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   1/*
   2 * linux/net/sunrpc/xprtsock.c
   3 *
   4 * Client-side transport implementation for sockets.
   5 *
   6 * TCP callback races fixes (C) 1998 Red Hat
   7 * TCP send fixes (C) 1998 Red Hat
   8 * TCP NFS related read + write fixes
   9 *  (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
  10 *
  11 * Rewrite of larges part of the code in order to stabilize TCP stuff.
  12 * Fix behaviour when socket buffer is full.
  13 *  (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no>
  14 *
  15 * IP socket transport implementation, (C) 2005 Chuck Lever <cel@netapp.com>
  16 *
  17 * IPv6 support contributed by Gilles Quillard, Bull Open Source, 2005.
  18 *   <gilles.quillard@bull.net>
  19 */
  20
  21#include <linux/types.h>
  22#include <linux/string.h>
  23#include <linux/slab.h>
  24#include <linux/module.h>
  25#include <linux/capability.h>
  26#include <linux/pagemap.h>
  27#include <linux/errno.h>
  28#include <linux/socket.h>
  29#include <linux/in.h>
  30#include <linux/net.h>
  31#include <linux/mm.h>
  32#include <linux/un.h>
  33#include <linux/udp.h>
  34#include <linux/tcp.h>
  35#include <linux/sunrpc/clnt.h>
  36#include <linux/sunrpc/sched.h>
  37#include <linux/sunrpc/svcsock.h>
  38#include <linux/sunrpc/xprtsock.h>
  39#include <linux/file.h>
  40#ifdef CONFIG_SUNRPC_BACKCHANNEL
  41#include <linux/sunrpc/bc_xprt.h>
  42#endif
  43
  44#include <net/sock.h>
  45#include <net/checksum.h>
  46#include <net/udp.h>
  47#include <net/tcp.h>
  48
  49#include "sunrpc.h"
  50
  51static void xs_close(struct rpc_xprt *xprt);
  52
  53/*
  54 * xprtsock tunables
  55 */
  56static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  57static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
  58static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
  59
  60static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
  61static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
  62
  63#define XS_TCP_LINGER_TO	(15U * HZ)
  64static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
  65
  66/*
  67 * We can register our own files under /proc/sys/sunrpc by
  68 * calling register_sysctl_table() again.  The files in that
  69 * directory become the union of all files registered there.
  70 *
  71 * We simply need to make sure that we don't collide with
  72 * someone else's file names!
  73 */
  74
  75#ifdef RPC_DEBUG
  76
  77static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
  78static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
  79static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
  80static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
  81static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
  82
  83static struct ctl_table_header *sunrpc_table_header;
  84
  85/*
  86 * FIXME: changing the UDP slot table size should also resize the UDP
  87 *        socket buffers for existing UDP transports
  88 */
  89static ctl_table xs_tunables_table[] = {
  90	{
  91		.procname	= "udp_slot_table_entries",
  92		.data		= &xprt_udp_slot_table_entries,
  93		.maxlen		= sizeof(unsigned int),
  94		.mode		= 0644,
  95		.proc_handler	= proc_dointvec_minmax,
  96		.extra1		= &min_slot_table_size,
  97		.extra2		= &max_slot_table_size
  98	},
  99	{
 100		.procname	= "tcp_slot_table_entries",
 101		.data		= &xprt_tcp_slot_table_entries,
 102		.maxlen		= sizeof(unsigned int),
 103		.mode		= 0644,
 104		.proc_handler	= proc_dointvec_minmax,
 105		.extra1		= &min_slot_table_size,
 106		.extra2		= &max_slot_table_size
 107	},
 108	{
 109		.procname	= "tcp_max_slot_table_entries",
 110		.data		= &xprt_max_tcp_slot_table_entries,
 111		.maxlen		= sizeof(unsigned int),
 112		.mode		= 0644,
 113		.proc_handler	= proc_dointvec_minmax,
 114		.extra1		= &min_slot_table_size,
 115		.extra2		= &max_tcp_slot_table_limit
 116	},
 117	{
 118		.procname	= "min_resvport",
 119		.data		= &xprt_min_resvport,
 120		.maxlen		= sizeof(unsigned int),
 121		.mode		= 0644,
 122		.proc_handler	= proc_dointvec_minmax,
 123		.extra1		= &xprt_min_resvport_limit,
 124		.extra2		= &xprt_max_resvport_limit
 125	},
 126	{
 127		.procname	= "max_resvport",
 128		.data		= &xprt_max_resvport,
 129		.maxlen		= sizeof(unsigned int),
 130		.mode		= 0644,
 131		.proc_handler	= proc_dointvec_minmax,
 132		.extra1		= &xprt_min_resvport_limit,
 133		.extra2		= &xprt_max_resvport_limit
 134	},
 135	{
 136		.procname	= "tcp_fin_timeout",
 137		.data		= &xs_tcp_fin_timeout,
 138		.maxlen		= sizeof(xs_tcp_fin_timeout),
 139		.mode		= 0644,
 140		.proc_handler	= proc_dointvec_jiffies,
 141	},
 142	{ },
 143};
 144
 145static ctl_table sunrpc_table[] = {
 146	{
 147		.procname	= "sunrpc",
 148		.mode		= 0555,
 149		.child		= xs_tunables_table
 150	},
 151	{ },
 152};
 153
 154#endif
 155
 156/*
 157 * Wait duration for a reply from the RPC portmapper.
 158 */
 159#define XS_BIND_TO		(60U * HZ)
 160
 161/*
 162 * Delay if a UDP socket connect error occurs.  This is most likely some
 163 * kind of resource problem on the local host.
 164 */
 165#define XS_UDP_REEST_TO		(2U * HZ)
 166
 167/*
 168 * The reestablish timeout allows clients to delay for a bit before attempting
 169 * to reconnect to a server that just dropped our connection.
 170 *
 171 * We implement an exponential backoff when trying to reestablish a TCP
 172 * transport connection with the server.  Some servers like to drop a TCP
 173 * connection when they are overworked, so we start with a short timeout and
 174 * increase over time if the server is down or not responding.
 175 */
 176#define XS_TCP_INIT_REEST_TO	(3U * HZ)
 177#define XS_TCP_MAX_REEST_TO	(5U * 60 * HZ)
 178
 179/*
 180 * TCP idle timeout; client drops the transport socket if it is idle
 181 * for this long.  Note that we also timeout UDP sockets to prevent
 182 * holding port numbers when there is no RPC traffic.
 183 */
 184#define XS_IDLE_DISC_TO		(5U * 60 * HZ)
 185
 186#ifdef RPC_DEBUG
 187# undef  RPC_DEBUG_DATA
 188# define RPCDBG_FACILITY	RPCDBG_TRANS
 189#endif
 190
 191#ifdef RPC_DEBUG_DATA
 192static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 193{
 194	u8 *buf = (u8 *) packet;
 195	int j;
 196
 197	dprintk("RPC:       %s\n", msg);
 198	for (j = 0; j < count && j < 128; j += 4) {
 199		if (!(j & 31)) {
 200			if (j)
 201				dprintk("\n");
 202			dprintk("0x%04x ", j);
 203		}
 204		dprintk("%02x%02x%02x%02x ",
 205			buf[j], buf[j+1], buf[j+2], buf[j+3]);
 206	}
 207	dprintk("\n");
 208}
 209#else
 210static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 211{
 212	/* NOP */
 213}
 214#endif
 215
 216struct sock_xprt {
 217	struct rpc_xprt		xprt;
 218
 219	/*
 220	 * Network layer
 221	 */
 222	struct socket *		sock;
 223	struct sock *		inet;
 224
 225	/*
 226	 * State of TCP reply receive
 227	 */
 228	__be32			tcp_fraghdr,
 229				tcp_xid,
 230				tcp_calldir;
 231
 232	u32			tcp_offset,
 233				tcp_reclen;
 234
 235	unsigned long		tcp_copied,
 236				tcp_flags;
 237
 238	/*
 239	 * Connection of transports
 240	 */
 241	struct delayed_work	connect_worker;
 242	struct sockaddr_storage	srcaddr;
 243	unsigned short		srcport;
 244
 245	/*
 246	 * UDP socket buffer size parameters
 247	 */
 248	size_t			rcvsize,
 249				sndsize;
 250
 251	/*
 252	 * Saved socket callback addresses
 253	 */
 254	void			(*old_data_ready)(struct sock *, int);
 255	void			(*old_state_change)(struct sock *);
 256	void			(*old_write_space)(struct sock *);
 257	void			(*old_error_report)(struct sock *);
 258};
 259
 260/*
 261 * TCP receive state flags
 262 */
 263#define TCP_RCV_LAST_FRAG	(1UL << 0)
 264#define TCP_RCV_COPY_FRAGHDR	(1UL << 1)
 265#define TCP_RCV_COPY_XID	(1UL << 2)
 266#define TCP_RCV_COPY_DATA	(1UL << 3)
 267#define TCP_RCV_READ_CALLDIR	(1UL << 4)
 268#define TCP_RCV_COPY_CALLDIR	(1UL << 5)
 269
 270/*
 271 * TCP RPC flags
 272 */
 273#define TCP_RPC_REPLY		(1UL << 6)
 274
 275static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
 276{
 277	return (struct sockaddr *) &xprt->addr;
 278}
 279
 280static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
 281{
 282	return (struct sockaddr_un *) &xprt->addr;
 283}
 284
 285static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
 286{
 287	return (struct sockaddr_in *) &xprt->addr;
 288}
 289
 290static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
 291{
 292	return (struct sockaddr_in6 *) &xprt->addr;
 293}
 294
 295static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
 296{
 297	struct sockaddr *sap = xs_addr(xprt);
 298	struct sockaddr_in6 *sin6;
 299	struct sockaddr_in *sin;
 300	struct sockaddr_un *sun;
 301	char buf[128];
 302
 303	switch (sap->sa_family) {
 304	case AF_LOCAL:
 305		sun = xs_addr_un(xprt);
 306		strlcpy(buf, sun->sun_path, sizeof(buf));
 307		xprt->address_strings[RPC_DISPLAY_ADDR] =
 308						kstrdup(buf, GFP_KERNEL);
 309		break;
 310	case AF_INET:
 311		(void)rpc_ntop(sap, buf, sizeof(buf));
 312		xprt->address_strings[RPC_DISPLAY_ADDR] =
 313						kstrdup(buf, GFP_KERNEL);
 314		sin = xs_addr_in(xprt);
 315		snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
 316		break;
 317	case AF_INET6:
 318		(void)rpc_ntop(sap, buf, sizeof(buf));
 319		xprt->address_strings[RPC_DISPLAY_ADDR] =
 320						kstrdup(buf, GFP_KERNEL);
 321		sin6 = xs_addr_in6(xprt);
 322		snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
 323		break;
 324	default:
 325		BUG();
 326	}
 327
 328	xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
 329}
 330
 331static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
 332{
 333	struct sockaddr *sap = xs_addr(xprt);
 334	char buf[128];
 335
 336	snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
 337	xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
 338
 339	snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
 340	xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
 341}
 342
 343static void xs_format_peer_addresses(struct rpc_xprt *xprt,
 344				     const char *protocol,
 345				     const char *netid)
 346{
 347	xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
 348	xprt->address_strings[RPC_DISPLAY_NETID] = netid;
 349	xs_format_common_peer_addresses(xprt);
 350	xs_format_common_peer_ports(xprt);
 351}
 352
 353static void xs_update_peer_port(struct rpc_xprt *xprt)
 354{
 355	kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
 356	kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
 357
 358	xs_format_common_peer_ports(xprt);
 359}
 360
 361static void xs_free_peer_addresses(struct rpc_xprt *xprt)
 362{
 363	unsigned int i;
 364
 365	for (i = 0; i < RPC_DISPLAY_MAX; i++)
 366		switch (i) {
 367		case RPC_DISPLAY_PROTO:
 368		case RPC_DISPLAY_NETID:
 369			continue;
 370		default:
 371			kfree(xprt->address_strings[i]);
 372		}
 373}
 374
 375#define XS_SENDMSG_FLAGS	(MSG_DONTWAIT | MSG_NOSIGNAL)
 376
 377static int xs_send_kvec(struct socket *sock, struct sockaddr *addr, int addrlen, struct kvec *vec, unsigned int base, int more)
 378{
 379	struct msghdr msg = {
 380		.msg_name	= addr,
 381		.msg_namelen	= addrlen,
 382		.msg_flags	= XS_SENDMSG_FLAGS | (more ? MSG_MORE : 0),
 383	};
 384	struct kvec iov = {
 385		.iov_base	= vec->iov_base + base,
 386		.iov_len	= vec->iov_len - base,
 387	};
 388
 389	if (iov.iov_len != 0)
 390		return kernel_sendmsg(sock, &msg, &iov, 1, iov.iov_len);
 391	return kernel_sendmsg(sock, &msg, NULL, 0, 0);
 392}
 393
 394static int xs_send_pagedata(struct socket *sock, struct xdr_buf *xdr, unsigned int base, int more)
 395{
 396	struct page **ppage;
 397	unsigned int remainder;
 398	int err, sent = 0;
 399
 400	remainder = xdr->page_len - base;
 401	base += xdr->page_base;
 402	ppage = xdr->pages + (base >> PAGE_SHIFT);
 403	base &= ~PAGE_MASK;
 404	for(;;) {
 405		unsigned int len = min_t(unsigned int, PAGE_SIZE - base, remainder);
 406		int flags = XS_SENDMSG_FLAGS;
 407
 408		remainder -= len;
 409		if (remainder != 0 || more)
 410			flags |= MSG_MORE;
 411		err = sock->ops->sendpage(sock, *ppage, base, len, flags);
 412		if (remainder == 0 || err != len)
 413			break;
 414		sent += err;
 415		ppage++;
 416		base = 0;
 417	}
 418	if (sent == 0)
 419		return err;
 420	if (err > 0)
 421		sent += err;
 422	return sent;
 423}
 424
 425/**
 426 * xs_sendpages - write pages directly to a socket
 427 * @sock: socket to send on
 428 * @addr: UDP only -- address of destination
 429 * @addrlen: UDP only -- length of destination address
 430 * @xdr: buffer containing this request
 431 * @base: starting position in the buffer
 432 *
 433 */
 434static int xs_sendpages(struct socket *sock, struct sockaddr *addr, int addrlen, struct xdr_buf *xdr, unsigned int base)
 435{
 436	unsigned int remainder = xdr->len - base;
 437	int err, sent = 0;
 438
 439	if (unlikely(!sock))
 440		return -ENOTSOCK;
 441
 442	clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags);
 443	if (base != 0) {
 444		addr = NULL;
 445		addrlen = 0;
 446	}
 447
 448	if (base < xdr->head[0].iov_len || addr != NULL) {
 449		unsigned int len = xdr->head[0].iov_len - base;
 450		remainder -= len;
 451		err = xs_send_kvec(sock, addr, addrlen, &xdr->head[0], base, remainder != 0);
 452		if (remainder == 0 || err != len)
 453			goto out;
 454		sent += err;
 455		base = 0;
 456	} else
 457		base -= xdr->head[0].iov_len;
 458
 459	if (base < xdr->page_len) {
 460		unsigned int len = xdr->page_len - base;
 461		remainder -= len;
 462		err = xs_send_pagedata(sock, xdr, base, remainder != 0);
 463		if (remainder == 0 || err != len)
 464			goto out;
 465		sent += err;
 466		base = 0;
 467	} else
 468		base -= xdr->page_len;
 469
 470	if (base >= xdr->tail[0].iov_len)
 471		return sent;
 472	err = xs_send_kvec(sock, NULL, 0, &xdr->tail[0], base, 0);
 473out:
 474	if (sent == 0)
 475		return err;
 476	if (err > 0)
 477		sent += err;
 478	return sent;
 479}
 480
 481static void xs_nospace_callback(struct rpc_task *task)
 482{
 483	struct sock_xprt *transport = container_of(task->tk_rqstp->rq_xprt, struct sock_xprt, xprt);
 484
 485	transport->inet->sk_write_pending--;
 486	clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 487}
 488
 489/**
 490 * xs_nospace - place task on wait queue if transmit was incomplete
 491 * @task: task to put to sleep
 492 *
 493 */
 494static int xs_nospace(struct rpc_task *task)
 495{
 496	struct rpc_rqst *req = task->tk_rqstp;
 497	struct rpc_xprt *xprt = req->rq_xprt;
 498	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 499	int ret = -EAGAIN;
 500
 501	dprintk("RPC: %5u xmit incomplete (%u left of %u)\n",
 502			task->tk_pid, req->rq_slen - req->rq_bytes_sent,
 503			req->rq_slen);
 504
 505	/* Protect against races with write_space */
 506	spin_lock_bh(&xprt->transport_lock);
 507
 508	/* Don't race with disconnect */
 509	if (xprt_connected(xprt)) {
 510		if (test_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags)) {
 511			/*
 512			 * Notify TCP that we're limited by the application
 513			 * window size
 514			 */
 515			set_bit(SOCK_NOSPACE, &transport->sock->flags);
 516			transport->inet->sk_write_pending++;
 517			/* ...and wait for more buffer space */
 518			xprt_wait_for_buffer_space(task, xs_nospace_callback);
 519		}
 520	} else {
 521		clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 522		ret = -ENOTCONN;
 523	}
 524
 525	spin_unlock_bh(&xprt->transport_lock);
 526	return ret;
 527}
 528
 529/*
 530 * Construct a stream transport record marker in @buf.
 531 */
 532static inline void xs_encode_stream_record_marker(struct xdr_buf *buf)
 533{
 534	u32 reclen = buf->len - sizeof(rpc_fraghdr);
 535	rpc_fraghdr *base = buf->head[0].iov_base;
 536	*base = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | reclen);
 537}
 538
 539/**
 540 * xs_local_send_request - write an RPC request to an AF_LOCAL socket
 541 * @task: RPC task that manages the state of an RPC request
 542 *
 543 * Return values:
 544 *        0:	The request has been sent
 545 *   EAGAIN:	The socket was blocked, please call again later to
 546 *		complete the request
 547 * ENOTCONN:	Caller needs to invoke connect logic then call again
 548 *    other:	Some other error occured, the request was not sent
 549 */
 550static int xs_local_send_request(struct rpc_task *task)
 551{
 552	struct rpc_rqst *req = task->tk_rqstp;
 553	struct rpc_xprt *xprt = req->rq_xprt;
 554	struct sock_xprt *transport =
 555				container_of(xprt, struct sock_xprt, xprt);
 556	struct xdr_buf *xdr = &req->rq_snd_buf;
 557	int status;
 558
 559	xs_encode_stream_record_marker(&req->rq_snd_buf);
 560
 561	xs_pktdump("packet data:",
 562			req->rq_svec->iov_base, req->rq_svec->iov_len);
 563
 564	status = xs_sendpages(transport->sock, NULL, 0,
 565						xdr, req->rq_bytes_sent);
 566	dprintk("RPC:       %s(%u) = %d\n",
 567			__func__, xdr->len - req->rq_bytes_sent, status);
 568	if (likely(status >= 0)) {
 569		req->rq_bytes_sent += status;
 570		req->rq_xmit_bytes_sent += status;
 571		if (likely(req->rq_bytes_sent >= req->rq_slen)) {
 572			req->rq_bytes_sent = 0;
 573			return 0;
 574		}
 575		status = -EAGAIN;
 576	}
 577
 578	switch (status) {
 579	case -EAGAIN:
 580		status = xs_nospace(task);
 581		break;
 582	default:
 583		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 584			-status);
 585	case -EPIPE:
 586		xs_close(xprt);
 587		status = -ENOTCONN;
 588	}
 589
 590	return status;
 591}
 592
 593/**
 594 * xs_udp_send_request - write an RPC request to a UDP socket
 595 * @task: address of RPC task that manages the state of an RPC request
 596 *
 597 * Return values:
 598 *        0:	The request has been sent
 599 *   EAGAIN:	The socket was blocked, please call again later to
 600 *		complete the request
 601 * ENOTCONN:	Caller needs to invoke connect logic then call again
 602 *    other:	Some other error occurred, the request was not sent
 603 */
 604static int xs_udp_send_request(struct rpc_task *task)
 605{
 606	struct rpc_rqst *req = task->tk_rqstp;
 607	struct rpc_xprt *xprt = req->rq_xprt;
 608	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 609	struct xdr_buf *xdr = &req->rq_snd_buf;
 610	int status;
 611
 612	xs_pktdump("packet data:",
 613				req->rq_svec->iov_base,
 614				req->rq_svec->iov_len);
 615
 616	if (!xprt_bound(xprt))
 617		return -ENOTCONN;
 618	status = xs_sendpages(transport->sock,
 619			      xs_addr(xprt),
 620			      xprt->addrlen, xdr,
 621			      req->rq_bytes_sent);
 622
 623	dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
 624			xdr->len - req->rq_bytes_sent, status);
 625
 626	if (status >= 0) {
 627		req->rq_xmit_bytes_sent += status;
 628		if (status >= req->rq_slen)
 629			return 0;
 630		/* Still some bytes left; set up for a retry later. */
 631		status = -EAGAIN;
 632	}
 633
 634	switch (status) {
 635	case -ENOTSOCK:
 636		status = -ENOTCONN;
 637		/* Should we call xs_close() here? */
 638		break;
 639	case -EAGAIN:
 640		status = xs_nospace(task);
 641		break;
 642	default:
 643		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 644			-status);
 645	case -ENETUNREACH:
 646	case -EPIPE:
 647	case -ECONNREFUSED:
 648		/* When the server has died, an ICMP port unreachable message
 649		 * prompts ECONNREFUSED. */
 650		clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 651	}
 652
 653	return status;
 654}
 655
 656/**
 657 * xs_tcp_shutdown - gracefully shut down a TCP socket
 658 * @xprt: transport
 659 *
 660 * Initiates a graceful shutdown of the TCP socket by calling the
 661 * equivalent of shutdown(SHUT_WR);
 662 */
 663static void xs_tcp_shutdown(struct rpc_xprt *xprt)
 664{
 665	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 666	struct socket *sock = transport->sock;
 667
 668	if (sock != NULL)
 669		kernel_sock_shutdown(sock, SHUT_WR);
 670}
 671
 672/**
 673 * xs_tcp_send_request - write an RPC request to a TCP socket
 674 * @task: address of RPC task that manages the state of an RPC request
 675 *
 676 * Return values:
 677 *        0:	The request has been sent
 678 *   EAGAIN:	The socket was blocked, please call again later to
 679 *		complete the request
 680 * ENOTCONN:	Caller needs to invoke connect logic then call again
 681 *    other:	Some other error occurred, the request was not sent
 682 *
 683 * XXX: In the case of soft timeouts, should we eventually give up
 684 *	if sendmsg is not able to make progress?
 685 */
 686static int xs_tcp_send_request(struct rpc_task *task)
 687{
 688	struct rpc_rqst *req = task->tk_rqstp;
 689	struct rpc_xprt *xprt = req->rq_xprt;
 690	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 691	struct xdr_buf *xdr = &req->rq_snd_buf;
 692	int status;
 693
 694	xs_encode_stream_record_marker(&req->rq_snd_buf);
 695
 696	xs_pktdump("packet data:",
 697				req->rq_svec->iov_base,
 698				req->rq_svec->iov_len);
 699
 700	/* Continue transmitting the packet/record. We must be careful
 701	 * to cope with writespace callbacks arriving _after_ we have
 702	 * called sendmsg(). */
 703	while (1) {
 704		status = xs_sendpages(transport->sock,
 705					NULL, 0, xdr, req->rq_bytes_sent);
 706
 707		dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
 708				xdr->len - req->rq_bytes_sent, status);
 709
 710		if (unlikely(status < 0))
 711			break;
 712
 713		/* If we've sent the entire packet, immediately
 714		 * reset the count of bytes sent. */
 715		req->rq_bytes_sent += status;
 716		req->rq_xmit_bytes_sent += status;
 717		if (likely(req->rq_bytes_sent >= req->rq_slen)) {
 718			req->rq_bytes_sent = 0;
 719			return 0;
 720		}
 721
 722		if (status != 0)
 723			continue;
 724		status = -EAGAIN;
 725		break;
 726	}
 727
 728	switch (status) {
 729	case -ENOTSOCK:
 730		status = -ENOTCONN;
 731		/* Should we call xs_close() here? */
 732		break;
 733	case -EAGAIN:
 734		status = xs_nospace(task);
 735		break;
 736	default:
 737		dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 738			-status);
 739	case -ECONNRESET:
 740	case -EPIPE:
 741		xs_tcp_shutdown(xprt);
 742	case -ECONNREFUSED:
 743	case -ENOTCONN:
 744		clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 745	}
 746
 747	return status;
 748}
 749
 750/**
 751 * xs_tcp_release_xprt - clean up after a tcp transmission
 752 * @xprt: transport
 753 * @task: rpc task
 754 *
 755 * This cleans up if an error causes us to abort the transmission of a request.
 756 * In this case, the socket may need to be reset in order to avoid confusing
 757 * the server.
 758 */
 759static void xs_tcp_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task)
 760{
 761	struct rpc_rqst *req;
 762
 763	if (task != xprt->snd_task)
 764		return;
 765	if (task == NULL)
 766		goto out_release;
 767	req = task->tk_rqstp;
 768	if (req == NULL)
 769		goto out_release;
 770	if (req->rq_bytes_sent == 0)
 771		goto out_release;
 772	if (req->rq_bytes_sent == req->rq_snd_buf.len)
 773		goto out_release;
 774	set_bit(XPRT_CLOSE_WAIT, &task->tk_xprt->state);
 775out_release:
 776	xprt_release_xprt(xprt, task);
 777}
 778
 779static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
 780{
 781	transport->old_data_ready = sk->sk_data_ready;
 782	transport->old_state_change = sk->sk_state_change;
 783	transport->old_write_space = sk->sk_write_space;
 784	transport->old_error_report = sk->sk_error_report;
 785}
 786
 787static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
 788{
 789	sk->sk_data_ready = transport->old_data_ready;
 790	sk->sk_state_change = transport->old_state_change;
 791	sk->sk_write_space = transport->old_write_space;
 792	sk->sk_error_report = transport->old_error_report;
 793}
 794
 795static void xs_reset_transport(struct sock_xprt *transport)
 796{
 797	struct socket *sock = transport->sock;
 798	struct sock *sk = transport->inet;
 799
 800	if (sk == NULL)
 801		return;
 802
 803	transport->srcport = 0;
 804
 805	write_lock_bh(&sk->sk_callback_lock);
 806	transport->inet = NULL;
 807	transport->sock = NULL;
 808
 809	sk->sk_user_data = NULL;
 810
 811	xs_restore_old_callbacks(transport, sk);
 812	write_unlock_bh(&sk->sk_callback_lock);
 813
 814	sk->sk_no_check = 0;
 815
 816	sock_release(sock);
 817}
 818
 819/**
 820 * xs_close - close a socket
 821 * @xprt: transport
 822 *
 823 * This is used when all requests are complete; ie, no DRC state remains
 824 * on the server we want to save.
 825 *
 826 * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
 827 * xs_reset_transport() zeroing the socket from underneath a writer.
 828 */
 829static void xs_close(struct rpc_xprt *xprt)
 830{
 831	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 832
 833	dprintk("RPC:       xs_close xprt %p\n", xprt);
 834
 835	xs_reset_transport(transport);
 836	xprt->reestablish_timeout = 0;
 837
 838	smp_mb__before_clear_bit();
 839	clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
 840	clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
 841	clear_bit(XPRT_CLOSING, &xprt->state);
 842	smp_mb__after_clear_bit();
 843	xprt_disconnect_done(xprt);
 844}
 845
 846static void xs_tcp_close(struct rpc_xprt *xprt)
 847{
 848	if (test_and_clear_bit(XPRT_CONNECTION_CLOSE, &xprt->state))
 849		xs_close(xprt);
 850	else
 851		xs_tcp_shutdown(xprt);
 852}
 853
 854/**
 855 * xs_destroy - prepare to shutdown a transport
 856 * @xprt: doomed transport
 857 *
 858 */
 859static void xs_destroy(struct rpc_xprt *xprt)
 860{
 861	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 862
 863	dprintk("RPC:       xs_destroy xprt %p\n", xprt);
 864
 865	cancel_delayed_work_sync(&transport->connect_worker);
 866
 867	xs_close(xprt);
 868	xs_free_peer_addresses(xprt);
 869	xprt_free(xprt);
 870	module_put(THIS_MODULE);
 871}
 872
 873static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
 874{
 875	return (struct rpc_xprt *) sk->sk_user_data;
 876}
 877
 878static int xs_local_copy_to_xdr(struct xdr_buf *xdr, struct sk_buff *skb)
 879{
 880	struct xdr_skb_reader desc = {
 881		.skb		= skb,
 882		.offset		= sizeof(rpc_fraghdr),
 883		.count		= skb->len - sizeof(rpc_fraghdr),
 884	};
 885
 886	if (xdr_partial_copy_from_skb(xdr, 0, &desc, xdr_skb_read_bits) < 0)
 887		return -1;
 888	if (desc.count)
 889		return -1;
 890	return 0;
 891}
 892
 893/**
 894 * xs_local_data_ready - "data ready" callback for AF_LOCAL sockets
 895 * @sk: socket with data to read
 896 * @len: how much data to read
 897 *
 898 * Currently this assumes we can read the whole reply in a single gulp.
 899 */
 900static void xs_local_data_ready(struct sock *sk, int len)
 901{
 902	struct rpc_task *task;
 903	struct rpc_xprt *xprt;
 904	struct rpc_rqst *rovr;
 905	struct sk_buff *skb;
 906	int err, repsize, copied;
 907	u32 _xid;
 908	__be32 *xp;
 909
 910	read_lock_bh(&sk->sk_callback_lock);
 911	dprintk("RPC:       %s...\n", __func__);
 912	xprt = xprt_from_sock(sk);
 913	if (xprt == NULL)
 914		goto out;
 915
 916	skb = skb_recv_datagram(sk, 0, 1, &err);
 917	if (skb == NULL)
 918		goto out;
 919
 920	if (xprt->shutdown)
 921		goto dropit;
 922
 923	repsize = skb->len - sizeof(rpc_fraghdr);
 924	if (repsize < 4) {
 925		dprintk("RPC:       impossible RPC reply size %d\n", repsize);
 926		goto dropit;
 927	}
 928
 929	/* Copy the XID from the skb... */
 930	xp = skb_header_pointer(skb, sizeof(rpc_fraghdr), sizeof(_xid), &_xid);
 931	if (xp == NULL)
 932		goto dropit;
 933
 934	/* Look up and lock the request corresponding to the given XID */
 935	spin_lock(&xprt->transport_lock);
 936	rovr = xprt_lookup_rqst(xprt, *xp);
 937	if (!rovr)
 938		goto out_unlock;
 939	task = rovr->rq_task;
 940
 941	copied = rovr->rq_private_buf.buflen;
 942	if (copied > repsize)
 943		copied = repsize;
 944
 945	if (xs_local_copy_to_xdr(&rovr->rq_private_buf, skb)) {
 946		dprintk("RPC:       sk_buff copy failed\n");
 947		goto out_unlock;
 948	}
 949
 950	xprt_complete_rqst(task, copied);
 951
 952 out_unlock:
 953	spin_unlock(&xprt->transport_lock);
 954 dropit:
 955	skb_free_datagram(sk, skb);
 956 out:
 957	read_unlock_bh(&sk->sk_callback_lock);
 958}
 959
 960/**
 961 * xs_udp_data_ready - "data ready" callback for UDP sockets
 962 * @sk: socket with data to read
 963 * @len: how much data to read
 964 *
 965 */
 966static void xs_udp_data_ready(struct sock *sk, int len)
 967{
 968	struct rpc_task *task;
 969	struct rpc_xprt *xprt;
 970	struct rpc_rqst *rovr;
 971	struct sk_buff *skb;
 972	int err, repsize, copied;
 973	u32 _xid;
 974	__be32 *xp;
 975
 976	read_lock_bh(&sk->sk_callback_lock);
 977	dprintk("RPC:       xs_udp_data_ready...\n");
 978	if (!(xprt = xprt_from_sock(sk)))
 979		goto out;
 980
 981	if ((skb = skb_recv_datagram(sk, 0, 1, &err)) == NULL)
 982		goto out;
 983
 984	if (xprt->shutdown)
 985		goto dropit;
 986
 987	repsize = skb->len - sizeof(struct udphdr);
 988	if (repsize < 4) {
 989		dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
 990		goto dropit;
 991	}
 992
 993	/* Copy the XID from the skb... */
 994	xp = skb_header_pointer(skb, sizeof(struct udphdr),
 995				sizeof(_xid), &_xid);
 996	if (xp == NULL)
 997		goto dropit;
 998
 999	/* Look up and lock the request corresponding to the given XID */
1000	spin_lock(&xprt->transport_lock);
1001	rovr = xprt_lookup_rqst(xprt, *xp);
1002	if (!rovr)
1003		goto out_unlock;
1004	task = rovr->rq_task;
1005
1006	if ((copied = rovr->rq_private_buf.buflen) > repsize)
1007		copied = repsize;
1008
1009	/* Suck it into the iovec, verify checksum if not done by hw. */
1010	if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1011		UDPX_INC_STATS_BH(sk, UDP_MIB_INERRORS);
1012		goto out_unlock;
1013	}
1014
1015	UDPX_INC_STATS_BH(sk, UDP_MIB_INDATAGRAMS);
1016
1017	/* Something worked... */
1018	dst_confirm(skb_dst(skb));
1019
1020	xprt_adjust_cwnd(task, copied);
1021	xprt_complete_rqst(task, copied);
1022
1023 out_unlock:
1024	spin_unlock(&xprt->transport_lock);
1025 dropit:
1026	skb_free_datagram(sk, skb);
1027 out:
1028	read_unlock_bh(&sk->sk_callback_lock);
1029}
1030
1031static inline void xs_tcp_read_fraghdr(struct rpc_xprt *xprt, struct xdr_skb_reader *desc)
1032{
1033	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1034	size_t len, used;
1035	char *p;
1036
1037	p = ((char *) &transport->tcp_fraghdr) + transport->tcp_offset;
1038	len = sizeof(transport->tcp_fraghdr) - transport->tcp_offset;
1039	used = xdr_skb_read_bits(desc, p, len);
1040	transport->tcp_offset += used;
1041	if (used != len)
1042		return;
1043
1044	transport->tcp_reclen = ntohl(transport->tcp_fraghdr);
1045	if (transport->tcp_reclen & RPC_LAST_STREAM_FRAGMENT)
1046		transport->tcp_flags |= TCP_RCV_LAST_FRAG;
1047	else
1048		transport->tcp_flags &= ~TCP_RCV_LAST_FRAG;
1049	transport->tcp_reclen &= RPC_FRAGMENT_SIZE_MASK;
1050
1051	transport->tcp_flags &= ~TCP_RCV_COPY_FRAGHDR;
1052	transport->tcp_offset = 0;
1053
1054	/* Sanity check of the record length */
1055	if (unlikely(transport->tcp_reclen < 8)) {
1056		dprintk("RPC:       invalid TCP record fragment length\n");
1057		xprt_force_disconnect(xprt);
1058		return;
1059	}
1060	dprintk("RPC:       reading TCP record fragment of length %d\n",
1061			transport->tcp_reclen);
1062}
1063
1064static void xs_tcp_check_fraghdr(struct sock_xprt *transport)
1065{
1066	if (transport->tcp_offset == transport->tcp_reclen) {
1067		transport->tcp_flags |= TCP_RCV_COPY_FRAGHDR;
1068		transport->tcp_offset = 0;
1069		if (transport->tcp_flags & TCP_RCV_LAST_FRAG) {
1070			transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1071			transport->tcp_flags |= TCP_RCV_COPY_XID;
1072			transport->tcp_copied = 0;
1073		}
1074	}
1075}
1076
1077static inline void xs_tcp_read_xid(struct sock_xprt *transport, struct xdr_skb_reader *desc)
1078{
1079	size_t len, used;
1080	char *p;
1081
1082	len = sizeof(transport->tcp_xid) - transport->tcp_offset;
1083	dprintk("RPC:       reading XID (%Zu bytes)\n", len);
1084	p = ((char *) &transport->tcp_xid) + transport->tcp_offset;
1085	used = xdr_skb_read_bits(desc, p, len);
1086	transport->tcp_offset += used;
1087	if (used != len)
1088		return;
1089	transport->tcp_flags &= ~TCP_RCV_COPY_XID;
1090	transport->tcp_flags |= TCP_RCV_READ_CALLDIR;
1091	transport->tcp_copied = 4;
1092	dprintk("RPC:       reading %s XID %08x\n",
1093			(transport->tcp_flags & TCP_RPC_REPLY) ? "reply for"
1094							      : "request with",
1095			ntohl(transport->tcp_xid));
1096	xs_tcp_check_fraghdr(transport);
1097}
1098
1099static inline void xs_tcp_read_calldir(struct sock_xprt *transport,
1100				       struct xdr_skb_reader *desc)
1101{
1102	size_t len, used;
1103	u32 offset;
1104	char *p;
1105
1106	/*
1107	 * We want transport->tcp_offset to be 8 at the end of this routine
1108	 * (4 bytes for the xid and 4 bytes for the call/reply flag).
1109	 * When this function is called for the first time,
1110	 * transport->tcp_offset is 4 (after having already read the xid).
1111	 */
1112	offset = transport->tcp_offset - sizeof(transport->tcp_xid);
1113	len = sizeof(transport->tcp_calldir) - offset;
1114	dprintk("RPC:       reading CALL/REPLY flag (%Zu bytes)\n", len);
1115	p = ((char *) &transport->tcp_calldir) + offset;
1116	used = xdr_skb_read_bits(desc, p, len);
1117	transport->tcp_offset += used;
1118	if (used != len)
1119		return;
1120	transport->tcp_flags &= ~TCP_RCV_READ_CALLDIR;
1121	/*
1122	 * We don't yet have the XDR buffer, so we will write the calldir
1123	 * out after we get the buffer from the 'struct rpc_rqst'
1124	 */
1125	switch (ntohl(transport->tcp_calldir)) {
1126	case RPC_REPLY:
1127		transport->tcp_flags |= TCP_RCV_COPY_CALLDIR;
1128		transport->tcp_flags |= TCP_RCV_COPY_DATA;
1129		transport->tcp_flags |= TCP_RPC_REPLY;
1130		break;
1131	case RPC_CALL:
1132		transport->tcp_flags |= TCP_RCV_COPY_CALLDIR;
1133		transport->tcp_flags |= TCP_RCV_COPY_DATA;
1134		transport->tcp_flags &= ~TCP_RPC_REPLY;
1135		break;
1136	default:
1137		dprintk("RPC:       invalid request message type\n");
1138		xprt_force_disconnect(&transport->xprt);
1139	}
1140	xs_tcp_check_fraghdr(transport);
1141}
1142
1143static inline void xs_tcp_read_common(struct rpc_xprt *xprt,
1144				     struct xdr_skb_reader *desc,
1145				     struct rpc_rqst *req)
1146{
1147	struct sock_xprt *transport =
1148				container_of(xprt, struct sock_xprt, xprt);
1149	struct xdr_buf *rcvbuf;
1150	size_t len;
1151	ssize_t r;
1152
1153	rcvbuf = &req->rq_private_buf;
1154
1155	if (transport->tcp_flags & TCP_RCV_COPY_CALLDIR) {
1156		/*
1157		 * Save the RPC direction in the XDR buffer
1158		 */
1159		memcpy(rcvbuf->head[0].iov_base + transport->tcp_copied,
1160			&transport->tcp_calldir,
1161			sizeof(transport->tcp_calldir));
1162		transport->tcp_copied += sizeof(transport->tcp_calldir);
1163		transport->tcp_flags &= ~TCP_RCV_COPY_CALLDIR;
1164	}
1165
1166	len = desc->count;
1167	if (len > transport->tcp_reclen - transport->tcp_offset) {
1168		struct xdr_skb_reader my_desc;
1169
1170		len = transport->tcp_reclen - transport->tcp_offset;
1171		memcpy(&my_desc, desc, sizeof(my_desc));
1172		my_desc.count = len;
1173		r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied,
1174					  &my_desc, xdr_skb_read_bits);
1175		desc->count -= r;
1176		desc->offset += r;
1177	} else
1178		r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied,
1179					  desc, xdr_skb_read_bits);
1180
1181	if (r > 0) {
1182		transport->tcp_copied += r;
1183		transport->tcp_offset += r;
1184	}
1185	if (r != len) {
1186		/* Error when copying to the receive buffer,
1187		 * usually because we weren't able to allocate
1188		 * additional buffer pages. All we can do now
1189		 * is turn off TCP_RCV_COPY_DATA, so the request
1190		 * will not receive any additional updates,
1191		 * and time out.
1192		 * Any remaining data from this record will
1193		 * be discarded.
1194		 */
1195		transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1196		dprintk("RPC:       XID %08x truncated request\n",
1197				ntohl(transport->tcp_xid));
1198		dprintk("RPC:       xprt = %p, tcp_copied = %lu, "
1199				"tcp_offset = %u, tcp_reclen = %u\n",
1200				xprt, transport->tcp_copied,
1201				transport->tcp_offset, transport->tcp_reclen);
1202		return;
1203	}
1204
1205	dprintk("RPC:       XID %08x read %Zd bytes\n",
1206			ntohl(transport->tcp_xid), r);
1207	dprintk("RPC:       xprt = %p, tcp_copied = %lu, tcp_offset = %u, "
1208			"tcp_reclen = %u\n", xprt, transport->tcp_copied,
1209			transport->tcp_offset, transport->tcp_reclen);
1210
1211	if (transport->tcp_copied == req->rq_private_buf.buflen)
1212		transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1213	else if (transport->tcp_offset == transport->tcp_reclen) {
1214		if (transport->tcp_flags & TCP_RCV_LAST_FRAG)
1215			transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1216	}
1217}
1218
1219/*
1220 * Finds the request corresponding to the RPC xid and invokes the common
1221 * tcp read code to read the data.
1222 */
1223static inline int xs_tcp_read_reply(struct rpc_xprt *xprt,
1224				    struct xdr_skb_reader *desc)
1225{
1226	struct sock_xprt *transport =
1227				container_of(xprt, struct sock_xprt, xprt);
1228	struct rpc_rqst *req;
1229
1230	dprintk("RPC:       read reply XID %08x\n", ntohl(transport->tcp_xid));
1231
1232	/* Find and lock the request corresponding to this xid */
1233	spin_lock(&xprt->transport_lock);
1234	req = xprt_lookup_rqst(xprt, transport->tcp_xid);
1235	if (!req) {
1236		dprintk("RPC:       XID %08x request not found!\n",
1237				ntohl(transport->tcp_xid));
1238		spin_unlock(&xprt->transport_lock);
1239		return -1;
1240	}
1241
1242	xs_tcp_read_common(xprt, desc, req);
1243
1244	if (!(transport->tcp_flags & TCP_RCV_COPY_DATA))
1245		xprt_complete_rqst(req->rq_task, transport->tcp_copied);
1246
1247	spin_unlock(&xprt->transport_lock);
1248	return 0;
1249}
1250
1251#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1252/*
1253 * Obtains an rpc_rqst previously allocated and invokes the common
1254 * tcp read code to read the data.  The result is placed in the callback
1255 * queue.
1256 * If we're unable to obtain the rpc_rqst we schedule the closing of the
1257 * connection and return -1.
1258 */
1259static inline int xs_tcp_read_callback(struct rpc_xprt *xprt,
1260				       struct xdr_skb_reader *desc)
1261{
1262	struct sock_xprt *transport =
1263				container_of(xprt, struct sock_xprt, xprt);
1264	struct rpc_rqst *req;
1265
1266	req = xprt_alloc_bc_request(xprt);
1267	if (req == NULL) {
1268		printk(KERN_WARNING "Callback slot table overflowed\n");
1269		xprt_force_disconnect(xprt);
1270		return -1;
1271	}
1272
1273	req->rq_xid = transport->tcp_xid;
1274	dprintk("RPC:       read callback  XID %08x\n", ntohl(req->rq_xid));
1275	xs_tcp_read_common(xprt, desc, req);
1276
1277	if (!(transport->tcp_flags & TCP_RCV_COPY_DATA)) {
1278		struct svc_serv *bc_serv = xprt->bc_serv;
1279
1280		/*
1281		 * Add callback request to callback list.  The callback
1282		 * service sleeps on the sv_cb_waitq waiting for new
1283		 * requests.  Wake it up after adding enqueing the
1284		 * request.
1285		 */
1286		dprintk("RPC:       add callback request to list\n");
1287		spin_lock(&bc_serv->sv_cb_lock);
1288		list_add(&req->rq_bc_list, &bc_serv->sv_cb_list);
1289		spin_unlock(&bc_serv->sv_cb_lock);
1290		wake_up(&bc_serv->sv_cb_waitq);
1291	}
1292
1293	req->rq_private_buf.len = transport->tcp_copied;
1294
1295	return 0;
1296}
1297
1298static inline int _xs_tcp_read_data(struct rpc_xprt *xprt,
1299					struct xdr_skb_reader *desc)
1300{
1301	struct sock_xprt *transport =
1302				container_of(xprt, struct sock_xprt, xprt);
1303
1304	return (transport->tcp_flags & TCP_RPC_REPLY) ?
1305		xs_tcp_read_reply(xprt, desc) :
1306		xs_tcp_read_callback(xprt, desc);
1307}
1308#else
1309static inline int _xs_tcp_read_data(struct rpc_xprt *xprt,
1310					struct xdr_skb_reader *desc)
1311{
1312	return xs_tcp_read_reply(xprt, desc);
1313}
1314#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1315
1316/*
1317 * Read data off the transport.  This can be either an RPC_CALL or an
1318 * RPC_REPLY.  Relay the processing to helper functions.
1319 */
1320static void xs_tcp_read_data(struct rpc_xprt *xprt,
1321				    struct xdr_skb_reader *desc)
1322{
1323	struct sock_xprt *transport =
1324				container_of(xprt, struct sock_xprt, xprt);
1325
1326	if (_xs_tcp_read_data(xprt, desc) == 0)
1327		xs_tcp_check_fraghdr(transport);
1328	else {
1329		/*
1330		 * The transport_lock protects the request handling.
1331		 * There's no need to hold it to update the tcp_flags.
1332		 */
1333		transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1334	}
1335}
1336
1337static inline void xs_tcp_read_discard(struct sock_xprt *transport, struct xdr_skb_reader *desc)
1338{
1339	size_t len;
1340
1341	len = transport->tcp_reclen - transport->tcp_offset;
1342	if (len > desc->count)
1343		len = desc->count;
1344	desc->count -= len;
1345	desc->offset += len;
1346	transport->tcp_offset += len;
1347	dprintk("RPC:       discarded %Zu bytes\n", len);
1348	xs_tcp_check_fraghdr(transport);
1349}
1350
1351static int xs_tcp_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, unsigned int offset, size_t len)
1352{
1353	struct rpc_xprt *xprt = rd_desc->arg.data;
1354	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1355	struct xdr_skb_reader desc = {
1356		.skb	= skb,
1357		.offset	= offset,
1358		.count	= len,
1359	};
1360
1361	dprintk("RPC:       xs_tcp_data_recv started\n");
1362	do {
1363		/* Read in a new fragment marker if necessary */
1364		/* Can we ever really expect to get completely empty fragments? */
1365		if (transport->tcp_flags & TCP_RCV_COPY_FRAGHDR) {
1366			xs_tcp_read_fraghdr(xprt, &desc);
1367			continue;
1368		}
1369		/* Read in the xid if necessary */
1370		if (transport->tcp_flags & TCP_RCV_COPY_XID) {
1371			xs_tcp_read_xid(transport, &desc);
1372			continue;
1373		}
1374		/* Read in the call/reply flag */
1375		if (transport->tcp_flags & TCP_RCV_READ_CALLDIR) {
1376			xs_tcp_read_calldir(transport, &desc);
1377			continue;
1378		}
1379		/* Read in the request data */
1380		if (transport->tcp_flags & TCP_RCV_COPY_DATA) {
1381			xs_tcp_read_data(xprt, &desc);
1382			continue;
1383		}
1384		/* Skip over any trailing bytes on short reads */
1385		xs_tcp_read_discard(transport, &desc);
1386	} while (desc.count);
1387	dprintk("RPC:       xs_tcp_data_recv done\n");
1388	return len - desc.count;
1389}
1390
1391/**
1392 * xs_tcp_data_ready - "data ready" callback for TCP sockets
1393 * @sk: socket with data to read
1394 * @bytes: how much data to read
1395 *
1396 */
1397static void xs_tcp_data_ready(struct sock *sk, int bytes)
1398{
1399	struct rpc_xprt *xprt;
1400	read_descriptor_t rd_desc;
1401	int read;
1402
1403	dprintk("RPC:       xs_tcp_data_ready...\n");
1404
1405	read_lock_bh(&sk->sk_callback_lock);
1406	if (!(xprt = xprt_from_sock(sk)))
1407		goto out;
1408	if (xprt->shutdown)
1409		goto out;
1410
1411	/* Any data means we had a useful conversation, so
1412	 * the we don't need to delay the next reconnect
1413	 */
1414	if (xprt->reestablish_timeout)
1415		xprt->reestablish_timeout = 0;
1416
1417	/* We use rd_desc to pass struct xprt to xs_tcp_data_recv */
1418	rd_desc.arg.data = xprt;
1419	do {
1420		rd_desc.count = 65536;
1421		read = tcp_read_sock(sk, &rd_desc, xs_tcp_data_recv);
1422	} while (read > 0);
1423out:
1424	read_unlock_bh(&sk->sk_callback_lock);
1425}
1426
1427/*
1428 * Do the equivalent of linger/linger2 handling for dealing with
1429 * broken servers that don't close the socket in a timely
1430 * fashion
1431 */
1432static void xs_tcp_schedule_linger_timeout(struct rpc_xprt *xprt,
1433		unsigned long timeout)
1434{
1435	struct sock_xprt *transport;
1436
1437	if (xprt_test_and_set_connecting(xprt))
1438		return;
1439	set_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1440	transport = container_of(xprt, struct sock_xprt, xprt);
1441	queue_delayed_work(rpciod_workqueue, &transport->connect_worker,
1442			   timeout);
1443}
1444
1445static void xs_tcp_cancel_linger_timeout(struct rpc_xprt *xprt)
1446{
1447	struct sock_xprt *transport;
1448
1449	transport = container_of(xprt, struct sock_xprt, xprt);
1450
1451	if (!test_bit(XPRT_CONNECTION_ABORT, &xprt->state) ||
1452	    !cancel_delayed_work(&transport->connect_worker))
1453		return;
1454	clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1455	xprt_clear_connecting(xprt);
1456}
1457
1458static void xs_sock_mark_closed(struct rpc_xprt *xprt)
1459{
1460	smp_mb__before_clear_bit();
1461	clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1462	clear_bit(XPRT_CLOSING, &xprt->state);
1463	smp_mb__after_clear_bit();
1464	/* Mark transport as closed and wake up all pending tasks */
1465	xprt_disconnect_done(xprt);
1466}
1467
1468/**
1469 * xs_tcp_state_change - callback to handle TCP socket state changes
1470 * @sk: socket whose state has changed
1471 *
1472 */
1473static void xs_tcp_state_change(struct sock *sk)
1474{
1475	struct rpc_xprt *xprt;
1476
1477	read_lock_bh(&sk->sk_callback_lock);
1478	if (!(xprt = xprt_from_sock(sk)))
1479		goto out;
1480	dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1481	dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1482			sk->sk_state, xprt_connected(xprt),
1483			sock_flag(sk, SOCK_DEAD),
1484			sock_flag(sk, SOCK_ZAPPED),
1485			sk->sk_shutdown);
1486
1487	switch (sk->sk_state) {
1488	case TCP_ESTABLISHED:
1489		spin_lock(&xprt->transport_lock);
1490		if (!xprt_test_and_set_connected(xprt)) {
1491			struct sock_xprt *transport = container_of(xprt,
1492					struct sock_xprt, xprt);
1493
1494			/* Reset TCP record info */
1495			transport->tcp_offset = 0;
1496			transport->tcp_reclen = 0;
1497			transport->tcp_copied = 0;
1498			transport->tcp_flags =
1499				TCP_RCV_COPY_FRAGHDR | TCP_RCV_COPY_XID;
1500
1501			xprt_wake_pending_tasks(xprt, -EAGAIN);
1502		}
1503		spin_unlock(&xprt->transport_lock);
1504		break;
1505	case TCP_FIN_WAIT1:
1506		/* The client initiated a shutdown of the socket */
1507		xprt->connect_cookie++;
1508		xprt->reestablish_timeout = 0;
1509		set_bit(XPRT_CLOSING, &xprt->state);
1510		smp_mb__before_clear_bit();
1511		clear_bit(XPRT_CONNECTED, &xprt->state);
1512		clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1513		smp_mb__after_clear_bit();
1514		xs_tcp_schedule_linger_timeout(xprt, xs_tcp_fin_timeout);
1515		break;
1516	case TCP_CLOSE_WAIT:
1517		/* The server initiated a shutdown of the socket */
1518		xprt_force_disconnect(xprt);
1519		xprt->connect_cookie++;
1520	case TCP_CLOSING:
1521		/*
1522		 * If the server closed down the connection, make sure that
1523		 * we back off before reconnecting
1524		 */
1525		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1526			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1527		break;
1528	case TCP_LAST_ACK:
1529		set_bit(XPRT_CLOSING, &xprt->state);
1530		xs_tcp_schedule_linger_timeout(xprt, xs_tcp_fin_timeout);
1531		smp_mb__before_clear_bit();
1532		clear_bit(XPRT_CONNECTED, &xprt->state);
1533		smp_mb__after_clear_bit();
1534		break;
1535	case TCP_CLOSE:
1536		xs_tcp_cancel_linger_timeout(xprt);
1537		xs_sock_mark_closed(xprt);
1538	}
1539 out:
1540	read_unlock_bh(&sk->sk_callback_lock);
1541}
1542
1543/**
1544 * xs_error_report - callback mainly for catching socket errors
1545 * @sk: socket
1546 */
1547static void xs_error_report(struct sock *sk)
1548{
1549	struct rpc_xprt *xprt;
1550
1551	read_lock_bh(&sk->sk_callback_lock);
1552	if (!(xprt = xprt_from_sock(sk)))
1553		goto out;
1554	dprintk("RPC:       %s client %p...\n"
1555			"RPC:       error %d\n",
1556			__func__, xprt, sk->sk_err);
1557	xprt_wake_pending_tasks(xprt, -EAGAIN);
1558out:
1559	read_unlock_bh(&sk->sk_callback_lock);
1560}
1561
1562static void xs_write_space(struct sock *sk)
1563{
1564	struct socket *sock;
1565	struct rpc_xprt *xprt;
1566
1567	if (unlikely(!(sock = sk->sk_socket)))
1568		return;
1569	clear_bit(SOCK_NOSPACE, &sock->flags);
1570
1571	if (unlikely(!(xprt = xprt_from_sock(sk))))
1572		return;
1573	if (test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags) == 0)
1574		return;
1575
1576	xprt_write_space(xprt);
1577}
1578
1579/**
1580 * xs_udp_write_space - callback invoked when socket buffer space
1581 *                             becomes available
1582 * @sk: socket whose state has changed
1583 *
1584 * Called when more output buffer space is available for this socket.
1585 * We try not to wake our writers until they can make "significant"
1586 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1587 * with a bunch of small requests.
1588 */
1589static void xs_udp_write_space(struct sock *sk)
1590{
1591	read_lock_bh(&sk->sk_callback_lock);
1592
1593	/* from net/core/sock.c:sock_def_write_space */
1594	if (sock_writeable(sk))
1595		xs_write_space(sk);
1596
1597	read_unlock_bh(&sk->sk_callback_lock);
1598}
1599
1600/**
1601 * xs_tcp_write_space - callback invoked when socket buffer space
1602 *                             becomes available
1603 * @sk: socket whose state has changed
1604 *
1605 * Called when more output buffer space is available for this socket.
1606 * We try not to wake our writers until they can make "significant"
1607 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1608 * with a bunch of small requests.
1609 */
1610static void xs_tcp_write_space(struct sock *sk)
1611{
1612	read_lock_bh(&sk->sk_callback_lock);
1613
1614	/* from net/core/stream.c:sk_stream_write_space */
1615	if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk))
1616		xs_write_space(sk);
1617
1618	read_unlock_bh(&sk->sk_callback_lock);
1619}
1620
1621static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1622{
1623	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1624	struct sock *sk = transport->inet;
1625
1626	if (transport->rcvsize) {
1627		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1628		sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1629	}
1630	if (transport->sndsize) {
1631		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1632		sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1633		sk->sk_write_space(sk);
1634	}
1635}
1636
1637/**
1638 * xs_udp_set_buffer_size - set send and receive limits
1639 * @xprt: generic transport
1640 * @sndsize: requested size of send buffer, in bytes
1641 * @rcvsize: requested size of receive buffer, in bytes
1642 *
1643 * Set socket send and receive buffer size limits.
1644 */
1645static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1646{
1647	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1648
1649	transport->sndsize = 0;
1650	if (sndsize)
1651		transport->sndsize = sndsize + 1024;
1652	transport->rcvsize = 0;
1653	if (rcvsize)
1654		transport->rcvsize = rcvsize + 1024;
1655
1656	xs_udp_do_set_buffer_size(xprt);
1657}
1658
1659/**
1660 * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1661 * @task: task that timed out
1662 *
1663 * Adjust the congestion window after a retransmit timeout has occurred.
1664 */
1665static void xs_udp_timer(struct rpc_task *task)
1666{
1667	xprt_adjust_cwnd(task, -ETIMEDOUT);
1668}
1669
1670static unsigned short xs_get_random_port(void)
1671{
1672	unsigned short range = xprt_max_resvport - xprt_min_resvport;
1673	unsigned short rand = (unsigned short) net_random() % range;
1674	return rand + xprt_min_resvport;
1675}
1676
1677/**
1678 * xs_set_port - reset the port number in the remote endpoint address
1679 * @xprt: generic transport
1680 * @port: new port number
1681 *
1682 */
1683static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1684{
1685	dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1686
1687	rpc_set_port(xs_addr(xprt), port);
1688	xs_update_peer_port(xprt);
1689}
1690
1691static unsigned short xs_get_srcport(struct sock_xprt *transport)
1692{
1693	unsigned short port = transport->srcport;
1694
1695	if (port == 0 && transport->xprt.resvport)
1696		port = xs_get_random_port();
1697	return port;
1698}
1699
1700static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1701{
1702	if (transport->srcport != 0)
1703		transport->srcport = 0;
1704	if (!transport->xprt.resvport)
1705		return 0;
1706	if (port <= xprt_min_resvport || port > xprt_max_resvport)
1707		return xprt_max_resvport;
1708	return --port;
1709}
1710static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1711{
1712	struct sockaddr_storage myaddr;
1713	int err, nloop = 0;
1714	unsigned short port = xs_get_srcport(transport);
1715	unsigned short last;
1716
1717	memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1718	do {
1719		rpc_set_port((struct sockaddr *)&myaddr, port);
1720		err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1721				transport->xprt.addrlen);
1722		if (port == 0)
1723			break;
1724		if (err == 0) {
1725			transport->srcport = port;
1726			break;
1727		}
1728		last = port;
1729		port = xs_next_srcport(transport, port);
1730		if (port > last)
1731			nloop++;
1732	} while (err == -EADDRINUSE && nloop != 2);
1733
1734	if (myaddr.ss_family == AF_INET)
1735		dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1736				&((struct sockaddr_in *)&myaddr)->sin_addr,
1737				port, err ? "failed" : "ok", err);
1738	else
1739		dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1740				&((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1741				port, err ? "failed" : "ok", err);
1742	return err;
1743}
1744
1745/*
1746 * We don't support autobind on AF_LOCAL sockets
1747 */
1748static void xs_local_rpcbind(struct rpc_task *task)
1749{
1750	xprt_set_bound(task->tk_xprt);
1751}
1752
1753static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1754{
1755}
1756
1757#ifdef CONFIG_DEBUG_LOCK_ALLOC
1758static struct lock_class_key xs_key[2];
1759static struct lock_class_key xs_slock_key[2];
1760
1761static inline void xs_reclassify_socketu(struct socket *sock)
1762{
1763	struct sock *sk = sock->sk;
1764
1765	BUG_ON(sock_owned_by_user(sk));
1766	sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1767		&xs_slock_key[1], "sk_lock-AF_LOCAL-RPC", &xs_key[1]);
1768}
1769
1770static inline void xs_reclassify_socket4(struct socket *sock)
1771{
1772	struct sock *sk = sock->sk;
1773
1774	BUG_ON(sock_owned_by_user(sk));
1775	sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1776		&xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1777}
1778
1779static inline void xs_reclassify_socket6(struct socket *sock)
1780{
1781	struct sock *sk = sock->sk;
1782
1783	BUG_ON(sock_owned_by_user(sk));
1784	sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1785		&xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1786}
1787
1788static inline void xs_reclassify_socket(int family, struct socket *sock)
1789{
1790	switch (family) {
1791	case AF_LOCAL:
1792		xs_reclassify_socketu(sock);
1793		break;
1794	case AF_INET:
1795		xs_reclassify_socket4(sock);
1796		break;
1797	case AF_INET6:
1798		xs_reclassify_socket6(sock);
1799		break;
1800	}
1801}
1802#else
1803static inline void xs_reclassify_socketu(struct socket *sock)
1804{
1805}
1806
1807static inline void xs_reclassify_socket4(struct socket *sock)
1808{
1809}
1810
1811static inline void xs_reclassify_socket6(struct socket *sock)
1812{
1813}
1814
1815static inline void xs_reclassify_socket(int family, struct socket *sock)
1816{
1817}
1818#endif
1819
1820static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1821		struct sock_xprt *transport, int family, int type, int protocol)
1822{
1823	struct socket *sock;
1824	int err;
1825
1826	err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1827	if (err < 0) {
1828		dprintk("RPC:       can't create %d transport socket (%d).\n",
1829				protocol, -err);
1830		goto out;
1831	}
1832	xs_reclassify_socket(family, sock);
1833
1834	err = xs_bind(transport, sock);
1835	if (err) {
1836		sock_release(sock);
1837		goto out;
1838	}
1839
1840	return sock;
1841out:
1842	return ERR_PTR(err);
1843}
1844
1845static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1846				      struct socket *sock)
1847{
1848	struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1849									xprt);
1850
1851	if (!transport->inet) {
1852		struct sock *sk = sock->sk;
1853
1854		write_lock_bh(&sk->sk_callback_lock);
1855
1856		xs_save_old_callbacks(transport, sk);
1857
1858		sk->sk_user_data = xprt;
1859		sk->sk_data_ready = xs_local_data_ready;
1860		sk->sk_write_space = xs_udp_write_space;
1861		sk->sk_error_report = xs_error_report;
1862		sk->sk_allocation = GFP_ATOMIC;
1863
1864		xprt_clear_connected(xprt);
1865
1866		/* Reset to new socket */
1867		transport->sock = sock;
1868		transport->inet = sk;
1869
1870		write_unlock_bh(&sk->sk_callback_lock);
1871	}
1872
1873	/* Tell the socket layer to start connecting... */
1874	xprt->stat.connect_count++;
1875	xprt->stat.connect_start = jiffies;
1876	return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1877}
1878
1879/**
1880 * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1881 * @xprt: RPC transport to connect
1882 * @transport: socket transport to connect
1883 * @create_sock: function to create a socket of the correct type
1884 *
1885 * Invoked by a work queue tasklet.
1886 */
1887static void xs_local_setup_socket(struct work_struct *work)
1888{
1889	struct sock_xprt *transport =
1890		container_of(work, struct sock_xprt, connect_worker.work);
1891	struct rpc_xprt *xprt = &transport->xprt;
1892	struct socket *sock;
1893	int status = -EIO;
1894
1895	if (xprt->shutdown)
1896		goto out;
1897
1898	current->flags |= PF_FSTRANS;
1899
1900	clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1901	status = __sock_create(xprt->xprt_net, AF_LOCAL,
1902					SOCK_STREAM, 0, &sock, 1);
1903	if (status < 0) {
1904		dprintk("RPC:       can't create AF_LOCAL "
1905			"transport socket (%d).\n", -status);
1906		goto out;
1907	}
1908	xs_reclassify_socketu(sock);
1909
1910	dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
1911			xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1912
1913	status = xs_local_finish_connecting(xprt, sock);
1914	switch (status) {
1915	case 0:
1916		dprintk("RPC:       xprt %p connected to %s\n",
1917				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1918		xprt_set_connected(xprt);
1919		break;
1920	case -ENOENT:
1921		dprintk("RPC:       xprt %p: socket %s does not exist\n",
1922				xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1923		break;
1924	default:
1925		printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
1926				__func__, -status,
1927				xprt->address_strings[RPC_DISPLAY_ADDR]);
1928	}
1929
1930out:
1931	xprt_clear_connecting(xprt);
1932	xprt_wake_pending_tasks(xprt, status);
1933	current->flags &= ~PF_FSTRANS;
1934}
1935
1936static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
1937{
1938	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1939
1940	if (!transport->inet) {
1941		struct sock *sk = sock->sk;
1942
1943		write_lock_bh(&sk->sk_callback_lock);
1944
1945		xs_save_old_callbacks(transport, sk);
1946
1947		sk->sk_user_data = xprt;
1948		sk->sk_data_ready = xs_udp_data_ready;
1949		sk->sk_write_space = xs_udp_write_space;
1950		sk->sk_error_report = xs_error_report;
1951		sk->sk_no_check = UDP_CSUM_NORCV;
1952		sk->sk_allocation = GFP_ATOMIC;
1953
1954		xprt_set_connected(xprt);
1955
1956		/* Reset to new socket */
1957		transport->sock = sock;
1958		transport->inet = sk;
1959
1960		write_unlock_bh(&sk->sk_callback_lock);
1961	}
1962	xs_udp_do_set_buffer_size(xprt);
1963}
1964
1965static void xs_udp_setup_socket(struct work_struct *work)
1966{
1967	struct sock_xprt *transport =
1968		container_of(work, struct sock_xprt, connect_worker.work);
1969	struct rpc_xprt *xprt = &transport->xprt;
1970	struct socket *sock = transport->sock;
1971	int status = -EIO;
1972
1973	if (xprt->shutdown)
1974		goto out;
1975
1976	current->flags |= PF_FSTRANS;
1977
1978	/* Start by resetting any existing state */
1979	xs_reset_transport(transport);
1980	sock = xs_create_sock(xprt, transport,
1981			xs_addr(xprt)->sa_family, SOCK_DGRAM, IPPROTO_UDP);
1982	if (IS_ERR(sock))
1983		goto out;
1984
1985	dprintk("RPC:       worker connecting xprt %p via %s to "
1986				"%s (port %s)\n", xprt,
1987			xprt->address_strings[RPC_DISPLAY_PROTO],
1988			xprt->address_strings[RPC_DISPLAY_ADDR],
1989			xprt->address_strings[RPC_DISPLAY_PORT]);
1990
1991	xs_udp_finish_connecting(xprt, sock);
1992	status = 0;
1993out:
1994	xprt_clear_connecting(xprt);
1995	xprt_wake_pending_tasks(xprt, status);
1996	current->flags &= ~PF_FSTRANS;
1997}
1998
1999/*
2000 * We need to preserve the port number so the reply cache on the server can
2001 * find our cached RPC replies when we get around to reconnecting.
2002 */
2003static void xs_abort_connection(struct sock_xprt *transport)
2004{
2005	int result;
2006	struct sockaddr any;
2007
2008	dprintk("RPC:       disconnecting xprt %p to reuse port\n", transport);
2009
2010	/*
2011	 * Disconnect the transport socket by doing a connect operation
2012	 * with AF_UNSPEC.  This should return immediately...
2013	 */
2014	memset(&any, 0, sizeof(any));
2015	any.sa_family = AF_UNSPEC;
2016	result = kernel_connect(transport->sock, &any, sizeof(any), 0);
2017	if (!result)
2018		xs_sock_mark_closed(&transport->xprt);
2019	else
2020		dprintk("RPC:       AF_UNSPEC connect return code %d\n",
2021				result);
2022}
2023
2024static void xs_tcp_reuse_connection(struct sock_xprt *transport)
2025{
2026	unsigned int state = transport->inet->sk_state;
2027
2028	if (state == TCP_CLOSE && transport->sock->state == SS_UNCONNECTED) {
2029		/* we don't need to abort the connection if the socket
2030		 * hasn't undergone a shutdown
2031		 */
2032		if (transport->inet->sk_shutdown == 0)
2033			return;
2034		dprintk("RPC:       %s: TCP_CLOSEd and sk_shutdown set to %d\n",
2035				__func__, transport->inet->sk_shutdown);
2036	}
2037	if ((1 << state) & (TCPF_ESTABLISHED|TCPF_SYN_SENT)) {
2038		/* we don't need to abort the connection if the socket
2039		 * hasn't undergone a shutdown
2040		 */
2041		if (transport->inet->sk_shutdown == 0)
2042			return;
2043		dprintk("RPC:       %s: ESTABLISHED/SYN_SENT "
2044				"sk_shutdown set to %d\n",
2045				__func__, transport->inet->sk_shutdown);
2046	}
2047	xs_abort_connection(transport);
2048}
2049
2050static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2051{
2052	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2053	int ret = -ENOTCONN;
2054
2055	if (!transport->inet) {
2056		struct sock *sk = sock->sk;
2057
2058		write_lock_bh(&sk->sk_callback_lock);
2059
2060		xs_save_old_callbacks(transport, sk);
2061
2062		sk->sk_user_data = xprt;
2063		sk->sk_data_ready = xs_tcp_data_ready;
2064		sk->sk_state_change = xs_tcp_state_change;
2065		sk->sk_write_space = xs_tcp_write_space;
2066		sk->sk_error_report = xs_error_report;
2067		sk->sk_allocation = GFP_ATOMIC;
2068
2069		/* socket options */
2070		sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
2071		sock_reset_flag(sk, SOCK_LINGER);
2072		tcp_sk(sk)->linger2 = 0;
2073		tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
2074
2075		xprt_clear_connected(xprt);
2076
2077		/* Reset to new socket */
2078		transport->sock = sock;
2079		transport->inet = sk;
2080
2081		write_unlock_bh(&sk->sk_callback_lock);
2082	}
2083
2084	if (!xprt_bound(xprt))
2085		goto out;
2086
2087	/* Tell the socket layer to start connecting... */
2088	xprt->stat.connect_count++;
2089	xprt->stat.connect_start = jiffies;
2090	ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2091	switch (ret) {
2092	case 0:
2093	case -EINPROGRESS:
2094		/* SYN_SENT! */
2095		xprt->connect_cookie++;
2096		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2097			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2098	}
2099out:
2100	return ret;
2101}
2102
2103/**
2104 * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2105 * @xprt: RPC transport to connect
2106 * @transport: socket transport to connect
2107 * @create_sock: function to create a socket of the correct type
2108 *
2109 * Invoked by a work queue tasklet.
2110 */
2111static void xs_tcp_setup_socket(struct work_struct *work)
2112{
2113	struct sock_xprt *transport =
2114		container_of(work, struct sock_xprt, connect_worker.work);
2115	struct socket *sock = transport->sock;
2116	struct rpc_xprt *xprt = &transport->xprt;
2117	int status = -EIO;
2118
2119	if (xprt->shutdown)
2120		goto out;
2121
2122	current->flags |= PF_FSTRANS;
2123
2124	if (!sock) {
2125		clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
2126		sock = xs_create_sock(xprt, transport,
2127				xs_addr(xprt)->sa_family, SOCK_STREAM, IPPROTO_TCP);
2128		if (IS_ERR(sock)) {
2129			status = PTR_ERR(sock);
2130			goto out;
2131		}
2132	} else {
2133		int abort_and_exit;
2134
2135		abort_and_exit = test_and_clear_bit(XPRT_CONNECTION_ABORT,
2136				&xprt->state);
2137		/* "close" the socket, preserving the local port */
2138		xs_tcp_reuse_connection(transport);
2139
2140		if (abort_and_exit)
2141			goto out_eagain;
2142	}
2143
2144	dprintk("RPC:       worker connecting xprt %p via %s to "
2145				"%s (port %s)\n", xprt,
2146			xprt->address_strings[RPC_DISPLAY_PROTO],
2147			xprt->address_strings[RPC_DISPLAY_ADDR],
2148			xprt->address_strings[RPC_DISPLAY_PORT]);
2149
2150	status = xs_tcp_finish_connecting(xprt, sock);
2151	dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2152			xprt, -status, xprt_connected(xprt),
2153			sock->sk->sk_state);
2154	switch (status) {
2155	default:
2156		printk("%s: connect returned unhandled error %d\n",
2157			__func__, status);
2158	case -EADDRNOTAVAIL:
2159		/* We're probably in TIME_WAIT. Get rid of existing socket,
2160		 * and retry
2161		 */
2162		set_bit(XPRT_CONNECTION_CLOSE, &xprt->state);
2163		xprt_force_disconnect(xprt);
2164		break;
2165	case -ECONNREFUSED:
2166	case -ECONNRESET:
2167	case -ENETUNREACH:
2168		/* retry with existing socket, after a delay */
2169	case 0:
2170	case -EINPROGRESS:
2171	case -EALREADY:
2172		xprt_clear_connecting(xprt);
2173		current->flags &= ~PF_FSTRANS;
2174		return;
2175	case -EINVAL:
2176		/* Happens, for instance, if the user specified a link
2177		 * local IPv6 address without a scope-id.
2178		 */
2179		goto out;
2180	}
2181out_eagain:
2182	status = -EAGAIN;
2183out:
2184	xprt_clear_connecting(xprt);
2185	xprt_wake_pending_tasks(xprt, status);
2186	current->flags &= ~PF_FSTRANS;
2187}
2188
2189/**
2190 * xs_connect - connect a socket to a remote endpoint
2191 * @task: address of RPC task that manages state of connect request
2192 *
2193 * TCP: If the remote end dropped the connection, delay reconnecting.
2194 *
2195 * UDP socket connects are synchronous, but we use a work queue anyway
2196 * to guarantee that even unprivileged user processes can set up a
2197 * socket on a privileged port.
2198 *
2199 * If a UDP socket connect fails, the delay behavior here prevents
2200 * retry floods (hard mounts).
2201 */
2202static void xs_connect(struct rpc_task *task)
2203{
2204	struct rpc_xprt *xprt = task->tk_xprt;
2205	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2206
2207	if (transport->sock != NULL && !RPC_IS_SOFTCONN(task)) {
2208		dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2209				"seconds\n",
2210				xprt, xprt->reestablish_timeout / HZ);
2211		queue_delayed_work(rpciod_workqueue,
2212				   &transport->connect_worker,
2213				   xprt->reestablish_timeout);
2214		xprt->reestablish_timeout <<= 1;
2215		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2216			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2217		if (xprt->reestablish_timeout > XS_TCP_MAX_REEST_TO)
2218			xprt->reestablish_timeout = XS_TCP_MAX_REEST_TO;
2219	} else {
2220		dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2221		queue_delayed_work(rpciod_workqueue,
2222				   &transport->connect_worker, 0);
2223	}
2224}
2225
2226/**
2227 * xs_local_print_stats - display AF_LOCAL socket-specifc stats
2228 * @xprt: rpc_xprt struct containing statistics
2229 * @seq: output file
2230 *
2231 */
2232static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2233{
2234	long idle_time = 0;
2235
2236	if (xprt_connected(xprt))
2237		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2238
2239	seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2240			"%llu %llu %lu %llu %llu\n",
2241			xprt->stat.bind_count,
2242			xprt->stat.connect_count,
2243			xprt->stat.connect_time,
2244			idle_time,
2245			xprt->stat.sends,
2246			xprt->stat.recvs,
2247			xprt->stat.bad_xids,
2248			xprt->stat.req_u,
2249			xprt->stat.bklog_u,
2250			xprt->stat.max_slots,
2251			xprt->stat.sending_u,
2252			xprt->stat.pending_u);
2253}
2254
2255/**
2256 * xs_udp_print_stats - display UDP socket-specifc stats
2257 * @xprt: rpc_xprt struct containing statistics
2258 * @seq: output file
2259 *
2260 */
2261static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2262{
2263	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2264
2265	seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2266			"%lu %llu %llu\n",
2267			transport->srcport,
2268			xprt->stat.bind_count,
2269			xprt->stat.sends,
2270			xprt->stat.recvs,
2271			xprt->stat.bad_xids,
2272			xprt->stat.req_u,
2273			xprt->stat.bklog_u,
2274			xprt->stat.max_slots,
2275			xprt->stat.sending_u,
2276			xprt->stat.pending_u);
2277}
2278
2279/**
2280 * xs_tcp_print_stats - display TCP socket-specifc stats
2281 * @xprt: rpc_xprt struct containing statistics
2282 * @seq: output file
2283 *
2284 */
2285static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2286{
2287	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2288	long idle_time = 0;
2289
2290	if (xprt_connected(xprt))
2291		idle_time = (long)(jiffies - xprt->last_used) / HZ;
2292
2293	seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2294			"%llu %llu %lu %llu %llu\n",
2295			transport->srcport,
2296			xprt->stat.bind_count,
2297			xprt->stat.connect_count,
2298			xprt->stat.connect_time,
2299			idle_time,
2300			xprt->stat.sends,
2301			xprt->stat.recvs,
2302			xprt->stat.bad_xids,
2303			xprt->stat.req_u,
2304			xprt->stat.bklog_u,
2305			xprt->stat.max_slots,
2306			xprt->stat.sending_u,
2307			xprt->stat.pending_u);
2308}
2309
2310/*
2311 * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2312 * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2313 * to use the server side send routines.
2314 */
2315static void *bc_malloc(struct rpc_task *task, size_t size)
2316{
2317	struct page *page;
2318	struct rpc_buffer *buf;
2319
2320	BUG_ON(size > PAGE_SIZE - sizeof(struct rpc_buffer));
2321	page = alloc_page(GFP_KERNEL);
2322
2323	if (!page)
2324		return NULL;
2325
2326	buf = page_address(page);
2327	buf->len = PAGE_SIZE;
2328
2329	return buf->data;
2330}
2331
2332/*
2333 * Free the space allocated in the bc_alloc routine
2334 */
2335static void bc_free(void *buffer)
2336{
2337	struct rpc_buffer *buf;
2338
2339	if (!buffer)
2340		return;
2341
2342	buf = container_of(buffer, struct rpc_buffer, data);
2343	free_page((unsigned long)buf);
2344}
2345
2346/*
2347 * Use the svc_sock to send the callback. Must be called with svsk->sk_mutex
2348 * held. Borrows heavily from svc_tcp_sendto and xs_tcp_send_request.
2349 */
2350static int bc_sendto(struct rpc_rqst *req)
2351{
2352	int len;
2353	struct xdr_buf *xbufp = &req->rq_snd_buf;
2354	struct rpc_xprt *xprt = req->rq_xprt;
2355	struct sock_xprt *transport =
2356				container_of(xprt, struct sock_xprt, xprt);
2357	struct socket *sock = transport->sock;
2358	unsigned long headoff;
2359	unsigned long tailoff;
2360
2361	xs_encode_stream_record_marker(xbufp);
2362
2363	tailoff = (unsigned long)xbufp->tail[0].iov_base & ~PAGE_MASK;
2364	headoff = (unsigned long)xbufp->head[0].iov_base & ~PAGE_MASK;
2365	len = svc_send_common(sock, xbufp,
2366			      virt_to_page(xbufp->head[0].iov_base), headoff,
2367			      xbufp->tail[0].iov_base, tailoff);
2368
2369	if (len != xbufp->len) {
2370		printk(KERN_NOTICE "Error sending entire callback!\n");
2371		len = -EAGAIN;
2372	}
2373
2374	return len;
2375}
2376
2377/*
2378 * The send routine. Borrows from svc_send
2379 */
2380static int bc_send_request(struct rpc_task *task)
2381{
2382	struct rpc_rqst *req = task->tk_rqstp;
2383	struct svc_xprt	*xprt;
2384	struct svc_sock         *svsk;
2385	u32                     len;
2386
2387	dprintk("sending request with xid: %08x\n", ntohl(req->rq_xid));
2388	/*
2389	 * Get the server socket associated with this callback xprt
2390	 */
2391	xprt = req->rq_xprt->bc_xprt;
2392	svsk = container_of(xprt, struct svc_sock, sk_xprt);
2393
2394	/*
2395	 * Grab the mutex to serialize data as the connection is shared
2396	 * with the fore channel
2397	 */
2398	if (!mutex_trylock(&xprt->xpt_mutex)) {
2399		rpc_sleep_on(&xprt->xpt_bc_pending, task, NULL);
2400		if (!mutex_trylock(&xprt->xpt_mutex))
2401			return -EAGAIN;
2402		rpc_wake_up_queued_task(&xprt->xpt_bc_pending, task);
2403	}
2404	if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2405		len = -ENOTCONN;
2406	else
2407		len = bc_sendto(req);
2408	mutex_unlock(&xprt->xpt_mutex);
2409
2410	if (len > 0)
2411		len = 0;
2412
2413	return len;
2414}
2415
2416/*
2417 * The close routine. Since this is client initiated, we do nothing
2418 */
2419
2420static void bc_close(struct rpc_xprt *xprt)
2421{
2422}
2423
2424/*
2425 * The xprt destroy routine. Again, because this connection is client
2426 * initiated, we do nothing
2427 */
2428
2429static void bc_destroy(struct rpc_xprt *xprt)
2430{
2431}
2432
2433static struct rpc_xprt_ops xs_local_ops = {
2434	.reserve_xprt		= xprt_reserve_xprt,
2435	.release_xprt		= xs_tcp_release_xprt,
2436	.rpcbind		= xs_local_rpcbind,
2437	.set_port		= xs_local_set_port,
2438	.connect		= xs_connect,
2439	.buf_alloc		= rpc_malloc,
2440	.buf_free		= rpc_free,
2441	.send_request		= xs_local_send_request,
2442	.set_retrans_timeout	= xprt_set_retrans_timeout_def,
2443	.close			= xs_close,
2444	.destroy		= xs_destroy,
2445	.print_stats		= xs_local_print_stats,
2446};
2447
2448static struct rpc_xprt_ops xs_udp_ops = {
2449	.set_buffer_size	= xs_udp_set_buffer_size,
2450	.reserve_xprt		= xprt_reserve_xprt_cong,
2451	.release_xprt		= xprt_release_xprt_cong,
2452	.rpcbind		= rpcb_getport_async,
2453	.set_port		= xs_set_port,
2454	.connect		= xs_connect,
2455	.buf_alloc		= rpc_malloc,
2456	.buf_free		= rpc_free,
2457	.send_request		= xs_udp_send_request,
2458	.set_retrans_timeout	= xprt_set_retrans_timeout_rtt,
2459	.timer			= xs_udp_timer,
2460	.release_request	= xprt_release_rqst_cong,
2461	.close			= xs_close,
2462	.destroy		= xs_destroy,
2463	.print_stats		= xs_udp_print_stats,
2464};
2465
2466static struct rpc_xprt_ops xs_tcp_ops = {
2467	.reserve_xprt		= xprt_reserve_xprt,
2468	.release_xprt		= xs_tcp_release_xprt,
2469	.rpcbind		= rpcb_getport_async,
2470	.set_port		= xs_set_port,
2471	.connect		= xs_connect,
2472	.buf_alloc		= rpc_malloc,
2473	.buf_free		= rpc_free,
2474	.send_request		= xs_tcp_send_request,
2475	.set_retrans_timeout	= xprt_set_retrans_timeout_def,
2476	.close			= xs_tcp_close,
2477	.destroy		= xs_destroy,
2478	.print_stats		= xs_tcp_print_stats,
2479};
2480
2481/*
2482 * The rpc_xprt_ops for the server backchannel
2483 */
2484
2485static struct rpc_xprt_ops bc_tcp_ops = {
2486	.reserve_xprt		= xprt_reserve_xprt,
2487	.release_xprt		= xprt_release_xprt,
2488	.rpcbind		= xs_local_rpcbind,
2489	.buf_alloc		= bc_malloc,
2490	.buf_free		= bc_free,
2491	.send_request		= bc_send_request,
2492	.set_retrans_timeout	= xprt_set_retrans_timeout_def,
2493	.close			= bc_close,
2494	.destroy		= bc_destroy,
2495	.print_stats		= xs_tcp_print_stats,
2496};
2497
2498static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2499{
2500	static const struct sockaddr_in sin = {
2501		.sin_family		= AF_INET,
2502		.sin_addr.s_addr	= htonl(INADDR_ANY),
2503	};
2504	static const struct sockaddr_in6 sin6 = {
2505		.sin6_family		= AF_INET6,
2506		.sin6_addr		= IN6ADDR_ANY_INIT,
2507	};
2508
2509	switch (family) {
2510	case AF_LOCAL:
2511		break;
2512	case AF_INET:
2513		memcpy(sap, &sin, sizeof(sin));
2514		break;
2515	case AF_INET6:
2516		memcpy(sap, &sin6, sizeof(sin6));
2517		break;
2518	default:
2519		dprintk("RPC:       %s: Bad address family\n", __func__);
2520		return -EAFNOSUPPORT;
2521	}
2522	return 0;
2523}
2524
2525static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2526				      unsigned int slot_table_size,
2527				      unsigned int max_slot_table_size)
2528{
2529	struct rpc_xprt *xprt;
2530	struct sock_xprt *new;
2531
2532	if (args->addrlen > sizeof(xprt->addr)) {
2533		dprintk("RPC:       xs_setup_xprt: address too large\n");
2534		return ERR_PTR(-EBADF);
2535	}
2536
2537	xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2538			max_slot_table_size);
2539	if (xprt == NULL) {
2540		dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2541				"rpc_xprt\n");
2542		return ERR_PTR(-ENOMEM);
2543	}
2544
2545	new = container_of(xprt, struct sock_xprt, xprt);
2546	memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2547	xprt->addrlen = args->addrlen;
2548	if (args->srcaddr)
2549		memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2550	else {
2551		int err;
2552		err = xs_init_anyaddr(args->dstaddr->sa_family,
2553					(struct sockaddr *)&new->srcaddr);
2554		if (err != 0) {
2555			xprt_free(xprt);
2556			return ERR_PTR(err);
2557		}
2558	}
2559
2560	return xprt;
2561}
2562
2563static const struct rpc_timeout xs_local_default_timeout = {
2564	.to_initval = 10 * HZ,
2565	.to_maxval = 10 * HZ,
2566	.to_retries = 2,
2567};
2568
2569/**
2570 * xs_setup_local - Set up transport to use an AF_LOCAL socket
2571 * @args: rpc transport creation arguments
2572 *
2573 * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2574 */
2575static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2576{
2577	struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2578	struct sock_xprt *transport;
2579	struct rpc_xprt *xprt;
2580	struct rpc_xprt *ret;
2581
2582	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2583			xprt_max_tcp_slot_table_entries);
2584	if (IS_ERR(xprt))
2585		return xprt;
2586	transport = container_of(xprt, struct sock_xprt, xprt);
2587
2588	xprt->prot = 0;
2589	xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2590	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2591
2592	xprt->bind_timeout = XS_BIND_TO;
2593	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2594	xprt->idle_timeout = XS_IDLE_DISC_TO;
2595
2596	xprt->ops = &xs_local_ops;
2597	xprt->timeout = &xs_local_default_timeout;
2598
2599	switch (sun->sun_family) {
2600	case AF_LOCAL:
2601		if (sun->sun_path[0] != '/') {
2602			dprintk("RPC:       bad AF_LOCAL address: %s\n",
2603					sun->sun_path);
2604			ret = ERR_PTR(-EINVAL);
2605			goto out_err;
2606		}
2607		xprt_set_bound(xprt);
2608		INIT_DELAYED_WORK(&transport->connect_worker,
2609					xs_local_setup_socket);
2610		xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
2611		break;
2612	default:
2613		ret = ERR_PTR(-EAFNOSUPPORT);
2614		goto out_err;
2615	}
2616
2617	dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
2618			xprt->address_strings[RPC_DISPLAY_ADDR]);
2619
2620	if (try_module_get(THIS_MODULE))
2621		return xprt;
2622	ret = ERR_PTR(-EINVAL);
2623out_err:
2624	xprt_free(xprt);
2625	return ret;
2626}
2627
2628static const struct rpc_timeout xs_udp_default_timeout = {
2629	.to_initval = 5 * HZ,
2630	.to_maxval = 30 * HZ,
2631	.to_increment = 5 * HZ,
2632	.to_retries = 5,
2633};
2634
2635/**
2636 * xs_setup_udp - Set up transport to use a UDP socket
2637 * @args: rpc transport creation arguments
2638 *
2639 */
2640static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2641{
2642	struct sockaddr *addr = args->dstaddr;
2643	struct rpc_xprt *xprt;
2644	struct sock_xprt *transport;
2645	struct rpc_xprt *ret;
2646
2647	xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2648			xprt_udp_slot_table_entries);
2649	if (IS_ERR(xprt))
2650		return xprt;
2651	transport = container_of(xprt, struct sock_xprt, xprt);
2652
2653	xprt->prot = IPPROTO_UDP;
2654	xprt->tsh_size = 0;
2655	/* XXX: header size can vary due to auth type, IPv6, etc. */
2656	xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2657
2658	xprt->bind_timeout = XS_BIND_TO;
2659	xprt->reestablish_timeout = XS_UDP_REEST_TO;
2660	xprt->idle_timeout = XS_IDLE_DISC_TO;
2661
2662	xprt->ops = &xs_udp_ops;
2663
2664	xprt->timeout = &xs_udp_default_timeout;
2665
2666	switch (addr->sa_family) {
2667	case AF_INET:
2668		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2669			xprt_set_bound(xprt);
2670
2671		INIT_DELAYED_WORK(&transport->connect_worker,
2672					xs_udp_setup_socket);
2673		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2674		break;
2675	case AF_INET6:
2676		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2677			xprt_set_bound(xprt);
2678
2679		INIT_DELAYED_WORK(&transport->connect_worker,
2680					xs_udp_setup_socket);
2681		xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2682		break;
2683	default:
2684		ret = ERR_PTR(-EAFNOSUPPORT);
2685		goto out_err;
2686	}
2687
2688	if (xprt_bound(xprt))
2689		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2690				xprt->address_strings[RPC_DISPLAY_ADDR],
2691				xprt->address_strings[RPC_DISPLAY_PORT],
2692				xprt->address_strings[RPC_DISPLAY_PROTO]);
2693	else
2694		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2695				xprt->address_strings[RPC_DISPLAY_ADDR],
2696				xprt->address_strings[RPC_DISPLAY_PROTO]);
2697
2698	if (try_module_get(THIS_MODULE))
2699		return xprt;
2700	ret = ERR_PTR(-EINVAL);
2701out_err:
2702	xprt_free(xprt);
2703	return ret;
2704}
2705
2706static const struct rpc_timeout xs_tcp_default_timeout = {
2707	.to_initval = 60 * HZ,
2708	.to_maxval = 60 * HZ,
2709	.to_retries = 2,
2710};
2711
2712/**
2713 * xs_setup_tcp - Set up transport to use a TCP socket
2714 * @args: rpc transport creation arguments
2715 *
2716 */
2717static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2718{
2719	struct sockaddr *addr = args->dstaddr;
2720	struct rpc_xprt *xprt;
2721	struct sock_xprt *transport;
2722	struct rpc_xprt *ret;
2723
2724	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2725			xprt_max_tcp_slot_table_entries);
2726	if (IS_ERR(xprt))
2727		return xprt;
2728	transport = container_of(xprt, struct sock_xprt, xprt);
2729
2730	xprt->prot = IPPROTO_TCP;
2731	xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2732	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2733
2734	xprt->bind_timeout = XS_BIND_TO;
2735	xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2736	xprt->idle_timeout = XS_IDLE_DISC_TO;
2737
2738	xprt->ops = &xs_tcp_ops;
2739	xprt->timeout = &xs_tcp_default_timeout;
2740
2741	switch (addr->sa_family) {
2742	case AF_INET:
2743		if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2744			xprt_set_bound(xprt);
2745
2746		INIT_DELAYED_WORK(&transport->connect_worker,
2747					xs_tcp_setup_socket);
2748		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
2749		break;
2750	case AF_INET6:
2751		if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2752			xprt_set_bound(xprt);
2753
2754		INIT_DELAYED_WORK(&transport->connect_worker,
2755					xs_tcp_setup_socket);
2756		xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
2757		break;
2758	default:
2759		ret = ERR_PTR(-EAFNOSUPPORT);
2760		goto out_err;
2761	}
2762
2763	if (xprt_bound(xprt))
2764		dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2765				xprt->address_strings[RPC_DISPLAY_ADDR],
2766				xprt->address_strings[RPC_DISPLAY_PORT],
2767				xprt->address_strings[RPC_DISPLAY_PROTO]);
2768	else
2769		dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2770				xprt->address_strings[RPC_DISPLAY_ADDR],
2771				xprt->address_strings[RPC_DISPLAY_PROTO]);
2772
2773
2774	if (try_module_get(THIS_MODULE))
2775		return xprt;
2776	ret = ERR_PTR(-EINVAL);
2777out_err:
2778	xprt_free(xprt);
2779	return ret;
2780}
2781
2782/**
2783 * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
2784 * @args: rpc transport creation arguments
2785 *
2786 */
2787static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
2788{
2789	struct sockaddr *addr = args->dstaddr;
2790	struct rpc_xprt *xprt;
2791	struct sock_xprt *transport;
2792	struct svc_sock *bc_sock;
2793	struct rpc_xprt *ret;
2794
2795	if (args->bc_xprt->xpt_bc_xprt) {
2796		/*
2797		 * This server connection already has a backchannel
2798		 * export; we can't create a new one, as we wouldn't be
2799		 * able to match replies based on xid any more.  So,
2800		 * reuse the already-existing one:
2801		 */
2802		 return args->bc_xprt->xpt_bc_xprt;
2803	}
2804	xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2805			xprt_tcp_slot_table_entries);
2806	if (IS_ERR(xprt))
2807		return xprt;
2808	transport = container_of(xprt, struct sock_xprt, xprt);
2809
2810	xprt->prot = IPPROTO_TCP;
2811	xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2812	xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2813	xprt->timeout = &xs_tcp_default_timeout;
2814
2815	/* backchannel */
2816	xprt_set_bound(xprt);
2817	xprt->bind_timeout = 0;
2818	xprt->reestablish_timeout = 0;
2819	xprt->idle_timeout = 0;
2820
2821	xprt->ops = &bc_tcp_ops;
2822
2823	switch (addr->sa_family) {
2824	case AF_INET:
2825		xs_format_peer_addresses(xprt, "tcp",
2826					 RPCBIND_NETID_TCP);
2827		break;
2828	case AF_INET6:
2829		xs_format_peer_addresses(xprt, "tcp",
2830				   RPCBIND_NETID_TCP6);
2831		break;
2832	default:
2833		ret = ERR_PTR(-EAFNOSUPPORT);
2834		goto out_err;
2835	}
2836
2837	dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2838			xprt->address_strings[RPC_DISPLAY_ADDR],
2839			xprt->address_strings[RPC_DISPLAY_PORT],
2840			xprt->address_strings[RPC_DISPLAY_PROTO]);
2841
2842	/*
2843	 * Once we've associated a backchannel xprt with a connection,
2844	 * we want to keep it around as long as long as the connection
2845	 * lasts, in case we need to start using it for a backchannel
2846	 * again; this reference won't be dropped until bc_xprt is
2847	 * destroyed.
2848	 */
2849	xprt_get(xprt);
2850	args->bc_xprt->xpt_bc_xprt = xprt;
2851	xprt->bc_xprt = args->bc_xprt;
2852	bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
2853	transport->sock = bc_sock->sk_sock;
2854	transport->inet = bc_sock->sk_sk;
2855
2856	/*
2857	 * Since we don't want connections for the backchannel, we set
2858	 * the xprt status to connected
2859	 */
2860	xprt_set_connected(xprt);
2861
2862
2863	if (try_module_get(THIS_MODULE))
2864		return xprt;
2865	xprt_put(xprt);
2866	ret = ERR_PTR(-EINVAL);
2867out_err:
2868	xprt_free(xprt);
2869	return ret;
2870}
2871
2872static struct xprt_class	xs_local_transport = {
2873	.list		= LIST_HEAD_INIT(xs_local_transport.list),
2874	.name		= "named UNIX socket",
2875	.owner		= THIS_MODULE,
2876	.ident		= XPRT_TRANSPORT_LOCAL,
2877	.setup		= xs_setup_local,
2878};
2879
2880static struct xprt_class	xs_udp_transport = {
2881	.list		= LIST_HEAD_INIT(xs_udp_transport.list),
2882	.name		= "udp",
2883	.owner		= THIS_MODULE,
2884	.ident		= XPRT_TRANSPORT_UDP,
2885	.setup		= xs_setup_udp,
2886};
2887
2888static struct xprt_class	xs_tcp_transport = {
2889	.list		= LIST_HEAD_INIT(xs_tcp_transport.list),
2890	.name		= "tcp",
2891	.owner		= THIS_MODULE,
2892	.ident		= XPRT_TRANSPORT_TCP,
2893	.setup		= xs_setup_tcp,
2894};
2895
2896static struct xprt_class	xs_bc_tcp_transport = {
2897	.list		= LIST_HEAD_INIT(xs_bc_tcp_transport.list),
2898	.name		= "tcp NFSv4.1 backchannel",
2899	.owner		= THIS_MODULE,
2900	.ident		= XPRT_TRANSPORT_BC_TCP,
2901	.setup		= xs_setup_bc_tcp,
2902};
2903
2904/**
2905 * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
2906 *
2907 */
2908int init_socket_xprt(void)
2909{
2910#ifdef RPC_DEBUG
2911	if (!sunrpc_table_header)
2912		sunrpc_table_header = register_sysctl_table(sunrpc_table);
2913#endif
2914
2915	xprt_register_transport(&xs_local_transport);
2916	xprt_register_transport(&xs_udp_transport);
2917	xprt_register_transport(&xs_tcp_transport);
2918	xprt_register_transport(&xs_bc_tcp_transport);
2919
2920	return 0;
2921}
2922
2923/**
2924 * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
2925 *
2926 */
2927void cleanup_socket_xprt(void)
2928{
2929#ifdef RPC_DEBUG
2930	if (sunrpc_table_header) {
2931		unregister_sysctl_table(sunrpc_table_header);
2932		sunrpc_table_header = NULL;
2933	}
2934#endif
2935
2936	xprt_unregister_transport(&xs_local_transport);
2937	xprt_unregister_transport(&xs_udp_transport);
2938	xprt_unregister_transport(&xs_tcp_transport);
2939	xprt_unregister_transport(&xs_bc_tcp_transport);
2940}
2941
2942static int param_set_uint_minmax(const char *val,
2943		const struct kernel_param *kp,
2944		unsigned int min, unsigned int max)
2945{
2946	unsigned long num;
2947	int ret;
2948
2949	if (!val)
2950		return -EINVAL;
2951	ret = strict_strtoul(val, 0, &num);
2952	if (ret == -EINVAL || num < min || num > max)
2953		return -EINVAL;
2954	*((unsigned int *)kp->arg) = num;
2955	return 0;
2956}
2957
2958static int param_set_portnr(const char *val, const struct kernel_param *kp)
2959{
2960	return param_set_uint_minmax(val, kp,
2961			RPC_MIN_RESVPORT,
2962			RPC_MAX_RESVPORT);
2963}
2964
2965static struct kernel_param_ops param_ops_portnr = {
2966	.set = param_set_portnr,
2967	.get = param_get_uint,
2968};
2969
2970#define param_check_portnr(name, p) \
2971	__param_check(name, p, unsigned int);
2972
2973module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
2974module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
2975
2976static int param_set_slot_table_size(const char *val,
2977				     const struct kernel_param *kp)
2978{
2979	return param_set_uint_minmax(val, kp,
2980			RPC_MIN_SLOT_TABLE,
2981			RPC_MAX_SLOT_TABLE);
2982}
2983
2984static struct kernel_param_ops param_ops_slot_table_size = {
2985	.set = param_set_slot_table_size,
2986	.get = param_get_uint,
2987};
2988
2989#define param_check_slot_table_size(name, p) \
2990	__param_check(name, p, unsigned int);
2991
2992static int param_set_max_slot_table_size(const char *val,
2993				     const struct kernel_param *kp)
2994{
2995	return param_set_uint_minmax(val, kp,
2996			RPC_MIN_SLOT_TABLE,
2997			RPC_MAX_SLOT_TABLE_LIMIT);
2998}
2999
3000static struct kernel_param_ops param_ops_max_slot_table_size = {
3001	.set = param_set_max_slot_table_size,
3002	.get = param_get_uint,
3003};
3004
3005#define param_check_max_slot_table_size(name, p) \
3006	__param_check(name, p, unsigned int);
3007
3008module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3009		   slot_table_size, 0644);
3010module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3011		   max_slot_table_size, 0644);
3012module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3013		   slot_table_size, 0644);
3014