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author	Boris Brezillon <boris.brezillon@free-electrons.com>	2015-01-14 11:22:02 -0500
committer	Nicolas Ferre <nicolas.ferre@atmel.com>	2015-01-15 08:52:07 -0500
commit	f0bceab4e3b528e799aba8fda8d2936fcfd41f1f (patch)
tree	7093239025b63922fa6efff9f10834c9fcb8912d /tools/perf/scripts/python/net_dropmonitor.py
parent	422cde259ab62fcddcb3e50f44f761cf26982c1e (diff)

usb: gadget: at91_udc: Rework for multi-platform kernel support

cpu_is_at91xxx are a set of macros defined in mach/cpu.h and are here used to detect the SoC we are booting on. Use compatible string + a caps structure to replace those cpu_is_xxx tests. Remove all mach and asm headers (which are now unused). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Acked-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>

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0 files changed, 0 insertions, 0 deletions

2006-12-07 11:39:27 -0500 [PATCH] Add include/linux/freezer.h and move definitions from sched.h' href='/cgit/cgit.cgi/litmus-rt-imx6.git/commit/net/sunrpc/svcsock.c?id=7dfb71030f7636a0d65200158113c37764552f93'>7dfb71030f76

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/*
 * linux/net/sunrpc/svcsock.c
 *
 * These are the RPC server socket internals.
 *
 * The server scheduling algorithm does not always distribute the load
 * evenly when servicing a single client. May need to modify the
 * svc_xprt_enqueue procedure...
 *
 * TCP support is largely untested and may be a little slow. The problem
 * is that we currently do two separate recvfrom's, one for the 4-byte
 * record length, and the second for the actual record. This could possibly
 * be improved by always reading a minimum size of around 100 bytes and
 * tucking any superfluous bytes away in a temporary store. Still, that
 * leaves write requests out in the rain. An alternative may be to peek at
 * the first skb in the queue, and if it matches the next TCP sequence
 * number, to extract the record marker. Yuck.
 *
 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
 */

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/fcntl.h>
#include <linux/net.h>
#include <linux/in.h>
#include <linux/inet.h>
#include <linux/udp.h>
#include <linux/tcp.h>
#include <linux/unistd.h>
#include <linux/slab.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/file.h>
#include <linux/freezer.h>
#include <net/sock.h>
#include <net/checksum.h>
#include <net/ip.h>
#include <net/ipv6.h>
#include <net/tcp.h>
#include <net/tcp_states.h>
#include <asm/uaccess.h>
#include <asm/ioctls.h>
#include <trace/events/skb.h>

#include <linux/sunrpc/types.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/xdr.h>
#include <linux/sunrpc/msg_prot.h>
#include <linux/sunrpc/svcsock.h>
#include <linux/sunrpc/stats.h>
#include <linux/sunrpc/xprt.h>

#include "sunrpc.h"

#define RPCDBG_FACILITY	RPCDBG_SVCXPRT


static struct svc_sock *svc_setup_socket(struct svc_serv *, struct socket *,
					 int flags);
static void		svc_udp_data_ready(struct sock *, int);
static int		svc_udp_recvfrom(struct svc_rqst *);
static int		svc_udp_sendto(struct svc_rqst *);
static void		svc_sock_detach(struct svc_xprt *);
static void		svc_tcp_sock_detach(struct svc_xprt *);
static void		svc_sock_free(struct svc_xprt *);

static struct svc_xprt *svc_create_socket(struct svc_serv *, int,
					  struct net *, struct sockaddr *,
					  int, int);
#if defined(CONFIG_SUNRPC_BACKCHANNEL)
static struct svc_xprt *svc_bc_create_socket(struct svc_serv *, int,
					     struct net *, struct sockaddr *,
					     int, int);
static void svc_bc_sock_free(struct svc_xprt *xprt);
#endif /* CONFIG_SUNRPC_BACKCHANNEL */

#ifdef CONFIG_DEBUG_LOCK_ALLOC
static struct lock_class_key svc_key[2];
static struct lock_class_key svc_slock_key[2];

static void svc_reclassify_socket(struct socket *sock)
{
	struct sock *sk = sock->sk;

	WARN_ON_ONCE(sock_owned_by_user(sk));
	if (sock_owned_by_user(sk))
		return;

	switch (sk->sk_family) {
	case AF_INET:
		sock_lock_init_class_and_name(sk, "slock-AF_INET-NFSD",
					      &svc_slock_key[0],
					      "sk_xprt.xpt_lock-AF_INET-NFSD",
					      &svc_key[0]);
		break;

	case AF_INET6:
		sock_lock_init_class_and_name(sk, "slock-AF_INET6-NFSD",
					      &svc_slock_key[1],
					      "sk_xprt.xpt_lock-AF_INET6-NFSD",
					      &svc_key[1]);
		break;

	default:
		BUG();
	}
}
#else
static void svc_reclassify_socket(struct socket *sock)
{
}
#endif

/*
 * Release an skbuff after use
 */
static void svc_release_skb(struct svc_rqst *rqstp)
{
	struct sk_buff *skb = rqstp->rq_xprt_ctxt;

	if (skb) {
		struct svc_sock *svsk =
			container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
		rqstp->rq_xprt_ctxt = NULL;

		dprintk("svc: service %p, releasing skb %p\n", rqstp, skb);
		skb_free_datagram_locked(svsk->sk_sk, skb);
	}
}

union svc_pktinfo_u {
	struct in_pktinfo pkti;
	struct in6_pktinfo pkti6;
};
#define SVC_PKTINFO_SPACE \
	CMSG_SPACE(sizeof(union svc_pktinfo_u))

static void svc_set_cmsg_data(struct svc_rqst *rqstp, struct cmsghdr *cmh)
{
	struct svc_sock *svsk =
		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
	switch (svsk->sk_sk->sk_family) {
	case AF_INET: {
			struct in_pktinfo *pki = CMSG_DATA(cmh);

			cmh->cmsg_level = SOL_IP;
			cmh->cmsg_type = IP_PKTINFO;
			pki->ipi_ifindex = 0;
			pki->ipi_spec_dst.s_addr =
				 svc_daddr_in(rqstp)->sin_addr.s_addr;
			cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
		}
		break;

	case AF_INET6: {
			struct in6_pktinfo *pki = CMSG_DATA(cmh);
			struct sockaddr_in6 *daddr = svc_daddr_in6(rqstp);

			cmh->cmsg_level = SOL_IPV6;
			cmh->cmsg_type = IPV6_PKTINFO;
			pki->ipi6_ifindex = daddr->sin6_scope_id;
			pki->ipi6_addr = daddr->sin6_addr;
			cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
		}
		break;
	}
}

/*
 * send routine intended to be shared by the fore- and back-channel
 */
int svc_send_common(struct socket *sock, struct xdr_buf *xdr,
		    struct page *headpage, unsigned long headoffset,
		    struct page *tailpage, unsigned long tailoffset)
{
	int		result;
	int		size;
	struct page	**ppage = xdr->pages;
	size_t		base = xdr->page_base;
	unsigned int	pglen = xdr->page_len;
	unsigned int	flags = MSG_MORE;
	int		slen;
	int		len = 0;

	slen = xdr->len;

	/* send head */
	if (slen == xdr->head[0].iov_len)
		flags = 0;
	len = kernel_sendpage(sock, headpage, headoffset,
				  xdr->head[0].iov_len, flags);
	if (len != xdr->head[0].iov_len)
		goto out;
	slen -= xdr->head[0].iov_len;
	if (slen == 0)
		goto out;

	/* send page data */
	size = PAGE_SIZE - base < pglen ? PAGE_SIZE - base : pglen;
	while (pglen > 0) {
		if (slen == size)
			flags = 0;
		result = kernel_sendpage(sock, *ppage, base, size, flags);
		if (result > 0)
			len += result;
		if (result != size)
			goto out;
		slen -= size;
		pglen -= size;
		size = PAGE_SIZE < pglen ? PAGE_SIZE : pglen;
		base = 0;
		ppage++;
	}

	/* send tail */
	if (xdr->tail[0].iov_len) {
		result = kernel_sendpage(sock, tailpage, tailoffset,
				   xdr->tail[0].iov_len, 0);
		if (result > 0)
			len += result;
	}

out:
	return len;
}


/*
 * Generic sendto routine
 */
static int svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr)
{
	struct svc_sock	*svsk =
		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
	struct socket	*sock = svsk->sk_sock;
	union {
		struct cmsghdr	hdr;
		long		all[SVC_PKTINFO_SPACE / sizeof(long)];
	} buffer;
	struct cmsghdr *cmh = &buffer.hdr;
	int		len = 0;
	unsigned long tailoff;
	unsigned long headoff;
	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);

	if (rqstp->rq_prot == IPPROTO_UDP) {
		struct msghdr msg = {
			.msg_name	= &rqstp->rq_addr,
			.msg_namelen	= rqstp->rq_addrlen,
			.msg_control	= cmh,
			.msg_controllen	= sizeof(buffer),
			.msg_flags	= MSG_MORE,
		};

		svc_set_cmsg_data(rqstp, cmh);

		if (sock_sendmsg(sock, &msg, 0) < 0)
			goto out;
	}

	tailoff = ((unsigned long)xdr->tail[0].iov_base) & (PAGE_SIZE-1);
	headoff = 0;
	len = svc_send_common(sock, xdr, rqstp->rq_respages[0], headoff,
			       rqstp->rq_respages[0], tailoff);

out:
	dprintk("svc: socket %p sendto([%p %Zu... ], %d) = %d (addr %s)\n",
		svsk, xdr->head[0].iov_base, xdr->head[0].iov_len,
		xdr->len, len, svc_print_addr(rqstp, buf, sizeof(buf)));

	return len;
}

/*
 * Report socket names for nfsdfs
 */
static int svc_one_sock_name(struct svc_sock *svsk, char *buf, int remaining)
{
	const struct sock *sk = svsk->sk_sk;
	const char *proto_name = sk->sk_protocol == IPPROTO_UDP ?
							"udp" : "tcp";
	int len;

	switch (sk->sk_family) {
	case PF_INET:
		len = snprintf(buf, remaining, "ipv4 %s %pI4 %d\n",
				proto_name,
				&inet_sk(sk)->inet_rcv_saddr,
				inet_sk(sk)->inet_num);
		break;
	case PF_INET6:
		len = snprintf(buf, remaining, "ipv6 %s %pI6 %d\n",
				proto_name,
				&inet6_sk(sk)->rcv_saddr,
				inet_sk(sk)->inet_num);
		break;
	default:
		len = snprintf(buf, remaining, "*unknown-%d*\n",
				sk->sk_family);
	}

	if (len >= remaining) {
		*buf = '\0';
		return -ENAMETOOLONG;
	}
	return len;
}

/*
 * Check input queue length
 */
static int svc_recv_available(struct svc_sock *svsk)
{
	struct socket	*sock = svsk->sk_sock;
	int		avail, err;

	err = kernel_sock_ioctl(sock, TIOCINQ, (unsigned long) &avail);

	return (err >= 0)? avail : err;
}

/*
 * Generic recvfrom routine.
 */
static int svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr,
			int buflen)
{
	struct svc_sock *svsk =
		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
	struct msghdr msg = {
		.msg_flags	= MSG_DONTWAIT,
	};
	int len;

	rqstp->rq_xprt_hlen = 0;

	len = kernel_recvmsg(svsk->sk_sock, &msg, iov, nr, buflen,
				msg.msg_flags);

	dprintk("svc: socket %p recvfrom(%p, %Zu) = %d\n",
		svsk, iov[0].iov_base, iov[0].iov_len, len);
	return len;
}

static int svc_partial_recvfrom(struct svc_rqst *rqstp,
				struct kvec *iov, int nr,
				int buflen, unsigned int base)
{
	size_t save_iovlen;
	void *save_iovbase;
	unsigned int i;
	int ret;

	if (base == 0)
		return svc_recvfrom(rqstp, iov, nr, buflen);

	for (i = 0; i < nr; i++) {
		if (iov[i].iov_len > base)
			break;
		base -= iov[i].iov_len;
	}
	save_iovlen = iov[i].iov_len;
	save_iovbase = iov[i].iov_base;
	iov[i].iov_len -= base;
	iov[i].iov_base += base;
	ret = svc_recvfrom(rqstp, &iov[i], nr - i, buflen);
	iov[i].iov_len = save_iovlen;
	iov[i].iov_base = save_iovbase;
	return ret;
}

/*
 * Set socket snd and rcv buffer lengths
 */
static void svc_sock_setbufsize(struct socket *sock, unsigned int snd,
				unsigned int rcv)
{
#if 0
	mm_segment_t	oldfs;
	oldfs = get_fs(); set_fs(KERNEL_DS);
	sock_setsockopt(sock, SOL_SOCKET, SO_SNDBUF,
			(char*)&snd, sizeof(snd));
	sock_setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
			(char*)&rcv, sizeof(rcv));
#else
	/* sock_setsockopt limits use to sysctl_?mem_max,
	 * which isn't acceptable.  Until that is made conditional
	 * on not having CAP_SYS_RESOURCE or similar, we go direct...
	 * DaveM said I could!
	 */
	lock_sock(sock->sk);
	sock->sk->sk_sndbuf = snd * 2;
	sock->sk->sk_rcvbuf = rcv * 2;
	sock->sk->sk_write_space(sock->sk);
	release_sock(sock->sk);
#endif
}
/*
 * INET callback when data has been received on the socket.
 */
static void svc_udp_data_ready(struct sock *sk, int count)
{
	struct svc_sock	*svsk = (struct svc_sock *)sk->sk_user_data;
	wait_queue_head_t *wq = sk_sleep(sk);

	if (svsk) {
		dprintk("svc: socket %p(inet %p), count=%d, busy=%d\n",
			svsk, sk, count,
			test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags));
		set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
		svc_xprt_enqueue(&svsk->sk_xprt);
	}
	if (wq && waitqueue_active(wq))
		wake_up_interruptible(wq);
}

/*
 * INET callback when space is newly available on the socket.
 */
static void svc_write_space(struct sock *sk)
{
	struct svc_sock	*svsk = (struct svc_sock *)(sk->sk_user_data);
	wait_queue_head_t *wq = sk_sleep(sk);

	if (svsk) {
		dprintk("svc: socket %p(inet %p), write_space busy=%d\n",
			svsk, sk, test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags));
		svc_xprt_enqueue(&svsk->sk_xprt);
	}

	if (wq && waitqueue_active(wq)) {
		dprintk("RPC svc_write_space: someone sleeping on %p\n",
		       svsk);
		wake_up_interruptible(wq);
	}
}

static void svc_tcp_write_space(struct sock *sk)
{
	struct socket *sock = sk->sk_socket;

	if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) && sock)
		clear_bit(SOCK_NOSPACE, &sock->flags);
	svc_write_space(sk);
}

/*
 * See net/ipv6/ip_sockglue.c : ip_cmsg_recv_pktinfo
 */
static int svc_udp_get_dest_address4(struct svc_rqst *rqstp,
				     struct cmsghdr *cmh)
{
	struct in_pktinfo *pki = CMSG_DATA(cmh);
	struct sockaddr_in *daddr = svc_daddr_in(rqstp);

	if (cmh->cmsg_type != IP_PKTINFO)
		return 0;

	daddr->sin_family = AF_INET;
	daddr->sin_addr.s_addr = pki->ipi_spec_dst.s_addr;
	return 1;
}

/*
 * See net/ipv6/datagram.c : ip6_datagram_recv_ctl
 */
static int svc_udp_get_dest_address6(struct svc_rqst *rqstp,
				     struct cmsghdr *cmh)
{
	struct in6_pktinfo *pki = CMSG_DATA(cmh);
	struct sockaddr_in6 *daddr = svc_daddr_in6(rqstp);

	if (cmh->cmsg_type != IPV6_PKTINFO)
		return 0;

	daddr->sin6_family = AF_INET6;
	daddr->sin6_addr = pki->ipi6_addr;
	daddr->sin6_scope_id = pki->ipi6_ifindex;
	return 1;
}

/*
 * Copy the UDP datagram's destination address to the rqstp structure.
 * The 'destination' address in this case is the address to which the
 * peer sent the datagram, i.e. our local address. For multihomed
 * hosts, this can change from msg to msg. Note that only the IP
 * address changes, the port number should remain the same.
 */
static int svc_udp_get_dest_address(struct svc_rqst *rqstp,
				    struct cmsghdr *cmh)
{
	switch (cmh->cmsg_level) {
	case SOL_IP:
		return svc_udp_get_dest_address4(rqstp, cmh);
	case SOL_IPV6:
		return svc_udp_get_dest_address6(rqstp, cmh);
	}

	return 0;
}

/*
 * Receive a datagram from a UDP socket.
 */
static int svc_udp_recvfrom(struct svc_rqst *rqstp)
{
	struct svc_sock	*svsk =
		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
	struct svc_serv	*serv = svsk->sk_xprt.xpt_server;
	struct sk_buff	*skb;
	union {
		struct cmsghdr	hdr;
		long		all[SVC_PKTINFO_SPACE / sizeof(long)];
	} buffer;
	struct cmsghdr *cmh = &buffer.hdr;
	struct msghdr msg = {
		.msg_name = svc_addr(rqstp),
		.msg_control = cmh,
		.msg_controllen = sizeof(buffer),
		.msg_flags = MSG_DONTWAIT,
	};
	size_t len;
	int err;

	if (test_and_clear_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags))
	    /* udp sockets need large rcvbuf as all pending
	     * requests are still in that buffer.  sndbuf must
	     * also be large enough that there is enough space
	     * for one reply per thread.  We count all threads
	     * rather than threads in a particular pool, which
	     * provides an upper bound on the number of threads
	     * which will access the socket.
	     */
	    svc_sock_setbufsize(svsk->sk_sock,
				(serv->sv_nrthreads+3) * serv->sv_max_mesg,
				(serv->sv_nrthreads+3) * serv->sv_max_mesg);

	clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
	skb = NULL;
	err = kernel_recvmsg(svsk->sk_sock, &msg, NULL,
			     0, 0, MSG_PEEK | MSG_DONTWAIT);
	if (err >= 0)
		skb = skb_recv_datagram(svsk->sk_sk, 0, 1, &err);

	if (skb == NULL) {
		if (err != -EAGAIN) {
			/* possibly an icmp error */
			dprintk("svc: recvfrom returned error %d\n", -err);
			set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
		}
		return 0;
	}
	len = svc_addr_len(svc_addr(rqstp));
	rqstp->rq_addrlen = len;
	if (skb->tstamp.tv64 == 0) {
		skb->tstamp = ktime_get_real();
		/* Don't enable netstamp, sunrpc doesn't
		   need that much accuracy */
	}
	svsk->sk_sk->sk_stamp = skb->tstamp;
	set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); /* there may be more data... */

	len  = skb->len - sizeof(struct udphdr);
	rqstp->rq_arg.len = len;

	rqstp->rq_prot = IPPROTO_UDP;

	if (!svc_udp_get_dest_address(rqstp, cmh)) {
		net_warn_ratelimited("svc: received unknown control message %d/%d; dropping RPC reply datagram\n",
				     cmh->cmsg_level, cmh->cmsg_type);
		goto out_free;
	}
	rqstp->rq_daddrlen = svc_addr_len(svc_daddr(rqstp));

	if (skb_is_nonlinear(skb)) {
		/* we have to copy */
		local_bh_disable();
		if (csum_partial_copy_to_xdr(&rqstp->rq_arg, skb)) {
			local_bh_enable();
			/* checksum error */
			goto out_free;
		}
		local_bh_enable();
		skb_free_datagram_locked(svsk->sk_sk, skb);
	} else {
		/* we can use it in-place */
		rqstp->rq_arg.head[0].iov_base = skb->data +
			sizeof(struct udphdr);
		rqstp->rq_arg.head[0].iov_len = len;
		if (skb_checksum_complete(skb))
			goto out_free;
		rqstp->rq_xprt_ctxt = skb;
	}

	rqstp->rq_arg.page_base = 0;
	if (len <= rqstp->rq_arg.head[0].iov_len) {
		rqstp->rq_arg.head[0].iov_len = len;
		rqstp->rq_arg.page_len = 0;
		rqstp->rq_respages = rqstp->rq_pages+1;
	} else {
		rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len;
		rqstp->rq_respages = rqstp->rq_pages + 1 +
			DIV_ROUND_UP(rqstp->rq_arg.page_len, PAGE_SIZE);
	}
	rqstp->rq_next_page = rqstp->rq_respages+1;

	if (serv->sv_stats)
		serv->sv_stats->netudpcnt++;

	return len;
out_free:
	trace_kfree_skb(skb, svc_udp_recvfrom);
	skb_free_datagram_locked(svsk->sk_sk, skb);
	return 0;
}

static int
svc_udp_sendto(struct svc_rqst *rqstp)
{
	int		error;

	error = svc_sendto(rqstp, &rqstp->rq_res);
	if (error == -ECONNREFUSED)
		/* ICMP error on earlier request. */
		error = svc_sendto(rqstp, &rqstp->rq_res);

	return error;
}

static void svc_udp_prep_reply_hdr(struct svc_rqst *rqstp)
{
}

static int svc_udp_has_wspace(struct svc_xprt *xprt)
{
	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
	struct svc_serv	*serv = xprt->xpt_server;
	unsigned long required;

	/*
	 * Set the SOCK_NOSPACE flag before checking the available
	 * sock space.
	 */
	set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
	required = atomic_read(&svsk->sk_xprt.xpt_reserved) + serv->sv_max_mesg;
	if (required*2 > sock_wspace(svsk->sk_sk))
		return 0;
	clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
	return 1;
}

static struct svc_xprt *svc_udp_accept(struct svc_xprt *xprt)
{
	BUG();
	return NULL;
}

static struct svc_xprt *svc_udp_create(struct svc_serv *serv,
				       struct net *net,
				       struct sockaddr *sa, int salen,
				       int flags)
{
	return svc_create_socket(serv, IPPROTO_UDP, net, sa, salen, flags);
}

static struct svc_xprt_ops svc_udp_ops = {
	.xpo_create = svc_udp_create,
	.xpo_recvfrom = svc_udp_recvfrom,
	.xpo_sendto = svc_udp_sendto,
	.xpo_release_rqst = svc_release_skb,
	.xpo_detach = svc_sock_detach,
	.xpo_free = svc_sock_free,
	.xpo_prep_reply_hdr = svc_udp_prep_reply_hdr,
	.xpo_has_wspace = svc_udp_has_wspace,
	.xpo_accept = svc_udp_accept,
};

static struct svc_xprt_class svc_udp_class = {
	.xcl_name = "udp",
	.xcl_owner = THIS_MODULE,
	.xcl_ops = &svc_udp_ops,
	.xcl_max_payload = RPCSVC_MAXPAYLOAD_UDP,
};

static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv)
{
	int err, level, optname, one = 1;

	svc_xprt_init(sock_net(svsk->sk_sock->sk), &svc_udp_class,
		      &svsk->sk_xprt, serv);
	clear_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
	svsk->sk_sk->sk_data_ready = svc_udp_data_ready;
	svsk->sk_sk->sk_write_space = svc_write_space;

	/* initialise setting must have enough space to
	 * receive and respond to one request.
	 * svc_udp_recvfrom will re-adjust if necessary
	 */
	svc_sock_setbufsize(svsk->sk_sock,
			    3 * svsk->sk_xprt.xpt_server->sv_max_mesg,
			    3 * svsk->sk_xprt.xpt_server->sv_max_mesg);

	/* data might have come in before data_ready set up */
	set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
	set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);

	/* make sure we get destination address info */
	switch (svsk->sk_sk->sk_family) {
	case AF_INET:
		level = SOL_IP;
		optname = IP_PKTINFO;
		break;
	case AF_INET6:
		level = SOL_IPV6;
		optname = IPV6_RECVPKTINFO;
		break;
	default:
		BUG();
	}
	err = kernel_setsockopt(svsk->sk_sock, level, optname,
					(char *)&one, sizeof(one));
	dprintk("svc: kernel_setsockopt returned %d\n", err);
}

/*
 * A data_ready event on a listening socket means there's a connection
 * pending. Do not use state_change as a substitute for it.
 */
static void svc_tcp_listen_data_ready(struct sock *sk, int count_unused)
{
	struct svc_sock	*svsk = (struct svc_sock *)sk->sk_user_data;
	wait_queue_head_t *wq;

	dprintk("svc: socket %p TCP (listen) state change %d\n",
		sk, sk->sk_state);

	/*
	 * This callback may called twice when a new connection
	 * is established as a child socket inherits everything
	 * from a parent LISTEN socket.
	 * 1) data_ready method of the parent socket will be called
	 *    when one of child sockets become ESTABLISHED.
	 * 2) data_ready method of the child socket may be called
	 *    when it receives data before the socket is accepted.
	 * In case of 2, we should ignore it silently.
	 */
	if (sk->sk_state == TCP_LISTEN) {
		if (svsk) {
			set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
			svc_xprt_enqueue(&svsk->sk_xprt);
		} else
			printk("svc: socket %p: no user data\n", sk);
	}

	wq = sk_sleep(sk);
	if (wq && waitqueue_active(wq))
		wake_up_interruptible_all(wq);
}

/*
 * A state change on a connected socket means it's dying or dead.
 */
static void svc_tcp_state_change(struct sock *sk)
{
	struct svc_sock	*svsk = (struct svc_sock *)sk->sk_user_data;
	wait_queue_head_t *wq = sk_sleep(sk);

	dprintk("svc: socket %p TCP (connected) state change %d (svsk %p)\n",
		sk, sk->sk_state, sk->sk_user_data);

	if (!svsk)
		printk("svc: socket %p: no user data\n", sk);
	else {
		set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
		svc_xprt_enqueue(&svsk->sk_xprt);
	}
	if (wq && waitqueue_active(wq))
		wake_up_interruptible_all(wq);
}

static void svc_tcp_data_ready(struct sock *sk, int count)
{
	struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
	wait_queue_head_t *wq = sk_sleep(sk);

	dprintk("svc: socket %p TCP data ready (svsk %p)\n",
		sk, sk->sk_user_data);
	if (svsk) {
		set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
		svc_xprt_enqueue(&svsk->sk_xprt);
	}
	if (wq && waitqueue_active(wq))
		wake_up_interruptible(wq);
}

/*
 * Accept a TCP connection
 */
static struct svc_xprt *svc_tcp_accept(struct svc_xprt *xprt)
{
	struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);


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