xref: /linux/net/sunrpc/xprtsock.c (revision 42fda66387daa53538ae13a2c858396aaf037158)
1 /*
2  * linux/net/sunrpc/xprtsock.c
3  *
4  * Client-side transport implementation for sockets.
5  *
6  * TCP callback races fixes (C) 1998 Red Hat Software <alan@redhat.com>
7  * TCP send fixes (C) 1998 Red Hat Software <alan@redhat.com>
8  * TCP NFS related read + write fixes
9  *  (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
10  *
11  * Rewrite of larges part of the code in order to stabilize TCP stuff.
12  * Fix behaviour when socket buffer is full.
13  *  (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no>
14  *
15  * IP socket transport implementation, (C) 2005 Chuck Lever <cel@netapp.com>
16  *
17  * IPv6 support contributed by Gilles Quillard, Bull Open Source, 2005.
18  *   <gilles.quillard@bull.net>
19  */
20 
21 #include <linux/types.h>
22 #include <linux/slab.h>
23 #include <linux/module.h>
24 #include <linux/capability.h>
25 #include <linux/pagemap.h>
26 #include <linux/errno.h>
27 #include <linux/socket.h>
28 #include <linux/in.h>
29 #include <linux/net.h>
30 #include <linux/mm.h>
31 #include <linux/udp.h>
32 #include <linux/tcp.h>
33 #include <linux/sunrpc/clnt.h>
34 #include <linux/sunrpc/sched.h>
35 #include <linux/sunrpc/xprtsock.h>
36 #include <linux/file.h>
37 
38 #include <net/sock.h>
39 #include <net/checksum.h>
40 #include <net/udp.h>
41 #include <net/tcp.h>
42 
43 /*
44  * xprtsock tunables
45  */
46 unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
47 unsigned int xprt_tcp_slot_table_entries = RPC_DEF_SLOT_TABLE;
48 
49 unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
50 unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
51 
52 /*
53  * We can register our own files under /proc/sys/sunrpc by
54  * calling register_sysctl_table() again.  The files in that
55  * directory become the union of all files registered there.
56  *
57  * We simply need to make sure that we don't collide with
58  * someone else's file names!
59  */
60 
61 #ifdef RPC_DEBUG
62 
63 static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
64 static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
65 static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
66 static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
67 
68 static struct ctl_table_header *sunrpc_table_header;
69 
70 /*
71  * FIXME: changing the UDP slot table size should also resize the UDP
72  *        socket buffers for existing UDP transports
73  */
74 static ctl_table xs_tunables_table[] = {
75 	{
76 		.ctl_name	= CTL_SLOTTABLE_UDP,
77 		.procname	= "udp_slot_table_entries",
78 		.data		= &xprt_udp_slot_table_entries,
79 		.maxlen		= sizeof(unsigned int),
80 		.mode		= 0644,
81 		.proc_handler	= &proc_dointvec_minmax,
82 		.strategy	= &sysctl_intvec,
83 		.extra1		= &min_slot_table_size,
84 		.extra2		= &max_slot_table_size
85 	},
86 	{
87 		.ctl_name	= CTL_SLOTTABLE_TCP,
88 		.procname	= "tcp_slot_table_entries",
89 		.data		= &xprt_tcp_slot_table_entries,
90 		.maxlen		= sizeof(unsigned int),
91 		.mode		= 0644,
92 		.proc_handler	= &proc_dointvec_minmax,
93 		.strategy	= &sysctl_intvec,
94 		.extra1		= &min_slot_table_size,
95 		.extra2		= &max_slot_table_size
96 	},
97 	{
98 		.ctl_name	= CTL_MIN_RESVPORT,
99 		.procname	= "min_resvport",
100 		.data		= &xprt_min_resvport,
101 		.maxlen		= sizeof(unsigned int),
102 		.mode		= 0644,
103 		.proc_handler	= &proc_dointvec_minmax,
104 		.strategy	= &sysctl_intvec,
105 		.extra1		= &xprt_min_resvport_limit,
106 		.extra2		= &xprt_max_resvport_limit
107 	},
108 	{
109 		.ctl_name	= CTL_MAX_RESVPORT,
110 		.procname	= "max_resvport",
111 		.data		= &xprt_max_resvport,
112 		.maxlen		= sizeof(unsigned int),
113 		.mode		= 0644,
114 		.proc_handler	= &proc_dointvec_minmax,
115 		.strategy	= &sysctl_intvec,
116 		.extra1		= &xprt_min_resvport_limit,
117 		.extra2		= &xprt_max_resvport_limit
118 	},
119 	{
120 		.ctl_name = 0,
121 	},
122 };
123 
124 static ctl_table sunrpc_table[] = {
125 	{
126 		.ctl_name	= CTL_SUNRPC,
127 		.procname	= "sunrpc",
128 		.mode		= 0555,
129 		.child		= xs_tunables_table
130 	},
131 	{
132 		.ctl_name = 0,
133 	},
134 };
135 
136 #endif
137 
138 /*
139  * How many times to try sending a request on a socket before waiting
140  * for the socket buffer to clear.
141  */
142 #define XS_SENDMSG_RETRY	(10U)
143 
144 /*
145  * Time out for an RPC UDP socket connect.  UDP socket connects are
146  * synchronous, but we set a timeout anyway in case of resource
147  * exhaustion on the local host.
148  */
149 #define XS_UDP_CONN_TO		(5U * HZ)
150 
151 /*
152  * Wait duration for an RPC TCP connection to be established.  Solaris
153  * NFS over TCP uses 60 seconds, for example, which is in line with how
154  * long a server takes to reboot.
155  */
156 #define XS_TCP_CONN_TO		(60U * HZ)
157 
158 /*
159  * Wait duration for a reply from the RPC portmapper.
160  */
161 #define XS_BIND_TO		(60U * HZ)
162 
163 /*
164  * Delay if a UDP socket connect error occurs.  This is most likely some
165  * kind of resource problem on the local host.
166  */
167 #define XS_UDP_REEST_TO		(2U * HZ)
168 
169 /*
170  * The reestablish timeout allows clients to delay for a bit before attempting
171  * to reconnect to a server that just dropped our connection.
172  *
173  * We implement an exponential backoff when trying to reestablish a TCP
174  * transport connection with the server.  Some servers like to drop a TCP
175  * connection when they are overworked, so we start with a short timeout and
176  * increase over time if the server is down or not responding.
177  */
178 #define XS_TCP_INIT_REEST_TO	(3U * HZ)
179 #define XS_TCP_MAX_REEST_TO	(5U * 60 * HZ)
180 
181 /*
182  * TCP idle timeout; client drops the transport socket if it is idle
183  * for this long.  Note that we also timeout UDP sockets to prevent
184  * holding port numbers when there is no RPC traffic.
185  */
186 #define XS_IDLE_DISC_TO		(5U * 60 * HZ)
187 
188 #ifdef RPC_DEBUG
189 # undef  RPC_DEBUG_DATA
190 # define RPCDBG_FACILITY	RPCDBG_TRANS
191 #endif
192 
193 #ifdef RPC_DEBUG_DATA
194 static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
195 {
196 	u8 *buf = (u8 *) packet;
197 	int j;
198 
199 	dprintk("RPC:       %s\n", msg);
200 	for (j = 0; j < count && j < 128; j += 4) {
201 		if (!(j & 31)) {
202 			if (j)
203 				dprintk("\n");
204 			dprintk("0x%04x ", j);
205 		}
206 		dprintk("%02x%02x%02x%02x ",
207 			buf[j], buf[j+1], buf[j+2], buf[j+3]);
208 	}
209 	dprintk("\n");
210 }
211 #else
212 static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
213 {
214 	/* NOP */
215 }
216 #endif
217 
218 struct sock_xprt {
219 	struct rpc_xprt		xprt;
220 
221 	/*
222 	 * Network layer
223 	 */
224 	struct socket *		sock;
225 	struct sock *		inet;
226 
227 	/*
228 	 * State of TCP reply receive
229 	 */
230 	__be32			tcp_fraghdr,
231 				tcp_xid;
232 
233 	u32			tcp_offset,
234 				tcp_reclen;
235 
236 	unsigned long		tcp_copied,
237 				tcp_flags;
238 
239 	/*
240 	 * Connection of transports
241 	 */
242 	struct delayed_work	connect_worker;
243 	struct sockaddr_storage	addr;
244 	unsigned short		port;
245 
246 	/*
247 	 * UDP socket buffer size parameters
248 	 */
249 	size_t			rcvsize,
250 				sndsize;
251 
252 	/*
253 	 * Saved socket callback addresses
254 	 */
255 	void			(*old_data_ready)(struct sock *, int);
256 	void			(*old_state_change)(struct sock *);
257 	void			(*old_write_space)(struct sock *);
258 };
259 
260 /*
261  * TCP receive state flags
262  */
263 #define TCP_RCV_LAST_FRAG	(1UL << 0)
264 #define TCP_RCV_COPY_FRAGHDR	(1UL << 1)
265 #define TCP_RCV_COPY_XID	(1UL << 2)
266 #define TCP_RCV_COPY_DATA	(1UL << 3)
267 
268 static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
269 {
270 	return (struct sockaddr *) &xprt->addr;
271 }
272 
273 static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
274 {
275 	return (struct sockaddr_in *) &xprt->addr;
276 }
277 
278 static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
279 {
280 	return (struct sockaddr_in6 *) &xprt->addr;
281 }
282 
283 static void xs_format_ipv4_peer_addresses(struct rpc_xprt *xprt)
284 {
285 	struct sockaddr_in *addr = xs_addr_in(xprt);
286 	char *buf;
287 
288 	buf = kzalloc(20, GFP_KERNEL);
289 	if (buf) {
290 		snprintf(buf, 20, NIPQUAD_FMT,
291 				NIPQUAD(addr->sin_addr.s_addr));
292 	}
293 	xprt->address_strings[RPC_DISPLAY_ADDR] = buf;
294 
295 	buf = kzalloc(8, GFP_KERNEL);
296 	if (buf) {
297 		snprintf(buf, 8, "%u",
298 				ntohs(addr->sin_port));
299 	}
300 	xprt->address_strings[RPC_DISPLAY_PORT] = buf;
301 
302 	buf = kzalloc(8, GFP_KERNEL);
303 	if (buf) {
304 		if (xprt->prot == IPPROTO_UDP)
305 			snprintf(buf, 8, "udp");
306 		else
307 			snprintf(buf, 8, "tcp");
308 	}
309 	xprt->address_strings[RPC_DISPLAY_PROTO] = buf;
310 
311 	buf = kzalloc(48, GFP_KERNEL);
312 	if (buf) {
313 		snprintf(buf, 48, "addr="NIPQUAD_FMT" port=%u proto=%s",
314 			NIPQUAD(addr->sin_addr.s_addr),
315 			ntohs(addr->sin_port),
316 			xprt->prot == IPPROTO_UDP ? "udp" : "tcp");
317 	}
318 	xprt->address_strings[RPC_DISPLAY_ALL] = buf;
319 
320 	buf = kzalloc(10, GFP_KERNEL);
321 	if (buf) {
322 		snprintf(buf, 10, "%02x%02x%02x%02x",
323 				NIPQUAD(addr->sin_addr.s_addr));
324 	}
325 	xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = buf;
326 
327 	buf = kzalloc(8, GFP_KERNEL);
328 	if (buf) {
329 		snprintf(buf, 8, "%4hx",
330 				ntohs(addr->sin_port));
331 	}
332 	xprt->address_strings[RPC_DISPLAY_HEX_PORT] = buf;
333 
334 	buf = kzalloc(30, GFP_KERNEL);
335 	if (buf) {
336 		snprintf(buf, 30, NIPQUAD_FMT".%u.%u",
337 				NIPQUAD(addr->sin_addr.s_addr),
338 				ntohs(addr->sin_port) >> 8,
339 				ntohs(addr->sin_port) & 0xff);
340 	}
341 	xprt->address_strings[RPC_DISPLAY_UNIVERSAL_ADDR] = buf;
342 
343 	xprt->address_strings[RPC_DISPLAY_NETID] =
344 		kstrdup(xprt->prot == IPPROTO_UDP ?
345 			RPCBIND_NETID_UDP : RPCBIND_NETID_TCP, GFP_KERNEL);
346 }
347 
348 static void xs_format_ipv6_peer_addresses(struct rpc_xprt *xprt)
349 {
350 	struct sockaddr_in6 *addr = xs_addr_in6(xprt);
351 	char *buf;
352 
353 	buf = kzalloc(40, GFP_KERNEL);
354 	if (buf) {
355 		snprintf(buf, 40, NIP6_FMT,
356 				NIP6(addr->sin6_addr));
357 	}
358 	xprt->address_strings[RPC_DISPLAY_ADDR] = buf;
359 
360 	buf = kzalloc(8, GFP_KERNEL);
361 	if (buf) {
362 		snprintf(buf, 8, "%u",
363 				ntohs(addr->sin6_port));
364 	}
365 	xprt->address_strings[RPC_DISPLAY_PORT] = buf;
366 
367 	buf = kzalloc(8, GFP_KERNEL);
368 	if (buf) {
369 		if (xprt->prot == IPPROTO_UDP)
370 			snprintf(buf, 8, "udp");
371 		else
372 			snprintf(buf, 8, "tcp");
373 	}
374 	xprt->address_strings[RPC_DISPLAY_PROTO] = buf;
375 
376 	buf = kzalloc(64, GFP_KERNEL);
377 	if (buf) {
378 		snprintf(buf, 64, "addr="NIP6_FMT" port=%u proto=%s",
379 				NIP6(addr->sin6_addr),
380 				ntohs(addr->sin6_port),
381 				xprt->prot == IPPROTO_UDP ? "udp" : "tcp");
382 	}
383 	xprt->address_strings[RPC_DISPLAY_ALL] = buf;
384 
385 	buf = kzalloc(36, GFP_KERNEL);
386 	if (buf) {
387 		snprintf(buf, 36, NIP6_SEQFMT,
388 				NIP6(addr->sin6_addr));
389 	}
390 	xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = buf;
391 
392 	buf = kzalloc(8, GFP_KERNEL);
393 	if (buf) {
394 		snprintf(buf, 8, "%4hx",
395 				ntohs(addr->sin6_port));
396 	}
397 	xprt->address_strings[RPC_DISPLAY_HEX_PORT] = buf;
398 
399 	buf = kzalloc(50, GFP_KERNEL);
400 	if (buf) {
401 		snprintf(buf, 50, NIP6_FMT".%u.%u",
402 				NIP6(addr->sin6_addr),
403 				ntohs(addr->sin6_port) >> 8,
404 				ntohs(addr->sin6_port) & 0xff);
405 	}
406 	xprt->address_strings[RPC_DISPLAY_UNIVERSAL_ADDR] = buf;
407 
408 	xprt->address_strings[RPC_DISPLAY_NETID] =
409 		kstrdup(xprt->prot == IPPROTO_UDP ?
410 			RPCBIND_NETID_UDP6 : RPCBIND_NETID_TCP6, GFP_KERNEL);
411 }
412 
413 static void xs_free_peer_addresses(struct rpc_xprt *xprt)
414 {
415 	int i;
416 
417 	for (i = 0; i < RPC_DISPLAY_MAX; i++)
418 		kfree(xprt->address_strings[i]);
419 }
420 
421 #define XS_SENDMSG_FLAGS	(MSG_DONTWAIT | MSG_NOSIGNAL)
422 
423 static int xs_send_kvec(struct socket *sock, struct sockaddr *addr, int addrlen, struct kvec *vec, unsigned int base, int more)
424 {
425 	struct msghdr msg = {
426 		.msg_name	= addr,
427 		.msg_namelen	= addrlen,
428 		.msg_flags	= XS_SENDMSG_FLAGS | (more ? MSG_MORE : 0),
429 	};
430 	struct kvec iov = {
431 		.iov_base	= vec->iov_base + base,
432 		.iov_len	= vec->iov_len - base,
433 	};
434 
435 	if (iov.iov_len != 0)
436 		return kernel_sendmsg(sock, &msg, &iov, 1, iov.iov_len);
437 	return kernel_sendmsg(sock, &msg, NULL, 0, 0);
438 }
439 
440 static int xs_send_pagedata(struct socket *sock, struct xdr_buf *xdr, unsigned int base, int more)
441 {
442 	struct page **ppage;
443 	unsigned int remainder;
444 	int err, sent = 0;
445 
446 	remainder = xdr->page_len - base;
447 	base += xdr->page_base;
448 	ppage = xdr->pages + (base >> PAGE_SHIFT);
449 	base &= ~PAGE_MASK;
450 	for(;;) {
451 		unsigned int len = min_t(unsigned int, PAGE_SIZE - base, remainder);
452 		int flags = XS_SENDMSG_FLAGS;
453 
454 		remainder -= len;
455 		if (remainder != 0 || more)
456 			flags |= MSG_MORE;
457 		err = sock->ops->sendpage(sock, *ppage, base, len, flags);
458 		if (remainder == 0 || err != len)
459 			break;
460 		sent += err;
461 		ppage++;
462 		base = 0;
463 	}
464 	if (sent == 0)
465 		return err;
466 	if (err > 0)
467 		sent += err;
468 	return sent;
469 }
470 
471 /**
472  * xs_sendpages - write pages directly to a socket
473  * @sock: socket to send on
474  * @addr: UDP only -- address of destination
475  * @addrlen: UDP only -- length of destination address
476  * @xdr: buffer containing this request
477  * @base: starting position in the buffer
478  *
479  */
480 static int xs_sendpages(struct socket *sock, struct sockaddr *addr, int addrlen, struct xdr_buf *xdr, unsigned int base)
481 {
482 	unsigned int remainder = xdr->len - base;
483 	int err, sent = 0;
484 
485 	if (unlikely(!sock))
486 		return -ENOTCONN;
487 
488 	clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags);
489 	if (base != 0) {
490 		addr = NULL;
491 		addrlen = 0;
492 	}
493 
494 	if (base < xdr->head[0].iov_len || addr != NULL) {
495 		unsigned int len = xdr->head[0].iov_len - base;
496 		remainder -= len;
497 		err = xs_send_kvec(sock, addr, addrlen, &xdr->head[0], base, remainder != 0);
498 		if (remainder == 0 || err != len)
499 			goto out;
500 		sent += err;
501 		base = 0;
502 	} else
503 		base -= xdr->head[0].iov_len;
504 
505 	if (base < xdr->page_len) {
506 		unsigned int len = xdr->page_len - base;
507 		remainder -= len;
508 		err = xs_send_pagedata(sock, xdr, base, remainder != 0);
509 		if (remainder == 0 || err != len)
510 			goto out;
511 		sent += err;
512 		base = 0;
513 	} else
514 		base -= xdr->page_len;
515 
516 	if (base >= xdr->tail[0].iov_len)
517 		return sent;
518 	err = xs_send_kvec(sock, NULL, 0, &xdr->tail[0], base, 0);
519 out:
520 	if (sent == 0)
521 		return err;
522 	if (err > 0)
523 		sent += err;
524 	return sent;
525 }
526 
527 /**
528  * xs_nospace - place task on wait queue if transmit was incomplete
529  * @task: task to put to sleep
530  *
531  */
532 static void xs_nospace(struct rpc_task *task)
533 {
534 	struct rpc_rqst *req = task->tk_rqstp;
535 	struct rpc_xprt *xprt = req->rq_xprt;
536 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
537 
538 	dprintk("RPC: %5u xmit incomplete (%u left of %u)\n",
539 			task->tk_pid, req->rq_slen - req->rq_bytes_sent,
540 			req->rq_slen);
541 
542 	if (test_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags)) {
543 		/* Protect against races with write_space */
544 		spin_lock_bh(&xprt->transport_lock);
545 
546 		/* Don't race with disconnect */
547 		if (!xprt_connected(xprt))
548 			task->tk_status = -ENOTCONN;
549 		else if (test_bit(SOCK_NOSPACE, &transport->sock->flags))
550 			xprt_wait_for_buffer_space(task);
551 
552 		spin_unlock_bh(&xprt->transport_lock);
553 	} else
554 		/* Keep holding the socket if it is blocked */
555 		rpc_delay(task, HZ>>4);
556 }
557 
558 /**
559  * xs_udp_send_request - write an RPC request to a UDP socket
560  * @task: address of RPC task that manages the state of an RPC request
561  *
562  * Return values:
563  *        0:	The request has been sent
564  *   EAGAIN:	The socket was blocked, please call again later to
565  *		complete the request
566  * ENOTCONN:	Caller needs to invoke connect logic then call again
567  *    other:	Some other error occured, the request was not sent
568  */
569 static int xs_udp_send_request(struct rpc_task *task)
570 {
571 	struct rpc_rqst *req = task->tk_rqstp;
572 	struct rpc_xprt *xprt = req->rq_xprt;
573 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
574 	struct xdr_buf *xdr = &req->rq_snd_buf;
575 	int status;
576 
577 	xs_pktdump("packet data:",
578 				req->rq_svec->iov_base,
579 				req->rq_svec->iov_len);
580 
581 	req->rq_xtime = jiffies;
582 	status = xs_sendpages(transport->sock,
583 			      xs_addr(xprt),
584 			      xprt->addrlen, xdr,
585 			      req->rq_bytes_sent);
586 
587 	dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
588 			xdr->len - req->rq_bytes_sent, status);
589 
590 	if (status >= 0) {
591 		task->tk_bytes_sent += status;
592 		if (status >= req->rq_slen)
593 			return 0;
594 		/* Still some bytes left; set up for a retry later. */
595 		status = -EAGAIN;
596 	}
597 
598 	switch (status) {
599 	case -ENETUNREACH:
600 	case -EPIPE:
601 	case -ECONNREFUSED:
602 		/* When the server has died, an ICMP port unreachable message
603 		 * prompts ECONNREFUSED. */
604 		break;
605 	case -EAGAIN:
606 		xs_nospace(task);
607 		break;
608 	default:
609 		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
610 			-status);
611 		break;
612 	}
613 
614 	return status;
615 }
616 
617 static inline void xs_encode_tcp_record_marker(struct xdr_buf *buf)
618 {
619 	u32 reclen = buf->len - sizeof(rpc_fraghdr);
620 	rpc_fraghdr *base = buf->head[0].iov_base;
621 	*base = htonl(RPC_LAST_STREAM_FRAGMENT | reclen);
622 }
623 
624 /**
625  * xs_tcp_send_request - write an RPC request to a TCP socket
626  * @task: address of RPC task that manages the state of an RPC request
627  *
628  * Return values:
629  *        0:	The request has been sent
630  *   EAGAIN:	The socket was blocked, please call again later to
631  *		complete the request
632  * ENOTCONN:	Caller needs to invoke connect logic then call again
633  *    other:	Some other error occured, the request was not sent
634  *
635  * XXX: In the case of soft timeouts, should we eventually give up
636  *	if sendmsg is not able to make progress?
637  */
638 static int xs_tcp_send_request(struct rpc_task *task)
639 {
640 	struct rpc_rqst *req = task->tk_rqstp;
641 	struct rpc_xprt *xprt = req->rq_xprt;
642 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
643 	struct xdr_buf *xdr = &req->rq_snd_buf;
644 	int status;
645 	unsigned int retry = 0;
646 
647 	xs_encode_tcp_record_marker(&req->rq_snd_buf);
648 
649 	xs_pktdump("packet data:",
650 				req->rq_svec->iov_base,
651 				req->rq_svec->iov_len);
652 
653 	/* Continue transmitting the packet/record. We must be careful
654 	 * to cope with writespace callbacks arriving _after_ we have
655 	 * called sendmsg(). */
656 	while (1) {
657 		req->rq_xtime = jiffies;
658 		status = xs_sendpages(transport->sock,
659 					NULL, 0, xdr, req->rq_bytes_sent);
660 
661 		dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
662 				xdr->len - req->rq_bytes_sent, status);
663 
664 		if (unlikely(status < 0))
665 			break;
666 
667 		/* If we've sent the entire packet, immediately
668 		 * reset the count of bytes sent. */
669 		req->rq_bytes_sent += status;
670 		task->tk_bytes_sent += status;
671 		if (likely(req->rq_bytes_sent >= req->rq_slen)) {
672 			req->rq_bytes_sent = 0;
673 			return 0;
674 		}
675 
676 		status = -EAGAIN;
677 		if (retry++ > XS_SENDMSG_RETRY)
678 			break;
679 	}
680 
681 	switch (status) {
682 	case -EAGAIN:
683 		xs_nospace(task);
684 		break;
685 	case -ECONNREFUSED:
686 	case -ECONNRESET:
687 	case -ENOTCONN:
688 	case -EPIPE:
689 		status = -ENOTCONN;
690 		break;
691 	default:
692 		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
693 			-status);
694 		xprt_disconnect(xprt);
695 		break;
696 	}
697 
698 	return status;
699 }
700 
701 /**
702  * xs_tcp_release_xprt - clean up after a tcp transmission
703  * @xprt: transport
704  * @task: rpc task
705  *
706  * This cleans up if an error causes us to abort the transmission of a request.
707  * In this case, the socket may need to be reset in order to avoid confusing
708  * the server.
709  */
710 static void xs_tcp_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task)
711 {
712 	struct rpc_rqst *req;
713 
714 	if (task != xprt->snd_task)
715 		return;
716 	if (task == NULL)
717 		goto out_release;
718 	req = task->tk_rqstp;
719 	if (req->rq_bytes_sent == 0)
720 		goto out_release;
721 	if (req->rq_bytes_sent == req->rq_snd_buf.len)
722 		goto out_release;
723 	set_bit(XPRT_CLOSE_WAIT, &task->tk_xprt->state);
724 out_release:
725 	xprt_release_xprt(xprt, task);
726 }
727 
728 /**
729  * xs_close - close a socket
730  * @xprt: transport
731  *
732  * This is used when all requests are complete; ie, no DRC state remains
733  * on the server we want to save.
734  */
735 static void xs_close(struct rpc_xprt *xprt)
736 {
737 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
738 	struct socket *sock = transport->sock;
739 	struct sock *sk = transport->inet;
740 
741 	if (!sk)
742 		goto clear_close_wait;
743 
744 	dprintk("RPC:       xs_close xprt %p\n", xprt);
745 
746 	write_lock_bh(&sk->sk_callback_lock);
747 	transport->inet = NULL;
748 	transport->sock = NULL;
749 
750 	sk->sk_user_data = NULL;
751 	sk->sk_data_ready = transport->old_data_ready;
752 	sk->sk_state_change = transport->old_state_change;
753 	sk->sk_write_space = transport->old_write_space;
754 	write_unlock_bh(&sk->sk_callback_lock);
755 
756 	sk->sk_no_check = 0;
757 
758 	sock_release(sock);
759 clear_close_wait:
760 	smp_mb__before_clear_bit();
761 	clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
762 	smp_mb__after_clear_bit();
763 }
764 
765 /**
766  * xs_destroy - prepare to shutdown a transport
767  * @xprt: doomed transport
768  *
769  */
770 static void xs_destroy(struct rpc_xprt *xprt)
771 {
772 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
773 
774 	dprintk("RPC:       xs_destroy xprt %p\n", xprt);
775 
776 	cancel_rearming_delayed_work(&transport->connect_worker);
777 
778 	xprt_disconnect(xprt);
779 	xs_close(xprt);
780 	xs_free_peer_addresses(xprt);
781 	kfree(xprt->slot);
782 	kfree(xprt);
783 	module_put(THIS_MODULE);
784 }
785 
786 static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
787 {
788 	return (struct rpc_xprt *) sk->sk_user_data;
789 }
790 
791 /**
792  * xs_udp_data_ready - "data ready" callback for UDP sockets
793  * @sk: socket with data to read
794  * @len: how much data to read
795  *
796  */
797 static void xs_udp_data_ready(struct sock *sk, int len)
798 {
799 	struct rpc_task *task;
800 	struct rpc_xprt *xprt;
801 	struct rpc_rqst *rovr;
802 	struct sk_buff *skb;
803 	int err, repsize, copied;
804 	u32 _xid;
805 	__be32 *xp;
806 
807 	read_lock(&sk->sk_callback_lock);
808 	dprintk("RPC:       xs_udp_data_ready...\n");
809 	if (!(xprt = xprt_from_sock(sk)))
810 		goto out;
811 
812 	if ((skb = skb_recv_datagram(sk, 0, 1, &err)) == NULL)
813 		goto out;
814 
815 	if (xprt->shutdown)
816 		goto dropit;
817 
818 	repsize = skb->len - sizeof(struct udphdr);
819 	if (repsize < 4) {
820 		dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
821 		goto dropit;
822 	}
823 
824 	/* Copy the XID from the skb... */
825 	xp = skb_header_pointer(skb, sizeof(struct udphdr),
826 				sizeof(_xid), &_xid);
827 	if (xp == NULL)
828 		goto dropit;
829 
830 	/* Look up and lock the request corresponding to the given XID */
831 	spin_lock(&xprt->transport_lock);
832 	rovr = xprt_lookup_rqst(xprt, *xp);
833 	if (!rovr)
834 		goto out_unlock;
835 	task = rovr->rq_task;
836 
837 	if ((copied = rovr->rq_private_buf.buflen) > repsize)
838 		copied = repsize;
839 
840 	/* Suck it into the iovec, verify checksum if not done by hw. */
841 	if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb))
842 		goto out_unlock;
843 
844 	/* Something worked... */
845 	dst_confirm(skb->dst);
846 
847 	xprt_adjust_cwnd(task, copied);
848 	xprt_update_rtt(task);
849 	xprt_complete_rqst(task, copied);
850 
851  out_unlock:
852 	spin_unlock(&xprt->transport_lock);
853  dropit:
854 	skb_free_datagram(sk, skb);
855  out:
856 	read_unlock(&sk->sk_callback_lock);
857 }
858 
859 static inline void xs_tcp_read_fraghdr(struct rpc_xprt *xprt, struct xdr_skb_reader *desc)
860 {
861 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
862 	size_t len, used;
863 	char *p;
864 
865 	p = ((char *) &transport->tcp_fraghdr) + transport->tcp_offset;
866 	len = sizeof(transport->tcp_fraghdr) - transport->tcp_offset;
867 	used = xdr_skb_read_bits(desc, p, len);
868 	transport->tcp_offset += used;
869 	if (used != len)
870 		return;
871 
872 	transport->tcp_reclen = ntohl(transport->tcp_fraghdr);
873 	if (transport->tcp_reclen & RPC_LAST_STREAM_FRAGMENT)
874 		transport->tcp_flags |= TCP_RCV_LAST_FRAG;
875 	else
876 		transport->tcp_flags &= ~TCP_RCV_LAST_FRAG;
877 	transport->tcp_reclen &= RPC_FRAGMENT_SIZE_MASK;
878 
879 	transport->tcp_flags &= ~TCP_RCV_COPY_FRAGHDR;
880 	transport->tcp_offset = 0;
881 
882 	/* Sanity check of the record length */
883 	if (unlikely(transport->tcp_reclen < 4)) {
884 		dprintk("RPC:       invalid TCP record fragment length\n");
885 		xprt_disconnect(xprt);
886 		return;
887 	}
888 	dprintk("RPC:       reading TCP record fragment of length %d\n",
889 			transport->tcp_reclen);
890 }
891 
892 static void xs_tcp_check_fraghdr(struct sock_xprt *transport)
893 {
894 	if (transport->tcp_offset == transport->tcp_reclen) {
895 		transport->tcp_flags |= TCP_RCV_COPY_FRAGHDR;
896 		transport->tcp_offset = 0;
897 		if (transport->tcp_flags & TCP_RCV_LAST_FRAG) {
898 			transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
899 			transport->tcp_flags |= TCP_RCV_COPY_XID;
900 			transport->tcp_copied = 0;
901 		}
902 	}
903 }
904 
905 static inline void xs_tcp_read_xid(struct sock_xprt *transport, struct xdr_skb_reader *desc)
906 {
907 	size_t len, used;
908 	char *p;
909 
910 	len = sizeof(transport->tcp_xid) - transport->tcp_offset;
911 	dprintk("RPC:       reading XID (%Zu bytes)\n", len);
912 	p = ((char *) &transport->tcp_xid) + transport->tcp_offset;
913 	used = xdr_skb_read_bits(desc, p, len);
914 	transport->tcp_offset += used;
915 	if (used != len)
916 		return;
917 	transport->tcp_flags &= ~TCP_RCV_COPY_XID;
918 	transport->tcp_flags |= TCP_RCV_COPY_DATA;
919 	transport->tcp_copied = 4;
920 	dprintk("RPC:       reading reply for XID %08x\n",
921 			ntohl(transport->tcp_xid));
922 	xs_tcp_check_fraghdr(transport);
923 }
924 
925 static inline void xs_tcp_read_request(struct rpc_xprt *xprt, struct xdr_skb_reader *desc)
926 {
927 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
928 	struct rpc_rqst *req;
929 	struct xdr_buf *rcvbuf;
930 	size_t len;
931 	ssize_t r;
932 
933 	/* Find and lock the request corresponding to this xid */
934 	spin_lock(&xprt->transport_lock);
935 	req = xprt_lookup_rqst(xprt, transport->tcp_xid);
936 	if (!req) {
937 		transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
938 		dprintk("RPC:       XID %08x request not found!\n",
939 				ntohl(transport->tcp_xid));
940 		spin_unlock(&xprt->transport_lock);
941 		return;
942 	}
943 
944 	rcvbuf = &req->rq_private_buf;
945 	len = desc->count;
946 	if (len > transport->tcp_reclen - transport->tcp_offset) {
947 		struct xdr_skb_reader my_desc;
948 
949 		len = transport->tcp_reclen - transport->tcp_offset;
950 		memcpy(&my_desc, desc, sizeof(my_desc));
951 		my_desc.count = len;
952 		r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied,
953 					  &my_desc, xdr_skb_read_bits);
954 		desc->count -= r;
955 		desc->offset += r;
956 	} else
957 		r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied,
958 					  desc, xdr_skb_read_bits);
959 
960 	if (r > 0) {
961 		transport->tcp_copied += r;
962 		transport->tcp_offset += r;
963 	}
964 	if (r != len) {
965 		/* Error when copying to the receive buffer,
966 		 * usually because we weren't able to allocate
967 		 * additional buffer pages. All we can do now
968 		 * is turn off TCP_RCV_COPY_DATA, so the request
969 		 * will not receive any additional updates,
970 		 * and time out.
971 		 * Any remaining data from this record will
972 		 * be discarded.
973 		 */
974 		transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
975 		dprintk("RPC:       XID %08x truncated request\n",
976 				ntohl(transport->tcp_xid));
977 		dprintk("RPC:       xprt = %p, tcp_copied = %lu, "
978 				"tcp_offset = %u, tcp_reclen = %u\n",
979 				xprt, transport->tcp_copied,
980 				transport->tcp_offset, transport->tcp_reclen);
981 		goto out;
982 	}
983 
984 	dprintk("RPC:       XID %08x read %Zd bytes\n",
985 			ntohl(transport->tcp_xid), r);
986 	dprintk("RPC:       xprt = %p, tcp_copied = %lu, tcp_offset = %u, "
987 			"tcp_reclen = %u\n", xprt, transport->tcp_copied,
988 			transport->tcp_offset, transport->tcp_reclen);
989 
990 	if (transport->tcp_copied == req->rq_private_buf.buflen)
991 		transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
992 	else if (transport->tcp_offset == transport->tcp_reclen) {
993 		if (transport->tcp_flags & TCP_RCV_LAST_FRAG)
994 			transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
995 	}
996 
997 out:
998 	if (!(transport->tcp_flags & TCP_RCV_COPY_DATA))
999 		xprt_complete_rqst(req->rq_task, transport->tcp_copied);
1000 	spin_unlock(&xprt->transport_lock);
1001 	xs_tcp_check_fraghdr(transport);
1002 }
1003 
1004 static inline void xs_tcp_read_discard(struct sock_xprt *transport, struct xdr_skb_reader *desc)
1005 {
1006 	size_t len;
1007 
1008 	len = transport->tcp_reclen - transport->tcp_offset;
1009 	if (len > desc->count)
1010 		len = desc->count;
1011 	desc->count -= len;
1012 	desc->offset += len;
1013 	transport->tcp_offset += len;
1014 	dprintk("RPC:       discarded %Zu bytes\n", len);
1015 	xs_tcp_check_fraghdr(transport);
1016 }
1017 
1018 static int xs_tcp_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, unsigned int offset, size_t len)
1019 {
1020 	struct rpc_xprt *xprt = rd_desc->arg.data;
1021 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1022 	struct xdr_skb_reader desc = {
1023 		.skb	= skb,
1024 		.offset	= offset,
1025 		.count	= len,
1026 	};
1027 
1028 	dprintk("RPC:       xs_tcp_data_recv started\n");
1029 	do {
1030 		/* Read in a new fragment marker if necessary */
1031 		/* Can we ever really expect to get completely empty fragments? */
1032 		if (transport->tcp_flags & TCP_RCV_COPY_FRAGHDR) {
1033 			xs_tcp_read_fraghdr(xprt, &desc);
1034 			continue;
1035 		}
1036 		/* Read in the xid if necessary */
1037 		if (transport->tcp_flags & TCP_RCV_COPY_XID) {
1038 			xs_tcp_read_xid(transport, &desc);
1039 			continue;
1040 		}
1041 		/* Read in the request data */
1042 		if (transport->tcp_flags & TCP_RCV_COPY_DATA) {
1043 			xs_tcp_read_request(xprt, &desc);
1044 			continue;
1045 		}
1046 		/* Skip over any trailing bytes on short reads */
1047 		xs_tcp_read_discard(transport, &desc);
1048 	} while (desc.count);
1049 	dprintk("RPC:       xs_tcp_data_recv done\n");
1050 	return len - desc.count;
1051 }
1052 
1053 /**
1054  * xs_tcp_data_ready - "data ready" callback for TCP sockets
1055  * @sk: socket with data to read
1056  * @bytes: how much data to read
1057  *
1058  */
1059 static void xs_tcp_data_ready(struct sock *sk, int bytes)
1060 {
1061 	struct rpc_xprt *xprt;
1062 	read_descriptor_t rd_desc;
1063 
1064 	dprintk("RPC:       xs_tcp_data_ready...\n");
1065 
1066 	read_lock(&sk->sk_callback_lock);
1067 	if (!(xprt = xprt_from_sock(sk)))
1068 		goto out;
1069 	if (xprt->shutdown)
1070 		goto out;
1071 
1072 	/* We use rd_desc to pass struct xprt to xs_tcp_data_recv */
1073 	rd_desc.arg.data = xprt;
1074 	rd_desc.count = 65536;
1075 	tcp_read_sock(sk, &rd_desc, xs_tcp_data_recv);
1076 out:
1077 	read_unlock(&sk->sk_callback_lock);
1078 }
1079 
1080 /**
1081  * xs_tcp_state_change - callback to handle TCP socket state changes
1082  * @sk: socket whose state has changed
1083  *
1084  */
1085 static void xs_tcp_state_change(struct sock *sk)
1086 {
1087 	struct rpc_xprt *xprt;
1088 
1089 	read_lock(&sk->sk_callback_lock);
1090 	if (!(xprt = xprt_from_sock(sk)))
1091 		goto out;
1092 	dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1093 	dprintk("RPC:       state %x conn %d dead %d zapped %d\n",
1094 			sk->sk_state, xprt_connected(xprt),
1095 			sock_flag(sk, SOCK_DEAD),
1096 			sock_flag(sk, SOCK_ZAPPED));
1097 
1098 	switch (sk->sk_state) {
1099 	case TCP_ESTABLISHED:
1100 		spin_lock_bh(&xprt->transport_lock);
1101 		if (!xprt_test_and_set_connected(xprt)) {
1102 			struct sock_xprt *transport = container_of(xprt,
1103 					struct sock_xprt, xprt);
1104 
1105 			/* Reset TCP record info */
1106 			transport->tcp_offset = 0;
1107 			transport->tcp_reclen = 0;
1108 			transport->tcp_copied = 0;
1109 			transport->tcp_flags =
1110 				TCP_RCV_COPY_FRAGHDR | TCP_RCV_COPY_XID;
1111 
1112 			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1113 			xprt_wake_pending_tasks(xprt, 0);
1114 		}
1115 		spin_unlock_bh(&xprt->transport_lock);
1116 		break;
1117 	case TCP_SYN_SENT:
1118 	case TCP_SYN_RECV:
1119 		break;
1120 	case TCP_CLOSE_WAIT:
1121 		/* Try to schedule an autoclose RPC calls */
1122 		set_bit(XPRT_CLOSE_WAIT, &xprt->state);
1123 		if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0)
1124 			queue_work(rpciod_workqueue, &xprt->task_cleanup);
1125 	default:
1126 		xprt_disconnect(xprt);
1127 	}
1128  out:
1129 	read_unlock(&sk->sk_callback_lock);
1130 }
1131 
1132 /**
1133  * xs_udp_write_space - callback invoked when socket buffer space
1134  *                             becomes available
1135  * @sk: socket whose state has changed
1136  *
1137  * Called when more output buffer space is available for this socket.
1138  * We try not to wake our writers until they can make "significant"
1139  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1140  * with a bunch of small requests.
1141  */
1142 static void xs_udp_write_space(struct sock *sk)
1143 {
1144 	read_lock(&sk->sk_callback_lock);
1145 
1146 	/* from net/core/sock.c:sock_def_write_space */
1147 	if (sock_writeable(sk)) {
1148 		struct socket *sock;
1149 		struct rpc_xprt *xprt;
1150 
1151 		if (unlikely(!(sock = sk->sk_socket)))
1152 			goto out;
1153 		if (unlikely(!(xprt = xprt_from_sock(sk))))
1154 			goto out;
1155 		if (unlikely(!test_and_clear_bit(SOCK_NOSPACE, &sock->flags)))
1156 			goto out;
1157 
1158 		xprt_write_space(xprt);
1159 	}
1160 
1161  out:
1162 	read_unlock(&sk->sk_callback_lock);
1163 }
1164 
1165 /**
1166  * xs_tcp_write_space - callback invoked when socket buffer space
1167  *                             becomes available
1168  * @sk: socket whose state has changed
1169  *
1170  * Called when more output buffer space is available for this socket.
1171  * We try not to wake our writers until they can make "significant"
1172  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1173  * with a bunch of small requests.
1174  */
1175 static void xs_tcp_write_space(struct sock *sk)
1176 {
1177 	read_lock(&sk->sk_callback_lock);
1178 
1179 	/* from net/core/stream.c:sk_stream_write_space */
1180 	if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk)) {
1181 		struct socket *sock;
1182 		struct rpc_xprt *xprt;
1183 
1184 		if (unlikely(!(sock = sk->sk_socket)))
1185 			goto out;
1186 		if (unlikely(!(xprt = xprt_from_sock(sk))))
1187 			goto out;
1188 		if (unlikely(!test_and_clear_bit(SOCK_NOSPACE, &sock->flags)))
1189 			goto out;
1190 
1191 		xprt_write_space(xprt);
1192 	}
1193 
1194  out:
1195 	read_unlock(&sk->sk_callback_lock);
1196 }
1197 
1198 static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1199 {
1200 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1201 	struct sock *sk = transport->inet;
1202 
1203 	if (transport->rcvsize) {
1204 		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1205 		sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1206 	}
1207 	if (transport->sndsize) {
1208 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1209 		sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1210 		sk->sk_write_space(sk);
1211 	}
1212 }
1213 
1214 /**
1215  * xs_udp_set_buffer_size - set send and receive limits
1216  * @xprt: generic transport
1217  * @sndsize: requested size of send buffer, in bytes
1218  * @rcvsize: requested size of receive buffer, in bytes
1219  *
1220  * Set socket send and receive buffer size limits.
1221  */
1222 static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1223 {
1224 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1225 
1226 	transport->sndsize = 0;
1227 	if (sndsize)
1228 		transport->sndsize = sndsize + 1024;
1229 	transport->rcvsize = 0;
1230 	if (rcvsize)
1231 		transport->rcvsize = rcvsize + 1024;
1232 
1233 	xs_udp_do_set_buffer_size(xprt);
1234 }
1235 
1236 /**
1237  * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1238  * @task: task that timed out
1239  *
1240  * Adjust the congestion window after a retransmit timeout has occurred.
1241  */
1242 static void xs_udp_timer(struct rpc_task *task)
1243 {
1244 	xprt_adjust_cwnd(task, -ETIMEDOUT);
1245 }
1246 
1247 static unsigned short xs_get_random_port(void)
1248 {
1249 	unsigned short range = xprt_max_resvport - xprt_min_resvport;
1250 	unsigned short rand = (unsigned short) net_random() % range;
1251 	return rand + xprt_min_resvport;
1252 }
1253 
1254 /**
1255  * xs_set_port - reset the port number in the remote endpoint address
1256  * @xprt: generic transport
1257  * @port: new port number
1258  *
1259  */
1260 static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1261 {
1262 	struct sockaddr *addr = xs_addr(xprt);
1263 
1264 	dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1265 
1266 	switch (addr->sa_family) {
1267 	case AF_INET:
1268 		((struct sockaddr_in *)addr)->sin_port = htons(port);
1269 		break;
1270 	case AF_INET6:
1271 		((struct sockaddr_in6 *)addr)->sin6_port = htons(port);
1272 		break;
1273 	default:
1274 		BUG();
1275 	}
1276 }
1277 
1278 static int xs_bind4(struct sock_xprt *transport, struct socket *sock)
1279 {
1280 	struct sockaddr_in myaddr = {
1281 		.sin_family = AF_INET,
1282 	};
1283 	struct sockaddr_in *sa;
1284 	int err;
1285 	unsigned short port = transport->port;
1286 
1287 	if (!transport->xprt.resvport)
1288 		port = 0;
1289 	sa = (struct sockaddr_in *)&transport->addr;
1290 	myaddr.sin_addr = sa->sin_addr;
1291 	do {
1292 		myaddr.sin_port = htons(port);
1293 		err = kernel_bind(sock, (struct sockaddr *) &myaddr,
1294 						sizeof(myaddr));
1295 		if (!transport->xprt.resvport)
1296 			break;
1297 		if (err == 0) {
1298 			transport->port = port;
1299 			break;
1300 		}
1301 		if (port <= xprt_min_resvport)
1302 			port = xprt_max_resvport;
1303 		else
1304 			port--;
1305 	} while (err == -EADDRINUSE && port != transport->port);
1306 	dprintk("RPC:       %s "NIPQUAD_FMT":%u: %s (%d)\n",
1307 			__FUNCTION__, NIPQUAD(myaddr.sin_addr),
1308 			port, err ? "failed" : "ok", err);
1309 	return err;
1310 }
1311 
1312 static int xs_bind6(struct sock_xprt *transport, struct socket *sock)
1313 {
1314 	struct sockaddr_in6 myaddr = {
1315 		.sin6_family = AF_INET6,
1316 	};
1317 	struct sockaddr_in6 *sa;
1318 	int err;
1319 	unsigned short port = transport->port;
1320 
1321 	if (!transport->xprt.resvport)
1322 		port = 0;
1323 	sa = (struct sockaddr_in6 *)&transport->addr;
1324 	myaddr.sin6_addr = sa->sin6_addr;
1325 	do {
1326 		myaddr.sin6_port = htons(port);
1327 		err = kernel_bind(sock, (struct sockaddr *) &myaddr,
1328 						sizeof(myaddr));
1329 		if (!transport->xprt.resvport)
1330 			break;
1331 		if (err == 0) {
1332 			transport->port = port;
1333 			break;
1334 		}
1335 		if (port <= xprt_min_resvport)
1336 			port = xprt_max_resvport;
1337 		else
1338 			port--;
1339 	} while (err == -EADDRINUSE && port != transport->port);
1340 	dprintk("RPC:       xs_bind6 "NIP6_FMT":%u: %s (%d)\n",
1341 		NIP6(myaddr.sin6_addr), port, err ? "failed" : "ok", err);
1342 	return err;
1343 }
1344 
1345 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1346 static struct lock_class_key xs_key[2];
1347 static struct lock_class_key xs_slock_key[2];
1348 
1349 static inline void xs_reclassify_socket4(struct socket *sock)
1350 {
1351 	struct sock *sk = sock->sk;
1352 
1353 	BUG_ON(sock_owned_by_user(sk));
1354 	sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1355 		&xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1356 }
1357 
1358 static inline void xs_reclassify_socket6(struct socket *sock)
1359 {
1360 	struct sock *sk = sock->sk;
1361 
1362 	BUG_ON(sock_owned_by_user(sk));
1363 	sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1364 		&xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1365 }
1366 #else
1367 static inline void xs_reclassify_socket4(struct socket *sock)
1368 {
1369 }
1370 
1371 static inline void xs_reclassify_socket6(struct socket *sock)
1372 {
1373 }
1374 #endif
1375 
1376 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
1377 {
1378 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1379 
1380 	if (!transport->inet) {
1381 		struct sock *sk = sock->sk;
1382 
1383 		write_lock_bh(&sk->sk_callback_lock);
1384 
1385 		sk->sk_user_data = xprt;
1386 		transport->old_data_ready = sk->sk_data_ready;
1387 		transport->old_state_change = sk->sk_state_change;
1388 		transport->old_write_space = sk->sk_write_space;
1389 		sk->sk_data_ready = xs_udp_data_ready;
1390 		sk->sk_write_space = xs_udp_write_space;
1391 		sk->sk_no_check = UDP_CSUM_NORCV;
1392 		sk->sk_allocation = GFP_ATOMIC;
1393 
1394 		xprt_set_connected(xprt);
1395 
1396 		/* Reset to new socket */
1397 		transport->sock = sock;
1398 		transport->inet = sk;
1399 
1400 		write_unlock_bh(&sk->sk_callback_lock);
1401 	}
1402 	xs_udp_do_set_buffer_size(xprt);
1403 }
1404 
1405 /**
1406  * xs_udp_connect_worker4 - set up a UDP socket
1407  * @work: RPC transport to connect
1408  *
1409  * Invoked by a work queue tasklet.
1410  */
1411 static void xs_udp_connect_worker4(struct work_struct *work)
1412 {
1413 	struct sock_xprt *transport =
1414 		container_of(work, struct sock_xprt, connect_worker.work);
1415 	struct rpc_xprt *xprt = &transport->xprt;
1416 	struct socket *sock = transport->sock;
1417 	int err, status = -EIO;
1418 
1419 	if (xprt->shutdown || !xprt_bound(xprt))
1420 		goto out;
1421 
1422 	/* Start by resetting any existing state */
1423 	xs_close(xprt);
1424 
1425 	if ((err = sock_create_kern(PF_INET, SOCK_DGRAM, IPPROTO_UDP, &sock)) < 0) {
1426 		dprintk("RPC:       can't create UDP transport socket (%d).\n", -err);
1427 		goto out;
1428 	}
1429 	xs_reclassify_socket4(sock);
1430 
1431 	if (xs_bind4(transport, sock)) {
1432 		sock_release(sock);
1433 		goto out;
1434 	}
1435 
1436 	dprintk("RPC:       worker connecting xprt %p to address: %s\n",
1437 			xprt, xprt->address_strings[RPC_DISPLAY_ALL]);
1438 
1439 	xs_udp_finish_connecting(xprt, sock);
1440 	status = 0;
1441 out:
1442 	xprt_wake_pending_tasks(xprt, status);
1443 	xprt_clear_connecting(xprt);
1444 }
1445 
1446 /**
1447  * xs_udp_connect_worker6 - set up a UDP socket
1448  * @work: RPC transport to connect
1449  *
1450  * Invoked by a work queue tasklet.
1451  */
1452 static void xs_udp_connect_worker6(struct work_struct *work)
1453 {
1454 	struct sock_xprt *transport =
1455 		container_of(work, struct sock_xprt, connect_worker.work);
1456 	struct rpc_xprt *xprt = &transport->xprt;
1457 	struct socket *sock = transport->sock;
1458 	int err, status = -EIO;
1459 
1460 	if (xprt->shutdown || !xprt_bound(xprt))
1461 		goto out;
1462 
1463 	/* Start by resetting any existing state */
1464 	xs_close(xprt);
1465 
1466 	if ((err = sock_create_kern(PF_INET6, SOCK_DGRAM, IPPROTO_UDP, &sock)) < 0) {
1467 		dprintk("RPC:       can't create UDP transport socket (%d).\n", -err);
1468 		goto out;
1469 	}
1470 	xs_reclassify_socket6(sock);
1471 
1472 	if (xs_bind6(transport, sock) < 0) {
1473 		sock_release(sock);
1474 		goto out;
1475 	}
1476 
1477 	dprintk("RPC:       worker connecting xprt %p to address: %s\n",
1478 			xprt, xprt->address_strings[RPC_DISPLAY_ALL]);
1479 
1480 	xs_udp_finish_connecting(xprt, sock);
1481 	status = 0;
1482 out:
1483 	xprt_wake_pending_tasks(xprt, status);
1484 	xprt_clear_connecting(xprt);
1485 }
1486 
1487 /*
1488  * We need to preserve the port number so the reply cache on the server can
1489  * find our cached RPC replies when we get around to reconnecting.
1490  */
1491 static void xs_tcp_reuse_connection(struct rpc_xprt *xprt)
1492 {
1493 	int result;
1494 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1495 	struct sockaddr any;
1496 
1497 	dprintk("RPC:       disconnecting xprt %p to reuse port\n", xprt);
1498 
1499 	/*
1500 	 * Disconnect the transport socket by doing a connect operation
1501 	 * with AF_UNSPEC.  This should return immediately...
1502 	 */
1503 	memset(&any, 0, sizeof(any));
1504 	any.sa_family = AF_UNSPEC;
1505 	result = kernel_connect(transport->sock, &any, sizeof(any), 0);
1506 	if (result)
1507 		dprintk("RPC:       AF_UNSPEC connect return code %d\n",
1508 				result);
1509 }
1510 
1511 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
1512 {
1513 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1514 
1515 	if (!transport->inet) {
1516 		struct sock *sk = sock->sk;
1517 
1518 		write_lock_bh(&sk->sk_callback_lock);
1519 
1520 		sk->sk_user_data = xprt;
1521 		transport->old_data_ready = sk->sk_data_ready;
1522 		transport->old_state_change = sk->sk_state_change;
1523 		transport->old_write_space = sk->sk_write_space;
1524 		sk->sk_data_ready = xs_tcp_data_ready;
1525 		sk->sk_state_change = xs_tcp_state_change;
1526 		sk->sk_write_space = xs_tcp_write_space;
1527 		sk->sk_allocation = GFP_ATOMIC;
1528 
1529 		/* socket options */
1530 		sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
1531 		sock_reset_flag(sk, SOCK_LINGER);
1532 		tcp_sk(sk)->linger2 = 0;
1533 		tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
1534 
1535 		xprt_clear_connected(xprt);
1536 
1537 		/* Reset to new socket */
1538 		transport->sock = sock;
1539 		transport->inet = sk;
1540 
1541 		write_unlock_bh(&sk->sk_callback_lock);
1542 	}
1543 
1544 	/* Tell the socket layer to start connecting... */
1545 	xprt->stat.connect_count++;
1546 	xprt->stat.connect_start = jiffies;
1547 	return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
1548 }
1549 
1550 /**
1551  * xs_tcp_connect_worker4 - connect a TCP socket to a remote endpoint
1552  * @work: RPC transport to connect
1553  *
1554  * Invoked by a work queue tasklet.
1555  */
1556 static void xs_tcp_connect_worker4(struct work_struct *work)
1557 {
1558 	struct sock_xprt *transport =
1559 		container_of(work, struct sock_xprt, connect_worker.work);
1560 	struct rpc_xprt *xprt = &transport->xprt;
1561 	struct socket *sock = transport->sock;
1562 	int err, status = -EIO;
1563 
1564 	if (xprt->shutdown || !xprt_bound(xprt))
1565 		goto out;
1566 
1567 	if (!sock) {
1568 		/* start from scratch */
1569 		if ((err = sock_create_kern(PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock)) < 0) {
1570 			dprintk("RPC:       can't create TCP transport socket (%d).\n", -err);
1571 			goto out;
1572 		}
1573 		xs_reclassify_socket4(sock);
1574 
1575 		if (xs_bind4(transport, sock) < 0) {
1576 			sock_release(sock);
1577 			goto out;
1578 		}
1579 	} else
1580 		/* "close" the socket, preserving the local port */
1581 		xs_tcp_reuse_connection(xprt);
1582 
1583 	dprintk("RPC:       worker connecting xprt %p to address: %s\n",
1584 			xprt, xprt->address_strings[RPC_DISPLAY_ALL]);
1585 
1586 	status = xs_tcp_finish_connecting(xprt, sock);
1587 	dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
1588 			xprt, -status, xprt_connected(xprt),
1589 			sock->sk->sk_state);
1590 	if (status < 0) {
1591 		switch (status) {
1592 			case -EINPROGRESS:
1593 			case -EALREADY:
1594 				goto out_clear;
1595 			case -ECONNREFUSED:
1596 			case -ECONNRESET:
1597 				/* retry with existing socket, after a delay */
1598 				break;
1599 			default:
1600 				/* get rid of existing socket, and retry */
1601 				xs_close(xprt);
1602 				break;
1603 		}
1604 	}
1605 out:
1606 	xprt_wake_pending_tasks(xprt, status);
1607 out_clear:
1608 	xprt_clear_connecting(xprt);
1609 }
1610 
1611 /**
1612  * xs_tcp_connect_worker6 - connect a TCP socket to a remote endpoint
1613  * @work: RPC transport to connect
1614  *
1615  * Invoked by a work queue tasklet.
1616  */
1617 static void xs_tcp_connect_worker6(struct work_struct *work)
1618 {
1619 	struct sock_xprt *transport =
1620 		container_of(work, struct sock_xprt, connect_worker.work);
1621 	struct rpc_xprt *xprt = &transport->xprt;
1622 	struct socket *sock = transport->sock;
1623 	int err, status = -EIO;
1624 
1625 	if (xprt->shutdown || !xprt_bound(xprt))
1626 		goto out;
1627 
1628 	if (!sock) {
1629 		/* start from scratch */
1630 		if ((err = sock_create_kern(PF_INET6, SOCK_STREAM, IPPROTO_TCP, &sock)) < 0) {
1631 			dprintk("RPC:       can't create TCP transport socket (%d).\n", -err);
1632 			goto out;
1633 		}
1634 		xs_reclassify_socket6(sock);
1635 
1636 		if (xs_bind6(transport, sock) < 0) {
1637 			sock_release(sock);
1638 			goto out;
1639 		}
1640 	} else
1641 		/* "close" the socket, preserving the local port */
1642 		xs_tcp_reuse_connection(xprt);
1643 
1644 	dprintk("RPC:       worker connecting xprt %p to address: %s\n",
1645 			xprt, xprt->address_strings[RPC_DISPLAY_ALL]);
1646 
1647 	status = xs_tcp_finish_connecting(xprt, sock);
1648 	dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
1649 			xprt, -status, xprt_connected(xprt), sock->sk->sk_state);
1650 	if (status < 0) {
1651 		switch (status) {
1652 			case -EINPROGRESS:
1653 			case -EALREADY:
1654 				goto out_clear;
1655 			case -ECONNREFUSED:
1656 			case -ECONNRESET:
1657 				/* retry with existing socket, after a delay */
1658 				break;
1659 			default:
1660 				/* get rid of existing socket, and retry */
1661 				xs_close(xprt);
1662 				break;
1663 		}
1664 	}
1665 out:
1666 	xprt_wake_pending_tasks(xprt, status);
1667 out_clear:
1668 	xprt_clear_connecting(xprt);
1669 }
1670 
1671 /**
1672  * xs_connect - connect a socket to a remote endpoint
1673  * @task: address of RPC task that manages state of connect request
1674  *
1675  * TCP: If the remote end dropped the connection, delay reconnecting.
1676  *
1677  * UDP socket connects are synchronous, but we use a work queue anyway
1678  * to guarantee that even unprivileged user processes can set up a
1679  * socket on a privileged port.
1680  *
1681  * If a UDP socket connect fails, the delay behavior here prevents
1682  * retry floods (hard mounts).
1683  */
1684 static void xs_connect(struct rpc_task *task)
1685 {
1686 	struct rpc_xprt *xprt = task->tk_xprt;
1687 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1688 
1689 	if (xprt_test_and_set_connecting(xprt))
1690 		return;
1691 
1692 	if (transport->sock != NULL) {
1693 		dprintk("RPC:       xs_connect delayed xprt %p for %lu "
1694 				"seconds\n",
1695 				xprt, xprt->reestablish_timeout / HZ);
1696 		queue_delayed_work(rpciod_workqueue,
1697 				   &transport->connect_worker,
1698 				   xprt->reestablish_timeout);
1699 		xprt->reestablish_timeout <<= 1;
1700 		if (xprt->reestablish_timeout > XS_TCP_MAX_REEST_TO)
1701 			xprt->reestablish_timeout = XS_TCP_MAX_REEST_TO;
1702 	} else {
1703 		dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
1704 		queue_delayed_work(rpciod_workqueue,
1705 				   &transport->connect_worker, 0);
1706 	}
1707 }
1708 
1709 /**
1710  * xs_udp_print_stats - display UDP socket-specifc stats
1711  * @xprt: rpc_xprt struct containing statistics
1712  * @seq: output file
1713  *
1714  */
1715 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
1716 {
1717 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1718 
1719 	seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %Lu %Lu\n",
1720 			transport->port,
1721 			xprt->stat.bind_count,
1722 			xprt->stat.sends,
1723 			xprt->stat.recvs,
1724 			xprt->stat.bad_xids,
1725 			xprt->stat.req_u,
1726 			xprt->stat.bklog_u);
1727 }
1728 
1729 /**
1730  * xs_tcp_print_stats - display TCP socket-specifc stats
1731  * @xprt: rpc_xprt struct containing statistics
1732  * @seq: output file
1733  *
1734  */
1735 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
1736 {
1737 	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1738 	long idle_time = 0;
1739 
1740 	if (xprt_connected(xprt))
1741 		idle_time = (long)(jiffies - xprt->last_used) / HZ;
1742 
1743 	seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu %Lu %Lu\n",
1744 			transport->port,
1745 			xprt->stat.bind_count,
1746 			xprt->stat.connect_count,
1747 			xprt->stat.connect_time,
1748 			idle_time,
1749 			xprt->stat.sends,
1750 			xprt->stat.recvs,
1751 			xprt->stat.bad_xids,
1752 			xprt->stat.req_u,
1753 			xprt->stat.bklog_u);
1754 }
1755 
1756 static struct rpc_xprt_ops xs_udp_ops = {
1757 	.set_buffer_size	= xs_udp_set_buffer_size,
1758 	.reserve_xprt		= xprt_reserve_xprt_cong,
1759 	.release_xprt		= xprt_release_xprt_cong,
1760 	.rpcbind		= rpcb_getport_async,
1761 	.set_port		= xs_set_port,
1762 	.connect		= xs_connect,
1763 	.buf_alloc		= rpc_malloc,
1764 	.buf_free		= rpc_free,
1765 	.send_request		= xs_udp_send_request,
1766 	.set_retrans_timeout	= xprt_set_retrans_timeout_rtt,
1767 	.timer			= xs_udp_timer,
1768 	.release_request	= xprt_release_rqst_cong,
1769 	.close			= xs_close,
1770 	.destroy		= xs_destroy,
1771 	.print_stats		= xs_udp_print_stats,
1772 };
1773 
1774 static struct rpc_xprt_ops xs_tcp_ops = {
1775 	.reserve_xprt		= xprt_reserve_xprt,
1776 	.release_xprt		= xs_tcp_release_xprt,
1777 	.rpcbind		= rpcb_getport_async,
1778 	.set_port		= xs_set_port,
1779 	.connect		= xs_connect,
1780 	.buf_alloc		= rpc_malloc,
1781 	.buf_free		= rpc_free,
1782 	.send_request		= xs_tcp_send_request,
1783 	.set_retrans_timeout	= xprt_set_retrans_timeout_def,
1784 	.close			= xs_close,
1785 	.destroy		= xs_destroy,
1786 	.print_stats		= xs_tcp_print_stats,
1787 };
1788 
1789 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
1790 				      unsigned int slot_table_size)
1791 {
1792 	struct rpc_xprt *xprt;
1793 	struct sock_xprt *new;
1794 
1795 	if (args->addrlen > sizeof(xprt->addr)) {
1796 		dprintk("RPC:       xs_setup_xprt: address too large\n");
1797 		return ERR_PTR(-EBADF);
1798 	}
1799 
1800 	new = kzalloc(sizeof(*new), GFP_KERNEL);
1801 	if (new == NULL) {
1802 		dprintk("RPC:       xs_setup_xprt: couldn't allocate "
1803 				"rpc_xprt\n");
1804 		return ERR_PTR(-ENOMEM);
1805 	}
1806 	xprt = &new->xprt;
1807 
1808 	xprt->max_reqs = slot_table_size;
1809 	xprt->slot = kcalloc(xprt->max_reqs, sizeof(struct rpc_rqst), GFP_KERNEL);
1810 	if (xprt->slot == NULL) {
1811 		kfree(xprt);
1812 		dprintk("RPC:       xs_setup_xprt: couldn't allocate slot "
1813 				"table\n");
1814 		return ERR_PTR(-ENOMEM);
1815 	}
1816 
1817 	memcpy(&xprt->addr, args->dstaddr, args->addrlen);
1818 	xprt->addrlen = args->addrlen;
1819 	if (args->srcaddr)
1820 		memcpy(&new->addr, args->srcaddr, args->addrlen);
1821 	new->port = xs_get_random_port();
1822 
1823 	return xprt;
1824 }
1825 
1826 /**
1827  * xs_setup_udp - Set up transport to use a UDP socket
1828  * @args: rpc transport creation arguments
1829  *
1830  */
1831 struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
1832 {
1833 	struct sockaddr *addr = args->dstaddr;
1834 	struct rpc_xprt *xprt;
1835 	struct sock_xprt *transport;
1836 
1837 	xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries);
1838 	if (IS_ERR(xprt))
1839 		return xprt;
1840 	transport = container_of(xprt, struct sock_xprt, xprt);
1841 
1842 	xprt->prot = IPPROTO_UDP;
1843 	xprt->tsh_size = 0;
1844 	/* XXX: header size can vary due to auth type, IPv6, etc. */
1845 	xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
1846 
1847 	xprt->bind_timeout = XS_BIND_TO;
1848 	xprt->connect_timeout = XS_UDP_CONN_TO;
1849 	xprt->reestablish_timeout = XS_UDP_REEST_TO;
1850 	xprt->idle_timeout = XS_IDLE_DISC_TO;
1851 
1852 	xprt->ops = &xs_udp_ops;
1853 
1854 	if (args->timeout)
1855 		xprt->timeout = *args->timeout;
1856 	else
1857 		xprt_set_timeout(&xprt->timeout, 5, 5 * HZ);
1858 
1859 	switch (addr->sa_family) {
1860 	case AF_INET:
1861 		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
1862 			xprt_set_bound(xprt);
1863 
1864 		INIT_DELAYED_WORK(&transport->connect_worker,
1865 					xs_udp_connect_worker4);
1866 		xs_format_ipv4_peer_addresses(xprt);
1867 		break;
1868 	case AF_INET6:
1869 		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
1870 			xprt_set_bound(xprt);
1871 
1872 		INIT_DELAYED_WORK(&transport->connect_worker,
1873 					xs_udp_connect_worker6);
1874 		xs_format_ipv6_peer_addresses(xprt);
1875 		break;
1876 	default:
1877 		kfree(xprt);
1878 		return ERR_PTR(-EAFNOSUPPORT);
1879 	}
1880 
1881 	dprintk("RPC:       set up transport to address %s\n",
1882 			xprt->address_strings[RPC_DISPLAY_ALL]);
1883 
1884 	if (try_module_get(THIS_MODULE))
1885 		return xprt;
1886 
1887 	kfree(xprt->slot);
1888 	kfree(xprt);
1889 	return ERR_PTR(-EINVAL);
1890 }
1891 
1892 /**
1893  * xs_setup_tcp - Set up transport to use a TCP socket
1894  * @args: rpc transport creation arguments
1895  *
1896  */
1897 struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
1898 {
1899 	struct sockaddr *addr = args->dstaddr;
1900 	struct rpc_xprt *xprt;
1901 	struct sock_xprt *transport;
1902 
1903 	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries);
1904 	if (IS_ERR(xprt))
1905 		return xprt;
1906 	transport = container_of(xprt, struct sock_xprt, xprt);
1907 
1908 	xprt->prot = IPPROTO_TCP;
1909 	xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
1910 	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
1911 
1912 	xprt->bind_timeout = XS_BIND_TO;
1913 	xprt->connect_timeout = XS_TCP_CONN_TO;
1914 	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1915 	xprt->idle_timeout = XS_IDLE_DISC_TO;
1916 
1917 	xprt->ops = &xs_tcp_ops;
1918 
1919 	if (args->timeout)
1920 		xprt->timeout = *args->timeout;
1921 	else
1922 		xprt_set_timeout(&xprt->timeout, 2, 60 * HZ);
1923 
1924 	switch (addr->sa_family) {
1925 	case AF_INET:
1926 		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
1927 			xprt_set_bound(xprt);
1928 
1929 		INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_connect_worker4);
1930 		xs_format_ipv4_peer_addresses(xprt);
1931 		break;
1932 	case AF_INET6:
1933 		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
1934 			xprt_set_bound(xprt);
1935 
1936 		INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_connect_worker6);
1937 		xs_format_ipv6_peer_addresses(xprt);
1938 		break;
1939 	default:
1940 		kfree(xprt);
1941 		return ERR_PTR(-EAFNOSUPPORT);
1942 	}
1943 
1944 	dprintk("RPC:       set up transport to address %s\n",
1945 			xprt->address_strings[RPC_DISPLAY_ALL]);
1946 
1947 	if (try_module_get(THIS_MODULE))
1948 		return xprt;
1949 
1950 	kfree(xprt->slot);
1951 	kfree(xprt);
1952 	return ERR_PTR(-EINVAL);
1953 }
1954 
1955 static struct xprt_class	xs_udp_transport = {
1956 	.list		= LIST_HEAD_INIT(xs_udp_transport.list),
1957 	.name		= "udp",
1958 	.owner		= THIS_MODULE,
1959 	.ident		= IPPROTO_UDP,
1960 	.setup		= xs_setup_udp,
1961 };
1962 
1963 static struct xprt_class	xs_tcp_transport = {
1964 	.list		= LIST_HEAD_INIT(xs_tcp_transport.list),
1965 	.name		= "tcp",
1966 	.owner		= THIS_MODULE,
1967 	.ident		= IPPROTO_TCP,
1968 	.setup		= xs_setup_tcp,
1969 };
1970 
1971 /**
1972  * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
1973  *
1974  */
1975 int init_socket_xprt(void)
1976 {
1977 #ifdef RPC_DEBUG
1978 	if (!sunrpc_table_header)
1979 		sunrpc_table_header = register_sysctl_table(sunrpc_table);
1980 #endif
1981 
1982 	xprt_register_transport(&xs_udp_transport);
1983 	xprt_register_transport(&xs_tcp_transport);
1984 
1985 	return 0;
1986 }
1987 
1988 /**
1989  * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
1990  *
1991  */
1992 void cleanup_socket_xprt(void)
1993 {
1994 #ifdef RPC_DEBUG
1995 	if (sunrpc_table_header) {
1996 		unregister_sysctl_table(sunrpc_table_header);
1997 		sunrpc_table_header = NULL;
1998 	}
1999 #endif
2000 
2001 	xprt_unregister_transport(&xs_udp_transport);
2002 	xprt_unregister_transport(&xs_tcp_transport);
2003 }
2004