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v5.4
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * linux/net/sunrpc/svcsock.c
   4 *
   5 * These are the RPC server socket internals.
   6 *
   7 * The server scheduling algorithm does not always distribute the load
   8 * evenly when servicing a single client. May need to modify the
   9 * svc_xprt_enqueue procedure...
  10 *
  11 * TCP support is largely untested and may be a little slow. The problem
  12 * is that we currently do two separate recvfrom's, one for the 4-byte
  13 * record length, and the second for the actual record. This could possibly
  14 * be improved by always reading a minimum size of around 100 bytes and
  15 * tucking any superfluous bytes away in a temporary store. Still, that
  16 * leaves write requests out in the rain. An alternative may be to peek at
  17 * the first skb in the queue, and if it matches the next TCP sequence
  18 * number, to extract the record marker. Yuck.
  19 *
  20 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
  21 */
  22
  23#include <linux/kernel.h>
  24#include <linux/sched.h>
  25#include <linux/module.h>
  26#include <linux/errno.h>
  27#include <linux/fcntl.h>
  28#include <linux/net.h>
  29#include <linux/in.h>
  30#include <linux/inet.h>
  31#include <linux/udp.h>
  32#include <linux/tcp.h>
  33#include <linux/unistd.h>
  34#include <linux/slab.h>
  35#include <linux/netdevice.h>
  36#include <linux/skbuff.h>
  37#include <linux/file.h>
  38#include <linux/freezer.h>
  39#include <net/sock.h>
  40#include <net/checksum.h>
  41#include <net/ip.h>
  42#include <net/ipv6.h>
  43#include <net/udp.h>
  44#include <net/tcp.h>
  45#include <net/tcp_states.h>
  46#include <linux/uaccess.h>
  47#include <asm/ioctls.h>
  48#include <trace/events/skb.h>
  49
  50#include <linux/sunrpc/types.h>
  51#include <linux/sunrpc/clnt.h>
  52#include <linux/sunrpc/xdr.h>
  53#include <linux/sunrpc/msg_prot.h>
  54#include <linux/sunrpc/svcsock.h>
  55#include <linux/sunrpc/stats.h>
  56#include <linux/sunrpc/xprt.h>
  57
  58#include "sunrpc.h"
  59
  60#define RPCDBG_FACILITY	RPCDBG_SVCXPRT
  61
  62
  63static struct svc_sock *svc_setup_socket(struct svc_serv *, struct socket *,
  64					 int flags);
 
  65static int		svc_udp_recvfrom(struct svc_rqst *);
  66static int		svc_udp_sendto(struct svc_rqst *);
  67static void		svc_sock_detach(struct svc_xprt *);
  68static void		svc_tcp_sock_detach(struct svc_xprt *);
  69static void		svc_sock_free(struct svc_xprt *);
  70
  71static struct svc_xprt *svc_create_socket(struct svc_serv *, int,
  72					  struct net *, struct sockaddr *,
  73					  int, int);
 
 
 
 
 
 
 
  74#ifdef CONFIG_DEBUG_LOCK_ALLOC
  75static struct lock_class_key svc_key[2];
  76static struct lock_class_key svc_slock_key[2];
  77
  78static void svc_reclassify_socket(struct socket *sock)
  79{
  80	struct sock *sk = sock->sk;
  81
  82	if (WARN_ON_ONCE(!sock_allow_reclassification(sk)))
 
  83		return;
  84
  85	switch (sk->sk_family) {
  86	case AF_INET:
  87		sock_lock_init_class_and_name(sk, "slock-AF_INET-NFSD",
  88					      &svc_slock_key[0],
  89					      "sk_xprt.xpt_lock-AF_INET-NFSD",
  90					      &svc_key[0]);
  91		break;
  92
  93	case AF_INET6:
  94		sock_lock_init_class_and_name(sk, "slock-AF_INET6-NFSD",
  95					      &svc_slock_key[1],
  96					      "sk_xprt.xpt_lock-AF_INET6-NFSD",
  97					      &svc_key[1]);
  98		break;
  99
 100	default:
 101		BUG();
 102	}
 103}
 104#else
 105static void svc_reclassify_socket(struct socket *sock)
 106{
 107}
 108#endif
 109
 110/*
 111 * Release an skbuff after use
 112 */
 113static void svc_release_skb(struct svc_rqst *rqstp)
 114{
 115	struct sk_buff *skb = rqstp->rq_xprt_ctxt;
 116
 117	if (skb) {
 118		struct svc_sock *svsk =
 119			container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 120		rqstp->rq_xprt_ctxt = NULL;
 121
 122		dprintk("svc: service %p, releasing skb %p\n", rqstp, skb);
 123		skb_free_datagram_locked(svsk->sk_sk, skb);
 124	}
 125}
 126
 127static void svc_release_udp_skb(struct svc_rqst *rqstp)
 128{
 129	struct sk_buff *skb = rqstp->rq_xprt_ctxt;
 130
 131	if (skb) {
 132		rqstp->rq_xprt_ctxt = NULL;
 133
 134		dprintk("svc: service %p, releasing skb %p\n", rqstp, skb);
 135		consume_skb(skb);
 136	}
 137}
 138
 139union svc_pktinfo_u {
 140	struct in_pktinfo pkti;
 141	struct in6_pktinfo pkti6;
 142};
 143#define SVC_PKTINFO_SPACE \
 144	CMSG_SPACE(sizeof(union svc_pktinfo_u))
 145
 146static void svc_set_cmsg_data(struct svc_rqst *rqstp, struct cmsghdr *cmh)
 147{
 148	struct svc_sock *svsk =
 149		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 150	switch (svsk->sk_sk->sk_family) {
 151	case AF_INET: {
 152			struct in_pktinfo *pki = CMSG_DATA(cmh);
 153
 154			cmh->cmsg_level = SOL_IP;
 155			cmh->cmsg_type = IP_PKTINFO;
 156			pki->ipi_ifindex = 0;
 157			pki->ipi_spec_dst.s_addr =
 158				 svc_daddr_in(rqstp)->sin_addr.s_addr;
 159			cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
 160		}
 161		break;
 162
 163	case AF_INET6: {
 164			struct in6_pktinfo *pki = CMSG_DATA(cmh);
 165			struct sockaddr_in6 *daddr = svc_daddr_in6(rqstp);
 166
 167			cmh->cmsg_level = SOL_IPV6;
 168			cmh->cmsg_type = IPV6_PKTINFO;
 169			pki->ipi6_ifindex = daddr->sin6_scope_id;
 170			pki->ipi6_addr = daddr->sin6_addr;
 171			cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
 172		}
 173		break;
 174	}
 175}
 176
 177/*
 178 * send routine intended to be shared by the fore- and back-channel
 179 */
 180int svc_send_common(struct socket *sock, struct xdr_buf *xdr,
 181		    struct page *headpage, unsigned long headoffset,
 182		    struct page *tailpage, unsigned long tailoffset)
 183{
 184	int		result;
 185	int		size;
 186	struct page	**ppage = xdr->pages;
 187	size_t		base = xdr->page_base;
 188	unsigned int	pglen = xdr->page_len;
 189	unsigned int	flags = MSG_MORE | MSG_SENDPAGE_NOTLAST;
 190	int		slen;
 191	int		len = 0;
 192
 193	slen = xdr->len;
 194
 195	/* send head */
 196	if (slen == xdr->head[0].iov_len)
 197		flags = 0;
 198	len = kernel_sendpage(sock, headpage, headoffset,
 199				  xdr->head[0].iov_len, flags);
 200	if (len != xdr->head[0].iov_len)
 201		goto out;
 202	slen -= xdr->head[0].iov_len;
 203	if (slen == 0)
 204		goto out;
 205
 206	/* send page data */
 207	size = PAGE_SIZE - base < pglen ? PAGE_SIZE - base : pglen;
 208	while (pglen > 0) {
 209		if (slen == size)
 210			flags = 0;
 211		result = kernel_sendpage(sock, *ppage, base, size, flags);
 212		if (result > 0)
 213			len += result;
 214		if (result != size)
 215			goto out;
 216		slen -= size;
 217		pglen -= size;
 218		size = PAGE_SIZE < pglen ? PAGE_SIZE : pglen;
 219		base = 0;
 220		ppage++;
 221	}
 222
 223	/* send tail */
 224	if (xdr->tail[0].iov_len) {
 225		result = kernel_sendpage(sock, tailpage, tailoffset,
 226				   xdr->tail[0].iov_len, 0);
 227		if (result > 0)
 228			len += result;
 229	}
 230
 231out:
 232	return len;
 233}
 234
 235
 236/*
 237 * Generic sendto routine
 238 */
 239static int svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr)
 240{
 241	struct svc_sock	*svsk =
 242		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 243	struct socket	*sock = svsk->sk_sock;
 244	union {
 245		struct cmsghdr	hdr;
 246		long		all[SVC_PKTINFO_SPACE / sizeof(long)];
 247	} buffer;
 248	struct cmsghdr *cmh = &buffer.hdr;
 249	int		len = 0;
 250	unsigned long tailoff;
 251	unsigned long headoff;
 252	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
 253
 254	if (rqstp->rq_prot == IPPROTO_UDP) {
 255		struct msghdr msg = {
 256			.msg_name	= &rqstp->rq_addr,
 257			.msg_namelen	= rqstp->rq_addrlen,
 258			.msg_control	= cmh,
 259			.msg_controllen	= sizeof(buffer),
 260			.msg_flags	= MSG_MORE,
 261		};
 262
 263		svc_set_cmsg_data(rqstp, cmh);
 264
 265		if (sock_sendmsg(sock, &msg) < 0)
 266			goto out;
 267	}
 268
 269	tailoff = ((unsigned long)xdr->tail[0].iov_base) & (PAGE_SIZE-1);
 270	headoff = 0;
 271	len = svc_send_common(sock, xdr, rqstp->rq_respages[0], headoff,
 272			       rqstp->rq_respages[0], tailoff);
 273
 274out:
 275	dprintk("svc: socket %p sendto([%p %zu... ], %d) = %d (addr %s)\n",
 276		svsk, xdr->head[0].iov_base, xdr->head[0].iov_len,
 277		xdr->len, len, svc_print_addr(rqstp, buf, sizeof(buf)));
 278
 279	return len;
 280}
 281
 282/*
 283 * Report socket names for nfsdfs
 284 */
 285static int svc_one_sock_name(struct svc_sock *svsk, char *buf, int remaining)
 286{
 287	const struct sock *sk = svsk->sk_sk;
 288	const char *proto_name = sk->sk_protocol == IPPROTO_UDP ?
 289							"udp" : "tcp";
 290	int len;
 291
 292	switch (sk->sk_family) {
 293	case PF_INET:
 294		len = snprintf(buf, remaining, "ipv4 %s %pI4 %d\n",
 295				proto_name,
 296				&inet_sk(sk)->inet_rcv_saddr,
 297				inet_sk(sk)->inet_num);
 298		break;
 299#if IS_ENABLED(CONFIG_IPV6)
 300	case PF_INET6:
 301		len = snprintf(buf, remaining, "ipv6 %s %pI6 %d\n",
 302				proto_name,
 303				&sk->sk_v6_rcv_saddr,
 304				inet_sk(sk)->inet_num);
 305		break;
 306#endif
 307	default:
 308		len = snprintf(buf, remaining, "*unknown-%d*\n",
 309				sk->sk_family);
 310	}
 311
 312	if (len >= remaining) {
 313		*buf = '\0';
 314		return -ENAMETOOLONG;
 315	}
 316	return len;
 317}
 318
 319/*
 320 * Generic recvfrom routine.
 321 */
 322static ssize_t svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov,
 323			    unsigned int nr, size_t buflen, unsigned int base)
 324{
 325	struct svc_sock *svsk =
 326		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 327	struct msghdr msg = { NULL };
 328	ssize_t len;
 
 
 329
 330	rqstp->rq_xprt_hlen = 0;
 331
 332	clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 333	iov_iter_kvec(&msg.msg_iter, READ, iov, nr, buflen);
 334	if (base != 0) {
 335		iov_iter_advance(&msg.msg_iter, base);
 336		buflen -= base;
 337	}
 338	len = sock_recvmsg(svsk->sk_sock, &msg, MSG_DONTWAIT);
 339	/* If we read a full record, then assume there may be more
 340	 * data to read (stream based sockets only!)
 341	 */
 342	if (len == buflen)
 343		set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 344
 345	dprintk("svc: socket %p recvfrom(%p, %zu) = %zd\n",
 346		svsk, iov[0].iov_base, iov[0].iov_len, len);
 347	return len;
 348}
 349
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 350/*
 351 * Set socket snd and rcv buffer lengths
 352 */
 353static void svc_sock_setbufsize(struct svc_sock *svsk, unsigned int nreqs)
 
 354{
 355	unsigned int max_mesg = svsk->sk_xprt.xpt_server->sv_max_mesg;
 356	struct socket *sock = svsk->sk_sock;
 357
 358	nreqs = min(nreqs, INT_MAX / 2 / max_mesg);
 359
 
 
 
 
 
 
 
 
 360	lock_sock(sock->sk);
 361	sock->sk->sk_sndbuf = nreqs * max_mesg * 2;
 362	sock->sk->sk_rcvbuf = nreqs * max_mesg * 2;
 363	sock->sk->sk_write_space(sock->sk);
 364	release_sock(sock->sk);
 
 365}
 366
 367static void svc_sock_secure_port(struct svc_rqst *rqstp)
 368{
 369	if (svc_port_is_privileged(svc_addr(rqstp)))
 370		set_bit(RQ_SECURE, &rqstp->rq_flags);
 371	else
 372		clear_bit(RQ_SECURE, &rqstp->rq_flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 373}
 374
 375/*
 376 * INET callback when data has been received on the socket.
 377 */
 378static void svc_data_ready(struct sock *sk)
 379{
 380	struct svc_sock	*svsk = (struct svc_sock *)sk->sk_user_data;
 
 381
 382	if (svsk) {
 383		dprintk("svc: socket %p(inet %p), busy=%d\n",
 384			svsk, sk,
 385			test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags));
 386
 387		/* Refer to svc_setup_socket() for details. */
 388		rmb();
 389		svsk->sk_odata(sk);
 390		if (!test_and_set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags))
 391			svc_xprt_enqueue(&svsk->sk_xprt);
 392	}
 
 
 393}
 394
 395/*
 396 * INET callback when space is newly available on the socket.
 397 */
 398static void svc_write_space(struct sock *sk)
 399{
 400	struct svc_sock	*svsk = (struct svc_sock *)(sk->sk_user_data);
 
 401
 402	if (svsk) {
 403		dprintk("svc: socket %p(inet %p), write_space busy=%d\n",
 404			svsk, sk, test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags));
 405
 406		/* Refer to svc_setup_socket() for details. */
 407		rmb();
 408		svsk->sk_owspace(sk);
 409		svc_xprt_enqueue(&svsk->sk_xprt);
 410	}
 
 
 
 
 
 
 411}
 412
 413static int svc_tcp_has_wspace(struct svc_xprt *xprt)
 414{
 415	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
 
 
 416
 417	if (test_bit(XPT_LISTENER, &xprt->xpt_flags))
 418		return 1;
 419	return !test_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
 
 
 
 
 
 
 420}
 421
 422static void svc_tcp_kill_temp_xprt(struct svc_xprt *xprt)
 423{
 424	struct svc_sock *svsk;
 425	struct socket *sock;
 426	struct linger no_linger = {
 427		.l_onoff = 1,
 428		.l_linger = 0,
 429	};
 430
 431	svsk = container_of(xprt, struct svc_sock, sk_xprt);
 432	sock = svsk->sk_sock;
 433	kernel_setsockopt(sock, SOL_SOCKET, SO_LINGER,
 434			  (char *)&no_linger, sizeof(no_linger));
 
 
 
 
 
 
 
 
 
 435}
 436
 437/*
 438 * See net/ipv6/ip_sockglue.c : ip_cmsg_recv_pktinfo
 439 */
 440static int svc_udp_get_dest_address4(struct svc_rqst *rqstp,
 441				     struct cmsghdr *cmh)
 442{
 443	struct in_pktinfo *pki = CMSG_DATA(cmh);
 444	struct sockaddr_in *daddr = svc_daddr_in(rqstp);
 445
 446	if (cmh->cmsg_type != IP_PKTINFO)
 447		return 0;
 448
 449	daddr->sin_family = AF_INET;
 450	daddr->sin_addr.s_addr = pki->ipi_spec_dst.s_addr;
 451	return 1;
 452}
 453
 454/*
 455 * See net/ipv6/datagram.c : ip6_datagram_recv_ctl
 456 */
 457static int svc_udp_get_dest_address6(struct svc_rqst *rqstp,
 458				     struct cmsghdr *cmh)
 459{
 460	struct in6_pktinfo *pki = CMSG_DATA(cmh);
 461	struct sockaddr_in6 *daddr = svc_daddr_in6(rqstp);
 462
 463	if (cmh->cmsg_type != IPV6_PKTINFO)
 464		return 0;
 465
 466	daddr->sin6_family = AF_INET6;
 467	daddr->sin6_addr = pki->ipi6_addr;
 468	daddr->sin6_scope_id = pki->ipi6_ifindex;
 469	return 1;
 470}
 471
 472/*
 473 * Copy the UDP datagram's destination address to the rqstp structure.
 474 * The 'destination' address in this case is the address to which the
 475 * peer sent the datagram, i.e. our local address. For multihomed
 476 * hosts, this can change from msg to msg. Note that only the IP
 477 * address changes, the port number should remain the same.
 478 */
 479static int svc_udp_get_dest_address(struct svc_rqst *rqstp,
 480				    struct cmsghdr *cmh)
 481{
 482	switch (cmh->cmsg_level) {
 483	case SOL_IP:
 484		return svc_udp_get_dest_address4(rqstp, cmh);
 485	case SOL_IPV6:
 486		return svc_udp_get_dest_address6(rqstp, cmh);
 487	}
 488
 489	return 0;
 490}
 491
 492/*
 493 * Receive a datagram from a UDP socket.
 494 */
 495static int svc_udp_recvfrom(struct svc_rqst *rqstp)
 496{
 497	struct svc_sock	*svsk =
 498		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 499	struct svc_serv	*serv = svsk->sk_xprt.xpt_server;
 500	struct sk_buff	*skb;
 501	union {
 502		struct cmsghdr	hdr;
 503		long		all[SVC_PKTINFO_SPACE / sizeof(long)];
 504	} buffer;
 505	struct cmsghdr *cmh = &buffer.hdr;
 506	struct msghdr msg = {
 507		.msg_name = svc_addr(rqstp),
 508		.msg_control = cmh,
 509		.msg_controllen = sizeof(buffer),
 510		.msg_flags = MSG_DONTWAIT,
 511	};
 512	size_t len;
 513	int err;
 514
 515	if (test_and_clear_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags))
 516	    /* udp sockets need large rcvbuf as all pending
 517	     * requests are still in that buffer.  sndbuf must
 518	     * also be large enough that there is enough space
 519	     * for one reply per thread.  We count all threads
 520	     * rather than threads in a particular pool, which
 521	     * provides an upper bound on the number of threads
 522	     * which will access the socket.
 523	     */
 524	    svc_sock_setbufsize(svsk, serv->sv_nrthreads + 3);
 
 
 525
 526	clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 527	skb = NULL;
 528	err = kernel_recvmsg(svsk->sk_sock, &msg, NULL,
 529			     0, 0, MSG_PEEK | MSG_DONTWAIT);
 530	if (err >= 0)
 531		skb = skb_recv_udp(svsk->sk_sk, 0, 1, &err);
 532
 533	if (skb == NULL) {
 534		if (err != -EAGAIN) {
 535			/* possibly an icmp error */
 536			dprintk("svc: recvfrom returned error %d\n", -err);
 537			set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 538		}
 539		return 0;
 540	}
 541	len = svc_addr_len(svc_addr(rqstp));
 542	rqstp->rq_addrlen = len;
 543	if (skb->tstamp == 0) {
 544		skb->tstamp = ktime_get_real();
 545		/* Don't enable netstamp, sunrpc doesn't
 546		   need that much accuracy */
 547	}
 548	sock_write_timestamp(svsk->sk_sk, skb->tstamp);
 549	set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); /* there may be more data... */
 550
 551	len  = skb->len;
 552	rqstp->rq_arg.len = len;
 553
 554	rqstp->rq_prot = IPPROTO_UDP;
 555
 556	if (!svc_udp_get_dest_address(rqstp, cmh)) {
 557		net_warn_ratelimited("svc: received unknown control message %d/%d; dropping RPC reply datagram\n",
 558				     cmh->cmsg_level, cmh->cmsg_type);
 559		goto out_free;
 560	}
 561	rqstp->rq_daddrlen = svc_addr_len(svc_daddr(rqstp));
 562
 563	if (skb_is_nonlinear(skb)) {
 564		/* we have to copy */
 565		local_bh_disable();
 566		if (csum_partial_copy_to_xdr(&rqstp->rq_arg, skb)) {
 567			local_bh_enable();
 568			/* checksum error */
 569			goto out_free;
 570		}
 571		local_bh_enable();
 572		consume_skb(skb);
 573	} else {
 574		/* we can use it in-place */
 575		rqstp->rq_arg.head[0].iov_base = skb->data;
 
 576		rqstp->rq_arg.head[0].iov_len = len;
 577		if (skb_checksum_complete(skb))
 578			goto out_free;
 579		rqstp->rq_xprt_ctxt = skb;
 580	}
 581
 582	rqstp->rq_arg.page_base = 0;
 583	if (len <= rqstp->rq_arg.head[0].iov_len) {
 584		rqstp->rq_arg.head[0].iov_len = len;
 585		rqstp->rq_arg.page_len = 0;
 586		rqstp->rq_respages = rqstp->rq_pages+1;
 587	} else {
 588		rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len;
 589		rqstp->rq_respages = rqstp->rq_pages + 1 +
 590			DIV_ROUND_UP(rqstp->rq_arg.page_len, PAGE_SIZE);
 591	}
 592	rqstp->rq_next_page = rqstp->rq_respages+1;
 593
 594	if (serv->sv_stats)
 595		serv->sv_stats->netudpcnt++;
 596
 597	return len;
 598out_free:
 599	kfree_skb(skb);
 
 600	return 0;
 601}
 602
 603static int
 604svc_udp_sendto(struct svc_rqst *rqstp)
 605{
 606	int		error;
 607
 608	error = svc_sendto(rqstp, &rqstp->rq_res);
 609	if (error == -ECONNREFUSED)
 610		/* ICMP error on earlier request. */
 611		error = svc_sendto(rqstp, &rqstp->rq_res);
 612
 613	return error;
 614}
 615
 
 
 
 
 616static int svc_udp_has_wspace(struct svc_xprt *xprt)
 617{
 618	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
 619	struct svc_serv	*serv = xprt->xpt_server;
 620	unsigned long required;
 621
 622	/*
 623	 * Set the SOCK_NOSPACE flag before checking the available
 624	 * sock space.
 625	 */
 626	set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
 627	required = atomic_read(&svsk->sk_xprt.xpt_reserved) + serv->sv_max_mesg;
 628	if (required*2 > sock_wspace(svsk->sk_sk))
 629		return 0;
 630	clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
 631	return 1;
 632}
 633
 634static struct svc_xprt *svc_udp_accept(struct svc_xprt *xprt)
 635{
 636	BUG();
 637	return NULL;
 638}
 639
 640static void svc_udp_kill_temp_xprt(struct svc_xprt *xprt)
 641{
 642}
 643
 644static struct svc_xprt *svc_udp_create(struct svc_serv *serv,
 645				       struct net *net,
 646				       struct sockaddr *sa, int salen,
 647				       int flags)
 648{
 649	return svc_create_socket(serv, IPPROTO_UDP, net, sa, salen, flags);
 650}
 651
 652static const struct svc_xprt_ops svc_udp_ops = {
 653	.xpo_create = svc_udp_create,
 654	.xpo_recvfrom = svc_udp_recvfrom,
 655	.xpo_sendto = svc_udp_sendto,
 656	.xpo_release_rqst = svc_release_udp_skb,
 657	.xpo_detach = svc_sock_detach,
 658	.xpo_free = svc_sock_free,
 
 659	.xpo_has_wspace = svc_udp_has_wspace,
 660	.xpo_accept = svc_udp_accept,
 661	.xpo_secure_port = svc_sock_secure_port,
 662	.xpo_kill_temp_xprt = svc_udp_kill_temp_xprt,
 663};
 664
 665static struct svc_xprt_class svc_udp_class = {
 666	.xcl_name = "udp",
 667	.xcl_owner = THIS_MODULE,
 668	.xcl_ops = &svc_udp_ops,
 669	.xcl_max_payload = RPCSVC_MAXPAYLOAD_UDP,
 670	.xcl_ident = XPRT_TRANSPORT_UDP,
 671};
 672
 673static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv)
 674{
 675	int err, level, optname, one = 1;
 676
 677	svc_xprt_init(sock_net(svsk->sk_sock->sk), &svc_udp_class,
 678		      &svsk->sk_xprt, serv);
 679	clear_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
 680	svsk->sk_sk->sk_data_ready = svc_data_ready;
 681	svsk->sk_sk->sk_write_space = svc_write_space;
 682
 683	/* initialise setting must have enough space to
 684	 * receive and respond to one request.
 685	 * svc_udp_recvfrom will re-adjust if necessary
 686	 */
 687	svc_sock_setbufsize(svsk, 3);
 
 
 688
 689	/* data might have come in before data_ready set up */
 690	set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 691	set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
 692
 693	/* make sure we get destination address info */
 694	switch (svsk->sk_sk->sk_family) {
 695	case AF_INET:
 696		level = SOL_IP;
 697		optname = IP_PKTINFO;
 698		break;
 699	case AF_INET6:
 700		level = SOL_IPV6;
 701		optname = IPV6_RECVPKTINFO;
 702		break;
 703	default:
 704		BUG();
 705	}
 706	err = kernel_setsockopt(svsk->sk_sock, level, optname,
 707					(char *)&one, sizeof(one));
 708	dprintk("svc: kernel_setsockopt returned %d\n", err);
 709}
 710
 711/*
 712 * A data_ready event on a listening socket means there's a connection
 713 * pending. Do not use state_change as a substitute for it.
 714 */
 715static void svc_tcp_listen_data_ready(struct sock *sk)
 716{
 717	struct svc_sock	*svsk = (struct svc_sock *)sk->sk_user_data;
 
 718
 719	dprintk("svc: socket %p TCP (listen) state change %d\n",
 720		sk, sk->sk_state);
 721
 722	if (svsk) {
 723		/* Refer to svc_setup_socket() for details. */
 724		rmb();
 725		svsk->sk_odata(sk);
 726	}
 727
 728	/*
 729	 * This callback may called twice when a new connection
 730	 * is established as a child socket inherits everything
 731	 * from a parent LISTEN socket.
 732	 * 1) data_ready method of the parent socket will be called
 733	 *    when one of child sockets become ESTABLISHED.
 734	 * 2) data_ready method of the child socket may be called
 735	 *    when it receives data before the socket is accepted.
 736	 * In case of 2, we should ignore it silently.
 737	 */
 738	if (sk->sk_state == TCP_LISTEN) {
 739		if (svsk) {
 740			set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
 741			svc_xprt_enqueue(&svsk->sk_xprt);
 742		} else
 743			printk("svc: socket %p: no user data\n", sk);
 744	}
 
 
 
 
 745}
 746
 747/*
 748 * A state change on a connected socket means it's dying or dead.
 749 */
 750static void svc_tcp_state_change(struct sock *sk)
 751{
 752	struct svc_sock	*svsk = (struct svc_sock *)sk->sk_user_data;
 
 753
 754	dprintk("svc: socket %p TCP (connected) state change %d (svsk %p)\n",
 755		sk, sk->sk_state, sk->sk_user_data);
 756
 757	if (!svsk)
 758		printk("svc: socket %p: no user data\n", sk);
 759	else {
 760		/* Refer to svc_setup_socket() for details. */
 761		rmb();
 762		svsk->sk_ostate(sk);
 763		if (sk->sk_state != TCP_ESTABLISHED) {
 764			set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
 765			svc_xprt_enqueue(&svsk->sk_xprt);
 766		}
 
 
 
 
 
 
 
 
 
 
 767	}
 
 
 768}
 769
 770/*
 771 * Accept a TCP connection
 772 */
 773static struct svc_xprt *svc_tcp_accept(struct svc_xprt *xprt)
 774{
 775	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
 776	struct sockaddr_storage addr;
 777	struct sockaddr	*sin = (struct sockaddr *) &addr;
 778	struct svc_serv	*serv = svsk->sk_xprt.xpt_server;
 779	struct socket	*sock = svsk->sk_sock;
 780	struct socket	*newsock;
 781	struct svc_sock	*newsvsk;
 782	int		err, slen;
 783	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
 784
 785	dprintk("svc: tcp_accept %p sock %p\n", svsk, sock);
 786	if (!sock)
 787		return NULL;
 788
 789	clear_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
 790	err = kernel_accept(sock, &newsock, O_NONBLOCK);
 791	if (err < 0) {
 792		if (err == -ENOMEM)
 793			printk(KERN_WARNING "%s: no more sockets!\n",
 794			       serv->sv_name);
 795		else if (err != -EAGAIN)
 796			net_warn_ratelimited("%s: accept failed (err %d)!\n",
 797					     serv->sv_name, -err);
 798		return NULL;
 799	}
 800	set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
 801
 802	err = kernel_getpeername(newsock, sin);
 803	if (err < 0) {
 804		net_warn_ratelimited("%s: peername failed (err %d)!\n",
 805				     serv->sv_name, -err);
 806		goto failed;		/* aborted connection or whatever */
 807	}
 808	slen = err;
 809
 810	/* Ideally, we would want to reject connections from unauthorized
 811	 * hosts here, but when we get encryption, the IP of the host won't
 812	 * tell us anything.  For now just warn about unpriv connections.
 813	 */
 814	if (!svc_port_is_privileged(sin)) {
 815		dprintk("%s: connect from unprivileged port: %s\n",
 816			serv->sv_name,
 817			__svc_print_addr(sin, buf, sizeof(buf)));
 818	}
 819	dprintk("%s: connect from %s\n", serv->sv_name,
 820		__svc_print_addr(sin, buf, sizeof(buf)));
 821
 822	/* Reset the inherited callbacks before calling svc_setup_socket */
 823	newsock->sk->sk_state_change = svsk->sk_ostate;
 824	newsock->sk->sk_data_ready = svsk->sk_odata;
 825	newsock->sk->sk_write_space = svsk->sk_owspace;
 826
 827	/* make sure that a write doesn't block forever when
 828	 * low on memory
 829	 */
 830	newsock->sk->sk_sndtimeo = HZ*30;
 831
 832	newsvsk = svc_setup_socket(serv, newsock,
 833				 (SVC_SOCK_ANONYMOUS | SVC_SOCK_TEMPORARY));
 834	if (IS_ERR(newsvsk))
 835		goto failed;
 836	svc_xprt_set_remote(&newsvsk->sk_xprt, sin, slen);
 837	err = kernel_getsockname(newsock, sin);
 838	slen = err;
 839	if (unlikely(err < 0)) {
 840		dprintk("svc_tcp_accept: kernel_getsockname error %d\n", -err);
 841		slen = offsetof(struct sockaddr, sa_data);
 842	}
 843	svc_xprt_set_local(&newsvsk->sk_xprt, sin, slen);
 844
 845	if (sock_is_loopback(newsock->sk))
 846		set_bit(XPT_LOCAL, &newsvsk->sk_xprt.xpt_flags);
 847	else
 848		clear_bit(XPT_LOCAL, &newsvsk->sk_xprt.xpt_flags);
 849	if (serv->sv_stats)
 850		serv->sv_stats->nettcpconn++;
 851
 852	return &newsvsk->sk_xprt;
 853
 854failed:
 855	sock_release(newsock);
 856	return NULL;
 857}
 858
 859static unsigned int svc_tcp_restore_pages(struct svc_sock *svsk, struct svc_rqst *rqstp)
 860{
 861	unsigned int i, len, npages;
 862
 863	if (svsk->sk_datalen == 0)
 864		return 0;
 865	len = svsk->sk_datalen;
 866	npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
 867	for (i = 0; i < npages; i++) {
 868		if (rqstp->rq_pages[i] != NULL)
 869			put_page(rqstp->rq_pages[i]);
 870		BUG_ON(svsk->sk_pages[i] == NULL);
 871		rqstp->rq_pages[i] = svsk->sk_pages[i];
 872		svsk->sk_pages[i] = NULL;
 873	}
 874	rqstp->rq_arg.head[0].iov_base = page_address(rqstp->rq_pages[0]);
 875	return len;
 876}
 877
 878static void svc_tcp_save_pages(struct svc_sock *svsk, struct svc_rqst *rqstp)
 879{
 880	unsigned int i, len, npages;
 881
 882	if (svsk->sk_datalen == 0)
 883		return;
 884	len = svsk->sk_datalen;
 885	npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
 886	for (i = 0; i < npages; i++) {
 887		svsk->sk_pages[i] = rqstp->rq_pages[i];
 888		rqstp->rq_pages[i] = NULL;
 889	}
 890}
 891
 892static void svc_tcp_clear_pages(struct svc_sock *svsk)
 893{
 894	unsigned int i, len, npages;
 895
 896	if (svsk->sk_datalen == 0)
 897		goto out;
 898	len = svsk->sk_datalen;
 899	npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
 900	for (i = 0; i < npages; i++) {
 901		if (svsk->sk_pages[i] == NULL) {
 902			WARN_ON_ONCE(1);
 903			continue;
 904		}
 905		put_page(svsk->sk_pages[i]);
 906		svsk->sk_pages[i] = NULL;
 907	}
 908out:
 909	svsk->sk_tcplen = 0;
 910	svsk->sk_datalen = 0;
 911}
 912
 913/*
 914 * Receive fragment record header.
 915 * If we haven't gotten the record length yet, get the next four bytes.
 916 */
 917static int svc_tcp_recv_record(struct svc_sock *svsk, struct svc_rqst *rqstp)
 918{
 919	struct svc_serv	*serv = svsk->sk_xprt.xpt_server;
 920	unsigned int want;
 921	int len;
 922
 923	if (svsk->sk_tcplen < sizeof(rpc_fraghdr)) {
 924		struct kvec	iov;
 925
 926		want = sizeof(rpc_fraghdr) - svsk->sk_tcplen;
 927		iov.iov_base = ((char *) &svsk->sk_reclen) + svsk->sk_tcplen;
 928		iov.iov_len  = want;
 929		len = svc_recvfrom(rqstp, &iov, 1, want, 0);
 930		if (len < 0)
 931			goto error;
 932		svsk->sk_tcplen += len;
 933
 934		if (len < want) {
 935			dprintk("svc: short recvfrom while reading record "
 936				"length (%d of %d)\n", len, want);
 937			return -EAGAIN;
 938		}
 939
 940		dprintk("svc: TCP record, %d bytes\n", svc_sock_reclen(svsk));
 941		if (svc_sock_reclen(svsk) + svsk->sk_datalen >
 942							serv->sv_max_mesg) {
 943			net_notice_ratelimited("RPC: fragment too large: %d\n",
 944					svc_sock_reclen(svsk));
 945			goto err_delete;
 946		}
 947	}
 948
 949	return svc_sock_reclen(svsk);
 950error:
 951	dprintk("RPC: TCP recv_record got %d\n", len);
 952	return len;
 953err_delete:
 954	set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
 955	return -EAGAIN;
 956}
 957
 958static int receive_cb_reply(struct svc_sock *svsk, struct svc_rqst *rqstp)
 959{
 960	struct rpc_xprt *bc_xprt = svsk->sk_xprt.xpt_bc_xprt;
 961	struct rpc_rqst *req = NULL;
 962	struct kvec *src, *dst;
 963	__be32 *p = (__be32 *)rqstp->rq_arg.head[0].iov_base;
 964	__be32 xid;
 965	__be32 calldir;
 966
 967	xid = *p++;
 968	calldir = *p;
 969
 970	if (!bc_xprt)
 971		return -EAGAIN;
 972	spin_lock(&bc_xprt->queue_lock);
 973	req = xprt_lookup_rqst(bc_xprt, xid);
 974	if (!req)
 975		goto unlock_notfound;
 976
 977	memcpy(&req->rq_private_buf, &req->rq_rcv_buf, sizeof(struct xdr_buf));
 978	/*
 979	 * XXX!: cheating for now!  Only copying HEAD.
 980	 * But we know this is good enough for now (in fact, for any
 981	 * callback reply in the forseeable future).
 982	 */
 983	dst = &req->rq_private_buf.head[0];
 984	src = &rqstp->rq_arg.head[0];
 985	if (dst->iov_len < src->iov_len)
 986		goto unlock_eagain; /* whatever; just giving up. */
 987	memcpy(dst->iov_base, src->iov_base, src->iov_len);
 988	xprt_complete_rqst(req->rq_task, rqstp->rq_arg.len);
 989	rqstp->rq_arg.len = 0;
 990	spin_unlock(&bc_xprt->queue_lock);
 991	return 0;
 992unlock_notfound:
 993	printk(KERN_NOTICE
 994		"%s: Got unrecognized reply: "
 995		"calldir 0x%x xpt_bc_xprt %p xid %08x\n",
 996		__func__, ntohl(calldir),
 997		bc_xprt, ntohl(xid));
 998unlock_eagain:
 999	spin_unlock(&bc_xprt->queue_lock);
1000	return -EAGAIN;
1001}
1002
1003static int copy_pages_to_kvecs(struct kvec *vec, struct page **pages, int len)
1004{
1005	int i = 0;
1006	int t = 0;
1007
1008	while (t < len) {
1009		vec[i].iov_base = page_address(pages[i]);
1010		vec[i].iov_len = PAGE_SIZE;
1011		i++;
1012		t += PAGE_SIZE;
1013	}
1014	return i;
1015}
1016
1017static void svc_tcp_fragment_received(struct svc_sock *svsk)
1018{
1019	/* If we have more data, signal svc_xprt_enqueue() to try again */
1020	dprintk("svc: TCP %s record (%d bytes)\n",
1021		svc_sock_final_rec(svsk) ? "final" : "nonfinal",
1022		svc_sock_reclen(svsk));
1023	svsk->sk_tcplen = 0;
1024	svsk->sk_reclen = 0;
1025}
1026
1027/*
1028 * Receive data from a TCP socket.
1029 */
1030static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
1031{
1032	struct svc_sock	*svsk =
1033		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
1034	struct svc_serv	*serv = svsk->sk_xprt.xpt_server;
1035	int		len;
1036	struct kvec *vec;
1037	unsigned int want, base;
1038	__be32 *p;
1039	__be32 calldir;
1040	int pnum;
1041
1042	dprintk("svc: tcp_recv %p data %d conn %d close %d\n",
1043		svsk, test_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags),
1044		test_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags),
1045		test_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags));
1046
1047	len = svc_tcp_recv_record(svsk, rqstp);
1048	if (len < 0)
1049		goto error;
1050
1051	base = svc_tcp_restore_pages(svsk, rqstp);
1052	want = svc_sock_reclen(svsk) - (svsk->sk_tcplen - sizeof(rpc_fraghdr));
1053
1054	vec = rqstp->rq_vec;
1055
1056	pnum = copy_pages_to_kvecs(&vec[0], &rqstp->rq_pages[0], base + want);
 
1057
1058	rqstp->rq_respages = &rqstp->rq_pages[pnum];
1059	rqstp->rq_next_page = rqstp->rq_respages + 1;
1060
1061	/* Now receive data */
1062	len = svc_recvfrom(rqstp, vec, pnum, base + want, base);
1063	if (len >= 0) {
1064		svsk->sk_tcplen += len;
1065		svsk->sk_datalen += len;
1066	}
1067	if (len != want || !svc_sock_final_rec(svsk)) {
1068		svc_tcp_save_pages(svsk, rqstp);
1069		if (len < 0 && len != -EAGAIN)
1070			goto err_delete;
1071		if (len == want)
1072			svc_tcp_fragment_received(svsk);
1073		else
1074			dprintk("svc: incomplete TCP record (%d of %d)\n",
1075				(int)(svsk->sk_tcplen - sizeof(rpc_fraghdr)),
1076				svc_sock_reclen(svsk));
1077		goto err_noclose;
1078	}
1079
1080	if (svsk->sk_datalen < 8) {
1081		svsk->sk_datalen = 0;
1082		goto err_delete; /* client is nuts. */
1083	}
1084
1085	rqstp->rq_arg.len = svsk->sk_datalen;
1086	rqstp->rq_arg.page_base = 0;
1087	if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len) {
1088		rqstp->rq_arg.head[0].iov_len = rqstp->rq_arg.len;
1089		rqstp->rq_arg.page_len = 0;
1090	} else
1091		rqstp->rq_arg.page_len = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len;
1092
1093	rqstp->rq_xprt_ctxt   = NULL;
1094	rqstp->rq_prot	      = IPPROTO_TCP;
1095	if (test_bit(XPT_LOCAL, &svsk->sk_xprt.xpt_flags))
1096		set_bit(RQ_LOCAL, &rqstp->rq_flags);
1097	else
1098		clear_bit(RQ_LOCAL, &rqstp->rq_flags);
1099
1100	p = (__be32 *)rqstp->rq_arg.head[0].iov_base;
1101	calldir = p[1];
1102	if (calldir)
1103		len = receive_cb_reply(svsk, rqstp);
1104
1105	/* Reset TCP read info */
1106	svsk->sk_datalen = 0;
1107	svc_tcp_fragment_received(svsk);
1108
1109	if (len < 0)
1110		goto error;
1111
1112	svc_xprt_copy_addrs(rqstp, &svsk->sk_xprt);
1113	if (serv->sv_stats)
1114		serv->sv_stats->nettcpcnt++;
1115
1116	return rqstp->rq_arg.len;
1117
1118error:
1119	if (len != -EAGAIN)
1120		goto err_delete;
1121	dprintk("RPC: TCP recvfrom got EAGAIN\n");
1122	return 0;
1123err_delete:
1124	printk(KERN_NOTICE "%s: recvfrom returned errno %d\n",
1125	       svsk->sk_xprt.xpt_server->sv_name, -len);
1126	set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1127err_noclose:
1128	return 0;	/* record not complete */
1129}
1130
1131/*
1132 * Send out data on TCP socket.
1133 */
1134static int svc_tcp_sendto(struct svc_rqst *rqstp)
1135{
1136	struct xdr_buf	*xbufp = &rqstp->rq_res;
1137	int sent;
1138	__be32 reclen;
1139
1140	/* Set up the first element of the reply kvec.
1141	 * Any other kvecs that may be in use have been taken
1142	 * care of by the server implementation itself.
1143	 */
1144	reclen = htonl(0x80000000|((xbufp->len ) - 4));
1145	memcpy(xbufp->head[0].iov_base, &reclen, 4);
1146
1147	sent = svc_sendto(rqstp, &rqstp->rq_res);
1148	if (sent != xbufp->len) {
1149		printk(KERN_NOTICE
1150		       "rpc-srv/tcp: %s: %s %d when sending %d bytes "
1151		       "- shutting down socket\n",
1152		       rqstp->rq_xprt->xpt_server->sv_name,
1153		       (sent<0)?"got error":"sent only",
1154		       sent, xbufp->len);
1155		set_bit(XPT_CLOSE, &rqstp->rq_xprt->xpt_flags);
1156		svc_xprt_enqueue(rqstp->rq_xprt);
1157		sent = -EAGAIN;
1158	}
1159	return sent;
1160}
1161
 
 
 
 
 
 
 
 
 
 
 
1162static struct svc_xprt *svc_tcp_create(struct svc_serv *serv,
1163				       struct net *net,
1164				       struct sockaddr *sa, int salen,
1165				       int flags)
1166{
1167	return svc_create_socket(serv, IPPROTO_TCP, net, sa, salen, flags);
1168}
1169
1170static const struct svc_xprt_ops svc_tcp_ops = {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1171	.xpo_create = svc_tcp_create,
1172	.xpo_recvfrom = svc_tcp_recvfrom,
1173	.xpo_sendto = svc_tcp_sendto,
1174	.xpo_release_rqst = svc_release_skb,
1175	.xpo_detach = svc_tcp_sock_detach,
1176	.xpo_free = svc_sock_free,
 
1177	.xpo_has_wspace = svc_tcp_has_wspace,
1178	.xpo_accept = svc_tcp_accept,
1179	.xpo_secure_port = svc_sock_secure_port,
1180	.xpo_kill_temp_xprt = svc_tcp_kill_temp_xprt,
1181};
1182
1183static struct svc_xprt_class svc_tcp_class = {
1184	.xcl_name = "tcp",
1185	.xcl_owner = THIS_MODULE,
1186	.xcl_ops = &svc_tcp_ops,
1187	.xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP,
1188	.xcl_ident = XPRT_TRANSPORT_TCP,
1189};
1190
1191void svc_init_xprt_sock(void)
1192{
1193	svc_reg_xprt_class(&svc_tcp_class);
1194	svc_reg_xprt_class(&svc_udp_class);
 
1195}
1196
1197void svc_cleanup_xprt_sock(void)
1198{
1199	svc_unreg_xprt_class(&svc_tcp_class);
1200	svc_unreg_xprt_class(&svc_udp_class);
 
1201}
1202
1203static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv)
1204{
1205	struct sock	*sk = svsk->sk_sk;
1206
1207	svc_xprt_init(sock_net(svsk->sk_sock->sk), &svc_tcp_class,
1208		      &svsk->sk_xprt, serv);
1209	set_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
1210	set_bit(XPT_CONG_CTRL, &svsk->sk_xprt.xpt_flags);
1211	if (sk->sk_state == TCP_LISTEN) {
1212		dprintk("setting up TCP socket for listening\n");
1213		strcpy(svsk->sk_xprt.xpt_remotebuf, "listener");
1214		set_bit(XPT_LISTENER, &svsk->sk_xprt.xpt_flags);
1215		sk->sk_data_ready = svc_tcp_listen_data_ready;
1216		set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
1217	} else {
1218		dprintk("setting up TCP socket for reading\n");
1219		sk->sk_state_change = svc_tcp_state_change;
1220		sk->sk_data_ready = svc_data_ready;
1221		sk->sk_write_space = svc_write_space;
1222
1223		svsk->sk_reclen = 0;
1224		svsk->sk_tcplen = 0;
1225		svsk->sk_datalen = 0;
1226		memset(&svsk->sk_pages[0], 0, sizeof(svsk->sk_pages));
1227
1228		tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
1229
1230		set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
1231		switch (sk->sk_state) {
1232		case TCP_SYN_RECV:
1233		case TCP_ESTABLISHED:
1234			break;
1235		default:
1236			set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1237		}
1238	}
1239}
1240
1241void svc_sock_update_bufs(struct svc_serv *serv)
1242{
1243	/*
1244	 * The number of server threads has changed. Update
1245	 * rcvbuf and sndbuf accordingly on all sockets
1246	 */
1247	struct svc_sock *svsk;
1248
1249	spin_lock_bh(&serv->sv_lock);
1250	list_for_each_entry(svsk, &serv->sv_permsocks, sk_xprt.xpt_list)
1251		set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
1252	spin_unlock_bh(&serv->sv_lock);
1253}
1254EXPORT_SYMBOL_GPL(svc_sock_update_bufs);
1255
1256/*
1257 * Initialize socket for RPC use and create svc_sock struct
1258 */
1259static struct svc_sock *svc_setup_socket(struct svc_serv *serv,
1260						struct socket *sock,
1261						int flags)
1262{
1263	struct svc_sock	*svsk;
1264	struct sock	*inet;
1265	int		pmap_register = !(flags & SVC_SOCK_ANONYMOUS);
1266	int		err = 0;
1267
1268	dprintk("svc: svc_setup_socket %p\n", sock);
1269	svsk = kzalloc(sizeof(*svsk), GFP_KERNEL);
1270	if (!svsk)
1271		return ERR_PTR(-ENOMEM);
1272
1273	inet = sock->sk;
1274
1275	/* Register socket with portmapper */
1276	if (pmap_register)
1277		err = svc_register(serv, sock_net(sock->sk), inet->sk_family,
1278				     inet->sk_protocol,
1279				     ntohs(inet_sk(inet)->inet_sport));
1280
1281	if (err < 0) {
1282		kfree(svsk);
1283		return ERR_PTR(err);
1284	}
1285
 
1286	svsk->sk_sock = sock;
1287	svsk->sk_sk = inet;
1288	svsk->sk_ostate = inet->sk_state_change;
1289	svsk->sk_odata = inet->sk_data_ready;
1290	svsk->sk_owspace = inet->sk_write_space;
1291	/*
1292	 * This barrier is necessary in order to prevent race condition
1293	 * with svc_data_ready(), svc_listen_data_ready() and others
1294	 * when calling callbacks above.
1295	 */
1296	wmb();
1297	inet->sk_user_data = svsk;
1298
1299	/* Initialize the socket */
1300	if (sock->type == SOCK_DGRAM)
1301		svc_udp_init(svsk, serv);
1302	else
 
 
 
 
 
1303		svc_tcp_init(svsk, serv);
 
1304
1305	dprintk("svc: svc_setup_socket created %p (inet %p), "
1306			"listen %d close %d\n",
1307			svsk, svsk->sk_sk,
1308			test_bit(XPT_LISTENER, &svsk->sk_xprt.xpt_flags),
1309			test_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags));
1310
1311	return svsk;
1312}
1313
1314bool svc_alien_sock(struct net *net, int fd)
1315{
1316	int err;
1317	struct socket *sock = sockfd_lookup(fd, &err);
1318	bool ret = false;
1319
1320	if (!sock)
1321		goto out;
1322	if (sock_net(sock->sk) != net)
1323		ret = true;
1324	sockfd_put(sock);
1325out:
1326	return ret;
1327}
1328EXPORT_SYMBOL_GPL(svc_alien_sock);
1329
1330/**
1331 * svc_addsock - add a listener socket to an RPC service
1332 * @serv: pointer to RPC service to which to add a new listener
1333 * @fd: file descriptor of the new listener
1334 * @name_return: pointer to buffer to fill in with name of listener
1335 * @len: size of the buffer
1336 * @cred: credential
1337 *
1338 * Fills in socket name and returns positive length of name if successful.
1339 * Name is terminated with '\n'.  On error, returns a negative errno
1340 * value.
1341 */
1342int svc_addsock(struct svc_serv *serv, const int fd, char *name_return,
1343		const size_t len, const struct cred *cred)
1344{
1345	int err = 0;
1346	struct socket *so = sockfd_lookup(fd, &err);
1347	struct svc_sock *svsk = NULL;
1348	struct sockaddr_storage addr;
1349	struct sockaddr *sin = (struct sockaddr *)&addr;
1350	int salen;
1351
1352	if (!so)
1353		return err;
1354	err = -EAFNOSUPPORT;
1355	if ((so->sk->sk_family != PF_INET) && (so->sk->sk_family != PF_INET6))
1356		goto out;
1357	err =  -EPROTONOSUPPORT;
1358	if (so->sk->sk_protocol != IPPROTO_TCP &&
1359	    so->sk->sk_protocol != IPPROTO_UDP)
1360		goto out;
1361	err = -EISCONN;
1362	if (so->state > SS_UNCONNECTED)
1363		goto out;
1364	err = -ENOENT;
1365	if (!try_module_get(THIS_MODULE))
1366		goto out;
1367	svsk = svc_setup_socket(serv, so, SVC_SOCK_DEFAULTS);
1368	if (IS_ERR(svsk)) {
1369		module_put(THIS_MODULE);
1370		err = PTR_ERR(svsk);
1371		goto out;
1372	}
1373	salen = kernel_getsockname(svsk->sk_sock, sin);
1374	if (salen >= 0)
1375		svc_xprt_set_local(&svsk->sk_xprt, sin, salen);
1376	svsk->sk_xprt.xpt_cred = get_cred(cred);
1377	svc_add_new_perm_xprt(serv, &svsk->sk_xprt);
1378	return svc_one_sock_name(svsk, name_return, len);
1379out:
1380	sockfd_put(so);
1381	return err;
1382}
1383EXPORT_SYMBOL_GPL(svc_addsock);
1384
1385/*
1386 * Create socket for RPC service.
1387 */
1388static struct svc_xprt *svc_create_socket(struct svc_serv *serv,
1389					  int protocol,
1390					  struct net *net,
1391					  struct sockaddr *sin, int len,
1392					  int flags)
1393{
1394	struct svc_sock	*svsk;
1395	struct socket	*sock;
1396	int		error;
1397	int		type;
1398	struct sockaddr_storage addr;
1399	struct sockaddr *newsin = (struct sockaddr *)&addr;
1400	int		newlen;
1401	int		family;
1402	int		val;
1403	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
1404
1405	dprintk("svc: svc_create_socket(%s, %d, %s)\n",
1406			serv->sv_program->pg_name, protocol,
1407			__svc_print_addr(sin, buf, sizeof(buf)));
1408
1409	if (protocol != IPPROTO_UDP && protocol != IPPROTO_TCP) {
1410		printk(KERN_WARNING "svc: only UDP and TCP "
1411				"sockets supported\n");
1412		return ERR_PTR(-EINVAL);
1413	}
1414
1415	type = (protocol == IPPROTO_UDP)? SOCK_DGRAM : SOCK_STREAM;
1416	switch (sin->sa_family) {
1417	case AF_INET6:
1418		family = PF_INET6;
1419		break;
1420	case AF_INET:
1421		family = PF_INET;
1422		break;
1423	default:
1424		return ERR_PTR(-EINVAL);
1425	}
1426
1427	error = __sock_create(net, family, type, protocol, &sock, 1);
1428	if (error < 0)
1429		return ERR_PTR(error);
1430
1431	svc_reclassify_socket(sock);
1432
1433	/*
1434	 * If this is an PF_INET6 listener, we want to avoid
1435	 * getting requests from IPv4 remotes.  Those should
1436	 * be shunted to a PF_INET listener via rpcbind.
1437	 */
1438	val = 1;
1439	if (family == PF_INET6)
1440		kernel_setsockopt(sock, SOL_IPV6, IPV6_V6ONLY,
1441					(char *)&val, sizeof(val));
1442
1443	if (type == SOCK_STREAM)
1444		sock->sk->sk_reuse = SK_CAN_REUSE; /* allow address reuse */
1445	error = kernel_bind(sock, sin, len);
1446	if (error < 0)
1447		goto bummer;
1448
1449	error = kernel_getsockname(sock, newsin);
 
1450	if (error < 0)
1451		goto bummer;
1452	newlen = error;
1453
1454	if (protocol == IPPROTO_TCP) {
1455		if ((error = kernel_listen(sock, 64)) < 0)
1456			goto bummer;
1457	}
1458
1459	svsk = svc_setup_socket(serv, sock, flags);
1460	if (IS_ERR(svsk)) {
1461		error = PTR_ERR(svsk);
1462		goto bummer;
1463	}
1464	svc_xprt_set_local(&svsk->sk_xprt, newsin, newlen);
1465	return (struct svc_xprt *)svsk;
1466bummer:
1467	dprintk("svc: svc_create_socket error = %d\n", -error);
1468	sock_release(sock);
1469	return ERR_PTR(error);
1470}
1471
1472/*
1473 * Detach the svc_sock from the socket so that no
1474 * more callbacks occur.
1475 */
1476static void svc_sock_detach(struct svc_xprt *xprt)
1477{
1478	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1479	struct sock *sk = svsk->sk_sk;
 
1480
1481	dprintk("svc: svc_sock_detach(%p)\n", svsk);
1482
1483	/* put back the old socket callbacks */
1484	lock_sock(sk);
1485	sk->sk_state_change = svsk->sk_ostate;
1486	sk->sk_data_ready = svsk->sk_odata;
1487	sk->sk_write_space = svsk->sk_owspace;
1488	sk->sk_user_data = NULL;
1489	release_sock(sk);
 
 
1490}
1491
1492/*
1493 * Disconnect the socket, and reset the callbacks
1494 */
1495static void svc_tcp_sock_detach(struct svc_xprt *xprt)
1496{
1497	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1498
1499	dprintk("svc: svc_tcp_sock_detach(%p)\n", svsk);
1500
1501	svc_sock_detach(xprt);
1502
1503	if (!test_bit(XPT_LISTENER, &xprt->xpt_flags)) {
1504		svc_tcp_clear_pages(svsk);
1505		kernel_sock_shutdown(svsk->sk_sock, SHUT_RDWR);
1506	}
1507}
1508
1509/*
1510 * Free the svc_sock's socket resources and the svc_sock itself.
1511 */
1512static void svc_sock_free(struct svc_xprt *xprt)
1513{
1514	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1515	dprintk("svc: svc_sock_free(%p)\n", svsk);
1516
1517	if (svsk->sk_sock->file)
1518		sockfd_put(svsk->sk_sock);
1519	else
1520		sock_release(svsk->sk_sock);
1521	kfree(svsk);
1522}
v4.6
 
   1/*
   2 * linux/net/sunrpc/svcsock.c
   3 *
   4 * These are the RPC server socket internals.
   5 *
   6 * The server scheduling algorithm does not always distribute the load
   7 * evenly when servicing a single client. May need to modify the
   8 * svc_xprt_enqueue procedure...
   9 *
  10 * TCP support is largely untested and may be a little slow. The problem
  11 * is that we currently do two separate recvfrom's, one for the 4-byte
  12 * record length, and the second for the actual record. This could possibly
  13 * be improved by always reading a minimum size of around 100 bytes and
  14 * tucking any superfluous bytes away in a temporary store. Still, that
  15 * leaves write requests out in the rain. An alternative may be to peek at
  16 * the first skb in the queue, and if it matches the next TCP sequence
  17 * number, to extract the record marker. Yuck.
  18 *
  19 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
  20 */
  21
  22#include <linux/kernel.h>
  23#include <linux/sched.h>
  24#include <linux/module.h>
  25#include <linux/errno.h>
  26#include <linux/fcntl.h>
  27#include <linux/net.h>
  28#include <linux/in.h>
  29#include <linux/inet.h>
  30#include <linux/udp.h>
  31#include <linux/tcp.h>
  32#include <linux/unistd.h>
  33#include <linux/slab.h>
  34#include <linux/netdevice.h>
  35#include <linux/skbuff.h>
  36#include <linux/file.h>
  37#include <linux/freezer.h>
  38#include <net/sock.h>
  39#include <net/checksum.h>
  40#include <net/ip.h>
  41#include <net/ipv6.h>
 
  42#include <net/tcp.h>
  43#include <net/tcp_states.h>
  44#include <asm/uaccess.h>
  45#include <asm/ioctls.h>
  46#include <trace/events/skb.h>
  47
  48#include <linux/sunrpc/types.h>
  49#include <linux/sunrpc/clnt.h>
  50#include <linux/sunrpc/xdr.h>
  51#include <linux/sunrpc/msg_prot.h>
  52#include <linux/sunrpc/svcsock.h>
  53#include <linux/sunrpc/stats.h>
  54#include <linux/sunrpc/xprt.h>
  55
  56#include "sunrpc.h"
  57
  58#define RPCDBG_FACILITY	RPCDBG_SVCXPRT
  59
  60
  61static struct svc_sock *svc_setup_socket(struct svc_serv *, struct socket *,
  62					 int flags);
  63static void		svc_udp_data_ready(struct sock *);
  64static int		svc_udp_recvfrom(struct svc_rqst *);
  65static int		svc_udp_sendto(struct svc_rqst *);
  66static void		svc_sock_detach(struct svc_xprt *);
  67static void		svc_tcp_sock_detach(struct svc_xprt *);
  68static void		svc_sock_free(struct svc_xprt *);
  69
  70static struct svc_xprt *svc_create_socket(struct svc_serv *, int,
  71					  struct net *, struct sockaddr *,
  72					  int, int);
  73#if defined(CONFIG_SUNRPC_BACKCHANNEL)
  74static struct svc_xprt *svc_bc_create_socket(struct svc_serv *, int,
  75					     struct net *, struct sockaddr *,
  76					     int, int);
  77static void svc_bc_sock_free(struct svc_xprt *xprt);
  78#endif /* CONFIG_SUNRPC_BACKCHANNEL */
  79
  80#ifdef CONFIG_DEBUG_LOCK_ALLOC
  81static struct lock_class_key svc_key[2];
  82static struct lock_class_key svc_slock_key[2];
  83
  84static void svc_reclassify_socket(struct socket *sock)
  85{
  86	struct sock *sk = sock->sk;
  87
  88	WARN_ON_ONCE(sock_owned_by_user(sk));
  89	if (sock_owned_by_user(sk))
  90		return;
  91
  92	switch (sk->sk_family) {
  93	case AF_INET:
  94		sock_lock_init_class_and_name(sk, "slock-AF_INET-NFSD",
  95					      &svc_slock_key[0],
  96					      "sk_xprt.xpt_lock-AF_INET-NFSD",
  97					      &svc_key[0]);
  98		break;
  99
 100	case AF_INET6:
 101		sock_lock_init_class_and_name(sk, "slock-AF_INET6-NFSD",
 102					      &svc_slock_key[1],
 103					      "sk_xprt.xpt_lock-AF_INET6-NFSD",
 104					      &svc_key[1]);
 105		break;
 106
 107	default:
 108		BUG();
 109	}
 110}
 111#else
 112static void svc_reclassify_socket(struct socket *sock)
 113{
 114}
 115#endif
 116
 117/*
 118 * Release an skbuff after use
 119 */
 120static void svc_release_skb(struct svc_rqst *rqstp)
 121{
 122	struct sk_buff *skb = rqstp->rq_xprt_ctxt;
 123
 124	if (skb) {
 125		struct svc_sock *svsk =
 126			container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 127		rqstp->rq_xprt_ctxt = NULL;
 128
 129		dprintk("svc: service %p, releasing skb %p\n", rqstp, skb);
 130		skb_free_datagram_locked(svsk->sk_sk, skb);
 131	}
 132}
 133
 
 
 
 
 
 
 
 
 
 
 
 
 134union svc_pktinfo_u {
 135	struct in_pktinfo pkti;
 136	struct in6_pktinfo pkti6;
 137};
 138#define SVC_PKTINFO_SPACE \
 139	CMSG_SPACE(sizeof(union svc_pktinfo_u))
 140
 141static void svc_set_cmsg_data(struct svc_rqst *rqstp, struct cmsghdr *cmh)
 142{
 143	struct svc_sock *svsk =
 144		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 145	switch (svsk->sk_sk->sk_family) {
 146	case AF_INET: {
 147			struct in_pktinfo *pki = CMSG_DATA(cmh);
 148
 149			cmh->cmsg_level = SOL_IP;
 150			cmh->cmsg_type = IP_PKTINFO;
 151			pki->ipi_ifindex = 0;
 152			pki->ipi_spec_dst.s_addr =
 153				 svc_daddr_in(rqstp)->sin_addr.s_addr;
 154			cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
 155		}
 156		break;
 157
 158	case AF_INET6: {
 159			struct in6_pktinfo *pki = CMSG_DATA(cmh);
 160			struct sockaddr_in6 *daddr = svc_daddr_in6(rqstp);
 161
 162			cmh->cmsg_level = SOL_IPV6;
 163			cmh->cmsg_type = IPV6_PKTINFO;
 164			pki->ipi6_ifindex = daddr->sin6_scope_id;
 165			pki->ipi6_addr = daddr->sin6_addr;
 166			cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
 167		}
 168		break;
 169	}
 170}
 171
 172/*
 173 * send routine intended to be shared by the fore- and back-channel
 174 */
 175int svc_send_common(struct socket *sock, struct xdr_buf *xdr,
 176		    struct page *headpage, unsigned long headoffset,
 177		    struct page *tailpage, unsigned long tailoffset)
 178{
 179	int		result;
 180	int		size;
 181	struct page	**ppage = xdr->pages;
 182	size_t		base = xdr->page_base;
 183	unsigned int	pglen = xdr->page_len;
 184	unsigned int	flags = MSG_MORE | MSG_SENDPAGE_NOTLAST;
 185	int		slen;
 186	int		len = 0;
 187
 188	slen = xdr->len;
 189
 190	/* send head */
 191	if (slen == xdr->head[0].iov_len)
 192		flags = 0;
 193	len = kernel_sendpage(sock, headpage, headoffset,
 194				  xdr->head[0].iov_len, flags);
 195	if (len != xdr->head[0].iov_len)
 196		goto out;
 197	slen -= xdr->head[0].iov_len;
 198	if (slen == 0)
 199		goto out;
 200
 201	/* send page data */
 202	size = PAGE_SIZE - base < pglen ? PAGE_SIZE - base : pglen;
 203	while (pglen > 0) {
 204		if (slen == size)
 205			flags = 0;
 206		result = kernel_sendpage(sock, *ppage, base, size, flags);
 207		if (result > 0)
 208			len += result;
 209		if (result != size)
 210			goto out;
 211		slen -= size;
 212		pglen -= size;
 213		size = PAGE_SIZE < pglen ? PAGE_SIZE : pglen;
 214		base = 0;
 215		ppage++;
 216	}
 217
 218	/* send tail */
 219	if (xdr->tail[0].iov_len) {
 220		result = kernel_sendpage(sock, tailpage, tailoffset,
 221				   xdr->tail[0].iov_len, 0);
 222		if (result > 0)
 223			len += result;
 224	}
 225
 226out:
 227	return len;
 228}
 229
 230
 231/*
 232 * Generic sendto routine
 233 */
 234static int svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr)
 235{
 236	struct svc_sock	*svsk =
 237		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 238	struct socket	*sock = svsk->sk_sock;
 239	union {
 240		struct cmsghdr	hdr;
 241		long		all[SVC_PKTINFO_SPACE / sizeof(long)];
 242	} buffer;
 243	struct cmsghdr *cmh = &buffer.hdr;
 244	int		len = 0;
 245	unsigned long tailoff;
 246	unsigned long headoff;
 247	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
 248
 249	if (rqstp->rq_prot == IPPROTO_UDP) {
 250		struct msghdr msg = {
 251			.msg_name	= &rqstp->rq_addr,
 252			.msg_namelen	= rqstp->rq_addrlen,
 253			.msg_control	= cmh,
 254			.msg_controllen	= sizeof(buffer),
 255			.msg_flags	= MSG_MORE,
 256		};
 257
 258		svc_set_cmsg_data(rqstp, cmh);
 259
 260		if (sock_sendmsg(sock, &msg) < 0)
 261			goto out;
 262	}
 263
 264	tailoff = ((unsigned long)xdr->tail[0].iov_base) & (PAGE_SIZE-1);
 265	headoff = 0;
 266	len = svc_send_common(sock, xdr, rqstp->rq_respages[0], headoff,
 267			       rqstp->rq_respages[0], tailoff);
 268
 269out:
 270	dprintk("svc: socket %p sendto([%p %Zu... ], %d) = %d (addr %s)\n",
 271		svsk, xdr->head[0].iov_base, xdr->head[0].iov_len,
 272		xdr->len, len, svc_print_addr(rqstp, buf, sizeof(buf)));
 273
 274	return len;
 275}
 276
 277/*
 278 * Report socket names for nfsdfs
 279 */
 280static int svc_one_sock_name(struct svc_sock *svsk, char *buf, int remaining)
 281{
 282	const struct sock *sk = svsk->sk_sk;
 283	const char *proto_name = sk->sk_protocol == IPPROTO_UDP ?
 284							"udp" : "tcp";
 285	int len;
 286
 287	switch (sk->sk_family) {
 288	case PF_INET:
 289		len = snprintf(buf, remaining, "ipv4 %s %pI4 %d\n",
 290				proto_name,
 291				&inet_sk(sk)->inet_rcv_saddr,
 292				inet_sk(sk)->inet_num);
 293		break;
 294#if IS_ENABLED(CONFIG_IPV6)
 295	case PF_INET6:
 296		len = snprintf(buf, remaining, "ipv6 %s %pI6 %d\n",
 297				proto_name,
 298				&sk->sk_v6_rcv_saddr,
 299				inet_sk(sk)->inet_num);
 300		break;
 301#endif
 302	default:
 303		len = snprintf(buf, remaining, "*unknown-%d*\n",
 304				sk->sk_family);
 305	}
 306
 307	if (len >= remaining) {
 308		*buf = '\0';
 309		return -ENAMETOOLONG;
 310	}
 311	return len;
 312}
 313
 314/*
 315 * Generic recvfrom routine.
 316 */
 317static int svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr,
 318			int buflen)
 319{
 320	struct svc_sock *svsk =
 321		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 322	struct msghdr msg = {
 323		.msg_flags	= MSG_DONTWAIT,
 324	};
 325	int len;
 326
 327	rqstp->rq_xprt_hlen = 0;
 328
 329	clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 330	len = kernel_recvmsg(svsk->sk_sock, &msg, iov, nr, buflen,
 331				msg.msg_flags);
 
 
 
 
 332	/* If we read a full record, then assume there may be more
 333	 * data to read (stream based sockets only!)
 334	 */
 335	if (len == buflen)
 336		set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 337
 338	dprintk("svc: socket %p recvfrom(%p, %Zu) = %d\n",
 339		svsk, iov[0].iov_base, iov[0].iov_len, len);
 340	return len;
 341}
 342
 343static int svc_partial_recvfrom(struct svc_rqst *rqstp,
 344				struct kvec *iov, int nr,
 345				int buflen, unsigned int base)
 346{
 347	size_t save_iovlen;
 348	void *save_iovbase;
 349	unsigned int i;
 350	int ret;
 351
 352	if (base == 0)
 353		return svc_recvfrom(rqstp, iov, nr, buflen);
 354
 355	for (i = 0; i < nr; i++) {
 356		if (iov[i].iov_len > base)
 357			break;
 358		base -= iov[i].iov_len;
 359	}
 360	save_iovlen = iov[i].iov_len;
 361	save_iovbase = iov[i].iov_base;
 362	iov[i].iov_len -= base;
 363	iov[i].iov_base += base;
 364	ret = svc_recvfrom(rqstp, &iov[i], nr - i, buflen);
 365	iov[i].iov_len = save_iovlen;
 366	iov[i].iov_base = save_iovbase;
 367	return ret;
 368}
 369
 370/*
 371 * Set socket snd and rcv buffer lengths
 372 */
 373static void svc_sock_setbufsize(struct socket *sock, unsigned int snd,
 374				unsigned int rcv)
 375{
 376#if 0
 377	mm_segment_t	oldfs;
 378	oldfs = get_fs(); set_fs(KERNEL_DS);
 379	sock_setsockopt(sock, SOL_SOCKET, SO_SNDBUF,
 380			(char*)&snd, sizeof(snd));
 381	sock_setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 382			(char*)&rcv, sizeof(rcv));
 383#else
 384	/* sock_setsockopt limits use to sysctl_?mem_max,
 385	 * which isn't acceptable.  Until that is made conditional
 386	 * on not having CAP_SYS_RESOURCE or similar, we go direct...
 387	 * DaveM said I could!
 388	 */
 389	lock_sock(sock->sk);
 390	sock->sk->sk_sndbuf = snd * 2;
 391	sock->sk->sk_rcvbuf = rcv * 2;
 392	sock->sk->sk_write_space(sock->sk);
 393	release_sock(sock->sk);
 394#endif
 395}
 396
 397static int svc_sock_secure_port(struct svc_rqst *rqstp)
 398{
 399	return svc_port_is_privileged(svc_addr(rqstp));
 400}
 401
 402static bool sunrpc_waitqueue_active(wait_queue_head_t *wq)
 403{
 404	if (!wq)
 405		return false;
 406	/*
 407	 * There should normally be a memory * barrier here--see
 408	 * wq_has_sleeper().
 409	 *
 410	 * It appears that isn't currently necessary, though, basically
 411	 * because callers all appear to have sufficient memory barriers
 412	 * between the time the relevant change is made and the
 413	 * time they call these callbacks.
 414	 *
 415	 * The nfsd code itself doesn't actually explicitly wait on
 416	 * these waitqueues, but it may wait on them for example in
 417	 * sendpage() or sendmsg() calls.  (And those may be the only
 418	 * places, since it it uses nonblocking reads.)
 419	 *
 420	 * Maybe we should add the memory barriers anyway, but these are
 421	 * hot paths so we'd need to be convinced there's no sigificant
 422	 * penalty.
 423	 */
 424	return waitqueue_active(wq);
 425}
 426
 427/*
 428 * INET callback when data has been received on the socket.
 429 */
 430static void svc_udp_data_ready(struct sock *sk)
 431{
 432	struct svc_sock	*svsk = (struct svc_sock *)sk->sk_user_data;
 433	wait_queue_head_t *wq = sk_sleep(sk);
 434
 435	if (svsk) {
 436		dprintk("svc: socket %p(inet %p), busy=%d\n",
 437			svsk, sk,
 438			test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags));
 439		set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 440		svc_xprt_enqueue(&svsk->sk_xprt);
 
 
 
 
 441	}
 442	if (sunrpc_waitqueue_active(wq))
 443		wake_up_interruptible(wq);
 444}
 445
 446/*
 447 * INET callback when space is newly available on the socket.
 448 */
 449static void svc_write_space(struct sock *sk)
 450{
 451	struct svc_sock	*svsk = (struct svc_sock *)(sk->sk_user_data);
 452	wait_queue_head_t *wq = sk_sleep(sk);
 453
 454	if (svsk) {
 455		dprintk("svc: socket %p(inet %p), write_space busy=%d\n",
 456			svsk, sk, test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags));
 
 
 
 
 457		svc_xprt_enqueue(&svsk->sk_xprt);
 458	}
 459
 460	if (sunrpc_waitqueue_active(wq)) {
 461		dprintk("RPC svc_write_space: someone sleeping on %p\n",
 462		       svsk);
 463		wake_up_interruptible(wq);
 464	}
 465}
 466
 467static int svc_tcp_has_wspace(struct svc_xprt *xprt)
 468{
 469	struct svc_sock *svsk =	container_of(xprt, struct svc_sock, sk_xprt);
 470	struct svc_serv *serv = svsk->sk_xprt.xpt_server;
 471	int required;
 472
 473	if (test_bit(XPT_LISTENER, &xprt->xpt_flags))
 474		return 1;
 475	required = atomic_read(&xprt->xpt_reserved) + serv->sv_max_mesg;
 476	if (sk_stream_wspace(svsk->sk_sk) >= required ||
 477	    (sk_stream_min_wspace(svsk->sk_sk) == 0 &&
 478	     atomic_read(&xprt->xpt_reserved) == 0))
 479		return 1;
 480	set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
 481	return 0;
 482}
 483
 484static void svc_tcp_write_space(struct sock *sk)
 485{
 486	struct svc_sock *svsk = (struct svc_sock *)(sk->sk_user_data);
 487	struct socket *sock = sk->sk_socket;
 
 
 
 
 488
 489	if (!sk_stream_is_writeable(sk) || !sock)
 490		return;
 491	if (!svsk || svc_tcp_has_wspace(&svsk->sk_xprt))
 492		clear_bit(SOCK_NOSPACE, &sock->flags);
 493	svc_write_space(sk);
 494}
 495
 496static void svc_tcp_adjust_wspace(struct svc_xprt *xprt)
 497{
 498	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
 499
 500	if (svc_tcp_has_wspace(xprt))
 501		clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
 502}
 503
 504/*
 505 * See net/ipv6/ip_sockglue.c : ip_cmsg_recv_pktinfo
 506 */
 507static int svc_udp_get_dest_address4(struct svc_rqst *rqstp,
 508				     struct cmsghdr *cmh)
 509{
 510	struct in_pktinfo *pki = CMSG_DATA(cmh);
 511	struct sockaddr_in *daddr = svc_daddr_in(rqstp);
 512
 513	if (cmh->cmsg_type != IP_PKTINFO)
 514		return 0;
 515
 516	daddr->sin_family = AF_INET;
 517	daddr->sin_addr.s_addr = pki->ipi_spec_dst.s_addr;
 518	return 1;
 519}
 520
 521/*
 522 * See net/ipv6/datagram.c : ip6_datagram_recv_ctl
 523 */
 524static int svc_udp_get_dest_address6(struct svc_rqst *rqstp,
 525				     struct cmsghdr *cmh)
 526{
 527	struct in6_pktinfo *pki = CMSG_DATA(cmh);
 528	struct sockaddr_in6 *daddr = svc_daddr_in6(rqstp);
 529
 530	if (cmh->cmsg_type != IPV6_PKTINFO)
 531		return 0;
 532
 533	daddr->sin6_family = AF_INET6;
 534	daddr->sin6_addr = pki->ipi6_addr;
 535	daddr->sin6_scope_id = pki->ipi6_ifindex;
 536	return 1;
 537}
 538
 539/*
 540 * Copy the UDP datagram's destination address to the rqstp structure.
 541 * The 'destination' address in this case is the address to which the
 542 * peer sent the datagram, i.e. our local address. For multihomed
 543 * hosts, this can change from msg to msg. Note that only the IP
 544 * address changes, the port number should remain the same.
 545 */
 546static int svc_udp_get_dest_address(struct svc_rqst *rqstp,
 547				    struct cmsghdr *cmh)
 548{
 549	switch (cmh->cmsg_level) {
 550	case SOL_IP:
 551		return svc_udp_get_dest_address4(rqstp, cmh);
 552	case SOL_IPV6:
 553		return svc_udp_get_dest_address6(rqstp, cmh);
 554	}
 555
 556	return 0;
 557}
 558
 559/*
 560 * Receive a datagram from a UDP socket.
 561 */
 562static int svc_udp_recvfrom(struct svc_rqst *rqstp)
 563{
 564	struct svc_sock	*svsk =
 565		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 566	struct svc_serv	*serv = svsk->sk_xprt.xpt_server;
 567	struct sk_buff	*skb;
 568	union {
 569		struct cmsghdr	hdr;
 570		long		all[SVC_PKTINFO_SPACE / sizeof(long)];
 571	} buffer;
 572	struct cmsghdr *cmh = &buffer.hdr;
 573	struct msghdr msg = {
 574		.msg_name = svc_addr(rqstp),
 575		.msg_control = cmh,
 576		.msg_controllen = sizeof(buffer),
 577		.msg_flags = MSG_DONTWAIT,
 578	};
 579	size_t len;
 580	int err;
 581
 582	if (test_and_clear_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags))
 583	    /* udp sockets need large rcvbuf as all pending
 584	     * requests are still in that buffer.  sndbuf must
 585	     * also be large enough that there is enough space
 586	     * for one reply per thread.  We count all threads
 587	     * rather than threads in a particular pool, which
 588	     * provides an upper bound on the number of threads
 589	     * which will access the socket.
 590	     */
 591	    svc_sock_setbufsize(svsk->sk_sock,
 592				(serv->sv_nrthreads+3) * serv->sv_max_mesg,
 593				(serv->sv_nrthreads+3) * serv->sv_max_mesg);
 594
 595	clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 596	skb = NULL;
 597	err = kernel_recvmsg(svsk->sk_sock, &msg, NULL,
 598			     0, 0, MSG_PEEK | MSG_DONTWAIT);
 599	if (err >= 0)
 600		skb = skb_recv_datagram(svsk->sk_sk, 0, 1, &err);
 601
 602	if (skb == NULL) {
 603		if (err != -EAGAIN) {
 604			/* possibly an icmp error */
 605			dprintk("svc: recvfrom returned error %d\n", -err);
 606			set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 607		}
 608		return 0;
 609	}
 610	len = svc_addr_len(svc_addr(rqstp));
 611	rqstp->rq_addrlen = len;
 612	if (skb->tstamp.tv64 == 0) {
 613		skb->tstamp = ktime_get_real();
 614		/* Don't enable netstamp, sunrpc doesn't
 615		   need that much accuracy */
 616	}
 617	svsk->sk_sk->sk_stamp = skb->tstamp;
 618	set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); /* there may be more data... */
 619
 620	len  = skb->len - sizeof(struct udphdr);
 621	rqstp->rq_arg.len = len;
 622
 623	rqstp->rq_prot = IPPROTO_UDP;
 624
 625	if (!svc_udp_get_dest_address(rqstp, cmh)) {
 626		net_warn_ratelimited("svc: received unknown control message %d/%d; dropping RPC reply datagram\n",
 627				     cmh->cmsg_level, cmh->cmsg_type);
 628		goto out_free;
 629	}
 630	rqstp->rq_daddrlen = svc_addr_len(svc_daddr(rqstp));
 631
 632	if (skb_is_nonlinear(skb)) {
 633		/* we have to copy */
 634		local_bh_disable();
 635		if (csum_partial_copy_to_xdr(&rqstp->rq_arg, skb)) {
 636			local_bh_enable();
 637			/* checksum error */
 638			goto out_free;
 639		}
 640		local_bh_enable();
 641		skb_free_datagram_locked(svsk->sk_sk, skb);
 642	} else {
 643		/* we can use it in-place */
 644		rqstp->rq_arg.head[0].iov_base = skb->data +
 645			sizeof(struct udphdr);
 646		rqstp->rq_arg.head[0].iov_len = len;
 647		if (skb_checksum_complete(skb))
 648			goto out_free;
 649		rqstp->rq_xprt_ctxt = skb;
 650	}
 651
 652	rqstp->rq_arg.page_base = 0;
 653	if (len <= rqstp->rq_arg.head[0].iov_len) {
 654		rqstp->rq_arg.head[0].iov_len = len;
 655		rqstp->rq_arg.page_len = 0;
 656		rqstp->rq_respages = rqstp->rq_pages+1;
 657	} else {
 658		rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len;
 659		rqstp->rq_respages = rqstp->rq_pages + 1 +
 660			DIV_ROUND_UP(rqstp->rq_arg.page_len, PAGE_SIZE);
 661	}
 662	rqstp->rq_next_page = rqstp->rq_respages+1;
 663
 664	if (serv->sv_stats)
 665		serv->sv_stats->netudpcnt++;
 666
 667	return len;
 668out_free:
 669	trace_kfree_skb(skb, svc_udp_recvfrom);
 670	skb_free_datagram_locked(svsk->sk_sk, skb);
 671	return 0;
 672}
 673
 674static int
 675svc_udp_sendto(struct svc_rqst *rqstp)
 676{
 677	int		error;
 678
 679	error = svc_sendto(rqstp, &rqstp->rq_res);
 680	if (error == -ECONNREFUSED)
 681		/* ICMP error on earlier request. */
 682		error = svc_sendto(rqstp, &rqstp->rq_res);
 683
 684	return error;
 685}
 686
 687static void svc_udp_prep_reply_hdr(struct svc_rqst *rqstp)
 688{
 689}
 690
 691static int svc_udp_has_wspace(struct svc_xprt *xprt)
 692{
 693	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
 694	struct svc_serv	*serv = xprt->xpt_server;
 695	unsigned long required;
 696
 697	/*
 698	 * Set the SOCK_NOSPACE flag before checking the available
 699	 * sock space.
 700	 */
 701	set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
 702	required = atomic_read(&svsk->sk_xprt.xpt_reserved) + serv->sv_max_mesg;
 703	if (required*2 > sock_wspace(svsk->sk_sk))
 704		return 0;
 705	clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
 706	return 1;
 707}
 708
 709static struct svc_xprt *svc_udp_accept(struct svc_xprt *xprt)
 710{
 711	BUG();
 712	return NULL;
 713}
 714
 
 
 
 
 715static struct svc_xprt *svc_udp_create(struct svc_serv *serv,
 716				       struct net *net,
 717				       struct sockaddr *sa, int salen,
 718				       int flags)
 719{
 720	return svc_create_socket(serv, IPPROTO_UDP, net, sa, salen, flags);
 721}
 722
 723static struct svc_xprt_ops svc_udp_ops = {
 724	.xpo_create = svc_udp_create,
 725	.xpo_recvfrom = svc_udp_recvfrom,
 726	.xpo_sendto = svc_udp_sendto,
 727	.xpo_release_rqst = svc_release_skb,
 728	.xpo_detach = svc_sock_detach,
 729	.xpo_free = svc_sock_free,
 730	.xpo_prep_reply_hdr = svc_udp_prep_reply_hdr,
 731	.xpo_has_wspace = svc_udp_has_wspace,
 732	.xpo_accept = svc_udp_accept,
 733	.xpo_secure_port = svc_sock_secure_port,
 
 734};
 735
 736static struct svc_xprt_class svc_udp_class = {
 737	.xcl_name = "udp",
 738	.xcl_owner = THIS_MODULE,
 739	.xcl_ops = &svc_udp_ops,
 740	.xcl_max_payload = RPCSVC_MAXPAYLOAD_UDP,
 741	.xcl_ident = XPRT_TRANSPORT_UDP,
 742};
 743
 744static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv)
 745{
 746	int err, level, optname, one = 1;
 747
 748	svc_xprt_init(sock_net(svsk->sk_sock->sk), &svc_udp_class,
 749		      &svsk->sk_xprt, serv);
 750	clear_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
 751	svsk->sk_sk->sk_data_ready = svc_udp_data_ready;
 752	svsk->sk_sk->sk_write_space = svc_write_space;
 753
 754	/* initialise setting must have enough space to
 755	 * receive and respond to one request.
 756	 * svc_udp_recvfrom will re-adjust if necessary
 757	 */
 758	svc_sock_setbufsize(svsk->sk_sock,
 759			    3 * svsk->sk_xprt.xpt_server->sv_max_mesg,
 760			    3 * svsk->sk_xprt.xpt_server->sv_max_mesg);
 761
 762	/* data might have come in before data_ready set up */
 763	set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 764	set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
 765
 766	/* make sure we get destination address info */
 767	switch (svsk->sk_sk->sk_family) {
 768	case AF_INET:
 769		level = SOL_IP;
 770		optname = IP_PKTINFO;
 771		break;
 772	case AF_INET6:
 773		level = SOL_IPV6;
 774		optname = IPV6_RECVPKTINFO;
 775		break;
 776	default:
 777		BUG();
 778	}
 779	err = kernel_setsockopt(svsk->sk_sock, level, optname,
 780					(char *)&one, sizeof(one));
 781	dprintk("svc: kernel_setsockopt returned %d\n", err);
 782}
 783
 784/*
 785 * A data_ready event on a listening socket means there's a connection
 786 * pending. Do not use state_change as a substitute for it.
 787 */
 788static void svc_tcp_listen_data_ready(struct sock *sk)
 789{
 790	struct svc_sock	*svsk = (struct svc_sock *)sk->sk_user_data;
 791	wait_queue_head_t *wq;
 792
 793	dprintk("svc: socket %p TCP (listen) state change %d\n",
 794		sk, sk->sk_state);
 795
 
 
 
 
 
 
 796	/*
 797	 * This callback may called twice when a new connection
 798	 * is established as a child socket inherits everything
 799	 * from a parent LISTEN socket.
 800	 * 1) data_ready method of the parent socket will be called
 801	 *    when one of child sockets become ESTABLISHED.
 802	 * 2) data_ready method of the child socket may be called
 803	 *    when it receives data before the socket is accepted.
 804	 * In case of 2, we should ignore it silently.
 805	 */
 806	if (sk->sk_state == TCP_LISTEN) {
 807		if (svsk) {
 808			set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
 809			svc_xprt_enqueue(&svsk->sk_xprt);
 810		} else
 811			printk("svc: socket %p: no user data\n", sk);
 812	}
 813
 814	wq = sk_sleep(sk);
 815	if (sunrpc_waitqueue_active(wq))
 816		wake_up_interruptible_all(wq);
 817}
 818
 819/*
 820 * A state change on a connected socket means it's dying or dead.
 821 */
 822static void svc_tcp_state_change(struct sock *sk)
 823{
 824	struct svc_sock	*svsk = (struct svc_sock *)sk->sk_user_data;
 825	wait_queue_head_t *wq = sk_sleep(sk);
 826
 827	dprintk("svc: socket %p TCP (connected) state change %d (svsk %p)\n",
 828		sk, sk->sk_state, sk->sk_user_data);
 829
 830	if (!svsk)
 831		printk("svc: socket %p: no user data\n", sk);
 832	else {
 833		set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
 834		svc_xprt_enqueue(&svsk->sk_xprt);
 835	}
 836	if (sunrpc_waitqueue_active(wq))
 837		wake_up_interruptible_all(wq);
 838}
 839
 840static void svc_tcp_data_ready(struct sock *sk)
 841{
 842	struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
 843	wait_queue_head_t *wq = sk_sleep(sk);
 844
 845	dprintk("svc: socket %p TCP data ready (svsk %p)\n",
 846		sk, sk->sk_user_data);
 847	if (svsk) {
 848		set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 849		svc_xprt_enqueue(&svsk->sk_xprt);
 850	}
 851	if (sunrpc_waitqueue_active(wq))
 852		wake_up_interruptible(wq);
 853}
 854
 855/*
 856 * Accept a TCP connection
 857 */
 858static struct svc_xprt *svc_tcp_accept(struct svc_xprt *xprt)
 859{
 860	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
 861	struct sockaddr_storage addr;
 862	struct sockaddr	*sin = (struct sockaddr *) &addr;
 863	struct svc_serv	*serv = svsk->sk_xprt.xpt_server;
 864	struct socket	*sock = svsk->sk_sock;
 865	struct socket	*newsock;
 866	struct svc_sock	*newsvsk;
 867	int		err, slen;
 868	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
 869
 870	dprintk("svc: tcp_accept %p sock %p\n", svsk, sock);
 871	if (!sock)
 872		return NULL;
 873
 874	clear_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
 875	err = kernel_accept(sock, &newsock, O_NONBLOCK);
 876	if (err < 0) {
 877		if (err == -ENOMEM)
 878			printk(KERN_WARNING "%s: no more sockets!\n",
 879			       serv->sv_name);
 880		else if (err != -EAGAIN)
 881			net_warn_ratelimited("%s: accept failed (err %d)!\n",
 882					     serv->sv_name, -err);
 883		return NULL;
 884	}
 885	set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
 886
 887	err = kernel_getpeername(newsock, sin, &slen);
 888	if (err < 0) {
 889		net_warn_ratelimited("%s: peername failed (err %d)!\n",
 890				     serv->sv_name, -err);
 891		goto failed;		/* aborted connection or whatever */
 892	}
 
 893
 894	/* Ideally, we would want to reject connections from unauthorized
 895	 * hosts here, but when we get encryption, the IP of the host won't
 896	 * tell us anything.  For now just warn about unpriv connections.
 897	 */
 898	if (!svc_port_is_privileged(sin)) {
 899		dprintk("%s: connect from unprivileged port: %s\n",
 900			serv->sv_name,
 901			__svc_print_addr(sin, buf, sizeof(buf)));
 902	}
 903	dprintk("%s: connect from %s\n", serv->sv_name,
 904		__svc_print_addr(sin, buf, sizeof(buf)));
 905
 
 
 
 
 
 906	/* make sure that a write doesn't block forever when
 907	 * low on memory
 908	 */
 909	newsock->sk->sk_sndtimeo = HZ*30;
 910
 911	newsvsk = svc_setup_socket(serv, newsock,
 912				 (SVC_SOCK_ANONYMOUS | SVC_SOCK_TEMPORARY));
 913	if (IS_ERR(newsvsk))
 914		goto failed;
 915	svc_xprt_set_remote(&newsvsk->sk_xprt, sin, slen);
 916	err = kernel_getsockname(newsock, sin, &slen);
 
 917	if (unlikely(err < 0)) {
 918		dprintk("svc_tcp_accept: kernel_getsockname error %d\n", -err);
 919		slen = offsetof(struct sockaddr, sa_data);
 920	}
 921	svc_xprt_set_local(&newsvsk->sk_xprt, sin, slen);
 922
 923	if (sock_is_loopback(newsock->sk))
 924		set_bit(XPT_LOCAL, &newsvsk->sk_xprt.xpt_flags);
 925	else
 926		clear_bit(XPT_LOCAL, &newsvsk->sk_xprt.xpt_flags);
 927	if (serv->sv_stats)
 928		serv->sv_stats->nettcpconn++;
 929
 930	return &newsvsk->sk_xprt;
 931
 932failed:
 933	sock_release(newsock);
 934	return NULL;
 935}
 936
 937static unsigned int svc_tcp_restore_pages(struct svc_sock *svsk, struct svc_rqst *rqstp)
 938{
 939	unsigned int i, len, npages;
 940
 941	if (svsk->sk_datalen == 0)
 942		return 0;
 943	len = svsk->sk_datalen;
 944	npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
 945	for (i = 0; i < npages; i++) {
 946		if (rqstp->rq_pages[i] != NULL)
 947			put_page(rqstp->rq_pages[i]);
 948		BUG_ON(svsk->sk_pages[i] == NULL);
 949		rqstp->rq_pages[i] = svsk->sk_pages[i];
 950		svsk->sk_pages[i] = NULL;
 951	}
 952	rqstp->rq_arg.head[0].iov_base = page_address(rqstp->rq_pages[0]);
 953	return len;
 954}
 955
 956static void svc_tcp_save_pages(struct svc_sock *svsk, struct svc_rqst *rqstp)
 957{
 958	unsigned int i, len, npages;
 959
 960	if (svsk->sk_datalen == 0)
 961		return;
 962	len = svsk->sk_datalen;
 963	npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
 964	for (i = 0; i < npages; i++) {
 965		svsk->sk_pages[i] = rqstp->rq_pages[i];
 966		rqstp->rq_pages[i] = NULL;
 967	}
 968}
 969
 970static void svc_tcp_clear_pages(struct svc_sock *svsk)
 971{
 972	unsigned int i, len, npages;
 973
 974	if (svsk->sk_datalen == 0)
 975		goto out;
 976	len = svsk->sk_datalen;
 977	npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
 978	for (i = 0; i < npages; i++) {
 979		if (svsk->sk_pages[i] == NULL) {
 980			WARN_ON_ONCE(1);
 981			continue;
 982		}
 983		put_page(svsk->sk_pages[i]);
 984		svsk->sk_pages[i] = NULL;
 985	}
 986out:
 987	svsk->sk_tcplen = 0;
 988	svsk->sk_datalen = 0;
 989}
 990
 991/*
 992 * Receive fragment record header.
 993 * If we haven't gotten the record length yet, get the next four bytes.
 994 */
 995static int svc_tcp_recv_record(struct svc_sock *svsk, struct svc_rqst *rqstp)
 996{
 997	struct svc_serv	*serv = svsk->sk_xprt.xpt_server;
 998	unsigned int want;
 999	int len;
1000
1001	if (svsk->sk_tcplen < sizeof(rpc_fraghdr)) {
1002		struct kvec	iov;
1003
1004		want = sizeof(rpc_fraghdr) - svsk->sk_tcplen;
1005		iov.iov_base = ((char *) &svsk->sk_reclen) + svsk->sk_tcplen;
1006		iov.iov_len  = want;
1007		if ((len = svc_recvfrom(rqstp, &iov, 1, want)) < 0)
 
1008			goto error;
1009		svsk->sk_tcplen += len;
1010
1011		if (len < want) {
1012			dprintk("svc: short recvfrom while reading record "
1013				"length (%d of %d)\n", len, want);
1014			return -EAGAIN;
1015		}
1016
1017		dprintk("svc: TCP record, %d bytes\n", svc_sock_reclen(svsk));
1018		if (svc_sock_reclen(svsk) + svsk->sk_datalen >
1019							serv->sv_max_mesg) {
1020			net_notice_ratelimited("RPC: fragment too large: %d\n",
1021					svc_sock_reclen(svsk));
1022			goto err_delete;
1023		}
1024	}
1025
1026	return svc_sock_reclen(svsk);
1027error:
1028	dprintk("RPC: TCP recv_record got %d\n", len);
1029	return len;
1030err_delete:
1031	set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1032	return -EAGAIN;
1033}
1034
1035static int receive_cb_reply(struct svc_sock *svsk, struct svc_rqst *rqstp)
1036{
1037	struct rpc_xprt *bc_xprt = svsk->sk_xprt.xpt_bc_xprt;
1038	struct rpc_rqst *req = NULL;
1039	struct kvec *src, *dst;
1040	__be32 *p = (__be32 *)rqstp->rq_arg.head[0].iov_base;
1041	__be32 xid;
1042	__be32 calldir;
1043
1044	xid = *p++;
1045	calldir = *p;
1046
1047	if (!bc_xprt)
1048		return -EAGAIN;
1049	spin_lock_bh(&bc_xprt->transport_lock);
1050	req = xprt_lookup_rqst(bc_xprt, xid);
1051	if (!req)
1052		goto unlock_notfound;
1053
1054	memcpy(&req->rq_private_buf, &req->rq_rcv_buf, sizeof(struct xdr_buf));
1055	/*
1056	 * XXX!: cheating for now!  Only copying HEAD.
1057	 * But we know this is good enough for now (in fact, for any
1058	 * callback reply in the forseeable future).
1059	 */
1060	dst = &req->rq_private_buf.head[0];
1061	src = &rqstp->rq_arg.head[0];
1062	if (dst->iov_len < src->iov_len)
1063		goto unlock_eagain; /* whatever; just giving up. */
1064	memcpy(dst->iov_base, src->iov_base, src->iov_len);
1065	xprt_complete_rqst(req->rq_task, rqstp->rq_arg.len);
1066	rqstp->rq_arg.len = 0;
1067	spin_unlock_bh(&bc_xprt->transport_lock);
1068	return 0;
1069unlock_notfound:
1070	printk(KERN_NOTICE
1071		"%s: Got unrecognized reply: "
1072		"calldir 0x%x xpt_bc_xprt %p xid %08x\n",
1073		__func__, ntohl(calldir),
1074		bc_xprt, ntohl(xid));
1075unlock_eagain:
1076	spin_unlock_bh(&bc_xprt->transport_lock);
1077	return -EAGAIN;
1078}
1079
1080static int copy_pages_to_kvecs(struct kvec *vec, struct page **pages, int len)
1081{
1082	int i = 0;
1083	int t = 0;
1084
1085	while (t < len) {
1086		vec[i].iov_base = page_address(pages[i]);
1087		vec[i].iov_len = PAGE_SIZE;
1088		i++;
1089		t += PAGE_SIZE;
1090	}
1091	return i;
1092}
1093
1094static void svc_tcp_fragment_received(struct svc_sock *svsk)
1095{
1096	/* If we have more data, signal svc_xprt_enqueue() to try again */
1097	dprintk("svc: TCP %s record (%d bytes)\n",
1098		svc_sock_final_rec(svsk) ? "final" : "nonfinal",
1099		svc_sock_reclen(svsk));
1100	svsk->sk_tcplen = 0;
1101	svsk->sk_reclen = 0;
1102}
1103
1104/*
1105 * Receive data from a TCP socket.
1106 */
1107static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
1108{
1109	struct svc_sock	*svsk =
1110		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
1111	struct svc_serv	*serv = svsk->sk_xprt.xpt_server;
1112	int		len;
1113	struct kvec *vec;
1114	unsigned int want, base;
1115	__be32 *p;
1116	__be32 calldir;
1117	int pnum;
1118
1119	dprintk("svc: tcp_recv %p data %d conn %d close %d\n",
1120		svsk, test_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags),
1121		test_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags),
1122		test_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags));
1123
1124	len = svc_tcp_recv_record(svsk, rqstp);
1125	if (len < 0)
1126		goto error;
1127
1128	base = svc_tcp_restore_pages(svsk, rqstp);
1129	want = svc_sock_reclen(svsk) - (svsk->sk_tcplen - sizeof(rpc_fraghdr));
1130
1131	vec = rqstp->rq_vec;
1132
1133	pnum = copy_pages_to_kvecs(&vec[0], &rqstp->rq_pages[0],
1134						svsk->sk_datalen + want);
1135
1136	rqstp->rq_respages = &rqstp->rq_pages[pnum];
1137	rqstp->rq_next_page = rqstp->rq_respages + 1;
1138
1139	/* Now receive data */
1140	len = svc_partial_recvfrom(rqstp, vec, pnum, want, base);
1141	if (len >= 0) {
1142		svsk->sk_tcplen += len;
1143		svsk->sk_datalen += len;
1144	}
1145	if (len != want || !svc_sock_final_rec(svsk)) {
1146		svc_tcp_save_pages(svsk, rqstp);
1147		if (len < 0 && len != -EAGAIN)
1148			goto err_delete;
1149		if (len == want)
1150			svc_tcp_fragment_received(svsk);
1151		else
1152			dprintk("svc: incomplete TCP record (%d of %d)\n",
1153				(int)(svsk->sk_tcplen - sizeof(rpc_fraghdr)),
1154				svc_sock_reclen(svsk));
1155		goto err_noclose;
1156	}
1157
1158	if (svsk->sk_datalen < 8) {
1159		svsk->sk_datalen = 0;
1160		goto err_delete; /* client is nuts. */
1161	}
1162
1163	rqstp->rq_arg.len = svsk->sk_datalen;
1164	rqstp->rq_arg.page_base = 0;
1165	if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len) {
1166		rqstp->rq_arg.head[0].iov_len = rqstp->rq_arg.len;
1167		rqstp->rq_arg.page_len = 0;
1168	} else
1169		rqstp->rq_arg.page_len = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len;
1170
1171	rqstp->rq_xprt_ctxt   = NULL;
1172	rqstp->rq_prot	      = IPPROTO_TCP;
1173	if (test_bit(XPT_LOCAL, &svsk->sk_xprt.xpt_flags))
1174		set_bit(RQ_LOCAL, &rqstp->rq_flags);
1175	else
1176		clear_bit(RQ_LOCAL, &rqstp->rq_flags);
1177
1178	p = (__be32 *)rqstp->rq_arg.head[0].iov_base;
1179	calldir = p[1];
1180	if (calldir)
1181		len = receive_cb_reply(svsk, rqstp);
1182
1183	/* Reset TCP read info */
1184	svsk->sk_datalen = 0;
1185	svc_tcp_fragment_received(svsk);
1186
1187	if (len < 0)
1188		goto error;
1189
1190	svc_xprt_copy_addrs(rqstp, &svsk->sk_xprt);
1191	if (serv->sv_stats)
1192		serv->sv_stats->nettcpcnt++;
1193
1194	return rqstp->rq_arg.len;
1195
1196error:
1197	if (len != -EAGAIN)
1198		goto err_delete;
1199	dprintk("RPC: TCP recvfrom got EAGAIN\n");
1200	return 0;
1201err_delete:
1202	printk(KERN_NOTICE "%s: recvfrom returned errno %d\n",
1203	       svsk->sk_xprt.xpt_server->sv_name, -len);
1204	set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1205err_noclose:
1206	return 0;	/* record not complete */
1207}
1208
1209/*
1210 * Send out data on TCP socket.
1211 */
1212static int svc_tcp_sendto(struct svc_rqst *rqstp)
1213{
1214	struct xdr_buf	*xbufp = &rqstp->rq_res;
1215	int sent;
1216	__be32 reclen;
1217
1218	/* Set up the first element of the reply kvec.
1219	 * Any other kvecs that may be in use have been taken
1220	 * care of by the server implementation itself.
1221	 */
1222	reclen = htonl(0x80000000|((xbufp->len ) - 4));
1223	memcpy(xbufp->head[0].iov_base, &reclen, 4);
1224
1225	sent = svc_sendto(rqstp, &rqstp->rq_res);
1226	if (sent != xbufp->len) {
1227		printk(KERN_NOTICE
1228		       "rpc-srv/tcp: %s: %s %d when sending %d bytes "
1229		       "- shutting down socket\n",
1230		       rqstp->rq_xprt->xpt_server->sv_name,
1231		       (sent<0)?"got error":"sent only",
1232		       sent, xbufp->len);
1233		set_bit(XPT_CLOSE, &rqstp->rq_xprt->xpt_flags);
1234		svc_xprt_enqueue(rqstp->rq_xprt);
1235		sent = -EAGAIN;
1236	}
1237	return sent;
1238}
1239
1240/*
1241 * Setup response header. TCP has a 4B record length field.
1242 */
1243static void svc_tcp_prep_reply_hdr(struct svc_rqst *rqstp)
1244{
1245	struct kvec *resv = &rqstp->rq_res.head[0];
1246
1247	/* tcp needs a space for the record length... */
1248	svc_putnl(resv, 0);
1249}
1250
1251static struct svc_xprt *svc_tcp_create(struct svc_serv *serv,
1252				       struct net *net,
1253				       struct sockaddr *sa, int salen,
1254				       int flags)
1255{
1256	return svc_create_socket(serv, IPPROTO_TCP, net, sa, salen, flags);
1257}
1258
1259#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1260static struct svc_xprt *svc_bc_create_socket(struct svc_serv *, int,
1261					     struct net *, struct sockaddr *,
1262					     int, int);
1263static void svc_bc_sock_free(struct svc_xprt *xprt);
1264
1265static struct svc_xprt *svc_bc_tcp_create(struct svc_serv *serv,
1266				       struct net *net,
1267				       struct sockaddr *sa, int salen,
1268				       int flags)
1269{
1270	return svc_bc_create_socket(serv, IPPROTO_TCP, net, sa, salen, flags);
1271}
1272
1273static void svc_bc_tcp_sock_detach(struct svc_xprt *xprt)
1274{
1275}
1276
1277static struct svc_xprt_ops svc_tcp_bc_ops = {
1278	.xpo_create = svc_bc_tcp_create,
1279	.xpo_detach = svc_bc_tcp_sock_detach,
1280	.xpo_free = svc_bc_sock_free,
1281	.xpo_prep_reply_hdr = svc_tcp_prep_reply_hdr,
1282	.xpo_secure_port = svc_sock_secure_port,
1283};
1284
1285static struct svc_xprt_class svc_tcp_bc_class = {
1286	.xcl_name = "tcp-bc",
1287	.xcl_owner = THIS_MODULE,
1288	.xcl_ops = &svc_tcp_bc_ops,
1289	.xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP,
1290};
1291
1292static void svc_init_bc_xprt_sock(void)
1293{
1294	svc_reg_xprt_class(&svc_tcp_bc_class);
1295}
1296
1297static void svc_cleanup_bc_xprt_sock(void)
1298{
1299	svc_unreg_xprt_class(&svc_tcp_bc_class);
1300}
1301#else /* CONFIG_SUNRPC_BACKCHANNEL */
1302static void svc_init_bc_xprt_sock(void)
1303{
1304}
1305
1306static void svc_cleanup_bc_xprt_sock(void)
1307{
1308}
1309#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1310
1311static struct svc_xprt_ops svc_tcp_ops = {
1312	.xpo_create = svc_tcp_create,
1313	.xpo_recvfrom = svc_tcp_recvfrom,
1314	.xpo_sendto = svc_tcp_sendto,
1315	.xpo_release_rqst = svc_release_skb,
1316	.xpo_detach = svc_tcp_sock_detach,
1317	.xpo_free = svc_sock_free,
1318	.xpo_prep_reply_hdr = svc_tcp_prep_reply_hdr,
1319	.xpo_has_wspace = svc_tcp_has_wspace,
1320	.xpo_accept = svc_tcp_accept,
1321	.xpo_secure_port = svc_sock_secure_port,
1322	.xpo_adjust_wspace = svc_tcp_adjust_wspace,
1323};
1324
1325static struct svc_xprt_class svc_tcp_class = {
1326	.xcl_name = "tcp",
1327	.xcl_owner = THIS_MODULE,
1328	.xcl_ops = &svc_tcp_ops,
1329	.xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP,
1330	.xcl_ident = XPRT_TRANSPORT_TCP,
1331};
1332
1333void svc_init_xprt_sock(void)
1334{
1335	svc_reg_xprt_class(&svc_tcp_class);
1336	svc_reg_xprt_class(&svc_udp_class);
1337	svc_init_bc_xprt_sock();
1338}
1339
1340void svc_cleanup_xprt_sock(void)
1341{
1342	svc_unreg_xprt_class(&svc_tcp_class);
1343	svc_unreg_xprt_class(&svc_udp_class);
1344	svc_cleanup_bc_xprt_sock();
1345}
1346
1347static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv)
1348{
1349	struct sock	*sk = svsk->sk_sk;
1350
1351	svc_xprt_init(sock_net(svsk->sk_sock->sk), &svc_tcp_class,
1352		      &svsk->sk_xprt, serv);
1353	set_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
 
1354	if (sk->sk_state == TCP_LISTEN) {
1355		dprintk("setting up TCP socket for listening\n");
 
1356		set_bit(XPT_LISTENER, &svsk->sk_xprt.xpt_flags);
1357		sk->sk_data_ready = svc_tcp_listen_data_ready;
1358		set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
1359	} else {
1360		dprintk("setting up TCP socket for reading\n");
1361		sk->sk_state_change = svc_tcp_state_change;
1362		sk->sk_data_ready = svc_tcp_data_ready;
1363		sk->sk_write_space = svc_tcp_write_space;
1364
1365		svsk->sk_reclen = 0;
1366		svsk->sk_tcplen = 0;
1367		svsk->sk_datalen = 0;
1368		memset(&svsk->sk_pages[0], 0, sizeof(svsk->sk_pages));
1369
1370		tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
1371
1372		set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
1373		if (sk->sk_state != TCP_ESTABLISHED)
 
 
 
 
1374			set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
 
1375	}
1376}
1377
1378void svc_sock_update_bufs(struct svc_serv *serv)
1379{
1380	/*
1381	 * The number of server threads has changed. Update
1382	 * rcvbuf and sndbuf accordingly on all sockets
1383	 */
1384	struct svc_sock *svsk;
1385
1386	spin_lock_bh(&serv->sv_lock);
1387	list_for_each_entry(svsk, &serv->sv_permsocks, sk_xprt.xpt_list)
1388		set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
1389	spin_unlock_bh(&serv->sv_lock);
1390}
1391EXPORT_SYMBOL_GPL(svc_sock_update_bufs);
1392
1393/*
1394 * Initialize socket for RPC use and create svc_sock struct
1395 */
1396static struct svc_sock *svc_setup_socket(struct svc_serv *serv,
1397						struct socket *sock,
1398						int flags)
1399{
1400	struct svc_sock	*svsk;
1401	struct sock	*inet;
1402	int		pmap_register = !(flags & SVC_SOCK_ANONYMOUS);
1403	int		err = 0;
1404
1405	dprintk("svc: svc_setup_socket %p\n", sock);
1406	svsk = kzalloc(sizeof(*svsk), GFP_KERNEL);
1407	if (!svsk)
1408		return ERR_PTR(-ENOMEM);
1409
1410	inet = sock->sk;
1411
1412	/* Register socket with portmapper */
1413	if (pmap_register)
1414		err = svc_register(serv, sock_net(sock->sk), inet->sk_family,
1415				     inet->sk_protocol,
1416				     ntohs(inet_sk(inet)->inet_sport));
1417
1418	if (err < 0) {
1419		kfree(svsk);
1420		return ERR_PTR(err);
1421	}
1422
1423	inet->sk_user_data = svsk;
1424	svsk->sk_sock = sock;
1425	svsk->sk_sk = inet;
1426	svsk->sk_ostate = inet->sk_state_change;
1427	svsk->sk_odata = inet->sk_data_ready;
1428	svsk->sk_owspace = inet->sk_write_space;
 
 
 
 
 
 
 
1429
1430	/* Initialize the socket */
1431	if (sock->type == SOCK_DGRAM)
1432		svc_udp_init(svsk, serv);
1433	else {
1434		/* initialise setting must have enough space to
1435		 * receive and respond to one request.
1436		 */
1437		svc_sock_setbufsize(svsk->sk_sock, 4 * serv->sv_max_mesg,
1438					4 * serv->sv_max_mesg);
1439		svc_tcp_init(svsk, serv);
1440	}
1441
1442	dprintk("svc: svc_setup_socket created %p (inet %p)\n",
1443				svsk, svsk->sk_sk);
 
 
 
1444
1445	return svsk;
1446}
1447
1448bool svc_alien_sock(struct net *net, int fd)
1449{
1450	int err;
1451	struct socket *sock = sockfd_lookup(fd, &err);
1452	bool ret = false;
1453
1454	if (!sock)
1455		goto out;
1456	if (sock_net(sock->sk) != net)
1457		ret = true;
1458	sockfd_put(sock);
1459out:
1460	return ret;
1461}
1462EXPORT_SYMBOL_GPL(svc_alien_sock);
1463
1464/**
1465 * svc_addsock - add a listener socket to an RPC service
1466 * @serv: pointer to RPC service to which to add a new listener
1467 * @fd: file descriptor of the new listener
1468 * @name_return: pointer to buffer to fill in with name of listener
1469 * @len: size of the buffer
 
1470 *
1471 * Fills in socket name and returns positive length of name if successful.
1472 * Name is terminated with '\n'.  On error, returns a negative errno
1473 * value.
1474 */
1475int svc_addsock(struct svc_serv *serv, const int fd, char *name_return,
1476		const size_t len)
1477{
1478	int err = 0;
1479	struct socket *so = sockfd_lookup(fd, &err);
1480	struct svc_sock *svsk = NULL;
1481	struct sockaddr_storage addr;
1482	struct sockaddr *sin = (struct sockaddr *)&addr;
1483	int salen;
1484
1485	if (!so)
1486		return err;
1487	err = -EAFNOSUPPORT;
1488	if ((so->sk->sk_family != PF_INET) && (so->sk->sk_family != PF_INET6))
1489		goto out;
1490	err =  -EPROTONOSUPPORT;
1491	if (so->sk->sk_protocol != IPPROTO_TCP &&
1492	    so->sk->sk_protocol != IPPROTO_UDP)
1493		goto out;
1494	err = -EISCONN;
1495	if (so->state > SS_UNCONNECTED)
1496		goto out;
1497	err = -ENOENT;
1498	if (!try_module_get(THIS_MODULE))
1499		goto out;
1500	svsk = svc_setup_socket(serv, so, SVC_SOCK_DEFAULTS);
1501	if (IS_ERR(svsk)) {
1502		module_put(THIS_MODULE);
1503		err = PTR_ERR(svsk);
1504		goto out;
1505	}
1506	if (kernel_getsockname(svsk->sk_sock, sin, &salen) == 0)
 
1507		svc_xprt_set_local(&svsk->sk_xprt, sin, salen);
 
1508	svc_add_new_perm_xprt(serv, &svsk->sk_xprt);
1509	return svc_one_sock_name(svsk, name_return, len);
1510out:
1511	sockfd_put(so);
1512	return err;
1513}
1514EXPORT_SYMBOL_GPL(svc_addsock);
1515
1516/*
1517 * Create socket for RPC service.
1518 */
1519static struct svc_xprt *svc_create_socket(struct svc_serv *serv,
1520					  int protocol,
1521					  struct net *net,
1522					  struct sockaddr *sin, int len,
1523					  int flags)
1524{
1525	struct svc_sock	*svsk;
1526	struct socket	*sock;
1527	int		error;
1528	int		type;
1529	struct sockaddr_storage addr;
1530	struct sockaddr *newsin = (struct sockaddr *)&addr;
1531	int		newlen;
1532	int		family;
1533	int		val;
1534	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
1535
1536	dprintk("svc: svc_create_socket(%s, %d, %s)\n",
1537			serv->sv_program->pg_name, protocol,
1538			__svc_print_addr(sin, buf, sizeof(buf)));
1539
1540	if (protocol != IPPROTO_UDP && protocol != IPPROTO_TCP) {
1541		printk(KERN_WARNING "svc: only UDP and TCP "
1542				"sockets supported\n");
1543		return ERR_PTR(-EINVAL);
1544	}
1545
1546	type = (protocol == IPPROTO_UDP)? SOCK_DGRAM : SOCK_STREAM;
1547	switch (sin->sa_family) {
1548	case AF_INET6:
1549		family = PF_INET6;
1550		break;
1551	case AF_INET:
1552		family = PF_INET;
1553		break;
1554	default:
1555		return ERR_PTR(-EINVAL);
1556	}
1557
1558	error = __sock_create(net, family, type, protocol, &sock, 1);
1559	if (error < 0)
1560		return ERR_PTR(error);
1561
1562	svc_reclassify_socket(sock);
1563
1564	/*
1565	 * If this is an PF_INET6 listener, we want to avoid
1566	 * getting requests from IPv4 remotes.  Those should
1567	 * be shunted to a PF_INET listener via rpcbind.
1568	 */
1569	val = 1;
1570	if (family == PF_INET6)
1571		kernel_setsockopt(sock, SOL_IPV6, IPV6_V6ONLY,
1572					(char *)&val, sizeof(val));
1573
1574	if (type == SOCK_STREAM)
1575		sock->sk->sk_reuse = SK_CAN_REUSE; /* allow address reuse */
1576	error = kernel_bind(sock, sin, len);
1577	if (error < 0)
1578		goto bummer;
1579
1580	newlen = len;
1581	error = kernel_getsockname(sock, newsin, &newlen);
1582	if (error < 0)
1583		goto bummer;
 
1584
1585	if (protocol == IPPROTO_TCP) {
1586		if ((error = kernel_listen(sock, 64)) < 0)
1587			goto bummer;
1588	}
1589
1590	svsk = svc_setup_socket(serv, sock, flags);
1591	if (IS_ERR(svsk)) {
1592		error = PTR_ERR(svsk);
1593		goto bummer;
1594	}
1595	svc_xprt_set_local(&svsk->sk_xprt, newsin, newlen);
1596	return (struct svc_xprt *)svsk;
1597bummer:
1598	dprintk("svc: svc_create_socket error = %d\n", -error);
1599	sock_release(sock);
1600	return ERR_PTR(error);
1601}
1602
1603/*
1604 * Detach the svc_sock from the socket so that no
1605 * more callbacks occur.
1606 */
1607static void svc_sock_detach(struct svc_xprt *xprt)
1608{
1609	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1610	struct sock *sk = svsk->sk_sk;
1611	wait_queue_head_t *wq;
1612
1613	dprintk("svc: svc_sock_detach(%p)\n", svsk);
1614
1615	/* put back the old socket callbacks */
 
1616	sk->sk_state_change = svsk->sk_ostate;
1617	sk->sk_data_ready = svsk->sk_odata;
1618	sk->sk_write_space = svsk->sk_owspace;
1619
1620	wq = sk_sleep(sk);
1621	if (sunrpc_waitqueue_active(wq))
1622		wake_up_interruptible(wq);
1623}
1624
1625/*
1626 * Disconnect the socket, and reset the callbacks
1627 */
1628static void svc_tcp_sock_detach(struct svc_xprt *xprt)
1629{
1630	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1631
1632	dprintk("svc: svc_tcp_sock_detach(%p)\n", svsk);
1633
1634	svc_sock_detach(xprt);
1635
1636	if (!test_bit(XPT_LISTENER, &xprt->xpt_flags)) {
1637		svc_tcp_clear_pages(svsk);
1638		kernel_sock_shutdown(svsk->sk_sock, SHUT_RDWR);
1639	}
1640}
1641
1642/*
1643 * Free the svc_sock's socket resources and the svc_sock itself.
1644 */
1645static void svc_sock_free(struct svc_xprt *xprt)
1646{
1647	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1648	dprintk("svc: svc_sock_free(%p)\n", svsk);
1649
1650	if (svsk->sk_sock->file)
1651		sockfd_put(svsk->sk_sock);
1652	else
1653		sock_release(svsk->sk_sock);
1654	kfree(svsk);
1655}
1656
1657#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1658/*
1659 * Create a back channel svc_xprt which shares the fore channel socket.
1660 */
1661static struct svc_xprt *svc_bc_create_socket(struct svc_serv *serv,
1662					     int protocol,
1663					     struct net *net,
1664					     struct sockaddr *sin, int len,
1665					     int flags)
1666{
1667	struct svc_sock *svsk;
1668	struct svc_xprt *xprt;
1669
1670	if (protocol != IPPROTO_TCP) {
1671		printk(KERN_WARNING "svc: only TCP sockets"
1672			" supported on shared back channel\n");
1673		return ERR_PTR(-EINVAL);
1674	}
1675
1676	svsk = kzalloc(sizeof(*svsk), GFP_KERNEL);
1677	if (!svsk)
1678		return ERR_PTR(-ENOMEM);
1679
1680	xprt = &svsk->sk_xprt;
1681	svc_xprt_init(net, &svc_tcp_bc_class, xprt, serv);
1682
1683	serv->sv_bc_xprt = xprt;
1684
1685	return xprt;
1686}
1687
1688/*
1689 * Free a back channel svc_sock.
1690 */
1691static void svc_bc_sock_free(struct svc_xprt *xprt)
1692{
1693	if (xprt)
1694		kfree(container_of(xprt, struct svc_sock, sk_xprt));
1695}
1696#endif /* CONFIG_SUNRPC_BACKCHANNEL */