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  * Copyright (c) 2011 by Delphix. All rights reserved.
25  * Copyright (c) 2013, Joyent, Inc. All rights reserved.
26  */
27 
28 #include <sys/types.h>
29 #ifdef illumos
30 #include <sys/sysmacros.h>
31 #endif
32 
33 #include <strings.h>
34 #ifdef illumos
35 #include <alloca.h>
36 #endif
37 #include <assert.h>
38 #include <stdlib.h>
39 #include <errno.h>
40 #include <limits.h>
41 
42 #include <dt_impl.h>
43 #include <dt_strtab.h>
44 #include <dt_program.h>
45 #include <dt_provider.h>
46 #include <dt_xlator.h>
47 #include <dt_dof.h>
48 
49 void
50 dt_dof_init(dtrace_hdl_t *dtp)
51 {
52 	dt_dof_t *ddo = &dtp->dt_dof;
53 
54 	ddo->ddo_hdl = dtp;
55 	ddo->ddo_nsecs = 0;
56 	ddo->ddo_strsec = DOF_SECIDX_NONE;
57 	ddo->ddo_xlimport = NULL;
58 	ddo->ddo_xlexport = NULL;
59 
60 	dt_buf_create(dtp, &ddo->ddo_secs, "section headers", 0);
61 	dt_buf_create(dtp, &ddo->ddo_strs, "string table", 0);
62 	dt_buf_create(dtp, &ddo->ddo_ldata, "loadable data", 0);
63 	dt_buf_create(dtp, &ddo->ddo_udata, "unloadable data", 0);
64 
65 	dt_buf_create(dtp, &ddo->ddo_probes, "probe data", 0);
66 	dt_buf_create(dtp, &ddo->ddo_args, "probe args", 0);
67 	dt_buf_create(dtp, &ddo->ddo_offs, "probe offs", 0);
68 	dt_buf_create(dtp, &ddo->ddo_enoffs, "probe is-enabled offs", 0);
69 	dt_buf_create(dtp, &ddo->ddo_rels, "probe rels", 0);
70 
71 	dt_buf_create(dtp, &ddo->ddo_xlms, "xlate members", 0);
72 }
73 
74 void
75 dt_dof_fini(dtrace_hdl_t *dtp)
76 {
77 	dt_dof_t *ddo = &dtp->dt_dof;
78 
79 	dt_free(dtp, ddo->ddo_xlimport);
80 	dt_free(dtp, ddo->ddo_xlexport);
81 
82 	dt_buf_destroy(dtp, &ddo->ddo_secs);
83 	dt_buf_destroy(dtp, &ddo->ddo_strs);
84 	dt_buf_destroy(dtp, &ddo->ddo_ldata);
85 	dt_buf_destroy(dtp, &ddo->ddo_udata);
86 
87 	dt_buf_destroy(dtp, &ddo->ddo_probes);
88 	dt_buf_destroy(dtp, &ddo->ddo_args);
89 	dt_buf_destroy(dtp, &ddo->ddo_offs);
90 	dt_buf_destroy(dtp, &ddo->ddo_enoffs);
91 	dt_buf_destroy(dtp, &ddo->ddo_rels);
92 
93 	dt_buf_destroy(dtp, &ddo->ddo_xlms);
94 }
95 
96 static int
97 dt_dof_reset(dtrace_hdl_t *dtp, dtrace_prog_t *pgp)
98 {
99 	dt_dof_t *ddo = &dtp->dt_dof;
100 	uint_t i, nx = dtp->dt_xlatorid;
101 
102 	assert(ddo->ddo_hdl == dtp);
103 	ddo->ddo_pgp = pgp;
104 
105 	ddo->ddo_nsecs = 0;
106 	ddo->ddo_strsec = DOF_SECIDX_NONE;
107 
108 	dt_free(dtp, ddo->ddo_xlimport);
109 	dt_free(dtp, ddo->ddo_xlexport);
110 
111 	ddo->ddo_xlimport = dt_alloc(dtp, sizeof (dof_secidx_t) * nx);
112 	ddo->ddo_xlexport = dt_alloc(dtp, sizeof (dof_secidx_t) * nx);
113 
114 	if (nx != 0 && (ddo->ddo_xlimport == NULL || ddo->ddo_xlexport == NULL))
115 		return (-1); /* errno is set for us */
116 
117 	for (i = 0; i < nx; i++) {
118 		ddo->ddo_xlimport[i] = DOF_SECIDX_NONE;
119 		ddo->ddo_xlexport[i] = DOF_SECIDX_NONE;
120 	}
121 
122 	dt_buf_reset(dtp, &ddo->ddo_secs);
123 	dt_buf_reset(dtp, &ddo->ddo_strs);
124 	dt_buf_reset(dtp, &ddo->ddo_ldata);
125 	dt_buf_reset(dtp, &ddo->ddo_udata);
126 
127 	dt_buf_reset(dtp, &ddo->ddo_probes);
128 	dt_buf_reset(dtp, &ddo->ddo_args);
129 	dt_buf_reset(dtp, &ddo->ddo_offs);
130 	dt_buf_reset(dtp, &ddo->ddo_enoffs);
131 	dt_buf_reset(dtp, &ddo->ddo_rels);
132 
133 	dt_buf_reset(dtp, &ddo->ddo_xlms);
134 	return (0);
135 }
136 
137 /*
138  * Add a loadable DOF section to the file using the specified data buffer and
139  * the specified DOF section attributes.  DOF_SECF_LOAD must be set in flags.
140  * If 'data' is NULL, the caller is responsible for manipulating the ldata buf.
141  */
142 static dof_secidx_t
143 dof_add_lsect(dt_dof_t *ddo, const void *data, uint32_t type,
144     uint32_t align, uint32_t flags, uint32_t entsize, uint64_t size)
145 {
146 	dtrace_hdl_t *dtp = ddo->ddo_hdl;
147 	dof_sec_t s;
148 
149 	s.dofs_type = type;
150 	s.dofs_align = align;
151 	s.dofs_flags = flags | DOF_SECF_LOAD;
152 	s.dofs_entsize = entsize;
153 	s.dofs_offset = dt_buf_offset(&ddo->ddo_ldata, align);
154 	s.dofs_size = size;
155 
156 	dt_buf_write(dtp, &ddo->ddo_secs, &s, sizeof (s), sizeof (uint64_t));
157 
158 	if (data != NULL)
159 		dt_buf_write(dtp, &ddo->ddo_ldata, data, size, align);
160 
161 	return (ddo->ddo_nsecs++);
162 }
163 
164 /*
165  * Add an unloadable DOF section to the file using the specified data buffer
166  * and DOF section attributes.  DOF_SECF_LOAD must *not* be set in flags.
167  * If 'data' is NULL, the caller is responsible for manipulating the udata buf.
168  */
169 static dof_secidx_t
170 dof_add_usect(dt_dof_t *ddo, const void *data, uint32_t type,
171     uint32_t align, uint32_t flags, uint32_t entsize, uint64_t size)
172 {
173 	dtrace_hdl_t *dtp = ddo->ddo_hdl;
174 	dof_sec_t s;
175 
176 	s.dofs_type = type;
177 	s.dofs_align = align;
178 	s.dofs_flags = flags & ~DOF_SECF_LOAD;
179 	s.dofs_entsize = entsize;
180 	s.dofs_offset = dt_buf_offset(&ddo->ddo_udata, align);
181 	s.dofs_size = size;
182 
183 	dt_buf_write(dtp, &ddo->ddo_secs, &s, sizeof (s), sizeof (uint64_t));
184 
185 	if (data != NULL)
186 		dt_buf_write(dtp, &ddo->ddo_udata, data, size, align);
187 
188 	return (ddo->ddo_nsecs++);
189 }
190 
191 /*
192  * Add a string to the global string table associated with the DOF.  The offset
193  * of the string is returned as an index into the string table.
194  */
195 static dof_stridx_t
196 dof_add_string(dt_dof_t *ddo, const char *s)
197 {
198 	dt_buf_t *bp = &ddo->ddo_strs;
199 	dof_stridx_t i = dt_buf_len(bp);
200 
201 	if (i != 0 && (s == NULL || *s == '\0'))
202 		return (0); /* string table has \0 at offset 0 */
203 
204 	dt_buf_write(ddo->ddo_hdl, bp, s, strlen(s) + 1, sizeof (char));
205 	return (i);
206 }
207 
208 static dof_attr_t
209 dof_attr(const dtrace_attribute_t *ap)
210 {
211 	return (DOF_ATTR(ap->dtat_name, ap->dtat_data, ap->dtat_class));
212 }
213 
214 static dof_secidx_t
215 dof_add_difo(dt_dof_t *ddo, const dtrace_difo_t *dp)
216 {
217 	dof_secidx_t dsecs[5]; /* enough for all possible DIFO sections */
218 	uint_t nsecs = 0;
219 
220 	dof_difohdr_t *dofd;
221 	dof_relohdr_t dofr;
222 	dof_secidx_t relsec;
223 
224 	dof_secidx_t strsec = DOF_SECIDX_NONE;
225 	dof_secidx_t intsec = DOF_SECIDX_NONE;
226 	dof_secidx_t hdrsec = DOF_SECIDX_NONE;
227 
228 	if (dp->dtdo_buf != NULL) {
229 		dsecs[nsecs++] = dof_add_lsect(ddo, dp->dtdo_buf,
230 		    DOF_SECT_DIF, sizeof (dif_instr_t), 0,
231 		    sizeof (dif_instr_t), sizeof (dif_instr_t) * dp->dtdo_len);
232 	}
233 
234 	if (dp->dtdo_inttab != NULL) {
235 		dsecs[nsecs++] = intsec = dof_add_lsect(ddo, dp->dtdo_inttab,
236 		    DOF_SECT_INTTAB, sizeof (uint64_t), 0,
237 		    sizeof (uint64_t), sizeof (uint64_t) * dp->dtdo_intlen);
238 	}
239 
240 	if (dp->dtdo_strtab != NULL) {
241 		dsecs[nsecs++] = strsec = dof_add_lsect(ddo, dp->dtdo_strtab,
242 		    DOF_SECT_STRTAB, sizeof (char), 0, 0, dp->dtdo_strlen);
243 	}
244 
245 	if (dp->dtdo_vartab != NULL) {
246 		dsecs[nsecs++] = dof_add_lsect(ddo, dp->dtdo_vartab,
247 		    DOF_SECT_VARTAB, sizeof (uint_t), 0, sizeof (dtrace_difv_t),
248 		    sizeof (dtrace_difv_t) * dp->dtdo_varlen);
249 	}
250 
251 	if (dp->dtdo_xlmtab != NULL) {
252 		dof_xlref_t *xlt, *xlp;
253 		dt_node_t **pnp;
254 
255 		xlt = alloca(sizeof (dof_xlref_t) * dp->dtdo_xlmlen);
256 		pnp = dp->dtdo_xlmtab;
257 
258 		/*
259 		 * dtdo_xlmtab contains pointers to the translator members.
260 		 * The translator itself is in sect ddo_xlimport[dxp->dx_id].
261 		 * The XLMEMBERS entries are in order by their dn_membid, so
262 		 * the member section offset is the population count of bits
263 		 * in ddo_pgp->dp_xlrefs[] up to and not including dn_membid.
264 		 */
265 		for (xlp = xlt; xlp < xlt + dp->dtdo_xlmlen; xlp++) {
266 			dt_node_t *dnp = *pnp++;
267 			dt_xlator_t *dxp = dnp->dn_membexpr->dn_xlator;
268 
269 			xlp->dofxr_xlator = ddo->ddo_xlimport[dxp->dx_id];
270 			xlp->dofxr_member = dt_popcb(
271 			    ddo->ddo_pgp->dp_xrefs[dxp->dx_id], dnp->dn_membid);
272 			xlp->dofxr_argn = (uint32_t)dxp->dx_arg;
273 		}
274 
275 		dsecs[nsecs++] = dof_add_lsect(ddo, xlt, DOF_SECT_XLTAB,
276 		    sizeof (dof_secidx_t), 0, sizeof (dof_xlref_t),
277 		    sizeof (dof_xlref_t) * dp->dtdo_xlmlen);
278 	}
279 
280 	/*
281 	 * Copy the return type and the array of section indices that form the
282 	 * DIFO into a single dof_difohdr_t and then add DOF_SECT_DIFOHDR.
283 	 */
284 	assert(nsecs <= sizeof (dsecs) / sizeof (dsecs[0]));
285 	dofd = alloca(sizeof (dtrace_diftype_t) + sizeof (dsecs));
286 	bcopy(&dp->dtdo_rtype, &dofd->dofd_rtype, sizeof (dtrace_diftype_t));
287 	bcopy(dsecs, &dofd->dofd_links, sizeof (dof_secidx_t) * nsecs);
288 
289 	hdrsec = dof_add_lsect(ddo, dofd, DOF_SECT_DIFOHDR,
290 	    sizeof (dof_secidx_t), 0, 0,
291 	    sizeof (dtrace_diftype_t) + sizeof (dof_secidx_t) * nsecs);
292 
293 	/*
294 	 * Add any other sections related to dtrace_difo_t.  These are not
295 	 * referenced in dof_difohdr_t because they are not used by emulation.
296 	 */
297 	if (dp->dtdo_kreltab != NULL) {
298 		relsec = dof_add_lsect(ddo, dp->dtdo_kreltab, DOF_SECT_RELTAB,
299 		    sizeof (uint64_t), 0, sizeof (dof_relodesc_t),
300 		    sizeof (dof_relodesc_t) * dp->dtdo_krelen);
301 
302 		/*
303 		 * This code assumes the target of all relocations is the
304 		 * integer table 'intsec' (DOF_SECT_INTTAB).  If other sections
305 		 * need relocation in the future this will need to change.
306 		 */
307 		dofr.dofr_strtab = strsec;
308 		dofr.dofr_relsec = relsec;
309 		dofr.dofr_tgtsec = intsec;
310 
311 		(void) dof_add_lsect(ddo, &dofr, DOF_SECT_KRELHDR,
312 		    sizeof (dof_secidx_t), 0, 0, sizeof (dof_relohdr_t));
313 	}
314 
315 	if (dp->dtdo_ureltab != NULL) {
316 		relsec = dof_add_lsect(ddo, dp->dtdo_ureltab, DOF_SECT_RELTAB,
317 		    sizeof (uint64_t), 0, sizeof (dof_relodesc_t),
318 		    sizeof (dof_relodesc_t) * dp->dtdo_urelen);
319 
320 		/*
321 		 * This code assumes the target of all relocations is the
322 		 * integer table 'intsec' (DOF_SECT_INTTAB).  If other sections
323 		 * need relocation in the future this will need to change.
324 		 */
325 		dofr.dofr_strtab = strsec;
326 		dofr.dofr_relsec = relsec;
327 		dofr.dofr_tgtsec = intsec;
328 
329 		(void) dof_add_lsect(ddo, &dofr, DOF_SECT_URELHDR,
330 		    sizeof (dof_secidx_t), 0, 0, sizeof (dof_relohdr_t));
331 	}
332 
333 	return (hdrsec);
334 }
335 
336 static void
337 dof_add_translator(dt_dof_t *ddo, const dt_xlator_t *dxp, uint_t type)
338 {
339 	dtrace_hdl_t *dtp = ddo->ddo_hdl;
340 	dof_xlmember_t dofxm;
341 	dof_xlator_t dofxl;
342 	dof_secidx_t *xst;
343 
344 	char buf[DT_TYPE_NAMELEN];
345 	dt_node_t *dnp;
346 	uint_t i = 0;
347 
348 	assert(type == DOF_SECT_XLIMPORT || type == DOF_SECT_XLEXPORT);
349 	xst = type == DOF_SECT_XLIMPORT ? ddo->ddo_xlimport : ddo->ddo_xlexport;
350 
351 	if (xst[dxp->dx_id] != DOF_SECIDX_NONE)
352 		return; /* translator has already been emitted */
353 
354 	dt_buf_reset(dtp, &ddo->ddo_xlms);
355 
356 	/*
357 	 * Generate an array of dof_xlmember_t's into ddo_xlms.  If we are
358 	 * importing the translator, add only those members referenced by the
359 	 * program and set the dofxm_difo reference of each member to NONE.  If
360 	 * we're exporting the translator, add all members and a DIFO for each.
361 	 */
362 	for (dnp = dxp->dx_members; dnp != NULL; dnp = dnp->dn_list, i++) {
363 		if (type == DOF_SECT_XLIMPORT) {
364 			if (!BT_TEST(ddo->ddo_pgp->dp_xrefs[dxp->dx_id], i))
365 				continue; /* member is not referenced */
366 			dofxm.dofxm_difo = DOF_SECIDX_NONE;
367 		} else {
368 			dofxm.dofxm_difo = dof_add_difo(ddo,
369 			    dxp->dx_membdif[dnp->dn_membid]);
370 		}
371 
372 		dofxm.dofxm_name = dof_add_string(ddo, dnp->dn_membname);
373 		dt_node_diftype(dtp, dnp, &dofxm.dofxm_type);
374 
375 		dt_buf_write(dtp, &ddo->ddo_xlms,
376 		    &dofxm, sizeof (dofxm), sizeof (uint32_t));
377 	}
378 
379 	dofxl.dofxl_members = dof_add_lsect(ddo, NULL, DOF_SECT_XLMEMBERS,
380 	    sizeof (uint32_t), 0, sizeof (dofxm), dt_buf_len(&ddo->ddo_xlms));
381 
382 	dt_buf_concat(dtp, &ddo->ddo_ldata, &ddo->ddo_xlms, sizeof (uint32_t));
383 
384 	dofxl.dofxl_strtab = ddo->ddo_strsec;
385 	dofxl.dofxl_argv = dof_add_string(ddo, ctf_type_name(
386 	    dxp->dx_src_ctfp, dxp->dx_src_type, buf, sizeof (buf)));
387 	dofxl.dofxl_argc = 1;
388 	dofxl.dofxl_type = dof_add_string(ddo, ctf_type_name(
389 	    dxp->dx_dst_ctfp, dxp->dx_dst_type, buf, sizeof (buf)));
390 	dofxl.dofxl_attr = dof_attr(&dxp->dx_souid.di_attr);
391 
392 	xst[dxp->dx_id] = dof_add_lsect(ddo, &dofxl, type,
393 	    sizeof (uint32_t), 0, 0, sizeof (dofxl));
394 }
395 
396 /*ARGSUSED*/
397 static int
398 dof_add_probe(dt_idhash_t *dhp, dt_ident_t *idp, void *data)
399 {
400 	dt_dof_t *ddo = data;
401 	dtrace_hdl_t *dtp = ddo->ddo_hdl;
402 	dt_probe_t *prp = idp->di_data;
403 
404 	dof_probe_t dofpr;
405 	dof_relodesc_t dofr;
406 	dt_probe_instance_t *pip;
407 	dt_node_t *dnp;
408 
409 	char buf[DT_TYPE_NAMELEN];
410 	uint_t i;
411 
412 	dofpr.dofpr_addr = 0;
413 	dofpr.dofpr_name = dof_add_string(ddo, prp->pr_name);
414 	dofpr.dofpr_nargv = dt_buf_len(&ddo->ddo_strs);
415 
416 	for (dnp = prp->pr_nargs; dnp != NULL; dnp = dnp->dn_list) {
417 		(void) dof_add_string(ddo, ctf_type_name(dnp->dn_ctfp,
418 		    dnp->dn_type, buf, sizeof (buf)));
419 	}
420 
421 	dofpr.dofpr_xargv = dt_buf_len(&ddo->ddo_strs);
422 
423 	for (dnp = prp->pr_xargs; dnp != NULL; dnp = dnp->dn_list) {
424 		(void) dof_add_string(ddo, ctf_type_name(dnp->dn_ctfp,
425 		    dnp->dn_type, buf, sizeof (buf)));
426 	}
427 
428 	dofpr.dofpr_argidx = dt_buf_len(&ddo->ddo_args) / sizeof (uint8_t);
429 
430 	for (i = 0; i < prp->pr_xargc; i++) {
431 		dt_buf_write(dtp, &ddo->ddo_args, &prp->pr_mapping[i],
432 		    sizeof (uint8_t), sizeof (uint8_t));
433 	}
434 
435 	dofpr.dofpr_nargc = prp->pr_nargc;
436 	dofpr.dofpr_xargc = prp->pr_xargc;
437 	dofpr.dofpr_pad1 = 0;
438 	dofpr.dofpr_pad2 = 0;
439 
440 	for (pip = prp->pr_inst; pip != NULL; pip = pip->pi_next) {
441 		dt_dprintf("adding probe for %s:%s\n", pip->pi_fname,
442 		    prp->pr_name);
443 
444 		dofpr.dofpr_func = dof_add_string(ddo, pip->pi_fname);
445 
446 		/*
447 		 * There should be one probe offset or is-enabled probe offset
448 		 * or else this probe instance won't have been created. The
449 		 * kernel will reject DOF which has a probe with no offsets.
450 		 */
451 		assert(pip->pi_noffs + pip->pi_nenoffs > 0);
452 
453 		dofpr.dofpr_offidx =
454 		    dt_buf_len(&ddo->ddo_offs) / sizeof (uint32_t);
455 		dofpr.dofpr_noffs = pip->pi_noffs;
456 		dt_buf_write(dtp, &ddo->ddo_offs, pip->pi_offs,
457 		    pip->pi_noffs * sizeof (uint32_t), sizeof (uint32_t));
458 
459 		dofpr.dofpr_enoffidx =
460 		    dt_buf_len(&ddo->ddo_enoffs) / sizeof (uint32_t);
461 		dofpr.dofpr_nenoffs = pip->pi_nenoffs;
462 		dt_buf_write(dtp, &ddo->ddo_enoffs, pip->pi_enoffs,
463 		    pip->pi_nenoffs * sizeof (uint32_t), sizeof (uint32_t));
464 
465 		dofr.dofr_name = dof_add_string(ddo, pip->pi_rname);
466 		dofr.dofr_type = DOF_RELO_DOFREL;
467 		dofr.dofr_offset = dt_buf_len(&ddo->ddo_probes);
468 		dofr.dofr_data = 0;
469 
470 		dt_buf_write(dtp, &ddo->ddo_rels, &dofr,
471 		    sizeof (dofr), sizeof (uint64_t));
472 
473 		dt_buf_write(dtp, &ddo->ddo_probes, &dofpr,
474 		    sizeof (dofpr), sizeof (uint64_t));
475 	}
476 
477 	return (0);
478 }
479 
480 static int
481 dof_add_provider(dt_dof_t *ddo, const dt_provider_t *pvp)
482 {
483 	dtrace_hdl_t *dtp = ddo->ddo_hdl;
484 	dof_provider_t dofpv;
485 	dof_relohdr_t dofr;
486 	dof_secidx_t *dofs;
487 	ulong_t xr, nxr;
488 	size_t sz;
489 	id_t i;
490 
491 	if (pvp->pv_flags & DT_PROVIDER_IMPL) {
492 		/*
493 		 * ignore providers that are exported by dtrace(7D)
494 		 */
495 		return (0);
496 	}
497 
498 	nxr = dt_popcb(pvp->pv_xrefs, pvp->pv_xrmax);
499 	dofs = alloca(sizeof (dof_secidx_t) * (nxr + 1));
500 	xr = 1; /* reserve dofs[0] for the provider itself */
501 
502 	/*
503 	 * For each translator referenced by the provider (pv_xrefs), emit an
504 	 * exported translator section for it if one hasn't been created yet.
505 	 */
506 	for (i = 0; i < pvp->pv_xrmax; i++) {
507 		if (BT_TEST(pvp->pv_xrefs, i) &&
508 		    dtp->dt_xlatemode == DT_XL_DYNAMIC) {
509 			dof_add_translator(ddo,
510 			    dt_xlator_lookup_id(dtp, i), DOF_SECT_XLEXPORT);
511 			dofs[xr++] = ddo->ddo_xlexport[i];
512 		}
513 	}
514 
515 	dt_buf_reset(dtp, &ddo->ddo_probes);
516 	dt_buf_reset(dtp, &ddo->ddo_args);
517 	dt_buf_reset(dtp, &ddo->ddo_offs);
518 	dt_buf_reset(dtp, &ddo->ddo_enoffs);
519 	dt_buf_reset(dtp, &ddo->ddo_rels);
520 
521 	(void) dt_idhash_iter(pvp->pv_probes, dof_add_probe, ddo);
522 
523 	if (dt_buf_len(&ddo->ddo_probes) == 0)
524 		return (dt_set_errno(dtp, EDT_NOPROBES));
525 
526 	dofpv.dofpv_probes = dof_add_lsect(ddo, NULL, DOF_SECT_PROBES,
527 	    sizeof (uint64_t), 0, sizeof (dof_probe_t),
528 	    dt_buf_len(&ddo->ddo_probes));
529 
530 	dt_buf_concat(dtp, &ddo->ddo_ldata,
531 	    &ddo->ddo_probes, sizeof (uint64_t));
532 
533 	dofpv.dofpv_prargs = dof_add_lsect(ddo, NULL, DOF_SECT_PRARGS,
534 	    sizeof (uint8_t), 0, sizeof (uint8_t), dt_buf_len(&ddo->ddo_args));
535 
536 	dt_buf_concat(dtp, &ddo->ddo_ldata, &ddo->ddo_args, sizeof (uint8_t));
537 
538 	dofpv.dofpv_proffs = dof_add_lsect(ddo, NULL, DOF_SECT_PROFFS,
539 	    sizeof (uint_t), 0, sizeof (uint_t), dt_buf_len(&ddo->ddo_offs));
540 
541 	dt_buf_concat(dtp, &ddo->ddo_ldata, &ddo->ddo_offs, sizeof (uint_t));
542 
543 	if ((sz = dt_buf_len(&ddo->ddo_enoffs)) != 0) {
544 		dofpv.dofpv_prenoffs = dof_add_lsect(ddo, NULL,
545 		    DOF_SECT_PRENOFFS, sizeof (uint_t), 0, sizeof (uint_t), sz);
546 	} else {
547 		dofpv.dofpv_prenoffs = DOF_SECT_NONE;
548 	}
549 
550 	dt_buf_concat(dtp, &ddo->ddo_ldata, &ddo->ddo_enoffs, sizeof (uint_t));
551 
552 	dofpv.dofpv_strtab = ddo->ddo_strsec;
553 	dofpv.dofpv_name = dof_add_string(ddo, pvp->pv_desc.dtvd_name);
554 
555 	dofpv.dofpv_provattr = dof_attr(&pvp->pv_desc.dtvd_attr.dtpa_provider);
556 	dofpv.dofpv_modattr = dof_attr(&pvp->pv_desc.dtvd_attr.dtpa_mod);
557 	dofpv.dofpv_funcattr = dof_attr(&pvp->pv_desc.dtvd_attr.dtpa_func);
558 	dofpv.dofpv_nameattr = dof_attr(&pvp->pv_desc.dtvd_attr.dtpa_name);
559 	dofpv.dofpv_argsattr = dof_attr(&pvp->pv_desc.dtvd_attr.dtpa_args);
560 
561 	dofs[0] = dof_add_lsect(ddo, &dofpv, DOF_SECT_PROVIDER,
562 	    sizeof (dof_secidx_t), 0, 0, sizeof (dof_provider_t));
563 
564 	dofr.dofr_strtab = dofpv.dofpv_strtab;
565 	dofr.dofr_tgtsec = dofpv.dofpv_probes;
566 	dofr.dofr_relsec = dof_add_lsect(ddo, NULL, DOF_SECT_RELTAB,
567 	    sizeof (uint64_t), 0, sizeof (dof_relodesc_t),
568 	    dt_buf_len(&ddo->ddo_rels));
569 
570 	dt_buf_concat(dtp, &ddo->ddo_ldata, &ddo->ddo_rels, sizeof (uint64_t));
571 
572 	(void) dof_add_lsect(ddo, &dofr, DOF_SECT_URELHDR,
573 	    sizeof (dof_secidx_t), 0, 0, sizeof (dof_relohdr_t));
574 
575 	if (nxr != 0 && dtp->dt_xlatemode == DT_XL_DYNAMIC) {
576 		(void) dof_add_lsect(ddo, dofs, DOF_SECT_PREXPORT,
577 		    sizeof (dof_secidx_t), 0, sizeof (dof_secidx_t),
578 		    sizeof (dof_secidx_t) * (nxr + 1));
579 	}
580 
581 	return (0);
582 }
583 
584 static int
585 dof_hdr(dtrace_hdl_t *dtp, uint8_t dofversion, dof_hdr_t *hp)
586 {
587 	/*
588 	 * If our config values cannot fit in a uint8_t, we can't generate a
589 	 * DOF header since the values won't fit.  This can only happen if the
590 	 * user forcibly compiles a program with an artificial configuration.
591 	 */
592 	if (dtp->dt_conf.dtc_difversion > UINT8_MAX ||
593 	    dtp->dt_conf.dtc_difintregs > UINT8_MAX ||
594 	    dtp->dt_conf.dtc_diftupregs > UINT8_MAX)
595 		return (dt_set_errno(dtp, EOVERFLOW));
596 
597 	bzero(hp, sizeof (dof_hdr_t));
598 
599 	hp->dofh_ident[DOF_ID_MAG0] = DOF_MAG_MAG0;
600 	hp->dofh_ident[DOF_ID_MAG1] = DOF_MAG_MAG1;
601 	hp->dofh_ident[DOF_ID_MAG2] = DOF_MAG_MAG2;
602 	hp->dofh_ident[DOF_ID_MAG3] = DOF_MAG_MAG3;
603 
604 	if (dtp->dt_conf.dtc_ctfmodel == CTF_MODEL_LP64)
605 		hp->dofh_ident[DOF_ID_MODEL] = DOF_MODEL_LP64;
606 	else
607 		hp->dofh_ident[DOF_ID_MODEL] = DOF_MODEL_ILP32;
608 
609 	hp->dofh_ident[DOF_ID_ENCODING] = DOF_ENCODE_NATIVE;
610 	hp->dofh_ident[DOF_ID_VERSION] = dofversion;
611 	hp->dofh_ident[DOF_ID_DIFVERS] = dtp->dt_conf.dtc_difversion;
612 	hp->dofh_ident[DOF_ID_DIFIREG] = dtp->dt_conf.dtc_difintregs;
613 	hp->dofh_ident[DOF_ID_DIFTREG] = dtp->dt_conf.dtc_diftupregs;
614 
615 	hp->dofh_hdrsize = sizeof (dof_hdr_t);
616 	hp->dofh_secsize = sizeof (dof_sec_t);
617 	hp->dofh_secoff = sizeof (dof_hdr_t);
618 
619 	return (0);
620 }
621 
622 void *
623 dtrace_dof_create(dtrace_hdl_t *dtp, dtrace_prog_t *pgp, uint_t flags)
624 {
625 	dt_dof_t *ddo = &dtp->dt_dof;
626 
627 	const dtrace_ecbdesc_t *edp, *last;
628 	const dtrace_probedesc_t *pdp;
629 	const dtrace_actdesc_t *ap;
630 	const dt_stmt_t *stp;
631 
632 	uint_t maxacts = 0;
633 	uint_t maxfmt = 0;
634 
635 	dt_provider_t *pvp;
636 	dt_xlator_t *dxp;
637 	dof_actdesc_t *dofa;
638 	dof_sec_t *sp;
639 	size_t ssize, lsize;
640 	dof_hdr_t h;
641 
642 	dt_buf_t dof;
643 	char *fmt;
644 	uint_t i;
645 
646 	if (flags & ~DTRACE_D_MASK) {
647 		(void) dt_set_errno(dtp, EINVAL);
648 		return (NULL);
649 	}
650 
651 	flags |= dtp->dt_dflags;
652 
653 	if (dof_hdr(dtp, pgp->dp_dofversion, &h) != 0)
654 		return (NULL);
655 
656 	if (dt_dof_reset(dtp, pgp) != 0)
657 		return (NULL);
658 
659 	/*
660 	 * Iterate through the statement list computing the maximum number of
661 	 * actions and the maximum format string for allocating local buffers.
662 	 */
663 	for (last = NULL, stp = dt_list_next(&pgp->dp_stmts);
664 	    stp != NULL; stp = dt_list_next(stp), last = edp) {
665 
666 		dtrace_stmtdesc_t *sdp = stp->ds_desc;
667 		dtrace_actdesc_t *ap = sdp->dtsd_action;
668 
669 		if (sdp->dtsd_fmtdata != NULL) {
670 			i = dtrace_printf_format(dtp,
671 			    sdp->dtsd_fmtdata, NULL, 0);
672 			maxfmt = MAX(maxfmt, i);
673 		}
674 
675 		if ((edp = sdp->dtsd_ecbdesc) == last)
676 			continue; /* same ecb as previous statement */
677 
678 		for (i = 0, ap = edp->dted_action; ap; ap = ap->dtad_next)
679 			i++;
680 
681 		maxacts = MAX(maxacts, i);
682 	}
683 
684 	dofa = alloca(sizeof (dof_actdesc_t) * maxacts);
685 	fmt = alloca(maxfmt + 1);
686 
687 	ddo->ddo_strsec = dof_add_lsect(ddo, NULL, DOF_SECT_STRTAB, 1, 0, 0, 0);
688 	(void) dof_add_string(ddo, "");
689 
690 	/*
691 	 * If there are references to dynamic translators in the program, add
692 	 * an imported translator table entry for each referenced translator.
693 	 */
694 	if (pgp->dp_xrefslen != 0) {
695 		for (dxp = dt_list_next(&dtp->dt_xlators);
696 		    dxp != NULL; dxp = dt_list_next(dxp)) {
697 			if (dxp->dx_id < pgp->dp_xrefslen &&
698 			    pgp->dp_xrefs[dxp->dx_id] != NULL)
699 				dof_add_translator(ddo, dxp, DOF_SECT_XLIMPORT);
700 		}
701 	}
702 
703 	/*
704 	 * Now iterate through the statement list, creating the DOF section
705 	 * headers and data for each one and adding them to our buffers.
706 	 */
707 	for (last = NULL, stp = dt_list_next(&pgp->dp_stmts);
708 	    stp != NULL; stp = dt_list_next(stp), last = edp) {
709 
710 		dof_secidx_t probesec = DOF_SECIDX_NONE;
711 		dof_secidx_t prdsec = DOF_SECIDX_NONE;
712 		dof_secidx_t actsec = DOF_SECIDX_NONE;
713 
714 		const dt_stmt_t *next = stp;
715 		dtrace_stmtdesc_t *sdp = stp->ds_desc;
716 		dof_stridx_t strndx = 0;
717 		dof_probedesc_t dofp;
718 		dof_ecbdesc_t dofe;
719 		uint_t i;
720 
721 		if ((edp = stp->ds_desc->dtsd_ecbdesc) == last)
722 			continue; /* same ecb as previous statement */
723 
724 		pdp = &edp->dted_probe;
725 
726 		/*
727 		 * Add a DOF_SECT_PROBEDESC for the ECB's probe description,
728 		 * and copy the probe description strings into the string table.
729 		 */
730 		dofp.dofp_strtab = ddo->ddo_strsec;
731 		dofp.dofp_provider = dof_add_string(ddo, pdp->dtpd_provider);
732 		dofp.dofp_mod = dof_add_string(ddo, pdp->dtpd_mod);
733 		dofp.dofp_func = dof_add_string(ddo, pdp->dtpd_func);
734 		dofp.dofp_name = dof_add_string(ddo, pdp->dtpd_name);
735 		dofp.dofp_id = pdp->dtpd_id;
736 
737 		probesec = dof_add_lsect(ddo, &dofp, DOF_SECT_PROBEDESC,
738 		    sizeof (dof_secidx_t), 0,
739 		    sizeof (dof_probedesc_t), sizeof (dof_probedesc_t));
740 
741 		/*
742 		 * If there is a predicate DIFO associated with the ecbdesc,
743 		 * write out the DIFO sections and save the DIFO section index.
744 		 */
745 		if (edp->dted_pred.dtpdd_difo != NULL)
746 			prdsec = dof_add_difo(ddo, edp->dted_pred.dtpdd_difo);
747 
748 		/*
749 		 * Now iterate through the action list generating DIFOs as
750 		 * referenced therein and adding action descriptions to 'dofa'.
751 		 */
752 		for (i = 0, ap = edp->dted_action;
753 		    ap != NULL; ap = ap->dtad_next, i++) {
754 
755 			if (ap->dtad_difo != NULL) {
756 				dofa[i].dofa_difo =
757 				    dof_add_difo(ddo, ap->dtad_difo);
758 			} else
759 				dofa[i].dofa_difo = DOF_SECIDX_NONE;
760 
761 			/*
762 			 * If the first action in a statement has string data,
763 			 * add the string to the global string table.  This can
764 			 * be due either to a printf() format string
765 			 * (dtsd_fmtdata) or a print() type string
766 			 * (dtsd_strdata).
767 			 */
768 			if (sdp != NULL && ap == sdp->dtsd_action) {
769 				if (sdp->dtsd_fmtdata != NULL) {
770 					(void) dtrace_printf_format(dtp,
771 					    sdp->dtsd_fmtdata, fmt, maxfmt + 1);
772 					strndx = dof_add_string(ddo, fmt);
773 				} else if (sdp->dtsd_strdata != NULL) {
774 					strndx = dof_add_string(ddo,
775 					    sdp->dtsd_strdata);
776 				} else {
777 					strndx = 0; /* use dtad_arg instead */
778 				}
779 
780 				if ((next = dt_list_next(next)) != NULL)
781 					sdp = next->ds_desc;
782 				else
783 					sdp = NULL;
784 			}
785 
786 			if (strndx != 0) {
787 				dofa[i].dofa_arg = strndx;
788 				dofa[i].dofa_strtab = ddo->ddo_strsec;
789 			} else {
790 				dofa[i].dofa_arg = ap->dtad_arg;
791 				dofa[i].dofa_strtab = DOF_SECIDX_NONE;
792 			}
793 
794 			dofa[i].dofa_kind = ap->dtad_kind;
795 			dofa[i].dofa_ntuple = ap->dtad_ntuple;
796 			dofa[i].dofa_uarg = ap->dtad_uarg;
797 		}
798 
799 		if (i > 0) {
800 			actsec = dof_add_lsect(ddo, dofa, DOF_SECT_ACTDESC,
801 			    sizeof (uint64_t), 0, sizeof (dof_actdesc_t),
802 			    sizeof (dof_actdesc_t) * i);
803 		}
804 
805 		/*
806 		 * Now finally, add the DOF_SECT_ECBDESC referencing all the
807 		 * previously created sub-sections.
808 		 */
809 		dofe.dofe_probes = probesec;
810 		dofe.dofe_pred = prdsec;
811 		dofe.dofe_actions = actsec;
812 		dofe.dofe_pad = 0;
813 		dofe.dofe_uarg = edp->dted_uarg;
814 
815 		(void) dof_add_lsect(ddo, &dofe, DOF_SECT_ECBDESC,
816 		    sizeof (uint64_t), 0, 0, sizeof (dof_ecbdesc_t));
817 	}
818 
819 	/*
820 	 * If any providers are user-defined, output DOF sections corresponding
821 	 * to the providers and the probes and arguments that they define.
822 	 */
823 	if (flags & DTRACE_D_PROBES) {
824 		for (pvp = dt_list_next(&dtp->dt_provlist);
825 		    pvp != NULL; pvp = dt_list_next(pvp)) {
826 			if (dof_add_provider(ddo, pvp) != 0)
827 				return (NULL);
828 		}
829 	}
830 
831 	/*
832 	 * If we're not stripping unloadable sections, generate compiler
833 	 * comments and any other unloadable miscellany.
834 	 */
835 	if (!(flags & DTRACE_D_STRIP)) {
836 		(void) dof_add_usect(ddo, _dtrace_version, DOF_SECT_COMMENTS,
837 		    sizeof (char), 0, 0, strlen(_dtrace_version) + 1);
838 		(void) dof_add_usect(ddo, &dtp->dt_uts, DOF_SECT_UTSNAME,
839 		    sizeof (char), 0, 0, sizeof (struct utsname));
840 	}
841 
842 	/*
843 	 * Compute and fill in the appropriate values for the dof_hdr_t's
844 	 * dofh_secnum, dofh_loadsz, and dofh_filez values.
845 	 */
846 	h.dofh_secnum = ddo->ddo_nsecs;
847 	ssize = sizeof (h) + dt_buf_len(&ddo->ddo_secs);
848 
849 	h.dofh_loadsz = ssize +
850 	    dt_buf_len(&ddo->ddo_ldata) +
851 	    dt_buf_len(&ddo->ddo_strs);
852 
853 	if (dt_buf_len(&ddo->ddo_udata) != 0) {
854 		lsize = roundup(h.dofh_loadsz, sizeof (uint64_t));
855 		h.dofh_filesz = lsize + dt_buf_len(&ddo->ddo_udata);
856 	} else {
857 		lsize = h.dofh_loadsz;
858 		h.dofh_filesz = lsize;
859 	}
860 
861 	/*
862 	 * Set the global DOF_SECT_STRTAB's offset to be after the header,
863 	 * section headers, and other loadable data.  Since we're going to
864 	 * iterate over the buffer data directly, we must check for errors.
865 	 */
866 	if ((i = dt_buf_error(&ddo->ddo_secs)) != 0) {
867 		(void) dt_set_errno(dtp, i);
868 		return (NULL);
869 	}
870 
871 	sp = dt_buf_ptr(&ddo->ddo_secs);
872 	assert(sp[ddo->ddo_strsec].dofs_type == DOF_SECT_STRTAB);
873 	assert(ssize == sizeof (h) + sizeof (dof_sec_t) * ddo->ddo_nsecs);
874 
875 	sp[ddo->ddo_strsec].dofs_offset = ssize + dt_buf_len(&ddo->ddo_ldata);
876 	sp[ddo->ddo_strsec].dofs_size = dt_buf_len(&ddo->ddo_strs);
877 
878 	/*
879 	 * Now relocate all the other section headers by adding the appropriate
880 	 * delta to their respective dofs_offset values.
881 	 */
882 	for (i = 0; i < ddo->ddo_nsecs; i++, sp++) {
883 		if (i == ddo->ddo_strsec)
884 			continue; /* already relocated above */
885 
886 		if (sp->dofs_flags & DOF_SECF_LOAD)
887 			sp->dofs_offset += ssize;
888 		else
889 			sp->dofs_offset += lsize;
890 	}
891 
892 	/*
893 	 * Finally, assemble the complete in-memory DOF buffer by writing the
894 	 * header and then concatenating all our buffers.  dt_buf_concat() will
895 	 * propagate any errors and cause dt_buf_claim() to return NULL.
896 	 */
897 	dt_buf_create(dtp, &dof, "dof", h.dofh_filesz);
898 
899 	dt_buf_write(dtp, &dof, &h, sizeof (h), sizeof (uint64_t));
900 	dt_buf_concat(dtp, &dof, &ddo->ddo_secs, sizeof (uint64_t));
901 	dt_buf_concat(dtp, &dof, &ddo->ddo_ldata, sizeof (uint64_t));
902 	dt_buf_concat(dtp, &dof, &ddo->ddo_strs, sizeof (char));
903 	dt_buf_concat(dtp, &dof, &ddo->ddo_udata, sizeof (uint64_t));
904 
905 	return (dt_buf_claim(dtp, &dof));
906 }
907 
908 void
909 dtrace_dof_destroy(dtrace_hdl_t *dtp, void *dof)
910 {
911 	dt_free(dtp, dof);
912 }
913 
914 void *
915 dtrace_getopt_dof(dtrace_hdl_t *dtp)
916 {
917 	dof_hdr_t *dof;
918 	dof_sec_t *sec;
919 	dof_optdesc_t *dofo;
920 	int i, nopts = 0, len = sizeof (dof_hdr_t) +
921 	    roundup(sizeof (dof_sec_t), sizeof (uint64_t));
922 
923 	for (i = 0; i < DTRACEOPT_MAX; i++) {
924 		if (dtp->dt_options[i] != DTRACEOPT_UNSET)
925 			nopts++;
926 	}
927 
928 	len += sizeof (dof_optdesc_t) * nopts;
929 
930 	if ((dof = dt_zalloc(dtp, len)) == NULL ||
931 	    dof_hdr(dtp, DOF_VERSION, dof) != 0) {
932 		dt_free(dtp, dof);
933 		return (NULL);
934 	}
935 
936 	dof->dofh_secnum = 1;	/* only DOF_SECT_OPTDESC */
937 	dof->dofh_loadsz = len;
938 	dof->dofh_filesz = len;
939 
940 	/*
941 	 * Fill in the option section header...
942 	 */
943 	sec = (dof_sec_t *)((uintptr_t)dof + sizeof (dof_hdr_t));
944 	sec->dofs_type = DOF_SECT_OPTDESC;
945 	sec->dofs_align = sizeof (uint64_t);
946 	sec->dofs_flags = DOF_SECF_LOAD;
947 	sec->dofs_entsize = sizeof (dof_optdesc_t);
948 
949 	dofo = (dof_optdesc_t *)((uintptr_t)sec +
950 	    roundup(sizeof (dof_sec_t), sizeof (uint64_t)));
951 
952 	sec->dofs_offset = (uintptr_t)dofo - (uintptr_t)dof;
953 	sec->dofs_size = sizeof (dof_optdesc_t) * nopts;
954 
955 	for (i = 0; i < DTRACEOPT_MAX; i++) {
956 		if (dtp->dt_options[i] == DTRACEOPT_UNSET)
957 			continue;
958 
959 		dofo->dofo_option = i;
960 		dofo->dofo_strtab = DOF_SECIDX_NONE;
961 		dofo->dofo_value = dtp->dt_options[i];
962 		dofo++;
963 	}
964 
965 	return (dof);
966 }
967 
968 void *
969 dtrace_geterr_dof(dtrace_hdl_t *dtp)
970 {
971 	if (dtp->dt_errprog != NULL)
972 		return (dtrace_dof_create(dtp, dtp->dt_errprog, 0));
973 
974 	(void) dt_set_errno(dtp, EDT_BADERROR);
975 	return (NULL);
976 }
977