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Vendor import of netgraph from FreeBSD-current 20080626
[dragonfly.git] / sys / netgraph7 / ng_base.c
blob2e410f5ccb1ddbf20a4c4ced634504b2e709bcae
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: src/sys/netgraph/ng_base.c,v 1.159 2008/04/19 05:30:49 mav Exp $
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 #include <machine/cpu.h>
65
66 #include <net/netisr.h>
67
68 #include <netgraph/ng_message.h>
69 #include <netgraph/netgraph.h>
70 #include <netgraph/ng_parse.h>
71
72 MODULE_VERSION(netgraph, NG_ABI_VERSION);
73
74 /* Mutex to protect topology events. */
75 static struct mtx ng_topo_mtx;
76
77 #ifdef NETGRAPH_DEBUG
78 static struct mtx ng_nodelist_mtx; /* protects global node/hook lists */
79 static struct mtx ngq_mtx; /* protects the queue item list */
80
81 static SLIST_HEAD(, ng_node) ng_allnodes;
82 static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */
83 static SLIST_HEAD(, ng_hook) ng_allhooks;
84 static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */
85
86 static void ng_dumpitems(void);
87 static void ng_dumpnodes(void);
88 static void ng_dumphooks(void);
89
90 #endif /* NETGRAPH_DEBUG */
91 /*
92 * DEAD versions of the structures.
93 * In order to avoid races, it is sometimes neccesary to point
94 * at SOMETHING even though theoretically, the current entity is
95 * INVALID. Use these to avoid these races.
96 */
97 struct ng_type ng_deadtype = {
98 NG_ABI_VERSION,
99 "dead",
100 NULL, /* modevent */
101 NULL, /* constructor */
102 NULL, /* rcvmsg */
103 NULL, /* shutdown */
104 NULL, /* newhook */
105 NULL, /* findhook */
106 NULL, /* connect */
107 NULL, /* rcvdata */
108 NULL, /* disconnect */
109 NULL, /* cmdlist */
110 };
111
112 struct ng_node ng_deadnode = {
113 "dead",
114 &ng_deadtype,
115 NGF_INVALID,
116 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 { 0,
123 0,
124 {}, /* should never use! (should hang) */
125 {}, /* workqueue entry */
126 STAILQ_HEAD_INITIALIZER(ng_deadnode.nd_input_queue.queue),
127 },
128 1, /* refs */
129 #ifdef NETGRAPH_DEBUG
130 ND_MAGIC,
131 __FILE__,
132 __LINE__,
133 {NULL}
134 #endif /* NETGRAPH_DEBUG */
135 };
136
137 struct ng_hook ng_deadhook = {
138 "dead",
139 NULL, /* private */
140 HK_INVALID | HK_DEAD,
141 0, /* undefined data link type */
142 &ng_deadhook, /* Peer is self */
143 &ng_deadnode, /* attached to deadnode */
144 {}, /* hooks list */
145 NULL, /* override rcvmsg() */
146 NULL, /* override rcvdata() */
147 1, /* refs always >= 1 */
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 */
160 static STAILQ_HEAD(, ng_node) ng_worklist = STAILQ_HEAD_INITIALIZER(ng_worklist);
161 static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */
162
163 /* List of installed types */
164 static LIST_HEAD(, ng_type) ng_typelist;
165 static 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 */
170 static LIST_HEAD(, ng_node) ng_ID_hash[NG_ID_HASH_SIZE];
171 static 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 */
187 static LIST_HEAD(, ng_node) ng_name_hash[NG_NAME_HASH_SIZE];
188 static 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 */
200 static int ng_add_hook(node_p node, const char *name, hook_p * hookp);
201 static int ng_generic_msg(node_p here, item_p item, hook_p lasthook);
202 static ng_ID_t ng_decodeidname(const char *name);
203 static int ngb_mod_event(module_t mod, int event, void *data);
204 static void ng_worklist_add(node_p node);
205 static void ngintr(void);
206 static int ng_apply_item(node_p node, item_p item, int rw);
207 static void ng_flush_input_queue(node_p node);
208 static node_p ng_ID2noderef(ng_ID_t ID);
209 static int ng_con_nodes(item_p item, node_p node, const char *name,
210 node_p node2, const char *name2);
211 static int ng_con_part2(node_p node, item_p item, hook_p hook);
212 static int ng_con_part3(node_p node, item_p item, hook_p hook);
213 static int ng_mkpeer(node_p node, const char *name,
214 const char *name2, char *type);
215
216 /* Imported, these used to be externally visible, some may go back. */
217 void ng_destroy_hook(hook_p hook);
218 node_p ng_name2noderef(node_p node, const char *name);
219 int ng_path2noderef(node_p here, const char *path,
220 node_p *dest, hook_p *lasthook);
221 int ng_make_node(const char *type, node_p *nodepp);
222 int ng_path_parse(char *addr, char **node, char **path, char **hook);
223 void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3);
224 void ng_unname(node_p node);
225
226
227 /* Our own netgraph malloc type */
228 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages");
229 MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures");
230 MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures");
231 MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", "netgraph item structures");
232 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage");
233
234 /* Should not be visible outside this file */
235
236 #define _NG_ALLOC_HOOK(hook) \
237 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO)
238 #define _NG_ALLOC_NODE(node) \
239 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO)
240
241 #define NG_QUEUE_LOCK_INIT(n) \
242 mtx_init(&(n)->q_mtx, "ng_node", NULL, MTX_DEF)
243 #define NG_QUEUE_LOCK(n) \
244 mtx_lock(&(n)->q_mtx)
245 #define NG_QUEUE_UNLOCK(n) \
246 mtx_unlock(&(n)->q_mtx)
247 #define NG_WORKLIST_LOCK_INIT() \
248 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_DEF)
249 #define NG_WORKLIST_LOCK() \
250 mtx_lock(&ng_worklist_mtx)
251 #define NG_WORKLIST_UNLOCK() \
252 mtx_unlock(&ng_worklist_mtx)
253
254 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/
255 /*
256 * In debug mode:
257 * In an attempt to help track reference count screwups
258 * we do not free objects back to the malloc system, but keep them
259 * in a local cache where we can examine them and keep information safely
260 * after they have been freed.
261 * We use this scheme for nodes and hooks, and to some extent for items.
262 */
263 static __inline hook_p
264 ng_alloc_hook(void)
265 {
266 hook_p hook;
267 SLIST_ENTRY(ng_hook) temp;
268 mtx_lock(&ng_nodelist_mtx);
269 hook = LIST_FIRST(&ng_freehooks);
270 if (hook) {
271 LIST_REMOVE(hook, hk_hooks);
272 bcopy(&hook->hk_all, &temp, sizeof(temp));
273 bzero(hook, sizeof(struct ng_hook));
274 bcopy(&temp, &hook->hk_all, sizeof(temp));
275 mtx_unlock(&ng_nodelist_mtx);
276 hook->hk_magic = HK_MAGIC;
277 } else {
278 mtx_unlock(&ng_nodelist_mtx);
279 _NG_ALLOC_HOOK(hook);
280 if (hook) {
281 hook->hk_magic = HK_MAGIC;
282 mtx_lock(&ng_nodelist_mtx);
283 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all);
284 mtx_unlock(&ng_nodelist_mtx);
285 }
286 }
287 return (hook);
288 }
289
290 static __inline node_p
291 ng_alloc_node(void)
292 {
293 node_p node;
294 SLIST_ENTRY(ng_node) temp;
295 mtx_lock(&ng_nodelist_mtx);
296 node = LIST_FIRST(&ng_freenodes);
297 if (node) {
298 LIST_REMOVE(node, nd_nodes);
299 bcopy(&node->nd_all, &temp, sizeof(temp));
300 bzero(node, sizeof(struct ng_node));
301 bcopy(&temp, &node->nd_all, sizeof(temp));
302 mtx_unlock(&ng_nodelist_mtx);
303 node->nd_magic = ND_MAGIC;
304 } else {
305 mtx_unlock(&ng_nodelist_mtx);
306 _NG_ALLOC_NODE(node);
307 if (node) {
308 node->nd_magic = ND_MAGIC;
309 mtx_lock(&ng_nodelist_mtx);
310 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all);
311 mtx_unlock(&ng_nodelist_mtx);
312 }
313 }
314 return (node);
315 }
316
317 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0)
318 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0)
319
320
321 #define NG_FREE_HOOK(hook) \
322 do { \
323 mtx_lock(&ng_nodelist_mtx); \
324 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \
325 hook->hk_magic = 0; \
326 mtx_unlock(&ng_nodelist_mtx); \
327 } while (0)
328
329 #define NG_FREE_NODE(node) \
330 do { \
331 mtx_lock(&ng_nodelist_mtx); \
332 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \
333 node->nd_magic = 0; \
334 mtx_unlock(&ng_nodelist_mtx); \
335 } while (0)
336
337 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
338
339 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook)
340 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node)
341
342 #define NG_FREE_HOOK(hook) do { FREE((hook), M_NETGRAPH_HOOK); } while (0)
343 #define NG_FREE_NODE(node) do { FREE((node), M_NETGRAPH_NODE); } while (0)
344
345 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
346
347 /* Set this to kdb_enter("X") to catch all errors as they occur */
348 #ifndef TRAP_ERROR
349 #define TRAP_ERROR()
350 #endif
351
352 static ng_ID_t nextID = 1;
353
354 #ifdef INVARIANTS
355 #define CHECK_DATA_MBUF(m) do { \
356 struct mbuf *n; \
357 int total; \
358 \
359 M_ASSERTPKTHDR(m); \
360 for (total = 0, n = (m); n != NULL; n = n->m_next) { \
361 total += n->m_len; \
362 if (n->m_nextpkt != NULL) \
363 panic("%s: m_nextpkt", __func__); \
364 } \
365 \
366 if ((m)->m_pkthdr.len != total) { \
367 panic("%s: %d != %d", \
368 __func__, (m)->m_pkthdr.len, total); \
369 } \
370 } while (0)
371 #else
372 #define CHECK_DATA_MBUF(m)
373 #endif
374
375 #define ERROUT(x) do { error = (x); goto done; } while (0)
376
377 /************************************************************************
378 Parse type definitions for generic messages
379 ************************************************************************/
380
381 /* Handy structure parse type defining macro */
382 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \
383 static const struct ng_parse_struct_field \
384 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \
385 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \
386 &ng_parse_struct_type, \
387 &ng_ ## lo ## _type_fields \
388 }
389
390 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ());
391 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ());
392 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ());
393 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ());
394 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ());
395 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ());
396 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type));
397
398 /* Get length of an array when the length is stored as a 32 bit
399 value immediately preceding the array -- as with struct namelist
400 and struct typelist. */
401 static int
402 ng_generic_list_getLength(const struct ng_parse_type *type,
403 const u_char *start, const u_char *buf)
404 {
405 return *((const u_int32_t *)(buf - 4));
406 }
407
408 /* Get length of the array of struct linkinfo inside a struct hooklist */
409 static int
410 ng_generic_linkinfo_getLength(const struct ng_parse_type *type,
411 const u_char *start, const u_char *buf)
412 {
413 const struct hooklist *hl = (const struct hooklist *)start;
414
415 return hl->nodeinfo.hooks;
416 }
417
418 /* Array type for a variable length array of struct namelist */
419 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = {
420 &ng_generic_nodeinfo_type,
421 &ng_generic_list_getLength
422 };
423 static const struct ng_parse_type ng_generic_nodeinfoarray_type = {
424 &ng_parse_array_type,
425 &ng_nodeinfoarray_type_info
426 };
427
428 /* Array type for a variable length array of struct typelist */
429 static const struct ng_parse_array_info ng_typeinfoarray_type_info = {
430 &ng_generic_typeinfo_type,
431 &ng_generic_list_getLength
432 };
433 static const struct ng_parse_type ng_generic_typeinfoarray_type = {
434 &ng_parse_array_type,
435 &ng_typeinfoarray_type_info
436 };
437
438 /* Array type for array of struct linkinfo in struct hooklist */
439 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = {
440 &ng_generic_linkinfo_type,
441 &ng_generic_linkinfo_getLength
442 };
443 static const struct ng_parse_type ng_generic_linkinfo_array_type = {
444 &ng_parse_array_type,
445 &ng_generic_linkinfo_array_type_info
446 };
447
448 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type));
449 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST,
450 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type));
451 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES,
452 (&ng_generic_nodeinfoarray_type));
453
454 /* List of commands and how to convert arguments to/from ASCII */
455 static const struct ng_cmdlist ng_generic_cmds[] = {
456 {
457 NGM_GENERIC_COOKIE,
458 NGM_SHUTDOWN,
459 "shutdown",
460 NULL,
461 NULL
462 },
463 {
464 NGM_GENERIC_COOKIE,
465 NGM_MKPEER,
466 "mkpeer",
467 &ng_generic_mkpeer_type,
468 NULL
469 },
470 {
471 NGM_GENERIC_COOKIE,
472 NGM_CONNECT,
473 "connect",
474 &ng_generic_connect_type,
475 NULL
476 },
477 {
478 NGM_GENERIC_COOKIE,
479 NGM_NAME,
480 "name",
481 &ng_generic_name_type,
482 NULL
483 },
484 {
485 NGM_GENERIC_COOKIE,
486 NGM_RMHOOK,
487 "rmhook",
488 &ng_generic_rmhook_type,
489 NULL
490 },
491 {
492 NGM_GENERIC_COOKIE,
493 NGM_NODEINFO,
494 "nodeinfo",
495 NULL,
496 &ng_generic_nodeinfo_type
497 },
498 {
499 NGM_GENERIC_COOKIE,
500 NGM_LISTHOOKS,
501 "listhooks",
502 NULL,
503 &ng_generic_hooklist_type
504 },
505 {
506 NGM_GENERIC_COOKIE,
507 NGM_LISTNAMES,
508 "listnames",
509 NULL,
510 &ng_generic_listnodes_type /* same as NGM_LISTNODES */
511 },
512 {
513 NGM_GENERIC_COOKIE,
514 NGM_LISTNODES,
515 "listnodes",
516 NULL,
517 &ng_generic_listnodes_type
518 },
519 {
520 NGM_GENERIC_COOKIE,
521 NGM_LISTTYPES,
522 "listtypes",
523 NULL,
524 &ng_generic_typeinfo_type
525 },
526 {
527 NGM_GENERIC_COOKIE,
528 NGM_TEXT_CONFIG,
529 "textconfig",
530 NULL,
531 &ng_parse_string_type
532 },
533 {
534 NGM_GENERIC_COOKIE,
535 NGM_TEXT_STATUS,
536 "textstatus",
537 NULL,
538 &ng_parse_string_type
539 },
540 {
541 NGM_GENERIC_COOKIE,
542 NGM_ASCII2BINARY,
543 "ascii2binary",
544 &ng_parse_ng_mesg_type,
545 &ng_parse_ng_mesg_type
546 },
547 {
548 NGM_GENERIC_COOKIE,
549 NGM_BINARY2ASCII,
550 "binary2ascii",
551 &ng_parse_ng_mesg_type,
552 &ng_parse_ng_mesg_type
553 },
554 { 0 }
555 };
556
557 /************************************************************************
558 Node routines
559 ************************************************************************/
560
561 /*
562 * Instantiate a node of the requested type
563 */
564 int
565 ng_make_node(const char *typename, node_p *nodepp)
566 {
567 struct ng_type *type;
568 int error;
569
570 /* Check that the type makes sense */
571 if (typename == NULL) {
572 TRAP_ERROR();
573 return (EINVAL);
574 }
575
576 /* Locate the node type. If we fail we return. Do not try to load
577 * module.
578 */
579 if ((type = ng_findtype(typename)) == NULL)
580 return (ENXIO);
581
582 /*
583 * If we have a constructor, then make the node and
584 * call the constructor to do type specific initialisation.
585 */
586 if (type->constructor != NULL) {
587 if ((error = ng_make_node_common(type, nodepp)) == 0) {
588 if ((error = ((*type->constructor)(*nodepp)) != 0)) {
589 NG_NODE_UNREF(*nodepp);
590 }
591 }
592 } else {
593 /*
594 * Node has no constructor. We cannot ask for one
595 * to be made. It must be brought into existence by
596 * some external agency. The external agency should
597 * call ng_make_node_common() directly to get the
598 * netgraph part initialised.
599 */
600 TRAP_ERROR();
601 error = EINVAL;
602 }
603 return (error);
604 }
605
606 /*
607 * Generic node creation. Called by node initialisation for externally
608 * instantiated nodes (e.g. hardware, sockets, etc ).
609 * The returned node has a reference count of 1.
610 */
611 int
612 ng_make_node_common(struct ng_type *type, node_p *nodepp)
613 {
614 node_p node;
615
616 /* Require the node type to have been already installed */
617 if (ng_findtype(type->name) == NULL) {
618 TRAP_ERROR();
619 return (EINVAL);
620 }
621
622 /* Make a node and try attach it to the type */
623 NG_ALLOC_NODE(node);
624 if (node == NULL) {
625 TRAP_ERROR();
626 return (ENOMEM);
627 }
628 node->nd_type = type;
629 NG_NODE_REF(node); /* note reference */
630 type->refs++;
631
632 NG_QUEUE_LOCK_INIT(&node->nd_input_queue);
633 STAILQ_INIT(&node->nd_input_queue.queue);
634 node->nd_input_queue.q_flags = 0;
635
636 /* Initialize hook list for new node */
637 LIST_INIT(&node->nd_hooks);
638
639 /* Link us into the name hash. */
640 mtx_lock(&ng_namehash_mtx);
641 LIST_INSERT_HEAD(&ng_name_hash[0], node, nd_nodes);
642 mtx_unlock(&ng_namehash_mtx);
643
644 /* get an ID and put us in the hash chain */
645 mtx_lock(&ng_idhash_mtx);
646 for (;;) { /* wrap protection, even if silly */
647 node_p node2 = NULL;
648 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */
649
650 /* Is there a problem with the new number? */
651 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */
652 if ((node->nd_ID != 0) && (node2 == NULL)) {
653 break;
654 }
655 }
656 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)],
657 node, nd_idnodes);
658 mtx_unlock(&ng_idhash_mtx);
659
660 /* Done */
661 *nodepp = node;
662 return (0);
663 }
664
665 /*
666 * Forceably start the shutdown process on a node. Either call
667 * its shutdown method, or do the default shutdown if there is
668 * no type-specific method.
669 *
670 * We can only be called from a shutdown message, so we know we have
671 * a writer lock, and therefore exclusive access. It also means
672 * that we should not be on the work queue, but we check anyhow.
673 *
674 * Persistent node types must have a type-specific method which
675 * allocates a new node in which case, this one is irretrievably going away,
676 * or cleans up anything it needs, and just makes the node valid again,
677 * in which case we allow the node to survive.
678 *
679 * XXX We need to think of how to tell a persistent node that we
680 * REALLY need to go away because the hardware has gone or we
681 * are rebooting.... etc.
682 */
683 void
684 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3)
685 {
686 hook_p hook;
687
688 /* Check if it's already shutting down */
689 if ((node->nd_flags & NGF_CLOSING) != 0)
690 return;
691
692 if (node == &ng_deadnode) {
693 printf ("shutdown called on deadnode\n");
694 return;
695 }
696
697 /* Add an extra reference so it doesn't go away during this */
698 NG_NODE_REF(node);
699
700 /*
701 * Mark it invalid so any newcomers know not to try use it
702 * Also add our own mark so we can't recurse
703 * note that NGF_INVALID does not do this as it's also set during
704 * creation
705 */
706 node->nd_flags |= NGF_INVALID|NGF_CLOSING;
707
708 /* If node has its pre-shutdown method, then call it first*/
709 if (node->nd_type && node->nd_type->close)
710 (*node->nd_type->close)(node);
711
712 /* Notify all remaining connected nodes to disconnect */
713 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL)
714 ng_destroy_hook(hook);
715
716 /*
717 * Drain the input queue forceably.
718 * it has no hooks so what's it going to do, bleed on someone?
719 * Theoretically we came here from a queue entry that was added
720 * Just before the queue was closed, so it should be empty anyway.
721 * Also removes us from worklist if needed.
722 */
723 ng_flush_input_queue(node);
724
725 /* Ask the type if it has anything to do in this case */
726 if (node->nd_type && node->nd_type->shutdown) {
727 (*node->nd_type->shutdown)(node);
728 if (NG_NODE_IS_VALID(node)) {
729 /*
730 * Well, blow me down if the node code hasn't declared
731 * that it doesn't want to die.
732 * Presumably it is a persistant node.
733 * If we REALLY want it to go away,
734 * e.g. hardware going away,
735 * Our caller should set NGF_REALLY_DIE in nd_flags.
736 */
737 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING);
738 NG_NODE_UNREF(node); /* Assume they still have theirs */
739 return;
740 }
741 } else { /* do the default thing */
742 NG_NODE_UNREF(node);
743 }
744
745 ng_unname(node); /* basically a NOP these days */
746
747 /*
748 * Remove extra reference, possibly the last
749 * Possible other holders of references may include
750 * timeout callouts, but theoretically the node's supposed to
751 * have cancelled them. Possibly hardware dependencies may
752 * force a driver to 'linger' with a reference.
753 */
754 NG_NODE_UNREF(node);
755 }
756
757 /*
758 * Remove a reference to the node, possibly the last.
759 * deadnode always acts as it it were the last.
760 */
761 int
762 ng_unref_node(node_p node)
763 {
764 int v;
765
766 if (node == &ng_deadnode) {
767 return (0);
768 }
769
770 v = atomic_fetchadd_int(&node->nd_refs, -1);
771
772 if (v == 1) { /* we were the last */
773
774 mtx_lock(&ng_namehash_mtx);
775 node->nd_type->refs--; /* XXX maybe should get types lock? */
776 LIST_REMOVE(node, nd_nodes);
777 mtx_unlock(&ng_namehash_mtx);
778
779 mtx_lock(&ng_idhash_mtx);
780 LIST_REMOVE(node, nd_idnodes);
781 mtx_unlock(&ng_idhash_mtx);
782
783 mtx_destroy(&node->nd_input_queue.q_mtx);
784 NG_FREE_NODE(node);
785 }
786 return (v - 1);
787 }
788
789 /************************************************************************
790 Node ID handling
791 ************************************************************************/
792 static node_p
793 ng_ID2noderef(ng_ID_t ID)
794 {
795 node_p node;
796 mtx_lock(&ng_idhash_mtx);
797 NG_IDHASH_FIND(ID, node);
798 if(node)
799 NG_NODE_REF(node);
800 mtx_unlock(&ng_idhash_mtx);
801 return(node);
802 }
803
804 ng_ID_t
805 ng_node2ID(node_p node)
806 {
807 return (node ? NG_NODE_ID(node) : 0);
808 }
809
810 /************************************************************************
811 Node name handling
812 ************************************************************************/
813
814 /*
815 * Assign a node a name. Once assigned, the name cannot be changed.
816 */
817 int
818 ng_name_node(node_p node, const char *name)
819 {
820 int i, hash;
821 node_p node2;
822
823 /* Check the name is valid */
824 for (i = 0; i < NG_NODESIZ; i++) {
825 if (name[i] == '\0' || name[i] == '.' || name[i] == ':')
826 break;
827 }
828 if (i == 0 || name[i] != '\0') {
829 TRAP_ERROR();
830 return (EINVAL);
831 }
832 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */
833 TRAP_ERROR();
834 return (EINVAL);
835 }
836
837 /* Check the name isn't already being used */
838 if ((node2 = ng_name2noderef(node, name)) != NULL) {
839 NG_NODE_UNREF(node2);
840 TRAP_ERROR();
841 return (EADDRINUSE);
842 }
843
844 /* copy it */
845 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ);
846
847 /* Update name hash. */
848 NG_NAMEHASH(name, hash);
849 mtx_lock(&ng_namehash_mtx);
850 LIST_REMOVE(node, nd_nodes);
851 LIST_INSERT_HEAD(&ng_name_hash[hash], node, nd_nodes);
852 mtx_unlock(&ng_namehash_mtx);
853
854 return (0);
855 }
856
857 /*
858 * Find a node by absolute name. The name should NOT end with ':'
859 * The name "." means "this node" and "[xxx]" means "the node
860 * with ID (ie, at address) xxx".
861 *
862 * Returns the node if found, else NULL.
863 * Eventually should add something faster than a sequential search.
864 * Note it acquires a reference on the node so you can be sure it's still
865 * there.
866 */
867 node_p
868 ng_name2noderef(node_p here, const char *name)
869 {
870 node_p node;
871 ng_ID_t temp;
872 int hash;
873
874 /* "." means "this node" */
875 if (strcmp(name, ".") == 0) {
876 NG_NODE_REF(here);
877 return(here);
878 }
879
880 /* Check for name-by-ID */
881 if ((temp = ng_decodeidname(name)) != 0) {
882 return (ng_ID2noderef(temp));
883 }
884
885 /* Find node by name */
886 NG_NAMEHASH(name, hash);
887 mtx_lock(&ng_namehash_mtx);
888 LIST_FOREACH(node, &ng_name_hash[hash], nd_nodes) {
889 if (NG_NODE_IS_VALID(node) &&
890 (strcmp(NG_NODE_NAME(node), name) == 0)) {
891 break;
892 }
893 }
894 if (node)
895 NG_NODE_REF(node);
896 mtx_unlock(&ng_namehash_mtx);
897 return (node);
898 }
899
900 /*
901 * Decode an ID name, eg. "[f03034de]". Returns 0 if the
902 * string is not valid, otherwise returns the value.
903 */
904 static ng_ID_t
905 ng_decodeidname(const char *name)
906 {
907 const int len = strlen(name);
908 char *eptr;
909 u_long val;
910
911 /* Check for proper length, brackets, no leading junk */
912 if ((len < 3)
913 || (name[0] != '[')
914 || (name[len - 1] != ']')
915 || (!isxdigit(name[1]))) {
916 return ((ng_ID_t)0);
917 }
918
919 /* Decode number */
920 val = strtoul(name + 1, &eptr, 16);
921 if ((eptr - name != len - 1)
922 || (val == ULONG_MAX)
923 || (val == 0)) {
924 return ((ng_ID_t)0);
925 }
926 return (ng_ID_t)val;
927 }
928
929 /*
930 * Remove a name from a node. This should only be called
931 * when shutting down and removing the node.
932 * IF we allow name changing this may be more resurrected.
933 */
934 void
935 ng_unname(node_p node)
936 {
937 }
938
939 /************************************************************************
940 Hook routines
941 Names are not optional. Hooks are always connected, except for a
942 brief moment within these routines. On invalidation or during creation
943 they are connected to the 'dead' hook.
944 ************************************************************************/
945
946 /*
947 * Remove a hook reference
948 */
949 void
950 ng_unref_hook(hook_p hook)
951 {
952 int v;
953
954 if (hook == &ng_deadhook) {
955 return;
956 }
957
958 v = atomic_fetchadd_int(&hook->hk_refs, -1);
959
960 if (v == 1) { /* we were the last */
961 if (_NG_HOOK_NODE(hook)) /* it'll probably be ng_deadnode */
962 _NG_NODE_UNREF((_NG_HOOK_NODE(hook)));
963 NG_FREE_HOOK(hook);
964 }
965 }
966
967 /*
968 * Add an unconnected hook to a node. Only used internally.
969 * Assumes node is locked. (XXX not yet true )
970 */
971 static int
972 ng_add_hook(node_p node, const char *name, hook_p *hookp)
973 {
974 hook_p hook;
975 int error = 0;
976
977 /* Check that the given name is good */
978 if (name == NULL) {
979 TRAP_ERROR();
980 return (EINVAL);
981 }
982 if (ng_findhook(node, name) != NULL) {
983 TRAP_ERROR();
984 return (EEXIST);
985 }
986
987 /* Allocate the hook and link it up */
988 NG_ALLOC_HOOK(hook);
989 if (hook == NULL) {
990 TRAP_ERROR();
991 return (ENOMEM);
992 }
993 hook->hk_refs = 1; /* add a reference for us to return */
994 hook->hk_flags = HK_INVALID;
995 hook->hk_peer = &ng_deadhook; /* start off this way */
996 hook->hk_node = node;
997 NG_NODE_REF(node); /* each hook counts as a reference */
998
999 /* Set hook name */
1000 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ);
1001
1002 /*
1003 * Check if the node type code has something to say about it
1004 * If it fails, the unref of the hook will also unref the node.
1005 */
1006 if (node->nd_type->newhook != NULL) {
1007 if ((error = (*node->nd_type->newhook)(node, hook, name))) {
1008 NG_HOOK_UNREF(hook); /* this frees the hook */
1009 return (error);
1010 }
1011 }
1012 /*
1013 * The 'type' agrees so far, so go ahead and link it in.
1014 * We'll ask again later when we actually connect the hooks.
1015 */
1016 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
1017 node->nd_numhooks++;
1018 NG_HOOK_REF(hook); /* one for the node */
1019
1020 if (hookp)
1021 *hookp = hook;
1022 return (0);
1023 }
1024
1025 /*
1026 * Find a hook
1027 *
1028 * Node types may supply their own optimized routines for finding
1029 * hooks. If none is supplied, we just do a linear search.
1030 * XXX Possibly we should add a reference to the hook?
1031 */
1032 hook_p
1033 ng_findhook(node_p node, const char *name)
1034 {
1035 hook_p hook;
1036
1037 if (node->nd_type->findhook != NULL)
1038 return (*node->nd_type->findhook)(node, name);
1039 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
1040 if (NG_HOOK_IS_VALID(hook)
1041 && (strcmp(NG_HOOK_NAME(hook), name) == 0))
1042 return (hook);
1043 }
1044 return (NULL);
1045 }
1046
1047 /*
1048 * Destroy a hook
1049 *
1050 * As hooks are always attached, this really destroys two hooks.
1051 * The one given, and the one attached to it. Disconnect the hooks
1052 * from each other first. We reconnect the peer hook to the 'dead'
1053 * hook so that it can still exist after we depart. We then
1054 * send the peer its own destroy message. This ensures that we only
1055 * interact with the peer's structures when it is locked processing that
1056 * message. We hold a reference to the peer hook so we are guaranteed that
1057 * the peer hook and node are still going to exist until
1058 * we are finished there as the hook holds a ref on the node.
1059 * We run this same code again on the peer hook, but that time it is already
1060 * attached to the 'dead' hook.
1061 *
1062 * This routine is called at all stages of hook creation
1063 * on error detection and must be able to handle any such stage.
1064 */
1065 void
1066 ng_destroy_hook(hook_p hook)
1067 {
1068 hook_p peer;
1069 node_p node;
1070
1071 if (hook == &ng_deadhook) { /* better safe than sorry */
1072 printf("ng_destroy_hook called on deadhook\n");
1073 return;
1074 }
1075
1076 /*
1077 * Protect divorce process with mutex, to avoid races on
1078 * simultaneous disconnect.
1079 */
1080 mtx_lock(&ng_topo_mtx);
1081
1082 hook->hk_flags |= HK_INVALID;
1083
1084 peer = NG_HOOK_PEER(hook);
1085 node = NG_HOOK_NODE(hook);
1086
1087 if (peer && (peer != &ng_deadhook)) {
1088 /*
1089 * Set the peer to point to ng_deadhook
1090 * from this moment on we are effectively independent it.
1091 * send it an rmhook message of it's own.
1092 */
1093 peer->hk_peer = &ng_deadhook; /* They no longer know us */
1094 hook->hk_peer = &ng_deadhook; /* Nor us, them */
1095 if (NG_HOOK_NODE(peer) == &ng_deadnode) {
1096 /*
1097 * If it's already divorced from a node,
1098 * just free it.
1099 */
1100 mtx_unlock(&ng_topo_mtx);
1101 } else {
1102 mtx_unlock(&ng_topo_mtx);
1103 ng_rmhook_self(peer); /* Send it a surprise */
1104 }
1105 NG_HOOK_UNREF(peer); /* account for peer link */
1106 NG_HOOK_UNREF(hook); /* account for peer link */
1107 } else
1108 mtx_unlock(&ng_topo_mtx);
1109
1110 mtx_assert(&ng_topo_mtx, MA_NOTOWNED);
1111
1112 /*
1113 * Remove the hook from the node's list to avoid possible recursion
1114 * in case the disconnection results in node shutdown.
1115 */
1116 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */
1117 return;
1118 }
1119 LIST_REMOVE(hook, hk_hooks);
1120 node->nd_numhooks--;
1121 if (node->nd_type->disconnect) {
1122 /*
1123 * The type handler may elect to destroy the node so don't
1124 * trust its existence after this point. (except
1125 * that we still hold a reference on it. (which we
1126 * inherrited from the hook we are destroying)
1127 */
1128 (*node->nd_type->disconnect) (hook);
1129 }
1130
1131 /*
1132 * Note that because we will point to ng_deadnode, the original node
1133 * is not decremented automatically so we do that manually.
1134 */
1135 _NG_HOOK_NODE(hook) = &ng_deadnode;
1136 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */
1137 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */
1138 }
1139
1140 /*
1141 * Take two hooks on a node and merge the connection so that the given node
1142 * is effectively bypassed.
1143 */
1144 int
1145 ng_bypass(hook_p hook1, hook_p hook2)
1146 {
1147 if (hook1->hk_node != hook2->hk_node) {
1148 TRAP_ERROR();
1149 return (EINVAL);
1150 }
1151 hook1->hk_peer->hk_peer = hook2->hk_peer;
1152 hook2->hk_peer->hk_peer = hook1->hk_peer;
1153
1154 hook1->hk_peer = &ng_deadhook;
1155 hook2->hk_peer = &ng_deadhook;
1156
1157 NG_HOOK_UNREF(hook1);
1158 NG_HOOK_UNREF(hook2);
1159
1160 /* XXX If we ever cache methods on hooks update them as well */
1161 ng_destroy_hook(hook1);
1162 ng_destroy_hook(hook2);
1163 return (0);
1164 }
1165
1166 /*
1167 * Install a new netgraph type
1168 */
1169 int
1170 ng_newtype(struct ng_type *tp)
1171 {
1172 const size_t namelen = strlen(tp->name);
1173
1174 /* Check version and type name fields */
1175 if ((tp->version != NG_ABI_VERSION)
1176 || (namelen == 0)
1177 || (namelen >= NG_TYPESIZ)) {
1178 TRAP_ERROR();
1179 if (tp->version != NG_ABI_VERSION) {
1180 printf("Netgraph: Node type rejected. ABI mismatch. Suggest recompile\n");
1181 }
1182 return (EINVAL);
1183 }
1184
1185 /* Check for name collision */
1186 if (ng_findtype(tp->name) != NULL) {
1187 TRAP_ERROR();
1188 return (EEXIST);
1189 }
1190
1191
1192 /* Link in new type */
1193 mtx_lock(&ng_typelist_mtx);
1194 LIST_INSERT_HEAD(&ng_typelist, tp, types);
1195 tp->refs = 1; /* first ref is linked list */
1196 mtx_unlock(&ng_typelist_mtx);
1197 return (0);
1198 }
1199
1200 /*
1201 * unlink a netgraph type
1202 * If no examples exist
1203 */
1204 int
1205 ng_rmtype(struct ng_type *tp)
1206 {
1207 /* Check for name collision */
1208 if (tp->refs != 1) {
1209 TRAP_ERROR();
1210 return (EBUSY);
1211 }
1212
1213 /* Unlink type */
1214 mtx_lock(&ng_typelist_mtx);
1215 LIST_REMOVE(tp, types);
1216 mtx_unlock(&ng_typelist_mtx);
1217 return (0);
1218 }
1219
1220 /*
1221 * Look for a type of the name given
1222 */
1223 struct ng_type *
1224 ng_findtype(const char *typename)
1225 {
1226 struct ng_type *type;
1227
1228 mtx_lock(&ng_typelist_mtx);
1229 LIST_FOREACH(type, &ng_typelist, types) {
1230 if (strcmp(type->name, typename) == 0)
1231 break;
1232 }
1233 mtx_unlock(&ng_typelist_mtx);
1234 return (type);
1235 }
1236
1237 /************************************************************************
1238 Composite routines
1239 ************************************************************************/
1240 /*
1241 * Connect two nodes using the specified hooks, using queued functions.
1242 */
1243 static int
1244 ng_con_part3(node_p node, item_p item, hook_p hook)
1245 {
1246 int error = 0;
1247
1248 /*
1249 * When we run, we know that the node 'node' is locked for us.
1250 * Our caller has a reference on the hook.
1251 * Our caller has a reference on the node.
1252 * (In this case our caller is ng_apply_item() ).
1253 * The peer hook has a reference on the hook.
1254 * We are all set up except for the final call to the node, and
1255 * the clearing of the INVALID flag.
1256 */
1257 if (NG_HOOK_NODE(hook) == &ng_deadnode) {
1258 /*
1259 * The node must have been freed again since we last visited
1260 * here. ng_destry_hook() has this effect but nothing else does.
1261 * We should just release our references and
1262 * free anything we can think of.
1263 * Since we know it's been destroyed, and it's our caller
1264 * that holds the references, just return.
1265 */
1266 ERROUT(ENOENT);
1267 }
1268 if (hook->hk_node->nd_type->connect) {
1269 if ((error = (*hook->hk_node->nd_type->connect) (hook))) {
1270 ng_destroy_hook(hook); /* also zaps peer */
1271 printf("failed in ng_con_part3()\n");
1272 ERROUT(error);
1273 }
1274 }
1275 /*
1276 * XXX this is wrong for SMP. Possibly we need
1277 * to separate out 'create' and 'invalid' flags.
1278 * should only set flags on hooks we have locked under our node.
1279 */
1280 hook->hk_flags &= ~HK_INVALID;
1281 done:
1282 NG_FREE_ITEM(item);
1283 return (error);
1284 }
1285
1286 static int
1287 ng_con_part2(node_p node, item_p item, hook_p hook)
1288 {
1289 hook_p peer;
1290 int error = 0;
1291
1292 /*
1293 * When we run, we know that the node 'node' is locked for us.
1294 * Our caller has a reference on the hook.
1295 * Our caller has a reference on the node.
1296 * (In this case our caller is ng_apply_item() ).
1297 * The peer hook has a reference on the hook.
1298 * our node pointer points to the 'dead' node.
1299 * First check the hook name is unique.
1300 * Should not happen because we checked before queueing this.
1301 */
1302 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) {
1303 TRAP_ERROR();
1304 ng_destroy_hook(hook); /* should destroy peer too */
1305 printf("failed in ng_con_part2()\n");
1306 ERROUT(EEXIST);
1307 }
1308 /*
1309 * Check if the node type code has something to say about it
1310 * If it fails, the unref of the hook will also unref the attached node,
1311 * however since that node is 'ng_deadnode' this will do nothing.
1312 * The peer hook will also be destroyed.
1313 */
1314 if (node->nd_type->newhook != NULL) {
1315 if ((error = (*node->nd_type->newhook)(node, hook,
1316 hook->hk_name))) {
1317 ng_destroy_hook(hook); /* should destroy peer too */
1318 printf("failed in ng_con_part2()\n");
1319 ERROUT(error);
1320 }
1321 }
1322
1323 /*
1324 * The 'type' agrees so far, so go ahead and link it in.
1325 * We'll ask again later when we actually connect the hooks.
1326 */
1327 hook->hk_node = node; /* just overwrite ng_deadnode */
1328 NG_NODE_REF(node); /* each hook counts as a reference */
1329 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
1330 node->nd_numhooks++;
1331 NG_HOOK_REF(hook); /* one for the node */
1332
1333 /*
1334 * We now have a symmetrical situation, where both hooks have been
1335 * linked to their nodes, the newhook methods have been called
1336 * And the references are all correct. The hooks are still marked
1337 * as invalid, as we have not called the 'connect' methods
1338 * yet.
1339 * We can call the local one immediately as we have the
1340 * node locked, but we need to queue the remote one.
1341 */
1342 if (hook->hk_node->nd_type->connect) {
1343 if ((error = (*hook->hk_node->nd_type->connect) (hook))) {
1344 ng_destroy_hook(hook); /* also zaps peer */
1345 printf("failed in ng_con_part2(A)\n");
1346 ERROUT(error);
1347 }
1348 }
1349
1350 /*
1351 * Acquire topo mutex to avoid race with ng_destroy_hook().
1352 */
1353 mtx_lock(&ng_topo_mtx);
1354 peer = hook->hk_peer;
1355 if (peer == &ng_deadhook) {
1356 mtx_unlock(&ng_topo_mtx);
1357 printf("failed in ng_con_part2(B)\n");
1358 ng_destroy_hook(hook);
1359 ERROUT(ENOENT);
1360 }
1361 mtx_unlock(&ng_topo_mtx);
1362
1363 if ((error = ng_send_fn2(peer->hk_node, peer, item, &ng_con_part3,
1364 NULL, 0, NG_REUSE_ITEM))) {
1365 printf("failed in ng_con_part2(C)\n");
1366 ng_destroy_hook(hook); /* also zaps peer */
1367 return (error); /* item was consumed. */
1368 }
1369 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */
1370 return (0); /* item was consumed. */
1371 done:
1372 NG_FREE_ITEM(item);
1373 return (error);
1374 }
1375
1376 /*
1377 * Connect this node with another node. We assume that this node is
1378 * currently locked, as we are only called from an NGM_CONNECT message.
1379 */
1380 static int
1381 ng_con_nodes(item_p item, node_p node, const char *name,
1382 node_p node2, const char *name2)
1383 {
1384 int error;
1385 hook_p hook;
1386 hook_p hook2;
1387
1388 if (ng_findhook(node2, name2) != NULL) {
1389 return(EEXIST);
1390 }
1391 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */
1392 return (error);
1393 /* Allocate the other hook and link it up */
1394 NG_ALLOC_HOOK(hook2);
1395 if (hook2 == NULL) {
1396 TRAP_ERROR();
1397 ng_destroy_hook(hook); /* XXX check ref counts so far */
1398 NG_HOOK_UNREF(hook); /* including our ref */
1399 return (ENOMEM);
1400 }
1401 hook2->hk_refs = 1; /* start with a reference for us. */
1402 hook2->hk_flags = HK_INVALID;
1403 hook2->hk_peer = hook; /* Link the two together */
1404 hook->hk_peer = hook2;
1405 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/
1406 NG_HOOK_REF(hook2);
1407 hook2->hk_node = &ng_deadnode;
1408 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ);
1409
1410 /*
1411 * Queue the function above.
1412 * Procesing continues in that function in the lock context of
1413 * the other node.
1414 */
1415 if ((error = ng_send_fn2(node2, hook2, item, &ng_con_part2, NULL, 0,
1416 NG_NOFLAGS))) {
1417 printf("failed in ng_con_nodes(): %d\n", error);
1418 ng_destroy_hook(hook); /* also zaps peer */
1419 }
1420
1421 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */
1422 NG_HOOK_UNREF(hook2);
1423 return (error);
1424 }
1425
1426 /*
1427 * Make a peer and connect.
1428 * We assume that the local node is locked.
1429 * The new node probably doesn't need a lock until
1430 * it has a hook, because it cannot really have any work until then,
1431 * but we should think about it a bit more.
1432 *
1433 * The problem may come if the other node also fires up
1434 * some hardware or a timer or some other source of activation,
1435 * also it may already get a command msg via it's ID.
1436 *
1437 * We could use the same method as ng_con_nodes() but we'd have
1438 * to add ability to remove the node when failing. (Not hard, just
1439 * make arg1 point to the node to remove).
1440 * Unless of course we just ignore failure to connect and leave
1441 * an unconnected node?
1442 */
1443 static int
1444 ng_mkpeer(node_p node, const char *name, const char *name2, char *type)
1445 {
1446 node_p node2;
1447 hook_p hook1, hook2;
1448 int error;
1449
1450 if ((error = ng_make_node(type, &node2))) {
1451 return (error);
1452 }
1453
1454 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */
1455 ng_rmnode(node2, NULL, NULL, 0);
1456 return (error);
1457 }
1458
1459 if ((error = ng_add_hook(node2, name2, &hook2))) {
1460 ng_rmnode(node2, NULL, NULL, 0);
1461 ng_destroy_hook(hook1);
1462 NG_HOOK_UNREF(hook1);
1463 return (error);
1464 }
1465
1466 /*
1467 * Actually link the two hooks together.
1468 */
1469 hook1->hk_peer = hook2;
1470 hook2->hk_peer = hook1;
1471
1472 /* Each hook is referenced by the other */
1473 NG_HOOK_REF(hook1);
1474 NG_HOOK_REF(hook2);
1475
1476 /* Give each node the opportunity to veto the pending connection */
1477 if (hook1->hk_node->nd_type->connect) {
1478 error = (*hook1->hk_node->nd_type->connect) (hook1);
1479 }
1480
1481 if ((error == 0) && hook2->hk_node->nd_type->connect) {
1482 error = (*hook2->hk_node->nd_type->connect) (hook2);
1483
1484 }
1485
1486 /*
1487 * drop the references we were holding on the two hooks.
1488 */
1489 if (error) {
1490 ng_destroy_hook(hook2); /* also zaps hook1 */
1491 ng_rmnode(node2, NULL, NULL, 0);
1492 } else {
1493 /* As a last act, allow the hooks to be used */
1494 hook1->hk_flags &= ~HK_INVALID;
1495 hook2->hk_flags &= ~HK_INVALID;
1496 }
1497 NG_HOOK_UNREF(hook1);
1498 NG_HOOK_UNREF(hook2);
1499 return (error);
1500 }
1501
1502 /************************************************************************
1503 Utility routines to send self messages
1504 ************************************************************************/
1505
1506 /* Shut this node down as soon as everyone is clear of it */
1507 /* Should add arg "immediately" to jump the queue */
1508 int
1509 ng_rmnode_self(node_p node)
1510 {
1511 int error;
1512
1513 if (node == &ng_deadnode)
1514 return (0);
1515 node->nd_flags |= NGF_INVALID;
1516 if (node->nd_flags & NGF_CLOSING)
1517 return (0);
1518
1519 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0);
1520 return (error);
1521 }
1522
1523 static void
1524 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2)
1525 {
1526 ng_destroy_hook(hook);
1527 return ;
1528 }
1529
1530 int
1531 ng_rmhook_self(hook_p hook)
1532 {
1533 int error;
1534 node_p node = NG_HOOK_NODE(hook);
1535
1536 if (node == &ng_deadnode)
1537 return (0);
1538
1539 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0);
1540 return (error);
1541 }
1542
1543 /***********************************************************************
1544 * Parse and verify a string of the form: <NODE:><PATH>
1545 *
1546 * Such a string can refer to a specific node or a specific hook
1547 * on a specific node, depending on how you look at it. In the
1548 * latter case, the PATH component must not end in a dot.
1549 *
1550 * Both <NODE:> and <PATH> are optional. The <PATH> is a string
1551 * of hook names separated by dots. This breaks out the original
1552 * string, setting *nodep to "NODE" (or NULL if none) and *pathp
1553 * to "PATH" (or NULL if degenerate). Also, *hookp will point to
1554 * the final hook component of <PATH>, if any, otherwise NULL.
1555 *
1556 * This returns -1 if the path is malformed. The char ** are optional.
1557 ***********************************************************************/
1558 int
1559 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp)
1560 {
1561 char *node, *path, *hook;
1562 int k;
1563
1564 /*
1565 * Extract absolute NODE, if any
1566 */
1567 for (path = addr; *path && *path != ':'; path++);
1568 if (*path) {
1569 node = addr; /* Here's the NODE */
1570 *path++ = '\0'; /* Here's the PATH */
1571
1572 /* Node name must not be empty */
1573 if (!*node)
1574 return -1;
1575
1576 /* A name of "." is OK; otherwise '.' not allowed */
1577 if (strcmp(node, ".") != 0) {
1578 for (k = 0; node[k]; k++)
1579 if (node[k] == '.')
1580 return -1;
1581 }
1582 } else {
1583 node = NULL; /* No absolute NODE */
1584 path = addr; /* Here's the PATH */
1585 }
1586
1587 /* Snoop for illegal characters in PATH */
1588 for (k = 0; path[k]; k++)
1589 if (path[k] == ':')
1590 return -1;
1591
1592 /* Check for no repeated dots in PATH */
1593 for (k = 0; path[k]; k++)
1594 if (path[k] == '.' && path[k + 1] == '.')
1595 return -1;
1596
1597 /* Remove extra (degenerate) dots from beginning or end of PATH */
1598 if (path[0] == '.')
1599 path++;
1600 if (*path && path[strlen(path) - 1] == '.')
1601 path[strlen(path) - 1] = 0;
1602
1603 /* If PATH has a dot, then we're not talking about a hook */
1604 if (*path) {
1605 for (hook = path, k = 0; path[k]; k++)
1606 if (path[k] == '.') {
1607 hook = NULL;
1608 break;
1609 }
1610 } else
1611 path = hook = NULL;
1612
1613 /* Done */
1614 if (nodep)
1615 *nodep = node;
1616 if (pathp)
1617 *pathp = path;
1618 if (hookp)
1619 *hookp = hook;
1620 return (0);
1621 }
1622
1623 /*
1624 * Given a path, which may be absolute or relative, and a starting node,
1625 * return the destination node.
1626 */
1627 int
1628 ng_path2noderef(node_p here, const char *address,
1629 node_p *destp, hook_p *lasthook)
1630 {
1631 char fullpath[NG_PATHSIZ];
1632 char *nodename, *path, pbuf[2];
1633 node_p node, oldnode;
1634 char *cp;
1635 hook_p hook = NULL;
1636
1637 /* Initialize */
1638 if (destp == NULL) {
1639 TRAP_ERROR();
1640 return EINVAL;
1641 }
1642 *destp = NULL;
1643
1644 /* Make a writable copy of address for ng_path_parse() */
1645 strncpy(fullpath, address, sizeof(fullpath) - 1);
1646 fullpath[sizeof(fullpath) - 1] = '\0';
1647
1648 /* Parse out node and sequence of hooks */
1649 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) {
1650 TRAP_ERROR();
1651 return EINVAL;
1652 }
1653 if (path == NULL) {
1654 pbuf[0] = '.'; /* Needs to be writable */
1655 pbuf[1] = '\0';
1656 path = pbuf;
1657 }
1658
1659 /*
1660 * For an absolute address, jump to the starting node.
1661 * Note that this holds a reference on the node for us.
1662 * Don't forget to drop the reference if we don't need it.
1663 */
1664 if (nodename) {
1665 node = ng_name2noderef(here, nodename);
1666 if (node == NULL) {
1667 TRAP_ERROR();
1668 return (ENOENT);
1669 }
1670 } else {
1671 if (here == NULL) {
1672 TRAP_ERROR();
1673 return (EINVAL);
1674 }
1675 node = here;
1676 NG_NODE_REF(node);
1677 }
1678
1679 /*
1680 * Now follow the sequence of hooks
1681 * XXX
1682 * We actually cannot guarantee that the sequence
1683 * is not being demolished as we crawl along it
1684 * without extra-ordinary locking etc.
1685 * So this is a bit dodgy to say the least.
1686 * We can probably hold up some things by holding
1687 * the nodelist mutex for the time of this
1688 * crawl if we wanted.. At least that way we wouldn't have to
1689 * worry about the nodes disappearing, but the hooks would still
1690 * be a problem.
1691 */
1692 for (cp = path; node != NULL && *cp != '\0'; ) {
1693 char *segment;
1694
1695 /*
1696 * Break out the next path segment. Replace the dot we just
1697 * found with a NUL; "cp" points to the next segment (or the
1698 * NUL at the end).
1699 */
1700 for (segment = cp; *cp != '\0'; cp++) {
1701 if (*cp == '.') {
1702 *cp++ = '\0';
1703 break;
1704 }
1705 }
1706
1707 /* Empty segment */
1708 if (*segment == '\0')
1709 continue;
1710
1711 /* We have a segment, so look for a hook by that name */
1712 hook = ng_findhook(node, segment);
1713
1714 /* Can't get there from here... */
1715 if (hook == NULL
1716 || NG_HOOK_PEER(hook) == NULL
1717 || NG_HOOK_NOT_VALID(hook)
1718 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) {
1719 TRAP_ERROR();
1720 NG_NODE_UNREF(node);
1721 #if 0
1722 printf("hooknotvalid %s %s %d %d %d %d ",
1723 path,
1724 segment,
1725 hook == NULL,
1726 NG_HOOK_PEER(hook) == NULL,
1727 NG_HOOK_NOT_VALID(hook),
1728 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)));
1729 #endif
1730 return (ENOENT);
1731 }
1732
1733 /*
1734 * Hop on over to the next node
1735 * XXX
1736 * Big race conditions here as hooks and nodes go away
1737 * *** Idea.. store an ng_ID_t in each hook and use that
1738 * instead of the direct hook in this crawl?
1739 */
1740 oldnode = node;
1741 if ((node = NG_PEER_NODE(hook)))
1742 NG_NODE_REF(node); /* XXX RACE */
1743 NG_NODE_UNREF(oldnode); /* XXX another race */
1744 if (NG_NODE_NOT_VALID(node)) {
1745 NG_NODE_UNREF(node); /* XXX more races */
1746 node = NULL;
1747 }
1748 }
1749
1750 /* If node somehow missing, fail here (probably this is not needed) */
1751 if (node == NULL) {
1752 TRAP_ERROR();
1753 return (ENXIO);
1754 }
1755
1756 /* Done */
1757 *destp = node;
1758 if (lasthook != NULL)
1759 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL);
1760 return (0);
1761 }
1762
1763 /***************************************************************\
1764 * Input queue handling.
1765 * All activities are submitted to the node via the input queue
1766 * which implements a multiple-reader/single-writer gate.
1767 * Items which cannot be handled immediately are queued.
1768 *
1769 * read-write queue locking inline functions *
1770 \***************************************************************/
1771
1772 static __inline void ng_queue_rw(node_p node, item_p item, int rw);
1773 static __inline item_p ng_dequeue(node_p node, int *rw);
1774 static __inline item_p ng_acquire_read(node_p node, item_p item);
1775 static __inline item_p ng_acquire_write(node_p node, item_p item);
1776 static __inline void ng_leave_read(node_p node);
1777 static __inline void ng_leave_write(node_p node);
1778
1779 /*
1780 * Definition of the bits fields in the ng_queue flag word.
1781 * Defined here rather than in netgraph.h because no-one should fiddle
1782 * with them.
1783 *
1784 * The ordering here may be important! don't shuffle these.
1785 */
1786 /*-
1787 Safety Barrier--------+ (adjustable to suit taste) (not used yet)
1788 |
1789 V
1790 +-------+-------+-------+-------+-------+-------+-------+-------+
1791 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
1792 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |P|A|
1793 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |O|W|
1794 +-------+-------+-------+-------+-------+-------+-------+-------+
1795 \___________________________ ____________________________/ | |
1796 V | |
1797 [active reader count] | |
1798 | |
1799 Operation Pending -------------------------------+ |
1800 |
1801 Active Writer ---------------------------------------+
1802
1803 Node queue has such semantics:
1804 - All flags modifications are atomic.
1805 - Reader count can be incremented only if there is no writer or pending flags.
1806 As soon as this can't be done with single operation, it is implemented with
1807 spin loop and atomic_cmpset().
1808 - Writer flag can be set only if there is no any bits set.
1809 It is implemented with atomic_cmpset().
1810 - Pending flag can be set any time, but to avoid collision on queue processing
1811 all queue fields are protected by the mutex.
1812 - Queue processing thread reads queue holding the mutex, but releases it while
1813 processing. When queue is empty pending flag is removed.
1814 */
1815
1816 #define WRITER_ACTIVE 0x00000001
1817 #define OP_PENDING 0x00000002
1818 #define READER_INCREMENT 0x00000004
1819 #define READER_MASK 0xfffffffc /* Not valid if WRITER_ACTIVE is set */
1820 #define SAFETY_BARRIER 0x00100000 /* 128K items queued should be enough */
1821
1822 /* Defines of more elaborate states on the queue */
1823 /* Mask of bits a new read cares about */
1824 #define NGQ_RMASK (WRITER_ACTIVE|OP_PENDING)
1825
1826 /* Mask of bits a new write cares about */
1827 #define NGQ_WMASK (NGQ_RMASK|READER_MASK)
1828
1829 /* Test to decide if there is something on the queue. */
1830 #define QUEUE_ACTIVE(QP) ((QP)->q_flags & OP_PENDING)
1831
1832 /* How to decide what the next queued item is. */
1833 #define HEAD_IS_READER(QP) NGI_QUEUED_READER(STAILQ_FIRST(&(QP)->queue))
1834 #define HEAD_IS_WRITER(QP) NGI_QUEUED_WRITER(STAILQ_FIRST(&(QP)->queue)) /* notused */
1835
1836 /* Read the status to decide if the next item on the queue can now run. */
1837 #define QUEUED_READER_CAN_PROCEED(QP) \
1838 (((QP)->q_flags & (NGQ_RMASK & ~OP_PENDING)) == 0)
1839 #define QUEUED_WRITER_CAN_PROCEED(QP) \
1840 (((QP)->q_flags & (NGQ_WMASK & ~OP_PENDING)) == 0)
1841
1842 /* Is there a chance of getting ANY work off the queue? */
1843 #define NEXT_QUEUED_ITEM_CAN_PROCEED(QP) \
1844 ((HEAD_IS_READER(QP)) ? QUEUED_READER_CAN_PROCEED(QP) : \
1845 QUEUED_WRITER_CAN_PROCEED(QP))
1846
1847 #define NGQRW_R 0
1848 #define NGQRW_W 1
1849
1850 #define NGQ2_WORKQ 0x00000001
1851
1852 /*
1853 * Taking into account the current state of the queue and node, possibly take
1854 * the next entry off the queue and return it. Return NULL if there was
1855 * nothing we could return, either because there really was nothing there, or
1856 * because the node was in a state where it cannot yet process the next item
1857 * on the queue.
1858 */
1859 static __inline item_p
1860 ng_dequeue(node_p node, int *rw)
1861 {
1862 item_p item;
1863 struct ng_queue *ngq = &node->nd_input_queue;
1864
1865 /* This MUST be called with the mutex held. */
1866 mtx_assert(&ngq->q_mtx, MA_OWNED);
1867
1868 /* If there is nothing queued, then just return. */
1869 if (!QUEUE_ACTIVE(ngq)) {
1870 CTR4(KTR_NET, "%20s: node [%x] (%p) queue empty; "
1871 "queue flags 0x%lx", __func__,
1872 node->nd_ID, node, ngq->q_flags);
1873 return (NULL);
1874 }
1875
1876 /*
1877 * From here, we can assume there is a head item.
1878 * We need to find out what it is and if it can be dequeued, given
1879 * the current state of the node.
1880 */
1881 if (HEAD_IS_READER(ngq)) {
1882 while (1) {
1883 long t = ngq->q_flags;
1884 if (t & WRITER_ACTIVE) {
1885 /* There is writer, reader can't proceed. */
1886 CTR4(KTR_NET, "%20s: node [%x] (%p) queued reader "
1887 "can't proceed; queue flags 0x%lx", __func__,
1888 node->nd_ID, node, t);
1889 return (NULL);
1890 }
1891 if (atomic_cmpset_acq_int(&ngq->q_flags, t,
1892 t + READER_INCREMENT))
1893 break;
1894 cpu_spinwait();
1895 }
1896 /* We have got reader lock for the node. */
1897 *rw = NGQRW_R;
1898 } else if (atomic_cmpset_acq_int(&ngq->q_flags, OP_PENDING,
1899 OP_PENDING + WRITER_ACTIVE)) {
1900 /* We have got writer lock for the node. */
1901 *rw = NGQRW_W;
1902 } else {
1903 /* There is somebody other, writer can't proceed. */
1904 CTR4(KTR_NET, "%20s: node [%x] (%p) queued writer "
1905 "can't proceed; queue flags 0x%lx", __func__,
1906 node->nd_ID, node, ngq->q_flags);
1907 return (NULL);
1908 }
1909
1910 /*
1911 * Now we dequeue the request (whatever it may be) and correct the
1912 * pending flags and the next and last pointers.
1913 */
1914 item = STAILQ_FIRST(&ngq->queue);
1915 STAILQ_REMOVE_HEAD(&ngq->queue, el_next);
1916 if (STAILQ_EMPTY(&ngq->queue))
1917 atomic_clear_int(&ngq->q_flags, OP_PENDING);
1918 CTR6(KTR_NET, "%20s: node [%x] (%p) returning item %p as %s; "
1919 "queue flags 0x%lx", __func__,
1920 node->nd_ID, node, item, *rw ? "WRITER" : "READER" ,
1921 ngq->q_flags);
1922 return (item);
1923 }
1924
1925 /*
1926 * Queue a packet to be picked up later by someone else.
1927 * If the queue could be run now, add node to the queue handler's worklist.
1928 */
1929 static __inline void
1930 ng_queue_rw(node_p node, item_p item, int rw)
1931 {
1932 struct ng_queue *ngq = &node->nd_input_queue;
1933 if (rw == NGQRW_W)
1934 NGI_SET_WRITER(item);
1935 else
1936 NGI_SET_READER(item);
1937
1938 NG_QUEUE_LOCK(ngq);
1939 /* Set OP_PENDING flag and enqueue the item. */
1940 atomic_set_int(&ngq->q_flags, OP_PENDING);
1941 STAILQ_INSERT_TAIL(&ngq->queue, item, el_next);
1942
1943 CTR5(KTR_NET, "%20s: node [%x] (%p) queued item %p as %s", __func__,
1944 node->nd_ID, node, item, rw ? "WRITER" : "READER" );
1945
1946 /*
1947 * We can take the worklist lock with the node locked
1948 * BUT NOT THE REVERSE!
1949 */
1950 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
1951 ng_worklist_add(node);
1952 NG_QUEUE_UNLOCK(ngq);
1953 }
1954
1955 /* Acquire reader lock on node. If node is busy, queue the packet. */
1956 static __inline item_p
1957 ng_acquire_read(node_p node, item_p item)
1958 {
1959 KASSERT(node != &ng_deadnode,
1960 ("%s: working on deadnode", __func__));
1961
1962 /* Reader needs node without writer and pending items. */
1963 while (1) {
1964 long t = node->nd_input_queue.q_flags;
1965 if (t & NGQ_RMASK)
1966 break; /* Node is not ready for reader. */
1967 if (atomic_cmpset_acq_int(&node->nd_input_queue.q_flags,
1968 t, t + READER_INCREMENT)) {
1969 /* Successfully grabbed node */
1970 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p",
1971 __func__, node->nd_ID, node, item);
1972 return (item);
1973 }
1974 cpu_spinwait();
1975 };
1976
1977 /* Queue the request for later. */
1978 ng_queue_rw(node, item, NGQRW_R);
1979
1980 return (NULL);
1981 }
1982
1983 /* Acquire writer lock on node. If node is busy, queue the packet. */
1984 static __inline item_p
1985 ng_acquire_write(node_p node, item_p item)
1986 {
1987 KASSERT(node != &ng_deadnode,
1988 ("%s: working on deadnode", __func__));
1989
1990 /* Writer needs completely idle node. */
1991 if (atomic_cmpset_acq_int(&node->nd_input_queue.q_flags,
1992 0, WRITER_ACTIVE)) {
1993 /* Successfully grabbed node */
1994 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p",
1995 __func__, node->nd_ID, node, item);
1996 return (item);
1997 }
1998
1999 /* Queue the request for later. */
2000 ng_queue_rw(node, item, NGQRW_W);
2001
2002 return (NULL);
2003 }
2004
2005 #if 0
2006 static __inline item_p
2007 ng_upgrade_write(node_p node, item_p item)
2008 {
2009 struct ng_queue *ngq = &node->nd_input_queue;
2010 KASSERT(node != &ng_deadnode,
2011 ("%s: working on deadnode", __func__));
2012
2013 NGI_SET_WRITER(item);
2014
2015 NG_QUEUE_LOCK(ngq);
2016
2017 /*
2018 * There will never be no readers as we are there ourselves.
2019 * Set the WRITER_ACTIVE flags ASAP to block out fast track readers.
2020 * The caller we are running from will call ng_leave_read()
2021 * soon, so we must account for that. We must leave again with the
2022 * READER lock. If we find other readers, then
2023 * queue the request for later. However "later" may be rignt now
2024 * if there are no readers. We don't really care if there are queued
2025 * items as we will bypass them anyhow.
2026 */
2027 atomic_add_int(&ngq->q_flags, WRITER_ACTIVE - READER_INCREMENT);
2028 if ((ngq->q_flags & (NGQ_WMASK & ~OP_PENDING)) == WRITER_ACTIVE) {
2029 NG_QUEUE_UNLOCK(ngq);
2030
2031 /* It's just us, act on the item. */
2032 /* will NOT drop writer lock when done */
2033 ng_apply_item(node, item, 0);
2034
2035 /*
2036 * Having acted on the item, atomically
2037 * down grade back to READER and finish up
2038 */
2039 atomic_add_int(&ngq->q_flags,
2040 READER_INCREMENT - WRITER_ACTIVE);
2041
2042 /* Our caller will call ng_leave_read() */
2043 return;
2044 }
2045 /*
2046 * It's not just us active, so queue us AT THE HEAD.
2047 * "Why?" I hear you ask.
2048 * Put us at the head of the queue as we've already been
2049 * through it once. If there is nothing else waiting,
2050 * set the correct flags.
2051 */
2052 if (STAILQ_EMPTY(&ngq->queue)) {
2053 /* We've gone from, 0 to 1 item in the queue */
2054 atomic_set_int(&ngq->q_flags, OP_PENDING);
2055
2056 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__,
2057 node->nd_ID, node);
2058 };
2059 STAILQ_INSERT_HEAD(&ngq->queue, item, el_next);
2060 CTR4(KTR_NET, "%20s: node [%x] (%p) requeued item %p as WRITER",
2061 __func__, node->nd_ID, node, item );
2062
2063 /* Reverse what we did above. That downgrades us back to reader */
2064 atomic_add_int(&ngq->q_flags, READER_INCREMENT - WRITER_ACTIVE);
2065 if (QUEUE_ACTIVE(ngq) && NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2066 ng_worklist_add(node);
2067 NG_QUEUE_UNLOCK(ngq);
2068
2069 return;
2070 }
2071 #endif
2072
2073 /* Release reader lock. */
2074 static __inline void
2075 ng_leave_read(node_p node)
2076 {
2077 atomic_subtract_rel_int(&node->nd_input_queue.q_flags, READER_INCREMENT);
2078 }
2079
2080 /* Release writer lock. */
2081 static __inline void
2082 ng_leave_write(node_p node)
2083 {
2084 atomic_clear_rel_int(&node->nd_input_queue.q_flags, WRITER_ACTIVE);
2085 }
2086
2087 /* Purge node queue. Called on node shutdown. */
2088 static void
2089 ng_flush_input_queue(node_p node)
2090 {
2091 struct ng_queue *ngq = &node->nd_input_queue;
2092 item_p item;
2093
2094 NG_QUEUE_LOCK(ngq);
2095 while ((item = STAILQ_FIRST(&ngq->queue)) != NULL) {
2096 STAILQ_REMOVE_HEAD(&ngq->queue, el_next);
2097 if (STAILQ_EMPTY(&ngq->queue))
2098 atomic_clear_int(&ngq->q_flags, OP_PENDING);
2099 NG_QUEUE_UNLOCK(ngq);
2100
2101 /* If the item is supplying a callback, call it with an error */
2102 if (item->apply != NULL) {
2103 if (item->depth == 1)
2104 item->apply->error = ENOENT;
2105 if (refcount_release(&item->apply->refs)) {
2106 (*item->apply->apply)(item->apply->context,
2107 item->apply->error);
2108 }
2109 }
2110 NG_FREE_ITEM(item);
2111 NG_QUEUE_LOCK(ngq);
2112 }
2113 NG_QUEUE_UNLOCK(ngq);
2114 }
2115
2116 /***********************************************************************
2117 * Externally visible method for sending or queueing messages or data.
2118 ***********************************************************************/
2119
2120 /*
2121 * The module code should have filled out the item correctly by this stage:
2122 * Common:
2123 * reference to destination node.
2124 * Reference to destination rcv hook if relevant.
2125 * apply pointer must be or NULL or reference valid struct ng_apply_info.
2126 * Data:
2127 * pointer to mbuf
2128 * Control_Message:
2129 * pointer to msg.
2130 * ID of original sender node. (return address)
2131 * Function:
2132 * Function pointer
2133 * void * argument
2134 * integer argument
2135 *
2136 * The nodes have several routines and macros to help with this task:
2137 */
2138
2139 int
2140 ng_snd_item(item_p item, int flags)
2141 {
2142 hook_p hook;
2143 node_p node;
2144 int queue, rw;
2145 struct ng_queue *ngq;
2146 int error = 0;
2147
2148 /* We are sending item, so it must be present! */
2149 KASSERT(item != NULL, ("ng_snd_item: item is NULL"));
2150
2151 #ifdef NETGRAPH_DEBUG
2152 _ngi_check(item, __FILE__, __LINE__);
2153 #endif
2154
2155 /* Item was sent once more, postpone apply() call. */
2156 if (item->apply)
2157 refcount_acquire(&item->apply->refs);
2158
2159 node = NGI_NODE(item);
2160 /* Node is never optional. */
2161 KASSERT(node != NULL, ("ng_snd_item: node is NULL"));
2162
2163 hook = NGI_HOOK(item);
2164 /* Valid hook and mbuf are mandatory for data. */
2165 if ((item->el_flags & NGQF_TYPE) == NGQF_DATA) {
2166 KASSERT(hook != NULL, ("ng_snd_item: hook for data is NULL"));
2167 if (NGI_M(item) == NULL)
2168 ERROUT(EINVAL);
2169 CHECK_DATA_MBUF(NGI_M(item));
2170 }
2171
2172 /*
2173 * If the item or the node specifies single threading, force
2174 * writer semantics. Similarly, the node may say one hook always
2175 * produces writers. These are overrides.
2176 */
2177 if (((item->el_flags & NGQF_RW) == NGQF_WRITER) ||
2178 (node->nd_flags & NGF_FORCE_WRITER) ||
2179 (hook && (hook->hk_flags & HK_FORCE_WRITER))) {
2180 rw = NGQRW_W;
2181 } else {
2182 rw = NGQRW_R;
2183 }
2184
2185 /*
2186 * If sender or receiver requests queued delivery or stack usage
2187 * level is dangerous - enqueue message.
2188 */
2189 if ((flags & NG_QUEUE) || (hook && (hook->hk_flags & HK_QUEUE))) {
2190 queue = 1;
2191 } else {
2192 queue = 0;
2193 #ifdef GET_STACK_USAGE
2194 /*
2195 * Most of netgraph nodes have small stack consumption and
2196 * for them 25% of free stack space is more than enough.
2197 * Nodes/hooks with higher stack usage should be marked as
2198 * HI_STACK. For them 50% of stack will be guaranteed then.
2199 * XXX: Values 25% and 50% are completely empirical.
2200 */
2201 size_t st, su, sl;
2202 GET_STACK_USAGE(st, su);
2203 sl = st - su;
2204 if ((sl * 4 < st) ||
2205 ((sl * 2 < st) && ((node->nd_flags & NGF_HI_STACK) ||
2206 (hook && (hook->hk_flags & HK_HI_STACK))))) {
2207 queue = 1;
2208 }
2209 #endif
2210 }
2211
2212 if (queue) {
2213 item->depth = 1;
2214 /* Put it on the queue for that node*/
2215 ng_queue_rw(node, item, rw);
2216 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0);
2217 }
2218
2219 /*
2220 * We already decided how we will be queueud or treated.
2221 * Try get the appropriate operating permission.
2222 */
2223 if (rw == NGQRW_R)
2224 item = ng_acquire_read(node, item);
2225 else
2226 item = ng_acquire_write(node, item);
2227
2228 /* Item was queued while trying to get permission. */
2229 if (item == NULL)
2230 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0);
2231
2232 NGI_GET_NODE(item, node); /* zaps stored node */
2233
2234 item->depth++;
2235 error = ng_apply_item(node, item, rw); /* drops r/w lock when done */
2236
2237 /* If something is waiting on queue and ready, schedule it. */
2238 ngq = &node->nd_input_queue;
2239 if (QUEUE_ACTIVE(ngq)) {
2240 NG_QUEUE_LOCK(ngq);
2241 if (QUEUE_ACTIVE(ngq) && NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2242 ng_worklist_add(node);
2243 NG_QUEUE_UNLOCK(ngq);
2244 }
2245
2246 /*
2247 * Node may go away as soon as we remove the reference.
2248 * Whatever we do, DO NOT access the node again!
2249 */
2250 NG_NODE_UNREF(node);
2251
2252 return (error);
2253
2254 done:
2255 /* If was not sent, apply callback here. */
2256 if (item->apply != NULL) {
2257 if (item->depth == 0 && error != 0)
2258 item->apply->error = error;
2259 if (refcount_release(&item->apply->refs)) {
2260 (*item->apply->apply)(item->apply->context,
2261 item->apply->error);
2262 }
2263 }
2264
2265 NG_FREE_ITEM(item);
2266 return (error);
2267 }
2268
2269 /*
2270 * We have an item that was possibly queued somewhere.
2271 * It should contain all the information needed
2272 * to run it on the appropriate node/hook.
2273 * If there is apply pointer and we own the last reference, call apply().
2274 */
2275 static int
2276 ng_apply_item(node_p node, item_p item, int rw)
2277 {
2278 hook_p hook;
2279 ng_rcvdata_t *rcvdata;
2280 ng_rcvmsg_t *rcvmsg;
2281 struct ng_apply_info *apply;
2282 int error = 0, depth;
2283
2284 /* Node and item are never optional. */
2285 KASSERT(node != NULL, ("ng_apply_item: node is NULL"));
2286 KASSERT(item != NULL, ("ng_apply_item: item is NULL"));
2287
2288 NGI_GET_HOOK(item, hook); /* clears stored hook */
2289 #ifdef NETGRAPH_DEBUG
2290 _ngi_check(item, __FILE__, __LINE__);
2291 #endif
2292
2293 apply = item->apply;
2294 depth = item->depth;
2295
2296 switch (item->el_flags & NGQF_TYPE) {
2297 case NGQF_DATA:
2298 /*
2299 * Check things are still ok as when we were queued.
2300 */
2301 KASSERT(hook != NULL, ("ng_apply_item: hook for data is NULL"));
2302 if (NG_HOOK_NOT_VALID(hook) ||
2303 NG_NODE_NOT_VALID(node)) {
2304 error = EIO;
2305 NG_FREE_ITEM(item);
2306 break;
2307 }
2308 /*
2309 * If no receive method, just silently drop it.
2310 * Give preference to the hook over-ride method
2311 */
2312 if ((!(rcvdata = hook->hk_rcvdata))
2313 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) {
2314 error = 0;
2315 NG_FREE_ITEM(item);
2316 break;
2317 }
2318 error = (*rcvdata)(hook, item);
2319 break;
2320 case NGQF_MESG:
2321 if (hook && NG_HOOK_NOT_VALID(hook)) {
2322 /*
2323 * The hook has been zapped then we can't use it.
2324 * Immediately drop its reference.
2325 * The message may not need it.
2326 */
2327 NG_HOOK_UNREF(hook);
2328 hook = NULL;
2329 }
2330 /*
2331 * Similarly, if the node is a zombie there is
2332 * nothing we can do with it, drop everything.
2333 */
2334 if (NG_NODE_NOT_VALID(node)) {
2335 TRAP_ERROR();
2336 error = EINVAL;
2337 NG_FREE_ITEM(item);
2338 break;
2339 }
2340 /*
2341 * Call the appropriate message handler for the object.
2342 * It is up to the message handler to free the message.
2343 * If it's a generic message, handle it generically,
2344 * otherwise call the type's message handler (if it exists).
2345 * XXX (race). Remember that a queued message may
2346 * reference a node or hook that has just been
2347 * invalidated. It will exist as the queue code
2348 * is holding a reference, but..
2349 */
2350 if ((NGI_MSG(item)->header.typecookie == NGM_GENERIC_COOKIE) &&
2351 ((NGI_MSG(item)->header.flags & NGF_RESP) == 0)) {
2352 error = ng_generic_msg(node, item, hook);
2353 break;
2354 }
2355 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) &&
2356 (!(rcvmsg = node->nd_type->rcvmsg))) {
2357 TRAP_ERROR();
2358 error = 0;
2359 NG_FREE_ITEM(item);
2360 break;
2361 }
2362 error = (*rcvmsg)(node, item, hook);
2363 break;
2364 case NGQF_FN:
2365 case NGQF_FN2:
2366 /*
2367 * We have to implicitly trust the hook,
2368 * as some of these are used for system purposes
2369 * where the hook is invalid. In the case of
2370 * the shutdown message we allow it to hit
2371 * even if the node is invalid.
2372 */
2373 if ((NG_NODE_NOT_VALID(node))
2374 && (NGI_FN(item) != &ng_rmnode)) {
2375 TRAP_ERROR();
2376 error = EINVAL;
2377 NG_FREE_ITEM(item);
2378 break;
2379 }
2380 if ((item->el_flags & NGQF_TYPE) == NGQF_FN) {
2381 (*NGI_FN(item))(node, hook, NGI_ARG1(item),
2382 NGI_ARG2(item));
2383 NG_FREE_ITEM(item);
2384 } else /* it is NGQF_FN2 */
2385 error = (*NGI_FN2(item))(node, item, hook);
2386 break;
2387 }
2388 /*
2389 * We held references on some of the resources
2390 * that we took from the item. Now that we have
2391 * finished doing everything, drop those references.
2392 */
2393 if (hook)
2394 NG_HOOK_UNREF(hook);
2395
2396 if (rw == NGQRW_R)
2397 ng_leave_read(node);
2398 else
2399 ng_leave_write(node);
2400
2401 /* Apply callback. */
2402 if (apply != NULL) {
2403 if (depth == 1 && error != 0)
2404 apply->error = error;
2405 if (refcount_release(&apply->refs))
2406 (*apply->apply)(apply->context, apply->error);
2407 }
2408
2409 return (error);
2410 }
2411
2412 /***********************************************************************
2413 * Implement the 'generic' control messages
2414 ***********************************************************************/
2415 static int
2416 ng_generic_msg(node_p here, item_p item, hook_p lasthook)
2417 {
2418 int error = 0;
2419 struct ng_mesg *msg;
2420 struct ng_mesg *resp = NULL;
2421
2422 NGI_GET_MSG(item, msg);
2423 if (msg->header.typecookie != NGM_GENERIC_COOKIE) {
2424 TRAP_ERROR();
2425 error = EINVAL;
2426 goto out;
2427 }
2428 switch (msg->header.cmd) {
2429 case NGM_SHUTDOWN:
2430 ng_rmnode(here, NULL, NULL, 0);
2431 break;
2432 case NGM_MKPEER:
2433 {
2434 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data;
2435
2436 if (msg->header.arglen != sizeof(*mkp)) {
2437 TRAP_ERROR();
2438 error = EINVAL;
2439 break;
2440 }
2441 mkp->type[sizeof(mkp->type) - 1] = '\0';
2442 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0';
2443 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0';
2444 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type);
2445 break;
2446 }
2447 case NGM_CONNECT:
2448 {
2449 struct ngm_connect *const con =
2450 (struct ngm_connect *) msg->data;
2451 node_p node2;
2452
2453 if (msg->header.arglen != sizeof(*con)) {
2454 TRAP_ERROR();
2455 error = EINVAL;
2456 break;
2457 }
2458 con->path[sizeof(con->path) - 1] = '\0';
2459 con->ourhook[sizeof(con->ourhook) - 1] = '\0';
2460 con->peerhook[sizeof(con->peerhook) - 1] = '\0';
2461 /* Don't forget we get a reference.. */
2462 error = ng_path2noderef(here, con->path, &node2, NULL);
2463 if (error)
2464 break;
2465 error = ng_con_nodes(item, here, con->ourhook,
2466 node2, con->peerhook);
2467 NG_NODE_UNREF(node2);
2468 break;
2469 }
2470 case NGM_NAME:
2471 {
2472 struct ngm_name *const nam = (struct ngm_name *) msg->data;
2473
2474 if (msg->header.arglen != sizeof(*nam)) {
2475 TRAP_ERROR();
2476 error = EINVAL;
2477 break;
2478 }
2479 nam->name[sizeof(nam->name) - 1] = '\0';
2480 error = ng_name_node(here, nam->name);
2481 break;
2482 }
2483 case NGM_RMHOOK:
2484 {
2485 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data;
2486 hook_p hook;
2487
2488 if (msg->header.arglen != sizeof(*rmh)) {
2489 TRAP_ERROR();
2490 error = EINVAL;
2491 break;
2492 }
2493 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0';
2494 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL)
2495 ng_destroy_hook(hook);
2496 break;
2497 }
2498 case NGM_NODEINFO:
2499 {
2500 struct nodeinfo *ni;
2501
2502 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT);
2503 if (resp == NULL) {
2504 error = ENOMEM;
2505 break;
2506 }
2507
2508 /* Fill in node info */
2509 ni = (struct nodeinfo *) resp->data;
2510 if (NG_NODE_HAS_NAME(here))
2511 strcpy(ni->name, NG_NODE_NAME(here));
2512 strcpy(ni->type, here->nd_type->name);
2513 ni->id = ng_node2ID(here);
2514 ni->hooks = here->nd_numhooks;
2515 break;
2516 }
2517 case NGM_LISTHOOKS:
2518 {
2519 const int nhooks = here->nd_numhooks;
2520 struct hooklist *hl;
2521 struct nodeinfo *ni;
2522 hook_p hook;
2523
2524 /* Get response struct */
2525 NG_MKRESPONSE(resp, msg, sizeof(*hl)
2526 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT);
2527 if (resp == NULL) {
2528 error = ENOMEM;
2529 break;
2530 }
2531 hl = (struct hooklist *) resp->data;
2532 ni = &hl->nodeinfo;
2533
2534 /* Fill in node info */
2535 if (NG_NODE_HAS_NAME(here))
2536 strcpy(ni->name, NG_NODE_NAME(here));
2537 strcpy(ni->type, here->nd_type->name);
2538 ni->id = ng_node2ID(here);
2539
2540 /* Cycle through the linked list of hooks */
2541 ni->hooks = 0;
2542 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) {
2543 struct linkinfo *const link = &hl->link[ni->hooks];
2544
2545 if (ni->hooks >= nhooks) {
2546 log(LOG_ERR, "%s: number of %s changed\n",
2547 __func__, "hooks");
2548 break;
2549 }
2550 if (NG_HOOK_NOT_VALID(hook))
2551 continue;
2552 strcpy(link->ourhook, NG_HOOK_NAME(hook));
2553 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook));
2554 if (NG_PEER_NODE_NAME(hook)[0] != '\0')
2555 strcpy(link->nodeinfo.name,
2556 NG_PEER_NODE_NAME(hook));
2557 strcpy(link->nodeinfo.type,
2558 NG_PEER_NODE(hook)->nd_type->name);
2559 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook));
2560 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks;
2561 ni->hooks++;
2562 }
2563 break;
2564 }
2565
2566 case NGM_LISTNAMES:
2567 case NGM_LISTNODES:
2568 {
2569 const int unnamed = (msg->header.cmd == NGM_LISTNODES);
2570 struct namelist *nl;
2571 node_p node;
2572 int num = 0, i;
2573
2574 mtx_lock(&ng_namehash_mtx);
2575 /* Count number of nodes */
2576 for (i = 0; i < NG_NAME_HASH_SIZE; i++) {
2577 LIST_FOREACH(node, &ng_name_hash[i], nd_nodes) {
2578 if (NG_NODE_IS_VALID(node) &&
2579 (unnamed || NG_NODE_HAS_NAME(node))) {
2580 num++;
2581 }
2582 }
2583 }
2584 mtx_unlock(&ng_namehash_mtx);
2585
2586 /* Get response struct */
2587 NG_MKRESPONSE(resp, msg, sizeof(*nl)
2588 + (num * sizeof(struct nodeinfo)), M_NOWAIT);
2589 if (resp == NULL) {
2590 error = ENOMEM;
2591 break;
2592 }
2593 nl = (struct namelist *) resp->data;
2594
2595 /* Cycle through the linked list of nodes */
2596 nl->numnames = 0;
2597 mtx_lock(&ng_namehash_mtx);
2598 for (i = 0; i < NG_NAME_HASH_SIZE; i++) {
2599 LIST_FOREACH(node, &ng_name_hash[i], nd_nodes) {
2600 struct nodeinfo *const np =
2601 &nl->nodeinfo[nl->numnames];
2602
2603 if (NG_NODE_NOT_VALID(node))
2604 continue;
2605 if (!unnamed && (! NG_NODE_HAS_NAME(node)))
2606 continue;
2607 if (nl->numnames >= num) {
2608 log(LOG_ERR, "%s: number of nodes changed\n",
2609 __func__);
2610 break;
2611 }
2612 if (NG_NODE_HAS_NAME(node))
2613 strcpy(np->name, NG_NODE_NAME(node));
2614 strcpy(np->type, node->nd_type->name);
2615 np->id = ng_node2ID(node);
2616 np->hooks = node->nd_numhooks;
2617 nl->numnames++;
2618 }
2619 }
2620 mtx_unlock(&ng_namehash_mtx);
2621 break;
2622 }
2623
2624 case NGM_LISTTYPES:
2625 {
2626 struct typelist *tl;
2627 struct ng_type *type;
2628 int num = 0;
2629
2630 mtx_lock(&ng_typelist_mtx);
2631 /* Count number of types */
2632 LIST_FOREACH(type, &ng_typelist, types) {
2633 num++;
2634 }
2635 mtx_unlock(&ng_typelist_mtx);
2636
2637 /* Get response struct */
2638 NG_MKRESPONSE(resp, msg, sizeof(*tl)
2639 + (num * sizeof(struct typeinfo)), M_NOWAIT);
2640 if (resp == NULL) {
2641 error = ENOMEM;
2642 break;
2643 }
2644 tl = (struct typelist *) resp->data;
2645
2646 /* Cycle through the linked list of types */
2647 tl->numtypes = 0;
2648 mtx_lock(&ng_typelist_mtx);
2649 LIST_FOREACH(type, &ng_typelist, types) {
2650 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes];
2651
2652 if (tl->numtypes >= num) {
2653 log(LOG_ERR, "%s: number of %s changed\n",
2654 __func__, "types");
2655 break;
2656 }
2657 strcpy(tp->type_name, type->name);
2658 tp->numnodes = type->refs - 1; /* don't count list */
2659 tl->numtypes++;
2660 }
2661 mtx_unlock(&ng_typelist_mtx);
2662 break;
2663 }
2664
2665 case NGM_BINARY2ASCII:
2666 {
2667 int bufSize = 20 * 1024; /* XXX hard coded constant */
2668 const struct ng_parse_type *argstype;
2669 const struct ng_cmdlist *c;
2670 struct ng_mesg *binary, *ascii;
2671
2672 /* Data area must contain a valid netgraph message */
2673 binary = (struct ng_mesg *)msg->data;
2674 if (msg->header.arglen < sizeof(struct ng_mesg) ||
2675 (msg->header.arglen - sizeof(struct ng_mesg) <
2676 binary->header.arglen)) {
2677 TRAP_ERROR();
2678 error = EINVAL;
2679 break;
2680 }
2681
2682 /* Get a response message with lots of room */
2683 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT);
2684 if (resp == NULL) {
2685 error = ENOMEM;
2686 break;
2687 }
2688 ascii = (struct ng_mesg *)resp->data;
2689
2690 /* Copy binary message header to response message payload */
2691 bcopy(binary, ascii, sizeof(*binary));
2692
2693 /* Find command by matching typecookie and command number */
2694 for (c = here->nd_type->cmdlist;
2695 c != NULL && c->name != NULL; c++) {
2696 if (binary->header.typecookie == c->cookie
2697 && binary->header.cmd == c->cmd)
2698 break;
2699 }
2700 if (c == NULL || c->name == NULL) {
2701 for (c = ng_generic_cmds; c->name != NULL; c++) {
2702 if (binary->header.typecookie == c->cookie
2703 && binary->header.cmd == c->cmd)
2704 break;
2705 }
2706 if (c->name == NULL) {
2707 NG_FREE_MSG(resp);
2708 error = ENOSYS;
2709 break;
2710 }
2711 }
2712
2713 /* Convert command name to ASCII */
2714 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr),
2715 "%s", c->name);
2716
2717 /* Convert command arguments to ASCII */
2718 argstype = (binary->header.flags & NGF_RESP) ?
2719 c->respType : c->mesgType;
2720 if (argstype == NULL) {
2721 *ascii->data = '\0';
2722 } else {
2723 if ((error = ng_unparse(argstype,
2724 (u_char *)binary->data,
2725 ascii->data, bufSize)) != 0) {
2726 NG_FREE_MSG(resp);
2727 break;
2728 }
2729 }
2730
2731 /* Return the result as struct ng_mesg plus ASCII string */
2732 bufSize = strlen(ascii->data) + 1;
2733 ascii->header.arglen = bufSize;
2734 resp->header.arglen = sizeof(*ascii) + bufSize;
2735 break;
2736 }
2737
2738 case NGM_ASCII2BINARY:
2739 {
2740 int bufSize = 2000; /* XXX hard coded constant */
2741 const struct ng_cmdlist *c;
2742 const struct ng_parse_type *argstype;
2743 struct ng_mesg *ascii, *binary;
2744 int off = 0;
2745
2746 /* Data area must contain at least a struct ng_mesg + '\0' */
2747 ascii = (struct ng_mesg *)msg->data;
2748 if ((msg->header.arglen < sizeof(*ascii) + 1) ||
2749 (ascii->header.arglen < 1) ||
2750 (msg->header.arglen < sizeof(*ascii) +
2751 ascii->header.arglen)) {
2752 TRAP_ERROR();
2753 error = EINVAL;
2754 break;
2755 }
2756 ascii->data[ascii->header.arglen - 1] = '\0';
2757
2758 /* Get a response message with lots of room */
2759 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT);
2760 if (resp == NULL) {
2761 error = ENOMEM;
2762 break;
2763 }
2764 binary = (struct ng_mesg *)resp->data;
2765
2766 /* Copy ASCII message header to response message payload */
2767 bcopy(ascii, binary, sizeof(*ascii));
2768
2769 /* Find command by matching ASCII command string */
2770 for (c = here->nd_type->cmdlist;
2771 c != NULL && c->name != NULL; c++) {
2772 if (strcmp(ascii->header.cmdstr, c->name) == 0)
2773 break;
2774 }
2775 if (c == NULL || c->name == NULL) {
2776 for (c = ng_generic_cmds; c->name != NULL; c++) {
2777 if (strcmp(ascii->header.cmdstr, c->name) == 0)
2778 break;
2779 }
2780 if (c->name == NULL) {
2781 NG_FREE_MSG(resp);
2782 error = ENOSYS;
2783 break;
2784 }
2785 }
2786
2787 /* Convert command name to binary */
2788 binary->header.cmd = c->cmd;
2789 binary->header.typecookie = c->cookie;
2790
2791 /* Convert command arguments to binary */
2792 argstype = (binary->header.flags & NGF_RESP) ?
2793 c->respType : c->mesgType;
2794 if (argstype == NULL) {
2795 bufSize = 0;
2796 } else {
2797 if ((error = ng_parse(argstype, ascii->data,
2798 &off, (u_char *)binary->data, &bufSize)) != 0) {
2799 NG_FREE_MSG(resp);
2800 break;
2801 }
2802 }
2803
2804 /* Return the result */
2805 binary->header.arglen = bufSize;
2806 resp->header.arglen = sizeof(*binary) + bufSize;
2807 break;
2808 }
2809
2810 case NGM_TEXT_CONFIG:
2811 case NGM_TEXT_STATUS:
2812 /*
2813 * This one is tricky as it passes the command down to the
2814 * actual node, even though it is a generic type command.
2815 * This means we must assume that the item/msg is already freed
2816 * when control passes back to us.
2817 */
2818 if (here->nd_type->rcvmsg != NULL) {
2819 NGI_MSG(item) = msg; /* put it back as we found it */
2820 return((*here->nd_type->rcvmsg)(here, item, lasthook));
2821 }
2822 /* Fall through if rcvmsg not supported */
2823 default:
2824 TRAP_ERROR();
2825 error = EINVAL;
2826 }
2827 /*
2828 * Sometimes a generic message may be statically allocated
2829 * to avoid problems with allocating when in tight memeory situations.
2830 * Don't free it if it is so.
2831 * I break them appart here, because erros may cause a free if the item
2832 * in which case we'd be doing it twice.
2833 * they are kept together above, to simplify freeing.
2834 */
2835 out:
2836 NG_RESPOND_MSG(error, here, item, resp);
2837 if (msg)
2838 NG_FREE_MSG(msg);
2839 return (error);
2840 }
2841
2842 /************************************************************************
2843 Queue element get/free routines
2844 ************************************************************************/
2845
2846 uma_zone_t ng_qzone;
2847 uma_zone_t ng_qdzone;
2848 static int maxalloc = 4096;/* limit the damage of a leak */
2849 static int maxdata = 512; /* limit the damage of a DoS */
2850
2851 TUNABLE_INT("net.graph.maxalloc", &maxalloc);
2852 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc,
2853 0, "Maximum number of non-data queue items to allocate");
2854 TUNABLE_INT("net.graph.maxdata", &maxdata);
2855 SYSCTL_INT(_net_graph, OID_AUTO, maxdata, CTLFLAG_RDTUN, &maxdata,
2856 0, "Maximum number of data queue items to allocate");
2857
2858 #ifdef NETGRAPH_DEBUG
2859 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist);
2860 static int allocated; /* number of items malloc'd */
2861 #endif
2862
2863 /*
2864 * Get a queue entry.
2865 * This is usually called when a packet first enters netgraph.
2866 * By definition, this is usually from an interrupt, or from a user.
2867 * Users are not so important, but try be quick for the times that it's
2868 * an interrupt.
2869 */
2870 static __inline item_p
2871 ng_alloc_item(int type, int flags)
2872 {
2873 item_p item;
2874
2875 KASSERT(((type & ~NGQF_TYPE) == 0),
2876 ("%s: incorrect item type: %d", __func__, type));
2877
2878 item = uma_zalloc((type == NGQF_DATA)?ng_qdzone:ng_qzone,
2879 ((flags & NG_WAITOK) ? M_WAITOK : M_NOWAIT) | M_ZERO);
2880
2881 if (item) {
2882 item->el_flags = type;
2883 #ifdef NETGRAPH_DEBUG
2884 mtx_lock(&ngq_mtx);
2885 TAILQ_INSERT_TAIL(&ng_itemlist, item, all);
2886 allocated++;
2887 mtx_unlock(&ngq_mtx);
2888 #endif
2889 }
2890
2891 return (item);
2892 }
2893
2894 /*
2895 * Release a queue entry
2896 */
2897 void
2898 ng_free_item(item_p item)
2899 {
2900 /*
2901 * The item may hold resources on it's own. We need to free
2902 * these before we can free the item. What they are depends upon
2903 * what kind of item it is. it is important that nodes zero
2904 * out pointers to resources that they remove from the item
2905 * or we release them again here.
2906 */
2907 switch (item->el_flags & NGQF_TYPE) {
2908 case NGQF_DATA:
2909 /* If we have an mbuf still attached.. */
2910 NG_FREE_M(_NGI_M(item));
2911 break;
2912 case NGQF_MESG:
2913 _NGI_RETADDR(item) = 0;
2914 NG_FREE_MSG(_NGI_MSG(item));
2915 break;
2916 case NGQF_FN:
2917 case NGQF_FN2:
2918 /* nothing to free really, */
2919 _NGI_FN(item) = NULL;
2920 _NGI_ARG1(item) = NULL;
2921 _NGI_ARG2(item) = 0;
2922 break;
2923 }
2924 /* If we still have a node or hook referenced... */
2925 _NGI_CLR_NODE(item);
2926 _NGI_CLR_HOOK(item);
2927
2928 #ifdef NETGRAPH_DEBUG
2929 mtx_lock(&ngq_mtx);
2930 TAILQ_REMOVE(&ng_itemlist, item, all);
2931 allocated--;
2932 mtx_unlock(&ngq_mtx);
2933 #endif
2934 uma_zfree(((item->el_flags & NGQF_TYPE) == NGQF_DATA)?
2935 ng_qdzone:ng_qzone, item);
2936 }
2937
2938 /*
2939 * Change type of the queue entry.
2940 * Possibly reallocates it from another UMA zone.
2941 */
2942 static __inline item_p
2943 ng_realloc_item(item_p pitem, int type, int flags)
2944 {
2945 item_p item;
2946 int from, to;
2947
2948 KASSERT((pitem != NULL), ("%s: can't reallocate NULL", __func__));
2949 KASSERT(((type & ~NGQF_TYPE) == 0),
2950 ("%s: incorrect item type: %d", __func__, type));
2951
2952 from = ((pitem->el_flags & NGQF_TYPE) == NGQF_DATA);
2953 to = (type == NGQF_DATA);
2954 if (from != to) {
2955 /* If reallocation is required do it and copy item. */
2956 if ((item = ng_alloc_item(type, flags)) == NULL) {
2957 ng_free_item(pitem);
2958 return (NULL);
2959 }
2960 *item = *pitem;
2961 ng_free_item(pitem);
2962 } else
2963 item = pitem;
2964 item->el_flags = (item->el_flags & ~NGQF_TYPE) | type;
2965
2966 return (item);
2967 }
2968
2969 /************************************************************************
2970 Module routines
2971 ************************************************************************/
2972
2973 /*
2974 * Handle the loading/unloading of a netgraph node type module
2975 */
2976 int
2977 ng_mod_event(module_t mod, int event, void *data)
2978 {
2979 struct ng_type *const type = data;
2980 int s, error = 0;
2981
2982 switch (event) {
2983 case MOD_LOAD:
2984
2985 /* Register new netgraph node type */
2986 s = splnet();
2987 if ((error = ng_newtype(type)) != 0) {
2988 splx(s);
2989 break;
2990 }
2991
2992 /* Call type specific code */
2993 if (type->mod_event != NULL)
2994 if ((error = (*type->mod_event)(mod, event, data))) {
2995 mtx_lock(&ng_typelist_mtx);
2996 type->refs--; /* undo it */
2997 LIST_REMOVE(type, types);
2998 mtx_unlock(&ng_typelist_mtx);
2999 }
3000 splx(s);
3001 break;
3002
3003 case MOD_UNLOAD:
3004 s = splnet();
3005 if (type->refs > 1) { /* make sure no nodes exist! */
3006 error = EBUSY;
3007 } else {
3008 if (type->refs == 0) {
3009 /* failed load, nothing to undo */
3010 splx(s);
3011 break;
3012 }
3013 if (type->mod_event != NULL) { /* check with type */
3014 error = (*type->mod_event)(mod, event, data);
3015 if (error != 0) { /* type refuses.. */
3016 splx(s);
3017 break;
3018 }
3019 }
3020 mtx_lock(&ng_typelist_mtx);
3021 LIST_REMOVE(type, types);
3022 mtx_unlock(&ng_typelist_mtx);
3023 }
3024 splx(s);
3025 break;
3026
3027 default:
3028 if (type->mod_event != NULL)
3029 error = (*type->mod_event)(mod, event, data);
3030 else
3031 error = EOPNOTSUPP; /* XXX ? */
3032 break;
3033 }
3034 return (error);
3035 }
3036
3037 /*
3038 * Handle loading and unloading for this code.
3039 * The only thing we need to link into is the NETISR strucure.
3040 */
3041 static int
3042 ngb_mod_event(module_t mod, int event, void *data)
3043 {
3044 int error = 0;
3045
3046 switch (event) {
3047 case MOD_LOAD:
3048 /* Initialize everything. */
3049 NG_WORKLIST_LOCK_INIT();
3050 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL,
3051 MTX_DEF);
3052 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL,
3053 MTX_DEF);
3054 mtx_init(&ng_namehash_mtx, "netgraph namehash mutex", NULL,
3055 MTX_DEF);
3056 mtx_init(&ng_topo_mtx, "netgraph topology mutex", NULL,
3057 MTX_DEF);
3058 #ifdef NETGRAPH_DEBUG
3059 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL,
3060 MTX_DEF);
3061 mtx_init(&ngq_mtx, "netgraph item list mutex", NULL,
3062 MTX_DEF);
3063 #endif
3064 ng_qzone = uma_zcreate("NetGraph items", sizeof(struct ng_item),
3065 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0);
3066 uma_zone_set_max(ng_qzone, maxalloc);
3067 ng_qdzone = uma_zcreate("NetGraph data items", sizeof(struct ng_item),
3068 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0);
3069 uma_zone_set_max(ng_qdzone, maxdata);
3070 netisr_register(NETISR_NETGRAPH, (netisr_t *)ngintr, NULL,
3071 NETISR_MPSAFE);
3072 break;
3073 case MOD_UNLOAD:
3074 /* You can't unload it because an interface may be using it. */
3075 error = EBUSY;
3076 break;
3077 default:
3078 error = EOPNOTSUPP;
3079 break;
3080 }
3081 return (error);
3082 }
3083
3084 static moduledata_t netgraph_mod = {
3085 "netgraph",
3086 ngb_mod_event,
3087 (NULL)
3088 };
3089 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_MIDDLE);
3090 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family");
3091 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,"");
3092 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, "");
3093
3094 #ifdef NETGRAPH_DEBUG
3095 void
3096 dumphook (hook_p hook, char *file, int line)
3097 {
3098 printf("hook: name %s, %d refs, Last touched:\n",
3099 _NG_HOOK_NAME(hook), hook->hk_refs);
3100 printf(" Last active @ %s, line %d\n",
3101 hook->lastfile, hook->lastline);
3102 if (line) {
3103 printf(" problem discovered at file %s, line %d\n", file, line);
3104 }
3105 }
3106
3107 void
3108 dumpnode(node_p node, char *file, int line)
3109 {
3110 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n",
3111 _NG_NODE_ID(node), node->nd_type->name,
3112 node->nd_numhooks, node->nd_flags,
3113 node->nd_refs, node->nd_name);
3114 printf(" Last active @ %s, line %d\n",
3115 node->lastfile, node->lastline);
3116 if (line) {
3117 printf(" problem discovered at file %s, line %d\n", file, line);
3118 }
3119 }
3120
3121 void
3122 dumpitem(item_p item, char *file, int line)
3123 {
3124 printf(" ACTIVE item, last used at %s, line %d",
3125 item->lastfile, item->lastline);
3126 switch(item->el_flags & NGQF_TYPE) {
3127 case NGQF_DATA:
3128 printf(" - [data]\n");
3129 break;
3130 case NGQF_MESG:
3131 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item));
3132 break;
3133 case NGQF_FN:
3134 printf(" - fn@%p (%p, %p, %p, %d (%x))\n",
3135 _NGI_FN(item),
3136 _NGI_NODE(item),
3137 _NGI_HOOK(item),
3138 item->body.fn.fn_arg1,
3139 item->body.fn.fn_arg2,
3140 item->body.fn.fn_arg2);
3141 break;
3142 case NGQF_FN2:
3143 printf(" - fn2@%p (%p, %p, %p, %d (%x))\n",
3144 _NGI_FN2(item),
3145 _NGI_NODE(item),
3146 _NGI_HOOK(item),
3147 item->body.fn.fn_arg1,
3148 item->body.fn.fn_arg2,
3149 item->body.fn.fn_arg2);
3150 break;
3151 }
3152 if (line) {
3153 printf(" problem discovered at file %s, line %d\n", file, line);
3154 if (_NGI_NODE(item)) {
3155 printf("node %p ([%x])\n",
3156 _NGI_NODE(item), ng_node2ID(_NGI_NODE(item)));
3157 }
3158 }
3159 }
3160
3161 static void
3162 ng_dumpitems(void)
3163 {
3164 item_p item;
3165 int i = 1;
3166 TAILQ_FOREACH(item, &ng_itemlist, all) {
3167 printf("[%d] ", i++);
3168 dumpitem(item, NULL, 0);
3169 }
3170 }
3171
3172 static void
3173 ng_dumpnodes(void)
3174 {
3175 node_p node;
3176 int i = 1;
3177 mtx_lock(&ng_nodelist_mtx);
3178 SLIST_FOREACH(node, &ng_allnodes, nd_all) {
3179 printf("[%d] ", i++);
3180 dumpnode(node, NULL, 0);
3181 }
3182 mtx_unlock(&ng_nodelist_mtx);
3183 }
3184
3185 static void
3186 ng_dumphooks(void)
3187 {
3188 hook_p hook;
3189 int i = 1;
3190 mtx_lock(&ng_nodelist_mtx);
3191 SLIST_FOREACH(hook, &ng_allhooks, hk_all) {
3192 printf("[%d] ", i++);
3193 dumphook(hook, NULL, 0);
3194 }
3195 mtx_unlock(&ng_nodelist_mtx);
3196 }
3197
3198 static int
3199 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS)
3200 {
3201 int error;
3202 int val;
3203 int i;
3204
3205 val = allocated;
3206 i = 1;
3207 error = sysctl_handle_int(oidp, &val, 0, req);
3208 if (error != 0 || req->newptr == NULL)
3209 return (error);
3210 if (val == 42) {
3211 ng_dumpitems();
3212 ng_dumpnodes();
3213 ng_dumphooks();
3214 }
3215 return (0);
3216 }
3217
3218 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW,
3219 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items");
3220 #endif /* NETGRAPH_DEBUG */
3221
3222
3223 /***********************************************************************
3224 * Worklist routines
3225 **********************************************************************/
3226 /* NETISR thread enters here */
3227 /*
3228 * Pick a node off the list of nodes with work,
3229 * try get an item to process off it.
3230 * If there are no more, remove the node from the list.
3231 */
3232 static void
3233 ngintr(void)
3234 {
3235 for (;;) {
3236 node_p node;
3237
3238 /* Get node from the worklist. */
3239 NG_WORKLIST_LOCK();
3240 node = STAILQ_FIRST(&ng_worklist);
3241 if (!node) {
3242 NG_WORKLIST_UNLOCK();
3243 break;
3244 }
3245 STAILQ_REMOVE_HEAD(&ng_worklist, nd_input_queue.q_work);
3246 NG_WORKLIST_UNLOCK();
3247 CTR3(KTR_NET, "%20s: node [%x] (%p) taken off worklist",
3248 __func__, node->nd_ID, node);
3249 /*
3250 * We have the node. We also take over the reference
3251 * that the list had on it.
3252 * Now process as much as you can, until it won't
3253 * let you have another item off the queue.
3254 * All this time, keep the reference
3255 * that lets us be sure that the node still exists.
3256 * Let the reference go at the last minute.
3257 */
3258 for (;;) {
3259 item_p item;
3260 int rw;
3261
3262 NG_QUEUE_LOCK(&node->nd_input_queue);
3263 item = ng_dequeue(node, &rw);
3264 if (item == NULL) {
3265 node->nd_input_queue.q_flags2 &= ~NGQ2_WORKQ;
3266 NG_QUEUE_UNLOCK(&node->nd_input_queue);
3267 break; /* go look for another node */
3268 } else {
3269 NG_QUEUE_UNLOCK(&node->nd_input_queue);
3270 NGI_GET_NODE(item, node); /* zaps stored node */
3271 ng_apply_item(node, item, rw);
3272 NG_NODE_UNREF(node);
3273 }
3274 }
3275 NG_NODE_UNREF(node);
3276 }
3277 }
3278
3279 /*
3280 * XXX
3281 * It's posible that a debugging NG_NODE_REF may need
3282 * to be outside the mutex zone
3283 */
3284 static void
3285 ng_worklist_add(node_p node)
3286 {
3287
3288 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED);
3289
3290 if ((node->nd_input_queue.q_flags2 & NGQ2_WORKQ) == 0) {
3291 /*
3292 * If we are not already on the work queue,
3293 * then put us on.
3294 */
3295 node->nd_input_queue.q_flags2 |= NGQ2_WORKQ;
3296 NG_NODE_REF(node); /* XXX fafe in mutex? */
3297 NG_WORKLIST_LOCK();
3298 STAILQ_INSERT_TAIL(&ng_worklist, node, nd_input_queue.q_work);
3299 NG_WORKLIST_UNLOCK();
3300 schednetisr(NETISR_NETGRAPH);
3301 CTR3(KTR_NET, "%20s: node [%x] (%p) put on worklist", __func__,
3302 node->nd_ID, node);
3303 } else {
3304 CTR3(KTR_NET, "%20s: node [%x] (%p) already on worklist",
3305 __func__, node->nd_ID, node);
3306 }
3307 }
3308
3309
3310 /***********************************************************************
3311 * Externally useable functions to set up a queue item ready for sending
3312 ***********************************************************************/
3313
3314 #ifdef NETGRAPH_DEBUG
3315 #define ITEM_DEBUG_CHECKS \
3316 do { \
3317 if (NGI_NODE(item) ) { \
3318 printf("item already has node"); \
3319 kdb_enter(KDB_WHY_NETGRAPH, "has node"); \
3320 NGI_CLR_NODE(item); \
3321 } \
3322 if (NGI_HOOK(item) ) { \
3323 printf("item already has hook"); \
3324 kdb_enter(KDB_WHY_NETGRAPH, "has hook"); \
3325 NGI_CLR_HOOK(item); \
3326 } \
3327 } while (0)
3328 #else
3329 #define ITEM_DEBUG_CHECKS
3330 #endif
3331
3332 /*
3333 * Put mbuf into the item.
3334 * Hook and node references will be removed when the item is dequeued.
3335 * (or equivalent)
3336 * (XXX) Unsafe because no reference held by peer on remote node.
3337 * remote node might go away in this timescale.
3338 * We know the hooks can't go away because that would require getting
3339 * a writer item on both nodes and we must have at least a reader
3340 * here to be able to do this.
3341 * Note that the hook loaded is the REMOTE hook.
3342 *
3343 * This is possibly in the critical path for new data.
3344 */
3345 item_p
3346 ng_package_data(struct mbuf *m, int flags)
3347 {
3348 item_p item;
3349
3350 if ((item = ng_alloc_item(NGQF_DATA, flags)) == NULL) {
3351 NG_FREE_M(m);
3352 return (NULL);
3353 }
3354 ITEM_DEBUG_CHECKS;
3355 item->el_flags |= NGQF_READER;
3356 NGI_M(item) = m;
3357 return (item);
3358 }
3359
3360 /*
3361 * Allocate a queue item and put items into it..
3362 * Evaluate the address as this will be needed to queue it and
3363 * to work out what some of the fields should be.
3364 * Hook and node references will be removed when the item is dequeued.
3365 * (or equivalent)
3366 */
3367 item_p
3368 ng_package_msg(struct ng_mesg *msg, int flags)
3369 {
3370 item_p item;
3371
3372 if ((item = ng_alloc_item(NGQF_MESG, flags)) == NULL) {
3373 NG_FREE_MSG(msg);
3374 return (NULL);
3375 }
3376 ITEM_DEBUG_CHECKS;
3377 /* Messages items count as writers unless explicitly exempted. */
3378 if (msg->header.cmd & NGM_READONLY)
3379 item->el_flags |= NGQF_READER;
3380 else
3381 item->el_flags |= NGQF_WRITER;
3382 /*
3383 * Set the current lasthook into the queue item
3384 */
3385 NGI_MSG(item) = msg;
3386 NGI_RETADDR(item) = 0;
3387 return (item);
3388 }
3389
3390
3391
3392 #define SET_RETADDR(item, here, retaddr) \
3393 do { /* Data or fn items don't have retaddrs */ \
3394 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \
3395 if (retaddr) { \
3396 NGI_RETADDR(item) = retaddr; \
3397 } else { \
3398 /* \
3399 * The old return address should be ok. \
3400 * If there isn't one, use the address \
3401 * here. \
3402 */ \
3403 if (NGI_RETADDR(item) == 0) { \
3404 NGI_RETADDR(item) \
3405 = ng_node2ID(here); \
3406 } \
3407 } \
3408 } \
3409 } while (0)
3410
3411 int
3412 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr)
3413 {
3414 hook_p peer;
3415 node_p peernode;
3416 ITEM_DEBUG_CHECKS;
3417 /*
3418 * Quick sanity check..
3419 * Since a hook holds a reference on it's node, once we know
3420 * that the peer is still connected (even if invalid,) we know
3421 * that the peer node is present, though maybe invalid.
3422 */
3423 if ((hook == NULL) ||
3424 NG_HOOK_NOT_VALID(hook) ||
3425 NG_HOOK_NOT_VALID(peer = NG_HOOK_PEER(hook)) ||
3426 NG_NODE_NOT_VALID(peernode = NG_PEER_NODE(hook))) {
3427 NG_FREE_ITEM(item);
3428 TRAP_ERROR();
3429 return (ENETDOWN);
3430 }
3431
3432 /*
3433 * Transfer our interest to the other (peer) end.
3434 */
3435 NG_HOOK_REF(peer);
3436 NG_NODE_REF(peernode);
3437 NGI_SET_HOOK(item, peer);
3438 NGI_SET_NODE(item, peernode);
3439 SET_RETADDR(item, here, retaddr);
3440 return (0);
3441 }
3442
3443 int
3444 ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr)
3445 {
3446 node_p dest = NULL;
3447 hook_p hook = NULL;
3448 int error;
3449
3450 ITEM_DEBUG_CHECKS;
3451 /*
3452 * Note that ng_path2noderef increments the reference count
3453 * on the node for us if it finds one. So we don't have to.
3454 */
3455 error = ng_path2noderef(here, address, &dest, &hook);
3456 if (error) {
3457 NG_FREE_ITEM(item);
3458 return (error);
3459 }
3460 NGI_SET_NODE(item, dest);
3461 if ( hook) {
3462 NG_HOOK_REF(hook); /* don't let it go while on the queue */
3463 NGI_SET_HOOK(item, hook);
3464 }
3465 SET_RETADDR(item, here, retaddr);
3466 return (0);
3467 }
3468
3469 int
3470 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr)
3471 {
3472 node_p dest;
3473
3474 ITEM_DEBUG_CHECKS;
3475 /*
3476 * Find the target node.
3477 */
3478 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */
3479 if (dest == NULL) {
3480 NG_FREE_ITEM(item);
3481 TRAP_ERROR();
3482 return(EINVAL);
3483 }
3484 /* Fill out the contents */
3485 NGI_SET_NODE(item, dest);
3486 NGI_CLR_HOOK(item);
3487 SET_RETADDR(item, here, retaddr);
3488 return (0);
3489 }
3490
3491 /*
3492 * special case to send a message to self (e.g. destroy node)
3493 * Possibly indicate an arrival hook too.
3494 * Useful for removing that hook :-)
3495 */
3496 item_p
3497 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg)
3498 {
3499 item_p item;
3500
3501 /*
3502 * Find the target node.
3503 * If there is a HOOK argument, then use that in preference
3504 * to the address.
3505 */
3506 if ((item = ng_alloc_item(NGQF_MESG, NG_NOFLAGS)) == NULL) {
3507 NG_FREE_MSG(msg);
3508 return (NULL);
3509 }
3510
3511 /* Fill out the contents */
3512 item->el_flags |= NGQF_WRITER;
3513 NG_NODE_REF(here);
3514 NGI_SET_NODE(item, here);
3515 if (hook) {
3516 NG_HOOK_REF(hook);
3517 NGI_SET_HOOK(item, hook);
3518 }
3519 NGI_MSG(item) = msg;
3520 NGI_RETADDR(item) = ng_node2ID(here);
3521 return (item);
3522 }
3523
3524 /*
3525 * Send ng_item_fn function call to the specified node.
3526 */
3527
3528 int
3529 ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2)
3530 {
3531
3532 return ng_send_fn1(node, hook, fn, arg1, arg2, NG_NOFLAGS);
3533 }
3534
3535 int
3536 ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2,
3537 int flags)
3538 {
3539 item_p item;
3540
3541 if ((item = ng_alloc_item(NGQF_FN, flags)) == NULL) {
3542 return (ENOMEM);
3543 }
3544 item->el_flags |= NGQF_WRITER;
3545 NG_NODE_REF(node); /* and one for the item */
3546 NGI_SET_NODE(item, node);
3547 if (hook) {
3548 NG_HOOK_REF(hook);
3549 NGI_SET_HOOK(item, hook);
3550 }
3551 NGI_FN(item) = fn;
3552 NGI_ARG1(item) = arg1;
3553 NGI_ARG2(item) = arg2;
3554 return(ng_snd_item(item, flags));
3555 }
3556
3557 /*
3558 * Send ng_item_fn2 function call to the specified node.
3559 *
3560 * If an optional pitem parameter is supplied, its apply
3561 * callback will be copied to the new item. If also NG_REUSE_ITEM
3562 * flag is set, no new item will be allocated, but pitem will
3563 * be used.
3564 */
3565 int
3566 ng_send_fn2(node_p node, hook_p hook, item_p pitem, ng_item_fn2 *fn, void *arg1,
3567 int arg2, int flags)
3568 {
3569 item_p item;
3570
3571 KASSERT((pitem != NULL || (flags & NG_REUSE_ITEM) == 0),
3572 ("%s: NG_REUSE_ITEM but no pitem", __func__));
3573
3574 /*
3575 * Allocate a new item if no supplied or
3576 * if we can't use supplied one.
3577 */
3578 if (pitem == NULL || (flags & NG_REUSE_ITEM) == 0) {
3579 if ((item = ng_alloc_item(NGQF_FN2, flags)) == NULL)
3580 return (ENOMEM);
3581 if (pitem != NULL)
3582 item->apply = pitem->apply;
3583 } else {
3584 if ((item = ng_realloc_item(pitem, NGQF_FN2, flags)) == NULL)
3585 return (ENOMEM);
3586 }
3587
3588 item->el_flags = (item->el_flags & ~NGQF_RW) | NGQF_WRITER;
3589 NG_NODE_REF(node); /* and one for the item */
3590 NGI_SET_NODE(item, node);
3591 if (hook) {
3592 NG_HOOK_REF(hook);
3593 NGI_SET_HOOK(item, hook);
3594 }
3595 NGI_FN2(item) = fn;
3596 NGI_ARG1(item) = arg1;
3597 NGI_ARG2(item) = arg2;
3598 return(ng_snd_item(item, flags));
3599 }
3600
3601 /*
3602 * Official timeout routines for Netgraph nodes.
3603 */
3604 static void
3605 ng_callout_trampoline(void *arg)
3606 {
3607 item_p item = arg;
3608
3609 ng_snd_item(item, 0);
3610 }
3611
3612
3613 int
3614 ng_callout(struct callout *c, node_p node, hook_p hook, int ticks,
3615 ng_item_fn *fn, void * arg1, int arg2)
3616 {
3617 item_p item, oitem;
3618
3619 if ((item = ng_alloc_item(NGQF_FN, NG_NOFLAGS)) == NULL)
3620 return (ENOMEM);
3621
3622 item->el_flags |= NGQF_WRITER;
3623 NG_NODE_REF(node); /* and one for the item */
3624 NGI_SET_NODE(item, node);
3625 if (hook) {
3626 NG_HOOK_REF(hook);
3627 NGI_SET_HOOK(item, hook);
3628 }
3629 NGI_FN(item) = fn;
3630 NGI_ARG1(item) = arg1;
3631 NGI_ARG2(item) = arg2;
3632 oitem = c->c_arg;
3633 if (callout_reset(c, ticks, &ng_callout_trampoline, item) == 1 &&
3634 oitem != NULL)
3635 NG_FREE_ITEM(oitem);
3636 return (0);
3637 }
3638
3639 /* A special modified version of untimeout() */
3640 int
3641 ng_uncallout(struct callout *c, node_p node)
3642 {
3643 item_p item;
3644 int rval;
3645
3646 KASSERT(c != NULL, ("ng_uncallout: NULL callout"));
3647 KASSERT(node != NULL, ("ng_uncallout: NULL node"));
3648
3649 rval = callout_stop(c);
3650 item = c->c_arg;
3651 /* Do an extra check */
3652 if ((rval > 0) && (c->c_func == &ng_callout_trampoline) &&
3653 (NGI_NODE(item) == node)) {
3654 /*
3655 * We successfully removed it from the queue before it ran
3656 * So now we need to unreference everything that was
3657 * given extra references. (NG_FREE_ITEM does this).
3658 */
3659 NG_FREE_ITEM(item);
3660 }
3661 c->c_arg = NULL;
3662
3663 return (rval);
3664 }
3665
3666 /*
3667 * Set the address, if none given, give the node here.
3668 */
3669 void
3670 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr)
3671 {
3672 if (retaddr) {
3673 NGI_RETADDR(item) = retaddr;
3674 } else {
3675 /*
3676 * The old return address should be ok.
3677 * If there isn't one, use the address here.
3678 */
3679 NGI_RETADDR(item) = ng_node2ID(here);
3680 }
3681 }
3682
3683 #define TESTING
3684 #ifdef TESTING
3685 /* just test all the macros */
3686 void
3687 ng_macro_test(item_p item);
3688 void
3689 ng_macro_test(item_p item)
3690 {
3691 node_p node = NULL;
3692 hook_p hook = NULL;
3693 struct mbuf *m;
3694 struct ng_mesg *msg;
3695 ng_ID_t retaddr;
3696 int error;
3697
3698 NGI_GET_M(item, m);
3699 NGI_GET_MSG(item, msg);
3700 retaddr = NGI_RETADDR(item);
3701 NG_SEND_DATA(error, hook, m, NULL);
3702 NG_SEND_DATA_ONLY(error, hook, m);
3703 NG_FWD_NEW_DATA(error, item, hook, m);
3704 NG_FWD_ITEM_HOOK(error, item, hook);
3705 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr);
3706 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr);
3707 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr);
3708 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr);
3709 }
3710 #endif /* TESTING */
3711
DragonFly BSD