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 2005 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26 /*
27 * Copyright (c) 2013 by Delphix. All rights reserved.
28 * Copyright (c) 2013 Joyent, Inc. All rights reserved.
29 */
30
31 #include <strings.h>
32 #include <assert.h>
33
34 #include <dt_xlator.h>
35 #include <dt_parser.h>
36 #include <dt_grammar.h>
37 #include <dt_module.h>
38 #include <dt_impl.h>
39
40 /*
41 * Create a member node corresponding to one of the output members of a dynamic
42 * translator. We set the member's dn_membexpr to a DT_NODE_XLATOR node that
43 * has dn_op set to DT_TOK_XLATE and refers back to the translator itself. The
44 * code generator will then use this as the indicator for dynamic translation.
45 */
46 /*ARGSUSED*/
47 static int
48 dt_xlator_create_member(const char *name, ctf_id_t type, ulong_t off, void *arg)
49 {
50 dt_xlator_t *dxp = arg;
51 dtrace_hdl_t *dtp = dxp->dx_hdl;
52 dt_node_t *enp, *mnp;
53 ctf_file_t *ctfp;
54
55 if ((enp = dt_node_xalloc(dtp, DT_NODE_XLATOR)) == NULL)
56 return (dt_set_errno(dtp, EDT_NOMEM));
57
58 enp->dn_link = dxp->dx_nodes;
59 dxp->dx_nodes = enp;
60
61 if ((mnp = dt_node_xalloc(dtp, DT_NODE_MEMBER)) == NULL)
62 return (dt_set_errno(dtp, EDT_NOMEM));
63
64 mnp->dn_link = dxp->dx_nodes;
65 dxp->dx_nodes = mnp;
66
67 /*
68 * For the member expression, we use a DT_NODE_XLATOR/TOK_XLATE whose
69 * xlator refers back to the translator and whose dn_xmember refers to
70 * the current member. These refs will be used by dt_cg.c and dt_as.c.
71 */
72 enp->dn_op = DT_TOK_XLATE;
73 enp->dn_xlator = dxp;
74 enp->dn_xmember = mnp;
75 /*
76 * XXX: Is it ok for the CTF of the type to not be from the dst ctf?
77 *
78 * I suspect it's actually unnecessary, but I'm also unclear on
79 * dynamic translators
80 */
81 dt_resolve_forward_decl(&ctfp, &type);
82 dt_node_type_assign(enp, ctfp, type, B_FALSE);
83
84 /*
85 * For the member itself, we use a DT_NODE_MEMBER as usual with the
86 * appropriate name, output type, and member expression set to 'enp'.
87 */
88 if (dxp->dx_members != NULL) {
89 assert(enp->dn_link->dn_kind == DT_NODE_MEMBER);
90 enp->dn_link->dn_list = mnp;
91 } else
92 dxp->dx_members = mnp;
93
94 mnp->dn_membname = strdup(name);
95 mnp->dn_membexpr = enp;
96 dt_node_type_assign(mnp, dxp->dx_dst_ctfp, type, B_FALSE);
97
98 if (mnp->dn_membname == NULL)
99 return (dt_set_errno(dtp, EDT_NOMEM));
100
101 return (0);
102 }
103
104 dt_xlator_t *
105 dt_xlator_create(dtrace_hdl_t *dtp,
106 const dtrace_typeinfo_t *src, const dtrace_typeinfo_t *dst,
107 const char *name, dt_node_t *members, dt_node_t *nodes)
108 {
109 dt_xlator_t *dxp = dt_zalloc(dtp, sizeof (dt_xlator_t));
110 dtrace_typeinfo_t ptr = *dst;
111 dt_xlator_t **map;
112 dt_node_t *dnp;
113 uint_t kind;
114
115 if (dxp == NULL)
116 return (NULL);
117
118 dxp->dx_hdl = dtp;
119 dxp->dx_id = dtp->dt_xlatorid++;
120 dxp->dx_gen = dtp->dt_gen;
121 dxp->dx_arg = -1;
122
123 if ((map = dt_alloc(dtp, sizeof (void *) * (dxp->dx_id + 1))) == NULL) {
124 dt_free(dtp, dxp);
125 return (NULL);
126 }
127
128 dt_list_append(&dtp->dt_xlators, dxp);
129 bcopy(dtp->dt_xlatormap, map, sizeof (void *) * dxp->dx_id);
130 dt_free(dtp, dtp->dt_xlatormap);
131 dtp->dt_xlatormap = map;
132 dtp->dt_xlatormap[dxp->dx_id] = dxp;
133
134 if (dt_type_pointer(&ptr) == -1) {
135 ptr.dtt_ctfp = NULL;
136 ptr.dtt_type = CTF_ERR;
137 }
138
139 dxp->dx_ident = dt_ident_create(name ? name : "T",
140 DT_IDENT_SCALAR, DT_IDFLG_REF | DT_IDFLG_ORPHAN, 0,
141 _dtrace_defattr, 0, &dt_idops_thaw, NULL, dtp->dt_gen);
142
143 if (dxp->dx_ident == NULL)
144 goto err; /* no memory for identifier */
145
146 dxp->dx_ident->di_ctfp = src->dtt_ctfp;
147 dxp->dx_ident->di_type = src->dtt_type;
148
149 /*
150 * If an input parameter name is given, this is a static translator
151 * definition: create an idhash and identifier for the parameter.
152 */
153 if (name != NULL) {
154 dxp->dx_locals = dt_idhash_create("xlparams", NULL, 0, 0);
155
156 if (dxp->dx_locals == NULL)
157 goto err; /* no memory for identifier hash */
158
159 dt_idhash_xinsert(dxp->dx_locals, dxp->dx_ident);
160 }
161
162 dxp->dx_souid.di_name = "translator";
163 dxp->dx_souid.di_kind = DT_IDENT_XLSOU;
164 dxp->dx_souid.di_flags = DT_IDFLG_REF;
165 dxp->dx_souid.di_id = dxp->dx_id;
166 dxp->dx_souid.di_attr = _dtrace_defattr;
167 dxp->dx_souid.di_ops = &dt_idops_thaw;
168 dxp->dx_souid.di_data = dxp;
169 dxp->dx_souid.di_ctfp = dst->dtt_ctfp;
170 dxp->dx_souid.di_type = dst->dtt_type;
171 dxp->dx_souid.di_gen = dtp->dt_gen;
172
173 dxp->dx_ptrid.di_name = "translator";
174 dxp->dx_ptrid.di_kind = DT_IDENT_XLPTR;
175 dxp->dx_ptrid.di_flags = DT_IDFLG_REF;
176 dxp->dx_ptrid.di_id = dxp->dx_id;
177 dxp->dx_ptrid.di_attr = _dtrace_defattr;
178 dxp->dx_ptrid.di_ops = &dt_idops_thaw;
179 dxp->dx_ptrid.di_data = dxp;
180 dxp->dx_ptrid.di_ctfp = ptr.dtt_ctfp;
181 dxp->dx_ptrid.di_type = ptr.dtt_type;
182 dxp->dx_ptrid.di_gen = dtp->dt_gen;
183
184 /*
185 * If a deferred pragma is pending on the keyword "translator", run all
186 * the deferred pragmas on dx_souid and then copy results to dx_ptrid.
187 * See the code in dt_pragma.c for details on deferred ident pragmas.
188 */
189 if (dtp->dt_globals->dh_defer != NULL && yypcb->pcb_pragmas != NULL &&
190 dt_idhash_lookup(yypcb->pcb_pragmas, "translator") != NULL) {
191 dtp->dt_globals->dh_defer(dtp->dt_globals, &dxp->dx_souid);
192 dxp->dx_ptrid.di_attr = dxp->dx_souid.di_attr;
193 dxp->dx_ptrid.di_vers = dxp->dx_souid.di_vers;
194 }
195
196 dxp->dx_src_ctfp = src->dtt_ctfp;
197 dxp->dx_src_type = src->dtt_type;
198 dxp->dx_src_base = ctf_type_resolve(src->dtt_ctfp, src->dtt_type);
199
200 dxp->dx_dst_ctfp = dst->dtt_ctfp;
201 dxp->dx_dst_type = dst->dtt_type;
202 dxp->dx_dst_base = ctf_type_resolve(dst->dtt_ctfp, dst->dtt_type);
203
204 kind = ctf_type_kind(dst->dtt_ctfp, dxp->dx_dst_base);
205 assert(kind == CTF_K_STRUCT || kind == CTF_K_UNION);
206
207 /*
208 * If no input parameter is given, we're making a dynamic translator:
209 * create member nodes for every member of the output type. Otherwise
210 * retain the member and allocation node lists presented by the parser.
211 */
212 if (name == NULL) {
213 if (ctf_member_iter(dxp->dx_dst_ctfp, dxp->dx_dst_base,
214 dt_xlator_create_member, dxp) != 0)
215 goto err;
216 } else {
217 dxp->dx_members = members;
218 dxp->dx_nodes = nodes;
219 }
220
221 /*
222 * Assign member IDs to each member and allocate space for DIFOs
223 * if and when this translator is eventually compiled.
224 */
225 for (dnp = dxp->dx_members; dnp != NULL; dnp = dnp->dn_list) {
226 dnp->dn_membxlator = dxp;
227 dnp->dn_membid = dxp->dx_nmembers++;
228 }
229
230 dxp->dx_membdif = dt_zalloc(dtp,
231 sizeof (dtrace_difo_t *) * dxp->dx_nmembers);
232
233 if (dxp->dx_membdif == NULL) {
234 dxp->dx_nmembers = 0;
235 goto err;
236 }
237
238 return (dxp);
239
240 err:
241 dt_xlator_destroy(dtp, dxp);
242 return (NULL);
243 }
244
245 void
246 dt_xlator_destroy(dtrace_hdl_t *dtp, dt_xlator_t *dxp)
247 {
248 uint_t i;
249
250 dt_node_link_free(&dxp->dx_nodes);
251
252 if (dxp->dx_locals != NULL)
253 dt_idhash_destroy(dxp->dx_locals);
254 else if (dxp->dx_ident != NULL)
255 dt_ident_destroy(dxp->dx_ident);
256
257 for (i = 0; i < dxp->dx_nmembers; i++)
258 dt_difo_free(dtp, dxp->dx_membdif[i]);
259
260 dt_free(dtp, dxp->dx_membdif);
261 dt_list_delete(&dtp->dt_xlators, dxp);
262 dt_free(dtp, dxp);
263 }
264
265 dt_xlator_t *
266 dt_xlator_lookup(dtrace_hdl_t *dtp, dt_node_t *src, dt_node_t *dst, int flags)
267 {
268 ctf_file_t *src_ctfp = src->dn_ctfp;
269 ctf_id_t src_type = src->dn_type;
270 ctf_id_t src_base = ctf_type_resolve(src_ctfp, src_type);
271
272 ctf_file_t *dst_ctfp = dst->dn_ctfp;
273 ctf_id_t dst_type = dst->dn_type;
274 ctf_id_t dst_base = ctf_type_resolve(dst_ctfp, dst_type);
275 uint_t dst_kind = ctf_type_kind(dst_ctfp, dst_base);
276
277 int ptr = dst_kind == CTF_K_POINTER;
278 dtrace_typeinfo_t src_dtt, dst_dtt;
279 dt_node_t xn = { 0 };
280 dt_xlator_t *dxp = NULL;
281
282 if (src_base == CTF_ERR || dst_base == CTF_ERR)
283 return (NULL); /* fail if these are unresolvable types */
284
285 /*
286 * Translators are always defined using a struct or union type, so if
287 * we are attempting to translate to type "T *", we internally look
288 * for a translation to type "T" by following the pointer reference.
289 */
290 if (ptr) {
291 dst_type = ctf_type_reference(dst_ctfp, dst_type);
292 dst_base = ctf_type_resolve(dst_ctfp, dst_type);
293 dst_kind = ctf_type_kind(dst_ctfp, dst_base);
294 }
295
296 if (dst_kind != CTF_K_UNION && dst_kind != CTF_K_STRUCT)
297 return (NULL); /* fail if the output isn't a struct or union */
298
299 /*
300 * In order to find a matching translator, we iterate over the set of
301 * available translators in three passes. First, we look for a
302 * translation from the exact source type to the resolved destination.
303 * Second, we look for a translation from the resolved source type to
304 * the resolved destination. Third, we look for a translation from a
305 * compatible source type (using the same rules as parameter formals)
306 * to the resolved destination. If all passes fail, return NULL.
307 */
308 for (dxp = dt_list_next(&dtp->dt_xlators); dxp != NULL;
309 dxp = dt_list_next(dxp)) {
310 if (ctf_type_compat(dxp->dx_src_ctfp, dxp->dx_src_type,
311 src_ctfp, src_type) &&
312 ctf_type_compat(dxp->dx_dst_ctfp, dxp->dx_dst_base,
313 dst_ctfp, dst_base))
314 goto out;
315 }
316
317 if (flags & DT_XLATE_EXACT)
318 goto out; /* skip remaining passes if exact match required */
319
320 for (dxp = dt_list_next(&dtp->dt_xlators); dxp != NULL;
321 dxp = dt_list_next(dxp)) {
322 if (ctf_type_compat(dxp->dx_src_ctfp, dxp->dx_src_base,
323 src_ctfp, src_type) &&
324 ctf_type_compat(dxp->dx_dst_ctfp, dxp->dx_dst_base,
325 dst_ctfp, dst_base))
326 goto out;
327 }
328
329 for (dxp = dt_list_next(&dtp->dt_xlators); dxp != NULL;
330 dxp = dt_list_next(dxp)) {
331 dt_node_type_assign(&xn, dxp->dx_src_ctfp, dxp->dx_src_type,
332 B_FALSE);
333 if (ctf_type_compat(dxp->dx_dst_ctfp, dxp->dx_dst_base,
334 dst_ctfp, dst_base) && dt_node_is_argcompat(src, &xn))
335 goto out;
336 }
337
338 out:
339 if (ptr && dxp != NULL && dxp->dx_ptrid.di_type == CTF_ERR)
340 return (NULL); /* no translation available to pointer type */
341
342 if (dxp != NULL || !(flags & DT_XLATE_EXTERN) ||
343 dtp->dt_xlatemode == DT_XL_STATIC)
344 return (dxp); /* we succeeded or not allowed to extern */
345
346 /*
347 * If we get here, then we didn't find an existing translator, but the
348 * caller and xlatemode permit us to create an extern to a dynamic one.
349 */
350 src_dtt.dtt_object = dt_module_lookup_by_ctf(dtp, src_ctfp)->dm_name;
351 src_dtt.dtt_ctfp = src_ctfp;
352 src_dtt.dtt_type = src_type;
353
354 dst_dtt.dtt_object = dt_module_lookup_by_ctf(dtp, dst_ctfp)->dm_name;
355 dst_dtt.dtt_ctfp = dst_ctfp;
356 dst_dtt.dtt_type = dst_type;
357
358 return (dt_xlator_create(dtp, &src_dtt, &dst_dtt, NULL, NULL, NULL));
359 }
360
361 dt_xlator_t *
362 dt_xlator_lookup_id(dtrace_hdl_t *dtp, id_t id)
363 {
364 assert(id >= 0 && id < dtp->dt_xlatorid);
365 return (dtp->dt_xlatormap[id]);
366 }
367
368 dt_ident_t *
369 dt_xlator_ident(dt_xlator_t *dxp, ctf_file_t *ctfp, ctf_id_t type)
370 {
371 if (ctf_type_kind(ctfp, ctf_type_resolve(ctfp, type)) == CTF_K_POINTER)
372 return (&dxp->dx_ptrid);
373 else
374 return (&dxp->dx_souid);
375 }
376
377 dt_node_t *
378 dt_xlator_member(dt_xlator_t *dxp, const char *name)
379 {
380 dt_node_t *dnp;
381
382 for (dnp = dxp->dx_members; dnp != NULL; dnp = dnp->dn_list) {
383 if (strcmp(dnp->dn_membname, name) == 0)
384 return (dnp);
385 }
386
387 return (NULL);
388 }
389
390 int
391 dt_xlator_dynamic(const dt_xlator_t *dxp)
392 {
393 return (dxp->dx_locals == NULL);
394 }