1 /* 2 * ng_base.c 3 * 4 * Copyright (c) 1996-1999 Whistle Communications, Inc. 5 * All rights reserved. 6 * 7 * Subject to the following obligations and disclaimer of warranty, use and 8 * redistribution of this software, in source or object code forms, with or 9 * without modifications are expressly permitted by Whistle Communications; 10 * provided, however, that: 11 * 1. Any and all reproductions of the source or object code must include the 12 * copyright notice above and the following disclaimer of warranties; and 13 * 2. No rights are granted, in any manner or form, to use Whistle 14 * Communications, Inc. trademarks, including the mark "WHISTLE 15 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 16 * such appears in the above copyright notice or in the software. 17 * 18 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 19 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 20 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 21 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 22 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 23 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 24 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 25 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 26 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 27 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 28 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 29 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 30 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 31 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 32 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 33 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 34 * OF SUCH DAMAGE. 35 * 36 * Authors: Julian Elischer <julian@freebsd.org> 37 * Archie Cobbs <archie@freebsd.org> 38 * 39 * $FreeBSD$ 40 * $Whistle: ng_base.c,v 1.39 1999/01/28 23:54:53 julian Exp $ 41 */ 42 43 /* 44 * This file implements the base netgraph code. 45 */ 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/errno.h> 50 #include <sys/kdb.h> 51 #include <sys/kernel.h> 52 #include <sys/limits.h> 53 #include <sys/malloc.h> 54 #include <sys/syslog.h> 55 #include <sys/sysctl.h> 56 #include <sys/queue.h> 57 #include <sys/mbuf.h> 58 #include <sys/ctype.h> 59 #include <sys/sysctl.h> 60 61 #include <net/netisr.h> 62 63 #include <netgraph/ng_message.h> 64 #include <netgraph/netgraph.h> 65 #include <netgraph/ng_parse.h> 66 67 MODULE_VERSION(netgraph, NG_ABI_VERSION); 68 69 /* List of all active nodes */ 70 static LIST_HEAD(, ng_node) ng_nodelist; 71 static struct mtx ng_nodelist_mtx; 72 73 /* Mutex that protects the free queue item list */ 74 static struct mtx ngq_mtx; 75 76 #ifdef NETGRAPH_DEBUG 77 78 static SLIST_HEAD(, ng_node) ng_allnodes; 79 static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */ 80 static SLIST_HEAD(, ng_hook) ng_allhooks; 81 static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */ 82 83 static void ng_dumpitems(void); 84 static void ng_dumpnodes(void); 85 static void ng_dumphooks(void); 86 87 #endif /* NETGRAPH_DEBUG */ 88 /* 89 * DEAD versions of the structures. 90 * In order to avoid races, it is sometimes neccesary to point 91 * at SOMETHING even though theoretically, the current entity is 92 * INVALID. Use these to avoid these races. 93 */ 94 struct ng_type ng_deadtype = { 95 NG_ABI_VERSION, 96 "dead", 97 NULL, /* modevent */ 98 NULL, /* constructor */ 99 NULL, /* rcvmsg */ 100 NULL, /* shutdown */ 101 NULL, /* newhook */ 102 NULL, /* findhook */ 103 NULL, /* connect */ 104 NULL, /* rcvdata */ 105 NULL, /* disconnect */ 106 NULL, /* cmdlist */ 107 }; 108 109 struct ng_node ng_deadnode = { 110 "dead", 111 &ng_deadtype, 112 NGF_INVALID, 113 1, /* refs */ 114 0, /* numhooks */ 115 NULL, /* private */ 116 0, /* ID */ 117 LIST_HEAD_INITIALIZER(ng_deadnode.hooks), 118 {}, /* all_nodes list entry */ 119 {}, /* id hashtable list entry */ 120 {}, /* workqueue entry */ 121 { 0, 122 {}, /* should never use! (should hang) */ 123 NULL, 124 &ng_deadnode.nd_input_queue.queue, 125 &ng_deadnode 126 }, 127 #ifdef NETGRAPH_DEBUG 128 ND_MAGIC, 129 __FILE__, 130 __LINE__, 131 {NULL} 132 #endif /* NETGRAPH_DEBUG */ 133 }; 134 135 struct ng_hook ng_deadhook = { 136 "dead", 137 NULL, /* private */ 138 HK_INVALID | HK_DEAD, 139 1, /* refs always >= 1 */ 140 &ng_deadhook, /* Peer is self */ 141 &ng_deadnode, /* attached to deadnode */ 142 {}, /* hooks list */ 143 NULL, /* override rcvmsg() */ 144 NULL, /* override rcvdata() */ 145 #ifdef NETGRAPH_DEBUG 146 HK_MAGIC, 147 __FILE__, 148 __LINE__, 149 {NULL} 150 #endif /* NETGRAPH_DEBUG */ 151 }; 152 153 /* 154 * END DEAD STRUCTURES 155 */ 156 /* List nodes with unallocated work */ 157 static TAILQ_HEAD(, ng_node) ng_worklist = TAILQ_HEAD_INITIALIZER(ng_worklist); 158 static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */ 159 160 /* List of installed types */ 161 static LIST_HEAD(, ng_type) ng_typelist; 162 static struct mtx ng_typelist_mtx; 163 164 /* Hash related definitions */ 165 /* XXX Don't need to initialise them because it's a LIST */ 166 #define NG_ID_HASH_SIZE 32 /* most systems wont need even this many */ 167 static LIST_HEAD(, ng_node) ng_ID_hash[NG_ID_HASH_SIZE]; 168 static struct mtx ng_idhash_mtx; 169 /* Method to find a node.. used twice so do it here */ 170 #define NG_IDHASH_FN(ID) ((ID) % (NG_ID_HASH_SIZE)) 171 #define NG_IDHASH_FIND(ID, node) \ 172 do { \ 173 mtx_assert(&ng_idhash_mtx, MA_OWNED); \ 174 LIST_FOREACH(node, &ng_ID_hash[NG_IDHASH_FN(ID)], \ 175 nd_idnodes) { \ 176 if (NG_NODE_IS_VALID(node) \ 177 && (NG_NODE_ID(node) == ID)) { \ 178 break; \ 179 } \ 180 } \ 181 } while (0) 182 183 184 /* Internal functions */ 185 static int ng_add_hook(node_p node, const char *name, hook_p * hookp); 186 static int ng_generic_msg(node_p here, item_p item, hook_p lasthook); 187 static ng_ID_t ng_decodeidname(const char *name); 188 static int ngb_mod_event(module_t mod, int event, void *data); 189 static void ng_worklist_remove(node_p node); 190 static void ngintr(void); 191 static int ng_apply_item(node_p node, item_p item); 192 static void ng_flush_input_queue(struct ng_queue * ngq); 193 static void ng_setisr(node_p node); 194 static node_p ng_ID2noderef(ng_ID_t ID); 195 static int ng_con_nodes(node_p node, const char *name, node_p node2, 196 const char *name2); 197 static void ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2); 198 static void ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2); 199 static int ng_mkpeer(node_p node, const char *name, 200 const char *name2, char *type); 201 202 /* imported , these used to be externally visible, some may go back */ 203 void ng_destroy_hook(hook_p hook); 204 node_p ng_name2noderef(node_p node, const char *name); 205 int ng_path2noderef(node_p here, const char *path, 206 node_p *dest, hook_p *lasthook); 207 int ng_make_node(const char *type, node_p *nodepp); 208 int ng_path_parse(char *addr, char **node, char **path, char **hook); 209 void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3); 210 void ng_unname(node_p node); 211 212 213 /* Our own netgraph malloc type */ 214 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages"); 215 MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures"); 216 MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures"); 217 MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", "netgraph item structures"); 218 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage"); 219 220 /* Should not be visible outside this file */ 221 222 #define _NG_ALLOC_HOOK(hook) \ 223 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO) 224 #define _NG_ALLOC_NODE(node) \ 225 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO) 226 227 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/ 228 /* 229 * In debug mode: 230 * In an attempt to help track reference count screwups 231 * we do not free objects back to the malloc system, but keep them 232 * in a local cache where we can examine them and keep information safely 233 * after they have been freed. 234 * We use this scheme for nodes and hooks, and to some extent for items. 235 */ 236 static __inline hook_p 237 ng_alloc_hook(void) 238 { 239 hook_p hook; 240 SLIST_ENTRY(ng_hook) temp; 241 mtx_lock(&ng_nodelist_mtx); 242 hook = LIST_FIRST(&ng_freehooks); 243 if (hook) { 244 LIST_REMOVE(hook, hk_hooks); 245 bcopy(&hook->hk_all, &temp, sizeof(temp)); 246 bzero(hook, sizeof(struct ng_hook)); 247 bcopy(&temp, &hook->hk_all, sizeof(temp)); 248 mtx_unlock(&ng_nodelist_mtx); 249 hook->hk_magic = HK_MAGIC; 250 } else { 251 mtx_unlock(&ng_nodelist_mtx); 252 _NG_ALLOC_HOOK(hook); 253 if (hook) { 254 hook->hk_magic = HK_MAGIC; 255 mtx_lock(&ng_nodelist_mtx); 256 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all); 257 mtx_unlock(&ng_nodelist_mtx); 258 } 259 } 260 return (hook); 261 } 262 263 static __inline node_p 264 ng_alloc_node(void) 265 { 266 node_p node; 267 SLIST_ENTRY(ng_node) temp; 268 mtx_lock(&ng_nodelist_mtx); 269 node = LIST_FIRST(&ng_freenodes); 270 if (node) { 271 LIST_REMOVE(node, nd_nodes); 272 bcopy(&node->nd_all, &temp, sizeof(temp)); 273 bzero(node, sizeof(struct ng_node)); 274 bcopy(&temp, &node->nd_all, sizeof(temp)); 275 mtx_unlock(&ng_nodelist_mtx); 276 node->nd_magic = ND_MAGIC; 277 } else { 278 mtx_unlock(&ng_nodelist_mtx); 279 _NG_ALLOC_NODE(node); 280 if (node) { 281 node->nd_magic = ND_MAGIC; 282 mtx_lock(&ng_nodelist_mtx); 283 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all); 284 mtx_unlock(&ng_nodelist_mtx); 285 } 286 } 287 return (node); 288 } 289 290 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0) 291 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0) 292 293 294 #define NG_FREE_HOOK(hook) \ 295 do { \ 296 mtx_lock(&ng_nodelist_mtx); \ 297 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \ 298 hook->hk_magic = 0; \ 299 mtx_unlock(&ng_nodelist_mtx); \ 300 } while (0) 301 302 #define NG_FREE_NODE(node) \ 303 do { \ 304 mtx_lock(&ng_nodelist_mtx); \ 305 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \ 306 node->nd_magic = 0; \ 307 mtx_unlock(&ng_nodelist_mtx); \ 308 } while (0) 309 310 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 311 312 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook) 313 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node) 314 315 #define NG_FREE_HOOK(hook) do { FREE((hook), M_NETGRAPH_HOOK); } while (0) 316 #define NG_FREE_NODE(node) do { FREE((node), M_NETGRAPH_NODE); } while (0) 317 318 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 319 320 /* Warning: Generally use NG_FREE_ITEM() instead */ 321 #define NG_FREE_ITEM_REAL(item) do { FREE((item), M_NETGRAPH_ITEM); } while (0) 322 323 324 /* Set this to kdb_enter("X") to catch all errors as they occur */ 325 #ifndef TRAP_ERROR 326 #define TRAP_ERROR() 327 #endif 328 329 static ng_ID_t nextID = 1; 330 331 #ifdef INVARIANTS 332 #define CHECK_DATA_MBUF(m) do { \ 333 struct mbuf *n; \ 334 int total; \ 335 \ 336 M_ASSERTPKTHDR(m); \ 337 for (total = 0, n = (m); n != NULL; n = n->m_next) \ 338 total += n->m_len; \ 339 if ((m)->m_pkthdr.len != total) { \ 340 panic("%s: %d != %d", \ 341 __func__, (m)->m_pkthdr.len, total); \ 342 } \ 343 } while (0) 344 #else 345 #define CHECK_DATA_MBUF(m) 346 #endif 347 348 349 /************************************************************************ 350 Parse type definitions for generic messages 351 ************************************************************************/ 352 353 /* Handy structure parse type defining macro */ 354 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \ 355 static const struct ng_parse_struct_field \ 356 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \ 357 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \ 358 &ng_parse_struct_type, \ 359 &ng_ ## lo ## _type_fields \ 360 } 361 362 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ()); 363 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ()); 364 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ()); 365 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ()); 366 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ()); 367 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ()); 368 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type)); 369 370 /* Get length of an array when the length is stored as a 32 bit 371 value immediately preceding the array -- as with struct namelist 372 and struct typelist. */ 373 static int 374 ng_generic_list_getLength(const struct ng_parse_type *type, 375 const u_char *start, const u_char *buf) 376 { 377 return *((const u_int32_t *)(buf - 4)); 378 } 379 380 /* Get length of the array of struct linkinfo inside a struct hooklist */ 381 static int 382 ng_generic_linkinfo_getLength(const struct ng_parse_type *type, 383 const u_char *start, const u_char *buf) 384 { 385 const struct hooklist *hl = (const struct hooklist *)start; 386 387 return hl->nodeinfo.hooks; 388 } 389 390 /* Array type for a variable length array of struct namelist */ 391 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = { 392 &ng_generic_nodeinfo_type, 393 &ng_generic_list_getLength 394 }; 395 static const struct ng_parse_type ng_generic_nodeinfoarray_type = { 396 &ng_parse_array_type, 397 &ng_nodeinfoarray_type_info 398 }; 399 400 /* Array type for a variable length array of struct typelist */ 401 static const struct ng_parse_array_info ng_typeinfoarray_type_info = { 402 &ng_generic_typeinfo_type, 403 &ng_generic_list_getLength 404 }; 405 static const struct ng_parse_type ng_generic_typeinfoarray_type = { 406 &ng_parse_array_type, 407 &ng_typeinfoarray_type_info 408 }; 409 410 /* Array type for array of struct linkinfo in struct hooklist */ 411 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = { 412 &ng_generic_linkinfo_type, 413 &ng_generic_linkinfo_getLength 414 }; 415 static const struct ng_parse_type ng_generic_linkinfo_array_type = { 416 &ng_parse_array_type, 417 &ng_generic_linkinfo_array_type_info 418 }; 419 420 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type)); 421 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST, 422 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type)); 423 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES, 424 (&ng_generic_nodeinfoarray_type)); 425 426 /* List of commands and how to convert arguments to/from ASCII */ 427 static const struct ng_cmdlist ng_generic_cmds[] = { 428 { 429 NGM_GENERIC_COOKIE, 430 NGM_SHUTDOWN, 431 "shutdown", 432 NULL, 433 NULL 434 }, 435 { 436 NGM_GENERIC_COOKIE, 437 NGM_MKPEER, 438 "mkpeer", 439 &ng_generic_mkpeer_type, 440 NULL 441 }, 442 { 443 NGM_GENERIC_COOKIE, 444 NGM_CONNECT, 445 "connect", 446 &ng_generic_connect_type, 447 NULL 448 }, 449 { 450 NGM_GENERIC_COOKIE, 451 NGM_NAME, 452 "name", 453 &ng_generic_name_type, 454 NULL 455 }, 456 { 457 NGM_GENERIC_COOKIE, 458 NGM_RMHOOK, 459 "rmhook", 460 &ng_generic_rmhook_type, 461 NULL 462 }, 463 { 464 NGM_GENERIC_COOKIE, 465 NGM_NODEINFO, 466 "nodeinfo", 467 NULL, 468 &ng_generic_nodeinfo_type 469 }, 470 { 471 NGM_GENERIC_COOKIE, 472 NGM_LISTHOOKS, 473 "listhooks", 474 NULL, 475 &ng_generic_hooklist_type 476 }, 477 { 478 NGM_GENERIC_COOKIE, 479 NGM_LISTNAMES, 480 "listnames", 481 NULL, 482 &ng_generic_listnodes_type /* same as NGM_LISTNODES */ 483 }, 484 { 485 NGM_GENERIC_COOKIE, 486 NGM_LISTNODES, 487 "listnodes", 488 NULL, 489 &ng_generic_listnodes_type 490 }, 491 { 492 NGM_GENERIC_COOKIE, 493 NGM_LISTTYPES, 494 "listtypes", 495 NULL, 496 &ng_generic_typeinfo_type 497 }, 498 { 499 NGM_GENERIC_COOKIE, 500 NGM_TEXT_CONFIG, 501 "textconfig", 502 NULL, 503 &ng_parse_string_type 504 }, 505 { 506 NGM_GENERIC_COOKIE, 507 NGM_TEXT_STATUS, 508 "textstatus", 509 NULL, 510 &ng_parse_string_type 511 }, 512 { 513 NGM_GENERIC_COOKIE, 514 NGM_ASCII2BINARY, 515 "ascii2binary", 516 &ng_parse_ng_mesg_type, 517 &ng_parse_ng_mesg_type 518 }, 519 { 520 NGM_GENERIC_COOKIE, 521 NGM_BINARY2ASCII, 522 "binary2ascii", 523 &ng_parse_ng_mesg_type, 524 &ng_parse_ng_mesg_type 525 }, 526 { 0 } 527 }; 528 529 /************************************************************************ 530 Node routines 531 ************************************************************************/ 532 533 /* 534 * Instantiate a node of the requested type 535 */ 536 int 537 ng_make_node(const char *typename, node_p *nodepp) 538 { 539 struct ng_type *type; 540 int error; 541 542 /* Check that the type makes sense */ 543 if (typename == NULL) { 544 TRAP_ERROR(); 545 return (EINVAL); 546 } 547 548 /* Locate the node type. If we fail we return. Do not try to load 549 * module. 550 */ 551 if ((type = ng_findtype(typename)) == NULL) 552 return (ENXIO); 553 554 /* 555 * If we have a constructor, then make the node and 556 * call the constructor to do type specific initialisation. 557 */ 558 if (type->constructor != NULL) { 559 if ((error = ng_make_node_common(type, nodepp)) == 0) { 560 if ((error = ((*type->constructor)(*nodepp)) != 0)) { 561 NG_NODE_UNREF(*nodepp); 562 } 563 } 564 } else { 565 /* 566 * Node has no constructor. We cannot ask for one 567 * to be made. It must be brought into existance by 568 * some external agency. The external agency should 569 * call ng_make_node_common() directly to get the 570 * netgraph part initialised. 571 */ 572 TRAP_ERROR(); 573 error = EINVAL; 574 } 575 return (error); 576 } 577 578 /* 579 * Generic node creation. Called by node initialisation for externally 580 * instantiated nodes (e.g. hardware, sockets, etc ). 581 * The returned node has a reference count of 1. 582 */ 583 int 584 ng_make_node_common(struct ng_type *type, node_p *nodepp) 585 { 586 node_p node; 587 588 /* Require the node type to have been already installed */ 589 if (ng_findtype(type->name) == NULL) { 590 TRAP_ERROR(); 591 return (EINVAL); 592 } 593 594 /* Make a node and try attach it to the type */ 595 NG_ALLOC_NODE(node); 596 if (node == NULL) { 597 TRAP_ERROR(); 598 return (ENOMEM); 599 } 600 node->nd_type = type; 601 NG_NODE_REF(node); /* note reference */ 602 type->refs++; 603 604 mtx_init(&node->nd_input_queue.q_mtx, "ng_node", NULL, MTX_SPIN); 605 node->nd_input_queue.queue = NULL; 606 node->nd_input_queue.last = &node->nd_input_queue.queue; 607 node->nd_input_queue.q_flags = 0; 608 node->nd_input_queue.q_node = node; 609 610 /* Initialize hook list for new node */ 611 LIST_INIT(&node->nd_hooks); 612 613 /* Link us into the node linked list */ 614 mtx_lock(&ng_nodelist_mtx); 615 LIST_INSERT_HEAD(&ng_nodelist, node, nd_nodes); 616 mtx_unlock(&ng_nodelist_mtx); 617 618 619 /* get an ID and put us in the hash chain */ 620 mtx_lock(&ng_idhash_mtx); 621 for (;;) { /* wrap protection, even if silly */ 622 node_p node2 = NULL; 623 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */ 624 625 /* Is there a problem with the new number? */ 626 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */ 627 if ((node->nd_ID != 0) && (node2 == NULL)) { 628 break; 629 } 630 } 631 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)], 632 node, nd_idnodes); 633 mtx_unlock(&ng_idhash_mtx); 634 635 /* Done */ 636 *nodepp = node; 637 return (0); 638 } 639 640 /* 641 * Forceably start the shutdown process on a node. Either call 642 * it's shutdown method, or do the default shutdown if there is 643 * no type-specific method. 644 * 645 * We can only be called form a shutdown message, so we know we have 646 * a writer lock, and therefore exclusive access. It also means 647 * that we should not be on the work queue, but we check anyhow. 648 * 649 * Persistent node types must have a type-specific method which 650 * Allocates a new node in which case, this one is irretrievably going away, 651 * or cleans up anything it needs, and just makes the node valid again, 652 * in which case we allow the node to survive. 653 * 654 * XXX We need to think of how to tell a persistant node that we 655 * REALLY need to go away because the hardware has gone or we 656 * are rebooting.... etc. 657 */ 658 void 659 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3) 660 { 661 hook_p hook; 662 663 /* Check if it's already shutting down */ 664 if ((node->nd_flags & NGF_CLOSING) != 0) 665 return; 666 667 if (node == &ng_deadnode) { 668 printf ("shutdown called on deadnode\n"); 669 return; 670 } 671 672 /* Add an extra reference so it doesn't go away during this */ 673 NG_NODE_REF(node); 674 675 /* 676 * Mark it invalid so any newcomers know not to try use it 677 * Also add our own mark so we can't recurse 678 * note that NGF_INVALID does not do this as it's also set during 679 * creation 680 */ 681 node->nd_flags |= NGF_INVALID|NGF_CLOSING; 682 683 /* If node has its pre-shutdown method, then call it first*/ 684 if (node->nd_type && node->nd_type->close) 685 (*node->nd_type->close)(node); 686 687 /* Notify all remaining connected nodes to disconnect */ 688 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL) 689 ng_destroy_hook(hook); 690 691 /* 692 * Drain the input queue forceably. 693 * it has no hooks so what's it going to do, bleed on someone? 694 * Theoretically we came here from a queue entry that was added 695 * Just before the queue was closed, so it should be empty anyway. 696 * Also removes us from worklist if needed. 697 */ 698 ng_flush_input_queue(&node->nd_input_queue); 699 700 /* Ask the type if it has anything to do in this case */ 701 if (node->nd_type && node->nd_type->shutdown) { 702 (*node->nd_type->shutdown)(node); 703 if (NG_NODE_IS_VALID(node)) { 704 /* 705 * Well, blow me down if the node code hasn't declared 706 * that it doesn't want to die. 707 * Presumably it is a persistant node. 708 * If we REALLY want it to go away, 709 * e.g. hardware going away, 710 * Our caller should set NGF_REALLY_DIE in nd_flags. 711 */ 712 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING); 713 NG_NODE_UNREF(node); /* Assume they still have theirs */ 714 return; 715 } 716 } else { /* do the default thing */ 717 NG_NODE_UNREF(node); 718 } 719 720 ng_unname(node); /* basically a NOP these days */ 721 722 /* 723 * Remove extra reference, possibly the last 724 * Possible other holders of references may include 725 * timeout callouts, but theoretically the node's supposed to 726 * have cancelled them. Possibly hardware dependencies may 727 * force a driver to 'linger' with a reference. 728 */ 729 NG_NODE_UNREF(node); 730 } 731 732 #ifdef NETGRAPH_DEBUG 733 void 734 ng_ref_node(node_p node) 735 { 736 _NG_NODE_REF(node); 737 } 738 #endif 739 740 /* 741 * Remove a reference to the node, possibly the last. 742 * deadnode always acts as it it were the last. 743 */ 744 int 745 ng_unref_node(node_p node) 746 { 747 int v; 748 749 if (node == &ng_deadnode) { 750 return (0); 751 } 752 753 do { 754 v = node->nd_refs - 1; 755 } while (! atomic_cmpset_int(&node->nd_refs, v + 1, v)); 756 757 if (v == 0) { /* we were the last */ 758 759 mtx_lock(&ng_nodelist_mtx); 760 node->nd_type->refs--; /* XXX maybe should get types lock? */ 761 LIST_REMOVE(node, nd_nodes); 762 mtx_unlock(&ng_nodelist_mtx); 763 764 mtx_lock(&ng_idhash_mtx); 765 LIST_REMOVE(node, nd_idnodes); 766 mtx_unlock(&ng_idhash_mtx); 767 768 mtx_destroy(&node->nd_input_queue.q_mtx); 769 NG_FREE_NODE(node); 770 } 771 return (v); 772 } 773 774 /************************************************************************ 775 Node ID handling 776 ************************************************************************/ 777 static node_p 778 ng_ID2noderef(ng_ID_t ID) 779 { 780 node_p node; 781 mtx_lock(&ng_idhash_mtx); 782 NG_IDHASH_FIND(ID, node); 783 if(node) 784 NG_NODE_REF(node); 785 mtx_unlock(&ng_idhash_mtx); 786 return(node); 787 } 788 789 ng_ID_t 790 ng_node2ID(node_p node) 791 { 792 return (node ? NG_NODE_ID(node) : 0); 793 } 794 795 /************************************************************************ 796 Node name handling 797 ************************************************************************/ 798 799 /* 800 * Assign a node a name. Once assigned, the name cannot be changed. 801 */ 802 int 803 ng_name_node(node_p node, const char *name) 804 { 805 int i; 806 node_p node2; 807 808 /* Check the name is valid */ 809 for (i = 0; i < NG_NODESIZ; i++) { 810 if (name[i] == '\0' || name[i] == '.' || name[i] == ':') 811 break; 812 } 813 if (i == 0 || name[i] != '\0') { 814 TRAP_ERROR(); 815 return (EINVAL); 816 } 817 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */ 818 TRAP_ERROR(); 819 return (EINVAL); 820 } 821 822 /* Check the name isn't already being used */ 823 if ((node2 = ng_name2noderef(node, name)) != NULL) { 824 NG_NODE_UNREF(node2); 825 TRAP_ERROR(); 826 return (EADDRINUSE); 827 } 828 829 /* copy it */ 830 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ); 831 832 return (0); 833 } 834 835 /* 836 * Find a node by absolute name. The name should NOT end with ':' 837 * The name "." means "this node" and "[xxx]" means "the node 838 * with ID (ie, at address) xxx". 839 * 840 * Returns the node if found, else NULL. 841 * Eventually should add something faster than a sequential search. 842 * Note it aquires a reference on the node so you can be sure it's still there. 843 */ 844 node_p 845 ng_name2noderef(node_p here, const char *name) 846 { 847 node_p node; 848 ng_ID_t temp; 849 850 /* "." means "this node" */ 851 if (strcmp(name, ".") == 0) { 852 NG_NODE_REF(here); 853 return(here); 854 } 855 856 /* Check for name-by-ID */ 857 if ((temp = ng_decodeidname(name)) != 0) { 858 return (ng_ID2noderef(temp)); 859 } 860 861 /* Find node by name */ 862 mtx_lock(&ng_nodelist_mtx); 863 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 864 if (NG_NODE_IS_VALID(node) 865 && NG_NODE_HAS_NAME(node) 866 && (strcmp(NG_NODE_NAME(node), name) == 0)) { 867 break; 868 } 869 } 870 if (node) 871 NG_NODE_REF(node); 872 mtx_unlock(&ng_nodelist_mtx); 873 return (node); 874 } 875 876 /* 877 * Decode an ID name, eg. "[f03034de]". Returns 0 if the 878 * string is not valid, otherwise returns the value. 879 */ 880 static ng_ID_t 881 ng_decodeidname(const char *name) 882 { 883 const int len = strlen(name); 884 char *eptr; 885 u_long val; 886 887 /* Check for proper length, brackets, no leading junk */ 888 if ((len < 3) 889 || (name[0] != '[') 890 || (name[len - 1] != ']') 891 || (!isxdigit(name[1]))) { 892 return ((ng_ID_t)0); 893 } 894 895 /* Decode number */ 896 val = strtoul(name + 1, &eptr, 16); 897 if ((eptr - name != len - 1) 898 || (val == ULONG_MAX) 899 || (val == 0)) { 900 return ((ng_ID_t)0); 901 } 902 return (ng_ID_t)val; 903 } 904 905 /* 906 * Remove a name from a node. This should only be called 907 * when shutting down and removing the node. 908 * IF we allow name changing this may be more resurected. 909 */ 910 void 911 ng_unname(node_p node) 912 { 913 } 914 915 /************************************************************************ 916 Hook routines 917 Names are not optional. Hooks are always connected, except for a 918 brief moment within these routines. On invalidation or during creation 919 they are connected to the 'dead' hook. 920 ************************************************************************/ 921 922 /* 923 * Remove a hook reference 924 */ 925 void 926 ng_unref_hook(hook_p hook) 927 { 928 int v; 929 930 if (hook == &ng_deadhook) { 931 return; 932 } 933 do { 934 v = hook->hk_refs; 935 } while (! atomic_cmpset_int(&hook->hk_refs, v, v - 1)); 936 937 if (v == 1) { /* we were the last */ 938 if (_NG_HOOK_NODE(hook)) { /* it'll probably be ng_deadnode */ 939 _NG_NODE_UNREF((_NG_HOOK_NODE(hook))); 940 hook->hk_node = NULL; 941 } 942 NG_FREE_HOOK(hook); 943 } 944 } 945 946 /* 947 * Add an unconnected hook to a node. Only used internally. 948 * Assumes node is locked. (XXX not yet true ) 949 */ 950 static int 951 ng_add_hook(node_p node, const char *name, hook_p *hookp) 952 { 953 hook_p hook; 954 int error = 0; 955 956 /* Check that the given name is good */ 957 if (name == NULL) { 958 TRAP_ERROR(); 959 return (EINVAL); 960 } 961 if (ng_findhook(node, name) != NULL) { 962 TRAP_ERROR(); 963 return (EEXIST); 964 } 965 966 /* Allocate the hook and link it up */ 967 NG_ALLOC_HOOK(hook); 968 if (hook == NULL) { 969 TRAP_ERROR(); 970 return (ENOMEM); 971 } 972 hook->hk_refs = 1; /* add a reference for us to return */ 973 hook->hk_flags = HK_INVALID; 974 hook->hk_peer = &ng_deadhook; /* start off this way */ 975 hook->hk_node = node; 976 NG_NODE_REF(node); /* each hook counts as a reference */ 977 978 /* Set hook name */ 979 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ); 980 981 /* 982 * Check if the node type code has something to say about it 983 * If it fails, the unref of the hook will also unref the node. 984 */ 985 if (node->nd_type->newhook != NULL) { 986 if ((error = (*node->nd_type->newhook)(node, hook, name))) { 987 NG_HOOK_UNREF(hook); /* this frees the hook */ 988 return (error); 989 } 990 } 991 /* 992 * The 'type' agrees so far, so go ahead and link it in. 993 * We'll ask again later when we actually connect the hooks. 994 */ 995 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 996 node->nd_numhooks++; 997 NG_HOOK_REF(hook); /* one for the node */ 998 999 if (hookp) 1000 *hookp = hook; 1001 return (0); 1002 } 1003 1004 /* 1005 * Find a hook 1006 * 1007 * Node types may supply their own optimized routines for finding 1008 * hooks. If none is supplied, we just do a linear search. 1009 * XXX Possibly we should add a reference to the hook? 1010 */ 1011 hook_p 1012 ng_findhook(node_p node, const char *name) 1013 { 1014 hook_p hook; 1015 1016 if (node->nd_type->findhook != NULL) 1017 return (*node->nd_type->findhook)(node, name); 1018 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) { 1019 if (NG_HOOK_IS_VALID(hook) 1020 && (strcmp(NG_HOOK_NAME(hook), name) == 0)) 1021 return (hook); 1022 } 1023 return (NULL); 1024 } 1025 1026 /* 1027 * Destroy a hook 1028 * 1029 * As hooks are always attached, this really destroys two hooks. 1030 * The one given, and the one attached to it. Disconnect the hooks 1031 * from each other first. We reconnect the peer hook to the 'dead' 1032 * hook so that it can still exist after we depart. We then 1033 * send the peer its own destroy message. This ensures that we only 1034 * interact with the peer's structures when it is locked processing that 1035 * message. We hold a reference to the peer hook so we are guaranteed that 1036 * the peer hook and node are still going to exist until 1037 * we are finished there as the hook holds a ref on the node. 1038 * We run this same code again on the peer hook, but that time it is already 1039 * attached to the 'dead' hook. 1040 * 1041 * This routine is called at all stages of hook creation 1042 * on error detection and must be able to handle any such stage. 1043 */ 1044 void 1045 ng_destroy_hook(hook_p hook) 1046 { 1047 hook_p peer = NG_HOOK_PEER(hook); 1048 node_p node = NG_HOOK_NODE(hook); 1049 1050 if (hook == &ng_deadhook) { /* better safe than sorry */ 1051 printf("ng_destroy_hook called on deadhook\n"); 1052 return; 1053 } 1054 hook->hk_flags |= HK_INVALID; /* as soon as possible */ 1055 if (peer && (peer != &ng_deadhook)) { 1056 /* 1057 * Set the peer to point to ng_deadhook 1058 * from this moment on we are effectively independent it. 1059 * send it an rmhook message of it's own. 1060 */ 1061 peer->hk_peer = &ng_deadhook; /* They no longer know us */ 1062 hook->hk_peer = &ng_deadhook; /* Nor us, them */ 1063 if (NG_HOOK_NODE(peer) == &ng_deadnode) { 1064 /* 1065 * If it's already divorced from a node, 1066 * just free it. 1067 */ 1068 /* nothing */ 1069 } else { 1070 ng_rmhook_self(peer); /* Send it a surprise */ 1071 } 1072 NG_HOOK_UNREF(peer); /* account for peer link */ 1073 NG_HOOK_UNREF(hook); /* account for peer link */ 1074 } 1075 1076 /* 1077 * Remove the hook from the node's list to avoid possible recursion 1078 * in case the disconnection results in node shutdown. 1079 */ 1080 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */ 1081 return; 1082 } 1083 LIST_REMOVE(hook, hk_hooks); 1084 node->nd_numhooks--; 1085 if (node->nd_type->disconnect) { 1086 /* 1087 * The type handler may elect to destroy the node so don't 1088 * trust its existance after this point. (except 1089 * that we still hold a reference on it. (which we 1090 * inherrited from the hook we are destroying) 1091 */ 1092 (*node->nd_type->disconnect) (hook); 1093 } 1094 1095 /* 1096 * Note that because we will point to ng_deadnode, the original node 1097 * is not decremented automatically so we do that manually. 1098 */ 1099 _NG_HOOK_NODE(hook) = &ng_deadnode; 1100 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */ 1101 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */ 1102 } 1103 1104 /* 1105 * Take two hooks on a node and merge the connection so that the given node 1106 * is effectively bypassed. 1107 */ 1108 int 1109 ng_bypass(hook_p hook1, hook_p hook2) 1110 { 1111 if (hook1->hk_node != hook2->hk_node) { 1112 TRAP_ERROR(); 1113 return (EINVAL); 1114 } 1115 hook1->hk_peer->hk_peer = hook2->hk_peer; 1116 hook2->hk_peer->hk_peer = hook1->hk_peer; 1117 1118 hook1->hk_peer = &ng_deadhook; 1119 hook2->hk_peer = &ng_deadhook; 1120 1121 /* XXX If we ever cache methods on hooks update them as well */ 1122 ng_destroy_hook(hook1); 1123 ng_destroy_hook(hook2); 1124 return (0); 1125 } 1126 1127 /* 1128 * Install a new netgraph type 1129 */ 1130 int 1131 ng_newtype(struct ng_type *tp) 1132 { 1133 const size_t namelen = strlen(tp->name); 1134 1135 /* Check version and type name fields */ 1136 if ((tp->version != NG_ABI_VERSION) 1137 || (namelen == 0) 1138 || (namelen >= NG_TYPESIZ)) { 1139 TRAP_ERROR(); 1140 if (tp->version != NG_ABI_VERSION) { 1141 printf("Netgraph: Node type rejected. ABI mismatch. Suggest recompile\n"); 1142 } 1143 return (EINVAL); 1144 } 1145 1146 /* Check for name collision */ 1147 if (ng_findtype(tp->name) != NULL) { 1148 TRAP_ERROR(); 1149 return (EEXIST); 1150 } 1151 1152 1153 /* Link in new type */ 1154 mtx_lock(&ng_typelist_mtx); 1155 LIST_INSERT_HEAD(&ng_typelist, tp, types); 1156 tp->refs = 1; /* first ref is linked list */ 1157 mtx_unlock(&ng_typelist_mtx); 1158 return (0); 1159 } 1160 1161 /* 1162 * unlink a netgraph type 1163 * If no examples exist 1164 */ 1165 int 1166 ng_rmtype(struct ng_type *tp) 1167 { 1168 /* Check for name collision */ 1169 if (tp->refs != 1) { 1170 TRAP_ERROR(); 1171 return (EBUSY); 1172 } 1173 1174 /* Unlink type */ 1175 mtx_lock(&ng_typelist_mtx); 1176 LIST_REMOVE(tp, types); 1177 mtx_unlock(&ng_typelist_mtx); 1178 return (0); 1179 } 1180 1181 /* 1182 * Look for a type of the name given 1183 */ 1184 struct ng_type * 1185 ng_findtype(const char *typename) 1186 { 1187 struct ng_type *type; 1188 1189 mtx_lock(&ng_typelist_mtx); 1190 LIST_FOREACH(type, &ng_typelist, types) { 1191 if (strcmp(type->name, typename) == 0) 1192 break; 1193 } 1194 mtx_unlock(&ng_typelist_mtx); 1195 return (type); 1196 } 1197 1198 /************************************************************************ 1199 Composite routines 1200 ************************************************************************/ 1201 /* 1202 * Connect two nodes using the specified hooks, using queued functions. 1203 */ 1204 static void 1205 ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2) 1206 { 1207 1208 /* 1209 * When we run, we know that the node 'node' is locked for us. 1210 * Our caller has a reference on the hook. 1211 * Our caller has a reference on the node. 1212 * (In this case our caller is ng_apply_item() ). 1213 * The peer hook has a reference on the hook. 1214 * We are all set up except for the final call to the node, and 1215 * the clearing of the INVALID flag. 1216 */ 1217 if (NG_HOOK_NODE(hook) == &ng_deadnode) { 1218 /* 1219 * The node must have been freed again since we last visited 1220 * here. ng_destry_hook() has this effect but nothing else does. 1221 * We should just release our references and 1222 * free anything we can think of. 1223 * Since we know it's been destroyed, and it's our caller 1224 * that holds the references, just return. 1225 */ 1226 return ; 1227 } 1228 if (hook->hk_node->nd_type->connect) { 1229 if ((*hook->hk_node->nd_type->connect) (hook)) { 1230 ng_destroy_hook(hook); /* also zaps peer */ 1231 printf("failed in ng_con_part3()\n"); 1232 return ; 1233 } 1234 } 1235 /* 1236 * XXX this is wrong for SMP. Possibly we need 1237 * to separate out 'create' and 'invalid' flags. 1238 * should only set flags on hooks we have locked under our node. 1239 */ 1240 hook->hk_flags &= ~HK_INVALID; 1241 return ; 1242 } 1243 1244 static void 1245 ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2) 1246 { 1247 1248 /* 1249 * When we run, we know that the node 'node' is locked for us. 1250 * Our caller has a reference on the hook. 1251 * Our caller has a reference on the node. 1252 * (In this case our caller is ng_apply_item() ). 1253 * The peer hook has a reference on the hook. 1254 * our node pointer points to the 'dead' node. 1255 * First check the hook name is unique. 1256 * Should not happen because we checked before queueing this. 1257 */ 1258 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) { 1259 TRAP_ERROR(); 1260 ng_destroy_hook(hook); /* should destroy peer too */ 1261 printf("failed in ng_con_part2()\n"); 1262 return ; 1263 } 1264 /* 1265 * Check if the node type code has something to say about it 1266 * If it fails, the unref of the hook will also unref the attached node, 1267 * however since that node is 'ng_deadnode' this will do nothing. 1268 * The peer hook will also be destroyed. 1269 */ 1270 if (node->nd_type->newhook != NULL) { 1271 if ((*node->nd_type->newhook)(node, hook, hook->hk_name)) { 1272 ng_destroy_hook(hook); /* should destroy peer too */ 1273 printf("failed in ng_con_part2()\n"); 1274 return ; 1275 } 1276 } 1277 1278 /* 1279 * The 'type' agrees so far, so go ahead and link it in. 1280 * We'll ask again later when we actually connect the hooks. 1281 */ 1282 hook->hk_node = node; /* just overwrite ng_deadnode */ 1283 NG_NODE_REF(node); /* each hook counts as a reference */ 1284 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1285 node->nd_numhooks++; 1286 NG_HOOK_REF(hook); /* one for the node */ 1287 1288 /* 1289 * We now have a symetrical situation, where both hooks have been 1290 * linked to their nodes, the newhook methods have been called 1291 * And the references are all correct. The hooks are still marked 1292 * as invalid, as we have not called the 'connect' methods 1293 * yet. 1294 * We can call the local one immediatly as we have the 1295 * node locked, but we need to queue the remote one. 1296 */ 1297 if (hook->hk_node->nd_type->connect) { 1298 if ((*hook->hk_node->nd_type->connect) (hook)) { 1299 ng_destroy_hook(hook); /* also zaps peer */ 1300 printf("failed in ng_con_part2(A)\n"); 1301 return ; 1302 } 1303 } 1304 if (ng_send_fn(hook->hk_peer->hk_node, hook->hk_peer, 1305 &ng_con_part3, arg1, arg2)) { 1306 printf("failed in ng_con_part2(B)"); 1307 ng_destroy_hook(hook); /* also zaps peer */ 1308 return ; 1309 } 1310 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */ 1311 return ; 1312 } 1313 1314 /* 1315 * Connect this node with another node. We assume that this node is 1316 * currently locked, as we are only called from an NGM_CONNECT message. 1317 */ 1318 static int 1319 ng_con_nodes(node_p node, const char *name, node_p node2, const char *name2) 1320 { 1321 int error; 1322 hook_p hook; 1323 hook_p hook2; 1324 1325 if (ng_findhook(node2, name2) != NULL) { 1326 return(EEXIST); 1327 } 1328 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */ 1329 return (error); 1330 /* Allocate the other hook and link it up */ 1331 NG_ALLOC_HOOK(hook2); 1332 if (hook == NULL) { 1333 TRAP_ERROR(); 1334 ng_destroy_hook(hook); /* XXX check ref counts so far */ 1335 NG_HOOK_UNREF(hook); /* including our ref */ 1336 return (ENOMEM); 1337 } 1338 hook2->hk_refs = 1; /* start with a reference for us. */ 1339 hook2->hk_flags = HK_INVALID; 1340 hook2->hk_peer = hook; /* Link the two together */ 1341 hook->hk_peer = hook2; 1342 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/ 1343 NG_HOOK_REF(hook2); 1344 hook2->hk_node = &ng_deadnode; 1345 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ); 1346 1347 /* 1348 * Queue the function above. 1349 * Procesing continues in that function in the lock context of 1350 * the other node. 1351 */ 1352 ng_send_fn(node2, hook2, &ng_con_part2, NULL, 0); 1353 1354 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */ 1355 NG_HOOK_UNREF(hook2); 1356 return (0); 1357 } 1358 1359 /* 1360 * Make a peer and connect. 1361 * We assume that the local node is locked. 1362 * The new node probably doesn't need a lock until 1363 * it has a hook, because it cannot really have any work until then, 1364 * but we should think about it a bit more. 1365 * 1366 * The problem may come if the other node also fires up 1367 * some hardware or a timer or some other source of activation, 1368 * also it may already get a command msg via it's ID. 1369 * 1370 * We could use the same method as ng_con_nodes() but we'd have 1371 * to add ability to remove the node when failing. (Not hard, just 1372 * make arg1 point to the node to remove). 1373 * Unless of course we just ignore failure to connect and leave 1374 * an unconnected node? 1375 */ 1376 static int 1377 ng_mkpeer(node_p node, const char *name, const char *name2, char *type) 1378 { 1379 node_p node2; 1380 hook_p hook1; 1381 hook_p hook2; 1382 int error; 1383 1384 if ((error = ng_make_node(type, &node2))) { 1385 return (error); 1386 } 1387 1388 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */ 1389 ng_rmnode(node2, NULL, NULL, 0); 1390 return (error); 1391 } 1392 1393 if ((error = ng_add_hook(node2, name2, &hook2))) { 1394 ng_rmnode(node2, NULL, NULL, 0); 1395 ng_destroy_hook(hook1); 1396 NG_HOOK_UNREF(hook1); 1397 return (error); 1398 } 1399 1400 /* 1401 * Actually link the two hooks together. 1402 */ 1403 hook1->hk_peer = hook2; 1404 hook2->hk_peer = hook1; 1405 1406 /* Each hook is referenced by the other */ 1407 NG_HOOK_REF(hook1); 1408 NG_HOOK_REF(hook2); 1409 1410 /* Give each node the opportunity to veto the pending connection */ 1411 if (hook1->hk_node->nd_type->connect) { 1412 error = (*hook1->hk_node->nd_type->connect) (hook1); 1413 } 1414 1415 if ((error == 0) && hook2->hk_node->nd_type->connect) { 1416 error = (*hook2->hk_node->nd_type->connect) (hook2); 1417 1418 } 1419 1420 /* 1421 * drop the references we were holding on the two hooks. 1422 */ 1423 if (error) { 1424 ng_destroy_hook(hook2); /* also zaps hook1 */ 1425 ng_rmnode(node2, NULL, NULL, 0); 1426 } else { 1427 /* As a last act, allow the hooks to be used */ 1428 hook1->hk_flags &= ~HK_INVALID; 1429 hook2->hk_flags &= ~HK_INVALID; 1430 } 1431 NG_HOOK_UNREF(hook1); 1432 NG_HOOK_UNREF(hook2); 1433 return (error); 1434 } 1435 1436 /************************************************************************ 1437 Utility routines to send self messages 1438 ************************************************************************/ 1439 1440 /* Shut this node down as soon as everyone is clear of it */ 1441 /* Should add arg "immediatly" to jump the queue */ 1442 int 1443 ng_rmnode_self(node_p node) 1444 { 1445 int error; 1446 1447 if (node == &ng_deadnode) 1448 return (0); 1449 node->nd_flags |= NGF_INVALID; 1450 if (node->nd_flags & NGF_CLOSING) 1451 return (0); 1452 1453 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0); 1454 return (error); 1455 } 1456 1457 static void 1458 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2) 1459 { 1460 ng_destroy_hook(hook); 1461 return ; 1462 } 1463 1464 int 1465 ng_rmhook_self(hook_p hook) 1466 { 1467 int error; 1468 node_p node = NG_HOOK_NODE(hook); 1469 1470 if (node == &ng_deadnode) 1471 return (0); 1472 1473 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0); 1474 return (error); 1475 } 1476 1477 /*********************************************************************** 1478 * Parse and verify a string of the form: <NODE:><PATH> 1479 * 1480 * Such a string can refer to a specific node or a specific hook 1481 * on a specific node, depending on how you look at it. In the 1482 * latter case, the PATH component must not end in a dot. 1483 * 1484 * Both <NODE:> and <PATH> are optional. The <PATH> is a string 1485 * of hook names separated by dots. This breaks out the original 1486 * string, setting *nodep to "NODE" (or NULL if none) and *pathp 1487 * to "PATH" (or NULL if degenerate). Also, *hookp will point to 1488 * the final hook component of <PATH>, if any, otherwise NULL. 1489 * 1490 * This returns -1 if the path is malformed. The char ** are optional. 1491 ***********************************************************************/ 1492 int 1493 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp) 1494 { 1495 char *node, *path, *hook; 1496 int k; 1497 1498 /* 1499 * Extract absolute NODE, if any 1500 */ 1501 for (path = addr; *path && *path != ':'; path++); 1502 if (*path) { 1503 node = addr; /* Here's the NODE */ 1504 *path++ = '\0'; /* Here's the PATH */ 1505 1506 /* Node name must not be empty */ 1507 if (!*node) 1508 return -1; 1509 1510 /* A name of "." is OK; otherwise '.' not allowed */ 1511 if (strcmp(node, ".") != 0) { 1512 for (k = 0; node[k]; k++) 1513 if (node[k] == '.') 1514 return -1; 1515 } 1516 } else { 1517 node = NULL; /* No absolute NODE */ 1518 path = addr; /* Here's the PATH */ 1519 } 1520 1521 /* Snoop for illegal characters in PATH */ 1522 for (k = 0; path[k]; k++) 1523 if (path[k] == ':') 1524 return -1; 1525 1526 /* Check for no repeated dots in PATH */ 1527 for (k = 0; path[k]; k++) 1528 if (path[k] == '.' && path[k + 1] == '.') 1529 return -1; 1530 1531 /* Remove extra (degenerate) dots from beginning or end of PATH */ 1532 if (path[0] == '.') 1533 path++; 1534 if (*path && path[strlen(path) - 1] == '.') 1535 path[strlen(path) - 1] = 0; 1536 1537 /* If PATH has a dot, then we're not talking about a hook */ 1538 if (*path) { 1539 for (hook = path, k = 0; path[k]; k++) 1540 if (path[k] == '.') { 1541 hook = NULL; 1542 break; 1543 } 1544 } else 1545 path = hook = NULL; 1546 1547 /* Done */ 1548 if (nodep) 1549 *nodep = node; 1550 if (pathp) 1551 *pathp = path; 1552 if (hookp) 1553 *hookp = hook; 1554 return (0); 1555 } 1556 1557 /* 1558 * Given a path, which may be absolute or relative, and a starting node, 1559 * return the destination node. 1560 */ 1561 int 1562 ng_path2noderef(node_p here, const char *address, 1563 node_p *destp, hook_p *lasthook) 1564 { 1565 char fullpath[NG_PATHSIZ]; 1566 char *nodename, *path, pbuf[2]; 1567 node_p node, oldnode; 1568 char *cp; 1569 hook_p hook = NULL; 1570 1571 /* Initialize */ 1572 if (destp == NULL) { 1573 TRAP_ERROR(); 1574 return EINVAL; 1575 } 1576 *destp = NULL; 1577 1578 /* Make a writable copy of address for ng_path_parse() */ 1579 strncpy(fullpath, address, sizeof(fullpath) - 1); 1580 fullpath[sizeof(fullpath) - 1] = '\0'; 1581 1582 /* Parse out node and sequence of hooks */ 1583 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) { 1584 TRAP_ERROR(); 1585 return EINVAL; 1586 } 1587 if (path == NULL) { 1588 pbuf[0] = '.'; /* Needs to be writable */ 1589 pbuf[1] = '\0'; 1590 path = pbuf; 1591 } 1592 1593 /* 1594 * For an absolute address, jump to the starting node. 1595 * Note that this holds a reference on the node for us. 1596 * Don't forget to drop the reference if we don't need it. 1597 */ 1598 if (nodename) { 1599 node = ng_name2noderef(here, nodename); 1600 if (node == NULL) { 1601 TRAP_ERROR(); 1602 return (ENOENT); 1603 } 1604 } else { 1605 if (here == NULL) { 1606 TRAP_ERROR(); 1607 return (EINVAL); 1608 } 1609 node = here; 1610 NG_NODE_REF(node); 1611 } 1612 1613 /* 1614 * Now follow the sequence of hooks 1615 * XXX 1616 * We actually cannot guarantee that the sequence 1617 * is not being demolished as we crawl along it 1618 * without extra-ordinary locking etc. 1619 * So this is a bit dodgy to say the least. 1620 * We can probably hold up some things by holding 1621 * the nodelist mutex for the time of this 1622 * crawl if we wanted.. At least that way we wouldn't have to 1623 * worry about the nodes dissappearing, but the hooks would still 1624 * be a problem. 1625 */ 1626 for (cp = path; node != NULL && *cp != '\0'; ) { 1627 char *segment; 1628 1629 /* 1630 * Break out the next path segment. Replace the dot we just 1631 * found with a NUL; "cp" points to the next segment (or the 1632 * NUL at the end). 1633 */ 1634 for (segment = cp; *cp != '\0'; cp++) { 1635 if (*cp == '.') { 1636 *cp++ = '\0'; 1637 break; 1638 } 1639 } 1640 1641 /* Empty segment */ 1642 if (*segment == '\0') 1643 continue; 1644 1645 /* We have a segment, so look for a hook by that name */ 1646 hook = ng_findhook(node, segment); 1647 1648 /* Can't get there from here... */ 1649 if (hook == NULL 1650 || NG_HOOK_PEER(hook) == NULL 1651 || NG_HOOK_NOT_VALID(hook) 1652 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) { 1653 TRAP_ERROR(); 1654 NG_NODE_UNREF(node); 1655 #if 0 1656 printf("hooknotvalid %s %s %d %d %d %d ", 1657 path, 1658 segment, 1659 hook == NULL, 1660 NG_HOOK_PEER(hook) == NULL, 1661 NG_HOOK_NOT_VALID(hook), 1662 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))); 1663 #endif 1664 return (ENOENT); 1665 } 1666 1667 /* 1668 * Hop on over to the next node 1669 * XXX 1670 * Big race conditions here as hooks and nodes go away 1671 * *** Idea.. store an ng_ID_t in each hook and use that 1672 * instead of the direct hook in this crawl? 1673 */ 1674 oldnode = node; 1675 if ((node = NG_PEER_NODE(hook))) 1676 NG_NODE_REF(node); /* XXX RACE */ 1677 NG_NODE_UNREF(oldnode); /* XXX another race */ 1678 if (NG_NODE_NOT_VALID(node)) { 1679 NG_NODE_UNREF(node); /* XXX more races */ 1680 node = NULL; 1681 } 1682 } 1683 1684 /* If node somehow missing, fail here (probably this is not needed) */ 1685 if (node == NULL) { 1686 TRAP_ERROR(); 1687 return (ENXIO); 1688 } 1689 1690 /* Done */ 1691 *destp = node; 1692 if (lasthook != NULL) 1693 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL); 1694 return (0); 1695 } 1696 1697 /***************************************************************\ 1698 * Input queue handling. 1699 * All activities are submitted to the node via the input queue 1700 * which implements a multiple-reader/single-writer gate. 1701 * Items which cannot be handled immeditly are queued. 1702 * 1703 * read-write queue locking inline functions * 1704 \***************************************************************/ 1705 1706 static __inline item_p ng_dequeue(struct ng_queue * ngq); 1707 static __inline item_p ng_acquire_read(struct ng_queue * ngq, 1708 item_p item); 1709 static __inline item_p ng_acquire_write(struct ng_queue * ngq, 1710 item_p item); 1711 static __inline void ng_leave_read(struct ng_queue * ngq); 1712 static __inline void ng_leave_write(struct ng_queue * ngq); 1713 static __inline void ng_queue_rw(struct ng_queue * ngq, 1714 item_p item, int rw); 1715 1716 /* 1717 * Definition of the bits fields in the ng_queue flag word. 1718 * Defined here rather than in netgraph.h because no-one should fiddle 1719 * with them. 1720 * 1721 * The ordering here may be important! don't shuffle these. 1722 */ 1723 /*- 1724 Safety Barrier--------+ (adjustable to suit taste) (not used yet) 1725 | 1726 V 1727 +-------+-------+-------+-------+-------+-------+-------+-------+ 1728 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1729 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |R|A|W| 1730 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |P|W|P| 1731 +-------+-------+-------+-------+-------+-------+-------+-------+ 1732 \___________________________ ____________________________/ | | | 1733 V | | | 1734 [active reader count] | | | 1735 | | | 1736 Read Pending ------------------------------------+ | | 1737 | | 1738 Active Writer -------------------------------------+ | 1739 | 1740 Write Pending ---------------------------------------+ 1741 1742 1743 */ 1744 #define WRITE_PENDING 0x00000001 1745 #define WRITER_ACTIVE 0x00000002 1746 #define READ_PENDING 0x00000004 1747 #define READER_INCREMENT 0x00000008 1748 #define READER_MASK 0xfffffff0 /* Not valid if WRITER_ACTIVE is set */ 1749 #define SAFETY_BARRIER 0x00100000 /* 64K items queued should be enough */ 1750 1751 /* Defines of more elaborate states on the queue */ 1752 /* Mask of bits a read cares about */ 1753 #define NGQ_RMASK (WRITE_PENDING|WRITER_ACTIVE|READ_PENDING) 1754 1755 /* Mask of bits a write cares about */ 1756 #define NGQ_WMASK (NGQ_RMASK|READER_MASK) 1757 1758 /* tests to decide if we could get a read or write off the queue */ 1759 #define CAN_GET_READ(flag) ((flag & NGQ_RMASK) == READ_PENDING) 1760 #define CAN_GET_WRITE(flag) ((flag & NGQ_WMASK) == WRITE_PENDING) 1761 1762 /* Is there a chance of getting ANY work off the queue? */ 1763 #define CAN_GET_WORK(flag) (CAN_GET_READ(flag) || CAN_GET_WRITE(flag)) 1764 1765 /* 1766 * Taking into account the current state of the queue and node, possibly take 1767 * the next entry off the queue and return it. Return NULL if there was 1768 * nothing we could return, either because there really was nothing there, or 1769 * because the node was in a state where it cannot yet process the next item 1770 * on the queue. 1771 * 1772 * This MUST MUST MUST be called with the mutex held. 1773 */ 1774 static __inline item_p 1775 ng_dequeue(struct ng_queue *ngq) 1776 { 1777 item_p item; 1778 u_int add_arg; 1779 1780 mtx_assert(&ngq->q_mtx, MA_OWNED); 1781 1782 if (CAN_GET_READ(ngq->q_flags)) { 1783 /* 1784 * Head of queue is a reader and we have no write active. 1785 * We don't care how many readers are already active. 1786 * Adjust the flags for the item we are about to dequeue. 1787 * Add the correct increment for the reader count as well. 1788 */ 1789 add_arg = (READER_INCREMENT - READ_PENDING); 1790 } else if (CAN_GET_WRITE(ngq->q_flags)) { 1791 /* 1792 * There is a pending write, no readers and no active writer. 1793 * This means we can go ahead with the pending writer. Note 1794 * the fact that we now have a writer, ready for when we take 1795 * it off the queue. 1796 * 1797 * We don't need to worry about a possible collision with the 1798 * fasttrack reader. 1799 * 1800 * The fasttrack thread may take a long time to discover that we 1801 * are running so we would have an inconsistent state in the 1802 * flags for a while. Since we ignore the reader count 1803 * entirely when the WRITER_ACTIVE flag is set, this should 1804 * not matter (in fact it is defined that way). If it tests 1805 * the flag before this operation, the WRITE_PENDING flag 1806 * will make it fail, and if it tests it later, the 1807 * WRITER_ACTIVE flag will do the same. If it is SO slow that 1808 * we have actually completed the operation, and neither flag 1809 * is set (nor the READ_PENDING) by the time that it tests 1810 * the flags, then it is actually ok for it to continue. If 1811 * it completes and we've finished and the read pending is 1812 * set it still fails. 1813 * 1814 * So we can just ignore it, as long as we can ensure that the 1815 * transition from WRITE_PENDING state to the WRITER_ACTIVE 1816 * state is atomic. 1817 * 1818 * After failing, first it will be held back by the mutex, then 1819 * when it can proceed, it will queue its request, then it 1820 * would arrive at this function. Usually it will have to 1821 * leave empty handed because the ACTIVE WRITER bit will be 1822 * set. 1823 * 1824 * Adjust the flags for the item we are about to dequeue 1825 * and for the new active writer. 1826 */ 1827 add_arg = (WRITER_ACTIVE - WRITE_PENDING); 1828 /* 1829 * We want to write "active writer, no readers " Now go make 1830 * it true. In fact there may be a number in the readers 1831 * count but we know it is not true and will be fixed soon. 1832 * We will fix the flags for the next pending entry in a 1833 * moment. 1834 */ 1835 } else { 1836 /* 1837 * We can't dequeue anything.. return and say so. Probably we 1838 * have a write pending and the readers count is non zero. If 1839 * we got here because a reader hit us just at the wrong 1840 * moment with the fasttrack code, and put us in a strange 1841 * state, then it will be through in just a moment, (as soon 1842 * as we release the mutex) and keep things moving. 1843 * Make sure we remove ourselves from the work queue. 1844 */ 1845 ng_worklist_remove(ngq->q_node); 1846 return (0); 1847 } 1848 1849 /* 1850 * Now we dequeue the request (whatever it may be) and correct the 1851 * pending flags and the next and last pointers. 1852 */ 1853 item = ngq->queue; 1854 ngq->queue = item->el_next; 1855 if (ngq->last == &(item->el_next)) { 1856 /* 1857 * that was the last entry in the queue so set the 'last 1858 * pointer up correctly and make sure the pending flags are 1859 * clear. 1860 */ 1861 ngq->last = &(ngq->queue); 1862 /* 1863 * Whatever flag was set will be cleared and 1864 * the new acive field will be set by the add as well, 1865 * so we don't need to change add_arg. 1866 * But we know we don't need to be on the work list. 1867 */ 1868 atomic_add_long(&ngq->q_flags, add_arg); 1869 ng_worklist_remove(ngq->q_node); 1870 } else { 1871 /* 1872 * Since there is something on the queue, note what it is 1873 * in the flags word. 1874 */ 1875 if ((ngq->queue->el_flags & NGQF_RW) == NGQF_READER) { 1876 add_arg += READ_PENDING; 1877 } else { 1878 add_arg += WRITE_PENDING; 1879 } 1880 atomic_add_long(&ngq->q_flags, add_arg); 1881 /* 1882 * If we see more doable work, make sure we are 1883 * on the work queue. 1884 */ 1885 if (CAN_GET_WORK(ngq->q_flags)) { 1886 ng_setisr(ngq->q_node); 1887 } 1888 } 1889 /* 1890 * We have successfully cleared the old pending flag, set the new one 1891 * if it is needed, and incremented the appropriate active field. 1892 * (all in one atomic addition.. ) 1893 */ 1894 return (item); 1895 } 1896 1897 /* 1898 * Queue a packet to be picked up by someone else. 1899 * We really don't care who, but we can't or don't want to hang around 1900 * to process it ourselves. We are probably an interrupt routine.. 1901 * 1 = writer, 0 = reader 1902 */ 1903 #define NGQRW_R 0 1904 #define NGQRW_W 1 1905 static __inline void 1906 ng_queue_rw(struct ng_queue * ngq, item_p item, int rw) 1907 { 1908 mtx_assert(&ngq->q_mtx, MA_OWNED); 1909 1910 item->el_next = NULL; /* maybe not needed */ 1911 *ngq->last = item; 1912 /* 1913 * If it was the first item in the queue then we need to 1914 * set the last pointer and the type flags. 1915 */ 1916 if (ngq->last == &(ngq->queue)) { 1917 /* 1918 * When called with constants for rw, the optimiser will 1919 * remove the unneeded branch below. 1920 */ 1921 if (rw == NGQRW_W) { 1922 atomic_add_long(&ngq->q_flags, WRITE_PENDING); 1923 } else { 1924 atomic_add_long(&ngq->q_flags, READ_PENDING); 1925 } 1926 } 1927 ngq->last = &(item->el_next); 1928 } 1929 1930 1931 /* 1932 * This function 'cheats' in that it first tries to 'grab' the use of the 1933 * node, without going through the mutex. We can do this becasue of the 1934 * semantics of the lock. The semantics include a clause that says that the 1935 * value of the readers count is invalid if the WRITER_ACTIVE flag is set. It 1936 * also says that the WRITER_ACTIVE flag cannot be set if the readers count 1937 * is not zero. Note that this talks about what is valid to SET the 1938 * WRITER_ACTIVE flag, because from the moment it is set, the value if the 1939 * reader count is immaterial, and not valid. The two 'pending' flags have a 1940 * similar effect, in that If they are orthogonal to the two active fields in 1941 * how they are set, but if either is set, the attempted 'grab' need to be 1942 * backed out because there is earlier work, and we maintain ordering in the 1943 * queue. The result of this is that the reader request can try obtain use of 1944 * the node with only a single atomic addition, and without any of the mutex 1945 * overhead. If this fails the operation degenerates to the same as for other 1946 * cases. 1947 * 1948 */ 1949 static __inline item_p 1950 ng_acquire_read(struct ng_queue *ngq, item_p item) 1951 { 1952 1953 /* ######### Hack alert ######### */ 1954 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 1955 if ((ngq->q_flags & NGQ_RMASK) == 0) { 1956 /* Successfully grabbed node */ 1957 return (item); 1958 } 1959 /* undo the damage if we didn't succeed */ 1960 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 1961 1962 /* ######### End Hack alert ######### */ 1963 mtx_lock_spin((&ngq->q_mtx)); 1964 /* 1965 * Try again. Another processor (or interrupt for that matter) may 1966 * have removed the last queued item that was stopping us from 1967 * running, between the previous test, and the moment that we took 1968 * the mutex. (Or maybe a writer completed.) 1969 */ 1970 if ((ngq->q_flags & NGQ_RMASK) == 0) { 1971 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 1972 mtx_unlock_spin((&ngq->q_mtx)); 1973 return (item); 1974 } 1975 1976 /* 1977 * and queue the request for later. 1978 */ 1979 item->el_flags |= NGQF_READER; 1980 ng_queue_rw(ngq, item, NGQRW_R); 1981 1982 /* 1983 * Ok, so that's the item successfully queued for later. So now we 1984 * see if we can dequeue something to run instead. 1985 */ 1986 item = ng_dequeue(ngq); 1987 mtx_unlock_spin(&(ngq->q_mtx)); 1988 return (item); 1989 } 1990 1991 static __inline item_p 1992 ng_acquire_write(struct ng_queue *ngq, item_p item) 1993 { 1994 restart: 1995 mtx_lock_spin(&(ngq->q_mtx)); 1996 /* 1997 * If there are no readers, no writer, and no pending packets, then 1998 * we can just go ahead. In all other situations we need to queue the 1999 * request 2000 */ 2001 if ((ngq->q_flags & NGQ_WMASK) == 0) { 2002 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE); 2003 mtx_unlock_spin((&ngq->q_mtx)); 2004 if (ngq->q_flags & READER_MASK) { 2005 /* Collision with fast-track reader */ 2006 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2007 goto restart; 2008 } 2009 return (item); 2010 } 2011 2012 /* 2013 * and queue the request for later. 2014 */ 2015 item->el_flags &= ~NGQF_RW; 2016 ng_queue_rw(ngq, item, NGQRW_W); 2017 2018 /* 2019 * Ok, so that's the item successfully queued for later. So now we 2020 * see if we can dequeue something to run instead. 2021 */ 2022 item = ng_dequeue(ngq); 2023 mtx_unlock_spin(&(ngq->q_mtx)); 2024 return (item); 2025 } 2026 2027 static __inline void 2028 ng_leave_read(struct ng_queue *ngq) 2029 { 2030 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 2031 } 2032 2033 static __inline void 2034 ng_leave_write(struct ng_queue *ngq) 2035 { 2036 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2037 } 2038 2039 static void 2040 ng_flush_input_queue(struct ng_queue * ngq) 2041 { 2042 item_p item; 2043 u_int add_arg; 2044 mtx_lock_spin(&ngq->q_mtx); 2045 for (;;) { 2046 /* Now take a look at what's on the queue */ 2047 if (ngq->q_flags & READ_PENDING) { 2048 add_arg = -READ_PENDING; 2049 } else if (ngq->q_flags & WRITE_PENDING) { 2050 add_arg = -WRITE_PENDING; 2051 } else { 2052 break; 2053 } 2054 2055 item = ngq->queue; 2056 ngq->queue = item->el_next; 2057 if (ngq->last == &(item->el_next)) { 2058 ngq->last = &(ngq->queue); 2059 } else { 2060 if ((ngq->queue->el_flags & NGQF_RW) == NGQF_READER) { 2061 add_arg += READ_PENDING; 2062 } else { 2063 add_arg += WRITE_PENDING; 2064 } 2065 } 2066 atomic_add_long(&ngq->q_flags, add_arg); 2067 2068 mtx_unlock_spin(&ngq->q_mtx); 2069 NG_FREE_ITEM(item); 2070 mtx_lock_spin(&ngq->q_mtx); 2071 } 2072 /* 2073 * Take us off the work queue if we are there. 2074 * We definatly have no work to be done. 2075 */ 2076 ng_worklist_remove(ngq->q_node); 2077 mtx_unlock_spin(&ngq->q_mtx); 2078 } 2079 2080 /*********************************************************************** 2081 * Externally visible method for sending or queueing messages or data. 2082 ***********************************************************************/ 2083 2084 /* 2085 * The module code should have filled out the item correctly by this stage: 2086 * Common: 2087 * reference to destination node. 2088 * Reference to destination rcv hook if relevant. 2089 * Data: 2090 * pointer to mbuf 2091 * Control_Message: 2092 * pointer to msg. 2093 * ID of original sender node. (return address) 2094 * Function: 2095 * Function pointer 2096 * void * argument 2097 * integer argument 2098 * 2099 * The nodes have several routines and macros to help with this task: 2100 */ 2101 2102 int 2103 ng_snd_item(item_p item, int queue) 2104 { 2105 hook_p hook = NGI_HOOK(item); 2106 node_p node = NGI_NODE(item); 2107 int rw; 2108 int error = 0, ierror; 2109 item_p oitem; 2110 struct ng_queue * ngq = &node->nd_input_queue; 2111 2112 #ifdef NETGRAPH_DEBUG 2113 _ngi_check(item, __FILE__, __LINE__); 2114 #endif 2115 2116 if (item == NULL) { 2117 TRAP_ERROR(); 2118 return (EINVAL); /* failed to get queue element */ 2119 } 2120 if (node == NULL) { 2121 NG_FREE_ITEM(item); 2122 TRAP_ERROR(); 2123 return (EINVAL); /* No address */ 2124 } 2125 switch(item->el_flags & NGQF_TYPE) { 2126 case NGQF_DATA: 2127 /* 2128 * DATA MESSAGE 2129 * Delivered to a node via a non-optional hook. 2130 * Both should be present in the item even though 2131 * the node is derivable from the hook. 2132 * References are held on both by the item. 2133 */ 2134 2135 /* Protect nodes from sending NULL pointers 2136 * to each other 2137 */ 2138 if (NGI_M(item) == NULL) 2139 return (EINVAL); 2140 2141 CHECK_DATA_MBUF(NGI_M(item)); 2142 if (hook == NULL) { 2143 NG_FREE_ITEM(item); 2144 TRAP_ERROR(); 2145 return(EINVAL); 2146 } 2147 if ((NG_HOOK_NOT_VALID(hook)) 2148 || (NG_NODE_NOT_VALID(NG_HOOK_NODE(hook)))) { 2149 NG_FREE_ITEM(item); 2150 return (ENOTCONN); 2151 } 2152 if ((hook->hk_flags & HK_QUEUE)) { 2153 queue = 1; 2154 } 2155 /* By default data is a reader in the locking scheme */ 2156 item->el_flags |= NGQF_READER; 2157 rw = NGQRW_R; 2158 break; 2159 case NGQF_MESG: 2160 /* 2161 * CONTROL MESSAGE 2162 * Delivered to a node. 2163 * Hook is optional. 2164 * References are held by the item on the node and 2165 * the hook if it is present. 2166 */ 2167 if (hook && (hook->hk_flags & HK_QUEUE)) { 2168 queue = 1; 2169 } 2170 /* Data messages count as writers unles explicitly exempted */ 2171 if (NGI_MSG(item)->header.cmd & NGM_READONLY) { 2172 item->el_flags |= NGQF_READER; 2173 rw = NGQRW_R; 2174 } else { 2175 item->el_flags &= ~NGQF_RW; 2176 rw = NGQRW_W; 2177 } 2178 break; 2179 case NGQF_FN: 2180 item->el_flags &= ~NGQF_RW; 2181 rw = NGQRW_W; 2182 break; 2183 default: 2184 NG_FREE_ITEM(item); 2185 TRAP_ERROR(); 2186 return (EINVAL); 2187 } 2188 /* 2189 * If the node specifies single threading, force writer semantics 2190 * Similarly the node may say one hook always produces writers. 2191 * These are over-rides. 2192 */ 2193 if ((node->nd_flags & NGF_FORCE_WRITER) 2194 || (hook && (hook->hk_flags & HK_FORCE_WRITER))) { 2195 rw = NGQRW_W; 2196 item->el_flags &= ~NGQF_READER; 2197 } 2198 if (queue) { 2199 /* Put it on the queue for that node*/ 2200 #ifdef NETGRAPH_DEBUG 2201 _ngi_check(item, __FILE__, __LINE__); 2202 #endif 2203 mtx_lock_spin(&(ngq->q_mtx)); 2204 ng_queue_rw(ngq, item, rw); 2205 /* 2206 * If there are active elements then we can rely on 2207 * them. if not we should not rely on another packet 2208 * coming here by another path, 2209 * so it is best to put us in the netisr list. 2210 * We can take the worklist lock with the node locked 2211 * BUT NOT THE REVERSE! 2212 */ 2213 if (CAN_GET_WORK(ngq->q_flags)) { 2214 ng_setisr(node); 2215 } 2216 mtx_unlock_spin(&(ngq->q_mtx)); 2217 return (0); 2218 } 2219 /* 2220 * Take a queue item and a node and see if we can apply the item to 2221 * the node. We may end up getting a different item to apply instead. 2222 * Will allow for a piggyback reply only in the case where 2223 * there is no queueing. 2224 */ 2225 2226 oitem = item; 2227 /* 2228 * We already decided how we will be queueud or treated. 2229 * Try get the appropriate operating permission. 2230 */ 2231 if (rw == NGQRW_R) { 2232 item = ng_acquire_read(ngq, item); 2233 } else { 2234 item = ng_acquire_write(ngq, item); 2235 } 2236 2237 /* 2238 * May have come back with a different item. 2239 * or maybe none at all. The one we started with will 2240 * have been queued in thises cases. 2241 */ 2242 if (item == NULL) { 2243 return (0); 2244 } 2245 2246 #ifdef NETGRAPH_DEBUG 2247 _ngi_check(item, __FILE__, __LINE__); 2248 #endif 2249 /* 2250 * Take over the reference frm the item. 2251 * Hold it until the called function returns. 2252 */ 2253 NGI_GET_NODE(item, node); /* zaps stored node */ 2254 2255 ierror = ng_apply_item(node, item); /* drops r/w lock when done */ 2256 2257 /* only return an error if it was our initial item.. (compat hack) */ 2258 if (oitem == item) { 2259 error = ierror; 2260 } 2261 2262 /* 2263 * If the node goes away when we remove the reference, 2264 * whatever we just did caused it.. whatever we do, DO NOT 2265 * access the node again! 2266 */ 2267 if (NG_NODE_UNREF(node) == 0) { 2268 return (error); 2269 } 2270 2271 /* 2272 * Now we've handled the packet we brought, (or a friend of it) let's 2273 * look for any other packets that may have been queued up. We hold 2274 * no locks, so if someone puts something in the queue after 2275 * we check that it is empty, it is their problem 2276 * to ensure it is processed. If we have the netisr thread cme in here 2277 * while we still say we have stuff to do, we may get a boost 2278 * in SMP systems. :-) 2279 */ 2280 for (;;) { 2281 /* 2282 * dequeue acquires and adjusts the input_queue as it dequeues 2283 * packets. It acquires the rw lock as needed. 2284 */ 2285 mtx_lock_spin(&ngq->q_mtx); 2286 item = ng_dequeue(ngq); /* fixes worklist too*/ 2287 if (!item) { 2288 mtx_unlock_spin(&ngq->q_mtx); 2289 return (error); 2290 } 2291 mtx_unlock_spin(&ngq->q_mtx); 2292 2293 /* 2294 * Take over the reference frm the item. 2295 * Hold it until the called function returns. 2296 */ 2297 2298 NGI_GET_NODE(item, node); /* zaps stored node */ 2299 2300 /* 2301 * We have the appropriate lock, so run the item. 2302 * When finished it will drop the lock accordingly 2303 */ 2304 ierror = ng_apply_item(node, item); 2305 2306 /* 2307 * only return an error if it was our initial 2308 * item.. (compat hack) 2309 */ 2310 if (oitem == item) { 2311 error = ierror; 2312 } 2313 2314 /* 2315 * If the node goes away when we remove the reference, 2316 * whatever we just did caused it.. whatever we do, DO NOT 2317 * access the node again! 2318 */ 2319 if (NG_NODE_UNREF(node) == 0) { 2320 break; 2321 } 2322 } 2323 return (error); 2324 } 2325 2326 /* 2327 * We have an item that was possibly queued somewhere. 2328 * It should contain all the information needed 2329 * to run it on the appropriate node/hook. 2330 */ 2331 static int 2332 ng_apply_item(node_p node, item_p item) 2333 { 2334 hook_p hook; 2335 int was_reader = ((item->el_flags & NGQF_RW)); 2336 int error = 0; 2337 ng_rcvdata_t *rcvdata; 2338 ng_rcvmsg_t *rcvmsg; 2339 2340 NGI_GET_HOOK(item, hook); /* clears stored hook */ 2341 #ifdef NETGRAPH_DEBUG 2342 _ngi_check(item, __FILE__, __LINE__); 2343 #endif 2344 switch (item->el_flags & NGQF_TYPE) { 2345 case NGQF_DATA: 2346 /* 2347 * Check things are still ok as when we were queued. 2348 */ 2349 if ((hook == NULL) 2350 || NG_HOOK_NOT_VALID(hook) 2351 || NG_NODE_NOT_VALID(node) ) { 2352 error = EIO; 2353 NG_FREE_ITEM(item); 2354 break; 2355 } 2356 /* 2357 * If no receive method, just silently drop it. 2358 * Give preference to the hook over-ride method 2359 */ 2360 if ((!(rcvdata = hook->hk_rcvdata)) 2361 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) { 2362 error = 0; 2363 NG_FREE_ITEM(item); 2364 break; 2365 } 2366 error = (*rcvdata)(hook, item); 2367 break; 2368 case NGQF_MESG: 2369 if (hook) { 2370 if (NG_HOOK_NOT_VALID(hook)) { 2371 /* 2372 * The hook has been zapped then we can't 2373 * use it. Immediatly drop its reference. 2374 * The message may not need it. 2375 */ 2376 NG_HOOK_UNREF(hook); 2377 hook = NULL; 2378 } 2379 } 2380 /* 2381 * Similarly, if the node is a zombie there is 2382 * nothing we can do with it, drop everything. 2383 */ 2384 if (NG_NODE_NOT_VALID(node)) { 2385 TRAP_ERROR(); 2386 error = EINVAL; 2387 NG_FREE_ITEM(item); 2388 } else { 2389 /* 2390 * Call the appropriate message handler for the object. 2391 * It is up to the message handler to free the message. 2392 * If it's a generic message, handle it generically, 2393 * otherwise call the type's message handler 2394 * (if it exists) 2395 * XXX (race). Remember that a queued message may 2396 * reference a node or hook that has just been 2397 * invalidated. It will exist as the queue code 2398 * is holding a reference, but.. 2399 */ 2400 2401 struct ng_mesg *msg = NGI_MSG(item); 2402 2403 /* 2404 * check if the generic handler owns it. 2405 */ 2406 if ((msg->header.typecookie == NGM_GENERIC_COOKIE) 2407 && ((msg->header.flags & NGF_RESP) == 0)) { 2408 error = ng_generic_msg(node, item, hook); 2409 break; 2410 } 2411 /* 2412 * Now see if there is a handler (hook or node specific) 2413 * in the target node. If none, silently discard. 2414 */ 2415 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) 2416 && (!(rcvmsg = node->nd_type->rcvmsg))) { 2417 TRAP_ERROR(); 2418 error = 0; 2419 NG_FREE_ITEM(item); 2420 break; 2421 } 2422 error = (*rcvmsg)(node, item, hook); 2423 } 2424 break; 2425 case NGQF_FN: 2426 /* 2427 * We have to implicitly trust the hook, 2428 * as some of these are used for system purposes 2429 * where the hook is invalid. In the case of 2430 * the shutdown message we allow it to hit 2431 * even if the node is invalid. 2432 */ 2433 if ((NG_NODE_NOT_VALID(node)) 2434 && (NGI_FN(item) != &ng_rmnode)) { 2435 TRAP_ERROR(); 2436 error = EINVAL; 2437 break; 2438 } 2439 (*NGI_FN(item))(node, hook, NGI_ARG1(item), NGI_ARG2(item)); 2440 NG_FREE_ITEM(item); 2441 break; 2442 2443 } 2444 /* 2445 * We held references on some of the resources 2446 * that we took from the item. Now that we have 2447 * finished doing everything, drop those references. 2448 */ 2449 if (hook) { 2450 NG_HOOK_UNREF(hook); 2451 } 2452 2453 if (was_reader) { 2454 ng_leave_read(&node->nd_input_queue); 2455 } else { 2456 ng_leave_write(&node->nd_input_queue); 2457 } 2458 return (error); 2459 } 2460 2461 /*********************************************************************** 2462 * Implement the 'generic' control messages 2463 ***********************************************************************/ 2464 static int 2465 ng_generic_msg(node_p here, item_p item, hook_p lasthook) 2466 { 2467 int error = 0; 2468 struct ng_mesg *msg; 2469 struct ng_mesg *resp = NULL; 2470 2471 NGI_GET_MSG(item, msg); 2472 if (msg->header.typecookie != NGM_GENERIC_COOKIE) { 2473 TRAP_ERROR(); 2474 error = EINVAL; 2475 goto out; 2476 } 2477 switch (msg->header.cmd) { 2478 case NGM_SHUTDOWN: 2479 ng_rmnode(here, NULL, NULL, 0); 2480 break; 2481 case NGM_MKPEER: 2482 { 2483 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data; 2484 2485 if (msg->header.arglen != sizeof(*mkp)) { 2486 TRAP_ERROR(); 2487 error = EINVAL; 2488 break; 2489 } 2490 mkp->type[sizeof(mkp->type) - 1] = '\0'; 2491 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0'; 2492 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0'; 2493 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type); 2494 break; 2495 } 2496 case NGM_CONNECT: 2497 { 2498 struct ngm_connect *const con = 2499 (struct ngm_connect *) msg->data; 2500 node_p node2; 2501 2502 if (msg->header.arglen != sizeof(*con)) { 2503 TRAP_ERROR(); 2504 error = EINVAL; 2505 break; 2506 } 2507 con->path[sizeof(con->path) - 1] = '\0'; 2508 con->ourhook[sizeof(con->ourhook) - 1] = '\0'; 2509 con->peerhook[sizeof(con->peerhook) - 1] = '\0'; 2510 /* Don't forget we get a reference.. */ 2511 error = ng_path2noderef(here, con->path, &node2, NULL); 2512 if (error) 2513 break; 2514 error = ng_con_nodes(here, con->ourhook, node2, con->peerhook); 2515 NG_NODE_UNREF(node2); 2516 break; 2517 } 2518 case NGM_NAME: 2519 { 2520 struct ngm_name *const nam = (struct ngm_name *) msg->data; 2521 2522 if (msg->header.arglen != sizeof(*nam)) { 2523 TRAP_ERROR(); 2524 error = EINVAL; 2525 break; 2526 } 2527 nam->name[sizeof(nam->name) - 1] = '\0'; 2528 error = ng_name_node(here, nam->name); 2529 break; 2530 } 2531 case NGM_RMHOOK: 2532 { 2533 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data; 2534 hook_p hook; 2535 2536 if (msg->header.arglen != sizeof(*rmh)) { 2537 TRAP_ERROR(); 2538 error = EINVAL; 2539 break; 2540 } 2541 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0'; 2542 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL) 2543 ng_destroy_hook(hook); 2544 break; 2545 } 2546 case NGM_NODEINFO: 2547 { 2548 struct nodeinfo *ni; 2549 2550 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT); 2551 if (resp == NULL) { 2552 error = ENOMEM; 2553 break; 2554 } 2555 2556 /* Fill in node info */ 2557 ni = (struct nodeinfo *) resp->data; 2558 if (NG_NODE_HAS_NAME(here)) 2559 strcpy(ni->name, NG_NODE_NAME(here)); 2560 strcpy(ni->type, here->nd_type->name); 2561 ni->id = ng_node2ID(here); 2562 ni->hooks = here->nd_numhooks; 2563 break; 2564 } 2565 case NGM_LISTHOOKS: 2566 { 2567 const int nhooks = here->nd_numhooks; 2568 struct hooklist *hl; 2569 struct nodeinfo *ni; 2570 hook_p hook; 2571 2572 /* Get response struct */ 2573 NG_MKRESPONSE(resp, msg, sizeof(*hl) 2574 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT); 2575 if (resp == NULL) { 2576 error = ENOMEM; 2577 break; 2578 } 2579 hl = (struct hooklist *) resp->data; 2580 ni = &hl->nodeinfo; 2581 2582 /* Fill in node info */ 2583 if (NG_NODE_HAS_NAME(here)) 2584 strcpy(ni->name, NG_NODE_NAME(here)); 2585 strcpy(ni->type, here->nd_type->name); 2586 ni->id = ng_node2ID(here); 2587 2588 /* Cycle through the linked list of hooks */ 2589 ni->hooks = 0; 2590 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) { 2591 struct linkinfo *const link = &hl->link[ni->hooks]; 2592 2593 if (ni->hooks >= nhooks) { 2594 log(LOG_ERR, "%s: number of %s changed\n", 2595 __func__, "hooks"); 2596 break; 2597 } 2598 if (NG_HOOK_NOT_VALID(hook)) 2599 continue; 2600 strcpy(link->ourhook, NG_HOOK_NAME(hook)); 2601 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook)); 2602 if (NG_PEER_NODE_NAME(hook)[0] != '\0') 2603 strcpy(link->nodeinfo.name, 2604 NG_PEER_NODE_NAME(hook)); 2605 strcpy(link->nodeinfo.type, 2606 NG_PEER_NODE(hook)->nd_type->name); 2607 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook)); 2608 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks; 2609 ni->hooks++; 2610 } 2611 break; 2612 } 2613 2614 case NGM_LISTNAMES: 2615 case NGM_LISTNODES: 2616 { 2617 const int unnamed = (msg->header.cmd == NGM_LISTNODES); 2618 struct namelist *nl; 2619 node_p node; 2620 int num = 0; 2621 2622 mtx_lock(&ng_nodelist_mtx); 2623 /* Count number of nodes */ 2624 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2625 if (NG_NODE_IS_VALID(node) 2626 && (unnamed || NG_NODE_HAS_NAME(node))) { 2627 num++; 2628 } 2629 } 2630 mtx_unlock(&ng_nodelist_mtx); 2631 2632 /* Get response struct */ 2633 NG_MKRESPONSE(resp, msg, sizeof(*nl) 2634 + (num * sizeof(struct nodeinfo)), M_NOWAIT); 2635 if (resp == NULL) { 2636 error = ENOMEM; 2637 break; 2638 } 2639 nl = (struct namelist *) resp->data; 2640 2641 /* Cycle through the linked list of nodes */ 2642 nl->numnames = 0; 2643 mtx_lock(&ng_nodelist_mtx); 2644 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2645 struct nodeinfo *const np = &nl->nodeinfo[nl->numnames]; 2646 2647 if (nl->numnames >= num) { 2648 log(LOG_ERR, "%s: number of %s changed\n", 2649 __func__, "nodes"); 2650 break; 2651 } 2652 if (NG_NODE_NOT_VALID(node)) 2653 continue; 2654 if (!unnamed && (! NG_NODE_HAS_NAME(node))) 2655 continue; 2656 if (NG_NODE_HAS_NAME(node)) 2657 strcpy(np->name, NG_NODE_NAME(node)); 2658 strcpy(np->type, node->nd_type->name); 2659 np->id = ng_node2ID(node); 2660 np->hooks = node->nd_numhooks; 2661 nl->numnames++; 2662 } 2663 mtx_unlock(&ng_nodelist_mtx); 2664 break; 2665 } 2666 2667 case NGM_LISTTYPES: 2668 { 2669 struct typelist *tl; 2670 struct ng_type *type; 2671 int num = 0; 2672 2673 mtx_lock(&ng_typelist_mtx); 2674 /* Count number of types */ 2675 LIST_FOREACH(type, &ng_typelist, types) { 2676 num++; 2677 } 2678 mtx_unlock(&ng_typelist_mtx); 2679 2680 /* Get response struct */ 2681 NG_MKRESPONSE(resp, msg, sizeof(*tl) 2682 + (num * sizeof(struct typeinfo)), M_NOWAIT); 2683 if (resp == NULL) { 2684 error = ENOMEM; 2685 break; 2686 } 2687 tl = (struct typelist *) resp->data; 2688 2689 /* Cycle through the linked list of types */ 2690 tl->numtypes = 0; 2691 mtx_lock(&ng_typelist_mtx); 2692 LIST_FOREACH(type, &ng_typelist, types) { 2693 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes]; 2694 2695 if (tl->numtypes >= num) { 2696 log(LOG_ERR, "%s: number of %s changed\n", 2697 __func__, "types"); 2698 break; 2699 } 2700 strcpy(tp->type_name, type->name); 2701 tp->numnodes = type->refs - 1; /* don't count list */ 2702 tl->numtypes++; 2703 } 2704 mtx_unlock(&ng_typelist_mtx); 2705 break; 2706 } 2707 2708 case NGM_BINARY2ASCII: 2709 { 2710 int bufSize = 20 * 1024; /* XXX hard coded constant */ 2711 const struct ng_parse_type *argstype; 2712 const struct ng_cmdlist *c; 2713 struct ng_mesg *binary, *ascii; 2714 2715 /* Data area must contain a valid netgraph message */ 2716 binary = (struct ng_mesg *)msg->data; 2717 if (msg->header.arglen < sizeof(struct ng_mesg) 2718 || (msg->header.arglen - sizeof(struct ng_mesg) 2719 < binary->header.arglen)) { 2720 TRAP_ERROR(); 2721 error = EINVAL; 2722 break; 2723 } 2724 2725 /* Get a response message with lots of room */ 2726 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT); 2727 if (resp == NULL) { 2728 error = ENOMEM; 2729 break; 2730 } 2731 ascii = (struct ng_mesg *)resp->data; 2732 2733 /* Copy binary message header to response message payload */ 2734 bcopy(binary, ascii, sizeof(*binary)); 2735 2736 /* Find command by matching typecookie and command number */ 2737 for (c = here->nd_type->cmdlist; 2738 c != NULL && c->name != NULL; c++) { 2739 if (binary->header.typecookie == c->cookie 2740 && binary->header.cmd == c->cmd) 2741 break; 2742 } 2743 if (c == NULL || c->name == NULL) { 2744 for (c = ng_generic_cmds; c->name != NULL; c++) { 2745 if (binary->header.typecookie == c->cookie 2746 && binary->header.cmd == c->cmd) 2747 break; 2748 } 2749 if (c->name == NULL) { 2750 NG_FREE_MSG(resp); 2751 error = ENOSYS; 2752 break; 2753 } 2754 } 2755 2756 /* Convert command name to ASCII */ 2757 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr), 2758 "%s", c->name); 2759 2760 /* Convert command arguments to ASCII */ 2761 argstype = (binary->header.flags & NGF_RESP) ? 2762 c->respType : c->mesgType; 2763 if (argstype == NULL) { 2764 *ascii->data = '\0'; 2765 } else { 2766 if ((error = ng_unparse(argstype, 2767 (u_char *)binary->data, 2768 ascii->data, bufSize)) != 0) { 2769 NG_FREE_MSG(resp); 2770 break; 2771 } 2772 } 2773 2774 /* Return the result as struct ng_mesg plus ASCII string */ 2775 bufSize = strlen(ascii->data) + 1; 2776 ascii->header.arglen = bufSize; 2777 resp->header.arglen = sizeof(*ascii) + bufSize; 2778 break; 2779 } 2780 2781 case NGM_ASCII2BINARY: 2782 { 2783 int bufSize = 2000; /* XXX hard coded constant */ 2784 const struct ng_cmdlist *c; 2785 const struct ng_parse_type *argstype; 2786 struct ng_mesg *ascii, *binary; 2787 int off = 0; 2788 2789 /* Data area must contain at least a struct ng_mesg + '\0' */ 2790 ascii = (struct ng_mesg *)msg->data; 2791 if ((msg->header.arglen < sizeof(*ascii) + 1) 2792 || (ascii->header.arglen < 1) 2793 || (msg->header.arglen 2794 < sizeof(*ascii) + ascii->header.arglen)) { 2795 TRAP_ERROR(); 2796 error = EINVAL; 2797 break; 2798 } 2799 ascii->data[ascii->header.arglen - 1] = '\0'; 2800 2801 /* Get a response message with lots of room */ 2802 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT); 2803 if (resp == NULL) { 2804 error = ENOMEM; 2805 break; 2806 } 2807 binary = (struct ng_mesg *)resp->data; 2808 2809 /* Copy ASCII message header to response message payload */ 2810 bcopy(ascii, binary, sizeof(*ascii)); 2811 2812 /* Find command by matching ASCII command string */ 2813 for (c = here->nd_type->cmdlist; 2814 c != NULL && c->name != NULL; c++) { 2815 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2816 break; 2817 } 2818 if (c == NULL || c->name == NULL) { 2819 for (c = ng_generic_cmds; c->name != NULL; c++) { 2820 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2821 break; 2822 } 2823 if (c->name == NULL) { 2824 NG_FREE_MSG(resp); 2825 error = ENOSYS; 2826 break; 2827 } 2828 } 2829 2830 /* Convert command name to binary */ 2831 binary->header.cmd = c->cmd; 2832 binary->header.typecookie = c->cookie; 2833 2834 /* Convert command arguments to binary */ 2835 argstype = (binary->header.flags & NGF_RESP) ? 2836 c->respType : c->mesgType; 2837 if (argstype == NULL) { 2838 bufSize = 0; 2839 } else { 2840 if ((error = ng_parse(argstype, ascii->data, 2841 &off, (u_char *)binary->data, &bufSize)) != 0) { 2842 NG_FREE_MSG(resp); 2843 break; 2844 } 2845 } 2846 2847 /* Return the result */ 2848 binary->header.arglen = bufSize; 2849 resp->header.arglen = sizeof(*binary) + bufSize; 2850 break; 2851 } 2852 2853 case NGM_TEXT_CONFIG: 2854 case NGM_TEXT_STATUS: 2855 /* 2856 * This one is tricky as it passes the command down to the 2857 * actual node, even though it is a generic type command. 2858 * This means we must assume that the item/msg is already freed 2859 * when control passes back to us. 2860 */ 2861 if (here->nd_type->rcvmsg != NULL) { 2862 NGI_MSG(item) = msg; /* put it back as we found it */ 2863 return((*here->nd_type->rcvmsg)(here, item, lasthook)); 2864 } 2865 /* Fall through if rcvmsg not supported */ 2866 default: 2867 TRAP_ERROR(); 2868 error = EINVAL; 2869 } 2870 /* 2871 * Sometimes a generic message may be statically allocated 2872 * to avoid problems with allocating when in tight memeory situations. 2873 * Don't free it if it is so. 2874 * I break them appart here, because erros may cause a free if the item 2875 * in which case we'd be doing it twice. 2876 * they are kept together above, to simplify freeing. 2877 */ 2878 out: 2879 NG_RESPOND_MSG(error, here, item, resp); 2880 if (msg) 2881 NG_FREE_MSG(msg); 2882 return (error); 2883 } 2884 2885 /************************************************************************ 2886 Module routines 2887 ************************************************************************/ 2888 2889 /* 2890 * Handle the loading/unloading of a netgraph node type module 2891 */ 2892 int 2893 ng_mod_event(module_t mod, int event, void *data) 2894 { 2895 struct ng_type *const type = data; 2896 int s, error = 0; 2897 2898 switch (event) { 2899 case MOD_LOAD: 2900 2901 /* Register new netgraph node type */ 2902 s = splnet(); 2903 if ((error = ng_newtype(type)) != 0) { 2904 splx(s); 2905 break; 2906 } 2907 2908 /* Call type specific code */ 2909 if (type->mod_event != NULL) 2910 if ((error = (*type->mod_event)(mod, event, data))) { 2911 mtx_lock(&ng_typelist_mtx); 2912 type->refs--; /* undo it */ 2913 LIST_REMOVE(type, types); 2914 mtx_unlock(&ng_typelist_mtx); 2915 } 2916 splx(s); 2917 break; 2918 2919 case MOD_UNLOAD: 2920 s = splnet(); 2921 if (type->refs > 1) { /* make sure no nodes exist! */ 2922 error = EBUSY; 2923 } else { 2924 if (type->refs == 0) { 2925 /* failed load, nothing to undo */ 2926 splx(s); 2927 break; 2928 } 2929 if (type->mod_event != NULL) { /* check with type */ 2930 error = (*type->mod_event)(mod, event, data); 2931 if (error != 0) { /* type refuses.. */ 2932 splx(s); 2933 break; 2934 } 2935 } 2936 mtx_lock(&ng_typelist_mtx); 2937 LIST_REMOVE(type, types); 2938 mtx_unlock(&ng_typelist_mtx); 2939 } 2940 splx(s); 2941 break; 2942 2943 default: 2944 if (type->mod_event != NULL) 2945 error = (*type->mod_event)(mod, event, data); 2946 else 2947 error = EOPNOTSUPP; /* XXX ? */ 2948 break; 2949 } 2950 return (error); 2951 } 2952 2953 /* 2954 * Handle loading and unloading for this code. 2955 * The only thing we need to link into is the NETISR strucure. 2956 */ 2957 static int 2958 ngb_mod_event(module_t mod, int event, void *data) 2959 { 2960 int s, error = 0; 2961 2962 switch (event) { 2963 case MOD_LOAD: 2964 /* Register line discipline */ 2965 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_SPIN); 2966 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL, 2967 MTX_DEF); 2968 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL, 2969 MTX_DEF); 2970 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL, 2971 MTX_DEF); 2972 mtx_init(&ngq_mtx, "netgraph free item list mutex", NULL, 2973 MTX_DEF); 2974 s = splimp(); 2975 /* XXX could use NETISR_MPSAFE but need to verify code */ 2976 netisr_register(NETISR_NETGRAPH, (netisr_t *)ngintr, NULL, 0); 2977 splx(s); 2978 break; 2979 case MOD_UNLOAD: 2980 /* You cant unload it because an interface may be using it. */ 2981 error = EBUSY; 2982 break; 2983 default: 2984 error = EOPNOTSUPP; 2985 break; 2986 } 2987 return (error); 2988 } 2989 2990 static moduledata_t netgraph_mod = { 2991 "netgraph", 2992 ngb_mod_event, 2993 (NULL) 2994 }; 2995 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE); 2996 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family"); 2997 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,""); 2998 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, ""); 2999 3000 /************************************************************************ 3001 Queue element get/free routines 3002 ************************************************************************/ 3003 3004 3005 static int allocated; /* number of items malloc'd */ 3006 3007 static int maxalloc = 128; /* limit the damage of a leak */ 3008 static int ngqfreemax = 64;/* cache at most this many */ 3009 3010 TUNABLE_INT("net.graph.maxalloc", &maxalloc); 3011 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc, 3012 0, "Maximum number of queue items to allocate"); 3013 3014 TUNABLE_INT("net.graph.ngqfreemax", &ngqfreemax); 3015 SYSCTL_INT(_net_graph, OID_AUTO, ngqfreemax, CTLFLAG_RDTUN, &ngqfreemax, 3016 0, "Maximum number of free queue items to cache"); 3017 3018 static const int ngqfreelow = 4; /* try malloc if free < this */ 3019 static volatile int ngqfreesize; /* number of cached entries */ 3020 static volatile item_p ngqfree; /* free ones */ 3021 3022 #ifdef NETGRAPH_DEBUG 3023 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist); 3024 #endif 3025 /* 3026 * Get a queue entry 3027 * This is usually called when a packet first enters netgraph. 3028 * By definition, this is usually from an interrupt, or from a user. 3029 * Users are not so important, but try be quick for the times that it's 3030 * an interrupt. 3031 * XXX If reserve is low, we should try to get 2 from malloc as this 3032 * would indicate it often fails. 3033 */ 3034 static item_p 3035 ng_getqblk(void) 3036 { 3037 item_p item = NULL; 3038 3039 /* 3040 * Try get a cached queue block, or else allocate a new one 3041 * If we are less than our reserve, try malloc. If malloc 3042 * fails, then that's what the reserve is for... 3043 * We have our little reserve 3044 * because we use M_NOWAIT for malloc. This just helps us 3045 * avoid dropping packets while not increasing the time 3046 * we take to service the interrupt (on average) (I hope). 3047 */ 3048 mtx_lock(&ngq_mtx); 3049 3050 if ((ngqfreesize < ngqfreelow) || (ngqfree == NULL)) { 3051 if (allocated < maxalloc) { /* don't leak forever */ 3052 MALLOC(item, item_p , 3053 sizeof(*item), M_NETGRAPH_ITEM, 3054 (M_NOWAIT | M_ZERO)); 3055 if (item) { 3056 #ifdef NETGRAPH_DEBUG 3057 TAILQ_INSERT_TAIL(&ng_itemlist, item, all); 3058 #endif /* NETGRAPH_DEBUG */ 3059 allocated++; 3060 } 3061 } 3062 } 3063 3064 /* 3065 * We didn't or couldn't malloc. 3066 * try get one from our cache. 3067 */ 3068 if (item == NULL && (item = ngqfree) != NULL) { 3069 ngqfree = item->el_next; 3070 ngqfreesize--; 3071 item->el_flags &= ~NGQF_FREE; 3072 } 3073 3074 mtx_unlock(&ngq_mtx); 3075 return (item); 3076 } 3077 3078 /* 3079 * Release a queue entry 3080 */ 3081 void 3082 ng_free_item(item_p item) 3083 { 3084 3085 /* 3086 * The item may hold resources on it's own. We need to free 3087 * these before we can free the item. What they are depends upon 3088 * what kind of item it is. it is important that nodes zero 3089 * out pointers to resources that they remove from the item 3090 * or we release them again here. 3091 */ 3092 if (item->el_flags & NGQF_FREE) { 3093 panic(" Freeing free queue item"); 3094 } 3095 switch (item->el_flags & NGQF_TYPE) { 3096 case NGQF_DATA: 3097 /* If we have an mbuf still attached.. */ 3098 NG_FREE_M(_NGI_M(item)); 3099 break; 3100 case NGQF_MESG: 3101 _NGI_RETADDR(item) = 0; 3102 NG_FREE_MSG(_NGI_MSG(item)); 3103 break; 3104 case NGQF_FN: 3105 /* nothing to free really, */ 3106 _NGI_FN(item) = NULL; 3107 _NGI_ARG1(item) = NULL; 3108 _NGI_ARG2(item) = 0; 3109 case NGQF_UNDEF: 3110 break; 3111 } 3112 /* If we still have a node or hook referenced... */ 3113 _NGI_CLR_NODE(item); 3114 _NGI_CLR_HOOK(item); 3115 item->el_flags |= NGQF_FREE; 3116 3117 mtx_lock(&ngq_mtx); 3118 if (ngqfreesize < ngqfreemax) { 3119 ngqfreesize++; 3120 item->el_next = ngqfree; 3121 ngqfree = item; 3122 } else { 3123 #ifdef NETGRAPH_DEBUG 3124 TAILQ_REMOVE(&ng_itemlist, item, all); 3125 #endif /* NETGRAPH_DEBUG */ 3126 NG_FREE_ITEM_REAL(item); 3127 allocated--; 3128 } 3129 mtx_unlock(&ngq_mtx); 3130 } 3131 3132 #ifdef NETGRAPH_DEBUG 3133 void 3134 dumphook (hook_p hook, char *file, int line) 3135 { 3136 printf("hook: name %s, %d refs, Last touched:\n", 3137 _NG_HOOK_NAME(hook), hook->hk_refs); 3138 printf(" Last active @ %s, line %d\n", 3139 hook->lastfile, hook->lastline); 3140 if (line) { 3141 printf(" problem discovered at file %s, line %d\n", file, line); 3142 } 3143 } 3144 3145 void 3146 dumpnode(node_p node, char *file, int line) 3147 { 3148 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n", 3149 _NG_NODE_ID(node), node->nd_type->name, 3150 node->nd_numhooks, node->nd_flags, 3151 node->nd_refs, node->nd_name); 3152 printf(" Last active @ %s, line %d\n", 3153 node->lastfile, node->lastline); 3154 if (line) { 3155 printf(" problem discovered at file %s, line %d\n", file, line); 3156 } 3157 } 3158 3159 void 3160 dumpitem(item_p item, char *file, int line) 3161 { 3162 if (item->el_flags & NGQF_FREE) { 3163 printf(" Free item, freed at %s, line %d\n", 3164 item->lastfile, item->lastline); 3165 } else { 3166 printf(" ACTIVE item, last used at %s, line %d", 3167 item->lastfile, item->lastline); 3168 switch(item->el_flags & NGQF_TYPE) { 3169 case NGQF_DATA: 3170 printf(" - [data]\n"); 3171 break; 3172 case NGQF_MESG: 3173 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item)); 3174 break; 3175 case NGQF_FN: 3176 printf(" - fn@%p (%p, %p, %p, %d (%x))\n", 3177 item->body.fn.fn_fn, 3178 NGI_NODE(item), 3179 NGI_HOOK(item), 3180 item->body.fn.fn_arg1, 3181 item->body.fn.fn_arg2, 3182 item->body.fn.fn_arg2); 3183 break; 3184 case NGQF_UNDEF: 3185 printf(" - UNDEFINED!\n"); 3186 } 3187 } 3188 if (line) { 3189 printf(" problem discovered at file %s, line %d\n", file, line); 3190 if (NGI_NODE(item)) { 3191 printf("node %p ([%x])\n", 3192 NGI_NODE(item), ng_node2ID(NGI_NODE(item))); 3193 } 3194 } 3195 } 3196 3197 static void 3198 ng_dumpitems(void) 3199 { 3200 item_p item; 3201 int i = 1; 3202 TAILQ_FOREACH(item, &ng_itemlist, all) { 3203 printf("[%d] ", i++); 3204 dumpitem(item, NULL, 0); 3205 } 3206 } 3207 3208 static void 3209 ng_dumpnodes(void) 3210 { 3211 node_p node; 3212 int i = 1; 3213 mtx_lock(&ng_nodelist_mtx); 3214 SLIST_FOREACH(node, &ng_allnodes, nd_all) { 3215 printf("[%d] ", i++); 3216 dumpnode(node, NULL, 0); 3217 } 3218 mtx_unlock(&ng_nodelist_mtx); 3219 } 3220 3221 static void 3222 ng_dumphooks(void) 3223 { 3224 hook_p hook; 3225 int i = 1; 3226 mtx_lock(&ng_nodelist_mtx); 3227 SLIST_FOREACH(hook, &ng_allhooks, hk_all) { 3228 printf("[%d] ", i++); 3229 dumphook(hook, NULL, 0); 3230 } 3231 mtx_unlock(&ng_nodelist_mtx); 3232 } 3233 3234 static int 3235 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS) 3236 { 3237 int error; 3238 int val; 3239 int i; 3240 3241 val = allocated; 3242 i = 1; 3243 error = sysctl_handle_int(oidp, &val, sizeof(int), req); 3244 if (error != 0 || req->newptr == NULL) 3245 return (error); 3246 if (val == 42) { 3247 ng_dumpitems(); 3248 ng_dumpnodes(); 3249 ng_dumphooks(); 3250 } 3251 return (0); 3252 } 3253 3254 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW, 3255 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items"); 3256 #endif /* NETGRAPH_DEBUG */ 3257 3258 3259 /*********************************************************************** 3260 * Worklist routines 3261 **********************************************************************/ 3262 /* NETISR thread enters here */ 3263 /* 3264 * Pick a node off the list of nodes with work, 3265 * try get an item to process off it. 3266 * If there are no more, remove the node from the list. 3267 */ 3268 static void 3269 ngintr(void) 3270 { 3271 item_p item; 3272 node_p node = NULL; 3273 3274 for (;;) { 3275 mtx_lock_spin(&ng_worklist_mtx); 3276 node = TAILQ_FIRST(&ng_worklist); 3277 if (!node) { 3278 mtx_unlock_spin(&ng_worklist_mtx); 3279 break; 3280 } 3281 node->nd_flags &= ~NGF_WORKQ; 3282 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3283 mtx_unlock_spin(&ng_worklist_mtx); 3284 /* 3285 * We have the node. We also take over the reference 3286 * that the list had on it. 3287 * Now process as much as you can, until it won't 3288 * let you have another item off the queue. 3289 * All this time, keep the reference 3290 * that lets us be sure that the node still exists. 3291 * Let the reference go at the last minute. 3292 * ng_dequeue will put us back on the worklist 3293 * if there is more too do. This may be of use if there 3294 * are Multiple Processors and multiple Net threads in the 3295 * future. 3296 */ 3297 for (;;) { 3298 mtx_lock_spin(&node->nd_input_queue.q_mtx); 3299 item = ng_dequeue(&node->nd_input_queue); 3300 if (item == NULL) { 3301 mtx_unlock_spin(&node->nd_input_queue.q_mtx); 3302 break; /* go look for another node */ 3303 } else { 3304 mtx_unlock_spin(&node->nd_input_queue.q_mtx); 3305 NGI_GET_NODE(item, node); /* zaps stored node */ 3306 ng_apply_item(node, item); 3307 NG_NODE_UNREF(node); 3308 } 3309 } 3310 NG_NODE_UNREF(node); 3311 } 3312 } 3313 3314 static void 3315 ng_worklist_remove(node_p node) 3316 { 3317 mtx_lock_spin(&ng_worklist_mtx); 3318 if (node->nd_flags & NGF_WORKQ) { 3319 node->nd_flags &= ~NGF_WORKQ; 3320 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3321 mtx_unlock_spin(&ng_worklist_mtx); 3322 NG_NODE_UNREF(node); 3323 } else { 3324 mtx_unlock_spin(&ng_worklist_mtx); 3325 } 3326 } 3327 3328 /* 3329 * XXX 3330 * It's posible that a debugging NG_NODE_REF may need 3331 * to be outside the mutex zone 3332 */ 3333 static void 3334 ng_setisr(node_p node) 3335 { 3336 mtx_lock_spin(&ng_worklist_mtx); 3337 if ((node->nd_flags & NGF_WORKQ) == 0) { 3338 /* 3339 * If we are not already on the work queue, 3340 * then put us on. 3341 */ 3342 node->nd_flags |= NGF_WORKQ; 3343 TAILQ_INSERT_TAIL(&ng_worklist, node, nd_work); 3344 NG_NODE_REF(node); /* XXX fafe in mutex? */ 3345 } 3346 mtx_unlock_spin(&ng_worklist_mtx); 3347 schednetisr(NETISR_NETGRAPH); 3348 } 3349 3350 3351 /*********************************************************************** 3352 * Externally useable functions to set up a queue item ready for sending 3353 ***********************************************************************/ 3354 3355 #ifdef NETGRAPH_DEBUG 3356 #define ITEM_DEBUG_CHECKS \ 3357 do { \ 3358 if (NGI_NODE(item) ) { \ 3359 printf("item already has node"); \ 3360 kdb_enter("has node"); \ 3361 NGI_CLR_NODE(item); \ 3362 } \ 3363 if (NGI_HOOK(item) ) { \ 3364 printf("item already has hook"); \ 3365 kdb_enter("has hook"); \ 3366 NGI_CLR_HOOK(item); \ 3367 } \ 3368 } while (0) 3369 #else 3370 #define ITEM_DEBUG_CHECKS 3371 #endif 3372 3373 /* 3374 * Put mbuf into the item. 3375 * Hook and node references will be removed when the item is dequeued. 3376 * (or equivalent) 3377 * (XXX) Unsafe because no reference held by peer on remote node. 3378 * remote node might go away in this timescale. 3379 * We know the hooks can't go away because that would require getting 3380 * a writer item on both nodes and we must have at least a reader 3381 * here to eb able to do this. 3382 * Note that the hook loaded is the REMOTE hook. 3383 * 3384 * This is possibly in the critical path for new data. 3385 */ 3386 item_p 3387 ng_package_data(struct mbuf *m, void *dummy) 3388 { 3389 item_p item; 3390 3391 if ((item = ng_getqblk()) == NULL) { 3392 NG_FREE_M(m); 3393 return (NULL); 3394 } 3395 ITEM_DEBUG_CHECKS; 3396 item->el_flags = NGQF_DATA; 3397 item->el_next = NULL; 3398 NGI_M(item) = m; 3399 return (item); 3400 } 3401 3402 /* 3403 * Allocate a queue item and put items into it.. 3404 * Evaluate the address as this will be needed to queue it and 3405 * to work out what some of the fields should be. 3406 * Hook and node references will be removed when the item is dequeued. 3407 * (or equivalent) 3408 */ 3409 item_p 3410 ng_package_msg(struct ng_mesg *msg) 3411 { 3412 item_p item; 3413 3414 if ((item = ng_getqblk()) == NULL) { 3415 NG_FREE_MSG(msg); 3416 return (NULL); 3417 } 3418 ITEM_DEBUG_CHECKS; 3419 item->el_flags = NGQF_MESG; 3420 item->el_next = NULL; 3421 /* 3422 * Set the current lasthook into the queue item 3423 */ 3424 NGI_MSG(item) = msg; 3425 NGI_RETADDR(item) = 0; 3426 return (item); 3427 } 3428 3429 3430 3431 #define SET_RETADDR(item, here, retaddr) \ 3432 do { /* Data or fn items don't have retaddrs */ \ 3433 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \ 3434 if (retaddr) { \ 3435 NGI_RETADDR(item) = retaddr; \ 3436 } else { \ 3437 /* \ 3438 * The old return address should be ok. \ 3439 * If there isn't one, use the address \ 3440 * here. \ 3441 */ \ 3442 if (NGI_RETADDR(item) == 0) { \ 3443 NGI_RETADDR(item) \ 3444 = ng_node2ID(here); \ 3445 } \ 3446 } \ 3447 } \ 3448 } while (0) 3449 3450 int 3451 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr) 3452 { 3453 hook_p peer; 3454 node_p peernode; 3455 ITEM_DEBUG_CHECKS; 3456 /* 3457 * Quick sanity check.. 3458 * Since a hook holds a reference on it's node, once we know 3459 * that the peer is still connected (even if invalid,) we know 3460 * that the peer node is present, though maybe invalid. 3461 */ 3462 if ((hook == NULL) 3463 || NG_HOOK_NOT_VALID(hook) 3464 || (NG_HOOK_PEER(hook) == NULL) 3465 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)) 3466 || NG_NODE_NOT_VALID(NG_PEER_NODE(hook))) { 3467 NG_FREE_ITEM(item); 3468 TRAP_ERROR(); 3469 return (ENETDOWN); 3470 } 3471 3472 /* 3473 * Transfer our interest to the other (peer) end. 3474 */ 3475 peer = NG_HOOK_PEER(hook); 3476 NG_HOOK_REF(peer); 3477 NGI_SET_HOOK(item, peer); 3478 peernode = NG_PEER_NODE(hook); 3479 NG_NODE_REF(peernode); 3480 NGI_SET_NODE(item, peernode); 3481 SET_RETADDR(item, here, retaddr); 3482 return (0); 3483 } 3484 3485 int 3486 ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr) 3487 { 3488 node_p dest = NULL; 3489 hook_p hook = NULL; 3490 int error; 3491 3492 ITEM_DEBUG_CHECKS; 3493 /* 3494 * Note that ng_path2noderef increments the reference count 3495 * on the node for us if it finds one. So we don't have to. 3496 */ 3497 error = ng_path2noderef(here, address, &dest, &hook); 3498 if (error) { 3499 NG_FREE_ITEM(item); 3500 return (error); 3501 } 3502 NGI_SET_NODE(item, dest); 3503 if ( hook) { 3504 NG_HOOK_REF(hook); /* don't let it go while on the queue */ 3505 NGI_SET_HOOK(item, hook); 3506 } 3507 SET_RETADDR(item, here, retaddr); 3508 return (0); 3509 } 3510 3511 int 3512 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr) 3513 { 3514 node_p dest; 3515 3516 ITEM_DEBUG_CHECKS; 3517 /* 3518 * Find the target node. 3519 */ 3520 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */ 3521 if (dest == NULL) { 3522 NG_FREE_ITEM(item); 3523 TRAP_ERROR(); 3524 return(EINVAL); 3525 } 3526 /* Fill out the contents */ 3527 item->el_flags = NGQF_MESG; 3528 item->el_next = NULL; 3529 NGI_SET_NODE(item, dest); 3530 NGI_CLR_HOOK(item); 3531 SET_RETADDR(item, here, retaddr); 3532 return (0); 3533 } 3534 3535 /* 3536 * special case to send a message to self (e.g. destroy node) 3537 * Possibly indicate an arrival hook too. 3538 * Useful for removing that hook :-) 3539 */ 3540 item_p 3541 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg) 3542 { 3543 item_p item; 3544 3545 /* 3546 * Find the target node. 3547 * If there is a HOOK argument, then use that in preference 3548 * to the address. 3549 */ 3550 if ((item = ng_getqblk()) == NULL) { 3551 NG_FREE_MSG(msg); 3552 return (NULL); 3553 } 3554 3555 /* Fill out the contents */ 3556 item->el_flags = NGQF_MESG; 3557 item->el_next = NULL; 3558 NG_NODE_REF(here); 3559 NGI_SET_NODE(item, here); 3560 if (hook) { 3561 NG_HOOK_REF(hook); 3562 NGI_SET_HOOK(item, hook); 3563 } 3564 NGI_MSG(item) = msg; 3565 NGI_RETADDR(item) = ng_node2ID(here); 3566 return (item); 3567 } 3568 3569 int 3570 ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2) 3571 { 3572 item_p item; 3573 3574 if ((item = ng_getqblk()) == NULL) { 3575 return (ENOMEM); 3576 } 3577 item->el_flags = NGQF_FN | NGQF_WRITER; 3578 NG_NODE_REF(node); /* and one for the item */ 3579 NGI_SET_NODE(item, node); 3580 if (hook) { 3581 NG_HOOK_REF(hook); 3582 NGI_SET_HOOK(item, hook); 3583 } 3584 NGI_FN(item) = fn; 3585 NGI_ARG1(item) = arg1; 3586 NGI_ARG2(item) = arg2; 3587 return(ng_snd_item(item, 0)); 3588 } 3589 3590 /* 3591 * Official timeout routines for Netgraph nodes. 3592 */ 3593 static void 3594 ng_callout_trapoline(void *arg) 3595 { 3596 item_p item = arg; 3597 3598 ng_snd_item(item, 0); 3599 } 3600 3601 3602 int 3603 ng_callout(struct callout *c, node_p node, hook_p hook, int ticks, 3604 ng_item_fn *fn, void * arg1, int arg2) 3605 { 3606 item_p item; 3607 3608 if ((item = ng_getqblk()) == NULL) 3609 return (ENOMEM); 3610 3611 item->el_flags = NGQF_FN | NGQF_WRITER; 3612 NG_NODE_REF(node); /* and one for the item */ 3613 NGI_SET_NODE(item, node); 3614 if (hook) { 3615 NG_HOOK_REF(hook); 3616 NGI_SET_HOOK(item, hook); 3617 } 3618 NGI_FN(item) = fn; 3619 NGI_ARG1(item) = arg1; 3620 NGI_ARG2(item) = arg2; 3621 callout_reset(c, ticks, &ng_callout_trapoline, item); 3622 return (0); 3623 } 3624 3625 /* A special modified version of untimeout() */ 3626 int 3627 ng_uncallout(struct callout *c, node_p node) 3628 { 3629 item_p item; 3630 int rval; 3631 void *c_func; 3632 3633 if (c == NULL) 3634 return (0); 3635 /* there must be an official way to do this */ 3636 mtx_lock_spin(&callout_lock); 3637 c_func = c->c_func; 3638 rval = callout_stop(c); 3639 mtx_unlock_spin(&callout_lock); 3640 item = c->c_arg; 3641 /* Do an extra check */ 3642 if ((rval > 0) && (c_func == &ng_callout_trapoline) && 3643 (NGI_NODE(item) == node)) { 3644 /* 3645 * We successfully removed it from the queue before it ran 3646 * So now we need to unreference everything that was 3647 * given extra references. (NG_FREE_ITEM does this). 3648 */ 3649 NG_FREE_ITEM(item); 3650 } 3651 3652 return (rval); 3653 } 3654 3655 /* 3656 * Set the address, if none given, give the node here. 3657 */ 3658 void 3659 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr) 3660 { 3661 if (retaddr) { 3662 NGI_RETADDR(item) = retaddr; 3663 } else { 3664 /* 3665 * The old return address should be ok. 3666 * If there isn't one, use the address here. 3667 */ 3668 NGI_RETADDR(item) = ng_node2ID(here); 3669 } 3670 } 3671 3672 #define TESTING 3673 #ifdef TESTING 3674 /* just test all the macros */ 3675 void 3676 ng_macro_test(item_p item); 3677 void 3678 ng_macro_test(item_p item) 3679 { 3680 node_p node = NULL; 3681 hook_p hook = NULL; 3682 struct mbuf *m; 3683 struct ng_mesg *msg; 3684 ng_ID_t retaddr; 3685 int error; 3686 3687 NGI_GET_M(item, m); 3688 NGI_GET_MSG(item, msg); 3689 retaddr = NGI_RETADDR(item); 3690 NG_SEND_DATA(error, hook, m, NULL); 3691 NG_SEND_DATA_ONLY(error, hook, m); 3692 NG_FWD_NEW_DATA(error, item, hook, m); 3693 NG_FWD_ITEM_HOOK(error, item, hook); 3694 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr); 3695 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr); 3696 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr); 3697 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr); 3698 } 3699 #endif /* TESTING */ 3700 3701