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v6.2
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * linux/net/sunrpc/xprtsock.c
   4 *
   5 * Client-side transport implementation for sockets.
   6 *
   7 * TCP callback races fixes (C) 1998 Red Hat
   8 * TCP send fixes (C) 1998 Red Hat
   9 * TCP NFS related read + write fixes
  10 *  (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
  11 *
  12 * Rewrite of larges part of the code in order to stabilize TCP stuff.
  13 * Fix behaviour when socket buffer is full.
  14 *  (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no>
  15 *
  16 * IP socket transport implementation, (C) 2005 Chuck Lever <cel@netapp.com>
  17 *
  18 * IPv6 support contributed by Gilles Quillard, Bull Open Source, 2005.
  19 *   <gilles.quillard@bull.net>
  20 */
  21
  22#include <linux/types.h>
  23#include <linux/string.h>
  24#include <linux/slab.h>
  25#include <linux/module.h>
  26#include <linux/capability.h>
  27#include <linux/pagemap.h>
  28#include <linux/errno.h>
  29#include <linux/socket.h>
  30#include <linux/in.h>
  31#include <linux/net.h>
  32#include <linux/mm.h>
  33#include <linux/un.h>
  34#include <linux/udp.h>
  35#include <linux/tcp.h>
  36#include <linux/sunrpc/clnt.h>
  37#include <linux/sunrpc/addr.h>
  38#include <linux/sunrpc/sched.h>
  39#include <linux/sunrpc/svcsock.h>
  40#include <linux/sunrpc/xprtsock.h>
  41#include <linux/file.h>
  42#ifdef CONFIG_SUNRPC_BACKCHANNEL
  43#include <linux/sunrpc/bc_xprt.h>
  44#endif
  45
  46#include <net/sock.h>
  47#include <net/checksum.h>
  48#include <net/udp.h>
  49#include <net/tcp.h>
  50#include <linux/bvec.h>
  51#include <linux/highmem.h>
  52#include <linux/uio.h>
  53#include <linux/sched/mm.h>
  54
  55#include <trace/events/sunrpc.h>
  56
  57#include "socklib.h"
  58#include "sunrpc.h"
  59
  60static void xs_close(struct rpc_xprt *xprt);
  61static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock);
  62static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
  63		struct socket *sock);
  64
  65/*
  66 * xprtsock tunables
  67 */
  68static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  69static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
  70static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
  71
  72static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
  73static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
  74
  75#define XS_TCP_LINGER_TO	(15U * HZ)
  76static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
  77
  78/*
  79 * We can register our own files under /proc/sys/sunrpc by
  80 * calling register_sysctl_table() again.  The files in that
  81 * directory become the union of all files registered there.
  82 *
  83 * We simply need to make sure that we don't collide with
  84 * someone else's file names!
  85 */
  86
  87static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
  88static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
  89static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
  90static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
  91static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
  92
  93static struct ctl_table_header *sunrpc_table_header;
  94
  95static struct xprt_class xs_local_transport;
  96static struct xprt_class xs_udp_transport;
  97static struct xprt_class xs_tcp_transport;
  98static struct xprt_class xs_bc_tcp_transport;
  99
 100/*
 101 * FIXME: changing the UDP slot table size should also resize the UDP
 102 *        socket buffers for existing UDP transports
 103 */
 104static struct ctl_table xs_tunables_table[] = {
 105	{
 106		.procname	= "udp_slot_table_entries",
 107		.data		= &xprt_udp_slot_table_entries,
 108		.maxlen		= sizeof(unsigned int),
 109		.mode		= 0644,
 110		.proc_handler	= proc_dointvec_minmax,
 111		.extra1		= &min_slot_table_size,
 112		.extra2		= &max_slot_table_size
 113	},
 114	{
 115		.procname	= "tcp_slot_table_entries",
 116		.data		= &xprt_tcp_slot_table_entries,
 117		.maxlen		= sizeof(unsigned int),
 118		.mode		= 0644,
 119		.proc_handler	= proc_dointvec_minmax,
 120		.extra1		= &min_slot_table_size,
 121		.extra2		= &max_slot_table_size
 122	},
 123	{
 124		.procname	= "tcp_max_slot_table_entries",
 125		.data		= &xprt_max_tcp_slot_table_entries,
 126		.maxlen		= sizeof(unsigned int),
 127		.mode		= 0644,
 128		.proc_handler	= proc_dointvec_minmax,
 129		.extra1		= &min_slot_table_size,
 130		.extra2		= &max_tcp_slot_table_limit
 131	},
 132	{
 133		.procname	= "min_resvport",
 134		.data		= &xprt_min_resvport,
 135		.maxlen		= sizeof(unsigned int),
 136		.mode		= 0644,
 137		.proc_handler	= proc_dointvec_minmax,
 138		.extra1		= &xprt_min_resvport_limit,
 139		.extra2		= &xprt_max_resvport_limit
 140	},
 141	{
 142		.procname	= "max_resvport",
 143		.data		= &xprt_max_resvport,
 144		.maxlen		= sizeof(unsigned int),
 145		.mode		= 0644,
 146		.proc_handler	= proc_dointvec_minmax,
 147		.extra1		= &xprt_min_resvport_limit,
 148		.extra2		= &xprt_max_resvport_limit
 149	},
 150	{
 151		.procname	= "tcp_fin_timeout",
 152		.data		= &xs_tcp_fin_timeout,
 153		.maxlen		= sizeof(xs_tcp_fin_timeout),
 154		.mode		= 0644,
 155		.proc_handler	= proc_dointvec_jiffies,
 156	},
 157	{ },
 158};
 159
 160static struct ctl_table sunrpc_table[] = {
 161	{
 162		.procname	= "sunrpc",
 163		.mode		= 0555,
 164		.child		= xs_tunables_table
 165	},
 166	{ },
 167};
 168
 169/*
 170 * Wait duration for a reply from the RPC portmapper.
 171 */
 172#define XS_BIND_TO		(60U * HZ)
 173
 174/*
 175 * Delay if a UDP socket connect error occurs.  This is most likely some
 176 * kind of resource problem on the local host.
 177 */
 178#define XS_UDP_REEST_TO		(2U * HZ)
 179
 180/*
 181 * The reestablish timeout allows clients to delay for a bit before attempting
 182 * to reconnect to a server that just dropped our connection.
 183 *
 184 * We implement an exponential backoff when trying to reestablish a TCP
 185 * transport connection with the server.  Some servers like to drop a TCP
 186 * connection when they are overworked, so we start with a short timeout and
 187 * increase over time if the server is down or not responding.
 188 */
 189#define XS_TCP_INIT_REEST_TO	(3U * HZ)
 190
 191/*
 192 * TCP idle timeout; client drops the transport socket if it is idle
 193 * for this long.  Note that we also timeout UDP sockets to prevent
 194 * holding port numbers when there is no RPC traffic.
 195 */
 196#define XS_IDLE_DISC_TO		(5U * 60 * HZ)
 197
 198#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 199# undef  RPC_DEBUG_DATA
 200# define RPCDBG_FACILITY	RPCDBG_TRANS
 201#endif
 202
 203#ifdef RPC_DEBUG_DATA
 204static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 205{
 206	u8 *buf = (u8 *) packet;
 207	int j;
 208
 209	dprintk("RPC:       %s\n", msg);
 210	for (j = 0; j < count && j < 128; j += 4) {
 211		if (!(j & 31)) {
 212			if (j)
 213				dprintk("\n");
 214			dprintk("0x%04x ", j);
 215		}
 216		dprintk("%02x%02x%02x%02x ",
 217			buf[j], buf[j+1], buf[j+2], buf[j+3]);
 218	}
 219	dprintk("\n");
 220}
 221#else
 222static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 223{
 224	/* NOP */
 225}
 226#endif
 227
 228static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
 229{
 230	return (struct rpc_xprt *) sk->sk_user_data;
 231}
 232
 233static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
 234{
 235	return (struct sockaddr *) &xprt->addr;
 236}
 237
 238static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
 239{
 240	return (struct sockaddr_un *) &xprt->addr;
 241}
 242
 243static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
 244{
 245	return (struct sockaddr_in *) &xprt->addr;
 246}
 247
 248static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
 249{
 250	return (struct sockaddr_in6 *) &xprt->addr;
 251}
 252
 253static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
 254{
 255	struct sockaddr *sap = xs_addr(xprt);
 256	struct sockaddr_in6 *sin6;
 257	struct sockaddr_in *sin;
 258	struct sockaddr_un *sun;
 259	char buf[128];
 260
 261	switch (sap->sa_family) {
 262	case AF_LOCAL:
 263		sun = xs_addr_un(xprt);
 264		strscpy(buf, sun->sun_path, sizeof(buf));
 265		xprt->address_strings[RPC_DISPLAY_ADDR] =
 266						kstrdup(buf, GFP_KERNEL);
 267		break;
 268	case AF_INET:
 269		(void)rpc_ntop(sap, buf, sizeof(buf));
 270		xprt->address_strings[RPC_DISPLAY_ADDR] =
 271						kstrdup(buf, GFP_KERNEL);
 272		sin = xs_addr_in(xprt);
 273		snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
 274		break;
 275	case AF_INET6:
 276		(void)rpc_ntop(sap, buf, sizeof(buf));
 277		xprt->address_strings[RPC_DISPLAY_ADDR] =
 278						kstrdup(buf, GFP_KERNEL);
 279		sin6 = xs_addr_in6(xprt);
 280		snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
 281		break;
 282	default:
 283		BUG();
 284	}
 285
 286	xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
 287}
 288
 289static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
 290{
 291	struct sockaddr *sap = xs_addr(xprt);
 292	char buf[128];
 293
 294	snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
 295	xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
 296
 297	snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
 298	xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
 299}
 300
 301static void xs_format_peer_addresses(struct rpc_xprt *xprt,
 302				     const char *protocol,
 303				     const char *netid)
 304{
 305	xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
 306	xprt->address_strings[RPC_DISPLAY_NETID] = netid;
 307	xs_format_common_peer_addresses(xprt);
 308	xs_format_common_peer_ports(xprt);
 309}
 310
 311static void xs_update_peer_port(struct rpc_xprt *xprt)
 312{
 313	kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
 314	kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
 315
 316	xs_format_common_peer_ports(xprt);
 317}
 318
 319static void xs_free_peer_addresses(struct rpc_xprt *xprt)
 320{
 321	unsigned int i;
 322
 323	for (i = 0; i < RPC_DISPLAY_MAX; i++)
 324		switch (i) {
 325		case RPC_DISPLAY_PROTO:
 326		case RPC_DISPLAY_NETID:
 327			continue;
 328		default:
 329			kfree(xprt->address_strings[i]);
 330		}
 331}
 332
 333static size_t
 334xs_alloc_sparse_pages(struct xdr_buf *buf, size_t want, gfp_t gfp)
 335{
 336	size_t i,n;
 337
 338	if (!want || !(buf->flags & XDRBUF_SPARSE_PAGES))
 339		return want;
 340	n = (buf->page_base + want + PAGE_SIZE - 1) >> PAGE_SHIFT;
 341	for (i = 0; i < n; i++) {
 342		if (buf->pages[i])
 343			continue;
 344		buf->bvec[i].bv_page = buf->pages[i] = alloc_page(gfp);
 345		if (!buf->pages[i]) {
 346			i *= PAGE_SIZE;
 347			return i > buf->page_base ? i - buf->page_base : 0;
 348		}
 349	}
 350	return want;
 351}
 352
 353static ssize_t
 354xs_sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags, size_t seek)
 355{
 356	ssize_t ret;
 357	if (seek != 0)
 358		iov_iter_advance(&msg->msg_iter, seek);
 359	ret = sock_recvmsg(sock, msg, flags);
 360	return ret > 0 ? ret + seek : ret;
 361}
 362
 363static ssize_t
 364xs_read_kvec(struct socket *sock, struct msghdr *msg, int flags,
 365		struct kvec *kvec, size_t count, size_t seek)
 366{
 367	iov_iter_kvec(&msg->msg_iter, ITER_DEST, kvec, 1, count);
 368	return xs_sock_recvmsg(sock, msg, flags, seek);
 369}
 370
 371static ssize_t
 372xs_read_bvec(struct socket *sock, struct msghdr *msg, int flags,
 373		struct bio_vec *bvec, unsigned long nr, size_t count,
 374		size_t seek)
 375{
 376	iov_iter_bvec(&msg->msg_iter, ITER_DEST, bvec, nr, count);
 377	return xs_sock_recvmsg(sock, msg, flags, seek);
 378}
 379
 380static ssize_t
 381xs_read_discard(struct socket *sock, struct msghdr *msg, int flags,
 382		size_t count)
 383{
 384	iov_iter_discard(&msg->msg_iter, ITER_DEST, count);
 385	return sock_recvmsg(sock, msg, flags);
 386}
 387
 388#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
 389static void
 390xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
 391{
 392	struct bvec_iter bi = {
 393		.bi_size = count,
 394	};
 395	struct bio_vec bv;
 396
 397	bvec_iter_advance(bvec, &bi, seek & PAGE_MASK);
 398	for_each_bvec(bv, bvec, bi, bi)
 399		flush_dcache_page(bv.bv_page);
 400}
 401#else
 402static inline void
 403xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
 404{
 405}
 406#endif
 407
 408static ssize_t
 409xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags,
 410		struct xdr_buf *buf, size_t count, size_t seek, size_t *read)
 411{
 412	size_t want, seek_init = seek, offset = 0;
 413	ssize_t ret;
 414
 415	want = min_t(size_t, count, buf->head[0].iov_len);
 416	if (seek < want) {
 417		ret = xs_read_kvec(sock, msg, flags, &buf->head[0], want, seek);
 418		if (ret <= 0)
 419			goto sock_err;
 420		offset += ret;
 421		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 422			goto out;
 423		if (ret != want)
 424			goto out;
 425		seek = 0;
 426	} else {
 427		seek -= want;
 428		offset += want;
 429	}
 430
 431	want = xs_alloc_sparse_pages(
 432		buf, min_t(size_t, count - offset, buf->page_len),
 433		GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
 434	if (seek < want) {
 435		ret = xs_read_bvec(sock, msg, flags, buf->bvec,
 436				xdr_buf_pagecount(buf),
 437				want + buf->page_base,
 438				seek + buf->page_base);
 439		if (ret <= 0)
 440			goto sock_err;
 441		xs_flush_bvec(buf->bvec, ret, seek + buf->page_base);
 442		ret -= buf->page_base;
 443		offset += ret;
 444		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 445			goto out;
 446		if (ret != want)
 447			goto out;
 448		seek = 0;
 449	} else {
 450		seek -= want;
 451		offset += want;
 452	}
 453
 454	want = min_t(size_t, count - offset, buf->tail[0].iov_len);
 455	if (seek < want) {
 456		ret = xs_read_kvec(sock, msg, flags, &buf->tail[0], want, seek);
 457		if (ret <= 0)
 458			goto sock_err;
 459		offset += ret;
 460		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 461			goto out;
 462		if (ret != want)
 463			goto out;
 464	} else if (offset < seek_init)
 465		offset = seek_init;
 466	ret = -EMSGSIZE;
 467out:
 468	*read = offset - seek_init;
 469	return ret;
 470sock_err:
 471	offset += seek;
 472	goto out;
 473}
 474
 475static void
 476xs_read_header(struct sock_xprt *transport, struct xdr_buf *buf)
 477{
 478	if (!transport->recv.copied) {
 479		if (buf->head[0].iov_len >= transport->recv.offset)
 480			memcpy(buf->head[0].iov_base,
 481					&transport->recv.xid,
 482					transport->recv.offset);
 483		transport->recv.copied = transport->recv.offset;
 484	}
 485}
 486
 487static bool
 488xs_read_stream_request_done(struct sock_xprt *transport)
 489{
 490	return transport->recv.fraghdr & cpu_to_be32(RPC_LAST_STREAM_FRAGMENT);
 491}
 492
 493static void
 494xs_read_stream_check_eor(struct sock_xprt *transport,
 495		struct msghdr *msg)
 496{
 497	if (xs_read_stream_request_done(transport))
 498		msg->msg_flags |= MSG_EOR;
 499}
 500
 501static ssize_t
 502xs_read_stream_request(struct sock_xprt *transport, struct msghdr *msg,
 503		int flags, struct rpc_rqst *req)
 504{
 505	struct xdr_buf *buf = &req->rq_private_buf;
 506	size_t want, read;
 507	ssize_t ret;
 508
 509	xs_read_header(transport, buf);
 510
 511	want = transport->recv.len - transport->recv.offset;
 512	if (want != 0) {
 513		ret = xs_read_xdr_buf(transport->sock, msg, flags, buf,
 514				transport->recv.copied + want,
 515				transport->recv.copied,
 516				&read);
 517		transport->recv.offset += read;
 518		transport->recv.copied += read;
 519	}
 520
 521	if (transport->recv.offset == transport->recv.len)
 522		xs_read_stream_check_eor(transport, msg);
 523
 524	if (want == 0)
 525		return 0;
 526
 527	switch (ret) {
 528	default:
 529		break;
 530	case -EFAULT:
 531	case -EMSGSIZE:
 532		msg->msg_flags |= MSG_TRUNC;
 533		return read;
 534	case 0:
 535		return -ESHUTDOWN;
 536	}
 537	return ret < 0 ? ret : read;
 538}
 539
 540static size_t
 541xs_read_stream_headersize(bool isfrag)
 542{
 543	if (isfrag)
 544		return sizeof(__be32);
 545	return 3 * sizeof(__be32);
 546}
 547
 548static ssize_t
 549xs_read_stream_header(struct sock_xprt *transport, struct msghdr *msg,
 550		int flags, size_t want, size_t seek)
 551{
 552	struct kvec kvec = {
 553		.iov_base = &transport->recv.fraghdr,
 554		.iov_len = want,
 555	};
 556	return xs_read_kvec(transport->sock, msg, flags, &kvec, want, seek);
 557}
 558
 559#if defined(CONFIG_SUNRPC_BACKCHANNEL)
 560static ssize_t
 561xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 562{
 563	struct rpc_xprt *xprt = &transport->xprt;
 564	struct rpc_rqst *req;
 565	ssize_t ret;
 566
 567	/* Is this transport associated with the backchannel? */
 568	if (!xprt->bc_serv)
 569		return -ESHUTDOWN;
 570
 571	/* Look up and lock the request corresponding to the given XID */
 572	req = xprt_lookup_bc_request(xprt, transport->recv.xid);
 573	if (!req) {
 574		printk(KERN_WARNING "Callback slot table overflowed\n");
 575		return -ESHUTDOWN;
 576	}
 577	if (transport->recv.copied && !req->rq_private_buf.len)
 578		return -ESHUTDOWN;
 579
 580	ret = xs_read_stream_request(transport, msg, flags, req);
 581	if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 582		xprt_complete_bc_request(req, transport->recv.copied);
 583	else
 584		req->rq_private_buf.len = transport->recv.copied;
 585
 586	return ret;
 587}
 588#else /* CONFIG_SUNRPC_BACKCHANNEL */
 589static ssize_t
 590xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 591{
 592	return -ESHUTDOWN;
 593}
 594#endif /* CONFIG_SUNRPC_BACKCHANNEL */
 595
 596static ssize_t
 597xs_read_stream_reply(struct sock_xprt *transport, struct msghdr *msg, int flags)
 598{
 599	struct rpc_xprt *xprt = &transport->xprt;
 600	struct rpc_rqst *req;
 601	ssize_t ret = 0;
 602
 603	/* Look up and lock the request corresponding to the given XID */
 604	spin_lock(&xprt->queue_lock);
 605	req = xprt_lookup_rqst(xprt, transport->recv.xid);
 606	if (!req || (transport->recv.copied && !req->rq_private_buf.len)) {
 607		msg->msg_flags |= MSG_TRUNC;
 608		goto out;
 609	}
 610	xprt_pin_rqst(req);
 611	spin_unlock(&xprt->queue_lock);
 612
 613	ret = xs_read_stream_request(transport, msg, flags, req);
 614
 615	spin_lock(&xprt->queue_lock);
 616	if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 617		xprt_complete_rqst(req->rq_task, transport->recv.copied);
 618	else
 619		req->rq_private_buf.len = transport->recv.copied;
 620	xprt_unpin_rqst(req);
 621out:
 622	spin_unlock(&xprt->queue_lock);
 623	return ret;
 624}
 625
 626static ssize_t
 627xs_read_stream(struct sock_xprt *transport, int flags)
 628{
 629	struct msghdr msg = { 0 };
 630	size_t want, read = 0;
 631	ssize_t ret = 0;
 632
 633	if (transport->recv.len == 0) {
 634		want = xs_read_stream_headersize(transport->recv.copied != 0);
 635		ret = xs_read_stream_header(transport, &msg, flags, want,
 636				transport->recv.offset);
 637		if (ret <= 0)
 638			goto out_err;
 639		transport->recv.offset = ret;
 640		if (transport->recv.offset != want)
 641			return transport->recv.offset;
 642		transport->recv.len = be32_to_cpu(transport->recv.fraghdr) &
 643			RPC_FRAGMENT_SIZE_MASK;
 644		transport->recv.offset -= sizeof(transport->recv.fraghdr);
 645		read = ret;
 646	}
 647
 648	switch (be32_to_cpu(transport->recv.calldir)) {
 649	default:
 650		msg.msg_flags |= MSG_TRUNC;
 651		break;
 652	case RPC_CALL:
 653		ret = xs_read_stream_call(transport, &msg, flags);
 654		break;
 655	case RPC_REPLY:
 656		ret = xs_read_stream_reply(transport, &msg, flags);
 657	}
 658	if (msg.msg_flags & MSG_TRUNC) {
 659		transport->recv.calldir = cpu_to_be32(-1);
 660		transport->recv.copied = -1;
 661	}
 662	if (ret < 0)
 663		goto out_err;
 664	read += ret;
 665	if (transport->recv.offset < transport->recv.len) {
 666		if (!(msg.msg_flags & MSG_TRUNC))
 667			return read;
 668		msg.msg_flags = 0;
 669		ret = xs_read_discard(transport->sock, &msg, flags,
 670				transport->recv.len - transport->recv.offset);
 671		if (ret <= 0)
 672			goto out_err;
 673		transport->recv.offset += ret;
 674		read += ret;
 675		if (transport->recv.offset != transport->recv.len)
 676			return read;
 677	}
 678	if (xs_read_stream_request_done(transport)) {
 679		trace_xs_stream_read_request(transport);
 680		transport->recv.copied = 0;
 681	}
 682	transport->recv.offset = 0;
 683	transport->recv.len = 0;
 684	return read;
 685out_err:
 686	return ret != 0 ? ret : -ESHUTDOWN;
 687}
 688
 689static __poll_t xs_poll_socket(struct sock_xprt *transport)
 690{
 691	return transport->sock->ops->poll(transport->file, transport->sock,
 692			NULL);
 693}
 694
 695static bool xs_poll_socket_readable(struct sock_xprt *transport)
 696{
 697	__poll_t events = xs_poll_socket(transport);
 698
 699	return (events & (EPOLLIN | EPOLLRDNORM)) && !(events & EPOLLRDHUP);
 700}
 701
 702static void xs_poll_check_readable(struct sock_xprt *transport)
 703{
 704
 705	clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
 706	if (!xs_poll_socket_readable(transport))
 707		return;
 708	if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
 709		queue_work(xprtiod_workqueue, &transport->recv_worker);
 710}
 711
 712static void xs_stream_data_receive(struct sock_xprt *transport)
 713{
 714	size_t read = 0;
 715	ssize_t ret = 0;
 716
 717	mutex_lock(&transport->recv_mutex);
 718	if (transport->sock == NULL)
 719		goto out;
 720	for (;;) {
 721		ret = xs_read_stream(transport, MSG_DONTWAIT);
 722		if (ret < 0)
 723			break;
 724		read += ret;
 725		cond_resched();
 726	}
 727	if (ret == -ESHUTDOWN)
 728		kernel_sock_shutdown(transport->sock, SHUT_RDWR);
 729	else
 730		xs_poll_check_readable(transport);
 731out:
 732	mutex_unlock(&transport->recv_mutex);
 733	trace_xs_stream_read_data(&transport->xprt, ret, read);
 734}
 735
 736static void xs_stream_data_receive_workfn(struct work_struct *work)
 737{
 738	struct sock_xprt *transport =
 739		container_of(work, struct sock_xprt, recv_worker);
 740	unsigned int pflags = memalloc_nofs_save();
 741
 742	xs_stream_data_receive(transport);
 743	memalloc_nofs_restore(pflags);
 744}
 745
 746static void
 747xs_stream_reset_connect(struct sock_xprt *transport)
 748{
 749	transport->recv.offset = 0;
 750	transport->recv.len = 0;
 751	transport->recv.copied = 0;
 752	transport->xmit.offset = 0;
 753}
 754
 755static void
 756xs_stream_start_connect(struct sock_xprt *transport)
 757{
 758	transport->xprt.stat.connect_count++;
 759	transport->xprt.stat.connect_start = jiffies;
 760}
 761
 762#define XS_SENDMSG_FLAGS	(MSG_DONTWAIT | MSG_NOSIGNAL)
 763
 764/**
 765 * xs_nospace - handle transmit was incomplete
 766 * @req: pointer to RPC request
 767 * @transport: pointer to struct sock_xprt
 768 *
 769 */
 770static int xs_nospace(struct rpc_rqst *req, struct sock_xprt *transport)
 771{
 772	struct rpc_xprt *xprt = &transport->xprt;
 
 773	struct sock *sk = transport->inet;
 774	int ret = -EAGAIN;
 775
 776	trace_rpc_socket_nospace(req, transport);
 777
 778	/* Protect against races with write_space */
 779	spin_lock(&xprt->transport_lock);
 780
 781	/* Don't race with disconnect */
 782	if (xprt_connected(xprt)) {
 783		/* wait for more buffer space */
 784		set_bit(XPRT_SOCK_NOSPACE, &transport->sock_state);
 785		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
 786		sk->sk_write_pending++;
 787		xprt_wait_for_buffer_space(xprt);
 788	} else
 789		ret = -ENOTCONN;
 790
 791	spin_unlock(&xprt->transport_lock);
 792	return ret;
 793}
 794
 795static int xs_sock_nospace(struct rpc_rqst *req)
 796{
 797	struct sock_xprt *transport =
 798		container_of(req->rq_xprt, struct sock_xprt, xprt);
 799	struct sock *sk = transport->inet;
 800	int ret = -EAGAIN;
 
 
 801
 802	lock_sock(sk);
 803	if (!sock_writeable(sk))
 804		ret = xs_nospace(req, transport);
 805	release_sock(sk);
 806	return ret;
 807}
 808
 809static int xs_stream_nospace(struct rpc_rqst *req, bool vm_wait)
 810{
 811	struct sock_xprt *transport =
 812		container_of(req->rq_xprt, struct sock_xprt, xprt);
 813	struct sock *sk = transport->inet;
 814	int ret = -EAGAIN;
 815
 816	if (vm_wait)
 817		return -ENOBUFS;
 818	lock_sock(sk);
 819	if (!sk_stream_memory_free(sk))
 820		ret = xs_nospace(req, transport);
 821	release_sock(sk);
 822	return ret;
 823}
 824
 825static int xs_stream_prepare_request(struct rpc_rqst *req, struct xdr_buf *buf)
 
 826{
 827	return xdr_alloc_bvec(buf, rpc_task_gfp_mask());
 
 828}
 829
 830/*
 831 * Determine if the previous message in the stream was aborted before it
 832 * could complete transmission.
 833 */
 834static bool
 835xs_send_request_was_aborted(struct sock_xprt *transport, struct rpc_rqst *req)
 836{
 837	return transport->xmit.offset != 0 && req->rq_bytes_sent == 0;
 838}
 839
 840/*
 841 * Return the stream record marker field for a record of length < 2^31-1
 842 */
 843static rpc_fraghdr
 844xs_stream_record_marker(struct xdr_buf *xdr)
 845{
 846	if (!xdr->len)
 847		return 0;
 848	return cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | (u32)xdr->len);
 849}
 850
 851/**
 852 * xs_local_send_request - write an RPC request to an AF_LOCAL socket
 853 * @req: pointer to RPC request
 854 *
 855 * Return values:
 856 *        0:	The request has been sent
 857 *   EAGAIN:	The socket was blocked, please call again later to
 858 *		complete the request
 859 * ENOTCONN:	Caller needs to invoke connect logic then call again
 860 *    other:	Some other error occurred, the request was not sent
 861 */
 862static int xs_local_send_request(struct rpc_rqst *req)
 863{
 864	struct rpc_xprt *xprt = req->rq_xprt;
 865	struct sock_xprt *transport =
 866				container_of(xprt, struct sock_xprt, xprt);
 867	struct xdr_buf *xdr = &req->rq_snd_buf;
 868	rpc_fraghdr rm = xs_stream_record_marker(xdr);
 869	unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
 870	struct msghdr msg = {
 871		.msg_flags	= XS_SENDMSG_FLAGS,
 872	};
 873	bool vm_wait;
 874	unsigned int sent;
 875	int status;
 876
 877	/* Close the stream if the previous transmission was incomplete */
 878	if (xs_send_request_was_aborted(transport, req)) {
 879		xprt_force_disconnect(xprt);
 880		return -ENOTCONN;
 881	}
 882
 883	xs_pktdump("packet data:",
 884			req->rq_svec->iov_base, req->rq_svec->iov_len);
 885
 886	vm_wait = sk_stream_is_writeable(transport->inet) ? true : false;
 887
 888	req->rq_xtime = ktime_get();
 889	status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
 890				   transport->xmit.offset, rm, &sent);
 891	dprintk("RPC:       %s(%u) = %d\n",
 892			__func__, xdr->len - transport->xmit.offset, status);
 893
 
 
 
 894	if (likely(sent > 0) || status == 0) {
 895		transport->xmit.offset += sent;
 896		req->rq_bytes_sent = transport->xmit.offset;
 897		if (likely(req->rq_bytes_sent >= msglen)) {
 898			req->rq_xmit_bytes_sent += transport->xmit.offset;
 899			transport->xmit.offset = 0;
 900			return 0;
 901		}
 902		status = -EAGAIN;
 903		vm_wait = false;
 904	}
 905
 906	switch (status) {
 
 
 907	case -EAGAIN:
 908		status = xs_stream_nospace(req, vm_wait);
 909		break;
 910	default:
 911		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 912			-status);
 913		fallthrough;
 914	case -EPIPE:
 915		xprt_force_disconnect(xprt);
 916		status = -ENOTCONN;
 917	}
 918
 919	return status;
 920}
 921
 922/**
 923 * xs_udp_send_request - write an RPC request to a UDP socket
 924 * @req: pointer to RPC request
 925 *
 926 * Return values:
 927 *        0:	The request has been sent
 928 *   EAGAIN:	The socket was blocked, please call again later to
 929 *		complete the request
 930 * ENOTCONN:	Caller needs to invoke connect logic then call again
 931 *    other:	Some other error occurred, the request was not sent
 932 */
 933static int xs_udp_send_request(struct rpc_rqst *req)
 934{
 935	struct rpc_xprt *xprt = req->rq_xprt;
 936	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 937	struct xdr_buf *xdr = &req->rq_snd_buf;
 938	struct msghdr msg = {
 939		.msg_name	= xs_addr(xprt),
 940		.msg_namelen	= xprt->addrlen,
 941		.msg_flags	= XS_SENDMSG_FLAGS,
 942	};
 943	unsigned int sent;
 944	int status;
 945
 946	xs_pktdump("packet data:",
 947				req->rq_svec->iov_base,
 948				req->rq_svec->iov_len);
 949
 950	if (!xprt_bound(xprt))
 951		return -ENOTCONN;
 952
 953	if (!xprt_request_get_cong(xprt, req))
 954		return -EBADSLT;
 955
 956	status = xdr_alloc_bvec(xdr, rpc_task_gfp_mask());
 957	if (status < 0)
 958		return status;
 959	req->rq_xtime = ktime_get();
 960	status = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, 0, &sent);
 961
 962	dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
 963			xdr->len, status);
 964
 965	/* firewall is blocking us, don't return -EAGAIN or we end up looping */
 966	if (status == -EPERM)
 967		goto process_status;
 968
 969	if (status == -EAGAIN && sock_writeable(transport->inet))
 970		status = -ENOBUFS;
 971
 972	if (sent > 0 || status == 0) {
 973		req->rq_xmit_bytes_sent += sent;
 974		if (sent >= req->rq_slen)
 975			return 0;
 976		/* Still some bytes left; set up for a retry later. */
 977		status = -EAGAIN;
 978	}
 979
 980process_status:
 981	switch (status) {
 982	case -ENOTSOCK:
 983		status = -ENOTCONN;
 984		/* Should we call xs_close() here? */
 985		break;
 986	case -EAGAIN:
 987		status = xs_sock_nospace(req);
 988		break;
 989	case -ENETUNREACH:
 990	case -ENOBUFS:
 991	case -EPIPE:
 992	case -ECONNREFUSED:
 993	case -EPERM:
 994		/* When the server has died, an ICMP port unreachable message
 995		 * prompts ECONNREFUSED. */
 996		break;
 997	default:
 998		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 999			-status);
1000	}
1001
1002	return status;
1003}
1004
1005/**
1006 * xs_tcp_send_request - write an RPC request to a TCP socket
1007 * @req: pointer to RPC request
1008 *
1009 * Return values:
1010 *        0:	The request has been sent
1011 *   EAGAIN:	The socket was blocked, please call again later to
1012 *		complete the request
1013 * ENOTCONN:	Caller needs to invoke connect logic then call again
1014 *    other:	Some other error occurred, the request was not sent
1015 *
1016 * XXX: In the case of soft timeouts, should we eventually give up
1017 *	if sendmsg is not able to make progress?
1018 */
1019static int xs_tcp_send_request(struct rpc_rqst *req)
1020{
1021	struct rpc_xprt *xprt = req->rq_xprt;
1022	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1023	struct xdr_buf *xdr = &req->rq_snd_buf;
1024	rpc_fraghdr rm = xs_stream_record_marker(xdr);
1025	unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
1026	struct msghdr msg = {
1027		.msg_flags	= XS_SENDMSG_FLAGS,
1028	};
1029	bool vm_wait;
1030	unsigned int sent;
1031	int status;
1032
1033	/* Close the stream if the previous transmission was incomplete */
1034	if (xs_send_request_was_aborted(transport, req)) {
1035		if (transport->sock != NULL)
1036			kernel_sock_shutdown(transport->sock, SHUT_RDWR);
1037		return -ENOTCONN;
1038	}
1039	if (!transport->inet)
1040		return -ENOTCONN;
1041
1042	xs_pktdump("packet data:",
1043				req->rq_svec->iov_base,
1044				req->rq_svec->iov_len);
1045
1046	if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state))
1047		xs_tcp_set_socket_timeouts(xprt, transport->sock);
1048
1049	xs_set_srcport(transport, transport->sock);
1050
1051	/* Continue transmitting the packet/record. We must be careful
1052	 * to cope with writespace callbacks arriving _after_ we have
1053	 * called sendmsg(). */
1054	req->rq_xtime = ktime_get();
1055	tcp_sock_set_cork(transport->inet, true);
1056
1057	vm_wait = sk_stream_is_writeable(transport->inet) ? true : false;
1058
1059	do {
1060		status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
1061					   transport->xmit.offset, rm, &sent);
1062
1063		dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
1064				xdr->len - transport->xmit.offset, status);
1065
1066		/* If we've sent the entire packet, immediately
1067		 * reset the count of bytes sent. */
1068		transport->xmit.offset += sent;
1069		req->rq_bytes_sent = transport->xmit.offset;
1070		if (likely(req->rq_bytes_sent >= msglen)) {
1071			req->rq_xmit_bytes_sent += transport->xmit.offset;
1072			transport->xmit.offset = 0;
1073			if (atomic_long_read(&xprt->xmit_queuelen) == 1)
1074				tcp_sock_set_cork(transport->inet, false);
1075			return 0;
1076		}
1077
1078		WARN_ON_ONCE(sent == 0 && status == 0);
1079
1080		if (sent > 0)
1081			vm_wait = false;
1082
1083	} while (status == 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1084
1085	switch (status) {
1086	case -ENOTSOCK:
1087		status = -ENOTCONN;
1088		/* Should we call xs_close() here? */
1089		break;
1090	case -EAGAIN:
1091		status = xs_stream_nospace(req, vm_wait);
1092		break;
1093	case -ECONNRESET:
1094	case -ECONNREFUSED:
1095	case -ENOTCONN:
1096	case -EADDRINUSE:
1097	case -ENOBUFS:
1098	case -EPIPE:
1099		break;
1100	default:
1101		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1102			-status);
1103	}
1104
1105	return status;
1106}
1107
1108static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1109{
1110	transport->old_data_ready = sk->sk_data_ready;
1111	transport->old_state_change = sk->sk_state_change;
1112	transport->old_write_space = sk->sk_write_space;
1113	transport->old_error_report = sk->sk_error_report;
1114}
1115
1116static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1117{
1118	sk->sk_data_ready = transport->old_data_ready;
1119	sk->sk_state_change = transport->old_state_change;
1120	sk->sk_write_space = transport->old_write_space;
1121	sk->sk_error_report = transport->old_error_report;
1122}
1123
1124static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
1125{
1126	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1127
1128	clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1129	clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state);
1130	clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state);
1131	clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state);
1132	clear_bit(XPRT_SOCK_NOSPACE, &transport->sock_state);
1133}
1134
1135static void xs_run_error_worker(struct sock_xprt *transport, unsigned int nr)
1136{
1137	set_bit(nr, &transport->sock_state);
1138	queue_work(xprtiod_workqueue, &transport->error_worker);
1139}
1140
1141static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
1142{
1143	xprt->connect_cookie++;
1144	smp_mb__before_atomic();
1145	clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1146	clear_bit(XPRT_CLOSING, &xprt->state);
1147	xs_sock_reset_state_flags(xprt);
1148	smp_mb__after_atomic();
1149}
1150
1151/**
1152 * xs_error_report - callback to handle TCP socket state errors
1153 * @sk: socket
1154 *
1155 * Note: we don't call sock_error() since there may be a rpc_task
1156 * using the socket, and so we don't want to clear sk->sk_err.
1157 */
1158static void xs_error_report(struct sock *sk)
1159{
1160	struct sock_xprt *transport;
1161	struct rpc_xprt *xprt;
1162
 
1163	if (!(xprt = xprt_from_sock(sk)))
1164		return;
1165
1166	transport = container_of(xprt, struct sock_xprt, xprt);
1167	transport->xprt_err = -sk->sk_err;
1168	if (transport->xprt_err == 0)
1169		return;
1170	dprintk("RPC:       xs_error_report client %p, error=%d...\n",
1171			xprt, -transport->xprt_err);
1172	trace_rpc_socket_error(xprt, sk->sk_socket, transport->xprt_err);
1173
1174	/* barrier ensures xprt_err is set before XPRT_SOCK_WAKE_ERROR */
1175	smp_mb__before_atomic();
1176	xs_run_error_worker(transport, XPRT_SOCK_WAKE_ERROR);
 
 
1177}
1178
1179static void xs_reset_transport(struct sock_xprt *transport)
1180{
1181	struct socket *sock = transport->sock;
1182	struct sock *sk = transport->inet;
1183	struct rpc_xprt *xprt = &transport->xprt;
1184	struct file *filp = transport->file;
1185
1186	if (sk == NULL)
1187		return;
1188	/*
1189	 * Make sure we're calling this in a context from which it is safe
1190	 * to call __fput_sync(). In practice that means rpciod and the
1191	 * system workqueue.
1192	 */
1193	if (!(current->flags & PF_WQ_WORKER)) {
1194		WARN_ON_ONCE(1);
1195		set_bit(XPRT_CLOSE_WAIT, &xprt->state);
1196		return;
1197	}
1198
1199	if (atomic_read(&transport->xprt.swapper))
1200		sk_clear_memalloc(sk);
1201
1202	kernel_sock_shutdown(sock, SHUT_RDWR);
1203
1204	mutex_lock(&transport->recv_mutex);
1205	lock_sock(sk);
1206	transport->inet = NULL;
1207	transport->sock = NULL;
1208	transport->file = NULL;
1209
1210	sk->sk_user_data = NULL;
1211
1212	xs_restore_old_callbacks(transport, sk);
1213	xprt_clear_connected(xprt);
 
1214	xs_sock_reset_connection_flags(xprt);
1215	/* Reset stream record info */
1216	xs_stream_reset_connect(transport);
1217	release_sock(sk);
1218	mutex_unlock(&transport->recv_mutex);
1219
1220	trace_rpc_socket_close(xprt, sock);
1221	__fput_sync(filp);
1222
1223	xprt_disconnect_done(xprt);
1224}
1225
1226/**
1227 * xs_close - close a socket
1228 * @xprt: transport
1229 *
1230 * This is used when all requests are complete; ie, no DRC state remains
1231 * on the server we want to save.
1232 *
1233 * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
1234 * xs_reset_transport() zeroing the socket from underneath a writer.
1235 */
1236static void xs_close(struct rpc_xprt *xprt)
1237{
1238	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1239
1240	dprintk("RPC:       xs_close xprt %p\n", xprt);
1241
1242	xs_reset_transport(transport);
1243	xprt->reestablish_timeout = 0;
1244}
1245
1246static void xs_inject_disconnect(struct rpc_xprt *xprt)
1247{
1248	dprintk("RPC:       injecting transport disconnect on xprt=%p\n",
1249		xprt);
1250	xprt_disconnect_done(xprt);
1251}
1252
1253static void xs_xprt_free(struct rpc_xprt *xprt)
1254{
1255	xs_free_peer_addresses(xprt);
1256	xprt_free(xprt);
1257}
1258
1259/**
1260 * xs_destroy - prepare to shutdown a transport
1261 * @xprt: doomed transport
1262 *
1263 */
1264static void xs_destroy(struct rpc_xprt *xprt)
1265{
1266	struct sock_xprt *transport = container_of(xprt,
1267			struct sock_xprt, xprt);
1268	dprintk("RPC:       xs_destroy xprt %p\n", xprt);
1269
1270	cancel_delayed_work_sync(&transport->connect_worker);
1271	xs_close(xprt);
1272	cancel_work_sync(&transport->recv_worker);
1273	cancel_work_sync(&transport->error_worker);
1274	xs_xprt_free(xprt);
1275	module_put(THIS_MODULE);
1276}
1277
1278/**
1279 * xs_udp_data_read_skb - receive callback for UDP sockets
1280 * @xprt: transport
1281 * @sk: socket
1282 * @skb: skbuff
1283 *
1284 */
1285static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
1286		struct sock *sk,
1287		struct sk_buff *skb)
1288{
1289	struct rpc_task *task;
1290	struct rpc_rqst *rovr;
1291	int repsize, copied;
1292	u32 _xid;
1293	__be32 *xp;
1294
1295	repsize = skb->len;
1296	if (repsize < 4) {
1297		dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
1298		return;
1299	}
1300
1301	/* Copy the XID from the skb... */
1302	xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
1303	if (xp == NULL)
1304		return;
1305
1306	/* Look up and lock the request corresponding to the given XID */
1307	spin_lock(&xprt->queue_lock);
1308	rovr = xprt_lookup_rqst(xprt, *xp);
1309	if (!rovr)
1310		goto out_unlock;
1311	xprt_pin_rqst(rovr);
1312	xprt_update_rtt(rovr->rq_task);
1313	spin_unlock(&xprt->queue_lock);
1314	task = rovr->rq_task;
1315
1316	if ((copied = rovr->rq_private_buf.buflen) > repsize)
1317		copied = repsize;
1318
1319	/* Suck it into the iovec, verify checksum if not done by hw. */
1320	if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1321		spin_lock(&xprt->queue_lock);
1322		__UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
1323		goto out_unpin;
1324	}
1325
1326
1327	spin_lock(&xprt->transport_lock);
1328	xprt_adjust_cwnd(xprt, task, copied);
1329	spin_unlock(&xprt->transport_lock);
1330	spin_lock(&xprt->queue_lock);
1331	xprt_complete_rqst(task, copied);
1332	__UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
1333out_unpin:
1334	xprt_unpin_rqst(rovr);
1335 out_unlock:
1336	spin_unlock(&xprt->queue_lock);
1337}
1338
1339static void xs_udp_data_receive(struct sock_xprt *transport)
1340{
1341	struct sk_buff *skb;
1342	struct sock *sk;
1343	int err;
1344
1345	mutex_lock(&transport->recv_mutex);
1346	sk = transport->inet;
1347	if (sk == NULL)
1348		goto out;
1349	for (;;) {
1350		skb = skb_recv_udp(sk, MSG_DONTWAIT, &err);
1351		if (skb == NULL)
1352			break;
1353		xs_udp_data_read_skb(&transport->xprt, sk, skb);
1354		consume_skb(skb);
1355		cond_resched();
1356	}
1357	xs_poll_check_readable(transport);
1358out:
1359	mutex_unlock(&transport->recv_mutex);
1360}
1361
1362static void xs_udp_data_receive_workfn(struct work_struct *work)
1363{
1364	struct sock_xprt *transport =
1365		container_of(work, struct sock_xprt, recv_worker);
1366	unsigned int pflags = memalloc_nofs_save();
1367
1368	xs_udp_data_receive(transport);
1369	memalloc_nofs_restore(pflags);
1370}
1371
1372/**
1373 * xs_data_ready - "data ready" callback for sockets
1374 * @sk: socket with data to read
1375 *
1376 */
1377static void xs_data_ready(struct sock *sk)
1378{
1379	struct rpc_xprt *xprt;
1380
 
 
1381	xprt = xprt_from_sock(sk);
1382	if (xprt != NULL) {
1383		struct sock_xprt *transport = container_of(xprt,
1384				struct sock_xprt, xprt);
1385
1386		trace_xs_data_ready(xprt);
1387
1388		transport->old_data_ready(sk);
1389		/* Any data means we had a useful conversation, so
1390		 * then we don't need to delay the next reconnect
1391		 */
1392		if (xprt->reestablish_timeout)
1393			xprt->reestablish_timeout = 0;
1394		if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1395			queue_work(xprtiod_workqueue, &transport->recv_worker);
1396	}
 
1397}
1398
1399/*
1400 * Helper function to force a TCP close if the server is sending
1401 * junk and/or it has put us in CLOSE_WAIT
1402 */
1403static void xs_tcp_force_close(struct rpc_xprt *xprt)
1404{
1405	xprt_force_disconnect(xprt);
1406}
1407
1408#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1409static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
1410{
1411	return PAGE_SIZE;
1412}
1413#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1414
1415/**
1416 * xs_local_state_change - callback to handle AF_LOCAL socket state changes
1417 * @sk: socket whose state has changed
1418 *
1419 */
1420static void xs_local_state_change(struct sock *sk)
1421{
1422	struct rpc_xprt *xprt;
1423	struct sock_xprt *transport;
1424
1425	if (!(xprt = xprt_from_sock(sk)))
1426		return;
1427	transport = container_of(xprt, struct sock_xprt, xprt);
1428	if (sk->sk_shutdown & SHUTDOWN_MASK) {
1429		clear_bit(XPRT_CONNECTED, &xprt->state);
1430		/* Trigger the socket release */
1431		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1432	}
1433}
1434
1435/**
1436 * xs_tcp_state_change - callback to handle TCP socket state changes
1437 * @sk: socket whose state has changed
1438 *
1439 */
1440static void xs_tcp_state_change(struct sock *sk)
1441{
1442	struct rpc_xprt *xprt;
1443	struct sock_xprt *transport;
1444
 
1445	if (!(xprt = xprt_from_sock(sk)))
1446		return;
1447	dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1448	dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1449			sk->sk_state, xprt_connected(xprt),
1450			sock_flag(sk, SOCK_DEAD),
1451			sock_flag(sk, SOCK_ZAPPED),
1452			sk->sk_shutdown);
1453
1454	transport = container_of(xprt, struct sock_xprt, xprt);
1455	trace_rpc_socket_state_change(xprt, sk->sk_socket);
1456	switch (sk->sk_state) {
1457	case TCP_ESTABLISHED:
1458		if (!xprt_test_and_set_connected(xprt)) {
1459			xprt->connect_cookie++;
1460			clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
1461			xprt_clear_connecting(xprt);
1462
1463			xprt->stat.connect_count++;
1464			xprt->stat.connect_time += (long)jiffies -
1465						   xprt->stat.connect_start;
1466			xs_run_error_worker(transport, XPRT_SOCK_WAKE_PENDING);
1467		}
1468		break;
1469	case TCP_FIN_WAIT1:
1470		/* The client initiated a shutdown of the socket */
1471		xprt->connect_cookie++;
1472		xprt->reestablish_timeout = 0;
1473		set_bit(XPRT_CLOSING, &xprt->state);
1474		smp_mb__before_atomic();
1475		clear_bit(XPRT_CONNECTED, &xprt->state);
1476		clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1477		smp_mb__after_atomic();
1478		break;
1479	case TCP_CLOSE_WAIT:
1480		/* The server initiated a shutdown of the socket */
1481		xprt->connect_cookie++;
1482		clear_bit(XPRT_CONNECTED, &xprt->state);
1483		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1484		fallthrough;
1485	case TCP_CLOSING:
1486		/*
1487		 * If the server closed down the connection, make sure that
1488		 * we back off before reconnecting
1489		 */
1490		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1491			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1492		break;
1493	case TCP_LAST_ACK:
1494		set_bit(XPRT_CLOSING, &xprt->state);
1495		smp_mb__before_atomic();
1496		clear_bit(XPRT_CONNECTED, &xprt->state);
1497		smp_mb__after_atomic();
1498		break;
1499	case TCP_CLOSE:
1500		if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
1501					&transport->sock_state))
1502			xprt_clear_connecting(xprt);
1503		clear_bit(XPRT_CLOSING, &xprt->state);
1504		/* Trigger the socket release */
1505		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1506	}
 
 
1507}
1508
1509static void xs_write_space(struct sock *sk)
1510{
 
1511	struct sock_xprt *transport;
1512	struct rpc_xprt *xprt;
1513
1514	if (!sk->sk_socket)
1515		return;
1516	clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1517
1518	if (unlikely(!(xprt = xprt_from_sock(sk))))
1519		return;
1520	transport = container_of(xprt, struct sock_xprt, xprt);
1521	if (!test_and_clear_bit(XPRT_SOCK_NOSPACE, &transport->sock_state))
1522		return;
 
 
 
1523	xs_run_error_worker(transport, XPRT_SOCK_WAKE_WRITE);
1524	sk->sk_write_pending--;
 
 
1525}
1526
1527/**
1528 * xs_udp_write_space - callback invoked when socket buffer space
1529 *                             becomes available
1530 * @sk: socket whose state has changed
1531 *
1532 * Called when more output buffer space is available for this socket.
1533 * We try not to wake our writers until they can make "significant"
1534 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1535 * with a bunch of small requests.
1536 */
1537static void xs_udp_write_space(struct sock *sk)
1538{
 
 
1539	/* from net/core/sock.c:sock_def_write_space */
1540	if (sock_writeable(sk))
1541		xs_write_space(sk);
 
 
1542}
1543
1544/**
1545 * xs_tcp_write_space - callback invoked when socket buffer space
1546 *                             becomes available
1547 * @sk: socket whose state has changed
1548 *
1549 * Called when more output buffer space is available for this socket.
1550 * We try not to wake our writers until they can make "significant"
1551 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1552 * with a bunch of small requests.
1553 */
1554static void xs_tcp_write_space(struct sock *sk)
1555{
 
 
1556	/* from net/core/stream.c:sk_stream_write_space */
1557	if (sk_stream_is_writeable(sk))
1558		xs_write_space(sk);
 
 
1559}
1560
1561static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1562{
1563	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1564	struct sock *sk = transport->inet;
1565
1566	if (transport->rcvsize) {
1567		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1568		sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1569	}
1570	if (transport->sndsize) {
1571		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1572		sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1573		sk->sk_write_space(sk);
1574	}
1575}
1576
1577/**
1578 * xs_udp_set_buffer_size - set send and receive limits
1579 * @xprt: generic transport
1580 * @sndsize: requested size of send buffer, in bytes
1581 * @rcvsize: requested size of receive buffer, in bytes
1582 *
1583 * Set socket send and receive buffer size limits.
1584 */
1585static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1586{
1587	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1588
1589	transport->sndsize = 0;
1590	if (sndsize)
1591		transport->sndsize = sndsize + 1024;
1592	transport->rcvsize = 0;
1593	if (rcvsize)
1594		transport->rcvsize = rcvsize + 1024;
1595
1596	xs_udp_do_set_buffer_size(xprt);
1597}
1598
1599/**
1600 * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1601 * @xprt: controlling transport
1602 * @task: task that timed out
1603 *
1604 * Adjust the congestion window after a retransmit timeout has occurred.
1605 */
1606static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1607{
1608	spin_lock(&xprt->transport_lock);
1609	xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1610	spin_unlock(&xprt->transport_lock);
1611}
1612
1613static int xs_get_random_port(void)
1614{
1615	unsigned short min = xprt_min_resvport, max = xprt_max_resvport;
1616	unsigned short range;
1617	unsigned short rand;
1618
1619	if (max < min)
1620		return -EADDRINUSE;
1621	range = max - min + 1;
1622	rand = get_random_u32_below(range);
1623	return rand + min;
1624}
1625
1626static unsigned short xs_sock_getport(struct socket *sock)
1627{
1628	struct sockaddr_storage buf;
1629	unsigned short port = 0;
1630
1631	if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0)
1632		goto out;
1633	switch (buf.ss_family) {
1634	case AF_INET6:
1635		port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1636		break;
1637	case AF_INET:
1638		port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1639	}
1640out:
1641	return port;
1642}
1643
1644/**
1645 * xs_set_port - reset the port number in the remote endpoint address
1646 * @xprt: generic transport
1647 * @port: new port number
1648 *
1649 */
1650static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1651{
1652	dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1653
1654	rpc_set_port(xs_addr(xprt), port);
1655	xs_update_peer_port(xprt);
1656}
1657
1658static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1659{
1660	if (transport->srcport == 0 && transport->xprt.reuseport)
1661		transport->srcport = xs_sock_getport(sock);
1662}
1663
1664static int xs_get_srcport(struct sock_xprt *transport)
1665{
1666	int port = transport->srcport;
1667
1668	if (port == 0 && transport->xprt.resvport)
1669		port = xs_get_random_port();
1670	return port;
1671}
1672
1673static unsigned short xs_sock_srcport(struct rpc_xprt *xprt)
1674{
1675	struct sock_xprt *sock = container_of(xprt, struct sock_xprt, xprt);
1676	unsigned short ret = 0;
1677	mutex_lock(&sock->recv_mutex);
1678	if (sock->sock)
1679		ret = xs_sock_getport(sock->sock);
1680	mutex_unlock(&sock->recv_mutex);
1681	return ret;
1682}
1683
1684static int xs_sock_srcaddr(struct rpc_xprt *xprt, char *buf, size_t buflen)
1685{
1686	struct sock_xprt *sock = container_of(xprt, struct sock_xprt, xprt);
1687	union {
1688		struct sockaddr sa;
1689		struct sockaddr_storage st;
1690	} saddr;
1691	int ret = -ENOTCONN;
1692
1693	mutex_lock(&sock->recv_mutex);
1694	if (sock->sock) {
1695		ret = kernel_getsockname(sock->sock, &saddr.sa);
1696		if (ret >= 0)
1697			ret = snprintf(buf, buflen, "%pISc", &saddr.sa);
1698	}
1699	mutex_unlock(&sock->recv_mutex);
1700	return ret;
1701}
 
1702
1703static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1704{
1705	if (transport->srcport != 0)
1706		transport->srcport = 0;
1707	if (!transport->xprt.resvport)
1708		return 0;
1709	if (port <= xprt_min_resvport || port > xprt_max_resvport)
1710		return xprt_max_resvport;
1711	return --port;
1712}
1713static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1714{
1715	struct sockaddr_storage myaddr;
1716	int err, nloop = 0;
1717	int port = xs_get_srcport(transport);
1718	unsigned short last;
1719
1720	/*
1721	 * If we are asking for any ephemeral port (i.e. port == 0 &&
1722	 * transport->xprt.resvport == 0), don't bind.  Let the local
1723	 * port selection happen implicitly when the socket is used
1724	 * (for example at connect time).
1725	 *
1726	 * This ensures that we can continue to establish TCP
1727	 * connections even when all local ephemeral ports are already
1728	 * a part of some TCP connection.  This makes no difference
1729	 * for UDP sockets, but also doesn't harm them.
1730	 *
1731	 * If we're asking for any reserved port (i.e. port == 0 &&
1732	 * transport->xprt.resvport == 1) xs_get_srcport above will
1733	 * ensure that port is non-zero and we will bind as needed.
1734	 */
1735	if (port <= 0)
1736		return port;
1737
1738	memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1739	do {
1740		rpc_set_port((struct sockaddr *)&myaddr, port);
1741		err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1742				transport->xprt.addrlen);
1743		if (err == 0) {
1744			if (transport->xprt.reuseport)
1745				transport->srcport = port;
1746			break;
1747		}
1748		last = port;
1749		port = xs_next_srcport(transport, port);
1750		if (port > last)
1751			nloop++;
1752	} while (err == -EADDRINUSE && nloop != 2);
1753
1754	if (myaddr.ss_family == AF_INET)
1755		dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1756				&((struct sockaddr_in *)&myaddr)->sin_addr,
1757				port, err ? "failed" : "ok", err);
1758	else
1759		dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1760				&((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1761				port, err ? "failed" : "ok", err);
1762	return err;
1763}
1764
1765/*
1766 * We don't support autobind on AF_LOCAL sockets
1767 */
1768static void xs_local_rpcbind(struct rpc_task *task)
1769{
1770	xprt_set_bound(task->tk_xprt);
1771}
1772
1773static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1774{
1775}
1776
1777#ifdef CONFIG_DEBUG_LOCK_ALLOC
1778static struct lock_class_key xs_key[3];
1779static struct lock_class_key xs_slock_key[3];
1780
1781static inline void xs_reclassify_socketu(struct socket *sock)
1782{
1783	struct sock *sk = sock->sk;
1784
1785	sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1786		&xs_slock_key[0], "sk_lock-AF_LOCAL-RPC", &xs_key[0]);
1787}
1788
1789static inline void xs_reclassify_socket4(struct socket *sock)
1790{
1791	struct sock *sk = sock->sk;
1792
1793	sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1794		&xs_slock_key[1], "sk_lock-AF_INET-RPC", &xs_key[1]);
1795}
1796
1797static inline void xs_reclassify_socket6(struct socket *sock)
1798{
1799	struct sock *sk = sock->sk;
1800
1801	sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1802		&xs_slock_key[2], "sk_lock-AF_INET6-RPC", &xs_key[2]);
1803}
1804
1805static inline void xs_reclassify_socket(int family, struct socket *sock)
1806{
1807	if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
1808		return;
1809
1810	switch (family) {
1811	case AF_LOCAL:
1812		xs_reclassify_socketu(sock);
1813		break;
1814	case AF_INET:
1815		xs_reclassify_socket4(sock);
1816		break;
1817	case AF_INET6:
1818		xs_reclassify_socket6(sock);
1819		break;
1820	}
1821}
1822#else
1823static inline void xs_reclassify_socket(int family, struct socket *sock)
1824{
1825}
1826#endif
1827
1828static void xs_dummy_setup_socket(struct work_struct *work)
1829{
1830}
1831
1832static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1833		struct sock_xprt *transport, int family, int type,
1834		int protocol, bool reuseport)
1835{
1836	struct file *filp;
1837	struct socket *sock;
1838	int err;
1839
1840	err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1841	if (err < 0) {
1842		dprintk("RPC:       can't create %d transport socket (%d).\n",
1843				protocol, -err);
1844		goto out;
1845	}
1846	xs_reclassify_socket(family, sock);
1847
1848	if (reuseport)
1849		sock_set_reuseport(sock->sk);
1850
1851	err = xs_bind(transport, sock);
1852	if (err) {
1853		sock_release(sock);
1854		goto out;
1855	}
1856
1857	filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1858	if (IS_ERR(filp))
1859		return ERR_CAST(filp);
1860	transport->file = filp;
1861
1862	return sock;
1863out:
1864	return ERR_PTR(err);
1865}
1866
1867static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1868				      struct socket *sock)
1869{
1870	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1871									xprt);
1872
1873	if (!transport->inet) {
1874		struct sock *sk = sock->sk;
1875
1876		lock_sock(sk);
1877
1878		xs_save_old_callbacks(transport, sk);
1879
1880		sk->sk_user_data = xprt;
1881		sk->sk_data_ready = xs_data_ready;
1882		sk->sk_write_space = xs_udp_write_space;
1883		sk->sk_state_change = xs_local_state_change;
1884		sk->sk_error_report = xs_error_report;
1885		sk->sk_use_task_frag = false;
1886
1887		xprt_clear_connected(xprt);
1888
1889		/* Reset to new socket */
1890		transport->sock = sock;
1891		transport->inet = sk;
1892
1893		release_sock(sk);
1894	}
1895
1896	xs_stream_start_connect(transport);
1897
1898	return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1899}
1900
1901/**
1902 * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1903 * @transport: socket transport to connect
1904 */
1905static int xs_local_setup_socket(struct sock_xprt *transport)
1906{
1907	struct rpc_xprt *xprt = &transport->xprt;
1908	struct file *filp;
1909	struct socket *sock;
1910	int status;
1911
1912	status = __sock_create(xprt->xprt_net, AF_LOCAL,
1913					SOCK_STREAM, 0, &sock, 1);
1914	if (status < 0) {
1915		dprintk("RPC:       can't create AF_LOCAL "
1916			"transport socket (%d).\n", -status);
1917		goto out;
1918	}
1919	xs_reclassify_socket(AF_LOCAL, sock);
1920
1921	filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1922	if (IS_ERR(filp)) {
1923		status = PTR_ERR(filp);
1924		goto out;
1925	}
1926	transport->file = filp;
1927
1928	dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
1929			xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1930
1931	status = xs_local_finish_connecting(xprt, sock);
1932	trace_rpc_socket_connect(xprt, sock, status);
1933	switch (status) {
1934	case 0:
1935		dprintk("RPC:       xprt %p connected to %s\n",
1936				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1937		xprt->stat.connect_count++;
1938		xprt->stat.connect_time += (long)jiffies -
1939					   xprt->stat.connect_start;
1940		xprt_set_connected(xprt);
1941		break;
1942	case -ENOBUFS:
1943		break;
1944	case -ENOENT:
1945		dprintk("RPC:       xprt %p: socket %s does not exist\n",
1946				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1947		break;
1948	case -ECONNREFUSED:
1949		dprintk("RPC:       xprt %p: connection refused for %s\n",
1950				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1951		break;
1952	default:
1953		printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
1954				__func__, -status,
1955				xprt->address_strings[RPC_DISPLAY_ADDR]);
1956	}
1957
1958out:
1959	xprt_clear_connecting(xprt);
1960	xprt_wake_pending_tasks(xprt, status);
1961	return status;
1962}
1963
1964static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
1965{
1966	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1967	int ret;
1968
1969	if (transport->file)
1970		goto force_disconnect;
1971
1972	if (RPC_IS_ASYNC(task)) {
1973		/*
1974		 * We want the AF_LOCAL connect to be resolved in the
1975		 * filesystem namespace of the process making the rpc
1976		 * call.  Thus we connect synchronously.
1977		 *
1978		 * If we want to support asynchronous AF_LOCAL calls,
1979		 * we'll need to figure out how to pass a namespace to
1980		 * connect.
1981		 */
1982		rpc_task_set_rpc_status(task, -ENOTCONN);
1983		goto out_wake;
 
1984	}
1985	ret = xs_local_setup_socket(transport);
1986	if (ret && !RPC_IS_SOFTCONN(task))
1987		msleep_interruptible(15000);
1988	return;
1989force_disconnect:
1990	xprt_force_disconnect(xprt);
1991out_wake:
1992	xprt_clear_connecting(xprt);
1993	xprt_wake_pending_tasks(xprt, -ENOTCONN);
1994}
1995
1996#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
1997/*
1998 * Note that this should be called with XPRT_LOCKED held, or recv_mutex
1999 * held, or when we otherwise know that we have exclusive access to the
2000 * socket, to guard against races with xs_reset_transport.
2001 */
2002static void xs_set_memalloc(struct rpc_xprt *xprt)
2003{
2004	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
2005			xprt);
2006
2007	/*
2008	 * If there's no sock, then we have nothing to set. The
2009	 * reconnecting process will get it for us.
2010	 */
2011	if (!transport->inet)
2012		return;
2013	if (atomic_read(&xprt->swapper))
2014		sk_set_memalloc(transport->inet);
2015}
2016
2017/**
2018 * xs_enable_swap - Tag this transport as being used for swap.
2019 * @xprt: transport to tag
2020 *
2021 * Take a reference to this transport on behalf of the rpc_clnt, and
2022 * optionally mark it for swapping if it wasn't already.
2023 */
2024static int
2025xs_enable_swap(struct rpc_xprt *xprt)
2026{
2027	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2028
2029	mutex_lock(&xs->recv_mutex);
2030	if (atomic_inc_return(&xprt->swapper) == 1 &&
2031	    xs->inet)
 
 
2032		sk_set_memalloc(xs->inet);
2033	mutex_unlock(&xs->recv_mutex);
2034	return 0;
2035}
2036
2037/**
2038 * xs_disable_swap - Untag this transport as being used for swap.
2039 * @xprt: transport to tag
2040 *
2041 * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
2042 * swapper refcount goes to 0, untag the socket as a memalloc socket.
2043 */
2044static void
2045xs_disable_swap(struct rpc_xprt *xprt)
2046{
2047	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2048
2049	mutex_lock(&xs->recv_mutex);
2050	if (atomic_dec_and_test(&xprt->swapper) &&
2051	    xs->inet)
 
 
2052		sk_clear_memalloc(xs->inet);
2053	mutex_unlock(&xs->recv_mutex);
2054}
2055#else
2056static void xs_set_memalloc(struct rpc_xprt *xprt)
2057{
2058}
2059
2060static int
2061xs_enable_swap(struct rpc_xprt *xprt)
2062{
2063	return -EINVAL;
2064}
2065
2066static void
2067xs_disable_swap(struct rpc_xprt *xprt)
2068{
2069}
2070#endif
2071
2072static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2073{
2074	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2075
2076	if (!transport->inet) {
2077		struct sock *sk = sock->sk;
2078
2079		lock_sock(sk);
2080
2081		xs_save_old_callbacks(transport, sk);
2082
2083		sk->sk_user_data = xprt;
2084		sk->sk_data_ready = xs_data_ready;
2085		sk->sk_write_space = xs_udp_write_space;
2086		sk->sk_use_task_frag = false;
2087
2088		xprt_set_connected(xprt);
2089
2090		/* Reset to new socket */
2091		transport->sock = sock;
2092		transport->inet = sk;
2093
2094		xs_set_memalloc(xprt);
2095
2096		release_sock(sk);
2097	}
2098	xs_udp_do_set_buffer_size(xprt);
2099
2100	xprt->stat.connect_start = jiffies;
2101}
2102
2103static void xs_udp_setup_socket(struct work_struct *work)
2104{
2105	struct sock_xprt *transport =
2106		container_of(work, struct sock_xprt, connect_worker.work);
2107	struct rpc_xprt *xprt = &transport->xprt;
2108	struct socket *sock;
2109	int status = -EIO;
2110	unsigned int pflags = current->flags;
2111
2112	if (atomic_read(&xprt->swapper))
2113		current->flags |= PF_MEMALLOC;
2114	sock = xs_create_sock(xprt, transport,
2115			xs_addr(xprt)->sa_family, SOCK_DGRAM,
2116			IPPROTO_UDP, false);
2117	if (IS_ERR(sock))
2118		goto out;
2119
2120	dprintk("RPC:       worker connecting xprt %p via %s to "
2121				"%s (port %s)\n", xprt,
2122			xprt->address_strings[RPC_DISPLAY_PROTO],
2123			xprt->address_strings[RPC_DISPLAY_ADDR],
2124			xprt->address_strings[RPC_DISPLAY_PORT]);
2125
2126	xs_udp_finish_connecting(xprt, sock);
2127	trace_rpc_socket_connect(xprt, sock, 0);
2128	status = 0;
2129out:
2130	xprt_clear_connecting(xprt);
2131	xprt_unlock_connect(xprt, transport);
2132	xprt_wake_pending_tasks(xprt, status);
2133	current_restore_flags(pflags, PF_MEMALLOC);
2134}
2135
2136/**
2137 * xs_tcp_shutdown - gracefully shut down a TCP socket
2138 * @xprt: transport
2139 *
2140 * Initiates a graceful shutdown of the TCP socket by calling the
2141 * equivalent of shutdown(SHUT_RDWR);
2142 */
2143static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2144{
2145	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2146	struct socket *sock = transport->sock;
2147	int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
2148
2149	if (sock == NULL)
2150		return;
2151	if (!xprt->reuseport) {
2152		xs_close(xprt);
2153		return;
2154	}
2155	switch (skst) {
2156	case TCP_FIN_WAIT1:
2157	case TCP_FIN_WAIT2:
2158		break;
2159	case TCP_ESTABLISHED:
2160	case TCP_CLOSE_WAIT:
2161		kernel_sock_shutdown(sock, SHUT_RDWR);
2162		trace_rpc_socket_shutdown(xprt, sock);
2163		break;
2164	default:
 
2165		xs_reset_transport(transport);
2166	}
2167}
2168
2169static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
2170		struct socket *sock)
2171{
2172	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2173	unsigned int keepidle;
2174	unsigned int keepcnt;
2175	unsigned int timeo;
2176
2177	spin_lock(&xprt->transport_lock);
2178	keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
2179	keepcnt = xprt->timeout->to_retries + 1;
2180	timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2181		(xprt->timeout->to_retries + 1);
2182	clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2183	spin_unlock(&xprt->transport_lock);
2184
2185	/* TCP Keepalive options */
2186	sock_set_keepalive(sock->sk);
2187	tcp_sock_set_keepidle(sock->sk, keepidle);
2188	tcp_sock_set_keepintvl(sock->sk, keepidle);
2189	tcp_sock_set_keepcnt(sock->sk, keepcnt);
2190
2191	/* TCP user timeout (see RFC5482) */
2192	tcp_sock_set_user_timeout(sock->sk, timeo);
2193}
2194
2195static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
2196		unsigned long connect_timeout,
2197		unsigned long reconnect_timeout)
2198{
2199	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2200	struct rpc_timeout to;
2201	unsigned long initval;
2202
2203	spin_lock(&xprt->transport_lock);
2204	if (reconnect_timeout < xprt->max_reconnect_timeout)
2205		xprt->max_reconnect_timeout = reconnect_timeout;
2206	if (connect_timeout < xprt->connect_timeout) {
2207		memcpy(&to, xprt->timeout, sizeof(to));
2208		initval = DIV_ROUND_UP(connect_timeout, to.to_retries + 1);
2209		/* Arbitrary lower limit */
2210		if (initval <  XS_TCP_INIT_REEST_TO << 1)
2211			initval = XS_TCP_INIT_REEST_TO << 1;
2212		to.to_initval = initval;
2213		to.to_maxval = initval;
2214		memcpy(&transport->tcp_timeout, &to,
2215				sizeof(transport->tcp_timeout));
2216		xprt->timeout = &transport->tcp_timeout;
2217		xprt->connect_timeout = connect_timeout;
2218	}
2219	set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2220	spin_unlock(&xprt->transport_lock);
2221}
2222
2223static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2224{
2225	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 
2226
2227	if (!transport->inet) {
2228		struct sock *sk = sock->sk;
2229
2230		/* Avoid temporary address, they are bad for long-lived
2231		 * connections such as NFS mounts.
2232		 * RFC4941, section 3.6 suggests that:
2233		 *    Individual applications, which have specific
2234		 *    knowledge about the normal duration of connections,
2235		 *    MAY override this as appropriate.
2236		 */
2237		if (xs_addr(xprt)->sa_family == PF_INET6) {
2238			ip6_sock_set_addr_preferences(sk,
2239				IPV6_PREFER_SRC_PUBLIC);
2240		}
2241
2242		xs_tcp_set_socket_timeouts(xprt, sock);
2243		tcp_sock_set_nodelay(sk);
2244
2245		lock_sock(sk);
2246
2247		xs_save_old_callbacks(transport, sk);
2248
2249		sk->sk_user_data = xprt;
2250		sk->sk_data_ready = xs_data_ready;
2251		sk->sk_state_change = xs_tcp_state_change;
2252		sk->sk_write_space = xs_tcp_write_space;
 
2253		sk->sk_error_report = xs_error_report;
2254		sk->sk_use_task_frag = false;
2255
2256		/* socket options */
2257		sock_reset_flag(sk, SOCK_LINGER);
2258
2259		xprt_clear_connected(xprt);
2260
2261		/* Reset to new socket */
2262		transport->sock = sock;
2263		transport->inet = sk;
2264
2265		release_sock(sk);
2266	}
2267
2268	if (!xprt_bound(xprt))
2269		return -ENOTCONN;
2270
2271	xs_set_memalloc(xprt);
2272
2273	xs_stream_start_connect(transport);
2274
2275	/* Tell the socket layer to start connecting... */
2276	set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2277	return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2278}
2279
2280/**
2281 * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2282 * @work: queued work item
2283 *
2284 * Invoked by a work queue tasklet.
2285 */
2286static void xs_tcp_setup_socket(struct work_struct *work)
2287{
2288	struct sock_xprt *transport =
2289		container_of(work, struct sock_xprt, connect_worker.work);
2290	struct socket *sock = transport->sock;
2291	struct rpc_xprt *xprt = &transport->xprt;
2292	int status;
2293	unsigned int pflags = current->flags;
2294
2295	if (atomic_read(&xprt->swapper))
2296		current->flags |= PF_MEMALLOC;
2297
2298	if (xprt_connected(xprt))
2299		goto out;
2300	if (test_and_clear_bit(XPRT_SOCK_CONNECT_SENT,
2301			       &transport->sock_state) ||
2302	    !sock) {
2303		xs_reset_transport(transport);
2304		sock = xs_create_sock(xprt, transport, xs_addr(xprt)->sa_family,
2305				      SOCK_STREAM, IPPROTO_TCP, true);
2306		if (IS_ERR(sock)) {
2307			xprt_wake_pending_tasks(xprt, PTR_ERR(sock));
2308			goto out;
2309		}
2310	}
2311
2312	dprintk("RPC:       worker connecting xprt %p via %s to "
2313				"%s (port %s)\n", xprt,
2314			xprt->address_strings[RPC_DISPLAY_PROTO],
2315			xprt->address_strings[RPC_DISPLAY_ADDR],
2316			xprt->address_strings[RPC_DISPLAY_PORT]);
2317
2318	status = xs_tcp_finish_connecting(xprt, sock);
2319	trace_rpc_socket_connect(xprt, sock, status);
2320	dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2321			xprt, -status, xprt_connected(xprt),
2322			sock->sk->sk_state);
2323	switch (status) {
2324	case 0:
2325	case -EINPROGRESS:
2326		/* SYN_SENT! */
2327		set_bit(XPRT_SOCK_CONNECT_SENT, &transport->sock_state);
2328		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2329			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2330		fallthrough;
2331	case -EALREADY:
2332		goto out_unlock;
2333	case -EADDRNOTAVAIL:
2334		/* Source port number is unavailable. Try a new one! */
2335		transport->srcport = 0;
2336		status = -EAGAIN;
 
2337		break;
 
 
 
 
 
2338	case -EINVAL:
2339		/* Happens, for instance, if the user specified a link
2340		 * local IPv6 address without a scope-id.
2341		 */
2342	case -ECONNREFUSED:
2343	case -ECONNRESET:
2344	case -ENETDOWN:
2345	case -ENETUNREACH:
2346	case -EHOSTUNREACH:
2347	case -EADDRINUSE:
2348	case -ENOBUFS:
2349		break;
2350	default:
2351		printk("%s: connect returned unhandled error %d\n",
2352			__func__, status);
2353		status = -EAGAIN;
 
2354	}
2355
2356	/* xs_tcp_force_close() wakes tasks with a fixed error code.
2357	 * We need to wake them first to ensure the correct error code.
2358	 */
2359	xprt_wake_pending_tasks(xprt, status);
2360	xs_tcp_force_close(xprt);
2361out:
2362	xprt_clear_connecting(xprt);
2363out_unlock:
2364	xprt_unlock_connect(xprt, transport);
2365	current_restore_flags(pflags, PF_MEMALLOC);
2366}
2367
2368/**
2369 * xs_connect - connect a socket to a remote endpoint
2370 * @xprt: pointer to transport structure
2371 * @task: address of RPC task that manages state of connect request
2372 *
2373 * TCP: If the remote end dropped the connection, delay reconnecting.
2374 *
2375 * UDP socket connects are synchronous, but we use a work queue anyway
2376 * to guarantee that even unprivileged user processes can set up a
2377 * socket on a privileged port.
2378 *
2379 * If a UDP socket connect fails, the delay behavior here prevents
2380 * retry floods (hard mounts).
2381 */
2382static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2383{
2384	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2385	unsigned long delay = 0;
2386
2387	WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2388
2389	if (transport->sock != NULL) {
2390		dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2391			"seconds\n", xprt, xprt->reestablish_timeout / HZ);
 
 
 
 
2392
2393		delay = xprt_reconnect_delay(xprt);
2394		xprt_reconnect_backoff(xprt, XS_TCP_INIT_REEST_TO);
2395
2396	} else
2397		dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2398
2399	queue_delayed_work(xprtiod_workqueue,
2400			&transport->connect_worker,
2401			delay);
2402}
2403
2404static void xs_wake_disconnect(struct sock_xprt *transport)
2405{
2406	if (test_and_clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state))
2407		xs_tcp_force_close(&transport->xprt);
2408}
2409
2410static void xs_wake_write(struct sock_xprt *transport)
2411{
2412	if (test_and_clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state))
2413		xprt_write_space(&transport->xprt);
2414}
2415
2416static void xs_wake_error(struct sock_xprt *transport)
2417{
2418	int sockerr;
2419
2420	if (!test_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2421		return;
2422	mutex_lock(&transport->recv_mutex);
2423	if (transport->sock == NULL)
2424		goto out;
2425	if (!test_and_clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2426		goto out;
2427	sockerr = xchg(&transport->xprt_err, 0);
2428	if (sockerr < 0)
2429		xprt_wake_pending_tasks(&transport->xprt, sockerr);
2430out:
2431	mutex_unlock(&transport->recv_mutex);
2432}
2433
2434static void xs_wake_pending(struct sock_xprt *transport)
2435{
2436	if (test_and_clear_bit(XPRT_SOCK_WAKE_PENDING, &transport->sock_state))
2437		xprt_wake_pending_tasks(&transport->xprt, -EAGAIN);
2438}
2439
2440static void xs_error_handle(struct work_struct *work)
2441{
2442	struct sock_xprt *transport = container_of(work,
2443			struct sock_xprt, error_worker);
2444
2445	xs_wake_disconnect(transport);
2446	xs_wake_write(transport);
2447	xs_wake_error(transport);
2448	xs_wake_pending(transport);
2449}
2450
2451/**
2452 * xs_local_print_stats - display AF_LOCAL socket-specific stats
2453 * @xprt: rpc_xprt struct containing statistics
2454 * @seq: output file
2455 *
2456 */
2457static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2458{
2459	long idle_time = 0;
2460
2461	if (xprt_connected(xprt))
2462		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2463
2464	seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2465			"%llu %llu %lu %llu %llu\n",
2466			xprt->stat.bind_count,
2467			xprt->stat.connect_count,
2468			xprt->stat.connect_time / HZ,
2469			idle_time,
2470			xprt->stat.sends,
2471			xprt->stat.recvs,
2472			xprt->stat.bad_xids,
2473			xprt->stat.req_u,
2474			xprt->stat.bklog_u,
2475			xprt->stat.max_slots,
2476			xprt->stat.sending_u,
2477			xprt->stat.pending_u);
2478}
2479
2480/**
2481 * xs_udp_print_stats - display UDP socket-specific stats
2482 * @xprt: rpc_xprt struct containing statistics
2483 * @seq: output file
2484 *
2485 */
2486static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2487{
2488	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2489
2490	seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2491			"%lu %llu %llu\n",
2492			transport->srcport,
2493			xprt->stat.bind_count,
2494			xprt->stat.sends,
2495			xprt->stat.recvs,
2496			xprt->stat.bad_xids,
2497			xprt->stat.req_u,
2498			xprt->stat.bklog_u,
2499			xprt->stat.max_slots,
2500			xprt->stat.sending_u,
2501			xprt->stat.pending_u);
2502}
2503
2504/**
2505 * xs_tcp_print_stats - display TCP socket-specific stats
2506 * @xprt: rpc_xprt struct containing statistics
2507 * @seq: output file
2508 *
2509 */
2510static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2511{
2512	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2513	long idle_time = 0;
2514
2515	if (xprt_connected(xprt))
2516		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2517
2518	seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2519			"%llu %llu %lu %llu %llu\n",
2520			transport->srcport,
2521			xprt->stat.bind_count,
2522			xprt->stat.connect_count,
2523			xprt->stat.connect_time / HZ,
2524			idle_time,
2525			xprt->stat.sends,
2526			xprt->stat.recvs,
2527			xprt->stat.bad_xids,
2528			xprt->stat.req_u,
2529			xprt->stat.bklog_u,
2530			xprt->stat.max_slots,
2531			xprt->stat.sending_u,
2532			xprt->stat.pending_u);
2533}
2534
2535/*
2536 * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2537 * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2538 * to use the server side send routines.
2539 */
2540static int bc_malloc(struct rpc_task *task)
2541{
2542	struct rpc_rqst *rqst = task->tk_rqstp;
2543	size_t size = rqst->rq_callsize;
2544	struct page *page;
2545	struct rpc_buffer *buf;
2546
2547	if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2548		WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2549			  size);
2550		return -EINVAL;
2551	}
2552
2553	page = alloc_page(GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
2554	if (!page)
2555		return -ENOMEM;
2556
2557	buf = page_address(page);
2558	buf->len = PAGE_SIZE;
2559
2560	rqst->rq_buffer = buf->data;
2561	rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2562	return 0;
2563}
2564
2565/*
2566 * Free the space allocated in the bc_alloc routine
2567 */
2568static void bc_free(struct rpc_task *task)
2569{
2570	void *buffer = task->tk_rqstp->rq_buffer;
2571	struct rpc_buffer *buf;
2572
2573	buf = container_of(buffer, struct rpc_buffer, data);
2574	free_page((unsigned long)buf);
2575}
2576
2577static int bc_sendto(struct rpc_rqst *req)
2578{
2579	struct xdr_buf *xdr = &req->rq_snd_buf;
2580	struct sock_xprt *transport =
2581			container_of(req->rq_xprt, struct sock_xprt, xprt);
2582	struct msghdr msg = {
2583		.msg_flags	= 0,
2584	};
2585	rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT |
2586					 (u32)xdr->len);
2587	unsigned int sent = 0;
2588	int err;
2589
2590	req->rq_xtime = ktime_get();
2591	err = xdr_alloc_bvec(xdr, rpc_task_gfp_mask());
2592	if (err < 0)
2593		return err;
2594	err = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, marker, &sent);
2595	xdr_free_bvec(xdr);
2596	if (err < 0 || sent != (xdr->len + sizeof(marker)))
2597		return -EAGAIN;
2598	return sent;
2599}
2600
2601/**
2602 * bc_send_request - Send a backchannel Call on a TCP socket
2603 * @req: rpc_rqst containing Call message to be sent
2604 *
2605 * xpt_mutex ensures @rqstp's whole message is written to the socket
2606 * without interruption.
2607 *
2608 * Return values:
2609 *   %0 if the message was sent successfully
2610 *   %ENOTCONN if the message was not sent
2611 */
2612static int bc_send_request(struct rpc_rqst *req)
2613{
2614	struct svc_xprt	*xprt;
2615	int len;
2616
2617	/*
2618	 * Get the server socket associated with this callback xprt
2619	 */
2620	xprt = req->rq_xprt->bc_xprt;
2621
2622	/*
2623	 * Grab the mutex to serialize data as the connection is shared
2624	 * with the fore channel
2625	 */
2626	mutex_lock(&xprt->xpt_mutex);
2627	if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2628		len = -ENOTCONN;
2629	else
2630		len = bc_sendto(req);
2631	mutex_unlock(&xprt->xpt_mutex);
2632
2633	if (len > 0)
2634		len = 0;
2635
2636	return len;
2637}
2638
2639/*
2640 * The close routine. Since this is client initiated, we do nothing
2641 */
2642
2643static void bc_close(struct rpc_xprt *xprt)
2644{
2645	xprt_disconnect_done(xprt);
2646}
2647
2648/*
2649 * The xprt destroy routine. Again, because this connection is client
2650 * initiated, we do nothing
2651 */
2652
2653static void bc_destroy(struct rpc_xprt *xprt)
2654{
2655	dprintk("RPC:       bc_destroy xprt %p\n", xprt);
2656
2657	xs_xprt_free(xprt);
2658	module_put(THIS_MODULE);
2659}
2660
2661static const struct rpc_xprt_ops xs_local_ops = {
2662	.reserve_xprt		= xprt_reserve_xprt,
2663	.release_xprt		= xprt_release_xprt,
2664	.alloc_slot		= xprt_alloc_slot,
2665	.free_slot		= xprt_free_slot,
2666	.rpcbind		= xs_local_rpcbind,
2667	.set_port		= xs_local_set_port,
2668	.connect		= xs_local_connect,
2669	.buf_alloc		= rpc_malloc,
2670	.buf_free		= rpc_free,
2671	.prepare_request	= xs_stream_prepare_request,
2672	.send_request		= xs_local_send_request,
2673	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
2674	.close			= xs_close,
2675	.destroy		= xs_destroy,
2676	.print_stats		= xs_local_print_stats,
2677	.enable_swap		= xs_enable_swap,
2678	.disable_swap		= xs_disable_swap,
2679};
2680
2681static const struct rpc_xprt_ops xs_udp_ops = {
2682	.set_buffer_size	= xs_udp_set_buffer_size,
2683	.reserve_xprt		= xprt_reserve_xprt_cong,
2684	.release_xprt		= xprt_release_xprt_cong,
2685	.alloc_slot		= xprt_alloc_slot,
2686	.free_slot		= xprt_free_slot,
2687	.rpcbind		= rpcb_getport_async,
2688	.set_port		= xs_set_port,
2689	.connect		= xs_connect,
2690	.get_srcaddr		= xs_sock_srcaddr,
2691	.get_srcport		= xs_sock_srcport,
2692	.buf_alloc		= rpc_malloc,
2693	.buf_free		= rpc_free,
2694	.send_request		= xs_udp_send_request,
2695	.wait_for_reply_request	= xprt_wait_for_reply_request_rtt,
2696	.timer			= xs_udp_timer,
2697	.release_request	= xprt_release_rqst_cong,
2698	.close			= xs_close,
2699	.destroy		= xs_destroy,
2700	.print_stats		= xs_udp_print_stats,
2701	.enable_swap		= xs_enable_swap,
2702	.disable_swap		= xs_disable_swap,
2703	.inject_disconnect	= xs_inject_disconnect,
2704};
2705
2706static const struct rpc_xprt_ops xs_tcp_ops = {
2707	.reserve_xprt		= xprt_reserve_xprt,
2708	.release_xprt		= xprt_release_xprt,
2709	.alloc_slot		= xprt_alloc_slot,
2710	.free_slot		= xprt_free_slot,
2711	.rpcbind		= rpcb_getport_async,
2712	.set_port		= xs_set_port,
2713	.connect		= xs_connect,
2714	.get_srcaddr		= xs_sock_srcaddr,
2715	.get_srcport		= xs_sock_srcport,
2716	.buf_alloc		= rpc_malloc,
2717	.buf_free		= rpc_free,
2718	.prepare_request	= xs_stream_prepare_request,
2719	.send_request		= xs_tcp_send_request,
2720	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
2721	.close			= xs_tcp_shutdown,
2722	.destroy		= xs_destroy,
2723	.set_connect_timeout	= xs_tcp_set_connect_timeout,
2724	.print_stats		= xs_tcp_print_stats,
2725	.enable_swap		= xs_enable_swap,
2726	.disable_swap		= xs_disable_swap,
2727	.inject_disconnect	= xs_inject_disconnect,
2728#ifdef CONFIG_SUNRPC_BACKCHANNEL
2729	.bc_setup		= xprt_setup_bc,
2730	.bc_maxpayload		= xs_tcp_bc_maxpayload,
2731	.bc_num_slots		= xprt_bc_max_slots,
2732	.bc_free_rqst		= xprt_free_bc_rqst,
2733	.bc_destroy		= xprt_destroy_bc,
2734#endif
2735};
2736
2737/*
2738 * The rpc_xprt_ops for the server backchannel
2739 */
2740
2741static const struct rpc_xprt_ops bc_tcp_ops = {
2742	.reserve_xprt		= xprt_reserve_xprt,
2743	.release_xprt		= xprt_release_xprt,
2744	.alloc_slot		= xprt_alloc_slot,
2745	.free_slot		= xprt_free_slot,
2746	.buf_alloc		= bc_malloc,
2747	.buf_free		= bc_free,
2748	.send_request		= bc_send_request,
2749	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
2750	.close			= bc_close,
2751	.destroy		= bc_destroy,
2752	.print_stats		= xs_tcp_print_stats,
2753	.enable_swap		= xs_enable_swap,
2754	.disable_swap		= xs_disable_swap,
2755	.inject_disconnect	= xs_inject_disconnect,
2756};
2757
2758static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2759{
2760	static const struct sockaddr_in sin = {
2761		.sin_family		= AF_INET,
2762		.sin_addr.s_addr	= htonl(INADDR_ANY),
2763	};
2764	static const struct sockaddr_in6 sin6 = {
2765		.sin6_family		= AF_INET6,
2766		.sin6_addr		= IN6ADDR_ANY_INIT,
2767	};
2768
2769	switch (family) {
2770	case AF_LOCAL:
2771		break;
2772	case AF_INET:
2773		memcpy(sap, &sin, sizeof(sin));
2774		break;
2775	case AF_INET6:
2776		memcpy(sap, &sin6, sizeof(sin6));
2777		break;
2778	default:
2779		dprintk("RPC:       %s: Bad address family\n", __func__);
2780		return -EAFNOSUPPORT;
2781	}
2782	return 0;
2783}
2784
2785static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2786				      unsigned int slot_table_size,
2787				      unsigned int max_slot_table_size)
2788{
2789	struct rpc_xprt *xprt;
2790	struct sock_xprt *new;
2791
2792	if (args->addrlen > sizeof(xprt->addr)) {
2793		dprintk("RPC:       xs_setup_xprt: address too large\n");
2794		return ERR_PTR(-EBADF);
2795	}
2796
2797	xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2798			max_slot_table_size);
2799	if (xprt == NULL) {
2800		dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2801				"rpc_xprt\n");
2802		return ERR_PTR(-ENOMEM);
2803	}
2804
2805	new = container_of(xprt, struct sock_xprt, xprt);
2806	mutex_init(&new->recv_mutex);
2807	memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2808	xprt->addrlen = args->addrlen;
2809	if (args->srcaddr)
2810		memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2811	else {
2812		int err;
2813		err = xs_init_anyaddr(args->dstaddr->sa_family,
2814					(struct sockaddr *)&new->srcaddr);
2815		if (err != 0) {
2816			xprt_free(xprt);
2817			return ERR_PTR(err);
2818		}
2819	}
2820
2821	return xprt;
2822}
2823
2824static const struct rpc_timeout xs_local_default_timeout = {
2825	.to_initval = 10 * HZ,
2826	.to_maxval = 10 * HZ,
2827	.to_retries = 2,
2828};
2829
2830/**
2831 * xs_setup_local - Set up transport to use an AF_LOCAL socket
2832 * @args: rpc transport creation arguments
2833 *
2834 * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2835 */
2836static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2837{
2838	struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2839	struct sock_xprt *transport;
2840	struct rpc_xprt *xprt;
2841	struct rpc_xprt *ret;
2842
2843	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2844			xprt_max_tcp_slot_table_entries);
2845	if (IS_ERR(xprt))
2846		return xprt;
2847	transport = container_of(xprt, struct sock_xprt, xprt);
2848
2849	xprt->prot = 0;
2850	xprt->xprt_class = &xs_local_transport;
2851	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2852
2853	xprt->bind_timeout = XS_BIND_TO;
2854	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2855	xprt->idle_timeout = XS_IDLE_DISC_TO;
2856
2857	xprt->ops = &xs_local_ops;
2858	xprt->timeout = &xs_local_default_timeout;
2859
2860	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2861	INIT_WORK(&transport->error_worker, xs_error_handle);
2862	INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket);
2863
2864	switch (sun->sun_family) {
2865	case AF_LOCAL:
2866		if (sun->sun_path[0] != '/') {
2867			dprintk("RPC:       bad AF_LOCAL address: %s\n",
2868					sun->sun_path);
2869			ret = ERR_PTR(-EINVAL);
2870			goto out_err;
2871		}
2872		xprt_set_bound(xprt);
2873		xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
 
 
 
2874		break;
2875	default:
2876		ret = ERR_PTR(-EAFNOSUPPORT);
2877		goto out_err;
2878	}
2879
2880	dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
2881			xprt->address_strings[RPC_DISPLAY_ADDR]);
2882
2883	if (try_module_get(THIS_MODULE))
2884		return xprt;
2885	ret = ERR_PTR(-EINVAL);
2886out_err:
2887	xs_xprt_free(xprt);
2888	return ret;
2889}
2890
2891static const struct rpc_timeout xs_udp_default_timeout = {
2892	.to_initval = 5 * HZ,
2893	.to_maxval = 30 * HZ,
2894	.to_increment = 5 * HZ,
2895	.to_retries = 5,
2896};
2897
2898/**
2899 * xs_setup_udp - Set up transport to use a UDP socket
2900 * @args: rpc transport creation arguments
2901 *
2902 */
2903static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2904{
2905	struct sockaddr *addr = args->dstaddr;
2906	struct rpc_xprt *xprt;
2907	struct sock_xprt *transport;
2908	struct rpc_xprt *ret;
2909
2910	xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2911			xprt_udp_slot_table_entries);
2912	if (IS_ERR(xprt))
2913		return xprt;
2914	transport = container_of(xprt, struct sock_xprt, xprt);
2915
2916	xprt->prot = IPPROTO_UDP;
2917	xprt->xprt_class = &xs_udp_transport;
2918	/* XXX: header size can vary due to auth type, IPv6, etc. */
2919	xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2920
2921	xprt->bind_timeout = XS_BIND_TO;
2922	xprt->reestablish_timeout = XS_UDP_REEST_TO;
2923	xprt->idle_timeout = XS_IDLE_DISC_TO;
2924
2925	xprt->ops = &xs_udp_ops;
2926
2927	xprt->timeout = &xs_udp_default_timeout;
2928
2929	INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
2930	INIT_WORK(&transport->error_worker, xs_error_handle);
2931	INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
2932
2933	switch (addr->sa_family) {
2934	case AF_INET:
2935		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2936			xprt_set_bound(xprt);
2937
2938		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2939		break;
2940	case AF_INET6:
2941		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2942			xprt_set_bound(xprt);
2943
2944		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2945		break;
2946	default:
2947		ret = ERR_PTR(-EAFNOSUPPORT);
2948		goto out_err;
2949	}
2950
2951	if (xprt_bound(xprt))
2952		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2953				xprt->address_strings[RPC_DISPLAY_ADDR],
2954				xprt->address_strings[RPC_DISPLAY_PORT],
2955				xprt->address_strings[RPC_DISPLAY_PROTO]);
2956	else
2957		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2958				xprt->address_strings[RPC_DISPLAY_ADDR],
2959				xprt->address_strings[RPC_DISPLAY_PROTO]);
2960
2961	if (try_module_get(THIS_MODULE))
2962		return xprt;
2963	ret = ERR_PTR(-EINVAL);
2964out_err:
2965	xs_xprt_free(xprt);
2966	return ret;
2967}
2968
2969static const struct rpc_timeout xs_tcp_default_timeout = {
2970	.to_initval = 60 * HZ,
2971	.to_maxval = 60 * HZ,
2972	.to_retries = 2,
2973};
2974
2975/**
2976 * xs_setup_tcp - Set up transport to use a TCP socket
2977 * @args: rpc transport creation arguments
2978 *
2979 */
2980static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2981{
2982	struct sockaddr *addr = args->dstaddr;
2983	struct rpc_xprt *xprt;
2984	struct sock_xprt *transport;
2985	struct rpc_xprt *ret;
2986	unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
2987
2988	if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
2989		max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
2990
2991	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2992			max_slot_table_size);
2993	if (IS_ERR(xprt))
2994		return xprt;
2995	transport = container_of(xprt, struct sock_xprt, xprt);
2996
2997	xprt->prot = IPPROTO_TCP;
2998	xprt->xprt_class = &xs_tcp_transport;
2999	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3000
3001	xprt->bind_timeout = XS_BIND_TO;
3002	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
3003	xprt->idle_timeout = XS_IDLE_DISC_TO;
3004
3005	xprt->ops = &xs_tcp_ops;
3006	xprt->timeout = &xs_tcp_default_timeout;
3007
3008	xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
3009	xprt->connect_timeout = xprt->timeout->to_initval *
3010		(xprt->timeout->to_retries + 1);
3011
3012	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
3013	INIT_WORK(&transport->error_worker, xs_error_handle);
3014	INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
3015
3016	switch (addr->sa_family) {
3017	case AF_INET:
3018		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3019			xprt_set_bound(xprt);
3020
3021		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
3022		break;
3023	case AF_INET6:
3024		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3025			xprt_set_bound(xprt);
3026
3027		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
3028		break;
3029	default:
3030		ret = ERR_PTR(-EAFNOSUPPORT);
3031		goto out_err;
3032	}
3033
3034	if (xprt_bound(xprt))
3035		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3036				xprt->address_strings[RPC_DISPLAY_ADDR],
3037				xprt->address_strings[RPC_DISPLAY_PORT],
3038				xprt->address_strings[RPC_DISPLAY_PROTO]);
3039	else
3040		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3041				xprt->address_strings[RPC_DISPLAY_ADDR],
3042				xprt->address_strings[RPC_DISPLAY_PROTO]);
3043
3044	if (try_module_get(THIS_MODULE))
3045		return xprt;
3046	ret = ERR_PTR(-EINVAL);
3047out_err:
3048	xs_xprt_free(xprt);
3049	return ret;
3050}
3051
3052/**
3053 * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
3054 * @args: rpc transport creation arguments
3055 *
3056 */
3057static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
3058{
3059	struct sockaddr *addr = args->dstaddr;
3060	struct rpc_xprt *xprt;
3061	struct sock_xprt *transport;
3062	struct svc_sock *bc_sock;
3063	struct rpc_xprt *ret;
3064
3065	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3066			xprt_tcp_slot_table_entries);
3067	if (IS_ERR(xprt))
3068		return xprt;
3069	transport = container_of(xprt, struct sock_xprt, xprt);
3070
3071	xprt->prot = IPPROTO_TCP;
3072	xprt->xprt_class = &xs_bc_tcp_transport;
3073	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3074	xprt->timeout = &xs_tcp_default_timeout;
3075
3076	/* backchannel */
3077	xprt_set_bound(xprt);
3078	xprt->bind_timeout = 0;
3079	xprt->reestablish_timeout = 0;
3080	xprt->idle_timeout = 0;
3081
3082	xprt->ops = &bc_tcp_ops;
3083
3084	switch (addr->sa_family) {
3085	case AF_INET:
3086		xs_format_peer_addresses(xprt, "tcp",
3087					 RPCBIND_NETID_TCP);
3088		break;
3089	case AF_INET6:
3090		xs_format_peer_addresses(xprt, "tcp",
3091				   RPCBIND_NETID_TCP6);
3092		break;
3093	default:
3094		ret = ERR_PTR(-EAFNOSUPPORT);
3095		goto out_err;
3096	}
3097
3098	dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3099			xprt->address_strings[RPC_DISPLAY_ADDR],
3100			xprt->address_strings[RPC_DISPLAY_PORT],
3101			xprt->address_strings[RPC_DISPLAY_PROTO]);
3102
3103	/*
3104	 * Once we've associated a backchannel xprt with a connection,
3105	 * we want to keep it around as long as the connection lasts,
3106	 * in case we need to start using it for a backchannel again;
3107	 * this reference won't be dropped until bc_xprt is destroyed.
3108	 */
3109	xprt_get(xprt);
3110	args->bc_xprt->xpt_bc_xprt = xprt;
3111	xprt->bc_xprt = args->bc_xprt;
3112	bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3113	transport->sock = bc_sock->sk_sock;
3114	transport->inet = bc_sock->sk_sk;
3115
3116	/*
3117	 * Since we don't want connections for the backchannel, we set
3118	 * the xprt status to connected
3119	 */
3120	xprt_set_connected(xprt);
3121
3122	if (try_module_get(THIS_MODULE))
3123		return xprt;
3124
3125	args->bc_xprt->xpt_bc_xprt = NULL;
3126	args->bc_xprt->xpt_bc_xps = NULL;
3127	xprt_put(xprt);
3128	ret = ERR_PTR(-EINVAL);
3129out_err:
3130	xs_xprt_free(xprt);
3131	return ret;
3132}
3133
3134static struct xprt_class	xs_local_transport = {
3135	.list		= LIST_HEAD_INIT(xs_local_transport.list),
3136	.name		= "named UNIX socket",
3137	.owner		= THIS_MODULE,
3138	.ident		= XPRT_TRANSPORT_LOCAL,
3139	.setup		= xs_setup_local,
3140	.netid		= { "" },
3141};
3142
3143static struct xprt_class	xs_udp_transport = {
3144	.list		= LIST_HEAD_INIT(xs_udp_transport.list),
3145	.name		= "udp",
3146	.owner		= THIS_MODULE,
3147	.ident		= XPRT_TRANSPORT_UDP,
3148	.setup		= xs_setup_udp,
3149	.netid		= { "udp", "udp6", "" },
3150};
3151
3152static struct xprt_class	xs_tcp_transport = {
3153	.list		= LIST_HEAD_INIT(xs_tcp_transport.list),
3154	.name		= "tcp",
3155	.owner		= THIS_MODULE,
3156	.ident		= XPRT_TRANSPORT_TCP,
3157	.setup		= xs_setup_tcp,
3158	.netid		= { "tcp", "tcp6", "" },
3159};
3160
3161static struct xprt_class	xs_bc_tcp_transport = {
3162	.list		= LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3163	.name		= "tcp NFSv4.1 backchannel",
3164	.owner		= THIS_MODULE,
3165	.ident		= XPRT_TRANSPORT_BC_TCP,
3166	.setup		= xs_setup_bc_tcp,
3167	.netid		= { "" },
3168};
3169
3170/**
3171 * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3172 *
3173 */
3174int init_socket_xprt(void)
3175{
3176	if (!sunrpc_table_header)
3177		sunrpc_table_header = register_sysctl_table(sunrpc_table);
3178
3179	xprt_register_transport(&xs_local_transport);
3180	xprt_register_transport(&xs_udp_transport);
3181	xprt_register_transport(&xs_tcp_transport);
3182	xprt_register_transport(&xs_bc_tcp_transport);
3183
3184	return 0;
3185}
3186
3187/**
3188 * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3189 *
3190 */
3191void cleanup_socket_xprt(void)
3192{
3193	if (sunrpc_table_header) {
3194		unregister_sysctl_table(sunrpc_table_header);
3195		sunrpc_table_header = NULL;
3196	}
3197
3198	xprt_unregister_transport(&xs_local_transport);
3199	xprt_unregister_transport(&xs_udp_transport);
3200	xprt_unregister_transport(&xs_tcp_transport);
3201	xprt_unregister_transport(&xs_bc_tcp_transport);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3202}
3203
3204static int param_set_portnr(const char *val, const struct kernel_param *kp)
3205{
3206	return param_set_uint_minmax(val, kp,
3207			RPC_MIN_RESVPORT,
3208			RPC_MAX_RESVPORT);
3209}
3210
3211static const struct kernel_param_ops param_ops_portnr = {
3212	.set = param_set_portnr,
3213	.get = param_get_uint,
3214};
3215
3216#define param_check_portnr(name, p) \
3217	__param_check(name, p, unsigned int);
3218
3219module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3220module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3221
3222static int param_set_slot_table_size(const char *val,
3223				     const struct kernel_param *kp)
3224{
3225	return param_set_uint_minmax(val, kp,
3226			RPC_MIN_SLOT_TABLE,
3227			RPC_MAX_SLOT_TABLE);
3228}
3229
3230static const struct kernel_param_ops param_ops_slot_table_size = {
3231	.set = param_set_slot_table_size,
3232	.get = param_get_uint,
3233};
3234
3235#define param_check_slot_table_size(name, p) \
3236	__param_check(name, p, unsigned int);
3237
3238static int param_set_max_slot_table_size(const char *val,
3239				     const struct kernel_param *kp)
3240{
3241	return param_set_uint_minmax(val, kp,
3242			RPC_MIN_SLOT_TABLE,
3243			RPC_MAX_SLOT_TABLE_LIMIT);
3244}
3245
3246static const struct kernel_param_ops param_ops_max_slot_table_size = {
3247	.set = param_set_max_slot_table_size,
3248	.get = param_get_uint,
3249};
3250
3251#define param_check_max_slot_table_size(name, p) \
3252	__param_check(name, p, unsigned int);
3253
3254module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3255		   slot_table_size, 0644);
3256module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3257		   max_slot_table_size, 0644);
3258module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3259		   slot_table_size, 0644);
v5.14.15
   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
  94static struct xprt_class xs_local_transport;
  95static struct xprt_class xs_udp_transport;
  96static struct xprt_class xs_tcp_transport;
  97static struct xprt_class xs_bc_tcp_transport;
  98
  99/*
 100 * FIXME: changing the UDP slot table size should also resize the UDP
 101 *        socket buffers for existing UDP transports
 102 */
 103static struct ctl_table xs_tunables_table[] = {
 104	{
 105		.procname	= "udp_slot_table_entries",
 106		.data		= &xprt_udp_slot_table_entries,
 107		.maxlen		= sizeof(unsigned int),
 108		.mode		= 0644,
 109		.proc_handler	= proc_dointvec_minmax,
 110		.extra1		= &min_slot_table_size,
 111		.extra2		= &max_slot_table_size
 112	},
 113	{
 114		.procname	= "tcp_slot_table_entries",
 115		.data		= &xprt_tcp_slot_table_entries,
 116		.maxlen		= sizeof(unsigned int),
 117		.mode		= 0644,
 118		.proc_handler	= proc_dointvec_minmax,
 119		.extra1		= &min_slot_table_size,
 120		.extra2		= &max_slot_table_size
 121	},
 122	{
 123		.procname	= "tcp_max_slot_table_entries",
 124		.data		= &xprt_max_tcp_slot_table_entries,
 125		.maxlen		= sizeof(unsigned int),
 126		.mode		= 0644,
 127		.proc_handler	= proc_dointvec_minmax,
 128		.extra1		= &min_slot_table_size,
 129		.extra2		= &max_tcp_slot_table_limit
 130	},
 131	{
 132		.procname	= "min_resvport",
 133		.data		= &xprt_min_resvport,
 134		.maxlen		= sizeof(unsigned int),
 135		.mode		= 0644,
 136		.proc_handler	= proc_dointvec_minmax,
 137		.extra1		= &xprt_min_resvport_limit,
 138		.extra2		= &xprt_max_resvport_limit
 139	},
 140	{
 141		.procname	= "max_resvport",
 142		.data		= &xprt_max_resvport,
 143		.maxlen		= sizeof(unsigned int),
 144		.mode		= 0644,
 145		.proc_handler	= proc_dointvec_minmax,
 146		.extra1		= &xprt_min_resvport_limit,
 147		.extra2		= &xprt_max_resvport_limit
 148	},
 149	{
 150		.procname	= "tcp_fin_timeout",
 151		.data		= &xs_tcp_fin_timeout,
 152		.maxlen		= sizeof(xs_tcp_fin_timeout),
 153		.mode		= 0644,
 154		.proc_handler	= proc_dointvec_jiffies,
 155	},
 156	{ },
 157};
 158
 159static struct ctl_table sunrpc_table[] = {
 160	{
 161		.procname	= "sunrpc",
 162		.mode		= 0555,
 163		.child		= xs_tunables_table
 164	},
 165	{ },
 166};
 167
 168/*
 169 * Wait duration for a reply from the RPC portmapper.
 170 */
 171#define XS_BIND_TO		(60U * HZ)
 172
 173/*
 174 * Delay if a UDP socket connect error occurs.  This is most likely some
 175 * kind of resource problem on the local host.
 176 */
 177#define XS_UDP_REEST_TO		(2U * HZ)
 178
 179/*
 180 * The reestablish timeout allows clients to delay for a bit before attempting
 181 * to reconnect to a server that just dropped our connection.
 182 *
 183 * We implement an exponential backoff when trying to reestablish a TCP
 184 * transport connection with the server.  Some servers like to drop a TCP
 185 * connection when they are overworked, so we start with a short timeout and
 186 * increase over time if the server is down or not responding.
 187 */
 188#define XS_TCP_INIT_REEST_TO	(3U * HZ)
 189
 190/*
 191 * TCP idle timeout; client drops the transport socket if it is idle
 192 * for this long.  Note that we also timeout UDP sockets to prevent
 193 * holding port numbers when there is no RPC traffic.
 194 */
 195#define XS_IDLE_DISC_TO		(5U * 60 * HZ)
 196
 197#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 198# undef  RPC_DEBUG_DATA
 199# define RPCDBG_FACILITY	RPCDBG_TRANS
 200#endif
 201
 202#ifdef RPC_DEBUG_DATA
 203static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 204{
 205	u8 *buf = (u8 *) packet;
 206	int j;
 207
 208	dprintk("RPC:       %s\n", msg);
 209	for (j = 0; j < count && j < 128; j += 4) {
 210		if (!(j & 31)) {
 211			if (j)
 212				dprintk("\n");
 213			dprintk("0x%04x ", j);
 214		}
 215		dprintk("%02x%02x%02x%02x ",
 216			buf[j], buf[j+1], buf[j+2], buf[j+3]);
 217	}
 218	dprintk("\n");
 219}
 220#else
 221static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 222{
 223	/* NOP */
 224}
 225#endif
 226
 227static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
 228{
 229	return (struct rpc_xprt *) sk->sk_user_data;
 230}
 231
 232static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
 233{
 234	return (struct sockaddr *) &xprt->addr;
 235}
 236
 237static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
 238{
 239	return (struct sockaddr_un *) &xprt->addr;
 240}
 241
 242static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
 243{
 244	return (struct sockaddr_in *) &xprt->addr;
 245}
 246
 247static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
 248{
 249	return (struct sockaddr_in6 *) &xprt->addr;
 250}
 251
 252static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
 253{
 254	struct sockaddr *sap = xs_addr(xprt);
 255	struct sockaddr_in6 *sin6;
 256	struct sockaddr_in *sin;
 257	struct sockaddr_un *sun;
 258	char buf[128];
 259
 260	switch (sap->sa_family) {
 261	case AF_LOCAL:
 262		sun = xs_addr_un(xprt);
 263		strlcpy(buf, sun->sun_path, sizeof(buf));
 264		xprt->address_strings[RPC_DISPLAY_ADDR] =
 265						kstrdup(buf, GFP_KERNEL);
 266		break;
 267	case AF_INET:
 268		(void)rpc_ntop(sap, buf, sizeof(buf));
 269		xprt->address_strings[RPC_DISPLAY_ADDR] =
 270						kstrdup(buf, GFP_KERNEL);
 271		sin = xs_addr_in(xprt);
 272		snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
 273		break;
 274	case AF_INET6:
 275		(void)rpc_ntop(sap, buf, sizeof(buf));
 276		xprt->address_strings[RPC_DISPLAY_ADDR] =
 277						kstrdup(buf, GFP_KERNEL);
 278		sin6 = xs_addr_in6(xprt);
 279		snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
 280		break;
 281	default:
 282		BUG();
 283	}
 284
 285	xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
 286}
 287
 288static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
 289{
 290	struct sockaddr *sap = xs_addr(xprt);
 291	char buf[128];
 292
 293	snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
 294	xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
 295
 296	snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
 297	xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
 298}
 299
 300static void xs_format_peer_addresses(struct rpc_xprt *xprt,
 301				     const char *protocol,
 302				     const char *netid)
 303{
 304	xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
 305	xprt->address_strings[RPC_DISPLAY_NETID] = netid;
 306	xs_format_common_peer_addresses(xprt);
 307	xs_format_common_peer_ports(xprt);
 308}
 309
 310static void xs_update_peer_port(struct rpc_xprt *xprt)
 311{
 312	kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
 313	kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
 314
 315	xs_format_common_peer_ports(xprt);
 316}
 317
 318static void xs_free_peer_addresses(struct rpc_xprt *xprt)
 319{
 320	unsigned int i;
 321
 322	for (i = 0; i < RPC_DISPLAY_MAX; i++)
 323		switch (i) {
 324		case RPC_DISPLAY_PROTO:
 325		case RPC_DISPLAY_NETID:
 326			continue;
 327		default:
 328			kfree(xprt->address_strings[i]);
 329		}
 330}
 331
 332static size_t
 333xs_alloc_sparse_pages(struct xdr_buf *buf, size_t want, gfp_t gfp)
 334{
 335	size_t i,n;
 336
 337	if (!want || !(buf->flags & XDRBUF_SPARSE_PAGES))
 338		return want;
 339	n = (buf->page_base + want + PAGE_SIZE - 1) >> PAGE_SHIFT;
 340	for (i = 0; i < n; i++) {
 341		if (buf->pages[i])
 342			continue;
 343		buf->bvec[i].bv_page = buf->pages[i] = alloc_page(gfp);
 344		if (!buf->pages[i]) {
 345			i *= PAGE_SIZE;
 346			return i > buf->page_base ? i - buf->page_base : 0;
 347		}
 348	}
 349	return want;
 350}
 351
 352static ssize_t
 353xs_sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags, size_t seek)
 354{
 355	ssize_t ret;
 356	if (seek != 0)
 357		iov_iter_advance(&msg->msg_iter, seek);
 358	ret = sock_recvmsg(sock, msg, flags);
 359	return ret > 0 ? ret + seek : ret;
 360}
 361
 362static ssize_t
 363xs_read_kvec(struct socket *sock, struct msghdr *msg, int flags,
 364		struct kvec *kvec, size_t count, size_t seek)
 365{
 366	iov_iter_kvec(&msg->msg_iter, READ, kvec, 1, count);
 367	return xs_sock_recvmsg(sock, msg, flags, seek);
 368}
 369
 370static ssize_t
 371xs_read_bvec(struct socket *sock, struct msghdr *msg, int flags,
 372		struct bio_vec *bvec, unsigned long nr, size_t count,
 373		size_t seek)
 374{
 375	iov_iter_bvec(&msg->msg_iter, READ, bvec, nr, count);
 376	return xs_sock_recvmsg(sock, msg, flags, seek);
 377}
 378
 379static ssize_t
 380xs_read_discard(struct socket *sock, struct msghdr *msg, int flags,
 381		size_t count)
 382{
 383	iov_iter_discard(&msg->msg_iter, READ, count);
 384	return sock_recvmsg(sock, msg, flags);
 385}
 386
 387#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
 388static void
 389xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
 390{
 391	struct bvec_iter bi = {
 392		.bi_size = count,
 393	};
 394	struct bio_vec bv;
 395
 396	bvec_iter_advance(bvec, &bi, seek & PAGE_MASK);
 397	for_each_bvec(bv, bvec, bi, bi)
 398		flush_dcache_page(bv.bv_page);
 399}
 400#else
 401static inline void
 402xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
 403{
 404}
 405#endif
 406
 407static ssize_t
 408xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags,
 409		struct xdr_buf *buf, size_t count, size_t seek, size_t *read)
 410{
 411	size_t want, seek_init = seek, offset = 0;
 412	ssize_t ret;
 413
 414	want = min_t(size_t, count, buf->head[0].iov_len);
 415	if (seek < want) {
 416		ret = xs_read_kvec(sock, msg, flags, &buf->head[0], want, seek);
 417		if (ret <= 0)
 418			goto sock_err;
 419		offset += ret;
 420		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 421			goto out;
 422		if (ret != want)
 423			goto out;
 424		seek = 0;
 425	} else {
 426		seek -= want;
 427		offset += want;
 428	}
 429
 430	want = xs_alloc_sparse_pages(buf,
 431			min_t(size_t, count - offset, buf->page_len),
 432			GFP_KERNEL);
 433	if (seek < want) {
 434		ret = xs_read_bvec(sock, msg, flags, buf->bvec,
 435				xdr_buf_pagecount(buf),
 436				want + buf->page_base,
 437				seek + buf->page_base);
 438		if (ret <= 0)
 439			goto sock_err;
 440		xs_flush_bvec(buf->bvec, ret, seek + buf->page_base);
 441		ret -= buf->page_base;
 442		offset += ret;
 443		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 444			goto out;
 445		if (ret != want)
 446			goto out;
 447		seek = 0;
 448	} else {
 449		seek -= want;
 450		offset += want;
 451	}
 452
 453	want = min_t(size_t, count - offset, buf->tail[0].iov_len);
 454	if (seek < want) {
 455		ret = xs_read_kvec(sock, msg, flags, &buf->tail[0], want, seek);
 456		if (ret <= 0)
 457			goto sock_err;
 458		offset += ret;
 459		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 460			goto out;
 461		if (ret != want)
 462			goto out;
 463	} else if (offset < seek_init)
 464		offset = seek_init;
 465	ret = -EMSGSIZE;
 466out:
 467	*read = offset - seek_init;
 468	return ret;
 469sock_err:
 470	offset += seek;
 471	goto out;
 472}
 473
 474static void
 475xs_read_header(struct sock_xprt *transport, struct xdr_buf *buf)
 476{
 477	if (!transport->recv.copied) {
 478		if (buf->head[0].iov_len >= transport->recv.offset)
 479			memcpy(buf->head[0].iov_base,
 480					&transport->recv.xid,
 481					transport->recv.offset);
 482		transport->recv.copied = transport->recv.offset;
 483	}
 484}
 485
 486static bool
 487xs_read_stream_request_done(struct sock_xprt *transport)
 488{
 489	return transport->recv.fraghdr & cpu_to_be32(RPC_LAST_STREAM_FRAGMENT);
 490}
 491
 492static void
 493xs_read_stream_check_eor(struct sock_xprt *transport,
 494		struct msghdr *msg)
 495{
 496	if (xs_read_stream_request_done(transport))
 497		msg->msg_flags |= MSG_EOR;
 498}
 499
 500static ssize_t
 501xs_read_stream_request(struct sock_xprt *transport, struct msghdr *msg,
 502		int flags, struct rpc_rqst *req)
 503{
 504	struct xdr_buf *buf = &req->rq_private_buf;
 505	size_t want, read;
 506	ssize_t ret;
 507
 508	xs_read_header(transport, buf);
 509
 510	want = transport->recv.len - transport->recv.offset;
 511	if (want != 0) {
 512		ret = xs_read_xdr_buf(transport->sock, msg, flags, buf,
 513				transport->recv.copied + want,
 514				transport->recv.copied,
 515				&read);
 516		transport->recv.offset += read;
 517		transport->recv.copied += read;
 518	}
 519
 520	if (transport->recv.offset == transport->recv.len)
 521		xs_read_stream_check_eor(transport, msg);
 522
 523	if (want == 0)
 524		return 0;
 525
 526	switch (ret) {
 527	default:
 528		break;
 529	case -EFAULT:
 530	case -EMSGSIZE:
 531		msg->msg_flags |= MSG_TRUNC;
 532		return read;
 533	case 0:
 534		return -ESHUTDOWN;
 535	}
 536	return ret < 0 ? ret : read;
 537}
 538
 539static size_t
 540xs_read_stream_headersize(bool isfrag)
 541{
 542	if (isfrag)
 543		return sizeof(__be32);
 544	return 3 * sizeof(__be32);
 545}
 546
 547static ssize_t
 548xs_read_stream_header(struct sock_xprt *transport, struct msghdr *msg,
 549		int flags, size_t want, size_t seek)
 550{
 551	struct kvec kvec = {
 552		.iov_base = &transport->recv.fraghdr,
 553		.iov_len = want,
 554	};
 555	return xs_read_kvec(transport->sock, msg, flags, &kvec, want, seek);
 556}
 557
 558#if defined(CONFIG_SUNRPC_BACKCHANNEL)
 559static ssize_t
 560xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 561{
 562	struct rpc_xprt *xprt = &transport->xprt;
 563	struct rpc_rqst *req;
 564	ssize_t ret;
 565
 566	/* Is this transport associated with the backchannel? */
 567	if (!xprt->bc_serv)
 568		return -ESHUTDOWN;
 569
 570	/* Look up and lock the request corresponding to the given XID */
 571	req = xprt_lookup_bc_request(xprt, transport->recv.xid);
 572	if (!req) {
 573		printk(KERN_WARNING "Callback slot table overflowed\n");
 574		return -ESHUTDOWN;
 575	}
 576	if (transport->recv.copied && !req->rq_private_buf.len)
 577		return -ESHUTDOWN;
 578
 579	ret = xs_read_stream_request(transport, msg, flags, req);
 580	if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 581		xprt_complete_bc_request(req, transport->recv.copied);
 582	else
 583		req->rq_private_buf.len = transport->recv.copied;
 584
 585	return ret;
 586}
 587#else /* CONFIG_SUNRPC_BACKCHANNEL */
 588static ssize_t
 589xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 590{
 591	return -ESHUTDOWN;
 592}
 593#endif /* CONFIG_SUNRPC_BACKCHANNEL */
 594
 595static ssize_t
 596xs_read_stream_reply(struct sock_xprt *transport, struct msghdr *msg, int flags)
 597{
 598	struct rpc_xprt *xprt = &transport->xprt;
 599	struct rpc_rqst *req;
 600	ssize_t ret = 0;
 601
 602	/* Look up and lock the request corresponding to the given XID */
 603	spin_lock(&xprt->queue_lock);
 604	req = xprt_lookup_rqst(xprt, transport->recv.xid);
 605	if (!req || (transport->recv.copied && !req->rq_private_buf.len)) {
 606		msg->msg_flags |= MSG_TRUNC;
 607		goto out;
 608	}
 609	xprt_pin_rqst(req);
 610	spin_unlock(&xprt->queue_lock);
 611
 612	ret = xs_read_stream_request(transport, msg, flags, req);
 613
 614	spin_lock(&xprt->queue_lock);
 615	if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 616		xprt_complete_rqst(req->rq_task, transport->recv.copied);
 617	else
 618		req->rq_private_buf.len = transport->recv.copied;
 619	xprt_unpin_rqst(req);
 620out:
 621	spin_unlock(&xprt->queue_lock);
 622	return ret;
 623}
 624
 625static ssize_t
 626xs_read_stream(struct sock_xprt *transport, int flags)
 627{
 628	struct msghdr msg = { 0 };
 629	size_t want, read = 0;
 630	ssize_t ret = 0;
 631
 632	if (transport->recv.len == 0) {
 633		want = xs_read_stream_headersize(transport->recv.copied != 0);
 634		ret = xs_read_stream_header(transport, &msg, flags, want,
 635				transport->recv.offset);
 636		if (ret <= 0)
 637			goto out_err;
 638		transport->recv.offset = ret;
 639		if (transport->recv.offset != want)
 640			return transport->recv.offset;
 641		transport->recv.len = be32_to_cpu(transport->recv.fraghdr) &
 642			RPC_FRAGMENT_SIZE_MASK;
 643		transport->recv.offset -= sizeof(transport->recv.fraghdr);
 644		read = ret;
 645	}
 646
 647	switch (be32_to_cpu(transport->recv.calldir)) {
 648	default:
 649		msg.msg_flags |= MSG_TRUNC;
 650		break;
 651	case RPC_CALL:
 652		ret = xs_read_stream_call(transport, &msg, flags);
 653		break;
 654	case RPC_REPLY:
 655		ret = xs_read_stream_reply(transport, &msg, flags);
 656	}
 657	if (msg.msg_flags & MSG_TRUNC) {
 658		transport->recv.calldir = cpu_to_be32(-1);
 659		transport->recv.copied = -1;
 660	}
 661	if (ret < 0)
 662		goto out_err;
 663	read += ret;
 664	if (transport->recv.offset < transport->recv.len) {
 665		if (!(msg.msg_flags & MSG_TRUNC))
 666			return read;
 667		msg.msg_flags = 0;
 668		ret = xs_read_discard(transport->sock, &msg, flags,
 669				transport->recv.len - transport->recv.offset);
 670		if (ret <= 0)
 671			goto out_err;
 672		transport->recv.offset += ret;
 673		read += ret;
 674		if (transport->recv.offset != transport->recv.len)
 675			return read;
 676	}
 677	if (xs_read_stream_request_done(transport)) {
 678		trace_xs_stream_read_request(transport);
 679		transport->recv.copied = 0;
 680	}
 681	transport->recv.offset = 0;
 682	transport->recv.len = 0;
 683	return read;
 684out_err:
 685	return ret != 0 ? ret : -ESHUTDOWN;
 686}
 687
 688static __poll_t xs_poll_socket(struct sock_xprt *transport)
 689{
 690	return transport->sock->ops->poll(transport->file, transport->sock,
 691			NULL);
 692}
 693
 694static bool xs_poll_socket_readable(struct sock_xprt *transport)
 695{
 696	__poll_t events = xs_poll_socket(transport);
 697
 698	return (events & (EPOLLIN | EPOLLRDNORM)) && !(events & EPOLLRDHUP);
 699}
 700
 701static void xs_poll_check_readable(struct sock_xprt *transport)
 702{
 703
 704	clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
 705	if (!xs_poll_socket_readable(transport))
 706		return;
 707	if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
 708		queue_work(xprtiod_workqueue, &transport->recv_worker);
 709}
 710
 711static void xs_stream_data_receive(struct sock_xprt *transport)
 712{
 713	size_t read = 0;
 714	ssize_t ret = 0;
 715
 716	mutex_lock(&transport->recv_mutex);
 717	if (transport->sock == NULL)
 718		goto out;
 719	for (;;) {
 720		ret = xs_read_stream(transport, MSG_DONTWAIT);
 721		if (ret < 0)
 722			break;
 723		read += ret;
 724		cond_resched();
 725	}
 726	if (ret == -ESHUTDOWN)
 727		kernel_sock_shutdown(transport->sock, SHUT_RDWR);
 728	else
 729		xs_poll_check_readable(transport);
 730out:
 731	mutex_unlock(&transport->recv_mutex);
 732	trace_xs_stream_read_data(&transport->xprt, ret, read);
 733}
 734
 735static void xs_stream_data_receive_workfn(struct work_struct *work)
 736{
 737	struct sock_xprt *transport =
 738		container_of(work, struct sock_xprt, recv_worker);
 739	unsigned int pflags = memalloc_nofs_save();
 740
 741	xs_stream_data_receive(transport);
 742	memalloc_nofs_restore(pflags);
 743}
 744
 745static void
 746xs_stream_reset_connect(struct sock_xprt *transport)
 747{
 748	transport->recv.offset = 0;
 749	transport->recv.len = 0;
 750	transport->recv.copied = 0;
 751	transport->xmit.offset = 0;
 752}
 753
 754static void
 755xs_stream_start_connect(struct sock_xprt *transport)
 756{
 757	transport->xprt.stat.connect_count++;
 758	transport->xprt.stat.connect_start = jiffies;
 759}
 760
 761#define XS_SENDMSG_FLAGS	(MSG_DONTWAIT | MSG_NOSIGNAL)
 762
 763/**
 764 * xs_nospace - handle transmit was incomplete
 765 * @req: pointer to RPC request
 
 766 *
 767 */
 768static int xs_nospace(struct rpc_rqst *req)
 769{
 770	struct rpc_xprt *xprt = req->rq_xprt;
 771	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 772	struct sock *sk = transport->inet;
 773	int ret = -EAGAIN;
 774
 775	trace_rpc_socket_nospace(req, transport);
 776
 777	/* Protect against races with write_space */
 778	spin_lock(&xprt->transport_lock);
 779
 780	/* Don't race with disconnect */
 781	if (xprt_connected(xprt)) {
 782		/* wait for more buffer space */
 
 
 783		sk->sk_write_pending++;
 784		xprt_wait_for_buffer_space(xprt);
 785	} else
 786		ret = -ENOTCONN;
 787
 788	spin_unlock(&xprt->transport_lock);
 
 
 789
 790	/* Race breaker in case memory is freed before above code is called */
 791	if (ret == -EAGAIN) {
 792		struct socket_wq *wq;
 793
 794		rcu_read_lock();
 795		wq = rcu_dereference(sk->sk_wq);
 796		set_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags);
 797		rcu_read_unlock();
 798
 799		sk->sk_write_space(sk);
 800	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 801	return ret;
 802}
 803
 804static void
 805xs_stream_prepare_request(struct rpc_rqst *req)
 806{
 807	xdr_free_bvec(&req->rq_rcv_buf);
 808	req->rq_task->tk_status = xdr_alloc_bvec(&req->rq_rcv_buf, GFP_KERNEL);
 809}
 810
 811/*
 812 * Determine if the previous message in the stream was aborted before it
 813 * could complete transmission.
 814 */
 815static bool
 816xs_send_request_was_aborted(struct sock_xprt *transport, struct rpc_rqst *req)
 817{
 818	return transport->xmit.offset != 0 && req->rq_bytes_sent == 0;
 819}
 820
 821/*
 822 * Return the stream record marker field for a record of length < 2^31-1
 823 */
 824static rpc_fraghdr
 825xs_stream_record_marker(struct xdr_buf *xdr)
 826{
 827	if (!xdr->len)
 828		return 0;
 829	return cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | (u32)xdr->len);
 830}
 831
 832/**
 833 * xs_local_send_request - write an RPC request to an AF_LOCAL socket
 834 * @req: pointer to RPC request
 835 *
 836 * Return values:
 837 *        0:	The request has been sent
 838 *   EAGAIN:	The socket was blocked, please call again later to
 839 *		complete the request
 840 * ENOTCONN:	Caller needs to invoke connect logic then call again
 841 *    other:	Some other error occurred, the request was not sent
 842 */
 843static int xs_local_send_request(struct rpc_rqst *req)
 844{
 845	struct rpc_xprt *xprt = req->rq_xprt;
 846	struct sock_xprt *transport =
 847				container_of(xprt, struct sock_xprt, xprt);
 848	struct xdr_buf *xdr = &req->rq_snd_buf;
 849	rpc_fraghdr rm = xs_stream_record_marker(xdr);
 850	unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
 851	struct msghdr msg = {
 852		.msg_flags	= XS_SENDMSG_FLAGS,
 853	};
 
 854	unsigned int sent;
 855	int status;
 856
 857	/* Close the stream if the previous transmission was incomplete */
 858	if (xs_send_request_was_aborted(transport, req)) {
 859		xs_close(xprt);
 860		return -ENOTCONN;
 861	}
 862
 863	xs_pktdump("packet data:",
 864			req->rq_svec->iov_base, req->rq_svec->iov_len);
 865
 
 
 866	req->rq_xtime = ktime_get();
 867	status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
 868				   transport->xmit.offset, rm, &sent);
 869	dprintk("RPC:       %s(%u) = %d\n",
 870			__func__, xdr->len - transport->xmit.offset, status);
 871
 872	if (status == -EAGAIN && sock_writeable(transport->inet))
 873		status = -ENOBUFS;
 874
 875	if (likely(sent > 0) || status == 0) {
 876		transport->xmit.offset += sent;
 877		req->rq_bytes_sent = transport->xmit.offset;
 878		if (likely(req->rq_bytes_sent >= msglen)) {
 879			req->rq_xmit_bytes_sent += transport->xmit.offset;
 880			transport->xmit.offset = 0;
 881			return 0;
 882		}
 883		status = -EAGAIN;
 
 884	}
 885
 886	switch (status) {
 887	case -ENOBUFS:
 888		break;
 889	case -EAGAIN:
 890		status = xs_nospace(req);
 891		break;
 892	default:
 893		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 894			-status);
 895		fallthrough;
 896	case -EPIPE:
 897		xs_close(xprt);
 898		status = -ENOTCONN;
 899	}
 900
 901	return status;
 902}
 903
 904/**
 905 * xs_udp_send_request - write an RPC request to a UDP socket
 906 * @req: pointer to RPC request
 907 *
 908 * Return values:
 909 *        0:	The request has been sent
 910 *   EAGAIN:	The socket was blocked, please call again later to
 911 *		complete the request
 912 * ENOTCONN:	Caller needs to invoke connect logic then call again
 913 *    other:	Some other error occurred, the request was not sent
 914 */
 915static int xs_udp_send_request(struct rpc_rqst *req)
 916{
 917	struct rpc_xprt *xprt = req->rq_xprt;
 918	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 919	struct xdr_buf *xdr = &req->rq_snd_buf;
 920	struct msghdr msg = {
 921		.msg_name	= xs_addr(xprt),
 922		.msg_namelen	= xprt->addrlen,
 923		.msg_flags	= XS_SENDMSG_FLAGS,
 924	};
 925	unsigned int sent;
 926	int status;
 927
 928	xs_pktdump("packet data:",
 929				req->rq_svec->iov_base,
 930				req->rq_svec->iov_len);
 931
 932	if (!xprt_bound(xprt))
 933		return -ENOTCONN;
 934
 935	if (!xprt_request_get_cong(xprt, req))
 936		return -EBADSLT;
 937
 
 
 
 938	req->rq_xtime = ktime_get();
 939	status = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, 0, &sent);
 940
 941	dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
 942			xdr->len, status);
 943
 944	/* firewall is blocking us, don't return -EAGAIN or we end up looping */
 945	if (status == -EPERM)
 946		goto process_status;
 947
 948	if (status == -EAGAIN && sock_writeable(transport->inet))
 949		status = -ENOBUFS;
 950
 951	if (sent > 0 || status == 0) {
 952		req->rq_xmit_bytes_sent += sent;
 953		if (sent >= req->rq_slen)
 954			return 0;
 955		/* Still some bytes left; set up for a retry later. */
 956		status = -EAGAIN;
 957	}
 958
 959process_status:
 960	switch (status) {
 961	case -ENOTSOCK:
 962		status = -ENOTCONN;
 963		/* Should we call xs_close() here? */
 964		break;
 965	case -EAGAIN:
 966		status = xs_nospace(req);
 967		break;
 968	case -ENETUNREACH:
 969	case -ENOBUFS:
 970	case -EPIPE:
 971	case -ECONNREFUSED:
 972	case -EPERM:
 973		/* When the server has died, an ICMP port unreachable message
 974		 * prompts ECONNREFUSED. */
 975		break;
 976	default:
 977		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 978			-status);
 979	}
 980
 981	return status;
 982}
 983
 984/**
 985 * xs_tcp_send_request - write an RPC request to a TCP socket
 986 * @req: pointer to RPC request
 987 *
 988 * Return values:
 989 *        0:	The request has been sent
 990 *   EAGAIN:	The socket was blocked, please call again later to
 991 *		complete the request
 992 * ENOTCONN:	Caller needs to invoke connect logic then call again
 993 *    other:	Some other error occurred, the request was not sent
 994 *
 995 * XXX: In the case of soft timeouts, should we eventually give up
 996 *	if sendmsg is not able to make progress?
 997 */
 998static int xs_tcp_send_request(struct rpc_rqst *req)
 999{
1000	struct rpc_xprt *xprt = req->rq_xprt;
1001	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1002	struct xdr_buf *xdr = &req->rq_snd_buf;
1003	rpc_fraghdr rm = xs_stream_record_marker(xdr);
1004	unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
1005	struct msghdr msg = {
1006		.msg_flags	= XS_SENDMSG_FLAGS,
1007	};
1008	bool vm_wait = false;
1009	unsigned int sent;
1010	int status;
1011
1012	/* Close the stream if the previous transmission was incomplete */
1013	if (xs_send_request_was_aborted(transport, req)) {
1014		if (transport->sock != NULL)
1015			kernel_sock_shutdown(transport->sock, SHUT_RDWR);
1016		return -ENOTCONN;
1017	}
1018	if (!transport->inet)
1019		return -ENOTCONN;
1020
1021	xs_pktdump("packet data:",
1022				req->rq_svec->iov_base,
1023				req->rq_svec->iov_len);
1024
1025	if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state))
1026		xs_tcp_set_socket_timeouts(xprt, transport->sock);
1027
 
 
1028	/* Continue transmitting the packet/record. We must be careful
1029	 * to cope with writespace callbacks arriving _after_ we have
1030	 * called sendmsg(). */
1031	req->rq_xtime = ktime_get();
1032	tcp_sock_set_cork(transport->inet, true);
1033	while (1) {
 
 
 
1034		status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
1035					   transport->xmit.offset, rm, &sent);
1036
1037		dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
1038				xdr->len - transport->xmit.offset, status);
1039
1040		/* If we've sent the entire packet, immediately
1041		 * reset the count of bytes sent. */
1042		transport->xmit.offset += sent;
1043		req->rq_bytes_sent = transport->xmit.offset;
1044		if (likely(req->rq_bytes_sent >= msglen)) {
1045			req->rq_xmit_bytes_sent += transport->xmit.offset;
1046			transport->xmit.offset = 0;
1047			if (atomic_long_read(&xprt->xmit_queuelen) == 1)
1048				tcp_sock_set_cork(transport->inet, false);
1049			return 0;
1050		}
1051
1052		WARN_ON_ONCE(sent == 0 && status == 0);
1053
1054		if (status == -EAGAIN ) {
1055			/*
1056			 * Return EAGAIN if we're sure we're hitting the
1057			 * socket send buffer limits.
1058			 */
1059			if (test_bit(SOCK_NOSPACE, &transport->sock->flags))
1060				break;
1061			/*
1062			 * Did we hit a memory allocation failure?
1063			 */
1064			if (sent == 0) {
1065				status = -ENOBUFS;
1066				if (vm_wait)
1067					break;
1068				/* Retry, knowing now that we're below the
1069				 * socket send buffer limit
1070				 */
1071				vm_wait = true;
1072			}
1073			continue;
1074		}
1075		if (status < 0)
1076			break;
1077		vm_wait = false;
1078	}
1079
1080	switch (status) {
1081	case -ENOTSOCK:
1082		status = -ENOTCONN;
1083		/* Should we call xs_close() here? */
1084		break;
1085	case -EAGAIN:
1086		status = xs_nospace(req);
1087		break;
1088	case -ECONNRESET:
1089	case -ECONNREFUSED:
1090	case -ENOTCONN:
1091	case -EADDRINUSE:
1092	case -ENOBUFS:
1093	case -EPIPE:
1094		break;
1095	default:
1096		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1097			-status);
1098	}
1099
1100	return status;
1101}
1102
1103static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1104{
1105	transport->old_data_ready = sk->sk_data_ready;
1106	transport->old_state_change = sk->sk_state_change;
1107	transport->old_write_space = sk->sk_write_space;
1108	transport->old_error_report = sk->sk_error_report;
1109}
1110
1111static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1112{
1113	sk->sk_data_ready = transport->old_data_ready;
1114	sk->sk_state_change = transport->old_state_change;
1115	sk->sk_write_space = transport->old_write_space;
1116	sk->sk_error_report = transport->old_error_report;
1117}
1118
1119static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
1120{
1121	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1122
1123	clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1124	clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state);
1125	clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state);
1126	clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state);
 
1127}
1128
1129static void xs_run_error_worker(struct sock_xprt *transport, unsigned int nr)
1130{
1131	set_bit(nr, &transport->sock_state);
1132	queue_work(xprtiod_workqueue, &transport->error_worker);
1133}
1134
1135static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
1136{
 
1137	smp_mb__before_atomic();
1138	clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1139	clear_bit(XPRT_CLOSING, &xprt->state);
1140	xs_sock_reset_state_flags(xprt);
1141	smp_mb__after_atomic();
1142}
1143
1144/**
1145 * xs_error_report - callback to handle TCP socket state errors
1146 * @sk: socket
1147 *
1148 * Note: we don't call sock_error() since there may be a rpc_task
1149 * using the socket, and so we don't want to clear sk->sk_err.
1150 */
1151static void xs_error_report(struct sock *sk)
1152{
1153	struct sock_xprt *transport;
1154	struct rpc_xprt *xprt;
1155
1156	read_lock_bh(&sk->sk_callback_lock);
1157	if (!(xprt = xprt_from_sock(sk)))
1158		goto out;
1159
1160	transport = container_of(xprt, struct sock_xprt, xprt);
1161	transport->xprt_err = -sk->sk_err;
1162	if (transport->xprt_err == 0)
1163		goto out;
1164	dprintk("RPC:       xs_error_report client %p, error=%d...\n",
1165			xprt, -transport->xprt_err);
1166	trace_rpc_socket_error(xprt, sk->sk_socket, transport->xprt_err);
1167
1168	/* barrier ensures xprt_err is set before XPRT_SOCK_WAKE_ERROR */
1169	smp_mb__before_atomic();
1170	xs_run_error_worker(transport, XPRT_SOCK_WAKE_ERROR);
1171 out:
1172	read_unlock_bh(&sk->sk_callback_lock);
1173}
1174
1175static void xs_reset_transport(struct sock_xprt *transport)
1176{
1177	struct socket *sock = transport->sock;
1178	struct sock *sk = transport->inet;
1179	struct rpc_xprt *xprt = &transport->xprt;
1180	struct file *filp = transport->file;
1181
1182	if (sk == NULL)
1183		return;
 
 
 
 
 
 
 
 
 
 
1184
1185	if (atomic_read(&transport->xprt.swapper))
1186		sk_clear_memalloc(sk);
1187
1188	kernel_sock_shutdown(sock, SHUT_RDWR);
1189
1190	mutex_lock(&transport->recv_mutex);
1191	write_lock_bh(&sk->sk_callback_lock);
1192	transport->inet = NULL;
1193	transport->sock = NULL;
1194	transport->file = NULL;
1195
1196	sk->sk_user_data = NULL;
1197
1198	xs_restore_old_callbacks(transport, sk);
1199	xprt_clear_connected(xprt);
1200	write_unlock_bh(&sk->sk_callback_lock);
1201	xs_sock_reset_connection_flags(xprt);
1202	/* Reset stream record info */
1203	xs_stream_reset_connect(transport);
 
1204	mutex_unlock(&transport->recv_mutex);
1205
1206	trace_rpc_socket_close(xprt, sock);
1207	fput(filp);
1208
1209	xprt_disconnect_done(xprt);
1210}
1211
1212/**
1213 * xs_close - close a socket
1214 * @xprt: transport
1215 *
1216 * This is used when all requests are complete; ie, no DRC state remains
1217 * on the server we want to save.
1218 *
1219 * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
1220 * xs_reset_transport() zeroing the socket from underneath a writer.
1221 */
1222static void xs_close(struct rpc_xprt *xprt)
1223{
1224	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1225
1226	dprintk("RPC:       xs_close xprt %p\n", xprt);
1227
1228	xs_reset_transport(transport);
1229	xprt->reestablish_timeout = 0;
1230}
1231
1232static void xs_inject_disconnect(struct rpc_xprt *xprt)
1233{
1234	dprintk("RPC:       injecting transport disconnect on xprt=%p\n",
1235		xprt);
1236	xprt_disconnect_done(xprt);
1237}
1238
1239static void xs_xprt_free(struct rpc_xprt *xprt)
1240{
1241	xs_free_peer_addresses(xprt);
1242	xprt_free(xprt);
1243}
1244
1245/**
1246 * xs_destroy - prepare to shutdown a transport
1247 * @xprt: doomed transport
1248 *
1249 */
1250static void xs_destroy(struct rpc_xprt *xprt)
1251{
1252	struct sock_xprt *transport = container_of(xprt,
1253			struct sock_xprt, xprt);
1254	dprintk("RPC:       xs_destroy xprt %p\n", xprt);
1255
1256	cancel_delayed_work_sync(&transport->connect_worker);
1257	xs_close(xprt);
1258	cancel_work_sync(&transport->recv_worker);
1259	cancel_work_sync(&transport->error_worker);
1260	xs_xprt_free(xprt);
1261	module_put(THIS_MODULE);
1262}
1263
1264/**
1265 * xs_udp_data_read_skb - receive callback for UDP sockets
1266 * @xprt: transport
1267 * @sk: socket
1268 * @skb: skbuff
1269 *
1270 */
1271static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
1272		struct sock *sk,
1273		struct sk_buff *skb)
1274{
1275	struct rpc_task *task;
1276	struct rpc_rqst *rovr;
1277	int repsize, copied;
1278	u32 _xid;
1279	__be32 *xp;
1280
1281	repsize = skb->len;
1282	if (repsize < 4) {
1283		dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
1284		return;
1285	}
1286
1287	/* Copy the XID from the skb... */
1288	xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
1289	if (xp == NULL)
1290		return;
1291
1292	/* Look up and lock the request corresponding to the given XID */
1293	spin_lock(&xprt->queue_lock);
1294	rovr = xprt_lookup_rqst(xprt, *xp);
1295	if (!rovr)
1296		goto out_unlock;
1297	xprt_pin_rqst(rovr);
1298	xprt_update_rtt(rovr->rq_task);
1299	spin_unlock(&xprt->queue_lock);
1300	task = rovr->rq_task;
1301
1302	if ((copied = rovr->rq_private_buf.buflen) > repsize)
1303		copied = repsize;
1304
1305	/* Suck it into the iovec, verify checksum if not done by hw. */
1306	if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1307		spin_lock(&xprt->queue_lock);
1308		__UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
1309		goto out_unpin;
1310	}
1311
1312
1313	spin_lock(&xprt->transport_lock);
1314	xprt_adjust_cwnd(xprt, task, copied);
1315	spin_unlock(&xprt->transport_lock);
1316	spin_lock(&xprt->queue_lock);
1317	xprt_complete_rqst(task, copied);
1318	__UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
1319out_unpin:
1320	xprt_unpin_rqst(rovr);
1321 out_unlock:
1322	spin_unlock(&xprt->queue_lock);
1323}
1324
1325static void xs_udp_data_receive(struct sock_xprt *transport)
1326{
1327	struct sk_buff *skb;
1328	struct sock *sk;
1329	int err;
1330
1331	mutex_lock(&transport->recv_mutex);
1332	sk = transport->inet;
1333	if (sk == NULL)
1334		goto out;
1335	for (;;) {
1336		skb = skb_recv_udp(sk, 0, 1, &err);
1337		if (skb == NULL)
1338			break;
1339		xs_udp_data_read_skb(&transport->xprt, sk, skb);
1340		consume_skb(skb);
1341		cond_resched();
1342	}
1343	xs_poll_check_readable(transport);
1344out:
1345	mutex_unlock(&transport->recv_mutex);
1346}
1347
1348static void xs_udp_data_receive_workfn(struct work_struct *work)
1349{
1350	struct sock_xprt *transport =
1351		container_of(work, struct sock_xprt, recv_worker);
1352	unsigned int pflags = memalloc_nofs_save();
1353
1354	xs_udp_data_receive(transport);
1355	memalloc_nofs_restore(pflags);
1356}
1357
1358/**
1359 * xs_data_ready - "data ready" callback for UDP sockets
1360 * @sk: socket with data to read
1361 *
1362 */
1363static void xs_data_ready(struct sock *sk)
1364{
1365	struct rpc_xprt *xprt;
1366
1367	read_lock_bh(&sk->sk_callback_lock);
1368	dprintk("RPC:       xs_data_ready...\n");
1369	xprt = xprt_from_sock(sk);
1370	if (xprt != NULL) {
1371		struct sock_xprt *transport = container_of(xprt,
1372				struct sock_xprt, xprt);
 
 
 
1373		transport->old_data_ready(sk);
1374		/* Any data means we had a useful conversation, so
1375		 * then we don't need to delay the next reconnect
1376		 */
1377		if (xprt->reestablish_timeout)
1378			xprt->reestablish_timeout = 0;
1379		if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1380			queue_work(xprtiod_workqueue, &transport->recv_worker);
1381	}
1382	read_unlock_bh(&sk->sk_callback_lock);
1383}
1384
1385/*
1386 * Helper function to force a TCP close if the server is sending
1387 * junk and/or it has put us in CLOSE_WAIT
1388 */
1389static void xs_tcp_force_close(struct rpc_xprt *xprt)
1390{
1391	xprt_force_disconnect(xprt);
1392}
1393
1394#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1395static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
1396{
1397	return PAGE_SIZE;
1398}
1399#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1400
1401/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1402 * xs_tcp_state_change - callback to handle TCP socket state changes
1403 * @sk: socket whose state has changed
1404 *
1405 */
1406static void xs_tcp_state_change(struct sock *sk)
1407{
1408	struct rpc_xprt *xprt;
1409	struct sock_xprt *transport;
1410
1411	read_lock_bh(&sk->sk_callback_lock);
1412	if (!(xprt = xprt_from_sock(sk)))
1413		goto out;
1414	dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1415	dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1416			sk->sk_state, xprt_connected(xprt),
1417			sock_flag(sk, SOCK_DEAD),
1418			sock_flag(sk, SOCK_ZAPPED),
1419			sk->sk_shutdown);
1420
1421	transport = container_of(xprt, struct sock_xprt, xprt);
1422	trace_rpc_socket_state_change(xprt, sk->sk_socket);
1423	switch (sk->sk_state) {
1424	case TCP_ESTABLISHED:
1425		if (!xprt_test_and_set_connected(xprt)) {
1426			xprt->connect_cookie++;
1427			clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
1428			xprt_clear_connecting(xprt);
1429
1430			xprt->stat.connect_count++;
1431			xprt->stat.connect_time += (long)jiffies -
1432						   xprt->stat.connect_start;
1433			xs_run_error_worker(transport, XPRT_SOCK_WAKE_PENDING);
1434		}
1435		break;
1436	case TCP_FIN_WAIT1:
1437		/* The client initiated a shutdown of the socket */
1438		xprt->connect_cookie++;
1439		xprt->reestablish_timeout = 0;
1440		set_bit(XPRT_CLOSING, &xprt->state);
1441		smp_mb__before_atomic();
1442		clear_bit(XPRT_CONNECTED, &xprt->state);
1443		clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1444		smp_mb__after_atomic();
1445		break;
1446	case TCP_CLOSE_WAIT:
1447		/* The server initiated a shutdown of the socket */
1448		xprt->connect_cookie++;
1449		clear_bit(XPRT_CONNECTED, &xprt->state);
1450		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1451		fallthrough;
1452	case TCP_CLOSING:
1453		/*
1454		 * If the server closed down the connection, make sure that
1455		 * we back off before reconnecting
1456		 */
1457		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1458			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1459		break;
1460	case TCP_LAST_ACK:
1461		set_bit(XPRT_CLOSING, &xprt->state);
1462		smp_mb__before_atomic();
1463		clear_bit(XPRT_CONNECTED, &xprt->state);
1464		smp_mb__after_atomic();
1465		break;
1466	case TCP_CLOSE:
1467		if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
1468					&transport->sock_state))
1469			xprt_clear_connecting(xprt);
1470		clear_bit(XPRT_CLOSING, &xprt->state);
1471		/* Trigger the socket release */
1472		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1473	}
1474 out:
1475	read_unlock_bh(&sk->sk_callback_lock);
1476}
1477
1478static void xs_write_space(struct sock *sk)
1479{
1480	struct socket_wq *wq;
1481	struct sock_xprt *transport;
1482	struct rpc_xprt *xprt;
1483
1484	if (!sk->sk_socket)
1485		return;
1486	clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1487
1488	if (unlikely(!(xprt = xprt_from_sock(sk))))
1489		return;
1490	transport = container_of(xprt, struct sock_xprt, xprt);
1491	rcu_read_lock();
1492	wq = rcu_dereference(sk->sk_wq);
1493	if (!wq || test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags) == 0)
1494		goto out;
1495
1496	xs_run_error_worker(transport, XPRT_SOCK_WAKE_WRITE);
1497	sk->sk_write_pending--;
1498out:
1499	rcu_read_unlock();
1500}
1501
1502/**
1503 * xs_udp_write_space - callback invoked when socket buffer space
1504 *                             becomes available
1505 * @sk: socket whose state has changed
1506 *
1507 * Called when more output buffer space is available for this socket.
1508 * We try not to wake our writers until they can make "significant"
1509 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1510 * with a bunch of small requests.
1511 */
1512static void xs_udp_write_space(struct sock *sk)
1513{
1514	read_lock_bh(&sk->sk_callback_lock);
1515
1516	/* from net/core/sock.c:sock_def_write_space */
1517	if (sock_writeable(sk))
1518		xs_write_space(sk);
1519
1520	read_unlock_bh(&sk->sk_callback_lock);
1521}
1522
1523/**
1524 * xs_tcp_write_space - callback invoked when socket buffer space
1525 *                             becomes available
1526 * @sk: socket whose state has changed
1527 *
1528 * Called when more output buffer space is available for this socket.
1529 * We try not to wake our writers until they can make "significant"
1530 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1531 * with a bunch of small requests.
1532 */
1533static void xs_tcp_write_space(struct sock *sk)
1534{
1535	read_lock_bh(&sk->sk_callback_lock);
1536
1537	/* from net/core/stream.c:sk_stream_write_space */
1538	if (sk_stream_is_writeable(sk))
1539		xs_write_space(sk);
1540
1541	read_unlock_bh(&sk->sk_callback_lock);
1542}
1543
1544static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1545{
1546	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1547	struct sock *sk = transport->inet;
1548
1549	if (transport->rcvsize) {
1550		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1551		sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1552	}
1553	if (transport->sndsize) {
1554		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1555		sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1556		sk->sk_write_space(sk);
1557	}
1558}
1559
1560/**
1561 * xs_udp_set_buffer_size - set send and receive limits
1562 * @xprt: generic transport
1563 * @sndsize: requested size of send buffer, in bytes
1564 * @rcvsize: requested size of receive buffer, in bytes
1565 *
1566 * Set socket send and receive buffer size limits.
1567 */
1568static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1569{
1570	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1571
1572	transport->sndsize = 0;
1573	if (sndsize)
1574		transport->sndsize = sndsize + 1024;
1575	transport->rcvsize = 0;
1576	if (rcvsize)
1577		transport->rcvsize = rcvsize + 1024;
1578
1579	xs_udp_do_set_buffer_size(xprt);
1580}
1581
1582/**
1583 * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1584 * @xprt: controlling transport
1585 * @task: task that timed out
1586 *
1587 * Adjust the congestion window after a retransmit timeout has occurred.
1588 */
1589static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1590{
1591	spin_lock(&xprt->transport_lock);
1592	xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1593	spin_unlock(&xprt->transport_lock);
1594}
1595
1596static int xs_get_random_port(void)
1597{
1598	unsigned short min = xprt_min_resvport, max = xprt_max_resvport;
1599	unsigned short range;
1600	unsigned short rand;
1601
1602	if (max < min)
1603		return -EADDRINUSE;
1604	range = max - min + 1;
1605	rand = (unsigned short) prandom_u32() % range;
1606	return rand + min;
1607}
1608
1609static unsigned short xs_sock_getport(struct socket *sock)
1610{
1611	struct sockaddr_storage buf;
1612	unsigned short port = 0;
1613
1614	if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0)
1615		goto out;
1616	switch (buf.ss_family) {
1617	case AF_INET6:
1618		port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1619		break;
1620	case AF_INET:
1621		port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1622	}
1623out:
1624	return port;
1625}
1626
1627/**
1628 * xs_set_port - reset the port number in the remote endpoint address
1629 * @xprt: generic transport
1630 * @port: new port number
1631 *
1632 */
1633static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1634{
1635	dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1636
1637	rpc_set_port(xs_addr(xprt), port);
1638	xs_update_peer_port(xprt);
1639}
1640
1641static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1642{
1643	if (transport->srcport == 0 && transport->xprt.reuseport)
1644		transport->srcport = xs_sock_getport(sock);
1645}
1646
1647static int xs_get_srcport(struct sock_xprt *transport)
1648{
1649	int port = transport->srcport;
1650
1651	if (port == 0 && transport->xprt.resvport)
1652		port = xs_get_random_port();
1653	return port;
1654}
1655
1656unsigned short get_srcport(struct rpc_xprt *xprt)
1657{
1658	struct sock_xprt *sock = container_of(xprt, struct sock_xprt, xprt);
1659	return xs_sock_getport(sock->sock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1660}
1661EXPORT_SYMBOL(get_srcport);
1662
1663static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1664{
1665	if (transport->srcport != 0)
1666		transport->srcport = 0;
1667	if (!transport->xprt.resvport)
1668		return 0;
1669	if (port <= xprt_min_resvport || port > xprt_max_resvport)
1670		return xprt_max_resvport;
1671	return --port;
1672}
1673static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1674{
1675	struct sockaddr_storage myaddr;
1676	int err, nloop = 0;
1677	int port = xs_get_srcport(transport);
1678	unsigned short last;
1679
1680	/*
1681	 * If we are asking for any ephemeral port (i.e. port == 0 &&
1682	 * transport->xprt.resvport == 0), don't bind.  Let the local
1683	 * port selection happen implicitly when the socket is used
1684	 * (for example at connect time).
1685	 *
1686	 * This ensures that we can continue to establish TCP
1687	 * connections even when all local ephemeral ports are already
1688	 * a part of some TCP connection.  This makes no difference
1689	 * for UDP sockets, but also doesn't harm them.
1690	 *
1691	 * If we're asking for any reserved port (i.e. port == 0 &&
1692	 * transport->xprt.resvport == 1) xs_get_srcport above will
1693	 * ensure that port is non-zero and we will bind as needed.
1694	 */
1695	if (port <= 0)
1696		return port;
1697
1698	memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1699	do {
1700		rpc_set_port((struct sockaddr *)&myaddr, port);
1701		err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1702				transport->xprt.addrlen);
1703		if (err == 0) {
1704			if (transport->xprt.reuseport)
1705				transport->srcport = port;
1706			break;
1707		}
1708		last = port;
1709		port = xs_next_srcport(transport, port);
1710		if (port > last)
1711			nloop++;
1712	} while (err == -EADDRINUSE && nloop != 2);
1713
1714	if (myaddr.ss_family == AF_INET)
1715		dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1716				&((struct sockaddr_in *)&myaddr)->sin_addr,
1717				port, err ? "failed" : "ok", err);
1718	else
1719		dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1720				&((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1721				port, err ? "failed" : "ok", err);
1722	return err;
1723}
1724
1725/*
1726 * We don't support autobind on AF_LOCAL sockets
1727 */
1728static void xs_local_rpcbind(struct rpc_task *task)
1729{
1730	xprt_set_bound(task->tk_xprt);
1731}
1732
1733static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1734{
1735}
1736
1737#ifdef CONFIG_DEBUG_LOCK_ALLOC
1738static struct lock_class_key xs_key[2];
1739static struct lock_class_key xs_slock_key[2];
1740
1741static inline void xs_reclassify_socketu(struct socket *sock)
1742{
1743	struct sock *sk = sock->sk;
1744
1745	sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1746		&xs_slock_key[1], "sk_lock-AF_LOCAL-RPC", &xs_key[1]);
1747}
1748
1749static inline void xs_reclassify_socket4(struct socket *sock)
1750{
1751	struct sock *sk = sock->sk;
1752
1753	sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1754		&xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1755}
1756
1757static inline void xs_reclassify_socket6(struct socket *sock)
1758{
1759	struct sock *sk = sock->sk;
1760
1761	sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1762		&xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1763}
1764
1765static inline void xs_reclassify_socket(int family, struct socket *sock)
1766{
1767	if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
1768		return;
1769
1770	switch (family) {
1771	case AF_LOCAL:
1772		xs_reclassify_socketu(sock);
1773		break;
1774	case AF_INET:
1775		xs_reclassify_socket4(sock);
1776		break;
1777	case AF_INET6:
1778		xs_reclassify_socket6(sock);
1779		break;
1780	}
1781}
1782#else
1783static inline void xs_reclassify_socket(int family, struct socket *sock)
1784{
1785}
1786#endif
1787
1788static void xs_dummy_setup_socket(struct work_struct *work)
1789{
1790}
1791
1792static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1793		struct sock_xprt *transport, int family, int type,
1794		int protocol, bool reuseport)
1795{
1796	struct file *filp;
1797	struct socket *sock;
1798	int err;
1799
1800	err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1801	if (err < 0) {
1802		dprintk("RPC:       can't create %d transport socket (%d).\n",
1803				protocol, -err);
1804		goto out;
1805	}
1806	xs_reclassify_socket(family, sock);
1807
1808	if (reuseport)
1809		sock_set_reuseport(sock->sk);
1810
1811	err = xs_bind(transport, sock);
1812	if (err) {
1813		sock_release(sock);
1814		goto out;
1815	}
1816
1817	filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1818	if (IS_ERR(filp))
1819		return ERR_CAST(filp);
1820	transport->file = filp;
1821
1822	return sock;
1823out:
1824	return ERR_PTR(err);
1825}
1826
1827static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1828				      struct socket *sock)
1829{
1830	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1831									xprt);
1832
1833	if (!transport->inet) {
1834		struct sock *sk = sock->sk;
1835
1836		write_lock_bh(&sk->sk_callback_lock);
1837
1838		xs_save_old_callbacks(transport, sk);
1839
1840		sk->sk_user_data = xprt;
1841		sk->sk_data_ready = xs_data_ready;
1842		sk->sk_write_space = xs_udp_write_space;
1843		sock_set_flag(sk, SOCK_FASYNC);
1844		sk->sk_error_report = xs_error_report;
 
1845
1846		xprt_clear_connected(xprt);
1847
1848		/* Reset to new socket */
1849		transport->sock = sock;
1850		transport->inet = sk;
1851
1852		write_unlock_bh(&sk->sk_callback_lock);
1853	}
1854
1855	xs_stream_start_connect(transport);
1856
1857	return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1858}
1859
1860/**
1861 * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1862 * @transport: socket transport to connect
1863 */
1864static int xs_local_setup_socket(struct sock_xprt *transport)
1865{
1866	struct rpc_xprt *xprt = &transport->xprt;
1867	struct file *filp;
1868	struct socket *sock;
1869	int status;
1870
1871	status = __sock_create(xprt->xprt_net, AF_LOCAL,
1872					SOCK_STREAM, 0, &sock, 1);
1873	if (status < 0) {
1874		dprintk("RPC:       can't create AF_LOCAL "
1875			"transport socket (%d).\n", -status);
1876		goto out;
1877	}
1878	xs_reclassify_socket(AF_LOCAL, sock);
1879
1880	filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1881	if (IS_ERR(filp)) {
1882		status = PTR_ERR(filp);
1883		goto out;
1884	}
1885	transport->file = filp;
1886
1887	dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
1888			xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1889
1890	status = xs_local_finish_connecting(xprt, sock);
1891	trace_rpc_socket_connect(xprt, sock, status);
1892	switch (status) {
1893	case 0:
1894		dprintk("RPC:       xprt %p connected to %s\n",
1895				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1896		xprt->stat.connect_count++;
1897		xprt->stat.connect_time += (long)jiffies -
1898					   xprt->stat.connect_start;
1899		xprt_set_connected(xprt);
1900		break;
1901	case -ENOBUFS:
1902		break;
1903	case -ENOENT:
1904		dprintk("RPC:       xprt %p: socket %s does not exist\n",
1905				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1906		break;
1907	case -ECONNREFUSED:
1908		dprintk("RPC:       xprt %p: connection refused for %s\n",
1909				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1910		break;
1911	default:
1912		printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
1913				__func__, -status,
1914				xprt->address_strings[RPC_DISPLAY_ADDR]);
1915	}
1916
1917out:
1918	xprt_clear_connecting(xprt);
1919	xprt_wake_pending_tasks(xprt, status);
1920	return status;
1921}
1922
1923static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
1924{
1925	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1926	int ret;
1927
1928	 if (RPC_IS_ASYNC(task)) {
 
 
 
1929		/*
1930		 * We want the AF_LOCAL connect to be resolved in the
1931		 * filesystem namespace of the process making the rpc
1932		 * call.  Thus we connect synchronously.
1933		 *
1934		 * If we want to support asynchronous AF_LOCAL calls,
1935		 * we'll need to figure out how to pass a namespace to
1936		 * connect.
1937		 */
1938		task->tk_rpc_status = -ENOTCONN;
1939		rpc_exit(task, -ENOTCONN);
1940		return;
1941	}
1942	ret = xs_local_setup_socket(transport);
1943	if (ret && !RPC_IS_SOFTCONN(task))
1944		msleep_interruptible(15000);
 
 
 
 
 
 
1945}
1946
1947#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
1948/*
1949 * Note that this should be called with XPRT_LOCKED held (or when we otherwise
1950 * know that we have exclusive access to the socket), to guard against
1951 * races with xs_reset_transport.
1952 */
1953static void xs_set_memalloc(struct rpc_xprt *xprt)
1954{
1955	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1956			xprt);
1957
1958	/*
1959	 * If there's no sock, then we have nothing to set. The
1960	 * reconnecting process will get it for us.
1961	 */
1962	if (!transport->inet)
1963		return;
1964	if (atomic_read(&xprt->swapper))
1965		sk_set_memalloc(transport->inet);
1966}
1967
1968/**
1969 * xs_enable_swap - Tag this transport as being used for swap.
1970 * @xprt: transport to tag
1971 *
1972 * Take a reference to this transport on behalf of the rpc_clnt, and
1973 * optionally mark it for swapping if it wasn't already.
1974 */
1975static int
1976xs_enable_swap(struct rpc_xprt *xprt)
1977{
1978	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
1979
1980	if (atomic_inc_return(&xprt->swapper) != 1)
1981		return 0;
1982	if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
1983		return -ERESTARTSYS;
1984	if (xs->inet)
1985		sk_set_memalloc(xs->inet);
1986	xprt_release_xprt(xprt, NULL);
1987	return 0;
1988}
1989
1990/**
1991 * xs_disable_swap - Untag this transport as being used for swap.
1992 * @xprt: transport to tag
1993 *
1994 * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
1995 * swapper refcount goes to 0, untag the socket as a memalloc socket.
1996 */
1997static void
1998xs_disable_swap(struct rpc_xprt *xprt)
1999{
2000	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2001
2002	if (!atomic_dec_and_test(&xprt->swapper))
2003		return;
2004	if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2005		return;
2006	if (xs->inet)
2007		sk_clear_memalloc(xs->inet);
2008	xprt_release_xprt(xprt, NULL);
2009}
2010#else
2011static void xs_set_memalloc(struct rpc_xprt *xprt)
2012{
2013}
2014
2015static int
2016xs_enable_swap(struct rpc_xprt *xprt)
2017{
2018	return -EINVAL;
2019}
2020
2021static void
2022xs_disable_swap(struct rpc_xprt *xprt)
2023{
2024}
2025#endif
2026
2027static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2028{
2029	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2030
2031	if (!transport->inet) {
2032		struct sock *sk = sock->sk;
2033
2034		write_lock_bh(&sk->sk_callback_lock);
2035
2036		xs_save_old_callbacks(transport, sk);
2037
2038		sk->sk_user_data = xprt;
2039		sk->sk_data_ready = xs_data_ready;
2040		sk->sk_write_space = xs_udp_write_space;
2041		sock_set_flag(sk, SOCK_FASYNC);
2042
2043		xprt_set_connected(xprt);
2044
2045		/* Reset to new socket */
2046		transport->sock = sock;
2047		transport->inet = sk;
2048
2049		xs_set_memalloc(xprt);
2050
2051		write_unlock_bh(&sk->sk_callback_lock);
2052	}
2053	xs_udp_do_set_buffer_size(xprt);
2054
2055	xprt->stat.connect_start = jiffies;
2056}
2057
2058static void xs_udp_setup_socket(struct work_struct *work)
2059{
2060	struct sock_xprt *transport =
2061		container_of(work, struct sock_xprt, connect_worker.work);
2062	struct rpc_xprt *xprt = &transport->xprt;
2063	struct socket *sock;
2064	int status = -EIO;
 
2065
 
 
2066	sock = xs_create_sock(xprt, transport,
2067			xs_addr(xprt)->sa_family, SOCK_DGRAM,
2068			IPPROTO_UDP, false);
2069	if (IS_ERR(sock))
2070		goto out;
2071
2072	dprintk("RPC:       worker connecting xprt %p via %s to "
2073				"%s (port %s)\n", xprt,
2074			xprt->address_strings[RPC_DISPLAY_PROTO],
2075			xprt->address_strings[RPC_DISPLAY_ADDR],
2076			xprt->address_strings[RPC_DISPLAY_PORT]);
2077
2078	xs_udp_finish_connecting(xprt, sock);
2079	trace_rpc_socket_connect(xprt, sock, 0);
2080	status = 0;
2081out:
2082	xprt_clear_connecting(xprt);
2083	xprt_unlock_connect(xprt, transport);
2084	xprt_wake_pending_tasks(xprt, status);
 
2085}
2086
2087/**
2088 * xs_tcp_shutdown - gracefully shut down a TCP socket
2089 * @xprt: transport
2090 *
2091 * Initiates a graceful shutdown of the TCP socket by calling the
2092 * equivalent of shutdown(SHUT_RDWR);
2093 */
2094static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2095{
2096	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2097	struct socket *sock = transport->sock;
2098	int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
2099
2100	if (sock == NULL)
2101		return;
 
 
 
 
2102	switch (skst) {
2103	default:
 
 
 
 
2104		kernel_sock_shutdown(sock, SHUT_RDWR);
2105		trace_rpc_socket_shutdown(xprt, sock);
2106		break;
2107	case TCP_CLOSE:
2108	case TCP_TIME_WAIT:
2109		xs_reset_transport(transport);
2110	}
2111}
2112
2113static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
2114		struct socket *sock)
2115{
2116	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2117	unsigned int keepidle;
2118	unsigned int keepcnt;
2119	unsigned int timeo;
2120
2121	spin_lock(&xprt->transport_lock);
2122	keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
2123	keepcnt = xprt->timeout->to_retries + 1;
2124	timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2125		(xprt->timeout->to_retries + 1);
2126	clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2127	spin_unlock(&xprt->transport_lock);
2128
2129	/* TCP Keepalive options */
2130	sock_set_keepalive(sock->sk);
2131	tcp_sock_set_keepidle(sock->sk, keepidle);
2132	tcp_sock_set_keepintvl(sock->sk, keepidle);
2133	tcp_sock_set_keepcnt(sock->sk, keepcnt);
2134
2135	/* TCP user timeout (see RFC5482) */
2136	tcp_sock_set_user_timeout(sock->sk, timeo);
2137}
2138
2139static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
2140		unsigned long connect_timeout,
2141		unsigned long reconnect_timeout)
2142{
2143	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2144	struct rpc_timeout to;
2145	unsigned long initval;
2146
2147	spin_lock(&xprt->transport_lock);
2148	if (reconnect_timeout < xprt->max_reconnect_timeout)
2149		xprt->max_reconnect_timeout = reconnect_timeout;
2150	if (connect_timeout < xprt->connect_timeout) {
2151		memcpy(&to, xprt->timeout, sizeof(to));
2152		initval = DIV_ROUND_UP(connect_timeout, to.to_retries + 1);
2153		/* Arbitrary lower limit */
2154		if (initval <  XS_TCP_INIT_REEST_TO << 1)
2155			initval = XS_TCP_INIT_REEST_TO << 1;
2156		to.to_initval = initval;
2157		to.to_maxval = initval;
2158		memcpy(&transport->tcp_timeout, &to,
2159				sizeof(transport->tcp_timeout));
2160		xprt->timeout = &transport->tcp_timeout;
2161		xprt->connect_timeout = connect_timeout;
2162	}
2163	set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2164	spin_unlock(&xprt->transport_lock);
2165}
2166
2167static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2168{
2169	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2170	int ret = -ENOTCONN;
2171
2172	if (!transport->inet) {
2173		struct sock *sk = sock->sk;
2174
2175		/* Avoid temporary address, they are bad for long-lived
2176		 * connections such as NFS mounts.
2177		 * RFC4941, section 3.6 suggests that:
2178		 *    Individual applications, which have specific
2179		 *    knowledge about the normal duration of connections,
2180		 *    MAY override this as appropriate.
2181		 */
2182		if (xs_addr(xprt)->sa_family == PF_INET6) {
2183			ip6_sock_set_addr_preferences(sk,
2184				IPV6_PREFER_SRC_PUBLIC);
2185		}
2186
2187		xs_tcp_set_socket_timeouts(xprt, sock);
2188		tcp_sock_set_nodelay(sk);
2189
2190		write_lock_bh(&sk->sk_callback_lock);
2191
2192		xs_save_old_callbacks(transport, sk);
2193
2194		sk->sk_user_data = xprt;
2195		sk->sk_data_ready = xs_data_ready;
2196		sk->sk_state_change = xs_tcp_state_change;
2197		sk->sk_write_space = xs_tcp_write_space;
2198		sock_set_flag(sk, SOCK_FASYNC);
2199		sk->sk_error_report = xs_error_report;
 
2200
2201		/* socket options */
2202		sock_reset_flag(sk, SOCK_LINGER);
2203
2204		xprt_clear_connected(xprt);
2205
2206		/* Reset to new socket */
2207		transport->sock = sock;
2208		transport->inet = sk;
2209
2210		write_unlock_bh(&sk->sk_callback_lock);
2211	}
2212
2213	if (!xprt_bound(xprt))
2214		goto out;
2215
2216	xs_set_memalloc(xprt);
2217
2218	xs_stream_start_connect(transport);
2219
2220	/* Tell the socket layer to start connecting... */
2221	set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2222	ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2223	switch (ret) {
2224	case 0:
2225		xs_set_srcport(transport, sock);
2226		fallthrough;
2227	case -EINPROGRESS:
2228		/* SYN_SENT! */
2229		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2230			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2231		break;
2232	case -EADDRNOTAVAIL:
2233		/* Source port number is unavailable. Try a new one! */
2234		transport->srcport = 0;
2235	}
2236out:
2237	return ret;
2238}
2239
2240/**
2241 * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2242 * @work: queued work item
2243 *
2244 * Invoked by a work queue tasklet.
2245 */
2246static void xs_tcp_setup_socket(struct work_struct *work)
2247{
2248	struct sock_xprt *transport =
2249		container_of(work, struct sock_xprt, connect_worker.work);
2250	struct socket *sock = transport->sock;
2251	struct rpc_xprt *xprt = &transport->xprt;
2252	int status = -EIO;
 
 
 
 
2253
2254	if (!sock) {
2255		sock = xs_create_sock(xprt, transport,
2256				xs_addr(xprt)->sa_family, SOCK_STREAM,
2257				IPPROTO_TCP, true);
 
 
 
 
2258		if (IS_ERR(sock)) {
2259			status = PTR_ERR(sock);
2260			goto out;
2261		}
2262	}
2263
2264	dprintk("RPC:       worker connecting xprt %p via %s to "
2265				"%s (port %s)\n", xprt,
2266			xprt->address_strings[RPC_DISPLAY_PROTO],
2267			xprt->address_strings[RPC_DISPLAY_ADDR],
2268			xprt->address_strings[RPC_DISPLAY_PORT]);
2269
2270	status = xs_tcp_finish_connecting(xprt, sock);
2271	trace_rpc_socket_connect(xprt, sock, status);
2272	dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2273			xprt, -status, xprt_connected(xprt),
2274			sock->sk->sk_state);
2275	switch (status) {
2276	default:
2277		printk("%s: connect returned unhandled error %d\n",
2278			__func__, status);
 
 
 
2279		fallthrough;
 
 
2280	case -EADDRNOTAVAIL:
2281		/* We're probably in TIME_WAIT. Get rid of existing socket,
2282		 * and retry
2283		 */
2284		xs_tcp_force_close(xprt);
2285		break;
2286	case 0:
2287	case -EINPROGRESS:
2288	case -EALREADY:
2289		xprt_unlock_connect(xprt, transport);
2290		return;
2291	case -EINVAL:
2292		/* Happens, for instance, if the user specified a link
2293		 * local IPv6 address without a scope-id.
2294		 */
2295	case -ECONNREFUSED:
2296	case -ECONNRESET:
2297	case -ENETDOWN:
2298	case -ENETUNREACH:
2299	case -EHOSTUNREACH:
2300	case -EADDRINUSE:
2301	case -ENOBUFS:
2302		/* xs_tcp_force_close() wakes tasks with a fixed error code.
2303		 * We need to wake them first to ensure the correct error code.
2304		 */
2305		xprt_wake_pending_tasks(xprt, status);
2306		xs_tcp_force_close(xprt);
2307		goto out;
2308	}
2309	status = -EAGAIN;
 
 
 
 
 
2310out:
2311	xprt_clear_connecting(xprt);
 
2312	xprt_unlock_connect(xprt, transport);
2313	xprt_wake_pending_tasks(xprt, status);
2314}
2315
2316/**
2317 * xs_connect - connect a socket to a remote endpoint
2318 * @xprt: pointer to transport structure
2319 * @task: address of RPC task that manages state of connect request
2320 *
2321 * TCP: If the remote end dropped the connection, delay reconnecting.
2322 *
2323 * UDP socket connects are synchronous, but we use a work queue anyway
2324 * to guarantee that even unprivileged user processes can set up a
2325 * socket on a privileged port.
2326 *
2327 * If a UDP socket connect fails, the delay behavior here prevents
2328 * retry floods (hard mounts).
2329 */
2330static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2331{
2332	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2333	unsigned long delay = 0;
2334
2335	WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2336
2337	if (transport->sock != NULL) {
2338		dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2339				"seconds\n",
2340				xprt, xprt->reestablish_timeout / HZ);
2341
2342		/* Start by resetting any existing state */
2343		xs_reset_transport(transport);
2344
2345		delay = xprt_reconnect_delay(xprt);
2346		xprt_reconnect_backoff(xprt, XS_TCP_INIT_REEST_TO);
2347
2348	} else
2349		dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2350
2351	queue_delayed_work(xprtiod_workqueue,
2352			&transport->connect_worker,
2353			delay);
2354}
2355
2356static void xs_wake_disconnect(struct sock_xprt *transport)
2357{
2358	if (test_and_clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state))
2359		xs_tcp_force_close(&transport->xprt);
2360}
2361
2362static void xs_wake_write(struct sock_xprt *transport)
2363{
2364	if (test_and_clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state))
2365		xprt_write_space(&transport->xprt);
2366}
2367
2368static void xs_wake_error(struct sock_xprt *transport)
2369{
2370	int sockerr;
2371
2372	if (!test_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2373		return;
2374	mutex_lock(&transport->recv_mutex);
2375	if (transport->sock == NULL)
2376		goto out;
2377	if (!test_and_clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2378		goto out;
2379	sockerr = xchg(&transport->xprt_err, 0);
2380	if (sockerr < 0)
2381		xprt_wake_pending_tasks(&transport->xprt, sockerr);
2382out:
2383	mutex_unlock(&transport->recv_mutex);
2384}
2385
2386static void xs_wake_pending(struct sock_xprt *transport)
2387{
2388	if (test_and_clear_bit(XPRT_SOCK_WAKE_PENDING, &transport->sock_state))
2389		xprt_wake_pending_tasks(&transport->xprt, -EAGAIN);
2390}
2391
2392static void xs_error_handle(struct work_struct *work)
2393{
2394	struct sock_xprt *transport = container_of(work,
2395			struct sock_xprt, error_worker);
2396
2397	xs_wake_disconnect(transport);
2398	xs_wake_write(transport);
2399	xs_wake_error(transport);
2400	xs_wake_pending(transport);
2401}
2402
2403/**
2404 * xs_local_print_stats - display AF_LOCAL socket-specific stats
2405 * @xprt: rpc_xprt struct containing statistics
2406 * @seq: output file
2407 *
2408 */
2409static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2410{
2411	long idle_time = 0;
2412
2413	if (xprt_connected(xprt))
2414		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2415
2416	seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2417			"%llu %llu %lu %llu %llu\n",
2418			xprt->stat.bind_count,
2419			xprt->stat.connect_count,
2420			xprt->stat.connect_time / HZ,
2421			idle_time,
2422			xprt->stat.sends,
2423			xprt->stat.recvs,
2424			xprt->stat.bad_xids,
2425			xprt->stat.req_u,
2426			xprt->stat.bklog_u,
2427			xprt->stat.max_slots,
2428			xprt->stat.sending_u,
2429			xprt->stat.pending_u);
2430}
2431
2432/**
2433 * xs_udp_print_stats - display UDP socket-specific stats
2434 * @xprt: rpc_xprt struct containing statistics
2435 * @seq: output file
2436 *
2437 */
2438static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2439{
2440	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2441
2442	seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2443			"%lu %llu %llu\n",
2444			transport->srcport,
2445			xprt->stat.bind_count,
2446			xprt->stat.sends,
2447			xprt->stat.recvs,
2448			xprt->stat.bad_xids,
2449			xprt->stat.req_u,
2450			xprt->stat.bklog_u,
2451			xprt->stat.max_slots,
2452			xprt->stat.sending_u,
2453			xprt->stat.pending_u);
2454}
2455
2456/**
2457 * xs_tcp_print_stats - display TCP socket-specific stats
2458 * @xprt: rpc_xprt struct containing statistics
2459 * @seq: output file
2460 *
2461 */
2462static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2463{
2464	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2465	long idle_time = 0;
2466
2467	if (xprt_connected(xprt))
2468		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2469
2470	seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2471			"%llu %llu %lu %llu %llu\n",
2472			transport->srcport,
2473			xprt->stat.bind_count,
2474			xprt->stat.connect_count,
2475			xprt->stat.connect_time / HZ,
2476			idle_time,
2477			xprt->stat.sends,
2478			xprt->stat.recvs,
2479			xprt->stat.bad_xids,
2480			xprt->stat.req_u,
2481			xprt->stat.bklog_u,
2482			xprt->stat.max_slots,
2483			xprt->stat.sending_u,
2484			xprt->stat.pending_u);
2485}
2486
2487/*
2488 * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2489 * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2490 * to use the server side send routines.
2491 */
2492static int bc_malloc(struct rpc_task *task)
2493{
2494	struct rpc_rqst *rqst = task->tk_rqstp;
2495	size_t size = rqst->rq_callsize;
2496	struct page *page;
2497	struct rpc_buffer *buf;
2498
2499	if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2500		WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2501			  size);
2502		return -EINVAL;
2503	}
2504
2505	page = alloc_page(GFP_KERNEL);
2506	if (!page)
2507		return -ENOMEM;
2508
2509	buf = page_address(page);
2510	buf->len = PAGE_SIZE;
2511
2512	rqst->rq_buffer = buf->data;
2513	rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2514	return 0;
2515}
2516
2517/*
2518 * Free the space allocated in the bc_alloc routine
2519 */
2520static void bc_free(struct rpc_task *task)
2521{
2522	void *buffer = task->tk_rqstp->rq_buffer;
2523	struct rpc_buffer *buf;
2524
2525	buf = container_of(buffer, struct rpc_buffer, data);
2526	free_page((unsigned long)buf);
2527}
2528
2529static int bc_sendto(struct rpc_rqst *req)
2530{
2531	struct xdr_buf *xdr = &req->rq_snd_buf;
2532	struct sock_xprt *transport =
2533			container_of(req->rq_xprt, struct sock_xprt, xprt);
2534	struct msghdr msg = {
2535		.msg_flags	= 0,
2536	};
2537	rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT |
2538					 (u32)xdr->len);
2539	unsigned int sent = 0;
2540	int err;
2541
2542	req->rq_xtime = ktime_get();
 
 
 
2543	err = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, marker, &sent);
2544	xdr_free_bvec(xdr);
2545	if (err < 0 || sent != (xdr->len + sizeof(marker)))
2546		return -EAGAIN;
2547	return sent;
2548}
2549
2550/**
2551 * bc_send_request - Send a backchannel Call on a TCP socket
2552 * @req: rpc_rqst containing Call message to be sent
2553 *
2554 * xpt_mutex ensures @rqstp's whole message is written to the socket
2555 * without interruption.
2556 *
2557 * Return values:
2558 *   %0 if the message was sent successfully
2559 *   %ENOTCONN if the message was not sent
2560 */
2561static int bc_send_request(struct rpc_rqst *req)
2562{
2563	struct svc_xprt	*xprt;
2564	int len;
2565
2566	/*
2567	 * Get the server socket associated with this callback xprt
2568	 */
2569	xprt = req->rq_xprt->bc_xprt;
2570
2571	/*
2572	 * Grab the mutex to serialize data as the connection is shared
2573	 * with the fore channel
2574	 */
2575	mutex_lock(&xprt->xpt_mutex);
2576	if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2577		len = -ENOTCONN;
2578	else
2579		len = bc_sendto(req);
2580	mutex_unlock(&xprt->xpt_mutex);
2581
2582	if (len > 0)
2583		len = 0;
2584
2585	return len;
2586}
2587
2588/*
2589 * The close routine. Since this is client initiated, we do nothing
2590 */
2591
2592static void bc_close(struct rpc_xprt *xprt)
2593{
2594	xprt_disconnect_done(xprt);
2595}
2596
2597/*
2598 * The xprt destroy routine. Again, because this connection is client
2599 * initiated, we do nothing
2600 */
2601
2602static void bc_destroy(struct rpc_xprt *xprt)
2603{
2604	dprintk("RPC:       bc_destroy xprt %p\n", xprt);
2605
2606	xs_xprt_free(xprt);
2607	module_put(THIS_MODULE);
2608}
2609
2610static const struct rpc_xprt_ops xs_local_ops = {
2611	.reserve_xprt		= xprt_reserve_xprt,
2612	.release_xprt		= xprt_release_xprt,
2613	.alloc_slot		= xprt_alloc_slot,
2614	.free_slot		= xprt_free_slot,
2615	.rpcbind		= xs_local_rpcbind,
2616	.set_port		= xs_local_set_port,
2617	.connect		= xs_local_connect,
2618	.buf_alloc		= rpc_malloc,
2619	.buf_free		= rpc_free,
2620	.prepare_request	= xs_stream_prepare_request,
2621	.send_request		= xs_local_send_request,
2622	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
2623	.close			= xs_close,
2624	.destroy		= xs_destroy,
2625	.print_stats		= xs_local_print_stats,
2626	.enable_swap		= xs_enable_swap,
2627	.disable_swap		= xs_disable_swap,
2628};
2629
2630static const struct rpc_xprt_ops xs_udp_ops = {
2631	.set_buffer_size	= xs_udp_set_buffer_size,
2632	.reserve_xprt		= xprt_reserve_xprt_cong,
2633	.release_xprt		= xprt_release_xprt_cong,
2634	.alloc_slot		= xprt_alloc_slot,
2635	.free_slot		= xprt_free_slot,
2636	.rpcbind		= rpcb_getport_async,
2637	.set_port		= xs_set_port,
2638	.connect		= xs_connect,
 
 
2639	.buf_alloc		= rpc_malloc,
2640	.buf_free		= rpc_free,
2641	.send_request		= xs_udp_send_request,
2642	.wait_for_reply_request	= xprt_wait_for_reply_request_rtt,
2643	.timer			= xs_udp_timer,
2644	.release_request	= xprt_release_rqst_cong,
2645	.close			= xs_close,
2646	.destroy		= xs_destroy,
2647	.print_stats		= xs_udp_print_stats,
2648	.enable_swap		= xs_enable_swap,
2649	.disable_swap		= xs_disable_swap,
2650	.inject_disconnect	= xs_inject_disconnect,
2651};
2652
2653static const struct rpc_xprt_ops xs_tcp_ops = {
2654	.reserve_xprt		= xprt_reserve_xprt,
2655	.release_xprt		= xprt_release_xprt,
2656	.alloc_slot		= xprt_alloc_slot,
2657	.free_slot		= xprt_free_slot,
2658	.rpcbind		= rpcb_getport_async,
2659	.set_port		= xs_set_port,
2660	.connect		= xs_connect,
 
 
2661	.buf_alloc		= rpc_malloc,
2662	.buf_free		= rpc_free,
2663	.prepare_request	= xs_stream_prepare_request,
2664	.send_request		= xs_tcp_send_request,
2665	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
2666	.close			= xs_tcp_shutdown,
2667	.destroy		= xs_destroy,
2668	.set_connect_timeout	= xs_tcp_set_connect_timeout,
2669	.print_stats		= xs_tcp_print_stats,
2670	.enable_swap		= xs_enable_swap,
2671	.disable_swap		= xs_disable_swap,
2672	.inject_disconnect	= xs_inject_disconnect,
2673#ifdef CONFIG_SUNRPC_BACKCHANNEL
2674	.bc_setup		= xprt_setup_bc,
2675	.bc_maxpayload		= xs_tcp_bc_maxpayload,
2676	.bc_num_slots		= xprt_bc_max_slots,
2677	.bc_free_rqst		= xprt_free_bc_rqst,
2678	.bc_destroy		= xprt_destroy_bc,
2679#endif
2680};
2681
2682/*
2683 * The rpc_xprt_ops for the server backchannel
2684 */
2685
2686static const struct rpc_xprt_ops bc_tcp_ops = {
2687	.reserve_xprt		= xprt_reserve_xprt,
2688	.release_xprt		= xprt_release_xprt,
2689	.alloc_slot		= xprt_alloc_slot,
2690	.free_slot		= xprt_free_slot,
2691	.buf_alloc		= bc_malloc,
2692	.buf_free		= bc_free,
2693	.send_request		= bc_send_request,
2694	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
2695	.close			= bc_close,
2696	.destroy		= bc_destroy,
2697	.print_stats		= xs_tcp_print_stats,
2698	.enable_swap		= xs_enable_swap,
2699	.disable_swap		= xs_disable_swap,
2700	.inject_disconnect	= xs_inject_disconnect,
2701};
2702
2703static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2704{
2705	static const struct sockaddr_in sin = {
2706		.sin_family		= AF_INET,
2707		.sin_addr.s_addr	= htonl(INADDR_ANY),
2708	};
2709	static const struct sockaddr_in6 sin6 = {
2710		.sin6_family		= AF_INET6,
2711		.sin6_addr		= IN6ADDR_ANY_INIT,
2712	};
2713
2714	switch (family) {
2715	case AF_LOCAL:
2716		break;
2717	case AF_INET:
2718		memcpy(sap, &sin, sizeof(sin));
2719		break;
2720	case AF_INET6:
2721		memcpy(sap, &sin6, sizeof(sin6));
2722		break;
2723	default:
2724		dprintk("RPC:       %s: Bad address family\n", __func__);
2725		return -EAFNOSUPPORT;
2726	}
2727	return 0;
2728}
2729
2730static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2731				      unsigned int slot_table_size,
2732				      unsigned int max_slot_table_size)
2733{
2734	struct rpc_xprt *xprt;
2735	struct sock_xprt *new;
2736
2737	if (args->addrlen > sizeof(xprt->addr)) {
2738		dprintk("RPC:       xs_setup_xprt: address too large\n");
2739		return ERR_PTR(-EBADF);
2740	}
2741
2742	xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2743			max_slot_table_size);
2744	if (xprt == NULL) {
2745		dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2746				"rpc_xprt\n");
2747		return ERR_PTR(-ENOMEM);
2748	}
2749
2750	new = container_of(xprt, struct sock_xprt, xprt);
2751	mutex_init(&new->recv_mutex);
2752	memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2753	xprt->addrlen = args->addrlen;
2754	if (args->srcaddr)
2755		memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2756	else {
2757		int err;
2758		err = xs_init_anyaddr(args->dstaddr->sa_family,
2759					(struct sockaddr *)&new->srcaddr);
2760		if (err != 0) {
2761			xprt_free(xprt);
2762			return ERR_PTR(err);
2763		}
2764	}
2765
2766	return xprt;
2767}
2768
2769static const struct rpc_timeout xs_local_default_timeout = {
2770	.to_initval = 10 * HZ,
2771	.to_maxval = 10 * HZ,
2772	.to_retries = 2,
2773};
2774
2775/**
2776 * xs_setup_local - Set up transport to use an AF_LOCAL socket
2777 * @args: rpc transport creation arguments
2778 *
2779 * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2780 */
2781static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2782{
2783	struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2784	struct sock_xprt *transport;
2785	struct rpc_xprt *xprt;
2786	struct rpc_xprt *ret;
2787
2788	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2789			xprt_max_tcp_slot_table_entries);
2790	if (IS_ERR(xprt))
2791		return xprt;
2792	transport = container_of(xprt, struct sock_xprt, xprt);
2793
2794	xprt->prot = 0;
2795	xprt->xprt_class = &xs_local_transport;
2796	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2797
2798	xprt->bind_timeout = XS_BIND_TO;
2799	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2800	xprt->idle_timeout = XS_IDLE_DISC_TO;
2801
2802	xprt->ops = &xs_local_ops;
2803	xprt->timeout = &xs_local_default_timeout;
2804
2805	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2806	INIT_WORK(&transport->error_worker, xs_error_handle);
2807	INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket);
2808
2809	switch (sun->sun_family) {
2810	case AF_LOCAL:
2811		if (sun->sun_path[0] != '/') {
2812			dprintk("RPC:       bad AF_LOCAL address: %s\n",
2813					sun->sun_path);
2814			ret = ERR_PTR(-EINVAL);
2815			goto out_err;
2816		}
2817		xprt_set_bound(xprt);
2818		xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
2819		ret = ERR_PTR(xs_local_setup_socket(transport));
2820		if (ret)
2821			goto out_err;
2822		break;
2823	default:
2824		ret = ERR_PTR(-EAFNOSUPPORT);
2825		goto out_err;
2826	}
2827
2828	dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
2829			xprt->address_strings[RPC_DISPLAY_ADDR]);
2830
2831	if (try_module_get(THIS_MODULE))
2832		return xprt;
2833	ret = ERR_PTR(-EINVAL);
2834out_err:
2835	xs_xprt_free(xprt);
2836	return ret;
2837}
2838
2839static const struct rpc_timeout xs_udp_default_timeout = {
2840	.to_initval = 5 * HZ,
2841	.to_maxval = 30 * HZ,
2842	.to_increment = 5 * HZ,
2843	.to_retries = 5,
2844};
2845
2846/**
2847 * xs_setup_udp - Set up transport to use a UDP socket
2848 * @args: rpc transport creation arguments
2849 *
2850 */
2851static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2852{
2853	struct sockaddr *addr = args->dstaddr;
2854	struct rpc_xprt *xprt;
2855	struct sock_xprt *transport;
2856	struct rpc_xprt *ret;
2857
2858	xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2859			xprt_udp_slot_table_entries);
2860	if (IS_ERR(xprt))
2861		return xprt;
2862	transport = container_of(xprt, struct sock_xprt, xprt);
2863
2864	xprt->prot = IPPROTO_UDP;
2865	xprt->xprt_class = &xs_udp_transport;
2866	/* XXX: header size can vary due to auth type, IPv6, etc. */
2867	xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2868
2869	xprt->bind_timeout = XS_BIND_TO;
2870	xprt->reestablish_timeout = XS_UDP_REEST_TO;
2871	xprt->idle_timeout = XS_IDLE_DISC_TO;
2872
2873	xprt->ops = &xs_udp_ops;
2874
2875	xprt->timeout = &xs_udp_default_timeout;
2876
2877	INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
2878	INIT_WORK(&transport->error_worker, xs_error_handle);
2879	INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
2880
2881	switch (addr->sa_family) {
2882	case AF_INET:
2883		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2884			xprt_set_bound(xprt);
2885
2886		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2887		break;
2888	case AF_INET6:
2889		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2890			xprt_set_bound(xprt);
2891
2892		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2893		break;
2894	default:
2895		ret = ERR_PTR(-EAFNOSUPPORT);
2896		goto out_err;
2897	}
2898
2899	if (xprt_bound(xprt))
2900		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2901				xprt->address_strings[RPC_DISPLAY_ADDR],
2902				xprt->address_strings[RPC_DISPLAY_PORT],
2903				xprt->address_strings[RPC_DISPLAY_PROTO]);
2904	else
2905		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2906				xprt->address_strings[RPC_DISPLAY_ADDR],
2907				xprt->address_strings[RPC_DISPLAY_PROTO]);
2908
2909	if (try_module_get(THIS_MODULE))
2910		return xprt;
2911	ret = ERR_PTR(-EINVAL);
2912out_err:
2913	xs_xprt_free(xprt);
2914	return ret;
2915}
2916
2917static const struct rpc_timeout xs_tcp_default_timeout = {
2918	.to_initval = 60 * HZ,
2919	.to_maxval = 60 * HZ,
2920	.to_retries = 2,
2921};
2922
2923/**
2924 * xs_setup_tcp - Set up transport to use a TCP socket
2925 * @args: rpc transport creation arguments
2926 *
2927 */
2928static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2929{
2930	struct sockaddr *addr = args->dstaddr;
2931	struct rpc_xprt *xprt;
2932	struct sock_xprt *transport;
2933	struct rpc_xprt *ret;
2934	unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
2935
2936	if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
2937		max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
2938
2939	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2940			max_slot_table_size);
2941	if (IS_ERR(xprt))
2942		return xprt;
2943	transport = container_of(xprt, struct sock_xprt, xprt);
2944
2945	xprt->prot = IPPROTO_TCP;
2946	xprt->xprt_class = &xs_tcp_transport;
2947	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2948
2949	xprt->bind_timeout = XS_BIND_TO;
2950	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2951	xprt->idle_timeout = XS_IDLE_DISC_TO;
2952
2953	xprt->ops = &xs_tcp_ops;
2954	xprt->timeout = &xs_tcp_default_timeout;
2955
2956	xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
2957	xprt->connect_timeout = xprt->timeout->to_initval *
2958		(xprt->timeout->to_retries + 1);
2959
2960	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2961	INIT_WORK(&transport->error_worker, xs_error_handle);
2962	INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
2963
2964	switch (addr->sa_family) {
2965	case AF_INET:
2966		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2967			xprt_set_bound(xprt);
2968
2969		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
2970		break;
2971	case AF_INET6:
2972		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2973			xprt_set_bound(xprt);
2974
2975		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
2976		break;
2977	default:
2978		ret = ERR_PTR(-EAFNOSUPPORT);
2979		goto out_err;
2980	}
2981
2982	if (xprt_bound(xprt))
2983		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2984				xprt->address_strings[RPC_DISPLAY_ADDR],
2985				xprt->address_strings[RPC_DISPLAY_PORT],
2986				xprt->address_strings[RPC_DISPLAY_PROTO]);
2987	else
2988		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2989				xprt->address_strings[RPC_DISPLAY_ADDR],
2990				xprt->address_strings[RPC_DISPLAY_PROTO]);
2991
2992	if (try_module_get(THIS_MODULE))
2993		return xprt;
2994	ret = ERR_PTR(-EINVAL);
2995out_err:
2996	xs_xprt_free(xprt);
2997	return ret;
2998}
2999
3000/**
3001 * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
3002 * @args: rpc transport creation arguments
3003 *
3004 */
3005static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
3006{
3007	struct sockaddr *addr = args->dstaddr;
3008	struct rpc_xprt *xprt;
3009	struct sock_xprt *transport;
3010	struct svc_sock *bc_sock;
3011	struct rpc_xprt *ret;
3012
3013	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3014			xprt_tcp_slot_table_entries);
3015	if (IS_ERR(xprt))
3016		return xprt;
3017	transport = container_of(xprt, struct sock_xprt, xprt);
3018
3019	xprt->prot = IPPROTO_TCP;
3020	xprt->xprt_class = &xs_bc_tcp_transport;
3021	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3022	xprt->timeout = &xs_tcp_default_timeout;
3023
3024	/* backchannel */
3025	xprt_set_bound(xprt);
3026	xprt->bind_timeout = 0;
3027	xprt->reestablish_timeout = 0;
3028	xprt->idle_timeout = 0;
3029
3030	xprt->ops = &bc_tcp_ops;
3031
3032	switch (addr->sa_family) {
3033	case AF_INET:
3034		xs_format_peer_addresses(xprt, "tcp",
3035					 RPCBIND_NETID_TCP);
3036		break;
3037	case AF_INET6:
3038		xs_format_peer_addresses(xprt, "tcp",
3039				   RPCBIND_NETID_TCP6);
3040		break;
3041	default:
3042		ret = ERR_PTR(-EAFNOSUPPORT);
3043		goto out_err;
3044	}
3045
3046	dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3047			xprt->address_strings[RPC_DISPLAY_ADDR],
3048			xprt->address_strings[RPC_DISPLAY_PORT],
3049			xprt->address_strings[RPC_DISPLAY_PROTO]);
3050
3051	/*
3052	 * Once we've associated a backchannel xprt with a connection,
3053	 * we want to keep it around as long as the connection lasts,
3054	 * in case we need to start using it for a backchannel again;
3055	 * this reference won't be dropped until bc_xprt is destroyed.
3056	 */
3057	xprt_get(xprt);
3058	args->bc_xprt->xpt_bc_xprt = xprt;
3059	xprt->bc_xprt = args->bc_xprt;
3060	bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3061	transport->sock = bc_sock->sk_sock;
3062	transport->inet = bc_sock->sk_sk;
3063
3064	/*
3065	 * Since we don't want connections for the backchannel, we set
3066	 * the xprt status to connected
3067	 */
3068	xprt_set_connected(xprt);
3069
3070	if (try_module_get(THIS_MODULE))
3071		return xprt;
3072
3073	args->bc_xprt->xpt_bc_xprt = NULL;
3074	args->bc_xprt->xpt_bc_xps = NULL;
3075	xprt_put(xprt);
3076	ret = ERR_PTR(-EINVAL);
3077out_err:
3078	xs_xprt_free(xprt);
3079	return ret;
3080}
3081
3082static struct xprt_class	xs_local_transport = {
3083	.list		= LIST_HEAD_INIT(xs_local_transport.list),
3084	.name		= "named UNIX socket",
3085	.owner		= THIS_MODULE,
3086	.ident		= XPRT_TRANSPORT_LOCAL,
3087	.setup		= xs_setup_local,
3088	.netid		= { "" },
3089};
3090
3091static struct xprt_class	xs_udp_transport = {
3092	.list		= LIST_HEAD_INIT(xs_udp_transport.list),
3093	.name		= "udp",
3094	.owner		= THIS_MODULE,
3095	.ident		= XPRT_TRANSPORT_UDP,
3096	.setup		= xs_setup_udp,
3097	.netid		= { "udp", "udp6", "" },
3098};
3099
3100static struct xprt_class	xs_tcp_transport = {
3101	.list		= LIST_HEAD_INIT(xs_tcp_transport.list),
3102	.name		= "tcp",
3103	.owner		= THIS_MODULE,
3104	.ident		= XPRT_TRANSPORT_TCP,
3105	.setup		= xs_setup_tcp,
3106	.netid		= { "tcp", "tcp6", "" },
3107};
3108
3109static struct xprt_class	xs_bc_tcp_transport = {
3110	.list		= LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3111	.name		= "tcp NFSv4.1 backchannel",
3112	.owner		= THIS_MODULE,
3113	.ident		= XPRT_TRANSPORT_BC_TCP,
3114	.setup		= xs_setup_bc_tcp,
3115	.netid		= { "" },
3116};
3117
3118/**
3119 * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3120 *
3121 */
3122int init_socket_xprt(void)
3123{
3124	if (!sunrpc_table_header)
3125		sunrpc_table_header = register_sysctl_table(sunrpc_table);
3126
3127	xprt_register_transport(&xs_local_transport);
3128	xprt_register_transport(&xs_udp_transport);
3129	xprt_register_transport(&xs_tcp_transport);
3130	xprt_register_transport(&xs_bc_tcp_transport);
3131
3132	return 0;
3133}
3134
3135/**
3136 * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3137 *
3138 */
3139void cleanup_socket_xprt(void)
3140{
3141	if (sunrpc_table_header) {
3142		unregister_sysctl_table(sunrpc_table_header);
3143		sunrpc_table_header = NULL;
3144	}
3145
3146	xprt_unregister_transport(&xs_local_transport);
3147	xprt_unregister_transport(&xs_udp_transport);
3148	xprt_unregister_transport(&xs_tcp_transport);
3149	xprt_unregister_transport(&xs_bc_tcp_transport);
3150}
3151
3152static int param_set_uint_minmax(const char *val,
3153		const struct kernel_param *kp,
3154		unsigned int min, unsigned int max)
3155{
3156	unsigned int num;
3157	int ret;
3158
3159	if (!val)
3160		return -EINVAL;
3161	ret = kstrtouint(val, 0, &num);
3162	if (ret)
3163		return ret;
3164	if (num < min || num > max)
3165		return -EINVAL;
3166	*((unsigned int *)kp->arg) = num;
3167	return 0;
3168}
3169
3170static int param_set_portnr(const char *val, const struct kernel_param *kp)
3171{
3172	return param_set_uint_minmax(val, kp,
3173			RPC_MIN_RESVPORT,
3174			RPC_MAX_RESVPORT);
3175}
3176
3177static const struct kernel_param_ops param_ops_portnr = {
3178	.set = param_set_portnr,
3179	.get = param_get_uint,
3180};
3181
3182#define param_check_portnr(name, p) \
3183	__param_check(name, p, unsigned int);
3184
3185module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3186module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3187
3188static int param_set_slot_table_size(const char *val,
3189				     const struct kernel_param *kp)
3190{
3191	return param_set_uint_minmax(val, kp,
3192			RPC_MIN_SLOT_TABLE,
3193			RPC_MAX_SLOT_TABLE);
3194}
3195
3196static const struct kernel_param_ops param_ops_slot_table_size = {
3197	.set = param_set_slot_table_size,
3198	.get = param_get_uint,
3199};
3200
3201#define param_check_slot_table_size(name, p) \
3202	__param_check(name, p, unsigned int);
3203
3204static int param_set_max_slot_table_size(const char *val,
3205				     const struct kernel_param *kp)
3206{
3207	return param_set_uint_minmax(val, kp,
3208			RPC_MIN_SLOT_TABLE,
3209			RPC_MAX_SLOT_TABLE_LIMIT);
3210}
3211
3212static const struct kernel_param_ops param_ops_max_slot_table_size = {
3213	.set = param_set_max_slot_table_size,
3214	.get = param_get_uint,
3215};
3216
3217#define param_check_max_slot_table_size(name, p) \
3218	__param_check(name, p, unsigned int);
3219
3220module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3221		   slot_table_size, 0644);
3222module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3223		   max_slot_table_size, 0644);
3224module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3225		   slot_table_size, 0644);