/bsd/sys/kern/uipc_sockbuf.cc
C++ | 1119 lines | 730 code | 139 blank | 250 comment | 172 complexity | d1b3238918e354a367b9af8912fc0bca MD5 | raw file
Possible License(s): BSD-3-Clause, 0BSD, MPL-2.0-no-copyleft-exception
- /*-
- * 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 <sys/cdefs.h>
- #include <osv/poll.h>
- #include <osv/clock.hh>
- #include <osv/signal.hh>
- #include <bsd/porting/netport.h>
- #include <bsd/porting/rwlock.h>
- #include <bsd/porting/synch.h>
- #include <bsd/sys/sys/param.h>
- #include <bsd/sys/sys/mbuf.h>
- #include <bsd/sys/sys/protosw.h>
- #include <bsd/sys/sys/socket.h>
- #include <bsd/sys/sys/socketvar.h>
- #include <bsd/sys/sys/libkern.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 =
- (quad_t)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)
- {
- SOCK_LOCK_ASSERT(so);
- so->so_snd.sb_state |= SBS_CANTSENDMORE;
- sowwakeup_locked(so);
- }
- void
- socantsendmore(struct socket *so)
- {
- SOCK_LOCK(so);
- socantsendmore_locked(so);
- SOCK_UNLOCK(so);
- SOCK_UNLOCK_ASSERT(so);
- }
- void
- socantrcvmore_locked(struct socket *so)
- {
- SOCK_LOCK_ASSERT(so);
- so->so_rcv.sb_state |= SBS_CANTRCVMORE;
- sorwakeup_locked(so);
- }
- void
- socantrcvmore(struct socket *so)
- {
- SOCK_LOCK(so);
- socantrcvmore_locked(so);
- SOCK_UNLOCK(so);
- SOCK_UNLOCK_ASSERT(so);
- }
- void sockbuf_iolock::lock(mutex& mtx)
- {
- while (_owner) {
- _wq.wait(mtx);
- }
- _owner = sched::thread::current();
- }
- bool sockbuf_iolock::try_lock(mutex& mtx)
- {
- if (!_owner) {
- _owner = sched::thread::current();
- return true;
- } else {
- return false;
- }
- }
- void sockbuf_iolock::unlock(mutex& mtx)
- {
- _owner = nullptr;
- _wq.wake_all(mtx);
- }
- template<typename Clock>
- int sbwait_tmo(socket* so, struct sockbuf *sb, boost::optional<std::chrono::time_point<Clock>> timeout)
- {
- SOCK_LOCK_ASSERT(so);
- sb->sb_flags |= SB_WAIT;
- sched::timer tmr(*sched::thread::current());
- if (timeout) {
- tmr.set(*timeout);
- }
- signal_catcher sc;
- if (so->so_nc && !so->so_nc_busy) {
- so->so_nc_busy = true;
- sched::thread::wait_for(SOCK_MTX_REF(so), *so->so_nc, sb->sb_cc_wq, tmr, sc);
- so->so_nc_busy = false;
- so->so_nc_wq.wake_all(SOCK_MTX_REF(so));
- } else {
- sched::thread::wait_for(SOCK_MTX_REF(so), so->so_nc_wq, sb->sb_cc_wq, tmr, sc);
- }
- if (sc.interrupted()) {
- return EINTR;
- }
- if (tmr.expired()) {
- return EWOULDBLOCK;
- }
- if (so->so_nc) {
- so->so_nc->process_queue();
- }
- return 0;
- }
- template<typename Clock>
- static inline boost::optional<std::chrono::time_point<Clock>> parse_timeout(int timeout)
- {
- if (timeout == 0) {
- return boost::optional<std::chrono::time_point<Clock>>();
- }
- return boost::optional<std::chrono::time_point<Clock>>(
- Clock::now() + std::chrono::nanoseconds(ticks2ns(timeout)));
- }
- /*
- * Wait for data to arrive at/drain from a socket buffer.
- */
- int
- sbwait(socket* so, struct sockbuf *sb)
- {
- return sbwait_tmo(so, sb, parse_timeout<osv::clock::uptime>(sb->sb_timeo));
- }
- int
- sblock(socket* so, struct sockbuf *sb, int flags)
- {
- SOCK_LOCK_ASSERT(so);
- KASSERT((flags & SBL_VALID) == flags,
- ("sblock: flags invalid (0x%x)", flags));
- if (flags & SBL_WAIT) {
- sb->sb_iolock.lock(SOCK_MTX_REF(so));
- return (0);
- } else {
- if (!sb->sb_iolock.try_lock(SOCK_MTX_REF(so)))
- return (EWOULDBLOCK);
- return (0);
- }
- }
- void
- sbunlock(socket* so, struct sockbuf *sb)
- {
- SOCK_LOCK_ASSERT(so);
- sb->sb_iolock.unlock(SOCK_MTX_REF(so));
- }
- void so_wake_poll(struct socket *so, struct sockbuf *sb)
- {
- /* Read */
- if (&so->so_rcv == sb) {
- if (soreadable(so)) {
- poll_wake(so->fp, (POLLIN | POLLRDNORM));
- sb->sb_flags &= ~SB_SEL;
- }
- }
- /* Write */
- if (&so->so_snd == sb) {
- if (sowriteable(so)) {
- poll_wake(so->fp, (POLLOUT | POLLWRNORM));
- sb->sb_flags &= ~SB_SEL;
- }
- }
- }
- /*
- * 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; 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 = 0;
- SOCK_LOCK_ASSERT(so);
- so_wake_poll(so, sb);
- if (sb->sb_flags & SB_WAIT) {
- sb->sb_flags &= ~SB_WAIT;
- sb->sb_cc_wq.wake_all(SOCK_MTX_REF(so));
- }
- 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 (ret == SU_ISCONNECTED) {
- soisconnected(so);
- }
- }
- /*
- * 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_hdr.mh_next field. Records
- * are chained together with the m_hdr.mh_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.
- *
- * Used during construction, so we can't assert() the mutex is locked -
- * it doesn't exist yet.
- */
- int
- soreserve_internal(struct socket *so, u_long sndcc, u_long rcvcc)
- {
- struct thread *td = NULL;
- if (sbreserve_internal(&so->so_snd, sndcc, so, td) == 0)
- goto bad;
- if (sbreserve_internal(&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 ((u_int)so->so_snd.sb_lowat > so->so_snd.sb_hiwat)
- so->so_snd.sb_lowat = so->so_snd.sb_hiwat;
- return (0);
- bad2:
- sbrelease_internal(&so->so_snd, so);
- bad:
- return (ENOBUFS);
- }
- int
- soreserve(struct socket *so, u_long sndcc, u_long rcvcc)
- {
- SOCK_LOCK(so);
- auto error = soreserve_internal(so, sndcc, rcvcc);
- SOCK_UNLOCK(so);
- return error;
- }
- #if 0
- 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);
- }
- #endif
- /*
- * 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_internal(struct sockbuf *sb, u_long cc, struct socket *so,
- struct thread *td)
- {
- /*
- * 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);
- sb->sb_hiwat = cc;
- sb->sb_mbmax = bsd_min(cc * sb_efficiency, sb_max);
- if ((u_int)sb->sb_lowat > sb->sb_hiwat)
- sb->sb_lowat = sb->sb_hiwat;
- return (1);
- }
- int
- sbreserve_locked(struct sockbuf *sb, u_long cc, struct socket *so,
- struct thread *td)
- {
- SOCK_LOCK_ASSERT(so);
- return sbreserve_internal(sb, cc, so, td);
- }
- int
- sbreserve(struct sockbuf *sb, u_long cc, struct socket *so,
- struct thread *td)
- {
- int error;
- SOCK_LOCK(so);
- error = sbreserve_internal(sb, cc, so, td);
- SOCK_UNLOCK(so);
- return (error);
- }
- /*
- * Free mbufs held by a socket, and reserved mbuf space.
- */
- void
- sbrelease_internal(struct sockbuf *sb, struct socket *so)
- {
- sbflush_internal(sb);
- sb->sb_hiwat = 0;
- sb->sb_mbmax = 0;
- }
- void
- sbrelease_locked(struct sockbuf *sb, struct socket *so)
- {
- SOCK_LOCK_ASSERT(so);
- sbrelease_internal(sb, so);
- }
- void
- sbrelease(struct sockbuf *sb, struct socket *so)
- {
- SOCK_LOCK(so);
- sbrelease_locked(sb, so);
- SOCK_UNLOCK(so);
- }
- 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_hdr.mh_nextpkt)
- m = m->m_hdr.mh_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_hdr.mh_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_hdr.mh_nextpkt)
- m = m->m_hdr.mh_nextpkt;
- while (m && m->m_hdr.mh_next)
- m = m->m_hdr.mh_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_hdr.mh_nextpkt) {
- printf("\t");
- for (n = m; n != NULL; n = n->m_hdr.mh_next)
- printf("%p ", n);
- printf("\n");
- }
- panic("%s from %s:%u", __func__, file, line);
- }
- }
- #endif /* SOCKBUF_DEBUG */
- #define SBLINKRECORD(so, sb, m0) do { \
- SOCK_LOCK_ASSERT(so); \
- if ((sb)->sb_lastrecord != NULL) \
- (sb)->sb_lastrecord->m_hdr.mh_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(socket* so, struct sockbuf *sb, struct mbuf *m)
- {
- struct mbuf *n;
- SOCK_LOCK_ASSERT(so);
- if (m == 0)
- return;
- SBLASTRECORDCHK(sb);
- n = sb->sb_mb;
- if (n) {
- while (n->m_hdr.mh_nextpkt)
- n = n->m_hdr.mh_nextpkt;
- do {
- if (n->m_hdr.mh_flags & M_EOR) {
- sbappendrecord_locked(so, sb, m); /* XXXXXX!!!! */
- return;
- }
- } while (n->m_hdr.mh_next && (n = n->m_hdr.mh_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_hdr.mh_flags & M_EOR) {
- sbappendrecord_locked(so, sb, m); /* XXXXXX!!!! */
- return;
- }
- } while (n->m_hdr.mh_next && (n = n->m_hdr.mh_next));
- } else {
- /*
- * If this is the first record in the socket buffer,
- * it's also the last record.
- */
- sb->sb_lastrecord = m;
- }
- }
- sbcompress(so, 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(socket* so, struct sockbuf *sb, struct mbuf *m)
- {
- SOCK_LOCK(so);
- sbappend_locked(so, sb, m);
- SOCK_UNLOCK(so);
- }
- /*
- * 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(socket* so, struct sockbuf *sb, struct mbuf *m)
- {
- SOCK_LOCK_ASSERT(so);
- KASSERT(m->m_hdr.mh_nextpkt == NULL,("sbappendstream 0"));
- KASSERT(sb->sb_mb == sb->sb_lastrecord,("sbappendstream 1"));
- SBLASTMBUFCHK(sb);
- sbcompress(so, 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(socket* so, struct sockbuf *sb, struct mbuf *m)
- {
- SOCK_LOCK(so);
- sbappendstream_locked(so, sb, m);
- SOCK_UNLOCK(so);
- }
- #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_hdr.mh_nextpkt;
- for (; m; m = m->m_hdr.mh_next) {
- len += m->m_hdr.mh_len;
- mbcnt += MSIZE;
- if (m->m_hdr.mh_flags & M_EXT) /*XXX*/ /* pretty sure this is bogus */
- mbcnt += m->M_dat.MH.MH_dat.MH_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(socket* so, struct sockbuf *sb, struct mbuf *m0)
- {
- struct mbuf *m;
- SOCK_LOCK_ASSERT(so);
- if (m0 == 0)
- return;
- /*
- * Put the first mbuf on the queue. Note this permits zero length
- * records.
- */
- sballoc(sb, m0);
- SBLASTRECORDCHK(sb);
- SBLINKRECORD(so, sb, m0);
- sb->sb_mbtail = m0;
- m = m0->m_hdr.mh_next;
- m0->m_hdr.mh_next = 0;
- if (m && (m0->m_hdr.mh_flags & M_EOR)) {
- m0->m_hdr.mh_flags &= ~M_EOR;
- m->m_hdr.mh_flags |= M_EOR;
- }
- /* always call sbcompress() so it can do SBLASTMBUFCHK() */
- sbcompress(so, sb, m, m0);
- }
- /*
- * As above, except the mbuf chain begins a new record.
- */
- void
- sbappendrecord(socket* so, struct sockbuf *sb, struct mbuf *m0)
- {
- SOCK_LOCK(so);
- sbappendrecord_locked(so, sb, m0);
- SOCK_UNLOCK(so);
- }
- /*
- * 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(socket* so, struct sockbuf *sb, const struct bsd_sockaddr *asa,
- struct mbuf *m0, struct mbuf *control)
- {
- struct mbuf *m, *n, *nlast;
- int space = asa->sa_len;
- SOCK_LOCK_ASSERT(so);
- if (m0 && (m0->m_hdr.mh_flags & M_PKTHDR) == 0)
- panic("sbappendaddr_locked");
- if (m0)
- space += m0->M_dat.MH.MH_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_hdr.mh_len = asa->sa_len;
- bcopy(asa, mtod(m, caddr_t), asa->sa_len);
- if (n)
- n->m_hdr.mh_next = m0; /* concatenate data to control */
- else
- control = m0;
- m->m_hdr.mh_next = control;
- for (n = m; n->m_hdr.mh_next != NULL; n = n->m_hdr.mh_next)
- sballoc(sb, n);
- sballoc(sb, n);
- nlast = n;
- SBLINKRECORD(so, 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(socket* so, struct sockbuf *sb, const struct bsd_sockaddr *asa,
- struct mbuf *m0, struct mbuf *control)
- {
- int retval;
- SOCK_LOCK(so);
- retval = sbappendaddr_locked(so, sb, asa, m0, control);
- SOCK_UNLOCK(so);
- return (retval);
- }
- int
- sbappendcontrol_locked(socket* so, struct sockbuf *sb, struct mbuf *m0,
- struct mbuf *control)
- {
- struct mbuf *m, *n, *mlast;
- int space;
- SOCK_LOCK_ASSERT(so);
- if (control == 0)
- panic("sbappendcontrol_locked");
- space = m_length(control, &n) + m_length(m0, NULL);
- if (space > sbspace(sb))
- return (0);
- n->m_hdr.mh_next = m0; /* concatenate data to control */
- SBLASTRECORDCHK(sb);
- for (m = control; m->m_hdr.mh_next; m = m->m_hdr.mh_next)
- sballoc(sb, m);
- sballoc(sb, m);
- mlast = m;
- SBLINKRECORD(so, sb, control);
- sb->sb_mbtail = mlast;
- SBLASTMBUFCHK(sb);
- SBLASTRECORDCHK(sb);
- return (1);
- }
- int
- sbappendcontrol(socket* so, struct sockbuf *sb, struct mbuf *m0, struct mbuf *control)
- {
- int retval;
- SOCK_LOCK(so);
- retval = sbappendcontrol_locked(so, sb, m0, control);
- SOCK_UNLOCK(so);
- 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(socket* so, struct sockbuf *sb, struct mbuf *m, struct mbuf *n)
- {
- int eor = 0;
- struct mbuf *o;
- SOCK_LOCK_ASSERT(so);
- while (m) {
- eor |= m->m_hdr.mh_flags & M_EOR;
- if (m->m_hdr.mh_len == 0 &&
- (eor == 0 ||
- (((o = m->m_hdr.mh_next) || (o = n)) &&
- o->m_hdr.mh_type == m->m_hdr.mh_type))) {
- if (sb->sb_lastrecord == m)
- sb->sb_lastrecord = m->m_hdr.mh_next;
- m = m_free(m);
- continue;
- }
- if (n && (n->m_hdr.mh_flags & M_EOR) == 0 &&
- M_WRITABLE(n) &&
- ((sb->sb_flags & SB_NOCOALESCE) == 0) &&
- m->m_hdr.mh_len <= MCLBYTES / 4 && /* XXX: Don't copy too much */
- m->m_hdr.mh_len <= M_TRAILINGSPACE(n) &&
- n->m_hdr.mh_type == m->m_hdr.mh_type) {
- bcopy(mtod(m, caddr_t), mtod(n, caddr_t) + n->m_hdr.mh_len,
- (unsigned)m->m_hdr.mh_len);
- n->m_hdr.mh_len += m->m_hdr.mh_len;
- sb->sb_cc += m->m_hdr.mh_len;
- if (m->m_hdr.mh_type != MT_DATA && m->m_hdr.mh_type != MT_OOBDATA)
- /* XXX: Probably don't need.*/
- sb->sb_ctl += m->m_hdr.mh_len;
- m = m_free(m);
- continue;
- }
- if (n)
- n->m_hdr.mh_next = m;
- else
- sb->sb_mb = m;
- sb->sb_mbtail = m;
- sballoc(sb, m);
- n = m;
- m->m_hdr.mh_flags &= ~M_EOR;
- m = m->m_hdr.mh_next;
- n->m_hdr.mh_next = 0;
- }
- if (eor) {
- KASSERT(n != NULL, ("sbcompress: eor && n == NULL"));
- n->m_hdr.mh_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_hdr.mh_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(socket* so, struct sockbuf *sb)
- {
- SOCK_LOCK_ASSERT(so);
- sbflush_internal(sb);
- }
- void
- sbflush(socket* so, struct sockbuf *sb)
- {
- SOCK_LOCK(so);
- sbflush_locked(so, sb);
- SOCK_UNLOCK(so);
- }
- /*
- * 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_hdr.mh_nextpkt : 0;
- while (len > 0) {
- if (m == 0) {
- if (next == 0)
- panic("sbdrop");
- m = next;
- next = m->m_hdr.mh_nextpkt;
- continue;
- }
- if (m->m_hdr.mh_len > len) {
- m->m_hdr.mh_len -= len;
- m->m_hdr.mh_data += len;
- sb->sb_cc -= len;
- if (sb->sb_sndptroff != 0)
- sb->sb_sndptroff -= len;
- if (m->m_hdr.mh_type != MT_DATA && m->m_hdr.mh_type != MT_OOBDATA)
- sb->sb_ctl -= len;
- break;
- }
- len -= m->m_hdr.mh_len;
- sbfree(sb, m);
- m = m_free(m);
- }
- while (m && m->m_hdr.mh_len == 0) {
- sbfree(sb, m);
- m = m_free(m);
- }
- if (m) {
- sb->sb_mb = m;
- m->m_hdr.mh_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_hdr.mh_nextpkt == NULL) {
- sb->sb_lastrecord = m;
- }
- }
- /*
- * Drop data from (the front of) a sockbuf.
- */
- void
- sbdrop_locked(socket* so, struct sockbuf *sb, int len)
- {
- SOCK_LOCK_ASSERT(so);
- sbdrop_internal(sb, len);
- }
- void
- sbdrop(socket* so, struct sockbuf *sb, int len)
- {
- SOCK_LOCK(so);
- sbdrop_locked(so, sb, len);
- SOCK_UNLOCK(so);
- }
- /*
- * 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 >= (u_int)m->m_hdr.mh_len;
- m = m->m_hdr.mh_next) {
- sb->sb_sndptroff += m->m_hdr.mh_len;
- off -= m->m_hdr.mh_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(socket* so, struct sockbuf *sb)
- {
- struct mbuf *m;
- SOCK_LOCK_ASSERT(so);
- m = sb->sb_mb;
- if (m) {
- sb->sb_mb = m->m_hdr.mh_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(socket* so, struct sockbuf *sb)
- {
- SOCK_LOCK(so);
- sbdroprecord_locked(so, sb);
- SOCK_UNLOCK(so);
- }
- /*
- * 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_hdr.mh_len = 0;
- KASSERT(CMSG_SPACE((u_int)size) <= (u_int)M_TRAILINGSPACE(m),
- ("sbcreatecontrol: short mbuf"));
- if (p != NULL)
- (void)memcpy(CMSG_DATA(cp), p, size);
- m->m_hdr.mh_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. */
- 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, "");