xref: /freebsd/cddl/contrib/opensolaris/lib/libdtrace/common/dt_dof.c (revision 9a14aa017b21c292740c00ee098195cd46642730)
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 (the "License").
6  * You may not use this file except in compliance with the License.
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 
22 /*
23  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
24  */
25 
26 #include <sys/types.h>
27 #if defined(sun)
28 #include <sys/sysmacros.h>
29 #endif
30 
31 #include <strings.h>
32 #if defined(sun)
33 #include <alloca.h>
34 #endif
35 #include <assert.h>
36 #include <stdlib.h>
37 #include <errno.h>
38 #include <limits.h>
39 
40 #include <dt_impl.h>
41 #include <dt_strtab.h>
42 #include <dt_program.h>
43 #include <dt_provider.h>
44 #include <dt_xlator.h>
45 #include <dt_dof.h>
46 
47 void
48 dt_dof_init(dtrace_hdl_t *dtp)
49 {
50 	dt_dof_t *ddo = &dtp->dt_dof;
51 
52 	ddo->ddo_hdl = dtp;
53 	ddo->ddo_nsecs = 0;
54 	ddo->ddo_strsec = DOF_SECIDX_NONE;
55 	ddo->ddo_xlimport = NULL;
56 	ddo->ddo_xlexport = NULL;
57 
58 	dt_buf_create(dtp, &ddo->ddo_secs, "section headers", 0);
59 	dt_buf_create(dtp, &ddo->ddo_strs, "string table", 0);
60 	dt_buf_create(dtp, &ddo->ddo_ldata, "loadable data", 0);
61 	dt_buf_create(dtp, &ddo->ddo_udata, "unloadable data", 0);
62 
63 	dt_buf_create(dtp, &ddo->ddo_probes, "probe data", 0);
64 	dt_buf_create(dtp, &ddo->ddo_args, "probe args", 0);
65 	dt_buf_create(dtp, &ddo->ddo_offs, "probe offs", 0);
66 	dt_buf_create(dtp, &ddo->ddo_enoffs, "probe is-enabled offs", 0);
67 	dt_buf_create(dtp, &ddo->ddo_rels, "probe rels", 0);
68 
69 	dt_buf_create(dtp, &ddo->ddo_xlms, "xlate members", 0);
70 }
71 
72 void
73 dt_dof_fini(dtrace_hdl_t *dtp)
74 {
75 	dt_dof_t *ddo = &dtp->dt_dof;
76 
77 	dt_free(dtp, ddo->ddo_xlimport);
78 	dt_free(dtp, ddo->ddo_xlexport);
79 
80 	dt_buf_destroy(dtp, &ddo->ddo_secs);
81 	dt_buf_destroy(dtp, &ddo->ddo_strs);
82 	dt_buf_destroy(dtp, &ddo->ddo_ldata);
83 	dt_buf_destroy(dtp, &ddo->ddo_udata);
84 
85 	dt_buf_destroy(dtp, &ddo->ddo_probes);
86 	dt_buf_destroy(dtp, &ddo->ddo_args);
87 	dt_buf_destroy(dtp, &ddo->ddo_offs);
88 	dt_buf_destroy(dtp, &ddo->ddo_enoffs);
89 	dt_buf_destroy(dtp, &ddo->ddo_rels);
90 
91 	dt_buf_destroy(dtp, &ddo->ddo_xlms);
92 }
93 
94 static int
95 dt_dof_reset(dtrace_hdl_t *dtp, dtrace_prog_t *pgp)
96 {
97 	dt_dof_t *ddo = &dtp->dt_dof;
98 	uint_t i, nx = dtp->dt_xlatorid;
99 
100 	assert(ddo->ddo_hdl == dtp);
101 	ddo->ddo_pgp = pgp;
102 
103 	ddo->ddo_nsecs = 0;
104 	ddo->ddo_strsec = DOF_SECIDX_NONE;
105 
106 	dt_free(dtp, ddo->ddo_xlimport);
107 	dt_free(dtp, ddo->ddo_xlexport);
108 
109 	ddo->ddo_xlimport = dt_alloc(dtp, sizeof (dof_secidx_t) * nx);
110 	ddo->ddo_xlexport = dt_alloc(dtp, sizeof (dof_secidx_t) * nx);
111 
112 	if (nx != 0 && (ddo->ddo_xlimport == NULL || ddo->ddo_xlexport == NULL))
113 		return (-1); /* errno is set for us */
114 
115 	for (i = 0; i < nx; i++) {
116 		ddo->ddo_xlimport[i] = DOF_SECIDX_NONE;
117 		ddo->ddo_xlexport[i] = DOF_SECIDX_NONE;
118 	}
119 
120 	dt_buf_reset(dtp, &ddo->ddo_secs);
121 	dt_buf_reset(dtp, &ddo->ddo_strs);
122 	dt_buf_reset(dtp, &ddo->ddo_ldata);
123 	dt_buf_reset(dtp, &ddo->ddo_udata);
124 
125 	dt_buf_reset(dtp, &ddo->ddo_probes);
126 	dt_buf_reset(dtp, &ddo->ddo_args);
127 	dt_buf_reset(dtp, &ddo->ddo_offs);
128 	dt_buf_reset(dtp, &ddo->ddo_enoffs);
129 	dt_buf_reset(dtp, &ddo->ddo_rels);
130 
131 	dt_buf_reset(dtp, &ddo->ddo_xlms);
132 	return (0);
133 }
134 
135 /*
136  * Add a loadable DOF section to the file using the specified data buffer and
137  * the specified DOF section attributes.  DOF_SECF_LOAD must be set in flags.
138  * If 'data' is NULL, the caller is responsible for manipulating the ldata buf.
139  */
140 static dof_secidx_t
141 dof_add_lsect(dt_dof_t *ddo, const void *data, uint32_t type,
142     uint32_t align, uint32_t flags, uint32_t entsize, uint64_t size)
143 {
144 	dtrace_hdl_t *dtp = ddo->ddo_hdl;
145 	dof_sec_t s;
146 
147 	s.dofs_type = type;
148 	s.dofs_align = align;
149 	s.dofs_flags = flags | DOF_SECF_LOAD;
150 	s.dofs_entsize = entsize;
151 	s.dofs_offset = dt_buf_offset(&ddo->ddo_ldata, align);
152 	s.dofs_size = size;
153 
154 	dt_buf_write(dtp, &ddo->ddo_secs, &s, sizeof (s), sizeof (uint64_t));
155 
156 	if (data != NULL)
157 		dt_buf_write(dtp, &ddo->ddo_ldata, data, size, align);
158 
159 	return (ddo->ddo_nsecs++);
160 }
161 
162 /*
163  * Add an unloadable DOF section to the file using the specified data buffer
164  * and DOF section attributes.  DOF_SECF_LOAD must *not* be set in flags.
165  * If 'data' is NULL, the caller is responsible for manipulating the udata buf.
166  */
167 static dof_secidx_t
168 dof_add_usect(dt_dof_t *ddo, const void *data, uint32_t type,
169     uint32_t align, uint32_t flags, uint32_t entsize, uint64_t size)
170 {
171 	dtrace_hdl_t *dtp = ddo->ddo_hdl;
172 	dof_sec_t s;
173 
174 	s.dofs_type = type;
175 	s.dofs_align = align;
176 	s.dofs_flags = flags & ~DOF_SECF_LOAD;
177 	s.dofs_entsize = entsize;
178 	s.dofs_offset = dt_buf_offset(&ddo->ddo_udata, align);
179 	s.dofs_size = size;
180 
181 	dt_buf_write(dtp, &ddo->ddo_secs, &s, sizeof (s), sizeof (uint64_t));
182 
183 	if (data != NULL)
184 		dt_buf_write(dtp, &ddo->ddo_udata, data, size, align);
185 
186 	return (ddo->ddo_nsecs++);
187 }
188 
189 /*
190  * Add a string to the global string table associated with the DOF.  The offset
191  * of the string is returned as an index into the string table.
192  */
193 static dof_stridx_t
194 dof_add_string(dt_dof_t *ddo, const char *s)
195 {
196 	dt_buf_t *bp = &ddo->ddo_strs;
197 	dof_stridx_t i = dt_buf_len(bp);
198 
199 	if (i != 0 && (s == NULL || *s == '\0'))
200 		return (0); /* string table has \0 at offset 0 */
201 
202 	dt_buf_write(ddo->ddo_hdl, bp, s, strlen(s) + 1, sizeof (char));
203 	return (i);
204 }
205 
206 static dof_attr_t
207 dof_attr(const dtrace_attribute_t *ap)
208 {
209 	return (DOF_ATTR(ap->dtat_name, ap->dtat_data, ap->dtat_class));
210 }
211 
212 static dof_secidx_t
213 dof_add_difo(dt_dof_t *ddo, const dtrace_difo_t *dp)
214 {
215 	dof_secidx_t dsecs[5]; /* enough for all possible DIFO sections */
216 	uint_t nsecs = 0;
217 
218 	dof_difohdr_t *dofd;
219 	dof_relohdr_t dofr;
220 	dof_secidx_t relsec;
221 
222 	dof_secidx_t strsec = DOF_SECIDX_NONE;
223 	dof_secidx_t intsec = DOF_SECIDX_NONE;
224 	dof_secidx_t hdrsec = DOF_SECIDX_NONE;
225 
226 	if (dp->dtdo_buf != NULL) {
227 		dsecs[nsecs++] = dof_add_lsect(ddo, dp->dtdo_buf,
228 		    DOF_SECT_DIF, sizeof (dif_instr_t), 0,
229 		    sizeof (dif_instr_t), sizeof (dif_instr_t) * dp->dtdo_len);
230 	}
231 
232 	if (dp->dtdo_inttab != NULL) {
233 		dsecs[nsecs++] = intsec = dof_add_lsect(ddo, dp->dtdo_inttab,
234 		    DOF_SECT_INTTAB, sizeof (uint64_t), 0,
235 		    sizeof (uint64_t), sizeof (uint64_t) * dp->dtdo_intlen);
236 	}
237 
238 	if (dp->dtdo_strtab != NULL) {
239 		dsecs[nsecs++] = strsec = dof_add_lsect(ddo, dp->dtdo_strtab,
240 		    DOF_SECT_STRTAB, sizeof (char), 0, 0, dp->dtdo_strlen);
241 	}
242 
243 	if (dp->dtdo_vartab != NULL) {
244 		dsecs[nsecs++] = dof_add_lsect(ddo, dp->dtdo_vartab,
245 		    DOF_SECT_VARTAB, sizeof (uint_t), 0, sizeof (dtrace_difv_t),
246 		    sizeof (dtrace_difv_t) * dp->dtdo_varlen);
247 	}
248 
249 	if (dp->dtdo_xlmtab != NULL) {
250 		dof_xlref_t *xlt, *xlp;
251 		dt_node_t **pnp;
252 
253 		xlt = alloca(sizeof (dof_xlref_t) * dp->dtdo_xlmlen);
254 		pnp = dp->dtdo_xlmtab;
255 
256 		/*
257 		 * dtdo_xlmtab contains pointers to the translator members.
258 		 * The translator itself is in sect ddo_xlimport[dxp->dx_id].
259 		 * The XLMEMBERS entries are in order by their dn_membid, so
260 		 * the member section offset is the population count of bits
261 		 * in ddo_pgp->dp_xlrefs[] up to and not including dn_membid.
262 		 */
263 		for (xlp = xlt; xlp < xlt + dp->dtdo_xlmlen; xlp++) {
264 			dt_node_t *dnp = *pnp++;
265 			dt_xlator_t *dxp = dnp->dn_membexpr->dn_xlator;
266 
267 			xlp->dofxr_xlator = ddo->ddo_xlimport[dxp->dx_id];
268 			xlp->dofxr_member = dt_popcb(
269 			    ddo->ddo_pgp->dp_xrefs[dxp->dx_id], dnp->dn_membid);
270 			xlp->dofxr_argn = (uint32_t)dxp->dx_arg;
271 		}
272 
273 		dsecs[nsecs++] = dof_add_lsect(ddo, xlt, DOF_SECT_XLTAB,
274 		    sizeof (dof_secidx_t), 0, sizeof (dof_xlref_t),
275 		    sizeof (dof_xlref_t) * dp->dtdo_xlmlen);
276 	}
277 
278 	/*
279 	 * Copy the return type and the array of section indices that form the
280 	 * DIFO into a single dof_difohdr_t and then add DOF_SECT_DIFOHDR.
281 	 */
282 	assert(nsecs <= sizeof (dsecs) / sizeof (dsecs[0]));
283 	dofd = alloca(sizeof (dtrace_diftype_t) + sizeof (dsecs));
284 	bcopy(&dp->dtdo_rtype, &dofd->dofd_rtype, sizeof (dtrace_diftype_t));
285 	bcopy(dsecs, &dofd->dofd_links, sizeof (dof_secidx_t) * nsecs);
286 
287 	hdrsec = dof_add_lsect(ddo, dofd, DOF_SECT_DIFOHDR,
288 	    sizeof (dof_secidx_t), 0, 0,
289 	    sizeof (dtrace_diftype_t) + sizeof (dof_secidx_t) * nsecs);
290 
291 	/*
292 	 * Add any other sections related to dtrace_difo_t.  These are not
293 	 * referenced in dof_difohdr_t because they are not used by emulation.
294 	 */
295 	if (dp->dtdo_kreltab != NULL) {
296 		relsec = dof_add_lsect(ddo, dp->dtdo_kreltab, DOF_SECT_RELTAB,
297 		    sizeof (uint64_t), 0, sizeof (dof_relodesc_t),
298 		    sizeof (dof_relodesc_t) * dp->dtdo_krelen);
299 
300 		/*
301 		 * This code assumes the target of all relocations is the
302 		 * integer table 'intsec' (DOF_SECT_INTTAB).  If other sections
303 		 * need relocation in the future this will need to change.
304 		 */
305 		dofr.dofr_strtab = strsec;
306 		dofr.dofr_relsec = relsec;
307 		dofr.dofr_tgtsec = intsec;
308 
309 		(void) dof_add_lsect(ddo, &dofr, DOF_SECT_KRELHDR,
310 		    sizeof (dof_secidx_t), 0, 0, sizeof (dof_relohdr_t));
311 	}
312 
313 	if (dp->dtdo_ureltab != NULL) {
314 		relsec = dof_add_lsect(ddo, dp->dtdo_ureltab, DOF_SECT_RELTAB,
315 		    sizeof (uint64_t), 0, sizeof (dof_relodesc_t),
316 		    sizeof (dof_relodesc_t) * dp->dtdo_urelen);
317 
318 		/*
319 		 * This code assumes the target of all relocations is the
320 		 * integer table 'intsec' (DOF_SECT_INTTAB).  If other sections
321 		 * need relocation in the future this will need to change.
322 		 */
323 		dofr.dofr_strtab = strsec;
324 		dofr.dofr_relsec = relsec;
325 		dofr.dofr_tgtsec = intsec;
326 
327 		(void) dof_add_lsect(ddo, &dofr, DOF_SECT_URELHDR,
328 		    sizeof (dof_secidx_t), 0, 0, sizeof (dof_relohdr_t));
329 	}
330 
331 	return (hdrsec);
332 }
333 
334 static void
335 dof_add_translator(dt_dof_t *ddo, const dt_xlator_t *dxp, uint_t type)
336 {
337 	dtrace_hdl_t *dtp = ddo->ddo_hdl;
338 	dof_xlmember_t dofxm;
339 	dof_xlator_t dofxl;
340 	dof_secidx_t *xst;
341 
342 	char buf[DT_TYPE_NAMELEN];
343 	dt_node_t *dnp;
344 	uint_t i = 0;
345 
346 	assert(type == DOF_SECT_XLIMPORT || type == DOF_SECT_XLEXPORT);
347 	xst = type == DOF_SECT_XLIMPORT ? ddo->ddo_xlimport : ddo->ddo_xlexport;
348 
349 	if (xst[dxp->dx_id] != DOF_SECIDX_NONE)
350 		return; /* translator has already been emitted */
351 
352 	dt_buf_reset(dtp, &ddo->ddo_xlms);
353 
354 	/*
355 	 * Generate an array of dof_xlmember_t's into ddo_xlms.  If we are
356 	 * importing the translator, add only those members referenced by the
357 	 * program and set the dofxm_difo reference of each member to NONE.  If
358 	 * we're exporting the translator, add all members and a DIFO for each.
359 	 */
360 	for (dnp = dxp->dx_members; dnp != NULL; dnp = dnp->dn_list, i++) {
361 		if (type == DOF_SECT_XLIMPORT) {
362 			if (!BT_TEST(ddo->ddo_pgp->dp_xrefs[dxp->dx_id], i))
363 				continue; /* member is not referenced */
364 			dofxm.dofxm_difo = DOF_SECIDX_NONE;
365 		} else {
366 			dofxm.dofxm_difo = dof_add_difo(ddo,
367 			    dxp->dx_membdif[dnp->dn_membid]);
368 		}
369 
370 		dofxm.dofxm_name = dof_add_string(ddo, dnp->dn_membname);
371 		dt_node_diftype(dtp, dnp, &dofxm.dofxm_type);
372 
373 		dt_buf_write(dtp, &ddo->ddo_xlms,
374 		    &dofxm, sizeof (dofxm), sizeof (uint32_t));
375 	}
376 
377 	dofxl.dofxl_members = dof_add_lsect(ddo, NULL, DOF_SECT_XLMEMBERS,
378 	    sizeof (uint32_t), 0, sizeof (dofxm), dt_buf_len(&ddo->ddo_xlms));
379 
380 	dt_buf_concat(dtp, &ddo->ddo_ldata, &ddo->ddo_xlms, sizeof (uint32_t));
381 
382 	dofxl.dofxl_strtab = ddo->ddo_strsec;
383 	dofxl.dofxl_argv = dof_add_string(ddo, ctf_type_name(
384 	    dxp->dx_src_ctfp, dxp->dx_src_type, buf, sizeof (buf)));
385 	dofxl.dofxl_argc = 1;
386 	dofxl.dofxl_type = dof_add_string(ddo, ctf_type_name(
387 	    dxp->dx_dst_ctfp, dxp->dx_dst_type, buf, sizeof (buf)));
388 	dofxl.dofxl_attr = dof_attr(&dxp->dx_souid.di_attr);
389 
390 	xst[dxp->dx_id] = dof_add_lsect(ddo, &dofxl, type,
391 	    sizeof (uint32_t), 0, 0, sizeof (dofxl));
392 }
393 
394 /*ARGSUSED*/
395 static int
396 dof_add_probe(dt_idhash_t *dhp, dt_ident_t *idp, void *data)
397 {
398 	dt_dof_t *ddo = data;
399 	dtrace_hdl_t *dtp = ddo->ddo_hdl;
400 	dt_probe_t *prp = idp->di_data;
401 
402 	dof_probe_t dofpr;
403 	dof_relodesc_t dofr;
404 	dt_probe_instance_t *pip;
405 	dt_node_t *dnp;
406 
407 	char buf[DT_TYPE_NAMELEN];
408 	uint_t i;
409 
410 	dofpr.dofpr_addr = 0;
411 	dofpr.dofpr_name = dof_add_string(ddo, prp->pr_name);
412 	dofpr.dofpr_nargv = dt_buf_len(&ddo->ddo_strs);
413 
414 	for (dnp = prp->pr_nargs; dnp != NULL; dnp = dnp->dn_list) {
415 		(void) dof_add_string(ddo, ctf_type_name(dnp->dn_ctfp,
416 		    dnp->dn_type, buf, sizeof (buf)));
417 	}
418 
419 	dofpr.dofpr_xargv = dt_buf_len(&ddo->ddo_strs);
420 
421 	for (dnp = prp->pr_xargs; dnp != NULL; dnp = dnp->dn_list) {
422 		(void) dof_add_string(ddo, ctf_type_name(dnp->dn_ctfp,
423 		    dnp->dn_type, buf, sizeof (buf)));
424 	}
425 
426 	dofpr.dofpr_argidx = dt_buf_len(&ddo->ddo_args) / sizeof (uint8_t);
427 
428 	for (i = 0; i < prp->pr_xargc; i++) {
429 		dt_buf_write(dtp, &ddo->ddo_args, &prp->pr_mapping[i],
430 		    sizeof (uint8_t), sizeof (uint8_t));
431 	}
432 
433 	dofpr.dofpr_nargc = prp->pr_nargc;
434 	dofpr.dofpr_xargc = prp->pr_xargc;
435 	dofpr.dofpr_pad1 = 0;
436 	dofpr.dofpr_pad2 = 0;
437 
438 	for (pip = prp->pr_inst; pip != NULL; pip = pip->pi_next) {
439 		dt_dprintf("adding probe for %s:%s\n", pip->pi_fname,
440 		    prp->pr_name);
441 
442 		dofpr.dofpr_func = dof_add_string(ddo, pip->pi_fname);
443 
444 		/*
445 		 * There should be one probe offset or is-enabled probe offset
446 		 * or else this probe instance won't have been created. The
447 		 * kernel will reject DOF which has a probe with no offsets.
448 		 */
449 		assert(pip->pi_noffs + pip->pi_nenoffs > 0);
450 
451 		dofpr.dofpr_offidx =
452 		    dt_buf_len(&ddo->ddo_offs) / sizeof (uint32_t);
453 		dofpr.dofpr_noffs = pip->pi_noffs;
454 		dt_buf_write(dtp, &ddo->ddo_offs, pip->pi_offs,
455 		    pip->pi_noffs * sizeof (uint32_t), sizeof (uint32_t));
456 
457 		dofpr.dofpr_enoffidx =
458 		    dt_buf_len(&ddo->ddo_enoffs) / sizeof (uint32_t);
459 		dofpr.dofpr_nenoffs = pip->pi_nenoffs;
460 		dt_buf_write(dtp, &ddo->ddo_enoffs, pip->pi_enoffs,
461 		    pip->pi_nenoffs * sizeof (uint32_t), sizeof (uint32_t));
462 
463 		/*
464 		 * If pi_rname isn't set, the relocation will be against the
465 		 * function name. If it is, the relocation will be against
466 		 * pi_rname. This will be used if the function is scoped
467 		 * locally so an alternate symbol is added for the purpose
468 		 * of this relocation.
469 		 */
470 		if (pip->pi_rname[0] == '\0')
471 			dofr.dofr_name = dofpr.dofpr_func;
472 		else
473 			dofr.dofr_name = dof_add_string(ddo, pip->pi_rname);
474 		dofr.dofr_type = DOF_RELO_SETX;
475 		dofr.dofr_offset = dt_buf_len(&ddo->ddo_probes);
476 		dofr.dofr_data = 0;
477 
478 		dt_buf_write(dtp, &ddo->ddo_rels, &dofr,
479 		    sizeof (dofr), sizeof (uint64_t));
480 
481 		dt_buf_write(dtp, &ddo->ddo_probes, &dofpr,
482 		    sizeof (dofpr), sizeof (uint64_t));
483 	}
484 
485 	return (0);
486 }
487 
488 static void
489 dof_add_provider(dt_dof_t *ddo, const dt_provider_t *pvp)
490 {
491 	dtrace_hdl_t *dtp = ddo->ddo_hdl;
492 	dof_provider_t dofpv;
493 	dof_relohdr_t dofr;
494 	dof_secidx_t *dofs;
495 	ulong_t xr, nxr;
496 	size_t sz;
497 	id_t i;
498 
499 	if (pvp->pv_flags & DT_PROVIDER_IMPL)
500 		return; /* ignore providers that are exported by dtrace(7D) */
501 
502 	nxr = dt_popcb(pvp->pv_xrefs, pvp->pv_xrmax);
503 	dofs = alloca(sizeof (dof_secidx_t) * (nxr + 1));
504 	xr = 1; /* reserve dofs[0] for the provider itself */
505 
506 	/*
507 	 * For each translator referenced by the provider (pv_xrefs), emit an
508 	 * exported translator section for it if one hasn't been created yet.
509 	 */
510 	for (i = 0; i < pvp->pv_xrmax; i++) {
511 		if (BT_TEST(pvp->pv_xrefs, i) &&
512 		    dtp->dt_xlatemode == DT_XL_DYNAMIC) {
513 			dof_add_translator(ddo,
514 			    dt_xlator_lookup_id(dtp, i), DOF_SECT_XLEXPORT);
515 			dofs[xr++] = ddo->ddo_xlexport[i];
516 		}
517 	}
518 
519 	dt_buf_reset(dtp, &ddo->ddo_probes);
520 	dt_buf_reset(dtp, &ddo->ddo_args);
521 	dt_buf_reset(dtp, &ddo->ddo_offs);
522 	dt_buf_reset(dtp, &ddo->ddo_enoffs);
523 	dt_buf_reset(dtp, &ddo->ddo_rels);
524 
525 	(void) dt_idhash_iter(pvp->pv_probes, dof_add_probe, ddo);
526 
527 	dofpv.dofpv_probes = dof_add_lsect(ddo, NULL, DOF_SECT_PROBES,
528 	    sizeof (uint64_t), 0, sizeof (dof_probe_t),
529 	    dt_buf_len(&ddo->ddo_probes));
530 
531 	dt_buf_concat(dtp, &ddo->ddo_ldata,
532 	    &ddo->ddo_probes, sizeof (uint64_t));
533 
534 	dofpv.dofpv_prargs = dof_add_lsect(ddo, NULL, DOF_SECT_PRARGS,
535 	    sizeof (uint8_t), 0, sizeof (uint8_t), dt_buf_len(&ddo->ddo_args));
536 
537 	dt_buf_concat(dtp, &ddo->ddo_ldata, &ddo->ddo_args, sizeof (uint8_t));
538 
539 	dofpv.dofpv_proffs = dof_add_lsect(ddo, NULL, DOF_SECT_PROFFS,
540 	    sizeof (uint_t), 0, sizeof (uint_t), dt_buf_len(&ddo->ddo_offs));
541 
542 	dt_buf_concat(dtp, &ddo->ddo_ldata, &ddo->ddo_offs, sizeof (uint_t));
543 
544 	if ((sz = dt_buf_len(&ddo->ddo_enoffs)) != 0) {
545 		dofpv.dofpv_prenoffs = dof_add_lsect(ddo, NULL,
546 		    DOF_SECT_PRENOFFS, sizeof (uint_t), 0, sizeof (uint_t), sz);
547 	} else {
548 		dofpv.dofpv_prenoffs = DOF_SECT_NONE;
549 	}
550 
551 	dt_buf_concat(dtp, &ddo->ddo_ldata, &ddo->ddo_enoffs, sizeof (uint_t));
552 
553 	dofpv.dofpv_strtab = ddo->ddo_strsec;
554 	dofpv.dofpv_name = dof_add_string(ddo, pvp->pv_desc.dtvd_name);
555 
556 	dofpv.dofpv_provattr = dof_attr(&pvp->pv_desc.dtvd_attr.dtpa_provider);
557 	dofpv.dofpv_modattr = dof_attr(&pvp->pv_desc.dtvd_attr.dtpa_mod);
558 	dofpv.dofpv_funcattr = dof_attr(&pvp->pv_desc.dtvd_attr.dtpa_func);
559 	dofpv.dofpv_nameattr = dof_attr(&pvp->pv_desc.dtvd_attr.dtpa_name);
560 	dofpv.dofpv_argsattr = dof_attr(&pvp->pv_desc.dtvd_attr.dtpa_args);
561 
562 	dofs[0] = dof_add_lsect(ddo, &dofpv, DOF_SECT_PROVIDER,
563 	    sizeof (dof_secidx_t), 0, 0, sizeof (dof_provider_t));
564 
565 	dofr.dofr_strtab = dofpv.dofpv_strtab;
566 	dofr.dofr_tgtsec = dofpv.dofpv_probes;
567 	dofr.dofr_relsec = dof_add_lsect(ddo, NULL, DOF_SECT_RELTAB,
568 	    sizeof (uint64_t), 0, sizeof (dof_relodesc_t),
569 	    dt_buf_len(&ddo->ddo_rels));
570 
571 	dt_buf_concat(dtp, &ddo->ddo_ldata, &ddo->ddo_rels, sizeof (uint64_t));
572 
573 	(void) dof_add_lsect(ddo, &dofr, DOF_SECT_URELHDR,
574 	    sizeof (dof_secidx_t), 0, 0, sizeof (dof_relohdr_t));
575 
576 	if (nxr != 0 && dtp->dt_xlatemode == DT_XL_DYNAMIC) {
577 		(void) dof_add_lsect(ddo, dofs, DOF_SECT_PREXPORT,
578 		    sizeof (dof_secidx_t), 0, sizeof (dof_secidx_t),
579 		    sizeof (dof_secidx_t) * (nxr + 1));
580 	}
581 }
582 
583 static int
584 dof_hdr(dtrace_hdl_t *dtp, uint8_t dofversion, dof_hdr_t *hp)
585 {
586 	/*
587 	 * If our config values cannot fit in a uint8_t, we can't generate a
588 	 * DOF header since the values won't fit.  This can only happen if the
589 	 * user forcibly compiles a program with an artificial configuration.
590 	 */
591 	if (dtp->dt_conf.dtc_difversion > UINT8_MAX ||
592 	    dtp->dt_conf.dtc_difintregs > UINT8_MAX ||
593 	    dtp->dt_conf.dtc_diftupregs > UINT8_MAX)
594 		return (dt_set_errno(dtp, EOVERFLOW));
595 
596 	bzero(hp, sizeof (dof_hdr_t));
597 
598 	hp->dofh_ident[DOF_ID_MAG0] = DOF_MAG_MAG0;
599 	hp->dofh_ident[DOF_ID_MAG1] = DOF_MAG_MAG1;
600 	hp->dofh_ident[DOF_ID_MAG2] = DOF_MAG_MAG2;
601 	hp->dofh_ident[DOF_ID_MAG3] = DOF_MAG_MAG3;
602 
603 	if (dtp->dt_conf.dtc_ctfmodel == CTF_MODEL_LP64)
604 		hp->dofh_ident[DOF_ID_MODEL] = DOF_MODEL_LP64;
605 	else
606 		hp->dofh_ident[DOF_ID_MODEL] = DOF_MODEL_ILP32;
607 
608 	hp->dofh_ident[DOF_ID_ENCODING] = DOF_ENCODE_NATIVE;
609 	hp->dofh_ident[DOF_ID_VERSION] = dofversion;
610 	hp->dofh_ident[DOF_ID_DIFVERS] = dtp->dt_conf.dtc_difversion;
611 	hp->dofh_ident[DOF_ID_DIFIREG] = dtp->dt_conf.dtc_difintregs;
612 	hp->dofh_ident[DOF_ID_DIFTREG] = dtp->dt_conf.dtc_diftupregs;
613 
614 	hp->dofh_hdrsize = sizeof (dof_hdr_t);
615 	hp->dofh_secsize = sizeof (dof_sec_t);
616 	hp->dofh_secoff = sizeof (dof_hdr_t);
617 
618 	return (0);
619 }
620 
621 void *
622 dtrace_dof_create(dtrace_hdl_t *dtp, dtrace_prog_t *pgp, uint_t flags)
623 {
624 	dt_dof_t *ddo = &dtp->dt_dof;
625 
626 	const dtrace_ecbdesc_t *edp, *last;
627 	const dtrace_probedesc_t *pdp;
628 	const dtrace_actdesc_t *ap;
629 	const dt_stmt_t *stp;
630 
631 	uint_t maxacts = 0;
632 	uint_t maxfmt = 0;
633 
634 	dt_provider_t *pvp;
635 	dt_xlator_t *dxp;
636 	dof_actdesc_t *dofa;
637 	dof_sec_t *sp;
638 	size_t ssize, lsize;
639 	dof_hdr_t h;
640 
641 	dt_buf_t dof;
642 	char *fmt;
643 	uint_t i;
644 
645 	if (flags & ~DTRACE_D_MASK) {
646 		(void) dt_set_errno(dtp, EINVAL);
647 		return (NULL);
648 	}
649 
650 	flags |= dtp->dt_dflags;
651 
652 	if (dof_hdr(dtp, pgp->dp_dofversion, &h) != 0)
653 		return (NULL);
654 
655 	if (dt_dof_reset(dtp, pgp) != 0)
656 		return (NULL);
657 
658 	/*
659 	 * Iterate through the statement list computing the maximum number of
660 	 * actions and the maximum format string for allocating local buffers.
661 	 */
662 	for (last = NULL, stp = dt_list_next(&pgp->dp_stmts);
663 	    stp != NULL; stp = dt_list_next(stp), last = edp) {
664 
665 		dtrace_stmtdesc_t *sdp = stp->ds_desc;
666 		dtrace_actdesc_t *ap = sdp->dtsd_action;
667 
668 		if (sdp->dtsd_fmtdata != NULL) {
669 			i = dtrace_printf_format(dtp,
670 			    sdp->dtsd_fmtdata, NULL, 0);
671 			maxfmt = MAX(maxfmt, i);
672 		}
673 
674 		if ((edp = sdp->dtsd_ecbdesc) == last)
675 			continue; /* same ecb as previous statement */
676 
677 		for (i = 0, ap = edp->dted_action; ap; ap = ap->dtad_next)
678 			i++;
679 
680 		maxacts = MAX(maxacts, i);
681 	}
682 
683 	dofa = alloca(sizeof (dof_actdesc_t) * maxacts);
684 	fmt = alloca(maxfmt + 1);
685 
686 	ddo->ddo_strsec = dof_add_lsect(ddo, NULL, DOF_SECT_STRTAB, 1, 0, 0, 0);
687 	(void) dof_add_string(ddo, "");
688 
689 	/*
690 	 * If there are references to dynamic translators in the program, add
691 	 * an imported translator table entry for each referenced translator.
692 	 */
693 	if (pgp->dp_xrefslen != 0) {
694 		for (dxp = dt_list_next(&dtp->dt_xlators);
695 		    dxp != NULL; dxp = dt_list_next(dxp)) {
696 			if (dxp->dx_id < pgp->dp_xrefslen &&
697 			    pgp->dp_xrefs[dxp->dx_id] != NULL)
698 				dof_add_translator(ddo, dxp, DOF_SECT_XLIMPORT);
699 		}
700 	}
701 
702 	/*
703 	 * Now iterate through the statement list, creating the DOF section
704 	 * headers and data for each one and adding them to our buffers.
705 	 */
706 	for (last = NULL, stp = dt_list_next(&pgp->dp_stmts);
707 	    stp != NULL; stp = dt_list_next(stp), last = edp) {
708 
709 		dof_secidx_t probesec = DOF_SECIDX_NONE;
710 		dof_secidx_t prdsec = DOF_SECIDX_NONE;
711 		dof_secidx_t actsec = DOF_SECIDX_NONE;
712 
713 		const dt_stmt_t *next = stp;
714 		dtrace_stmtdesc_t *sdp = stp->ds_desc;
715 		dof_stridx_t strndx = 0;
716 		dof_probedesc_t dofp;
717 		dof_ecbdesc_t dofe;
718 		uint_t i;
719 
720 		if ((edp = stp->ds_desc->dtsd_ecbdesc) == last)
721 			continue; /* same ecb as previous statement */
722 
723 		pdp = &edp->dted_probe;
724 
725 		/*
726 		 * Add a DOF_SECT_PROBEDESC for the ECB's probe description,
727 		 * and copy the probe description strings into the string table.
728 		 */
729 		dofp.dofp_strtab = ddo->ddo_strsec;
730 		dofp.dofp_provider = dof_add_string(ddo, pdp->dtpd_provider);
731 		dofp.dofp_mod = dof_add_string(ddo, pdp->dtpd_mod);
732 		dofp.dofp_func = dof_add_string(ddo, pdp->dtpd_func);
733 		dofp.dofp_name = dof_add_string(ddo, pdp->dtpd_name);
734 		dofp.dofp_id = pdp->dtpd_id;
735 
736 		probesec = dof_add_lsect(ddo, &dofp, DOF_SECT_PROBEDESC,
737 		    sizeof (dof_secidx_t), 0,
738 		    sizeof (dof_probedesc_t), sizeof (dof_probedesc_t));
739 
740 		/*
741 		 * If there is a predicate DIFO associated with the ecbdesc,
742 		 * write out the DIFO sections and save the DIFO section index.
743 		 */
744 		if (edp->dted_pred.dtpdd_difo != NULL)
745 			prdsec = dof_add_difo(ddo, edp->dted_pred.dtpdd_difo);
746 
747 		/*
748 		 * Now iterate through the action list generating DIFOs as
749 		 * referenced therein and adding action descriptions to 'dofa'.
750 		 */
751 		for (i = 0, ap = edp->dted_action;
752 		    ap != NULL; ap = ap->dtad_next, i++) {
753 
754 			if (ap->dtad_difo != NULL) {
755 				dofa[i].dofa_difo =
756 				    dof_add_difo(ddo, ap->dtad_difo);
757 			} else
758 				dofa[i].dofa_difo = DOF_SECIDX_NONE;
759 
760 			/*
761 			 * If the first action in a statement has format data,
762 			 * add the format string to the global string table.
763 			 */
764 			if (sdp != NULL && ap == sdp->dtsd_action) {
765 				if (sdp->dtsd_fmtdata != NULL) {
766 					(void) dtrace_printf_format(dtp,
767 					    sdp->dtsd_fmtdata, fmt, maxfmt + 1);
768 					strndx = dof_add_string(ddo, fmt);
769 				} else
770 					strndx = 0; /* use dtad_arg instead */
771 
772 				if ((next = dt_list_next(next)) != NULL)
773 					sdp = next->ds_desc;
774 				else
775 					sdp = NULL;
776 			}
777 
778 			if (strndx != 0) {
779 				dofa[i].dofa_arg = strndx;
780 				dofa[i].dofa_strtab = ddo->ddo_strsec;
781 			} else {
782 				dofa[i].dofa_arg = ap->dtad_arg;
783 				dofa[i].dofa_strtab = DOF_SECIDX_NONE;
784 			}
785 
786 			dofa[i].dofa_kind = ap->dtad_kind;
787 			dofa[i].dofa_ntuple = ap->dtad_ntuple;
788 			dofa[i].dofa_uarg = ap->dtad_uarg;
789 		}
790 
791 		if (i > 0) {
792 			actsec = dof_add_lsect(ddo, dofa, DOF_SECT_ACTDESC,
793 			    sizeof (uint64_t), 0, sizeof (dof_actdesc_t),
794 			    sizeof (dof_actdesc_t) * i);
795 		}
796 
797 		/*
798 		 * Now finally, add the DOF_SECT_ECBDESC referencing all the
799 		 * previously created sub-sections.
800 		 */
801 		dofe.dofe_probes = probesec;
802 		dofe.dofe_pred = prdsec;
803 		dofe.dofe_actions = actsec;
804 		dofe.dofe_pad = 0;
805 		dofe.dofe_uarg = edp->dted_uarg;
806 
807 		(void) dof_add_lsect(ddo, &dofe, DOF_SECT_ECBDESC,
808 		    sizeof (uint64_t), 0, 0, sizeof (dof_ecbdesc_t));
809 	}
810 
811 	/*
812 	 * If any providers are user-defined, output DOF sections corresponding
813 	 * to the providers and the probes and arguments that they define.
814 	 */
815 	if (flags & DTRACE_D_PROBES) {
816 		for (pvp = dt_list_next(&dtp->dt_provlist);
817 		    pvp != NULL; pvp = dt_list_next(pvp))
818 			dof_add_provider(ddo, pvp);
819 	}
820 
821 	/*
822 	 * If we're not stripping unloadable sections, generate compiler
823 	 * comments and any other unloadable miscellany.
824 	 */
825 	if (!(flags & DTRACE_D_STRIP)) {
826 		(void) dof_add_usect(ddo, _dtrace_version, DOF_SECT_COMMENTS,
827 		    sizeof (char), 0, 0, strlen(_dtrace_version) + 1);
828 		(void) dof_add_usect(ddo, &dtp->dt_uts, DOF_SECT_UTSNAME,
829 		    sizeof (char), 0, 0, sizeof (struct utsname));
830 	}
831 
832 	/*
833 	 * Compute and fill in the appropriate values for the dof_hdr_t's
834 	 * dofh_secnum, dofh_loadsz, and dofh_filez values.
835 	 */
836 	h.dofh_secnum = ddo->ddo_nsecs;
837 	ssize = sizeof (h) + dt_buf_len(&ddo->ddo_secs);
838 
839 	h.dofh_loadsz = ssize +
840 	    dt_buf_len(&ddo->ddo_ldata) +
841 	    dt_buf_len(&ddo->ddo_strs);
842 
843 	if (dt_buf_len(&ddo->ddo_udata) != 0) {
844 		lsize = roundup(h.dofh_loadsz, sizeof (uint64_t));
845 		h.dofh_filesz = lsize + dt_buf_len(&ddo->ddo_udata);
846 	} else {
847 		lsize = h.dofh_loadsz;
848 		h.dofh_filesz = lsize;
849 	}
850 
851 	/*
852 	 * Set the global DOF_SECT_STRTAB's offset to be after the header,
853 	 * section headers, and other loadable data.  Since we're going to
854 	 * iterate over the buffer data directly, we must check for errors.
855 	 */
856 	if ((i = dt_buf_error(&ddo->ddo_secs)) != 0) {
857 		(void) dt_set_errno(dtp, i);
858 		return (NULL);
859 	}
860 
861 	sp = dt_buf_ptr(&ddo->ddo_secs);
862 	assert(sp[ddo->ddo_strsec].dofs_type == DOF_SECT_STRTAB);
863 	assert(ssize == sizeof (h) + sizeof (dof_sec_t) * ddo->ddo_nsecs);
864 
865 	sp[ddo->ddo_strsec].dofs_offset = ssize + dt_buf_len(&ddo->ddo_ldata);
866 	sp[ddo->ddo_strsec].dofs_size = dt_buf_len(&ddo->ddo_strs);
867 
868 	/*
869 	 * Now relocate all the other section headers by adding the appropriate
870 	 * delta to their respective dofs_offset values.
871 	 */
872 	for (i = 0; i < ddo->ddo_nsecs; i++, sp++) {
873 		if (i == ddo->ddo_strsec)
874 			continue; /* already relocated above */
875 
876 		if (sp->dofs_flags & DOF_SECF_LOAD)
877 			sp->dofs_offset += ssize;
878 		else
879 			sp->dofs_offset += lsize;
880 	}
881 
882 	/*
883 	 * Finally, assemble the complete in-memory DOF buffer by writing the
884 	 * header and then concatenating all our buffers.  dt_buf_concat() will
885 	 * propagate any errors and cause dt_buf_claim() to return NULL.
886 	 */
887 	dt_buf_create(dtp, &dof, "dof", h.dofh_filesz);
888 
889 	dt_buf_write(dtp, &dof, &h, sizeof (h), sizeof (uint64_t));
890 	dt_buf_concat(dtp, &dof, &ddo->ddo_secs, sizeof (uint64_t));
891 	dt_buf_concat(dtp, &dof, &ddo->ddo_ldata, sizeof (uint64_t));
892 	dt_buf_concat(dtp, &dof, &ddo->ddo_strs, sizeof (char));
893 	dt_buf_concat(dtp, &dof, &ddo->ddo_udata, sizeof (uint64_t));
894 
895 	return (dt_buf_claim(dtp, &dof));
896 }
897 
898 void
899 dtrace_dof_destroy(dtrace_hdl_t *dtp, void *dof)
900 {
901 	dt_free(dtp, dof);
902 }
903 
904 void *
905 dtrace_getopt_dof(dtrace_hdl_t *dtp)
906 {
907 	dof_hdr_t *dof;
908 	dof_sec_t *sec;
909 	dof_optdesc_t *dofo;
910 	int i, nopts = 0, len = sizeof (dof_hdr_t) +
911 	    roundup(sizeof (dof_sec_t), sizeof (uint64_t));
912 
913 	for (i = 0; i < DTRACEOPT_MAX; i++) {
914 		if (dtp->dt_options[i] != DTRACEOPT_UNSET)
915 			nopts++;
916 	}
917 
918 	len += sizeof (dof_optdesc_t) * nopts;
919 
920 	if ((dof = dt_zalloc(dtp, len)) == NULL ||
921 	    dof_hdr(dtp, DOF_VERSION, dof) != 0) {
922 		dt_free(dtp, dof);
923 		return (NULL);
924 	}
925 
926 	dof->dofh_secnum = 1;	/* only DOF_SECT_OPTDESC */
927 	dof->dofh_loadsz = len;
928 	dof->dofh_filesz = len;
929 
930 	/*
931 	 * Fill in the option section header...
932 	 */
933 	sec = (dof_sec_t *)((uintptr_t)dof + sizeof (dof_hdr_t));
934 	sec->dofs_type = DOF_SECT_OPTDESC;
935 	sec->dofs_align = sizeof (uint64_t);
936 	sec->dofs_flags = DOF_SECF_LOAD;
937 	sec->dofs_entsize = sizeof (dof_optdesc_t);
938 
939 	dofo = (dof_optdesc_t *)((uintptr_t)sec +
940 	    roundup(sizeof (dof_sec_t), sizeof (uint64_t)));
941 
942 	sec->dofs_offset = (uintptr_t)dofo - (uintptr_t)dof;
943 	sec->dofs_size = sizeof (dof_optdesc_t) * nopts;
944 
945 	for (i = 0; i < DTRACEOPT_MAX; i++) {
946 		if (dtp->dt_options[i] == DTRACEOPT_UNSET)
947 			continue;
948 
949 		dofo->dofo_option = i;
950 		dofo->dofo_strtab = DOF_SECIDX_NONE;
951 		dofo->dofo_value = dtp->dt_options[i];
952 		dofo++;
953 	}
954 
955 	return (dof);
956 }
957 
958 void *
959 dtrace_geterr_dof(dtrace_hdl_t *dtp)
960 {
961 	if (dtp->dt_errprog != NULL)
962 		return (dtrace_dof_create(dtp, dtp->dt_errprog, 0));
963 
964 	(void) dt_set_errno(dtp, EDT_BADERROR);
965 	return (NULL);
966 }
967