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sys/netgraph/ng_base.c
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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: releng/6.1/sys/netgraph/ng_base.c 154613 2006-01-21 09:59:43Z glebius $ 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 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/ 232 /* 233 * In debug mode: 234 * In an attempt to help track reference count screwups 235 * we do not free objects back to the malloc system, but keep them 236 * in a local cache where we can examine them and keep information safely 237 * after they have been freed. 238 * We use this scheme for nodes and hooks, and to some extent for items. 239 */ 240 static __inline hook_p 241 ng_alloc_hook(void) 242 { 243 hook_p hook; 244 SLIST_ENTRY(ng_hook) temp; 245 mtx_lock(&ng_nodelist_mtx); 246 hook = LIST_FIRST(&ng_freehooks); 247 if (hook) { 248 LIST_REMOVE(hook, hk_hooks); 249 bcopy(&hook->hk_all, &temp, sizeof(temp)); 250 bzero(hook, sizeof(struct ng_hook)); 251 bcopy(&temp, &hook->hk_all, sizeof(temp)); 252 mtx_unlock(&ng_nodelist_mtx); 253 hook->hk_magic = HK_MAGIC; 254 } else { 255 mtx_unlock(&ng_nodelist_mtx); 256 _NG_ALLOC_HOOK(hook); 257 if (hook) { 258 hook->hk_magic = HK_MAGIC; 259 mtx_lock(&ng_nodelist_mtx); 260 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all); 261 mtx_unlock(&ng_nodelist_mtx); 262 } 263 } 264 return (hook); 265 } 266 267 static __inline node_p 268 ng_alloc_node(void) 269 { 270 node_p node; 271 SLIST_ENTRY(ng_node) temp; 272 mtx_lock(&ng_nodelist_mtx); 273 node = LIST_FIRST(&ng_freenodes); 274 if (node) { 275 LIST_REMOVE(node, nd_nodes); 276 bcopy(&node->nd_all, &temp, sizeof(temp)); 277 bzero(node, sizeof(struct ng_node)); 278 bcopy(&temp, &node->nd_all, sizeof(temp)); 279 mtx_unlock(&ng_nodelist_mtx); 280 node->nd_magic = ND_MAGIC; 281 } else { 282 mtx_unlock(&ng_nodelist_mtx); 283 _NG_ALLOC_NODE(node); 284 if (node) { 285 node->nd_magic = ND_MAGIC; 286 mtx_lock(&ng_nodelist_mtx); 287 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all); 288 mtx_unlock(&ng_nodelist_mtx); 289 } 290 } 291 return (node); 292 } 293 294 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0) 295 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0) 296 297 298 #define NG_FREE_HOOK(hook) \ 299 do { \ 300 mtx_lock(&ng_nodelist_mtx); \ 301 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \ 302 hook->hk_magic = 0; \ 303 mtx_unlock(&ng_nodelist_mtx); \ 304 } while (0) 305 306 #define NG_FREE_NODE(node) \ 307 do { \ 308 mtx_lock(&ng_nodelist_mtx); \ 309 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \ 310 node->nd_magic = 0; \ 311 mtx_unlock(&ng_nodelist_mtx); \ 312 } while (0) 313 314 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 315 316 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook) 317 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node) 318 319 #define NG_FREE_HOOK(hook) do { FREE((hook), M_NETGRAPH_HOOK); } while (0) 320 #define NG_FREE_NODE(node) do { FREE((node), M_NETGRAPH_NODE); } while (0) 321 322 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 323 324 /* Set this to kdb_enter("X") to catch all errors as they occur */ 325 #ifndef TRAP_ERROR 326 #define TRAP_ERROR() 327 #endif 328 329 static ng_ID_t nextID = 1; 330 331 #ifdef INVARIANTS 332 #define CHECK_DATA_MBUF(m) do { \ 333 struct mbuf *n; \ 334 int total; \ 335 \ 336 M_ASSERTPKTHDR(m); \ 337 for (total = 0, n = (m); n != NULL; n = n->m_next) { \ 338 total += n->m_len; \ 339 if (n->m_nextpkt != NULL) \ 340 panic("%s: m_nextpkt", __func__); \ 341 } \ 342 \ 343 if ((m)->m_pkthdr.len != total) { \ 344 panic("%s: %d != %d", \ 345 __func__, (m)->m_pkthdr.len, total); \ 346 } \ 347 } while (0) 348 #else 349 #define CHECK_DATA_MBUF(m) 350 #endif 351 352 353 /************************************************************************ 354 Parse type definitions for generic messages 355 ************************************************************************/ 356 357 /* Handy structure parse type defining macro */ 358 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \ 359 static const struct ng_parse_struct_field \ 360 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \ 361 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \ 362 &ng_parse_struct_type, \ 363 &ng_ ## lo ## _type_fields \ 364 } 365 366 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ()); 367 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ()); 368 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ()); 369 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ()); 370 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ()); 371 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ()); 372 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type)); 373 374 /* Get length of an array when the length is stored as a 32 bit 375 value immediately preceding the array -- as with struct namelist 376 and struct typelist. */ 377 static int 378 ng_generic_list_getLength(const struct ng_parse_type *type, 379 const u_char *start, const u_char *buf) 380 { 381 return *((const u_int32_t *)(buf - 4)); 382 } 383 384 /* Get length of the array of struct linkinfo inside a struct hooklist */ 385 static int 386 ng_generic_linkinfo_getLength(const struct ng_parse_type *type, 387 const u_char *start, const u_char *buf) 388 { 389 const struct hooklist *hl = (const struct hooklist *)start; 390 391 return hl->nodeinfo.hooks; 392 } 393 394 /* Array type for a variable length array of struct namelist */ 395 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = { 396 &ng_generic_nodeinfo_type, 397 &ng_generic_list_getLength 398 }; 399 static const struct ng_parse_type ng_generic_nodeinfoarray_type = { 400 &ng_parse_array_type, 401 &ng_nodeinfoarray_type_info 402 }; 403 404 /* Array type for a variable length array of struct typelist */ 405 static const struct ng_parse_array_info ng_typeinfoarray_type_info = { 406 &ng_generic_typeinfo_type, 407 &ng_generic_list_getLength 408 }; 409 static const struct ng_parse_type ng_generic_typeinfoarray_type = { 410 &ng_parse_array_type, 411 &ng_typeinfoarray_type_info 412 }; 413 414 /* Array type for array of struct linkinfo in struct hooklist */ 415 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = { 416 &ng_generic_linkinfo_type, 417 &ng_generic_linkinfo_getLength 418 }; 419 static const struct ng_parse_type ng_generic_linkinfo_array_type = { 420 &ng_parse_array_type, 421 &ng_generic_linkinfo_array_type_info 422 }; 423 424 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type)); 425 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST, 426 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type)); 427 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES, 428 (&ng_generic_nodeinfoarray_type)); 429 430 /* List of commands and how to convert arguments to/from ASCII */ 431 static const struct ng_cmdlist ng_generic_cmds[] = { 432 { 433 NGM_GENERIC_COOKIE, 434 NGM_SHUTDOWN, 435 "shutdown", 436 NULL, 437 NULL 438 }, 439 { 440 NGM_GENERIC_COOKIE, 441 NGM_MKPEER, 442 "mkpeer", 443 &ng_generic_mkpeer_type, 444 NULL 445 }, 446 { 447 NGM_GENERIC_COOKIE, 448 NGM_CONNECT, 449 "connect", 450 &ng_generic_connect_type, 451 NULL 452 }, 453 { 454 NGM_GENERIC_COOKIE, 455 NGM_NAME, 456 "name", 457 &ng_generic_name_type, 458 NULL 459 }, 460 { 461 NGM_GENERIC_COOKIE, 462 NGM_RMHOOK, 463 "rmhook", 464 &ng_generic_rmhook_type, 465 NULL 466 }, 467 { 468 NGM_GENERIC_COOKIE, 469 NGM_NODEINFO, 470 "nodeinfo", 471 NULL, 472 &ng_generic_nodeinfo_type 473 }, 474 { 475 NGM_GENERIC_COOKIE, 476 NGM_LISTHOOKS, 477 "listhooks", 478 NULL, 479 &ng_generic_hooklist_type 480 }, 481 { 482 NGM_GENERIC_COOKIE, 483 NGM_LISTNAMES, 484 "listnames", 485 NULL, 486 &ng_generic_listnodes_type /* same as NGM_LISTNODES */ 487 }, 488 { 489 NGM_GENERIC_COOKIE, 490 NGM_LISTNODES, 491 "listnodes", 492 NULL, 493 &ng_generic_listnodes_type 494 }, 495 { 496 NGM_GENERIC_COOKIE, 497 NGM_LISTTYPES, 498 "listtypes", 499 NULL, 500 &ng_generic_typeinfo_type 501 }, 502 { 503 NGM_GENERIC_COOKIE, 504 NGM_TEXT_CONFIG, 505 "textconfig", 506 NULL, 507 &ng_parse_string_type 508 }, 509 { 510 NGM_GENERIC_COOKIE, 511 NGM_TEXT_STATUS, 512 "textstatus", 513 NULL, 514 &ng_parse_string_type 515 }, 516 { 517 NGM_GENERIC_COOKIE, 518 NGM_ASCII2BINARY, 519 "ascii2binary", 520 &ng_parse_ng_mesg_type, 521 &ng_parse_ng_mesg_type 522 }, 523 { 524 NGM_GENERIC_COOKIE, 525 NGM_BINARY2ASCII, 526 "binary2ascii", 527 &ng_parse_ng_mesg_type, 528 &ng_parse_ng_mesg_type 529 }, 530 { 0 } 531 }; 532 533 /************************************************************************ 534 Node routines 535 ************************************************************************/ 536 537 /* 538 * Instantiate a node of the requested type 539 */ 540 int 541 ng_make_node(const char *typename, node_p *nodepp) 542 { 543 struct ng_type *type; 544 int error; 545 546 /* Check that the type makes sense */ 547 if (typename == NULL) { 548 TRAP_ERROR(); 549 return (EINVAL); 550 } 551 552 /* Locate the node type. If we fail we return. Do not try to load 553 * module. 554 */ 555 if ((type = ng_findtype(typename)) == NULL) 556 return (ENXIO); 557 558 /* 559 * If we have a constructor, then make the node and 560 * call the constructor to do type specific initialisation. 561 */ 562 if (type->constructor != NULL) { 563 if ((error = ng_make_node_common(type, nodepp)) == 0) { 564 if ((error = ((*type->constructor)(*nodepp)) != 0)) { 565 NG_NODE_UNREF(*nodepp); 566 } 567 } 568 } else { 569 /* 570 * Node has no constructor. We cannot ask for one 571 * to be made. It must be brought into existance by 572 * some external agency. The external agency should 573 * call ng_make_node_common() directly to get the 574 * netgraph part initialised. 575 */ 576 TRAP_ERROR(); 577 error = EINVAL; 578 } 579 return (error); 580 } 581 582 /* 583 * Generic node creation. Called by node initialisation for externally 584 * instantiated nodes (e.g. hardware, sockets, etc ). 585 * The returned node has a reference count of 1. 586 */ 587 int 588 ng_make_node_common(struct ng_type *type, node_p *nodepp) 589 { 590 node_p node; 591 592 /* Require the node type to have been already installed */ 593 if (ng_findtype(type->name) == NULL) { 594 TRAP_ERROR(); 595 return (EINVAL); 596 } 597 598 /* Make a node and try attach it to the type */ 599 NG_ALLOC_NODE(node); 600 if (node == NULL) { 601 TRAP_ERROR(); 602 return (ENOMEM); 603 } 604 node->nd_type = type; 605 NG_NODE_REF(node); /* note reference */ 606 type->refs++; 607 608 mtx_init(&node->nd_input_queue.q_mtx, "ng_node", NULL, MTX_SPIN); 609 node->nd_input_queue.queue = NULL; 610 node->nd_input_queue.last = &node->nd_input_queue.queue; 611 node->nd_input_queue.q_flags = 0; 612 node->nd_input_queue.q_node = node; 613 614 /* Initialize hook list for new node */ 615 LIST_INIT(&node->nd_hooks); 616 617 /* Link us into the node linked list */ 618 mtx_lock(&ng_nodelist_mtx); 619 LIST_INSERT_HEAD(&ng_nodelist, node, nd_nodes); 620 mtx_unlock(&ng_nodelist_mtx); 621 622 623 /* get an ID and put us in the hash chain */ 624 mtx_lock(&ng_idhash_mtx); 625 for (;;) { /* wrap protection, even if silly */ 626 node_p node2 = NULL; 627 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */ 628 629 /* Is there a problem with the new number? */ 630 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */ 631 if ((node->nd_ID != 0) && (node2 == NULL)) { 632 break; 633 } 634 } 635 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)], 636 node, nd_idnodes); 637 mtx_unlock(&ng_idhash_mtx); 638 639 /* Done */ 640 *nodepp = node; 641 return (0); 642 } 643 644 /* 645 * Forceably start the shutdown process on a node. Either call 646 * it's shutdown method, or do the default shutdown if there is 647 * no type-specific method. 648 * 649 * We can only be called form a shutdown message, so we know we have 650 * a writer lock, and therefore exclusive access. It also means 651 * that we should not be on the work queue, but we check anyhow. 652 * 653 * Persistent node types must have a type-specific method which 654 * Allocates a new node in which case, this one is irretrievably going away, 655 * or cleans up anything it needs, and just makes the node valid again, 656 * in which case we allow the node to survive. 657 * 658 * XXX We need to think of how to tell a persistant node that we 659 * REALLY need to go away because the hardware has gone or we 660 * are rebooting.... etc. 661 */ 662 void 663 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3) 664 { 665 hook_p hook; 666 667 /* Check if it's already shutting down */ 668 if ((node->nd_flags & NGF_CLOSING) != 0) 669 return; 670 671 if (node == &ng_deadnode) { 672 printf ("shutdown called on deadnode\n"); 673 return; 674 } 675 676 /* Add an extra reference so it doesn't go away during this */ 677 NG_NODE_REF(node); 678 679 /* 680 * Mark it invalid so any newcomers know not to try use it 681 * Also add our own mark so we can't recurse 682 * note that NGF_INVALID does not do this as it's also set during 683 * creation 684 */ 685 node->nd_flags |= NGF_INVALID|NGF_CLOSING; 686 687 /* If node has its pre-shutdown method, then call it first*/ 688 if (node->nd_type && node->nd_type->close) 689 (*node->nd_type->close)(node); 690 691 /* Notify all remaining connected nodes to disconnect */ 692 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL) 693 ng_destroy_hook(hook); 694 695 /* 696 * Drain the input queue forceably. 697 * it has no hooks so what's it going to do, bleed on someone? 698 * Theoretically we came here from a queue entry that was added 699 * Just before the queue was closed, so it should be empty anyway. 700 * Also removes us from worklist if needed. 701 */ 702 ng_flush_input_queue(&node->nd_input_queue); 703 704 /* Ask the type if it has anything to do in this case */ 705 if (node->nd_type && node->nd_type->shutdown) { 706 (*node->nd_type->shutdown)(node); 707 if (NG_NODE_IS_VALID(node)) { 708 /* 709 * Well, blow me down if the node code hasn't declared 710 * that it doesn't want to die. 711 * Presumably it is a persistant node. 712 * If we REALLY want it to go away, 713 * e.g. hardware going away, 714 * Our caller should set NGF_REALLY_DIE in nd_flags. 715 */ 716 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING); 717 NG_NODE_UNREF(node); /* Assume they still have theirs */ 718 return; 719 } 720 } else { /* do the default thing */ 721 NG_NODE_UNREF(node); 722 } 723 724 ng_unname(node); /* basically a NOP these days */ 725 726 /* 727 * Remove extra reference, possibly the last 728 * Possible other holders of references may include 729 * timeout callouts, but theoretically the node's supposed to 730 * have cancelled them. Possibly hardware dependencies may 731 * force a driver to 'linger' with a reference. 732 */ 733 NG_NODE_UNREF(node); 734 } 735 736 /* 737 * Remove a reference to the node, possibly the last. 738 * deadnode always acts as it it were the last. 739 */ 740 int 741 ng_unref_node(node_p node) 742 { 743 int v; 744 745 if (node == &ng_deadnode) { 746 return (0); 747 } 748 749 do { 750 v = node->nd_refs - 1; 751 } while (! atomic_cmpset_int(&node->nd_refs, v + 1, v)); 752 753 if (v == 0) { /* we were the last */ 754 755 mtx_lock(&ng_nodelist_mtx); 756 node->nd_type->refs--; /* XXX maybe should get types lock? */ 757 LIST_REMOVE(node, nd_nodes); 758 mtx_unlock(&ng_nodelist_mtx); 759 760 mtx_lock(&ng_idhash_mtx); 761 LIST_REMOVE(node, nd_idnodes); 762 mtx_unlock(&ng_idhash_mtx); 763 764 mtx_destroy(&node->nd_input_queue.q_mtx); 765 NG_FREE_NODE(node); 766 } 767 return (v); 768 } 769 770 /************************************************************************ 771 Node ID handling 772 ************************************************************************/ 773 static node_p 774 ng_ID2noderef(ng_ID_t ID) 775 { 776 node_p node; 777 mtx_lock(&ng_idhash_mtx); 778 NG_IDHASH_FIND(ID, node); 779 if(node) 780 NG_NODE_REF(node); 781 mtx_unlock(&ng_idhash_mtx); 782 return(node); 783 } 784 785 ng_ID_t 786 ng_node2ID(node_p node) 787 { 788 return (node ? NG_NODE_ID(node) : 0); 789 } 790 791 /************************************************************************ 792 Node name handling 793 ************************************************************************/ 794 795 /* 796 * Assign a node a name. Once assigned, the name cannot be changed. 797 */ 798 int 799 ng_name_node(node_p node, const char *name) 800 { 801 int i; 802 node_p node2; 803 804 /* Check the name is valid */ 805 for (i = 0; i < NG_NODESIZ; i++) { 806 if (name[i] == '\0' || name[i] == '.' || name[i] == ':') 807 break; 808 } 809 if (i == 0 || name[i] != '\0') { 810 TRAP_ERROR(); 811 return (EINVAL); 812 } 813 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */ 814 TRAP_ERROR(); 815 return (EINVAL); 816 } 817 818 /* Check the name isn't already being used */ 819 if ((node2 = ng_name2noderef(node, name)) != NULL) { 820 NG_NODE_UNREF(node2); 821 TRAP_ERROR(); 822 return (EADDRINUSE); 823 } 824 825 /* copy it */ 826 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ); 827 828 return (0); 829 } 830 831 /* 832 * Find a node by absolute name. The name should NOT end with ':' 833 * The name "." means "this node" and "[xxx]" means "the node 834 * with ID (ie, at address) xxx". 835 * 836 * Returns the node if found, else NULL. 837 * Eventually should add something faster than a sequential search. 838 * Note it aquires a reference on the node so you can be sure it's still there. 839 */ 840 node_p 841 ng_name2noderef(node_p here, const char *name) 842 { 843 node_p node; 844 ng_ID_t temp; 845 846 /* "." means "this node" */ 847 if (strcmp(name, ".") == 0) { 848 NG_NODE_REF(here); 849 return(here); 850 } 851 852 /* Check for name-by-ID */ 853 if ((temp = ng_decodeidname(name)) != 0) { 854 return (ng_ID2noderef(temp)); 855 } 856 857 /* Find node by name */ 858 mtx_lock(&ng_nodelist_mtx); 859 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 860 if (NG_NODE_IS_VALID(node) 861 && NG_NODE_HAS_NAME(node) 862 && (strcmp(NG_NODE_NAME(node), name) == 0)) { 863 break; 864 } 865 } 866 if (node) 867 NG_NODE_REF(node); 868 mtx_unlock(&ng_nodelist_mtx); 869 return (node); 870 } 871 872 /* 873 * Decode an ID name, eg. "[f03034de]". Returns 0 if the 874 * string is not valid, otherwise returns the value. 875 */ 876 static ng_ID_t 877 ng_decodeidname(const char *name) 878 { 879 const int len = strlen(name); 880 char *eptr; 881 u_long val; 882 883 /* Check for proper length, brackets, no leading junk */ 884 if ((len < 3) 885 || (name[0] != '[') 886 || (name[len - 1] != ']') 887 || (!isxdigit(name[1]))) { 888 return ((ng_ID_t)0); 889 } 890 891 /* Decode number */ 892 val = strtoul(name + 1, &eptr, 16); 893 if ((eptr - name != len - 1) 894 || (val == ULONG_MAX) 895 || (val == 0)) { 896 return ((ng_ID_t)0); 897 } 898 return (ng_ID_t)val; 899 } 900 901 /* 902 * Remove a name from a node. This should only be called 903 * when shutting down and removing the node. 904 * IF we allow name changing this may be more resurected. 905 */ 906 void 907 ng_unname(node_p node) 908 { 909 } 910 911 /************************************************************************ 912 Hook routines 913 Names are not optional. Hooks are always connected, except for a 914 brief moment within these routines. On invalidation or during creation 915 they are connected to the 'dead' hook. 916 ************************************************************************/ 917 918 /* 919 * Remove a hook reference 920 */ 921 void 922 ng_unref_hook(hook_p hook) 923 { 924 int v; 925 926 if (hook == &ng_deadhook) { 927 return; 928 } 929 do { 930 v = hook->hk_refs; 931 } while (! atomic_cmpset_int(&hook->hk_refs, v, v - 1)); 932 933 if (v == 1) { /* we were the last */ 934 if (_NG_HOOK_NODE(hook)) { /* it'll probably be ng_deadnode */ 935 _NG_NODE_UNREF((_NG_HOOK_NODE(hook))); 936 hook->hk_node = NULL; 937 } 938 NG_FREE_HOOK(hook); 939 } 940 } 941 942 /* 943 * Add an unconnected hook to a node. Only used internally. 944 * Assumes node is locked. (XXX not yet true ) 945 */ 946 static int 947 ng_add_hook(node_p node, const char *name, hook_p *hookp) 948 { 949 hook_p hook; 950 int error = 0; 951 952 /* Check that the given name is good */ 953 if (name == NULL) { 954 TRAP_ERROR(); 955 return (EINVAL); 956 } 957 if (ng_findhook(node, name) != NULL) { 958 TRAP_ERROR(); 959 return (EEXIST); 960 } 961 962 /* Allocate the hook and link it up */ 963 NG_ALLOC_HOOK(hook); 964 if (hook == NULL) { 965 TRAP_ERROR(); 966 return (ENOMEM); 967 } 968 hook->hk_refs = 1; /* add a reference for us to return */ 969 hook->hk_flags = HK_INVALID; 970 hook->hk_peer = &ng_deadhook; /* start off this way */ 971 hook->hk_node = node; 972 NG_NODE_REF(node); /* each hook counts as a reference */ 973 974 /* Set hook name */ 975 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ); 976 977 /* 978 * Check if the node type code has something to say about it 979 * If it fails, the unref of the hook will also unref the node. 980 */ 981 if (node->nd_type->newhook != NULL) { 982 if ((error = (*node->nd_type->newhook)(node, hook, name))) { 983 NG_HOOK_UNREF(hook); /* this frees the hook */ 984 return (error); 985 } 986 } 987 /* 988 * The 'type' agrees so far, so go ahead and link it in. 989 * We'll ask again later when we actually connect the hooks. 990 */ 991 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 992 node->nd_numhooks++; 993 NG_HOOK_REF(hook); /* one for the node */ 994 995 if (hookp) 996 *hookp = hook; 997 return (0); 998 } 999 1000 /* 1001 * Find a hook 1002 * 1003 * Node types may supply their own optimized routines for finding 1004 * hooks. If none is supplied, we just do a linear search. 1005 * XXX Possibly we should add a reference to the hook? 1006 */ 1007 hook_p 1008 ng_findhook(node_p node, const char *name) 1009 { 1010 hook_p hook; 1011 1012 if (node->nd_type->findhook != NULL) 1013 return (*node->nd_type->findhook)(node, name); 1014 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) { 1015 if (NG_HOOK_IS_VALID(hook) 1016 && (strcmp(NG_HOOK_NAME(hook), name) == 0)) 1017 return (hook); 1018 } 1019 return (NULL); 1020 } 1021 1022 /* 1023 * Destroy a hook 1024 * 1025 * As hooks are always attached, this really destroys two hooks. 1026 * The one given, and the one attached to it. Disconnect the hooks 1027 * from each other first. We reconnect the peer hook to the 'dead' 1028 * hook so that it can still exist after we depart. We then 1029 * send the peer its own destroy message. This ensures that we only 1030 * interact with the peer's structures when it is locked processing that 1031 * message. We hold a reference to the peer hook so we are guaranteed that 1032 * the peer hook and node are still going to exist until 1033 * we are finished there as the hook holds a ref on the node. 1034 * We run this same code again on the peer hook, but that time it is already 1035 * attached to the 'dead' hook. 1036 * 1037 * This routine is called at all stages of hook creation 1038 * on error detection and must be able to handle any such stage. 1039 */ 1040 void 1041 ng_destroy_hook(hook_p hook) 1042 { 1043 hook_p peer; 1044 node_p node; 1045 1046 if (hook == &ng_deadhook) { /* better safe than sorry */ 1047 printf("ng_destroy_hook called on deadhook\n"); 1048 return; 1049 } 1050 1051 /* 1052 * Protect divorce process with mutex, to avoid races on 1053 * simultaneous disconnect. 1054 */ 1055 mtx_lock(&ng_topo_mtx); 1056 1057 hook->hk_flags |= HK_INVALID; 1058 1059 peer = NG_HOOK_PEER(hook); 1060 node = NG_HOOK_NODE(hook); 1061 1062 if (peer && (peer != &ng_deadhook)) { 1063 /* 1064 * Set the peer to point to ng_deadhook 1065 * from this moment on we are effectively independent it. 1066 * send it an rmhook message of it's own. 1067 */ 1068 peer->hk_peer = &ng_deadhook; /* They no longer know us */ 1069 hook->hk_peer = &ng_deadhook; /* Nor us, them */ 1070 if (NG_HOOK_NODE(peer) == &ng_deadnode) { 1071 /* 1072 * If it's already divorced from a node, 1073 * just free it. 1074 */ 1075 mtx_unlock(&ng_topo_mtx); 1076 } else { 1077 mtx_unlock(&ng_topo_mtx); 1078 ng_rmhook_self(peer); /* Send it a surprise */ 1079 } 1080 NG_HOOK_UNREF(peer); /* account for peer link */ 1081 NG_HOOK_UNREF(hook); /* account for peer link */ 1082 } else 1083 mtx_unlock(&ng_topo_mtx); 1084 1085 mtx_assert(&ng_topo_mtx, MA_NOTOWNED); 1086 1087 /* 1088 * Remove the hook from the node's list to avoid possible recursion 1089 * in case the disconnection results in node shutdown. 1090 */ 1091 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */ 1092 return; 1093 } 1094 LIST_REMOVE(hook, hk_hooks); 1095 node->nd_numhooks--; 1096 if (node->nd_type->disconnect) { 1097 /* 1098 * The type handler may elect to destroy the node so don't 1099 * trust its existance after this point. (except 1100 * that we still hold a reference on it. (which we 1101 * inherrited from the hook we are destroying) 1102 */ 1103 (*node->nd_type->disconnect) (hook); 1104 } 1105 1106 /* 1107 * Note that because we will point to ng_deadnode, the original node 1108 * is not decremented automatically so we do that manually. 1109 */ 1110 _NG_HOOK_NODE(hook) = &ng_deadnode; 1111 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */ 1112 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */ 1113 } 1114 1115 /* 1116 * Take two hooks on a node and merge the connection so that the given node 1117 * is effectively bypassed. 1118 */ 1119 int 1120 ng_bypass(hook_p hook1, hook_p hook2) 1121 { 1122 if (hook1->hk_node != hook2->hk_node) { 1123 TRAP_ERROR(); 1124 return (EINVAL); 1125 } 1126 hook1->hk_peer->hk_peer = hook2->hk_peer; 1127 hook2->hk_peer->hk_peer = hook1->hk_peer; 1128 1129 hook1->hk_peer = &ng_deadhook; 1130 hook2->hk_peer = &ng_deadhook; 1131 1132 /* XXX If we ever cache methods on hooks update them as well */ 1133 ng_destroy_hook(hook1); 1134 ng_destroy_hook(hook2); 1135 return (0); 1136 } 1137 1138 /* 1139 * Install a new netgraph type 1140 */ 1141 int 1142 ng_newtype(struct ng_type *tp) 1143 { 1144 const size_t namelen = strlen(tp->name); 1145 1146 /* Check version and type name fields */ 1147 if ((tp->version != NG_ABI_VERSION) 1148 || (namelen == 0) 1149 || (namelen >= NG_TYPESIZ)) { 1150 TRAP_ERROR(); 1151 if (tp->version != NG_ABI_VERSION) { 1152 printf("Netgraph: Node type rejected. ABI mismatch. Suggest recompile\n"); 1153 } 1154 return (EINVAL); 1155 } 1156 1157 /* Check for name collision */ 1158 if (ng_findtype(tp->name) != NULL) { 1159 TRAP_ERROR(); 1160 return (EEXIST); 1161 } 1162 1163 1164 /* Link in new type */ 1165 mtx_lock(&ng_typelist_mtx); 1166 LIST_INSERT_HEAD(&ng_typelist, tp, types); 1167 tp->refs = 1; /* first ref is linked list */ 1168 mtx_unlock(&ng_typelist_mtx); 1169 return (0); 1170 } 1171 1172 /* 1173 * unlink a netgraph type 1174 * If no examples exist 1175 */ 1176 int 1177 ng_rmtype(struct ng_type *tp) 1178 { 1179 /* Check for name collision */ 1180 if (tp->refs != 1) { 1181 TRAP_ERROR(); 1182 return (EBUSY); 1183 } 1184 1185 /* Unlink type */ 1186 mtx_lock(&ng_typelist_mtx); 1187 LIST_REMOVE(tp, types); 1188 mtx_unlock(&ng_typelist_mtx); 1189 return (0); 1190 } 1191 1192 /* 1193 * Look for a type of the name given 1194 */ 1195 struct ng_type * 1196 ng_findtype(const char *typename) 1197 { 1198 struct ng_type *type; 1199 1200 mtx_lock(&ng_typelist_mtx); 1201 LIST_FOREACH(type, &ng_typelist, types) { 1202 if (strcmp(type->name, typename) == 0) 1203 break; 1204 } 1205 mtx_unlock(&ng_typelist_mtx); 1206 return (type); 1207 } 1208 1209 /************************************************************************ 1210 Composite routines 1211 ************************************************************************/ 1212 /* 1213 * Connect two nodes using the specified hooks, using queued functions. 1214 */ 1215 static void 1216 ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2) 1217 { 1218 1219 /* 1220 * When we run, we know that the node 'node' is locked for us. 1221 * Our caller has a reference on the hook. 1222 * Our caller has a reference on the node. 1223 * (In this case our caller is ng_apply_item() ). 1224 * The peer hook has a reference on the hook. 1225 * We are all set up except for the final call to the node, and 1226 * the clearing of the INVALID flag. 1227 */ 1228 if (NG_HOOK_NODE(hook) == &ng_deadnode) { 1229 /* 1230 * The node must have been freed again since we last visited 1231 * here. ng_destry_hook() has this effect but nothing else does. 1232 * We should just release our references and 1233 * free anything we can think of. 1234 * Since we know it's been destroyed, and it's our caller 1235 * that holds the references, just return. 1236 */ 1237 return ; 1238 } 1239 if (hook->hk_node->nd_type->connect) { 1240 if ((*hook->hk_node->nd_type->connect) (hook)) { 1241 ng_destroy_hook(hook); /* also zaps peer */ 1242 printf("failed in ng_con_part3()\n"); 1243 return ; 1244 } 1245 } 1246 /* 1247 * XXX this is wrong for SMP. Possibly we need 1248 * to separate out 'create' and 'invalid' flags. 1249 * should only set flags on hooks we have locked under our node. 1250 */ 1251 hook->hk_flags &= ~HK_INVALID; 1252 return ; 1253 } 1254 1255 static void 1256 ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2) 1257 { 1258 hook_p peer; 1259 1260 /* 1261 * When we run, we know that the node 'node' is locked for us. 1262 * Our caller has a reference on the hook. 1263 * Our caller has a reference on the node. 1264 * (In this case our caller is ng_apply_item() ). 1265 * The peer hook has a reference on the hook. 1266 * our node pointer points to the 'dead' node. 1267 * First check the hook name is unique. 1268 * Should not happen because we checked before queueing this. 1269 */ 1270 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) { 1271 TRAP_ERROR(); 1272 ng_destroy_hook(hook); /* should destroy peer too */ 1273 printf("failed in ng_con_part2()\n"); 1274 return ; 1275 } 1276 /* 1277 * Check if the node type code has something to say about it 1278 * If it fails, the unref of the hook will also unref the attached node, 1279 * however since that node is 'ng_deadnode' this will do nothing. 1280 * The peer hook will also be destroyed. 1281 */ 1282 if (node->nd_type->newhook != NULL) { 1283 if ((*node->nd_type->newhook)(node, hook, hook->hk_name)) { 1284 ng_destroy_hook(hook); /* should destroy peer too */ 1285 printf("failed in ng_con_part2()\n"); 1286 return ; 1287 } 1288 } 1289 1290 /* 1291 * The 'type' agrees so far, so go ahead and link it in. 1292 * We'll ask again later when we actually connect the hooks. 1293 */ 1294 hook->hk_node = node; /* just overwrite ng_deadnode */ 1295 NG_NODE_REF(node); /* each hook counts as a reference */ 1296 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1297 node->nd_numhooks++; 1298 NG_HOOK_REF(hook); /* one for the node */ 1299 1300 /* 1301 * We now have a symetrical situation, where both hooks have been 1302 * linked to their nodes, the newhook methods have been called 1303 * And the references are all correct. The hooks are still marked 1304 * as invalid, as we have not called the 'connect' methods 1305 * yet. 1306 * We can call the local one immediatly as we have the 1307 * node locked, but we need to queue the remote one. 1308 */ 1309 if (hook->hk_node->nd_type->connect) { 1310 if ((*hook->hk_node->nd_type->connect) (hook)) { 1311 ng_destroy_hook(hook); /* also zaps peer */ 1312 printf("failed in ng_con_part2(A)\n"); 1313 return ; 1314 } 1315 } 1316 1317 /* 1318 * Acquire topo mutex to avoid race with ng_destroy_hook(). 1319 */ 1320 mtx_lock(&ng_topo_mtx); 1321 peer = hook->hk_peer; 1322 if (peer == &ng_deadhook) { 1323 mtx_unlock(&ng_topo_mtx); 1324 printf("failed in ng_con_part2(B)\n"); 1325 ng_destroy_hook(hook); 1326 return ; 1327 } 1328 mtx_unlock(&ng_topo_mtx); 1329 1330 if (ng_send_fn(peer->hk_node, peer, &ng_con_part3, arg1, arg2)) { 1331 printf("failed in ng_con_part2(C)\n"); 1332 ng_destroy_hook(hook); /* also zaps peer */ 1333 return ; 1334 } 1335 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */ 1336 return ; 1337 } 1338 1339 /* 1340 * Connect this node with another node. We assume that this node is 1341 * currently locked, as we are only called from an NGM_CONNECT message. 1342 */ 1343 static int 1344 ng_con_nodes(node_p node, const char *name, node_p node2, const char *name2) 1345 { 1346 int error; 1347 hook_p hook; 1348 hook_p hook2; 1349 1350 if (ng_findhook(node2, name2) != NULL) { 1351 return(EEXIST); 1352 } 1353 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */ 1354 return (error); 1355 /* Allocate the other hook and link it up */ 1356 NG_ALLOC_HOOK(hook2); 1357 if (hook2 == NULL) { 1358 TRAP_ERROR(); 1359 ng_destroy_hook(hook); /* XXX check ref counts so far */ 1360 NG_HOOK_UNREF(hook); /* including our ref */ 1361 return (ENOMEM); 1362 } 1363 hook2->hk_refs = 1; /* start with a reference for us. */ 1364 hook2->hk_flags = HK_INVALID; 1365 hook2->hk_peer = hook; /* Link the two together */ 1366 hook->hk_peer = hook2; 1367 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/ 1368 NG_HOOK_REF(hook2); 1369 hook2->hk_node = &ng_deadnode; 1370 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ); 1371 1372 /* 1373 * Queue the function above. 1374 * Procesing continues in that function in the lock context of 1375 * the other node. 1376 */ 1377 ng_send_fn(node2, hook2, &ng_con_part2, NULL, 0); 1378 1379 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */ 1380 NG_HOOK_UNREF(hook2); 1381 return (0); 1382 } 1383 1384 /* 1385 * Make a peer and connect. 1386 * We assume that the local node is locked. 1387 * The new node probably doesn't need a lock until 1388 * it has a hook, because it cannot really have any work until then, 1389 * but we should think about it a bit more. 1390 * 1391 * The problem may come if the other node also fires up 1392 * some hardware or a timer or some other source of activation, 1393 * also it may already get a command msg via it's ID. 1394 * 1395 * We could use the same method as ng_con_nodes() but we'd have 1396 * to add ability to remove the node when failing. (Not hard, just 1397 * make arg1 point to the node to remove). 1398 * Unless of course we just ignore failure to connect and leave 1399 * an unconnected node? 1400 */ 1401 static int 1402 ng_mkpeer(node_p node, const char *name, const char *name2, char *type) 1403 { 1404 node_p node2; 1405 hook_p hook1, hook2; 1406 int error; 1407 1408 if ((error = ng_make_node(type, &node2))) { 1409 return (error); 1410 } 1411 1412 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */ 1413 ng_rmnode(node2, NULL, NULL, 0); 1414 return (error); 1415 } 1416 1417 if ((error = ng_add_hook(node2, name2, &hook2))) { 1418 ng_rmnode(node2, NULL, NULL, 0); 1419 ng_destroy_hook(hook1); 1420 NG_HOOK_UNREF(hook1); 1421 return (error); 1422 } 1423 1424 /* 1425 * Actually link the two hooks together. 1426 */ 1427 hook1->hk_peer = hook2; 1428 hook2->hk_peer = hook1; 1429 1430 /* Each hook is referenced by the other */ 1431 NG_HOOK_REF(hook1); 1432 NG_HOOK_REF(hook2); 1433 1434 /* Give each node the opportunity to veto the pending connection */ 1435 if (hook1->hk_node->nd_type->connect) { 1436 error = (*hook1->hk_node->nd_type->connect) (hook1); 1437 } 1438 1439 if ((error == 0) && hook2->hk_node->nd_type->connect) { 1440 error = (*hook2->hk_node->nd_type->connect) (hook2); 1441 1442 } 1443 1444 /* 1445 * drop the references we were holding on the two hooks. 1446 */ 1447 if (error) { 1448 ng_destroy_hook(hook2); /* also zaps hook1 */ 1449 ng_rmnode(node2, NULL, NULL, 0); 1450 } else { 1451 /* As a last act, allow the hooks to be used */ 1452 hook1->hk_flags &= ~HK_INVALID; 1453 hook2->hk_flags &= ~HK_INVALID; 1454 } 1455 NG_HOOK_UNREF(hook1); 1456 NG_HOOK_UNREF(hook2); 1457 return (error); 1458 } 1459 1460 /************************************************************************ 1461 Utility routines to send self messages 1462 ************************************************************************/ 1463 1464 /* Shut this node down as soon as everyone is clear of it */ 1465 /* Should add arg "immediatly" to jump the queue */ 1466 int 1467 ng_rmnode_self(node_p node) 1468 { 1469 int error; 1470 1471 if (node == &ng_deadnode) 1472 return (0); 1473 node->nd_flags |= NGF_INVALID; 1474 if (node->nd_flags & NGF_CLOSING) 1475 return (0); 1476 1477 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0); 1478 return (error); 1479 } 1480 1481 static void 1482 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2) 1483 { 1484 ng_destroy_hook(hook); 1485 return ; 1486 } 1487 1488 int 1489 ng_rmhook_self(hook_p hook) 1490 { 1491 int error; 1492 node_p node = NG_HOOK_NODE(hook); 1493 1494 if (node == &ng_deadnode) 1495 return (0); 1496 1497 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0); 1498 return (error); 1499 } 1500 1501 /*********************************************************************** 1502 * Parse and verify a string of the form: <NODE:><PATH> 1503 * 1504 * Such a string can refer to a specific node or a specific hook 1505 * on a specific node, depending on how you look at it. In the 1506 * latter case, the PATH component must not end in a dot. 1507 * 1508 * Both <NODE:> and <PATH> are optional. The <PATH> is a string 1509 * of hook names separated by dots. This breaks out the original 1510 * string, setting *nodep to "NODE" (or NULL if none) and *pathp 1511 * to "PATH" (or NULL if degenerate). Also, *hookp will point to 1512 * the final hook component of <PATH>, if any, otherwise NULL. 1513 * 1514 * This returns -1 if the path is malformed. The char ** are optional. 1515 ***********************************************************************/ 1516 int 1517 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp) 1518 { 1519 char *node, *path, *hook; 1520 int k; 1521 1522 /* 1523 * Extract absolute NODE, if any 1524 */ 1525 for (path = addr; *path && *path != ':'; path++); 1526 if (*path) { 1527 node = addr; /* Here's the NODE */ 1528 *path++ = '\0'; /* Here's the PATH */ 1529 1530 /* Node name must not be empty */ 1531 if (!*node) 1532 return -1; 1533 1534 /* A name of "." is OK; otherwise '.' not allowed */ 1535 if (strcmp(node, ".") != 0) { 1536 for (k = 0; node[k]; k++) 1537 if (node[k] == '.') 1538 return -1; 1539 } 1540 } else { 1541 node = NULL; /* No absolute NODE */ 1542 path = addr; /* Here's the PATH */ 1543 } 1544 1545 /* Snoop for illegal characters in PATH */ 1546 for (k = 0; path[k]; k++) 1547 if (path[k] == ':') 1548 return -1; 1549 1550 /* Check for no repeated dots in PATH */ 1551 for (k = 0; path[k]; k++) 1552 if (path[k] == '.' && path[k + 1] == '.') 1553 return -1; 1554 1555 /* Remove extra (degenerate) dots from beginning or end of PATH */ 1556 if (path[0] == '.') 1557 path++; 1558 if (*path && path[strlen(path) - 1] == '.') 1559 path[strlen(path) - 1] = 0; 1560 1561 /* If PATH has a dot, then we're not talking about a hook */ 1562 if (*path) { 1563 for (hook = path, k = 0; path[k]; k++) 1564 if (path[k] == '.') { 1565 hook = NULL; 1566 break; 1567 } 1568 } else 1569 path = hook = NULL; 1570 1571 /* Done */ 1572 if (nodep) 1573 *nodep = node; 1574 if (pathp) 1575 *pathp = path; 1576 if (hookp) 1577 *hookp = hook; 1578 return (0); 1579 } 1580 1581 /* 1582 * Given a path, which may be absolute or relative, and a starting node, 1583 * return the destination node. 1584 */ 1585 int 1586 ng_path2noderef(node_p here, const char *address, 1587 node_p *destp, hook_p *lasthook) 1588 { 1589 char fullpath[NG_PATHSIZ]; 1590 char *nodename, *path, pbuf[2]; 1591 node_p node, oldnode; 1592 char *cp; 1593 hook_p hook = NULL; 1594 1595 /* Initialize */ 1596 if (destp == NULL) { 1597 TRAP_ERROR(); 1598 return EINVAL; 1599 } 1600 *destp = NULL; 1601 1602 /* Make a writable copy of address for ng_path_parse() */ 1603 strncpy(fullpath, address, sizeof(fullpath) - 1); 1604 fullpath[sizeof(fullpath) - 1] = '\0'; 1605 1606 /* Parse out node and sequence of hooks */ 1607 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) { 1608 TRAP_ERROR(); 1609 return EINVAL; 1610 } 1611 if (path == NULL) { 1612 pbuf[0] = '.'; /* Needs to be writable */ 1613 pbuf[1] = '\0'; 1614 path = pbuf; 1615 } 1616 1617 /* 1618 * For an absolute address, jump to the starting node. 1619 * Note that this holds a reference on the node for us. 1620 * Don't forget to drop the reference if we don't need it. 1621 */ 1622 if (nodename) { 1623 node = ng_name2noderef(here, nodename); 1624 if (node == NULL) { 1625 TRAP_ERROR(); 1626 return (ENOENT); 1627 } 1628 } else { 1629 if (here == NULL) { 1630 TRAP_ERROR(); 1631 return (EINVAL); 1632 } 1633 node = here; 1634 NG_NODE_REF(node); 1635 } 1636 1637 /* 1638 * Now follow the sequence of hooks 1639 * XXX 1640 * We actually cannot guarantee that the sequence 1641 * is not being demolished as we crawl along it 1642 * without extra-ordinary locking etc. 1643 * So this is a bit dodgy to say the least. 1644 * We can probably hold up some things by holding 1645 * the nodelist mutex for the time of this 1646 * crawl if we wanted.. At least that way we wouldn't have to 1647 * worry about the nodes dissappearing, but the hooks would still 1648 * be a problem. 1649 */ 1650 for (cp = path; node != NULL && *cp != '\0'; ) { 1651 char *segment; 1652 1653 /* 1654 * Break out the next path segment. Replace the dot we just 1655 * found with a NUL; "cp" points to the next segment (or the 1656 * NUL at the end). 1657 */ 1658 for (segment = cp; *cp != '\0'; cp++) { 1659 if (*cp == '.') { 1660 *cp++ = '\0'; 1661 break; 1662 } 1663 } 1664 1665 /* Empty segment */ 1666 if (*segment == '\0') 1667 continue; 1668 1669 /* We have a segment, so look for a hook by that name */ 1670 hook = ng_findhook(node, segment); 1671 1672 /* Can't get there from here... */ 1673 if (hook == NULL 1674 || NG_HOOK_PEER(hook) == NULL 1675 || NG_HOOK_NOT_VALID(hook) 1676 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) { 1677 TRAP_ERROR(); 1678 NG_NODE_UNREF(node); 1679 #if 0 1680 printf("hooknotvalid %s %s %d %d %d %d ", 1681 path, 1682 segment, 1683 hook == NULL, 1684 NG_HOOK_PEER(hook) == NULL, 1685 NG_HOOK_NOT_VALID(hook), 1686 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))); 1687 #endif 1688 return (ENOENT); 1689 } 1690 1691 /* 1692 * Hop on over to the next node 1693 * XXX 1694 * Big race conditions here as hooks and nodes go away 1695 * *** Idea.. store an ng_ID_t in each hook and use that 1696 * instead of the direct hook in this crawl? 1697 */ 1698 oldnode = node; 1699 if ((node = NG_PEER_NODE(hook))) 1700 NG_NODE_REF(node); /* XXX RACE */ 1701 NG_NODE_UNREF(oldnode); /* XXX another race */ 1702 if (NG_NODE_NOT_VALID(node)) { 1703 NG_NODE_UNREF(node); /* XXX more races */ 1704 node = NULL; 1705 } 1706 } 1707 1708 /* If node somehow missing, fail here (probably this is not needed) */ 1709 if (node == NULL) { 1710 TRAP_ERROR(); 1711 return (ENXIO); 1712 } 1713 1714 /* Done */ 1715 *destp = node; 1716 if (lasthook != NULL) 1717 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL); 1718 return (0); 1719 } 1720 1721 /***************************************************************\ 1722 * Input queue handling. 1723 * All activities are submitted to the node via the input queue 1724 * which implements a multiple-reader/single-writer gate. 1725 * Items which cannot be handled immeditly are queued. 1726 * 1727 * read-write queue locking inline functions * 1728 \***************************************************************/ 1729 1730 static __inline item_p ng_dequeue(struct ng_queue * ngq, int *rw); 1731 static __inline item_p ng_acquire_read(struct ng_queue * ngq, 1732 item_p item); 1733 static __inline item_p ng_acquire_write(struct ng_queue * ngq, 1734 item_p item); 1735 static __inline void ng_leave_read(struct ng_queue * ngq); 1736 static __inline void ng_leave_write(struct ng_queue * ngq); 1737 static __inline void ng_queue_rw(struct ng_queue * ngq, 1738 item_p item, int rw); 1739 1740 /* 1741 * Definition of the bits fields in the ng_queue flag word. 1742 * Defined here rather than in netgraph.h because no-one should fiddle 1743 * with them. 1744 * 1745 * The ordering here may be important! don't shuffle these. 1746 */ 1747 /*- 1748 Safety Barrier--------+ (adjustable to suit taste) (not used yet) 1749 | 1750 V 1751 +-------+-------+-------+-------+-------+-------+-------+-------+ 1752 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1753 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |P|A| 1754 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |O|W| 1755 +-------+-------+-------+-------+-------+-------+-------+-------+ 1756 \___________________________ ____________________________/ | | 1757 V | | 1758 [active reader count] | | 1759 | | 1760 Operation Pending -------------------------------+ | 1761 | 1762 Active Writer ---------------------------------------+ 1763 1764 1765 */ 1766 #define WRITER_ACTIVE 0x00000001 1767 #define OP_PENDING 0x00000002 1768 #define READER_INCREMENT 0x00000004 1769 #define READER_MASK 0xfffffffc /* Not valid if WRITER_ACTIVE is set */ 1770 #define SAFETY_BARRIER 0x00100000 /* 128K items queued should be enough */ 1771 1772 /* Defines of more elaborate states on the queue */ 1773 /* Mask of bits a new read cares about */ 1774 #define NGQ_RMASK (WRITER_ACTIVE|OP_PENDING) 1775 1776 /* Mask of bits a new write cares about */ 1777 #define NGQ_WMASK (NGQ_RMASK|READER_MASK) 1778 1779 /* Test to decide if there is something on the queue. */ 1780 #define QUEUE_ACTIVE(QP) ((QP)->q_flags & OP_PENDING) 1781 1782 /* How to decide what the next queued item is. */ 1783 #define HEAD_IS_READER(QP) NGI_QUEUED_READER((QP)->queue) 1784 #define HEAD_IS_WRITER(QP) NGI_QUEUED_WRITER((QP)->queue) /* notused */ 1785 1786 /* Read the status to decide if the next item on the queue can now run. */ 1787 #define QUEUED_READER_CAN_PROCEED(QP) \ 1788 (((QP)->q_flags & (NGQ_RMASK & ~OP_PENDING)) == 0) 1789 #define QUEUED_WRITER_CAN_PROCEED(QP) \ 1790 (((QP)->q_flags & (NGQ_WMASK & ~OP_PENDING)) == 0) 1791 1792 /* Is there a chance of getting ANY work off the queue? */ 1793 #define NEXT_QUEUED_ITEM_CAN_PROCEED(QP) \ 1794 (QUEUE_ACTIVE(QP) && \ 1795 ((HEAD_IS_READER(QP)) ? QUEUED_READER_CAN_PROCEED(QP) : \ 1796 QUEUED_WRITER_CAN_PROCEED(QP))) 1797 1798 1799 #define NGQRW_R 0 1800 #define NGQRW_W 1 1801 1802 /* 1803 * Taking into account the current state of the queue and node, possibly take 1804 * the next entry off the queue and return it. Return NULL if there was 1805 * nothing we could return, either because there really was nothing there, or 1806 * because the node was in a state where it cannot yet process the next item 1807 * on the queue. 1808 * 1809 * This MUST MUST MUST be called with the mutex held. 1810 */ 1811 static __inline item_p 1812 ng_dequeue(struct ng_queue *ngq, int *rw) 1813 { 1814 item_p item; 1815 u_int add_arg; 1816 1817 mtx_assert(&ngq->q_mtx, MA_OWNED); 1818 /* 1819 * If there is nothing queued, then just return. 1820 * No point in continuing. 1821 * XXXGL: assert this? 1822 */ 1823 if (!QUEUE_ACTIVE(ngq)) { 1824 CTR4(KTR_NET, "%20s: node [%x] (%p) queue empty; " 1825 "queue flags 0x%lx", __func__, 1826 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1827 return (NULL); 1828 } 1829 1830 /* 1831 * From here, we can assume there is a head item. 1832 * We need to find out what it is and if it can be dequeued, given 1833 * the current state of the node. 1834 */ 1835 if (HEAD_IS_READER(ngq)) { 1836 if (!QUEUED_READER_CAN_PROCEED(ngq)) { 1837 /* 1838 * It's a reader but we can't use it. 1839 * We are stalled so make sure we don't 1840 * get called again until something changes. 1841 */ 1842 ng_worklist_remove(ngq->q_node); 1843 CTR4(KTR_NET, "%20s: node [%x] (%p) queued reader " 1844 "can't proceed; queue flags 0x%lx", __func__, 1845 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1846 return (NULL); 1847 } 1848 /* 1849 * Head of queue is a reader and we have no write active. 1850 * We don't care how many readers are already active. 1851 * Add the correct increment for the reader count. 1852 */ 1853 add_arg = READER_INCREMENT; 1854 *rw = NGQRW_R; 1855 } else if (QUEUED_WRITER_CAN_PROCEED(ngq)) { 1856 /* 1857 * There is a pending write, no readers and no active writer. 1858 * This means we can go ahead with the pending writer. Note 1859 * the fact that we now have a writer, ready for when we take 1860 * it off the queue. 1861 * 1862 * We don't need to worry about a possible collision with the 1863 * fasttrack reader. 1864 * 1865 * The fasttrack thread may take a long time to discover that we 1866 * are running so we would have an inconsistent state in the 1867 * flags for a while. Since we ignore the reader count 1868 * entirely when the WRITER_ACTIVE flag is set, this should 1869 * not matter (in fact it is defined that way). If it tests 1870 * the flag before this operation, the OP_PENDING flag 1871 * will make it fail, and if it tests it later, the 1872 * WRITER_ACTIVE flag will do the same. If it is SO slow that 1873 * we have actually completed the operation, and neither flag 1874 * is set by the time that it tests the flags, then it is 1875 * actually ok for it to continue. If it completes and we've 1876 * finished and the read pending is set it still fails. 1877 * 1878 * So we can just ignore it, as long as we can ensure that the 1879 * transition from WRITE_PENDING state to the WRITER_ACTIVE 1880 * state is atomic. 1881 * 1882 * After failing, first it will be held back by the mutex, then 1883 * when it can proceed, it will queue its request, then it 1884 * would arrive at this function. Usually it will have to 1885 * leave empty handed because the ACTIVE WRITER bit will be 1886 * set. 1887 * 1888 * Adjust the flags for the new active writer. 1889 */ 1890 add_arg = WRITER_ACTIVE; 1891 *rw = NGQRW_W; 1892 /* 1893 * We want to write "active writer, no readers " Now go make 1894 * it true. In fact there may be a number in the readers 1895 * count but we know it is not true and will be fixed soon. 1896 * We will fix the flags for the next pending entry in a 1897 * moment. 1898 */ 1899 } else { 1900 /* 1901 * We can't dequeue anything.. return and say so. Probably we 1902 * have a write pending and the readers count is non zero. If 1903 * we got here because a reader hit us just at the wrong 1904 * moment with the fasttrack code, and put us in a strange 1905 * state, then it will be coming through in just a moment, 1906 * (just as soon as we release the mutex) and keep things 1907 * moving. 1908 * Make sure we remove ourselves from the work queue. It 1909 * would be a waste of effort to do all this again. 1910 */ 1911 ng_worklist_remove(ngq->q_node); 1912 CTR4(KTR_NET, "%20s: node [%x] (%p) can't dequeue anything; " 1913 "queue flags 0x%lx", __func__, 1914 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1915 return (NULL); 1916 } 1917 1918 /* 1919 * Now we dequeue the request (whatever it may be) and correct the 1920 * pending flags and the next and last pointers. 1921 */ 1922 item = ngq->queue; 1923 ngq->queue = item->el_next; 1924 CTR6(KTR_NET, "%20s: node [%x] (%p) dequeued item %p with flags 0x%lx; " 1925 "queue flags 0x%lx", __func__, 1926 ngq->q_node->nd_ID,ngq->q_node, item, item->el_flags, ngq->q_flags); 1927 if (ngq->last == &(item->el_next)) { 1928 /* 1929 * that was the last entry in the queue so set the 'last 1930 * pointer up correctly and make sure the pending flag is 1931 * clear. 1932 */ 1933 add_arg += -OP_PENDING; 1934 ngq->last = &(ngq->queue); 1935 /* 1936 * Whatever flag was set will be cleared and 1937 * the new acive field will be set by the add as well, 1938 * so we don't need to change add_arg. 1939 * But we know we don't need to be on the work list. 1940 */ 1941 atomic_add_long(&ngq->q_flags, add_arg); 1942 ng_worklist_remove(ngq->q_node); 1943 } else { 1944 /* 1945 * Since there is still something on the queue 1946 * we don't need to change the PENDING flag. 1947 */ 1948 atomic_add_long(&ngq->q_flags, add_arg); 1949 /* 1950 * If we see more doable work, make sure we are 1951 * on the work queue. 1952 */ 1953 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) { 1954 ng_setisr(ngq->q_node); 1955 } 1956 } 1957 CTR6(KTR_NET, "%20s: node [%x] (%p) returning item %p as %s; " 1958 "queue flags 0x%lx", __func__, 1959 ngq->q_node->nd_ID, ngq->q_node, item, *rw ? "WRITER" : "READER" , 1960 ngq->q_flags); 1961 return (item); 1962 } 1963 1964 /* 1965 * Queue a packet to be picked up by someone else. 1966 * We really don't care who, but we can't or don't want to hang around 1967 * to process it ourselves. We are probably an interrupt routine.. 1968 * If the queue could be run, flag the netisr handler to start. 1969 */ 1970 static __inline void 1971 ng_queue_rw(struct ng_queue * ngq, item_p item, int rw) 1972 { 1973 mtx_assert(&ngq->q_mtx, MA_OWNED); 1974 1975 if (rw == NGQRW_W) 1976 NGI_SET_WRITER(item); 1977 else 1978 NGI_SET_READER(item); 1979 item->el_next = NULL; /* maybe not needed */ 1980 *ngq->last = item; 1981 CTR5(KTR_NET, "%20s: node [%x] (%p) queued item %p as %s", __func__, 1982 ngq->q_node->nd_ID, ngq->q_node, item, rw ? "WRITER" : "READER" ); 1983 /* 1984 * If it was the first item in the queue then we need to 1985 * set the last pointer and the type flags. 1986 */ 1987 if (ngq->last == &(ngq->queue)) { 1988 atomic_add_long(&ngq->q_flags, OP_PENDING); 1989 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__, 1990 ngq->q_node->nd_ID, ngq->q_node); 1991 } 1992 1993 ngq->last = &(item->el_next); 1994 /* 1995 * We can take the worklist lock with the node locked 1996 * BUT NOT THE REVERSE! 1997 */ 1998 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 1999 ng_setisr(ngq->q_node); 2000 } 2001 2002 2003 /* 2004 * This function 'cheats' in that it first tries to 'grab' the use of the 2005 * node, without going through the mutex. We can do this becasue of the 2006 * semantics of the lock. The semantics include a clause that says that the 2007 * value of the readers count is invalid if the WRITER_ACTIVE flag is set. It 2008 * also says that the WRITER_ACTIVE flag cannot be set if the readers count 2009 * is not zero. Note that this talks about what is valid to SET the 2010 * WRITER_ACTIVE flag, because from the moment it is set, the value if the 2011 * reader count is immaterial, and not valid. The two 'pending' flags have a 2012 * similar effect, in that If they are orthogonal to the two active fields in 2013 * how they are set, but if either is set, the attempted 'grab' need to be 2014 * backed out because there is earlier work, and we maintain ordering in the 2015 * queue. The result of this is that the reader request can try obtain use of 2016 * the node with only a single atomic addition, and without any of the mutex 2017 * overhead. If this fails the operation degenerates to the same as for other 2018 * cases. 2019 * 2020 */ 2021 static __inline item_p 2022 ng_acquire_read(struct ng_queue *ngq, item_p item) 2023 { 2024 KASSERT(ngq != &ng_deadnode.nd_input_queue, 2025 ("%s: working on deadnode", __func__)); 2026 2027 /* ######### Hack alert ######### */ 2028 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 2029 if ((ngq->q_flags & NGQ_RMASK) == 0) { 2030 /* Successfully grabbed node */ 2031 CTR4(KTR_NET, "%20s: node [%x] (%p) fast acquired item %p", 2032 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2033 return (item); 2034 } 2035 /* undo the damage if we didn't succeed */ 2036 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 2037 2038 /* ######### End Hack alert ######### */ 2039 mtx_lock_spin((&ngq->q_mtx)); 2040 /* 2041 * Try again. Another processor (or interrupt for that matter) may 2042 * have removed the last queued item that was stopping us from 2043 * running, between the previous test, and the moment that we took 2044 * the mutex. (Or maybe a writer completed.) 2045 * Even if another fast-track reader hits during this period 2046 * we don't care as multiple readers is OK. 2047 */ 2048 if ((ngq->q_flags & NGQ_RMASK) == 0) { 2049 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 2050 mtx_unlock_spin((&ngq->q_mtx)); 2051 CTR4(KTR_NET, "%20s: node [%x] (%p) slow acquired item %p", 2052 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2053 return (item); 2054 } 2055 2056 /* 2057 * and queue the request for later. 2058 */ 2059 ng_queue_rw(ngq, item, NGQRW_R); 2060 mtx_unlock_spin(&(ngq->q_mtx)); 2061 2062 return (NULL); 2063 } 2064 2065 static __inline item_p 2066 ng_acquire_write(struct ng_queue *ngq, item_p item) 2067 { 2068 KASSERT(ngq != &ng_deadnode.nd_input_queue, 2069 ("%s: working on deadnode", __func__)); 2070 2071 restart: 2072 mtx_lock_spin(&(ngq->q_mtx)); 2073 /* 2074 * If there are no readers, no writer, and no pending packets, then 2075 * we can just go ahead. In all other situations we need to queue the 2076 * request 2077 */ 2078 if ((ngq->q_flags & NGQ_WMASK) == 0) { 2079 /* collision could happen *HERE* */ 2080 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE); 2081 mtx_unlock_spin((&ngq->q_mtx)); 2082 if (ngq->q_flags & READER_MASK) { 2083 /* Collision with fast-track reader */ 2084 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2085 goto restart; 2086 } 2087 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p", 2088 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2089 return (item); 2090 } 2091 2092 /* 2093 * and queue the request for later. 2094 */ 2095 ng_queue_rw(ngq, item, NGQRW_W); 2096 mtx_unlock_spin(&(ngq->q_mtx)); 2097 2098 return (NULL); 2099 } 2100 2101 static __inline void 2102 ng_leave_read(struct ng_queue *ngq) 2103 { 2104 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 2105 } 2106 2107 static __inline void 2108 ng_leave_write(struct ng_queue *ngq) 2109 { 2110 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2111 } 2112 2113 static void 2114 ng_flush_input_queue(struct ng_queue * ngq) 2115 { 2116 item_p item; 2117 2118 mtx_lock_spin(&ngq->q_mtx); 2119 while (ngq->queue) { 2120 item = ngq->queue; 2121 ngq->queue = item->el_next; 2122 if (ngq->last == &(item->el_next)) { 2123 ngq->last = &(ngq->queue); 2124 atomic_add_long(&ngq->q_flags, -OP_PENDING); 2125 } 2126 mtx_unlock_spin(&ngq->q_mtx); 2127 /* If the item is supplying a callback, call it with an error */ 2128 if (item->apply != NULL) { 2129 (item->apply)(item->context, ENOENT); 2130 item->apply = NULL; 2131 } 2132 NG_FREE_ITEM(item); 2133 mtx_lock_spin(&ngq->q_mtx); 2134 } 2135 /* 2136 * Take us off the work queue if we are there. 2137 * We definatly have no work to be done. 2138 */ 2139 ng_worklist_remove(ngq->q_node); 2140 mtx_unlock_spin(&ngq->q_mtx); 2141 } 2142 2143 /*********************************************************************** 2144 * Externally visible method for sending or queueing messages or data. 2145 ***********************************************************************/ 2146 2147 /* 2148 * The module code should have filled out the item correctly by this stage: 2149 * Common: 2150 * reference to destination node. 2151 * Reference to destination rcv hook if relevant. 2152 * Data: 2153 * pointer to mbuf 2154 * Control_Message: 2155 * pointer to msg. 2156 * ID of original sender node. (return address) 2157 * Function: 2158 * Function pointer 2159 * void * argument 2160 * integer argument 2161 * 2162 * The nodes have several routines and macros to help with this task: 2163 */ 2164 2165 int 2166 ng_snd_item(item_p item, int flags) 2167 { 2168 hook_p hook = NGI_HOOK(item); 2169 node_p node = NGI_NODE(item); 2170 int queue, rw; 2171 struct ng_queue * ngq = &node->nd_input_queue; 2172 int error = 0; 2173 2174 #ifdef NETGRAPH_DEBUG 2175 _ngi_check(item, __FILE__, __LINE__); 2176 #endif 2177 2178 queue = (flags & NG_QUEUE) ? 1 : 0; 2179 2180 if (item == NULL) { 2181 TRAP_ERROR(); 2182 return (EINVAL); /* failed to get queue element */ 2183 } 2184 if (node == NULL) { 2185 NG_FREE_ITEM(item); 2186 TRAP_ERROR(); 2187 return (EINVAL); /* No address */ 2188 } 2189 switch(item->el_flags & NGQF_TYPE) { 2190 case NGQF_DATA: 2191 /* 2192 * DATA MESSAGE 2193 * Delivered to a node via a non-optional hook. 2194 * Both should be present in the item even though 2195 * the node is derivable from the hook. 2196 * References are held on both by the item. 2197 */ 2198 2199 /* Protect nodes from sending NULL pointers 2200 * to each other 2201 */ 2202 if (NGI_M(item) == NULL) 2203 return (EINVAL); 2204 2205 CHECK_DATA_MBUF(NGI_M(item)); 2206 if (hook == NULL) { 2207 NG_FREE_ITEM(item); 2208 TRAP_ERROR(); 2209 return(EINVAL); 2210 } 2211 if ((NG_HOOK_NOT_VALID(hook)) 2212 || (NG_NODE_NOT_VALID(NG_HOOK_NODE(hook)))) { 2213 NG_FREE_ITEM(item); 2214 return (ENOTCONN); 2215 } 2216 if ((hook->hk_flags & HK_QUEUE)) { 2217 queue = 1; 2218 } 2219 break; 2220 case NGQF_MESG: 2221 /* 2222 * CONTROL MESSAGE 2223 * Delivered to a node. 2224 * Hook is optional. 2225 * References are held by the item on the node and 2226 * the hook if it is present. 2227 */ 2228 if (hook && (hook->hk_flags & HK_QUEUE)) { 2229 queue = 1; 2230 } 2231 break; 2232 case NGQF_FN: 2233 break; 2234 default: 2235 NG_FREE_ITEM(item); 2236 TRAP_ERROR(); 2237 return (EINVAL); 2238 } 2239 switch(item->el_flags & NGQF_RW) { 2240 case NGQF_READER: 2241 rw = NGQRW_R; 2242 break; 2243 case NGQF_WRITER: 2244 rw = NGQRW_W; 2245 break; 2246 default: 2247 panic("%s: invalid item flags %lx", __func__, item->el_flags); 2248 } 2249 2250 /* 2251 * If the node specifies single threading, force writer semantics. 2252 * Similarly, the node may say one hook always produces writers. 2253 * These are overrides. 2254 */ 2255 if ((node->nd_flags & NGF_FORCE_WRITER) 2256 || (hook && (hook->hk_flags & HK_FORCE_WRITER))) 2257 rw = NGQRW_W; 2258 2259 if (queue) { 2260 /* Put it on the queue for that node*/ 2261 #ifdef NETGRAPH_DEBUG 2262 _ngi_check(item, __FILE__, __LINE__); 2263 #endif 2264 mtx_lock_spin(&(ngq->q_mtx)); 2265 ng_queue_rw(ngq, item, rw); 2266 mtx_unlock_spin(&(ngq->q_mtx)); 2267 2268 if (flags & NG_PROGRESS) 2269 return (EINPROGRESS); 2270 else 2271 return (0); 2272 } 2273 2274 /* 2275 * We already decided how we will be queueud or treated. 2276 * Try get the appropriate operating permission. 2277 */ 2278 if (rw == NGQRW_R) 2279 item = ng_acquire_read(ngq, item); 2280 else 2281 item = ng_acquire_write(ngq, item); 2282 2283 2284 if (item == NULL) { 2285 if (flags & NG_PROGRESS) 2286 return (EINPROGRESS); 2287 else 2288 return (0); 2289 } 2290 2291 #ifdef NETGRAPH_DEBUG 2292 _ngi_check(item, __FILE__, __LINE__); 2293 #endif 2294 2295 NGI_GET_NODE(item, node); /* zaps stored node */ 2296 2297 error = ng_apply_item(node, item, rw); /* drops r/w lock when done */ 2298 2299 /* 2300 * If the node goes away when we remove the reference, 2301 * whatever we just did caused it.. whatever we do, DO NOT 2302 * access the node again! 2303 */ 2304 if (NG_NODE_UNREF(node) == 0) { 2305 return (error); 2306 } 2307 2308 mtx_lock_spin(&(ngq->q_mtx)); 2309 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2310 ng_setisr(ngq->q_node); 2311 mtx_unlock_spin(&(ngq->q_mtx)); 2312 2313 return (error); 2314 } 2315 2316 /* 2317 * We have an item that was possibly queued somewhere. 2318 * It should contain all the information needed 2319 * to run it on the appropriate node/hook. 2320 */ 2321 static int 2322 ng_apply_item(node_p node, item_p item, int rw) 2323 { 2324 hook_p hook; 2325 int error = 0; 2326 ng_rcvdata_t *rcvdata; 2327 ng_rcvmsg_t *rcvmsg; 2328 ng_apply_t *apply = NULL; 2329 void *context = NULL; 2330 2331 NGI_GET_HOOK(item, hook); /* clears stored hook */ 2332 #ifdef NETGRAPH_DEBUG 2333 _ngi_check(item, __FILE__, __LINE__); 2334 #endif 2335 2336 /* 2337 * If the item has an "apply" callback, store it. 2338 * Clear item's callback immediately, to avoid an extra call if 2339 * the item is reused by the destination node. 2340 */ 2341 if (item->apply != NULL) { 2342 apply = item->apply; 2343 context = item->context; 2344 item->apply = NULL; 2345 } 2346 2347 switch (item->el_flags & NGQF_TYPE) { 2348 case NGQF_DATA: 2349 /* 2350 * Check things are still ok as when we were queued. 2351 */ 2352 if ((hook == NULL) 2353 || NG_HOOK_NOT_VALID(hook) 2354 || NG_NODE_NOT_VALID(node) ) { 2355 error = EIO; 2356 NG_FREE_ITEM(item); 2357 break; 2358 } 2359 /* 2360 * If no receive method, just silently drop it. 2361 * Give preference to the hook over-ride method 2362 */ 2363 if ((!(rcvdata = hook->hk_rcvdata)) 2364 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) { 2365 error = 0; 2366 NG_FREE_ITEM(item); 2367 break; 2368 } 2369 error = (*rcvdata)(hook, item); 2370 break; 2371 case NGQF_MESG: 2372 if (hook) { 2373 if (NG_HOOK_NOT_VALID(hook)) { 2374 /* 2375 * The hook has been zapped then we can't 2376 * use it. Immediatly drop its reference. 2377 * The message may not need it. 2378 */ 2379 NG_HOOK_UNREF(hook); 2380 hook = NULL; 2381 } 2382 } 2383 /* 2384 * Similarly, if the node is a zombie there is 2385 * nothing we can do with it, drop everything. 2386 */ 2387 if (NG_NODE_NOT_VALID(node)) { 2388 TRAP_ERROR(); 2389 error = EINVAL; 2390 NG_FREE_ITEM(item); 2391 } else { 2392 /* 2393 * Call the appropriate message handler for the object. 2394 * It is up to the message handler to free the message. 2395 * If it's a generic message, handle it generically, 2396 * otherwise call the type's message handler 2397 * (if it exists) 2398 * XXX (race). Remember that a queued message may 2399 * reference a node or hook that has just been 2400 * invalidated. It will exist as the queue code 2401 * is holding a reference, but.. 2402 */ 2403 2404 struct ng_mesg *msg = NGI_MSG(item); 2405 2406 /* 2407 * check if the generic handler owns it. 2408 */ 2409 if ((msg->header.typecookie == NGM_GENERIC_COOKIE) 2410 && ((msg->header.flags & NGF_RESP) == 0)) { 2411 error = ng_generic_msg(node, item, hook); 2412 break; 2413 } 2414 /* 2415 * Now see if there is a handler (hook or node specific) 2416 * in the target node. If none, silently discard. 2417 */ 2418 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) 2419 && (!(rcvmsg = node->nd_type->rcvmsg))) { 2420 TRAP_ERROR(); 2421 error = 0; 2422 NG_FREE_ITEM(item); 2423 break; 2424 } 2425 error = (*rcvmsg)(node, item, hook); 2426 } 2427 break; 2428 case NGQF_FN: 2429 /* 2430 * We have to implicitly trust the hook, 2431 * as some of these are used for system purposes 2432 * where the hook is invalid. In the case of 2433 * the shutdown message we allow it to hit 2434 * even if the node is invalid. 2435 */ 2436 if ((NG_NODE_NOT_VALID(node)) 2437 && (NGI_FN(item) != &ng_rmnode)) { 2438 TRAP_ERROR(); 2439 error = EINVAL; 2440 NG_FREE_ITEM(item); 2441 break; 2442 } 2443 (*NGI_FN(item))(node, hook, NGI_ARG1(item), NGI_ARG2(item)); 2444 NG_FREE_ITEM(item); 2445 break; 2446 2447 } 2448 /* 2449 * We held references on some of the resources 2450 * that we took from the item. Now that we have 2451 * finished doing everything, drop those references. 2452 */ 2453 if (hook) { 2454 NG_HOOK_UNREF(hook); 2455 } 2456 2457 if (rw == NGQRW_R) { 2458 ng_leave_read(&node->nd_input_queue); 2459 } else { 2460 ng_leave_write(&node->nd_input_queue); 2461 } 2462 2463 /* Apply callback. */ 2464 if (apply != NULL) 2465 (*apply)(context, error); 2466 2467 return (error); 2468 } 2469 2470 /*********************************************************************** 2471 * Implement the 'generic' control messages 2472 ***********************************************************************/ 2473 static int 2474 ng_generic_msg(node_p here, item_p item, hook_p lasthook) 2475 { 2476 int error = 0; 2477 struct ng_mesg *msg; 2478 struct ng_mesg *resp = NULL; 2479 2480 NGI_GET_MSG(item, msg); 2481 if (msg->header.typecookie != NGM_GENERIC_COOKIE) { 2482 TRAP_ERROR(); 2483 error = EINVAL; 2484 goto out; 2485 } 2486 switch (msg->header.cmd) { 2487 case NGM_SHUTDOWN: 2488 ng_rmnode(here, NULL, NULL, 0); 2489 break; 2490 case NGM_MKPEER: 2491 { 2492 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data; 2493 2494 if (msg->header.arglen != sizeof(*mkp)) { 2495 TRAP_ERROR(); 2496 error = EINVAL; 2497 break; 2498 } 2499 mkp->type[sizeof(mkp->type) - 1] = '\0'; 2500 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0'; 2501 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0'; 2502 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type); 2503 break; 2504 } 2505 case NGM_CONNECT: 2506 { 2507 struct ngm_connect *const con = 2508 (struct ngm_connect *) msg->data; 2509 node_p node2; 2510 2511 if (msg->header.arglen != sizeof(*con)) { 2512 TRAP_ERROR(); 2513 error = EINVAL; 2514 break; 2515 } 2516 con->path[sizeof(con->path) - 1] = '\0'; 2517 con->ourhook[sizeof(con->ourhook) - 1] = '\0'; 2518 con->peerhook[sizeof(con->peerhook) - 1] = '\0'; 2519 /* Don't forget we get a reference.. */ 2520 error = ng_path2noderef(here, con->path, &node2, NULL); 2521 if (error) 2522 break; 2523 error = ng_con_nodes(here, con->ourhook, node2, con->peerhook); 2524 NG_NODE_UNREF(node2); 2525 break; 2526 } 2527 case NGM_NAME: 2528 { 2529 struct ngm_name *const nam = (struct ngm_name *) msg->data; 2530 2531 if (msg->header.arglen != sizeof(*nam)) { 2532 TRAP_ERROR(); 2533 error = EINVAL; 2534 break; 2535 } 2536 nam->name[sizeof(nam->name) - 1] = '\0'; 2537 error = ng_name_node(here, nam->name); 2538 break; 2539 } 2540 case NGM_RMHOOK: 2541 { 2542 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data; 2543 hook_p hook; 2544 2545 if (msg->header.arglen != sizeof(*rmh)) { 2546 TRAP_ERROR(); 2547 error = EINVAL; 2548 break; 2549 } 2550 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0'; 2551 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL) 2552 ng_destroy_hook(hook); 2553 break; 2554 } 2555 case NGM_NODEINFO: 2556 { 2557 struct nodeinfo *ni; 2558 2559 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT); 2560 if (resp == NULL) { 2561 error = ENOMEM; 2562 break; 2563 } 2564 2565 /* Fill in node info */ 2566 ni = (struct nodeinfo *) resp->data; 2567 if (NG_NODE_HAS_NAME(here)) 2568 strcpy(ni->name, NG_NODE_NAME(here)); 2569 strcpy(ni->type, here->nd_type->name); 2570 ni->id = ng_node2ID(here); 2571 ni->hooks = here->nd_numhooks; 2572 break; 2573 } 2574 case NGM_LISTHOOKS: 2575 { 2576 const int nhooks = here->nd_numhooks; 2577 struct hooklist *hl; 2578 struct nodeinfo *ni; 2579 hook_p hook; 2580 2581 /* Get response struct */ 2582 NG_MKRESPONSE(resp, msg, sizeof(*hl) 2583 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT); 2584 if (resp == NULL) { 2585 error = ENOMEM; 2586 break; 2587 } 2588 hl = (struct hooklist *) resp->data; 2589 ni = &hl->nodeinfo; 2590 2591 /* Fill in node info */ 2592 if (NG_NODE_HAS_NAME(here)) 2593 strcpy(ni->name, NG_NODE_NAME(here)); 2594 strcpy(ni->type, here->nd_type->name); 2595 ni->id = ng_node2ID(here); 2596 2597 /* Cycle through the linked list of hooks */ 2598 ni->hooks = 0; 2599 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) { 2600 struct linkinfo *const link = &hl->link[ni->hooks]; 2601 2602 if (ni->hooks >= nhooks) { 2603 log(LOG_ERR, "%s: number of %s changed\n", 2604 __func__, "hooks"); 2605 break; 2606 } 2607 if (NG_HOOK_NOT_VALID(hook)) 2608 continue; 2609 strcpy(link->ourhook, NG_HOOK_NAME(hook)); 2610 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook)); 2611 if (NG_PEER_NODE_NAME(hook)[0] != '\0') 2612 strcpy(link->nodeinfo.name, 2613 NG_PEER_NODE_NAME(hook)); 2614 strcpy(link->nodeinfo.type, 2615 NG_PEER_NODE(hook)->nd_type->name); 2616 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook)); 2617 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks; 2618 ni->hooks++; 2619 } 2620 break; 2621 } 2622 2623 case NGM_LISTNAMES: 2624 case NGM_LISTNODES: 2625 { 2626 const int unnamed = (msg->header.cmd == NGM_LISTNODES); 2627 struct namelist *nl; 2628 node_p node; 2629 int num = 0; 2630 2631 mtx_lock(&ng_nodelist_mtx); 2632 /* Count number of nodes */ 2633 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2634 if (NG_NODE_IS_VALID(node) 2635 && (unnamed || NG_NODE_HAS_NAME(node))) { 2636 num++; 2637 } 2638 } 2639 mtx_unlock(&ng_nodelist_mtx); 2640 2641 /* Get response struct */ 2642 NG_MKRESPONSE(resp, msg, sizeof(*nl) 2643 + (num * sizeof(struct nodeinfo)), M_NOWAIT); 2644 if (resp == NULL) { 2645 error = ENOMEM; 2646 break; 2647 } 2648 nl = (struct namelist *) resp->data; 2649 2650 /* Cycle through the linked list of nodes */ 2651 nl->numnames = 0; 2652 mtx_lock(&ng_nodelist_mtx); 2653 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2654 struct nodeinfo *const np = &nl->nodeinfo[nl->numnames]; 2655 2656 if (nl->numnames >= num) { 2657 log(LOG_ERR, "%s: number of %s changed\n", 2658 __func__, "nodes"); 2659 break; 2660 } 2661 if (NG_NODE_NOT_VALID(node)) 2662 continue; 2663 if (!unnamed && (! NG_NODE_HAS_NAME(node))) 2664 continue; 2665 if (NG_NODE_HAS_NAME(node)) 2666 strcpy(np->name, NG_NODE_NAME(node)); 2667 strcpy(np->type, node->nd_type->name); 2668 np->id = ng_node2ID(node); 2669 np->hooks = node->nd_numhooks; 2670 nl->numnames++; 2671 } 2672 mtx_unlock(&ng_nodelist_mtx); 2673 break; 2674 } 2675 2676 case NGM_LISTTYPES: 2677 { 2678 struct typelist *tl; 2679 struct ng_type *type; 2680 int num = 0; 2681 2682 mtx_lock(&ng_typelist_mtx); 2683 /* Count number of types */ 2684 LIST_FOREACH(type, &ng_typelist, types) { 2685 num++; 2686 } 2687 mtx_unlock(&ng_typelist_mtx); 2688 2689 /* Get response struct */ 2690 NG_MKRESPONSE(resp, msg, sizeof(*tl) 2691 + (num * sizeof(struct typeinfo)), M_NOWAIT); 2692 if (resp == NULL) { 2693 error = ENOMEM; 2694 break; 2695 } 2696 tl = (struct typelist *) resp->data; 2697 2698 /* Cycle through the linked list of types */ 2699 tl->numtypes = 0; 2700 mtx_lock(&ng_typelist_mtx); 2701 LIST_FOREACH(type, &ng_typelist, types) { 2702 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes]; 2703 2704 if (tl->numtypes >= num) { 2705 log(LOG_ERR, "%s: number of %s changed\n", 2706 __func__, "types"); 2707 break; 2708 } 2709 strcpy(tp->type_name, type->name); 2710 tp->numnodes = type->refs - 1; /* don't count list */ 2711 tl->numtypes++; 2712 } 2713 mtx_unlock(&ng_typelist_mtx); 2714 break; 2715 } 2716 2717 case NGM_BINARY2ASCII: 2718 { 2719 int bufSize = 20 * 1024; /* XXX hard coded constant */ 2720 const struct ng_parse_type *argstype; 2721 const struct ng_cmdlist *c; 2722 struct ng_mesg *binary, *ascii; 2723 2724 /* Data area must contain a valid netgraph message */ 2725 binary = (struct ng_mesg *)msg->data; 2726 if (msg->header.arglen < sizeof(struct ng_mesg) || 2727 (msg->header.arglen - sizeof(struct ng_mesg) < 2728 binary->header.arglen)) { 2729 TRAP_ERROR(); 2730 error = EINVAL; 2731 break; 2732 } 2733 2734 /* Get a response message with lots of room */ 2735 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT); 2736 if (resp == NULL) { 2737 error = ENOMEM; 2738 break; 2739 } 2740 ascii = (struct ng_mesg *)resp->data; 2741 2742 /* Copy binary message header to response message payload */ 2743 bcopy(binary, ascii, sizeof(*binary)); 2744 2745 /* Find command by matching typecookie and command number */ 2746 for (c = here->nd_type->cmdlist; 2747 c != NULL && c->name != NULL; c++) { 2748 if (binary->header.typecookie == c->cookie 2749 && binary->header.cmd == c->cmd) 2750 break; 2751 } 2752 if (c == NULL || c->name == NULL) { 2753 for (c = ng_generic_cmds; c->name != NULL; c++) { 2754 if (binary->header.typecookie == c->cookie 2755 && binary->header.cmd == c->cmd) 2756 break; 2757 } 2758 if (c->name == NULL) { 2759 NG_FREE_MSG(resp); 2760 error = ENOSYS; 2761 break; 2762 } 2763 } 2764 2765 /* Convert command name to ASCII */ 2766 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr), 2767 "%s", c->name); 2768 2769 /* Convert command arguments to ASCII */ 2770 argstype = (binary->header.flags & NGF_RESP) ? 2771 c->respType : c->mesgType; 2772 if (argstype == NULL) { 2773 *ascii->data = '\0'; 2774 } else { 2775 if ((error = ng_unparse(argstype, 2776 (u_char *)binary->data, 2777 ascii->data, bufSize)) != 0) { 2778 NG_FREE_MSG(resp); 2779 break; 2780 } 2781 } 2782 2783 /* Return the result as struct ng_mesg plus ASCII string */ 2784 bufSize = strlen(ascii->data) + 1; 2785 ascii->header.arglen = bufSize; 2786 resp->header.arglen = sizeof(*ascii) + bufSize; 2787 break; 2788 } 2789 2790 case NGM_ASCII2BINARY: 2791 { 2792 int bufSize = 2000; /* XXX hard coded constant */ 2793 const struct ng_cmdlist *c; 2794 const struct ng_parse_type *argstype; 2795 struct ng_mesg *ascii, *binary; 2796 int off = 0; 2797 2798 /* Data area must contain at least a struct ng_mesg + '\0' */ 2799 ascii = (struct ng_mesg *)msg->data; 2800 if ((msg->header.arglen < sizeof(*ascii) + 1) || 2801 (ascii->header.arglen < 1) || 2802 (msg->header.arglen < sizeof(*ascii) + 2803 ascii->header.arglen)) { 2804 TRAP_ERROR(); 2805 error = EINVAL; 2806 break; 2807 } 2808 ascii->data[ascii->header.arglen - 1] = '\0'; 2809 2810 /* Get a response message with lots of room */ 2811 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT); 2812 if (resp == NULL) { 2813 error = ENOMEM; 2814 break; 2815 } 2816 binary = (struct ng_mesg *)resp->data; 2817 2818 /* Copy ASCII message header to response message payload */ 2819 bcopy(ascii, binary, sizeof(*ascii)); 2820 2821 /* Find command by matching ASCII command string */ 2822 for (c = here->nd_type->cmdlist; 2823 c != NULL && c->name != NULL; c++) { 2824 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2825 break; 2826 } 2827 if (c == NULL || c->name == NULL) { 2828 for (c = ng_generic_cmds; c->name != NULL; c++) { 2829 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2830 break; 2831 } 2832 if (c->name == NULL) { 2833 NG_FREE_MSG(resp); 2834 error = ENOSYS; 2835 break; 2836 } 2837 } 2838 2839 /* Convert command name to binary */ 2840 binary->header.cmd = c->cmd; 2841 binary->header.typecookie = c->cookie; 2842 2843 /* Convert command arguments to binary */ 2844 argstype = (binary->header.flags & NGF_RESP) ? 2845 c->respType : c->mesgType; 2846 if (argstype == NULL) { 2847 bufSize = 0; 2848 } else { 2849 if ((error = ng_parse(argstype, ascii->data, 2850 &off, (u_char *)binary->data, &bufSize)) != 0) { 2851 NG_FREE_MSG(resp); 2852 break; 2853 } 2854 } 2855 2856 /* Return the result */ 2857 binary->header.arglen = bufSize; 2858 resp->header.arglen = sizeof(*binary) + bufSize; 2859 break; 2860 } 2861 2862 case NGM_TEXT_CONFIG: 2863 case NGM_TEXT_STATUS: 2864 /* 2865 * This one is tricky as it passes the command down to the 2866 * actual node, even though it is a generic type command. 2867 * This means we must assume that the item/msg is already freed 2868 * when control passes back to us. 2869 */ 2870 if (here->nd_type->rcvmsg != NULL) { 2871 NGI_MSG(item) = msg; /* put it back as we found it */ 2872 return((*here->nd_type->rcvmsg)(here, item, lasthook)); 2873 } 2874 /* Fall through if rcvmsg not supported */ 2875 default: 2876 TRAP_ERROR(); 2877 error = EINVAL; 2878 } 2879 /* 2880 * Sometimes a generic message may be statically allocated 2881 * to avoid problems with allocating when in tight memeory situations. 2882 * Don't free it if it is so. 2883 * I break them appart here, because erros may cause a free if the item 2884 * in which case we'd be doing it twice. 2885 * they are kept together above, to simplify freeing. 2886 */ 2887 out: 2888 NG_RESPOND_MSG(error, here, item, resp); 2889 if (msg) 2890 NG_FREE_MSG(msg); 2891 return (error); 2892 } 2893 2894 /************************************************************************ 2895 Queue element get/free routines 2896 ************************************************************************/ 2897 2898 uma_zone_t ng_qzone; 2899 static int maxalloc = 512; /* limit the damage of a leak */ 2900 2901 TUNABLE_INT("net.graph.maxalloc", &maxalloc); 2902 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc, 2903 0, "Maximum number of queue items to allocate"); 2904 2905 #ifdef NETGRAPH_DEBUG 2906 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist); 2907 static int allocated; /* number of items malloc'd */ 2908 #endif 2909 2910 /* 2911 * Get a queue entry. 2912 * This is usually called when a packet first enters netgraph. 2913 * By definition, this is usually from an interrupt, or from a user. 2914 * Users are not so important, but try be quick for the times that it's 2915 * an interrupt. 2916 */ 2917 static __inline item_p 2918 ng_getqblk(int flags) 2919 { 2920 item_p item = NULL; 2921 int wait; 2922 2923 wait = (flags & NG_WAITOK) ? M_WAITOK : M_NOWAIT; 2924 2925 item = uma_zalloc(ng_qzone, wait | M_ZERO); 2926 2927 #ifdef NETGRAPH_DEBUG 2928 if (item) { 2929 mtx_lock(&ngq_mtx); 2930 TAILQ_INSERT_TAIL(&ng_itemlist, item, all); 2931 allocated++; 2932 mtx_unlock(&ngq_mtx); 2933 } 2934 #endif 2935 2936 return (item); 2937 } 2938 2939 /* 2940 * Release a queue entry 2941 */ 2942 void 2943 ng_free_item(item_p item) 2944 { 2945 KASSERT(item->apply == NULL, ("%s: leaking apply callback", __func__)); 2946 2947 /* 2948 * The item may hold resources on it's own. We need to free 2949 * these before we can free the item. What they are depends upon 2950 * what kind of item it is. it is important that nodes zero 2951 * out pointers to resources that they remove from the item 2952 * or we release them again here. 2953 */ 2954 switch (item->el_flags & NGQF_TYPE) { 2955 case NGQF_DATA: 2956 /* If we have an mbuf still attached.. */ 2957 NG_FREE_M(_NGI_M(item)); 2958 break; 2959 case NGQF_MESG: 2960 _NGI_RETADDR(item) = 0; 2961 NG_FREE_MSG(_NGI_MSG(item)); 2962 break; 2963 case NGQF_FN: 2964 /* nothing to free really, */ 2965 _NGI_FN(item) = NULL; 2966 _NGI_ARG1(item) = NULL; 2967 _NGI_ARG2(item) = 0; 2968 case NGQF_UNDEF: 2969 break; 2970 } 2971 /* If we still have a node or hook referenced... */ 2972 _NGI_CLR_NODE(item); 2973 _NGI_CLR_HOOK(item); 2974 2975 #ifdef NETGRAPH_DEBUG 2976 mtx_lock(&ngq_mtx); 2977 TAILQ_REMOVE(&ng_itemlist, item, all); 2978 allocated--; 2979 mtx_unlock(&ngq_mtx); 2980 #endif 2981 uma_zfree(ng_qzone, item); 2982 } 2983 2984 /************************************************************************ 2985 Module routines 2986 ************************************************************************/ 2987 2988 /* 2989 * Handle the loading/unloading of a netgraph node type module 2990 */ 2991 int 2992 ng_mod_event(module_t mod, int event, void *data) 2993 { 2994 struct ng_type *const type = data; 2995 int s, error = 0; 2996 2997 switch (event) { 2998 case MOD_LOAD: 2999 3000 /* Register new netgraph node type */ 3001 s = splnet(); 3002 if ((error = ng_newtype(type)) != 0) { 3003 splx(s); 3004 break; 3005 } 3006 3007 /* Call type specific code */ 3008 if (type->mod_event != NULL) 3009 if ((error = (*type->mod_event)(mod, event, data))) { 3010 mtx_lock(&ng_typelist_mtx); 3011 type->refs--; /* undo it */ 3012 LIST_REMOVE(type, types); 3013 mtx_unlock(&ng_typelist_mtx); 3014 } 3015 splx(s); 3016 break; 3017 3018 case MOD_UNLOAD: 3019 s = splnet(); 3020 if (type->refs > 1) { /* make sure no nodes exist! */ 3021 error = EBUSY; 3022 } else { 3023 if (type->refs == 0) { 3024 /* failed load, nothing to undo */ 3025 splx(s); 3026 break; 3027 } 3028 if (type->mod_event != NULL) { /* check with type */ 3029 error = (*type->mod_event)(mod, event, data); 3030 if (error != 0) { /* type refuses.. */ 3031 splx(s); 3032 break; 3033 } 3034 } 3035 mtx_lock(&ng_typelist_mtx); 3036 LIST_REMOVE(type, types); 3037 mtx_unlock(&ng_typelist_mtx); 3038 } 3039 splx(s); 3040 break; 3041 3042 default: 3043 if (type->mod_event != NULL) 3044 error = (*type->mod_event)(mod, event, data); 3045 else 3046 error = EOPNOTSUPP; /* XXX ? */ 3047 break; 3048 } 3049 return (error); 3050 } 3051 3052 /* 3053 * Handle loading and unloading for this code. 3054 * The only thing we need to link into is the NETISR strucure. 3055 */ 3056 static int 3057 ngb_mod_event(module_t mod, int event, void *data) 3058 { 3059 int error = 0; 3060 3061 switch (event) { 3062 case MOD_LOAD: 3063 /* Initialize everything. */ 3064 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_SPIN); 3065 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL, 3066 MTX_DEF); 3067 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL, 3068 MTX_DEF); 3069 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL, 3070 MTX_DEF); 3071 mtx_init(&ng_topo_mtx, "netgraph topology mutex", NULL, 3072 MTX_DEF); 3073 #ifdef NETGRAPH_DEBUG 3074 mtx_init(&ngq_mtx, "netgraph item list mutex", NULL, 3075 MTX_DEF); 3076 #endif 3077 ng_qzone = uma_zcreate("NetGraph items", sizeof(struct ng_item), 3078 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0); 3079 uma_zone_set_max(ng_qzone, maxalloc); 3080 netisr_register(NETISR_NETGRAPH, (netisr_t *)ngintr, NULL, 3081 NETISR_MPSAFE); 3082 break; 3083 case MOD_UNLOAD: 3084 /* You cant unload it because an interface may be using it. */ 3085 error = EBUSY; 3086 break; 3087 default: 3088 error = EOPNOTSUPP; 3089 break; 3090 } 3091 return (error); 3092 } 3093 3094 static moduledata_t netgraph_mod = { 3095 "netgraph", 3096 ngb_mod_event, 3097 (NULL) 3098 }; 3099 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_MIDDLE); 3100 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family"); 3101 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,""); 3102 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, ""); 3103 3104 #ifdef NETGRAPH_DEBUG 3105 void 3106 dumphook (hook_p hook, char *file, int line) 3107 { 3108 printf("hook: name %s, %d refs, Last touched:\n", 3109 _NG_HOOK_NAME(hook), hook->hk_refs); 3110 printf(" Last active @ %s, line %d\n", 3111 hook->lastfile, hook->lastline); 3112 if (line) { 3113 printf(" problem discovered at file %s, line %d\n", file, line); 3114 } 3115 } 3116 3117 void 3118 dumpnode(node_p node, char *file, int line) 3119 { 3120 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n", 3121 _NG_NODE_ID(node), node->nd_type->name, 3122 node->nd_numhooks, node->nd_flags, 3123 node->nd_refs, node->nd_name); 3124 printf(" Last active @ %s, line %d\n", 3125 node->lastfile, node->lastline); 3126 if (line) { 3127 printf(" problem discovered at file %s, line %d\n", file, line); 3128 } 3129 } 3130 3131 void 3132 dumpitem(item_p item, char *file, int line) 3133 { 3134 printf(" ACTIVE item, last used at %s, line %d", 3135 item->lastfile, item->lastline); 3136 switch(item->el_flags & NGQF_TYPE) { 3137 case NGQF_DATA: 3138 printf(" - [data]\n"); 3139 break; 3140 case NGQF_MESG: 3141 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item)); 3142 break; 3143 case NGQF_FN: 3144 printf(" - fn@%p (%p, %p, %p, %d (%x))\n", 3145 item->body.fn.fn_fn, 3146 _NGI_NODE(item), 3147 _NGI_HOOK(item), 3148 item->body.fn.fn_arg1, 3149 item->body.fn.fn_arg2, 3150 item->body.fn.fn_arg2); 3151 break; 3152 case NGQF_UNDEF: 3153 printf(" - UNDEFINED!\n"); 3154 } 3155 if (line) { 3156 printf(" problem discovered at file %s, line %d\n", file, line); 3157 if (_NGI_NODE(item)) { 3158 printf("node %p ([%x])\n", 3159 _NGI_NODE(item), ng_node2ID(_NGI_NODE(item))); 3160 } 3161 } 3162 } 3163 3164 static void 3165 ng_dumpitems(void) 3166 { 3167 item_p item; 3168 int i = 1; 3169 TAILQ_FOREACH(item, &ng_itemlist, all) { 3170 printf("[%d] ", i++); 3171 dumpitem(item, NULL, 0); 3172 } 3173 } 3174 3175 static void 3176 ng_dumpnodes(void) 3177 { 3178 node_p node; 3179 int i = 1; 3180 mtx_lock(&ng_nodelist_mtx); 3181 SLIST_FOREACH(node, &ng_allnodes, nd_all) { 3182 printf("[%d] ", i++); 3183 dumpnode(node, NULL, 0); 3184 } 3185 mtx_unlock(&ng_nodelist_mtx); 3186 } 3187 3188 static void 3189 ng_dumphooks(void) 3190 { 3191 hook_p hook; 3192 int i = 1; 3193 mtx_lock(&ng_nodelist_mtx); 3194 SLIST_FOREACH(hook, &ng_allhooks, hk_all) { 3195 printf("[%d] ", i++); 3196 dumphook(hook, NULL, 0); 3197 } 3198 mtx_unlock(&ng_nodelist_mtx); 3199 } 3200 3201 static int 3202 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS) 3203 { 3204 int error; 3205 int val; 3206 int i; 3207 3208 val = allocated; 3209 i = 1; 3210 error = sysctl_handle_int(oidp, &val, sizeof(int), req); 3211 if (error != 0 || req->newptr == NULL) 3212 return (error); 3213 if (val == 42) { 3214 ng_dumpitems(); 3215 ng_dumpnodes(); 3216 ng_dumphooks(); 3217 } 3218 return (0); 3219 } 3220 3221 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW, 3222 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items"); 3223 #endif /* NETGRAPH_DEBUG */ 3224 3225 3226 /*********************************************************************** 3227 * Worklist routines 3228 **********************************************************************/ 3229 /* NETISR thread enters here */ 3230 /* 3231 * Pick a node off the list of nodes with work, 3232 * try get an item to process off it. 3233 * If there are no more, remove the node from the list. 3234 */ 3235 static void 3236 ngintr(void) 3237 { 3238 item_p item; 3239 node_p node = NULL; 3240 3241 for (;;) { 3242 mtx_lock_spin(&ng_worklist_mtx); 3243 node = TAILQ_FIRST(&ng_worklist); 3244 if (!node) { 3245 mtx_unlock_spin(&ng_worklist_mtx); 3246 break; 3247 } 3248 node->nd_flags &= ~NGF_WORKQ; 3249 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3250 mtx_unlock_spin(&ng_worklist_mtx); 3251 CTR3(KTR_NET, "%20s: node [%x] (%p) taken off worklist", 3252 __func__, node->nd_ID, node); 3253 /* 3254 * We have the node. We also take over the reference 3255 * that the list had on it. 3256 * Now process as much as you can, until it won't 3257 * let you have another item off the queue. 3258 * All this time, keep the reference 3259 * that lets us be sure that the node still exists. 3260 * Let the reference go at the last minute. 3261 * ng_dequeue will put us back on the worklist 3262 * if there is more too do. This may be of use if there 3263 * are Multiple Processors and multiple Net threads in the 3264 * future. 3265 */ 3266 for (;;) { 3267 int rw; 3268 3269 mtx_lock_spin(&node->nd_input_queue.q_mtx); 3270 item = ng_dequeue(&node->nd_input_queue, &rw); 3271 if (item == NULL) { 3272 mtx_unlock_spin(&node->nd_input_queue.q_mtx); 3273 break; /* go look for another node */ 3274 } else { 3275 mtx_unlock_spin(&node->nd_input_queue.q_mtx); 3276 NGI_GET_NODE(item, node); /* zaps stored node */ 3277 ng_apply_item(node, item, rw); 3278 NG_NODE_UNREF(node); 3279 } 3280 } 3281 NG_NODE_UNREF(node); 3282 } 3283 } 3284 3285 static void 3286 ng_worklist_remove(node_p node) 3287 { 3288 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED); 3289 3290 mtx_lock_spin(&ng_worklist_mtx); 3291 if (node->nd_flags & NGF_WORKQ) { 3292 node->nd_flags &= ~NGF_WORKQ; 3293 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3294 mtx_unlock_spin(&ng_worklist_mtx); 3295 NG_NODE_UNREF(node); 3296 CTR3(KTR_NET, "%20s: node [%x] (%p) removed from worklist", 3297 __func__, node->nd_ID, node); 3298 } else { 3299 mtx_unlock_spin(&ng_worklist_mtx); 3300 } 3301 } 3302 3303 /* 3304 * XXX 3305 * It's posible that a debugging NG_NODE_REF may need 3306 * to be outside the mutex zone 3307 */ 3308 static void 3309 ng_setisr(node_p node) 3310 { 3311 3312 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED); 3313 3314 if ((node->nd_flags & NGF_WORKQ) == 0) { 3315 /* 3316 * If we are not already on the work queue, 3317 * then put us on. 3318 */ 3319 node->nd_flags |= NGF_WORKQ; 3320 mtx_lock_spin(&ng_worklist_mtx); 3321 TAILQ_INSERT_TAIL(&ng_worklist, node, nd_work); 3322 mtx_unlock_spin(&ng_worklist_mtx); 3323 NG_NODE_REF(node); /* XXX fafe in mutex? */ 3324 CTR3(KTR_NET, "%20s: node [%x] (%p) put on worklist", __func__, 3325 node->nd_ID, node); 3326 } else 3327 CTR3(KTR_NET, "%20s: node [%x] (%p) already on worklist", 3328 __func__, node->nd_ID, node); 3329 schednetisr(NETISR_NETGRAPH); 3330 } 3331 3332 3333 /*********************************************************************** 3334 * Externally useable functions to set up a queue item ready for sending 3335 ***********************************************************************/ 3336 3337 #ifdef NETGRAPH_DEBUG 3338 #define ITEM_DEBUG_CHECKS \ 3339 do { \ 3340 if (NGI_NODE(item) ) { \ 3341 printf("item already has node"); \ 3342 kdb_enter("has node"); \ 3343 NGI_CLR_NODE(item); \ 3344 } \ 3345 if (NGI_HOOK(item) ) { \ 3346 printf("item already has hook"); \ 3347 kdb_enter("has hook"); \ 3348 NGI_CLR_HOOK(item); \ 3349 } \ 3350 } while (0) 3351 #else 3352 #define ITEM_DEBUG_CHECKS 3353 #endif 3354 3355 /* 3356 * Put mbuf into the item. 3357 * Hook and node references will be removed when the item is dequeued. 3358 * (or equivalent) 3359 * (XXX) Unsafe because no reference held by peer on remote node. 3360 * remote node might go away in this timescale. 3361 * We know the hooks can't go away because that would require getting 3362 * a writer item on both nodes and we must have at least a reader 3363 * here to be able to do this. 3364 * Note that the hook loaded is the REMOTE hook. 3365 * 3366 * This is possibly in the critical path for new data. 3367 */ 3368 item_p 3369 ng_package_data(struct mbuf *m, int flags) 3370 { 3371 item_p item; 3372 3373 if ((item = ng_getqblk(flags)) == NULL) { 3374 NG_FREE_M(m); 3375 return (NULL); 3376 } 3377 ITEM_DEBUG_CHECKS; 3378 item->el_flags = NGQF_DATA | NGQF_READER; 3379 item->el_next = NULL; 3380 NGI_M(item) = m; 3381 return (item); 3382 } 3383 3384 /* 3385 * Allocate a queue item and put items into it.. 3386 * Evaluate the address as this will be needed to queue it and 3387 * to work out what some of the fields should be. 3388 * Hook and node references will be removed when the item is dequeued. 3389 * (or equivalent) 3390 */ 3391 item_p 3392 ng_package_msg(struct ng_mesg *msg, int flags) 3393 { 3394 item_p item; 3395 3396 if ((item = ng_getqblk(flags)) == NULL) { 3397 NG_FREE_MSG(msg); 3398 return (NULL); 3399 } 3400 ITEM_DEBUG_CHECKS; 3401 /* Messages items count as writers unless explicitly exempted. */ 3402 if (msg->header.cmd & NGM_READONLY) 3403 item->el_flags = NGQF_MESG | NGQF_READER; 3404 else 3405 item->el_flags = NGQF_MESG | NGQF_WRITER; 3406 item->el_next = NULL; 3407 /* 3408 * Set the current lasthook into the queue item 3409 */ 3410 NGI_MSG(item) = msg; 3411 NGI_RETADDR(item) = 0; 3412 return (item); 3413 } 3414 3415 3416 3417 #define SET_RETADDR(item, here, retaddr) \ 3418 do { /* Data or fn items don't have retaddrs */ \ 3419 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \ 3420 if (retaddr) { \ 3421 NGI_RETADDR(item) = retaddr; \ 3422 } else { \ 3423 /* \ 3424 * The old return address should be ok. \ 3425 * If there isn't one, use the address \ 3426 * here. \ 3427 */ \ 3428 if (NGI_RETADDR(item) == 0) { \ 3429 NGI_RETADDR(item) \ 3430 = ng_node2ID(here); \ 3431 } \ 3432 } \ 3433 } \ 3434 } while (0) 3435 3436 int 3437 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr) 3438 { 3439 hook_p peer; 3440 node_p peernode; 3441 ITEM_DEBUG_CHECKS; 3442 /* 3443 * Quick sanity check.. 3444 * Since a hook holds a reference on it's node, once we know 3445 * that the peer is still connected (even if invalid,) we know 3446 * that the peer node is present, though maybe invalid. 3447 */ 3448 if ((hook == NULL) 3449 || NG_HOOK_NOT_VALID(hook) 3450 || (NG_HOOK_PEER(hook) == NULL) 3451 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)) 3452 || NG_NODE_NOT_VALID(NG_PEER_NODE(hook))) { 3453 NG_FREE_ITEM(item); 3454 TRAP_ERROR(); 3455 return (ENETDOWN); 3456 } 3457 3458 /* 3459 * Transfer our interest to the other (peer) end. 3460 */ 3461 peer = NG_HOOK_PEER(hook); 3462 NG_HOOK_REF(peer); 3463 NGI_SET_HOOK(item, peer); 3464 peernode = NG_PEER_NODE(hook); 3465 NG_NODE_REF(peernode); 3466 NGI_SET_NODE(item, peernode); 3467 SET_RETADDR(item, here, retaddr); 3468 return (0); 3469 } 3470 3471 int 3472 ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr) 3473 { 3474 node_p dest = NULL; 3475 hook_p hook = NULL; 3476 int error; 3477 3478 ITEM_DEBUG_CHECKS; 3479 /* 3480 * Note that ng_path2noderef increments the reference count 3481 * on the node for us if it finds one. So we don't have to. 3482 */ 3483 error = ng_path2noderef(here, address, &dest, &hook); 3484 if (error) { 3485 NG_FREE_ITEM(item); 3486 return (error); 3487 } 3488 NGI_SET_NODE(item, dest); 3489 if ( hook) { 3490 NG_HOOK_REF(hook); /* don't let it go while on the queue */ 3491 NGI_SET_HOOK(item, hook); 3492 } 3493 SET_RETADDR(item, here, retaddr); 3494 return (0); 3495 } 3496 3497 int 3498 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr) 3499 { 3500 node_p dest; 3501 3502 ITEM_DEBUG_CHECKS; 3503 /* 3504 * Find the target node. 3505 */ 3506 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */ 3507 if (dest == NULL) { 3508 NG_FREE_ITEM(item); 3509 TRAP_ERROR(); 3510 return(EINVAL); 3511 } 3512 /* Fill out the contents */ 3513 NGI_SET_NODE(item, dest); 3514 NGI_CLR_HOOK(item); 3515 SET_RETADDR(item, here, retaddr); 3516 return (0); 3517 } 3518 3519 /* 3520 * special case to send a message to self (e.g. destroy node) 3521 * Possibly indicate an arrival hook too. 3522 * Useful for removing that hook :-) 3523 */ 3524 item_p 3525 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg) 3526 { 3527 item_p item; 3528 3529 /* 3530 * Find the target node. 3531 * If there is a HOOK argument, then use that in preference 3532 * to the address. 3533 */ 3534 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL) { 3535 NG_FREE_MSG(msg); 3536 return (NULL); 3537 } 3538 3539 /* Fill out the contents */ 3540 item->el_flags = NGQF_MESG | NGQF_WRITER; 3541 item->el_next = NULL; 3542 NG_NODE_REF(here); 3543 NGI_SET_NODE(item, here); 3544 if (hook) { 3545 NG_HOOK_REF(hook); 3546 NGI_SET_HOOK(item, hook); 3547 } 3548 NGI_MSG(item) = msg; 3549 NGI_RETADDR(item) = ng_node2ID(here); 3550 return (item); 3551 } 3552 3553 int 3554 ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2, 3555 int flags) 3556 { 3557 item_p item; 3558 3559 if ((item = ng_getqblk(flags)) == NULL) { 3560 return (ENOMEM); 3561 } 3562 item->el_flags = NGQF_FN | NGQF_WRITER; 3563 NG_NODE_REF(node); /* and one for the item */ 3564 NGI_SET_NODE(item, node); 3565 if (hook) { 3566 NG_HOOK_REF(hook); 3567 NGI_SET_HOOK(item, hook); 3568 } 3569 NGI_FN(item) = fn; 3570 NGI_ARG1(item) = arg1; 3571 NGI_ARG2(item) = arg2; 3572 return(ng_snd_item(item, flags)); 3573 } 3574 3575 /* 3576 * Official timeout routines for Netgraph nodes. 3577 */ 3578 static void 3579 ng_callout_trampoline(void *arg) 3580 { 3581 item_p item = arg; 3582 3583 ng_snd_item(item, 0); 3584 } 3585 3586 3587 int 3588 ng_callout(struct callout *c, node_p node, hook_p hook, int ticks, 3589 ng_item_fn *fn, void * arg1, int arg2) 3590 { 3591 item_p item, oitem; 3592 3593 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL) 3594 return (ENOMEM); 3595 3596 item->el_flags = NGQF_FN | NGQF_WRITER; 3597 NG_NODE_REF(node); /* and one for the item */ 3598 NGI_SET_NODE(item, node); 3599 if (hook) { 3600 NG_HOOK_REF(hook); 3601 NGI_SET_HOOK(item, hook); 3602 } 3603 NGI_FN(item) = fn; 3604 NGI_ARG1(item) = arg1; 3605 NGI_ARG2(item) = arg2; 3606 oitem = c->c_arg; 3607 if (callout_reset(c, ticks, &ng_callout_trampoline, item) == 1 && 3608 oitem != NULL) 3609 NG_FREE_ITEM(oitem); 3610 return (0); 3611 } 3612 3613 /* A special modified version of untimeout() */ 3614 int 3615 ng_uncallout(struct callout *c, node_p node) 3616 { 3617 item_p item; 3618 int rval; 3619 3620 KASSERT(c != NULL, ("ng_uncallout: NULL callout")); 3621 KASSERT(node != NULL, ("ng_uncallout: NULL node")); 3622 3623 rval = callout_stop(c); 3624 item = c->c_arg; 3625 /* Do an extra check */ 3626 if ((rval > 0) && (c->c_func == &ng_callout_trampoline) && 3627 (NGI_NODE(item) == node)) { 3628 /* 3629 * We successfully removed it from the queue before it ran 3630 * So now we need to unreference everything that was 3631 * given extra references. (NG_FREE_ITEM does this). 3632 */ 3633 NG_FREE_ITEM(item); 3634 } 3635 c->c_arg = NULL; 3636 3637 return (rval); 3638 } 3639 3640 /* 3641 * Set the address, if none given, give the node here. 3642 */ 3643 void 3644 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr) 3645 { 3646 if (retaddr) { 3647 NGI_RETADDR(item) = retaddr; 3648 } else { 3649 /* 3650 * The old return address should be ok. 3651 * If there isn't one, use the address here. 3652 */ 3653 NGI_RETADDR(item) = ng_node2ID(here); 3654 } 3655 } 3656 3657 #define TESTING 3658 #ifdef TESTING 3659 /* just test all the macros */ 3660 void 3661 ng_macro_test(item_p item); 3662 void 3663 ng_macro_test(item_p item) 3664 { 3665 node_p node = NULL; 3666 hook_p hook = NULL; 3667 struct mbuf *m; 3668 struct ng_mesg *msg; 3669 ng_ID_t retaddr; 3670 int error; 3671 3672 NGI_GET_M(item, m); 3673 NGI_GET_MSG(item, msg); 3674 retaddr = NGI_RETADDR(item); 3675 NG_SEND_DATA(error, hook, m, NULL); 3676 NG_SEND_DATA_ONLY(error, hook, m); 3677 NG_FWD_NEW_DATA(error, item, hook, m); 3678 NG_FWD_ITEM_HOOK(error, item, hook); 3679 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr); 3680 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr); 3681 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr); 3682 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr); 3683 } 3684 #endif /* TESTING */ 3685
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