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 /*
28 * Active walks are tracked using a WCB (Walk Control Block), which is a simple
29 * data structure that contains the mdb_walk_state_t passed to the various
30 * walker functions for this particular walk, as well as links to other walk
31 * layers if this is a layered walk. The control block is kept in a list
32 * associated with the MDB frame, so that we can clean up all the walks and
33 * call their respective fini routines at the end of command processing.
34 */
35
36 #include <mdb/mdb_module.h>
37 #include <mdb/mdb_modapi.h>
38 #include <mdb/mdb_debug.h>
39 #include <mdb/mdb_frame.h>
40 #include <mdb/mdb_err.h>
41 #include <mdb/mdb_wcb.h>
42 #include <mdb/mdb.h>
43
44 mdb_wcb_t *
mdb_wcb_from_state(mdb_walk_state_t * wsp)45 mdb_wcb_from_state(mdb_walk_state_t *wsp)
46 {
47 /*
48 * The walk state passed to a walker sits at the start of the
49 * walk control block, so we can ask the walker to pass this
50 * back to us and quickly obtain the control block:
51 */
52 mdb_wcb_t *wcb = (mdb_wcb_t *)wsp;
53
54 if (wcb->w_buftag != WCB_TAG_ACTIVE && wcb->w_buftag != WCB_TAG_INITIAL)
55 fail("walk state %p is corrupt or not active\n", (void *)wcb);
56
57 return (wcb);
58 }
59
60 mdb_wcb_t *
mdb_wcb_create(mdb_iwalker_t * iwp,mdb_walk_cb_t cb,void * data,uintptr_t addr)61 mdb_wcb_create(mdb_iwalker_t *iwp, mdb_walk_cb_t cb, void *data, uintptr_t addr)
62 {
63 mdb_wcb_t *wcb = mdb_zalloc(sizeof (mdb_wcb_t), UM_SLEEP);
64
65 wcb->w_buftag = WCB_TAG_INITIAL;
66 wcb->w_walker = iwp;
67
68 wcb->w_state.walk_callback = cb;
69 wcb->w_state.walk_cbdata = data;
70 wcb->w_state.walk_addr = addr;
71 wcb->w_state.walk_arg = iwp->iwlk_init_arg;
72
73 return (wcb);
74 }
75
76 void
mdb_wcb_destroy(mdb_wcb_t * wcb)77 mdb_wcb_destroy(mdb_wcb_t *wcb)
78 {
79 mdb_wcb_t *p, *q;
80
81 for (p = wcb->w_lyr_head; p != NULL; p = q) {
82 q = wcb->w_lyr_link;
83 mdb_wcb_destroy(p);
84 }
85
86 if (wcb->w_inited)
87 wcb->w_walker->iwlk_fini(&wcb->w_state);
88
89 mdb_free(wcb, sizeof (mdb_wcb_t));
90 }
91
92 void
mdb_wcb_insert(mdb_wcb_t * wcb,mdb_frame_t * fp)93 mdb_wcb_insert(mdb_wcb_t *wcb, mdb_frame_t *fp)
94 {
95 mdb_dprintf(MDB_DBG_WALK, "activate walk %s`%s wcb %p\n",
96 wcb->w_walker->iwlk_modp->mod_name,
97 wcb->w_walker->iwlk_name, (void *)wcb);
98
99 wcb->w_buftag = WCB_TAG_ACTIVE;
100 wcb->w_link = fp->f_wcbs;
101 fp->f_wcbs = wcb;
102 }
103
104 void
mdb_wcb_delete(mdb_wcb_t * wcb,mdb_frame_t * fp)105 mdb_wcb_delete(mdb_wcb_t *wcb, mdb_frame_t *fp)
106 {
107 mdb_wcb_t **pp = &fp->f_wcbs;
108 mdb_wcb_t *w;
109
110 mdb_dprintf(MDB_DBG_WALK, "deactivate walk %s`%s wcb %p\n",
111 wcb->w_walker->iwlk_modp->mod_name,
112 wcb->w_walker->iwlk_name, (void *)wcb);
113
114 for (w = fp->f_wcbs; w != NULL; pp = &w->w_link, w = w->w_link) {
115 if (w == wcb) {
116 w->w_buftag = WCB_TAG_PASSIVE;
117 *pp = w->w_link;
118 return;
119 }
120 }
121
122 fail("attempted to remove wcb not on list: %p\n", (void *)wcb);
123 }
124
125 void
mdb_wcb_purge(mdb_wcb_t ** wcbpp)126 mdb_wcb_purge(mdb_wcb_t **wcbpp)
127 {
128 mdb_wcb_t *n, *wcb = *wcbpp;
129
130 while (wcb != NULL) {
131 mdb_dprintf(MDB_DBG_WALK, "purge walk %s`%s wcb %p\n",
132 wcb->w_walker->iwlk_modp->mod_name,
133 wcb->w_walker->iwlk_name, (void *)wcb);
134
135 n = wcb->w_link;
136 mdb_wcb_destroy(wcb);
137 wcb = n;
138 }
139
140 *wcbpp = NULL;
141 }
142