use less confusing names for iov_iter direction initializers
[linux-block.git] / net / sunrpc / xprtsock.c
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
60 static void xs_close(struct rpc_xprt *xprt);
61 static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock);
62 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
63                 struct socket *sock);
64
65 /*
66  * xprtsock tunables
67  */
68 static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
69 static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
70 static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
71
72 static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
73 static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
74
75 #define XS_TCP_LINGER_TO        (15U * HZ)
76 static 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
87 static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
88 static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
89 static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
90 static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
91 static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
92
93 static struct ctl_table_header *sunrpc_table_header;
94
95 static struct xprt_class xs_local_transport;
96 static struct xprt_class xs_udp_transport;
97 static struct xprt_class xs_tcp_transport;
98 static 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  */
104 static 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
160 static 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
204 static 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
222 static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
223 {
224         /* NOP */
225 }
226 #endif
227
228 static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
229 {
230         return (struct rpc_xprt *) sk->sk_user_data;
231 }
232
233 static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
234 {
235         return (struct sockaddr *) &xprt->addr;
236 }
237
238 static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
239 {
240         return (struct sockaddr_un *) &xprt->addr;
241 }
242
243 static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
244 {
245         return (struct sockaddr_in *) &xprt->addr;
246 }
247
248 static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
249 {
250         return (struct sockaddr_in6 *) &xprt->addr;
251 }
252
253 static 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
289 static 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
301 static 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
311 static 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
319 static 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
333 static size_t
334 xs_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
353 static ssize_t
354 xs_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
363 static ssize_t
364 xs_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
371 static ssize_t
372 xs_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
380 static ssize_t
381 xs_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
389 static void
390 xs_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
402 static inline void
403 xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
404 {
405 }
406 #endif
407
408 static ssize_t
409 xs_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;
467 out:
468         *read = offset - seek_init;
469         return ret;
470 sock_err:
471         offset += seek;
472         goto out;
473 }
474
475 static void
476 xs_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
487 static bool
488 xs_read_stream_request_done(struct sock_xprt *transport)
489 {
490         return transport->recv.fraghdr & cpu_to_be32(RPC_LAST_STREAM_FRAGMENT);
491 }
492
493 static void
494 xs_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
501 static ssize_t
502 xs_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
540 static size_t
541 xs_read_stream_headersize(bool isfrag)
542 {
543         if (isfrag)
544                 return sizeof(__be32);
545         return 3 * sizeof(__be32);
546 }
547
548 static ssize_t
549 xs_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)
560 static ssize_t
561 xs_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 */
589 static ssize_t
590 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
591 {
592         return -ESHUTDOWN;
593 }
594 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
595
596 static ssize_t
597 xs_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);
621 out:
622         spin_unlock(&xprt->queue_lock);
623         return ret;
624 }
625
626 static ssize_t
627 xs_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;
685 out_err:
686         return ret != 0 ? ret : -ESHUTDOWN;
687 }
688
689 static __poll_t xs_poll_socket(struct sock_xprt *transport)
690 {
691         return transport->sock->ops->poll(transport->file, transport->sock,
692                         NULL);
693 }
694
695 static 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
702 static 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
712 static 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);
731 out:
732         mutex_unlock(&transport->recv_mutex);
733         trace_xs_stream_read_data(&transport->xprt, ret, read);
734 }
735
736 static 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
746 static void
747 xs_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
755 static void
756 xs_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  */
770 static 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
795 static 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
809 static 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
825 static 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  */
834 static bool
835 xs_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  */
843 static rpc_fraghdr
844 xs_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  */
862 static 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  */
933 static 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
980 process_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  */
1019 static 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
1108 static 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
1116 static 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
1124 static 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
1135 static 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
1141 static 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  */
1158 static 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
1179 static 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  */
1236 static 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
1246 static 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
1253 static 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  */
1264 static 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  */
1285 static 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);
1333 out_unpin:
1334         xprt_unpin_rqst(rovr);
1335  out_unlock:
1336         spin_unlock(&xprt->queue_lock);
1337 }
1338
1339 static 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);
1358 out:
1359         mutex_unlock(&transport->recv_mutex);
1360 }
1361
1362 static 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  */
1377 static 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  */
1403 static void xs_tcp_force_close(struct rpc_xprt *xprt)
1404 {
1405         xprt_force_disconnect(xprt);
1406 }
1407
1408 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1409 static 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  */
1420 static 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  */
1440 static 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
1509 static 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  */
1537 static 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  */
1554 static 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
1561 static 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  */
1585 static 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  */
1606 static 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
1613 static 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 = prandom_u32_max(range);
1623         return rand + min;
1624 }
1625
1626 static 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         }
1640 out:
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  */
1650 static 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
1658 static 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
1664 static 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
1673 static 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
1684 static 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
1703 static 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 }
1713 static 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  */
1768 static void xs_local_rpcbind(struct rpc_task *task)
1769 {
1770         xprt_set_bound(task->tk_xprt);
1771 }
1772
1773 static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1774 {
1775 }
1776
1777 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1778 static struct lock_class_key xs_key[3];
1779 static struct lock_class_key xs_slock_key[3];
1780
1781 static 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
1789 static 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
1797 static 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
1805 static 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
1823 static inline void xs_reclassify_socket(int family, struct socket *sock)
1824 {
1825 }
1826 #endif
1827
1828 static void xs_dummy_setup_socket(struct work_struct *work)
1829 {
1830 }
1831
1832 static 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;
1863 out:
1864         return ERR_PTR(err);
1865 }
1866
1867 static 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
1886                 xprt_clear_connected(xprt);
1887
1888                 /* Reset to new socket */
1889                 transport->sock = sock;
1890                 transport->inet = sk;
1891
1892                 release_sock(sk);
1893         }
1894
1895         xs_stream_start_connect(transport);
1896
1897         return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1898 }
1899
1900 /**
1901  * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1902  * @transport: socket transport to connect
1903  */
1904 static int xs_local_setup_socket(struct sock_xprt *transport)
1905 {
1906         struct rpc_xprt *xprt = &transport->xprt;
1907         struct file *filp;
1908         struct socket *sock;
1909         int status;
1910
1911         status = __sock_create(xprt->xprt_net, AF_LOCAL,
1912                                         SOCK_STREAM, 0, &sock, 1);
1913         if (status < 0) {
1914                 dprintk("RPC:       can't create AF_LOCAL "
1915                         "transport socket (%d).\n", -status);
1916                 goto out;
1917         }
1918         xs_reclassify_socket(AF_LOCAL, sock);
1919
1920         filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1921         if (IS_ERR(filp)) {
1922                 status = PTR_ERR(filp);
1923                 goto out;
1924         }
1925         transport->file = filp;
1926
1927         dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
1928                         xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1929
1930         status = xs_local_finish_connecting(xprt, sock);
1931         trace_rpc_socket_connect(xprt, sock, status);
1932         switch (status) {
1933         case 0:
1934                 dprintk("RPC:       xprt %p connected to %s\n",
1935                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1936                 xprt->stat.connect_count++;
1937                 xprt->stat.connect_time += (long)jiffies -
1938                                            xprt->stat.connect_start;
1939                 xprt_set_connected(xprt);
1940                 break;
1941         case -ENOBUFS:
1942                 break;
1943         case -ENOENT:
1944                 dprintk("RPC:       xprt %p: socket %s does not exist\n",
1945                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1946                 break;
1947         case -ECONNREFUSED:
1948                 dprintk("RPC:       xprt %p: connection refused for %s\n",
1949                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1950                 break;
1951         default:
1952                 printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
1953                                 __func__, -status,
1954                                 xprt->address_strings[RPC_DISPLAY_ADDR]);
1955         }
1956
1957 out:
1958         xprt_clear_connecting(xprt);
1959         xprt_wake_pending_tasks(xprt, status);
1960         return status;
1961 }
1962
1963 static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
1964 {
1965         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1966         int ret;
1967
1968         if (transport->file)
1969                 goto force_disconnect;
1970
1971         if (RPC_IS_ASYNC(task)) {
1972                 /*
1973                  * We want the AF_LOCAL connect to be resolved in the
1974                  * filesystem namespace of the process making the rpc
1975                  * call.  Thus we connect synchronously.
1976                  *
1977                  * If we want to support asynchronous AF_LOCAL calls,
1978                  * we'll need to figure out how to pass a namespace to
1979                  * connect.
1980                  */
1981                 rpc_task_set_rpc_status(task, -ENOTCONN);
1982                 goto out_wake;
1983         }
1984         ret = xs_local_setup_socket(transport);
1985         if (ret && !RPC_IS_SOFTCONN(task))
1986                 msleep_interruptible(15000);
1987         return;
1988 force_disconnect:
1989         xprt_force_disconnect(xprt);
1990 out_wake:
1991         xprt_clear_connecting(xprt);
1992         xprt_wake_pending_tasks(xprt, -ENOTCONN);
1993 }
1994
1995 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
1996 /*
1997  * Note that this should be called with XPRT_LOCKED held, or recv_mutex
1998  * held, or when we otherwise know that we have exclusive access to the
1999  * socket, to guard against races with xs_reset_transport.
2000  */
2001 static void xs_set_memalloc(struct rpc_xprt *xprt)
2002 {
2003         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
2004                         xprt);
2005
2006         /*
2007          * If there's no sock, then we have nothing to set. The
2008          * reconnecting process will get it for us.
2009          */
2010         if (!transport->inet)
2011                 return;
2012         if (atomic_read(&xprt->swapper))
2013                 sk_set_memalloc(transport->inet);
2014 }
2015
2016 /**
2017  * xs_enable_swap - Tag this transport as being used for swap.
2018  * @xprt: transport to tag
2019  *
2020  * Take a reference to this transport on behalf of the rpc_clnt, and
2021  * optionally mark it for swapping if it wasn't already.
2022  */
2023 static int
2024 xs_enable_swap(struct rpc_xprt *xprt)
2025 {
2026         struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2027
2028         mutex_lock(&xs->recv_mutex);
2029         if (atomic_inc_return(&xprt->swapper) == 1 &&
2030             xs->inet)
2031                 sk_set_memalloc(xs->inet);
2032         mutex_unlock(&xs->recv_mutex);
2033         return 0;
2034 }
2035
2036 /**
2037  * xs_disable_swap - Untag this transport as being used for swap.
2038  * @xprt: transport to tag
2039  *
2040  * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
2041  * swapper refcount goes to 0, untag the socket as a memalloc socket.
2042  */
2043 static void
2044 xs_disable_swap(struct rpc_xprt *xprt)
2045 {
2046         struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2047
2048         mutex_lock(&xs->recv_mutex);
2049         if (atomic_dec_and_test(&xprt->swapper) &&
2050             xs->inet)
2051                 sk_clear_memalloc(xs->inet);
2052         mutex_unlock(&xs->recv_mutex);
2053 }
2054 #else
2055 static void xs_set_memalloc(struct rpc_xprt *xprt)
2056 {
2057 }
2058
2059 static int
2060 xs_enable_swap(struct rpc_xprt *xprt)
2061 {
2062         return -EINVAL;
2063 }
2064
2065 static void
2066 xs_disable_swap(struct rpc_xprt *xprt)
2067 {
2068 }
2069 #endif
2070
2071 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2072 {
2073         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2074
2075         if (!transport->inet) {
2076                 struct sock *sk = sock->sk;
2077
2078                 lock_sock(sk);
2079
2080                 xs_save_old_callbacks(transport, sk);
2081
2082                 sk->sk_user_data = xprt;
2083                 sk->sk_data_ready = xs_data_ready;
2084                 sk->sk_write_space = xs_udp_write_space;
2085
2086                 xprt_set_connected(xprt);
2087
2088                 /* Reset to new socket */
2089                 transport->sock = sock;
2090                 transport->inet = sk;
2091
2092                 xs_set_memalloc(xprt);
2093
2094                 release_sock(sk);
2095         }
2096         xs_udp_do_set_buffer_size(xprt);
2097
2098         xprt->stat.connect_start = jiffies;
2099 }
2100
2101 static void xs_udp_setup_socket(struct work_struct *work)
2102 {
2103         struct sock_xprt *transport =
2104                 container_of(work, struct sock_xprt, connect_worker.work);
2105         struct rpc_xprt *xprt = &transport->xprt;
2106         struct socket *sock;
2107         int status = -EIO;
2108         unsigned int pflags = current->flags;
2109
2110         if (atomic_read(&xprt->swapper))
2111                 current->flags |= PF_MEMALLOC;
2112         sock = xs_create_sock(xprt, transport,
2113                         xs_addr(xprt)->sa_family, SOCK_DGRAM,
2114                         IPPROTO_UDP, false);
2115         if (IS_ERR(sock))
2116                 goto out;
2117
2118         dprintk("RPC:       worker connecting xprt %p via %s to "
2119                                 "%s (port %s)\n", xprt,
2120                         xprt->address_strings[RPC_DISPLAY_PROTO],
2121                         xprt->address_strings[RPC_DISPLAY_ADDR],
2122                         xprt->address_strings[RPC_DISPLAY_PORT]);
2123
2124         xs_udp_finish_connecting(xprt, sock);
2125         trace_rpc_socket_connect(xprt, sock, 0);
2126         status = 0;
2127 out:
2128         xprt_clear_connecting(xprt);
2129         xprt_unlock_connect(xprt, transport);
2130         xprt_wake_pending_tasks(xprt, status);
2131         current_restore_flags(pflags, PF_MEMALLOC);
2132 }
2133
2134 /**
2135  * xs_tcp_shutdown - gracefully shut down a TCP socket
2136  * @xprt: transport
2137  *
2138  * Initiates a graceful shutdown of the TCP socket by calling the
2139  * equivalent of shutdown(SHUT_RDWR);
2140  */
2141 static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2142 {
2143         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2144         struct socket *sock = transport->sock;
2145         int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
2146
2147         if (sock == NULL)
2148                 return;
2149         if (!xprt->reuseport) {
2150                 xs_close(xprt);
2151                 return;
2152         }
2153         switch (skst) {
2154         case TCP_FIN_WAIT1:
2155         case TCP_FIN_WAIT2:
2156                 break;
2157         case TCP_ESTABLISHED:
2158         case TCP_CLOSE_WAIT:
2159                 kernel_sock_shutdown(sock, SHUT_RDWR);
2160                 trace_rpc_socket_shutdown(xprt, sock);
2161                 break;
2162         default:
2163                 xs_reset_transport(transport);
2164         }
2165 }
2166
2167 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
2168                 struct socket *sock)
2169 {
2170         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2171         unsigned int keepidle;
2172         unsigned int keepcnt;
2173         unsigned int timeo;
2174
2175         spin_lock(&xprt->transport_lock);
2176         keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
2177         keepcnt = xprt->timeout->to_retries + 1;
2178         timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2179                 (xprt->timeout->to_retries + 1);
2180         clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2181         spin_unlock(&xprt->transport_lock);
2182
2183         /* TCP Keepalive options */
2184         sock_set_keepalive(sock->sk);
2185         tcp_sock_set_keepidle(sock->sk, keepidle);
2186         tcp_sock_set_keepintvl(sock->sk, keepidle);
2187         tcp_sock_set_keepcnt(sock->sk, keepcnt);
2188
2189         /* TCP user timeout (see RFC5482) */
2190         tcp_sock_set_user_timeout(sock->sk, timeo);
2191 }
2192
2193 static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
2194                 unsigned long connect_timeout,
2195                 unsigned long reconnect_timeout)
2196 {
2197         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2198         struct rpc_timeout to;
2199         unsigned long initval;
2200
2201         spin_lock(&xprt->transport_lock);
2202         if (reconnect_timeout < xprt->max_reconnect_timeout)
2203                 xprt->max_reconnect_timeout = reconnect_timeout;
2204         if (connect_timeout < xprt->connect_timeout) {
2205                 memcpy(&to, xprt->timeout, sizeof(to));
2206                 initval = DIV_ROUND_UP(connect_timeout, to.to_retries + 1);
2207                 /* Arbitrary lower limit */
2208                 if (initval <  XS_TCP_INIT_REEST_TO << 1)
2209                         initval = XS_TCP_INIT_REEST_TO << 1;
2210                 to.to_initval = initval;
2211                 to.to_maxval = initval;
2212                 memcpy(&transport->tcp_timeout, &to,
2213                                 sizeof(transport->tcp_timeout));
2214                 xprt->timeout = &transport->tcp_timeout;
2215                 xprt->connect_timeout = connect_timeout;
2216         }
2217         set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2218         spin_unlock(&xprt->transport_lock);
2219 }
2220
2221 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2222 {
2223         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2224
2225         if (!transport->inet) {
2226                 struct sock *sk = sock->sk;
2227
2228                 /* Avoid temporary address, they are bad for long-lived
2229                  * connections such as NFS mounts.
2230                  * RFC4941, section 3.6 suggests that:
2231                  *    Individual applications, which have specific
2232                  *    knowledge about the normal duration of connections,
2233                  *    MAY override this as appropriate.
2234                  */
2235                 if (xs_addr(xprt)->sa_family == PF_INET6) {
2236                         ip6_sock_set_addr_preferences(sk,
2237                                 IPV6_PREFER_SRC_PUBLIC);
2238                 }
2239
2240                 xs_tcp_set_socket_timeouts(xprt, sock);
2241                 tcp_sock_set_nodelay(sk);
2242
2243                 lock_sock(sk);
2244
2245                 xs_save_old_callbacks(transport, sk);
2246
2247                 sk->sk_user_data = xprt;
2248                 sk->sk_data_ready = xs_data_ready;
2249                 sk->sk_state_change = xs_tcp_state_change;
2250                 sk->sk_write_space = xs_tcp_write_space;
2251                 sk->sk_error_report = xs_error_report;
2252
2253                 /* socket options */
2254                 sock_reset_flag(sk, SOCK_LINGER);
2255
2256                 xprt_clear_connected(xprt);
2257
2258                 /* Reset to new socket */
2259                 transport->sock = sock;
2260                 transport->inet = sk;
2261
2262                 release_sock(sk);
2263         }
2264
2265         if (!xprt_bound(xprt))
2266                 return -ENOTCONN;
2267
2268         xs_set_memalloc(xprt);
2269
2270         xs_stream_start_connect(transport);
2271
2272         /* Tell the socket layer to start connecting... */
2273         set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2274         return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2275 }
2276
2277 /**
2278  * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2279  * @work: queued work item
2280  *
2281  * Invoked by a work queue tasklet.
2282  */
2283 static void xs_tcp_setup_socket(struct work_struct *work)
2284 {
2285         struct sock_xprt *transport =
2286                 container_of(work, struct sock_xprt, connect_worker.work);
2287         struct socket *sock = transport->sock;
2288         struct rpc_xprt *xprt = &transport->xprt;
2289         int status;
2290         unsigned int pflags = current->flags;
2291
2292         if (atomic_read(&xprt->swapper))
2293                 current->flags |= PF_MEMALLOC;
2294
2295         if (xprt_connected(xprt))
2296                 goto out;
2297         if (test_and_clear_bit(XPRT_SOCK_CONNECT_SENT,
2298                                &transport->sock_state) ||
2299             !sock) {
2300                 xs_reset_transport(transport);
2301                 sock = xs_create_sock(xprt, transport, xs_addr(xprt)->sa_family,
2302                                       SOCK_STREAM, IPPROTO_TCP, true);
2303                 if (IS_ERR(sock)) {
2304                         xprt_wake_pending_tasks(xprt, PTR_ERR(sock));
2305                         goto out;
2306                 }
2307         }
2308
2309         dprintk("RPC:       worker connecting xprt %p via %s to "
2310                                 "%s (port %s)\n", xprt,
2311                         xprt->address_strings[RPC_DISPLAY_PROTO],
2312                         xprt->address_strings[RPC_DISPLAY_ADDR],
2313                         xprt->address_strings[RPC_DISPLAY_PORT]);
2314
2315         status = xs_tcp_finish_connecting(xprt, sock);
2316         trace_rpc_socket_connect(xprt, sock, status);
2317         dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2318                         xprt, -status, xprt_connected(xprt),
2319                         sock->sk->sk_state);
2320         switch (status) {
2321         case 0:
2322         case -EINPROGRESS:
2323                 /* SYN_SENT! */
2324                 set_bit(XPRT_SOCK_CONNECT_SENT, &transport->sock_state);
2325                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2326                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2327                 fallthrough;
2328         case -EALREADY:
2329                 goto out_unlock;
2330         case -EADDRNOTAVAIL:
2331                 /* Source port number is unavailable. Try a new one! */
2332                 transport->srcport = 0;
2333                 status = -EAGAIN;
2334                 break;
2335         case -EINVAL:
2336                 /* Happens, for instance, if the user specified a link
2337                  * local IPv6 address without a scope-id.
2338                  */
2339         case -ECONNREFUSED:
2340         case -ECONNRESET:
2341         case -ENETDOWN:
2342         case -ENETUNREACH:
2343         case -EHOSTUNREACH:
2344         case -EADDRINUSE:
2345         case -ENOBUFS:
2346                 break;
2347         default:
2348                 printk("%s: connect returned unhandled error %d\n",
2349                         __func__, status);
2350                 status = -EAGAIN;
2351         }
2352
2353         /* xs_tcp_force_close() wakes tasks with a fixed error code.
2354          * We need to wake them first to ensure the correct error code.
2355          */
2356         xprt_wake_pending_tasks(xprt, status);
2357         xs_tcp_force_close(xprt);
2358 out:
2359         xprt_clear_connecting(xprt);
2360 out_unlock:
2361         xprt_unlock_connect(xprt, transport);
2362         current_restore_flags(pflags, PF_MEMALLOC);
2363 }
2364
2365 /**
2366  * xs_connect - connect a socket to a remote endpoint
2367  * @xprt: pointer to transport structure
2368  * @task: address of RPC task that manages state of connect request
2369  *
2370  * TCP: If the remote end dropped the connection, delay reconnecting.
2371  *
2372  * UDP socket connects are synchronous, but we use a work queue anyway
2373  * to guarantee that even unprivileged user processes can set up a
2374  * socket on a privileged port.
2375  *
2376  * If a UDP socket connect fails, the delay behavior here prevents
2377  * retry floods (hard mounts).
2378  */
2379 static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2380 {
2381         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2382         unsigned long delay = 0;
2383
2384         WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2385
2386         if (transport->sock != NULL) {
2387                 dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2388                         "seconds\n", xprt, xprt->reestablish_timeout / HZ);
2389
2390                 delay = xprt_reconnect_delay(xprt);
2391                 xprt_reconnect_backoff(xprt, XS_TCP_INIT_REEST_TO);
2392
2393         } else
2394                 dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2395
2396         queue_delayed_work(xprtiod_workqueue,
2397                         &transport->connect_worker,
2398                         delay);
2399 }
2400
2401 static void xs_wake_disconnect(struct sock_xprt *transport)
2402 {
2403         if (test_and_clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state))
2404                 xs_tcp_force_close(&transport->xprt);
2405 }
2406
2407 static void xs_wake_write(struct sock_xprt *transport)
2408 {
2409         if (test_and_clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state))
2410                 xprt_write_space(&transport->xprt);
2411 }
2412
2413 static void xs_wake_error(struct sock_xprt *transport)
2414 {
2415         int sockerr;
2416
2417         if (!test_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2418                 return;
2419         mutex_lock(&transport->recv_mutex);
2420         if (transport->sock == NULL)
2421                 goto out;
2422         if (!test_and_clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2423                 goto out;
2424         sockerr = xchg(&transport->xprt_err, 0);
2425         if (sockerr < 0)
2426                 xprt_wake_pending_tasks(&transport->xprt, sockerr);
2427 out:
2428         mutex_unlock(&transport->recv_mutex);
2429 }
2430
2431 static void xs_wake_pending(struct sock_xprt *transport)
2432 {
2433         if (test_and_clear_bit(XPRT_SOCK_WAKE_PENDING, &transport->sock_state))
2434                 xprt_wake_pending_tasks(&transport->xprt, -EAGAIN);
2435 }
2436
2437 static void xs_error_handle(struct work_struct *work)
2438 {
2439         struct sock_xprt *transport = container_of(work,
2440                         struct sock_xprt, error_worker);
2441
2442         xs_wake_disconnect(transport);
2443         xs_wake_write(transport);
2444         xs_wake_error(transport);
2445         xs_wake_pending(transport);
2446 }
2447
2448 /**
2449  * xs_local_print_stats - display AF_LOCAL socket-specific stats
2450  * @xprt: rpc_xprt struct containing statistics
2451  * @seq: output file
2452  *
2453  */
2454 static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2455 {
2456         long idle_time = 0;
2457
2458         if (xprt_connected(xprt))
2459                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2460
2461         seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2462                         "%llu %llu %lu %llu %llu\n",
2463                         xprt->stat.bind_count,
2464                         xprt->stat.connect_count,
2465                         xprt->stat.connect_time / HZ,
2466                         idle_time,
2467                         xprt->stat.sends,
2468                         xprt->stat.recvs,
2469                         xprt->stat.bad_xids,
2470                         xprt->stat.req_u,
2471                         xprt->stat.bklog_u,
2472                         xprt->stat.max_slots,
2473                         xprt->stat.sending_u,
2474                         xprt->stat.pending_u);
2475 }
2476
2477 /**
2478  * xs_udp_print_stats - display UDP socket-specific stats
2479  * @xprt: rpc_xprt struct containing statistics
2480  * @seq: output file
2481  *
2482  */
2483 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2484 {
2485         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2486
2487         seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2488                         "%lu %llu %llu\n",
2489                         transport->srcport,
2490                         xprt->stat.bind_count,
2491                         xprt->stat.sends,
2492                         xprt->stat.recvs,
2493                         xprt->stat.bad_xids,
2494                         xprt->stat.req_u,
2495                         xprt->stat.bklog_u,
2496                         xprt->stat.max_slots,
2497                         xprt->stat.sending_u,
2498                         xprt->stat.pending_u);
2499 }
2500
2501 /**
2502  * xs_tcp_print_stats - display TCP socket-specific stats
2503  * @xprt: rpc_xprt struct containing statistics
2504  * @seq: output file
2505  *
2506  */
2507 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2508 {
2509         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2510         long idle_time = 0;
2511
2512         if (xprt_connected(xprt))
2513                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2514
2515         seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2516                         "%llu %llu %lu %llu %llu\n",
2517                         transport->srcport,
2518                         xprt->stat.bind_count,
2519                         xprt->stat.connect_count,
2520                         xprt->stat.connect_time / HZ,
2521                         idle_time,
2522                         xprt->stat.sends,
2523                         xprt->stat.recvs,
2524                         xprt->stat.bad_xids,
2525                         xprt->stat.req_u,
2526                         xprt->stat.bklog_u,
2527                         xprt->stat.max_slots,
2528                         xprt->stat.sending_u,
2529                         xprt->stat.pending_u);
2530 }
2531
2532 /*
2533  * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2534  * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2535  * to use the server side send routines.
2536  */
2537 static int bc_malloc(struct rpc_task *task)
2538 {
2539         struct rpc_rqst *rqst = task->tk_rqstp;
2540         size_t size = rqst->rq_callsize;
2541         struct page *page;
2542         struct rpc_buffer *buf;
2543
2544         if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2545                 WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2546                           size);
2547                 return -EINVAL;
2548         }
2549
2550         page = alloc_page(GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
2551         if (!page)
2552                 return -ENOMEM;
2553
2554         buf = page_address(page);
2555         buf->len = PAGE_SIZE;
2556
2557         rqst->rq_buffer = buf->data;
2558         rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2559         return 0;
2560 }
2561
2562 /*
2563  * Free the space allocated in the bc_alloc routine
2564  */
2565 static void bc_free(struct rpc_task *task)
2566 {
2567         void *buffer = task->tk_rqstp->rq_buffer;
2568         struct rpc_buffer *buf;
2569
2570         buf = container_of(buffer, struct rpc_buffer, data);
2571         free_page((unsigned long)buf);
2572 }
2573
2574 static int bc_sendto(struct rpc_rqst *req)
2575 {
2576         struct xdr_buf *xdr = &req->rq_snd_buf;
2577         struct sock_xprt *transport =
2578                         container_of(req->rq_xprt, struct sock_xprt, xprt);
2579         struct msghdr msg = {
2580                 .msg_flags      = 0,
2581         };
2582         rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT |
2583                                          (u32)xdr->len);
2584         unsigned int sent = 0;
2585         int err;
2586
2587         req->rq_xtime = ktime_get();
2588         err = xdr_alloc_bvec(xdr, rpc_task_gfp_mask());
2589         if (err < 0)
2590                 return err;
2591         err = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, marker, &sent);
2592         xdr_free_bvec(xdr);
2593         if (err < 0 || sent != (xdr->len + sizeof(marker)))
2594                 return -EAGAIN;
2595         return sent;
2596 }
2597
2598 /**
2599  * bc_send_request - Send a backchannel Call on a TCP socket
2600  * @req: rpc_rqst containing Call message to be sent
2601  *
2602  * xpt_mutex ensures @rqstp's whole message is written to the socket
2603  * without interruption.
2604  *
2605  * Return values:
2606  *   %0 if the message was sent successfully
2607  *   %ENOTCONN if the message was not sent
2608  */
2609 static int bc_send_request(struct rpc_rqst *req)
2610 {
2611         struct svc_xprt *xprt;
2612         int len;
2613
2614         /*
2615          * Get the server socket associated with this callback xprt
2616          */
2617         xprt = req->rq_xprt->bc_xprt;
2618
2619         /*
2620          * Grab the mutex to serialize data as the connection is shared
2621          * with the fore channel
2622          */
2623         mutex_lock(&xprt->xpt_mutex);
2624         if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2625                 len = -ENOTCONN;
2626         else
2627                 len = bc_sendto(req);
2628         mutex_unlock(&xprt->xpt_mutex);
2629
2630         if (len > 0)
2631                 len = 0;
2632
2633         return len;
2634 }
2635
2636 /*
2637  * The close routine. Since this is client initiated, we do nothing
2638  */
2639
2640 static void bc_close(struct rpc_xprt *xprt)
2641 {
2642         xprt_disconnect_done(xprt);
2643 }
2644
2645 /*
2646  * The xprt destroy routine. Again, because this connection is client
2647  * initiated, we do nothing
2648  */
2649
2650 static void bc_destroy(struct rpc_xprt *xprt)
2651 {
2652         dprintk("RPC:       bc_destroy xprt %p\n", xprt);
2653
2654         xs_xprt_free(xprt);
2655         module_put(THIS_MODULE);
2656 }
2657
2658 static const struct rpc_xprt_ops xs_local_ops = {
2659         .reserve_xprt           = xprt_reserve_xprt,
2660         .release_xprt           = xprt_release_xprt,
2661         .alloc_slot             = xprt_alloc_slot,
2662         .free_slot              = xprt_free_slot,
2663         .rpcbind                = xs_local_rpcbind,
2664         .set_port               = xs_local_set_port,
2665         .connect                = xs_local_connect,
2666         .buf_alloc              = rpc_malloc,
2667         .buf_free               = rpc_free,
2668         .prepare_request        = xs_stream_prepare_request,
2669         .send_request           = xs_local_send_request,
2670         .wait_for_reply_request = xprt_wait_for_reply_request_def,
2671         .close                  = xs_close,
2672         .destroy                = xs_destroy,
2673         .print_stats            = xs_local_print_stats,
2674         .enable_swap            = xs_enable_swap,
2675         .disable_swap           = xs_disable_swap,
2676 };
2677
2678 static const struct rpc_xprt_ops xs_udp_ops = {
2679         .set_buffer_size        = xs_udp_set_buffer_size,
2680         .reserve_xprt           = xprt_reserve_xprt_cong,
2681         .release_xprt           = xprt_release_xprt_cong,
2682         .alloc_slot             = xprt_alloc_slot,
2683         .free_slot              = xprt_free_slot,
2684         .rpcbind                = rpcb_getport_async,
2685         .set_port               = xs_set_port,
2686         .connect                = xs_connect,
2687         .get_srcaddr            = xs_sock_srcaddr,
2688         .get_srcport            = xs_sock_srcport,
2689         .buf_alloc              = rpc_malloc,
2690         .buf_free               = rpc_free,
2691         .send_request           = xs_udp_send_request,
2692         .wait_for_reply_request = xprt_wait_for_reply_request_rtt,
2693         .timer                  = xs_udp_timer,
2694         .release_request        = xprt_release_rqst_cong,
2695         .close                  = xs_close,
2696         .destroy                = xs_destroy,
2697         .print_stats            = xs_udp_print_stats,
2698         .enable_swap            = xs_enable_swap,
2699         .disable_swap           = xs_disable_swap,
2700         .inject_disconnect      = xs_inject_disconnect,
2701 };
2702
2703 static const struct rpc_xprt_ops xs_tcp_ops = {
2704         .reserve_xprt           = xprt_reserve_xprt,
2705         .release_xprt           = xprt_release_xprt,
2706         .alloc_slot             = xprt_alloc_slot,
2707         .free_slot              = xprt_free_slot,
2708         .rpcbind                = rpcb_getport_async,
2709         .set_port               = xs_set_port,
2710         .connect                = xs_connect,
2711         .get_srcaddr            = xs_sock_srcaddr,
2712         .get_srcport            = xs_sock_srcport,
2713         .buf_alloc              = rpc_malloc,
2714         .buf_free               = rpc_free,
2715         .prepare_request        = xs_stream_prepare_request,
2716         .send_request           = xs_tcp_send_request,
2717         .wait_for_reply_request = xprt_wait_for_reply_request_def,
2718         .close                  = xs_tcp_shutdown,
2719         .destroy                = xs_destroy,
2720         .set_connect_timeout    = xs_tcp_set_connect_timeout,
2721         .print_stats            = xs_tcp_print_stats,
2722         .enable_swap            = xs_enable_swap,
2723         .disable_swap           = xs_disable_swap,
2724         .inject_disconnect      = xs_inject_disconnect,
2725 #ifdef CONFIG_SUNRPC_BACKCHANNEL
2726         .bc_setup               = xprt_setup_bc,
2727         .bc_maxpayload          = xs_tcp_bc_maxpayload,
2728         .bc_num_slots           = xprt_bc_max_slots,
2729         .bc_free_rqst           = xprt_free_bc_rqst,
2730         .bc_destroy             = xprt_destroy_bc,
2731 #endif
2732 };
2733
2734 /*
2735  * The rpc_xprt_ops for the server backchannel
2736  */
2737
2738 static const struct rpc_xprt_ops bc_tcp_ops = {
2739         .reserve_xprt           = xprt_reserve_xprt,
2740         .release_xprt           = xprt_release_xprt,
2741         .alloc_slot             = xprt_alloc_slot,
2742         .free_slot              = xprt_free_slot,
2743         .buf_alloc              = bc_malloc,
2744         .buf_free               = bc_free,
2745         .send_request           = bc_send_request,
2746         .wait_for_reply_request = xprt_wait_for_reply_request_def,
2747         .close                  = bc_close,
2748         .destroy                = bc_destroy,
2749         .print_stats            = xs_tcp_print_stats,
2750         .enable_swap            = xs_enable_swap,
2751         .disable_swap           = xs_disable_swap,
2752         .inject_disconnect      = xs_inject_disconnect,
2753 };
2754
2755 static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2756 {
2757         static const struct sockaddr_in sin = {
2758                 .sin_family             = AF_INET,
2759                 .sin_addr.s_addr        = htonl(INADDR_ANY),
2760         };
2761         static const struct sockaddr_in6 sin6 = {
2762                 .sin6_family            = AF_INET6,
2763                 .sin6_addr              = IN6ADDR_ANY_INIT,
2764         };
2765
2766         switch (family) {
2767         case AF_LOCAL:
2768                 break;
2769         case AF_INET:
2770                 memcpy(sap, &sin, sizeof(sin));
2771                 break;
2772         case AF_INET6:
2773                 memcpy(sap, &sin6, sizeof(sin6));
2774                 break;
2775         default:
2776                 dprintk("RPC:       %s: Bad address family\n", __func__);
2777                 return -EAFNOSUPPORT;
2778         }
2779         return 0;
2780 }
2781
2782 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2783                                       unsigned int slot_table_size,
2784                                       unsigned int max_slot_table_size)
2785 {
2786         struct rpc_xprt *xprt;
2787         struct sock_xprt *new;
2788
2789         if (args->addrlen > sizeof(xprt->addr)) {
2790                 dprintk("RPC:       xs_setup_xprt: address too large\n");
2791                 return ERR_PTR(-EBADF);
2792         }
2793
2794         xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2795                         max_slot_table_size);
2796         if (xprt == NULL) {
2797                 dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2798                                 "rpc_xprt\n");
2799                 return ERR_PTR(-ENOMEM);
2800         }
2801
2802         new = container_of(xprt, struct sock_xprt, xprt);
2803         mutex_init(&new->recv_mutex);
2804         memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2805         xprt->addrlen = args->addrlen;
2806         if (args->srcaddr)
2807                 memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2808         else {
2809                 int err;
2810                 err = xs_init_anyaddr(args->dstaddr->sa_family,
2811                                         (struct sockaddr *)&new->srcaddr);
2812                 if (err != 0) {
2813                         xprt_free(xprt);
2814                         return ERR_PTR(err);
2815                 }
2816         }
2817
2818         return xprt;
2819 }
2820
2821 static const struct rpc_timeout xs_local_default_timeout = {
2822         .to_initval = 10 * HZ,
2823         .to_maxval = 10 * HZ,
2824         .to_retries = 2,
2825 };
2826
2827 /**
2828  * xs_setup_local - Set up transport to use an AF_LOCAL socket
2829  * @args: rpc transport creation arguments
2830  *
2831  * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2832  */
2833 static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2834 {
2835         struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2836         struct sock_xprt *transport;
2837         struct rpc_xprt *xprt;
2838         struct rpc_xprt *ret;
2839
2840         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2841                         xprt_max_tcp_slot_table_entries);
2842         if (IS_ERR(xprt))
2843                 return xprt;
2844         transport = container_of(xprt, struct sock_xprt, xprt);
2845
2846         xprt->prot = 0;
2847         xprt->xprt_class = &xs_local_transport;
2848         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2849
2850         xprt->bind_timeout = XS_BIND_TO;
2851         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2852         xprt->idle_timeout = XS_IDLE_DISC_TO;
2853
2854         xprt->ops = &xs_local_ops;
2855         xprt->timeout = &xs_local_default_timeout;
2856
2857         INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2858         INIT_WORK(&transport->error_worker, xs_error_handle);
2859         INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket);
2860
2861         switch (sun->sun_family) {
2862         case AF_LOCAL:
2863                 if (sun->sun_path[0] != '/') {
2864                         dprintk("RPC:       bad AF_LOCAL address: %s\n",
2865                                         sun->sun_path);
2866                         ret = ERR_PTR(-EINVAL);
2867                         goto out_err;
2868                 }
2869                 xprt_set_bound(xprt);
2870                 xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
2871                 break;
2872         default:
2873                 ret = ERR_PTR(-EAFNOSUPPORT);
2874                 goto out_err;
2875         }
2876
2877         dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
2878                         xprt->address_strings[RPC_DISPLAY_ADDR]);
2879
2880         if (try_module_get(THIS_MODULE))
2881                 return xprt;
2882         ret = ERR_PTR(-EINVAL);
2883 out_err:
2884         xs_xprt_free(xprt);
2885         return ret;
2886 }
2887
2888 static const struct rpc_timeout xs_udp_default_timeout = {
2889         .to_initval = 5 * HZ,
2890         .to_maxval = 30 * HZ,
2891         .to_increment = 5 * HZ,
2892         .to_retries = 5,
2893 };
2894
2895 /**
2896  * xs_setup_udp - Set up transport to use a UDP socket
2897  * @args: rpc transport creation arguments
2898  *
2899  */
2900 static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2901 {
2902         struct sockaddr *addr = args->dstaddr;
2903         struct rpc_xprt *xprt;
2904         struct sock_xprt *transport;
2905         struct rpc_xprt *ret;
2906
2907         xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2908                         xprt_udp_slot_table_entries);
2909         if (IS_ERR(xprt))
2910                 return xprt;
2911         transport = container_of(xprt, struct sock_xprt, xprt);
2912
2913         xprt->prot = IPPROTO_UDP;
2914         xprt->xprt_class = &xs_udp_transport;
2915         /* XXX: header size can vary due to auth type, IPv6, etc. */
2916         xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2917
2918         xprt->bind_timeout = XS_BIND_TO;
2919         xprt->reestablish_timeout = XS_UDP_REEST_TO;
2920         xprt->idle_timeout = XS_IDLE_DISC_TO;
2921
2922         xprt->ops = &xs_udp_ops;
2923
2924         xprt->timeout = &xs_udp_default_timeout;
2925
2926         INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
2927         INIT_WORK(&transport->error_worker, xs_error_handle);
2928         INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
2929
2930         switch (addr->sa_family) {
2931         case AF_INET:
2932                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2933                         xprt_set_bound(xprt);
2934
2935                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2936                 break;
2937         case AF_INET6:
2938                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2939                         xprt_set_bound(xprt);
2940
2941                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2942                 break;
2943         default:
2944                 ret = ERR_PTR(-EAFNOSUPPORT);
2945                 goto out_err;
2946         }
2947
2948         if (xprt_bound(xprt))
2949                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2950                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2951                                 xprt->address_strings[RPC_DISPLAY_PORT],
2952                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2953         else
2954                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2955                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2956                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2957
2958         if (try_module_get(THIS_MODULE))
2959                 return xprt;
2960         ret = ERR_PTR(-EINVAL);
2961 out_err:
2962         xs_xprt_free(xprt);
2963         return ret;
2964 }
2965
2966 static const struct rpc_timeout xs_tcp_default_timeout = {
2967         .to_initval = 60 * HZ,
2968         .to_maxval = 60 * HZ,
2969         .to_retries = 2,
2970 };
2971
2972 /**
2973  * xs_setup_tcp - Set up transport to use a TCP socket
2974  * @args: rpc transport creation arguments
2975  *
2976  */
2977 static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2978 {
2979         struct sockaddr *addr = args->dstaddr;
2980         struct rpc_xprt *xprt;
2981         struct sock_xprt *transport;
2982         struct rpc_xprt *ret;
2983         unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
2984
2985         if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
2986                 max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
2987
2988         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2989                         max_slot_table_size);
2990         if (IS_ERR(xprt))
2991                 return xprt;
2992         transport = container_of(xprt, struct sock_xprt, xprt);
2993
2994         xprt->prot = IPPROTO_TCP;
2995         xprt->xprt_class = &xs_tcp_transport;
2996         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2997
2998         xprt->bind_timeout = XS_BIND_TO;
2999         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
3000         xprt->idle_timeout = XS_IDLE_DISC_TO;
3001
3002         xprt->ops = &xs_tcp_ops;
3003         xprt->timeout = &xs_tcp_default_timeout;
3004
3005         xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
3006         xprt->connect_timeout = xprt->timeout->to_initval *
3007                 (xprt->timeout->to_retries + 1);
3008
3009         INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
3010         INIT_WORK(&transport->error_worker, xs_error_handle);
3011         INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
3012
3013         switch (addr->sa_family) {
3014         case AF_INET:
3015                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3016                         xprt_set_bound(xprt);
3017
3018                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
3019                 break;
3020         case AF_INET6:
3021                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3022                         xprt_set_bound(xprt);
3023
3024                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
3025                 break;
3026         default:
3027                 ret = ERR_PTR(-EAFNOSUPPORT);
3028                 goto out_err;
3029         }
3030
3031         if (xprt_bound(xprt))
3032                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3033                                 xprt->address_strings[RPC_DISPLAY_ADDR],
3034                                 xprt->address_strings[RPC_DISPLAY_PORT],
3035                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
3036         else
3037                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3038                                 xprt->address_strings[RPC_DISPLAY_ADDR],
3039                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
3040
3041         if (try_module_get(THIS_MODULE))
3042                 return xprt;
3043         ret = ERR_PTR(-EINVAL);
3044 out_err:
3045         xs_xprt_free(xprt);
3046         return ret;
3047 }
3048
3049 /**
3050  * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
3051  * @args: rpc transport creation arguments
3052  *
3053  */
3054 static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
3055 {
3056         struct sockaddr *addr = args->dstaddr;
3057         struct rpc_xprt *xprt;
3058         struct sock_xprt *transport;
3059         struct svc_sock *bc_sock;
3060         struct rpc_xprt *ret;
3061
3062         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3063                         xprt_tcp_slot_table_entries);
3064         if (IS_ERR(xprt))
3065                 return xprt;
3066         transport = container_of(xprt, struct sock_xprt, xprt);
3067
3068         xprt->prot = IPPROTO_TCP;
3069         xprt->xprt_class = &xs_bc_tcp_transport;
3070         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3071         xprt->timeout = &xs_tcp_default_timeout;
3072
3073         /* backchannel */
3074         xprt_set_bound(xprt);
3075         xprt->bind_timeout = 0;
3076         xprt->reestablish_timeout = 0;
3077         xprt->idle_timeout = 0;
3078
3079         xprt->ops = &bc_tcp_ops;
3080
3081         switch (addr->sa_family) {
3082         case AF_INET:
3083                 xs_format_peer_addresses(xprt, "tcp",
3084                                          RPCBIND_NETID_TCP);
3085                 break;
3086         case AF_INET6:
3087                 xs_format_peer_addresses(xprt, "tcp",
3088                                    RPCBIND_NETID_TCP6);
3089                 break;
3090         default:
3091                 ret = ERR_PTR(-EAFNOSUPPORT);
3092                 goto out_err;
3093         }
3094
3095         dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3096                         xprt->address_strings[RPC_DISPLAY_ADDR],
3097                         xprt->address_strings[RPC_DISPLAY_PORT],
3098                         xprt->address_strings[RPC_DISPLAY_PROTO]);
3099
3100         /*
3101          * Once we've associated a backchannel xprt with a connection,
3102          * we want to keep it around as long as the connection lasts,
3103          * in case we need to start using it for a backchannel again;
3104          * this reference won't be dropped until bc_xprt is destroyed.
3105          */
3106         xprt_get(xprt);
3107         args->bc_xprt->xpt_bc_xprt = xprt;
3108         xprt->bc_xprt = args->bc_xprt;
3109         bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3110         transport->sock = bc_sock->sk_sock;
3111         transport->inet = bc_sock->sk_sk;
3112
3113         /*
3114          * Since we don't want connections for the backchannel, we set
3115          * the xprt status to connected
3116          */
3117         xprt_set_connected(xprt);
3118
3119         if (try_module_get(THIS_MODULE))
3120                 return xprt;
3121
3122         args->bc_xprt->xpt_bc_xprt = NULL;
3123         args->bc_xprt->xpt_bc_xps = NULL;
3124         xprt_put(xprt);
3125         ret = ERR_PTR(-EINVAL);
3126 out_err:
3127         xs_xprt_free(xprt);
3128         return ret;
3129 }
3130
3131 static struct xprt_class        xs_local_transport = {
3132         .list           = LIST_HEAD_INIT(xs_local_transport.list),
3133         .name           = "named UNIX socket",
3134         .owner          = THIS_MODULE,
3135         .ident          = XPRT_TRANSPORT_LOCAL,
3136         .setup          = xs_setup_local,
3137         .netid          = { "" },
3138 };
3139
3140 static struct xprt_class        xs_udp_transport = {
3141         .list           = LIST_HEAD_INIT(xs_udp_transport.list),
3142         .name           = "udp",
3143         .owner          = THIS_MODULE,
3144         .ident          = XPRT_TRANSPORT_UDP,
3145         .setup          = xs_setup_udp,
3146         .netid          = { "udp", "udp6", "" },
3147 };
3148
3149 static struct xprt_class        xs_tcp_transport = {
3150         .list           = LIST_HEAD_INIT(xs_tcp_transport.list),
3151         .name           = "tcp",
3152         .owner          = THIS_MODULE,
3153         .ident          = XPRT_TRANSPORT_TCP,
3154         .setup          = xs_setup_tcp,
3155         .netid          = { "tcp", "tcp6", "" },
3156 };
3157
3158 static struct xprt_class        xs_bc_tcp_transport = {
3159         .list           = LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3160         .name           = "tcp NFSv4.1 backchannel",
3161         .owner          = THIS_MODULE,
3162         .ident          = XPRT_TRANSPORT_BC_TCP,
3163         .setup          = xs_setup_bc_tcp,
3164         .netid          = { "" },
3165 };
3166
3167 /**
3168  * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3169  *
3170  */
3171 int init_socket_xprt(void)
3172 {
3173         if (!sunrpc_table_header)
3174                 sunrpc_table_header = register_sysctl_table(sunrpc_table);
3175
3176         xprt_register_transport(&xs_local_transport);
3177         xprt_register_transport(&xs_udp_transport);
3178         xprt_register_transport(&xs_tcp_transport);
3179         xprt_register_transport(&xs_bc_tcp_transport);
3180
3181         return 0;
3182 }
3183
3184 /**
3185  * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3186  *
3187  */
3188 void cleanup_socket_xprt(void)
3189 {
3190         if (sunrpc_table_header) {
3191                 unregister_sysctl_table(sunrpc_table_header);
3192                 sunrpc_table_header = NULL;
3193         }
3194
3195         xprt_unregister_transport(&xs_local_transport);
3196         xprt_unregister_transport(&xs_udp_transport);
3197         xprt_unregister_transport(&xs_tcp_transport);
3198         xprt_unregister_transport(&xs_bc_tcp_transport);
3199 }
3200
3201 static int param_set_portnr(const char *val, const struct kernel_param *kp)
3202 {
3203         return param_set_uint_minmax(val, kp,
3204                         RPC_MIN_RESVPORT,
3205                         RPC_MAX_RESVPORT);
3206 }
3207
3208 static const struct kernel_param_ops param_ops_portnr = {
3209         .set = param_set_portnr,
3210         .get = param_get_uint,
3211 };
3212
3213 #define param_check_portnr(name, p) \
3214         __param_check(name, p, unsigned int);
3215
3216 module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3217 module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3218
3219 static int param_set_slot_table_size(const char *val,
3220                                      const struct kernel_param *kp)
3221 {
3222         return param_set_uint_minmax(val, kp,
3223                         RPC_MIN_SLOT_TABLE,
3224                         RPC_MAX_SLOT_TABLE);
3225 }
3226
3227 static const struct kernel_param_ops param_ops_slot_table_size = {
3228         .set = param_set_slot_table_size,
3229         .get = param_get_uint,
3230 };
3231
3232 #define param_check_slot_table_size(name, p) \
3233         __param_check(name, p, unsigned int);
3234
3235 static int param_set_max_slot_table_size(const char *val,
3236                                      const struct kernel_param *kp)
3237 {
3238         return param_set_uint_minmax(val, kp,
3239                         RPC_MIN_SLOT_TABLE,
3240                         RPC_MAX_SLOT_TABLE_LIMIT);
3241 }
3242
3243 static const struct kernel_param_ops param_ops_max_slot_table_size = {
3244         .set = param_set_max_slot_table_size,
3245         .get = param_get_uint,
3246 };
3247
3248 #define param_check_max_slot_table_size(name, p) \
3249         __param_check(name, p, unsigned int);
3250
3251 module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3252                    slot_table_size, 0644);
3253 module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3254                    max_slot_table_size, 0644);
3255 module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3256                    slot_table_size, 0644);