Make socantsendmore() available which required sys/aio.h

1 files changed, 1056 insertions, 0 deletions

diff --git a/freebsd/kern/uipc_sockbuf.c b/freebsd/kern/uipc_sockbuf.c
new file mode 100644
index 00000000..3e331ee0
--- /dev/null
+++ b/freebsd/kern/uipc_sockbuf.c
@@ -0,0 +1,1056 @@
+#include <freebsd/machine/rtems-bsd-config.h>
+
+/*-
+ * Copyright (c) 1982, 1986, 1988, 1990, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	@(#)uipc_socket2.c	8.1 (Berkeley) 6/10/93
+ */
+
+#include <freebsd/sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <freebsd/local/opt_param.h>
+
+#include <freebsd/sys/param.h>
+#include <freebsd/sys/aio.h> /* for aio_swake proto */
+#include <freebsd/sys/kernel.h>
+#include <freebsd/sys/lock.h>
+#include <freebsd/sys/mbuf.h>
+#include <freebsd/sys/mutex.h>
+#include <freebsd/sys/proc.h>
+#include <freebsd/sys/protosw.h>
+#include <freebsd/sys/resourcevar.h>
+#include <freebsd/sys/signalvar.h>
+#include <freebsd/sys/socket.h>
+#include <freebsd/sys/socketvar.h>
+#include <freebsd/sys/sx.h>
+#include <freebsd/sys/sysctl.h>
+
+/*
+ * Function pointer set by the AIO routines so that the socket buffer code
+ * can call back into the AIO module if it is loaded.
+ */
+void	(*aio_swake)(struct socket *, struct sockbuf *);
+
+/*
+ * Primitive routines for operating on socket buffers
+ */
+
+u_long	sb_max = SB_MAX;
+u_long sb_max_adj =
+       SB_MAX * MCLBYTES / (MSIZE + MCLBYTES); /* adjusted sb_max */
+
+static	u_long sb_efficiency = 8;	/* parameter for sbreserve() */
+
+static void	sbdrop_internal(struct sockbuf *sb, int len);
+static void	sbflush_internal(struct sockbuf *sb);
+
+/*
+ * Socantsendmore indicates that no more data will be sent on the socket; it
+ * would normally be applied to a socket when the user informs the system
+ * that no more data is to be sent, by the protocol code (in case
+ * PRU_SHUTDOWN).  Socantrcvmore indicates that no more data will be
+ * received, and will normally be applied to the socket by a protocol when it
+ * detects that the peer will send no more data.  Data queued for reading in
+ * the socket may yet be read.
+ */
+void
+socantsendmore_locked(struct socket *so)
+{
+
+	SOCKBUF_LOCK_ASSERT(&so->so_snd);
+
+	so->so_snd.sb_state |= SBS_CANTSENDMORE;
+	sowwakeup_locked(so);
+	mtx_assert(SOCKBUF_MTX(&so->so_snd), MA_NOTOWNED);
+}
+
+void
+socantsendmore(struct socket *so)
+{
+
+	SOCKBUF_LOCK(&so->so_snd);
+	socantsendmore_locked(so);
+	mtx_assert(SOCKBUF_MTX(&so->so_snd), MA_NOTOWNED);
+}
+
+void
+socantrcvmore_locked(struct socket *so)
+{
+
+	SOCKBUF_LOCK_ASSERT(&so->so_rcv);
+
+	so->so_rcv.sb_state |= SBS_CANTRCVMORE;
+	sorwakeup_locked(so);
+	mtx_assert(SOCKBUF_MTX(&so->so_rcv), MA_NOTOWNED);
+}
+
+void
+socantrcvmore(struct socket *so)
+{
+
+	SOCKBUF_LOCK(&so->so_rcv);
+	socantrcvmore_locked(so);
+	mtx_assert(SOCKBUF_MTX(&so->so_rcv), MA_NOTOWNED);
+}
+
+/*
+ * Wait for data to arrive at/drain from a socket buffer.
+ */
+int
+sbwait(struct sockbuf *sb)
+{
+
+	SOCKBUF_LOCK_ASSERT(sb);
+
+	sb->sb_flags |= SB_WAIT;
+	return (msleep(&sb->sb_cc, &sb->sb_mtx,
+	    (sb->sb_flags & SB_NOINTR) ? PSOCK : PSOCK | PCATCH, "sbwait",
+	    sb->sb_timeo));
+}
+
+int
+sblock(struct sockbuf *sb, int flags)
+{
+
+	KASSERT((flags & SBL_VALID) == flags,
+	    ("sblock: flags invalid (0x%x)", flags));
+
+	if (flags & SBL_WAIT) {
+		if ((sb->sb_flags & SB_NOINTR) ||
+		    (flags & SBL_NOINTR)) {
+			sx_xlock(&sb->sb_sx);
+			return (0);
+		}
+		return (sx_xlock_sig(&sb->sb_sx));
+	} else {
+		if (sx_try_xlock(&sb->sb_sx) == 0)
+			return (EWOULDBLOCK);
+		return (0);
+	}
+}
+
+void
+sbunlock(struct sockbuf *sb)
+{
+
+	sx_xunlock(&sb->sb_sx);
+}
+
+/*
+ * Wakeup processes waiting on a socket buffer.  Do asynchronous notification
+ * via SIGIO if the socket has the SS_ASYNC flag set.
+ *
+ * Called with the socket buffer lock held; will release the lock by the end
+ * of the function.  This allows the caller to acquire the socket buffer lock
+ * while testing for the need for various sorts of wakeup and hold it through
+ * to the point where it's no longer required.  We currently hold the lock
+ * through calls out to other subsystems (with the exception of kqueue), and
+ * then release it to avoid lock order issues.  It's not clear that's
+ * correct.
+ */
+void
+sowakeup(struct socket *so, struct sockbuf *sb)
+{
+	int ret;
+
+	SOCKBUF_LOCK_ASSERT(sb);
+
+	selwakeuppri(&sb->sb_sel, PSOCK);
+	if (!SEL_WAITING(&sb->sb_sel))
+		sb->sb_flags &= ~SB_SEL;
+	if (sb->sb_flags & SB_WAIT) {
+		sb->sb_flags &= ~SB_WAIT;
+		wakeup(&sb->sb_cc);
+	}
+	KNOTE_LOCKED(&sb->sb_sel.si_note, 0);
+	if (sb->sb_upcall != NULL) {
+		ret = sb->sb_upcall(so, sb->sb_upcallarg, M_DONTWAIT);
+		if (ret == SU_ISCONNECTED) {
+			KASSERT(sb == &so->so_rcv,
+			    ("SO_SND upcall returned SU_ISCONNECTED"));
+			soupcall_clear(so, SO_RCV);
+		}
+	} else
+		ret = SU_OK;
+	if (sb->sb_flags & SB_AIO)
+		aio_swake(so, sb);
+	SOCKBUF_UNLOCK(sb);
+	if (ret == SU_ISCONNECTED)
+		soisconnected(so);
+	if ((so->so_state & SS_ASYNC) && so->so_sigio != NULL)
+		pgsigio(&so->so_sigio, SIGIO, 0);
+	mtx_assert(SOCKBUF_MTX(sb), MA_NOTOWNED);
+}
+
+/*
+ * Socket buffer (struct sockbuf) utility routines.
+ *
+ * Each socket contains two socket buffers: one for sending data and one for
+ * receiving data.  Each buffer contains a queue of mbufs, information about
+ * the number of mbufs and amount of data in the queue, and other fields
+ * allowing select() statements and notification on data availability to be
+ * implemented.
+ *
+ * Data stored in a socket buffer is maintained as a list of records.  Each
+ * record is a list of mbufs chained together with the m_next field.  Records
+ * are chained together with the m_nextpkt field. The upper level routine
+ * soreceive() expects the following conventions to be observed when placing
+ * information in the receive buffer:
+ *
+ * 1. If the protocol requires each message be preceded by the sender's name,
+ *    then a record containing that name must be present before any
+ *    associated data (mbuf's must be of type MT_SONAME).
+ * 2. If the protocol supports the exchange of ``access rights'' (really just
+ *    additional data associated with the message), and there are ``rights''
+ *    to be received, then a record containing this data should be present
+ *    (mbuf's must be of type MT_RIGHTS).
+ * 3. If a name or rights record exists, then it must be followed by a data
+ *    record, perhaps of zero length.
+ *
+ * Before using a new socket structure it is first necessary to reserve
+ * buffer space to the socket, by calling sbreserve().  This should commit
+ * some of the available buffer space in the system buffer pool for the
+ * socket (currently, it does nothing but enforce limits).  The space should
+ * be released by calling sbrelease() when the socket is destroyed.
+ */
+int
+soreserve(struct socket *so, u_long sndcc, u_long rcvcc)
+{
+	struct thread *td = curthread;
+
+	SOCKBUF_LOCK(&so->so_snd);
+	SOCKBUF_LOCK(&so->so_rcv);
+	if (sbreserve_locked(&so->so_snd, sndcc, so, td) == 0)
+		goto bad;
+	if (sbreserve_locked(&so->so_rcv, rcvcc, so, td) == 0)
+		goto bad2;
+	if (so->so_rcv.sb_lowat == 0)
+		so->so_rcv.sb_lowat = 1;
+	if (so->so_snd.sb_lowat == 0)
+		so->so_snd.sb_lowat = MCLBYTES;
+	if (so->so_snd.sb_lowat > so->so_snd.sb_hiwat)
+		so->so_snd.sb_lowat = so->so_snd.sb_hiwat;
+	SOCKBUF_UNLOCK(&so->so_rcv);
+	SOCKBUF_UNLOCK(&so->so_snd);
+	return (0);
+bad2:
+	sbrelease_locked(&so->so_snd, so);
+bad:
+	SOCKBUF_UNLOCK(&so->so_rcv);
+	SOCKBUF_UNLOCK(&so->so_snd);
+	return (ENOBUFS);
+}
+
+static int
+sysctl_handle_sb_max(SYSCTL_HANDLER_ARGS)
+{
+	int error = 0;
+	u_long tmp_sb_max = sb_max;
+
+	error = sysctl_handle_long(oidp, &tmp_sb_max, arg2, req);
+	if (error || !req->newptr)
+		return (error);
+	if (tmp_sb_max < MSIZE + MCLBYTES)
+		return (EINVAL);
+	sb_max = tmp_sb_max;
+	sb_max_adj = (u_quad_t)sb_max * MCLBYTES / (MSIZE + MCLBYTES);
+	return (0);
+}
+	
+/*
+ * Allot mbufs to a sockbuf.  Attempt to scale mbmax so that mbcnt doesn't
+ * become limiting if buffering efficiency is near the normal case.
+ */
+int
+sbreserve_locked(struct sockbuf *sb, u_long cc, struct socket *so,
+    struct thread *td)
+{
+	rlim_t sbsize_limit;
+
+	SOCKBUF_LOCK_ASSERT(sb);
+
+	/*
+	 * When a thread is passed, we take into account the thread's socket
+	 * buffer size limit.  The caller will generally pass curthread, but
+	 * in the TCP input path, NULL will be passed to indicate that no
+	 * appropriate thread resource limits are available.  In that case,
+	 * we don't apply a process limit.
+	 */
+	if (cc > sb_max_adj)
+		return (0);
+	if (td != NULL) {
+		PROC_LOCK(td->td_proc);
+		sbsize_limit = lim_cur(td->td_proc, RLIMIT_SBSIZE);
+		PROC_UNLOCK(td->td_proc);
+	} else
+		sbsize_limit = RLIM_INFINITY;
+	if (!chgsbsize(so->so_cred->cr_uidinfo, &sb->sb_hiwat, cc,
+	    sbsize_limit))
+		return (0);
+	sb->sb_mbmax = min(cc * sb_efficiency, sb_max);
+	if (sb->sb_lowat > sb->sb_hiwat)
+		sb->sb_lowat = sb->sb_hiwat;
+	return (1);
+}
+
+int
+sbreserve(struct sockbuf *sb, u_long cc, struct socket *so, 
+    struct thread *td)
+{
+	int error;
+
+	SOCKBUF_LOCK(sb);
+	error = sbreserve_locked(sb, cc, so, td);
+	SOCKBUF_UNLOCK(sb);
+	return (error);
+}
+
+/*
+ * Free mbufs held by a socket, and reserved mbuf space.
+ */
+void
+sbrelease_internal(struct sockbuf *sb, struct socket *so)
+{
+
+	sbflush_internal(sb);
+	(void)chgsbsize(so->so_cred->cr_uidinfo, &sb->sb_hiwat, 0,
+	    RLIM_INFINITY);
+	sb->sb_mbmax = 0;
+}
+
+void
+sbrelease_locked(struct sockbuf *sb, struct socket *so)
+{
+
+	SOCKBUF_LOCK_ASSERT(sb);
+
+	sbrelease_internal(sb, so);
+}
+
+void
+sbrelease(struct sockbuf *sb, struct socket *so)
+{
+
+	SOCKBUF_LOCK(sb);
+	sbrelease_locked(sb, so);
+	SOCKBUF_UNLOCK(sb);
+}
+
+void
+sbdestroy(struct sockbuf *sb, struct socket *so)
+{
+
+	sbrelease_internal(sb, so);
+}
+
+/*
+ * Routines to add and remove data from an mbuf queue.
+ *
+ * The routines sbappend() or sbappendrecord() are normally called to append
+ * new mbufs to a socket buffer, after checking that adequate space is
+ * available, comparing the function sbspace() with the amount of data to be
+ * added.  sbappendrecord() differs from sbappend() in that data supplied is
+ * treated as the beginning of a new record.  To place a sender's address,
+ * optional access rights, and data in a socket receive buffer,
+ * sbappendaddr() should be used.  To place access rights and data in a
+ * socket receive buffer, sbappendrights() should be used.  In either case,
+ * the new data begins a new record.  Note that unlike sbappend() and
+ * sbappendrecord(), these routines check for the caller that there will be
+ * enough space to store the data.  Each fails if there is not enough space,
+ * or if it cannot find mbufs to store additional information in.
+ *
+ * Reliable protocols may use the socket send buffer to hold data awaiting
+ * acknowledgement.  Data is normally copied from a socket send buffer in a
+ * protocol with m_copy for output to a peer, and then removing the data from
+ * the socket buffer with sbdrop() or sbdroprecord() when the data is
+ * acknowledged by the peer.
+ */
+#ifdef SOCKBUF_DEBUG
+void
+sblastrecordchk(struct sockbuf *sb, const char *file, int line)
+{
+	struct mbuf *m = sb->sb_mb;
+
+	SOCKBUF_LOCK_ASSERT(sb);
+
+	while (m && m->m_nextpkt)
+		m = m->m_nextpkt;
+
+	if (m != sb->sb_lastrecord) {
+		printf("%s: sb_mb %p sb_lastrecord %p last %p\n",
+			__func__, sb->sb_mb, sb->sb_lastrecord, m);
+		printf("packet chain:\n");
+		for (m = sb->sb_mb; m != NULL; m = m->m_nextpkt)
+			printf("\t%p\n", m);
+		panic("%s from %s:%u", __func__, file, line);
+	}
+}
+
+void
+sblastmbufchk(struct sockbuf *sb, const char *file, int line)
+{
+	struct mbuf *m = sb->sb_mb;
+	struct mbuf *n;
+
+	SOCKBUF_LOCK_ASSERT(sb);
+
+	while (m && m->m_nextpkt)
+		m = m->m_nextpkt;
+
+	while (m && m->m_next)
+		m = m->m_next;
+
+	if (m != sb->sb_mbtail) {
+		printf("%s: sb_mb %p sb_mbtail %p last %p\n",
+			__func__, sb->sb_mb, sb->sb_mbtail, m);
+		printf("packet tree:\n");
+		for (m = sb->sb_mb; m != NULL; m = m->m_nextpkt) {
+			printf("\t");
+			for (n = m; n != NULL; n = n->m_next)
+				printf("%p ", n);
+			printf("\n");
+		}
+		panic("%s from %s:%u", __func__, file, line);
+	}
+}
+#endif /* SOCKBUF_DEBUG */
+
+#define SBLINKRECORD(sb, m0) do {					\
+	SOCKBUF_LOCK_ASSERT(sb);					\
+	if ((sb)->sb_lastrecord != NULL)				\
+		(sb)->sb_lastrecord->m_nextpkt = (m0);			\
+	else								\
+		(sb)->sb_mb = (m0);					\
+	(sb)->sb_lastrecord = (m0);					\
+} while (/*CONSTCOND*/0)
+
+/*
+ * Append mbuf chain m to the last record in the socket buffer sb.  The
+ * additional space associated the mbuf chain is recorded in sb.  Empty mbufs
+ * are discarded and mbufs are compacted where possible.
+ */
+void
+sbappend_locked(struct sockbuf *sb, struct mbuf *m)
+{
+	struct mbuf *n;
+
+	SOCKBUF_LOCK_ASSERT(sb);
+
+	if (m == 0)
+		return;
+
+	SBLASTRECORDCHK(sb);
+	n = sb->sb_mb;
+	if (n) {
+		while (n->m_nextpkt)
+			n = n->m_nextpkt;
+		do {
+			if (n->m_flags & M_EOR) {
+				sbappendrecord_locked(sb, m); /* XXXXXX!!!! */
+				return;
+			}
+		} while (n->m_next && (n = n->m_next));
+	} else {
+		/*
+		 * XXX Would like to simply use sb_mbtail here, but
+		 * XXX I need to verify that I won't miss an EOR that
+		 * XXX way.
+		 */
+		if ((n = sb->sb_lastrecord) != NULL) {
+			do {
+				if (n->m_flags & M_EOR) {
+					sbappendrecord_locked(sb, m); /* XXXXXX!!!! */
+					return;
+				}
+			} while (n->m_next && (n = n->m_next));
+		} else {
+			/*
+			 * If this is the first record in the socket buffer,
+			 * it's also the last record.
+			 */
+			sb->sb_lastrecord = m;
+		}
+	}
+	sbcompress(sb, m, n);
+	SBLASTRECORDCHK(sb);
+}
+
+/*
+ * Append mbuf chain m to the last record in the socket buffer sb.  The
+ * additional space associated the mbuf chain is recorded in sb.  Empty mbufs
+ * are discarded and mbufs are compacted where possible.
+ */
+void
+sbappend(struct sockbuf *sb, struct mbuf *m)
+{
+
+	SOCKBUF_LOCK(sb);
+	sbappend_locked(sb, m);
+	SOCKBUF_UNLOCK(sb);
+}
+
+/*
+ * This version of sbappend() should only be used when the caller absolutely
+ * knows that there will never be more than one record in the socket buffer,
+ * that is, a stream protocol (such as TCP).
+ */
+void
+sbappendstream_locked(struct sockbuf *sb, struct mbuf *m)
+{
+	SOCKBUF_LOCK_ASSERT(sb);
+
+	KASSERT(m->m_nextpkt == NULL,("sbappendstream 0"));
+	KASSERT(sb->sb_mb == sb->sb_lastrecord,("sbappendstream 1"));
+
+	SBLASTMBUFCHK(sb);
+
+	/* Remove all packet headers and mbuf tags to get a pure data chain. */
+	m_demote(m, 1);
+	
+	sbcompress(sb, m, sb->sb_mbtail);
+
+	sb->sb_lastrecord = sb->sb_mb;
+	SBLASTRECORDCHK(sb);
+}
+
+/*
+ * This version of sbappend() should only be used when the caller absolutely
+ * knows that there will never be more than one record in the socket buffer,
+ * that is, a stream protocol (such as TCP).
+ */
+void
+sbappendstream(struct sockbuf *sb, struct mbuf *m)
+{
+
+	SOCKBUF_LOCK(sb);
+	sbappendstream_locked(sb, m);
+	SOCKBUF_UNLOCK(sb);
+}
+
+#ifdef SOCKBUF_DEBUG
+void
+sbcheck(struct sockbuf *sb)
+{
+	struct mbuf *m;
+	struct mbuf *n = 0;
+	u_long len = 0, mbcnt = 0;
+
+	SOCKBUF_LOCK_ASSERT(sb);
+
+	for (m = sb->sb_mb; m; m = n) {
+	    n = m->m_nextpkt;
+	    for (; m; m = m->m_next) {
+		len += m->m_len;
+		mbcnt += MSIZE;
+		if (m->m_flags & M_EXT) /*XXX*/ /* pretty sure this is bogus */
+			mbcnt += m->m_ext.ext_size;
+	    }
+	}
+	if (len != sb->sb_cc || mbcnt != sb->sb_mbcnt) {
+		printf("cc %ld != %u || mbcnt %ld != %u\n", len, sb->sb_cc,
+		    mbcnt, sb->sb_mbcnt);
+		panic("sbcheck");
+	}
+}
+#endif
+
+/*
+ * As above, except the mbuf chain begins a new record.
+ */
+void
+sbappendrecord_locked(struct sockbuf *sb, struct mbuf *m0)
+{
+	struct mbuf *m;
+
+	SOCKBUF_LOCK_ASSERT(sb);
+
+	if (m0 == 0)
+		return;
+	/*
+	 * Put the first mbuf on the queue.  Note this permits zero length
+	 * records.
+	 */
+	sballoc(sb, m0);
+	SBLASTRECORDCHK(sb);
+	SBLINKRECORD(sb, m0);
+	sb->sb_mbtail = m0;
+	m = m0->m_next;
+	m0->m_next = 0;
+	if (m && (m0->m_flags & M_EOR)) {
+		m0->m_flags &= ~M_EOR;
+		m->m_flags |= M_EOR;
+	}
+	/* always call sbcompress() so it can do SBLASTMBUFCHK() */
+	sbcompress(sb, m, m0);
+}
+
+/*
+ * As above, except the mbuf chain begins a new record.
+ */
+void
+sbappendrecord(struct sockbuf *sb, struct mbuf *m0)
+{
+
+	SOCKBUF_LOCK(sb);
+	sbappendrecord_locked(sb, m0);
+	SOCKBUF_UNLOCK(sb);
+}
+
+/*
+ * Append address and data, and optionally, control (ancillary) data to the
+ * receive queue of a socket.  If present, m0 must include a packet header
+ * with total length.  Returns 0 if no space in sockbuf or insufficient
+ * mbufs.
+ */
+int
+sbappendaddr_locked(struct sockbuf *sb, const struct sockaddr *asa,
+    struct mbuf *m0, struct mbuf *control)
+{
+	struct mbuf *m, *n, *nlast;
+	int space = asa->sa_len;
+
+	SOCKBUF_LOCK_ASSERT(sb);
+
+	if (m0 && (m0->m_flags & M_PKTHDR) == 0)
+		panic("sbappendaddr_locked");
+	if (m0)
+		space += m0->m_pkthdr.len;
+	space += m_length(control, &n);
+
+	if (space > sbspace(sb))
+		return (0);
+#if MSIZE <= 256
+	if (asa->sa_len > MLEN)
+		return (0);
+#endif
+	MGET(m, M_DONTWAIT, MT_SONAME);
+	if (m == 0)
+		return (0);
+	m->m_len = asa->sa_len;
+	bcopy(asa, mtod(m, caddr_t), asa->sa_len);
+	if (n)
+		n->m_next = m0;		/* concatenate data to control */
+	else
+		control = m0;
+	m->m_next = control;
+	for (n = m; n->m_next != NULL; n = n->m_next)
+		sballoc(sb, n);
+	sballoc(sb, n);
+	nlast = n;
+	SBLINKRECORD(sb, m);
+
+	sb->sb_mbtail = nlast;
+	SBLASTMBUFCHK(sb);
+
+	SBLASTRECORDCHK(sb);
+	return (1);
+}
+
+/*
+ * Append address and data, and optionally, control (ancillary) data to the
+ * receive queue of a socket.  If present, m0 must include a packet header
+ * with total length.  Returns 0 if no space in sockbuf or insufficient
+ * mbufs.
+ */
+int
+sbappendaddr(struct sockbuf *sb, const struct sockaddr *asa,
+    struct mbuf *m0, struct mbuf *control)
+{
+	int retval;
+
+	SOCKBUF_LOCK(sb);
+	retval = sbappendaddr_locked(sb, asa, m0, control);
+	SOCKBUF_UNLOCK(sb);
+	return (retval);
+}
+
+int
+sbappendcontrol_locked(struct sockbuf *sb, struct mbuf *m0,
+    struct mbuf *control)
+{
+	struct mbuf *m, *n, *mlast;
+	int space;
+
+	SOCKBUF_LOCK_ASSERT(sb);
+
+	if (control == 0)
+		panic("sbappendcontrol_locked");
+	space = m_length(control, &n) + m_length(m0, NULL);
+
+	if (space > sbspace(sb))
+		return (0);
+	n->m_next = m0;			/* concatenate data to control */
+
+	SBLASTRECORDCHK(sb);
+
+	for (m = control; m->m_next; m = m->m_next)
+		sballoc(sb, m);
+	sballoc(sb, m);
+	mlast = m;
+	SBLINKRECORD(sb, control);
+
+	sb->sb_mbtail = mlast;
+	SBLASTMBUFCHK(sb);
+
+	SBLASTRECORDCHK(sb);
+	return (1);
+}
+
+int
+sbappendcontrol(struct sockbuf *sb, struct mbuf *m0, struct mbuf *control)
+{
+	int retval;
+
+	SOCKBUF_LOCK(sb);
+	retval = sbappendcontrol_locked(sb, m0, control);
+	SOCKBUF_UNLOCK(sb);
+	return (retval);
+}
+
+/*
+ * Append the data in mbuf chain (m) into the socket buffer sb following mbuf
+ * (n).  If (n) is NULL, the buffer is presumed empty.
+ *
+ * When the data is compressed, mbufs in the chain may be handled in one of
+ * three ways:
+ *
+ * (1) The mbuf may simply be dropped, if it contributes nothing (no data, no
+ *     record boundary, and no change in data type).
+ *
+ * (2) The mbuf may be coalesced -- i.e., data in the mbuf may be copied into
+ *     an mbuf already in the socket buffer.  This can occur if an
+ *     appropriate mbuf exists, there is room, and no merging of data types
+ *     will occur.
+ *
+ * (3) The mbuf may be appended to the end of the existing mbuf chain.
+ *
+ * If any of the new mbufs is marked as M_EOR, mark the last mbuf appended as
+ * end-of-record.
+ */
+void
+sbcompress(struct sockbuf *sb, struct mbuf *m, struct mbuf *n)
+{
+	int eor = 0;
+	struct mbuf *o;
+
+	SOCKBUF_LOCK_ASSERT(sb);
+
+	while (m) {
+		eor |= m->m_flags & M_EOR;
+		if (m->m_len == 0 &&
+		    (eor == 0 ||
+		     (((o = m->m_next) || (o = n)) &&
+		      o->m_type == m->m_type))) {
+			if (sb->sb_lastrecord == m)
+				sb->sb_lastrecord = m->m_next;
+			m = m_free(m);
+			continue;
+		}
+		if (n && (n->m_flags & M_EOR) == 0 &&
+		    M_WRITABLE(n) &&
+		    ((sb->sb_flags & SB_NOCOALESCE) == 0) &&
+		    m->m_len <= MCLBYTES / 4 && /* XXX: Don't copy too much */
+		    m->m_len <= M_TRAILINGSPACE(n) &&
+		    n->m_type == m->m_type) {
+			bcopy(mtod(m, caddr_t), mtod(n, caddr_t) + n->m_len,
+			    (unsigned)m->m_len);
+			n->m_len += m->m_len;
+			sb->sb_cc += m->m_len;
+			if (m->m_type != MT_DATA && m->m_type != MT_OOBDATA)
+				/* XXX: Probably don't need.*/
+				sb->sb_ctl += m->m_len;
+			m = m_free(m);
+			continue;
+		}
+		if (n)
+			n->m_next = m;
+		else
+			sb->sb_mb = m;
+		sb->sb_mbtail = m;
+		sballoc(sb, m);
+		n = m;
+		m->m_flags &= ~M_EOR;
+		m = m->m_next;
+		n->m_next = 0;
+	}
+	if (eor) {
+		KASSERT(n != NULL, ("sbcompress: eor && n == NULL"));
+		n->m_flags |= eor;
+	}
+	SBLASTMBUFCHK(sb);
+}
+
+/*
+ * Free all mbufs in a sockbuf.  Check that all resources are reclaimed.
+ */
+static void
+sbflush_internal(struct sockbuf *sb)
+{
+
+	while (sb->sb_mbcnt) {
+		/*
+		 * Don't call sbdrop(sb, 0) if the leading mbuf is non-empty:
+		 * we would loop forever. Panic instead.
+		 */
+		if (!sb->sb_cc && (sb->sb_mb == NULL || sb->sb_mb->m_len))
+			break;
+		sbdrop_internal(sb, (int)sb->sb_cc);
+	}
+	if (sb->sb_cc || sb->sb_mb || sb->sb_mbcnt)
+		panic("sbflush_internal: cc %u || mb %p || mbcnt %u",
+		    sb->sb_cc, (void *)sb->sb_mb, sb->sb_mbcnt);
+}
+
+void
+sbflush_locked(struct sockbuf *sb)
+{
+
+	SOCKBUF_LOCK_ASSERT(sb);
+	sbflush_internal(sb);
+}
+
+void
+sbflush(struct sockbuf *sb)
+{
+
+	SOCKBUF_LOCK(sb);
+	sbflush_locked(sb);
+	SOCKBUF_UNLOCK(sb);
+}
+
+/*
+ * Drop data from (the front of) a sockbuf.
+ */
+static void
+sbdrop_internal(struct sockbuf *sb, int len)
+{
+	struct mbuf *m;
+	struct mbuf *next;
+
+	next = (m = sb->sb_mb) ? m->m_nextpkt : 0;
+	while (len > 0) {
+		if (m == 0) {
+			if (next == 0)
+				panic("sbdrop");
+			m = next;
+			next = m->m_nextpkt;
+			continue;
+		}
+		if (m->m_len > len) {
+			m->m_len -= len;
+			m->m_data += len;
+			sb->sb_cc -= len;
+			if (sb->sb_sndptroff != 0)
+				sb->sb_sndptroff -= len;
+			if (m->m_type != MT_DATA && m->m_type != MT_OOBDATA)
+				sb->sb_ctl -= len;
+			break;
+		}
+		len -= m->m_len;
+		sbfree(sb, m);
+		m = m_free(m);
+	}
+	while (m && m->m_len == 0) {
+		sbfree(sb, m);
+		m = m_free(m);
+	}
+	if (m) {
+		sb->sb_mb = m;
+		m->m_nextpkt = next;
+	} else
+		sb->sb_mb = next;
+	/*
+	 * First part is an inline SB_EMPTY_FIXUP().  Second part makes sure
+	 * sb_lastrecord is up-to-date if we dropped part of the last record.
+	 */
+	m = sb->sb_mb;
+	if (m == NULL) {
+		sb->sb_mbtail = NULL;
+		sb->sb_lastrecord = NULL;
+	} else if (m->m_nextpkt == NULL) {
+		sb->sb_lastrecord = m;
+	}
+}
+
+/*
+ * Drop data from (the front of) a sockbuf.
+ */
+void
+sbdrop_locked(struct sockbuf *sb, int len)
+{
+
+	SOCKBUF_LOCK_ASSERT(sb);
+
+	sbdrop_internal(sb, len);
+}
+
+void
+sbdrop(struct sockbuf *sb, int len)
+{
+
+	SOCKBUF_LOCK(sb);
+	sbdrop_locked(sb, len);
+	SOCKBUF_UNLOCK(sb);
+}
+
+/*
+ * Maintain a pointer and offset pair into the socket buffer mbuf chain to
+ * avoid traversal of the entire socket buffer for larger offsets.
+ */
+struct mbuf *
+sbsndptr(struct sockbuf *sb, u_int off, u_int len, u_int *moff)
+{
+	struct mbuf *m, *ret;
+
+	KASSERT(sb->sb_mb != NULL, ("%s: sb_mb is NULL", __func__));
+	KASSERT(off + len <= sb->sb_cc, ("%s: beyond sb", __func__));
+	KASSERT(sb->sb_sndptroff <= sb->sb_cc, ("%s: sndptroff broken", __func__));
+
+	/*
+	 * Is off below stored offset? Happens on retransmits.
+	 * Just return, we can't help here.
+	 */
+	if (sb->sb_sndptroff > off) {
+		*moff = off;
+		return (sb->sb_mb);
+	}
+
+	/* Return closest mbuf in chain for current offset. */
+	*moff = off - sb->sb_sndptroff;
+	m = ret = sb->sb_sndptr ? sb->sb_sndptr : sb->sb_mb;
+
+	/* Advance by len to be as close as possible for the next transmit. */
+	for (off = off - sb->sb_sndptroff + len - 1;
+	     off > 0 && m != NULL && off >= m->m_len;
+	     m = m->m_next) {
+		sb->sb_sndptroff += m->m_len;
+		off -= m->m_len;
+	}
+	if (off > 0 && m == NULL)
+		panic("%s: sockbuf %p and mbuf %p clashing", __func__, sb, ret);
+	sb->sb_sndptr = m;
+
+	return (ret);
+}
+
+/*
+ * Drop a record off the front of a sockbuf and move the next record to the
+ * front.
+ */
+void
+sbdroprecord_locked(struct sockbuf *sb)
+{
+	struct mbuf *m;
+
+	SOCKBUF_LOCK_ASSERT(sb);
+
+	m = sb->sb_mb;
+	if (m) {
+		sb->sb_mb = m->m_nextpkt;
+		do {
+			sbfree(sb, m);
+			m = m_free(m);
+		} while (m);
+	}
+	SB_EMPTY_FIXUP(sb);
+}
+
+/*
+ * Drop a record off the front of a sockbuf and move the next record to the
+ * front.
+ */
+void
+sbdroprecord(struct sockbuf *sb)
+{
+
+	SOCKBUF_LOCK(sb);
+	sbdroprecord_locked(sb);
+	SOCKBUF_UNLOCK(sb);
+}
+
+/*
+ * Create a "control" mbuf containing the specified data with the specified
+ * type for presentation on a socket buffer.
+ */
+struct mbuf *
+sbcreatecontrol(caddr_t p, int size, int type, int level)
+{
+	struct cmsghdr *cp;
+	struct mbuf *m;
+
+	if (CMSG_SPACE((u_int)size) > MCLBYTES)
+		return ((struct mbuf *) NULL);
+	if (CMSG_SPACE((u_int)size) > MLEN)
+		m = m_getcl(M_DONTWAIT, MT_CONTROL, 0);
+	else
+		m = m_get(M_DONTWAIT, MT_CONTROL);
+	if (m == NULL)
+		return ((struct mbuf *) NULL);
+	cp = mtod(m, struct cmsghdr *);
+	m->m_len = 0;
+	KASSERT(CMSG_SPACE((u_int)size) <= M_TRAILINGSPACE(m),
+	    ("sbcreatecontrol: short mbuf"));
+	if (p != NULL)
+		(void)memcpy(CMSG_DATA(cp), p, size);
+	m->m_len = CMSG_SPACE(size);
+	cp->cmsg_len = CMSG_LEN(size);
+	cp->cmsg_level = level;
+	cp->cmsg_type = type;
+	return (m);
+}
+
+/*
+ * This does the same for socket buffers that sotoxsocket does for sockets:
+ * generate an user-format data structure describing the socket buffer.  Note
+ * that the xsockbuf structure, since it is always embedded in a socket, does
+ * not include a self pointer nor a length.  We make this entry point public
+ * in case some other mechanism needs it.
+ */
+void
+sbtoxsockbuf(struct sockbuf *sb, struct xsockbuf *xsb)
+{
+
+	xsb->sb_cc = sb->sb_cc;
+	xsb->sb_hiwat = sb->sb_hiwat;
+	xsb->sb_mbcnt = sb->sb_mbcnt;
+	xsb->sb_mcnt = sb->sb_mcnt;	
+	xsb->sb_ccnt = sb->sb_ccnt;
+	xsb->sb_mbmax = sb->sb_mbmax;
+	xsb->sb_lowat = sb->sb_lowat;
+	xsb->sb_flags = sb->sb_flags;
+	xsb->sb_timeo = sb->sb_timeo;
+}
+
+/* This takes the place of kern.maxsockbuf, which moved to kern.ipc. */
+static int dummy;
+SYSCTL_INT(_kern, KERN_DUMMY, dummy, CTLFLAG_RW, &dummy, 0, "");
+SYSCTL_OID(_kern_ipc, KIPC_MAXSOCKBUF, maxsockbuf, CTLTYPE_ULONG|CTLFLAG_RW,
+    &sb_max, 0, sysctl_handle_sb_max, "LU", "Maximum socket buffer size");
+SYSCTL_ULONG(_kern_ipc, KIPC_SOCKBUF_WASTE, sockbuf_waste_factor, CTLFLAG_RW,
+    &sb_efficiency, 0, "");