ng_base.c revision 177722
1/* 2 * ng_base.c 3 */ 4 5/*- 6 * Copyright (c) 1996-1999 Whistle Communications, Inc. 7 * All rights reserved. 8 * 9 * Subject to the following obligations and disclaimer of warranty, use and 10 * redistribution of this software, in source or object code forms, with or 11 * without modifications are expressly permitted by Whistle Communications; 12 * provided, however, that: 13 * 1. Any and all reproductions of the source or object code must include the 14 * copyright notice above and the following disclaimer of warranties; and 15 * 2. No rights are granted, in any manner or form, to use Whistle 16 * Communications, Inc. trademarks, including the mark "WHISTLE 17 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 18 * such appears in the above copyright notice or in the software. 19 * 20 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 21 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 22 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 23 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 25 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 26 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 27 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 28 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 29 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 30 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 31 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 32 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 35 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 36 * OF SUCH DAMAGE. 37 * 38 * Authors: Julian Elischer <julian@freebsd.org> 39 * Archie Cobbs <archie@freebsd.org> 40 * 41 * $FreeBSD: head/sys/netgraph/ng_base.c 177722 2008-03-29 22:53:58Z mav $ 42 * $Whistle: ng_base.c,v 1.39 1999/01/28 23:54:53 julian Exp $ 43 */ 44 45/* 46 * This file implements the base netgraph code. 47 */ 48 49#include <sys/param.h> 50#include <sys/systm.h> 51#include <sys/ctype.h> 52#include <sys/errno.h> 53#include <sys/kdb.h> 54#include <sys/kernel.h> 55#include <sys/ktr.h> 56#include <sys/limits.h> 57#include <sys/malloc.h> 58#include <sys/mbuf.h> 59#include <sys/queue.h> 60#include <sys/sysctl.h> 61#include <sys/syslog.h> 62#include <sys/refcount.h> 63#include <sys/proc.h> 64 65#include <net/netisr.h> 66 67#include <netgraph/ng_message.h> 68#include <netgraph/netgraph.h> 69#include <netgraph/ng_parse.h> 70 71MODULE_VERSION(netgraph, NG_ABI_VERSION); 72 73/* Mutex to protect topology events. */ 74static struct mtx ng_topo_mtx; 75 76#ifdef NETGRAPH_DEBUG 77static struct mtx ng_nodelist_mtx; /* protects global node/hook lists */ 78static struct mtx ngq_mtx; /* protects the queue item list */ 79 80static SLIST_HEAD(, ng_node) ng_allnodes; 81static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */ 82static SLIST_HEAD(, ng_hook) ng_allhooks; 83static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */ 84 85static void ng_dumpitems(void); 86static void ng_dumpnodes(void); 87static void ng_dumphooks(void); 88 89#endif /* NETGRAPH_DEBUG */ 90/* 91 * DEAD versions of the structures. 92 * In order to avoid races, it is sometimes neccesary to point 93 * at SOMETHING even though theoretically, the current entity is 94 * INVALID. Use these to avoid these races. 95 */ 96struct ng_type ng_deadtype = { 97 NG_ABI_VERSION, 98 "dead", 99 NULL, /* modevent */ 100 NULL, /* constructor */ 101 NULL, /* rcvmsg */ 102 NULL, /* shutdown */ 103 NULL, /* newhook */ 104 NULL, /* findhook */ 105 NULL, /* connect */ 106 NULL, /* rcvdata */ 107 NULL, /* disconnect */ 108 NULL, /* cmdlist */ 109}; 110 111struct ng_node ng_deadnode = { 112 "dead", 113 &ng_deadtype, 114 NGF_INVALID, 115 1, /* refs */ 116 0, /* numhooks */ 117 NULL, /* private */ 118 0, /* ID */ 119 LIST_HEAD_INITIALIZER(ng_deadnode.hooks), 120 {}, /* all_nodes list entry */ 121 {}, /* id hashtable list entry */ 122 {}, /* workqueue entry */ 123 { 0, 124 {}, /* should never use! (should hang) */ 125 NULL, 126 &ng_deadnode.nd_input_queue.queue, 127 &ng_deadnode 128 }, 129#ifdef NETGRAPH_DEBUG 130 ND_MAGIC, 131 __FILE__, 132 __LINE__, 133 {NULL} 134#endif /* NETGRAPH_DEBUG */ 135}; 136 137struct ng_hook ng_deadhook = { 138 "dead", 139 NULL, /* private */ 140 HK_INVALID | HK_DEAD, 141 1, /* refs always >= 1 */ 142 0, /* undefined data link type */ 143 &ng_deadhook, /* Peer is self */ 144 &ng_deadnode, /* attached to deadnode */ 145 {}, /* hooks list */ 146 NULL, /* override rcvmsg() */ 147 NULL, /* override rcvdata() */ 148#ifdef NETGRAPH_DEBUG 149 HK_MAGIC, 150 __FILE__, 151 __LINE__, 152 {NULL} 153#endif /* NETGRAPH_DEBUG */ 154}; 155 156/* 157 * END DEAD STRUCTURES 158 */ 159/* List nodes with unallocated work */ 160static TAILQ_HEAD(, ng_node) ng_worklist = TAILQ_HEAD_INITIALIZER(ng_worklist); 161static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */ 162 163/* List of installed types */ 164static LIST_HEAD(, ng_type) ng_typelist; 165static struct mtx ng_typelist_mtx; 166 167/* Hash related definitions */ 168/* XXX Don't need to initialise them because it's a LIST */ 169#define NG_ID_HASH_SIZE 128 /* most systems wont need even this many */ 170static LIST_HEAD(, ng_node) ng_ID_hash[NG_ID_HASH_SIZE]; 171static struct mtx ng_idhash_mtx; 172/* Method to find a node.. used twice so do it here */ 173#define NG_IDHASH_FN(ID) ((ID) % (NG_ID_HASH_SIZE)) 174#define NG_IDHASH_FIND(ID, node) \ 175 do { \ 176 mtx_assert(&ng_idhash_mtx, MA_OWNED); \ 177 LIST_FOREACH(node, &ng_ID_hash[NG_IDHASH_FN(ID)], \ 178 nd_idnodes) { \ 179 if (NG_NODE_IS_VALID(node) \ 180 && (NG_NODE_ID(node) == ID)) { \ 181 break; \ 182 } \ 183 } \ 184 } while (0) 185 186#define NG_NAME_HASH_SIZE 128 /* most systems wont need even this many */ 187static LIST_HEAD(, ng_node) ng_name_hash[NG_NAME_HASH_SIZE]; 188static struct mtx ng_namehash_mtx; 189#define NG_NAMEHASH(NAME, HASH) \ 190 do { \ 191 u_char h = 0; \ 192 const u_char *c; \ 193 for (c = (const u_char*)(NAME); *c; c++)\ 194 h += *c; \ 195 (HASH) = h % (NG_NAME_HASH_SIZE); \ 196 } while (0) 197 198 199/* Internal functions */ 200static int ng_add_hook(node_p node, const char *name, hook_p * hookp); 201static int ng_generic_msg(node_p here, item_p item, hook_p lasthook); 202static ng_ID_t ng_decodeidname(const char *name); 203static int ngb_mod_event(module_t mod, int event, void *data); 204static void ng_worklist_remove(node_p node); 205static void ngintr(void); 206static int ng_apply_item(node_p node, item_p item, int rw); 207static void ng_flush_input_queue(struct ng_queue * ngq); 208static void ng_setisr(node_p node); 209static node_p ng_ID2noderef(ng_ID_t ID); 210static int ng_con_nodes(item_p item, node_p node, const char *name, 211 node_p node2, const char *name2); 212static int ng_con_part2(node_p node, item_p item, hook_p hook); 213static int ng_con_part3(node_p node, item_p item, hook_p hook); 214static int ng_mkpeer(node_p node, const char *name, 215 const char *name2, char *type); 216 217/* Imported, these used to be externally visible, some may go back. */ 218void ng_destroy_hook(hook_p hook); 219node_p ng_name2noderef(node_p node, const char *name); 220int ng_path2noderef(node_p here, const char *path, 221 node_p *dest, hook_p *lasthook); 222int ng_make_node(const char *type, node_p *nodepp); 223int ng_path_parse(char *addr, char **node, char **path, char **hook); 224void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3); 225void ng_unname(node_p node); 226 227 228/* Our own netgraph malloc type */ 229MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages"); 230MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures"); 231MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures"); 232MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", "netgraph item structures"); 233MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage"); 234 235/* Should not be visible outside this file */ 236 237#define _NG_ALLOC_HOOK(hook) \ 238 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO) 239#define _NG_ALLOC_NODE(node) \ 240 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO) 241 242#define NG_QUEUE_LOCK_INIT(n) \ 243 mtx_init(&(n)->q_mtx, "ng_node", NULL, MTX_DEF) 244#define NG_QUEUE_LOCK(n) \ 245 mtx_lock(&(n)->q_mtx) 246#define NG_QUEUE_UNLOCK(n) \ 247 mtx_unlock(&(n)->q_mtx) 248#define NG_WORKLIST_LOCK_INIT() \ 249 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_DEF) 250#define NG_WORKLIST_LOCK() \ 251 mtx_lock(&ng_worklist_mtx) 252#define NG_WORKLIST_UNLOCK() \ 253 mtx_unlock(&ng_worklist_mtx) 254 255#ifdef NETGRAPH_DEBUG /*----------------------------------------------*/ 256/* 257 * In debug mode: 258 * In an attempt to help track reference count screwups 259 * we do not free objects back to the malloc system, but keep them 260 * in a local cache where we can examine them and keep information safely 261 * after they have been freed. 262 * We use this scheme for nodes and hooks, and to some extent for items. 263 */ 264static __inline hook_p 265ng_alloc_hook(void) 266{ 267 hook_p hook; 268 SLIST_ENTRY(ng_hook) temp; 269 mtx_lock(&ng_nodelist_mtx); 270 hook = LIST_FIRST(&ng_freehooks); 271 if (hook) { 272 LIST_REMOVE(hook, hk_hooks); 273 bcopy(&hook->hk_all, &temp, sizeof(temp)); 274 bzero(hook, sizeof(struct ng_hook)); 275 bcopy(&temp, &hook->hk_all, sizeof(temp)); 276 mtx_unlock(&ng_nodelist_mtx); 277 hook->hk_magic = HK_MAGIC; 278 } else { 279 mtx_unlock(&ng_nodelist_mtx); 280 _NG_ALLOC_HOOK(hook); 281 if (hook) { 282 hook->hk_magic = HK_MAGIC; 283 mtx_lock(&ng_nodelist_mtx); 284 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all); 285 mtx_unlock(&ng_nodelist_mtx); 286 } 287 } 288 return (hook); 289} 290 291static __inline node_p 292ng_alloc_node(void) 293{ 294 node_p node; 295 SLIST_ENTRY(ng_node) temp; 296 mtx_lock(&ng_nodelist_mtx); 297 node = LIST_FIRST(&ng_freenodes); 298 if (node) { 299 LIST_REMOVE(node, nd_nodes); 300 bcopy(&node->nd_all, &temp, sizeof(temp)); 301 bzero(node, sizeof(struct ng_node)); 302 bcopy(&temp, &node->nd_all, sizeof(temp)); 303 mtx_unlock(&ng_nodelist_mtx); 304 node->nd_magic = ND_MAGIC; 305 } else { 306 mtx_unlock(&ng_nodelist_mtx); 307 _NG_ALLOC_NODE(node); 308 if (node) { 309 node->nd_magic = ND_MAGIC; 310 mtx_lock(&ng_nodelist_mtx); 311 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all); 312 mtx_unlock(&ng_nodelist_mtx); 313 } 314 } 315 return (node); 316} 317 318#define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0) 319#define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0) 320 321 322#define NG_FREE_HOOK(hook) \ 323 do { \ 324 mtx_lock(&ng_nodelist_mtx); \ 325 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \ 326 hook->hk_magic = 0; \ 327 mtx_unlock(&ng_nodelist_mtx); \ 328 } while (0) 329 330#define NG_FREE_NODE(node) \ 331 do { \ 332 mtx_lock(&ng_nodelist_mtx); \ 333 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \ 334 node->nd_magic = 0; \ 335 mtx_unlock(&ng_nodelist_mtx); \ 336 } while (0) 337 338#else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 339 340#define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook) 341#define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node) 342 343#define NG_FREE_HOOK(hook) do { FREE((hook), M_NETGRAPH_HOOK); } while (0) 344#define NG_FREE_NODE(node) do { FREE((node), M_NETGRAPH_NODE); } while (0) 345 346#endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 347 348/* Set this to kdb_enter("X") to catch all errors as they occur */ 349#ifndef TRAP_ERROR 350#define TRAP_ERROR() 351#endif 352 353static ng_ID_t nextID = 1; 354 355#ifdef INVARIANTS 356#define CHECK_DATA_MBUF(m) do { \ 357 struct mbuf *n; \ 358 int total; \ 359 \ 360 M_ASSERTPKTHDR(m); \ 361 for (total = 0, n = (m); n != NULL; n = n->m_next) { \ 362 total += n->m_len; \ 363 if (n->m_nextpkt != NULL) \ 364 panic("%s: m_nextpkt", __func__); \ 365 } \ 366 \ 367 if ((m)->m_pkthdr.len != total) { \ 368 panic("%s: %d != %d", \ 369 __func__, (m)->m_pkthdr.len, total); \ 370 } \ 371 } while (0) 372#else 373#define CHECK_DATA_MBUF(m) 374#endif 375 376#define ERROUT(x) do { error = (x); goto done; } while (0) 377 378/************************************************************************ 379 Parse type definitions for generic messages 380************************************************************************/ 381 382/* Handy structure parse type defining macro */ 383#define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \ 384static const struct ng_parse_struct_field \ 385 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \ 386static const struct ng_parse_type ng_generic_ ## lo ## _type = { \ 387 &ng_parse_struct_type, \ 388 &ng_ ## lo ## _type_fields \ 389} 390 391DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ()); 392DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ()); 393DEFINE_PARSE_STRUCT_TYPE(name, NAME, ()); 394DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ()); 395DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ()); 396DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ()); 397DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type)); 398 399/* Get length of an array when the length is stored as a 32 bit 400 value immediately preceding the array -- as with struct namelist 401 and struct typelist. */ 402static int 403ng_generic_list_getLength(const struct ng_parse_type *type, 404 const u_char *start, const u_char *buf) 405{ 406 return *((const u_int32_t *)(buf - 4)); 407} 408 409/* Get length of the array of struct linkinfo inside a struct hooklist */ 410static int 411ng_generic_linkinfo_getLength(const struct ng_parse_type *type, 412 const u_char *start, const u_char *buf) 413{ 414 const struct hooklist *hl = (const struct hooklist *)start; 415 416 return hl->nodeinfo.hooks; 417} 418 419/* Array type for a variable length array of struct namelist */ 420static const struct ng_parse_array_info ng_nodeinfoarray_type_info = { 421 &ng_generic_nodeinfo_type, 422 &ng_generic_list_getLength 423}; 424static const struct ng_parse_type ng_generic_nodeinfoarray_type = { 425 &ng_parse_array_type, 426 &ng_nodeinfoarray_type_info 427}; 428 429/* Array type for a variable length array of struct typelist */ 430static const struct ng_parse_array_info ng_typeinfoarray_type_info = { 431 &ng_generic_typeinfo_type, 432 &ng_generic_list_getLength 433}; 434static const struct ng_parse_type ng_generic_typeinfoarray_type = { 435 &ng_parse_array_type, 436 &ng_typeinfoarray_type_info 437}; 438 439/* Array type for array of struct linkinfo in struct hooklist */ 440static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = { 441 &ng_generic_linkinfo_type, 442 &ng_generic_linkinfo_getLength 443}; 444static const struct ng_parse_type ng_generic_linkinfo_array_type = { 445 &ng_parse_array_type, 446 &ng_generic_linkinfo_array_type_info 447}; 448 449DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type)); 450DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST, 451 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type)); 452DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES, 453 (&ng_generic_nodeinfoarray_type)); 454 455/* List of commands and how to convert arguments to/from ASCII */ 456static const struct ng_cmdlist ng_generic_cmds[] = { 457 { 458 NGM_GENERIC_COOKIE, 459 NGM_SHUTDOWN, 460 "shutdown", 461 NULL, 462 NULL 463 }, 464 { 465 NGM_GENERIC_COOKIE, 466 NGM_MKPEER, 467 "mkpeer", 468 &ng_generic_mkpeer_type, 469 NULL 470 }, 471 { 472 NGM_GENERIC_COOKIE, 473 NGM_CONNECT, 474 "connect", 475 &ng_generic_connect_type, 476 NULL 477 }, 478 { 479 NGM_GENERIC_COOKIE, 480 NGM_NAME, 481 "name", 482 &ng_generic_name_type, 483 NULL 484 }, 485 { 486 NGM_GENERIC_COOKIE, 487 NGM_RMHOOK, 488 "rmhook", 489 &ng_generic_rmhook_type, 490 NULL 491 }, 492 { 493 NGM_GENERIC_COOKIE, 494 NGM_NODEINFO, 495 "nodeinfo", 496 NULL, 497 &ng_generic_nodeinfo_type 498 }, 499 { 500 NGM_GENERIC_COOKIE, 501 NGM_LISTHOOKS, 502 "listhooks", 503 NULL, 504 &ng_generic_hooklist_type 505 }, 506 { 507 NGM_GENERIC_COOKIE, 508 NGM_LISTNAMES, 509 "listnames", 510 NULL, 511 &ng_generic_listnodes_type /* same as NGM_LISTNODES */ 512 }, 513 { 514 NGM_GENERIC_COOKIE, 515 NGM_LISTNODES, 516 "listnodes", 517 NULL, 518 &ng_generic_listnodes_type 519 }, 520 { 521 NGM_GENERIC_COOKIE, 522 NGM_LISTTYPES, 523 "listtypes", 524 NULL, 525 &ng_generic_typeinfo_type 526 }, 527 { 528 NGM_GENERIC_COOKIE, 529 NGM_TEXT_CONFIG, 530 "textconfig", 531 NULL, 532 &ng_parse_string_type 533 }, 534 { 535 NGM_GENERIC_COOKIE, 536 NGM_TEXT_STATUS, 537 "textstatus", 538 NULL, 539 &ng_parse_string_type 540 }, 541 { 542 NGM_GENERIC_COOKIE, 543 NGM_ASCII2BINARY, 544 "ascii2binary", 545 &ng_parse_ng_mesg_type, 546 &ng_parse_ng_mesg_type 547 }, 548 { 549 NGM_GENERIC_COOKIE, 550 NGM_BINARY2ASCII, 551 "binary2ascii", 552 &ng_parse_ng_mesg_type, 553 &ng_parse_ng_mesg_type 554 }, 555 { 0 } 556}; 557 558/************************************************************************ 559 Node routines 560************************************************************************/ 561 562/* 563 * Instantiate a node of the requested type 564 */ 565int 566ng_make_node(const char *typename, node_p *nodepp) 567{ 568 struct ng_type *type; 569 int error; 570 571 /* Check that the type makes sense */ 572 if (typename == NULL) { 573 TRAP_ERROR(); 574 return (EINVAL); 575 } 576 577 /* Locate the node type. If we fail we return. Do not try to load 578 * module. 579 */ 580 if ((type = ng_findtype(typename)) == NULL) 581 return (ENXIO); 582 583 /* 584 * If we have a constructor, then make the node and 585 * call the constructor to do type specific initialisation. 586 */ 587 if (type->constructor != NULL) { 588 if ((error = ng_make_node_common(type, nodepp)) == 0) { 589 if ((error = ((*type->constructor)(*nodepp)) != 0)) { 590 NG_NODE_UNREF(*nodepp); 591 } 592 } 593 } else { 594 /* 595 * Node has no constructor. We cannot ask for one 596 * to be made. It must be brought into existence by 597 * some external agency. The external agency should 598 * call ng_make_node_common() directly to get the 599 * netgraph part initialised. 600 */ 601 TRAP_ERROR(); 602 error = EINVAL; 603 } 604 return (error); 605} 606 607/* 608 * Generic node creation. Called by node initialisation for externally 609 * instantiated nodes (e.g. hardware, sockets, etc ). 610 * The returned node has a reference count of 1. 611 */ 612int 613ng_make_node_common(struct ng_type *type, node_p *nodepp) 614{ 615 node_p node; 616 617 /* Require the node type to have been already installed */ 618 if (ng_findtype(type->name) == NULL) { 619 TRAP_ERROR(); 620 return (EINVAL); 621 } 622 623 /* Make a node and try attach it to the type */ 624 NG_ALLOC_NODE(node); 625 if (node == NULL) { 626 TRAP_ERROR(); 627 return (ENOMEM); 628 } 629 node->nd_type = type; 630 NG_NODE_REF(node); /* note reference */ 631 type->refs++; 632 633 NG_QUEUE_LOCK_INIT(&node->nd_input_queue); 634 node->nd_input_queue.queue = NULL; 635 node->nd_input_queue.last = &node->nd_input_queue.queue; 636 node->nd_input_queue.q_flags = 0; 637 node->nd_input_queue.q_node = node; 638 639 /* Initialize hook list for new node */ 640 LIST_INIT(&node->nd_hooks); 641 642 /* Link us into the name hash. */ 643 mtx_lock(&ng_namehash_mtx); 644 LIST_INSERT_HEAD(&ng_name_hash[0], node, nd_nodes); 645 mtx_unlock(&ng_namehash_mtx); 646 647 /* get an ID and put us in the hash chain */ 648 mtx_lock(&ng_idhash_mtx); 649 for (;;) { /* wrap protection, even if silly */ 650 node_p node2 = NULL; 651 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */ 652 653 /* Is there a problem with the new number? */ 654 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */ 655 if ((node->nd_ID != 0) && (node2 == NULL)) { 656 break; 657 } 658 } 659 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)], 660 node, nd_idnodes); 661 mtx_unlock(&ng_idhash_mtx); 662 663 /* Done */ 664 *nodepp = node; 665 return (0); 666} 667 668/* 669 * Forceably start the shutdown process on a node. Either call 670 * its shutdown method, or do the default shutdown if there is 671 * no type-specific method. 672 * 673 * We can only be called from a shutdown message, so we know we have 674 * a writer lock, and therefore exclusive access. It also means 675 * that we should not be on the work queue, but we check anyhow. 676 * 677 * Persistent node types must have a type-specific method which 678 * allocates a new node in which case, this one is irretrievably going away, 679 * or cleans up anything it needs, and just makes the node valid again, 680 * in which case we allow the node to survive. 681 * 682 * XXX We need to think of how to tell a persistent node that we 683 * REALLY need to go away because the hardware has gone or we 684 * are rebooting.... etc. 685 */ 686void 687ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3) 688{ 689 hook_p hook; 690 691 /* Check if it's already shutting down */ 692 if ((node->nd_flags & NGF_CLOSING) != 0) 693 return; 694 695 if (node == &ng_deadnode) { 696 printf ("shutdown called on deadnode\n"); 697 return; 698 } 699 700 /* Add an extra reference so it doesn't go away during this */ 701 NG_NODE_REF(node); 702 703 /* 704 * Mark it invalid so any newcomers know not to try use it 705 * Also add our own mark so we can't recurse 706 * note that NGF_INVALID does not do this as it's also set during 707 * creation 708 */ 709 node->nd_flags |= NGF_INVALID|NGF_CLOSING; 710 711 /* If node has its pre-shutdown method, then call it first*/ 712 if (node->nd_type && node->nd_type->close) 713 (*node->nd_type->close)(node); 714 715 /* Notify all remaining connected nodes to disconnect */ 716 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL) 717 ng_destroy_hook(hook); 718 719 /* 720 * Drain the input queue forceably. 721 * it has no hooks so what's it going to do, bleed on someone? 722 * Theoretically we came here from a queue entry that was added 723 * Just before the queue was closed, so it should be empty anyway. 724 * Also removes us from worklist if needed. 725 */ 726 ng_flush_input_queue(&node->nd_input_queue); 727 728 /* Ask the type if it has anything to do in this case */ 729 if (node->nd_type && node->nd_type->shutdown) { 730 (*node->nd_type->shutdown)(node); 731 if (NG_NODE_IS_VALID(node)) { 732 /* 733 * Well, blow me down if the node code hasn't declared 734 * that it doesn't want to die. 735 * Presumably it is a persistant node. 736 * If we REALLY want it to go away, 737 * e.g. hardware going away, 738 * Our caller should set NGF_REALLY_DIE in nd_flags. 739 */ 740 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING); 741 NG_NODE_UNREF(node); /* Assume they still have theirs */ 742 return; 743 } 744 } else { /* do the default thing */ 745 NG_NODE_UNREF(node); 746 } 747 748 ng_unname(node); /* basically a NOP these days */ 749 750 /* 751 * Remove extra reference, possibly the last 752 * Possible other holders of references may include 753 * timeout callouts, but theoretically the node's supposed to 754 * have cancelled them. Possibly hardware dependencies may 755 * force a driver to 'linger' with a reference. 756 */ 757 NG_NODE_UNREF(node); 758} 759 760/* 761 * Remove a reference to the node, possibly the last. 762 * deadnode always acts as it it were the last. 763 */ 764int 765ng_unref_node(node_p node) 766{ 767 int v; 768 769 if (node == &ng_deadnode) { 770 return (0); 771 } 772 773 do { 774 v = node->nd_refs - 1; 775 } while (! atomic_cmpset_int(&node->nd_refs, v + 1, v)); 776 777 if (v == 0) { /* we were the last */ 778 779 mtx_lock(&ng_namehash_mtx); 780 node->nd_type->refs--; /* XXX maybe should get types lock? */ 781 LIST_REMOVE(node, nd_nodes); 782 mtx_unlock(&ng_namehash_mtx); 783 784 mtx_lock(&ng_idhash_mtx); 785 LIST_REMOVE(node, nd_idnodes); 786 mtx_unlock(&ng_idhash_mtx); 787 788 mtx_destroy(&node->nd_input_queue.q_mtx); 789 NG_FREE_NODE(node); 790 } 791 return (v); 792} 793 794/************************************************************************ 795 Node ID handling 796************************************************************************/ 797static node_p 798ng_ID2noderef(ng_ID_t ID) 799{ 800 node_p node; 801 mtx_lock(&ng_idhash_mtx); 802 NG_IDHASH_FIND(ID, node); 803 if(node) 804 NG_NODE_REF(node); 805 mtx_unlock(&ng_idhash_mtx); 806 return(node); 807} 808 809ng_ID_t 810ng_node2ID(node_p node) 811{ 812 return (node ? NG_NODE_ID(node) : 0); 813} 814 815/************************************************************************ 816 Node name handling 817************************************************************************/ 818 819/* 820 * Assign a node a name. Once assigned, the name cannot be changed. 821 */ 822int 823ng_name_node(node_p node, const char *name) 824{ 825 int i, hash; 826 node_p node2; 827 828 /* Check the name is valid */ 829 for (i = 0; i < NG_NODESIZ; i++) { 830 if (name[i] == '\0' || name[i] == '.' || name[i] == ':') 831 break; 832 } 833 if (i == 0 || name[i] != '\0') { 834 TRAP_ERROR(); 835 return (EINVAL); 836 } 837 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */ 838 TRAP_ERROR(); 839 return (EINVAL); 840 } 841 842 /* Check the name isn't already being used */ 843 if ((node2 = ng_name2noderef(node, name)) != NULL) { 844 NG_NODE_UNREF(node2); 845 TRAP_ERROR(); 846 return (EADDRINUSE); 847 } 848 849 /* copy it */ 850 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ); 851 852 /* Update name hash. */ 853 NG_NAMEHASH(name, hash); 854 mtx_lock(&ng_namehash_mtx); 855 LIST_REMOVE(node, nd_nodes); 856 LIST_INSERT_HEAD(&ng_name_hash[hash], node, nd_nodes); 857 mtx_unlock(&ng_namehash_mtx); 858 859 return (0); 860} 861 862/* 863 * Find a node by absolute name. The name should NOT end with ':' 864 * The name "." means "this node" and "[xxx]" means "the node 865 * with ID (ie, at address) xxx". 866 * 867 * Returns the node if found, else NULL. 868 * Eventually should add something faster than a sequential search. 869 * Note it acquires a reference on the node so you can be sure it's still 870 * there. 871 */ 872node_p 873ng_name2noderef(node_p here, const char *name) 874{ 875 node_p node; 876 ng_ID_t temp; 877 int hash; 878 879 /* "." means "this node" */ 880 if (strcmp(name, ".") == 0) { 881 NG_NODE_REF(here); 882 return(here); 883 } 884 885 /* Check for name-by-ID */ 886 if ((temp = ng_decodeidname(name)) != 0) { 887 return (ng_ID2noderef(temp)); 888 } 889 890 /* Find node by name */ 891 NG_NAMEHASH(name, hash); 892 mtx_lock(&ng_namehash_mtx); 893 LIST_FOREACH(node, &ng_name_hash[hash], nd_nodes) { 894 if (NG_NODE_IS_VALID(node) && 895 (strcmp(NG_NODE_NAME(node), name) == 0)) { 896 break; 897 } 898 } 899 if (node) 900 NG_NODE_REF(node); 901 mtx_unlock(&ng_namehash_mtx); 902 return (node); 903} 904 905/* 906 * Decode an ID name, eg. "[f03034de]". Returns 0 if the 907 * string is not valid, otherwise returns the value. 908 */ 909static ng_ID_t 910ng_decodeidname(const char *name) 911{ 912 const int len = strlen(name); 913 char *eptr; 914 u_long val; 915 916 /* Check for proper length, brackets, no leading junk */ 917 if ((len < 3) 918 || (name[0] != '[') 919 || (name[len - 1] != ']') 920 || (!isxdigit(name[1]))) { 921 return ((ng_ID_t)0); 922 } 923 924 /* Decode number */ 925 val = strtoul(name + 1, &eptr, 16); 926 if ((eptr - name != len - 1) 927 || (val == ULONG_MAX) 928 || (val == 0)) { 929 return ((ng_ID_t)0); 930 } 931 return (ng_ID_t)val; 932} 933 934/* 935 * Remove a name from a node. This should only be called 936 * when shutting down and removing the node. 937 * IF we allow name changing this may be more resurrected. 938 */ 939void 940ng_unname(node_p node) 941{ 942} 943 944/************************************************************************ 945 Hook routines 946 Names are not optional. Hooks are always connected, except for a 947 brief moment within these routines. On invalidation or during creation 948 they are connected to the 'dead' hook. 949************************************************************************/ 950 951/* 952 * Remove a hook reference 953 */ 954void 955ng_unref_hook(hook_p hook) 956{ 957 int v; 958 959 if (hook == &ng_deadhook) { 960 return; 961 } 962 do { 963 v = hook->hk_refs; 964 } while (! atomic_cmpset_int(&hook->hk_refs, v, v - 1)); 965 966 if (v == 1) { /* we were the last */ 967 if (_NG_HOOK_NODE(hook)) /* it'll probably be ng_deadnode */ 968 _NG_NODE_UNREF((_NG_HOOK_NODE(hook))); 969 NG_FREE_HOOK(hook); 970 } 971} 972 973/* 974 * Add an unconnected hook to a node. Only used internally. 975 * Assumes node is locked. (XXX not yet true ) 976 */ 977static int 978ng_add_hook(node_p node, const char *name, hook_p *hookp) 979{ 980 hook_p hook; 981 int error = 0; 982 983 /* Check that the given name is good */ 984 if (name == NULL) { 985 TRAP_ERROR(); 986 return (EINVAL); 987 } 988 if (ng_findhook(node, name) != NULL) { 989 TRAP_ERROR(); 990 return (EEXIST); 991 } 992 993 /* Allocate the hook and link it up */ 994 NG_ALLOC_HOOK(hook); 995 if (hook == NULL) { 996 TRAP_ERROR(); 997 return (ENOMEM); 998 } 999 hook->hk_refs = 1; /* add a reference for us to return */ 1000 hook->hk_flags = HK_INVALID; 1001 hook->hk_peer = &ng_deadhook; /* start off this way */ 1002 hook->hk_node = node; 1003 NG_NODE_REF(node); /* each hook counts as a reference */ 1004 1005 /* Set hook name */ 1006 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ); 1007 1008 /* 1009 * Check if the node type code has something to say about it 1010 * If it fails, the unref of the hook will also unref the node. 1011 */ 1012 if (node->nd_type->newhook != NULL) { 1013 if ((error = (*node->nd_type->newhook)(node, hook, name))) { 1014 NG_HOOK_UNREF(hook); /* this frees the hook */ 1015 return (error); 1016 } 1017 } 1018 /* 1019 * The 'type' agrees so far, so go ahead and link it in. 1020 * We'll ask again later when we actually connect the hooks. 1021 */ 1022 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1023 node->nd_numhooks++; 1024 NG_HOOK_REF(hook); /* one for the node */ 1025 1026 if (hookp) 1027 *hookp = hook; 1028 return (0); 1029} 1030 1031/* 1032 * Find a hook 1033 * 1034 * Node types may supply their own optimized routines for finding 1035 * hooks. If none is supplied, we just do a linear search. 1036 * XXX Possibly we should add a reference to the hook? 1037 */ 1038hook_p 1039ng_findhook(node_p node, const char *name) 1040{ 1041 hook_p hook; 1042 1043 if (node->nd_type->findhook != NULL) 1044 return (*node->nd_type->findhook)(node, name); 1045 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) { 1046 if (NG_HOOK_IS_VALID(hook) 1047 && (strcmp(NG_HOOK_NAME(hook), name) == 0)) 1048 return (hook); 1049 } 1050 return (NULL); 1051} 1052 1053/* 1054 * Destroy a hook 1055 * 1056 * As hooks are always attached, this really destroys two hooks. 1057 * The one given, and the one attached to it. Disconnect the hooks 1058 * from each other first. We reconnect the peer hook to the 'dead' 1059 * hook so that it can still exist after we depart. We then 1060 * send the peer its own destroy message. This ensures that we only 1061 * interact with the peer's structures when it is locked processing that 1062 * message. We hold a reference to the peer hook so we are guaranteed that 1063 * the peer hook and node are still going to exist until 1064 * we are finished there as the hook holds a ref on the node. 1065 * We run this same code again on the peer hook, but that time it is already 1066 * attached to the 'dead' hook. 1067 * 1068 * This routine is called at all stages of hook creation 1069 * on error detection and must be able to handle any such stage. 1070 */ 1071void 1072ng_destroy_hook(hook_p hook) 1073{ 1074 hook_p peer; 1075 node_p node; 1076 1077 if (hook == &ng_deadhook) { /* better safe than sorry */ 1078 printf("ng_destroy_hook called on deadhook\n"); 1079 return; 1080 } 1081 1082 /* 1083 * Protect divorce process with mutex, to avoid races on 1084 * simultaneous disconnect. 1085 */ 1086 mtx_lock(&ng_topo_mtx); 1087 1088 hook->hk_flags |= HK_INVALID; 1089 1090 peer = NG_HOOK_PEER(hook); 1091 node = NG_HOOK_NODE(hook); 1092 1093 if (peer && (peer != &ng_deadhook)) { 1094 /* 1095 * Set the peer to point to ng_deadhook 1096 * from this moment on we are effectively independent it. 1097 * send it an rmhook message of it's own. 1098 */ 1099 peer->hk_peer = &ng_deadhook; /* They no longer know us */ 1100 hook->hk_peer = &ng_deadhook; /* Nor us, them */ 1101 if (NG_HOOK_NODE(peer) == &ng_deadnode) { 1102 /* 1103 * If it's already divorced from a node, 1104 * just free it. 1105 */ 1106 mtx_unlock(&ng_topo_mtx); 1107 } else { 1108 mtx_unlock(&ng_topo_mtx); 1109 ng_rmhook_self(peer); /* Send it a surprise */ 1110 } 1111 NG_HOOK_UNREF(peer); /* account for peer link */ 1112 NG_HOOK_UNREF(hook); /* account for peer link */ 1113 } else 1114 mtx_unlock(&ng_topo_mtx); 1115 1116 mtx_assert(&ng_topo_mtx, MA_NOTOWNED); 1117 1118 /* 1119 * Remove the hook from the node's list to avoid possible recursion 1120 * in case the disconnection results in node shutdown. 1121 */ 1122 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */ 1123 return; 1124 } 1125 LIST_REMOVE(hook, hk_hooks); 1126 node->nd_numhooks--; 1127 if (node->nd_type->disconnect) { 1128 /* 1129 * The type handler may elect to destroy the node so don't 1130 * trust its existence after this point. (except 1131 * that we still hold a reference on it. (which we 1132 * inherrited from the hook we are destroying) 1133 */ 1134 (*node->nd_type->disconnect) (hook); 1135 } 1136 1137 /* 1138 * Note that because we will point to ng_deadnode, the original node 1139 * is not decremented automatically so we do that manually. 1140 */ 1141 _NG_HOOK_NODE(hook) = &ng_deadnode; 1142 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */ 1143 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */ 1144} 1145 1146/* 1147 * Take two hooks on a node and merge the connection so that the given node 1148 * is effectively bypassed. 1149 */ 1150int 1151ng_bypass(hook_p hook1, hook_p hook2) 1152{ 1153 if (hook1->hk_node != hook2->hk_node) { 1154 TRAP_ERROR(); 1155 return (EINVAL); 1156 } 1157 hook1->hk_peer->hk_peer = hook2->hk_peer; 1158 hook2->hk_peer->hk_peer = hook1->hk_peer; 1159 1160 hook1->hk_peer = &ng_deadhook; 1161 hook2->hk_peer = &ng_deadhook; 1162 1163 NG_HOOK_UNREF(hook1); 1164 NG_HOOK_UNREF(hook2); 1165 1166 /* XXX If we ever cache methods on hooks update them as well */ 1167 ng_destroy_hook(hook1); 1168 ng_destroy_hook(hook2); 1169 return (0); 1170} 1171 1172/* 1173 * Install a new netgraph type 1174 */ 1175int 1176ng_newtype(struct ng_type *tp) 1177{ 1178 const size_t namelen = strlen(tp->name); 1179 1180 /* Check version and type name fields */ 1181 if ((tp->version != NG_ABI_VERSION) 1182 || (namelen == 0) 1183 || (namelen >= NG_TYPESIZ)) { 1184 TRAP_ERROR(); 1185 if (tp->version != NG_ABI_VERSION) { 1186 printf("Netgraph: Node type rejected. ABI mismatch. Suggest recompile\n"); 1187 } 1188 return (EINVAL); 1189 } 1190 1191 /* Check for name collision */ 1192 if (ng_findtype(tp->name) != NULL) { 1193 TRAP_ERROR(); 1194 return (EEXIST); 1195 } 1196 1197 1198 /* Link in new type */ 1199 mtx_lock(&ng_typelist_mtx); 1200 LIST_INSERT_HEAD(&ng_typelist, tp, types); 1201 tp->refs = 1; /* first ref is linked list */ 1202 mtx_unlock(&ng_typelist_mtx); 1203 return (0); 1204} 1205 1206/* 1207 * unlink a netgraph type 1208 * If no examples exist 1209 */ 1210int 1211ng_rmtype(struct ng_type *tp) 1212{ 1213 /* Check for name collision */ 1214 if (tp->refs != 1) { 1215 TRAP_ERROR(); 1216 return (EBUSY); 1217 } 1218 1219 /* Unlink type */ 1220 mtx_lock(&ng_typelist_mtx); 1221 LIST_REMOVE(tp, types); 1222 mtx_unlock(&ng_typelist_mtx); 1223 return (0); 1224} 1225 1226/* 1227 * Look for a type of the name given 1228 */ 1229struct ng_type * 1230ng_findtype(const char *typename) 1231{ 1232 struct ng_type *type; 1233 1234 mtx_lock(&ng_typelist_mtx); 1235 LIST_FOREACH(type, &ng_typelist, types) { 1236 if (strcmp(type->name, typename) == 0) 1237 break; 1238 } 1239 mtx_unlock(&ng_typelist_mtx); 1240 return (type); 1241} 1242 1243/************************************************************************ 1244 Composite routines 1245************************************************************************/ 1246/* 1247 * Connect two nodes using the specified hooks, using queued functions. 1248 */ 1249static int 1250ng_con_part3(node_p node, item_p item, hook_p hook) 1251{ 1252 int error = 0; 1253 1254 /* 1255 * When we run, we know that the node 'node' is locked for us. 1256 * Our caller has a reference on the hook. 1257 * Our caller has a reference on the node. 1258 * (In this case our caller is ng_apply_item() ). 1259 * The peer hook has a reference on the hook. 1260 * We are all set up except for the final call to the node, and 1261 * the clearing of the INVALID flag. 1262 */ 1263 if (NG_HOOK_NODE(hook) == &ng_deadnode) { 1264 /* 1265 * The node must have been freed again since we last visited 1266 * here. ng_destry_hook() has this effect but nothing else does. 1267 * We should just release our references and 1268 * free anything we can think of. 1269 * Since we know it's been destroyed, and it's our caller 1270 * that holds the references, just return. 1271 */ 1272 ERROUT(ENOENT); 1273 } 1274 if (hook->hk_node->nd_type->connect) { 1275 if ((error = (*hook->hk_node->nd_type->connect) (hook))) { 1276 ng_destroy_hook(hook); /* also zaps peer */ 1277 printf("failed in ng_con_part3()\n"); 1278 ERROUT(error); 1279 } 1280 } 1281 /* 1282 * XXX this is wrong for SMP. Possibly we need 1283 * to separate out 'create' and 'invalid' flags. 1284 * should only set flags on hooks we have locked under our node. 1285 */ 1286 hook->hk_flags &= ~HK_INVALID; 1287done: 1288 NG_FREE_ITEM(item); 1289 return (error); 1290} 1291 1292static int 1293ng_con_part2(node_p node, item_p item, hook_p hook) 1294{ 1295 hook_p peer; 1296 int error = 0; 1297 1298 /* 1299 * When we run, we know that the node 'node' is locked for us. 1300 * Our caller has a reference on the hook. 1301 * Our caller has a reference on the node. 1302 * (In this case our caller is ng_apply_item() ). 1303 * The peer hook has a reference on the hook. 1304 * our node pointer points to the 'dead' node. 1305 * First check the hook name is unique. 1306 * Should not happen because we checked before queueing this. 1307 */ 1308 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) { 1309 TRAP_ERROR(); 1310 ng_destroy_hook(hook); /* should destroy peer too */ 1311 printf("failed in ng_con_part2()\n"); 1312 ERROUT(EEXIST); 1313 } 1314 /* 1315 * Check if the node type code has something to say about it 1316 * If it fails, the unref of the hook will also unref the attached node, 1317 * however since that node is 'ng_deadnode' this will do nothing. 1318 * The peer hook will also be destroyed. 1319 */ 1320 if (node->nd_type->newhook != NULL) { 1321 if ((error = (*node->nd_type->newhook)(node, hook, 1322 hook->hk_name))) { 1323 ng_destroy_hook(hook); /* should destroy peer too */ 1324 printf("failed in ng_con_part2()\n"); 1325 ERROUT(error); 1326 } 1327 } 1328 1329 /* 1330 * The 'type' agrees so far, so go ahead and link it in. 1331 * We'll ask again later when we actually connect the hooks. 1332 */ 1333 hook->hk_node = node; /* just overwrite ng_deadnode */ 1334 NG_NODE_REF(node); /* each hook counts as a reference */ 1335 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1336 node->nd_numhooks++; 1337 NG_HOOK_REF(hook); /* one for the node */ 1338 1339 /* 1340 * We now have a symmetrical situation, where both hooks have been 1341 * linked to their nodes, the newhook methods have been called 1342 * And the references are all correct. The hooks are still marked 1343 * as invalid, as we have not called the 'connect' methods 1344 * yet. 1345 * We can call the local one immediately as we have the 1346 * node locked, but we need to queue the remote one. 1347 */ 1348 if (hook->hk_node->nd_type->connect) { 1349 if ((error = (*hook->hk_node->nd_type->connect) (hook))) { 1350 ng_destroy_hook(hook); /* also zaps peer */ 1351 printf("failed in ng_con_part2(A)\n"); 1352 ERROUT(error); 1353 } 1354 } 1355 1356 /* 1357 * Acquire topo mutex to avoid race with ng_destroy_hook(). 1358 */ 1359 mtx_lock(&ng_topo_mtx); 1360 peer = hook->hk_peer; 1361 if (peer == &ng_deadhook) { 1362 mtx_unlock(&ng_topo_mtx); 1363 printf("failed in ng_con_part2(B)\n"); 1364 ng_destroy_hook(hook); 1365 ERROUT(ENOENT); 1366 } 1367 mtx_unlock(&ng_topo_mtx); 1368 1369 if ((error = ng_send_fn2(peer->hk_node, peer, item, &ng_con_part3, 1370 NULL, 0, NG_REUSE_ITEM))) { 1371 printf("failed in ng_con_part2(C)\n"); 1372 ng_destroy_hook(hook); /* also zaps peer */ 1373 return (error); /* item was consumed. */ 1374 } 1375 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */ 1376 return (0); /* item was consumed. */ 1377done: 1378 NG_FREE_ITEM(item); 1379 return (error); 1380} 1381 1382/* 1383 * Connect this node with another node. We assume that this node is 1384 * currently locked, as we are only called from an NGM_CONNECT message. 1385 */ 1386static int 1387ng_con_nodes(item_p item, node_p node, const char *name, 1388 node_p node2, const char *name2) 1389{ 1390 int error; 1391 hook_p hook; 1392 hook_p hook2; 1393 1394 if (ng_findhook(node2, name2) != NULL) { 1395 return(EEXIST); 1396 } 1397 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */ 1398 return (error); 1399 /* Allocate the other hook and link it up */ 1400 NG_ALLOC_HOOK(hook2); 1401 if (hook2 == NULL) { 1402 TRAP_ERROR(); 1403 ng_destroy_hook(hook); /* XXX check ref counts so far */ 1404 NG_HOOK_UNREF(hook); /* including our ref */ 1405 return (ENOMEM); 1406 } 1407 hook2->hk_refs = 1; /* start with a reference for us. */ 1408 hook2->hk_flags = HK_INVALID; 1409 hook2->hk_peer = hook; /* Link the two together */ 1410 hook->hk_peer = hook2; 1411 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/ 1412 NG_HOOK_REF(hook2); 1413 hook2->hk_node = &ng_deadnode; 1414 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ); 1415 1416 /* 1417 * Queue the function above. 1418 * Procesing continues in that function in the lock context of 1419 * the other node. 1420 */ 1421 if ((error = ng_send_fn2(node2, hook2, item, &ng_con_part2, NULL, 0, 1422 NG_NOFLAGS))) { 1423 printf("failed in ng_con_nodes(): %d\n", error); 1424 ng_destroy_hook(hook); /* also zaps peer */ 1425 } 1426 1427 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */ 1428 NG_HOOK_UNREF(hook2); 1429 return (error); 1430} 1431 1432/* 1433 * Make a peer and connect. 1434 * We assume that the local node is locked. 1435 * The new node probably doesn't need a lock until 1436 * it has a hook, because it cannot really have any work until then, 1437 * but we should think about it a bit more. 1438 * 1439 * The problem may come if the other node also fires up 1440 * some hardware or a timer or some other source of activation, 1441 * also it may already get a command msg via it's ID. 1442 * 1443 * We could use the same method as ng_con_nodes() but we'd have 1444 * to add ability to remove the node when failing. (Not hard, just 1445 * make arg1 point to the node to remove). 1446 * Unless of course we just ignore failure to connect and leave 1447 * an unconnected node? 1448 */ 1449static int 1450ng_mkpeer(node_p node, const char *name, const char *name2, char *type) 1451{ 1452 node_p node2; 1453 hook_p hook1, hook2; 1454 int error; 1455 1456 if ((error = ng_make_node(type, &node2))) { 1457 return (error); 1458 } 1459 1460 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */ 1461 ng_rmnode(node2, NULL, NULL, 0); 1462 return (error); 1463 } 1464 1465 if ((error = ng_add_hook(node2, name2, &hook2))) { 1466 ng_rmnode(node2, NULL, NULL, 0); 1467 ng_destroy_hook(hook1); 1468 NG_HOOK_UNREF(hook1); 1469 return (error); 1470 } 1471 1472 /* 1473 * Actually link the two hooks together. 1474 */ 1475 hook1->hk_peer = hook2; 1476 hook2->hk_peer = hook1; 1477 1478 /* Each hook is referenced by the other */ 1479 NG_HOOK_REF(hook1); 1480 NG_HOOK_REF(hook2); 1481 1482 /* Give each node the opportunity to veto the pending connection */ 1483 if (hook1->hk_node->nd_type->connect) { 1484 error = (*hook1->hk_node->nd_type->connect) (hook1); 1485 } 1486 1487 if ((error == 0) && hook2->hk_node->nd_type->connect) { 1488 error = (*hook2->hk_node->nd_type->connect) (hook2); 1489 1490 } 1491 1492 /* 1493 * drop the references we were holding on the two hooks. 1494 */ 1495 if (error) { 1496 ng_destroy_hook(hook2); /* also zaps hook1 */ 1497 ng_rmnode(node2, NULL, NULL, 0); 1498 } else { 1499 /* As a last act, allow the hooks to be used */ 1500 hook1->hk_flags &= ~HK_INVALID; 1501 hook2->hk_flags &= ~HK_INVALID; 1502 } 1503 NG_HOOK_UNREF(hook1); 1504 NG_HOOK_UNREF(hook2); 1505 return (error); 1506} 1507 1508/************************************************************************ 1509 Utility routines to send self messages 1510************************************************************************/ 1511 1512/* Shut this node down as soon as everyone is clear of it */ 1513/* Should add arg "immediately" to jump the queue */ 1514int 1515ng_rmnode_self(node_p node) 1516{ 1517 int error; 1518 1519 if (node == &ng_deadnode) 1520 return (0); 1521 node->nd_flags |= NGF_INVALID; 1522 if (node->nd_flags & NGF_CLOSING) 1523 return (0); 1524 1525 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0); 1526 return (error); 1527} 1528 1529static void 1530ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2) 1531{ 1532 ng_destroy_hook(hook); 1533 return ; 1534} 1535 1536int 1537ng_rmhook_self(hook_p hook) 1538{ 1539 int error; 1540 node_p node = NG_HOOK_NODE(hook); 1541 1542 if (node == &ng_deadnode) 1543 return (0); 1544 1545 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0); 1546 return (error); 1547} 1548 1549/*********************************************************************** 1550 * Parse and verify a string of the form: <NODE:><PATH> 1551 * 1552 * Such a string can refer to a specific node or a specific hook 1553 * on a specific node, depending on how you look at it. In the 1554 * latter case, the PATH component must not end in a dot. 1555 * 1556 * Both <NODE:> and <PATH> are optional. The <PATH> is a string 1557 * of hook names separated by dots. This breaks out the original 1558 * string, setting *nodep to "NODE" (or NULL if none) and *pathp 1559 * to "PATH" (or NULL if degenerate). Also, *hookp will point to 1560 * the final hook component of <PATH>, if any, otherwise NULL. 1561 * 1562 * This returns -1 if the path is malformed. The char ** are optional. 1563 ***********************************************************************/ 1564int 1565ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp) 1566{ 1567 char *node, *path, *hook; 1568 int k; 1569 1570 /* 1571 * Extract absolute NODE, if any 1572 */ 1573 for (path = addr; *path && *path != ':'; path++); 1574 if (*path) { 1575 node = addr; /* Here's the NODE */ 1576 *path++ = '\0'; /* Here's the PATH */ 1577 1578 /* Node name must not be empty */ 1579 if (!*node) 1580 return -1; 1581 1582 /* A name of "." is OK; otherwise '.' not allowed */ 1583 if (strcmp(node, ".") != 0) { 1584 for (k = 0; node[k]; k++) 1585 if (node[k] == '.') 1586 return -1; 1587 } 1588 } else { 1589 node = NULL; /* No absolute NODE */ 1590 path = addr; /* Here's the PATH */ 1591 } 1592 1593 /* Snoop for illegal characters in PATH */ 1594 for (k = 0; path[k]; k++) 1595 if (path[k] == ':') 1596 return -1; 1597 1598 /* Check for no repeated dots in PATH */ 1599 for (k = 0; path[k]; k++) 1600 if (path[k] == '.' && path[k + 1] == '.') 1601 return -1; 1602 1603 /* Remove extra (degenerate) dots from beginning or end of PATH */ 1604 if (path[0] == '.') 1605 path++; 1606 if (*path && path[strlen(path) - 1] == '.') 1607 path[strlen(path) - 1] = 0; 1608 1609 /* If PATH has a dot, then we're not talking about a hook */ 1610 if (*path) { 1611 for (hook = path, k = 0; path[k]; k++) 1612 if (path[k] == '.') { 1613 hook = NULL; 1614 break; 1615 } 1616 } else 1617 path = hook = NULL; 1618 1619 /* Done */ 1620 if (nodep) 1621 *nodep = node; 1622 if (pathp) 1623 *pathp = path; 1624 if (hookp) 1625 *hookp = hook; 1626 return (0); 1627} 1628 1629/* 1630 * Given a path, which may be absolute or relative, and a starting node, 1631 * return the destination node. 1632 */ 1633int 1634ng_path2noderef(node_p here, const char *address, 1635 node_p *destp, hook_p *lasthook) 1636{ 1637 char fullpath[NG_PATHSIZ]; 1638 char *nodename, *path, pbuf[2]; 1639 node_p node, oldnode; 1640 char *cp; 1641 hook_p hook = NULL; 1642 1643 /* Initialize */ 1644 if (destp == NULL) { 1645 TRAP_ERROR(); 1646 return EINVAL; 1647 } 1648 *destp = NULL; 1649 1650 /* Make a writable copy of address for ng_path_parse() */ 1651 strncpy(fullpath, address, sizeof(fullpath) - 1); 1652 fullpath[sizeof(fullpath) - 1] = '\0'; 1653 1654 /* Parse out node and sequence of hooks */ 1655 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) { 1656 TRAP_ERROR(); 1657 return EINVAL; 1658 } 1659 if (path == NULL) { 1660 pbuf[0] = '.'; /* Needs to be writable */ 1661 pbuf[1] = '\0'; 1662 path = pbuf; 1663 } 1664 1665 /* 1666 * For an absolute address, jump to the starting node. 1667 * Note that this holds a reference on the node for us. 1668 * Don't forget to drop the reference if we don't need it. 1669 */ 1670 if (nodename) { 1671 node = ng_name2noderef(here, nodename); 1672 if (node == NULL) { 1673 TRAP_ERROR(); 1674 return (ENOENT); 1675 } 1676 } else { 1677 if (here == NULL) { 1678 TRAP_ERROR(); 1679 return (EINVAL); 1680 } 1681 node = here; 1682 NG_NODE_REF(node); 1683 } 1684 1685 /* 1686 * Now follow the sequence of hooks 1687 * XXX 1688 * We actually cannot guarantee that the sequence 1689 * is not being demolished as we crawl along it 1690 * without extra-ordinary locking etc. 1691 * So this is a bit dodgy to say the least. 1692 * We can probably hold up some things by holding 1693 * the nodelist mutex for the time of this 1694 * crawl if we wanted.. At least that way we wouldn't have to 1695 * worry about the nodes disappearing, but the hooks would still 1696 * be a problem. 1697 */ 1698 for (cp = path; node != NULL && *cp != '\0'; ) { 1699 char *segment; 1700 1701 /* 1702 * Break out the next path segment. Replace the dot we just 1703 * found with a NUL; "cp" points to the next segment (or the 1704 * NUL at the end). 1705 */ 1706 for (segment = cp; *cp != '\0'; cp++) { 1707 if (*cp == '.') { 1708 *cp++ = '\0'; 1709 break; 1710 } 1711 } 1712 1713 /* Empty segment */ 1714 if (*segment == '\0') 1715 continue; 1716 1717 /* We have a segment, so look for a hook by that name */ 1718 hook = ng_findhook(node, segment); 1719 1720 /* Can't get there from here... */ 1721 if (hook == NULL 1722 || NG_HOOK_PEER(hook) == NULL 1723 || NG_HOOK_NOT_VALID(hook) 1724 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) { 1725 TRAP_ERROR(); 1726 NG_NODE_UNREF(node); 1727#if 0 1728 printf("hooknotvalid %s %s %d %d %d %d ", 1729 path, 1730 segment, 1731 hook == NULL, 1732 NG_HOOK_PEER(hook) == NULL, 1733 NG_HOOK_NOT_VALID(hook), 1734 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))); 1735#endif 1736 return (ENOENT); 1737 } 1738 1739 /* 1740 * Hop on over to the next node 1741 * XXX 1742 * Big race conditions here as hooks and nodes go away 1743 * *** Idea.. store an ng_ID_t in each hook and use that 1744 * instead of the direct hook in this crawl? 1745 */ 1746 oldnode = node; 1747 if ((node = NG_PEER_NODE(hook))) 1748 NG_NODE_REF(node); /* XXX RACE */ 1749 NG_NODE_UNREF(oldnode); /* XXX another race */ 1750 if (NG_NODE_NOT_VALID(node)) { 1751 NG_NODE_UNREF(node); /* XXX more races */ 1752 node = NULL; 1753 } 1754 } 1755 1756 /* If node somehow missing, fail here (probably this is not needed) */ 1757 if (node == NULL) { 1758 TRAP_ERROR(); 1759 return (ENXIO); 1760 } 1761 1762 /* Done */ 1763 *destp = node; 1764 if (lasthook != NULL) 1765 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL); 1766 return (0); 1767} 1768 1769/***************************************************************\ 1770* Input queue handling. 1771* All activities are submitted to the node via the input queue 1772* which implements a multiple-reader/single-writer gate. 1773* Items which cannot be handled immediately are queued. 1774* 1775* read-write queue locking inline functions * 1776\***************************************************************/ 1777 1778static __inline item_p ng_dequeue(struct ng_queue * ngq, int *rw); 1779static __inline item_p ng_acquire_read(struct ng_queue * ngq, 1780 item_p item); 1781static __inline item_p ng_acquire_write(struct ng_queue * ngq, 1782 item_p item); 1783static __inline void ng_leave_read(struct ng_queue * ngq); 1784static __inline void ng_leave_write(struct ng_queue * ngq); 1785static __inline void ng_queue_rw(struct ng_queue * ngq, 1786 item_p item, int rw); 1787 1788/* 1789 * Definition of the bits fields in the ng_queue flag word. 1790 * Defined here rather than in netgraph.h because no-one should fiddle 1791 * with them. 1792 * 1793 * The ordering here may be important! don't shuffle these. 1794 */ 1795/*- 1796 Safety Barrier--------+ (adjustable to suit taste) (not used yet) 1797 | 1798 V 1799+-------+-------+-------+-------+-------+-------+-------+-------+ 1800 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1801 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |P|A| 1802 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |O|W| 1803+-------+-------+-------+-------+-------+-------+-------+-------+ 1804 \___________________________ ____________________________/ | | 1805 V | | 1806 [active reader count] | | 1807 | | 1808 Operation Pending -------------------------------+ | 1809 | 1810 Active Writer ---------------------------------------+ 1811 1812 1813*/ 1814#define WRITER_ACTIVE 0x00000001 1815#define OP_PENDING 0x00000002 1816#define READER_INCREMENT 0x00000004 1817#define READER_MASK 0xfffffffc /* Not valid if WRITER_ACTIVE is set */ 1818#define SAFETY_BARRIER 0x00100000 /* 128K items queued should be enough */ 1819 1820/* Defines of more elaborate states on the queue */ 1821/* Mask of bits a new read cares about */ 1822#define NGQ_RMASK (WRITER_ACTIVE|OP_PENDING) 1823 1824/* Mask of bits a new write cares about */ 1825#define NGQ_WMASK (NGQ_RMASK|READER_MASK) 1826 1827/* Test to decide if there is something on the queue. */ 1828#define QUEUE_ACTIVE(QP) ((QP)->q_flags & OP_PENDING) 1829 1830/* How to decide what the next queued item is. */ 1831#define HEAD_IS_READER(QP) NGI_QUEUED_READER((QP)->queue) 1832#define HEAD_IS_WRITER(QP) NGI_QUEUED_WRITER((QP)->queue) /* notused */ 1833 1834/* Read the status to decide if the next item on the queue can now run. */ 1835#define QUEUED_READER_CAN_PROCEED(QP) \ 1836 (((QP)->q_flags & (NGQ_RMASK & ~OP_PENDING)) == 0) 1837#define QUEUED_WRITER_CAN_PROCEED(QP) \ 1838 (((QP)->q_flags & (NGQ_WMASK & ~OP_PENDING)) == 0) 1839 1840/* Is there a chance of getting ANY work off the queue? */ 1841#define NEXT_QUEUED_ITEM_CAN_PROCEED(QP) \ 1842 (QUEUE_ACTIVE(QP) && \ 1843 ((HEAD_IS_READER(QP)) ? QUEUED_READER_CAN_PROCEED(QP) : \ 1844 QUEUED_WRITER_CAN_PROCEED(QP))) 1845 1846 1847#define NGQRW_R 0 1848#define NGQRW_W 1 1849 1850/* 1851 * Taking into account the current state of the queue and node, possibly take 1852 * the next entry off the queue and return it. Return NULL if there was 1853 * nothing we could return, either because there really was nothing there, or 1854 * because the node was in a state where it cannot yet process the next item 1855 * on the queue. 1856 * 1857 * This MUST MUST MUST be called with the mutex held. 1858 */ 1859static __inline item_p 1860ng_dequeue(struct ng_queue *ngq, int *rw) 1861{ 1862 item_p item; 1863 u_int add_arg; 1864 1865 mtx_assert(&ngq->q_mtx, MA_OWNED); 1866 /* 1867 * If there is nothing queued, then just return. 1868 * No point in continuing. 1869 * XXXGL: assert this? 1870 */ 1871 if (!QUEUE_ACTIVE(ngq)) { 1872 CTR4(KTR_NET, "%20s: node [%x] (%p) queue empty; " 1873 "queue flags 0x%lx", __func__, 1874 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1875 return (NULL); 1876 } 1877 1878 /* 1879 * From here, we can assume there is a head item. 1880 * We need to find out what it is and if it can be dequeued, given 1881 * the current state of the node. 1882 */ 1883 if (HEAD_IS_READER(ngq)) { 1884 if (!QUEUED_READER_CAN_PROCEED(ngq)) { 1885 /* 1886 * It's a reader but we can't use it. 1887 * We are stalled so make sure we don't 1888 * get called again until something changes. 1889 */ 1890 ng_worklist_remove(ngq->q_node); 1891 CTR4(KTR_NET, "%20s: node [%x] (%p) queued reader " 1892 "can't proceed; queue flags 0x%lx", __func__, 1893 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1894 return (NULL); 1895 } 1896 /* 1897 * Head of queue is a reader and we have no write active. 1898 * We don't care how many readers are already active. 1899 * Add the correct increment for the reader count. 1900 */ 1901 add_arg = READER_INCREMENT; 1902 *rw = NGQRW_R; 1903 } else if (QUEUED_WRITER_CAN_PROCEED(ngq)) { 1904 /* 1905 * There is a pending write, no readers and no active writer. 1906 * This means we can go ahead with the pending writer. Note 1907 * the fact that we now have a writer, ready for when we take 1908 * it off the queue. 1909 * 1910 * We don't need to worry about a possible collision with the 1911 * fasttrack reader. 1912 * 1913 * The fasttrack thread may take a long time to discover that we 1914 * are running so we would have an inconsistent state in the 1915 * flags for a while. Since we ignore the reader count 1916 * entirely when the WRITER_ACTIVE flag is set, this should 1917 * not matter (in fact it is defined that way). If it tests 1918 * the flag before this operation, the OP_PENDING flag 1919 * will make it fail, and if it tests it later, the 1920 * WRITER_ACTIVE flag will do the same. If it is SO slow that 1921 * we have actually completed the operation, and neither flag 1922 * is set by the time that it tests the flags, then it is 1923 * actually ok for it to continue. If it completes and we've 1924 * finished and the read pending is set it still fails. 1925 * 1926 * So we can just ignore it, as long as we can ensure that the 1927 * transition from WRITE_PENDING state to the WRITER_ACTIVE 1928 * state is atomic. 1929 * 1930 * After failing, first it will be held back by the mutex, then 1931 * when it can proceed, it will queue its request, then it 1932 * would arrive at this function. Usually it will have to 1933 * leave empty handed because the ACTIVE WRITER bit will be 1934 * set. 1935 * 1936 * Adjust the flags for the new active writer. 1937 */ 1938 add_arg = WRITER_ACTIVE; 1939 *rw = NGQRW_W; 1940 /* 1941 * We want to write "active writer, no readers " Now go make 1942 * it true. In fact there may be a number in the readers 1943 * count but we know it is not true and will be fixed soon. 1944 * We will fix the flags for the next pending entry in a 1945 * moment. 1946 */ 1947 } else { 1948 /* 1949 * We can't dequeue anything.. return and say so. Probably we 1950 * have a write pending and the readers count is non zero. If 1951 * we got here because a reader hit us just at the wrong 1952 * moment with the fasttrack code, and put us in a strange 1953 * state, then it will be coming through in just a moment, 1954 * (just as soon as we release the mutex) and keep things 1955 * moving. 1956 * Make sure we remove ourselves from the work queue. It 1957 * would be a waste of effort to do all this again. 1958 */ 1959 ng_worklist_remove(ngq->q_node); 1960 CTR4(KTR_NET, "%20s: node [%x] (%p) can't dequeue anything; " 1961 "queue flags 0x%lx", __func__, 1962 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1963 return (NULL); 1964 } 1965 1966 /* 1967 * Now we dequeue the request (whatever it may be) and correct the 1968 * pending flags and the next and last pointers. 1969 */ 1970 item = ngq->queue; 1971 ngq->queue = item->el_next; 1972 CTR6(KTR_NET, "%20s: node [%x] (%p) dequeued item %p with flags 0x%lx; " 1973 "queue flags 0x%lx", __func__, 1974 ngq->q_node->nd_ID,ngq->q_node, item, item->el_flags, ngq->q_flags); 1975 if (ngq->last == &(item->el_next)) { 1976 /* 1977 * that was the last entry in the queue so set the 'last 1978 * pointer up correctly and make sure the pending flag is 1979 * clear. 1980 */ 1981 add_arg += -OP_PENDING; 1982 ngq->last = &(ngq->queue); 1983 /* 1984 * Whatever flag was set will be cleared and 1985 * the new acive field will be set by the add as well, 1986 * so we don't need to change add_arg. 1987 * But we know we don't need to be on the work list. 1988 */ 1989 atomic_add_long(&ngq->q_flags, add_arg); 1990 ng_worklist_remove(ngq->q_node); 1991 } else { 1992 /* 1993 * Since there is still something on the queue 1994 * we don't need to change the PENDING flag. 1995 */ 1996 atomic_add_long(&ngq->q_flags, add_arg); 1997 } 1998 CTR6(KTR_NET, "%20s: node [%x] (%p) returning item %p as %s; " 1999 "queue flags 0x%lx", __func__, 2000 ngq->q_node->nd_ID, ngq->q_node, item, *rw ? "WRITER" : "READER" , 2001 ngq->q_flags); 2002 return (item); 2003} 2004 2005/* 2006 * Queue a packet to be picked up by someone else. 2007 * We really don't care who, but we can't or don't want to hang around 2008 * to process it ourselves. We are probably an interrupt routine.. 2009 * If the queue could be run, flag the netisr handler to start. 2010 */ 2011static __inline void 2012ng_queue_rw(struct ng_queue * ngq, item_p item, int rw) 2013{ 2014 mtx_assert(&ngq->q_mtx, MA_OWNED); 2015 2016 if (rw == NGQRW_W) 2017 NGI_SET_WRITER(item); 2018 else 2019 NGI_SET_READER(item); 2020 item->el_next = NULL; /* maybe not needed */ 2021 *ngq->last = item; 2022 CTR5(KTR_NET, "%20s: node [%x] (%p) queued item %p as %s", __func__, 2023 ngq->q_node->nd_ID, ngq->q_node, item, rw ? "WRITER" : "READER" ); 2024 /* 2025 * If it was the first item in the queue then we need to 2026 * set the last pointer and the type flags. 2027 */ 2028 if (ngq->last == &(ngq->queue)) { 2029 atomic_add_long(&ngq->q_flags, OP_PENDING); 2030 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__, 2031 ngq->q_node->nd_ID, ngq->q_node); 2032 } 2033 2034 ngq->last = &(item->el_next); 2035 /* 2036 * We can take the worklist lock with the node locked 2037 * BUT NOT THE REVERSE! 2038 */ 2039 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2040 ng_setisr(ngq->q_node); 2041} 2042 2043 2044/* 2045 * This function 'cheats' in that it first tries to 'grab' the use of the 2046 * node, without going through the mutex. We can do this becasue of the 2047 * semantics of the lock. The semantics include a clause that says that the 2048 * value of the readers count is invalid if the WRITER_ACTIVE flag is set. It 2049 * also says that the WRITER_ACTIVE flag cannot be set if the readers count 2050 * is not zero. Note that this talks about what is valid to SET the 2051 * WRITER_ACTIVE flag, because from the moment it is set, the value if the 2052 * reader count is immaterial, and not valid. The two 'pending' flags have a 2053 * similar effect, in that If they are orthogonal to the two active fields in 2054 * how they are set, but if either is set, the attempted 'grab' need to be 2055 * backed out because there is earlier work, and we maintain ordering in the 2056 * queue. The result of this is that the reader request can try obtain use of 2057 * the node with only a single atomic addition, and without any of the mutex 2058 * overhead. If this fails the operation degenerates to the same as for other 2059 * cases. 2060 * 2061 */ 2062static __inline item_p 2063ng_acquire_read(struct ng_queue *ngq, item_p item) 2064{ 2065 KASSERT(ngq != &ng_deadnode.nd_input_queue, 2066 ("%s: working on deadnode", __func__)); 2067 2068 /* ######### Hack alert ######### */ 2069 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 2070 if ((ngq->q_flags & NGQ_RMASK) == 0) { 2071 /* Successfully grabbed node */ 2072 CTR4(KTR_NET, "%20s: node [%x] (%p) fast acquired item %p", 2073 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2074 return (item); 2075 } 2076 /* undo the damage if we didn't succeed */ 2077 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 2078 2079 /* ######### End Hack alert ######### */ 2080 NG_QUEUE_LOCK(ngq); 2081 /* 2082 * Try again. Another processor (or interrupt for that matter) may 2083 * have removed the last queued item that was stopping us from 2084 * running, between the previous test, and the moment that we took 2085 * the mutex. (Or maybe a writer completed.) 2086 * Even if another fast-track reader hits during this period 2087 * we don't care as multiple readers is OK. 2088 */ 2089 if ((ngq->q_flags & NGQ_RMASK) == 0) { 2090 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 2091 NG_QUEUE_UNLOCK(ngq); 2092 CTR4(KTR_NET, "%20s: node [%x] (%p) slow acquired item %p", 2093 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2094 return (item); 2095 } 2096 2097 /* 2098 * and queue the request for later. 2099 */ 2100 ng_queue_rw(ngq, item, NGQRW_R); 2101 NG_QUEUE_UNLOCK(ngq); 2102 2103 return (NULL); 2104} 2105 2106static __inline item_p 2107ng_acquire_write(struct ng_queue *ngq, item_p item) 2108{ 2109 KASSERT(ngq != &ng_deadnode.nd_input_queue, 2110 ("%s: working on deadnode", __func__)); 2111 2112restart: 2113 NG_QUEUE_LOCK(ngq); 2114 /* 2115 * If there are no readers, no writer, and no pending packets, then 2116 * we can just go ahead. In all other situations we need to queue the 2117 * request 2118 */ 2119 if ((ngq->q_flags & NGQ_WMASK) == 0) { 2120 /* collision could happen *HERE* */ 2121 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE); 2122 NG_QUEUE_UNLOCK(ngq); 2123 if (ngq->q_flags & READER_MASK) { 2124 /* Collision with fast-track reader */ 2125 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2126 goto restart; 2127 } 2128 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p", 2129 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2130 return (item); 2131 } 2132 2133 /* 2134 * and queue the request for later. 2135 */ 2136 ng_queue_rw(ngq, item, NGQRW_W); 2137 NG_QUEUE_UNLOCK(ngq); 2138 2139 return (NULL); 2140} 2141 2142#if 0 2143static __inline item_p 2144ng_upgrade_write(struct ng_queue *ngq, item_p item) 2145{ 2146 KASSERT(ngq != &ng_deadnode.nd_input_queue, 2147 ("%s: working on deadnode", __func__)); 2148 2149 NGI_SET_WRITER(item); 2150 2151 mtx_lock_spin(&(ngq->q_mtx)); 2152 2153 /* 2154 * There will never be no readers as we are there ourselves. 2155 * Set the WRITER_ACTIVE flags ASAP to block out fast track readers. 2156 * The caller we are running from will call ng_leave_read() 2157 * soon, so we must account for that. We must leave again with the 2158 * READER lock. If we find other readers, then 2159 * queue the request for later. However "later" may be rignt now 2160 * if there are no readers. We don't really care if there are queued 2161 * items as we will bypass them anyhow. 2162 */ 2163 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE - READER_INCREMENT); 2164 if (ngq->q_flags & (NGQ_WMASK & ~OP_PENDING) == WRITER_ACTIVE) { 2165 mtx_unlock_spin(&(ngq->q_mtx)); 2166 2167 /* It's just us, act on the item. */ 2168 /* will NOT drop writer lock when done */ 2169 ng_apply_item(node, item, 0); 2170 2171 /* 2172 * Having acted on the item, atomically 2173 * down grade back to READER and finish up 2174 */ 2175 atomic_add_long(&ngq->q_flags, 2176 READER_INCREMENT - WRITER_ACTIVE); 2177 2178 /* Our caller will call ng_leave_read() */ 2179 return; 2180 } 2181 /* 2182 * It's not just us active, so queue us AT THE HEAD. 2183 * "Why?" I hear you ask. 2184 * Put us at the head of the queue as we've already been 2185 * through it once. If there is nothing else waiting, 2186 * set the correct flags. 2187 */ 2188 if ((item->el_next = ngq->queue) == NULL) { 2189 /* 2190 * Set up the "last" pointer. 2191 * We are the only (and thus last) item 2192 */ 2193 ngq->last = &(item->el_next); 2194 2195 /* We've gone from, 0 to 1 item in the queue */ 2196 atomic_add_long(&ngq->q_flags, OP_PENDING); 2197 2198 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__, 2199 ngq->q_node->nd_ID, ngq->q_node); 2200 }; 2201 ngq->queue = item; 2202 CTR5(KTR_NET, "%20s: node [%x] (%p) requeued item %p as WRITER", 2203 __func__, ngq->q_node->nd_ID, ngq->q_node, item ); 2204 2205 /* Reverse what we did above. That downgrades us back to reader */ 2206 atomic_add_long(&ngq->q_flags, READER_INCREMENT - WRITER_ACTIVE); 2207 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2208 ng_setisr(ngq->q_node); 2209 mtx_unlock_spin(&(ngq->q_mtx)); 2210 2211 return; 2212} 2213 2214#endif 2215 2216static __inline void 2217ng_leave_read(struct ng_queue *ngq) 2218{ 2219 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 2220} 2221 2222static __inline void 2223ng_leave_write(struct ng_queue *ngq) 2224{ 2225 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2226} 2227 2228static void 2229ng_flush_input_queue(struct ng_queue * ngq) 2230{ 2231 item_p item; 2232 2233 NG_QUEUE_LOCK(ngq); 2234 while (ngq->queue) { 2235 item = ngq->queue; 2236 ngq->queue = item->el_next; 2237 if (ngq->last == &(item->el_next)) { 2238 ngq->last = &(ngq->queue); 2239 atomic_add_long(&ngq->q_flags, -OP_PENDING); 2240 } 2241 NG_QUEUE_UNLOCK(ngq); 2242 2243 /* If the item is supplying a callback, call it with an error */ 2244 if (item->apply != NULL) { 2245 if (item->depth == 1) 2246 item->apply->error = ENOENT; 2247 if (refcount_release(&item->apply->refs)) { 2248 (*item->apply->apply)(item->apply->context, 2249 item->apply->error); 2250 } 2251 } 2252 NG_FREE_ITEM(item); 2253 NG_QUEUE_LOCK(ngq); 2254 } 2255 /* 2256 * Take us off the work queue if we are there. 2257 * We definately have no work to be done. 2258 */ 2259 ng_worklist_remove(ngq->q_node); 2260 NG_QUEUE_UNLOCK(ngq); 2261} 2262 2263/*********************************************************************** 2264* Externally visible method for sending or queueing messages or data. 2265***********************************************************************/ 2266 2267/* 2268 * The module code should have filled out the item correctly by this stage: 2269 * Common: 2270 * reference to destination node. 2271 * Reference to destination rcv hook if relevant. 2272 * apply pointer must be or NULL or reference valid struct ng_apply_info. 2273 * Data: 2274 * pointer to mbuf 2275 * Control_Message: 2276 * pointer to msg. 2277 * ID of original sender node. (return address) 2278 * Function: 2279 * Function pointer 2280 * void * argument 2281 * integer argument 2282 * 2283 * The nodes have several routines and macros to help with this task: 2284 */ 2285 2286int 2287ng_snd_item(item_p item, int flags) 2288{ 2289 hook_p hook; 2290 node_p node; 2291 int queue, rw; 2292 struct ng_queue *ngq; 2293 int error = 0; 2294 2295 /* We are sending item, so it must be present! */ 2296 KASSERT(item != NULL, ("ng_snd_item: item is NULL")); 2297 2298#ifdef NETGRAPH_DEBUG 2299 _ngi_check(item, __FILE__, __LINE__); 2300#endif 2301 2302 /* Item was sent once more, postpone apply() call. */ 2303 if (item->apply) 2304 refcount_acquire(&item->apply->refs); 2305 2306 node = NGI_NODE(item); 2307 /* Node is never optional. */ 2308 KASSERT(node != NULL, ("ng_snd_item: node is NULL")); 2309 2310 hook = NGI_HOOK(item); 2311 /* Valid hook and mbuf are mandatory for data. */ 2312 if ((item->el_flags & NGQF_TYPE) == NGQF_DATA) { 2313 KASSERT(hook != NULL, ("ng_snd_item: hook for data is NULL")); 2314 if (NGI_M(item) == NULL) 2315 ERROUT(EINVAL); 2316 CHECK_DATA_MBUF(NGI_M(item)); 2317 } 2318 2319 /* 2320 * If the item or the node specifies single threading, force 2321 * writer semantics. Similarly, the node may say one hook always 2322 * produces writers. These are overrides. 2323 */ 2324 if (((item->el_flags & NGQF_RW) == NGQF_WRITER) || 2325 (node->nd_flags & NGF_FORCE_WRITER) || 2326 (hook && (hook->hk_flags & HK_FORCE_WRITER))) { 2327 rw = NGQRW_W; 2328 } else { 2329 rw = NGQRW_R; 2330 } 2331 2332 /* 2333 * If sender or receiver requests queued delivery or stack usage 2334 * level is dangerous - enqueue message. 2335 */ 2336 if ((flags & NG_QUEUE) || (hook && (hook->hk_flags & HK_QUEUE))) { 2337 queue = 1; 2338 } else { 2339 queue = 0; 2340#ifdef GET_STACK_USAGE 2341 /* 2342 * Most of netgraph nodes have small stack consumption and 2343 * for them 25% of free stack space is more than enough. 2344 * Nodes/hooks with higher stack usage should be marked as 2345 * HI_STACK. For them 50% of stack will be guaranteed then. 2346 * XXX: Values 25% and 50% are completely empirical. 2347 */ 2348 size_t st, su, sl; 2349 GET_STACK_USAGE(st, su); 2350 sl = st - su; 2351 if ((sl * 4 < st) || 2352 ((sl * 2 < st) && ((node->nd_flags & NGF_HI_STACK) || 2353 (hook && (hook->hk_flags & HK_HI_STACK))))) { 2354 queue = 1; 2355 } 2356#endif 2357 } 2358 2359 ngq = &node->nd_input_queue; 2360 if (queue) { 2361 /* Put it on the queue for that node*/ 2362#ifdef NETGRAPH_DEBUG 2363 _ngi_check(item, __FILE__, __LINE__); 2364#endif 2365 item->depth = 1; 2366 NG_QUEUE_LOCK(ngq); 2367 ng_queue_rw(ngq, item, rw); 2368 NG_QUEUE_UNLOCK(ngq); 2369 2370 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0); 2371 } 2372 2373 /* 2374 * We already decided how we will be queueud or treated. 2375 * Try get the appropriate operating permission. 2376 */ 2377 if (rw == NGQRW_R) 2378 item = ng_acquire_read(ngq, item); 2379 else 2380 item = ng_acquire_write(ngq, item); 2381 2382 2383 /* Item was queued while trying to get permission. */ 2384 if (item == NULL) 2385 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0); 2386 2387#ifdef NETGRAPH_DEBUG 2388 _ngi_check(item, __FILE__, __LINE__); 2389#endif 2390 2391 NGI_GET_NODE(item, node); /* zaps stored node */ 2392 2393 item->depth++; 2394 error = ng_apply_item(node, item, rw); /* drops r/w lock when done */ 2395 2396 /* 2397 * If the node goes away when we remove the reference, 2398 * whatever we just did caused it.. whatever we do, DO NOT 2399 * access the node again! 2400 */ 2401 if (NG_NODE_UNREF(node) == 0) 2402 return (error); 2403 2404 NG_QUEUE_LOCK(ngq); 2405 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2406 ng_setisr(ngq->q_node); 2407 NG_QUEUE_UNLOCK(ngq); 2408 2409 return (error); 2410 2411done: 2412 /* If was not sent, apply callback here. */ 2413 if (item->apply != NULL) { 2414 if (item->depth == 0 && error != 0) 2415 item->apply->error = error; 2416 if (refcount_release(&item->apply->refs)) { 2417 (*item->apply->apply)(item->apply->context, 2418 item->apply->error); 2419 } 2420 } 2421 2422 NG_FREE_ITEM(item); 2423 return (error); 2424} 2425 2426/* 2427 * We have an item that was possibly queued somewhere. 2428 * It should contain all the information needed 2429 * to run it on the appropriate node/hook. 2430 * If there is apply pointer and we own the last reference, call apply(). 2431 */ 2432static int 2433ng_apply_item(node_p node, item_p item, int rw) 2434{ 2435 hook_p hook; 2436 ng_rcvdata_t *rcvdata; 2437 ng_rcvmsg_t *rcvmsg; 2438 struct ng_apply_info *apply; 2439 int error = 0, depth; 2440 2441 /* Node and item are never optional. */ 2442 KASSERT(node != NULL, ("ng_apply_item: node is NULL")); 2443 KASSERT(item != NULL, ("ng_apply_item: item is NULL")); 2444 2445 NGI_GET_HOOK(item, hook); /* clears stored hook */ 2446#ifdef NETGRAPH_DEBUG 2447 _ngi_check(item, __FILE__, __LINE__); 2448#endif 2449 2450 apply = item->apply; 2451 depth = item->depth; 2452 2453 switch (item->el_flags & NGQF_TYPE) { 2454 case NGQF_DATA: 2455 /* 2456 * Check things are still ok as when we were queued. 2457 */ 2458 KASSERT(hook != NULL, ("ng_apply_item: hook for data is NULL")); 2459 if (NG_HOOK_NOT_VALID(hook) || 2460 NG_NODE_NOT_VALID(node)) { 2461 error = EIO; 2462 NG_FREE_ITEM(item); 2463 break; 2464 } 2465 /* 2466 * If no receive method, just silently drop it. 2467 * Give preference to the hook over-ride method 2468 */ 2469 if ((!(rcvdata = hook->hk_rcvdata)) 2470 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) { 2471 error = 0; 2472 NG_FREE_ITEM(item); 2473 break; 2474 } 2475 error = (*rcvdata)(hook, item); 2476 break; 2477 case NGQF_MESG: 2478 if (hook && NG_HOOK_NOT_VALID(hook)) { 2479 /* 2480 * The hook has been zapped then we can't use it. 2481 * Immediately drop its reference. 2482 * The message may not need it. 2483 */ 2484 NG_HOOK_UNREF(hook); 2485 hook = NULL; 2486 } 2487 /* 2488 * Similarly, if the node is a zombie there is 2489 * nothing we can do with it, drop everything. 2490 */ 2491 if (NG_NODE_NOT_VALID(node)) { 2492 TRAP_ERROR(); 2493 error = EINVAL; 2494 NG_FREE_ITEM(item); 2495 break; 2496 } 2497 /* 2498 * Call the appropriate message handler for the object. 2499 * It is up to the message handler to free the message. 2500 * If it's a generic message, handle it generically, 2501 * otherwise call the type's message handler (if it exists). 2502 * XXX (race). Remember that a queued message may 2503 * reference a node or hook that has just been 2504 * invalidated. It will exist as the queue code 2505 * is holding a reference, but.. 2506 */ 2507 if ((NGI_MSG(item)->header.typecookie == NGM_GENERIC_COOKIE) && 2508 ((NGI_MSG(item)->header.flags & NGF_RESP) == 0)) { 2509 error = ng_generic_msg(node, item, hook); 2510 break; 2511 } 2512 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) && 2513 (!(rcvmsg = node->nd_type->rcvmsg))) { 2514 TRAP_ERROR(); 2515 error = 0; 2516 NG_FREE_ITEM(item); 2517 break; 2518 } 2519 error = (*rcvmsg)(node, item, hook); 2520 break; 2521 case NGQF_FN: 2522 case NGQF_FN2: 2523 /* 2524 * We have to implicitly trust the hook, 2525 * as some of these are used for system purposes 2526 * where the hook is invalid. In the case of 2527 * the shutdown message we allow it to hit 2528 * even if the node is invalid. 2529 */ 2530 if ((NG_NODE_NOT_VALID(node)) 2531 && (NGI_FN(item) != &ng_rmnode)) { 2532 TRAP_ERROR(); 2533 error = EINVAL; 2534 NG_FREE_ITEM(item); 2535 break; 2536 } 2537 if ((item->el_flags & NGQF_TYPE) == NGQF_FN) { 2538 (*NGI_FN(item))(node, hook, NGI_ARG1(item), 2539 NGI_ARG2(item)); 2540 NG_FREE_ITEM(item); 2541 } else /* it is NGQF_FN2 */ 2542 error = (*NGI_FN2(item))(node, item, hook); 2543 break; 2544 } 2545 /* 2546 * We held references on some of the resources 2547 * that we took from the item. Now that we have 2548 * finished doing everything, drop those references. 2549 */ 2550 if (hook) 2551 NG_HOOK_UNREF(hook); 2552 2553 if (rw == NGQRW_R) 2554 ng_leave_read(&node->nd_input_queue); 2555 else 2556 ng_leave_write(&node->nd_input_queue); 2557 2558 /* Apply callback. */ 2559 if (apply != NULL) { 2560 if (depth == 1 && error != 0) 2561 apply->error = error; 2562 if (refcount_release(&apply->refs)) 2563 (*apply->apply)(apply->context, apply->error); 2564 } 2565 2566 return (error); 2567} 2568 2569/*********************************************************************** 2570 * Implement the 'generic' control messages 2571 ***********************************************************************/ 2572static int 2573ng_generic_msg(node_p here, item_p item, hook_p lasthook) 2574{ 2575 int error = 0; 2576 struct ng_mesg *msg; 2577 struct ng_mesg *resp = NULL; 2578 2579 NGI_GET_MSG(item, msg); 2580 if (msg->header.typecookie != NGM_GENERIC_COOKIE) { 2581 TRAP_ERROR(); 2582 error = EINVAL; 2583 goto out; 2584 } 2585 switch (msg->header.cmd) { 2586 case NGM_SHUTDOWN: 2587 ng_rmnode(here, NULL, NULL, 0); 2588 break; 2589 case NGM_MKPEER: 2590 { 2591 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data; 2592 2593 if (msg->header.arglen != sizeof(*mkp)) { 2594 TRAP_ERROR(); 2595 error = EINVAL; 2596 break; 2597 } 2598 mkp->type[sizeof(mkp->type) - 1] = '\0'; 2599 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0'; 2600 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0'; 2601 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type); 2602 break; 2603 } 2604 case NGM_CONNECT: 2605 { 2606 struct ngm_connect *const con = 2607 (struct ngm_connect *) msg->data; 2608 node_p node2; 2609 2610 if (msg->header.arglen != sizeof(*con)) { 2611 TRAP_ERROR(); 2612 error = EINVAL; 2613 break; 2614 } 2615 con->path[sizeof(con->path) - 1] = '\0'; 2616 con->ourhook[sizeof(con->ourhook) - 1] = '\0'; 2617 con->peerhook[sizeof(con->peerhook) - 1] = '\0'; 2618 /* Don't forget we get a reference.. */ 2619 error = ng_path2noderef(here, con->path, &node2, NULL); 2620 if (error) 2621 break; 2622 error = ng_con_nodes(item, here, con->ourhook, 2623 node2, con->peerhook); 2624 NG_NODE_UNREF(node2); 2625 break; 2626 } 2627 case NGM_NAME: 2628 { 2629 struct ngm_name *const nam = (struct ngm_name *) msg->data; 2630 2631 if (msg->header.arglen != sizeof(*nam)) { 2632 TRAP_ERROR(); 2633 error = EINVAL; 2634 break; 2635 } 2636 nam->name[sizeof(nam->name) - 1] = '\0'; 2637 error = ng_name_node(here, nam->name); 2638 break; 2639 } 2640 case NGM_RMHOOK: 2641 { 2642 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data; 2643 hook_p hook; 2644 2645 if (msg->header.arglen != sizeof(*rmh)) { 2646 TRAP_ERROR(); 2647 error = EINVAL; 2648 break; 2649 } 2650 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0'; 2651 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL) 2652 ng_destroy_hook(hook); 2653 break; 2654 } 2655 case NGM_NODEINFO: 2656 { 2657 struct nodeinfo *ni; 2658 2659 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT); 2660 if (resp == NULL) { 2661 error = ENOMEM; 2662 break; 2663 } 2664 2665 /* Fill in node info */ 2666 ni = (struct nodeinfo *) resp->data; 2667 if (NG_NODE_HAS_NAME(here)) 2668 strcpy(ni->name, NG_NODE_NAME(here)); 2669 strcpy(ni->type, here->nd_type->name); 2670 ni->id = ng_node2ID(here); 2671 ni->hooks = here->nd_numhooks; 2672 break; 2673 } 2674 case NGM_LISTHOOKS: 2675 { 2676 const int nhooks = here->nd_numhooks; 2677 struct hooklist *hl; 2678 struct nodeinfo *ni; 2679 hook_p hook; 2680 2681 /* Get response struct */ 2682 NG_MKRESPONSE(resp, msg, sizeof(*hl) 2683 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT); 2684 if (resp == NULL) { 2685 error = ENOMEM; 2686 break; 2687 } 2688 hl = (struct hooklist *) resp->data; 2689 ni = &hl->nodeinfo; 2690 2691 /* Fill in node info */ 2692 if (NG_NODE_HAS_NAME(here)) 2693 strcpy(ni->name, NG_NODE_NAME(here)); 2694 strcpy(ni->type, here->nd_type->name); 2695 ni->id = ng_node2ID(here); 2696 2697 /* Cycle through the linked list of hooks */ 2698 ni->hooks = 0; 2699 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) { 2700 struct linkinfo *const link = &hl->link[ni->hooks]; 2701 2702 if (ni->hooks >= nhooks) { 2703 log(LOG_ERR, "%s: number of %s changed\n", 2704 __func__, "hooks"); 2705 break; 2706 } 2707 if (NG_HOOK_NOT_VALID(hook)) 2708 continue; 2709 strcpy(link->ourhook, NG_HOOK_NAME(hook)); 2710 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook)); 2711 if (NG_PEER_NODE_NAME(hook)[0] != '\0') 2712 strcpy(link->nodeinfo.name, 2713 NG_PEER_NODE_NAME(hook)); 2714 strcpy(link->nodeinfo.type, 2715 NG_PEER_NODE(hook)->nd_type->name); 2716 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook)); 2717 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks; 2718 ni->hooks++; 2719 } 2720 break; 2721 } 2722 2723 case NGM_LISTNAMES: 2724 case NGM_LISTNODES: 2725 { 2726 const int unnamed = (msg->header.cmd == NGM_LISTNODES); 2727 struct namelist *nl; 2728 node_p node; 2729 int num = 0, i; 2730 2731 mtx_lock(&ng_namehash_mtx); 2732 /* Count number of nodes */ 2733 for (i = 0; i < NG_NAME_HASH_SIZE; i++) { 2734 LIST_FOREACH(node, &ng_name_hash[i], nd_nodes) { 2735 if (NG_NODE_IS_VALID(node) && 2736 (unnamed || NG_NODE_HAS_NAME(node))) { 2737 num++; 2738 } 2739 } 2740 } 2741 mtx_unlock(&ng_namehash_mtx); 2742 2743 /* Get response struct */ 2744 NG_MKRESPONSE(resp, msg, sizeof(*nl) 2745 + (num * sizeof(struct nodeinfo)), M_NOWAIT); 2746 if (resp == NULL) { 2747 error = ENOMEM; 2748 break; 2749 } 2750 nl = (struct namelist *) resp->data; 2751 2752 /* Cycle through the linked list of nodes */ 2753 nl->numnames = 0; 2754 mtx_lock(&ng_namehash_mtx); 2755 for (i = 0; i < NG_NAME_HASH_SIZE; i++) { 2756 LIST_FOREACH(node, &ng_name_hash[i], nd_nodes) { 2757 struct nodeinfo *const np = 2758 &nl->nodeinfo[nl->numnames]; 2759 2760 if (NG_NODE_NOT_VALID(node)) 2761 continue; 2762 if (!unnamed && (! NG_NODE_HAS_NAME(node))) 2763 continue; 2764 if (nl->numnames >= num) { 2765 log(LOG_ERR, "%s: number of nodes changed\n", 2766 __func__); 2767 break; 2768 } 2769 if (NG_NODE_HAS_NAME(node)) 2770 strcpy(np->name, NG_NODE_NAME(node)); 2771 strcpy(np->type, node->nd_type->name); 2772 np->id = ng_node2ID(node); 2773 np->hooks = node->nd_numhooks; 2774 nl->numnames++; 2775 } 2776 } 2777 mtx_unlock(&ng_namehash_mtx); 2778 break; 2779 } 2780 2781 case NGM_LISTTYPES: 2782 { 2783 struct typelist *tl; 2784 struct ng_type *type; 2785 int num = 0; 2786 2787 mtx_lock(&ng_typelist_mtx); 2788 /* Count number of types */ 2789 LIST_FOREACH(type, &ng_typelist, types) { 2790 num++; 2791 } 2792 mtx_unlock(&ng_typelist_mtx); 2793 2794 /* Get response struct */ 2795 NG_MKRESPONSE(resp, msg, sizeof(*tl) 2796 + (num * sizeof(struct typeinfo)), M_NOWAIT); 2797 if (resp == NULL) { 2798 error = ENOMEM; 2799 break; 2800 } 2801 tl = (struct typelist *) resp->data; 2802 2803 /* Cycle through the linked list of types */ 2804 tl->numtypes = 0; 2805 mtx_lock(&ng_typelist_mtx); 2806 LIST_FOREACH(type, &ng_typelist, types) { 2807 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes]; 2808 2809 if (tl->numtypes >= num) { 2810 log(LOG_ERR, "%s: number of %s changed\n", 2811 __func__, "types"); 2812 break; 2813 } 2814 strcpy(tp->type_name, type->name); 2815 tp->numnodes = type->refs - 1; /* don't count list */ 2816 tl->numtypes++; 2817 } 2818 mtx_unlock(&ng_typelist_mtx); 2819 break; 2820 } 2821 2822 case NGM_BINARY2ASCII: 2823 { 2824 int bufSize = 20 * 1024; /* XXX hard coded constant */ 2825 const struct ng_parse_type *argstype; 2826 const struct ng_cmdlist *c; 2827 struct ng_mesg *binary, *ascii; 2828 2829 /* Data area must contain a valid netgraph message */ 2830 binary = (struct ng_mesg *)msg->data; 2831 if (msg->header.arglen < sizeof(struct ng_mesg) || 2832 (msg->header.arglen - sizeof(struct ng_mesg) < 2833 binary->header.arglen)) { 2834 TRAP_ERROR(); 2835 error = EINVAL; 2836 break; 2837 } 2838 2839 /* Get a response message with lots of room */ 2840 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT); 2841 if (resp == NULL) { 2842 error = ENOMEM; 2843 break; 2844 } 2845 ascii = (struct ng_mesg *)resp->data; 2846 2847 /* Copy binary message header to response message payload */ 2848 bcopy(binary, ascii, sizeof(*binary)); 2849 2850 /* Find command by matching typecookie and command number */ 2851 for (c = here->nd_type->cmdlist; 2852 c != NULL && c->name != NULL; c++) { 2853 if (binary->header.typecookie == c->cookie 2854 && binary->header.cmd == c->cmd) 2855 break; 2856 } 2857 if (c == NULL || c->name == NULL) { 2858 for (c = ng_generic_cmds; c->name != NULL; c++) { 2859 if (binary->header.typecookie == c->cookie 2860 && binary->header.cmd == c->cmd) 2861 break; 2862 } 2863 if (c->name == NULL) { 2864 NG_FREE_MSG(resp); 2865 error = ENOSYS; 2866 break; 2867 } 2868 } 2869 2870 /* Convert command name to ASCII */ 2871 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr), 2872 "%s", c->name); 2873 2874 /* Convert command arguments to ASCII */ 2875 argstype = (binary->header.flags & NGF_RESP) ? 2876 c->respType : c->mesgType; 2877 if (argstype == NULL) { 2878 *ascii->data = '\0'; 2879 } else { 2880 if ((error = ng_unparse(argstype, 2881 (u_char *)binary->data, 2882 ascii->data, bufSize)) != 0) { 2883 NG_FREE_MSG(resp); 2884 break; 2885 } 2886 } 2887 2888 /* Return the result as struct ng_mesg plus ASCII string */ 2889 bufSize = strlen(ascii->data) + 1; 2890 ascii->header.arglen = bufSize; 2891 resp->header.arglen = sizeof(*ascii) + bufSize; 2892 break; 2893 } 2894 2895 case NGM_ASCII2BINARY: 2896 { 2897 int bufSize = 2000; /* XXX hard coded constant */ 2898 const struct ng_cmdlist *c; 2899 const struct ng_parse_type *argstype; 2900 struct ng_mesg *ascii, *binary; 2901 int off = 0; 2902 2903 /* Data area must contain at least a struct ng_mesg + '\0' */ 2904 ascii = (struct ng_mesg *)msg->data; 2905 if ((msg->header.arglen < sizeof(*ascii) + 1) || 2906 (ascii->header.arglen < 1) || 2907 (msg->header.arglen < sizeof(*ascii) + 2908 ascii->header.arglen)) { 2909 TRAP_ERROR(); 2910 error = EINVAL; 2911 break; 2912 } 2913 ascii->data[ascii->header.arglen - 1] = '\0'; 2914 2915 /* Get a response message with lots of room */ 2916 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT); 2917 if (resp == NULL) { 2918 error = ENOMEM; 2919 break; 2920 } 2921 binary = (struct ng_mesg *)resp->data; 2922 2923 /* Copy ASCII message header to response message payload */ 2924 bcopy(ascii, binary, sizeof(*ascii)); 2925 2926 /* Find command by matching ASCII command string */ 2927 for (c = here->nd_type->cmdlist; 2928 c != NULL && c->name != NULL; c++) { 2929 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2930 break; 2931 } 2932 if (c == NULL || c->name == NULL) { 2933 for (c = ng_generic_cmds; c->name != NULL; c++) { 2934 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2935 break; 2936 } 2937 if (c->name == NULL) { 2938 NG_FREE_MSG(resp); 2939 error = ENOSYS; 2940 break; 2941 } 2942 } 2943 2944 /* Convert command name to binary */ 2945 binary->header.cmd = c->cmd; 2946 binary->header.typecookie = c->cookie; 2947 2948 /* Convert command arguments to binary */ 2949 argstype = (binary->header.flags & NGF_RESP) ? 2950 c->respType : c->mesgType; 2951 if (argstype == NULL) { 2952 bufSize = 0; 2953 } else { 2954 if ((error = ng_parse(argstype, ascii->data, 2955 &off, (u_char *)binary->data, &bufSize)) != 0) { 2956 NG_FREE_MSG(resp); 2957 break; 2958 } 2959 } 2960 2961 /* Return the result */ 2962 binary->header.arglen = bufSize; 2963 resp->header.arglen = sizeof(*binary) + bufSize; 2964 break; 2965 } 2966 2967 case NGM_TEXT_CONFIG: 2968 case NGM_TEXT_STATUS: 2969 /* 2970 * This one is tricky as it passes the command down to the 2971 * actual node, even though it is a generic type command. 2972 * This means we must assume that the item/msg is already freed 2973 * when control passes back to us. 2974 */ 2975 if (here->nd_type->rcvmsg != NULL) { 2976 NGI_MSG(item) = msg; /* put it back as we found it */ 2977 return((*here->nd_type->rcvmsg)(here, item, lasthook)); 2978 } 2979 /* Fall through if rcvmsg not supported */ 2980 default: 2981 TRAP_ERROR(); 2982 error = EINVAL; 2983 } 2984 /* 2985 * Sometimes a generic message may be statically allocated 2986 * to avoid problems with allocating when in tight memeory situations. 2987 * Don't free it if it is so. 2988 * I break them appart here, because erros may cause a free if the item 2989 * in which case we'd be doing it twice. 2990 * they are kept together above, to simplify freeing. 2991 */ 2992out: 2993 NG_RESPOND_MSG(error, here, item, resp); 2994 if (msg) 2995 NG_FREE_MSG(msg); 2996 return (error); 2997} 2998 2999/************************************************************************ 3000 Queue element get/free routines 3001************************************************************************/ 3002 3003uma_zone_t ng_qzone; 3004static int maxalloc = 4096;/* limit the damage of a leak */ 3005static int maxdata = 512; /* limit the damage of a DoS */ 3006static int useddata = 0; 3007 3008TUNABLE_INT("net.graph.maxalloc", &maxalloc); 3009SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc, 3010 0, "Maximum number of queue items to allocate"); 3011TUNABLE_INT("net.graph.maxdata", &maxdata); 3012SYSCTL_INT(_net_graph, OID_AUTO, maxdata, CTLFLAG_RW | CTLFLAG_TUN, &maxdata, 3013 0, "Maximum number of queue data items to allocate"); 3014 3015#ifdef NETGRAPH_DEBUG 3016static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist); 3017static int allocated; /* number of items malloc'd */ 3018#endif 3019 3020/* 3021 * Get a queue entry. 3022 * This is usually called when a packet first enters netgraph. 3023 * By definition, this is usually from an interrupt, or from a user. 3024 * Users are not so important, but try be quick for the times that it's 3025 * an interrupt. 3026 */ 3027static __inline item_p 3028ng_getqblk(int flags) 3029{ 3030 item_p item = NULL; 3031 int wait; 3032 3033 wait = (flags & NG_WAITOK) ? M_WAITOK : M_NOWAIT; 3034 3035 item = uma_zalloc(ng_qzone, wait | M_ZERO); 3036 3037#ifdef NETGRAPH_DEBUG 3038 if (item) { 3039 mtx_lock(&ngq_mtx); 3040 TAILQ_INSERT_TAIL(&ng_itemlist, item, all); 3041 allocated++; 3042 mtx_unlock(&ngq_mtx); 3043 } 3044#endif 3045 3046 return (item); 3047} 3048 3049/* 3050 * Release a queue entry 3051 */ 3052void 3053ng_free_item(item_p item) 3054{ 3055 /* 3056 * The item may hold resources on it's own. We need to free 3057 * these before we can free the item. What they are depends upon 3058 * what kind of item it is. it is important that nodes zero 3059 * out pointers to resources that they remove from the item 3060 * or we release them again here. 3061 */ 3062 switch (item->el_flags & NGQF_TYPE) { 3063 case NGQF_DATA: 3064 atomic_subtract_int(&useddata, 1); 3065 /* If we have an mbuf still attached.. */ 3066 NG_FREE_M(_NGI_M(item)); 3067 break; 3068 case NGQF_MESG: 3069 _NGI_RETADDR(item) = 0; 3070 NG_FREE_MSG(_NGI_MSG(item)); 3071 break; 3072 case NGQF_FN: 3073 case NGQF_FN2: 3074 /* nothing to free really, */ 3075 _NGI_FN(item) = NULL; 3076 _NGI_ARG1(item) = NULL; 3077 _NGI_ARG2(item) = 0; 3078 break; 3079 } 3080 /* If we still have a node or hook referenced... */ 3081 _NGI_CLR_NODE(item); 3082 _NGI_CLR_HOOK(item); 3083 3084#ifdef NETGRAPH_DEBUG 3085 mtx_lock(&ngq_mtx); 3086 TAILQ_REMOVE(&ng_itemlist, item, all); 3087 allocated--; 3088 mtx_unlock(&ngq_mtx); 3089#endif 3090 uma_zfree(ng_qzone, item); 3091} 3092 3093/************************************************************************ 3094 Module routines 3095************************************************************************/ 3096 3097/* 3098 * Handle the loading/unloading of a netgraph node type module 3099 */ 3100int 3101ng_mod_event(module_t mod, int event, void *data) 3102{ 3103 struct ng_type *const type = data; 3104 int s, error = 0; 3105 3106 switch (event) { 3107 case MOD_LOAD: 3108 3109 /* Register new netgraph node type */ 3110 s = splnet(); 3111 if ((error = ng_newtype(type)) != 0) { 3112 splx(s); 3113 break; 3114 } 3115 3116 /* Call type specific code */ 3117 if (type->mod_event != NULL) 3118 if ((error = (*type->mod_event)(mod, event, data))) { 3119 mtx_lock(&ng_typelist_mtx); 3120 type->refs--; /* undo it */ 3121 LIST_REMOVE(type, types); 3122 mtx_unlock(&ng_typelist_mtx); 3123 } 3124 splx(s); 3125 break; 3126 3127 case MOD_UNLOAD: 3128 s = splnet(); 3129 if (type->refs > 1) { /* make sure no nodes exist! */ 3130 error = EBUSY; 3131 } else { 3132 if (type->refs == 0) { 3133 /* failed load, nothing to undo */ 3134 splx(s); 3135 break; 3136 } 3137 if (type->mod_event != NULL) { /* check with type */ 3138 error = (*type->mod_event)(mod, event, data); 3139 if (error != 0) { /* type refuses.. */ 3140 splx(s); 3141 break; 3142 } 3143 } 3144 mtx_lock(&ng_typelist_mtx); 3145 LIST_REMOVE(type, types); 3146 mtx_unlock(&ng_typelist_mtx); 3147 } 3148 splx(s); 3149 break; 3150 3151 default: 3152 if (type->mod_event != NULL) 3153 error = (*type->mod_event)(mod, event, data); 3154 else 3155 error = EOPNOTSUPP; /* XXX ? */ 3156 break; 3157 } 3158 return (error); 3159} 3160 3161/* 3162 * Handle loading and unloading for this code. 3163 * The only thing we need to link into is the NETISR strucure. 3164 */ 3165static int 3166ngb_mod_event(module_t mod, int event, void *data) 3167{ 3168 int error = 0; 3169 3170 switch (event) { 3171 case MOD_LOAD: 3172 /* Initialize everything. */ 3173 NG_WORKLIST_LOCK_INIT(); 3174 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL, 3175 MTX_DEF); 3176 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL, 3177 MTX_DEF); 3178 mtx_init(&ng_namehash_mtx, "netgraph namehash mutex", NULL, 3179 MTX_DEF); 3180 mtx_init(&ng_topo_mtx, "netgraph topology mutex", NULL, 3181 MTX_DEF); 3182#ifdef NETGRAPH_DEBUG 3183 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL, 3184 MTX_DEF); 3185 mtx_init(&ngq_mtx, "netgraph item list mutex", NULL, 3186 MTX_DEF); 3187#endif 3188 ng_qzone = uma_zcreate("NetGraph items", sizeof(struct ng_item), 3189 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0); 3190 uma_zone_set_max(ng_qzone, maxalloc); 3191 netisr_register(NETISR_NETGRAPH, (netisr_t *)ngintr, NULL, 3192 NETISR_MPSAFE); 3193 break; 3194 case MOD_UNLOAD: 3195 /* You can't unload it because an interface may be using it. */ 3196 error = EBUSY; 3197 break; 3198 default: 3199 error = EOPNOTSUPP; 3200 break; 3201 } 3202 return (error); 3203} 3204 3205static moduledata_t netgraph_mod = { 3206 "netgraph", 3207 ngb_mod_event, 3208 (NULL) 3209}; 3210DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_MIDDLE); 3211SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family"); 3212SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,""); 3213SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, ""); 3214 3215#ifdef NETGRAPH_DEBUG 3216void 3217dumphook (hook_p hook, char *file, int line) 3218{ 3219 printf("hook: name %s, %d refs, Last touched:\n", 3220 _NG_HOOK_NAME(hook), hook->hk_refs); 3221 printf(" Last active @ %s, line %d\n", 3222 hook->lastfile, hook->lastline); 3223 if (line) { 3224 printf(" problem discovered at file %s, line %d\n", file, line); 3225 } 3226} 3227 3228void 3229dumpnode(node_p node, char *file, int line) 3230{ 3231 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n", 3232 _NG_NODE_ID(node), node->nd_type->name, 3233 node->nd_numhooks, node->nd_flags, 3234 node->nd_refs, node->nd_name); 3235 printf(" Last active @ %s, line %d\n", 3236 node->lastfile, node->lastline); 3237 if (line) { 3238 printf(" problem discovered at file %s, line %d\n", file, line); 3239 } 3240} 3241 3242void 3243dumpitem(item_p item, char *file, int line) 3244{ 3245 printf(" ACTIVE item, last used at %s, line %d", 3246 item->lastfile, item->lastline); 3247 switch(item->el_flags & NGQF_TYPE) { 3248 case NGQF_DATA: 3249 printf(" - [data]\n"); 3250 break; 3251 case NGQF_MESG: 3252 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item)); 3253 break; 3254 case NGQF_FN: 3255 printf(" - fn@%p (%p, %p, %p, %d (%x))\n", 3256 _NGI_FN(item), 3257 _NGI_NODE(item), 3258 _NGI_HOOK(item), 3259 item->body.fn.fn_arg1, 3260 item->body.fn.fn_arg2, 3261 item->body.fn.fn_arg2); 3262 break; 3263 case NGQF_FN2: 3264 printf(" - fn2@%p (%p, %p, %p, %d (%x))\n", 3265 _NGI_FN2(item), 3266 _NGI_NODE(item), 3267 _NGI_HOOK(item), 3268 item->body.fn.fn_arg1, 3269 item->body.fn.fn_arg2, 3270 item->body.fn.fn_arg2); 3271 break; 3272 } 3273 if (line) { 3274 printf(" problem discovered at file %s, line %d\n", file, line); 3275 if (_NGI_NODE(item)) { 3276 printf("node %p ([%x])\n", 3277 _NGI_NODE(item), ng_node2ID(_NGI_NODE(item))); 3278 } 3279 } 3280} 3281 3282static void 3283ng_dumpitems(void) 3284{ 3285 item_p item; 3286 int i = 1; 3287 TAILQ_FOREACH(item, &ng_itemlist, all) { 3288 printf("[%d] ", i++); 3289 dumpitem(item, NULL, 0); 3290 } 3291} 3292 3293static void 3294ng_dumpnodes(void) 3295{ 3296 node_p node; 3297 int i = 1; 3298 mtx_lock(&ng_nodelist_mtx); 3299 SLIST_FOREACH(node, &ng_allnodes, nd_all) { 3300 printf("[%d] ", i++); 3301 dumpnode(node, NULL, 0); 3302 } 3303 mtx_unlock(&ng_nodelist_mtx); 3304} 3305 3306static void 3307ng_dumphooks(void) 3308{ 3309 hook_p hook; 3310 int i = 1; 3311 mtx_lock(&ng_nodelist_mtx); 3312 SLIST_FOREACH(hook, &ng_allhooks, hk_all) { 3313 printf("[%d] ", i++); 3314 dumphook(hook, NULL, 0); 3315 } 3316 mtx_unlock(&ng_nodelist_mtx); 3317} 3318 3319static int 3320sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS) 3321{ 3322 int error; 3323 int val; 3324 int i; 3325 3326 val = allocated; 3327 i = 1; 3328 error = sysctl_handle_int(oidp, &val, 0, req); 3329 if (error != 0 || req->newptr == NULL) 3330 return (error); 3331 if (val == 42) { 3332 ng_dumpitems(); 3333 ng_dumpnodes(); 3334 ng_dumphooks(); 3335 } 3336 return (0); 3337} 3338 3339SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW, 3340 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items"); 3341#endif /* NETGRAPH_DEBUG */ 3342 3343 3344/*********************************************************************** 3345* Worklist routines 3346**********************************************************************/ 3347/* NETISR thread enters here */ 3348/* 3349 * Pick a node off the list of nodes with work, 3350 * try get an item to process off it. 3351 * If there are no more, remove the node from the list. 3352 */ 3353static void 3354ngintr(void) 3355{ 3356 item_p item; 3357 node_p node = NULL; 3358 3359 for (;;) { 3360 NG_WORKLIST_LOCK(); 3361 node = TAILQ_FIRST(&ng_worklist); 3362 if (!node) { 3363 NG_WORKLIST_UNLOCK(); 3364 break; 3365 } 3366 node->nd_flags &= ~NGF_WORKQ; 3367 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3368 NG_WORKLIST_UNLOCK(); 3369 CTR3(KTR_NET, "%20s: node [%x] (%p) taken off worklist", 3370 __func__, node->nd_ID, node); 3371 /* 3372 * We have the node. We also take over the reference 3373 * that the list had on it. 3374 * Now process as much as you can, until it won't 3375 * let you have another item off the queue. 3376 * All this time, keep the reference 3377 * that lets us be sure that the node still exists. 3378 * Let the reference go at the last minute. 3379 */ 3380 for (;;) { 3381 int rw; 3382 3383 NG_QUEUE_LOCK(&node->nd_input_queue); 3384 item = ng_dequeue(&node->nd_input_queue, &rw); 3385 if (item == NULL) { 3386 NG_QUEUE_UNLOCK(&node->nd_input_queue); 3387 break; /* go look for another node */ 3388 } else { 3389 NG_QUEUE_UNLOCK(&node->nd_input_queue); 3390 NGI_GET_NODE(item, node); /* zaps stored node */ 3391 ng_apply_item(node, item, rw); 3392 NG_NODE_UNREF(node); 3393 } 3394 } 3395 NG_NODE_UNREF(node); 3396 } 3397} 3398 3399static void 3400ng_worklist_remove(node_p node) 3401{ 3402 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED); 3403 3404 NG_WORKLIST_LOCK(); 3405 if (node->nd_flags & NGF_WORKQ) { 3406 node->nd_flags &= ~NGF_WORKQ; 3407 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3408 NG_WORKLIST_UNLOCK(); 3409 NG_NODE_UNREF(node); 3410 CTR3(KTR_NET, "%20s: node [%x] (%p) removed from worklist", 3411 __func__, node->nd_ID, node); 3412 } else { 3413 NG_WORKLIST_UNLOCK(); 3414 } 3415} 3416 3417/* 3418 * XXX 3419 * It's posible that a debugging NG_NODE_REF may need 3420 * to be outside the mutex zone 3421 */ 3422static void 3423ng_setisr(node_p node) 3424{ 3425 3426 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED); 3427 3428 if ((node->nd_flags & NGF_WORKQ) == 0) { 3429 /* 3430 * If we are not already on the work queue, 3431 * then put us on. 3432 */ 3433 node->nd_flags |= NGF_WORKQ; 3434 NG_WORKLIST_LOCK(); 3435 TAILQ_INSERT_TAIL(&ng_worklist, node, nd_work); 3436 NG_WORKLIST_UNLOCK(); 3437 NG_NODE_REF(node); /* XXX fafe in mutex? */ 3438 CTR3(KTR_NET, "%20s: node [%x] (%p) put on worklist", __func__, 3439 node->nd_ID, node); 3440 } else 3441 CTR3(KTR_NET, "%20s: node [%x] (%p) already on worklist", 3442 __func__, node->nd_ID, node); 3443 schednetisr(NETISR_NETGRAPH); 3444} 3445 3446 3447/*********************************************************************** 3448* Externally useable functions to set up a queue item ready for sending 3449***********************************************************************/ 3450 3451#ifdef NETGRAPH_DEBUG 3452#define ITEM_DEBUG_CHECKS \ 3453 do { \ 3454 if (NGI_NODE(item) ) { \ 3455 printf("item already has node"); \ 3456 kdb_enter(KDB_WHY_NETGRAPH, "has node"); \ 3457 NGI_CLR_NODE(item); \ 3458 } \ 3459 if (NGI_HOOK(item) ) { \ 3460 printf("item already has hook"); \ 3461 kdb_enter(KDB_WHY_NETGRAPH, "has hook"); \ 3462 NGI_CLR_HOOK(item); \ 3463 } \ 3464 } while (0) 3465#else 3466#define ITEM_DEBUG_CHECKS 3467#endif 3468 3469/* 3470 * Put mbuf into the item. 3471 * Hook and node references will be removed when the item is dequeued. 3472 * (or equivalent) 3473 * (XXX) Unsafe because no reference held by peer on remote node. 3474 * remote node might go away in this timescale. 3475 * We know the hooks can't go away because that would require getting 3476 * a writer item on both nodes and we must have at least a reader 3477 * here to be able to do this. 3478 * Note that the hook loaded is the REMOTE hook. 3479 * 3480 * This is possibly in the critical path for new data. 3481 */ 3482item_p 3483ng_package_data(struct mbuf *m, int flags) 3484{ 3485 item_p item; 3486 3487 if (atomic_fetchadd_int(&useddata, 1) >= maxdata) { 3488 atomic_subtract_int(&useddata, 1); 3489 NG_FREE_M(m); 3490 return (NULL); 3491 } 3492 if ((item = ng_getqblk(flags)) == NULL) { 3493 NG_FREE_M(m); 3494 return (NULL); 3495 } 3496 ITEM_DEBUG_CHECKS; 3497 item->el_flags = NGQF_DATA | NGQF_READER; 3498 NGI_M(item) = m; 3499 return (item); 3500} 3501 3502/* 3503 * Allocate a queue item and put items into it.. 3504 * Evaluate the address as this will be needed to queue it and 3505 * to work out what some of the fields should be. 3506 * Hook and node references will be removed when the item is dequeued. 3507 * (or equivalent) 3508 */ 3509item_p 3510ng_package_msg(struct ng_mesg *msg, int flags) 3511{ 3512 item_p item; 3513 3514 if ((item = ng_getqblk(flags)) == NULL) { 3515 NG_FREE_MSG(msg); 3516 return (NULL); 3517 } 3518 ITEM_DEBUG_CHECKS; 3519 /* Messages items count as writers unless explicitly exempted. */ 3520 if (msg->header.cmd & NGM_READONLY) 3521 item->el_flags = NGQF_MESG | NGQF_READER; 3522 else 3523 item->el_flags = NGQF_MESG | NGQF_WRITER; 3524 /* 3525 * Set the current lasthook into the queue item 3526 */ 3527 NGI_MSG(item) = msg; 3528 NGI_RETADDR(item) = 0; 3529 return (item); 3530} 3531 3532 3533 3534#define SET_RETADDR(item, here, retaddr) \ 3535 do { /* Data or fn items don't have retaddrs */ \ 3536 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \ 3537 if (retaddr) { \ 3538 NGI_RETADDR(item) = retaddr; \ 3539 } else { \ 3540 /* \ 3541 * The old return address should be ok. \ 3542 * If there isn't one, use the address \ 3543 * here. \ 3544 */ \ 3545 if (NGI_RETADDR(item) == 0) { \ 3546 NGI_RETADDR(item) \ 3547 = ng_node2ID(here); \ 3548 } \ 3549 } \ 3550 } \ 3551 } while (0) 3552 3553int 3554ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr) 3555{ 3556 hook_p peer; 3557 node_p peernode; 3558 ITEM_DEBUG_CHECKS; 3559 /* 3560 * Quick sanity check.. 3561 * Since a hook holds a reference on it's node, once we know 3562 * that the peer is still connected (even if invalid,) we know 3563 * that the peer node is present, though maybe invalid. 3564 */ 3565 if ((hook == NULL) 3566 || NG_HOOK_NOT_VALID(hook) 3567 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)) 3568 || NG_NODE_NOT_VALID(NG_PEER_NODE(hook))) { 3569 NG_FREE_ITEM(item); 3570 TRAP_ERROR(); 3571 return (ENETDOWN); 3572 } 3573 3574 /* 3575 * Transfer our interest to the other (peer) end. 3576 */ 3577 peer = NG_HOOK_PEER(hook); 3578 NG_HOOK_REF(peer); 3579 NGI_SET_HOOK(item, peer); 3580 peernode = NG_PEER_NODE(hook); 3581 NG_NODE_REF(peernode); 3582 NGI_SET_NODE(item, peernode); 3583 SET_RETADDR(item, here, retaddr); 3584 return (0); 3585} 3586 3587int 3588ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr) 3589{ 3590 node_p dest = NULL; 3591 hook_p hook = NULL; 3592 int error; 3593 3594 ITEM_DEBUG_CHECKS; 3595 /* 3596 * Note that ng_path2noderef increments the reference count 3597 * on the node for us if it finds one. So we don't have to. 3598 */ 3599 error = ng_path2noderef(here, address, &dest, &hook); 3600 if (error) { 3601 NG_FREE_ITEM(item); 3602 return (error); 3603 } 3604 NGI_SET_NODE(item, dest); 3605 if ( hook) { 3606 NG_HOOK_REF(hook); /* don't let it go while on the queue */ 3607 NGI_SET_HOOK(item, hook); 3608 } 3609 SET_RETADDR(item, here, retaddr); 3610 return (0); 3611} 3612 3613int 3614ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr) 3615{ 3616 node_p dest; 3617 3618 ITEM_DEBUG_CHECKS; 3619 /* 3620 * Find the target node. 3621 */ 3622 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */ 3623 if (dest == NULL) { 3624 NG_FREE_ITEM(item); 3625 TRAP_ERROR(); 3626 return(EINVAL); 3627 } 3628 /* Fill out the contents */ 3629 NGI_SET_NODE(item, dest); 3630 NGI_CLR_HOOK(item); 3631 SET_RETADDR(item, here, retaddr); 3632 return (0); 3633} 3634 3635/* 3636 * special case to send a message to self (e.g. destroy node) 3637 * Possibly indicate an arrival hook too. 3638 * Useful for removing that hook :-) 3639 */ 3640item_p 3641ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg) 3642{ 3643 item_p item; 3644 3645 /* 3646 * Find the target node. 3647 * If there is a HOOK argument, then use that in preference 3648 * to the address. 3649 */ 3650 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL) { 3651 NG_FREE_MSG(msg); 3652 return (NULL); 3653 } 3654 3655 /* Fill out the contents */ 3656 item->el_flags = NGQF_MESG | NGQF_WRITER; 3657 NG_NODE_REF(here); 3658 NGI_SET_NODE(item, here); 3659 if (hook) { 3660 NG_HOOK_REF(hook); 3661 NGI_SET_HOOK(item, hook); 3662 } 3663 NGI_MSG(item) = msg; 3664 NGI_RETADDR(item) = ng_node2ID(here); 3665 return (item); 3666} 3667 3668/* 3669 * Send ng_item_fn function call to the specified node. 3670 */ 3671 3672int 3673ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2) 3674{ 3675 3676 return ng_send_fn1(node, hook, fn, arg1, arg2, NG_NOFLAGS); 3677} 3678 3679int 3680ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2, 3681 int flags) 3682{ 3683 item_p item; 3684 3685 if ((item = ng_getqblk(flags)) == NULL) { 3686 return (ENOMEM); 3687 } 3688 item->el_flags = NGQF_FN | NGQF_WRITER; 3689 NG_NODE_REF(node); /* and one for the item */ 3690 NGI_SET_NODE(item, node); 3691 if (hook) { 3692 NG_HOOK_REF(hook); 3693 NGI_SET_HOOK(item, hook); 3694 } 3695 NGI_FN(item) = fn; 3696 NGI_ARG1(item) = arg1; 3697 NGI_ARG2(item) = arg2; 3698 return(ng_snd_item(item, flags)); 3699} 3700 3701/* 3702 * Send ng_item_fn2 function call to the specified node. 3703 * 3704 * If an optional pitem parameter is supplied, its apply 3705 * callback will be copied to the new item. If also NG_REUSE_ITEM 3706 * flag is set, no new item will be allocated, but pitem will 3707 * be used. 3708 */ 3709int 3710ng_send_fn2(node_p node, hook_p hook, item_p pitem, ng_item_fn2 *fn, void *arg1, 3711 int arg2, int flags) 3712{ 3713 item_p item; 3714 3715 KASSERT((pitem != NULL || (flags & NG_REUSE_ITEM) == 0), 3716 ("%s: NG_REUSE_ITEM but no pitem", __func__)); 3717 3718 /* 3719 * Allocate a new item if no supplied or 3720 * if we can't use supplied one. 3721 */ 3722 if (pitem == NULL || (flags & NG_REUSE_ITEM) == 0) { 3723 if ((item = ng_getqblk(flags)) == NULL) 3724 return (ENOMEM); 3725 } else { 3726 if ((pitem->el_flags & NGQF_TYPE) == NGQF_DATA) 3727 atomic_subtract_int(&useddata, 1); 3728 item = pitem; 3729 } 3730 3731 item->el_flags = NGQF_FN2 | NGQF_WRITER; 3732 NG_NODE_REF(node); /* and one for the item */ 3733 NGI_SET_NODE(item, node); 3734 if (hook) { 3735 NG_HOOK_REF(hook); 3736 NGI_SET_HOOK(item, hook); 3737 } 3738 NGI_FN2(item) = fn; 3739 NGI_ARG1(item) = arg1; 3740 NGI_ARG2(item) = arg2; 3741 if (pitem != NULL && (flags & NG_REUSE_ITEM) == 0) 3742 item->apply = pitem->apply; 3743 return(ng_snd_item(item, flags)); 3744} 3745 3746/* 3747 * Official timeout routines for Netgraph nodes. 3748 */ 3749static void 3750ng_callout_trampoline(void *arg) 3751{ 3752 item_p item = arg; 3753 3754 ng_snd_item(item, 0); 3755} 3756 3757 3758int 3759ng_callout(struct callout *c, node_p node, hook_p hook, int ticks, 3760 ng_item_fn *fn, void * arg1, int arg2) 3761{ 3762 item_p item, oitem; 3763 3764 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL) 3765 return (ENOMEM); 3766 3767 item->el_flags = NGQF_FN | NGQF_WRITER; 3768 NG_NODE_REF(node); /* and one for the item */ 3769 NGI_SET_NODE(item, node); 3770 if (hook) { 3771 NG_HOOK_REF(hook); 3772 NGI_SET_HOOK(item, hook); 3773 } 3774 NGI_FN(item) = fn; 3775 NGI_ARG1(item) = arg1; 3776 NGI_ARG2(item) = arg2; 3777 oitem = c->c_arg; 3778 if (callout_reset(c, ticks, &ng_callout_trampoline, item) == 1 && 3779 oitem != NULL) 3780 NG_FREE_ITEM(oitem); 3781 return (0); 3782} 3783 3784/* A special modified version of untimeout() */ 3785int 3786ng_uncallout(struct callout *c, node_p node) 3787{ 3788 item_p item; 3789 int rval; 3790 3791 KASSERT(c != NULL, ("ng_uncallout: NULL callout")); 3792 KASSERT(node != NULL, ("ng_uncallout: NULL node")); 3793 3794 rval = callout_stop(c); 3795 item = c->c_arg; 3796 /* Do an extra check */ 3797 if ((rval > 0) && (c->c_func == &ng_callout_trampoline) && 3798 (NGI_NODE(item) == node)) { 3799 /* 3800 * We successfully removed it from the queue before it ran 3801 * So now we need to unreference everything that was 3802 * given extra references. (NG_FREE_ITEM does this). 3803 */ 3804 NG_FREE_ITEM(item); 3805 } 3806 c->c_arg = NULL; 3807 3808 return (rval); 3809} 3810 3811/* 3812 * Set the address, if none given, give the node here. 3813 */ 3814void 3815ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr) 3816{ 3817 if (retaddr) { 3818 NGI_RETADDR(item) = retaddr; 3819 } else { 3820 /* 3821 * The old return address should be ok. 3822 * If there isn't one, use the address here. 3823 */ 3824 NGI_RETADDR(item) = ng_node2ID(here); 3825 } 3826} 3827 3828#define TESTING 3829#ifdef TESTING 3830/* just test all the macros */ 3831void 3832ng_macro_test(item_p item); 3833void 3834ng_macro_test(item_p item) 3835{ 3836 node_p node = NULL; 3837 hook_p hook = NULL; 3838 struct mbuf *m; 3839 struct ng_mesg *msg; 3840 ng_ID_t retaddr; 3841 int error; 3842 3843 NGI_GET_M(item, m); 3844 NGI_GET_MSG(item, msg); 3845 retaddr = NGI_RETADDR(item); 3846 NG_SEND_DATA(error, hook, m, NULL); 3847 NG_SEND_DATA_ONLY(error, hook, m); 3848 NG_FWD_NEW_DATA(error, item, hook, m); 3849 NG_FWD_ITEM_HOOK(error, item, hook); 3850 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr); 3851 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr); 3852 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr); 3853 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr); 3854} 3855#endif /* TESTING */ 3856 3857