kernel/netgraph7: Replace usage of MALLOC/FREE with kmalloc/kfree here too.
[dragonfly.git] / sys / netgraph7 / ng_base.c
CommitLineData
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1/*
2 * ng_base.c
3 */
4
5/*-
6 * Copyright (c) 1996-1999 Whistle Communications, Inc.
7 * All rights reserved.
8 *
9 * Subject to the following obligations and disclaimer of warranty, use and
10 * redistribution of this software, in source or object code forms, with or
11 * without modifications are expressly permitted by Whistle Communications;
12 * provided, however, that:
13 * 1. Any and all reproductions of the source or object code must include the
14 * copyright notice above and the following disclaimer of warranties; and
15 * 2. No rights are granted, in any manner or form, to use Whistle
16 * Communications, Inc. trademarks, including the mark "WHISTLE
17 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as
18 * such appears in the above copyright notice or in the software.
19 *
20 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
21 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
22 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
23 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
25 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
26 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
27 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
28 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
29 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
30 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
31 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
32 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
36 * OF SUCH DAMAGE.
37 *
38 * Authors: Julian Elischer <julian@freebsd.org>
39 * Archie Cobbs <archie@freebsd.org>
40 *
41 * $FreeBSD: src/sys/netgraph/ng_base.c,v 1.159 2008/04/19 05:30:49 mav Exp $
95af0087 42 * $DragonFly: src/sys/netgraph7/ng_base.c,v 1.4 2008/09/24 14:26:39 sephe Exp $
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43 * $Whistle: ng_base.c,v 1.39 1999/01/28 23:54:53 julian Exp $
44 */
45
46/*
47 * This file implements the base netgraph code.
48 */
49
50#include <sys/param.h>
51#include <sys/systm.h>
52#include <sys/ctype.h>
53#include <sys/errno.h>
5a975a3d 54/*#include <sys/kdb.h>*/
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55#include <sys/kernel.h>
56#include <sys/ktr.h>
57#include <sys/limits.h>
58#include <sys/malloc.h>
59#include <sys/mbuf.h>
60#include <sys/queue.h>
61#include <sys/sysctl.h>
62#include <sys/syslog.h>
63#include <sys/refcount.h>
64#include <sys/proc.h>
65#include <machine/cpu.h>
66
67#include <net/netisr.h>
68
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69#include "ng_message.h"
70#include "netgraph.h"
71#include "ng_parse.h"
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72
73MODULE_VERSION(netgraph, NG_ABI_VERSION);
74
75/* Mutex to protect topology events. */
76static struct mtx ng_topo_mtx;
77
78#ifdef NETGRAPH_DEBUG
79static struct mtx ng_nodelist_mtx; /* protects global node/hook lists */
80static struct mtx ngq_mtx; /* protects the queue item list */
81
82static SLIST_HEAD(, ng_node) ng_allnodes;
83static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */
84static SLIST_HEAD(, ng_hook) ng_allhooks;
85static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */
86
87static void ng_dumpitems(void);
88static void ng_dumpnodes(void);
89static void ng_dumphooks(void);
90
91#endif /* NETGRAPH_DEBUG */
92/*
93 * DEAD versions of the structures.
94 * In order to avoid races, it is sometimes neccesary to point
95 * at SOMETHING even though theoretically, the current entity is
96 * INVALID. Use these to avoid these races.
97 */
98struct ng_type ng_deadtype = {
99 NG_ABI_VERSION,
100 "dead",
101 NULL, /* modevent */
102 NULL, /* constructor */
103 NULL, /* rcvmsg */
104 NULL, /* shutdown */
105 NULL, /* newhook */
106 NULL, /* findhook */
107 NULL, /* connect */
108 NULL, /* rcvdata */
109 NULL, /* disconnect */
110 NULL, /* cmdlist */
111};
112
113struct ng_node ng_deadnode = {
114 "dead",
115 &ng_deadtype,
116 NGF_INVALID,
117 0, /* numhooks */
118 NULL, /* private */
119 0, /* ID */
120 LIST_HEAD_INITIALIZER(ng_deadnode.hooks),
121 {}, /* all_nodes list entry */
122 {}, /* id hashtable list entry */
123 { 0,
124 0,
125 {}, /* should never use! (should hang) */
126 {}, /* workqueue entry */
127 STAILQ_HEAD_INITIALIZER(ng_deadnode.nd_input_queue.queue),
128 },
129 1, /* refs */
130#ifdef NETGRAPH_DEBUG
131 ND_MAGIC,
132 __FILE__,
133 __LINE__,
134 {NULL}
135#endif /* NETGRAPH_DEBUG */
136};
137
138struct ng_hook ng_deadhook = {
139 "dead",
140 NULL, /* private */
141 HK_INVALID | HK_DEAD,
142 0, /* undefined data link type */
143 &ng_deadhook, /* Peer is self */
144 &ng_deadnode, /* attached to deadnode */
145 {}, /* hooks list */
146 NULL, /* override rcvmsg() */
147 NULL, /* override rcvdata() */
148 1, /* refs always >= 1 */
149#ifdef NETGRAPH_DEBUG
150 HK_MAGIC,
151 __FILE__,
152 __LINE__,
153 {NULL}
154#endif /* NETGRAPH_DEBUG */
155};
156
157/*
158 * END DEAD STRUCTURES
159 */
160/* List nodes with unallocated work */
161static STAILQ_HEAD(, ng_node) ng_worklist = STAILQ_HEAD_INITIALIZER(ng_worklist);
162static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */
163
164/* List of installed types */
165static LIST_HEAD(, ng_type) ng_typelist;
166static struct mtx ng_typelist_mtx;
167
168/* Hash related definitions */
169/* XXX Don't need to initialise them because it's a LIST */
170#define NG_ID_HASH_SIZE 128 /* most systems wont need even this many */
171static LIST_HEAD(, ng_node) ng_ID_hash[NG_ID_HASH_SIZE];
172static struct mtx ng_idhash_mtx;
173/* Method to find a node.. used twice so do it here */
174#define NG_IDHASH_FN(ID) ((ID) % (NG_ID_HASH_SIZE))
175#define NG_IDHASH_FIND(ID, node) \
176 do { \
177 mtx_assert(&ng_idhash_mtx, MA_OWNED); \
178 LIST_FOREACH(node, &ng_ID_hash[NG_IDHASH_FN(ID)], \
179 nd_idnodes) { \
180 if (NG_NODE_IS_VALID(node) \
181 && (NG_NODE_ID(node) == ID)) { \
182 break; \
183 } \
184 } \
185 } while (0)
186
187#define NG_NAME_HASH_SIZE 128 /* most systems wont need even this many */
188static LIST_HEAD(, ng_node) ng_name_hash[NG_NAME_HASH_SIZE];
189static struct mtx ng_namehash_mtx;
190#define NG_NAMEHASH(NAME, HASH) \
191 do { \
192 u_char h = 0; \
193 const u_char *c; \
194 for (c = (const u_char*)(NAME); *c; c++)\
195 h += *c; \
196 (HASH) = h % (NG_NAME_HASH_SIZE); \
197 } while (0)
198
199
200/* Internal functions */
201static int ng_add_hook(node_p node, const char *name, hook_p * hookp);
202static int ng_generic_msg(node_p here, item_p item, hook_p lasthook);
203static ng_ID_t ng_decodeidname(const char *name);
204static int ngb_mod_event(module_t mod, int event, void *data);
205static void ng_worklist_add(node_p node);
206static void ngintr(void);
207static int ng_apply_item(node_p node, item_p item, int rw);
208static void ng_flush_input_queue(node_p node);
209static node_p ng_ID2noderef(ng_ID_t ID);
210static int ng_con_nodes(item_p item, node_p node, const char *name,
211 node_p node2, const char *name2);
212static int ng_con_part2(node_p node, item_p item, hook_p hook);
213static int ng_con_part3(node_p node, item_p item, hook_p hook);
214static int ng_mkpeer(node_p node, const char *name,
215 const char *name2, char *type);
216
217/* Imported, these used to be externally visible, some may go back. */
218void ng_destroy_hook(hook_p hook);
219node_p ng_name2noderef(node_p node, const char *name);
220int ng_path2noderef(node_p here, const char *path,
221 node_p *dest, hook_p *lasthook);
222int ng_make_node(const char *type, node_p *nodepp);
223int ng_path_parse(char *addr, char **node, char **path, char **hook);
224void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3);
225void ng_unname(node_p node);
226
227
228/* Our own netgraph malloc type */
229MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages");
230MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures");
231MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures");
232MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", "netgraph item structures");
233MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage");
234
235/* Should not be visible outside this file */
236
237#define _NG_ALLOC_HOOK(hook) \
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238 hook = kmalloc(sizeof(*hook), M_NETGRAPH_HOOK, \
239 M_WAITOK | M_NULLOK | M_ZERO)
b06ebda0 240#define _NG_ALLOC_NODE(node) \
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241 node = kmalloc(sizeof(*node), M_NETGRAPH_NODE, \
242 M_WAITOK | M_NULLOK | M_ZERO)
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243
244#define NG_QUEUE_LOCK_INIT(n) \
245 mtx_init(&(n)->q_mtx, "ng_node", NULL, MTX_DEF)
246#define NG_QUEUE_LOCK(n) \
247 mtx_lock(&(n)->q_mtx)
248#define NG_QUEUE_UNLOCK(n) \
249 mtx_unlock(&(n)->q_mtx)
250#define NG_WORKLIST_LOCK_INIT() \
251 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_DEF)
252#define NG_WORKLIST_LOCK() \
253 mtx_lock(&ng_worklist_mtx)
254#define NG_WORKLIST_UNLOCK() \
255 mtx_unlock(&ng_worklist_mtx)
256
257#ifdef NETGRAPH_DEBUG /*----------------------------------------------*/
258/*
259 * In debug mode:
260 * In an attempt to help track reference count screwups
261 * we do not free objects back to the malloc system, but keep them
262 * in a local cache where we can examine them and keep information safely
263 * after they have been freed.
264 * We use this scheme for nodes and hooks, and to some extent for items.
265 */
266static __inline hook_p
267ng_alloc_hook(void)
268{
269 hook_p hook;
270 SLIST_ENTRY(ng_hook) temp;
271 mtx_lock(&ng_nodelist_mtx);
272 hook = LIST_FIRST(&ng_freehooks);
273 if (hook) {
274 LIST_REMOVE(hook, hk_hooks);
275 bcopy(&hook->hk_all, &temp, sizeof(temp));
276 bzero(hook, sizeof(struct ng_hook));
277 bcopy(&temp, &hook->hk_all, sizeof(temp));
278 mtx_unlock(&ng_nodelist_mtx);
279 hook->hk_magic = HK_MAGIC;
280 } else {
281 mtx_unlock(&ng_nodelist_mtx);
282 _NG_ALLOC_HOOK(hook);
283 if (hook) {
284 hook->hk_magic = HK_MAGIC;
285 mtx_lock(&ng_nodelist_mtx);
286 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all);
287 mtx_unlock(&ng_nodelist_mtx);
288 }
289 }
290 return (hook);
291}
292
293static __inline node_p
294ng_alloc_node(void)
295{
296 node_p node;
297 SLIST_ENTRY(ng_node) temp;
298 mtx_lock(&ng_nodelist_mtx);
299 node = LIST_FIRST(&ng_freenodes);
300 if (node) {
301 LIST_REMOVE(node, nd_nodes);
302 bcopy(&node->nd_all, &temp, sizeof(temp));
303 bzero(node, sizeof(struct ng_node));
304 bcopy(&temp, &node->nd_all, sizeof(temp));
305 mtx_unlock(&ng_nodelist_mtx);
306 node->nd_magic = ND_MAGIC;
307 } else {
308 mtx_unlock(&ng_nodelist_mtx);
309 _NG_ALLOC_NODE(node);
310 if (node) {
311 node->nd_magic = ND_MAGIC;
312 mtx_lock(&ng_nodelist_mtx);
313 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all);
314 mtx_unlock(&ng_nodelist_mtx);
315 }
316 }
317 return (node);
318}
319
320#define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0)
321#define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0)
322
323
324#define NG_FREE_HOOK(hook) \
325 do { \
326 mtx_lock(&ng_nodelist_mtx); \
327 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \
328 hook->hk_magic = 0; \
329 mtx_unlock(&ng_nodelist_mtx); \
330 } while (0)
331
332#define NG_FREE_NODE(node) \
333 do { \
334 mtx_lock(&ng_nodelist_mtx); \
335 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \
336 node->nd_magic = 0; \
337 mtx_unlock(&ng_nodelist_mtx); \
338 } while (0)
339
340#else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
341
342#define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook)
343#define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node)
344
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345#define NG_FREE_HOOK(hook) do { kfree((hook), M_NETGRAPH_HOOK); } while (0)
346#define NG_FREE_NODE(node) do { kfree((node), M_NETGRAPH_NODE); } while (0)
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347
348#endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
349
350/* Set this to kdb_enter("X") to catch all errors as they occur */
351#ifndef TRAP_ERROR
352#define TRAP_ERROR()
353#endif
354
355static ng_ID_t nextID = 1;
356
357#ifdef INVARIANTS
358#define CHECK_DATA_MBUF(m) do { \
359 struct mbuf *n; \
360 int total; \
361 \
362 M_ASSERTPKTHDR(m); \
363 for (total = 0, n = (m); n != NULL; n = n->m_next) { \
364 total += n->m_len; \
365 if (n->m_nextpkt != NULL) \
366 panic("%s: m_nextpkt", __func__); \
367 } \
368 \
369 if ((m)->m_pkthdr.len != total) { \
370 panic("%s: %d != %d", \
371 __func__, (m)->m_pkthdr.len, total); \
372 } \
373 } while (0)
374#else
375#define CHECK_DATA_MBUF(m)
376#endif
377
378#define ERROUT(x) do { error = (x); goto done; } while (0)
379
380/************************************************************************
381 Parse type definitions for generic messages
382************************************************************************/
383
384/* Handy structure parse type defining macro */
385#define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \
386static const struct ng_parse_struct_field \
387 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \
388static const struct ng_parse_type ng_generic_ ## lo ## _type = { \
389 &ng_parse_struct_type, \
390 &ng_ ## lo ## _type_fields \
391}
392
393DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ());
394DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ());
395DEFINE_PARSE_STRUCT_TYPE(name, NAME, ());
396DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ());
397DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ());
398DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ());
399DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type));
400
401/* Get length of an array when the length is stored as a 32 bit
402 value immediately preceding the array -- as with struct namelist
403 and struct typelist. */
404static int
405ng_generic_list_getLength(const struct ng_parse_type *type,
406 const u_char *start, const u_char *buf)
407{
408 return *((const u_int32_t *)(buf - 4));
409}
410
411/* Get length of the array of struct linkinfo inside a struct hooklist */
412static int
413ng_generic_linkinfo_getLength(const struct ng_parse_type *type,
414 const u_char *start, const u_char *buf)
415{
416 const struct hooklist *hl = (const struct hooklist *)start;
417
418 return hl->nodeinfo.hooks;
419}
420
421/* Array type for a variable length array of struct namelist */
422static const struct ng_parse_array_info ng_nodeinfoarray_type_info = {
423 &ng_generic_nodeinfo_type,
424 &ng_generic_list_getLength
425};
426static const struct ng_parse_type ng_generic_nodeinfoarray_type = {
427 &ng_parse_array_type,
428 &ng_nodeinfoarray_type_info
429};
430
431/* Array type for a variable length array of struct typelist */
432static const struct ng_parse_array_info ng_typeinfoarray_type_info = {
433 &ng_generic_typeinfo_type,
434 &ng_generic_list_getLength
435};
436static const struct ng_parse_type ng_generic_typeinfoarray_type = {
437 &ng_parse_array_type,
438 &ng_typeinfoarray_type_info
439};
440
441/* Array type for array of struct linkinfo in struct hooklist */
442static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = {
443 &ng_generic_linkinfo_type,
444 &ng_generic_linkinfo_getLength
445};
446static const struct ng_parse_type ng_generic_linkinfo_array_type = {
447 &ng_parse_array_type,
448 &ng_generic_linkinfo_array_type_info
449};
450
451DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type));
452DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST,
453 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type));
454DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES,
455 (&ng_generic_nodeinfoarray_type));
456
457/* List of commands and how to convert arguments to/from ASCII */
458static const struct ng_cmdlist ng_generic_cmds[] = {
459 {
460 NGM_GENERIC_COOKIE,
461 NGM_SHUTDOWN,
462 "shutdown",
463 NULL,
464 NULL
465 },
466 {
467 NGM_GENERIC_COOKIE,
468 NGM_MKPEER,
469 "mkpeer",
470 &ng_generic_mkpeer_type,
471 NULL
472 },
473 {
474 NGM_GENERIC_COOKIE,
475 NGM_CONNECT,
476 "connect",
477 &ng_generic_connect_type,
478 NULL
479 },
480 {
481 NGM_GENERIC_COOKIE,
482 NGM_NAME,
483 "name",
484 &ng_generic_name_type,
485 NULL
486 },
487 {
488 NGM_GENERIC_COOKIE,
489 NGM_RMHOOK,
490 "rmhook",
491 &ng_generic_rmhook_type,
492 NULL
493 },
494 {
495 NGM_GENERIC_COOKIE,
496 NGM_NODEINFO,
497 "nodeinfo",
498 NULL,
499 &ng_generic_nodeinfo_type
500 },
501 {
502 NGM_GENERIC_COOKIE,
503 NGM_LISTHOOKS,
504 "listhooks",
505 NULL,
506 &ng_generic_hooklist_type
507 },
508 {
509 NGM_GENERIC_COOKIE,
510 NGM_LISTNAMES,
511 "listnames",
512 NULL,
513 &ng_generic_listnodes_type /* same as NGM_LISTNODES */
514 },
515 {
516 NGM_GENERIC_COOKIE,
517 NGM_LISTNODES,
518 "listnodes",
519 NULL,
520 &ng_generic_listnodes_type
521 },
522 {
523 NGM_GENERIC_COOKIE,
524 NGM_LISTTYPES,
525 "listtypes",
526 NULL,
527 &ng_generic_typeinfo_type
528 },
529 {
530 NGM_GENERIC_COOKIE,
531 NGM_TEXT_CONFIG,
532 "textconfig",
533 NULL,
534 &ng_parse_string_type
535 },
536 {
537 NGM_GENERIC_COOKIE,
538 NGM_TEXT_STATUS,
539 "textstatus",
540 NULL,
541 &ng_parse_string_type
542 },
543 {
544 NGM_GENERIC_COOKIE,
545 NGM_ASCII2BINARY,
546 "ascii2binary",
547 &ng_parse_ng_mesg_type,
548 &ng_parse_ng_mesg_type
549 },
550 {
551 NGM_GENERIC_COOKIE,
552 NGM_BINARY2ASCII,
553 "binary2ascii",
554 &ng_parse_ng_mesg_type,
555 &ng_parse_ng_mesg_type
556 },
557 { 0 }
558};
559
560/************************************************************************
561 Node routines
562************************************************************************/
563
564/*
565 * Instantiate a node of the requested type
566 */
567int
568ng_make_node(const char *typename, node_p *nodepp)
569{
570 struct ng_type *type;
571 int error;
572
573 /* Check that the type makes sense */
574 if (typename == NULL) {
575 TRAP_ERROR();
576 return (EINVAL);
577 }
578
579 /* Locate the node type. If we fail we return. Do not try to load
580 * module.
581 */
582 if ((type = ng_findtype(typename)) == NULL)
583 return (ENXIO);
584
585 /*
586 * If we have a constructor, then make the node and
587 * call the constructor to do type specific initialisation.
588 */
589 if (type->constructor != NULL) {
590 if ((error = ng_make_node_common(type, nodepp)) == 0) {
591 if ((error = ((*type->constructor)(*nodepp)) != 0)) {
592 NG_NODE_UNREF(*nodepp);
593 }
594 }
595 } else {
596 /*
597 * Node has no constructor. We cannot ask for one
598 * to be made. It must be brought into existence by
599 * some external agency. The external agency should
600 * call ng_make_node_common() directly to get the
601 * netgraph part initialised.
602 */
603 TRAP_ERROR();
604 error = EINVAL;
605 }
606 return (error);
607}
608
609/*
610 * Generic node creation. Called by node initialisation for externally
611 * instantiated nodes (e.g. hardware, sockets, etc ).
612 * The returned node has a reference count of 1.
613 */
614int
615ng_make_node_common(struct ng_type *type, node_p *nodepp)
616{
617 node_p node;
618
619 /* Require the node type to have been already installed */
620 if (ng_findtype(type->name) == NULL) {
621 TRAP_ERROR();
622 return (EINVAL);
623 }
624
625 /* Make a node and try attach it to the type */
626 NG_ALLOC_NODE(node);
627 if (node == NULL) {
628 TRAP_ERROR();
629 return (ENOMEM);
630 }
631 node->nd_type = type;
632 NG_NODE_REF(node); /* note reference */
633 type->refs++;
634
635 NG_QUEUE_LOCK_INIT(&node->nd_input_queue);
636 STAILQ_INIT(&node->nd_input_queue.queue);
637 node->nd_input_queue.q_flags = 0;
638
639 /* Initialize hook list for new node */
640 LIST_INIT(&node->nd_hooks);
641
642 /* Link us into the name hash. */
643 mtx_lock(&ng_namehash_mtx);
644 LIST_INSERT_HEAD(&ng_name_hash[0], node, nd_nodes);
645 mtx_unlock(&ng_namehash_mtx);
646
647 /* get an ID and put us in the hash chain */
648 mtx_lock(&ng_idhash_mtx);
649 for (;;) { /* wrap protection, even if silly */
650 node_p node2 = NULL;
651 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */
652
653 /* Is there a problem with the new number? */
654 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */
655 if ((node->nd_ID != 0) && (node2 == NULL)) {
656 break;
657 }
658 }
659 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)],
660 node, nd_idnodes);
661 mtx_unlock(&ng_idhash_mtx);
662
663 /* Done */
664 *nodepp = node;
665 return (0);
666}
667
668/*
669 * Forceably start the shutdown process on a node. Either call
670 * its shutdown method, or do the default shutdown if there is
671 * no type-specific method.
672 *
673 * We can only be called from a shutdown message, so we know we have
674 * a writer lock, and therefore exclusive access. It also means
675 * that we should not be on the work queue, but we check anyhow.
676 *
677 * Persistent node types must have a type-specific method which
678 * allocates a new node in which case, this one is irretrievably going away,
679 * or cleans up anything it needs, and just makes the node valid again,
680 * in which case we allow the node to survive.
681 *
682 * XXX We need to think of how to tell a persistent node that we
683 * REALLY need to go away because the hardware has gone or we
684 * are rebooting.... etc.
685 */
686void
687ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3)
688{
689 hook_p hook;
690
691 /* Check if it's already shutting down */
692 if ((node->nd_flags & NGF_CLOSING) != 0)
693 return;
694
695 if (node == &ng_deadnode) {
696 printf ("shutdown called on deadnode\n");
697 return;
698 }
699
700 /* Add an extra reference so it doesn't go away during this */
701 NG_NODE_REF(node);
702
703 /*
704 * Mark it invalid so any newcomers know not to try use it
705 * Also add our own mark so we can't recurse
706 * note that NGF_INVALID does not do this as it's also set during
707 * creation
708 */
709 node->nd_flags |= NGF_INVALID|NGF_CLOSING;
710
711 /* If node has its pre-shutdown method, then call it first*/
712 if (node->nd_type && node->nd_type->close)
713 (*node->nd_type->close)(node);
714
715 /* Notify all remaining connected nodes to disconnect */
716 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL)
717 ng_destroy_hook(hook);
718
719 /*
720 * Drain the input queue forceably.
721 * it has no hooks so what's it going to do, bleed on someone?
722 * Theoretically we came here from a queue entry that was added
723 * Just before the queue was closed, so it should be empty anyway.
724 * Also removes us from worklist if needed.
725 */
726 ng_flush_input_queue(node);
727
728 /* Ask the type if it has anything to do in this case */
729 if (node->nd_type && node->nd_type->shutdown) {
730 (*node->nd_type->shutdown)(node);
731 if (NG_NODE_IS_VALID(node)) {
732 /*
733 * Well, blow me down if the node code hasn't declared
734 * that it doesn't want to die.
735 * Presumably it is a persistant node.
736 * If we REALLY want it to go away,
737 * e.g. hardware going away,
738 * Our caller should set NGF_REALLY_DIE in nd_flags.
739 */
740 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING);
741 NG_NODE_UNREF(node); /* Assume they still have theirs */
742 return;
743 }
744 } else { /* do the default thing */
745 NG_NODE_UNREF(node);
746 }
747
748 ng_unname(node); /* basically a NOP these days */
749
750 /*
751 * Remove extra reference, possibly the last
752 * Possible other holders of references may include
753 * timeout callouts, but theoretically the node's supposed to
754 * have cancelled them. Possibly hardware dependencies may
755 * force a driver to 'linger' with a reference.
756 */
757 NG_NODE_UNREF(node);
758}
759
760/*
761 * Remove a reference to the node, possibly the last.
762 * deadnode always acts as it it were the last.
763 */
764int
765ng_unref_node(node_p node)
766{
767 int v;
768
769 if (node == &ng_deadnode) {
770 return (0);
771 }
772
773 v = atomic_fetchadd_int(&node->nd_refs, -1);
774
775 if (v == 1) { /* we were the last */
776
777 mtx_lock(&ng_namehash_mtx);
778 node->nd_type->refs--; /* XXX maybe should get types lock? */
779 LIST_REMOVE(node, nd_nodes);
780 mtx_unlock(&ng_namehash_mtx);
781
782 mtx_lock(&ng_idhash_mtx);
783 LIST_REMOVE(node, nd_idnodes);
784 mtx_unlock(&ng_idhash_mtx);
785
786 mtx_destroy(&node->nd_input_queue.q_mtx);
787 NG_FREE_NODE(node);
788 }
789 return (v - 1);
790}
791
792/************************************************************************
793 Node ID handling
794************************************************************************/
795static node_p
796ng_ID2noderef(ng_ID_t ID)
797{
798 node_p node;
799 mtx_lock(&ng_idhash_mtx);
800 NG_IDHASH_FIND(ID, node);
801 if(node)
802 NG_NODE_REF(node);
803 mtx_unlock(&ng_idhash_mtx);
804 return(node);
805}
806
807ng_ID_t
808ng_node2ID(node_p node)
809{
810 return (node ? NG_NODE_ID(node) : 0);
811}
812
813/************************************************************************
814 Node name handling
815************************************************************************/
816
817/*
818 * Assign a node a name. Once assigned, the name cannot be changed.
819 */
820int
821ng_name_node(node_p node, const char *name)
822{
823 int i, hash;
824 node_p node2;
825
826 /* Check the name is valid */
827 for (i = 0; i < NG_NODESIZ; i++) {
828 if (name[i] == '\0' || name[i] == '.' || name[i] == ':')
829 break;
830 }
831 if (i == 0 || name[i] != '\0') {
832 TRAP_ERROR();
833 return (EINVAL);
834 }
835 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */
836 TRAP_ERROR();
837 return (EINVAL);
838 }
839
840 /* Check the name isn't already being used */
841 if ((node2 = ng_name2noderef(node, name)) != NULL) {
842 NG_NODE_UNREF(node2);
843 TRAP_ERROR();
844 return (EADDRINUSE);
845 }
846
847 /* copy it */
848 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ);
849
850 /* Update name hash. */
851 NG_NAMEHASH(name, hash);
852 mtx_lock(&ng_namehash_mtx);
853 LIST_REMOVE(node, nd_nodes);
854 LIST_INSERT_HEAD(&ng_name_hash[hash], node, nd_nodes);
855 mtx_unlock(&ng_namehash_mtx);
856
857 return (0);
858}
859
860/*
861 * Find a node by absolute name. The name should NOT end with ':'
862 * The name "." means "this node" and "[xxx]" means "the node
863 * with ID (ie, at address) xxx".
864 *
865 * Returns the node if found, else NULL.
866 * Eventually should add something faster than a sequential search.
867 * Note it acquires a reference on the node so you can be sure it's still
868 * there.
869 */
870node_p
871ng_name2noderef(node_p here, const char *name)
872{
873 node_p node;
874 ng_ID_t temp;
875 int hash;
876
877 /* "." means "this node" */
878 if (strcmp(name, ".") == 0) {
879 NG_NODE_REF(here);
880 return(here);
881 }
882
883 /* Check for name-by-ID */
884 if ((temp = ng_decodeidname(name)) != 0) {
885 return (ng_ID2noderef(temp));
886 }
887
888 /* Find node by name */
889 NG_NAMEHASH(name, hash);
890 mtx_lock(&ng_namehash_mtx);
891 LIST_FOREACH(node, &ng_name_hash[hash], nd_nodes) {
892 if (NG_NODE_IS_VALID(node) &&
893 (strcmp(NG_NODE_NAME(node), name) == 0)) {
894 break;
895 }
896 }
897 if (node)
898 NG_NODE_REF(node);
899 mtx_unlock(&ng_namehash_mtx);
900 return (node);
901}
902
903/*
904 * Decode an ID name, eg. "[f03034de]". Returns 0 if the
905 * string is not valid, otherwise returns the value.
906 */
907static ng_ID_t
908ng_decodeidname(const char *name)
909{
910 const int len = strlen(name);
911 char *eptr;
912 u_long val;
913
914 /* Check for proper length, brackets, no leading junk */
915 if ((len < 3)
916 || (name[0] != '[')
917 || (name[len - 1] != ']')
918 || (!isxdigit(name[1]))) {
919 return ((ng_ID_t)0);
920 }
921
922 /* Decode number */
923 val = strtoul(name + 1, &eptr, 16);
924 if ((eptr - name != len - 1)
925 || (val == ULONG_MAX)
926 || (val == 0)) {
927 return ((ng_ID_t)0);
928 }
929 return (ng_ID_t)val;
930}
931
932/*
933 * Remove a name from a node. This should only be called
934 * when shutting down and removing the node.
935 * IF we allow name changing this may be more resurrected.
936 */
937void
938ng_unname(node_p node)
939{
940}
941
942/************************************************************************
943 Hook routines
944 Names are not optional. Hooks are always connected, except for a
945 brief moment within these routines. On invalidation or during creation
946 they are connected to the 'dead' hook.
947************************************************************************/
948
949/*
950 * Remove a hook reference
951 */
952void
953ng_unref_hook(hook_p hook)
954{
955 int v;
956
957 if (hook == &ng_deadhook) {
958 return;
959 }
960
961 v = atomic_fetchadd_int(&hook->hk_refs, -1);
962
963 if (v == 1) { /* we were the last */
964 if (_NG_HOOK_NODE(hook)) /* it'll probably be ng_deadnode */
965 _NG_NODE_UNREF((_NG_HOOK_NODE(hook)));
966 NG_FREE_HOOK(hook);
967 }
968}
969
970/*
971 * Add an unconnected hook to a node. Only used internally.
972 * Assumes node is locked. (XXX not yet true )
973 */
974static int
975ng_add_hook(node_p node, const char *name, hook_p *hookp)
976{
977 hook_p hook;
978 int error = 0;
979
980 /* Check that the given name is good */
981 if (name == NULL) {
982 TRAP_ERROR();
983 return (EINVAL);
984 }
985 if (ng_findhook(node, name) != NULL) {
986 TRAP_ERROR();
987 return (EEXIST);
988 }
989
990 /* Allocate the hook and link it up */
991 NG_ALLOC_HOOK(hook);
992 if (hook == NULL) {
993 TRAP_ERROR();
994 return (ENOMEM);
995 }
996 hook->hk_refs = 1; /* add a reference for us to return */
997 hook->hk_flags = HK_INVALID;
998 hook->hk_peer = &ng_deadhook; /* start off this way */
999 hook->hk_node = node;
1000 NG_NODE_REF(node); /* each hook counts as a reference */
1001
1002 /* Set hook name */
1003 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ);
1004
1005 /*
1006 * Check if the node type code has something to say about it
1007 * If it fails, the unref of the hook will also unref the node.
1008 */
1009 if (node->nd_type->newhook != NULL) {
1010 if ((error = (*node->nd_type->newhook)(node, hook, name))) {
1011 NG_HOOK_UNREF(hook); /* this frees the hook */
1012 return (error);
1013 }
1014 }
1015 /*
1016 * The 'type' agrees so far, so go ahead and link it in.
1017 * We'll ask again later when we actually connect the hooks.
1018 */
1019 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
1020 node->nd_numhooks++;
1021 NG_HOOK_REF(hook); /* one for the node */
1022
1023 if (hookp)
1024 *hookp = hook;
1025 return (0);
1026}
1027
1028/*
1029 * Find a hook
1030 *
1031 * Node types may supply their own optimized routines for finding
1032 * hooks. If none is supplied, we just do a linear search.
1033 * XXX Possibly we should add a reference to the hook?
1034 */
1035hook_p
1036ng_findhook(node_p node, const char *name)
1037{
1038 hook_p hook;
1039
1040 if (node->nd_type->findhook != NULL)
1041 return (*node->nd_type->findhook)(node, name);
1042 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
1043 if (NG_HOOK_IS_VALID(hook)
1044 && (strcmp(NG_HOOK_NAME(hook), name) == 0))
1045 return (hook);
1046 }
1047 return (NULL);
1048}
1049
1050/*
1051 * Destroy a hook
1052 *
1053 * As hooks are always attached, this really destroys two hooks.
1054 * The one given, and the one attached to it. Disconnect the hooks
1055 * from each other first. We reconnect the peer hook to the 'dead'
1056 * hook so that it can still exist after we depart. We then
1057 * send the peer its own destroy message. This ensures that we only
1058 * interact with the peer's structures when it is locked processing that
1059 * message. We hold a reference to the peer hook so we are guaranteed that
1060 * the peer hook and node are still going to exist until
1061 * we are finished there as the hook holds a ref on the node.
1062 * We run this same code again on the peer hook, but that time it is already
1063 * attached to the 'dead' hook.
1064 *
1065 * This routine is called at all stages of hook creation
1066 * on error detection and must be able to handle any such stage.
1067 */
1068void
1069ng_destroy_hook(hook_p hook)
1070{
1071 hook_p peer;
1072 node_p node;
1073
1074 if (hook == &ng_deadhook) { /* better safe than sorry */
1075 printf("ng_destroy_hook called on deadhook\n");
1076 return;
1077 }
1078
1079 /*
1080 * Protect divorce process with mutex, to avoid races on
1081 * simultaneous disconnect.
1082 */
1083 mtx_lock(&ng_topo_mtx);
1084
1085 hook->hk_flags |= HK_INVALID;
1086
1087 peer = NG_HOOK_PEER(hook);
1088 node = NG_HOOK_NODE(hook);
1089
1090 if (peer && (peer != &ng_deadhook)) {
1091 /*
1092 * Set the peer to point to ng_deadhook
1093 * from this moment on we are effectively independent it.
1094 * send it an rmhook message of it's own.
1095 */
1096 peer->hk_peer = &ng_deadhook; /* They no longer know us */
1097 hook->hk_peer = &ng_deadhook; /* Nor us, them */
1098 if (NG_HOOK_NODE(peer) == &ng_deadnode) {
1099 /*
1100 * If it's already divorced from a node,
1101 * just free it.
1102 */
1103 mtx_unlock(&ng_topo_mtx);
1104 } else {
1105 mtx_unlock(&ng_topo_mtx);
1106 ng_rmhook_self(peer); /* Send it a surprise */
1107 }
1108 NG_HOOK_UNREF(peer); /* account for peer link */
1109 NG_HOOK_UNREF(hook); /* account for peer link */
1110 } else
1111 mtx_unlock(&ng_topo_mtx);
1112
1113 mtx_assert(&ng_topo_mtx, MA_NOTOWNED);
1114
1115 /*
1116 * Remove the hook from the node's list to avoid possible recursion
1117 * in case the disconnection results in node shutdown.
1118 */
1119 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */
1120 return;
1121 }
1122 LIST_REMOVE(hook, hk_hooks);
1123 node->nd_numhooks--;
1124 if (node->nd_type->disconnect) {
1125 /*
1126 * The type handler may elect to destroy the node so don't
1127 * trust its existence after this point. (except
1128 * that we still hold a reference on it. (which we
1129 * inherrited from the hook we are destroying)
1130 */
1131 (*node->nd_type->disconnect) (hook);
1132 }
1133
1134 /*
1135 * Note that because we will point to ng_deadnode, the original node
1136 * is not decremented automatically so we do that manually.
1137 */
1138 _NG_HOOK_NODE(hook) = &ng_deadnode;
1139 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */
1140 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */
1141}
1142
1143/*
1144 * Take two hooks on a node and merge the connection so that the given node
1145 * is effectively bypassed.
1146 */
1147int
1148ng_bypass(hook_p hook1, hook_p hook2)
1149{
1150 if (hook1->hk_node != hook2->hk_node) {
1151 TRAP_ERROR();
1152 return (EINVAL);
1153 }
1154 hook1->hk_peer->hk_peer = hook2->hk_peer;
1155 hook2->hk_peer->hk_peer = hook1->hk_peer;
1156
1157 hook1->hk_peer = &ng_deadhook;
1158 hook2->hk_peer = &ng_deadhook;
1159
1160 NG_HOOK_UNREF(hook1);
1161 NG_HOOK_UNREF(hook2);
1162
1163 /* XXX If we ever cache methods on hooks update them as well */
1164 ng_destroy_hook(hook1);
1165 ng_destroy_hook(hook2);
1166 return (0);
1167}
1168
1169/*
1170 * Install a new netgraph type
1171 */
1172int
1173ng_newtype(struct ng_type *tp)
1174{
1175 const size_t namelen = strlen(tp->name);
1176
1177 /* Check version and type name fields */
1178 if ((tp->version != NG_ABI_VERSION)
1179 || (namelen == 0)
1180 || (namelen >= NG_TYPESIZ)) {
1181 TRAP_ERROR();
1182 if (tp->version != NG_ABI_VERSION) {
1183 printf("Netgraph: Node type rejected. ABI mismatch. Suggest recompile\n");
1184 }
1185 return (EINVAL);
1186 }
1187
1188 /* Check for name collision */
1189 if (ng_findtype(tp->name) != NULL) {
1190 TRAP_ERROR();
1191 return (EEXIST);
1192 }
1193
1194
1195 /* Link in new type */
1196 mtx_lock(&ng_typelist_mtx);
1197 LIST_INSERT_HEAD(&ng_typelist, tp, types);
1198 tp->refs = 1; /* first ref is linked list */
1199 mtx_unlock(&ng_typelist_mtx);
1200 return (0);
1201}
1202
1203/*
1204 * unlink a netgraph type
1205 * If no examples exist
1206 */
1207int
1208ng_rmtype(struct ng_type *tp)
1209{
1210 /* Check for name collision */
1211 if (tp->refs != 1) {
1212 TRAP_ERROR();
1213 return (EBUSY);
1214 }
1215
1216 /* Unlink type */
1217 mtx_lock(&ng_typelist_mtx);
1218 LIST_REMOVE(tp, types);
1219 mtx_unlock(&ng_typelist_mtx);
1220 return (0);
1221}
1222
1223/*
1224 * Look for a type of the name given
1225 */
1226struct ng_type *
1227ng_findtype(const char *typename)
1228{
1229 struct ng_type *type;
1230
1231 mtx_lock(&ng_typelist_mtx);
1232 LIST_FOREACH(type, &ng_typelist, types) {
1233 if (strcmp(type->name, typename) == 0)
1234 break;
1235 }
1236 mtx_unlock(&ng_typelist_mtx);
1237 return (type);
1238}
1239
1240/************************************************************************
1241 Composite routines
1242************************************************************************/
1243/*
1244 * Connect two nodes using the specified hooks, using queued functions.
1245 */
1246static int
1247ng_con_part3(node_p node, item_p item, hook_p hook)
1248{
1249 int error = 0;
1250
1251 /*
1252 * When we run, we know that the node 'node' is locked for us.
1253 * Our caller has a reference on the hook.
1254 * Our caller has a reference on the node.
1255 * (In this case our caller is ng_apply_item() ).
1256 * The peer hook has a reference on the hook.
1257 * We are all set up except for the final call to the node, and
1258 * the clearing of the INVALID flag.
1259 */
1260 if (NG_HOOK_NODE(hook) == &ng_deadnode) {
1261 /*
1262 * The node must have been freed again since we last visited
1263 * here. ng_destry_hook() has this effect but nothing else does.
1264 * We should just release our references and
1265 * free anything we can think of.
1266 * Since we know it's been destroyed, and it's our caller
1267 * that holds the references, just return.
1268 */
1269 ERROUT(ENOENT);
1270 }
1271 if (hook->hk_node->nd_type->connect) {
1272 if ((error = (*hook->hk_node->nd_type->connect) (hook))) {
1273 ng_destroy_hook(hook); /* also zaps peer */
1274 printf("failed in ng_con_part3()\n");
1275 ERROUT(error);
1276 }
1277 }
1278 /*
1279 * XXX this is wrong for SMP. Possibly we need
1280 * to separate out 'create' and 'invalid' flags.
1281 * should only set flags on hooks we have locked under our node.
1282 */
1283 hook->hk_flags &= ~HK_INVALID;
1284done:
1285 NG_FREE_ITEM(item);
1286 return (error);
1287}
1288
1289static int
1290ng_con_part2(node_p node, item_p item, hook_p hook)
1291{
1292 hook_p peer;
1293 int error = 0;
1294
1295 /*
1296 * When we run, we know that the node 'node' is locked for us.
1297 * Our caller has a reference on the hook.
1298 * Our caller has a reference on the node.
1299 * (In this case our caller is ng_apply_item() ).
1300 * The peer hook has a reference on the hook.
1301 * our node pointer points to the 'dead' node.
1302 * First check the hook name is unique.
1303 * Should not happen because we checked before queueing this.
1304 */
1305 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) {
1306 TRAP_ERROR();
1307 ng_destroy_hook(hook); /* should destroy peer too */
1308 printf("failed in ng_con_part2()\n");
1309 ERROUT(EEXIST);
1310 }
1311 /*
1312 * Check if the node type code has something to say about it
1313 * If it fails, the unref of the hook will also unref the attached node,
1314 * however since that node is 'ng_deadnode' this will do nothing.
1315 * The peer hook will also be destroyed.
1316 */
1317 if (node->nd_type->newhook != NULL) {
1318 if ((error = (*node->nd_type->newhook)(node, hook,
1319 hook->hk_name))) {
1320 ng_destroy_hook(hook); /* should destroy peer too */
1321 printf("failed in ng_con_part2()\n");
1322 ERROUT(error);
1323 }
1324 }
1325
1326 /*
1327 * The 'type' agrees so far, so go ahead and link it in.
1328 * We'll ask again later when we actually connect the hooks.
1329 */
1330 hook->hk_node = node; /* just overwrite ng_deadnode */
1331 NG_NODE_REF(node); /* each hook counts as a reference */
1332 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
1333 node->nd_numhooks++;
1334 NG_HOOK_REF(hook); /* one for the node */
1335
1336 /*
1337 * We now have a symmetrical situation, where both hooks have been
1338 * linked to their nodes, the newhook methods have been called
1339 * And the references are all correct. The hooks are still marked
1340 * as invalid, as we have not called the 'connect' methods
1341 * yet.
1342 * We can call the local one immediately as we have the
1343 * node locked, but we need to queue the remote one.
1344 */
1345 if (hook->hk_node->nd_type->connect) {
1346 if ((error = (*hook->hk_node->nd_type->connect) (hook))) {
1347 ng_destroy_hook(hook); /* also zaps peer */
1348 printf("failed in ng_con_part2(A)\n");
1349 ERROUT(error);
1350 }
1351 }
1352
1353 /*
1354 * Acquire topo mutex to avoid race with ng_destroy_hook().
1355 */
1356 mtx_lock(&ng_topo_mtx);
1357 peer = hook->hk_peer;
1358 if (peer == &ng_deadhook) {
1359 mtx_unlock(&ng_topo_mtx);
1360 printf("failed in ng_con_part2(B)\n");
1361 ng_destroy_hook(hook);
1362 ERROUT(ENOENT);
1363 }
1364 mtx_unlock(&ng_topo_mtx);
1365
1366 if ((error = ng_send_fn2(peer->hk_node, peer, item, &ng_con_part3,
1367 NULL, 0, NG_REUSE_ITEM))) {
1368 printf("failed in ng_con_part2(C)\n");
1369 ng_destroy_hook(hook); /* also zaps peer */
1370 return (error); /* item was consumed. */
1371 }
1372 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */
1373 return (0); /* item was consumed. */
1374done:
1375 NG_FREE_ITEM(item);
1376 return (error);
1377}
1378
1379/*
1380 * Connect this node with another node. We assume that this node is
1381 * currently locked, as we are only called from an NGM_CONNECT message.
1382 */
1383static int
1384ng_con_nodes(item_p item, node_p node, const char *name,
1385 node_p node2, const char *name2)
1386{
1387 int error;
1388 hook_p hook;
1389 hook_p hook2;
1390
1391 if (ng_findhook(node2, name2) != NULL) {
1392 return(EEXIST);
1393 }
1394 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */
1395 return (error);
1396 /* Allocate the other hook and link it up */
1397 NG_ALLOC_HOOK(hook2);
1398 if (hook2 == NULL) {
1399 TRAP_ERROR();
1400 ng_destroy_hook(hook); /* XXX check ref counts so far */
1401 NG_HOOK_UNREF(hook); /* including our ref */
1402 return (ENOMEM);
1403 }
1404 hook2->hk_refs = 1; /* start with a reference for us. */
1405 hook2->hk_flags = HK_INVALID;
1406 hook2->hk_peer = hook; /* Link the two together */
1407 hook->hk_peer = hook2;
1408 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/
1409 NG_HOOK_REF(hook2);
1410 hook2->hk_node = &ng_deadnode;
1411 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ);
1412
1413 /*
1414 * Queue the function above.
1415 * Procesing continues in that function in the lock context of
1416 * the other node.
1417 */
1418 if ((error = ng_send_fn2(node2, hook2, item, &ng_con_part2, NULL, 0,
1419 NG_NOFLAGS))) {
1420 printf("failed in ng_con_nodes(): %d\n", error);
1421 ng_destroy_hook(hook); /* also zaps peer */
1422 }
1423
1424 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */
1425 NG_HOOK_UNREF(hook2);
1426 return (error);
1427}
1428
1429/*
1430 * Make a peer and connect.
1431 * We assume that the local node is locked.
1432 * The new node probably doesn't need a lock until
1433 * it has a hook, because it cannot really have any work until then,
1434 * but we should think about it a bit more.
1435 *
1436 * The problem may come if the other node also fires up
1437 * some hardware or a timer or some other source of activation,
1438 * also it may already get a command msg via it's ID.
1439 *
1440 * We could use the same method as ng_con_nodes() but we'd have
1441 * to add ability to remove the node when failing. (Not hard, just
1442 * make arg1 point to the node to remove).
1443 * Unless of course we just ignore failure to connect and leave
1444 * an unconnected node?
1445 */
1446static int
1447ng_mkpeer(node_p node, const char *name, const char *name2, char *type)
1448{
1449 node_p node2;
1450 hook_p hook1, hook2;
1451 int error;
1452
1453 if ((error = ng_make_node(type, &node2))) {
1454 return (error);
1455 }
1456
1457 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */
1458 ng_rmnode(node2, NULL, NULL, 0);
1459 return (error);
1460 }
1461
1462 if ((error = ng_add_hook(node2, name2, &hook2))) {
1463 ng_rmnode(node2, NULL, NULL, 0);
1464 ng_destroy_hook(hook1);
1465 NG_HOOK_UNREF(hook1);
1466 return (error);
1467 }
1468
1469 /*
1470 * Actually link the two hooks together.
1471 */
1472 hook1->hk_peer = hook2;
1473 hook2->hk_peer = hook1;
1474
1475 /* Each hook is referenced by the other */
1476 NG_HOOK_REF(hook1);
1477 NG_HOOK_REF(hook2);
1478
1479 /* Give each node the opportunity to veto the pending connection */
1480 if (hook1->hk_node->nd_type->connect) {
1481 error = (*hook1->hk_node->nd_type->connect) (hook1);
1482 }
1483
1484 if ((error == 0) && hook2->hk_node->nd_type->connect) {
1485 error = (*hook2->hk_node->nd_type->connect) (hook2);
1486
1487 }
1488
1489 /*
1490 * drop the references we were holding on the two hooks.
1491 */
1492 if (error) {
1493 ng_destroy_hook(hook2); /* also zaps hook1 */
1494 ng_rmnode(node2, NULL, NULL, 0);
1495 } else {
1496 /* As a last act, allow the hooks to be used */
1497 hook1->hk_flags &= ~HK_INVALID;
1498 hook2->hk_flags &= ~HK_INVALID;
1499 }
1500 NG_HOOK_UNREF(hook1);
1501 NG_HOOK_UNREF(hook2);
1502 return (error);
1503}
1504
1505/************************************************************************
1506 Utility routines to send self messages
1507************************************************************************/
1508
1509/* Shut this node down as soon as everyone is clear of it */
1510/* Should add arg "immediately" to jump the queue */
1511int
1512ng_rmnode_self(node_p node)
1513{
1514 int error;
1515
1516 if (node == &ng_deadnode)
1517 return (0);
1518 node->nd_flags |= NGF_INVALID;
1519 if (node->nd_flags & NGF_CLOSING)
1520 return (0);
1521
1522 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0);
1523 return (error);
1524}
1525
1526static void
1527ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2)
1528{
1529 ng_destroy_hook(hook);
1530 return ;
1531}
1532
1533int
1534ng_rmhook_self(hook_p hook)
1535{
1536 int error;
1537 node_p node = NG_HOOK_NODE(hook);
1538
1539 if (node == &ng_deadnode)
1540 return (0);
1541
1542 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0);
1543 return (error);
1544}
1545
1546/***********************************************************************
1547 * Parse and verify a string of the form: <NODE:><PATH>
1548 *
1549 * Such a string can refer to a specific node or a specific hook
1550 * on a specific node, depending on how you look at it. In the
1551 * latter case, the PATH component must not end in a dot.
1552 *
1553 * Both <NODE:> and <PATH> are optional. The <PATH> is a string
1554 * of hook names separated by dots. This breaks out the original
1555 * string, setting *nodep to "NODE" (or NULL if none) and *pathp
1556 * to "PATH" (or NULL if degenerate). Also, *hookp will point to
1557 * the final hook component of <PATH>, if any, otherwise NULL.
1558 *
1559 * This returns -1 if the path is malformed. The char ** are optional.
1560 ***********************************************************************/
1561int
1562ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp)
1563{
1564 char *node, *path, *hook;
1565 int k;
1566
1567 /*
1568 * Extract absolute NODE, if any
1569 */
1570 for (path = addr; *path && *path != ':'; path++);
1571 if (*path) {
1572 node = addr; /* Here's the NODE */
1573 *path++ = '\0'; /* Here's the PATH */
1574
1575 /* Node name must not be empty */
1576 if (!*node)
1577 return -1;
1578
1579 /* A name of "." is OK; otherwise '.' not allowed */
1580 if (strcmp(node, ".") != 0) {
1581 for (k = 0; node[k]; k++)
1582 if (node[k] == '.')
1583 return -1;
1584 }
1585 } else {
1586 node = NULL; /* No absolute NODE */
1587 path = addr; /* Here's the PATH */
1588 }
1589
1590 /* Snoop for illegal characters in PATH */
1591 for (k = 0; path[k]; k++)
1592 if (path[k] == ':')
1593 return -1;
1594
1595 /* Check for no repeated dots in PATH */
1596 for (k = 0; path[k]; k++)
1597 if (path[k] == '.' && path[k + 1] == '.')
1598 return -1;
1599
1600 /* Remove extra (degenerate) dots from beginning or end of PATH */
1601 if (path[0] == '.')
1602 path++;
1603 if (*path && path[strlen(path) - 1] == '.')
1604 path[strlen(path) - 1] = 0;
1605
1606 /* If PATH has a dot, then we're not talking about a hook */
1607 if (*path) {
1608 for (hook = path, k = 0; path[k]; k++)
1609 if (path[k] == '.') {
1610 hook = NULL;
1611 break;
1612 }
1613 } else
1614 path = hook = NULL;
1615
1616 /* Done */
1617 if (nodep)
1618 *nodep = node;
1619 if (pathp)
1620 *pathp = path;
1621 if (hookp)
1622 *hookp = hook;
1623 return (0);
1624}
1625
1626/*
1627 * Given a path, which may be absolute or relative, and a starting node,
1628 * return the destination node.
1629 */
1630int
1631ng_path2noderef(node_p here, const char *address,
1632 node_p *destp, hook_p *lasthook)
1633{
1634 char fullpath[NG_PATHSIZ];
1635 char *nodename, *path, pbuf[2];
1636 node_p node, oldnode;
1637 char *cp;
1638 hook_p hook = NULL;
1639
1640 /* Initialize */
1641 if (destp == NULL) {
1642 TRAP_ERROR();
1643 return EINVAL;
1644 }
1645 *destp = NULL;
1646
1647 /* Make a writable copy of address for ng_path_parse() */
1648 strncpy(fullpath, address, sizeof(fullpath) - 1);
1649 fullpath[sizeof(fullpath) - 1] = '\0';
1650
1651 /* Parse out node and sequence of hooks */
1652 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) {
1653 TRAP_ERROR();
1654 return EINVAL;
1655 }
1656 if (path == NULL) {
1657 pbuf[0] = '.'; /* Needs to be writable */
1658 pbuf[1] = '\0';
1659 path = pbuf;
1660 }
1661
1662 /*
1663 * For an absolute address, jump to the starting node.
1664 * Note that this holds a reference on the node for us.
1665 * Don't forget to drop the reference if we don't need it.
1666 */
1667 if (nodename) {
1668 node = ng_name2noderef(here, nodename);
1669 if (node == NULL) {
1670 TRAP_ERROR();
1671 return (ENOENT);
1672 }
1673 } else {
1674 if (here == NULL) {
1675 TRAP_ERROR();
1676 return (EINVAL);
1677 }
1678 node = here;
1679 NG_NODE_REF(node);
1680 }
1681
1682 /*
1683 * Now follow the sequence of hooks
1684 * XXX
1685 * We actually cannot guarantee that the sequence
1686 * is not being demolished as we crawl along it
1687 * without extra-ordinary locking etc.
1688 * So this is a bit dodgy to say the least.
1689 * We can probably hold up some things by holding
1690 * the nodelist mutex for the time of this
1691 * crawl if we wanted.. At least that way we wouldn't have to
1692 * worry about the nodes disappearing, but the hooks would still
1693 * be a problem.
1694 */
1695 for (cp = path; node != NULL && *cp != '\0'; ) {
1696 char *segment;
1697
1698 /*
1699 * Break out the next path segment. Replace the dot we just
1700 * found with a NUL; "cp" points to the next segment (or the
1701 * NUL at the end).
1702 */
1703 for (segment = cp; *cp != '\0'; cp++) {
1704 if (*cp == '.') {
1705 *cp++ = '\0';
1706 break;
1707 }
1708 }
1709
1710 /* Empty segment */
1711 if (*segment == '\0')
1712 continue;
1713
1714 /* We have a segment, so look for a hook by that name */
1715 hook = ng_findhook(node, segment);
1716
1717 /* Can't get there from here... */
1718 if (hook == NULL
1719 || NG_HOOK_PEER(hook) == NULL
1720 || NG_HOOK_NOT_VALID(hook)
1721 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) {
1722 TRAP_ERROR();
1723 NG_NODE_UNREF(node);
1724#if 0
1725 printf("hooknotvalid %s %s %d %d %d %d ",
1726 path,
1727 segment,
1728 hook == NULL,
1729 NG_HOOK_PEER(hook) == NULL,
1730 NG_HOOK_NOT_VALID(hook),
1731 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)));
1732#endif
1733 return (ENOENT);
1734 }
1735
1736 /*
1737 * Hop on over to the next node
1738 * XXX
1739 * Big race conditions here as hooks and nodes go away
1740 * *** Idea.. store an ng_ID_t in each hook and use that
1741 * instead of the direct hook in this crawl?
1742 */
1743 oldnode = node;
1744 if ((node = NG_PEER_NODE(hook)))
1745 NG_NODE_REF(node); /* XXX RACE */
1746 NG_NODE_UNREF(oldnode); /* XXX another race */
1747 if (NG_NODE_NOT_VALID(node)) {
1748 NG_NODE_UNREF(node); /* XXX more races */
1749 node = NULL;
1750 }
1751 }
1752
1753 /* If node somehow missing, fail here (probably this is not needed) */
1754 if (node == NULL) {
1755 TRAP_ERROR();
1756 return (ENXIO);
1757 }
1758
1759 /* Done */
1760 *destp = node;
1761 if (lasthook != NULL)
1762 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL);
1763 return (0);
1764}
1765
1766/***************************************************************\
1767* Input queue handling.
1768* All activities are submitted to the node via the input queue
1769* which implements a multiple-reader/single-writer gate.
1770* Items which cannot be handled immediately are queued.
1771*
1772* read-write queue locking inline functions *
1773\***************************************************************/
1774
1775static __inline void ng_queue_rw(node_p node, item_p item, int rw);
1776static __inline item_p ng_dequeue(node_p node, int *rw);
1777static __inline item_p ng_acquire_read(node_p node, item_p item);
1778static __inline item_p ng_acquire_write(node_p node, item_p item);
1779static __inline void ng_leave_read(node_p node);
1780static __inline void ng_leave_write(node_p node);
1781
1782/*
1783 * Definition of the bits fields in the ng_queue flag word.
1784 * Defined here rather than in netgraph.h because no-one should fiddle
1785 * with them.
1786 *
1787 * The ordering here may be important! don't shuffle these.
1788 */
1789/*-
1790 Safety Barrier--------+ (adjustable to suit taste) (not used yet)
1791 |
1792 V
1793+-------+-------+-------+-------+-------+-------+-------+-------+
1794 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
1795 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |P|A|
1796 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |O|W|
1797+-------+-------+-------+-------+-------+-------+-------+-------+
1798 \___________________________ ____________________________/ | |
1799 V | |
1800 [active reader count] | |
1801 | |
1802 Operation Pending -------------------------------+ |
1803 |
1804 Active Writer ---------------------------------------+
1805
1806Node queue has such semantics:
1807- All flags modifications are atomic.
1808- Reader count can be incremented only if there is no writer or pending flags.
1809 As soon as this can't be done with single operation, it is implemented with
1810 spin loop and atomic_cmpset().
1811- Writer flag can be set only if there is no any bits set.
1812 It is implemented with atomic_cmpset().
1813- Pending flag can be set any time, but to avoid collision on queue processing
1814 all queue fields are protected by the mutex.
1815- Queue processing thread reads queue holding the mutex, but releases it while
1816 processing. When queue is empty pending flag is removed.
1817*/
1818
1819#define WRITER_ACTIVE 0x00000001
1820#define OP_PENDING 0x00000002
1821#define READER_INCREMENT 0x00000004
1822#define READER_MASK 0xfffffffc /* Not valid if WRITER_ACTIVE is set */
1823#define SAFETY_BARRIER 0x00100000 /* 128K items queued should be enough */
1824
1825/* Defines of more elaborate states on the queue */
1826/* Mask of bits a new read cares about */
1827#define NGQ_RMASK (WRITER_ACTIVE|OP_PENDING)
1828
1829/* Mask of bits a new write cares about */
1830#define NGQ_WMASK (NGQ_RMASK|READER_MASK)
1831
1832/* Test to decide if there is something on the queue. */
1833#define QUEUE_ACTIVE(QP) ((QP)->q_flags & OP_PENDING)
1834
1835/* How to decide what the next queued item is. */
1836#define HEAD_IS_READER(QP) NGI_QUEUED_READER(STAILQ_FIRST(&(QP)->queue))
1837#define HEAD_IS_WRITER(QP) NGI_QUEUED_WRITER(STAILQ_FIRST(&(QP)->queue)) /* notused */
1838
1839/* Read the status to decide if the next item on the queue can now run. */
1840#define QUEUED_READER_CAN_PROCEED(QP) \
1841 (((QP)->q_flags & (NGQ_RMASK & ~OP_PENDING)) == 0)
1842#define QUEUED_WRITER_CAN_PROCEED(QP) \
1843 (((QP)->q_flags & (NGQ_WMASK & ~OP_PENDING)) == 0)
1844
1845/* Is there a chance of getting ANY work off the queue? */
1846#define NEXT_QUEUED_ITEM_CAN_PROCEED(QP) \
1847 ((HEAD_IS_READER(QP)) ? QUEUED_READER_CAN_PROCEED(QP) : \
1848 QUEUED_WRITER_CAN_PROCEED(QP))
1849
1850#define NGQRW_R 0
1851#define NGQRW_W 1
1852
1853#define NGQ2_WORKQ 0x00000001
1854
1855/*
1856 * Taking into account the current state of the queue and node, possibly take
1857 * the next entry off the queue and return it. Return NULL if there was
1858 * nothing we could return, either because there really was nothing there, or
1859 * because the node was in a state where it cannot yet process the next item
1860 * on the queue.
1861 */
1862static __inline item_p
1863ng_dequeue(node_p node, int *rw)
1864{
1865 item_p item;
1866 struct ng_queue *ngq = &node->nd_input_queue;
1867
1868 /* This MUST be called with the mutex held. */
1869 mtx_assert(&ngq->q_mtx, MA_OWNED);
1870
1871 /* If there is nothing queued, then just return. */
1872 if (!QUEUE_ACTIVE(ngq)) {
1873 CTR4(KTR_NET, "%20s: node [%x] (%p) queue empty; "
1874 "queue flags 0x%lx", __func__,
1875 node->nd_ID, node, ngq->q_flags);
1876 return (NULL);
1877 }
1878
1879 /*
1880 * From here, we can assume there is a head item.
1881 * We need to find out what it is and if it can be dequeued, given
1882 * the current state of the node.
1883 */
1884 if (HEAD_IS_READER(ngq)) {
1885 while (1) {
1886 long t = ngq->q_flags;
1887 if (t & WRITER_ACTIVE) {
1888 /* There is writer, reader can't proceed. */
1889 CTR4(KTR_NET, "%20s: node [%x] (%p) queued reader "
1890 "can't proceed; queue flags 0x%lx", __func__,
1891 node->nd_ID, node, t);
1892 return (NULL);
1893 }
1894 if (atomic_cmpset_acq_int(&ngq->q_flags, t,
1895 t + READER_INCREMENT))
1896 break;
1897 cpu_spinwait();
1898 }
1899 /* We have got reader lock for the node. */
1900 *rw = NGQRW_R;
1901 } else if (atomic_cmpset_acq_int(&ngq->q_flags, OP_PENDING,
1902 OP_PENDING + WRITER_ACTIVE)) {
1903 /* We have got writer lock for the node. */
1904 *rw = NGQRW_W;
1905 } else {
1906 /* There is somebody other, writer can't proceed. */
1907 CTR4(KTR_NET, "%20s: node [%x] (%p) queued writer "
1908 "can't proceed; queue flags 0x%lx", __func__,
1909 node->nd_ID, node, ngq->q_flags);
1910 return (NULL);
1911 }
1912
1913 /*
1914 * Now we dequeue the request (whatever it may be) and correct the
1915 * pending flags and the next and last pointers.
1916 */
1917 item = STAILQ_FIRST(&ngq->queue);
1918 STAILQ_REMOVE_HEAD(&ngq->queue, el_next);
1919 if (STAILQ_EMPTY(&ngq->queue))
1920 atomic_clear_int(&ngq->q_flags, OP_PENDING);
1921 CTR6(KTR_NET, "%20s: node [%x] (%p) returning item %p as %s; "
1922 "queue flags 0x%lx", __func__,
1923 node->nd_ID, node, item, *rw ? "WRITER" : "READER" ,
1924 ngq->q_flags);
1925 return (item);
1926}
1927
1928/*
1929 * Queue a packet to be picked up later by someone else.
1930 * If the queue could be run now, add node to the queue handler's worklist.
1931 */
1932static __inline void
1933ng_queue_rw(node_p node, item_p item, int rw)
1934{
1935 struct ng_queue *ngq = &node->nd_input_queue;
1936 if (rw == NGQRW_W)
1937 NGI_SET_WRITER(item);
1938 else
1939 NGI_SET_READER(item);
1940
1941 NG_QUEUE_LOCK(ngq);
1942 /* Set OP_PENDING flag and enqueue the item. */
1943 atomic_set_int(&ngq->q_flags, OP_PENDING);
1944 STAILQ_INSERT_TAIL(&ngq->queue, item, el_next);
1945
1946 CTR5(KTR_NET, "%20s: node [%x] (%p) queued item %p as %s", __func__,
1947 node->nd_ID, node, item, rw ? "WRITER" : "READER" );
1948
1949 /*
1950 * We can take the worklist lock with the node locked
1951 * BUT NOT THE REVERSE!
1952 */
1953 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
1954 ng_worklist_add(node);
1955 NG_QUEUE_UNLOCK(ngq);
1956}
1957
1958/* Acquire reader lock on node. If node is busy, queue the packet. */
1959static __inline item_p
1960ng_acquire_read(node_p node, item_p item)
1961{
1962 KASSERT(node != &ng_deadnode,
1963 ("%s: working on deadnode", __func__));
1964
1965 /* Reader needs node without writer and pending items. */
1966 while (1) {
1967 long t = node->nd_input_queue.q_flags;
1968 if (t & NGQ_RMASK)
1969 break; /* Node is not ready for reader. */
1970 if (atomic_cmpset_acq_int(&node->nd_input_queue.q_flags,
1971 t, t + READER_INCREMENT)) {
1972 /* Successfully grabbed node */
1973 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p",
1974 __func__, node->nd_ID, node, item);
1975 return (item);
1976 }
1977 cpu_spinwait();
1978 };
1979
1980 /* Queue the request for later. */
1981 ng_queue_rw(node, item, NGQRW_R);
1982
1983 return (NULL);
1984}
1985
1986/* Acquire writer lock on node. If node is busy, queue the packet. */
1987static __inline item_p
1988ng_acquire_write(node_p node, item_p item)
1989{
1990 KASSERT(node != &ng_deadnode,
1991 ("%s: working on deadnode", __func__));
1992
1993 /* Writer needs completely idle node. */
1994 if (atomic_cmpset_acq_int(&node->nd_input_queue.q_flags,
1995 0, WRITER_ACTIVE)) {
1996 /* Successfully grabbed node */
1997 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p",
1998 __func__, node->nd_ID, node, item);
1999 return (item);
2000 }
2001
2002 /* Queue the request for later. */
2003 ng_queue_rw(node, item, NGQRW_W);
2004
2005 return (NULL);
2006}
2007
2008#if 0
2009static __inline item_p
2010ng_upgrade_write(node_p node, item_p item)
2011{
2012 struct ng_queue *ngq = &node->nd_input_queue;
2013 KASSERT(node != &ng_deadnode,
2014 ("%s: working on deadnode", __func__));
2015
2016 NGI_SET_WRITER(item);
2017
2018 NG_QUEUE_LOCK(ngq);
2019
2020 /*
2021 * There will never be no readers as we are there ourselves.
2022 * Set the WRITER_ACTIVE flags ASAP to block out fast track readers.
2023 * The caller we are running from will call ng_leave_read()
2024 * soon, so we must account for that. We must leave again with the
2025 * READER lock. If we find other readers, then
2026 * queue the request for later. However "later" may be rignt now
2027 * if there are no readers. We don't really care if there are queued
2028 * items as we will bypass them anyhow.
2029 */
2030 atomic_add_int(&ngq->q_flags, WRITER_ACTIVE - READER_INCREMENT);
2031 if ((ngq->q_flags & (NGQ_WMASK & ~OP_PENDING)) == WRITER_ACTIVE) {
2032 NG_QUEUE_UNLOCK(ngq);
2033
2034 /* It's just us, act on the item. */
2035 /* will NOT drop writer lock when done */
2036 ng_apply_item(node, item, 0);
2037
2038 /*
2039 * Having acted on the item, atomically
2040 * down grade back to READER and finish up
2041 */
2042 atomic_add_int(&ngq->q_flags,
2043 READER_INCREMENT - WRITER_ACTIVE);
2044
2045 /* Our caller will call ng_leave_read() */
2046 return;
2047 }
2048 /*
2049 * It's not just us active, so queue us AT THE HEAD.
2050 * "Why?" I hear you ask.
2051 * Put us at the head of the queue as we've already been
2052 * through it once. If there is nothing else waiting,
2053 * set the correct flags.
2054 */
2055 if (STAILQ_EMPTY(&ngq->queue)) {
2056 /* We've gone from, 0 to 1 item in the queue */
2057 atomic_set_int(&ngq->q_flags, OP_PENDING);
2058
2059 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__,
2060 node->nd_ID, node);
2061 };
2062 STAILQ_INSERT_HEAD(&ngq->queue, item, el_next);
2063 CTR4(KTR_NET, "%20s: node [%x] (%p) requeued item %p as WRITER",
2064 __func__, node->nd_ID, node, item );
2065
2066 /* Reverse what we did above. That downgrades us back to reader */
2067 atomic_add_int(&ngq->q_flags, READER_INCREMENT - WRITER_ACTIVE);
2068 if (QUEUE_ACTIVE(ngq) && NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2069 ng_worklist_add(node);
2070 NG_QUEUE_UNLOCK(ngq);
2071
2072 return;
2073}
2074#endif
2075
2076/* Release reader lock. */
2077static __inline void
2078ng_leave_read(node_p node)
2079{
2080 atomic_subtract_rel_int(&node->nd_input_queue.q_flags, READER_INCREMENT);
2081}
2082
2083/* Release writer lock. */
2084static __inline void
2085ng_leave_write(node_p node)
2086{
2087 atomic_clear_rel_int(&node->nd_input_queue.q_flags, WRITER_ACTIVE);
2088}
2089
2090/* Purge node queue. Called on node shutdown. */
2091static void
2092ng_flush_input_queue(node_p node)
2093{
2094 struct ng_queue *ngq = &node->nd_input_queue;
2095 item_p item;
2096
2097 NG_QUEUE_LOCK(ngq);
2098 while ((item = STAILQ_FIRST(&ngq->queue)) != NULL) {
2099 STAILQ_REMOVE_HEAD(&ngq->queue, el_next);
2100 if (STAILQ_EMPTY(&ngq->queue))
2101 atomic_clear_int(&ngq->q_flags, OP_PENDING);
2102 NG_QUEUE_UNLOCK(ngq);
2103
2104 /* If the item is supplying a callback, call it with an error */
2105 if (item->apply != NULL) {
2106 if (item->depth == 1)
2107 item->apply->error = ENOENT;
2108 if (refcount_release(&item->apply->refs)) {
2109 (*item->apply->apply)(item->apply->context,
2110 item->apply->error);
2111 }
2112 }
2113 NG_FREE_ITEM(item);
2114 NG_QUEUE_LOCK(ngq);
2115 }
2116 NG_QUEUE_UNLOCK(ngq);
2117}
2118
2119/***********************************************************************
2120* Externally visible method for sending or queueing messages or data.
2121***********************************************************************/
2122
2123/*
2124 * The module code should have filled out the item correctly by this stage:
2125 * Common:
2126 * reference to destination node.
2127 * Reference to destination rcv hook if relevant.
2128 * apply pointer must be or NULL or reference valid struct ng_apply_info.
2129 * Data:
2130 * pointer to mbuf
2131 * Control_Message:
2132 * pointer to msg.
2133 * ID of original sender node. (return address)
2134 * Function:
2135 * Function pointer
2136 * void * argument
2137 * integer argument
2138 *
2139 * The nodes have several routines and macros to help with this task:
2140 */
2141
2142int
2143ng_snd_item(item_p item, int flags)
2144{
2145 hook_p hook;
2146 node_p node;
2147 int queue, rw;
2148 struct ng_queue *ngq;
2149 int error = 0;
2150
2151 /* We are sending item, so it must be present! */
2152 KASSERT(item != NULL, ("ng_snd_item: item is NULL"));
2153
2154#ifdef NETGRAPH_DEBUG
2155 _ngi_check(item, __FILE__, __LINE__);
2156#endif
2157
2158 /* Item was sent once more, postpone apply() call. */
2159 if (item->apply)
2160 refcount_acquire(&item->apply->refs);
2161
2162 node = NGI_NODE(item);
2163 /* Node is never optional. */
2164 KASSERT(node != NULL, ("ng_snd_item: node is NULL"));
2165
2166 hook = NGI_HOOK(item);
2167 /* Valid hook and mbuf are mandatory for data. */
2168 if ((item->el_flags & NGQF_TYPE) == NGQF_DATA) {
2169 KASSERT(hook != NULL, ("ng_snd_item: hook for data is NULL"));
2170 if (NGI_M(item) == NULL)
2171 ERROUT(EINVAL);
2172 CHECK_DATA_MBUF(NGI_M(item));
2173 }
2174
2175 /*
2176 * If the item or the node specifies single threading, force
2177 * writer semantics. Similarly, the node may say one hook always
2178 * produces writers. These are overrides.
2179 */
2180 if (((item->el_flags & NGQF_RW) == NGQF_WRITER) ||
2181 (node->nd_flags & NGF_FORCE_WRITER) ||
2182 (hook && (hook->hk_flags & HK_FORCE_WRITER))) {
2183 rw = NGQRW_W;
2184 } else {
2185 rw = NGQRW_R;
2186 }
2187
2188 /*
2189 * If sender or receiver requests queued delivery or stack usage
2190 * level is dangerous - enqueue message.
2191 */
2192 if ((flags & NG_QUEUE) || (hook && (hook->hk_flags & HK_QUEUE))) {
2193 queue = 1;
2194 } else {
2195 queue = 0;
2196#ifdef GET_STACK_USAGE
2197 /*
2198 * Most of netgraph nodes have small stack consumption and
2199 * for them 25% of free stack space is more than enough.
2200 * Nodes/hooks with higher stack usage should be marked as
2201 * HI_STACK. For them 50% of stack will be guaranteed then.
2202 * XXX: Values 25% and 50% are completely empirical.
2203 */
2204 size_t st, su, sl;
2205 GET_STACK_USAGE(st, su);
2206 sl = st - su;
2207 if ((sl * 4 < st) ||
2208 ((sl * 2 < st) && ((node->nd_flags & NGF_HI_STACK) ||
2209 (hook && (hook->hk_flags & HK_HI_STACK))))) {
2210 queue = 1;
2211 }
2212#endif
2213 }
2214
2215 if (queue) {
2216 item->depth = 1;
2217 /* Put it on the queue for that node*/
2218 ng_queue_rw(node, item, rw);
2219 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0);
2220 }
2221
2222 /*
2223 * We already decided how we will be queueud or treated.
2224 * Try get the appropriate operating permission.
2225 */
2226 if (rw == NGQRW_R)
2227 item = ng_acquire_read(node, item);
2228 else
2229 item = ng_acquire_write(node, item);
2230
2231 /* Item was queued while trying to get permission. */
2232 if (item == NULL)
2233 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0);
2234
2235 NGI_GET_NODE(item, node); /* zaps stored node */
2236
2237 item->depth++;
2238 error = ng_apply_item(node, item, rw); /* drops r/w lock when done */
2239
2240 /* If something is waiting on queue and ready, schedule it. */
2241 ngq = &node->nd_input_queue;
2242 if (QUEUE_ACTIVE(ngq)) {
2243 NG_QUEUE_LOCK(ngq);
2244 if (QUEUE_ACTIVE(ngq) && NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2245 ng_worklist_add(node);
2246 NG_QUEUE_UNLOCK(ngq);
2247 }
2248
2249 /*
2250 * Node may go away as soon as we remove the reference.
2251 * Whatever we do, DO NOT access the node again!
2252 */
2253 NG_NODE_UNREF(node);
2254
2255 return (error);
2256
2257done:
2258 /* If was not sent, apply callback here. */
2259 if (item->apply != NULL) {
2260 if (item->depth == 0 && error != 0)
2261 item->apply->error = error;
2262 if (refcount_release(&item->apply->refs)) {
2263 (*item->apply->apply)(item->apply->context,
2264 item->apply->error);
2265 }
2266 }
2267
2268 NG_FREE_ITEM(item);
2269 return (error);
2270}
2271
2272/*
2273 * We have an item that was possibly queued somewhere.
2274 * It should contain all the information needed
2275 * to run it on the appropriate node/hook.
2276 * If there is apply pointer and we own the last reference, call apply().
2277 */
2278static int
2279ng_apply_item(node_p node, item_p item, int rw)
2280{
2281 hook_p hook;
2282 ng_rcvdata_t *rcvdata;
2283 ng_rcvmsg_t *rcvmsg;
2284 struct ng_apply_info *apply;
2285 int error = 0, depth;
2286
2287 /* Node and item are never optional. */
2288 KASSERT(node != NULL, ("ng_apply_item: node is NULL"));
2289 KASSERT(item != NULL, ("ng_apply_item: item is NULL"));
2290
2291 NGI_GET_HOOK(item, hook); /* clears stored hook */
2292#ifdef NETGRAPH_DEBUG
2293 _ngi_check(item, __FILE__, __LINE__);
2294#endif
2295
2296 apply = item->apply;
2297 depth = item->depth;
2298
2299 switch (item->el_flags & NGQF_TYPE) {
2300 case NGQF_DATA:
2301 /*
2302 * Check things are still ok as when we were queued.
2303 */
2304 KASSERT(hook != NULL, ("ng_apply_item: hook for data is NULL"));
2305 if (NG_HOOK_NOT_VALID(hook) ||
2306 NG_NODE_NOT_VALID(node)) {
2307 error = EIO;
2308 NG_FREE_ITEM(item);
2309 break;
2310 }
2311 /*
2312 * If no receive method, just silently drop it.
2313 * Give preference to the hook over-ride method
2314 */
2315 if ((!(rcvdata = hook->hk_rcvdata))
2316 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) {
2317 error = 0;
2318 NG_FREE_ITEM(item);
2319 break;
2320 }
2321 error = (*rcvdata)(hook, item);
2322 break;
2323 case NGQF_MESG:
2324 if (hook && NG_HOOK_NOT_VALID(hook)) {
2325 /*
2326 * The hook has been zapped then we can't use it.
2327 * Immediately drop its reference.
2328 * The message may not need it.
2329 */
2330 NG_HOOK_UNREF(hook);
2331 hook = NULL;
2332 }
2333 /*
2334 * Similarly, if the node is a zombie there is
2335 * nothing we can do with it, drop everything.
2336 */
2337 if (NG_NODE_NOT_VALID(node)) {
2338 TRAP_ERROR();
2339 error = EINVAL;
2340 NG_FREE_ITEM(item);
2341 break;
2342 }
2343 /*
2344 * Call the appropriate message handler for the object.
2345 * It is up to the message handler to free the message.
2346 * If it's a generic message, handle it generically,
2347 * otherwise call the type's message handler (if it exists).
2348 * XXX (race). Remember that a queued message may
2349 * reference a node or hook that has just been
2350 * invalidated. It will exist as the queue code
2351 * is holding a reference, but..
2352 */
2353 if ((NGI_MSG(item)->header.typecookie == NGM_GENERIC_COOKIE) &&
2354 ((NGI_MSG(item)->header.flags & NGF_RESP) == 0)) {
2355 error = ng_generic_msg(node, item, hook);
2356 break;
2357 }
2358 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) &&
2359 (!(rcvmsg = node->nd_type->rcvmsg))) {
2360 TRAP_ERROR();
2361 error = 0;
2362 NG_FREE_ITEM(item);
2363 break;
2364 }
2365 error = (*rcvmsg)(node, item, hook);
2366 break;
2367 case NGQF_FN:
2368 case NGQF_FN2:
2369 /*
2370 * We have to implicitly trust the hook,
2371 * as some of these are used for system purposes
2372 * where the hook is invalid. In the case of
2373 * the shutdown message we allow it to hit
2374 * even if the node is invalid.
2375 */
2376 if ((NG_NODE_NOT_VALID(node))
2377 && (NGI_FN(item) != &ng_rmnode)) {
2378 TRAP_ERROR();
2379 error = EINVAL;
2380 NG_FREE_ITEM(item);
2381 break;
2382 }
2383 if ((item->el_flags & NGQF_TYPE) == NGQF_FN) {
2384 (*NGI_FN(item))(node, hook, NGI_ARG1(item),
2385 NGI_ARG2(item));
2386 NG_FREE_ITEM(item);
2387 } else /* it is NGQF_FN2 */
2388 error = (*NGI_FN2(item))(node, item, hook);
2389 break;
2390 }
2391 /*
2392 * We held references on some of the resources
2393 * that we took from the item. Now that we have
2394 * finished doing everything, drop those references.
2395 */
2396 if (hook)
2397 NG_HOOK_UNREF(hook);
2398
2399 if (rw == NGQRW_R)
2400 ng_leave_read(node);
2401 else
2402 ng_leave_write(node);
2403
2404 /* Apply callback. */
2405 if (apply != NULL) {
2406 if (depth == 1 && error != 0)
2407 apply->error = error;
2408 if (refcount_release(&apply->refs))
2409 (*apply->apply)(apply->context, apply->error);
2410 }
2411
2412 return (error);
2413}
2414
2415/***********************************************************************
2416 * Implement the 'generic' control messages
2417 ***********************************************************************/
2418static int
2419ng_generic_msg(node_p here, item_p item, hook_p lasthook)
2420{
2421 int error = 0;
2422 struct ng_mesg *msg;
2423 struct ng_mesg *resp = NULL;
2424
2425 NGI_GET_MSG(item, msg);
2426 if (msg->header.typecookie != NGM_GENERIC_COOKIE) {
2427 TRAP_ERROR();
2428 error = EINVAL;
2429 goto out;
2430 }
2431 switch (msg->header.cmd) {
2432 case NGM_SHUTDOWN:
2433 ng_rmnode(here, NULL, NULL, 0);
2434 break;
2435 case NGM_MKPEER:
2436 {
2437 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data;
2438
2439 if (msg->header.arglen != sizeof(*mkp)) {
2440 TRAP_ERROR();
2441 error = EINVAL;
2442 break;
2443 }
2444 mkp->type[sizeof(mkp->type) - 1] = '\0';
2445 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0';
2446 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0';
2447 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type);
2448 break;
2449 }
2450 case NGM_CONNECT:
2451 {
2452 struct ngm_connect *const con =
2453 (struct ngm_connect *) msg->data;
2454 node_p node2;
2455
2456 if (msg->header.arglen != sizeof(*con)) {
2457 TRAP_ERROR();
2458 error = EINVAL;
2459 break;
2460 }
2461 con->path[sizeof(con->path) - 1] = '\0';
2462 con->ourhook[sizeof(con->ourhook) - 1] = '\0';
2463 con->peerhook[sizeof(con->peerhook) - 1] = '\0';
2464 /* Don't forget we get a reference.. */
2465 error = ng_path2noderef(here, con->path, &node2, NULL);
2466 if (error)
2467 break;
2468 error = ng_con_nodes(item, here, con->ourhook,
2469 node2, con->peerhook);
2470 NG_NODE_UNREF(node2);
2471 break;
2472 }
2473 case NGM_NAME:
2474 {
2475 struct ngm_name *const nam = (struct ngm_name *) msg->data;
2476
2477 if (msg->header.arglen != sizeof(*nam)) {
2478 TRAP_ERROR();
2479 error = EINVAL;
2480 break;
2481 }
2482 nam->name[sizeof(nam->name) - 1] = '\0';
2483 error = ng_name_node(here, nam->name);
2484 break;
2485 }
2486 case NGM_RMHOOK:
2487 {
2488 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data;
2489 hook_p hook;
2490
2491 if (msg->header.arglen != sizeof(*rmh)) {
2492 TRAP_ERROR();
2493 error = EINVAL;
2494 break;
2495 }
2496 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0';
2497 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL)
2498 ng_destroy_hook(hook);
2499 break;
2500 }
2501 case NGM_NODEINFO:
2502 {
2503 struct nodeinfo *ni;
2504
5a975a3d 2505 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_WAITOK | M_NULLOK);
b06ebda0
MD
2506 if (resp == NULL) {
2507 error = ENOMEM;
2508 break;
2509 }
2510
2511 /* Fill in node info */
2512 ni = (struct nodeinfo *) resp->data;
2513 if (NG_NODE_HAS_NAME(here))
2514 strcpy(ni->name, NG_NODE_NAME(here));
2515 strcpy(ni->type, here->nd_type->name);
2516 ni->id = ng_node2ID(here);
2517 ni->hooks = here->nd_numhooks;
2518 break;
2519 }
2520 case NGM_LISTHOOKS:
2521 {
2522 const int nhooks = here->nd_numhooks;
2523 struct hooklist *hl;
2524 struct nodeinfo *ni;
2525 hook_p hook;
2526
2527 /* Get response struct */
2528 NG_MKRESPONSE(resp, msg, sizeof(*hl)
5a975a3d 2529 + (nhooks * sizeof(struct linkinfo)), M_WAITOK | M_NULLOK);
b06ebda0
MD
2530 if (resp == NULL) {
2531 error = ENOMEM;
2532 break;
2533 }
2534 hl = (struct hooklist *) resp->data;
2535 ni = &hl->nodeinfo;
2536
2537 /* Fill in node info */
2538 if (NG_NODE_HAS_NAME(here))
2539 strcpy(ni->name, NG_NODE_NAME(here));
2540 strcpy(ni->type, here->nd_type->name);
2541 ni->id = ng_node2ID(here);
2542
2543 /* Cycle through the linked list of hooks */
2544 ni->hooks = 0;
2545 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) {
2546 struct linkinfo *const link = &hl->link[ni->hooks];
2547
2548 if (ni->hooks >= nhooks) {
2549 log(LOG_ERR, "%s: number of %s changed\n",
2550 __func__, "hooks");
2551 break;
2552 }
2553 if (NG_HOOK_NOT_VALID(hook))
2554 continue;
2555 strcpy(link->ourhook, NG_HOOK_NAME(hook));
2556 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook));
2557 if (NG_PEER_NODE_NAME(hook)[0] != '\0')
2558 strcpy(link->nodeinfo.name,
2559 NG_PEER_NODE_NAME(hook));
2560 strcpy(link->nodeinfo.type,
2561 NG_PEER_NODE(hook)->nd_type->name);
2562 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook));
2563 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks;
2564 ni->hooks++;
2565 }
2566 break;
2567 }
2568
2569 case NGM_LISTNAMES:
2570 case NGM_LISTNODES:
2571 {
2572 const int unnamed = (msg->header.cmd == NGM_LISTNODES);
2573 struct namelist *nl;
2574 node_p node;
2575 int num = 0, i;
2576
2577 mtx_lock(&ng_namehash_mtx);
2578 /* Count number of nodes */
2579 for (i = 0; i < NG_NAME_HASH_SIZE; i++) {
2580 LIST_FOREACH(node, &ng_name_hash[i], nd_nodes) {
2581 if (NG_NODE_IS_VALID(node) &&
2582 (unnamed || NG_NODE_HAS_NAME(node))) {
2583 num++;
2584 }
2585 }
2586 }
2587 mtx_unlock(&ng_namehash_mtx);
2588
2589 /* Get response struct */
2590 NG_MKRESPONSE(resp, msg, sizeof(*nl)
5a975a3d 2591 + (num * sizeof(struct nodeinfo)), M_WAITOK | M_NULLOK);
b06ebda0
MD
2592 if (resp == NULL) {
2593 error = ENOMEM;
2594 break;
2595 }
2596 nl = (struct namelist *) resp->data;
2597
2598 /* Cycle through the linked list of nodes */
2599 nl->numnames = 0;
2600 mtx_lock(&ng_namehash_mtx);
2601 for (i = 0; i < NG_NAME_HASH_SIZE; i++) {
2602 LIST_FOREACH(node, &ng_name_hash[i], nd_nodes) {
2603 struct nodeinfo *const np =
2604 &nl->nodeinfo[nl->numnames];
2605
2606 if (NG_NODE_NOT_VALID(node))
2607 continue;
2608 if (!unnamed && (! NG_NODE_HAS_NAME(node)))
2609 continue;
2610 if (nl->numnames >= num) {
2611 log(LOG_ERR, "%s: number of nodes changed\n",
2612 __func__);
2613 break;
2614 }
2615 if (NG_NODE_HAS_NAME(node))
2616 strcpy(np->name, NG_NODE_NAME(node));
2617 strcpy(np->type, node->nd_type->name);
2618 np->id = ng_node2ID(node);
2619 np->hooks = node->nd_numhooks;
2620 nl->numnames++;
2621 }
2622 }
2623 mtx_unlock(&ng_namehash_mtx);
2624 break;
2625 }
2626
2627 case NGM_LISTTYPES:
2628 {
2629 struct typelist *tl;
2630 struct ng_type *type;
2631 int num = 0;
2632
2633 mtx_lock(&ng_typelist_mtx);
2634 /* Count number of types */
2635 LIST_FOREACH(type, &ng_typelist, types) {
2636 num++;
2637 }
2638 mtx_unlock(&ng_typelist_mtx);
2639
2640 /* Get response struct */
2641 NG_MKRESPONSE(resp, msg, sizeof(*tl)
5a975a3d 2642 + (num * sizeof(struct typeinfo)), M_WAITOK | M_NULLOK);
b06ebda0
MD
2643 if (resp == NULL) {
2644 error = ENOMEM;
2645 break;
2646 }
2647 tl = (struct typelist *) resp->data;
2648
2649 /* Cycle through the linked list of types */
2650 tl->numtypes = 0;
2651 mtx_lock(&ng_typelist_mtx);
2652 LIST_FOREACH(type, &ng_typelist, types) {
2653 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes];
2654
2655 if (tl->numtypes >= num) {
2656 log(LOG_ERR, "%s: number of %s changed\n",
2657 __func__, "types");
2658 break;
2659 }
2660 strcpy(tp->type_name, type->name);
2661 tp->numnodes = type->refs - 1; /* don't count list */
2662 tl->numtypes++;
2663 }
2664 mtx_unlock(&ng_typelist_mtx);
2665 break;
2666 }
2667
2668 case NGM_BINARY2ASCII:
2669 {
2670 int bufSize = 20 * 1024; /* XXX hard coded constant */
2671 const struct ng_parse_type *argstype;
2672 const struct ng_cmdlist *c;
2673 struct ng_mesg *binary, *ascii;
2674
2675 /* Data area must contain a valid netgraph message */
2676 binary = (struct ng_mesg *)msg->data;
2677 if (msg->header.arglen < sizeof(struct ng_mesg) ||
2678 (msg->header.arglen - sizeof(struct ng_mesg) <
2679 binary->header.arglen)) {
2680 TRAP_ERROR();
2681 error = EINVAL;
2682 break;
2683 }
2684
2685 /* Get a response message with lots of room */
5a975a3d 2686 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_WAITOK | M_NULLOK);
b06ebda0
MD
2687 if (resp == NULL) {
2688 error = ENOMEM;
2689 break;
2690 }
2691 ascii = (struct ng_mesg *)resp->data;
2692
2693 /* Copy binary message header to response message payload */
2694 bcopy(binary, ascii, sizeof(*binary));
2695
2696 /* Find command by matching typecookie and command number */
2697 for (c = here->nd_type->cmdlist;
2698 c != NULL && c->name != NULL; c++) {
2699 if (binary->header.typecookie == c->cookie
2700 && binary->header.cmd == c->cmd)
2701 break;
2702 }
2703 if (c == NULL || c->name == NULL) {
2704 for (c = ng_generic_cmds; c->name != NULL; c++) {
2705 if (binary->header.typecookie == c->cookie
2706 && binary->header.cmd == c->cmd)
2707 break;
2708 }
2709 if (c->name == NULL) {
2710 NG_FREE_MSG(resp);
2711 error = ENOSYS;
2712 break;
2713 }
2714 }
2715
2716 /* Convert command name to ASCII */
2717 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr),
2718 "%s", c->name);
2719
2720 /* Convert command arguments to ASCII */
2721 argstype = (binary->header.flags & NGF_RESP) ?
2722 c->respType : c->mesgType;
2723 if (argstype == NULL) {
2724 *ascii->data = '\0';
2725 } else {
2726 if ((error = ng_unparse(argstype,
2727 (u_char *)binary->data,
2728 ascii->data, bufSize)) != 0) {
2729 NG_FREE_MSG(resp);
2730 break;
2731 }
2732 }
2733
2734 /* Return the result as struct ng_mesg plus ASCII string */
2735 bufSize = strlen(ascii->data) + 1;
2736 ascii->header.arglen = bufSize;
2737 resp->header.arglen = sizeof(*ascii) + bufSize;
2738 break;
2739 }
2740
2741 case NGM_ASCII2BINARY:
2742 {
2743 int bufSize = 2000; /* XXX hard coded constant */
2744 const struct ng_cmdlist *c;
2745 const struct ng_parse_type *argstype;
2746 struct ng_mesg *ascii, *binary;
2747 int off = 0;
2748
2749 /* Data area must contain at least a struct ng_mesg + '\0' */
2750 ascii = (struct ng_mesg *)msg->data;
2751 if ((msg->header.arglen < sizeof(*ascii) + 1) ||
2752 (ascii->header.arglen < 1) ||
2753 (msg->header.arglen < sizeof(*ascii) +
2754 ascii->header.arglen)) {
2755 TRAP_ERROR();
2756 error = EINVAL;
2757 break;
2758 }
2759 ascii->data[ascii->header.arglen - 1] = '\0';
2760
2761 /* Get a response message with lots of room */
5a975a3d 2762 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_WAITOK | M_NULLOK);
b06ebda0
MD
2763 if (resp == NULL) {
2764 error = ENOMEM;
2765 break;
2766 }
2767 binary = (struct ng_mesg *)resp->data;
2768
2769 /* Copy ASCII message header to response message payload */
2770 bcopy(ascii, binary, sizeof(*ascii));
2771
2772 /* Find command by matching ASCII command string */
2773 for (c = here->nd_type->cmdlist;
2774 c != NULL && c->name != NULL; c++) {
2775 if (strcmp(ascii->header.cmdstr, c->name) == 0)
2776 break;
2777 }
2778 if (c == NULL || c->name == NULL) {
2779 for (c = ng_generic_cmds; c->name != NULL; c++) {
2780 if (strcmp(ascii->header.cmdstr, c->name) == 0)
2781 break;
2782 }
2783 if (c->name == NULL) {
2784 NG_FREE_MSG(resp);
2785 error = ENOSYS;
2786 break;
2787 }
2788 }
2789
2790 /* Convert command name to binary */
2791 binary->header.cmd = c->cmd;
2792 binary->header.typecookie = c->cookie;
2793
2794 /* Convert command arguments to binary */
2795 argstype = (binary->header.flags & NGF_RESP) ?
2796 c->respType : c->mesgType;
2797 if (argstype == NULL) {
2798 bufSize = 0;
2799 } else {
2800 if ((error = ng_parse(argstype, ascii->data,
2801 &off, (u_char *)binary->data, &bufSize)) != 0) {
2802 NG_FREE_MSG(resp);
2803 break;
2804 }
2805 }
2806
2807 /* Return the result */
2808 binary->header.arglen = bufSize;
2809 resp->header.arglen = sizeof(*binary) + bufSize;
2810 break;
2811 }
2812
2813 case NGM_TEXT_CONFIG:
2814 case NGM_TEXT_STATUS:
2815 /*
2816 * This one is tricky as it passes the command down to the
2817 * actual node, even though it is a generic type command.
2818 * This means we must assume that the item/msg is already freed
2819 * when control passes back to us.
2820 */
2821 if (here->nd_type->rcvmsg != NULL) {
2822 NGI_MSG(item) = msg; /* put it back as we found it */
2823 return((*here->nd_type->rcvmsg)(here, item, lasthook));
2824 }
2825 /* Fall through if rcvmsg not supported */
2826 default:
2827 TRAP_ERROR();
2828 error = EINVAL;
2829 }
2830 /*
2831 * Sometimes a generic message may be statically allocated
2832 * to avoid problems with allocating when in tight memeory situations.
2833 * Don't free it if it is so.
2834 * I break them appart here, because erros may cause a free if the item
2835 * in which case we'd be doing it twice.
2836 * they are kept together above, to simplify freeing.
2837 */
2838out:
2839 NG_RESPOND_MSG(error, here, item, resp);
2840 if (msg)
2841 NG_FREE_MSG(msg);
2842 return (error);
2843}
2844
2845/************************************************************************
2846 Queue element get/free routines
2847************************************************************************/
2848
2849uma_zone_t ng_qzone;
2850uma_zone_t ng_qdzone;
2851static int maxalloc = 4096;/* limit the damage of a leak */
2852static int maxdata = 512; /* limit the damage of a DoS */
2853
2854TUNABLE_INT("net.graph.maxalloc", &maxalloc);
2855SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc,
2856 0, "Maximum number of non-data queue items to allocate");
2857TUNABLE_INT("net.graph.maxdata", &maxdata);
2858SYSCTL_INT(_net_graph, OID_AUTO, maxdata, CTLFLAG_RDTUN, &maxdata,
2859 0, "Maximum number of data queue items to allocate");
2860
2861#ifdef NETGRAPH_DEBUG
2862static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist);
2863static int allocated; /* number of items malloc'd */
2864#endif
2865
2866/*
2867 * Get a queue entry.
2868 * This is usually called when a packet first enters netgraph.
2869 * By definition, this is usually from an interrupt, or from a user.
2870 * Users are not so important, but try be quick for the times that it's
2871 * an interrupt.
2872 */
2873static __inline item_p
2874ng_alloc_item(int type, int flags)
2875{
2876 item_p item;
2877
2878 KASSERT(((type & ~NGQF_TYPE) == 0),
2879 ("%s: incorrect item type: %d", __func__, type));
2880
2881 item = uma_zalloc((type == NGQF_DATA)?ng_qdzone:ng_qzone,
2882 ((flags & NG_WAITOK) ? M_WAITOK : M_NOWAIT) | M_ZERO);
2883
2884 if (item) {
2885 item->el_flags = type;
2886#ifdef NETGRAPH_DEBUG
2887 mtx_lock(&ngq_mtx);
2888 TAILQ_INSERT_TAIL(&ng_itemlist, item, all);
2889 allocated++;
2890 mtx_unlock(&ngq_mtx);
2891#endif
2892 }
2893
2894 return (item);
2895}
2896
2897/*
2898 * Release a queue entry
2899 */
2900void
2901ng_free_item(item_p item)
2902{
2903 /*
2904 * The item may hold resources on it's own. We need to free
2905 * these before we can free the item. What they are depends upon
2906 * what kind of item it is. it is important that nodes zero
2907 * out pointers to resources that they remove from the item
2908 * or we release them again here.
2909 */
2910 switch (item->el_flags & NGQF_TYPE) {
2911 case NGQF_DATA:
2912 /* If we have an mbuf still attached.. */
2913 NG_FREE_M(_NGI_M(item));
2914 break;
2915 case NGQF_MESG:
2916 _NGI_RETADDR(item) = 0;
2917 NG_FREE_MSG(_NGI_MSG(item));
2918 break;
2919 case NGQF_FN:
2920 case NGQF_FN2:
2921 /* nothing to free really, */
2922 _NGI_FN(item) = NULL;
2923 _NGI_ARG1(item) = NULL;
2924 _NGI_ARG2(item) = 0;
2925 break;
2926 }
2927 /* If we still have a node or hook referenced... */
2928 _NGI_CLR_NODE(item);
2929 _NGI_CLR_HOOK(item);
2930
2931#ifdef NETGRAPH_DEBUG
2932 mtx_lock(&ngq_mtx);
2933 TAILQ_REMOVE(&ng_itemlist, item, all);
2934 allocated--;
2935 mtx_unlock(&ngq_mtx);
2936#endif
2937 uma_zfree(((item->el_flags & NGQF_TYPE) == NGQF_DATA)?
2938 ng_qdzone:ng_qzone, item);
2939}
2940
2941/*
2942 * Change type of the queue entry.
2943 * Possibly reallocates it from another UMA zone.
2944 */
2945static __inline item_p
2946ng_realloc_item(item_p pitem, int type, int flags)
2947{
2948 item_p item;
2949 int from, to;
2950
2951 KASSERT((pitem != NULL), ("%s: can't reallocate NULL", __func__));
2952 KASSERT(((type & ~NGQF_TYPE) == 0),
2953 ("%s: incorrect item type: %d", __func__, type));
2954
2955 from = ((pitem->el_flags & NGQF_TYPE) == NGQF_DATA);
2956 to = (type == NGQF_DATA);
2957 if (from != to) {
2958 /* If reallocation is required do it and copy item. */
2959 if ((item = ng_alloc_item(type, flags)) == NULL) {
2960 ng_free_item(pitem);
2961 return (NULL);
2962 }
2963 *item = *pitem;
2964 ng_free_item(pitem);
2965 } else
2966 item = pitem;
2967 item->el_flags = (item->el_flags & ~NGQF_TYPE) | type;
2968
2969 return (item);
2970}
2971
2972/************************************************************************
2973 Module routines
2974************************************************************************/
2975
2976/*
2977 * Handle the loading/unloading of a netgraph node type module
2978 */
2979int
2980ng_mod_event(module_t mod, int event, void *data)
2981{
2982 struct ng_type *const type = data;
2983 int s, error = 0;
2984
2985 switch (event) {
2986 case MOD_LOAD:
2987
2988 /* Register new netgraph node type */
2989 s = splnet();
2990 if ((error = ng_newtype(type)) != 0) {
2991 splx(s);
2992 break;
2993 }
2994
2995 /* Call type specific code */
2996 if (type->mod_event != NULL)
2997 if ((error = (*type->mod_event)(mod, event, data))) {
2998 mtx_lock(&ng_typelist_mtx);
2999 type->refs--; /* undo it */
3000 LIST_REMOVE(type, types);
3001 mtx_unlock(&ng_typelist_mtx);
3002 }
3003 splx(s);
3004 break;
3005
3006 case MOD_UNLOAD:
3007 s = splnet();
3008 if (type->refs > 1) { /* make sure no nodes exist! */
3009 error = EBUSY;
3010 } else {
3011 if (type->refs == 0) {
3012 /* failed load, nothing to undo */
3013 splx(s);
3014 break;
3015 }
3016 if (type->mod_event != NULL) { /* check with type */
3017 error = (*type->mod_event)(mod, event, data);
3018 if (error != 0) { /* type refuses.. */
3019 splx(s);
3020 break;
3021 }
3022 }
3023 mtx_lock(&ng_typelist_mtx);
3024 LIST_REMOVE(type, types);
3025 mtx_unlock(&ng_typelist_mtx);
3026 }
3027 splx(s);
3028 break;
3029
3030 default:
3031 if (type->mod_event != NULL)
3032 error = (*type->mod_event)(mod, event, data);
3033 else
3034 error = EOPNOTSUPP; /* XXX ? */
3035 break;
3036 }
3037 return (error);
3038}
3039
3040/*
3041 * Handle loading and unloading for this code.
3042 * The only thing we need to link into is the NETISR strucure.
3043 */
3044static int
3045ngb_mod_event(module_t mod, int event, void *data)
3046{
3047 int error = 0;
3048
3049 switch (event) {
3050 case MOD_LOAD:
3051 /* Initialize everything. */
3052 NG_WORKLIST_LOCK_INIT();
3053 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL,
3054 MTX_DEF);
3055 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL,
3056 MTX_DEF);
3057 mtx_init(&ng_namehash_mtx, "netgraph namehash mutex", NULL,
3058 MTX_DEF);
3059 mtx_init(&ng_topo_mtx, "netgraph topology mutex", NULL,
3060 MTX_DEF);
3061#ifdef NETGRAPH_DEBUG
3062 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL,
3063 MTX_DEF);
3064 mtx_init(&ngq_mtx, "netgraph item list mutex", NULL,
3065 MTX_DEF);
3066#endif
3067 ng_qzone = uma_zcreate("NetGraph items", sizeof(struct ng_item),
3068 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0);
3069 uma_zone_set_max(ng_qzone, maxalloc);
3070 ng_qdzone = uma_zcreate("NetGraph data items", sizeof(struct ng_item),
3071 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0);
3072 uma_zone_set_max(ng_qdzone, maxdata);
c3c96e44 3073 netisr_register(NETISR_NETGRAPH, (netisr_t *)ngintr, NULL);
b06ebda0
MD
3074 break;
3075 case MOD_UNLOAD:
3076 /* You can't unload it because an interface may be using it. */
3077 error = EBUSY;
3078 break;
3079 default:
3080 error = EOPNOTSUPP;
3081 break;
3082 }
3083 return (error);
3084}
3085
3086static moduledata_t netgraph_mod = {
3087 "netgraph",
3088 ngb_mod_event,
3089 (NULL)
3090};
3091DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_MIDDLE);
3092SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family");
3093SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,"");
3094SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, "");
3095
3096#ifdef NETGRAPH_DEBUG
3097void
3098dumphook (hook_p hook, char *file, int line)
3099{
3100 printf("hook: name %s, %d refs, Last touched:\n",
3101 _NG_HOOK_NAME(hook), hook->hk_refs);
3102 printf(" Last active @ %s, line %d\n",
3103 hook->lastfile, hook->lastline);
3104 if (line) {
3105 printf(" problem discovered at file %s, line %d\n", file, line);
3106 }
3107}
3108
3109void
3110dumpnode(node_p node, char *file, int line)
3111{
3112 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n",
3113 _NG_NODE_ID(node), node->nd_type->name,
3114 node->nd_numhooks, node->nd_flags,
3115 node->nd_refs, node->nd_name);
3116 printf(" Last active @ %s, line %d\n",
3117 node->lastfile, node->lastline);
3118 if (line) {
3119 printf(" problem discovered at file %s, line %d\n", file, line);
3120 }
3121}
3122
3123void
3124dumpitem(item_p item, char *file, int line)
3125{
3126 printf(" ACTIVE item, last used at %s, line %d",
3127 item->lastfile, item->lastline);
3128 switch(item->el_flags & NGQF_TYPE) {
3129 case NGQF_DATA:
3130 printf(" - [data]\n");
3131 break;
3132 case NGQF_MESG:
3133 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item));
3134 break;
3135 case NGQF_FN:
3136 printf(" - fn@%p (%p, %p, %p, %d (%x))\n",
3137 _NGI_FN(item),
3138 _NGI_NODE(item),
3139 _NGI_HOOK(item),
3140 item->body.fn.fn_arg1,
3141 item->body.fn.fn_arg2,
3142 item->body.fn.fn_arg2);
3143 break;
3144 case NGQF_FN2:
3145 printf(" - fn2@%p (%p, %p, %p, %d (%x))\n",
3146 _NGI_FN2(item),
3147 _NGI_NODE(item),
3148 _NGI_HOOK(item),
3149 item->body.fn.fn_arg1,
3150 item->body.fn.fn_arg2,
3151 item->body.fn.fn_arg2);
3152 break;
3153 }
3154 if (line) {
3155 printf(" problem discovered at file %s, line %d\n", file, line);
3156 if (_NGI_NODE(item)) {
3157 printf("node %p ([%x])\n",
3158 _NGI_NODE(item), ng_node2ID(_NGI_NODE(item)));
3159 }
3160 }
3161}
3162
3163static void
3164ng_dumpitems(void)
3165{
3166 item_p item;
3167 int i = 1;
3168 TAILQ_FOREACH(item, &ng_itemlist, all) {
3169 printf("[%d] ", i++);
3170 dumpitem(item, NULL, 0);
3171 }
3172}
3173
3174static void
3175ng_dumpnodes(void)
3176{
3177 node_p node;
3178 int i = 1;
3179 mtx_lock(&ng_nodelist_mtx);
3180 SLIST_FOREACH(node, &ng_allnodes, nd_all) {
3181 printf("[%d] ", i++);
3182 dumpnode(node, NULL, 0);
3183 }
3184 mtx_unlock(&ng_nodelist_mtx);
3185}
3186
3187static void
3188ng_dumphooks(void)
3189{
3190 hook_p hook;
3191 int i = 1;
3192 mtx_lock(&ng_nodelist_mtx);
3193 SLIST_FOREACH(hook, &ng_allhooks, hk_all) {
3194 printf("[%d] ", i++);
3195 dumphook(hook, NULL, 0);
3196 }
3197 mtx_unlock(&ng_nodelist_mtx);
3198}
3199
3200static int
3201sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS)
3202{
3203 int error;
3204 int val;
3205 int i;
3206
3207 val = allocated;
3208 i = 1;
3209 error = sysctl_handle_int(oidp, &val, 0, req);
3210 if (error != 0 || req->newptr == NULL)
3211 return (error);
3212 if (val == 42) {
3213 ng_dumpitems();
3214 ng_dumpnodes();
3215 ng_dumphooks();
3216 }
3217 return (0);
3218}
3219
3220SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW,
3221 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items");
3222#endif /* NETGRAPH_DEBUG */
3223
3224
3225/***********************************************************************
3226* Worklist routines
3227**********************************************************************/
3228/* NETISR thread enters here */
3229/*
3230 * Pick a node off the list of nodes with work,
3231 * try get an item to process off it.
3232 * If there are no more, remove the node from the list.
3233 */
3234static void
3235ngintr(void)
3236{
c3c96e44 3237 XXX replymsg XXX
b06ebda0
MD
3238 for (;;) {
3239 node_p node;
3240
3241 /* Get node from the worklist. */
3242 NG_WORKLIST_LOCK();
3243 node = STAILQ_FIRST(&ng_worklist);
3244 if (!node) {
3245 NG_WORKLIST_UNLOCK();
3246 break;
3247 }
3248 STAILQ_REMOVE_HEAD(&ng_worklist, nd_input_queue.q_work);
3249 NG_WORKLIST_UNLOCK();
3250 CTR3(KTR_NET, "%20s: node [%x] (%p) taken off worklist",
3251 __func__, node->nd_ID, node);
3252 /*
3253 * We have the node. We also take over the reference
3254 * that the list had on it.
3255 * Now process as much as you can, until it won't
3256 * let you have another item off the queue.
3257 * All this time, keep the reference
3258 * that lets us be sure that the node still exists.
3259 * Let the reference go at the last minute.
3260 */
3261 for (;;) {
3262 item_p item;
3263 int rw;
3264
3265 NG_QUEUE_LOCK(&node->nd_input_queue);
3266 item = ng_dequeue(node, &rw);
3267 if (item == NULL) {
3268 node->nd_input_queue.q_flags2 &= ~NGQ2_WORKQ;
3269 NG_QUEUE_UNLOCK(&node->nd_input_queue);
3270 break; /* go look for another node */
3271 } else {
3272 NG_QUEUE_UNLOCK(&node->nd_input_queue);
3273 NGI_GET_NODE(item, node); /* zaps stored node */
3274 ng_apply_item(node, item, rw);
3275 NG_NODE_UNREF(node);
3276 }
3277 }
3278 NG_NODE_UNREF(node);
3279 }
3280}
3281
3282/*
3283 * XXX
3284 * It's posible that a debugging NG_NODE_REF may need
3285 * to be outside the mutex zone
3286 */
3287static void
3288ng_worklist_add(node_p node)
3289{
3290
3291 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED);
3292
3293 if ((node->nd_input_queue.q_flags2 & NGQ2_WORKQ) == 0) {
3294 /*
3295 * If we are not already on the work queue,
3296 * then put us on.
3297 */
3298 node->nd_input_queue.q_flags2 |= NGQ2_WORKQ;
3299 NG_NODE_REF(node); /* XXX fafe in mutex? */
3300 NG_WORKLIST_LOCK();
3301 STAILQ_INSERT_TAIL(&ng_worklist, node, nd_input_queue.q_work);
3302 NG_WORKLIST_UNLOCK();
3303 schednetisr(NETISR_NETGRAPH);
3304 CTR3(KTR_NET, "%20s: node [%x] (%p) put on worklist", __func__,
3305 node->nd_ID, node);
3306 } else {
3307 CTR3(KTR_NET, "%20s: node [%x] (%p) already on worklist",
3308 __func__, node->nd_ID, node);
3309 }
3310}
3311
3312
3313/***********************************************************************
3314* Externally useable functions to set up a queue item ready for sending
3315***********************************************************************/
3316
3317#ifdef NETGRAPH_DEBUG
3318#define ITEM_DEBUG_CHECKS \
3319 do { \
3320 if (NGI_NODE(item) ) { \
3321 printf("item already has node"); \
3322 kdb_enter(KDB_WHY_NETGRAPH, "has node"); \
3323 NGI_CLR_NODE(item); \
3324 } \
3325 if (NGI_HOOK(item) ) { \
3326 printf("item already has hook"); \
3327 kdb_enter(KDB_WHY_NETGRAPH, "has hook"); \
3328 NGI_CLR_HOOK(item); \
3329 } \
3330 } while (0)
3331#else
3332#define ITEM_DEBUG_CHECKS
3333#endif
3334
3335/*
3336 * Put mbuf into the item.
3337 * Hook and node references will be removed when the item is dequeued.
3338 * (or equivalent)
3339 * (XXX) Unsafe because no reference held by peer on remote node.
3340 * remote node might go away in this timescale.
3341 * We know the hooks can't go away because that would require getting
3342 * a writer item on both nodes and we must have at least a reader
3343 * here to be able to do this.
3344 * Note that the hook loaded is the REMOTE hook.
3345 *
3346 * This is possibly in the critical path for new data.
3347 */
3348item_p
3349ng_package_data(struct mbuf *m, int flags)
3350{
3351 item_p item;
3352
3353 if ((item = ng_alloc_item(NGQF_DATA, flags)) == NULL) {
3354 NG_FREE_M(m);
3355 return (NULL);
3356 }
3357 ITEM_DEBUG_CHECKS;
3358 item->el_flags |= NGQF_READER;
3359 NGI_M(item) = m;
3360 return (item);
3361}
3362
3363/*
3364 * Allocate a queue item and put items into it..
3365 * Evaluate the address as this will be needed to queue it and
3366 * to work out what some of the fields should be.
3367 * Hook and node references will be removed when the item is dequeued.
3368 * (or equivalent)
3369 */
3370item_p
3371ng_package_msg(struct ng_mesg *msg, int flags)
3372{
3373 item_p item;
3374
3375 if ((item = ng_alloc_item(NGQF_MESG, flags)) == NULL) {
3376 NG_FREE_MSG(msg);
3377 return (NULL);
3378 }
3379 ITEM_DEBUG_CHECKS;
3380 /* Messages items count as writers unless explicitly exempted. */
3381 if (msg->header.cmd & NGM_READONLY)
3382 item->el_flags |= NGQF_READER;
3383 else
3384 item->el_flags |= NGQF_WRITER;
3385 /*
3386 * Set the current lasthook into the queue item
3387 */
3388 NGI_MSG(item) = msg;
3389 NGI_RETADDR(item) = 0;
3390 return (item);
3391}
3392
3393
3394
3395#define SET_RETADDR(item, here, retaddr) \
3396 do { /* Data or fn items don't have retaddrs */ \
3397 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \
3398 if (retaddr) { \
3399 NGI_RETADDR(item) = retaddr; \
3400 } else { \
3401 /* \
3402 * The old return address should be ok. \
3403 * If there isn't one, use the address \
3404 * here. \
3405 */ \
3406 if (NGI_RETADDR(item) == 0) { \
3407 NGI_RETADDR(item) \
3408 = ng_node2ID(here); \
3409 } \
3410 } \
3411 } \
3412 } while (0)
3413
3414int
3415ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr)
3416{
3417 hook_p peer;
3418 node_p peernode;
3419 ITEM_DEBUG_CHECKS;
3420 /*
3421 * Quick sanity check..
3422 * Since a hook holds a reference on it's node, once we know
3423 * that the peer is still connected (even if invalid,) we know
3424 * that the peer node is present, though maybe invalid.
3425 */
3426 if ((hook == NULL) ||
3427 NG_HOOK_NOT_VALID(hook) ||
3428 NG_HOOK_NOT_VALID(peer = NG_HOOK_PEER(hook)) ||
3429 NG_NODE_NOT_VALID(peernode = NG_PEER_NODE(hook))) {
3430 NG_FREE_ITEM(item);
3431 TRAP_ERROR();
3432 return (ENETDOWN);
3433 }
3434
3435 /*
3436 * Transfer our interest to the other (peer) end.
3437 */
3438 NG_HOOK_REF(peer);
3439 NG_NODE_REF(peernode);
3440 NGI_SET_HOOK(item, peer);
3441 NGI_SET_NODE(item, peernode);
3442 SET_RETADDR(item, here, retaddr);
3443 return (0);
3444}
3445
3446int
3447ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr)
3448{
3449 node_p dest = NULL;
3450 hook_p hook = NULL;
3451 int error;
3452
3453 ITEM_DEBUG_CHECKS;
3454 /*
3455 * Note that ng_path2noderef increments the reference count
3456 * on the node for us if it finds one. So we don't have to.
3457 */
3458 error = ng_path2noderef(here, address, &dest, &hook);
3459 if (error) {
3460 NG_FREE_ITEM(item);
3461 return (error);
3462 }
3463 NGI_SET_NODE(item, dest);
3464 if ( hook) {
3465 NG_HOOK_REF(hook); /* don't let it go while on the queue */
3466 NGI_SET_HOOK(item, hook);
3467 }
3468 SET_RETADDR(item, here, retaddr);
3469 return (0);
3470}
3471
3472int
3473ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr)
3474{
3475 node_p dest;
3476
3477 ITEM_DEBUG_CHECKS;
3478 /*
3479 * Find the target node.
3480 */
3481 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */
3482 if (dest == NULL) {
3483 NG_FREE_ITEM(item);
3484 TRAP_ERROR();
3485 return(EINVAL);
3486 }
3487 /* Fill out the contents */
3488 NGI_SET_NODE(item, dest);
3489 NGI_CLR_HOOK(item);
3490 SET_RETADDR(item, here, retaddr);
3491 return (0);
3492}
3493
3494/*
3495 * special case to send a message to self (e.g. destroy node)
3496 * Possibly indicate an arrival hook too.
3497 * Useful for removing that hook :-)
3498 */
3499item_p
3500ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg)
3501{
3502 item_p item;
3503
3504 /*
3505 * Find the target node.
3506 * If there is a HOOK argument, then use that in preference
3507 * to the address.
3508 */
3509 if ((item = ng_alloc_item(NGQF_MESG, NG_NOFLAGS)) == NULL) {
3510 NG_FREE_MSG(msg);
3511 return (NULL);
3512 }
3513
3514 /* Fill out the contents */
3515 item->el_flags |= NGQF_WRITER;
3516 NG_NODE_REF(here);
3517 NGI_SET_NODE(item, here);
3518 if (hook) {
3519 NG_HOOK_REF(hook);
3520 NGI_SET_HOOK(item, hook);
3521 }
3522 NGI_MSG(item) = msg;
3523 NGI_RETADDR(item) = ng_node2ID(here);
3524 return (item);
3525}
3526
3527/*
3528 * Send ng_item_fn function call to the specified node.
3529 */
3530
3531int
3532ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2)
3533{
3534
3535 return ng_send_fn1(node, hook, fn, arg1, arg2, NG_NOFLAGS);
3536}
3537
3538int
3539ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2,
3540 int flags)
3541{
3542 item_p item;
3543
3544 if ((item = ng_alloc_item(NGQF_FN, flags)) == NULL) {
3545 return (ENOMEM);
3546 }
3547 item->el_flags |= NGQF_WRITER;
3548 NG_NODE_REF(node); /* and one for the item */
3549 NGI_SET_NODE(item, node);
3550 if (hook) {
3551 NG_HOOK_REF(hook);
3552 NGI_SET_HOOK(item, hook);
3553 }
3554 NGI_FN(item) = fn;
3555 NGI_ARG1(item) = arg1;
3556 NGI_ARG2(item) = arg2;
3557 return(ng_snd_item(item, flags));
3558}
3559
3560/*
3561 * Send ng_item_fn2 function call to the specified node.
3562 *
3563 * If an optional pitem parameter is supplied, its apply
3564 * callback will be copied to the new item. If also NG_REUSE_ITEM
3565 * flag is set, no new item will be allocated, but pitem will
3566 * be used.
3567 */
3568int
3569ng_send_fn2(node_p node, hook_p hook, item_p pitem, ng_item_fn2 *fn, void *arg1,
3570 int arg2, int flags)
3571{
3572 item_p item;
3573
3574 KASSERT((pitem != NULL || (flags & NG_REUSE_ITEM) == 0),
3575 ("%s: NG_REUSE_ITEM but no pitem", __func__));
3576
3577 /*
3578 * Allocate a new item if no supplied or
3579 * if we can't use supplied one.
3580 */
3581 if (pitem == NULL || (flags & NG_REUSE_ITEM) == 0) {
3582 if ((item = ng_alloc_item(NGQF_FN2, flags)) == NULL)
3583 return (ENOMEM);
3584 if (pitem != NULL)
3585 item->apply = pitem->apply;
3586 } else {
3587 if ((item = ng_realloc_item(pitem, NGQF_FN2, flags)) == NULL)
3588 return (ENOMEM);
3589 }
3590
3591 item->el_flags = (item->el_flags & ~NGQF_RW) | NGQF_WRITER;
3592 NG_NODE_REF(node); /* and one for the item */
3593 NGI_SET_NODE(item, node);
3594 if (hook) {
3595 NG_HOOK_REF(hook);
3596 NGI_SET_HOOK(item, hook);
3597 }
3598 NGI_FN2(item) = fn;
3599 NGI_ARG1(item) = arg1;
3600 NGI_ARG2(item) = arg2;
3601 return(ng_snd_item(item, flags));
3602}
3603
3604/*
3605 * Official timeout routines for Netgraph nodes.
3606 */
3607static void
3608ng_callout_trampoline(void *arg)
3609{
3610 item_p item = arg;
3611
3612 ng_snd_item(item, 0);
3613}
3614
3615
3616int
3617ng_callout(struct callout *c, node_p node, hook_p hook, int ticks,
3618 ng_item_fn *fn, void * arg1, int arg2)
3619{
3620 item_p item, oitem;
3621
3622 if ((item = ng_alloc_item(NGQF_FN, NG_NOFLAGS)) == NULL)
3623 return (ENOMEM);
3624
3625 item->el_flags |= NGQF_WRITER;
3626 NG_NODE_REF(node); /* and one for the item */
3627 NGI_SET_NODE(item, node);
3628 if (hook) {
3629 NG_HOOK_REF(hook);
3630 NGI_SET_HOOK(item, hook);
3631 }
3632 NGI_FN(item) = fn;
3633 NGI_ARG1(item) = arg1;
3634 NGI_ARG2(item) = arg2;
3635 oitem = c->c_arg;
3636 if (callout_reset(c, ticks, &ng_callout_trampoline, item) == 1 &&
3637 oitem != NULL)
3638 NG_FREE_ITEM(oitem);
3639 return (0);
3640}
3641
3642/* A special modified version of untimeout() */
3643int
3644ng_uncallout(struct callout *c, node_p node)
3645{
3646 item_p item;
3647 int rval;
3648
3649 KASSERT(c != NULL, ("ng_uncallout: NULL callout"));
3650 KASSERT(node != NULL, ("ng_uncallout: NULL node"));
3651
3652 rval = callout_stop(c);
3653 item = c->c_arg;
3654 /* Do an extra check */
3655 if ((rval > 0) && (c->c_func == &ng_callout_trampoline) &&
3656 (NGI_NODE(item) == node)) {
3657 /*
3658 * We successfully removed it from the queue before it ran
3659 * So now we need to unreference everything that was
3660 * given extra references. (NG_FREE_ITEM does this).
3661 */
3662 NG_FREE_ITEM(item);
3663 }
3664 c->c_arg = NULL;
3665
3666 return (rval);
3667}
3668
3669/*
3670 * Set the address, if none given, give the node here.
3671 */
3672void
3673ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr)
3674{
3675 if (retaddr) {
3676 NGI_RETADDR(item) = retaddr;
3677 } else {
3678 /*
3679 * The old return address should be ok.
3680 * If there isn't one, use the address here.
3681 */
3682 NGI_RETADDR(item) = ng_node2ID(here);
3683 }
3684}
3685
3686#define TESTING
3687#ifdef TESTING
3688/* just test all the macros */
3689void
3690ng_macro_test(item_p item);
3691void
3692ng_macro_test(item_p item)
3693{
3694 node_p node = NULL;
3695 hook_p hook = NULL;
3696 struct mbuf *m;
3697 struct ng_mesg *msg;
3698 ng_ID_t retaddr;
3699 int error;
3700
3701 NGI_GET_M(item, m);
3702 NGI_GET_MSG(item, msg);
3703 retaddr = NGI_RETADDR(item);
3704 NG_SEND_DATA(error, hook, m, NULL);
3705 NG_SEND_DATA_ONLY(error, hook, m);
3706 NG_FWD_NEW_DATA(error, item, hook, m);
3707 NG_FWD_ITEM_HOOK(error, item, hook);
3708 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr);
3709 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr);
3710 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr);
3711 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr);
3712}
3713#endif /* TESTING */
3714