, struct sock_xprt, xprt);
1772 	union {
1773 		struct sockaddr sa;
1774 		struct sockaddr_storage st;
1775 	} saddr;
1776 	int ret = -ENOTCONN;
1777 
1778 	mutex_lock(&sock->recv_mutex);
1779 	if (sock->sock) {
1780 		ret = kernel_getsockname(sock->sock, &saddr.sa);
1781 		if (ret >= 0)
1782 			ret = snprintf(buf, buflen, "%pISc", &saddr.sa);
1783 	}
1784 	mutex_unlock(&sock->recv_mutex);
1785 	return ret;
1786 }
1787 
1788 static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1789 {
1790 	if (transport->srcport != 0)
1791 		transport->srcport = 0;
1792 	if (!transport->xprt.resvport)
1793 		return 0;
1794 	if (port <= xprt_min_resvport || port > xprt_max_resvport)
1795 		return xprt_max_resvport;
1796 	return --port;
1797 }
1798 static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1799 {
1800 	struct sockaddr_storage myaddr;
1801 	int err, nloop = 0;
1802 	int port = xs_get_srcport(transport);
1803 	unsigned short last;
1804 
1805 	/*
1806 	 * If we are asking for any ephemeral port (i.e. port == 0 &&
1807 	 * transport->xprt.resvport == 0), don't bind.  Let the local
1808 	 * port selection happen implicitly when the socket is used
1809 	 * (for example at connect time).
1810 	 *
1811 	 * This ensures that we can continue to establish TCP
1812 	 * connections even when all local ephemeral ports are already
1813 	 * a part of some TCP connection.  This makes no difference
1814 	 * for UDP sockets, but also doesn't harm them.
1815 	 *
1816 	 * If we're asking for any reserved port (i.e. port == 0 &&
1817 	 * transport->xprt.resvport == 1) xs_get_srcport above will
1818 	 * ensure that port is non-zero and we will bind as needed.
1819 	 */
1820 	if (port <= 0)
1821 		return port;
1822 
1823 	memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1824 	do {
1825 		rpc_set_port((struct sockaddr *)&myaddr, port);
1826 		err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1827 				transport->xprt.addrlen);
1828 		if (err == 0) {
1829 			if (transport->xprt.reuseport)
1830 				transport->srcport = port;
1831 			break;
1832 		}
1833 		last = port;
1834 		port = xs_next_srcport(transport, port);
1835 		if (port > last)
1836 			nloop++;
1837 	} while (err == -EADDRINUSE && nloop != 2);
1838 
1839 	if (myaddr.ss_family == AF_INET)
1840 		dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1841 				&((struct sockaddr_in *)&myaddr)->sin_addr,
1842 				port, err ? "failed" : "ok", err);
1843 	else
1844 		dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1845 				&((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1846 				port, err ? "failed" : "ok", err);
1847 	return err;
1848 }
1849 
1850 /*
1851  * We don't support autobind on AF_LOCAL sockets
1852  */
1853 static void xs_local_rpcbind(struct rpc_task *task)
1854 {
1855 	xprt_set_bound(task->tk_xprt);
1856 }
1857 
1858 static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1859 {
1860 }
1861 
1862 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1863 static struct lock_class_key xs_key[3];
1864 static struct lock_class_key xs_slock_key[3];
1865 
1866 static inline void xs_reclassify_socketu(struct socket *sock)
1867 {
1868 	struct sock *sk = sock->sk;
1869 
1870 	sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1871 		&xs_slock_key[0], "sk_lock-AF_LOCAL-RPC", &xs_key[0]);
1872 }
1873 
1874 static inline void xs_reclassify_socket4(struct socket *sock)
1875 {
1876 	struct sock *sk = sock->sk;
1877 
1878 	sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1879 		&xs_slock_key[1], "sk_lock-AF_INET-RPC", &xs_key[1]);
1880 }
1881 
1882 static inline void xs_reclassify_socket6(struct socket *sock)
1883 {
1884 	struct sock *sk = sock->sk;
1885 
1886 	sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1887 		&xs_slock_key[2], "sk_lock-AF_INET6-RPC", &xs_key[2]);
1888 }
1889 
1890 static inline void xs_reclassify_socket(int family, struct socket *sock)
1891 {
1892 	if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
1893 		return;
1894 
1895 	switch (family) {
1896 	case AF_LOCAL:
1897 		xs_reclassify_socketu(sock);
1898 		break;
1899 	case AF_INET:
1900 		xs_reclassify_socket4(sock);
1901 		break;
1902 	case AF_INET6:
1903 		xs_reclassify_socket6(sock);
1904 		break;
1905 	}
1906 }
1907 #else
1908 static inline void xs_reclassify_socket(int family, struct socket *sock)
1909 {
1910 }
1911 #endif
1912 
1913 static void xs_dummy_setup_socket(struct work_struct *work)
1914 {
1915 }
1916 
1917 static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1918 		struct sock_xprt *transport, int family, int type,
1919 		int protocol, bool reuseport)
1920 {
1921 	struct file *filp;
1922 	struct socket *sock;
1923 	int err;
1924 
1925 	err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1926 	if (err < 0) {
1927 		dprintk("RPC:       can't create %d transport socket (%d).\n",
1928 				protocol, -err);
1929 		goto out;
1930 	}
1931 	xs_reclassify_socket(family, sock);
1932 
1933 	if (reuseport)
1934 		sock_set_reuseport(sock->sk);
1935 
1936 	err = xs_bind(transport, sock);
1937 	if (err) {
1938 		sock_release(sock);
1939 		goto out;
1940 	}
1941 
1942 	filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1943 	if (IS_ERR(filp))
1944 		return ERR_CAST(filp);
1945 	transport->file = filp;
1946 
1947 	return sock;
1948 out:
1949 	return ERR_PTR(err);
1950 }
1951 
1952 static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1953 				      struct socket *sock)
1954 {
1955 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1956 									xprt);
1957 
1958 	if (!transport->inet) {
1959 		struct sock *sk = sock->sk;
1960 
1961 		lock_sock(sk);
1962 
1963 		xs_save_old_callbacks(transport, sk);
1964 
1965 		sk->sk_user_data = xprt;
1966 		sk->sk_data_ready = xs_data_ready;
1967 		sk->sk_write_space = xs_udp_write_space;
1968 		sk->sk_state_change = xs_local_state_change;
1969 		sk->sk_error_report = xs_error_report;
1970 		sk->sk_use_task_frag = false;
1971 
1972 		xprt_clear_connected(xprt);
1973 
1974 		/* Reset to new socket */
1975 		transport->sock = sock;
1976 		transport->inet = sk;
1977 
1978 		release_sock(sk);
1979 	}
1980 
1981 	xs_stream_start_connect(transport);
1982 
1983 	return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1984 }
1985 
1986 /**
1987  * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1988  * @transport: socket transport to connect
1989  */
1990 static int xs_local_setup_socket(struct sock_xprt *transport)
1991 {
1992 	struct rpc_xprt *xprt = &transport->xprt;
1993 	struct file *filp;
1994 	struct socket *sock;
1995 	int status;
1996 
1997 	status = __sock_create(xprt->xprt_net, AF_LOCAL,
1998 					SOCK_STREAM, 0, &sock, 1);
1999 	if (status < 0) {
2000 		dprintk("RPC:       can't create AF_LOCAL "
2001 			"transport socket (%d).\n", -status);
2002 		goto out;
2003 	}
2004 	xs_reclassify_socket(AF_LOCAL, sock);
2005 
2006 	filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
2007 	if (IS_ERR(filp)) {
2008 		status = PTR_ERR(filp);
2009 		goto out;
2010 	}
2011 	transport->file = filp;
2012 
2013 	dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
2014 			xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2015 
2016 	status = xs_local_finish_connecting(xprt, sock);
2017 	trace_rpc_socket_connect(xprt, sock, status);
2018 	switch (status) {
2019 	case 0:
2020 		dprintk("RPC:       xprt %p connected to %s\n",
2021 				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2022 		xprt->stat.connect_count++;
2023 		xprt->stat.connect_time += (long)jiffies -
2024 					   xprt->stat.connect_start;
2025 		xprt_set_connected(xprt);
2026 		break;
2027 	case -ENOBUFS:
2028 		break;
2029 	case -ENOENT:
2030 		dprintk("RPC:       xprt %p: socket %s does not exist\n",
2031 				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2032 		break;
2033 	case -ECONNREFUSED:
2034 		dprintk("RPC:       xprt %p: connection refused for %s\n",
2035 				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2036 		break;
2037 	default:
2038 		printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
2039 				__func__, -status,
2040 				xprt->address_strings[RPC_DISPLAY_ADDR]);
2041 	}
2042 
2043 out:
2044 	xprt_clear_connecting(xprt);
2045 	xprt_wake_pending_tasks(xprt, status);
2046 	return status;
2047 }
2048 
2049 static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2050 {
2051 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2052 	int ret;
2053 
2054 	if (transport->file)
2055 		goto force_disconnect;
2056 
2057 	if (RPC_IS_ASYNC(task)) {
2058 		/*
2059 		 * We want the AF_LOCAL connect to be resolved in the
2060 		 * filesystem namespace of the process making the rpc
2061 		 * call.  Thus we connect synchronously.
2062 		 *
2063 		 * If we want to support asynchronous AF_LOCAL calls,
2064 		 * we'll need to figure out how to pass a namespace to
2065 		 * connect.
2066 		 */
2067 		rpc_task_set_rpc_status(task, -ENOTCONN);
2068 		goto out_wake;
2069 	}
2070 	ret = xs_local_setup_socket(transport);
2071 	if (ret && !RPC_IS_SOFTCONN(task))
2072 		msleep_interruptible(15000);
2073 	return;
2074 force_disconnect:
2075 	xprt_force_disconnect(xprt);
2076 out_wake:
2077 	xprt_clear_connecting(xprt);
2078 	xprt_wake_pending_tasks(xprt, -ENOTCONN);
2079 }
2080 
2081 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
2082 /*
2083  * Note that this should be called with XPRT_LOCKED held, or recv_mutex
2084  * held, or when we otherwise know that we have exclusive access to the
2085  * socket, to guard against races with xs_reset_transport.
2086  */
2087 static void xs_set_memalloc(struct rpc_xprt *xprt)
2088 {
2089 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
2090 			xprt);
2091 
2092 	/*
2093 	 * If there's no sock, then we have nothing to set. The
2094 	 * reconnecting process will get it for us.
2095 	 */
2096 	if (!transport->inet)
2097 		return;
2098 	if (atomic_read(&xprt->swapper))
2099 		sk_set_memalloc(transport->inet);
2100 }
2101 
2102 /**
2103  * xs_enable_swap - Tag this transport as being used for swap.
2104  * @xprt: transport to tag
2105  *
2106  * Take a reference to this transport on behalf of the rpc_clnt, and
2107  * optionally mark it for swapping if it wasn't already.
2108  */
2109 static int
2110 xs_enable_swap(struct rpc_xprt *xprt)
2111 {
2112 	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2113 
2114 	mutex_lock(&xs->recv_mutex);
2115 	if (atomic_inc_return(&xprt->swapper) == 1 &&
2116 	    xs->inet)
2117 		sk_set_memalloc(xs->inet);
2118 	mutex_unlock(&xs->recv_mutex);
2119 	return 0;
2120 }
2121 
2122 /**
2123  * xs_disable_swap - Untag this transport as being used for swap.
2124  * @xprt: transport to tag
2125  *
2126  * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
2127  * swapper refcount goes to 0, untag the socket as a memalloc socket.
2128  */
2129 static void
2130 xs_disable_swap(struct rpc_xprt *xprt)
2131 {
2132 	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2133 
2134 	mutex_lock(&xs->recv_mutex);
2135 	if (atomic_dec_and_test(&xprt->swapper) &&
2136 	    xs->inet)
2137 		sk_clear_memalloc(xs->inet);
2138 	mutex_unlock(&xs->recv_mutex);
2139 }
2140 #else
2141 static void xs_set_memalloc(struct rpc_xprt *xprt)
2142 {
2143 }
2144 
2145 static int
2146 xs_enable_swap(struct rpc_xprt *xprt)
2147 {
2148 	return -EINVAL;
2149 }
2150 
2151 static void
2152 xs_disable_swap(struct rpc_xprt *xprt)
2153 {
2154 }
2155 #endif
2156 
2157 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2158 {
2159 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2160 
2161 	if (!transport->inet) {
2162 		struct sock *sk = sock->sk;
2163 
2164 		lock_sock(sk);
2165 
2166 		xs_save_old_callbacks(transport, sk);
2167 
2168 		sk->sk_user_data = xprt;
2169 		sk->sk_data_ready = xs_data_ready;
2170 		sk->sk_write_space = xs_udp_write_space;
2171 		sk->sk_use_task_frag = false;
2172 
2173 		xprt_set_connected(xprt);
2174 
2175 		/* Reset to new socket */
2176 		transport->sock = sock;
2177 		transport->inet = sk;
2178 
2179 		xs_set_memalloc(xprt);
2180 
2181 		release_sock(sk);
2182 	}
2183 	xs_udp_do_set_buffer_size(xprt);
2184 
2185 	xprt->stat.connect_start = jiffies;
2186 }
2187 
2188 static void xs_udp_setup_socket(struct work_struct *work)
2189 {
2190 	struct sock_xprt *transport =
2191 		container_of(work, struct sock_xprt, connect_worker.work);
2192 	struct rpc_xprt *xprt = &transport->xprt;
2193 	struct socket *sock;
2194 	int status = -EIO;
2195 	unsigned int pflags = current->flags;
2196 
2197 	if (atomic_read(&xprt->swapper))
2198 		current->flags |= PF_MEMALLOC;
2199 	sock = xs_create_sock(xprt, transport,
2200 			xs_addr(xprt)->sa_family, SOCK_DGRAM,
2201 			IPPROTO_UDP, false);
2202 	if (IS_ERR(sock))
2203 		goto out;
2204 
2205 	dprintk("RPC:       worker connecting xprt %p via %s to "
2206 				"%s (port %s)\n", xprt,
2207 			xprt->address_strings[RPC_DISPLAY_PROTO],
2208 			xprt->address_strings[RPC_DISPLAY_ADDR],
2209 			xprt->address_strings[RPC_DISPLAY_PORT]);
2210 
2211 	xs_udp_finish_connecting(xprt, sock);
2212 	trace_rpc_socket_connect(xprt, sock, 0);
2213 	status = 0;
2214 out:
2215 	xprt_clear_connecting(xprt);
2216 	xprt_unlock_connect(xprt, transport);
2217 	xprt_wake_pending_tasks(xprt, status);
2218 	current_restore_flags(pflags, PF_MEMALLOC);
2219 }
2220 
2221 /**
2222  * xs_tcp_shutdown - gracefully shut down a TCP socket
2223  * @xprt: transport
2224  *
2225  * Initiates a graceful shutdown of the TCP socket by calling the
2226  * equivalent of shutdown(SHUT_RDWR);
2227  */
2228 static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2229 {
2230 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2231 	struct socket *sock = transport->sock;
2232 	int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
2233 
2234 	if (sock == NULL)
2235 		return;
2236 	if (!xprt->reuseport) {
2237 		xs_close(xprt);
2238 		return;
2239 	}
2240 	switch (skst) {
2241 	case TCP_FIN_WAIT1:
2242 	case TCP_FIN_WAIT2:
2243 	case TCP_LAST_ACK:
2244 		break;
2245 	case TCP_ESTABLISHED:
2246 	case TCP_CLOSE_WAIT:
2247 		kernel_sock_shutdown(sock, SHUT_RDWR);
2248 		trace_rpc_socket_shutdown(xprt, sock);
2249 		break;
2250 	default:
2251 		xs_reset_transport(transport);
2252 	}
2253 }
2254 
2255 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
2256 		struct socket *sock)
2257 {
2258 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2259 	struct net *net = sock_net(sock->sk);
2260 	unsigned long connect_timeout;
2261 	unsigned long syn_retries;
2262 	unsigned int keepidle;
2263 	unsigned int keepcnt;
2264 	unsigned int timeo;
2265 	unsigned long t;
2266 
2267 	spin_lock(&xprt->transport_lock);
2268 	keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
2269 	keepcnt = xprt->timeout->to_retries + 1;
2270 	timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2271 		(xprt->timeout->to_retries + 1);
2272 	clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2273 	spin_unlock(&xprt->transport_lock);
2274 
2275 	/* TCP Keepalive options */
2276 	sock_set_keepalive(sock->sk);
2277 	tcp_sock_set_keepidle(sock->sk, keepidle);
2278 	tcp_sock_set_keepintvl(sock->sk, keepidle);
2279 	tcp_sock_set_keepcnt(sock->sk, keepcnt);
2280 
2281 	/* TCP user timeout (see RFC5482) */
2282 	tcp_sock_set_user_timeout(sock->sk, timeo);
2283 
2284 	/* Connect timeout */
2285 	connect_timeout = max_t(unsigned long,
2286 				DIV_ROUND_UP(xprt->connect_timeout, HZ), 1);
2287 	syn_retries = max_t(unsigned long,
2288 			    READ_ONCE(net->ipv4.sysctl_tcp_syn_retries), 1);
2289 	for (t = 0; t <= syn_retries && (1UL << t) < connect_timeout; t++)
2290 		;
2291 	if (t <= syn_retries)
2292 		tcp_sock_set_syncnt(sock->sk, t - 1);
2293 }
2294 
2295 static void xs_tcp_do_set_connect_timeout(struct rpc_xprt *xprt,
2296 					  unsigned long connect_timeout)
2297 {
2298 	struct sock_xprt *transport =
2299 		container_of(xprt, struct sock_xprt, xprt);
2300 	struct rpc_timeout to;
2301 	unsigned long initval;
2302 
2303 	memcpy(&to, xprt->timeout, sizeof(to));
2304 	/* Arbitrary lower limit */
2305 	initval = max_t(unsigned long, connect_timeout, XS_TCP_INIT_REEST_TO);
2306 	to.to_initval = initval;
2307 	to.to_maxval = initval;
2308 	to.to_retries = 0;
2309 	memcpy(&transport->tcp_timeout, &to, sizeof(transport->tcp_timeout));
2310 	xprt->timeout = &transport->tcp_timeout;
2311 	xprt->connect_timeout = connect_timeout;
2312 }
2313 
2314 static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
2315 		unsigned long connect_timeout,
2316 		unsigned long reconnect_timeout)
2317 {
2318 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2319 
2320 	spin_lock(&xprt->transport_lock);
2321 	if (reconnect_timeout < xprt->max_reconnect_timeout)
2322 		xprt->max_reconnect_timeout = reconnect_timeout;
2323 	if (connect_timeout < xprt->connect_timeout)
2324 		xs_tcp_do_set_connect_timeout(xprt, connect_timeout);
2325 	set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2326 	spin_unlock(&xprt->transport_lock);
2327 }
2328 
2329 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2330 {
2331 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2332 
2333 	if (!transport->inet) {
2334 		struct sock *sk = sock->sk;
2335 
2336 		/* Avoid temporary address, they are bad for long-lived
2337 		 * connections such as NFS mounts.
2338 		 * RFC4941, section 3.6 suggests that:
2339 		 *    Individual applications, which have specific
2340 		 *    knowledge about the normal duration of connections,
2341 		 *    MAY override this as appropriate.
2342 		 */
2343 		if (xs_addr(xprt)->sa_family == PF_INET6) {
2344 			ip6_sock_set_addr_preferences(sk,
2345 				IPV6_PREFER_SRC_PUBLIC);
2346 		}
2347 
2348 		xs_tcp_set_socket_timeouts(xprt, sock);
2349 		tcp_sock_set_nodelay(sk);
2350 
2351 		lock_sock(sk);
2352 
2353 		xs_save_old_callbacks(transport, sk);
2354 
2355 		sk->sk_user_data = xprt;
2356 		sk->sk_data_ready = xs_data_ready;
2357 		sk->sk_state_change = xs_tcp_state_change;
2358 		sk->sk_write_space = xs_tcp_write_space;
2359 		sk->sk_error_report = xs_error_report;
2360 		sk->sk_use_task_frag = false;
2361 
2362 		/* socket options */
2363 		sock_reset_flag(sk, SOCK_LINGER);
2364 
2365 		xprt_clear_connected(xprt);
2366 
2367 		/* Reset to new socket */
2368 		transport->sock = sock;
2369 		transport->inet = sk;
2370 
2371 		release_sock(sk);
2372 	}
2373 
2374 	if (!xprt_bound(xprt))
2375 		return -ENOTCONN;
2376 
2377 	xs_set_memalloc(xprt);
2378 
2379 	xs_stream_start_connect(transport);
2380 
2381 	/* Tell the socket layer to start connecting... */
2382 	set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2383 	return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2384 }
2385 
2386 /**
2387  * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2388  * @work: queued work item
2389  *
2390  * Invoked by a work queue tasklet.
2391  */
2392 static void xs_tcp_setup_socket(struct work_struct *work)
2393 {
2394 	struct sock_xprt *transport =
2395 		container_of(work, struct sock_xprt, connect_worker.work);
2396 	struct socket *sock = transport->sock;
2397 	struct rpc_xprt *xprt = &transport->xprt;
2398 	int status;
2399 	unsigned int pflags = current->flags;
2400 
2401 	if (atomic_read(&xprt->swapper))
2402 		current->flags |= PF_MEMALLOC;
2403 
2404 	if (xprt_connected(xprt))
2405 		goto out;
2406 	if (test_and_clear_bit(XPRT_SOCK_CONNECT_SENT,
2407 			       &transport->sock_state) ||
2408 	    !sock) {
2409 		xs_reset_transport(transport);
2410 		sock = xs_create_sock(xprt, transport, xs_addr(xprt)->sa_family,
2411 				      SOCK_STREAM, IPPROTO_TCP, true);
2412 		if (IS_ERR(sock)) {
2413 			xprt_wake_pending_tasks(xprt, PTR_ERR(sock));
2414 			goto out;
2415 		}
2416 	}
2417 
2418 	dprintk("RPC:       worker connecting xprt %p via %s to "
2419 				"%s (port %s)\n", xprt,
2420 			xprt->address_strings[RPC_DISPLAY_PROTO],
2421 			xprt->address_strings[RPC_DISPLAY_ADDR],
2422 			xprt->address_strings[RPC_DISPLAY_PORT]);
2423 
2424 	status = xs_tcp_finish_connecting(xprt, sock);
2425 	trace_rpc_socket_connect(xprt, sock, status);
2426 	dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2427 			xprt, -status, xprt_connected(xprt),
2428 			sock->sk->sk_state);
2429 	switch (status) {
2430 	case 0:
2431 	case -EINPROGRESS:
2432 		/* SYN_SENT! */
2433 		set_bit(XPRT_SOCK_CONNECT_SENT, &transport->sock_state);
2434 		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2435 			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2436 		fallthrough;
2437 	case -EALREADY:
2438 		goto out_unlock;
2439 	case -EADDRNOTAVAIL:
2440 		/* Source port number is unavailable. Try a new one! */
2441 		transport->srcport = 0;
2442 		status = -EAGAIN;
2443 		break;
2444 	case -EPERM:
2445 		/* Happens, for instance, if a BPF program is preventing
2446 		 * the connect. Remap the error so upper layers can better
2447 		 * deal with it.
2448 		 */
2449 		status = -ECONNREFUSED;
2450 		fallthrough;
2451 	case -EINVAL:
2452 		/* Happens, for instance, if the user specified a link
2453 		 * local IPv6 address without a scope-id.
2454 		 */
2455 	case -ECONNREFUSED:
2456 	case -ECONNRESET:
2457 	case -ENETDOWN:
2458 	case -ENETUNREACH:
2459 	case -EHOSTUNREACH:
2460 	case -EADDRINUSE:
2461 	case -ENOBUFS:
2462 		break;
2463 	default:
2464 		printk("%s: connect returned unhandled error %d\n",
2465 			__func__, status);
2466 		status = -EAGAIN;
2467 	}
2468 
2469 	/* xs_tcp_force_close() wakes tasks with a fixed error code.
2470 	 * We need to wake them first to ensure the correct error code.
2471 	 */
2472 	xprt_wake_pending_tasks(xprt, status);
2473 	xs_tcp_force_close(xprt);
2474 out:
2475 	xprt_clear_connecting(xprt);
2476 out_unlock:
2477 	xprt_unlock_connect(xprt, transport);
2478 	current_restore_flags(pflags, PF_MEMALLOC);
2479 }
2480 
2481 /*
2482  * Transfer the connected socket to @upper_transport, then mark that
2483  * xprt CONNECTED.
2484  */
2485 static int xs_tcp_tls_finish_connecting(struct rpc_xprt *lower_xprt,
2486 					struct sock_xprt *upper_transport)
2487 {
2488 	struct sock_xprt *lower_transport =
2489 			container_of(lower_xprt, struct sock_xprt, xprt);
2490 	struct rpc_xprt *upper_xprt = &upper_transport->xprt;
2491 
2492 	if (!upper_transport->inet) {
2493 		struct socket *sock = lower_transport->sock;
2494 		struct sock *sk = sock->sk;
2495 
2496 		/* Avoid temporary address, they are bad for long-lived
2497 		 * connections such as NFS mounts.
2498 		 * RFC4941, section 3.6 suggests that:
2499 		 *    Individual applications, which have specific
2500 		 *    knowledge about the normal duration of connections,
2501 		 *    MAY override this as appropriate.
2502 		 */
2503 		if (xs_addr(upper_xprt)->sa_family == PF_INET6)
2504 			ip6_sock_set_addr_preferences(sk, IPV6_PREFER_SRC_PUBLIC);
2505 
2506 		xs_tcp_set_socket_timeouts(upper_xprt, sock);
2507 		tcp_sock_set_nodelay(sk);
2508 
2509 		lock_sock(sk);
2510 
2511 		/* @sk is already connected, so it now has the RPC callbacks.
2512 		 * Reach into @lower_transport to save the original ones.
2513 		 */
2514 		upper_transport->old_data_ready = lower_transport->old_data_ready;
2515 		upper_transport->old_state_change = lower_transport->old_state_change;
2516 		upper_transport->old_write_space = lower_transport->old_write_space;
2517 		upper_transport->old_error_report = lower_transport->old_error_report;
2518 		sk->sk_user_data = upper_xprt;
2519 
2520 		/* socket options */
2521 		sock_reset_flag(sk, SOCK_LINGER);
2522 
2523 		xprt_clear_connected(upper_xprt);
2524 
2525 		upper_transport->sock = sock;
2526 		upper_transport->inet = sk;
2527 		upper_transport->file = lower_transport->file;
2528 
2529 		release_sock(sk);
2530 
2531 		/* Reset lower_transport before shutting down its clnt */
2532 		mutex_lock(&lower_transport->recv_mutex);
2533 		lower_transport->inet = NULL;
2534 		lower_transport->sock = NULL;
2535 		lower_transport->file = NULL;
2536 
2537 		xprt_clear_connected(lower_xprt);
2538 		xs_sock_reset_connection_flags(lower_xprt);
2539 		xs_stream_reset_connect(lower_transport);
2540 		mutex_unlock(&lower_transport->recv_mutex);
2541 	}
2542 
2543 	if (!xprt_bound(upper_xprt))
2544 		return -ENOTCONN;
2545 
2546 	xs_set_memalloc(upper_xprt);
2547 
2548 	if (!xprt_test_and_set_connected(upper_xprt)) {
2549 		upper_xprt->connect_cookie++;
2550 		clear_bit(XPRT_SOCK_CONNECTING, &upper_transport->sock_state);
2551 		xprt_clear_connecting(upper_xprt);
2552 
2553 		upper_xprt->stat.connect_count++;
2554 		upper_xprt->stat.connect_time += (long)jiffies -
2555 					   upper_xprt->stat.connect_start;
2556 		xs_run_error_worker(upper_transport, XPRT_SOCK_WAKE_PENDING);
2557 	}
2558 	return 0;
2559 }
2560 
2561 /**
2562  * xs_tls_handshake_done - TLS handshake completion handler
2563  * @data: address of xprt to wake
2564  * @status: status of handshake
2565  * @peerid: serial number of key containing the remote's identity
2566  *
2567  */
2568 static void xs_tls_handshake_done(void *data, int status, key_serial_t peerid)
2569 {
2570 	struct rpc_xprt *lower_xprt = data;
2571 	struct sock_xprt *lower_transport =
2572 				container_of(lower_xprt, struct sock_xprt, xprt);
2573 
2574 	lower_transport->xprt_err = status ? -EACCES : 0;
2575 	complete(&lower_transport->handshake_done);
2576 	xprt_put(lower_xprt);
2577 }
2578 
2579 static int xs_tls_handshake_sync(struct rpc_xprt *lower_xprt, struct xprtsec_parms *xprtsec)
2580 {
2581 	struct sock_xprt *lower_transport =
2582 				container_of(lower_xprt, struct sock_xprt, xprt);
2583 	struct tls_handshake_args args = {
2584 		.ta_sock	= lower_transport->sock,
2585 		.ta_done	= xs_tls_handshake_done,
2586 		.ta_data	= xprt_get(lower_xprt),
2587 		.ta_peername	= lower_xprt->servername,
2588 	};
2589 	struct sock *sk = lower_transport->inet;
2590 	int rc;
2591 
2592 	init_completion(&lower_transport->handshake_done);
2593 	set_bit(XPRT_SOCK_IGNORE_RECV, &lower_transport->sock_state);
2594 	lower_transport->xprt_err = -ETIMEDOUT;
2595 	switch (xprtsec->policy) {
2596 	case RPC_XPRTSEC_TLS_ANON:
2597 		rc = tls_client_hello_anon(&args, GFP_KERNEL);
2598 		if (rc)
2599 			goto out_put_xprt;
2600 		break;
2601 	case RPC_XPRTSEC_TLS_X509:
2602 		args.ta_my_cert = xprtsec->cert_serial;
2603 		args.ta_my_privkey = xprtsec->privkey_serial;
2604 		rc = tls_client_hello_x509(&args, GFP_KERNEL);
2605 		if (rc)
2606 			goto out_put_xprt;
2607 		break;
2608 	default:
2609 		rc = -EACCES;
2610 		goto out_put_xprt;
2611 	}
2612 
2613 	rc = wait_for_completion_interruptible_timeout(&lower_transport->handshake_done,
2614 						       XS_TLS_HANDSHAKE_TO);
2615 	if (rc <= 0) {
2616 		if (!tls_handshake_cancel(sk)) {
2617 			if (rc == 0)
2618 				rc = -ETIMEDOUT;
2619 			goto out_put_xprt;
2620 		}
2621 	}
2622 
2623 	rc = lower_transport->xprt_err;
2624 
2625 out:
2626 	xs_stream_reset_connect(lower_transport);
2627 	clear_bit(XPRT_SOCK_IGNORE_RECV, &lower_transport->sock_state);
2628 	return rc;
2629 
2630 out_put_xprt:
2631 	xprt_put(lower_xprt);
2632 	goto out;
2633 }
2634 
2635 /**
2636  * xs_tcp_tls_setup_socket - establish a TLS session on a TCP socket
2637  * @work: queued work item
2638  *
2639  * Invoked by a work queue tasklet.
2640  *
2641  * For RPC-with-TLS, there is a two-stage connection process.
2642  *
2643  * The "upper-layer xprt" is visible to the RPC consumer. Once it has
2644  * been marked connected, the consumer knows that a TCP connection and
2645  * a TLS session have been established.
2646  *
2647  * A "lower-layer xprt", created in this function, handles the mechanics
2648  * of connecting the TCP socket, performing the RPC_AUTH_TLS probe, and
2649  * then driving the TLS handshake. Once all that is complete, the upper
2650  * layer xprt is marked connected.
2651  */
2652 static void xs_tcp_tls_setup_socket(struct work_struct *work)
2653 {
2654 	struct sock_xprt *upper_transport =
2655 		container_of(work, struct sock_xprt, connect_worker.work);
2656 	struct rpc_clnt *upper_clnt = upper_transport->clnt;
2657 	struct rpc_xprt *upper_xprt = &upper_transport->xprt;
2658 	struct rpc_create_args args = {
2659 		.net		= upper_xprt->xprt_net,
2660 		.protocol	= upper_xprt->prot,
2661 		.address	= (struct sockaddr *)&upper_xprt->addr,
2662 		.addrsize	= upper_xprt->addrlen,
2663 		.timeout	= upper_clnt->cl_timeout,
2664 		.servername	= upper_xprt->servername,
2665 		.program	= upper_clnt->cl_program,
2666 		.prognumber	= upper_clnt->cl_prog,
2667 		.version	= upper_clnt->cl_vers,
2668 		.authflavor	= RPC_AUTH_TLS,
2669 		.cred		= upper_clnt->cl_cred,
2670 		.xprtsec	= {
2671 			.policy		= RPC_XPRTSEC_NONE,
2672 		},
2673 		.stats		= upper_clnt->cl_stats,
2674 	};
2675 	unsigned int pflags = current->flags;
2676 	struct rpc_clnt *lower_clnt;
2677 	struct rpc_xprt *lower_xprt;
2678 	int status;
2679 
2680 	if (atomic_read(&upper_xprt->swapper))
2681 		current->flags |= PF_MEMALLOC;
2682 
2683 	xs_stream_start_connect(upper_transport);
2684 
2685 	/* This implicitly sends an RPC_AUTH_TLS probe */
2686 	lower_clnt = rpc_create(&args);
2687 	if (IS_ERR(lower_clnt)) {
2688 		trace_rpc_tls_unavailable(upper_clnt, upper_xprt);
2689 		clear_bit(XPRT_SOCK_CONNECTING, &upper_transport->sock_state);
2690 		xprt_clear_connecting(upper_xprt);
2691 		xprt_wake_pending_tasks(upper_xprt, PTR_ERR(lower_clnt));
2692 		xs_run_error_worker(upper_transport, XPRT_SOCK_WAKE_PENDING);
2693 		goto out_unlock;
2694 	}
2695 
2696 	/* RPC_AUTH_TLS probe was successful. Try a TLS handshake on
2697 	 * the lower xprt.
2698 	 */
2699 	rcu_read_lock();
2700 	lower_xprt = rcu_dereference(lower_clnt->cl_xprt);
2701 	rcu_read_unlock();
2702 
2703 	if (wait_on_bit_lock(&lower_xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2704 		goto out_unlock;
2705 
2706 	status = xs_tls_handshake_sync(lower_xprt, &upper_xprt->xprtsec);
2707 	if (status) {
2708 		trace_rpc_tls_not_started(upper_clnt, upper_xprt);
2709 		goto out_close;
2710 	}
2711 
2712 	status = xs_tcp_tls_finish_connecting(lower_xprt, upper_transport);
2713 	if (status)
2714 		goto out_close;
2715 	xprt_release_write(lower_xprt, NULL);
2716 
2717 	trace_rpc_socket_connect(upper_xprt, upper_transport->sock, 0);
2718 	if (!xprt_test_and_set_connected(upper_xprt)) {
2719 		upper_xprt->connect_cookie++;
2720 		clear_bit(XPRT_SOCK_CONNECTING, &upper_transport->sock_state);
2721 		xprt_clear_connecting(upper_xprt);
2722 
2723 		upper_xprt->stat.connect_count++;
2724 		upper_xprt->stat.connect_time += (long)jiffies -
2725 					   upper_xprt->stat.connect_start;
2726 		xs_run_error_worker(upper_transport, XPRT_SOCK_WAKE_PENDING);
2727 	}
2728 	rpc_shutdown_client(lower_clnt);
2729 
2730 out_unlock:
2731 	current_restore_flags(pflags, PF_MEMALLOC);
2732 	upper_transport->clnt = NULL;
2733 	xprt_unlock_connect(upper_xprt, upper_transport);
2734 	return;
2735 
2736 out_close:
2737 	xprt_release_write(lower_xprt, NULL);
2738 	rpc_shutdown_client(lower_clnt);
2739 
2740 	/* xprt_force_disconnect() wakes tasks with a fixed tk_status code.
2741 	 * Wake them first here to ensure they get our tk_status code.
2742 	 */
2743 	xprt_wake_pending_tasks(upper_xprt, status);
2744 	xs_tcp_force_close(upper_xprt);
2745 	xprt_clear_connecting(upper_xprt);
2746 	goto out_unlock;
2747 }
2748 
2749 /**
2750  * xs_connect - connect a socket to a remote endpoint
2751  * @xprt: pointer to transport structure
2752  * @task: address of RPC task that manages state of connect request
2753  *
2754  * TCP: If the remote end dropped the connection, delay reconnecting.
2755  *
2756  * UDP socket connects are synchronous, but we use a work queue anyway
2757  * to guarantee that even unprivileged user processes can set up a
2758  * socket on a privileged port.
2759  *
2760  * If a UDP socket connect fails, the delay behavior here prevents
2761  * retry floods (hard mounts).
2762  */
2763 static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2764 {
2765 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2766 	unsigned long delay = 0;
2767 
2768 	WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2769 
2770 	if (transport->sock != NULL) {
2771 		dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2772 			"seconds\n", xprt, xprt->reestablish_timeout / HZ);
2773 
2774 		delay = xprt_reconnect_delay(xprt);
2775 		xprt_reconnect_backoff(xprt, XS_TCP_INIT_REEST_TO);
2776 
2777 	} else
2778 		dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2779 
2780 	transport->clnt = task->tk_client;
2781 	queue_delayed_work(xprtiod_workqueue,
2782 			&transport->connect_worker,
2783 			delay);
2784 }
2785 
2786 static void xs_wake_disconnect(struct sock_xprt *transport)
2787 {
2788 	if (test_and_clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state))
2789 		xs_tcp_force_close(&transport->xprt);
2790 }
2791 
2792 static void xs_wake_write(struct sock_xprt *transport)
2793 {
2794 	if (test_and_clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state))
2795 		xprt_write_space(&transport->xprt);
2796 }
2797 
2798 static void xs_wake_error(struct sock_xprt *transport)
2799 {
2800 	int sockerr;
2801 
2802 	if (!test_and_clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2803 		return;
2804 	sockerr = xchg(&transport->xprt_err, 0);
2805 	if (sockerr < 0) {
2806 		xprt_wake_pending_tasks(&transport->xprt, sockerr);
2807 		xs_tcp_force_close(&transport->xprt);
2808 	}
2809 }
2810 
2811 static void xs_wake_pending(struct sock_xprt *transport)
2812 {
2813 	if (test_and_clear_bit(XPRT_SOCK_WAKE_PENDING, &transport->sock_state))
2814 		xprt_wake_pending_tasks(&transport->xprt, -EAGAIN);
2815 }
2816 
2817 static void xs_error_handle(struct work_struct *work)
2818 {
2819 	struct sock_xprt *transport = container_of(work,
2820 			struct sock_xprt, error_worker);
2821 
2822 	xs_wake_disconnect(transport);
2823 	xs_wake_write(transport);
2824 	xs_wake_error(transport);
2825 	xs_wake_pending(transport);
2826 }
2827 
2828 /**
2829  * xs_local_print_stats - display AF_LOCAL socket-specific stats
2830  * @xprt: rpc_xprt struct containing statistics
2831  * @seq: output file
2832  *
2833  */
2834 static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2835 {
2836 	long idle_time = 0;
2837 
2838 	if (xprt_connected(xprt))
2839 		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2840 
2841 	seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2842 			"%llu %llu %lu %llu %llu\n",
2843 			xprt->stat.bind_count,
2844 			xprt->stat.connect_count,
2845 			xprt->stat.connect_time / HZ,
2846 			idle_time,
2847 			xprt->stat.sends,
2848 			xprt->stat.recvs,
2849 			xprt->stat.bad_xids,
2850 			xprt->stat.req_u,
2851 			xprt->stat.bklog_u,
2852 			xprt->stat.max_slots,
2853 			xprt->stat.sending_u,
2854 			xprt->stat.pending_u);
2855 }
2856 
2857 /**
2858  * xs_udp_print_stats - display UDP socket-specific stats
2859  * @xprt: rpc_xprt struct containing statistics
2860  * @seq: output file
2861  *
2862  */
2863 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2864 {
2865 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2866 
2867 	seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2868 			"%lu %llu %llu\n",
2869 			transport->srcport,
2870 			xprt->stat.bind_count,
2871 			xprt->stat.sends,
2872 			xprt->stat.recvs,
2873 			xprt->stat.bad_xids,
2874 			xprt->stat.req_u,
2875 			xprt->stat.bklog_u,
2876 			xprt->stat.max_slots,
2877 			xprt->stat.sending_u,
2878 			xprt->stat.pending_u);
2879 }
2880 
2881 /**
2882  * xs_tcp_print_stats - display TCP socket-specific stats
2883  * @xprt: rpc_xprt struct containing statistics
2884  * @seq: output file
2885  *
2886  */
2887 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2888 {
2889 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2890 	long idle_time = 0;
2891 
2892 	if (xprt_connected(xprt))
2893 		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2894 
2895 	seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2896 			"%llu %llu %lu %llu %llu\n",
2897 			transport->srcport,
2898 			xprt->stat.bind_count,
2899 			xprt->stat.connect_count,
2900 			xprt->stat.connect_time / HZ,
2901 			idle_time,
2902 			xprt->stat.sends,
2903 			xprt->stat.recvs,
2904 			xprt->stat.bad_xids,
2905 			xprt->stat.req_u,
2906 			xprt->stat.bklog_u,
2907 			xprt->stat.max_slots,
2908 			xprt->stat.sending_u,
2909 			xprt->stat.pending_u);
2910 }
2911 
2912 /*
2913  * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2914  * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2915  * to use the server side send routines.
2916  */
2917 static int bc_malloc(struct rpc_task *task)
2918 {
2919 	struct rpc_rqst *rqst = task->tk_rqstp;
2920 	size_t size = rqst->rq_callsize;
2921 	struct page *page;
2922 	struct rpc_buffer *buf;
2923 
2924 	if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2925 		WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2926 			  size);
2927 		return -EINVAL;
2928 	}
2929 
2930 	page = alloc_page(GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
2931 	if (!page)
2932 		return -ENOMEM;
2933 
2934 	buf = page_address(page);
2935 	buf->len = PAGE_SIZE;
2936 
2937 	rqst->rq_buffer = buf->data;
2938 	rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2939 	return 0;
2940 }
2941 
2942 /*
2943  * Free the space allocated in the bc_alloc routine
2944  */
2945 static void bc_free(struct rpc_task *task)
2946 {
2947 	void *buffer = task->tk_rqstp->rq_buffer;
2948 	struct rpc_buffer *buf;
2949 
2950 	buf = container_of(buffer, struct rpc_buffer, data);
2951 	free_page((unsigned long)buf);
2952 }
2953 
2954 static int bc_sendto(struct rpc_rqst *req)
2955 {
2956 	struct xdr_buf *xdr = &req->rq_snd_buf;
2957 	struct sock_xprt *transport =
2958 			container_of(req->rq_xprt, struct sock_xprt, xprt);
2959 	struct msghdr msg = {
2960 		.msg_flags	= 0,
2961 	};
2962 	rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT |
2963 					 (u32)xdr->len);
2964 	unsigned int sent = 0;
2965 	int err;
2966 
2967 	req->rq_xtime = ktime_get();
2968 	err = xdr_alloc_bvec(xdr, rpc_task_gfp_mask());
2969 	if (err < 0)
2970 		return err;
2971 	err = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, marker, &sent);
2972 	xdr_free_bvec(xdr);
2973 	if (err < 0 || sent != (xdr->len + sizeof(marker)))
2974 		return -EAGAIN;
2975 	return sent;
2976 }
2977 
2978 /**
2979  * bc_send_request - Send a backchannel Call on a TCP socket
2980  * @req: rpc_rqst containing Call message to be sent
2981  *
2982  * xpt_mutex ensures @rqstp's whole message is written to the socket
2983  * without interruption.
2984  *
2985  * Return values:
2986  *   %0 if the message was sent successfully
2987  *   %ENOTCONN if the message was not sent
2988  */
2989 static int bc_send_request(struct rpc_rqst *req)
2990 {
2991 	struct svc_xprt	*xprt;
2992 	int len;
2993 
2994 	/*
2995 	 * Get the server socket associated with this callback xprt
2996 	 */
2997 	xprt = req->rq_xprt->bc_xprt;
2998 
2999 	/*
3000 	 * Grab the mutex to serialize data as the connection is shared
3001 	 * with the fore channel
3002 	 */
3003 	mutex_lock(&xprt->xpt_mutex);
3004 	if (test_bit(XPT_DEAD, &xprt->xpt_flags))
3005 		len = -ENOTCONN;
3006 	else
3007 		len = bc_sendto(req);
3008 	mutex_unlock(&xprt->xpt_mutex);
3009 
3010 	if (len > 0)
3011 		len = 0;
3012 
3013 	return len;
3014 }
3015 
3016 static void bc_close(struct rpc_xprt *xprt)
3017 {
3018 	xprt_disconnect_done(xprt);
3019 }
3020 
3021 static void bc_destroy(struct rpc_xprt *xprt)
3022 {
3023 	dprintk("RPC:       bc_destroy xprt %p\n", xprt);
3024 
3025 	xs_xprt_free(xprt);
3026 	module_put(THIS_MODULE);
3027 }
3028 
3029 static const struct rpc_xprt_ops xs_local_ops = {
3030 	.reserve_xprt		= xprt_reserve_xprt,
3031 	.release_xprt		= xprt_release_xprt,
3032 	.alloc_slot		= xprt_alloc_slot,
3033 	.free_slot		= xprt_free_slot,
3034 	.rpcbind		= xs_local_rpcbind,
3035 	.set_port		= xs_local_set_port,
3036 	.connect		= xs_local_connect,
3037 	.buf_alloc		= rpc_malloc,
3038 	.buf_free		= rpc_free,
3039 	.prepare_request	= xs_stream_prepare_request,
3040 	.send_request		= xs_local_send_request,
3041 	.abort_send_request	= xs_stream_abort_send_request,
3042 	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
3043 	.close			= xs_close,
3044 	.destroy		= xs_destroy,
3045 	.print_stats		= xs_local_print_stats,
3046 	.enable_swap		= xs_enable_swap,
3047 	.disable_swap		= xs_disable_swap,
3048 };
3049 
3050 static const struct rpc_xprt_ops xs_udp_ops = {
3051 	.set_buffer_size	= xs_udp_set_buffer_size,
3052 	.reserve_xprt		= xprt_reserve_xprt_cong,
3053 	.release_xprt		= xprt_release_xprt_cong,
3054 	.alloc_slot		= xprt_alloc_slot,
3055 	.free_slot		= xprt_free_slot,
3056 	.rpcbind		= rpcb_getport_async,
3057 	.set_port		= xs_set_port,
3058 	.connect		= xs_connect,
3059 	.get_srcaddr		= xs_sock_srcaddr,
3060 	.get_srcport		= xs_sock_srcport,
3061 	.buf_alloc		= rpc_malloc,
3062 	.buf_free		= rpc_free,
3063 	.send_request		= xs_udp_send_request,
3064 	.wait_for_reply_request	= xprt_wait_for_reply_request_rtt,
3065 	.timer			= xs_udp_timer,
3066 	.release_request	= xprt_release_rqst_cong,
3067 	.close			= xs_close,
3068 	.destroy		= xs_destroy,
3069 	.print_stats		= xs_udp_print_stats,
3070 	.enable_swap		= xs_enable_swap,
3071 	.disable_swap		= xs_disable_swap,
3072 	.inject_disconnect	= xs_inject_disconnect,
3073 };
3074 
3075 static const struct rpc_xprt_ops xs_tcp_ops = {
3076 	.reserve_xprt		= xprt_reserve_xprt,
3077 	.release_xprt		= xprt_release_xprt,
3078 	.alloc_slot		= xprt_alloc_slot,
3079 	.free_slot		= xprt_free_slot,
3080 	.rpcbind		= rpcb_getport_async,
3081 	.set_port		= xs_set_port,
3082 	.connect		= xs_connect,
3083 	.get_srcaddr		= xs_sock_srcaddr,
3084 	.get_srcport		= xs_sock_srcport,
3085 	.buf_alloc		= rpc_malloc,
3086 	.buf_free		= rpc_free,
3087 	.prepare_request	= xs_stream_prepare_request,
3088 	.send_request		= xs_tcp_send_request,
3089 	.abort_send_request	= xs_stream_abort_send_request,
3090 	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
3091 	.close			= xs_tcp_shutdown,
3092 	.destroy		= xs_destroy,
3093 	.set_connect_timeout	= xs_tcp_set_connect_timeout,
3094 	.print_stats		= xs_tcp_print_stats,
3095 	.enable_swap		= xs_enable_swap,
3096 	.disable_swap		= xs_disable_swap,
3097 	.inject_disconnect	= xs_inject_disconnect,
3098 #ifdef CONFIG_SUNRPC_BACKCHANNEL
3099 	.bc_setup		= xprt_setup_bc,
3100 	.bc_maxpayload		= xs_tcp_bc_maxpayload,
3101 	.bc_num_slots		= xprt_bc_max_slots,
3102 	.bc_free_rqst		= xprt_free_bc_rqst,
3103 	.bc_destroy		= xprt_destroy_bc,
3104 #endif
3105 };
3106 
3107 /*
3108  * The rpc_xprt_ops for the server backchannel
3109  */
3110 
3111 static const struct rpc_xprt_ops bc_tcp_ops = {
3112 	.reserve_xprt		= xprt_reserve_xprt,
3113 	.release_xprt		= xprt_release_xprt,
3114 	.alloc_slot		= xprt_alloc_slot,
3115 	.free_slot		= xprt_free_slot,
3116 	.buf_alloc		= bc_malloc,
3117 	.buf_free		= bc_free,
3118 	.send_request		= bc_send_request,
3119 	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
3120 	.close			= bc_close,
3121 	.destroy		= bc_destroy,
3122 	.print_stats		= xs_tcp_print_stats,
3123 	.enable_swap		= xs_enable_swap,
3124 	.disable_swap		= xs_disable_swap,
3125 	.inject_disconnect	= xs_inject_disconnect,
3126 };
3127 
3128 static int xs_init_anyaddr(const int family, struct sockaddr *sap)
3129 {
3130 	static const struct sockaddr_in sin = {
3131 		.sin_family		= AF_INET,
3132 		.sin_addr.s_addr	= htonl(INADDR_ANY),
3133 	};
3134 	static const struct sockaddr_in6 sin6 = {
3135 		.sin6_family		= AF_INET6,
3136 		.sin6_addr		= IN6ADDR_ANY_INIT,
3137 	};
3138 
3139 	switch (family) {
3140 	case AF_LOCAL:
3141 		break;
3142 	case AF_INET:
3143 		memcpy(sap, &sin, sizeof(sin));
3144 		break;
3145 	case AF_INET6:
3146 		memcpy(sap, &sin6, sizeof(sin6));
3147 		break;
3148 	default:
3149 		dprintk("RPC:       %s: Bad address family\n", __func__);
3150 		return -EAFNOSUPPORT;
3151 	}
3152 	return 0;
3153 }
3154 
3155 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
3156 				      unsigned int slot_table_size,
3157 				      unsigned int max_slot_table_size)
3158 {
3159 	struct rpc_xprt *xprt;
3160 	struct sock_xprt *new;
3161 
3162 	if (args->addrlen > sizeof(xprt->addr)) {
3163 		dprintk("RPC:       xs_setup_xprt: address too large\n");
3164 		return ERR_PTR(-EBADF);
3165 	}
3166 
3167 	xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
3168 			max_slot_table_size);
3169 	if (xprt == NULL) {
3170 		dprintk("RPC:       xs_setup_xprt: couldn't allocate "
3171 				"rpc_xprt\n");
3172 		return ERR_PTR(-ENOMEM);
3173 	}
3174 
3175 	new = container_of(xprt, struct sock_xprt, xprt);
3176 	mutex_init(&new->recv_mutex);
3177 	memcpy(&xprt->addr, args->dstaddr, args->addrlen);
3178 	xprt->addrlen = args->addrlen;
3179 	if (args->srcaddr)
3180 		memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
3181 	else {
3182 		int err;
3183 		err = xs_init_anyaddr(args->dstaddr->sa_family,
3184 					(struct sockaddr *)&new->srcaddr);
3185 		if (err != 0) {
3186 			xprt_free(xprt);
3187 			return ERR_PTR(err);
3188 		}
3189 	}
3190 
3191 	return xprt;
3192 }
3193 
3194 static const struct rpc_timeout xs_local_default_timeout = {
3195 	.to_initval = 10 * HZ,
3196 	.to_maxval = 10 * HZ,
3197 	.to_retries = 2,
3198 };
3199 
3200 /**
3201  * xs_setup_local - Set up transport to use an AF_LOCAL socket
3202  * @args: rpc transport creation arguments
3203  *
3204  * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
3205  */
3206 static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
3207 {
3208 	struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
3209 	struct sock_xprt *transport;
3210 	struct rpc_xprt *xprt;
3211 	struct rpc_xprt *ret;
3212 
3213 	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3214 			xprt_max_tcp_slot_table_entries);
3215 	if (IS_ERR(xprt))
3216 		return xprt;
3217 	transport = container_of(xprt, struct sock_xprt, xprt);
3218 
3219 	xprt->prot = 0;
3220 	xprt->xprt_class = &xs_local_transport;
3221 	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3222 
3223 	xprt->bind_timeout = XS_BIND_TO;
3224 	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
3225 	xprt->idle_timeout = XS_IDLE_DISC_TO;
3226 
3227 	xprt->ops = &xs_local_ops;
3228 	xprt->timeout = &xs_local_default_timeout;
3229 
3230 	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
3231 	INIT_WORK(&transport->error_worker, xs_error_handle);
3232 	INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket);
3233 
3234 	switch (sun->sun_family) {
3235 	case AF_LOCAL:
3236 		if (sun->sun_path[0] != '/' && sun->sun_path[0] != '\0') {
3237 			dprintk("RPC:       bad AF_LOCAL address: %s\n",
3238 					sun->sun_path);
3239 			ret = ERR_PTR(-EINVAL);
3240 			goto out_err;
3241 		}
3242 		xprt_set_bound(xprt);
3243 		xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
3244 		break;
3245 	default:
3246 		ret = ERR_PTR(-EAFNOSUPPORT);
3247 		goto out_err;
3248 	}
3249 
3250 	dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
3251 			xprt->address_strings[RPC_DISPLAY_ADDR]);
3252 
3253 	if (try_module_get(THIS_MODULE))
3254 		return xprt;
3255 	ret = ERR_PTR(-EINVAL);
3256 out_err:
3257 	xs_xprt_free(xprt);
3258 	return ret;
3259 }
3260 
3261 static const struct rpc_timeout xs_udp_default_timeout = {
3262 	.to_initval = 5 * HZ,
3263 	.to_maxval = 30 * HZ,
3264 	.to_increment = 5 * HZ,
3265 	.to_retries = 5,
3266 };
3267 
3268 /**
3269  * xs_setup_udp - Set up transport to use a UDP socket
3270  * @args: rpc transport creation arguments
3271  *
3272  */
3273 static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
3274 {
3275 	struct sockaddr *addr = args->dstaddr;
3276 	struct rpc_xprt *xprt;
3277 	struct sock_xprt *transport;
3278 	struct rpc_xprt *ret;
3279 
3280 	xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
3281 			xprt_udp_slot_table_entries);
3282 	if (IS_ERR(xprt))
3283 		return xprt;
3284 	transport = container_of(xprt, struct sock_xprt, xprt);
3285 
3286 	xprt->prot = IPPROTO_UDP;
3287 	xprt->xprt_class = &xs_udp_transport;
3288 	/* XXX: header size can vary due to auth type, IPv6, etc. */
3289 	xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
3290 
3291 	xprt->bind_timeout = XS_BIND_TO;
3292 	xprt->reestablish_timeout = XS_UDP_REEST_TO;
3293 	xprt->idle_timeout = XS_IDLE_DISC_TO;
3294 
3295 	xprt->ops = &xs_udp_ops;
3296 
3297 	xprt->timeout = &xs_udp_default_timeout;
3298 
3299 	INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
3300 	INIT_WORK(&transport->error_worker, xs_error_handle);
3301 	INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
3302 
3303 	switch (addr->sa_family) {
3304 	case AF_INET:
3305 		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3306 			xprt_set_bound(xprt);
3307 
3308 		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
3309 		break;
3310 	case AF_INET6:
3311 		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3312 			xprt_set_bound(xprt);
3313 
3314 		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
3315 		break;
3316 	default:
3317 		ret = ERR_PTR(-EAFNOSUPPORT);
3318 		goto out_err;
3319 	}
3320 
3321 	if (xprt_bound(xprt))
3322 		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3323 				xprt->address_strings[RPC_DISPLAY_ADDR],
3324 				xprt->address_strings[RPC_DISPLAY_PORT],
3325 				xprt->address_strings[RPC_DISPLAY_PROTO]);
3326 	else
3327 		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3328 				xprt->address_strings[RPC_DISPLAY_ADDR],
3329 				xprt->address_strings[RPC_DISPLAY_PROTO]);
3330 
3331 	if (try_module_get(THIS_MODULE))
3332 		return xprt;
3333 	ret = ERR_PTR(-EINVAL);
3334 out_err:
3335 	xs_xprt_free(xprt);
3336 	return ret;
3337 }
3338 
3339 static const struct rpc_timeout xs_tcp_default_timeout = {
3340 	.to_initval = 60 * HZ,
3341 	.to_maxval = 60 * HZ,
3342 	.to_retries = 2,
3343 };
3344 
3345 /**
3346  * xs_setup_tcp - Set up transport to use a TCP socket
3347  * @args: rpc transport creation arguments
3348  *
3349  */
3350 static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
3351 {
3352 	struct sockaddr *addr = args->dstaddr;
3353 	struct rpc_xprt *xprt;
3354 	struct sock_xprt *transport;
3355 	struct rpc_xprt *ret;
3356 	unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
3357 
3358 	if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
3359 		max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
3360 
3361 	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3362 			max_slot_table_size);
3363 	if (IS_ERR(xprt))
3364 		return xprt;
3365 	transport = container_of(xprt, struct sock_xprt, xprt);
3366 
3367 	xprt->prot = IPPROTO_TCP;
3368 	xprt->xprt_class = &xs_tcp_transport;
3369 	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3370 
3371 	xprt->bind_timeout = XS_BIND_TO;
3372 	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
3373 	xprt->idle_timeout = XS_IDLE_DISC_TO;
3374 
3375 	xprt->ops = &xs_tcp_ops;
3376 	xprt->timeout = &xs_tcp_default_timeout;
3377 
3378 	xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
3379 	if (args->reconnect_timeout)
3380 		xprt->max_reconnect_timeout = args->reconnect_timeout;
3381 
3382 	xprt->connect_timeout = xprt->timeout->to_initval *
3383 		(xprt->timeout->to_retries + 1);
3384 	if (args->connect_timeout)
3385 		xs_tcp_do_set_connect_timeout(xprt, args->connect_timeout);
3386 
3387 	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
3388 	INIT_WORK(&transport->error_worker, xs_error_handle);
3389 	INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
3390 
3391 	switch (addr->sa_family) {
3392 	case AF_INET:
3393 		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3394 			xprt_set_bound(xprt);
3395 
3396 		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
3397 		break;
3398 	case AF_INET6:
3399 		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3400 			xprt_set_bound(xprt);
3401 
3402 		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
3403 		break;
3404 	default:
3405 		ret = ERR_PTR(-EAFNOSUPPORT);
3406 		goto out_err;
3407 	}
3408 
3409 	if (xprt_bound(xprt))
3410 		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3411 				xprt->address_strings[RPC_DISPLAY_ADDR],
3412 				xprt->address_strings[RPC_DISPLAY_PORT],
3413 				xprt->address_strings[RPC_DISPLAY_PROTO]);
3414 	else
3415 		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3416 				xprt->address_strings[RPC_DISPLAY_ADDR],
3417 				xprt->address_strings[RPC_DISPLAY_PROTO]);
3418 
3419 	if (try_module_get(THIS_MODULE))
3420 		return xprt;
3421 	ret = ERR_PTR(-EINVAL);
3422 out_err:
3423 	xs_xprt_free(xprt);
3424 	return ret;
3425 }
3426 
3427 /**
3428  * xs_setup_tcp_tls - Set up transport to use a TCP with TLS
3429  * @args: rpc transport creation arguments
3430  *
3431  */
3432 static struct rpc_xprt *xs_setup_tcp_tls(struct xprt_create *args)
3433 {
3434 	struct sockaddr *addr = args->dstaddr;
3435 	struct rpc_xprt *xprt;
3436 	struct sock_xprt *transport;
3437 	struct rpc_xprt *ret;
3438 	unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
3439 
3440 	if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
3441 		max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
3442 
3443 	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3444 			     max_slot_table_size);
3445 	if (IS_ERR(xprt))
3446 		return xprt;
3447 	transport = container_of(xprt, struct sock_xprt, xprt);
3448 
3449 	xprt->prot = IPPROTO_TCP;
3450 	xprt->xprt_class = &xs_tcp_transport;
3451 	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3452 
3453 	xprt->bind_timeout = XS_BIND_TO;
3454 	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
3455 	xprt->idle_timeout = XS_IDLE_DISC_TO;
3456 
3457 	xprt->ops = &xs_tcp_ops;
3458 	xprt->timeout = &xs_tcp_default_timeout;
3459 
3460 	xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
3461 	xprt->connect_timeout = xprt->timeout->to_initval *
3462 		(xprt->timeout->to_retries + 1);
3463 
3464 	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
3465 	INIT_WORK(&transport->error_worker, xs_error_handle);
3466 
3467 	switch (args->xprtsec.policy) {
3468 	case RPC_XPRTSEC_TLS_ANON:
3469 	case RPC_XPRTSEC_TLS_X509:
3470 		xprt->xprtsec = args->xprtsec;
3471 		INIT_DELAYED_WORK(&transport->connect_worker,
3472 				  xs_tcp_tls_setup_socket);
3473 		break;
3474 	default:
3475 		ret = ERR_PTR(-EACCES);
3476 		goto out_err;
3477 	}
3478 
3479 	switch (addr->sa_family) {
3480 	case AF_INET:
3481 		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3482 			xprt_set_bound(xprt);
3483 
3484 		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
3485 		break;
3486 	case AF_INET6:
3487 		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3488 			xprt_set_bound(xprt);
3489 
3490 		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
3491 		break;
3492 	default:
3493 		ret = ERR_PTR(-EAFNOSUPPORT);
3494 		goto out_err;
3495 	}
3496 
3497 	if (xprt_bound(xprt))
3498 		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3499 			xprt->address_strings[RPC_DISPLAY_ADDR],
3500 			xprt->address_strings[RPC_DISPLAY_PORT],
3501 			xprt->address_strings[RPC_DISPLAY_PROTO]);
3502 	else
3503 		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3504 			xprt->address_strings[RPC_DISPLAY_ADDR],
3505 			xprt->address_strings[RPC_DISPLAY_PROTO]);
3506 
3507 	if (try_module_get(THIS_MODULE))
3508 		return xprt;
3509 	ret = ERR_PTR(-EINVAL);
3510 out_err:
3511 	xs_xprt_free(xprt);
3512 	return ret;
3513 }
3514 
3515 /**
3516  * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
3517  * @args: rpc transport creation arguments
3518  *
3519  */
3520 static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
3521 {
3522 	struct sockaddr *addr = args->dstaddr;
3523 	struct rpc_xprt *xprt;
3524 	struct sock_xprt *transport;
3525 	struct svc_sock *bc_sock;
3526 	struct rpc_xprt *ret;
3527 
3528 	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3529 			xprt_tcp_slot_table_entries);
3530 	if (IS_ERR(xprt))
3531 		return xprt;
3532 	transport = container_of(xprt, struct sock_xprt, xprt);
3533 
3534 	xprt->prot = IPPROTO_TCP;
3535 	xprt->xprt_class = &xs_bc_tcp_transport;
3536 	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3537 	xprt->timeout = &xs_tcp_default_timeout;
3538 
3539 	/* backchannel */
3540 	xprt_set_bound(xprt);
3541 	xprt->bind_timeout = 0;
3542 	xprt->reestablish_timeout = 0;
3543 	xprt->idle_timeout = 0;
3544 
3545 	xprt->ops = &bc_tcp_ops;
3546 
3547 	switch (addr->sa_family) {
3548 	case AF_INET:
3549 		xs_format_peer_addresses(xprt, "tcp",
3550 					 RPCBIND_NETID_TCP);
3551 		break;
3552 	case AF_INET6:
3553 		xs_format_peer_addresses(xprt, "tcp",
3554 				   RPCBIND_NETID_TCP6);
3555 		break;
3556 	default:
3557 		ret = ERR_PTR(-EAFNOSUPPORT);
3558 		goto out_err;
3559 	}
3560 
3561 	dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3562 			xprt->address_strings[RPC_DISPLAY_ADDR],
3563 			xprt->address_strings[RPC_DISPLAY_PORT],
3564 			xprt->address_strings[RPC_DISPLAY_PROTO]);
3565 
3566 	/*
3567 	 * Once we've associated a backchannel xprt with a connection,
3568 	 * we want to keep it around as long as the connection lasts,
3569 	 * in case we need to start using it for a backchannel again;
3570 	 * this reference won't be dropped until bc_xprt is destroyed.
3571 	 */
3572 	xprt_get(xprt);
3573 	args->bc_xprt->xpt_bc_xprt = xprt;
3574 	xprt->bc_xprt = args->bc_xprt;
3575 	bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3576 	transport->sock = bc_sock->sk_sock;
3577 	transport->inet = bc_sock->sk_sk;
3578 
3579 	/*
3580 	 * Since we don't want connections for the backchannel, we set
3581 	 * the xprt status to connected
3582 	 */
3583 	xprt_set_connected(xprt);
3584 
3585 	if (try_module_get(THIS_MODULE))
3586 		return xprt;
3587 
3588 	args->bc_xprt->xpt_bc_xprt = NULL;
3589 	args->bc_xprt->xpt_bc_xps = NULL;
3590 	xprt_put(xprt);
3591 	ret = ERR_PTR(-EINVAL);
3592 out_err:
3593 	xs_xprt_free(xprt);
3594 	return ret;
3595 }
3596 
3597 static struct xprt_class	xs_local_transport = {
3598 	.list		= LIST_HEAD_INIT(xs_local_transport.list),
3599 	.name		= "named UNIX socket",
3600 	.owner		= THIS_MODULE,
3601 	.ident		= XPRT_TRANSPORT_LOCAL,
3602 	.setup		= xs_setup_local,
3603 	.netid		= { "" },
3604 };
3605 
3606 static struct xprt_class	xs_udp_transport = {
3607 	.list		= LIST_HEAD_INIT(xs_udp_transport.list),
3608 	.name		= "udp",
3609 	.owner		= THIS_MODULE,
3610 	.ident		= XPRT_TRANSPORT_UDP,
3611 	.setup		= xs_setup_udp,
3612 	.netid		= { "udp", "udp6", "" },
3613 };
3614 
3615 static struct xprt_class	xs_tcp_transport = {
3616 	.list		= LIST_HEAD_INIT(xs_tcp_transport.list),
3617 	.name		= "tcp",
3618 	.owner		= THIS_MODULE,
3619 	.ident		= XPRT_TRANSPORT_TCP,
3620 	.setup		= xs_setup_tcp,
3621 	.netid		= { "tcp", "tcp6", "" },
3622 };
3623 
3624 static struct xprt_class	xs_tcp_tls_transport = {
3625 	.list		= LIST_HEAD_INIT(xs_tcp_tls_transport.list),
3626 	.name		= "tcp-with-tls",
3627 	.owner		= THIS_MODULE,
3628 	.ident		= XPRT_TRANSPORT_TCP_TLS,
3629 	.setup		= xs_setup_tcp_tls,
3630 	.netid		= { "tcp", "tcp6", "" },
3631 };
3632 
3633 static struct xprt_class	xs_bc_tcp_transport = {
3634 	.list		= LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3635 	.name		= "tcp NFSv4.1 backchannel",
3636 	.owner		= THIS_MODULE,
3637 	.ident		= XPRT_TRANSPORT_BC_TCP,
3638 	.setup		= xs_setup_bc_tcp,
3639 	.netid		= { "" },
3640 };
3641 
3642 /**
3643  * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3644  *
3645  */
3646 int init_socket_xprt(void)
3647 {
3648 	if (!sunrpc_table_header)
3649 		sunrpc_table_header = register_sysctl("sunrpc", xs_tunables_table);
3650 
3651 	xprt_register_transport(&xs_local_transport);
3652 	xprt_register_transport(&xs_udp_transport);
3653 	xprt_register_transport(&xs_tcp_transport);
3654 	xprt_register_transport(&xs_tcp_tls_transport);
3655 	xprt_register_transport(&xs_bc_tcp_transport);
3656 
3657 	return 0;
3658 }
3659 
3660 /**
3661  * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3662  *
3663  */
3664 void cleanup_socket_xprt(void)
3665 {
3666 	if (sunrpc_table_header) {
3667 		unregister_sysctl_table(sunrpc_table_header);
3668 		sunrpc_table_header = NULL;
3669 	}
3670 
3671 	xprt_unregister_transport(&xs_local_transport);
3672 	xprt_unregister_transport(&xs_udp_transport);
3673 	xprt_unregister_transport(&xs_tcp_transport);
3674 	xprt_unregister_transport(&xs_tcp_tls_transport);
3675 	xprt_unregister_transport(&xs_bc_tcp_transport);
3676 }
3677 
3678 static int param_set_portnr(const char *val, const struct kernel_param *kp)
3679 {
3680 	return param_set_uint_minmax(val, kp,
3681 			RPC_MIN_RESVPORT,
3682 			RPC_MAX_RESVPORT);
3683 }
3684 
3685 static const struct kernel_param_ops param_ops_portnr = {
3686 	.set = param_set_portnr,
3687 	.get = param_get_uint,
3688 };
3689 
3690 #define param_check_portnr(name, p) \
3691 	__param_check(name, p, unsigned int);
3692 
3693 module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3694 module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3695 
3696 static int param_set_slot_table_size(const char *val,
3697 				     const struct kernel_param *kp)
3698 {
3699 	return param_set_uint_minmax(val, kp,
3700 			RPC_MIN_SLOT_TABLE,
3701 			RPC_MAX_SLOT_TABLE);
3702 }
3703 
3704 static const struct kernel_param_ops param_ops_slot_table_size = {
3705 	.set = param_set_slot_table_size,
3706 	.get = param_get_uint,
3707 };
3708 
3709 #define param_check_slot_table_size(name, p) \
3710 	__param_check(name, p, unsigned int);
3711 
3712 static int param_set_max_slot_table_size(const char *val,
3713 				     const struct kernel_param *kp)
3714 {
3715 	return param_set_uint_minmax(val, kp,
3716 			RPC_MIN_SLOT_TABLE,
3717 			RPC_MAX_SLOT_TABLE_LIMIT);
3718 }
3719 
3720 static const struct kernel_param_ops param_ops_max_slot_table_size = {
3721 	.set = param_set_max_slot_table_size,
3722 	.get = param_get_uint,
3723 };
3724 
3725 #define param_check_max_slot_table_size(name, p) \
3726 	__param_check(name, p, unsigned int);
3727 
3728 module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3729 		   slot_table_size, 0644);
3730 module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3731 		   max_slot_table_size, 0644);
3732 module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3733 		   slot_table_size, 0644);
3734