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1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
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A
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
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7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21/*
6d2010ae 22 * Copyright 2009 Sun Microsystems, Inc. All rights reserved.
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23 * Use is subject to license terms.
24 */
25
b0d623f7 26/* #pragma ident "@(#)fbt.c 1.18 07/01/10 SMI" */
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27
28#ifdef KERNEL
29#ifndef _KERNEL
30#define _KERNEL /* Solaris vs. Darwin */
31#endif
32#endif
33
34#include <mach-o/loader.h>
b0d623f7 35#include <libkern/kernel_mach_header.h>
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36
37#include <sys/param.h>
38#include <sys/systm.h>
39#include <sys/errno.h>
40#include <sys/stat.h>
41#include <sys/ioctl.h>
42#include <sys/conf.h>
43#include <sys/fcntl.h>
44#include <miscfs/devfs/devfs.h>
45#include <pexpert/pexpert.h>
46
47#include <sys/dtrace.h>
48#include <sys/dtrace_impl.h>
49#include <sys/fbt.h>
50
51#include <sys/dtrace_glue.h>
52
53/* #include <machine/trap.h> */
54struct savearea_t; /* Used anonymously */
2d21ac55 55
39236c6e 56typedef kern_return_t (*perfCallback)(int, struct savearea_t *, uintptr_t *, __unused int);
2d21ac55 57extern perfCallback tempDTraceTrapHook;
39236c6e 58extern kern_return_t fbt_perfCallback(int, struct savearea_t *, uintptr_t *, __unused int);
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59
60#define FBT_ADDR2NDX(addr) ((((uintptr_t)(addr)) >> 4) & fbt_probetab_mask)
61#define FBT_PROBETAB_SIZE 0x8000 /* 32k entries -- 128K total */
62
63static dev_info_t *fbt_devi;
64static int fbt_probetab_size;
65dtrace_provider_id_t fbt_id;
66fbt_probe_t **fbt_probetab;
67int fbt_probetab_mask;
68static int fbt_verbose = 0;
69
70void fbt_init( void );
71
72/*ARGSUSED*/
73static void
74fbt_destroy(void *arg, dtrace_id_t id, void *parg)
75{
76#pragma unused(arg,id)
77 fbt_probe_t *fbt = parg, *next, *hash, *last;
78 int ndx;
79
80 do {
81 /*
82 * Now we need to remove this probe from the fbt_probetab.
83 */
84 ndx = FBT_ADDR2NDX(fbt->fbtp_patchpoint);
85 last = NULL;
86 hash = fbt_probetab[ndx];
87
88 while (hash != fbt) {
89 ASSERT(hash != NULL);
90 last = hash;
91 hash = hash->fbtp_hashnext;
92 }
93
94 if (last != NULL) {
95 last->fbtp_hashnext = fbt->fbtp_hashnext;
96 } else {
97 fbt_probetab[ndx] = fbt->fbtp_hashnext;
98 }
99
100 next = fbt->fbtp_next;
101 kmem_free(fbt, sizeof (fbt_probe_t));
102
103 fbt = next;
104 } while (fbt != NULL);
105}
106
107/*ARGSUSED*/
6d2010ae 108int
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109fbt_enable(void *arg, dtrace_id_t id, void *parg)
110{
111#pragma unused(arg,id)
112 fbt_probe_t *fbt = parg;
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113 struct modctl *ctl = NULL;
114
115 for (; fbt != NULL; fbt = fbt->fbtp_next) {
2d21ac55 116
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117 ctl = fbt->fbtp_ctl;
118
119 if (!ctl->mod_loaded) {
2d21ac55 120 if (fbt_verbose) {
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121 cmn_err(CE_NOTE, "fbt is failing for probe %s "
122 "(module %s unloaded)",
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123 fbt->fbtp_name, ctl->mod_modname);
124 }
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125
126 continue;
2d21ac55 127 }
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128
129 /*
130 * Now check that our modctl has the expected load count. If it
131 * doesn't, this module must have been unloaded and reloaded -- and
132 * we're not going to touch it.
133 */
134 if (ctl->mod_loadcnt != fbt->fbtp_loadcnt) {
135 if (fbt_verbose) {
136 cmn_err(CE_NOTE, "fbt is failing for probe %s "
137 "(module %s reloaded)",
138 fbt->fbtp_name, ctl->mod_modname);
139 }
140
141 continue;
142 }
143
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144 dtrace_casptr(&tempDTraceTrapHook, NULL, fbt_perfCallback);
145 if (tempDTraceTrapHook != (perfCallback)fbt_perfCallback) {
146 if (fbt_verbose) {
147 cmn_err(CE_NOTE, "fbt_enable is failing for probe %s "
148 "in module %s: tempDTraceTrapHook already occupied.",
149 fbt->fbtp_name, ctl->mod_modname);
150 }
6d2010ae 151 continue;
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152 }
153
6d2010ae 154 if (fbt->fbtp_currentval != fbt->fbtp_patchval) {
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155 (void)ml_nofault_copy( (vm_offset_t)&fbt->fbtp_patchval, (vm_offset_t)fbt->fbtp_patchpoint,
156 sizeof(fbt->fbtp_patchval));
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157 fbt->fbtp_currentval = fbt->fbtp_patchval;
158 ctl->mod_nenabled++;
159 }
160
161 }
162
163 dtrace_membar_consumer();
164
165 return (0);
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166}
167
168/*ARGSUSED*/
169static void
170fbt_disable(void *arg, dtrace_id_t id, void *parg)
171{
172#pragma unused(arg,id)
173 fbt_probe_t *fbt = parg;
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174 struct modctl *ctl = NULL;
175
176 for (; fbt != NULL; fbt = fbt->fbtp_next) {
177 ctl = fbt->fbtp_ctl;
178
179 if (!ctl->mod_loaded || (ctl->mod_loadcnt != fbt->fbtp_loadcnt))
180 continue;
2d21ac55 181
6d2010ae 182 if (fbt->fbtp_currentval != fbt->fbtp_savedval) {
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183 (void)ml_nofault_copy( (vm_offset_t)&fbt->fbtp_savedval, (vm_offset_t)fbt->fbtp_patchpoint,
184 sizeof(fbt->fbtp_savedval));
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185 fbt->fbtp_currentval = fbt->fbtp_savedval;
186 ASSERT(ctl->mod_nenabled > 0);
187 ctl->mod_nenabled--;
188 }
189 }
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190 dtrace_membar_consumer();
191}
192
193/*ARGSUSED*/
194static void
195fbt_suspend(void *arg, dtrace_id_t id, void *parg)
196{
197#pragma unused(arg,id)
198 fbt_probe_t *fbt = parg;
6d2010ae 199 struct modctl *ctl = NULL;
2d21ac55 200
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201 for (; fbt != NULL; fbt = fbt->fbtp_next) {
202 ctl = fbt->fbtp_ctl;
203
204 ASSERT(ctl->mod_nenabled > 0);
205 if (!ctl->mod_loaded || (ctl->mod_loadcnt != fbt->fbtp_loadcnt))
206 continue;
207
208 (void)ml_nofault_copy( (vm_offset_t)&fbt->fbtp_savedval, (vm_offset_t)fbt->fbtp_patchpoint,
2d21ac55 209 sizeof(fbt->fbtp_savedval));
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210
211
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212 fbt->fbtp_currentval = fbt->fbtp_savedval;
213 }
214
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215 dtrace_membar_consumer();
216}
217
218/*ARGSUSED*/
219static void
220fbt_resume(void *arg, dtrace_id_t id, void *parg)
221{
222#pragma unused(arg,id)
223 fbt_probe_t *fbt = parg;
6d2010ae 224 struct modctl *ctl = NULL;
2d21ac55 225
6d2010ae
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226 for (; fbt != NULL; fbt = fbt->fbtp_next) {
227 ctl = fbt->fbtp_ctl;
228
229 ASSERT(ctl->mod_nenabled > 0);
230 if (!ctl->mod_loaded || (ctl->mod_loadcnt != fbt->fbtp_loadcnt))
231 continue;
2d21ac55 232
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233 dtrace_casptr(&tempDTraceTrapHook, NULL, fbt_perfCallback);
234 if (tempDTraceTrapHook != (perfCallback)fbt_perfCallback) {
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235 if (fbt_verbose) {
236 cmn_err(CE_NOTE, "fbt_resume is failing for probe %s "
237 "in module %s: tempDTraceTrapHook already occupied.",
238 fbt->fbtp_name, ctl->mod_modname);
239 }
240 return;
6d2010ae 241 }
2d21ac55 242
6d2010ae 243 (void)ml_nofault_copy( (vm_offset_t)&fbt->fbtp_patchval, (vm_offset_t)fbt->fbtp_patchpoint,
2d21ac55 244 sizeof(fbt->fbtp_patchval));
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245
246
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247 fbt->fbtp_currentval = fbt->fbtp_patchval;
248 }
249
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250 dtrace_membar_consumer();
251}
252
253#if !defined(__APPLE__)
254/*ARGSUSED*/
255static void
256fbt_getargdesc(void *arg, dtrace_id_t id, void *parg, dtrace_argdesc_t *desc)
257{
258 fbt_probe_t *fbt = parg;
259 struct modctl *ctl = fbt->fbtp_ctl;
260 struct module *mp = ctl->mod_mp;
261 ctf_file_t *fp = NULL, *pfp;
262 ctf_funcinfo_t f;
263 int error;
264 ctf_id_t argv[32], type;
265 int argc = sizeof (argv) / sizeof (ctf_id_t);
266 const char *parent;
267
268 if (!ctl->mod_loaded || (ctl->mod_loadcnt != fbt->fbtp_loadcnt))
269 goto err;
270
271 if (fbt->fbtp_roffset != 0 && desc->dtargd_ndx == 0) {
272 (void) strlcpy(desc->dtargd_native, "int",
273 sizeof(desc->dtargd_native));
274 return;
275 }
276
277 if ((fp = ctf_modopen(mp, &error)) == NULL) {
278 /*
279 * We have no CTF information for this module -- and therefore
280 * no args[] information.
281 */
282 goto err;
283 }
284
285 /*
286 * If we have a parent container, we must manually import it.
287 */
288 if ((parent = ctf_parent_name(fp)) != NULL) {
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289 struct modctl *mp = &modules;
290 struct modctl *mod = NULL;
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291
292 /*
293 * We must iterate over all modules to find the module that
294 * is our parent.
295 */
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296 do {
297 if (strcmp(mp->mod_modname, parent) == 0) {
298 mod = mp;
2d21ac55 299 break;
b0d623f7
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300 }
301 } while ((mp = mp->mod_next) != &modules);
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302
303 if (mod == NULL)
304 goto err;
305
b0d623f7 306 if ((pfp = ctf_modopen(mod->mod_mp, &error)) == NULL) {
2d21ac55 307 goto err;
b0d623f7 308 }
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309
310 if (ctf_import(fp, pfp) != 0) {
311 ctf_close(pfp);
312 goto err;
313 }
314
315 ctf_close(pfp);
316 }
317
318 if (ctf_func_info(fp, fbt->fbtp_symndx, &f) == CTF_ERR)
319 goto err;
320
321 if (fbt->fbtp_roffset != 0) {
322 if (desc->dtargd_ndx > 1)
323 goto err;
324
325 ASSERT(desc->dtargd_ndx == 1);
326 type = f.ctc_return;
327 } else {
328 if (desc->dtargd_ndx + 1 > f.ctc_argc)
329 goto err;
330
331 if (ctf_func_args(fp, fbt->fbtp_symndx, argc, argv) == CTF_ERR)
332 goto err;
333
334 type = argv[desc->dtargd_ndx];
335 }
336
337 if (ctf_type_name(fp, type, desc->dtargd_native,
338 DTRACE_ARGTYPELEN) != NULL) {
339 ctf_close(fp);
340 return;
341 }
342err:
343 if (fp != NULL)
344 ctf_close(fp);
345
346 desc->dtargd_ndx = DTRACE_ARGNONE;
347}
348#endif /* __APPLE__ */
349
350static dtrace_pattr_t fbt_attr = {
351{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_ISA },
352{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
353{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
354{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_ISA },
355{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA },
356};
357
358static dtrace_pops_t fbt_pops = {
359 NULL,
360 fbt_provide_module,
361 fbt_enable,
362 fbt_disable,
363 fbt_suspend,
364 fbt_resume,
365#if !defined(__APPLE__)
366 fbt_getargdesc,
367#else
b0d623f7 368 NULL, /* FIXME: where to look for xnu? */
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369#endif /* __APPLE__ */
370 NULL,
371 NULL,
372 fbt_destroy
373};
374
375static void
376fbt_cleanup(dev_info_t *devi)
377{
378 dtrace_invop_remove(fbt_invop);
379 ddi_remove_minor_node(devi, NULL);
380 kmem_free(fbt_probetab, fbt_probetab_size * sizeof (fbt_probe_t *));
381 fbt_probetab = NULL;
382 fbt_probetab_mask = 0;
383}
384
385static int
386fbt_attach(dev_info_t *devi, ddi_attach_cmd_t cmd)
387{
388 switch (cmd) {
389 case DDI_ATTACH:
390 break;
391 case DDI_RESUME:
392 return (DDI_SUCCESS);
393 default:
394 return (DDI_FAILURE);
395 }
396
397 if (fbt_probetab_size == 0)
398 fbt_probetab_size = FBT_PROBETAB_SIZE;
399
400 fbt_probetab_mask = fbt_probetab_size - 1;
401 fbt_probetab =
402 kmem_zalloc(fbt_probetab_size * sizeof (fbt_probe_t *), KM_SLEEP);
403
404 dtrace_invop_add(fbt_invop);
405
b0d623f7 406#if !defined(__APPLE__)
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407 if (ddi_create_minor_node(devi, "fbt", S_IFCHR, 0,
408 DDI_PSEUDO, NULL) == DDI_FAILURE ||
409 dtrace_register("fbt", &fbt_attr, DTRACE_PRIV_KERNEL, NULL,
410 &fbt_pops, NULL, &fbt_id) != 0) {
411 fbt_cleanup(devi);
412 return (DDI_FAILURE);
413 }
b0d623f7
A
414#else
415 if (ddi_create_minor_node(devi, "fbt", S_IFCHR, 0,
416 DDI_PSEUDO, 0) == DDI_FAILURE ||
417 dtrace_register("fbt", &fbt_attr, DTRACE_PRIV_KERNEL, NULL,
418 &fbt_pops, NULL, &fbt_id) != 0) {
419 fbt_cleanup(devi);
420 return (DDI_FAILURE);
421 }
422#endif /* __APPLE__ */
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423
424 ddi_report_dev(devi);
425 fbt_devi = devi;
426
427 return (DDI_SUCCESS);
428}
429
430static d_open_t _fbt_open;
431
432static int
433_fbt_open(dev_t dev, int flags, int devtype, struct proc *p)
434{
435#pragma unused(dev,flags,devtype,p)
436 return 0;
437}
438
439#define FBT_MAJOR -24 /* let the kernel pick the device number */
440
441/*
442 * A struct describing which functions will get invoked for certain
443 * actions.
444 */
445static struct cdevsw fbt_cdevsw =
446{
447 _fbt_open, /* open */
448 eno_opcl, /* close */
449 eno_rdwrt, /* read */
450 eno_rdwrt, /* write */
451 eno_ioctl, /* ioctl */
452 (stop_fcn_t *)nulldev, /* stop */
453 (reset_fcn_t *)nulldev, /* reset */
454 NULL, /* tty's */
455 eno_select, /* select */
456 eno_mmap, /* mmap */
457 eno_strat, /* strategy */
458 eno_getc, /* getc */
459 eno_putc, /* putc */
460 0 /* type */
461};
462
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463int gIgnoreFBTBlacklist = 0;
464static int gFBTInited = 0;
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465#undef kmem_alloc /* from its binding to dt_kmem_alloc glue */
466#undef kmem_free /* from its binding to dt_kmem_free glue */
467#include <vm/vm_kern.h>
468
469void
470fbt_init( void )
471{
6d2010ae 472 if (0 == gFBTInited)
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473 {
474 int majdevno = cdevsw_add(FBT_MAJOR, &fbt_cdevsw);
2d21ac55
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475
476 if (majdevno < 0) {
477 printf("fbt_init: failed to allocate a major number!\n");
478 return;
479 }
6d2010ae
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480
481 PE_parse_boot_argn("IgnoreFBTBlacklist", &gIgnoreFBTBlacklist, sizeof (gIgnoreFBTBlacklist));
2d21ac55 482
b0d623f7 483 fbt_attach( (dev_info_t *)(uintptr_t)majdevno, DDI_ATTACH );
6d2010ae
A
484
485 gFBTInited = 1; /* Ensure this initialization occurs just one time. */
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486 }
487 else
6d2010ae 488 panic("fbt_init: called twice!\n");
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489}
490#undef FBT_MAJOR