1 /* 2 * Copyright (c) 2005 Jeffrey M. Hsu. All rights reserved. 3 * Copyright (c) 1982, 1986, 1988, 1990, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. All advertising materials mentioning features or use of this software 15 * must display the following acknowledgement: 16 * This product includes software developed by the University of 17 * California, Berkeley and its contributors. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)uipc_socket2.c 8.1 (Berkeley) 6/10/93 35 * $FreeBSD: src/sys/kern/uipc_socket2.c,v 1.55.2.17 2002/08/31 19:04:55 dwmalone Exp $ 36 * $DragonFly: src/sys/kern/uipc_socket2.c,v 1.33 2008/09/02 16:17:52 dillon Exp $ 37 */ 38 39 #include "opt_param.h" 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/domain.h> 43 #include <sys/file.h> /* for maxfiles */ 44 #include <sys/kernel.h> 45 #include <sys/proc.h> 46 #include <sys/malloc.h> 47 #include <sys/mbuf.h> 48 #include <sys/protosw.h> 49 #include <sys/resourcevar.h> 50 #include <sys/stat.h> 51 #include <sys/socket.h> 52 #include <sys/socketvar.h> 53 #include <sys/socketops.h> 54 #include <sys/signalvar.h> 55 #include <sys/sysctl.h> 56 #include <sys/aio.h> /* for aio_swake proto */ 57 #include <sys/event.h> 58 59 #include <sys/thread2.h> 60 #include <sys/msgport2.h> 61 #include <sys/socketvar2.h> 62 63 int maxsockets; 64 65 /* 66 * Primitive routines for operating on sockets and socket buffers 67 */ 68 69 u_long sb_max = SB_MAX; 70 u_long sb_max_adj = 71 SB_MAX * MCLBYTES / (MSIZE + MCLBYTES); /* adjusted sb_max */ 72 73 static u_long sb_efficiency = 8; /* parameter for sbreserve() */ 74 75 /************************************************************************ 76 * signalsockbuf procedures * 77 ************************************************************************/ 78 79 /* 80 * Wait for data to arrive at/drain from a socket buffer. 81 * 82 * NOTE: Caller must generally hold the ssb_lock (client side lock) since 83 * WAIT/WAKEUP only works for one client at a time. 84 * 85 * NOTE: Caller always retries whatever operation it was waiting on. 86 */ 87 int 88 ssb_wait(struct signalsockbuf *ssb) 89 { 90 uint32_t flags; 91 int pflags; 92 int error; 93 94 pflags = (ssb->ssb_flags & SSB_NOINTR) ? 0 : PCATCH; 95 96 for (;;) { 97 flags = ssb->ssb_flags; 98 cpu_ccfence(); 99 100 /* 101 * WAKEUP and WAIT interlock eachother. We can catch the 102 * race by checking to see if WAKEUP has already been set, 103 * and only setting WAIT if WAKEUP is clear. 104 */ 105 if (flags & SSB_WAKEUP) { 106 if (atomic_cmpset_int(&ssb->ssb_flags, flags, 107 flags & ~SSB_WAKEUP)) { 108 error = 0; 109 break; 110 } 111 continue; 112 } 113 114 /* 115 * Only set WAIT if WAKEUP is clear. 116 */ 117 tsleep_interlock(&ssb->ssb_cc, pflags); 118 if (atomic_cmpset_int(&ssb->ssb_flags, flags, 119 flags | SSB_WAIT)) { 120 error = tsleep(&ssb->ssb_cc, pflags | PINTERLOCKED, 121 "sbwait", ssb->ssb_timeo); 122 break; 123 } 124 } 125 return (error); 126 } 127 128 /* 129 * Lock a sockbuf already known to be locked; 130 * return any error returned from sleep (EINTR). 131 */ 132 int 133 _ssb_lock(struct signalsockbuf *ssb) 134 { 135 uint32_t flags; 136 int pflags; 137 int error; 138 139 pflags = (ssb->ssb_flags & SSB_NOINTR) ? 0 : PCATCH; 140 141 for (;;) { 142 flags = ssb->ssb_flags; 143 cpu_ccfence(); 144 if (flags & SSB_LOCK) { 145 tsleep_interlock(&ssb->ssb_flags, pflags); 146 if (atomic_cmpset_int(&ssb->ssb_flags, flags, 147 flags | SSB_WANT)) { 148 error = tsleep(&ssb->ssb_flags, 149 pflags | PINTERLOCKED, 150 "sblock", 0); 151 if (error) 152 break; 153 } 154 } else { 155 if (atomic_cmpset_int(&ssb->ssb_flags, flags, 156 flags | SSB_LOCK)) { 157 lwkt_gettoken(&ssb->ssb_token); 158 error = 0; 159 break; 160 } 161 } 162 } 163 return (error); 164 } 165 166 /* 167 * This does the same for sockbufs. Note that the xsockbuf structure, 168 * since it is always embedded in a socket, does not include a self 169 * pointer nor a length. We make this entry point public in case 170 * some other mechanism needs it. 171 */ 172 void 173 ssbtoxsockbuf(struct signalsockbuf *ssb, struct xsockbuf *xsb) 174 { 175 xsb->sb_cc = ssb->ssb_cc; 176 xsb->sb_hiwat = ssb->ssb_hiwat; 177 xsb->sb_mbcnt = ssb->ssb_mbcnt; 178 xsb->sb_mbmax = ssb->ssb_mbmax; 179 xsb->sb_lowat = ssb->ssb_lowat; 180 xsb->sb_flags = ssb->ssb_flags; 181 xsb->sb_timeo = ssb->ssb_timeo; 182 } 183 184 185 /************************************************************************ 186 * Procedures which manipulate socket state flags, wakeups, etc. * 187 ************************************************************************ 188 * 189 * Normal sequence from the active (originating) side is that 190 * soisconnecting() is called during processing of connect() call, resulting 191 * in an eventual call to soisconnected() if/when the connection is 192 * established. When the connection is torn down soisdisconnecting() is 193 * called during processing of disconnect() call, and soisdisconnected() is 194 * called when the connection to the peer is totally severed. 195 * 196 * The semantics of these routines are such that connectionless protocols 197 * can call soisconnected() and soisdisconnected() only, bypassing the 198 * in-progress calls when setting up a ``connection'' takes no time. 199 * 200 * From the passive side, a socket is created with two queues of sockets: 201 * so_incomp for connections in progress and so_comp for connections 202 * already made and awaiting user acceptance. As a protocol is preparing 203 * incoming connections, it creates a socket structure queued on so_incomp 204 * by calling sonewconn(). When the connection is established, 205 * soisconnected() is called, and transfers the socket structure to so_comp, 206 * making it available to accept(). 207 * 208 * If a socket is closed with sockets on either so_incomp or so_comp, these 209 * sockets are dropped. 210 * 211 * If higher level protocols are implemented in the kernel, the wakeups 212 * done here will sometimes cause software-interrupt process scheduling. 213 */ 214 215 void 216 soisconnecting(struct socket *so) 217 { 218 soclrstate(so, SS_ISCONNECTED | SS_ISDISCONNECTING); 219 sosetstate(so, SS_ISCONNECTING); 220 } 221 222 void 223 soisconnected(struct socket *so) 224 { 225 struct socket *head = so->so_head; 226 227 soclrstate(so, SS_ISCONNECTING | SS_ISDISCONNECTING | SS_ISCONFIRMING); 228 sosetstate(so, SS_ISCONNECTED); 229 if (head && (so->so_state & SS_INCOMP)) { 230 if ((so->so_options & SO_ACCEPTFILTER) != 0) { 231 so->so_upcall = head->so_accf->so_accept_filter->accf_callback; 232 so->so_upcallarg = head->so_accf->so_accept_filter_arg; 233 atomic_set_int(&so->so_rcv.ssb_flags, SSB_UPCALL); 234 so->so_options &= ~SO_ACCEPTFILTER; 235 so->so_upcall(so, so->so_upcallarg, 0); 236 return; 237 } 238 239 /* 240 * Listen socket are not per-cpu. 241 */ 242 lwkt_gettoken(&head->so_rcv.ssb_token); 243 TAILQ_REMOVE(&head->so_incomp, so, so_list); 244 head->so_incqlen--; 245 TAILQ_INSERT_TAIL(&head->so_comp, so, so_list); 246 head->so_qlen++; 247 sosetstate(so, SS_COMP); 248 soclrstate(so, SS_INCOMP); 249 lwkt_reltoken(&head->so_rcv.ssb_token); 250 251 /* 252 * XXX head may be on a different protocol thread. 253 * sorwakeup()->sowakeup() is hacked atm. 254 */ 255 sorwakeup(head); 256 wakeup_one(&head->so_timeo); 257 } else { 258 wakeup(&so->so_timeo); 259 sorwakeup(so); 260 sowwakeup(so); 261 } 262 } 263 264 void 265 soisdisconnecting(struct socket *so) 266 { 267 soclrstate(so, SS_ISCONNECTING); 268 sosetstate(so, SS_ISDISCONNECTING | SS_CANTRCVMORE | SS_CANTSENDMORE); 269 wakeup((caddr_t)&so->so_timeo); 270 sowwakeup(so); 271 sorwakeup(so); 272 } 273 274 void 275 soisdisconnected(struct socket *so) 276 { 277 soclrstate(so, SS_ISCONNECTING | SS_ISCONNECTED | SS_ISDISCONNECTING); 278 sosetstate(so, SS_CANTRCVMORE | SS_CANTSENDMORE | SS_ISDISCONNECTED); 279 wakeup((caddr_t)&so->so_timeo); 280 sbdrop(&so->so_snd.sb, so->so_snd.ssb_cc); 281 sowwakeup(so); 282 sorwakeup(so); 283 } 284 285 void 286 soisreconnecting(struct socket *so) 287 { 288 soclrstate(so, SS_ISDISCONNECTING | SS_ISDISCONNECTED | 289 SS_CANTRCVMORE | SS_CANTSENDMORE); 290 sosetstate(so, SS_ISCONNECTING); 291 } 292 293 void 294 soisreconnected(struct socket *so) 295 { 296 soclrstate(so, SS_ISDISCONNECTED | SS_CANTRCVMORE | SS_CANTSENDMORE); 297 soisconnected(so); 298 } 299 300 /* 301 * Set or change the message port a socket receives commands on. 302 * 303 * XXX 304 */ 305 void 306 sosetport(struct socket *so, lwkt_port_t port) 307 { 308 so->so_port = port; 309 } 310 311 /* 312 * When an attempt at a new connection is noted on a socket 313 * which accepts connections, sonewconn is called. If the 314 * connection is possible (subject to space constraints, etc.) 315 * then we allocate a new structure, propoerly linked into the 316 * data structure of the original socket, and return this. 317 * Connstatus may be 0, or SO_ISCONFIRMING, or SO_ISCONNECTED. 318 * 319 * The new socket is returned with one ref and so_pcb assigned. 320 * The reference is implied by so_pcb. 321 */ 322 struct socket * 323 sonewconn(struct socket *head, int connstatus) 324 { 325 struct socket *so; 326 struct socket *sp; 327 struct pru_attach_info ai; 328 329 if (head->so_qlen > 3 * head->so_qlimit / 2) 330 return (NULL); 331 so = soalloc(1); 332 if (so == NULL) 333 return (NULL); 334 335 /* 336 * Set the port prior to attaching the inpcb to the current 337 * cpu's protocol thread (which should be the current thread 338 * but might not be in all cases). This serializes any pcb ops 339 * which occur to our cpu allowing us to complete the attachment 340 * without racing anything. 341 */ 342 sosetport(so, cpu_portfn(mycpu->gd_cpuid)); 343 if ((head->so_options & SO_ACCEPTFILTER) != 0) 344 connstatus = 0; 345 so->so_head = head; 346 so->so_type = head->so_type; 347 so->so_options = head->so_options &~ SO_ACCEPTCONN; 348 so->so_linger = head->so_linger; 349 350 /* 351 * NOTE: Clearing NOFDREF implies referencing the so with 352 * soreference(). 353 */ 354 so->so_state = head->so_state | SS_NOFDREF | SS_ASSERTINPROG; 355 so->so_proto = head->so_proto; 356 so->so_cred = crhold(head->so_cred); 357 ai.sb_rlimit = NULL; 358 ai.p_ucred = NULL; 359 ai.fd_rdir = NULL; /* jail code cruft XXX JH */ 360 361 /* 362 * Reserve space and call pru_attach. We can direct-call the 363 * function since we're already in the protocol thread. 364 */ 365 if (soreserve(so, head->so_snd.ssb_hiwat, 366 head->so_rcv.ssb_hiwat, NULL) || 367 so_pru_attach_direct(so, 0, &ai)) { 368 so->so_head = NULL; 369 soclrstate(so, SS_ASSERTINPROG); 370 sofree(so); /* remove implied pcb ref */ 371 return (NULL); 372 } 373 KKASSERT(so->so_refs == 2); /* attach + our base ref */ 374 sofree(so); 375 KKASSERT(so->so_port != NULL); 376 so->so_rcv.ssb_lowat = head->so_rcv.ssb_lowat; 377 so->so_snd.ssb_lowat = head->so_snd.ssb_lowat; 378 so->so_rcv.ssb_timeo = head->so_rcv.ssb_timeo; 379 so->so_snd.ssb_timeo = head->so_snd.ssb_timeo; 380 so->so_rcv.ssb_flags |= head->so_rcv.ssb_flags & 381 (SSB_AUTOSIZE | SSB_AUTOLOWAT); 382 so->so_snd.ssb_flags |= head->so_snd.ssb_flags & 383 (SSB_AUTOSIZE | SSB_AUTOLOWAT); 384 lwkt_gettoken(&head->so_rcv.ssb_token); 385 if (connstatus) { 386 TAILQ_INSERT_TAIL(&head->so_comp, so, so_list); 387 sosetstate(so, SS_COMP); 388 head->so_qlen++; 389 } else { 390 if (head->so_incqlen > head->so_qlimit) { 391 sp = TAILQ_FIRST(&head->so_incomp); 392 TAILQ_REMOVE(&head->so_incomp, sp, so_list); 393 head->so_incqlen--; 394 soclrstate(sp, SS_INCOMP); 395 sp->so_head = NULL; 396 soaborta(sp); 397 } 398 TAILQ_INSERT_TAIL(&head->so_incomp, so, so_list); 399 sosetstate(so, SS_INCOMP); 400 head->so_incqlen++; 401 } 402 lwkt_reltoken(&head->so_rcv.ssb_token); 403 if (connstatus) { 404 /* 405 * XXX head may be on a different protocol thread. 406 * sorwakeup()->sowakeup() is hacked atm. 407 */ 408 sorwakeup(head); 409 wakeup((caddr_t)&head->so_timeo); 410 sosetstate(so, connstatus); 411 } 412 soclrstate(so, SS_ASSERTINPROG); 413 return (so); 414 } 415 416 /* 417 * Socantsendmore indicates that no more data will be sent on the 418 * socket; it would normally be applied to a socket when the user 419 * informs the system that no more data is to be sent, by the protocol 420 * code (in case PRU_SHUTDOWN). Socantrcvmore indicates that no more data 421 * will be received, and will normally be applied to the socket by a 422 * protocol when it detects that the peer will send no more data. 423 * Data queued for reading in the socket may yet be read. 424 */ 425 void 426 socantsendmore(struct socket *so) 427 { 428 sosetstate(so, SS_CANTSENDMORE); 429 sowwakeup(so); 430 } 431 432 void 433 socantrcvmore(struct socket *so) 434 { 435 sosetstate(so, SS_CANTRCVMORE); 436 sorwakeup(so); 437 } 438 439 /* 440 * Wakeup processes waiting on a socket buffer. Do asynchronous notification 441 * via SIGIO if the socket has the SS_ASYNC flag set. 442 * 443 * For users waiting on send/recv try to avoid unnecessary context switch 444 * thrashing. Particularly for senders of large buffers (needs to be 445 * extended to sel and aio? XXX) 446 * 447 * WARNING! Can be called on a foreign socket from the wrong protocol 448 * thread. aka is called on the 'head' listen socket when 449 * a new connection comes in. 450 */ 451 void 452 sowakeup(struct socket *so, struct signalsockbuf *ssb) 453 { 454 struct kqinfo *kqinfo = &ssb->ssb_kq; 455 uint32_t flags; 456 457 /* 458 * Check conditions, set the WAKEUP flag, and clear and signal if 459 * the WAIT flag is found to be set. This interlocks against the 460 * client side. 461 */ 462 for (;;) { 463 flags = ssb->ssb_flags; 464 cpu_ccfence(); 465 466 if ((ssb == &so->so_snd && ssb_space(ssb) >= ssb->ssb_lowat) || 467 (ssb == &so->so_rcv && ssb->ssb_cc >= ssb->ssb_lowat) || 468 (ssb == &so->so_snd && (so->so_state & SS_CANTSENDMORE)) || 469 (ssb == &so->so_rcv && (so->so_state & SS_CANTRCVMORE)) 470 ) { 471 if (atomic_cmpset_int(&ssb->ssb_flags, flags, 472 (flags | SSB_WAKEUP) & ~SSB_WAIT)) { 473 if (flags & SSB_WAIT) 474 wakeup(&ssb->ssb_cc); 475 break; 476 } 477 } else { 478 break; 479 } 480 } 481 482 /* 483 * Misc other events 484 */ 485 if ((so->so_state & SS_ASYNC) && so->so_sigio != NULL) 486 pgsigio(so->so_sigio, SIGIO, 0); 487 if (ssb->ssb_flags & SSB_UPCALL) 488 (*so->so_upcall)(so, so->so_upcallarg, MB_DONTWAIT); 489 if (ssb->ssb_flags & SSB_AIO) 490 aio_swake(so, ssb); 491 KNOTE(&kqinfo->ki_note, 0); 492 493 /* 494 * This is a bit of a hack. Multiple threads can wind up scanning 495 * ki_mlist concurrently due to the fact that this function can be 496 * called on a foreign socket, so we can't afford to block here. 497 */ 498 if (ssb->ssb_flags & SSB_MEVENT) { 499 struct netmsg_so_notify *msg, *nmsg; 500 501 lwkt_gettoken(&kq_token); 502 lwkt_gettoken_hard(&ssb->ssb_token); 503 TAILQ_FOREACH_MUTABLE(msg, &kqinfo->ki_mlist, nm_list, nmsg) { 504 if (msg->nm_predicate(msg)) { 505 TAILQ_REMOVE(&kqinfo->ki_mlist, msg, nm_list); 506 lwkt_replymsg(&msg->base.lmsg, 507 msg->base.lmsg.ms_error); 508 } 509 } 510 if (TAILQ_EMPTY(&ssb->ssb_kq.ki_mlist)) 511 atomic_clear_int(&ssb->ssb_flags, SSB_MEVENT); 512 lwkt_reltoken_hard(&ssb->ssb_token); 513 lwkt_reltoken(&kq_token); 514 } 515 } 516 517 /* 518 * Socket buffer (struct signalsockbuf) utility routines. 519 * 520 * Each socket contains two socket buffers: one for sending data and 521 * one for receiving data. Each buffer contains a queue of mbufs, 522 * information about the number of mbufs and amount of data in the 523 * queue, and other fields allowing kevent()/select()/poll() statements 524 * and notification on data availability to be implemented. 525 * 526 * Data stored in a socket buffer is maintained as a list of records. 527 * Each record is a list of mbufs chained together with the m_next 528 * field. Records are chained together with the m_nextpkt field. The upper 529 * level routine soreceive() expects the following conventions to be 530 * observed when placing information in the receive buffer: 531 * 532 * 1. If the protocol requires each message be preceded by the sender's 533 * name, then a record containing that name must be present before 534 * any associated data (mbuf's must be of type MT_SONAME). 535 * 2. If the protocol supports the exchange of ``access rights'' (really 536 * just additional data associated with the message), and there are 537 * ``rights'' to be received, then a record containing this data 538 * should be present (mbuf's must be of type MT_RIGHTS). 539 * 3. If a name or rights record exists, then it must be followed by 540 * a data record, perhaps of zero length. 541 * 542 * Before using a new socket structure it is first necessary to reserve 543 * buffer space to the socket, by calling sbreserve(). This should commit 544 * some of the available buffer space in the system buffer pool for the 545 * socket (currently, it does nothing but enforce limits). The space 546 * should be released by calling ssb_release() when the socket is destroyed. 547 */ 548 int 549 soreserve(struct socket *so, u_long sndcc, u_long rcvcc, struct rlimit *rl) 550 { 551 if (so->so_snd.ssb_lowat == 0) 552 atomic_set_int(&so->so_snd.ssb_flags, SSB_AUTOLOWAT); 553 if (ssb_reserve(&so->so_snd, sndcc, so, rl) == 0) 554 goto bad; 555 if (ssb_reserve(&so->so_rcv, rcvcc, so, rl) == 0) 556 goto bad2; 557 if (so->so_rcv.ssb_lowat == 0) 558 so->so_rcv.ssb_lowat = 1; 559 if (so->so_snd.ssb_lowat == 0) 560 so->so_snd.ssb_lowat = MCLBYTES; 561 if (so->so_snd.ssb_lowat > so->so_snd.ssb_hiwat) 562 so->so_snd.ssb_lowat = so->so_snd.ssb_hiwat; 563 return (0); 564 bad2: 565 ssb_release(&so->so_snd, so); 566 bad: 567 return (ENOBUFS); 568 } 569 570 static int 571 sysctl_handle_sb_max(SYSCTL_HANDLER_ARGS) 572 { 573 int error = 0; 574 u_long old_sb_max = sb_max; 575 576 error = SYSCTL_OUT(req, arg1, sizeof(int)); 577 if (error || !req->newptr) 578 return (error); 579 error = SYSCTL_IN(req, arg1, sizeof(int)); 580 if (error) 581 return (error); 582 if (sb_max < MSIZE + MCLBYTES) { 583 sb_max = old_sb_max; 584 return (EINVAL); 585 } 586 sb_max_adj = (u_quad_t)sb_max * MCLBYTES / (MSIZE + MCLBYTES); 587 return (0); 588 } 589 590 /* 591 * Allot mbufs to a signalsockbuf. 592 * 593 * Attempt to scale mbmax so that mbcnt doesn't become limiting 594 * if buffering efficiency is near the normal case. 595 * 596 * sb_max only applies to user-sockets (where rl != NULL). It does 597 * not apply to kernel sockets or kernel-controlled sockets. Note 598 * that NFS overrides the sockbuf limits created when nfsd creates 599 * a socket. 600 */ 601 int 602 ssb_reserve(struct signalsockbuf *ssb, u_long cc, struct socket *so, 603 struct rlimit *rl) 604 { 605 /* 606 * rl will only be NULL when we're in an interrupt (eg, in tcp_input) 607 * or when called from netgraph (ie, ngd_attach) 608 */ 609 if (rl && cc > sb_max_adj) 610 cc = sb_max_adj; 611 if (!chgsbsize(so->so_cred->cr_uidinfo, &ssb->ssb_hiwat, cc, 612 rl ? rl->rlim_cur : RLIM_INFINITY)) { 613 return (0); 614 } 615 if (rl) 616 ssb->ssb_mbmax = min(cc * sb_efficiency, sb_max); 617 else 618 ssb->ssb_mbmax = cc * sb_efficiency; 619 620 /* 621 * AUTOLOWAT is set on send buffers and prevents large writes 622 * from generating a huge number of context switches. 623 */ 624 if (ssb->ssb_flags & SSB_AUTOLOWAT) { 625 ssb->ssb_lowat = ssb->ssb_hiwat / 2; 626 if (ssb->ssb_lowat < MCLBYTES) 627 ssb->ssb_lowat = MCLBYTES; 628 } 629 if (ssb->ssb_lowat > ssb->ssb_hiwat) 630 ssb->ssb_lowat = ssb->ssb_hiwat; 631 return (1); 632 } 633 634 /* 635 * Free mbufs held by a socket, and reserved mbuf space. 636 */ 637 void 638 ssb_release(struct signalsockbuf *ssb, struct socket *so) 639 { 640 sbflush(&ssb->sb); 641 (void)chgsbsize(so->so_cred->cr_uidinfo, &ssb->ssb_hiwat, 0, 642 RLIM_INFINITY); 643 ssb->ssb_mbmax = 0; 644 } 645 646 /* 647 * Some routines that return EOPNOTSUPP for entry points that are not 648 * supported by a protocol. Fill in as needed. 649 */ 650 void 651 pr_generic_notsupp(netmsg_t msg) 652 { 653 lwkt_replymsg(&msg->lmsg, EOPNOTSUPP); 654 } 655 656 int 657 pru_sosend_notsupp(struct socket *so, struct sockaddr *addr, struct uio *uio, 658 struct mbuf *top, struct mbuf *control, int flags, 659 struct thread *td) 660 { 661 if (top) 662 m_freem(top); 663 if (control) 664 m_freem(control); 665 return (EOPNOTSUPP); 666 } 667 668 int 669 pru_soreceive_notsupp(struct socket *so, struct sockaddr **paddr, 670 struct uio *uio, struct sockbuf *sio, 671 struct mbuf **controlp, int *flagsp) 672 { 673 return (EOPNOTSUPP); 674 } 675 676 /* 677 * This isn't really a ``null'' operation, but it's the default one 678 * and doesn't do anything destructive. 679 */ 680 void 681 pru_sense_null(netmsg_t msg) 682 { 683 msg->sense.nm_stat->st_blksize = msg->base.nm_so->so_snd.ssb_hiwat; 684 lwkt_replymsg(&msg->lmsg, 0); 685 } 686 687 /* 688 * Make a copy of a sockaddr in a malloced buffer of type M_SONAME. Callers 689 * of this routine assume that it always succeeds, so we have to use a 690 * blockable allocation even though we might be called from a critical thread. 691 */ 692 struct sockaddr * 693 dup_sockaddr(const struct sockaddr *sa) 694 { 695 struct sockaddr *sa2; 696 697 sa2 = kmalloc(sa->sa_len, M_SONAME, M_INTWAIT); 698 bcopy(sa, sa2, sa->sa_len); 699 return (sa2); 700 } 701 702 /* 703 * Create an external-format (``xsocket'') structure using the information 704 * in the kernel-format socket structure pointed to by so. This is done 705 * to reduce the spew of irrelevant information over this interface, 706 * to isolate user code from changes in the kernel structure, and 707 * potentially to provide information-hiding if we decide that 708 * some of this information should be hidden from users. 709 */ 710 void 711 sotoxsocket(struct socket *so, struct xsocket *xso) 712 { 713 xso->xso_len = sizeof *xso; 714 xso->xso_so = so; 715 xso->so_type = so->so_type; 716 xso->so_options = so->so_options; 717 xso->so_linger = so->so_linger; 718 xso->so_state = so->so_state; 719 xso->so_pcb = so->so_pcb; 720 xso->xso_protocol = so->so_proto->pr_protocol; 721 xso->xso_family = so->so_proto->pr_domain->dom_family; 722 xso->so_qlen = so->so_qlen; 723 xso->so_incqlen = so->so_incqlen; 724 xso->so_qlimit = so->so_qlimit; 725 xso->so_timeo = so->so_timeo; 726 xso->so_error = so->so_error; 727 xso->so_pgid = so->so_sigio ? so->so_sigio->sio_pgid : 0; 728 xso->so_oobmark = so->so_oobmark; 729 ssbtoxsockbuf(&so->so_snd, &xso->so_snd); 730 ssbtoxsockbuf(&so->so_rcv, &xso->so_rcv); 731 xso->so_uid = so->so_cred->cr_uid; 732 } 733 734 /* 735 * Here is the definition of some of the basic objects in the kern.ipc 736 * branch of the MIB. 737 */ 738 SYSCTL_NODE(_kern, KERN_IPC, ipc, CTLFLAG_RW, 0, "IPC"); 739 740 /* 741 * This takes the place of kern.maxsockbuf, which moved to kern.ipc. 742 * 743 * NOTE! sb_max only applies to user-created socket buffers. 744 */ 745 static int dummy; 746 SYSCTL_INT(_kern, KERN_DUMMY, dummy, CTLFLAG_RW, &dummy, 0, ""); 747 SYSCTL_OID(_kern_ipc, KIPC_MAXSOCKBUF, maxsockbuf, CTLTYPE_INT|CTLFLAG_RW, 748 &sb_max, 0, sysctl_handle_sb_max, "I", "Maximum socket buffer size"); 749 SYSCTL_INT(_kern_ipc, OID_AUTO, maxsockets, CTLFLAG_RD, 750 &maxsockets, 0, "Maximum number of sockets available"); 751 SYSCTL_INT(_kern_ipc, KIPC_SOCKBUF_WASTE, sockbuf_waste_factor, CTLFLAG_RW, 752 &sb_efficiency, 0, ""); 753 754 /* 755 * Initialize maxsockets 756 */ 757 static void 758 init_maxsockets(void *ignored) 759 { 760 TUNABLE_INT_FETCH("kern.ipc.maxsockets", &maxsockets); 761 maxsockets = imax(maxsockets, imax(maxfiles, nmbclusters)); 762 } 763 SYSINIT(param, SI_BOOT1_TUNABLES, SI_ORDER_ANY, 764 init_maxsockets, NULL); 765 766