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