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 <sys/types.h>
32 #include <strings.h>
33 #include <stdlib.h>
34 #include <assert.h>
35
36 #include <dt_impl.h>
37 #include <dt_parser.h>
38 #include <dt_as.h>
39
40 void
41 dt_irlist_create(dt_irlist_t *dlp)
42 {
43 bzero(dlp, sizeof (dt_irlist_t));
44 dlp->dl_label = 1;
45 }
46
47 void
48 dt_irlist_destroy(dt_irlist_t *dlp)
49 {
50 dt_irnode_t *dip, *nip;
51
52 for (dip = dlp->dl_list; dip != NULL; dip = nip) {
53 nip = dip->di_next;
54 free(dip);
55 }
56 }
57
58 void
59 dt_irlist_append(dt_irlist_t *dlp, dt_irnode_t *dip)
60 {
61 if (dlp->dl_last != NULL)
62 dlp->dl_last->di_next = dip;
63 else
64 dlp->dl_list = dip;
65
66 dlp->dl_last = dip;
67
68 if (dip->di_label == DT_LBL_NONE || dip->di_instr != DIF_INSTR_NOP)
69 dlp->dl_len++; /* don't count forward refs in instr count */
70 }
71
72 uint_t
73 dt_irlist_label(dt_irlist_t *dlp)
74 {
75 return (dlp->dl_label++);
76 }
77
78 /*ARGSUSED*/
79 static int
80 dt_countvar(dt_idhash_t *dhp, dt_ident_t *idp, void *data)
81 {
82 size_t *np = data;
83
84 if (idp->di_flags & (DT_IDFLG_DIFR | DT_IDFLG_DIFW))
85 (*np)++; /* include variable in vartab */
86
87 return (0);
88 }
89
90 /*ARGSUSED*/
91 static int
92 dt_copyvar(dt_idhash_t *dhp, dt_ident_t *idp, void *data)
93 {
94 dt_pcb_t *pcb = data;
95 dtrace_difv_t *dvp;
96 ssize_t stroff;
97 dt_node_t dn;
98
99 if (!(idp->di_flags & (DT_IDFLG_DIFR | DT_IDFLG_DIFW)))
100 return (0); /* omit variable from vartab */
101
102 dvp = &pcb->pcb_difo->dtdo_vartab[pcb->pcb_asvidx++];
103 stroff = dt_strtab_insert(pcb->pcb_strtab, idp->di_name);
104
105 if (stroff == -1L)
106 longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
107 if (stroff > DIF_STROFF_MAX)
108 longjmp(pcb->pcb_jmpbuf, EDT_STR2BIG);
109
110 dvp->dtdv_name = (uint_t)stroff;
111 dvp->dtdv_id = idp->di_id;
112 dvp->dtdv_flags = 0;
113
114 dvp->dtdv_kind = (idp->di_kind == DT_IDENT_ARRAY) ?
115 DIFV_KIND_ARRAY : DIFV_KIND_SCALAR;
116
117 if (idp->di_flags & DT_IDFLG_LOCAL)
118 dvp->dtdv_scope = DIFV_SCOPE_LOCAL;
119 else if (idp->di_flags & DT_IDFLG_TLS)
120 dvp->dtdv_scope = DIFV_SCOPE_THREAD;
121 else
122 dvp->dtdv_scope = DIFV_SCOPE_GLOBAL;
123
124 if (idp->di_flags & DT_IDFLG_DIFR)
125 dvp->dtdv_flags |= DIFV_F_REF;
126 if (idp->di_flags & DT_IDFLG_DIFW)
127 dvp->dtdv_flags |= DIFV_F_MOD;
128
129 bzero(&dn, sizeof (dn));
130 dt_node_type_assign(&dn, idp->di_ctfp, idp->di_type, B_FALSE);
131 dt_node_diftype(pcb->pcb_hdl, &dn, &dvp->dtdv_type);
132
133 idp->di_flags &= ~(DT_IDFLG_DIFR | DT_IDFLG_DIFW);
134 return (0);
135 }
136
137 static ssize_t
138 dt_copystr(const char *s, size_t n, size_t off, dt_pcb_t *pcb)
139 {
140 bcopy(s, pcb->pcb_difo->dtdo_strtab + off, n);
141 return (n);
142 }
143
144 /*
145 * Rewrite the xlate/xlarg instruction at dtdo_buf[i] so that the instruction's
146 * xltab index reflects the offset 'xi' of the assigned dtdo_xlmtab[] location.
147 * We track the cumulative references to translators and members in the pcb's
148 * pcb_asxrefs[] array, a two-dimensional array of bitmaps indexed by the
149 * global translator id and then by the corresponding translator member id.
150 */
151 static void
152 dt_as_xlate(dt_pcb_t *pcb, dtrace_difo_t *dp,
153 uint_t i, uint_t xi, dt_node_t *dnp)
154 {
155 dtrace_hdl_t *dtp = pcb->pcb_hdl;
156 dt_xlator_t *dxp = dnp->dn_membexpr->dn_xlator;
157
158 assert(i < dp->dtdo_len);
159 assert(xi < dp->dtdo_xlmlen);
160
161 assert(dnp->dn_kind == DT_NODE_MEMBER);
162 assert(dnp->dn_membexpr->dn_kind == DT_NODE_XLATOR);
163
164 assert(dxp->dx_id < dtp->dt_xlatorid);
165 assert(dnp->dn_membid < dxp->dx_nmembers);
166
167 if (pcb->pcb_asxrefs == NULL) {
168 pcb->pcb_asxreflen = dtp->dt_xlatorid;
169 pcb->pcb_asxrefs =
170 dt_zalloc(dtp, sizeof (ulong_t *) * pcb->pcb_asxreflen);
171 if (pcb->pcb_asxrefs == NULL)
172 longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
173 }
174
175 if (pcb->pcb_asxrefs[dxp->dx_id] == NULL) {
176 pcb->pcb_asxrefs[dxp->dx_id] =
177 dt_zalloc(dtp, BT_SIZEOFMAP(dxp->dx_nmembers));
178 if (pcb->pcb_asxrefs[dxp->dx_id] == NULL)
179 longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
180 }
181
182 dp->dtdo_buf[i] = DIF_INSTR_XLATE(
183 DIF_INSTR_OP(dp->dtdo_buf[i]), xi, DIF_INSTR_RD(dp->dtdo_buf[i]));
184
185 BT_SET(pcb->pcb_asxrefs[dxp->dx_id], dnp->dn_membid);
186 dp->dtdo_xlmtab[xi] = dnp;
187 }
188
189 static void
190 dt_as_undef(const dt_ident_t *idp, uint_t offset)
191 {
192 const char *kind, *mark = (idp->di_flags & DT_IDFLG_USER) ? "``" : "`";
193 const dtrace_syminfo_t *dts = idp->di_data;
194
195 if (idp->di_flags & DT_IDFLG_USER)
196 kind = "user";
197 else if (idp->di_flags & DT_IDFLG_PRIM)
198 kind = "primary kernel";
199 else
200 kind = "loadable kernel";
201
202 yylineno = idp->di_lineno;
203
204 xyerror(D_ASRELO, "relocation remains against %s symbol %s%s%s (offset "
205 "0x%x)\n", kind, dts->dts_object, mark, dts->dts_name, offset);
206 }
207
208 dtrace_difo_t *
209 dt_as(dt_pcb_t *pcb)
210 {
211 dtrace_hdl_t *dtp = pcb->pcb_hdl;
212 dt_irlist_t *dlp = &pcb->pcb_ir;
213 uint_t *labels = NULL;
214 dt_irnode_t *dip;
215 dtrace_difo_t *dp;
216 dt_ident_t *idp;
217
218 size_t n = 0;
219 uint_t i;
220
221 uint_t kmask, kbits, umask, ubits;
222 uint_t krel = 0, urel = 0, xlrefs = 0;
223
224 /*
225 * Select bitmasks based upon the desired symbol linking policy. We
226 * test (di_extern->di_flags & xmask) == xbits to determine if the
227 * symbol should have a relocation entry generated in the loop below.
228 *
229 * DT_LINK_KERNEL = kernel symbols static, user symbols dynamic
230 * DT_LINK_PRIMARY = primary kernel symbols static, others dynamic
231 * DT_LINK_DYNAMIC = all symbols dynamic
232 * DT_LINK_STATIC = all symbols static
233 *
234 * By 'static' we mean that we use the symbol's value at compile-time
235 * in the final DIF. By 'dynamic' we mean that we create a relocation
236 * table entry for the symbol's value so it can be relocated later.
237 */
238 switch (dtp->dt_linkmode) {
239 case DT_LINK_KERNEL:
240 kmask = 0;
241 kbits = -1u;
242 umask = DT_IDFLG_USER;
243 ubits = DT_IDFLG_USER;
244 break;
245 case DT_LINK_PRIMARY:
246 kmask = DT_IDFLG_USER | DT_IDFLG_PRIM;
247 kbits = 0;
248 umask = DT_IDFLG_USER;
249 ubits = DT_IDFLG_USER;
250 break;
251 case DT_LINK_DYNAMIC:
252 kmask = DT_IDFLG_USER;
253 kbits = 0;
254 umask = DT_IDFLG_USER;
255 ubits = DT_IDFLG_USER;
256 break;
257 case DT_LINK_STATIC:
258 kmask = umask = 0;
259 kbits = ubits = -1u;
260 break;
261 default:
262 xyerror(D_UNKNOWN, "internal error -- invalid link mode %u\n",
263 dtp->dt_linkmode);
264 }
265
266 assert(pcb->pcb_difo == NULL);
267 pcb->pcb_difo = dt_zalloc(dtp, sizeof (dtrace_difo_t));
268
269 if ((dp = pcb->pcb_difo) == NULL)
270 longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
271
272 dp->dtdo_buf = dt_alloc(dtp, sizeof (dif_instr_t) * dlp->dl_len);
273
274 if (dp->dtdo_buf == NULL)
275 longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
276
277 if ((labels = dt_alloc(dtp, sizeof (uint_t) * dlp->dl_label)) == NULL)
278 longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
279
280 /*
281 * Make an initial pass through the instruction list, filling in the
282 * instruction buffer with valid instructions and skipping labeled nops.
283 * While doing this, we also fill in our labels[] translation table
284 * and we count up the number of relocation table entries we will need.
285 */
286 for (i = 0, dip = dlp->dl_list; dip != NULL; dip = dip->di_next) {
287 if (dip->di_label != DT_LBL_NONE)
288 labels[dip->di_label] = i;
289
290 if (dip->di_label == DT_LBL_NONE ||
291 dip->di_instr != DIF_INSTR_NOP)
292 dp->dtdo_buf[i++] = dip->di_instr;
293
294 if (dip->di_extern == NULL)
295 continue; /* no external references needed */
296
297 switch (DIF_INSTR_OP(dip->di_instr)) {
298 case DIF_OP_SETX:
299 idp = dip->di_extern;
300 if ((idp->di_flags & kmask) == kbits)
301 krel++;
302 else if ((idp->di_flags & umask) == ubits)
303 urel++;
304 break;
305 case DIF_OP_XLATE:
306 case DIF_OP_XLARG:
307 xlrefs++;
308 break;
309 default:
310 xyerror(D_UNKNOWN, "unexpected assembler relocation "
311 "for opcode 0x%x\n", DIF_INSTR_OP(dip->di_instr));
312 }
313 }
314
315 assert(i == dlp->dl_len);
316 dp->dtdo_len = dlp->dl_len;
317
318 /*
319 * Make a second pass through the instructions, relocating each branch
320 * label to the index of the final instruction in the buffer and noting
321 * any other instruction-specific DIFO flags such as dtdo_destructive.
322 */
323 for (i = 0; i < dp->dtdo_len; i++) {
324 dif_instr_t instr = dp->dtdo_buf[i];
325 uint_t op = DIF_INSTR_OP(instr);
326
327 if (op == DIF_OP_CALL) {
328 if (DIF_INSTR_SUBR(instr) == DIF_SUBR_COPYOUT ||
329 DIF_INSTR_SUBR(instr) == DIF_SUBR_COPYOUTSTR)
330 dp->dtdo_destructive = 1;
331 continue;
332 }
333
334 if (op >= DIF_OP_BA && op <= DIF_OP_BLEU) {
335 assert(DIF_INSTR_LABEL(instr) < dlp->dl_label);
336 dp->dtdo_buf[i] = DIF_INSTR_BRANCH(op,
337 labels[DIF_INSTR_LABEL(instr)]);
338 }
339 }
340
341 dt_free(dtp, labels);
342 pcb->pcb_asvidx = 0;
343
344 /*
345 * Allocate memory for the appropriate number of variable records and
346 * then fill in each variable record. As we populate the variable
347 * table we insert the corresponding variable names into the strtab.
348 */
349 (void) dt_idhash_iter(dtp->dt_tls, dt_countvar, &n);
350 (void) dt_idhash_iter(dtp->dt_globals, dt_countvar, &n);
351 (void) dt_idhash_iter(pcb->pcb_locals, dt_countvar, &n);
352
353 if (n != 0) {
354 dp->dtdo_vartab = dt_alloc(dtp, n * sizeof (dtrace_difv_t));
355 dp->dtdo_varlen = (uint32_t)n;
356
357 if (dp->dtdo_vartab == NULL)
358 longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
359
360 (void) dt_idhash_iter(dtp->dt_tls, dt_copyvar, pcb);
361 (void) dt_idhash_iter(dtp->dt_globals, dt_copyvar, pcb);
362 (void) dt_idhash_iter(pcb->pcb_locals, dt_copyvar, pcb);
363 }
364
365 /*
366 * Allocate memory for the appropriate number of relocation table
367 * entries based upon our kernel and user counts from the first pass.
368 */
369 if (krel != 0) {
370 dp->dtdo_kreltab = dt_alloc(dtp,
371 krel * sizeof (dof_relodesc_t));
372 dp->dtdo_krelen = krel;
373
374 if (dp->dtdo_kreltab == NULL)
375 longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
376 }
377
378 if (urel != 0) {
379 dp->dtdo_ureltab = dt_alloc(dtp,
380 urel * sizeof (dof_relodesc_t));
381 dp->dtdo_urelen = urel;
382
383 if (dp->dtdo_ureltab == NULL)
384 longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
385 }
386
387 if (xlrefs != 0) {
388 dp->dtdo_xlmtab = dt_zalloc(dtp, sizeof (dt_node_t *) * xlrefs);
389 dp->dtdo_xlmlen = xlrefs;
390
391 if (dp->dtdo_xlmtab == NULL)
392 longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
393 }
394
395 /*
396 * If any relocations are needed, make another pass through the
397 * instruction list and fill in the relocation table entries.
398 */
399 if (krel + urel + xlrefs != 0) {
400 uint_t knodef = pcb->pcb_cflags & DTRACE_C_KNODEF;
401 uint_t unodef = pcb->pcb_cflags & DTRACE_C_UNODEF;
402
403 dof_relodesc_t *krp = dp->dtdo_kreltab;
404 dof_relodesc_t *urp = dp->dtdo_ureltab;
405 dt_node_t **xlp = dp->dtdo_xlmtab;
406
407 i = 0; /* dtdo_buf[] index */
408
409 for (dip = dlp->dl_list; dip != NULL; dip = dip->di_next) {
410 dof_relodesc_t *rp;
411 ssize_t soff;
412 uint_t nodef;
413
414 if (dip->di_label != DT_LBL_NONE &&
415 dip->di_instr == DIF_INSTR_NOP)
416 continue; /* skip label declarations */
417
418 i++; /* advance dtdo_buf[] index */
419
420 if (DIF_INSTR_OP(dip->di_instr) == DIF_OP_XLATE ||
421 DIF_INSTR_OP(dip->di_instr) == DIF_OP_XLARG) {
422 assert(dp->dtdo_buf[i - 1] == dip->di_instr);
423 dt_as_xlate(pcb, dp, i - 1, (uint_t)
424 (xlp++ - dp->dtdo_xlmtab), dip->di_extern);
425 continue;
426 }
427
428 if ((idp = dip->di_extern) == NULL)
429 continue; /* no relocation entry needed */
430
431 if ((idp->di_flags & kmask) == kbits) {
432 nodef = knodef;
433 rp = krp++;
434 } else if ((idp->di_flags & umask) == ubits) {
435 nodef = unodef;
436 rp = urp++;
437 } else
438 continue;
439
440 if (!nodef)
441 dt_as_undef(idp, i);
442
443 assert(DIF_INSTR_OP(dip->di_instr) == DIF_OP_SETX);
444 soff = dt_strtab_insert(pcb->pcb_strtab, idp->di_name);
445
446 if (soff == -1L)
447 longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
448 if (soff > DIF_STROFF_MAX)
449 longjmp(pcb->pcb_jmpbuf, EDT_STR2BIG);
450
451 rp->dofr_name = (dof_stridx_t)soff;
452 rp->dofr_type = DOF_RELO_SETX;
453 rp->dofr_offset = DIF_INSTR_INTEGER(dip->di_instr) *
454 sizeof (uint64_t);
455 rp->dofr_data = 0;
456 }
457
458 assert(krp == dp->dtdo_kreltab + dp->dtdo_krelen);
459 assert(urp == dp->dtdo_ureltab + dp->dtdo_urelen);
460 assert(xlp == dp->dtdo_xlmtab + dp->dtdo_xlmlen);
461 assert(i == dp->dtdo_len);
462 }
463
464 /*
465 * Allocate memory for the compiled string table and then copy the
466 * chunks from the string table into the final string buffer.
467 */
468 if ((n = dt_strtab_size(pcb->pcb_strtab)) != 0) {
469 if ((dp->dtdo_strtab = dt_alloc(dtp, n)) == NULL)
470 longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
471
472 (void) dt_strtab_write(pcb->pcb_strtab,
473 (dt_strtab_write_f *)dt_copystr, pcb);
474 dp->dtdo_strlen = (uint32_t)n;
475 }
476
477 /*
478 * Allocate memory for the compiled integer table and then copy the
479 * integer constants from the table into the final integer buffer.
480 */
481 if ((n = dt_inttab_size(pcb->pcb_inttab)) != 0) {
482 if ((dp->dtdo_inttab = dt_alloc(dtp,
483 n * sizeof (uint64_t))) == NULL)
484 longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);
485
486 dt_inttab_write(pcb->pcb_inttab, dp->dtdo_inttab);
487 dp->dtdo_intlen = (uint32_t)n;
488 }
489
490 /*
491 * Fill in the DIFO return type from the type associated with the
492 * node saved in pcb_dret, and then clear pcb_difo and pcb_dret
493 * now that the assembler has completed successfully.
494 */
495 dt_node_diftype(dtp, pcb->pcb_dret, &dp->dtdo_rtype);
496 pcb->pcb_difo = NULL;
497 pcb->pcb_dret = NULL;
498
499 if (pcb->pcb_cflags & DTRACE_C_DIFV)
500 dt_dis(dp, stderr);
501
502 return (dp);
503 }