Annotation of sys/kern/uipc_socket2.c, Revision 1.1
1.1 ! nbrk 1: /* $OpenBSD: uipc_socket2.c,v 1.42 2007/02/26 23:53:33 kurt Exp $ */
! 2: /* $NetBSD: uipc_socket2.c,v 1.11 1996/02/04 02:17:55 christos Exp $ */
! 3:
! 4: /*
! 5: * Copyright (c) 1982, 1986, 1988, 1990, 1993
! 6: * The Regents of the University of California. All rights reserved.
! 7: *
! 8: * Redistribution and use in source and binary forms, with or without
! 9: * modification, are permitted provided that the following conditions
! 10: * are met:
! 11: * 1. Redistributions of source code must retain the above copyright
! 12: * notice, this list of conditions and the following disclaimer.
! 13: * 2. Redistributions in binary form must reproduce the above copyright
! 14: * notice, this list of conditions and the following disclaimer in the
! 15: * documentation and/or other materials provided with the distribution.
! 16: * 3. Neither the name of the University nor the names of its contributors
! 17: * may be used to endorse or promote products derived from this software
! 18: * without specific prior written permission.
! 19: *
! 20: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
! 21: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
! 22: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
! 23: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
! 24: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
! 25: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
! 26: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
! 27: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
! 28: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
! 29: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
! 30: * SUCH DAMAGE.
! 31: *
! 32: * @(#)uipc_socket2.c 8.1 (Berkeley) 6/10/93
! 33: */
! 34:
! 35: #include <sys/param.h>
! 36: #include <sys/systm.h>
! 37: #include <sys/proc.h>
! 38: #include <sys/file.h>
! 39: #include <sys/buf.h>
! 40: #include <sys/malloc.h>
! 41: #include <sys/mbuf.h>
! 42: #include <sys/protosw.h>
! 43: #include <sys/socket.h>
! 44: #include <sys/socketvar.h>
! 45: #include <sys/signalvar.h>
! 46: #include <sys/event.h>
! 47:
! 48: /*
! 49: * Primitive routines for operating on sockets and socket buffers
! 50: */
! 51:
! 52: /* strings for sleep message: */
! 53: const char netcon[] = "netcon";
! 54: const char netcls[] = "netcls";
! 55: const char netio[] = "netio";
! 56: const char netlck[] = "netlck";
! 57:
! 58: u_long sb_max = SB_MAX; /* patchable */
! 59:
! 60: /*
! 61: * Procedures to manipulate state flags of socket
! 62: * and do appropriate wakeups. Normal sequence from the
! 63: * active (originating) side is that soisconnecting() is
! 64: * called during processing of connect() call,
! 65: * resulting in an eventual call to soisconnected() if/when the
! 66: * connection is established. When the connection is torn down
! 67: * soisdisconnecting() is called during processing of disconnect() call,
! 68: * and soisdisconnected() is called when the connection to the peer
! 69: * is totally severed. The semantics of these routines are such that
! 70: * connectionless protocols can call soisconnected() and soisdisconnected()
! 71: * only, bypassing the in-progress calls when setting up a ``connection''
! 72: * takes no time.
! 73: *
! 74: * From the passive side, a socket is created with
! 75: * two queues of sockets: so_q0 for connections in progress
! 76: * and so_q for connections already made and awaiting user acceptance.
! 77: * As a protocol is preparing incoming connections, it creates a socket
! 78: * structure queued on so_q0 by calling sonewconn(). When the connection
! 79: * is established, soisconnected() is called, and transfers the
! 80: * socket structure to so_q, making it available to accept().
! 81: *
! 82: * If a socket is closed with sockets on either
! 83: * so_q0 or so_q, these sockets are dropped.
! 84: *
! 85: * If higher level protocols are implemented in
! 86: * the kernel, the wakeups done here will sometimes
! 87: * cause software-interrupt process scheduling.
! 88: */
! 89:
! 90: void
! 91: soisconnecting(struct socket *so)
! 92: {
! 93:
! 94: so->so_state &= ~(SS_ISCONNECTED|SS_ISDISCONNECTING);
! 95: so->so_state |= SS_ISCONNECTING;
! 96: }
! 97:
! 98: void
! 99: soisconnected(struct socket *so)
! 100: {
! 101: struct socket *head = so->so_head;
! 102:
! 103: so->so_state &= ~(SS_ISCONNECTING|SS_ISDISCONNECTING|SS_ISCONFIRMING);
! 104: so->so_state |= SS_ISCONNECTED;
! 105: if (head && soqremque(so, 0)) {
! 106: soqinsque(head, so, 1);
! 107: sorwakeup(head);
! 108: wakeup_one(&head->so_timeo);
! 109: } else {
! 110: wakeup(&so->so_timeo);
! 111: sorwakeup(so);
! 112: sowwakeup(so);
! 113: }
! 114: }
! 115:
! 116: void
! 117: soisdisconnecting(struct socket *so)
! 118: {
! 119:
! 120: so->so_state &= ~SS_ISCONNECTING;
! 121: so->so_state |= (SS_ISDISCONNECTING|SS_CANTRCVMORE|SS_CANTSENDMORE);
! 122: wakeup(&so->so_timeo);
! 123: sowwakeup(so);
! 124: sorwakeup(so);
! 125: }
! 126:
! 127: void
! 128: soisdisconnected(struct socket *so)
! 129: {
! 130:
! 131: so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING);
! 132: so->so_state |= (SS_CANTRCVMORE|SS_CANTSENDMORE|SS_ISDISCONNECTED);
! 133: wakeup(&so->so_timeo);
! 134: sowwakeup(so);
! 135: sorwakeup(so);
! 136: }
! 137:
! 138: /*
! 139: * When an attempt at a new connection is noted on a socket
! 140: * which accepts connections, sonewconn is called. If the
! 141: * connection is possible (subject to space constraints, etc.)
! 142: * then we allocate a new structure, properly linked into the
! 143: * data structure of the original socket, and return this.
! 144: * Connstatus may be 0, or SS_ISCONFIRMING, or SS_ISCONNECTED.
! 145: *
! 146: * Must be called at splsoftnet()
! 147: */
! 148: struct socket *
! 149: sonewconn(struct socket *head, int connstatus)
! 150: {
! 151: struct socket *so;
! 152: int soqueue = connstatus ? 1 : 0;
! 153: extern u_long unpst_sendspace, unpst_recvspace;
! 154: u_long snd_sb_hiwat, rcv_sb_hiwat;
! 155:
! 156: splassert(IPL_SOFTNET);
! 157:
! 158: if (mclpool.pr_nout > mclpool.pr_hardlimit * 95 / 100)
! 159: return ((struct socket *)0);
! 160: if (head->so_qlen + head->so_q0len > head->so_qlimit * 3)
! 161: return ((struct socket *)0);
! 162: so = pool_get(&socket_pool, PR_NOWAIT);
! 163: if (so == NULL)
! 164: return ((struct socket *)0);
! 165: bzero(so, sizeof(*so));
! 166: so->so_type = head->so_type;
! 167: so->so_options = head->so_options &~ SO_ACCEPTCONN;
! 168: so->so_linger = head->so_linger;
! 169: so->so_state = head->so_state | SS_NOFDREF;
! 170: so->so_proto = head->so_proto;
! 171: so->so_timeo = head->so_timeo;
! 172: so->so_pgid = head->so_pgid;
! 173: so->so_euid = head->so_euid;
! 174: so->so_ruid = head->so_ruid;
! 175: so->so_egid = head->so_egid;
! 176: so->so_rgid = head->so_rgid;
! 177: so->so_cpid = head->so_cpid;
! 178: so->so_siguid = head->so_siguid;
! 179: so->so_sigeuid = head->so_sigeuid;
! 180:
! 181: /*
! 182: * If we are tight on mbuf clusters, create the new socket
! 183: * with the minimum. Sorry, you lose.
! 184: */
! 185: snd_sb_hiwat = head->so_snd.sb_hiwat;
! 186: if (sbcheckreserve(snd_sb_hiwat, unpst_sendspace))
! 187: snd_sb_hiwat = unpst_sendspace; /* and udp? */
! 188: rcv_sb_hiwat = head->so_rcv.sb_hiwat;
! 189: if (sbcheckreserve(rcv_sb_hiwat, unpst_recvspace))
! 190: rcv_sb_hiwat = unpst_recvspace; /* and udp? */
! 191:
! 192: (void) soreserve(so, snd_sb_hiwat, rcv_sb_hiwat);
! 193: soqinsque(head, so, soqueue);
! 194: if ((*so->so_proto->pr_usrreq)(so, PRU_ATTACH,
! 195: (struct mbuf *)0, (struct mbuf *)0, (struct mbuf *)0)) {
! 196: (void) soqremque(so, soqueue);
! 197: pool_put(&socket_pool, so);
! 198: return ((struct socket *)0);
! 199: }
! 200: if (connstatus) {
! 201: sorwakeup(head);
! 202: wakeup(&head->so_timeo);
! 203: so->so_state |= connstatus;
! 204: }
! 205: return (so);
! 206: }
! 207:
! 208: void
! 209: soqinsque(struct socket *head, struct socket *so, int q)
! 210: {
! 211:
! 212: #ifdef DIAGNOSTIC
! 213: if (so->so_onq != NULL)
! 214: panic("soqinsque");
! 215: #endif
! 216:
! 217: so->so_head = head;
! 218: if (q == 0) {
! 219: head->so_q0len++;
! 220: so->so_onq = &head->so_q0;
! 221: } else {
! 222: head->so_qlen++;
! 223: so->so_onq = &head->so_q;
! 224: }
! 225: TAILQ_INSERT_TAIL(so->so_onq, so, so_qe);
! 226: }
! 227:
! 228: int
! 229: soqremque(struct socket *so, int q)
! 230: {
! 231: struct socket *head;
! 232:
! 233: head = so->so_head;
! 234: if (q == 0) {
! 235: if (so->so_onq != &head->so_q0)
! 236: return (0);
! 237: head->so_q0len--;
! 238: } else {
! 239: if (so->so_onq != &head->so_q)
! 240: return (0);
! 241: head->so_qlen--;
! 242: }
! 243: TAILQ_REMOVE(so->so_onq, so, so_qe);
! 244: so->so_onq = NULL;
! 245: so->so_head = NULL;
! 246: return (1);
! 247: }
! 248:
! 249: /*
! 250: * Socantsendmore indicates that no more data will be sent on the
! 251: * socket; it would normally be applied to a socket when the user
! 252: * informs the system that no more data is to be sent, by the protocol
! 253: * code (in case PRU_SHUTDOWN). Socantrcvmore indicates that no more data
! 254: * will be received, and will normally be applied to the socket by a
! 255: * protocol when it detects that the peer will send no more data.
! 256: * Data queued for reading in the socket may yet be read.
! 257: */
! 258:
! 259: void
! 260: socantsendmore(struct socket *so)
! 261: {
! 262:
! 263: so->so_state |= SS_CANTSENDMORE;
! 264: sowwakeup(so);
! 265: }
! 266:
! 267: void
! 268: socantrcvmore(struct socket *so)
! 269: {
! 270:
! 271: so->so_state |= SS_CANTRCVMORE;
! 272: sorwakeup(so);
! 273: }
! 274:
! 275: /*
! 276: * Wait for data to arrive at/drain from a socket buffer.
! 277: */
! 278: int
! 279: sbwait(struct sockbuf *sb)
! 280: {
! 281:
! 282: sb->sb_flags |= SB_WAIT;
! 283: return (tsleep(&sb->sb_cc,
! 284: (sb->sb_flags & SB_NOINTR) ? PSOCK : PSOCK | PCATCH, netio,
! 285: sb->sb_timeo));
! 286: }
! 287:
! 288: /*
! 289: * Lock a sockbuf already known to be locked;
! 290: * return any error returned from sleep (EINTR).
! 291: */
! 292: int
! 293: sb_lock(struct sockbuf *sb)
! 294: {
! 295: int error;
! 296:
! 297: while (sb->sb_flags & SB_LOCK) {
! 298: sb->sb_flags |= SB_WANT;
! 299: error = tsleep(&sb->sb_flags,
! 300: (sb->sb_flags & SB_NOINTR) ?
! 301: PSOCK : PSOCK|PCATCH, netlck, 0);
! 302: if (error)
! 303: return (error);
! 304: }
! 305: sb->sb_flags |= SB_LOCK;
! 306: return (0);
! 307: }
! 308:
! 309: /*
! 310: * Wakeup processes waiting on a socket buffer.
! 311: * Do asynchronous notification via SIGIO
! 312: * if the socket has the SS_ASYNC flag set.
! 313: */
! 314: void
! 315: sowakeup(struct socket *so, struct sockbuf *sb)
! 316: {
! 317: selwakeup(&sb->sb_sel);
! 318: sb->sb_flags &= ~SB_SEL;
! 319: if (sb->sb_flags & SB_WAIT) {
! 320: sb->sb_flags &= ~SB_WAIT;
! 321: wakeup(&sb->sb_cc);
! 322: }
! 323: if (so->so_state & SS_ASYNC)
! 324: csignal(so->so_pgid, SIGIO, so->so_siguid, so->so_sigeuid);
! 325: KNOTE(&sb->sb_sel.si_note, 0);
! 326: }
! 327:
! 328: /*
! 329: * Socket buffer (struct sockbuf) utility routines.
! 330: *
! 331: * Each socket contains two socket buffers: one for sending data and
! 332: * one for receiving data. Each buffer contains a queue of mbufs,
! 333: * information about the number of mbufs and amount of data in the
! 334: * queue, and other fields allowing select() statements and notification
! 335: * on data availability to be implemented.
! 336: *
! 337: * Data stored in a socket buffer is maintained as a list of records.
! 338: * Each record is a list of mbufs chained together with the m_next
! 339: * field. Records are chained together with the m_nextpkt field. The upper
! 340: * level routine soreceive() expects the following conventions to be
! 341: * observed when placing information in the receive buffer:
! 342: *
! 343: * 1. If the protocol requires each message be preceded by the sender's
! 344: * name, then a record containing that name must be present before
! 345: * any associated data (mbuf's must be of type MT_SONAME).
! 346: * 2. If the protocol supports the exchange of ``access rights'' (really
! 347: * just additional data associated with the message), and there are
! 348: * ``rights'' to be received, then a record containing this data
! 349: * should be present (mbuf's must be of type MT_CONTROL).
! 350: * 3. If a name or rights record exists, then it must be followed by
! 351: * a data record, perhaps of zero length.
! 352: *
! 353: * Before using a new socket structure it is first necessary to reserve
! 354: * buffer space to the socket, by calling sbreserve(). This should commit
! 355: * some of the available buffer space in the system buffer pool for the
! 356: * socket (currently, it does nothing but enforce limits). The space
! 357: * should be released by calling sbrelease() when the socket is destroyed.
! 358: */
! 359:
! 360: int
! 361: soreserve(struct socket *so, u_long sndcc, u_long rcvcc)
! 362: {
! 363:
! 364: if (sbreserve(&so->so_snd, sndcc) == 0)
! 365: goto bad;
! 366: if (sbreserve(&so->so_rcv, rcvcc) == 0)
! 367: goto bad2;
! 368: if (so->so_rcv.sb_lowat == 0)
! 369: so->so_rcv.sb_lowat = 1;
! 370: if (so->so_snd.sb_lowat == 0)
! 371: so->so_snd.sb_lowat = MCLBYTES;
! 372: if (so->so_snd.sb_lowat > so->so_snd.sb_hiwat)
! 373: so->so_snd.sb_lowat = so->so_snd.sb_hiwat;
! 374: return (0);
! 375: bad2:
! 376: sbrelease(&so->so_snd);
! 377: bad:
! 378: return (ENOBUFS);
! 379: }
! 380:
! 381: /*
! 382: * Allot mbufs to a sockbuf.
! 383: * Attempt to scale mbmax so that mbcnt doesn't become limiting
! 384: * if buffering efficiency is near the normal case.
! 385: */
! 386: int
! 387: sbreserve(struct sockbuf *sb, u_long cc)
! 388: {
! 389:
! 390: if (cc == 0 || cc > sb_max)
! 391: return (0);
! 392: sb->sb_hiwat = cc;
! 393: sb->sb_mbmax = min(cc * 2, sb_max + (sb_max / MCLBYTES) * MSIZE);
! 394: if (sb->sb_lowat > sb->sb_hiwat)
! 395: sb->sb_lowat = sb->sb_hiwat;
! 396: return (1);
! 397: }
! 398:
! 399: /*
! 400: * If over 50% of mbuf clusters in use, do not accept any
! 401: * greater than normal request.
! 402: */
! 403: int
! 404: sbcheckreserve(u_long cnt, u_long defcnt)
! 405: {
! 406: if (cnt > defcnt &&
! 407: mclpool.pr_nout> mclpool.pr_hardlimit / 2)
! 408: return (ENOBUFS);
! 409: return (0);
! 410: }
! 411:
! 412: /*
! 413: * Free mbufs held by a socket, and reserved mbuf space.
! 414: */
! 415: void
! 416: sbrelease(struct sockbuf *sb)
! 417: {
! 418:
! 419: sbflush(sb);
! 420: sb->sb_hiwat = sb->sb_mbmax = 0;
! 421: }
! 422:
! 423: /*
! 424: * Routines to add and remove
! 425: * data from an mbuf queue.
! 426: *
! 427: * The routines sbappend() or sbappendrecord() are normally called to
! 428: * append new mbufs to a socket buffer, after checking that adequate
! 429: * space is available, comparing the function sbspace() with the amount
! 430: * of data to be added. sbappendrecord() differs from sbappend() in
! 431: * that data supplied is treated as the beginning of a new record.
! 432: * To place a sender's address, optional access rights, and data in a
! 433: * socket receive buffer, sbappendaddr() should be used. To place
! 434: * access rights and data in a socket receive buffer, sbappendrights()
! 435: * should be used. In either case, the new data begins a new record.
! 436: * Note that unlike sbappend() and sbappendrecord(), these routines check
! 437: * for the caller that there will be enough space to store the data.
! 438: * Each fails if there is not enough space, or if it cannot find mbufs
! 439: * to store additional information in.
! 440: *
! 441: * Reliable protocols may use the socket send buffer to hold data
! 442: * awaiting acknowledgement. Data is normally copied from a socket
! 443: * send buffer in a protocol with m_copy for output to a peer,
! 444: * and then removing the data from the socket buffer with sbdrop()
! 445: * or sbdroprecord() when the data is acknowledged by the peer.
! 446: */
! 447:
! 448: #ifdef SOCKBUF_DEBUG
! 449: void
! 450: sblastrecordchk(struct sockbuf *sb, const char *where)
! 451: {
! 452: struct mbuf *m = sb->sb_mb;
! 453:
! 454: while (m && m->m_nextpkt)
! 455: m = m->m_nextpkt;
! 456:
! 457: if (m != sb->sb_lastrecord) {
! 458: printf("sblastrecordchk: sb_mb %p sb_lastrecord %p last %p\n",
! 459: sb->sb_mb, sb->sb_lastrecord, m);
! 460: printf("packet chain:\n");
! 461: for (m = sb->sb_mb; m != NULL; m = m->m_nextpkt)
! 462: printf("\t%p\n", m);
! 463: panic("sblastrecordchk from %s", where);
! 464: }
! 465: }
! 466:
! 467: void
! 468: sblastmbufchk(struct sockbuf *sb, const char *where)
! 469: {
! 470: struct mbuf *m = sb->sb_mb;
! 471: struct mbuf *n;
! 472:
! 473: while (m && m->m_nextpkt)
! 474: m = m->m_nextpkt;
! 475:
! 476: while (m && m->m_next)
! 477: m = m->m_next;
! 478:
! 479: if (m != sb->sb_mbtail) {
! 480: printf("sblastmbufchk: sb_mb %p sb_mbtail %p last %p\n",
! 481: sb->sb_mb, sb->sb_mbtail, m);
! 482: printf("packet tree:\n");
! 483: for (m = sb->sb_mb; m != NULL; m = m->m_nextpkt) {
! 484: printf("\t");
! 485: for (n = m; n != NULL; n = n->m_next)
! 486: printf("%p ", n);
! 487: printf("\n");
! 488: }
! 489: panic("sblastmbufchk from %s", where);
! 490: }
! 491: }
! 492: #endif /* SOCKBUF_DEBUG */
! 493:
! 494: #define SBLINKRECORD(sb, m0) \
! 495: do { \
! 496: if ((sb)->sb_lastrecord != NULL) \
! 497: (sb)->sb_lastrecord->m_nextpkt = (m0); \
! 498: else \
! 499: (sb)->sb_mb = (m0); \
! 500: (sb)->sb_lastrecord = (m0); \
! 501: } while (/*CONSTCOND*/0)
! 502:
! 503: /*
! 504: * Append mbuf chain m to the last record in the
! 505: * socket buffer sb. The additional space associated
! 506: * the mbuf chain is recorded in sb. Empty mbufs are
! 507: * discarded and mbufs are compacted where possible.
! 508: */
! 509: void
! 510: sbappend(struct sockbuf *sb, struct mbuf *m)
! 511: {
! 512: struct mbuf *n;
! 513:
! 514: if (m == NULL)
! 515: return;
! 516:
! 517: SBLASTRECORDCHK(sb, "sbappend 1");
! 518:
! 519: if ((n = sb->sb_lastrecord) != NULL) {
! 520: /*
! 521: * XXX Would like to simply use sb_mbtail here, but
! 522: * XXX I need to verify that I won't miss an EOR that
! 523: * XXX way.
! 524: */
! 525: do {
! 526: if (n->m_flags & M_EOR) {
! 527: sbappendrecord(sb, m); /* XXXXXX!!!! */
! 528: return;
! 529: }
! 530: } while (n->m_next && (n = n->m_next));
! 531: } else {
! 532: /*
! 533: * If this is the first record in the socket buffer, it's
! 534: * also the last record.
! 535: */
! 536: sb->sb_lastrecord = m;
! 537: }
! 538: sbcompress(sb, m, n);
! 539: SBLASTRECORDCHK(sb, "sbappend 2");
! 540: }
! 541:
! 542: /*
! 543: * This version of sbappend() should only be used when the caller
! 544: * absolutely knows that there will never be more than one record
! 545: * in the socket buffer, that is, a stream protocol (such as TCP).
! 546: */
! 547: void
! 548: sbappendstream(struct sockbuf *sb, struct mbuf *m)
! 549: {
! 550:
! 551: KDASSERT(m->m_nextpkt == NULL);
! 552: KASSERT(sb->sb_mb == sb->sb_lastrecord);
! 553:
! 554: SBLASTMBUFCHK(sb, __func__);
! 555:
! 556: sbcompress(sb, m, sb->sb_mbtail);
! 557:
! 558: sb->sb_lastrecord = sb->sb_mb;
! 559: SBLASTRECORDCHK(sb, __func__);
! 560: }
! 561:
! 562: #ifdef SOCKBUF_DEBUG
! 563: void
! 564: sbcheck(struct sockbuf *sb)
! 565: {
! 566: struct mbuf *m;
! 567: u_long len = 0, mbcnt = 0;
! 568:
! 569: for (m = sb->sb_mb; m; m = m->m_next) {
! 570: len += m->m_len;
! 571: mbcnt += MSIZE;
! 572: if (m->m_flags & M_EXT)
! 573: mbcnt += m->m_ext.ext_size;
! 574: if (m->m_nextpkt)
! 575: panic("sbcheck nextpkt");
! 576: }
! 577: if (len != sb->sb_cc || mbcnt != sb->sb_mbcnt) {
! 578: printf("cc %lu != %lu || mbcnt %lu != %lu\n", len, sb->sb_cc,
! 579: mbcnt, sb->sb_mbcnt);
! 580: panic("sbcheck");
! 581: }
! 582: }
! 583: #endif
! 584:
! 585: /*
! 586: * As above, except the mbuf chain
! 587: * begins a new record.
! 588: */
! 589: void
! 590: sbappendrecord(struct sockbuf *sb, struct mbuf *m0)
! 591: {
! 592: struct mbuf *m;
! 593:
! 594: if (m0 == NULL)
! 595: return;
! 596:
! 597: /*
! 598: * Put the first mbuf on the queue.
! 599: * Note this permits zero length records.
! 600: */
! 601: sballoc(sb, m0);
! 602: SBLASTRECORDCHK(sb, "sbappendrecord 1");
! 603: SBLINKRECORD(sb, m0);
! 604: m = m0->m_next;
! 605: m0->m_next = NULL;
! 606: if (m && (m0->m_flags & M_EOR)) {
! 607: m0->m_flags &= ~M_EOR;
! 608: m->m_flags |= M_EOR;
! 609: }
! 610: sbcompress(sb, m, m0);
! 611: SBLASTRECORDCHK(sb, "sbappendrecord 2");
! 612: }
! 613:
! 614: /*
! 615: * As above except that OOB data
! 616: * is inserted at the beginning of the sockbuf,
! 617: * but after any other OOB data.
! 618: */
! 619: void
! 620: sbinsertoob(struct sockbuf *sb, struct mbuf *m0)
! 621: {
! 622: struct mbuf *m, **mp;
! 623:
! 624: if (m0 == NULL)
! 625: return;
! 626:
! 627: SBLASTRECORDCHK(sb, "sbinsertoob 1");
! 628:
! 629: for (mp = &sb->sb_mb; (m = *mp) != NULL; mp = &((*mp)->m_nextpkt)) {
! 630: again:
! 631: switch (m->m_type) {
! 632:
! 633: case MT_OOBDATA:
! 634: continue; /* WANT next train */
! 635:
! 636: case MT_CONTROL:
! 637: if ((m = m->m_next) != NULL)
! 638: goto again; /* inspect THIS train further */
! 639: }
! 640: break;
! 641: }
! 642: /*
! 643: * Put the first mbuf on the queue.
! 644: * Note this permits zero length records.
! 645: */
! 646: sballoc(sb, m0);
! 647: m0->m_nextpkt = *mp;
! 648: if (*mp == NULL) {
! 649: /* m0 is actually the new tail */
! 650: sb->sb_lastrecord = m0;
! 651: }
! 652: *mp = m0;
! 653: m = m0->m_next;
! 654: m0->m_next = NULL;
! 655: if (m && (m0->m_flags & M_EOR)) {
! 656: m0->m_flags &= ~M_EOR;
! 657: m->m_flags |= M_EOR;
! 658: }
! 659: sbcompress(sb, m, m0);
! 660: SBLASTRECORDCHK(sb, "sbinsertoob 2");
! 661: }
! 662:
! 663: /*
! 664: * Append address and data, and optionally, control (ancillary) data
! 665: * to the receive queue of a socket. If present,
! 666: * m0 must include a packet header with total length.
! 667: * Returns 0 if no space in sockbuf or insufficient mbufs.
! 668: */
! 669: int
! 670: sbappendaddr(struct sockbuf *sb, struct sockaddr *asa, struct mbuf *m0,
! 671: struct mbuf *control)
! 672: {
! 673: struct mbuf *m, *n, *nlast;
! 674: int space = asa->sa_len;
! 675:
! 676: if (m0 && (m0->m_flags & M_PKTHDR) == 0)
! 677: panic("sbappendaddr");
! 678: if (m0)
! 679: space += m0->m_pkthdr.len;
! 680: for (n = control; n; n = n->m_next) {
! 681: space += n->m_len;
! 682: if (n->m_next == NULL) /* keep pointer to last control buf */
! 683: break;
! 684: }
! 685: if (space > sbspace(sb))
! 686: return (0);
! 687: if (asa->sa_len > MLEN)
! 688: return (0);
! 689: MGET(m, M_DONTWAIT, MT_SONAME);
! 690: if (m == NULL)
! 691: return (0);
! 692: m->m_len = asa->sa_len;
! 693: bcopy(asa, mtod(m, caddr_t), asa->sa_len);
! 694: if (n)
! 695: n->m_next = m0; /* concatenate data to control */
! 696: else
! 697: control = m0;
! 698: m->m_next = control;
! 699:
! 700: SBLASTRECORDCHK(sb, "sbappendaddr 1");
! 701:
! 702: for (n = m; n->m_next != NULL; n = n->m_next)
! 703: sballoc(sb, n);
! 704: sballoc(sb, n);
! 705: nlast = n;
! 706: SBLINKRECORD(sb, m);
! 707:
! 708: sb->sb_mbtail = nlast;
! 709: SBLASTMBUFCHK(sb, "sbappendaddr");
! 710:
! 711: SBLASTRECORDCHK(sb, "sbappendaddr 2");
! 712:
! 713: return (1);
! 714: }
! 715:
! 716: int
! 717: sbappendcontrol(struct sockbuf *sb, struct mbuf *m0, struct mbuf *control)
! 718: {
! 719: struct mbuf *m, *mlast, *n;
! 720: int space = 0;
! 721:
! 722: if (control == NULL)
! 723: panic("sbappendcontrol");
! 724: for (m = control; ; m = m->m_next) {
! 725: space += m->m_len;
! 726: if (m->m_next == NULL)
! 727: break;
! 728: }
! 729: n = m; /* save pointer to last control buffer */
! 730: for (m = m0; m; m = m->m_next)
! 731: space += m->m_len;
! 732: if (space > sbspace(sb))
! 733: return (0);
! 734: n->m_next = m0; /* concatenate data to control */
! 735:
! 736: SBLASTRECORDCHK(sb, "sbappendcontrol 1");
! 737:
! 738: for (m = control; m->m_next != NULL; m = m->m_next)
! 739: sballoc(sb, m);
! 740: sballoc(sb, m);
! 741: mlast = m;
! 742: SBLINKRECORD(sb, control);
! 743:
! 744: sb->sb_mbtail = mlast;
! 745: SBLASTMBUFCHK(sb, "sbappendcontrol");
! 746:
! 747: SBLASTRECORDCHK(sb, "sbappendcontrol 2");
! 748:
! 749: return (1);
! 750: }
! 751:
! 752: /*
! 753: * Compress mbuf chain m into the socket
! 754: * buffer sb following mbuf n. If n
! 755: * is null, the buffer is presumed empty.
! 756: */
! 757: void
! 758: sbcompress(struct sockbuf *sb, struct mbuf *m, struct mbuf *n)
! 759: {
! 760: int eor = 0;
! 761: struct mbuf *o;
! 762:
! 763: while (m) {
! 764: eor |= m->m_flags & M_EOR;
! 765: if (m->m_len == 0 &&
! 766: (eor == 0 ||
! 767: (((o = m->m_next) || (o = n)) &&
! 768: o->m_type == m->m_type))) {
! 769: if (sb->sb_lastrecord == m)
! 770: sb->sb_lastrecord = m->m_next;
! 771: m = m_free(m);
! 772: continue;
! 773: }
! 774: if (n && (n->m_flags & M_EOR) == 0 &&
! 775: /* M_TRAILINGSPACE() checks buffer writeability */
! 776: m->m_len <= MCLBYTES / 4 && /* XXX Don't copy too much */
! 777: m->m_len <= M_TRAILINGSPACE(n) &&
! 778: n->m_type == m->m_type) {
! 779: bcopy(mtod(m, caddr_t), mtod(n, caddr_t) + n->m_len,
! 780: (unsigned)m->m_len);
! 781: n->m_len += m->m_len;
! 782: sb->sb_cc += m->m_len;
! 783: if (m->m_type != MT_CONTROL && m->m_type != MT_SONAME)
! 784: sb->sb_datacc += m->m_len;
! 785: m = m_free(m);
! 786: continue;
! 787: }
! 788: if (n)
! 789: n->m_next = m;
! 790: else
! 791: sb->sb_mb = m;
! 792: sb->sb_mbtail = m;
! 793: sballoc(sb, m);
! 794: n = m;
! 795: m->m_flags &= ~M_EOR;
! 796: m = m->m_next;
! 797: n->m_next = NULL;
! 798: }
! 799: if (eor) {
! 800: if (n)
! 801: n->m_flags |= eor;
! 802: else
! 803: printf("semi-panic: sbcompress");
! 804: }
! 805: SBLASTMBUFCHK(sb, __func__);
! 806: }
! 807:
! 808: /*
! 809: * Free all mbufs in a sockbuf.
! 810: * Check that all resources are reclaimed.
! 811: */
! 812: void
! 813: sbflush(struct sockbuf *sb)
! 814: {
! 815:
! 816: KASSERT((sb->sb_flags & SB_LOCK) == 0);
! 817:
! 818: while (sb->sb_mbcnt)
! 819: sbdrop(sb, (int)sb->sb_cc);
! 820:
! 821: KASSERT(sb->sb_cc == 0);
! 822: KASSERT(sb->sb_datacc == 0);
! 823: KASSERT(sb->sb_mb == NULL);
! 824: KASSERT(sb->sb_mbtail == NULL);
! 825: KASSERT(sb->sb_lastrecord == NULL);
! 826: }
! 827:
! 828: /*
! 829: * Drop data from (the front of) a sockbuf.
! 830: */
! 831: void
! 832: sbdrop(struct sockbuf *sb, int len)
! 833: {
! 834: struct mbuf *m, *mn;
! 835: struct mbuf *next;
! 836:
! 837: next = (m = sb->sb_mb) ? m->m_nextpkt : 0;
! 838: while (len > 0) {
! 839: if (m == NULL) {
! 840: if (next == NULL)
! 841: panic("sbdrop");
! 842: m = next;
! 843: next = m->m_nextpkt;
! 844: continue;
! 845: }
! 846: if (m->m_len > len) {
! 847: m->m_len -= len;
! 848: m->m_data += len;
! 849: sb->sb_cc -= len;
! 850: if (m->m_type != MT_CONTROL && m->m_type != MT_SONAME)
! 851: sb->sb_datacc -= len;
! 852: break;
! 853: }
! 854: len -= m->m_len;
! 855: sbfree(sb, m);
! 856: MFREE(m, mn);
! 857: m = mn;
! 858: }
! 859: while (m && m->m_len == 0) {
! 860: sbfree(sb, m);
! 861: MFREE(m, mn);
! 862: m = mn;
! 863: }
! 864: if (m) {
! 865: sb->sb_mb = m;
! 866: m->m_nextpkt = next;
! 867: } else
! 868: sb->sb_mb = next;
! 869: /*
! 870: * First part is an inline SB_EMPTY_FIXUP(). Second part
! 871: * makes sure sb_lastrecord is up-to-date if we dropped
! 872: * part of the last record.
! 873: */
! 874: m = sb->sb_mb;
! 875: if (m == NULL) {
! 876: sb->sb_mbtail = NULL;
! 877: sb->sb_lastrecord = NULL;
! 878: } else if (m->m_nextpkt == NULL)
! 879: sb->sb_lastrecord = m;
! 880: }
! 881:
! 882: /*
! 883: * Drop a record off the front of a sockbuf
! 884: * and move the next record to the front.
! 885: */
! 886: void
! 887: sbdroprecord(struct sockbuf *sb)
! 888: {
! 889: struct mbuf *m, *mn;
! 890:
! 891: m = sb->sb_mb;
! 892: if (m) {
! 893: sb->sb_mb = m->m_nextpkt;
! 894: do {
! 895: sbfree(sb, m);
! 896: MFREE(m, mn);
! 897: } while ((m = mn) != NULL);
! 898: }
! 899: SB_EMPTY_FIXUP(sb);
! 900: }
! 901:
! 902: /*
! 903: * Create a "control" mbuf containing the specified data
! 904: * with the specified type for presentation on a socket buffer.
! 905: */
! 906: struct mbuf *
! 907: sbcreatecontrol(caddr_t p, int size, int type, int level)
! 908: {
! 909: struct cmsghdr *cp;
! 910: struct mbuf *m;
! 911:
! 912: if (CMSG_SPACE(size) > MCLBYTES) {
! 913: printf("sbcreatecontrol: message too large %d\n", size);
! 914: return NULL;
! 915: }
! 916:
! 917: if ((m = m_get(M_DONTWAIT, MT_CONTROL)) == NULL)
! 918: return ((struct mbuf *) NULL);
! 919: if (CMSG_SPACE(size) > MLEN) {
! 920: MCLGET(m, M_DONTWAIT);
! 921: if ((m->m_flags & M_EXT) == 0) {
! 922: m_free(m);
! 923: return NULL;
! 924: }
! 925: }
! 926: cp = mtod(m, struct cmsghdr *);
! 927: bcopy(p, CMSG_DATA(cp), size);
! 928: m->m_len = CMSG_SPACE(size);
! 929: cp->cmsg_len = CMSG_LEN(size);
! 930: cp->cmsg_level = level;
! 931: cp->cmsg_type = type;
! 932: return (m);
! 933: }
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