1 /* 2 * ng_base.c 3 * 4 * Copyright (c) 1996-1999 Whistle Communications, Inc. 5 * All rights reserved. 6 * 7 * Subject to the following obligations and disclaimer of warranty, use and 8 * redistribution of this software, in source or object code forms, with or 9 * without modifications are expressly permitted by Whistle Communications; 10 * provided, however, that: 11 * 1. Any and all reproductions of the source or object code must include the 12 * copyright notice above and the following disclaimer of warranties; and 13 * 2. No rights are granted, in any manner or form, to use Whistle 14 * Communications, Inc. trademarks, including the mark "WHISTLE 15 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 16 * such appears in the above copyright notice or in the software. 17 * 18 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 19 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 20 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 21 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 22 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 23 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 24 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 25 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 26 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 27 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 28 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 29 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 30 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 31 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 32 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 33 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 34 * OF SUCH DAMAGE. 35 * 36 * Authors: Julian Elischer <julian@freebsd.org> 37 * Archie Cobbs <archie@freebsd.org> 38 * 39 * $FreeBSD$ 40 * $Whistle: ng_base.c,v 1.39 1999/01/28 23:54:53 julian Exp $ 41 */ 42 43 /* 44 * This file implements the base netgraph code. 45 */ 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/errno.h> 50 #include <sys/kernel.h> 51 #include <sys/malloc.h> 52 #include <sys/syslog.h> 53 #include <sys/sysctl.h> 54 #include <sys/linker.h> 55 #include <sys/queue.h> 56 #include <sys/mbuf.h> 57 #include <sys/ctype.h> 58 #include <machine/limits.h> 59 60 #include <net/netisr.h> 61 62 #include <netgraph/ng_message.h> 63 #include <netgraph/netgraph.h> 64 #include <netgraph/ng_parse.h> 65 66 MODULE_VERSION(netgraph, 1); 67 68 /* List of all active nodes */ 69 static LIST_HEAD(, ng_node) ng_nodelist; 70 static struct mtx ng_nodelist_mtx; 71 72 #ifdef NETGRAPH_DEBUG 73 74 static SLIST_HEAD(, ng_node) ng_allnodes; 75 static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */ 76 static SLIST_HEAD(, ng_hook) ng_allhooks; 77 static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */ 78 79 static void ng_dumpitems(void); 80 static void ng_dumpnodes(void); 81 static void ng_dumphooks(void); 82 83 #endif /* NETGRAPH_DEBUG */ 84 /* 85 * DEAD versions of the structures. 86 * In order to avoid races, it is sometimes neccesary to point 87 * at SOMETHING even though theoretically, the current entity is 88 * INVALID. Use these to avoid these races. 89 */ 90 struct ng_type ng_deadtype = { 91 NG_ABI_VERSION, 92 "dead", 93 NULL, /* modevent */ 94 NULL, /* constructor */ 95 NULL, /* rcvmsg */ 96 NULL, /* shutdown */ 97 NULL, /* newhook */ 98 NULL, /* findhook */ 99 NULL, /* connect */ 100 NULL, /* rcvdata */ 101 NULL, /* disconnect */ 102 NULL, /* cmdlist */ 103 }; 104 105 struct ng_node ng_deadnode = { 106 "dead", 107 &ng_deadtype, 108 NG_INVALID, 109 1, /* refs */ 110 0, /* numhooks */ 111 NULL, /* private */ 112 0, /* ID */ 113 LIST_HEAD_INITIALIZER(ng_deadnode.hooks), 114 {}, /* all_nodes list entry */ 115 {}, /* id hashtable list entry */ 116 {}, /* workqueue entry */ 117 { 0, 118 {}, /* should never use! (should hang) */ 119 NULL, 120 &ng_deadnode.nd_input_queue.queue, 121 &ng_deadnode 122 }, 123 #ifdef NETGRAPH_DEBUG 124 ND_MAGIC, 125 __FILE__, 126 __LINE__, 127 {NULL} 128 #endif /* NETGRAPH_DEBUG */ 129 }; 130 131 struct ng_hook ng_deadhook = { 132 "dead", 133 NULL, /* private */ 134 HK_INVALID | HK_DEAD, 135 1, /* refs always >= 1 */ 136 &ng_deadhook, /* Peer is self */ 137 &ng_deadnode, /* attached to deadnode */ 138 {}, /* hooks list */ 139 #ifdef NETGRAPH_DEBUG 140 HK_MAGIC, 141 __FILE__, 142 __LINE__, 143 {NULL} 144 #endif /* NETGRAPH_DEBUG */ 145 }; 146 147 /* 148 * END DEAD STRUCTURES 149 */ 150 /* List nodes with unallocated work */ 151 static TAILQ_HEAD(, ng_node) ng_worklist = TAILQ_HEAD_INITIALIZER(ng_worklist); 152 static struct mtx ng_worklist_mtx; 153 154 /* List of installed types */ 155 static LIST_HEAD(, ng_type) ng_typelist; 156 static struct mtx ng_typelist_mtx; 157 158 /* Hash related definitions */ 159 /* XXX Don't need to initialise them because it's a LIST */ 160 #define NG_ID_HASH_SIZE 32 /* most systems wont need even this many */ 161 static LIST_HEAD(, ng_node) ng_ID_hash[NG_ID_HASH_SIZE]; 162 static struct mtx ng_idhash_mtx; 163 /* Method to find a node.. used twice so do it here */ 164 #define NG_IDHASH_FN(ID) ((ID) % (NG_ID_HASH_SIZE)) 165 #define NG_IDHASH_FIND(ID, node) \ 166 do { \ 167 LIST_FOREACH(node, &ng_ID_hash[NG_IDHASH_FN(ID)], \ 168 nd_idnodes) { \ 169 if (NG_NODE_IS_VALID(node) \ 170 && (NG_NODE_ID(node) == ID)) { \ 171 break; \ 172 } \ 173 } \ 174 } while (0) 175 176 /* Mutex that protects the free queue item list */ 177 static volatile item_p ngqfree; /* free ones */ 178 static struct mtx ngq_mtx; 179 180 /* Internal functions */ 181 static int ng_add_hook(node_p node, const char *name, hook_p * hookp); 182 static int ng_generic_msg(node_p here, item_p item, hook_p lasthook); 183 static ng_ID_t ng_decodeidname(const char *name); 184 static int ngb_mod_event(module_t mod, int event, void *data); 185 static void ng_worklist_remove(node_p node); 186 static void ngintr(void); 187 static int ng_apply_item(node_p node, item_p item); 188 static void ng_flush_input_queue(struct ng_queue * ngq); 189 static void ng_setisr(node_p node); 190 static node_p ng_ID2noderef(ng_ID_t ID); 191 static int ng_con_nodes(node_p node, const char *name, node_p node2, 192 const char *name2); 193 static int ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2); 194 static int ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2); 195 static int ng_mkpeer(node_p node, const char *name, 196 const char *name2, char *type); 197 198 /* imported , these used to be externally visible, some may go back */ 199 int ng_bypass(hook_p hook1, hook_p hook2); 200 void ng_destroy_hook(hook_p hook); 201 node_p ng_name2noderef(node_p node, const char *name); 202 int ng_path2noderef(node_p here, const char *path, 203 node_p *dest, hook_p *lasthook); 204 struct ng_type *ng_findtype(const char *type); 205 int ng_make_node(const char *type, node_p *nodepp); 206 int ng_path_parse(char *addr, char **node, char **path, char **hook); 207 void ng_rmnode(node_p node); 208 void ng_unname(node_p node); 209 210 211 /* Our own netgraph malloc type */ 212 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages"); 213 MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures"); 214 MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures"); 215 MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", "netgraph item structures"); 216 MALLOC_DEFINE(M_NETGRAPH_META, "netgraph_meta", "netgraph name storage"); 217 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage"); 218 219 /* Should not be visible outside this file */ 220 221 #define _NG_ALLOC_HOOK(hook) \ 222 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO) 223 #define _NG_ALLOC_NODE(node) \ 224 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO) 225 226 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/ 227 /* 228 * In debug mode: 229 * In an attempt to help track reference count screwups 230 * we do not free objects back to the malloc system, but keep them 231 * in a local cache where we can examine them and keep information safely 232 * after they have been freed. 233 * We use this scheme for nodes and hooks, and to some extent for items. 234 */ 235 static __inline hook_p 236 ng_alloc_hook(void) 237 { 238 hook_p hook; 239 SLIST_ENTRY(ng_hook) temp; 240 mtx_enter(&ng_nodelist_mtx, MTX_DEF); 241 hook = LIST_FIRST(&ng_freehooks); 242 if (hook) { 243 LIST_REMOVE(hook, hk_hooks); 244 bcopy(&hook->hk_all, &temp, sizeof(temp)); 245 bzero(hook, sizeof(struct ng_hook)); 246 bcopy(&temp, &hook->hk_all, sizeof(temp)); 247 mtx_exit(&ng_nodelist_mtx, MTX_DEF); 248 hook->hk_magic = HK_MAGIC; 249 } else { 250 mtx_exit(&ng_nodelist_mtx, MTX_DEF); 251 _NG_ALLOC_HOOK(hook); 252 if (hook) { 253 hook->hk_magic = HK_MAGIC; 254 mtx_enter(&ng_nodelist_mtx, MTX_DEF); 255 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all); 256 mtx_exit(&ng_nodelist_mtx, MTX_DEF); 257 } 258 } 259 return (hook); 260 } 261 262 static __inline node_p 263 ng_alloc_node(void) 264 { 265 node_p node; 266 SLIST_ENTRY(ng_node) temp; 267 mtx_enter(&ng_nodelist_mtx, MTX_DEF); 268 node = LIST_FIRST(&ng_freenodes); 269 if (node) { 270 LIST_REMOVE(node, nd_nodes); 271 bcopy(&node->nd_all, &temp, sizeof(temp)); 272 bzero(node, sizeof(struct ng_node)); 273 bcopy(&temp, &node->nd_all, sizeof(temp)); 274 mtx_exit(&ng_nodelist_mtx, MTX_DEF); 275 node->nd_magic = ND_MAGIC; 276 } else { 277 mtx_exit(&ng_nodelist_mtx, MTX_DEF); 278 _NG_ALLOC_NODE(node); 279 if (node) { 280 node->nd_magic = ND_MAGIC; 281 mtx_enter(&ng_nodelist_mtx, MTX_DEF); 282 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all); 283 mtx_exit(&ng_nodelist_mtx, MTX_DEF); 284 } 285 } 286 return (node); 287 } 288 289 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0) 290 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0) 291 292 293 #define NG_FREE_HOOK(hook) \ 294 do { \ 295 mtx_enter(&ng_nodelist_mtx, MTX_DEF); \ 296 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \ 297 hook->hk_magic = 0; \ 298 mtx_exit(&ng_nodelist_mtx, MTX_DEF); \ 299 } while (0) 300 301 #define NG_FREE_NODE(node) \ 302 do { \ 303 mtx_enter(&ng_nodelist_mtx, MTX_DEF); \ 304 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \ 305 node->nd_magic = 0; \ 306 mtx_exit(&ng_nodelist_mtx, MTX_DEF); \ 307 } while (0) 308 309 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 310 311 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook) 312 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node) 313 314 #define NG_FREE_HOOK(hook) do { FREE((hook), M_NETGRAPH_HOOK); } while (0) 315 #define NG_FREE_NODE(node) do { FREE((node), M_NETGRAPH_NODE); } while (0) 316 317 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 318 319 /* Warning: Generally use NG_FREE_ITEM() instead */ 320 #define NG_FREE_ITEM_REAL(item) do { FREE((item), M_NETGRAPH_ITEM); } while (0) 321 322 323 /* Set this to Debugger("X") to catch all errors as they occur */ 324 #ifndef TRAP_ERROR 325 #define TRAP_ERROR() 326 #endif 327 328 static ng_ID_t nextID = 1; 329 330 #ifdef INVARIANTS 331 #define CHECK_DATA_MBUF(m) do { \ 332 struct mbuf *n; \ 333 int total; \ 334 \ 335 if (((m)->m_flags & M_PKTHDR) == 0) \ 336 panic("%s: !PKTHDR", __FUNCTION__); \ 337 for (total = 0, n = (m); n != NULL; n = n->m_next) \ 338 total += n->m_len; \ 339 if ((m)->m_pkthdr.len != total) { \ 340 panic("%s: %d != %d", \ 341 __FUNCTION__, (m)->m_pkthdr.len, total); \ 342 } \ 343 } while (0) 344 #else 345 #define CHECK_DATA_MBUF(m) 346 #endif 347 348 349 /************************************************************************ 350 Parse type definitions for generic messages 351 ************************************************************************/ 352 353 /* Handy structure parse type defining macro */ 354 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \ 355 static const struct ng_parse_struct_info \ 356 ng_ ## lo ## _type_info = NG_GENERIC_ ## up ## _INFO args; \ 357 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \ 358 &ng_parse_struct_type, \ 359 &ng_ ## lo ## _type_info \ 360 } 361 362 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ()); 363 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ()); 364 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ()); 365 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ()); 366 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ()); 367 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ()); 368 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type)); 369 370 /* Get length of an array when the length is stored as a 32 bit 371 value immediately preceeding the array -- as with struct namelist 372 and struct typelist. */ 373 static int 374 ng_generic_list_getLength(const struct ng_parse_type *type, 375 const u_char *start, const u_char *buf) 376 { 377 return *((const u_int32_t *)(buf - 4)); 378 } 379 380 /* Get length of the array of struct linkinfo inside a struct hooklist */ 381 static int 382 ng_generic_linkinfo_getLength(const struct ng_parse_type *type, 383 const u_char *start, const u_char *buf) 384 { 385 const struct hooklist *hl = (const struct hooklist *)start; 386 387 return hl->nodeinfo.hooks; 388 } 389 390 /* Array type for a variable length array of struct namelist */ 391 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = { 392 &ng_generic_nodeinfo_type, 393 &ng_generic_list_getLength 394 }; 395 static const struct ng_parse_type ng_generic_nodeinfoarray_type = { 396 &ng_parse_array_type, 397 &ng_nodeinfoarray_type_info 398 }; 399 400 /* Array type for a variable length array of struct typelist */ 401 static const struct ng_parse_array_info ng_typeinfoarray_type_info = { 402 &ng_generic_typeinfo_type, 403 &ng_generic_list_getLength 404 }; 405 static const struct ng_parse_type ng_generic_typeinfoarray_type = { 406 &ng_parse_array_type, 407 &ng_typeinfoarray_type_info 408 }; 409 410 /* Array type for array of struct linkinfo in struct hooklist */ 411 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = { 412 &ng_generic_linkinfo_type, 413 &ng_generic_linkinfo_getLength 414 }; 415 static const struct ng_parse_type ng_generic_linkinfo_array_type = { 416 &ng_parse_array_type, 417 &ng_generic_linkinfo_array_type_info 418 }; 419 420 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type)); 421 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST, 422 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type)); 423 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES, 424 (&ng_generic_nodeinfoarray_type)); 425 426 /* List of commands and how to convert arguments to/from ASCII */ 427 static const struct ng_cmdlist ng_generic_cmds[] = { 428 { 429 NGM_GENERIC_COOKIE, 430 NGM_SHUTDOWN, 431 "shutdown", 432 NULL, 433 NULL 434 }, 435 { 436 NGM_GENERIC_COOKIE, 437 NGM_MKPEER, 438 "mkpeer", 439 &ng_generic_mkpeer_type, 440 NULL 441 }, 442 { 443 NGM_GENERIC_COOKIE, 444 NGM_CONNECT, 445 "connect", 446 &ng_generic_connect_type, 447 NULL 448 }, 449 { 450 NGM_GENERIC_COOKIE, 451 NGM_NAME, 452 "name", 453 &ng_generic_name_type, 454 NULL 455 }, 456 { 457 NGM_GENERIC_COOKIE, 458 NGM_RMHOOK, 459 "rmhook", 460 &ng_generic_rmhook_type, 461 NULL 462 }, 463 { 464 NGM_GENERIC_COOKIE, 465 NGM_NODEINFO, 466 "nodeinfo", 467 NULL, 468 &ng_generic_nodeinfo_type 469 }, 470 { 471 NGM_GENERIC_COOKIE, 472 NGM_LISTHOOKS, 473 "listhooks", 474 NULL, 475 &ng_generic_hooklist_type 476 }, 477 { 478 NGM_GENERIC_COOKIE, 479 NGM_LISTNAMES, 480 "listnames", 481 NULL, 482 &ng_generic_listnodes_type /* same as NGM_LISTNODES */ 483 }, 484 { 485 NGM_GENERIC_COOKIE, 486 NGM_LISTNODES, 487 "listnodes", 488 NULL, 489 &ng_generic_listnodes_type 490 }, 491 { 492 NGM_GENERIC_COOKIE, 493 NGM_LISTTYPES, 494 "listtypes", 495 NULL, 496 &ng_generic_typeinfo_type 497 }, 498 { 499 NGM_GENERIC_COOKIE, 500 NGM_TEXT_CONFIG, 501 "textconfig", 502 NULL, 503 &ng_parse_string_type 504 }, 505 { 506 NGM_GENERIC_COOKIE, 507 NGM_TEXT_STATUS, 508 "textstatus", 509 NULL, 510 &ng_parse_string_type 511 }, 512 { 513 NGM_GENERIC_COOKIE, 514 NGM_ASCII2BINARY, 515 "ascii2binary", 516 &ng_parse_ng_mesg_type, 517 &ng_parse_ng_mesg_type 518 }, 519 { 520 NGM_GENERIC_COOKIE, 521 NGM_BINARY2ASCII, 522 "binary2ascii", 523 &ng_parse_ng_mesg_type, 524 &ng_parse_ng_mesg_type 525 }, 526 { 0 } 527 }; 528 529 /************************************************************************ 530 Node routines 531 ************************************************************************/ 532 533 /* 534 * Instantiate a node of the requested type 535 */ 536 int 537 ng_make_node(const char *typename, node_p *nodepp) 538 { 539 struct ng_type *type; 540 int error; 541 542 /* Check that the type makes sense */ 543 if (typename == NULL) { 544 TRAP_ERROR(); 545 return (EINVAL); 546 } 547 548 /* Locate the node type */ 549 if ((type = ng_findtype(typename)) == NULL) { 550 char filename[NG_TYPELEN + 4]; 551 linker_file_t lf; 552 int error; 553 554 /* Not found, try to load it as a loadable module */ 555 snprintf(filename, sizeof(filename), "ng_%s", typename); 556 error = linker_load_file(filename, &lf); 557 if (error != 0) 558 return (error); 559 lf->userrefs++; /* pretend loaded by the syscall */ 560 561 /* Try again, as now the type should have linked itself in */ 562 if ((type = ng_findtype(typename)) == NULL) 563 return (ENXIO); 564 } 565 566 /* 567 * If we have a constructor, then make the node and 568 * call the constructor to do type specific initialisation. 569 */ 570 if (type->constructor != NULL) { 571 if ((error = ng_make_node_common(type, nodepp)) == 0) { 572 if ((error = ((*type->constructor)(*nodepp)) != 0)) { 573 NG_NODE_UNREF(*nodepp); 574 } 575 } 576 } else { 577 /* 578 * Node has no constructor. We cannot ask for one 579 * to be made. It must be brought into existance by 580 * some external agency. The external agency should 581 * call ng_make_node_common() directly to get the 582 * netgraph part initialised. 583 */ 584 TRAP_ERROR(); 585 error = EINVAL; 586 } 587 return (error); 588 } 589 590 /* 591 * Generic node creation. Called by node initialisation for externally 592 * instantiated nodes (e.g. hardware, sockets, etc ). 593 * The returned node has a reference count of 1. 594 */ 595 int 596 ng_make_node_common(struct ng_type *type, node_p *nodepp) 597 { 598 node_p node; 599 600 /* Require the node type to have been already installed */ 601 if (ng_findtype(type->name) == NULL) { 602 TRAP_ERROR(); 603 return (EINVAL); 604 } 605 606 /* Make a node and try attach it to the type */ 607 NG_ALLOC_NODE(node); 608 if (node == NULL) { 609 TRAP_ERROR(); 610 return (ENOMEM); 611 } 612 node->nd_type = type; 613 NG_NODE_REF(node); /* note reference */ 614 type->refs++; 615 616 mtx_init(&node->nd_input_queue.q_mtx, "netgraph node mutex", 0); 617 node->nd_input_queue.queue = NULL; 618 node->nd_input_queue.last = &node->nd_input_queue.queue; 619 node->nd_input_queue.q_flags = 0; 620 node->nd_input_queue.q_node = node; 621 622 /* Initialize hook list for new node */ 623 LIST_INIT(&node->nd_hooks); 624 625 /* Link us into the node linked list */ 626 mtx_enter(&ng_nodelist_mtx, MTX_DEF); 627 LIST_INSERT_HEAD(&ng_nodelist, node, nd_nodes); 628 mtx_exit(&ng_nodelist_mtx, MTX_DEF); 629 630 631 /* get an ID and put us in the hash chain */ 632 mtx_enter(&ng_idhash_mtx, MTX_DEF); 633 for (;;) { /* wrap protection, even if silly */ 634 node_p node2 = NULL; 635 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */ 636 637 /* Is there a problem with the new number? */ 638 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */ 639 if ((node->nd_ID != 0) && (node2 == NULL)) { 640 break; 641 } 642 } 643 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)], 644 node, nd_idnodes); 645 mtx_exit(&ng_idhash_mtx, MTX_DEF); 646 647 /* Done */ 648 *nodepp = node; 649 return (0); 650 } 651 652 /* 653 * Forceably start the shutdown process on a node. Either call 654 * it's shutdown method, or do the default shutdown if there is 655 * no type-specific method. 656 * 657 * We can only be called form a shutdown message, so we know we have 658 * a writer lock, and therefore exclusive access. It also means 659 * that we should not be on the work queue, but we check anyhow. 660 * 661 * Persistent node types must have a type-specific method which 662 * Allocates a new node in which case, this one is irretrievably going away, 663 * or cleans up anything it needs, and just makes the node valid again, 664 * in which case we allow the node to survive. 665 * 666 * XXX We need to think of how to tell a persistant node that we 667 * REALLY need to go away because the hardware has gone or we 668 * are rebooting.... etc. 669 */ 670 void 671 ng_rmnode(node_p node) 672 { 673 hook_p hook; 674 675 /* Check if it's already shutting down */ 676 if ((node->nd_flags & NG_CLOSING) != 0) 677 return; 678 679 /* Add an extra reference so it doesn't go away during this */ 680 NG_NODE_REF(node); 681 682 /* 683 * Mark it invalid so any newcomers know not to try use it 684 * Also add our own mark so we can't recurse 685 * note that NG_INVALID does not do this as it's also set during 686 * creation 687 */ 688 node->nd_flags |= NG_INVALID|NG_CLOSING; 689 690 /* Notify all remaining connected nodes to disconnect */ 691 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL) 692 ng_destroy_hook(hook); 693 694 /* 695 * Drain the input queue forceably. 696 * it has no hooks so what's it going to do, bleed on someone? 697 * Theoretically we came here from a queue entry that was added 698 * Just before the queue was closed, so it should be empty anyway. 699 */ 700 ng_flush_input_queue(&node->nd_input_queue); 701 702 /* 703 * Take us off the work queue if we are there. 704 * We definatly have no work to be done. 705 */ 706 ng_worklist_remove(node); 707 708 /* Ask the type if it has anything to do in this case */ 709 if (node->nd_type && node->nd_type->shutdown) { 710 (*node->nd_type->shutdown)(node); 711 } else { /* do the default thing */ 712 NG_NODE_UNREF(node); 713 } 714 if (NG_NODE_IS_VALID(node)) { 715 /* 716 * Well, blow me down if the node code hasn't declared 717 * that it doesn't want to die. 718 * Presumably it is a persistant node. 719 * XXX we need a way to tell the node 720 * "No, really.. the hardware's going away.. REALLY die" 721 * We need a way 722 */ 723 return; 724 } 725 726 ng_unname(node); /* basically a NOP these days */ 727 728 /* 729 * Remove extra reference, possibly the last 730 * Possible other holders of references may include 731 * timeout callouts, but theoretically the node's supposed to 732 * have cancelled them. Possibly hardware dependencies may 733 * force a driver to 'linger' with a reference. 734 */ 735 NG_NODE_UNREF(node); 736 } 737 738 /* 739 * Remove a reference to the node, possibly the last 740 */ 741 void 742 ng_unref_node(node_p node) 743 { 744 int v; 745 746 if (node == &ng_deadnode) { 747 return; 748 } 749 750 do { 751 v = node->nd_refs; 752 } while (! atomic_cmpset_int(&node->nd_refs, v, v - 1)); 753 754 if (v == 1) { /* we were the last */ 755 756 mtx_enter(&ng_nodelist_mtx, MTX_DEF); 757 node->nd_type->refs--; /* XXX maybe should get types lock? */ 758 LIST_REMOVE(node, nd_nodes); 759 mtx_exit(&ng_nodelist_mtx, MTX_DEF); 760 761 mtx_enter(&ng_idhash_mtx, MTX_DEF); 762 LIST_REMOVE(node, nd_idnodes); 763 mtx_exit(&ng_idhash_mtx, MTX_DEF); 764 765 mtx_destroy(&node->nd_input_queue.q_mtx); 766 NG_FREE_NODE(node); 767 } 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_enter(&ng_idhash_mtx, MTX_DEF); 778 NG_IDHASH_FIND(ID, node); 779 if(node) 780 NG_NODE_REF(node); 781 mtx_exit(&ng_idhash_mtx, MTX_DEF); 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_NODELEN + 1; 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 strncpy(NG_NODE_NAME(node), name, NG_NODELEN); 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_enter(&ng_nodelist_mtx, MTX_DEF); 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_exit(&ng_nodelist_mtx, MTX_DEF); 869 return (node); 870 } 871 872 /* 873 * Decode a 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 */ 905 void 906 ng_unname(node_p node) 907 { 908 bzero(NG_NODE_NAME(node), NG_NODELEN); 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 strncpy(NG_HOOK_NAME(hook), name, NG_HOOKLEN); 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 = NG_HOOK_PEER(hook); 1044 node_p node = NG_HOOK_NODE(hook); 1045 1046 if (hook == &ng_deadhook) { /* better safe than sorry */ 1047 printf("ng_destroy_hook called on deadhook\n"); 1048 return; 1049 } 1050 hook->hk_flags |= HK_INVALID; /* as soon as possible */ 1051 if (peer && (peer != &ng_deadhook)) { 1052 /* 1053 * Set the peer to point to ng_deadhook 1054 * from this moment on we are effectively independent it. 1055 * send it an rmhook message of it's own. 1056 */ 1057 peer->hk_peer = &ng_deadhook; /* They no longer know us */ 1058 hook->hk_peer = &ng_deadhook; /* Nor us, them */ 1059 if (NG_HOOK_NODE(peer) == &ng_deadnode) { 1060 /* 1061 * If it's already divorced from a node, 1062 * just free it. 1063 */ 1064 /* nothing */ 1065 } else { 1066 ng_rmhook_self(peer); /* Send it a surprise */ 1067 } 1068 NG_HOOK_UNREF(peer); /* account for peer link */ 1069 NG_HOOK_UNREF(hook); /* account for peer link */ 1070 } 1071 1072 /* 1073 * Remove the hook from the node's list to avoid possible recursion 1074 * in case the disconnection results in node shutdown. 1075 */ 1076 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */ 1077 return; 1078 } 1079 LIST_REMOVE(hook, hk_hooks); 1080 node->nd_numhooks--; 1081 if (node->nd_type->disconnect) { 1082 /* 1083 * The type handler may elect to destroy the node so don't 1084 * trust its existance after this point. (except 1085 * that we still hold a reference on it. (which we 1086 * inherrited from the hook we are destroying) 1087 */ 1088 (*node->nd_type->disconnect) (hook); 1089 } 1090 1091 /* 1092 * Note that because we will point to ng_deadnode, the original node 1093 * is not decremented automatically so we do that manually. 1094 */ 1095 _NG_HOOK_NODE(hook) = &ng_deadnode; 1096 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */ 1097 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */ 1098 } 1099 1100 /* 1101 * Take two hooks on a node and merge the connection so that the given node 1102 * is effectively bypassed. 1103 */ 1104 int 1105 ng_bypass(hook_p hook1, hook_p hook2) 1106 { 1107 if (hook1->hk_node != hook2->hk_node) { 1108 TRAP_ERROR(); 1109 return (EINVAL); 1110 } 1111 hook1->hk_peer->hk_peer = hook2->hk_peer; 1112 hook2->hk_peer->hk_peer = hook1->hk_peer; 1113 1114 hook1->hk_peer = &ng_deadhook; 1115 hook2->hk_peer = &ng_deadhook; 1116 1117 /* XXX If we ever cache methods on hooks update them as well */ 1118 ng_destroy_hook(hook1); 1119 ng_destroy_hook(hook2); 1120 return (0); 1121 } 1122 1123 /* 1124 * Install a new netgraph type 1125 */ 1126 int 1127 ng_newtype(struct ng_type *tp) 1128 { 1129 const size_t namelen = strlen(tp->name); 1130 1131 /* Check version and type name fields */ 1132 if ((tp->version != NG_ABI_VERSION) 1133 || (namelen == 0) 1134 || (namelen > NG_TYPELEN)) { 1135 TRAP_ERROR(); 1136 return (EINVAL); 1137 } 1138 1139 /* Check for name collision */ 1140 if (ng_findtype(tp->name) != NULL) { 1141 TRAP_ERROR(); 1142 return (EEXIST); 1143 } 1144 1145 tp->refs = 0; 1146 1147 /* Link in new type */ 1148 mtx_enter(&ng_typelist_mtx, MTX_DEF); 1149 LIST_INSERT_HEAD(&ng_typelist, tp, types); 1150 mtx_exit(&ng_typelist_mtx, MTX_DEF); 1151 return (0); 1152 } 1153 1154 /* 1155 * Look for a type of the name given 1156 */ 1157 struct ng_type * 1158 ng_findtype(const char *typename) 1159 { 1160 struct ng_type *type; 1161 1162 mtx_enter(&ng_typelist_mtx, MTX_DEF); 1163 LIST_FOREACH(type, &ng_typelist, types) { 1164 if (strcmp(type->name, typename) == 0) 1165 break; 1166 } 1167 mtx_exit(&ng_typelist_mtx, MTX_DEF); 1168 return (type); 1169 } 1170 1171 /************************************************************************ 1172 Composite routines 1173 ************************************************************************/ 1174 /* 1175 * Connect two nodes using the specified hooks, using queued functions. 1176 */ 1177 static int 1178 ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2) 1179 { 1180 int error = 0; 1181 1182 /* 1183 * When we run, we know that the node 'node' is locked for us. 1184 * Our caller has a reference on the hook. 1185 * Our caller has a reference on the node. 1186 * (In this case our caller is ng_apply_item() ). 1187 * The peer hook has a reference on the hook. 1188 */ 1189 if (NG_HOOK_NODE(hook) == &ng_deadnode) { 1190 /* 1191 * The node must have been freed again since we last visited 1192 * here. ng_destry_hook() has this effect but nothing else does. 1193 * We should just release our references and 1194 * free anything we can think of. 1195 * Since we know it's been destroyed, and it's our caller 1196 * that holds the references, just return. 1197 */ 1198 return (0); 1199 } 1200 if (hook->hk_node->nd_type->connect) { 1201 if ((error = (*hook->hk_node->nd_type->connect) (hook))) { 1202 ng_destroy_hook(hook); /* also zaps peer */ 1203 return (error); 1204 } 1205 } 1206 /* 1207 * XXX this is wrong for SMP. Possibly we need 1208 * to separate out 'create' and 'invalid' flags. 1209 * should only set flags on hooks we have locked under our node. 1210 */ 1211 hook->hk_flags &= ~HK_INVALID; 1212 return (error); 1213 } 1214 1215 static int 1216 ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2) 1217 { 1218 int error = 0; 1219 1220 /* 1221 * When we run, we know that the node 'node' is locked for us. 1222 * Our caller has a reference on the hook. 1223 * Our caller has a reference on the node. 1224 * (In this case our caller is ng_apply_item() ). 1225 * The peer hook has a reference on the hook. 1226 * our node pointer points to the 'dead' node. 1227 * First check the hook name is unique. 1228 */ 1229 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) { 1230 TRAP_ERROR(); 1231 ng_destroy_hook(hook); /* should destroy peer too */ 1232 return (EEXIST); 1233 } 1234 /* 1235 * Check if the node type code has something to say about it 1236 * If it fails, the unref of the hook will also unref the attached node, 1237 * however since that node is 'ng_deadnode' this will do nothing. 1238 * The peer hook will also be destroyed. 1239 */ 1240 if (node->nd_type->newhook != NULL) { 1241 if ((error = 1242 (*node->nd_type->newhook)(node, hook, hook->hk_name))) { 1243 ng_destroy_hook(hook); /* should destroy peer too */ 1244 return (error); 1245 } 1246 } 1247 1248 /* 1249 * The 'type' agrees so far, so go ahead and link it in. 1250 * We'll ask again later when we actually connect the hooks. 1251 */ 1252 hook->hk_node = node; /* just overwrite ng_deadnode */ 1253 NG_NODE_REF(node); /* each hook counts as a reference */ 1254 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1255 node->nd_numhooks++; 1256 NG_HOOK_REF(hook); /* one for the node */ 1257 1258 /* 1259 * We now have a symetrical situation, where both hooks have been 1260 * linked to theur nodes, the newhook methods have been called 1261 * And the references are all correct. The hooks are still marked 1262 * as invalid, as we have not called the 'connect' methods 1263 * yet. 1264 * We can call the local one immediatly as we have the 1265 * node locked, but we need to queue the remote one. 1266 */ 1267 if (hook->hk_node->nd_type->connect) { 1268 if ((error = (*hook->hk_node->nd_type->connect) (hook))) { 1269 ng_destroy_hook(hook); /* also zaps peer */ 1270 return (error); 1271 } 1272 } 1273 error = ng_send_fn(hook->hk_peer->hk_node, hook->hk_peer, 1274 &ng_con_part3, arg1, arg2); 1275 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */ 1276 return (error); 1277 } 1278 1279 /* 1280 * Connect this node with another node. We assume that this node is 1281 * currently locked, as we are only called from an NGM_CONNECT message. 1282 */ 1283 static int 1284 ng_con_nodes(node_p node, const char *name, node_p node2, const char *name2) 1285 { 1286 int error; 1287 hook_p hook; 1288 hook_p hook2; 1289 1290 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */ 1291 return (error); 1292 /* Allocate the other hook and link it up */ 1293 NG_ALLOC_HOOK(hook2); 1294 if (hook == NULL) { 1295 TRAP_ERROR(); 1296 ng_destroy_hook(hook); /* XXX check ref counts so far */ 1297 NG_HOOK_UNREF(hook); /* including our ref */ 1298 return (ENOMEM); 1299 } 1300 hook2->hk_refs = 1; /* start with a reference for us. */ 1301 hook2->hk_flags = HK_INVALID; 1302 hook2->hk_peer = hook; /* Link the two together */ 1303 hook->hk_peer = hook2; 1304 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/ 1305 NG_HOOK_REF(hook2); 1306 hook2->hk_node = &ng_deadnode; 1307 strncpy(NG_HOOK_NAME(hook2), name2, NG_HOOKLEN); 1308 1309 /* 1310 * Queue the function above. 1311 * Procesing continues in that function in the lock context of 1312 * the other node. 1313 */ 1314 error = ng_send_fn(node2, hook2, &ng_con_part2, NULL, 0); 1315 1316 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */ 1317 NG_HOOK_UNREF(hook2); 1318 return (error); 1319 } 1320 1321 /* 1322 * Make a peer and connect. 1323 * We assume that the local node is locked. 1324 * The new node probably doesn't need a lock until 1325 * it has a hook, because it cannot really have any work until then, 1326 * but we should think about it a bit more. 1327 * 1328 * The problem may come if the other node also fires up 1329 * some hardware or a timer or some other source of activation, 1330 * also it may already get a command msg via it's ID. 1331 * 1332 * We could use the same method as ng_con_nodes() but we'd have 1333 * to add ability to remove the node when failing. (Not hard, just 1334 * make arg1 point to the node to remove). 1335 * Unless of course we just ignore failure to connect and leave 1336 * an unconnected node? 1337 */ 1338 static int 1339 ng_mkpeer(node_p node, const char *name, const char *name2, char *type) 1340 { 1341 node_p node2; 1342 hook_p hook1; 1343 hook_p hook2; 1344 int error; 1345 1346 if ((error = ng_make_node(type, &node2))) { 1347 return (error); 1348 } 1349 1350 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */ 1351 ng_rmnode(node2); 1352 return (error); 1353 } 1354 1355 if ((error = ng_add_hook(node2, name2, &hook2))) { 1356 ng_rmnode(node2); 1357 ng_destroy_hook(hook1); 1358 NG_HOOK_UNREF(hook1); 1359 return (error); 1360 } 1361 1362 /* 1363 * Actually link the two hooks together. 1364 */ 1365 hook1->hk_peer = hook2; 1366 hook2->hk_peer = hook1; 1367 1368 /* Each hook is referenced by the other */ 1369 NG_HOOK_REF(hook1); 1370 NG_HOOK_REF(hook2); 1371 1372 /* Give each node the opportunity to veto the pending connection */ 1373 if (hook1->hk_node->nd_type->connect) { 1374 error = (*hook1->hk_node->nd_type->connect) (hook1); 1375 } 1376 1377 if ((error == 0) && hook2->hk_node->nd_type->connect) { 1378 error = (*hook2->hk_node->nd_type->connect) (hook2); 1379 1380 } 1381 1382 /* 1383 * drop the references we were holding on the two hooks. 1384 */ 1385 if (error) { 1386 ng_destroy_hook(hook2); /* also zaps hook1 */ 1387 ng_rmnode(node2); 1388 } else { 1389 /* As a last act, allow the hooks to be used */ 1390 hook1->hk_flags &= ~HK_INVALID; 1391 hook2->hk_flags &= ~HK_INVALID; 1392 } 1393 NG_HOOK_UNREF(hook1); 1394 NG_HOOK_UNREF(hook2); 1395 return (error); 1396 } 1397 1398 /************************************************************************ 1399 Utility routines to send self messages 1400 ************************************************************************/ 1401 /* 1402 * Static version of shutdown message. we don't want to need resources 1403 * to shut down (we may be doing it to release resources because we ran out. 1404 */ 1405 static struct ng_mesg ng_msg_shutdown = { 1406 {NG_VERSION, /* u_char */ 1407 0, /* u_char spare */ 1408 0, /* u_int16_t arglen */ 1409 NGF_STATIC, /* u_int32_t flags */ 1410 0, /* u_int32_t token */ 1411 NGM_GENERIC_COOKIE, /* u_int32_t */ 1412 NGM_SHUTDOWN, /* u_int32_t */ 1413 "shutdown"} /* u_char[16] */ 1414 }; 1415 1416 int 1417 ng_rmnode_self(node_p here) 1418 { 1419 item_p item; 1420 struct ng_mesg *msg; 1421 1422 /* 1423 * Use the static version to avoid needing 1424 * memory allocation to succeed. 1425 * The message is never written to and always the same. 1426 */ 1427 msg = &ng_msg_shutdown; 1428 1429 /* 1430 * Try get a queue item to send it with. 1431 * Hopefully since it has a reserve, we can get one. 1432 * If we can't we are screwed anyhow. 1433 * Increase the chances by flushing our queue first. 1434 * We may free an item, (if we were the hog). 1435 * Work in progress is allowed to complete. 1436 * We also pretty much ensure that we come straight 1437 * back in to do the shutdown. It may be a good idea 1438 * to hold a reference actually to stop it from all 1439 * going up in smoke. 1440 */ 1441 /* ng_flush_input_queue(&here->nd_input_queue); will mask problem */ 1442 item = ng_package_msg_self(here, NULL, msg); 1443 if (item == NULL) { /* it would have freed the msg except static */ 1444 /* try again after flushing our queue */ 1445 ng_flush_input_queue(&here->nd_input_queue); 1446 item = ng_package_msg_self(here, NULL, msg); 1447 if (item == NULL) { 1448 printf("failed to free node 0x%x\n", ng_node2ID(here)); 1449 return (ENOMEM); 1450 } 1451 } 1452 return (ng_snd_item(item, 0)); 1453 } 1454 1455 static int 1456 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2) 1457 { 1458 ng_destroy_hook(hook); 1459 return (0); 1460 } 1461 1462 int 1463 ng_rmhook_self(hook_p hook) 1464 { 1465 int error; 1466 node_p node = NG_HOOK_NODE(hook); 1467 1468 if (node == &ng_deadnode) 1469 return (0); 1470 1471 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0); 1472 return (error); 1473 } 1474 1475 /*********************************************************************** 1476 * Parse and verify a string of the form: <NODE:><PATH> 1477 * 1478 * Such a string can refer to a specific node or a specific hook 1479 * on a specific node, depending on how you look at it. In the 1480 * latter case, the PATH component must not end in a dot. 1481 * 1482 * Both <NODE:> and <PATH> are optional. The <PATH> is a string 1483 * of hook names separated by dots. This breaks out the original 1484 * string, setting *nodep to "NODE" (or NULL if none) and *pathp 1485 * to "PATH" (or NULL if degenerate). Also, *hookp will point to 1486 * the final hook component of <PATH>, if any, otherwise NULL. 1487 * 1488 * This returns -1 if the path is malformed. The char ** are optional. 1489 ***********************************************************************/ 1490 int 1491 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp) 1492 { 1493 char *node, *path, *hook; 1494 int k; 1495 1496 /* 1497 * Extract absolute NODE, if any 1498 */ 1499 for (path = addr; *path && *path != ':'; path++); 1500 if (*path) { 1501 node = addr; /* Here's the NODE */ 1502 *path++ = '\0'; /* Here's the PATH */ 1503 1504 /* Node name must not be empty */ 1505 if (!*node) 1506 return -1; 1507 1508 /* A name of "." is OK; otherwise '.' not allowed */ 1509 if (strcmp(node, ".") != 0) { 1510 for (k = 0; node[k]; k++) 1511 if (node[k] == '.') 1512 return -1; 1513 } 1514 } else { 1515 node = NULL; /* No absolute NODE */ 1516 path = addr; /* Here's the PATH */ 1517 } 1518 1519 /* Snoop for illegal characters in PATH */ 1520 for (k = 0; path[k]; k++) 1521 if (path[k] == ':') 1522 return -1; 1523 1524 /* Check for no repeated dots in PATH */ 1525 for (k = 0; path[k]; k++) 1526 if (path[k] == '.' && path[k + 1] == '.') 1527 return -1; 1528 1529 /* Remove extra (degenerate) dots from beginning or end of PATH */ 1530 if (path[0] == '.') 1531 path++; 1532 if (*path && path[strlen(path) - 1] == '.') 1533 path[strlen(path) - 1] = 0; 1534 1535 /* If PATH has a dot, then we're not talking about a hook */ 1536 if (*path) { 1537 for (hook = path, k = 0; path[k]; k++) 1538 if (path[k] == '.') { 1539 hook = NULL; 1540 break; 1541 } 1542 } else 1543 path = hook = NULL; 1544 1545 /* Done */ 1546 if (nodep) 1547 *nodep = node; 1548 if (pathp) 1549 *pathp = path; 1550 if (hookp) 1551 *hookp = hook; 1552 return (0); 1553 } 1554 1555 /* 1556 * Given a path, which may be absolute or relative, and a starting node, 1557 * return the destination node. 1558 */ 1559 int 1560 ng_path2noderef(node_p here, const char *address, 1561 node_p *destp, hook_p *lasthook) 1562 { 1563 char fullpath[NG_PATHLEN + 1]; 1564 char *nodename, *path, pbuf[2]; 1565 node_p node, oldnode; 1566 char *cp; 1567 hook_p hook = NULL; 1568 1569 /* Initialize */ 1570 if (destp == NULL) { 1571 TRAP_ERROR(); 1572 return EINVAL; 1573 } 1574 *destp = NULL; 1575 1576 /* Make a writable copy of address for ng_path_parse() */ 1577 strncpy(fullpath, address, sizeof(fullpath) - 1); 1578 fullpath[sizeof(fullpath) - 1] = '\0'; 1579 1580 /* Parse out node and sequence of hooks */ 1581 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) { 1582 TRAP_ERROR(); 1583 return EINVAL; 1584 } 1585 if (path == NULL) { 1586 pbuf[0] = '.'; /* Needs to be writable */ 1587 pbuf[1] = '\0'; 1588 path = pbuf; 1589 } 1590 1591 /* 1592 * For an absolute address, jump to the starting node. 1593 * Note that this holds a reference on the node for us. 1594 * Don't forget to drop the reference if we don't need it. 1595 */ 1596 if (nodename) { 1597 node = ng_name2noderef(here, nodename); 1598 if (node == NULL) { 1599 TRAP_ERROR(); 1600 return (ENOENT); 1601 } 1602 } else { 1603 if (here == NULL) { 1604 TRAP_ERROR(); 1605 return (EINVAL); 1606 } 1607 node = here; 1608 NG_NODE_REF(node); 1609 } 1610 1611 /* 1612 * Now follow the sequence of hooks 1613 * XXX 1614 * We actually cannot guarantee that the sequence 1615 * is not being demolished as we crawl along it 1616 * without extra-ordinary locking etc. 1617 * So this is a bit dodgy to say the least. 1618 * We can probably hold up some things by holding 1619 * the nodelist mutex for the time of this 1620 * crawl if we wanted.. At least that way we wouldn't have to 1621 * worry about the nodes dissappearing, but the hooks would still 1622 * be a problem. 1623 */ 1624 for (cp = path; node != NULL && *cp != '\0'; ) { 1625 char *segment; 1626 1627 /* 1628 * Break out the next path segment. Replace the dot we just 1629 * found with a NUL; "cp" points to the next segment (or the 1630 * NUL at the end). 1631 */ 1632 for (segment = cp; *cp != '\0'; cp++) { 1633 if (*cp == '.') { 1634 *cp++ = '\0'; 1635 break; 1636 } 1637 } 1638 1639 /* Empty segment */ 1640 if (*segment == '\0') 1641 continue; 1642 1643 /* We have a segment, so look for a hook by that name */ 1644 hook = ng_findhook(node, segment); 1645 1646 /* Can't get there from here... */ 1647 if (hook == NULL 1648 || NG_HOOK_PEER(hook) == NULL 1649 || NG_HOOK_NOT_VALID(hook) 1650 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) { 1651 TRAP_ERROR(); 1652 NG_NODE_UNREF(node); 1653 #if 0 1654 printf("hooknotvalid %s %s %d %d %d %d ", 1655 path, 1656 segment, 1657 hook == NULL, 1658 NG_HOOK_PEER(hook) == NULL, 1659 NG_HOOK_NOT_VALID(hook), 1660 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))); 1661 #endif 1662 return (ENOENT); 1663 } 1664 1665 /* 1666 * Hop on over to the next node 1667 * XXX 1668 * Big race conditions here as hooks and nodes go away 1669 * *** Idea.. store an ng_ID_t in each hook and use that 1670 * instead of the direct hook in this crawl? 1671 */ 1672 oldnode = node; 1673 if ((node = NG_PEER_NODE(hook))) 1674 NG_NODE_REF(node); /* XXX RACE */ 1675 NG_NODE_UNREF(oldnode); /* XXX another race */ 1676 if (NG_NODE_NOT_VALID(node)) { 1677 NG_NODE_UNREF(node); /* XXX more races */ 1678 node = NULL; 1679 } 1680 } 1681 1682 /* If node somehow missing, fail here (probably this is not needed) */ 1683 if (node == NULL) { 1684 TRAP_ERROR(); 1685 return (ENXIO); 1686 } 1687 1688 /* Done */ 1689 *destp = node; 1690 if (lasthook != NULL) 1691 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL); 1692 return (0); 1693 } 1694 1695 /***************************************************************\ 1696 * Input queue handling. 1697 * All activities are submitted to the node via the input queue 1698 * which implements a multiple-reader/single-writer gate. 1699 * Items which cannot be handled immeditly are queued. 1700 * 1701 * read-write queue locking inline functions * 1702 \***************************************************************/ 1703 1704 static __inline item_p ng_dequeue(struct ng_queue * ngq); 1705 static __inline item_p ng_acquire_read(struct ng_queue * ngq, 1706 item_p item); 1707 static __inline item_p ng_acquire_write(struct ng_queue * ngq, 1708 item_p item); 1709 static __inline void ng_leave_read(struct ng_queue * ngq); 1710 static __inline void ng_leave_write(struct ng_queue * ngq); 1711 static __inline void ng_queue_rw(struct ng_queue * ngq, 1712 item_p item, int rw); 1713 1714 /* 1715 * Definition of the bits fields in the ng_queue flag word. 1716 * Defined here rather than in netgraph.h because no-one should fiddle 1717 * with them. 1718 * 1719 * The ordering here is important! don't shuffle these. If you add 1720 * READ_PENDING to the word when it has READ_PENDING already set, you 1721 * generate a carry into the reader count, this you atomically add a reader, 1722 * and remove the pending reader count! Similarly for the pending writer 1723 * flag, adding WRITE_PENDING generates a carry and sets the WRITER_ACTIVE 1724 * flag, while clearing WRITE_PENDING. When 'SINGLE_THREAD_ONLY' is set, then 1725 * it is only permitted to do WRITER operations. Reader operations will 1726 * result in errors. 1727 * But that "hack" is unnecessary: "cpp" can do the math for us! 1728 */ 1729 /*- 1730 Safety Barrier--------+ (adjustable to suit taste) (not used yet) 1731 | 1732 V 1733 +-------+-------+-------+-------+-------+-------+-------+-------+ 1734 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1735 |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |R|A|W|S| 1736 | | | | | | | | | | | | | | | | | | | | | | | | | | | | |P|W|P|T| 1737 +-------+-------+-------+-------+-------+-------+-------+-------+ 1738 \_________________________ ____________________________/ | | | | 1739 V | | | | 1740 [active reader count] | | | | 1741 | | | | 1742 Read Pending ------------------------------------+ | | | 1743 | | | 1744 Active Writer -------------------------------------+ | | 1745 | | 1746 Write Pending ---------------------------------------+ | 1747 | 1748 Single Threading Only ---------------------------------+ 1749 */ 1750 #define SINGLE_THREAD_ONLY 0x00000001 /* if set, even reads single thread */ 1751 #define WRITE_PENDING 0x00000002 1752 #define WRITER_ACTIVE 0x00000004 1753 #define READ_PENDING 0x00000008 1754 #define READER_INCREMENT 0x00000010 1755 #define READER_MASK 0xfffffff0 /* Not valid if WRITER_ACTIVE is set */ 1756 #define SAFETY_BARRIER 0x00100000 /* 64K items queued should be enough */ 1757 /* 1758 * Taking into account the current state of the queue and node, possibly take 1759 * the next entry off the queue and return it. Return NULL if there was 1760 * nothing we could return, either because there really was nothing there, or 1761 * because the node was in a state where it cannot yet process the next item 1762 * on the queue. 1763 * 1764 * This MUST MUST MUST be called with the mutex held. 1765 */ 1766 static __inline item_p 1767 ng_dequeue(struct ng_queue *ngq) 1768 { 1769 item_p item; 1770 u_int add_arg; 1771 /* 1772 * If there is a writer, then the answer is "no". Everything else 1773 * stops when there is a WRITER. 1774 */ 1775 if (ngq->q_flags & WRITER_ACTIVE) { 1776 return (NULL); 1777 } 1778 /* Now take a look at what's on the queue and what's running */ 1779 if ((ngq->q_flags & ~(READER_MASK | SINGLE_THREAD_ONLY)) == READ_PENDING) { 1780 /* 1781 * It was a reader and we have no write active. We don't care 1782 * how many readers are already active. Adjust the count for 1783 * the item we are about to dequeue. Adding READ_PENDING to 1784 * the exisiting READ_PENDING clears it and generates a carry 1785 * into the reader count. 1786 */ 1787 add_arg = READ_PENDING; 1788 } else if ((ngq->q_flags & ~SINGLE_THREAD_ONLY) == WRITE_PENDING) { 1789 /* 1790 * There is a pending write, no readers and no active writer. 1791 * This means we can go ahead with the pending writer. Note 1792 * the fact that we now have a writer, ready for when we take 1793 * it off the queue. 1794 * 1795 * We don't need to worry about a possible collision with the 1796 * fasttrack reader. 1797 * 1798 * The fasttrack thread may take a long time to discover that we 1799 * are running so we would have an inconsistent state in the 1800 * flags for a while. Since we ignore the reader count 1801 * entirely when the WRITER_ACTIVE flag is set, this should 1802 * not matter (in fact it is defined that way). If it tests 1803 * the flag before this operation, the WRITE_PENDING flag 1804 * will make it fail, and if it tests it later, the 1805 * ACTIVE_WRITER flag will do the same. If it is SO slow that 1806 * we have actually completed the operation, and neither flag 1807 * is set (nor the READ_PENDING) by the time that it tests 1808 * the flags, then it is actually ok for it to continue. If 1809 * it completes and we've finished and the read pending is 1810 * set it still fails. 1811 * 1812 * So we can just ignore it, as long as we can ensure that the 1813 * transition from WRITE_PENDING state to the WRITER_ACTIVE 1814 * state is atomic. 1815 * 1816 * After failing, first it will be held back by the mutex, then 1817 * when it can proceed, it will queue its request, then it 1818 * would arrive at this function. Usually it will have to 1819 * leave empty handed because the ACTIVE WRITER bit wil be 1820 * set. 1821 */ 1822 /* 1823 * Adjust the flags for the item we are about to dequeue. 1824 * Adding WRITE_PENDING to the exisiting WRITE_PENDING clears 1825 * it and generates a carry into the WRITER_ACTIVE flag, all 1826 * atomically. 1827 */ 1828 add_arg = WRITE_PENDING; 1829 /* 1830 * We want to write "active writer, no readers " Now go make 1831 * it true. In fact there may be a number in the readers 1832 * count but we know it is not true and will be fixed soon. 1833 * We will fix the flags for the next pending entry in a 1834 * moment. 1835 */ 1836 } else { 1837 /* 1838 * We can't dequeue anything.. return and say so. Probably we 1839 * have a write pending and the readers count is non zero. If 1840 * we got here because a reader hit us just at the wrong 1841 * moment with the fasttrack code, and put us in a strange 1842 * state, then it will be through in just a moment, (as soon 1843 * as we release the mutex) and keep things moving. 1844 */ 1845 return (0); 1846 } 1847 1848 /* 1849 * Now we dequeue the request (whatever it may be) and correct the 1850 * pending flags and the next and last pointers. 1851 */ 1852 item = ngq->queue; 1853 ngq->queue = item->el_next; 1854 if (ngq->last == &(item->el_next)) { 1855 /* 1856 * that was the last entry in the queue so set the 'last 1857 * pointer up correctly and make sure the pending flags are 1858 * clear. 1859 */ 1860 ngq->last = &(ngq->queue); 1861 /* 1862 * Whatever flag was set is cleared and the carry sets the 1863 * correct new active state/count. So we don't need to change 1864 * add_arg. 1865 */ 1866 } else { 1867 if ((ngq->queue->el_flags & NGQF_RW) == NGQF_READER) { 1868 /* 1869 * If we had a READ_PENDING and have another one, we 1870 * just want to add READ_PENDING twice (the same as 1871 * adding READER_INCREMENT). If we had WRITE_PENDING, 1872 * we want to add READ_PENDING + WRITE_PENDING to 1873 * clear the old WRITE_PENDING, set ACTIVE_WRITER, 1874 * and set READ_PENDING. Either way we just add 1875 * READ_PENDING to whatever we already had. 1876 */ 1877 add_arg += READ_PENDING; 1878 } else { 1879 /* 1880 * If we had a WRITE_PENDING and have another one, we 1881 * just want to add WRITE_PENDING twice (the same as 1882 * adding ACTIVE_WRITER). If we had READ_PENDING, we 1883 * want to add READ_PENDING + WRITE_PENDING to clear 1884 * the old READ_PENDING, increment the readers, and 1885 * set WRITE_PENDING. Either way we just add 1886 * WRITE_PENDING to whatever we already had. 1887 */ 1888 add_arg += WRITE_PENDING; 1889 } 1890 } 1891 atomic_add_long(&ngq->q_flags, add_arg); 1892 /* 1893 * We have successfully cleared the old pending flag, set the new one 1894 * if it is needed, and incremented the appropriate active field. 1895 * (all in one atomic addition.. wow) 1896 */ 1897 return (item); 1898 } 1899 1900 /* 1901 * Queue a packet to be picked up by someone else. 1902 * We really don't care who, but we can't or don't want to hang around 1903 * to process it ourselves. We are probably an interrupt routine.. 1904 * 1 = writer, 0 = reader 1905 * We should set something to indicate NETISR requested 1906 * If it's the first item queued. 1907 */ 1908 #define NGQRW_R 0 1909 #define NGQRW_W 1 1910 static __inline void 1911 ng_queue_rw(struct ng_queue * ngq, item_p item, int rw) 1912 { 1913 item->el_next = NULL; /* maybe not needed */ 1914 *ngq->last = item; 1915 /* 1916 * If it was the first item in the queue then we need to 1917 * set the last pointer and the type flags. 1918 */ 1919 if (ngq->last == &(ngq->queue)) { 1920 /* 1921 * When called with constants for rw, the optimiser will 1922 * remove the unneeded branch below. 1923 */ 1924 if (rw == NGQRW_W) { 1925 atomic_add_long(&ngq->q_flags, WRITE_PENDING); 1926 } else { 1927 atomic_add_long(&ngq->q_flags, READ_PENDING); 1928 } 1929 } 1930 ngq->last = &(item->el_next); 1931 } 1932 1933 1934 /* 1935 * This function 'cheats' in that it first tries to 'grab' the use of the 1936 * node, without going through the mutex. We can do this becasue of the 1937 * semantics of the lock. The semantics include a clause that says that the 1938 * value of the readers count is invalid if the WRITER_ACTIVE flag is set. It 1939 * also says that the WRITER_ACTIVE flag cannot be set if the readers count 1940 * is not zero. Note that this talks about what is valid to SET the 1941 * WRITER_ACTIVE flag, because from the moment it is set, the value if the 1942 * reader count is immaterial, and not valid. The two 'pending' flags have a 1943 * similar effect, in that If they are orthogonal to the two active fields in 1944 * how they are set, but if either is set, the attempted 'grab' need to be 1945 * backed out because there is earlier work, and we maintain ordering in the 1946 * queue. The result of this is that the reader request can try obtain use of 1947 * the node with only a single atomic addition, and without any of the mutex 1948 * overhead. If this fails the operation degenerates to the same as for other 1949 * cases. 1950 * 1951 */ 1952 static __inline item_p 1953 ng_acquire_read(struct ng_queue *ngq, item_p item) 1954 { 1955 1956 /* ######### Hack alert ######### */ 1957 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 1958 if ((ngq->q_flags & (~READER_MASK)) == 0) { 1959 /* Successfully grabbed node */ 1960 return (item); 1961 } 1962 /* undo the damage if we didn't succeed */ 1963 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 1964 1965 /* ######### End Hack alert ######### */ 1966 mtx_enter((&ngq->q_mtx), MTX_SPIN); 1967 /* 1968 * Try again. Another processor (or interrupt for that matter) may 1969 * have removed the last queued item that was stopping us from 1970 * running, between the previous test, and the moment that we took 1971 * the mutex. (Or maybe a writer completed.) 1972 */ 1973 if ((ngq->q_flags & (~READER_MASK)) == 0) { 1974 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 1975 mtx_exit((&ngq->q_mtx), MTX_SPIN); 1976 return (item); 1977 } 1978 1979 /* 1980 * Quick check that we are doing things right. 1981 */ 1982 if (ngq->q_flags & SINGLE_THREAD_ONLY) { 1983 panic("Calling single treaded queue incorrectly"); 1984 } 1985 1986 /* 1987 * and queue the request for later. 1988 */ 1989 item->el_flags |= NGQF_READER; 1990 ng_queue_rw(ngq, item, NGQRW_R); 1991 1992 /* 1993 * Ok, so that's the item successfully queued for later. So now we 1994 * see if we can dequeue something to run instead. 1995 */ 1996 item = ng_dequeue(ngq); 1997 mtx_exit(&(ngq->q_mtx), MTX_SPIN); 1998 return (item); 1999 } 2000 2001 static __inline item_p 2002 ng_acquire_write(struct ng_queue *ngq, item_p item) 2003 { 2004 restart: 2005 mtx_enter(&(ngq->q_mtx), MTX_SPIN); 2006 /* 2007 * If there are no readers, no writer, and no pending packets, then 2008 * we can just go ahead. In all other situations we need to queue the 2009 * request 2010 */ 2011 if ((ngq->q_flags & (~SINGLE_THREAD_ONLY)) == 0) { 2012 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE); 2013 mtx_exit((&ngq->q_mtx), MTX_SPIN); 2014 if (ngq->q_flags & READER_MASK) { 2015 /* Collision with fast-track reader */ 2016 atomic_add_long(&ngq->q_flags, -WRITER_ACTIVE); 2017 goto restart; 2018 } 2019 2020 return (item); 2021 } 2022 2023 /* 2024 * and queue the request for later. 2025 */ 2026 item->el_flags &= ~NGQF_RW; 2027 ng_queue_rw(ngq, item, NGQRW_W); 2028 2029 /* 2030 * Ok, so that's the item successfully queued for later. So now we 2031 * see if we can dequeue something to run instead. 2032 */ 2033 item = ng_dequeue(ngq); 2034 mtx_exit(&(ngq->q_mtx), MTX_SPIN); 2035 return (item); 2036 } 2037 2038 static __inline void 2039 ng_leave_read(struct ng_queue *ngq) 2040 { 2041 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 2042 } 2043 2044 static __inline void 2045 ng_leave_write(struct ng_queue *ngq) 2046 { 2047 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2048 } 2049 2050 static void 2051 ng_flush_input_queue(struct ng_queue * ngq) 2052 { 2053 item_p item; 2054 u_int add_arg; 2055 mtx_enter(&ngq->q_mtx, MTX_SPIN); 2056 for (;;) { 2057 /* Now take a look at what's on the queue */ 2058 if (ngq->q_flags & READ_PENDING) { 2059 add_arg = -READ_PENDING; 2060 } else if (ngq->q_flags & WRITE_PENDING) { 2061 add_arg = -WRITE_PENDING; 2062 } else { 2063 break; 2064 } 2065 2066 item = ngq->queue; 2067 ngq->queue = item->el_next; 2068 if (ngq->last == &(item->el_next)) { 2069 ngq->last = &(ngq->queue); 2070 } else { 2071 if ((ngq->queue->el_flags & NGQF_RW) == NGQF_READER) { 2072 add_arg += READ_PENDING; 2073 } else { 2074 add_arg += WRITE_PENDING; 2075 } 2076 } 2077 atomic_add_long(&ngq->q_flags, add_arg); 2078 2079 mtx_exit(&ngq->q_mtx, MTX_SPIN); 2080 NG_FREE_ITEM(item); 2081 mtx_enter(&ngq->q_mtx, MTX_SPIN); 2082 } 2083 mtx_exit(&ngq->q_mtx, MTX_SPIN); 2084 } 2085 2086 /*********************************************************************** 2087 * Externally visible method for sending or queueing messages or data. 2088 ***********************************************************************/ 2089 2090 /* 2091 * MACRO WILL DO THE JOB OF CALLING ng_package_msg IN CALLER 2092 * before we are called. The user code should have filled out the item 2093 * correctly by this stage: 2094 * Common: 2095 * reference to destination node. 2096 * Reference to destination rcv hook if relevant. 2097 * Data: 2098 * pointer to mbuf 2099 * pointer to metadata 2100 * Control_Message: 2101 * pointer to msg. 2102 * ID of original sender node. (return address) 2103 * 2104 * The nodes have several routines and macros to help with this task: 2105 * ng_package_msg() 2106 * ng_package_data() do much of the work. 2107 * ng_retarget_msg 2108 * ng_retarget_data 2109 */ 2110 2111 int 2112 ng_snd_item(item_p item, int queue) 2113 { 2114 hook_p hook = item->el_hook; 2115 node_p dest = item->el_dest; 2116 int rw; 2117 int error = 0, ierror; 2118 item_p oitem; 2119 struct ng_queue * ngq = &dest->nd_input_queue; 2120 2121 #ifdef NETGRAPH_DEBUG 2122 _ngi_check(item, __FILE__, __LINE__); 2123 #endif 2124 2125 if (item == NULL) { 2126 TRAP_ERROR(); 2127 return (EINVAL); /* failed to get queue element */ 2128 } 2129 if (dest == NULL) { 2130 NG_FREE_ITEM(item); 2131 TRAP_ERROR(); 2132 return (EINVAL); /* No address */ 2133 } 2134 switch(item->el_flags & NGQF_TYPE) { 2135 case NGQF_DATA: 2136 /* 2137 * DATA MESSAGE 2138 * Delivered to a node via a non-optional hook. 2139 * Both should be present in the item even though 2140 * the node is derivable from the hook. 2141 * References are held on both by the item. 2142 */ 2143 #ifdef NETGRAPH_DEBUG 2144 _ngi_check(item, __FILE__, __LINE__); 2145 #endif 2146 CHECK_DATA_MBUF(NGI_M(item)); 2147 if (hook == NULL) { 2148 NG_FREE_ITEM(item); 2149 TRAP_ERROR(); 2150 return(EINVAL); 2151 } 2152 if ((NG_HOOK_NOT_VALID(hook)) 2153 || (NG_NODE_NOT_VALID(NG_HOOK_NODE(hook)))) { 2154 NG_FREE_ITEM(item); 2155 return (ENOTCONN); 2156 } 2157 if ((hook->hk_flags & HK_QUEUE)) { 2158 queue = 1; 2159 } 2160 /* By default data is a reader in the locking scheme */ 2161 item->el_flags |= NGQF_READER; 2162 rw = NGQRW_R; 2163 break; 2164 case NGQF_MESG: 2165 /* 2166 * CONTROL MESSAGE 2167 * Delivered to a node. 2168 * Hook is optional. 2169 * References are held by the item on the node and 2170 * the hook if it is present. 2171 */ 2172 if (hook && (hook->hk_flags & HK_QUEUE)) { 2173 queue = 1; 2174 } 2175 /* Data messages count as writers unles explicitly exempted */ 2176 if (NGI_MSG(item)->header.cmd & NGM_READONLY) { 2177 item->el_flags |= NGQF_READER; 2178 rw = NGQRW_R; 2179 } else { 2180 item->el_flags &= ~NGQF_RW; 2181 rw = NGQRW_W; 2182 } 2183 break; 2184 case NGQF_FN: 2185 item->el_flags &= ~NGQF_RW; 2186 rw = NGQRW_W; 2187 break; 2188 default: 2189 NG_FREE_ITEM(item); 2190 TRAP_ERROR(); 2191 return (EINVAL); 2192 } 2193 /* 2194 * If the node specifies single threading, force writer semantics 2195 * Similarly the node may say one hook always produces writers. 2196 * These are over-rides. 2197 */ 2198 if ((ngq->q_flags & SINGLE_THREAD_ONLY) 2199 || (dest->nd_flags & NG_FORCE_WRITER) 2200 || (hook && (hook->hk_flags & HK_FORCE_WRITER))) { 2201 rw = NGQRW_W; 2202 item->el_flags &= ~NGQF_READER; 2203 } 2204 if (queue) { 2205 /* Put it on the queue for that node*/ 2206 #ifdef NETGRAPH_DEBUG 2207 _ngi_check(item, __FILE__, __LINE__); 2208 #endif 2209 mtx_enter(&(ngq->q_mtx), MTX_SPIN); 2210 ng_queue_rw(ngq, item, rw); 2211 mtx_exit(&(ngq->q_mtx), MTX_SPIN); 2212 /* 2213 * If there are active elements then we can rely on 2214 * them. if not we should not rely on another packet 2215 * coming here by another path, 2216 * so it is best to put us in the netisr list. 2217 */ 2218 if ((ngq->q_flags & (READER_MASK|WRITER_ACTIVE)) == 0) { 2219 ng_setisr(ngq->q_node); 2220 } 2221 return (0); 2222 } 2223 /* 2224 * Take a queue item and a node and see if we can apply the item to 2225 * the node. We may end up getting a different item to apply instead. 2226 * Will allow for a piggyback reply only in the case where 2227 * there is no queueing. 2228 */ 2229 2230 oitem = item; 2231 /* 2232 * We already decided how we will be queueud or treated. 2233 * Try get the appropriate operating permission. 2234 */ 2235 if (rw == NGQRW_R) { 2236 item = ng_acquire_read(ngq, item); 2237 } else { 2238 item = ng_acquire_write(ngq, item); 2239 } 2240 2241 /* 2242 * May have come back with a different item. 2243 * or maybe none at all. The one we started with will 2244 * have been queued in thises cases. 2245 */ 2246 if (item == NULL) { 2247 return (0); 2248 } 2249 2250 #ifdef NETGRAPH_DEBUG 2251 _ngi_check(item, __FILE__, __LINE__); 2252 #endif 2253 ierror = ng_apply_item(dest, item); /* drops r/w lock when done */ 2254 2255 /* only return an error if it was our initial item.. (compat hack) */ 2256 if (oitem == item) { 2257 error = ierror; 2258 } 2259 2260 /* 2261 * Now we've handled the packet we brought, (or a friend of it) let's 2262 * look for any other packets that may have been queued up. We hold 2263 * no locks, so if someone puts something in the queue after 2264 * we check that it is empty, it is their problem 2265 * to ensure it is processed. If we have the netisr thread cme in here 2266 * while we still say we have stuff to do, we may get a boost 2267 * in SMP systems. :-) 2268 */ 2269 for (;;) { 2270 /* quick hack to save all that mutex stuff */ 2271 if ((ngq->q_flags & (WRITE_PENDING | READ_PENDING)) == 0) { 2272 if (dest->nd_flags & NG_WORKQ) 2273 ng_worklist_remove(dest); 2274 return (0); 2275 } 2276 /* 2277 * dequeue acquires and adjusts the input_queue as it dequeues 2278 * packets. It acquires the rw lock as needed. 2279 */ 2280 mtx_enter(&ngq->q_mtx, MTX_SPIN); 2281 item = ng_dequeue(ngq); 2282 mtx_exit(&ngq->q_mtx, MTX_SPIN); 2283 if (!item) { 2284 /* 2285 * If we have no work to do 2286 * then we certainly don't need to be 2287 * on the worklist. 2288 */ 2289 if (dest->nd_flags & NG_WORKQ) 2290 ng_worklist_remove(dest); 2291 return (0); 2292 } 2293 #ifdef NETGRAPH_DEBUG 2294 _ngi_check(item, __FILE__, __LINE__); 2295 #endif 2296 2297 /* 2298 * We have the appropriate lock, so run the item. 2299 * When finished it will drop the lock accordingly 2300 */ 2301 2302 ierror = ng_apply_item(dest, item); 2303 /* 2304 * only return an error if it was our initial 2305 * item.. (compat hack) 2306 */ 2307 if (oitem == item) { 2308 error = ierror; 2309 } 2310 } 2311 return (0); 2312 } 2313 2314 /* 2315 * We have an item that was possibly queued somewhere. 2316 * It should contain all the information needed 2317 * to run it on the appropriate node/hook. 2318 */ 2319 static int 2320 ng_apply_item(node_p node, item_p item) 2321 { 2322 hook_p hook; 2323 int was_reader = ((item->el_flags & NGQF_RW)); 2324 int error = 0; 2325 ng_rcvdata_t *rcvdata; 2326 2327 hook = item->el_hook; 2328 item->el_hook = NULL; /* so NG_FREE_ITEM doesn't NG_HOOK_UNREF() */ 2329 /* We already have the node.. assume responsibility */ 2330 /* And the reference */ 2331 /* node = item->el_dest; */ 2332 item->el_dest = NULL; /* same as for the hook above */ 2333 #ifdef NETGRAPH_DEBUG 2334 _ngi_check(item, __FILE__, __LINE__); 2335 #endif 2336 switch (item->el_flags & NGQF_TYPE) { 2337 case NGQF_DATA: 2338 /* 2339 * Check things are still ok as when we were queued. 2340 */ 2341 2342 if ((hook == NULL) 2343 || NG_HOOK_NOT_VALID(hook) 2344 || NG_NODE_NOT_VALID(node) 2345 || ((rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata) == NULL)) { 2346 error = EIO; 2347 NG_FREE_ITEM(item); 2348 } else { 2349 error = (*rcvdata)(hook, item); 2350 } 2351 break; 2352 case NGQF_MESG: 2353 if (hook) { 2354 item->el_hook = NULL; 2355 if (NG_HOOK_NOT_VALID(hook)) { 2356 /* 2357 * If the hook has been zapped then we can't use it. 2358 * Immediatly drop its reference. 2359 * The message may not need it. 2360 */ 2361 NG_HOOK_UNREF(hook); 2362 hook = NULL; 2363 } 2364 } 2365 /* 2366 * Similarly, if the node is a zombie there is 2367 * nothing we can do with it, drop everything. 2368 */ 2369 if (NG_NODE_NOT_VALID(node)) { 2370 TRAP_ERROR(); 2371 error = EINVAL; 2372 NG_FREE_ITEM(item); 2373 } else { 2374 /* 2375 * Call the appropriate message handler for the object. 2376 * It is up to the message handler to free the message. 2377 * If it's a generic message, handle it generically, 2378 * otherwise call the type's message handler 2379 * (if it exists) 2380 * XXX (race). Remember that a queued message may 2381 * reference a node or hook that has just been 2382 * invalidated. It will exist as the queue code 2383 * is holding a reference, but.. 2384 */ 2385 2386 struct ng_mesg *msg = NGI_MSG(item); 2387 2388 if ((msg->header.typecookie == NGM_GENERIC_COOKIE) 2389 && ((msg->header.flags & NGF_RESP) == 0)) { 2390 error = ng_generic_msg(node, item, hook); 2391 } else { 2392 if ((node)->nd_type->rcvmsg != NULL) { 2393 error = (*(node)->nd_type->rcvmsg)((node), 2394 (item), (hook)); 2395 } else { 2396 TRAP_ERROR(); 2397 error = EINVAL; /* XXX */ 2398 NG_FREE_ITEM(item); 2399 } 2400 } 2401 /* item is now invalid */ 2402 } 2403 break; 2404 case NGQF_FN: 2405 /* 2406 * We have to implicitly trust the hook, 2407 * as some of these are used for system purposes 2408 * where the hook is invalid. 2409 */ 2410 if (NG_NODE_NOT_VALID(node)) { 2411 TRAP_ERROR(); 2412 error = EINVAL; 2413 break; 2414 } 2415 error = 2416 (*NGI_FN(item))(node, hook, NGI_ARG1(item), NGI_ARG2(item)); 2417 2418 NG_FREE_ITEM(item); 2419 break; 2420 2421 } 2422 /* 2423 * We held references on some of the resources 2424 * that we took from the item. Now that we have 2425 * finished doing everything, drop those references. 2426 */ 2427 if (hook) { 2428 NG_HOOK_UNREF(hook); 2429 } 2430 2431 if (was_reader) { 2432 ng_leave_read(&node->nd_input_queue); 2433 } else { 2434 ng_leave_write(&node->nd_input_queue); 2435 } 2436 NG_NODE_UNREF(node); 2437 return (error); 2438 } 2439 2440 /*********************************************************************** 2441 * Implement the 'generic' control messages 2442 ***********************************************************************/ 2443 static int 2444 ng_generic_msg(node_p here, item_p item, hook_p lasthook) 2445 { 2446 int error = 0; 2447 struct ng_mesg *msg; 2448 struct ng_mesg *resp = NULL; 2449 2450 NGI_GET_MSG(item, msg); 2451 if (msg->header.typecookie != NGM_GENERIC_COOKIE) { 2452 TRAP_ERROR(); 2453 error = EINVAL; 2454 goto out; 2455 } 2456 switch (msg->header.cmd) { 2457 case NGM_SHUTDOWN: 2458 ng_rmnode(here); 2459 break; 2460 case NGM_MKPEER: 2461 { 2462 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data; 2463 2464 if (msg->header.arglen != sizeof(*mkp)) { 2465 TRAP_ERROR(); 2466 error = EINVAL; 2467 break; 2468 } 2469 mkp->type[sizeof(mkp->type) - 1] = '\0'; 2470 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0'; 2471 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0'; 2472 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type); 2473 break; 2474 } 2475 case NGM_CONNECT: 2476 { 2477 struct ngm_connect *const con = 2478 (struct ngm_connect *) msg->data; 2479 node_p node2; 2480 2481 if (msg->header.arglen != sizeof(*con)) { 2482 TRAP_ERROR(); 2483 error = EINVAL; 2484 break; 2485 } 2486 con->path[sizeof(con->path) - 1] = '\0'; 2487 con->ourhook[sizeof(con->ourhook) - 1] = '\0'; 2488 con->peerhook[sizeof(con->peerhook) - 1] = '\0'; 2489 /* Don't forget we get a reference.. */ 2490 error = ng_path2noderef(here, con->path, &node2, NULL); 2491 if (error) 2492 break; 2493 error = ng_con_nodes(here, con->ourhook, node2, con->peerhook); 2494 NG_NODE_UNREF(node2); 2495 break; 2496 } 2497 case NGM_NAME: 2498 { 2499 struct ngm_name *const nam = (struct ngm_name *) msg->data; 2500 2501 if (msg->header.arglen != sizeof(*nam)) { 2502 TRAP_ERROR(); 2503 error = EINVAL; 2504 break; 2505 } 2506 nam->name[sizeof(nam->name) - 1] = '\0'; 2507 error = ng_name_node(here, nam->name); 2508 break; 2509 } 2510 case NGM_RMHOOK: 2511 { 2512 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data; 2513 hook_p hook; 2514 2515 if (msg->header.arglen != sizeof(*rmh)) { 2516 TRAP_ERROR(); 2517 error = EINVAL; 2518 break; 2519 } 2520 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0'; 2521 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL) 2522 ng_destroy_hook(hook); 2523 break; 2524 } 2525 case NGM_NODEINFO: 2526 { 2527 struct nodeinfo *ni; 2528 2529 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT); 2530 if (resp == NULL) { 2531 error = ENOMEM; 2532 break; 2533 } 2534 2535 /* Fill in node info */ 2536 ni = (struct nodeinfo *) resp->data; 2537 if (NG_NODE_HAS_NAME(here)) 2538 strncpy(ni->name, NG_NODE_NAME(here), NG_NODELEN); 2539 strncpy(ni->type, here->nd_type->name, NG_TYPELEN); 2540 ni->id = ng_node2ID(here); 2541 ni->hooks = here->nd_numhooks; 2542 break; 2543 } 2544 case NGM_LISTHOOKS: 2545 { 2546 const int nhooks = here->nd_numhooks; 2547 struct hooklist *hl; 2548 struct nodeinfo *ni; 2549 hook_p hook; 2550 2551 /* Get response struct */ 2552 NG_MKRESPONSE(resp, msg, sizeof(*hl) 2553 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT); 2554 if (resp == NULL) { 2555 error = ENOMEM; 2556 break; 2557 } 2558 hl = (struct hooklist *) resp->data; 2559 ni = &hl->nodeinfo; 2560 2561 /* Fill in node info */ 2562 if (NG_NODE_HAS_NAME(here)) 2563 strncpy(ni->name, NG_NODE_NAME(here), NG_NODELEN); 2564 strncpy(ni->type, here->nd_type->name, NG_TYPELEN); 2565 ni->id = ng_node2ID(here); 2566 2567 /* Cycle through the linked list of hooks */ 2568 ni->hooks = 0; 2569 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) { 2570 struct linkinfo *const link = &hl->link[ni->hooks]; 2571 2572 if (ni->hooks >= nhooks) { 2573 log(LOG_ERR, "%s: number of %s changed\n", 2574 __FUNCTION__, "hooks"); 2575 break; 2576 } 2577 if (NG_HOOK_NOT_VALID(hook)) 2578 continue; 2579 strncpy(link->ourhook, NG_HOOK_NAME(hook), NG_HOOKLEN); 2580 strncpy(link->peerhook, 2581 NG_PEER_HOOK_NAME(hook), NG_HOOKLEN); 2582 if (NG_PEER_NODE_NAME(hook)[0] != '\0') 2583 strncpy(link->nodeinfo.name, 2584 NG_PEER_NODE_NAME(hook), NG_NODELEN); 2585 strncpy(link->nodeinfo.type, 2586 NG_PEER_NODE(hook)->nd_type->name, NG_TYPELEN); 2587 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook)); 2588 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks; 2589 ni->hooks++; 2590 } 2591 break; 2592 } 2593 2594 case NGM_LISTNAMES: 2595 case NGM_LISTNODES: 2596 { 2597 const int unnamed = (msg->header.cmd == NGM_LISTNODES); 2598 struct namelist *nl; 2599 node_p node; 2600 int num = 0; 2601 2602 mtx_enter(&ng_nodelist_mtx, MTX_DEF); 2603 /* Count number of nodes */ 2604 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2605 if (NG_NODE_IS_VALID(node) 2606 && (unnamed || NG_NODE_HAS_NAME(node))) { 2607 num++; 2608 } 2609 } 2610 mtx_exit(&ng_nodelist_mtx, MTX_DEF); 2611 2612 /* Get response struct */ 2613 NG_MKRESPONSE(resp, msg, sizeof(*nl) 2614 + (num * sizeof(struct nodeinfo)), M_NOWAIT); 2615 if (resp == NULL) { 2616 error = ENOMEM; 2617 break; 2618 } 2619 nl = (struct namelist *) resp->data; 2620 2621 /* Cycle through the linked list of nodes */ 2622 nl->numnames = 0; 2623 mtx_enter(&ng_nodelist_mtx, MTX_DEF); 2624 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2625 struct nodeinfo *const np = &nl->nodeinfo[nl->numnames]; 2626 2627 if (nl->numnames >= num) { 2628 log(LOG_ERR, "%s: number of %s changed\n", 2629 __FUNCTION__, "nodes"); 2630 break; 2631 } 2632 if (NG_NODE_NOT_VALID(node)) 2633 continue; 2634 if (!unnamed && (! NG_NODE_HAS_NAME(node))) 2635 continue; 2636 if (NG_NODE_HAS_NAME(node)) 2637 strncpy(np->name, NG_NODE_NAME(node), NG_NODELEN); 2638 strncpy(np->type, node->nd_type->name, NG_TYPELEN); 2639 np->id = ng_node2ID(node); 2640 np->hooks = node->nd_numhooks; 2641 nl->numnames++; 2642 } 2643 mtx_exit(&ng_nodelist_mtx, MTX_DEF); 2644 break; 2645 } 2646 2647 case NGM_LISTTYPES: 2648 { 2649 struct typelist *tl; 2650 struct ng_type *type; 2651 int num = 0; 2652 2653 mtx_enter(&ng_typelist_mtx, MTX_DEF); 2654 /* Count number of types */ 2655 LIST_FOREACH(type, &ng_typelist, types) { 2656 num++; 2657 } 2658 mtx_exit(&ng_typelist_mtx, MTX_DEF); 2659 2660 /* Get response struct */ 2661 NG_MKRESPONSE(resp, msg, sizeof(*tl) 2662 + (num * sizeof(struct typeinfo)), M_NOWAIT); 2663 if (resp == NULL) { 2664 error = ENOMEM; 2665 break; 2666 } 2667 tl = (struct typelist *) resp->data; 2668 2669 /* Cycle through the linked list of types */ 2670 tl->numtypes = 0; 2671 mtx_enter(&ng_typelist_mtx, MTX_DEF); 2672 LIST_FOREACH(type, &ng_typelist, types) { 2673 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes]; 2674 2675 if (tl->numtypes >= num) { 2676 log(LOG_ERR, "%s: number of %s changed\n", 2677 __FUNCTION__, "types"); 2678 break; 2679 } 2680 strncpy(tp->type_name, type->name, NG_TYPELEN); 2681 tp->numnodes = type->refs; 2682 tl->numtypes++; 2683 } 2684 mtx_exit(&ng_typelist_mtx, MTX_DEF); 2685 break; 2686 } 2687 2688 case NGM_BINARY2ASCII: 2689 { 2690 int bufSize = 20 * 1024; /* XXX hard coded constant */ 2691 const struct ng_parse_type *argstype; 2692 const struct ng_cmdlist *c; 2693 struct ng_mesg *binary, *ascii; 2694 2695 /* Data area must contain a valid netgraph message */ 2696 binary = (struct ng_mesg *)msg->data; 2697 if (msg->header.arglen < sizeof(struct ng_mesg) 2698 || (msg->header.arglen - sizeof(struct ng_mesg) 2699 < binary->header.arglen)) { 2700 TRAP_ERROR(); 2701 error = EINVAL; 2702 break; 2703 } 2704 2705 /* Get a response message with lots of room */ 2706 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT); 2707 if (resp == NULL) { 2708 error = ENOMEM; 2709 break; 2710 } 2711 ascii = (struct ng_mesg *)resp->data; 2712 2713 /* Copy binary message header to response message payload */ 2714 bcopy(binary, ascii, sizeof(*binary)); 2715 2716 /* Find command by matching typecookie and command number */ 2717 for (c = here->nd_type->cmdlist; 2718 c != NULL && c->name != NULL; c++) { 2719 if (binary->header.typecookie == c->cookie 2720 && binary->header.cmd == c->cmd) 2721 break; 2722 } 2723 if (c == NULL || c->name == NULL) { 2724 for (c = ng_generic_cmds; c->name != NULL; c++) { 2725 if (binary->header.typecookie == c->cookie 2726 && binary->header.cmd == c->cmd) 2727 break; 2728 } 2729 if (c->name == NULL) { 2730 NG_FREE_MSG(resp); 2731 error = ENOSYS; 2732 break; 2733 } 2734 } 2735 2736 /* Convert command name to ASCII */ 2737 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr), 2738 "%s", c->name); 2739 2740 /* Convert command arguments to ASCII */ 2741 argstype = (binary->header.flags & NGF_RESP) ? 2742 c->respType : c->mesgType; 2743 if (argstype == NULL) { 2744 *ascii->data = '\0'; 2745 } else { 2746 if ((error = ng_unparse(argstype, 2747 (u_char *)binary->data, 2748 ascii->data, bufSize)) != 0) { 2749 NG_FREE_MSG(resp); 2750 break; 2751 } 2752 } 2753 2754 /* Return the result as struct ng_mesg plus ASCII string */ 2755 bufSize = strlen(ascii->data) + 1; 2756 ascii->header.arglen = bufSize; 2757 resp->header.arglen = sizeof(*ascii) + bufSize; 2758 break; 2759 } 2760 2761 case NGM_ASCII2BINARY: 2762 { 2763 int bufSize = 2000; /* XXX hard coded constant */ 2764 const struct ng_cmdlist *c; 2765 const struct ng_parse_type *argstype; 2766 struct ng_mesg *ascii, *binary; 2767 int off = 0; 2768 2769 /* Data area must contain at least a struct ng_mesg + '\0' */ 2770 ascii = (struct ng_mesg *)msg->data; 2771 if ((msg->header.arglen < sizeof(*ascii) + 1) 2772 || (ascii->header.arglen < 1) 2773 || (msg->header.arglen 2774 < sizeof(*ascii) + ascii->header.arglen)) { 2775 TRAP_ERROR(); 2776 error = EINVAL; 2777 break; 2778 } 2779 ascii->data[ascii->header.arglen - 1] = '\0'; 2780 2781 /* Get a response message with lots of room */ 2782 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT); 2783 if (resp == NULL) { 2784 error = ENOMEM; 2785 break; 2786 } 2787 binary = (struct ng_mesg *)resp->data; 2788 2789 /* Copy ASCII message header to response message payload */ 2790 bcopy(ascii, binary, sizeof(*ascii)); 2791 2792 /* Find command by matching ASCII command string */ 2793 for (c = here->nd_type->cmdlist; 2794 c != NULL && c->name != NULL; c++) { 2795 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2796 break; 2797 } 2798 if (c == NULL || c->name == NULL) { 2799 for (c = ng_generic_cmds; c->name != NULL; c++) { 2800 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2801 break; 2802 } 2803 if (c->name == NULL) { 2804 NG_FREE_MSG(resp); 2805 error = ENOSYS; 2806 break; 2807 } 2808 } 2809 2810 /* Convert command name to binary */ 2811 binary->header.cmd = c->cmd; 2812 binary->header.typecookie = c->cookie; 2813 2814 /* Convert command arguments to binary */ 2815 argstype = (binary->header.flags & NGF_RESP) ? 2816 c->respType : c->mesgType; 2817 if (argstype == NULL) { 2818 bufSize = 0; 2819 } else { 2820 if ((error = ng_parse(argstype, ascii->data, 2821 &off, (u_char *)binary->data, &bufSize)) != 0) { 2822 NG_FREE_MSG(resp); 2823 break; 2824 } 2825 } 2826 2827 /* Return the result */ 2828 binary->header.arglen = bufSize; 2829 resp->header.arglen = sizeof(*binary) + bufSize; 2830 break; 2831 } 2832 2833 case NGM_TEXT_CONFIG: 2834 case NGM_TEXT_STATUS: 2835 /* 2836 * This one is tricky as it passes the command down to the 2837 * actual node, even though it is a generic type command. 2838 * This means we must assume that the item/msg is already freed 2839 * when control passes back to us. 2840 */ 2841 if (here->nd_type->rcvmsg != NULL) { 2842 NGI_MSG(item) = msg; /* put it back as we found it */ 2843 return((*here->nd_type->rcvmsg)(here, item, lasthook)); 2844 } 2845 /* Fall through if rcvmsg not supported */ 2846 default: 2847 TRAP_ERROR(); 2848 error = EINVAL; 2849 } 2850 /* 2851 * Sometimes a generic message may be statically allocated 2852 * to avoid problems with allocating when in tight memeory situations. 2853 * Don't free it if it is so. 2854 * I break them appart here, because erros may cause a free if the item 2855 * in which case we'd be doing it twice. 2856 * they are kept together above, to simplify freeing. 2857 */ 2858 out: 2859 NG_RESPOND_MSG(error, here, item, resp); 2860 if ( msg && ((msg->header.flags & NGF_STATIC) == 0)) 2861 NG_FREE_MSG(msg); 2862 return (error); 2863 } 2864 2865 /* 2866 * Copy a 'meta'. 2867 * 2868 * Returns new meta, or NULL if original meta is NULL or ENOMEM. 2869 */ 2870 meta_p 2871 ng_copy_meta(meta_p meta) 2872 { 2873 meta_p meta2; 2874 2875 if (meta == NULL) 2876 return (NULL); 2877 MALLOC(meta2, meta_p, meta->used_len, M_NETGRAPH_META, M_NOWAIT); 2878 if (meta2 == NULL) 2879 return (NULL); 2880 meta2->allocated_len = meta->used_len; 2881 bcopy(meta, meta2, meta->used_len); 2882 return (meta2); 2883 } 2884 2885 /************************************************************************ 2886 Module routines 2887 ************************************************************************/ 2888 2889 /* 2890 * Handle the loading/unloading of a netgraph node type module 2891 */ 2892 int 2893 ng_mod_event(module_t mod, int event, void *data) 2894 { 2895 struct ng_type *const type = data; 2896 int s, error = 0; 2897 2898 switch (event) { 2899 case MOD_LOAD: 2900 2901 /* Register new netgraph node type */ 2902 s = splnet(); 2903 if ((error = ng_newtype(type)) != 0) { 2904 splx(s); 2905 break; 2906 } 2907 2908 /* Call type specific code */ 2909 if (type->mod_event != NULL) 2910 if ((error = (*type->mod_event)(mod, event, data))) { 2911 mtx_enter(&ng_typelist_mtx, MTX_DEF); 2912 LIST_REMOVE(type, types); 2913 mtx_exit(&ng_typelist_mtx, MTX_DEF); 2914 } 2915 splx(s); 2916 break; 2917 2918 case MOD_UNLOAD: 2919 s = splnet(); 2920 if (type->refs != 0) /* make sure no nodes exist! */ 2921 error = EBUSY; 2922 else { 2923 if (type->mod_event != NULL) { /* check with type */ 2924 error = (*type->mod_event)(mod, event, data); 2925 if (error != 0) { /* type refuses.. */ 2926 splx(s); 2927 break; 2928 } 2929 } 2930 mtx_enter(&ng_typelist_mtx, MTX_DEF); 2931 LIST_REMOVE(type, types); 2932 mtx_exit(&ng_typelist_mtx, MTX_DEF); 2933 } 2934 splx(s); 2935 break; 2936 2937 default: 2938 if (type->mod_event != NULL) 2939 error = (*type->mod_event)(mod, event, data); 2940 else 2941 error = 0; /* XXX ? */ 2942 break; 2943 } 2944 return (error); 2945 } 2946 2947 /* 2948 * Handle loading and unloading for this code. 2949 * The only thing we need to link into is the NETISR strucure. 2950 */ 2951 static int 2952 ngb_mod_event(module_t mod, int event, void *data) 2953 { 2954 int s, error = 0; 2955 2956 switch (event) { 2957 case MOD_LOAD: 2958 /* Register line discipline */ 2959 mtx_init(&ng_worklist_mtx, "netgraph worklist mutex", 0); 2960 mtx_init(&ng_typelist_mtx, "netgraph types mutex", 0); 2961 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", 0); 2962 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", 0); 2963 mtx_init(&ngq_mtx, "netgraph netisr mutex", 0); 2964 s = splimp(); 2965 error = register_netisr(NETISR_NETGRAPH, ngintr); 2966 splx(s); 2967 break; 2968 case MOD_UNLOAD: 2969 /* You cant unload it because an interface may be using it. */ 2970 error = EBUSY; 2971 break; 2972 default: 2973 error = EOPNOTSUPP; 2974 break; 2975 } 2976 return (error); 2977 } 2978 2979 static moduledata_t netgraph_mod = { 2980 "netgraph", 2981 ngb_mod_event, 2982 (NULL) 2983 }; 2984 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE); 2985 2986 /************************************************************************ 2987 Queue element get/free routines 2988 ************************************************************************/ 2989 2990 2991 static int allocated; /* number of items malloc'd */ 2992 static int maxalloc = 128; /* limit the damage of a leak */ 2993 static const int ngqfreemax = 64;/* cache at most this many */ 2994 static const int ngqfreelow = 4; /* try malloc if free < this */ 2995 static volatile int ngqfreesize; /* number of cached entries */ 2996 #ifdef NETGRAPH_DEBUG 2997 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist); 2998 #endif 2999 /* 3000 * Get a queue entry 3001 * This is usually called when a packet first enters netgraph. 3002 * By definition, this is usually from an interrupt, or from a user. 3003 * Users are not so important, but try be quick for the times that it's 3004 * an interrupt. Use atomic operations to cope with collisions 3005 * with interrupts and other processors. Assumes MALLOC is SMP safe. 3006 * XXX If reserve is low, we should try to get 2 from malloc as this 3007 * would indicate it often fails. 3008 */ 3009 static item_p 3010 ng_getqblk(void) 3011 { 3012 item_p item = NULL; 3013 3014 /* 3015 * Try get a cached queue block, or else allocate a new one 3016 * If we are less than our reserve, try malloc. If malloc 3017 * fails, then that's what the reserve is for... 3018 * Don't completely trust ngqfreesize, as it is subject 3019 * to races.. (it'll eventually catch up but may be out by one or two 3020 * for brief moments(under SMP or interrupts). 3021 * ngqfree is the final arbiter. We have our little reserve 3022 * because we use M_NOWAIT for malloc. This just helps us 3023 * avoid dropping packets while not increasing the time 3024 * we take to service the interrupt (on average) (we hope). 3025 */ 3026 for (;;) { 3027 if ((ngqfreesize < ngqfreelow) || (ngqfree == NULL)) { 3028 if (allocated < maxalloc) { /* don't leak forever */ 3029 MALLOC(item, item_p , 3030 sizeof(*item), M_NETGRAPH_ITEM, 3031 (M_NOWAIT | M_ZERO)); 3032 if (item) { 3033 #ifdef NETGRAPH_DEBUG 3034 TAILQ_INSERT_TAIL(&ng_itemlist, 3035 item, all); 3036 #endif /* NETGRAPH_DEBUG */ 3037 atomic_add_int(&allocated, 1); 3038 break; 3039 } 3040 } 3041 } 3042 3043 /* 3044 * We didn't or couldn't malloc. 3045 * try get one from our cache. 3046 * item must be NULL to get here. 3047 */ 3048 if ((item = ngqfree) != NULL) { 3049 /* 3050 * Atomically try grab the first item 3051 * and put it's successor in its place. 3052 * If we fail, just try again.. someone else 3053 * beat us to this one or freed one. 3054 * Don't worry about races with ngqfreesize. 3055 * Close enough is good enough.. 3056 */ 3057 if (atomic_cmpset_ptr(&ngqfree, item, item->el_next)) { 3058 atomic_subtract_int(&ngqfreesize, 1); 3059 break; 3060 } 3061 item = NULL; 3062 } else { 3063 /* We really ran out */ 3064 break; 3065 } 3066 } 3067 item->el_flags &= ~NGQF_FREE; 3068 return (item); 3069 } 3070 3071 /* 3072 * Release a queue entry 3073 */ 3074 void 3075 ng_free_item(item_p item) 3076 { 3077 3078 /* 3079 * The item may hold resources on it's own. We need to free 3080 * these before we can free the item. What they are depends upon 3081 * what kind of item it is. it is important that nodes zero 3082 * out pointers to resources that they remove from the item 3083 * or we release them again here. 3084 */ 3085 if (item->el_flags & NGQF_FREE) { 3086 panic(" Freeing free queue item"); 3087 } 3088 switch (item->el_flags & NGQF_TYPE) { 3089 case NGQF_DATA: 3090 /* If we have an mbuf and metadata still attached.. */ 3091 NG_FREE_M(_NGI_M(item)); 3092 NG_FREE_META(_NGI_META(item)); 3093 break; 3094 case NGQF_MESG: 3095 _NGI_RETADDR(item) = NULL; 3096 NG_FREE_MSG(_NGI_MSG(item)); 3097 break; 3098 case NGQF_FN: 3099 /* nothing to free really, */ 3100 _NGI_FN(item) = NULL; 3101 _NGI_ARG1(item) = NULL; 3102 _NGI_ARG2(item) = 0; 3103 case NGQF_UNDEF: 3104 } 3105 /* If we still have a node or hook referenced... */ 3106 if (item->el_dest) { 3107 NG_NODE_UNREF(item->el_dest); 3108 item->el_dest = NULL; 3109 } 3110 if (item->el_hook) { 3111 NG_HOOK_UNREF(item->el_hook); 3112 item->el_hook = NULL; 3113 } 3114 item->el_flags |= NGQF_FREE; 3115 3116 /* 3117 * We have freed any resources held by the item. 3118 * now we can free the item itself. 3119 */ 3120 if (ngqfreesize < ngqfreemax) { /* don't worry about races */ 3121 for (;;) { 3122 item->el_next = ngqfree; 3123 if (atomic_cmpset_ptr(&ngqfree, item->el_next, item)) { 3124 break; 3125 } 3126 } 3127 atomic_add_int(&ngqfreesize, 1); 3128 } else { 3129 /* This is the only place that should use this Macro */ 3130 #ifdef NETGRAPH_DEBUG 3131 TAILQ_REMOVE(&ng_itemlist, item, all); 3132 #endif /* NETGRAPH_DEBUG */ 3133 NG_FREE_ITEM_REAL(item); 3134 atomic_subtract_int(&allocated, 1); 3135 } 3136 } 3137 3138 #ifdef NETGRAPH_DEBUG 3139 void 3140 dumphook (hook_p hook, char *file, int line) 3141 { 3142 printf("hook: name %s, %d refs, Last touched:\n", 3143 _NG_HOOK_NAME(hook), hook->hk_refs); 3144 printf(" Last active @ %s, line %d\n", 3145 hook->lastfile, hook->lastline); 3146 if (line) { 3147 printf(" problem discovered at file %s, line %d\n", file, line); 3148 } 3149 } 3150 3151 void 3152 dumpnode(node_p node, char *file, int line) 3153 { 3154 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n", 3155 _NG_NODE_ID(node), node->nd_type->name, 3156 node->nd_numhooks, node->nd_flags, 3157 node->nd_refs, node->nd_name); 3158 printf(" Last active @ %s, line %d\n", 3159 node->lastfile, node->lastline); 3160 if (line) { 3161 printf(" problem discovered at file %s, line %d\n", file, line); 3162 } 3163 } 3164 3165 void 3166 dumpitem(item_p item, char *file, int line) 3167 { 3168 if (item->el_flags & NGQF_FREE) { 3169 printf(" Free item, freed at %s, line %d\n", 3170 item->lastfile, item->lastline); 3171 } else { 3172 printf(" ACTIVE item, last used at %s, line %d", 3173 item->lastfile, item->lastline); 3174 switch(item->el_flags & NGQF_TYPE) { 3175 case NGQF_DATA: 3176 printf(" - [data]\n"); 3177 break; 3178 case NGQF_MESG: 3179 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item)); 3180 break; 3181 case NGQF_FN: 3182 printf(" - fn@%p (%p, %p, %p, %d (%x))\n", 3183 item->body.fn.fn_fn, 3184 item->el_dest, 3185 item->el_hook, 3186 item->body.fn.fn_arg1, 3187 item->body.fn.fn_arg2, 3188 item->body.fn.fn_arg2); 3189 break; 3190 case NGQF_UNDEF: 3191 printf(" - UNDEFINED!\n"); 3192 } 3193 } 3194 if (line) { 3195 printf(" problem discovered at file %s, line %d\n", file, line); 3196 if (item->el_dest) { 3197 printf("node %p ([%x])\n", 3198 item->el_dest, ng_node2ID(item->el_dest)); 3199 } 3200 } 3201 } 3202 3203 static void 3204 ng_dumpitems(void) 3205 { 3206 item_p item; 3207 int i = 1; 3208 TAILQ_FOREACH(item, &ng_itemlist, all) { 3209 printf("[%d] ", i++); 3210 dumpitem(item, NULL, 0); 3211 } 3212 } 3213 3214 static void 3215 ng_dumpnodes(void) 3216 { 3217 node_p node; 3218 int i = 1; 3219 SLIST_FOREACH(node, &ng_allnodes, nd_all) { 3220 printf("[%d] ", i++); 3221 dumpnode(node, NULL, 0); 3222 } 3223 } 3224 3225 static void 3226 ng_dumphooks(void) 3227 { 3228 hook_p hook; 3229 int i = 1; 3230 SLIST_FOREACH(hook, &ng_allhooks, hk_all) { 3231 printf("[%d] ", i++); 3232 dumphook(hook, NULL, 0); 3233 } 3234 } 3235 3236 static int 3237 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS) 3238 { 3239 int error; 3240 int val; 3241 int i; 3242 3243 val = allocated; 3244 i = 1; 3245 error = sysctl_handle_int(oidp, &val, sizeof(int), req); 3246 if (error != 0 || req->newptr == NULL) 3247 return (error); 3248 if (val == 42) { 3249 ng_dumpitems(); 3250 ng_dumpnodes(); 3251 ng_dumphooks(); 3252 } 3253 return (0); 3254 } 3255 3256 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW, 3257 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items"); 3258 #endif /* NETGRAPH_DEBUG */ 3259 3260 3261 /*********************************************************************** 3262 * Worklist routines 3263 **********************************************************************/ 3264 /* NETISR thread enters here */ 3265 /* 3266 * Pick a node off the list of nodes with work, 3267 * try get an item to process off it. 3268 * If there are no more, remove the node from the list. 3269 */ 3270 static void 3271 ngintr(void) 3272 { 3273 item_p item; 3274 node_p node = NULL; 3275 3276 for (;;) { 3277 mtx_enter(&ng_worklist_mtx, MTX_SPIN); 3278 node = TAILQ_FIRST(&ng_worklist); 3279 if (!node) { 3280 mtx_exit(&ng_worklist_mtx, MTX_SPIN); 3281 break; 3282 } 3283 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3284 mtx_exit(&ng_worklist_mtx, MTX_SPIN); 3285 /* 3286 * We have the node. We also take over the reference 3287 * that the list had on it. 3288 * Now process as much as you can, until it won't 3289 * let you have another item off the queue. 3290 * All this time, keep the reference 3291 * that lets us be sure that the node still exists. 3292 * Let the reference go at the last minute. 3293 */ 3294 for (;;) { 3295 mtx_enter(&node->nd_input_queue.q_mtx, MTX_SPIN); 3296 item = ng_dequeue(&node->nd_input_queue); 3297 if (item == NULL) { 3298 /* 3299 * Say we are on the queue as long as 3300 * we are processing it here. 3301 * it probably wouldn't come here while we 3302 * are processing anyhow. 3303 */ 3304 node->nd_flags &= ~NG_WORKQ; 3305 mtx_exit(&node->nd_input_queue.q_mtx, MTX_SPIN); 3306 NG_NODE_UNREF(node); 3307 break; /* go look for another node */ 3308 } else { 3309 mtx_exit(&node->nd_input_queue.q_mtx, MTX_SPIN); 3310 #ifdef NETGRAPH_DEBUG 3311 _ngi_check(item, __FILE__, __LINE__); 3312 #endif 3313 ng_apply_item(node, item); 3314 } 3315 } 3316 } 3317 } 3318 3319 static void 3320 ng_worklist_remove(node_p node) 3321 { 3322 mtx_enter(&ng_worklist_mtx, MTX_SPIN); 3323 if (node->nd_flags & NG_WORKQ) { 3324 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3325 NG_NODE_UNREF(node); 3326 } 3327 node->nd_flags &= ~NG_WORKQ; 3328 mtx_exit(&ng_worklist_mtx, MTX_SPIN); 3329 } 3330 3331 static void 3332 ng_setisr(node_p node) 3333 { 3334 mtx_enter(&ng_worklist_mtx, MTX_SPIN); 3335 if ((node->nd_flags & NG_WORKQ) == 0) { 3336 /* 3337 * If we are not already on the work queue, 3338 * then put us on. 3339 */ 3340 node->nd_flags |= NG_WORKQ; 3341 TAILQ_INSERT_TAIL(&ng_worklist, node, nd_work); 3342 NG_NODE_REF(node); 3343 } 3344 mtx_exit(&ng_worklist_mtx, MTX_SPIN); 3345 schednetisr(NETISR_NETGRAPH); 3346 } 3347 3348 3349 /*********************************************************************** 3350 * Externally useable functions to set up a queue item ready for sending 3351 ***********************************************************************/ 3352 3353 #ifdef NETGRAPH_DEBUG 3354 #define ITEM_DEBUG_CHECKS \ 3355 do { \ 3356 if (item->el_dest ) { \ 3357 printf("item already has node"); \ 3358 Debugger("has node"); \ 3359 NG_NODE_UNREF(item->el_dest); \ 3360 item->el_dest = NULL; \ 3361 } \ 3362 if (item->el_hook ) { \ 3363 printf("item already has hook"); \ 3364 Debugger("has hook"); \ 3365 NG_HOOK_UNREF(item->el_hook); \ 3366 item->el_hook = NULL; \ 3367 } \ 3368 } while (0) 3369 #else 3370 #define ITEM_DEBUG_CHECKS 3371 #endif 3372 3373 /* 3374 * Put elements into the item. 3375 * Hook and node references will be removed when the item is dequeued. 3376 * (or equivalent) 3377 * (XXX) Unsafe because no reference held by peer on remote node. 3378 * remote node might go away in this timescale. 3379 * We know the hooks can't go away because that would require getting 3380 * a writer item on both nodes and we must have at least a reader 3381 * here to eb able to do this. 3382 * Note that the hook loaded is the REMOTE hook. 3383 * 3384 * This is possibly in the critical path for new data. 3385 */ 3386 item_p 3387 ng_package_data(struct mbuf *m, meta_p meta) 3388 { 3389 item_p item; 3390 3391 if ((item = ng_getqblk()) == NULL) { 3392 NG_FREE_M(m); 3393 NG_FREE_META(meta); 3394 return (NULL); 3395 } 3396 ITEM_DEBUG_CHECKS; 3397 item->el_flags = NGQF_DATA; 3398 item->el_next = NULL; 3399 NGI_M(item) = m; 3400 NGI_META(item) = meta; 3401 return (item); 3402 } 3403 3404 /* 3405 * Allocate a queue item and put items into it.. 3406 * Evaluate the address as this will be needed to queue it and 3407 * to work out what some of the fields should be. 3408 * Hook and node references will be removed when the item is dequeued. 3409 * (or equivalent) 3410 */ 3411 item_p 3412 ng_package_msg(struct ng_mesg *msg) 3413 { 3414 item_p item; 3415 3416 if ((item = ng_getqblk()) == NULL) { 3417 if ((msg->header.flags & NGF_STATIC) == 0) { 3418 NG_FREE_MSG(msg); 3419 } 3420 return (NULL); 3421 } 3422 ITEM_DEBUG_CHECKS; 3423 item->el_flags = NGQF_MESG; 3424 item->el_next = NULL; 3425 /* 3426 * Set the current lasthook into the queue item 3427 */ 3428 NGI_MSG(item) = msg; 3429 NGI_RETADDR(item) = NULL; 3430 return (item); 3431 } 3432 3433 3434 3435 #define SET_RETADDR \ 3436 do { /* Data or fn items don't have retaddrs */ \ 3437 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \ 3438 if (retaddr) { \ 3439 NGI_RETADDR(item) = retaddr; \ 3440 } else { \ 3441 /* \ 3442 * The old return address should be ok. \ 3443 * If there isn't one, use the address \ 3444 * here. \ 3445 */ \ 3446 if (NGI_RETADDR(item) == 0) { \ 3447 NGI_RETADDR(item) \ 3448 = ng_node2ID(here); \ 3449 } \ 3450 } \ 3451 } \ 3452 } while (0) 3453 3454 int 3455 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr) 3456 { 3457 ITEM_DEBUG_CHECKS; 3458 /* 3459 * Quick sanity check.. 3460 * Since a hook holds a reference on it's node, once we know 3461 * that the peer is still connected (even if invalid,) we know 3462 * that the peer node is present, though maybe invalid. 3463 */ 3464 if ((hook == NULL) 3465 || NG_HOOK_NOT_VALID(hook) 3466 || (NG_HOOK_PEER(hook) == NULL) 3467 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)) 3468 || NG_NODE_NOT_VALID(NG_PEER_NODE(hook))) { 3469 NG_FREE_ITEM(item); 3470 TRAP_ERROR(); 3471 return (EINVAL); 3472 } 3473 3474 /* 3475 * Transfer our interest to the other (peer) end. 3476 */ 3477 item->el_hook = NG_HOOK_PEER(hook); 3478 NG_HOOK_REF(item->el_hook); /* Don't let it go while on the queue */ 3479 item->el_dest = NG_PEER_NODE(hook); 3480 NG_NODE_REF(item->el_dest); /* Nor this */ 3481 SET_RETADDR; 3482 return (0); 3483 } 3484 3485 int 3486 ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr) 3487 { 3488 node_p dest = NULL; 3489 hook_p hook = NULL; 3490 int error; 3491 3492 ITEM_DEBUG_CHECKS; 3493 /* 3494 * Note that ng_path2noderef increments the reference count 3495 * on the node for us if it finds one. So we don't have to. 3496 */ 3497 error = ng_path2noderef(here, address, &dest, &hook); 3498 if (error) { 3499 NG_FREE_ITEM(item); 3500 return (error); 3501 } 3502 item->el_dest = dest; 3503 if (( item->el_hook = hook)) 3504 NG_HOOK_REF(hook); /* don't let it go while on the queue */ 3505 SET_RETADDR; 3506 return (0); 3507 } 3508 3509 int 3510 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr) 3511 { 3512 node_p dest; 3513 3514 ITEM_DEBUG_CHECKS; 3515 /* 3516 * Find the target node. 3517 */ 3518 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */ 3519 if (dest == NULL) { 3520 NG_FREE_ITEM(item); 3521 TRAP_ERROR(); 3522 return(EINVAL); 3523 } 3524 /* Fill out the contents */ 3525 item->el_flags = NGQF_MESG; 3526 item->el_next = NULL; 3527 item->el_dest = dest; 3528 item->el_hook = NULL; 3529 SET_RETADDR; 3530 return (0); 3531 } 3532 3533 /* 3534 * special case to send a message to self (e.g. destroy node) 3535 * Possibly indicate an arrival hook too. 3536 * Useful for removing that hook :-) 3537 */ 3538 item_p 3539 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg) 3540 { 3541 item_p item; 3542 3543 /* 3544 * Find the target node. 3545 * If there is a HOOK argument, then use that in preference 3546 * to the address. 3547 */ 3548 if ((item = ng_getqblk()) == NULL) { 3549 if ((msg->header.flags & NGF_STATIC) == 0) { 3550 NG_FREE_MSG(msg); 3551 } 3552 return (NULL); 3553 } 3554 3555 /* Fill out the contents */ 3556 item->el_flags = NGQF_MESG; 3557 item->el_next = NULL; 3558 item->el_dest = here; 3559 NG_NODE_REF(here); 3560 item->el_hook = hook; 3561 if (hook) 3562 NG_HOOK_REF(hook); 3563 NGI_MSG(item) = msg; 3564 NGI_RETADDR(item) = ng_node2ID(here); 3565 return (item); 3566 } 3567 3568 int 3569 ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2) 3570 { 3571 item_p item; 3572 3573 if ((item = ng_getqblk()) == NULL) { 3574 return (ENOMEM); 3575 } 3576 item->el_flags = NGQF_FN | NGQF_WRITER; 3577 item->el_dest = node; 3578 NG_NODE_REF(node); 3579 if ((item->el_hook = hook)) { 3580 NG_HOOK_REF(hook); 3581 } 3582 NGI_FN(item) = fn; 3583 NGI_ARG1(item) = arg1; 3584 NGI_ARG2(item) = arg2; 3585 return (ng_snd_item(item, 0)); 3586 } 3587 3588 /* 3589 * Set the address, if none given, give the node here. 3590 */ 3591 void 3592 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr) 3593 { 3594 if (retaddr) { 3595 NGI_RETADDR(item) = retaddr; 3596 } else { 3597 /* 3598 * The old return address should be ok. 3599 * If there isn't one, use the address here. 3600 */ 3601 NGI_RETADDR(item) = ng_node2ID(here); 3602 } 3603 } 3604 3605 #define TESTING 3606 #ifdef TESTING 3607 /* just test all the macros */ 3608 void 3609 ng_macro_test(item_p item); 3610 void 3611 ng_macro_test(item_p item) 3612 { 3613 node_p node = NULL; 3614 hook_p hook = NULL; 3615 struct mbuf *m; 3616 meta_p meta; 3617 struct ng_mesg *msg; 3618 ng_ID_t retaddr; 3619 int error; 3620 3621 NGI_GET_M(item, m); 3622 NGI_GET_META(item, meta); 3623 NGI_GET_MSG(item, msg); 3624 retaddr = NGI_RETADDR(item); 3625 NG_SEND_DATA(error, hook, m, meta); 3626 NG_SEND_DATA_ONLY(error, hook, m); 3627 NG_FWD_NEW_DATA(error, item, hook, m); 3628 NG_FWD_ITEM_HOOK(error, item, hook); 3629 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr); 3630 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr); 3631 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr); 3632 NG_QUEUE_MSG(error, node, msg, ".:", retaddr); 3633 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr); 3634 } 3635 #endif /* TESTING */ 3636 3637