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 #include <sys/refcount.h> 63 #include <sys/proc.h> 64 65 #include <net/netisr.h> 66 67 #include <netgraph/ng_message.h> 68 #include <netgraph/netgraph.h> 69 #include <netgraph/ng_parse.h> 70 71 MODULE_VERSION(netgraph, NG_ABI_VERSION); 72 73 /* List of all active nodes */ 74 static LIST_HEAD(, ng_node) ng_nodelist; 75 static struct mtx ng_nodelist_mtx; 76 77 /* Mutex to protect topology events. */ 78 static struct mtx ng_topo_mtx; 79 80 #ifdef NETGRAPH_DEBUG 81 static struct mtx ngq_mtx; /* protects the queue item list */ 82 83 static SLIST_HEAD(, ng_node) ng_allnodes; 84 static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */ 85 static SLIST_HEAD(, ng_hook) ng_allhooks; 86 static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */ 87 88 static void ng_dumpitems(void); 89 static void ng_dumpnodes(void); 90 static void ng_dumphooks(void); 91 92 #endif /* NETGRAPH_DEBUG */ 93 /* 94 * DEAD versions of the structures. 95 * In order to avoid races, it is sometimes neccesary to point 96 * at SOMETHING even though theoretically, the current entity is 97 * INVALID. Use these to avoid these races. 98 */ 99 struct ng_type ng_deadtype = { 100 NG_ABI_VERSION, 101 "dead", 102 NULL, /* modevent */ 103 NULL, /* constructor */ 104 NULL, /* rcvmsg */ 105 NULL, /* shutdown */ 106 NULL, /* newhook */ 107 NULL, /* findhook */ 108 NULL, /* connect */ 109 NULL, /* rcvdata */ 110 NULL, /* disconnect */ 111 NULL, /* cmdlist */ 112 }; 113 114 struct ng_node ng_deadnode = { 115 "dead", 116 &ng_deadtype, 117 NGF_INVALID, 118 1, /* refs */ 119 0, /* numhooks */ 120 NULL, /* private */ 121 0, /* ID */ 122 LIST_HEAD_INITIALIZER(ng_deadnode.hooks), 123 {}, /* all_nodes list entry */ 124 {}, /* id hashtable list entry */ 125 {}, /* workqueue entry */ 126 { 0, 127 {}, /* should never use! (should hang) */ 128 NULL, 129 &ng_deadnode.nd_input_queue.queue, 130 &ng_deadnode 131 }, 132 #ifdef NETGRAPH_DEBUG 133 ND_MAGIC, 134 __FILE__, 135 __LINE__, 136 {NULL} 137 #endif /* NETGRAPH_DEBUG */ 138 }; 139 140 struct ng_hook ng_deadhook = { 141 "dead", 142 NULL, /* private */ 143 HK_INVALID | HK_DEAD, 144 1, /* refs always >= 1 */ 145 0, /* undefined data link type */ 146 &ng_deadhook, /* Peer is self */ 147 &ng_deadnode, /* attached to deadnode */ 148 {}, /* hooks list */ 149 NULL, /* override rcvmsg() */ 150 NULL, /* override rcvdata() */ 151 #ifdef NETGRAPH_DEBUG 152 HK_MAGIC, 153 __FILE__, 154 __LINE__, 155 {NULL} 156 #endif /* NETGRAPH_DEBUG */ 157 }; 158 159 /* 160 * END DEAD STRUCTURES 161 */ 162 /* List nodes with unallocated work */ 163 static TAILQ_HEAD(, ng_node) ng_worklist = TAILQ_HEAD_INITIALIZER(ng_worklist); 164 static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */ 165 166 /* List of installed types */ 167 static LIST_HEAD(, ng_type) ng_typelist; 168 static struct mtx ng_typelist_mtx; 169 170 /* Hash related definitions */ 171 /* XXX Don't need to initialise them because it's a LIST */ 172 #define NG_ID_HASH_SIZE 32 /* most systems wont need even this many */ 173 static LIST_HEAD(, ng_node) ng_ID_hash[NG_ID_HASH_SIZE]; 174 static struct mtx ng_idhash_mtx; 175 /* Method to find a node.. used twice so do it here */ 176 #define NG_IDHASH_FN(ID) ((ID) % (NG_ID_HASH_SIZE)) 177 #define NG_IDHASH_FIND(ID, node) \ 178 do { \ 179 mtx_assert(&ng_idhash_mtx, MA_OWNED); \ 180 LIST_FOREACH(node, &ng_ID_hash[NG_IDHASH_FN(ID)], \ 181 nd_idnodes) { \ 182 if (NG_NODE_IS_VALID(node) \ 183 && (NG_NODE_ID(node) == ID)) { \ 184 break; \ 185 } \ 186 } \ 187 } while (0) 188 189 190 /* Internal functions */ 191 static int ng_add_hook(node_p node, const char *name, hook_p * hookp); 192 static int ng_generic_msg(node_p here, item_p item, hook_p lasthook); 193 static ng_ID_t ng_decodeidname(const char *name); 194 static int ngb_mod_event(module_t mod, int event, void *data); 195 static void ng_worklist_remove(node_p node); 196 static void ngintr(void); 197 static int ng_apply_item(node_p node, item_p item, int rw); 198 static void ng_flush_input_queue(struct ng_queue * ngq); 199 static void ng_setisr(node_p node); 200 static node_p ng_ID2noderef(ng_ID_t ID); 201 static int ng_con_nodes(item_p item, node_p node, const char *name, 202 node_p node2, const char *name2); 203 static int ng_con_part2(node_p node, item_p item, hook_p hook); 204 static int ng_con_part3(node_p node, item_p item, hook_p hook); 205 static int ng_mkpeer(node_p node, const char *name, 206 const char *name2, char *type); 207 208 /* Imported, these used to be externally visible, some may go back. */ 209 void ng_destroy_hook(hook_p hook); 210 node_p ng_name2noderef(node_p node, const char *name); 211 int ng_path2noderef(node_p here, const char *path, 212 node_p *dest, hook_p *lasthook); 213 int ng_make_node(const char *type, node_p *nodepp); 214 int ng_path_parse(char *addr, char **node, char **path, char **hook); 215 void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3); 216 void ng_unname(node_p node); 217 218 219 /* Our own netgraph malloc type */ 220 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages"); 221 MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures"); 222 MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures"); 223 MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", "netgraph item structures"); 224 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage"); 225 226 /* Should not be visible outside this file */ 227 228 #define _NG_ALLOC_HOOK(hook) \ 229 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO) 230 #define _NG_ALLOC_NODE(node) \ 231 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO) 232 233 #define NG_QUEUE_LOCK_INIT(n) \ 234 mtx_init(&(n)->q_mtx, "ng_node", NULL, MTX_DEF) 235 #define NG_QUEUE_LOCK(n) \ 236 mtx_lock(&(n)->q_mtx) 237 #define NG_QUEUE_UNLOCK(n) \ 238 mtx_unlock(&(n)->q_mtx) 239 #define NG_WORKLIST_LOCK_INIT() \ 240 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_DEF) 241 #define NG_WORKLIST_LOCK() \ 242 mtx_lock(&ng_worklist_mtx) 243 #define NG_WORKLIST_UNLOCK() \ 244 mtx_unlock(&ng_worklist_mtx) 245 246 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/ 247 /* 248 * In debug mode: 249 * In an attempt to help track reference count screwups 250 * we do not free objects back to the malloc system, but keep them 251 * in a local cache where we can examine them and keep information safely 252 * after they have been freed. 253 * We use this scheme for nodes and hooks, and to some extent for items. 254 */ 255 static __inline hook_p 256 ng_alloc_hook(void) 257 { 258 hook_p hook; 259 SLIST_ENTRY(ng_hook) temp; 260 mtx_lock(&ng_nodelist_mtx); 261 hook = LIST_FIRST(&ng_freehooks); 262 if (hook) { 263 LIST_REMOVE(hook, hk_hooks); 264 bcopy(&hook->hk_all, &temp, sizeof(temp)); 265 bzero(hook, sizeof(struct ng_hook)); 266 bcopy(&temp, &hook->hk_all, sizeof(temp)); 267 mtx_unlock(&ng_nodelist_mtx); 268 hook->hk_magic = HK_MAGIC; 269 } else { 270 mtx_unlock(&ng_nodelist_mtx); 271 _NG_ALLOC_HOOK(hook); 272 if (hook) { 273 hook->hk_magic = HK_MAGIC; 274 mtx_lock(&ng_nodelist_mtx); 275 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all); 276 mtx_unlock(&ng_nodelist_mtx); 277 } 278 } 279 return (hook); 280 } 281 282 static __inline node_p 283 ng_alloc_node(void) 284 { 285 node_p node; 286 SLIST_ENTRY(ng_node) temp; 287 mtx_lock(&ng_nodelist_mtx); 288 node = LIST_FIRST(&ng_freenodes); 289 if (node) { 290 LIST_REMOVE(node, nd_nodes); 291 bcopy(&node->nd_all, &temp, sizeof(temp)); 292 bzero(node, sizeof(struct ng_node)); 293 bcopy(&temp, &node->nd_all, sizeof(temp)); 294 mtx_unlock(&ng_nodelist_mtx); 295 node->nd_magic = ND_MAGIC; 296 } else { 297 mtx_unlock(&ng_nodelist_mtx); 298 _NG_ALLOC_NODE(node); 299 if (node) { 300 node->nd_magic = ND_MAGIC; 301 mtx_lock(&ng_nodelist_mtx); 302 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all); 303 mtx_unlock(&ng_nodelist_mtx); 304 } 305 } 306 return (node); 307 } 308 309 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0) 310 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0) 311 312 313 #define NG_FREE_HOOK(hook) \ 314 do { \ 315 mtx_lock(&ng_nodelist_mtx); \ 316 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \ 317 hook->hk_magic = 0; \ 318 mtx_unlock(&ng_nodelist_mtx); \ 319 } while (0) 320 321 #define NG_FREE_NODE(node) \ 322 do { \ 323 mtx_lock(&ng_nodelist_mtx); \ 324 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \ 325 node->nd_magic = 0; \ 326 mtx_unlock(&ng_nodelist_mtx); \ 327 } while (0) 328 329 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 330 331 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook) 332 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node) 333 334 #define NG_FREE_HOOK(hook) do { FREE((hook), M_NETGRAPH_HOOK); } while (0) 335 #define NG_FREE_NODE(node) do { FREE((node), M_NETGRAPH_NODE); } while (0) 336 337 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 338 339 /* Set this to kdb_enter("X") to catch all errors as they occur */ 340 #ifndef TRAP_ERROR 341 #define TRAP_ERROR() 342 #endif 343 344 static ng_ID_t nextID = 1; 345 346 #ifdef INVARIANTS 347 #define CHECK_DATA_MBUF(m) do { \ 348 struct mbuf *n; \ 349 int total; \ 350 \ 351 M_ASSERTPKTHDR(m); \ 352 for (total = 0, n = (m); n != NULL; n = n->m_next) { \ 353 total += n->m_len; \ 354 if (n->m_nextpkt != NULL) \ 355 panic("%s: m_nextpkt", __func__); \ 356 } \ 357 \ 358 if ((m)->m_pkthdr.len != total) { \ 359 panic("%s: %d != %d", \ 360 __func__, (m)->m_pkthdr.len, total); \ 361 } \ 362 } while (0) 363 #else 364 #define CHECK_DATA_MBUF(m) 365 #endif 366 367 #define ERROUT(x) do { error = (x); goto done; } while (0) 368 369 /************************************************************************ 370 Parse type definitions for generic messages 371 ************************************************************************/ 372 373 /* Handy structure parse type defining macro */ 374 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \ 375 static const struct ng_parse_struct_field \ 376 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \ 377 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \ 378 &ng_parse_struct_type, \ 379 &ng_ ## lo ## _type_fields \ 380 } 381 382 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ()); 383 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ()); 384 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ()); 385 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ()); 386 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ()); 387 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ()); 388 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type)); 389 390 /* Get length of an array when the length is stored as a 32 bit 391 value immediately preceding the array -- as with struct namelist 392 and struct typelist. */ 393 static int 394 ng_generic_list_getLength(const struct ng_parse_type *type, 395 const u_char *start, const u_char *buf) 396 { 397 return *((const u_int32_t *)(buf - 4)); 398 } 399 400 /* Get length of the array of struct linkinfo inside a struct hooklist */ 401 static int 402 ng_generic_linkinfo_getLength(const struct ng_parse_type *type, 403 const u_char *start, const u_char *buf) 404 { 405 const struct hooklist *hl = (const struct hooklist *)start; 406 407 return hl->nodeinfo.hooks; 408 } 409 410 /* Array type for a variable length array of struct namelist */ 411 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = { 412 &ng_generic_nodeinfo_type, 413 &ng_generic_list_getLength 414 }; 415 static const struct ng_parse_type ng_generic_nodeinfoarray_type = { 416 &ng_parse_array_type, 417 &ng_nodeinfoarray_type_info 418 }; 419 420 /* Array type for a variable length array of struct typelist */ 421 static const struct ng_parse_array_info ng_typeinfoarray_type_info = { 422 &ng_generic_typeinfo_type, 423 &ng_generic_list_getLength 424 }; 425 static const struct ng_parse_type ng_generic_typeinfoarray_type = { 426 &ng_parse_array_type, 427 &ng_typeinfoarray_type_info 428 }; 429 430 /* Array type for array of struct linkinfo in struct hooklist */ 431 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = { 432 &ng_generic_linkinfo_type, 433 &ng_generic_linkinfo_getLength 434 }; 435 static const struct ng_parse_type ng_generic_linkinfo_array_type = { 436 &ng_parse_array_type, 437 &ng_generic_linkinfo_array_type_info 438 }; 439 440 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type)); 441 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST, 442 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type)); 443 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES, 444 (&ng_generic_nodeinfoarray_type)); 445 446 /* List of commands and how to convert arguments to/from ASCII */ 447 static const struct ng_cmdlist ng_generic_cmds[] = { 448 { 449 NGM_GENERIC_COOKIE, 450 NGM_SHUTDOWN, 451 "shutdown", 452 NULL, 453 NULL 454 }, 455 { 456 NGM_GENERIC_COOKIE, 457 NGM_MKPEER, 458 "mkpeer", 459 &ng_generic_mkpeer_type, 460 NULL 461 }, 462 { 463 NGM_GENERIC_COOKIE, 464 NGM_CONNECT, 465 "connect", 466 &ng_generic_connect_type, 467 NULL 468 }, 469 { 470 NGM_GENERIC_COOKIE, 471 NGM_NAME, 472 "name", 473 &ng_generic_name_type, 474 NULL 475 }, 476 { 477 NGM_GENERIC_COOKIE, 478 NGM_RMHOOK, 479 "rmhook", 480 &ng_generic_rmhook_type, 481 NULL 482 }, 483 { 484 NGM_GENERIC_COOKIE, 485 NGM_NODEINFO, 486 "nodeinfo", 487 NULL, 488 &ng_generic_nodeinfo_type 489 }, 490 { 491 NGM_GENERIC_COOKIE, 492 NGM_LISTHOOKS, 493 "listhooks", 494 NULL, 495 &ng_generic_hooklist_type 496 }, 497 { 498 NGM_GENERIC_COOKIE, 499 NGM_LISTNAMES, 500 "listnames", 501 NULL, 502 &ng_generic_listnodes_type /* same as NGM_LISTNODES */ 503 }, 504 { 505 NGM_GENERIC_COOKIE, 506 NGM_LISTNODES, 507 "listnodes", 508 NULL, 509 &ng_generic_listnodes_type 510 }, 511 { 512 NGM_GENERIC_COOKIE, 513 NGM_LISTTYPES, 514 "listtypes", 515 NULL, 516 &ng_generic_typeinfo_type 517 }, 518 { 519 NGM_GENERIC_COOKIE, 520 NGM_TEXT_CONFIG, 521 "textconfig", 522 NULL, 523 &ng_parse_string_type 524 }, 525 { 526 NGM_GENERIC_COOKIE, 527 NGM_TEXT_STATUS, 528 "textstatus", 529 NULL, 530 &ng_parse_string_type 531 }, 532 { 533 NGM_GENERIC_COOKIE, 534 NGM_ASCII2BINARY, 535 "ascii2binary", 536 &ng_parse_ng_mesg_type, 537 &ng_parse_ng_mesg_type 538 }, 539 { 540 NGM_GENERIC_COOKIE, 541 NGM_BINARY2ASCII, 542 "binary2ascii", 543 &ng_parse_ng_mesg_type, 544 &ng_parse_ng_mesg_type 545 }, 546 { 0 } 547 }; 548 549 /************************************************************************ 550 Node routines 551 ************************************************************************/ 552 553 /* 554 * Instantiate a node of the requested type 555 */ 556 int 557 ng_make_node(const char *typename, node_p *nodepp) 558 { 559 struct ng_type *type; 560 int error; 561 562 /* Check that the type makes sense */ 563 if (typename == NULL) { 564 TRAP_ERROR(); 565 return (EINVAL); 566 } 567 568 /* Locate the node type. If we fail we return. Do not try to load 569 * module. 570 */ 571 if ((type = ng_findtype(typename)) == NULL) 572 return (ENXIO); 573 574 /* 575 * If we have a constructor, then make the node and 576 * call the constructor to do type specific initialisation. 577 */ 578 if (type->constructor != NULL) { 579 if ((error = ng_make_node_common(type, nodepp)) == 0) { 580 if ((error = ((*type->constructor)(*nodepp)) != 0)) { 581 NG_NODE_UNREF(*nodepp); 582 } 583 } 584 } else { 585 /* 586 * Node has no constructor. We cannot ask for one 587 * to be made. It must be brought into existence by 588 * some external agency. The external agency should 589 * call ng_make_node_common() directly to get the 590 * netgraph part initialised. 591 */ 592 TRAP_ERROR(); 593 error = EINVAL; 594 } 595 return (error); 596 } 597 598 /* 599 * Generic node creation. Called by node initialisation for externally 600 * instantiated nodes (e.g. hardware, sockets, etc ). 601 * The returned node has a reference count of 1. 602 */ 603 int 604 ng_make_node_common(struct ng_type *type, node_p *nodepp) 605 { 606 node_p node; 607 608 /* Require the node type to have been already installed */ 609 if (ng_findtype(type->name) == NULL) { 610 TRAP_ERROR(); 611 return (EINVAL); 612 } 613 614 /* Make a node and try attach it to the type */ 615 NG_ALLOC_NODE(node); 616 if (node == NULL) { 617 TRAP_ERROR(); 618 return (ENOMEM); 619 } 620 node->nd_type = type; 621 NG_NODE_REF(node); /* note reference */ 622 type->refs++; 623 624 NG_QUEUE_LOCK_INIT(&node->nd_input_queue); 625 node->nd_input_queue.queue = NULL; 626 node->nd_input_queue.last = &node->nd_input_queue.queue; 627 node->nd_input_queue.q_flags = 0; 628 node->nd_input_queue.q_node = node; 629 630 /* Initialize hook list for new node */ 631 LIST_INIT(&node->nd_hooks); 632 633 /* Link us into the node linked list */ 634 mtx_lock(&ng_nodelist_mtx); 635 LIST_INSERT_HEAD(&ng_nodelist, node, nd_nodes); 636 mtx_unlock(&ng_nodelist_mtx); 637 638 639 /* get an ID and put us in the hash chain */ 640 mtx_lock(&ng_idhash_mtx); 641 for (;;) { /* wrap protection, even if silly */ 642 node_p node2 = NULL; 643 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */ 644 645 /* Is there a problem with the new number? */ 646 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */ 647 if ((node->nd_ID != 0) && (node2 == NULL)) { 648 break; 649 } 650 } 651 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)], 652 node, nd_idnodes); 653 mtx_unlock(&ng_idhash_mtx); 654 655 /* Done */ 656 *nodepp = node; 657 return (0); 658 } 659 660 /* 661 * Forceably start the shutdown process on a node. Either call 662 * its shutdown method, or do the default shutdown if there is 663 * no type-specific method. 664 * 665 * We can only be called from a shutdown message, so we know we have 666 * a writer lock, and therefore exclusive access. It also means 667 * that we should not be on the work queue, but we check anyhow. 668 * 669 * Persistent node types must have a type-specific method which 670 * allocates a new node in which case, this one is irretrievably going away, 671 * or cleans up anything it needs, and just makes the node valid again, 672 * in which case we allow the node to survive. 673 * 674 * XXX We need to think of how to tell a persistent node that we 675 * REALLY need to go away because the hardware has gone or we 676 * are rebooting.... etc. 677 */ 678 void 679 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3) 680 { 681 hook_p hook; 682 683 /* Check if it's already shutting down */ 684 if ((node->nd_flags & NGF_CLOSING) != 0) 685 return; 686 687 if (node == &ng_deadnode) { 688 printf ("shutdown called on deadnode\n"); 689 return; 690 } 691 692 /* Add an extra reference so it doesn't go away during this */ 693 NG_NODE_REF(node); 694 695 /* 696 * Mark it invalid so any newcomers know not to try use it 697 * Also add our own mark so we can't recurse 698 * note that NGF_INVALID does not do this as it's also set during 699 * creation 700 */ 701 node->nd_flags |= NGF_INVALID|NGF_CLOSING; 702 703 /* If node has its pre-shutdown method, then call it first*/ 704 if (node->nd_type && node->nd_type->close) 705 (*node->nd_type->close)(node); 706 707 /* Notify all remaining connected nodes to disconnect */ 708 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL) 709 ng_destroy_hook(hook); 710 711 /* 712 * Drain the input queue forceably. 713 * it has no hooks so what's it going to do, bleed on someone? 714 * Theoretically we came here from a queue entry that was added 715 * Just before the queue was closed, so it should be empty anyway. 716 * Also removes us from worklist if needed. 717 */ 718 ng_flush_input_queue(&node->nd_input_queue); 719 720 /* Ask the type if it has anything to do in this case */ 721 if (node->nd_type && node->nd_type->shutdown) { 722 (*node->nd_type->shutdown)(node); 723 if (NG_NODE_IS_VALID(node)) { 724 /* 725 * Well, blow me down if the node code hasn't declared 726 * that it doesn't want to die. 727 * Presumably it is a persistant node. 728 * If we REALLY want it to go away, 729 * e.g. hardware going away, 730 * Our caller should set NGF_REALLY_DIE in nd_flags. 731 */ 732 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING); 733 NG_NODE_UNREF(node); /* Assume they still have theirs */ 734 return; 735 } 736 } else { /* do the default thing */ 737 NG_NODE_UNREF(node); 738 } 739 740 ng_unname(node); /* basically a NOP these days */ 741 742 /* 743 * Remove extra reference, possibly the last 744 * Possible other holders of references may include 745 * timeout callouts, but theoretically the node's supposed to 746 * have cancelled them. Possibly hardware dependencies may 747 * force a driver to 'linger' with a reference. 748 */ 749 NG_NODE_UNREF(node); 750 } 751 752 /* 753 * Remove a reference to the node, possibly the last. 754 * deadnode always acts as it it were the last. 755 */ 756 int 757 ng_unref_node(node_p node) 758 { 759 int v; 760 761 if (node == &ng_deadnode) { 762 return (0); 763 } 764 765 do { 766 v = node->nd_refs - 1; 767 } while (! atomic_cmpset_int(&node->nd_refs, v + 1, v)); 768 769 if (v == 0) { /* we were the last */ 770 771 mtx_lock(&ng_nodelist_mtx); 772 node->nd_type->refs--; /* XXX maybe should get types lock? */ 773 LIST_REMOVE(node, nd_nodes); 774 mtx_unlock(&ng_nodelist_mtx); 775 776 mtx_lock(&ng_idhash_mtx); 777 LIST_REMOVE(node, nd_idnodes); 778 mtx_unlock(&ng_idhash_mtx); 779 780 mtx_destroy(&node->nd_input_queue.q_mtx); 781 NG_FREE_NODE(node); 782 } 783 return (v); 784 } 785 786 /************************************************************************ 787 Node ID handling 788 ************************************************************************/ 789 static node_p 790 ng_ID2noderef(ng_ID_t ID) 791 { 792 node_p node; 793 mtx_lock(&ng_idhash_mtx); 794 NG_IDHASH_FIND(ID, node); 795 if(node) 796 NG_NODE_REF(node); 797 mtx_unlock(&ng_idhash_mtx); 798 return(node); 799 } 800 801 ng_ID_t 802 ng_node2ID(node_p node) 803 { 804 return (node ? NG_NODE_ID(node) : 0); 805 } 806 807 /************************************************************************ 808 Node name handling 809 ************************************************************************/ 810 811 /* 812 * Assign a node a name. Once assigned, the name cannot be changed. 813 */ 814 int 815 ng_name_node(node_p node, const char *name) 816 { 817 int i; 818 node_p node2; 819 820 /* Check the name is valid */ 821 for (i = 0; i < NG_NODESIZ; i++) { 822 if (name[i] == '\0' || name[i] == '.' || name[i] == ':') 823 break; 824 } 825 if (i == 0 || name[i] != '\0') { 826 TRAP_ERROR(); 827 return (EINVAL); 828 } 829 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */ 830 TRAP_ERROR(); 831 return (EINVAL); 832 } 833 834 /* Check the name isn't already being used */ 835 if ((node2 = ng_name2noderef(node, name)) != NULL) { 836 NG_NODE_UNREF(node2); 837 TRAP_ERROR(); 838 return (EADDRINUSE); 839 } 840 841 /* copy it */ 842 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ); 843 844 return (0); 845 } 846 847 /* 848 * Find a node by absolute name. The name should NOT end with ':' 849 * The name "." means "this node" and "[xxx]" means "the node 850 * with ID (ie, at address) xxx". 851 * 852 * Returns the node if found, else NULL. 853 * Eventually should add something faster than a sequential search. 854 * Note it acquires a reference on the node so you can be sure it's still 855 * there. 856 */ 857 node_p 858 ng_name2noderef(node_p here, const char *name) 859 { 860 node_p node; 861 ng_ID_t temp; 862 863 /* "." means "this node" */ 864 if (strcmp(name, ".") == 0) { 865 NG_NODE_REF(here); 866 return(here); 867 } 868 869 /* Check for name-by-ID */ 870 if ((temp = ng_decodeidname(name)) != 0) { 871 return (ng_ID2noderef(temp)); 872 } 873 874 /* Find node by name */ 875 mtx_lock(&ng_nodelist_mtx); 876 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 877 if (NG_NODE_IS_VALID(node) 878 && NG_NODE_HAS_NAME(node) 879 && (strcmp(NG_NODE_NAME(node), name) == 0)) { 880 break; 881 } 882 } 883 if (node) 884 NG_NODE_REF(node); 885 mtx_unlock(&ng_nodelist_mtx); 886 return (node); 887 } 888 889 /* 890 * Decode an ID name, eg. "[f03034de]". Returns 0 if the 891 * string is not valid, otherwise returns the value. 892 */ 893 static ng_ID_t 894 ng_decodeidname(const char *name) 895 { 896 const int len = strlen(name); 897 char *eptr; 898 u_long val; 899 900 /* Check for proper length, brackets, no leading junk */ 901 if ((len < 3) 902 || (name[0] != '[') 903 || (name[len - 1] != ']') 904 || (!isxdigit(name[1]))) { 905 return ((ng_ID_t)0); 906 } 907 908 /* Decode number */ 909 val = strtoul(name + 1, &eptr, 16); 910 if ((eptr - name != len - 1) 911 || (val == ULONG_MAX) 912 || (val == 0)) { 913 return ((ng_ID_t)0); 914 } 915 return (ng_ID_t)val; 916 } 917 918 /* 919 * Remove a name from a node. This should only be called 920 * when shutting down and removing the node. 921 * IF we allow name changing this may be more resurrected. 922 */ 923 void 924 ng_unname(node_p node) 925 { 926 } 927 928 /************************************************************************ 929 Hook routines 930 Names are not optional. Hooks are always connected, except for a 931 brief moment within these routines. On invalidation or during creation 932 they are connected to the 'dead' hook. 933 ************************************************************************/ 934 935 /* 936 * Remove a hook reference 937 */ 938 void 939 ng_unref_hook(hook_p hook) 940 { 941 int v; 942 943 if (hook == &ng_deadhook) { 944 return; 945 } 946 do { 947 v = hook->hk_refs; 948 } while (! atomic_cmpset_int(&hook->hk_refs, v, v - 1)); 949 950 if (v == 1) { /* we were the last */ 951 if (_NG_HOOK_NODE(hook)) { /* it'll probably be ng_deadnode */ 952 _NG_NODE_UNREF((_NG_HOOK_NODE(hook))); 953 hook->hk_node = NULL; 954 } 955 NG_FREE_HOOK(hook); 956 } 957 } 958 959 /* 960 * Add an unconnected hook to a node. Only used internally. 961 * Assumes node is locked. (XXX not yet true ) 962 */ 963 static int 964 ng_add_hook(node_p node, const char *name, hook_p *hookp) 965 { 966 hook_p hook; 967 int error = 0; 968 969 /* Check that the given name is good */ 970 if (name == NULL) { 971 TRAP_ERROR(); 972 return (EINVAL); 973 } 974 if (ng_findhook(node, name) != NULL) { 975 TRAP_ERROR(); 976 return (EEXIST); 977 } 978 979 /* Allocate the hook and link it up */ 980 NG_ALLOC_HOOK(hook); 981 if (hook == NULL) { 982 TRAP_ERROR(); 983 return (ENOMEM); 984 } 985 hook->hk_refs = 1; /* add a reference for us to return */ 986 hook->hk_flags = HK_INVALID; 987 hook->hk_peer = &ng_deadhook; /* start off this way */ 988 hook->hk_node = node; 989 NG_NODE_REF(node); /* each hook counts as a reference */ 990 991 /* Set hook name */ 992 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ); 993 994 /* 995 * Check if the node type code has something to say about it 996 * If it fails, the unref of the hook will also unref the node. 997 */ 998 if (node->nd_type->newhook != NULL) { 999 if ((error = (*node->nd_type->newhook)(node, hook, name))) { 1000 NG_HOOK_UNREF(hook); /* this frees the hook */ 1001 return (error); 1002 } 1003 } 1004 /* 1005 * The 'type' agrees so far, so go ahead and link it in. 1006 * We'll ask again later when we actually connect the hooks. 1007 */ 1008 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1009 node->nd_numhooks++; 1010 NG_HOOK_REF(hook); /* one for the node */ 1011 1012 if (hookp) 1013 *hookp = hook; 1014 return (0); 1015 } 1016 1017 /* 1018 * Find a hook 1019 * 1020 * Node types may supply their own optimized routines for finding 1021 * hooks. If none is supplied, we just do a linear search. 1022 * XXX Possibly we should add a reference to the hook? 1023 */ 1024 hook_p 1025 ng_findhook(node_p node, const char *name) 1026 { 1027 hook_p hook; 1028 1029 if (node->nd_type->findhook != NULL) 1030 return (*node->nd_type->findhook)(node, name); 1031 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) { 1032 if (NG_HOOK_IS_VALID(hook) 1033 && (strcmp(NG_HOOK_NAME(hook), name) == 0)) 1034 return (hook); 1035 } 1036 return (NULL); 1037 } 1038 1039 /* 1040 * Destroy a hook 1041 * 1042 * As hooks are always attached, this really destroys two hooks. 1043 * The one given, and the one attached to it. Disconnect the hooks 1044 * from each other first. We reconnect the peer hook to the 'dead' 1045 * hook so that it can still exist after we depart. We then 1046 * send the peer its own destroy message. This ensures that we only 1047 * interact with the peer's structures when it is locked processing that 1048 * message. We hold a reference to the peer hook so we are guaranteed that 1049 * the peer hook and node are still going to exist until 1050 * we are finished there as the hook holds a ref on the node. 1051 * We run this same code again on the peer hook, but that time it is already 1052 * attached to the 'dead' hook. 1053 * 1054 * This routine is called at all stages of hook creation 1055 * on error detection and must be able to handle any such stage. 1056 */ 1057 void 1058 ng_destroy_hook(hook_p hook) 1059 { 1060 hook_p peer; 1061 node_p node; 1062 1063 if (hook == &ng_deadhook) { /* better safe than sorry */ 1064 printf("ng_destroy_hook called on deadhook\n"); 1065 return; 1066 } 1067 1068 /* 1069 * Protect divorce process with mutex, to avoid races on 1070 * simultaneous disconnect. 1071 */ 1072 mtx_lock(&ng_topo_mtx); 1073 1074 hook->hk_flags |= HK_INVALID; 1075 1076 peer = NG_HOOK_PEER(hook); 1077 node = NG_HOOK_NODE(hook); 1078 1079 if (peer && (peer != &ng_deadhook)) { 1080 /* 1081 * Set the peer to point to ng_deadhook 1082 * from this moment on we are effectively independent it. 1083 * send it an rmhook message of it's own. 1084 */ 1085 peer->hk_peer = &ng_deadhook; /* They no longer know us */ 1086 hook->hk_peer = &ng_deadhook; /* Nor us, them */ 1087 if (NG_HOOK_NODE(peer) == &ng_deadnode) { 1088 /* 1089 * If it's already divorced from a node, 1090 * just free it. 1091 */ 1092 mtx_unlock(&ng_topo_mtx); 1093 } else { 1094 mtx_unlock(&ng_topo_mtx); 1095 ng_rmhook_self(peer); /* Send it a surprise */ 1096 } 1097 NG_HOOK_UNREF(peer); /* account for peer link */ 1098 NG_HOOK_UNREF(hook); /* account for peer link */ 1099 } else 1100 mtx_unlock(&ng_topo_mtx); 1101 1102 mtx_assert(&ng_topo_mtx, MA_NOTOWNED); 1103 1104 /* 1105 * Remove the hook from the node's list to avoid possible recursion 1106 * in case the disconnection results in node shutdown. 1107 */ 1108 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */ 1109 return; 1110 } 1111 LIST_REMOVE(hook, hk_hooks); 1112 node->nd_numhooks--; 1113 if (node->nd_type->disconnect) { 1114 /* 1115 * The type handler may elect to destroy the node so don't 1116 * trust its existence after this point. (except 1117 * that we still hold a reference on it. (which we 1118 * inherrited from the hook we are destroying) 1119 */ 1120 (*node->nd_type->disconnect) (hook); 1121 } 1122 1123 /* 1124 * Note that because we will point to ng_deadnode, the original node 1125 * is not decremented automatically so we do that manually. 1126 */ 1127 _NG_HOOK_NODE(hook) = &ng_deadnode; 1128 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */ 1129 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */ 1130 } 1131 1132 /* 1133 * Take two hooks on a node and merge the connection so that the given node 1134 * is effectively bypassed. 1135 */ 1136 int 1137 ng_bypass(hook_p hook1, hook_p hook2) 1138 { 1139 if (hook1->hk_node != hook2->hk_node) { 1140 TRAP_ERROR(); 1141 return (EINVAL); 1142 } 1143 hook1->hk_peer->hk_peer = hook2->hk_peer; 1144 hook2->hk_peer->hk_peer = hook1->hk_peer; 1145 1146 hook1->hk_peer = &ng_deadhook; 1147 hook2->hk_peer = &ng_deadhook; 1148 1149 NG_HOOK_UNREF(hook1); 1150 NG_HOOK_UNREF(hook2); 1151 1152 /* XXX If we ever cache methods on hooks update them as well */ 1153 ng_destroy_hook(hook1); 1154 ng_destroy_hook(hook2); 1155 return (0); 1156 } 1157 1158 /* 1159 * Install a new netgraph type 1160 */ 1161 int 1162 ng_newtype(struct ng_type *tp) 1163 { 1164 const size_t namelen = strlen(tp->name); 1165 1166 /* Check version and type name fields */ 1167 if ((tp->version != NG_ABI_VERSION) 1168 || (namelen == 0) 1169 || (namelen >= NG_TYPESIZ)) { 1170 TRAP_ERROR(); 1171 if (tp->version != NG_ABI_VERSION) { 1172 printf("Netgraph: Node type rejected. ABI mismatch. Suggest recompile\n"); 1173 } 1174 return (EINVAL); 1175 } 1176 1177 /* Check for name collision */ 1178 if (ng_findtype(tp->name) != NULL) { 1179 TRAP_ERROR(); 1180 return (EEXIST); 1181 } 1182 1183 1184 /* Link in new type */ 1185 mtx_lock(&ng_typelist_mtx); 1186 LIST_INSERT_HEAD(&ng_typelist, tp, types); 1187 tp->refs = 1; /* first ref is linked list */ 1188 mtx_unlock(&ng_typelist_mtx); 1189 return (0); 1190 } 1191 1192 /* 1193 * unlink a netgraph type 1194 * If no examples exist 1195 */ 1196 int 1197 ng_rmtype(struct ng_type *tp) 1198 { 1199 /* Check for name collision */ 1200 if (tp->refs != 1) { 1201 TRAP_ERROR(); 1202 return (EBUSY); 1203 } 1204 1205 /* Unlink type */ 1206 mtx_lock(&ng_typelist_mtx); 1207 LIST_REMOVE(tp, types); 1208 mtx_unlock(&ng_typelist_mtx); 1209 return (0); 1210 } 1211 1212 /* 1213 * Look for a type of the name given 1214 */ 1215 struct ng_type * 1216 ng_findtype(const char *typename) 1217 { 1218 struct ng_type *type; 1219 1220 mtx_lock(&ng_typelist_mtx); 1221 LIST_FOREACH(type, &ng_typelist, types) { 1222 if (strcmp(type->name, typename) == 0) 1223 break; 1224 } 1225 mtx_unlock(&ng_typelist_mtx); 1226 return (type); 1227 } 1228 1229 /************************************************************************ 1230 Composite routines 1231 ************************************************************************/ 1232 /* 1233 * Connect two nodes using the specified hooks, using queued functions. 1234 */ 1235 static int 1236 ng_con_part3(node_p node, item_p item, hook_p hook) 1237 { 1238 int error = 0; 1239 1240 /* 1241 * When we run, we know that the node 'node' is locked for us. 1242 * Our caller has a reference on the hook. 1243 * Our caller has a reference on the node. 1244 * (In this case our caller is ng_apply_item() ). 1245 * The peer hook has a reference on the hook. 1246 * We are all set up except for the final call to the node, and 1247 * the clearing of the INVALID flag. 1248 */ 1249 if (NG_HOOK_NODE(hook) == &ng_deadnode) { 1250 /* 1251 * The node must have been freed again since we last visited 1252 * here. ng_destry_hook() has this effect but nothing else does. 1253 * We should just release our references and 1254 * free anything we can think of. 1255 * Since we know it's been destroyed, and it's our caller 1256 * that holds the references, just return. 1257 */ 1258 ERROUT(ENOENT); 1259 } 1260 if (hook->hk_node->nd_type->connect) { 1261 if ((error = (*hook->hk_node->nd_type->connect) (hook))) { 1262 ng_destroy_hook(hook); /* also zaps peer */ 1263 printf("failed in ng_con_part3()\n"); 1264 ERROUT(error); 1265 } 1266 } 1267 /* 1268 * XXX this is wrong for SMP. Possibly we need 1269 * to separate out 'create' and 'invalid' flags. 1270 * should only set flags on hooks we have locked under our node. 1271 */ 1272 hook->hk_flags &= ~HK_INVALID; 1273 done: 1274 NG_FREE_ITEM(item); 1275 return (error); 1276 } 1277 1278 static int 1279 ng_con_part2(node_p node, item_p item, hook_p hook) 1280 { 1281 hook_p peer; 1282 int error = 0; 1283 1284 /* 1285 * When we run, we know that the node 'node' is locked for us. 1286 * Our caller has a reference on the hook. 1287 * Our caller has a reference on the node. 1288 * (In this case our caller is ng_apply_item() ). 1289 * The peer hook has a reference on the hook. 1290 * our node pointer points to the 'dead' node. 1291 * First check the hook name is unique. 1292 * Should not happen because we checked before queueing this. 1293 */ 1294 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) { 1295 TRAP_ERROR(); 1296 ng_destroy_hook(hook); /* should destroy peer too */ 1297 printf("failed in ng_con_part2()\n"); 1298 ERROUT(EEXIST); 1299 } 1300 /* 1301 * Check if the node type code has something to say about it 1302 * If it fails, the unref of the hook will also unref the attached node, 1303 * however since that node is 'ng_deadnode' this will do nothing. 1304 * The peer hook will also be destroyed. 1305 */ 1306 if (node->nd_type->newhook != NULL) { 1307 if ((error = (*node->nd_type->newhook)(node, hook, 1308 hook->hk_name))) { 1309 ng_destroy_hook(hook); /* should destroy peer too */ 1310 printf("failed in ng_con_part2()\n"); 1311 ERROUT(error); 1312 } 1313 } 1314 1315 /* 1316 * The 'type' agrees so far, so go ahead and link it in. 1317 * We'll ask again later when we actually connect the hooks. 1318 */ 1319 hook->hk_node = node; /* just overwrite ng_deadnode */ 1320 NG_NODE_REF(node); /* each hook counts as a reference */ 1321 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1322 node->nd_numhooks++; 1323 NG_HOOK_REF(hook); /* one for the node */ 1324 1325 /* 1326 * We now have a symmetrical situation, where both hooks have been 1327 * linked to their nodes, the newhook methods have been called 1328 * And the references are all correct. The hooks are still marked 1329 * as invalid, as we have not called the 'connect' methods 1330 * yet. 1331 * We can call the local one immediately as we have the 1332 * node locked, but we need to queue the remote one. 1333 */ 1334 if (hook->hk_node->nd_type->connect) { 1335 if ((error = (*hook->hk_node->nd_type->connect) (hook))) { 1336 ng_destroy_hook(hook); /* also zaps peer */ 1337 printf("failed in ng_con_part2(A)\n"); 1338 ERROUT(error); 1339 } 1340 } 1341 1342 /* 1343 * Acquire topo mutex to avoid race with ng_destroy_hook(). 1344 */ 1345 mtx_lock(&ng_topo_mtx); 1346 peer = hook->hk_peer; 1347 if (peer == &ng_deadhook) { 1348 mtx_unlock(&ng_topo_mtx); 1349 printf("failed in ng_con_part2(B)\n"); 1350 ng_destroy_hook(hook); 1351 ERROUT(ENOENT); 1352 } 1353 mtx_unlock(&ng_topo_mtx); 1354 1355 if ((error = ng_send_fn2(peer->hk_node, peer, item, &ng_con_part3, 1356 NULL, 0, NG_REUSE_ITEM))) { 1357 printf("failed in ng_con_part2(C)\n"); 1358 ng_destroy_hook(hook); /* also zaps peer */ 1359 return (error); /* item was consumed. */ 1360 } 1361 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */ 1362 return (0); /* item was consumed. */ 1363 done: 1364 NG_FREE_ITEM(item); 1365 return (error); 1366 } 1367 1368 /* 1369 * Connect this node with another node. We assume that this node is 1370 * currently locked, as we are only called from an NGM_CONNECT message. 1371 */ 1372 static int 1373 ng_con_nodes(item_p item, node_p node, const char *name, 1374 node_p node2, const char *name2) 1375 { 1376 int error; 1377 hook_p hook; 1378 hook_p hook2; 1379 1380 if (ng_findhook(node2, name2) != NULL) { 1381 return(EEXIST); 1382 } 1383 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */ 1384 return (error); 1385 /* Allocate the other hook and link it up */ 1386 NG_ALLOC_HOOK(hook2); 1387 if (hook2 == NULL) { 1388 TRAP_ERROR(); 1389 ng_destroy_hook(hook); /* XXX check ref counts so far */ 1390 NG_HOOK_UNREF(hook); /* including our ref */ 1391 return (ENOMEM); 1392 } 1393 hook2->hk_refs = 1; /* start with a reference for us. */ 1394 hook2->hk_flags = HK_INVALID; 1395 hook2->hk_peer = hook; /* Link the two together */ 1396 hook->hk_peer = hook2; 1397 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/ 1398 NG_HOOK_REF(hook2); 1399 hook2->hk_node = &ng_deadnode; 1400 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ); 1401 1402 /* 1403 * Queue the function above. 1404 * Procesing continues in that function in the lock context of 1405 * the other node. 1406 */ 1407 if ((error = ng_send_fn2(node2, hook2, item, &ng_con_part2, NULL, 0, 1408 NG_NOFLAGS))) { 1409 printf("failed in ng_con_nodes(): %d\n", error); 1410 ng_destroy_hook(hook); /* also zaps peer */ 1411 } 1412 1413 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */ 1414 NG_HOOK_UNREF(hook2); 1415 return (error); 1416 } 1417 1418 /* 1419 * Make a peer and connect. 1420 * We assume that the local node is locked. 1421 * The new node probably doesn't need a lock until 1422 * it has a hook, because it cannot really have any work until then, 1423 * but we should think about it a bit more. 1424 * 1425 * The problem may come if the other node also fires up 1426 * some hardware or a timer or some other source of activation, 1427 * also it may already get a command msg via it's ID. 1428 * 1429 * We could use the same method as ng_con_nodes() but we'd have 1430 * to add ability to remove the node when failing. (Not hard, just 1431 * make arg1 point to the node to remove). 1432 * Unless of course we just ignore failure to connect and leave 1433 * an unconnected node? 1434 */ 1435 static int 1436 ng_mkpeer(node_p node, const char *name, const char *name2, char *type) 1437 { 1438 node_p node2; 1439 hook_p hook1, hook2; 1440 int error; 1441 1442 if ((error = ng_make_node(type, &node2))) { 1443 return (error); 1444 } 1445 1446 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */ 1447 ng_rmnode(node2, NULL, NULL, 0); 1448 return (error); 1449 } 1450 1451 if ((error = ng_add_hook(node2, name2, &hook2))) { 1452 ng_rmnode(node2, NULL, NULL, 0); 1453 ng_destroy_hook(hook1); 1454 NG_HOOK_UNREF(hook1); 1455 return (error); 1456 } 1457 1458 /* 1459 * Actually link the two hooks together. 1460 */ 1461 hook1->hk_peer = hook2; 1462 hook2->hk_peer = hook1; 1463 1464 /* Each hook is referenced by the other */ 1465 NG_HOOK_REF(hook1); 1466 NG_HOOK_REF(hook2); 1467 1468 /* Give each node the opportunity to veto the pending connection */ 1469 if (hook1->hk_node->nd_type->connect) { 1470 error = (*hook1->hk_node->nd_type->connect) (hook1); 1471 } 1472 1473 if ((error == 0) && hook2->hk_node->nd_type->connect) { 1474 error = (*hook2->hk_node->nd_type->connect) (hook2); 1475 1476 } 1477 1478 /* 1479 * drop the references we were holding on the two hooks. 1480 */ 1481 if (error) { 1482 ng_destroy_hook(hook2); /* also zaps hook1 */ 1483 ng_rmnode(node2, NULL, NULL, 0); 1484 } else { 1485 /* As a last act, allow the hooks to be used */ 1486 hook1->hk_flags &= ~HK_INVALID; 1487 hook2->hk_flags &= ~HK_INVALID; 1488 } 1489 NG_HOOK_UNREF(hook1); 1490 NG_HOOK_UNREF(hook2); 1491 return (error); 1492 } 1493 1494 /************************************************************************ 1495 Utility routines to send self messages 1496 ************************************************************************/ 1497 1498 /* Shut this node down as soon as everyone is clear of it */ 1499 /* Should add arg "immediately" to jump the queue */ 1500 int 1501 ng_rmnode_self(node_p node) 1502 { 1503 int error; 1504 1505 if (node == &ng_deadnode) 1506 return (0); 1507 node->nd_flags |= NGF_INVALID; 1508 if (node->nd_flags & NGF_CLOSING) 1509 return (0); 1510 1511 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0); 1512 return (error); 1513 } 1514 1515 static void 1516 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2) 1517 { 1518 ng_destroy_hook(hook); 1519 return ; 1520 } 1521 1522 int 1523 ng_rmhook_self(hook_p hook) 1524 { 1525 int error; 1526 node_p node = NG_HOOK_NODE(hook); 1527 1528 if (node == &ng_deadnode) 1529 return (0); 1530 1531 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0); 1532 return (error); 1533 } 1534 1535 /*********************************************************************** 1536 * Parse and verify a string of the form: <NODE:><PATH> 1537 * 1538 * Such a string can refer to a specific node or a specific hook 1539 * on a specific node, depending on how you look at it. In the 1540 * latter case, the PATH component must not end in a dot. 1541 * 1542 * Both <NODE:> and <PATH> are optional. The <PATH> is a string 1543 * of hook names separated by dots. This breaks out the original 1544 * string, setting *nodep to "NODE" (or NULL if none) and *pathp 1545 * to "PATH" (or NULL if degenerate). Also, *hookp will point to 1546 * the final hook component of <PATH>, if any, otherwise NULL. 1547 * 1548 * This returns -1 if the path is malformed. The char ** are optional. 1549 ***********************************************************************/ 1550 int 1551 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp) 1552 { 1553 char *node, *path, *hook; 1554 int k; 1555 1556 /* 1557 * Extract absolute NODE, if any 1558 */ 1559 for (path = addr; *path && *path != ':'; path++); 1560 if (*path) { 1561 node = addr; /* Here's the NODE */ 1562 *path++ = '\0'; /* Here's the PATH */ 1563 1564 /* Node name must not be empty */ 1565 if (!*node) 1566 return -1; 1567 1568 /* A name of "." is OK; otherwise '.' not allowed */ 1569 if (strcmp(node, ".") != 0) { 1570 for (k = 0; node[k]; k++) 1571 if (node[k] == '.') 1572 return -1; 1573 } 1574 } else { 1575 node = NULL; /* No absolute NODE */ 1576 path = addr; /* Here's the PATH */ 1577 } 1578 1579 /* Snoop for illegal characters in PATH */ 1580 for (k = 0; path[k]; k++) 1581 if (path[k] == ':') 1582 return -1; 1583 1584 /* Check for no repeated dots in PATH */ 1585 for (k = 0; path[k]; k++) 1586 if (path[k] == '.' && path[k + 1] == '.') 1587 return -1; 1588 1589 /* Remove extra (degenerate) dots from beginning or end of PATH */ 1590 if (path[0] == '.') 1591 path++; 1592 if (*path && path[strlen(path) - 1] == '.') 1593 path[strlen(path) - 1] = 0; 1594 1595 /* If PATH has a dot, then we're not talking about a hook */ 1596 if (*path) { 1597 for (hook = path, k = 0; path[k]; k++) 1598 if (path[k] == '.') { 1599 hook = NULL; 1600 break; 1601 } 1602 } else 1603 path = hook = NULL; 1604 1605 /* Done */ 1606 if (nodep) 1607 *nodep = node; 1608 if (pathp) 1609 *pathp = path; 1610 if (hookp) 1611 *hookp = hook; 1612 return (0); 1613 } 1614 1615 /* 1616 * Given a path, which may be absolute or relative, and a starting node, 1617 * return the destination node. 1618 */ 1619 int 1620 ng_path2noderef(node_p here, const char *address, 1621 node_p *destp, hook_p *lasthook) 1622 { 1623 char fullpath[NG_PATHSIZ]; 1624 char *nodename, *path, pbuf[2]; 1625 node_p node, oldnode; 1626 char *cp; 1627 hook_p hook = NULL; 1628 1629 /* Initialize */ 1630 if (destp == NULL) { 1631 TRAP_ERROR(); 1632 return EINVAL; 1633 } 1634 *destp = NULL; 1635 1636 /* Make a writable copy of address for ng_path_parse() */ 1637 strncpy(fullpath, address, sizeof(fullpath) - 1); 1638 fullpath[sizeof(fullpath) - 1] = '\0'; 1639 1640 /* Parse out node and sequence of hooks */ 1641 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) { 1642 TRAP_ERROR(); 1643 return EINVAL; 1644 } 1645 if (path == NULL) { 1646 pbuf[0] = '.'; /* Needs to be writable */ 1647 pbuf[1] = '\0'; 1648 path = pbuf; 1649 } 1650 1651 /* 1652 * For an absolute address, jump to the starting node. 1653 * Note that this holds a reference on the node for us. 1654 * Don't forget to drop the reference if we don't need it. 1655 */ 1656 if (nodename) { 1657 node = ng_name2noderef(here, nodename); 1658 if (node == NULL) { 1659 TRAP_ERROR(); 1660 return (ENOENT); 1661 } 1662 } else { 1663 if (here == NULL) { 1664 TRAP_ERROR(); 1665 return (EINVAL); 1666 } 1667 node = here; 1668 NG_NODE_REF(node); 1669 } 1670 1671 /* 1672 * Now follow the sequence of hooks 1673 * XXX 1674 * We actually cannot guarantee that the sequence 1675 * is not being demolished as we crawl along it 1676 * without extra-ordinary locking etc. 1677 * So this is a bit dodgy to say the least. 1678 * We can probably hold up some things by holding 1679 * the nodelist mutex for the time of this 1680 * crawl if we wanted.. At least that way we wouldn't have to 1681 * worry about the nodes disappearing, but the hooks would still 1682 * be a problem. 1683 */ 1684 for (cp = path; node != NULL && *cp != '\0'; ) { 1685 char *segment; 1686 1687 /* 1688 * Break out the next path segment. Replace the dot we just 1689 * found with a NUL; "cp" points to the next segment (or the 1690 * NUL at the end). 1691 */ 1692 for (segment = cp; *cp != '\0'; cp++) { 1693 if (*cp == '.') { 1694 *cp++ = '\0'; 1695 break; 1696 } 1697 } 1698 1699 /* Empty segment */ 1700 if (*segment == '\0') 1701 continue; 1702 1703 /* We have a segment, so look for a hook by that name */ 1704 hook = ng_findhook(node, segment); 1705 1706 /* Can't get there from here... */ 1707 if (hook == NULL 1708 || NG_HOOK_PEER(hook) == NULL 1709 || NG_HOOK_NOT_VALID(hook) 1710 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) { 1711 TRAP_ERROR(); 1712 NG_NODE_UNREF(node); 1713 #if 0 1714 printf("hooknotvalid %s %s %d %d %d %d ", 1715 path, 1716 segment, 1717 hook == NULL, 1718 NG_HOOK_PEER(hook) == NULL, 1719 NG_HOOK_NOT_VALID(hook), 1720 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))); 1721 #endif 1722 return (ENOENT); 1723 } 1724 1725 /* 1726 * Hop on over to the next node 1727 * XXX 1728 * Big race conditions here as hooks and nodes go away 1729 * *** Idea.. store an ng_ID_t in each hook and use that 1730 * instead of the direct hook in this crawl? 1731 */ 1732 oldnode = node; 1733 if ((node = NG_PEER_NODE(hook))) 1734 NG_NODE_REF(node); /* XXX RACE */ 1735 NG_NODE_UNREF(oldnode); /* XXX another race */ 1736 if (NG_NODE_NOT_VALID(node)) { 1737 NG_NODE_UNREF(node); /* XXX more races */ 1738 node = NULL; 1739 } 1740 } 1741 1742 /* If node somehow missing, fail here (probably this is not needed) */ 1743 if (node == NULL) { 1744 TRAP_ERROR(); 1745 return (ENXIO); 1746 } 1747 1748 /* Done */ 1749 *destp = node; 1750 if (lasthook != NULL) 1751 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL); 1752 return (0); 1753 } 1754 1755 /***************************************************************\ 1756 * Input queue handling. 1757 * All activities are submitted to the node via the input queue 1758 * which implements a multiple-reader/single-writer gate. 1759 * Items which cannot be handled immediately are queued. 1760 * 1761 * read-write queue locking inline functions * 1762 \***************************************************************/ 1763 1764 static __inline item_p ng_dequeue(struct ng_queue * ngq, int *rw); 1765 static __inline item_p ng_acquire_read(struct ng_queue * ngq, 1766 item_p item); 1767 static __inline item_p ng_acquire_write(struct ng_queue * ngq, 1768 item_p item); 1769 static __inline void ng_leave_read(struct ng_queue * ngq); 1770 static __inline void ng_leave_write(struct ng_queue * ngq); 1771 static __inline void ng_queue_rw(struct ng_queue * ngq, 1772 item_p item, int rw); 1773 1774 /* 1775 * Definition of the bits fields in the ng_queue flag word. 1776 * Defined here rather than in netgraph.h because no-one should fiddle 1777 * with them. 1778 * 1779 * The ordering here may be important! don't shuffle these. 1780 */ 1781 /*- 1782 Safety Barrier--------+ (adjustable to suit taste) (not used yet) 1783 | 1784 V 1785 +-------+-------+-------+-------+-------+-------+-------+-------+ 1786 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1787 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |P|A| 1788 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |O|W| 1789 +-------+-------+-------+-------+-------+-------+-------+-------+ 1790 \___________________________ ____________________________/ | | 1791 V | | 1792 [active reader count] | | 1793 | | 1794 Operation Pending -------------------------------+ | 1795 | 1796 Active Writer ---------------------------------------+ 1797 1798 1799 */ 1800 #define WRITER_ACTIVE 0x00000001 1801 #define OP_PENDING 0x00000002 1802 #define READER_INCREMENT 0x00000004 1803 #define READER_MASK 0xfffffffc /* Not valid if WRITER_ACTIVE is set */ 1804 #define SAFETY_BARRIER 0x00100000 /* 128K items queued should be enough */ 1805 1806 /* Defines of more elaborate states on the queue */ 1807 /* Mask of bits a new read cares about */ 1808 #define NGQ_RMASK (WRITER_ACTIVE|OP_PENDING) 1809 1810 /* Mask of bits a new write cares about */ 1811 #define NGQ_WMASK (NGQ_RMASK|READER_MASK) 1812 1813 /* Test to decide if there is something on the queue. */ 1814 #define QUEUE_ACTIVE(QP) ((QP)->q_flags & OP_PENDING) 1815 1816 /* How to decide what the next queued item is. */ 1817 #define HEAD_IS_READER(QP) NGI_QUEUED_READER((QP)->queue) 1818 #define HEAD_IS_WRITER(QP) NGI_QUEUED_WRITER((QP)->queue) /* notused */ 1819 1820 /* Read the status to decide if the next item on the queue can now run. */ 1821 #define QUEUED_READER_CAN_PROCEED(QP) \ 1822 (((QP)->q_flags & (NGQ_RMASK & ~OP_PENDING)) == 0) 1823 #define QUEUED_WRITER_CAN_PROCEED(QP) \ 1824 (((QP)->q_flags & (NGQ_WMASK & ~OP_PENDING)) == 0) 1825 1826 /* Is there a chance of getting ANY work off the queue? */ 1827 #define NEXT_QUEUED_ITEM_CAN_PROCEED(QP) \ 1828 (QUEUE_ACTIVE(QP) && \ 1829 ((HEAD_IS_READER(QP)) ? QUEUED_READER_CAN_PROCEED(QP) : \ 1830 QUEUED_WRITER_CAN_PROCEED(QP))) 1831 1832 1833 #define NGQRW_R 0 1834 #define NGQRW_W 1 1835 1836 /* 1837 * Taking into account the current state of the queue and node, possibly take 1838 * the next entry off the queue and return it. Return NULL if there was 1839 * nothing we could return, either because there really was nothing there, or 1840 * because the node was in a state where it cannot yet process the next item 1841 * on the queue. 1842 * 1843 * This MUST MUST MUST be called with the mutex held. 1844 */ 1845 static __inline item_p 1846 ng_dequeue(struct ng_queue *ngq, int *rw) 1847 { 1848 item_p item; 1849 u_int add_arg; 1850 1851 mtx_assert(&ngq->q_mtx, MA_OWNED); 1852 /* 1853 * If there is nothing queued, then just return. 1854 * No point in continuing. 1855 * XXXGL: assert this? 1856 */ 1857 if (!QUEUE_ACTIVE(ngq)) { 1858 CTR4(KTR_NET, "%20s: node [%x] (%p) queue empty; " 1859 "queue flags 0x%lx", __func__, 1860 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1861 return (NULL); 1862 } 1863 1864 /* 1865 * From here, we can assume there is a head item. 1866 * We need to find out what it is and if it can be dequeued, given 1867 * the current state of the node. 1868 */ 1869 if (HEAD_IS_READER(ngq)) { 1870 if (!QUEUED_READER_CAN_PROCEED(ngq)) { 1871 /* 1872 * It's a reader but we can't use it. 1873 * We are stalled so make sure we don't 1874 * get called again until something changes. 1875 */ 1876 ng_worklist_remove(ngq->q_node); 1877 CTR4(KTR_NET, "%20s: node [%x] (%p) queued reader " 1878 "can't proceed; queue flags 0x%lx", __func__, 1879 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1880 return (NULL); 1881 } 1882 /* 1883 * Head of queue is a reader and we have no write active. 1884 * We don't care how many readers are already active. 1885 * Add the correct increment for the reader count. 1886 */ 1887 add_arg = READER_INCREMENT; 1888 *rw = NGQRW_R; 1889 } else if (QUEUED_WRITER_CAN_PROCEED(ngq)) { 1890 /* 1891 * There is a pending write, no readers and no active writer. 1892 * This means we can go ahead with the pending writer. Note 1893 * the fact that we now have a writer, ready for when we take 1894 * it off the queue. 1895 * 1896 * We don't need to worry about a possible collision with the 1897 * fasttrack reader. 1898 * 1899 * The fasttrack thread may take a long time to discover that we 1900 * are running so we would have an inconsistent state in the 1901 * flags for a while. Since we ignore the reader count 1902 * entirely when the WRITER_ACTIVE flag is set, this should 1903 * not matter (in fact it is defined that way). If it tests 1904 * the flag before this operation, the OP_PENDING flag 1905 * will make it fail, and if it tests it later, the 1906 * WRITER_ACTIVE flag will do the same. If it is SO slow that 1907 * we have actually completed the operation, and neither flag 1908 * is set by the time that it tests the flags, then it is 1909 * actually ok for it to continue. If it completes and we've 1910 * finished and the read pending is set it still fails. 1911 * 1912 * So we can just ignore it, as long as we can ensure that the 1913 * transition from WRITE_PENDING state to the WRITER_ACTIVE 1914 * state is atomic. 1915 * 1916 * After failing, first it will be held back by the mutex, then 1917 * when it can proceed, it will queue its request, then it 1918 * would arrive at this function. Usually it will have to 1919 * leave empty handed because the ACTIVE WRITER bit will be 1920 * set. 1921 * 1922 * Adjust the flags for the new active writer. 1923 */ 1924 add_arg = WRITER_ACTIVE; 1925 *rw = NGQRW_W; 1926 /* 1927 * We want to write "active writer, no readers " Now go make 1928 * it true. In fact there may be a number in the readers 1929 * count but we know it is not true and will be fixed soon. 1930 * We will fix the flags for the next pending entry in a 1931 * moment. 1932 */ 1933 } else { 1934 /* 1935 * We can't dequeue anything.. return and say so. Probably we 1936 * have a write pending and the readers count is non zero. If 1937 * we got here because a reader hit us just at the wrong 1938 * moment with the fasttrack code, and put us in a strange 1939 * state, then it will be coming through in just a moment, 1940 * (just as soon as we release the mutex) and keep things 1941 * moving. 1942 * Make sure we remove ourselves from the work queue. It 1943 * would be a waste of effort to do all this again. 1944 */ 1945 ng_worklist_remove(ngq->q_node); 1946 CTR4(KTR_NET, "%20s: node [%x] (%p) can't dequeue anything; " 1947 "queue flags 0x%lx", __func__, 1948 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1949 return (NULL); 1950 } 1951 1952 /* 1953 * Now we dequeue the request (whatever it may be) and correct the 1954 * pending flags and the next and last pointers. 1955 */ 1956 item = ngq->queue; 1957 ngq->queue = item->el_next; 1958 CTR6(KTR_NET, "%20s: node [%x] (%p) dequeued item %p with flags 0x%lx; " 1959 "queue flags 0x%lx", __func__, 1960 ngq->q_node->nd_ID,ngq->q_node, item, item->el_flags, ngq->q_flags); 1961 if (ngq->last == &(item->el_next)) { 1962 /* 1963 * that was the last entry in the queue so set the 'last 1964 * pointer up correctly and make sure the pending flag is 1965 * clear. 1966 */ 1967 add_arg += -OP_PENDING; 1968 ngq->last = &(ngq->queue); 1969 /* 1970 * Whatever flag was set will be cleared and 1971 * the new acive field will be set by the add as well, 1972 * so we don't need to change add_arg. 1973 * But we know we don't need to be on the work list. 1974 */ 1975 atomic_add_long(&ngq->q_flags, add_arg); 1976 ng_worklist_remove(ngq->q_node); 1977 } else { 1978 /* 1979 * Since there is still something on the queue 1980 * we don't need to change the PENDING flag. 1981 */ 1982 atomic_add_long(&ngq->q_flags, add_arg); 1983 /* 1984 * If we see more doable work, make sure we are 1985 * on the work queue. 1986 */ 1987 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) { 1988 ng_setisr(ngq->q_node); 1989 } 1990 } 1991 CTR6(KTR_NET, "%20s: node [%x] (%p) returning item %p as %s; " 1992 "queue flags 0x%lx", __func__, 1993 ngq->q_node->nd_ID, ngq->q_node, item, *rw ? "WRITER" : "READER" , 1994 ngq->q_flags); 1995 return (item); 1996 } 1997 1998 /* 1999 * Queue a packet to be picked up by someone else. 2000 * We really don't care who, but we can't or don't want to hang around 2001 * to process it ourselves. We are probably an interrupt routine.. 2002 * If the queue could be run, flag the netisr handler to start. 2003 */ 2004 static __inline void 2005 ng_queue_rw(struct ng_queue * ngq, item_p item, int rw) 2006 { 2007 mtx_assert(&ngq->q_mtx, MA_OWNED); 2008 2009 if (rw == NGQRW_W) 2010 NGI_SET_WRITER(item); 2011 else 2012 NGI_SET_READER(item); 2013 item->el_next = NULL; /* maybe not needed */ 2014 *ngq->last = item; 2015 CTR5(KTR_NET, "%20s: node [%x] (%p) queued item %p as %s", __func__, 2016 ngq->q_node->nd_ID, ngq->q_node, item, rw ? "WRITER" : "READER" ); 2017 /* 2018 * If it was the first item in the queue then we need to 2019 * set the last pointer and the type flags. 2020 */ 2021 if (ngq->last == &(ngq->queue)) { 2022 atomic_add_long(&ngq->q_flags, OP_PENDING); 2023 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__, 2024 ngq->q_node->nd_ID, ngq->q_node); 2025 } 2026 2027 ngq->last = &(item->el_next); 2028 /* 2029 * We can take the worklist lock with the node locked 2030 * BUT NOT THE REVERSE! 2031 */ 2032 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2033 ng_setisr(ngq->q_node); 2034 } 2035 2036 2037 /* 2038 * This function 'cheats' in that it first tries to 'grab' the use of the 2039 * node, without going through the mutex. We can do this becasue of the 2040 * semantics of the lock. The semantics include a clause that says that the 2041 * value of the readers count is invalid if the WRITER_ACTIVE flag is set. It 2042 * also says that the WRITER_ACTIVE flag cannot be set if the readers count 2043 * is not zero. Note that this talks about what is valid to SET the 2044 * WRITER_ACTIVE flag, because from the moment it is set, the value if the 2045 * reader count is immaterial, and not valid. The two 'pending' flags have a 2046 * similar effect, in that If they are orthogonal to the two active fields in 2047 * how they are set, but if either is set, the attempted 'grab' need to be 2048 * backed out because there is earlier work, and we maintain ordering in the 2049 * queue. The result of this is that the reader request can try obtain use of 2050 * the node with only a single atomic addition, and without any of the mutex 2051 * overhead. If this fails the operation degenerates to the same as for other 2052 * cases. 2053 * 2054 */ 2055 static __inline item_p 2056 ng_acquire_read(struct ng_queue *ngq, item_p item) 2057 { 2058 KASSERT(ngq != &ng_deadnode.nd_input_queue, 2059 ("%s: working on deadnode", __func__)); 2060 2061 /* ######### Hack alert ######### */ 2062 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 2063 if ((ngq->q_flags & NGQ_RMASK) == 0) { 2064 /* Successfully grabbed node */ 2065 CTR4(KTR_NET, "%20s: node [%x] (%p) fast acquired item %p", 2066 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2067 return (item); 2068 } 2069 /* undo the damage if we didn't succeed */ 2070 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 2071 2072 /* ######### End Hack alert ######### */ 2073 NG_QUEUE_LOCK(ngq); 2074 /* 2075 * Try again. Another processor (or interrupt for that matter) may 2076 * have removed the last queued item that was stopping us from 2077 * running, between the previous test, and the moment that we took 2078 * the mutex. (Or maybe a writer completed.) 2079 * Even if another fast-track reader hits during this period 2080 * we don't care as multiple readers is OK. 2081 */ 2082 if ((ngq->q_flags & NGQ_RMASK) == 0) { 2083 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 2084 NG_QUEUE_UNLOCK(ngq); 2085 CTR4(KTR_NET, "%20s: node [%x] (%p) slow acquired item %p", 2086 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2087 return (item); 2088 } 2089 2090 /* 2091 * and queue the request for later. 2092 */ 2093 ng_queue_rw(ngq, item, NGQRW_R); 2094 NG_QUEUE_UNLOCK(ngq); 2095 2096 return (NULL); 2097 } 2098 2099 static __inline item_p 2100 ng_acquire_write(struct ng_queue *ngq, item_p item) 2101 { 2102 KASSERT(ngq != &ng_deadnode.nd_input_queue, 2103 ("%s: working on deadnode", __func__)); 2104 2105 restart: 2106 NG_QUEUE_LOCK(ngq); 2107 /* 2108 * If there are no readers, no writer, and no pending packets, then 2109 * we can just go ahead. In all other situations we need to queue the 2110 * request 2111 */ 2112 if ((ngq->q_flags & NGQ_WMASK) == 0) { 2113 /* collision could happen *HERE* */ 2114 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE); 2115 NG_QUEUE_UNLOCK(ngq); 2116 if (ngq->q_flags & READER_MASK) { 2117 /* Collision with fast-track reader */ 2118 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2119 goto restart; 2120 } 2121 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p", 2122 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2123 return (item); 2124 } 2125 2126 /* 2127 * and queue the request for later. 2128 */ 2129 ng_queue_rw(ngq, item, NGQRW_W); 2130 NG_QUEUE_UNLOCK(ngq); 2131 2132 return (NULL); 2133 } 2134 2135 #if 0 2136 static __inline item_p 2137 ng_upgrade_write(struct ng_queue *ngq, item_p item) 2138 { 2139 KASSERT(ngq != &ng_deadnode.nd_input_queue, 2140 ("%s: working on deadnode", __func__)); 2141 2142 NGI_SET_WRITER(item); 2143 2144 mtx_lock_spin(&(ngq->q_mtx)); 2145 2146 /* 2147 * There will never be no readers as we are there ourselves. 2148 * Set the WRITER_ACTIVE flags ASAP to block out fast track readers. 2149 * The caller we are running from will call ng_leave_read() 2150 * soon, so we must account for that. We must leave again with the 2151 * READER lock. If we find other readers, then 2152 * queue the request for later. However "later" may be rignt now 2153 * if there are no readers. We don't really care if there are queued 2154 * items as we will bypass them anyhow. 2155 */ 2156 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE - READER_INCREMENT); 2157 if (ngq->q_flags & (NGQ_WMASK & ~OP_PENDING) == WRITER_ACTIVE) { 2158 mtx_unlock_spin(&(ngq->q_mtx)); 2159 2160 /* It's just us, act on the item. */ 2161 /* will NOT drop writer lock when done */ 2162 ng_apply_item(node, item, 0); 2163 2164 /* 2165 * Having acted on the item, atomically 2166 * down grade back to READER and finish up 2167 */ 2168 atomic_add_long(&ngq->q_flags, 2169 READER_INCREMENT - WRITER_ACTIVE); 2170 2171 /* Our caller will call ng_leave_read() */ 2172 return; 2173 } 2174 /* 2175 * It's not just us active, so queue us AT THE HEAD. 2176 * "Why?" I hear you ask. 2177 * Put us at the head of the queue as we've already been 2178 * through it once. If there is nothing else waiting, 2179 * set the correct flags. 2180 */ 2181 if ((item->el_next = ngq->queue) == NULL) { 2182 /* 2183 * Set up the "last" pointer. 2184 * We are the only (and thus last) item 2185 */ 2186 ngq->last = &(item->el_next); 2187 2188 /* We've gone from, 0 to 1 item in the queue */ 2189 atomic_add_long(&ngq->q_flags, OP_PENDING); 2190 2191 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__, 2192 ngq->q_node->nd_ID, ngq->q_node); 2193 }; 2194 ngq->queue = item; 2195 CTR5(KTR_NET, "%20s: node [%x] (%p) requeued item %p as WRITER", 2196 __func__, ngq->q_node->nd_ID, ngq->q_node, item ); 2197 2198 /* Reverse what we did above. That downgrades us back to reader */ 2199 atomic_add_long(&ngq->q_flags, READER_INCREMENT - WRITER_ACTIVE); 2200 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2201 ng_setisr(ngq->q_node); 2202 mtx_unlock_spin(&(ngq->q_mtx)); 2203 2204 return; 2205 } 2206 2207 #endif 2208 2209 static __inline void 2210 ng_leave_read(struct ng_queue *ngq) 2211 { 2212 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 2213 } 2214 2215 static __inline void 2216 ng_leave_write(struct ng_queue *ngq) 2217 { 2218 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2219 } 2220 2221 static void 2222 ng_flush_input_queue(struct ng_queue * ngq) 2223 { 2224 item_p item; 2225 2226 NG_QUEUE_LOCK(ngq); 2227 while (ngq->queue) { 2228 item = ngq->queue; 2229 ngq->queue = item->el_next; 2230 if (ngq->last == &(item->el_next)) { 2231 ngq->last = &(ngq->queue); 2232 atomic_add_long(&ngq->q_flags, -OP_PENDING); 2233 } 2234 NG_QUEUE_UNLOCK(ngq); 2235 2236 /* If the item is supplying a callback, call it with an error */ 2237 if (item->apply != NULL && 2238 refcount_release(&item->apply->refs)) { 2239 (*item->apply->apply)(item->apply->context, ENOENT); 2240 } 2241 NG_FREE_ITEM(item); 2242 NG_QUEUE_LOCK(ngq); 2243 } 2244 /* 2245 * Take us off the work queue if we are there. 2246 * We definately have no work to be done. 2247 */ 2248 ng_worklist_remove(ngq->q_node); 2249 NG_QUEUE_UNLOCK(ngq); 2250 } 2251 2252 /*********************************************************************** 2253 * Externally visible method for sending or queueing messages or data. 2254 ***********************************************************************/ 2255 2256 /* 2257 * The module code should have filled out the item correctly by this stage: 2258 * Common: 2259 * reference to destination node. 2260 * Reference to destination rcv hook if relevant. 2261 * apply pointer must be or NULL or reference valid struct ng_apply_info. 2262 * Data: 2263 * pointer to mbuf 2264 * Control_Message: 2265 * pointer to msg. 2266 * ID of original sender node. (return address) 2267 * Function: 2268 * Function pointer 2269 * void * argument 2270 * integer argument 2271 * 2272 * The nodes have several routines and macros to help with this task: 2273 */ 2274 2275 int 2276 ng_snd_item(item_p item, int flags) 2277 { 2278 hook_p hook; 2279 node_p node; 2280 int queue, rw; 2281 struct ng_queue *ngq; 2282 int error = 0; 2283 2284 /* We are sending item, so it must be present! */ 2285 KASSERT(item != NULL, ("ng_snd_item: item is NULL")); 2286 2287 #ifdef NETGRAPH_DEBUG 2288 _ngi_check(item, __FILE__, __LINE__); 2289 #endif 2290 2291 /* Item was sent once more, postpone apply() call. */ 2292 if (item->apply) 2293 refcount_acquire(&item->apply->refs); 2294 2295 node = NGI_NODE(item); 2296 /* Node is never optional. */ 2297 KASSERT(node != NULL, ("ng_snd_item: node is NULL")); 2298 2299 hook = NGI_HOOK(item); 2300 /* Valid hook and mbuf are mandatory for data. */ 2301 if ((item->el_flags & NGQF_TYPE) == NGQF_DATA) { 2302 KASSERT(hook != NULL, ("ng_snd_item: hook for data is NULL")); 2303 if (NGI_M(item) == NULL) 2304 ERROUT(EINVAL); 2305 CHECK_DATA_MBUF(NGI_M(item)); 2306 } 2307 2308 /* 2309 * If the item or the node specifies single threading, force 2310 * writer semantics. Similarly, the node may say one hook always 2311 * produces writers. These are overrides. 2312 */ 2313 if (((item->el_flags & NGQF_RW) == NGQRW_W) || 2314 (node->nd_flags & NGF_FORCE_WRITER) || 2315 (hook && (hook->hk_flags & HK_FORCE_WRITER))) { 2316 rw = NGQRW_W; 2317 } else { 2318 rw = NGQRW_R; 2319 } 2320 2321 /* 2322 * If sender or receiver requests queued delivery or stack usage 2323 * level is dangerous - enqueue message. 2324 */ 2325 if ((flags & NG_QUEUE) || (hook && (hook->hk_flags & HK_QUEUE))) { 2326 queue = 1; 2327 } else { 2328 queue = 0; 2329 #ifdef GET_STACK_USAGE 2330 /* 2331 * Most of netgraph nodes have small stack consumption and 2332 * for them 25% of free stack space is more than enough. 2333 * Nodes/hooks with higher stack usage should be marked as 2334 * HI_STACK. For them 50% of stack will be guaranteed then. 2335 * XXX: Values 25% and 50% are completely empirical. 2336 */ 2337 size_t st, su, sl; 2338 GET_STACK_USAGE(st, su); 2339 sl = st - su; 2340 if ((sl * 4 < st) || 2341 ((sl * 2 < st) && ((node->nd_flags & NGF_HI_STACK) || 2342 (hook && (hook->hk_flags & HK_HI_STACK))))) { 2343 queue = 1; 2344 } 2345 #endif 2346 } 2347 2348 ngq = &node->nd_input_queue; 2349 if (queue) { 2350 /* Put it on the queue for that node*/ 2351 #ifdef NETGRAPH_DEBUG 2352 _ngi_check(item, __FILE__, __LINE__); 2353 #endif 2354 NG_QUEUE_LOCK(ngq); 2355 ng_queue_rw(ngq, item, rw); 2356 NG_QUEUE_UNLOCK(ngq); 2357 2358 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0); 2359 } 2360 2361 /* 2362 * We already decided how we will be queueud or treated. 2363 * Try get the appropriate operating permission. 2364 */ 2365 if (rw == NGQRW_R) 2366 item = ng_acquire_read(ngq, item); 2367 else 2368 item = ng_acquire_write(ngq, item); 2369 2370 2371 /* Item was queued while trying to get permission. */ 2372 if (item == NULL) 2373 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0); 2374 2375 #ifdef NETGRAPH_DEBUG 2376 _ngi_check(item, __FILE__, __LINE__); 2377 #endif 2378 2379 NGI_GET_NODE(item, node); /* zaps stored node */ 2380 2381 error = ng_apply_item(node, item, rw); /* drops r/w lock when done */ 2382 2383 /* 2384 * If the node goes away when we remove the reference, 2385 * whatever we just did caused it.. whatever we do, DO NOT 2386 * access the node again! 2387 */ 2388 if (NG_NODE_UNREF(node) == 0) 2389 return (error); 2390 2391 NG_QUEUE_LOCK(ngq); 2392 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2393 ng_setisr(ngq->q_node); 2394 NG_QUEUE_UNLOCK(ngq); 2395 2396 return (error); 2397 2398 done: 2399 /* If was not sent, apply callback here. */ 2400 if (item->apply != NULL && refcount_release(&item->apply->refs)) 2401 (*item->apply->apply)(item->apply->context, error); 2402 2403 NG_FREE_ITEM(item); 2404 return (error); 2405 } 2406 2407 /* 2408 * We have an item that was possibly queued somewhere. 2409 * It should contain all the information needed 2410 * to run it on the appropriate node/hook. 2411 * If there is apply pointer and we own the last reference, call apply(). 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 struct ng_apply_info *apply; 2421 2422 /* Node and item are never optional. */ 2423 KASSERT(node != NULL, ("ng_apply_item: node is NULL")); 2424 KASSERT(item != NULL, ("ng_apply_item: item is NULL")); 2425 2426 NGI_GET_HOOK(item, hook); /* clears stored hook */ 2427 #ifdef NETGRAPH_DEBUG 2428 _ngi_check(item, __FILE__, __LINE__); 2429 #endif 2430 2431 apply = item->apply; 2432 2433 switch (item->el_flags & NGQF_TYPE) { 2434 case NGQF_DATA: 2435 /* 2436 * Check things are still ok as when we were queued. 2437 */ 2438 KASSERT(hook != NULL, ("ng_apply_item: hook for data is NULL")); 2439 if (NG_HOOK_NOT_VALID(hook) || 2440 NG_NODE_NOT_VALID(node)) { 2441 error = EIO; 2442 NG_FREE_ITEM(item); 2443 break; 2444 } 2445 /* 2446 * If no receive method, just silently drop it. 2447 * Give preference to the hook over-ride method 2448 */ 2449 if ((!(rcvdata = hook->hk_rcvdata)) 2450 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) { 2451 error = 0; 2452 NG_FREE_ITEM(item); 2453 break; 2454 } 2455 error = (*rcvdata)(hook, item); 2456 break; 2457 case NGQF_MESG: 2458 if (hook && NG_HOOK_NOT_VALID(hook)) { 2459 /* 2460 * The hook has been zapped then we can't use it. 2461 * Immediately drop its reference. 2462 * The message may not need it. 2463 */ 2464 NG_HOOK_UNREF(hook); 2465 hook = NULL; 2466 } 2467 /* 2468 * Similarly, if the node is a zombie there is 2469 * nothing we can do with it, drop everything. 2470 */ 2471 if (NG_NODE_NOT_VALID(node)) { 2472 TRAP_ERROR(); 2473 error = EINVAL; 2474 NG_FREE_ITEM(item); 2475 break; 2476 } 2477 /* 2478 * Call the appropriate message handler for the object. 2479 * It is up to the message handler to free the message. 2480 * If it's a generic message, handle it generically, 2481 * otherwise call the type's message handler (if it exists). 2482 * XXX (race). Remember that a queued message may 2483 * reference a node or hook that has just been 2484 * invalidated. It will exist as the queue code 2485 * is holding a reference, but.. 2486 */ 2487 if ((NGI_MSG(item)->header.typecookie == NGM_GENERIC_COOKIE) && 2488 ((NGI_MSG(item)->header.flags & NGF_RESP) == 0)) { 2489 error = ng_generic_msg(node, item, hook); 2490 break; 2491 } 2492 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) && 2493 (!(rcvmsg = node->nd_type->rcvmsg))) { 2494 TRAP_ERROR(); 2495 error = 0; 2496 NG_FREE_ITEM(item); 2497 break; 2498 } 2499 error = (*rcvmsg)(node, item, hook); 2500 break; 2501 case NGQF_FN: 2502 case NGQF_FN2: 2503 /* 2504 * We have to implicitly trust the hook, 2505 * as some of these are used for system purposes 2506 * where the hook is invalid. In the case of 2507 * the shutdown message we allow it to hit 2508 * even if the node is invalid. 2509 */ 2510 if ((NG_NODE_NOT_VALID(node)) 2511 && (NGI_FN(item) != &ng_rmnode)) { 2512 TRAP_ERROR(); 2513 error = EINVAL; 2514 NG_FREE_ITEM(item); 2515 break; 2516 } 2517 if ((item->el_flags & NGQF_TYPE) == NGQF_FN) { 2518 (*NGI_FN(item))(node, hook, NGI_ARG1(item), 2519 NGI_ARG2(item)); 2520 NG_FREE_ITEM(item); 2521 } else /* it is NGQF_FN2 */ 2522 error = (*NGI_FN2(item))(node, item, hook); 2523 break; 2524 } 2525 /* 2526 * We held references on some of the resources 2527 * that we took from the item. Now that we have 2528 * finished doing everything, drop those references. 2529 */ 2530 if (hook) 2531 NG_HOOK_UNREF(hook); 2532 2533 if (rw == NGQRW_R) 2534 ng_leave_read(&node->nd_input_queue); 2535 else 2536 ng_leave_write(&node->nd_input_queue); 2537 2538 /* Apply callback. */ 2539 if (apply != NULL && refcount_release(&apply->refs)) 2540 (*apply->apply)(apply->context, error); 2541 2542 return (error); 2543 } 2544 2545 /*********************************************************************** 2546 * Implement the 'generic' control messages 2547 ***********************************************************************/ 2548 static int 2549 ng_generic_msg(node_p here, item_p item, hook_p lasthook) 2550 { 2551 int error = 0; 2552 struct ng_mesg *msg; 2553 struct ng_mesg *resp = NULL; 2554 2555 NGI_GET_MSG(item, msg); 2556 if (msg->header.typecookie != NGM_GENERIC_COOKIE) { 2557 TRAP_ERROR(); 2558 error = EINVAL; 2559 goto out; 2560 } 2561 switch (msg->header.cmd) { 2562 case NGM_SHUTDOWN: 2563 ng_rmnode(here, NULL, NULL, 0); 2564 break; 2565 case NGM_MKPEER: 2566 { 2567 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data; 2568 2569 if (msg->header.arglen != sizeof(*mkp)) { 2570 TRAP_ERROR(); 2571 error = EINVAL; 2572 break; 2573 } 2574 mkp->type[sizeof(mkp->type) - 1] = '\0'; 2575 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0'; 2576 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0'; 2577 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type); 2578 break; 2579 } 2580 case NGM_CONNECT: 2581 { 2582 struct ngm_connect *const con = 2583 (struct ngm_connect *) msg->data; 2584 node_p node2; 2585 2586 if (msg->header.arglen != sizeof(*con)) { 2587 TRAP_ERROR(); 2588 error = EINVAL; 2589 break; 2590 } 2591 con->path[sizeof(con->path) - 1] = '\0'; 2592 con->ourhook[sizeof(con->ourhook) - 1] = '\0'; 2593 con->peerhook[sizeof(con->peerhook) - 1] = '\0'; 2594 /* Don't forget we get a reference.. */ 2595 error = ng_path2noderef(here, con->path, &node2, NULL); 2596 if (error) 2597 break; 2598 error = ng_con_nodes(item, here, con->ourhook, 2599 node2, con->peerhook); 2600 NG_NODE_UNREF(node2); 2601 break; 2602 } 2603 case NGM_NAME: 2604 { 2605 struct ngm_name *const nam = (struct ngm_name *) msg->data; 2606 2607 if (msg->header.arglen != sizeof(*nam)) { 2608 TRAP_ERROR(); 2609 error = EINVAL; 2610 break; 2611 } 2612 nam->name[sizeof(nam->name) - 1] = '\0'; 2613 error = ng_name_node(here, nam->name); 2614 break; 2615 } 2616 case NGM_RMHOOK: 2617 { 2618 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data; 2619 hook_p hook; 2620 2621 if (msg->header.arglen != sizeof(*rmh)) { 2622 TRAP_ERROR(); 2623 error = EINVAL; 2624 break; 2625 } 2626 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0'; 2627 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL) 2628 ng_destroy_hook(hook); 2629 break; 2630 } 2631 case NGM_NODEINFO: 2632 { 2633 struct nodeinfo *ni; 2634 2635 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT); 2636 if (resp == NULL) { 2637 error = ENOMEM; 2638 break; 2639 } 2640 2641 /* Fill in node info */ 2642 ni = (struct nodeinfo *) resp->data; 2643 if (NG_NODE_HAS_NAME(here)) 2644 strcpy(ni->name, NG_NODE_NAME(here)); 2645 strcpy(ni->type, here->nd_type->name); 2646 ni->id = ng_node2ID(here); 2647 ni->hooks = here->nd_numhooks; 2648 break; 2649 } 2650 case NGM_LISTHOOKS: 2651 { 2652 const int nhooks = here->nd_numhooks; 2653 struct hooklist *hl; 2654 struct nodeinfo *ni; 2655 hook_p hook; 2656 2657 /* Get response struct */ 2658 NG_MKRESPONSE(resp, msg, sizeof(*hl) 2659 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT); 2660 if (resp == NULL) { 2661 error = ENOMEM; 2662 break; 2663 } 2664 hl = (struct hooklist *) resp->data; 2665 ni = &hl->nodeinfo; 2666 2667 /* Fill in node info */ 2668 if (NG_NODE_HAS_NAME(here)) 2669 strcpy(ni->name, NG_NODE_NAME(here)); 2670 strcpy(ni->type, here->nd_type->name); 2671 ni->id = ng_node2ID(here); 2672 2673 /* Cycle through the linked list of hooks */ 2674 ni->hooks = 0; 2675 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) { 2676 struct linkinfo *const link = &hl->link[ni->hooks]; 2677 2678 if (ni->hooks >= nhooks) { 2679 log(LOG_ERR, "%s: number of %s changed\n", 2680 __func__, "hooks"); 2681 break; 2682 } 2683 if (NG_HOOK_NOT_VALID(hook)) 2684 continue; 2685 strcpy(link->ourhook, NG_HOOK_NAME(hook)); 2686 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook)); 2687 if (NG_PEER_NODE_NAME(hook)[0] != '\0') 2688 strcpy(link->nodeinfo.name, 2689 NG_PEER_NODE_NAME(hook)); 2690 strcpy(link->nodeinfo.type, 2691 NG_PEER_NODE(hook)->nd_type->name); 2692 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook)); 2693 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks; 2694 ni->hooks++; 2695 } 2696 break; 2697 } 2698 2699 case NGM_LISTNAMES: 2700 case NGM_LISTNODES: 2701 { 2702 const int unnamed = (msg->header.cmd == NGM_LISTNODES); 2703 struct namelist *nl; 2704 node_p node; 2705 int num = 0; 2706 2707 mtx_lock(&ng_nodelist_mtx); 2708 /* Count number of nodes */ 2709 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2710 if (NG_NODE_IS_VALID(node) 2711 && (unnamed || NG_NODE_HAS_NAME(node))) { 2712 num++; 2713 } 2714 } 2715 mtx_unlock(&ng_nodelist_mtx); 2716 2717 /* Get response struct */ 2718 NG_MKRESPONSE(resp, msg, sizeof(*nl) 2719 + (num * sizeof(struct nodeinfo)), M_NOWAIT); 2720 if (resp == NULL) { 2721 error = ENOMEM; 2722 break; 2723 } 2724 nl = (struct namelist *) resp->data; 2725 2726 /* Cycle through the linked list of nodes */ 2727 nl->numnames = 0; 2728 mtx_lock(&ng_nodelist_mtx); 2729 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2730 struct nodeinfo *const np = &nl->nodeinfo[nl->numnames]; 2731 2732 if (NG_NODE_NOT_VALID(node)) 2733 continue; 2734 if (!unnamed && (! NG_NODE_HAS_NAME(node))) 2735 continue; 2736 if (nl->numnames >= num) { 2737 log(LOG_ERR, "%s: number of %s changed\n", 2738 __func__, "nodes"); 2739 break; 2740 } 2741 if (NG_NODE_HAS_NAME(node)) 2742 strcpy(np->name, NG_NODE_NAME(node)); 2743 strcpy(np->type, node->nd_type->name); 2744 np->id = ng_node2ID(node); 2745 np->hooks = node->nd_numhooks; 2746 nl->numnames++; 2747 } 2748 mtx_unlock(&ng_nodelist_mtx); 2749 break; 2750 } 2751 2752 case NGM_LISTTYPES: 2753 { 2754 struct typelist *tl; 2755 struct ng_type *type; 2756 int num = 0; 2757 2758 mtx_lock(&ng_typelist_mtx); 2759 /* Count number of types */ 2760 LIST_FOREACH(type, &ng_typelist, types) { 2761 num++; 2762 } 2763 mtx_unlock(&ng_typelist_mtx); 2764 2765 /* Get response struct */ 2766 NG_MKRESPONSE(resp, msg, sizeof(*tl) 2767 + (num * sizeof(struct typeinfo)), M_NOWAIT); 2768 if (resp == NULL) { 2769 error = ENOMEM; 2770 break; 2771 } 2772 tl = (struct typelist *) resp->data; 2773 2774 /* Cycle through the linked list of types */ 2775 tl->numtypes = 0; 2776 mtx_lock(&ng_typelist_mtx); 2777 LIST_FOREACH(type, &ng_typelist, types) { 2778 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes]; 2779 2780 if (tl->numtypes >= num) { 2781 log(LOG_ERR, "%s: number of %s changed\n", 2782 __func__, "types"); 2783 break; 2784 } 2785 strcpy(tp->type_name, type->name); 2786 tp->numnodes = type->refs - 1; /* don't count list */ 2787 tl->numtypes++; 2788 } 2789 mtx_unlock(&ng_typelist_mtx); 2790 break; 2791 } 2792 2793 case NGM_BINARY2ASCII: 2794 { 2795 int bufSize = 20 * 1024; /* XXX hard coded constant */ 2796 const struct ng_parse_type *argstype; 2797 const struct ng_cmdlist *c; 2798 struct ng_mesg *binary, *ascii; 2799 2800 /* Data area must contain a valid netgraph message */ 2801 binary = (struct ng_mesg *)msg->data; 2802 if (msg->header.arglen < sizeof(struct ng_mesg) || 2803 (msg->header.arglen - sizeof(struct ng_mesg) < 2804 binary->header.arglen)) { 2805 TRAP_ERROR(); 2806 error = EINVAL; 2807 break; 2808 } 2809 2810 /* Get a response message with lots of room */ 2811 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT); 2812 if (resp == NULL) { 2813 error = ENOMEM; 2814 break; 2815 } 2816 ascii = (struct ng_mesg *)resp->data; 2817 2818 /* Copy binary message header to response message payload */ 2819 bcopy(binary, ascii, sizeof(*binary)); 2820 2821 /* Find command by matching typecookie and command number */ 2822 for (c = here->nd_type->cmdlist; 2823 c != NULL && c->name != NULL; c++) { 2824 if (binary->header.typecookie == c->cookie 2825 && binary->header.cmd == c->cmd) 2826 break; 2827 } 2828 if (c == NULL || c->name == NULL) { 2829 for (c = ng_generic_cmds; c->name != NULL; c++) { 2830 if (binary->header.typecookie == c->cookie 2831 && binary->header.cmd == c->cmd) 2832 break; 2833 } 2834 if (c->name == NULL) { 2835 NG_FREE_MSG(resp); 2836 error = ENOSYS; 2837 break; 2838 } 2839 } 2840 2841 /* Convert command name to ASCII */ 2842 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr), 2843 "%s", c->name); 2844 2845 /* Convert command arguments to ASCII */ 2846 argstype = (binary->header.flags & NGF_RESP) ? 2847 c->respType : c->mesgType; 2848 if (argstype == NULL) { 2849 *ascii->data = '\0'; 2850 } else { 2851 if ((error = ng_unparse(argstype, 2852 (u_char *)binary->data, 2853 ascii->data, bufSize)) != 0) { 2854 NG_FREE_MSG(resp); 2855 break; 2856 } 2857 } 2858 2859 /* Return the result as struct ng_mesg plus ASCII string */ 2860 bufSize = strlen(ascii->data) + 1; 2861 ascii->header.arglen = bufSize; 2862 resp->header.arglen = sizeof(*ascii) + bufSize; 2863 break; 2864 } 2865 2866 case NGM_ASCII2BINARY: 2867 { 2868 int bufSize = 2000; /* XXX hard coded constant */ 2869 const struct ng_cmdlist *c; 2870 const struct ng_parse_type *argstype; 2871 struct ng_mesg *ascii, *binary; 2872 int off = 0; 2873 2874 /* Data area must contain at least a struct ng_mesg + '\0' */ 2875 ascii = (struct ng_mesg *)msg->data; 2876 if ((msg->header.arglen < sizeof(*ascii) + 1) || 2877 (ascii->header.arglen < 1) || 2878 (msg->header.arglen < sizeof(*ascii) + 2879 ascii->header.arglen)) { 2880 TRAP_ERROR(); 2881 error = EINVAL; 2882 break; 2883 } 2884 ascii->data[ascii->header.arglen - 1] = '\0'; 2885 2886 /* Get a response message with lots of room */ 2887 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT); 2888 if (resp == NULL) { 2889 error = ENOMEM; 2890 break; 2891 } 2892 binary = (struct ng_mesg *)resp->data; 2893 2894 /* Copy ASCII message header to response message payload */ 2895 bcopy(ascii, binary, sizeof(*ascii)); 2896 2897 /* Find command by matching ASCII command string */ 2898 for (c = here->nd_type->cmdlist; 2899 c != NULL && c->name != NULL; c++) { 2900 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2901 break; 2902 } 2903 if (c == NULL || c->name == NULL) { 2904 for (c = ng_generic_cmds; c->name != NULL; c++) { 2905 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2906 break; 2907 } 2908 if (c->name == NULL) { 2909 NG_FREE_MSG(resp); 2910 error = ENOSYS; 2911 break; 2912 } 2913 } 2914 2915 /* Convert command name to binary */ 2916 binary->header.cmd = c->cmd; 2917 binary->header.typecookie = c->cookie; 2918 2919 /* Convert command arguments to binary */ 2920 argstype = (binary->header.flags & NGF_RESP) ? 2921 c->respType : c->mesgType; 2922 if (argstype == NULL) { 2923 bufSize = 0; 2924 } else { 2925 if ((error = ng_parse(argstype, ascii->data, 2926 &off, (u_char *)binary->data, &bufSize)) != 0) { 2927 NG_FREE_MSG(resp); 2928 break; 2929 } 2930 } 2931 2932 /* Return the result */ 2933 binary->header.arglen = bufSize; 2934 resp->header.arglen = sizeof(*binary) + bufSize; 2935 break; 2936 } 2937 2938 case NGM_TEXT_CONFIG: 2939 case NGM_TEXT_STATUS: 2940 /* 2941 * This one is tricky as it passes the command down to the 2942 * actual node, even though it is a generic type command. 2943 * This means we must assume that the item/msg is already freed 2944 * when control passes back to us. 2945 */ 2946 if (here->nd_type->rcvmsg != NULL) { 2947 NGI_MSG(item) = msg; /* put it back as we found it */ 2948 return((*here->nd_type->rcvmsg)(here, item, lasthook)); 2949 } 2950 /* Fall through if rcvmsg not supported */ 2951 default: 2952 TRAP_ERROR(); 2953 error = EINVAL; 2954 } 2955 /* 2956 * Sometimes a generic message may be statically allocated 2957 * to avoid problems with allocating when in tight memeory situations. 2958 * Don't free it if it is so. 2959 * I break them appart here, because erros may cause a free if the item 2960 * in which case we'd be doing it twice. 2961 * they are kept together above, to simplify freeing. 2962 */ 2963 out: 2964 NG_RESPOND_MSG(error, here, item, resp); 2965 if (msg) 2966 NG_FREE_MSG(msg); 2967 return (error); 2968 } 2969 2970 /************************************************************************ 2971 Queue element get/free routines 2972 ************************************************************************/ 2973 2974 uma_zone_t ng_qzone; 2975 static int maxalloc = 512; /* limit the damage of a leak */ 2976 2977 TUNABLE_INT("net.graph.maxalloc", &maxalloc); 2978 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc, 2979 0, "Maximum number of queue items to allocate"); 2980 2981 #ifdef NETGRAPH_DEBUG 2982 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist); 2983 static int allocated; /* number of items malloc'd */ 2984 #endif 2985 2986 /* 2987 * Get a queue entry. 2988 * This is usually called when a packet first enters netgraph. 2989 * By definition, this is usually from an interrupt, or from a user. 2990 * Users are not so important, but try be quick for the times that it's 2991 * an interrupt. 2992 */ 2993 static __inline item_p 2994 ng_getqblk(int flags) 2995 { 2996 item_p item = NULL; 2997 int wait; 2998 2999 wait = (flags & NG_WAITOK) ? M_WAITOK : M_NOWAIT; 3000 3001 item = uma_zalloc(ng_qzone, wait | M_ZERO); 3002 3003 #ifdef NETGRAPH_DEBUG 3004 if (item) { 3005 mtx_lock(&ngq_mtx); 3006 TAILQ_INSERT_TAIL(&ng_itemlist, item, all); 3007 allocated++; 3008 mtx_unlock(&ngq_mtx); 3009 } 3010 #endif 3011 3012 return (item); 3013 } 3014 3015 /* 3016 * Release a queue entry 3017 */ 3018 void 3019 ng_free_item(item_p item) 3020 { 3021 /* 3022 * The item may hold resources on it's own. We need to free 3023 * these before we can free the item. What they are depends upon 3024 * what kind of item it is. it is important that nodes zero 3025 * out pointers to resources that they remove from the item 3026 * or we release them again here. 3027 */ 3028 switch (item->el_flags & NGQF_TYPE) { 3029 case NGQF_DATA: 3030 /* If we have an mbuf still attached.. */ 3031 NG_FREE_M(_NGI_M(item)); 3032 break; 3033 case NGQF_MESG: 3034 _NGI_RETADDR(item) = 0; 3035 NG_FREE_MSG(_NGI_MSG(item)); 3036 break; 3037 case NGQF_FN: 3038 case NGQF_FN2: 3039 /* nothing to free really, */ 3040 _NGI_FN(item) = NULL; 3041 _NGI_ARG1(item) = NULL; 3042 _NGI_ARG2(item) = 0; 3043 break; 3044 } 3045 /* If we still have a node or hook referenced... */ 3046 _NGI_CLR_NODE(item); 3047 _NGI_CLR_HOOK(item); 3048 3049 #ifdef NETGRAPH_DEBUG 3050 mtx_lock(&ngq_mtx); 3051 TAILQ_REMOVE(&ng_itemlist, item, all); 3052 allocated--; 3053 mtx_unlock(&ngq_mtx); 3054 #endif 3055 uma_zfree(ng_qzone, item); 3056 } 3057 3058 /************************************************************************ 3059 Module routines 3060 ************************************************************************/ 3061 3062 /* 3063 * Handle the loading/unloading of a netgraph node type module 3064 */ 3065 int 3066 ng_mod_event(module_t mod, int event, void *data) 3067 { 3068 struct ng_type *const type = data; 3069 int s, error = 0; 3070 3071 switch (event) { 3072 case MOD_LOAD: 3073 3074 /* Register new netgraph node type */ 3075 s = splnet(); 3076 if ((error = ng_newtype(type)) != 0) { 3077 splx(s); 3078 break; 3079 } 3080 3081 /* Call type specific code */ 3082 if (type->mod_event != NULL) 3083 if ((error = (*type->mod_event)(mod, event, data))) { 3084 mtx_lock(&ng_typelist_mtx); 3085 type->refs--; /* undo it */ 3086 LIST_REMOVE(type, types); 3087 mtx_unlock(&ng_typelist_mtx); 3088 } 3089 splx(s); 3090 break; 3091 3092 case MOD_UNLOAD: 3093 s = splnet(); 3094 if (type->refs > 1) { /* make sure no nodes exist! */ 3095 error = EBUSY; 3096 } else { 3097 if (type->refs == 0) { 3098 /* failed load, nothing to undo */ 3099 splx(s); 3100 break; 3101 } 3102 if (type->mod_event != NULL) { /* check with type */ 3103 error = (*type->mod_event)(mod, event, data); 3104 if (error != 0) { /* type refuses.. */ 3105 splx(s); 3106 break; 3107 } 3108 } 3109 mtx_lock(&ng_typelist_mtx); 3110 LIST_REMOVE(type, types); 3111 mtx_unlock(&ng_typelist_mtx); 3112 } 3113 splx(s); 3114 break; 3115 3116 default: 3117 if (type->mod_event != NULL) 3118 error = (*type->mod_event)(mod, event, data); 3119 else 3120 error = EOPNOTSUPP; /* XXX ? */ 3121 break; 3122 } 3123 return (error); 3124 } 3125 3126 /* 3127 * Handle loading and unloading for this code. 3128 * The only thing we need to link into is the NETISR strucure. 3129 */ 3130 static int 3131 ngb_mod_event(module_t mod, int event, void *data) 3132 { 3133 int error = 0; 3134 3135 switch (event) { 3136 case MOD_LOAD: 3137 /* Initialize everything. */ 3138 NG_WORKLIST_LOCK_INIT(); 3139 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL, 3140 MTX_DEF); 3141 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL, 3142 MTX_DEF); 3143 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL, 3144 MTX_DEF); 3145 mtx_init(&ng_topo_mtx, "netgraph topology mutex", NULL, 3146 MTX_DEF); 3147 #ifdef NETGRAPH_DEBUG 3148 mtx_init(&ngq_mtx, "netgraph item list mutex", NULL, 3149 MTX_DEF); 3150 #endif 3151 ng_qzone = uma_zcreate("NetGraph items", sizeof(struct ng_item), 3152 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0); 3153 uma_zone_set_max(ng_qzone, maxalloc); 3154 netisr_register(NETISR_NETGRAPH, (netisr_t *)ngintr, NULL, 3155 NETISR_MPSAFE); 3156 break; 3157 case MOD_UNLOAD: 3158 /* You can't unload it because an interface may be using it. */ 3159 error = EBUSY; 3160 break; 3161 default: 3162 error = EOPNOTSUPP; 3163 break; 3164 } 3165 return (error); 3166 } 3167 3168 static moduledata_t netgraph_mod = { 3169 "netgraph", 3170 ngb_mod_event, 3171 (NULL) 3172 }; 3173 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_MIDDLE); 3174 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family"); 3175 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,""); 3176 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, ""); 3177 3178 #ifdef NETGRAPH_DEBUG 3179 void 3180 dumphook (hook_p hook, char *file, int line) 3181 { 3182 printf("hook: name %s, %d refs, Last touched:\n", 3183 _NG_HOOK_NAME(hook), hook->hk_refs); 3184 printf(" Last active @ %s, line %d\n", 3185 hook->lastfile, hook->lastline); 3186 if (line) { 3187 printf(" problem discovered at file %s, line %d\n", file, line); 3188 } 3189 } 3190 3191 void 3192 dumpnode(node_p node, char *file, int line) 3193 { 3194 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n", 3195 _NG_NODE_ID(node), node->nd_type->name, 3196 node->nd_numhooks, node->nd_flags, 3197 node->nd_refs, node->nd_name); 3198 printf(" Last active @ %s, line %d\n", 3199 node->lastfile, node->lastline); 3200 if (line) { 3201 printf(" problem discovered at file %s, line %d\n", file, line); 3202 } 3203 } 3204 3205 void 3206 dumpitem(item_p item, char *file, int line) 3207 { 3208 printf(" ACTIVE item, last used at %s, line %d", 3209 item->lastfile, item->lastline); 3210 switch(item->el_flags & NGQF_TYPE) { 3211 case NGQF_DATA: 3212 printf(" - [data]\n"); 3213 break; 3214 case NGQF_MESG: 3215 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item)); 3216 break; 3217 case NGQF_FN: 3218 printf(" - fn@%p (%p, %p, %p, %d (%x))\n", 3219 _NGI_FN(item), 3220 _NGI_NODE(item), 3221 _NGI_HOOK(item), 3222 item->body.fn.fn_arg1, 3223 item->body.fn.fn_arg2, 3224 item->body.fn.fn_arg2); 3225 break; 3226 case NGQF_FN2: 3227 printf(" - fn2@%p (%p, %p, %p, %d (%x))\n", 3228 _NGI_FN2(item), 3229 _NGI_NODE(item), 3230 _NGI_HOOK(item), 3231 item->body.fn.fn_arg1, 3232 item->body.fn.fn_arg2, 3233 item->body.fn.fn_arg2); 3234 break; 3235 } 3236 if (line) { 3237 printf(" problem discovered at file %s, line %d\n", file, line); 3238 if (_NGI_NODE(item)) { 3239 printf("node %p ([%x])\n", 3240 _NGI_NODE(item), ng_node2ID(_NGI_NODE(item))); 3241 } 3242 } 3243 } 3244 3245 static void 3246 ng_dumpitems(void) 3247 { 3248 item_p item; 3249 int i = 1; 3250 TAILQ_FOREACH(item, &ng_itemlist, all) { 3251 printf("[%d] ", i++); 3252 dumpitem(item, NULL, 0); 3253 } 3254 } 3255 3256 static void 3257 ng_dumpnodes(void) 3258 { 3259 node_p node; 3260 int i = 1; 3261 mtx_lock(&ng_nodelist_mtx); 3262 SLIST_FOREACH(node, &ng_allnodes, nd_all) { 3263 printf("[%d] ", i++); 3264 dumpnode(node, NULL, 0); 3265 } 3266 mtx_unlock(&ng_nodelist_mtx); 3267 } 3268 3269 static void 3270 ng_dumphooks(void) 3271 { 3272 hook_p hook; 3273 int i = 1; 3274 mtx_lock(&ng_nodelist_mtx); 3275 SLIST_FOREACH(hook, &ng_allhooks, hk_all) { 3276 printf("[%d] ", i++); 3277 dumphook(hook, NULL, 0); 3278 } 3279 mtx_unlock(&ng_nodelist_mtx); 3280 } 3281 3282 static int 3283 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS) 3284 { 3285 int error; 3286 int val; 3287 int i; 3288 3289 val = allocated; 3290 i = 1; 3291 error = sysctl_handle_int(oidp, &val, 0, req); 3292 if (error != 0 || req->newptr == NULL) 3293 return (error); 3294 if (val == 42) { 3295 ng_dumpitems(); 3296 ng_dumpnodes(); 3297 ng_dumphooks(); 3298 } 3299 return (0); 3300 } 3301 3302 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW, 3303 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items"); 3304 #endif /* NETGRAPH_DEBUG */ 3305 3306 3307 /*********************************************************************** 3308 * Worklist routines 3309 **********************************************************************/ 3310 /* NETISR thread enters here */ 3311 /* 3312 * Pick a node off the list of nodes with work, 3313 * try get an item to process off it. 3314 * If there are no more, remove the node from the list. 3315 */ 3316 static void 3317 ngintr(void) 3318 { 3319 item_p item; 3320 node_p node = NULL; 3321 3322 for (;;) { 3323 NG_WORKLIST_LOCK(); 3324 node = TAILQ_FIRST(&ng_worklist); 3325 if (!node) { 3326 NG_WORKLIST_UNLOCK(); 3327 break; 3328 } 3329 node->nd_flags &= ~NGF_WORKQ; 3330 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3331 NG_WORKLIST_UNLOCK(); 3332 CTR3(KTR_NET, "%20s: node [%x] (%p) taken off worklist", 3333 __func__, node->nd_ID, node); 3334 /* 3335 * We have the node. We also take over the reference 3336 * that the list had on it. 3337 * Now process as much as you can, until it won't 3338 * let you have another item off the queue. 3339 * All this time, keep the reference 3340 * that lets us be sure that the node still exists. 3341 * Let the reference go at the last minute. 3342 * ng_dequeue will put us back on the worklist 3343 * if there is more too do. This may be of use if there 3344 * are Multiple Processors and multiple Net threads in the 3345 * future. 3346 */ 3347 for (;;) { 3348 int rw; 3349 3350 NG_QUEUE_LOCK(&node->nd_input_queue); 3351 item = ng_dequeue(&node->nd_input_queue, &rw); 3352 if (item == NULL) { 3353 NG_QUEUE_UNLOCK(&node->nd_input_queue); 3354 break; /* go look for another node */ 3355 } else { 3356 NG_QUEUE_UNLOCK(&node->nd_input_queue); 3357 NGI_GET_NODE(item, node); /* zaps stored node */ 3358 ng_apply_item(node, item, rw); 3359 NG_NODE_UNREF(node); 3360 } 3361 } 3362 NG_NODE_UNREF(node); 3363 } 3364 } 3365 3366 static void 3367 ng_worklist_remove(node_p node) 3368 { 3369 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED); 3370 3371 NG_WORKLIST_LOCK(); 3372 if (node->nd_flags & NGF_WORKQ) { 3373 node->nd_flags &= ~NGF_WORKQ; 3374 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3375 NG_WORKLIST_UNLOCK(); 3376 NG_NODE_UNREF(node); 3377 CTR3(KTR_NET, "%20s: node [%x] (%p) removed from worklist", 3378 __func__, node->nd_ID, node); 3379 } else { 3380 NG_WORKLIST_UNLOCK(); 3381 } 3382 } 3383 3384 /* 3385 * XXX 3386 * It's posible that a debugging NG_NODE_REF may need 3387 * to be outside the mutex zone 3388 */ 3389 static void 3390 ng_setisr(node_p node) 3391 { 3392 3393 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED); 3394 3395 if ((node->nd_flags & NGF_WORKQ) == 0) { 3396 /* 3397 * If we are not already on the work queue, 3398 * then put us on. 3399 */ 3400 node->nd_flags |= NGF_WORKQ; 3401 NG_WORKLIST_LOCK(); 3402 TAILQ_INSERT_TAIL(&ng_worklist, node, nd_work); 3403 NG_WORKLIST_UNLOCK(); 3404 NG_NODE_REF(node); /* XXX fafe in mutex? */ 3405 CTR3(KTR_NET, "%20s: node [%x] (%p) put on worklist", __func__, 3406 node->nd_ID, node); 3407 } else 3408 CTR3(KTR_NET, "%20s: node [%x] (%p) already on worklist", 3409 __func__, node->nd_ID, node); 3410 schednetisr(NETISR_NETGRAPH); 3411 } 3412 3413 3414 /*********************************************************************** 3415 * Externally useable functions to set up a queue item ready for sending 3416 ***********************************************************************/ 3417 3418 #ifdef NETGRAPH_DEBUG 3419 #define ITEM_DEBUG_CHECKS \ 3420 do { \ 3421 if (NGI_NODE(item) ) { \ 3422 printf("item already has node"); \ 3423 kdb_enter(KDB_WHY_NETGRAPH, "has node"); \ 3424 NGI_CLR_NODE(item); \ 3425 } \ 3426 if (NGI_HOOK(item) ) { \ 3427 printf("item already has hook"); \ 3428 kdb_enter(KDB_WHY_NETGRAPH, "has hook"); \ 3429 NGI_CLR_HOOK(item); \ 3430 } \ 3431 } while (0) 3432 #else 3433 #define ITEM_DEBUG_CHECKS 3434 #endif 3435 3436 /* 3437 * Put mbuf into the item. 3438 * Hook and node references will be removed when the item is dequeued. 3439 * (or equivalent) 3440 * (XXX) Unsafe because no reference held by peer on remote node. 3441 * remote node might go away in this timescale. 3442 * We know the hooks can't go away because that would require getting 3443 * a writer item on both nodes and we must have at least a reader 3444 * here to be able to do this. 3445 * Note that the hook loaded is the REMOTE hook. 3446 * 3447 * This is possibly in the critical path for new data. 3448 */ 3449 item_p 3450 ng_package_data(struct mbuf *m, int flags) 3451 { 3452 item_p item; 3453 3454 if ((item = ng_getqblk(flags)) == NULL) { 3455 NG_FREE_M(m); 3456 return (NULL); 3457 } 3458 ITEM_DEBUG_CHECKS; 3459 item->el_flags = NGQF_DATA | NGQF_READER; 3460 NGI_M(item) = m; 3461 return (item); 3462 } 3463 3464 /* 3465 * Allocate a queue item and put items into it.. 3466 * Evaluate the address as this will be needed to queue it and 3467 * to work out what some of the fields should be. 3468 * Hook and node references will be removed when the item is dequeued. 3469 * (or equivalent) 3470 */ 3471 item_p 3472 ng_package_msg(struct ng_mesg *msg, int flags) 3473 { 3474 item_p item; 3475 3476 if ((item = ng_getqblk(flags)) == NULL) { 3477 NG_FREE_MSG(msg); 3478 return (NULL); 3479 } 3480 ITEM_DEBUG_CHECKS; 3481 /* Messages items count as writers unless explicitly exempted. */ 3482 if (msg->header.cmd & NGM_READONLY) 3483 item->el_flags = NGQF_MESG | NGQF_READER; 3484 else 3485 item->el_flags = NGQF_MESG | NGQF_WRITER; 3486 /* 3487 * Set the current lasthook into the queue item 3488 */ 3489 NGI_MSG(item) = msg; 3490 NGI_RETADDR(item) = 0; 3491 return (item); 3492 } 3493 3494 3495 3496 #define SET_RETADDR(item, here, retaddr) \ 3497 do { /* Data or fn items don't have retaddrs */ \ 3498 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \ 3499 if (retaddr) { \ 3500 NGI_RETADDR(item) = retaddr; \ 3501 } else { \ 3502 /* \ 3503 * The old return address should be ok. \ 3504 * If there isn't one, use the address \ 3505 * here. \ 3506 */ \ 3507 if (NGI_RETADDR(item) == 0) { \ 3508 NGI_RETADDR(item) \ 3509 = ng_node2ID(here); \ 3510 } \ 3511 } \ 3512 } \ 3513 } while (0) 3514 3515 int 3516 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr) 3517 { 3518 hook_p peer; 3519 node_p peernode; 3520 ITEM_DEBUG_CHECKS; 3521 /* 3522 * Quick sanity check.. 3523 * Since a hook holds a reference on it's node, once we know 3524 * that the peer is still connected (even if invalid,) we know 3525 * that the peer node is present, though maybe invalid. 3526 */ 3527 if ((hook == NULL) 3528 || NG_HOOK_NOT_VALID(hook) 3529 || (NG_HOOK_PEER(hook) == NULL) 3530 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)) 3531 || NG_NODE_NOT_VALID(NG_PEER_NODE(hook))) { 3532 NG_FREE_ITEM(item); 3533 TRAP_ERROR(); 3534 return (ENETDOWN); 3535 } 3536 3537 /* 3538 * Transfer our interest to the other (peer) end. 3539 */ 3540 peer = NG_HOOK_PEER(hook); 3541 NG_HOOK_REF(peer); 3542 NGI_SET_HOOK(item, peer); 3543 peernode = NG_PEER_NODE(hook); 3544 NG_NODE_REF(peernode); 3545 NGI_SET_NODE(item, peernode); 3546 SET_RETADDR(item, here, retaddr); 3547 return (0); 3548 } 3549 3550 int 3551 ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr) 3552 { 3553 node_p dest = NULL; 3554 hook_p hook = NULL; 3555 int error; 3556 3557 ITEM_DEBUG_CHECKS; 3558 /* 3559 * Note that ng_path2noderef increments the reference count 3560 * on the node for us if it finds one. So we don't have to. 3561 */ 3562 error = ng_path2noderef(here, address, &dest, &hook); 3563 if (error) { 3564 NG_FREE_ITEM(item); 3565 return (error); 3566 } 3567 NGI_SET_NODE(item, dest); 3568 if ( hook) { 3569 NG_HOOK_REF(hook); /* don't let it go while on the queue */ 3570 NGI_SET_HOOK(item, hook); 3571 } 3572 SET_RETADDR(item, here, retaddr); 3573 return (0); 3574 } 3575 3576 int 3577 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr) 3578 { 3579 node_p dest; 3580 3581 ITEM_DEBUG_CHECKS; 3582 /* 3583 * Find the target node. 3584 */ 3585 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */ 3586 if (dest == NULL) { 3587 NG_FREE_ITEM(item); 3588 TRAP_ERROR(); 3589 return(EINVAL); 3590 } 3591 /* Fill out the contents */ 3592 NGI_SET_NODE(item, dest); 3593 NGI_CLR_HOOK(item); 3594 SET_RETADDR(item, here, retaddr); 3595 return (0); 3596 } 3597 3598 /* 3599 * special case to send a message to self (e.g. destroy node) 3600 * Possibly indicate an arrival hook too. 3601 * Useful for removing that hook :-) 3602 */ 3603 item_p 3604 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg) 3605 { 3606 item_p item; 3607 3608 /* 3609 * Find the target node. 3610 * If there is a HOOK argument, then use that in preference 3611 * to the address. 3612 */ 3613 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL) { 3614 NG_FREE_MSG(msg); 3615 return (NULL); 3616 } 3617 3618 /* Fill out the contents */ 3619 item->el_flags = NGQF_MESG | NGQF_WRITER; 3620 NG_NODE_REF(here); 3621 NGI_SET_NODE(item, here); 3622 if (hook) { 3623 NG_HOOK_REF(hook); 3624 NGI_SET_HOOK(item, hook); 3625 } 3626 NGI_MSG(item) = msg; 3627 NGI_RETADDR(item) = ng_node2ID(here); 3628 return (item); 3629 } 3630 3631 /* 3632 * Send ng_item_fn function call to the specified node. 3633 */ 3634 3635 int 3636 ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2) 3637 { 3638 3639 return ng_send_fn1(node, hook, fn, arg1, arg2, NG_NOFLAGS); 3640 } 3641 3642 int 3643 ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2, 3644 int flags) 3645 { 3646 item_p item; 3647 3648 if ((item = ng_getqblk(flags)) == NULL) { 3649 return (ENOMEM); 3650 } 3651 item->el_flags = NGQF_FN | NGQF_WRITER; 3652 NG_NODE_REF(node); /* and one for the item */ 3653 NGI_SET_NODE(item, node); 3654 if (hook) { 3655 NG_HOOK_REF(hook); 3656 NGI_SET_HOOK(item, hook); 3657 } 3658 NGI_FN(item) = fn; 3659 NGI_ARG1(item) = arg1; 3660 NGI_ARG2(item) = arg2; 3661 return(ng_snd_item(item, flags)); 3662 } 3663 3664 /* 3665 * Send ng_item_fn2 function call to the specified node. 3666 * 3667 * If an optional pitem parameter is supplied, its apply 3668 * callback will be copied to the new item. If also NG_REUSE_ITEM 3669 * flag is set, no new item will be allocated, but pitem will 3670 * be used. 3671 */ 3672 int 3673 ng_send_fn2(node_p node, hook_p hook, item_p pitem, ng_item_fn2 *fn, void *arg1, 3674 int arg2, int flags) 3675 { 3676 item_p item; 3677 3678 KASSERT((pitem != NULL || (flags & NG_REUSE_ITEM) == 0), 3679 ("%s: NG_REUSE_ITEM but no pitem", __func__)); 3680 3681 /* 3682 * Allocate a new item if no supplied or 3683 * if we can't use supplied one. 3684 */ 3685 if (pitem == NULL || (flags & NG_REUSE_ITEM) == 0) { 3686 if ((item = ng_getqblk(flags)) == NULL) 3687 return (ENOMEM); 3688 } else 3689 item = pitem; 3690 3691 item->el_flags = NGQF_FN2 | NGQF_WRITER; 3692 NG_NODE_REF(node); /* and one for the item */ 3693 NGI_SET_NODE(item, node); 3694 if (hook) { 3695 NG_HOOK_REF(hook); 3696 NGI_SET_HOOK(item, hook); 3697 } 3698 NGI_FN2(item) = fn; 3699 NGI_ARG1(item) = arg1; 3700 NGI_ARG2(item) = arg2; 3701 if (pitem != NULL && (flags & NG_REUSE_ITEM) == 0) 3702 item->apply = pitem->apply; 3703 return(ng_snd_item(item, flags)); 3704 } 3705 3706 /* 3707 * Official timeout routines for Netgraph nodes. 3708 */ 3709 static void 3710 ng_callout_trampoline(void *arg) 3711 { 3712 item_p item = arg; 3713 3714 ng_snd_item(item, 0); 3715 } 3716 3717 3718 int 3719 ng_callout(struct callout *c, node_p node, hook_p hook, int ticks, 3720 ng_item_fn *fn, void * arg1, int arg2) 3721 { 3722 item_p item, oitem; 3723 3724 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL) 3725 return (ENOMEM); 3726 3727 item->el_flags = NGQF_FN | NGQF_WRITER; 3728 NG_NODE_REF(node); /* and one for the item */ 3729 NGI_SET_NODE(item, node); 3730 if (hook) { 3731 NG_HOOK_REF(hook); 3732 NGI_SET_HOOK(item, hook); 3733 } 3734 NGI_FN(item) = fn; 3735 NGI_ARG1(item) = arg1; 3736 NGI_ARG2(item) = arg2; 3737 oitem = c->c_arg; 3738 if (callout_reset(c, ticks, &ng_callout_trampoline, item) == 1 && 3739 oitem != NULL) 3740 NG_FREE_ITEM(oitem); 3741 return (0); 3742 } 3743 3744 /* A special modified version of untimeout() */ 3745 int 3746 ng_uncallout(struct callout *c, node_p node) 3747 { 3748 item_p item; 3749 int rval; 3750 3751 KASSERT(c != NULL, ("ng_uncallout: NULL callout")); 3752 KASSERT(node != NULL, ("ng_uncallout: NULL node")); 3753 3754 rval = callout_stop(c); 3755 item = c->c_arg; 3756 /* Do an extra check */ 3757 if ((rval > 0) && (c->c_func == &ng_callout_trampoline) && 3758 (NGI_NODE(item) == node)) { 3759 /* 3760 * We successfully removed it from the queue before it ran 3761 * So now we need to unreference everything that was 3762 * given extra references. (NG_FREE_ITEM does this). 3763 */ 3764 NG_FREE_ITEM(item); 3765 } 3766 c->c_arg = NULL; 3767 3768 return (rval); 3769 } 3770 3771 /* 3772 * Set the address, if none given, give the node here. 3773 */ 3774 void 3775 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr) 3776 { 3777 if (retaddr) { 3778 NGI_RETADDR(item) = retaddr; 3779 } else { 3780 /* 3781 * The old return address should be ok. 3782 * If there isn't one, use the address here. 3783 */ 3784 NGI_RETADDR(item) = ng_node2ID(here); 3785 } 3786 } 3787 3788 #define TESTING 3789 #ifdef TESTING 3790 /* just test all the macros */ 3791 void 3792 ng_macro_test(item_p item); 3793 void 3794 ng_macro_test(item_p item) 3795 { 3796 node_p node = NULL; 3797 hook_p hook = NULL; 3798 struct mbuf *m; 3799 struct ng_mesg *msg; 3800 ng_ID_t retaddr; 3801 int error; 3802 3803 NGI_GET_M(item, m); 3804 NGI_GET_MSG(item, msg); 3805 retaddr = NGI_RETADDR(item); 3806 NG_SEND_DATA(error, hook, m, NULL); 3807 NG_SEND_DATA_ONLY(error, hook, m); 3808 NG_FWD_NEW_DATA(error, item, hook, m); 3809 NG_FWD_ITEM_HOOK(error, item, hook); 3810 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr); 3811 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr); 3812 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr); 3813 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr); 3814 } 3815 #endif /* TESTING */ 3816 3817