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 2006 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 #include <sys/param.h>
28 #include <sys/modctl.h>
29 #include <sys/kobj.h>
30 #include <sys/kobj_impl.h>
31 #include <unistd.h>
32 #include <strings.h>
33 #include <dlfcn.h>
34 #include <link.h>
35
36 #include <kmdb/kmdb_module.h>
37 #include <kmdb/kmdb_wr_impl.h>
38 #include <kmdb/kmdb_kdi.h>
39 #include <mdb/mdb_modapi.h>
40 #include <mdb/mdb_debug.h>
41 #include <mdb/mdb_string.h>
42 #include <mdb/mdb_ctf.h>
43 #include <mdb/mdb_err.h>
44 #include <mdb/mdb_io.h>
45 #include <mdb/mdb_frame.h>
46 #include <mdb/mdb.h>
47
48 static void kmdb_module_request_unload(kmdb_modctl_t *, const char *, int);
49
50 static void
kmc_free(kmdb_modctl_t * kmc)51 kmc_free(kmdb_modctl_t *kmc)
52 {
53 if (kmc->kmc_modname != NULL)
54 strfree(kmc->kmc_modname);
55 mdb_free(kmc, sizeof (kmdb_modctl_t));
56 }
57
58 /*
59 * Sends a request to the driver to load the module. If/when the load has
60 * completed successfully, kmdb_module_loaded is called.
61 */
62 int
mdb_module_load(const char * fname,int mode)63 mdb_module_load(const char *fname, int mode)
64 {
65 const char *modname = strbasename(fname);
66 kmdb_wr_load_t *dlr;
67 kmdb_modctl_t *kmc = NULL;
68 const char *wformat = NULL;
69 mdb_var_t *v;
70
71 if (!mdb_module_validate_name(modname, &wformat))
72 goto module_load_err;
73
74 if ((v = mdb_nv_lookup(&mdb.m_dmodctl, modname)) != NULL) {
75 kmc = MDB_NV_COOKIE(v);
76
77 if (kmc->kmc_state == KMDB_MC_STATE_LOADING)
78 wformat = "module %s is already being loaded\n";
79 else
80 wformat = "module %s is being unloaded\n";
81 goto module_load_err;
82 }
83
84 kmc = mdb_zalloc(sizeof (kmdb_modctl_t), UM_SLEEP);
85 kmc->kmc_loadmode = mode;
86 kmc->kmc_modname = strdup(modname);
87 kmc->kmc_state = KMDB_MC_STATE_LOADING;
88
89 if (mdb_nv_insert(&mdb.m_dmodctl, modname, NULL, (uintptr_t)kmc, 0) ==
90 NULL) {
91 wformat = "module %s can't be registered for load\n";
92 kmc_free(kmc);
93 goto module_load_err;
94 }
95
96 dlr = mdb_zalloc(sizeof (kmdb_wr_load_t), UM_SLEEP);
97 dlr->dlr_node.wn_task = WNTASK_DMOD_LOAD;
98 dlr->dlr_fname = strdup(fname);
99
100 kmdb_wr_driver_notify(dlr);
101
102 if (!(mode & MDB_MOD_DEFER) &&
103 mdb_tgt_continue(mdb.m_target, NULL) == 0)
104 return (0);
105
106 if (!(mode & MDB_MOD_SILENT))
107 mdb_printf("%s load pending (:c to complete)\n", modname);
108
109 return (0);
110
111 module_load_err:
112 if (!(mode & MDB_MOD_SILENT))
113 warn(wformat, modname);
114
115 return (-1);
116 }
117
118 int
kmdb_module_loaded(kmdb_wr_load_t * dlr)119 kmdb_module_loaded(kmdb_wr_load_t *dlr)
120 {
121 struct modctl *modp = dlr->dlr_modctl;
122 const char *modname = strbasename(dlr->dlr_fname);
123 struct module *mp;
124 kmdb_modctl_t *kmc = NULL;
125 mdb_var_t *v;
126
127 v = mdb_nv_lookup(&mdb.m_dmodctl, modname);
128
129 if (dlr->dlr_errno != 0) {
130 /*
131 * We're somewhat limited in the diagnostics that we can
132 * provide in the event of a failed load. In most load-failure
133 * cases, the driver can only send up a generic errno. We use
134 * EMDB_ENOMOD to signal generic errors, and supply our own
135 * message. This twists the meaning of EMDB_NOMOD somewhat, but
136 * it's better than defining a new one.
137 */
138 if (dlr->dlr_errno == EMDB_NOMOD) {
139 mdb_warn("%s does not appear to be a kmdb dmod\n",
140 modname);
141 } else {
142 (void) set_errno(dlr->dlr_errno);
143 mdb_warn("dmod %s failed to load", modname);
144 }
145
146 if (v != NULL)
147 mdb_nv_remove(&mdb.m_dmodctl, v);
148 return (0);
149 }
150
151 if ((mp = modp->mod_mp) == NULL || mp->symhdr == NULL ||
152 mp->strhdr == NULL || mp->symtbl == NULL || mp->strings == NULL) {
153 mdb_warn("dmod %s did not load properly\n");
154 goto module_loaded_err;
155 }
156
157 if ((v = mdb_nv_lookup(&mdb.m_dmodctl, modname)) == NULL) {
158 kmc = mdb_zalloc(sizeof (kmdb_modctl_t), UM_SLEEP);
159 kmc->kmc_loadmode = MDB_MOD_LOCAL;
160 kmc->kmc_modname = strdup(modname);
161 kmc->kmc_state = KMDB_MC_STATE_LOADING;
162
163 (void) mdb_nv_insert(&mdb.m_dmodctl, modname, NULL,
164 (uintptr_t)kmc, 0);
165 } else {
166 kmc = MDB_NV_COOKIE(v);
167 ASSERT(kmc->kmc_symtab == NULL);
168 }
169
170 kmc->kmc_modctl = modp;
171 kmc->kmc_exported = (mp->flags & KOBJ_EXPORTED) != 0;
172 mdb_gelf_ehdr_to_gehdr(&mp->hdr, &kmc->kmc_ehdr);
173
174 kmc->kmc_symtab = mdb_gelf_symtab_create_raw(&kmc->kmc_ehdr, mp->symhdr,
175 mp->symtbl, mp->strhdr, mp->strings,
176 MDB_TGT_SYMTAB);
177
178 if (mp->flags & KOBJ_PRIM)
179 kmc->kmc_flags |= KMDB_MC_FL_NOUNLOAD;
180
181 if (mdb_module_create(modname, modp->mod_filename,
182 kmc->kmc_loadmode, &kmc->kmc_mod) < 0)
183 goto module_loaded_err;
184
185 kmc->kmc_state = KMDB_MC_STATE_LOADED;
186
187 return (1);
188
189 module_loaded_err:
190 if (kmc->kmc_symtab != NULL)
191 mdb_gelf_symtab_destroy(kmc->kmc_symtab);
192
193 kmdb_module_request_unload(kmc, kmc->kmc_modname, MDB_MOD_DEFER);
194 return (0);
195 }
196
197 void
kmdb_module_load_ack(kmdb_wr_load_t * dlr)198 kmdb_module_load_ack(kmdb_wr_load_t *dlr)
199 {
200 strfree(dlr->dlr_fname);
201 mdb_free(dlr, sizeof (kmdb_wr_load_t));
202 }
203
204 void
mdb_module_load_all(int mode)205 mdb_module_load_all(int mode)
206 {
207 kmdb_wr_t *wn;
208
209 ASSERT(mode & MDB_MOD_DEFER);
210
211 wn = mdb_zalloc(sizeof (kmdb_wr_t), UM_SLEEP);
212 wn->wn_task = WNTASK_DMOD_LOAD_ALL;
213
214 kmdb_wr_driver_notify(wn);
215 }
216
217 void
kmdb_module_load_all_ack(kmdb_wr_t * wn)218 kmdb_module_load_all_ack(kmdb_wr_t *wn)
219 {
220 mdb_free(wn, sizeof (kmdb_wr_t));
221 }
222
223 static void
kmdb_module_request_unload(kmdb_modctl_t * kmc,const char * modname,int mode)224 kmdb_module_request_unload(kmdb_modctl_t *kmc, const char *modname, int mode)
225 {
226 kmdb_wr_unload_t *dur = mdb_zalloc(sizeof (kmdb_wr_unload_t), UM_SLEEP);
227 dur->dur_node.wn_task = WNTASK_DMOD_UNLOAD;
228 dur->dur_modname = strdup(modname);
229 dur->dur_modctl = kmc->kmc_modctl;
230
231 kmdb_wr_driver_notify(dur);
232
233 kmc->kmc_state = KMDB_MC_STATE_UNLOADING;
234
235 if (!(mode & MDB_MOD_DEFER) &&
236 mdb_tgt_continue(mdb.m_target, NULL) == 0)
237 return;
238
239 if (!(mode & MDB_MOD_SILENT))
240 mdb_printf("%s unload pending (:c to complete)\n", modname);
241 }
242
243 /*ARGSUSED*/
244 int
mdb_module_unload(const char * name,int mode)245 mdb_module_unload(const char *name, int mode)
246 {
247 kmdb_modctl_t *kmc = NULL;
248 const char *basename;
249 mdb_var_t *v;
250
251 /*
252 * We may have been called with the name from the module itself
253 * if the caller is iterating through the module list, so we need
254 * to make a copy of the name. If we don't, we can't use it after
255 * the call to unload_common(), which frees the module.
256 */
257 name = strdup(name);
258 basename = strbasename(name);
259
260 /*
261 * Make sure the module is in the proper state for unloading. Modules
262 * may only be unloaded if they have properly completed loading.
263 */
264 if ((v = mdb_nv_lookup(&mdb.m_dmodctl, basename)) != NULL) {
265 kmc = MDB_NV_COOKIE(v);
266 switch (kmc->kmc_state) {
267 case KMDB_MC_STATE_LOADING:
268 warn("%s is in the process of loading\n", basename);
269 return (set_errno(EMDB_NOMOD));
270 case KMDB_MC_STATE_UNLOADING:
271 warn("%s is already being unloaded\n", basename);
272 return (set_errno(EMDB_NOMOD));
273 default:
274 ASSERT(kmc->kmc_state == KMDB_MC_STATE_LOADED);
275 }
276
277 if (kmc->kmc_flags & KMDB_MC_FL_NOUNLOAD)
278 return (set_errno(EMDB_KMODNOUNLOAD));
279 }
280
281 if (mdb_module_unload_common(name) < 0) {
282 if (!(mode & MDB_MOD_SILENT)) {
283 mdb_dprintf(MDB_DBG_MODULE, "unload of %s failed\n",
284 name);
285 }
286 return (-1); /* errno is set for us */
287 }
288
289 /*
290 * Any modules legitimately not listed in dmodctl (builtins, for
291 * example) will be handled by mdb_module_unload_common. If any of
292 * them get here, we've got a problem.
293 */
294 if (v == NULL) {
295 warn("unload of unregistered module %s\n", basename);
296 return (set_errno(EMDB_NOMOD));
297 }
298
299 ASSERT(kmc->kmc_dlrefcnt == 0);
300
301 mdb_gelf_symtab_destroy(kmc->kmc_symtab);
302
303 kmdb_module_request_unload(kmc, basename, mode);
304 return (0);
305 }
306
307 int
kmdb_module_unloaded(kmdb_wr_unload_t * dur)308 kmdb_module_unloaded(kmdb_wr_unload_t *dur)
309 {
310 mdb_var_t *v;
311
312 if ((v = mdb_nv_lookup(&mdb.m_dmodctl, dur->dur_modname)) == NULL) {
313 mdb_warn("unload for unrequested module %s\n",
314 dur->dur_modname);
315 return (0);
316 }
317
318 if (dur->dur_errno != 0) {
319 mdb_warn("dmod %s failed to unload", dur->dur_modname);
320 return (0);
321 }
322
323 kmc_free(MDB_NV_COOKIE(v));
324 mdb_nv_remove(&mdb.m_dmodctl, v);
325
326 return (1);
327 }
328
329 void
kmdb_module_unload_ack(kmdb_wr_unload_t * dur)330 kmdb_module_unload_ack(kmdb_wr_unload_t *dur)
331 {
332 if (dur->dur_modname != NULL)
333 strfree(dur->dur_modname);
334 mdb_free(dur, sizeof (kmdb_wr_unload_t));
335 }
336
337 /*
338 * Called by the kmdb_kvm target upon debugger reentry, this routine checks
339 * to see if the loaded dmods have changed. Of particular interest is the
340 * exportation of dmod symbol tables, which will happen during the boot
341 * process for dmods that were loaded prior to kernel startup. If this
342 * has occurred, we'll need to reconstruct our view of the symbol tables for
343 * the affected dmods, since the old symbol tables lived in bootmem
344 * and have been moved during the kobj_export_module().
345 *
346 * Also, any ctf_file_t we might have opened is now invalid, since it
347 * has internal pointers to the old data as well.
348 */
349 void
kmdb_module_sync(void)350 kmdb_module_sync(void)
351 {
352 mdb_var_t *v;
353
354 mdb_nv_rewind(&mdb.m_dmodctl);
355 while ((v = mdb_nv_advance(&mdb.m_dmodctl)) != NULL) {
356 kmdb_modctl_t *kmc = MDB_NV_COOKIE(v);
357 struct module *mp;
358
359 if (kmc->kmc_state != KMDB_MC_STATE_LOADED)
360 continue;
361
362 mp = kmc->kmc_modctl->mod_mp;
363
364 if ((mp->flags & (KOBJ_PRIM | KOBJ_EXPORTED)) &&
365 !kmc->kmc_exported) {
366 /*
367 * The exporting process moves the symtab from boot
368 * scratch memory to vmem.
369 */
370 if (kmc->kmc_symtab != NULL)
371 mdb_gelf_symtab_destroy(kmc->kmc_symtab);
372
373 kmc->kmc_symtab = mdb_gelf_symtab_create_raw(
374 &kmc->kmc_ehdr, mp->symhdr, mp->symtbl, mp->strhdr,
375 mp->strings, MDB_TGT_SYMTAB);
376
377 if (kmc->kmc_mod->mod_ctfp != NULL) {
378 ctf_close(kmc->kmc_mod->mod_ctfp);
379 kmc->kmc_mod->mod_ctfp =
380 mdb_ctf_open(kmc->kmc_modname, NULL);
381 }
382 kmc->kmc_exported = TRUE;
383 }
384 }
385 }
386