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v3.1
   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/errno.h>
  25#include <linux/fcntl.h>
  26#include <linux/net.h>
  27#include <linux/in.h>
  28#include <linux/inet.h>
  29#include <linux/udp.h>
  30#include <linux/tcp.h>
  31#include <linux/unistd.h>
  32#include <linux/slab.h>
  33#include <linux/netdevice.h>
  34#include <linux/skbuff.h>
  35#include <linux/file.h>
  36#include <linux/freezer.h>
  37#include <net/sock.h>
  38#include <net/checksum.h>
  39#include <net/ip.h>
  40#include <net/ipv6.h>
  41#include <net/tcp.h>
  42#include <net/tcp_states.h>
  43#include <asm/uaccess.h>
  44#include <asm/ioctls.h>
  45
  46#include <linux/sunrpc/types.h>
  47#include <linux/sunrpc/clnt.h>
  48#include <linux/sunrpc/xdr.h>
  49#include <linux/sunrpc/msg_prot.h>
  50#include <linux/sunrpc/svcsock.h>
  51#include <linux/sunrpc/stats.h>
  52#include <linux/sunrpc/xprt.h>
  53
  54#include "sunrpc.h"
  55
  56#define RPCDBG_FACILITY	RPCDBG_SVCXPRT
  57
  58
  59static struct svc_sock *svc_setup_socket(struct svc_serv *, struct socket *,
  60					 int *errp, int flags);
  61static void		svc_udp_data_ready(struct sock *, int);
  62static int		svc_udp_recvfrom(struct svc_rqst *);
  63static int		svc_udp_sendto(struct svc_rqst *);
  64static void		svc_sock_detach(struct svc_xprt *);
  65static void		svc_tcp_sock_detach(struct svc_xprt *);
  66static void		svc_sock_free(struct svc_xprt *);
  67
  68static struct svc_xprt *svc_create_socket(struct svc_serv *, int,
  69					  struct net *, struct sockaddr *,
  70					  int, int);
  71#if defined(CONFIG_SUNRPC_BACKCHANNEL)
  72static struct svc_xprt *svc_bc_create_socket(struct svc_serv *, int,
  73					     struct net *, struct sockaddr *,
  74					     int, int);
  75static void svc_bc_sock_free(struct svc_xprt *xprt);
  76#endif /* CONFIG_SUNRPC_BACKCHANNEL */
  77
  78#ifdef CONFIG_DEBUG_LOCK_ALLOC
  79static struct lock_class_key svc_key[2];
  80static struct lock_class_key svc_slock_key[2];
  81
  82static void svc_reclassify_socket(struct socket *sock)
  83{
  84	struct sock *sk = sock->sk;
  85	BUG_ON(sock_owned_by_user(sk));
  86	switch (sk->sk_family) {
  87	case AF_INET:
  88		sock_lock_init_class_and_name(sk, "slock-AF_INET-NFSD",
  89					      &svc_slock_key[0],
  90					      "sk_xprt.xpt_lock-AF_INET-NFSD",
  91					      &svc_key[0]);
  92		break;
  93
  94	case AF_INET6:
  95		sock_lock_init_class_and_name(sk, "slock-AF_INET6-NFSD",
  96					      &svc_slock_key[1],
  97					      "sk_xprt.xpt_lock-AF_INET6-NFSD",
  98					      &svc_key[1]);
  99		break;
 100
 101	default:
 102		BUG();
 103	}
 104}
 105#else
 106static void svc_reclassify_socket(struct socket *sock)
 107{
 108}
 109#endif
 110
 111/*
 112 * Release an skbuff after use
 113 */
 114static void svc_release_skb(struct svc_rqst *rqstp)
 115{
 116	struct sk_buff *skb = rqstp->rq_xprt_ctxt;
 117
 118	if (skb) {
 119		struct svc_sock *svsk =
 120			container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 121		rqstp->rq_xprt_ctxt = NULL;
 122
 123		dprintk("svc: service %p, releasing skb %p\n", rqstp, skb);
 124		skb_free_datagram_locked(svsk->sk_sk, skb);
 125	}
 126}
 127
 128union svc_pktinfo_u {
 129	struct in_pktinfo pkti;
 130	struct in6_pktinfo pkti6;
 131};
 132#define SVC_PKTINFO_SPACE \
 133	CMSG_SPACE(sizeof(union svc_pktinfo_u))
 134
 135static void svc_set_cmsg_data(struct svc_rqst *rqstp, struct cmsghdr *cmh)
 136{
 137	struct svc_sock *svsk =
 138		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 139	switch (svsk->sk_sk->sk_family) {
 140	case AF_INET: {
 141			struct in_pktinfo *pki = CMSG_DATA(cmh);
 142
 143			cmh->cmsg_level = SOL_IP;
 144			cmh->cmsg_type = IP_PKTINFO;
 145			pki->ipi_ifindex = 0;
 146			pki->ipi_spec_dst.s_addr = rqstp->rq_daddr.addr.s_addr;
 
 147			cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
 148		}
 149		break;
 150
 151	case AF_INET6: {
 152			struct in6_pktinfo *pki = CMSG_DATA(cmh);
 
 153
 154			cmh->cmsg_level = SOL_IPV6;
 155			cmh->cmsg_type = IPV6_PKTINFO;
 156			pki->ipi6_ifindex = 0;
 157			ipv6_addr_copy(&pki->ipi6_addr,
 158					&rqstp->rq_daddr.addr6);
 159			cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
 160		}
 161		break;
 162	}
 163}
 164
 165/*
 166 * send routine intended to be shared by the fore- and back-channel
 167 */
 168int svc_send_common(struct socket *sock, struct xdr_buf *xdr,
 169		    struct page *headpage, unsigned long headoffset,
 170		    struct page *tailpage, unsigned long tailoffset)
 171{
 172	int		result;
 173	int		size;
 174	struct page	**ppage = xdr->pages;
 175	size_t		base = xdr->page_base;
 176	unsigned int	pglen = xdr->page_len;
 177	unsigned int	flags = MSG_MORE;
 178	int		slen;
 179	int		len = 0;
 180
 181	slen = xdr->len;
 182
 183	/* send head */
 184	if (slen == xdr->head[0].iov_len)
 185		flags = 0;
 186	len = kernel_sendpage(sock, headpage, headoffset,
 187				  xdr->head[0].iov_len, flags);
 188	if (len != xdr->head[0].iov_len)
 189		goto out;
 190	slen -= xdr->head[0].iov_len;
 191	if (slen == 0)
 192		goto out;
 193
 194	/* send page data */
 195	size = PAGE_SIZE - base < pglen ? PAGE_SIZE - base : pglen;
 196	while (pglen > 0) {
 197		if (slen == size)
 198			flags = 0;
 199		result = kernel_sendpage(sock, *ppage, base, size, flags);
 200		if (result > 0)
 201			len += result;
 202		if (result != size)
 203			goto out;
 204		slen -= size;
 205		pglen -= size;
 206		size = PAGE_SIZE < pglen ? PAGE_SIZE : pglen;
 207		base = 0;
 208		ppage++;
 209	}
 210
 211	/* send tail */
 212	if (xdr->tail[0].iov_len) {
 213		result = kernel_sendpage(sock, tailpage, tailoffset,
 214				   xdr->tail[0].iov_len, 0);
 215		if (result > 0)
 216			len += result;
 217	}
 218
 219out:
 220	return len;
 221}
 222
 223
 224/*
 225 * Generic sendto routine
 226 */
 227static int svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr)
 228{
 229	struct svc_sock	*svsk =
 230		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 231	struct socket	*sock = svsk->sk_sock;
 232	union {
 233		struct cmsghdr	hdr;
 234		long		all[SVC_PKTINFO_SPACE / sizeof(long)];
 235	} buffer;
 236	struct cmsghdr *cmh = &buffer.hdr;
 237	int		len = 0;
 238	unsigned long tailoff;
 239	unsigned long headoff;
 240	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
 241
 242	if (rqstp->rq_prot == IPPROTO_UDP) {
 243		struct msghdr msg = {
 244			.msg_name	= &rqstp->rq_addr,
 245			.msg_namelen	= rqstp->rq_addrlen,
 246			.msg_control	= cmh,
 247			.msg_controllen	= sizeof(buffer),
 248			.msg_flags	= MSG_MORE,
 249		};
 250
 251		svc_set_cmsg_data(rqstp, cmh);
 252
 253		if (sock_sendmsg(sock, &msg, 0) < 0)
 254			goto out;
 255	}
 256
 257	tailoff = ((unsigned long)xdr->tail[0].iov_base) & (PAGE_SIZE-1);
 258	headoff = 0;
 259	len = svc_send_common(sock, xdr, rqstp->rq_respages[0], headoff,
 260			       rqstp->rq_respages[0], tailoff);
 261
 262out:
 263	dprintk("svc: socket %p sendto([%p %Zu... ], %d) = %d (addr %s)\n",
 264		svsk, xdr->head[0].iov_base, xdr->head[0].iov_len,
 265		xdr->len, len, svc_print_addr(rqstp, buf, sizeof(buf)));
 266
 267	return len;
 268}
 269
 270/*
 271 * Report socket names for nfsdfs
 272 */
 273static int svc_one_sock_name(struct svc_sock *svsk, char *buf, int remaining)
 274{
 275	const struct sock *sk = svsk->sk_sk;
 276	const char *proto_name = sk->sk_protocol == IPPROTO_UDP ?
 277							"udp" : "tcp";
 278	int len;
 279
 280	switch (sk->sk_family) {
 281	case PF_INET:
 282		len = snprintf(buf, remaining, "ipv4 %s %pI4 %d\n",
 283				proto_name,
 284				&inet_sk(sk)->inet_rcv_saddr,
 285				inet_sk(sk)->inet_num);
 286		break;
 287	case PF_INET6:
 288		len = snprintf(buf, remaining, "ipv6 %s %pI6 %d\n",
 289				proto_name,
 290				&inet6_sk(sk)->rcv_saddr,
 291				inet_sk(sk)->inet_num);
 292		break;
 293	default:
 294		len = snprintf(buf, remaining, "*unknown-%d*\n",
 295				sk->sk_family);
 296	}
 297
 298	if (len >= remaining) {
 299		*buf = '\0';
 300		return -ENAMETOOLONG;
 301	}
 302	return len;
 303}
 304
 305/**
 306 * svc_sock_names - construct a list of listener names in a string
 307 * @serv: pointer to RPC service
 308 * @buf: pointer to a buffer to fill in with socket names
 309 * @buflen: size of the buffer to be filled
 310 * @toclose: pointer to '\0'-terminated C string containing the name
 311 *		of a listener to be closed
 312 *
 313 * Fills in @buf with a '\n'-separated list of names of listener
 314 * sockets.  If @toclose is not NULL, the socket named by @toclose
 315 * is closed, and is not included in the output list.
 316 *
 317 * Returns positive length of the socket name string, or a negative
 318 * errno value on error.
 319 */
 320int svc_sock_names(struct svc_serv *serv, char *buf, const size_t buflen,
 321		   const char *toclose)
 322{
 323	struct svc_sock *svsk, *closesk = NULL;
 324	int len = 0;
 325
 326	if (!serv)
 327		return 0;
 328
 329	spin_lock_bh(&serv->sv_lock);
 330	list_for_each_entry(svsk, &serv->sv_permsocks, sk_xprt.xpt_list) {
 331		int onelen = svc_one_sock_name(svsk, buf + len, buflen - len);
 332		if (onelen < 0) {
 333			len = onelen;
 334			break;
 335		}
 336		if (toclose && strcmp(toclose, buf + len) == 0) {
 337			closesk = svsk;
 338			svc_xprt_get(&closesk->sk_xprt);
 339		} else
 340			len += onelen;
 341	}
 342	spin_unlock_bh(&serv->sv_lock);
 343
 344	if (closesk) {
 345		/* Should unregister with portmap, but you cannot
 346		 * unregister just one protocol...
 347		 */
 348		svc_close_xprt(&closesk->sk_xprt);
 349		svc_xprt_put(&closesk->sk_xprt);
 350	} else if (toclose)
 351		return -ENOENT;
 352	return len;
 353}
 354EXPORT_SYMBOL_GPL(svc_sock_names);
 355
 356/*
 357 * Check input queue length
 358 */
 359static int svc_recv_available(struct svc_sock *svsk)
 360{
 361	struct socket	*sock = svsk->sk_sock;
 362	int		avail, err;
 363
 364	err = kernel_sock_ioctl(sock, TIOCINQ, (unsigned long) &avail);
 365
 366	return (err >= 0)? avail : err;
 367}
 368
 369/*
 370 * Generic recvfrom routine.
 371 */
 372static int svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr,
 373			int buflen)
 374{
 375	struct svc_sock *svsk =
 376		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 377	struct msghdr msg = {
 378		.msg_flags	= MSG_DONTWAIT,
 379	};
 380	int len;
 381
 382	rqstp->rq_xprt_hlen = 0;
 383
 384	len = kernel_recvmsg(svsk->sk_sock, &msg, iov, nr, buflen,
 385				msg.msg_flags);
 386
 387	dprintk("svc: socket %p recvfrom(%p, %Zu) = %d\n",
 388		svsk, iov[0].iov_base, iov[0].iov_len, len);
 389	return len;
 390}
 391
 392static int svc_partial_recvfrom(struct svc_rqst *rqstp,
 393				struct kvec *iov, int nr,
 394				int buflen, unsigned int base)
 395{
 396	size_t save_iovlen;
 397	void __user *save_iovbase;
 398	unsigned int i;
 399	int ret;
 400
 401	if (base == 0)
 402		return svc_recvfrom(rqstp, iov, nr, buflen);
 403
 404	for (i = 0; i < nr; i++) {
 405		if (iov[i].iov_len > base)
 406			break;
 407		base -= iov[i].iov_len;
 408	}
 409	save_iovlen = iov[i].iov_len;
 410	save_iovbase = iov[i].iov_base;
 411	iov[i].iov_len -= base;
 412	iov[i].iov_base += base;
 413	ret = svc_recvfrom(rqstp, &iov[i], nr - i, buflen);
 414	iov[i].iov_len = save_iovlen;
 415	iov[i].iov_base = save_iovbase;
 416	return ret;
 417}
 418
 419/*
 420 * Set socket snd and rcv buffer lengths
 421 */
 422static void svc_sock_setbufsize(struct socket *sock, unsigned int snd,
 423				unsigned int rcv)
 424{
 425#if 0
 426	mm_segment_t	oldfs;
 427	oldfs = get_fs(); set_fs(KERNEL_DS);
 428	sock_setsockopt(sock, SOL_SOCKET, SO_SNDBUF,
 429			(char*)&snd, sizeof(snd));
 430	sock_setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 431			(char*)&rcv, sizeof(rcv));
 432#else
 433	/* sock_setsockopt limits use to sysctl_?mem_max,
 434	 * which isn't acceptable.  Until that is made conditional
 435	 * on not having CAP_SYS_RESOURCE or similar, we go direct...
 436	 * DaveM said I could!
 437	 */
 438	lock_sock(sock->sk);
 439	sock->sk->sk_sndbuf = snd * 2;
 440	sock->sk->sk_rcvbuf = rcv * 2;
 441	sock->sk->sk_write_space(sock->sk);
 442	release_sock(sock->sk);
 443#endif
 444}
 445/*
 446 * INET callback when data has been received on the socket.
 447 */
 448static void svc_udp_data_ready(struct sock *sk, int count)
 449{
 450	struct svc_sock	*svsk = (struct svc_sock *)sk->sk_user_data;
 451	wait_queue_head_t *wq = sk_sleep(sk);
 452
 453	if (svsk) {
 454		dprintk("svc: socket %p(inet %p), count=%d, busy=%d\n",
 455			svsk, sk, count,
 456			test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags));
 457		set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 458		svc_xprt_enqueue(&svsk->sk_xprt);
 459	}
 460	if (wq && waitqueue_active(wq))
 461		wake_up_interruptible(wq);
 462}
 463
 464/*
 465 * INET callback when space is newly available on the socket.
 466 */
 467static void svc_write_space(struct sock *sk)
 468{
 469	struct svc_sock	*svsk = (struct svc_sock *)(sk->sk_user_data);
 470	wait_queue_head_t *wq = sk_sleep(sk);
 471
 472	if (svsk) {
 473		dprintk("svc: socket %p(inet %p), write_space busy=%d\n",
 474			svsk, sk, test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags));
 475		svc_xprt_enqueue(&svsk->sk_xprt);
 476	}
 477
 478	if (wq && waitqueue_active(wq)) {
 479		dprintk("RPC svc_write_space: someone sleeping on %p\n",
 480		       svsk);
 481		wake_up_interruptible(wq);
 482	}
 483}
 484
 485static void svc_tcp_write_space(struct sock *sk)
 486{
 487	struct socket *sock = sk->sk_socket;
 488
 489	if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) && sock)
 490		clear_bit(SOCK_NOSPACE, &sock->flags);
 491	svc_write_space(sk);
 492}
 493
 494/*
 495 * See net/ipv6/ip_sockglue.c : ip_cmsg_recv_pktinfo
 496 */
 497static int svc_udp_get_dest_address4(struct svc_rqst *rqstp,
 498				     struct cmsghdr *cmh)
 499{
 500	struct in_pktinfo *pki = CMSG_DATA(cmh);
 
 
 501	if (cmh->cmsg_type != IP_PKTINFO)
 502		return 0;
 503	rqstp->rq_daddr.addr.s_addr = pki->ipi_spec_dst.s_addr;
 
 
 504	return 1;
 505}
 506
 507/*
 508 * See net/ipv6/datagram.c : datagram_recv_ctl
 509 */
 510static int svc_udp_get_dest_address6(struct svc_rqst *rqstp,
 511				     struct cmsghdr *cmh)
 512{
 513	struct in6_pktinfo *pki = CMSG_DATA(cmh);
 
 
 514	if (cmh->cmsg_type != IPV6_PKTINFO)
 515		return 0;
 516	ipv6_addr_copy(&rqstp->rq_daddr.addr6, &pki->ipi6_addr);
 
 
 
 517	return 1;
 518}
 519
 520/*
 521 * Copy the UDP datagram's destination address to the rqstp structure.
 522 * The 'destination' address in this case is the address to which the
 523 * peer sent the datagram, i.e. our local address. For multihomed
 524 * hosts, this can change from msg to msg. Note that only the IP
 525 * address changes, the port number should remain the same.
 526 */
 527static int svc_udp_get_dest_address(struct svc_rqst *rqstp,
 528				    struct cmsghdr *cmh)
 529{
 530	switch (cmh->cmsg_level) {
 531	case SOL_IP:
 532		return svc_udp_get_dest_address4(rqstp, cmh);
 533	case SOL_IPV6:
 534		return svc_udp_get_dest_address6(rqstp, cmh);
 535	}
 536
 537	return 0;
 538}
 539
 540/*
 541 * Receive a datagram from a UDP socket.
 542 */
 543static int svc_udp_recvfrom(struct svc_rqst *rqstp)
 544{
 545	struct svc_sock	*svsk =
 546		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 547	struct svc_serv	*serv = svsk->sk_xprt.xpt_server;
 548	struct sk_buff	*skb;
 549	union {
 550		struct cmsghdr	hdr;
 551		long		all[SVC_PKTINFO_SPACE / sizeof(long)];
 552	} buffer;
 553	struct cmsghdr *cmh = &buffer.hdr;
 554	struct msghdr msg = {
 555		.msg_name = svc_addr(rqstp),
 556		.msg_control = cmh,
 557		.msg_controllen = sizeof(buffer),
 558		.msg_flags = MSG_DONTWAIT,
 559	};
 560	size_t len;
 561	int err;
 562
 563	if (test_and_clear_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags))
 564	    /* udp sockets need large rcvbuf as all pending
 565	     * requests are still in that buffer.  sndbuf must
 566	     * also be large enough that there is enough space
 567	     * for one reply per thread.  We count all threads
 568	     * rather than threads in a particular pool, which
 569	     * provides an upper bound on the number of threads
 570	     * which will access the socket.
 571	     */
 572	    svc_sock_setbufsize(svsk->sk_sock,
 573				(serv->sv_nrthreads+3) * serv->sv_max_mesg,
 574				(serv->sv_nrthreads+3) * serv->sv_max_mesg);
 575
 576	clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 577	skb = NULL;
 578	err = kernel_recvmsg(svsk->sk_sock, &msg, NULL,
 579			     0, 0, MSG_PEEK | MSG_DONTWAIT);
 580	if (err >= 0)
 581		skb = skb_recv_datagram(svsk->sk_sk, 0, 1, &err);
 582
 583	if (skb == NULL) {
 584		if (err != -EAGAIN) {
 585			/* possibly an icmp error */
 586			dprintk("svc: recvfrom returned error %d\n", -err);
 587			set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 588		}
 589		return -EAGAIN;
 590	}
 591	len = svc_addr_len(svc_addr(rqstp));
 592	if (len == 0)
 593		return -EAFNOSUPPORT;
 594	rqstp->rq_addrlen = len;
 595	if (skb->tstamp.tv64 == 0) {
 596		skb->tstamp = ktime_get_real();
 597		/* Don't enable netstamp, sunrpc doesn't
 598		   need that much accuracy */
 599	}
 600	svsk->sk_sk->sk_stamp = skb->tstamp;
 601	set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); /* there may be more data... */
 602
 603	len  = skb->len - sizeof(struct udphdr);
 604	rqstp->rq_arg.len = len;
 605
 606	rqstp->rq_prot = IPPROTO_UDP;
 607
 608	if (!svc_udp_get_dest_address(rqstp, cmh)) {
 609		if (net_ratelimit())
 610			printk(KERN_WARNING
 611				"svc: received unknown control message %d/%d; "
 612				"dropping RPC reply datagram\n",
 613					cmh->cmsg_level, cmh->cmsg_type);
 614		skb_free_datagram_locked(svsk->sk_sk, skb);
 615		return 0;
 616	}
 
 617
 618	if (skb_is_nonlinear(skb)) {
 619		/* we have to copy */
 620		local_bh_disable();
 621		if (csum_partial_copy_to_xdr(&rqstp->rq_arg, skb)) {
 622			local_bh_enable();
 623			/* checksum error */
 624			skb_free_datagram_locked(svsk->sk_sk, skb);
 625			return 0;
 626		}
 627		local_bh_enable();
 628		skb_free_datagram_locked(svsk->sk_sk, skb);
 629	} else {
 630		/* we can use it in-place */
 631		rqstp->rq_arg.head[0].iov_base = skb->data +
 632			sizeof(struct udphdr);
 633		rqstp->rq_arg.head[0].iov_len = len;
 634		if (skb_checksum_complete(skb)) {
 635			skb_free_datagram_locked(svsk->sk_sk, skb);
 636			return 0;
 637		}
 638		rqstp->rq_xprt_ctxt = skb;
 639	}
 640
 641	rqstp->rq_arg.page_base = 0;
 642	if (len <= rqstp->rq_arg.head[0].iov_len) {
 643		rqstp->rq_arg.head[0].iov_len = len;
 644		rqstp->rq_arg.page_len = 0;
 645		rqstp->rq_respages = rqstp->rq_pages+1;
 646	} else {
 647		rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len;
 648		rqstp->rq_respages = rqstp->rq_pages + 1 +
 649			DIV_ROUND_UP(rqstp->rq_arg.page_len, PAGE_SIZE);
 650	}
 651
 652	if (serv->sv_stats)
 653		serv->sv_stats->netudpcnt++;
 654
 655	return len;
 656}
 657
 658static int
 659svc_udp_sendto(struct svc_rqst *rqstp)
 660{
 661	int		error;
 662
 663	error = svc_sendto(rqstp, &rqstp->rq_res);
 664	if (error == -ECONNREFUSED)
 665		/* ICMP error on earlier request. */
 666		error = svc_sendto(rqstp, &rqstp->rq_res);
 667
 668	return error;
 669}
 670
 671static void svc_udp_prep_reply_hdr(struct svc_rqst *rqstp)
 672{
 673}
 674
 675static int svc_udp_has_wspace(struct svc_xprt *xprt)
 676{
 677	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
 678	struct svc_serv	*serv = xprt->xpt_server;
 679	unsigned long required;
 680
 681	/*
 682	 * Set the SOCK_NOSPACE flag before checking the available
 683	 * sock space.
 684	 */
 685	set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
 686	required = atomic_read(&svsk->sk_xprt.xpt_reserved) + serv->sv_max_mesg;
 687	if (required*2 > sock_wspace(svsk->sk_sk))
 688		return 0;
 689	clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
 690	return 1;
 691}
 692
 693static struct svc_xprt *svc_udp_accept(struct svc_xprt *xprt)
 694{
 695	BUG();
 696	return NULL;
 697}
 698
 699static struct svc_xprt *svc_udp_create(struct svc_serv *serv,
 700				       struct net *net,
 701				       struct sockaddr *sa, int salen,
 702				       int flags)
 703{
 704	return svc_create_socket(serv, IPPROTO_UDP, net, sa, salen, flags);
 705}
 706
 707static struct svc_xprt_ops svc_udp_ops = {
 708	.xpo_create = svc_udp_create,
 709	.xpo_recvfrom = svc_udp_recvfrom,
 710	.xpo_sendto = svc_udp_sendto,
 711	.xpo_release_rqst = svc_release_skb,
 712	.xpo_detach = svc_sock_detach,
 713	.xpo_free = svc_sock_free,
 714	.xpo_prep_reply_hdr = svc_udp_prep_reply_hdr,
 715	.xpo_has_wspace = svc_udp_has_wspace,
 716	.xpo_accept = svc_udp_accept,
 717};
 718
 719static struct svc_xprt_class svc_udp_class = {
 720	.xcl_name = "udp",
 721	.xcl_owner = THIS_MODULE,
 722	.xcl_ops = &svc_udp_ops,
 723	.xcl_max_payload = RPCSVC_MAXPAYLOAD_UDP,
 724};
 725
 726static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv)
 727{
 728	int err, level, optname, one = 1;
 729
 730	svc_xprt_init(&svc_udp_class, &svsk->sk_xprt, serv);
 
 731	clear_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
 732	svsk->sk_sk->sk_data_ready = svc_udp_data_ready;
 733	svsk->sk_sk->sk_write_space = svc_write_space;
 734
 735	/* initialise setting must have enough space to
 736	 * receive and respond to one request.
 737	 * svc_udp_recvfrom will re-adjust if necessary
 738	 */
 739	svc_sock_setbufsize(svsk->sk_sock,
 740			    3 * svsk->sk_xprt.xpt_server->sv_max_mesg,
 741			    3 * svsk->sk_xprt.xpt_server->sv_max_mesg);
 742
 743	/* data might have come in before data_ready set up */
 744	set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 745	set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
 746
 747	/* make sure we get destination address info */
 748	switch (svsk->sk_sk->sk_family) {
 749	case AF_INET:
 750		level = SOL_IP;
 751		optname = IP_PKTINFO;
 752		break;
 753	case AF_INET6:
 754		level = SOL_IPV6;
 755		optname = IPV6_RECVPKTINFO;
 756		break;
 757	default:
 758		BUG();
 759	}
 760	err = kernel_setsockopt(svsk->sk_sock, level, optname,
 761					(char *)&one, sizeof(one));
 762	dprintk("svc: kernel_setsockopt returned %d\n", err);
 763}
 764
 765/*
 766 * A data_ready event on a listening socket means there's a connection
 767 * pending. Do not use state_change as a substitute for it.
 768 */
 769static void svc_tcp_listen_data_ready(struct sock *sk, int count_unused)
 770{
 771	struct svc_sock	*svsk = (struct svc_sock *)sk->sk_user_data;
 772	wait_queue_head_t *wq;
 773
 774	dprintk("svc: socket %p TCP (listen) state change %d\n",
 775		sk, sk->sk_state);
 776
 777	/*
 778	 * This callback may called twice when a new connection
 779	 * is established as a child socket inherits everything
 780	 * from a parent LISTEN socket.
 781	 * 1) data_ready method of the parent socket will be called
 782	 *    when one of child sockets become ESTABLISHED.
 783	 * 2) data_ready method of the child socket may be called
 784	 *    when it receives data before the socket is accepted.
 785	 * In case of 2, we should ignore it silently.
 786	 */
 787	if (sk->sk_state == TCP_LISTEN) {
 788		if (svsk) {
 789			set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
 790			svc_xprt_enqueue(&svsk->sk_xprt);
 791		} else
 792			printk("svc: socket %p: no user data\n", sk);
 793	}
 794
 795	wq = sk_sleep(sk);
 796	if (wq && waitqueue_active(wq))
 797		wake_up_interruptible_all(wq);
 798}
 799
 800/*
 801 * A state change on a connected socket means it's dying or dead.
 802 */
 803static void svc_tcp_state_change(struct sock *sk)
 804{
 805	struct svc_sock	*svsk = (struct svc_sock *)sk->sk_user_data;
 806	wait_queue_head_t *wq = sk_sleep(sk);
 807
 808	dprintk("svc: socket %p TCP (connected) state change %d (svsk %p)\n",
 809		sk, sk->sk_state, sk->sk_user_data);
 810
 811	if (!svsk)
 812		printk("svc: socket %p: no user data\n", sk);
 813	else {
 814		set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
 815		svc_xprt_enqueue(&svsk->sk_xprt);
 816	}
 817	if (wq && waitqueue_active(wq))
 818		wake_up_interruptible_all(wq);
 819}
 820
 821static void svc_tcp_data_ready(struct sock *sk, int count)
 822{
 823	struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
 824	wait_queue_head_t *wq = sk_sleep(sk);
 825
 826	dprintk("svc: socket %p TCP data ready (svsk %p)\n",
 827		sk, sk->sk_user_data);
 828	if (svsk) {
 829		set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 830		svc_xprt_enqueue(&svsk->sk_xprt);
 831	}
 832	if (wq && waitqueue_active(wq))
 833		wake_up_interruptible(wq);
 834}
 835
 836/*
 837 * Accept a TCP connection
 838 */
 839static struct svc_xprt *svc_tcp_accept(struct svc_xprt *xprt)
 840{
 841	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
 842	struct sockaddr_storage addr;
 843	struct sockaddr	*sin = (struct sockaddr *) &addr;
 844	struct svc_serv	*serv = svsk->sk_xprt.xpt_server;
 845	struct socket	*sock = svsk->sk_sock;
 846	struct socket	*newsock;
 847	struct svc_sock	*newsvsk;
 848	int		err, slen;
 849	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
 850
 851	dprintk("svc: tcp_accept %p sock %p\n", svsk, sock);
 852	if (!sock)
 853		return NULL;
 854
 855	clear_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
 856	err = kernel_accept(sock, &newsock, O_NONBLOCK);
 857	if (err < 0) {
 858		if (err == -ENOMEM)
 859			printk(KERN_WARNING "%s: no more sockets!\n",
 860			       serv->sv_name);
 861		else if (err != -EAGAIN && net_ratelimit())
 862			printk(KERN_WARNING "%s: accept failed (err %d)!\n",
 863				   serv->sv_name, -err);
 864		return NULL;
 865	}
 866	set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
 867
 868	err = kernel_getpeername(newsock, sin, &slen);
 869	if (err < 0) {
 870		if (net_ratelimit())
 871			printk(KERN_WARNING "%s: peername failed (err %d)!\n",
 872				   serv->sv_name, -err);
 873		goto failed;		/* aborted connection or whatever */
 874	}
 875
 876	/* Ideally, we would want to reject connections from unauthorized
 877	 * hosts here, but when we get encryption, the IP of the host won't
 878	 * tell us anything.  For now just warn about unpriv connections.
 879	 */
 880	if (!svc_port_is_privileged(sin)) {
 881		dprintk(KERN_WARNING
 882			"%s: connect from unprivileged port: %s\n",
 883			serv->sv_name,
 884			__svc_print_addr(sin, buf, sizeof(buf)));
 885	}
 886	dprintk("%s: connect from %s\n", serv->sv_name,
 887		__svc_print_addr(sin, buf, sizeof(buf)));
 888
 889	/* make sure that a write doesn't block forever when
 890	 * low on memory
 891	 */
 892	newsock->sk->sk_sndtimeo = HZ*30;
 893
 894	if (!(newsvsk = svc_setup_socket(serv, newsock, &err,
 895				 (SVC_SOCK_ANONYMOUS | SVC_SOCK_TEMPORARY))))
 896		goto failed;
 897	svc_xprt_set_remote(&newsvsk->sk_xprt, sin, slen);
 898	err = kernel_getsockname(newsock, sin, &slen);
 899	if (unlikely(err < 0)) {
 900		dprintk("svc_tcp_accept: kernel_getsockname error %d\n", -err);
 901		slen = offsetof(struct sockaddr, sa_data);
 902	}
 903	svc_xprt_set_local(&newsvsk->sk_xprt, sin, slen);
 904
 905	if (serv->sv_stats)
 906		serv->sv_stats->nettcpconn++;
 907
 908	return &newsvsk->sk_xprt;
 909
 910failed:
 911	sock_release(newsock);
 912	return NULL;
 913}
 914
 915static unsigned int svc_tcp_restore_pages(struct svc_sock *svsk, struct svc_rqst *rqstp)
 916{
 917	unsigned int i, len, npages;
 918
 919	if (svsk->sk_tcplen <= sizeof(rpc_fraghdr))
 920		return 0;
 921	len = svsk->sk_tcplen - sizeof(rpc_fraghdr);
 922	npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
 923	for (i = 0; i < npages; i++) {
 924		if (rqstp->rq_pages[i] != NULL)
 925			put_page(rqstp->rq_pages[i]);
 926		BUG_ON(svsk->sk_pages[i] == NULL);
 927		rqstp->rq_pages[i] = svsk->sk_pages[i];
 928		svsk->sk_pages[i] = NULL;
 929	}
 930	rqstp->rq_arg.head[0].iov_base = page_address(rqstp->rq_pages[0]);
 931	return len;
 932}
 933
 934static void svc_tcp_save_pages(struct svc_sock *svsk, struct svc_rqst *rqstp)
 935{
 936	unsigned int i, len, npages;
 937
 938	if (svsk->sk_tcplen <= sizeof(rpc_fraghdr))
 939		return;
 940	len = svsk->sk_tcplen - sizeof(rpc_fraghdr);
 941	npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
 942	for (i = 0; i < npages; i++) {
 943		svsk->sk_pages[i] = rqstp->rq_pages[i];
 944		rqstp->rq_pages[i] = NULL;
 945	}
 946}
 947
 948static void svc_tcp_clear_pages(struct svc_sock *svsk)
 949{
 950	unsigned int i, len, npages;
 951
 952	if (svsk->sk_tcplen <= sizeof(rpc_fraghdr))
 953		goto out;
 954	len = svsk->sk_tcplen - sizeof(rpc_fraghdr);
 955	npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
 956	for (i = 0; i < npages; i++) {
 957		BUG_ON(svsk->sk_pages[i] == NULL);
 958		put_page(svsk->sk_pages[i]);
 959		svsk->sk_pages[i] = NULL;
 960	}
 961out:
 962	svsk->sk_tcplen = 0;
 963}
 964
 965/*
 966 * Receive data.
 967 * If we haven't gotten the record length yet, get the next four bytes.
 968 * Otherwise try to gobble up as much as possible up to the complete
 969 * record length.
 970 */
 971static int svc_tcp_recv_record(struct svc_sock *svsk, struct svc_rqst *rqstp)
 972{
 973	struct svc_serv	*serv = svsk->sk_xprt.xpt_server;
 974	unsigned int want;
 975	int len;
 976
 977	clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 978
 979	if (svsk->sk_tcplen < sizeof(rpc_fraghdr)) {
 980		struct kvec	iov;
 981
 982		want = sizeof(rpc_fraghdr) - svsk->sk_tcplen;
 983		iov.iov_base = ((char *) &svsk->sk_reclen) + svsk->sk_tcplen;
 984		iov.iov_len  = want;
 985		if ((len = svc_recvfrom(rqstp, &iov, 1, want)) < 0)
 986			goto error;
 987		svsk->sk_tcplen += len;
 988
 989		if (len < want) {
 990			dprintk("svc: short recvfrom while reading record "
 991				"length (%d of %d)\n", len, want);
 992			return -EAGAIN;
 993		}
 994
 995		svsk->sk_reclen = ntohl(svsk->sk_reclen);
 996		if (!(svsk->sk_reclen & RPC_LAST_STREAM_FRAGMENT)) {
 997			/* FIXME: technically, a record can be fragmented,
 998			 *  and non-terminal fragments will not have the top
 999			 *  bit set in the fragment length header.
1000			 *  But apparently no known nfs clients send fragmented
1001			 *  records. */
1002			if (net_ratelimit())
1003				printk(KERN_NOTICE "RPC: multiple fragments "
1004					"per record not supported\n");
1005			goto err_delete;
1006		}
1007
1008		svsk->sk_reclen &= RPC_FRAGMENT_SIZE_MASK;
1009		dprintk("svc: TCP record, %d bytes\n", svsk->sk_reclen);
1010		if (svsk->sk_reclen > serv->sv_max_mesg) {
1011			if (net_ratelimit())
1012				printk(KERN_NOTICE "RPC: "
1013					"fragment too large: 0x%08lx\n",
1014					(unsigned long)svsk->sk_reclen);
1015			goto err_delete;
1016		}
1017	}
1018
1019	if (svsk->sk_reclen < 8)
1020		goto err_delete; /* client is nuts. */
1021
1022	len = svsk->sk_reclen;
1023
1024	return len;
1025error:
1026	dprintk("RPC: TCP recv_record got %d\n", len);
1027	return len;
1028err_delete:
1029	set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1030	return -EAGAIN;
1031}
1032
1033static int receive_cb_reply(struct svc_sock *svsk, struct svc_rqst *rqstp)
1034{
1035	struct rpc_xprt *bc_xprt = svsk->sk_xprt.xpt_bc_xprt;
1036	struct rpc_rqst *req = NULL;
1037	struct kvec *src, *dst;
1038	__be32 *p = (__be32 *)rqstp->rq_arg.head[0].iov_base;
1039	__be32 xid;
1040	__be32 calldir;
1041
1042	xid = *p++;
1043	calldir = *p;
1044
1045	if (bc_xprt)
1046		req = xprt_lookup_rqst(bc_xprt, xid);
1047
1048	if (!req) {
1049		printk(KERN_NOTICE
1050			"%s: Got unrecognized reply: "
1051			"calldir 0x%x xpt_bc_xprt %p xid %08x\n",
1052			__func__, ntohl(calldir),
1053			bc_xprt, xid);
1054		return -EAGAIN;
1055	}
1056
1057	memcpy(&req->rq_private_buf, &req->rq_rcv_buf, sizeof(struct xdr_buf));
1058	/*
1059	 * XXX!: cheating for now!  Only copying HEAD.
1060	 * But we know this is good enough for now (in fact, for any
1061	 * callback reply in the forseeable future).
1062	 */
1063	dst = &req->rq_private_buf.head[0];
1064	src = &rqstp->rq_arg.head[0];
1065	if (dst->iov_len < src->iov_len)
1066		return -EAGAIN; /* whatever; just giving up. */
1067	memcpy(dst->iov_base, src->iov_base, src->iov_len);
1068	xprt_complete_rqst(req->rq_task, svsk->sk_reclen);
1069	rqstp->rq_arg.len = 0;
1070	return 0;
1071}
1072
1073static int copy_pages_to_kvecs(struct kvec *vec, struct page **pages, int len)
1074{
1075	int i = 0;
1076	int t = 0;
1077
1078	while (t < len) {
1079		vec[i].iov_base = page_address(pages[i]);
1080		vec[i].iov_len = PAGE_SIZE;
1081		i++;
1082		t += PAGE_SIZE;
1083	}
1084	return i;
1085}
1086
1087
1088/*
1089 * Receive data from a TCP socket.
1090 */
1091static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
1092{
1093	struct svc_sock	*svsk =
1094		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
1095	struct svc_serv	*serv = svsk->sk_xprt.xpt_server;
1096	int		len;
1097	struct kvec *vec;
1098	unsigned int want, base;
1099	__be32 *p;
1100	__be32 calldir;
1101	int pnum;
1102
1103	dprintk("svc: tcp_recv %p data %d conn %d close %d\n",
1104		svsk, test_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags),
1105		test_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags),
1106		test_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags));
1107
1108	len = svc_tcp_recv_record(svsk, rqstp);
1109	if (len < 0)
1110		goto error;
1111
1112	base = svc_tcp_restore_pages(svsk, rqstp);
1113	want = svsk->sk_reclen - base;
1114
1115	vec = rqstp->rq_vec;
1116
1117	pnum = copy_pages_to_kvecs(&vec[0], &rqstp->rq_pages[0],
1118						svsk->sk_reclen);
1119
1120	rqstp->rq_respages = &rqstp->rq_pages[pnum];
1121
1122	/* Now receive data */
1123	len = svc_partial_recvfrom(rqstp, vec, pnum, want, base);
1124	if (len >= 0)
1125		svsk->sk_tcplen += len;
1126	if (len != want) {
 
1127		if (len < 0 && len != -EAGAIN)
1128			goto err_other;
1129		svc_tcp_save_pages(svsk, rqstp);
1130		dprintk("svc: incomplete TCP record (%d of %d)\n",
1131			svsk->sk_tcplen, svsk->sk_reclen);
1132		goto err_noclose;
1133	}
1134
1135	rqstp->rq_arg.len = svsk->sk_reclen;
1136	rqstp->rq_arg.page_base = 0;
1137	if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len) {
1138		rqstp->rq_arg.head[0].iov_len = rqstp->rq_arg.len;
1139		rqstp->rq_arg.page_len = 0;
1140	} else
1141		rqstp->rq_arg.page_len = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len;
1142
1143	rqstp->rq_xprt_ctxt   = NULL;
1144	rqstp->rq_prot	      = IPPROTO_TCP;
1145
1146	p = (__be32 *)rqstp->rq_arg.head[0].iov_base;
1147	calldir = p[1];
1148	if (calldir)
1149		len = receive_cb_reply(svsk, rqstp);
1150
1151	/* Reset TCP read info */
1152	svsk->sk_reclen = 0;
1153	svsk->sk_tcplen = 0;
1154	/* If we have more data, signal svc_xprt_enqueue() to try again */
1155	if (svc_recv_available(svsk) > sizeof(rpc_fraghdr))
1156		set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
1157
1158	if (len < 0)
1159		goto error;
1160
1161	svc_xprt_copy_addrs(rqstp, &svsk->sk_xprt);
1162	if (serv->sv_stats)
1163		serv->sv_stats->nettcpcnt++;
1164
1165	dprintk("svc: TCP complete record (%d bytes)\n", rqstp->rq_arg.len);
1166	return rqstp->rq_arg.len;
1167
1168error:
1169	if (len != -EAGAIN)
1170		goto err_other;
1171	dprintk("RPC: TCP recvfrom got EAGAIN\n");
1172	return -EAGAIN;
1173err_other:
1174	printk(KERN_NOTICE "%s: recvfrom returned errno %d\n",
1175	       svsk->sk_xprt.xpt_server->sv_name, -len);
1176	set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1177err_noclose:
1178	return -EAGAIN;	/* record not complete */
1179}
1180
1181/*
1182 * Send out data on TCP socket.
1183 */
1184static int svc_tcp_sendto(struct svc_rqst *rqstp)
1185{
1186	struct xdr_buf	*xbufp = &rqstp->rq_res;
1187	int sent;
1188	__be32 reclen;
1189
1190	/* Set up the first element of the reply kvec.
1191	 * Any other kvecs that may be in use have been taken
1192	 * care of by the server implementation itself.
1193	 */
1194	reclen = htonl(0x80000000|((xbufp->len ) - 4));
1195	memcpy(xbufp->head[0].iov_base, &reclen, 4);
1196
1197	sent = svc_sendto(rqstp, &rqstp->rq_res);
1198	if (sent != xbufp->len) {
1199		printk(KERN_NOTICE
1200		       "rpc-srv/tcp: %s: %s %d when sending %d bytes "
1201		       "- shutting down socket\n",
1202		       rqstp->rq_xprt->xpt_server->sv_name,
1203		       (sent<0)?"got error":"sent only",
1204		       sent, xbufp->len);
1205		set_bit(XPT_CLOSE, &rqstp->rq_xprt->xpt_flags);
1206		svc_xprt_enqueue(rqstp->rq_xprt);
1207		sent = -EAGAIN;
1208	}
1209	return sent;
1210}
1211
1212/*
1213 * Setup response header. TCP has a 4B record length field.
1214 */
1215static void svc_tcp_prep_reply_hdr(struct svc_rqst *rqstp)
1216{
1217	struct kvec *resv = &rqstp->rq_res.head[0];
1218
1219	/* tcp needs a space for the record length... */
1220	svc_putnl(resv, 0);
1221}
1222
1223static int svc_tcp_has_wspace(struct svc_xprt *xprt)
1224{
1225	struct svc_sock *svsk =	container_of(xprt, struct svc_sock, sk_xprt);
1226	struct svc_serv *serv = svsk->sk_xprt.xpt_server;
1227	int required;
1228
1229	if (test_bit(XPT_LISTENER, &xprt->xpt_flags))
1230		return 1;
1231	required = atomic_read(&xprt->xpt_reserved) + serv->sv_max_mesg;
1232	if (sk_stream_wspace(svsk->sk_sk) >= required)
1233		return 1;
1234	set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
1235	return 0;
1236}
1237
1238static struct svc_xprt *svc_tcp_create(struct svc_serv *serv,
1239				       struct net *net,
1240				       struct sockaddr *sa, int salen,
1241				       int flags)
1242{
1243	return svc_create_socket(serv, IPPROTO_TCP, net, sa, salen, flags);
1244}
1245
1246#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1247static struct svc_xprt *svc_bc_create_socket(struct svc_serv *, int,
1248					     struct net *, struct sockaddr *,
1249					     int, int);
1250static void svc_bc_sock_free(struct svc_xprt *xprt);
1251
1252static struct svc_xprt *svc_bc_tcp_create(struct svc_serv *serv,
1253				       struct net *net,
1254				       struct sockaddr *sa, int salen,
1255				       int flags)
1256{
1257	return svc_bc_create_socket(serv, IPPROTO_TCP, net, sa, salen, flags);
1258}
1259
1260static void svc_bc_tcp_sock_detach(struct svc_xprt *xprt)
1261{
1262}
1263
1264static struct svc_xprt_ops svc_tcp_bc_ops = {
1265	.xpo_create = svc_bc_tcp_create,
1266	.xpo_detach = svc_bc_tcp_sock_detach,
1267	.xpo_free = svc_bc_sock_free,
1268	.xpo_prep_reply_hdr = svc_tcp_prep_reply_hdr,
1269};
1270
1271static struct svc_xprt_class svc_tcp_bc_class = {
1272	.xcl_name = "tcp-bc",
1273	.xcl_owner = THIS_MODULE,
1274	.xcl_ops = &svc_tcp_bc_ops,
1275	.xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP,
1276};
1277
1278static void svc_init_bc_xprt_sock(void)
1279{
1280	svc_reg_xprt_class(&svc_tcp_bc_class);
1281}
1282
1283static void svc_cleanup_bc_xprt_sock(void)
1284{
1285	svc_unreg_xprt_class(&svc_tcp_bc_class);
1286}
1287#else /* CONFIG_SUNRPC_BACKCHANNEL */
1288static void svc_init_bc_xprt_sock(void)
1289{
1290}
1291
1292static void svc_cleanup_bc_xprt_sock(void)
1293{
1294}
1295#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1296
1297static struct svc_xprt_ops svc_tcp_ops = {
1298	.xpo_create = svc_tcp_create,
1299	.xpo_recvfrom = svc_tcp_recvfrom,
1300	.xpo_sendto = svc_tcp_sendto,
1301	.xpo_release_rqst = svc_release_skb,
1302	.xpo_detach = svc_tcp_sock_detach,
1303	.xpo_free = svc_sock_free,
1304	.xpo_prep_reply_hdr = svc_tcp_prep_reply_hdr,
1305	.xpo_has_wspace = svc_tcp_has_wspace,
1306	.xpo_accept = svc_tcp_accept,
1307};
1308
1309static struct svc_xprt_class svc_tcp_class = {
1310	.xcl_name = "tcp",
1311	.xcl_owner = THIS_MODULE,
1312	.xcl_ops = &svc_tcp_ops,
1313	.xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP,
1314};
1315
1316void svc_init_xprt_sock(void)
1317{
1318	svc_reg_xprt_class(&svc_tcp_class);
1319	svc_reg_xprt_class(&svc_udp_class);
1320	svc_init_bc_xprt_sock();
1321}
1322
1323void svc_cleanup_xprt_sock(void)
1324{
1325	svc_unreg_xprt_class(&svc_tcp_class);
1326	svc_unreg_xprt_class(&svc_udp_class);
1327	svc_cleanup_bc_xprt_sock();
1328}
1329
1330static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv)
1331{
1332	struct sock	*sk = svsk->sk_sk;
1333
1334	svc_xprt_init(&svc_tcp_class, &svsk->sk_xprt, serv);
 
1335	set_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
1336	if (sk->sk_state == TCP_LISTEN) {
1337		dprintk("setting up TCP socket for listening\n");
1338		set_bit(XPT_LISTENER, &svsk->sk_xprt.xpt_flags);
1339		sk->sk_data_ready = svc_tcp_listen_data_ready;
1340		set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
1341	} else {
1342		dprintk("setting up TCP socket for reading\n");
1343		sk->sk_state_change = svc_tcp_state_change;
1344		sk->sk_data_ready = svc_tcp_data_ready;
1345		sk->sk_write_space = svc_tcp_write_space;
1346
1347		svsk->sk_reclen = 0;
1348		svsk->sk_tcplen = 0;
1349		memset(&svsk->sk_pages[0], 0, sizeof(svsk->sk_pages));
1350
1351		tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
1352
1353		set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
1354		if (sk->sk_state != TCP_ESTABLISHED)
1355			set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1356	}
1357}
1358
1359void svc_sock_update_bufs(struct svc_serv *serv)
1360{
1361	/*
1362	 * The number of server threads has changed. Update
1363	 * rcvbuf and sndbuf accordingly on all sockets
1364	 */
1365	struct svc_sock *svsk;
1366
1367	spin_lock_bh(&serv->sv_lock);
1368	list_for_each_entry(svsk, &serv->sv_permsocks, sk_xprt.xpt_list)
1369		set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
1370	list_for_each_entry(svsk, &serv->sv_tempsocks, sk_xprt.xpt_list)
1371		set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
1372	spin_unlock_bh(&serv->sv_lock);
1373}
1374EXPORT_SYMBOL_GPL(svc_sock_update_bufs);
1375
1376/*
1377 * Initialize socket for RPC use and create svc_sock struct
1378 * XXX: May want to setsockopt SO_SNDBUF and SO_RCVBUF.
1379 */
1380static struct svc_sock *svc_setup_socket(struct svc_serv *serv,
1381						struct socket *sock,
1382						int *errp, int flags)
1383{
1384	struct svc_sock	*svsk;
1385	struct sock	*inet;
1386	int		pmap_register = !(flags & SVC_SOCK_ANONYMOUS);
1387
1388	dprintk("svc: svc_setup_socket %p\n", sock);
1389	if (!(svsk = kzalloc(sizeof(*svsk), GFP_KERNEL))) {
1390		*errp = -ENOMEM;
1391		return NULL;
1392	}
1393
1394	inet = sock->sk;
1395
1396	/* Register socket with portmapper */
1397	if (*errp >= 0 && pmap_register)
1398		*errp = svc_register(serv, inet->sk_family, inet->sk_protocol,
 
1399				     ntohs(inet_sk(inet)->inet_sport));
1400
1401	if (*errp < 0) {
1402		kfree(svsk);
1403		return NULL;
1404	}
1405
1406	inet->sk_user_data = svsk;
1407	svsk->sk_sock = sock;
1408	svsk->sk_sk = inet;
1409	svsk->sk_ostate = inet->sk_state_change;
1410	svsk->sk_odata = inet->sk_data_ready;
1411	svsk->sk_owspace = inet->sk_write_space;
1412
1413	/* Initialize the socket */
1414	if (sock->type == SOCK_DGRAM)
1415		svc_udp_init(svsk, serv);
1416	else {
1417		/* initialise setting must have enough space to
1418		 * receive and respond to one request.
1419		 */
1420		svc_sock_setbufsize(svsk->sk_sock, 4 * serv->sv_max_mesg,
1421					4 * serv->sv_max_mesg);
1422		svc_tcp_init(svsk, serv);
1423	}
1424
1425	dprintk("svc: svc_setup_socket created %p (inet %p)\n",
1426				svsk, svsk->sk_sk);
1427
1428	return svsk;
1429}
1430
1431/**
1432 * svc_addsock - add a listener socket to an RPC service
1433 * @serv: pointer to RPC service to which to add a new listener
1434 * @fd: file descriptor of the new listener
1435 * @name_return: pointer to buffer to fill in with name of listener
1436 * @len: size of the buffer
1437 *
1438 * Fills in socket name and returns positive length of name if successful.
1439 * Name is terminated with '\n'.  On error, returns a negative errno
1440 * value.
1441 */
1442int svc_addsock(struct svc_serv *serv, const int fd, char *name_return,
1443		const size_t len)
1444{
1445	int err = 0;
1446	struct socket *so = sockfd_lookup(fd, &err);
1447	struct svc_sock *svsk = NULL;
1448
1449	if (!so)
1450		return err;
1451	if ((so->sk->sk_family != PF_INET) && (so->sk->sk_family != PF_INET6))
1452		err =  -EAFNOSUPPORT;
1453	else if (so->sk->sk_protocol != IPPROTO_TCP &&
1454	    so->sk->sk_protocol != IPPROTO_UDP)
1455		err =  -EPROTONOSUPPORT;
1456	else if (so->state > SS_UNCONNECTED)
1457		err = -EISCONN;
1458	else {
1459		if (!try_module_get(THIS_MODULE))
1460			err = -ENOENT;
1461		else
1462			svsk = svc_setup_socket(serv, so, &err,
1463						SVC_SOCK_DEFAULTS);
1464		if (svsk) {
1465			struct sockaddr_storage addr;
1466			struct sockaddr *sin = (struct sockaddr *)&addr;
1467			int salen;
1468			if (kernel_getsockname(svsk->sk_sock, sin, &salen) == 0)
1469				svc_xprt_set_local(&svsk->sk_xprt, sin, salen);
1470			clear_bit(XPT_TEMP, &svsk->sk_xprt.xpt_flags);
1471			spin_lock_bh(&serv->sv_lock);
1472			list_add(&svsk->sk_xprt.xpt_list, &serv->sv_permsocks);
1473			spin_unlock_bh(&serv->sv_lock);
1474			svc_xprt_received(&svsk->sk_xprt);
1475			err = 0;
1476		} else
1477			module_put(THIS_MODULE);
1478	}
1479	if (err) {
1480		sockfd_put(so);
1481		return err;
1482	}
1483	return svc_one_sock_name(svsk, name_return, len);
1484}
1485EXPORT_SYMBOL_GPL(svc_addsock);
1486
1487/*
1488 * Create socket for RPC service.
1489 */
1490static struct svc_xprt *svc_create_socket(struct svc_serv *serv,
1491					  int protocol,
1492					  struct net *net,
1493					  struct sockaddr *sin, int len,
1494					  int flags)
1495{
1496	struct svc_sock	*svsk;
1497	struct socket	*sock;
1498	int		error;
1499	int		type;
1500	struct sockaddr_storage addr;
1501	struct sockaddr *newsin = (struct sockaddr *)&addr;
1502	int		newlen;
1503	int		family;
1504	int		val;
1505	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
1506
1507	dprintk("svc: svc_create_socket(%s, %d, %s)\n",
1508			serv->sv_program->pg_name, protocol,
1509			__svc_print_addr(sin, buf, sizeof(buf)));
1510
1511	if (protocol != IPPROTO_UDP && protocol != IPPROTO_TCP) {
1512		printk(KERN_WARNING "svc: only UDP and TCP "
1513				"sockets supported\n");
1514		return ERR_PTR(-EINVAL);
1515	}
1516
1517	type = (protocol == IPPROTO_UDP)? SOCK_DGRAM : SOCK_STREAM;
1518	switch (sin->sa_family) {
1519	case AF_INET6:
1520		family = PF_INET6;
1521		break;
1522	case AF_INET:
1523		family = PF_INET;
1524		break;
1525	default:
1526		return ERR_PTR(-EINVAL);
1527	}
1528
1529	error = __sock_create(net, family, type, protocol, &sock, 1);
1530	if (error < 0)
1531		return ERR_PTR(error);
1532
1533	svc_reclassify_socket(sock);
1534
1535	/*
1536	 * If this is an PF_INET6 listener, we want to avoid
1537	 * getting requests from IPv4 remotes.  Those should
1538	 * be shunted to a PF_INET listener via rpcbind.
1539	 */
1540	val = 1;
1541	if (family == PF_INET6)
1542		kernel_setsockopt(sock, SOL_IPV6, IPV6_V6ONLY,
1543					(char *)&val, sizeof(val));
1544
1545	if (type == SOCK_STREAM)
1546		sock->sk->sk_reuse = 1;		/* allow address reuse */
1547	error = kernel_bind(sock, sin, len);
1548	if (error < 0)
1549		goto bummer;
1550
1551	newlen = len;
1552	error = kernel_getsockname(sock, newsin, &newlen);
1553	if (error < 0)
1554		goto bummer;
1555
1556	if (protocol == IPPROTO_TCP) {
1557		if ((error = kernel_listen(sock, 64)) < 0)
1558			goto bummer;
1559	}
1560
1561	if ((svsk = svc_setup_socket(serv, sock, &error, flags)) != NULL) {
1562		svc_xprt_set_local(&svsk->sk_xprt, newsin, newlen);
1563		return (struct svc_xprt *)svsk;
1564	}
1565
1566bummer:
1567	dprintk("svc: svc_create_socket error = %d\n", -error);
1568	sock_release(sock);
1569	return ERR_PTR(error);
1570}
1571
1572/*
1573 * Detach the svc_sock from the socket so that no
1574 * more callbacks occur.
1575 */
1576static void svc_sock_detach(struct svc_xprt *xprt)
1577{
1578	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1579	struct sock *sk = svsk->sk_sk;
1580	wait_queue_head_t *wq;
1581
1582	dprintk("svc: svc_sock_detach(%p)\n", svsk);
1583
1584	/* put back the old socket callbacks */
1585	sk->sk_state_change = svsk->sk_ostate;
1586	sk->sk_data_ready = svsk->sk_odata;
1587	sk->sk_write_space = svsk->sk_owspace;
1588
1589	wq = sk_sleep(sk);
1590	if (wq && waitqueue_active(wq))
1591		wake_up_interruptible(wq);
1592}
1593
1594/*
1595 * Disconnect the socket, and reset the callbacks
1596 */
1597static void svc_tcp_sock_detach(struct svc_xprt *xprt)
1598{
1599	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1600
1601	dprintk("svc: svc_tcp_sock_detach(%p)\n", svsk);
1602
1603	svc_sock_detach(xprt);
1604
1605	if (!test_bit(XPT_LISTENER, &xprt->xpt_flags)) {
1606		svc_tcp_clear_pages(svsk);
1607		kernel_sock_shutdown(svsk->sk_sock, SHUT_RDWR);
1608	}
1609}
1610
1611/*
1612 * Free the svc_sock's socket resources and the svc_sock itself.
1613 */
1614static void svc_sock_free(struct svc_xprt *xprt)
1615{
1616	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1617	dprintk("svc: svc_sock_free(%p)\n", svsk);
1618
1619	if (svsk->sk_sock->file)
1620		sockfd_put(svsk->sk_sock);
1621	else
1622		sock_release(svsk->sk_sock);
1623	kfree(svsk);
1624}
1625
1626#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1627/*
1628 * Create a back channel svc_xprt which shares the fore channel socket.
1629 */
1630static struct svc_xprt *svc_bc_create_socket(struct svc_serv *serv,
1631					     int protocol,
1632					     struct net *net,
1633					     struct sockaddr *sin, int len,
1634					     int flags)
1635{
1636	struct svc_sock *svsk;
1637	struct svc_xprt *xprt;
1638
1639	if (protocol != IPPROTO_TCP) {
1640		printk(KERN_WARNING "svc: only TCP sockets"
1641			" supported on shared back channel\n");
1642		return ERR_PTR(-EINVAL);
1643	}
1644
1645	svsk = kzalloc(sizeof(*svsk), GFP_KERNEL);
1646	if (!svsk)
1647		return ERR_PTR(-ENOMEM);
1648
1649	xprt = &svsk->sk_xprt;
1650	svc_xprt_init(&svc_tcp_bc_class, xprt, serv);
1651
1652	serv->sv_bc_xprt = xprt;
1653
1654	return xprt;
1655}
1656
1657/*
1658 * Free a back channel svc_sock.
1659 */
1660static void svc_bc_sock_free(struct svc_xprt *xprt)
1661{
1662	if (xprt)
1663		kfree(container_of(xprt, struct svc_sock, sk_xprt));
1664}
1665#endif /* CONFIG_SUNRPC_BACKCHANNEL */
v3.5.6
   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
  47#include <linux/sunrpc/types.h>
  48#include <linux/sunrpc/clnt.h>
  49#include <linux/sunrpc/xdr.h>
  50#include <linux/sunrpc/msg_prot.h>
  51#include <linux/sunrpc/svcsock.h>
  52#include <linux/sunrpc/stats.h>
  53#include <linux/sunrpc/xprt.h>
  54
  55#include "sunrpc.h"
  56
  57#define RPCDBG_FACILITY	RPCDBG_SVCXPRT
  58
  59
  60static struct svc_sock *svc_setup_socket(struct svc_serv *, struct socket *,
  61					 int *errp, int flags);
  62static void		svc_udp_data_ready(struct sock *, int);
  63static int		svc_udp_recvfrom(struct svc_rqst *);
  64static int		svc_udp_sendto(struct svc_rqst *);
  65static void		svc_sock_detach(struct svc_xprt *);
  66static void		svc_tcp_sock_detach(struct svc_xprt *);
  67static void		svc_sock_free(struct svc_xprt *);
  68
  69static struct svc_xprt *svc_create_socket(struct svc_serv *, int,
  70					  struct net *, struct sockaddr *,
  71					  int, int);
  72#if defined(CONFIG_SUNRPC_BACKCHANNEL)
  73static struct svc_xprt *svc_bc_create_socket(struct svc_serv *, int,
  74					     struct net *, struct sockaddr *,
  75					     int, int);
  76static void svc_bc_sock_free(struct svc_xprt *xprt);
  77#endif /* CONFIG_SUNRPC_BACKCHANNEL */
  78
  79#ifdef CONFIG_DEBUG_LOCK_ALLOC
  80static struct lock_class_key svc_key[2];
  81static struct lock_class_key svc_slock_key[2];
  82
  83static void svc_reclassify_socket(struct socket *sock)
  84{
  85	struct sock *sk = sock->sk;
  86	BUG_ON(sock_owned_by_user(sk));
  87	switch (sk->sk_family) {
  88	case AF_INET:
  89		sock_lock_init_class_and_name(sk, "slock-AF_INET-NFSD",
  90					      &svc_slock_key[0],
  91					      "sk_xprt.xpt_lock-AF_INET-NFSD",
  92					      &svc_key[0]);
  93		break;
  94
  95	case AF_INET6:
  96		sock_lock_init_class_and_name(sk, "slock-AF_INET6-NFSD",
  97					      &svc_slock_key[1],
  98					      "sk_xprt.xpt_lock-AF_INET6-NFSD",
  99					      &svc_key[1]);
 100		break;
 101
 102	default:
 103		BUG();
 104	}
 105}
 106#else
 107static void svc_reclassify_socket(struct socket *sock)
 108{
 109}
 110#endif
 111
 112/*
 113 * Release an skbuff after use
 114 */
 115static void svc_release_skb(struct svc_rqst *rqstp)
 116{
 117	struct sk_buff *skb = rqstp->rq_xprt_ctxt;
 118
 119	if (skb) {
 120		struct svc_sock *svsk =
 121			container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 122		rqstp->rq_xprt_ctxt = NULL;
 123
 124		dprintk("svc: service %p, releasing skb %p\n", rqstp, skb);
 125		skb_free_datagram_locked(svsk->sk_sk, skb);
 126	}
 127}
 128
 129union svc_pktinfo_u {
 130	struct in_pktinfo pkti;
 131	struct in6_pktinfo pkti6;
 132};
 133#define SVC_PKTINFO_SPACE \
 134	CMSG_SPACE(sizeof(union svc_pktinfo_u))
 135
 136static void svc_set_cmsg_data(struct svc_rqst *rqstp, struct cmsghdr *cmh)
 137{
 138	struct svc_sock *svsk =
 139		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 140	switch (svsk->sk_sk->sk_family) {
 141	case AF_INET: {
 142			struct in_pktinfo *pki = CMSG_DATA(cmh);
 143
 144			cmh->cmsg_level = SOL_IP;
 145			cmh->cmsg_type = IP_PKTINFO;
 146			pki->ipi_ifindex = 0;
 147			pki->ipi_spec_dst.s_addr =
 148				 svc_daddr_in(rqstp)->sin_addr.s_addr;
 149			cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
 150		}
 151		break;
 152
 153	case AF_INET6: {
 154			struct in6_pktinfo *pki = CMSG_DATA(cmh);
 155			struct sockaddr_in6 *daddr = svc_daddr_in6(rqstp);
 156
 157			cmh->cmsg_level = SOL_IPV6;
 158			cmh->cmsg_type = IPV6_PKTINFO;
 159			pki->ipi6_ifindex = daddr->sin6_scope_id;
 160			pki->ipi6_addr = daddr->sin6_addr;
 
 161			cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
 162		}
 163		break;
 164	}
 165}
 166
 167/*
 168 * send routine intended to be shared by the fore- and back-channel
 169 */
 170int svc_send_common(struct socket *sock, struct xdr_buf *xdr,
 171		    struct page *headpage, unsigned long headoffset,
 172		    struct page *tailpage, unsigned long tailoffset)
 173{
 174	int		result;
 175	int		size;
 176	struct page	**ppage = xdr->pages;
 177	size_t		base = xdr->page_base;
 178	unsigned int	pglen = xdr->page_len;
 179	unsigned int	flags = MSG_MORE;
 180	int		slen;
 181	int		len = 0;
 182
 183	slen = xdr->len;
 184
 185	/* send head */
 186	if (slen == xdr->head[0].iov_len)
 187		flags = 0;
 188	len = kernel_sendpage(sock, headpage, headoffset,
 189				  xdr->head[0].iov_len, flags);
 190	if (len != xdr->head[0].iov_len)
 191		goto out;
 192	slen -= xdr->head[0].iov_len;
 193	if (slen == 0)
 194		goto out;
 195
 196	/* send page data */
 197	size = PAGE_SIZE - base < pglen ? PAGE_SIZE - base : pglen;
 198	while (pglen > 0) {
 199		if (slen == size)
 200			flags = 0;
 201		result = kernel_sendpage(sock, *ppage, base, size, flags);
 202		if (result > 0)
 203			len += result;
 204		if (result != size)
 205			goto out;
 206		slen -= size;
 207		pglen -= size;
 208		size = PAGE_SIZE < pglen ? PAGE_SIZE : pglen;
 209		base = 0;
 210		ppage++;
 211	}
 212
 213	/* send tail */
 214	if (xdr->tail[0].iov_len) {
 215		result = kernel_sendpage(sock, tailpage, tailoffset,
 216				   xdr->tail[0].iov_len, 0);
 217		if (result > 0)
 218			len += result;
 219	}
 220
 221out:
 222	return len;
 223}
 224
 225
 226/*
 227 * Generic sendto routine
 228 */
 229static int svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr)
 230{
 231	struct svc_sock	*svsk =
 232		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 233	struct socket	*sock = svsk->sk_sock;
 234	union {
 235		struct cmsghdr	hdr;
 236		long		all[SVC_PKTINFO_SPACE / sizeof(long)];
 237	} buffer;
 238	struct cmsghdr *cmh = &buffer.hdr;
 239	int		len = 0;
 240	unsigned long tailoff;
 241	unsigned long headoff;
 242	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
 243
 244	if (rqstp->rq_prot == IPPROTO_UDP) {
 245		struct msghdr msg = {
 246			.msg_name	= &rqstp->rq_addr,
 247			.msg_namelen	= rqstp->rq_addrlen,
 248			.msg_control	= cmh,
 249			.msg_controllen	= sizeof(buffer),
 250			.msg_flags	= MSG_MORE,
 251		};
 252
 253		svc_set_cmsg_data(rqstp, cmh);
 254
 255		if (sock_sendmsg(sock, &msg, 0) < 0)
 256			goto out;
 257	}
 258
 259	tailoff = ((unsigned long)xdr->tail[0].iov_base) & (PAGE_SIZE-1);
 260	headoff = 0;
 261	len = svc_send_common(sock, xdr, rqstp->rq_respages[0], headoff,
 262			       rqstp->rq_respages[0], tailoff);
 263
 264out:
 265	dprintk("svc: socket %p sendto([%p %Zu... ], %d) = %d (addr %s)\n",
 266		svsk, xdr->head[0].iov_base, xdr->head[0].iov_len,
 267		xdr->len, len, svc_print_addr(rqstp, buf, sizeof(buf)));
 268
 269	return len;
 270}
 271
 272/*
 273 * Report socket names for nfsdfs
 274 */
 275static int svc_one_sock_name(struct svc_sock *svsk, char *buf, int remaining)
 276{
 277	const struct sock *sk = svsk->sk_sk;
 278	const char *proto_name = sk->sk_protocol == IPPROTO_UDP ?
 279							"udp" : "tcp";
 280	int len;
 281
 282	switch (sk->sk_family) {
 283	case PF_INET:
 284		len = snprintf(buf, remaining, "ipv4 %s %pI4 %d\n",
 285				proto_name,
 286				&inet_sk(sk)->inet_rcv_saddr,
 287				inet_sk(sk)->inet_num);
 288		break;
 289	case PF_INET6:
 290		len = snprintf(buf, remaining, "ipv6 %s %pI6 %d\n",
 291				proto_name,
 292				&inet6_sk(sk)->rcv_saddr,
 293				inet_sk(sk)->inet_num);
 294		break;
 295	default:
 296		len = snprintf(buf, remaining, "*unknown-%d*\n",
 297				sk->sk_family);
 298	}
 299
 300	if (len >= remaining) {
 301		*buf = '\0';
 302		return -ENAMETOOLONG;
 303	}
 304	return len;
 305}
 306
 307/**
 308 * svc_sock_names - construct a list of listener names in a string
 309 * @serv: pointer to RPC service
 310 * @buf: pointer to a buffer to fill in with socket names
 311 * @buflen: size of the buffer to be filled
 312 * @toclose: pointer to '\0'-terminated C string containing the name
 313 *		of a listener to be closed
 314 *
 315 * Fills in @buf with a '\n'-separated list of names of listener
 316 * sockets.  If @toclose is not NULL, the socket named by @toclose
 317 * is closed, and is not included in the output list.
 318 *
 319 * Returns positive length of the socket name string, or a negative
 320 * errno value on error.
 321 */
 322int svc_sock_names(struct svc_serv *serv, char *buf, const size_t buflen,
 323		   const char *toclose)
 324{
 325	struct svc_sock *svsk, *closesk = NULL;
 326	int len = 0;
 327
 328	if (!serv)
 329		return 0;
 330
 331	spin_lock_bh(&serv->sv_lock);
 332	list_for_each_entry(svsk, &serv->sv_permsocks, sk_xprt.xpt_list) {
 333		int onelen = svc_one_sock_name(svsk, buf + len, buflen - len);
 334		if (onelen < 0) {
 335			len = onelen;
 336			break;
 337		}
 338		if (toclose && strcmp(toclose, buf + len) == 0) {
 339			closesk = svsk;
 340			svc_xprt_get(&closesk->sk_xprt);
 341		} else
 342			len += onelen;
 343	}
 344	spin_unlock_bh(&serv->sv_lock);
 345
 346	if (closesk) {
 347		/* Should unregister with portmap, but you cannot
 348		 * unregister just one protocol...
 349		 */
 350		svc_close_xprt(&closesk->sk_xprt);
 351		svc_xprt_put(&closesk->sk_xprt);
 352	} else if (toclose)
 353		return -ENOENT;
 354	return len;
 355}
 356EXPORT_SYMBOL_GPL(svc_sock_names);
 357
 358/*
 359 * Check input queue length
 360 */
 361static int svc_recv_available(struct svc_sock *svsk)
 362{
 363	struct socket	*sock = svsk->sk_sock;
 364	int		avail, err;
 365
 366	err = kernel_sock_ioctl(sock, TIOCINQ, (unsigned long) &avail);
 367
 368	return (err >= 0)? avail : err;
 369}
 370
 371/*
 372 * Generic recvfrom routine.
 373 */
 374static int svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr,
 375			int buflen)
 376{
 377	struct svc_sock *svsk =
 378		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 379	struct msghdr msg = {
 380		.msg_flags	= MSG_DONTWAIT,
 381	};
 382	int len;
 383
 384	rqstp->rq_xprt_hlen = 0;
 385
 386	len = kernel_recvmsg(svsk->sk_sock, &msg, iov, nr, buflen,
 387				msg.msg_flags);
 388
 389	dprintk("svc: socket %p recvfrom(%p, %Zu) = %d\n",
 390		svsk, iov[0].iov_base, iov[0].iov_len, len);
 391	return len;
 392}
 393
 394static int svc_partial_recvfrom(struct svc_rqst *rqstp,
 395				struct kvec *iov, int nr,
 396				int buflen, unsigned int base)
 397{
 398	size_t save_iovlen;
 399	void *save_iovbase;
 400	unsigned int i;
 401	int ret;
 402
 403	if (base == 0)
 404		return svc_recvfrom(rqstp, iov, nr, buflen);
 405
 406	for (i = 0; i < nr; i++) {
 407		if (iov[i].iov_len > base)
 408			break;
 409		base -= iov[i].iov_len;
 410	}
 411	save_iovlen = iov[i].iov_len;
 412	save_iovbase = iov[i].iov_base;
 413	iov[i].iov_len -= base;
 414	iov[i].iov_base += base;
 415	ret = svc_recvfrom(rqstp, &iov[i], nr - i, buflen);
 416	iov[i].iov_len = save_iovlen;
 417	iov[i].iov_base = save_iovbase;
 418	return ret;
 419}
 420
 421/*
 422 * Set socket snd and rcv buffer lengths
 423 */
 424static void svc_sock_setbufsize(struct socket *sock, unsigned int snd,
 425				unsigned int rcv)
 426{
 427#if 0
 428	mm_segment_t	oldfs;
 429	oldfs = get_fs(); set_fs(KERNEL_DS);
 430	sock_setsockopt(sock, SOL_SOCKET, SO_SNDBUF,
 431			(char*)&snd, sizeof(snd));
 432	sock_setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 433			(char*)&rcv, sizeof(rcv));
 434#else
 435	/* sock_setsockopt limits use to sysctl_?mem_max,
 436	 * which isn't acceptable.  Until that is made conditional
 437	 * on not having CAP_SYS_RESOURCE or similar, we go direct...
 438	 * DaveM said I could!
 439	 */
 440	lock_sock(sock->sk);
 441	sock->sk->sk_sndbuf = snd * 2;
 442	sock->sk->sk_rcvbuf = rcv * 2;
 443	sock->sk->sk_write_space(sock->sk);
 444	release_sock(sock->sk);
 445#endif
 446}
 447/*
 448 * INET callback when data has been received on the socket.
 449 */
 450static void svc_udp_data_ready(struct sock *sk, int count)
 451{
 452	struct svc_sock	*svsk = (struct svc_sock *)sk->sk_user_data;
 453	wait_queue_head_t *wq = sk_sleep(sk);
 454
 455	if (svsk) {
 456		dprintk("svc: socket %p(inet %p), count=%d, busy=%d\n",
 457			svsk, sk, count,
 458			test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags));
 459		set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 460		svc_xprt_enqueue(&svsk->sk_xprt);
 461	}
 462	if (wq && waitqueue_active(wq))
 463		wake_up_interruptible(wq);
 464}
 465
 466/*
 467 * INET callback when space is newly available on the socket.
 468 */
 469static void svc_write_space(struct sock *sk)
 470{
 471	struct svc_sock	*svsk = (struct svc_sock *)(sk->sk_user_data);
 472	wait_queue_head_t *wq = sk_sleep(sk);
 473
 474	if (svsk) {
 475		dprintk("svc: socket %p(inet %p), write_space busy=%d\n",
 476			svsk, sk, test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags));
 477		svc_xprt_enqueue(&svsk->sk_xprt);
 478	}
 479
 480	if (wq && waitqueue_active(wq)) {
 481		dprintk("RPC svc_write_space: someone sleeping on %p\n",
 482		       svsk);
 483		wake_up_interruptible(wq);
 484	}
 485}
 486
 487static void svc_tcp_write_space(struct sock *sk)
 488{
 489	struct socket *sock = sk->sk_socket;
 490
 491	if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) && sock)
 492		clear_bit(SOCK_NOSPACE, &sock->flags);
 493	svc_write_space(sk);
 494}
 495
 496/*
 497 * See net/ipv6/ip_sockglue.c : ip_cmsg_recv_pktinfo
 498 */
 499static int svc_udp_get_dest_address4(struct svc_rqst *rqstp,
 500				     struct cmsghdr *cmh)
 501{
 502	struct in_pktinfo *pki = CMSG_DATA(cmh);
 503	struct sockaddr_in *daddr = svc_daddr_in(rqstp);
 504
 505	if (cmh->cmsg_type != IP_PKTINFO)
 506		return 0;
 507
 508	daddr->sin_family = AF_INET;
 509	daddr->sin_addr.s_addr = pki->ipi_spec_dst.s_addr;
 510	return 1;
 511}
 512
 513/*
 514 * See net/ipv6/datagram.c : datagram_recv_ctl
 515 */
 516static int svc_udp_get_dest_address6(struct svc_rqst *rqstp,
 517				     struct cmsghdr *cmh)
 518{
 519	struct in6_pktinfo *pki = CMSG_DATA(cmh);
 520	struct sockaddr_in6 *daddr = svc_daddr_in6(rqstp);
 521
 522	if (cmh->cmsg_type != IPV6_PKTINFO)
 523		return 0;
 524
 525	daddr->sin6_family = AF_INET6;
 526	daddr->sin6_addr = pki->ipi6_addr;
 527	daddr->sin6_scope_id = pki->ipi6_ifindex;
 528	return 1;
 529}
 530
 531/*
 532 * Copy the UDP datagram's destination address to the rqstp structure.
 533 * The 'destination' address in this case is the address to which the
 534 * peer sent the datagram, i.e. our local address. For multihomed
 535 * hosts, this can change from msg to msg. Note that only the IP
 536 * address changes, the port number should remain the same.
 537 */
 538static int svc_udp_get_dest_address(struct svc_rqst *rqstp,
 539				    struct cmsghdr *cmh)
 540{
 541	switch (cmh->cmsg_level) {
 542	case SOL_IP:
 543		return svc_udp_get_dest_address4(rqstp, cmh);
 544	case SOL_IPV6:
 545		return svc_udp_get_dest_address6(rqstp, cmh);
 546	}
 547
 548	return 0;
 549}
 550
 551/*
 552 * Receive a datagram from a UDP socket.
 553 */
 554static int svc_udp_recvfrom(struct svc_rqst *rqstp)
 555{
 556	struct svc_sock	*svsk =
 557		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 558	struct svc_serv	*serv = svsk->sk_xprt.xpt_server;
 559	struct sk_buff	*skb;
 560	union {
 561		struct cmsghdr	hdr;
 562		long		all[SVC_PKTINFO_SPACE / sizeof(long)];
 563	} buffer;
 564	struct cmsghdr *cmh = &buffer.hdr;
 565	struct msghdr msg = {
 566		.msg_name = svc_addr(rqstp),
 567		.msg_control = cmh,
 568		.msg_controllen = sizeof(buffer),
 569		.msg_flags = MSG_DONTWAIT,
 570	};
 571	size_t len;
 572	int err;
 573
 574	if (test_and_clear_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags))
 575	    /* udp sockets need large rcvbuf as all pending
 576	     * requests are still in that buffer.  sndbuf must
 577	     * also be large enough that there is enough space
 578	     * for one reply per thread.  We count all threads
 579	     * rather than threads in a particular pool, which
 580	     * provides an upper bound on the number of threads
 581	     * which will access the socket.
 582	     */
 583	    svc_sock_setbufsize(svsk->sk_sock,
 584				(serv->sv_nrthreads+3) * serv->sv_max_mesg,
 585				(serv->sv_nrthreads+3) * serv->sv_max_mesg);
 586
 587	clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 588	skb = NULL;
 589	err = kernel_recvmsg(svsk->sk_sock, &msg, NULL,
 590			     0, 0, MSG_PEEK | MSG_DONTWAIT);
 591	if (err >= 0)
 592		skb = skb_recv_datagram(svsk->sk_sk, 0, 1, &err);
 593
 594	if (skb == NULL) {
 595		if (err != -EAGAIN) {
 596			/* possibly an icmp error */
 597			dprintk("svc: recvfrom returned error %d\n", -err);
 598			set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 599		}
 600		return -EAGAIN;
 601	}
 602	len = svc_addr_len(svc_addr(rqstp));
 603	if (len == 0)
 604		return -EAFNOSUPPORT;
 605	rqstp->rq_addrlen = len;
 606	if (skb->tstamp.tv64 == 0) {
 607		skb->tstamp = ktime_get_real();
 608		/* Don't enable netstamp, sunrpc doesn't
 609		   need that much accuracy */
 610	}
 611	svsk->sk_sk->sk_stamp = skb->tstamp;
 612	set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); /* there may be more data... */
 613
 614	len  = skb->len - sizeof(struct udphdr);
 615	rqstp->rq_arg.len = len;
 616
 617	rqstp->rq_prot = IPPROTO_UDP;
 618
 619	if (!svc_udp_get_dest_address(rqstp, cmh)) {
 620		net_warn_ratelimited("svc: received unknown control message %d/%d; dropping RPC reply datagram\n",
 621				     cmh->cmsg_level, cmh->cmsg_type);
 
 
 
 622		skb_free_datagram_locked(svsk->sk_sk, skb);
 623		return 0;
 624	}
 625	rqstp->rq_daddrlen = svc_addr_len(svc_daddr(rqstp));
 626
 627	if (skb_is_nonlinear(skb)) {
 628		/* we have to copy */
 629		local_bh_disable();
 630		if (csum_partial_copy_to_xdr(&rqstp->rq_arg, skb)) {
 631			local_bh_enable();
 632			/* checksum error */
 633			skb_free_datagram_locked(svsk->sk_sk, skb);
 634			return 0;
 635		}
 636		local_bh_enable();
 637		skb_free_datagram_locked(svsk->sk_sk, skb);
 638	} else {
 639		/* we can use it in-place */
 640		rqstp->rq_arg.head[0].iov_base = skb->data +
 641			sizeof(struct udphdr);
 642		rqstp->rq_arg.head[0].iov_len = len;
 643		if (skb_checksum_complete(skb)) {
 644			skb_free_datagram_locked(svsk->sk_sk, skb);
 645			return 0;
 646		}
 647		rqstp->rq_xprt_ctxt = skb;
 648	}
 649
 650	rqstp->rq_arg.page_base = 0;
 651	if (len <= rqstp->rq_arg.head[0].iov_len) {
 652		rqstp->rq_arg.head[0].iov_len = len;
 653		rqstp->rq_arg.page_len = 0;
 654		rqstp->rq_respages = rqstp->rq_pages+1;
 655	} else {
 656		rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len;
 657		rqstp->rq_respages = rqstp->rq_pages + 1 +
 658			DIV_ROUND_UP(rqstp->rq_arg.page_len, PAGE_SIZE);
 659	}
 660
 661	if (serv->sv_stats)
 662		serv->sv_stats->netudpcnt++;
 663
 664	return len;
 665}
 666
 667static int
 668svc_udp_sendto(struct svc_rqst *rqstp)
 669{
 670	int		error;
 671
 672	error = svc_sendto(rqstp, &rqstp->rq_res);
 673	if (error == -ECONNREFUSED)
 674		/* ICMP error on earlier request. */
 675		error = svc_sendto(rqstp, &rqstp->rq_res);
 676
 677	return error;
 678}
 679
 680static void svc_udp_prep_reply_hdr(struct svc_rqst *rqstp)
 681{
 682}
 683
 684static int svc_udp_has_wspace(struct svc_xprt *xprt)
 685{
 686	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
 687	struct svc_serv	*serv = xprt->xpt_server;
 688	unsigned long required;
 689
 690	/*
 691	 * Set the SOCK_NOSPACE flag before checking the available
 692	 * sock space.
 693	 */
 694	set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
 695	required = atomic_read(&svsk->sk_xprt.xpt_reserved) + serv->sv_max_mesg;
 696	if (required*2 > sock_wspace(svsk->sk_sk))
 697		return 0;
 698	clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
 699	return 1;
 700}
 701
 702static struct svc_xprt *svc_udp_accept(struct svc_xprt *xprt)
 703{
 704	BUG();
 705	return NULL;
 706}
 707
 708static struct svc_xprt *svc_udp_create(struct svc_serv *serv,
 709				       struct net *net,
 710				       struct sockaddr *sa, int salen,
 711				       int flags)
 712{
 713	return svc_create_socket(serv, IPPROTO_UDP, net, sa, salen, flags);
 714}
 715
 716static struct svc_xprt_ops svc_udp_ops = {
 717	.xpo_create = svc_udp_create,
 718	.xpo_recvfrom = svc_udp_recvfrom,
 719	.xpo_sendto = svc_udp_sendto,
 720	.xpo_release_rqst = svc_release_skb,
 721	.xpo_detach = svc_sock_detach,
 722	.xpo_free = svc_sock_free,
 723	.xpo_prep_reply_hdr = svc_udp_prep_reply_hdr,
 724	.xpo_has_wspace = svc_udp_has_wspace,
 725	.xpo_accept = svc_udp_accept,
 726};
 727
 728static struct svc_xprt_class svc_udp_class = {
 729	.xcl_name = "udp",
 730	.xcl_owner = THIS_MODULE,
 731	.xcl_ops = &svc_udp_ops,
 732	.xcl_max_payload = RPCSVC_MAXPAYLOAD_UDP,
 733};
 734
 735static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv)
 736{
 737	int err, level, optname, one = 1;
 738
 739	svc_xprt_init(sock_net(svsk->sk_sock->sk), &svc_udp_class,
 740		      &svsk->sk_xprt, serv);
 741	clear_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
 742	svsk->sk_sk->sk_data_ready = svc_udp_data_ready;
 743	svsk->sk_sk->sk_write_space = svc_write_space;
 744
 745	/* initialise setting must have enough space to
 746	 * receive and respond to one request.
 747	 * svc_udp_recvfrom will re-adjust if necessary
 748	 */
 749	svc_sock_setbufsize(svsk->sk_sock,
 750			    3 * svsk->sk_xprt.xpt_server->sv_max_mesg,
 751			    3 * svsk->sk_xprt.xpt_server->sv_max_mesg);
 752
 753	/* data might have come in before data_ready set up */
 754	set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 755	set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
 756
 757	/* make sure we get destination address info */
 758	switch (svsk->sk_sk->sk_family) {
 759	case AF_INET:
 760		level = SOL_IP;
 761		optname = IP_PKTINFO;
 762		break;
 763	case AF_INET6:
 764		level = SOL_IPV6;
 765		optname = IPV6_RECVPKTINFO;
 766		break;
 767	default:
 768		BUG();
 769	}
 770	err = kernel_setsockopt(svsk->sk_sock, level, optname,
 771					(char *)&one, sizeof(one));
 772	dprintk("svc: kernel_setsockopt returned %d\n", err);
 773}
 774
 775/*
 776 * A data_ready event on a listening socket means there's a connection
 777 * pending. Do not use state_change as a substitute for it.
 778 */
 779static void svc_tcp_listen_data_ready(struct sock *sk, int count_unused)
 780{
 781	struct svc_sock	*svsk = (struct svc_sock *)sk->sk_user_data;
 782	wait_queue_head_t *wq;
 783
 784	dprintk("svc: socket %p TCP (listen) state change %d\n",
 785		sk, sk->sk_state);
 786
 787	/*
 788	 * This callback may called twice when a new connection
 789	 * is established as a child socket inherits everything
 790	 * from a parent LISTEN socket.
 791	 * 1) data_ready method of the parent socket will be called
 792	 *    when one of child sockets become ESTABLISHED.
 793	 * 2) data_ready method of the child socket may be called
 794	 *    when it receives data before the socket is accepted.
 795	 * In case of 2, we should ignore it silently.
 796	 */
 797	if (sk->sk_state == TCP_LISTEN) {
 798		if (svsk) {
 799			set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
 800			svc_xprt_enqueue(&svsk->sk_xprt);
 801		} else
 802			printk("svc: socket %p: no user data\n", sk);
 803	}
 804
 805	wq = sk_sleep(sk);
 806	if (wq && waitqueue_active(wq))
 807		wake_up_interruptible_all(wq);
 808}
 809
 810/*
 811 * A state change on a connected socket means it's dying or dead.
 812 */
 813static void svc_tcp_state_change(struct sock *sk)
 814{
 815	struct svc_sock	*svsk = (struct svc_sock *)sk->sk_user_data;
 816	wait_queue_head_t *wq = sk_sleep(sk);
 817
 818	dprintk("svc: socket %p TCP (connected) state change %d (svsk %p)\n",
 819		sk, sk->sk_state, sk->sk_user_data);
 820
 821	if (!svsk)
 822		printk("svc: socket %p: no user data\n", sk);
 823	else {
 824		set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
 825		svc_xprt_enqueue(&svsk->sk_xprt);
 826	}
 827	if (wq && waitqueue_active(wq))
 828		wake_up_interruptible_all(wq);
 829}
 830
 831static void svc_tcp_data_ready(struct sock *sk, int count)
 832{
 833	struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
 834	wait_queue_head_t *wq = sk_sleep(sk);
 835
 836	dprintk("svc: socket %p TCP data ready (svsk %p)\n",
 837		sk, sk->sk_user_data);
 838	if (svsk) {
 839		set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 840		svc_xprt_enqueue(&svsk->sk_xprt);
 841	}
 842	if (wq && waitqueue_active(wq))
 843		wake_up_interruptible(wq);
 844}
 845
 846/*
 847 * Accept a TCP connection
 848 */
 849static struct svc_xprt *svc_tcp_accept(struct svc_xprt *xprt)
 850{
 851	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
 852	struct sockaddr_storage addr;
 853	struct sockaddr	*sin = (struct sockaddr *) &addr;
 854	struct svc_serv	*serv = svsk->sk_xprt.xpt_server;
 855	struct socket	*sock = svsk->sk_sock;
 856	struct socket	*newsock;
 857	struct svc_sock	*newsvsk;
 858	int		err, slen;
 859	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
 860
 861	dprintk("svc: tcp_accept %p sock %p\n", svsk, sock);
 862	if (!sock)
 863		return NULL;
 864
 865	clear_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
 866	err = kernel_accept(sock, &newsock, O_NONBLOCK);
 867	if (err < 0) {
 868		if (err == -ENOMEM)
 869			printk(KERN_WARNING "%s: no more sockets!\n",
 870			       serv->sv_name);
 871		else if (err != -EAGAIN)
 872			net_warn_ratelimited("%s: accept failed (err %d)!\n",
 873					     serv->sv_name, -err);
 874		return NULL;
 875	}
 876	set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
 877
 878	err = kernel_getpeername(newsock, sin, &slen);
 879	if (err < 0) {
 880		net_warn_ratelimited("%s: peername failed (err %d)!\n",
 881				     serv->sv_name, -err);
 
 882		goto failed;		/* aborted connection or whatever */
 883	}
 884
 885	/* Ideally, we would want to reject connections from unauthorized
 886	 * hosts here, but when we get encryption, the IP of the host won't
 887	 * tell us anything.  For now just warn about unpriv connections.
 888	 */
 889	if (!svc_port_is_privileged(sin)) {
 890		dprintk(KERN_WARNING
 891			"%s: connect from unprivileged port: %s\n",
 892			serv->sv_name,
 893			__svc_print_addr(sin, buf, sizeof(buf)));
 894	}
 895	dprintk("%s: connect from %s\n", serv->sv_name,
 896		__svc_print_addr(sin, buf, sizeof(buf)));
 897
 898	/* make sure that a write doesn't block forever when
 899	 * low on memory
 900	 */
 901	newsock->sk->sk_sndtimeo = HZ*30;
 902
 903	if (!(newsvsk = svc_setup_socket(serv, newsock, &err,
 904				 (SVC_SOCK_ANONYMOUS | SVC_SOCK_TEMPORARY))))
 905		goto failed;
 906	svc_xprt_set_remote(&newsvsk->sk_xprt, sin, slen);
 907	err = kernel_getsockname(newsock, sin, &slen);
 908	if (unlikely(err < 0)) {
 909		dprintk("svc_tcp_accept: kernel_getsockname error %d\n", -err);
 910		slen = offsetof(struct sockaddr, sa_data);
 911	}
 912	svc_xprt_set_local(&newsvsk->sk_xprt, sin, slen);
 913
 914	if (serv->sv_stats)
 915		serv->sv_stats->nettcpconn++;
 916
 917	return &newsvsk->sk_xprt;
 918
 919failed:
 920	sock_release(newsock);
 921	return NULL;
 922}
 923
 924static unsigned int svc_tcp_restore_pages(struct svc_sock *svsk, struct svc_rqst *rqstp)
 925{
 926	unsigned int i, len, npages;
 927
 928	if (svsk->sk_tcplen <= sizeof(rpc_fraghdr))
 929		return 0;
 930	len = svsk->sk_tcplen - sizeof(rpc_fraghdr);
 931	npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
 932	for (i = 0; i < npages; i++) {
 933		if (rqstp->rq_pages[i] != NULL)
 934			put_page(rqstp->rq_pages[i]);
 935		BUG_ON(svsk->sk_pages[i] == NULL);
 936		rqstp->rq_pages[i] = svsk->sk_pages[i];
 937		svsk->sk_pages[i] = NULL;
 938	}
 939	rqstp->rq_arg.head[0].iov_base = page_address(rqstp->rq_pages[0]);
 940	return len;
 941}
 942
 943static void svc_tcp_save_pages(struct svc_sock *svsk, struct svc_rqst *rqstp)
 944{
 945	unsigned int i, len, npages;
 946
 947	if (svsk->sk_tcplen <= sizeof(rpc_fraghdr))
 948		return;
 949	len = svsk->sk_tcplen - sizeof(rpc_fraghdr);
 950	npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
 951	for (i = 0; i < npages; i++) {
 952		svsk->sk_pages[i] = rqstp->rq_pages[i];
 953		rqstp->rq_pages[i] = NULL;
 954	}
 955}
 956
 957static void svc_tcp_clear_pages(struct svc_sock *svsk)
 958{
 959	unsigned int i, len, npages;
 960
 961	if (svsk->sk_tcplen <= sizeof(rpc_fraghdr))
 962		goto out;
 963	len = svsk->sk_tcplen - sizeof(rpc_fraghdr);
 964	npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
 965	for (i = 0; i < npages; i++) {
 966		BUG_ON(svsk->sk_pages[i] == NULL);
 967		put_page(svsk->sk_pages[i]);
 968		svsk->sk_pages[i] = NULL;
 969	}
 970out:
 971	svsk->sk_tcplen = 0;
 972}
 973
 974/*
 975 * Receive data.
 976 * If we haven't gotten the record length yet, get the next four bytes.
 977 * Otherwise try to gobble up as much as possible up to the complete
 978 * record length.
 979 */
 980static int svc_tcp_recv_record(struct svc_sock *svsk, struct svc_rqst *rqstp)
 981{
 982	struct svc_serv	*serv = svsk->sk_xprt.xpt_server;
 983	unsigned int want;
 984	int len;
 985
 986	clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 987
 988	if (svsk->sk_tcplen < sizeof(rpc_fraghdr)) {
 989		struct kvec	iov;
 990
 991		want = sizeof(rpc_fraghdr) - svsk->sk_tcplen;
 992		iov.iov_base = ((char *) &svsk->sk_reclen) + svsk->sk_tcplen;
 993		iov.iov_len  = want;
 994		if ((len = svc_recvfrom(rqstp, &iov, 1, want)) < 0)
 995			goto error;
 996		svsk->sk_tcplen += len;
 997
 998		if (len < want) {
 999			dprintk("svc: short recvfrom while reading record "
1000				"length (%d of %d)\n", len, want);
1001			return -EAGAIN;
1002		}
1003
1004		svsk->sk_reclen = ntohl(svsk->sk_reclen);
1005		if (!(svsk->sk_reclen & RPC_LAST_STREAM_FRAGMENT)) {
1006			/* FIXME: technically, a record can be fragmented,
1007			 *  and non-terminal fragments will not have the top
1008			 *  bit set in the fragment length header.
1009			 *  But apparently no known nfs clients send fragmented
1010			 *  records. */
1011			net_notice_ratelimited("RPC: multiple fragments per record not supported\n");
 
 
1012			goto err_delete;
1013		}
1014
1015		svsk->sk_reclen &= RPC_FRAGMENT_SIZE_MASK;
1016		dprintk("svc: TCP record, %d bytes\n", svsk->sk_reclen);
1017		if (svsk->sk_reclen > serv->sv_max_mesg) {
1018			net_notice_ratelimited("RPC: fragment too large: 0x%08lx\n",
1019					       (unsigned long)svsk->sk_reclen);
 
 
1020			goto err_delete;
1021		}
1022	}
1023
1024	if (svsk->sk_reclen < 8)
1025		goto err_delete; /* client is nuts. */
1026
1027	len = svsk->sk_reclen;
1028
1029	return len;
1030error:
1031	dprintk("RPC: TCP recv_record got %d\n", len);
1032	return len;
1033err_delete:
1034	set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1035	return -EAGAIN;
1036}
1037
1038static int receive_cb_reply(struct svc_sock *svsk, struct svc_rqst *rqstp)
1039{
1040	struct rpc_xprt *bc_xprt = svsk->sk_xprt.xpt_bc_xprt;
1041	struct rpc_rqst *req = NULL;
1042	struct kvec *src, *dst;
1043	__be32 *p = (__be32 *)rqstp->rq_arg.head[0].iov_base;
1044	__be32 xid;
1045	__be32 calldir;
1046
1047	xid = *p++;
1048	calldir = *p;
1049
1050	if (bc_xprt)
1051		req = xprt_lookup_rqst(bc_xprt, xid);
1052
1053	if (!req) {
1054		printk(KERN_NOTICE
1055			"%s: Got unrecognized reply: "
1056			"calldir 0x%x xpt_bc_xprt %p xid %08x\n",
1057			__func__, ntohl(calldir),
1058			bc_xprt, xid);
1059		return -EAGAIN;
1060	}
1061
1062	memcpy(&req->rq_private_buf, &req->rq_rcv_buf, sizeof(struct xdr_buf));
1063	/*
1064	 * XXX!: cheating for now!  Only copying HEAD.
1065	 * But we know this is good enough for now (in fact, for any
1066	 * callback reply in the forseeable future).
1067	 */
1068	dst = &req->rq_private_buf.head[0];
1069	src = &rqstp->rq_arg.head[0];
1070	if (dst->iov_len < src->iov_len)
1071		return -EAGAIN; /* whatever; just giving up. */
1072	memcpy(dst->iov_base, src->iov_base, src->iov_len);
1073	xprt_complete_rqst(req->rq_task, svsk->sk_reclen);
1074	rqstp->rq_arg.len = 0;
1075	return 0;
1076}
1077
1078static int copy_pages_to_kvecs(struct kvec *vec, struct page **pages, int len)
1079{
1080	int i = 0;
1081	int t = 0;
1082
1083	while (t < len) {
1084		vec[i].iov_base = page_address(pages[i]);
1085		vec[i].iov_len = PAGE_SIZE;
1086		i++;
1087		t += PAGE_SIZE;
1088	}
1089	return i;
1090}
1091
1092
1093/*
1094 * Receive data from a TCP socket.
1095 */
1096static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
1097{
1098	struct svc_sock	*svsk =
1099		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
1100	struct svc_serv	*serv = svsk->sk_xprt.xpt_server;
1101	int		len;
1102	struct kvec *vec;
1103	unsigned int want, base;
1104	__be32 *p;
1105	__be32 calldir;
1106	int pnum;
1107
1108	dprintk("svc: tcp_recv %p data %d conn %d close %d\n",
1109		svsk, test_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags),
1110		test_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags),
1111		test_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags));
1112
1113	len = svc_tcp_recv_record(svsk, rqstp);
1114	if (len < 0)
1115		goto error;
1116
1117	base = svc_tcp_restore_pages(svsk, rqstp);
1118	want = svsk->sk_reclen - base;
1119
1120	vec = rqstp->rq_vec;
1121
1122	pnum = copy_pages_to_kvecs(&vec[0], &rqstp->rq_pages[0],
1123						svsk->sk_reclen);
1124
1125	rqstp->rq_respages = &rqstp->rq_pages[pnum];
1126
1127	/* Now receive data */
1128	len = svc_partial_recvfrom(rqstp, vec, pnum, want, base);
1129	if (len >= 0)
1130		svsk->sk_tcplen += len;
1131	if (len != want) {
1132		svc_tcp_save_pages(svsk, rqstp);
1133		if (len < 0 && len != -EAGAIN)
1134			goto err_other;
 
1135		dprintk("svc: incomplete TCP record (%d of %d)\n",
1136			svsk->sk_tcplen, svsk->sk_reclen);
1137		goto err_noclose;
1138	}
1139
1140	rqstp->rq_arg.len = svsk->sk_reclen;
1141	rqstp->rq_arg.page_base = 0;
1142	if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len) {
1143		rqstp->rq_arg.head[0].iov_len = rqstp->rq_arg.len;
1144		rqstp->rq_arg.page_len = 0;
1145	} else
1146		rqstp->rq_arg.page_len = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len;
1147
1148	rqstp->rq_xprt_ctxt   = NULL;
1149	rqstp->rq_prot	      = IPPROTO_TCP;
1150
1151	p = (__be32 *)rqstp->rq_arg.head[0].iov_base;
1152	calldir = p[1];
1153	if (calldir)
1154		len = receive_cb_reply(svsk, rqstp);
1155
1156	/* Reset TCP read info */
1157	svsk->sk_reclen = 0;
1158	svsk->sk_tcplen = 0;
1159	/* If we have more data, signal svc_xprt_enqueue() to try again */
1160	if (svc_recv_available(svsk) > sizeof(rpc_fraghdr))
1161		set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
1162
1163	if (len < 0)
1164		goto error;
1165
1166	svc_xprt_copy_addrs(rqstp, &svsk->sk_xprt);
1167	if (serv->sv_stats)
1168		serv->sv_stats->nettcpcnt++;
1169
1170	dprintk("svc: TCP complete record (%d bytes)\n", rqstp->rq_arg.len);
1171	return rqstp->rq_arg.len;
1172
1173error:
1174	if (len != -EAGAIN)
1175		goto err_other;
1176	dprintk("RPC: TCP recvfrom got EAGAIN\n");
1177	return -EAGAIN;
1178err_other:
1179	printk(KERN_NOTICE "%s: recvfrom returned errno %d\n",
1180	       svsk->sk_xprt.xpt_server->sv_name, -len);
1181	set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1182err_noclose:
1183	return -EAGAIN;	/* record not complete */
1184}
1185
1186/*
1187 * Send out data on TCP socket.
1188 */
1189static int svc_tcp_sendto(struct svc_rqst *rqstp)
1190{
1191	struct xdr_buf	*xbufp = &rqstp->rq_res;
1192	int sent;
1193	__be32 reclen;
1194
1195	/* Set up the first element of the reply kvec.
1196	 * Any other kvecs that may be in use have been taken
1197	 * care of by the server implementation itself.
1198	 */
1199	reclen = htonl(0x80000000|((xbufp->len ) - 4));
1200	memcpy(xbufp->head[0].iov_base, &reclen, 4);
1201
1202	sent = svc_sendto(rqstp, &rqstp->rq_res);
1203	if (sent != xbufp->len) {
1204		printk(KERN_NOTICE
1205		       "rpc-srv/tcp: %s: %s %d when sending %d bytes "
1206		       "- shutting down socket\n",
1207		       rqstp->rq_xprt->xpt_server->sv_name,
1208		       (sent<0)?"got error":"sent only",
1209		       sent, xbufp->len);
1210		set_bit(XPT_CLOSE, &rqstp->rq_xprt->xpt_flags);
1211		svc_xprt_enqueue(rqstp->rq_xprt);
1212		sent = -EAGAIN;
1213	}
1214	return sent;
1215}
1216
1217/*
1218 * Setup response header. TCP has a 4B record length field.
1219 */
1220static void svc_tcp_prep_reply_hdr(struct svc_rqst *rqstp)
1221{
1222	struct kvec *resv = &rqstp->rq_res.head[0];
1223
1224	/* tcp needs a space for the record length... */
1225	svc_putnl(resv, 0);
1226}
1227
1228static int svc_tcp_has_wspace(struct svc_xprt *xprt)
1229{
1230	struct svc_sock *svsk =	container_of(xprt, struct svc_sock, sk_xprt);
1231	struct svc_serv *serv = svsk->sk_xprt.xpt_server;
1232	int required;
1233
1234	if (test_bit(XPT_LISTENER, &xprt->xpt_flags))
1235		return 1;
1236	required = atomic_read(&xprt->xpt_reserved) + serv->sv_max_mesg;
1237	if (sk_stream_wspace(svsk->sk_sk) >= required)
1238		return 1;
1239	set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
1240	return 0;
1241}
1242
1243static struct svc_xprt *svc_tcp_create(struct svc_serv *serv,
1244				       struct net *net,
1245				       struct sockaddr *sa, int salen,
1246				       int flags)
1247{
1248	return svc_create_socket(serv, IPPROTO_TCP, net, sa, salen, flags);
1249}
1250
1251#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1252static struct svc_xprt *svc_bc_create_socket(struct svc_serv *, int,
1253					     struct net *, struct sockaddr *,
1254					     int, int);
1255static void svc_bc_sock_free(struct svc_xprt *xprt);
1256
1257static struct svc_xprt *svc_bc_tcp_create(struct svc_serv *serv,
1258				       struct net *net,
1259				       struct sockaddr *sa, int salen,
1260				       int flags)
1261{
1262	return svc_bc_create_socket(serv, IPPROTO_TCP, net, sa, salen, flags);
1263}
1264
1265static void svc_bc_tcp_sock_detach(struct svc_xprt *xprt)
1266{
1267}
1268
1269static struct svc_xprt_ops svc_tcp_bc_ops = {
1270	.xpo_create = svc_bc_tcp_create,
1271	.xpo_detach = svc_bc_tcp_sock_detach,
1272	.xpo_free = svc_bc_sock_free,
1273	.xpo_prep_reply_hdr = svc_tcp_prep_reply_hdr,
1274};
1275
1276static struct svc_xprt_class svc_tcp_bc_class = {
1277	.xcl_name = "tcp-bc",
1278	.xcl_owner = THIS_MODULE,
1279	.xcl_ops = &svc_tcp_bc_ops,
1280	.xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP,
1281};
1282
1283static void svc_init_bc_xprt_sock(void)
1284{
1285	svc_reg_xprt_class(&svc_tcp_bc_class);
1286}
1287
1288static void svc_cleanup_bc_xprt_sock(void)
1289{
1290	svc_unreg_xprt_class(&svc_tcp_bc_class);
1291}
1292#else /* CONFIG_SUNRPC_BACKCHANNEL */
1293static void svc_init_bc_xprt_sock(void)
1294{
1295}
1296
1297static void svc_cleanup_bc_xprt_sock(void)
1298{
1299}
1300#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1301
1302static struct svc_xprt_ops svc_tcp_ops = {
1303	.xpo_create = svc_tcp_create,
1304	.xpo_recvfrom = svc_tcp_recvfrom,
1305	.xpo_sendto = svc_tcp_sendto,
1306	.xpo_release_rqst = svc_release_skb,
1307	.xpo_detach = svc_tcp_sock_detach,
1308	.xpo_free = svc_sock_free,
1309	.xpo_prep_reply_hdr = svc_tcp_prep_reply_hdr,
1310	.xpo_has_wspace = svc_tcp_has_wspace,
1311	.xpo_accept = svc_tcp_accept,
1312};
1313
1314static struct svc_xprt_class svc_tcp_class = {
1315	.xcl_name = "tcp",
1316	.xcl_owner = THIS_MODULE,
1317	.xcl_ops = &svc_tcp_ops,
1318	.xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP,
1319};
1320
1321void svc_init_xprt_sock(void)
1322{
1323	svc_reg_xprt_class(&svc_tcp_class);
1324	svc_reg_xprt_class(&svc_udp_class);
1325	svc_init_bc_xprt_sock();
1326}
1327
1328void svc_cleanup_xprt_sock(void)
1329{
1330	svc_unreg_xprt_class(&svc_tcp_class);
1331	svc_unreg_xprt_class(&svc_udp_class);
1332	svc_cleanup_bc_xprt_sock();
1333}
1334
1335static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv)
1336{
1337	struct sock	*sk = svsk->sk_sk;
1338
1339	svc_xprt_init(sock_net(svsk->sk_sock->sk), &svc_tcp_class,
1340		      &svsk->sk_xprt, serv);
1341	set_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
1342	if (sk->sk_state == TCP_LISTEN) {
1343		dprintk("setting up TCP socket for listening\n");
1344		set_bit(XPT_LISTENER, &svsk->sk_xprt.xpt_flags);
1345		sk->sk_data_ready = svc_tcp_listen_data_ready;
1346		set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
1347	} else {
1348		dprintk("setting up TCP socket for reading\n");
1349		sk->sk_state_change = svc_tcp_state_change;
1350		sk->sk_data_ready = svc_tcp_data_ready;
1351		sk->sk_write_space = svc_tcp_write_space;
1352
1353		svsk->sk_reclen = 0;
1354		svsk->sk_tcplen = 0;
1355		memset(&svsk->sk_pages[0], 0, sizeof(svsk->sk_pages));
1356
1357		tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
1358
1359		set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
1360		if (sk->sk_state != TCP_ESTABLISHED)
1361			set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1362	}
1363}
1364
1365void svc_sock_update_bufs(struct svc_serv *serv)
1366{
1367	/*
1368	 * The number of server threads has changed. Update
1369	 * rcvbuf and sndbuf accordingly on all sockets
1370	 */
1371	struct svc_sock *svsk;
1372
1373	spin_lock_bh(&serv->sv_lock);
1374	list_for_each_entry(svsk, &serv->sv_permsocks, sk_xprt.xpt_list)
1375		set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
 
 
1376	spin_unlock_bh(&serv->sv_lock);
1377}
1378EXPORT_SYMBOL_GPL(svc_sock_update_bufs);
1379
1380/*
1381 * Initialize socket for RPC use and create svc_sock struct
1382 * XXX: May want to setsockopt SO_SNDBUF and SO_RCVBUF.
1383 */
1384static struct svc_sock *svc_setup_socket(struct svc_serv *serv,
1385						struct socket *sock,
1386						int *errp, int flags)
1387{
1388	struct svc_sock	*svsk;
1389	struct sock	*inet;
1390	int		pmap_register = !(flags & SVC_SOCK_ANONYMOUS);
1391
1392	dprintk("svc: svc_setup_socket %p\n", sock);
1393	if (!(svsk = kzalloc(sizeof(*svsk), GFP_KERNEL))) {
1394		*errp = -ENOMEM;
1395		return NULL;
1396	}
1397
1398	inet = sock->sk;
1399
1400	/* Register socket with portmapper */
1401	if (*errp >= 0 && pmap_register)
1402		*errp = svc_register(serv, sock_net(sock->sk), inet->sk_family,
1403				     inet->sk_protocol,
1404				     ntohs(inet_sk(inet)->inet_sport));
1405
1406	if (*errp < 0) {
1407		kfree(svsk);
1408		return NULL;
1409	}
1410
1411	inet->sk_user_data = svsk;
1412	svsk->sk_sock = sock;
1413	svsk->sk_sk = inet;
1414	svsk->sk_ostate = inet->sk_state_change;
1415	svsk->sk_odata = inet->sk_data_ready;
1416	svsk->sk_owspace = inet->sk_write_space;
1417
1418	/* Initialize the socket */
1419	if (sock->type == SOCK_DGRAM)
1420		svc_udp_init(svsk, serv);
1421	else {
1422		/* initialise setting must have enough space to
1423		 * receive and respond to one request.
1424		 */
1425		svc_sock_setbufsize(svsk->sk_sock, 4 * serv->sv_max_mesg,
1426					4 * serv->sv_max_mesg);
1427		svc_tcp_init(svsk, serv);
1428	}
1429
1430	dprintk("svc: svc_setup_socket created %p (inet %p)\n",
1431				svsk, svsk->sk_sk);
1432
1433	return svsk;
1434}
1435
1436/**
1437 * svc_addsock - add a listener socket to an RPC service
1438 * @serv: pointer to RPC service to which to add a new listener
1439 * @fd: file descriptor of the new listener
1440 * @name_return: pointer to buffer to fill in with name of listener
1441 * @len: size of the buffer
1442 *
1443 * Fills in socket name and returns positive length of name if successful.
1444 * Name is terminated with '\n'.  On error, returns a negative errno
1445 * value.
1446 */
1447int svc_addsock(struct svc_serv *serv, const int fd, char *name_return,
1448		const size_t len)
1449{
1450	int err = 0;
1451	struct socket *so = sockfd_lookup(fd, &err);
1452	struct svc_sock *svsk = NULL;
1453
1454	if (!so)
1455		return err;
1456	if ((so->sk->sk_family != PF_INET) && (so->sk->sk_family != PF_INET6))
1457		err =  -EAFNOSUPPORT;
1458	else if (so->sk->sk_protocol != IPPROTO_TCP &&
1459	    so->sk->sk_protocol != IPPROTO_UDP)
1460		err =  -EPROTONOSUPPORT;
1461	else if (so->state > SS_UNCONNECTED)
1462		err = -EISCONN;
1463	else {
1464		if (!try_module_get(THIS_MODULE))
1465			err = -ENOENT;
1466		else
1467			svsk = svc_setup_socket(serv, so, &err,
1468						SVC_SOCK_DEFAULTS);
1469		if (svsk) {
1470			struct sockaddr_storage addr;
1471			struct sockaddr *sin = (struct sockaddr *)&addr;
1472			int salen;
1473			if (kernel_getsockname(svsk->sk_sock, sin, &salen) == 0)
1474				svc_xprt_set_local(&svsk->sk_xprt, sin, salen);
1475			clear_bit(XPT_TEMP, &svsk->sk_xprt.xpt_flags);
1476			spin_lock_bh(&serv->sv_lock);
1477			list_add(&svsk->sk_xprt.xpt_list, &serv->sv_permsocks);
1478			spin_unlock_bh(&serv->sv_lock);
1479			svc_xprt_received(&svsk->sk_xprt);
1480			err = 0;
1481		} else
1482			module_put(THIS_MODULE);
1483	}
1484	if (err) {
1485		sockfd_put(so);
1486		return err;
1487	}
1488	return svc_one_sock_name(svsk, name_return, len);
1489}
1490EXPORT_SYMBOL_GPL(svc_addsock);
1491
1492/*
1493 * Create socket for RPC service.
1494 */
1495static struct svc_xprt *svc_create_socket(struct svc_serv *serv,
1496					  int protocol,
1497					  struct net *net,
1498					  struct sockaddr *sin, int len,
1499					  int flags)
1500{
1501	struct svc_sock	*svsk;
1502	struct socket	*sock;
1503	int		error;
1504	int		type;
1505	struct sockaddr_storage addr;
1506	struct sockaddr *newsin = (struct sockaddr *)&addr;
1507	int		newlen;
1508	int		family;
1509	int		val;
1510	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
1511
1512	dprintk("svc: svc_create_socket(%s, %d, %s)\n",
1513			serv->sv_program->pg_name, protocol,
1514			__svc_print_addr(sin, buf, sizeof(buf)));
1515
1516	if (protocol != IPPROTO_UDP && protocol != IPPROTO_TCP) {
1517		printk(KERN_WARNING "svc: only UDP and TCP "
1518				"sockets supported\n");
1519		return ERR_PTR(-EINVAL);
1520	}
1521
1522	type = (protocol == IPPROTO_UDP)? SOCK_DGRAM : SOCK_STREAM;
1523	switch (sin->sa_family) {
1524	case AF_INET6:
1525		family = PF_INET6;
1526		break;
1527	case AF_INET:
1528		family = PF_INET;
1529		break;
1530	default:
1531		return ERR_PTR(-EINVAL);
1532	}
1533
1534	error = __sock_create(net, family, type, protocol, &sock, 1);
1535	if (error < 0)
1536		return ERR_PTR(error);
1537
1538	svc_reclassify_socket(sock);
1539
1540	/*
1541	 * If this is an PF_INET6 listener, we want to avoid
1542	 * getting requests from IPv4 remotes.  Those should
1543	 * be shunted to a PF_INET listener via rpcbind.
1544	 */
1545	val = 1;
1546	if (family == PF_INET6)
1547		kernel_setsockopt(sock, SOL_IPV6, IPV6_V6ONLY,
1548					(char *)&val, sizeof(val));
1549
1550	if (type == SOCK_STREAM)
1551		sock->sk->sk_reuse = SK_CAN_REUSE; /* allow address reuse */
1552	error = kernel_bind(sock, sin, len);
1553	if (error < 0)
1554		goto bummer;
1555
1556	newlen = len;
1557	error = kernel_getsockname(sock, newsin, &newlen);
1558	if (error < 0)
1559		goto bummer;
1560
1561	if (protocol == IPPROTO_TCP) {
1562		if ((error = kernel_listen(sock, 64)) < 0)
1563			goto bummer;
1564	}
1565
1566	if ((svsk = svc_setup_socket(serv, sock, &error, flags)) != NULL) {
1567		svc_xprt_set_local(&svsk->sk_xprt, newsin, newlen);
1568		return (struct svc_xprt *)svsk;
1569	}
1570
1571bummer:
1572	dprintk("svc: svc_create_socket error = %d\n", -error);
1573	sock_release(sock);
1574	return ERR_PTR(error);
1575}
1576
1577/*
1578 * Detach the svc_sock from the socket so that no
1579 * more callbacks occur.
1580 */
1581static void svc_sock_detach(struct svc_xprt *xprt)
1582{
1583	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1584	struct sock *sk = svsk->sk_sk;
1585	wait_queue_head_t *wq;
1586
1587	dprintk("svc: svc_sock_detach(%p)\n", svsk);
1588
1589	/* put back the old socket callbacks */
1590	sk->sk_state_change = svsk->sk_ostate;
1591	sk->sk_data_ready = svsk->sk_odata;
1592	sk->sk_write_space = svsk->sk_owspace;
1593
1594	wq = sk_sleep(sk);
1595	if (wq && waitqueue_active(wq))
1596		wake_up_interruptible(wq);
1597}
1598
1599/*
1600 * Disconnect the socket, and reset the callbacks
1601 */
1602static void svc_tcp_sock_detach(struct svc_xprt *xprt)
1603{
1604	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1605
1606	dprintk("svc: svc_tcp_sock_detach(%p)\n", svsk);
1607
1608	svc_sock_detach(xprt);
1609
1610	if (!test_bit(XPT_LISTENER, &xprt->xpt_flags)) {
1611		svc_tcp_clear_pages(svsk);
1612		kernel_sock_shutdown(svsk->sk_sock, SHUT_RDWR);
1613	}
1614}
1615
1616/*
1617 * Free the svc_sock's socket resources and the svc_sock itself.
1618 */
1619static void svc_sock_free(struct svc_xprt *xprt)
1620{
1621	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1622	dprintk("svc: svc_sock_free(%p)\n", svsk);
1623
1624	if (svsk->sk_sock->file)
1625		sockfd_put(svsk->sk_sock);
1626	else
1627		sock_release(svsk->sk_sock);
1628	kfree(svsk);
1629}
1630
1631#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1632/*
1633 * Create a back channel svc_xprt which shares the fore channel socket.
1634 */
1635static struct svc_xprt *svc_bc_create_socket(struct svc_serv *serv,
1636					     int protocol,
1637					     struct net *net,
1638					     struct sockaddr *sin, int len,
1639					     int flags)
1640{
1641	struct svc_sock *svsk;
1642	struct svc_xprt *xprt;
1643
1644	if (protocol != IPPROTO_TCP) {
1645		printk(KERN_WARNING "svc: only TCP sockets"
1646			" supported on shared back channel\n");
1647		return ERR_PTR(-EINVAL);
1648	}
1649
1650	svsk = kzalloc(sizeof(*svsk), GFP_KERNEL);
1651	if (!svsk)
1652		return ERR_PTR(-ENOMEM);
1653
1654	xprt = &svsk->sk_xprt;
1655	svc_xprt_init(net, &svc_tcp_bc_class, xprt, serv);
1656
1657	serv->sv_bc_xprt = xprt;
1658
1659	return xprt;
1660}
1661
1662/*
1663 * Free a back channel svc_sock.
1664 */
1665static void svc_bc_sock_free(struct svc_xprt *xprt)
1666{
1667	if (xprt)
1668		kfree(container_of(xprt, struct svc_sock, sk_xprt));
1669}
1670#endif /* CONFIG_SUNRPC_BACKCHANNEL */