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v5.9
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * linux/net/sunrpc/xprtsock.c
   4 *
   5 * Client-side transport implementation for sockets.
   6 *
   7 * TCP callback races fixes (C) 1998 Red Hat
   8 * TCP send fixes (C) 1998 Red Hat
   9 * TCP NFS related read + write fixes
  10 *  (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
  11 *
  12 * Rewrite of larges part of the code in order to stabilize TCP stuff.
  13 * Fix behaviour when socket buffer is full.
  14 *  (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no>
  15 *
  16 * IP socket transport implementation, (C) 2005 Chuck Lever <cel@netapp.com>
  17 *
  18 * IPv6 support contributed by Gilles Quillard, Bull Open Source, 2005.
  19 *   <gilles.quillard@bull.net>
  20 */
  21
  22#include <linux/types.h>
  23#include <linux/string.h>
  24#include <linux/slab.h>
  25#include <linux/module.h>
  26#include <linux/capability.h>
  27#include <linux/pagemap.h>
  28#include <linux/errno.h>
  29#include <linux/socket.h>
  30#include <linux/in.h>
  31#include <linux/net.h>
  32#include <linux/mm.h>
  33#include <linux/un.h>
  34#include <linux/udp.h>
  35#include <linux/tcp.h>
  36#include <linux/sunrpc/clnt.h>
  37#include <linux/sunrpc/addr.h>
  38#include <linux/sunrpc/sched.h>
  39#include <linux/sunrpc/svcsock.h>
  40#include <linux/sunrpc/xprtsock.h>
  41#include <linux/file.h>
  42#ifdef CONFIG_SUNRPC_BACKCHANNEL
  43#include <linux/sunrpc/bc_xprt.h>
  44#endif
  45
  46#include <net/sock.h>
  47#include <net/checksum.h>
  48#include <net/udp.h>
  49#include <net/tcp.h>
  50#include <linux/bvec.h>
  51#include <linux/highmem.h>
  52#include <linux/uio.h>
  53#include <linux/sched/mm.h>
  54
  55#include <trace/events/sunrpc.h>
  56
  57#include "socklib.h"
  58#include "sunrpc.h"
  59
  60static void xs_close(struct rpc_xprt *xprt);
  61static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
  62		struct socket *sock);
  63
  64/*
  65 * xprtsock tunables
  66 */
  67static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  68static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
  69static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
  70
  71static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
  72static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
  73
  74#define XS_TCP_LINGER_TO	(15U * HZ)
  75static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
  76
  77/*
  78 * We can register our own files under /proc/sys/sunrpc by
  79 * calling register_sysctl_table() again.  The files in that
  80 * directory become the union of all files registered there.
  81 *
  82 * We simply need to make sure that we don't collide with
  83 * someone else's file names!
  84 */
  85
  86static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
  87static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
  88static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
  89static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
  90static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
  91
  92static struct ctl_table_header *sunrpc_table_header;
  93
  94/*
  95 * FIXME: changing the UDP slot table size should also resize the UDP
  96 *        socket buffers for existing UDP transports
  97 */
  98static struct ctl_table xs_tunables_table[] = {
  99	{
 100		.procname	= "udp_slot_table_entries",
 101		.data		= &xprt_udp_slot_table_entries,
 102		.maxlen		= sizeof(unsigned int),
 103		.mode		= 0644,
 104		.proc_handler	= proc_dointvec_minmax,
 105		.extra1		= &min_slot_table_size,
 106		.extra2		= &max_slot_table_size
 107	},
 108	{
 109		.procname	= "tcp_slot_table_entries",
 110		.data		= &xprt_tcp_slot_table_entries,
 111		.maxlen		= sizeof(unsigned int),
 112		.mode		= 0644,
 113		.proc_handler	= proc_dointvec_minmax,
 114		.extra1		= &min_slot_table_size,
 115		.extra2		= &max_slot_table_size
 116	},
 117	{
 118		.procname	= "tcp_max_slot_table_entries",
 119		.data		= &xprt_max_tcp_slot_table_entries,
 120		.maxlen		= sizeof(unsigned int),
 121		.mode		= 0644,
 122		.proc_handler	= proc_dointvec_minmax,
 123		.extra1		= &min_slot_table_size,
 124		.extra2		= &max_tcp_slot_table_limit
 125	},
 126	{
 127		.procname	= "min_resvport",
 128		.data		= &xprt_min_resvport,
 129		.maxlen		= sizeof(unsigned int),
 130		.mode		= 0644,
 131		.proc_handler	= proc_dointvec_minmax,
 132		.extra1		= &xprt_min_resvport_limit,
 133		.extra2		= &xprt_max_resvport_limit
 134	},
 135	{
 136		.procname	= "max_resvport",
 137		.data		= &xprt_max_resvport,
 138		.maxlen		= sizeof(unsigned int),
 139		.mode		= 0644,
 140		.proc_handler	= proc_dointvec_minmax,
 141		.extra1		= &xprt_min_resvport_limit,
 142		.extra2		= &xprt_max_resvport_limit
 143	},
 144	{
 145		.procname	= "tcp_fin_timeout",
 146		.data		= &xs_tcp_fin_timeout,
 147		.maxlen		= sizeof(xs_tcp_fin_timeout),
 148		.mode		= 0644,
 149		.proc_handler	= proc_dointvec_jiffies,
 150	},
 151	{ },
 152};
 153
 154static struct ctl_table sunrpc_table[] = {
 155	{
 156		.procname	= "sunrpc",
 157		.mode		= 0555,
 158		.child		= xs_tunables_table
 159	},
 160	{ },
 161};
 162
 163/*
 164 * Wait duration for a reply from the RPC portmapper.
 165 */
 166#define XS_BIND_TO		(60U * HZ)
 167
 168/*
 169 * Delay if a UDP socket connect error occurs.  This is most likely some
 170 * kind of resource problem on the local host.
 171 */
 172#define XS_UDP_REEST_TO		(2U * HZ)
 173
 174/*
 175 * The reestablish timeout allows clients to delay for a bit before attempting
 176 * to reconnect to a server that just dropped our connection.
 177 *
 178 * We implement an exponential backoff when trying to reestablish a TCP
 179 * transport connection with the server.  Some servers like to drop a TCP
 180 * connection when they are overworked, so we start with a short timeout and
 181 * increase over time if the server is down or not responding.
 182 */
 183#define XS_TCP_INIT_REEST_TO	(3U * HZ)
 184
 185/*
 186 * TCP idle timeout; client drops the transport socket if it is idle
 187 * for this long.  Note that we also timeout UDP sockets to prevent
 188 * holding port numbers when there is no RPC traffic.
 189 */
 190#define XS_IDLE_DISC_TO		(5U * 60 * HZ)
 191
 192#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 193# undef  RPC_DEBUG_DATA
 194# define RPCDBG_FACILITY	RPCDBG_TRANS
 195#endif
 196
 197#ifdef RPC_DEBUG_DATA
 198static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 199{
 200	u8 *buf = (u8 *) packet;
 201	int j;
 202
 203	dprintk("RPC:       %s\n", msg);
 204	for (j = 0; j < count && j < 128; j += 4) {
 205		if (!(j & 31)) {
 206			if (j)
 207				dprintk("\n");
 208			dprintk("0x%04x ", j);
 209		}
 210		dprintk("%02x%02x%02x%02x ",
 211			buf[j], buf[j+1], buf[j+2], buf[j+3]);
 212	}
 213	dprintk("\n");
 214}
 215#else
 216static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 217{
 218	/* NOP */
 219}
 220#endif
 221
 222static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
 223{
 224	return (struct rpc_xprt *) sk->sk_user_data;
 225}
 226
 227static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
 228{
 229	return (struct sockaddr *) &xprt->addr;
 230}
 231
 232static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
 233{
 234	return (struct sockaddr_un *) &xprt->addr;
 235}
 236
 237static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
 238{
 239	return (struct sockaddr_in *) &xprt->addr;
 240}
 241
 242static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
 243{
 244	return (struct sockaddr_in6 *) &xprt->addr;
 245}
 246
 247static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
 248{
 249	struct sockaddr *sap = xs_addr(xprt);
 250	struct sockaddr_in6 *sin6;
 251	struct sockaddr_in *sin;
 252	struct sockaddr_un *sun;
 253	char buf[128];
 254
 255	switch (sap->sa_family) {
 256	case AF_LOCAL:
 257		sun = xs_addr_un(xprt);
 258		strlcpy(buf, sun->sun_path, sizeof(buf));
 259		xprt->address_strings[RPC_DISPLAY_ADDR] =
 260						kstrdup(buf, GFP_KERNEL);
 261		break;
 262	case AF_INET:
 263		(void)rpc_ntop(sap, buf, sizeof(buf));
 264		xprt->address_strings[RPC_DISPLAY_ADDR] =
 265						kstrdup(buf, GFP_KERNEL);
 266		sin = xs_addr_in(xprt);
 267		snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
 268		break;
 269	case AF_INET6:
 270		(void)rpc_ntop(sap, buf, sizeof(buf));
 271		xprt->address_strings[RPC_DISPLAY_ADDR] =
 272						kstrdup(buf, GFP_KERNEL);
 273		sin6 = xs_addr_in6(xprt);
 274		snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
 275		break;
 276	default:
 277		BUG();
 278	}
 279
 280	xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
 281}
 282
 283static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
 284{
 285	struct sockaddr *sap = xs_addr(xprt);
 286	char buf[128];
 287
 288	snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
 289	xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
 290
 291	snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
 292	xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
 293}
 294
 295static void xs_format_peer_addresses(struct rpc_xprt *xprt,
 296				     const char *protocol,
 297				     const char *netid)
 298{
 299	xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
 300	xprt->address_strings[RPC_DISPLAY_NETID] = netid;
 301	xs_format_common_peer_addresses(xprt);
 302	xs_format_common_peer_ports(xprt);
 303}
 304
 305static void xs_update_peer_port(struct rpc_xprt *xprt)
 306{
 307	kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
 308	kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
 309
 310	xs_format_common_peer_ports(xprt);
 311}
 312
 313static void xs_free_peer_addresses(struct rpc_xprt *xprt)
 314{
 315	unsigned int i;
 316
 317	for (i = 0; i < RPC_DISPLAY_MAX; i++)
 318		switch (i) {
 319		case RPC_DISPLAY_PROTO:
 320		case RPC_DISPLAY_NETID:
 321			continue;
 322		default:
 323			kfree(xprt->address_strings[i]);
 324		}
 325}
 326
 327static size_t
 328xs_alloc_sparse_pages(struct xdr_buf *buf, size_t want, gfp_t gfp)
 329{
 330	size_t i,n;
 331
 332	if (!want || !(buf->flags & XDRBUF_SPARSE_PAGES))
 333		return want;
 334	n = (buf->page_base + want + PAGE_SIZE - 1) >> PAGE_SHIFT;
 335	for (i = 0; i < n; i++) {
 336		if (buf->pages[i])
 337			continue;
 338		buf->bvec[i].bv_page = buf->pages[i] = alloc_page(gfp);
 339		if (!buf->pages[i]) {
 340			i *= PAGE_SIZE;
 341			return i > buf->page_base ? i - buf->page_base : 0;
 342		}
 343	}
 344	return want;
 345}
 346
 347static ssize_t
 348xs_sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags, size_t seek)
 349{
 350	ssize_t ret;
 351	if (seek != 0)
 352		iov_iter_advance(&msg->msg_iter, seek);
 353	ret = sock_recvmsg(sock, msg, flags);
 354	return ret > 0 ? ret + seek : ret;
 355}
 356
 357static ssize_t
 358xs_read_kvec(struct socket *sock, struct msghdr *msg, int flags,
 359		struct kvec *kvec, size_t count, size_t seek)
 360{
 361	iov_iter_kvec(&msg->msg_iter, READ, kvec, 1, count);
 362	return xs_sock_recvmsg(sock, msg, flags, seek);
 363}
 364
 365static ssize_t
 366xs_read_bvec(struct socket *sock, struct msghdr *msg, int flags,
 367		struct bio_vec *bvec, unsigned long nr, size_t count,
 368		size_t seek)
 369{
 370	iov_iter_bvec(&msg->msg_iter, READ, bvec, nr, count);
 371	return xs_sock_recvmsg(sock, msg, flags, seek);
 372}
 373
 374static ssize_t
 375xs_read_discard(struct socket *sock, struct msghdr *msg, int flags,
 376		size_t count)
 377{
 378	iov_iter_discard(&msg->msg_iter, READ, count);
 379	return sock_recvmsg(sock, msg, flags);
 380}
 381
 382#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
 383static void
 384xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
 385{
 386	struct bvec_iter bi = {
 387		.bi_size = count,
 388	};
 389	struct bio_vec bv;
 390
 391	bvec_iter_advance(bvec, &bi, seek & PAGE_MASK);
 392	for_each_bvec(bv, bvec, bi, bi)
 393		flush_dcache_page(bv.bv_page);
 394}
 395#else
 396static inline void
 397xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
 398{
 399}
 400#endif
 401
 402static ssize_t
 403xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags,
 404		struct xdr_buf *buf, size_t count, size_t seek, size_t *read)
 405{
 406	size_t want, seek_init = seek, offset = 0;
 407	ssize_t ret;
 408
 409	want = min_t(size_t, count, buf->head[0].iov_len);
 410	if (seek < want) {
 411		ret = xs_read_kvec(sock, msg, flags, &buf->head[0], want, seek);
 412		if (ret <= 0)
 413			goto sock_err;
 414		offset += ret;
 415		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 416			goto out;
 417		if (ret != want)
 418			goto out;
 419		seek = 0;
 420	} else {
 421		seek -= want;
 422		offset += want;
 423	}
 424
 425	want = xs_alloc_sparse_pages(buf,
 426			min_t(size_t, count - offset, buf->page_len),
 427			GFP_KERNEL);
 428	if (seek < want) {
 429		ret = xs_read_bvec(sock, msg, flags, buf->bvec,
 430				xdr_buf_pagecount(buf),
 431				want + buf->page_base,
 432				seek + buf->page_base);
 433		if (ret <= 0)
 434			goto sock_err;
 435		xs_flush_bvec(buf->bvec, ret, seek + buf->page_base);
 436		offset += ret - buf->page_base;
 437		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 438			goto out;
 439		if (ret != want)
 440			goto out;
 441		seek = 0;
 442	} else {
 443		seek -= want;
 444		offset += want;
 445	}
 446
 447	want = min_t(size_t, count - offset, buf->tail[0].iov_len);
 448	if (seek < want) {
 449		ret = xs_read_kvec(sock, msg, flags, &buf->tail[0], want, seek);
 450		if (ret <= 0)
 451			goto sock_err;
 452		offset += ret;
 453		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 454			goto out;
 455		if (ret != want)
 456			goto out;
 457	} else if (offset < seek_init)
 458		offset = seek_init;
 459	ret = -EMSGSIZE;
 460out:
 461	*read = offset - seek_init;
 462	return ret;
 463sock_err:
 464	offset += seek;
 465	goto out;
 466}
 467
 468static void
 469xs_read_header(struct sock_xprt *transport, struct xdr_buf *buf)
 470{
 471	if (!transport->recv.copied) {
 472		if (buf->head[0].iov_len >= transport->recv.offset)
 473			memcpy(buf->head[0].iov_base,
 474					&transport->recv.xid,
 475					transport->recv.offset);
 476		transport->recv.copied = transport->recv.offset;
 477	}
 478}
 479
 480static bool
 481xs_read_stream_request_done(struct sock_xprt *transport)
 482{
 483	return transport->recv.fraghdr & cpu_to_be32(RPC_LAST_STREAM_FRAGMENT);
 484}
 485
 486static void
 487xs_read_stream_check_eor(struct sock_xprt *transport,
 488		struct msghdr *msg)
 489{
 490	if (xs_read_stream_request_done(transport))
 491		msg->msg_flags |= MSG_EOR;
 492}
 493
 494static ssize_t
 495xs_read_stream_request(struct sock_xprt *transport, struct msghdr *msg,
 496		int flags, struct rpc_rqst *req)
 497{
 498	struct xdr_buf *buf = &req->rq_private_buf;
 499	size_t want, read;
 500	ssize_t ret;
 501
 502	xs_read_header(transport, buf);
 503
 504	want = transport->recv.len - transport->recv.offset;
 505	if (want != 0) {
 506		ret = xs_read_xdr_buf(transport->sock, msg, flags, buf,
 507				transport->recv.copied + want,
 508				transport->recv.copied,
 509				&read);
 510		transport->recv.offset += read;
 511		transport->recv.copied += read;
 512	}
 513
 514	if (transport->recv.offset == transport->recv.len)
 515		xs_read_stream_check_eor(transport, msg);
 516
 517	if (want == 0)
 518		return 0;
 519
 520	switch (ret) {
 521	default:
 522		break;
 523	case -EFAULT:
 524	case -EMSGSIZE:
 525		msg->msg_flags |= MSG_TRUNC;
 526		return read;
 527	case 0:
 528		return -ESHUTDOWN;
 529	}
 530	return ret < 0 ? ret : read;
 531}
 532
 533static size_t
 534xs_read_stream_headersize(bool isfrag)
 535{
 536	if (isfrag)
 537		return sizeof(__be32);
 538	return 3 * sizeof(__be32);
 539}
 540
 541static ssize_t
 542xs_read_stream_header(struct sock_xprt *transport, struct msghdr *msg,
 543		int flags, size_t want, size_t seek)
 544{
 545	struct kvec kvec = {
 546		.iov_base = &transport->recv.fraghdr,
 547		.iov_len = want,
 548	};
 549	return xs_read_kvec(transport->sock, msg, flags, &kvec, want, seek);
 550}
 551
 552#if defined(CONFIG_SUNRPC_BACKCHANNEL)
 553static ssize_t
 554xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 555{
 556	struct rpc_xprt *xprt = &transport->xprt;
 557	struct rpc_rqst *req;
 558	ssize_t ret;
 559
 560	/* Look up and lock the request corresponding to the given XID */
 561	req = xprt_lookup_bc_request(xprt, transport->recv.xid);
 562	if (!req) {
 563		printk(KERN_WARNING "Callback slot table overflowed\n");
 564		return -ESHUTDOWN;
 565	}
 566	if (transport->recv.copied && !req->rq_private_buf.len)
 567		return -ESHUTDOWN;
 568
 569	ret = xs_read_stream_request(transport, msg, flags, req);
 570	if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 571		xprt_complete_bc_request(req, transport->recv.copied);
 572	else
 573		req->rq_private_buf.len = transport->recv.copied;
 574
 575	return ret;
 576}
 577#else /* CONFIG_SUNRPC_BACKCHANNEL */
 578static ssize_t
 579xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 580{
 581	return -ESHUTDOWN;
 582}
 583#endif /* CONFIG_SUNRPC_BACKCHANNEL */
 584
 585static ssize_t
 586xs_read_stream_reply(struct sock_xprt *transport, struct msghdr *msg, int flags)
 587{
 588	struct rpc_xprt *xprt = &transport->xprt;
 589	struct rpc_rqst *req;
 590	ssize_t ret = 0;
 591
 592	/* Look up and lock the request corresponding to the given XID */
 593	spin_lock(&xprt->queue_lock);
 594	req = xprt_lookup_rqst(xprt, transport->recv.xid);
 595	if (!req || (transport->recv.copied && !req->rq_private_buf.len)) {
 596		msg->msg_flags |= MSG_TRUNC;
 597		goto out;
 598	}
 599	xprt_pin_rqst(req);
 600	spin_unlock(&xprt->queue_lock);
 601
 602	ret = xs_read_stream_request(transport, msg, flags, req);
 603
 604	spin_lock(&xprt->queue_lock);
 605	if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 606		xprt_complete_rqst(req->rq_task, transport->recv.copied);
 607	else
 608		req->rq_private_buf.len = transport->recv.copied;
 609	xprt_unpin_rqst(req);
 610out:
 611	spin_unlock(&xprt->queue_lock);
 612	return ret;
 613}
 614
 615static ssize_t
 616xs_read_stream(struct sock_xprt *transport, int flags)
 617{
 618	struct msghdr msg = { 0 };
 619	size_t want, read = 0;
 620	ssize_t ret = 0;
 621
 622	if (transport->recv.len == 0) {
 623		want = xs_read_stream_headersize(transport->recv.copied != 0);
 624		ret = xs_read_stream_header(transport, &msg, flags, want,
 625				transport->recv.offset);
 626		if (ret <= 0)
 627			goto out_err;
 628		transport->recv.offset = ret;
 629		if (transport->recv.offset != want)
 630			return transport->recv.offset;
 631		transport->recv.len = be32_to_cpu(transport->recv.fraghdr) &
 632			RPC_FRAGMENT_SIZE_MASK;
 633		transport->recv.offset -= sizeof(transport->recv.fraghdr);
 634		read = ret;
 635	}
 636
 637	switch (be32_to_cpu(transport->recv.calldir)) {
 638	default:
 639		msg.msg_flags |= MSG_TRUNC;
 640		break;
 641	case RPC_CALL:
 642		ret = xs_read_stream_call(transport, &msg, flags);
 643		break;
 644	case RPC_REPLY:
 645		ret = xs_read_stream_reply(transport, &msg, flags);
 646	}
 647	if (msg.msg_flags & MSG_TRUNC) {
 648		transport->recv.calldir = cpu_to_be32(-1);
 649		transport->recv.copied = -1;
 650	}
 651	if (ret < 0)
 652		goto out_err;
 653	read += ret;
 654	if (transport->recv.offset < transport->recv.len) {
 655		if (!(msg.msg_flags & MSG_TRUNC))
 656			return read;
 657		msg.msg_flags = 0;
 658		ret = xs_read_discard(transport->sock, &msg, flags,
 659				transport->recv.len - transport->recv.offset);
 660		if (ret <= 0)
 661			goto out_err;
 662		transport->recv.offset += ret;
 663		read += ret;
 664		if (transport->recv.offset != transport->recv.len)
 665			return read;
 666	}
 667	if (xs_read_stream_request_done(transport)) {
 668		trace_xs_stream_read_request(transport);
 669		transport->recv.copied = 0;
 670	}
 671	transport->recv.offset = 0;
 672	transport->recv.len = 0;
 673	return read;
 674out_err:
 675	return ret != 0 ? ret : -ESHUTDOWN;
 676}
 677
 678static __poll_t xs_poll_socket(struct sock_xprt *transport)
 679{
 680	return transport->sock->ops->poll(transport->file, transport->sock,
 681			NULL);
 682}
 683
 684static bool xs_poll_socket_readable(struct sock_xprt *transport)
 685{
 686	__poll_t events = xs_poll_socket(transport);
 687
 688	return (events & (EPOLLIN | EPOLLRDNORM)) && !(events & EPOLLRDHUP);
 689}
 690
 691static void xs_poll_check_readable(struct sock_xprt *transport)
 692{
 693
 694	clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
 695	if (!xs_poll_socket_readable(transport))
 696		return;
 697	if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
 698		queue_work(xprtiod_workqueue, &transport->recv_worker);
 699}
 700
 701static void xs_stream_data_receive(struct sock_xprt *transport)
 702{
 703	size_t read = 0;
 704	ssize_t ret = 0;
 705
 706	mutex_lock(&transport->recv_mutex);
 707	if (transport->sock == NULL)
 708		goto out;
 709	for (;;) {
 710		ret = xs_read_stream(transport, MSG_DONTWAIT);
 711		if (ret < 0)
 712			break;
 713		read += ret;
 714		cond_resched();
 715	}
 716	if (ret == -ESHUTDOWN)
 717		kernel_sock_shutdown(transport->sock, SHUT_RDWR);
 718	else
 719		xs_poll_check_readable(transport);
 720out:
 721	mutex_unlock(&transport->recv_mutex);
 722	trace_xs_stream_read_data(&transport->xprt, ret, read);
 723}
 724
 725static void xs_stream_data_receive_workfn(struct work_struct *work)
 726{
 727	struct sock_xprt *transport =
 728		container_of(work, struct sock_xprt, recv_worker);
 729	unsigned int pflags = memalloc_nofs_save();
 730
 731	xs_stream_data_receive(transport);
 732	memalloc_nofs_restore(pflags);
 733}
 734
 735static void
 736xs_stream_reset_connect(struct sock_xprt *transport)
 737{
 738	transport->recv.offset = 0;
 739	transport->recv.len = 0;
 740	transport->recv.copied = 0;
 741	transport->xmit.offset = 0;
 742}
 743
 744static void
 745xs_stream_start_connect(struct sock_xprt *transport)
 746{
 747	transport->xprt.stat.connect_count++;
 748	transport->xprt.stat.connect_start = jiffies;
 749}
 750
 751#define XS_SENDMSG_FLAGS	(MSG_DONTWAIT | MSG_NOSIGNAL)
 752
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 753/**
 754 * xs_nospace - handle transmit was incomplete
 755 * @req: pointer to RPC request
 756 *
 757 */
 758static int xs_nospace(struct rpc_rqst *req)
 759{
 760	struct rpc_xprt *xprt = req->rq_xprt;
 761	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 762	struct sock *sk = transport->inet;
 763	int ret = -EAGAIN;
 764
 765	dprintk("RPC: %5u xmit incomplete (%u left of %u)\n",
 766			req->rq_task->tk_pid,
 767			req->rq_slen - transport->xmit.offset,
 768			req->rq_slen);
 769
 770	/* Protect against races with write_space */
 771	spin_lock(&xprt->transport_lock);
 772
 773	/* Don't race with disconnect */
 774	if (xprt_connected(xprt)) {
 775		/* wait for more buffer space */
 776		sk->sk_write_pending++;
 777		xprt_wait_for_buffer_space(xprt);
 778	} else
 779		ret = -ENOTCONN;
 780
 781	spin_unlock(&xprt->transport_lock);
 782
 783	/* Race breaker in case memory is freed before above code is called */
 784	if (ret == -EAGAIN) {
 785		struct socket_wq *wq;
 786
 787		rcu_read_lock();
 788		wq = rcu_dereference(sk->sk_wq);
 789		set_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags);
 790		rcu_read_unlock();
 791
 792		sk->sk_write_space(sk);
 793	}
 794	return ret;
 795}
 796
 797static void
 798xs_stream_prepare_request(struct rpc_rqst *req)
 799{
 800	xdr_free_bvec(&req->rq_rcv_buf);
 801	req->rq_task->tk_status = xdr_alloc_bvec(&req->rq_rcv_buf, GFP_KERNEL);
 802}
 803
 804/*
 805 * Determine if the previous message in the stream was aborted before it
 806 * could complete transmission.
 807 */
 808static bool
 809xs_send_request_was_aborted(struct sock_xprt *transport, struct rpc_rqst *req)
 810{
 811	return transport->xmit.offset != 0 && req->rq_bytes_sent == 0;
 812}
 813
 814/*
 815 * Return the stream record marker field for a record of length < 2^31-1
 816 */
 817static rpc_fraghdr
 818xs_stream_record_marker(struct xdr_buf *xdr)
 819{
 820	if (!xdr->len)
 821		return 0;
 822	return cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | (u32)xdr->len);
 823}
 824
 825/**
 826 * xs_local_send_request - write an RPC request to an AF_LOCAL socket
 827 * @req: pointer to RPC request
 828 *
 829 * Return values:
 830 *        0:	The request has been sent
 831 *   EAGAIN:	The socket was blocked, please call again later to
 832 *		complete the request
 833 * ENOTCONN:	Caller needs to invoke connect logic then call again
 834 *    other:	Some other error occured, the request was not sent
 835 */
 836static int xs_local_send_request(struct rpc_rqst *req)
 837{
 838	struct rpc_xprt *xprt = req->rq_xprt;
 839	struct sock_xprt *transport =
 840				container_of(xprt, struct sock_xprt, xprt);
 841	struct xdr_buf *xdr = &req->rq_snd_buf;
 842	rpc_fraghdr rm = xs_stream_record_marker(xdr);
 843	unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
 844	struct msghdr msg = {
 845		.msg_flags	= XS_SENDMSG_FLAGS,
 846	};
 847	unsigned int sent;
 848	int status;
 
 849
 850	/* Close the stream if the previous transmission was incomplete */
 851	if (xs_send_request_was_aborted(transport, req)) {
 852		xs_close(xprt);
 853		return -ENOTCONN;
 854	}
 855
 856	xs_pktdump("packet data:",
 857			req->rq_svec->iov_base, req->rq_svec->iov_len);
 858
 859	req->rq_xtime = ktime_get();
 860	status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
 861				   transport->xmit.offset, rm, &sent);
 862	dprintk("RPC:       %s(%u) = %d\n",
 863			__func__, xdr->len - transport->xmit.offset, status);
 864
 865	if (status == -EAGAIN && sock_writeable(transport->inet))
 866		status = -ENOBUFS;
 867
 868	if (likely(sent > 0) || status == 0) {
 869		transport->xmit.offset += sent;
 870		req->rq_bytes_sent = transport->xmit.offset;
 871		if (likely(req->rq_bytes_sent >= msglen)) {
 872			req->rq_xmit_bytes_sent += transport->xmit.offset;
 873			transport->xmit.offset = 0;
 874			return 0;
 875		}
 876		status = -EAGAIN;
 877	}
 878
 879	switch (status) {
 880	case -ENOBUFS:
 881		break;
 882	case -EAGAIN:
 883		status = xs_nospace(req);
 884		break;
 885	default:
 886		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 887			-status);
 888		fallthrough;
 889	case -EPIPE:
 890		xs_close(xprt);
 891		status = -ENOTCONN;
 892	}
 893
 894	return status;
 895}
 896
 897/**
 898 * xs_udp_send_request - write an RPC request to a UDP socket
 899 * @req: pointer to RPC request
 900 *
 901 * Return values:
 902 *        0:	The request has been sent
 903 *   EAGAIN:	The socket was blocked, please call again later to
 904 *		complete the request
 905 * ENOTCONN:	Caller needs to invoke connect logic then call again
 906 *    other:	Some other error occurred, the request was not sent
 907 */
 908static int xs_udp_send_request(struct rpc_rqst *req)
 909{
 910	struct rpc_xprt *xprt = req->rq_xprt;
 911	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 912	struct xdr_buf *xdr = &req->rq_snd_buf;
 913	struct msghdr msg = {
 914		.msg_name	= xs_addr(xprt),
 915		.msg_namelen	= xprt->addrlen,
 916		.msg_flags	= XS_SENDMSG_FLAGS,
 917	};
 918	unsigned int sent;
 919	int status;
 920
 921	xs_pktdump("packet data:",
 922				req->rq_svec->iov_base,
 923				req->rq_svec->iov_len);
 924
 925	if (!xprt_bound(xprt))
 926		return -ENOTCONN;
 927
 928	if (!xprt_request_get_cong(xprt, req))
 929		return -EBADSLT;
 930
 931	req->rq_xtime = ktime_get();
 932	status = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, 0, &sent);
 
 933
 934	dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
 935			xdr->len, status);
 936
 937	/* firewall is blocking us, don't return -EAGAIN or we end up looping */
 938	if (status == -EPERM)
 939		goto process_status;
 940
 941	if (status == -EAGAIN && sock_writeable(transport->inet))
 942		status = -ENOBUFS;
 943
 944	if (sent > 0 || status == 0) {
 945		req->rq_xmit_bytes_sent += sent;
 946		if (sent >= req->rq_slen)
 947			return 0;
 948		/* Still some bytes left; set up for a retry later. */
 949		status = -EAGAIN;
 950	}
 951
 952process_status:
 953	switch (status) {
 954	case -ENOTSOCK:
 955		status = -ENOTCONN;
 956		/* Should we call xs_close() here? */
 957		break;
 958	case -EAGAIN:
 959		status = xs_nospace(req);
 960		break;
 961	case -ENETUNREACH:
 962	case -ENOBUFS:
 963	case -EPIPE:
 964	case -ECONNREFUSED:
 965	case -EPERM:
 966		/* When the server has died, an ICMP port unreachable message
 967		 * prompts ECONNREFUSED. */
 968		break;
 969	default:
 970		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 971			-status);
 972	}
 973
 974	return status;
 975}
 976
 977/**
 978 * xs_tcp_send_request - write an RPC request to a TCP socket
 979 * @req: pointer to RPC request
 980 *
 981 * Return values:
 982 *        0:	The request has been sent
 983 *   EAGAIN:	The socket was blocked, please call again later to
 984 *		complete the request
 985 * ENOTCONN:	Caller needs to invoke connect logic then call again
 986 *    other:	Some other error occurred, the request was not sent
 987 *
 988 * XXX: In the case of soft timeouts, should we eventually give up
 989 *	if sendmsg is not able to make progress?
 990 */
 991static int xs_tcp_send_request(struct rpc_rqst *req)
 992{
 993	struct rpc_xprt *xprt = req->rq_xprt;
 994	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 995	struct xdr_buf *xdr = &req->rq_snd_buf;
 996	rpc_fraghdr rm = xs_stream_record_marker(xdr);
 997	unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
 998	struct msghdr msg = {
 999		.msg_flags	= XS_SENDMSG_FLAGS,
1000	};
1001	bool vm_wait = false;
1002	unsigned int sent;
1003	int status;
 
1004
1005	/* Close the stream if the previous transmission was incomplete */
1006	if (xs_send_request_was_aborted(transport, req)) {
1007		if (transport->sock != NULL)
1008			kernel_sock_shutdown(transport->sock, SHUT_RDWR);
1009		return -ENOTCONN;
1010	}
1011
1012	xs_pktdump("packet data:",
1013				req->rq_svec->iov_base,
1014				req->rq_svec->iov_len);
1015
1016	if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state))
1017		xs_tcp_set_socket_timeouts(xprt, transport->sock);
1018
1019	/* Continue transmitting the packet/record. We must be careful
1020	 * to cope with writespace callbacks arriving _after_ we have
1021	 * called sendmsg(). */
1022	req->rq_xtime = ktime_get();
1023	while (1) {
1024		status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
1025					   transport->xmit.offset, rm, &sent);
 
1026
1027		dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
1028				xdr->len - transport->xmit.offset, status);
1029
1030		/* If we've sent the entire packet, immediately
1031		 * reset the count of bytes sent. */
1032		transport->xmit.offset += sent;
1033		req->rq_bytes_sent = transport->xmit.offset;
1034		if (likely(req->rq_bytes_sent >= msglen)) {
1035			req->rq_xmit_bytes_sent += transport->xmit.offset;
1036			transport->xmit.offset = 0;
1037			return 0;
1038		}
1039
1040		WARN_ON_ONCE(sent == 0 && status == 0);
1041
1042		if (status == -EAGAIN ) {
1043			/*
1044			 * Return EAGAIN if we're sure we're hitting the
1045			 * socket send buffer limits.
1046			 */
1047			if (test_bit(SOCK_NOSPACE, &transport->sock->flags))
1048				break;
1049			/*
1050			 * Did we hit a memory allocation failure?
1051			 */
1052			if (sent == 0) {
1053				status = -ENOBUFS;
1054				if (vm_wait)
1055					break;
1056				/* Retry, knowing now that we're below the
1057				 * socket send buffer limit
1058				 */
1059				vm_wait = true;
1060			}
1061			continue;
1062		}
1063		if (status < 0)
1064			break;
1065		vm_wait = false;
1066	}
1067
1068	switch (status) {
1069	case -ENOTSOCK:
1070		status = -ENOTCONN;
1071		/* Should we call xs_close() here? */
1072		break;
1073	case -EAGAIN:
1074		status = xs_nospace(req);
1075		break;
1076	case -ECONNRESET:
1077	case -ECONNREFUSED:
1078	case -ENOTCONN:
1079	case -EADDRINUSE:
1080	case -ENOBUFS:
1081	case -EPIPE:
1082		break;
1083	default:
1084		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1085			-status);
1086	}
1087
1088	return status;
1089}
1090
1091static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1092{
1093	transport->old_data_ready = sk->sk_data_ready;
1094	transport->old_state_change = sk->sk_state_change;
1095	transport->old_write_space = sk->sk_write_space;
1096	transport->old_error_report = sk->sk_error_report;
1097}
1098
1099static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1100{
1101	sk->sk_data_ready = transport->old_data_ready;
1102	sk->sk_state_change = transport->old_state_change;
1103	sk->sk_write_space = transport->old_write_space;
1104	sk->sk_error_report = transport->old_error_report;
1105}
1106
1107static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
1108{
1109	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1110
1111	clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1112	clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state);
1113	clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state);
1114	clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state);
1115}
1116
1117static void xs_run_error_worker(struct sock_xprt *transport, unsigned int nr)
1118{
1119	set_bit(nr, &transport->sock_state);
1120	queue_work(xprtiod_workqueue, &transport->error_worker);
1121}
1122
1123static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
1124{
1125	smp_mb__before_atomic();
1126	clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1127	clear_bit(XPRT_CLOSING, &xprt->state);
1128	xs_sock_reset_state_flags(xprt);
1129	smp_mb__after_atomic();
1130}
1131
1132/**
1133 * xs_error_report - callback to handle TCP socket state errors
1134 * @sk: socket
1135 *
1136 * Note: we don't call sock_error() since there may be a rpc_task
1137 * using the socket, and so we don't want to clear sk->sk_err.
1138 */
1139static void xs_error_report(struct sock *sk)
1140{
1141	struct sock_xprt *transport;
1142	struct rpc_xprt *xprt;
1143
1144	read_lock_bh(&sk->sk_callback_lock);
1145	if (!(xprt = xprt_from_sock(sk)))
1146		goto out;
1147
1148	transport = container_of(xprt, struct sock_xprt, xprt);
1149	transport->xprt_err = -sk->sk_err;
1150	if (transport->xprt_err == 0)
1151		goto out;
1152	dprintk("RPC:       xs_error_report client %p, error=%d...\n",
1153			xprt, -transport->xprt_err);
1154	trace_rpc_socket_error(xprt, sk->sk_socket, transport->xprt_err);
1155
1156	/* barrier ensures xprt_err is set before XPRT_SOCK_WAKE_ERROR */
1157	smp_mb__before_atomic();
1158	xs_run_error_worker(transport, XPRT_SOCK_WAKE_ERROR);
1159 out:
1160	read_unlock_bh(&sk->sk_callback_lock);
1161}
1162
1163static void xs_reset_transport(struct sock_xprt *transport)
1164{
1165	struct socket *sock = transport->sock;
1166	struct sock *sk = transport->inet;
1167	struct rpc_xprt *xprt = &transport->xprt;
1168	struct file *filp = transport->file;
1169
1170	if (sk == NULL)
1171		return;
1172
1173	if (atomic_read(&transport->xprt.swapper))
1174		sk_clear_memalloc(sk);
1175
1176	kernel_sock_shutdown(sock, SHUT_RDWR);
1177
1178	mutex_lock(&transport->recv_mutex);
1179	write_lock_bh(&sk->sk_callback_lock);
1180	transport->inet = NULL;
1181	transport->sock = NULL;
1182	transport->file = NULL;
1183
1184	sk->sk_user_data = NULL;
1185
1186	xs_restore_old_callbacks(transport, sk);
1187	xprt_clear_connected(xprt);
1188	write_unlock_bh(&sk->sk_callback_lock);
1189	xs_sock_reset_connection_flags(xprt);
1190	/* Reset stream record info */
1191	xs_stream_reset_connect(transport);
1192	mutex_unlock(&transport->recv_mutex);
1193
1194	trace_rpc_socket_close(xprt, sock);
1195	fput(filp);
1196
1197	xprt_disconnect_done(xprt);
1198}
1199
1200/**
1201 * xs_close - close a socket
1202 * @xprt: transport
1203 *
1204 * This is used when all requests are complete; ie, no DRC state remains
1205 * on the server we want to save.
1206 *
1207 * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
1208 * xs_reset_transport() zeroing the socket from underneath a writer.
1209 */
1210static void xs_close(struct rpc_xprt *xprt)
1211{
1212	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1213
1214	dprintk("RPC:       xs_close xprt %p\n", xprt);
1215
1216	xs_reset_transport(transport);
1217	xprt->reestablish_timeout = 0;
1218}
1219
1220static void xs_inject_disconnect(struct rpc_xprt *xprt)
1221{
1222	dprintk("RPC:       injecting transport disconnect on xprt=%p\n",
1223		xprt);
1224	xprt_disconnect_done(xprt);
1225}
1226
1227static void xs_xprt_free(struct rpc_xprt *xprt)
1228{
1229	xs_free_peer_addresses(xprt);
1230	xprt_free(xprt);
1231}
1232
1233/**
1234 * xs_destroy - prepare to shutdown a transport
1235 * @xprt: doomed transport
1236 *
1237 */
1238static void xs_destroy(struct rpc_xprt *xprt)
1239{
1240	struct sock_xprt *transport = container_of(xprt,
1241			struct sock_xprt, xprt);
1242	dprintk("RPC:       xs_destroy xprt %p\n", xprt);
1243
1244	cancel_delayed_work_sync(&transport->connect_worker);
1245	xs_close(xprt);
1246	cancel_work_sync(&transport->recv_worker);
1247	cancel_work_sync(&transport->error_worker);
1248	xs_xprt_free(xprt);
1249	module_put(THIS_MODULE);
1250}
1251
1252/**
1253 * xs_udp_data_read_skb - receive callback for UDP sockets
1254 * @xprt: transport
1255 * @sk: socket
1256 * @skb: skbuff
1257 *
1258 */
1259static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
1260		struct sock *sk,
1261		struct sk_buff *skb)
1262{
1263	struct rpc_task *task;
1264	struct rpc_rqst *rovr;
1265	int repsize, copied;
1266	u32 _xid;
1267	__be32 *xp;
1268
1269	repsize = skb->len;
1270	if (repsize < 4) {
1271		dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
1272		return;
1273	}
1274
1275	/* Copy the XID from the skb... */
1276	xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
1277	if (xp == NULL)
1278		return;
1279
1280	/* Look up and lock the request corresponding to the given XID */
1281	spin_lock(&xprt->queue_lock);
1282	rovr = xprt_lookup_rqst(xprt, *xp);
1283	if (!rovr)
1284		goto out_unlock;
1285	xprt_pin_rqst(rovr);
1286	xprt_update_rtt(rovr->rq_task);
1287	spin_unlock(&xprt->queue_lock);
1288	task = rovr->rq_task;
1289
1290	if ((copied = rovr->rq_private_buf.buflen) > repsize)
1291		copied = repsize;
1292
1293	/* Suck it into the iovec, verify checksum if not done by hw. */
1294	if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1295		spin_lock(&xprt->queue_lock);
1296		__UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
1297		goto out_unpin;
1298	}
1299
1300
1301	spin_lock(&xprt->transport_lock);
1302	xprt_adjust_cwnd(xprt, task, copied);
1303	spin_unlock(&xprt->transport_lock);
1304	spin_lock(&xprt->queue_lock);
1305	xprt_complete_rqst(task, copied);
1306	__UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
1307out_unpin:
1308	xprt_unpin_rqst(rovr);
1309 out_unlock:
1310	spin_unlock(&xprt->queue_lock);
1311}
1312
1313static void xs_udp_data_receive(struct sock_xprt *transport)
1314{
1315	struct sk_buff *skb;
1316	struct sock *sk;
1317	int err;
1318
1319	mutex_lock(&transport->recv_mutex);
1320	sk = transport->inet;
1321	if (sk == NULL)
1322		goto out;
1323	for (;;) {
1324		skb = skb_recv_udp(sk, 0, 1, &err);
1325		if (skb == NULL)
1326			break;
1327		xs_udp_data_read_skb(&transport->xprt, sk, skb);
1328		consume_skb(skb);
1329		cond_resched();
1330	}
1331	xs_poll_check_readable(transport);
1332out:
1333	mutex_unlock(&transport->recv_mutex);
1334}
1335
1336static void xs_udp_data_receive_workfn(struct work_struct *work)
1337{
1338	struct sock_xprt *transport =
1339		container_of(work, struct sock_xprt, recv_worker);
1340	unsigned int pflags = memalloc_nofs_save();
1341
1342	xs_udp_data_receive(transport);
1343	memalloc_nofs_restore(pflags);
1344}
1345
1346/**
1347 * xs_data_ready - "data ready" callback for UDP sockets
1348 * @sk: socket with data to read
1349 *
1350 */
1351static void xs_data_ready(struct sock *sk)
1352{
1353	struct rpc_xprt *xprt;
1354
1355	read_lock_bh(&sk->sk_callback_lock);
1356	dprintk("RPC:       xs_data_ready...\n");
1357	xprt = xprt_from_sock(sk);
1358	if (xprt != NULL) {
1359		struct sock_xprt *transport = container_of(xprt,
1360				struct sock_xprt, xprt);
1361		transport->old_data_ready(sk);
1362		/* Any data means we had a useful conversation, so
1363		 * then we don't need to delay the next reconnect
1364		 */
1365		if (xprt->reestablish_timeout)
1366			xprt->reestablish_timeout = 0;
1367		if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1368			queue_work(xprtiod_workqueue, &transport->recv_worker);
1369	}
1370	read_unlock_bh(&sk->sk_callback_lock);
1371}
1372
1373/*
1374 * Helper function to force a TCP close if the server is sending
1375 * junk and/or it has put us in CLOSE_WAIT
1376 */
1377static void xs_tcp_force_close(struct rpc_xprt *xprt)
1378{
1379	xprt_force_disconnect(xprt);
1380}
1381
1382#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1383static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
1384{
1385	return PAGE_SIZE;
1386}
1387#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1388
1389/**
1390 * xs_tcp_state_change - callback to handle TCP socket state changes
1391 * @sk: socket whose state has changed
1392 *
1393 */
1394static void xs_tcp_state_change(struct sock *sk)
1395{
1396	struct rpc_xprt *xprt;
1397	struct sock_xprt *transport;
1398
1399	read_lock_bh(&sk->sk_callback_lock);
1400	if (!(xprt = xprt_from_sock(sk)))
1401		goto out;
1402	dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1403	dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1404			sk->sk_state, xprt_connected(xprt),
1405			sock_flag(sk, SOCK_DEAD),
1406			sock_flag(sk, SOCK_ZAPPED),
1407			sk->sk_shutdown);
1408
1409	transport = container_of(xprt, struct sock_xprt, xprt);
1410	trace_rpc_socket_state_change(xprt, sk->sk_socket);
1411	switch (sk->sk_state) {
1412	case TCP_ESTABLISHED:
1413		if (!xprt_test_and_set_connected(xprt)) {
1414			xprt->connect_cookie++;
1415			clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
1416			xprt_clear_connecting(xprt);
1417
1418			xprt->stat.connect_count++;
1419			xprt->stat.connect_time += (long)jiffies -
1420						   xprt->stat.connect_start;
1421			xs_run_error_worker(transport, XPRT_SOCK_WAKE_PENDING);
1422		}
1423		break;
1424	case TCP_FIN_WAIT1:
1425		/* The client initiated a shutdown of the socket */
1426		xprt->connect_cookie++;
1427		xprt->reestablish_timeout = 0;
1428		set_bit(XPRT_CLOSING, &xprt->state);
1429		smp_mb__before_atomic();
1430		clear_bit(XPRT_CONNECTED, &xprt->state);
1431		clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1432		smp_mb__after_atomic();
1433		break;
1434	case TCP_CLOSE_WAIT:
1435		/* The server initiated a shutdown of the socket */
1436		xprt->connect_cookie++;
1437		clear_bit(XPRT_CONNECTED, &xprt->state);
1438		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1439		fallthrough;
1440	case TCP_CLOSING:
1441		/*
1442		 * If the server closed down the connection, make sure that
1443		 * we back off before reconnecting
1444		 */
1445		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1446			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1447		break;
1448	case TCP_LAST_ACK:
1449		set_bit(XPRT_CLOSING, &xprt->state);
1450		smp_mb__before_atomic();
1451		clear_bit(XPRT_CONNECTED, &xprt->state);
1452		smp_mb__after_atomic();
1453		break;
1454	case TCP_CLOSE:
1455		if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
1456					&transport->sock_state))
1457			xprt_clear_connecting(xprt);
1458		clear_bit(XPRT_CLOSING, &xprt->state);
1459		/* Trigger the socket release */
1460		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1461	}
1462 out:
1463	read_unlock_bh(&sk->sk_callback_lock);
1464}
1465
1466static void xs_write_space(struct sock *sk)
1467{
1468	struct socket_wq *wq;
1469	struct sock_xprt *transport;
1470	struct rpc_xprt *xprt;
1471
1472	if (!sk->sk_socket)
1473		return;
1474	clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1475
1476	if (unlikely(!(xprt = xprt_from_sock(sk))))
1477		return;
1478	transport = container_of(xprt, struct sock_xprt, xprt);
1479	rcu_read_lock();
1480	wq = rcu_dereference(sk->sk_wq);
1481	if (!wq || test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags) == 0)
1482		goto out;
1483
1484	xs_run_error_worker(transport, XPRT_SOCK_WAKE_WRITE);
1485	sk->sk_write_pending--;
1486out:
1487	rcu_read_unlock();
1488}
1489
1490/**
1491 * xs_udp_write_space - callback invoked when socket buffer space
1492 *                             becomes available
1493 * @sk: socket whose state has changed
1494 *
1495 * Called when more output buffer space is available for this socket.
1496 * We try not to wake our writers until they can make "significant"
1497 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1498 * with a bunch of small requests.
1499 */
1500static void xs_udp_write_space(struct sock *sk)
1501{
1502	read_lock_bh(&sk->sk_callback_lock);
1503
1504	/* from net/core/sock.c:sock_def_write_space */
1505	if (sock_writeable(sk))
1506		xs_write_space(sk);
1507
1508	read_unlock_bh(&sk->sk_callback_lock);
1509}
1510
1511/**
1512 * xs_tcp_write_space - callback invoked when socket buffer space
1513 *                             becomes available
1514 * @sk: socket whose state has changed
1515 *
1516 * Called when more output buffer space is available for this socket.
1517 * We try not to wake our writers until they can make "significant"
1518 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1519 * with a bunch of small requests.
1520 */
1521static void xs_tcp_write_space(struct sock *sk)
1522{
1523	read_lock_bh(&sk->sk_callback_lock);
1524
1525	/* from net/core/stream.c:sk_stream_write_space */
1526	if (sk_stream_is_writeable(sk))
1527		xs_write_space(sk);
1528
1529	read_unlock_bh(&sk->sk_callback_lock);
1530}
1531
1532static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1533{
1534	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1535	struct sock *sk = transport->inet;
1536
1537	if (transport->rcvsize) {
1538		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1539		sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1540	}
1541	if (transport->sndsize) {
1542		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1543		sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1544		sk->sk_write_space(sk);
1545	}
1546}
1547
1548/**
1549 * xs_udp_set_buffer_size - set send and receive limits
1550 * @xprt: generic transport
1551 * @sndsize: requested size of send buffer, in bytes
1552 * @rcvsize: requested size of receive buffer, in bytes
1553 *
1554 * Set socket send and receive buffer size limits.
1555 */
1556static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1557{
1558	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1559
1560	transport->sndsize = 0;
1561	if (sndsize)
1562		transport->sndsize = sndsize + 1024;
1563	transport->rcvsize = 0;
1564	if (rcvsize)
1565		transport->rcvsize = rcvsize + 1024;
1566
1567	xs_udp_do_set_buffer_size(xprt);
1568}
1569
1570/**
1571 * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1572 * @xprt: controlling transport
1573 * @task: task that timed out
1574 *
1575 * Adjust the congestion window after a retransmit timeout has occurred.
1576 */
1577static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1578{
1579	spin_lock(&xprt->transport_lock);
1580	xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1581	spin_unlock(&xprt->transport_lock);
1582}
1583
1584static int xs_get_random_port(void)
1585{
1586	unsigned short min = xprt_min_resvport, max = xprt_max_resvport;
1587	unsigned short range;
1588	unsigned short rand;
1589
1590	if (max < min)
1591		return -EADDRINUSE;
1592	range = max - min + 1;
1593	rand = (unsigned short) prandom_u32() % range;
1594	return rand + min;
1595}
1596
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1597static unsigned short xs_sock_getport(struct socket *sock)
1598{
1599	struct sockaddr_storage buf;
1600	unsigned short port = 0;
1601
1602	if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0)
1603		goto out;
1604	switch (buf.ss_family) {
1605	case AF_INET6:
1606		port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1607		break;
1608	case AF_INET:
1609		port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1610	}
1611out:
1612	return port;
1613}
1614
1615/**
1616 * xs_set_port - reset the port number in the remote endpoint address
1617 * @xprt: generic transport
1618 * @port: new port number
1619 *
1620 */
1621static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1622{
1623	dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1624
1625	rpc_set_port(xs_addr(xprt), port);
1626	xs_update_peer_port(xprt);
1627}
1628
1629static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1630{
1631	if (transport->srcport == 0 && transport->xprt.reuseport)
1632		transport->srcport = xs_sock_getport(sock);
1633}
1634
1635static int xs_get_srcport(struct sock_xprt *transport)
1636{
1637	int port = transport->srcport;
1638
1639	if (port == 0 && transport->xprt.resvport)
1640		port = xs_get_random_port();
1641	return port;
1642}
1643
1644static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1645{
1646	if (transport->srcport != 0)
1647		transport->srcport = 0;
1648	if (!transport->xprt.resvport)
1649		return 0;
1650	if (port <= xprt_min_resvport || port > xprt_max_resvport)
1651		return xprt_max_resvport;
1652	return --port;
1653}
1654static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1655{
1656	struct sockaddr_storage myaddr;
1657	int err, nloop = 0;
1658	int port = xs_get_srcport(transport);
1659	unsigned short last;
1660
1661	/*
1662	 * If we are asking for any ephemeral port (i.e. port == 0 &&
1663	 * transport->xprt.resvport == 0), don't bind.  Let the local
1664	 * port selection happen implicitly when the socket is used
1665	 * (for example at connect time).
1666	 *
1667	 * This ensures that we can continue to establish TCP
1668	 * connections even when all local ephemeral ports are already
1669	 * a part of some TCP connection.  This makes no difference
1670	 * for UDP sockets, but also doens't harm them.
1671	 *
1672	 * If we're asking for any reserved port (i.e. port == 0 &&
1673	 * transport->xprt.resvport == 1) xs_get_srcport above will
1674	 * ensure that port is non-zero and we will bind as needed.
1675	 */
1676	if (port <= 0)
1677		return port;
1678
1679	memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1680	do {
1681		rpc_set_port((struct sockaddr *)&myaddr, port);
1682		err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1683				transport->xprt.addrlen);
1684		if (err == 0) {
1685			transport->srcport = port;
1686			break;
1687		}
1688		last = port;
1689		port = xs_next_srcport(transport, port);
1690		if (port > last)
1691			nloop++;
1692	} while (err == -EADDRINUSE && nloop != 2);
1693
1694	if (myaddr.ss_family == AF_INET)
1695		dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1696				&((struct sockaddr_in *)&myaddr)->sin_addr,
1697				port, err ? "failed" : "ok", err);
1698	else
1699		dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1700				&((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1701				port, err ? "failed" : "ok", err);
1702	return err;
1703}
1704
1705/*
1706 * We don't support autobind on AF_LOCAL sockets
1707 */
1708static void xs_local_rpcbind(struct rpc_task *task)
1709{
1710	xprt_set_bound(task->tk_xprt);
1711}
1712
1713static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1714{
1715}
1716
1717#ifdef CONFIG_DEBUG_LOCK_ALLOC
1718static struct lock_class_key xs_key[2];
1719static struct lock_class_key xs_slock_key[2];
1720
1721static inline void xs_reclassify_socketu(struct socket *sock)
1722{
1723	struct sock *sk = sock->sk;
1724
1725	sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1726		&xs_slock_key[1], "sk_lock-AF_LOCAL-RPC", &xs_key[1]);
1727}
1728
1729static inline void xs_reclassify_socket4(struct socket *sock)
1730{
1731	struct sock *sk = sock->sk;
1732
1733	sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1734		&xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1735}
1736
1737static inline void xs_reclassify_socket6(struct socket *sock)
1738{
1739	struct sock *sk = sock->sk;
1740
1741	sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1742		&xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1743}
1744
1745static inline void xs_reclassify_socket(int family, struct socket *sock)
1746{
1747	if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
1748		return;
1749
1750	switch (family) {
1751	case AF_LOCAL:
1752		xs_reclassify_socketu(sock);
1753		break;
1754	case AF_INET:
1755		xs_reclassify_socket4(sock);
1756		break;
1757	case AF_INET6:
1758		xs_reclassify_socket6(sock);
1759		break;
1760	}
1761}
1762#else
1763static inline void xs_reclassify_socket(int family, struct socket *sock)
1764{
1765}
1766#endif
1767
1768static void xs_dummy_setup_socket(struct work_struct *work)
1769{
1770}
1771
1772static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1773		struct sock_xprt *transport, int family, int type,
1774		int protocol, bool reuseport)
1775{
1776	struct file *filp;
1777	struct socket *sock;
1778	int err;
1779
1780	err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1781	if (err < 0) {
1782		dprintk("RPC:       can't create %d transport socket (%d).\n",
1783				protocol, -err);
1784		goto out;
1785	}
1786	xs_reclassify_socket(family, sock);
1787
1788	if (reuseport)
1789		sock_set_reuseport(sock->sk);
1790
1791	err = xs_bind(transport, sock);
1792	if (err) {
1793		sock_release(sock);
1794		goto out;
1795	}
1796
1797	filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1798	if (IS_ERR(filp))
1799		return ERR_CAST(filp);
1800	transport->file = filp;
1801
1802	return sock;
1803out:
1804	return ERR_PTR(err);
1805}
1806
1807static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1808				      struct socket *sock)
1809{
1810	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1811									xprt);
1812
1813	if (!transport->inet) {
1814		struct sock *sk = sock->sk;
1815
1816		write_lock_bh(&sk->sk_callback_lock);
1817
1818		xs_save_old_callbacks(transport, sk);
1819
1820		sk->sk_user_data = xprt;
1821		sk->sk_data_ready = xs_data_ready;
1822		sk->sk_write_space = xs_udp_write_space;
1823		sock_set_flag(sk, SOCK_FASYNC);
1824		sk->sk_error_report = xs_error_report;
1825
1826		xprt_clear_connected(xprt);
1827
1828		/* Reset to new socket */
1829		transport->sock = sock;
1830		transport->inet = sk;
1831
1832		write_unlock_bh(&sk->sk_callback_lock);
1833	}
1834
1835	xs_stream_start_connect(transport);
1836
1837	return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1838}
1839
1840/**
1841 * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1842 * @transport: socket transport to connect
1843 */
1844static int xs_local_setup_socket(struct sock_xprt *transport)
1845{
1846	struct rpc_xprt *xprt = &transport->xprt;
1847	struct file *filp;
1848	struct socket *sock;
1849	int status;
1850
1851	status = __sock_create(xprt->xprt_net, AF_LOCAL,
1852					SOCK_STREAM, 0, &sock, 1);
1853	if (status < 0) {
1854		dprintk("RPC:       can't create AF_LOCAL "
1855			"transport socket (%d).\n", -status);
1856		goto out;
1857	}
1858	xs_reclassify_socket(AF_LOCAL, sock);
1859
1860	filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1861	if (IS_ERR(filp)) {
1862		status = PTR_ERR(filp);
1863		goto out;
1864	}
1865	transport->file = filp;
1866
1867	dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
1868			xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1869
1870	status = xs_local_finish_connecting(xprt, sock);
1871	trace_rpc_socket_connect(xprt, sock, status);
1872	switch (status) {
1873	case 0:
1874		dprintk("RPC:       xprt %p connected to %s\n",
1875				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1876		xprt->stat.connect_count++;
1877		xprt->stat.connect_time += (long)jiffies -
1878					   xprt->stat.connect_start;
1879		xprt_set_connected(xprt);
1880	case -ENOBUFS:
1881		break;
1882	case -ENOENT:
1883		dprintk("RPC:       xprt %p: socket %s does not exist\n",
1884				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1885		break;
1886	case -ECONNREFUSED:
1887		dprintk("RPC:       xprt %p: connection refused for %s\n",
1888				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1889		break;
1890	default:
1891		printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
1892				__func__, -status,
1893				xprt->address_strings[RPC_DISPLAY_ADDR]);
1894	}
1895
1896out:
1897	xprt_clear_connecting(xprt);
1898	xprt_wake_pending_tasks(xprt, status);
1899	return status;
1900}
1901
1902static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
1903{
1904	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1905	int ret;
1906
1907	 if (RPC_IS_ASYNC(task)) {
1908		/*
1909		 * We want the AF_LOCAL connect to be resolved in the
1910		 * filesystem namespace of the process making the rpc
1911		 * call.  Thus we connect synchronously.
1912		 *
1913		 * If we want to support asynchronous AF_LOCAL calls,
1914		 * we'll need to figure out how to pass a namespace to
1915		 * connect.
1916		 */
1917		task->tk_rpc_status = -ENOTCONN;
1918		rpc_exit(task, -ENOTCONN);
1919		return;
1920	}
1921	ret = xs_local_setup_socket(transport);
1922	if (ret && !RPC_IS_SOFTCONN(task))
1923		msleep_interruptible(15000);
1924}
1925
1926#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
1927/*
1928 * Note that this should be called with XPRT_LOCKED held (or when we otherwise
1929 * know that we have exclusive access to the socket), to guard against
1930 * races with xs_reset_transport.
1931 */
1932static void xs_set_memalloc(struct rpc_xprt *xprt)
1933{
1934	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1935			xprt);
1936
1937	/*
1938	 * If there's no sock, then we have nothing to set. The
1939	 * reconnecting process will get it for us.
1940	 */
1941	if (!transport->inet)
1942		return;
1943	if (atomic_read(&xprt->swapper))
1944		sk_set_memalloc(transport->inet);
1945}
1946
1947/**
1948 * xs_enable_swap - Tag this transport as being used for swap.
1949 * @xprt: transport to tag
1950 *
1951 * Take a reference to this transport on behalf of the rpc_clnt, and
1952 * optionally mark it for swapping if it wasn't already.
1953 */
1954static int
1955xs_enable_swap(struct rpc_xprt *xprt)
1956{
1957	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
1958
1959	if (atomic_inc_return(&xprt->swapper) != 1)
1960		return 0;
1961	if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
1962		return -ERESTARTSYS;
1963	if (xs->inet)
1964		sk_set_memalloc(xs->inet);
1965	xprt_release_xprt(xprt, NULL);
1966	return 0;
1967}
1968
1969/**
1970 * xs_disable_swap - Untag this transport as being used for swap.
1971 * @xprt: transport to tag
1972 *
1973 * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
1974 * swapper refcount goes to 0, untag the socket as a memalloc socket.
1975 */
1976static void
1977xs_disable_swap(struct rpc_xprt *xprt)
1978{
1979	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
1980
1981	if (!atomic_dec_and_test(&xprt->swapper))
1982		return;
1983	if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
1984		return;
1985	if (xs->inet)
1986		sk_clear_memalloc(xs->inet);
1987	xprt_release_xprt(xprt, NULL);
1988}
1989#else
1990static void xs_set_memalloc(struct rpc_xprt *xprt)
1991{
1992}
1993
1994static int
1995xs_enable_swap(struct rpc_xprt *xprt)
1996{
1997	return -EINVAL;
1998}
1999
2000static void
2001xs_disable_swap(struct rpc_xprt *xprt)
2002{
2003}
2004#endif
2005
2006static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2007{
2008	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2009
2010	if (!transport->inet) {
2011		struct sock *sk = sock->sk;
2012
2013		write_lock_bh(&sk->sk_callback_lock);
2014
2015		xs_save_old_callbacks(transport, sk);
2016
2017		sk->sk_user_data = xprt;
2018		sk->sk_data_ready = xs_data_ready;
2019		sk->sk_write_space = xs_udp_write_space;
2020		sock_set_flag(sk, SOCK_FASYNC);
2021
2022		xprt_set_connected(xprt);
2023
2024		/* Reset to new socket */
2025		transport->sock = sock;
2026		transport->inet = sk;
2027
2028		xs_set_memalloc(xprt);
2029
2030		write_unlock_bh(&sk->sk_callback_lock);
2031	}
2032	xs_udp_do_set_buffer_size(xprt);
2033
2034	xprt->stat.connect_start = jiffies;
2035}
2036
2037static void xs_udp_setup_socket(struct work_struct *work)
2038{
2039	struct sock_xprt *transport =
2040		container_of(work, struct sock_xprt, connect_worker.work);
2041	struct rpc_xprt *xprt = &transport->xprt;
2042	struct socket *sock;
2043	int status = -EIO;
2044
2045	sock = xs_create_sock(xprt, transport,
2046			xs_addr(xprt)->sa_family, SOCK_DGRAM,
2047			IPPROTO_UDP, false);
2048	if (IS_ERR(sock))
2049		goto out;
2050
2051	dprintk("RPC:       worker connecting xprt %p via %s to "
2052				"%s (port %s)\n", xprt,
2053			xprt->address_strings[RPC_DISPLAY_PROTO],
2054			xprt->address_strings[RPC_DISPLAY_ADDR],
2055			xprt->address_strings[RPC_DISPLAY_PORT]);
2056
2057	xs_udp_finish_connecting(xprt, sock);
2058	trace_rpc_socket_connect(xprt, sock, 0);
2059	status = 0;
2060out:
2061	xprt_clear_connecting(xprt);
2062	xprt_unlock_connect(xprt, transport);
2063	xprt_wake_pending_tasks(xprt, status);
2064}
2065
2066/**
2067 * xs_tcp_shutdown - gracefully shut down a TCP socket
2068 * @xprt: transport
2069 *
2070 * Initiates a graceful shutdown of the TCP socket by calling the
2071 * equivalent of shutdown(SHUT_RDWR);
2072 */
2073static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2074{
2075	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2076	struct socket *sock = transport->sock;
2077	int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
2078
2079	if (sock == NULL)
2080		return;
2081	switch (skst) {
2082	default:
2083		kernel_sock_shutdown(sock, SHUT_RDWR);
2084		trace_rpc_socket_shutdown(xprt, sock);
2085		break;
2086	case TCP_CLOSE:
2087	case TCP_TIME_WAIT:
2088		xs_reset_transport(transport);
2089	}
2090}
2091
2092static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
2093		struct socket *sock)
2094{
2095	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2096	unsigned int keepidle;
2097	unsigned int keepcnt;
 
2098	unsigned int timeo;
2099
2100	spin_lock(&xprt->transport_lock);
2101	keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
2102	keepcnt = xprt->timeout->to_retries + 1;
2103	timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2104		(xprt->timeout->to_retries + 1);
2105	clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2106	spin_unlock(&xprt->transport_lock);
2107
2108	/* TCP Keepalive options */
2109	sock_set_keepalive(sock->sk);
2110	tcp_sock_set_keepidle(sock->sk, keepidle);
2111	tcp_sock_set_keepintvl(sock->sk, keepidle);
2112	tcp_sock_set_keepcnt(sock->sk, keepcnt);
 
 
 
 
2113
2114	/* TCP user timeout (see RFC5482) */
2115	tcp_sock_set_user_timeout(sock->sk, timeo);
 
2116}
2117
2118static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
2119		unsigned long connect_timeout,
2120		unsigned long reconnect_timeout)
2121{
2122	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2123	struct rpc_timeout to;
2124	unsigned long initval;
2125
2126	spin_lock(&xprt->transport_lock);
2127	if (reconnect_timeout < xprt->max_reconnect_timeout)
2128		xprt->max_reconnect_timeout = reconnect_timeout;
2129	if (connect_timeout < xprt->connect_timeout) {
2130		memcpy(&to, xprt->timeout, sizeof(to));
2131		initval = DIV_ROUND_UP(connect_timeout, to.to_retries + 1);
2132		/* Arbitrary lower limit */
2133		if (initval <  XS_TCP_INIT_REEST_TO << 1)
2134			initval = XS_TCP_INIT_REEST_TO << 1;
2135		to.to_initval = initval;
2136		to.to_maxval = initval;
2137		memcpy(&transport->tcp_timeout, &to,
2138				sizeof(transport->tcp_timeout));
2139		xprt->timeout = &transport->tcp_timeout;
2140		xprt->connect_timeout = connect_timeout;
2141	}
2142	set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2143	spin_unlock(&xprt->transport_lock);
2144}
2145
2146static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2147{
2148	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2149	int ret = -ENOTCONN;
2150
2151	if (!transport->inet) {
2152		struct sock *sk = sock->sk;
 
2153
2154		/* Avoid temporary address, they are bad for long-lived
2155		 * connections such as NFS mounts.
2156		 * RFC4941, section 3.6 suggests that:
2157		 *    Individual applications, which have specific
2158		 *    knowledge about the normal duration of connections,
2159		 *    MAY override this as appropriate.
2160		 */
2161		if (xs_addr(xprt)->sa_family == PF_INET6) {
2162			ip6_sock_set_addr_preferences(sk,
2163				IPV6_PREFER_SRC_PUBLIC);
2164		}
2165
2166		xs_tcp_set_socket_timeouts(xprt, sock);
2167
2168		write_lock_bh(&sk->sk_callback_lock);
2169
2170		xs_save_old_callbacks(transport, sk);
2171
2172		sk->sk_user_data = xprt;
2173		sk->sk_data_ready = xs_data_ready;
2174		sk->sk_state_change = xs_tcp_state_change;
2175		sk->sk_write_space = xs_tcp_write_space;
2176		sock_set_flag(sk, SOCK_FASYNC);
2177		sk->sk_error_report = xs_error_report;
2178
2179		/* socket options */
2180		sock_reset_flag(sk, SOCK_LINGER);
2181		tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
2182
2183		xprt_clear_connected(xprt);
2184
2185		/* Reset to new socket */
2186		transport->sock = sock;
2187		transport->inet = sk;
2188
2189		write_unlock_bh(&sk->sk_callback_lock);
2190	}
2191
2192	if (!xprt_bound(xprt))
2193		goto out;
2194
2195	xs_set_memalloc(xprt);
2196
2197	xs_stream_start_connect(transport);
2198
2199	/* Tell the socket layer to start connecting... */
2200	set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2201	ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2202	switch (ret) {
2203	case 0:
2204		xs_set_srcport(transport, sock);
2205		fallthrough;
2206	case -EINPROGRESS:
2207		/* SYN_SENT! */
2208		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2209			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2210		break;
2211	case -EADDRNOTAVAIL:
2212		/* Source port number is unavailable. Try a new one! */
2213		transport->srcport = 0;
2214	}
2215out:
2216	return ret;
2217}
2218
2219/**
2220 * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2221 * @work: queued work item
2222 *
2223 * Invoked by a work queue tasklet.
2224 */
2225static void xs_tcp_setup_socket(struct work_struct *work)
2226{
2227	struct sock_xprt *transport =
2228		container_of(work, struct sock_xprt, connect_worker.work);
2229	struct socket *sock = transport->sock;
2230	struct rpc_xprt *xprt = &transport->xprt;
2231	int status = -EIO;
2232
2233	if (!sock) {
2234		sock = xs_create_sock(xprt, transport,
2235				xs_addr(xprt)->sa_family, SOCK_STREAM,
2236				IPPROTO_TCP, true);
2237		if (IS_ERR(sock)) {
2238			status = PTR_ERR(sock);
2239			goto out;
2240		}
2241	}
2242
2243	dprintk("RPC:       worker connecting xprt %p via %s to "
2244				"%s (port %s)\n", xprt,
2245			xprt->address_strings[RPC_DISPLAY_PROTO],
2246			xprt->address_strings[RPC_DISPLAY_ADDR],
2247			xprt->address_strings[RPC_DISPLAY_PORT]);
2248
2249	status = xs_tcp_finish_connecting(xprt, sock);
2250	trace_rpc_socket_connect(xprt, sock, status);
2251	dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2252			xprt, -status, xprt_connected(xprt),
2253			sock->sk->sk_state);
2254	switch (status) {
2255	default:
2256		printk("%s: connect returned unhandled error %d\n",
2257			__func__, status);
2258		fallthrough;
2259	case -EADDRNOTAVAIL:
2260		/* We're probably in TIME_WAIT. Get rid of existing socket,
2261		 * and retry
2262		 */
2263		xs_tcp_force_close(xprt);
2264		break;
2265	case 0:
2266	case -EINPROGRESS:
2267	case -EALREADY:
2268		xprt_unlock_connect(xprt, transport);
2269		return;
2270	case -EINVAL:
2271		/* Happens, for instance, if the user specified a link
2272		 * local IPv6 address without a scope-id.
2273		 */
2274	case -ECONNREFUSED:
2275	case -ECONNRESET:
2276	case -ENETDOWN:
2277	case -ENETUNREACH:
2278	case -EHOSTUNREACH:
2279	case -EADDRINUSE:
2280	case -ENOBUFS:
2281		/*
2282		 * xs_tcp_force_close() wakes tasks with -EIO.
2283		 * We need to wake them first to ensure the
2284		 * correct error code.
2285		 */
2286		xprt_wake_pending_tasks(xprt, status);
2287		xs_tcp_force_close(xprt);
2288		goto out;
2289	}
2290	status = -EAGAIN;
2291out:
2292	xprt_clear_connecting(xprt);
2293	xprt_unlock_connect(xprt, transport);
2294	xprt_wake_pending_tasks(xprt, status);
2295}
2296
2297/**
2298 * xs_connect - connect a socket to a remote endpoint
2299 * @xprt: pointer to transport structure
2300 * @task: address of RPC task that manages state of connect request
2301 *
2302 * TCP: If the remote end dropped the connection, delay reconnecting.
2303 *
2304 * UDP socket connects are synchronous, but we use a work queue anyway
2305 * to guarantee that even unprivileged user processes can set up a
2306 * socket on a privileged port.
2307 *
2308 * If a UDP socket connect fails, the delay behavior here prevents
2309 * retry floods (hard mounts).
2310 */
2311static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2312{
2313	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2314	unsigned long delay = 0;
2315
2316	WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2317
2318	if (transport->sock != NULL) {
2319		dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2320				"seconds\n",
2321				xprt, xprt->reestablish_timeout / HZ);
2322
2323		/* Start by resetting any existing state */
2324		xs_reset_transport(transport);
2325
2326		delay = xprt_reconnect_delay(xprt);
2327		xprt_reconnect_backoff(xprt, XS_TCP_INIT_REEST_TO);
2328
2329	} else
2330		dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2331
2332	queue_delayed_work(xprtiod_workqueue,
2333			&transport->connect_worker,
2334			delay);
2335}
2336
2337static void xs_wake_disconnect(struct sock_xprt *transport)
2338{
2339	if (test_and_clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state))
2340		xs_tcp_force_close(&transport->xprt);
2341}
2342
2343static void xs_wake_write(struct sock_xprt *transport)
2344{
2345	if (test_and_clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state))
2346		xprt_write_space(&transport->xprt);
2347}
2348
2349static void xs_wake_error(struct sock_xprt *transport)
2350{
2351	int sockerr;
2352
2353	if (!test_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2354		return;
2355	mutex_lock(&transport->recv_mutex);
2356	if (transport->sock == NULL)
2357		goto out;
2358	if (!test_and_clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2359		goto out;
2360	sockerr = xchg(&transport->xprt_err, 0);
2361	if (sockerr < 0)
2362		xprt_wake_pending_tasks(&transport->xprt, sockerr);
2363out:
2364	mutex_unlock(&transport->recv_mutex);
2365}
2366
2367static void xs_wake_pending(struct sock_xprt *transport)
2368{
2369	if (test_and_clear_bit(XPRT_SOCK_WAKE_PENDING, &transport->sock_state))
2370		xprt_wake_pending_tasks(&transport->xprt, -EAGAIN);
2371}
2372
2373static void xs_error_handle(struct work_struct *work)
2374{
2375	struct sock_xprt *transport = container_of(work,
2376			struct sock_xprt, error_worker);
2377
2378	xs_wake_disconnect(transport);
2379	xs_wake_write(transport);
2380	xs_wake_error(transport);
2381	xs_wake_pending(transport);
2382}
2383
2384/**
2385 * xs_local_print_stats - display AF_LOCAL socket-specifc stats
2386 * @xprt: rpc_xprt struct containing statistics
2387 * @seq: output file
2388 *
2389 */
2390static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2391{
2392	long idle_time = 0;
2393
2394	if (xprt_connected(xprt))
2395		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2396
2397	seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2398			"%llu %llu %lu %llu %llu\n",
2399			xprt->stat.bind_count,
2400			xprt->stat.connect_count,
2401			xprt->stat.connect_time / HZ,
2402			idle_time,
2403			xprt->stat.sends,
2404			xprt->stat.recvs,
2405			xprt->stat.bad_xids,
2406			xprt->stat.req_u,
2407			xprt->stat.bklog_u,
2408			xprt->stat.max_slots,
2409			xprt->stat.sending_u,
2410			xprt->stat.pending_u);
2411}
2412
2413/**
2414 * xs_udp_print_stats - display UDP socket-specifc stats
2415 * @xprt: rpc_xprt struct containing statistics
2416 * @seq: output file
2417 *
2418 */
2419static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2420{
2421	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2422
2423	seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2424			"%lu %llu %llu\n",
2425			transport->srcport,
2426			xprt->stat.bind_count,
2427			xprt->stat.sends,
2428			xprt->stat.recvs,
2429			xprt->stat.bad_xids,
2430			xprt->stat.req_u,
2431			xprt->stat.bklog_u,
2432			xprt->stat.max_slots,
2433			xprt->stat.sending_u,
2434			xprt->stat.pending_u);
2435}
2436
2437/**
2438 * xs_tcp_print_stats - display TCP socket-specifc stats
2439 * @xprt: rpc_xprt struct containing statistics
2440 * @seq: output file
2441 *
2442 */
2443static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2444{
2445	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2446	long idle_time = 0;
2447
2448	if (xprt_connected(xprt))
2449		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2450
2451	seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2452			"%llu %llu %lu %llu %llu\n",
2453			transport->srcport,
2454			xprt->stat.bind_count,
2455			xprt->stat.connect_count,
2456			xprt->stat.connect_time / HZ,
2457			idle_time,
2458			xprt->stat.sends,
2459			xprt->stat.recvs,
2460			xprt->stat.bad_xids,
2461			xprt->stat.req_u,
2462			xprt->stat.bklog_u,
2463			xprt->stat.max_slots,
2464			xprt->stat.sending_u,
2465			xprt->stat.pending_u);
2466}
2467
2468/*
2469 * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2470 * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2471 * to use the server side send routines.
2472 */
2473static int bc_malloc(struct rpc_task *task)
2474{
2475	struct rpc_rqst *rqst = task->tk_rqstp;
2476	size_t size = rqst->rq_callsize;
2477	struct page *page;
2478	struct rpc_buffer *buf;
2479
2480	if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2481		WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2482			  size);
2483		return -EINVAL;
2484	}
2485
2486	page = alloc_page(GFP_KERNEL);
2487	if (!page)
2488		return -ENOMEM;
2489
2490	buf = page_address(page);
2491	buf->len = PAGE_SIZE;
2492
2493	rqst->rq_buffer = buf->data;
2494	rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2495	return 0;
2496}
2497
2498/*
2499 * Free the space allocated in the bc_alloc routine
2500 */
2501static void bc_free(struct rpc_task *task)
2502{
2503	void *buffer = task->tk_rqstp->rq_buffer;
2504	struct rpc_buffer *buf;
2505
2506	buf = container_of(buffer, struct rpc_buffer, data);
2507	free_page((unsigned long)buf);
2508}
2509
 
 
 
 
2510static int bc_sendto(struct rpc_rqst *req)
2511{
2512	struct xdr_buf *xdr = &req->rq_snd_buf;
 
2513	struct sock_xprt *transport =
2514			container_of(req->rq_xprt, struct sock_xprt, xprt);
 
 
 
2515	struct msghdr msg = {
2516		.msg_flags	= 0,
2517	};
2518	rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT |
2519					 (u32)xdr->len);
2520	unsigned int sent = 0;
2521	int err;
 
 
2522
2523	req->rq_xtime = ktime_get();
2524	err = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, marker, &sent);
2525	xdr_free_bvec(xdr);
2526	if (err < 0 || sent != (xdr->len + sizeof(marker)))
 
 
 
 
 
 
 
 
 
2527		return -EAGAIN;
2528	return sent;
2529}
2530
2531/**
2532 * bc_send_request - Send a backchannel Call on a TCP socket
2533 * @req: rpc_rqst containing Call message to be sent
2534 *
2535 * xpt_mutex ensures @rqstp's whole message is written to the socket
2536 * without interruption.
2537 *
2538 * Return values:
2539 *   %0 if the message was sent successfully
2540 *   %ENOTCONN if the message was not sent
2541 */
2542static int bc_send_request(struct rpc_rqst *req)
2543{
2544	struct svc_xprt	*xprt;
2545	int len;
2546
 
2547	/*
2548	 * Get the server socket associated with this callback xprt
2549	 */
2550	xprt = req->rq_xprt->bc_xprt;
2551
2552	/*
2553	 * Grab the mutex to serialize data as the connection is shared
2554	 * with the fore channel
2555	 */
2556	mutex_lock(&xprt->xpt_mutex);
2557	if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2558		len = -ENOTCONN;
2559	else
2560		len = bc_sendto(req);
2561	mutex_unlock(&xprt->xpt_mutex);
2562
2563	if (len > 0)
2564		len = 0;
2565
2566	return len;
2567}
2568
2569/*
2570 * The close routine. Since this is client initiated, we do nothing
2571 */
2572
2573static void bc_close(struct rpc_xprt *xprt)
2574{
2575	xprt_disconnect_done(xprt);
2576}
2577
2578/*
2579 * The xprt destroy routine. Again, because this connection is client
2580 * initiated, we do nothing
2581 */
2582
2583static void bc_destroy(struct rpc_xprt *xprt)
2584{
2585	dprintk("RPC:       bc_destroy xprt %p\n", xprt);
2586
2587	xs_xprt_free(xprt);
2588	module_put(THIS_MODULE);
2589}
2590
2591static const struct rpc_xprt_ops xs_local_ops = {
2592	.reserve_xprt		= xprt_reserve_xprt,
2593	.release_xprt		= xprt_release_xprt,
2594	.alloc_slot		= xprt_alloc_slot,
2595	.free_slot		= xprt_free_slot,
2596	.rpcbind		= xs_local_rpcbind,
2597	.set_port		= xs_local_set_port,
2598	.connect		= xs_local_connect,
2599	.buf_alloc		= rpc_malloc,
2600	.buf_free		= rpc_free,
2601	.prepare_request	= xs_stream_prepare_request,
2602	.send_request		= xs_local_send_request,
2603	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
2604	.close			= xs_close,
2605	.destroy		= xs_destroy,
2606	.print_stats		= xs_local_print_stats,
2607	.enable_swap		= xs_enable_swap,
2608	.disable_swap		= xs_disable_swap,
2609};
2610
2611static const struct rpc_xprt_ops xs_udp_ops = {
2612	.set_buffer_size	= xs_udp_set_buffer_size,
2613	.reserve_xprt		= xprt_reserve_xprt_cong,
2614	.release_xprt		= xprt_release_xprt_cong,
2615	.alloc_slot		= xprt_alloc_slot,
2616	.free_slot		= xprt_free_slot,
2617	.rpcbind		= rpcb_getport_async,
2618	.set_port		= xs_set_port,
2619	.connect		= xs_connect,
2620	.buf_alloc		= rpc_malloc,
2621	.buf_free		= rpc_free,
2622	.send_request		= xs_udp_send_request,
2623	.wait_for_reply_request	= xprt_wait_for_reply_request_rtt,
2624	.timer			= xs_udp_timer,
2625	.release_request	= xprt_release_rqst_cong,
2626	.close			= xs_close,
2627	.destroy		= xs_destroy,
2628	.print_stats		= xs_udp_print_stats,
2629	.enable_swap		= xs_enable_swap,
2630	.disable_swap		= xs_disable_swap,
2631	.inject_disconnect	= xs_inject_disconnect,
2632};
2633
2634static const struct rpc_xprt_ops xs_tcp_ops = {
2635	.reserve_xprt		= xprt_reserve_xprt,
2636	.release_xprt		= xprt_release_xprt,
2637	.alloc_slot		= xprt_alloc_slot,
2638	.free_slot		= xprt_free_slot,
2639	.rpcbind		= rpcb_getport_async,
2640	.set_port		= xs_set_port,
2641	.connect		= xs_connect,
2642	.buf_alloc		= rpc_malloc,
2643	.buf_free		= rpc_free,
2644	.prepare_request	= xs_stream_prepare_request,
2645	.send_request		= xs_tcp_send_request,
2646	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
2647	.close			= xs_tcp_shutdown,
2648	.destroy		= xs_destroy,
2649	.set_connect_timeout	= xs_tcp_set_connect_timeout,
2650	.print_stats		= xs_tcp_print_stats,
2651	.enable_swap		= xs_enable_swap,
2652	.disable_swap		= xs_disable_swap,
2653	.inject_disconnect	= xs_inject_disconnect,
2654#ifdef CONFIG_SUNRPC_BACKCHANNEL
2655	.bc_setup		= xprt_setup_bc,
2656	.bc_maxpayload		= xs_tcp_bc_maxpayload,
2657	.bc_num_slots		= xprt_bc_max_slots,
2658	.bc_free_rqst		= xprt_free_bc_rqst,
2659	.bc_destroy		= xprt_destroy_bc,
2660#endif
2661};
2662
2663/*
2664 * The rpc_xprt_ops for the server backchannel
2665 */
2666
2667static const struct rpc_xprt_ops bc_tcp_ops = {
2668	.reserve_xprt		= xprt_reserve_xprt,
2669	.release_xprt		= xprt_release_xprt,
2670	.alloc_slot		= xprt_alloc_slot,
2671	.free_slot		= xprt_free_slot,
2672	.buf_alloc		= bc_malloc,
2673	.buf_free		= bc_free,
2674	.send_request		= bc_send_request,
2675	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
2676	.close			= bc_close,
2677	.destroy		= bc_destroy,
2678	.print_stats		= xs_tcp_print_stats,
2679	.enable_swap		= xs_enable_swap,
2680	.disable_swap		= xs_disable_swap,
2681	.inject_disconnect	= xs_inject_disconnect,
2682};
2683
2684static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2685{
2686	static const struct sockaddr_in sin = {
2687		.sin_family		= AF_INET,
2688		.sin_addr.s_addr	= htonl(INADDR_ANY),
2689	};
2690	static const struct sockaddr_in6 sin6 = {
2691		.sin6_family		= AF_INET6,
2692		.sin6_addr		= IN6ADDR_ANY_INIT,
2693	};
2694
2695	switch (family) {
2696	case AF_LOCAL:
2697		break;
2698	case AF_INET:
2699		memcpy(sap, &sin, sizeof(sin));
2700		break;
2701	case AF_INET6:
2702		memcpy(sap, &sin6, sizeof(sin6));
2703		break;
2704	default:
2705		dprintk("RPC:       %s: Bad address family\n", __func__);
2706		return -EAFNOSUPPORT;
2707	}
2708	return 0;
2709}
2710
2711static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2712				      unsigned int slot_table_size,
2713				      unsigned int max_slot_table_size)
2714{
2715	struct rpc_xprt *xprt;
2716	struct sock_xprt *new;
2717
2718	if (args->addrlen > sizeof(xprt->addr)) {
2719		dprintk("RPC:       xs_setup_xprt: address too large\n");
2720		return ERR_PTR(-EBADF);
2721	}
2722
2723	xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2724			max_slot_table_size);
2725	if (xprt == NULL) {
2726		dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2727				"rpc_xprt\n");
2728		return ERR_PTR(-ENOMEM);
2729	}
2730
2731	new = container_of(xprt, struct sock_xprt, xprt);
2732	mutex_init(&new->recv_mutex);
2733	memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2734	xprt->addrlen = args->addrlen;
2735	if (args->srcaddr)
2736		memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2737	else {
2738		int err;
2739		err = xs_init_anyaddr(args->dstaddr->sa_family,
2740					(struct sockaddr *)&new->srcaddr);
2741		if (err != 0) {
2742			xprt_free(xprt);
2743			return ERR_PTR(err);
2744		}
2745	}
2746
2747	return xprt;
2748}
2749
2750static const struct rpc_timeout xs_local_default_timeout = {
2751	.to_initval = 10 * HZ,
2752	.to_maxval = 10 * HZ,
2753	.to_retries = 2,
2754};
2755
2756/**
2757 * xs_setup_local - Set up transport to use an AF_LOCAL socket
2758 * @args: rpc transport creation arguments
2759 *
2760 * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2761 */
2762static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2763{
2764	struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2765	struct sock_xprt *transport;
2766	struct rpc_xprt *xprt;
2767	struct rpc_xprt *ret;
2768
2769	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2770			xprt_max_tcp_slot_table_entries);
2771	if (IS_ERR(xprt))
2772		return xprt;
2773	transport = container_of(xprt, struct sock_xprt, xprt);
2774
2775	xprt->prot = 0;
2776	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2777
2778	xprt->bind_timeout = XS_BIND_TO;
2779	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2780	xprt->idle_timeout = XS_IDLE_DISC_TO;
2781
2782	xprt->ops = &xs_local_ops;
2783	xprt->timeout = &xs_local_default_timeout;
2784
2785	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2786	INIT_WORK(&transport->error_worker, xs_error_handle);
2787	INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket);
2788
2789	switch (sun->sun_family) {
2790	case AF_LOCAL:
2791		if (sun->sun_path[0] != '/') {
2792			dprintk("RPC:       bad AF_LOCAL address: %s\n",
2793					sun->sun_path);
2794			ret = ERR_PTR(-EINVAL);
2795			goto out_err;
2796		}
2797		xprt_set_bound(xprt);
2798		xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
2799		ret = ERR_PTR(xs_local_setup_socket(transport));
2800		if (ret)
2801			goto out_err;
2802		break;
2803	default:
2804		ret = ERR_PTR(-EAFNOSUPPORT);
2805		goto out_err;
2806	}
2807
2808	dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
2809			xprt->address_strings[RPC_DISPLAY_ADDR]);
2810
2811	if (try_module_get(THIS_MODULE))
2812		return xprt;
2813	ret = ERR_PTR(-EINVAL);
2814out_err:
2815	xs_xprt_free(xprt);
2816	return ret;
2817}
2818
2819static const struct rpc_timeout xs_udp_default_timeout = {
2820	.to_initval = 5 * HZ,
2821	.to_maxval = 30 * HZ,
2822	.to_increment = 5 * HZ,
2823	.to_retries = 5,
2824};
2825
2826/**
2827 * xs_setup_udp - Set up transport to use a UDP socket
2828 * @args: rpc transport creation arguments
2829 *
2830 */
2831static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2832{
2833	struct sockaddr *addr = args->dstaddr;
2834	struct rpc_xprt *xprt;
2835	struct sock_xprt *transport;
2836	struct rpc_xprt *ret;
2837
2838	xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2839			xprt_udp_slot_table_entries);
2840	if (IS_ERR(xprt))
2841		return xprt;
2842	transport = container_of(xprt, struct sock_xprt, xprt);
2843
2844	xprt->prot = IPPROTO_UDP;
2845	/* XXX: header size can vary due to auth type, IPv6, etc. */
2846	xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2847
2848	xprt->bind_timeout = XS_BIND_TO;
2849	xprt->reestablish_timeout = XS_UDP_REEST_TO;
2850	xprt->idle_timeout = XS_IDLE_DISC_TO;
2851
2852	xprt->ops = &xs_udp_ops;
2853
2854	xprt->timeout = &xs_udp_default_timeout;
2855
2856	INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
2857	INIT_WORK(&transport->error_worker, xs_error_handle);
2858	INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
2859
2860	switch (addr->sa_family) {
2861	case AF_INET:
2862		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2863			xprt_set_bound(xprt);
2864
2865		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2866		break;
2867	case AF_INET6:
2868		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2869			xprt_set_bound(xprt);
2870
2871		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2872		break;
2873	default:
2874		ret = ERR_PTR(-EAFNOSUPPORT);
2875		goto out_err;
2876	}
2877
2878	if (xprt_bound(xprt))
2879		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2880				xprt->address_strings[RPC_DISPLAY_ADDR],
2881				xprt->address_strings[RPC_DISPLAY_PORT],
2882				xprt->address_strings[RPC_DISPLAY_PROTO]);
2883	else
2884		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2885				xprt->address_strings[RPC_DISPLAY_ADDR],
2886				xprt->address_strings[RPC_DISPLAY_PROTO]);
2887
2888	if (try_module_get(THIS_MODULE))
2889		return xprt;
2890	ret = ERR_PTR(-EINVAL);
2891out_err:
2892	xs_xprt_free(xprt);
2893	return ret;
2894}
2895
2896static const struct rpc_timeout xs_tcp_default_timeout = {
2897	.to_initval = 60 * HZ,
2898	.to_maxval = 60 * HZ,
2899	.to_retries = 2,
2900};
2901
2902/**
2903 * xs_setup_tcp - Set up transport to use a TCP socket
2904 * @args: rpc transport creation arguments
2905 *
2906 */
2907static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2908{
2909	struct sockaddr *addr = args->dstaddr;
2910	struct rpc_xprt *xprt;
2911	struct sock_xprt *transport;
2912	struct rpc_xprt *ret;
2913	unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
2914
2915	if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
2916		max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
2917
2918	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2919			max_slot_table_size);
2920	if (IS_ERR(xprt))
2921		return xprt;
2922	transport = container_of(xprt, struct sock_xprt, xprt);
2923
2924	xprt->prot = IPPROTO_TCP;
2925	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2926
2927	xprt->bind_timeout = XS_BIND_TO;
2928	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2929	xprt->idle_timeout = XS_IDLE_DISC_TO;
2930
2931	xprt->ops = &xs_tcp_ops;
2932	xprt->timeout = &xs_tcp_default_timeout;
2933
2934	xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
2935	xprt->connect_timeout = xprt->timeout->to_initval *
2936		(xprt->timeout->to_retries + 1);
2937
2938	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2939	INIT_WORK(&transport->error_worker, xs_error_handle);
2940	INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
2941
2942	switch (addr->sa_family) {
2943	case AF_INET:
2944		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2945			xprt_set_bound(xprt);
2946
2947		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
2948		break;
2949	case AF_INET6:
2950		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2951			xprt_set_bound(xprt);
2952
2953		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
2954		break;
2955	default:
2956		ret = ERR_PTR(-EAFNOSUPPORT);
2957		goto out_err;
2958	}
2959
2960	if (xprt_bound(xprt))
2961		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2962				xprt->address_strings[RPC_DISPLAY_ADDR],
2963				xprt->address_strings[RPC_DISPLAY_PORT],
2964				xprt->address_strings[RPC_DISPLAY_PROTO]);
2965	else
2966		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2967				xprt->address_strings[RPC_DISPLAY_ADDR],
2968				xprt->address_strings[RPC_DISPLAY_PROTO]);
2969
2970	if (try_module_get(THIS_MODULE))
2971		return xprt;
2972	ret = ERR_PTR(-EINVAL);
2973out_err:
2974	xs_xprt_free(xprt);
2975	return ret;
2976}
2977
2978/**
2979 * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
2980 * @args: rpc transport creation arguments
2981 *
2982 */
2983static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
2984{
2985	struct sockaddr *addr = args->dstaddr;
2986	struct rpc_xprt *xprt;
2987	struct sock_xprt *transport;
2988	struct svc_sock *bc_sock;
2989	struct rpc_xprt *ret;
2990
2991	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2992			xprt_tcp_slot_table_entries);
2993	if (IS_ERR(xprt))
2994		return xprt;
2995	transport = container_of(xprt, struct sock_xprt, xprt);
2996
2997	xprt->prot = IPPROTO_TCP;
2998	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2999	xprt->timeout = &xs_tcp_default_timeout;
3000
3001	/* backchannel */
3002	xprt_set_bound(xprt);
3003	xprt->bind_timeout = 0;
3004	xprt->reestablish_timeout = 0;
3005	xprt->idle_timeout = 0;
3006
3007	xprt->ops = &bc_tcp_ops;
3008
3009	switch (addr->sa_family) {
3010	case AF_INET:
3011		xs_format_peer_addresses(xprt, "tcp",
3012					 RPCBIND_NETID_TCP);
3013		break;
3014	case AF_INET6:
3015		xs_format_peer_addresses(xprt, "tcp",
3016				   RPCBIND_NETID_TCP6);
3017		break;
3018	default:
3019		ret = ERR_PTR(-EAFNOSUPPORT);
3020		goto out_err;
3021	}
3022
3023	dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3024			xprt->address_strings[RPC_DISPLAY_ADDR],
3025			xprt->address_strings[RPC_DISPLAY_PORT],
3026			xprt->address_strings[RPC_DISPLAY_PROTO]);
3027
3028	/*
3029	 * Once we've associated a backchannel xprt with a connection,
3030	 * we want to keep it around as long as the connection lasts,
3031	 * in case we need to start using it for a backchannel again;
3032	 * this reference won't be dropped until bc_xprt is destroyed.
3033	 */
3034	xprt_get(xprt);
3035	args->bc_xprt->xpt_bc_xprt = xprt;
3036	xprt->bc_xprt = args->bc_xprt;
3037	bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3038	transport->sock = bc_sock->sk_sock;
3039	transport->inet = bc_sock->sk_sk;
3040
3041	/*
3042	 * Since we don't want connections for the backchannel, we set
3043	 * the xprt status to connected
3044	 */
3045	xprt_set_connected(xprt);
3046
3047	if (try_module_get(THIS_MODULE))
3048		return xprt;
3049
3050	args->bc_xprt->xpt_bc_xprt = NULL;
3051	args->bc_xprt->xpt_bc_xps = NULL;
3052	xprt_put(xprt);
3053	ret = ERR_PTR(-EINVAL);
3054out_err:
3055	xs_xprt_free(xprt);
3056	return ret;
3057}
3058
3059static struct xprt_class	xs_local_transport = {
3060	.list		= LIST_HEAD_INIT(xs_local_transport.list),
3061	.name		= "named UNIX socket",
3062	.owner		= THIS_MODULE,
3063	.ident		= XPRT_TRANSPORT_LOCAL,
3064	.setup		= xs_setup_local,
3065};
3066
3067static struct xprt_class	xs_udp_transport = {
3068	.list		= LIST_HEAD_INIT(xs_udp_transport.list),
3069	.name		= "udp",
3070	.owner		= THIS_MODULE,
3071	.ident		= XPRT_TRANSPORT_UDP,
3072	.setup		= xs_setup_udp,
3073};
3074
3075static struct xprt_class	xs_tcp_transport = {
3076	.list		= LIST_HEAD_INIT(xs_tcp_transport.list),
3077	.name		= "tcp",
3078	.owner		= THIS_MODULE,
3079	.ident		= XPRT_TRANSPORT_TCP,
3080	.setup		= xs_setup_tcp,
3081};
3082
3083static struct xprt_class	xs_bc_tcp_transport = {
3084	.list		= LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3085	.name		= "tcp NFSv4.1 backchannel",
3086	.owner		= THIS_MODULE,
3087	.ident		= XPRT_TRANSPORT_BC_TCP,
3088	.setup		= xs_setup_bc_tcp,
3089};
3090
3091/**
3092 * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3093 *
3094 */
3095int init_socket_xprt(void)
3096{
3097	if (!sunrpc_table_header)
3098		sunrpc_table_header = register_sysctl_table(sunrpc_table);
3099
3100	xprt_register_transport(&xs_local_transport);
3101	xprt_register_transport(&xs_udp_transport);
3102	xprt_register_transport(&xs_tcp_transport);
3103	xprt_register_transport(&xs_bc_tcp_transport);
3104
3105	return 0;
3106}
3107
3108/**
3109 * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3110 *
3111 */
3112void cleanup_socket_xprt(void)
3113{
3114	if (sunrpc_table_header) {
3115		unregister_sysctl_table(sunrpc_table_header);
3116		sunrpc_table_header = NULL;
3117	}
3118
3119	xprt_unregister_transport(&xs_local_transport);
3120	xprt_unregister_transport(&xs_udp_transport);
3121	xprt_unregister_transport(&xs_tcp_transport);
3122	xprt_unregister_transport(&xs_bc_tcp_transport);
3123}
3124
3125static int param_set_uint_minmax(const char *val,
3126		const struct kernel_param *kp,
3127		unsigned int min, unsigned int max)
3128{
3129	unsigned int num;
3130	int ret;
3131
3132	if (!val)
3133		return -EINVAL;
3134	ret = kstrtouint(val, 0, &num);
3135	if (ret)
3136		return ret;
3137	if (num < min || num > max)
3138		return -EINVAL;
3139	*((unsigned int *)kp->arg) = num;
3140	return 0;
3141}
3142
3143static int param_set_portnr(const char *val, const struct kernel_param *kp)
3144{
3145	return param_set_uint_minmax(val, kp,
3146			RPC_MIN_RESVPORT,
3147			RPC_MAX_RESVPORT);
3148}
3149
3150static const struct kernel_param_ops param_ops_portnr = {
3151	.set = param_set_portnr,
3152	.get = param_get_uint,
3153};
3154
3155#define param_check_portnr(name, p) \
3156	__param_check(name, p, unsigned int);
3157
3158module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3159module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3160
3161static int param_set_slot_table_size(const char *val,
3162				     const struct kernel_param *kp)
3163{
3164	return param_set_uint_minmax(val, kp,
3165			RPC_MIN_SLOT_TABLE,
3166			RPC_MAX_SLOT_TABLE);
3167}
3168
3169static const struct kernel_param_ops param_ops_slot_table_size = {
3170	.set = param_set_slot_table_size,
3171	.get = param_get_uint,
3172};
3173
3174#define param_check_slot_table_size(name, p) \
3175	__param_check(name, p, unsigned int);
3176
3177static int param_set_max_slot_table_size(const char *val,
3178				     const struct kernel_param *kp)
3179{
3180	return param_set_uint_minmax(val, kp,
3181			RPC_MIN_SLOT_TABLE,
3182			RPC_MAX_SLOT_TABLE_LIMIT);
3183}
3184
3185static const struct kernel_param_ops param_ops_max_slot_table_size = {
3186	.set = param_set_max_slot_table_size,
3187	.get = param_get_uint,
3188};
3189
3190#define param_check_max_slot_table_size(name, p) \
3191	__param_check(name, p, unsigned int);
3192
3193module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3194		   slot_table_size, 0644);
3195module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3196		   max_slot_table_size, 0644);
3197module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3198		   slot_table_size, 0644);
v5.4
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * linux/net/sunrpc/xprtsock.c
   4 *
   5 * Client-side transport implementation for sockets.
   6 *
   7 * TCP callback races fixes (C) 1998 Red Hat
   8 * TCP send fixes (C) 1998 Red Hat
   9 * TCP NFS related read + write fixes
  10 *  (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
  11 *
  12 * Rewrite of larges part of the code in order to stabilize TCP stuff.
  13 * Fix behaviour when socket buffer is full.
  14 *  (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no>
  15 *
  16 * IP socket transport implementation, (C) 2005 Chuck Lever <cel@netapp.com>
  17 *
  18 * IPv6 support contributed by Gilles Quillard, Bull Open Source, 2005.
  19 *   <gilles.quillard@bull.net>
  20 */
  21
  22#include <linux/types.h>
  23#include <linux/string.h>
  24#include <linux/slab.h>
  25#include <linux/module.h>
  26#include <linux/capability.h>
  27#include <linux/pagemap.h>
  28#include <linux/errno.h>
  29#include <linux/socket.h>
  30#include <linux/in.h>
  31#include <linux/net.h>
  32#include <linux/mm.h>
  33#include <linux/un.h>
  34#include <linux/udp.h>
  35#include <linux/tcp.h>
  36#include <linux/sunrpc/clnt.h>
  37#include <linux/sunrpc/addr.h>
  38#include <linux/sunrpc/sched.h>
  39#include <linux/sunrpc/svcsock.h>
  40#include <linux/sunrpc/xprtsock.h>
  41#include <linux/file.h>
  42#ifdef CONFIG_SUNRPC_BACKCHANNEL
  43#include <linux/sunrpc/bc_xprt.h>
  44#endif
  45
  46#include <net/sock.h>
  47#include <net/checksum.h>
  48#include <net/udp.h>
  49#include <net/tcp.h>
  50#include <linux/bvec.h>
  51#include <linux/highmem.h>
  52#include <linux/uio.h>
  53#include <linux/sched/mm.h>
  54
  55#include <trace/events/sunrpc.h>
  56
 
  57#include "sunrpc.h"
  58
  59static void xs_close(struct rpc_xprt *xprt);
  60static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
  61		struct socket *sock);
  62
  63/*
  64 * xprtsock tunables
  65 */
  66static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  67static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
  68static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
  69
  70static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
  71static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
  72
  73#define XS_TCP_LINGER_TO	(15U * HZ)
  74static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
  75
  76/*
  77 * We can register our own files under /proc/sys/sunrpc by
  78 * calling register_sysctl_table() again.  The files in that
  79 * directory become the union of all files registered there.
  80 *
  81 * We simply need to make sure that we don't collide with
  82 * someone else's file names!
  83 */
  84
  85static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
  86static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
  87static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
  88static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
  89static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
  90
  91static struct ctl_table_header *sunrpc_table_header;
  92
  93/*
  94 * FIXME: changing the UDP slot table size should also resize the UDP
  95 *        socket buffers for existing UDP transports
  96 */
  97static struct ctl_table xs_tunables_table[] = {
  98	{
  99		.procname	= "udp_slot_table_entries",
 100		.data		= &xprt_udp_slot_table_entries,
 101		.maxlen		= sizeof(unsigned int),
 102		.mode		= 0644,
 103		.proc_handler	= proc_dointvec_minmax,
 104		.extra1		= &min_slot_table_size,
 105		.extra2		= &max_slot_table_size
 106	},
 107	{
 108		.procname	= "tcp_slot_table_entries",
 109		.data		= &xprt_tcp_slot_table_entries,
 110		.maxlen		= sizeof(unsigned int),
 111		.mode		= 0644,
 112		.proc_handler	= proc_dointvec_minmax,
 113		.extra1		= &min_slot_table_size,
 114		.extra2		= &max_slot_table_size
 115	},
 116	{
 117		.procname	= "tcp_max_slot_table_entries",
 118		.data		= &xprt_max_tcp_slot_table_entries,
 119		.maxlen		= sizeof(unsigned int),
 120		.mode		= 0644,
 121		.proc_handler	= proc_dointvec_minmax,
 122		.extra1		= &min_slot_table_size,
 123		.extra2		= &max_tcp_slot_table_limit
 124	},
 125	{
 126		.procname	= "min_resvport",
 127		.data		= &xprt_min_resvport,
 128		.maxlen		= sizeof(unsigned int),
 129		.mode		= 0644,
 130		.proc_handler	= proc_dointvec_minmax,
 131		.extra1		= &xprt_min_resvport_limit,
 132		.extra2		= &xprt_max_resvport_limit
 133	},
 134	{
 135		.procname	= "max_resvport",
 136		.data		= &xprt_max_resvport,
 137		.maxlen		= sizeof(unsigned int),
 138		.mode		= 0644,
 139		.proc_handler	= proc_dointvec_minmax,
 140		.extra1		= &xprt_min_resvport_limit,
 141		.extra2		= &xprt_max_resvport_limit
 142	},
 143	{
 144		.procname	= "tcp_fin_timeout",
 145		.data		= &xs_tcp_fin_timeout,
 146		.maxlen		= sizeof(xs_tcp_fin_timeout),
 147		.mode		= 0644,
 148		.proc_handler	= proc_dointvec_jiffies,
 149	},
 150	{ },
 151};
 152
 153static struct ctl_table sunrpc_table[] = {
 154	{
 155		.procname	= "sunrpc",
 156		.mode		= 0555,
 157		.child		= xs_tunables_table
 158	},
 159	{ },
 160};
 161
 162/*
 163 * Wait duration for a reply from the RPC portmapper.
 164 */
 165#define XS_BIND_TO		(60U * HZ)
 166
 167/*
 168 * Delay if a UDP socket connect error occurs.  This is most likely some
 169 * kind of resource problem on the local host.
 170 */
 171#define XS_UDP_REEST_TO		(2U * HZ)
 172
 173/*
 174 * The reestablish timeout allows clients to delay for a bit before attempting
 175 * to reconnect to a server that just dropped our connection.
 176 *
 177 * We implement an exponential backoff when trying to reestablish a TCP
 178 * transport connection with the server.  Some servers like to drop a TCP
 179 * connection when they are overworked, so we start with a short timeout and
 180 * increase over time if the server is down or not responding.
 181 */
 182#define XS_TCP_INIT_REEST_TO	(3U * HZ)
 183
 184/*
 185 * TCP idle timeout; client drops the transport socket if it is idle
 186 * for this long.  Note that we also timeout UDP sockets to prevent
 187 * holding port numbers when there is no RPC traffic.
 188 */
 189#define XS_IDLE_DISC_TO		(5U * 60 * HZ)
 190
 191#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 192# undef  RPC_DEBUG_DATA
 193# define RPCDBG_FACILITY	RPCDBG_TRANS
 194#endif
 195
 196#ifdef RPC_DEBUG_DATA
 197static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 198{
 199	u8 *buf = (u8 *) packet;
 200	int j;
 201
 202	dprintk("RPC:       %s\n", msg);
 203	for (j = 0; j < count && j < 128; j += 4) {
 204		if (!(j & 31)) {
 205			if (j)
 206				dprintk("\n");
 207			dprintk("0x%04x ", j);
 208		}
 209		dprintk("%02x%02x%02x%02x ",
 210			buf[j], buf[j+1], buf[j+2], buf[j+3]);
 211	}
 212	dprintk("\n");
 213}
 214#else
 215static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 216{
 217	/* NOP */
 218}
 219#endif
 220
 221static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
 222{
 223	return (struct rpc_xprt *) sk->sk_user_data;
 224}
 225
 226static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
 227{
 228	return (struct sockaddr *) &xprt->addr;
 229}
 230
 231static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
 232{
 233	return (struct sockaddr_un *) &xprt->addr;
 234}
 235
 236static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
 237{
 238	return (struct sockaddr_in *) &xprt->addr;
 239}
 240
 241static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
 242{
 243	return (struct sockaddr_in6 *) &xprt->addr;
 244}
 245
 246static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
 247{
 248	struct sockaddr *sap = xs_addr(xprt);
 249	struct sockaddr_in6 *sin6;
 250	struct sockaddr_in *sin;
 251	struct sockaddr_un *sun;
 252	char buf[128];
 253
 254	switch (sap->sa_family) {
 255	case AF_LOCAL:
 256		sun = xs_addr_un(xprt);
 257		strlcpy(buf, sun->sun_path, sizeof(buf));
 258		xprt->address_strings[RPC_DISPLAY_ADDR] =
 259						kstrdup(buf, GFP_KERNEL);
 260		break;
 261	case AF_INET:
 262		(void)rpc_ntop(sap, buf, sizeof(buf));
 263		xprt->address_strings[RPC_DISPLAY_ADDR] =
 264						kstrdup(buf, GFP_KERNEL);
 265		sin = xs_addr_in(xprt);
 266		snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
 267		break;
 268	case AF_INET6:
 269		(void)rpc_ntop(sap, buf, sizeof(buf));
 270		xprt->address_strings[RPC_DISPLAY_ADDR] =
 271						kstrdup(buf, GFP_KERNEL);
 272		sin6 = xs_addr_in6(xprt);
 273		snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
 274		break;
 275	default:
 276		BUG();
 277	}
 278
 279	xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
 280}
 281
 282static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
 283{
 284	struct sockaddr *sap = xs_addr(xprt);
 285	char buf[128];
 286
 287	snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
 288	xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
 289
 290	snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
 291	xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
 292}
 293
 294static void xs_format_peer_addresses(struct rpc_xprt *xprt,
 295				     const char *protocol,
 296				     const char *netid)
 297{
 298	xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
 299	xprt->address_strings[RPC_DISPLAY_NETID] = netid;
 300	xs_format_common_peer_addresses(xprt);
 301	xs_format_common_peer_ports(xprt);
 302}
 303
 304static void xs_update_peer_port(struct rpc_xprt *xprt)
 305{
 306	kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
 307	kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
 308
 309	xs_format_common_peer_ports(xprt);
 310}
 311
 312static void xs_free_peer_addresses(struct rpc_xprt *xprt)
 313{
 314	unsigned int i;
 315
 316	for (i = 0; i < RPC_DISPLAY_MAX; i++)
 317		switch (i) {
 318		case RPC_DISPLAY_PROTO:
 319		case RPC_DISPLAY_NETID:
 320			continue;
 321		default:
 322			kfree(xprt->address_strings[i]);
 323		}
 324}
 325
 326static size_t
 327xs_alloc_sparse_pages(struct xdr_buf *buf, size_t want, gfp_t gfp)
 328{
 329	size_t i,n;
 330
 331	if (!want || !(buf->flags & XDRBUF_SPARSE_PAGES))
 332		return want;
 333	n = (buf->page_base + want + PAGE_SIZE - 1) >> PAGE_SHIFT;
 334	for (i = 0; i < n; i++) {
 335		if (buf->pages[i])
 336			continue;
 337		buf->bvec[i].bv_page = buf->pages[i] = alloc_page(gfp);
 338		if (!buf->pages[i]) {
 339			i *= PAGE_SIZE;
 340			return i > buf->page_base ? i - buf->page_base : 0;
 341		}
 342	}
 343	return want;
 344}
 345
 346static ssize_t
 347xs_sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags, size_t seek)
 348{
 349	ssize_t ret;
 350	if (seek != 0)
 351		iov_iter_advance(&msg->msg_iter, seek);
 352	ret = sock_recvmsg(sock, msg, flags);
 353	return ret > 0 ? ret + seek : ret;
 354}
 355
 356static ssize_t
 357xs_read_kvec(struct socket *sock, struct msghdr *msg, int flags,
 358		struct kvec *kvec, size_t count, size_t seek)
 359{
 360	iov_iter_kvec(&msg->msg_iter, READ, kvec, 1, count);
 361	return xs_sock_recvmsg(sock, msg, flags, seek);
 362}
 363
 364static ssize_t
 365xs_read_bvec(struct socket *sock, struct msghdr *msg, int flags,
 366		struct bio_vec *bvec, unsigned long nr, size_t count,
 367		size_t seek)
 368{
 369	iov_iter_bvec(&msg->msg_iter, READ, bvec, nr, count);
 370	return xs_sock_recvmsg(sock, msg, flags, seek);
 371}
 372
 373static ssize_t
 374xs_read_discard(struct socket *sock, struct msghdr *msg, int flags,
 375		size_t count)
 376{
 377	iov_iter_discard(&msg->msg_iter, READ, count);
 378	return sock_recvmsg(sock, msg, flags);
 379}
 380
 381#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
 382static void
 383xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
 384{
 385	struct bvec_iter bi = {
 386		.bi_size = count,
 387	};
 388	struct bio_vec bv;
 389
 390	bvec_iter_advance(bvec, &bi, seek & PAGE_MASK);
 391	for_each_bvec(bv, bvec, bi, bi)
 392		flush_dcache_page(bv.bv_page);
 393}
 394#else
 395static inline void
 396xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
 397{
 398}
 399#endif
 400
 401static ssize_t
 402xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags,
 403		struct xdr_buf *buf, size_t count, size_t seek, size_t *read)
 404{
 405	size_t want, seek_init = seek, offset = 0;
 406	ssize_t ret;
 407
 408	want = min_t(size_t, count, buf->head[0].iov_len);
 409	if (seek < want) {
 410		ret = xs_read_kvec(sock, msg, flags, &buf->head[0], want, seek);
 411		if (ret <= 0)
 412			goto sock_err;
 413		offset += ret;
 414		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 415			goto out;
 416		if (ret != want)
 417			goto out;
 418		seek = 0;
 419	} else {
 420		seek -= want;
 421		offset += want;
 422	}
 423
 424	want = xs_alloc_sparse_pages(buf,
 425			min_t(size_t, count - offset, buf->page_len),
 426			GFP_KERNEL);
 427	if (seek < want) {
 428		ret = xs_read_bvec(sock, msg, flags, buf->bvec,
 429				xdr_buf_pagecount(buf),
 430				want + buf->page_base,
 431				seek + buf->page_base);
 432		if (ret <= 0)
 433			goto sock_err;
 434		xs_flush_bvec(buf->bvec, ret, seek + buf->page_base);
 435		offset += ret - buf->page_base;
 436		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 437			goto out;
 438		if (ret != want)
 439			goto out;
 440		seek = 0;
 441	} else {
 442		seek -= want;
 443		offset += want;
 444	}
 445
 446	want = min_t(size_t, count - offset, buf->tail[0].iov_len);
 447	if (seek < want) {
 448		ret = xs_read_kvec(sock, msg, flags, &buf->tail[0], want, seek);
 449		if (ret <= 0)
 450			goto sock_err;
 451		offset += ret;
 452		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 453			goto out;
 454		if (ret != want)
 455			goto out;
 456	} else if (offset < seek_init)
 457		offset = seek_init;
 458	ret = -EMSGSIZE;
 459out:
 460	*read = offset - seek_init;
 461	return ret;
 462sock_err:
 463	offset += seek;
 464	goto out;
 465}
 466
 467static void
 468xs_read_header(struct sock_xprt *transport, struct xdr_buf *buf)
 469{
 470	if (!transport->recv.copied) {
 471		if (buf->head[0].iov_len >= transport->recv.offset)
 472			memcpy(buf->head[0].iov_base,
 473					&transport->recv.xid,
 474					transport->recv.offset);
 475		transport->recv.copied = transport->recv.offset;
 476	}
 477}
 478
 479static bool
 480xs_read_stream_request_done(struct sock_xprt *transport)
 481{
 482	return transport->recv.fraghdr & cpu_to_be32(RPC_LAST_STREAM_FRAGMENT);
 483}
 484
 485static void
 486xs_read_stream_check_eor(struct sock_xprt *transport,
 487		struct msghdr *msg)
 488{
 489	if (xs_read_stream_request_done(transport))
 490		msg->msg_flags |= MSG_EOR;
 491}
 492
 493static ssize_t
 494xs_read_stream_request(struct sock_xprt *transport, struct msghdr *msg,
 495		int flags, struct rpc_rqst *req)
 496{
 497	struct xdr_buf *buf = &req->rq_private_buf;
 498	size_t want, uninitialized_var(read);
 499	ssize_t uninitialized_var(ret);
 500
 501	xs_read_header(transport, buf);
 502
 503	want = transport->recv.len - transport->recv.offset;
 504	if (want != 0) {
 505		ret = xs_read_xdr_buf(transport->sock, msg, flags, buf,
 506				transport->recv.copied + want,
 507				transport->recv.copied,
 508				&read);
 509		transport->recv.offset += read;
 510		transport->recv.copied += read;
 511	}
 512
 513	if (transport->recv.offset == transport->recv.len)
 514		xs_read_stream_check_eor(transport, msg);
 515
 516	if (want == 0)
 517		return 0;
 518
 519	switch (ret) {
 520	default:
 521		break;
 522	case -EFAULT:
 523	case -EMSGSIZE:
 524		msg->msg_flags |= MSG_TRUNC;
 525		return read;
 526	case 0:
 527		return -ESHUTDOWN;
 528	}
 529	return ret < 0 ? ret : read;
 530}
 531
 532static size_t
 533xs_read_stream_headersize(bool isfrag)
 534{
 535	if (isfrag)
 536		return sizeof(__be32);
 537	return 3 * sizeof(__be32);
 538}
 539
 540static ssize_t
 541xs_read_stream_header(struct sock_xprt *transport, struct msghdr *msg,
 542		int flags, size_t want, size_t seek)
 543{
 544	struct kvec kvec = {
 545		.iov_base = &transport->recv.fraghdr,
 546		.iov_len = want,
 547	};
 548	return xs_read_kvec(transport->sock, msg, flags, &kvec, want, seek);
 549}
 550
 551#if defined(CONFIG_SUNRPC_BACKCHANNEL)
 552static ssize_t
 553xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 554{
 555	struct rpc_xprt *xprt = &transport->xprt;
 556	struct rpc_rqst *req;
 557	ssize_t ret;
 558
 559	/* Look up and lock the request corresponding to the given XID */
 560	req = xprt_lookup_bc_request(xprt, transport->recv.xid);
 561	if (!req) {
 562		printk(KERN_WARNING "Callback slot table overflowed\n");
 563		return -ESHUTDOWN;
 564	}
 565	if (transport->recv.copied && !req->rq_private_buf.len)
 566		return -ESHUTDOWN;
 567
 568	ret = xs_read_stream_request(transport, msg, flags, req);
 569	if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 570		xprt_complete_bc_request(req, transport->recv.copied);
 571	else
 572		req->rq_private_buf.len = transport->recv.copied;
 573
 574	return ret;
 575}
 576#else /* CONFIG_SUNRPC_BACKCHANNEL */
 577static ssize_t
 578xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 579{
 580	return -ESHUTDOWN;
 581}
 582#endif /* CONFIG_SUNRPC_BACKCHANNEL */
 583
 584static ssize_t
 585xs_read_stream_reply(struct sock_xprt *transport, struct msghdr *msg, int flags)
 586{
 587	struct rpc_xprt *xprt = &transport->xprt;
 588	struct rpc_rqst *req;
 589	ssize_t ret = 0;
 590
 591	/* Look up and lock the request corresponding to the given XID */
 592	spin_lock(&xprt->queue_lock);
 593	req = xprt_lookup_rqst(xprt, transport->recv.xid);
 594	if (!req || (transport->recv.copied && !req->rq_private_buf.len)) {
 595		msg->msg_flags |= MSG_TRUNC;
 596		goto out;
 597	}
 598	xprt_pin_rqst(req);
 599	spin_unlock(&xprt->queue_lock);
 600
 601	ret = xs_read_stream_request(transport, msg, flags, req);
 602
 603	spin_lock(&xprt->queue_lock);
 604	if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 605		xprt_complete_rqst(req->rq_task, transport->recv.copied);
 606	else
 607		req->rq_private_buf.len = transport->recv.copied;
 608	xprt_unpin_rqst(req);
 609out:
 610	spin_unlock(&xprt->queue_lock);
 611	return ret;
 612}
 613
 614static ssize_t
 615xs_read_stream(struct sock_xprt *transport, int flags)
 616{
 617	struct msghdr msg = { 0 };
 618	size_t want, read = 0;
 619	ssize_t ret = 0;
 620
 621	if (transport->recv.len == 0) {
 622		want = xs_read_stream_headersize(transport->recv.copied != 0);
 623		ret = xs_read_stream_header(transport, &msg, flags, want,
 624				transport->recv.offset);
 625		if (ret <= 0)
 626			goto out_err;
 627		transport->recv.offset = ret;
 628		if (transport->recv.offset != want)
 629			return transport->recv.offset;
 630		transport->recv.len = be32_to_cpu(transport->recv.fraghdr) &
 631			RPC_FRAGMENT_SIZE_MASK;
 632		transport->recv.offset -= sizeof(transport->recv.fraghdr);
 633		read = ret;
 634	}
 635
 636	switch (be32_to_cpu(transport->recv.calldir)) {
 637	default:
 638		msg.msg_flags |= MSG_TRUNC;
 639		break;
 640	case RPC_CALL:
 641		ret = xs_read_stream_call(transport, &msg, flags);
 642		break;
 643	case RPC_REPLY:
 644		ret = xs_read_stream_reply(transport, &msg, flags);
 645	}
 646	if (msg.msg_flags & MSG_TRUNC) {
 647		transport->recv.calldir = cpu_to_be32(-1);
 648		transport->recv.copied = -1;
 649	}
 650	if (ret < 0)
 651		goto out_err;
 652	read += ret;
 653	if (transport->recv.offset < transport->recv.len) {
 654		if (!(msg.msg_flags & MSG_TRUNC))
 655			return read;
 656		msg.msg_flags = 0;
 657		ret = xs_read_discard(transport->sock, &msg, flags,
 658				transport->recv.len - transport->recv.offset);
 659		if (ret <= 0)
 660			goto out_err;
 661		transport->recv.offset += ret;
 662		read += ret;
 663		if (transport->recv.offset != transport->recv.len)
 664			return read;
 665	}
 666	if (xs_read_stream_request_done(transport)) {
 667		trace_xs_stream_read_request(transport);
 668		transport->recv.copied = 0;
 669	}
 670	transport->recv.offset = 0;
 671	transport->recv.len = 0;
 672	return read;
 673out_err:
 674	return ret != 0 ? ret : -ESHUTDOWN;
 675}
 676
 677static __poll_t xs_poll_socket(struct sock_xprt *transport)
 678{
 679	return transport->sock->ops->poll(transport->file, transport->sock,
 680			NULL);
 681}
 682
 683static bool xs_poll_socket_readable(struct sock_xprt *transport)
 684{
 685	__poll_t events = xs_poll_socket(transport);
 686
 687	return (events & (EPOLLIN | EPOLLRDNORM)) && !(events & EPOLLRDHUP);
 688}
 689
 690static void xs_poll_check_readable(struct sock_xprt *transport)
 691{
 692
 693	clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
 694	if (!xs_poll_socket_readable(transport))
 695		return;
 696	if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
 697		queue_work(xprtiod_workqueue, &transport->recv_worker);
 698}
 699
 700static void xs_stream_data_receive(struct sock_xprt *transport)
 701{
 702	size_t read = 0;
 703	ssize_t ret = 0;
 704
 705	mutex_lock(&transport->recv_mutex);
 706	if (transport->sock == NULL)
 707		goto out;
 708	for (;;) {
 709		ret = xs_read_stream(transport, MSG_DONTWAIT);
 710		if (ret < 0)
 711			break;
 712		read += ret;
 713		cond_resched();
 714	}
 715	if (ret == -ESHUTDOWN)
 716		kernel_sock_shutdown(transport->sock, SHUT_RDWR);
 717	else
 718		xs_poll_check_readable(transport);
 719out:
 720	mutex_unlock(&transport->recv_mutex);
 721	trace_xs_stream_read_data(&transport->xprt, ret, read);
 722}
 723
 724static void xs_stream_data_receive_workfn(struct work_struct *work)
 725{
 726	struct sock_xprt *transport =
 727		container_of(work, struct sock_xprt, recv_worker);
 728	unsigned int pflags = memalloc_nofs_save();
 729
 730	xs_stream_data_receive(transport);
 731	memalloc_nofs_restore(pflags);
 732}
 733
 734static void
 735xs_stream_reset_connect(struct sock_xprt *transport)
 736{
 737	transport->recv.offset = 0;
 738	transport->recv.len = 0;
 739	transport->recv.copied = 0;
 740	transport->xmit.offset = 0;
 741}
 742
 743static void
 744xs_stream_start_connect(struct sock_xprt *transport)
 745{
 746	transport->xprt.stat.connect_count++;
 747	transport->xprt.stat.connect_start = jiffies;
 748}
 749
 750#define XS_SENDMSG_FLAGS	(MSG_DONTWAIT | MSG_NOSIGNAL)
 751
 752static int xs_sendmsg(struct socket *sock, struct msghdr *msg, size_t seek)
 753{
 754	if (seek)
 755		iov_iter_advance(&msg->msg_iter, seek);
 756	return sock_sendmsg(sock, msg);
 757}
 758
 759static int xs_send_kvec(struct socket *sock, struct msghdr *msg, struct kvec *vec, size_t seek)
 760{
 761	iov_iter_kvec(&msg->msg_iter, WRITE, vec, 1, vec->iov_len);
 762	return xs_sendmsg(sock, msg, seek);
 763}
 764
 765static int xs_send_pagedata(struct socket *sock, struct msghdr *msg, struct xdr_buf *xdr, size_t base)
 766{
 767	int err;
 768
 769	err = xdr_alloc_bvec(xdr, GFP_KERNEL);
 770	if (err < 0)
 771		return err;
 772
 773	iov_iter_bvec(&msg->msg_iter, WRITE, xdr->bvec,
 774			xdr_buf_pagecount(xdr),
 775			xdr->page_len + xdr->page_base);
 776	return xs_sendmsg(sock, msg, base + xdr->page_base);
 777}
 778
 779#define xs_record_marker_len() sizeof(rpc_fraghdr)
 780
 781/* Common case:
 782 *  - stream transport
 783 *  - sending from byte 0 of the message
 784 *  - the message is wholly contained in @xdr's head iovec
 785 */
 786static int xs_send_rm_and_kvec(struct socket *sock, struct msghdr *msg,
 787		rpc_fraghdr marker, struct kvec *vec, size_t base)
 788{
 789	struct kvec iov[2] = {
 790		[0] = {
 791			.iov_base	= &marker,
 792			.iov_len	= sizeof(marker)
 793		},
 794		[1] = *vec,
 795	};
 796	size_t len = iov[0].iov_len + iov[1].iov_len;
 797
 798	iov_iter_kvec(&msg->msg_iter, WRITE, iov, 2, len);
 799	return xs_sendmsg(sock, msg, base);
 800}
 801
 802/**
 803 * xs_sendpages - write pages directly to a socket
 804 * @sock: socket to send on
 805 * @addr: UDP only -- address of destination
 806 * @addrlen: UDP only -- length of destination address
 807 * @xdr: buffer containing this request
 808 * @base: starting position in the buffer
 809 * @rm: stream record marker field
 810 * @sent_p: return the total number of bytes successfully queued for sending
 811 *
 812 */
 813static int xs_sendpages(struct socket *sock, struct sockaddr *addr, int addrlen, struct xdr_buf *xdr, unsigned int base, rpc_fraghdr rm, int *sent_p)
 814{
 815	struct msghdr msg = {
 816		.msg_name = addr,
 817		.msg_namelen = addrlen,
 818		.msg_flags = XS_SENDMSG_FLAGS | MSG_MORE,
 819	};
 820	unsigned int rmsize = rm ? sizeof(rm) : 0;
 821	unsigned int remainder = rmsize + xdr->len - base;
 822	unsigned int want;
 823	int err = 0;
 824
 825	if (unlikely(!sock))
 826		return -ENOTSOCK;
 827
 828	want = xdr->head[0].iov_len + rmsize;
 829	if (base < want) {
 830		unsigned int len = want - base;
 831		remainder -= len;
 832		if (remainder == 0)
 833			msg.msg_flags &= ~MSG_MORE;
 834		if (rmsize)
 835			err = xs_send_rm_and_kvec(sock, &msg, rm,
 836					&xdr->head[0], base);
 837		else
 838			err = xs_send_kvec(sock, &msg, &xdr->head[0], base);
 839		if (remainder == 0 || err != len)
 840			goto out;
 841		*sent_p += err;
 842		base = 0;
 843	} else
 844		base -= want;
 845
 846	if (base < xdr->page_len) {
 847		unsigned int len = xdr->page_len - base;
 848		remainder -= len;
 849		if (remainder == 0)
 850			msg.msg_flags &= ~MSG_MORE;
 851		err = xs_send_pagedata(sock, &msg, xdr, base);
 852		if (remainder == 0 || err != len)
 853			goto out;
 854		*sent_p += err;
 855		base = 0;
 856	} else
 857		base -= xdr->page_len;
 858
 859	if (base >= xdr->tail[0].iov_len)
 860		return 0;
 861	msg.msg_flags &= ~MSG_MORE;
 862	err = xs_send_kvec(sock, &msg, &xdr->tail[0], base);
 863out:
 864	if (err > 0) {
 865		*sent_p += err;
 866		err = 0;
 867	}
 868	return err;
 869}
 870
 871/**
 872 * xs_nospace - handle transmit was incomplete
 873 * @req: pointer to RPC request
 874 *
 875 */
 876static int xs_nospace(struct rpc_rqst *req)
 877{
 878	struct rpc_xprt *xprt = req->rq_xprt;
 879	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 880	struct sock *sk = transport->inet;
 881	int ret = -EAGAIN;
 882
 883	dprintk("RPC: %5u xmit incomplete (%u left of %u)\n",
 884			req->rq_task->tk_pid,
 885			req->rq_slen - transport->xmit.offset,
 886			req->rq_slen);
 887
 888	/* Protect against races with write_space */
 889	spin_lock(&xprt->transport_lock);
 890
 891	/* Don't race with disconnect */
 892	if (xprt_connected(xprt)) {
 893		/* wait for more buffer space */
 894		sk->sk_write_pending++;
 895		xprt_wait_for_buffer_space(xprt);
 896	} else
 897		ret = -ENOTCONN;
 898
 899	spin_unlock(&xprt->transport_lock);
 900
 901	/* Race breaker in case memory is freed before above code is called */
 902	if (ret == -EAGAIN) {
 903		struct socket_wq *wq;
 904
 905		rcu_read_lock();
 906		wq = rcu_dereference(sk->sk_wq);
 907		set_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags);
 908		rcu_read_unlock();
 909
 910		sk->sk_write_space(sk);
 911	}
 912	return ret;
 913}
 914
 915static void
 916xs_stream_prepare_request(struct rpc_rqst *req)
 917{
 918	xdr_free_bvec(&req->rq_rcv_buf);
 919	req->rq_task->tk_status = xdr_alloc_bvec(&req->rq_rcv_buf, GFP_KERNEL);
 920}
 921
 922/*
 923 * Determine if the previous message in the stream was aborted before it
 924 * could complete transmission.
 925 */
 926static bool
 927xs_send_request_was_aborted(struct sock_xprt *transport, struct rpc_rqst *req)
 928{
 929	return transport->xmit.offset != 0 && req->rq_bytes_sent == 0;
 930}
 931
 932/*
 933 * Return the stream record marker field for a record of length < 2^31-1
 934 */
 935static rpc_fraghdr
 936xs_stream_record_marker(struct xdr_buf *xdr)
 937{
 938	if (!xdr->len)
 939		return 0;
 940	return cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | (u32)xdr->len);
 941}
 942
 943/**
 944 * xs_local_send_request - write an RPC request to an AF_LOCAL socket
 945 * @req: pointer to RPC request
 946 *
 947 * Return values:
 948 *        0:	The request has been sent
 949 *   EAGAIN:	The socket was blocked, please call again later to
 950 *		complete the request
 951 * ENOTCONN:	Caller needs to invoke connect logic then call again
 952 *    other:	Some other error occured, the request was not sent
 953 */
 954static int xs_local_send_request(struct rpc_rqst *req)
 955{
 956	struct rpc_xprt *xprt = req->rq_xprt;
 957	struct sock_xprt *transport =
 958				container_of(xprt, struct sock_xprt, xprt);
 959	struct xdr_buf *xdr = &req->rq_snd_buf;
 960	rpc_fraghdr rm = xs_stream_record_marker(xdr);
 961	unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
 
 
 
 
 962	int status;
 963	int sent = 0;
 964
 965	/* Close the stream if the previous transmission was incomplete */
 966	if (xs_send_request_was_aborted(transport, req)) {
 967		xs_close(xprt);
 968		return -ENOTCONN;
 969	}
 970
 971	xs_pktdump("packet data:",
 972			req->rq_svec->iov_base, req->rq_svec->iov_len);
 973
 974	req->rq_xtime = ktime_get();
 975	status = xs_sendpages(transport->sock, NULL, 0, xdr,
 976			      transport->xmit.offset, rm, &sent);
 977	dprintk("RPC:       %s(%u) = %d\n",
 978			__func__, xdr->len - transport->xmit.offset, status);
 979
 980	if (status == -EAGAIN && sock_writeable(transport->inet))
 981		status = -ENOBUFS;
 982
 983	if (likely(sent > 0) || status == 0) {
 984		transport->xmit.offset += sent;
 985		req->rq_bytes_sent = transport->xmit.offset;
 986		if (likely(req->rq_bytes_sent >= msglen)) {
 987			req->rq_xmit_bytes_sent += transport->xmit.offset;
 988			transport->xmit.offset = 0;
 989			return 0;
 990		}
 991		status = -EAGAIN;
 992	}
 993
 994	switch (status) {
 995	case -ENOBUFS:
 996		break;
 997	case -EAGAIN:
 998		status = xs_nospace(req);
 999		break;
1000	default:
1001		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1002			-status);
1003		/* fall through */
1004	case -EPIPE:
1005		xs_close(xprt);
1006		status = -ENOTCONN;
1007	}
1008
1009	return status;
1010}
1011
1012/**
1013 * xs_udp_send_request - write an RPC request to a UDP socket
1014 * @req: pointer to RPC request
1015 *
1016 * Return values:
1017 *        0:	The request has been sent
1018 *   EAGAIN:	The socket was blocked, please call again later to
1019 *		complete the request
1020 * ENOTCONN:	Caller needs to invoke connect logic then call again
1021 *    other:	Some other error occurred, the request was not sent
1022 */
1023static int xs_udp_send_request(struct rpc_rqst *req)
1024{
1025	struct rpc_xprt *xprt = req->rq_xprt;
1026	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1027	struct xdr_buf *xdr = &req->rq_snd_buf;
1028	int sent = 0;
 
 
 
 
 
1029	int status;
1030
1031	xs_pktdump("packet data:",
1032				req->rq_svec->iov_base,
1033				req->rq_svec->iov_len);
1034
1035	if (!xprt_bound(xprt))
1036		return -ENOTCONN;
1037
1038	if (!xprt_request_get_cong(xprt, req))
1039		return -EBADSLT;
1040
1041	req->rq_xtime = ktime_get();
1042	status = xs_sendpages(transport->sock, xs_addr(xprt), xprt->addrlen,
1043			      xdr, 0, 0, &sent);
1044
1045	dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
1046			xdr->len, status);
1047
1048	/* firewall is blocking us, don't return -EAGAIN or we end up looping */
1049	if (status == -EPERM)
1050		goto process_status;
1051
1052	if (status == -EAGAIN && sock_writeable(transport->inet))
1053		status = -ENOBUFS;
1054
1055	if (sent > 0 || status == 0) {
1056		req->rq_xmit_bytes_sent += sent;
1057		if (sent >= req->rq_slen)
1058			return 0;
1059		/* Still some bytes left; set up for a retry later. */
1060		status = -EAGAIN;
1061	}
1062
1063process_status:
1064	switch (status) {
1065	case -ENOTSOCK:
1066		status = -ENOTCONN;
1067		/* Should we call xs_close() here? */
1068		break;
1069	case -EAGAIN:
1070		status = xs_nospace(req);
1071		break;
1072	case -ENETUNREACH:
1073	case -ENOBUFS:
1074	case -EPIPE:
1075	case -ECONNREFUSED:
1076	case -EPERM:
1077		/* When the server has died, an ICMP port unreachable message
1078		 * prompts ECONNREFUSED. */
1079		break;
1080	default:
1081		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1082			-status);
1083	}
1084
1085	return status;
1086}
1087
1088/**
1089 * xs_tcp_send_request - write an RPC request to a TCP socket
1090 * @req: pointer to RPC request
1091 *
1092 * Return values:
1093 *        0:	The request has been sent
1094 *   EAGAIN:	The socket was blocked, please call again later to
1095 *		complete the request
1096 * ENOTCONN:	Caller needs to invoke connect logic then call again
1097 *    other:	Some other error occurred, the request was not sent
1098 *
1099 * XXX: In the case of soft timeouts, should we eventually give up
1100 *	if sendmsg is not able to make progress?
1101 */
1102static int xs_tcp_send_request(struct rpc_rqst *req)
1103{
1104	struct rpc_xprt *xprt = req->rq_xprt;
1105	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1106	struct xdr_buf *xdr = &req->rq_snd_buf;
1107	rpc_fraghdr rm = xs_stream_record_marker(xdr);
1108	unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
 
 
 
1109	bool vm_wait = false;
 
1110	int status;
1111	int sent;
1112
1113	/* Close the stream if the previous transmission was incomplete */
1114	if (xs_send_request_was_aborted(transport, req)) {
1115		if (transport->sock != NULL)
1116			kernel_sock_shutdown(transport->sock, SHUT_RDWR);
1117		return -ENOTCONN;
1118	}
1119
1120	xs_pktdump("packet data:",
1121				req->rq_svec->iov_base,
1122				req->rq_svec->iov_len);
1123
1124	if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state))
1125		xs_tcp_set_socket_timeouts(xprt, transport->sock);
1126
1127	/* Continue transmitting the packet/record. We must be careful
1128	 * to cope with writespace callbacks arriving _after_ we have
1129	 * called sendmsg(). */
1130	req->rq_xtime = ktime_get();
1131	while (1) {
1132		sent = 0;
1133		status = xs_sendpages(transport->sock, NULL, 0, xdr,
1134				      transport->xmit.offset, rm, &sent);
1135
1136		dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
1137				xdr->len - transport->xmit.offset, status);
1138
1139		/* If we've sent the entire packet, immediately
1140		 * reset the count of bytes sent. */
1141		transport->xmit.offset += sent;
1142		req->rq_bytes_sent = transport->xmit.offset;
1143		if (likely(req->rq_bytes_sent >= msglen)) {
1144			req->rq_xmit_bytes_sent += transport->xmit.offset;
1145			transport->xmit.offset = 0;
1146			return 0;
1147		}
1148
1149		WARN_ON_ONCE(sent == 0 && status == 0);
1150
1151		if (status == -EAGAIN ) {
1152			/*
1153			 * Return EAGAIN if we're sure we're hitting the
1154			 * socket send buffer limits.
1155			 */
1156			if (test_bit(SOCK_NOSPACE, &transport->sock->flags))
1157				break;
1158			/*
1159			 * Did we hit a memory allocation failure?
1160			 */
1161			if (sent == 0) {
1162				status = -ENOBUFS;
1163				if (vm_wait)
1164					break;
1165				/* Retry, knowing now that we're below the
1166				 * socket send buffer limit
1167				 */
1168				vm_wait = true;
1169			}
1170			continue;
1171		}
1172		if (status < 0)
1173			break;
1174		vm_wait = false;
1175	}
1176
1177	switch (status) {
1178	case -ENOTSOCK:
1179		status = -ENOTCONN;
1180		/* Should we call xs_close() here? */
1181		break;
1182	case -EAGAIN:
1183		status = xs_nospace(req);
1184		break;
1185	case -ECONNRESET:
1186	case -ECONNREFUSED:
1187	case -ENOTCONN:
1188	case -EADDRINUSE:
1189	case -ENOBUFS:
1190	case -EPIPE:
1191		break;
1192	default:
1193		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1194			-status);
1195	}
1196
1197	return status;
1198}
1199
1200static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1201{
1202	transport->old_data_ready = sk->sk_data_ready;
1203	transport->old_state_change = sk->sk_state_change;
1204	transport->old_write_space = sk->sk_write_space;
1205	transport->old_error_report = sk->sk_error_report;
1206}
1207
1208static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1209{
1210	sk->sk_data_ready = transport->old_data_ready;
1211	sk->sk_state_change = transport->old_state_change;
1212	sk->sk_write_space = transport->old_write_space;
1213	sk->sk_error_report = transport->old_error_report;
1214}
1215
1216static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
1217{
1218	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1219
1220	clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1221	clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state);
1222	clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state);
1223	clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state);
1224}
1225
1226static void xs_run_error_worker(struct sock_xprt *transport, unsigned int nr)
1227{
1228	set_bit(nr, &transport->sock_state);
1229	queue_work(xprtiod_workqueue, &transport->error_worker);
1230}
1231
1232static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
1233{
1234	smp_mb__before_atomic();
1235	clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1236	clear_bit(XPRT_CLOSING, &xprt->state);
1237	xs_sock_reset_state_flags(xprt);
1238	smp_mb__after_atomic();
1239}
1240
1241/**
1242 * xs_error_report - callback to handle TCP socket state errors
1243 * @sk: socket
1244 *
1245 * Note: we don't call sock_error() since there may be a rpc_task
1246 * using the socket, and so we don't want to clear sk->sk_err.
1247 */
1248static void xs_error_report(struct sock *sk)
1249{
1250	struct sock_xprt *transport;
1251	struct rpc_xprt *xprt;
1252
1253	read_lock_bh(&sk->sk_callback_lock);
1254	if (!(xprt = xprt_from_sock(sk)))
1255		goto out;
1256
1257	transport = container_of(xprt, struct sock_xprt, xprt);
1258	transport->xprt_err = -sk->sk_err;
1259	if (transport->xprt_err == 0)
1260		goto out;
1261	dprintk("RPC:       xs_error_report client %p, error=%d...\n",
1262			xprt, -transport->xprt_err);
1263	trace_rpc_socket_error(xprt, sk->sk_socket, transport->xprt_err);
1264
1265	/* barrier ensures xprt_err is set before XPRT_SOCK_WAKE_ERROR */
1266	smp_mb__before_atomic();
1267	xs_run_error_worker(transport, XPRT_SOCK_WAKE_ERROR);
1268 out:
1269	read_unlock_bh(&sk->sk_callback_lock);
1270}
1271
1272static void xs_reset_transport(struct sock_xprt *transport)
1273{
1274	struct socket *sock = transport->sock;
1275	struct sock *sk = transport->inet;
1276	struct rpc_xprt *xprt = &transport->xprt;
1277	struct file *filp = transport->file;
1278
1279	if (sk == NULL)
1280		return;
1281
1282	if (atomic_read(&transport->xprt.swapper))
1283		sk_clear_memalloc(sk);
1284
1285	kernel_sock_shutdown(sock, SHUT_RDWR);
1286
1287	mutex_lock(&transport->recv_mutex);
1288	write_lock_bh(&sk->sk_callback_lock);
1289	transport->inet = NULL;
1290	transport->sock = NULL;
1291	transport->file = NULL;
1292
1293	sk->sk_user_data = NULL;
1294
1295	xs_restore_old_callbacks(transport, sk);
1296	xprt_clear_connected(xprt);
1297	write_unlock_bh(&sk->sk_callback_lock);
1298	xs_sock_reset_connection_flags(xprt);
1299	/* Reset stream record info */
1300	xs_stream_reset_connect(transport);
1301	mutex_unlock(&transport->recv_mutex);
1302
1303	trace_rpc_socket_close(xprt, sock);
1304	fput(filp);
1305
1306	xprt_disconnect_done(xprt);
1307}
1308
1309/**
1310 * xs_close - close a socket
1311 * @xprt: transport
1312 *
1313 * This is used when all requests are complete; ie, no DRC state remains
1314 * on the server we want to save.
1315 *
1316 * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
1317 * xs_reset_transport() zeroing the socket from underneath a writer.
1318 */
1319static void xs_close(struct rpc_xprt *xprt)
1320{
1321	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1322
1323	dprintk("RPC:       xs_close xprt %p\n", xprt);
1324
1325	xs_reset_transport(transport);
1326	xprt->reestablish_timeout = 0;
1327}
1328
1329static void xs_inject_disconnect(struct rpc_xprt *xprt)
1330{
1331	dprintk("RPC:       injecting transport disconnect on xprt=%p\n",
1332		xprt);
1333	xprt_disconnect_done(xprt);
1334}
1335
1336static void xs_xprt_free(struct rpc_xprt *xprt)
1337{
1338	xs_free_peer_addresses(xprt);
1339	xprt_free(xprt);
1340}
1341
1342/**
1343 * xs_destroy - prepare to shutdown a transport
1344 * @xprt: doomed transport
1345 *
1346 */
1347static void xs_destroy(struct rpc_xprt *xprt)
1348{
1349	struct sock_xprt *transport = container_of(xprt,
1350			struct sock_xprt, xprt);
1351	dprintk("RPC:       xs_destroy xprt %p\n", xprt);
1352
1353	cancel_delayed_work_sync(&transport->connect_worker);
1354	xs_close(xprt);
1355	cancel_work_sync(&transport->recv_worker);
1356	cancel_work_sync(&transport->error_worker);
1357	xs_xprt_free(xprt);
1358	module_put(THIS_MODULE);
1359}
1360
1361/**
1362 * xs_udp_data_read_skb - receive callback for UDP sockets
1363 * @xprt: transport
1364 * @sk: socket
1365 * @skb: skbuff
1366 *
1367 */
1368static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
1369		struct sock *sk,
1370		struct sk_buff *skb)
1371{
1372	struct rpc_task *task;
1373	struct rpc_rqst *rovr;
1374	int repsize, copied;
1375	u32 _xid;
1376	__be32 *xp;
1377
1378	repsize = skb->len;
1379	if (repsize < 4) {
1380		dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
1381		return;
1382	}
1383
1384	/* Copy the XID from the skb... */
1385	xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
1386	if (xp == NULL)
1387		return;
1388
1389	/* Look up and lock the request corresponding to the given XID */
1390	spin_lock(&xprt->queue_lock);
1391	rovr = xprt_lookup_rqst(xprt, *xp);
1392	if (!rovr)
1393		goto out_unlock;
1394	xprt_pin_rqst(rovr);
1395	xprt_update_rtt(rovr->rq_task);
1396	spin_unlock(&xprt->queue_lock);
1397	task = rovr->rq_task;
1398
1399	if ((copied = rovr->rq_private_buf.buflen) > repsize)
1400		copied = repsize;
1401
1402	/* Suck it into the iovec, verify checksum if not done by hw. */
1403	if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1404		spin_lock(&xprt->queue_lock);
1405		__UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
1406		goto out_unpin;
1407	}
1408
1409
1410	spin_lock(&xprt->transport_lock);
1411	xprt_adjust_cwnd(xprt, task, copied);
1412	spin_unlock(&xprt->transport_lock);
1413	spin_lock(&xprt->queue_lock);
1414	xprt_complete_rqst(task, copied);
1415	__UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
1416out_unpin:
1417	xprt_unpin_rqst(rovr);
1418 out_unlock:
1419	spin_unlock(&xprt->queue_lock);
1420}
1421
1422static void xs_udp_data_receive(struct sock_xprt *transport)
1423{
1424	struct sk_buff *skb;
1425	struct sock *sk;
1426	int err;
1427
1428	mutex_lock(&transport->recv_mutex);
1429	sk = transport->inet;
1430	if (sk == NULL)
1431		goto out;
1432	for (;;) {
1433		skb = skb_recv_udp(sk, 0, 1, &err);
1434		if (skb == NULL)
1435			break;
1436		xs_udp_data_read_skb(&transport->xprt, sk, skb);
1437		consume_skb(skb);
1438		cond_resched();
1439	}
1440	xs_poll_check_readable(transport);
1441out:
1442	mutex_unlock(&transport->recv_mutex);
1443}
1444
1445static void xs_udp_data_receive_workfn(struct work_struct *work)
1446{
1447	struct sock_xprt *transport =
1448		container_of(work, struct sock_xprt, recv_worker);
1449	unsigned int pflags = memalloc_nofs_save();
1450
1451	xs_udp_data_receive(transport);
1452	memalloc_nofs_restore(pflags);
1453}
1454
1455/**
1456 * xs_data_ready - "data ready" callback for UDP sockets
1457 * @sk: socket with data to read
1458 *
1459 */
1460static void xs_data_ready(struct sock *sk)
1461{
1462	struct rpc_xprt *xprt;
1463
1464	read_lock_bh(&sk->sk_callback_lock);
1465	dprintk("RPC:       xs_data_ready...\n");
1466	xprt = xprt_from_sock(sk);
1467	if (xprt != NULL) {
1468		struct sock_xprt *transport = container_of(xprt,
1469				struct sock_xprt, xprt);
1470		transport->old_data_ready(sk);
1471		/* Any data means we had a useful conversation, so
1472		 * then we don't need to delay the next reconnect
1473		 */
1474		if (xprt->reestablish_timeout)
1475			xprt->reestablish_timeout = 0;
1476		if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1477			queue_work(xprtiod_workqueue, &transport->recv_worker);
1478	}
1479	read_unlock_bh(&sk->sk_callback_lock);
1480}
1481
1482/*
1483 * Helper function to force a TCP close if the server is sending
1484 * junk and/or it has put us in CLOSE_WAIT
1485 */
1486static void xs_tcp_force_close(struct rpc_xprt *xprt)
1487{
1488	xprt_force_disconnect(xprt);
1489}
1490
1491#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1492static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
1493{
1494	return PAGE_SIZE;
1495}
1496#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1497
1498/**
1499 * xs_tcp_state_change - callback to handle TCP socket state changes
1500 * @sk: socket whose state has changed
1501 *
1502 */
1503static void xs_tcp_state_change(struct sock *sk)
1504{
1505	struct rpc_xprt *xprt;
1506	struct sock_xprt *transport;
1507
1508	read_lock_bh(&sk->sk_callback_lock);
1509	if (!(xprt = xprt_from_sock(sk)))
1510		goto out;
1511	dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1512	dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1513			sk->sk_state, xprt_connected(xprt),
1514			sock_flag(sk, SOCK_DEAD),
1515			sock_flag(sk, SOCK_ZAPPED),
1516			sk->sk_shutdown);
1517
1518	transport = container_of(xprt, struct sock_xprt, xprt);
1519	trace_rpc_socket_state_change(xprt, sk->sk_socket);
1520	switch (sk->sk_state) {
1521	case TCP_ESTABLISHED:
1522		if (!xprt_test_and_set_connected(xprt)) {
1523			xprt->connect_cookie++;
1524			clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
1525			xprt_clear_connecting(xprt);
1526
1527			xprt->stat.connect_count++;
1528			xprt->stat.connect_time += (long)jiffies -
1529						   xprt->stat.connect_start;
1530			xs_run_error_worker(transport, XPRT_SOCK_WAKE_PENDING);
1531		}
1532		break;
1533	case TCP_FIN_WAIT1:
1534		/* The client initiated a shutdown of the socket */
1535		xprt->connect_cookie++;
1536		xprt->reestablish_timeout = 0;
1537		set_bit(XPRT_CLOSING, &xprt->state);
1538		smp_mb__before_atomic();
1539		clear_bit(XPRT_CONNECTED, &xprt->state);
1540		clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1541		smp_mb__after_atomic();
1542		break;
1543	case TCP_CLOSE_WAIT:
1544		/* The server initiated a shutdown of the socket */
1545		xprt->connect_cookie++;
1546		clear_bit(XPRT_CONNECTED, &xprt->state);
1547		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1548		/* fall through */
1549	case TCP_CLOSING:
1550		/*
1551		 * If the server closed down the connection, make sure that
1552		 * we back off before reconnecting
1553		 */
1554		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1555			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1556		break;
1557	case TCP_LAST_ACK:
1558		set_bit(XPRT_CLOSING, &xprt->state);
1559		smp_mb__before_atomic();
1560		clear_bit(XPRT_CONNECTED, &xprt->state);
1561		smp_mb__after_atomic();
1562		break;
1563	case TCP_CLOSE:
1564		if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
1565					&transport->sock_state))
1566			xprt_clear_connecting(xprt);
1567		clear_bit(XPRT_CLOSING, &xprt->state);
1568		/* Trigger the socket release */
1569		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1570	}
1571 out:
1572	read_unlock_bh(&sk->sk_callback_lock);
1573}
1574
1575static void xs_write_space(struct sock *sk)
1576{
1577	struct socket_wq *wq;
1578	struct sock_xprt *transport;
1579	struct rpc_xprt *xprt;
1580
1581	if (!sk->sk_socket)
1582		return;
1583	clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1584
1585	if (unlikely(!(xprt = xprt_from_sock(sk))))
1586		return;
1587	transport = container_of(xprt, struct sock_xprt, xprt);
1588	rcu_read_lock();
1589	wq = rcu_dereference(sk->sk_wq);
1590	if (!wq || test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags) == 0)
1591		goto out;
1592
1593	xs_run_error_worker(transport, XPRT_SOCK_WAKE_WRITE);
1594	sk->sk_write_pending--;
1595out:
1596	rcu_read_unlock();
1597}
1598
1599/**
1600 * xs_udp_write_space - callback invoked when socket buffer space
1601 *                             becomes available
1602 * @sk: socket whose state has changed
1603 *
1604 * Called when more output buffer space is available for this socket.
1605 * We try not to wake our writers until they can make "significant"
1606 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1607 * with a bunch of small requests.
1608 */
1609static void xs_udp_write_space(struct sock *sk)
1610{
1611	read_lock_bh(&sk->sk_callback_lock);
1612
1613	/* from net/core/sock.c:sock_def_write_space */
1614	if (sock_writeable(sk))
1615		xs_write_space(sk);
1616
1617	read_unlock_bh(&sk->sk_callback_lock);
1618}
1619
1620/**
1621 * xs_tcp_write_space - callback invoked when socket buffer space
1622 *                             becomes available
1623 * @sk: socket whose state has changed
1624 *
1625 * Called when more output buffer space is available for this socket.
1626 * We try not to wake our writers until they can make "significant"
1627 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1628 * with a bunch of small requests.
1629 */
1630static void xs_tcp_write_space(struct sock *sk)
1631{
1632	read_lock_bh(&sk->sk_callback_lock);
1633
1634	/* from net/core/stream.c:sk_stream_write_space */
1635	if (sk_stream_is_writeable(sk))
1636		xs_write_space(sk);
1637
1638	read_unlock_bh(&sk->sk_callback_lock);
1639}
1640
1641static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1642{
1643	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1644	struct sock *sk = transport->inet;
1645
1646	if (transport->rcvsize) {
1647		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1648		sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1649	}
1650	if (transport->sndsize) {
1651		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1652		sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1653		sk->sk_write_space(sk);
1654	}
1655}
1656
1657/**
1658 * xs_udp_set_buffer_size - set send and receive limits
1659 * @xprt: generic transport
1660 * @sndsize: requested size of send buffer, in bytes
1661 * @rcvsize: requested size of receive buffer, in bytes
1662 *
1663 * Set socket send and receive buffer size limits.
1664 */
1665static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1666{
1667	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1668
1669	transport->sndsize = 0;
1670	if (sndsize)
1671		transport->sndsize = sndsize + 1024;
1672	transport->rcvsize = 0;
1673	if (rcvsize)
1674		transport->rcvsize = rcvsize + 1024;
1675
1676	xs_udp_do_set_buffer_size(xprt);
1677}
1678
1679/**
1680 * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1681 * @xprt: controlling transport
1682 * @task: task that timed out
1683 *
1684 * Adjust the congestion window after a retransmit timeout has occurred.
1685 */
1686static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1687{
1688	spin_lock(&xprt->transport_lock);
1689	xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1690	spin_unlock(&xprt->transport_lock);
1691}
1692
1693static int xs_get_random_port(void)
1694{
1695	unsigned short min = xprt_min_resvport, max = xprt_max_resvport;
1696	unsigned short range;
1697	unsigned short rand;
1698
1699	if (max < min)
1700		return -EADDRINUSE;
1701	range = max - min + 1;
1702	rand = (unsigned short) prandom_u32() % range;
1703	return rand + min;
1704}
1705
1706/**
1707 * xs_set_reuseaddr_port - set the socket's port and address reuse options
1708 * @sock: socket
1709 *
1710 * Note that this function has to be called on all sockets that share the
1711 * same port, and it must be called before binding.
1712 */
1713static void xs_sock_set_reuseport(struct socket *sock)
1714{
1715	int opt = 1;
1716
1717	kernel_setsockopt(sock, SOL_SOCKET, SO_REUSEPORT,
1718			(char *)&opt, sizeof(opt));
1719}
1720
1721static unsigned short xs_sock_getport(struct socket *sock)
1722{
1723	struct sockaddr_storage buf;
1724	unsigned short port = 0;
1725
1726	if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0)
1727		goto out;
1728	switch (buf.ss_family) {
1729	case AF_INET6:
1730		port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1731		break;
1732	case AF_INET:
1733		port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1734	}
1735out:
1736	return port;
1737}
1738
1739/**
1740 * xs_set_port - reset the port number in the remote endpoint address
1741 * @xprt: generic transport
1742 * @port: new port number
1743 *
1744 */
1745static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1746{
1747	dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1748
1749	rpc_set_port(xs_addr(xprt), port);
1750	xs_update_peer_port(xprt);
1751}
1752
1753static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1754{
1755	if (transport->srcport == 0)
1756		transport->srcport = xs_sock_getport(sock);
1757}
1758
1759static int xs_get_srcport(struct sock_xprt *transport)
1760{
1761	int port = transport->srcport;
1762
1763	if (port == 0 && transport->xprt.resvport)
1764		port = xs_get_random_port();
1765	return port;
1766}
1767
1768static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1769{
1770	if (transport->srcport != 0)
1771		transport->srcport = 0;
1772	if (!transport->xprt.resvport)
1773		return 0;
1774	if (port <= xprt_min_resvport || port > xprt_max_resvport)
1775		return xprt_max_resvport;
1776	return --port;
1777}
1778static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1779{
1780	struct sockaddr_storage myaddr;
1781	int err, nloop = 0;
1782	int port = xs_get_srcport(transport);
1783	unsigned short last;
1784
1785	/*
1786	 * If we are asking for any ephemeral port (i.e. port == 0 &&
1787	 * transport->xprt.resvport == 0), don't bind.  Let the local
1788	 * port selection happen implicitly when the socket is used
1789	 * (for example at connect time).
1790	 *
1791	 * This ensures that we can continue to establish TCP
1792	 * connections even when all local ephemeral ports are already
1793	 * a part of some TCP connection.  This makes no difference
1794	 * for UDP sockets, but also doens't harm them.
1795	 *
1796	 * If we're asking for any reserved port (i.e. port == 0 &&
1797	 * transport->xprt.resvport == 1) xs_get_srcport above will
1798	 * ensure that port is non-zero and we will bind as needed.
1799	 */
1800	if (port <= 0)
1801		return port;
1802
1803	memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1804	do {
1805		rpc_set_port((struct sockaddr *)&myaddr, port);
1806		err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1807				transport->xprt.addrlen);
1808		if (err == 0) {
1809			transport->srcport = port;
1810			break;
1811		}
1812		last = port;
1813		port = xs_next_srcport(transport, port);
1814		if (port > last)
1815			nloop++;
1816	} while (err == -EADDRINUSE && nloop != 2);
1817
1818	if (myaddr.ss_family == AF_INET)
1819		dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1820				&((struct sockaddr_in *)&myaddr)->sin_addr,
1821				port, err ? "failed" : "ok", err);
1822	else
1823		dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1824				&((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1825				port, err ? "failed" : "ok", err);
1826	return err;
1827}
1828
1829/*
1830 * We don't support autobind on AF_LOCAL sockets
1831 */
1832static void xs_local_rpcbind(struct rpc_task *task)
1833{
1834	xprt_set_bound(task->tk_xprt);
1835}
1836
1837static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1838{
1839}
1840
1841#ifdef CONFIG_DEBUG_LOCK_ALLOC
1842static struct lock_class_key xs_key[2];
1843static struct lock_class_key xs_slock_key[2];
1844
1845static inline void xs_reclassify_socketu(struct socket *sock)
1846{
1847	struct sock *sk = sock->sk;
1848
1849	sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1850		&xs_slock_key[1], "sk_lock-AF_LOCAL-RPC", &xs_key[1]);
1851}
1852
1853static inline void xs_reclassify_socket4(struct socket *sock)
1854{
1855	struct sock *sk = sock->sk;
1856
1857	sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1858		&xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1859}
1860
1861static inline void xs_reclassify_socket6(struct socket *sock)
1862{
1863	struct sock *sk = sock->sk;
1864
1865	sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1866		&xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1867}
1868
1869static inline void xs_reclassify_socket(int family, struct socket *sock)
1870{
1871	if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
1872		return;
1873
1874	switch (family) {
1875	case AF_LOCAL:
1876		xs_reclassify_socketu(sock);
1877		break;
1878	case AF_INET:
1879		xs_reclassify_socket4(sock);
1880		break;
1881	case AF_INET6:
1882		xs_reclassify_socket6(sock);
1883		break;
1884	}
1885}
1886#else
1887static inline void xs_reclassify_socket(int family, struct socket *sock)
1888{
1889}
1890#endif
1891
1892static void xs_dummy_setup_socket(struct work_struct *work)
1893{
1894}
1895
1896static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1897		struct sock_xprt *transport, int family, int type,
1898		int protocol, bool reuseport)
1899{
1900	struct file *filp;
1901	struct socket *sock;
1902	int err;
1903
1904	err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1905	if (err < 0) {
1906		dprintk("RPC:       can't create %d transport socket (%d).\n",
1907				protocol, -err);
1908		goto out;
1909	}
1910	xs_reclassify_socket(family, sock);
1911
1912	if (reuseport)
1913		xs_sock_set_reuseport(sock);
1914
1915	err = xs_bind(transport, sock);
1916	if (err) {
1917		sock_release(sock);
1918		goto out;
1919	}
1920
1921	filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1922	if (IS_ERR(filp))
1923		return ERR_CAST(filp);
1924	transport->file = filp;
1925
1926	return sock;
1927out:
1928	return ERR_PTR(err);
1929}
1930
1931static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1932				      struct socket *sock)
1933{
1934	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1935									xprt);
1936
1937	if (!transport->inet) {
1938		struct sock *sk = sock->sk;
1939
1940		write_lock_bh(&sk->sk_callback_lock);
1941
1942		xs_save_old_callbacks(transport, sk);
1943
1944		sk->sk_user_data = xprt;
1945		sk->sk_data_ready = xs_data_ready;
1946		sk->sk_write_space = xs_udp_write_space;
1947		sock_set_flag(sk, SOCK_FASYNC);
1948		sk->sk_error_report = xs_error_report;
1949
1950		xprt_clear_connected(xprt);
1951
1952		/* Reset to new socket */
1953		transport->sock = sock;
1954		transport->inet = sk;
1955
1956		write_unlock_bh(&sk->sk_callback_lock);
1957	}
1958
1959	xs_stream_start_connect(transport);
1960
1961	return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1962}
1963
1964/**
1965 * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1966 * @transport: socket transport to connect
1967 */
1968static int xs_local_setup_socket(struct sock_xprt *transport)
1969{
1970	struct rpc_xprt *xprt = &transport->xprt;
1971	struct file *filp;
1972	struct socket *sock;
1973	int status = -EIO;
1974
1975	status = __sock_create(xprt->xprt_net, AF_LOCAL,
1976					SOCK_STREAM, 0, &sock, 1);
1977	if (status < 0) {
1978		dprintk("RPC:       can't create AF_LOCAL "
1979			"transport socket (%d).\n", -status);
1980		goto out;
1981	}
1982	xs_reclassify_socket(AF_LOCAL, sock);
1983
1984	filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1985	if (IS_ERR(filp)) {
1986		status = PTR_ERR(filp);
1987		goto out;
1988	}
1989	transport->file = filp;
1990
1991	dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
1992			xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1993
1994	status = xs_local_finish_connecting(xprt, sock);
1995	trace_rpc_socket_connect(xprt, sock, status);
1996	switch (status) {
1997	case 0:
1998		dprintk("RPC:       xprt %p connected to %s\n",
1999				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2000		xprt->stat.connect_count++;
2001		xprt->stat.connect_time += (long)jiffies -
2002					   xprt->stat.connect_start;
2003		xprt_set_connected(xprt);
2004	case -ENOBUFS:
2005		break;
2006	case -ENOENT:
2007		dprintk("RPC:       xprt %p: socket %s does not exist\n",
2008				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2009		break;
2010	case -ECONNREFUSED:
2011		dprintk("RPC:       xprt %p: connection refused for %s\n",
2012				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2013		break;
2014	default:
2015		printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
2016				__func__, -status,
2017				xprt->address_strings[RPC_DISPLAY_ADDR]);
2018	}
2019
2020out:
2021	xprt_clear_connecting(xprt);
2022	xprt_wake_pending_tasks(xprt, status);
2023	return status;
2024}
2025
2026static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2027{
2028	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2029	int ret;
2030
2031	 if (RPC_IS_ASYNC(task)) {
2032		/*
2033		 * We want the AF_LOCAL connect to be resolved in the
2034		 * filesystem namespace of the process making the rpc
2035		 * call.  Thus we connect synchronously.
2036		 *
2037		 * If we want to support asynchronous AF_LOCAL calls,
2038		 * we'll need to figure out how to pass a namespace to
2039		 * connect.
2040		 */
2041		task->tk_rpc_status = -ENOTCONN;
2042		rpc_exit(task, -ENOTCONN);
2043		return;
2044	}
2045	ret = xs_local_setup_socket(transport);
2046	if (ret && !RPC_IS_SOFTCONN(task))
2047		msleep_interruptible(15000);
2048}
2049
2050#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
2051/*
2052 * Note that this should be called with XPRT_LOCKED held (or when we otherwise
2053 * know that we have exclusive access to the socket), to guard against
2054 * races with xs_reset_transport.
2055 */
2056static void xs_set_memalloc(struct rpc_xprt *xprt)
2057{
2058	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
2059			xprt);
2060
2061	/*
2062	 * If there's no sock, then we have nothing to set. The
2063	 * reconnecting process will get it for us.
2064	 */
2065	if (!transport->inet)
2066		return;
2067	if (atomic_read(&xprt->swapper))
2068		sk_set_memalloc(transport->inet);
2069}
2070
2071/**
2072 * xs_enable_swap - Tag this transport as being used for swap.
2073 * @xprt: transport to tag
2074 *
2075 * Take a reference to this transport on behalf of the rpc_clnt, and
2076 * optionally mark it for swapping if it wasn't already.
2077 */
2078static int
2079xs_enable_swap(struct rpc_xprt *xprt)
2080{
2081	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2082
2083	if (atomic_inc_return(&xprt->swapper) != 1)
2084		return 0;
2085	if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2086		return -ERESTARTSYS;
2087	if (xs->inet)
2088		sk_set_memalloc(xs->inet);
2089	xprt_release_xprt(xprt, NULL);
2090	return 0;
2091}
2092
2093/**
2094 * xs_disable_swap - Untag this transport as being used for swap.
2095 * @xprt: transport to tag
2096 *
2097 * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
2098 * swapper refcount goes to 0, untag the socket as a memalloc socket.
2099 */
2100static void
2101xs_disable_swap(struct rpc_xprt *xprt)
2102{
2103	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2104
2105	if (!atomic_dec_and_test(&xprt->swapper))
2106		return;
2107	if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2108		return;
2109	if (xs->inet)
2110		sk_clear_memalloc(xs->inet);
2111	xprt_release_xprt(xprt, NULL);
2112}
2113#else
2114static void xs_set_memalloc(struct rpc_xprt *xprt)
2115{
2116}
2117
2118static int
2119xs_enable_swap(struct rpc_xprt *xprt)
2120{
2121	return -EINVAL;
2122}
2123
2124static void
2125xs_disable_swap(struct rpc_xprt *xprt)
2126{
2127}
2128#endif
2129
2130static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2131{
2132	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2133
2134	if (!transport->inet) {
2135		struct sock *sk = sock->sk;
2136
2137		write_lock_bh(&sk->sk_callback_lock);
2138
2139		xs_save_old_callbacks(transport, sk);
2140
2141		sk->sk_user_data = xprt;
2142		sk->sk_data_ready = xs_data_ready;
2143		sk->sk_write_space = xs_udp_write_space;
2144		sock_set_flag(sk, SOCK_FASYNC);
2145
2146		xprt_set_connected(xprt);
2147
2148		/* Reset to new socket */
2149		transport->sock = sock;
2150		transport->inet = sk;
2151
2152		xs_set_memalloc(xprt);
2153
2154		write_unlock_bh(&sk->sk_callback_lock);
2155	}
2156	xs_udp_do_set_buffer_size(xprt);
2157
2158	xprt->stat.connect_start = jiffies;
2159}
2160
2161static void xs_udp_setup_socket(struct work_struct *work)
2162{
2163	struct sock_xprt *transport =
2164		container_of(work, struct sock_xprt, connect_worker.work);
2165	struct rpc_xprt *xprt = &transport->xprt;
2166	struct socket *sock;
2167	int status = -EIO;
2168
2169	sock = xs_create_sock(xprt, transport,
2170			xs_addr(xprt)->sa_family, SOCK_DGRAM,
2171			IPPROTO_UDP, false);
2172	if (IS_ERR(sock))
2173		goto out;
2174
2175	dprintk("RPC:       worker connecting xprt %p via %s to "
2176				"%s (port %s)\n", xprt,
2177			xprt->address_strings[RPC_DISPLAY_PROTO],
2178			xprt->address_strings[RPC_DISPLAY_ADDR],
2179			xprt->address_strings[RPC_DISPLAY_PORT]);
2180
2181	xs_udp_finish_connecting(xprt, sock);
2182	trace_rpc_socket_connect(xprt, sock, 0);
2183	status = 0;
2184out:
2185	xprt_clear_connecting(xprt);
2186	xprt_unlock_connect(xprt, transport);
2187	xprt_wake_pending_tasks(xprt, status);
2188}
2189
2190/**
2191 * xs_tcp_shutdown - gracefully shut down a TCP socket
2192 * @xprt: transport
2193 *
2194 * Initiates a graceful shutdown of the TCP socket by calling the
2195 * equivalent of shutdown(SHUT_RDWR);
2196 */
2197static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2198{
2199	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2200	struct socket *sock = transport->sock;
2201	int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
2202
2203	if (sock == NULL)
2204		return;
2205	switch (skst) {
2206	default:
2207		kernel_sock_shutdown(sock, SHUT_RDWR);
2208		trace_rpc_socket_shutdown(xprt, sock);
2209		break;
2210	case TCP_CLOSE:
2211	case TCP_TIME_WAIT:
2212		xs_reset_transport(transport);
2213	}
2214}
2215
2216static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
2217		struct socket *sock)
2218{
2219	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2220	unsigned int keepidle;
2221	unsigned int keepcnt;
2222	unsigned int opt_on = 1;
2223	unsigned int timeo;
2224
2225	spin_lock(&xprt->transport_lock);
2226	keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
2227	keepcnt = xprt->timeout->to_retries + 1;
2228	timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2229		(xprt->timeout->to_retries + 1);
2230	clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2231	spin_unlock(&xprt->transport_lock);
2232
2233	/* TCP Keepalive options */
2234	kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
2235			(char *)&opt_on, sizeof(opt_on));
2236	kernel_setsockopt(sock, SOL_TCP, TCP_KEEPIDLE,
2237			(char *)&keepidle, sizeof(keepidle));
2238	kernel_setsockopt(sock, SOL_TCP, TCP_KEEPINTVL,
2239			(char *)&keepidle, sizeof(keepidle));
2240	kernel_setsockopt(sock, SOL_TCP, TCP_KEEPCNT,
2241			(char *)&keepcnt, sizeof(keepcnt));
2242
2243	/* TCP user timeout (see RFC5482) */
2244	kernel_setsockopt(sock, SOL_TCP, TCP_USER_TIMEOUT,
2245			(char *)&timeo, sizeof(timeo));
2246}
2247
2248static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
2249		unsigned long connect_timeout,
2250		unsigned long reconnect_timeout)
2251{
2252	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2253	struct rpc_timeout to;
2254	unsigned long initval;
2255
2256	spin_lock(&xprt->transport_lock);
2257	if (reconnect_timeout < xprt->max_reconnect_timeout)
2258		xprt->max_reconnect_timeout = reconnect_timeout;
2259	if (connect_timeout < xprt->connect_timeout) {
2260		memcpy(&to, xprt->timeout, sizeof(to));
2261		initval = DIV_ROUND_UP(connect_timeout, to.to_retries + 1);
2262		/* Arbitrary lower limit */
2263		if (initval <  XS_TCP_INIT_REEST_TO << 1)
2264			initval = XS_TCP_INIT_REEST_TO << 1;
2265		to.to_initval = initval;
2266		to.to_maxval = initval;
2267		memcpy(&transport->tcp_timeout, &to,
2268				sizeof(transport->tcp_timeout));
2269		xprt->timeout = &transport->tcp_timeout;
2270		xprt->connect_timeout = connect_timeout;
2271	}
2272	set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2273	spin_unlock(&xprt->transport_lock);
2274}
2275
2276static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2277{
2278	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2279	int ret = -ENOTCONN;
2280
2281	if (!transport->inet) {
2282		struct sock *sk = sock->sk;
2283		unsigned int addr_pref = IPV6_PREFER_SRC_PUBLIC;
2284
2285		/* Avoid temporary address, they are bad for long-lived
2286		 * connections such as NFS mounts.
2287		 * RFC4941, section 3.6 suggests that:
2288		 *    Individual applications, which have specific
2289		 *    knowledge about the normal duration of connections,
2290		 *    MAY override this as appropriate.
2291		 */
2292		kernel_setsockopt(sock, SOL_IPV6, IPV6_ADDR_PREFERENCES,
2293				(char *)&addr_pref, sizeof(addr_pref));
 
 
2294
2295		xs_tcp_set_socket_timeouts(xprt, sock);
2296
2297		write_lock_bh(&sk->sk_callback_lock);
2298
2299		xs_save_old_callbacks(transport, sk);
2300
2301		sk->sk_user_data = xprt;
2302		sk->sk_data_ready = xs_data_ready;
2303		sk->sk_state_change = xs_tcp_state_change;
2304		sk->sk_write_space = xs_tcp_write_space;
2305		sock_set_flag(sk, SOCK_FASYNC);
2306		sk->sk_error_report = xs_error_report;
2307
2308		/* socket options */
2309		sock_reset_flag(sk, SOCK_LINGER);
2310		tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
2311
2312		xprt_clear_connected(xprt);
2313
2314		/* Reset to new socket */
2315		transport->sock = sock;
2316		transport->inet = sk;
2317
2318		write_unlock_bh(&sk->sk_callback_lock);
2319	}
2320
2321	if (!xprt_bound(xprt))
2322		goto out;
2323
2324	xs_set_memalloc(xprt);
2325
2326	xs_stream_start_connect(transport);
2327
2328	/* Tell the socket layer to start connecting... */
2329	set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2330	ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2331	switch (ret) {
2332	case 0:
2333		xs_set_srcport(transport, sock);
2334		/* fall through */
2335	case -EINPROGRESS:
2336		/* SYN_SENT! */
2337		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2338			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2339		break;
2340	case -EADDRNOTAVAIL:
2341		/* Source port number is unavailable. Try a new one! */
2342		transport->srcport = 0;
2343	}
2344out:
2345	return ret;
2346}
2347
2348/**
2349 * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2350 * @work: queued work item
2351 *
2352 * Invoked by a work queue tasklet.
2353 */
2354static void xs_tcp_setup_socket(struct work_struct *work)
2355{
2356	struct sock_xprt *transport =
2357		container_of(work, struct sock_xprt, connect_worker.work);
2358	struct socket *sock = transport->sock;
2359	struct rpc_xprt *xprt = &transport->xprt;
2360	int status = -EIO;
2361
2362	if (!sock) {
2363		sock = xs_create_sock(xprt, transport,
2364				xs_addr(xprt)->sa_family, SOCK_STREAM,
2365				IPPROTO_TCP, true);
2366		if (IS_ERR(sock)) {
2367			status = PTR_ERR(sock);
2368			goto out;
2369		}
2370	}
2371
2372	dprintk("RPC:       worker connecting xprt %p via %s to "
2373				"%s (port %s)\n", xprt,
2374			xprt->address_strings[RPC_DISPLAY_PROTO],
2375			xprt->address_strings[RPC_DISPLAY_ADDR],
2376			xprt->address_strings[RPC_DISPLAY_PORT]);
2377
2378	status = xs_tcp_finish_connecting(xprt, sock);
2379	trace_rpc_socket_connect(xprt, sock, status);
2380	dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2381			xprt, -status, xprt_connected(xprt),
2382			sock->sk->sk_state);
2383	switch (status) {
2384	default:
2385		printk("%s: connect returned unhandled error %d\n",
2386			__func__, status);
2387		/* fall through */
2388	case -EADDRNOTAVAIL:
2389		/* We're probably in TIME_WAIT. Get rid of existing socket,
2390		 * and retry
2391		 */
2392		xs_tcp_force_close(xprt);
2393		break;
2394	case 0:
2395	case -EINPROGRESS:
2396	case -EALREADY:
2397		xprt_unlock_connect(xprt, transport);
2398		return;
2399	case -EINVAL:
2400		/* Happens, for instance, if the user specified a link
2401		 * local IPv6 address without a scope-id.
2402		 */
2403	case -ECONNREFUSED:
2404	case -ECONNRESET:
2405	case -ENETDOWN:
2406	case -ENETUNREACH:
2407	case -EHOSTUNREACH:
2408	case -EADDRINUSE:
2409	case -ENOBUFS:
2410		/*
2411		 * xs_tcp_force_close() wakes tasks with -EIO.
2412		 * We need to wake them first to ensure the
2413		 * correct error code.
2414		 */
2415		xprt_wake_pending_tasks(xprt, status);
2416		xs_tcp_force_close(xprt);
2417		goto out;
2418	}
2419	status = -EAGAIN;
2420out:
2421	xprt_clear_connecting(xprt);
2422	xprt_unlock_connect(xprt, transport);
2423	xprt_wake_pending_tasks(xprt, status);
2424}
2425
2426/**
2427 * xs_connect - connect a socket to a remote endpoint
2428 * @xprt: pointer to transport structure
2429 * @task: address of RPC task that manages state of connect request
2430 *
2431 * TCP: If the remote end dropped the connection, delay reconnecting.
2432 *
2433 * UDP socket connects are synchronous, but we use a work queue anyway
2434 * to guarantee that even unprivileged user processes can set up a
2435 * socket on a privileged port.
2436 *
2437 * If a UDP socket connect fails, the delay behavior here prevents
2438 * retry floods (hard mounts).
2439 */
2440static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2441{
2442	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2443	unsigned long delay = 0;
2444
2445	WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2446
2447	if (transport->sock != NULL) {
2448		dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2449				"seconds\n",
2450				xprt, xprt->reestablish_timeout / HZ);
2451
2452		/* Start by resetting any existing state */
2453		xs_reset_transport(transport);
2454
2455		delay = xprt_reconnect_delay(xprt);
2456		xprt_reconnect_backoff(xprt, XS_TCP_INIT_REEST_TO);
2457
2458	} else
2459		dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2460
2461	queue_delayed_work(xprtiod_workqueue,
2462			&transport->connect_worker,
2463			delay);
2464}
2465
2466static void xs_wake_disconnect(struct sock_xprt *transport)
2467{
2468	if (test_and_clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state))
2469		xs_tcp_force_close(&transport->xprt);
2470}
2471
2472static void xs_wake_write(struct sock_xprt *transport)
2473{
2474	if (test_and_clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state))
2475		xprt_write_space(&transport->xprt);
2476}
2477
2478static void xs_wake_error(struct sock_xprt *transport)
2479{
2480	int sockerr;
2481
2482	if (!test_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2483		return;
2484	mutex_lock(&transport->recv_mutex);
2485	if (transport->sock == NULL)
2486		goto out;
2487	if (!test_and_clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2488		goto out;
2489	sockerr = xchg(&transport->xprt_err, 0);
2490	if (sockerr < 0)
2491		xprt_wake_pending_tasks(&transport->xprt, sockerr);
2492out:
2493	mutex_unlock(&transport->recv_mutex);
2494}
2495
2496static void xs_wake_pending(struct sock_xprt *transport)
2497{
2498	if (test_and_clear_bit(XPRT_SOCK_WAKE_PENDING, &transport->sock_state))
2499		xprt_wake_pending_tasks(&transport->xprt, -EAGAIN);
2500}
2501
2502static void xs_error_handle(struct work_struct *work)
2503{
2504	struct sock_xprt *transport = container_of(work,
2505			struct sock_xprt, error_worker);
2506
2507	xs_wake_disconnect(transport);
2508	xs_wake_write(transport);
2509	xs_wake_error(transport);
2510	xs_wake_pending(transport);
2511}
2512
2513/**
2514 * xs_local_print_stats - display AF_LOCAL socket-specifc stats
2515 * @xprt: rpc_xprt struct containing statistics
2516 * @seq: output file
2517 *
2518 */
2519static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2520{
2521	long idle_time = 0;
2522
2523	if (xprt_connected(xprt))
2524		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2525
2526	seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2527			"%llu %llu %lu %llu %llu\n",
2528			xprt->stat.bind_count,
2529			xprt->stat.connect_count,
2530			xprt->stat.connect_time / HZ,
2531			idle_time,
2532			xprt->stat.sends,
2533			xprt->stat.recvs,
2534			xprt->stat.bad_xids,
2535			xprt->stat.req_u,
2536			xprt->stat.bklog_u,
2537			xprt->stat.max_slots,
2538			xprt->stat.sending_u,
2539			xprt->stat.pending_u);
2540}
2541
2542/**
2543 * xs_udp_print_stats - display UDP socket-specifc stats
2544 * @xprt: rpc_xprt struct containing statistics
2545 * @seq: output file
2546 *
2547 */
2548static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2549{
2550	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2551
2552	seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2553			"%lu %llu %llu\n",
2554			transport->srcport,
2555			xprt->stat.bind_count,
2556			xprt->stat.sends,
2557			xprt->stat.recvs,
2558			xprt->stat.bad_xids,
2559			xprt->stat.req_u,
2560			xprt->stat.bklog_u,
2561			xprt->stat.max_slots,
2562			xprt->stat.sending_u,
2563			xprt->stat.pending_u);
2564}
2565
2566/**
2567 * xs_tcp_print_stats - display TCP socket-specifc stats
2568 * @xprt: rpc_xprt struct containing statistics
2569 * @seq: output file
2570 *
2571 */
2572static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2573{
2574	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2575	long idle_time = 0;
2576
2577	if (xprt_connected(xprt))
2578		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2579
2580	seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2581			"%llu %llu %lu %llu %llu\n",
2582			transport->srcport,
2583			xprt->stat.bind_count,
2584			xprt->stat.connect_count,
2585			xprt->stat.connect_time / HZ,
2586			idle_time,
2587			xprt->stat.sends,
2588			xprt->stat.recvs,
2589			xprt->stat.bad_xids,
2590			xprt->stat.req_u,
2591			xprt->stat.bklog_u,
2592			xprt->stat.max_slots,
2593			xprt->stat.sending_u,
2594			xprt->stat.pending_u);
2595}
2596
2597/*
2598 * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2599 * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2600 * to use the server side send routines.
2601 */
2602static int bc_malloc(struct rpc_task *task)
2603{
2604	struct rpc_rqst *rqst = task->tk_rqstp;
2605	size_t size = rqst->rq_callsize;
2606	struct page *page;
2607	struct rpc_buffer *buf;
2608
2609	if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2610		WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2611			  size);
2612		return -EINVAL;
2613	}
2614
2615	page = alloc_page(GFP_KERNEL);
2616	if (!page)
2617		return -ENOMEM;
2618
2619	buf = page_address(page);
2620	buf->len = PAGE_SIZE;
2621
2622	rqst->rq_buffer = buf->data;
2623	rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2624	return 0;
2625}
2626
2627/*
2628 * Free the space allocated in the bc_alloc routine
2629 */
2630static void bc_free(struct rpc_task *task)
2631{
2632	void *buffer = task->tk_rqstp->rq_buffer;
2633	struct rpc_buffer *buf;
2634
2635	buf = container_of(buffer, struct rpc_buffer, data);
2636	free_page((unsigned long)buf);
2637}
2638
2639/*
2640 * Use the svc_sock to send the callback. Must be called with svsk->sk_mutex
2641 * held. Borrows heavily from svc_tcp_sendto and xs_tcp_send_request.
2642 */
2643static int bc_sendto(struct rpc_rqst *req)
2644{
2645	int len;
2646	struct xdr_buf *xbufp = &req->rq_snd_buf;
2647	struct sock_xprt *transport =
2648			container_of(req->rq_xprt, struct sock_xprt, xprt);
2649	unsigned long headoff;
2650	unsigned long tailoff;
2651	struct page *tailpage;
2652	struct msghdr msg = {
2653		.msg_flags	= MSG_MORE
2654	};
2655	rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT |
2656					 (u32)xbufp->len);
2657	struct kvec iov = {
2658		.iov_base	= &marker,
2659		.iov_len	= sizeof(marker),
2660	};
2661
2662	len = kernel_sendmsg(transport->sock, &msg, &iov, 1, iov.iov_len);
2663	if (len != iov.iov_len)
2664		return -EAGAIN;
2665
2666	tailpage = NULL;
2667	if (xbufp->tail[0].iov_len)
2668		tailpage = virt_to_page(xbufp->tail[0].iov_base);
2669	tailoff = (unsigned long)xbufp->tail[0].iov_base & ~PAGE_MASK;
2670	headoff = (unsigned long)xbufp->head[0].iov_base & ~PAGE_MASK;
2671	len = svc_send_common(transport->sock, xbufp,
2672			      virt_to_page(xbufp->head[0].iov_base), headoff,
2673			      tailpage, tailoff);
2674	if (len != xbufp->len)
2675		return -EAGAIN;
2676	return len;
2677}
2678
2679/*
2680 * The send routine. Borrows from svc_send
 
 
 
 
 
 
 
 
2681 */
2682static int bc_send_request(struct rpc_rqst *req)
2683{
2684	struct svc_xprt	*xprt;
2685	int len;
2686
2687	dprintk("sending request with xid: %08x\n", ntohl(req->rq_xid));
2688	/*
2689	 * Get the server socket associated with this callback xprt
2690	 */
2691	xprt = req->rq_xprt->bc_xprt;
2692
2693	/*
2694	 * Grab the mutex to serialize data as the connection is shared
2695	 * with the fore channel
2696	 */
2697	mutex_lock(&xprt->xpt_mutex);
2698	if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2699		len = -ENOTCONN;
2700	else
2701		len = bc_sendto(req);
2702	mutex_unlock(&xprt->xpt_mutex);
2703
2704	if (len > 0)
2705		len = 0;
2706
2707	return len;
2708}
2709
2710/*
2711 * The close routine. Since this is client initiated, we do nothing
2712 */
2713
2714static void bc_close(struct rpc_xprt *xprt)
2715{
 
2716}
2717
2718/*
2719 * The xprt destroy routine. Again, because this connection is client
2720 * initiated, we do nothing
2721 */
2722
2723static void bc_destroy(struct rpc_xprt *xprt)
2724{
2725	dprintk("RPC:       bc_destroy xprt %p\n", xprt);
2726
2727	xs_xprt_free(xprt);
2728	module_put(THIS_MODULE);
2729}
2730
2731static const struct rpc_xprt_ops xs_local_ops = {
2732	.reserve_xprt		= xprt_reserve_xprt,
2733	.release_xprt		= xprt_release_xprt,
2734	.alloc_slot		= xprt_alloc_slot,
2735	.free_slot		= xprt_free_slot,
2736	.rpcbind		= xs_local_rpcbind,
2737	.set_port		= xs_local_set_port,
2738	.connect		= xs_local_connect,
2739	.buf_alloc		= rpc_malloc,
2740	.buf_free		= rpc_free,
2741	.prepare_request	= xs_stream_prepare_request,
2742	.send_request		= xs_local_send_request,
2743	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
2744	.close			= xs_close,
2745	.destroy		= xs_destroy,
2746	.print_stats		= xs_local_print_stats,
2747	.enable_swap		= xs_enable_swap,
2748	.disable_swap		= xs_disable_swap,
2749};
2750
2751static const struct rpc_xprt_ops xs_udp_ops = {
2752	.set_buffer_size	= xs_udp_set_buffer_size,
2753	.reserve_xprt		= xprt_reserve_xprt_cong,
2754	.release_xprt		= xprt_release_xprt_cong,
2755	.alloc_slot		= xprt_alloc_slot,
2756	.free_slot		= xprt_free_slot,
2757	.rpcbind		= rpcb_getport_async,
2758	.set_port		= xs_set_port,
2759	.connect		= xs_connect,
2760	.buf_alloc		= rpc_malloc,
2761	.buf_free		= rpc_free,
2762	.send_request		= xs_udp_send_request,
2763	.wait_for_reply_request	= xprt_wait_for_reply_request_rtt,
2764	.timer			= xs_udp_timer,
2765	.release_request	= xprt_release_rqst_cong,
2766	.close			= xs_close,
2767	.destroy		= xs_destroy,
2768	.print_stats		= xs_udp_print_stats,
2769	.enable_swap		= xs_enable_swap,
2770	.disable_swap		= xs_disable_swap,
2771	.inject_disconnect	= xs_inject_disconnect,
2772};
2773
2774static const struct rpc_xprt_ops xs_tcp_ops = {
2775	.reserve_xprt		= xprt_reserve_xprt,
2776	.release_xprt		= xprt_release_xprt,
2777	.alloc_slot		= xprt_alloc_slot,
2778	.free_slot		= xprt_free_slot,
2779	.rpcbind		= rpcb_getport_async,
2780	.set_port		= xs_set_port,
2781	.connect		= xs_connect,
2782	.buf_alloc		= rpc_malloc,
2783	.buf_free		= rpc_free,
2784	.prepare_request	= xs_stream_prepare_request,
2785	.send_request		= xs_tcp_send_request,
2786	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
2787	.close			= xs_tcp_shutdown,
2788	.destroy		= xs_destroy,
2789	.set_connect_timeout	= xs_tcp_set_connect_timeout,
2790	.print_stats		= xs_tcp_print_stats,
2791	.enable_swap		= xs_enable_swap,
2792	.disable_swap		= xs_disable_swap,
2793	.inject_disconnect	= xs_inject_disconnect,
2794#ifdef CONFIG_SUNRPC_BACKCHANNEL
2795	.bc_setup		= xprt_setup_bc,
2796	.bc_maxpayload		= xs_tcp_bc_maxpayload,
2797	.bc_num_slots		= xprt_bc_max_slots,
2798	.bc_free_rqst		= xprt_free_bc_rqst,
2799	.bc_destroy		= xprt_destroy_bc,
2800#endif
2801};
2802
2803/*
2804 * The rpc_xprt_ops for the server backchannel
2805 */
2806
2807static const struct rpc_xprt_ops bc_tcp_ops = {
2808	.reserve_xprt		= xprt_reserve_xprt,
2809	.release_xprt		= xprt_release_xprt,
2810	.alloc_slot		= xprt_alloc_slot,
2811	.free_slot		= xprt_free_slot,
2812	.buf_alloc		= bc_malloc,
2813	.buf_free		= bc_free,
2814	.send_request		= bc_send_request,
2815	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
2816	.close			= bc_close,
2817	.destroy		= bc_destroy,
2818	.print_stats		= xs_tcp_print_stats,
2819	.enable_swap		= xs_enable_swap,
2820	.disable_swap		= xs_disable_swap,
2821	.inject_disconnect	= xs_inject_disconnect,
2822};
2823
2824static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2825{
2826	static const struct sockaddr_in sin = {
2827		.sin_family		= AF_INET,
2828		.sin_addr.s_addr	= htonl(INADDR_ANY),
2829	};
2830	static const struct sockaddr_in6 sin6 = {
2831		.sin6_family		= AF_INET6,
2832		.sin6_addr		= IN6ADDR_ANY_INIT,
2833	};
2834
2835	switch (family) {
2836	case AF_LOCAL:
2837		break;
2838	case AF_INET:
2839		memcpy(sap, &sin, sizeof(sin));
2840		break;
2841	case AF_INET6:
2842		memcpy(sap, &sin6, sizeof(sin6));
2843		break;
2844	default:
2845		dprintk("RPC:       %s: Bad address family\n", __func__);
2846		return -EAFNOSUPPORT;
2847	}
2848	return 0;
2849}
2850
2851static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2852				      unsigned int slot_table_size,
2853				      unsigned int max_slot_table_size)
2854{
2855	struct rpc_xprt *xprt;
2856	struct sock_xprt *new;
2857
2858	if (args->addrlen > sizeof(xprt->addr)) {
2859		dprintk("RPC:       xs_setup_xprt: address too large\n");
2860		return ERR_PTR(-EBADF);
2861	}
2862
2863	xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2864			max_slot_table_size);
2865	if (xprt == NULL) {
2866		dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2867				"rpc_xprt\n");
2868		return ERR_PTR(-ENOMEM);
2869	}
2870
2871	new = container_of(xprt, struct sock_xprt, xprt);
2872	mutex_init(&new->recv_mutex);
2873	memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2874	xprt->addrlen = args->addrlen;
2875	if (args->srcaddr)
2876		memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2877	else {
2878		int err;
2879		err = xs_init_anyaddr(args->dstaddr->sa_family,
2880					(struct sockaddr *)&new->srcaddr);
2881		if (err != 0) {
2882			xprt_free(xprt);
2883			return ERR_PTR(err);
2884		}
2885	}
2886
2887	return xprt;
2888}
2889
2890static const struct rpc_timeout xs_local_default_timeout = {
2891	.to_initval = 10 * HZ,
2892	.to_maxval = 10 * HZ,
2893	.to_retries = 2,
2894};
2895
2896/**
2897 * xs_setup_local - Set up transport to use an AF_LOCAL socket
2898 * @args: rpc transport creation arguments
2899 *
2900 * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2901 */
2902static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2903{
2904	struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2905	struct sock_xprt *transport;
2906	struct rpc_xprt *xprt;
2907	struct rpc_xprt *ret;
2908
2909	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2910			xprt_max_tcp_slot_table_entries);
2911	if (IS_ERR(xprt))
2912		return xprt;
2913	transport = container_of(xprt, struct sock_xprt, xprt);
2914
2915	xprt->prot = 0;
2916	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2917
2918	xprt->bind_timeout = XS_BIND_TO;
2919	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2920	xprt->idle_timeout = XS_IDLE_DISC_TO;
2921
2922	xprt->ops = &xs_local_ops;
2923	xprt->timeout = &xs_local_default_timeout;
2924
2925	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2926	INIT_WORK(&transport->error_worker, xs_error_handle);
2927	INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket);
2928
2929	switch (sun->sun_family) {
2930	case AF_LOCAL:
2931		if (sun->sun_path[0] != '/') {
2932			dprintk("RPC:       bad AF_LOCAL address: %s\n",
2933					sun->sun_path);
2934			ret = ERR_PTR(-EINVAL);
2935			goto out_err;
2936		}
2937		xprt_set_bound(xprt);
2938		xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
2939		ret = ERR_PTR(xs_local_setup_socket(transport));
2940		if (ret)
2941			goto out_err;
2942		break;
2943	default:
2944		ret = ERR_PTR(-EAFNOSUPPORT);
2945		goto out_err;
2946	}
2947
2948	dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
2949			xprt->address_strings[RPC_DISPLAY_ADDR]);
2950
2951	if (try_module_get(THIS_MODULE))
2952		return xprt;
2953	ret = ERR_PTR(-EINVAL);
2954out_err:
2955	xs_xprt_free(xprt);
2956	return ret;
2957}
2958
2959static const struct rpc_timeout xs_udp_default_timeout = {
2960	.to_initval = 5 * HZ,
2961	.to_maxval = 30 * HZ,
2962	.to_increment = 5 * HZ,
2963	.to_retries = 5,
2964};
2965
2966/**
2967 * xs_setup_udp - Set up transport to use a UDP socket
2968 * @args: rpc transport creation arguments
2969 *
2970 */
2971static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2972{
2973	struct sockaddr *addr = args->dstaddr;
2974	struct rpc_xprt *xprt;
2975	struct sock_xprt *transport;
2976	struct rpc_xprt *ret;
2977
2978	xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2979			xprt_udp_slot_table_entries);
2980	if (IS_ERR(xprt))
2981		return xprt;
2982	transport = container_of(xprt, struct sock_xprt, xprt);
2983
2984	xprt->prot = IPPROTO_UDP;
2985	/* XXX: header size can vary due to auth type, IPv6, etc. */
2986	xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2987
2988	xprt->bind_timeout = XS_BIND_TO;
2989	xprt->reestablish_timeout = XS_UDP_REEST_TO;
2990	xprt->idle_timeout = XS_IDLE_DISC_TO;
2991
2992	xprt->ops = &xs_udp_ops;
2993
2994	xprt->timeout = &xs_udp_default_timeout;
2995
2996	INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
2997	INIT_WORK(&transport->error_worker, xs_error_handle);
2998	INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
2999
3000	switch (addr->sa_family) {
3001	case AF_INET:
3002		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3003			xprt_set_bound(xprt);
3004
3005		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
3006		break;
3007	case AF_INET6:
3008		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3009			xprt_set_bound(xprt);
3010
3011		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
3012		break;
3013	default:
3014		ret = ERR_PTR(-EAFNOSUPPORT);
3015		goto out_err;
3016	}
3017
3018	if (xprt_bound(xprt))
3019		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3020				xprt->address_strings[RPC_DISPLAY_ADDR],
3021				xprt->address_strings[RPC_DISPLAY_PORT],
3022				xprt->address_strings[RPC_DISPLAY_PROTO]);
3023	else
3024		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3025				xprt->address_strings[RPC_DISPLAY_ADDR],
3026				xprt->address_strings[RPC_DISPLAY_PROTO]);
3027
3028	if (try_module_get(THIS_MODULE))
3029		return xprt;
3030	ret = ERR_PTR(-EINVAL);
3031out_err:
3032	xs_xprt_free(xprt);
3033	return ret;
3034}
3035
3036static const struct rpc_timeout xs_tcp_default_timeout = {
3037	.to_initval = 60 * HZ,
3038	.to_maxval = 60 * HZ,
3039	.to_retries = 2,
3040};
3041
3042/**
3043 * xs_setup_tcp - Set up transport to use a TCP socket
3044 * @args: rpc transport creation arguments
3045 *
3046 */
3047static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
3048{
3049	struct sockaddr *addr = args->dstaddr;
3050	struct rpc_xprt *xprt;
3051	struct sock_xprt *transport;
3052	struct rpc_xprt *ret;
3053	unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
3054
3055	if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
3056		max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
3057
3058	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3059			max_slot_table_size);
3060	if (IS_ERR(xprt))
3061		return xprt;
3062	transport = container_of(xprt, struct sock_xprt, xprt);
3063
3064	xprt->prot = IPPROTO_TCP;
3065	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3066
3067	xprt->bind_timeout = XS_BIND_TO;
3068	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
3069	xprt->idle_timeout = XS_IDLE_DISC_TO;
3070
3071	xprt->ops = &xs_tcp_ops;
3072	xprt->timeout = &xs_tcp_default_timeout;
3073
3074	xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
3075	xprt->connect_timeout = xprt->timeout->to_initval *
3076		(xprt->timeout->to_retries + 1);
3077
3078	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
3079	INIT_WORK(&transport->error_worker, xs_error_handle);
3080	INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
3081
3082	switch (addr->sa_family) {
3083	case AF_INET:
3084		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3085			xprt_set_bound(xprt);
3086
3087		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
3088		break;
3089	case AF_INET6:
3090		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3091			xprt_set_bound(xprt);
3092
3093		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
3094		break;
3095	default:
3096		ret = ERR_PTR(-EAFNOSUPPORT);
3097		goto out_err;
3098	}
3099
3100	if (xprt_bound(xprt))
3101		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3102				xprt->address_strings[RPC_DISPLAY_ADDR],
3103				xprt->address_strings[RPC_DISPLAY_PORT],
3104				xprt->address_strings[RPC_DISPLAY_PROTO]);
3105	else
3106		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3107				xprt->address_strings[RPC_DISPLAY_ADDR],
3108				xprt->address_strings[RPC_DISPLAY_PROTO]);
3109
3110	if (try_module_get(THIS_MODULE))
3111		return xprt;
3112	ret = ERR_PTR(-EINVAL);
3113out_err:
3114	xs_xprt_free(xprt);
3115	return ret;
3116}
3117
3118/**
3119 * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
3120 * @args: rpc transport creation arguments
3121 *
3122 */
3123static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
3124{
3125	struct sockaddr *addr = args->dstaddr;
3126	struct rpc_xprt *xprt;
3127	struct sock_xprt *transport;
3128	struct svc_sock *bc_sock;
3129	struct rpc_xprt *ret;
3130
3131	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3132			xprt_tcp_slot_table_entries);
3133	if (IS_ERR(xprt))
3134		return xprt;
3135	transport = container_of(xprt, struct sock_xprt, xprt);
3136
3137	xprt->prot = IPPROTO_TCP;
3138	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3139	xprt->timeout = &xs_tcp_default_timeout;
3140
3141	/* backchannel */
3142	xprt_set_bound(xprt);
3143	xprt->bind_timeout = 0;
3144	xprt->reestablish_timeout = 0;
3145	xprt->idle_timeout = 0;
3146
3147	xprt->ops = &bc_tcp_ops;
3148
3149	switch (addr->sa_family) {
3150	case AF_INET:
3151		xs_format_peer_addresses(xprt, "tcp",
3152					 RPCBIND_NETID_TCP);
3153		break;
3154	case AF_INET6:
3155		xs_format_peer_addresses(xprt, "tcp",
3156				   RPCBIND_NETID_TCP6);
3157		break;
3158	default:
3159		ret = ERR_PTR(-EAFNOSUPPORT);
3160		goto out_err;
3161	}
3162
3163	dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3164			xprt->address_strings[RPC_DISPLAY_ADDR],
3165			xprt->address_strings[RPC_DISPLAY_PORT],
3166			xprt->address_strings[RPC_DISPLAY_PROTO]);
3167
3168	/*
3169	 * Once we've associated a backchannel xprt with a connection,
3170	 * we want to keep it around as long as the connection lasts,
3171	 * in case we need to start using it for a backchannel again;
3172	 * this reference won't be dropped until bc_xprt is destroyed.
3173	 */
3174	xprt_get(xprt);
3175	args->bc_xprt->xpt_bc_xprt = xprt;
3176	xprt->bc_xprt = args->bc_xprt;
3177	bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3178	transport->sock = bc_sock->sk_sock;
3179	transport->inet = bc_sock->sk_sk;
3180
3181	/*
3182	 * Since we don't want connections for the backchannel, we set
3183	 * the xprt status to connected
3184	 */
3185	xprt_set_connected(xprt);
3186
3187	if (try_module_get(THIS_MODULE))
3188		return xprt;
3189
3190	args->bc_xprt->xpt_bc_xprt = NULL;
3191	args->bc_xprt->xpt_bc_xps = NULL;
3192	xprt_put(xprt);
3193	ret = ERR_PTR(-EINVAL);
3194out_err:
3195	xs_xprt_free(xprt);
3196	return ret;
3197}
3198
3199static struct xprt_class	xs_local_transport = {
3200	.list		= LIST_HEAD_INIT(xs_local_transport.list),
3201	.name		= "named UNIX socket",
3202	.owner		= THIS_MODULE,
3203	.ident		= XPRT_TRANSPORT_LOCAL,
3204	.setup		= xs_setup_local,
3205};
3206
3207static struct xprt_class	xs_udp_transport = {
3208	.list		= LIST_HEAD_INIT(xs_udp_transport.list),
3209	.name		= "udp",
3210	.owner		= THIS_MODULE,
3211	.ident		= XPRT_TRANSPORT_UDP,
3212	.setup		= xs_setup_udp,
3213};
3214
3215static struct xprt_class	xs_tcp_transport = {
3216	.list		= LIST_HEAD_INIT(xs_tcp_transport.list),
3217	.name		= "tcp",
3218	.owner		= THIS_MODULE,
3219	.ident		= XPRT_TRANSPORT_TCP,
3220	.setup		= xs_setup_tcp,
3221};
3222
3223static struct xprt_class	xs_bc_tcp_transport = {
3224	.list		= LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3225	.name		= "tcp NFSv4.1 backchannel",
3226	.owner		= THIS_MODULE,
3227	.ident		= XPRT_TRANSPORT_BC_TCP,
3228	.setup		= xs_setup_bc_tcp,
3229};
3230
3231/**
3232 * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3233 *
3234 */
3235int init_socket_xprt(void)
3236{
3237	if (!sunrpc_table_header)
3238		sunrpc_table_header = register_sysctl_table(sunrpc_table);
3239
3240	xprt_register_transport(&xs_local_transport);
3241	xprt_register_transport(&xs_udp_transport);
3242	xprt_register_transport(&xs_tcp_transport);
3243	xprt_register_transport(&xs_bc_tcp_transport);
3244
3245	return 0;
3246}
3247
3248/**
3249 * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3250 *
3251 */
3252void cleanup_socket_xprt(void)
3253{
3254	if (sunrpc_table_header) {
3255		unregister_sysctl_table(sunrpc_table_header);
3256		sunrpc_table_header = NULL;
3257	}
3258
3259	xprt_unregister_transport(&xs_local_transport);
3260	xprt_unregister_transport(&xs_udp_transport);
3261	xprt_unregister_transport(&xs_tcp_transport);
3262	xprt_unregister_transport(&xs_bc_tcp_transport);
3263}
3264
3265static int param_set_uint_minmax(const char *val,
3266		const struct kernel_param *kp,
3267		unsigned int min, unsigned int max)
3268{
3269	unsigned int num;
3270	int ret;
3271
3272	if (!val)
3273		return -EINVAL;
3274	ret = kstrtouint(val, 0, &num);
3275	if (ret)
3276		return ret;
3277	if (num < min || num > max)
3278		return -EINVAL;
3279	*((unsigned int *)kp->arg) = num;
3280	return 0;
3281}
3282
3283static int param_set_portnr(const char *val, const struct kernel_param *kp)
3284{
3285	return param_set_uint_minmax(val, kp,
3286			RPC_MIN_RESVPORT,
3287			RPC_MAX_RESVPORT);
3288}
3289
3290static const struct kernel_param_ops param_ops_portnr = {
3291	.set = param_set_portnr,
3292	.get = param_get_uint,
3293};
3294
3295#define param_check_portnr(name, p) \
3296	__param_check(name, p, unsigned int);
3297
3298module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3299module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3300
3301static int param_set_slot_table_size(const char *val,
3302				     const struct kernel_param *kp)
3303{
3304	return param_set_uint_minmax(val, kp,
3305			RPC_MIN_SLOT_TABLE,
3306			RPC_MAX_SLOT_TABLE);
3307}
3308
3309static const struct kernel_param_ops param_ops_slot_table_size = {
3310	.set = param_set_slot_table_size,
3311	.get = param_get_uint,
3312};
3313
3314#define param_check_slot_table_size(name, p) \
3315	__param_check(name, p, unsigned int);
3316
3317static int param_set_max_slot_table_size(const char *val,
3318				     const struct kernel_param *kp)
3319{
3320	return param_set_uint_minmax(val, kp,
3321			RPC_MIN_SLOT_TABLE,
3322			RPC_MAX_SLOT_TABLE_LIMIT);
3323}
3324
3325static const struct kernel_param_ops param_ops_max_slot_table_size = {
3326	.set = param_set_max_slot_table_size,
3327	.get = param_get_uint,
3328};
3329
3330#define param_check_max_slot_table_size(name, p) \
3331	__param_check(name, p, unsigned int);
3332
3333module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3334		   slot_table_size, 0644);
3335module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3336		   max_slot_table_size, 0644);
3337module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3338		   slot_table_size, 0644);