1 /* 2 * ng_base.c 3 * 4 * Copyright (c) 1996-1999 Whistle Communications, Inc. 5 * All rights reserved. 6 * 7 * Subject to the following obligations and disclaimer of warranty, use and 8 * redistribution of this software, in source or object code forms, with or 9 * without modifications are expressly permitted by Whistle Communications; 10 * provided, however, that: 11 * 1. Any and all reproductions of the source or object code must include the 12 * copyright notice above and the following disclaimer of warranties; and 13 * 2. No rights are granted, in any manner or form, to use Whistle 14 * Communications, Inc. trademarks, including the mark "WHISTLE 15 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 16 * such appears in the above copyright notice or in the software. 17 * 18 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 19 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 20 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 21 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 22 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 23 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 24 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 25 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 26 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 27 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 28 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 29 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 30 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 31 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 32 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 33 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 34 * OF SUCH DAMAGE. 35 * 36 * Authors: Julian Elischer <julian@freebsd.org> 37 * Archie Cobbs <archie@freebsd.org> 38 * 39 * $FreeBSD$ 40 * $Whistle: ng_base.c,v 1.39 1999/01/28 23:54:53 julian Exp $ 41 */ 42 43 /* 44 * This file implements the base netgraph code. 45 */ 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/errno.h> 50 #include <sys/kernel.h> 51 #include <sys/malloc.h> 52 #include <sys/syslog.h> 53 #include <sys/sysctl.h> 54 #include <sys/linker.h> 55 #include <sys/queue.h> 56 #include <sys/mbuf.h> 57 #include <sys/ctype.h> 58 #include <sys/sysctl.h> 59 #include <machine/limits.h> 60 61 #include <net/netisr.h> 62 63 #include <netgraph/ng_message.h> 64 #include <netgraph/netgraph.h> 65 #include <netgraph/ng_parse.h> 66 67 MODULE_VERSION(netgraph, NG_ABI_VERSION); 68 69 /* List of all active nodes */ 70 static LIST_HEAD(, ng_node) ng_nodelist; 71 static struct mtx ng_nodelist_mtx; 72 73 #ifdef NETGRAPH_DEBUG 74 75 static SLIST_HEAD(, ng_node) ng_allnodes; 76 static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */ 77 static SLIST_HEAD(, ng_hook) ng_allhooks; 78 static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */ 79 80 static void ng_dumpitems(void); 81 static void ng_dumpnodes(void); 82 static void ng_dumphooks(void); 83 84 #endif /* NETGRAPH_DEBUG */ 85 /* 86 * DEAD versions of the structures. 87 * In order to avoid races, it is sometimes neccesary to point 88 * at SOMETHING even though theoretically, the current entity is 89 * INVALID. Use these to avoid these races. 90 */ 91 struct ng_type ng_deadtype = { 92 NG_ABI_VERSION, 93 "dead", 94 NULL, /* modevent */ 95 NULL, /* constructor */ 96 NULL, /* rcvmsg */ 97 NULL, /* shutdown */ 98 NULL, /* newhook */ 99 NULL, /* findhook */ 100 NULL, /* connect */ 101 NULL, /* rcvdata */ 102 NULL, /* disconnect */ 103 NULL, /* cmdlist */ 104 }; 105 106 struct ng_node ng_deadnode = { 107 "dead", 108 &ng_deadtype, 109 NG_INVALID, 110 1, /* refs */ 111 0, /* numhooks */ 112 NULL, /* private */ 113 0, /* ID */ 114 LIST_HEAD_INITIALIZER(ng_deadnode.hooks), 115 {}, /* all_nodes list entry */ 116 {}, /* id hashtable list entry */ 117 {}, /* workqueue entry */ 118 { 0, 119 {}, /* should never use! (should hang) */ 120 NULL, 121 &ng_deadnode.nd_input_queue.queue, 122 &ng_deadnode 123 }, 124 #ifdef NETGRAPH_DEBUG 125 ND_MAGIC, 126 __FILE__, 127 __LINE__, 128 {NULL} 129 #endif /* NETGRAPH_DEBUG */ 130 }; 131 132 struct ng_hook ng_deadhook = { 133 "dead", 134 NULL, /* private */ 135 HK_INVALID | HK_DEAD, 136 1, /* refs always >= 1 */ 137 &ng_deadhook, /* Peer is self */ 138 &ng_deadnode, /* attached to deadnode */ 139 {}, /* hooks list */ 140 NULL, /* override rcvmsg() */ 141 NULL, /* override rcvdata() */ 142 #ifdef NETGRAPH_DEBUG 143 HK_MAGIC, 144 __FILE__, 145 __LINE__, 146 {NULL} 147 #endif /* NETGRAPH_DEBUG */ 148 }; 149 150 /* 151 * END DEAD STRUCTURES 152 */ 153 /* List nodes with unallocated work */ 154 static TAILQ_HEAD(, ng_node) ng_worklist = TAILQ_HEAD_INITIALIZER(ng_worklist); 155 static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */ 156 157 /* List of installed types */ 158 static LIST_HEAD(, ng_type) ng_typelist; 159 static struct mtx ng_typelist_mtx; 160 161 /* Hash related definitions */ 162 /* XXX Don't need to initialise them because it's a LIST */ 163 #define NG_ID_HASH_SIZE 32 /* most systems wont need even this many */ 164 static LIST_HEAD(, ng_node) ng_ID_hash[NG_ID_HASH_SIZE]; 165 static struct mtx ng_idhash_mtx; 166 /* Method to find a node.. used twice so do it here */ 167 #define NG_IDHASH_FN(ID) ((ID) % (NG_ID_HASH_SIZE)) 168 #define NG_IDHASH_FIND(ID, node) \ 169 do { \ 170 LIST_FOREACH(node, &ng_ID_hash[NG_IDHASH_FN(ID)], \ 171 nd_idnodes) { \ 172 if (NG_NODE_IS_VALID(node) \ 173 && (NG_NODE_ID(node) == ID)) { \ 174 break; \ 175 } \ 176 } \ 177 } while (0) 178 179 /* Mutex that protects the free queue item list */ 180 static volatile item_p ngqfree; /* free ones */ 181 static struct mtx ngq_mtx; 182 183 /* Internal functions */ 184 static int ng_add_hook(node_p node, const char *name, hook_p * hookp); 185 static int ng_generic_msg(node_p here, item_p item, hook_p lasthook); 186 static ng_ID_t ng_decodeidname(const char *name); 187 static int ngb_mod_event(module_t mod, int event, void *data); 188 static void ng_worklist_remove(node_p node); 189 static void ngintr(void); 190 static int ng_apply_item(node_p node, item_p item); 191 static void ng_flush_input_queue(struct ng_queue * ngq); 192 static void ng_setisr(node_p node); 193 static node_p ng_ID2noderef(ng_ID_t ID); 194 static int ng_con_nodes(node_p node, const char *name, node_p node2, 195 const char *name2); 196 static void ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2); 197 static void ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2); 198 static int ng_mkpeer(node_p node, const char *name, 199 const char *name2, char *type); 200 201 /* imported , these used to be externally visible, some may go back */ 202 int ng_bypass(hook_p hook1, hook_p hook2); 203 void ng_destroy_hook(hook_p hook); 204 node_p ng_name2noderef(node_p node, const char *name); 205 int ng_path2noderef(node_p here, const char *path, 206 node_p *dest, hook_p *lasthook); 207 struct ng_type *ng_findtype(const char *type); 208 int ng_make_node(const char *type, node_p *nodepp); 209 int ng_path_parse(char *addr, char **node, char **path, char **hook); 210 void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3); 211 void ng_unname(node_p node); 212 213 214 /* Our own netgraph malloc type */ 215 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages"); 216 MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures"); 217 MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures"); 218 MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", "netgraph item structures"); 219 MALLOC_DEFINE(M_NETGRAPH_META, "netgraph_meta", "netgraph name storage"); 220 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage"); 221 222 /* Should not be visible outside this file */ 223 224 #define _NG_ALLOC_HOOK(hook) \ 225 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO) 226 #define _NG_ALLOC_NODE(node) \ 227 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO) 228 229 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/ 230 /* 231 * In debug mode: 232 * In an attempt to help track reference count screwups 233 * we do not free objects back to the malloc system, but keep them 234 * in a local cache where we can examine them and keep information safely 235 * after they have been freed. 236 * We use this scheme for nodes and hooks, and to some extent for items. 237 */ 238 static __inline hook_p 239 ng_alloc_hook(void) 240 { 241 hook_p hook; 242 SLIST_ENTRY(ng_hook) temp; 243 mtx_lock(&ng_nodelist_mtx); 244 hook = LIST_FIRST(&ng_freehooks); 245 if (hook) { 246 LIST_REMOVE(hook, hk_hooks); 247 bcopy(&hook->hk_all, &temp, sizeof(temp)); 248 bzero(hook, sizeof(struct ng_hook)); 249 bcopy(&temp, &hook->hk_all, sizeof(temp)); 250 mtx_unlock(&ng_nodelist_mtx); 251 hook->hk_magic = HK_MAGIC; 252 } else { 253 mtx_unlock(&ng_nodelist_mtx); 254 _NG_ALLOC_HOOK(hook); 255 if (hook) { 256 hook->hk_magic = HK_MAGIC; 257 mtx_lock(&ng_nodelist_mtx); 258 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all); 259 mtx_unlock(&ng_nodelist_mtx); 260 } 261 } 262 return (hook); 263 } 264 265 static __inline node_p 266 ng_alloc_node(void) 267 { 268 node_p node; 269 SLIST_ENTRY(ng_node) temp; 270 mtx_lock(&ng_nodelist_mtx); 271 node = LIST_FIRST(&ng_freenodes); 272 if (node) { 273 LIST_REMOVE(node, nd_nodes); 274 bcopy(&node->nd_all, &temp, sizeof(temp)); 275 bzero(node, sizeof(struct ng_node)); 276 bcopy(&temp, &node->nd_all, sizeof(temp)); 277 mtx_unlock(&ng_nodelist_mtx); 278 node->nd_magic = ND_MAGIC; 279 } else { 280 mtx_unlock(&ng_nodelist_mtx); 281 _NG_ALLOC_NODE(node); 282 if (node) { 283 node->nd_magic = ND_MAGIC; 284 mtx_lock(&ng_nodelist_mtx); 285 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all); 286 mtx_unlock(&ng_nodelist_mtx); 287 } 288 } 289 return (node); 290 } 291 292 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0) 293 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0) 294 295 296 #define NG_FREE_HOOK(hook) \ 297 do { \ 298 mtx_lock(&ng_nodelist_mtx); \ 299 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \ 300 hook->hk_magic = 0; \ 301 mtx_unlock(&ng_nodelist_mtx); \ 302 } while (0) 303 304 #define NG_FREE_NODE(node) \ 305 do { \ 306 mtx_lock(&ng_nodelist_mtx); \ 307 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \ 308 node->nd_magic = 0; \ 309 mtx_unlock(&ng_nodelist_mtx); \ 310 } while (0) 311 312 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 313 314 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook) 315 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node) 316 317 #define NG_FREE_HOOK(hook) do { FREE((hook), M_NETGRAPH_HOOK); } while (0) 318 #define NG_FREE_NODE(node) do { FREE((node), M_NETGRAPH_NODE); } while (0) 319 320 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 321 322 /* Warning: Generally use NG_FREE_ITEM() instead */ 323 #define NG_FREE_ITEM_REAL(item) do { FREE((item), M_NETGRAPH_ITEM); } while (0) 324 325 326 /* Set this to Debugger("X") to catch all errors as they occur */ 327 #ifndef TRAP_ERROR 328 #define TRAP_ERROR() 329 #endif 330 331 static ng_ID_t nextID = 1; 332 333 #ifdef INVARIANTS 334 #define CHECK_DATA_MBUF(m) do { \ 335 struct mbuf *n; \ 336 int total; \ 337 \ 338 if (((m)->m_flags & M_PKTHDR) == 0) \ 339 panic("%s: !PKTHDR", __func__); \ 340 for (total = 0, n = (m); n != NULL; n = n->m_next) \ 341 total += n->m_len; \ 342 if ((m)->m_pkthdr.len != total) { \ 343 panic("%s: %d != %d", \ 344 __func__, (m)->m_pkthdr.len, total); \ 345 } \ 346 } while (0) 347 #else 348 #define CHECK_DATA_MBUF(m) 349 #endif 350 351 352 /************************************************************************ 353 Parse type definitions for generic messages 354 ************************************************************************/ 355 356 /* Handy structure parse type defining macro */ 357 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \ 358 static const struct ng_parse_struct_field \ 359 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \ 360 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \ 361 &ng_parse_struct_type, \ 362 &ng_ ## lo ## _type_fields \ 363 } 364 365 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ()); 366 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ()); 367 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ()); 368 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ()); 369 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ()); 370 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ()); 371 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type)); 372 373 /* Get length of an array when the length is stored as a 32 bit 374 value immediately preceding the array -- as with struct namelist 375 and struct typelist. */ 376 static int 377 ng_generic_list_getLength(const struct ng_parse_type *type, 378 const u_char *start, const u_char *buf) 379 { 380 return *((const u_int32_t *)(buf - 4)); 381 } 382 383 /* Get length of the array of struct linkinfo inside a struct hooklist */ 384 static int 385 ng_generic_linkinfo_getLength(const struct ng_parse_type *type, 386 const u_char *start, const u_char *buf) 387 { 388 const struct hooklist *hl = (const struct hooklist *)start; 389 390 return hl->nodeinfo.hooks; 391 } 392 393 /* Array type for a variable length array of struct namelist */ 394 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = { 395 &ng_generic_nodeinfo_type, 396 &ng_generic_list_getLength 397 }; 398 static const struct ng_parse_type ng_generic_nodeinfoarray_type = { 399 &ng_parse_array_type, 400 &ng_nodeinfoarray_type_info 401 }; 402 403 /* Array type for a variable length array of struct typelist */ 404 static const struct ng_parse_array_info ng_typeinfoarray_type_info = { 405 &ng_generic_typeinfo_type, 406 &ng_generic_list_getLength 407 }; 408 static const struct ng_parse_type ng_generic_typeinfoarray_type = { 409 &ng_parse_array_type, 410 &ng_typeinfoarray_type_info 411 }; 412 413 /* Array type for array of struct linkinfo in struct hooklist */ 414 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = { 415 &ng_generic_linkinfo_type, 416 &ng_generic_linkinfo_getLength 417 }; 418 static const struct ng_parse_type ng_generic_linkinfo_array_type = { 419 &ng_parse_array_type, 420 &ng_generic_linkinfo_array_type_info 421 }; 422 423 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type)); 424 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST, 425 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type)); 426 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES, 427 (&ng_generic_nodeinfoarray_type)); 428 429 /* List of commands and how to convert arguments to/from ASCII */ 430 static const struct ng_cmdlist ng_generic_cmds[] = { 431 { 432 NGM_GENERIC_COOKIE, 433 NGM_SHUTDOWN, 434 "shutdown", 435 NULL, 436 NULL 437 }, 438 { 439 NGM_GENERIC_COOKIE, 440 NGM_MKPEER, 441 "mkpeer", 442 &ng_generic_mkpeer_type, 443 NULL 444 }, 445 { 446 NGM_GENERIC_COOKIE, 447 NGM_CONNECT, 448 "connect", 449 &ng_generic_connect_type, 450 NULL 451 }, 452 { 453 NGM_GENERIC_COOKIE, 454 NGM_NAME, 455 "name", 456 &ng_generic_name_type, 457 NULL 458 }, 459 { 460 NGM_GENERIC_COOKIE, 461 NGM_RMHOOK, 462 "rmhook", 463 &ng_generic_rmhook_type, 464 NULL 465 }, 466 { 467 NGM_GENERIC_COOKIE, 468 NGM_NODEINFO, 469 "nodeinfo", 470 NULL, 471 &ng_generic_nodeinfo_type 472 }, 473 { 474 NGM_GENERIC_COOKIE, 475 NGM_LISTHOOKS, 476 "listhooks", 477 NULL, 478 &ng_generic_hooklist_type 479 }, 480 { 481 NGM_GENERIC_COOKIE, 482 NGM_LISTNAMES, 483 "listnames", 484 NULL, 485 &ng_generic_listnodes_type /* same as NGM_LISTNODES */ 486 }, 487 { 488 NGM_GENERIC_COOKIE, 489 NGM_LISTNODES, 490 "listnodes", 491 NULL, 492 &ng_generic_listnodes_type 493 }, 494 { 495 NGM_GENERIC_COOKIE, 496 NGM_LISTTYPES, 497 "listtypes", 498 NULL, 499 &ng_generic_typeinfo_type 500 }, 501 { 502 NGM_GENERIC_COOKIE, 503 NGM_TEXT_CONFIG, 504 "textconfig", 505 NULL, 506 &ng_parse_string_type 507 }, 508 { 509 NGM_GENERIC_COOKIE, 510 NGM_TEXT_STATUS, 511 "textstatus", 512 NULL, 513 &ng_parse_string_type 514 }, 515 { 516 NGM_GENERIC_COOKIE, 517 NGM_ASCII2BINARY, 518 "ascii2binary", 519 &ng_parse_ng_mesg_type, 520 &ng_parse_ng_mesg_type 521 }, 522 { 523 NGM_GENERIC_COOKIE, 524 NGM_BINARY2ASCII, 525 "binary2ascii", 526 &ng_parse_ng_mesg_type, 527 &ng_parse_ng_mesg_type 528 }, 529 { 0 } 530 }; 531 532 /************************************************************************ 533 Node routines 534 ************************************************************************/ 535 536 /* 537 * Instantiate a node of the requested type 538 */ 539 int 540 ng_make_node(const char *typename, node_p *nodepp) 541 { 542 struct ng_type *type; 543 int error; 544 545 /* Check that the type makes sense */ 546 if (typename == NULL) { 547 TRAP_ERROR(); 548 return (EINVAL); 549 } 550 551 /* Locate the node type */ 552 if ((type = ng_findtype(typename)) == NULL) { 553 char filename[NG_TYPELEN + 4]; 554 linker_file_t lf; 555 int error; 556 557 /* Not found, try to load it as a loadable module */ 558 snprintf(filename, sizeof(filename), "ng_%s", typename); 559 error = linker_load_module(NULL, filename, NULL, NULL, &lf); 560 if (error != 0) 561 return (error); 562 lf->userrefs++; /* pretend loaded by the syscall */ 563 564 /* Try again, as now the type should have linked itself in */ 565 if ((type = ng_findtype(typename)) == NULL) 566 return (ENXIO); 567 } 568 569 /* 570 * If we have a constructor, then make the node and 571 * call the constructor to do type specific initialisation. 572 */ 573 if (type->constructor != NULL) { 574 if ((error = ng_make_node_common(type, nodepp)) == 0) { 575 if ((error = ((*type->constructor)(*nodepp)) != 0)) { 576 NG_NODE_UNREF(*nodepp); 577 } 578 } 579 } else { 580 /* 581 * Node has no constructor. We cannot ask for one 582 * to be made. It must be brought into existance by 583 * some external agency. The external agency should 584 * call ng_make_node_common() directly to get the 585 * netgraph part initialised. 586 */ 587 TRAP_ERROR(); 588 error = EINVAL; 589 } 590 return (error); 591 } 592 593 /* 594 * Generic node creation. Called by node initialisation for externally 595 * instantiated nodes (e.g. hardware, sockets, etc ). 596 * The returned node has a reference count of 1. 597 */ 598 int 599 ng_make_node_common(struct ng_type *type, node_p *nodepp) 600 { 601 node_p node; 602 603 /* Require the node type to have been already installed */ 604 if (ng_findtype(type->name) == NULL) { 605 TRAP_ERROR(); 606 return (EINVAL); 607 } 608 609 /* Make a node and try attach it to the type */ 610 NG_ALLOC_NODE(node); 611 if (node == NULL) { 612 TRAP_ERROR(); 613 return (ENOMEM); 614 } 615 node->nd_type = type; 616 NG_NODE_REF(node); /* note reference */ 617 type->refs++; 618 619 mtx_init(&node->nd_input_queue.q_mtx, "ng_node", NULL, MTX_SPIN); 620 node->nd_input_queue.queue = NULL; 621 node->nd_input_queue.last = &node->nd_input_queue.queue; 622 node->nd_input_queue.q_flags = 0; 623 node->nd_input_queue.q_node = node; 624 625 /* Initialize hook list for new node */ 626 LIST_INIT(&node->nd_hooks); 627 628 /* Link us into the node linked list */ 629 mtx_lock(&ng_nodelist_mtx); 630 LIST_INSERT_HEAD(&ng_nodelist, node, nd_nodes); 631 mtx_unlock(&ng_nodelist_mtx); 632 633 634 /* get an ID and put us in the hash chain */ 635 mtx_lock(&ng_idhash_mtx); 636 for (;;) { /* wrap protection, even if silly */ 637 node_p node2 = NULL; 638 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */ 639 640 /* Is there a problem with the new number? */ 641 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */ 642 if ((node->nd_ID != 0) && (node2 == NULL)) { 643 break; 644 } 645 } 646 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)], 647 node, nd_idnodes); 648 mtx_unlock(&ng_idhash_mtx); 649 650 /* Done */ 651 *nodepp = node; 652 return (0); 653 } 654 655 /* 656 * Forceably start the shutdown process on a node. Either call 657 * it's shutdown method, or do the default shutdown if there is 658 * no type-specific method. 659 * 660 * We can only be called form a shutdown message, so we know we have 661 * a writer lock, and therefore exclusive access. It also means 662 * that we should not be on the work queue, but we check anyhow. 663 * 664 * Persistent node types must have a type-specific method which 665 * Allocates a new node in which case, this one is irretrievably going away, 666 * or cleans up anything it needs, and just makes the node valid again, 667 * in which case we allow the node to survive. 668 * 669 * XXX We need to think of how to tell a persistant node that we 670 * REALLY need to go away because the hardware has gone or we 671 * are rebooting.... etc. 672 */ 673 void 674 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3) 675 { 676 hook_p hook; 677 678 /* Check if it's already shutting down */ 679 if ((node->nd_flags & NG_CLOSING) != 0) 680 return; 681 682 if (node == &ng_deadnode) { 683 printf ("shutdown called on deadnode\n"); 684 return; 685 } 686 687 /* Add an extra reference so it doesn't go away during this */ 688 NG_NODE_REF(node); 689 690 /* 691 * Mark it invalid so any newcomers know not to try use it 692 * Also add our own mark so we can't recurse 693 * note that NG_INVALID does not do this as it's also set during 694 * creation 695 */ 696 node->nd_flags |= NG_INVALID|NG_CLOSING; 697 698 /* Notify all remaining connected nodes to disconnect */ 699 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL) 700 ng_destroy_hook(hook); 701 702 /* 703 * Drain the input queue forceably. 704 * it has no hooks so what's it going to do, bleed on someone? 705 * Theoretically we came here from a queue entry that was added 706 * Just before the queue was closed, so it should be empty anyway. 707 * Also removes us from worklist if needed. 708 */ 709 ng_flush_input_queue(&node->nd_input_queue); 710 711 /* Ask the type if it has anything to do in this case */ 712 if (node->nd_type && node->nd_type->shutdown) { 713 (*node->nd_type->shutdown)(node); 714 if (NG_NODE_IS_VALID(node)) { 715 /* 716 * Well, blow me down if the node code hasn't declared 717 * that it doesn't want to die. 718 * Presumably it is a persistant node. 719 * If we REALLY want it to go away, 720 * e.g. hardware going away, 721 * Our caller should set NG_REALLY_DIE in nd_flags. 722 */ 723 node->nd_flags &= ~(NG_INVALID|NG_CLOSING); 724 NG_NODE_UNREF(node); /* Assume they still have theirs */ 725 return; 726 } 727 } else { /* do the default thing */ 728 NG_NODE_UNREF(node); 729 } 730 731 ng_unname(node); /* basically a NOP these days */ 732 733 /* 734 * Remove extra reference, possibly the last 735 * Possible other holders of references may include 736 * timeout callouts, but theoretically the node's supposed to 737 * have cancelled them. Possibly hardware dependencies may 738 * force a driver to 'linger' with a reference. 739 */ 740 NG_NODE_UNREF(node); 741 } 742 743 #ifdef NETGRAPH_DEBUG 744 void 745 ng_ref_node(node_p node) 746 { 747 _NG_NODE_REF(node); 748 } 749 #endif 750 751 /* 752 * Remove a reference to the node, possibly the last. 753 * deadnode always acts as it it were the last. 754 */ 755 int 756 ng_unref_node(node_p node) 757 { 758 int v; 759 760 if (node == &ng_deadnode) { 761 return (0); 762 } 763 764 do { 765 v = node->nd_refs - 1; 766 } while (! atomic_cmpset_int(&node->nd_refs, v + 1, v)); 767 768 if (v == 0) { /* we were the last */ 769 770 mtx_lock(&ng_nodelist_mtx); 771 node->nd_type->refs--; /* XXX maybe should get types lock? */ 772 LIST_REMOVE(node, nd_nodes); 773 mtx_unlock(&ng_nodelist_mtx); 774 775 mtx_lock(&ng_idhash_mtx); 776 LIST_REMOVE(node, nd_idnodes); 777 mtx_unlock(&ng_idhash_mtx); 778 779 mtx_destroy(&node->nd_input_queue.q_mtx); 780 NG_FREE_NODE(node); 781 } 782 return (v); 783 } 784 785 /************************************************************************ 786 Node ID handling 787 ************************************************************************/ 788 static node_p 789 ng_ID2noderef(ng_ID_t ID) 790 { 791 node_p node; 792 mtx_lock(&ng_idhash_mtx); 793 NG_IDHASH_FIND(ID, node); 794 if(node) 795 NG_NODE_REF(node); 796 mtx_unlock(&ng_idhash_mtx); 797 return(node); 798 } 799 800 ng_ID_t 801 ng_node2ID(node_p node) 802 { 803 return (node ? NG_NODE_ID(node) : 0); 804 } 805 806 /************************************************************************ 807 Node name handling 808 ************************************************************************/ 809 810 /* 811 * Assign a node a name. Once assigned, the name cannot be changed. 812 */ 813 int 814 ng_name_node(node_p node, const char *name) 815 { 816 int i; 817 node_p node2; 818 819 /* Check the name is valid */ 820 for (i = 0; i < NG_NODELEN + 1; i++) { 821 if (name[i] == '\0' || name[i] == '.' || name[i] == ':') 822 break; 823 } 824 if (i == 0 || name[i] != '\0') { 825 TRAP_ERROR(); 826 return (EINVAL); 827 } 828 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */ 829 TRAP_ERROR(); 830 return (EINVAL); 831 } 832 833 /* Check the name isn't already being used */ 834 if ((node2 = ng_name2noderef(node, name)) != NULL) { 835 NG_NODE_UNREF(node2); 836 TRAP_ERROR(); 837 return (EADDRINUSE); 838 } 839 840 /* copy it */ 841 strncpy(NG_NODE_NAME(node), name, NG_NODELEN); 842 843 return (0); 844 } 845 846 /* 847 * Find a node by absolute name. The name should NOT end with ':' 848 * The name "." means "this node" and "[xxx]" means "the node 849 * with ID (ie, at address) xxx". 850 * 851 * Returns the node if found, else NULL. 852 * Eventually should add something faster than a sequential search. 853 * Note it aquires a reference on the node so you can be sure it's still there. 854 */ 855 node_p 856 ng_name2noderef(node_p here, const char *name) 857 { 858 node_p node; 859 ng_ID_t temp; 860 861 /* "." means "this node" */ 862 if (strcmp(name, ".") == 0) { 863 NG_NODE_REF(here); 864 return(here); 865 } 866 867 /* Check for name-by-ID */ 868 if ((temp = ng_decodeidname(name)) != 0) { 869 return (ng_ID2noderef(temp)); 870 } 871 872 /* Find node by name */ 873 mtx_lock(&ng_nodelist_mtx); 874 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 875 if (NG_NODE_IS_VALID(node) 876 && NG_NODE_HAS_NAME(node) 877 && (strcmp(NG_NODE_NAME(node), name) == 0)) { 878 break; 879 } 880 } 881 if (node) 882 NG_NODE_REF(node); 883 mtx_unlock(&ng_nodelist_mtx); 884 return (node); 885 } 886 887 /* 888 * Decode an ID name, eg. "[f03034de]". Returns 0 if the 889 * string is not valid, otherwise returns the value. 890 */ 891 static ng_ID_t 892 ng_decodeidname(const char *name) 893 { 894 const int len = strlen(name); 895 char *eptr; 896 u_long val; 897 898 /* Check for proper length, brackets, no leading junk */ 899 if ((len < 3) 900 || (name[0] != '[') 901 || (name[len - 1] != ']') 902 || (!isxdigit(name[1]))) { 903 return ((ng_ID_t)0); 904 } 905 906 /* Decode number */ 907 val = strtoul(name + 1, &eptr, 16); 908 if ((eptr - name != len - 1) 909 || (val == ULONG_MAX) 910 || (val == 0)) { 911 return ((ng_ID_t)0); 912 } 913 return (ng_ID_t)val; 914 } 915 916 /* 917 * Remove a name from a node. This should only be called 918 * when shutting down and removing the node. 919 * IF we allow name changing this may be more resurected. 920 */ 921 void 922 ng_unname(node_p node) 923 { 924 } 925 926 /************************************************************************ 927 Hook routines 928 Names are not optional. Hooks are always connected, except for a 929 brief moment within these routines. On invalidation or during creation 930 they are connected to the 'dead' hook. 931 ************************************************************************/ 932 933 /* 934 * Remove a hook reference 935 */ 936 void 937 ng_unref_hook(hook_p hook) 938 { 939 int v; 940 941 if (hook == &ng_deadhook) { 942 return; 943 } 944 do { 945 v = hook->hk_refs; 946 } while (! atomic_cmpset_int(&hook->hk_refs, v, v - 1)); 947 948 if (v == 1) { /* we were the last */ 949 if (_NG_HOOK_NODE(hook)) { /* it'll probably be ng_deadnode */ 950 _NG_NODE_UNREF((_NG_HOOK_NODE(hook))); 951 hook->hk_node = NULL; 952 } 953 NG_FREE_HOOK(hook); 954 } 955 } 956 957 /* 958 * Add an unconnected hook to a node. Only used internally. 959 * Assumes node is locked. (XXX not yet true ) 960 */ 961 static int 962 ng_add_hook(node_p node, const char *name, hook_p *hookp) 963 { 964 hook_p hook; 965 int error = 0; 966 967 /* Check that the given name is good */ 968 if (name == NULL) { 969 TRAP_ERROR(); 970 return (EINVAL); 971 } 972 if (ng_findhook(node, name) != NULL) { 973 TRAP_ERROR(); 974 return (EEXIST); 975 } 976 977 /* Allocate the hook and link it up */ 978 NG_ALLOC_HOOK(hook); 979 if (hook == NULL) { 980 TRAP_ERROR(); 981 return (ENOMEM); 982 } 983 hook->hk_refs = 1; /* add a reference for us to return */ 984 hook->hk_flags = HK_INVALID; 985 hook->hk_peer = &ng_deadhook; /* start off this way */ 986 hook->hk_node = node; 987 NG_NODE_REF(node); /* each hook counts as a reference */ 988 989 /* Set hook name */ 990 strncpy(NG_HOOK_NAME(hook), name, NG_HOOKLEN); 991 992 /* 993 * Check if the node type code has something to say about it 994 * If it fails, the unref of the hook will also unref the node. 995 */ 996 if (node->nd_type->newhook != NULL) { 997 if ((error = (*node->nd_type->newhook)(node, hook, name))) { 998 NG_HOOK_UNREF(hook); /* this frees the hook */ 999 return (error); 1000 } 1001 } 1002 /* 1003 * The 'type' agrees so far, so go ahead and link it in. 1004 * We'll ask again later when we actually connect the hooks. 1005 */ 1006 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1007 node->nd_numhooks++; 1008 NG_HOOK_REF(hook); /* one for the node */ 1009 1010 if (hookp) 1011 *hookp = hook; 1012 return (0); 1013 } 1014 1015 /* 1016 * Find a hook 1017 * 1018 * Node types may supply their own optimized routines for finding 1019 * hooks. If none is supplied, we just do a linear search. 1020 * XXX Possibly we should add a reference to the hook? 1021 */ 1022 hook_p 1023 ng_findhook(node_p node, const char *name) 1024 { 1025 hook_p hook; 1026 1027 if (node->nd_type->findhook != NULL) 1028 return (*node->nd_type->findhook)(node, name); 1029 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) { 1030 if (NG_HOOK_IS_VALID(hook) 1031 && (strcmp(NG_HOOK_NAME(hook), name) == 0)) 1032 return (hook); 1033 } 1034 return (NULL); 1035 } 1036 1037 /* 1038 * Destroy a hook 1039 * 1040 * As hooks are always attached, this really destroys two hooks. 1041 * The one given, and the one attached to it. Disconnect the hooks 1042 * from each other first. We reconnect the peer hook to the 'dead' 1043 * hook so that it can still exist after we depart. We then 1044 * send the peer its own destroy message. This ensures that we only 1045 * interact with the peer's structures when it is locked processing that 1046 * message. We hold a reference to the peer hook so we are guaranteed that 1047 * the peer hook and node are still going to exist until 1048 * we are finished there as the hook holds a ref on the node. 1049 * We run this same code again on the peer hook, but that time it is already 1050 * attached to the 'dead' hook. 1051 * 1052 * This routine is called at all stages of hook creation 1053 * on error detection and must be able to handle any such stage. 1054 */ 1055 void 1056 ng_destroy_hook(hook_p hook) 1057 { 1058 hook_p peer = NG_HOOK_PEER(hook); 1059 node_p node = NG_HOOK_NODE(hook); 1060 1061 if (hook == &ng_deadhook) { /* better safe than sorry */ 1062 printf("ng_destroy_hook called on deadhook\n"); 1063 return; 1064 } 1065 hook->hk_flags |= HK_INVALID; /* as soon as possible */ 1066 if (peer && (peer != &ng_deadhook)) { 1067 /* 1068 * Set the peer to point to ng_deadhook 1069 * from this moment on we are effectively independent it. 1070 * send it an rmhook message of it's own. 1071 */ 1072 peer->hk_peer = &ng_deadhook; /* They no longer know us */ 1073 hook->hk_peer = &ng_deadhook; /* Nor us, them */ 1074 if (NG_HOOK_NODE(peer) == &ng_deadnode) { 1075 /* 1076 * If it's already divorced from a node, 1077 * just free it. 1078 */ 1079 /* nothing */ 1080 } else { 1081 ng_rmhook_self(peer); /* Send it a surprise */ 1082 } 1083 NG_HOOK_UNREF(peer); /* account for peer link */ 1084 NG_HOOK_UNREF(hook); /* account for peer link */ 1085 } 1086 1087 /* 1088 * Remove the hook from the node's list to avoid possible recursion 1089 * in case the disconnection results in node shutdown. 1090 */ 1091 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */ 1092 return; 1093 } 1094 LIST_REMOVE(hook, hk_hooks); 1095 node->nd_numhooks--; 1096 if (node->nd_type->disconnect) { 1097 /* 1098 * The type handler may elect to destroy the node so don't 1099 * trust its existance after this point. (except 1100 * that we still hold a reference on it. (which we 1101 * inherrited from the hook we are destroying) 1102 */ 1103 (*node->nd_type->disconnect) (hook); 1104 } 1105 1106 /* 1107 * Note that because we will point to ng_deadnode, the original node 1108 * is not decremented automatically so we do that manually. 1109 */ 1110 _NG_HOOK_NODE(hook) = &ng_deadnode; 1111 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */ 1112 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */ 1113 } 1114 1115 /* 1116 * Take two hooks on a node and merge the connection so that the given node 1117 * is effectively bypassed. 1118 */ 1119 int 1120 ng_bypass(hook_p hook1, hook_p hook2) 1121 { 1122 if (hook1->hk_node != hook2->hk_node) { 1123 TRAP_ERROR(); 1124 return (EINVAL); 1125 } 1126 hook1->hk_peer->hk_peer = hook2->hk_peer; 1127 hook2->hk_peer->hk_peer = hook1->hk_peer; 1128 1129 hook1->hk_peer = &ng_deadhook; 1130 hook2->hk_peer = &ng_deadhook; 1131 1132 /* XXX If we ever cache methods on hooks update them as well */ 1133 ng_destroy_hook(hook1); 1134 ng_destroy_hook(hook2); 1135 return (0); 1136 } 1137 1138 /* 1139 * Install a new netgraph type 1140 */ 1141 int 1142 ng_newtype(struct ng_type *tp) 1143 { 1144 const size_t namelen = strlen(tp->name); 1145 1146 /* Check version and type name fields */ 1147 if ((tp->version != NG_ABI_VERSION) 1148 || (namelen == 0) 1149 || (namelen > NG_TYPELEN)) { 1150 TRAP_ERROR(); 1151 return (EINVAL); 1152 } 1153 1154 /* Check for name collision */ 1155 if (ng_findtype(tp->name) != NULL) { 1156 TRAP_ERROR(); 1157 return (EEXIST); 1158 } 1159 1160 1161 /* Link in new type */ 1162 mtx_lock(&ng_typelist_mtx); 1163 LIST_INSERT_HEAD(&ng_typelist, tp, types); 1164 tp->refs = 1; /* first ref is linked list */ 1165 mtx_unlock(&ng_typelist_mtx); 1166 return (0); 1167 } 1168 1169 /* 1170 * unlink a netgraph type 1171 * If no examples exist 1172 */ 1173 int 1174 ng_rmtype(struct ng_type *tp) 1175 { 1176 /* Check for name collision */ 1177 if (tp->refs != 1) { 1178 TRAP_ERROR(); 1179 return (EBUSY); 1180 } 1181 1182 /* Unlink type */ 1183 mtx_lock(&ng_typelist_mtx); 1184 LIST_REMOVE(tp, types); 1185 mtx_unlock(&ng_typelist_mtx); 1186 return (0); 1187 } 1188 1189 /* 1190 * Look for a type of the name given 1191 */ 1192 struct ng_type * 1193 ng_findtype(const char *typename) 1194 { 1195 struct ng_type *type; 1196 1197 mtx_lock(&ng_typelist_mtx); 1198 LIST_FOREACH(type, &ng_typelist, types) { 1199 if (strcmp(type->name, typename) == 0) 1200 break; 1201 } 1202 mtx_unlock(&ng_typelist_mtx); 1203 return (type); 1204 } 1205 1206 /************************************************************************ 1207 Composite routines 1208 ************************************************************************/ 1209 /* 1210 * Connect two nodes using the specified hooks, using queued functions. 1211 */ 1212 static void 1213 ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2) 1214 { 1215 1216 /* 1217 * When we run, we know that the node 'node' is locked for us. 1218 * Our caller has a reference on the hook. 1219 * Our caller has a reference on the node. 1220 * (In this case our caller is ng_apply_item() ). 1221 * The peer hook has a reference on the hook. 1222 * We are all set up except for the final call to the node, and 1223 * the clearing of the INVALID flag. 1224 */ 1225 if (NG_HOOK_NODE(hook) == &ng_deadnode) { 1226 /* 1227 * The node must have been freed again since we last visited 1228 * here. ng_destry_hook() has this effect but nothing else does. 1229 * We should just release our references and 1230 * free anything we can think of. 1231 * Since we know it's been destroyed, and it's our caller 1232 * that holds the references, just return. 1233 */ 1234 return ; 1235 } 1236 if (hook->hk_node->nd_type->connect) { 1237 if ((*hook->hk_node->nd_type->connect) (hook)) { 1238 ng_destroy_hook(hook); /* also zaps peer */ 1239 printf("failed in ng_con_part3()\n"); 1240 return ; 1241 } 1242 } 1243 /* 1244 * XXX this is wrong for SMP. Possibly we need 1245 * to separate out 'create' and 'invalid' flags. 1246 * should only set flags on hooks we have locked under our node. 1247 */ 1248 hook->hk_flags &= ~HK_INVALID; 1249 return ; 1250 } 1251 1252 static void 1253 ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2) 1254 { 1255 1256 /* 1257 * When we run, we know that the node 'node' is locked for us. 1258 * Our caller has a reference on the hook. 1259 * Our caller has a reference on the node. 1260 * (In this case our caller is ng_apply_item() ). 1261 * The peer hook has a reference on the hook. 1262 * our node pointer points to the 'dead' node. 1263 * First check the hook name is unique. 1264 * Should not happen because we checked before queueing this. 1265 */ 1266 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) { 1267 TRAP_ERROR(); 1268 ng_destroy_hook(hook); /* should destroy peer too */ 1269 printf("failed in ng_con_part2()\n"); 1270 return ; 1271 } 1272 /* 1273 * Check if the node type code has something to say about it 1274 * If it fails, the unref of the hook will also unref the attached node, 1275 * however since that node is 'ng_deadnode' this will do nothing. 1276 * The peer hook will also be destroyed. 1277 */ 1278 if (node->nd_type->newhook != NULL) { 1279 if ((*node->nd_type->newhook)(node, hook, hook->hk_name)) { 1280 ng_destroy_hook(hook); /* should destroy peer too */ 1281 printf("failed in ng_con_part2()\n"); 1282 return ; 1283 } 1284 } 1285 1286 /* 1287 * The 'type' agrees so far, so go ahead and link it in. 1288 * We'll ask again later when we actually connect the hooks. 1289 */ 1290 hook->hk_node = node; /* just overwrite ng_deadnode */ 1291 NG_NODE_REF(node); /* each hook counts as a reference */ 1292 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1293 node->nd_numhooks++; 1294 NG_HOOK_REF(hook); /* one for the node */ 1295 1296 /* 1297 * We now have a symetrical situation, where both hooks have been 1298 * linked to their nodes, the newhook methods have been called 1299 * And the references are all correct. The hooks are still marked 1300 * as invalid, as we have not called the 'connect' methods 1301 * yet. 1302 * We can call the local one immediatly as we have the 1303 * node locked, but we need to queue the remote one. 1304 */ 1305 if (hook->hk_node->nd_type->connect) { 1306 if ((*hook->hk_node->nd_type->connect) (hook)) { 1307 ng_destroy_hook(hook); /* also zaps peer */ 1308 printf("failed in ng_con_part2(A)\n"); 1309 return ; 1310 } 1311 } 1312 if (ng_send_fn(hook->hk_peer->hk_node, hook->hk_peer, 1313 &ng_con_part3, arg1, arg2)) { 1314 printf("failed in ng_con_part2(B)"); 1315 ng_destroy_hook(hook); /* also zaps peer */ 1316 return ; 1317 } 1318 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */ 1319 return ; 1320 } 1321 1322 /* 1323 * Connect this node with another node. We assume that this node is 1324 * currently locked, as we are only called from an NGM_CONNECT message. 1325 */ 1326 static int 1327 ng_con_nodes(node_p node, const char *name, node_p node2, const char *name2) 1328 { 1329 int error; 1330 hook_p hook; 1331 hook_p hook2; 1332 1333 if (ng_findhook(node2, name2) != NULL) { 1334 return(EEXIST); 1335 } 1336 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */ 1337 return (error); 1338 /* Allocate the other hook and link it up */ 1339 NG_ALLOC_HOOK(hook2); 1340 if (hook == NULL) { 1341 TRAP_ERROR(); 1342 ng_destroy_hook(hook); /* XXX check ref counts so far */ 1343 NG_HOOK_UNREF(hook); /* including our ref */ 1344 return (ENOMEM); 1345 } 1346 hook2->hk_refs = 1; /* start with a reference for us. */ 1347 hook2->hk_flags = HK_INVALID; 1348 hook2->hk_peer = hook; /* Link the two together */ 1349 hook->hk_peer = hook2; 1350 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/ 1351 NG_HOOK_REF(hook2); 1352 hook2->hk_node = &ng_deadnode; 1353 strncpy(NG_HOOK_NAME(hook2), name2, NG_HOOKLEN); 1354 1355 /* 1356 * Queue the function above. 1357 * Procesing continues in that function in the lock context of 1358 * the other node. 1359 */ 1360 ng_send_fn(node2, hook2, &ng_con_part2, NULL, 0); 1361 1362 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */ 1363 NG_HOOK_UNREF(hook2); 1364 return (0); 1365 } 1366 1367 /* 1368 * Make a peer and connect. 1369 * We assume that the local node is locked. 1370 * The new node probably doesn't need a lock until 1371 * it has a hook, because it cannot really have any work until then, 1372 * but we should think about it a bit more. 1373 * 1374 * The problem may come if the other node also fires up 1375 * some hardware or a timer or some other source of activation, 1376 * also it may already get a command msg via it's ID. 1377 * 1378 * We could use the same method as ng_con_nodes() but we'd have 1379 * to add ability to remove the node when failing. (Not hard, just 1380 * make arg1 point to the node to remove). 1381 * Unless of course we just ignore failure to connect and leave 1382 * an unconnected node? 1383 */ 1384 static int 1385 ng_mkpeer(node_p node, const char *name, const char *name2, char *type) 1386 { 1387 node_p node2; 1388 hook_p hook1; 1389 hook_p hook2; 1390 int error; 1391 1392 if ((error = ng_make_node(type, &node2))) { 1393 return (error); 1394 } 1395 1396 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */ 1397 ng_rmnode(node2, NULL, NULL, 0); 1398 return (error); 1399 } 1400 1401 if ((error = ng_add_hook(node2, name2, &hook2))) { 1402 ng_rmnode(node2, NULL, NULL, 0); 1403 ng_destroy_hook(hook1); 1404 NG_HOOK_UNREF(hook1); 1405 return (error); 1406 } 1407 1408 /* 1409 * Actually link the two hooks together. 1410 */ 1411 hook1->hk_peer = hook2; 1412 hook2->hk_peer = hook1; 1413 1414 /* Each hook is referenced by the other */ 1415 NG_HOOK_REF(hook1); 1416 NG_HOOK_REF(hook2); 1417 1418 /* Give each node the opportunity to veto the pending connection */ 1419 if (hook1->hk_node->nd_type->connect) { 1420 error = (*hook1->hk_node->nd_type->connect) (hook1); 1421 } 1422 1423 if ((error == 0) && hook2->hk_node->nd_type->connect) { 1424 error = (*hook2->hk_node->nd_type->connect) (hook2); 1425 1426 } 1427 1428 /* 1429 * drop the references we were holding on the two hooks. 1430 */ 1431 if (error) { 1432 ng_destroy_hook(hook2); /* also zaps hook1 */ 1433 ng_rmnode(node2, NULL, NULL, 0); 1434 } else { 1435 /* As a last act, allow the hooks to be used */ 1436 hook1->hk_flags &= ~HK_INVALID; 1437 hook2->hk_flags &= ~HK_INVALID; 1438 } 1439 NG_HOOK_UNREF(hook1); 1440 NG_HOOK_UNREF(hook2); 1441 return (error); 1442 } 1443 1444 /************************************************************************ 1445 Utility routines to send self messages 1446 ************************************************************************/ 1447 1448 /* Shut this node down as soon as everyone is clear of it */ 1449 /* Should add arg "immediatly" to jump the queue */ 1450 int 1451 ng_rmnode_self(node_p node) 1452 { 1453 int error; 1454 1455 if (node == &ng_deadnode) 1456 return (0); 1457 node->nd_flags |= NG_INVALID; 1458 if (node->nd_flags & NG_CLOSING) 1459 return (0); 1460 1461 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0); 1462 return (error); 1463 } 1464 1465 static void 1466 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2) 1467 { 1468 ng_destroy_hook(hook); 1469 return ; 1470 } 1471 1472 int 1473 ng_rmhook_self(hook_p hook) 1474 { 1475 int error; 1476 node_p node = NG_HOOK_NODE(hook); 1477 1478 if (node == &ng_deadnode) 1479 return (0); 1480 1481 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0); 1482 return (error); 1483 } 1484 1485 /*********************************************************************** 1486 * Parse and verify a string of the form: <NODE:><PATH> 1487 * 1488 * Such a string can refer to a specific node or a specific hook 1489 * on a specific node, depending on how you look at it. In the 1490 * latter case, the PATH component must not end in a dot. 1491 * 1492 * Both <NODE:> and <PATH> are optional. The <PATH> is a string 1493 * of hook names separated by dots. This breaks out the original 1494 * string, setting *nodep to "NODE" (or NULL if none) and *pathp 1495 * to "PATH" (or NULL if degenerate). Also, *hookp will point to 1496 * the final hook component of <PATH>, if any, otherwise NULL. 1497 * 1498 * This returns -1 if the path is malformed. The char ** are optional. 1499 ***********************************************************************/ 1500 int 1501 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp) 1502 { 1503 char *node, *path, *hook; 1504 int k; 1505 1506 /* 1507 * Extract absolute NODE, if any 1508 */ 1509 for (path = addr; *path && *path != ':'; path++); 1510 if (*path) { 1511 node = addr; /* Here's the NODE */ 1512 *path++ = '\0'; /* Here's the PATH */ 1513 1514 /* Node name must not be empty */ 1515 if (!*node) 1516 return -1; 1517 1518 /* A name of "." is OK; otherwise '.' not allowed */ 1519 if (strcmp(node, ".") != 0) { 1520 for (k = 0; node[k]; k++) 1521 if (node[k] == '.') 1522 return -1; 1523 } 1524 } else { 1525 node = NULL; /* No absolute NODE */ 1526 path = addr; /* Here's the PATH */ 1527 } 1528 1529 /* Snoop for illegal characters in PATH */ 1530 for (k = 0; path[k]; k++) 1531 if (path[k] == ':') 1532 return -1; 1533 1534 /* Check for no repeated dots in PATH */ 1535 for (k = 0; path[k]; k++) 1536 if (path[k] == '.' && path[k + 1] == '.') 1537 return -1; 1538 1539 /* Remove extra (degenerate) dots from beginning or end of PATH */ 1540 if (path[0] == '.') 1541 path++; 1542 if (*path && path[strlen(path) - 1] == '.') 1543 path[strlen(path) - 1] = 0; 1544 1545 /* If PATH has a dot, then we're not talking about a hook */ 1546 if (*path) { 1547 for (hook = path, k = 0; path[k]; k++) 1548 if (path[k] == '.') { 1549 hook = NULL; 1550 break; 1551 } 1552 } else 1553 path = hook = NULL; 1554 1555 /* Done */ 1556 if (nodep) 1557 *nodep = node; 1558 if (pathp) 1559 *pathp = path; 1560 if (hookp) 1561 *hookp = hook; 1562 return (0); 1563 } 1564 1565 /* 1566 * Given a path, which may be absolute or relative, and a starting node, 1567 * return the destination node. 1568 */ 1569 int 1570 ng_path2noderef(node_p here, const char *address, 1571 node_p *destp, hook_p *lasthook) 1572 { 1573 char fullpath[NG_PATHLEN + 1]; 1574 char *nodename, *path, pbuf[2]; 1575 node_p node, oldnode; 1576 char *cp; 1577 hook_p hook = NULL; 1578 1579 /* Initialize */ 1580 if (destp == NULL) { 1581 TRAP_ERROR(); 1582 return EINVAL; 1583 } 1584 *destp = NULL; 1585 1586 /* Make a writable copy of address for ng_path_parse() */ 1587 strncpy(fullpath, address, sizeof(fullpath) - 1); 1588 fullpath[sizeof(fullpath) - 1] = '\0'; 1589 1590 /* Parse out node and sequence of hooks */ 1591 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) { 1592 TRAP_ERROR(); 1593 return EINVAL; 1594 } 1595 if (path == NULL) { 1596 pbuf[0] = '.'; /* Needs to be writable */ 1597 pbuf[1] = '\0'; 1598 path = pbuf; 1599 } 1600 1601 /* 1602 * For an absolute address, jump to the starting node. 1603 * Note that this holds a reference on the node for us. 1604 * Don't forget to drop the reference if we don't need it. 1605 */ 1606 if (nodename) { 1607 node = ng_name2noderef(here, nodename); 1608 if (node == NULL) { 1609 TRAP_ERROR(); 1610 return (ENOENT); 1611 } 1612 } else { 1613 if (here == NULL) { 1614 TRAP_ERROR(); 1615 return (EINVAL); 1616 } 1617 node = here; 1618 NG_NODE_REF(node); 1619 } 1620 1621 /* 1622 * Now follow the sequence of hooks 1623 * XXX 1624 * We actually cannot guarantee that the sequence 1625 * is not being demolished as we crawl along it 1626 * without extra-ordinary locking etc. 1627 * So this is a bit dodgy to say the least. 1628 * We can probably hold up some things by holding 1629 * the nodelist mutex for the time of this 1630 * crawl if we wanted.. At least that way we wouldn't have to 1631 * worry about the nodes dissappearing, but the hooks would still 1632 * be a problem. 1633 */ 1634 for (cp = path; node != NULL && *cp != '\0'; ) { 1635 char *segment; 1636 1637 /* 1638 * Break out the next path segment. Replace the dot we just 1639 * found with a NUL; "cp" points to the next segment (or the 1640 * NUL at the end). 1641 */ 1642 for (segment = cp; *cp != '\0'; cp++) { 1643 if (*cp == '.') { 1644 *cp++ = '\0'; 1645 break; 1646 } 1647 } 1648 1649 /* Empty segment */ 1650 if (*segment == '\0') 1651 continue; 1652 1653 /* We have a segment, so look for a hook by that name */ 1654 hook = ng_findhook(node, segment); 1655 1656 /* Can't get there from here... */ 1657 if (hook == NULL 1658 || NG_HOOK_PEER(hook) == NULL 1659 || NG_HOOK_NOT_VALID(hook) 1660 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) { 1661 TRAP_ERROR(); 1662 NG_NODE_UNREF(node); 1663 #if 0 1664 printf("hooknotvalid %s %s %d %d %d %d ", 1665 path, 1666 segment, 1667 hook == NULL, 1668 NG_HOOK_PEER(hook) == NULL, 1669 NG_HOOK_NOT_VALID(hook), 1670 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))); 1671 #endif 1672 return (ENOENT); 1673 } 1674 1675 /* 1676 * Hop on over to the next node 1677 * XXX 1678 * Big race conditions here as hooks and nodes go away 1679 * *** Idea.. store an ng_ID_t in each hook and use that 1680 * instead of the direct hook in this crawl? 1681 */ 1682 oldnode = node; 1683 if ((node = NG_PEER_NODE(hook))) 1684 NG_NODE_REF(node); /* XXX RACE */ 1685 NG_NODE_UNREF(oldnode); /* XXX another race */ 1686 if (NG_NODE_NOT_VALID(node)) { 1687 NG_NODE_UNREF(node); /* XXX more races */ 1688 node = NULL; 1689 } 1690 } 1691 1692 /* If node somehow missing, fail here (probably this is not needed) */ 1693 if (node == NULL) { 1694 TRAP_ERROR(); 1695 return (ENXIO); 1696 } 1697 1698 /* Done */ 1699 *destp = node; 1700 if (lasthook != NULL) 1701 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL); 1702 return (0); 1703 } 1704 1705 /***************************************************************\ 1706 * Input queue handling. 1707 * All activities are submitted to the node via the input queue 1708 * which implements a multiple-reader/single-writer gate. 1709 * Items which cannot be handled immeditly are queued. 1710 * 1711 * read-write queue locking inline functions * 1712 \***************************************************************/ 1713 1714 static __inline item_p ng_dequeue(struct ng_queue * ngq); 1715 static __inline item_p ng_acquire_read(struct ng_queue * ngq, 1716 item_p item); 1717 static __inline item_p ng_acquire_write(struct ng_queue * ngq, 1718 item_p item); 1719 static __inline void ng_leave_read(struct ng_queue * ngq); 1720 static __inline void ng_leave_write(struct ng_queue * ngq); 1721 static __inline void ng_queue_rw(struct ng_queue * ngq, 1722 item_p item, int rw); 1723 1724 /* 1725 * Definition of the bits fields in the ng_queue flag word. 1726 * Defined here rather than in netgraph.h because no-one should fiddle 1727 * with them. 1728 * 1729 * The ordering here may be important! don't shuffle these. 1730 */ 1731 /*- 1732 Safety Barrier--------+ (adjustable to suit taste) (not used yet) 1733 | 1734 V 1735 +-------+-------+-------+-------+-------+-------+-------+-------+ 1736 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1737 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |R|A|W| 1738 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |P|W|P| 1739 +-------+-------+-------+-------+-------+-------+-------+-------+ 1740 \___________________________ ____________________________/ | | | 1741 V | | | 1742 [active reader count] | | | 1743 | | | 1744 Read Pending ------------------------------------+ | | 1745 | | 1746 Active Writer -------------------------------------+ | 1747 | 1748 Write Pending ---------------------------------------+ 1749 1750 1751 */ 1752 #define WRITE_PENDING 0x00000001 1753 #define WRITER_ACTIVE 0x00000002 1754 #define READ_PENDING 0x00000004 1755 #define READER_INCREMENT 0x00000008 1756 #define READER_MASK 0xfffffff0 /* Not valid if WRITER_ACTIVE is set */ 1757 #define SAFETY_BARRIER 0x00100000 /* 64K items queued should be enough */ 1758 1759 /* Defines of more elaborate states on the queue */ 1760 /* Mask of bits a read cares about */ 1761 #define NGQ_RMASK (WRITE_PENDING|WRITER_ACTIVE|READ_PENDING) 1762 1763 /* Mask of bits a write cares about */ 1764 #define NGQ_WMASK (NGQ_RMASK|READER_MASK) 1765 1766 /* tests to decide if we could get a read or write off the queue */ 1767 #define CAN_GET_READ(flag) ((flag & NGQ_RMASK) == READ_PENDING) 1768 #define CAN_GET_WRITE(flag) ((flag & NGQ_WMASK) == WRITE_PENDING) 1769 1770 /* Is there a chance of getting ANY work off the queue? */ 1771 #define CAN_GET_WORK(flag) (CAN_GET_READ(flag) || CAN_GET_WRITE(flag)) 1772 1773 /* 1774 * Taking into account the current state of the queue and node, possibly take 1775 * the next entry off the queue and return it. Return NULL if there was 1776 * nothing we could return, either because there really was nothing there, or 1777 * because the node was in a state where it cannot yet process the next item 1778 * on the queue. 1779 * 1780 * This MUST MUST MUST be called with the mutex held. 1781 */ 1782 static __inline item_p 1783 ng_dequeue(struct ng_queue *ngq) 1784 { 1785 item_p item; 1786 u_int add_arg; 1787 1788 if (CAN_GET_READ(ngq->q_flags)) { 1789 /* 1790 * Head of queue is a reader and we have no write active. 1791 * We don't care how many readers are already active. 1792 * Adjust the flags for the item we are about to dequeue. 1793 * Add the correct increment for the reader count as well. 1794 */ 1795 add_arg = (READER_INCREMENT - READ_PENDING); 1796 } else if (CAN_GET_WRITE(ngq->q_flags)) { 1797 /* 1798 * There is a pending write, no readers and no active writer. 1799 * This means we can go ahead with the pending writer. Note 1800 * the fact that we now have a writer, ready for when we take 1801 * it off the queue. 1802 * 1803 * We don't need to worry about a possible collision with the 1804 * fasttrack reader. 1805 * 1806 * The fasttrack thread may take a long time to discover that we 1807 * are running so we would have an inconsistent state in the 1808 * flags for a while. Since we ignore the reader count 1809 * entirely when the WRITER_ACTIVE flag is set, this should 1810 * not matter (in fact it is defined that way). If it tests 1811 * the flag before this operation, the WRITE_PENDING flag 1812 * will make it fail, and if it tests it later, the 1813 * WRITER_ACTIVE flag will do the same. If it is SO slow that 1814 * we have actually completed the operation, and neither flag 1815 * is set (nor the READ_PENDING) by the time that it tests 1816 * the flags, then it is actually ok for it to continue. If 1817 * it completes and we've finished and the read pending is 1818 * set it still fails. 1819 * 1820 * So we can just ignore it, as long as we can ensure that the 1821 * transition from WRITE_PENDING state to the WRITER_ACTIVE 1822 * state is atomic. 1823 * 1824 * After failing, first it will be held back by the mutex, then 1825 * when it can proceed, it will queue its request, then it 1826 * would arrive at this function. Usually it will have to 1827 * leave empty handed because the ACTIVE WRITER bit will be 1828 * set. 1829 * 1830 * Adjust the flags for the item we are about to dequeue 1831 * and for the new active writer. 1832 */ 1833 add_arg = (WRITER_ACTIVE - WRITE_PENDING); 1834 /* 1835 * We want to write "active writer, no readers " Now go make 1836 * it true. In fact there may be a number in the readers 1837 * count but we know it is not true and will be fixed soon. 1838 * We will fix the flags for the next pending entry in a 1839 * moment. 1840 */ 1841 } else { 1842 /* 1843 * We can't dequeue anything.. return and say so. Probably we 1844 * have a write pending and the readers count is non zero. If 1845 * we got here because a reader hit us just at the wrong 1846 * moment with the fasttrack code, and put us in a strange 1847 * state, then it will be through in just a moment, (as soon 1848 * as we release the mutex) and keep things moving. 1849 * Make sure we remove ourselves from the work queue. 1850 */ 1851 ng_worklist_remove(ngq->q_node); 1852 return (0); 1853 } 1854 1855 /* 1856 * Now we dequeue the request (whatever it may be) and correct the 1857 * pending flags and the next and last pointers. 1858 */ 1859 item = ngq->queue; 1860 ngq->queue = item->el_next; 1861 if (ngq->last == &(item->el_next)) { 1862 /* 1863 * that was the last entry in the queue so set the 'last 1864 * pointer up correctly and make sure the pending flags are 1865 * clear. 1866 */ 1867 ngq->last = &(ngq->queue); 1868 /* 1869 * Whatever flag was set will be cleared and 1870 * the new acive field will be set by the add as well, 1871 * so we don't need to change add_arg. 1872 * But we know we don't need to be on the work list. 1873 */ 1874 atomic_add_long(&ngq->q_flags, add_arg); 1875 ng_worklist_remove(ngq->q_node); 1876 } else { 1877 /* 1878 * Since there is something on the queue, note what it is 1879 * in the flags word. 1880 */ 1881 if ((ngq->queue->el_flags & NGQF_RW) == NGQF_READER) { 1882 add_arg += READ_PENDING; 1883 } else { 1884 add_arg += WRITE_PENDING; 1885 } 1886 atomic_add_long(&ngq->q_flags, add_arg); 1887 /* 1888 * If we see more doable work, make sure we are 1889 * on the work queue. 1890 */ 1891 if (CAN_GET_WORK(ngq->q_flags)) { 1892 ng_setisr(ngq->q_node); 1893 } 1894 } 1895 /* 1896 * We have successfully cleared the old pending flag, set the new one 1897 * if it is needed, and incremented the appropriate active field. 1898 * (all in one atomic addition.. ) 1899 */ 1900 return (item); 1901 } 1902 1903 /* 1904 * Queue a packet to be picked up by someone else. 1905 * We really don't care who, but we can't or don't want to hang around 1906 * to process it ourselves. We are probably an interrupt routine.. 1907 * 1 = writer, 0 = reader 1908 */ 1909 #define NGQRW_R 0 1910 #define NGQRW_W 1 1911 static __inline void 1912 ng_queue_rw(struct ng_queue * ngq, item_p item, int rw) 1913 { 1914 item->el_next = NULL; /* maybe not needed */ 1915 *ngq->last = item; 1916 /* 1917 * If it was the first item in the queue then we need to 1918 * set the last pointer and the type flags. 1919 */ 1920 if (ngq->last == &(ngq->queue)) { 1921 /* 1922 * When called with constants for rw, the optimiser will 1923 * remove the unneeded branch below. 1924 */ 1925 if (rw == NGQRW_W) { 1926 atomic_add_long(&ngq->q_flags, WRITE_PENDING); 1927 } else { 1928 atomic_add_long(&ngq->q_flags, READ_PENDING); 1929 } 1930 } 1931 ngq->last = &(item->el_next); 1932 } 1933 1934 1935 /* 1936 * This function 'cheats' in that it first tries to 'grab' the use of the 1937 * node, without going through the mutex. We can do this becasue of the 1938 * semantics of the lock. The semantics include a clause that says that the 1939 * value of the readers count is invalid if the WRITER_ACTIVE flag is set. It 1940 * also says that the WRITER_ACTIVE flag cannot be set if the readers count 1941 * is not zero. Note that this talks about what is valid to SET the 1942 * WRITER_ACTIVE flag, because from the moment it is set, the value if the 1943 * reader count is immaterial, and not valid. The two 'pending' flags have a 1944 * similar effect, in that If they are orthogonal to the two active fields in 1945 * how they are set, but if either is set, the attempted 'grab' need to be 1946 * backed out because there is earlier work, and we maintain ordering in the 1947 * queue. The result of this is that the reader request can try obtain use of 1948 * the node with only a single atomic addition, and without any of the mutex 1949 * overhead. If this fails the operation degenerates to the same as for other 1950 * cases. 1951 * 1952 */ 1953 static __inline item_p 1954 ng_acquire_read(struct ng_queue *ngq, item_p item) 1955 { 1956 1957 /* ######### Hack alert ######### */ 1958 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 1959 if ((ngq->q_flags & NGQ_RMASK) == 0) { 1960 /* Successfully grabbed node */ 1961 return (item); 1962 } 1963 /* undo the damage if we didn't succeed */ 1964 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 1965 1966 /* ######### End Hack alert ######### */ 1967 mtx_lock_spin((&ngq->q_mtx)); 1968 /* 1969 * Try again. Another processor (or interrupt for that matter) may 1970 * have removed the last queued item that was stopping us from 1971 * running, between the previous test, and the moment that we took 1972 * the mutex. (Or maybe a writer completed.) 1973 */ 1974 if ((ngq->q_flags & NGQ_RMASK) == 0) { 1975 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 1976 mtx_unlock_spin((&ngq->q_mtx)); 1977 return (item); 1978 } 1979 1980 /* 1981 * and queue the request for later. 1982 */ 1983 item->el_flags |= NGQF_READER; 1984 ng_queue_rw(ngq, item, NGQRW_R); 1985 1986 /* 1987 * Ok, so that's the item successfully queued for later. So now we 1988 * see if we can dequeue something to run instead. 1989 */ 1990 item = ng_dequeue(ngq); 1991 mtx_unlock_spin(&(ngq->q_mtx)); 1992 return (item); 1993 } 1994 1995 static __inline item_p 1996 ng_acquire_write(struct ng_queue *ngq, item_p item) 1997 { 1998 restart: 1999 mtx_lock_spin(&(ngq->q_mtx)); 2000 /* 2001 * If there are no readers, no writer, and no pending packets, then 2002 * we can just go ahead. In all other situations we need to queue the 2003 * request 2004 */ 2005 if ((ngq->q_flags & NGQ_WMASK) == 0) { 2006 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE); 2007 mtx_unlock_spin((&ngq->q_mtx)); 2008 if (ngq->q_flags & READER_MASK) { 2009 /* Collision with fast-track reader */ 2010 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2011 goto restart; 2012 } 2013 return (item); 2014 } 2015 2016 /* 2017 * and queue the request for later. 2018 */ 2019 item->el_flags &= ~NGQF_RW; 2020 ng_queue_rw(ngq, item, NGQRW_W); 2021 2022 /* 2023 * Ok, so that's the item successfully queued for later. So now we 2024 * see if we can dequeue something to run instead. 2025 */ 2026 item = ng_dequeue(ngq); 2027 mtx_unlock_spin(&(ngq->q_mtx)); 2028 return (item); 2029 } 2030 2031 static __inline void 2032 ng_leave_read(struct ng_queue *ngq) 2033 { 2034 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 2035 } 2036 2037 static __inline void 2038 ng_leave_write(struct ng_queue *ngq) 2039 { 2040 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2041 } 2042 2043 static void 2044 ng_flush_input_queue(struct ng_queue * ngq) 2045 { 2046 item_p item; 2047 u_int add_arg; 2048 mtx_lock_spin(&ngq->q_mtx); 2049 for (;;) { 2050 /* Now take a look at what's on the queue */ 2051 if (ngq->q_flags & READ_PENDING) { 2052 add_arg = -READ_PENDING; 2053 } else if (ngq->q_flags & WRITE_PENDING) { 2054 add_arg = -WRITE_PENDING; 2055 } else { 2056 break; 2057 } 2058 2059 item = ngq->queue; 2060 ngq->queue = item->el_next; 2061 if (ngq->last == &(item->el_next)) { 2062 ngq->last = &(ngq->queue); 2063 } else { 2064 if ((ngq->queue->el_flags & NGQF_RW) == NGQF_READER) { 2065 add_arg += READ_PENDING; 2066 } else { 2067 add_arg += WRITE_PENDING; 2068 } 2069 } 2070 atomic_add_long(&ngq->q_flags, add_arg); 2071 2072 mtx_lock_spin(&ngq->q_mtx); 2073 NG_FREE_ITEM(item); 2074 mtx_unlock_spin(&ngq->q_mtx); 2075 } 2076 /* 2077 * Take us off the work queue if we are there. 2078 * We definatly have no work to be done. 2079 */ 2080 ng_worklist_remove(ngq->q_node); 2081 mtx_unlock_spin(&ngq->q_mtx); 2082 } 2083 2084 /*********************************************************************** 2085 * Externally visible method for sending or queueing messages or data. 2086 ***********************************************************************/ 2087 2088 /* 2089 * The module code should have filled out the item correctly by this stage: 2090 * Common: 2091 * reference to destination node. 2092 * Reference to destination rcv hook if relevant. 2093 * Data: 2094 * pointer to mbuf 2095 * pointer to metadata 2096 * Control_Message: 2097 * pointer to msg. 2098 * ID of original sender node. (return address) 2099 * Function: 2100 * Function pointer 2101 * void * argument 2102 * integer argument 2103 * 2104 * The nodes have several routines and macros to help with this task: 2105 */ 2106 2107 int 2108 ng_snd_item(item_p item, int queue) 2109 { 2110 hook_p hook = NGI_HOOK(item); 2111 node_p node = NGI_NODE(item); 2112 int rw; 2113 int error = 0, ierror; 2114 item_p oitem; 2115 struct ng_queue * ngq = &node->nd_input_queue; 2116 2117 #ifdef NETGRAPH_DEBUG 2118 _ngi_check(item, __FILE__, __LINE__); 2119 #endif 2120 2121 if (item == NULL) { 2122 TRAP_ERROR(); 2123 return (EINVAL); /* failed to get queue element */ 2124 } 2125 if (node == NULL) { 2126 NG_FREE_ITEM(item); 2127 TRAP_ERROR(); 2128 return (EINVAL); /* No address */ 2129 } 2130 switch(item->el_flags & NGQF_TYPE) { 2131 case NGQF_DATA: 2132 /* 2133 * DATA MESSAGE 2134 * Delivered to a node via a non-optional hook. 2135 * Both should be present in the item even though 2136 * the node is derivable from the hook. 2137 * References are held on both by the item. 2138 */ 2139 CHECK_DATA_MBUF(NGI_M(item)); 2140 if (hook == NULL) { 2141 NG_FREE_ITEM(item); 2142 TRAP_ERROR(); 2143 return(EINVAL); 2144 } 2145 if ((NG_HOOK_NOT_VALID(hook)) 2146 || (NG_NODE_NOT_VALID(NG_HOOK_NODE(hook)))) { 2147 NG_FREE_ITEM(item); 2148 return (ENOTCONN); 2149 } 2150 if ((hook->hk_flags & HK_QUEUE)) { 2151 queue = 1; 2152 } 2153 /* By default data is a reader in the locking scheme */ 2154 item->el_flags |= NGQF_READER; 2155 rw = NGQRW_R; 2156 break; 2157 case NGQF_MESG: 2158 /* 2159 * CONTROL MESSAGE 2160 * Delivered to a node. 2161 * Hook is optional. 2162 * References are held by the item on the node and 2163 * the hook if it is present. 2164 */ 2165 if (hook && (hook->hk_flags & HK_QUEUE)) { 2166 queue = 1; 2167 } 2168 /* Data messages count as writers unles explicitly exempted */ 2169 if (NGI_MSG(item)->header.cmd & NGM_READONLY) { 2170 item->el_flags |= NGQF_READER; 2171 rw = NGQRW_R; 2172 } else { 2173 item->el_flags &= ~NGQF_RW; 2174 rw = NGQRW_W; 2175 } 2176 break; 2177 case NGQF_FN: 2178 item->el_flags &= ~NGQF_RW; 2179 rw = NGQRW_W; 2180 break; 2181 default: 2182 NG_FREE_ITEM(item); 2183 TRAP_ERROR(); 2184 return (EINVAL); 2185 } 2186 /* 2187 * If the node specifies single threading, force writer semantics 2188 * Similarly the node may say one hook always produces writers. 2189 * These are over-rides. 2190 */ 2191 if ((node->nd_flags & NG_FORCE_WRITER) 2192 || (hook && (hook->hk_flags & HK_FORCE_WRITER))) { 2193 rw = NGQRW_W; 2194 item->el_flags &= ~NGQF_READER; 2195 } 2196 if (queue) { 2197 /* Put it on the queue for that node*/ 2198 #ifdef NETGRAPH_DEBUG 2199 _ngi_check(item, __FILE__, __LINE__); 2200 #endif 2201 mtx_lock_spin(&(ngq->q_mtx)); 2202 ng_queue_rw(ngq, item, rw); 2203 /* 2204 * If there are active elements then we can rely on 2205 * them. if not we should not rely on another packet 2206 * coming here by another path, 2207 * so it is best to put us in the netisr list. 2208 * We can take the worklist lock with the node locked 2209 * BUT NOT THE REVERSE! 2210 */ 2211 if (CAN_GET_WORK(ngq->q_flags)) { 2212 ng_setisr(node); 2213 } 2214 mtx_unlock_spin(&(ngq->q_mtx)); 2215 return (0); 2216 } 2217 /* 2218 * Take a queue item and a node and see if we can apply the item to 2219 * the node. We may end up getting a different item to apply instead. 2220 * Will allow for a piggyback reply only in the case where 2221 * there is no queueing. 2222 */ 2223 2224 oitem = item; 2225 /* 2226 * We already decided how we will be queueud or treated. 2227 * Try get the appropriate operating permission. 2228 */ 2229 if (rw == NGQRW_R) { 2230 item = ng_acquire_read(ngq, item); 2231 } else { 2232 item = ng_acquire_write(ngq, item); 2233 } 2234 2235 /* 2236 * May have come back with a different item. 2237 * or maybe none at all. The one we started with will 2238 * have been queued in thises cases. 2239 */ 2240 if (item == NULL) { 2241 return (0); 2242 } 2243 2244 #ifdef NETGRAPH_DEBUG 2245 _ngi_check(item, __FILE__, __LINE__); 2246 #endif 2247 /* 2248 * Take over the reference frm the item. 2249 * Hold it until the called function returns. 2250 */ 2251 NGI_GET_NODE(item, node); /* zaps stored node */ 2252 2253 ierror = ng_apply_item(node, item); /* drops r/w lock when done */ 2254 2255 /* only return an error if it was our initial item.. (compat hack) */ 2256 if (oitem == item) { 2257 error = ierror; 2258 } 2259 2260 /* 2261 * If the node goes away when we remove the reference, 2262 * whatever we just did caused it.. whatever we do, DO NOT 2263 * access the node again! 2264 */ 2265 if (NG_NODE_UNREF(node) == 0) { 2266 return (error); 2267 } 2268 2269 /* 2270 * Now we've handled the packet we brought, (or a friend of it) let's 2271 * look for any other packets that may have been queued up. We hold 2272 * no locks, so if someone puts something in the queue after 2273 * we check that it is empty, it is their problem 2274 * to ensure it is processed. If we have the netisr thread cme in here 2275 * while we still say we have stuff to do, we may get a boost 2276 * in SMP systems. :-) 2277 */ 2278 for (;;) { 2279 /* 2280 * dequeue acquires and adjusts the input_queue as it dequeues 2281 * packets. It acquires the rw lock as needed. 2282 */ 2283 mtx_lock_spin(&ngq->q_mtx); 2284 item = ng_dequeue(ngq); /* fixes worklist too*/ 2285 if (!item) { 2286 mtx_unlock_spin(&ngq->q_mtx); 2287 return (error); 2288 } 2289 mtx_unlock_spin(&ngq->q_mtx); 2290 2291 /* 2292 * Take over the reference frm the item. 2293 * Hold it until the called function returns. 2294 */ 2295 2296 NGI_GET_NODE(item, node); /* zaps stored node */ 2297 2298 /* 2299 * We have the appropriate lock, so run the item. 2300 * When finished it will drop the lock accordingly 2301 */ 2302 ierror = ng_apply_item(node, item); 2303 2304 /* 2305 * only return an error if it was our initial 2306 * item.. (compat hack) 2307 */ 2308 if (oitem == item) { 2309 error = ierror; 2310 } 2311 2312 /* 2313 * If the node goes away when we remove the reference, 2314 * whatever we just did caused it.. whatever we do, DO NOT 2315 * access the node again! 2316 */ 2317 if (NG_NODE_UNREF(node) == 0) { 2318 break; 2319 } 2320 } 2321 return (error); 2322 } 2323 2324 /* 2325 * We have an item that was possibly queued somewhere. 2326 * It should contain all the information needed 2327 * to run it on the appropriate node/hook. 2328 */ 2329 static int 2330 ng_apply_item(node_p node, item_p item) 2331 { 2332 hook_p hook; 2333 int was_reader = ((item->el_flags & NGQF_RW)); 2334 int error = 0; 2335 ng_rcvdata_t *rcvdata; 2336 ng_rcvmsg_t *rcvmsg; 2337 2338 NGI_GET_HOOK(item, hook); /* clears stored hook */ 2339 #ifdef NETGRAPH_DEBUG 2340 _ngi_check(item, __FILE__, __LINE__); 2341 #endif 2342 switch (item->el_flags & NGQF_TYPE) { 2343 case NGQF_DATA: 2344 /* 2345 * Check things are still ok as when we were queued. 2346 */ 2347 if ((hook == NULL) 2348 || NG_HOOK_NOT_VALID(hook) 2349 || NG_NODE_NOT_VALID(node) ) { 2350 error = EIO; 2351 NG_FREE_ITEM(item); 2352 break; 2353 } 2354 /* 2355 * If no receive method, just silently drop it. 2356 * Give preference to the hook over-ride method 2357 */ 2358 if ((!(rcvdata = hook->hk_rcvdata)) 2359 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) { 2360 error = 0; 2361 NG_FREE_ITEM(item); 2362 break; 2363 } 2364 error = (*rcvdata)(hook, item); 2365 break; 2366 case NGQF_MESG: 2367 if (hook) { 2368 if (NG_HOOK_NOT_VALID(hook)) { 2369 /* 2370 * The hook has been zapped then we can't 2371 * use it. Immediatly drop its reference. 2372 * The message may not need it. 2373 */ 2374 NG_HOOK_UNREF(hook); 2375 hook = NULL; 2376 } 2377 } 2378 /* 2379 * Similarly, if the node is a zombie there is 2380 * nothing we can do with it, drop everything. 2381 */ 2382 if (NG_NODE_NOT_VALID(node)) { 2383 TRAP_ERROR(); 2384 error = EINVAL; 2385 NG_FREE_ITEM(item); 2386 } else { 2387 /* 2388 * Call the appropriate message handler for the object. 2389 * It is up to the message handler to free the message. 2390 * If it's a generic message, handle it generically, 2391 * otherwise call the type's message handler 2392 * (if it exists) 2393 * XXX (race). Remember that a queued message may 2394 * reference a node or hook that has just been 2395 * invalidated. It will exist as the queue code 2396 * is holding a reference, but.. 2397 */ 2398 2399 struct ng_mesg *msg = NGI_MSG(item); 2400 2401 /* 2402 * check if the generic handler owns it. 2403 */ 2404 if ((msg->header.typecookie == NGM_GENERIC_COOKIE) 2405 && ((msg->header.flags & NGF_RESP) == 0)) { 2406 error = ng_generic_msg(node, item, hook); 2407 break; 2408 } 2409 /* 2410 * Now see if there is a handler (hook or node specific) 2411 * in the target node. If none, silently discard. 2412 */ 2413 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) 2414 && (!(rcvmsg = node->nd_type->rcvmsg))) { 2415 TRAP_ERROR(); 2416 error = 0; 2417 NG_FREE_ITEM(item); 2418 break; 2419 } 2420 error = (*rcvmsg)(node, item, hook); 2421 } 2422 break; 2423 case NGQF_FN: 2424 /* 2425 * We have to implicitly trust the hook, 2426 * as some of these are used for system purposes 2427 * where the hook is invalid. In the case of 2428 * the shutdown message we allow it to hit 2429 * even if the node is invalid. 2430 */ 2431 if ((NG_NODE_NOT_VALID(node)) 2432 && (NGI_FN(item) != &ng_rmnode)) { 2433 TRAP_ERROR(); 2434 error = EINVAL; 2435 break; 2436 } 2437 (*NGI_FN(item))(node, hook, NGI_ARG1(item), NGI_ARG2(item)); 2438 NG_FREE_ITEM(item); 2439 break; 2440 2441 } 2442 /* 2443 * We held references on some of the resources 2444 * that we took from the item. Now that we have 2445 * finished doing everything, drop those references. 2446 */ 2447 if (hook) { 2448 NG_HOOK_UNREF(hook); 2449 } 2450 2451 if (was_reader) { 2452 ng_leave_read(&node->nd_input_queue); 2453 } else { 2454 ng_leave_write(&node->nd_input_queue); 2455 } 2456 return (error); 2457 } 2458 2459 /*********************************************************************** 2460 * Implement the 'generic' control messages 2461 ***********************************************************************/ 2462 static int 2463 ng_generic_msg(node_p here, item_p item, hook_p lasthook) 2464 { 2465 int error = 0; 2466 struct ng_mesg *msg; 2467 struct ng_mesg *resp = NULL; 2468 2469 NGI_GET_MSG(item, msg); 2470 if (msg->header.typecookie != NGM_GENERIC_COOKIE) { 2471 TRAP_ERROR(); 2472 error = EINVAL; 2473 goto out; 2474 } 2475 switch (msg->header.cmd) { 2476 case NGM_SHUTDOWN: 2477 ng_rmnode(here, NULL, NULL, 0); 2478 break; 2479 case NGM_MKPEER: 2480 { 2481 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data; 2482 2483 if (msg->header.arglen != sizeof(*mkp)) { 2484 TRAP_ERROR(); 2485 error = EINVAL; 2486 break; 2487 } 2488 mkp->type[sizeof(mkp->type) - 1] = '\0'; 2489 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0'; 2490 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0'; 2491 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type); 2492 break; 2493 } 2494 case NGM_CONNECT: 2495 { 2496 struct ngm_connect *const con = 2497 (struct ngm_connect *) msg->data; 2498 node_p node2; 2499 2500 if (msg->header.arglen != sizeof(*con)) { 2501 TRAP_ERROR(); 2502 error = EINVAL; 2503 break; 2504 } 2505 con->path[sizeof(con->path) - 1] = '\0'; 2506 con->ourhook[sizeof(con->ourhook) - 1] = '\0'; 2507 con->peerhook[sizeof(con->peerhook) - 1] = '\0'; 2508 /* Don't forget we get a reference.. */ 2509 error = ng_path2noderef(here, con->path, &node2, NULL); 2510 if (error) 2511 break; 2512 error = ng_con_nodes(here, con->ourhook, node2, con->peerhook); 2513 NG_NODE_UNREF(node2); 2514 break; 2515 } 2516 case NGM_NAME: 2517 { 2518 struct ngm_name *const nam = (struct ngm_name *) msg->data; 2519 2520 if (msg->header.arglen != sizeof(*nam)) { 2521 TRAP_ERROR(); 2522 error = EINVAL; 2523 break; 2524 } 2525 nam->name[sizeof(nam->name) - 1] = '\0'; 2526 error = ng_name_node(here, nam->name); 2527 break; 2528 } 2529 case NGM_RMHOOK: 2530 { 2531 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data; 2532 hook_p hook; 2533 2534 if (msg->header.arglen != sizeof(*rmh)) { 2535 TRAP_ERROR(); 2536 error = EINVAL; 2537 break; 2538 } 2539 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0'; 2540 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL) 2541 ng_destroy_hook(hook); 2542 break; 2543 } 2544 case NGM_NODEINFO: 2545 { 2546 struct nodeinfo *ni; 2547 2548 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT); 2549 if (resp == NULL) { 2550 error = ENOMEM; 2551 break; 2552 } 2553 2554 /* Fill in node info */ 2555 ni = (struct nodeinfo *) resp->data; 2556 if (NG_NODE_HAS_NAME(here)) 2557 strncpy(ni->name, NG_NODE_NAME(here), NG_NODELEN); 2558 strncpy(ni->type, here->nd_type->name, NG_TYPELEN); 2559 ni->id = ng_node2ID(here); 2560 ni->hooks = here->nd_numhooks; 2561 break; 2562 } 2563 case NGM_LISTHOOKS: 2564 { 2565 const int nhooks = here->nd_numhooks; 2566 struct hooklist *hl; 2567 struct nodeinfo *ni; 2568 hook_p hook; 2569 2570 /* Get response struct */ 2571 NG_MKRESPONSE(resp, msg, sizeof(*hl) 2572 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT); 2573 if (resp == NULL) { 2574 error = ENOMEM; 2575 break; 2576 } 2577 hl = (struct hooklist *) resp->data; 2578 ni = &hl->nodeinfo; 2579 2580 /* Fill in node info */ 2581 if (NG_NODE_HAS_NAME(here)) 2582 strncpy(ni->name, NG_NODE_NAME(here), NG_NODELEN); 2583 strncpy(ni->type, here->nd_type->name, NG_TYPELEN); 2584 ni->id = ng_node2ID(here); 2585 2586 /* Cycle through the linked list of hooks */ 2587 ni->hooks = 0; 2588 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) { 2589 struct linkinfo *const link = &hl->link[ni->hooks]; 2590 2591 if (ni->hooks >= nhooks) { 2592 log(LOG_ERR, "%s: number of %s changed\n", 2593 __func__, "hooks"); 2594 break; 2595 } 2596 if (NG_HOOK_NOT_VALID(hook)) 2597 continue; 2598 strncpy(link->ourhook, NG_HOOK_NAME(hook), NG_HOOKLEN); 2599 strncpy(link->peerhook, 2600 NG_PEER_HOOK_NAME(hook), NG_HOOKLEN); 2601 if (NG_PEER_NODE_NAME(hook)[0] != '\0') 2602 strncpy(link->nodeinfo.name, 2603 NG_PEER_NODE_NAME(hook), NG_NODELEN); 2604 strncpy(link->nodeinfo.type, 2605 NG_PEER_NODE(hook)->nd_type->name, NG_TYPELEN); 2606 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook)); 2607 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks; 2608 ni->hooks++; 2609 } 2610 break; 2611 } 2612 2613 case NGM_LISTNAMES: 2614 case NGM_LISTNODES: 2615 { 2616 const int unnamed = (msg->header.cmd == NGM_LISTNODES); 2617 struct namelist *nl; 2618 node_p node; 2619 int num = 0; 2620 2621 mtx_lock(&ng_nodelist_mtx); 2622 /* Count number of nodes */ 2623 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2624 if (NG_NODE_IS_VALID(node) 2625 && (unnamed || NG_NODE_HAS_NAME(node))) { 2626 num++; 2627 } 2628 } 2629 mtx_unlock(&ng_nodelist_mtx); 2630 2631 /* Get response struct */ 2632 NG_MKRESPONSE(resp, msg, sizeof(*nl) 2633 + (num * sizeof(struct nodeinfo)), M_NOWAIT); 2634 if (resp == NULL) { 2635 error = ENOMEM; 2636 break; 2637 } 2638 nl = (struct namelist *) resp->data; 2639 2640 /* Cycle through the linked list of nodes */ 2641 nl->numnames = 0; 2642 mtx_lock(&ng_nodelist_mtx); 2643 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2644 struct nodeinfo *const np = &nl->nodeinfo[nl->numnames]; 2645 2646 if (nl->numnames >= num) { 2647 log(LOG_ERR, "%s: number of %s changed\n", 2648 __func__, "nodes"); 2649 break; 2650 } 2651 if (NG_NODE_NOT_VALID(node)) 2652 continue; 2653 if (!unnamed && (! NG_NODE_HAS_NAME(node))) 2654 continue; 2655 if (NG_NODE_HAS_NAME(node)) 2656 strncpy(np->name, NG_NODE_NAME(node), NG_NODELEN); 2657 strncpy(np->type, node->nd_type->name, NG_TYPELEN); 2658 np->id = ng_node2ID(node); 2659 np->hooks = node->nd_numhooks; 2660 nl->numnames++; 2661 } 2662 mtx_unlock(&ng_nodelist_mtx); 2663 break; 2664 } 2665 2666 case NGM_LISTTYPES: 2667 { 2668 struct typelist *tl; 2669 struct ng_type *type; 2670 int num = 0; 2671 2672 mtx_lock(&ng_typelist_mtx); 2673 /* Count number of types */ 2674 LIST_FOREACH(type, &ng_typelist, types) { 2675 num++; 2676 } 2677 mtx_unlock(&ng_typelist_mtx); 2678 2679 /* Get response struct */ 2680 NG_MKRESPONSE(resp, msg, sizeof(*tl) 2681 + (num * sizeof(struct typeinfo)), M_NOWAIT); 2682 if (resp == NULL) { 2683 error = ENOMEM; 2684 break; 2685 } 2686 tl = (struct typelist *) resp->data; 2687 2688 /* Cycle through the linked list of types */ 2689 tl->numtypes = 0; 2690 mtx_lock(&ng_typelist_mtx); 2691 LIST_FOREACH(type, &ng_typelist, types) { 2692 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes]; 2693 2694 if (tl->numtypes >= num) { 2695 log(LOG_ERR, "%s: number of %s changed\n", 2696 __func__, "types"); 2697 break; 2698 } 2699 strncpy(tp->type_name, type->name, NG_TYPELEN); 2700 tp->numnodes = type->refs - 1; /* don't count list */ 2701 tl->numtypes++; 2702 } 2703 mtx_unlock(&ng_typelist_mtx); 2704 break; 2705 } 2706 2707 case NGM_BINARY2ASCII: 2708 { 2709 int bufSize = 20 * 1024; /* XXX hard coded constant */ 2710 const struct ng_parse_type *argstype; 2711 const struct ng_cmdlist *c; 2712 struct ng_mesg *binary, *ascii; 2713 2714 /* Data area must contain a valid netgraph message */ 2715 binary = (struct ng_mesg *)msg->data; 2716 if (msg->header.arglen < sizeof(struct ng_mesg) 2717 || (msg->header.arglen - sizeof(struct ng_mesg) 2718 < binary->header.arglen)) { 2719 TRAP_ERROR(); 2720 error = EINVAL; 2721 break; 2722 } 2723 2724 /* Get a response message with lots of room */ 2725 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT); 2726 if (resp == NULL) { 2727 error = ENOMEM; 2728 break; 2729 } 2730 ascii = (struct ng_mesg *)resp->data; 2731 2732 /* Copy binary message header to response message payload */ 2733 bcopy(binary, ascii, sizeof(*binary)); 2734 2735 /* Find command by matching typecookie and command number */ 2736 for (c = here->nd_type->cmdlist; 2737 c != NULL && c->name != NULL; c++) { 2738 if (binary->header.typecookie == c->cookie 2739 && binary->header.cmd == c->cmd) 2740 break; 2741 } 2742 if (c == NULL || c->name == NULL) { 2743 for (c = ng_generic_cmds; c->name != NULL; c++) { 2744 if (binary->header.typecookie == c->cookie 2745 && binary->header.cmd == c->cmd) 2746 break; 2747 } 2748 if (c->name == NULL) { 2749 NG_FREE_MSG(resp); 2750 error = ENOSYS; 2751 break; 2752 } 2753 } 2754 2755 /* Convert command name to ASCII */ 2756 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr), 2757 "%s", c->name); 2758 2759 /* Convert command arguments to ASCII */ 2760 argstype = (binary->header.flags & NGF_RESP) ? 2761 c->respType : c->mesgType; 2762 if (argstype == NULL) { 2763 *ascii->data = '\0'; 2764 } else { 2765 if ((error = ng_unparse(argstype, 2766 (u_char *)binary->data, 2767 ascii->data, bufSize)) != 0) { 2768 NG_FREE_MSG(resp); 2769 break; 2770 } 2771 } 2772 2773 /* Return the result as struct ng_mesg plus ASCII string */ 2774 bufSize = strlen(ascii->data) + 1; 2775 ascii->header.arglen = bufSize; 2776 resp->header.arglen = sizeof(*ascii) + bufSize; 2777 break; 2778 } 2779 2780 case NGM_ASCII2BINARY: 2781 { 2782 int bufSize = 2000; /* XXX hard coded constant */ 2783 const struct ng_cmdlist *c; 2784 const struct ng_parse_type *argstype; 2785 struct ng_mesg *ascii, *binary; 2786 int off = 0; 2787 2788 /* Data area must contain at least a struct ng_mesg + '\0' */ 2789 ascii = (struct ng_mesg *)msg->data; 2790 if ((msg->header.arglen < sizeof(*ascii) + 1) 2791 || (ascii->header.arglen < 1) 2792 || (msg->header.arglen 2793 < sizeof(*ascii) + ascii->header.arglen)) { 2794 TRAP_ERROR(); 2795 error = EINVAL; 2796 break; 2797 } 2798 ascii->data[ascii->header.arglen - 1] = '\0'; 2799 2800 /* Get a response message with lots of room */ 2801 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT); 2802 if (resp == NULL) { 2803 error = ENOMEM; 2804 break; 2805 } 2806 binary = (struct ng_mesg *)resp->data; 2807 2808 /* Copy ASCII message header to response message payload */ 2809 bcopy(ascii, binary, sizeof(*ascii)); 2810 2811 /* Find command by matching ASCII command string */ 2812 for (c = here->nd_type->cmdlist; 2813 c != NULL && c->name != NULL; c++) { 2814 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2815 break; 2816 } 2817 if (c == NULL || c->name == NULL) { 2818 for (c = ng_generic_cmds; c->name != NULL; c++) { 2819 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2820 break; 2821 } 2822 if (c->name == NULL) { 2823 NG_FREE_MSG(resp); 2824 error = ENOSYS; 2825 break; 2826 } 2827 } 2828 2829 /* Convert command name to binary */ 2830 binary->header.cmd = c->cmd; 2831 binary->header.typecookie = c->cookie; 2832 2833 /* Convert command arguments to binary */ 2834 argstype = (binary->header.flags & NGF_RESP) ? 2835 c->respType : c->mesgType; 2836 if (argstype == NULL) { 2837 bufSize = 0; 2838 } else { 2839 if ((error = ng_parse(argstype, ascii->data, 2840 &off, (u_char *)binary->data, &bufSize)) != 0) { 2841 NG_FREE_MSG(resp); 2842 break; 2843 } 2844 } 2845 2846 /* Return the result */ 2847 binary->header.arglen = bufSize; 2848 resp->header.arglen = sizeof(*binary) + bufSize; 2849 break; 2850 } 2851 2852 case NGM_TEXT_CONFIG: 2853 case NGM_TEXT_STATUS: 2854 /* 2855 * This one is tricky as it passes the command down to the 2856 * actual node, even though it is a generic type command. 2857 * This means we must assume that the item/msg is already freed 2858 * when control passes back to us. 2859 */ 2860 if (here->nd_type->rcvmsg != NULL) { 2861 NGI_MSG(item) = msg; /* put it back as we found it */ 2862 return((*here->nd_type->rcvmsg)(here, item, lasthook)); 2863 } 2864 /* Fall through if rcvmsg not supported */ 2865 default: 2866 TRAP_ERROR(); 2867 error = EINVAL; 2868 } 2869 /* 2870 * Sometimes a generic message may be statically allocated 2871 * to avoid problems with allocating when in tight memeory situations. 2872 * Don't free it if it is so. 2873 * I break them appart here, because erros may cause a free if the item 2874 * in which case we'd be doing it twice. 2875 * they are kept together above, to simplify freeing. 2876 */ 2877 out: 2878 NG_RESPOND_MSG(error, here, item, resp); 2879 if (msg) 2880 NG_FREE_MSG(msg); 2881 return (error); 2882 } 2883 2884 /* 2885 * Copy a 'meta'. 2886 * 2887 * Returns new meta, or NULL if original meta is NULL or ENOMEM. 2888 */ 2889 meta_p 2890 ng_copy_meta(meta_p meta) 2891 { 2892 meta_p meta2; 2893 2894 if (meta == NULL) 2895 return (NULL); 2896 MALLOC(meta2, meta_p, meta->used_len, M_NETGRAPH_META, M_NOWAIT); 2897 if (meta2 == NULL) 2898 return (NULL); 2899 meta2->allocated_len = meta->used_len; 2900 bcopy(meta, meta2, meta->used_len); 2901 return (meta2); 2902 } 2903 2904 /************************************************************************ 2905 Module routines 2906 ************************************************************************/ 2907 2908 /* 2909 * Handle the loading/unloading of a netgraph node type module 2910 */ 2911 int 2912 ng_mod_event(module_t mod, int event, void *data) 2913 { 2914 struct ng_type *const type = data; 2915 int s, error = 0; 2916 2917 switch (event) { 2918 case MOD_LOAD: 2919 2920 /* Register new netgraph node type */ 2921 s = splnet(); 2922 if ((error = ng_newtype(type)) != 0) { 2923 splx(s); 2924 break; 2925 } 2926 2927 /* Call type specific code */ 2928 if (type->mod_event != NULL) 2929 if ((error = (*type->mod_event)(mod, event, data))) { 2930 mtx_lock(&ng_typelist_mtx); 2931 type->refs--; /* undo it */ 2932 LIST_REMOVE(type, types); 2933 mtx_unlock(&ng_typelist_mtx); 2934 } 2935 splx(s); 2936 break; 2937 2938 case MOD_UNLOAD: 2939 s = splnet(); 2940 if (type->refs > 1) { /* make sure no nodes exist! */ 2941 error = EBUSY; 2942 } else { 2943 if (type->refs == 0) { 2944 /* failed load, nothing to undo */ 2945 splx(s); 2946 break; 2947 } 2948 if (type->mod_event != NULL) { /* check with type */ 2949 error = (*type->mod_event)(mod, event, data); 2950 if (error != 0) { /* type refuses.. */ 2951 splx(s); 2952 break; 2953 } 2954 } 2955 mtx_lock(&ng_typelist_mtx); 2956 LIST_REMOVE(type, types); 2957 mtx_unlock(&ng_typelist_mtx); 2958 } 2959 splx(s); 2960 break; 2961 2962 default: 2963 if (type->mod_event != NULL) 2964 error = (*type->mod_event)(mod, event, data); 2965 else 2966 error = 0; /* XXX ? */ 2967 break; 2968 } 2969 return (error); 2970 } 2971 2972 /* 2973 * Handle loading and unloading for this code. 2974 * The only thing we need to link into is the NETISR strucure. 2975 */ 2976 static int 2977 ngb_mod_event(module_t mod, int event, void *data) 2978 { 2979 int s, error = 0; 2980 2981 switch (event) { 2982 case MOD_LOAD: 2983 /* Register line discipline */ 2984 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_SPIN); 2985 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL, 0); 2986 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL, 0); 2987 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL, 0); 2988 mtx_init(&ngq_mtx, "netgraph netisr mutex", NULL, 0); 2989 s = splimp(); 2990 error = register_netisr(NETISR_NETGRAPH, ngintr); 2991 splx(s); 2992 break; 2993 case MOD_UNLOAD: 2994 /* You cant unload it because an interface may be using it. */ 2995 error = EBUSY; 2996 break; 2997 default: 2998 error = EOPNOTSUPP; 2999 break; 3000 } 3001 return (error); 3002 } 3003 3004 static moduledata_t netgraph_mod = { 3005 "netgraph", 3006 ngb_mod_event, 3007 (NULL) 3008 }; 3009 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE); 3010 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family"); 3011 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,""); 3012 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, ""); 3013 3014 /************************************************************************ 3015 Queue element get/free routines 3016 ************************************************************************/ 3017 3018 3019 static int allocated; /* number of items malloc'd */ 3020 static int maxalloc = 128; /* limit the damage of a leak */ 3021 static const int ngqfreemax = 64;/* cache at most this many */ 3022 static const int ngqfreelow = 4; /* try malloc if free < this */ 3023 static volatile int ngqfreesize; /* number of cached entries */ 3024 #ifdef NETGRAPH_DEBUG 3025 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist); 3026 #endif 3027 /* 3028 * Get a queue entry 3029 * This is usually called when a packet first enters netgraph. 3030 * By definition, this is usually from an interrupt, or from a user. 3031 * Users are not so important, but try be quick for the times that it's 3032 * an interrupt. Use atomic operations to cope with collisions 3033 * with interrupts and other processors. Assumes MALLOC is SMP safe. 3034 * XXX If reserve is low, we should try to get 2 from malloc as this 3035 * would indicate it often fails. 3036 */ 3037 static item_p 3038 ng_getqblk(void) 3039 { 3040 item_p item = NULL; 3041 3042 /* 3043 * Try get a cached queue block, or else allocate a new one 3044 * If we are less than our reserve, try malloc. If malloc 3045 * fails, then that's what the reserve is for... 3046 * Don't completely trust ngqfreesize, as it is subject 3047 * to races.. (it'll eventually catch up but may be out by one or two 3048 * for brief moments(under SMP or interrupts). 3049 * ngqfree is the final arbiter. We have our little reserve 3050 * because we use M_NOWAIT for malloc. This just helps us 3051 * avoid dropping packets while not increasing the time 3052 * we take to service the interrupt (on average) (I hope). 3053 */ 3054 for (;;) { 3055 if ((ngqfreesize < ngqfreelow) || (ngqfree == NULL)) { 3056 if (allocated < maxalloc) { /* don't leak forever */ 3057 MALLOC(item, item_p , 3058 sizeof(*item), M_NETGRAPH_ITEM, 3059 (M_NOWAIT | M_ZERO)); 3060 if (item) { 3061 #ifdef NETGRAPH_DEBUG 3062 TAILQ_INSERT_TAIL(&ng_itemlist, 3063 item, all); 3064 #endif /* NETGRAPH_DEBUG */ 3065 atomic_add_int(&allocated, 1); 3066 break; 3067 } 3068 } 3069 } 3070 3071 /* 3072 * We didn't or couldn't malloc. 3073 * try get one from our cache. 3074 * item must be NULL to get here. 3075 */ 3076 if ((item = ngqfree) != NULL) { 3077 /* 3078 * Atomically try grab the first item 3079 * and put it's successor in its place. 3080 * If we fail, just try again.. someone else 3081 * beat us to this one or freed one. 3082 * Don't worry about races with ngqfreesize. 3083 * Close enough is good enough.. 3084 */ 3085 if (atomic_cmpset_ptr(&ngqfree, item, item->el_next)) { 3086 atomic_subtract_int(&ngqfreesize, 1); 3087 item->el_flags &= ~NGQF_FREE; 3088 break; 3089 } 3090 /* 3091 * something got there before we did.. try again 3092 * (go around the loop again) 3093 */ 3094 item = NULL; 3095 } else { 3096 /* We really ran out */ 3097 break; 3098 } 3099 } 3100 return (item); 3101 } 3102 3103 /* 3104 * Release a queue entry 3105 */ 3106 void 3107 ng_free_item(item_p item) 3108 { 3109 3110 /* 3111 * The item may hold resources on it's own. We need to free 3112 * these before we can free the item. What they are depends upon 3113 * what kind of item it is. it is important that nodes zero 3114 * out pointers to resources that they remove from the item 3115 * or we release them again here. 3116 */ 3117 if (item->el_flags & NGQF_FREE) { 3118 panic(" Freeing free queue item"); 3119 } 3120 switch (item->el_flags & NGQF_TYPE) { 3121 case NGQF_DATA: 3122 /* If we have an mbuf and metadata still attached.. */ 3123 NG_FREE_M(_NGI_M(item)); 3124 NG_FREE_META(_NGI_META(item)); 3125 break; 3126 case NGQF_MESG: 3127 _NGI_RETADDR(item) = 0; 3128 NG_FREE_MSG(_NGI_MSG(item)); 3129 break; 3130 case NGQF_FN: 3131 /* nothing to free really, */ 3132 _NGI_FN(item) = NULL; 3133 _NGI_ARG1(item) = NULL; 3134 _NGI_ARG2(item) = 0; 3135 case NGQF_UNDEF: 3136 break; 3137 } 3138 /* If we still have a node or hook referenced... */ 3139 _NGI_CLR_NODE(item); 3140 _NGI_CLR_HOOK(item); 3141 item->el_flags |= NGQF_FREE; 3142 3143 /* 3144 * We have freed any resources held by the item. 3145 * now we can free the item itself. 3146 */ 3147 if (ngqfreesize < ngqfreemax) { /* don't worry about races */ 3148 for (;;) { 3149 item->el_next = ngqfree; 3150 if (atomic_cmpset_ptr(&ngqfree, item->el_next, item)) { 3151 break; 3152 } 3153 } 3154 atomic_add_int(&ngqfreesize, 1); 3155 } else { 3156 /* This is the only place that should use this Macro */ 3157 #ifdef NETGRAPH_DEBUG 3158 TAILQ_REMOVE(&ng_itemlist, item, all); 3159 #endif /* NETGRAPH_DEBUG */ 3160 NG_FREE_ITEM_REAL(item); 3161 atomic_subtract_int(&allocated, 1); 3162 } 3163 } 3164 3165 #ifdef NETGRAPH_DEBUG 3166 void 3167 dumphook (hook_p hook, char *file, int line) 3168 { 3169 printf("hook: name %s, %d refs, Last touched:\n", 3170 _NG_HOOK_NAME(hook), hook->hk_refs); 3171 printf(" Last active @ %s, line %d\n", 3172 hook->lastfile, hook->lastline); 3173 if (line) { 3174 printf(" problem discovered at file %s, line %d\n", file, line); 3175 } 3176 } 3177 3178 void 3179 dumpnode(node_p node, char *file, int line) 3180 { 3181 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n", 3182 _NG_NODE_ID(node), node->nd_type->name, 3183 node->nd_numhooks, node->nd_flags, 3184 node->nd_refs, node->nd_name); 3185 printf(" Last active @ %s, line %d\n", 3186 node->lastfile, node->lastline); 3187 if (line) { 3188 printf(" problem discovered at file %s, line %d\n", file, line); 3189 } 3190 } 3191 3192 void 3193 dumpitem(item_p item, char *file, int line) 3194 { 3195 if (item->el_flags & NGQF_FREE) { 3196 printf(" Free item, freed at %s, line %d\n", 3197 item->lastfile, item->lastline); 3198 } else { 3199 printf(" ACTIVE item, last used at %s, line %d", 3200 item->lastfile, item->lastline); 3201 switch(item->el_flags & NGQF_TYPE) { 3202 case NGQF_DATA: 3203 printf(" - [data]\n"); 3204 break; 3205 case NGQF_MESG: 3206 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item)); 3207 break; 3208 case NGQF_FN: 3209 printf(" - fn@%p (%p, %p, %p, %d (%x))\n", 3210 item->body.fn.fn_fn, 3211 NGI_NODE(item), 3212 NGI_HOOK(item), 3213 item->body.fn.fn_arg1, 3214 item->body.fn.fn_arg2, 3215 item->body.fn.fn_arg2); 3216 break; 3217 case NGQF_UNDEF: 3218 printf(" - UNDEFINED!\n"); 3219 } 3220 } 3221 if (line) { 3222 printf(" problem discovered at file %s, line %d\n", file, line); 3223 if (NGI_NODE(item)) { 3224 printf("node %p ([%x])\n", 3225 NGI_NODE(item), ng_node2ID(NGI_NODE(item))); 3226 } 3227 } 3228 } 3229 3230 static void 3231 ng_dumpitems(void) 3232 { 3233 item_p item; 3234 int i = 1; 3235 TAILQ_FOREACH(item, &ng_itemlist, all) { 3236 printf("[%d] ", i++); 3237 dumpitem(item, NULL, 0); 3238 } 3239 } 3240 3241 static void 3242 ng_dumpnodes(void) 3243 { 3244 node_p node; 3245 int i = 1; 3246 SLIST_FOREACH(node, &ng_allnodes, nd_all) { 3247 printf("[%d] ", i++); 3248 dumpnode(node, NULL, 0); 3249 } 3250 } 3251 3252 static void 3253 ng_dumphooks(void) 3254 { 3255 hook_p hook; 3256 int i = 1; 3257 SLIST_FOREACH(hook, &ng_allhooks, hk_all) { 3258 printf("[%d] ", i++); 3259 dumphook(hook, NULL, 0); 3260 } 3261 } 3262 3263 static int 3264 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS) 3265 { 3266 int error; 3267 int val; 3268 int i; 3269 3270 val = allocated; 3271 i = 1; 3272 error = sysctl_handle_int(oidp, &val, sizeof(int), req); 3273 if (error != 0 || req->newptr == NULL) 3274 return (error); 3275 if (val == 42) { 3276 ng_dumpitems(); 3277 ng_dumpnodes(); 3278 ng_dumphooks(); 3279 } 3280 return (0); 3281 } 3282 3283 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW, 3284 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items"); 3285 #endif /* NETGRAPH_DEBUG */ 3286 3287 3288 /*********************************************************************** 3289 * Worklist routines 3290 **********************************************************************/ 3291 /* NETISR thread enters here */ 3292 /* 3293 * Pick a node off the list of nodes with work, 3294 * try get an item to process off it. 3295 * If there are no more, remove the node from the list. 3296 */ 3297 static void 3298 ngintr(void) 3299 { 3300 item_p item; 3301 node_p node = NULL; 3302 3303 for (;;) { 3304 mtx_lock_spin(&ng_worklist_mtx); 3305 node = TAILQ_FIRST(&ng_worklist); 3306 if (!node) { 3307 mtx_unlock_spin(&ng_worklist_mtx); 3308 break; 3309 } 3310 node->nd_flags &= ~NG_WORKQ; 3311 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3312 mtx_unlock_spin(&ng_worklist_mtx); 3313 /* 3314 * We have the node. We also take over the reference 3315 * that the list had on it. 3316 * Now process as much as you can, until it won't 3317 * let you have another item off the queue. 3318 * All this time, keep the reference 3319 * that lets us be sure that the node still exists. 3320 * Let the reference go at the last minute. 3321 * ng_dequeue will put us back on the worklist 3322 * if there is more too do. This may be of use if there 3323 * are Multiple Processors and multiple Net threads in the 3324 * future. 3325 */ 3326 for (;;) { 3327 mtx_lock_spin(&node->nd_input_queue.q_mtx); 3328 item = ng_dequeue(&node->nd_input_queue); 3329 if (item == NULL) { 3330 mtx_unlock_spin(&node->nd_input_queue.q_mtx); 3331 break; /* go look for another node */ 3332 } else { 3333 mtx_unlock_spin(&node->nd_input_queue.q_mtx); 3334 NGI_GET_NODE(item, node); /* zaps stored node */ 3335 ng_apply_item(node, item); 3336 NG_NODE_UNREF(node); 3337 } 3338 } 3339 NG_NODE_UNREF(node); 3340 } 3341 } 3342 3343 static void 3344 ng_worklist_remove(node_p node) 3345 { 3346 mtx_lock_spin(&ng_worklist_mtx); 3347 if (node->nd_flags & NG_WORKQ) { 3348 node->nd_flags &= ~NG_WORKQ; 3349 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3350 mtx_unlock_spin(&ng_worklist_mtx); 3351 NG_NODE_UNREF(node); 3352 } else { 3353 mtx_unlock_spin(&ng_worklist_mtx); 3354 } 3355 } 3356 3357 /* 3358 * XXX 3359 * It's posible that a debugging NG_NODE_REF may need 3360 * to be outside the mutex zone 3361 */ 3362 static void 3363 ng_setisr(node_p node) 3364 { 3365 mtx_lock_spin(&ng_worklist_mtx); 3366 if ((node->nd_flags & NG_WORKQ) == 0) { 3367 /* 3368 * If we are not already on the work queue, 3369 * then put us on. 3370 */ 3371 node->nd_flags |= NG_WORKQ; 3372 TAILQ_INSERT_TAIL(&ng_worklist, node, nd_work); 3373 NG_NODE_REF(node); /* XXX fafe in mutex? */ 3374 } 3375 mtx_unlock_spin(&ng_worklist_mtx); 3376 schednetisr(NETISR_NETGRAPH); 3377 } 3378 3379 3380 /*********************************************************************** 3381 * Externally useable functions to set up a queue item ready for sending 3382 ***********************************************************************/ 3383 3384 #ifdef NETGRAPH_DEBUG 3385 #define ITEM_DEBUG_CHECKS \ 3386 do { \ 3387 if (NGI_NODE(item) ) { \ 3388 printf("item already has node"); \ 3389 Debugger("has node"); \ 3390 NGI_CLR_NODE(item); \ 3391 } \ 3392 if (NGI_HOOK(item) ) { \ 3393 printf("item already has hook"); \ 3394 Debugger("has hook"); \ 3395 NGI_CLR_HOOK(item); \ 3396 } \ 3397 } while (0) 3398 #else 3399 #define ITEM_DEBUG_CHECKS 3400 #endif 3401 3402 /* 3403 * Put elements into the item. 3404 * Hook and node references will be removed when the item is dequeued. 3405 * (or equivalent) 3406 * (XXX) Unsafe because no reference held by peer on remote node. 3407 * remote node might go away in this timescale. 3408 * We know the hooks can't go away because that would require getting 3409 * a writer item on both nodes and we must have at least a reader 3410 * here to eb able to do this. 3411 * Note that the hook loaded is the REMOTE hook. 3412 * 3413 * This is possibly in the critical path for new data. 3414 */ 3415 item_p 3416 ng_package_data(struct mbuf *m, meta_p meta) 3417 { 3418 item_p item; 3419 3420 if ((item = ng_getqblk()) == NULL) { 3421 NG_FREE_M(m); 3422 NG_FREE_META(meta); 3423 return (NULL); 3424 } 3425 ITEM_DEBUG_CHECKS; 3426 item->el_flags = NGQF_DATA; 3427 item->el_next = NULL; 3428 NGI_M(item) = m; 3429 NGI_META(item) = meta; 3430 return (item); 3431 } 3432 3433 /* 3434 * Allocate a queue item and put items into it.. 3435 * Evaluate the address as this will be needed to queue it and 3436 * to work out what some of the fields should be. 3437 * Hook and node references will be removed when the item is dequeued. 3438 * (or equivalent) 3439 */ 3440 item_p 3441 ng_package_msg(struct ng_mesg *msg) 3442 { 3443 item_p item; 3444 3445 if ((item = ng_getqblk()) == NULL) { 3446 NG_FREE_MSG(msg); 3447 return (NULL); 3448 } 3449 ITEM_DEBUG_CHECKS; 3450 item->el_flags = NGQF_MESG; 3451 item->el_next = NULL; 3452 /* 3453 * Set the current lasthook into the queue item 3454 */ 3455 NGI_MSG(item) = msg; 3456 NGI_RETADDR(item) = 0; 3457 return (item); 3458 } 3459 3460 3461 3462 #define SET_RETADDR(item, here, retaddr) \ 3463 do { /* Data or fn items don't have retaddrs */ \ 3464 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \ 3465 if (retaddr) { \ 3466 NGI_RETADDR(item) = retaddr; \ 3467 } else { \ 3468 /* \ 3469 * The old return address should be ok. \ 3470 * If there isn't one, use the address \ 3471 * here. \ 3472 */ \ 3473 if (NGI_RETADDR(item) == 0) { \ 3474 NGI_RETADDR(item) \ 3475 = ng_node2ID(here); \ 3476 } \ 3477 } \ 3478 } \ 3479 } while (0) 3480 3481 int 3482 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr) 3483 { 3484 hook_p peer; 3485 node_p peernode; 3486 ITEM_DEBUG_CHECKS; 3487 /* 3488 * Quick sanity check.. 3489 * Since a hook holds a reference on it's node, once we know 3490 * that the peer is still connected (even if invalid,) we know 3491 * that the peer node is present, though maybe invalid. 3492 */ 3493 if ((hook == NULL) 3494 || NG_HOOK_NOT_VALID(hook) 3495 || (NG_HOOK_PEER(hook) == NULL) 3496 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)) 3497 || NG_NODE_NOT_VALID(NG_PEER_NODE(hook))) { 3498 NG_FREE_ITEM(item); 3499 TRAP_ERROR(); 3500 return (ENETDOWN); 3501 } 3502 3503 /* 3504 * Transfer our interest to the other (peer) end. 3505 */ 3506 peer = NG_HOOK_PEER(hook); 3507 NG_HOOK_REF(peer); 3508 NGI_SET_HOOK(item, peer); 3509 peernode = NG_PEER_NODE(hook); 3510 NG_NODE_REF(peernode); 3511 NGI_SET_NODE(item, peernode); 3512 SET_RETADDR(item, here, retaddr); 3513 return (0); 3514 } 3515 3516 int 3517 ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr) 3518 { 3519 node_p dest = NULL; 3520 hook_p hook = NULL; 3521 int error; 3522 3523 ITEM_DEBUG_CHECKS; 3524 /* 3525 * Note that ng_path2noderef increments the reference count 3526 * on the node for us if it finds one. So we don't have to. 3527 */ 3528 error = ng_path2noderef(here, address, &dest, &hook); 3529 if (error) { 3530 NG_FREE_ITEM(item); 3531 return (error); 3532 } 3533 NGI_SET_NODE(item, dest); 3534 if ( hook) { 3535 NG_HOOK_REF(hook); /* don't let it go while on the queue */ 3536 NGI_SET_HOOK(item, hook); 3537 } 3538 SET_RETADDR(item, here, retaddr); 3539 return (0); 3540 } 3541 3542 int 3543 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr) 3544 { 3545 node_p dest; 3546 3547 ITEM_DEBUG_CHECKS; 3548 /* 3549 * Find the target node. 3550 */ 3551 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */ 3552 if (dest == NULL) { 3553 NG_FREE_ITEM(item); 3554 TRAP_ERROR(); 3555 return(EINVAL); 3556 } 3557 /* Fill out the contents */ 3558 item->el_flags = NGQF_MESG; 3559 item->el_next = NULL; 3560 NGI_SET_NODE(item, dest); 3561 NGI_CLR_HOOK(item); 3562 SET_RETADDR(item, here, retaddr); 3563 return (0); 3564 } 3565 3566 /* 3567 * special case to send a message to self (e.g. destroy node) 3568 * Possibly indicate an arrival hook too. 3569 * Useful for removing that hook :-) 3570 */ 3571 item_p 3572 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg) 3573 { 3574 item_p item; 3575 3576 /* 3577 * Find the target node. 3578 * If there is a HOOK argument, then use that in preference 3579 * to the address. 3580 */ 3581 if ((item = ng_getqblk()) == NULL) { 3582 NG_FREE_MSG(msg); 3583 return (NULL); 3584 } 3585 3586 /* Fill out the contents */ 3587 item->el_flags = NGQF_MESG; 3588 item->el_next = NULL; 3589 NG_NODE_REF(here); 3590 NGI_SET_NODE(item, here); 3591 if (hook) { 3592 NG_HOOK_REF(hook); 3593 NGI_SET_HOOK(item, hook); 3594 } 3595 NGI_MSG(item) = msg; 3596 NGI_RETADDR(item) = ng_node2ID(here); 3597 return (item); 3598 } 3599 3600 int 3601 ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2) 3602 { 3603 item_p item; 3604 3605 if ((item = ng_getqblk()) == NULL) { 3606 return (ENOMEM); 3607 } 3608 item->el_flags = NGQF_FN | NGQF_WRITER; 3609 NG_NODE_REF(node); /* and one for the item */ 3610 NGI_SET_NODE(item, node); 3611 if (hook) { 3612 NG_HOOK_REF(hook); 3613 NGI_SET_HOOK(item, hook); 3614 } 3615 NGI_FN(item) = fn; 3616 NGI_ARG1(item) = arg1; 3617 NGI_ARG2(item) = arg2; 3618 return(ng_snd_item(item, 0)); 3619 } 3620 3621 /* 3622 * Official timeout routines for Netgraph nodes. 3623 */ 3624 static void 3625 ng_timeout_trapoline(void *arg) 3626 { 3627 item_p item = arg; 3628 3629 ng_snd_item(item, 0); 3630 } 3631 3632 3633 struct callout_handle 3634 ng_timeout(node_p node, hook_p hook, int ticks, 3635 ng_item_fn *fn, void * arg1, int arg2) 3636 { 3637 item_p item; 3638 3639 if ((item = ng_getqblk()) == NULL) { 3640 struct callout_handle handle; 3641 handle.callout = NULL; 3642 return (handle); 3643 } 3644 item->el_flags = NGQF_FN | NGQF_WRITER; 3645 NG_NODE_REF(node); /* and one for the item */ 3646 NGI_SET_NODE(item, node); 3647 if (hook) { 3648 NG_HOOK_REF(hook); 3649 NGI_SET_HOOK(item, hook); 3650 } 3651 NGI_FN(item) = fn; 3652 NGI_ARG1(item) = arg1; 3653 NGI_ARG2(item) = arg2; 3654 return (timeout(&ng_timeout_trapoline, item, ticks)); 3655 } 3656 3657 /* A special modified version of untimeout() */ 3658 int 3659 ng_untimeout(struct callout_handle handle, node_p node) 3660 { 3661 item_p item; 3662 3663 if (handle.callout == NULL) 3664 return (0); 3665 mtx_lock_spin(&callout_lock); 3666 item = handle.callout->c_arg; /* should be an official way to do this */ 3667 if ((handle.callout->c_func == &ng_timeout_trapoline) && 3668 (NGI_NODE(item) == node) && 3669 (callout_stop(handle.callout))) { 3670 /* 3671 * We successfully removed it from the queue before it ran 3672 * So now we need to unreference everything that was 3673 * given extra references. (NG_FREE_ITEM does this). 3674 */ 3675 mtx_unlock_spin(&callout_lock); 3676 NG_FREE_ITEM(item); 3677 return (1); 3678 } 3679 mtx_unlock_spin(&callout_lock); 3680 return (0); 3681 } 3682 3683 /* 3684 * Set the address, if none given, give the node here. 3685 */ 3686 void 3687 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr) 3688 { 3689 if (retaddr) { 3690 NGI_RETADDR(item) = retaddr; 3691 } else { 3692 /* 3693 * The old return address should be ok. 3694 * If there isn't one, use the address here. 3695 */ 3696 NGI_RETADDR(item) = ng_node2ID(here); 3697 } 3698 } 3699 3700 #define TESTING 3701 #ifdef TESTING 3702 /* just test all the macros */ 3703 void 3704 ng_macro_test(item_p item); 3705 void 3706 ng_macro_test(item_p item) 3707 { 3708 node_p node = NULL; 3709 hook_p hook = NULL; 3710 struct mbuf *m; 3711 meta_p meta; 3712 struct ng_mesg *msg; 3713 ng_ID_t retaddr; 3714 int error; 3715 3716 NGI_GET_M(item, m); 3717 NGI_GET_META(item, meta); 3718 NGI_GET_MSG(item, msg); 3719 retaddr = NGI_RETADDR(item); 3720 NG_SEND_DATA(error, hook, m, meta); 3721 NG_SEND_DATA_ONLY(error, hook, m); 3722 NG_FWD_NEW_DATA(error, item, hook, m); 3723 NG_FWD_ITEM_HOOK(error, item, hook); 3724 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr); 3725 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr); 3726 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr); 3727 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr); 3728 } 3729 #endif /* TESTING */ 3730 3731