1 /* 2 * ng_base.c 3 */ 4 5 /*- 6 * Copyright (c) 1996-1999 Whistle Communications, Inc. 7 * All rights reserved. 8 * 9 * Subject to the following obligations and disclaimer of warranty, use and 10 * redistribution of this software, in source or object code forms, with or 11 * without modifications are expressly permitted by Whistle Communications; 12 * provided, however, that: 13 * 1. Any and all reproductions of the source or object code must include the 14 * copyright notice above and the following disclaimer of warranties; and 15 * 2. No rights are granted, in any manner or form, to use Whistle 16 * Communications, Inc. trademarks, including the mark "WHISTLE 17 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 18 * such appears in the above copyright notice or in the software. 19 * 20 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 21 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 22 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 23 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 25 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 26 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 27 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 28 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 29 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 30 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 31 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 32 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 35 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 36 * OF SUCH DAMAGE. 37 * 38 * Authors: Julian Elischer <julian@freebsd.org> 39 * Archie Cobbs <archie@freebsd.org> 40 * 41 * $FreeBSD$ 42 * $Whistle: ng_base.c,v 1.39 1999/01/28 23:54:53 julian Exp $ 43 */ 44 45 /* 46 * This file implements the base netgraph code. 47 */ 48 49 #include <sys/param.h> 50 #include <sys/systm.h> 51 #include <sys/ctype.h> 52 #include <sys/errno.h> 53 #include <sys/kdb.h> 54 #include <sys/kernel.h> 55 #include <sys/ktr.h> 56 #include <sys/limits.h> 57 #include <sys/malloc.h> 58 #include <sys/mbuf.h> 59 #include <sys/queue.h> 60 #include <sys/sysctl.h> 61 #include <sys/syslog.h> 62 63 #include <net/netisr.h> 64 65 #include <netgraph/ng_message.h> 66 #include <netgraph/netgraph.h> 67 #include <netgraph/ng_parse.h> 68 69 MODULE_VERSION(netgraph, NG_ABI_VERSION); 70 71 /* List of all active nodes */ 72 static LIST_HEAD(, ng_node) ng_nodelist; 73 static struct mtx ng_nodelist_mtx; 74 75 /* Mutex to protect topology events. */ 76 static struct mtx ng_topo_mtx; 77 78 #ifdef NETGRAPH_DEBUG 79 static struct mtx ngq_mtx; /* protects the queue item list */ 80 81 static SLIST_HEAD(, ng_node) ng_allnodes; 82 static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */ 83 static SLIST_HEAD(, ng_hook) ng_allhooks; 84 static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */ 85 86 static void ng_dumpitems(void); 87 static void ng_dumpnodes(void); 88 static void ng_dumphooks(void); 89 90 #endif /* NETGRAPH_DEBUG */ 91 /* 92 * DEAD versions of the structures. 93 * In order to avoid races, it is sometimes neccesary to point 94 * at SOMETHING even though theoretically, the current entity is 95 * INVALID. Use these to avoid these races. 96 */ 97 struct ng_type ng_deadtype = { 98 NG_ABI_VERSION, 99 "dead", 100 NULL, /* modevent */ 101 NULL, /* constructor */ 102 NULL, /* rcvmsg */ 103 NULL, /* shutdown */ 104 NULL, /* newhook */ 105 NULL, /* findhook */ 106 NULL, /* connect */ 107 NULL, /* rcvdata */ 108 NULL, /* disconnect */ 109 NULL, /* cmdlist */ 110 }; 111 112 struct ng_node ng_deadnode = { 113 "dead", 114 &ng_deadtype, 115 NGF_INVALID, 116 1, /* refs */ 117 0, /* numhooks */ 118 NULL, /* private */ 119 0, /* ID */ 120 LIST_HEAD_INITIALIZER(ng_deadnode.hooks), 121 {}, /* all_nodes list entry */ 122 {}, /* id hashtable list entry */ 123 {}, /* workqueue entry */ 124 { 0, 125 {}, /* should never use! (should hang) */ 126 NULL, 127 &ng_deadnode.nd_input_queue.queue, 128 &ng_deadnode 129 }, 130 #ifdef NETGRAPH_DEBUG 131 ND_MAGIC, 132 __FILE__, 133 __LINE__, 134 {NULL} 135 #endif /* NETGRAPH_DEBUG */ 136 }; 137 138 struct ng_hook ng_deadhook = { 139 "dead", 140 NULL, /* private */ 141 HK_INVALID | HK_DEAD, 142 1, /* refs always >= 1 */ 143 0, /* undefined data link type */ 144 &ng_deadhook, /* Peer is self */ 145 &ng_deadnode, /* attached to deadnode */ 146 {}, /* hooks list */ 147 NULL, /* override rcvmsg() */ 148 NULL, /* override rcvdata() */ 149 #ifdef NETGRAPH_DEBUG 150 HK_MAGIC, 151 __FILE__, 152 __LINE__, 153 {NULL} 154 #endif /* NETGRAPH_DEBUG */ 155 }; 156 157 /* 158 * END DEAD STRUCTURES 159 */ 160 /* List nodes with unallocated work */ 161 static TAILQ_HEAD(, ng_node) ng_worklist = TAILQ_HEAD_INITIALIZER(ng_worklist); 162 static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */ 163 164 /* List of installed types */ 165 static LIST_HEAD(, ng_type) ng_typelist; 166 static struct mtx ng_typelist_mtx; 167 168 /* Hash related definitions */ 169 /* XXX Don't need to initialise them because it's a LIST */ 170 #define NG_ID_HASH_SIZE 32 /* most systems wont need even this many */ 171 static LIST_HEAD(, ng_node) ng_ID_hash[NG_ID_HASH_SIZE]; 172 static struct mtx ng_idhash_mtx; 173 /* Method to find a node.. used twice so do it here */ 174 #define NG_IDHASH_FN(ID) ((ID) % (NG_ID_HASH_SIZE)) 175 #define NG_IDHASH_FIND(ID, node) \ 176 do { \ 177 mtx_assert(&ng_idhash_mtx, MA_OWNED); \ 178 LIST_FOREACH(node, &ng_ID_hash[NG_IDHASH_FN(ID)], \ 179 nd_idnodes) { \ 180 if (NG_NODE_IS_VALID(node) \ 181 && (NG_NODE_ID(node) == ID)) { \ 182 break; \ 183 } \ 184 } \ 185 } while (0) 186 187 188 /* Internal functions */ 189 static int ng_add_hook(node_p node, const char *name, hook_p * hookp); 190 static int ng_generic_msg(node_p here, item_p item, hook_p lasthook); 191 static ng_ID_t ng_decodeidname(const char *name); 192 static int ngb_mod_event(module_t mod, int event, void *data); 193 static void ng_worklist_remove(node_p node); 194 static void ngintr(void); 195 static int ng_apply_item(node_p node, item_p item, int rw); 196 static void ng_flush_input_queue(struct ng_queue * ngq); 197 static void ng_setisr(node_p node); 198 static node_p ng_ID2noderef(ng_ID_t ID); 199 static int ng_con_nodes(node_p node, const char *name, node_p node2, 200 const char *name2); 201 static void ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2); 202 static void ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2); 203 static int ng_mkpeer(node_p node, const char *name, 204 const char *name2, char *type); 205 206 /* Imported, these used to be externally visible, some may go back. */ 207 void ng_destroy_hook(hook_p hook); 208 node_p ng_name2noderef(node_p node, const char *name); 209 int ng_path2noderef(node_p here, const char *path, 210 node_p *dest, hook_p *lasthook); 211 int ng_make_node(const char *type, node_p *nodepp); 212 int ng_path_parse(char *addr, char **node, char **path, char **hook); 213 void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3); 214 void ng_unname(node_p node); 215 216 217 /* Our own netgraph malloc type */ 218 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages"); 219 MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures"); 220 MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures"); 221 MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", "netgraph item structures"); 222 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage"); 223 224 /* Should not be visible outside this file */ 225 226 #define _NG_ALLOC_HOOK(hook) \ 227 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO) 228 #define _NG_ALLOC_NODE(node) \ 229 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO) 230 231 #define NG_QUEUE_LOCK_INIT(n) \ 232 mtx_init(&(n)->q_mtx, "ng_node", NULL, MTX_DEF) 233 #define NG_QUEUE_LOCK(n) \ 234 mtx_lock(&(n)->q_mtx) 235 #define NG_QUEUE_UNLOCK(n) \ 236 mtx_unlock(&(n)->q_mtx) 237 #define NG_WORKLIST_LOCK_INIT() \ 238 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_DEF) 239 #define NG_WORKLIST_LOCK() \ 240 mtx_lock(&ng_worklist_mtx) 241 #define NG_WORKLIST_UNLOCK() \ 242 mtx_unlock(&ng_worklist_mtx) 243 244 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/ 245 /* 246 * In debug mode: 247 * In an attempt to help track reference count screwups 248 * we do not free objects back to the malloc system, but keep them 249 * in a local cache where we can examine them and keep information safely 250 * after they have been freed. 251 * We use this scheme for nodes and hooks, and to some extent for items. 252 */ 253 static __inline hook_p 254 ng_alloc_hook(void) 255 { 256 hook_p hook; 257 SLIST_ENTRY(ng_hook) temp; 258 mtx_lock(&ng_nodelist_mtx); 259 hook = LIST_FIRST(&ng_freehooks); 260 if (hook) { 261 LIST_REMOVE(hook, hk_hooks); 262 bcopy(&hook->hk_all, &temp, sizeof(temp)); 263 bzero(hook, sizeof(struct ng_hook)); 264 bcopy(&temp, &hook->hk_all, sizeof(temp)); 265 mtx_unlock(&ng_nodelist_mtx); 266 hook->hk_magic = HK_MAGIC; 267 } else { 268 mtx_unlock(&ng_nodelist_mtx); 269 _NG_ALLOC_HOOK(hook); 270 if (hook) { 271 hook->hk_magic = HK_MAGIC; 272 mtx_lock(&ng_nodelist_mtx); 273 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all); 274 mtx_unlock(&ng_nodelist_mtx); 275 } 276 } 277 return (hook); 278 } 279 280 static __inline node_p 281 ng_alloc_node(void) 282 { 283 node_p node; 284 SLIST_ENTRY(ng_node) temp; 285 mtx_lock(&ng_nodelist_mtx); 286 node = LIST_FIRST(&ng_freenodes); 287 if (node) { 288 LIST_REMOVE(node, nd_nodes); 289 bcopy(&node->nd_all, &temp, sizeof(temp)); 290 bzero(node, sizeof(struct ng_node)); 291 bcopy(&temp, &node->nd_all, sizeof(temp)); 292 mtx_unlock(&ng_nodelist_mtx); 293 node->nd_magic = ND_MAGIC; 294 } else { 295 mtx_unlock(&ng_nodelist_mtx); 296 _NG_ALLOC_NODE(node); 297 if (node) { 298 node->nd_magic = ND_MAGIC; 299 mtx_lock(&ng_nodelist_mtx); 300 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all); 301 mtx_unlock(&ng_nodelist_mtx); 302 } 303 } 304 return (node); 305 } 306 307 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0) 308 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0) 309 310 311 #define NG_FREE_HOOK(hook) \ 312 do { \ 313 mtx_lock(&ng_nodelist_mtx); \ 314 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \ 315 hook->hk_magic = 0; \ 316 mtx_unlock(&ng_nodelist_mtx); \ 317 } while (0) 318 319 #define NG_FREE_NODE(node) \ 320 do { \ 321 mtx_lock(&ng_nodelist_mtx); \ 322 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \ 323 node->nd_magic = 0; \ 324 mtx_unlock(&ng_nodelist_mtx); \ 325 } while (0) 326 327 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 328 329 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook) 330 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node) 331 332 #define NG_FREE_HOOK(hook) do { FREE((hook), M_NETGRAPH_HOOK); } while (0) 333 #define NG_FREE_NODE(node) do { FREE((node), M_NETGRAPH_NODE); } while (0) 334 335 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 336 337 /* Set this to kdb_enter("X") to catch all errors as they occur */ 338 #ifndef TRAP_ERROR 339 #define TRAP_ERROR() 340 #endif 341 342 static ng_ID_t nextID = 1; 343 344 #ifdef INVARIANTS 345 #define CHECK_DATA_MBUF(m) do { \ 346 struct mbuf *n; \ 347 int total; \ 348 \ 349 M_ASSERTPKTHDR(m); \ 350 for (total = 0, n = (m); n != NULL; n = n->m_next) { \ 351 total += n->m_len; \ 352 if (n->m_nextpkt != NULL) \ 353 panic("%s: m_nextpkt", __func__); \ 354 } \ 355 \ 356 if ((m)->m_pkthdr.len != total) { \ 357 panic("%s: %d != %d", \ 358 __func__, (m)->m_pkthdr.len, total); \ 359 } \ 360 } while (0) 361 #else 362 #define CHECK_DATA_MBUF(m) 363 #endif 364 365 366 /************************************************************************ 367 Parse type definitions for generic messages 368 ************************************************************************/ 369 370 /* Handy structure parse type defining macro */ 371 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \ 372 static const struct ng_parse_struct_field \ 373 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \ 374 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \ 375 &ng_parse_struct_type, \ 376 &ng_ ## lo ## _type_fields \ 377 } 378 379 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ()); 380 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ()); 381 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ()); 382 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ()); 383 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ()); 384 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ()); 385 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type)); 386 387 /* Get length of an array when the length is stored as a 32 bit 388 value immediately preceding the array -- as with struct namelist 389 and struct typelist. */ 390 static int 391 ng_generic_list_getLength(const struct ng_parse_type *type, 392 const u_char *start, const u_char *buf) 393 { 394 return *((const u_int32_t *)(buf - 4)); 395 } 396 397 /* Get length of the array of struct linkinfo inside a struct hooklist */ 398 static int 399 ng_generic_linkinfo_getLength(const struct ng_parse_type *type, 400 const u_char *start, const u_char *buf) 401 { 402 const struct hooklist *hl = (const struct hooklist *)start; 403 404 return hl->nodeinfo.hooks; 405 } 406 407 /* Array type for a variable length array of struct namelist */ 408 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = { 409 &ng_generic_nodeinfo_type, 410 &ng_generic_list_getLength 411 }; 412 static const struct ng_parse_type ng_generic_nodeinfoarray_type = { 413 &ng_parse_array_type, 414 &ng_nodeinfoarray_type_info 415 }; 416 417 /* Array type for a variable length array of struct typelist */ 418 static const struct ng_parse_array_info ng_typeinfoarray_type_info = { 419 &ng_generic_typeinfo_type, 420 &ng_generic_list_getLength 421 }; 422 static const struct ng_parse_type ng_generic_typeinfoarray_type = { 423 &ng_parse_array_type, 424 &ng_typeinfoarray_type_info 425 }; 426 427 /* Array type for array of struct linkinfo in struct hooklist */ 428 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = { 429 &ng_generic_linkinfo_type, 430 &ng_generic_linkinfo_getLength 431 }; 432 static const struct ng_parse_type ng_generic_linkinfo_array_type = { 433 &ng_parse_array_type, 434 &ng_generic_linkinfo_array_type_info 435 }; 436 437 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type)); 438 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST, 439 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type)); 440 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES, 441 (&ng_generic_nodeinfoarray_type)); 442 443 /* List of commands and how to convert arguments to/from ASCII */ 444 static const struct ng_cmdlist ng_generic_cmds[] = { 445 { 446 NGM_GENERIC_COOKIE, 447 NGM_SHUTDOWN, 448 "shutdown", 449 NULL, 450 NULL 451 }, 452 { 453 NGM_GENERIC_COOKIE, 454 NGM_MKPEER, 455 "mkpeer", 456 &ng_generic_mkpeer_type, 457 NULL 458 }, 459 { 460 NGM_GENERIC_COOKIE, 461 NGM_CONNECT, 462 "connect", 463 &ng_generic_connect_type, 464 NULL 465 }, 466 { 467 NGM_GENERIC_COOKIE, 468 NGM_NAME, 469 "name", 470 &ng_generic_name_type, 471 NULL 472 }, 473 { 474 NGM_GENERIC_COOKIE, 475 NGM_RMHOOK, 476 "rmhook", 477 &ng_generic_rmhook_type, 478 NULL 479 }, 480 { 481 NGM_GENERIC_COOKIE, 482 NGM_NODEINFO, 483 "nodeinfo", 484 NULL, 485 &ng_generic_nodeinfo_type 486 }, 487 { 488 NGM_GENERIC_COOKIE, 489 NGM_LISTHOOKS, 490 "listhooks", 491 NULL, 492 &ng_generic_hooklist_type 493 }, 494 { 495 NGM_GENERIC_COOKIE, 496 NGM_LISTNAMES, 497 "listnames", 498 NULL, 499 &ng_generic_listnodes_type /* same as NGM_LISTNODES */ 500 }, 501 { 502 NGM_GENERIC_COOKIE, 503 NGM_LISTNODES, 504 "listnodes", 505 NULL, 506 &ng_generic_listnodes_type 507 }, 508 { 509 NGM_GENERIC_COOKIE, 510 NGM_LISTTYPES, 511 "listtypes", 512 NULL, 513 &ng_generic_typeinfo_type 514 }, 515 { 516 NGM_GENERIC_COOKIE, 517 NGM_TEXT_CONFIG, 518 "textconfig", 519 NULL, 520 &ng_parse_string_type 521 }, 522 { 523 NGM_GENERIC_COOKIE, 524 NGM_TEXT_STATUS, 525 "textstatus", 526 NULL, 527 &ng_parse_string_type 528 }, 529 { 530 NGM_GENERIC_COOKIE, 531 NGM_ASCII2BINARY, 532 "ascii2binary", 533 &ng_parse_ng_mesg_type, 534 &ng_parse_ng_mesg_type 535 }, 536 { 537 NGM_GENERIC_COOKIE, 538 NGM_BINARY2ASCII, 539 "binary2ascii", 540 &ng_parse_ng_mesg_type, 541 &ng_parse_ng_mesg_type 542 }, 543 { 0 } 544 }; 545 546 /************************************************************************ 547 Node routines 548 ************************************************************************/ 549 550 /* 551 * Instantiate a node of the requested type 552 */ 553 int 554 ng_make_node(const char *typename, node_p *nodepp) 555 { 556 struct ng_type *type; 557 int error; 558 559 /* Check that the type makes sense */ 560 if (typename == NULL) { 561 TRAP_ERROR(); 562 return (EINVAL); 563 } 564 565 /* Locate the node type. If we fail we return. Do not try to load 566 * module. 567 */ 568 if ((type = ng_findtype(typename)) == NULL) 569 return (ENXIO); 570 571 /* 572 * If we have a constructor, then make the node and 573 * call the constructor to do type specific initialisation. 574 */ 575 if (type->constructor != NULL) { 576 if ((error = ng_make_node_common(type, nodepp)) == 0) { 577 if ((error = ((*type->constructor)(*nodepp)) != 0)) { 578 NG_NODE_UNREF(*nodepp); 579 } 580 } 581 } else { 582 /* 583 * Node has no constructor. We cannot ask for one 584 * to be made. It must be brought into existence by 585 * some external agency. The external agency should 586 * call ng_make_node_common() directly to get the 587 * netgraph part initialised. 588 */ 589 TRAP_ERROR(); 590 error = EINVAL; 591 } 592 return (error); 593 } 594 595 /* 596 * Generic node creation. Called by node initialisation for externally 597 * instantiated nodes (e.g. hardware, sockets, etc ). 598 * The returned node has a reference count of 1. 599 */ 600 int 601 ng_make_node_common(struct ng_type *type, node_p *nodepp) 602 { 603 node_p node; 604 605 /* Require the node type to have been already installed */ 606 if (ng_findtype(type->name) == NULL) { 607 TRAP_ERROR(); 608 return (EINVAL); 609 } 610 611 /* Make a node and try attach it to the type */ 612 NG_ALLOC_NODE(node); 613 if (node == NULL) { 614 TRAP_ERROR(); 615 return (ENOMEM); 616 } 617 node->nd_type = type; 618 NG_NODE_REF(node); /* note reference */ 619 type->refs++; 620 621 NG_QUEUE_LOCK_INIT(&node->nd_input_queue); 622 node->nd_input_queue.queue = NULL; 623 node->nd_input_queue.last = &node->nd_input_queue.queue; 624 node->nd_input_queue.q_flags = 0; 625 node->nd_input_queue.q_node = node; 626 627 /* Initialize hook list for new node */ 628 LIST_INIT(&node->nd_hooks); 629 630 /* Link us into the node linked list */ 631 mtx_lock(&ng_nodelist_mtx); 632 LIST_INSERT_HEAD(&ng_nodelist, node, nd_nodes); 633 mtx_unlock(&ng_nodelist_mtx); 634 635 636 /* get an ID and put us in the hash chain */ 637 mtx_lock(&ng_idhash_mtx); 638 for (;;) { /* wrap protection, even if silly */ 639 node_p node2 = NULL; 640 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */ 641 642 /* Is there a problem with the new number? */ 643 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */ 644 if ((node->nd_ID != 0) && (node2 == NULL)) { 645 break; 646 } 647 } 648 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)], 649 node, nd_idnodes); 650 mtx_unlock(&ng_idhash_mtx); 651 652 /* Done */ 653 *nodepp = node; 654 return (0); 655 } 656 657 /* 658 * Forceably start the shutdown process on a node. Either call 659 * its shutdown method, or do the default shutdown if there is 660 * no type-specific method. 661 * 662 * We can only be called from a shutdown message, so we know we have 663 * a writer lock, and therefore exclusive access. It also means 664 * that we should not be on the work queue, but we check anyhow. 665 * 666 * Persistent node types must have a type-specific method which 667 * allocates a new node in which case, this one is irretrievably going away, 668 * or cleans up anything it needs, and just makes the node valid again, 669 * in which case we allow the node to survive. 670 * 671 * XXX We need to think of how to tell a persistent node that we 672 * REALLY need to go away because the hardware has gone or we 673 * are rebooting.... etc. 674 */ 675 void 676 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3) 677 { 678 hook_p hook; 679 680 /* Check if it's already shutting down */ 681 if ((node->nd_flags & NGF_CLOSING) != 0) 682 return; 683 684 if (node == &ng_deadnode) { 685 printf ("shutdown called on deadnode\n"); 686 return; 687 } 688 689 /* Add an extra reference so it doesn't go away during this */ 690 NG_NODE_REF(node); 691 692 /* 693 * Mark it invalid so any newcomers know not to try use it 694 * Also add our own mark so we can't recurse 695 * note that NGF_INVALID does not do this as it's also set during 696 * creation 697 */ 698 node->nd_flags |= NGF_INVALID|NGF_CLOSING; 699 700 /* If node has its pre-shutdown method, then call it first*/ 701 if (node->nd_type && node->nd_type->close) 702 (*node->nd_type->close)(node); 703 704 /* Notify all remaining connected nodes to disconnect */ 705 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL) 706 ng_destroy_hook(hook); 707 708 /* 709 * Drain the input queue forceably. 710 * it has no hooks so what's it going to do, bleed on someone? 711 * Theoretically we came here from a queue entry that was added 712 * Just before the queue was closed, so it should be empty anyway. 713 * Also removes us from worklist if needed. 714 */ 715 ng_flush_input_queue(&node->nd_input_queue); 716 717 /* Ask the type if it has anything to do in this case */ 718 if (node->nd_type && node->nd_type->shutdown) { 719 (*node->nd_type->shutdown)(node); 720 if (NG_NODE_IS_VALID(node)) { 721 /* 722 * Well, blow me down if the node code hasn't declared 723 * that it doesn't want to die. 724 * Presumably it is a persistant node. 725 * If we REALLY want it to go away, 726 * e.g. hardware going away, 727 * Our caller should set NGF_REALLY_DIE in nd_flags. 728 */ 729 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING); 730 NG_NODE_UNREF(node); /* Assume they still have theirs */ 731 return; 732 } 733 } else { /* do the default thing */ 734 NG_NODE_UNREF(node); 735 } 736 737 ng_unname(node); /* basically a NOP these days */ 738 739 /* 740 * Remove extra reference, possibly the last 741 * Possible other holders of references may include 742 * timeout callouts, but theoretically the node's supposed to 743 * have cancelled them. Possibly hardware dependencies may 744 * force a driver to 'linger' with a reference. 745 */ 746 NG_NODE_UNREF(node); 747 } 748 749 /* 750 * Remove a reference to the node, possibly the last. 751 * deadnode always acts as it it were the last. 752 */ 753 int 754 ng_unref_node(node_p node) 755 { 756 int v; 757 758 if (node == &ng_deadnode) { 759 return (0); 760 } 761 762 do { 763 v = node->nd_refs - 1; 764 } while (! atomic_cmpset_int(&node->nd_refs, v + 1, v)); 765 766 if (v == 0) { /* we were the last */ 767 768 mtx_lock(&ng_nodelist_mtx); 769 node->nd_type->refs--; /* XXX maybe should get types lock? */ 770 LIST_REMOVE(node, nd_nodes); 771 mtx_unlock(&ng_nodelist_mtx); 772 773 mtx_lock(&ng_idhash_mtx); 774 LIST_REMOVE(node, nd_idnodes); 775 mtx_unlock(&ng_idhash_mtx); 776 777 mtx_destroy(&node->nd_input_queue.q_mtx); 778 NG_FREE_NODE(node); 779 } 780 return (v); 781 } 782 783 /************************************************************************ 784 Node ID handling 785 ************************************************************************/ 786 static node_p 787 ng_ID2noderef(ng_ID_t ID) 788 { 789 node_p node; 790 mtx_lock(&ng_idhash_mtx); 791 NG_IDHASH_FIND(ID, node); 792 if(node) 793 NG_NODE_REF(node); 794 mtx_unlock(&ng_idhash_mtx); 795 return(node); 796 } 797 798 ng_ID_t 799 ng_node2ID(node_p node) 800 { 801 return (node ? NG_NODE_ID(node) : 0); 802 } 803 804 /************************************************************************ 805 Node name handling 806 ************************************************************************/ 807 808 /* 809 * Assign a node a name. Once assigned, the name cannot be changed. 810 */ 811 int 812 ng_name_node(node_p node, const char *name) 813 { 814 int i; 815 node_p node2; 816 817 /* Check the name is valid */ 818 for (i = 0; i < NG_NODESIZ; i++) { 819 if (name[i] == '\0' || name[i] == '.' || name[i] == ':') 820 break; 821 } 822 if (i == 0 || name[i] != '\0') { 823 TRAP_ERROR(); 824 return (EINVAL); 825 } 826 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */ 827 TRAP_ERROR(); 828 return (EINVAL); 829 } 830 831 /* Check the name isn't already being used */ 832 if ((node2 = ng_name2noderef(node, name)) != NULL) { 833 NG_NODE_UNREF(node2); 834 TRAP_ERROR(); 835 return (EADDRINUSE); 836 } 837 838 /* copy it */ 839 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ); 840 841 return (0); 842 } 843 844 /* 845 * Find a node by absolute name. The name should NOT end with ':' 846 * The name "." means "this node" and "[xxx]" means "the node 847 * with ID (ie, at address) xxx". 848 * 849 * Returns the node if found, else NULL. 850 * Eventually should add something faster than a sequential search. 851 * Note it acquires a reference on the node so you can be sure it's still 852 * there. 853 */ 854 node_p 855 ng_name2noderef(node_p here, const char *name) 856 { 857 node_p node; 858 ng_ID_t temp; 859 860 /* "." means "this node" */ 861 if (strcmp(name, ".") == 0) { 862 NG_NODE_REF(here); 863 return(here); 864 } 865 866 /* Check for name-by-ID */ 867 if ((temp = ng_decodeidname(name)) != 0) { 868 return (ng_ID2noderef(temp)); 869 } 870 871 /* Find node by name */ 872 mtx_lock(&ng_nodelist_mtx); 873 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 874 if (NG_NODE_IS_VALID(node) 875 && NG_NODE_HAS_NAME(node) 876 && (strcmp(NG_NODE_NAME(node), name) == 0)) { 877 break; 878 } 879 } 880 if (node) 881 NG_NODE_REF(node); 882 mtx_unlock(&ng_nodelist_mtx); 883 return (node); 884 } 885 886 /* 887 * Decode an ID name, eg. "[f03034de]". Returns 0 if the 888 * string is not valid, otherwise returns the value. 889 */ 890 static ng_ID_t 891 ng_decodeidname(const char *name) 892 { 893 const int len = strlen(name); 894 char *eptr; 895 u_long val; 896 897 /* Check for proper length, brackets, no leading junk */ 898 if ((len < 3) 899 || (name[0] != '[') 900 || (name[len - 1] != ']') 901 || (!isxdigit(name[1]))) { 902 return ((ng_ID_t)0); 903 } 904 905 /* Decode number */ 906 val = strtoul(name + 1, &eptr, 16); 907 if ((eptr - name != len - 1) 908 || (val == ULONG_MAX) 909 || (val == 0)) { 910 return ((ng_ID_t)0); 911 } 912 return (ng_ID_t)val; 913 } 914 915 /* 916 * Remove a name from a node. This should only be called 917 * when shutting down and removing the node. 918 * IF we allow name changing this may be more resurrected. 919 */ 920 void 921 ng_unname(node_p node) 922 { 923 } 924 925 /************************************************************************ 926 Hook routines 927 Names are not optional. Hooks are always connected, except for a 928 brief moment within these routines. On invalidation or during creation 929 they are connected to the 'dead' hook. 930 ************************************************************************/ 931 932 /* 933 * Remove a hook reference 934 */ 935 void 936 ng_unref_hook(hook_p hook) 937 { 938 int v; 939 940 if (hook == &ng_deadhook) { 941 return; 942 } 943 do { 944 v = hook->hk_refs; 945 } while (! atomic_cmpset_int(&hook->hk_refs, v, v - 1)); 946 947 if (v == 1) { /* we were the last */ 948 if (_NG_HOOK_NODE(hook)) { /* it'll probably be ng_deadnode */ 949 _NG_NODE_UNREF((_NG_HOOK_NODE(hook))); 950 hook->hk_node = NULL; 951 } 952 NG_FREE_HOOK(hook); 953 } 954 } 955 956 /* 957 * Add an unconnected hook to a node. Only used internally. 958 * Assumes node is locked. (XXX not yet true ) 959 */ 960 static int 961 ng_add_hook(node_p node, const char *name, hook_p *hookp) 962 { 963 hook_p hook; 964 int error = 0; 965 966 /* Check that the given name is good */ 967 if (name == NULL) { 968 TRAP_ERROR(); 969 return (EINVAL); 970 } 971 if (ng_findhook(node, name) != NULL) { 972 TRAP_ERROR(); 973 return (EEXIST); 974 } 975 976 /* Allocate the hook and link it up */ 977 NG_ALLOC_HOOK(hook); 978 if (hook == NULL) { 979 TRAP_ERROR(); 980 return (ENOMEM); 981 } 982 hook->hk_refs = 1; /* add a reference for us to return */ 983 hook->hk_flags = HK_INVALID; 984 hook->hk_peer = &ng_deadhook; /* start off this way */ 985 hook->hk_node = node; 986 NG_NODE_REF(node); /* each hook counts as a reference */ 987 988 /* Set hook name */ 989 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ); 990 991 /* 992 * Check if the node type code has something to say about it 993 * If it fails, the unref of the hook will also unref the node. 994 */ 995 if (node->nd_type->newhook != NULL) { 996 if ((error = (*node->nd_type->newhook)(node, hook, name))) { 997 NG_HOOK_UNREF(hook); /* this frees the hook */ 998 return (error); 999 } 1000 } 1001 /* 1002 * The 'type' agrees so far, so go ahead and link it in. 1003 * We'll ask again later when we actually connect the hooks. 1004 */ 1005 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1006 node->nd_numhooks++; 1007 NG_HOOK_REF(hook); /* one for the node */ 1008 1009 if (hookp) 1010 *hookp = hook; 1011 return (0); 1012 } 1013 1014 /* 1015 * Find a hook 1016 * 1017 * Node types may supply their own optimized routines for finding 1018 * hooks. If none is supplied, we just do a linear search. 1019 * XXX Possibly we should add a reference to the hook? 1020 */ 1021 hook_p 1022 ng_findhook(node_p node, const char *name) 1023 { 1024 hook_p hook; 1025 1026 if (node->nd_type->findhook != NULL) 1027 return (*node->nd_type->findhook)(node, name); 1028 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) { 1029 if (NG_HOOK_IS_VALID(hook) 1030 && (strcmp(NG_HOOK_NAME(hook), name) == 0)) 1031 return (hook); 1032 } 1033 return (NULL); 1034 } 1035 1036 /* 1037 * Destroy a hook 1038 * 1039 * As hooks are always attached, this really destroys two hooks. 1040 * The one given, and the one attached to it. Disconnect the hooks 1041 * from each other first. We reconnect the peer hook to the 'dead' 1042 * hook so that it can still exist after we depart. We then 1043 * send the peer its own destroy message. This ensures that we only 1044 * interact with the peer's structures when it is locked processing that 1045 * message. We hold a reference to the peer hook so we are guaranteed that 1046 * the peer hook and node are still going to exist until 1047 * we are finished there as the hook holds a ref on the node. 1048 * We run this same code again on the peer hook, but that time it is already 1049 * attached to the 'dead' hook. 1050 * 1051 * This routine is called at all stages of hook creation 1052 * on error detection and must be able to handle any such stage. 1053 */ 1054 void 1055 ng_destroy_hook(hook_p hook) 1056 { 1057 hook_p peer; 1058 node_p node; 1059 1060 if (hook == &ng_deadhook) { /* better safe than sorry */ 1061 printf("ng_destroy_hook called on deadhook\n"); 1062 return; 1063 } 1064 1065 /* 1066 * Protect divorce process with mutex, to avoid races on 1067 * simultaneous disconnect. 1068 */ 1069 mtx_lock(&ng_topo_mtx); 1070 1071 hook->hk_flags |= HK_INVALID; 1072 1073 peer = NG_HOOK_PEER(hook); 1074 node = NG_HOOK_NODE(hook); 1075 1076 if (peer && (peer != &ng_deadhook)) { 1077 /* 1078 * Set the peer to point to ng_deadhook 1079 * from this moment on we are effectively independent it. 1080 * send it an rmhook message of it's own. 1081 */ 1082 peer->hk_peer = &ng_deadhook; /* They no longer know us */ 1083 hook->hk_peer = &ng_deadhook; /* Nor us, them */ 1084 if (NG_HOOK_NODE(peer) == &ng_deadnode) { 1085 /* 1086 * If it's already divorced from a node, 1087 * just free it. 1088 */ 1089 mtx_unlock(&ng_topo_mtx); 1090 } else { 1091 mtx_unlock(&ng_topo_mtx); 1092 ng_rmhook_self(peer); /* Send it a surprise */ 1093 } 1094 NG_HOOK_UNREF(peer); /* account for peer link */ 1095 NG_HOOK_UNREF(hook); /* account for peer link */ 1096 } else 1097 mtx_unlock(&ng_topo_mtx); 1098 1099 mtx_assert(&ng_topo_mtx, MA_NOTOWNED); 1100 1101 /* 1102 * Remove the hook from the node's list to avoid possible recursion 1103 * in case the disconnection results in node shutdown. 1104 */ 1105 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */ 1106 return; 1107 } 1108 LIST_REMOVE(hook, hk_hooks); 1109 node->nd_numhooks--; 1110 if (node->nd_type->disconnect) { 1111 /* 1112 * The type handler may elect to destroy the node so don't 1113 * trust its existence after this point. (except 1114 * that we still hold a reference on it. (which we 1115 * inherrited from the hook we are destroying) 1116 */ 1117 (*node->nd_type->disconnect) (hook); 1118 } 1119 1120 /* 1121 * Note that because we will point to ng_deadnode, the original node 1122 * is not decremented automatically so we do that manually. 1123 */ 1124 _NG_HOOK_NODE(hook) = &ng_deadnode; 1125 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */ 1126 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */ 1127 } 1128 1129 /* 1130 * Take two hooks on a node and merge the connection so that the given node 1131 * is effectively bypassed. 1132 */ 1133 int 1134 ng_bypass(hook_p hook1, hook_p hook2) 1135 { 1136 if (hook1->hk_node != hook2->hk_node) { 1137 TRAP_ERROR(); 1138 return (EINVAL); 1139 } 1140 hook1->hk_peer->hk_peer = hook2->hk_peer; 1141 hook2->hk_peer->hk_peer = hook1->hk_peer; 1142 1143 hook1->hk_peer = &ng_deadhook; 1144 hook2->hk_peer = &ng_deadhook; 1145 1146 NG_HOOK_UNREF(hook1); 1147 NG_HOOK_UNREF(hook2); 1148 1149 /* XXX If we ever cache methods on hooks update them as well */ 1150 ng_destroy_hook(hook1); 1151 ng_destroy_hook(hook2); 1152 return (0); 1153 } 1154 1155 /* 1156 * Install a new netgraph type 1157 */ 1158 int 1159 ng_newtype(struct ng_type *tp) 1160 { 1161 const size_t namelen = strlen(tp->name); 1162 1163 /* Check version and type name fields */ 1164 if ((tp->version != NG_ABI_VERSION) 1165 || (namelen == 0) 1166 || (namelen >= NG_TYPESIZ)) { 1167 TRAP_ERROR(); 1168 if (tp->version != NG_ABI_VERSION) { 1169 printf("Netgraph: Node type rejected. ABI mismatch. Suggest recompile\n"); 1170 } 1171 return (EINVAL); 1172 } 1173 1174 /* Check for name collision */ 1175 if (ng_findtype(tp->name) != NULL) { 1176 TRAP_ERROR(); 1177 return (EEXIST); 1178 } 1179 1180 1181 /* Link in new type */ 1182 mtx_lock(&ng_typelist_mtx); 1183 LIST_INSERT_HEAD(&ng_typelist, tp, types); 1184 tp->refs = 1; /* first ref is linked list */ 1185 mtx_unlock(&ng_typelist_mtx); 1186 return (0); 1187 } 1188 1189 /* 1190 * unlink a netgraph type 1191 * If no examples exist 1192 */ 1193 int 1194 ng_rmtype(struct ng_type *tp) 1195 { 1196 /* Check for name collision */ 1197 if (tp->refs != 1) { 1198 TRAP_ERROR(); 1199 return (EBUSY); 1200 } 1201 1202 /* Unlink type */ 1203 mtx_lock(&ng_typelist_mtx); 1204 LIST_REMOVE(tp, types); 1205 mtx_unlock(&ng_typelist_mtx); 1206 return (0); 1207 } 1208 1209 /* 1210 * Look for a type of the name given 1211 */ 1212 struct ng_type * 1213 ng_findtype(const char *typename) 1214 { 1215 struct ng_type *type; 1216 1217 mtx_lock(&ng_typelist_mtx); 1218 LIST_FOREACH(type, &ng_typelist, types) { 1219 if (strcmp(type->name, typename) == 0) 1220 break; 1221 } 1222 mtx_unlock(&ng_typelist_mtx); 1223 return (type); 1224 } 1225 1226 /************************************************************************ 1227 Composite routines 1228 ************************************************************************/ 1229 /* 1230 * Connect two nodes using the specified hooks, using queued functions. 1231 */ 1232 static void 1233 ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2) 1234 { 1235 1236 /* 1237 * When we run, we know that the node 'node' is locked for us. 1238 * Our caller has a reference on the hook. 1239 * Our caller has a reference on the node. 1240 * (In this case our caller is ng_apply_item() ). 1241 * The peer hook has a reference on the hook. 1242 * We are all set up except for the final call to the node, and 1243 * the clearing of the INVALID flag. 1244 */ 1245 if (NG_HOOK_NODE(hook) == &ng_deadnode) { 1246 /* 1247 * The node must have been freed again since we last visited 1248 * here. ng_destry_hook() has this effect but nothing else does. 1249 * We should just release our references and 1250 * free anything we can think of. 1251 * Since we know it's been destroyed, and it's our caller 1252 * that holds the references, just return. 1253 */ 1254 return ; 1255 } 1256 if (hook->hk_node->nd_type->connect) { 1257 if ((*hook->hk_node->nd_type->connect) (hook)) { 1258 ng_destroy_hook(hook); /* also zaps peer */ 1259 printf("failed in ng_con_part3()\n"); 1260 return ; 1261 } 1262 } 1263 /* 1264 * XXX this is wrong for SMP. Possibly we need 1265 * to separate out 'create' and 'invalid' flags. 1266 * should only set flags on hooks we have locked under our node. 1267 */ 1268 hook->hk_flags &= ~HK_INVALID; 1269 return ; 1270 } 1271 1272 static void 1273 ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2) 1274 { 1275 hook_p peer; 1276 1277 /* 1278 * When we run, we know that the node 'node' is locked for us. 1279 * Our caller has a reference on the hook. 1280 * Our caller has a reference on the node. 1281 * (In this case our caller is ng_apply_item() ). 1282 * The peer hook has a reference on the hook. 1283 * our node pointer points to the 'dead' node. 1284 * First check the hook name is unique. 1285 * Should not happen because we checked before queueing this. 1286 */ 1287 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) { 1288 TRAP_ERROR(); 1289 ng_destroy_hook(hook); /* should destroy peer too */ 1290 printf("failed in ng_con_part2()\n"); 1291 return ; 1292 } 1293 /* 1294 * Check if the node type code has something to say about it 1295 * If it fails, the unref of the hook will also unref the attached node, 1296 * however since that node is 'ng_deadnode' this will do nothing. 1297 * The peer hook will also be destroyed. 1298 */ 1299 if (node->nd_type->newhook != NULL) { 1300 if ((*node->nd_type->newhook)(node, hook, hook->hk_name)) { 1301 ng_destroy_hook(hook); /* should destroy peer too */ 1302 printf("failed in ng_con_part2()\n"); 1303 return ; 1304 } 1305 } 1306 1307 /* 1308 * The 'type' agrees so far, so go ahead and link it in. 1309 * We'll ask again later when we actually connect the hooks. 1310 */ 1311 hook->hk_node = node; /* just overwrite ng_deadnode */ 1312 NG_NODE_REF(node); /* each hook counts as a reference */ 1313 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1314 node->nd_numhooks++; 1315 NG_HOOK_REF(hook); /* one for the node */ 1316 1317 /* 1318 * We now have a symmetrical situation, where both hooks have been 1319 * linked to their nodes, the newhook methods have been called 1320 * And the references are all correct. The hooks are still marked 1321 * as invalid, as we have not called the 'connect' methods 1322 * yet. 1323 * We can call the local one immediately as we have the 1324 * node locked, but we need to queue the remote one. 1325 */ 1326 if (hook->hk_node->nd_type->connect) { 1327 if ((*hook->hk_node->nd_type->connect) (hook)) { 1328 ng_destroy_hook(hook); /* also zaps peer */ 1329 printf("failed in ng_con_part2(A)\n"); 1330 return ; 1331 } 1332 } 1333 1334 /* 1335 * Acquire topo mutex to avoid race with ng_destroy_hook(). 1336 */ 1337 mtx_lock(&ng_topo_mtx); 1338 peer = hook->hk_peer; 1339 if (peer == &ng_deadhook) { 1340 mtx_unlock(&ng_topo_mtx); 1341 printf("failed in ng_con_part2(B)\n"); 1342 ng_destroy_hook(hook); 1343 return ; 1344 } 1345 mtx_unlock(&ng_topo_mtx); 1346 1347 if (ng_send_fn(peer->hk_node, peer, &ng_con_part3, arg1, arg2)) { 1348 printf("failed in ng_con_part2(C)\n"); 1349 ng_destroy_hook(hook); /* also zaps peer */ 1350 return ; 1351 } 1352 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */ 1353 return ; 1354 } 1355 1356 /* 1357 * Connect this node with another node. We assume that this node is 1358 * currently locked, as we are only called from an NGM_CONNECT message. 1359 */ 1360 static int 1361 ng_con_nodes(node_p node, const char *name, node_p node2, const char *name2) 1362 { 1363 int error; 1364 hook_p hook; 1365 hook_p hook2; 1366 1367 if (ng_findhook(node2, name2) != NULL) { 1368 return(EEXIST); 1369 } 1370 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */ 1371 return (error); 1372 /* Allocate the other hook and link it up */ 1373 NG_ALLOC_HOOK(hook2); 1374 if (hook2 == NULL) { 1375 TRAP_ERROR(); 1376 ng_destroy_hook(hook); /* XXX check ref counts so far */ 1377 NG_HOOK_UNREF(hook); /* including our ref */ 1378 return (ENOMEM); 1379 } 1380 hook2->hk_refs = 1; /* start with a reference for us. */ 1381 hook2->hk_flags = HK_INVALID; 1382 hook2->hk_peer = hook; /* Link the two together */ 1383 hook->hk_peer = hook2; 1384 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/ 1385 NG_HOOK_REF(hook2); 1386 hook2->hk_node = &ng_deadnode; 1387 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ); 1388 1389 /* 1390 * Queue the function above. 1391 * Procesing continues in that function in the lock context of 1392 * the other node. 1393 */ 1394 ng_send_fn(node2, hook2, &ng_con_part2, NULL, 0); 1395 1396 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */ 1397 NG_HOOK_UNREF(hook2); 1398 return (0); 1399 } 1400 1401 /* 1402 * Make a peer and connect. 1403 * We assume that the local node is locked. 1404 * The new node probably doesn't need a lock until 1405 * it has a hook, because it cannot really have any work until then, 1406 * but we should think about it a bit more. 1407 * 1408 * The problem may come if the other node also fires up 1409 * some hardware or a timer or some other source of activation, 1410 * also it may already get a command msg via it's ID. 1411 * 1412 * We could use the same method as ng_con_nodes() but we'd have 1413 * to add ability to remove the node when failing. (Not hard, just 1414 * make arg1 point to the node to remove). 1415 * Unless of course we just ignore failure to connect and leave 1416 * an unconnected node? 1417 */ 1418 static int 1419 ng_mkpeer(node_p node, const char *name, const char *name2, char *type) 1420 { 1421 node_p node2; 1422 hook_p hook1, hook2; 1423 int error; 1424 1425 if ((error = ng_make_node(type, &node2))) { 1426 return (error); 1427 } 1428 1429 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */ 1430 ng_rmnode(node2, NULL, NULL, 0); 1431 return (error); 1432 } 1433 1434 if ((error = ng_add_hook(node2, name2, &hook2))) { 1435 ng_rmnode(node2, NULL, NULL, 0); 1436 ng_destroy_hook(hook1); 1437 NG_HOOK_UNREF(hook1); 1438 return (error); 1439 } 1440 1441 /* 1442 * Actually link the two hooks together. 1443 */ 1444 hook1->hk_peer = hook2; 1445 hook2->hk_peer = hook1; 1446 1447 /* Each hook is referenced by the other */ 1448 NG_HOOK_REF(hook1); 1449 NG_HOOK_REF(hook2); 1450 1451 /* Give each node the opportunity to veto the pending connection */ 1452 if (hook1->hk_node->nd_type->connect) { 1453 error = (*hook1->hk_node->nd_type->connect) (hook1); 1454 } 1455 1456 if ((error == 0) && hook2->hk_node->nd_type->connect) { 1457 error = (*hook2->hk_node->nd_type->connect) (hook2); 1458 1459 } 1460 1461 /* 1462 * drop the references we were holding on the two hooks. 1463 */ 1464 if (error) { 1465 ng_destroy_hook(hook2); /* also zaps hook1 */ 1466 ng_rmnode(node2, NULL, NULL, 0); 1467 } else { 1468 /* As a last act, allow the hooks to be used */ 1469 hook1->hk_flags &= ~HK_INVALID; 1470 hook2->hk_flags &= ~HK_INVALID; 1471 } 1472 NG_HOOK_UNREF(hook1); 1473 NG_HOOK_UNREF(hook2); 1474 return (error); 1475 } 1476 1477 /************************************************************************ 1478 Utility routines to send self messages 1479 ************************************************************************/ 1480 1481 /* Shut this node down as soon as everyone is clear of it */ 1482 /* Should add arg "immediately" to jump the queue */ 1483 int 1484 ng_rmnode_self(node_p node) 1485 { 1486 int error; 1487 1488 if (node == &ng_deadnode) 1489 return (0); 1490 node->nd_flags |= NGF_INVALID; 1491 if (node->nd_flags & NGF_CLOSING) 1492 return (0); 1493 1494 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0); 1495 return (error); 1496 } 1497 1498 static void 1499 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2) 1500 { 1501 ng_destroy_hook(hook); 1502 return ; 1503 } 1504 1505 int 1506 ng_rmhook_self(hook_p hook) 1507 { 1508 int error; 1509 node_p node = NG_HOOK_NODE(hook); 1510 1511 if (node == &ng_deadnode) 1512 return (0); 1513 1514 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0); 1515 return (error); 1516 } 1517 1518 /*********************************************************************** 1519 * Parse and verify a string of the form: <NODE:><PATH> 1520 * 1521 * Such a string can refer to a specific node or a specific hook 1522 * on a specific node, depending on how you look at it. In the 1523 * latter case, the PATH component must not end in a dot. 1524 * 1525 * Both <NODE:> and <PATH> are optional. The <PATH> is a string 1526 * of hook names separated by dots. This breaks out the original 1527 * string, setting *nodep to "NODE" (or NULL if none) and *pathp 1528 * to "PATH" (or NULL if degenerate). Also, *hookp will point to 1529 * the final hook component of <PATH>, if any, otherwise NULL. 1530 * 1531 * This returns -1 if the path is malformed. The char ** are optional. 1532 ***********************************************************************/ 1533 int 1534 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp) 1535 { 1536 char *node, *path, *hook; 1537 int k; 1538 1539 /* 1540 * Extract absolute NODE, if any 1541 */ 1542 for (path = addr; *path && *path != ':'; path++); 1543 if (*path) { 1544 node = addr; /* Here's the NODE */ 1545 *path++ = '\0'; /* Here's the PATH */ 1546 1547 /* Node name must not be empty */ 1548 if (!*node) 1549 return -1; 1550 1551 /* A name of "." is OK; otherwise '.' not allowed */ 1552 if (strcmp(node, ".") != 0) { 1553 for (k = 0; node[k]; k++) 1554 if (node[k] == '.') 1555 return -1; 1556 } 1557 } else { 1558 node = NULL; /* No absolute NODE */ 1559 path = addr; /* Here's the PATH */ 1560 } 1561 1562 /* Snoop for illegal characters in PATH */ 1563 for (k = 0; path[k]; k++) 1564 if (path[k] == ':') 1565 return -1; 1566 1567 /* Check for no repeated dots in PATH */ 1568 for (k = 0; path[k]; k++) 1569 if (path[k] == '.' && path[k + 1] == '.') 1570 return -1; 1571 1572 /* Remove extra (degenerate) dots from beginning or end of PATH */ 1573 if (path[0] == '.') 1574 path++; 1575 if (*path && path[strlen(path) - 1] == '.') 1576 path[strlen(path) - 1] = 0; 1577 1578 /* If PATH has a dot, then we're not talking about a hook */ 1579 if (*path) { 1580 for (hook = path, k = 0; path[k]; k++) 1581 if (path[k] == '.') { 1582 hook = NULL; 1583 break; 1584 } 1585 } else 1586 path = hook = NULL; 1587 1588 /* Done */ 1589 if (nodep) 1590 *nodep = node; 1591 if (pathp) 1592 *pathp = path; 1593 if (hookp) 1594 *hookp = hook; 1595 return (0); 1596 } 1597 1598 /* 1599 * Given a path, which may be absolute or relative, and a starting node, 1600 * return the destination node. 1601 */ 1602 int 1603 ng_path2noderef(node_p here, const char *address, 1604 node_p *destp, hook_p *lasthook) 1605 { 1606 char fullpath[NG_PATHSIZ]; 1607 char *nodename, *path, pbuf[2]; 1608 node_p node, oldnode; 1609 char *cp; 1610 hook_p hook = NULL; 1611 1612 /* Initialize */ 1613 if (destp == NULL) { 1614 TRAP_ERROR(); 1615 return EINVAL; 1616 } 1617 *destp = NULL; 1618 1619 /* Make a writable copy of address for ng_path_parse() */ 1620 strncpy(fullpath, address, sizeof(fullpath) - 1); 1621 fullpath[sizeof(fullpath) - 1] = '\0'; 1622 1623 /* Parse out node and sequence of hooks */ 1624 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) { 1625 TRAP_ERROR(); 1626 return EINVAL; 1627 } 1628 if (path == NULL) { 1629 pbuf[0] = '.'; /* Needs to be writable */ 1630 pbuf[1] = '\0'; 1631 path = pbuf; 1632 } 1633 1634 /* 1635 * For an absolute address, jump to the starting node. 1636 * Note that this holds a reference on the node for us. 1637 * Don't forget to drop the reference if we don't need it. 1638 */ 1639 if (nodename) { 1640 node = ng_name2noderef(here, nodename); 1641 if (node == NULL) { 1642 TRAP_ERROR(); 1643 return (ENOENT); 1644 } 1645 } else { 1646 if (here == NULL) { 1647 TRAP_ERROR(); 1648 return (EINVAL); 1649 } 1650 node = here; 1651 NG_NODE_REF(node); 1652 } 1653 1654 /* 1655 * Now follow the sequence of hooks 1656 * XXX 1657 * We actually cannot guarantee that the sequence 1658 * is not being demolished as we crawl along it 1659 * without extra-ordinary locking etc. 1660 * So this is a bit dodgy to say the least. 1661 * We can probably hold up some things by holding 1662 * the nodelist mutex for the time of this 1663 * crawl if we wanted.. At least that way we wouldn't have to 1664 * worry about the nodes disappearing, but the hooks would still 1665 * be a problem. 1666 */ 1667 for (cp = path; node != NULL && *cp != '\0'; ) { 1668 char *segment; 1669 1670 /* 1671 * Break out the next path segment. Replace the dot we just 1672 * found with a NUL; "cp" points to the next segment (or the 1673 * NUL at the end). 1674 */ 1675 for (segment = cp; *cp != '\0'; cp++) { 1676 if (*cp == '.') { 1677 *cp++ = '\0'; 1678 break; 1679 } 1680 } 1681 1682 /* Empty segment */ 1683 if (*segment == '\0') 1684 continue; 1685 1686 /* We have a segment, so look for a hook by that name */ 1687 hook = ng_findhook(node, segment); 1688 1689 /* Can't get there from here... */ 1690 if (hook == NULL 1691 || NG_HOOK_PEER(hook) == NULL 1692 || NG_HOOK_NOT_VALID(hook) 1693 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) { 1694 TRAP_ERROR(); 1695 NG_NODE_UNREF(node); 1696 #if 0 1697 printf("hooknotvalid %s %s %d %d %d %d ", 1698 path, 1699 segment, 1700 hook == NULL, 1701 NG_HOOK_PEER(hook) == NULL, 1702 NG_HOOK_NOT_VALID(hook), 1703 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))); 1704 #endif 1705 return (ENOENT); 1706 } 1707 1708 /* 1709 * Hop on over to the next node 1710 * XXX 1711 * Big race conditions here as hooks and nodes go away 1712 * *** Idea.. store an ng_ID_t in each hook and use that 1713 * instead of the direct hook in this crawl? 1714 */ 1715 oldnode = node; 1716 if ((node = NG_PEER_NODE(hook))) 1717 NG_NODE_REF(node); /* XXX RACE */ 1718 NG_NODE_UNREF(oldnode); /* XXX another race */ 1719 if (NG_NODE_NOT_VALID(node)) { 1720 NG_NODE_UNREF(node); /* XXX more races */ 1721 node = NULL; 1722 } 1723 } 1724 1725 /* If node somehow missing, fail here (probably this is not needed) */ 1726 if (node == NULL) { 1727 TRAP_ERROR(); 1728 return (ENXIO); 1729 } 1730 1731 /* Done */ 1732 *destp = node; 1733 if (lasthook != NULL) 1734 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL); 1735 return (0); 1736 } 1737 1738 /***************************************************************\ 1739 * Input queue handling. 1740 * All activities are submitted to the node via the input queue 1741 * which implements a multiple-reader/single-writer gate. 1742 * Items which cannot be handled immediately are queued. 1743 * 1744 * read-write queue locking inline functions * 1745 \***************************************************************/ 1746 1747 static __inline item_p ng_dequeue(struct ng_queue * ngq, int *rw); 1748 static __inline item_p ng_acquire_read(struct ng_queue * ngq, 1749 item_p item); 1750 static __inline item_p ng_acquire_write(struct ng_queue * ngq, 1751 item_p item); 1752 static __inline void ng_leave_read(struct ng_queue * ngq); 1753 static __inline void ng_leave_write(struct ng_queue * ngq); 1754 static __inline void ng_queue_rw(struct ng_queue * ngq, 1755 item_p item, int rw); 1756 1757 /* 1758 * Definition of the bits fields in the ng_queue flag word. 1759 * Defined here rather than in netgraph.h because no-one should fiddle 1760 * with them. 1761 * 1762 * The ordering here may be important! don't shuffle these. 1763 */ 1764 /*- 1765 Safety Barrier--------+ (adjustable to suit taste) (not used yet) 1766 | 1767 V 1768 +-------+-------+-------+-------+-------+-------+-------+-------+ 1769 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1770 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |P|A| 1771 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |O|W| 1772 +-------+-------+-------+-------+-------+-------+-------+-------+ 1773 \___________________________ ____________________________/ | | 1774 V | | 1775 [active reader count] | | 1776 | | 1777 Operation Pending -------------------------------+ | 1778 | 1779 Active Writer ---------------------------------------+ 1780 1781 1782 */ 1783 #define WRITER_ACTIVE 0x00000001 1784 #define OP_PENDING 0x00000002 1785 #define READER_INCREMENT 0x00000004 1786 #define READER_MASK 0xfffffffc /* Not valid if WRITER_ACTIVE is set */ 1787 #define SAFETY_BARRIER 0x00100000 /* 128K items queued should be enough */ 1788 1789 /* Defines of more elaborate states on the queue */ 1790 /* Mask of bits a new read cares about */ 1791 #define NGQ_RMASK (WRITER_ACTIVE|OP_PENDING) 1792 1793 /* Mask of bits a new write cares about */ 1794 #define NGQ_WMASK (NGQ_RMASK|READER_MASK) 1795 1796 /* Test to decide if there is something on the queue. */ 1797 #define QUEUE_ACTIVE(QP) ((QP)->q_flags & OP_PENDING) 1798 1799 /* How to decide what the next queued item is. */ 1800 #define HEAD_IS_READER(QP) NGI_QUEUED_READER((QP)->queue) 1801 #define HEAD_IS_WRITER(QP) NGI_QUEUED_WRITER((QP)->queue) /* notused */ 1802 1803 /* Read the status to decide if the next item on the queue can now run. */ 1804 #define QUEUED_READER_CAN_PROCEED(QP) \ 1805 (((QP)->q_flags & (NGQ_RMASK & ~OP_PENDING)) == 0) 1806 #define QUEUED_WRITER_CAN_PROCEED(QP) \ 1807 (((QP)->q_flags & (NGQ_WMASK & ~OP_PENDING)) == 0) 1808 1809 /* Is there a chance of getting ANY work off the queue? */ 1810 #define NEXT_QUEUED_ITEM_CAN_PROCEED(QP) \ 1811 (QUEUE_ACTIVE(QP) && \ 1812 ((HEAD_IS_READER(QP)) ? QUEUED_READER_CAN_PROCEED(QP) : \ 1813 QUEUED_WRITER_CAN_PROCEED(QP))) 1814 1815 1816 #define NGQRW_R 0 1817 #define NGQRW_W 1 1818 1819 /* 1820 * Taking into account the current state of the queue and node, possibly take 1821 * the next entry off the queue and return it. Return NULL if there was 1822 * nothing we could return, either because there really was nothing there, or 1823 * because the node was in a state where it cannot yet process the next item 1824 * on the queue. 1825 * 1826 * This MUST MUST MUST be called with the mutex held. 1827 */ 1828 static __inline item_p 1829 ng_dequeue(struct ng_queue *ngq, int *rw) 1830 { 1831 item_p item; 1832 u_int add_arg; 1833 1834 mtx_assert(&ngq->q_mtx, MA_OWNED); 1835 /* 1836 * If there is nothing queued, then just return. 1837 * No point in continuing. 1838 * XXXGL: assert this? 1839 */ 1840 if (!QUEUE_ACTIVE(ngq)) { 1841 CTR4(KTR_NET, "%20s: node [%x] (%p) queue empty; " 1842 "queue flags 0x%lx", __func__, 1843 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1844 return (NULL); 1845 } 1846 1847 /* 1848 * From here, we can assume there is a head item. 1849 * We need to find out what it is and if it can be dequeued, given 1850 * the current state of the node. 1851 */ 1852 if (HEAD_IS_READER(ngq)) { 1853 if (!QUEUED_READER_CAN_PROCEED(ngq)) { 1854 /* 1855 * It's a reader but we can't use it. 1856 * We are stalled so make sure we don't 1857 * get called again until something changes. 1858 */ 1859 ng_worklist_remove(ngq->q_node); 1860 CTR4(KTR_NET, "%20s: node [%x] (%p) queued reader " 1861 "can't proceed; queue flags 0x%lx", __func__, 1862 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1863 return (NULL); 1864 } 1865 /* 1866 * Head of queue is a reader and we have no write active. 1867 * We don't care how many readers are already active. 1868 * Add the correct increment for the reader count. 1869 */ 1870 add_arg = READER_INCREMENT; 1871 *rw = NGQRW_R; 1872 } else if (QUEUED_WRITER_CAN_PROCEED(ngq)) { 1873 /* 1874 * There is a pending write, no readers and no active writer. 1875 * This means we can go ahead with the pending writer. Note 1876 * the fact that we now have a writer, ready for when we take 1877 * it off the queue. 1878 * 1879 * We don't need to worry about a possible collision with the 1880 * fasttrack reader. 1881 * 1882 * The fasttrack thread may take a long time to discover that we 1883 * are running so we would have an inconsistent state in the 1884 * flags for a while. Since we ignore the reader count 1885 * entirely when the WRITER_ACTIVE flag is set, this should 1886 * not matter (in fact it is defined that way). If it tests 1887 * the flag before this operation, the OP_PENDING flag 1888 * will make it fail, and if it tests it later, the 1889 * WRITER_ACTIVE flag will do the same. If it is SO slow that 1890 * we have actually completed the operation, and neither flag 1891 * is set by the time that it tests the flags, then it is 1892 * actually ok for it to continue. If it completes and we've 1893 * finished and the read pending is set it still fails. 1894 * 1895 * So we can just ignore it, as long as we can ensure that the 1896 * transition from WRITE_PENDING state to the WRITER_ACTIVE 1897 * state is atomic. 1898 * 1899 * After failing, first it will be held back by the mutex, then 1900 * when it can proceed, it will queue its request, then it 1901 * would arrive at this function. Usually it will have to 1902 * leave empty handed because the ACTIVE WRITER bit will be 1903 * set. 1904 * 1905 * Adjust the flags for the new active writer. 1906 */ 1907 add_arg = WRITER_ACTIVE; 1908 *rw = NGQRW_W; 1909 /* 1910 * We want to write "active writer, no readers " Now go make 1911 * it true. In fact there may be a number in the readers 1912 * count but we know it is not true and will be fixed soon. 1913 * We will fix the flags for the next pending entry in a 1914 * moment. 1915 */ 1916 } else { 1917 /* 1918 * We can't dequeue anything.. return and say so. Probably we 1919 * have a write pending and the readers count is non zero. If 1920 * we got here because a reader hit us just at the wrong 1921 * moment with the fasttrack code, and put us in a strange 1922 * state, then it will be coming through in just a moment, 1923 * (just as soon as we release the mutex) and keep things 1924 * moving. 1925 * Make sure we remove ourselves from the work queue. It 1926 * would be a waste of effort to do all this again. 1927 */ 1928 ng_worklist_remove(ngq->q_node); 1929 CTR4(KTR_NET, "%20s: node [%x] (%p) can't dequeue anything; " 1930 "queue flags 0x%lx", __func__, 1931 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1932 return (NULL); 1933 } 1934 1935 /* 1936 * Now we dequeue the request (whatever it may be) and correct the 1937 * pending flags and the next and last pointers. 1938 */ 1939 item = ngq->queue; 1940 ngq->queue = item->el_next; 1941 CTR6(KTR_NET, "%20s: node [%x] (%p) dequeued item %p with flags 0x%lx; " 1942 "queue flags 0x%lx", __func__, 1943 ngq->q_node->nd_ID,ngq->q_node, item, item->el_flags, ngq->q_flags); 1944 if (ngq->last == &(item->el_next)) { 1945 /* 1946 * that was the last entry in the queue so set the 'last 1947 * pointer up correctly and make sure the pending flag is 1948 * clear. 1949 */ 1950 add_arg += -OP_PENDING; 1951 ngq->last = &(ngq->queue); 1952 /* 1953 * Whatever flag was set will be cleared and 1954 * the new acive field will be set by the add as well, 1955 * so we don't need to change add_arg. 1956 * But we know we don't need to be on the work list. 1957 */ 1958 atomic_add_long(&ngq->q_flags, add_arg); 1959 ng_worklist_remove(ngq->q_node); 1960 } else { 1961 /* 1962 * Since there is still something on the queue 1963 * we don't need to change the PENDING flag. 1964 */ 1965 atomic_add_long(&ngq->q_flags, add_arg); 1966 /* 1967 * If we see more doable work, make sure we are 1968 * on the work queue. 1969 */ 1970 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) { 1971 ng_setisr(ngq->q_node); 1972 } 1973 } 1974 CTR6(KTR_NET, "%20s: node [%x] (%p) returning item %p as %s; " 1975 "queue flags 0x%lx", __func__, 1976 ngq->q_node->nd_ID, ngq->q_node, item, *rw ? "WRITER" : "READER" , 1977 ngq->q_flags); 1978 return (item); 1979 } 1980 1981 /* 1982 * Queue a packet to be picked up by someone else. 1983 * We really don't care who, but we can't or don't want to hang around 1984 * to process it ourselves. We are probably an interrupt routine.. 1985 * If the queue could be run, flag the netisr handler to start. 1986 */ 1987 static __inline void 1988 ng_queue_rw(struct ng_queue * ngq, item_p item, int rw) 1989 { 1990 mtx_assert(&ngq->q_mtx, MA_OWNED); 1991 1992 if (rw == NGQRW_W) 1993 NGI_SET_WRITER(item); 1994 else 1995 NGI_SET_READER(item); 1996 item->el_next = NULL; /* maybe not needed */ 1997 *ngq->last = item; 1998 CTR5(KTR_NET, "%20s: node [%x] (%p) queued item %p as %s", __func__, 1999 ngq->q_node->nd_ID, ngq->q_node, item, rw ? "WRITER" : "READER" ); 2000 /* 2001 * If it was the first item in the queue then we need to 2002 * set the last pointer and the type flags. 2003 */ 2004 if (ngq->last == &(ngq->queue)) { 2005 atomic_add_long(&ngq->q_flags, OP_PENDING); 2006 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__, 2007 ngq->q_node->nd_ID, ngq->q_node); 2008 } 2009 2010 ngq->last = &(item->el_next); 2011 /* 2012 * We can take the worklist lock with the node locked 2013 * BUT NOT THE REVERSE! 2014 */ 2015 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2016 ng_setisr(ngq->q_node); 2017 } 2018 2019 2020 /* 2021 * This function 'cheats' in that it first tries to 'grab' the use of the 2022 * node, without going through the mutex. We can do this becasue of the 2023 * semantics of the lock. The semantics include a clause that says that the 2024 * value of the readers count is invalid if the WRITER_ACTIVE flag is set. It 2025 * also says that the WRITER_ACTIVE flag cannot be set if the readers count 2026 * is not zero. Note that this talks about what is valid to SET the 2027 * WRITER_ACTIVE flag, because from the moment it is set, the value if the 2028 * reader count is immaterial, and not valid. The two 'pending' flags have a 2029 * similar effect, in that If they are orthogonal to the two active fields in 2030 * how they are set, but if either is set, the attempted 'grab' need to be 2031 * backed out because there is earlier work, and we maintain ordering in the 2032 * queue. The result of this is that the reader request can try obtain use of 2033 * the node with only a single atomic addition, and without any of the mutex 2034 * overhead. If this fails the operation degenerates to the same as for other 2035 * cases. 2036 * 2037 */ 2038 static __inline item_p 2039 ng_acquire_read(struct ng_queue *ngq, item_p item) 2040 { 2041 KASSERT(ngq != &ng_deadnode.nd_input_queue, 2042 ("%s: working on deadnode", __func__)); 2043 2044 /* ######### Hack alert ######### */ 2045 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 2046 if ((ngq->q_flags & NGQ_RMASK) == 0) { 2047 /* Successfully grabbed node */ 2048 CTR4(KTR_NET, "%20s: node [%x] (%p) fast acquired item %p", 2049 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2050 return (item); 2051 } 2052 /* undo the damage if we didn't succeed */ 2053 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 2054 2055 /* ######### End Hack alert ######### */ 2056 NG_QUEUE_LOCK(ngq); 2057 /* 2058 * Try again. Another processor (or interrupt for that matter) may 2059 * have removed the last queued item that was stopping us from 2060 * running, between the previous test, and the moment that we took 2061 * the mutex. (Or maybe a writer completed.) 2062 * Even if another fast-track reader hits during this period 2063 * we don't care as multiple readers is OK. 2064 */ 2065 if ((ngq->q_flags & NGQ_RMASK) == 0) { 2066 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 2067 NG_QUEUE_UNLOCK(ngq); 2068 CTR4(KTR_NET, "%20s: node [%x] (%p) slow acquired item %p", 2069 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2070 return (item); 2071 } 2072 2073 /* 2074 * and queue the request for later. 2075 */ 2076 ng_queue_rw(ngq, item, NGQRW_R); 2077 NG_QUEUE_UNLOCK(ngq); 2078 2079 return (NULL); 2080 } 2081 2082 static __inline item_p 2083 ng_acquire_write(struct ng_queue *ngq, item_p item) 2084 { 2085 KASSERT(ngq != &ng_deadnode.nd_input_queue, 2086 ("%s: working on deadnode", __func__)); 2087 2088 restart: 2089 NG_QUEUE_LOCK(ngq); 2090 /* 2091 * If there are no readers, no writer, and no pending packets, then 2092 * we can just go ahead. In all other situations we need to queue the 2093 * request 2094 */ 2095 if ((ngq->q_flags & NGQ_WMASK) == 0) { 2096 /* collision could happen *HERE* */ 2097 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE); 2098 NG_QUEUE_UNLOCK(ngq); 2099 if (ngq->q_flags & READER_MASK) { 2100 /* Collision with fast-track reader */ 2101 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2102 goto restart; 2103 } 2104 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p", 2105 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2106 return (item); 2107 } 2108 2109 /* 2110 * and queue the request for later. 2111 */ 2112 ng_queue_rw(ngq, item, NGQRW_W); 2113 NG_QUEUE_UNLOCK(ngq); 2114 2115 return (NULL); 2116 } 2117 2118 #if 0 2119 static __inline item_p 2120 ng_upgrade_write(struct ng_queue *ngq, item_p item) 2121 { 2122 KASSERT(ngq != &ng_deadnode.nd_input_queue, 2123 ("%s: working on deadnode", __func__)); 2124 2125 NGI_SET_WRITER(item); 2126 2127 mtx_lock_spin(&(ngq->q_mtx)); 2128 2129 /* 2130 * There will never be no readers as we are there ourselves. 2131 * Set the WRITER_ACTIVE flags ASAP to block out fast track readers. 2132 * The caller we are running from will call ng_leave_read() 2133 * soon, so we must account for that. We must leave again with the 2134 * READER lock. If we find other readers, then 2135 * queue the request for later. However "later" may be rignt now 2136 * if there are no readers. We don't really care if there are queued 2137 * items as we will bypass them anyhow. 2138 */ 2139 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE - READER_INCREMENT); 2140 if (ngq->q_flags & (NGQ_WMASK & ~OP_PENDING) == WRITER_ACTIVE) { 2141 mtx_unlock_spin(&(ngq->q_mtx)); 2142 2143 /* It's just us, act on the item. */ 2144 /* will NOT drop writer lock when done */ 2145 ng_apply_item(node, item, 0); 2146 2147 /* 2148 * Having acted on the item, atomically 2149 * down grade back to READER and finish up 2150 */ 2151 atomic_add_long(&ngq->q_flags, 2152 READER_INCREMENT - WRITER_ACTIVE); 2153 2154 /* Our caller will call ng_leave_read() */ 2155 return; 2156 } 2157 /* 2158 * It's not just us active, so queue us AT THE HEAD. 2159 * "Why?" I hear you ask. 2160 * Put us at the head of the queue as we've already been 2161 * through it once. If there is nothing else waiting, 2162 * set the correct flags. 2163 */ 2164 if ((item->el_next = ngq->queue) == NULL) { 2165 /* 2166 * Set up the "last" pointer. 2167 * We are the only (and thus last) item 2168 */ 2169 ngq->last = &(item->el_next); 2170 2171 /* We've gone from, 0 to 1 item in the queue */ 2172 atomic_add_long(&ngq->q_flags, OP_PENDING); 2173 2174 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__, 2175 ngq->q_node->nd_ID, ngq->q_node); 2176 }; 2177 ngq->queue = item; 2178 CTR5(KTR_NET, "%20s: node [%x] (%p) requeued item %p as WRITER", 2179 __func__, ngq->q_node->nd_ID, ngq->q_node, item ); 2180 2181 /* Reverse what we did above. That downgrades us back to reader */ 2182 atomic_add_long(&ngq->q_flags, READER_INCREMENT - WRITER_ACTIVE); 2183 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2184 ng_setisr(ngq->q_node); 2185 mtx_unlock_spin(&(ngq->q_mtx)); 2186 2187 return; 2188 } 2189 2190 #endif 2191 2192 static __inline void 2193 ng_leave_read(struct ng_queue *ngq) 2194 { 2195 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 2196 } 2197 2198 static __inline void 2199 ng_leave_write(struct ng_queue *ngq) 2200 { 2201 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2202 } 2203 2204 static void 2205 ng_flush_input_queue(struct ng_queue * ngq) 2206 { 2207 item_p item; 2208 2209 NG_QUEUE_LOCK(ngq); 2210 while (ngq->queue) { 2211 item = ngq->queue; 2212 ngq->queue = item->el_next; 2213 if (ngq->last == &(item->el_next)) { 2214 ngq->last = &(ngq->queue); 2215 atomic_add_long(&ngq->q_flags, -OP_PENDING); 2216 } 2217 NG_QUEUE_UNLOCK(ngq); 2218 2219 /* If the item is supplying a callback, call it with an error */ 2220 if (item->apply != NULL) { 2221 (item->apply)(item->context, ENOENT); 2222 item->apply = NULL; 2223 } 2224 NG_FREE_ITEM(item); 2225 NG_QUEUE_LOCK(ngq); 2226 } 2227 /* 2228 * Take us off the work queue if we are there. 2229 * We definately have no work to be done. 2230 */ 2231 ng_worklist_remove(ngq->q_node); 2232 NG_QUEUE_UNLOCK(ngq); 2233 } 2234 2235 /*********************************************************************** 2236 * Externally visible method for sending or queueing messages or data. 2237 ***********************************************************************/ 2238 2239 /* 2240 * The module code should have filled out the item correctly by this stage: 2241 * Common: 2242 * reference to destination node. 2243 * Reference to destination rcv hook if relevant. 2244 * Data: 2245 * pointer to mbuf 2246 * Control_Message: 2247 * pointer to msg. 2248 * ID of original sender node. (return address) 2249 * Function: 2250 * Function pointer 2251 * void * argument 2252 * integer argument 2253 * 2254 * The nodes have several routines and macros to help with this task: 2255 */ 2256 2257 int 2258 ng_snd_item(item_p item, int flags) 2259 { 2260 hook_p hook = NGI_HOOK(item); 2261 node_p node = NGI_NODE(item); 2262 int queue, rw; 2263 struct ng_queue * ngq = &node->nd_input_queue; 2264 int error = 0; 2265 2266 #ifdef NETGRAPH_DEBUG 2267 _ngi_check(item, __FILE__, __LINE__); 2268 #endif 2269 2270 queue = (flags & NG_QUEUE) ? 1 : 0; 2271 2272 if (item == NULL) { 2273 TRAP_ERROR(); 2274 return (EINVAL); /* failed to get queue element */ 2275 } 2276 if (node == NULL) { 2277 NG_FREE_ITEM(item); 2278 TRAP_ERROR(); 2279 return (EINVAL); /* No address */ 2280 } 2281 switch(item->el_flags & NGQF_TYPE) { 2282 case NGQF_DATA: 2283 /* 2284 * DATA MESSAGE 2285 * Delivered to a node via a non-optional hook. 2286 * Both should be present in the item even though 2287 * the node is derivable from the hook. 2288 * References are held on both by the item. 2289 */ 2290 2291 /* Protect nodes from sending NULL pointers 2292 * to each other 2293 */ 2294 if (NGI_M(item) == NULL) 2295 return (EINVAL); 2296 2297 CHECK_DATA_MBUF(NGI_M(item)); 2298 if (hook == NULL) { 2299 NG_FREE_ITEM(item); 2300 TRAP_ERROR(); 2301 return(EINVAL); 2302 } 2303 if ((NG_HOOK_NOT_VALID(hook)) 2304 || (NG_NODE_NOT_VALID(NG_HOOK_NODE(hook)))) { 2305 NG_FREE_ITEM(item); 2306 return (ENOTCONN); 2307 } 2308 if ((hook->hk_flags & HK_QUEUE)) { 2309 queue = 1; 2310 } 2311 break; 2312 case NGQF_MESG: 2313 /* 2314 * CONTROL MESSAGE 2315 * Delivered to a node. 2316 * Hook is optional. 2317 * References are held by the item on the node and 2318 * the hook if it is present. 2319 */ 2320 if (hook && (hook->hk_flags & HK_QUEUE)) { 2321 queue = 1; 2322 } 2323 break; 2324 case NGQF_FN: 2325 break; 2326 default: 2327 NG_FREE_ITEM(item); 2328 TRAP_ERROR(); 2329 return (EINVAL); 2330 } 2331 switch(item->el_flags & NGQF_RW) { 2332 case NGQF_READER: 2333 rw = NGQRW_R; 2334 break; 2335 case NGQF_WRITER: 2336 rw = NGQRW_W; 2337 break; 2338 default: 2339 panic("%s: invalid item flags %lx", __func__, item->el_flags); 2340 } 2341 2342 /* 2343 * If the node specifies single threading, force writer semantics. 2344 * Similarly, the node may say one hook always produces writers. 2345 * These are overrides. 2346 */ 2347 if ((node->nd_flags & NGF_FORCE_WRITER) 2348 || (hook && (hook->hk_flags & HK_FORCE_WRITER))) 2349 rw = NGQRW_W; 2350 2351 if (queue) { 2352 /* Put it on the queue for that node*/ 2353 #ifdef NETGRAPH_DEBUG 2354 _ngi_check(item, __FILE__, __LINE__); 2355 #endif 2356 NG_QUEUE_LOCK(ngq); 2357 ng_queue_rw(ngq, item, rw); 2358 NG_QUEUE_UNLOCK(ngq); 2359 2360 if (flags & NG_PROGRESS) 2361 return (EINPROGRESS); 2362 else 2363 return (0); 2364 } 2365 2366 /* 2367 * We already decided how we will be queueud or treated. 2368 * Try get the appropriate operating permission. 2369 */ 2370 if (rw == NGQRW_R) 2371 item = ng_acquire_read(ngq, item); 2372 else 2373 item = ng_acquire_write(ngq, item); 2374 2375 2376 if (item == NULL) { 2377 if (flags & NG_PROGRESS) 2378 return (EINPROGRESS); 2379 else 2380 return (0); 2381 } 2382 2383 #ifdef NETGRAPH_DEBUG 2384 _ngi_check(item, __FILE__, __LINE__); 2385 #endif 2386 2387 NGI_GET_NODE(item, node); /* zaps stored node */ 2388 2389 error = ng_apply_item(node, item, rw); /* drops r/w lock when done */ 2390 2391 /* 2392 * If the node goes away when we remove the reference, 2393 * whatever we just did caused it.. whatever we do, DO NOT 2394 * access the node again! 2395 */ 2396 if (NG_NODE_UNREF(node) == 0) { 2397 return (error); 2398 } 2399 2400 NG_QUEUE_LOCK(ngq); 2401 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2402 ng_setisr(ngq->q_node); 2403 NG_QUEUE_UNLOCK(ngq); 2404 2405 return (error); 2406 } 2407 2408 /* 2409 * We have an item that was possibly queued somewhere. 2410 * It should contain all the information needed 2411 * to run it on the appropriate node/hook. 2412 */ 2413 static int 2414 ng_apply_item(node_p node, item_p item, int rw) 2415 { 2416 hook_p hook; 2417 int error = 0; 2418 ng_rcvdata_t *rcvdata; 2419 ng_rcvmsg_t *rcvmsg; 2420 ng_apply_t *apply = NULL; 2421 void *context = NULL; 2422 2423 NGI_GET_HOOK(item, hook); /* clears stored hook */ 2424 #ifdef NETGRAPH_DEBUG 2425 _ngi_check(item, __FILE__, __LINE__); 2426 #endif 2427 2428 /* 2429 * If the item has an "apply" callback, store it. 2430 * Clear item's callback immediately, to avoid an extra call if 2431 * the item is reused by the destination node. 2432 */ 2433 if (item->apply != NULL) { 2434 apply = item->apply; 2435 context = item->context; 2436 item->apply = NULL; 2437 } 2438 2439 switch (item->el_flags & NGQF_TYPE) { 2440 case NGQF_DATA: 2441 /* 2442 * Check things are still ok as when we were queued. 2443 */ 2444 if ((hook == NULL) 2445 || NG_HOOK_NOT_VALID(hook) 2446 || NG_NODE_NOT_VALID(node) ) { 2447 error = EIO; 2448 NG_FREE_ITEM(item); 2449 break; 2450 } 2451 /* 2452 * If no receive method, just silently drop it. 2453 * Give preference to the hook over-ride method 2454 */ 2455 if ((!(rcvdata = hook->hk_rcvdata)) 2456 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) { 2457 error = 0; 2458 NG_FREE_ITEM(item); 2459 break; 2460 } 2461 error = (*rcvdata)(hook, item); 2462 break; 2463 case NGQF_MESG: 2464 if (hook) { 2465 if (NG_HOOK_NOT_VALID(hook)) { 2466 /* 2467 * The hook has been zapped then we can't 2468 * use it. Immediately drop its reference. 2469 * The message may not need it. 2470 */ 2471 NG_HOOK_UNREF(hook); 2472 hook = NULL; 2473 } 2474 } 2475 /* 2476 * Similarly, if the node is a zombie there is 2477 * nothing we can do with it, drop everything. 2478 */ 2479 if (NG_NODE_NOT_VALID(node)) { 2480 TRAP_ERROR(); 2481 error = EINVAL; 2482 NG_FREE_ITEM(item); 2483 } else { 2484 /* 2485 * Call the appropriate message handler for the object. 2486 * It is up to the message handler to free the message. 2487 * If it's a generic message, handle it generically, 2488 * otherwise call the type's message handler 2489 * (if it exists) 2490 * XXX (race). Remember that a queued message may 2491 * reference a node or hook that has just been 2492 * invalidated. It will exist as the queue code 2493 * is holding a reference, but.. 2494 */ 2495 2496 struct ng_mesg *msg = NGI_MSG(item); 2497 2498 /* 2499 * check if the generic handler owns it. 2500 */ 2501 if ((msg->header.typecookie == NGM_GENERIC_COOKIE) 2502 && ((msg->header.flags & NGF_RESP) == 0)) { 2503 error = ng_generic_msg(node, item, hook); 2504 break; 2505 } 2506 /* 2507 * Now see if there is a handler (hook or node specific) 2508 * in the target node. If none, silently discard. 2509 */ 2510 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) 2511 && (!(rcvmsg = node->nd_type->rcvmsg))) { 2512 TRAP_ERROR(); 2513 error = 0; 2514 NG_FREE_ITEM(item); 2515 break; 2516 } 2517 error = (*rcvmsg)(node, item, hook); 2518 } 2519 break; 2520 case NGQF_FN: 2521 /* 2522 * We have to implicitly trust the hook, 2523 * as some of these are used for system purposes 2524 * where the hook is invalid. In the case of 2525 * the shutdown message we allow it to hit 2526 * even if the node is invalid. 2527 */ 2528 if ((NG_NODE_NOT_VALID(node)) 2529 && (NGI_FN(item) != &ng_rmnode)) { 2530 TRAP_ERROR(); 2531 error = EINVAL; 2532 NG_FREE_ITEM(item); 2533 break; 2534 } 2535 (*NGI_FN(item))(node, hook, NGI_ARG1(item), NGI_ARG2(item)); 2536 NG_FREE_ITEM(item); 2537 break; 2538 2539 } 2540 /* 2541 * We held references on some of the resources 2542 * that we took from the item. Now that we have 2543 * finished doing everything, drop those references. 2544 */ 2545 if (hook) { 2546 NG_HOOK_UNREF(hook); 2547 } 2548 2549 if (rw == NGQRW_R) { 2550 ng_leave_read(&node->nd_input_queue); 2551 } else { 2552 ng_leave_write(&node->nd_input_queue); 2553 } 2554 2555 /* Apply callback. */ 2556 if (apply != NULL) 2557 (*apply)(context, error); 2558 2559 return (error); 2560 } 2561 2562 /*********************************************************************** 2563 * Implement the 'generic' control messages 2564 ***********************************************************************/ 2565 static int 2566 ng_generic_msg(node_p here, item_p item, hook_p lasthook) 2567 { 2568 int error = 0; 2569 struct ng_mesg *msg; 2570 struct ng_mesg *resp = NULL; 2571 2572 NGI_GET_MSG(item, msg); 2573 if (msg->header.typecookie != NGM_GENERIC_COOKIE) { 2574 TRAP_ERROR(); 2575 error = EINVAL; 2576 goto out; 2577 } 2578 switch (msg->header.cmd) { 2579 case NGM_SHUTDOWN: 2580 ng_rmnode(here, NULL, NULL, 0); 2581 break; 2582 case NGM_MKPEER: 2583 { 2584 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data; 2585 2586 if (msg->header.arglen != sizeof(*mkp)) { 2587 TRAP_ERROR(); 2588 error = EINVAL; 2589 break; 2590 } 2591 mkp->type[sizeof(mkp->type) - 1] = '\0'; 2592 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0'; 2593 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0'; 2594 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type); 2595 break; 2596 } 2597 case NGM_CONNECT: 2598 { 2599 struct ngm_connect *const con = 2600 (struct ngm_connect *) msg->data; 2601 node_p node2; 2602 2603 if (msg->header.arglen != sizeof(*con)) { 2604 TRAP_ERROR(); 2605 error = EINVAL; 2606 break; 2607 } 2608 con->path[sizeof(con->path) - 1] = '\0'; 2609 con->ourhook[sizeof(con->ourhook) - 1] = '\0'; 2610 con->peerhook[sizeof(con->peerhook) - 1] = '\0'; 2611 /* Don't forget we get a reference.. */ 2612 error = ng_path2noderef(here, con->path, &node2, NULL); 2613 if (error) 2614 break; 2615 error = ng_con_nodes(here, con->ourhook, node2, con->peerhook); 2616 NG_NODE_UNREF(node2); 2617 break; 2618 } 2619 case NGM_NAME: 2620 { 2621 struct ngm_name *const nam = (struct ngm_name *) msg->data; 2622 2623 if (msg->header.arglen != sizeof(*nam)) { 2624 TRAP_ERROR(); 2625 error = EINVAL; 2626 break; 2627 } 2628 nam->name[sizeof(nam->name) - 1] = '\0'; 2629 error = ng_name_node(here, nam->name); 2630 break; 2631 } 2632 case NGM_RMHOOK: 2633 { 2634 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data; 2635 hook_p hook; 2636 2637 if (msg->header.arglen != sizeof(*rmh)) { 2638 TRAP_ERROR(); 2639 error = EINVAL; 2640 break; 2641 } 2642 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0'; 2643 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL) 2644 ng_destroy_hook(hook); 2645 break; 2646 } 2647 case NGM_NODEINFO: 2648 { 2649 struct nodeinfo *ni; 2650 2651 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT); 2652 if (resp == NULL) { 2653 error = ENOMEM; 2654 break; 2655 } 2656 2657 /* Fill in node info */ 2658 ni = (struct nodeinfo *) resp->data; 2659 if (NG_NODE_HAS_NAME(here)) 2660 strcpy(ni->name, NG_NODE_NAME(here)); 2661 strcpy(ni->type, here->nd_type->name); 2662 ni->id = ng_node2ID(here); 2663 ni->hooks = here->nd_numhooks; 2664 break; 2665 } 2666 case NGM_LISTHOOKS: 2667 { 2668 const int nhooks = here->nd_numhooks; 2669 struct hooklist *hl; 2670 struct nodeinfo *ni; 2671 hook_p hook; 2672 2673 /* Get response struct */ 2674 NG_MKRESPONSE(resp, msg, sizeof(*hl) 2675 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT); 2676 if (resp == NULL) { 2677 error = ENOMEM; 2678 break; 2679 } 2680 hl = (struct hooklist *) resp->data; 2681 ni = &hl->nodeinfo; 2682 2683 /* Fill in node info */ 2684 if (NG_NODE_HAS_NAME(here)) 2685 strcpy(ni->name, NG_NODE_NAME(here)); 2686 strcpy(ni->type, here->nd_type->name); 2687 ni->id = ng_node2ID(here); 2688 2689 /* Cycle through the linked list of hooks */ 2690 ni->hooks = 0; 2691 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) { 2692 struct linkinfo *const link = &hl->link[ni->hooks]; 2693 2694 if (ni->hooks >= nhooks) { 2695 log(LOG_ERR, "%s: number of %s changed\n", 2696 __func__, "hooks"); 2697 break; 2698 } 2699 if (NG_HOOK_NOT_VALID(hook)) 2700 continue; 2701 strcpy(link->ourhook, NG_HOOK_NAME(hook)); 2702 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook)); 2703 if (NG_PEER_NODE_NAME(hook)[0] != '\0') 2704 strcpy(link->nodeinfo.name, 2705 NG_PEER_NODE_NAME(hook)); 2706 strcpy(link->nodeinfo.type, 2707 NG_PEER_NODE(hook)->nd_type->name); 2708 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook)); 2709 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks; 2710 ni->hooks++; 2711 } 2712 break; 2713 } 2714 2715 case NGM_LISTNAMES: 2716 case NGM_LISTNODES: 2717 { 2718 const int unnamed = (msg->header.cmd == NGM_LISTNODES); 2719 struct namelist *nl; 2720 node_p node; 2721 int num = 0; 2722 2723 mtx_lock(&ng_nodelist_mtx); 2724 /* Count number of nodes */ 2725 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2726 if (NG_NODE_IS_VALID(node) 2727 && (unnamed || NG_NODE_HAS_NAME(node))) { 2728 num++; 2729 } 2730 } 2731 mtx_unlock(&ng_nodelist_mtx); 2732 2733 /* Get response struct */ 2734 NG_MKRESPONSE(resp, msg, sizeof(*nl) 2735 + (num * sizeof(struct nodeinfo)), M_NOWAIT); 2736 if (resp == NULL) { 2737 error = ENOMEM; 2738 break; 2739 } 2740 nl = (struct namelist *) resp->data; 2741 2742 /* Cycle through the linked list of nodes */ 2743 nl->numnames = 0; 2744 mtx_lock(&ng_nodelist_mtx); 2745 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2746 struct nodeinfo *const np = &nl->nodeinfo[nl->numnames]; 2747 2748 if (NG_NODE_NOT_VALID(node)) 2749 continue; 2750 if (!unnamed && (! NG_NODE_HAS_NAME(node))) 2751 continue; 2752 if (nl->numnames >= num) { 2753 log(LOG_ERR, "%s: number of %s changed\n", 2754 __func__, "nodes"); 2755 break; 2756 } 2757 if (NG_NODE_HAS_NAME(node)) 2758 strcpy(np->name, NG_NODE_NAME(node)); 2759 strcpy(np->type, node->nd_type->name); 2760 np->id = ng_node2ID(node); 2761 np->hooks = node->nd_numhooks; 2762 nl->numnames++; 2763 } 2764 mtx_unlock(&ng_nodelist_mtx); 2765 break; 2766 } 2767 2768 case NGM_LISTTYPES: 2769 { 2770 struct typelist *tl; 2771 struct ng_type *type; 2772 int num = 0; 2773 2774 mtx_lock(&ng_typelist_mtx); 2775 /* Count number of types */ 2776 LIST_FOREACH(type, &ng_typelist, types) { 2777 num++; 2778 } 2779 mtx_unlock(&ng_typelist_mtx); 2780 2781 /* Get response struct */ 2782 NG_MKRESPONSE(resp, msg, sizeof(*tl) 2783 + (num * sizeof(struct typeinfo)), M_NOWAIT); 2784 if (resp == NULL) { 2785 error = ENOMEM; 2786 break; 2787 } 2788 tl = (struct typelist *) resp->data; 2789 2790 /* Cycle through the linked list of types */ 2791 tl->numtypes = 0; 2792 mtx_lock(&ng_typelist_mtx); 2793 LIST_FOREACH(type, &ng_typelist, types) { 2794 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes]; 2795 2796 if (tl->numtypes >= num) { 2797 log(LOG_ERR, "%s: number of %s changed\n", 2798 __func__, "types"); 2799 break; 2800 } 2801 strcpy(tp->type_name, type->name); 2802 tp->numnodes = type->refs - 1; /* don't count list */ 2803 tl->numtypes++; 2804 } 2805 mtx_unlock(&ng_typelist_mtx); 2806 break; 2807 } 2808 2809 case NGM_BINARY2ASCII: 2810 { 2811 int bufSize = 20 * 1024; /* XXX hard coded constant */ 2812 const struct ng_parse_type *argstype; 2813 const struct ng_cmdlist *c; 2814 struct ng_mesg *binary, *ascii; 2815 2816 /* Data area must contain a valid netgraph message */ 2817 binary = (struct ng_mesg *)msg->data; 2818 if (msg->header.arglen < sizeof(struct ng_mesg) || 2819 (msg->header.arglen - sizeof(struct ng_mesg) < 2820 binary->header.arglen)) { 2821 TRAP_ERROR(); 2822 error = EINVAL; 2823 break; 2824 } 2825 2826 /* Get a response message with lots of room */ 2827 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT); 2828 if (resp == NULL) { 2829 error = ENOMEM; 2830 break; 2831 } 2832 ascii = (struct ng_mesg *)resp->data; 2833 2834 /* Copy binary message header to response message payload */ 2835 bcopy(binary, ascii, sizeof(*binary)); 2836 2837 /* Find command by matching typecookie and command number */ 2838 for (c = here->nd_type->cmdlist; 2839 c != NULL && c->name != NULL; c++) { 2840 if (binary->header.typecookie == c->cookie 2841 && binary->header.cmd == c->cmd) 2842 break; 2843 } 2844 if (c == NULL || c->name == NULL) { 2845 for (c = ng_generic_cmds; c->name != NULL; c++) { 2846 if (binary->header.typecookie == c->cookie 2847 && binary->header.cmd == c->cmd) 2848 break; 2849 } 2850 if (c->name == NULL) { 2851 NG_FREE_MSG(resp); 2852 error = ENOSYS; 2853 break; 2854 } 2855 } 2856 2857 /* Convert command name to ASCII */ 2858 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr), 2859 "%s", c->name); 2860 2861 /* Convert command arguments to ASCII */ 2862 argstype = (binary->header.flags & NGF_RESP) ? 2863 c->respType : c->mesgType; 2864 if (argstype == NULL) { 2865 *ascii->data = '\0'; 2866 } else { 2867 if ((error = ng_unparse(argstype, 2868 (u_char *)binary->data, 2869 ascii->data, bufSize)) != 0) { 2870 NG_FREE_MSG(resp); 2871 break; 2872 } 2873 } 2874 2875 /* Return the result as struct ng_mesg plus ASCII string */ 2876 bufSize = strlen(ascii->data) + 1; 2877 ascii->header.arglen = bufSize; 2878 resp->header.arglen = sizeof(*ascii) + bufSize; 2879 break; 2880 } 2881 2882 case NGM_ASCII2BINARY: 2883 { 2884 int bufSize = 2000; /* XXX hard coded constant */ 2885 const struct ng_cmdlist *c; 2886 const struct ng_parse_type *argstype; 2887 struct ng_mesg *ascii, *binary; 2888 int off = 0; 2889 2890 /* Data area must contain at least a struct ng_mesg + '\0' */ 2891 ascii = (struct ng_mesg *)msg->data; 2892 if ((msg->header.arglen < sizeof(*ascii) + 1) || 2893 (ascii->header.arglen < 1) || 2894 (msg->header.arglen < sizeof(*ascii) + 2895 ascii->header.arglen)) { 2896 TRAP_ERROR(); 2897 error = EINVAL; 2898 break; 2899 } 2900 ascii->data[ascii->header.arglen - 1] = '\0'; 2901 2902 /* Get a response message with lots of room */ 2903 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT); 2904 if (resp == NULL) { 2905 error = ENOMEM; 2906 break; 2907 } 2908 binary = (struct ng_mesg *)resp->data; 2909 2910 /* Copy ASCII message header to response message payload */ 2911 bcopy(ascii, binary, sizeof(*ascii)); 2912 2913 /* Find command by matching ASCII command string */ 2914 for (c = here->nd_type->cmdlist; 2915 c != NULL && c->name != NULL; c++) { 2916 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2917 break; 2918 } 2919 if (c == NULL || c->name == NULL) { 2920 for (c = ng_generic_cmds; c->name != NULL; c++) { 2921 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2922 break; 2923 } 2924 if (c->name == NULL) { 2925 NG_FREE_MSG(resp); 2926 error = ENOSYS; 2927 break; 2928 } 2929 } 2930 2931 /* Convert command name to binary */ 2932 binary->header.cmd = c->cmd; 2933 binary->header.typecookie = c->cookie; 2934 2935 /* Convert command arguments to binary */ 2936 argstype = (binary->header.flags & NGF_RESP) ? 2937 c->respType : c->mesgType; 2938 if (argstype == NULL) { 2939 bufSize = 0; 2940 } else { 2941 if ((error = ng_parse(argstype, ascii->data, 2942 &off, (u_char *)binary->data, &bufSize)) != 0) { 2943 NG_FREE_MSG(resp); 2944 break; 2945 } 2946 } 2947 2948 /* Return the result */ 2949 binary->header.arglen = bufSize; 2950 resp->header.arglen = sizeof(*binary) + bufSize; 2951 break; 2952 } 2953 2954 case NGM_TEXT_CONFIG: 2955 case NGM_TEXT_STATUS: 2956 /* 2957 * This one is tricky as it passes the command down to the 2958 * actual node, even though it is a generic type command. 2959 * This means we must assume that the item/msg is already freed 2960 * when control passes back to us. 2961 */ 2962 if (here->nd_type->rcvmsg != NULL) { 2963 NGI_MSG(item) = msg; /* put it back as we found it */ 2964 return((*here->nd_type->rcvmsg)(here, item, lasthook)); 2965 } 2966 /* Fall through if rcvmsg not supported */ 2967 default: 2968 TRAP_ERROR(); 2969 error = EINVAL; 2970 } 2971 /* 2972 * Sometimes a generic message may be statically allocated 2973 * to avoid problems with allocating when in tight memeory situations. 2974 * Don't free it if it is so. 2975 * I break them appart here, because erros may cause a free if the item 2976 * in which case we'd be doing it twice. 2977 * they are kept together above, to simplify freeing. 2978 */ 2979 out: 2980 NG_RESPOND_MSG(error, here, item, resp); 2981 if (msg) 2982 NG_FREE_MSG(msg); 2983 return (error); 2984 } 2985 2986 /************************************************************************ 2987 Queue element get/free routines 2988 ************************************************************************/ 2989 2990 uma_zone_t ng_qzone; 2991 static int maxalloc = 512; /* limit the damage of a leak */ 2992 2993 TUNABLE_INT("net.graph.maxalloc", &maxalloc); 2994 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc, 2995 0, "Maximum number of queue items to allocate"); 2996 2997 #ifdef NETGRAPH_DEBUG 2998 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist); 2999 static int allocated; /* number of items malloc'd */ 3000 #endif 3001 3002 /* 3003 * Get a queue entry. 3004 * This is usually called when a packet first enters netgraph. 3005 * By definition, this is usually from an interrupt, or from a user. 3006 * Users are not so important, but try be quick for the times that it's 3007 * an interrupt. 3008 */ 3009 static __inline item_p 3010 ng_getqblk(int flags) 3011 { 3012 item_p item = NULL; 3013 int wait; 3014 3015 wait = (flags & NG_WAITOK) ? M_WAITOK : M_NOWAIT; 3016 3017 item = uma_zalloc(ng_qzone, wait | M_ZERO); 3018 3019 #ifdef NETGRAPH_DEBUG 3020 if (item) { 3021 mtx_lock(&ngq_mtx); 3022 TAILQ_INSERT_TAIL(&ng_itemlist, item, all); 3023 allocated++; 3024 mtx_unlock(&ngq_mtx); 3025 } 3026 #endif 3027 3028 return (item); 3029 } 3030 3031 /* 3032 * Release a queue entry 3033 */ 3034 void 3035 ng_free_item(item_p item) 3036 { 3037 KASSERT(item->apply == NULL, ("%s: leaking apply callback", __func__)); 3038 3039 /* 3040 * The item may hold resources on it's own. We need to free 3041 * these before we can free the item. What they are depends upon 3042 * what kind of item it is. it is important that nodes zero 3043 * out pointers to resources that they remove from the item 3044 * or we release them again here. 3045 */ 3046 switch (item->el_flags & NGQF_TYPE) { 3047 case NGQF_DATA: 3048 /* If we have an mbuf still attached.. */ 3049 NG_FREE_M(_NGI_M(item)); 3050 break; 3051 case NGQF_MESG: 3052 _NGI_RETADDR(item) = 0; 3053 NG_FREE_MSG(_NGI_MSG(item)); 3054 break; 3055 case NGQF_FN: 3056 /* nothing to free really, */ 3057 _NGI_FN(item) = NULL; 3058 _NGI_ARG1(item) = NULL; 3059 _NGI_ARG2(item) = 0; 3060 case NGQF_UNDEF: 3061 break; 3062 } 3063 /* If we still have a node or hook referenced... */ 3064 _NGI_CLR_NODE(item); 3065 _NGI_CLR_HOOK(item); 3066 3067 #ifdef NETGRAPH_DEBUG 3068 mtx_lock(&ngq_mtx); 3069 TAILQ_REMOVE(&ng_itemlist, item, all); 3070 allocated--; 3071 mtx_unlock(&ngq_mtx); 3072 #endif 3073 uma_zfree(ng_qzone, item); 3074 } 3075 3076 /************************************************************************ 3077 Module routines 3078 ************************************************************************/ 3079 3080 /* 3081 * Handle the loading/unloading of a netgraph node type module 3082 */ 3083 int 3084 ng_mod_event(module_t mod, int event, void *data) 3085 { 3086 struct ng_type *const type = data; 3087 int s, error = 0; 3088 3089 switch (event) { 3090 case MOD_LOAD: 3091 3092 /* Register new netgraph node type */ 3093 s = splnet(); 3094 if ((error = ng_newtype(type)) != 0) { 3095 splx(s); 3096 break; 3097 } 3098 3099 /* Call type specific code */ 3100 if (type->mod_event != NULL) 3101 if ((error = (*type->mod_event)(mod, event, data))) { 3102 mtx_lock(&ng_typelist_mtx); 3103 type->refs--; /* undo it */ 3104 LIST_REMOVE(type, types); 3105 mtx_unlock(&ng_typelist_mtx); 3106 } 3107 splx(s); 3108 break; 3109 3110 case MOD_UNLOAD: 3111 s = splnet(); 3112 if (type->refs > 1) { /* make sure no nodes exist! */ 3113 error = EBUSY; 3114 } else { 3115 if (type->refs == 0) { 3116 /* failed load, nothing to undo */ 3117 splx(s); 3118 break; 3119 } 3120 if (type->mod_event != NULL) { /* check with type */ 3121 error = (*type->mod_event)(mod, event, data); 3122 if (error != 0) { /* type refuses.. */ 3123 splx(s); 3124 break; 3125 } 3126 } 3127 mtx_lock(&ng_typelist_mtx); 3128 LIST_REMOVE(type, types); 3129 mtx_unlock(&ng_typelist_mtx); 3130 } 3131 splx(s); 3132 break; 3133 3134 default: 3135 if (type->mod_event != NULL) 3136 error = (*type->mod_event)(mod, event, data); 3137 else 3138 error = EOPNOTSUPP; /* XXX ? */ 3139 break; 3140 } 3141 return (error); 3142 } 3143 3144 /* 3145 * Handle loading and unloading for this code. 3146 * The only thing we need to link into is the NETISR strucure. 3147 */ 3148 static int 3149 ngb_mod_event(module_t mod, int event, void *data) 3150 { 3151 int error = 0; 3152 3153 switch (event) { 3154 case MOD_LOAD: 3155 /* Initialize everything. */ 3156 NG_WORKLIST_LOCK_INIT(); 3157 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL, 3158 MTX_DEF); 3159 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL, 3160 MTX_DEF); 3161 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL, 3162 MTX_DEF); 3163 mtx_init(&ng_topo_mtx, "netgraph topology mutex", NULL, 3164 MTX_DEF); 3165 #ifdef NETGRAPH_DEBUG 3166 mtx_init(&ngq_mtx, "netgraph item list mutex", NULL, 3167 MTX_DEF); 3168 #endif 3169 ng_qzone = uma_zcreate("NetGraph items", sizeof(struct ng_item), 3170 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0); 3171 uma_zone_set_max(ng_qzone, maxalloc); 3172 netisr_register(NETISR_NETGRAPH, (netisr_t *)ngintr, NULL, 3173 NETISR_MPSAFE); 3174 break; 3175 case MOD_UNLOAD: 3176 /* You can't unload it because an interface may be using it. */ 3177 error = EBUSY; 3178 break; 3179 default: 3180 error = EOPNOTSUPP; 3181 break; 3182 } 3183 return (error); 3184 } 3185 3186 static moduledata_t netgraph_mod = { 3187 "netgraph", 3188 ngb_mod_event, 3189 (NULL) 3190 }; 3191 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_MIDDLE); 3192 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family"); 3193 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,""); 3194 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, ""); 3195 3196 #ifdef NETGRAPH_DEBUG 3197 void 3198 dumphook (hook_p hook, char *file, int line) 3199 { 3200 printf("hook: name %s, %d refs, Last touched:\n", 3201 _NG_HOOK_NAME(hook), hook->hk_refs); 3202 printf(" Last active @ %s, line %d\n", 3203 hook->lastfile, hook->lastline); 3204 if (line) { 3205 printf(" problem discovered at file %s, line %d\n", file, line); 3206 } 3207 } 3208 3209 void 3210 dumpnode(node_p node, char *file, int line) 3211 { 3212 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n", 3213 _NG_NODE_ID(node), node->nd_type->name, 3214 node->nd_numhooks, node->nd_flags, 3215 node->nd_refs, node->nd_name); 3216 printf(" Last active @ %s, line %d\n", 3217 node->lastfile, node->lastline); 3218 if (line) { 3219 printf(" problem discovered at file %s, line %d\n", file, line); 3220 } 3221 } 3222 3223 void 3224 dumpitem(item_p item, char *file, int line) 3225 { 3226 printf(" ACTIVE item, last used at %s, line %d", 3227 item->lastfile, item->lastline); 3228 switch(item->el_flags & NGQF_TYPE) { 3229 case NGQF_DATA: 3230 printf(" - [data]\n"); 3231 break; 3232 case NGQF_MESG: 3233 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item)); 3234 break; 3235 case NGQF_FN: 3236 printf(" - fn@%p (%p, %p, %p, %d (%x))\n", 3237 item->body.fn.fn_fn, 3238 _NGI_NODE(item), 3239 _NGI_HOOK(item), 3240 item->body.fn.fn_arg1, 3241 item->body.fn.fn_arg2, 3242 item->body.fn.fn_arg2); 3243 break; 3244 case NGQF_UNDEF: 3245 printf(" - UNDEFINED!\n"); 3246 } 3247 if (line) { 3248 printf(" problem discovered at file %s, line %d\n", file, line); 3249 if (_NGI_NODE(item)) { 3250 printf("node %p ([%x])\n", 3251 _NGI_NODE(item), ng_node2ID(_NGI_NODE(item))); 3252 } 3253 } 3254 } 3255 3256 static void 3257 ng_dumpitems(void) 3258 { 3259 item_p item; 3260 int i = 1; 3261 TAILQ_FOREACH(item, &ng_itemlist, all) { 3262 printf("[%d] ", i++); 3263 dumpitem(item, NULL, 0); 3264 } 3265 } 3266 3267 static void 3268 ng_dumpnodes(void) 3269 { 3270 node_p node; 3271 int i = 1; 3272 mtx_lock(&ng_nodelist_mtx); 3273 SLIST_FOREACH(node, &ng_allnodes, nd_all) { 3274 printf("[%d] ", i++); 3275 dumpnode(node, NULL, 0); 3276 } 3277 mtx_unlock(&ng_nodelist_mtx); 3278 } 3279 3280 static void 3281 ng_dumphooks(void) 3282 { 3283 hook_p hook; 3284 int i = 1; 3285 mtx_lock(&ng_nodelist_mtx); 3286 SLIST_FOREACH(hook, &ng_allhooks, hk_all) { 3287 printf("[%d] ", i++); 3288 dumphook(hook, NULL, 0); 3289 } 3290 mtx_unlock(&ng_nodelist_mtx); 3291 } 3292 3293 static int 3294 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS) 3295 { 3296 int error; 3297 int val; 3298 int i; 3299 3300 val = allocated; 3301 i = 1; 3302 error = sysctl_handle_int(oidp, &val, 0, req); 3303 if (error != 0 || req->newptr == NULL) 3304 return (error); 3305 if (val == 42) { 3306 ng_dumpitems(); 3307 ng_dumpnodes(); 3308 ng_dumphooks(); 3309 } 3310 return (0); 3311 } 3312 3313 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW, 3314 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items"); 3315 #endif /* NETGRAPH_DEBUG */ 3316 3317 3318 /*********************************************************************** 3319 * Worklist routines 3320 **********************************************************************/ 3321 /* NETISR thread enters here */ 3322 /* 3323 * Pick a node off the list of nodes with work, 3324 * try get an item to process off it. 3325 * If there are no more, remove the node from the list. 3326 */ 3327 static void 3328 ngintr(void) 3329 { 3330 item_p item; 3331 node_p node = NULL; 3332 3333 for (;;) { 3334 NG_WORKLIST_LOCK(); 3335 node = TAILQ_FIRST(&ng_worklist); 3336 if (!node) { 3337 NG_WORKLIST_UNLOCK(); 3338 break; 3339 } 3340 node->nd_flags &= ~NGF_WORKQ; 3341 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3342 NG_WORKLIST_UNLOCK(); 3343 CTR3(KTR_NET, "%20s: node [%x] (%p) taken off worklist", 3344 __func__, node->nd_ID, node); 3345 /* 3346 * We have the node. We also take over the reference 3347 * that the list had on it. 3348 * Now process as much as you can, until it won't 3349 * let you have another item off the queue. 3350 * All this time, keep the reference 3351 * that lets us be sure that the node still exists. 3352 * Let the reference go at the last minute. 3353 * ng_dequeue will put us back on the worklist 3354 * if there is more too do. This may be of use if there 3355 * are Multiple Processors and multiple Net threads in the 3356 * future. 3357 */ 3358 for (;;) { 3359 int rw; 3360 3361 NG_QUEUE_LOCK(&node->nd_input_queue); 3362 item = ng_dequeue(&node->nd_input_queue, &rw); 3363 if (item == NULL) { 3364 NG_QUEUE_UNLOCK(&node->nd_input_queue); 3365 break; /* go look for another node */ 3366 } else { 3367 NG_QUEUE_UNLOCK(&node->nd_input_queue); 3368 NGI_GET_NODE(item, node); /* zaps stored node */ 3369 ng_apply_item(node, item, rw); 3370 NG_NODE_UNREF(node); 3371 } 3372 } 3373 NG_NODE_UNREF(node); 3374 } 3375 } 3376 3377 static void 3378 ng_worklist_remove(node_p node) 3379 { 3380 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED); 3381 3382 NG_WORKLIST_LOCK(); 3383 if (node->nd_flags & NGF_WORKQ) { 3384 node->nd_flags &= ~NGF_WORKQ; 3385 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3386 NG_WORKLIST_UNLOCK(); 3387 NG_NODE_UNREF(node); 3388 CTR3(KTR_NET, "%20s: node [%x] (%p) removed from worklist", 3389 __func__, node->nd_ID, node); 3390 } else { 3391 NG_WORKLIST_UNLOCK(); 3392 } 3393 } 3394 3395 /* 3396 * XXX 3397 * It's posible that a debugging NG_NODE_REF may need 3398 * to be outside the mutex zone 3399 */ 3400 static void 3401 ng_setisr(node_p node) 3402 { 3403 3404 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED); 3405 3406 if ((node->nd_flags & NGF_WORKQ) == 0) { 3407 /* 3408 * If we are not already on the work queue, 3409 * then put us on. 3410 */ 3411 node->nd_flags |= NGF_WORKQ; 3412 NG_WORKLIST_LOCK(); 3413 TAILQ_INSERT_TAIL(&ng_worklist, node, nd_work); 3414 NG_WORKLIST_UNLOCK(); 3415 NG_NODE_REF(node); /* XXX fafe in mutex? */ 3416 CTR3(KTR_NET, "%20s: node [%x] (%p) put on worklist", __func__, 3417 node->nd_ID, node); 3418 } else 3419 CTR3(KTR_NET, "%20s: node [%x] (%p) already on worklist", 3420 __func__, node->nd_ID, node); 3421 schednetisr(NETISR_NETGRAPH); 3422 } 3423 3424 3425 /*********************************************************************** 3426 * Externally useable functions to set up a queue item ready for sending 3427 ***********************************************************************/ 3428 3429 #ifdef NETGRAPH_DEBUG 3430 #define ITEM_DEBUG_CHECKS \ 3431 do { \ 3432 if (NGI_NODE(item) ) { \ 3433 printf("item already has node"); \ 3434 kdb_enter("has node"); \ 3435 NGI_CLR_NODE(item); \ 3436 } \ 3437 if (NGI_HOOK(item) ) { \ 3438 printf("item already has hook"); \ 3439 kdb_enter("has hook"); \ 3440 NGI_CLR_HOOK(item); \ 3441 } \ 3442 } while (0) 3443 #else 3444 #define ITEM_DEBUG_CHECKS 3445 #endif 3446 3447 /* 3448 * Put mbuf into the item. 3449 * Hook and node references will be removed when the item is dequeued. 3450 * (or equivalent) 3451 * (XXX) Unsafe because no reference held by peer on remote node. 3452 * remote node might go away in this timescale. 3453 * We know the hooks can't go away because that would require getting 3454 * a writer item on both nodes and we must have at least a reader 3455 * here to be able to do this. 3456 * Note that the hook loaded is the REMOTE hook. 3457 * 3458 * This is possibly in the critical path for new data. 3459 */ 3460 item_p 3461 ng_package_data(struct mbuf *m, int flags) 3462 { 3463 item_p item; 3464 3465 if ((item = ng_getqblk(flags)) == NULL) { 3466 NG_FREE_M(m); 3467 return (NULL); 3468 } 3469 ITEM_DEBUG_CHECKS; 3470 item->el_flags = NGQF_DATA | NGQF_READER; 3471 item->el_next = NULL; 3472 NGI_M(item) = m; 3473 return (item); 3474 } 3475 3476 /* 3477 * Allocate a queue item and put items into it.. 3478 * Evaluate the address as this will be needed to queue it and 3479 * to work out what some of the fields should be. 3480 * Hook and node references will be removed when the item is dequeued. 3481 * (or equivalent) 3482 */ 3483 item_p 3484 ng_package_msg(struct ng_mesg *msg, int flags) 3485 { 3486 item_p item; 3487 3488 if ((item = ng_getqblk(flags)) == NULL) { 3489 NG_FREE_MSG(msg); 3490 return (NULL); 3491 } 3492 ITEM_DEBUG_CHECKS; 3493 /* Messages items count as writers unless explicitly exempted. */ 3494 if (msg->header.cmd & NGM_READONLY) 3495 item->el_flags = NGQF_MESG | NGQF_READER; 3496 else 3497 item->el_flags = NGQF_MESG | NGQF_WRITER; 3498 item->el_next = NULL; 3499 /* 3500 * Set the current lasthook into the queue item 3501 */ 3502 NGI_MSG(item) = msg; 3503 NGI_RETADDR(item) = 0; 3504 return (item); 3505 } 3506 3507 3508 3509 #define SET_RETADDR(item, here, retaddr) \ 3510 do { /* Data or fn items don't have retaddrs */ \ 3511 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \ 3512 if (retaddr) { \ 3513 NGI_RETADDR(item) = retaddr; \ 3514 } else { \ 3515 /* \ 3516 * The old return address should be ok. \ 3517 * If there isn't one, use the address \ 3518 * here. \ 3519 */ \ 3520 if (NGI_RETADDR(item) == 0) { \ 3521 NGI_RETADDR(item) \ 3522 = ng_node2ID(here); \ 3523 } \ 3524 } \ 3525 } \ 3526 } while (0) 3527 3528 int 3529 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr) 3530 { 3531 hook_p peer; 3532 node_p peernode; 3533 ITEM_DEBUG_CHECKS; 3534 /* 3535 * Quick sanity check.. 3536 * Since a hook holds a reference on it's node, once we know 3537 * that the peer is still connected (even if invalid,) we know 3538 * that the peer node is present, though maybe invalid. 3539 */ 3540 if ((hook == NULL) 3541 || NG_HOOK_NOT_VALID(hook) 3542 || (NG_HOOK_PEER(hook) == NULL) 3543 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)) 3544 || NG_NODE_NOT_VALID(NG_PEER_NODE(hook))) { 3545 NG_FREE_ITEM(item); 3546 TRAP_ERROR(); 3547 return (ENETDOWN); 3548 } 3549 3550 /* 3551 * Transfer our interest to the other (peer) end. 3552 */ 3553 peer = NG_HOOK_PEER(hook); 3554 NG_HOOK_REF(peer); 3555 NGI_SET_HOOK(item, peer); 3556 peernode = NG_PEER_NODE(hook); 3557 NG_NODE_REF(peernode); 3558 NGI_SET_NODE(item, peernode); 3559 SET_RETADDR(item, here, retaddr); 3560 return (0); 3561 } 3562 3563 int 3564 ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr) 3565 { 3566 node_p dest = NULL; 3567 hook_p hook = NULL; 3568 int error; 3569 3570 ITEM_DEBUG_CHECKS; 3571 /* 3572 * Note that ng_path2noderef increments the reference count 3573 * on the node for us if it finds one. So we don't have to. 3574 */ 3575 error = ng_path2noderef(here, address, &dest, &hook); 3576 if (error) { 3577 NG_FREE_ITEM(item); 3578 return (error); 3579 } 3580 NGI_SET_NODE(item, dest); 3581 if ( hook) { 3582 NG_HOOK_REF(hook); /* don't let it go while on the queue */ 3583 NGI_SET_HOOK(item, hook); 3584 } 3585 SET_RETADDR(item, here, retaddr); 3586 return (0); 3587 } 3588 3589 int 3590 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr) 3591 { 3592 node_p dest; 3593 3594 ITEM_DEBUG_CHECKS; 3595 /* 3596 * Find the target node. 3597 */ 3598 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */ 3599 if (dest == NULL) { 3600 NG_FREE_ITEM(item); 3601 TRAP_ERROR(); 3602 return(EINVAL); 3603 } 3604 /* Fill out the contents */ 3605 NGI_SET_NODE(item, dest); 3606 NGI_CLR_HOOK(item); 3607 SET_RETADDR(item, here, retaddr); 3608 return (0); 3609 } 3610 3611 /* 3612 * special case to send a message to self (e.g. destroy node) 3613 * Possibly indicate an arrival hook too. 3614 * Useful for removing that hook :-) 3615 */ 3616 item_p 3617 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg) 3618 { 3619 item_p item; 3620 3621 /* 3622 * Find the target node. 3623 * If there is a HOOK argument, then use that in preference 3624 * to the address. 3625 */ 3626 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL) { 3627 NG_FREE_MSG(msg); 3628 return (NULL); 3629 } 3630 3631 /* Fill out the contents */ 3632 item->el_flags = NGQF_MESG | NGQF_WRITER; 3633 item->el_next = NULL; 3634 NG_NODE_REF(here); 3635 NGI_SET_NODE(item, here); 3636 if (hook) { 3637 NG_HOOK_REF(hook); 3638 NGI_SET_HOOK(item, hook); 3639 } 3640 NGI_MSG(item) = msg; 3641 NGI_RETADDR(item) = ng_node2ID(here); 3642 return (item); 3643 } 3644 3645 int 3646 ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2, 3647 int flags) 3648 { 3649 item_p item; 3650 3651 if ((item = ng_getqblk(flags)) == NULL) { 3652 return (ENOMEM); 3653 } 3654 item->el_flags = NGQF_FN | NGQF_WRITER; 3655 NG_NODE_REF(node); /* and one for the item */ 3656 NGI_SET_NODE(item, node); 3657 if (hook) { 3658 NG_HOOK_REF(hook); 3659 NGI_SET_HOOK(item, hook); 3660 } 3661 NGI_FN(item) = fn; 3662 NGI_ARG1(item) = arg1; 3663 NGI_ARG2(item) = arg2; 3664 return(ng_snd_item(item, flags)); 3665 } 3666 3667 /* 3668 * Official timeout routines for Netgraph nodes. 3669 */ 3670 static void 3671 ng_callout_trampoline(void *arg) 3672 { 3673 item_p item = arg; 3674 3675 ng_snd_item(item, 0); 3676 } 3677 3678 3679 int 3680 ng_callout(struct callout *c, node_p node, hook_p hook, int ticks, 3681 ng_item_fn *fn, void * arg1, int arg2) 3682 { 3683 item_p item, oitem; 3684 3685 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL) 3686 return (ENOMEM); 3687 3688 item->el_flags = NGQF_FN | NGQF_WRITER; 3689 NG_NODE_REF(node); /* and one for the item */ 3690 NGI_SET_NODE(item, node); 3691 if (hook) { 3692 NG_HOOK_REF(hook); 3693 NGI_SET_HOOK(item, hook); 3694 } 3695 NGI_FN(item) = fn; 3696 NGI_ARG1(item) = arg1; 3697 NGI_ARG2(item) = arg2; 3698 oitem = c->c_arg; 3699 if (callout_reset(c, ticks, &ng_callout_trampoline, item) == 1 && 3700 oitem != NULL) 3701 NG_FREE_ITEM(oitem); 3702 return (0); 3703 } 3704 3705 /* A special modified version of untimeout() */ 3706 int 3707 ng_uncallout(struct callout *c, node_p node) 3708 { 3709 item_p item; 3710 int rval; 3711 3712 KASSERT(c != NULL, ("ng_uncallout: NULL callout")); 3713 KASSERT(node != NULL, ("ng_uncallout: NULL node")); 3714 3715 rval = callout_stop(c); 3716 item = c->c_arg; 3717 /* Do an extra check */ 3718 if ((rval > 0) && (c->c_func == &ng_callout_trampoline) && 3719 (NGI_NODE(item) == node)) { 3720 /* 3721 * We successfully removed it from the queue before it ran 3722 * So now we need to unreference everything that was 3723 * given extra references. (NG_FREE_ITEM does this). 3724 */ 3725 NG_FREE_ITEM(item); 3726 } 3727 c->c_arg = NULL; 3728 3729 return (rval); 3730 } 3731 3732 /* 3733 * Set the address, if none given, give the node here. 3734 */ 3735 void 3736 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr) 3737 { 3738 if (retaddr) { 3739 NGI_RETADDR(item) = retaddr; 3740 } else { 3741 /* 3742 * The old return address should be ok. 3743 * If there isn't one, use the address here. 3744 */ 3745 NGI_RETADDR(item) = ng_node2ID(here); 3746 } 3747 } 3748 3749 #define TESTING 3750 #ifdef TESTING 3751 /* just test all the macros */ 3752 void 3753 ng_macro_test(item_p item); 3754 void 3755 ng_macro_test(item_p item) 3756 { 3757 node_p node = NULL; 3758 hook_p hook = NULL; 3759 struct mbuf *m; 3760 struct ng_mesg *msg; 3761 ng_ID_t retaddr; 3762 int error; 3763 3764 NGI_GET_M(item, m); 3765 NGI_GET_MSG(item, msg); 3766 retaddr = NGI_RETADDR(item); 3767 NG_SEND_DATA(error, hook, m, NULL); 3768 NG_SEND_DATA_ONLY(error, hook, m); 3769 NG_FWD_NEW_DATA(error, item, hook, m); 3770 NG_FWD_ITEM_HOOK(error, item, hook); 3771 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr); 3772 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr); 3773 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr); 3774 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr); 3775 } 3776 #endif /* TESTING */ 3777 3778