xref: /titanic_41/usr/src/cmd/mdb/common/mdb/mdb_wcb.c (revision 7c478bd95313f5f23a4c958a745db2134aa03244)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 /*
30  * Active walks are tracked using a WCB (Walk Control Block), which is a simple
31  * data structure that contains the mdb_walk_state_t passed to the various
32  * walker functions for this particular walk, as well as links to other walk
33  * layers if this is a layered walk.  The control block is kept in a list
34  * associated with the MDB frame, so that we can clean up all the walks and
35  * call their respective fini routines at the end of command processing.
36  */
37 
38 #include <mdb/mdb_module.h>
39 #include <mdb/mdb_modapi.h>
40 #include <mdb/mdb_debug.h>
41 #include <mdb/mdb_frame.h>
42 #include <mdb/mdb_err.h>
43 #include <mdb/mdb_wcb.h>
44 #include <mdb/mdb.h>
45 
46 mdb_wcb_t *
mdb_wcb_from_state(mdb_walk_state_t * wsp)47 mdb_wcb_from_state(mdb_walk_state_t *wsp)
48 {
49 	/*
50 	 * The walk state passed to a walker sits at the start of the
51 	 * walk control block, so we can ask the walker to pass this
52 	 * back to us and quickly obtain the control block:
53 	 */
54 	mdb_wcb_t *wcb = (mdb_wcb_t *)wsp;
55 
56 	if (wcb->w_buftag != WCB_TAG_ACTIVE && wcb->w_buftag != WCB_TAG_INITIAL)
57 		fail("walk state %p is corrupt or not active\n", (void *)wcb);
58 
59 	return (wcb);
60 }
61 
62 mdb_wcb_t *
mdb_wcb_create(mdb_iwalker_t * iwp,mdb_walk_cb_t cb,void * data,uintptr_t addr)63 mdb_wcb_create(mdb_iwalker_t *iwp, mdb_walk_cb_t cb, void *data, uintptr_t addr)
64 {
65 	mdb_wcb_t *wcb = mdb_zalloc(sizeof (mdb_wcb_t), UM_SLEEP);
66 
67 	wcb->w_buftag = WCB_TAG_INITIAL;
68 	wcb->w_walker = iwp;
69 
70 	wcb->w_state.walk_callback = cb;
71 	wcb->w_state.walk_cbdata = data;
72 	wcb->w_state.walk_addr = addr;
73 	wcb->w_state.walk_arg = iwp->iwlk_init_arg;
74 
75 	return (wcb);
76 }
77 
78 void
mdb_wcb_destroy(mdb_wcb_t * wcb)79 mdb_wcb_destroy(mdb_wcb_t *wcb)
80 {
81 	mdb_wcb_t *p, *q;
82 
83 	for (p = wcb->w_lyr_head; p != NULL; p = q) {
84 		q = wcb->w_lyr_link;
85 		mdb_wcb_destroy(p);
86 	}
87 
88 	if (wcb->w_inited)
89 		wcb->w_walker->iwlk_fini(&wcb->w_state);
90 
91 	mdb_free(wcb, sizeof (mdb_wcb_t));
92 }
93 
94 void
mdb_wcb_insert(mdb_wcb_t * wcb,mdb_frame_t * fp)95 mdb_wcb_insert(mdb_wcb_t *wcb, mdb_frame_t *fp)
96 {
97 	mdb_dprintf(MDB_DBG_WALK, "activate walk %s`%s wcb %p\n",
98 	    wcb->w_walker->iwlk_modp->mod_name,
99 	    wcb->w_walker->iwlk_name, (void *)wcb);
100 
101 	wcb->w_buftag = WCB_TAG_ACTIVE;
102 	wcb->w_link = fp->f_wcbs;
103 	fp->f_wcbs = wcb;
104 }
105 
106 void
mdb_wcb_delete(mdb_wcb_t * wcb,mdb_frame_t * fp)107 mdb_wcb_delete(mdb_wcb_t *wcb, mdb_frame_t *fp)
108 {
109 	mdb_wcb_t **pp = &fp->f_wcbs;
110 	mdb_wcb_t *w;
111 
112 	mdb_dprintf(MDB_DBG_WALK, "deactivate walk %s`%s wcb %p\n",
113 	    wcb->w_walker->iwlk_modp->mod_name,
114 	    wcb->w_walker->iwlk_name, (void *)wcb);
115 
116 	for (w = fp->f_wcbs; w != NULL; pp = &w->w_link, w = w->w_link) {
117 		if (w == wcb) {
118 			w->w_buftag = WCB_TAG_PASSIVE;
119 			*pp = w->w_link;
120 			return;
121 		}
122 	}
123 
124 	fail("attempted to remove wcb not on list: %p\n", (void *)wcb);
125 }
126 
127 void
mdb_wcb_purge(mdb_wcb_t ** wcbpp)128 mdb_wcb_purge(mdb_wcb_t **wcbpp)
129 {
130 	mdb_wcb_t *n, *wcb = *wcbpp;
131 
132 	while (wcb != NULL) {
133 		mdb_dprintf(MDB_DBG_WALK, "purge walk %s`%s wcb %p\n",
134 		    wcb->w_walker->iwlk_modp->mod_name,
135 		    wcb->w_walker->iwlk_name, (void *)wcb);
136 
137 		n = wcb->w_link;
138 		mdb_wcb_destroy(wcb);
139 		wcb = n;
140 	}
141 
142 	*wcbpp = NULL;
143 }
144