Linux Audio

Check our new training course

Loading...
v5.4
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * linux/net/sunrpc/xprtsock.c
   4 *
   5 * Client-side transport implementation for sockets.
   6 *
   7 * TCP callback races fixes (C) 1998 Red Hat
   8 * TCP send fixes (C) 1998 Red Hat
   9 * TCP NFS related read + write fixes
  10 *  (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
  11 *
  12 * Rewrite of larges part of the code in order to stabilize TCP stuff.
  13 * Fix behaviour when socket buffer is full.
  14 *  (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no>
  15 *
  16 * IP socket transport implementation, (C) 2005 Chuck Lever <cel@netapp.com>
  17 *
  18 * IPv6 support contributed by Gilles Quillard, Bull Open Source, 2005.
  19 *   <gilles.quillard@bull.net>
  20 */
  21
  22#include <linux/types.h>
  23#include <linux/string.h>
  24#include <linux/slab.h>
  25#include <linux/module.h>
  26#include <linux/capability.h>
  27#include <linux/pagemap.h>
  28#include <linux/errno.h>
  29#include <linux/socket.h>
  30#include <linux/in.h>
  31#include <linux/net.h>
  32#include <linux/mm.h>
  33#include <linux/un.h>
  34#include <linux/udp.h>
  35#include <linux/tcp.h>
  36#include <linux/sunrpc/clnt.h>
  37#include <linux/sunrpc/addr.h>
  38#include <linux/sunrpc/sched.h>
  39#include <linux/sunrpc/svcsock.h>
  40#include <linux/sunrpc/xprtsock.h>
  41#include <linux/file.h>
  42#ifdef CONFIG_SUNRPC_BACKCHANNEL
  43#include <linux/sunrpc/bc_xprt.h>
  44#endif
  45
  46#include <net/sock.h>
  47#include <net/checksum.h>
  48#include <net/udp.h>
  49#include <net/tcp.h>
  50#include <linux/bvec.h>
  51#include <linux/highmem.h>
  52#include <linux/uio.h>
  53#include <linux/sched/mm.h>
  54
  55#include <trace/events/sunrpc.h>
  56
  57#include "sunrpc.h"
  58
  59static void xs_close(struct rpc_xprt *xprt);
  60static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
  61		struct socket *sock);
  62
  63/*
  64 * xprtsock tunables
  65 */
  66static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  67static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
  68static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
  69
  70static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
  71static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
  72
 
 
  73#define XS_TCP_LINGER_TO	(15U * HZ)
  74static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
  75
  76/*
  77 * We can register our own files under /proc/sys/sunrpc by
  78 * calling register_sysctl_table() again.  The files in that
  79 * directory become the union of all files registered there.
  80 *
  81 * We simply need to make sure that we don't collide with
  82 * someone else's file names!
  83 */
  84
  85static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
  86static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
  87static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
  88static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
  89static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
  90
  91static struct ctl_table_header *sunrpc_table_header;
  92
  93/*
  94 * FIXME: changing the UDP slot table size should also resize the UDP
  95 *        socket buffers for existing UDP transports
  96 */
  97static struct ctl_table xs_tunables_table[] = {
  98	{
  99		.procname	= "udp_slot_table_entries",
 100		.data		= &xprt_udp_slot_table_entries,
 101		.maxlen		= sizeof(unsigned int),
 102		.mode		= 0644,
 103		.proc_handler	= proc_dointvec_minmax,
 104		.extra1		= &min_slot_table_size,
 105		.extra2		= &max_slot_table_size
 106	},
 107	{
 108		.procname	= "tcp_slot_table_entries",
 109		.data		= &xprt_tcp_slot_table_entries,
 110		.maxlen		= sizeof(unsigned int),
 111		.mode		= 0644,
 112		.proc_handler	= proc_dointvec_minmax,
 113		.extra1		= &min_slot_table_size,
 114		.extra2		= &max_slot_table_size
 115	},
 116	{
 117		.procname	= "tcp_max_slot_table_entries",
 118		.data		= &xprt_max_tcp_slot_table_entries,
 119		.maxlen		= sizeof(unsigned int),
 120		.mode		= 0644,
 121		.proc_handler	= proc_dointvec_minmax,
 122		.extra1		= &min_slot_table_size,
 123		.extra2		= &max_tcp_slot_table_limit
 124	},
 125	{
 126		.procname	= "min_resvport",
 127		.data		= &xprt_min_resvport,
 128		.maxlen		= sizeof(unsigned int),
 129		.mode		= 0644,
 130		.proc_handler	= proc_dointvec_minmax,
 131		.extra1		= &xprt_min_resvport_limit,
 132		.extra2		= &xprt_max_resvport_limit
 133	},
 134	{
 135		.procname	= "max_resvport",
 136		.data		= &xprt_max_resvport,
 137		.maxlen		= sizeof(unsigned int),
 138		.mode		= 0644,
 139		.proc_handler	= proc_dointvec_minmax,
 140		.extra1		= &xprt_min_resvport_limit,
 141		.extra2		= &xprt_max_resvport_limit
 142	},
 143	{
 144		.procname	= "tcp_fin_timeout",
 145		.data		= &xs_tcp_fin_timeout,
 146		.maxlen		= sizeof(xs_tcp_fin_timeout),
 147		.mode		= 0644,
 148		.proc_handler	= proc_dointvec_jiffies,
 149	},
 150	{ },
 151};
 152
 153static struct ctl_table sunrpc_table[] = {
 154	{
 155		.procname	= "sunrpc",
 156		.mode		= 0555,
 157		.child		= xs_tunables_table
 158	},
 159	{ },
 160};
 161
 
 
 162/*
 163 * Wait duration for a reply from the RPC portmapper.
 164 */
 165#define XS_BIND_TO		(60U * HZ)
 166
 167/*
 168 * Delay if a UDP socket connect error occurs.  This is most likely some
 169 * kind of resource problem on the local host.
 170 */
 171#define XS_UDP_REEST_TO		(2U * HZ)
 172
 173/*
 174 * The reestablish timeout allows clients to delay for a bit before attempting
 175 * to reconnect to a server that just dropped our connection.
 176 *
 177 * We implement an exponential backoff when trying to reestablish a TCP
 178 * transport connection with the server.  Some servers like to drop a TCP
 179 * connection when they are overworked, so we start with a short timeout and
 180 * increase over time if the server is down or not responding.
 181 */
 182#define XS_TCP_INIT_REEST_TO	(3U * HZ)
 183
 184/*
 185 * TCP idle timeout; client drops the transport socket if it is idle
 186 * for this long.  Note that we also timeout UDP sockets to prevent
 187 * holding port numbers when there is no RPC traffic.
 188 */
 189#define XS_IDLE_DISC_TO		(5U * 60 * HZ)
 190
 191#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 192# undef  RPC_DEBUG_DATA
 193# define RPCDBG_FACILITY	RPCDBG_TRANS
 194#endif
 195
 196#ifdef RPC_DEBUG_DATA
 197static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 198{
 199	u8 *buf = (u8 *) packet;
 200	int j;
 201
 202	dprintk("RPC:       %s\n", msg);
 203	for (j = 0; j < count && j < 128; j += 4) {
 204		if (!(j & 31)) {
 205			if (j)
 206				dprintk("\n");
 207			dprintk("0x%04x ", j);
 208		}
 209		dprintk("%02x%02x%02x%02x ",
 210			buf[j], buf[j+1], buf[j+2], buf[j+3]);
 211	}
 212	dprintk("\n");
 213}
 214#else
 215static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 216{
 217	/* NOP */
 218}
 219#endif
 220
 221static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
 222{
 223	return (struct rpc_xprt *) sk->sk_user_data;
 224}
 225
 226static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
 227{
 228	return (struct sockaddr *) &xprt->addr;
 229}
 230
 231static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
 232{
 233	return (struct sockaddr_un *) &xprt->addr;
 234}
 235
 236static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
 237{
 238	return (struct sockaddr_in *) &xprt->addr;
 239}
 240
 241static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
 242{
 243	return (struct sockaddr_in6 *) &xprt->addr;
 244}
 245
 246static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
 247{
 248	struct sockaddr *sap = xs_addr(xprt);
 249	struct sockaddr_in6 *sin6;
 250	struct sockaddr_in *sin;
 251	struct sockaddr_un *sun;
 252	char buf[128];
 253
 254	switch (sap->sa_family) {
 255	case AF_LOCAL:
 256		sun = xs_addr_un(xprt);
 257		strlcpy(buf, sun->sun_path, sizeof(buf));
 258		xprt->address_strings[RPC_DISPLAY_ADDR] =
 259						kstrdup(buf, GFP_KERNEL);
 260		break;
 261	case AF_INET:
 262		(void)rpc_ntop(sap, buf, sizeof(buf));
 263		xprt->address_strings[RPC_DISPLAY_ADDR] =
 264						kstrdup(buf, GFP_KERNEL);
 265		sin = xs_addr_in(xprt);
 266		snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
 267		break;
 268	case AF_INET6:
 269		(void)rpc_ntop(sap, buf, sizeof(buf));
 270		xprt->address_strings[RPC_DISPLAY_ADDR] =
 271						kstrdup(buf, GFP_KERNEL);
 272		sin6 = xs_addr_in6(xprt);
 273		snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
 274		break;
 275	default:
 276		BUG();
 277	}
 278
 279	xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
 280}
 281
 282static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
 283{
 284	struct sockaddr *sap = xs_addr(xprt);
 285	char buf[128];
 286
 287	snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
 288	xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
 289
 290	snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
 291	xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
 292}
 293
 294static void xs_format_peer_addresses(struct rpc_xprt *xprt,
 295				     const char *protocol,
 296				     const char *netid)
 297{
 298	xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
 299	xprt->address_strings[RPC_DISPLAY_NETID] = netid;
 300	xs_format_common_peer_addresses(xprt);
 301	xs_format_common_peer_ports(xprt);
 302}
 303
 304static void xs_update_peer_port(struct rpc_xprt *xprt)
 305{
 306	kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
 307	kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
 308
 309	xs_format_common_peer_ports(xprt);
 310}
 311
 312static void xs_free_peer_addresses(struct rpc_xprt *xprt)
 313{
 314	unsigned int i;
 315
 316	for (i = 0; i < RPC_DISPLAY_MAX; i++)
 317		switch (i) {
 318		case RPC_DISPLAY_PROTO:
 319		case RPC_DISPLAY_NETID:
 320			continue;
 321		default:
 322			kfree(xprt->address_strings[i]);
 323		}
 324}
 325
 326static size_t
 327xs_alloc_sparse_pages(struct xdr_buf *buf, size_t want, gfp_t gfp)
 328{
 329	size_t i,n;
 330
 331	if (!want || !(buf->flags & XDRBUF_SPARSE_PAGES))
 332		return want;
 333	n = (buf->page_base + want + PAGE_SIZE - 1) >> PAGE_SHIFT;
 334	for (i = 0; i < n; i++) {
 335		if (buf->pages[i])
 336			continue;
 337		buf->bvec[i].bv_page = buf->pages[i] = alloc_page(gfp);
 338		if (!buf->pages[i]) {
 339			i *= PAGE_SIZE;
 340			return i > buf->page_base ? i - buf->page_base : 0;
 341		}
 342	}
 343	return want;
 344}
 345
 346static ssize_t
 347xs_sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags, size_t seek)
 348{
 349	ssize_t ret;
 350	if (seek != 0)
 351		iov_iter_advance(&msg->msg_iter, seek);
 352	ret = sock_recvmsg(sock, msg, flags);
 353	return ret > 0 ? ret + seek : ret;
 354}
 355
 356static ssize_t
 357xs_read_kvec(struct socket *sock, struct msghdr *msg, int flags,
 358		struct kvec *kvec, size_t count, size_t seek)
 359{
 360	iov_iter_kvec(&msg->msg_iter, READ, kvec, 1, count);
 361	return xs_sock_recvmsg(sock, msg, flags, seek);
 362}
 363
 364static ssize_t
 365xs_read_bvec(struct socket *sock, struct msghdr *msg, int flags,
 366		struct bio_vec *bvec, unsigned long nr, size_t count,
 367		size_t seek)
 368{
 369	iov_iter_bvec(&msg->msg_iter, READ, bvec, nr, count);
 370	return xs_sock_recvmsg(sock, msg, flags, seek);
 371}
 372
 373static ssize_t
 374xs_read_discard(struct socket *sock, struct msghdr *msg, int flags,
 375		size_t count)
 376{
 377	iov_iter_discard(&msg->msg_iter, READ, count);
 378	return sock_recvmsg(sock, msg, flags);
 379}
 380
 381#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
 382static void
 383xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
 384{
 385	struct bvec_iter bi = {
 386		.bi_size = count,
 
 
 387	};
 388	struct bio_vec bv;
 389
 390	bvec_iter_advance(bvec, &bi, seek & PAGE_MASK);
 391	for_each_bvec(bv, bvec, bi, bi)
 392		flush_dcache_page(bv.bv_page);
 393}
 394#else
 395static inline void
 396xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
 397{
 398}
 399#endif
 400
 401static ssize_t
 402xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags,
 403		struct xdr_buf *buf, size_t count, size_t seek, size_t *read)
 404{
 405	size_t want, seek_init = seek, offset = 0;
 406	ssize_t ret;
 407
 408	want = min_t(size_t, count, buf->head[0].iov_len);
 409	if (seek < want) {
 410		ret = xs_read_kvec(sock, msg, flags, &buf->head[0], want, seek);
 411		if (ret <= 0)
 412			goto sock_err;
 413		offset += ret;
 414		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 415			goto out;
 416		if (ret != want)
 417			goto out;
 418		seek = 0;
 419	} else {
 420		seek -= want;
 421		offset += want;
 422	}
 423
 424	want = xs_alloc_sparse_pages(buf,
 425			min_t(size_t, count - offset, buf->page_len),
 426			GFP_KERNEL);
 427	if (seek < want) {
 428		ret = xs_read_bvec(sock, msg, flags, buf->bvec,
 429				xdr_buf_pagecount(buf),
 430				want + buf->page_base,
 431				seek + buf->page_base);
 432		if (ret <= 0)
 433			goto sock_err;
 434		xs_flush_bvec(buf->bvec, ret, seek + buf->page_base);
 435		offset += ret - buf->page_base;
 436		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 437			goto out;
 438		if (ret != want)
 439			goto out;
 440		seek = 0;
 441	} else {
 442		seek -= want;
 443		offset += want;
 444	}
 445
 446	want = min_t(size_t, count - offset, buf->tail[0].iov_len);
 447	if (seek < want) {
 448		ret = xs_read_kvec(sock, msg, flags, &buf->tail[0], want, seek);
 449		if (ret <= 0)
 450			goto sock_err;
 451		offset += ret;
 452		if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 453			goto out;
 454		if (ret != want)
 455			goto out;
 456	} else if (offset < seek_init)
 457		offset = seek_init;
 458	ret = -EMSGSIZE;
 459out:
 460	*read = offset - seek_init;
 461	return ret;
 462sock_err:
 463	offset += seek;
 464	goto out;
 465}
 466
 467static void
 468xs_read_header(struct sock_xprt *transport, struct xdr_buf *buf)
 469{
 470	if (!transport->recv.copied) {
 471		if (buf->head[0].iov_len >= transport->recv.offset)
 472			memcpy(buf->head[0].iov_base,
 473					&transport->recv.xid,
 474					transport->recv.offset);
 475		transport->recv.copied = transport->recv.offset;
 476	}
 477}
 478
 479static bool
 480xs_read_stream_request_done(struct sock_xprt *transport)
 481{
 482	return transport->recv.fraghdr & cpu_to_be32(RPC_LAST_STREAM_FRAGMENT);
 483}
 484
 485static void
 486xs_read_stream_check_eor(struct sock_xprt *transport,
 487		struct msghdr *msg)
 488{
 489	if (xs_read_stream_request_done(transport))
 490		msg->msg_flags |= MSG_EOR;
 491}
 492
 493static ssize_t
 494xs_read_stream_request(struct sock_xprt *transport, struct msghdr *msg,
 495		int flags, struct rpc_rqst *req)
 496{
 497	struct xdr_buf *buf = &req->rq_private_buf;
 498	size_t want, uninitialized_var(read);
 499	ssize_t uninitialized_var(ret);
 500
 501	xs_read_header(transport, buf);
 502
 503	want = transport->recv.len - transport->recv.offset;
 504	if (want != 0) {
 505		ret = xs_read_xdr_buf(transport->sock, msg, flags, buf,
 506				transport->recv.copied + want,
 507				transport->recv.copied,
 508				&read);
 509		transport->recv.offset += read;
 510		transport->recv.copied += read;
 511	}
 512
 513	if (transport->recv.offset == transport->recv.len)
 514		xs_read_stream_check_eor(transport, msg);
 515
 516	if (want == 0)
 517		return 0;
 518
 519	switch (ret) {
 520	default:
 521		break;
 522	case -EFAULT:
 523	case -EMSGSIZE:
 524		msg->msg_flags |= MSG_TRUNC;
 525		return read;
 526	case 0:
 527		return -ESHUTDOWN;
 528	}
 529	return ret < 0 ? ret : read;
 530}
 531
 532static size_t
 533xs_read_stream_headersize(bool isfrag)
 534{
 535	if (isfrag)
 536		return sizeof(__be32);
 537	return 3 * sizeof(__be32);
 538}
 539
 540static ssize_t
 541xs_read_stream_header(struct sock_xprt *transport, struct msghdr *msg,
 542		int flags, size_t want, size_t seek)
 543{
 544	struct kvec kvec = {
 545		.iov_base = &transport->recv.fraghdr,
 546		.iov_len = want,
 547	};
 548	return xs_read_kvec(transport->sock, msg, flags, &kvec, want, seek);
 549}
 550
 551#if defined(CONFIG_SUNRPC_BACKCHANNEL)
 552static ssize_t
 553xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 554{
 555	struct rpc_xprt *xprt = &transport->xprt;
 556	struct rpc_rqst *req;
 557	ssize_t ret;
 558
 559	/* Look up and lock the request corresponding to the given XID */
 560	req = xprt_lookup_bc_request(xprt, transport->recv.xid);
 561	if (!req) {
 562		printk(KERN_WARNING "Callback slot table overflowed\n");
 563		return -ESHUTDOWN;
 564	}
 565	if (transport->recv.copied && !req->rq_private_buf.len)
 566		return -ESHUTDOWN;
 567
 568	ret = xs_read_stream_request(transport, msg, flags, req);
 569	if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 570		xprt_complete_bc_request(req, transport->recv.copied);
 571	else
 572		req->rq_private_buf.len = transport->recv.copied;
 573
 574	return ret;
 575}
 576#else /* CONFIG_SUNRPC_BACKCHANNEL */
 577static ssize_t
 578xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 579{
 580	return -ESHUTDOWN;
 581}
 582#endif /* CONFIG_SUNRPC_BACKCHANNEL */
 583
 584static ssize_t
 585xs_read_stream_reply(struct sock_xprt *transport, struct msghdr *msg, int flags)
 586{
 587	struct rpc_xprt *xprt = &transport->xprt;
 588	struct rpc_rqst *req;
 589	ssize_t ret = 0;
 590
 591	/* Look up and lock the request corresponding to the given XID */
 592	spin_lock(&xprt->queue_lock);
 593	req = xprt_lookup_rqst(xprt, transport->recv.xid);
 594	if (!req || (transport->recv.copied && !req->rq_private_buf.len)) {
 595		msg->msg_flags |= MSG_TRUNC;
 596		goto out;
 597	}
 598	xprt_pin_rqst(req);
 599	spin_unlock(&xprt->queue_lock);
 600
 601	ret = xs_read_stream_request(transport, msg, flags, req);
 602
 603	spin_lock(&xprt->queue_lock);
 604	if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 605		xprt_complete_rqst(req->rq_task, transport->recv.copied);
 606	else
 607		req->rq_private_buf.len = transport->recv.copied;
 608	xprt_unpin_rqst(req);
 609out:
 610	spin_unlock(&xprt->queue_lock);
 611	return ret;
 612}
 613
 614static ssize_t
 615xs_read_stream(struct sock_xprt *transport, int flags)
 616{
 617	struct msghdr msg = { 0 };
 618	size_t want, read = 0;
 619	ssize_t ret = 0;
 620
 621	if (transport->recv.len == 0) {
 622		want = xs_read_stream_headersize(transport->recv.copied != 0);
 623		ret = xs_read_stream_header(transport, &msg, flags, want,
 624				transport->recv.offset);
 625		if (ret <= 0)
 626			goto out_err;
 627		transport->recv.offset = ret;
 628		if (transport->recv.offset != want)
 629			return transport->recv.offset;
 630		transport->recv.len = be32_to_cpu(transport->recv.fraghdr) &
 631			RPC_FRAGMENT_SIZE_MASK;
 632		transport->recv.offset -= sizeof(transport->recv.fraghdr);
 633		read = ret;
 634	}
 635
 636	switch (be32_to_cpu(transport->recv.calldir)) {
 637	default:
 638		msg.msg_flags |= MSG_TRUNC;
 639		break;
 640	case RPC_CALL:
 641		ret = xs_read_stream_call(transport, &msg, flags);
 642		break;
 643	case RPC_REPLY:
 644		ret = xs_read_stream_reply(transport, &msg, flags);
 645	}
 646	if (msg.msg_flags & MSG_TRUNC) {
 647		transport->recv.calldir = cpu_to_be32(-1);
 648		transport->recv.copied = -1;
 649	}
 650	if (ret < 0)
 651		goto out_err;
 652	read += ret;
 653	if (transport->recv.offset < transport->recv.len) {
 654		if (!(msg.msg_flags & MSG_TRUNC))
 655			return read;
 656		msg.msg_flags = 0;
 657		ret = xs_read_discard(transport->sock, &msg, flags,
 658				transport->recv.len - transport->recv.offset);
 659		if (ret <= 0)
 660			goto out_err;
 661		transport->recv.offset += ret;
 662		read += ret;
 663		if (transport->recv.offset != transport->recv.len)
 664			return read;
 665	}
 666	if (xs_read_stream_request_done(transport)) {
 667		trace_xs_stream_read_request(transport);
 668		transport->recv.copied = 0;
 669	}
 670	transport->recv.offset = 0;
 671	transport->recv.len = 0;
 672	return read;
 673out_err:
 674	return ret != 0 ? ret : -ESHUTDOWN;
 675}
 676
 677static __poll_t xs_poll_socket(struct sock_xprt *transport)
 678{
 679	return transport->sock->ops->poll(transport->file, transport->sock,
 680			NULL);
 681}
 682
 683static bool xs_poll_socket_readable(struct sock_xprt *transport)
 684{
 685	__poll_t events = xs_poll_socket(transport);
 686
 687	return (events & (EPOLLIN | EPOLLRDNORM)) && !(events & EPOLLRDHUP);
 688}
 689
 690static void xs_poll_check_readable(struct sock_xprt *transport)
 691{
 692
 693	clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
 694	if (!xs_poll_socket_readable(transport))
 695		return;
 696	if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
 697		queue_work(xprtiod_workqueue, &transport->recv_worker);
 698}
 699
 700static void xs_stream_data_receive(struct sock_xprt *transport)
 701{
 702	size_t read = 0;
 703	ssize_t ret = 0;
 
 
 
 
 
 
 704
 705	mutex_lock(&transport->recv_mutex);
 706	if (transport->sock == NULL)
 707		goto out;
 708	for (;;) {
 709		ret = xs_read_stream(transport, MSG_DONTWAIT);
 710		if (ret < 0)
 
 711			break;
 712		read += ret;
 713		cond_resched();
 
 714	}
 715	if (ret == -ESHUTDOWN)
 716		kernel_sock_shutdown(transport->sock, SHUT_RDWR);
 717	else
 718		xs_poll_check_readable(transport);
 719out:
 720	mutex_unlock(&transport->recv_mutex);
 721	trace_xs_stream_read_data(&transport->xprt, ret, read);
 722}
 723
 724static void xs_stream_data_receive_workfn(struct work_struct *work)
 725{
 726	struct sock_xprt *transport =
 727		container_of(work, struct sock_xprt, recv_worker);
 728	unsigned int pflags = memalloc_nofs_save();
 729
 730	xs_stream_data_receive(transport);
 731	memalloc_nofs_restore(pflags);
 732}
 733
 734static void
 735xs_stream_reset_connect(struct sock_xprt *transport)
 736{
 737	transport->recv.offset = 0;
 738	transport->recv.len = 0;
 739	transport->recv.copied = 0;
 740	transport->xmit.offset = 0;
 741}
 742
 743static void
 744xs_stream_start_connect(struct sock_xprt *transport)
 745{
 746	transport->xprt.stat.connect_count++;
 747	transport->xprt.stat.connect_start = jiffies;
 748}
 749
 750#define XS_SENDMSG_FLAGS	(MSG_DONTWAIT | MSG_NOSIGNAL)
 751
 752static int xs_sendmsg(struct socket *sock, struct msghdr *msg, size_t seek)
 753{
 754	if (seek)
 755		iov_iter_advance(&msg->msg_iter, seek);
 756	return sock_sendmsg(sock, msg);
 757}
 758
 759static int xs_send_kvec(struct socket *sock, struct msghdr *msg, struct kvec *vec, size_t seek)
 760{
 761	iov_iter_kvec(&msg->msg_iter, WRITE, vec, 1, vec->iov_len);
 762	return xs_sendmsg(sock, msg, seek);
 763}
 764
 765static int xs_send_pagedata(struct socket *sock, struct msghdr *msg, struct xdr_buf *xdr, size_t base)
 766{
 767	int err;
 768
 769	err = xdr_alloc_bvec(xdr, GFP_KERNEL);
 770	if (err < 0)
 771		return err;
 772
 773	iov_iter_bvec(&msg->msg_iter, WRITE, xdr->bvec,
 774			xdr_buf_pagecount(xdr),
 775			xdr->page_len + xdr->page_base);
 776	return xs_sendmsg(sock, msg, base + xdr->page_base);
 777}
 778
 779#define xs_record_marker_len() sizeof(rpc_fraghdr)
 780
 781/* Common case:
 782 *  - stream transport
 783 *  - sending from byte 0 of the message
 784 *  - the message is wholly contained in @xdr's head iovec
 785 */
 786static int xs_send_rm_and_kvec(struct socket *sock, struct msghdr *msg,
 787		rpc_fraghdr marker, struct kvec *vec, size_t base)
 788{
 789	struct kvec iov[2] = {
 790		[0] = {
 791			.iov_base	= &marker,
 792			.iov_len	= sizeof(marker)
 793		},
 794		[1] = *vec,
 795	};
 796	size_t len = iov[0].iov_len + iov[1].iov_len;
 797
 798	iov_iter_kvec(&msg->msg_iter, WRITE, iov, 2, len);
 799	return xs_sendmsg(sock, msg, base);
 800}
 801
 802/**
 803 * xs_sendpages - write pages directly to a socket
 804 * @sock: socket to send on
 805 * @addr: UDP only -- address of destination
 806 * @addrlen: UDP only -- length of destination address
 807 * @xdr: buffer containing this request
 808 * @base: starting position in the buffer
 809 * @rm: stream record marker field
 810 * @sent_p: return the total number of bytes successfully queued for sending
 811 *
 812 */
 813static int xs_sendpages(struct socket *sock, struct sockaddr *addr, int addrlen, struct xdr_buf *xdr, unsigned int base, rpc_fraghdr rm, int *sent_p)
 814{
 815	struct msghdr msg = {
 816		.msg_name = addr,
 817		.msg_namelen = addrlen,
 818		.msg_flags = XS_SENDMSG_FLAGS | MSG_MORE,
 819	};
 820	unsigned int rmsize = rm ? sizeof(rm) : 0;
 821	unsigned int remainder = rmsize + xdr->len - base;
 822	unsigned int want;
 823	int err = 0;
 
 824
 825	if (unlikely(!sock))
 826		return -ENOTSOCK;
 827
 828	want = xdr->head[0].iov_len + rmsize;
 829	if (base < want) {
 830		unsigned int len = want - base;
 
 
 
 
 831		remainder -= len;
 832		if (remainder == 0)
 833			msg.msg_flags &= ~MSG_MORE;
 834		if (rmsize)
 835			err = xs_send_rm_and_kvec(sock, &msg, rm,
 836					&xdr->head[0], base);
 837		else
 838			err = xs_send_kvec(sock, &msg, &xdr->head[0], base);
 839		if (remainder == 0 || err != len)
 840			goto out;
 841		*sent_p += err;
 842		base = 0;
 843	} else
 844		base -= want;
 845
 846	if (base < xdr->page_len) {
 847		unsigned int len = xdr->page_len - base;
 848		remainder -= len;
 849		if (remainder == 0)
 850			msg.msg_flags &= ~MSG_MORE;
 851		err = xs_send_pagedata(sock, &msg, xdr, base);
 852		if (remainder == 0 || err != len)
 853			goto out;
 854		*sent_p += err;
 855		base = 0;
 856	} else
 857		base -= xdr->page_len;
 858
 859	if (base >= xdr->tail[0].iov_len)
 860		return 0;
 861	msg.msg_flags &= ~MSG_MORE;
 862	err = xs_send_kvec(sock, &msg, &xdr->tail[0], base);
 863out:
 864	if (err > 0) {
 865		*sent_p += err;
 866		err = 0;
 867	}
 868	return err;
 869}
 870
 
 
 
 
 
 
 
 871/**
 872 * xs_nospace - handle transmit was incomplete
 873 * @req: pointer to RPC request
 874 *
 875 */
 876static int xs_nospace(struct rpc_rqst *req)
 877{
 
 878	struct rpc_xprt *xprt = req->rq_xprt;
 879	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 880	struct sock *sk = transport->inet;
 881	int ret = -EAGAIN;
 882
 883	dprintk("RPC: %5u xmit incomplete (%u left of %u)\n",
 884			req->rq_task->tk_pid,
 885			req->rq_slen - transport->xmit.offset,
 886			req->rq_slen);
 887
 888	/* Protect against races with write_space */
 889	spin_lock(&xprt->transport_lock);
 890
 891	/* Don't race with disconnect */
 892	if (xprt_connected(xprt)) {
 893		/* wait for more buffer space */
 894		sk->sk_write_pending++;
 895		xprt_wait_for_buffer_space(xprt);
 896	} else
 897		ret = -ENOTCONN;
 898
 899	spin_unlock(&xprt->transport_lock);
 900
 901	/* Race breaker in case memory is freed before above code is called */
 902	if (ret == -EAGAIN) {
 903		struct socket_wq *wq;
 904
 905		rcu_read_lock();
 906		wq = rcu_dereference(sk->sk_wq);
 907		set_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags);
 908		rcu_read_unlock();
 909
 910		sk->sk_write_space(sk);
 911	}
 912	return ret;
 913}
 914
 915static void
 916xs_stream_prepare_request(struct rpc_rqst *req)
 917{
 918	xdr_free_bvec(&req->rq_rcv_buf);
 919	req->rq_task->tk_status = xdr_alloc_bvec(&req->rq_rcv_buf, GFP_KERNEL);
 920}
 921
 922/*
 923 * Determine if the previous message in the stream was aborted before it
 924 * could complete transmission.
 925 */
 926static bool
 927xs_send_request_was_aborted(struct sock_xprt *transport, struct rpc_rqst *req)
 928{
 929	return transport->xmit.offset != 0 && req->rq_bytes_sent == 0;
 930}
 931
 932/*
 933 * Return the stream record marker field for a record of length < 2^31-1
 934 */
 935static rpc_fraghdr
 936xs_stream_record_marker(struct xdr_buf *xdr)
 937{
 938	if (!xdr->len)
 939		return 0;
 940	return cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | (u32)xdr->len);
 941}
 942
 943/**
 944 * xs_local_send_request - write an RPC request to an AF_LOCAL socket
 945 * @req: pointer to RPC request
 946 *
 947 * Return values:
 948 *        0:	The request has been sent
 949 *   EAGAIN:	The socket was blocked, please call again later to
 950 *		complete the request
 951 * ENOTCONN:	Caller needs to invoke connect logic then call again
 952 *    other:	Some other error occured, the request was not sent
 953 */
 954static int xs_local_send_request(struct rpc_rqst *req)
 955{
 
 956	struct rpc_xprt *xprt = req->rq_xprt;
 957	struct sock_xprt *transport =
 958				container_of(xprt, struct sock_xprt, xprt);
 959	struct xdr_buf *xdr = &req->rq_snd_buf;
 960	rpc_fraghdr rm = xs_stream_record_marker(xdr);
 961	unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
 962	int status;
 963	int sent = 0;
 964
 965	/* Close the stream if the previous transmission was incomplete */
 966	if (xs_send_request_was_aborted(transport, req)) {
 967		xs_close(xprt);
 968		return -ENOTCONN;
 969	}
 970
 971	xs_pktdump("packet data:",
 972			req->rq_svec->iov_base, req->rq_svec->iov_len);
 973
 974	req->rq_xtime = ktime_get();
 975	status = xs_sendpages(transport->sock, NULL, 0, xdr,
 976			      transport->xmit.offset, rm, &sent);
 977	dprintk("RPC:       %s(%u) = %d\n",
 978			__func__, xdr->len - transport->xmit.offset, status);
 979
 980	if (status == -EAGAIN && sock_writeable(transport->inet))
 981		status = -ENOBUFS;
 982
 983	if (likely(sent > 0) || status == 0) {
 984		transport->xmit.offset += sent;
 985		req->rq_bytes_sent = transport->xmit.offset;
 986		if (likely(req->rq_bytes_sent >= msglen)) {
 987			req->rq_xmit_bytes_sent += transport->xmit.offset;
 988			transport->xmit.offset = 0;
 989			return 0;
 990		}
 991		status = -EAGAIN;
 992	}
 993
 994	switch (status) {
 995	case -ENOBUFS:
 996		break;
 997	case -EAGAIN:
 998		status = xs_nospace(req);
 999		break;
1000	default:
1001		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1002			-status);
1003		/* fall through */
1004	case -EPIPE:
1005		xs_close(xprt);
1006		status = -ENOTCONN;
1007	}
1008
1009	return status;
1010}
1011
1012/**
1013 * xs_udp_send_request - write an RPC request to a UDP socket
1014 * @req: pointer to RPC request
1015 *
1016 * Return values:
1017 *        0:	The request has been sent
1018 *   EAGAIN:	The socket was blocked, please call again later to
1019 *		complete the request
1020 * ENOTCONN:	Caller needs to invoke connect logic then call again
1021 *    other:	Some other error occurred, the request was not sent
1022 */
1023static int xs_udp_send_request(struct rpc_rqst *req)
1024{
 
1025	struct rpc_xprt *xprt = req->rq_xprt;
1026	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1027	struct xdr_buf *xdr = &req->rq_snd_buf;
1028	int sent = 0;
1029	int status;
1030
1031	xs_pktdump("packet data:",
1032				req->rq_svec->iov_base,
1033				req->rq_svec->iov_len);
1034
1035	if (!xprt_bound(xprt))
1036		return -ENOTCONN;
1037
1038	if (!xprt_request_get_cong(xprt, req))
1039		return -EBADSLT;
1040
1041	req->rq_xtime = ktime_get();
1042	status = xs_sendpages(transport->sock, xs_addr(xprt), xprt->addrlen,
1043			      xdr, 0, 0, &sent);
1044
1045	dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
1046			xdr->len, status);
1047
1048	/* firewall is blocking us, don't return -EAGAIN or we end up looping */
1049	if (status == -EPERM)
1050		goto process_status;
1051
1052	if (status == -EAGAIN && sock_writeable(transport->inet))
1053		status = -ENOBUFS;
1054
1055	if (sent > 0 || status == 0) {
1056		req->rq_xmit_bytes_sent += sent;
1057		if (sent >= req->rq_slen)
1058			return 0;
1059		/* Still some bytes left; set up for a retry later. */
1060		status = -EAGAIN;
1061	}
1062
1063process_status:
1064	switch (status) {
1065	case -ENOTSOCK:
1066		status = -ENOTCONN;
1067		/* Should we call xs_close() here? */
1068		break;
1069	case -EAGAIN:
1070		status = xs_nospace(req);
1071		break;
1072	case -ENETUNREACH:
1073	case -ENOBUFS:
1074	case -EPIPE:
1075	case -ECONNREFUSED:
1076	case -EPERM:
1077		/* When the server has died, an ICMP port unreachable message
1078		 * prompts ECONNREFUSED. */
1079		break;
1080	default:
1081		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1082			-status);
1083	}
1084
1085	return status;
1086}
1087
1088/**
1089 * xs_tcp_send_request - write an RPC request to a TCP socket
1090 * @req: pointer to RPC request
1091 *
1092 * Return values:
1093 *        0:	The request has been sent
1094 *   EAGAIN:	The socket was blocked, please call again later to
1095 *		complete the request
1096 * ENOTCONN:	Caller needs to invoke connect logic then call again
1097 *    other:	Some other error occurred, the request was not sent
1098 *
1099 * XXX: In the case of soft timeouts, should we eventually give up
1100 *	if sendmsg is not able to make progress?
1101 */
1102static int xs_tcp_send_request(struct rpc_rqst *req)
1103{
 
1104	struct rpc_xprt *xprt = req->rq_xprt;
1105	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1106	struct xdr_buf *xdr = &req->rq_snd_buf;
1107	rpc_fraghdr rm = xs_stream_record_marker(xdr);
1108	unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
1109	bool vm_wait = false;
1110	int status;
1111	int sent;
1112
1113	/* Close the stream if the previous transmission was incomplete */
1114	if (xs_send_request_was_aborted(transport, req)) {
1115		if (transport->sock != NULL)
1116			kernel_sock_shutdown(transport->sock, SHUT_RDWR);
1117		return -ENOTCONN;
1118	}
1119
1120	xs_pktdump("packet data:",
1121				req->rq_svec->iov_base,
1122				req->rq_svec->iov_len);
1123
1124	if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state))
1125		xs_tcp_set_socket_timeouts(xprt, transport->sock);
 
 
 
1126
1127	/* Continue transmitting the packet/record. We must be careful
1128	 * to cope with writespace callbacks arriving _after_ we have
1129	 * called sendmsg(). */
1130	req->rq_xtime = ktime_get();
1131	while (1) {
1132		sent = 0;
1133		status = xs_sendpages(transport->sock, NULL, 0, xdr,
1134				      transport->xmit.offset, rm, &sent);
1135
1136		dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
1137				xdr->len - transport->xmit.offset, status);
1138
1139		/* If we've sent the entire packet, immediately
1140		 * reset the count of bytes sent. */
1141		transport->xmit.offset += sent;
1142		req->rq_bytes_sent = transport->xmit.offset;
1143		if (likely(req->rq_bytes_sent >= msglen)) {
1144			req->rq_xmit_bytes_sent += transport->xmit.offset;
1145			transport->xmit.offset = 0;
1146			return 0;
1147		}
1148
1149		WARN_ON_ONCE(sent == 0 && status == 0);
1150
1151		if (status == -EAGAIN ) {
1152			/*
1153			 * Return EAGAIN if we're sure we're hitting the
1154			 * socket send buffer limits.
1155			 */
1156			if (test_bit(SOCK_NOSPACE, &transport->sock->flags))
1157				break;
1158			/*
1159			 * Did we hit a memory allocation failure?
1160			 */
1161			if (sent == 0) {
1162				status = -ENOBUFS;
1163				if (vm_wait)
1164					break;
1165				/* Retry, knowing now that we're below the
1166				 * socket send buffer limit
1167				 */
1168				vm_wait = true;
1169			}
1170			continue;
1171		}
1172		if (status < 0)
1173			break;
1174		vm_wait = false;
1175	}
1176
1177	switch (status) {
1178	case -ENOTSOCK:
1179		status = -ENOTCONN;
1180		/* Should we call xs_close() here? */
1181		break;
1182	case -EAGAIN:
1183		status = xs_nospace(req);
1184		break;
1185	case -ECONNRESET:
1186	case -ECONNREFUSED:
1187	case -ENOTCONN:
1188	case -EADDRINUSE:
1189	case -ENOBUFS:
1190	case -EPIPE:
1191		break;
1192	default:
1193		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1194			-status);
1195	}
1196
1197	return status;
1198}
1199
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1200static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1201{
1202	transport->old_data_ready = sk->sk_data_ready;
1203	transport->old_state_change = sk->sk_state_change;
1204	transport->old_write_space = sk->sk_write_space;
1205	transport->old_error_report = sk->sk_error_report;
1206}
1207
1208static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1209{
1210	sk->sk_data_ready = transport->old_data_ready;
1211	sk->sk_state_change = transport->old_state_change;
1212	sk->sk_write_space = transport->old_write_space;
1213	sk->sk_error_report = transport->old_error_report;
1214}
1215
1216static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
1217{
1218	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1219
1220	clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1221	clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state);
1222	clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state);
1223	clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state);
1224}
1225
1226static void xs_run_error_worker(struct sock_xprt *transport, unsigned int nr)
1227{
1228	set_bit(nr, &transport->sock_state);
1229	queue_work(xprtiod_workqueue, &transport->error_worker);
1230}
1231
1232static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
1233{
1234	smp_mb__before_atomic();
1235	clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1236	clear_bit(XPRT_CLOSING, &xprt->state);
1237	xs_sock_reset_state_flags(xprt);
1238	smp_mb__after_atomic();
1239}
1240
 
 
 
 
 
 
 
1241/**
1242 * xs_error_report - callback to handle TCP socket state errors
1243 * @sk: socket
1244 *
1245 * Note: we don't call sock_error() since there may be a rpc_task
1246 * using the socket, and so we don't want to clear sk->sk_err.
1247 */
1248static void xs_error_report(struct sock *sk)
1249{
1250	struct sock_xprt *transport;
1251	struct rpc_xprt *xprt;
 
1252
1253	read_lock_bh(&sk->sk_callback_lock);
1254	if (!(xprt = xprt_from_sock(sk)))
1255		goto out;
1256
1257	transport = container_of(xprt, struct sock_xprt, xprt);
1258	transport->xprt_err = -sk->sk_err;
1259	if (transport->xprt_err == 0)
1260		goto out;
 
 
 
1261	dprintk("RPC:       xs_error_report client %p, error=%d...\n",
1262			xprt, -transport->xprt_err);
1263	trace_rpc_socket_error(xprt, sk->sk_socket, transport->xprt_err);
1264
1265	/* barrier ensures xprt_err is set before XPRT_SOCK_WAKE_ERROR */
1266	smp_mb__before_atomic();
1267	xs_run_error_worker(transport, XPRT_SOCK_WAKE_ERROR);
1268 out:
1269	read_unlock_bh(&sk->sk_callback_lock);
1270}
1271
1272static void xs_reset_transport(struct sock_xprt *transport)
1273{
1274	struct socket *sock = transport->sock;
1275	struct sock *sk = transport->inet;
1276	struct rpc_xprt *xprt = &transport->xprt;
1277	struct file *filp = transport->file;
1278
1279	if (sk == NULL)
1280		return;
1281
1282	if (atomic_read(&transport->xprt.swapper))
1283		sk_clear_memalloc(sk);
1284
1285	kernel_sock_shutdown(sock, SHUT_RDWR);
1286
1287	mutex_lock(&transport->recv_mutex);
1288	write_lock_bh(&sk->sk_callback_lock);
1289	transport->inet = NULL;
1290	transport->sock = NULL;
1291	transport->file = NULL;
1292
1293	sk->sk_user_data = NULL;
1294
1295	xs_restore_old_callbacks(transport, sk);
1296	xprt_clear_connected(xprt);
1297	write_unlock_bh(&sk->sk_callback_lock);
1298	xs_sock_reset_connection_flags(xprt);
1299	/* Reset stream record info */
1300	xs_stream_reset_connect(transport);
1301	mutex_unlock(&transport->recv_mutex);
1302
1303	trace_rpc_socket_close(xprt, sock);
1304	fput(filp);
1305
1306	xprt_disconnect_done(xprt);
1307}
1308
1309/**
1310 * xs_close - close a socket
1311 * @xprt: transport
1312 *
1313 * This is used when all requests are complete; ie, no DRC state remains
1314 * on the server we want to save.
1315 *
1316 * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
1317 * xs_reset_transport() zeroing the socket from underneath a writer.
1318 */
1319static void xs_close(struct rpc_xprt *xprt)
1320{
1321	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1322
1323	dprintk("RPC:       xs_close xprt %p\n", xprt);
1324
1325	xs_reset_transport(transport);
1326	xprt->reestablish_timeout = 0;
 
 
1327}
1328
1329static void xs_inject_disconnect(struct rpc_xprt *xprt)
1330{
1331	dprintk("RPC:       injecting transport disconnect on xprt=%p\n",
1332		xprt);
1333	xprt_disconnect_done(xprt);
1334}
1335
1336static void xs_xprt_free(struct rpc_xprt *xprt)
1337{
1338	xs_free_peer_addresses(xprt);
1339	xprt_free(xprt);
1340}
1341
1342/**
1343 * xs_destroy - prepare to shutdown a transport
1344 * @xprt: doomed transport
1345 *
1346 */
1347static void xs_destroy(struct rpc_xprt *xprt)
1348{
1349	struct sock_xprt *transport = container_of(xprt,
1350			struct sock_xprt, xprt);
1351	dprintk("RPC:       xs_destroy xprt %p\n", xprt);
1352
1353	cancel_delayed_work_sync(&transport->connect_worker);
1354	xs_close(xprt);
1355	cancel_work_sync(&transport->recv_worker);
1356	cancel_work_sync(&transport->error_worker);
1357	xs_xprt_free(xprt);
1358	module_put(THIS_MODULE);
1359}
1360
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1361/**
1362 * xs_udp_data_read_skb - receive callback for UDP sockets
1363 * @xprt: transport
1364 * @sk: socket
1365 * @skb: skbuff
1366 *
1367 */
1368static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
1369		struct sock *sk,
1370		struct sk_buff *skb)
1371{
1372	struct rpc_task *task;
1373	struct rpc_rqst *rovr;
1374	int repsize, copied;
1375	u32 _xid;
1376	__be32 *xp;
1377
1378	repsize = skb->len;
1379	if (repsize < 4) {
1380		dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
1381		return;
1382	}
1383
1384	/* Copy the XID from the skb... */
1385	xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
1386	if (xp == NULL)
1387		return;
1388
1389	/* Look up and lock the request corresponding to the given XID */
1390	spin_lock(&xprt->queue_lock);
1391	rovr = xprt_lookup_rqst(xprt, *xp);
1392	if (!rovr)
1393		goto out_unlock;
1394	xprt_pin_rqst(rovr);
1395	xprt_update_rtt(rovr->rq_task);
1396	spin_unlock(&xprt->queue_lock);
1397	task = rovr->rq_task;
1398
1399	if ((copied = rovr->rq_private_buf.buflen) > repsize)
1400		copied = repsize;
1401
1402	/* Suck it into the iovec, verify checksum if not done by hw. */
1403	if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1404		spin_lock(&xprt->queue_lock);
1405		__UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
1406		goto out_unpin;
1407	}
1408
 
1409
1410	spin_lock(&xprt->transport_lock);
1411	xprt_adjust_cwnd(xprt, task, copied);
1412	spin_unlock(&xprt->transport_lock);
1413	spin_lock(&xprt->queue_lock);
1414	xprt_complete_rqst(task, copied);
1415	__UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
1416out_unpin:
1417	xprt_unpin_rqst(rovr);
1418 out_unlock:
1419	spin_unlock(&xprt->queue_lock);
1420}
1421
1422static void xs_udp_data_receive(struct sock_xprt *transport)
1423{
1424	struct sk_buff *skb;
1425	struct sock *sk;
1426	int err;
1427
1428	mutex_lock(&transport->recv_mutex);
1429	sk = transport->inet;
1430	if (sk == NULL)
1431		goto out;
1432	for (;;) {
1433		skb = skb_recv_udp(sk, 0, 1, &err);
1434		if (skb == NULL)
 
 
 
 
 
1435			break;
1436		xs_udp_data_read_skb(&transport->xprt, sk, skb);
1437		consume_skb(skb);
1438		cond_resched();
1439	}
1440	xs_poll_check_readable(transport);
1441out:
1442	mutex_unlock(&transport->recv_mutex);
1443}
1444
1445static void xs_udp_data_receive_workfn(struct work_struct *work)
1446{
1447	struct sock_xprt *transport =
1448		container_of(work, struct sock_xprt, recv_worker);
1449	unsigned int pflags = memalloc_nofs_save();
1450
1451	xs_udp_data_receive(transport);
1452	memalloc_nofs_restore(pflags);
1453}
1454
1455/**
1456 * xs_data_ready - "data ready" callback for UDP sockets
1457 * @sk: socket with data to read
1458 *
1459 */
1460static void xs_data_ready(struct sock *sk)
1461{
1462	struct rpc_xprt *xprt;
1463
1464	read_lock_bh(&sk->sk_callback_lock);
1465	dprintk("RPC:       xs_data_ready...\n");
1466	xprt = xprt_from_sock(sk);
1467	if (xprt != NULL) {
1468		struct sock_xprt *transport = container_of(xprt,
1469				struct sock_xprt, xprt);
1470		transport->old_data_ready(sk);
1471		/* Any data means we had a useful conversation, so
1472		 * then we don't need to delay the next reconnect
1473		 */
1474		if (xprt->reestablish_timeout)
1475			xprt->reestablish_timeout = 0;
1476		if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1477			queue_work(xprtiod_workqueue, &transport->recv_worker);
1478	}
1479	read_unlock_bh(&sk->sk_callback_lock);
1480}
1481
1482/*
1483 * Helper function to force a TCP close if the server is sending
1484 * junk and/or it has put us in CLOSE_WAIT
1485 */
1486static void xs_tcp_force_close(struct rpc_xprt *xprt)
1487{
1488	xprt_force_disconnect(xprt);
1489}
1490
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1491#if defined(CONFIG_SUNRPC_BACKCHANNEL)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1492static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
1493{
1494	return PAGE_SIZE;
1495}
 
 
 
 
 
 
1496#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1497
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1498/**
1499 * xs_tcp_state_change - callback to handle TCP socket state changes
1500 * @sk: socket whose state has changed
1501 *
1502 */
1503static void xs_tcp_state_change(struct sock *sk)
1504{
1505	struct rpc_xprt *xprt;
1506	struct sock_xprt *transport;
1507
1508	read_lock_bh(&sk->sk_callback_lock);
1509	if (!(xprt = xprt_from_sock(sk)))
1510		goto out;
1511	dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1512	dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1513			sk->sk_state, xprt_connected(xprt),
1514			sock_flag(sk, SOCK_DEAD),
1515			sock_flag(sk, SOCK_ZAPPED),
1516			sk->sk_shutdown);
1517
1518	transport = container_of(xprt, struct sock_xprt, xprt);
1519	trace_rpc_socket_state_change(xprt, sk->sk_socket);
1520	switch (sk->sk_state) {
1521	case TCP_ESTABLISHED:
 
1522		if (!xprt_test_and_set_connected(xprt)) {
 
 
 
 
 
 
 
1523			xprt->connect_cookie++;
1524			clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
1525			xprt_clear_connecting(xprt);
1526
1527			xprt->stat.connect_count++;
1528			xprt->stat.connect_time += (long)jiffies -
1529						   xprt->stat.connect_start;
1530			xs_run_error_worker(transport, XPRT_SOCK_WAKE_PENDING);
1531		}
 
1532		break;
1533	case TCP_FIN_WAIT1:
1534		/* The client initiated a shutdown of the socket */
1535		xprt->connect_cookie++;
1536		xprt->reestablish_timeout = 0;
1537		set_bit(XPRT_CLOSING, &xprt->state);
1538		smp_mb__before_atomic();
1539		clear_bit(XPRT_CONNECTED, &xprt->state);
1540		clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1541		smp_mb__after_atomic();
1542		break;
1543	case TCP_CLOSE_WAIT:
1544		/* The server initiated a shutdown of the socket */
1545		xprt->connect_cookie++;
1546		clear_bit(XPRT_CONNECTED, &xprt->state);
1547		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1548		/* fall through */
1549	case TCP_CLOSING:
1550		/*
1551		 * If the server closed down the connection, make sure that
1552		 * we back off before reconnecting
1553		 */
1554		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1555			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1556		break;
1557	case TCP_LAST_ACK:
1558		set_bit(XPRT_CLOSING, &xprt->state);
1559		smp_mb__before_atomic();
1560		clear_bit(XPRT_CONNECTED, &xprt->state);
1561		smp_mb__after_atomic();
1562		break;
1563	case TCP_CLOSE:
1564		if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
1565					&transport->sock_state))
1566			xprt_clear_connecting(xprt);
1567		clear_bit(XPRT_CLOSING, &xprt->state);
1568		/* Trigger the socket release */
1569		xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1570	}
1571 out:
1572	read_unlock_bh(&sk->sk_callback_lock);
1573}
1574
1575static void xs_write_space(struct sock *sk)
1576{
1577	struct socket_wq *wq;
1578	struct sock_xprt *transport;
1579	struct rpc_xprt *xprt;
1580
1581	if (!sk->sk_socket)
1582		return;
1583	clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1584
1585	if (unlikely(!(xprt = xprt_from_sock(sk))))
1586		return;
1587	transport = container_of(xprt, struct sock_xprt, xprt);
1588	rcu_read_lock();
1589	wq = rcu_dereference(sk->sk_wq);
1590	if (!wq || test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags) == 0)
1591		goto out;
1592
1593	xs_run_error_worker(transport, XPRT_SOCK_WAKE_WRITE);
1594	sk->sk_write_pending--;
1595out:
1596	rcu_read_unlock();
1597}
1598
1599/**
1600 * xs_udp_write_space - callback invoked when socket buffer space
1601 *                             becomes available
1602 * @sk: socket whose state has changed
1603 *
1604 * Called when more output buffer space is available for this socket.
1605 * We try not to wake our writers until they can make "significant"
1606 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1607 * with a bunch of small requests.
1608 */
1609static void xs_udp_write_space(struct sock *sk)
1610{
1611	read_lock_bh(&sk->sk_callback_lock);
1612
1613	/* from net/core/sock.c:sock_def_write_space */
1614	if (sock_writeable(sk))
1615		xs_write_space(sk);
1616
1617	read_unlock_bh(&sk->sk_callback_lock);
1618}
1619
1620/**
1621 * xs_tcp_write_space - callback invoked when socket buffer space
1622 *                             becomes available
1623 * @sk: socket whose state has changed
1624 *
1625 * Called when more output buffer space is available for this socket.
1626 * We try not to wake our writers until they can make "significant"
1627 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1628 * with a bunch of small requests.
1629 */
1630static void xs_tcp_write_space(struct sock *sk)
1631{
1632	read_lock_bh(&sk->sk_callback_lock);
1633
1634	/* from net/core/stream.c:sk_stream_write_space */
1635	if (sk_stream_is_writeable(sk))
1636		xs_write_space(sk);
1637
1638	read_unlock_bh(&sk->sk_callback_lock);
1639}
1640
1641static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1642{
1643	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1644	struct sock *sk = transport->inet;
1645
1646	if (transport->rcvsize) {
1647		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1648		sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1649	}
1650	if (transport->sndsize) {
1651		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1652		sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1653		sk->sk_write_space(sk);
1654	}
1655}
1656
1657/**
1658 * xs_udp_set_buffer_size - set send and receive limits
1659 * @xprt: generic transport
1660 * @sndsize: requested size of send buffer, in bytes
1661 * @rcvsize: requested size of receive buffer, in bytes
1662 *
1663 * Set socket send and receive buffer size limits.
1664 */
1665static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1666{
1667	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1668
1669	transport->sndsize = 0;
1670	if (sndsize)
1671		transport->sndsize = sndsize + 1024;
1672	transport->rcvsize = 0;
1673	if (rcvsize)
1674		transport->rcvsize = rcvsize + 1024;
1675
1676	xs_udp_do_set_buffer_size(xprt);
1677}
1678
1679/**
1680 * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1681 * @xprt: controlling transport
1682 * @task: task that timed out
1683 *
1684 * Adjust the congestion window after a retransmit timeout has occurred.
1685 */
1686static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1687{
1688	spin_lock(&xprt->transport_lock);
1689	xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1690	spin_unlock(&xprt->transport_lock);
1691}
1692
1693static int xs_get_random_port(void)
1694{
1695	unsigned short min = xprt_min_resvport, max = xprt_max_resvport;
1696	unsigned short range;
1697	unsigned short rand;
1698
1699	if (max < min)
1700		return -EADDRINUSE;
1701	range = max - min + 1;
1702	rand = (unsigned short) prandom_u32() % range;
1703	return rand + min;
1704}
1705
1706/**
1707 * xs_set_reuseaddr_port - set the socket's port and address reuse options
1708 * @sock: socket
1709 *
1710 * Note that this function has to be called on all sockets that share the
1711 * same port, and it must be called before binding.
1712 */
1713static void xs_sock_set_reuseport(struct socket *sock)
1714{
1715	int opt = 1;
1716
1717	kernel_setsockopt(sock, SOL_SOCKET, SO_REUSEPORT,
1718			(char *)&opt, sizeof(opt));
1719}
1720
1721static unsigned short xs_sock_getport(struct socket *sock)
1722{
1723	struct sockaddr_storage buf;
 
1724	unsigned short port = 0;
1725
1726	if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0)
1727		goto out;
1728	switch (buf.ss_family) {
1729	case AF_INET6:
1730		port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1731		break;
1732	case AF_INET:
1733		port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1734	}
1735out:
1736	return port;
1737}
1738
1739/**
1740 * xs_set_port - reset the port number in the remote endpoint address
1741 * @xprt: generic transport
1742 * @port: new port number
1743 *
1744 */
1745static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1746{
1747	dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1748
1749	rpc_set_port(xs_addr(xprt), port);
1750	xs_update_peer_port(xprt);
1751}
1752
1753static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1754{
1755	if (transport->srcport == 0)
1756		transport->srcport = xs_sock_getport(sock);
1757}
1758
1759static int xs_get_srcport(struct sock_xprt *transport)
1760{
1761	int port = transport->srcport;
1762
1763	if (port == 0 && transport->xprt.resvport)
1764		port = xs_get_random_port();
1765	return port;
1766}
1767
1768static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1769{
1770	if (transport->srcport != 0)
1771		transport->srcport = 0;
1772	if (!transport->xprt.resvport)
1773		return 0;
1774	if (port <= xprt_min_resvport || port > xprt_max_resvport)
1775		return xprt_max_resvport;
1776	return --port;
1777}
1778static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1779{
1780	struct sockaddr_storage myaddr;
1781	int err, nloop = 0;
1782	int port = xs_get_srcport(transport);
1783	unsigned short last;
1784
1785	/*
1786	 * If we are asking for any ephemeral port (i.e. port == 0 &&
1787	 * transport->xprt.resvport == 0), don't bind.  Let the local
1788	 * port selection happen implicitly when the socket is used
1789	 * (for example at connect time).
1790	 *
1791	 * This ensures that we can continue to establish TCP
1792	 * connections even when all local ephemeral ports are already
1793	 * a part of some TCP connection.  This makes no difference
1794	 * for UDP sockets, but also doens't harm them.
1795	 *
1796	 * If we're asking for any reserved port (i.e. port == 0 &&
1797	 * transport->xprt.resvport == 1) xs_get_srcport above will
1798	 * ensure that port is non-zero and we will bind as needed.
1799	 */
1800	if (port <= 0)
1801		return port;
1802
1803	memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1804	do {
1805		rpc_set_port((struct sockaddr *)&myaddr, port);
1806		err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1807				transport->xprt.addrlen);
1808		if (err == 0) {
1809			transport->srcport = port;
1810			break;
1811		}
1812		last = port;
1813		port = xs_next_srcport(transport, port);
1814		if (port > last)
1815			nloop++;
1816	} while (err == -EADDRINUSE && nloop != 2);
1817
1818	if (myaddr.ss_family == AF_INET)
1819		dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1820				&((struct sockaddr_in *)&myaddr)->sin_addr,
1821				port, err ? "failed" : "ok", err);
1822	else
1823		dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1824				&((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1825				port, err ? "failed" : "ok", err);
1826	return err;
1827}
1828
1829/*
1830 * We don't support autobind on AF_LOCAL sockets
1831 */
1832static void xs_local_rpcbind(struct rpc_task *task)
1833{
1834	xprt_set_bound(task->tk_xprt);
1835}
1836
1837static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1838{
1839}
1840
1841#ifdef CONFIG_DEBUG_LOCK_ALLOC
1842static struct lock_class_key xs_key[2];
1843static struct lock_class_key xs_slock_key[2];
1844
1845static inline void xs_reclassify_socketu(struct socket *sock)
1846{
1847	struct sock *sk = sock->sk;
1848
1849	sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1850		&xs_slock_key[1], "sk_lock-AF_LOCAL-RPC", &xs_key[1]);
1851}
1852
1853static inline void xs_reclassify_socket4(struct socket *sock)
1854{
1855	struct sock *sk = sock->sk;
1856
1857	sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1858		&xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1859}
1860
1861static inline void xs_reclassify_socket6(struct socket *sock)
1862{
1863	struct sock *sk = sock->sk;
1864
1865	sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1866		&xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1867}
1868
1869static inline void xs_reclassify_socket(int family, struct socket *sock)
1870{
1871	if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
1872		return;
1873
1874	switch (family) {
1875	case AF_LOCAL:
1876		xs_reclassify_socketu(sock);
1877		break;
1878	case AF_INET:
1879		xs_reclassify_socket4(sock);
1880		break;
1881	case AF_INET6:
1882		xs_reclassify_socket6(sock);
1883		break;
1884	}
1885}
1886#else
1887static inline void xs_reclassify_socket(int family, struct socket *sock)
1888{
1889}
1890#endif
1891
1892static void xs_dummy_setup_socket(struct work_struct *work)
1893{
1894}
1895
1896static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1897		struct sock_xprt *transport, int family, int type,
1898		int protocol, bool reuseport)
1899{
1900	struct file *filp;
1901	struct socket *sock;
1902	int err;
1903
1904	err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1905	if (err < 0) {
1906		dprintk("RPC:       can't create %d transport socket (%d).\n",
1907				protocol, -err);
1908		goto out;
1909	}
1910	xs_reclassify_socket(family, sock);
1911
1912	if (reuseport)
1913		xs_sock_set_reuseport(sock);
1914
1915	err = xs_bind(transport, sock);
1916	if (err) {
1917		sock_release(sock);
1918		goto out;
1919	}
1920
1921	filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1922	if (IS_ERR(filp))
1923		return ERR_CAST(filp);
1924	transport->file = filp;
1925
1926	return sock;
1927out:
1928	return ERR_PTR(err);
1929}
1930
1931static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1932				      struct socket *sock)
1933{
1934	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1935									xprt);
1936
1937	if (!transport->inet) {
1938		struct sock *sk = sock->sk;
1939
1940		write_lock_bh(&sk->sk_callback_lock);
1941
1942		xs_save_old_callbacks(transport, sk);
1943
1944		sk->sk_user_data = xprt;
1945		sk->sk_data_ready = xs_data_ready;
1946		sk->sk_write_space = xs_udp_write_space;
1947		sock_set_flag(sk, SOCK_FASYNC);
1948		sk->sk_error_report = xs_error_report;
 
1949
1950		xprt_clear_connected(xprt);
1951
1952		/* Reset to new socket */
1953		transport->sock = sock;
1954		transport->inet = sk;
1955
1956		write_unlock_bh(&sk->sk_callback_lock);
1957	}
1958
1959	xs_stream_start_connect(transport);
1960
 
1961	return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1962}
1963
1964/**
1965 * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1966 * @transport: socket transport to connect
1967 */
1968static int xs_local_setup_socket(struct sock_xprt *transport)
1969{
1970	struct rpc_xprt *xprt = &transport->xprt;
1971	struct file *filp;
1972	struct socket *sock;
1973	int status = -EIO;
1974
1975	status = __sock_create(xprt->xprt_net, AF_LOCAL,
1976					SOCK_STREAM, 0, &sock, 1);
1977	if (status < 0) {
1978		dprintk("RPC:       can't create AF_LOCAL "
1979			"transport socket (%d).\n", -status);
1980		goto out;
1981	}
1982	xs_reclassify_socket(AF_LOCAL, sock);
1983
1984	filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1985	if (IS_ERR(filp)) {
1986		status = PTR_ERR(filp);
1987		goto out;
1988	}
1989	transport->file = filp;
1990
1991	dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
1992			xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1993
1994	status = xs_local_finish_connecting(xprt, sock);
1995	trace_rpc_socket_connect(xprt, sock, status);
1996	switch (status) {
1997	case 0:
1998		dprintk("RPC:       xprt %p connected to %s\n",
1999				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2000		xprt->stat.connect_count++;
2001		xprt->stat.connect_time += (long)jiffies -
2002					   xprt->stat.connect_start;
2003		xprt_set_connected(xprt);
2004	case -ENOBUFS:
2005		break;
2006	case -ENOENT:
2007		dprintk("RPC:       xprt %p: socket %s does not exist\n",
2008				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2009		break;
2010	case -ECONNREFUSED:
2011		dprintk("RPC:       xprt %p: connection refused for %s\n",
2012				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2013		break;
2014	default:
2015		printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
2016				__func__, -status,
2017				xprt->address_strings[RPC_DISPLAY_ADDR]);
2018	}
2019
2020out:
2021	xprt_clear_connecting(xprt);
2022	xprt_wake_pending_tasks(xprt, status);
2023	return status;
2024}
2025
2026static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2027{
2028	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2029	int ret;
2030
2031	 if (RPC_IS_ASYNC(task)) {
2032		/*
2033		 * We want the AF_LOCAL connect to be resolved in the
2034		 * filesystem namespace of the process making the rpc
2035		 * call.  Thus we connect synchronously.
2036		 *
2037		 * If we want to support asynchronous AF_LOCAL calls,
2038		 * we'll need to figure out how to pass a namespace to
2039		 * connect.
2040		 */
2041		task->tk_rpc_status = -ENOTCONN;
2042		rpc_exit(task, -ENOTCONN);
2043		return;
2044	}
2045	ret = xs_local_setup_socket(transport);
2046	if (ret && !RPC_IS_SOFTCONN(task))
2047		msleep_interruptible(15000);
2048}
2049
2050#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
2051/*
2052 * Note that this should be called with XPRT_LOCKED held (or when we otherwise
2053 * know that we have exclusive access to the socket), to guard against
2054 * races with xs_reset_transport.
2055 */
2056static void xs_set_memalloc(struct rpc_xprt *xprt)
2057{
2058	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
2059			xprt);
2060
2061	/*
2062	 * If there's no sock, then we have nothing to set. The
2063	 * reconnecting process will get it for us.
2064	 */
2065	if (!transport->inet)
2066		return;
2067	if (atomic_read(&xprt->swapper))
2068		sk_set_memalloc(transport->inet);
2069}
2070
2071/**
2072 * xs_enable_swap - Tag this transport as being used for swap.
2073 * @xprt: transport to tag
2074 *
2075 * Take a reference to this transport on behalf of the rpc_clnt, and
2076 * optionally mark it for swapping if it wasn't already.
2077 */
2078static int
2079xs_enable_swap(struct rpc_xprt *xprt)
2080{
2081	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2082
2083	if (atomic_inc_return(&xprt->swapper) != 1)
2084		return 0;
2085	if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2086		return -ERESTARTSYS;
2087	if (xs->inet)
2088		sk_set_memalloc(xs->inet);
2089	xprt_release_xprt(xprt, NULL);
2090	return 0;
2091}
2092
2093/**
2094 * xs_disable_swap - Untag this transport as being used for swap.
2095 * @xprt: transport to tag
2096 *
2097 * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
2098 * swapper refcount goes to 0, untag the socket as a memalloc socket.
2099 */
2100static void
2101xs_disable_swap(struct rpc_xprt *xprt)
2102{
2103	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2104
2105	if (!atomic_dec_and_test(&xprt->swapper))
2106		return;
2107	if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2108		return;
2109	if (xs->inet)
2110		sk_clear_memalloc(xs->inet);
2111	xprt_release_xprt(xprt, NULL);
2112}
2113#else
2114static void xs_set_memalloc(struct rpc_xprt *xprt)
2115{
2116}
2117
2118static int
2119xs_enable_swap(struct rpc_xprt *xprt)
2120{
2121	return -EINVAL;
2122}
2123
2124static void
2125xs_disable_swap(struct rpc_xprt *xprt)
2126{
2127}
2128#endif
2129
2130static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2131{
2132	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2133
2134	if (!transport->inet) {
2135		struct sock *sk = sock->sk;
2136
2137		write_lock_bh(&sk->sk_callback_lock);
2138
2139		xs_save_old_callbacks(transport, sk);
2140
2141		sk->sk_user_data = xprt;
2142		sk->sk_data_ready = xs_data_ready;
2143		sk->sk_write_space = xs_udp_write_space;
2144		sock_set_flag(sk, SOCK_FASYNC);
 
2145
2146		xprt_set_connected(xprt);
2147
2148		/* Reset to new socket */
2149		transport->sock = sock;
2150		transport->inet = sk;
2151
2152		xs_set_memalloc(xprt);
2153
2154		write_unlock_bh(&sk->sk_callback_lock);
2155	}
2156	xs_udp_do_set_buffer_size(xprt);
2157
2158	xprt->stat.connect_start = jiffies;
2159}
2160
2161static void xs_udp_setup_socket(struct work_struct *work)
2162{
2163	struct sock_xprt *transport =
2164		container_of(work, struct sock_xprt, connect_worker.work);
2165	struct rpc_xprt *xprt = &transport->xprt;
2166	struct socket *sock;
2167	int status = -EIO;
2168
2169	sock = xs_create_sock(xprt, transport,
2170			xs_addr(xprt)->sa_family, SOCK_DGRAM,
2171			IPPROTO_UDP, false);
2172	if (IS_ERR(sock))
2173		goto out;
2174
2175	dprintk("RPC:       worker connecting xprt %p via %s to "
2176				"%s (port %s)\n", xprt,
2177			xprt->address_strings[RPC_DISPLAY_PROTO],
2178			xprt->address_strings[RPC_DISPLAY_ADDR],
2179			xprt->address_strings[RPC_DISPLAY_PORT]);
2180
2181	xs_udp_finish_connecting(xprt, sock);
2182	trace_rpc_socket_connect(xprt, sock, 0);
2183	status = 0;
2184out:
2185	xprt_clear_connecting(xprt);
2186	xprt_unlock_connect(xprt, transport);
 
2187	xprt_wake_pending_tasks(xprt, status);
2188}
2189
2190/**
2191 * xs_tcp_shutdown - gracefully shut down a TCP socket
2192 * @xprt: transport
2193 *
2194 * Initiates a graceful shutdown of the TCP socket by calling the
2195 * equivalent of shutdown(SHUT_RDWR);
2196 */
2197static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2198{
2199	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2200	struct socket *sock = transport->sock;
2201	int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
2202
2203	if (sock == NULL)
2204		return;
2205	switch (skst) {
2206	default:
2207		kernel_sock_shutdown(sock, SHUT_RDWR);
2208		trace_rpc_socket_shutdown(xprt, sock);
2209		break;
2210	case TCP_CLOSE:
2211	case TCP_TIME_WAIT:
2212		xs_reset_transport(transport);
2213	}
2214}
2215
2216static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
2217		struct socket *sock)
2218{
2219	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2220	unsigned int keepidle;
2221	unsigned int keepcnt;
2222	unsigned int opt_on = 1;
2223	unsigned int timeo;
2224
2225	spin_lock(&xprt->transport_lock);
2226	keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
2227	keepcnt = xprt->timeout->to_retries + 1;
2228	timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2229		(xprt->timeout->to_retries + 1);
2230	clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2231	spin_unlock(&xprt->transport_lock);
2232
2233	/* TCP Keepalive options */
2234	kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
2235			(char *)&opt_on, sizeof(opt_on));
2236	kernel_setsockopt(sock, SOL_TCP, TCP_KEEPIDLE,
2237			(char *)&keepidle, sizeof(keepidle));
2238	kernel_setsockopt(sock, SOL_TCP, TCP_KEEPINTVL,
2239			(char *)&keepidle, sizeof(keepidle));
2240	kernel_setsockopt(sock, SOL_TCP, TCP_KEEPCNT,
2241			(char *)&keepcnt, sizeof(keepcnt));
2242
2243	/* TCP user timeout (see RFC5482) */
2244	kernel_setsockopt(sock, SOL_TCP, TCP_USER_TIMEOUT,
2245			(char *)&timeo, sizeof(timeo));
2246}
2247
2248static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
2249		unsigned long connect_timeout,
2250		unsigned long reconnect_timeout)
2251{
2252	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2253	struct rpc_timeout to;
2254	unsigned long initval;
2255
2256	spin_lock(&xprt->transport_lock);
2257	if (reconnect_timeout < xprt->max_reconnect_timeout)
2258		xprt->max_reconnect_timeout = reconnect_timeout;
2259	if (connect_timeout < xprt->connect_timeout) {
2260		memcpy(&to, xprt->timeout, sizeof(to));
2261		initval = DIV_ROUND_UP(connect_timeout, to.to_retries + 1);
2262		/* Arbitrary lower limit */
2263		if (initval <  XS_TCP_INIT_REEST_TO << 1)
2264			initval = XS_TCP_INIT_REEST_TO << 1;
2265		to.to_initval = initval;
2266		to.to_maxval = initval;
2267		memcpy(&transport->tcp_timeout, &to,
2268				sizeof(transport->tcp_timeout));
2269		xprt->timeout = &transport->tcp_timeout;
2270		xprt->connect_timeout = connect_timeout;
2271	}
2272	set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2273	spin_unlock(&xprt->transport_lock);
2274}
2275
2276static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2277{
2278	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2279	int ret = -ENOTCONN;
2280
2281	if (!transport->inet) {
2282		struct sock *sk = sock->sk;
 
 
 
 
2283		unsigned int addr_pref = IPV6_PREFER_SRC_PUBLIC;
2284
 
 
 
 
 
 
 
 
 
 
2285		/* Avoid temporary address, they are bad for long-lived
2286		 * connections such as NFS mounts.
2287		 * RFC4941, section 3.6 suggests that:
2288		 *    Individual applications, which have specific
2289		 *    knowledge about the normal duration of connections,
2290		 *    MAY override this as appropriate.
2291		 */
2292		kernel_setsockopt(sock, SOL_IPV6, IPV6_ADDR_PREFERENCES,
2293				(char *)&addr_pref, sizeof(addr_pref));
2294
2295		xs_tcp_set_socket_timeouts(xprt, sock);
 
 
 
 
2296
2297		write_lock_bh(&sk->sk_callback_lock);
2298
2299		xs_save_old_callbacks(transport, sk);
2300
2301		sk->sk_user_data = xprt;
2302		sk->sk_data_ready = xs_data_ready;
2303		sk->sk_state_change = xs_tcp_state_change;
2304		sk->sk_write_space = xs_tcp_write_space;
2305		sock_set_flag(sk, SOCK_FASYNC);
2306		sk->sk_error_report = xs_error_report;
 
2307
2308		/* socket options */
2309		sock_reset_flag(sk, SOCK_LINGER);
2310		tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
2311
2312		xprt_clear_connected(xprt);
2313
2314		/* Reset to new socket */
2315		transport->sock = sock;
2316		transport->inet = sk;
2317
2318		write_unlock_bh(&sk->sk_callback_lock);
2319	}
2320
2321	if (!xprt_bound(xprt))
2322		goto out;
2323
2324	xs_set_memalloc(xprt);
2325
2326	xs_stream_start_connect(transport);
2327
2328	/* Tell the socket layer to start connecting... */
 
 
2329	set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2330	ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2331	switch (ret) {
2332	case 0:
2333		xs_set_srcport(transport, sock);
2334		/* fall through */
2335	case -EINPROGRESS:
2336		/* SYN_SENT! */
2337		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2338			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2339		break;
2340	case -EADDRNOTAVAIL:
2341		/* Source port number is unavailable. Try a new one! */
2342		transport->srcport = 0;
2343	}
2344out:
2345	return ret;
2346}
2347
2348/**
2349 * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2350 * @work: queued work item
2351 *
2352 * Invoked by a work queue tasklet.
2353 */
2354static void xs_tcp_setup_socket(struct work_struct *work)
2355{
2356	struct sock_xprt *transport =
2357		container_of(work, struct sock_xprt, connect_worker.work);
2358	struct socket *sock = transport->sock;
2359	struct rpc_xprt *xprt = &transport->xprt;
2360	int status = -EIO;
2361
2362	if (!sock) {
2363		sock = xs_create_sock(xprt, transport,
2364				xs_addr(xprt)->sa_family, SOCK_STREAM,
2365				IPPROTO_TCP, true);
2366		if (IS_ERR(sock)) {
2367			status = PTR_ERR(sock);
2368			goto out;
2369		}
2370	}
2371
2372	dprintk("RPC:       worker connecting xprt %p via %s to "
2373				"%s (port %s)\n", xprt,
2374			xprt->address_strings[RPC_DISPLAY_PROTO],
2375			xprt->address_strings[RPC_DISPLAY_ADDR],
2376			xprt->address_strings[RPC_DISPLAY_PORT]);
2377
2378	status = xs_tcp_finish_connecting(xprt, sock);
2379	trace_rpc_socket_connect(xprt, sock, status);
2380	dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2381			xprt, -status, xprt_connected(xprt),
2382			sock->sk->sk_state);
2383	switch (status) {
2384	default:
2385		printk("%s: connect returned unhandled error %d\n",
2386			__func__, status);
2387		/* fall through */
2388	case -EADDRNOTAVAIL:
2389		/* We're probably in TIME_WAIT. Get rid of existing socket,
2390		 * and retry
2391		 */
2392		xs_tcp_force_close(xprt);
2393		break;
2394	case 0:
2395	case -EINPROGRESS:
2396	case -EALREADY:
2397		xprt_unlock_connect(xprt, transport);
2398		return;
2399	case -EINVAL:
2400		/* Happens, for instance, if the user specified a link
2401		 * local IPv6 address without a scope-id.
2402		 */
2403	case -ECONNREFUSED:
2404	case -ECONNRESET:
2405	case -ENETDOWN:
2406	case -ENETUNREACH:
2407	case -EHOSTUNREACH:
2408	case -EADDRINUSE:
2409	case -ENOBUFS:
2410		/*
2411		 * xs_tcp_force_close() wakes tasks with -EIO.
2412		 * We need to wake them first to ensure the
2413		 * correct error code.
2414		 */
2415		xprt_wake_pending_tasks(xprt, status);
2416		xs_tcp_force_close(xprt);
2417		goto out;
2418	}
2419	status = -EAGAIN;
2420out:
2421	xprt_clear_connecting(xprt);
2422	xprt_unlock_connect(xprt, transport);
 
2423	xprt_wake_pending_tasks(xprt, status);
2424}
2425
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2426/**
2427 * xs_connect - connect a socket to a remote endpoint
2428 * @xprt: pointer to transport structure
2429 * @task: address of RPC task that manages state of connect request
2430 *
2431 * TCP: If the remote end dropped the connection, delay reconnecting.
2432 *
2433 * UDP socket connects are synchronous, but we use a work queue anyway
2434 * to guarantee that even unprivileged user processes can set up a
2435 * socket on a privileged port.
2436 *
2437 * If a UDP socket connect fails, the delay behavior here prevents
2438 * retry floods (hard mounts).
2439 */
2440static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2441{
2442	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2443	unsigned long delay = 0;
2444
2445	WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2446
2447	if (transport->sock != NULL) {
2448		dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2449				"seconds\n",
2450				xprt, xprt->reestablish_timeout / HZ);
2451
2452		/* Start by resetting any existing state */
2453		xs_reset_transport(transport);
2454
2455		delay = xprt_reconnect_delay(xprt);
2456		xprt_reconnect_backoff(xprt, XS_TCP_INIT_REEST_TO);
2457
2458	} else
2459		dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2460
2461	queue_delayed_work(xprtiod_workqueue,
2462			&transport->connect_worker,
2463			delay);
2464}
2465
2466static void xs_wake_disconnect(struct sock_xprt *transport)
2467{
2468	if (test_and_clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state))
2469		xs_tcp_force_close(&transport->xprt);
2470}
2471
2472static void xs_wake_write(struct sock_xprt *transport)
2473{
2474	if (test_and_clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state))
2475		xprt_write_space(&transport->xprt);
2476}
2477
2478static void xs_wake_error(struct sock_xprt *transport)
2479{
2480	int sockerr;
2481
2482	if (!test_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2483		return;
2484	mutex_lock(&transport->recv_mutex);
2485	if (transport->sock == NULL)
2486		goto out;
2487	if (!test_and_clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2488		goto out;
2489	sockerr = xchg(&transport->xprt_err, 0);
2490	if (sockerr < 0)
2491		xprt_wake_pending_tasks(&transport->xprt, sockerr);
2492out:
2493	mutex_unlock(&transport->recv_mutex);
2494}
2495
2496static void xs_wake_pending(struct sock_xprt *transport)
2497{
2498	if (test_and_clear_bit(XPRT_SOCK_WAKE_PENDING, &transport->sock_state))
2499		xprt_wake_pending_tasks(&transport->xprt, -EAGAIN);
2500}
2501
2502static void xs_error_handle(struct work_struct *work)
2503{
2504	struct sock_xprt *transport = container_of(work,
2505			struct sock_xprt, error_worker);
2506
2507	xs_wake_disconnect(transport);
2508	xs_wake_write(transport);
2509	xs_wake_error(transport);
2510	xs_wake_pending(transport);
2511}
2512
2513/**
2514 * xs_local_print_stats - display AF_LOCAL socket-specifc stats
2515 * @xprt: rpc_xprt struct containing statistics
2516 * @seq: output file
2517 *
2518 */
2519static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2520{
2521	long idle_time = 0;
2522
2523	if (xprt_connected(xprt))
2524		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2525
2526	seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2527			"%llu %llu %lu %llu %llu\n",
2528			xprt->stat.bind_count,
2529			xprt->stat.connect_count,
2530			xprt->stat.connect_time / HZ,
2531			idle_time,
2532			xprt->stat.sends,
2533			xprt->stat.recvs,
2534			xprt->stat.bad_xids,
2535			xprt->stat.req_u,
2536			xprt->stat.bklog_u,
2537			xprt->stat.max_slots,
2538			xprt->stat.sending_u,
2539			xprt->stat.pending_u);
2540}
2541
2542/**
2543 * xs_udp_print_stats - display UDP socket-specifc stats
2544 * @xprt: rpc_xprt struct containing statistics
2545 * @seq: output file
2546 *
2547 */
2548static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2549{
2550	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2551
2552	seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2553			"%lu %llu %llu\n",
2554			transport->srcport,
2555			xprt->stat.bind_count,
2556			xprt->stat.sends,
2557			xprt->stat.recvs,
2558			xprt->stat.bad_xids,
2559			xprt->stat.req_u,
2560			xprt->stat.bklog_u,
2561			xprt->stat.max_slots,
2562			xprt->stat.sending_u,
2563			xprt->stat.pending_u);
2564}
2565
2566/**
2567 * xs_tcp_print_stats - display TCP socket-specifc stats
2568 * @xprt: rpc_xprt struct containing statistics
2569 * @seq: output file
2570 *
2571 */
2572static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2573{
2574	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2575	long idle_time = 0;
2576
2577	if (xprt_connected(xprt))
2578		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2579
2580	seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2581			"%llu %llu %lu %llu %llu\n",
2582			transport->srcport,
2583			xprt->stat.bind_count,
2584			xprt->stat.connect_count,
2585			xprt->stat.connect_time / HZ,
2586			idle_time,
2587			xprt->stat.sends,
2588			xprt->stat.recvs,
2589			xprt->stat.bad_xids,
2590			xprt->stat.req_u,
2591			xprt->stat.bklog_u,
2592			xprt->stat.max_slots,
2593			xprt->stat.sending_u,
2594			xprt->stat.pending_u);
2595}
2596
2597/*
2598 * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2599 * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2600 * to use the server side send routines.
2601 */
2602static int bc_malloc(struct rpc_task *task)
2603{
2604	struct rpc_rqst *rqst = task->tk_rqstp;
2605	size_t size = rqst->rq_callsize;
2606	struct page *page;
2607	struct rpc_buffer *buf;
2608
2609	if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2610		WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2611			  size);
2612		return -EINVAL;
2613	}
2614
2615	page = alloc_page(GFP_KERNEL);
2616	if (!page)
2617		return -ENOMEM;
2618
2619	buf = page_address(page);
2620	buf->len = PAGE_SIZE;
2621
2622	rqst->rq_buffer = buf->data;
2623	rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2624	return 0;
2625}
2626
2627/*
2628 * Free the space allocated in the bc_alloc routine
2629 */
2630static void bc_free(struct rpc_task *task)
2631{
2632	void *buffer = task->tk_rqstp->rq_buffer;
2633	struct rpc_buffer *buf;
2634
2635	buf = container_of(buffer, struct rpc_buffer, data);
2636	free_page((unsigned long)buf);
2637}
2638
2639/*
2640 * Use the svc_sock to send the callback. Must be called with svsk->sk_mutex
2641 * held. Borrows heavily from svc_tcp_sendto and xs_tcp_send_request.
2642 */
2643static int bc_sendto(struct rpc_rqst *req)
2644{
2645	int len;
2646	struct xdr_buf *xbufp = &req->rq_snd_buf;
 
2647	struct sock_xprt *transport =
2648			container_of(req->rq_xprt, struct sock_xprt, xprt);
 
2649	unsigned long headoff;
2650	unsigned long tailoff;
2651	struct page *tailpage;
2652	struct msghdr msg = {
2653		.msg_flags	= MSG_MORE
2654	};
2655	rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT |
2656					 (u32)xbufp->len);
2657	struct kvec iov = {
2658		.iov_base	= &marker,
2659		.iov_len	= sizeof(marker),
2660	};
2661
2662	len = kernel_sendmsg(transport->sock, &msg, &iov, 1, iov.iov_len);
2663	if (len != iov.iov_len)
2664		return -EAGAIN;
2665
2666	tailpage = NULL;
2667	if (xbufp->tail[0].iov_len)
2668		tailpage = virt_to_page(xbufp->tail[0].iov_base);
2669	tailoff = (unsigned long)xbufp->tail[0].iov_base & ~PAGE_MASK;
2670	headoff = (unsigned long)xbufp->head[0].iov_base & ~PAGE_MASK;
2671	len = svc_send_common(transport->sock, xbufp,
2672			      virt_to_page(xbufp->head[0].iov_base), headoff,
2673			      tailpage, tailoff);
2674	if (len != xbufp->len)
2675		return -EAGAIN;
 
 
 
 
2676	return len;
2677}
2678
2679/*
2680 * The send routine. Borrows from svc_send
2681 */
2682static int bc_send_request(struct rpc_rqst *req)
2683{
 
2684	struct svc_xprt	*xprt;
2685	int len;
2686
2687	dprintk("sending request with xid: %08x\n", ntohl(req->rq_xid));
2688	/*
2689	 * Get the server socket associated with this callback xprt
2690	 */
2691	xprt = req->rq_xprt->bc_xprt;
2692
2693	/*
2694	 * Grab the mutex to serialize data as the connection is shared
2695	 * with the fore channel
2696	 */
2697	mutex_lock(&xprt->xpt_mutex);
 
 
 
 
 
2698	if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2699		len = -ENOTCONN;
2700	else
2701		len = bc_sendto(req);
2702	mutex_unlock(&xprt->xpt_mutex);
2703
2704	if (len > 0)
2705		len = 0;
2706
2707	return len;
2708}
2709
2710/*
2711 * The close routine. Since this is client initiated, we do nothing
2712 */
2713
2714static void bc_close(struct rpc_xprt *xprt)
2715{
2716}
2717
2718/*
2719 * The xprt destroy routine. Again, because this connection is client
2720 * initiated, we do nothing
2721 */
2722
2723static void bc_destroy(struct rpc_xprt *xprt)
2724{
2725	dprintk("RPC:       bc_destroy xprt %p\n", xprt);
2726
2727	xs_xprt_free(xprt);
2728	module_put(THIS_MODULE);
2729}
2730
2731static const struct rpc_xprt_ops xs_local_ops = {
2732	.reserve_xprt		= xprt_reserve_xprt,
2733	.release_xprt		= xprt_release_xprt,
2734	.alloc_slot		= xprt_alloc_slot,
2735	.free_slot		= xprt_free_slot,
2736	.rpcbind		= xs_local_rpcbind,
2737	.set_port		= xs_local_set_port,
2738	.connect		= xs_local_connect,
2739	.buf_alloc		= rpc_malloc,
2740	.buf_free		= rpc_free,
2741	.prepare_request	= xs_stream_prepare_request,
2742	.send_request		= xs_local_send_request,
2743	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
2744	.close			= xs_close,
2745	.destroy		= xs_destroy,
2746	.print_stats		= xs_local_print_stats,
2747	.enable_swap		= xs_enable_swap,
2748	.disable_swap		= xs_disable_swap,
2749};
2750
2751static const struct rpc_xprt_ops xs_udp_ops = {
2752	.set_buffer_size	= xs_udp_set_buffer_size,
2753	.reserve_xprt		= xprt_reserve_xprt_cong,
2754	.release_xprt		= xprt_release_xprt_cong,
2755	.alloc_slot		= xprt_alloc_slot,
2756	.free_slot		= xprt_free_slot,
2757	.rpcbind		= rpcb_getport_async,
2758	.set_port		= xs_set_port,
2759	.connect		= xs_connect,
2760	.buf_alloc		= rpc_malloc,
2761	.buf_free		= rpc_free,
2762	.send_request		= xs_udp_send_request,
2763	.wait_for_reply_request	= xprt_wait_for_reply_request_rtt,
2764	.timer			= xs_udp_timer,
2765	.release_request	= xprt_release_rqst_cong,
2766	.close			= xs_close,
2767	.destroy		= xs_destroy,
2768	.print_stats		= xs_udp_print_stats,
2769	.enable_swap		= xs_enable_swap,
2770	.disable_swap		= xs_disable_swap,
2771	.inject_disconnect	= xs_inject_disconnect,
2772};
2773
2774static const struct rpc_xprt_ops xs_tcp_ops = {
2775	.reserve_xprt		= xprt_reserve_xprt,
2776	.release_xprt		= xprt_release_xprt,
2777	.alloc_slot		= xprt_alloc_slot,
2778	.free_slot		= xprt_free_slot,
2779	.rpcbind		= rpcb_getport_async,
2780	.set_port		= xs_set_port,
2781	.connect		= xs_connect,
2782	.buf_alloc		= rpc_malloc,
2783	.buf_free		= rpc_free,
2784	.prepare_request	= xs_stream_prepare_request,
2785	.send_request		= xs_tcp_send_request,
2786	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
2787	.close			= xs_tcp_shutdown,
2788	.destroy		= xs_destroy,
2789	.set_connect_timeout	= xs_tcp_set_connect_timeout,
2790	.print_stats		= xs_tcp_print_stats,
2791	.enable_swap		= xs_enable_swap,
2792	.disable_swap		= xs_disable_swap,
2793	.inject_disconnect	= xs_inject_disconnect,
2794#ifdef CONFIG_SUNRPC_BACKCHANNEL
2795	.bc_setup		= xprt_setup_bc,
 
2796	.bc_maxpayload		= xs_tcp_bc_maxpayload,
2797	.bc_num_slots		= xprt_bc_max_slots,
2798	.bc_free_rqst		= xprt_free_bc_rqst,
2799	.bc_destroy		= xprt_destroy_bc,
2800#endif
2801};
2802
2803/*
2804 * The rpc_xprt_ops for the server backchannel
2805 */
2806
2807static const struct rpc_xprt_ops bc_tcp_ops = {
2808	.reserve_xprt		= xprt_reserve_xprt,
2809	.release_xprt		= xprt_release_xprt,
2810	.alloc_slot		= xprt_alloc_slot,
2811	.free_slot		= xprt_free_slot,
2812	.buf_alloc		= bc_malloc,
2813	.buf_free		= bc_free,
2814	.send_request		= bc_send_request,
2815	.wait_for_reply_request	= xprt_wait_for_reply_request_def,
2816	.close			= bc_close,
2817	.destroy		= bc_destroy,
2818	.print_stats		= xs_tcp_print_stats,
2819	.enable_swap		= xs_enable_swap,
2820	.disable_swap		= xs_disable_swap,
2821	.inject_disconnect	= xs_inject_disconnect,
2822};
2823
2824static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2825{
2826	static const struct sockaddr_in sin = {
2827		.sin_family		= AF_INET,
2828		.sin_addr.s_addr	= htonl(INADDR_ANY),
2829	};
2830	static const struct sockaddr_in6 sin6 = {
2831		.sin6_family		= AF_INET6,
2832		.sin6_addr		= IN6ADDR_ANY_INIT,
2833	};
2834
2835	switch (family) {
2836	case AF_LOCAL:
2837		break;
2838	case AF_INET:
2839		memcpy(sap, &sin, sizeof(sin));
2840		break;
2841	case AF_INET6:
2842		memcpy(sap, &sin6, sizeof(sin6));
2843		break;
2844	default:
2845		dprintk("RPC:       %s: Bad address family\n", __func__);
2846		return -EAFNOSUPPORT;
2847	}
2848	return 0;
2849}
2850
2851static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2852				      unsigned int slot_table_size,
2853				      unsigned int max_slot_table_size)
2854{
2855	struct rpc_xprt *xprt;
2856	struct sock_xprt *new;
2857
2858	if (args->addrlen > sizeof(xprt->addr)) {
2859		dprintk("RPC:       xs_setup_xprt: address too large\n");
2860		return ERR_PTR(-EBADF);
2861	}
2862
2863	xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2864			max_slot_table_size);
2865	if (xprt == NULL) {
2866		dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2867				"rpc_xprt\n");
2868		return ERR_PTR(-ENOMEM);
2869	}
2870
2871	new = container_of(xprt, struct sock_xprt, xprt);
2872	mutex_init(&new->recv_mutex);
2873	memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2874	xprt->addrlen = args->addrlen;
2875	if (args->srcaddr)
2876		memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2877	else {
2878		int err;
2879		err = xs_init_anyaddr(args->dstaddr->sa_family,
2880					(struct sockaddr *)&new->srcaddr);
2881		if (err != 0) {
2882			xprt_free(xprt);
2883			return ERR_PTR(err);
2884		}
2885	}
2886
2887	return xprt;
2888}
2889
2890static const struct rpc_timeout xs_local_default_timeout = {
2891	.to_initval = 10 * HZ,
2892	.to_maxval = 10 * HZ,
2893	.to_retries = 2,
2894};
2895
2896/**
2897 * xs_setup_local - Set up transport to use an AF_LOCAL socket
2898 * @args: rpc transport creation arguments
2899 *
2900 * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2901 */
2902static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2903{
2904	struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2905	struct sock_xprt *transport;
2906	struct rpc_xprt *xprt;
2907	struct rpc_xprt *ret;
2908
2909	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2910			xprt_max_tcp_slot_table_entries);
2911	if (IS_ERR(xprt))
2912		return xprt;
2913	transport = container_of(xprt, struct sock_xprt, xprt);
2914
2915	xprt->prot = 0;
 
2916	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2917
2918	xprt->bind_timeout = XS_BIND_TO;
2919	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2920	xprt->idle_timeout = XS_IDLE_DISC_TO;
2921
2922	xprt->ops = &xs_local_ops;
2923	xprt->timeout = &xs_local_default_timeout;
2924
2925	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2926	INIT_WORK(&transport->error_worker, xs_error_handle);
2927	INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket);
2928
2929	switch (sun->sun_family) {
2930	case AF_LOCAL:
2931		if (sun->sun_path[0] != '/') {
2932			dprintk("RPC:       bad AF_LOCAL address: %s\n",
2933					sun->sun_path);
2934			ret = ERR_PTR(-EINVAL);
2935			goto out_err;
2936		}
2937		xprt_set_bound(xprt);
2938		xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
2939		ret = ERR_PTR(xs_local_setup_socket(transport));
2940		if (ret)
2941			goto out_err;
2942		break;
2943	default:
2944		ret = ERR_PTR(-EAFNOSUPPORT);
2945		goto out_err;
2946	}
2947
2948	dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
2949			xprt->address_strings[RPC_DISPLAY_ADDR]);
2950
2951	if (try_module_get(THIS_MODULE))
2952		return xprt;
2953	ret = ERR_PTR(-EINVAL);
2954out_err:
2955	xs_xprt_free(xprt);
2956	return ret;
2957}
2958
2959static const struct rpc_timeout xs_udp_default_timeout = {
2960	.to_initval = 5 * HZ,
2961	.to_maxval = 30 * HZ,
2962	.to_increment = 5 * HZ,
2963	.to_retries = 5,
2964};
2965
2966/**
2967 * xs_setup_udp - Set up transport to use a UDP socket
2968 * @args: rpc transport creation arguments
2969 *
2970 */
2971static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2972{
2973	struct sockaddr *addr = args->dstaddr;
2974	struct rpc_xprt *xprt;
2975	struct sock_xprt *transport;
2976	struct rpc_xprt *ret;
2977
2978	xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2979			xprt_udp_slot_table_entries);
2980	if (IS_ERR(xprt))
2981		return xprt;
2982	transport = container_of(xprt, struct sock_xprt, xprt);
2983
2984	xprt->prot = IPPROTO_UDP;
 
2985	/* XXX: header size can vary due to auth type, IPv6, etc. */
2986	xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2987
2988	xprt->bind_timeout = XS_BIND_TO;
2989	xprt->reestablish_timeout = XS_UDP_REEST_TO;
2990	xprt->idle_timeout = XS_IDLE_DISC_TO;
2991
2992	xprt->ops = &xs_udp_ops;
2993
2994	xprt->timeout = &xs_udp_default_timeout;
2995
2996	INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
2997	INIT_WORK(&transport->error_worker, xs_error_handle);
2998	INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
2999
3000	switch (addr->sa_family) {
3001	case AF_INET:
3002		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3003			xprt_set_bound(xprt);
3004
3005		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
3006		break;
3007	case AF_INET6:
3008		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3009			xprt_set_bound(xprt);
3010
3011		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
3012		break;
3013	default:
3014		ret = ERR_PTR(-EAFNOSUPPORT);
3015		goto out_err;
3016	}
3017
3018	if (xprt_bound(xprt))
3019		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3020				xprt->address_strings[RPC_DISPLAY_ADDR],
3021				xprt->address_strings[RPC_DISPLAY_PORT],
3022				xprt->address_strings[RPC_DISPLAY_PROTO]);
3023	else
3024		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3025				xprt->address_strings[RPC_DISPLAY_ADDR],
3026				xprt->address_strings[RPC_DISPLAY_PROTO]);
3027
3028	if (try_module_get(THIS_MODULE))
3029		return xprt;
3030	ret = ERR_PTR(-EINVAL);
3031out_err:
3032	xs_xprt_free(xprt);
3033	return ret;
3034}
3035
3036static const struct rpc_timeout xs_tcp_default_timeout = {
3037	.to_initval = 60 * HZ,
3038	.to_maxval = 60 * HZ,
3039	.to_retries = 2,
3040};
3041
3042/**
3043 * xs_setup_tcp - Set up transport to use a TCP socket
3044 * @args: rpc transport creation arguments
3045 *
3046 */
3047static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
3048{
3049	struct sockaddr *addr = args->dstaddr;
3050	struct rpc_xprt *xprt;
3051	struct sock_xprt *transport;
3052	struct rpc_xprt *ret;
3053	unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
3054
3055	if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
3056		max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
3057
3058	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3059			max_slot_table_size);
3060	if (IS_ERR(xprt))
3061		return xprt;
3062	transport = container_of(xprt, struct sock_xprt, xprt);
3063
3064	xprt->prot = IPPROTO_TCP;
 
3065	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3066
3067	xprt->bind_timeout = XS_BIND_TO;
3068	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
3069	xprt->idle_timeout = XS_IDLE_DISC_TO;
3070
3071	xprt->ops = &xs_tcp_ops;
3072	xprt->timeout = &xs_tcp_default_timeout;
3073
3074	xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
3075	xprt->connect_timeout = xprt->timeout->to_initval *
3076		(xprt->timeout->to_retries + 1);
3077
3078	INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
3079	INIT_WORK(&transport->error_worker, xs_error_handle);
3080	INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
3081
3082	switch (addr->sa_family) {
3083	case AF_INET:
3084		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3085			xprt_set_bound(xprt);
3086
3087		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
3088		break;
3089	case AF_INET6:
3090		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3091			xprt_set_bound(xprt);
3092
3093		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
3094		break;
3095	default:
3096		ret = ERR_PTR(-EAFNOSUPPORT);
3097		goto out_err;
3098	}
3099
3100	if (xprt_bound(xprt))
3101		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3102				xprt->address_strings[RPC_DISPLAY_ADDR],
3103				xprt->address_strings[RPC_DISPLAY_PORT],
3104				xprt->address_strings[RPC_DISPLAY_PROTO]);
3105	else
3106		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3107				xprt->address_strings[RPC_DISPLAY_ADDR],
3108				xprt->address_strings[RPC_DISPLAY_PROTO]);
3109
3110	if (try_module_get(THIS_MODULE))
3111		return xprt;
3112	ret = ERR_PTR(-EINVAL);
3113out_err:
3114	xs_xprt_free(xprt);
3115	return ret;
3116}
3117
3118/**
3119 * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
3120 * @args: rpc transport creation arguments
3121 *
3122 */
3123static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
3124{
3125	struct sockaddr *addr = args->dstaddr;
3126	struct rpc_xprt *xprt;
3127	struct sock_xprt *transport;
3128	struct svc_sock *bc_sock;
3129	struct rpc_xprt *ret;
3130
3131	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3132			xprt_tcp_slot_table_entries);
3133	if (IS_ERR(xprt))
3134		return xprt;
3135	transport = container_of(xprt, struct sock_xprt, xprt);
3136
3137	xprt->prot = IPPROTO_TCP;
 
3138	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3139	xprt->timeout = &xs_tcp_default_timeout;
3140
3141	/* backchannel */
3142	xprt_set_bound(xprt);
3143	xprt->bind_timeout = 0;
3144	xprt->reestablish_timeout = 0;
3145	xprt->idle_timeout = 0;
3146
3147	xprt->ops = &bc_tcp_ops;
3148
3149	switch (addr->sa_family) {
3150	case AF_INET:
3151		xs_format_peer_addresses(xprt, "tcp",
3152					 RPCBIND_NETID_TCP);
3153		break;
3154	case AF_INET6:
3155		xs_format_peer_addresses(xprt, "tcp",
3156				   RPCBIND_NETID_TCP6);
3157		break;
3158	default:
3159		ret = ERR_PTR(-EAFNOSUPPORT);
3160		goto out_err;
3161	}
3162
3163	dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3164			xprt->address_strings[RPC_DISPLAY_ADDR],
3165			xprt->address_strings[RPC_DISPLAY_PORT],
3166			xprt->address_strings[RPC_DISPLAY_PROTO]);
3167
3168	/*
3169	 * Once we've associated a backchannel xprt with a connection,
3170	 * we want to keep it around as long as the connection lasts,
3171	 * in case we need to start using it for a backchannel again;
3172	 * this reference won't be dropped until bc_xprt is destroyed.
3173	 */
3174	xprt_get(xprt);
3175	args->bc_xprt->xpt_bc_xprt = xprt;
3176	xprt->bc_xprt = args->bc_xprt;
3177	bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3178	transport->sock = bc_sock->sk_sock;
3179	transport->inet = bc_sock->sk_sk;
3180
3181	/*
3182	 * Since we don't want connections for the backchannel, we set
3183	 * the xprt status to connected
3184	 */
3185	xprt_set_connected(xprt);
3186
3187	if (try_module_get(THIS_MODULE))
3188		return xprt;
3189
3190	args->bc_xprt->xpt_bc_xprt = NULL;
3191	args->bc_xprt->xpt_bc_xps = NULL;
3192	xprt_put(xprt);
3193	ret = ERR_PTR(-EINVAL);
3194out_err:
3195	xs_xprt_free(xprt);
3196	return ret;
3197}
3198
3199static struct xprt_class	xs_local_transport = {
3200	.list		= LIST_HEAD_INIT(xs_local_transport.list),
3201	.name		= "named UNIX socket",
3202	.owner		= THIS_MODULE,
3203	.ident		= XPRT_TRANSPORT_LOCAL,
3204	.setup		= xs_setup_local,
3205};
3206
3207static struct xprt_class	xs_udp_transport = {
3208	.list		= LIST_HEAD_INIT(xs_udp_transport.list),
3209	.name		= "udp",
3210	.owner		= THIS_MODULE,
3211	.ident		= XPRT_TRANSPORT_UDP,
3212	.setup		= xs_setup_udp,
3213};
3214
3215static struct xprt_class	xs_tcp_transport = {
3216	.list		= LIST_HEAD_INIT(xs_tcp_transport.list),
3217	.name		= "tcp",
3218	.owner		= THIS_MODULE,
3219	.ident		= XPRT_TRANSPORT_TCP,
3220	.setup		= xs_setup_tcp,
3221};
3222
3223static struct xprt_class	xs_bc_tcp_transport = {
3224	.list		= LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3225	.name		= "tcp NFSv4.1 backchannel",
3226	.owner		= THIS_MODULE,
3227	.ident		= XPRT_TRANSPORT_BC_TCP,
3228	.setup		= xs_setup_bc_tcp,
3229};
3230
3231/**
3232 * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3233 *
3234 */
3235int init_socket_xprt(void)
3236{
 
3237	if (!sunrpc_table_header)
3238		sunrpc_table_header = register_sysctl_table(sunrpc_table);
 
3239
3240	xprt_register_transport(&xs_local_transport);
3241	xprt_register_transport(&xs_udp_transport);
3242	xprt_register_transport(&xs_tcp_transport);
3243	xprt_register_transport(&xs_bc_tcp_transport);
3244
3245	return 0;
3246}
3247
3248/**
3249 * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3250 *
3251 */
3252void cleanup_socket_xprt(void)
3253{
 
3254	if (sunrpc_table_header) {
3255		unregister_sysctl_table(sunrpc_table_header);
3256		sunrpc_table_header = NULL;
3257	}
 
3258
3259	xprt_unregister_transport(&xs_local_transport);
3260	xprt_unregister_transport(&xs_udp_transport);
3261	xprt_unregister_transport(&xs_tcp_transport);
3262	xprt_unregister_transport(&xs_bc_tcp_transport);
3263}
3264
3265static int param_set_uint_minmax(const char *val,
3266		const struct kernel_param *kp,
3267		unsigned int min, unsigned int max)
3268{
3269	unsigned int num;
3270	int ret;
3271
3272	if (!val)
3273		return -EINVAL;
3274	ret = kstrtouint(val, 0, &num);
3275	if (ret)
3276		return ret;
3277	if (num < min || num > max)
3278		return -EINVAL;
3279	*((unsigned int *)kp->arg) = num;
3280	return 0;
3281}
3282
3283static int param_set_portnr(const char *val, const struct kernel_param *kp)
3284{
3285	return param_set_uint_minmax(val, kp,
 
3286			RPC_MIN_RESVPORT,
 
 
 
3287			RPC_MAX_RESVPORT);
3288}
3289
3290static const struct kernel_param_ops param_ops_portnr = {
3291	.set = param_set_portnr,
3292	.get = param_get_uint,
3293};
3294
3295#define param_check_portnr(name, p) \
3296	__param_check(name, p, unsigned int);
3297
3298module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3299module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3300
3301static int param_set_slot_table_size(const char *val,
3302				     const struct kernel_param *kp)
3303{
3304	return param_set_uint_minmax(val, kp,
3305			RPC_MIN_SLOT_TABLE,
3306			RPC_MAX_SLOT_TABLE);
3307}
3308
3309static const struct kernel_param_ops param_ops_slot_table_size = {
3310	.set = param_set_slot_table_size,
3311	.get = param_get_uint,
3312};
3313
3314#define param_check_slot_table_size(name, p) \
3315	__param_check(name, p, unsigned int);
3316
3317static int param_set_max_slot_table_size(const char *val,
3318				     const struct kernel_param *kp)
3319{
3320	return param_set_uint_minmax(val, kp,
3321			RPC_MIN_SLOT_TABLE,
3322			RPC_MAX_SLOT_TABLE_LIMIT);
3323}
3324
3325static const struct kernel_param_ops param_ops_max_slot_table_size = {
3326	.set = param_set_max_slot_table_size,
3327	.get = param_get_uint,
3328};
3329
3330#define param_check_max_slot_table_size(name, p) \
3331	__param_check(name, p, unsigned int);
3332
3333module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3334		   slot_table_size, 0644);
3335module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3336		   max_slot_table_size, 0644);
3337module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3338		   slot_table_size, 0644);
v4.10.11
 
   1/*
   2 * linux/net/sunrpc/xprtsock.c
   3 *
   4 * Client-side transport implementation for sockets.
   5 *
   6 * TCP callback races fixes (C) 1998 Red Hat
   7 * TCP send fixes (C) 1998 Red Hat
   8 * TCP NFS related read + write fixes
   9 *  (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
  10 *
  11 * Rewrite of larges part of the code in order to stabilize TCP stuff.
  12 * Fix behaviour when socket buffer is full.
  13 *  (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no>
  14 *
  15 * IP socket transport implementation, (C) 2005 Chuck Lever <cel@netapp.com>
  16 *
  17 * IPv6 support contributed by Gilles Quillard, Bull Open Source, 2005.
  18 *   <gilles.quillard@bull.net>
  19 */
  20
  21#include <linux/types.h>
  22#include <linux/string.h>
  23#include <linux/slab.h>
  24#include <linux/module.h>
  25#include <linux/capability.h>
  26#include <linux/pagemap.h>
  27#include <linux/errno.h>
  28#include <linux/socket.h>
  29#include <linux/in.h>
  30#include <linux/net.h>
  31#include <linux/mm.h>
  32#include <linux/un.h>
  33#include <linux/udp.h>
  34#include <linux/tcp.h>
  35#include <linux/sunrpc/clnt.h>
  36#include <linux/sunrpc/addr.h>
  37#include <linux/sunrpc/sched.h>
  38#include <linux/sunrpc/svcsock.h>
  39#include <linux/sunrpc/xprtsock.h>
  40#include <linux/file.h>
  41#ifdef CONFIG_SUNRPC_BACKCHANNEL
  42#include <linux/sunrpc/bc_xprt.h>
  43#endif
  44
  45#include <net/sock.h>
  46#include <net/checksum.h>
  47#include <net/udp.h>
  48#include <net/tcp.h>
 
 
 
 
  49
  50#include <trace/events/sunrpc.h>
  51
  52#include "sunrpc.h"
  53
  54static void xs_close(struct rpc_xprt *xprt);
 
 
  55
  56/*
  57 * xprtsock tunables
  58 */
  59static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  60static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
  61static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
  62
  63static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
  64static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
  65
  66#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
  67
  68#define XS_TCP_LINGER_TO	(15U * HZ)
  69static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
  70
  71/*
  72 * We can register our own files under /proc/sys/sunrpc by
  73 * calling register_sysctl_table() again.  The files in that
  74 * directory become the union of all files registered there.
  75 *
  76 * We simply need to make sure that we don't collide with
  77 * someone else's file names!
  78 */
  79
  80static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
  81static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
  82static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
  83static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
  84static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
  85
  86static struct ctl_table_header *sunrpc_table_header;
  87
  88/*
  89 * FIXME: changing the UDP slot table size should also resize the UDP
  90 *        socket buffers for existing UDP transports
  91 */
  92static struct ctl_table xs_tunables_table[] = {
  93	{
  94		.procname	= "udp_slot_table_entries",
  95		.data		= &xprt_udp_slot_table_entries,
  96		.maxlen		= sizeof(unsigned int),
  97		.mode		= 0644,
  98		.proc_handler	= proc_dointvec_minmax,
  99		.extra1		= &min_slot_table_size,
 100		.extra2		= &max_slot_table_size
 101	},
 102	{
 103		.procname	= "tcp_slot_table_entries",
 104		.data		= &xprt_tcp_slot_table_entries,
 105		.maxlen		= sizeof(unsigned int),
 106		.mode		= 0644,
 107		.proc_handler	= proc_dointvec_minmax,
 108		.extra1		= &min_slot_table_size,
 109		.extra2		= &max_slot_table_size
 110	},
 111	{
 112		.procname	= "tcp_max_slot_table_entries",
 113		.data		= &xprt_max_tcp_slot_table_entries,
 114		.maxlen		= sizeof(unsigned int),
 115		.mode		= 0644,
 116		.proc_handler	= proc_dointvec_minmax,
 117		.extra1		= &min_slot_table_size,
 118		.extra2		= &max_tcp_slot_table_limit
 119	},
 120	{
 121		.procname	= "min_resvport",
 122		.data		= &xprt_min_resvport,
 123		.maxlen		= sizeof(unsigned int),
 124		.mode		= 0644,
 125		.proc_handler	= proc_dointvec_minmax,
 126		.extra1		= &xprt_min_resvport_limit,
 127		.extra2		= &xprt_max_resvport
 128	},
 129	{
 130		.procname	= "max_resvport",
 131		.data		= &xprt_max_resvport,
 132		.maxlen		= sizeof(unsigned int),
 133		.mode		= 0644,
 134		.proc_handler	= proc_dointvec_minmax,
 135		.extra1		= &xprt_min_resvport,
 136		.extra2		= &xprt_max_resvport_limit
 137	},
 138	{
 139		.procname	= "tcp_fin_timeout",
 140		.data		= &xs_tcp_fin_timeout,
 141		.maxlen		= sizeof(xs_tcp_fin_timeout),
 142		.mode		= 0644,
 143		.proc_handler	= proc_dointvec_jiffies,
 144	},
 145	{ },
 146};
 147
 148static struct ctl_table sunrpc_table[] = {
 149	{
 150		.procname	= "sunrpc",
 151		.mode		= 0555,
 152		.child		= xs_tunables_table
 153	},
 154	{ },
 155};
 156
 157#endif
 158
 159/*
 160 * Wait duration for a reply from the RPC portmapper.
 161 */
 162#define XS_BIND_TO		(60U * HZ)
 163
 164/*
 165 * Delay if a UDP socket connect error occurs.  This is most likely some
 166 * kind of resource problem on the local host.
 167 */
 168#define XS_UDP_REEST_TO		(2U * HZ)
 169
 170/*
 171 * The reestablish timeout allows clients to delay for a bit before attempting
 172 * to reconnect to a server that just dropped our connection.
 173 *
 174 * We implement an exponential backoff when trying to reestablish a TCP
 175 * transport connection with the server.  Some servers like to drop a TCP
 176 * connection when they are overworked, so we start with a short timeout and
 177 * increase over time if the server is down or not responding.
 178 */
 179#define XS_TCP_INIT_REEST_TO	(3U * HZ)
 180
 181/*
 182 * TCP idle timeout; client drops the transport socket if it is idle
 183 * for this long.  Note that we also timeout UDP sockets to prevent
 184 * holding port numbers when there is no RPC traffic.
 185 */
 186#define XS_IDLE_DISC_TO		(5U * 60 * HZ)
 187
 188#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 189# undef  RPC_DEBUG_DATA
 190# define RPCDBG_FACILITY	RPCDBG_TRANS
 191#endif
 192
 193#ifdef RPC_DEBUG_DATA
 194static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 195{
 196	u8 *buf = (u8 *) packet;
 197	int j;
 198
 199	dprintk("RPC:       %s\n", msg);
 200	for (j = 0; j < count && j < 128; j += 4) {
 201		if (!(j & 31)) {
 202			if (j)
 203				dprintk("\n");
 204			dprintk("0x%04x ", j);
 205		}
 206		dprintk("%02x%02x%02x%02x ",
 207			buf[j], buf[j+1], buf[j+2], buf[j+3]);
 208	}
 209	dprintk("\n");
 210}
 211#else
 212static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 213{
 214	/* NOP */
 215}
 216#endif
 217
 218static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
 219{
 220	return (struct rpc_xprt *) sk->sk_user_data;
 221}
 222
 223static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
 224{
 225	return (struct sockaddr *) &xprt->addr;
 226}
 227
 228static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
 229{
 230	return (struct sockaddr_un *) &xprt->addr;
 231}
 232
 233static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
 234{
 235	return (struct sockaddr_in *) &xprt->addr;
 236}
 237
 238static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
 239{
 240	return (struct sockaddr_in6 *) &xprt->addr;
 241}
 242
 243static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
 244{
 245	struct sockaddr *sap = xs_addr(xprt);
 246	struct sockaddr_in6 *sin6;
 247	struct sockaddr_in *sin;
 248	struct sockaddr_un *sun;
 249	char buf[128];
 250
 251	switch (sap->sa_family) {
 252	case AF_LOCAL:
 253		sun = xs_addr_un(xprt);
 254		strlcpy(buf, sun->sun_path, sizeof(buf));
 255		xprt->address_strings[RPC_DISPLAY_ADDR] =
 256						kstrdup(buf, GFP_KERNEL);
 257		break;
 258	case AF_INET:
 259		(void)rpc_ntop(sap, buf, sizeof(buf));
 260		xprt->address_strings[RPC_DISPLAY_ADDR] =
 261						kstrdup(buf, GFP_KERNEL);
 262		sin = xs_addr_in(xprt);
 263		snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
 264		break;
 265	case AF_INET6:
 266		(void)rpc_ntop(sap, buf, sizeof(buf));
 267		xprt->address_strings[RPC_DISPLAY_ADDR] =
 268						kstrdup(buf, GFP_KERNEL);
 269		sin6 = xs_addr_in6(xprt);
 270		snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
 271		break;
 272	default:
 273		BUG();
 274	}
 275
 276	xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
 277}
 278
 279static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
 280{
 281	struct sockaddr *sap = xs_addr(xprt);
 282	char buf[128];
 283
 284	snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
 285	xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
 286
 287	snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
 288	xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
 289}
 290
 291static void xs_format_peer_addresses(struct rpc_xprt *xprt,
 292				     const char *protocol,
 293				     const char *netid)
 294{
 295	xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
 296	xprt->address_strings[RPC_DISPLAY_NETID] = netid;
 297	xs_format_common_peer_addresses(xprt);
 298	xs_format_common_peer_ports(xprt);
 299}
 300
 301static void xs_update_peer_port(struct rpc_xprt *xprt)
 302{
 303	kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
 304	kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
 305
 306	xs_format_common_peer_ports(xprt);
 307}
 308
 309static void xs_free_peer_addresses(struct rpc_xprt *xprt)
 310{
 311	unsigned int i;
 312
 313	for (i = 0; i < RPC_DISPLAY_MAX; i++)
 314		switch (i) {
 315		case RPC_DISPLAY_PROTO:
 316		case RPC_DISPLAY_NETID:
 317			continue;
 318		default:
 319			kfree(xprt->address_strings[i]);
 320		}
 321}
 322
 323#define XS_SENDMSG_FLAGS	(MSG_DONTWAIT | MSG_NOSIGNAL)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 324
 325static int xs_send_kvec(struct socket *sock, struct sockaddr *addr, int addrlen, struct kvec *vec, unsigned int base, int more)
 
 
 326{
 327	struct msghdr msg = {
 328		.msg_name	= addr,
 329		.msg_namelen	= addrlen,
 330		.msg_flags	= XS_SENDMSG_FLAGS | (more ? MSG_MORE : 0),
 331	};
 332	struct kvec iov = {
 333		.iov_base	= vec->iov_base + base,
 334		.iov_len	= vec->iov_len - base,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 335	};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 336
 337	if (iov.iov_len != 0)
 338		return kernel_sendmsg(sock, &msg, &iov, 1, iov.iov_len);
 339	return kernel_sendmsg(sock, &msg, NULL, 0, 0);
 
 
 
 
 
 
 
 
 
 
 340}
 
 341
 342static int xs_send_pagedata(struct socket *sock, struct xdr_buf *xdr, unsigned int base, int more, bool zerocopy, int *sent_p)
 
 343{
 344	ssize_t (*do_sendpage)(struct socket *sock, struct page *page,
 345			int offset, size_t size, int flags);
 346	struct page **ppage;
 347	unsigned int remainder;
 348	int err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 349
 350	remainder = xdr->page_len - base;
 351	base += xdr->page_base;
 352	ppage = xdr->pages + (base >> PAGE_SHIFT);
 353	base &= ~PAGE_MASK;
 354	do_sendpage = sock->ops->sendpage;
 355	if (!zerocopy)
 356		do_sendpage = sock_no_sendpage;
 357	for(;;) {
 358		unsigned int len = min_t(unsigned int, PAGE_SIZE - base, remainder);
 359		int flags = XS_SENDMSG_FLAGS;
 360
 361		remainder -= len;
 362		if (more)
 363			flags |= MSG_MORE;
 364		if (remainder != 0)
 365			flags |= MSG_SENDPAGE_NOTLAST | MSG_MORE;
 366		err = do_sendpage(sock, *ppage, base, len, flags);
 367		if (remainder == 0 || err != len)
 368			break;
 369		*sent_p += err;
 370		ppage++;
 371		base = 0;
 372	}
 373	if (err > 0) {
 374		*sent_p += err;
 375		err = 0;
 376	}
 377	return err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 378}
 379
 380/**
 381 * xs_sendpages - write pages directly to a socket
 382 * @sock: socket to send on
 383 * @addr: UDP only -- address of destination
 384 * @addrlen: UDP only -- length of destination address
 385 * @xdr: buffer containing this request
 386 * @base: starting position in the buffer
 387 * @zerocopy: true if it is safe to use sendpage()
 388 * @sent_p: return the total number of bytes successfully queued for sending
 389 *
 390 */
 391static int xs_sendpages(struct socket *sock, struct sockaddr *addr, int addrlen, struct xdr_buf *xdr, unsigned int base, bool zerocopy, int *sent_p)
 392{
 393	unsigned int remainder = xdr->len - base;
 
 
 
 
 
 
 
 394	int err = 0;
 395	int sent = 0;
 396
 397	if (unlikely(!sock))
 398		return -ENOTSOCK;
 399
 400	if (base != 0) {
 401		addr = NULL;
 402		addrlen = 0;
 403	}
 404
 405	if (base < xdr->head[0].iov_len || addr != NULL) {
 406		unsigned int len = xdr->head[0].iov_len - base;
 407		remainder -= len;
 408		err = xs_send_kvec(sock, addr, addrlen, &xdr->head[0], base, remainder != 0);
 
 
 
 
 
 
 409		if (remainder == 0 || err != len)
 410			goto out;
 411		*sent_p += err;
 412		base = 0;
 413	} else
 414		base -= xdr->head[0].iov_len;
 415
 416	if (base < xdr->page_len) {
 417		unsigned int len = xdr->page_len - base;
 418		remainder -= len;
 419		err = xs_send_pagedata(sock, xdr, base, remainder != 0, zerocopy, &sent);
 420		*sent_p += sent;
 421		if (remainder == 0 || sent != len)
 
 422			goto out;
 
 423		base = 0;
 424	} else
 425		base -= xdr->page_len;
 426
 427	if (base >= xdr->tail[0].iov_len)
 428		return 0;
 429	err = xs_send_kvec(sock, NULL, 0, &xdr->tail[0], base, 0);
 
 430out:
 431	if (err > 0) {
 432		*sent_p += err;
 433		err = 0;
 434	}
 435	return err;
 436}
 437
 438static void xs_nospace_callback(struct rpc_task *task)
 439{
 440	struct sock_xprt *transport = container_of(task->tk_rqstp->rq_xprt, struct sock_xprt, xprt);
 441
 442	transport->inet->sk_write_pending--;
 443}
 444
 445/**
 446 * xs_nospace - place task on wait queue if transmit was incomplete
 447 * @task: task to put to sleep
 448 *
 449 */
 450static int xs_nospace(struct rpc_task *task)
 451{
 452	struct rpc_rqst *req = task->tk_rqstp;
 453	struct rpc_xprt *xprt = req->rq_xprt;
 454	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 455	struct sock *sk = transport->inet;
 456	int ret = -EAGAIN;
 457
 458	dprintk("RPC: %5u xmit incomplete (%u left of %u)\n",
 459			task->tk_pid, req->rq_slen - req->rq_bytes_sent,
 
 460			req->rq_slen);
 461
 462	/* Protect against races with write_space */
 463	spin_lock_bh(&xprt->transport_lock);
 464
 465	/* Don't race with disconnect */
 466	if (xprt_connected(xprt)) {
 467		/* wait for more buffer space */
 468		sk->sk_write_pending++;
 469		xprt_wait_for_buffer_space(task, xs_nospace_callback);
 470	} else
 471		ret = -ENOTCONN;
 472
 473	spin_unlock_bh(&xprt->transport_lock);
 474
 475	/* Race breaker in case memory is freed before above code is called */
 476	if (ret == -EAGAIN) {
 477		struct socket_wq *wq;
 478
 479		rcu_read_lock();
 480		wq = rcu_dereference(sk->sk_wq);
 481		set_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags);
 482		rcu_read_unlock();
 483
 484		sk->sk_write_space(sk);
 485	}
 486	return ret;
 487}
 488
 
 
 
 
 
 
 
 489/*
 490 * Construct a stream transport record marker in @buf.
 
 491 */
 492static inline void xs_encode_stream_record_marker(struct xdr_buf *buf)
 
 493{
 494	u32 reclen = buf->len - sizeof(rpc_fraghdr);
 495	rpc_fraghdr *base = buf->head[0].iov_base;
 496	*base = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | reclen);
 
 
 
 
 
 
 
 
 
 497}
 498
 499/**
 500 * xs_local_send_request - write an RPC request to an AF_LOCAL socket
 501 * @task: RPC task that manages the state of an RPC request
 502 *
 503 * Return values:
 504 *        0:	The request has been sent
 505 *   EAGAIN:	The socket was blocked, please call again later to
 506 *		complete the request
 507 * ENOTCONN:	Caller needs to invoke connect logic then call again
 508 *    other:	Some other error occured, the request was not sent
 509 */
 510static int xs_local_send_request(struct rpc_task *task)
 511{
 512	struct rpc_rqst *req = task->tk_rqstp;
 513	struct rpc_xprt *xprt = req->rq_xprt;
 514	struct sock_xprt *transport =
 515				container_of(xprt, struct sock_xprt, xprt);
 516	struct xdr_buf *xdr = &req->rq_snd_buf;
 
 
 517	int status;
 518	int sent = 0;
 519
 520	xs_encode_stream_record_marker(&req->rq_snd_buf);
 
 
 
 
 521
 522	xs_pktdump("packet data:",
 523			req->rq_svec->iov_base, req->rq_svec->iov_len);
 524
 525	status = xs_sendpages(transport->sock, NULL, 0, xdr, req->rq_bytes_sent,
 526			      true, &sent);
 
 527	dprintk("RPC:       %s(%u) = %d\n",
 528			__func__, xdr->len - req->rq_bytes_sent, status);
 529
 530	if (status == -EAGAIN && sock_writeable(transport->inet))
 531		status = -ENOBUFS;
 532
 533	if (likely(sent > 0) || status == 0) {
 534		req->rq_bytes_sent += sent;
 535		req->rq_xmit_bytes_sent += sent;
 536		if (likely(req->rq_bytes_sent >= req->rq_slen)) {
 537			req->rq_bytes_sent = 0;
 
 538			return 0;
 539		}
 540		status = -EAGAIN;
 541	}
 542
 543	switch (status) {
 544	case -ENOBUFS:
 545		break;
 546	case -EAGAIN:
 547		status = xs_nospace(task);
 548		break;
 549	default:
 550		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 551			-status);
 
 552	case -EPIPE:
 553		xs_close(xprt);
 554		status = -ENOTCONN;
 555	}
 556
 557	return status;
 558}
 559
 560/**
 561 * xs_udp_send_request - write an RPC request to a UDP socket
 562 * @task: address of RPC task that manages the state of an RPC request
 563 *
 564 * Return values:
 565 *        0:	The request has been sent
 566 *   EAGAIN:	The socket was blocked, please call again later to
 567 *		complete the request
 568 * ENOTCONN:	Caller needs to invoke connect logic then call again
 569 *    other:	Some other error occurred, the request was not sent
 570 */
 571static int xs_udp_send_request(struct rpc_task *task)
 572{
 573	struct rpc_rqst *req = task->tk_rqstp;
 574	struct rpc_xprt *xprt = req->rq_xprt;
 575	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 576	struct xdr_buf *xdr = &req->rq_snd_buf;
 577	int sent = 0;
 578	int status;
 579
 580	xs_pktdump("packet data:",
 581				req->rq_svec->iov_base,
 582				req->rq_svec->iov_len);
 583
 584	if (!xprt_bound(xprt))
 585		return -ENOTCONN;
 
 
 
 
 
 586	status = xs_sendpages(transport->sock, xs_addr(xprt), xprt->addrlen,
 587			      xdr, req->rq_bytes_sent, true, &sent);
 588
 589	dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
 590			xdr->len - req->rq_bytes_sent, status);
 591
 592	/* firewall is blocking us, don't return -EAGAIN or we end up looping */
 593	if (status == -EPERM)
 594		goto process_status;
 595
 596	if (status == -EAGAIN && sock_writeable(transport->inet))
 597		status = -ENOBUFS;
 598
 599	if (sent > 0 || status == 0) {
 600		req->rq_xmit_bytes_sent += sent;
 601		if (sent >= req->rq_slen)
 602			return 0;
 603		/* Still some bytes left; set up for a retry later. */
 604		status = -EAGAIN;
 605	}
 606
 607process_status:
 608	switch (status) {
 609	case -ENOTSOCK:
 610		status = -ENOTCONN;
 611		/* Should we call xs_close() here? */
 612		break;
 613	case -EAGAIN:
 614		status = xs_nospace(task);
 615		break;
 616	case -ENETUNREACH:
 617	case -ENOBUFS:
 618	case -EPIPE:
 619	case -ECONNREFUSED:
 620	case -EPERM:
 621		/* When the server has died, an ICMP port unreachable message
 622		 * prompts ECONNREFUSED. */
 623		break;
 624	default:
 625		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 626			-status);
 627	}
 628
 629	return status;
 630}
 631
 632/**
 633 * xs_tcp_send_request - write an RPC request to a TCP socket
 634 * @task: address of RPC task that manages the state of an RPC request
 635 *
 636 * Return values:
 637 *        0:	The request has been sent
 638 *   EAGAIN:	The socket was blocked, please call again later to
 639 *		complete the request
 640 * ENOTCONN:	Caller needs to invoke connect logic then call again
 641 *    other:	Some other error occurred, the request was not sent
 642 *
 643 * XXX: In the case of soft timeouts, should we eventually give up
 644 *	if sendmsg is not able to make progress?
 645 */
 646static int xs_tcp_send_request(struct rpc_task *task)
 647{
 648	struct rpc_rqst *req = task->tk_rqstp;
 649	struct rpc_xprt *xprt = req->rq_xprt;
 650	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 651	struct xdr_buf *xdr = &req->rq_snd_buf;
 652	bool zerocopy = true;
 
 653	bool vm_wait = false;
 654	int status;
 655	int sent;
 656
 657	xs_encode_stream_record_marker(&req->rq_snd_buf);
 
 
 
 
 
 658
 659	xs_pktdump("packet data:",
 660				req->rq_svec->iov_base,
 661				req->rq_svec->iov_len);
 662	/* Don't use zero copy if this is a resend. If the RPC call
 663	 * completes while the socket holds a reference to the pages,
 664	 * then we may end up resending corrupted data.
 665	 */
 666	if (task->tk_flags & RPC_TASK_SENT)
 667		zerocopy = false;
 668
 669	/* Continue transmitting the packet/record. We must be careful
 670	 * to cope with writespace callbacks arriving _after_ we have
 671	 * called sendmsg(). */
 
 672	while (1) {
 673		sent = 0;
 674		status = xs_sendpages(transport->sock, NULL, 0, xdr,
 675				      req->rq_bytes_sent, zerocopy, &sent);
 676
 677		dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
 678				xdr->len - req->rq_bytes_sent, status);
 679
 680		/* If we've sent the entire packet, immediately
 681		 * reset the count of bytes sent. */
 682		req->rq_bytes_sent += sent;
 683		req->rq_xmit_bytes_sent += sent;
 684		if (likely(req->rq_bytes_sent >= req->rq_slen)) {
 685			req->rq_bytes_sent = 0;
 
 686			return 0;
 687		}
 688
 689		WARN_ON_ONCE(sent == 0 && status == 0);
 690
 691		if (status == -EAGAIN ) {
 692			/*
 693			 * Return EAGAIN if we're sure we're hitting the
 694			 * socket send buffer limits.
 695			 */
 696			if (test_bit(SOCK_NOSPACE, &transport->sock->flags))
 697				break;
 698			/*
 699			 * Did we hit a memory allocation failure?
 700			 */
 701			if (sent == 0) {
 702				status = -ENOBUFS;
 703				if (vm_wait)
 704					break;
 705				/* Retry, knowing now that we're below the
 706				 * socket send buffer limit
 707				 */
 708				vm_wait = true;
 709			}
 710			continue;
 711		}
 712		if (status < 0)
 713			break;
 714		vm_wait = false;
 715	}
 716
 717	switch (status) {
 718	case -ENOTSOCK:
 719		status = -ENOTCONN;
 720		/* Should we call xs_close() here? */
 721		break;
 722	case -EAGAIN:
 723		status = xs_nospace(task);
 724		break;
 725	case -ECONNRESET:
 726	case -ECONNREFUSED:
 727	case -ENOTCONN:
 728	case -EADDRINUSE:
 729	case -ENOBUFS:
 730	case -EPIPE:
 731		break;
 732	default:
 733		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 734			-status);
 735	}
 736
 737	return status;
 738}
 739
 740/**
 741 * xs_tcp_release_xprt - clean up after a tcp transmission
 742 * @xprt: transport
 743 * @task: rpc task
 744 *
 745 * This cleans up if an error causes us to abort the transmission of a request.
 746 * In this case, the socket may need to be reset in order to avoid confusing
 747 * the server.
 748 */
 749static void xs_tcp_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task)
 750{
 751	struct rpc_rqst *req;
 752
 753	if (task != xprt->snd_task)
 754		return;
 755	if (task == NULL)
 756		goto out_release;
 757	req = task->tk_rqstp;
 758	if (req == NULL)
 759		goto out_release;
 760	if (req->rq_bytes_sent == 0)
 761		goto out_release;
 762	if (req->rq_bytes_sent == req->rq_snd_buf.len)
 763		goto out_release;
 764	set_bit(XPRT_CLOSE_WAIT, &xprt->state);
 765out_release:
 766	xprt_release_xprt(xprt, task);
 767}
 768
 769static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
 770{
 771	transport->old_data_ready = sk->sk_data_ready;
 772	transport->old_state_change = sk->sk_state_change;
 773	transport->old_write_space = sk->sk_write_space;
 774	transport->old_error_report = sk->sk_error_report;
 775}
 776
 777static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
 778{
 779	sk->sk_data_ready = transport->old_data_ready;
 780	sk->sk_state_change = transport->old_state_change;
 781	sk->sk_write_space = transport->old_write_space;
 782	sk->sk_error_report = transport->old_error_report;
 783}
 784
 785static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
 786{
 787	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 788
 789	clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
 
 
 
 
 
 
 
 
 
 790}
 791
 792static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
 793{
 794	smp_mb__before_atomic();
 795	clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
 796	clear_bit(XPRT_CLOSING, &xprt->state);
 797	xs_sock_reset_state_flags(xprt);
 798	smp_mb__after_atomic();
 799}
 800
 801static void xs_sock_mark_closed(struct rpc_xprt *xprt)
 802{
 803	xs_sock_reset_connection_flags(xprt);
 804	/* Mark transport as closed and wake up all pending tasks */
 805	xprt_disconnect_done(xprt);
 806}
 807
 808/**
 809 * xs_error_report - callback to handle TCP socket state errors
 810 * @sk: socket
 811 *
 812 * Note: we don't call sock_error() since there may be a rpc_task
 813 * using the socket, and so we don't want to clear sk->sk_err.
 814 */
 815static void xs_error_report(struct sock *sk)
 816{
 
 817	struct rpc_xprt *xprt;
 818	int err;
 819
 820	read_lock_bh(&sk->sk_callback_lock);
 821	if (!(xprt = xprt_from_sock(sk)))
 822		goto out;
 823
 824	err = -sk->sk_err;
 825	if (err == 0)
 
 826		goto out;
 827	/* Is this a reset event? */
 828	if (sk->sk_state == TCP_CLOSE)
 829		xs_sock_mark_closed(xprt);
 830	dprintk("RPC:       xs_error_report client %p, error=%d...\n",
 831			xprt, -err);
 832	trace_rpc_socket_error(xprt, sk->sk_socket, err);
 833	xprt_wake_pending_tasks(xprt, err);
 
 
 
 834 out:
 835	read_unlock_bh(&sk->sk_callback_lock);
 836}
 837
 838static void xs_reset_transport(struct sock_xprt *transport)
 839{
 840	struct socket *sock = transport->sock;
 841	struct sock *sk = transport->inet;
 842	struct rpc_xprt *xprt = &transport->xprt;
 
 843
 844	if (sk == NULL)
 845		return;
 846
 847	if (atomic_read(&transport->xprt.swapper))
 848		sk_clear_memalloc(sk);
 849
 850	kernel_sock_shutdown(sock, SHUT_RDWR);
 851
 852	mutex_lock(&transport->recv_mutex);
 853	write_lock_bh(&sk->sk_callback_lock);
 854	transport->inet = NULL;
 855	transport->sock = NULL;
 
 856
 857	sk->sk_user_data = NULL;
 858
 859	xs_restore_old_callbacks(transport, sk);
 860	xprt_clear_connected(xprt);
 861	write_unlock_bh(&sk->sk_callback_lock);
 862	xs_sock_reset_connection_flags(xprt);
 
 
 863	mutex_unlock(&transport->recv_mutex);
 864
 865	trace_rpc_socket_close(xprt, sock);
 866	sock_release(sock);
 
 
 867}
 868
 869/**
 870 * xs_close - close a socket
 871 * @xprt: transport
 872 *
 873 * This is used when all requests are complete; ie, no DRC state remains
 874 * on the server we want to save.
 875 *
 876 * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
 877 * xs_reset_transport() zeroing the socket from underneath a writer.
 878 */
 879static void xs_close(struct rpc_xprt *xprt)
 880{
 881	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 882
 883	dprintk("RPC:       xs_close xprt %p\n", xprt);
 884
 885	xs_reset_transport(transport);
 886	xprt->reestablish_timeout = 0;
 887
 888	xprt_disconnect_done(xprt);
 889}
 890
 891static void xs_inject_disconnect(struct rpc_xprt *xprt)
 892{
 893	dprintk("RPC:       injecting transport disconnect on xprt=%p\n",
 894		xprt);
 895	xprt_disconnect_done(xprt);
 896}
 897
 898static void xs_xprt_free(struct rpc_xprt *xprt)
 899{
 900	xs_free_peer_addresses(xprt);
 901	xprt_free(xprt);
 902}
 903
 904/**
 905 * xs_destroy - prepare to shutdown a transport
 906 * @xprt: doomed transport
 907 *
 908 */
 909static void xs_destroy(struct rpc_xprt *xprt)
 910{
 911	struct sock_xprt *transport = container_of(xprt,
 912			struct sock_xprt, xprt);
 913	dprintk("RPC:       xs_destroy xprt %p\n", xprt);
 914
 915	cancel_delayed_work_sync(&transport->connect_worker);
 916	xs_close(xprt);
 917	cancel_work_sync(&transport->recv_worker);
 
 918	xs_xprt_free(xprt);
 919	module_put(THIS_MODULE);
 920}
 921
 922static int xs_local_copy_to_xdr(struct xdr_buf *xdr, struct sk_buff *skb)
 923{
 924	struct xdr_skb_reader desc = {
 925		.skb		= skb,
 926		.offset		= sizeof(rpc_fraghdr),
 927		.count		= skb->len - sizeof(rpc_fraghdr),
 928	};
 929
 930	if (xdr_partial_copy_from_skb(xdr, 0, &desc, xdr_skb_read_bits) < 0)
 931		return -1;
 932	if (desc.count)
 933		return -1;
 934	return 0;
 935}
 936
 937/**
 938 * xs_local_data_read_skb
 939 * @xprt: transport
 940 * @sk: socket
 941 * @skb: skbuff
 942 *
 943 * Currently this assumes we can read the whole reply in a single gulp.
 944 */
 945static void xs_local_data_read_skb(struct rpc_xprt *xprt,
 946		struct sock *sk,
 947		struct sk_buff *skb)
 948{
 949	struct rpc_task *task;
 950	struct rpc_rqst *rovr;
 951	int repsize, copied;
 952	u32 _xid;
 953	__be32 *xp;
 954
 955	repsize = skb->len - sizeof(rpc_fraghdr);
 956	if (repsize < 4) {
 957		dprintk("RPC:       impossible RPC reply size %d\n", repsize);
 958		return;
 959	}
 960
 961	/* Copy the XID from the skb... */
 962	xp = skb_header_pointer(skb, sizeof(rpc_fraghdr), sizeof(_xid), &_xid);
 963	if (xp == NULL)
 964		return;
 965
 966	/* Look up and lock the request corresponding to the given XID */
 967	spin_lock_bh(&xprt->transport_lock);
 968	rovr = xprt_lookup_rqst(xprt, *xp);
 969	if (!rovr)
 970		goto out_unlock;
 971	task = rovr->rq_task;
 972
 973	copied = rovr->rq_private_buf.buflen;
 974	if (copied > repsize)
 975		copied = repsize;
 976
 977	if (xs_local_copy_to_xdr(&rovr->rq_private_buf, skb)) {
 978		dprintk("RPC:       sk_buff copy failed\n");
 979		goto out_unlock;
 980	}
 981
 982	xprt_complete_rqst(task, copied);
 983
 984 out_unlock:
 985	spin_unlock_bh(&xprt->transport_lock);
 986}
 987
 988static void xs_local_data_receive(struct sock_xprt *transport)
 989{
 990	struct sk_buff *skb;
 991	struct sock *sk;
 992	int err;
 993
 994	mutex_lock(&transport->recv_mutex);
 995	sk = transport->inet;
 996	if (sk == NULL)
 997		goto out;
 998	for (;;) {
 999		skb = skb_recv_datagram(sk, 0, 1, &err);
1000		if (skb != NULL) {
1001			xs_local_data_read_skb(&transport->xprt, sk, skb);
1002			skb_free_datagram(sk, skb);
1003			continue;
1004		}
1005		if (!test_and_clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1006			break;
1007	}
1008out:
1009	mutex_unlock(&transport->recv_mutex);
1010}
1011
1012static void xs_local_data_receive_workfn(struct work_struct *work)
1013{
1014	struct sock_xprt *transport =
1015		container_of(work, struct sock_xprt, recv_worker);
1016	xs_local_data_receive(transport);
1017}
1018
1019/**
1020 * xs_udp_data_read_skb - receive callback for UDP sockets
1021 * @xprt: transport
1022 * @sk: socket
1023 * @skb: skbuff
1024 *
1025 */
1026static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
1027		struct sock *sk,
1028		struct sk_buff *skb)
1029{
1030	struct rpc_task *task;
1031	struct rpc_rqst *rovr;
1032	int repsize, copied;
1033	u32 _xid;
1034	__be32 *xp;
1035
1036	repsize = skb->len;
1037	if (repsize < 4) {
1038		dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
1039		return;
1040	}
1041
1042	/* Copy the XID from the skb... */
1043	xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
1044	if (xp == NULL)
1045		return;
1046
1047	/* Look up and lock the request corresponding to the given XID */
1048	spin_lock_bh(&xprt->transport_lock);
1049	rovr = xprt_lookup_rqst(xprt, *xp);
1050	if (!rovr)
1051		goto out_unlock;
 
 
 
1052	task = rovr->rq_task;
1053
1054	if ((copied = rovr->rq_private_buf.buflen) > repsize)
1055		copied = repsize;
1056
1057	/* Suck it into the iovec, verify checksum if not done by hw. */
1058	if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
 
1059		__UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
1060		goto out_unlock;
1061	}
1062
1063	__UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
1064
 
1065	xprt_adjust_cwnd(xprt, task, copied);
 
 
1066	xprt_complete_rqst(task, copied);
1067
 
 
1068 out_unlock:
1069	spin_unlock_bh(&xprt->transport_lock);
1070}
1071
1072static void xs_udp_data_receive(struct sock_xprt *transport)
1073{
1074	struct sk_buff *skb;
1075	struct sock *sk;
1076	int err;
1077
1078	mutex_lock(&transport->recv_mutex);
1079	sk = transport->inet;
1080	if (sk == NULL)
1081		goto out;
1082	for (;;) {
1083		skb = skb_recv_udp(sk, 0, 1, &err);
1084		if (skb != NULL) {
1085			xs_udp_data_read_skb(&transport->xprt, sk, skb);
1086			consume_skb(skb);
1087			continue;
1088		}
1089		if (!test_and_clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1090			break;
 
 
 
1091	}
 
1092out:
1093	mutex_unlock(&transport->recv_mutex);
1094}
1095
1096static void xs_udp_data_receive_workfn(struct work_struct *work)
1097{
1098	struct sock_xprt *transport =
1099		container_of(work, struct sock_xprt, recv_worker);
 
 
1100	xs_udp_data_receive(transport);
 
1101}
1102
1103/**
1104 * xs_data_ready - "data ready" callback for UDP sockets
1105 * @sk: socket with data to read
1106 *
1107 */
1108static void xs_data_ready(struct sock *sk)
1109{
1110	struct rpc_xprt *xprt;
1111
1112	read_lock_bh(&sk->sk_callback_lock);
1113	dprintk("RPC:       xs_data_ready...\n");
1114	xprt = xprt_from_sock(sk);
1115	if (xprt != NULL) {
1116		struct sock_xprt *transport = container_of(xprt,
1117				struct sock_xprt, xprt);
1118		transport->old_data_ready(sk);
1119		/* Any data means we had a useful conversation, so
1120		 * then we don't need to delay the next reconnect
1121		 */
1122		if (xprt->reestablish_timeout)
1123			xprt->reestablish_timeout = 0;
1124		if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1125			queue_work(xprtiod_workqueue, &transport->recv_worker);
1126	}
1127	read_unlock_bh(&sk->sk_callback_lock);
1128}
1129
1130/*
1131 * Helper function to force a TCP close if the server is sending
1132 * junk and/or it has put us in CLOSE_WAIT
1133 */
1134static void xs_tcp_force_close(struct rpc_xprt *xprt)
1135{
1136	xprt_force_disconnect(xprt);
1137}
1138
1139static inline void xs_tcp_read_fraghdr(struct rpc_xprt *xprt, struct xdr_skb_reader *desc)
1140{
1141	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1142	size_t len, used;
1143	char *p;
1144
1145	p = ((char *) &transport->tcp_fraghdr) + transport->tcp_offset;
1146	len = sizeof(transport->tcp_fraghdr) - transport->tcp_offset;
1147	used = xdr_skb_read_bits(desc, p, len);
1148	transport->tcp_offset += used;
1149	if (used != len)
1150		return;
1151
1152	transport->tcp_reclen = ntohl(transport->tcp_fraghdr);
1153	if (transport->tcp_reclen & RPC_LAST_STREAM_FRAGMENT)
1154		transport->tcp_flags |= TCP_RCV_LAST_FRAG;
1155	else
1156		transport->tcp_flags &= ~TCP_RCV_LAST_FRAG;
1157	transport->tcp_reclen &= RPC_FRAGMENT_SIZE_MASK;
1158
1159	transport->tcp_flags &= ~TCP_RCV_COPY_FRAGHDR;
1160	transport->tcp_offset = 0;
1161
1162	/* Sanity check of the record length */
1163	if (unlikely(transport->tcp_reclen < 8)) {
1164		dprintk("RPC:       invalid TCP record fragment length\n");
1165		xs_tcp_force_close(xprt);
1166		return;
1167	}
1168	dprintk("RPC:       reading TCP record fragment of length %d\n",
1169			transport->tcp_reclen);
1170}
1171
1172static void xs_tcp_check_fraghdr(struct sock_xprt *transport)
1173{
1174	if (transport->tcp_offset == transport->tcp_reclen) {
1175		transport->tcp_flags |= TCP_RCV_COPY_FRAGHDR;
1176		transport->tcp_offset = 0;
1177		if (transport->tcp_flags & TCP_RCV_LAST_FRAG) {
1178			transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1179			transport->tcp_flags |= TCP_RCV_COPY_XID;
1180			transport->tcp_copied = 0;
1181		}
1182	}
1183}
1184
1185static inline void xs_tcp_read_xid(struct sock_xprt *transport, struct xdr_skb_reader *desc)
1186{
1187	size_t len, used;
1188	char *p;
1189
1190	len = sizeof(transport->tcp_xid) - transport->tcp_offset;
1191	dprintk("RPC:       reading XID (%Zu bytes)\n", len);
1192	p = ((char *) &transport->tcp_xid) + transport->tcp_offset;
1193	used = xdr_skb_read_bits(desc, p, len);
1194	transport->tcp_offset += used;
1195	if (used != len)
1196		return;
1197	transport->tcp_flags &= ~TCP_RCV_COPY_XID;
1198	transport->tcp_flags |= TCP_RCV_READ_CALLDIR;
1199	transport->tcp_copied = 4;
1200	dprintk("RPC:       reading %s XID %08x\n",
1201			(transport->tcp_flags & TCP_RPC_REPLY) ? "reply for"
1202							      : "request with",
1203			ntohl(transport->tcp_xid));
1204	xs_tcp_check_fraghdr(transport);
1205}
1206
1207static inline void xs_tcp_read_calldir(struct sock_xprt *transport,
1208				       struct xdr_skb_reader *desc)
1209{
1210	size_t len, used;
1211	u32 offset;
1212	char *p;
1213
1214	/*
1215	 * We want transport->tcp_offset to be 8 at the end of this routine
1216	 * (4 bytes for the xid and 4 bytes for the call/reply flag).
1217	 * When this function is called for the first time,
1218	 * transport->tcp_offset is 4 (after having already read the xid).
1219	 */
1220	offset = transport->tcp_offset - sizeof(transport->tcp_xid);
1221	len = sizeof(transport->tcp_calldir) - offset;
1222	dprintk("RPC:       reading CALL/REPLY flag (%Zu bytes)\n", len);
1223	p = ((char *) &transport->tcp_calldir) + offset;
1224	used = xdr_skb_read_bits(desc, p, len);
1225	transport->tcp_offset += used;
1226	if (used != len)
1227		return;
1228	transport->tcp_flags &= ~TCP_RCV_READ_CALLDIR;
1229	/*
1230	 * We don't yet have the XDR buffer, so we will write the calldir
1231	 * out after we get the buffer from the 'struct rpc_rqst'
1232	 */
1233	switch (ntohl(transport->tcp_calldir)) {
1234	case RPC_REPLY:
1235		transport->tcp_flags |= TCP_RCV_COPY_CALLDIR;
1236		transport->tcp_flags |= TCP_RCV_COPY_DATA;
1237		transport->tcp_flags |= TCP_RPC_REPLY;
1238		break;
1239	case RPC_CALL:
1240		transport->tcp_flags |= TCP_RCV_COPY_CALLDIR;
1241		transport->tcp_flags |= TCP_RCV_COPY_DATA;
1242		transport->tcp_flags &= ~TCP_RPC_REPLY;
1243		break;
1244	default:
1245		dprintk("RPC:       invalid request message type\n");
1246		xs_tcp_force_close(&transport->xprt);
1247	}
1248	xs_tcp_check_fraghdr(transport);
1249}
1250
1251static inline void xs_tcp_read_common(struct rpc_xprt *xprt,
1252				     struct xdr_skb_reader *desc,
1253				     struct rpc_rqst *req)
1254{
1255	struct sock_xprt *transport =
1256				container_of(xprt, struct sock_xprt, xprt);
1257	struct xdr_buf *rcvbuf;
1258	size_t len;
1259	ssize_t r;
1260
1261	rcvbuf = &req->rq_private_buf;
1262
1263	if (transport->tcp_flags & TCP_RCV_COPY_CALLDIR) {
1264		/*
1265		 * Save the RPC direction in the XDR buffer
1266		 */
1267		memcpy(rcvbuf->head[0].iov_base + transport->tcp_copied,
1268			&transport->tcp_calldir,
1269			sizeof(transport->tcp_calldir));
1270		transport->tcp_copied += sizeof(transport->tcp_calldir);
1271		transport->tcp_flags &= ~TCP_RCV_COPY_CALLDIR;
1272	}
1273
1274	len = desc->count;
1275	if (len > transport->tcp_reclen - transport->tcp_offset) {
1276		struct xdr_skb_reader my_desc;
1277
1278		len = transport->tcp_reclen - transport->tcp_offset;
1279		memcpy(&my_desc, desc, sizeof(my_desc));
1280		my_desc.count = len;
1281		r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied,
1282					  &my_desc, xdr_skb_read_bits);
1283		desc->count -= r;
1284		desc->offset += r;
1285	} else
1286		r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied,
1287					  desc, xdr_skb_read_bits);
1288
1289	if (r > 0) {
1290		transport->tcp_copied += r;
1291		transport->tcp_offset += r;
1292	}
1293	if (r != len) {
1294		/* Error when copying to the receive buffer,
1295		 * usually because we weren't able to allocate
1296		 * additional buffer pages. All we can do now
1297		 * is turn off TCP_RCV_COPY_DATA, so the request
1298		 * will not receive any additional updates,
1299		 * and time out.
1300		 * Any remaining data from this record will
1301		 * be discarded.
1302		 */
1303		transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1304		dprintk("RPC:       XID %08x truncated request\n",
1305				ntohl(transport->tcp_xid));
1306		dprintk("RPC:       xprt = %p, tcp_copied = %lu, "
1307				"tcp_offset = %u, tcp_reclen = %u\n",
1308				xprt, transport->tcp_copied,
1309				transport->tcp_offset, transport->tcp_reclen);
1310		return;
1311	}
1312
1313	dprintk("RPC:       XID %08x read %Zd bytes\n",
1314			ntohl(transport->tcp_xid), r);
1315	dprintk("RPC:       xprt = %p, tcp_copied = %lu, tcp_offset = %u, "
1316			"tcp_reclen = %u\n", xprt, transport->tcp_copied,
1317			transport->tcp_offset, transport->tcp_reclen);
1318
1319	if (transport->tcp_copied == req->rq_private_buf.buflen)
1320		transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1321	else if (transport->tcp_offset == transport->tcp_reclen) {
1322		if (transport->tcp_flags & TCP_RCV_LAST_FRAG)
1323			transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1324	}
1325}
1326
1327/*
1328 * Finds the request corresponding to the RPC xid and invokes the common
1329 * tcp read code to read the data.
1330 */
1331static inline int xs_tcp_read_reply(struct rpc_xprt *xprt,
1332				    struct xdr_skb_reader *desc)
1333{
1334	struct sock_xprt *transport =
1335				container_of(xprt, struct sock_xprt, xprt);
1336	struct rpc_rqst *req;
1337
1338	dprintk("RPC:       read reply XID %08x\n", ntohl(transport->tcp_xid));
1339
1340	/* Find and lock the request corresponding to this xid */
1341	spin_lock_bh(&xprt->transport_lock);
1342	req = xprt_lookup_rqst(xprt, transport->tcp_xid);
1343	if (!req) {
1344		dprintk("RPC:       XID %08x request not found!\n",
1345				ntohl(transport->tcp_xid));
1346		spin_unlock_bh(&xprt->transport_lock);
1347		return -1;
1348	}
1349
1350	xs_tcp_read_common(xprt, desc, req);
1351
1352	if (!(transport->tcp_flags & TCP_RCV_COPY_DATA))
1353		xprt_complete_rqst(req->rq_task, transport->tcp_copied);
1354
1355	spin_unlock_bh(&xprt->transport_lock);
1356	return 0;
1357}
1358
1359#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1360/*
1361 * Obtains an rpc_rqst previously allocated and invokes the common
1362 * tcp read code to read the data.  The result is placed in the callback
1363 * queue.
1364 * If we're unable to obtain the rpc_rqst we schedule the closing of the
1365 * connection and return -1.
1366 */
1367static int xs_tcp_read_callback(struct rpc_xprt *xprt,
1368				       struct xdr_skb_reader *desc)
1369{
1370	struct sock_xprt *transport =
1371				container_of(xprt, struct sock_xprt, xprt);
1372	struct rpc_rqst *req;
1373
1374	/* Look up and lock the request corresponding to the given XID */
1375	spin_lock_bh(&xprt->transport_lock);
1376	req = xprt_lookup_bc_request(xprt, transport->tcp_xid);
1377	if (req == NULL) {
1378		spin_unlock_bh(&xprt->transport_lock);
1379		printk(KERN_WARNING "Callback slot table overflowed\n");
1380		xprt_force_disconnect(xprt);
1381		return -1;
1382	}
1383
1384	dprintk("RPC:       read callback  XID %08x\n", ntohl(req->rq_xid));
1385	xs_tcp_read_common(xprt, desc, req);
1386
1387	if (!(transport->tcp_flags & TCP_RCV_COPY_DATA))
1388		xprt_complete_bc_request(req, transport->tcp_copied);
1389	spin_unlock_bh(&xprt->transport_lock);
1390
1391	return 0;
1392}
1393
1394static inline int _xs_tcp_read_data(struct rpc_xprt *xprt,
1395					struct xdr_skb_reader *desc)
1396{
1397	struct sock_xprt *transport =
1398				container_of(xprt, struct sock_xprt, xprt);
1399
1400	return (transport->tcp_flags & TCP_RPC_REPLY) ?
1401		xs_tcp_read_reply(xprt, desc) :
1402		xs_tcp_read_callback(xprt, desc);
1403}
1404
1405static int xs_tcp_bc_up(struct svc_serv *serv, struct net *net)
1406{
1407	int ret;
1408
1409	ret = svc_create_xprt(serv, "tcp-bc", net, PF_INET, 0,
1410			      SVC_SOCK_ANONYMOUS);
1411	if (ret < 0)
1412		return ret;
1413	return 0;
1414}
1415
1416static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
1417{
1418	return PAGE_SIZE;
1419}
1420#else
1421static inline int _xs_tcp_read_data(struct rpc_xprt *xprt,
1422					struct xdr_skb_reader *desc)
1423{
1424	return xs_tcp_read_reply(xprt, desc);
1425}
1426#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1427
1428/*
1429 * Read data off the transport.  This can be either an RPC_CALL or an
1430 * RPC_REPLY.  Relay the processing to helper functions.
1431 */
1432static void xs_tcp_read_data(struct rpc_xprt *xprt,
1433				    struct xdr_skb_reader *desc)
1434{
1435	struct sock_xprt *transport =
1436				container_of(xprt, struct sock_xprt, xprt);
1437
1438	if (_xs_tcp_read_data(xprt, desc) == 0)
1439		xs_tcp_check_fraghdr(transport);
1440	else {
1441		/*
1442		 * The transport_lock protects the request handling.
1443		 * There's no need to hold it to update the tcp_flags.
1444		 */
1445		transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1446	}
1447}
1448
1449static inline void xs_tcp_read_discard(struct sock_xprt *transport, struct xdr_skb_reader *desc)
1450{
1451	size_t len;
1452
1453	len = transport->tcp_reclen - transport->tcp_offset;
1454	if (len > desc->count)
1455		len = desc->count;
1456	desc->count -= len;
1457	desc->offset += len;
1458	transport->tcp_offset += len;
1459	dprintk("RPC:       discarded %Zu bytes\n", len);
1460	xs_tcp_check_fraghdr(transport);
1461}
1462
1463static int xs_tcp_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, unsigned int offset, size_t len)
1464{
1465	struct rpc_xprt *xprt = rd_desc->arg.data;
1466	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1467	struct xdr_skb_reader desc = {
1468		.skb	= skb,
1469		.offset	= offset,
1470		.count	= len,
1471	};
1472
1473	dprintk("RPC:       xs_tcp_data_recv started\n");
1474	do {
1475		trace_xs_tcp_data_recv(transport);
1476		/* Read in a new fragment marker if necessary */
1477		/* Can we ever really expect to get completely empty fragments? */
1478		if (transport->tcp_flags & TCP_RCV_COPY_FRAGHDR) {
1479			xs_tcp_read_fraghdr(xprt, &desc);
1480			continue;
1481		}
1482		/* Read in the xid if necessary */
1483		if (transport->tcp_flags & TCP_RCV_COPY_XID) {
1484			xs_tcp_read_xid(transport, &desc);
1485			continue;
1486		}
1487		/* Read in the call/reply flag */
1488		if (transport->tcp_flags & TCP_RCV_READ_CALLDIR) {
1489			xs_tcp_read_calldir(transport, &desc);
1490			continue;
1491		}
1492		/* Read in the request data */
1493		if (transport->tcp_flags & TCP_RCV_COPY_DATA) {
1494			xs_tcp_read_data(xprt, &desc);
1495			continue;
1496		}
1497		/* Skip over any trailing bytes on short reads */
1498		xs_tcp_read_discard(transport, &desc);
1499	} while (desc.count);
1500	trace_xs_tcp_data_recv(transport);
1501	dprintk("RPC:       xs_tcp_data_recv done\n");
1502	return len - desc.count;
1503}
1504
1505static void xs_tcp_data_receive(struct sock_xprt *transport)
1506{
1507	struct rpc_xprt *xprt = &transport->xprt;
1508	struct sock *sk;
1509	read_descriptor_t rd_desc = {
1510		.count = 2*1024*1024,
1511		.arg.data = xprt,
1512	};
1513	unsigned long total = 0;
1514	int read = 0;
1515
1516	mutex_lock(&transport->recv_mutex);
1517	sk = transport->inet;
1518	if (sk == NULL)
1519		goto out;
1520
1521	/* We use rd_desc to pass struct xprt to xs_tcp_data_recv */
1522	for (;;) {
1523		lock_sock(sk);
1524		read = tcp_read_sock(sk, &rd_desc, xs_tcp_data_recv);
1525		if (read <= 0) {
1526			clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1527			release_sock(sk);
1528			if (!test_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1529				break;
1530		} else {
1531			release_sock(sk);
1532			total += read;
1533		}
1534		rd_desc.count = 65536;
1535	}
1536out:
1537	mutex_unlock(&transport->recv_mutex);
1538	trace_xs_tcp_data_ready(xprt, read, total);
1539}
1540
1541static void xs_tcp_data_receive_workfn(struct work_struct *work)
1542{
1543	struct sock_xprt *transport =
1544		container_of(work, struct sock_xprt, recv_worker);
1545	xs_tcp_data_receive(transport);
1546}
1547
1548/**
1549 * xs_tcp_state_change - callback to handle TCP socket state changes
1550 * @sk: socket whose state has changed
1551 *
1552 */
1553static void xs_tcp_state_change(struct sock *sk)
1554{
1555	struct rpc_xprt *xprt;
1556	struct sock_xprt *transport;
1557
1558	read_lock_bh(&sk->sk_callback_lock);
1559	if (!(xprt = xprt_from_sock(sk)))
1560		goto out;
1561	dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1562	dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1563			sk->sk_state, xprt_connected(xprt),
1564			sock_flag(sk, SOCK_DEAD),
1565			sock_flag(sk, SOCK_ZAPPED),
1566			sk->sk_shutdown);
1567
1568	transport = container_of(xprt, struct sock_xprt, xprt);
1569	trace_rpc_socket_state_change(xprt, sk->sk_socket);
1570	switch (sk->sk_state) {
1571	case TCP_ESTABLISHED:
1572		spin_lock(&xprt->transport_lock);
1573		if (!xprt_test_and_set_connected(xprt)) {
1574
1575			/* Reset TCP record info */
1576			transport->tcp_offset = 0;
1577			transport->tcp_reclen = 0;
1578			transport->tcp_copied = 0;
1579			transport->tcp_flags =
1580				TCP_RCV_COPY_FRAGHDR | TCP_RCV_COPY_XID;
1581			xprt->connect_cookie++;
1582			clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
1583			xprt_clear_connecting(xprt);
1584
1585			xprt_wake_pending_tasks(xprt, -EAGAIN);
 
 
 
1586		}
1587		spin_unlock(&xprt->transport_lock);
1588		break;
1589	case TCP_FIN_WAIT1:
1590		/* The client initiated a shutdown of the socket */
1591		xprt->connect_cookie++;
1592		xprt->reestablish_timeout = 0;
1593		set_bit(XPRT_CLOSING, &xprt->state);
1594		smp_mb__before_atomic();
1595		clear_bit(XPRT_CONNECTED, &xprt->state);
1596		clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1597		smp_mb__after_atomic();
1598		break;
1599	case TCP_CLOSE_WAIT:
1600		/* The server initiated a shutdown of the socket */
1601		xprt->connect_cookie++;
1602		clear_bit(XPRT_CONNECTED, &xprt->state);
1603		xs_tcp_force_close(xprt);
 
1604	case TCP_CLOSING:
1605		/*
1606		 * If the server closed down the connection, make sure that
1607		 * we back off before reconnecting
1608		 */
1609		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1610			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1611		break;
1612	case TCP_LAST_ACK:
1613		set_bit(XPRT_CLOSING, &xprt->state);
1614		smp_mb__before_atomic();
1615		clear_bit(XPRT_CONNECTED, &xprt->state);
1616		smp_mb__after_atomic();
1617		break;
1618	case TCP_CLOSE:
1619		if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
1620					&transport->sock_state))
1621			xprt_clear_connecting(xprt);
1622		xs_sock_mark_closed(xprt);
 
 
1623	}
1624 out:
1625	read_unlock_bh(&sk->sk_callback_lock);
1626}
1627
1628static void xs_write_space(struct sock *sk)
1629{
1630	struct socket_wq *wq;
 
1631	struct rpc_xprt *xprt;
1632
1633	if (!sk->sk_socket)
1634		return;
1635	clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1636
1637	if (unlikely(!(xprt = xprt_from_sock(sk))))
1638		return;
 
1639	rcu_read_lock();
1640	wq = rcu_dereference(sk->sk_wq);
1641	if (!wq || test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags) == 0)
1642		goto out;
1643
1644	xprt_write_space(xprt);
 
1645out:
1646	rcu_read_unlock();
1647}
1648
1649/**
1650 * xs_udp_write_space - callback invoked when socket buffer space
1651 *                             becomes available
1652 * @sk: socket whose state has changed
1653 *
1654 * Called when more output buffer space is available for this socket.
1655 * We try not to wake our writers until they can make "significant"
1656 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1657 * with a bunch of small requests.
1658 */
1659static void xs_udp_write_space(struct sock *sk)
1660{
1661	read_lock_bh(&sk->sk_callback_lock);
1662
1663	/* from net/core/sock.c:sock_def_write_space */
1664	if (sock_writeable(sk))
1665		xs_write_space(sk);
1666
1667	read_unlock_bh(&sk->sk_callback_lock);
1668}
1669
1670/**
1671 * xs_tcp_write_space - callback invoked when socket buffer space
1672 *                             becomes available
1673 * @sk: socket whose state has changed
1674 *
1675 * Called when more output buffer space is available for this socket.
1676 * We try not to wake our writers until they can make "significant"
1677 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1678 * with a bunch of small requests.
1679 */
1680static void xs_tcp_write_space(struct sock *sk)
1681{
1682	read_lock_bh(&sk->sk_callback_lock);
1683
1684	/* from net/core/stream.c:sk_stream_write_space */
1685	if (sk_stream_is_writeable(sk))
1686		xs_write_space(sk);
1687
1688	read_unlock_bh(&sk->sk_callback_lock);
1689}
1690
1691static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1692{
1693	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1694	struct sock *sk = transport->inet;
1695
1696	if (transport->rcvsize) {
1697		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1698		sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1699	}
1700	if (transport->sndsize) {
1701		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1702		sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1703		sk->sk_write_space(sk);
1704	}
1705}
1706
1707/**
1708 * xs_udp_set_buffer_size - set send and receive limits
1709 * @xprt: generic transport
1710 * @sndsize: requested size of send buffer, in bytes
1711 * @rcvsize: requested size of receive buffer, in bytes
1712 *
1713 * Set socket send and receive buffer size limits.
1714 */
1715static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1716{
1717	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1718
1719	transport->sndsize = 0;
1720	if (sndsize)
1721		transport->sndsize = sndsize + 1024;
1722	transport->rcvsize = 0;
1723	if (rcvsize)
1724		transport->rcvsize = rcvsize + 1024;
1725
1726	xs_udp_do_set_buffer_size(xprt);
1727}
1728
1729/**
1730 * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
 
1731 * @task: task that timed out
1732 *
1733 * Adjust the congestion window after a retransmit timeout has occurred.
1734 */
1735static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1736{
 
1737	xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
 
1738}
1739
1740static unsigned short xs_get_random_port(void)
1741{
1742	unsigned short range = xprt_max_resvport - xprt_min_resvport + 1;
1743	unsigned short rand = (unsigned short) prandom_u32() % range;
1744	return rand + xprt_min_resvport;
 
 
 
 
 
 
1745}
1746
1747/**
1748 * xs_set_reuseaddr_port - set the socket's port and address reuse options
1749 * @sock: socket
1750 *
1751 * Note that this function has to be called on all sockets that share the
1752 * same port, and it must be called before binding.
1753 */
1754static void xs_sock_set_reuseport(struct socket *sock)
1755{
1756	int opt = 1;
1757
1758	kernel_setsockopt(sock, SOL_SOCKET, SO_REUSEPORT,
1759			(char *)&opt, sizeof(opt));
1760}
1761
1762static unsigned short xs_sock_getport(struct socket *sock)
1763{
1764	struct sockaddr_storage buf;
1765	int buflen;
1766	unsigned short port = 0;
1767
1768	if (kernel_getsockname(sock, (struct sockaddr *)&buf, &buflen) < 0)
1769		goto out;
1770	switch (buf.ss_family) {
1771	case AF_INET6:
1772		port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1773		break;
1774	case AF_INET:
1775		port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1776	}
1777out:
1778	return port;
1779}
1780
1781/**
1782 * xs_set_port - reset the port number in the remote endpoint address
1783 * @xprt: generic transport
1784 * @port: new port number
1785 *
1786 */
1787static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1788{
1789	dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1790
1791	rpc_set_port(xs_addr(xprt), port);
1792	xs_update_peer_port(xprt);
1793}
1794
1795static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1796{
1797	if (transport->srcport == 0)
1798		transport->srcport = xs_sock_getport(sock);
1799}
1800
1801static unsigned short xs_get_srcport(struct sock_xprt *transport)
1802{
1803	unsigned short port = transport->srcport;
1804
1805	if (port == 0 && transport->xprt.resvport)
1806		port = xs_get_random_port();
1807	return port;
1808}
1809
1810static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1811{
1812	if (transport->srcport != 0)
1813		transport->srcport = 0;
1814	if (!transport->xprt.resvport)
1815		return 0;
1816	if (port <= xprt_min_resvport || port > xprt_max_resvport)
1817		return xprt_max_resvport;
1818	return --port;
1819}
1820static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1821{
1822	struct sockaddr_storage myaddr;
1823	int err, nloop = 0;
1824	unsigned short port = xs_get_srcport(transport);
1825	unsigned short last;
1826
1827	/*
1828	 * If we are asking for any ephemeral port (i.e. port == 0 &&
1829	 * transport->xprt.resvport == 0), don't bind.  Let the local
1830	 * port selection happen implicitly when the socket is used
1831	 * (for example at connect time).
1832	 *
1833	 * This ensures that we can continue to establish TCP
1834	 * connections even when all local ephemeral ports are already
1835	 * a part of some TCP connection.  This makes no difference
1836	 * for UDP sockets, but also doens't harm them.
1837	 *
1838	 * If we're asking for any reserved port (i.e. port == 0 &&
1839	 * transport->xprt.resvport == 1) xs_get_srcport above will
1840	 * ensure that port is non-zero and we will bind as needed.
1841	 */
1842	if (port == 0)
1843		return 0;
1844
1845	memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1846	do {
1847		rpc_set_port((struct sockaddr *)&myaddr, port);
1848		err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1849				transport->xprt.addrlen);
1850		if (err == 0) {
1851			transport->srcport = port;
1852			break;
1853		}
1854		last = port;
1855		port = xs_next_srcport(transport, port);
1856		if (port > last)
1857			nloop++;
1858	} while (err == -EADDRINUSE && nloop != 2);
1859
1860	if (myaddr.ss_family == AF_INET)
1861		dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1862				&((struct sockaddr_in *)&myaddr)->sin_addr,
1863				port, err ? "failed" : "ok", err);
1864	else
1865		dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1866				&((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1867				port, err ? "failed" : "ok", err);
1868	return err;
1869}
1870
1871/*
1872 * We don't support autobind on AF_LOCAL sockets
1873 */
1874static void xs_local_rpcbind(struct rpc_task *task)
1875{
1876	xprt_set_bound(task->tk_xprt);
1877}
1878
1879static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1880{
1881}
1882
1883#ifdef CONFIG_DEBUG_LOCK_ALLOC
1884static struct lock_class_key xs_key[2];
1885static struct lock_class_key xs_slock_key[2];
1886
1887static inline void xs_reclassify_socketu(struct socket *sock)
1888{
1889	struct sock *sk = sock->sk;
1890
1891	sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1892		&xs_slock_key[1], "sk_lock-AF_LOCAL-RPC", &xs_key[1]);
1893}
1894
1895static inline void xs_reclassify_socket4(struct socket *sock)
1896{
1897	struct sock *sk = sock->sk;
1898
1899	sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1900		&xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1901}
1902
1903static inline void xs_reclassify_socket6(struct socket *sock)
1904{
1905	struct sock *sk = sock->sk;
1906
1907	sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1908		&xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1909}
1910
1911static inline void xs_reclassify_socket(int family, struct socket *sock)
1912{
1913	if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
1914		return;
1915
1916	switch (family) {
1917	case AF_LOCAL:
1918		xs_reclassify_socketu(sock);
1919		break;
1920	case AF_INET:
1921		xs_reclassify_socket4(sock);
1922		break;
1923	case AF_INET6:
1924		xs_reclassify_socket6(sock);
1925		break;
1926	}
1927}
1928#else
1929static inline void xs_reclassify_socket(int family, struct socket *sock)
1930{
1931}
1932#endif
1933
1934static void xs_dummy_setup_socket(struct work_struct *work)
1935{
1936}
1937
1938static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1939		struct sock_xprt *transport, int family, int type,
1940		int protocol, bool reuseport)
1941{
 
1942	struct socket *sock;
1943	int err;
1944
1945	err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1946	if (err < 0) {
1947		dprintk("RPC:       can't create %d transport socket (%d).\n",
1948				protocol, -err);
1949		goto out;
1950	}
1951	xs_reclassify_socket(family, sock);
1952
1953	if (reuseport)
1954		xs_sock_set_reuseport(sock);
1955
1956	err = xs_bind(transport, sock);
1957	if (err) {
1958		sock_release(sock);
1959		goto out;
1960	}
1961
 
 
 
 
 
1962	return sock;
1963out:
1964	return ERR_PTR(err);
1965}
1966
1967static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1968				      struct socket *sock)
1969{
1970	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1971									xprt);
1972
1973	if (!transport->inet) {
1974		struct sock *sk = sock->sk;
1975
1976		write_lock_bh(&sk->sk_callback_lock);
1977
1978		xs_save_old_callbacks(transport, sk);
1979
1980		sk->sk_user_data = xprt;
1981		sk->sk_data_ready = xs_data_ready;
1982		sk->sk_write_space = xs_udp_write_space;
1983		sock_set_flag(sk, SOCK_FASYNC);
1984		sk->sk_error_report = xs_error_report;
1985		sk->sk_allocation = GFP_NOIO;
1986
1987		xprt_clear_connected(xprt);
1988
1989		/* Reset to new socket */
1990		transport->sock = sock;
1991		transport->inet = sk;
1992
1993		write_unlock_bh(&sk->sk_callback_lock);
1994	}
1995
1996	/* Tell the socket layer to start connecting... */
1997	xprt->stat.connect_count++;
1998	xprt->stat.connect_start = jiffies;
1999	return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
2000}
2001
2002/**
2003 * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
2004 * @transport: socket transport to connect
2005 */
2006static int xs_local_setup_socket(struct sock_xprt *transport)
2007{
2008	struct rpc_xprt *xprt = &transport->xprt;
 
2009	struct socket *sock;
2010	int status = -EIO;
2011
2012	status = __sock_create(xprt->xprt_net, AF_LOCAL,
2013					SOCK_STREAM, 0, &sock, 1);
2014	if (status < 0) {
2015		dprintk("RPC:       can't create AF_LOCAL "
2016			"transport socket (%d).\n", -status);
2017		goto out;
2018	}
2019	xs_reclassify_socket(AF_LOCAL, sock);
2020
 
 
 
 
 
 
 
2021	dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
2022			xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2023
2024	status = xs_local_finish_connecting(xprt, sock);
2025	trace_rpc_socket_connect(xprt, sock, status);
2026	switch (status) {
2027	case 0:
2028		dprintk("RPC:       xprt %p connected to %s\n",
2029				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
 
 
 
2030		xprt_set_connected(xprt);
2031	case -ENOBUFS:
2032		break;
2033	case -ENOENT:
2034		dprintk("RPC:       xprt %p: socket %s does not exist\n",
2035				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2036		break;
2037	case -ECONNREFUSED:
2038		dprintk("RPC:       xprt %p: connection refused for %s\n",
2039				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2040		break;
2041	default:
2042		printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
2043				__func__, -status,
2044				xprt->address_strings[RPC_DISPLAY_ADDR]);
2045	}
2046
2047out:
2048	xprt_clear_connecting(xprt);
2049	xprt_wake_pending_tasks(xprt, status);
2050	return status;
2051}
2052
2053static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2054{
2055	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2056	int ret;
2057
2058	 if (RPC_IS_ASYNC(task)) {
2059		/*
2060		 * We want the AF_LOCAL connect to be resolved in the
2061		 * filesystem namespace of the process making the rpc
2062		 * call.  Thus we connect synchronously.
2063		 *
2064		 * If we want to support asynchronous AF_LOCAL calls,
2065		 * we'll need to figure out how to pass a namespace to
2066		 * connect.
2067		 */
 
2068		rpc_exit(task, -ENOTCONN);
2069		return;
2070	}
2071	ret = xs_local_setup_socket(transport);
2072	if (ret && !RPC_IS_SOFTCONN(task))
2073		msleep_interruptible(15000);
2074}
2075
2076#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
2077/*
2078 * Note that this should be called with XPRT_LOCKED held (or when we otherwise
2079 * know that we have exclusive access to the socket), to guard against
2080 * races with xs_reset_transport.
2081 */
2082static void xs_set_memalloc(struct rpc_xprt *xprt)
2083{
2084	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
2085			xprt);
2086
2087	/*
2088	 * If there's no sock, then we have nothing to set. The
2089	 * reconnecting process will get it for us.
2090	 */
2091	if (!transport->inet)
2092		return;
2093	if (atomic_read(&xprt->swapper))
2094		sk_set_memalloc(transport->inet);
2095}
2096
2097/**
2098 * xs_enable_swap - Tag this transport as being used for swap.
2099 * @xprt: transport to tag
2100 *
2101 * Take a reference to this transport on behalf of the rpc_clnt, and
2102 * optionally mark it for swapping if it wasn't already.
2103 */
2104static int
2105xs_enable_swap(struct rpc_xprt *xprt)
2106{
2107	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2108
2109	if (atomic_inc_return(&xprt->swapper) != 1)
2110		return 0;
2111	if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2112		return -ERESTARTSYS;
2113	if (xs->inet)
2114		sk_set_memalloc(xs->inet);
2115	xprt_release_xprt(xprt, NULL);
2116	return 0;
2117}
2118
2119/**
2120 * xs_disable_swap - Untag this transport as being used for swap.
2121 * @xprt: transport to tag
2122 *
2123 * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
2124 * swapper refcount goes to 0, untag the socket as a memalloc socket.
2125 */
2126static void
2127xs_disable_swap(struct rpc_xprt *xprt)
2128{
2129	struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2130
2131	if (!atomic_dec_and_test(&xprt->swapper))
2132		return;
2133	if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2134		return;
2135	if (xs->inet)
2136		sk_clear_memalloc(xs->inet);
2137	xprt_release_xprt(xprt, NULL);
2138}
2139#else
2140static void xs_set_memalloc(struct rpc_xprt *xprt)
2141{
2142}
2143
2144static int
2145xs_enable_swap(struct rpc_xprt *xprt)
2146{
2147	return -EINVAL;
2148}
2149
2150static void
2151xs_disable_swap(struct rpc_xprt *xprt)
2152{
2153}
2154#endif
2155
2156static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2157{
2158	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2159
2160	if (!transport->inet) {
2161		struct sock *sk = sock->sk;
2162
2163		write_lock_bh(&sk->sk_callback_lock);
2164
2165		xs_save_old_callbacks(transport, sk);
2166
2167		sk->sk_user_data = xprt;
2168		sk->sk_data_ready = xs_data_ready;
2169		sk->sk_write_space = xs_udp_write_space;
2170		sock_set_flag(sk, SOCK_FASYNC);
2171		sk->sk_allocation = GFP_NOIO;
2172
2173		xprt_set_connected(xprt);
2174
2175		/* Reset to new socket */
2176		transport->sock = sock;
2177		transport->inet = sk;
2178
2179		xs_set_memalloc(xprt);
2180
2181		write_unlock_bh(&sk->sk_callback_lock);
2182	}
2183	xs_udp_do_set_buffer_size(xprt);
2184
2185	xprt->stat.connect_start = jiffies;
2186}
2187
2188static void xs_udp_setup_socket(struct work_struct *work)
2189{
2190	struct sock_xprt *transport =
2191		container_of(work, struct sock_xprt, connect_worker.work);
2192	struct rpc_xprt *xprt = &transport->xprt;
2193	struct socket *sock = transport->sock;
2194	int status = -EIO;
2195
2196	sock = xs_create_sock(xprt, transport,
2197			xs_addr(xprt)->sa_family, SOCK_DGRAM,
2198			IPPROTO_UDP, false);
2199	if (IS_ERR(sock))
2200		goto out;
2201
2202	dprintk("RPC:       worker connecting xprt %p via %s to "
2203				"%s (port %s)\n", xprt,
2204			xprt->address_strings[RPC_DISPLAY_PROTO],
2205			xprt->address_strings[RPC_DISPLAY_ADDR],
2206			xprt->address_strings[RPC_DISPLAY_PORT]);
2207
2208	xs_udp_finish_connecting(xprt, sock);
2209	trace_rpc_socket_connect(xprt, sock, 0);
2210	status = 0;
2211out:
 
2212	xprt_unlock_connect(xprt, transport);
2213	xprt_clear_connecting(xprt);
2214	xprt_wake_pending_tasks(xprt, status);
2215}
2216
2217/**
2218 * xs_tcp_shutdown - gracefully shut down a TCP socket
2219 * @xprt: transport
2220 *
2221 * Initiates a graceful shutdown of the TCP socket by calling the
2222 * equivalent of shutdown(SHUT_RDWR);
2223 */
2224static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2225{
2226	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2227	struct socket *sock = transport->sock;
 
2228
2229	if (sock == NULL)
2230		return;
2231	if (xprt_connected(xprt)) {
 
2232		kernel_sock_shutdown(sock, SHUT_RDWR);
2233		trace_rpc_socket_shutdown(xprt, sock);
2234	} else
 
 
2235		xs_reset_transport(transport);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2236}
2237
2238static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2239{
2240	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2241	int ret = -ENOTCONN;
2242
2243	if (!transport->inet) {
2244		struct sock *sk = sock->sk;
2245		unsigned int keepidle = xprt->timeout->to_initval / HZ;
2246		unsigned int keepcnt = xprt->timeout->to_retries + 1;
2247		unsigned int opt_on = 1;
2248		unsigned int timeo;
2249		unsigned int addr_pref = IPV6_PREFER_SRC_PUBLIC;
2250
2251		/* TCP Keepalive options */
2252		kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
2253				(char *)&opt_on, sizeof(opt_on));
2254		kernel_setsockopt(sock, SOL_TCP, TCP_KEEPIDLE,
2255				(char *)&keepidle, sizeof(keepidle));
2256		kernel_setsockopt(sock, SOL_TCP, TCP_KEEPINTVL,
2257				(char *)&keepidle, sizeof(keepidle));
2258		kernel_setsockopt(sock, SOL_TCP, TCP_KEEPCNT,
2259				(char *)&keepcnt, sizeof(keepcnt));
2260
2261		/* Avoid temporary address, they are bad for long-lived
2262		 * connections such as NFS mounts.
2263		 * RFC4941, section 3.6 suggests that:
2264		 *    Individual applications, which have specific
2265		 *    knowledge about the normal duration of connections,
2266		 *    MAY override this as appropriate.
2267		 */
2268		kernel_setsockopt(sock, SOL_IPV6, IPV6_ADDR_PREFERENCES,
2269				(char *)&addr_pref, sizeof(addr_pref));
2270
2271		/* TCP user timeout (see RFC5482) */
2272		timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2273			(xprt->timeout->to_retries + 1);
2274		kernel_setsockopt(sock, SOL_TCP, TCP_USER_TIMEOUT,
2275				(char *)&timeo, sizeof(timeo));
2276
2277		write_lock_bh(&sk->sk_callback_lock);
2278
2279		xs_save_old_callbacks(transport, sk);
2280
2281		sk->sk_user_data = xprt;
2282		sk->sk_data_ready = xs_data_ready;
2283		sk->sk_state_change = xs_tcp_state_change;
2284		sk->sk_write_space = xs_tcp_write_space;
2285		sock_set_flag(sk, SOCK_FASYNC);
2286		sk->sk_error_report = xs_error_report;
2287		sk->sk_allocation = GFP_NOIO;
2288
2289		/* socket options */
2290		sock_reset_flag(sk, SOCK_LINGER);
2291		tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
2292
2293		xprt_clear_connected(xprt);
2294
2295		/* Reset to new socket */
2296		transport->sock = sock;
2297		transport->inet = sk;
2298
2299		write_unlock_bh(&sk->sk_callback_lock);
2300	}
2301
2302	if (!xprt_bound(xprt))
2303		goto out;
2304
2305	xs_set_memalloc(xprt);
2306
 
 
2307	/* Tell the socket layer to start connecting... */
2308	xprt->stat.connect_count++;
2309	xprt->stat.connect_start = jiffies;
2310	set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2311	ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2312	switch (ret) {
2313	case 0:
2314		xs_set_srcport(transport, sock);
 
2315	case -EINPROGRESS:
2316		/* SYN_SENT! */
2317		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2318			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2319		break;
2320	case -EADDRNOTAVAIL:
2321		/* Source port number is unavailable. Try a new one! */
2322		transport->srcport = 0;
2323	}
2324out:
2325	return ret;
2326}
2327
2328/**
2329 * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
 
2330 *
2331 * Invoked by a work queue tasklet.
2332 */
2333static void xs_tcp_setup_socket(struct work_struct *work)
2334{
2335	struct sock_xprt *transport =
2336		container_of(work, struct sock_xprt, connect_worker.work);
2337	struct socket *sock = transport->sock;
2338	struct rpc_xprt *xprt = &transport->xprt;
2339	int status = -EIO;
2340
2341	if (!sock) {
2342		sock = xs_create_sock(xprt, transport,
2343				xs_addr(xprt)->sa_family, SOCK_STREAM,
2344				IPPROTO_TCP, true);
2345		if (IS_ERR(sock)) {
2346			status = PTR_ERR(sock);
2347			goto out;
2348		}
2349	}
2350
2351	dprintk("RPC:       worker connecting xprt %p via %s to "
2352				"%s (port %s)\n", xprt,
2353			xprt->address_strings[RPC_DISPLAY_PROTO],
2354			xprt->address_strings[RPC_DISPLAY_ADDR],
2355			xprt->address_strings[RPC_DISPLAY_PORT]);
2356
2357	status = xs_tcp_finish_connecting(xprt, sock);
2358	trace_rpc_socket_connect(xprt, sock, status);
2359	dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2360			xprt, -status, xprt_connected(xprt),
2361			sock->sk->sk_state);
2362	switch (status) {
2363	default:
2364		printk("%s: connect returned unhandled error %d\n",
2365			__func__, status);
 
2366	case -EADDRNOTAVAIL:
2367		/* We're probably in TIME_WAIT. Get rid of existing socket,
2368		 * and retry
2369		 */
2370		xs_tcp_force_close(xprt);
2371		break;
2372	case 0:
2373	case -EINPROGRESS:
2374	case -EALREADY:
2375		xprt_unlock_connect(xprt, transport);
2376		return;
2377	case -EINVAL:
2378		/* Happens, for instance, if the user specified a link
2379		 * local IPv6 address without a scope-id.
2380		 */
2381	case -ECONNREFUSED:
2382	case -ECONNRESET:
 
2383	case -ENETUNREACH:
 
2384	case -EADDRINUSE:
2385	case -ENOBUFS:
2386		/* retry with existing socket, after a delay */
 
 
 
 
 
2387		xs_tcp_force_close(xprt);
2388		goto out;
2389	}
2390	status = -EAGAIN;
2391out:
 
2392	xprt_unlock_connect(xprt, transport);
2393	xprt_clear_connecting(xprt);
2394	xprt_wake_pending_tasks(xprt, status);
2395}
2396
2397static unsigned long xs_reconnect_delay(const struct rpc_xprt *xprt)
2398{
2399	unsigned long start, now = jiffies;
2400
2401	start = xprt->stat.connect_start + xprt->reestablish_timeout;
2402	if (time_after(start, now))
2403		return start - now;
2404	return 0;
2405}
2406
2407static void xs_reconnect_backoff(struct rpc_xprt *xprt)
2408{
2409	xprt->reestablish_timeout <<= 1;
2410	if (xprt->reestablish_timeout > xprt->max_reconnect_timeout)
2411		xprt->reestablish_timeout = xprt->max_reconnect_timeout;
2412	if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2413		xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2414}
2415
2416/**
2417 * xs_connect - connect a socket to a remote endpoint
2418 * @xprt: pointer to transport structure
2419 * @task: address of RPC task that manages state of connect request
2420 *
2421 * TCP: If the remote end dropped the connection, delay reconnecting.
2422 *
2423 * UDP socket connects are synchronous, but we use a work queue anyway
2424 * to guarantee that even unprivileged user processes can set up a
2425 * socket on a privileged port.
2426 *
2427 * If a UDP socket connect fails, the delay behavior here prevents
2428 * retry floods (hard mounts).
2429 */
2430static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2431{
2432	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2433	unsigned long delay = 0;
2434
2435	WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2436
2437	if (transport->sock != NULL) {
2438		dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2439				"seconds\n",
2440				xprt, xprt->reestablish_timeout / HZ);
2441
2442		/* Start by resetting any existing state */
2443		xs_reset_transport(transport);
2444
2445		delay = xs_reconnect_delay(xprt);
2446		xs_reconnect_backoff(xprt);
2447
2448	} else
2449		dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2450
2451	queue_delayed_work(xprtiod_workqueue,
2452			&transport->connect_worker,
2453			delay);
2454}
2455
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2456/**
2457 * xs_local_print_stats - display AF_LOCAL socket-specifc stats
2458 * @xprt: rpc_xprt struct containing statistics
2459 * @seq: output file
2460 *
2461 */
2462static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2463{
2464	long idle_time = 0;
2465
2466	if (xprt_connected(xprt))
2467		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2468
2469	seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2470			"%llu %llu %lu %llu %llu\n",
2471			xprt->stat.bind_count,
2472			xprt->stat.connect_count,
2473			xprt->stat.connect_time,
2474			idle_time,
2475			xprt->stat.sends,
2476			xprt->stat.recvs,
2477			xprt->stat.bad_xids,
2478			xprt->stat.req_u,
2479			xprt->stat.bklog_u,
2480			xprt->stat.max_slots,
2481			xprt->stat.sending_u,
2482			xprt->stat.pending_u);
2483}
2484
2485/**
2486 * xs_udp_print_stats - display UDP socket-specifc stats
2487 * @xprt: rpc_xprt struct containing statistics
2488 * @seq: output file
2489 *
2490 */
2491static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2492{
2493	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2494
2495	seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2496			"%lu %llu %llu\n",
2497			transport->srcport,
2498			xprt->stat.bind_count,
2499			xprt->stat.sends,
2500			xprt->stat.recvs,
2501			xprt->stat.bad_xids,
2502			xprt->stat.req_u,
2503			xprt->stat.bklog_u,
2504			xprt->stat.max_slots,
2505			xprt->stat.sending_u,
2506			xprt->stat.pending_u);
2507}
2508
2509/**
2510 * xs_tcp_print_stats - display TCP socket-specifc stats
2511 * @xprt: rpc_xprt struct containing statistics
2512 * @seq: output file
2513 *
2514 */
2515static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2516{
2517	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2518	long idle_time = 0;
2519
2520	if (xprt_connected(xprt))
2521		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2522
2523	seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2524			"%llu %llu %lu %llu %llu\n",
2525			transport->srcport,
2526			xprt->stat.bind_count,
2527			xprt->stat.connect_count,
2528			xprt->stat.connect_time,
2529			idle_time,
2530			xprt->stat.sends,
2531			xprt->stat.recvs,
2532			xprt->stat.bad_xids,
2533			xprt->stat.req_u,
2534			xprt->stat.bklog_u,
2535			xprt->stat.max_slots,
2536			xprt->stat.sending_u,
2537			xprt->stat.pending_u);
2538}
2539
2540/*
2541 * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2542 * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2543 * to use the server side send routines.
2544 */
2545static int bc_malloc(struct rpc_task *task)
2546{
2547	struct rpc_rqst *rqst = task->tk_rqstp;
2548	size_t size = rqst->rq_callsize;
2549	struct page *page;
2550	struct rpc_buffer *buf;
2551
2552	if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2553		WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2554			  size);
2555		return -EINVAL;
2556	}
2557
2558	page = alloc_page(GFP_KERNEL);
2559	if (!page)
2560		return -ENOMEM;
2561
2562	buf = page_address(page);
2563	buf->len = PAGE_SIZE;
2564
2565	rqst->rq_buffer = buf->data;
2566	rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2567	return 0;
2568}
2569
2570/*
2571 * Free the space allocated in the bc_alloc routine
2572 */
2573static void bc_free(struct rpc_task *task)
2574{
2575	void *buffer = task->tk_rqstp->rq_buffer;
2576	struct rpc_buffer *buf;
2577
2578	buf = container_of(buffer, struct rpc_buffer, data);
2579	free_page((unsigned long)buf);
2580}
2581
2582/*
2583 * Use the svc_sock to send the callback. Must be called with svsk->sk_mutex
2584 * held. Borrows heavily from svc_tcp_sendto and xs_tcp_send_request.
2585 */
2586static int bc_sendto(struct rpc_rqst *req)
2587{
2588	int len;
2589	struct xdr_buf *xbufp = &req->rq_snd_buf;
2590	struct rpc_xprt *xprt = req->rq_xprt;
2591	struct sock_xprt *transport =
2592				container_of(xprt, struct sock_xprt, xprt);
2593	struct socket *sock = transport->sock;
2594	unsigned long headoff;
2595	unsigned long tailoff;
 
 
 
 
 
 
 
 
 
 
2596
2597	xs_encode_stream_record_marker(xbufp);
2598
 
 
 
 
 
2599	tailoff = (unsigned long)xbufp->tail[0].iov_base & ~PAGE_MASK;
2600	headoff = (unsigned long)xbufp->head[0].iov_base & ~PAGE_MASK;
2601	len = svc_send_common(sock, xbufp,
2602			      virt_to_page(xbufp->head[0].iov_base), headoff,
2603			      xbufp->tail[0].iov_base, tailoff);
2604
2605	if (len != xbufp->len) {
2606		printk(KERN_NOTICE "Error sending entire callback!\n");
2607		len = -EAGAIN;
2608	}
2609
2610	return len;
2611}
2612
2613/*
2614 * The send routine. Borrows from svc_send
2615 */
2616static int bc_send_request(struct rpc_task *task)
2617{
2618	struct rpc_rqst *req = task->tk_rqstp;
2619	struct svc_xprt	*xprt;
2620	int len;
2621
2622	dprintk("sending request with xid: %08x\n", ntohl(req->rq_xid));
2623	/*
2624	 * Get the server socket associated with this callback xprt
2625	 */
2626	xprt = req->rq_xprt->bc_xprt;
2627
2628	/*
2629	 * Grab the mutex to serialize data as the connection is shared
2630	 * with the fore channel
2631	 */
2632	if (!mutex_trylock(&xprt->xpt_mutex)) {
2633		rpc_sleep_on(&xprt->xpt_bc_pending, task, NULL);
2634		if (!mutex_trylock(&xprt->xpt_mutex))
2635			return -EAGAIN;
2636		rpc_wake_up_queued_task(&xprt->xpt_bc_pending, task);
2637	}
2638	if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2639		len = -ENOTCONN;
2640	else
2641		len = bc_sendto(req);
2642	mutex_unlock(&xprt->xpt_mutex);
2643
2644	if (len > 0)
2645		len = 0;
2646
2647	return len;
2648}
2649
2650/*
2651 * The close routine. Since this is client initiated, we do nothing
2652 */
2653
2654static void bc_close(struct rpc_xprt *xprt)
2655{
2656}
2657
2658/*
2659 * The xprt destroy routine. Again, because this connection is client
2660 * initiated, we do nothing
2661 */
2662
2663static void bc_destroy(struct rpc_xprt *xprt)
2664{
2665	dprintk("RPC:       bc_destroy xprt %p\n", xprt);
2666
2667	xs_xprt_free(xprt);
2668	module_put(THIS_MODULE);
2669}
2670
2671static struct rpc_xprt_ops xs_local_ops = {
2672	.reserve_xprt		= xprt_reserve_xprt,
2673	.release_xprt		= xs_tcp_release_xprt,
2674	.alloc_slot		= xprt_alloc_slot,
 
2675	.rpcbind		= xs_local_rpcbind,
2676	.set_port		= xs_local_set_port,
2677	.connect		= xs_local_connect,
2678	.buf_alloc		= rpc_malloc,
2679	.buf_free		= rpc_free,
 
2680	.send_request		= xs_local_send_request,
2681	.set_retrans_timeout	= xprt_set_retrans_timeout_def,
2682	.close			= xs_close,
2683	.destroy		= xs_destroy,
2684	.print_stats		= xs_local_print_stats,
2685	.enable_swap		= xs_enable_swap,
2686	.disable_swap		= xs_disable_swap,
2687};
2688
2689static struct rpc_xprt_ops xs_udp_ops = {
2690	.set_buffer_size	= xs_udp_set_buffer_size,
2691	.reserve_xprt		= xprt_reserve_xprt_cong,
2692	.release_xprt		= xprt_release_xprt_cong,
2693	.alloc_slot		= xprt_alloc_slot,
 
2694	.rpcbind		= rpcb_getport_async,
2695	.set_port		= xs_set_port,
2696	.connect		= xs_connect,
2697	.buf_alloc		= rpc_malloc,
2698	.buf_free		= rpc_free,
2699	.send_request		= xs_udp_send_request,
2700	.set_retrans_timeout	= xprt_set_retrans_timeout_rtt,
2701	.timer			= xs_udp_timer,
2702	.release_request	= xprt_release_rqst_cong,
2703	.close			= xs_close,
2704	.destroy		= xs_destroy,
2705	.print_stats		= xs_udp_print_stats,
2706	.enable_swap		= xs_enable_swap,
2707	.disable_swap		= xs_disable_swap,
2708	.inject_disconnect	= xs_inject_disconnect,
2709};
2710
2711static struct rpc_xprt_ops xs_tcp_ops = {
2712	.reserve_xprt		= xprt_reserve_xprt,
2713	.release_xprt		= xs_tcp_release_xprt,
2714	.alloc_slot		= xprt_lock_and_alloc_slot,
 
2715	.rpcbind		= rpcb_getport_async,
2716	.set_port		= xs_set_port,
2717	.connect		= xs_connect,
2718	.buf_alloc		= rpc_malloc,
2719	.buf_free		= rpc_free,
 
2720	.send_request		= xs_tcp_send_request,
2721	.set_retrans_timeout	= xprt_set_retrans_timeout_def,
2722	.close			= xs_tcp_shutdown,
2723	.destroy		= xs_destroy,
 
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_up			= xs_tcp_bc_up,
2731	.bc_maxpayload		= xs_tcp_bc_maxpayload,
 
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 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	.buf_alloc		= bc_malloc,
2746	.buf_free		= bc_free,
2747	.send_request		= bc_send_request,
2748	.set_retrans_timeout	= xprt_set_retrans_timeout_def,
2749	.close			= bc_close,
2750	.destroy		= bc_destroy,
2751	.print_stats		= xs_tcp_print_stats,
2752	.enable_swap		= xs_enable_swap,
2753	.disable_swap		= xs_disable_swap,
2754	.inject_disconnect	= xs_inject_disconnect,
2755};
2756
2757static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2758{
2759	static const struct sockaddr_in sin = {
2760		.sin_family		= AF_INET,
2761		.sin_addr.s_addr	= htonl(INADDR_ANY),
2762	};
2763	static const struct sockaddr_in6 sin6 = {
2764		.sin6_family		= AF_INET6,
2765		.sin6_addr		= IN6ADDR_ANY_INIT,
2766	};
2767
2768	switch (family) {
2769	case AF_LOCAL:
2770		break;
2771	case AF_INET:
2772		memcpy(sap, &sin, sizeof(sin));
2773		break;
2774	case AF_INET6:
2775		memcpy(sap, &sin6, sizeof(sin6));
2776		break;
2777	default:
2778		dprintk("RPC:       %s: Bad address family\n", __func__);
2779		return -EAFNOSUPPORT;
2780	}
2781	return 0;
2782}
2783
2784static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2785				      unsigned int slot_table_size,
2786				      unsigned int max_slot_table_size)
2787{
2788	struct rpc_xprt *xprt;
2789	struct sock_xprt *new;
2790
2791	if (args->addrlen > sizeof(xprt->addr)) {
2792		dprintk("RPC:       xs_setup_xprt: address too large\n");
2793		return ERR_PTR(-EBADF);
2794	}
2795
2796	xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2797			max_slot_table_size);
2798	if (xprt == NULL) {
2799		dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2800				"rpc_xprt\n");
2801		return ERR_PTR(-ENOMEM);
2802	}
2803
2804	new = container_of(xprt, struct sock_xprt, xprt);
2805	mutex_init(&new->recv_mutex);
2806	memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2807	xprt->addrlen = args->addrlen;
2808	if (args->srcaddr)
2809		memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2810	else {
2811		int err;
2812		err = xs_init_anyaddr(args->dstaddr->sa_family,
2813					(struct sockaddr *)&new->srcaddr);
2814		if (err != 0) {
2815			xprt_free(xprt);
2816			return ERR_PTR(err);
2817		}
2818	}
2819
2820	return xprt;
2821}
2822
2823static const struct rpc_timeout xs_local_default_timeout = {
2824	.to_initval = 10 * HZ,
2825	.to_maxval = 10 * HZ,
2826	.to_retries = 2,
2827};
2828
2829/**
2830 * xs_setup_local - Set up transport to use an AF_LOCAL socket
2831 * @args: rpc transport creation arguments
2832 *
2833 * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2834 */
2835static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2836{
2837	struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2838	struct sock_xprt *transport;
2839	struct rpc_xprt *xprt;
2840	struct rpc_xprt *ret;
2841
2842	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2843			xprt_max_tcp_slot_table_entries);
2844	if (IS_ERR(xprt))
2845		return xprt;
2846	transport = container_of(xprt, struct sock_xprt, xprt);
2847
2848	xprt->prot = 0;
2849	xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2850	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2851
2852	xprt->bind_timeout = XS_BIND_TO;
2853	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2854	xprt->idle_timeout = XS_IDLE_DISC_TO;
2855
2856	xprt->ops = &xs_local_ops;
2857	xprt->timeout = &xs_local_default_timeout;
2858
2859	INIT_WORK(&transport->recv_worker, xs_local_data_receive_workfn);
2860	INIT_DELAYED_WORK(&transport->connect_worker,
2861			xs_dummy_setup_socket);
2862
2863	switch (sun->sun_family) {
2864	case AF_LOCAL:
2865		if (sun->sun_path[0] != '/') {
2866			dprintk("RPC:       bad AF_LOCAL address: %s\n",
2867					sun->sun_path);
2868			ret = ERR_PTR(-EINVAL);
2869			goto out_err;
2870		}
2871		xprt_set_bound(xprt);
2872		xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
2873		ret = ERR_PTR(xs_local_setup_socket(transport));
2874		if (ret)
2875			goto out_err;
2876		break;
2877	default:
2878		ret = ERR_PTR(-EAFNOSUPPORT);
2879		goto out_err;
2880	}
2881
2882	dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
2883			xprt->address_strings[RPC_DISPLAY_ADDR]);
2884
2885	if (try_module_get(THIS_MODULE))
2886		return xprt;
2887	ret = ERR_PTR(-EINVAL);
2888out_err:
2889	xs_xprt_free(xprt);
2890	return ret;
2891}
2892
2893static const struct rpc_timeout xs_udp_default_timeout = {
2894	.to_initval = 5 * HZ,
2895	.to_maxval = 30 * HZ,
2896	.to_increment = 5 * HZ,
2897	.to_retries = 5,
2898};
2899
2900/**
2901 * xs_setup_udp - Set up transport to use a UDP socket
2902 * @args: rpc transport creation arguments
2903 *
2904 */
2905static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2906{
2907	struct sockaddr *addr = args->dstaddr;
2908	struct rpc_xprt *xprt;
2909	struct sock_xprt *transport;
2910	struct rpc_xprt *ret;
2911
2912	xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2913			xprt_udp_slot_table_entries);
2914	if (IS_ERR(xprt))
2915		return xprt;
2916	transport = container_of(xprt, struct sock_xprt, xprt);
2917
2918	xprt->prot = IPPROTO_UDP;
2919	xprt->tsh_size = 0;
2920	/* XXX: header size can vary due to auth type, IPv6, etc. */
2921	xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2922
2923	xprt->bind_timeout = XS_BIND_TO;
2924	xprt->reestablish_timeout = XS_UDP_REEST_TO;
2925	xprt->idle_timeout = XS_IDLE_DISC_TO;
2926
2927	xprt->ops = &xs_udp_ops;
2928
2929	xprt->timeout = &xs_udp_default_timeout;
2930
2931	INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
 
2932	INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
2933
2934	switch (addr->sa_family) {
2935	case AF_INET:
2936		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2937			xprt_set_bound(xprt);
2938
2939		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2940		break;
2941	case AF_INET6:
2942		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2943			xprt_set_bound(xprt);
2944
2945		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2946		break;
2947	default:
2948		ret = ERR_PTR(-EAFNOSUPPORT);
2949		goto out_err;
2950	}
2951
2952	if (xprt_bound(xprt))
2953		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2954				xprt->address_strings[RPC_DISPLAY_ADDR],
2955				xprt->address_strings[RPC_DISPLAY_PORT],
2956				xprt->address_strings[RPC_DISPLAY_PROTO]);
2957	else
2958		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2959				xprt->address_strings[RPC_DISPLAY_ADDR],
2960				xprt->address_strings[RPC_DISPLAY_PROTO]);
2961
2962	if (try_module_get(THIS_MODULE))
2963		return xprt;
2964	ret = ERR_PTR(-EINVAL);
2965out_err:
2966	xs_xprt_free(xprt);
2967	return ret;
2968}
2969
2970static const struct rpc_timeout xs_tcp_default_timeout = {
2971	.to_initval = 60 * HZ,
2972	.to_maxval = 60 * HZ,
2973	.to_retries = 2,
2974};
2975
2976/**
2977 * xs_setup_tcp - Set up transport to use a TCP socket
2978 * @args: rpc transport creation arguments
2979 *
2980 */
2981static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2982{
2983	struct sockaddr *addr = args->dstaddr;
2984	struct rpc_xprt *xprt;
2985	struct sock_xprt *transport;
2986	struct rpc_xprt *ret;
2987	unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
2988
2989	if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
2990		max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
2991
2992	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2993			max_slot_table_size);
2994	if (IS_ERR(xprt))
2995		return xprt;
2996	transport = container_of(xprt, struct sock_xprt, xprt);
2997
2998	xprt->prot = IPPROTO_TCP;
2999	xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
3000	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3001
3002	xprt->bind_timeout = XS_BIND_TO;
3003	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
3004	xprt->idle_timeout = XS_IDLE_DISC_TO;
3005
3006	xprt->ops = &xs_tcp_ops;
3007	xprt->timeout = &xs_tcp_default_timeout;
3008
3009	xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
 
 
3010
3011	INIT_WORK(&transport->recv_worker, xs_tcp_data_receive_workfn);
 
3012	INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
3013
3014	switch (addr->sa_family) {
3015	case AF_INET:
3016		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3017			xprt_set_bound(xprt);
3018
3019		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
3020		break;
3021	case AF_INET6:
3022		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3023			xprt_set_bound(xprt);
3024
3025		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
3026		break;
3027	default:
3028		ret = ERR_PTR(-EAFNOSUPPORT);
3029		goto out_err;
3030	}
3031
3032	if (xprt_bound(xprt))
3033		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3034				xprt->address_strings[RPC_DISPLAY_ADDR],
3035				xprt->address_strings[RPC_DISPLAY_PORT],
3036				xprt->address_strings[RPC_DISPLAY_PROTO]);
3037	else
3038		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3039				xprt->address_strings[RPC_DISPLAY_ADDR],
3040				xprt->address_strings[RPC_DISPLAY_PROTO]);
3041
3042	if (try_module_get(THIS_MODULE))
3043		return xprt;
3044	ret = ERR_PTR(-EINVAL);
3045out_err:
3046	xs_xprt_free(xprt);
3047	return ret;
3048}
3049
3050/**
3051 * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
3052 * @args: rpc transport creation arguments
3053 *
3054 */
3055static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
3056{
3057	struct sockaddr *addr = args->dstaddr;
3058	struct rpc_xprt *xprt;
3059	struct sock_xprt *transport;
3060	struct svc_sock *bc_sock;
3061	struct rpc_xprt *ret;
3062
3063	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3064			xprt_tcp_slot_table_entries);
3065	if (IS_ERR(xprt))
3066		return xprt;
3067	transport = container_of(xprt, struct sock_xprt, xprt);
3068
3069	xprt->prot = IPPROTO_TCP;
3070	xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
3071	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3072	xprt->timeout = &xs_tcp_default_timeout;
3073
3074	/* backchannel */
3075	xprt_set_bound(xprt);
3076	xprt->bind_timeout = 0;
3077	xprt->reestablish_timeout = 0;
3078	xprt->idle_timeout = 0;
3079
3080	xprt->ops = &bc_tcp_ops;
3081
3082	switch (addr->sa_family) {
3083	case AF_INET:
3084		xs_format_peer_addresses(xprt, "tcp",
3085					 RPCBIND_NETID_TCP);
3086		break;
3087	case AF_INET6:
3088		xs_format_peer_addresses(xprt, "tcp",
3089				   RPCBIND_NETID_TCP6);
3090		break;
3091	default:
3092		ret = ERR_PTR(-EAFNOSUPPORT);
3093		goto out_err;
3094	}
3095
3096	dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3097			xprt->address_strings[RPC_DISPLAY_ADDR],
3098			xprt->address_strings[RPC_DISPLAY_PORT],
3099			xprt->address_strings[RPC_DISPLAY_PROTO]);
3100
3101	/*
3102	 * Once we've associated a backchannel xprt with a connection,
3103	 * we want to keep it around as long as the connection lasts,
3104	 * in case we need to start using it for a backchannel again;
3105	 * this reference won't be dropped until bc_xprt is destroyed.
3106	 */
3107	xprt_get(xprt);
3108	args->bc_xprt->xpt_bc_xprt = xprt;
3109	xprt->bc_xprt = args->bc_xprt;
3110	bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3111	transport->sock = bc_sock->sk_sock;
3112	transport->inet = bc_sock->sk_sk;
3113
3114	/*
3115	 * Since we don't want connections for the backchannel, we set
3116	 * the xprt status to connected
3117	 */
3118	xprt_set_connected(xprt);
3119
3120	if (try_module_get(THIS_MODULE))
3121		return xprt;
3122
3123	args->bc_xprt->xpt_bc_xprt = NULL;
3124	args->bc_xprt->xpt_bc_xps = NULL;
3125	xprt_put(xprt);
3126	ret = ERR_PTR(-EINVAL);
3127out_err:
3128	xs_xprt_free(xprt);
3129	return ret;
3130}
3131
3132static struct xprt_class	xs_local_transport = {
3133	.list		= LIST_HEAD_INIT(xs_local_transport.list),
3134	.name		= "named UNIX socket",
3135	.owner		= THIS_MODULE,
3136	.ident		= XPRT_TRANSPORT_LOCAL,
3137	.setup		= xs_setup_local,
3138};
3139
3140static struct xprt_class	xs_udp_transport = {
3141	.list		= LIST_HEAD_INIT(xs_udp_transport.list),
3142	.name		= "udp",
3143	.owner		= THIS_MODULE,
3144	.ident		= XPRT_TRANSPORT_UDP,
3145	.setup		= xs_setup_udp,
3146};
3147
3148static struct xprt_class	xs_tcp_transport = {
3149	.list		= LIST_HEAD_INIT(xs_tcp_transport.list),
3150	.name		= "tcp",
3151	.owner		= THIS_MODULE,
3152	.ident		= XPRT_TRANSPORT_TCP,
3153	.setup		= xs_setup_tcp,
3154};
3155
3156static struct xprt_class	xs_bc_tcp_transport = {
3157	.list		= LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3158	.name		= "tcp NFSv4.1 backchannel",
3159	.owner		= THIS_MODULE,
3160	.ident		= XPRT_TRANSPORT_BC_TCP,
3161	.setup		= xs_setup_bc_tcp,
3162};
3163
3164/**
3165 * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3166 *
3167 */
3168int init_socket_xprt(void)
3169{
3170#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3171	if (!sunrpc_table_header)
3172		sunrpc_table_header = register_sysctl_table(sunrpc_table);
3173#endif
3174
3175	xprt_register_transport(&xs_local_transport);
3176	xprt_register_transport(&xs_udp_transport);
3177	xprt_register_transport(&xs_tcp_transport);
3178	xprt_register_transport(&xs_bc_tcp_transport);
3179
3180	return 0;
3181}
3182
3183/**
3184 * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3185 *
3186 */
3187void cleanup_socket_xprt(void)
3188{
3189#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3190	if (sunrpc_table_header) {
3191		unregister_sysctl_table(sunrpc_table_header);
3192		sunrpc_table_header = NULL;
3193	}
3194#endif
3195
3196	xprt_unregister_transport(&xs_local_transport);
3197	xprt_unregister_transport(&xs_udp_transport);
3198	xprt_unregister_transport(&xs_tcp_transport);
3199	xprt_unregister_transport(&xs_bc_tcp_transport);
3200}
3201
3202static int param_set_uint_minmax(const char *val,
3203		const struct kernel_param *kp,
3204		unsigned int min, unsigned int max)
3205{
3206	unsigned int num;
3207	int ret;
3208
3209	if (!val)
3210		return -EINVAL;
3211	ret = kstrtouint(val, 0, &num);
3212	if (ret == -EINVAL || num < min || num > max)
 
 
3213		return -EINVAL;
3214	*((unsigned int *)kp->arg) = num;
3215	return 0;
3216}
3217
3218static int param_set_portnr(const char *val, const struct kernel_param *kp)
3219{
3220	if (kp->arg == &xprt_min_resvport)
3221		return param_set_uint_minmax(val, kp,
3222			RPC_MIN_RESVPORT,
3223			xprt_max_resvport);
3224	return param_set_uint_minmax(val, kp,
3225			xprt_min_resvport,
3226			RPC_MAX_RESVPORT);
3227}
3228
3229static const struct kernel_param_ops param_ops_portnr = {
3230	.set = param_set_portnr,
3231	.get = param_get_uint,
3232};
3233
3234#define param_check_portnr(name, p) \
3235	__param_check(name, p, unsigned int);
3236
3237module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3238module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3239
3240static int param_set_slot_table_size(const char *val,
3241				     const struct kernel_param *kp)
3242{
3243	return param_set_uint_minmax(val, kp,
3244			RPC_MIN_SLOT_TABLE,
3245			RPC_MAX_SLOT_TABLE);
3246}
3247
3248static const struct kernel_param_ops param_ops_slot_table_size = {
3249	.set = param_set_slot_table_size,
3250	.get = param_get_uint,
3251};
3252
3253#define param_check_slot_table_size(name, p) \
3254	__param_check(name, p, unsigned int);
3255
3256static int param_set_max_slot_table_size(const char *val,
3257				     const struct kernel_param *kp)
3258{
3259	return param_set_uint_minmax(val, kp,
3260			RPC_MIN_SLOT_TABLE,
3261			RPC_MAX_SLOT_TABLE_LIMIT);
3262}
3263
3264static const struct kernel_param_ops param_ops_max_slot_table_size = {
3265	.set = param_set_max_slot_table_size,
3266	.get = param_get_uint,
3267};
3268
3269#define param_check_max_slot_table_size(name, p) \
3270	__param_check(name, p, unsigned int);
3271
3272module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3273		   slot_table_size, 0644);
3274module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3275		   max_slot_table_size, 0644);
3276module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3277		   slot_table_size, 0644);
3278