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