1 /* 2 * ng_base.c 3 */ 4 5 /*- 6 * Copyright (c) 1996-1999 Whistle Communications, Inc. 7 * All rights reserved. 8 * 9 * Subject to the following obligations and disclaimer of warranty, use and 10 * redistribution of this software, in source or object code forms, with or 11 * without modifications are expressly permitted by Whistle Communications; 12 * provided, however, that: 13 * 1. Any and all reproductions of the source or object code must include the 14 * copyright notice above and the following disclaimer of warranties; and 15 * 2. No rights are granted, in any manner or form, to use Whistle 16 * Communications, Inc. trademarks, including the mark "WHISTLE 17 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 18 * such appears in the above copyright notice or in the software. 19 * 20 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 21 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 22 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 23 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 25 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 26 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 27 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 28 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 29 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 30 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 31 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 32 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 35 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 36 * OF SUCH DAMAGE. 37 * 38 * Authors: Julian Elischer <julian@freebsd.org> 39 * Archie Cobbs <archie@freebsd.org> 40 * 41 * $FreeBSD$ 42 * $Whistle: ng_base.c,v 1.39 1999/01/28 23:54:53 julian Exp $ 43 */ 44 45 /* 46 * This file implements the base netgraph code. 47 */ 48 49 #include <sys/param.h> 50 #include <sys/systm.h> 51 #include <sys/ctype.h> 52 #include <sys/errno.h> 53 #include <sys/kdb.h> 54 #include <sys/kernel.h> 55 #include <sys/ktr.h> 56 #include <sys/limits.h> 57 #include <sys/malloc.h> 58 #include <sys/mbuf.h> 59 #include <sys/queue.h> 60 #include <sys/sysctl.h> 61 #include <sys/syslog.h> 62 63 #include <net/netisr.h> 64 65 #include <netgraph/ng_message.h> 66 #include <netgraph/netgraph.h> 67 #include <netgraph/ng_parse.h> 68 69 MODULE_VERSION(netgraph, NG_ABI_VERSION); 70 71 /* List of all active nodes */ 72 static LIST_HEAD(, ng_node) ng_nodelist; 73 static struct mtx ng_nodelist_mtx; 74 75 /* Mutex to protect topology events. */ 76 static struct mtx ng_topo_mtx; 77 78 #ifdef NETGRAPH_DEBUG 79 static struct mtx ngq_mtx; /* protects the queue item list */ 80 81 static SLIST_HEAD(, ng_node) ng_allnodes; 82 static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */ 83 static SLIST_HEAD(, ng_hook) ng_allhooks; 84 static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */ 85 86 static void ng_dumpitems(void); 87 static void ng_dumpnodes(void); 88 static void ng_dumphooks(void); 89 90 #endif /* NETGRAPH_DEBUG */ 91 /* 92 * DEAD versions of the structures. 93 * In order to avoid races, it is sometimes neccesary to point 94 * at SOMETHING even though theoretically, the current entity is 95 * INVALID. Use these to avoid these races. 96 */ 97 struct ng_type ng_deadtype = { 98 NG_ABI_VERSION, 99 "dead", 100 NULL, /* modevent */ 101 NULL, /* constructor */ 102 NULL, /* rcvmsg */ 103 NULL, /* shutdown */ 104 NULL, /* newhook */ 105 NULL, /* findhook */ 106 NULL, /* connect */ 107 NULL, /* rcvdata */ 108 NULL, /* disconnect */ 109 NULL, /* cmdlist */ 110 }; 111 112 struct ng_node ng_deadnode = { 113 "dead", 114 &ng_deadtype, 115 NGF_INVALID, 116 1, /* refs */ 117 0, /* numhooks */ 118 NULL, /* private */ 119 0, /* ID */ 120 LIST_HEAD_INITIALIZER(ng_deadnode.hooks), 121 {}, /* all_nodes list entry */ 122 {}, /* id hashtable list entry */ 123 {}, /* workqueue entry */ 124 { 0, 125 {}, /* should never use! (should hang) */ 126 NULL, 127 &ng_deadnode.nd_input_queue.queue, 128 &ng_deadnode 129 }, 130 #ifdef NETGRAPH_DEBUG 131 ND_MAGIC, 132 __FILE__, 133 __LINE__, 134 {NULL} 135 #endif /* NETGRAPH_DEBUG */ 136 }; 137 138 struct ng_hook ng_deadhook = { 139 "dead", 140 NULL, /* private */ 141 HK_INVALID | HK_DEAD, 142 1, /* refs always >= 1 */ 143 0, /* undefined data link type */ 144 &ng_deadhook, /* Peer is self */ 145 &ng_deadnode, /* attached to deadnode */ 146 {}, /* hooks list */ 147 NULL, /* override rcvmsg() */ 148 NULL, /* override rcvdata() */ 149 #ifdef NETGRAPH_DEBUG 150 HK_MAGIC, 151 __FILE__, 152 __LINE__, 153 {NULL} 154 #endif /* NETGRAPH_DEBUG */ 155 }; 156 157 /* 158 * END DEAD STRUCTURES 159 */ 160 /* List nodes with unallocated work */ 161 static TAILQ_HEAD(, ng_node) ng_worklist = TAILQ_HEAD_INITIALIZER(ng_worklist); 162 static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */ 163 164 /* List of installed types */ 165 static LIST_HEAD(, ng_type) ng_typelist; 166 static struct mtx ng_typelist_mtx; 167 168 /* Hash related definitions */ 169 /* XXX Don't need to initialise them because it's a LIST */ 170 #define NG_ID_HASH_SIZE 32 /* most systems wont need even this many */ 171 static LIST_HEAD(, ng_node) ng_ID_hash[NG_ID_HASH_SIZE]; 172 static struct mtx ng_idhash_mtx; 173 /* Method to find a node.. used twice so do it here */ 174 #define NG_IDHASH_FN(ID) ((ID) % (NG_ID_HASH_SIZE)) 175 #define NG_IDHASH_FIND(ID, node) \ 176 do { \ 177 mtx_assert(&ng_idhash_mtx, MA_OWNED); \ 178 LIST_FOREACH(node, &ng_ID_hash[NG_IDHASH_FN(ID)], \ 179 nd_idnodes) { \ 180 if (NG_NODE_IS_VALID(node) \ 181 && (NG_NODE_ID(node) == ID)) { \ 182 break; \ 183 } \ 184 } \ 185 } while (0) 186 187 188 /* Internal functions */ 189 static int ng_add_hook(node_p node, const char *name, hook_p * hookp); 190 static int ng_generic_msg(node_p here, item_p item, hook_p lasthook); 191 static ng_ID_t ng_decodeidname(const char *name); 192 static int ngb_mod_event(module_t mod, int event, void *data); 193 static void ng_worklist_remove(node_p node); 194 static void ngintr(void); 195 static int ng_apply_item(node_p node, item_p item, int rw); 196 static void ng_flush_input_queue(struct ng_queue * ngq); 197 static void ng_setisr(node_p node); 198 static node_p ng_ID2noderef(ng_ID_t ID); 199 static int ng_con_nodes(node_p node, const char *name, node_p node2, 200 const char *name2); 201 static void ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2); 202 static void ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2); 203 static int ng_mkpeer(node_p node, const char *name, 204 const char *name2, char *type); 205 206 /* Imported, these used to be externally visible, some may go back. */ 207 void ng_destroy_hook(hook_p hook); 208 node_p ng_name2noderef(node_p node, const char *name); 209 int ng_path2noderef(node_p here, const char *path, 210 node_p *dest, hook_p *lasthook); 211 int ng_make_node(const char *type, node_p *nodepp); 212 int ng_path_parse(char *addr, char **node, char **path, char **hook); 213 void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3); 214 void ng_unname(node_p node); 215 216 217 /* Our own netgraph malloc type */ 218 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages"); 219 MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures"); 220 MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures"); 221 MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", "netgraph item structures"); 222 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage"); 223 224 /* Should not be visible outside this file */ 225 226 #define _NG_ALLOC_HOOK(hook) \ 227 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO) 228 #define _NG_ALLOC_NODE(node) \ 229 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO) 230 231 #define NG_QUEUE_LOCK_INIT(n) \ 232 mtx_init(&(n)->q_mtx, "ng_node", NULL, MTX_DEF) 233 #define NG_QUEUE_LOCK(n) \ 234 mtx_lock(&(n)->q_mtx) 235 #define NG_QUEUE_UNLOCK(n) \ 236 mtx_unlock(&(n)->q_mtx) 237 #define NG_WORKLIST_LOCK_INIT() \ 238 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_DEF) 239 #define NG_WORKLIST_LOCK() \ 240 mtx_lock(&ng_worklist_mtx) 241 #define NG_WORKLIST_UNLOCK() \ 242 mtx_unlock(&ng_worklist_mtx) 243 244 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/ 245 /* 246 * In debug mode: 247 * In an attempt to help track reference count screwups 248 * we do not free objects back to the malloc system, but keep them 249 * in a local cache where we can examine them and keep information safely 250 * after they have been freed. 251 * We use this scheme for nodes and hooks, and to some extent for items. 252 */ 253 static __inline hook_p 254 ng_alloc_hook(void) 255 { 256 hook_p hook; 257 SLIST_ENTRY(ng_hook) temp; 258 mtx_lock(&ng_nodelist_mtx); 259 hook = LIST_FIRST(&ng_freehooks); 260 if (hook) { 261 LIST_REMOVE(hook, hk_hooks); 262 bcopy(&hook->hk_all, &temp, sizeof(temp)); 263 bzero(hook, sizeof(struct ng_hook)); 264 bcopy(&temp, &hook->hk_all, sizeof(temp)); 265 mtx_unlock(&ng_nodelist_mtx); 266 hook->hk_magic = HK_MAGIC; 267 } else { 268 mtx_unlock(&ng_nodelist_mtx); 269 _NG_ALLOC_HOOK(hook); 270 if (hook) { 271 hook->hk_magic = HK_MAGIC; 272 mtx_lock(&ng_nodelist_mtx); 273 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all); 274 mtx_unlock(&ng_nodelist_mtx); 275 } 276 } 277 return (hook); 278 } 279 280 static __inline node_p 281 ng_alloc_node(void) 282 { 283 node_p node; 284 SLIST_ENTRY(ng_node) temp; 285 mtx_lock(&ng_nodelist_mtx); 286 node = LIST_FIRST(&ng_freenodes); 287 if (node) { 288 LIST_REMOVE(node, nd_nodes); 289 bcopy(&node->nd_all, &temp, sizeof(temp)); 290 bzero(node, sizeof(struct ng_node)); 291 bcopy(&temp, &node->nd_all, sizeof(temp)); 292 mtx_unlock(&ng_nodelist_mtx); 293 node->nd_magic = ND_MAGIC; 294 } else { 295 mtx_unlock(&ng_nodelist_mtx); 296 _NG_ALLOC_NODE(node); 297 if (node) { 298 node->nd_magic = ND_MAGIC; 299 mtx_lock(&ng_nodelist_mtx); 300 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all); 301 mtx_unlock(&ng_nodelist_mtx); 302 } 303 } 304 return (node); 305 } 306 307 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0) 308 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0) 309 310 311 #define NG_FREE_HOOK(hook) \ 312 do { \ 313 mtx_lock(&ng_nodelist_mtx); \ 314 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \ 315 hook->hk_magic = 0; \ 316 mtx_unlock(&ng_nodelist_mtx); \ 317 } while (0) 318 319 #define NG_FREE_NODE(node) \ 320 do { \ 321 mtx_lock(&ng_nodelist_mtx); \ 322 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \ 323 node->nd_magic = 0; \ 324 mtx_unlock(&ng_nodelist_mtx); \ 325 } while (0) 326 327 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 328 329 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook) 330 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node) 331 332 #define NG_FREE_HOOK(hook) do { FREE((hook), M_NETGRAPH_HOOK); } while (0) 333 #define NG_FREE_NODE(node) do { FREE((node), M_NETGRAPH_NODE); } while (0) 334 335 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 336 337 /* Set this to kdb_enter("X") to catch all errors as they occur */ 338 #ifndef TRAP_ERROR 339 #define TRAP_ERROR() 340 #endif 341 342 static ng_ID_t nextID = 1; 343 344 #ifdef INVARIANTS 345 #define CHECK_DATA_MBUF(m) do { \ 346 struct mbuf *n; \ 347 int total; \ 348 \ 349 M_ASSERTPKTHDR(m); \ 350 for (total = 0, n = (m); n != NULL; n = n->m_next) { \ 351 total += n->m_len; \ 352 if (n->m_nextpkt != NULL) \ 353 panic("%s: m_nextpkt", __func__); \ 354 } \ 355 \ 356 if ((m)->m_pkthdr.len != total) { \ 357 panic("%s: %d != %d", \ 358 __func__, (m)->m_pkthdr.len, total); \ 359 } \ 360 } while (0) 361 #else 362 #define CHECK_DATA_MBUF(m) 363 #endif 364 365 366 /************************************************************************ 367 Parse type definitions for generic messages 368 ************************************************************************/ 369 370 /* Handy structure parse type defining macro */ 371 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \ 372 static const struct ng_parse_struct_field \ 373 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \ 374 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \ 375 &ng_parse_struct_type, \ 376 &ng_ ## lo ## _type_fields \ 377 } 378 379 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ()); 380 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ()); 381 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ()); 382 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ()); 383 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ()); 384 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ()); 385 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type)); 386 387 /* Get length of an array when the length is stored as a 32 bit 388 value immediately preceding the array -- as with struct namelist 389 and struct typelist. */ 390 static int 391 ng_generic_list_getLength(const struct ng_parse_type *type, 392 const u_char *start, const u_char *buf) 393 { 394 return *((const u_int32_t *)(buf - 4)); 395 } 396 397 /* Get length of the array of struct linkinfo inside a struct hooklist */ 398 static int 399 ng_generic_linkinfo_getLength(const struct ng_parse_type *type, 400 const u_char *start, const u_char *buf) 401 { 402 const struct hooklist *hl = (const struct hooklist *)start; 403 404 return hl->nodeinfo.hooks; 405 } 406 407 /* Array type for a variable length array of struct namelist */ 408 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = { 409 &ng_generic_nodeinfo_type, 410 &ng_generic_list_getLength 411 }; 412 static const struct ng_parse_type ng_generic_nodeinfoarray_type = { 413 &ng_parse_array_type, 414 &ng_nodeinfoarray_type_info 415 }; 416 417 /* Array type for a variable length array of struct typelist */ 418 static const struct ng_parse_array_info ng_typeinfoarray_type_info = { 419 &ng_generic_typeinfo_type, 420 &ng_generic_list_getLength 421 }; 422 static const struct ng_parse_type ng_generic_typeinfoarray_type = { 423 &ng_parse_array_type, 424 &ng_typeinfoarray_type_info 425 }; 426 427 /* Array type for array of struct linkinfo in struct hooklist */ 428 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = { 429 &ng_generic_linkinfo_type, 430 &ng_generic_linkinfo_getLength 431 }; 432 static const struct ng_parse_type ng_generic_linkinfo_array_type = { 433 &ng_parse_array_type, 434 &ng_generic_linkinfo_array_type_info 435 }; 436 437 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type)); 438 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST, 439 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type)); 440 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES, 441 (&ng_generic_nodeinfoarray_type)); 442 443 /* List of commands and how to convert arguments to/from ASCII */ 444 static const struct ng_cmdlist ng_generic_cmds[] = { 445 { 446 NGM_GENERIC_COOKIE, 447 NGM_SHUTDOWN, 448 "shutdown", 449 NULL, 450 NULL 451 }, 452 { 453 NGM_GENERIC_COOKIE, 454 NGM_MKPEER, 455 "mkpeer", 456 &ng_generic_mkpeer_type, 457 NULL 458 }, 459 { 460 NGM_GENERIC_COOKIE, 461 NGM_CONNECT, 462 "connect", 463 &ng_generic_connect_type, 464 NULL 465 }, 466 { 467 NGM_GENERIC_COOKIE, 468 NGM_NAME, 469 "name", 470 &ng_generic_name_type, 471 NULL 472 }, 473 { 474 NGM_GENERIC_COOKIE, 475 NGM_RMHOOK, 476 "rmhook", 477 &ng_generic_rmhook_type, 478 NULL 479 }, 480 { 481 NGM_GENERIC_COOKIE, 482 NGM_NODEINFO, 483 "nodeinfo", 484 NULL, 485 &ng_generic_nodeinfo_type 486 }, 487 { 488 NGM_GENERIC_COOKIE, 489 NGM_LISTHOOKS, 490 "listhooks", 491 NULL, 492 &ng_generic_hooklist_type 493 }, 494 { 495 NGM_GENERIC_COOKIE, 496 NGM_LISTNAMES, 497 "listnames", 498 NULL, 499 &ng_generic_listnodes_type /* same as NGM_LISTNODES */ 500 }, 501 { 502 NGM_GENERIC_COOKIE, 503 NGM_LISTNODES, 504 "listnodes", 505 NULL, 506 &ng_generic_listnodes_type 507 }, 508 { 509 NGM_GENERIC_COOKIE, 510 NGM_LISTTYPES, 511 "listtypes", 512 NULL, 513 &ng_generic_typeinfo_type 514 }, 515 { 516 NGM_GENERIC_COOKIE, 517 NGM_TEXT_CONFIG, 518 "textconfig", 519 NULL, 520 &ng_parse_string_type 521 }, 522 { 523 NGM_GENERIC_COOKIE, 524 NGM_TEXT_STATUS, 525 "textstatus", 526 NULL, 527 &ng_parse_string_type 528 }, 529 { 530 NGM_GENERIC_COOKIE, 531 NGM_ASCII2BINARY, 532 "ascii2binary", 533 &ng_parse_ng_mesg_type, 534 &ng_parse_ng_mesg_type 535 }, 536 { 537 NGM_GENERIC_COOKIE, 538 NGM_BINARY2ASCII, 539 "binary2ascii", 540 &ng_parse_ng_mesg_type, 541 &ng_parse_ng_mesg_type 542 }, 543 { 0 } 544 }; 545 546 /************************************************************************ 547 Node routines 548 ************************************************************************/ 549 550 /* 551 * Instantiate a node of the requested type 552 */ 553 int 554 ng_make_node(const char *typename, node_p *nodepp) 555 { 556 struct ng_type *type; 557 int error; 558 559 /* Check that the type makes sense */ 560 if (typename == NULL) { 561 TRAP_ERROR(); 562 return (EINVAL); 563 } 564 565 /* Locate the node type. If we fail we return. Do not try to load 566 * module. 567 */ 568 if ((type = ng_findtype(typename)) == NULL) 569 return (ENXIO); 570 571 /* 572 * If we have a constructor, then make the node and 573 * call the constructor to do type specific initialisation. 574 */ 575 if (type->constructor != NULL) { 576 if ((error = ng_make_node_common(type, nodepp)) == 0) { 577 if ((error = ((*type->constructor)(*nodepp)) != 0)) { 578 NG_NODE_UNREF(*nodepp); 579 } 580 } 581 } else { 582 /* 583 * Node has no constructor. We cannot ask for one 584 * to be made. It must be brought into existence by 585 * some external agency. The external agency should 586 * call ng_make_node_common() directly to get the 587 * netgraph part initialised. 588 */ 589 TRAP_ERROR(); 590 error = EINVAL; 591 } 592 return (error); 593 } 594 595 /* 596 * Generic node creation. Called by node initialisation for externally 597 * instantiated nodes (e.g. hardware, sockets, etc ). 598 * The returned node has a reference count of 1. 599 */ 600 int 601 ng_make_node_common(struct ng_type *type, node_p *nodepp) 602 { 603 node_p node; 604 605 /* Require the node type to have been already installed */ 606 if (ng_findtype(type->name) == NULL) { 607 TRAP_ERROR(); 608 return (EINVAL); 609 } 610 611 /* Make a node and try attach it to the type */ 612 NG_ALLOC_NODE(node); 613 if (node == NULL) { 614 TRAP_ERROR(); 615 return (ENOMEM); 616 } 617 node->nd_type = type; 618 NG_NODE_REF(node); /* note reference */ 619 type->refs++; 620 621 NG_QUEUE_LOCK_INIT(&node->nd_input_queue); 622 node->nd_input_queue.queue = NULL; 623 node->nd_input_queue.last = &node->nd_input_queue.queue; 624 node->nd_input_queue.q_flags = 0; 625 node->nd_input_queue.q_node = node; 626 627 /* Initialize hook list for new node */ 628 LIST_INIT(&node->nd_hooks); 629 630 /* Link us into the node linked list */ 631 mtx_lock(&ng_nodelist_mtx); 632 LIST_INSERT_HEAD(&ng_nodelist, node, nd_nodes); 633 mtx_unlock(&ng_nodelist_mtx); 634 635 636 /* get an ID and put us in the hash chain */ 637 mtx_lock(&ng_idhash_mtx); 638 for (;;) { /* wrap protection, even if silly */ 639 node_p node2 = NULL; 640 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */ 641 642 /* Is there a problem with the new number? */ 643 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */ 644 if ((node->nd_ID != 0) && (node2 == NULL)) { 645 break; 646 } 647 } 648 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)], 649 node, nd_idnodes); 650 mtx_unlock(&ng_idhash_mtx); 651 652 /* Done */ 653 *nodepp = node; 654 return (0); 655 } 656 657 /* 658 * Forceably start the shutdown process on a node. Either call 659 * its shutdown method, or do the default shutdown if there is 660 * no type-specific method. 661 * 662 * We can only be called from a shutdown message, so we know we have 663 * a writer lock, and therefore exclusive access. It also means 664 * that we should not be on the work queue, but we check anyhow. 665 * 666 * Persistent node types must have a type-specific method which 667 * allocates a new node in which case, this one is irretrievably going away, 668 * or cleans up anything it needs, and just makes the node valid again, 669 * in which case we allow the node to survive. 670 * 671 * XXX We need to think of how to tell a persistent node that we 672 * REALLY need to go away because the hardware has gone or we 673 * are rebooting.... etc. 674 */ 675 void 676 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3) 677 { 678 hook_p hook; 679 680 /* Check if it's already shutting down */ 681 if ((node->nd_flags & NGF_CLOSING) != 0) 682 return; 683 684 if (node == &ng_deadnode) { 685 printf ("shutdown called on deadnode\n"); 686 return; 687 } 688 689 /* Add an extra reference so it doesn't go away during this */ 690 NG_NODE_REF(node); 691 692 /* 693 * Mark it invalid so any newcomers know not to try use it 694 * Also add our own mark so we can't recurse 695 * note that NGF_INVALID does not do this as it's also set during 696 * creation 697 */ 698 node->nd_flags |= NGF_INVALID|NGF_CLOSING; 699 700 /* If node has its pre-shutdown method, then call it first*/ 701 if (node->nd_type && node->nd_type->close) 702 (*node->nd_type->close)(node); 703 704 /* Notify all remaining connected nodes to disconnect */ 705 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL) 706 ng_destroy_hook(hook); 707 708 /* 709 * Drain the input queue forceably. 710 * it has no hooks so what's it going to do, bleed on someone? 711 * Theoretically we came here from a queue entry that was added 712 * Just before the queue was closed, so it should be empty anyway. 713 * Also removes us from worklist if needed. 714 */ 715 ng_flush_input_queue(&node->nd_input_queue); 716 717 /* Ask the type if it has anything to do in this case */ 718 if (node->nd_type && node->nd_type->shutdown) { 719 (*node->nd_type->shutdown)(node); 720 if (NG_NODE_IS_VALID(node)) { 721 /* 722 * Well, blow me down if the node code hasn't declared 723 * that it doesn't want to die. 724 * Presumably it is a persistant node. 725 * If we REALLY want it to go away, 726 * e.g. hardware going away, 727 * Our caller should set NGF_REALLY_DIE in nd_flags. 728 */ 729 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING); 730 NG_NODE_UNREF(node); /* Assume they still have theirs */ 731 return; 732 } 733 } else { /* do the default thing */ 734 NG_NODE_UNREF(node); 735 } 736 737 ng_unname(node); /* basically a NOP these days */ 738 739 /* 740 * Remove extra reference, possibly the last 741 * Possible other holders of references may include 742 * timeout callouts, but theoretically the node's supposed to 743 * have cancelled them. Possibly hardware dependencies may 744 * force a driver to 'linger' with a reference. 745 */ 746 NG_NODE_UNREF(node); 747 } 748 749 /* 750 * Remove a reference to the node, possibly the last. 751 * deadnode always acts as it it were the last. 752 */ 753 int 754 ng_unref_node(node_p node) 755 { 756 int v; 757 758 if (node == &ng_deadnode) { 759 return (0); 760 } 761 762 do { 763 v = node->nd_refs - 1; 764 } while (! atomic_cmpset_int(&node->nd_refs, v + 1, v)); 765 766 if (v == 0) { /* we were the last */ 767 768 mtx_lock(&ng_nodelist_mtx); 769 node->nd_type->refs--; /* XXX maybe should get types lock? */ 770 LIST_REMOVE(node, nd_nodes); 771 mtx_unlock(&ng_nodelist_mtx); 772 773 mtx_lock(&ng_idhash_mtx); 774 LIST_REMOVE(node, nd_idnodes); 775 mtx_unlock(&ng_idhash_mtx); 776 777 mtx_destroy(&node->nd_input_queue.q_mtx); 778 NG_FREE_NODE(node); 779 } 780 return (v); 781 } 782 783 /************************************************************************ 784 Node ID handling 785 ************************************************************************/ 786 static node_p 787 ng_ID2noderef(ng_ID_t ID) 788 { 789 node_p node; 790 mtx_lock(&ng_idhash_mtx); 791 NG_IDHASH_FIND(ID, node); 792 if(node) 793 NG_NODE_REF(node); 794 mtx_unlock(&ng_idhash_mtx); 795 return(node); 796 } 797 798 ng_ID_t 799 ng_node2ID(node_p node) 800 { 801 return (node ? NG_NODE_ID(node) : 0); 802 } 803 804 /************************************************************************ 805 Node name handling 806 ************************************************************************/ 807 808 /* 809 * Assign a node a name. Once assigned, the name cannot be changed. 810 */ 811 int 812 ng_name_node(node_p node, const char *name) 813 { 814 int i; 815 node_p node2; 816 817 /* Check the name is valid */ 818 for (i = 0; i < NG_NODESIZ; i++) { 819 if (name[i] == '\0' || name[i] == '.' || name[i] == ':') 820 break; 821 } 822 if (i == 0 || name[i] != '\0') { 823 TRAP_ERROR(); 824 return (EINVAL); 825 } 826 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */ 827 TRAP_ERROR(); 828 return (EINVAL); 829 } 830 831 /* Check the name isn't already being used */ 832 if ((node2 = ng_name2noderef(node, name)) != NULL) { 833 NG_NODE_UNREF(node2); 834 TRAP_ERROR(); 835 return (EADDRINUSE); 836 } 837 838 /* copy it */ 839 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ); 840 841 return (0); 842 } 843 844 /* 845 * Find a node by absolute name. The name should NOT end with ':' 846 * The name "." means "this node" and "[xxx]" means "the node 847 * with ID (ie, at address) xxx". 848 * 849 * Returns the node if found, else NULL. 850 * Eventually should add something faster than a sequential search. 851 * Note it acquires a reference on the node so you can be sure it's still 852 * there. 853 */ 854 node_p 855 ng_name2noderef(node_p here, const char *name) 856 { 857 node_p node; 858 ng_ID_t temp; 859 860 /* "." means "this node" */ 861 if (strcmp(name, ".") == 0) { 862 NG_NODE_REF(here); 863 return(here); 864 } 865 866 /* Check for name-by-ID */ 867 if ((temp = ng_decodeidname(name)) != 0) { 868 return (ng_ID2noderef(temp)); 869 } 870 871 /* Find node by name */ 872 mtx_lock(&ng_nodelist_mtx); 873 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 874 if (NG_NODE_IS_VALID(node) 875 && NG_NODE_HAS_NAME(node) 876 && (strcmp(NG_NODE_NAME(node), name) == 0)) { 877 break; 878 } 879 } 880 if (node) 881 NG_NODE_REF(node); 882 mtx_unlock(&ng_nodelist_mtx); 883 return (node); 884 } 885 886 /* 887 * Decode an ID name, eg. "[f03034de]". Returns 0 if the 888 * string is not valid, otherwise returns the value. 889 */ 890 static ng_ID_t 891 ng_decodeidname(const char *name) 892 { 893 const int len = strlen(name); 894 char *eptr; 895 u_long val; 896 897 /* Check for proper length, brackets, no leading junk */ 898 if ((len < 3) 899 || (name[0] != '[') 900 || (name[len - 1] != ']') 901 || (!isxdigit(name[1]))) { 902 return ((ng_ID_t)0); 903 } 904 905 /* Decode number */ 906 val = strtoul(name + 1, &eptr, 16); 907 if ((eptr - name != len - 1) 908 || (val == ULONG_MAX) 909 || (val == 0)) { 910 return ((ng_ID_t)0); 911 } 912 return (ng_ID_t)val; 913 } 914 915 /* 916 * Remove a name from a node. This should only be called 917 * when shutting down and removing the node. 918 * IF we allow name changing this may be more resurrected. 919 */ 920 void 921 ng_unname(node_p node) 922 { 923 } 924 925 /************************************************************************ 926 Hook routines 927 Names are not optional. Hooks are always connected, except for a 928 brief moment within these routines. On invalidation or during creation 929 they are connected to the 'dead' hook. 930 ************************************************************************/ 931 932 /* 933 * Remove a hook reference 934 */ 935 void 936 ng_unref_hook(hook_p hook) 937 { 938 int v; 939 940 if (hook == &ng_deadhook) { 941 return; 942 } 943 do { 944 v = hook->hk_refs; 945 } while (! atomic_cmpset_int(&hook->hk_refs, v, v - 1)); 946 947 if (v == 1) { /* we were the last */ 948 if (_NG_HOOK_NODE(hook)) { /* it'll probably be ng_deadnode */ 949 _NG_NODE_UNREF((_NG_HOOK_NODE(hook))); 950 hook->hk_node = NULL; 951 } 952 NG_FREE_HOOK(hook); 953 } 954 } 955 956 /* 957 * Add an unconnected hook to a node. Only used internally. 958 * Assumes node is locked. (XXX not yet true ) 959 */ 960 static int 961 ng_add_hook(node_p node, const char *name, hook_p *hookp) 962 { 963 hook_p hook; 964 int error = 0; 965 966 /* Check that the given name is good */ 967 if (name == NULL) { 968 TRAP_ERROR(); 969 return (EINVAL); 970 } 971 if (ng_findhook(node, name) != NULL) { 972 TRAP_ERROR(); 973 return (EEXIST); 974 } 975 976 /* Allocate the hook and link it up */ 977 NG_ALLOC_HOOK(hook); 978 if (hook == NULL) { 979 TRAP_ERROR(); 980 return (ENOMEM); 981 } 982 hook->hk_refs = 1; /* add a reference for us to return */ 983 hook->hk_flags = HK_INVALID; 984 hook->hk_peer = &ng_deadhook; /* start off this way */ 985 hook->hk_node = node; 986 NG_NODE_REF(node); /* each hook counts as a reference */ 987 988 /* Set hook name */ 989 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ); 990 991 /* 992 * Check if the node type code has something to say about it 993 * If it fails, the unref of the hook will also unref the node. 994 */ 995 if (node->nd_type->newhook != NULL) { 996 if ((error = (*node->nd_type->newhook)(node, hook, name))) { 997 NG_HOOK_UNREF(hook); /* this frees the hook */ 998 return (error); 999 } 1000 } 1001 /* 1002 * The 'type' agrees so far, so go ahead and link it in. 1003 * We'll ask again later when we actually connect the hooks. 1004 */ 1005 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1006 node->nd_numhooks++; 1007 NG_HOOK_REF(hook); /* one for the node */ 1008 1009 if (hookp) 1010 *hookp = hook; 1011 return (0); 1012 } 1013 1014 /* 1015 * Find a hook 1016 * 1017 * Node types may supply their own optimized routines for finding 1018 * hooks. If none is supplied, we just do a linear search. 1019 * XXX Possibly we should add a reference to the hook? 1020 */ 1021 hook_p 1022 ng_findhook(node_p node, const char *name) 1023 { 1024 hook_p hook; 1025 1026 if (node->nd_type->findhook != NULL) 1027 return (*node->nd_type->findhook)(node, name); 1028 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) { 1029 if (NG_HOOK_IS_VALID(hook) 1030 && (strcmp(NG_HOOK_NAME(hook), name) == 0)) 1031 return (hook); 1032 } 1033 return (NULL); 1034 } 1035 1036 /* 1037 * Destroy a hook 1038 * 1039 * As hooks are always attached, this really destroys two hooks. 1040 * The one given, and the one attached to it. Disconnect the hooks 1041 * from each other first. We reconnect the peer hook to the 'dead' 1042 * hook so that it can still exist after we depart. We then 1043 * send the peer its own destroy message. This ensures that we only 1044 * interact with the peer's structures when it is locked processing that 1045 * message. We hold a reference to the peer hook so we are guaranteed that 1046 * the peer hook and node are still going to exist until 1047 * we are finished there as the hook holds a ref on the node. 1048 * We run this same code again on the peer hook, but that time it is already 1049 * attached to the 'dead' hook. 1050 * 1051 * This routine is called at all stages of hook creation 1052 * on error detection and must be able to handle any such stage. 1053 */ 1054 void 1055 ng_destroy_hook(hook_p hook) 1056 { 1057 hook_p peer; 1058 node_p node; 1059 1060 if (hook == &ng_deadhook) { /* better safe than sorry */ 1061 printf("ng_destroy_hook called on deadhook\n"); 1062 return; 1063 } 1064 1065 /* 1066 * Protect divorce process with mutex, to avoid races on 1067 * simultaneous disconnect. 1068 */ 1069 mtx_lock(&ng_topo_mtx); 1070 1071 hook->hk_flags |= HK_INVALID; 1072 1073 peer = NG_HOOK_PEER(hook); 1074 node = NG_HOOK_NODE(hook); 1075 1076 if (peer && (peer != &ng_deadhook)) { 1077 /* 1078 * Set the peer to point to ng_deadhook 1079 * from this moment on we are effectively independent it. 1080 * send it an rmhook message of it's own. 1081 */ 1082 peer->hk_peer = &ng_deadhook; /* They no longer know us */ 1083 hook->hk_peer = &ng_deadhook; /* Nor us, them */ 1084 if (NG_HOOK_NODE(peer) == &ng_deadnode) { 1085 /* 1086 * If it's already divorced from a node, 1087 * just free it. 1088 */ 1089 mtx_unlock(&ng_topo_mtx); 1090 } else { 1091 mtx_unlock(&ng_topo_mtx); 1092 ng_rmhook_self(peer); /* Send it a surprise */ 1093 } 1094 NG_HOOK_UNREF(peer); /* account for peer link */ 1095 NG_HOOK_UNREF(hook); /* account for peer link */ 1096 } else 1097 mtx_unlock(&ng_topo_mtx); 1098 1099 mtx_assert(&ng_topo_mtx, MA_NOTOWNED); 1100 1101 /* 1102 * Remove the hook from the node's list to avoid possible recursion 1103 * in case the disconnection results in node shutdown. 1104 */ 1105 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */ 1106 return; 1107 } 1108 LIST_REMOVE(hook, hk_hooks); 1109 node->nd_numhooks--; 1110 if (node->nd_type->disconnect) { 1111 /* 1112 * The type handler may elect to destroy the node so don't 1113 * trust its existence after this point. (except 1114 * that we still hold a reference on it. (which we 1115 * inherrited from the hook we are destroying) 1116 */ 1117 (*node->nd_type->disconnect) (hook); 1118 } 1119 1120 /* 1121 * Note that because we will point to ng_deadnode, the original node 1122 * is not decremented automatically so we do that manually. 1123 */ 1124 _NG_HOOK_NODE(hook) = &ng_deadnode; 1125 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */ 1126 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */ 1127 } 1128 1129 /* 1130 * Take two hooks on a node and merge the connection so that the given node 1131 * is effectively bypassed. 1132 */ 1133 int 1134 ng_bypass(hook_p hook1, hook_p hook2) 1135 { 1136 if (hook1->hk_node != hook2->hk_node) { 1137 TRAP_ERROR(); 1138 return (EINVAL); 1139 } 1140 hook1->hk_peer->hk_peer = hook2->hk_peer; 1141 hook2->hk_peer->hk_peer = hook1->hk_peer; 1142 1143 hook1->hk_peer = &ng_deadhook; 1144 hook2->hk_peer = &ng_deadhook; 1145 1146 NG_HOOK_UNREF(hook1); 1147 NG_HOOK_UNREF(hook2); 1148 1149 /* XXX If we ever cache methods on hooks update them as well */ 1150 ng_destroy_hook(hook1); 1151 ng_destroy_hook(hook2); 1152 return (0); 1153 } 1154 1155 /* 1156 * Install a new netgraph type 1157 */ 1158 int 1159 ng_newtype(struct ng_type *tp) 1160 { 1161 const size_t namelen = strlen(tp->name); 1162 1163 /* Check version and type name fields */ 1164 if ((tp->version != NG_ABI_VERSION) 1165 || (namelen == 0) 1166 || (namelen >= NG_TYPESIZ)) { 1167 TRAP_ERROR(); 1168 if (tp->version != NG_ABI_VERSION) { 1169 printf("Netgraph: Node type rejected. ABI mismatch. Suggest recompile\n"); 1170 } 1171 return (EINVAL); 1172 } 1173 1174 /* Check for name collision */ 1175 if (ng_findtype(tp->name) != NULL) { 1176 TRAP_ERROR(); 1177 return (EEXIST); 1178 } 1179 1180 1181 /* Link in new type */ 1182 mtx_lock(&ng_typelist_mtx); 1183 LIST_INSERT_HEAD(&ng_typelist, tp, types); 1184 tp->refs = 1; /* first ref is linked list */ 1185 mtx_unlock(&ng_typelist_mtx); 1186 return (0); 1187 } 1188 1189 /* 1190 * unlink a netgraph type 1191 * If no examples exist 1192 */ 1193 int 1194 ng_rmtype(struct ng_type *tp) 1195 { 1196 /* Check for name collision */ 1197 if (tp->refs != 1) { 1198 TRAP_ERROR(); 1199 return (EBUSY); 1200 } 1201 1202 /* Unlink type */ 1203 mtx_lock(&ng_typelist_mtx); 1204 LIST_REMOVE(tp, types); 1205 mtx_unlock(&ng_typelist_mtx); 1206 return (0); 1207 } 1208 1209 /* 1210 * Look for a type of the name given 1211 */ 1212 struct ng_type * 1213 ng_findtype(const char *typename) 1214 { 1215 struct ng_type *type; 1216 1217 mtx_lock(&ng_typelist_mtx); 1218 LIST_FOREACH(type, &ng_typelist, types) { 1219 if (strcmp(type->name, typename) == 0) 1220 break; 1221 } 1222 mtx_unlock(&ng_typelist_mtx); 1223 return (type); 1224 } 1225 1226 /************************************************************************ 1227 Composite routines 1228 ************************************************************************/ 1229 /* 1230 * Connect two nodes using the specified hooks, using queued functions. 1231 */ 1232 static void 1233 ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2) 1234 { 1235 1236 /* 1237 * When we run, we know that the node 'node' is locked for us. 1238 * Our caller has a reference on the hook. 1239 * Our caller has a reference on the node. 1240 * (In this case our caller is ng_apply_item() ). 1241 * The peer hook has a reference on the hook. 1242 * We are all set up except for the final call to the node, and 1243 * the clearing of the INVALID flag. 1244 */ 1245 if (NG_HOOK_NODE(hook) == &ng_deadnode) { 1246 /* 1247 * The node must have been freed again since we last visited 1248 * here. ng_destry_hook() has this effect but nothing else does. 1249 * We should just release our references and 1250 * free anything we can think of. 1251 * Since we know it's been destroyed, and it's our caller 1252 * that holds the references, just return. 1253 */ 1254 return ; 1255 } 1256 if (hook->hk_node->nd_type->connect) { 1257 if ((*hook->hk_node->nd_type->connect) (hook)) { 1258 ng_destroy_hook(hook); /* also zaps peer */ 1259 printf("failed in ng_con_part3()\n"); 1260 return ; 1261 } 1262 } 1263 /* 1264 * XXX this is wrong for SMP. Possibly we need 1265 * to separate out 'create' and 'invalid' flags. 1266 * should only set flags on hooks we have locked under our node. 1267 */ 1268 hook->hk_flags &= ~HK_INVALID; 1269 return ; 1270 } 1271 1272 static void 1273 ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2) 1274 { 1275 hook_p peer; 1276 1277 /* 1278 * When we run, we know that the node 'node' is locked for us. 1279 * Our caller has a reference on the hook. 1280 * Our caller has a reference on the node. 1281 * (In this case our caller is ng_apply_item() ). 1282 * The peer hook has a reference on the hook. 1283 * our node pointer points to the 'dead' node. 1284 * First check the hook name is unique. 1285 * Should not happen because we checked before queueing this. 1286 */ 1287 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) { 1288 TRAP_ERROR(); 1289 ng_destroy_hook(hook); /* should destroy peer too */ 1290 printf("failed in ng_con_part2()\n"); 1291 return ; 1292 } 1293 /* 1294 * Check if the node type code has something to say about it 1295 * If it fails, the unref of the hook will also unref the attached node, 1296 * however since that node is 'ng_deadnode' this will do nothing. 1297 * The peer hook will also be destroyed. 1298 */ 1299 if (node->nd_type->newhook != NULL) { 1300 if ((*node->nd_type->newhook)(node, hook, hook->hk_name)) { 1301 ng_destroy_hook(hook); /* should destroy peer too */ 1302 printf("failed in ng_con_part2()\n"); 1303 return ; 1304 } 1305 } 1306 1307 /* 1308 * The 'type' agrees so far, so go ahead and link it in. 1309 * We'll ask again later when we actually connect the hooks. 1310 */ 1311 hook->hk_node = node; /* just overwrite ng_deadnode */ 1312 NG_NODE_REF(node); /* each hook counts as a reference */ 1313 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1314 node->nd_numhooks++; 1315 NG_HOOK_REF(hook); /* one for the node */ 1316 1317 /* 1318 * We now have a symmetrical situation, where both hooks have been 1319 * linked to their nodes, the newhook methods have been called 1320 * And the references are all correct. The hooks are still marked 1321 * as invalid, as we have not called the 'connect' methods 1322 * yet. 1323 * We can call the local one immediately as we have the 1324 * node locked, but we need to queue the remote one. 1325 */ 1326 if (hook->hk_node->nd_type->connect) { 1327 if ((*hook->hk_node->nd_type->connect) (hook)) { 1328 ng_destroy_hook(hook); /* also zaps peer */ 1329 printf("failed in ng_con_part2(A)\n"); 1330 return ; 1331 } 1332 } 1333 1334 /* 1335 * Acquire topo mutex to avoid race with ng_destroy_hook(). 1336 */ 1337 mtx_lock(&ng_topo_mtx); 1338 peer = hook->hk_peer; 1339 if (peer == &ng_deadhook) { 1340 mtx_unlock(&ng_topo_mtx); 1341 printf("failed in ng_con_part2(B)\n"); 1342 ng_destroy_hook(hook); 1343 return ; 1344 } 1345 mtx_unlock(&ng_topo_mtx); 1346 1347 if (ng_send_fn(peer->hk_node, peer, &ng_con_part3, arg1, arg2)) { 1348 printf("failed in ng_con_part2(C)\n"); 1349 ng_destroy_hook(hook); /* also zaps peer */ 1350 return ; 1351 } 1352 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */ 1353 return ; 1354 } 1355 1356 /* 1357 * Connect this node with another node. We assume that this node is 1358 * currently locked, as we are only called from an NGM_CONNECT message. 1359 */ 1360 static int 1361 ng_con_nodes(node_p node, const char *name, node_p node2, const char *name2) 1362 { 1363 int error; 1364 hook_p hook; 1365 hook_p hook2; 1366 1367 if (ng_findhook(node2, name2) != NULL) { 1368 return(EEXIST); 1369 } 1370 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */ 1371 return (error); 1372 /* Allocate the other hook and link it up */ 1373 NG_ALLOC_HOOK(hook2); 1374 if (hook2 == NULL) { 1375 TRAP_ERROR(); 1376 ng_destroy_hook(hook); /* XXX check ref counts so far */ 1377 NG_HOOK_UNREF(hook); /* including our ref */ 1378 return (ENOMEM); 1379 } 1380 hook2->hk_refs = 1; /* start with a reference for us. */ 1381 hook2->hk_flags = HK_INVALID; 1382 hook2->hk_peer = hook; /* Link the two together */ 1383 hook->hk_peer = hook2; 1384 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/ 1385 NG_HOOK_REF(hook2); 1386 hook2->hk_node = &ng_deadnode; 1387 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ); 1388 1389 /* 1390 * Queue the function above. 1391 * Procesing continues in that function in the lock context of 1392 * the other node. 1393 */ 1394 if ((error = ng_send_fn(node2, hook2, &ng_con_part2, NULL, 0))) { 1395 printf("failed in ng_con_nodes(): %d\n", error); 1396 ng_destroy_hook(hook); /* also zaps peer */ 1397 } 1398 1399 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */ 1400 NG_HOOK_UNREF(hook2); 1401 return (error); 1402 } 1403 1404 /* 1405 * Make a peer and connect. 1406 * We assume that the local node is locked. 1407 * The new node probably doesn't need a lock until 1408 * it has a hook, because it cannot really have any work until then, 1409 * but we should think about it a bit more. 1410 * 1411 * The problem may come if the other node also fires up 1412 * some hardware or a timer or some other source of activation, 1413 * also it may already get a command msg via it's ID. 1414 * 1415 * We could use the same method as ng_con_nodes() but we'd have 1416 * to add ability to remove the node when failing. (Not hard, just 1417 * make arg1 point to the node to remove). 1418 * Unless of course we just ignore failure to connect and leave 1419 * an unconnected node? 1420 */ 1421 static int 1422 ng_mkpeer(node_p node, const char *name, const char *name2, char *type) 1423 { 1424 node_p node2; 1425 hook_p hook1, hook2; 1426 int error; 1427 1428 if ((error = ng_make_node(type, &node2))) { 1429 return (error); 1430 } 1431 1432 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */ 1433 ng_rmnode(node2, NULL, NULL, 0); 1434 return (error); 1435 } 1436 1437 if ((error = ng_add_hook(node2, name2, &hook2))) { 1438 ng_rmnode(node2, NULL, NULL, 0); 1439 ng_destroy_hook(hook1); 1440 NG_HOOK_UNREF(hook1); 1441 return (error); 1442 } 1443 1444 /* 1445 * Actually link the two hooks together. 1446 */ 1447 hook1->hk_peer = hook2; 1448 hook2->hk_peer = hook1; 1449 1450 /* Each hook is referenced by the other */ 1451 NG_HOOK_REF(hook1); 1452 NG_HOOK_REF(hook2); 1453 1454 /* Give each node the opportunity to veto the pending connection */ 1455 if (hook1->hk_node->nd_type->connect) { 1456 error = (*hook1->hk_node->nd_type->connect) (hook1); 1457 } 1458 1459 if ((error == 0) && hook2->hk_node->nd_type->connect) { 1460 error = (*hook2->hk_node->nd_type->connect) (hook2); 1461 1462 } 1463 1464 /* 1465 * drop the references we were holding on the two hooks. 1466 */ 1467 if (error) { 1468 ng_destroy_hook(hook2); /* also zaps hook1 */ 1469 ng_rmnode(node2, NULL, NULL, 0); 1470 } else { 1471 /* As a last act, allow the hooks to be used */ 1472 hook1->hk_flags &= ~HK_INVALID; 1473 hook2->hk_flags &= ~HK_INVALID; 1474 } 1475 NG_HOOK_UNREF(hook1); 1476 NG_HOOK_UNREF(hook2); 1477 return (error); 1478 } 1479 1480 /************************************************************************ 1481 Utility routines to send self messages 1482 ************************************************************************/ 1483 1484 /* Shut this node down as soon as everyone is clear of it */ 1485 /* Should add arg "immediately" to jump the queue */ 1486 int 1487 ng_rmnode_self(node_p node) 1488 { 1489 int error; 1490 1491 if (node == &ng_deadnode) 1492 return (0); 1493 node->nd_flags |= NGF_INVALID; 1494 if (node->nd_flags & NGF_CLOSING) 1495 return (0); 1496 1497 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0); 1498 return (error); 1499 } 1500 1501 static void 1502 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2) 1503 { 1504 ng_destroy_hook(hook); 1505 return ; 1506 } 1507 1508 int 1509 ng_rmhook_self(hook_p hook) 1510 { 1511 int error; 1512 node_p node = NG_HOOK_NODE(hook); 1513 1514 if (node == &ng_deadnode) 1515 return (0); 1516 1517 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0); 1518 return (error); 1519 } 1520 1521 /*********************************************************************** 1522 * Parse and verify a string of the form: <NODE:><PATH> 1523 * 1524 * Such a string can refer to a specific node or a specific hook 1525 * on a specific node, depending on how you look at it. In the 1526 * latter case, the PATH component must not end in a dot. 1527 * 1528 * Both <NODE:> and <PATH> are optional. The <PATH> is a string 1529 * of hook names separated by dots. This breaks out the original 1530 * string, setting *nodep to "NODE" (or NULL if none) and *pathp 1531 * to "PATH" (or NULL if degenerate). Also, *hookp will point to 1532 * the final hook component of <PATH>, if any, otherwise NULL. 1533 * 1534 * This returns -1 if the path is malformed. The char ** are optional. 1535 ***********************************************************************/ 1536 int 1537 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp) 1538 { 1539 char *node, *path, *hook; 1540 int k; 1541 1542 /* 1543 * Extract absolute NODE, if any 1544 */ 1545 for (path = addr; *path && *path != ':'; path++); 1546 if (*path) { 1547 node = addr; /* Here's the NODE */ 1548 *path++ = '\0'; /* Here's the PATH */ 1549 1550 /* Node name must not be empty */ 1551 if (!*node) 1552 return -1; 1553 1554 /* A name of "." is OK; otherwise '.' not allowed */ 1555 if (strcmp(node, ".") != 0) { 1556 for (k = 0; node[k]; k++) 1557 if (node[k] == '.') 1558 return -1; 1559 } 1560 } else { 1561 node = NULL; /* No absolute NODE */ 1562 path = addr; /* Here's the PATH */ 1563 } 1564 1565 /* Snoop for illegal characters in PATH */ 1566 for (k = 0; path[k]; k++) 1567 if (path[k] == ':') 1568 return -1; 1569 1570 /* Check for no repeated dots in PATH */ 1571 for (k = 0; path[k]; k++) 1572 if (path[k] == '.' && path[k + 1] == '.') 1573 return -1; 1574 1575 /* Remove extra (degenerate) dots from beginning or end of PATH */ 1576 if (path[0] == '.') 1577 path++; 1578 if (*path && path[strlen(path) - 1] == '.') 1579 path[strlen(path) - 1] = 0; 1580 1581 /* If PATH has a dot, then we're not talking about a hook */ 1582 if (*path) { 1583 for (hook = path, k = 0; path[k]; k++) 1584 if (path[k] == '.') { 1585 hook = NULL; 1586 break; 1587 } 1588 } else 1589 path = hook = NULL; 1590 1591 /* Done */ 1592 if (nodep) 1593 *nodep = node; 1594 if (pathp) 1595 *pathp = path; 1596 if (hookp) 1597 *hookp = hook; 1598 return (0); 1599 } 1600 1601 /* 1602 * Given a path, which may be absolute or relative, and a starting node, 1603 * return the destination node. 1604 */ 1605 int 1606 ng_path2noderef(node_p here, const char *address, 1607 node_p *destp, hook_p *lasthook) 1608 { 1609 char fullpath[NG_PATHSIZ]; 1610 char *nodename, *path, pbuf[2]; 1611 node_p node, oldnode; 1612 char *cp; 1613 hook_p hook = NULL; 1614 1615 /* Initialize */ 1616 if (destp == NULL) { 1617 TRAP_ERROR(); 1618 return EINVAL; 1619 } 1620 *destp = NULL; 1621 1622 /* Make a writable copy of address for ng_path_parse() */ 1623 strncpy(fullpath, address, sizeof(fullpath) - 1); 1624 fullpath[sizeof(fullpath) - 1] = '\0'; 1625 1626 /* Parse out node and sequence of hooks */ 1627 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) { 1628 TRAP_ERROR(); 1629 return EINVAL; 1630 } 1631 if (path == NULL) { 1632 pbuf[0] = '.'; /* Needs to be writable */ 1633 pbuf[1] = '\0'; 1634 path = pbuf; 1635 } 1636 1637 /* 1638 * For an absolute address, jump to the starting node. 1639 * Note that this holds a reference on the node for us. 1640 * Don't forget to drop the reference if we don't need it. 1641 */ 1642 if (nodename) { 1643 node = ng_name2noderef(here, nodename); 1644 if (node == NULL) { 1645 TRAP_ERROR(); 1646 return (ENOENT); 1647 } 1648 } else { 1649 if (here == NULL) { 1650 TRAP_ERROR(); 1651 return (EINVAL); 1652 } 1653 node = here; 1654 NG_NODE_REF(node); 1655 } 1656 1657 /* 1658 * Now follow the sequence of hooks 1659 * XXX 1660 * We actually cannot guarantee that the sequence 1661 * is not being demolished as we crawl along it 1662 * without extra-ordinary locking etc. 1663 * So this is a bit dodgy to say the least. 1664 * We can probably hold up some things by holding 1665 * the nodelist mutex for the time of this 1666 * crawl if we wanted.. At least that way we wouldn't have to 1667 * worry about the nodes disappearing, but the hooks would still 1668 * be a problem. 1669 */ 1670 for (cp = path; node != NULL && *cp != '\0'; ) { 1671 char *segment; 1672 1673 /* 1674 * Break out the next path segment. Replace the dot we just 1675 * found with a NUL; "cp" points to the next segment (or the 1676 * NUL at the end). 1677 */ 1678 for (segment = cp; *cp != '\0'; cp++) { 1679 if (*cp == '.') { 1680 *cp++ = '\0'; 1681 break; 1682 } 1683 } 1684 1685 /* Empty segment */ 1686 if (*segment == '\0') 1687 continue; 1688 1689 /* We have a segment, so look for a hook by that name */ 1690 hook = ng_findhook(node, segment); 1691 1692 /* Can't get there from here... */ 1693 if (hook == NULL 1694 || NG_HOOK_PEER(hook) == NULL 1695 || NG_HOOK_NOT_VALID(hook) 1696 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) { 1697 TRAP_ERROR(); 1698 NG_NODE_UNREF(node); 1699 #if 0 1700 printf("hooknotvalid %s %s %d %d %d %d ", 1701 path, 1702 segment, 1703 hook == NULL, 1704 NG_HOOK_PEER(hook) == NULL, 1705 NG_HOOK_NOT_VALID(hook), 1706 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))); 1707 #endif 1708 return (ENOENT); 1709 } 1710 1711 /* 1712 * Hop on over to the next node 1713 * XXX 1714 * Big race conditions here as hooks and nodes go away 1715 * *** Idea.. store an ng_ID_t in each hook and use that 1716 * instead of the direct hook in this crawl? 1717 */ 1718 oldnode = node; 1719 if ((node = NG_PEER_NODE(hook))) 1720 NG_NODE_REF(node); /* XXX RACE */ 1721 NG_NODE_UNREF(oldnode); /* XXX another race */ 1722 if (NG_NODE_NOT_VALID(node)) { 1723 NG_NODE_UNREF(node); /* XXX more races */ 1724 node = NULL; 1725 } 1726 } 1727 1728 /* If node somehow missing, fail here (probably this is not needed) */ 1729 if (node == NULL) { 1730 TRAP_ERROR(); 1731 return (ENXIO); 1732 } 1733 1734 /* Done */ 1735 *destp = node; 1736 if (lasthook != NULL) 1737 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL); 1738 return (0); 1739 } 1740 1741 /***************************************************************\ 1742 * Input queue handling. 1743 * All activities are submitted to the node via the input queue 1744 * which implements a multiple-reader/single-writer gate. 1745 * Items which cannot be handled immediately are queued. 1746 * 1747 * read-write queue locking inline functions * 1748 \***************************************************************/ 1749 1750 static __inline item_p ng_dequeue(struct ng_queue * ngq, int *rw); 1751 static __inline item_p ng_acquire_read(struct ng_queue * ngq, 1752 item_p item); 1753 static __inline item_p ng_acquire_write(struct ng_queue * ngq, 1754 item_p item); 1755 static __inline void ng_leave_read(struct ng_queue * ngq); 1756 static __inline void ng_leave_write(struct ng_queue * ngq); 1757 static __inline void ng_queue_rw(struct ng_queue * ngq, 1758 item_p item, int rw); 1759 1760 /* 1761 * Definition of the bits fields in the ng_queue flag word. 1762 * Defined here rather than in netgraph.h because no-one should fiddle 1763 * with them. 1764 * 1765 * The ordering here may be important! don't shuffle these. 1766 */ 1767 /*- 1768 Safety Barrier--------+ (adjustable to suit taste) (not used yet) 1769 | 1770 V 1771 +-------+-------+-------+-------+-------+-------+-------+-------+ 1772 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1773 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |P|A| 1774 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |O|W| 1775 +-------+-------+-------+-------+-------+-------+-------+-------+ 1776 \___________________________ ____________________________/ | | 1777 V | | 1778 [active reader count] | | 1779 | | 1780 Operation Pending -------------------------------+ | 1781 | 1782 Active Writer ---------------------------------------+ 1783 1784 1785 */ 1786 #define WRITER_ACTIVE 0x00000001 1787 #define OP_PENDING 0x00000002 1788 #define READER_INCREMENT 0x00000004 1789 #define READER_MASK 0xfffffffc /* Not valid if WRITER_ACTIVE is set */ 1790 #define SAFETY_BARRIER 0x00100000 /* 128K items queued should be enough */ 1791 1792 /* Defines of more elaborate states on the queue */ 1793 /* Mask of bits a new read cares about */ 1794 #define NGQ_RMASK (WRITER_ACTIVE|OP_PENDING) 1795 1796 /* Mask of bits a new write cares about */ 1797 #define NGQ_WMASK (NGQ_RMASK|READER_MASK) 1798 1799 /* Test to decide if there is something on the queue. */ 1800 #define QUEUE_ACTIVE(QP) ((QP)->q_flags & OP_PENDING) 1801 1802 /* How to decide what the next queued item is. */ 1803 #define HEAD_IS_READER(QP) NGI_QUEUED_READER((QP)->queue) 1804 #define HEAD_IS_WRITER(QP) NGI_QUEUED_WRITER((QP)->queue) /* notused */ 1805 1806 /* Read the status to decide if the next item on the queue can now run. */ 1807 #define QUEUED_READER_CAN_PROCEED(QP) \ 1808 (((QP)->q_flags & (NGQ_RMASK & ~OP_PENDING)) == 0) 1809 #define QUEUED_WRITER_CAN_PROCEED(QP) \ 1810 (((QP)->q_flags & (NGQ_WMASK & ~OP_PENDING)) == 0) 1811 1812 /* Is there a chance of getting ANY work off the queue? */ 1813 #define NEXT_QUEUED_ITEM_CAN_PROCEED(QP) \ 1814 (QUEUE_ACTIVE(QP) && \ 1815 ((HEAD_IS_READER(QP)) ? QUEUED_READER_CAN_PROCEED(QP) : \ 1816 QUEUED_WRITER_CAN_PROCEED(QP))) 1817 1818 1819 #define NGQRW_R 0 1820 #define NGQRW_W 1 1821 1822 /* 1823 * Taking into account the current state of the queue and node, possibly take 1824 * the next entry off the queue and return it. Return NULL if there was 1825 * nothing we could return, either because there really was nothing there, or 1826 * because the node was in a state where it cannot yet process the next item 1827 * on the queue. 1828 * 1829 * This MUST MUST MUST be called with the mutex held. 1830 */ 1831 static __inline item_p 1832 ng_dequeue(struct ng_queue *ngq, int *rw) 1833 { 1834 item_p item; 1835 u_int add_arg; 1836 1837 mtx_assert(&ngq->q_mtx, MA_OWNED); 1838 /* 1839 * If there is nothing queued, then just return. 1840 * No point in continuing. 1841 * XXXGL: assert this? 1842 */ 1843 if (!QUEUE_ACTIVE(ngq)) { 1844 CTR4(KTR_NET, "%20s: node [%x] (%p) queue empty; " 1845 "queue flags 0x%lx", __func__, 1846 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1847 return (NULL); 1848 } 1849 1850 /* 1851 * From here, we can assume there is a head item. 1852 * We need to find out what it is and if it can be dequeued, given 1853 * the current state of the node. 1854 */ 1855 if (HEAD_IS_READER(ngq)) { 1856 if (!QUEUED_READER_CAN_PROCEED(ngq)) { 1857 /* 1858 * It's a reader but we can't use it. 1859 * We are stalled so make sure we don't 1860 * get called again until something changes. 1861 */ 1862 ng_worklist_remove(ngq->q_node); 1863 CTR4(KTR_NET, "%20s: node [%x] (%p) queued reader " 1864 "can't proceed; queue flags 0x%lx", __func__, 1865 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1866 return (NULL); 1867 } 1868 /* 1869 * Head of queue is a reader and we have no write active. 1870 * We don't care how many readers are already active. 1871 * Add the correct increment for the reader count. 1872 */ 1873 add_arg = READER_INCREMENT; 1874 *rw = NGQRW_R; 1875 } else if (QUEUED_WRITER_CAN_PROCEED(ngq)) { 1876 /* 1877 * There is a pending write, no readers and no active writer. 1878 * This means we can go ahead with the pending writer. Note 1879 * the fact that we now have a writer, ready for when we take 1880 * it off the queue. 1881 * 1882 * We don't need to worry about a possible collision with the 1883 * fasttrack reader. 1884 * 1885 * The fasttrack thread may take a long time to discover that we 1886 * are running so we would have an inconsistent state in the 1887 * flags for a while. Since we ignore the reader count 1888 * entirely when the WRITER_ACTIVE flag is set, this should 1889 * not matter (in fact it is defined that way). If it tests 1890 * the flag before this operation, the OP_PENDING flag 1891 * will make it fail, and if it tests it later, the 1892 * WRITER_ACTIVE flag will do the same. If it is SO slow that 1893 * we have actually completed the operation, and neither flag 1894 * is set by the time that it tests the flags, then it is 1895 * actually ok for it to continue. If it completes and we've 1896 * finished and the read pending is set it still fails. 1897 * 1898 * So we can just ignore it, as long as we can ensure that the 1899 * transition from WRITE_PENDING state to the WRITER_ACTIVE 1900 * state is atomic. 1901 * 1902 * After failing, first it will be held back by the mutex, then 1903 * when it can proceed, it will queue its request, then it 1904 * would arrive at this function. Usually it will have to 1905 * leave empty handed because the ACTIVE WRITER bit will be 1906 * set. 1907 * 1908 * Adjust the flags for the new active writer. 1909 */ 1910 add_arg = WRITER_ACTIVE; 1911 *rw = NGQRW_W; 1912 /* 1913 * We want to write "active writer, no readers " Now go make 1914 * it true. In fact there may be a number in the readers 1915 * count but we know it is not true and will be fixed soon. 1916 * We will fix the flags for the next pending entry in a 1917 * moment. 1918 */ 1919 } else { 1920 /* 1921 * We can't dequeue anything.. return and say so. Probably we 1922 * have a write pending and the readers count is non zero. If 1923 * we got here because a reader hit us just at the wrong 1924 * moment with the fasttrack code, and put us in a strange 1925 * state, then it will be coming through in just a moment, 1926 * (just as soon as we release the mutex) and keep things 1927 * moving. 1928 * Make sure we remove ourselves from the work queue. It 1929 * would be a waste of effort to do all this again. 1930 */ 1931 ng_worklist_remove(ngq->q_node); 1932 CTR4(KTR_NET, "%20s: node [%x] (%p) can't dequeue anything; " 1933 "queue flags 0x%lx", __func__, 1934 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1935 return (NULL); 1936 } 1937 1938 /* 1939 * Now we dequeue the request (whatever it may be) and correct the 1940 * pending flags and the next and last pointers. 1941 */ 1942 item = ngq->queue; 1943 ngq->queue = item->el_next; 1944 CTR6(KTR_NET, "%20s: node [%x] (%p) dequeued item %p with flags 0x%lx; " 1945 "queue flags 0x%lx", __func__, 1946 ngq->q_node->nd_ID,ngq->q_node, item, item->el_flags, ngq->q_flags); 1947 if (ngq->last == &(item->el_next)) { 1948 /* 1949 * that was the last entry in the queue so set the 'last 1950 * pointer up correctly and make sure the pending flag is 1951 * clear. 1952 */ 1953 add_arg += -OP_PENDING; 1954 ngq->last = &(ngq->queue); 1955 /* 1956 * Whatever flag was set will be cleared and 1957 * the new acive field will be set by the add as well, 1958 * so we don't need to change add_arg. 1959 * But we know we don't need to be on the work list. 1960 */ 1961 atomic_add_long(&ngq->q_flags, add_arg); 1962 ng_worklist_remove(ngq->q_node); 1963 } else { 1964 /* 1965 * Since there is still something on the queue 1966 * we don't need to change the PENDING flag. 1967 */ 1968 atomic_add_long(&ngq->q_flags, add_arg); 1969 /* 1970 * If we see more doable work, make sure we are 1971 * on the work queue. 1972 */ 1973 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) { 1974 ng_setisr(ngq->q_node); 1975 } 1976 } 1977 CTR6(KTR_NET, "%20s: node [%x] (%p) returning item %p as %s; " 1978 "queue flags 0x%lx", __func__, 1979 ngq->q_node->nd_ID, ngq->q_node, item, *rw ? "WRITER" : "READER" , 1980 ngq->q_flags); 1981 return (item); 1982 } 1983 1984 /* 1985 * Queue a packet to be picked up by someone else. 1986 * We really don't care who, but we can't or don't want to hang around 1987 * to process it ourselves. We are probably an interrupt routine.. 1988 * If the queue could be run, flag the netisr handler to start. 1989 */ 1990 static __inline void 1991 ng_queue_rw(struct ng_queue * ngq, item_p item, int rw) 1992 { 1993 mtx_assert(&ngq->q_mtx, MA_OWNED); 1994 1995 if (rw == NGQRW_W) 1996 NGI_SET_WRITER(item); 1997 else 1998 NGI_SET_READER(item); 1999 item->el_next = NULL; /* maybe not needed */ 2000 *ngq->last = item; 2001 CTR5(KTR_NET, "%20s: node [%x] (%p) queued item %p as %s", __func__, 2002 ngq->q_node->nd_ID, ngq->q_node, item, rw ? "WRITER" : "READER" ); 2003 /* 2004 * If it was the first item in the queue then we need to 2005 * set the last pointer and the type flags. 2006 */ 2007 if (ngq->last == &(ngq->queue)) { 2008 atomic_add_long(&ngq->q_flags, OP_PENDING); 2009 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__, 2010 ngq->q_node->nd_ID, ngq->q_node); 2011 } 2012 2013 ngq->last = &(item->el_next); 2014 /* 2015 * We can take the worklist lock with the node locked 2016 * BUT NOT THE REVERSE! 2017 */ 2018 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2019 ng_setisr(ngq->q_node); 2020 } 2021 2022 2023 /* 2024 * This function 'cheats' in that it first tries to 'grab' the use of the 2025 * node, without going through the mutex. We can do this becasue of the 2026 * semantics of the lock. The semantics include a clause that says that the 2027 * value of the readers count is invalid if the WRITER_ACTIVE flag is set. It 2028 * also says that the WRITER_ACTIVE flag cannot be set if the readers count 2029 * is not zero. Note that this talks about what is valid to SET the 2030 * WRITER_ACTIVE flag, because from the moment it is set, the value if the 2031 * reader count is immaterial, and not valid. The two 'pending' flags have a 2032 * similar effect, in that If they are orthogonal to the two active fields in 2033 * how they are set, but if either is set, the attempted 'grab' need to be 2034 * backed out because there is earlier work, and we maintain ordering in the 2035 * queue. The result of this is that the reader request can try obtain use of 2036 * the node with only a single atomic addition, and without any of the mutex 2037 * overhead. If this fails the operation degenerates to the same as for other 2038 * cases. 2039 * 2040 */ 2041 static __inline item_p 2042 ng_acquire_read(struct ng_queue *ngq, item_p item) 2043 { 2044 KASSERT(ngq != &ng_deadnode.nd_input_queue, 2045 ("%s: working on deadnode", __func__)); 2046 2047 /* ######### Hack alert ######### */ 2048 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 2049 if ((ngq->q_flags & NGQ_RMASK) == 0) { 2050 /* Successfully grabbed node */ 2051 CTR4(KTR_NET, "%20s: node [%x] (%p) fast acquired item %p", 2052 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2053 return (item); 2054 } 2055 /* undo the damage if we didn't succeed */ 2056 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 2057 2058 /* ######### End Hack alert ######### */ 2059 NG_QUEUE_LOCK(ngq); 2060 /* 2061 * Try again. Another processor (or interrupt for that matter) may 2062 * have removed the last queued item that was stopping us from 2063 * running, between the previous test, and the moment that we took 2064 * the mutex. (Or maybe a writer completed.) 2065 * Even if another fast-track reader hits during this period 2066 * we don't care as multiple readers is OK. 2067 */ 2068 if ((ngq->q_flags & NGQ_RMASK) == 0) { 2069 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 2070 NG_QUEUE_UNLOCK(ngq); 2071 CTR4(KTR_NET, "%20s: node [%x] (%p) slow acquired item %p", 2072 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2073 return (item); 2074 } 2075 2076 /* 2077 * and queue the request for later. 2078 */ 2079 ng_queue_rw(ngq, item, NGQRW_R); 2080 NG_QUEUE_UNLOCK(ngq); 2081 2082 return (NULL); 2083 } 2084 2085 static __inline item_p 2086 ng_acquire_write(struct ng_queue *ngq, item_p item) 2087 { 2088 KASSERT(ngq != &ng_deadnode.nd_input_queue, 2089 ("%s: working on deadnode", __func__)); 2090 2091 restart: 2092 NG_QUEUE_LOCK(ngq); 2093 /* 2094 * If there are no readers, no writer, and no pending packets, then 2095 * we can just go ahead. In all other situations we need to queue the 2096 * request 2097 */ 2098 if ((ngq->q_flags & NGQ_WMASK) == 0) { 2099 /* collision could happen *HERE* */ 2100 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE); 2101 NG_QUEUE_UNLOCK(ngq); 2102 if (ngq->q_flags & READER_MASK) { 2103 /* Collision with fast-track reader */ 2104 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2105 goto restart; 2106 } 2107 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p", 2108 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2109 return (item); 2110 } 2111 2112 /* 2113 * and queue the request for later. 2114 */ 2115 ng_queue_rw(ngq, item, NGQRW_W); 2116 NG_QUEUE_UNLOCK(ngq); 2117 2118 return (NULL); 2119 } 2120 2121 #if 0 2122 static __inline item_p 2123 ng_upgrade_write(struct ng_queue *ngq, item_p item) 2124 { 2125 KASSERT(ngq != &ng_deadnode.nd_input_queue, 2126 ("%s: working on deadnode", __func__)); 2127 2128 NGI_SET_WRITER(item); 2129 2130 mtx_lock_spin(&(ngq->q_mtx)); 2131 2132 /* 2133 * There will never be no readers as we are there ourselves. 2134 * Set the WRITER_ACTIVE flags ASAP to block out fast track readers. 2135 * The caller we are running from will call ng_leave_read() 2136 * soon, so we must account for that. We must leave again with the 2137 * READER lock. If we find other readers, then 2138 * queue the request for later. However "later" may be rignt now 2139 * if there are no readers. We don't really care if there are queued 2140 * items as we will bypass them anyhow. 2141 */ 2142 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE - READER_INCREMENT); 2143 if (ngq->q_flags & (NGQ_WMASK & ~OP_PENDING) == WRITER_ACTIVE) { 2144 mtx_unlock_spin(&(ngq->q_mtx)); 2145 2146 /* It's just us, act on the item. */ 2147 /* will NOT drop writer lock when done */ 2148 ng_apply_item(node, item, 0); 2149 2150 /* 2151 * Having acted on the item, atomically 2152 * down grade back to READER and finish up 2153 */ 2154 atomic_add_long(&ngq->q_flags, 2155 READER_INCREMENT - WRITER_ACTIVE); 2156 2157 /* Our caller will call ng_leave_read() */ 2158 return; 2159 } 2160 /* 2161 * It's not just us active, so queue us AT THE HEAD. 2162 * "Why?" I hear you ask. 2163 * Put us at the head of the queue as we've already been 2164 * through it once. If there is nothing else waiting, 2165 * set the correct flags. 2166 */ 2167 if ((item->el_next = ngq->queue) == NULL) { 2168 /* 2169 * Set up the "last" pointer. 2170 * We are the only (and thus last) item 2171 */ 2172 ngq->last = &(item->el_next); 2173 2174 /* We've gone from, 0 to 1 item in the queue */ 2175 atomic_add_long(&ngq->q_flags, OP_PENDING); 2176 2177 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__, 2178 ngq->q_node->nd_ID, ngq->q_node); 2179 }; 2180 ngq->queue = item; 2181 CTR5(KTR_NET, "%20s: node [%x] (%p) requeued item %p as WRITER", 2182 __func__, ngq->q_node->nd_ID, ngq->q_node, item ); 2183 2184 /* Reverse what we did above. That downgrades us back to reader */ 2185 atomic_add_long(&ngq->q_flags, READER_INCREMENT - WRITER_ACTIVE); 2186 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2187 ng_setisr(ngq->q_node); 2188 mtx_unlock_spin(&(ngq->q_mtx)); 2189 2190 return; 2191 } 2192 2193 #endif 2194 2195 static __inline void 2196 ng_leave_read(struct ng_queue *ngq) 2197 { 2198 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 2199 } 2200 2201 static __inline void 2202 ng_leave_write(struct ng_queue *ngq) 2203 { 2204 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2205 } 2206 2207 static void 2208 ng_flush_input_queue(struct ng_queue * ngq) 2209 { 2210 item_p item; 2211 2212 NG_QUEUE_LOCK(ngq); 2213 while (ngq->queue) { 2214 item = ngq->queue; 2215 ngq->queue = item->el_next; 2216 if (ngq->last == &(item->el_next)) { 2217 ngq->last = &(ngq->queue); 2218 atomic_add_long(&ngq->q_flags, -OP_PENDING); 2219 } 2220 NG_QUEUE_UNLOCK(ngq); 2221 2222 /* If the item is supplying a callback, call it with an error */ 2223 if (item->apply != NULL) { 2224 (item->apply)(item->context, ENOENT); 2225 item->apply = NULL; 2226 } 2227 NG_FREE_ITEM(item); 2228 NG_QUEUE_LOCK(ngq); 2229 } 2230 /* 2231 * Take us off the work queue if we are there. 2232 * We definately have no work to be done. 2233 */ 2234 ng_worklist_remove(ngq->q_node); 2235 NG_QUEUE_UNLOCK(ngq); 2236 } 2237 2238 /*********************************************************************** 2239 * Externally visible method for sending or queueing messages or data. 2240 ***********************************************************************/ 2241 2242 /* 2243 * The module code should have filled out the item correctly by this stage: 2244 * Common: 2245 * reference to destination node. 2246 * Reference to destination rcv hook if relevant. 2247 * Data: 2248 * pointer to mbuf 2249 * Control_Message: 2250 * pointer to msg. 2251 * ID of original sender node. (return address) 2252 * Function: 2253 * Function pointer 2254 * void * argument 2255 * integer argument 2256 * 2257 * The nodes have several routines and macros to help with this task: 2258 */ 2259 2260 int 2261 ng_snd_item(item_p item, int flags) 2262 { 2263 hook_p hook = NGI_HOOK(item); 2264 node_p node = NGI_NODE(item); 2265 int queue, rw; 2266 struct ng_queue * ngq = &node->nd_input_queue; 2267 int error = 0; 2268 2269 #ifdef NETGRAPH_DEBUG 2270 _ngi_check(item, __FILE__, __LINE__); 2271 #endif 2272 2273 queue = (flags & NG_QUEUE) ? 1 : 0; 2274 2275 if (item == NULL) { 2276 TRAP_ERROR(); 2277 return (EINVAL); /* failed to get queue element */ 2278 } 2279 if (node == NULL) { 2280 NG_FREE_ITEM(item); 2281 TRAP_ERROR(); 2282 return (EINVAL); /* No address */ 2283 } 2284 switch(item->el_flags & NGQF_TYPE) { 2285 case NGQF_DATA: 2286 /* 2287 * DATA MESSAGE 2288 * Delivered to a node via a non-optional hook. 2289 * Both should be present in the item even though 2290 * the node is derivable from the hook. 2291 * References are held on both by the item. 2292 */ 2293 2294 /* Protect nodes from sending NULL pointers 2295 * to each other 2296 */ 2297 if (NGI_M(item) == NULL) 2298 return (EINVAL); 2299 2300 CHECK_DATA_MBUF(NGI_M(item)); 2301 if (hook == NULL) { 2302 NG_FREE_ITEM(item); 2303 TRAP_ERROR(); 2304 return(EINVAL); 2305 } 2306 if ((NG_HOOK_NOT_VALID(hook)) 2307 || (NG_NODE_NOT_VALID(NG_HOOK_NODE(hook)))) { 2308 NG_FREE_ITEM(item); 2309 return (ENOTCONN); 2310 } 2311 if ((hook->hk_flags & HK_QUEUE)) { 2312 queue = 1; 2313 } 2314 break; 2315 case NGQF_MESG: 2316 /* 2317 * CONTROL MESSAGE 2318 * Delivered to a node. 2319 * Hook is optional. 2320 * References are held by the item on the node and 2321 * the hook if it is present. 2322 */ 2323 if (hook && (hook->hk_flags & HK_QUEUE)) { 2324 queue = 1; 2325 } 2326 break; 2327 case NGQF_FN: 2328 break; 2329 default: 2330 NG_FREE_ITEM(item); 2331 TRAP_ERROR(); 2332 return (EINVAL); 2333 } 2334 switch(item->el_flags & NGQF_RW) { 2335 case NGQF_READER: 2336 rw = NGQRW_R; 2337 break; 2338 case NGQF_WRITER: 2339 rw = NGQRW_W; 2340 break; 2341 default: 2342 panic("%s: invalid item flags %lx", __func__, item->el_flags); 2343 } 2344 2345 /* 2346 * If the node specifies single threading, force writer semantics. 2347 * Similarly, the node may say one hook always produces writers. 2348 * These are overrides. 2349 */ 2350 if ((node->nd_flags & NGF_FORCE_WRITER) 2351 || (hook && (hook->hk_flags & HK_FORCE_WRITER))) 2352 rw = NGQRW_W; 2353 2354 if (queue) { 2355 /* Put it on the queue for that node*/ 2356 #ifdef NETGRAPH_DEBUG 2357 _ngi_check(item, __FILE__, __LINE__); 2358 #endif 2359 NG_QUEUE_LOCK(ngq); 2360 ng_queue_rw(ngq, item, rw); 2361 NG_QUEUE_UNLOCK(ngq); 2362 2363 if (flags & NG_PROGRESS) 2364 return (EINPROGRESS); 2365 else 2366 return (0); 2367 } 2368 2369 /* 2370 * We already decided how we will be queueud or treated. 2371 * Try get the appropriate operating permission. 2372 */ 2373 if (rw == NGQRW_R) 2374 item = ng_acquire_read(ngq, item); 2375 else 2376 item = ng_acquire_write(ngq, item); 2377 2378 2379 if (item == NULL) { 2380 if (flags & NG_PROGRESS) 2381 return (EINPROGRESS); 2382 else 2383 return (0); 2384 } 2385 2386 #ifdef NETGRAPH_DEBUG 2387 _ngi_check(item, __FILE__, __LINE__); 2388 #endif 2389 2390 NGI_GET_NODE(item, node); /* zaps stored node */ 2391 2392 error = ng_apply_item(node, item, rw); /* drops r/w lock when done */ 2393 2394 /* 2395 * If the node goes away when we remove the reference, 2396 * whatever we just did caused it.. whatever we do, DO NOT 2397 * access the node again! 2398 */ 2399 if (NG_NODE_UNREF(node) == 0) { 2400 return (error); 2401 } 2402 2403 NG_QUEUE_LOCK(ngq); 2404 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2405 ng_setisr(ngq->q_node); 2406 NG_QUEUE_UNLOCK(ngq); 2407 2408 return (error); 2409 } 2410 2411 /* 2412 * We have an item that was possibly queued somewhere. 2413 * It should contain all the information needed 2414 * to run it on the appropriate node/hook. 2415 */ 2416 static int 2417 ng_apply_item(node_p node, item_p item, int rw) 2418 { 2419 hook_p hook; 2420 int error = 0; 2421 ng_rcvdata_t *rcvdata; 2422 ng_rcvmsg_t *rcvmsg; 2423 ng_apply_t *apply = NULL; 2424 void *context = NULL; 2425 2426 NGI_GET_HOOK(item, hook); /* clears stored hook */ 2427 #ifdef NETGRAPH_DEBUG 2428 _ngi_check(item, __FILE__, __LINE__); 2429 #endif 2430 2431 /* 2432 * If the item has an "apply" callback, store it. 2433 * Clear item's callback immediately, to avoid an extra call if 2434 * the item is reused by the destination node. 2435 */ 2436 if (item->apply != NULL) { 2437 apply = item->apply; 2438 context = item->context; 2439 item->apply = NULL; 2440 } 2441 2442 switch (item->el_flags & NGQF_TYPE) { 2443 case NGQF_DATA: 2444 /* 2445 * Check things are still ok as when we were queued. 2446 */ 2447 if ((hook == NULL) 2448 || NG_HOOK_NOT_VALID(hook) 2449 || NG_NODE_NOT_VALID(node) ) { 2450 error = EIO; 2451 NG_FREE_ITEM(item); 2452 break; 2453 } 2454 /* 2455 * If no receive method, just silently drop it. 2456 * Give preference to the hook over-ride method 2457 */ 2458 if ((!(rcvdata = hook->hk_rcvdata)) 2459 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) { 2460 error = 0; 2461 NG_FREE_ITEM(item); 2462 break; 2463 } 2464 error = (*rcvdata)(hook, item); 2465 break; 2466 case NGQF_MESG: 2467 if (hook) { 2468 if (NG_HOOK_NOT_VALID(hook)) { 2469 /* 2470 * The hook has been zapped then we can't 2471 * use it. Immediately drop its reference. 2472 * The message may not need it. 2473 */ 2474 NG_HOOK_UNREF(hook); 2475 hook = NULL; 2476 } 2477 } 2478 /* 2479 * Similarly, if the node is a zombie there is 2480 * nothing we can do with it, drop everything. 2481 */ 2482 if (NG_NODE_NOT_VALID(node)) { 2483 TRAP_ERROR(); 2484 error = EINVAL; 2485 NG_FREE_ITEM(item); 2486 } else { 2487 /* 2488 * Call the appropriate message handler for the object. 2489 * It is up to the message handler to free the message. 2490 * If it's a generic message, handle it generically, 2491 * otherwise call the type's message handler 2492 * (if it exists) 2493 * XXX (race). Remember that a queued message may 2494 * reference a node or hook that has just been 2495 * invalidated. It will exist as the queue code 2496 * is holding a reference, but.. 2497 */ 2498 2499 struct ng_mesg *msg = NGI_MSG(item); 2500 2501 /* 2502 * check if the generic handler owns it. 2503 */ 2504 if ((msg->header.typecookie == NGM_GENERIC_COOKIE) 2505 && ((msg->header.flags & NGF_RESP) == 0)) { 2506 error = ng_generic_msg(node, item, hook); 2507 break; 2508 } 2509 /* 2510 * Now see if there is a handler (hook or node specific) 2511 * in the target node. If none, silently discard. 2512 */ 2513 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) 2514 && (!(rcvmsg = node->nd_type->rcvmsg))) { 2515 TRAP_ERROR(); 2516 error = 0; 2517 NG_FREE_ITEM(item); 2518 break; 2519 } 2520 error = (*rcvmsg)(node, item, hook); 2521 } 2522 break; 2523 case NGQF_FN: 2524 /* 2525 * We have to implicitly trust the hook, 2526 * as some of these are used for system purposes 2527 * where the hook is invalid. In the case of 2528 * the shutdown message we allow it to hit 2529 * even if the node is invalid. 2530 */ 2531 if ((NG_NODE_NOT_VALID(node)) 2532 && (NGI_FN(item) != &ng_rmnode)) { 2533 TRAP_ERROR(); 2534 error = EINVAL; 2535 NG_FREE_ITEM(item); 2536 break; 2537 } 2538 (*NGI_FN(item))(node, hook, NGI_ARG1(item), NGI_ARG2(item)); 2539 NG_FREE_ITEM(item); 2540 break; 2541 2542 } 2543 /* 2544 * We held references on some of the resources 2545 * that we took from the item. Now that we have 2546 * finished doing everything, drop those references. 2547 */ 2548 if (hook) { 2549 NG_HOOK_UNREF(hook); 2550 } 2551 2552 if (rw == NGQRW_R) { 2553 ng_leave_read(&node->nd_input_queue); 2554 } else { 2555 ng_leave_write(&node->nd_input_queue); 2556 } 2557 2558 /* Apply callback. */ 2559 if (apply != NULL) 2560 (*apply)(context, error); 2561 2562 return (error); 2563 } 2564 2565 /*********************************************************************** 2566 * Implement the 'generic' control messages 2567 ***********************************************************************/ 2568 static int 2569 ng_generic_msg(node_p here, item_p item, hook_p lasthook) 2570 { 2571 int error = 0; 2572 struct ng_mesg *msg; 2573 struct ng_mesg *resp = NULL; 2574 2575 NGI_GET_MSG(item, msg); 2576 if (msg->header.typecookie != NGM_GENERIC_COOKIE) { 2577 TRAP_ERROR(); 2578 error = EINVAL; 2579 goto out; 2580 } 2581 switch (msg->header.cmd) { 2582 case NGM_SHUTDOWN: 2583 ng_rmnode(here, NULL, NULL, 0); 2584 break; 2585 case NGM_MKPEER: 2586 { 2587 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data; 2588 2589 if (msg->header.arglen != sizeof(*mkp)) { 2590 TRAP_ERROR(); 2591 error = EINVAL; 2592 break; 2593 } 2594 mkp->type[sizeof(mkp->type) - 1] = '\0'; 2595 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0'; 2596 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0'; 2597 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type); 2598 break; 2599 } 2600 case NGM_CONNECT: 2601 { 2602 struct ngm_connect *const con = 2603 (struct ngm_connect *) msg->data; 2604 node_p node2; 2605 2606 if (msg->header.arglen != sizeof(*con)) { 2607 TRAP_ERROR(); 2608 error = EINVAL; 2609 break; 2610 } 2611 con->path[sizeof(con->path) - 1] = '\0'; 2612 con->ourhook[sizeof(con->ourhook) - 1] = '\0'; 2613 con->peerhook[sizeof(con->peerhook) - 1] = '\0'; 2614 /* Don't forget we get a reference.. */ 2615 error = ng_path2noderef(here, con->path, &node2, NULL); 2616 if (error) 2617 break; 2618 error = ng_con_nodes(here, con->ourhook, node2, con->peerhook); 2619 NG_NODE_UNREF(node2); 2620 break; 2621 } 2622 case NGM_NAME: 2623 { 2624 struct ngm_name *const nam = (struct ngm_name *) msg->data; 2625 2626 if (msg->header.arglen != sizeof(*nam)) { 2627 TRAP_ERROR(); 2628 error = EINVAL; 2629 break; 2630 } 2631 nam->name[sizeof(nam->name) - 1] = '\0'; 2632 error = ng_name_node(here, nam->name); 2633 break; 2634 } 2635 case NGM_RMHOOK: 2636 { 2637 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data; 2638 hook_p hook; 2639 2640 if (msg->header.arglen != sizeof(*rmh)) { 2641 TRAP_ERROR(); 2642 error = EINVAL; 2643 break; 2644 } 2645 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0'; 2646 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL) 2647 ng_destroy_hook(hook); 2648 break; 2649 } 2650 case NGM_NODEINFO: 2651 { 2652 struct nodeinfo *ni; 2653 2654 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT); 2655 if (resp == NULL) { 2656 error = ENOMEM; 2657 break; 2658 } 2659 2660 /* Fill in node info */ 2661 ni = (struct nodeinfo *) resp->data; 2662 if (NG_NODE_HAS_NAME(here)) 2663 strcpy(ni->name, NG_NODE_NAME(here)); 2664 strcpy(ni->type, here->nd_type->name); 2665 ni->id = ng_node2ID(here); 2666 ni->hooks = here->nd_numhooks; 2667 break; 2668 } 2669 case NGM_LISTHOOKS: 2670 { 2671 const int nhooks = here->nd_numhooks; 2672 struct hooklist *hl; 2673 struct nodeinfo *ni; 2674 hook_p hook; 2675 2676 /* Get response struct */ 2677 NG_MKRESPONSE(resp, msg, sizeof(*hl) 2678 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT); 2679 if (resp == NULL) { 2680 error = ENOMEM; 2681 break; 2682 } 2683 hl = (struct hooklist *) resp->data; 2684 ni = &hl->nodeinfo; 2685 2686 /* Fill in node info */ 2687 if (NG_NODE_HAS_NAME(here)) 2688 strcpy(ni->name, NG_NODE_NAME(here)); 2689 strcpy(ni->type, here->nd_type->name); 2690 ni->id = ng_node2ID(here); 2691 2692 /* Cycle through the linked list of hooks */ 2693 ni->hooks = 0; 2694 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) { 2695 struct linkinfo *const link = &hl->link[ni->hooks]; 2696 2697 if (ni->hooks >= nhooks) { 2698 log(LOG_ERR, "%s: number of %s changed\n", 2699 __func__, "hooks"); 2700 break; 2701 } 2702 if (NG_HOOK_NOT_VALID(hook)) 2703 continue; 2704 strcpy(link->ourhook, NG_HOOK_NAME(hook)); 2705 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook)); 2706 if (NG_PEER_NODE_NAME(hook)[0] != '\0') 2707 strcpy(link->nodeinfo.name, 2708 NG_PEER_NODE_NAME(hook)); 2709 strcpy(link->nodeinfo.type, 2710 NG_PEER_NODE(hook)->nd_type->name); 2711 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook)); 2712 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks; 2713 ni->hooks++; 2714 } 2715 break; 2716 } 2717 2718 case NGM_LISTNAMES: 2719 case NGM_LISTNODES: 2720 { 2721 const int unnamed = (msg->header.cmd == NGM_LISTNODES); 2722 struct namelist *nl; 2723 node_p node; 2724 int num = 0; 2725 2726 mtx_lock(&ng_nodelist_mtx); 2727 /* Count number of nodes */ 2728 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2729 if (NG_NODE_IS_VALID(node) 2730 && (unnamed || NG_NODE_HAS_NAME(node))) { 2731 num++; 2732 } 2733 } 2734 mtx_unlock(&ng_nodelist_mtx); 2735 2736 /* Get response struct */ 2737 NG_MKRESPONSE(resp, msg, sizeof(*nl) 2738 + (num * sizeof(struct nodeinfo)), M_NOWAIT); 2739 if (resp == NULL) { 2740 error = ENOMEM; 2741 break; 2742 } 2743 nl = (struct namelist *) resp->data; 2744 2745 /* Cycle through the linked list of nodes */ 2746 nl->numnames = 0; 2747 mtx_lock(&ng_nodelist_mtx); 2748 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2749 struct nodeinfo *const np = &nl->nodeinfo[nl->numnames]; 2750 2751 if (NG_NODE_NOT_VALID(node)) 2752 continue; 2753 if (!unnamed && (! NG_NODE_HAS_NAME(node))) 2754 continue; 2755 if (nl->numnames >= num) { 2756 log(LOG_ERR, "%s: number of %s changed\n", 2757 __func__, "nodes"); 2758 break; 2759 } 2760 if (NG_NODE_HAS_NAME(node)) 2761 strcpy(np->name, NG_NODE_NAME(node)); 2762 strcpy(np->type, node->nd_type->name); 2763 np->id = ng_node2ID(node); 2764 np->hooks = node->nd_numhooks; 2765 nl->numnames++; 2766 } 2767 mtx_unlock(&ng_nodelist_mtx); 2768 break; 2769 } 2770 2771 case NGM_LISTTYPES: 2772 { 2773 struct typelist *tl; 2774 struct ng_type *type; 2775 int num = 0; 2776 2777 mtx_lock(&ng_typelist_mtx); 2778 /* Count number of types */ 2779 LIST_FOREACH(type, &ng_typelist, types) { 2780 num++; 2781 } 2782 mtx_unlock(&ng_typelist_mtx); 2783 2784 /* Get response struct */ 2785 NG_MKRESPONSE(resp, msg, sizeof(*tl) 2786 + (num * sizeof(struct typeinfo)), M_NOWAIT); 2787 if (resp == NULL) { 2788 error = ENOMEM; 2789 break; 2790 } 2791 tl = (struct typelist *) resp->data; 2792 2793 /* Cycle through the linked list of types */ 2794 tl->numtypes = 0; 2795 mtx_lock(&ng_typelist_mtx); 2796 LIST_FOREACH(type, &ng_typelist, types) { 2797 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes]; 2798 2799 if (tl->numtypes >= num) { 2800 log(LOG_ERR, "%s: number of %s changed\n", 2801 __func__, "types"); 2802 break; 2803 } 2804 strcpy(tp->type_name, type->name); 2805 tp->numnodes = type->refs - 1; /* don't count list */ 2806 tl->numtypes++; 2807 } 2808 mtx_unlock(&ng_typelist_mtx); 2809 break; 2810 } 2811 2812 case NGM_BINARY2ASCII: 2813 { 2814 int bufSize = 20 * 1024; /* XXX hard coded constant */ 2815 const struct ng_parse_type *argstype; 2816 const struct ng_cmdlist *c; 2817 struct ng_mesg *binary, *ascii; 2818 2819 /* Data area must contain a valid netgraph message */ 2820 binary = (struct ng_mesg *)msg->data; 2821 if (msg->header.arglen < sizeof(struct ng_mesg) || 2822 (msg->header.arglen - sizeof(struct ng_mesg) < 2823 binary->header.arglen)) { 2824 TRAP_ERROR(); 2825 error = EINVAL; 2826 break; 2827 } 2828 2829 /* Get a response message with lots of room */ 2830 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT); 2831 if (resp == NULL) { 2832 error = ENOMEM; 2833 break; 2834 } 2835 ascii = (struct ng_mesg *)resp->data; 2836 2837 /* Copy binary message header to response message payload */ 2838 bcopy(binary, ascii, sizeof(*binary)); 2839 2840 /* Find command by matching typecookie and command number */ 2841 for (c = here->nd_type->cmdlist; 2842 c != NULL && c->name != NULL; c++) { 2843 if (binary->header.typecookie == c->cookie 2844 && binary->header.cmd == c->cmd) 2845 break; 2846 } 2847 if (c == NULL || c->name == NULL) { 2848 for (c = ng_generic_cmds; c->name != NULL; c++) { 2849 if (binary->header.typecookie == c->cookie 2850 && binary->header.cmd == c->cmd) 2851 break; 2852 } 2853 if (c->name == NULL) { 2854 NG_FREE_MSG(resp); 2855 error = ENOSYS; 2856 break; 2857 } 2858 } 2859 2860 /* Convert command name to ASCII */ 2861 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr), 2862 "%s", c->name); 2863 2864 /* Convert command arguments to ASCII */ 2865 argstype = (binary->header.flags & NGF_RESP) ? 2866 c->respType : c->mesgType; 2867 if (argstype == NULL) { 2868 *ascii->data = '\0'; 2869 } else { 2870 if ((error = ng_unparse(argstype, 2871 (u_char *)binary->data, 2872 ascii->data, bufSize)) != 0) { 2873 NG_FREE_MSG(resp); 2874 break; 2875 } 2876 } 2877 2878 /* Return the result as struct ng_mesg plus ASCII string */ 2879 bufSize = strlen(ascii->data) + 1; 2880 ascii->header.arglen = bufSize; 2881 resp->header.arglen = sizeof(*ascii) + bufSize; 2882 break; 2883 } 2884 2885 case NGM_ASCII2BINARY: 2886 { 2887 int bufSize = 2000; /* XXX hard coded constant */ 2888 const struct ng_cmdlist *c; 2889 const struct ng_parse_type *argstype; 2890 struct ng_mesg *ascii, *binary; 2891 int off = 0; 2892 2893 /* Data area must contain at least a struct ng_mesg + '\0' */ 2894 ascii = (struct ng_mesg *)msg->data; 2895 if ((msg->header.arglen < sizeof(*ascii) + 1) || 2896 (ascii->header.arglen < 1) || 2897 (msg->header.arglen < sizeof(*ascii) + 2898 ascii->header.arglen)) { 2899 TRAP_ERROR(); 2900 error = EINVAL; 2901 break; 2902 } 2903 ascii->data[ascii->header.arglen - 1] = '\0'; 2904 2905 /* Get a response message with lots of room */ 2906 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT); 2907 if (resp == NULL) { 2908 error = ENOMEM; 2909 break; 2910 } 2911 binary = (struct ng_mesg *)resp->data; 2912 2913 /* Copy ASCII message header to response message payload */ 2914 bcopy(ascii, binary, sizeof(*ascii)); 2915 2916 /* Find command by matching ASCII command string */ 2917 for (c = here->nd_type->cmdlist; 2918 c != NULL && c->name != NULL; c++) { 2919 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2920 break; 2921 } 2922 if (c == NULL || c->name == NULL) { 2923 for (c = ng_generic_cmds; c->name != NULL; c++) { 2924 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2925 break; 2926 } 2927 if (c->name == NULL) { 2928 NG_FREE_MSG(resp); 2929 error = ENOSYS; 2930 break; 2931 } 2932 } 2933 2934 /* Convert command name to binary */ 2935 binary->header.cmd = c->cmd; 2936 binary->header.typecookie = c->cookie; 2937 2938 /* Convert command arguments to binary */ 2939 argstype = (binary->header.flags & NGF_RESP) ? 2940 c->respType : c->mesgType; 2941 if (argstype == NULL) { 2942 bufSize = 0; 2943 } else { 2944 if ((error = ng_parse(argstype, ascii->data, 2945 &off, (u_char *)binary->data, &bufSize)) != 0) { 2946 NG_FREE_MSG(resp); 2947 break; 2948 } 2949 } 2950 2951 /* Return the result */ 2952 binary->header.arglen = bufSize; 2953 resp->header.arglen = sizeof(*binary) + bufSize; 2954 break; 2955 } 2956 2957 case NGM_TEXT_CONFIG: 2958 case NGM_TEXT_STATUS: 2959 /* 2960 * This one is tricky as it passes the command down to the 2961 * actual node, even though it is a generic type command. 2962 * This means we must assume that the item/msg is already freed 2963 * when control passes back to us. 2964 */ 2965 if (here->nd_type->rcvmsg != NULL) { 2966 NGI_MSG(item) = msg; /* put it back as we found it */ 2967 return((*here->nd_type->rcvmsg)(here, item, lasthook)); 2968 } 2969 /* Fall through if rcvmsg not supported */ 2970 default: 2971 TRAP_ERROR(); 2972 error = EINVAL; 2973 } 2974 /* 2975 * Sometimes a generic message may be statically allocated 2976 * to avoid problems with allocating when in tight memeory situations. 2977 * Don't free it if it is so. 2978 * I break them appart here, because erros may cause a free if the item 2979 * in which case we'd be doing it twice. 2980 * they are kept together above, to simplify freeing. 2981 */ 2982 out: 2983 NG_RESPOND_MSG(error, here, item, resp); 2984 if (msg) 2985 NG_FREE_MSG(msg); 2986 return (error); 2987 } 2988 2989 /************************************************************************ 2990 Queue element get/free routines 2991 ************************************************************************/ 2992 2993 uma_zone_t ng_qzone; 2994 static int maxalloc = 512; /* limit the damage of a leak */ 2995 2996 TUNABLE_INT("net.graph.maxalloc", &maxalloc); 2997 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc, 2998 0, "Maximum number of queue items to allocate"); 2999 3000 #ifdef NETGRAPH_DEBUG 3001 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist); 3002 static int allocated; /* number of items malloc'd */ 3003 #endif 3004 3005 /* 3006 * Get a queue entry. 3007 * This is usually called when a packet first enters netgraph. 3008 * By definition, this is usually from an interrupt, or from a user. 3009 * Users are not so important, but try be quick for the times that it's 3010 * an interrupt. 3011 */ 3012 static __inline item_p 3013 ng_getqblk(int flags) 3014 { 3015 item_p item = NULL; 3016 int wait; 3017 3018 wait = (flags & NG_WAITOK) ? M_WAITOK : M_NOWAIT; 3019 3020 item = uma_zalloc(ng_qzone, wait | M_ZERO); 3021 3022 #ifdef NETGRAPH_DEBUG 3023 if (item) { 3024 mtx_lock(&ngq_mtx); 3025 TAILQ_INSERT_TAIL(&ng_itemlist, item, all); 3026 allocated++; 3027 mtx_unlock(&ngq_mtx); 3028 } 3029 #endif 3030 3031 return (item); 3032 } 3033 3034 /* 3035 * Release a queue entry 3036 */ 3037 void 3038 ng_free_item(item_p item) 3039 { 3040 KASSERT(item->apply == NULL, ("%s: leaking apply callback", __func__)); 3041 3042 /* 3043 * The item may hold resources on it's own. We need to free 3044 * these before we can free the item. What they are depends upon 3045 * what kind of item it is. it is important that nodes zero 3046 * out pointers to resources that they remove from the item 3047 * or we release them again here. 3048 */ 3049 switch (item->el_flags & NGQF_TYPE) { 3050 case NGQF_DATA: 3051 /* If we have an mbuf still attached.. */ 3052 NG_FREE_M(_NGI_M(item)); 3053 break; 3054 case NGQF_MESG: 3055 _NGI_RETADDR(item) = 0; 3056 NG_FREE_MSG(_NGI_MSG(item)); 3057 break; 3058 case NGQF_FN: 3059 /* nothing to free really, */ 3060 _NGI_FN(item) = NULL; 3061 _NGI_ARG1(item) = NULL; 3062 _NGI_ARG2(item) = 0; 3063 case NGQF_UNDEF: 3064 break; 3065 } 3066 /* If we still have a node or hook referenced... */ 3067 _NGI_CLR_NODE(item); 3068 _NGI_CLR_HOOK(item); 3069 3070 #ifdef NETGRAPH_DEBUG 3071 mtx_lock(&ngq_mtx); 3072 TAILQ_REMOVE(&ng_itemlist, item, all); 3073 allocated--; 3074 mtx_unlock(&ngq_mtx); 3075 #endif 3076 uma_zfree(ng_qzone, item); 3077 } 3078 3079 /************************************************************************ 3080 Module routines 3081 ************************************************************************/ 3082 3083 /* 3084 * Handle the loading/unloading of a netgraph node type module 3085 */ 3086 int 3087 ng_mod_event(module_t mod, int event, void *data) 3088 { 3089 struct ng_type *const type = data; 3090 int s, error = 0; 3091 3092 switch (event) { 3093 case MOD_LOAD: 3094 3095 /* Register new netgraph node type */ 3096 s = splnet(); 3097 if ((error = ng_newtype(type)) != 0) { 3098 splx(s); 3099 break; 3100 } 3101 3102 /* Call type specific code */ 3103 if (type->mod_event != NULL) 3104 if ((error = (*type->mod_event)(mod, event, data))) { 3105 mtx_lock(&ng_typelist_mtx); 3106 type->refs--; /* undo it */ 3107 LIST_REMOVE(type, types); 3108 mtx_unlock(&ng_typelist_mtx); 3109 } 3110 splx(s); 3111 break; 3112 3113 case MOD_UNLOAD: 3114 s = splnet(); 3115 if (type->refs > 1) { /* make sure no nodes exist! */ 3116 error = EBUSY; 3117 } else { 3118 if (type->refs == 0) { 3119 /* failed load, nothing to undo */ 3120 splx(s); 3121 break; 3122 } 3123 if (type->mod_event != NULL) { /* check with type */ 3124 error = (*type->mod_event)(mod, event, data); 3125 if (error != 0) { /* type refuses.. */ 3126 splx(s); 3127 break; 3128 } 3129 } 3130 mtx_lock(&ng_typelist_mtx); 3131 LIST_REMOVE(type, types); 3132 mtx_unlock(&ng_typelist_mtx); 3133 } 3134 splx(s); 3135 break; 3136 3137 default: 3138 if (type->mod_event != NULL) 3139 error = (*type->mod_event)(mod, event, data); 3140 else 3141 error = EOPNOTSUPP; /* XXX ? */ 3142 break; 3143 } 3144 return (error); 3145 } 3146 3147 /* 3148 * Handle loading and unloading for this code. 3149 * The only thing we need to link into is the NETISR strucure. 3150 */ 3151 static int 3152 ngb_mod_event(module_t mod, int event, void *data) 3153 { 3154 int error = 0; 3155 3156 switch (event) { 3157 case MOD_LOAD: 3158 /* Initialize everything. */ 3159 NG_WORKLIST_LOCK_INIT(); 3160 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL, 3161 MTX_DEF); 3162 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL, 3163 MTX_DEF); 3164 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL, 3165 MTX_DEF); 3166 mtx_init(&ng_topo_mtx, "netgraph topology mutex", NULL, 3167 MTX_DEF); 3168 #ifdef NETGRAPH_DEBUG 3169 mtx_init(&ngq_mtx, "netgraph item list mutex", NULL, 3170 MTX_DEF); 3171 #endif 3172 ng_qzone = uma_zcreate("NetGraph items", sizeof(struct ng_item), 3173 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0); 3174 uma_zone_set_max(ng_qzone, maxalloc); 3175 netisr_register(NETISR_NETGRAPH, (netisr_t *)ngintr, NULL, 3176 NETISR_MPSAFE); 3177 break; 3178 case MOD_UNLOAD: 3179 /* You can't unload it because an interface may be using it. */ 3180 error = EBUSY; 3181 break; 3182 default: 3183 error = EOPNOTSUPP; 3184 break; 3185 } 3186 return (error); 3187 } 3188 3189 static moduledata_t netgraph_mod = { 3190 "netgraph", 3191 ngb_mod_event, 3192 (NULL) 3193 }; 3194 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_MIDDLE); 3195 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family"); 3196 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,""); 3197 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, ""); 3198 3199 #ifdef NETGRAPH_DEBUG 3200 void 3201 dumphook (hook_p hook, char *file, int line) 3202 { 3203 printf("hook: name %s, %d refs, Last touched:\n", 3204 _NG_HOOK_NAME(hook), hook->hk_refs); 3205 printf(" Last active @ %s, line %d\n", 3206 hook->lastfile, hook->lastline); 3207 if (line) { 3208 printf(" problem discovered at file %s, line %d\n", file, line); 3209 } 3210 } 3211 3212 void 3213 dumpnode(node_p node, char *file, int line) 3214 { 3215 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n", 3216 _NG_NODE_ID(node), node->nd_type->name, 3217 node->nd_numhooks, node->nd_flags, 3218 node->nd_refs, node->nd_name); 3219 printf(" Last active @ %s, line %d\n", 3220 node->lastfile, node->lastline); 3221 if (line) { 3222 printf(" problem discovered at file %s, line %d\n", file, line); 3223 } 3224 } 3225 3226 void 3227 dumpitem(item_p item, char *file, int line) 3228 { 3229 printf(" ACTIVE item, last used at %s, line %d", 3230 item->lastfile, item->lastline); 3231 switch(item->el_flags & NGQF_TYPE) { 3232 case NGQF_DATA: 3233 printf(" - [data]\n"); 3234 break; 3235 case NGQF_MESG: 3236 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item)); 3237 break; 3238 case NGQF_FN: 3239 printf(" - fn@%p (%p, %p, %p, %d (%x))\n", 3240 item->body.fn.fn_fn, 3241 _NGI_NODE(item), 3242 _NGI_HOOK(item), 3243 item->body.fn.fn_arg1, 3244 item->body.fn.fn_arg2, 3245 item->body.fn.fn_arg2); 3246 break; 3247 case NGQF_UNDEF: 3248 printf(" - UNDEFINED!\n"); 3249 } 3250 if (line) { 3251 printf(" problem discovered at file %s, line %d\n", file, line); 3252 if (_NGI_NODE(item)) { 3253 printf("node %p ([%x])\n", 3254 _NGI_NODE(item), ng_node2ID(_NGI_NODE(item))); 3255 } 3256 } 3257 } 3258 3259 static void 3260 ng_dumpitems(void) 3261 { 3262 item_p item; 3263 int i = 1; 3264 TAILQ_FOREACH(item, &ng_itemlist, all) { 3265 printf("[%d] ", i++); 3266 dumpitem(item, NULL, 0); 3267 } 3268 } 3269 3270 static void 3271 ng_dumpnodes(void) 3272 { 3273 node_p node; 3274 int i = 1; 3275 mtx_lock(&ng_nodelist_mtx); 3276 SLIST_FOREACH(node, &ng_allnodes, nd_all) { 3277 printf("[%d] ", i++); 3278 dumpnode(node, NULL, 0); 3279 } 3280 mtx_unlock(&ng_nodelist_mtx); 3281 } 3282 3283 static void 3284 ng_dumphooks(void) 3285 { 3286 hook_p hook; 3287 int i = 1; 3288 mtx_lock(&ng_nodelist_mtx); 3289 SLIST_FOREACH(hook, &ng_allhooks, hk_all) { 3290 printf("[%d] ", i++); 3291 dumphook(hook, NULL, 0); 3292 } 3293 mtx_unlock(&ng_nodelist_mtx); 3294 } 3295 3296 static int 3297 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS) 3298 { 3299 int error; 3300 int val; 3301 int i; 3302 3303 val = allocated; 3304 i = 1; 3305 error = sysctl_handle_int(oidp, &val, 0, req); 3306 if (error != 0 || req->newptr == NULL) 3307 return (error); 3308 if (val == 42) { 3309 ng_dumpitems(); 3310 ng_dumpnodes(); 3311 ng_dumphooks(); 3312 } 3313 return (0); 3314 } 3315 3316 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW, 3317 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items"); 3318 #endif /* NETGRAPH_DEBUG */ 3319 3320 3321 /*********************************************************************** 3322 * Worklist routines 3323 **********************************************************************/ 3324 /* NETISR thread enters here */ 3325 /* 3326 * Pick a node off the list of nodes with work, 3327 * try get an item to process off it. 3328 * If there are no more, remove the node from the list. 3329 */ 3330 static void 3331 ngintr(void) 3332 { 3333 item_p item; 3334 node_p node = NULL; 3335 3336 for (;;) { 3337 NG_WORKLIST_LOCK(); 3338 node = TAILQ_FIRST(&ng_worklist); 3339 if (!node) { 3340 NG_WORKLIST_UNLOCK(); 3341 break; 3342 } 3343 node->nd_flags &= ~NGF_WORKQ; 3344 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3345 NG_WORKLIST_UNLOCK(); 3346 CTR3(KTR_NET, "%20s: node [%x] (%p) taken off worklist", 3347 __func__, node->nd_ID, node); 3348 /* 3349 * We have the node. We also take over the reference 3350 * that the list had on it. 3351 * Now process as much as you can, until it won't 3352 * let you have another item off the queue. 3353 * All this time, keep the reference 3354 * that lets us be sure that the node still exists. 3355 * Let the reference go at the last minute. 3356 * ng_dequeue will put us back on the worklist 3357 * if there is more too do. This may be of use if there 3358 * are Multiple Processors and multiple Net threads in the 3359 * future. 3360 */ 3361 for (;;) { 3362 int rw; 3363 3364 NG_QUEUE_LOCK(&node->nd_input_queue); 3365 item = ng_dequeue(&node->nd_input_queue, &rw); 3366 if (item == NULL) { 3367 NG_QUEUE_UNLOCK(&node->nd_input_queue); 3368 break; /* go look for another node */ 3369 } else { 3370 NG_QUEUE_UNLOCK(&node->nd_input_queue); 3371 NGI_GET_NODE(item, node); /* zaps stored node */ 3372 ng_apply_item(node, item, rw); 3373 NG_NODE_UNREF(node); 3374 } 3375 } 3376 NG_NODE_UNREF(node); 3377 } 3378 } 3379 3380 static void 3381 ng_worklist_remove(node_p node) 3382 { 3383 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED); 3384 3385 NG_WORKLIST_LOCK(); 3386 if (node->nd_flags & NGF_WORKQ) { 3387 node->nd_flags &= ~NGF_WORKQ; 3388 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3389 NG_WORKLIST_UNLOCK(); 3390 NG_NODE_UNREF(node); 3391 CTR3(KTR_NET, "%20s: node [%x] (%p) removed from worklist", 3392 __func__, node->nd_ID, node); 3393 } else { 3394 NG_WORKLIST_UNLOCK(); 3395 } 3396 } 3397 3398 /* 3399 * XXX 3400 * It's posible that a debugging NG_NODE_REF may need 3401 * to be outside the mutex zone 3402 */ 3403 static void 3404 ng_setisr(node_p node) 3405 { 3406 3407 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED); 3408 3409 if ((node->nd_flags & NGF_WORKQ) == 0) { 3410 /* 3411 * If we are not already on the work queue, 3412 * then put us on. 3413 */ 3414 node->nd_flags |= NGF_WORKQ; 3415 NG_WORKLIST_LOCK(); 3416 TAILQ_INSERT_TAIL(&ng_worklist, node, nd_work); 3417 NG_WORKLIST_UNLOCK(); 3418 NG_NODE_REF(node); /* XXX fafe in mutex? */ 3419 CTR3(KTR_NET, "%20s: node [%x] (%p) put on worklist", __func__, 3420 node->nd_ID, node); 3421 } else 3422 CTR3(KTR_NET, "%20s: node [%x] (%p) already on worklist", 3423 __func__, node->nd_ID, node); 3424 schednetisr(NETISR_NETGRAPH); 3425 } 3426 3427 3428 /*********************************************************************** 3429 * Externally useable functions to set up a queue item ready for sending 3430 ***********************************************************************/ 3431 3432 #ifdef NETGRAPH_DEBUG 3433 #define ITEM_DEBUG_CHECKS \ 3434 do { \ 3435 if (NGI_NODE(item) ) { \ 3436 printf("item already has node"); \ 3437 kdb_enter("has node"); \ 3438 NGI_CLR_NODE(item); \ 3439 } \ 3440 if (NGI_HOOK(item) ) { \ 3441 printf("item already has hook"); \ 3442 kdb_enter("has hook"); \ 3443 NGI_CLR_HOOK(item); \ 3444 } \ 3445 } while (0) 3446 #else 3447 #define ITEM_DEBUG_CHECKS 3448 #endif 3449 3450 /* 3451 * Put mbuf into the item. 3452 * Hook and node references will be removed when the item is dequeued. 3453 * (or equivalent) 3454 * (XXX) Unsafe because no reference held by peer on remote node. 3455 * remote node might go away in this timescale. 3456 * We know the hooks can't go away because that would require getting 3457 * a writer item on both nodes and we must have at least a reader 3458 * here to be able to do this. 3459 * Note that the hook loaded is the REMOTE hook. 3460 * 3461 * This is possibly in the critical path for new data. 3462 */ 3463 item_p 3464 ng_package_data(struct mbuf *m, int flags) 3465 { 3466 item_p item; 3467 3468 if ((item = ng_getqblk(flags)) == NULL) { 3469 NG_FREE_M(m); 3470 return (NULL); 3471 } 3472 ITEM_DEBUG_CHECKS; 3473 item->el_flags = NGQF_DATA | NGQF_READER; 3474 item->el_next = NULL; 3475 NGI_M(item) = m; 3476 return (item); 3477 } 3478 3479 /* 3480 * Allocate a queue item and put items into it.. 3481 * Evaluate the address as this will be needed to queue it and 3482 * to work out what some of the fields should be. 3483 * Hook and node references will be removed when the item is dequeued. 3484 * (or equivalent) 3485 */ 3486 item_p 3487 ng_package_msg(struct ng_mesg *msg, int flags) 3488 { 3489 item_p item; 3490 3491 if ((item = ng_getqblk(flags)) == NULL) { 3492 NG_FREE_MSG(msg); 3493 return (NULL); 3494 } 3495 ITEM_DEBUG_CHECKS; 3496 /* Messages items count as writers unless explicitly exempted. */ 3497 if (msg->header.cmd & NGM_READONLY) 3498 item->el_flags = NGQF_MESG | NGQF_READER; 3499 else 3500 item->el_flags = NGQF_MESG | NGQF_WRITER; 3501 item->el_next = NULL; 3502 /* 3503 * Set the current lasthook into the queue item 3504 */ 3505 NGI_MSG(item) = msg; 3506 NGI_RETADDR(item) = 0; 3507 return (item); 3508 } 3509 3510 3511 3512 #define SET_RETADDR(item, here, retaddr) \ 3513 do { /* Data or fn items don't have retaddrs */ \ 3514 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \ 3515 if (retaddr) { \ 3516 NGI_RETADDR(item) = retaddr; \ 3517 } else { \ 3518 /* \ 3519 * The old return address should be ok. \ 3520 * If there isn't one, use the address \ 3521 * here. \ 3522 */ \ 3523 if (NGI_RETADDR(item) == 0) { \ 3524 NGI_RETADDR(item) \ 3525 = ng_node2ID(here); \ 3526 } \ 3527 } \ 3528 } \ 3529 } while (0) 3530 3531 int 3532 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr) 3533 { 3534 hook_p peer; 3535 node_p peernode; 3536 ITEM_DEBUG_CHECKS; 3537 /* 3538 * Quick sanity check.. 3539 * Since a hook holds a reference on it's node, once we know 3540 * that the peer is still connected (even if invalid,) we know 3541 * that the peer node is present, though maybe invalid. 3542 */ 3543 if ((hook == NULL) 3544 || NG_HOOK_NOT_VALID(hook) 3545 || (NG_HOOK_PEER(hook) == NULL) 3546 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)) 3547 || NG_NODE_NOT_VALID(NG_PEER_NODE(hook))) { 3548 NG_FREE_ITEM(item); 3549 TRAP_ERROR(); 3550 return (ENETDOWN); 3551 } 3552 3553 /* 3554 * Transfer our interest to the other (peer) end. 3555 */ 3556 peer = NG_HOOK_PEER(hook); 3557 NG_HOOK_REF(peer); 3558 NGI_SET_HOOK(item, peer); 3559 peernode = NG_PEER_NODE(hook); 3560 NG_NODE_REF(peernode); 3561 NGI_SET_NODE(item, peernode); 3562 SET_RETADDR(item, here, retaddr); 3563 return (0); 3564 } 3565 3566 int 3567 ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr) 3568 { 3569 node_p dest = NULL; 3570 hook_p hook = NULL; 3571 int error; 3572 3573 ITEM_DEBUG_CHECKS; 3574 /* 3575 * Note that ng_path2noderef increments the reference count 3576 * on the node for us if it finds one. So we don't have to. 3577 */ 3578 error = ng_path2noderef(here, address, &dest, &hook); 3579 if (error) { 3580 NG_FREE_ITEM(item); 3581 return (error); 3582 } 3583 NGI_SET_NODE(item, dest); 3584 if ( hook) { 3585 NG_HOOK_REF(hook); /* don't let it go while on the queue */ 3586 NGI_SET_HOOK(item, hook); 3587 } 3588 SET_RETADDR(item, here, retaddr); 3589 return (0); 3590 } 3591 3592 int 3593 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr) 3594 { 3595 node_p dest; 3596 3597 ITEM_DEBUG_CHECKS; 3598 /* 3599 * Find the target node. 3600 */ 3601 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */ 3602 if (dest == NULL) { 3603 NG_FREE_ITEM(item); 3604 TRAP_ERROR(); 3605 return(EINVAL); 3606 } 3607 /* Fill out the contents */ 3608 NGI_SET_NODE(item, dest); 3609 NGI_CLR_HOOK(item); 3610 SET_RETADDR(item, here, retaddr); 3611 return (0); 3612 } 3613 3614 /* 3615 * special case to send a message to self (e.g. destroy node) 3616 * Possibly indicate an arrival hook too. 3617 * Useful for removing that hook :-) 3618 */ 3619 item_p 3620 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg) 3621 { 3622 item_p item; 3623 3624 /* 3625 * Find the target node. 3626 * If there is a HOOK argument, then use that in preference 3627 * to the address. 3628 */ 3629 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL) { 3630 NG_FREE_MSG(msg); 3631 return (NULL); 3632 } 3633 3634 /* Fill out the contents */ 3635 item->el_flags = NGQF_MESG | NGQF_WRITER; 3636 item->el_next = NULL; 3637 NG_NODE_REF(here); 3638 NGI_SET_NODE(item, here); 3639 if (hook) { 3640 NG_HOOK_REF(hook); 3641 NGI_SET_HOOK(item, hook); 3642 } 3643 NGI_MSG(item) = msg; 3644 NGI_RETADDR(item) = ng_node2ID(here); 3645 return (item); 3646 } 3647 3648 int 3649 ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2, 3650 int flags) 3651 { 3652 item_p item; 3653 3654 if ((item = ng_getqblk(flags)) == NULL) { 3655 return (ENOMEM); 3656 } 3657 item->el_flags = NGQF_FN | NGQF_WRITER; 3658 NG_NODE_REF(node); /* and one for the item */ 3659 NGI_SET_NODE(item, node); 3660 if (hook) { 3661 NG_HOOK_REF(hook); 3662 NGI_SET_HOOK(item, hook); 3663 } 3664 NGI_FN(item) = fn; 3665 NGI_ARG1(item) = arg1; 3666 NGI_ARG2(item) = arg2; 3667 return(ng_snd_item(item, flags)); 3668 } 3669 3670 /* 3671 * Official timeout routines for Netgraph nodes. 3672 */ 3673 static void 3674 ng_callout_trampoline(void *arg) 3675 { 3676 item_p item = arg; 3677 3678 ng_snd_item(item, 0); 3679 } 3680 3681 3682 int 3683 ng_callout(struct callout *c, node_p node, hook_p hook, int ticks, 3684 ng_item_fn *fn, void * arg1, int arg2) 3685 { 3686 item_p item, oitem; 3687 3688 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL) 3689 return (ENOMEM); 3690 3691 item->el_flags = NGQF_FN | NGQF_WRITER; 3692 NG_NODE_REF(node); /* and one for the item */ 3693 NGI_SET_NODE(item, node); 3694 if (hook) { 3695 NG_HOOK_REF(hook); 3696 NGI_SET_HOOK(item, hook); 3697 } 3698 NGI_FN(item) = fn; 3699 NGI_ARG1(item) = arg1; 3700 NGI_ARG2(item) = arg2; 3701 oitem = c->c_arg; 3702 if (callout_reset(c, ticks, &ng_callout_trampoline, item) == 1 && 3703 oitem != NULL) 3704 NG_FREE_ITEM(oitem); 3705 return (0); 3706 } 3707 3708 /* A special modified version of untimeout() */ 3709 int 3710 ng_uncallout(struct callout *c, node_p node) 3711 { 3712 item_p item; 3713 int rval; 3714 3715 KASSERT(c != NULL, ("ng_uncallout: NULL callout")); 3716 KASSERT(node != NULL, ("ng_uncallout: NULL node")); 3717 3718 rval = callout_stop(c); 3719 item = c->c_arg; 3720 /* Do an extra check */ 3721 if ((rval > 0) && (c->c_func == &ng_callout_trampoline) && 3722 (NGI_NODE(item) == node)) { 3723 /* 3724 * We successfully removed it from the queue before it ran 3725 * So now we need to unreference everything that was 3726 * given extra references. (NG_FREE_ITEM does this). 3727 */ 3728 NG_FREE_ITEM(item); 3729 } 3730 c->c_arg = NULL; 3731 3732 return (rval); 3733 } 3734 3735 /* 3736 * Set the address, if none given, give the node here. 3737 */ 3738 void 3739 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr) 3740 { 3741 if (retaddr) { 3742 NGI_RETADDR(item) = retaddr; 3743 } else { 3744 /* 3745 * The old return address should be ok. 3746 * If there isn't one, use the address here. 3747 */ 3748 NGI_RETADDR(item) = ng_node2ID(here); 3749 } 3750 } 3751 3752 #define TESTING 3753 #ifdef TESTING 3754 /* just test all the macros */ 3755 void 3756 ng_macro_test(item_p item); 3757 void 3758 ng_macro_test(item_p item) 3759 { 3760 node_p node = NULL; 3761 hook_p hook = NULL; 3762 struct mbuf *m; 3763 struct ng_mesg *msg; 3764 ng_ID_t retaddr; 3765 int error; 3766 3767 NGI_GET_M(item, m); 3768 NGI_GET_MSG(item, msg); 3769 retaddr = NGI_RETADDR(item); 3770 NG_SEND_DATA(error, hook, m, NULL); 3771 NG_SEND_DATA_ONLY(error, hook, m); 3772 NG_FWD_NEW_DATA(error, item, hook, m); 3773 NG_FWD_ITEM_HOOK(error, item, hook); 3774 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr); 3775 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr); 3776 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr); 3777 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr); 3778 } 3779 #endif /* TESTING */ 3780 3781