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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 <linux/bvec.h>
51#include <linux/highmem.h>
52#include <linux/uio.h>
53#include <linux/sched/mm.h>
54
55#include <trace/events/sunrpc.h>
56
57#include "socklib.h"
58#include "sunrpc.h"
59
60static void xs_close(struct rpc_xprt *xprt);
61static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock);
62static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
63 struct socket *sock);
64
65/*
66 * xprtsock tunables
67 */
68static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
69static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
70static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
71
72static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
73static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
74
75#define XS_TCP_LINGER_TO (15U * HZ)
76static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
77
78/*
79 * We can register our own files under /proc/sys/sunrpc by
80 * calling register_sysctl_table() again. The files in that
81 * directory become the union of all files registered there.
82 *
83 * We simply need to make sure that we don't collide with
84 * someone else's file names!
85 */
86
87static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
88static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
89static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
90static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
91static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
92
93static struct ctl_table_header *sunrpc_table_header;
94
95static struct xprt_class xs_local_transport;
96static struct xprt_class xs_udp_transport;
97static struct xprt_class xs_tcp_transport;
98static struct xprt_class xs_bc_tcp_transport;
99
100/*
101 * FIXME: changing the UDP slot table size should also resize the UDP
102 * socket buffers for existing UDP transports
103 */
104static struct ctl_table xs_tunables_table[] = {
105 {
106 .procname = "udp_slot_table_entries",
107 .data = &xprt_udp_slot_table_entries,
108 .maxlen = sizeof(unsigned int),
109 .mode = 0644,
110 .proc_handler = proc_dointvec_minmax,
111 .extra1 = &min_slot_table_size,
112 .extra2 = &max_slot_table_size
113 },
114 {
115 .procname = "tcp_slot_table_entries",
116 .data = &xprt_tcp_slot_table_entries,
117 .maxlen = sizeof(unsigned int),
118 .mode = 0644,
119 .proc_handler = proc_dointvec_minmax,
120 .extra1 = &min_slot_table_size,
121 .extra2 = &max_slot_table_size
122 },
123 {
124 .procname = "tcp_max_slot_table_entries",
125 .data = &xprt_max_tcp_slot_table_entries,
126 .maxlen = sizeof(unsigned int),
127 .mode = 0644,
128 .proc_handler = proc_dointvec_minmax,
129 .extra1 = &min_slot_table_size,
130 .extra2 = &max_tcp_slot_table_limit
131 },
132 {
133 .procname = "min_resvport",
134 .data = &xprt_min_resvport,
135 .maxlen = sizeof(unsigned int),
136 .mode = 0644,
137 .proc_handler = proc_dointvec_minmax,
138 .extra1 = &xprt_min_resvport_limit,
139 .extra2 = &xprt_max_resvport_limit
140 },
141 {
142 .procname = "max_resvport",
143 .data = &xprt_max_resvport,
144 .maxlen = sizeof(unsigned int),
145 .mode = 0644,
146 .proc_handler = proc_dointvec_minmax,
147 .extra1 = &xprt_min_resvport_limit,
148 .extra2 = &xprt_max_resvport_limit
149 },
150 {
151 .procname = "tcp_fin_timeout",
152 .data = &xs_tcp_fin_timeout,
153 .maxlen = sizeof(xs_tcp_fin_timeout),
154 .mode = 0644,
155 .proc_handler = proc_dointvec_jiffies,
156 },
157 { },
158};
159
160static struct ctl_table sunrpc_table[] = {
161 {
162 .procname = "sunrpc",
163 .mode = 0555,
164 .child = xs_tunables_table
165 },
166 { },
167};
168
169/*
170 * Wait duration for a reply from the RPC portmapper.
171 */
172#define XS_BIND_TO (60U * HZ)
173
174/*
175 * Delay if a UDP socket connect error occurs. This is most likely some
176 * kind of resource problem on the local host.
177 */
178#define XS_UDP_REEST_TO (2U * HZ)
179
180/*
181 * The reestablish timeout allows clients to delay for a bit before attempting
182 * to reconnect to a server that just dropped our connection.
183 *
184 * We implement an exponential backoff when trying to reestablish a TCP
185 * transport connection with the server. Some servers like to drop a TCP
186 * connection when they are overworked, so we start with a short timeout and
187 * increase over time if the server is down or not responding.
188 */
189#define XS_TCP_INIT_REEST_TO (3U * HZ)
190
191/*
192 * TCP idle timeout; client drops the transport socket if it is idle
193 * for this long. Note that we also timeout UDP sockets to prevent
194 * holding port numbers when there is no RPC traffic.
195 */
196#define XS_IDLE_DISC_TO (5U * 60 * HZ)
197
198#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
199# undef RPC_DEBUG_DATA
200# define RPCDBG_FACILITY RPCDBG_TRANS
201#endif
202
203#ifdef RPC_DEBUG_DATA
204static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
205{
206 u8 *buf = (u8 *) packet;
207 int j;
208
209 dprintk("RPC: %s\n", msg);
210 for (j = 0; j < count && j < 128; j += 4) {
211 if (!(j & 31)) {
212 if (j)
213 dprintk("\n");
214 dprintk("0x%04x ", j);
215 }
216 dprintk("%02x%02x%02x%02x ",
217 buf[j], buf[j+1], buf[j+2], buf[j+3]);
218 }
219 dprintk("\n");
220}
221#else
222static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
223{
224 /* NOP */
225}
226#endif
227
228static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
229{
230 return (struct rpc_xprt *) sk->sk_user_data;
231}
232
233static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
234{
235 return (struct sockaddr *) &xprt->addr;
236}
237
238static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
239{
240 return (struct sockaddr_un *) &xprt->addr;
241}
242
243static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
244{
245 return (struct sockaddr_in *) &xprt->addr;
246}
247
248static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
249{
250 return (struct sockaddr_in6 *) &xprt->addr;
251}
252
253static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
254{
255 struct sockaddr *sap = xs_addr(xprt);
256 struct sockaddr_in6 *sin6;
257 struct sockaddr_in *sin;
258 struct sockaddr_un *sun;
259 char buf[128];
260
261 switch (sap->sa_family) {
262 case AF_LOCAL:
263 sun = xs_addr_un(xprt);
264 strscpy(buf, sun->sun_path, sizeof(buf));
265 xprt->address_strings[RPC_DISPLAY_ADDR] =
266 kstrdup(buf, GFP_KERNEL);
267 break;
268 case AF_INET:
269 (void)rpc_ntop(sap, buf, sizeof(buf));
270 xprt->address_strings[RPC_DISPLAY_ADDR] =
271 kstrdup(buf, GFP_KERNEL);
272 sin = xs_addr_in(xprt);
273 snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
274 break;
275 case AF_INET6:
276 (void)rpc_ntop(sap, buf, sizeof(buf));
277 xprt->address_strings[RPC_DISPLAY_ADDR] =
278 kstrdup(buf, GFP_KERNEL);
279 sin6 = xs_addr_in6(xprt);
280 snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
281 break;
282 default:
283 BUG();
284 }
285
286 xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
287}
288
289static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
290{
291 struct sockaddr *sap = xs_addr(xprt);
292 char buf[128];
293
294 snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
295 xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
296
297 snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
298 xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
299}
300
301static void xs_format_peer_addresses(struct rpc_xprt *xprt,
302 const char *protocol,
303 const char *netid)
304{
305 xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
306 xprt->address_strings[RPC_DISPLAY_NETID] = netid;
307 xs_format_common_peer_addresses(xprt);
308 xs_format_common_peer_ports(xprt);
309}
310
311static void xs_update_peer_port(struct rpc_xprt *xprt)
312{
313 kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
314 kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
315
316 xs_format_common_peer_ports(xprt);
317}
318
319static void xs_free_peer_addresses(struct rpc_xprt *xprt)
320{
321 unsigned int i;
322
323 for (i = 0; i < RPC_DISPLAY_MAX; i++)
324 switch (i) {
325 case RPC_DISPLAY_PROTO:
326 case RPC_DISPLAY_NETID:
327 continue;
328 default:
329 kfree(xprt->address_strings[i]);
330 }
331}
332
333static size_t
334xs_alloc_sparse_pages(struct xdr_buf *buf, size_t want, gfp_t gfp)
335{
336 size_t i,n;
337
338 if (!want || !(buf->flags & XDRBUF_SPARSE_PAGES))
339 return want;
340 n = (buf->page_base + want + PAGE_SIZE - 1) >> PAGE_SHIFT;
341 for (i = 0; i < n; i++) {
342 if (buf->pages[i])
343 continue;
344 buf->bvec[i].bv_page = buf->pages[i] = alloc_page(gfp);
345 if (!buf->pages[i]) {
346 i *= PAGE_SIZE;
347 return i > buf->page_base ? i - buf->page_base : 0;
348 }
349 }
350 return want;
351}
352
353static ssize_t
354xs_sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags, size_t seek)
355{
356 ssize_t ret;
357 if (seek != 0)
358 iov_iter_advance(&msg->msg_iter, seek);
359 ret = sock_recvmsg(sock, msg, flags);
360 return ret > 0 ? ret + seek : ret;
361}
362
363static ssize_t
364xs_read_kvec(struct socket *sock, struct msghdr *msg, int flags,
365 struct kvec *kvec, size_t count, size_t seek)
366{
367 iov_iter_kvec(&msg->msg_iter, ITER_DEST, kvec, 1, count);
368 return xs_sock_recvmsg(sock, msg, flags, seek);
369}
370
371static ssize_t
372xs_read_bvec(struct socket *sock, struct msghdr *msg, int flags,
373 struct bio_vec *bvec, unsigned long nr, size_t count,
374 size_t seek)
375{
376 iov_iter_bvec(&msg->msg_iter, ITER_DEST, bvec, nr, count);
377 return xs_sock_recvmsg(sock, msg, flags, seek);
378}
379
380static ssize_t
381xs_read_discard(struct socket *sock, struct msghdr *msg, int flags,
382 size_t count)
383{
384 iov_iter_discard(&msg->msg_iter, ITER_DEST, count);
385 return sock_recvmsg(sock, msg, flags);
386}
387
388#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
389static void
390xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
391{
392 struct bvec_iter bi = {
393 .bi_size = count,
394 };
395 struct bio_vec bv;
396
397 bvec_iter_advance(bvec, &bi, seek & PAGE_MASK);
398 for_each_bvec(bv, bvec, bi, bi)
399 flush_dcache_page(bv.bv_page);
400}
401#else
402static inline void
403xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
404{
405}
406#endif
407
408static ssize_t
409xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags,
410 struct xdr_buf *buf, size_t count, size_t seek, size_t *read)
411{
412 size_t want, seek_init = seek, offset = 0;
413 ssize_t ret;
414
415 want = min_t(size_t, count, buf->head[0].iov_len);
416 if (seek < want) {
417 ret = xs_read_kvec(sock, msg, flags, &buf->head[0], want, seek);
418 if (ret <= 0)
419 goto sock_err;
420 offset += ret;
421 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
422 goto out;
423 if (ret != want)
424 goto out;
425 seek = 0;
426 } else {
427 seek -= want;
428 offset += want;
429 }
430
431 want = xs_alloc_sparse_pages(
432 buf, min_t(size_t, count - offset, buf->page_len),
433 GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
434 if (seek < want) {
435 ret = xs_read_bvec(sock, msg, flags, buf->bvec,
436 xdr_buf_pagecount(buf),
437 want + buf->page_base,
438 seek + buf->page_base);
439 if (ret <= 0)
440 goto sock_err;
441 xs_flush_bvec(buf->bvec, ret, seek + buf->page_base);
442 ret -= buf->page_base;
443 offset += ret;
444 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
445 goto out;
446 if (ret != want)
447 goto out;
448 seek = 0;
449 } else {
450 seek -= want;
451 offset += want;
452 }
453
454 want = min_t(size_t, count - offset, buf->tail[0].iov_len);
455 if (seek < want) {
456 ret = xs_read_kvec(sock, msg, flags, &buf->tail[0], want, seek);
457 if (ret <= 0)
458 goto sock_err;
459 offset += ret;
460 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
461 goto out;
462 if (ret != want)
463 goto out;
464 } else if (offset < seek_init)
465 offset = seek_init;
466 ret = -EMSGSIZE;
467out:
468 *read = offset - seek_init;
469 return ret;
470sock_err:
471 offset += seek;
472 goto out;
473}
474
475static void
476xs_read_header(struct sock_xprt *transport, struct xdr_buf *buf)
477{
478 if (!transport->recv.copied) {
479 if (buf->head[0].iov_len >= transport->recv.offset)
480 memcpy(buf->head[0].iov_base,
481 &transport->recv.xid,
482 transport->recv.offset);
483 transport->recv.copied = transport->recv.offset;
484 }
485}
486
487static bool
488xs_read_stream_request_done(struct sock_xprt *transport)
489{
490 return transport->recv.fraghdr & cpu_to_be32(RPC_LAST_STREAM_FRAGMENT);
491}
492
493static void
494xs_read_stream_check_eor(struct sock_xprt *transport,
495 struct msghdr *msg)
496{
497 if (xs_read_stream_request_done(transport))
498 msg->msg_flags |= MSG_EOR;
499}
500
501static ssize_t
502xs_read_stream_request(struct sock_xprt *transport, struct msghdr *msg,
503 int flags, struct rpc_rqst *req)
504{
505 struct xdr_buf *buf = &req->rq_private_buf;
506 size_t want, read;
507 ssize_t ret;
508
509 xs_read_header(transport, buf);
510
511 want = transport->recv.len - transport->recv.offset;
512 if (want != 0) {
513 ret = xs_read_xdr_buf(transport->sock, msg, flags, buf,
514 transport->recv.copied + want,
515 transport->recv.copied,
516 &read);
517 transport->recv.offset += read;
518 transport->recv.copied += read;
519 }
520
521 if (transport->recv.offset == transport->recv.len)
522 xs_read_stream_check_eor(transport, msg);
523
524 if (want == 0)
525 return 0;
526
527 switch (ret) {
528 default:
529 break;
530 case -EFAULT:
531 case -EMSGSIZE:
532 msg->msg_flags |= MSG_TRUNC;
533 return read;
534 case 0:
535 return -ESHUTDOWN;
536 }
537 return ret < 0 ? ret : read;
538}
539
540static size_t
541xs_read_stream_headersize(bool isfrag)
542{
543 if (isfrag)
544 return sizeof(__be32);
545 return 3 * sizeof(__be32);
546}
547
548static ssize_t
549xs_read_stream_header(struct sock_xprt *transport, struct msghdr *msg,
550 int flags, size_t want, size_t seek)
551{
552 struct kvec kvec = {
553 .iov_base = &transport->recv.fraghdr,
554 .iov_len = want,
555 };
556 return xs_read_kvec(transport->sock, msg, flags, &kvec, want, seek);
557}
558
559#if defined(CONFIG_SUNRPC_BACKCHANNEL)
560static ssize_t
561xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
562{
563 struct rpc_xprt *xprt = &transport->xprt;
564 struct rpc_rqst *req;
565 ssize_t ret;
566
567 /* Is this transport associated with the backchannel? */
568 if (!xprt->bc_serv)
569 return -ESHUTDOWN;
570
571 /* Look up and lock the request corresponding to the given XID */
572 req = xprt_lookup_bc_request(xprt, transport->recv.xid);
573 if (!req) {
574 printk(KERN_WARNING "Callback slot table overflowed\n");
575 return -ESHUTDOWN;
576 }
577 if (transport->recv.copied && !req->rq_private_buf.len)
578 return -ESHUTDOWN;
579
580 ret = xs_read_stream_request(transport, msg, flags, req);
581 if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
582 xprt_complete_bc_request(req, transport->recv.copied);
583 else
584 req->rq_private_buf.len = transport->recv.copied;
585
586 return ret;
587}
588#else /* CONFIG_SUNRPC_BACKCHANNEL */
589static ssize_t
590xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
591{
592 return -ESHUTDOWN;
593}
594#endif /* CONFIG_SUNRPC_BACKCHANNEL */
595
596static ssize_t
597xs_read_stream_reply(struct sock_xprt *transport, struct msghdr *msg, int flags)
598{
599 struct rpc_xprt *xprt = &transport->xprt;
600 struct rpc_rqst *req;
601 ssize_t ret = 0;
602
603 /* Look up and lock the request corresponding to the given XID */
604 spin_lock(&xprt->queue_lock);
605 req = xprt_lookup_rqst(xprt, transport->recv.xid);
606 if (!req || (transport->recv.copied && !req->rq_private_buf.len)) {
607 msg->msg_flags |= MSG_TRUNC;
608 goto out;
609 }
610 xprt_pin_rqst(req);
611 spin_unlock(&xprt->queue_lock);
612
613 ret = xs_read_stream_request(transport, msg, flags, req);
614
615 spin_lock(&xprt->queue_lock);
616 if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
617 xprt_complete_rqst(req->rq_task, transport->recv.copied);
618 else
619 req->rq_private_buf.len = transport->recv.copied;
620 xprt_unpin_rqst(req);
621out:
622 spin_unlock(&xprt->queue_lock);
623 return ret;
624}
625
626static ssize_t
627xs_read_stream(struct sock_xprt *transport, int flags)
628{
629 struct msghdr msg = { 0 };
630 size_t want, read = 0;
631 ssize_t ret = 0;
632
633 if (transport->recv.len == 0) {
634 want = xs_read_stream_headersize(transport->recv.copied != 0);
635 ret = xs_read_stream_header(transport, &msg, flags, want,
636 transport->recv.offset);
637 if (ret <= 0)
638 goto out_err;
639 transport->recv.offset = ret;
640 if (transport->recv.offset != want)
641 return transport->recv.offset;
642 transport->recv.len = be32_to_cpu(transport->recv.fraghdr) &
643 RPC_FRAGMENT_SIZE_MASK;
644 transport->recv.offset -= sizeof(transport->recv.fraghdr);
645 read = ret;
646 }
647
648 switch (be32_to_cpu(transport->recv.calldir)) {
649 default:
650 msg.msg_flags |= MSG_TRUNC;
651 break;
652 case RPC_CALL:
653 ret = xs_read_stream_call(transport, &msg, flags);
654 break;
655 case RPC_REPLY:
656 ret = xs_read_stream_reply(transport, &msg, flags);
657 }
658 if (msg.msg_flags & MSG_TRUNC) {
659 transport->recv.calldir = cpu_to_be32(-1);
660 transport->recv.copied = -1;
661 }
662 if (ret < 0)
663 goto out_err;
664 read += ret;
665 if (transport->recv.offset < transport->recv.len) {
666 if (!(msg.msg_flags & MSG_TRUNC))
667 return read;
668 msg.msg_flags = 0;
669 ret = xs_read_discard(transport->sock, &msg, flags,
670 transport->recv.len - transport->recv.offset);
671 if (ret <= 0)
672 goto out_err;
673 transport->recv.offset += ret;
674 read += ret;
675 if (transport->recv.offset != transport->recv.len)
676 return read;
677 }
678 if (xs_read_stream_request_done(transport)) {
679 trace_xs_stream_read_request(transport);
680 transport->recv.copied = 0;
681 }
682 transport->recv.offset = 0;
683 transport->recv.len = 0;
684 return read;
685out_err:
686 return ret != 0 ? ret : -ESHUTDOWN;
687}
688
689static __poll_t xs_poll_socket(struct sock_xprt *transport)
690{
691 return transport->sock->ops->poll(transport->file, transport->sock,
692 NULL);
693}
694
695static bool xs_poll_socket_readable(struct sock_xprt *transport)
696{
697 __poll_t events = xs_poll_socket(transport);
698
699 return (events & (EPOLLIN | EPOLLRDNORM)) && !(events & EPOLLRDHUP);
700}
701
702static void xs_poll_check_readable(struct sock_xprt *transport)
703{
704
705 clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
706 if (!xs_poll_socket_readable(transport))
707 return;
708 if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
709 queue_work(xprtiod_workqueue, &transport->recv_worker);
710}
711
712static void xs_stream_data_receive(struct sock_xprt *transport)
713{
714 size_t read = 0;
715 ssize_t ret = 0;
716
717 mutex_lock(&transport->recv_mutex);
718 if (transport->sock == NULL)
719 goto out;
720 for (;;) {
721 ret = xs_read_stream(transport, MSG_DONTWAIT);
722 if (ret < 0)
723 break;
724 read += ret;
725 cond_resched();
726 }
727 if (ret == -ESHUTDOWN)
728 kernel_sock_shutdown(transport->sock, SHUT_RDWR);
729 else
730 xs_poll_check_readable(transport);
731out:
732 mutex_unlock(&transport->recv_mutex);
733 trace_xs_stream_read_data(&transport->xprt, ret, read);
734}
735
736static void xs_stream_data_receive_workfn(struct work_struct *work)
737{
738 struct sock_xprt *transport =
739 container_of(work, struct sock_xprt, recv_worker);
740 unsigned int pflags = memalloc_nofs_save();
741
742 xs_stream_data_receive(transport);
743 memalloc_nofs_restore(pflags);
744}
745
746static void
747xs_stream_reset_connect(struct sock_xprt *transport)
748{
749 transport->recv.offset = 0;
750 transport->recv.len = 0;
751 transport->recv.copied = 0;
752 transport->xmit.offset = 0;
753}
754
755static void
756xs_stream_start_connect(struct sock_xprt *transport)
757{
758 transport->xprt.stat.connect_count++;
759 transport->xprt.stat.connect_start = jiffies;
760}
761
762#define XS_SENDMSG_FLAGS (MSG_DONTWAIT | MSG_NOSIGNAL)
763
764/**
765 * xs_nospace - handle transmit was incomplete
766 * @req: pointer to RPC request
767 * @transport: pointer to struct sock_xprt
768 *
769 */
770static int xs_nospace(struct rpc_rqst *req, struct sock_xprt *transport)
771{
772 struct rpc_xprt *xprt = &transport->xprt;
773 struct sock *sk = transport->inet;
774 int ret = -EAGAIN;
775
776 trace_rpc_socket_nospace(req, transport);
777
778 /* Protect against races with write_space */
779 spin_lock(&xprt->transport_lock);
780
781 /* Don't race with disconnect */
782 if (xprt_connected(xprt)) {
783 /* wait for more buffer space */
784 set_bit(XPRT_SOCK_NOSPACE, &transport->sock_state);
785 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
786 sk->sk_write_pending++;
787 xprt_wait_for_buffer_space(xprt);
788 } else
789 ret = -ENOTCONN;
790
791 spin_unlock(&xprt->transport_lock);
792 return ret;
793}
794
795static int xs_sock_nospace(struct rpc_rqst *req)
796{
797 struct sock_xprt *transport =
798 container_of(req->rq_xprt, struct sock_xprt, xprt);
799 struct sock *sk = transport->inet;
800 int ret = -EAGAIN;
801
802 lock_sock(sk);
803 if (!sock_writeable(sk))
804 ret = xs_nospace(req, transport);
805 release_sock(sk);
806 return ret;
807}
808
809static int xs_stream_nospace(struct rpc_rqst *req, bool vm_wait)
810{
811 struct sock_xprt *transport =
812 container_of(req->rq_xprt, struct sock_xprt, xprt);
813 struct sock *sk = transport->inet;
814 int ret = -EAGAIN;
815
816 if (vm_wait)
817 return -ENOBUFS;
818 lock_sock(sk);
819 if (!sk_stream_memory_free(sk))
820 ret = xs_nospace(req, transport);
821 release_sock(sk);
822 return ret;
823}
824
825static int xs_stream_prepare_request(struct rpc_rqst *req, struct xdr_buf *buf)
826{
827 return xdr_alloc_bvec(buf, rpc_task_gfp_mask());
828}
829
830/*
831 * Determine if the previous message in the stream was aborted before it
832 * could complete transmission.
833 */
834static bool
835xs_send_request_was_aborted(struct sock_xprt *transport, struct rpc_rqst *req)
836{
837 return transport->xmit.offset != 0 && req->rq_bytes_sent == 0;
838}
839
840/*
841 * Return the stream record marker field for a record of length < 2^31-1
842 */
843static rpc_fraghdr
844xs_stream_record_marker(struct xdr_buf *xdr)
845{
846 if (!xdr->len)
847 return 0;
848 return cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | (u32)xdr->len);
849}
850
851/**
852 * xs_local_send_request - write an RPC request to an AF_LOCAL socket
853 * @req: pointer to RPC request
854 *
855 * Return values:
856 * 0: The request has been sent
857 * EAGAIN: The socket was blocked, please call again later to
858 * complete the request
859 * ENOTCONN: Caller needs to invoke connect logic then call again
860 * other: Some other error occurred, the request was not sent
861 */
862static int xs_local_send_request(struct rpc_rqst *req)
863{
864 struct rpc_xprt *xprt = req->rq_xprt;
865 struct sock_xprt *transport =
866 container_of(xprt, struct sock_xprt, xprt);
867 struct xdr_buf *xdr = &req->rq_snd_buf;
868 rpc_fraghdr rm = xs_stream_record_marker(xdr);
869 unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
870 struct msghdr msg = {
871 .msg_flags = XS_SENDMSG_FLAGS,
872 };
873 bool vm_wait;
874 unsigned int sent;
875 int status;
876
877 /* Close the stream if the previous transmission was incomplete */
878 if (xs_send_request_was_aborted(transport, req)) {
879 xprt_force_disconnect(xprt);
880 return -ENOTCONN;
881 }
882
883 xs_pktdump("packet data:",
884 req->rq_svec->iov_base, req->rq_svec->iov_len);
885
886 vm_wait = sk_stream_is_writeable(transport->inet) ? true : false;
887
888 req->rq_xtime = ktime_get();
889 status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
890 transport->xmit.offset, rm, &sent);
891 dprintk("RPC: %s(%u) = %d\n",
892 __func__, xdr->len - transport->xmit.offset, status);
893
894 if (likely(sent > 0) || status == 0) {
895 transport->xmit.offset += sent;
896 req->rq_bytes_sent = transport->xmit.offset;
897 if (likely(req->rq_bytes_sent >= msglen)) {
898 req->rq_xmit_bytes_sent += transport->xmit.offset;
899 transport->xmit.offset = 0;
900 return 0;
901 }
902 status = -EAGAIN;
903 vm_wait = false;
904 }
905
906 switch (status) {
907 case -EAGAIN:
908 status = xs_stream_nospace(req, vm_wait);
909 break;
910 default:
911 dprintk("RPC: sendmsg returned unrecognized error %d\n",
912 -status);
913 fallthrough;
914 case -EPIPE:
915 xprt_force_disconnect(xprt);
916 status = -ENOTCONN;
917 }
918
919 return status;
920}
921
922/**
923 * xs_udp_send_request - write an RPC request to a UDP socket
924 * @req: pointer to RPC request
925 *
926 * Return values:
927 * 0: The request has been sent
928 * EAGAIN: The socket was blocked, please call again later to
929 * complete the request
930 * ENOTCONN: Caller needs to invoke connect logic then call again
931 * other: Some other error occurred, the request was not sent
932 */
933static int xs_udp_send_request(struct rpc_rqst *req)
934{
935 struct rpc_xprt *xprt = req->rq_xprt;
936 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
937 struct xdr_buf *xdr = &req->rq_snd_buf;
938 struct msghdr msg = {
939 .msg_name = xs_addr(xprt),
940 .msg_namelen = xprt->addrlen,
941 .msg_flags = XS_SENDMSG_FLAGS,
942 };
943 unsigned int sent;
944 int status;
945
946 xs_pktdump("packet data:",
947 req->rq_svec->iov_base,
948 req->rq_svec->iov_len);
949
950 if (!xprt_bound(xprt))
951 return -ENOTCONN;
952
953 if (!xprt_request_get_cong(xprt, req))
954 return -EBADSLT;
955
956 status = xdr_alloc_bvec(xdr, rpc_task_gfp_mask());
957 if (status < 0)
958 return status;
959 req->rq_xtime = ktime_get();
960 status = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, 0, &sent);
961
962 dprintk("RPC: xs_udp_send_request(%u) = %d\n",
963 xdr->len, status);
964
965 /* firewall is blocking us, don't return -EAGAIN or we end up looping */
966 if (status == -EPERM)
967 goto process_status;
968
969 if (status == -EAGAIN && sock_writeable(transport->inet))
970 status = -ENOBUFS;
971
972 if (sent > 0 || status == 0) {
973 req->rq_xmit_bytes_sent += sent;
974 if (sent >= req->rq_slen)
975 return 0;
976 /* Still some bytes left; set up for a retry later. */
977 status = -EAGAIN;
978 }
979
980process_status:
981 switch (status) {
982 case -ENOTSOCK:
983 status = -ENOTCONN;
984 /* Should we call xs_close() here? */
985 break;
986 case -EAGAIN:
987 status = xs_sock_nospace(req);
988 break;
989 case -ENETUNREACH:
990 case -ENOBUFS:
991 case -EPIPE:
992 case -ECONNREFUSED:
993 case -EPERM:
994 /* When the server has died, an ICMP port unreachable message
995 * prompts ECONNREFUSED. */
996 break;
997 default:
998 dprintk("RPC: sendmsg returned unrecognized error %d\n",
999 -status);
1000 }
1001
1002 return status;
1003}
1004
1005/**
1006 * xs_tcp_send_request - write an RPC request to a TCP socket
1007 * @req: pointer to RPC request
1008 *
1009 * Return values:
1010 * 0: The request has been sent
1011 * EAGAIN: The socket was blocked, please call again later to
1012 * complete the request
1013 * ENOTCONN: Caller needs to invoke connect logic then call again
1014 * other: Some other error occurred, the request was not sent
1015 *
1016 * XXX: In the case of soft timeouts, should we eventually give up
1017 * if sendmsg is not able to make progress?
1018 */
1019static int xs_tcp_send_request(struct rpc_rqst *req)
1020{
1021 struct rpc_xprt *xprt = req->rq_xprt;
1022 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1023 struct xdr_buf *xdr = &req->rq_snd_buf;
1024 rpc_fraghdr rm = xs_stream_record_marker(xdr);
1025 unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
1026 struct msghdr msg = {
1027 .msg_flags = XS_SENDMSG_FLAGS,
1028 };
1029 bool vm_wait;
1030 unsigned int sent;
1031 int status;
1032
1033 /* Close the stream if the previous transmission was incomplete */
1034 if (xs_send_request_was_aborted(transport, req)) {
1035 if (transport->sock != NULL)
1036 kernel_sock_shutdown(transport->sock, SHUT_RDWR);
1037 return -ENOTCONN;
1038 }
1039 if (!transport->inet)
1040 return -ENOTCONN;
1041
1042 xs_pktdump("packet data:",
1043 req->rq_svec->iov_base,
1044 req->rq_svec->iov_len);
1045
1046 if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state))
1047 xs_tcp_set_socket_timeouts(xprt, transport->sock);
1048
1049 xs_set_srcport(transport, transport->sock);
1050
1051 /* Continue transmitting the packet/record. We must be careful
1052 * to cope with writespace callbacks arriving _after_ we have
1053 * called sendmsg(). */
1054 req->rq_xtime = ktime_get();
1055 tcp_sock_set_cork(transport->inet, true);
1056
1057 vm_wait = sk_stream_is_writeable(transport->inet) ? true : false;
1058
1059 do {
1060 status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
1061 transport->xmit.offset, rm, &sent);
1062
1063 dprintk("RPC: xs_tcp_send_request(%u) = %d\n",
1064 xdr->len - transport->xmit.offset, status);
1065
1066 /* If we've sent the entire packet, immediately
1067 * reset the count of bytes sent. */
1068 transport->xmit.offset += sent;
1069 req->rq_bytes_sent = transport->xmit.offset;
1070 if (likely(req->rq_bytes_sent >= msglen)) {
1071 req->rq_xmit_bytes_sent += transport->xmit.offset;
1072 transport->xmit.offset = 0;
1073 if (atomic_long_read(&xprt->xmit_queuelen) == 1)
1074 tcp_sock_set_cork(transport->inet, false);
1075 return 0;
1076 }
1077
1078 WARN_ON_ONCE(sent == 0 && status == 0);
1079
1080 if (sent > 0)
1081 vm_wait = false;
1082
1083 } while (status == 0);
1084
1085 switch (status) {
1086 case -ENOTSOCK:
1087 status = -ENOTCONN;
1088 /* Should we call xs_close() here? */
1089 break;
1090 case -EAGAIN:
1091 status = xs_stream_nospace(req, vm_wait);
1092 break;
1093 case -ECONNRESET:
1094 case -ECONNREFUSED:
1095 case -ENOTCONN:
1096 case -EADDRINUSE:
1097 case -ENOBUFS:
1098 case -EPIPE:
1099 break;
1100 default:
1101 dprintk("RPC: sendmsg returned unrecognized error %d\n",
1102 -status);
1103 }
1104
1105 return status;
1106}
1107
1108static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1109{
1110 transport->old_data_ready = sk->sk_data_ready;
1111 transport->old_state_change = sk->sk_state_change;
1112 transport->old_write_space = sk->sk_write_space;
1113 transport->old_error_report = sk->sk_error_report;
1114}
1115
1116static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1117{
1118 sk->sk_data_ready = transport->old_data_ready;
1119 sk->sk_state_change = transport->old_state_change;
1120 sk->sk_write_space = transport->old_write_space;
1121 sk->sk_error_report = transport->old_error_report;
1122}
1123
1124static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
1125{
1126 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1127
1128 clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1129 clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state);
1130 clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state);
1131 clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state);
1132 clear_bit(XPRT_SOCK_NOSPACE, &transport->sock_state);
1133}
1134
1135static void xs_run_error_worker(struct sock_xprt *transport, unsigned int nr)
1136{
1137 set_bit(nr, &transport->sock_state);
1138 queue_work(xprtiod_workqueue, &transport->error_worker);
1139}
1140
1141static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
1142{
1143 xprt->connect_cookie++;
1144 smp_mb__before_atomic();
1145 clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1146 clear_bit(XPRT_CLOSING, &xprt->state);
1147 xs_sock_reset_state_flags(xprt);
1148 smp_mb__after_atomic();
1149}
1150
1151/**
1152 * xs_error_report - callback to handle TCP socket state errors
1153 * @sk: socket
1154 *
1155 * Note: we don't call sock_error() since there may be a rpc_task
1156 * using the socket, and so we don't want to clear sk->sk_err.
1157 */
1158static void xs_error_report(struct sock *sk)
1159{
1160 struct sock_xprt *transport;
1161 struct rpc_xprt *xprt;
1162
1163 if (!(xprt = xprt_from_sock(sk)))
1164 return;
1165
1166 transport = container_of(xprt, struct sock_xprt, xprt);
1167 transport->xprt_err = -sk->sk_err;
1168 if (transport->xprt_err == 0)
1169 return;
1170 dprintk("RPC: xs_error_report client %p, error=%d...\n",
1171 xprt, -transport->xprt_err);
1172 trace_rpc_socket_error(xprt, sk->sk_socket, transport->xprt_err);
1173
1174 /* barrier ensures xprt_err is set before XPRT_SOCK_WAKE_ERROR */
1175 smp_mb__before_atomic();
1176 xs_run_error_worker(transport, XPRT_SOCK_WAKE_ERROR);
1177}
1178
1179static void xs_reset_transport(struct sock_xprt *transport)
1180{
1181 struct socket *sock = transport->sock;
1182 struct sock *sk = transport->inet;
1183 struct rpc_xprt *xprt = &transport->xprt;
1184 struct file *filp = transport->file;
1185
1186 if (sk == NULL)
1187 return;
1188 /*
1189 * Make sure we're calling this in a context from which it is safe
1190 * to call __fput_sync(). In practice that means rpciod and the
1191 * system workqueue.
1192 */
1193 if (!(current->flags & PF_WQ_WORKER)) {
1194 WARN_ON_ONCE(1);
1195 set_bit(XPRT_CLOSE_WAIT, &xprt->state);
1196 return;
1197 }
1198
1199 if (atomic_read(&transport->xprt.swapper))
1200 sk_clear_memalloc(sk);
1201
1202 kernel_sock_shutdown(sock, SHUT_RDWR);
1203
1204 mutex_lock(&transport->recv_mutex);
1205 lock_sock(sk);
1206 transport->inet = NULL;
1207 transport->sock = NULL;
1208 transport->file = NULL;
1209
1210 sk->sk_user_data = NULL;
1211
1212 xs_restore_old_callbacks(transport, sk);
1213 xprt_clear_connected(xprt);
1214 xs_sock_reset_connection_flags(xprt);
1215 /* Reset stream record info */
1216 xs_stream_reset_connect(transport);
1217 release_sock(sk);
1218 mutex_unlock(&transport->recv_mutex);
1219
1220 trace_rpc_socket_close(xprt, sock);
1221 __fput_sync(filp);
1222
1223 xprt_disconnect_done(xprt);
1224}
1225
1226/**
1227 * xs_close - close a socket
1228 * @xprt: transport
1229 *
1230 * This is used when all requests are complete; ie, no DRC state remains
1231 * on the server we want to save.
1232 *
1233 * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
1234 * xs_reset_transport() zeroing the socket from underneath a writer.
1235 */
1236static void xs_close(struct rpc_xprt *xprt)
1237{
1238 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1239
1240 dprintk("RPC: xs_close xprt %p\n", xprt);
1241
1242 xs_reset_transport(transport);
1243 xprt->reestablish_timeout = 0;
1244}
1245
1246static void xs_inject_disconnect(struct rpc_xprt *xprt)
1247{
1248 dprintk("RPC: injecting transport disconnect on xprt=%p\n",
1249 xprt);
1250 xprt_disconnect_done(xprt);
1251}
1252
1253static void xs_xprt_free(struct rpc_xprt *xprt)
1254{
1255 xs_free_peer_addresses(xprt);
1256 xprt_free(xprt);
1257}
1258
1259/**
1260 * xs_destroy - prepare to shutdown a transport
1261 * @xprt: doomed transport
1262 *
1263 */
1264static void xs_destroy(struct rpc_xprt *xprt)
1265{
1266 struct sock_xprt *transport = container_of(xprt,
1267 struct sock_xprt, xprt);
1268 dprintk("RPC: xs_destroy xprt %p\n", xprt);
1269
1270 cancel_delayed_work_sync(&transport->connect_worker);
1271 xs_close(xprt);
1272 cancel_work_sync(&transport->recv_worker);
1273 cancel_work_sync(&transport->error_worker);
1274 xs_xprt_free(xprt);
1275 module_put(THIS_MODULE);
1276}
1277
1278/**
1279 * xs_udp_data_read_skb - receive callback for UDP sockets
1280 * @xprt: transport
1281 * @sk: socket
1282 * @skb: skbuff
1283 *
1284 */
1285static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
1286 struct sock *sk,
1287 struct sk_buff *skb)
1288{
1289 struct rpc_task *task;
1290 struct rpc_rqst *rovr;
1291 int repsize, copied;
1292 u32 _xid;
1293 __be32 *xp;
1294
1295 repsize = skb->len;
1296 if (repsize < 4) {
1297 dprintk("RPC: impossible RPC reply size %d!\n", repsize);
1298 return;
1299 }
1300
1301 /* Copy the XID from the skb... */
1302 xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
1303 if (xp == NULL)
1304 return;
1305
1306 /* Look up and lock the request corresponding to the given XID */
1307 spin_lock(&xprt->queue_lock);
1308 rovr = xprt_lookup_rqst(xprt, *xp);
1309 if (!rovr)
1310 goto out_unlock;
1311 xprt_pin_rqst(rovr);
1312 xprt_update_rtt(rovr->rq_task);
1313 spin_unlock(&xprt->queue_lock);
1314 task = rovr->rq_task;
1315
1316 if ((copied = rovr->rq_private_buf.buflen) > repsize)
1317 copied = repsize;
1318
1319 /* Suck it into the iovec, verify checksum if not done by hw. */
1320 if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1321 spin_lock(&xprt->queue_lock);
1322 __UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
1323 goto out_unpin;
1324 }
1325
1326
1327 spin_lock(&xprt->transport_lock);
1328 xprt_adjust_cwnd(xprt, task, copied);
1329 spin_unlock(&xprt->transport_lock);
1330 spin_lock(&xprt->queue_lock);
1331 xprt_complete_rqst(task, copied);
1332 __UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
1333out_unpin:
1334 xprt_unpin_rqst(rovr);
1335 out_unlock:
1336 spin_unlock(&xprt->queue_lock);
1337}
1338
1339static void xs_udp_data_receive(struct sock_xprt *transport)
1340{
1341 struct sk_buff *skb;
1342 struct sock *sk;
1343 int err;
1344
1345 mutex_lock(&transport->recv_mutex);
1346 sk = transport->inet;
1347 if (sk == NULL)
1348 goto out;
1349 for (;;) {
1350 skb = skb_recv_udp(sk, MSG_DONTWAIT, &err);
1351 if (skb == NULL)
1352 break;
1353 xs_udp_data_read_skb(&transport->xprt, sk, skb);
1354 consume_skb(skb);
1355 cond_resched();
1356 }
1357 xs_poll_check_readable(transport);
1358out:
1359 mutex_unlock(&transport->recv_mutex);
1360}
1361
1362static void xs_udp_data_receive_workfn(struct work_struct *work)
1363{
1364 struct sock_xprt *transport =
1365 container_of(work, struct sock_xprt, recv_worker);
1366 unsigned int pflags = memalloc_nofs_save();
1367
1368 xs_udp_data_receive(transport);
1369 memalloc_nofs_restore(pflags);
1370}
1371
1372/**
1373 * xs_data_ready - "data ready" callback for sockets
1374 * @sk: socket with data to read
1375 *
1376 */
1377static void xs_data_ready(struct sock *sk)
1378{
1379 struct rpc_xprt *xprt;
1380
1381 xprt = xprt_from_sock(sk);
1382 if (xprt != NULL) {
1383 struct sock_xprt *transport = container_of(xprt,
1384 struct sock_xprt, xprt);
1385
1386 trace_xs_data_ready(xprt);
1387
1388 transport->old_data_ready(sk);
1389 /* Any data means we had a useful conversation, so
1390 * then we don't need to delay the next reconnect
1391 */
1392 if (xprt->reestablish_timeout)
1393 xprt->reestablish_timeout = 0;
1394 if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1395 queue_work(xprtiod_workqueue, &transport->recv_worker);
1396 }
1397}
1398
1399/*
1400 * Helper function to force a TCP close if the server is sending
1401 * junk and/or it has put us in CLOSE_WAIT
1402 */
1403static void xs_tcp_force_close(struct rpc_xprt *xprt)
1404{
1405 xprt_force_disconnect(xprt);
1406}
1407
1408#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1409static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
1410{
1411 return PAGE_SIZE;
1412}
1413#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1414
1415/**
1416 * xs_local_state_change - callback to handle AF_LOCAL socket state changes
1417 * @sk: socket whose state has changed
1418 *
1419 */
1420static void xs_local_state_change(struct sock *sk)
1421{
1422 struct rpc_xprt *xprt;
1423 struct sock_xprt *transport;
1424
1425 if (!(xprt = xprt_from_sock(sk)))
1426 return;
1427 transport = container_of(xprt, struct sock_xprt, xprt);
1428 if (sk->sk_shutdown & SHUTDOWN_MASK) {
1429 clear_bit(XPRT_CONNECTED, &xprt->state);
1430 /* Trigger the socket release */
1431 xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1432 }
1433}
1434
1435/**
1436 * xs_tcp_state_change - callback to handle TCP socket state changes
1437 * @sk: socket whose state has changed
1438 *
1439 */
1440static void xs_tcp_state_change(struct sock *sk)
1441{
1442 struct rpc_xprt *xprt;
1443 struct sock_xprt *transport;
1444
1445 if (!(xprt = xprt_from_sock(sk)))
1446 return;
1447 dprintk("RPC: xs_tcp_state_change client %p...\n", xprt);
1448 dprintk("RPC: state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1449 sk->sk_state, xprt_connected(xprt),
1450 sock_flag(sk, SOCK_DEAD),
1451 sock_flag(sk, SOCK_ZAPPED),
1452 sk->sk_shutdown);
1453
1454 transport = container_of(xprt, struct sock_xprt, xprt);
1455 trace_rpc_socket_state_change(xprt, sk->sk_socket);
1456 switch (sk->sk_state) {
1457 case TCP_ESTABLISHED:
1458 if (!xprt_test_and_set_connected(xprt)) {
1459 xprt->connect_cookie++;
1460 clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
1461 xprt_clear_connecting(xprt);
1462
1463 xprt->stat.connect_count++;
1464 xprt->stat.connect_time += (long)jiffies -
1465 xprt->stat.connect_start;
1466 xs_run_error_worker(transport, XPRT_SOCK_WAKE_PENDING);
1467 }
1468 break;
1469 case TCP_FIN_WAIT1:
1470 /* The client initiated a shutdown of the socket */
1471 xprt->connect_cookie++;
1472 xprt->reestablish_timeout = 0;
1473 set_bit(XPRT_CLOSING, &xprt->state);
1474 smp_mb__before_atomic();
1475 clear_bit(XPRT_CONNECTED, &xprt->state);
1476 clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1477 smp_mb__after_atomic();
1478 break;
1479 case TCP_CLOSE_WAIT:
1480 /* The server initiated a shutdown of the socket */
1481 xprt->connect_cookie++;
1482 clear_bit(XPRT_CONNECTED, &xprt->state);
1483 xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1484 fallthrough;
1485 case TCP_CLOSING:
1486 /*
1487 * If the server closed down the connection, make sure that
1488 * we back off before reconnecting
1489 */
1490 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1491 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1492 break;
1493 case TCP_LAST_ACK:
1494 set_bit(XPRT_CLOSING, &xprt->state);
1495 smp_mb__before_atomic();
1496 clear_bit(XPRT_CONNECTED, &xprt->state);
1497 smp_mb__after_atomic();
1498 break;
1499 case TCP_CLOSE:
1500 if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
1501 &transport->sock_state))
1502 xprt_clear_connecting(xprt);
1503 clear_bit(XPRT_CLOSING, &xprt->state);
1504 /* Trigger the socket release */
1505 xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1506 }
1507}
1508
1509static void xs_write_space(struct sock *sk)
1510{
1511 struct sock_xprt *transport;
1512 struct rpc_xprt *xprt;
1513
1514 if (!sk->sk_socket)
1515 return;
1516 clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1517
1518 if (unlikely(!(xprt = xprt_from_sock(sk))))
1519 return;
1520 transport = container_of(xprt, struct sock_xprt, xprt);
1521 if (!test_and_clear_bit(XPRT_SOCK_NOSPACE, &transport->sock_state))
1522 return;
1523 xs_run_error_worker(transport, XPRT_SOCK_WAKE_WRITE);
1524 sk->sk_write_pending--;
1525}
1526
1527/**
1528 * xs_udp_write_space - callback invoked when socket buffer space
1529 * becomes available
1530 * @sk: socket whose state has changed
1531 *
1532 * Called when more output buffer space is available for this socket.
1533 * We try not to wake our writers until they can make "significant"
1534 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1535 * with a bunch of small requests.
1536 */
1537static void xs_udp_write_space(struct sock *sk)
1538{
1539 /* from net/core/sock.c:sock_def_write_space */
1540 if (sock_writeable(sk))
1541 xs_write_space(sk);
1542}
1543
1544/**
1545 * xs_tcp_write_space - callback invoked when socket buffer space
1546 * becomes available
1547 * @sk: socket whose state has changed
1548 *
1549 * Called when more output buffer space is available for this socket.
1550 * We try not to wake our writers until they can make "significant"
1551 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1552 * with a bunch of small requests.
1553 */
1554static void xs_tcp_write_space(struct sock *sk)
1555{
1556 /* from net/core/stream.c:sk_stream_write_space */
1557 if (sk_stream_is_writeable(sk))
1558 xs_write_space(sk);
1559}
1560
1561static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1562{
1563 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1564 struct sock *sk = transport->inet;
1565
1566 if (transport->rcvsize) {
1567 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1568 sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1569 }
1570 if (transport->sndsize) {
1571 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1572 sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1573 sk->sk_write_space(sk);
1574 }
1575}
1576
1577/**
1578 * xs_udp_set_buffer_size - set send and receive limits
1579 * @xprt: generic transport
1580 * @sndsize: requested size of send buffer, in bytes
1581 * @rcvsize: requested size of receive buffer, in bytes
1582 *
1583 * Set socket send and receive buffer size limits.
1584 */
1585static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1586{
1587 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1588
1589 transport->sndsize = 0;
1590 if (sndsize)
1591 transport->sndsize = sndsize + 1024;
1592 transport->rcvsize = 0;
1593 if (rcvsize)
1594 transport->rcvsize = rcvsize + 1024;
1595
1596 xs_udp_do_set_buffer_size(xprt);
1597}
1598
1599/**
1600 * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1601 * @xprt: controlling transport
1602 * @task: task that timed out
1603 *
1604 * Adjust the congestion window after a retransmit timeout has occurred.
1605 */
1606static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1607{
1608 spin_lock(&xprt->transport_lock);
1609 xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1610 spin_unlock(&xprt->transport_lock);
1611}
1612
1613static int xs_get_random_port(void)
1614{
1615 unsigned short min = xprt_min_resvport, max = xprt_max_resvport;
1616 unsigned short range;
1617 unsigned short rand;
1618
1619 if (max < min)
1620 return -EADDRINUSE;
1621 range = max - min + 1;
1622 rand = get_random_u32_below(range);
1623 return rand + min;
1624}
1625
1626static unsigned short xs_sock_getport(struct socket *sock)
1627{
1628 struct sockaddr_storage buf;
1629 unsigned short port = 0;
1630
1631 if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0)
1632 goto out;
1633 switch (buf.ss_family) {
1634 case AF_INET6:
1635 port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1636 break;
1637 case AF_INET:
1638 port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1639 }
1640out:
1641 return port;
1642}
1643
1644/**
1645 * xs_set_port - reset the port number in the remote endpoint address
1646 * @xprt: generic transport
1647 * @port: new port number
1648 *
1649 */
1650static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1651{
1652 dprintk("RPC: setting port for xprt %p to %u\n", xprt, port);
1653
1654 rpc_set_port(xs_addr(xprt), port);
1655 xs_update_peer_port(xprt);
1656}
1657
1658static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1659{
1660 if (transport->srcport == 0 && transport->xprt.reuseport)
1661 transport->srcport = xs_sock_getport(sock);
1662}
1663
1664static int xs_get_srcport(struct sock_xprt *transport)
1665{
1666 int port = transport->srcport;
1667
1668 if (port == 0 && transport->xprt.resvport)
1669 port = xs_get_random_port();
1670 return port;
1671}
1672
1673static unsigned short xs_sock_srcport(struct rpc_xprt *xprt)
1674{
1675 struct sock_xprt *sock = container_of(xprt, struct sock_xprt, xprt);
1676 unsigned short ret = 0;
1677 mutex_lock(&sock->recv_mutex);
1678 if (sock->sock)
1679 ret = xs_sock_getport(sock->sock);
1680 mutex_unlock(&sock->recv_mutex);
1681 return ret;
1682}
1683
1684static int xs_sock_srcaddr(struct rpc_xprt *xprt, char *buf, size_t buflen)
1685{
1686 struct sock_xprt *sock = container_of(xprt, struct sock_xprt, xprt);
1687 union {
1688 struct sockaddr sa;
1689 struct sockaddr_storage st;
1690 } saddr;
1691 int ret = -ENOTCONN;
1692
1693 mutex_lock(&sock->recv_mutex);
1694 if (sock->sock) {
1695 ret = kernel_getsockname(sock->sock, &saddr.sa);
1696 if (ret >= 0)
1697 ret = snprintf(buf, buflen, "%pISc", &saddr.sa);
1698 }
1699 mutex_unlock(&sock->recv_mutex);
1700 return ret;
1701}
1702
1703static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1704{
1705 if (transport->srcport != 0)
1706 transport->srcport = 0;
1707 if (!transport->xprt.resvport)
1708 return 0;
1709 if (port <= xprt_min_resvport || port > xprt_max_resvport)
1710 return xprt_max_resvport;
1711 return --port;
1712}
1713static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1714{
1715 struct sockaddr_storage myaddr;
1716 int err, nloop = 0;
1717 int port = xs_get_srcport(transport);
1718 unsigned short last;
1719
1720 /*
1721 * If we are asking for any ephemeral port (i.e. port == 0 &&
1722 * transport->xprt.resvport == 0), don't bind. Let the local
1723 * port selection happen implicitly when the socket is used
1724 * (for example at connect time).
1725 *
1726 * This ensures that we can continue to establish TCP
1727 * connections even when all local ephemeral ports are already
1728 * a part of some TCP connection. This makes no difference
1729 * for UDP sockets, but also doesn't harm them.
1730 *
1731 * If we're asking for any reserved port (i.e. port == 0 &&
1732 * transport->xprt.resvport == 1) xs_get_srcport above will
1733 * ensure that port is non-zero and we will bind as needed.
1734 */
1735 if (port <= 0)
1736 return port;
1737
1738 memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1739 do {
1740 rpc_set_port((struct sockaddr *)&myaddr, port);
1741 err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1742 transport->xprt.addrlen);
1743 if (err == 0) {
1744 if (transport->xprt.reuseport)
1745 transport->srcport = port;
1746 break;
1747 }
1748 last = port;
1749 port = xs_next_srcport(transport, port);
1750 if (port > last)
1751 nloop++;
1752 } while (err == -EADDRINUSE && nloop != 2);
1753
1754 if (myaddr.ss_family == AF_INET)
1755 dprintk("RPC: %s %pI4:%u: %s (%d)\n", __func__,
1756 &((struct sockaddr_in *)&myaddr)->sin_addr,
1757 port, err ? "failed" : "ok", err);
1758 else
1759 dprintk("RPC: %s %pI6:%u: %s (%d)\n", __func__,
1760 &((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1761 port, err ? "failed" : "ok", err);
1762 return err;
1763}
1764
1765/*
1766 * We don't support autobind on AF_LOCAL sockets
1767 */
1768static void xs_local_rpcbind(struct rpc_task *task)
1769{
1770 xprt_set_bound(task->tk_xprt);
1771}
1772
1773static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1774{
1775}
1776
1777#ifdef CONFIG_DEBUG_LOCK_ALLOC
1778static struct lock_class_key xs_key[3];
1779static struct lock_class_key xs_slock_key[3];
1780
1781static inline void xs_reclassify_socketu(struct socket *sock)
1782{
1783 struct sock *sk = sock->sk;
1784
1785 sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1786 &xs_slock_key[0], "sk_lock-AF_LOCAL-RPC", &xs_key[0]);
1787}
1788
1789static inline void xs_reclassify_socket4(struct socket *sock)
1790{
1791 struct sock *sk = sock->sk;
1792
1793 sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1794 &xs_slock_key[1], "sk_lock-AF_INET-RPC", &xs_key[1]);
1795}
1796
1797static inline void xs_reclassify_socket6(struct socket *sock)
1798{
1799 struct sock *sk = sock->sk;
1800
1801 sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1802 &xs_slock_key[2], "sk_lock-AF_INET6-RPC", &xs_key[2]);
1803}
1804
1805static inline void xs_reclassify_socket(int family, struct socket *sock)
1806{
1807 if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
1808 return;
1809
1810 switch (family) {
1811 case AF_LOCAL:
1812 xs_reclassify_socketu(sock);
1813 break;
1814 case AF_INET:
1815 xs_reclassify_socket4(sock);
1816 break;
1817 case AF_INET6:
1818 xs_reclassify_socket6(sock);
1819 break;
1820 }
1821}
1822#else
1823static inline void xs_reclassify_socket(int family, struct socket *sock)
1824{
1825}
1826#endif
1827
1828static void xs_dummy_setup_socket(struct work_struct *work)
1829{
1830}
1831
1832static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1833 struct sock_xprt *transport, int family, int type,
1834 int protocol, bool reuseport)
1835{
1836 struct file *filp;
1837 struct socket *sock;
1838 int err;
1839
1840 err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1841 if (err < 0) {
1842 dprintk("RPC: can't create %d transport socket (%d).\n",
1843 protocol, -err);
1844 goto out;
1845 }
1846 xs_reclassify_socket(family, sock);
1847
1848 if (reuseport)
1849 sock_set_reuseport(sock->sk);
1850
1851 err = xs_bind(transport, sock);
1852 if (err) {
1853 sock_release(sock);
1854 goto out;
1855 }
1856
1857 filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1858 if (IS_ERR(filp))
1859 return ERR_CAST(filp);
1860 transport->file = filp;
1861
1862 return sock;
1863out:
1864 return ERR_PTR(err);
1865}
1866
1867static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1868 struct socket *sock)
1869{
1870 struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1871 xprt);
1872
1873 if (!transport->inet) {
1874 struct sock *sk = sock->sk;
1875
1876 lock_sock(sk);
1877
1878 xs_save_old_callbacks(transport, sk);
1879
1880 sk->sk_user_data = xprt;
1881 sk->sk_data_ready = xs_data_ready;
1882 sk->sk_write_space = xs_udp_write_space;
1883 sk->sk_state_change = xs_local_state_change;
1884 sk->sk_error_report = xs_error_report;
1885 sk->sk_use_task_frag = false;
1886
1887 xprt_clear_connected(xprt);
1888
1889 /* Reset to new socket */
1890 transport->sock = sock;
1891 transport->inet = sk;
1892
1893 release_sock(sk);
1894 }
1895
1896 xs_stream_start_connect(transport);
1897
1898 return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1899}
1900
1901/**
1902 * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1903 * @transport: socket transport to connect
1904 */
1905static int xs_local_setup_socket(struct sock_xprt *transport)
1906{
1907 struct rpc_xprt *xprt = &transport->xprt;
1908 struct file *filp;
1909 struct socket *sock;
1910 int status;
1911
1912 status = __sock_create(xprt->xprt_net, AF_LOCAL,
1913 SOCK_STREAM, 0, &sock, 1);
1914 if (status < 0) {
1915 dprintk("RPC: can't create AF_LOCAL "
1916 "transport socket (%d).\n", -status);
1917 goto out;
1918 }
1919 xs_reclassify_socket(AF_LOCAL, sock);
1920
1921 filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1922 if (IS_ERR(filp)) {
1923 status = PTR_ERR(filp);
1924 goto out;
1925 }
1926 transport->file = filp;
1927
1928 dprintk("RPC: worker connecting xprt %p via AF_LOCAL to %s\n",
1929 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1930
1931 status = xs_local_finish_connecting(xprt, sock);
1932 trace_rpc_socket_connect(xprt, sock, status);
1933 switch (status) {
1934 case 0:
1935 dprintk("RPC: xprt %p connected to %s\n",
1936 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1937 xprt->stat.connect_count++;
1938 xprt->stat.connect_time += (long)jiffies -
1939 xprt->stat.connect_start;
1940 xprt_set_connected(xprt);
1941 break;
1942 case -ENOBUFS:
1943 break;
1944 case -ENOENT:
1945 dprintk("RPC: xprt %p: socket %s does not exist\n",
1946 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1947 break;
1948 case -ECONNREFUSED:
1949 dprintk("RPC: xprt %p: connection refused for %s\n",
1950 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1951 break;
1952 default:
1953 printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
1954 __func__, -status,
1955 xprt->address_strings[RPC_DISPLAY_ADDR]);
1956 }
1957
1958out:
1959 xprt_clear_connecting(xprt);
1960 xprt_wake_pending_tasks(xprt, status);
1961 return status;
1962}
1963
1964static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
1965{
1966 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1967 int ret;
1968
1969 if (transport->file)
1970 goto force_disconnect;
1971
1972 if (RPC_IS_ASYNC(task)) {
1973 /*
1974 * We want the AF_LOCAL connect to be resolved in the
1975 * filesystem namespace of the process making the rpc
1976 * call. Thus we connect synchronously.
1977 *
1978 * If we want to support asynchronous AF_LOCAL calls,
1979 * we'll need to figure out how to pass a namespace to
1980 * connect.
1981 */
1982 rpc_task_set_rpc_status(task, -ENOTCONN);
1983 goto out_wake;
1984 }
1985 ret = xs_local_setup_socket(transport);
1986 if (ret && !RPC_IS_SOFTCONN(task))
1987 msleep_interruptible(15000);
1988 return;
1989force_disconnect:
1990 xprt_force_disconnect(xprt);
1991out_wake:
1992 xprt_clear_connecting(xprt);
1993 xprt_wake_pending_tasks(xprt, -ENOTCONN);
1994}
1995
1996#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
1997/*
1998 * Note that this should be called with XPRT_LOCKED held, or recv_mutex
1999 * held, or when we otherwise know that we have exclusive access to the
2000 * socket, to guard against races with xs_reset_transport.
2001 */
2002static void xs_set_memalloc(struct rpc_xprt *xprt)
2003{
2004 struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
2005 xprt);
2006
2007 /*
2008 * If there's no sock, then we have nothing to set. The
2009 * reconnecting process will get it for us.
2010 */
2011 if (!transport->inet)
2012 return;
2013 if (atomic_read(&xprt->swapper))
2014 sk_set_memalloc(transport->inet);
2015}
2016
2017/**
2018 * xs_enable_swap - Tag this transport as being used for swap.
2019 * @xprt: transport to tag
2020 *
2021 * Take a reference to this transport on behalf of the rpc_clnt, and
2022 * optionally mark it for swapping if it wasn't already.
2023 */
2024static int
2025xs_enable_swap(struct rpc_xprt *xprt)
2026{
2027 struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2028
2029 mutex_lock(&xs->recv_mutex);
2030 if (atomic_inc_return(&xprt->swapper) == 1 &&
2031 xs->inet)
2032 sk_set_memalloc(xs->inet);
2033 mutex_unlock(&xs->recv_mutex);
2034 return 0;
2035}
2036
2037/**
2038 * xs_disable_swap - Untag this transport as being used for swap.
2039 * @xprt: transport to tag
2040 *
2041 * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
2042 * swapper refcount goes to 0, untag the socket as a memalloc socket.
2043 */
2044static void
2045xs_disable_swap(struct rpc_xprt *xprt)
2046{
2047 struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2048
2049 mutex_lock(&xs->recv_mutex);
2050 if (atomic_dec_and_test(&xprt->swapper) &&
2051 xs->inet)
2052 sk_clear_memalloc(xs->inet);
2053 mutex_unlock(&xs->recv_mutex);
2054}
2055#else
2056static void xs_set_memalloc(struct rpc_xprt *xprt)
2057{
2058}
2059
2060static int
2061xs_enable_swap(struct rpc_xprt *xprt)
2062{
2063 return -EINVAL;
2064}
2065
2066static void
2067xs_disable_swap(struct rpc_xprt *xprt)
2068{
2069}
2070#endif
2071
2072static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2073{
2074 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2075
2076 if (!transport->inet) {
2077 struct sock *sk = sock->sk;
2078
2079 lock_sock(sk);
2080
2081 xs_save_old_callbacks(transport, sk);
2082
2083 sk->sk_user_data = xprt;
2084 sk->sk_data_ready = xs_data_ready;
2085 sk->sk_write_space = xs_udp_write_space;
2086 sk->sk_use_task_frag = false;
2087
2088 xprt_set_connected(xprt);
2089
2090 /* Reset to new socket */
2091 transport->sock = sock;
2092 transport->inet = sk;
2093
2094 xs_set_memalloc(xprt);
2095
2096 release_sock(sk);
2097 }
2098 xs_udp_do_set_buffer_size(xprt);
2099
2100 xprt->stat.connect_start = jiffies;
2101}
2102
2103static void xs_udp_setup_socket(struct work_struct *work)
2104{
2105 struct sock_xprt *transport =
2106 container_of(work, struct sock_xprt, connect_worker.work);
2107 struct rpc_xprt *xprt = &transport->xprt;
2108 struct socket *sock;
2109 int status = -EIO;
2110 unsigned int pflags = current->flags;
2111
2112 if (atomic_read(&xprt->swapper))
2113 current->flags |= PF_MEMALLOC;
2114 sock = xs_create_sock(xprt, transport,
2115 xs_addr(xprt)->sa_family, SOCK_DGRAM,
2116 IPPROTO_UDP, false);
2117 if (IS_ERR(sock))
2118 goto out;
2119
2120 dprintk("RPC: worker connecting xprt %p via %s to "
2121 "%s (port %s)\n", xprt,
2122 xprt->address_strings[RPC_DISPLAY_PROTO],
2123 xprt->address_strings[RPC_DISPLAY_ADDR],
2124 xprt->address_strings[RPC_DISPLAY_PORT]);
2125
2126 xs_udp_finish_connecting(xprt, sock);
2127 trace_rpc_socket_connect(xprt, sock, 0);
2128 status = 0;
2129out:
2130 xprt_clear_connecting(xprt);
2131 xprt_unlock_connect(xprt, transport);
2132 xprt_wake_pending_tasks(xprt, status);
2133 current_restore_flags(pflags, PF_MEMALLOC);
2134}
2135
2136/**
2137 * xs_tcp_shutdown - gracefully shut down a TCP socket
2138 * @xprt: transport
2139 *
2140 * Initiates a graceful shutdown of the TCP socket by calling the
2141 * equivalent of shutdown(SHUT_RDWR);
2142 */
2143static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2144{
2145 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2146 struct socket *sock = transport->sock;
2147 int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
2148
2149 if (sock == NULL)
2150 return;
2151 if (!xprt->reuseport) {
2152 xs_close(xprt);
2153 return;
2154 }
2155 switch (skst) {
2156 case TCP_FIN_WAIT1:
2157 case TCP_FIN_WAIT2:
2158 break;
2159 case TCP_ESTABLISHED:
2160 case TCP_CLOSE_WAIT:
2161 kernel_sock_shutdown(sock, SHUT_RDWR);
2162 trace_rpc_socket_shutdown(xprt, sock);
2163 break;
2164 default:
2165 xs_reset_transport(transport);
2166 }
2167}
2168
2169static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
2170 struct socket *sock)
2171{
2172 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2173 unsigned int keepidle;
2174 unsigned int keepcnt;
2175 unsigned int timeo;
2176
2177 spin_lock(&xprt->transport_lock);
2178 keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
2179 keepcnt = xprt->timeout->to_retries + 1;
2180 timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2181 (xprt->timeout->to_retries + 1);
2182 clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2183 spin_unlock(&xprt->transport_lock);
2184
2185 /* TCP Keepalive options */
2186 sock_set_keepalive(sock->sk);
2187 tcp_sock_set_keepidle(sock->sk, keepidle);
2188 tcp_sock_set_keepintvl(sock->sk, keepidle);
2189 tcp_sock_set_keepcnt(sock->sk, keepcnt);
2190
2191 /* TCP user timeout (see RFC5482) */
2192 tcp_sock_set_user_timeout(sock->sk, timeo);
2193}
2194
2195static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
2196 unsigned long connect_timeout,
2197 unsigned long reconnect_timeout)
2198{
2199 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2200 struct rpc_timeout to;
2201 unsigned long initval;
2202
2203 spin_lock(&xprt->transport_lock);
2204 if (reconnect_timeout < xprt->max_reconnect_timeout)
2205 xprt->max_reconnect_timeout = reconnect_timeout;
2206 if (connect_timeout < xprt->connect_timeout) {
2207 memcpy(&to, xprt->timeout, sizeof(to));
2208 initval = DIV_ROUND_UP(connect_timeout, to.to_retries + 1);
2209 /* Arbitrary lower limit */
2210 if (initval < XS_TCP_INIT_REEST_TO << 1)
2211 initval = XS_TCP_INIT_REEST_TO << 1;
2212 to.to_initval = initval;
2213 to.to_maxval = initval;
2214 memcpy(&transport->tcp_timeout, &to,
2215 sizeof(transport->tcp_timeout));
2216 xprt->timeout = &transport->tcp_timeout;
2217 xprt->connect_timeout = connect_timeout;
2218 }
2219 set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2220 spin_unlock(&xprt->transport_lock);
2221}
2222
2223static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2224{
2225 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2226
2227 if (!transport->inet) {
2228 struct sock *sk = sock->sk;
2229
2230 /* Avoid temporary address, they are bad for long-lived
2231 * connections such as NFS mounts.
2232 * RFC4941, section 3.6 suggests that:
2233 * Individual applications, which have specific
2234 * knowledge about the normal duration of connections,
2235 * MAY override this as appropriate.
2236 */
2237 if (xs_addr(xprt)->sa_family == PF_INET6) {
2238 ip6_sock_set_addr_preferences(sk,
2239 IPV6_PREFER_SRC_PUBLIC);
2240 }
2241
2242 xs_tcp_set_socket_timeouts(xprt, sock);
2243 tcp_sock_set_nodelay(sk);
2244
2245 lock_sock(sk);
2246
2247 xs_save_old_callbacks(transport, sk);
2248
2249 sk->sk_user_data = xprt;
2250 sk->sk_data_ready = xs_data_ready;
2251 sk->sk_state_change = xs_tcp_state_change;
2252 sk->sk_write_space = xs_tcp_write_space;
2253 sk->sk_error_report = xs_error_report;
2254 sk->sk_use_task_frag = false;
2255
2256 /* socket options */
2257 sock_reset_flag(sk, SOCK_LINGER);
2258
2259 xprt_clear_connected(xprt);
2260
2261 /* Reset to new socket */
2262 transport->sock = sock;
2263 transport->inet = sk;
2264
2265 release_sock(sk);
2266 }
2267
2268 if (!xprt_bound(xprt))
2269 return -ENOTCONN;
2270
2271 xs_set_memalloc(xprt);
2272
2273 xs_stream_start_connect(transport);
2274
2275 /* Tell the socket layer to start connecting... */
2276 set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2277 return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2278}
2279
2280/**
2281 * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2282 * @work: queued work item
2283 *
2284 * Invoked by a work queue tasklet.
2285 */
2286static void xs_tcp_setup_socket(struct work_struct *work)
2287{
2288 struct sock_xprt *transport =
2289 container_of(work, struct sock_xprt, connect_worker.work);
2290 struct socket *sock = transport->sock;
2291 struct rpc_xprt *xprt = &transport->xprt;
2292 int status;
2293 unsigned int pflags = current->flags;
2294
2295 if (atomic_read(&xprt->swapper))
2296 current->flags |= PF_MEMALLOC;
2297
2298 if (xprt_connected(xprt))
2299 goto out;
2300 if (test_and_clear_bit(XPRT_SOCK_CONNECT_SENT,
2301 &transport->sock_state) ||
2302 !sock) {
2303 xs_reset_transport(transport);
2304 sock = xs_create_sock(xprt, transport, xs_addr(xprt)->sa_family,
2305 SOCK_STREAM, IPPROTO_TCP, true);
2306 if (IS_ERR(sock)) {
2307 xprt_wake_pending_tasks(xprt, PTR_ERR(sock));
2308 goto out;
2309 }
2310 }
2311
2312 dprintk("RPC: worker connecting xprt %p via %s to "
2313 "%s (port %s)\n", xprt,
2314 xprt->address_strings[RPC_DISPLAY_PROTO],
2315 xprt->address_strings[RPC_DISPLAY_ADDR],
2316 xprt->address_strings[RPC_DISPLAY_PORT]);
2317
2318 status = xs_tcp_finish_connecting(xprt, sock);
2319 trace_rpc_socket_connect(xprt, sock, status);
2320 dprintk("RPC: %p connect status %d connected %d sock state %d\n",
2321 xprt, -status, xprt_connected(xprt),
2322 sock->sk->sk_state);
2323 switch (status) {
2324 case 0:
2325 case -EINPROGRESS:
2326 /* SYN_SENT! */
2327 set_bit(XPRT_SOCK_CONNECT_SENT, &transport->sock_state);
2328 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2329 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2330 fallthrough;
2331 case -EALREADY:
2332 goto out_unlock;
2333 case -EADDRNOTAVAIL:
2334 /* Source port number is unavailable. Try a new one! */
2335 transport->srcport = 0;
2336 status = -EAGAIN;
2337 break;
2338 case -EINVAL:
2339 /* Happens, for instance, if the user specified a link
2340 * local IPv6 address without a scope-id.
2341 */
2342 case -ECONNREFUSED:
2343 case -ECONNRESET:
2344 case -ENETDOWN:
2345 case -ENETUNREACH:
2346 case -EHOSTUNREACH:
2347 case -EADDRINUSE:
2348 case -ENOBUFS:
2349 break;
2350 default:
2351 printk("%s: connect returned unhandled error %d\n",
2352 __func__, status);
2353 status = -EAGAIN;
2354 }
2355
2356 /* xs_tcp_force_close() wakes tasks with a fixed error code.
2357 * We need to wake them first to ensure the correct error code.
2358 */
2359 xprt_wake_pending_tasks(xprt, status);
2360 xs_tcp_force_close(xprt);
2361out:
2362 xprt_clear_connecting(xprt);
2363out_unlock:
2364 xprt_unlock_connect(xprt, transport);
2365 current_restore_flags(pflags, PF_MEMALLOC);
2366}
2367
2368/**
2369 * xs_connect - connect a socket to a remote endpoint
2370 * @xprt: pointer to transport structure
2371 * @task: address of RPC task that manages state of connect request
2372 *
2373 * TCP: If the remote end dropped the connection, delay reconnecting.
2374 *
2375 * UDP socket connects are synchronous, but we use a work queue anyway
2376 * to guarantee that even unprivileged user processes can set up a
2377 * socket on a privileged port.
2378 *
2379 * If a UDP socket connect fails, the delay behavior here prevents
2380 * retry floods (hard mounts).
2381 */
2382static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2383{
2384 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2385 unsigned long delay = 0;
2386
2387 WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2388
2389 if (transport->sock != NULL) {
2390 dprintk("RPC: xs_connect delayed xprt %p for %lu "
2391 "seconds\n", xprt, xprt->reestablish_timeout / HZ);
2392
2393 delay = xprt_reconnect_delay(xprt);
2394 xprt_reconnect_backoff(xprt, XS_TCP_INIT_REEST_TO);
2395
2396 } else
2397 dprintk("RPC: xs_connect scheduled xprt %p\n", xprt);
2398
2399 queue_delayed_work(xprtiod_workqueue,
2400 &transport->connect_worker,
2401 delay);
2402}
2403
2404static void xs_wake_disconnect(struct sock_xprt *transport)
2405{
2406 if (test_and_clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state))
2407 xs_tcp_force_close(&transport->xprt);
2408}
2409
2410static void xs_wake_write(struct sock_xprt *transport)
2411{
2412 if (test_and_clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state))
2413 xprt_write_space(&transport->xprt);
2414}
2415
2416static void xs_wake_error(struct sock_xprt *transport)
2417{
2418 int sockerr;
2419
2420 if (!test_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2421 return;
2422 mutex_lock(&transport->recv_mutex);
2423 if (transport->sock == NULL)
2424 goto out;
2425 if (!test_and_clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2426 goto out;
2427 sockerr = xchg(&transport->xprt_err, 0);
2428 if (sockerr < 0)
2429 xprt_wake_pending_tasks(&transport->xprt, sockerr);
2430out:
2431 mutex_unlock(&transport->recv_mutex);
2432}
2433
2434static void xs_wake_pending(struct sock_xprt *transport)
2435{
2436 if (test_and_clear_bit(XPRT_SOCK_WAKE_PENDING, &transport->sock_state))
2437 xprt_wake_pending_tasks(&transport->xprt, -EAGAIN);
2438}
2439
2440static void xs_error_handle(struct work_struct *work)
2441{
2442 struct sock_xprt *transport = container_of(work,
2443 struct sock_xprt, error_worker);
2444
2445 xs_wake_disconnect(transport);
2446 xs_wake_write(transport);
2447 xs_wake_error(transport);
2448 xs_wake_pending(transport);
2449}
2450
2451/**
2452 * xs_local_print_stats - display AF_LOCAL socket-specific stats
2453 * @xprt: rpc_xprt struct containing statistics
2454 * @seq: output file
2455 *
2456 */
2457static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2458{
2459 long idle_time = 0;
2460
2461 if (xprt_connected(xprt))
2462 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2463
2464 seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2465 "%llu %llu %lu %llu %llu\n",
2466 xprt->stat.bind_count,
2467 xprt->stat.connect_count,
2468 xprt->stat.connect_time / HZ,
2469 idle_time,
2470 xprt->stat.sends,
2471 xprt->stat.recvs,
2472 xprt->stat.bad_xids,
2473 xprt->stat.req_u,
2474 xprt->stat.bklog_u,
2475 xprt->stat.max_slots,
2476 xprt->stat.sending_u,
2477 xprt->stat.pending_u);
2478}
2479
2480/**
2481 * xs_udp_print_stats - display UDP socket-specific stats
2482 * @xprt: rpc_xprt struct containing statistics
2483 * @seq: output file
2484 *
2485 */
2486static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2487{
2488 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2489
2490 seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2491 "%lu %llu %llu\n",
2492 transport->srcport,
2493 xprt->stat.bind_count,
2494 xprt->stat.sends,
2495 xprt->stat.recvs,
2496 xprt->stat.bad_xids,
2497 xprt->stat.req_u,
2498 xprt->stat.bklog_u,
2499 xprt->stat.max_slots,
2500 xprt->stat.sending_u,
2501 xprt->stat.pending_u);
2502}
2503
2504/**
2505 * xs_tcp_print_stats - display TCP socket-specific stats
2506 * @xprt: rpc_xprt struct containing statistics
2507 * @seq: output file
2508 *
2509 */
2510static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2511{
2512 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2513 long idle_time = 0;
2514
2515 if (xprt_connected(xprt))
2516 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2517
2518 seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2519 "%llu %llu %lu %llu %llu\n",
2520 transport->srcport,
2521 xprt->stat.bind_count,
2522 xprt->stat.connect_count,
2523 xprt->stat.connect_time / HZ,
2524 idle_time,
2525 xprt->stat.sends,
2526 xprt->stat.recvs,
2527 xprt->stat.bad_xids,
2528 xprt->stat.req_u,
2529 xprt->stat.bklog_u,
2530 xprt->stat.max_slots,
2531 xprt->stat.sending_u,
2532 xprt->stat.pending_u);
2533}
2534
2535/*
2536 * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2537 * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2538 * to use the server side send routines.
2539 */
2540static int bc_malloc(struct rpc_task *task)
2541{
2542 struct rpc_rqst *rqst = task->tk_rqstp;
2543 size_t size = rqst->rq_callsize;
2544 struct page *page;
2545 struct rpc_buffer *buf;
2546
2547 if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2548 WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2549 size);
2550 return -EINVAL;
2551 }
2552
2553 page = alloc_page(GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
2554 if (!page)
2555 return -ENOMEM;
2556
2557 buf = page_address(page);
2558 buf->len = PAGE_SIZE;
2559
2560 rqst->rq_buffer = buf->data;
2561 rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2562 return 0;
2563}
2564
2565/*
2566 * Free the space allocated in the bc_alloc routine
2567 */
2568static void bc_free(struct rpc_task *task)
2569{
2570 void *buffer = task->tk_rqstp->rq_buffer;
2571 struct rpc_buffer *buf;
2572
2573 buf = container_of(buffer, struct rpc_buffer, data);
2574 free_page((unsigned long)buf);
2575}
2576
2577static int bc_sendto(struct rpc_rqst *req)
2578{
2579 struct xdr_buf *xdr = &req->rq_snd_buf;
2580 struct sock_xprt *transport =
2581 container_of(req->rq_xprt, struct sock_xprt, xprt);
2582 struct msghdr msg = {
2583 .msg_flags = 0,
2584 };
2585 rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT |
2586 (u32)xdr->len);
2587 unsigned int sent = 0;
2588 int err;
2589
2590 req->rq_xtime = ktime_get();
2591 err = xdr_alloc_bvec(xdr, rpc_task_gfp_mask());
2592 if (err < 0)
2593 return err;
2594 err = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, marker, &sent);
2595 xdr_free_bvec(xdr);
2596 if (err < 0 || sent != (xdr->len + sizeof(marker)))
2597 return -EAGAIN;
2598 return sent;
2599}
2600
2601/**
2602 * bc_send_request - Send a backchannel Call on a TCP socket
2603 * @req: rpc_rqst containing Call message to be sent
2604 *
2605 * xpt_mutex ensures @rqstp's whole message is written to the socket
2606 * without interruption.
2607 *
2608 * Return values:
2609 * %0 if the message was sent successfully
2610 * %ENOTCONN if the message was not sent
2611 */
2612static int bc_send_request(struct rpc_rqst *req)
2613{
2614 struct svc_xprt *xprt;
2615 int len;
2616
2617 /*
2618 * Get the server socket associated with this callback xprt
2619 */
2620 xprt = req->rq_xprt->bc_xprt;
2621
2622 /*
2623 * Grab the mutex to serialize data as the connection is shared
2624 * with the fore channel
2625 */
2626 mutex_lock(&xprt->xpt_mutex);
2627 if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2628 len = -ENOTCONN;
2629 else
2630 len = bc_sendto(req);
2631 mutex_unlock(&xprt->xpt_mutex);
2632
2633 if (len > 0)
2634 len = 0;
2635
2636 return len;
2637}
2638
2639/*
2640 * The close routine. Since this is client initiated, we do nothing
2641 */
2642
2643static void bc_close(struct rpc_xprt *xprt)
2644{
2645 xprt_disconnect_done(xprt);
2646}
2647
2648/*
2649 * The xprt destroy routine. Again, because this connection is client
2650 * initiated, we do nothing
2651 */
2652
2653static void bc_destroy(struct rpc_xprt *xprt)
2654{
2655 dprintk("RPC: bc_destroy xprt %p\n", xprt);
2656
2657 xs_xprt_free(xprt);
2658 module_put(THIS_MODULE);
2659}
2660
2661static const struct rpc_xprt_ops xs_local_ops = {
2662 .reserve_xprt = xprt_reserve_xprt,
2663 .release_xprt = xprt_release_xprt,
2664 .alloc_slot = xprt_alloc_slot,
2665 .free_slot = xprt_free_slot,
2666 .rpcbind = xs_local_rpcbind,
2667 .set_port = xs_local_set_port,
2668 .connect = xs_local_connect,
2669 .buf_alloc = rpc_malloc,
2670 .buf_free = rpc_free,
2671 .prepare_request = xs_stream_prepare_request,
2672 .send_request = xs_local_send_request,
2673 .wait_for_reply_request = xprt_wait_for_reply_request_def,
2674 .close = xs_close,
2675 .destroy = xs_destroy,
2676 .print_stats = xs_local_print_stats,
2677 .enable_swap = xs_enable_swap,
2678 .disable_swap = xs_disable_swap,
2679};
2680
2681static const struct rpc_xprt_ops xs_udp_ops = {
2682 .set_buffer_size = xs_udp_set_buffer_size,
2683 .reserve_xprt = xprt_reserve_xprt_cong,
2684 .release_xprt = xprt_release_xprt_cong,
2685 .alloc_slot = xprt_alloc_slot,
2686 .free_slot = xprt_free_slot,
2687 .rpcbind = rpcb_getport_async,
2688 .set_port = xs_set_port,
2689 .connect = xs_connect,
2690 .get_srcaddr = xs_sock_srcaddr,
2691 .get_srcport = xs_sock_srcport,
2692 .buf_alloc = rpc_malloc,
2693 .buf_free = rpc_free,
2694 .send_request = xs_udp_send_request,
2695 .wait_for_reply_request = xprt_wait_for_reply_request_rtt,
2696 .timer = xs_udp_timer,
2697 .release_request = xprt_release_rqst_cong,
2698 .close = xs_close,
2699 .destroy = xs_destroy,
2700 .print_stats = xs_udp_print_stats,
2701 .enable_swap = xs_enable_swap,
2702 .disable_swap = xs_disable_swap,
2703 .inject_disconnect = xs_inject_disconnect,
2704};
2705
2706static const struct rpc_xprt_ops xs_tcp_ops = {
2707 .reserve_xprt = xprt_reserve_xprt,
2708 .release_xprt = xprt_release_xprt,
2709 .alloc_slot = xprt_alloc_slot,
2710 .free_slot = xprt_free_slot,
2711 .rpcbind = rpcb_getport_async,
2712 .set_port = xs_set_port,
2713 .connect = xs_connect,
2714 .get_srcaddr = xs_sock_srcaddr,
2715 .get_srcport = xs_sock_srcport,
2716 .buf_alloc = rpc_malloc,
2717 .buf_free = rpc_free,
2718 .prepare_request = xs_stream_prepare_request,
2719 .send_request = xs_tcp_send_request,
2720 .wait_for_reply_request = xprt_wait_for_reply_request_def,
2721 .close = xs_tcp_shutdown,
2722 .destroy = xs_destroy,
2723 .set_connect_timeout = xs_tcp_set_connect_timeout,
2724 .print_stats = xs_tcp_print_stats,
2725 .enable_swap = xs_enable_swap,
2726 .disable_swap = xs_disable_swap,
2727 .inject_disconnect = xs_inject_disconnect,
2728#ifdef CONFIG_SUNRPC_BACKCHANNEL
2729 .bc_setup = xprt_setup_bc,
2730 .bc_maxpayload = xs_tcp_bc_maxpayload,
2731 .bc_num_slots = xprt_bc_max_slots,
2732 .bc_free_rqst = xprt_free_bc_rqst,
2733 .bc_destroy = xprt_destroy_bc,
2734#endif
2735};
2736
2737/*
2738 * The rpc_xprt_ops for the server backchannel
2739 */
2740
2741static const struct rpc_xprt_ops bc_tcp_ops = {
2742 .reserve_xprt = xprt_reserve_xprt,
2743 .release_xprt = xprt_release_xprt,
2744 .alloc_slot = xprt_alloc_slot,
2745 .free_slot = xprt_free_slot,
2746 .buf_alloc = bc_malloc,
2747 .buf_free = bc_free,
2748 .send_request = bc_send_request,
2749 .wait_for_reply_request = xprt_wait_for_reply_request_def,
2750 .close = bc_close,
2751 .destroy = bc_destroy,
2752 .print_stats = xs_tcp_print_stats,
2753 .enable_swap = xs_enable_swap,
2754 .disable_swap = xs_disable_swap,
2755 .inject_disconnect = xs_inject_disconnect,
2756};
2757
2758static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2759{
2760 static const struct sockaddr_in sin = {
2761 .sin_family = AF_INET,
2762 .sin_addr.s_addr = htonl(INADDR_ANY),
2763 };
2764 static const struct sockaddr_in6 sin6 = {
2765 .sin6_family = AF_INET6,
2766 .sin6_addr = IN6ADDR_ANY_INIT,
2767 };
2768
2769 switch (family) {
2770 case AF_LOCAL:
2771 break;
2772 case AF_INET:
2773 memcpy(sap, &sin, sizeof(sin));
2774 break;
2775 case AF_INET6:
2776 memcpy(sap, &sin6, sizeof(sin6));
2777 break;
2778 default:
2779 dprintk("RPC: %s: Bad address family\n", __func__);
2780 return -EAFNOSUPPORT;
2781 }
2782 return 0;
2783}
2784
2785static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2786 unsigned int slot_table_size,
2787 unsigned int max_slot_table_size)
2788{
2789 struct rpc_xprt *xprt;
2790 struct sock_xprt *new;
2791
2792 if (args->addrlen > sizeof(xprt->addr)) {
2793 dprintk("RPC: xs_setup_xprt: address too large\n");
2794 return ERR_PTR(-EBADF);
2795 }
2796
2797 xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2798 max_slot_table_size);
2799 if (xprt == NULL) {
2800 dprintk("RPC: xs_setup_xprt: couldn't allocate "
2801 "rpc_xprt\n");
2802 return ERR_PTR(-ENOMEM);
2803 }
2804
2805 new = container_of(xprt, struct sock_xprt, xprt);
2806 mutex_init(&new->recv_mutex);
2807 memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2808 xprt->addrlen = args->addrlen;
2809 if (args->srcaddr)
2810 memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2811 else {
2812 int err;
2813 err = xs_init_anyaddr(args->dstaddr->sa_family,
2814 (struct sockaddr *)&new->srcaddr);
2815 if (err != 0) {
2816 xprt_free(xprt);
2817 return ERR_PTR(err);
2818 }
2819 }
2820
2821 return xprt;
2822}
2823
2824static const struct rpc_timeout xs_local_default_timeout = {
2825 .to_initval = 10 * HZ,
2826 .to_maxval = 10 * HZ,
2827 .to_retries = 2,
2828};
2829
2830/**
2831 * xs_setup_local - Set up transport to use an AF_LOCAL socket
2832 * @args: rpc transport creation arguments
2833 *
2834 * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2835 */
2836static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2837{
2838 struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2839 struct sock_xprt *transport;
2840 struct rpc_xprt *xprt;
2841 struct rpc_xprt *ret;
2842
2843 xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2844 xprt_max_tcp_slot_table_entries);
2845 if (IS_ERR(xprt))
2846 return xprt;
2847 transport = container_of(xprt, struct sock_xprt, xprt);
2848
2849 xprt->prot = 0;
2850 xprt->xprt_class = &xs_local_transport;
2851 xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2852
2853 xprt->bind_timeout = XS_BIND_TO;
2854 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2855 xprt->idle_timeout = XS_IDLE_DISC_TO;
2856
2857 xprt->ops = &xs_local_ops;
2858 xprt->timeout = &xs_local_default_timeout;
2859
2860 INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2861 INIT_WORK(&transport->error_worker, xs_error_handle);
2862 INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket);
2863
2864 switch (sun->sun_family) {
2865 case AF_LOCAL:
2866 if (sun->sun_path[0] != '/') {
2867 dprintk("RPC: bad AF_LOCAL address: %s\n",
2868 sun->sun_path);
2869 ret = ERR_PTR(-EINVAL);
2870 goto out_err;
2871 }
2872 xprt_set_bound(xprt);
2873 xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
2874 break;
2875 default:
2876 ret = ERR_PTR(-EAFNOSUPPORT);
2877 goto out_err;
2878 }
2879
2880 dprintk("RPC: set up xprt to %s via AF_LOCAL\n",
2881 xprt->address_strings[RPC_DISPLAY_ADDR]);
2882
2883 if (try_module_get(THIS_MODULE))
2884 return xprt;
2885 ret = ERR_PTR(-EINVAL);
2886out_err:
2887 xs_xprt_free(xprt);
2888 return ret;
2889}
2890
2891static const struct rpc_timeout xs_udp_default_timeout = {
2892 .to_initval = 5 * HZ,
2893 .to_maxval = 30 * HZ,
2894 .to_increment = 5 * HZ,
2895 .to_retries = 5,
2896};
2897
2898/**
2899 * xs_setup_udp - Set up transport to use a UDP socket
2900 * @args: rpc transport creation arguments
2901 *
2902 */
2903static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2904{
2905 struct sockaddr *addr = args->dstaddr;
2906 struct rpc_xprt *xprt;
2907 struct sock_xprt *transport;
2908 struct rpc_xprt *ret;
2909
2910 xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2911 xprt_udp_slot_table_entries);
2912 if (IS_ERR(xprt))
2913 return xprt;
2914 transport = container_of(xprt, struct sock_xprt, xprt);
2915
2916 xprt->prot = IPPROTO_UDP;
2917 xprt->xprt_class = &xs_udp_transport;
2918 /* XXX: header size can vary due to auth type, IPv6, etc. */
2919 xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2920
2921 xprt->bind_timeout = XS_BIND_TO;
2922 xprt->reestablish_timeout = XS_UDP_REEST_TO;
2923 xprt->idle_timeout = XS_IDLE_DISC_TO;
2924
2925 xprt->ops = &xs_udp_ops;
2926
2927 xprt->timeout = &xs_udp_default_timeout;
2928
2929 INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
2930 INIT_WORK(&transport->error_worker, xs_error_handle);
2931 INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
2932
2933 switch (addr->sa_family) {
2934 case AF_INET:
2935 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2936 xprt_set_bound(xprt);
2937
2938 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2939 break;
2940 case AF_INET6:
2941 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2942 xprt_set_bound(xprt);
2943
2944 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2945 break;
2946 default:
2947 ret = ERR_PTR(-EAFNOSUPPORT);
2948 goto out_err;
2949 }
2950
2951 if (xprt_bound(xprt))
2952 dprintk("RPC: set up xprt to %s (port %s) via %s\n",
2953 xprt->address_strings[RPC_DISPLAY_ADDR],
2954 xprt->address_strings[RPC_DISPLAY_PORT],
2955 xprt->address_strings[RPC_DISPLAY_PROTO]);
2956 else
2957 dprintk("RPC: set up xprt to %s (autobind) via %s\n",
2958 xprt->address_strings[RPC_DISPLAY_ADDR],
2959 xprt->address_strings[RPC_DISPLAY_PROTO]);
2960
2961 if (try_module_get(THIS_MODULE))
2962 return xprt;
2963 ret = ERR_PTR(-EINVAL);
2964out_err:
2965 xs_xprt_free(xprt);
2966 return ret;
2967}
2968
2969static const struct rpc_timeout xs_tcp_default_timeout = {
2970 .to_initval = 60 * HZ,
2971 .to_maxval = 60 * HZ,
2972 .to_retries = 2,
2973};
2974
2975/**
2976 * xs_setup_tcp - Set up transport to use a TCP socket
2977 * @args: rpc transport creation arguments
2978 *
2979 */
2980static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2981{
2982 struct sockaddr *addr = args->dstaddr;
2983 struct rpc_xprt *xprt;
2984 struct sock_xprt *transport;
2985 struct rpc_xprt *ret;
2986 unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
2987
2988 if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
2989 max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
2990
2991 xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2992 max_slot_table_size);
2993 if (IS_ERR(xprt))
2994 return xprt;
2995 transport = container_of(xprt, struct sock_xprt, xprt);
2996
2997 xprt->prot = IPPROTO_TCP;
2998 xprt->xprt_class = &xs_tcp_transport;
2999 xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3000
3001 xprt->bind_timeout = XS_BIND_TO;
3002 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
3003 xprt->idle_timeout = XS_IDLE_DISC_TO;
3004
3005 xprt->ops = &xs_tcp_ops;
3006 xprt->timeout = &xs_tcp_default_timeout;
3007
3008 xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
3009 xprt->connect_timeout = xprt->timeout->to_initval *
3010 (xprt->timeout->to_retries + 1);
3011
3012 INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
3013 INIT_WORK(&transport->error_worker, xs_error_handle);
3014 INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
3015
3016 switch (addr->sa_family) {
3017 case AF_INET:
3018 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3019 xprt_set_bound(xprt);
3020
3021 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
3022 break;
3023 case AF_INET6:
3024 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3025 xprt_set_bound(xprt);
3026
3027 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
3028 break;
3029 default:
3030 ret = ERR_PTR(-EAFNOSUPPORT);
3031 goto out_err;
3032 }
3033
3034 if (xprt_bound(xprt))
3035 dprintk("RPC: set up xprt to %s (port %s) via %s\n",
3036 xprt->address_strings[RPC_DISPLAY_ADDR],
3037 xprt->address_strings[RPC_DISPLAY_PORT],
3038 xprt->address_strings[RPC_DISPLAY_PROTO]);
3039 else
3040 dprintk("RPC: set up xprt to %s (autobind) via %s\n",
3041 xprt->address_strings[RPC_DISPLAY_ADDR],
3042 xprt->address_strings[RPC_DISPLAY_PROTO]);
3043
3044 if (try_module_get(THIS_MODULE))
3045 return xprt;
3046 ret = ERR_PTR(-EINVAL);
3047out_err:
3048 xs_xprt_free(xprt);
3049 return ret;
3050}
3051
3052/**
3053 * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
3054 * @args: rpc transport creation arguments
3055 *
3056 */
3057static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
3058{
3059 struct sockaddr *addr = args->dstaddr;
3060 struct rpc_xprt *xprt;
3061 struct sock_xprt *transport;
3062 struct svc_sock *bc_sock;
3063 struct rpc_xprt *ret;
3064
3065 xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3066 xprt_tcp_slot_table_entries);
3067 if (IS_ERR(xprt))
3068 return xprt;
3069 transport = container_of(xprt, struct sock_xprt, xprt);
3070
3071 xprt->prot = IPPROTO_TCP;
3072 xprt->xprt_class = &xs_bc_tcp_transport;
3073 xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3074 xprt->timeout = &xs_tcp_default_timeout;
3075
3076 /* backchannel */
3077 xprt_set_bound(xprt);
3078 xprt->bind_timeout = 0;
3079 xprt->reestablish_timeout = 0;
3080 xprt->idle_timeout = 0;
3081
3082 xprt->ops = &bc_tcp_ops;
3083
3084 switch (addr->sa_family) {
3085 case AF_INET:
3086 xs_format_peer_addresses(xprt, "tcp",
3087 RPCBIND_NETID_TCP);
3088 break;
3089 case AF_INET6:
3090 xs_format_peer_addresses(xprt, "tcp",
3091 RPCBIND_NETID_TCP6);
3092 break;
3093 default:
3094 ret = ERR_PTR(-EAFNOSUPPORT);
3095 goto out_err;
3096 }
3097
3098 dprintk("RPC: set up xprt to %s (port %s) via %s\n",
3099 xprt->address_strings[RPC_DISPLAY_ADDR],
3100 xprt->address_strings[RPC_DISPLAY_PORT],
3101 xprt->address_strings[RPC_DISPLAY_PROTO]);
3102
3103 /*
3104 * Once we've associated a backchannel xprt with a connection,
3105 * we want to keep it around as long as the connection lasts,
3106 * in case we need to start using it for a backchannel again;
3107 * this reference won't be dropped until bc_xprt is destroyed.
3108 */
3109 xprt_get(xprt);
3110 args->bc_xprt->xpt_bc_xprt = xprt;
3111 xprt->bc_xprt = args->bc_xprt;
3112 bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3113 transport->sock = bc_sock->sk_sock;
3114 transport->inet = bc_sock->sk_sk;
3115
3116 /*
3117 * Since we don't want connections for the backchannel, we set
3118 * the xprt status to connected
3119 */
3120 xprt_set_connected(xprt);
3121
3122 if (try_module_get(THIS_MODULE))
3123 return xprt;
3124
3125 args->bc_xprt->xpt_bc_xprt = NULL;
3126 args->bc_xprt->xpt_bc_xps = NULL;
3127 xprt_put(xprt);
3128 ret = ERR_PTR(-EINVAL);
3129out_err:
3130 xs_xprt_free(xprt);
3131 return ret;
3132}
3133
3134static struct xprt_class xs_local_transport = {
3135 .list = LIST_HEAD_INIT(xs_local_transport.list),
3136 .name = "named UNIX socket",
3137 .owner = THIS_MODULE,
3138 .ident = XPRT_TRANSPORT_LOCAL,
3139 .setup = xs_setup_local,
3140 .netid = { "" },
3141};
3142
3143static struct xprt_class xs_udp_transport = {
3144 .list = LIST_HEAD_INIT(xs_udp_transport.list),
3145 .name = "udp",
3146 .owner = THIS_MODULE,
3147 .ident = XPRT_TRANSPORT_UDP,
3148 .setup = xs_setup_udp,
3149 .netid = { "udp", "udp6", "" },
3150};
3151
3152static struct xprt_class xs_tcp_transport = {
3153 .list = LIST_HEAD_INIT(xs_tcp_transport.list),
3154 .name = "tcp",
3155 .owner = THIS_MODULE,
3156 .ident = XPRT_TRANSPORT_TCP,
3157 .setup = xs_setup_tcp,
3158 .netid = { "tcp", "tcp6", "" },
3159};
3160
3161static struct xprt_class xs_bc_tcp_transport = {
3162 .list = LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3163 .name = "tcp NFSv4.1 backchannel",
3164 .owner = THIS_MODULE,
3165 .ident = XPRT_TRANSPORT_BC_TCP,
3166 .setup = xs_setup_bc_tcp,
3167 .netid = { "" },
3168};
3169
3170/**
3171 * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3172 *
3173 */
3174int init_socket_xprt(void)
3175{
3176 if (!sunrpc_table_header)
3177 sunrpc_table_header = register_sysctl_table(sunrpc_table);
3178
3179 xprt_register_transport(&xs_local_transport);
3180 xprt_register_transport(&xs_udp_transport);
3181 xprt_register_transport(&xs_tcp_transport);
3182 xprt_register_transport(&xs_bc_tcp_transport);
3183
3184 return 0;
3185}
3186
3187/**
3188 * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3189 *
3190 */
3191void cleanup_socket_xprt(void)
3192{
3193 if (sunrpc_table_header) {
3194 unregister_sysctl_table(sunrpc_table_header);
3195 sunrpc_table_header = NULL;
3196 }
3197
3198 xprt_unregister_transport(&xs_local_transport);
3199 xprt_unregister_transport(&xs_udp_transport);
3200 xprt_unregister_transport(&xs_tcp_transport);
3201 xprt_unregister_transport(&xs_bc_tcp_transport);
3202}
3203
3204static int param_set_portnr(const char *val, const struct kernel_param *kp)
3205{
3206 return param_set_uint_minmax(val, kp,
3207 RPC_MIN_RESVPORT,
3208 RPC_MAX_RESVPORT);
3209}
3210
3211static const struct kernel_param_ops param_ops_portnr = {
3212 .set = param_set_portnr,
3213 .get = param_get_uint,
3214};
3215
3216#define param_check_portnr(name, p) \
3217 __param_check(name, p, unsigned int);
3218
3219module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3220module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3221
3222static int param_set_slot_table_size(const char *val,
3223 const struct kernel_param *kp)
3224{
3225 return param_set_uint_minmax(val, kp,
3226 RPC_MIN_SLOT_TABLE,
3227 RPC_MAX_SLOT_TABLE);
3228}
3229
3230static const struct kernel_param_ops param_ops_slot_table_size = {
3231 .set = param_set_slot_table_size,
3232 .get = param_get_uint,
3233};
3234
3235#define param_check_slot_table_size(name, p) \
3236 __param_check(name, p, unsigned int);
3237
3238static int param_set_max_slot_table_size(const char *val,
3239 const struct kernel_param *kp)
3240{
3241 return param_set_uint_minmax(val, kp,
3242 RPC_MIN_SLOT_TABLE,
3243 RPC_MAX_SLOT_TABLE_LIMIT);
3244}
3245
3246static const struct kernel_param_ops param_ops_max_slot_table_size = {
3247 .set = param_set_max_slot_table_size,
3248 .get = param_get_uint,
3249};
3250
3251#define param_check_max_slot_table_size(name, p) \
3252 __param_check(name, p, unsigned int);
3253
3254module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3255 slot_table_size, 0644);
3256module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3257 max_slot_table_size, 0644);
3258module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3259 slot_table_size, 0644);
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 <linux/bvec.h>
51#include <linux/highmem.h>
52#include <linux/uio.h>
53#include <linux/sched/mm.h>
54
55#include <trace/events/sunrpc.h>
56
57#include "sunrpc.h"
58
59static void xs_close(struct rpc_xprt *xprt);
60static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
61 struct socket *sock);
62
63/*
64 * xprtsock tunables
65 */
66static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
67static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
68static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
69
70static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
71static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
72
73#define XS_TCP_LINGER_TO (15U * HZ)
74static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
75
76/*
77 * We can register our own files under /proc/sys/sunrpc by
78 * calling register_sysctl_table() again. The files in that
79 * directory become the union of all files registered there.
80 *
81 * We simply need to make sure that we don't collide with
82 * someone else's file names!
83 */
84
85static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
86static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
87static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
88static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
89static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
90
91static struct ctl_table_header *sunrpc_table_header;
92
93/*
94 * FIXME: changing the UDP slot table size should also resize the UDP
95 * socket buffers for existing UDP transports
96 */
97static struct ctl_table xs_tunables_table[] = {
98 {
99 .procname = "udp_slot_table_entries",
100 .data = &xprt_udp_slot_table_entries,
101 .maxlen = sizeof(unsigned int),
102 .mode = 0644,
103 .proc_handler = proc_dointvec_minmax,
104 .extra1 = &min_slot_table_size,
105 .extra2 = &max_slot_table_size
106 },
107 {
108 .procname = "tcp_slot_table_entries",
109 .data = &xprt_tcp_slot_table_entries,
110 .maxlen = sizeof(unsigned int),
111 .mode = 0644,
112 .proc_handler = proc_dointvec_minmax,
113 .extra1 = &min_slot_table_size,
114 .extra2 = &max_slot_table_size
115 },
116 {
117 .procname = "tcp_max_slot_table_entries",
118 .data = &xprt_max_tcp_slot_table_entries,
119 .maxlen = sizeof(unsigned int),
120 .mode = 0644,
121 .proc_handler = proc_dointvec_minmax,
122 .extra1 = &min_slot_table_size,
123 .extra2 = &max_tcp_slot_table_limit
124 },
125 {
126 .procname = "min_resvport",
127 .data = &xprt_min_resvport,
128 .maxlen = sizeof(unsigned int),
129 .mode = 0644,
130 .proc_handler = proc_dointvec_minmax,
131 .extra1 = &xprt_min_resvport_limit,
132 .extra2 = &xprt_max_resvport_limit
133 },
134 {
135 .procname = "max_resvport",
136 .data = &xprt_max_resvport,
137 .maxlen = sizeof(unsigned int),
138 .mode = 0644,
139 .proc_handler = proc_dointvec_minmax,
140 .extra1 = &xprt_min_resvport_limit,
141 .extra2 = &xprt_max_resvport_limit
142 },
143 {
144 .procname = "tcp_fin_timeout",
145 .data = &xs_tcp_fin_timeout,
146 .maxlen = sizeof(xs_tcp_fin_timeout),
147 .mode = 0644,
148 .proc_handler = proc_dointvec_jiffies,
149 },
150 { },
151};
152
153static struct ctl_table sunrpc_table[] = {
154 {
155 .procname = "sunrpc",
156 .mode = 0555,
157 .child = xs_tunables_table
158 },
159 { },
160};
161
162/*
163 * Wait duration for a reply from the RPC portmapper.
164 */
165#define XS_BIND_TO (60U * HZ)
166
167/*
168 * Delay if a UDP socket connect error occurs. This is most likely some
169 * kind of resource problem on the local host.
170 */
171#define XS_UDP_REEST_TO (2U * HZ)
172
173/*
174 * The reestablish timeout allows clients to delay for a bit before attempting
175 * to reconnect to a server that just dropped our connection.
176 *
177 * We implement an exponential backoff when trying to reestablish a TCP
178 * transport connection with the server. Some servers like to drop a TCP
179 * connection when they are overworked, so we start with a short timeout and
180 * increase over time if the server is down or not responding.
181 */
182#define XS_TCP_INIT_REEST_TO (3U * HZ)
183
184/*
185 * TCP idle timeout; client drops the transport socket if it is idle
186 * for this long. Note that we also timeout UDP sockets to prevent
187 * holding port numbers when there is no RPC traffic.
188 */
189#define XS_IDLE_DISC_TO (5U * 60 * HZ)
190
191#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
192# undef RPC_DEBUG_DATA
193# define RPCDBG_FACILITY RPCDBG_TRANS
194#endif
195
196#ifdef RPC_DEBUG_DATA
197static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
198{
199 u8 *buf = (u8 *) packet;
200 int j;
201
202 dprintk("RPC: %s\n", msg);
203 for (j = 0; j < count && j < 128; j += 4) {
204 if (!(j & 31)) {
205 if (j)
206 dprintk("\n");
207 dprintk("0x%04x ", j);
208 }
209 dprintk("%02x%02x%02x%02x ",
210 buf[j], buf[j+1], buf[j+2], buf[j+3]);
211 }
212 dprintk("\n");
213}
214#else
215static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
216{
217 /* NOP */
218}
219#endif
220
221static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
222{
223 return (struct rpc_xprt *) sk->sk_user_data;
224}
225
226static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
227{
228 return (struct sockaddr *) &xprt->addr;
229}
230
231static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
232{
233 return (struct sockaddr_un *) &xprt->addr;
234}
235
236static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
237{
238 return (struct sockaddr_in *) &xprt->addr;
239}
240
241static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
242{
243 return (struct sockaddr_in6 *) &xprt->addr;
244}
245
246static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
247{
248 struct sockaddr *sap = xs_addr(xprt);
249 struct sockaddr_in6 *sin6;
250 struct sockaddr_in *sin;
251 struct sockaddr_un *sun;
252 char buf[128];
253
254 switch (sap->sa_family) {
255 case AF_LOCAL:
256 sun = xs_addr_un(xprt);
257 strlcpy(buf, sun->sun_path, sizeof(buf));
258 xprt->address_strings[RPC_DISPLAY_ADDR] =
259 kstrdup(buf, GFP_KERNEL);
260 break;
261 case AF_INET:
262 (void)rpc_ntop(sap, buf, sizeof(buf));
263 xprt->address_strings[RPC_DISPLAY_ADDR] =
264 kstrdup(buf, GFP_KERNEL);
265 sin = xs_addr_in(xprt);
266 snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
267 break;
268 case AF_INET6:
269 (void)rpc_ntop(sap, buf, sizeof(buf));
270 xprt->address_strings[RPC_DISPLAY_ADDR] =
271 kstrdup(buf, GFP_KERNEL);
272 sin6 = xs_addr_in6(xprt);
273 snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
274 break;
275 default:
276 BUG();
277 }
278
279 xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
280}
281
282static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
283{
284 struct sockaddr *sap = xs_addr(xprt);
285 char buf[128];
286
287 snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
288 xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
289
290 snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
291 xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
292}
293
294static void xs_format_peer_addresses(struct rpc_xprt *xprt,
295 const char *protocol,
296 const char *netid)
297{
298 xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
299 xprt->address_strings[RPC_DISPLAY_NETID] = netid;
300 xs_format_common_peer_addresses(xprt);
301 xs_format_common_peer_ports(xprt);
302}
303
304static void xs_update_peer_port(struct rpc_xprt *xprt)
305{
306 kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
307 kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
308
309 xs_format_common_peer_ports(xprt);
310}
311
312static void xs_free_peer_addresses(struct rpc_xprt *xprt)
313{
314 unsigned int i;
315
316 for (i = 0; i < RPC_DISPLAY_MAX; i++)
317 switch (i) {
318 case RPC_DISPLAY_PROTO:
319 case RPC_DISPLAY_NETID:
320 continue;
321 default:
322 kfree(xprt->address_strings[i]);
323 }
324}
325
326static size_t
327xs_alloc_sparse_pages(struct xdr_buf *buf, size_t want, gfp_t gfp)
328{
329 size_t i,n;
330
331 if (!want || !(buf->flags & XDRBUF_SPARSE_PAGES))
332 return want;
333 n = (buf->page_base + want + PAGE_SIZE - 1) >> PAGE_SHIFT;
334 for (i = 0; i < n; i++) {
335 if (buf->pages[i])
336 continue;
337 buf->bvec[i].bv_page = buf->pages[i] = alloc_page(gfp);
338 if (!buf->pages[i]) {
339 i *= PAGE_SIZE;
340 return i > buf->page_base ? i - buf->page_base : 0;
341 }
342 }
343 return want;
344}
345
346static ssize_t
347xs_sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags, size_t seek)
348{
349 ssize_t ret;
350 if (seek != 0)
351 iov_iter_advance(&msg->msg_iter, seek);
352 ret = sock_recvmsg(sock, msg, flags);
353 return ret > 0 ? ret + seek : ret;
354}
355
356static ssize_t
357xs_read_kvec(struct socket *sock, struct msghdr *msg, int flags,
358 struct kvec *kvec, size_t count, size_t seek)
359{
360 iov_iter_kvec(&msg->msg_iter, READ, kvec, 1, count);
361 return xs_sock_recvmsg(sock, msg, flags, seek);
362}
363
364static ssize_t
365xs_read_bvec(struct socket *sock, struct msghdr *msg, int flags,
366 struct bio_vec *bvec, unsigned long nr, size_t count,
367 size_t seek)
368{
369 iov_iter_bvec(&msg->msg_iter, READ, bvec, nr, count);
370 return xs_sock_recvmsg(sock, msg, flags, seek);
371}
372
373static ssize_t
374xs_read_discard(struct socket *sock, struct msghdr *msg, int flags,
375 size_t count)
376{
377 iov_iter_discard(&msg->msg_iter, READ, count);
378 return sock_recvmsg(sock, msg, flags);
379}
380
381#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
382static void
383xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
384{
385 struct bvec_iter bi = {
386 .bi_size = count,
387 };
388 struct bio_vec bv;
389
390 bvec_iter_advance(bvec, &bi, seek & PAGE_MASK);
391 for_each_bvec(bv, bvec, bi, bi)
392 flush_dcache_page(bv.bv_page);
393}
394#else
395static inline void
396xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
397{
398}
399#endif
400
401static ssize_t
402xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags,
403 struct xdr_buf *buf, size_t count, size_t seek, size_t *read)
404{
405 size_t want, seek_init = seek, offset = 0;
406 ssize_t ret;
407
408 want = min_t(size_t, count, buf->head[0].iov_len);
409 if (seek < want) {
410 ret = xs_read_kvec(sock, msg, flags, &buf->head[0], want, seek);
411 if (ret <= 0)
412 goto sock_err;
413 offset += ret;
414 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
415 goto out;
416 if (ret != want)
417 goto out;
418 seek = 0;
419 } else {
420 seek -= want;
421 offset += want;
422 }
423
424 want = xs_alloc_sparse_pages(buf,
425 min_t(size_t, count - offset, buf->page_len),
426 GFP_KERNEL);
427 if (seek < want) {
428 ret = xs_read_bvec(sock, msg, flags, buf->bvec,
429 xdr_buf_pagecount(buf),
430 want + buf->page_base,
431 seek + buf->page_base);
432 if (ret <= 0)
433 goto sock_err;
434 xs_flush_bvec(buf->bvec, ret, seek + buf->page_base);
435 offset += ret - buf->page_base;
436 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
437 goto out;
438 if (ret != want)
439 goto out;
440 seek = 0;
441 } else {
442 seek -= want;
443 offset += want;
444 }
445
446 want = min_t(size_t, count - offset, buf->tail[0].iov_len);
447 if (seek < want) {
448 ret = xs_read_kvec(sock, msg, flags, &buf->tail[0], want, seek);
449 if (ret <= 0)
450 goto sock_err;
451 offset += ret;
452 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
453 goto out;
454 if (ret != want)
455 goto out;
456 } else if (offset < seek_init)
457 offset = seek_init;
458 ret = -EMSGSIZE;
459out:
460 *read = offset - seek_init;
461 return ret;
462sock_err:
463 offset += seek;
464 goto out;
465}
466
467static void
468xs_read_header(struct sock_xprt *transport, struct xdr_buf *buf)
469{
470 if (!transport->recv.copied) {
471 if (buf->head[0].iov_len >= transport->recv.offset)
472 memcpy(buf->head[0].iov_base,
473 &transport->recv.xid,
474 transport->recv.offset);
475 transport->recv.copied = transport->recv.offset;
476 }
477}
478
479static bool
480xs_read_stream_request_done(struct sock_xprt *transport)
481{
482 return transport->recv.fraghdr & cpu_to_be32(RPC_LAST_STREAM_FRAGMENT);
483}
484
485static void
486xs_read_stream_check_eor(struct sock_xprt *transport,
487 struct msghdr *msg)
488{
489 if (xs_read_stream_request_done(transport))
490 msg->msg_flags |= MSG_EOR;
491}
492
493static ssize_t
494xs_read_stream_request(struct sock_xprt *transport, struct msghdr *msg,
495 int flags, struct rpc_rqst *req)
496{
497 struct xdr_buf *buf = &req->rq_private_buf;
498 size_t want, uninitialized_var(read);
499 ssize_t uninitialized_var(ret);
500
501 xs_read_header(transport, buf);
502
503 want = transport->recv.len - transport->recv.offset;
504 if (want != 0) {
505 ret = xs_read_xdr_buf(transport->sock, msg, flags, buf,
506 transport->recv.copied + want,
507 transport->recv.copied,
508 &read);
509 transport->recv.offset += read;
510 transport->recv.copied += read;
511 }
512
513 if (transport->recv.offset == transport->recv.len)
514 xs_read_stream_check_eor(transport, msg);
515
516 if (want == 0)
517 return 0;
518
519 switch (ret) {
520 default:
521 break;
522 case -EFAULT:
523 case -EMSGSIZE:
524 msg->msg_flags |= MSG_TRUNC;
525 return read;
526 case 0:
527 return -ESHUTDOWN;
528 }
529 return ret < 0 ? ret : read;
530}
531
532static size_t
533xs_read_stream_headersize(bool isfrag)
534{
535 if (isfrag)
536 return sizeof(__be32);
537 return 3 * sizeof(__be32);
538}
539
540static ssize_t
541xs_read_stream_header(struct sock_xprt *transport, struct msghdr *msg,
542 int flags, size_t want, size_t seek)
543{
544 struct kvec kvec = {
545 .iov_base = &transport->recv.fraghdr,
546 .iov_len = want,
547 };
548 return xs_read_kvec(transport->sock, msg, flags, &kvec, want, seek);
549}
550
551#if defined(CONFIG_SUNRPC_BACKCHANNEL)
552static ssize_t
553xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
554{
555 struct rpc_xprt *xprt = &transport->xprt;
556 struct rpc_rqst *req;
557 ssize_t ret;
558
559 /* Look up and lock the request corresponding to the given XID */
560 req = xprt_lookup_bc_request(xprt, transport->recv.xid);
561 if (!req) {
562 printk(KERN_WARNING "Callback slot table overflowed\n");
563 return -ESHUTDOWN;
564 }
565 if (transport->recv.copied && !req->rq_private_buf.len)
566 return -ESHUTDOWN;
567
568 ret = xs_read_stream_request(transport, msg, flags, req);
569 if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
570 xprt_complete_bc_request(req, transport->recv.copied);
571 else
572 req->rq_private_buf.len = transport->recv.copied;
573
574 return ret;
575}
576#else /* CONFIG_SUNRPC_BACKCHANNEL */
577static ssize_t
578xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
579{
580 return -ESHUTDOWN;
581}
582#endif /* CONFIG_SUNRPC_BACKCHANNEL */
583
584static ssize_t
585xs_read_stream_reply(struct sock_xprt *transport, struct msghdr *msg, int flags)
586{
587 struct rpc_xprt *xprt = &transport->xprt;
588 struct rpc_rqst *req;
589 ssize_t ret = 0;
590
591 /* Look up and lock the request corresponding to the given XID */
592 spin_lock(&xprt->queue_lock);
593 req = xprt_lookup_rqst(xprt, transport->recv.xid);
594 if (!req || (transport->recv.copied && !req->rq_private_buf.len)) {
595 msg->msg_flags |= MSG_TRUNC;
596 goto out;
597 }
598 xprt_pin_rqst(req);
599 spin_unlock(&xprt->queue_lock);
600
601 ret = xs_read_stream_request(transport, msg, flags, req);
602
603 spin_lock(&xprt->queue_lock);
604 if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
605 xprt_complete_rqst(req->rq_task, transport->recv.copied);
606 else
607 req->rq_private_buf.len = transport->recv.copied;
608 xprt_unpin_rqst(req);
609out:
610 spin_unlock(&xprt->queue_lock);
611 return ret;
612}
613
614static ssize_t
615xs_read_stream(struct sock_xprt *transport, int flags)
616{
617 struct msghdr msg = { 0 };
618 size_t want, read = 0;
619 ssize_t ret = 0;
620
621 if (transport->recv.len == 0) {
622 want = xs_read_stream_headersize(transport->recv.copied != 0);
623 ret = xs_read_stream_header(transport, &msg, flags, want,
624 transport->recv.offset);
625 if (ret <= 0)
626 goto out_err;
627 transport->recv.offset = ret;
628 if (transport->recv.offset != want)
629 return transport->recv.offset;
630 transport->recv.len = be32_to_cpu(transport->recv.fraghdr) &
631 RPC_FRAGMENT_SIZE_MASK;
632 transport->recv.offset -= sizeof(transport->recv.fraghdr);
633 read = ret;
634 }
635
636 switch (be32_to_cpu(transport->recv.calldir)) {
637 default:
638 msg.msg_flags |= MSG_TRUNC;
639 break;
640 case RPC_CALL:
641 ret = xs_read_stream_call(transport, &msg, flags);
642 break;
643 case RPC_REPLY:
644 ret = xs_read_stream_reply(transport, &msg, flags);
645 }
646 if (msg.msg_flags & MSG_TRUNC) {
647 transport->recv.calldir = cpu_to_be32(-1);
648 transport->recv.copied = -1;
649 }
650 if (ret < 0)
651 goto out_err;
652 read += ret;
653 if (transport->recv.offset < transport->recv.len) {
654 if (!(msg.msg_flags & MSG_TRUNC))
655 return read;
656 msg.msg_flags = 0;
657 ret = xs_read_discard(transport->sock, &msg, flags,
658 transport->recv.len - transport->recv.offset);
659 if (ret <= 0)
660 goto out_err;
661 transport->recv.offset += ret;
662 read += ret;
663 if (transport->recv.offset != transport->recv.len)
664 return read;
665 }
666 if (xs_read_stream_request_done(transport)) {
667 trace_xs_stream_read_request(transport);
668 transport->recv.copied = 0;
669 }
670 transport->recv.offset = 0;
671 transport->recv.len = 0;
672 return read;
673out_err:
674 return ret != 0 ? ret : -ESHUTDOWN;
675}
676
677static __poll_t xs_poll_socket(struct sock_xprt *transport)
678{
679 return transport->sock->ops->poll(transport->file, transport->sock,
680 NULL);
681}
682
683static bool xs_poll_socket_readable(struct sock_xprt *transport)
684{
685 __poll_t events = xs_poll_socket(transport);
686
687 return (events & (EPOLLIN | EPOLLRDNORM)) && !(events & EPOLLRDHUP);
688}
689
690static void xs_poll_check_readable(struct sock_xprt *transport)
691{
692
693 clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
694 if (!xs_poll_socket_readable(transport))
695 return;
696 if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
697 queue_work(xprtiod_workqueue, &transport->recv_worker);
698}
699
700static void xs_stream_data_receive(struct sock_xprt *transport)
701{
702 size_t read = 0;
703 ssize_t ret = 0;
704
705 mutex_lock(&transport->recv_mutex);
706 if (transport->sock == NULL)
707 goto out;
708 for (;;) {
709 ret = xs_read_stream(transport, MSG_DONTWAIT);
710 if (ret < 0)
711 break;
712 read += ret;
713 cond_resched();
714 }
715 if (ret == -ESHUTDOWN)
716 kernel_sock_shutdown(transport->sock, SHUT_RDWR);
717 else
718 xs_poll_check_readable(transport);
719out:
720 mutex_unlock(&transport->recv_mutex);
721 trace_xs_stream_read_data(&transport->xprt, ret, read);
722}
723
724static void xs_stream_data_receive_workfn(struct work_struct *work)
725{
726 struct sock_xprt *transport =
727 container_of(work, struct sock_xprt, recv_worker);
728 unsigned int pflags = memalloc_nofs_save();
729
730 xs_stream_data_receive(transport);
731 memalloc_nofs_restore(pflags);
732}
733
734static void
735xs_stream_reset_connect(struct sock_xprt *transport)
736{
737 transport->recv.offset = 0;
738 transport->recv.len = 0;
739 transport->recv.copied = 0;
740 transport->xmit.offset = 0;
741}
742
743static void
744xs_stream_start_connect(struct sock_xprt *transport)
745{
746 transport->xprt.stat.connect_count++;
747 transport->xprt.stat.connect_start = jiffies;
748}
749
750#define XS_SENDMSG_FLAGS (MSG_DONTWAIT | MSG_NOSIGNAL)
751
752static int xs_sendmsg(struct socket *sock, struct msghdr *msg, size_t seek)
753{
754 if (seek)
755 iov_iter_advance(&msg->msg_iter, seek);
756 return sock_sendmsg(sock, msg);
757}
758
759static int xs_send_kvec(struct socket *sock, struct msghdr *msg, struct kvec *vec, size_t seek)
760{
761 iov_iter_kvec(&msg->msg_iter, WRITE, vec, 1, vec->iov_len);
762 return xs_sendmsg(sock, msg, seek);
763}
764
765static int xs_send_pagedata(struct socket *sock, struct msghdr *msg, struct xdr_buf *xdr, size_t base)
766{
767 int err;
768
769 err = xdr_alloc_bvec(xdr, GFP_KERNEL);
770 if (err < 0)
771 return err;
772
773 iov_iter_bvec(&msg->msg_iter, WRITE, xdr->bvec,
774 xdr_buf_pagecount(xdr),
775 xdr->page_len + xdr->page_base);
776 return xs_sendmsg(sock, msg, base + xdr->page_base);
777}
778
779#define xs_record_marker_len() sizeof(rpc_fraghdr)
780
781/* Common case:
782 * - stream transport
783 * - sending from byte 0 of the message
784 * - the message is wholly contained in @xdr's head iovec
785 */
786static int xs_send_rm_and_kvec(struct socket *sock, struct msghdr *msg,
787 rpc_fraghdr marker, struct kvec *vec, size_t base)
788{
789 struct kvec iov[2] = {
790 [0] = {
791 .iov_base = &marker,
792 .iov_len = sizeof(marker)
793 },
794 [1] = *vec,
795 };
796 size_t len = iov[0].iov_len + iov[1].iov_len;
797
798 iov_iter_kvec(&msg->msg_iter, WRITE, iov, 2, len);
799 return xs_sendmsg(sock, msg, base);
800}
801
802/**
803 * xs_sendpages - write pages directly to a socket
804 * @sock: socket to send on
805 * @addr: UDP only -- address of destination
806 * @addrlen: UDP only -- length of destination address
807 * @xdr: buffer containing this request
808 * @base: starting position in the buffer
809 * @rm: stream record marker field
810 * @sent_p: return the total number of bytes successfully queued for sending
811 *
812 */
813static int xs_sendpages(struct socket *sock, struct sockaddr *addr, int addrlen, struct xdr_buf *xdr, unsigned int base, rpc_fraghdr rm, int *sent_p)
814{
815 struct msghdr msg = {
816 .msg_name = addr,
817 .msg_namelen = addrlen,
818 .msg_flags = XS_SENDMSG_FLAGS | MSG_MORE,
819 };
820 unsigned int rmsize = rm ? sizeof(rm) : 0;
821 unsigned int remainder = rmsize + xdr->len - base;
822 unsigned int want;
823 int err = 0;
824
825 if (unlikely(!sock))
826 return -ENOTSOCK;
827
828 want = xdr->head[0].iov_len + rmsize;
829 if (base < want) {
830 unsigned int len = want - base;
831 remainder -= len;
832 if (remainder == 0)
833 msg.msg_flags &= ~MSG_MORE;
834 if (rmsize)
835 err = xs_send_rm_and_kvec(sock, &msg, rm,
836 &xdr->head[0], base);
837 else
838 err = xs_send_kvec(sock, &msg, &xdr->head[0], base);
839 if (remainder == 0 || err != len)
840 goto out;
841 *sent_p += err;
842 base = 0;
843 } else
844 base -= want;
845
846 if (base < xdr->page_len) {
847 unsigned int len = xdr->page_len - base;
848 remainder -= len;
849 if (remainder == 0)
850 msg.msg_flags &= ~MSG_MORE;
851 err = xs_send_pagedata(sock, &msg, xdr, base);
852 if (remainder == 0 || err != len)
853 goto out;
854 *sent_p += err;
855 base = 0;
856 } else
857 base -= xdr->page_len;
858
859 if (base >= xdr->tail[0].iov_len)
860 return 0;
861 msg.msg_flags &= ~MSG_MORE;
862 err = xs_send_kvec(sock, &msg, &xdr->tail[0], base);
863out:
864 if (err > 0) {
865 *sent_p += err;
866 err = 0;
867 }
868 return err;
869}
870
871/**
872 * xs_nospace - handle transmit was incomplete
873 * @req: pointer to RPC request
874 *
875 */
876static int xs_nospace(struct rpc_rqst *req)
877{
878 struct rpc_xprt *xprt = req->rq_xprt;
879 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
880 struct sock *sk = transport->inet;
881 int ret = -EAGAIN;
882
883 dprintk("RPC: %5u xmit incomplete (%u left of %u)\n",
884 req->rq_task->tk_pid,
885 req->rq_slen - transport->xmit.offset,
886 req->rq_slen);
887
888 /* Protect against races with write_space */
889 spin_lock(&xprt->transport_lock);
890
891 /* Don't race with disconnect */
892 if (xprt_connected(xprt)) {
893 /* wait for more buffer space */
894 sk->sk_write_pending++;
895 xprt_wait_for_buffer_space(xprt);
896 } else
897 ret = -ENOTCONN;
898
899 spin_unlock(&xprt->transport_lock);
900
901 /* Race breaker in case memory is freed before above code is called */
902 if (ret == -EAGAIN) {
903 struct socket_wq *wq;
904
905 rcu_read_lock();
906 wq = rcu_dereference(sk->sk_wq);
907 set_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags);
908 rcu_read_unlock();
909
910 sk->sk_write_space(sk);
911 }
912 return ret;
913}
914
915static void
916xs_stream_prepare_request(struct rpc_rqst *req)
917{
918 xdr_free_bvec(&req->rq_rcv_buf);
919 req->rq_task->tk_status = xdr_alloc_bvec(&req->rq_rcv_buf, GFP_KERNEL);
920}
921
922/*
923 * Determine if the previous message in the stream was aborted before it
924 * could complete transmission.
925 */
926static bool
927xs_send_request_was_aborted(struct sock_xprt *transport, struct rpc_rqst *req)
928{
929 return transport->xmit.offset != 0 && req->rq_bytes_sent == 0;
930}
931
932/*
933 * Return the stream record marker field for a record of length < 2^31-1
934 */
935static rpc_fraghdr
936xs_stream_record_marker(struct xdr_buf *xdr)
937{
938 if (!xdr->len)
939 return 0;
940 return cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | (u32)xdr->len);
941}
942
943/**
944 * xs_local_send_request - write an RPC request to an AF_LOCAL socket
945 * @req: pointer to RPC request
946 *
947 * Return values:
948 * 0: The request has been sent
949 * EAGAIN: The socket was blocked, please call again later to
950 * complete the request
951 * ENOTCONN: Caller needs to invoke connect logic then call again
952 * other: Some other error occured, the request was not sent
953 */
954static int xs_local_send_request(struct rpc_rqst *req)
955{
956 struct rpc_xprt *xprt = req->rq_xprt;
957 struct sock_xprt *transport =
958 container_of(xprt, struct sock_xprt, xprt);
959 struct xdr_buf *xdr = &req->rq_snd_buf;
960 rpc_fraghdr rm = xs_stream_record_marker(xdr);
961 unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
962 int status;
963 int sent = 0;
964
965 /* Close the stream if the previous transmission was incomplete */
966 if (xs_send_request_was_aborted(transport, req)) {
967 xs_close(xprt);
968 return -ENOTCONN;
969 }
970
971 xs_pktdump("packet data:",
972 req->rq_svec->iov_base, req->rq_svec->iov_len);
973
974 req->rq_xtime = ktime_get();
975 status = xs_sendpages(transport->sock, NULL, 0, xdr,
976 transport->xmit.offset, rm, &sent);
977 dprintk("RPC: %s(%u) = %d\n",
978 __func__, xdr->len - transport->xmit.offset, status);
979
980 if (status == -EAGAIN && sock_writeable(transport->inet))
981 status = -ENOBUFS;
982
983 if (likely(sent > 0) || status == 0) {
984 transport->xmit.offset += sent;
985 req->rq_bytes_sent = transport->xmit.offset;
986 if (likely(req->rq_bytes_sent >= msglen)) {
987 req->rq_xmit_bytes_sent += transport->xmit.offset;
988 transport->xmit.offset = 0;
989 return 0;
990 }
991 status = -EAGAIN;
992 }
993
994 switch (status) {
995 case -ENOBUFS:
996 break;
997 case -EAGAIN:
998 status = xs_nospace(req);
999 break;
1000 default:
1001 dprintk("RPC: sendmsg returned unrecognized error %d\n",
1002 -status);
1003 /* fall through */
1004 case -EPIPE:
1005 xs_close(xprt);
1006 status = -ENOTCONN;
1007 }
1008
1009 return status;
1010}
1011
1012/**
1013 * xs_udp_send_request - write an RPC request to a UDP socket
1014 * @req: pointer to RPC request
1015 *
1016 * Return values:
1017 * 0: The request has been sent
1018 * EAGAIN: The socket was blocked, please call again later to
1019 * complete the request
1020 * ENOTCONN: Caller needs to invoke connect logic then call again
1021 * other: Some other error occurred, the request was not sent
1022 */
1023static int xs_udp_send_request(struct rpc_rqst *req)
1024{
1025 struct rpc_xprt *xprt = req->rq_xprt;
1026 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1027 struct xdr_buf *xdr = &req->rq_snd_buf;
1028 int sent = 0;
1029 int status;
1030
1031 xs_pktdump("packet data:",
1032 req->rq_svec->iov_base,
1033 req->rq_svec->iov_len);
1034
1035 if (!xprt_bound(xprt))
1036 return -ENOTCONN;
1037
1038 if (!xprt_request_get_cong(xprt, req))
1039 return -EBADSLT;
1040
1041 req->rq_xtime = ktime_get();
1042 status = xs_sendpages(transport->sock, xs_addr(xprt), xprt->addrlen,
1043 xdr, 0, 0, &sent);
1044
1045 dprintk("RPC: xs_udp_send_request(%u) = %d\n",
1046 xdr->len, status);
1047
1048 /* firewall is blocking us, don't return -EAGAIN or we end up looping */
1049 if (status == -EPERM)
1050 goto process_status;
1051
1052 if (status == -EAGAIN && sock_writeable(transport->inet))
1053 status = -ENOBUFS;
1054
1055 if (sent > 0 || status == 0) {
1056 req->rq_xmit_bytes_sent += sent;
1057 if (sent >= req->rq_slen)
1058 return 0;
1059 /* Still some bytes left; set up for a retry later. */
1060 status = -EAGAIN;
1061 }
1062
1063process_status:
1064 switch (status) {
1065 case -ENOTSOCK:
1066 status = -ENOTCONN;
1067 /* Should we call xs_close() here? */
1068 break;
1069 case -EAGAIN:
1070 status = xs_nospace(req);
1071 break;
1072 case -ENETUNREACH:
1073 case -ENOBUFS:
1074 case -EPIPE:
1075 case -ECONNREFUSED:
1076 case -EPERM:
1077 /* When the server has died, an ICMP port unreachable message
1078 * prompts ECONNREFUSED. */
1079 break;
1080 default:
1081 dprintk("RPC: sendmsg returned unrecognized error %d\n",
1082 -status);
1083 }
1084
1085 return status;
1086}
1087
1088/**
1089 * xs_tcp_send_request - write an RPC request to a TCP socket
1090 * @req: pointer to RPC request
1091 *
1092 * Return values:
1093 * 0: The request has been sent
1094 * EAGAIN: The socket was blocked, please call again later to
1095 * complete the request
1096 * ENOTCONN: Caller needs to invoke connect logic then call again
1097 * other: Some other error occurred, the request was not sent
1098 *
1099 * XXX: In the case of soft timeouts, should we eventually give up
1100 * if sendmsg is not able to make progress?
1101 */
1102static int xs_tcp_send_request(struct rpc_rqst *req)
1103{
1104 struct rpc_xprt *xprt = req->rq_xprt;
1105 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1106 struct xdr_buf *xdr = &req->rq_snd_buf;
1107 rpc_fraghdr rm = xs_stream_record_marker(xdr);
1108 unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
1109 bool vm_wait = false;
1110 int status;
1111 int sent;
1112
1113 /* Close the stream if the previous transmission was incomplete */
1114 if (xs_send_request_was_aborted(transport, req)) {
1115 if (transport->sock != NULL)
1116 kernel_sock_shutdown(transport->sock, SHUT_RDWR);
1117 return -ENOTCONN;
1118 }
1119
1120 xs_pktdump("packet data:",
1121 req->rq_svec->iov_base,
1122 req->rq_svec->iov_len);
1123
1124 if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state))
1125 xs_tcp_set_socket_timeouts(xprt, transport->sock);
1126
1127 /* Continue transmitting the packet/record. We must be careful
1128 * to cope with writespace callbacks arriving _after_ we have
1129 * called sendmsg(). */
1130 req->rq_xtime = ktime_get();
1131 while (1) {
1132 sent = 0;
1133 status = xs_sendpages(transport->sock, NULL, 0, xdr,
1134 transport->xmit.offset, rm, &sent);
1135
1136 dprintk("RPC: xs_tcp_send_request(%u) = %d\n",
1137 xdr->len - transport->xmit.offset, status);
1138
1139 /* If we've sent the entire packet, immediately
1140 * reset the count of bytes sent. */
1141 transport->xmit.offset += sent;
1142 req->rq_bytes_sent = transport->xmit.offset;
1143 if (likely(req->rq_bytes_sent >= msglen)) {
1144 req->rq_xmit_bytes_sent += transport->xmit.offset;
1145 transport->xmit.offset = 0;
1146 return 0;
1147 }
1148
1149 WARN_ON_ONCE(sent == 0 && status == 0);
1150
1151 if (status == -EAGAIN ) {
1152 /*
1153 * Return EAGAIN if we're sure we're hitting the
1154 * socket send buffer limits.
1155 */
1156 if (test_bit(SOCK_NOSPACE, &transport->sock->flags))
1157 break;
1158 /*
1159 * Did we hit a memory allocation failure?
1160 */
1161 if (sent == 0) {
1162 status = -ENOBUFS;
1163 if (vm_wait)
1164 break;
1165 /* Retry, knowing now that we're below the
1166 * socket send buffer limit
1167 */
1168 vm_wait = true;
1169 }
1170 continue;
1171 }
1172 if (status < 0)
1173 break;
1174 vm_wait = false;
1175 }
1176
1177 switch (status) {
1178 case -ENOTSOCK:
1179 status = -ENOTCONN;
1180 /* Should we call xs_close() here? */
1181 break;
1182 case -EAGAIN:
1183 status = xs_nospace(req);
1184 break;
1185 case -ECONNRESET:
1186 case -ECONNREFUSED:
1187 case -ENOTCONN:
1188 case -EADDRINUSE:
1189 case -ENOBUFS:
1190 case -EPIPE:
1191 break;
1192 default:
1193 dprintk("RPC: sendmsg returned unrecognized error %d\n",
1194 -status);
1195 }
1196
1197 return status;
1198}
1199
1200static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1201{
1202 transport->old_data_ready = sk->sk_data_ready;
1203 transport->old_state_change = sk->sk_state_change;
1204 transport->old_write_space = sk->sk_write_space;
1205 transport->old_error_report = sk->sk_error_report;
1206}
1207
1208static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1209{
1210 sk->sk_data_ready = transport->old_data_ready;
1211 sk->sk_state_change = transport->old_state_change;
1212 sk->sk_write_space = transport->old_write_space;
1213 sk->sk_error_report = transport->old_error_report;
1214}
1215
1216static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
1217{
1218 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1219
1220 clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1221 clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state);
1222 clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state);
1223 clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state);
1224}
1225
1226static void xs_run_error_worker(struct sock_xprt *transport, unsigned int nr)
1227{
1228 set_bit(nr, &transport->sock_state);
1229 queue_work(xprtiod_workqueue, &transport->error_worker);
1230}
1231
1232static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
1233{
1234 smp_mb__before_atomic();
1235 clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1236 clear_bit(XPRT_CLOSING, &xprt->state);
1237 xs_sock_reset_state_flags(xprt);
1238 smp_mb__after_atomic();
1239}
1240
1241/**
1242 * xs_error_report - callback to handle TCP socket state errors
1243 * @sk: socket
1244 *
1245 * Note: we don't call sock_error() since there may be a rpc_task
1246 * using the socket, and so we don't want to clear sk->sk_err.
1247 */
1248static void xs_error_report(struct sock *sk)
1249{
1250 struct sock_xprt *transport;
1251 struct rpc_xprt *xprt;
1252
1253 read_lock_bh(&sk->sk_callback_lock);
1254 if (!(xprt = xprt_from_sock(sk)))
1255 goto out;
1256
1257 transport = container_of(xprt, struct sock_xprt, xprt);
1258 transport->xprt_err = -sk->sk_err;
1259 if (transport->xprt_err == 0)
1260 goto out;
1261 dprintk("RPC: xs_error_report client %p, error=%d...\n",
1262 xprt, -transport->xprt_err);
1263 trace_rpc_socket_error(xprt, sk->sk_socket, transport->xprt_err);
1264
1265 /* barrier ensures xprt_err is set before XPRT_SOCK_WAKE_ERROR */
1266 smp_mb__before_atomic();
1267 xs_run_error_worker(transport, XPRT_SOCK_WAKE_ERROR);
1268 out:
1269 read_unlock_bh(&sk->sk_callback_lock);
1270}
1271
1272static void xs_reset_transport(struct sock_xprt *transport)
1273{
1274 struct socket *sock = transport->sock;
1275 struct sock *sk = transport->inet;
1276 struct rpc_xprt *xprt = &transport->xprt;
1277 struct file *filp = transport->file;
1278
1279 if (sk == NULL)
1280 return;
1281
1282 if (atomic_read(&transport->xprt.swapper))
1283 sk_clear_memalloc(sk);
1284
1285 kernel_sock_shutdown(sock, SHUT_RDWR);
1286
1287 mutex_lock(&transport->recv_mutex);
1288 write_lock_bh(&sk->sk_callback_lock);
1289 transport->inet = NULL;
1290 transport->sock = NULL;
1291 transport->file = NULL;
1292
1293 sk->sk_user_data = NULL;
1294
1295 xs_restore_old_callbacks(transport, sk);
1296 xprt_clear_connected(xprt);
1297 write_unlock_bh(&sk->sk_callback_lock);
1298 xs_sock_reset_connection_flags(xprt);
1299 /* Reset stream record info */
1300 xs_stream_reset_connect(transport);
1301 mutex_unlock(&transport->recv_mutex);
1302
1303 trace_rpc_socket_close(xprt, sock);
1304 fput(filp);
1305
1306 xprt_disconnect_done(xprt);
1307}
1308
1309/**
1310 * xs_close - close a socket
1311 * @xprt: transport
1312 *
1313 * This is used when all requests are complete; ie, no DRC state remains
1314 * on the server we want to save.
1315 *
1316 * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
1317 * xs_reset_transport() zeroing the socket from underneath a writer.
1318 */
1319static void xs_close(struct rpc_xprt *xprt)
1320{
1321 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1322
1323 dprintk("RPC: xs_close xprt %p\n", xprt);
1324
1325 xs_reset_transport(transport);
1326 xprt->reestablish_timeout = 0;
1327}
1328
1329static void xs_inject_disconnect(struct rpc_xprt *xprt)
1330{
1331 dprintk("RPC: injecting transport disconnect on xprt=%p\n",
1332 xprt);
1333 xprt_disconnect_done(xprt);
1334}
1335
1336static void xs_xprt_free(struct rpc_xprt *xprt)
1337{
1338 xs_free_peer_addresses(xprt);
1339 xprt_free(xprt);
1340}
1341
1342/**
1343 * xs_destroy - prepare to shutdown a transport
1344 * @xprt: doomed transport
1345 *
1346 */
1347static void xs_destroy(struct rpc_xprt *xprt)
1348{
1349 struct sock_xprt *transport = container_of(xprt,
1350 struct sock_xprt, xprt);
1351 dprintk("RPC: xs_destroy xprt %p\n", xprt);
1352
1353 cancel_delayed_work_sync(&transport->connect_worker);
1354 xs_close(xprt);
1355 cancel_work_sync(&transport->recv_worker);
1356 cancel_work_sync(&transport->error_worker);
1357 xs_xprt_free(xprt);
1358 module_put(THIS_MODULE);
1359}
1360
1361/**
1362 * xs_udp_data_read_skb - receive callback for UDP sockets
1363 * @xprt: transport
1364 * @sk: socket
1365 * @skb: skbuff
1366 *
1367 */
1368static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
1369 struct sock *sk,
1370 struct sk_buff *skb)
1371{
1372 struct rpc_task *task;
1373 struct rpc_rqst *rovr;
1374 int repsize, copied;
1375 u32 _xid;
1376 __be32 *xp;
1377
1378 repsize = skb->len;
1379 if (repsize < 4) {
1380 dprintk("RPC: impossible RPC reply size %d!\n", repsize);
1381 return;
1382 }
1383
1384 /* Copy the XID from the skb... */
1385 xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
1386 if (xp == NULL)
1387 return;
1388
1389 /* Look up and lock the request corresponding to the given XID */
1390 spin_lock(&xprt->queue_lock);
1391 rovr = xprt_lookup_rqst(xprt, *xp);
1392 if (!rovr)
1393 goto out_unlock;
1394 xprt_pin_rqst(rovr);
1395 xprt_update_rtt(rovr->rq_task);
1396 spin_unlock(&xprt->queue_lock);
1397 task = rovr->rq_task;
1398
1399 if ((copied = rovr->rq_private_buf.buflen) > repsize)
1400 copied = repsize;
1401
1402 /* Suck it into the iovec, verify checksum if not done by hw. */
1403 if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1404 spin_lock(&xprt->queue_lock);
1405 __UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
1406 goto out_unpin;
1407 }
1408
1409
1410 spin_lock(&xprt->transport_lock);
1411 xprt_adjust_cwnd(xprt, task, copied);
1412 spin_unlock(&xprt->transport_lock);
1413 spin_lock(&xprt->queue_lock);
1414 xprt_complete_rqst(task, copied);
1415 __UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
1416out_unpin:
1417 xprt_unpin_rqst(rovr);
1418 out_unlock:
1419 spin_unlock(&xprt->queue_lock);
1420}
1421
1422static void xs_udp_data_receive(struct sock_xprt *transport)
1423{
1424 struct sk_buff *skb;
1425 struct sock *sk;
1426 int err;
1427
1428 mutex_lock(&transport->recv_mutex);
1429 sk = transport->inet;
1430 if (sk == NULL)
1431 goto out;
1432 for (;;) {
1433 skb = skb_recv_udp(sk, 0, 1, &err);
1434 if (skb == NULL)
1435 break;
1436 xs_udp_data_read_skb(&transport->xprt, sk, skb);
1437 consume_skb(skb);
1438 cond_resched();
1439 }
1440 xs_poll_check_readable(transport);
1441out:
1442 mutex_unlock(&transport->recv_mutex);
1443}
1444
1445static void xs_udp_data_receive_workfn(struct work_struct *work)
1446{
1447 struct sock_xprt *transport =
1448 container_of(work, struct sock_xprt, recv_worker);
1449 unsigned int pflags = memalloc_nofs_save();
1450
1451 xs_udp_data_receive(transport);
1452 memalloc_nofs_restore(pflags);
1453}
1454
1455/**
1456 * xs_data_ready - "data ready" callback for UDP sockets
1457 * @sk: socket with data to read
1458 *
1459 */
1460static void xs_data_ready(struct sock *sk)
1461{
1462 struct rpc_xprt *xprt;
1463
1464 read_lock_bh(&sk->sk_callback_lock);
1465 dprintk("RPC: xs_data_ready...\n");
1466 xprt = xprt_from_sock(sk);
1467 if (xprt != NULL) {
1468 struct sock_xprt *transport = container_of(xprt,
1469 struct sock_xprt, xprt);
1470 transport->old_data_ready(sk);
1471 /* Any data means we had a useful conversation, so
1472 * then we don't need to delay the next reconnect
1473 */
1474 if (xprt->reestablish_timeout)
1475 xprt->reestablish_timeout = 0;
1476 if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1477 queue_work(xprtiod_workqueue, &transport->recv_worker);
1478 }
1479 read_unlock_bh(&sk->sk_callback_lock);
1480}
1481
1482/*
1483 * Helper function to force a TCP close if the server is sending
1484 * junk and/or it has put us in CLOSE_WAIT
1485 */
1486static void xs_tcp_force_close(struct rpc_xprt *xprt)
1487{
1488 xprt_force_disconnect(xprt);
1489}
1490
1491#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1492static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
1493{
1494 return PAGE_SIZE;
1495}
1496#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1497
1498/**
1499 * xs_tcp_state_change - callback to handle TCP socket state changes
1500 * @sk: socket whose state has changed
1501 *
1502 */
1503static void xs_tcp_state_change(struct sock *sk)
1504{
1505 struct rpc_xprt *xprt;
1506 struct sock_xprt *transport;
1507
1508 read_lock_bh(&sk->sk_callback_lock);
1509 if (!(xprt = xprt_from_sock(sk)))
1510 goto out;
1511 dprintk("RPC: xs_tcp_state_change client %p...\n", xprt);
1512 dprintk("RPC: state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1513 sk->sk_state, xprt_connected(xprt),
1514 sock_flag(sk, SOCK_DEAD),
1515 sock_flag(sk, SOCK_ZAPPED),
1516 sk->sk_shutdown);
1517
1518 transport = container_of(xprt, struct sock_xprt, xprt);
1519 trace_rpc_socket_state_change(xprt, sk->sk_socket);
1520 switch (sk->sk_state) {
1521 case TCP_ESTABLISHED:
1522 if (!xprt_test_and_set_connected(xprt)) {
1523 xprt->connect_cookie++;
1524 clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
1525 xprt_clear_connecting(xprt);
1526
1527 xprt->stat.connect_count++;
1528 xprt->stat.connect_time += (long)jiffies -
1529 xprt->stat.connect_start;
1530 xs_run_error_worker(transport, XPRT_SOCK_WAKE_PENDING);
1531 }
1532 break;
1533 case TCP_FIN_WAIT1:
1534 /* The client initiated a shutdown of the socket */
1535 xprt->connect_cookie++;
1536 xprt->reestablish_timeout = 0;
1537 set_bit(XPRT_CLOSING, &xprt->state);
1538 smp_mb__before_atomic();
1539 clear_bit(XPRT_CONNECTED, &xprt->state);
1540 clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1541 smp_mb__after_atomic();
1542 break;
1543 case TCP_CLOSE_WAIT:
1544 /* The server initiated a shutdown of the socket */
1545 xprt->connect_cookie++;
1546 clear_bit(XPRT_CONNECTED, &xprt->state);
1547 xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1548 /* fall through */
1549 case TCP_CLOSING:
1550 /*
1551 * If the server closed down the connection, make sure that
1552 * we back off before reconnecting
1553 */
1554 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1555 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1556 break;
1557 case TCP_LAST_ACK:
1558 set_bit(XPRT_CLOSING, &xprt->state);
1559 smp_mb__before_atomic();
1560 clear_bit(XPRT_CONNECTED, &xprt->state);
1561 smp_mb__after_atomic();
1562 break;
1563 case TCP_CLOSE:
1564 if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
1565 &transport->sock_state))
1566 xprt_clear_connecting(xprt);
1567 clear_bit(XPRT_CLOSING, &xprt->state);
1568 /* Trigger the socket release */
1569 xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1570 }
1571 out:
1572 read_unlock_bh(&sk->sk_callback_lock);
1573}
1574
1575static void xs_write_space(struct sock *sk)
1576{
1577 struct socket_wq *wq;
1578 struct sock_xprt *transport;
1579 struct rpc_xprt *xprt;
1580
1581 if (!sk->sk_socket)
1582 return;
1583 clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1584
1585 if (unlikely(!(xprt = xprt_from_sock(sk))))
1586 return;
1587 transport = container_of(xprt, struct sock_xprt, xprt);
1588 rcu_read_lock();
1589 wq = rcu_dereference(sk->sk_wq);
1590 if (!wq || test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags) == 0)
1591 goto out;
1592
1593 xs_run_error_worker(transport, XPRT_SOCK_WAKE_WRITE);
1594 sk->sk_write_pending--;
1595out:
1596 rcu_read_unlock();
1597}
1598
1599/**
1600 * xs_udp_write_space - callback invoked when socket buffer space
1601 * becomes available
1602 * @sk: socket whose state has changed
1603 *
1604 * Called when more output buffer space is available for this socket.
1605 * We try not to wake our writers until they can make "significant"
1606 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1607 * with a bunch of small requests.
1608 */
1609static void xs_udp_write_space(struct sock *sk)
1610{
1611 read_lock_bh(&sk->sk_callback_lock);
1612
1613 /* from net/core/sock.c:sock_def_write_space */
1614 if (sock_writeable(sk))
1615 xs_write_space(sk);
1616
1617 read_unlock_bh(&sk->sk_callback_lock);
1618}
1619
1620/**
1621 * xs_tcp_write_space - callback invoked when socket buffer space
1622 * becomes available
1623 * @sk: socket whose state has changed
1624 *
1625 * Called when more output buffer space is available for this socket.
1626 * We try not to wake our writers until they can make "significant"
1627 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1628 * with a bunch of small requests.
1629 */
1630static void xs_tcp_write_space(struct sock *sk)
1631{
1632 read_lock_bh(&sk->sk_callback_lock);
1633
1634 /* from net/core/stream.c:sk_stream_write_space */
1635 if (sk_stream_is_writeable(sk))
1636 xs_write_space(sk);
1637
1638 read_unlock_bh(&sk->sk_callback_lock);
1639}
1640
1641static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1642{
1643 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1644 struct sock *sk = transport->inet;
1645
1646 if (transport->rcvsize) {
1647 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1648 sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1649 }
1650 if (transport->sndsize) {
1651 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1652 sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1653 sk->sk_write_space(sk);
1654 }
1655}
1656
1657/**
1658 * xs_udp_set_buffer_size - set send and receive limits
1659 * @xprt: generic transport
1660 * @sndsize: requested size of send buffer, in bytes
1661 * @rcvsize: requested size of receive buffer, in bytes
1662 *
1663 * Set socket send and receive buffer size limits.
1664 */
1665static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1666{
1667 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1668
1669 transport->sndsize = 0;
1670 if (sndsize)
1671 transport->sndsize = sndsize + 1024;
1672 transport->rcvsize = 0;
1673 if (rcvsize)
1674 transport->rcvsize = rcvsize + 1024;
1675
1676 xs_udp_do_set_buffer_size(xprt);
1677}
1678
1679/**
1680 * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1681 * @xprt: controlling transport
1682 * @task: task that timed out
1683 *
1684 * Adjust the congestion window after a retransmit timeout has occurred.
1685 */
1686static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1687{
1688 spin_lock(&xprt->transport_lock);
1689 xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1690 spin_unlock(&xprt->transport_lock);
1691}
1692
1693static int xs_get_random_port(void)
1694{
1695 unsigned short min = xprt_min_resvport, max = xprt_max_resvport;
1696 unsigned short range;
1697 unsigned short rand;
1698
1699 if (max < min)
1700 return -EADDRINUSE;
1701 range = max - min + 1;
1702 rand = (unsigned short) prandom_u32() % range;
1703 return rand + min;
1704}
1705
1706/**
1707 * xs_set_reuseaddr_port - set the socket's port and address reuse options
1708 * @sock: socket
1709 *
1710 * Note that this function has to be called on all sockets that share the
1711 * same port, and it must be called before binding.
1712 */
1713static void xs_sock_set_reuseport(struct socket *sock)
1714{
1715 int opt = 1;
1716
1717 kernel_setsockopt(sock, SOL_SOCKET, SO_REUSEPORT,
1718 (char *)&opt, sizeof(opt));
1719}
1720
1721static unsigned short xs_sock_getport(struct socket *sock)
1722{
1723 struct sockaddr_storage buf;
1724 unsigned short port = 0;
1725
1726 if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0)
1727 goto out;
1728 switch (buf.ss_family) {
1729 case AF_INET6:
1730 port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1731 break;
1732 case AF_INET:
1733 port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1734 }
1735out:
1736 return port;
1737}
1738
1739/**
1740 * xs_set_port - reset the port number in the remote endpoint address
1741 * @xprt: generic transport
1742 * @port: new port number
1743 *
1744 */
1745static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1746{
1747 dprintk("RPC: setting port for xprt %p to %u\n", xprt, port);
1748
1749 rpc_set_port(xs_addr(xprt), port);
1750 xs_update_peer_port(xprt);
1751}
1752
1753static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1754{
1755 if (transport->srcport == 0)
1756 transport->srcport = xs_sock_getport(sock);
1757}
1758
1759static int xs_get_srcport(struct sock_xprt *transport)
1760{
1761 int port = transport->srcport;
1762
1763 if (port == 0 && transport->xprt.resvport)
1764 port = xs_get_random_port();
1765 return port;
1766}
1767
1768static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1769{
1770 if (transport->srcport != 0)
1771 transport->srcport = 0;
1772 if (!transport->xprt.resvport)
1773 return 0;
1774 if (port <= xprt_min_resvport || port > xprt_max_resvport)
1775 return xprt_max_resvport;
1776 return --port;
1777}
1778static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1779{
1780 struct sockaddr_storage myaddr;
1781 int err, nloop = 0;
1782 int port = xs_get_srcport(transport);
1783 unsigned short last;
1784
1785 /*
1786 * If we are asking for any ephemeral port (i.e. port == 0 &&
1787 * transport->xprt.resvport == 0), don't bind. Let the local
1788 * port selection happen implicitly when the socket is used
1789 * (for example at connect time).
1790 *
1791 * This ensures that we can continue to establish TCP
1792 * connections even when all local ephemeral ports are already
1793 * a part of some TCP connection. This makes no difference
1794 * for UDP sockets, but also doens't harm them.
1795 *
1796 * If we're asking for any reserved port (i.e. port == 0 &&
1797 * transport->xprt.resvport == 1) xs_get_srcport above will
1798 * ensure that port is non-zero and we will bind as needed.
1799 */
1800 if (port <= 0)
1801 return port;
1802
1803 memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1804 do {
1805 rpc_set_port((struct sockaddr *)&myaddr, port);
1806 err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1807 transport->xprt.addrlen);
1808 if (err == 0) {
1809 transport->srcport = port;
1810 break;
1811 }
1812 last = port;
1813 port = xs_next_srcport(transport, port);
1814 if (port > last)
1815 nloop++;
1816 } while (err == -EADDRINUSE && nloop != 2);
1817
1818 if (myaddr.ss_family == AF_INET)
1819 dprintk("RPC: %s %pI4:%u: %s (%d)\n", __func__,
1820 &((struct sockaddr_in *)&myaddr)->sin_addr,
1821 port, err ? "failed" : "ok", err);
1822 else
1823 dprintk("RPC: %s %pI6:%u: %s (%d)\n", __func__,
1824 &((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1825 port, err ? "failed" : "ok", err);
1826 return err;
1827}
1828
1829/*
1830 * We don't support autobind on AF_LOCAL sockets
1831 */
1832static void xs_local_rpcbind(struct rpc_task *task)
1833{
1834 xprt_set_bound(task->tk_xprt);
1835}
1836
1837static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1838{
1839}
1840
1841#ifdef CONFIG_DEBUG_LOCK_ALLOC
1842static struct lock_class_key xs_key[2];
1843static struct lock_class_key xs_slock_key[2];
1844
1845static inline void xs_reclassify_socketu(struct socket *sock)
1846{
1847 struct sock *sk = sock->sk;
1848
1849 sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1850 &xs_slock_key[1], "sk_lock-AF_LOCAL-RPC", &xs_key[1]);
1851}
1852
1853static inline void xs_reclassify_socket4(struct socket *sock)
1854{
1855 struct sock *sk = sock->sk;
1856
1857 sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1858 &xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1859}
1860
1861static inline void xs_reclassify_socket6(struct socket *sock)
1862{
1863 struct sock *sk = sock->sk;
1864
1865 sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1866 &xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1867}
1868
1869static inline void xs_reclassify_socket(int family, struct socket *sock)
1870{
1871 if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
1872 return;
1873
1874 switch (family) {
1875 case AF_LOCAL:
1876 xs_reclassify_socketu(sock);
1877 break;
1878 case AF_INET:
1879 xs_reclassify_socket4(sock);
1880 break;
1881 case AF_INET6:
1882 xs_reclassify_socket6(sock);
1883 break;
1884 }
1885}
1886#else
1887static inline void xs_reclassify_socket(int family, struct socket *sock)
1888{
1889}
1890#endif
1891
1892static void xs_dummy_setup_socket(struct work_struct *work)
1893{
1894}
1895
1896static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1897 struct sock_xprt *transport, int family, int type,
1898 int protocol, bool reuseport)
1899{
1900 struct file *filp;
1901 struct socket *sock;
1902 int err;
1903
1904 err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1905 if (err < 0) {
1906 dprintk("RPC: can't create %d transport socket (%d).\n",
1907 protocol, -err);
1908 goto out;
1909 }
1910 xs_reclassify_socket(family, sock);
1911
1912 if (reuseport)
1913 xs_sock_set_reuseport(sock);
1914
1915 err = xs_bind(transport, sock);
1916 if (err) {
1917 sock_release(sock);
1918 goto out;
1919 }
1920
1921 filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1922 if (IS_ERR(filp))
1923 return ERR_CAST(filp);
1924 transport->file = filp;
1925
1926 return sock;
1927out:
1928 return ERR_PTR(err);
1929}
1930
1931static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1932 struct socket *sock)
1933{
1934 struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1935 xprt);
1936
1937 if (!transport->inet) {
1938 struct sock *sk = sock->sk;
1939
1940 write_lock_bh(&sk->sk_callback_lock);
1941
1942 xs_save_old_callbacks(transport, sk);
1943
1944 sk->sk_user_data = xprt;
1945 sk->sk_data_ready = xs_data_ready;
1946 sk->sk_write_space = xs_udp_write_space;
1947 sock_set_flag(sk, SOCK_FASYNC);
1948 sk->sk_error_report = xs_error_report;
1949
1950 xprt_clear_connected(xprt);
1951
1952 /* Reset to new socket */
1953 transport->sock = sock;
1954 transport->inet = sk;
1955
1956 write_unlock_bh(&sk->sk_callback_lock);
1957 }
1958
1959 xs_stream_start_connect(transport);
1960
1961 return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1962}
1963
1964/**
1965 * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1966 * @transport: socket transport to connect
1967 */
1968static int xs_local_setup_socket(struct sock_xprt *transport)
1969{
1970 struct rpc_xprt *xprt = &transport->xprt;
1971 struct file *filp;
1972 struct socket *sock;
1973 int status = -EIO;
1974
1975 status = __sock_create(xprt->xprt_net, AF_LOCAL,
1976 SOCK_STREAM, 0, &sock, 1);
1977 if (status < 0) {
1978 dprintk("RPC: can't create AF_LOCAL "
1979 "transport socket (%d).\n", -status);
1980 goto out;
1981 }
1982 xs_reclassify_socket(AF_LOCAL, sock);
1983
1984 filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1985 if (IS_ERR(filp)) {
1986 status = PTR_ERR(filp);
1987 goto out;
1988 }
1989 transport->file = filp;
1990
1991 dprintk("RPC: worker connecting xprt %p via AF_LOCAL to %s\n",
1992 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1993
1994 status = xs_local_finish_connecting(xprt, sock);
1995 trace_rpc_socket_connect(xprt, sock, status);
1996 switch (status) {
1997 case 0:
1998 dprintk("RPC: xprt %p connected to %s\n",
1999 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2000 xprt->stat.connect_count++;
2001 xprt->stat.connect_time += (long)jiffies -
2002 xprt->stat.connect_start;
2003 xprt_set_connected(xprt);
2004 case -ENOBUFS:
2005 break;
2006 case -ENOENT:
2007 dprintk("RPC: xprt %p: socket %s does not exist\n",
2008 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2009 break;
2010 case -ECONNREFUSED:
2011 dprintk("RPC: xprt %p: connection refused for %s\n",
2012 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2013 break;
2014 default:
2015 printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
2016 __func__, -status,
2017 xprt->address_strings[RPC_DISPLAY_ADDR]);
2018 }
2019
2020out:
2021 xprt_clear_connecting(xprt);
2022 xprt_wake_pending_tasks(xprt, status);
2023 return status;
2024}
2025
2026static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2027{
2028 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2029 int ret;
2030
2031 if (RPC_IS_ASYNC(task)) {
2032 /*
2033 * We want the AF_LOCAL connect to be resolved in the
2034 * filesystem namespace of the process making the rpc
2035 * call. Thus we connect synchronously.
2036 *
2037 * If we want to support asynchronous AF_LOCAL calls,
2038 * we'll need to figure out how to pass a namespace to
2039 * connect.
2040 */
2041 task->tk_rpc_status = -ENOTCONN;
2042 rpc_exit(task, -ENOTCONN);
2043 return;
2044 }
2045 ret = xs_local_setup_socket(transport);
2046 if (ret && !RPC_IS_SOFTCONN(task))
2047 msleep_interruptible(15000);
2048}
2049
2050#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
2051/*
2052 * Note that this should be called with XPRT_LOCKED held (or when we otherwise
2053 * know that we have exclusive access to the socket), to guard against
2054 * races with xs_reset_transport.
2055 */
2056static void xs_set_memalloc(struct rpc_xprt *xprt)
2057{
2058 struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
2059 xprt);
2060
2061 /*
2062 * If there's no sock, then we have nothing to set. The
2063 * reconnecting process will get it for us.
2064 */
2065 if (!transport->inet)
2066 return;
2067 if (atomic_read(&xprt->swapper))
2068 sk_set_memalloc(transport->inet);
2069}
2070
2071/**
2072 * xs_enable_swap - Tag this transport as being used for swap.
2073 * @xprt: transport to tag
2074 *
2075 * Take a reference to this transport on behalf of the rpc_clnt, and
2076 * optionally mark it for swapping if it wasn't already.
2077 */
2078static int
2079xs_enable_swap(struct rpc_xprt *xprt)
2080{
2081 struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2082
2083 if (atomic_inc_return(&xprt->swapper) != 1)
2084 return 0;
2085 if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2086 return -ERESTARTSYS;
2087 if (xs->inet)
2088 sk_set_memalloc(xs->inet);
2089 xprt_release_xprt(xprt, NULL);
2090 return 0;
2091}
2092
2093/**
2094 * xs_disable_swap - Untag this transport as being used for swap.
2095 * @xprt: transport to tag
2096 *
2097 * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
2098 * swapper refcount goes to 0, untag the socket as a memalloc socket.
2099 */
2100static void
2101xs_disable_swap(struct rpc_xprt *xprt)
2102{
2103 struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2104
2105 if (!atomic_dec_and_test(&xprt->swapper))
2106 return;
2107 if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2108 return;
2109 if (xs->inet)
2110 sk_clear_memalloc(xs->inet);
2111 xprt_release_xprt(xprt, NULL);
2112}
2113#else
2114static void xs_set_memalloc(struct rpc_xprt *xprt)
2115{
2116}
2117
2118static int
2119xs_enable_swap(struct rpc_xprt *xprt)
2120{
2121 return -EINVAL;
2122}
2123
2124static void
2125xs_disable_swap(struct rpc_xprt *xprt)
2126{
2127}
2128#endif
2129
2130static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2131{
2132 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2133
2134 if (!transport->inet) {
2135 struct sock *sk = sock->sk;
2136
2137 write_lock_bh(&sk->sk_callback_lock);
2138
2139 xs_save_old_callbacks(transport, sk);
2140
2141 sk->sk_user_data = xprt;
2142 sk->sk_data_ready = xs_data_ready;
2143 sk->sk_write_space = xs_udp_write_space;
2144 sock_set_flag(sk, SOCK_FASYNC);
2145
2146 xprt_set_connected(xprt);
2147
2148 /* Reset to new socket */
2149 transport->sock = sock;
2150 transport->inet = sk;
2151
2152 xs_set_memalloc(xprt);
2153
2154 write_unlock_bh(&sk->sk_callback_lock);
2155 }
2156 xs_udp_do_set_buffer_size(xprt);
2157
2158 xprt->stat.connect_start = jiffies;
2159}
2160
2161static void xs_udp_setup_socket(struct work_struct *work)
2162{
2163 struct sock_xprt *transport =
2164 container_of(work, struct sock_xprt, connect_worker.work);
2165 struct rpc_xprt *xprt = &transport->xprt;
2166 struct socket *sock;
2167 int status = -EIO;
2168
2169 sock = xs_create_sock(xprt, transport,
2170 xs_addr(xprt)->sa_family, SOCK_DGRAM,
2171 IPPROTO_UDP, false);
2172 if (IS_ERR(sock))
2173 goto out;
2174
2175 dprintk("RPC: worker connecting xprt %p via %s to "
2176 "%s (port %s)\n", xprt,
2177 xprt->address_strings[RPC_DISPLAY_PROTO],
2178 xprt->address_strings[RPC_DISPLAY_ADDR],
2179 xprt->address_strings[RPC_DISPLAY_PORT]);
2180
2181 xs_udp_finish_connecting(xprt, sock);
2182 trace_rpc_socket_connect(xprt, sock, 0);
2183 status = 0;
2184out:
2185 xprt_clear_connecting(xprt);
2186 xprt_unlock_connect(xprt, transport);
2187 xprt_wake_pending_tasks(xprt, status);
2188}
2189
2190/**
2191 * xs_tcp_shutdown - gracefully shut down a TCP socket
2192 * @xprt: transport
2193 *
2194 * Initiates a graceful shutdown of the TCP socket by calling the
2195 * equivalent of shutdown(SHUT_RDWR);
2196 */
2197static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2198{
2199 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2200 struct socket *sock = transport->sock;
2201 int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
2202
2203 if (sock == NULL)
2204 return;
2205 switch (skst) {
2206 default:
2207 kernel_sock_shutdown(sock, SHUT_RDWR);
2208 trace_rpc_socket_shutdown(xprt, sock);
2209 break;
2210 case TCP_CLOSE:
2211 case TCP_TIME_WAIT:
2212 xs_reset_transport(transport);
2213 }
2214}
2215
2216static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
2217 struct socket *sock)
2218{
2219 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2220 unsigned int keepidle;
2221 unsigned int keepcnt;
2222 unsigned int opt_on = 1;
2223 unsigned int timeo;
2224
2225 spin_lock(&xprt->transport_lock);
2226 keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
2227 keepcnt = xprt->timeout->to_retries + 1;
2228 timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2229 (xprt->timeout->to_retries + 1);
2230 clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2231 spin_unlock(&xprt->transport_lock);
2232
2233 /* TCP Keepalive options */
2234 kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
2235 (char *)&opt_on, sizeof(opt_on));
2236 kernel_setsockopt(sock, SOL_TCP, TCP_KEEPIDLE,
2237 (char *)&keepidle, sizeof(keepidle));
2238 kernel_setsockopt(sock, SOL_TCP, TCP_KEEPINTVL,
2239 (char *)&keepidle, sizeof(keepidle));
2240 kernel_setsockopt(sock, SOL_TCP, TCP_KEEPCNT,
2241 (char *)&keepcnt, sizeof(keepcnt));
2242
2243 /* TCP user timeout (see RFC5482) */
2244 kernel_setsockopt(sock, SOL_TCP, TCP_USER_TIMEOUT,
2245 (char *)&timeo, sizeof(timeo));
2246}
2247
2248static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
2249 unsigned long connect_timeout,
2250 unsigned long reconnect_timeout)
2251{
2252 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2253 struct rpc_timeout to;
2254 unsigned long initval;
2255
2256 spin_lock(&xprt->transport_lock);
2257 if (reconnect_timeout < xprt->max_reconnect_timeout)
2258 xprt->max_reconnect_timeout = reconnect_timeout;
2259 if (connect_timeout < xprt->connect_timeout) {
2260 memcpy(&to, xprt->timeout, sizeof(to));
2261 initval = DIV_ROUND_UP(connect_timeout, to.to_retries + 1);
2262 /* Arbitrary lower limit */
2263 if (initval < XS_TCP_INIT_REEST_TO << 1)
2264 initval = XS_TCP_INIT_REEST_TO << 1;
2265 to.to_initval = initval;
2266 to.to_maxval = initval;
2267 memcpy(&transport->tcp_timeout, &to,
2268 sizeof(transport->tcp_timeout));
2269 xprt->timeout = &transport->tcp_timeout;
2270 xprt->connect_timeout = connect_timeout;
2271 }
2272 set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2273 spin_unlock(&xprt->transport_lock);
2274}
2275
2276static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2277{
2278 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2279 int ret = -ENOTCONN;
2280
2281 if (!transport->inet) {
2282 struct sock *sk = sock->sk;
2283 unsigned int addr_pref = IPV6_PREFER_SRC_PUBLIC;
2284
2285 /* Avoid temporary address, they are bad for long-lived
2286 * connections such as NFS mounts.
2287 * RFC4941, section 3.6 suggests that:
2288 * Individual applications, which have specific
2289 * knowledge about the normal duration of connections,
2290 * MAY override this as appropriate.
2291 */
2292 kernel_setsockopt(sock, SOL_IPV6, IPV6_ADDR_PREFERENCES,
2293 (char *)&addr_pref, sizeof(addr_pref));
2294
2295 xs_tcp_set_socket_timeouts(xprt, sock);
2296
2297 write_lock_bh(&sk->sk_callback_lock);
2298
2299 xs_save_old_callbacks(transport, sk);
2300
2301 sk->sk_user_data = xprt;
2302 sk->sk_data_ready = xs_data_ready;
2303 sk->sk_state_change = xs_tcp_state_change;
2304 sk->sk_write_space = xs_tcp_write_space;
2305 sock_set_flag(sk, SOCK_FASYNC);
2306 sk->sk_error_report = xs_error_report;
2307
2308 /* socket options */
2309 sock_reset_flag(sk, SOCK_LINGER);
2310 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
2311
2312 xprt_clear_connected(xprt);
2313
2314 /* Reset to new socket */
2315 transport->sock = sock;
2316 transport->inet = sk;
2317
2318 write_unlock_bh(&sk->sk_callback_lock);
2319 }
2320
2321 if (!xprt_bound(xprt))
2322 goto out;
2323
2324 xs_set_memalloc(xprt);
2325
2326 xs_stream_start_connect(transport);
2327
2328 /* Tell the socket layer to start connecting... */
2329 set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2330 ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2331 switch (ret) {
2332 case 0:
2333 xs_set_srcport(transport, sock);
2334 /* fall through */
2335 case -EINPROGRESS:
2336 /* SYN_SENT! */
2337 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2338 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2339 break;
2340 case -EADDRNOTAVAIL:
2341 /* Source port number is unavailable. Try a new one! */
2342 transport->srcport = 0;
2343 }
2344out:
2345 return ret;
2346}
2347
2348/**
2349 * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2350 * @work: queued work item
2351 *
2352 * Invoked by a work queue tasklet.
2353 */
2354static void xs_tcp_setup_socket(struct work_struct *work)
2355{
2356 struct sock_xprt *transport =
2357 container_of(work, struct sock_xprt, connect_worker.work);
2358 struct socket *sock = transport->sock;
2359 struct rpc_xprt *xprt = &transport->xprt;
2360 int status = -EIO;
2361
2362 if (!sock) {
2363 sock = xs_create_sock(xprt, transport,
2364 xs_addr(xprt)->sa_family, SOCK_STREAM,
2365 IPPROTO_TCP, true);
2366 if (IS_ERR(sock)) {
2367 status = PTR_ERR(sock);
2368 goto out;
2369 }
2370 }
2371
2372 dprintk("RPC: worker connecting xprt %p via %s to "
2373 "%s (port %s)\n", xprt,
2374 xprt->address_strings[RPC_DISPLAY_PROTO],
2375 xprt->address_strings[RPC_DISPLAY_ADDR],
2376 xprt->address_strings[RPC_DISPLAY_PORT]);
2377
2378 status = xs_tcp_finish_connecting(xprt, sock);
2379 trace_rpc_socket_connect(xprt, sock, status);
2380 dprintk("RPC: %p connect status %d connected %d sock state %d\n",
2381 xprt, -status, xprt_connected(xprt),
2382 sock->sk->sk_state);
2383 switch (status) {
2384 default:
2385 printk("%s: connect returned unhandled error %d\n",
2386 __func__, status);
2387 /* fall through */
2388 case -EADDRNOTAVAIL:
2389 /* We're probably in TIME_WAIT. Get rid of existing socket,
2390 * and retry
2391 */
2392 xs_tcp_force_close(xprt);
2393 break;
2394 case 0:
2395 case -EINPROGRESS:
2396 case -EALREADY:
2397 xprt_unlock_connect(xprt, transport);
2398 return;
2399 case -EINVAL:
2400 /* Happens, for instance, if the user specified a link
2401 * local IPv6 address without a scope-id.
2402 */
2403 case -ECONNREFUSED:
2404 case -ECONNRESET:
2405 case -ENETDOWN:
2406 case -ENETUNREACH:
2407 case -EHOSTUNREACH:
2408 case -EADDRINUSE:
2409 case -ENOBUFS:
2410 /*
2411 * xs_tcp_force_close() wakes tasks with -EIO.
2412 * We need to wake them first to ensure the
2413 * correct error code.
2414 */
2415 xprt_wake_pending_tasks(xprt, status);
2416 xs_tcp_force_close(xprt);
2417 goto out;
2418 }
2419 status = -EAGAIN;
2420out:
2421 xprt_clear_connecting(xprt);
2422 xprt_unlock_connect(xprt, transport);
2423 xprt_wake_pending_tasks(xprt, status);
2424}
2425
2426/**
2427 * xs_connect - connect a socket to a remote endpoint
2428 * @xprt: pointer to transport structure
2429 * @task: address of RPC task that manages state of connect request
2430 *
2431 * TCP: If the remote end dropped the connection, delay reconnecting.
2432 *
2433 * UDP socket connects are synchronous, but we use a work queue anyway
2434 * to guarantee that even unprivileged user processes can set up a
2435 * socket on a privileged port.
2436 *
2437 * If a UDP socket connect fails, the delay behavior here prevents
2438 * retry floods (hard mounts).
2439 */
2440static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2441{
2442 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2443 unsigned long delay = 0;
2444
2445 WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2446
2447 if (transport->sock != NULL) {
2448 dprintk("RPC: xs_connect delayed xprt %p for %lu "
2449 "seconds\n",
2450 xprt, xprt->reestablish_timeout / HZ);
2451
2452 /* Start by resetting any existing state */
2453 xs_reset_transport(transport);
2454
2455 delay = xprt_reconnect_delay(xprt);
2456 xprt_reconnect_backoff(xprt, XS_TCP_INIT_REEST_TO);
2457
2458 } else
2459 dprintk("RPC: xs_connect scheduled xprt %p\n", xprt);
2460
2461 queue_delayed_work(xprtiod_workqueue,
2462 &transport->connect_worker,
2463 delay);
2464}
2465
2466static void xs_wake_disconnect(struct sock_xprt *transport)
2467{
2468 if (test_and_clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state))
2469 xs_tcp_force_close(&transport->xprt);
2470}
2471
2472static void xs_wake_write(struct sock_xprt *transport)
2473{
2474 if (test_and_clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state))
2475 xprt_write_space(&transport->xprt);
2476}
2477
2478static void xs_wake_error(struct sock_xprt *transport)
2479{
2480 int sockerr;
2481
2482 if (!test_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2483 return;
2484 mutex_lock(&transport->recv_mutex);
2485 if (transport->sock == NULL)
2486 goto out;
2487 if (!test_and_clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2488 goto out;
2489 sockerr = xchg(&transport->xprt_err, 0);
2490 if (sockerr < 0)
2491 xprt_wake_pending_tasks(&transport->xprt, sockerr);
2492out:
2493 mutex_unlock(&transport->recv_mutex);
2494}
2495
2496static void xs_wake_pending(struct sock_xprt *transport)
2497{
2498 if (test_and_clear_bit(XPRT_SOCK_WAKE_PENDING, &transport->sock_state))
2499 xprt_wake_pending_tasks(&transport->xprt, -EAGAIN);
2500}
2501
2502static void xs_error_handle(struct work_struct *work)
2503{
2504 struct sock_xprt *transport = container_of(work,
2505 struct sock_xprt, error_worker);
2506
2507 xs_wake_disconnect(transport);
2508 xs_wake_write(transport);
2509 xs_wake_error(transport);
2510 xs_wake_pending(transport);
2511}
2512
2513/**
2514 * xs_local_print_stats - display AF_LOCAL socket-specifc stats
2515 * @xprt: rpc_xprt struct containing statistics
2516 * @seq: output file
2517 *
2518 */
2519static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2520{
2521 long idle_time = 0;
2522
2523 if (xprt_connected(xprt))
2524 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2525
2526 seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2527 "%llu %llu %lu %llu %llu\n",
2528 xprt->stat.bind_count,
2529 xprt->stat.connect_count,
2530 xprt->stat.connect_time / HZ,
2531 idle_time,
2532 xprt->stat.sends,
2533 xprt->stat.recvs,
2534 xprt->stat.bad_xids,
2535 xprt->stat.req_u,
2536 xprt->stat.bklog_u,
2537 xprt->stat.max_slots,
2538 xprt->stat.sending_u,
2539 xprt->stat.pending_u);
2540}
2541
2542/**
2543 * xs_udp_print_stats - display UDP socket-specifc stats
2544 * @xprt: rpc_xprt struct containing statistics
2545 * @seq: output file
2546 *
2547 */
2548static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2549{
2550 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2551
2552 seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2553 "%lu %llu %llu\n",
2554 transport->srcport,
2555 xprt->stat.bind_count,
2556 xprt->stat.sends,
2557 xprt->stat.recvs,
2558 xprt->stat.bad_xids,
2559 xprt->stat.req_u,
2560 xprt->stat.bklog_u,
2561 xprt->stat.max_slots,
2562 xprt->stat.sending_u,
2563 xprt->stat.pending_u);
2564}
2565
2566/**
2567 * xs_tcp_print_stats - display TCP socket-specifc stats
2568 * @xprt: rpc_xprt struct containing statistics
2569 * @seq: output file
2570 *
2571 */
2572static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2573{
2574 struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2575 long idle_time = 0;
2576
2577 if (xprt_connected(xprt))
2578 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2579
2580 seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2581 "%llu %llu %lu %llu %llu\n",
2582 transport->srcport,
2583 xprt->stat.bind_count,
2584 xprt->stat.connect_count,
2585 xprt->stat.connect_time / HZ,
2586 idle_time,
2587 xprt->stat.sends,
2588 xprt->stat.recvs,
2589 xprt->stat.bad_xids,
2590 xprt->stat.req_u,
2591 xprt->stat.bklog_u,
2592 xprt->stat.max_slots,
2593 xprt->stat.sending_u,
2594 xprt->stat.pending_u);
2595}
2596
2597/*
2598 * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2599 * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2600 * to use the server side send routines.
2601 */
2602static int bc_malloc(struct rpc_task *task)
2603{
2604 struct rpc_rqst *rqst = task->tk_rqstp;
2605 size_t size = rqst->rq_callsize;
2606 struct page *page;
2607 struct rpc_buffer *buf;
2608
2609 if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2610 WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2611 size);
2612 return -EINVAL;
2613 }
2614
2615 page = alloc_page(GFP_KERNEL);
2616 if (!page)
2617 return -ENOMEM;
2618
2619 buf = page_address(page);
2620 buf->len = PAGE_SIZE;
2621
2622 rqst->rq_buffer = buf->data;
2623 rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2624 return 0;
2625}
2626
2627/*
2628 * Free the space allocated in the bc_alloc routine
2629 */
2630static void bc_free(struct rpc_task *task)
2631{
2632 void *buffer = task->tk_rqstp->rq_buffer;
2633 struct rpc_buffer *buf;
2634
2635 buf = container_of(buffer, struct rpc_buffer, data);
2636 free_page((unsigned long)buf);
2637}
2638
2639/*
2640 * Use the svc_sock to send the callback. Must be called with svsk->sk_mutex
2641 * held. Borrows heavily from svc_tcp_sendto and xs_tcp_send_request.
2642 */
2643static int bc_sendto(struct rpc_rqst *req)
2644{
2645 int len;
2646 struct xdr_buf *xbufp = &req->rq_snd_buf;
2647 struct sock_xprt *transport =
2648 container_of(req->rq_xprt, struct sock_xprt, xprt);
2649 unsigned long headoff;
2650 unsigned long tailoff;
2651 struct page *tailpage;
2652 struct msghdr msg = {
2653 .msg_flags = MSG_MORE
2654 };
2655 rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT |
2656 (u32)xbufp->len);
2657 struct kvec iov = {
2658 .iov_base = &marker,
2659 .iov_len = sizeof(marker),
2660 };
2661
2662 len = kernel_sendmsg(transport->sock, &msg, &iov, 1, iov.iov_len);
2663 if (len != iov.iov_len)
2664 return -EAGAIN;
2665
2666 tailpage = NULL;
2667 if (xbufp->tail[0].iov_len)
2668 tailpage = virt_to_page(xbufp->tail[0].iov_base);
2669 tailoff = (unsigned long)xbufp->tail[0].iov_base & ~PAGE_MASK;
2670 headoff = (unsigned long)xbufp->head[0].iov_base & ~PAGE_MASK;
2671 len = svc_send_common(transport->sock, xbufp,
2672 virt_to_page(xbufp->head[0].iov_base), headoff,
2673 tailpage, tailoff);
2674 if (len != xbufp->len)
2675 return -EAGAIN;
2676 return len;
2677}
2678
2679/*
2680 * The send routine. Borrows from svc_send
2681 */
2682static int bc_send_request(struct rpc_rqst *req)
2683{
2684 struct svc_xprt *xprt;
2685 int len;
2686
2687 dprintk("sending request with xid: %08x\n", ntohl(req->rq_xid));
2688 /*
2689 * Get the server socket associated with this callback xprt
2690 */
2691 xprt = req->rq_xprt->bc_xprt;
2692
2693 /*
2694 * Grab the mutex to serialize data as the connection is shared
2695 * with the fore channel
2696 */
2697 mutex_lock(&xprt->xpt_mutex);
2698 if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2699 len = -ENOTCONN;
2700 else
2701 len = bc_sendto(req);
2702 mutex_unlock(&xprt->xpt_mutex);
2703
2704 if (len > 0)
2705 len = 0;
2706
2707 return len;
2708}
2709
2710/*
2711 * The close routine. Since this is client initiated, we do nothing
2712 */
2713
2714static void bc_close(struct rpc_xprt *xprt)
2715{
2716}
2717
2718/*
2719 * The xprt destroy routine. Again, because this connection is client
2720 * initiated, we do nothing
2721 */
2722
2723static void bc_destroy(struct rpc_xprt *xprt)
2724{
2725 dprintk("RPC: bc_destroy xprt %p\n", xprt);
2726
2727 xs_xprt_free(xprt);
2728 module_put(THIS_MODULE);
2729}
2730
2731static const struct rpc_xprt_ops xs_local_ops = {
2732 .reserve_xprt = xprt_reserve_xprt,
2733 .release_xprt = xprt_release_xprt,
2734 .alloc_slot = xprt_alloc_slot,
2735 .free_slot = xprt_free_slot,
2736 .rpcbind = xs_local_rpcbind,
2737 .set_port = xs_local_set_port,
2738 .connect = xs_local_connect,
2739 .buf_alloc = rpc_malloc,
2740 .buf_free = rpc_free,
2741 .prepare_request = xs_stream_prepare_request,
2742 .send_request = xs_local_send_request,
2743 .wait_for_reply_request = xprt_wait_for_reply_request_def,
2744 .close = xs_close,
2745 .destroy = xs_destroy,
2746 .print_stats = xs_local_print_stats,
2747 .enable_swap = xs_enable_swap,
2748 .disable_swap = xs_disable_swap,
2749};
2750
2751static const struct rpc_xprt_ops xs_udp_ops = {
2752 .set_buffer_size = xs_udp_set_buffer_size,
2753 .reserve_xprt = xprt_reserve_xprt_cong,
2754 .release_xprt = xprt_release_xprt_cong,
2755 .alloc_slot = xprt_alloc_slot,
2756 .free_slot = xprt_free_slot,
2757 .rpcbind = rpcb_getport_async,
2758 .set_port = xs_set_port,
2759 .connect = xs_connect,
2760 .buf_alloc = rpc_malloc,
2761 .buf_free = rpc_free,
2762 .send_request = xs_udp_send_request,
2763 .wait_for_reply_request = xprt_wait_for_reply_request_rtt,
2764 .timer = xs_udp_timer,
2765 .release_request = xprt_release_rqst_cong,
2766 .close = xs_close,
2767 .destroy = xs_destroy,
2768 .print_stats = xs_udp_print_stats,
2769 .enable_swap = xs_enable_swap,
2770 .disable_swap = xs_disable_swap,
2771 .inject_disconnect = xs_inject_disconnect,
2772};
2773
2774static const struct rpc_xprt_ops xs_tcp_ops = {
2775 .reserve_xprt = xprt_reserve_xprt,
2776 .release_xprt = xprt_release_xprt,
2777 .alloc_slot = xprt_alloc_slot,
2778 .free_slot = xprt_free_slot,
2779 .rpcbind = rpcb_getport_async,
2780 .set_port = xs_set_port,
2781 .connect = xs_connect,
2782 .buf_alloc = rpc_malloc,
2783 .buf_free = rpc_free,
2784 .prepare_request = xs_stream_prepare_request,
2785 .send_request = xs_tcp_send_request,
2786 .wait_for_reply_request = xprt_wait_for_reply_request_def,
2787 .close = xs_tcp_shutdown,
2788 .destroy = xs_destroy,
2789 .set_connect_timeout = xs_tcp_set_connect_timeout,
2790 .print_stats = xs_tcp_print_stats,
2791 .enable_swap = xs_enable_swap,
2792 .disable_swap = xs_disable_swap,
2793 .inject_disconnect = xs_inject_disconnect,
2794#ifdef CONFIG_SUNRPC_BACKCHANNEL
2795 .bc_setup = xprt_setup_bc,
2796 .bc_maxpayload = xs_tcp_bc_maxpayload,
2797 .bc_num_slots = xprt_bc_max_slots,
2798 .bc_free_rqst = xprt_free_bc_rqst,
2799 .bc_destroy = xprt_destroy_bc,
2800#endif
2801};
2802
2803/*
2804 * The rpc_xprt_ops for the server backchannel
2805 */
2806
2807static const struct rpc_xprt_ops bc_tcp_ops = {
2808 .reserve_xprt = xprt_reserve_xprt,
2809 .release_xprt = xprt_release_xprt,
2810 .alloc_slot = xprt_alloc_slot,
2811 .free_slot = xprt_free_slot,
2812 .buf_alloc = bc_malloc,
2813 .buf_free = bc_free,
2814 .send_request = bc_send_request,
2815 .wait_for_reply_request = xprt_wait_for_reply_request_def,
2816 .close = bc_close,
2817 .destroy = bc_destroy,
2818 .print_stats = xs_tcp_print_stats,
2819 .enable_swap = xs_enable_swap,
2820 .disable_swap = xs_disable_swap,
2821 .inject_disconnect = xs_inject_disconnect,
2822};
2823
2824static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2825{
2826 static const struct sockaddr_in sin = {
2827 .sin_family = AF_INET,
2828 .sin_addr.s_addr = htonl(INADDR_ANY),
2829 };
2830 static const struct sockaddr_in6 sin6 = {
2831 .sin6_family = AF_INET6,
2832 .sin6_addr = IN6ADDR_ANY_INIT,
2833 };
2834
2835 switch (family) {
2836 case AF_LOCAL:
2837 break;
2838 case AF_INET:
2839 memcpy(sap, &sin, sizeof(sin));
2840 break;
2841 case AF_INET6:
2842 memcpy(sap, &sin6, sizeof(sin6));
2843 break;
2844 default:
2845 dprintk("RPC: %s: Bad address family\n", __func__);
2846 return -EAFNOSUPPORT;
2847 }
2848 return 0;
2849}
2850
2851static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2852 unsigned int slot_table_size,
2853 unsigned int max_slot_table_size)
2854{
2855 struct rpc_xprt *xprt;
2856 struct sock_xprt *new;
2857
2858 if (args->addrlen > sizeof(xprt->addr)) {
2859 dprintk("RPC: xs_setup_xprt: address too large\n");
2860 return ERR_PTR(-EBADF);
2861 }
2862
2863 xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2864 max_slot_table_size);
2865 if (xprt == NULL) {
2866 dprintk("RPC: xs_setup_xprt: couldn't allocate "
2867 "rpc_xprt\n");
2868 return ERR_PTR(-ENOMEM);
2869 }
2870
2871 new = container_of(xprt, struct sock_xprt, xprt);
2872 mutex_init(&new->recv_mutex);
2873 memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2874 xprt->addrlen = args->addrlen;
2875 if (args->srcaddr)
2876 memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2877 else {
2878 int err;
2879 err = xs_init_anyaddr(args->dstaddr->sa_family,
2880 (struct sockaddr *)&new->srcaddr);
2881 if (err != 0) {
2882 xprt_free(xprt);
2883 return ERR_PTR(err);
2884 }
2885 }
2886
2887 return xprt;
2888}
2889
2890static const struct rpc_timeout xs_local_default_timeout = {
2891 .to_initval = 10 * HZ,
2892 .to_maxval = 10 * HZ,
2893 .to_retries = 2,
2894};
2895
2896/**
2897 * xs_setup_local - Set up transport to use an AF_LOCAL socket
2898 * @args: rpc transport creation arguments
2899 *
2900 * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2901 */
2902static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2903{
2904 struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2905 struct sock_xprt *transport;
2906 struct rpc_xprt *xprt;
2907 struct rpc_xprt *ret;
2908
2909 xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2910 xprt_max_tcp_slot_table_entries);
2911 if (IS_ERR(xprt))
2912 return xprt;
2913 transport = container_of(xprt, struct sock_xprt, xprt);
2914
2915 xprt->prot = 0;
2916 xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2917
2918 xprt->bind_timeout = XS_BIND_TO;
2919 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2920 xprt->idle_timeout = XS_IDLE_DISC_TO;
2921
2922 xprt->ops = &xs_local_ops;
2923 xprt->timeout = &xs_local_default_timeout;
2924
2925 INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2926 INIT_WORK(&transport->error_worker, xs_error_handle);
2927 INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket);
2928
2929 switch (sun->sun_family) {
2930 case AF_LOCAL:
2931 if (sun->sun_path[0] != '/') {
2932 dprintk("RPC: bad AF_LOCAL address: %s\n",
2933 sun->sun_path);
2934 ret = ERR_PTR(-EINVAL);
2935 goto out_err;
2936 }
2937 xprt_set_bound(xprt);
2938 xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
2939 ret = ERR_PTR(xs_local_setup_socket(transport));
2940 if (ret)
2941 goto out_err;
2942 break;
2943 default:
2944 ret = ERR_PTR(-EAFNOSUPPORT);
2945 goto out_err;
2946 }
2947
2948 dprintk("RPC: set up xprt to %s via AF_LOCAL\n",
2949 xprt->address_strings[RPC_DISPLAY_ADDR]);
2950
2951 if (try_module_get(THIS_MODULE))
2952 return xprt;
2953 ret = ERR_PTR(-EINVAL);
2954out_err:
2955 xs_xprt_free(xprt);
2956 return ret;
2957}
2958
2959static const struct rpc_timeout xs_udp_default_timeout = {
2960 .to_initval = 5 * HZ,
2961 .to_maxval = 30 * HZ,
2962 .to_increment = 5 * HZ,
2963 .to_retries = 5,
2964};
2965
2966/**
2967 * xs_setup_udp - Set up transport to use a UDP socket
2968 * @args: rpc transport creation arguments
2969 *
2970 */
2971static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2972{
2973 struct sockaddr *addr = args->dstaddr;
2974 struct rpc_xprt *xprt;
2975 struct sock_xprt *transport;
2976 struct rpc_xprt *ret;
2977
2978 xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2979 xprt_udp_slot_table_entries);
2980 if (IS_ERR(xprt))
2981 return xprt;
2982 transport = container_of(xprt, struct sock_xprt, xprt);
2983
2984 xprt->prot = IPPROTO_UDP;
2985 /* XXX: header size can vary due to auth type, IPv6, etc. */
2986 xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2987
2988 xprt->bind_timeout = XS_BIND_TO;
2989 xprt->reestablish_timeout = XS_UDP_REEST_TO;
2990 xprt->idle_timeout = XS_IDLE_DISC_TO;
2991
2992 xprt->ops = &xs_udp_ops;
2993
2994 xprt->timeout = &xs_udp_default_timeout;
2995
2996 INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
2997 INIT_WORK(&transport->error_worker, xs_error_handle);
2998 INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
2999
3000 switch (addr->sa_family) {
3001 case AF_INET:
3002 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3003 xprt_set_bound(xprt);
3004
3005 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
3006 break;
3007 case AF_INET6:
3008 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3009 xprt_set_bound(xprt);
3010
3011 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
3012 break;
3013 default:
3014 ret = ERR_PTR(-EAFNOSUPPORT);
3015 goto out_err;
3016 }
3017
3018 if (xprt_bound(xprt))
3019 dprintk("RPC: set up xprt to %s (port %s) via %s\n",
3020 xprt->address_strings[RPC_DISPLAY_ADDR],
3021 xprt->address_strings[RPC_DISPLAY_PORT],
3022 xprt->address_strings[RPC_DISPLAY_PROTO]);
3023 else
3024 dprintk("RPC: set up xprt to %s (autobind) via %s\n",
3025 xprt->address_strings[RPC_DISPLAY_ADDR],
3026 xprt->address_strings[RPC_DISPLAY_PROTO]);
3027
3028 if (try_module_get(THIS_MODULE))
3029 return xprt;
3030 ret = ERR_PTR(-EINVAL);
3031out_err:
3032 xs_xprt_free(xprt);
3033 return ret;
3034}
3035
3036static const struct rpc_timeout xs_tcp_default_timeout = {
3037 .to_initval = 60 * HZ,
3038 .to_maxval = 60 * HZ,
3039 .to_retries = 2,
3040};
3041
3042/**
3043 * xs_setup_tcp - Set up transport to use a TCP socket
3044 * @args: rpc transport creation arguments
3045 *
3046 */
3047static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
3048{
3049 struct sockaddr *addr = args->dstaddr;
3050 struct rpc_xprt *xprt;
3051 struct sock_xprt *transport;
3052 struct rpc_xprt *ret;
3053 unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
3054
3055 if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
3056 max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
3057
3058 xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3059 max_slot_table_size);
3060 if (IS_ERR(xprt))
3061 return xprt;
3062 transport = container_of(xprt, struct sock_xprt, xprt);
3063
3064 xprt->prot = IPPROTO_TCP;
3065 xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3066
3067 xprt->bind_timeout = XS_BIND_TO;
3068 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
3069 xprt->idle_timeout = XS_IDLE_DISC_TO;
3070
3071 xprt->ops = &xs_tcp_ops;
3072 xprt->timeout = &xs_tcp_default_timeout;
3073
3074 xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
3075 xprt->connect_timeout = xprt->timeout->to_initval *
3076 (xprt->timeout->to_retries + 1);
3077
3078 INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
3079 INIT_WORK(&transport->error_worker, xs_error_handle);
3080 INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
3081
3082 switch (addr->sa_family) {
3083 case AF_INET:
3084 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3085 xprt_set_bound(xprt);
3086
3087 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
3088 break;
3089 case AF_INET6:
3090 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3091 xprt_set_bound(xprt);
3092
3093 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
3094 break;
3095 default:
3096 ret = ERR_PTR(-EAFNOSUPPORT);
3097 goto out_err;
3098 }
3099
3100 if (xprt_bound(xprt))
3101 dprintk("RPC: set up xprt to %s (port %s) via %s\n",
3102 xprt->address_strings[RPC_DISPLAY_ADDR],
3103 xprt->address_strings[RPC_DISPLAY_PORT],
3104 xprt->address_strings[RPC_DISPLAY_PROTO]);
3105 else
3106 dprintk("RPC: set up xprt to %s (autobind) via %s\n",
3107 xprt->address_strings[RPC_DISPLAY_ADDR],
3108 xprt->address_strings[RPC_DISPLAY_PROTO]);
3109
3110 if (try_module_get(THIS_MODULE))
3111 return xprt;
3112 ret = ERR_PTR(-EINVAL);
3113out_err:
3114 xs_xprt_free(xprt);
3115 return ret;
3116}
3117
3118/**
3119 * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
3120 * @args: rpc transport creation arguments
3121 *
3122 */
3123static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
3124{
3125 struct sockaddr *addr = args->dstaddr;
3126 struct rpc_xprt *xprt;
3127 struct sock_xprt *transport;
3128 struct svc_sock *bc_sock;
3129 struct rpc_xprt *ret;
3130
3131 xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3132 xprt_tcp_slot_table_entries);
3133 if (IS_ERR(xprt))
3134 return xprt;
3135 transport = container_of(xprt, struct sock_xprt, xprt);
3136
3137 xprt->prot = IPPROTO_TCP;
3138 xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3139 xprt->timeout = &xs_tcp_default_timeout;
3140
3141 /* backchannel */
3142 xprt_set_bound(xprt);
3143 xprt->bind_timeout = 0;
3144 xprt->reestablish_timeout = 0;
3145 xprt->idle_timeout = 0;
3146
3147 xprt->ops = &bc_tcp_ops;
3148
3149 switch (addr->sa_family) {
3150 case AF_INET:
3151 xs_format_peer_addresses(xprt, "tcp",
3152 RPCBIND_NETID_TCP);
3153 break;
3154 case AF_INET6:
3155 xs_format_peer_addresses(xprt, "tcp",
3156 RPCBIND_NETID_TCP6);
3157 break;
3158 default:
3159 ret = ERR_PTR(-EAFNOSUPPORT);
3160 goto out_err;
3161 }
3162
3163 dprintk("RPC: set up xprt to %s (port %s) via %s\n",
3164 xprt->address_strings[RPC_DISPLAY_ADDR],
3165 xprt->address_strings[RPC_DISPLAY_PORT],
3166 xprt->address_strings[RPC_DISPLAY_PROTO]);
3167
3168 /*
3169 * Once we've associated a backchannel xprt with a connection,
3170 * we want to keep it around as long as the connection lasts,
3171 * in case we need to start using it for a backchannel again;
3172 * this reference won't be dropped until bc_xprt is destroyed.
3173 */
3174 xprt_get(xprt);
3175 args->bc_xprt->xpt_bc_xprt = xprt;
3176 xprt->bc_xprt = args->bc_xprt;
3177 bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3178 transport->sock = bc_sock->sk_sock;
3179 transport->inet = bc_sock->sk_sk;
3180
3181 /*
3182 * Since we don't want connections for the backchannel, we set
3183 * the xprt status to connected
3184 */
3185 xprt_set_connected(xprt);
3186
3187 if (try_module_get(THIS_MODULE))
3188 return xprt;
3189
3190 args->bc_xprt->xpt_bc_xprt = NULL;
3191 args->bc_xprt->xpt_bc_xps = NULL;
3192 xprt_put(xprt);
3193 ret = ERR_PTR(-EINVAL);
3194out_err:
3195 xs_xprt_free(xprt);
3196 return ret;
3197}
3198
3199static struct xprt_class xs_local_transport = {
3200 .list = LIST_HEAD_INIT(xs_local_transport.list),
3201 .name = "named UNIX socket",
3202 .owner = THIS_MODULE,
3203 .ident = XPRT_TRANSPORT_LOCAL,
3204 .setup = xs_setup_local,
3205};
3206
3207static struct xprt_class xs_udp_transport = {
3208 .list = LIST_HEAD_INIT(xs_udp_transport.list),
3209 .name = "udp",
3210 .owner = THIS_MODULE,
3211 .ident = XPRT_TRANSPORT_UDP,
3212 .setup = xs_setup_udp,
3213};
3214
3215static struct xprt_class xs_tcp_transport = {
3216 .list = LIST_HEAD_INIT(xs_tcp_transport.list),
3217 .name = "tcp",
3218 .owner = THIS_MODULE,
3219 .ident = XPRT_TRANSPORT_TCP,
3220 .setup = xs_setup_tcp,
3221};
3222
3223static struct xprt_class xs_bc_tcp_transport = {
3224 .list = LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3225 .name = "tcp NFSv4.1 backchannel",
3226 .owner = THIS_MODULE,
3227 .ident = XPRT_TRANSPORT_BC_TCP,
3228 .setup = xs_setup_bc_tcp,
3229};
3230
3231/**
3232 * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3233 *
3234 */
3235int init_socket_xprt(void)
3236{
3237 if (!sunrpc_table_header)
3238 sunrpc_table_header = register_sysctl_table(sunrpc_table);
3239
3240 xprt_register_transport(&xs_local_transport);
3241 xprt_register_transport(&xs_udp_transport);
3242 xprt_register_transport(&xs_tcp_transport);
3243 xprt_register_transport(&xs_bc_tcp_transport);
3244
3245 return 0;
3246}
3247
3248/**
3249 * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3250 *
3251 */
3252void cleanup_socket_xprt(void)
3253{
3254 if (sunrpc_table_header) {
3255 unregister_sysctl_table(sunrpc_table_header);
3256 sunrpc_table_header = NULL;
3257 }
3258
3259 xprt_unregister_transport(&xs_local_transport);
3260 xprt_unregister_transport(&xs_udp_transport);
3261 xprt_unregister_transport(&xs_tcp_transport);
3262 xprt_unregister_transport(&xs_bc_tcp_transport);
3263}
3264
3265static int param_set_uint_minmax(const char *val,
3266 const struct kernel_param *kp,
3267 unsigned int min, unsigned int max)
3268{
3269 unsigned int num;
3270 int ret;
3271
3272 if (!val)
3273 return -EINVAL;
3274 ret = kstrtouint(val, 0, &num);
3275 if (ret)
3276 return ret;
3277 if (num < min || num > max)
3278 return -EINVAL;
3279 *((unsigned int *)kp->arg) = num;
3280 return 0;
3281}
3282
3283static int param_set_portnr(const char *val, const struct kernel_param *kp)
3284{
3285 return param_set_uint_minmax(val, kp,
3286 RPC_MIN_RESVPORT,
3287 RPC_MAX_RESVPORT);
3288}
3289
3290static const struct kernel_param_ops param_ops_portnr = {
3291 .set = param_set_portnr,
3292 .get = param_get_uint,
3293};
3294
3295#define param_check_portnr(name, p) \
3296 __param_check(name, p, unsigned int);
3297
3298module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3299module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3300
3301static int param_set_slot_table_size(const char *val,
3302 const struct kernel_param *kp)
3303{
3304 return param_set_uint_minmax(val, kp,
3305 RPC_MIN_SLOT_TABLE,
3306 RPC_MAX_SLOT_TABLE);
3307}
3308
3309static const struct kernel_param_ops param_ops_slot_table_size = {
3310 .set = param_set_slot_table_size,
3311 .get = param_get_uint,
3312};
3313
3314#define param_check_slot_table_size(name, p) \
3315 __param_check(name, p, unsigned int);
3316
3317static int param_set_max_slot_table_size(const char *val,
3318 const struct kernel_param *kp)
3319{
3320 return param_set_uint_minmax(val, kp,
3321 RPC_MIN_SLOT_TABLE,
3322 RPC_MAX_SLOT_TABLE_LIMIT);
3323}
3324
3325static const struct kernel_param_ops param_ops_max_slot_table_size = {
3326 .set = param_set_max_slot_table_size,
3327 .get = param_get_uint,
3328};
3329
3330#define param_check_max_slot_table_size(name, p) \
3331 __param_check(name, p, unsigned int);
3332
3333module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3334 slot_table_size, 0644);
3335module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3336 max_slot_table_size, 0644);
3337module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3338 slot_table_size, 0644);