1 /*
2 * Copyright (C) 2013 Huawei Ltd.
3 * Author: Jiang Liu <liuj97@gmail.com>
4 *
5 * Copyright (C) 2014-2016 Zi Shen Lim <zlim.lnx@gmail.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 */
19 #include <linux/bitops.h>
20 #include <linux/bug.h>
21 #include <linux/compiler.h>
22 #include <linux/kernel.h>
23 #include <linux/mm.h>
24 #include <linux/smp.h>
25 #include <linux/spinlock.h>
26 #include <linux/stop_machine.h>
27 #include <linux/types.h>
28 #include <linux/uaccess.h>
29
30 #include <asm/cacheflush.h>
31 #include <asm/debug-monitors.h>
32 #include <asm/fixmap.h>
33 #include <asm/opcodes.h>
34 #include <asm/insn.h>
35
36 #define AARCH64_INSN_SF_BIT BIT(31)
37 #define AARCH64_INSN_N_BIT BIT(22)
38
39 static int aarch64_insn_encoding_class[] = {
40 AARCH64_INSN_CLS_UNKNOWN,
41 AARCH64_INSN_CLS_UNKNOWN,
42 AARCH64_INSN_CLS_UNKNOWN,
43 AARCH64_INSN_CLS_UNKNOWN,
44 AARCH64_INSN_CLS_LDST,
45 AARCH64_INSN_CLS_DP_REG,
46 AARCH64_INSN_CLS_LDST,
47 AARCH64_INSN_CLS_DP_FPSIMD,
48 AARCH64_INSN_CLS_DP_IMM,
49 AARCH64_INSN_CLS_DP_IMM,
50 AARCH64_INSN_CLS_BR_SYS,
51 AARCH64_INSN_CLS_BR_SYS,
52 AARCH64_INSN_CLS_LDST,
53 AARCH64_INSN_CLS_DP_REG,
54 AARCH64_INSN_CLS_LDST,
55 AARCH64_INSN_CLS_DP_FPSIMD,
56 };
57
aarch64_get_insn_class(u32 insn)58 enum aarch64_insn_encoding_class __kprobes aarch64_get_insn_class(u32 insn)
59 {
60 return aarch64_insn_encoding_class[(insn >> 25) & 0xf];
61 }
62
63 /* NOP is an alias of HINT */
aarch64_insn_is_nop(u32 insn)64 bool __kprobes aarch64_insn_is_nop(u32 insn)
65 {
66 if (!aarch64_insn_is_hint(insn))
67 return false;
68
69 switch (insn & 0xFE0) {
70 case AARCH64_INSN_HINT_YIELD:
71 case AARCH64_INSN_HINT_WFE:
72 case AARCH64_INSN_HINT_WFI:
73 case AARCH64_INSN_HINT_SEV:
74 case AARCH64_INSN_HINT_SEVL:
75 return false;
76 default:
77 return true;
78 }
79 }
80
aarch64_insn_is_branch_imm(u32 insn)81 bool aarch64_insn_is_branch_imm(u32 insn)
82 {
83 return (aarch64_insn_is_b(insn) || aarch64_insn_is_bl(insn) ||
84 aarch64_insn_is_tbz(insn) || aarch64_insn_is_tbnz(insn) ||
85 aarch64_insn_is_cbz(insn) || aarch64_insn_is_cbnz(insn) ||
86 aarch64_insn_is_bcond(insn));
87 }
88
89 static DEFINE_RAW_SPINLOCK(patch_lock);
90
patch_map(void * addr,int fixmap)91 static void __kprobes *patch_map(void *addr, int fixmap)
92 {
93 unsigned long uintaddr = (uintptr_t) addr;
94 bool module = !core_kernel_text(uintaddr);
95 struct page *page;
96
97 if (module && IS_ENABLED(CONFIG_DEBUG_SET_MODULE_RONX))
98 page = vmalloc_to_page(addr);
99 else if (!module)
100 page = phys_to_page(__pa_symbol(addr));
101 else
102 return addr;
103
104 BUG_ON(!page);
105 return (void *)set_fixmap_offset(fixmap, page_to_phys(page) +
106 (uintaddr & ~PAGE_MASK));
107 }
108
patch_unmap(int fixmap)109 static void __kprobes patch_unmap(int fixmap)
110 {
111 clear_fixmap(fixmap);
112 }
113 /*
114 * In ARMv8-A, A64 instructions have a fixed length of 32 bits and are always
115 * little-endian.
116 */
aarch64_insn_read(void * addr,u32 * insnp)117 int __kprobes aarch64_insn_read(void *addr, u32 *insnp)
118 {
119 int ret;
120 u32 val;
121
122 ret = probe_kernel_read(&val, addr, AARCH64_INSN_SIZE);
123 if (!ret)
124 *insnp = le32_to_cpu(val);
125
126 return ret;
127 }
128
__aarch64_insn_write(void * addr,u32 insn)129 static int __kprobes __aarch64_insn_write(void *addr, u32 insn)
130 {
131 void *waddr = addr;
132 unsigned long flags = 0;
133 int ret;
134
135 raw_spin_lock_irqsave(&patch_lock, flags);
136 waddr = patch_map(addr, FIX_TEXT_POKE0);
137
138 ret = probe_kernel_write(waddr, &insn, AARCH64_INSN_SIZE);
139
140 patch_unmap(FIX_TEXT_POKE0);
141 raw_spin_unlock_irqrestore(&patch_lock, flags);
142
143 return ret;
144 }
145
aarch64_insn_write(void * addr,u32 insn)146 int __kprobes aarch64_insn_write(void *addr, u32 insn)
147 {
148 insn = cpu_to_le32(insn);
149 return __aarch64_insn_write(addr, insn);
150 }
151
__aarch64_insn_hotpatch_safe(u32 insn)152 static bool __kprobes __aarch64_insn_hotpatch_safe(u32 insn)
153 {
154 if (aarch64_get_insn_class(insn) != AARCH64_INSN_CLS_BR_SYS)
155 return false;
156
157 return aarch64_insn_is_b(insn) ||
158 aarch64_insn_is_bl(insn) ||
159 aarch64_insn_is_svc(insn) ||
160 aarch64_insn_is_hvc(insn) ||
161 aarch64_insn_is_smc(insn) ||
162 aarch64_insn_is_brk(insn) ||
163 aarch64_insn_is_nop(insn);
164 }
165
aarch64_insn_uses_literal(u32 insn)166 bool __kprobes aarch64_insn_uses_literal(u32 insn)
167 {
168 /* ldr/ldrsw (literal), prfm */
169
170 return aarch64_insn_is_ldr_lit(insn) ||
171 aarch64_insn_is_ldrsw_lit(insn) ||
172 aarch64_insn_is_adr_adrp(insn) ||
173 aarch64_insn_is_prfm_lit(insn);
174 }
175
aarch64_insn_is_branch(u32 insn)176 bool __kprobes aarch64_insn_is_branch(u32 insn)
177 {
178 /* b, bl, cb*, tb*, b.cond, br, blr */
179
180 return aarch64_insn_is_b(insn) ||
181 aarch64_insn_is_bl(insn) ||
182 aarch64_insn_is_cbz(insn) ||
183 aarch64_insn_is_cbnz(insn) ||
184 aarch64_insn_is_tbz(insn) ||
185 aarch64_insn_is_tbnz(insn) ||
186 aarch64_insn_is_ret(insn) ||
187 aarch64_insn_is_br(insn) ||
188 aarch64_insn_is_blr(insn) ||
189 aarch64_insn_is_bcond(insn);
190 }
191
192 /*
193 * ARM Architecture Reference Manual for ARMv8 Profile-A, Issue A.a
194 * Section B2.6.5 "Concurrent modification and execution of instructions":
195 * Concurrent modification and execution of instructions can lead to the
196 * resulting instruction performing any behavior that can be achieved by
197 * executing any sequence of instructions that can be executed from the
198 * same Exception level, except where the instruction before modification
199 * and the instruction after modification is a B, BL, NOP, BKPT, SVC, HVC,
200 * or SMC instruction.
201 */
aarch64_insn_hotpatch_safe(u32 old_insn,u32 new_insn)202 bool __kprobes aarch64_insn_hotpatch_safe(u32 old_insn, u32 new_insn)
203 {
204 return __aarch64_insn_hotpatch_safe(old_insn) &&
205 __aarch64_insn_hotpatch_safe(new_insn);
206 }
207
aarch64_insn_patch_text_nosync(void * addr,u32 insn)208 int __kprobes aarch64_insn_patch_text_nosync(void *addr, u32 insn)
209 {
210 u32 *tp = addr;
211 int ret;
212
213 /* A64 instructions must be word aligned */
214 if ((uintptr_t)tp & 0x3)
215 return -EINVAL;
216
217 ret = aarch64_insn_write(tp, insn);
218 if (ret == 0)
219 flush_icache_range((uintptr_t)tp,
220 (uintptr_t)tp + AARCH64_INSN_SIZE);
221
222 return ret;
223 }
224
225 struct aarch64_insn_patch {
226 void **text_addrs;
227 u32 *new_insns;
228 int insn_cnt;
229 atomic_t cpu_count;
230 };
231
aarch64_insn_patch_text_cb(void * arg)232 static int __kprobes aarch64_insn_patch_text_cb(void *arg)
233 {
234 int i, ret = 0;
235 struct aarch64_insn_patch *pp = arg;
236
237 /* The first CPU becomes master */
238 if (atomic_inc_return(&pp->cpu_count) == 1) {
239 for (i = 0; ret == 0 && i < pp->insn_cnt; i++)
240 ret = aarch64_insn_patch_text_nosync(pp->text_addrs[i],
241 pp->new_insns[i]);
242 /*
243 * aarch64_insn_patch_text_nosync() calls flush_icache_range(),
244 * which ends with "dsb; isb" pair guaranteeing global
245 * visibility.
246 */
247 /* Notify other processors with an additional increment. */
248 atomic_inc(&pp->cpu_count);
249 } else {
250 while (atomic_read(&pp->cpu_count) <= num_online_cpus())
251 cpu_relax();
252 isb();
253 }
254
255 return ret;
256 }
257
aarch64_insn_patch_text_sync(void * addrs[],u32 insns[],int cnt)258 int __kprobes aarch64_insn_patch_text_sync(void *addrs[], u32 insns[], int cnt)
259 {
260 struct aarch64_insn_patch patch = {
261 .text_addrs = addrs,
262 .new_insns = insns,
263 .insn_cnt = cnt,
264 .cpu_count = ATOMIC_INIT(0),
265 };
266
267 if (cnt <= 0)
268 return -EINVAL;
269
270 return stop_machine(aarch64_insn_patch_text_cb, &patch,
271 cpu_online_mask);
272 }
273
aarch64_insn_patch_text(void * addrs[],u32 insns[],int cnt)274 int __kprobes aarch64_insn_patch_text(void *addrs[], u32 insns[], int cnt)
275 {
276 int ret;
277 u32 insn;
278
279 /* Unsafe to patch multiple instructions without synchronizaiton */
280 if (cnt == 1) {
281 ret = aarch64_insn_read(addrs[0], &insn);
282 if (ret)
283 return ret;
284
285 if (aarch64_insn_hotpatch_safe(insn, insns[0])) {
286 /*
287 * ARMv8 architecture doesn't guarantee all CPUs see
288 * the new instruction after returning from function
289 * aarch64_insn_patch_text_nosync(). So send IPIs to
290 * all other CPUs to achieve instruction
291 * synchronization.
292 */
293 ret = aarch64_insn_patch_text_nosync(addrs[0], insns[0]);
294 kick_all_cpus_sync();
295 return ret;
296 }
297 }
298
299 return aarch64_insn_patch_text_sync(addrs, insns, cnt);
300 }
301
aarch64_get_imm_shift_mask(enum aarch64_insn_imm_type type,u32 * maskp,int * shiftp)302 static int __kprobes aarch64_get_imm_shift_mask(enum aarch64_insn_imm_type type,
303 u32 *maskp, int *shiftp)
304 {
305 u32 mask;
306 int shift;
307
308 switch (type) {
309 case AARCH64_INSN_IMM_26:
310 mask = BIT(26) - 1;
311 shift = 0;
312 break;
313 case AARCH64_INSN_IMM_19:
314 mask = BIT(19) - 1;
315 shift = 5;
316 break;
317 case AARCH64_INSN_IMM_16:
318 mask = BIT(16) - 1;
319 shift = 5;
320 break;
321 case AARCH64_INSN_IMM_14:
322 mask = BIT(14) - 1;
323 shift = 5;
324 break;
325 case AARCH64_INSN_IMM_12:
326 mask = BIT(12) - 1;
327 shift = 10;
328 break;
329 case AARCH64_INSN_IMM_9:
330 mask = BIT(9) - 1;
331 shift = 12;
332 break;
333 case AARCH64_INSN_IMM_7:
334 mask = BIT(7) - 1;
335 shift = 15;
336 break;
337 case AARCH64_INSN_IMM_6:
338 case AARCH64_INSN_IMM_S:
339 mask = BIT(6) - 1;
340 shift = 10;
341 break;
342 case AARCH64_INSN_IMM_R:
343 mask = BIT(6) - 1;
344 shift = 16;
345 break;
346 default:
347 return -EINVAL;
348 }
349
350 *maskp = mask;
351 *shiftp = shift;
352
353 return 0;
354 }
355
356 #define ADR_IMM_HILOSPLIT 2
357 #define ADR_IMM_SIZE SZ_2M
358 #define ADR_IMM_LOMASK ((1 << ADR_IMM_HILOSPLIT) - 1)
359 #define ADR_IMM_HIMASK ((ADR_IMM_SIZE >> ADR_IMM_HILOSPLIT) - 1)
360 #define ADR_IMM_LOSHIFT 29
361 #define ADR_IMM_HISHIFT 5
362
aarch64_insn_decode_immediate(enum aarch64_insn_imm_type type,u32 insn)363 u64 aarch64_insn_decode_immediate(enum aarch64_insn_imm_type type, u32 insn)
364 {
365 u32 immlo, immhi, mask;
366 int shift;
367
368 switch (type) {
369 case AARCH64_INSN_IMM_ADR:
370 shift = 0;
371 immlo = (insn >> ADR_IMM_LOSHIFT) & ADR_IMM_LOMASK;
372 immhi = (insn >> ADR_IMM_HISHIFT) & ADR_IMM_HIMASK;
373 insn = (immhi << ADR_IMM_HILOSPLIT) | immlo;
374 mask = ADR_IMM_SIZE - 1;
375 break;
376 default:
377 if (aarch64_get_imm_shift_mask(type, &mask, &shift) < 0) {
378 pr_err("aarch64_insn_decode_immediate: unknown immediate encoding %d\n",
379 type);
380 return 0;
381 }
382 }
383
384 return (insn >> shift) & mask;
385 }
386
aarch64_insn_encode_immediate(enum aarch64_insn_imm_type type,u32 insn,u64 imm)387 u32 __kprobes aarch64_insn_encode_immediate(enum aarch64_insn_imm_type type,
388 u32 insn, u64 imm)
389 {
390 u32 immlo, immhi, mask;
391 int shift;
392
393 if (insn == AARCH64_BREAK_FAULT)
394 return AARCH64_BREAK_FAULT;
395
396 switch (type) {
397 case AARCH64_INSN_IMM_ADR:
398 shift = 0;
399 immlo = (imm & ADR_IMM_LOMASK) << ADR_IMM_LOSHIFT;
400 imm >>= ADR_IMM_HILOSPLIT;
401 immhi = (imm & ADR_IMM_HIMASK) << ADR_IMM_HISHIFT;
402 imm = immlo | immhi;
403 mask = ((ADR_IMM_LOMASK << ADR_IMM_LOSHIFT) |
404 (ADR_IMM_HIMASK << ADR_IMM_HISHIFT));
405 break;
406 default:
407 if (aarch64_get_imm_shift_mask(type, &mask, &shift) < 0) {
408 pr_err("aarch64_insn_encode_immediate: unknown immediate encoding %d\n",
409 type);
410 return AARCH64_BREAK_FAULT;
411 }
412 }
413
414 /* Update the immediate field. */
415 insn &= ~(mask << shift);
416 insn |= (imm & mask) << shift;
417
418 return insn;
419 }
420
aarch64_insn_encode_register(enum aarch64_insn_register_type type,u32 insn,enum aarch64_insn_register reg)421 static u32 aarch64_insn_encode_register(enum aarch64_insn_register_type type,
422 u32 insn,
423 enum aarch64_insn_register reg)
424 {
425 int shift;
426
427 if (insn == AARCH64_BREAK_FAULT)
428 return AARCH64_BREAK_FAULT;
429
430 if (reg < AARCH64_INSN_REG_0 || reg > AARCH64_INSN_REG_SP) {
431 pr_err("%s: unknown register encoding %d\n", __func__, reg);
432 return AARCH64_BREAK_FAULT;
433 }
434
435 switch (type) {
436 case AARCH64_INSN_REGTYPE_RT:
437 case AARCH64_INSN_REGTYPE_RD:
438 shift = 0;
439 break;
440 case AARCH64_INSN_REGTYPE_RN:
441 shift = 5;
442 break;
443 case AARCH64_INSN_REGTYPE_RT2:
444 case AARCH64_INSN_REGTYPE_RA:
445 shift = 10;
446 break;
447 case AARCH64_INSN_REGTYPE_RM:
448 shift = 16;
449 break;
450 default:
451 pr_err("%s: unknown register type encoding %d\n", __func__,
452 type);
453 return AARCH64_BREAK_FAULT;
454 }
455
456 insn &= ~(GENMASK(4, 0) << shift);
457 insn |= reg << shift;
458
459 return insn;
460 }
461
aarch64_insn_encode_ldst_size(enum aarch64_insn_size_type type,u32 insn)462 static u32 aarch64_insn_encode_ldst_size(enum aarch64_insn_size_type type,
463 u32 insn)
464 {
465 u32 size;
466
467 switch (type) {
468 case AARCH64_INSN_SIZE_8:
469 size = 0;
470 break;
471 case AARCH64_INSN_SIZE_16:
472 size = 1;
473 break;
474 case AARCH64_INSN_SIZE_32:
475 size = 2;
476 break;
477 case AARCH64_INSN_SIZE_64:
478 size = 3;
479 break;
480 default:
481 pr_err("%s: unknown size encoding %d\n", __func__, type);
482 return AARCH64_BREAK_FAULT;
483 }
484
485 insn &= ~GENMASK(31, 30);
486 insn |= size << 30;
487
488 return insn;
489 }
490
branch_imm_common(unsigned long pc,unsigned long addr,long range)491 static inline long branch_imm_common(unsigned long pc, unsigned long addr,
492 long range)
493 {
494 long offset;
495
496 if ((pc & 0x3) || (addr & 0x3)) {
497 pr_err("%s: A64 instructions must be word aligned\n", __func__);
498 return range;
499 }
500
501 offset = ((long)addr - (long)pc);
502
503 if (offset < -range || offset >= range) {
504 pr_err("%s: offset out of range\n", __func__);
505 return range;
506 }
507
508 return offset;
509 }
510
aarch64_insn_gen_branch_imm(unsigned long pc,unsigned long addr,enum aarch64_insn_branch_type type)511 u32 __kprobes aarch64_insn_gen_branch_imm(unsigned long pc, unsigned long addr,
512 enum aarch64_insn_branch_type type)
513 {
514 u32 insn;
515 long offset;
516
517 /*
518 * B/BL support [-128M, 128M) offset
519 * ARM64 virtual address arrangement guarantees all kernel and module
520 * texts are within +/-128M.
521 */
522 offset = branch_imm_common(pc, addr, SZ_128M);
523 if (offset >= SZ_128M)
524 return AARCH64_BREAK_FAULT;
525
526 switch (type) {
527 case AARCH64_INSN_BRANCH_LINK:
528 insn = aarch64_insn_get_bl_value();
529 break;
530 case AARCH64_INSN_BRANCH_NOLINK:
531 insn = aarch64_insn_get_b_value();
532 break;
533 default:
534 pr_err("%s: unknown branch encoding %d\n", __func__, type);
535 return AARCH64_BREAK_FAULT;
536 }
537
538 return aarch64_insn_encode_immediate(AARCH64_INSN_IMM_26, insn,
539 offset >> 2);
540 }
541
aarch64_insn_gen_comp_branch_imm(unsigned long pc,unsigned long addr,enum aarch64_insn_register reg,enum aarch64_insn_variant variant,enum aarch64_insn_branch_type type)542 u32 aarch64_insn_gen_comp_branch_imm(unsigned long pc, unsigned long addr,
543 enum aarch64_insn_register reg,
544 enum aarch64_insn_variant variant,
545 enum aarch64_insn_branch_type type)
546 {
547 u32 insn;
548 long offset;
549
550 offset = branch_imm_common(pc, addr, SZ_1M);
551 if (offset >= SZ_1M)
552 return AARCH64_BREAK_FAULT;
553
554 switch (type) {
555 case AARCH64_INSN_BRANCH_COMP_ZERO:
556 insn = aarch64_insn_get_cbz_value();
557 break;
558 case AARCH64_INSN_BRANCH_COMP_NONZERO:
559 insn = aarch64_insn_get_cbnz_value();
560 break;
561 default:
562 pr_err("%s: unknown branch encoding %d\n", __func__, type);
563 return AARCH64_BREAK_FAULT;
564 }
565
566 switch (variant) {
567 case AARCH64_INSN_VARIANT_32BIT:
568 break;
569 case AARCH64_INSN_VARIANT_64BIT:
570 insn |= AARCH64_INSN_SF_BIT;
571 break;
572 default:
573 pr_err("%s: unknown variant encoding %d\n", __func__, variant);
574 return AARCH64_BREAK_FAULT;
575 }
576
577 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RT, insn, reg);
578
579 return aarch64_insn_encode_immediate(AARCH64_INSN_IMM_19, insn,
580 offset >> 2);
581 }
582
aarch64_insn_gen_cond_branch_imm(unsigned long pc,unsigned long addr,enum aarch64_insn_condition cond)583 u32 aarch64_insn_gen_cond_branch_imm(unsigned long pc, unsigned long addr,
584 enum aarch64_insn_condition cond)
585 {
586 u32 insn;
587 long offset;
588
589 offset = branch_imm_common(pc, addr, SZ_1M);
590
591 insn = aarch64_insn_get_bcond_value();
592
593 if (cond < AARCH64_INSN_COND_EQ || cond > AARCH64_INSN_COND_AL) {
594 pr_err("%s: unknown condition encoding %d\n", __func__, cond);
595 return AARCH64_BREAK_FAULT;
596 }
597 insn |= cond;
598
599 return aarch64_insn_encode_immediate(AARCH64_INSN_IMM_19, insn,
600 offset >> 2);
601 }
602
aarch64_insn_gen_hint(enum aarch64_insn_hint_op op)603 u32 __kprobes aarch64_insn_gen_hint(enum aarch64_insn_hint_op op)
604 {
605 return aarch64_insn_get_hint_value() | op;
606 }
607
aarch64_insn_gen_nop(void)608 u32 __kprobes aarch64_insn_gen_nop(void)
609 {
610 return aarch64_insn_gen_hint(AARCH64_INSN_HINT_NOP);
611 }
612
aarch64_insn_gen_branch_reg(enum aarch64_insn_register reg,enum aarch64_insn_branch_type type)613 u32 aarch64_insn_gen_branch_reg(enum aarch64_insn_register reg,
614 enum aarch64_insn_branch_type type)
615 {
616 u32 insn;
617
618 switch (type) {
619 case AARCH64_INSN_BRANCH_NOLINK:
620 insn = aarch64_insn_get_br_value();
621 break;
622 case AARCH64_INSN_BRANCH_LINK:
623 insn = aarch64_insn_get_blr_value();
624 break;
625 case AARCH64_INSN_BRANCH_RETURN:
626 insn = aarch64_insn_get_ret_value();
627 break;
628 default:
629 pr_err("%s: unknown branch encoding %d\n", __func__, type);
630 return AARCH64_BREAK_FAULT;
631 }
632
633 return aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RN, insn, reg);
634 }
635
aarch64_insn_gen_load_store_reg(enum aarch64_insn_register reg,enum aarch64_insn_register base,enum aarch64_insn_register offset,enum aarch64_insn_size_type size,enum aarch64_insn_ldst_type type)636 u32 aarch64_insn_gen_load_store_reg(enum aarch64_insn_register reg,
637 enum aarch64_insn_register base,
638 enum aarch64_insn_register offset,
639 enum aarch64_insn_size_type size,
640 enum aarch64_insn_ldst_type type)
641 {
642 u32 insn;
643
644 switch (type) {
645 case AARCH64_INSN_LDST_LOAD_REG_OFFSET:
646 insn = aarch64_insn_get_ldr_reg_value();
647 break;
648 case AARCH64_INSN_LDST_STORE_REG_OFFSET:
649 insn = aarch64_insn_get_str_reg_value();
650 break;
651 default:
652 pr_err("%s: unknown load/store encoding %d\n", __func__, type);
653 return AARCH64_BREAK_FAULT;
654 }
655
656 insn = aarch64_insn_encode_ldst_size(size, insn);
657
658 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RT, insn, reg);
659
660 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RN, insn,
661 base);
662
663 return aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RM, insn,
664 offset);
665 }
666
aarch64_insn_gen_load_store_pair(enum aarch64_insn_register reg1,enum aarch64_insn_register reg2,enum aarch64_insn_register base,int offset,enum aarch64_insn_variant variant,enum aarch64_insn_ldst_type type)667 u32 aarch64_insn_gen_load_store_pair(enum aarch64_insn_register reg1,
668 enum aarch64_insn_register reg2,
669 enum aarch64_insn_register base,
670 int offset,
671 enum aarch64_insn_variant variant,
672 enum aarch64_insn_ldst_type type)
673 {
674 u32 insn;
675 int shift;
676
677 switch (type) {
678 case AARCH64_INSN_LDST_LOAD_PAIR_PRE_INDEX:
679 insn = aarch64_insn_get_ldp_pre_value();
680 break;
681 case AARCH64_INSN_LDST_STORE_PAIR_PRE_INDEX:
682 insn = aarch64_insn_get_stp_pre_value();
683 break;
684 case AARCH64_INSN_LDST_LOAD_PAIR_POST_INDEX:
685 insn = aarch64_insn_get_ldp_post_value();
686 break;
687 case AARCH64_INSN_LDST_STORE_PAIR_POST_INDEX:
688 insn = aarch64_insn_get_stp_post_value();
689 break;
690 default:
691 pr_err("%s: unknown load/store encoding %d\n", __func__, type);
692 return AARCH64_BREAK_FAULT;
693 }
694
695 switch (variant) {
696 case AARCH64_INSN_VARIANT_32BIT:
697 if ((offset & 0x3) || (offset < -256) || (offset > 252)) {
698 pr_err("%s: offset must be multiples of 4 in the range of [-256, 252] %d\n",
699 __func__, offset);
700 return AARCH64_BREAK_FAULT;
701 }
702 shift = 2;
703 break;
704 case AARCH64_INSN_VARIANT_64BIT:
705 if ((offset & 0x7) || (offset < -512) || (offset > 504)) {
706 pr_err("%s: offset must be multiples of 8 in the range of [-512, 504] %d\n",
707 __func__, offset);
708 return AARCH64_BREAK_FAULT;
709 }
710 shift = 3;
711 insn |= AARCH64_INSN_SF_BIT;
712 break;
713 default:
714 pr_err("%s: unknown variant encoding %d\n", __func__, variant);
715 return AARCH64_BREAK_FAULT;
716 }
717
718 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RT, insn,
719 reg1);
720
721 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RT2, insn,
722 reg2);
723
724 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RN, insn,
725 base);
726
727 return aarch64_insn_encode_immediate(AARCH64_INSN_IMM_7, insn,
728 offset >> shift);
729 }
730
aarch64_insn_gen_add_sub_imm(enum aarch64_insn_register dst,enum aarch64_insn_register src,int imm,enum aarch64_insn_variant variant,enum aarch64_insn_adsb_type type)731 u32 aarch64_insn_gen_add_sub_imm(enum aarch64_insn_register dst,
732 enum aarch64_insn_register src,
733 int imm, enum aarch64_insn_variant variant,
734 enum aarch64_insn_adsb_type type)
735 {
736 u32 insn;
737
738 switch (type) {
739 case AARCH64_INSN_ADSB_ADD:
740 insn = aarch64_insn_get_add_imm_value();
741 break;
742 case AARCH64_INSN_ADSB_SUB:
743 insn = aarch64_insn_get_sub_imm_value();
744 break;
745 case AARCH64_INSN_ADSB_ADD_SETFLAGS:
746 insn = aarch64_insn_get_adds_imm_value();
747 break;
748 case AARCH64_INSN_ADSB_SUB_SETFLAGS:
749 insn = aarch64_insn_get_subs_imm_value();
750 break;
751 default:
752 pr_err("%s: unknown add/sub encoding %d\n", __func__, type);
753 return AARCH64_BREAK_FAULT;
754 }
755
756 switch (variant) {
757 case AARCH64_INSN_VARIANT_32BIT:
758 break;
759 case AARCH64_INSN_VARIANT_64BIT:
760 insn |= AARCH64_INSN_SF_BIT;
761 break;
762 default:
763 pr_err("%s: unknown variant encoding %d\n", __func__, variant);
764 return AARCH64_BREAK_FAULT;
765 }
766
767 if (imm & ~(SZ_4K - 1)) {
768 pr_err("%s: invalid immediate encoding %d\n", __func__, imm);
769 return AARCH64_BREAK_FAULT;
770 }
771
772 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RD, insn, dst);
773
774 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RN, insn, src);
775
776 return aarch64_insn_encode_immediate(AARCH64_INSN_IMM_12, insn, imm);
777 }
778
aarch64_insn_gen_bitfield(enum aarch64_insn_register dst,enum aarch64_insn_register src,int immr,int imms,enum aarch64_insn_variant variant,enum aarch64_insn_bitfield_type type)779 u32 aarch64_insn_gen_bitfield(enum aarch64_insn_register dst,
780 enum aarch64_insn_register src,
781 int immr, int imms,
782 enum aarch64_insn_variant variant,
783 enum aarch64_insn_bitfield_type type)
784 {
785 u32 insn;
786 u32 mask;
787
788 switch (type) {
789 case AARCH64_INSN_BITFIELD_MOVE:
790 insn = aarch64_insn_get_bfm_value();
791 break;
792 case AARCH64_INSN_BITFIELD_MOVE_UNSIGNED:
793 insn = aarch64_insn_get_ubfm_value();
794 break;
795 case AARCH64_INSN_BITFIELD_MOVE_SIGNED:
796 insn = aarch64_insn_get_sbfm_value();
797 break;
798 default:
799 pr_err("%s: unknown bitfield encoding %d\n", __func__, type);
800 return AARCH64_BREAK_FAULT;
801 }
802
803 switch (variant) {
804 case AARCH64_INSN_VARIANT_32BIT:
805 mask = GENMASK(4, 0);
806 break;
807 case AARCH64_INSN_VARIANT_64BIT:
808 insn |= AARCH64_INSN_SF_BIT | AARCH64_INSN_N_BIT;
809 mask = GENMASK(5, 0);
810 break;
811 default:
812 pr_err("%s: unknown variant encoding %d\n", __func__, variant);
813 return AARCH64_BREAK_FAULT;
814 }
815
816 if (immr & ~mask) {
817 pr_err("%s: invalid immr encoding %d\n", __func__, immr);
818 return AARCH64_BREAK_FAULT;
819 }
820 if (imms & ~mask) {
821 pr_err("%s: invalid imms encoding %d\n", __func__, imms);
822 return AARCH64_BREAK_FAULT;
823 }
824
825 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RD, insn, dst);
826
827 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RN, insn, src);
828
829 insn = aarch64_insn_encode_immediate(AARCH64_INSN_IMM_R, insn, immr);
830
831 return aarch64_insn_encode_immediate(AARCH64_INSN_IMM_S, insn, imms);
832 }
833
aarch64_insn_gen_movewide(enum aarch64_insn_register dst,int imm,int shift,enum aarch64_insn_variant variant,enum aarch64_insn_movewide_type type)834 u32 aarch64_insn_gen_movewide(enum aarch64_insn_register dst,
835 int imm, int shift,
836 enum aarch64_insn_variant variant,
837 enum aarch64_insn_movewide_type type)
838 {
839 u32 insn;
840
841 switch (type) {
842 case AARCH64_INSN_MOVEWIDE_ZERO:
843 insn = aarch64_insn_get_movz_value();
844 break;
845 case AARCH64_INSN_MOVEWIDE_KEEP:
846 insn = aarch64_insn_get_movk_value();
847 break;
848 case AARCH64_INSN_MOVEWIDE_INVERSE:
849 insn = aarch64_insn_get_movn_value();
850 break;
851 default:
852 pr_err("%s: unknown movewide encoding %d\n", __func__, type);
853 return AARCH64_BREAK_FAULT;
854 }
855
856 if (imm & ~(SZ_64K - 1)) {
857 pr_err("%s: invalid immediate encoding %d\n", __func__, imm);
858 return AARCH64_BREAK_FAULT;
859 }
860
861 switch (variant) {
862 case AARCH64_INSN_VARIANT_32BIT:
863 if (shift != 0 && shift != 16) {
864 pr_err("%s: invalid shift encoding %d\n", __func__,
865 shift);
866 return AARCH64_BREAK_FAULT;
867 }
868 break;
869 case AARCH64_INSN_VARIANT_64BIT:
870 insn |= AARCH64_INSN_SF_BIT;
871 if (shift != 0 && shift != 16 && shift != 32 && shift != 48) {
872 pr_err("%s: invalid shift encoding %d\n", __func__,
873 shift);
874 return AARCH64_BREAK_FAULT;
875 }
876 break;
877 default:
878 pr_err("%s: unknown variant encoding %d\n", __func__, variant);
879 return AARCH64_BREAK_FAULT;
880 }
881
882 insn |= (shift >> 4) << 21;
883
884 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RD, insn, dst);
885
886 return aarch64_insn_encode_immediate(AARCH64_INSN_IMM_16, insn, imm);
887 }
888
aarch64_insn_gen_add_sub_shifted_reg(enum aarch64_insn_register dst,enum aarch64_insn_register src,enum aarch64_insn_register reg,int shift,enum aarch64_insn_variant variant,enum aarch64_insn_adsb_type type)889 u32 aarch64_insn_gen_add_sub_shifted_reg(enum aarch64_insn_register dst,
890 enum aarch64_insn_register src,
891 enum aarch64_insn_register reg,
892 int shift,
893 enum aarch64_insn_variant variant,
894 enum aarch64_insn_adsb_type type)
895 {
896 u32 insn;
897
898 switch (type) {
899 case AARCH64_INSN_ADSB_ADD:
900 insn = aarch64_insn_get_add_value();
901 break;
902 case AARCH64_INSN_ADSB_SUB:
903 insn = aarch64_insn_get_sub_value();
904 break;
905 case AARCH64_INSN_ADSB_ADD_SETFLAGS:
906 insn = aarch64_insn_get_adds_value();
907 break;
908 case AARCH64_INSN_ADSB_SUB_SETFLAGS:
909 insn = aarch64_insn_get_subs_value();
910 break;
911 default:
912 pr_err("%s: unknown add/sub encoding %d\n", __func__, type);
913 return AARCH64_BREAK_FAULT;
914 }
915
916 switch (variant) {
917 case AARCH64_INSN_VARIANT_32BIT:
918 if (shift & ~(SZ_32 - 1)) {
919 pr_err("%s: invalid shift encoding %d\n", __func__,
920 shift);
921 return AARCH64_BREAK_FAULT;
922 }
923 break;
924 case AARCH64_INSN_VARIANT_64BIT:
925 insn |= AARCH64_INSN_SF_BIT;
926 if (shift & ~(SZ_64 - 1)) {
927 pr_err("%s: invalid shift encoding %d\n", __func__,
928 shift);
929 return AARCH64_BREAK_FAULT;
930 }
931 break;
932 default:
933 pr_err("%s: unknown variant encoding %d\n", __func__, variant);
934 return AARCH64_BREAK_FAULT;
935 }
936
937
938 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RD, insn, dst);
939
940 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RN, insn, src);
941
942 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RM, insn, reg);
943
944 return aarch64_insn_encode_immediate(AARCH64_INSN_IMM_6, insn, shift);
945 }
946
aarch64_insn_gen_data1(enum aarch64_insn_register dst,enum aarch64_insn_register src,enum aarch64_insn_variant variant,enum aarch64_insn_data1_type type)947 u32 aarch64_insn_gen_data1(enum aarch64_insn_register dst,
948 enum aarch64_insn_register src,
949 enum aarch64_insn_variant variant,
950 enum aarch64_insn_data1_type type)
951 {
952 u32 insn;
953
954 switch (type) {
955 case AARCH64_INSN_DATA1_REVERSE_16:
956 insn = aarch64_insn_get_rev16_value();
957 break;
958 case AARCH64_INSN_DATA1_REVERSE_32:
959 insn = aarch64_insn_get_rev32_value();
960 break;
961 case AARCH64_INSN_DATA1_REVERSE_64:
962 if (variant != AARCH64_INSN_VARIANT_64BIT) {
963 pr_err("%s: invalid variant for reverse64 %d\n",
964 __func__, variant);
965 return AARCH64_BREAK_FAULT;
966 }
967 insn = aarch64_insn_get_rev64_value();
968 break;
969 default:
970 pr_err("%s: unknown data1 encoding %d\n", __func__, type);
971 return AARCH64_BREAK_FAULT;
972 }
973
974 switch (variant) {
975 case AARCH64_INSN_VARIANT_32BIT:
976 break;
977 case AARCH64_INSN_VARIANT_64BIT:
978 insn |= AARCH64_INSN_SF_BIT;
979 break;
980 default:
981 pr_err("%s: unknown variant encoding %d\n", __func__, variant);
982 return AARCH64_BREAK_FAULT;
983 }
984
985 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RD, insn, dst);
986
987 return aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RN, insn, src);
988 }
989
aarch64_insn_gen_data2(enum aarch64_insn_register dst,enum aarch64_insn_register src,enum aarch64_insn_register reg,enum aarch64_insn_variant variant,enum aarch64_insn_data2_type type)990 u32 aarch64_insn_gen_data2(enum aarch64_insn_register dst,
991 enum aarch64_insn_register src,
992 enum aarch64_insn_register reg,
993 enum aarch64_insn_variant variant,
994 enum aarch64_insn_data2_type type)
995 {
996 u32 insn;
997
998 switch (type) {
999 case AARCH64_INSN_DATA2_UDIV:
1000 insn = aarch64_insn_get_udiv_value();
1001 break;
1002 case AARCH64_INSN_DATA2_SDIV:
1003 insn = aarch64_insn_get_sdiv_value();
1004 break;
1005 case AARCH64_INSN_DATA2_LSLV:
1006 insn = aarch64_insn_get_lslv_value();
1007 break;
1008 case AARCH64_INSN_DATA2_LSRV:
1009 insn = aarch64_insn_get_lsrv_value();
1010 break;
1011 case AARCH64_INSN_DATA2_ASRV:
1012 insn = aarch64_insn_get_asrv_value();
1013 break;
1014 case AARCH64_INSN_DATA2_RORV:
1015 insn = aarch64_insn_get_rorv_value();
1016 break;
1017 default:
1018 pr_err("%s: unknown data2 encoding %d\n", __func__, type);
1019 return AARCH64_BREAK_FAULT;
1020 }
1021
1022 switch (variant) {
1023 case AARCH64_INSN_VARIANT_32BIT:
1024 break;
1025 case AARCH64_INSN_VARIANT_64BIT:
1026 insn |= AARCH64_INSN_SF_BIT;
1027 break;
1028 default:
1029 pr_err("%s: unknown variant encoding %d\n", __func__, variant);
1030 return AARCH64_BREAK_FAULT;
1031 }
1032
1033 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RD, insn, dst);
1034
1035 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RN, insn, src);
1036
1037 return aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RM, insn, reg);
1038 }
1039
aarch64_insn_gen_data3(enum aarch64_insn_register dst,enum aarch64_insn_register src,enum aarch64_insn_register reg1,enum aarch64_insn_register reg2,enum aarch64_insn_variant variant,enum aarch64_insn_data3_type type)1040 u32 aarch64_insn_gen_data3(enum aarch64_insn_register dst,
1041 enum aarch64_insn_register src,
1042 enum aarch64_insn_register reg1,
1043 enum aarch64_insn_register reg2,
1044 enum aarch64_insn_variant variant,
1045 enum aarch64_insn_data3_type type)
1046 {
1047 u32 insn;
1048
1049 switch (type) {
1050 case AARCH64_INSN_DATA3_MADD:
1051 insn = aarch64_insn_get_madd_value();
1052 break;
1053 case AARCH64_INSN_DATA3_MSUB:
1054 insn = aarch64_insn_get_msub_value();
1055 break;
1056 default:
1057 pr_err("%s: unknown data3 encoding %d\n", __func__, type);
1058 return AARCH64_BREAK_FAULT;
1059 }
1060
1061 switch (variant) {
1062 case AARCH64_INSN_VARIANT_32BIT:
1063 break;
1064 case AARCH64_INSN_VARIANT_64BIT:
1065 insn |= AARCH64_INSN_SF_BIT;
1066 break;
1067 default:
1068 pr_err("%s: unknown variant encoding %d\n", __func__, variant);
1069 return AARCH64_BREAK_FAULT;
1070 }
1071
1072 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RD, insn, dst);
1073
1074 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RA, insn, src);
1075
1076 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RN, insn,
1077 reg1);
1078
1079 return aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RM, insn,
1080 reg2);
1081 }
1082
aarch64_insn_gen_logical_shifted_reg(enum aarch64_insn_register dst,enum aarch64_insn_register src,enum aarch64_insn_register reg,int shift,enum aarch64_insn_variant variant,enum aarch64_insn_logic_type type)1083 u32 aarch64_insn_gen_logical_shifted_reg(enum aarch64_insn_register dst,
1084 enum aarch64_insn_register src,
1085 enum aarch64_insn_register reg,
1086 int shift,
1087 enum aarch64_insn_variant variant,
1088 enum aarch64_insn_logic_type type)
1089 {
1090 u32 insn;
1091
1092 switch (type) {
1093 case AARCH64_INSN_LOGIC_AND:
1094 insn = aarch64_insn_get_and_value();
1095 break;
1096 case AARCH64_INSN_LOGIC_BIC:
1097 insn = aarch64_insn_get_bic_value();
1098 break;
1099 case AARCH64_INSN_LOGIC_ORR:
1100 insn = aarch64_insn_get_orr_value();
1101 break;
1102 case AARCH64_INSN_LOGIC_ORN:
1103 insn = aarch64_insn_get_orn_value();
1104 break;
1105 case AARCH64_INSN_LOGIC_EOR:
1106 insn = aarch64_insn_get_eor_value();
1107 break;
1108 case AARCH64_INSN_LOGIC_EON:
1109 insn = aarch64_insn_get_eon_value();
1110 break;
1111 case AARCH64_INSN_LOGIC_AND_SETFLAGS:
1112 insn = aarch64_insn_get_ands_value();
1113 break;
1114 case AARCH64_INSN_LOGIC_BIC_SETFLAGS:
1115 insn = aarch64_insn_get_bics_value();
1116 break;
1117 default:
1118 pr_err("%s: unknown logical encoding %d\n", __func__, type);
1119 return AARCH64_BREAK_FAULT;
1120 }
1121
1122 switch (variant) {
1123 case AARCH64_INSN_VARIANT_32BIT:
1124 if (shift & ~(SZ_32 - 1)) {
1125 pr_err("%s: invalid shift encoding %d\n", __func__,
1126 shift);
1127 return AARCH64_BREAK_FAULT;
1128 }
1129 break;
1130 case AARCH64_INSN_VARIANT_64BIT:
1131 insn |= AARCH64_INSN_SF_BIT;
1132 if (shift & ~(SZ_64 - 1)) {
1133 pr_err("%s: invalid shift encoding %d\n", __func__,
1134 shift);
1135 return AARCH64_BREAK_FAULT;
1136 }
1137 break;
1138 default:
1139 pr_err("%s: unknown variant encoding %d\n", __func__, variant);
1140 return AARCH64_BREAK_FAULT;
1141 }
1142
1143
1144 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RD, insn, dst);
1145
1146 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RN, insn, src);
1147
1148 insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RM, insn, reg);
1149
1150 return aarch64_insn_encode_immediate(AARCH64_INSN_IMM_6, insn, shift);
1151 }
1152
1153 /*
1154 * Decode the imm field of a branch, and return the byte offset as a
1155 * signed value (so it can be used when computing a new branch
1156 * target).
1157 */
aarch64_get_branch_offset(u32 insn)1158 s32 aarch64_get_branch_offset(u32 insn)
1159 {
1160 s32 imm;
1161
1162 if (aarch64_insn_is_b(insn) || aarch64_insn_is_bl(insn)) {
1163 imm = aarch64_insn_decode_immediate(AARCH64_INSN_IMM_26, insn);
1164 return (imm << 6) >> 4;
1165 }
1166
1167 if (aarch64_insn_is_cbz(insn) || aarch64_insn_is_cbnz(insn) ||
1168 aarch64_insn_is_bcond(insn)) {
1169 imm = aarch64_insn_decode_immediate(AARCH64_INSN_IMM_19, insn);
1170 return (imm << 13) >> 11;
1171 }
1172
1173 if (aarch64_insn_is_tbz(insn) || aarch64_insn_is_tbnz(insn)) {
1174 imm = aarch64_insn_decode_immediate(AARCH64_INSN_IMM_14, insn);
1175 return (imm << 18) >> 16;
1176 }
1177
1178 /* Unhandled instruction */
1179 BUG();
1180 }
1181
1182 /*
1183 * Encode the displacement of a branch in the imm field and return the
1184 * updated instruction.
1185 */
aarch64_set_branch_offset(u32 insn,s32 offset)1186 u32 aarch64_set_branch_offset(u32 insn, s32 offset)
1187 {
1188 if (aarch64_insn_is_b(insn) || aarch64_insn_is_bl(insn))
1189 return aarch64_insn_encode_immediate(AARCH64_INSN_IMM_26, insn,
1190 offset >> 2);
1191
1192 if (aarch64_insn_is_cbz(insn) || aarch64_insn_is_cbnz(insn) ||
1193 aarch64_insn_is_bcond(insn))
1194 return aarch64_insn_encode_immediate(AARCH64_INSN_IMM_19, insn,
1195 offset >> 2);
1196
1197 if (aarch64_insn_is_tbz(insn) || aarch64_insn_is_tbnz(insn))
1198 return aarch64_insn_encode_immediate(AARCH64_INSN_IMM_14, insn,
1199 offset >> 2);
1200
1201 /* Unhandled instruction */
1202 BUG();
1203 }
1204
aarch64_insn_adrp_get_offset(u32 insn)1205 s32 aarch64_insn_adrp_get_offset(u32 insn)
1206 {
1207 BUG_ON(!aarch64_insn_is_adrp(insn));
1208 return aarch64_insn_decode_immediate(AARCH64_INSN_IMM_ADR, insn) << 12;
1209 }
1210
aarch64_insn_adrp_set_offset(u32 insn,s32 offset)1211 u32 aarch64_insn_adrp_set_offset(u32 insn, s32 offset)
1212 {
1213 BUG_ON(!aarch64_insn_is_adrp(insn));
1214 return aarch64_insn_encode_immediate(AARCH64_INSN_IMM_ADR, insn,
1215 offset >> 12);
1216 }
1217
1218 /*
1219 * Extract the Op/CR data from a msr/mrs instruction.
1220 */
aarch64_insn_extract_system_reg(u32 insn)1221 u32 aarch64_insn_extract_system_reg(u32 insn)
1222 {
1223 return (insn & 0x1FFFE0) >> 5;
1224 }
1225
aarch32_insn_is_wide(u32 insn)1226 bool aarch32_insn_is_wide(u32 insn)
1227 {
1228 return insn >= 0xe800;
1229 }
1230
1231 /*
1232 * Macros/defines for extracting register numbers from instruction.
1233 */
aarch32_insn_extract_reg_num(u32 insn,int offset)1234 u32 aarch32_insn_extract_reg_num(u32 insn, int offset)
1235 {
1236 return (insn & (0xf << offset)) >> offset;
1237 }
1238
1239 #define OPC2_MASK 0x7
1240 #define OPC2_OFFSET 5
aarch32_insn_mcr_extract_opc2(u32 insn)1241 u32 aarch32_insn_mcr_extract_opc2(u32 insn)
1242 {
1243 return (insn & (OPC2_MASK << OPC2_OFFSET)) >> OPC2_OFFSET;
1244 }
1245
1246 #define CRM_MASK 0xf
aarch32_insn_mcr_extract_crm(u32 insn)1247 u32 aarch32_insn_mcr_extract_crm(u32 insn)
1248 {
1249 return insn & CRM_MASK;
1250 }
1251
__check_eq(unsigned long pstate)1252 static bool __kprobes __check_eq(unsigned long pstate)
1253 {
1254 return (pstate & PSR_Z_BIT) != 0;
1255 }
1256
__check_ne(unsigned long pstate)1257 static bool __kprobes __check_ne(unsigned long pstate)
1258 {
1259 return (pstate & PSR_Z_BIT) == 0;
1260 }
1261
__check_cs(unsigned long pstate)1262 static bool __kprobes __check_cs(unsigned long pstate)
1263 {
1264 return (pstate & PSR_C_BIT) != 0;
1265 }
1266
__check_cc(unsigned long pstate)1267 static bool __kprobes __check_cc(unsigned long pstate)
1268 {
1269 return (pstate & PSR_C_BIT) == 0;
1270 }
1271
__check_mi(unsigned long pstate)1272 static bool __kprobes __check_mi(unsigned long pstate)
1273 {
1274 return (pstate & PSR_N_BIT) != 0;
1275 }
1276
__check_pl(unsigned long pstate)1277 static bool __kprobes __check_pl(unsigned long pstate)
1278 {
1279 return (pstate & PSR_N_BIT) == 0;
1280 }
1281
__check_vs(unsigned long pstate)1282 static bool __kprobes __check_vs(unsigned long pstate)
1283 {
1284 return (pstate & PSR_V_BIT) != 0;
1285 }
1286
__check_vc(unsigned long pstate)1287 static bool __kprobes __check_vc(unsigned long pstate)
1288 {
1289 return (pstate & PSR_V_BIT) == 0;
1290 }
1291
__check_hi(unsigned long pstate)1292 static bool __kprobes __check_hi(unsigned long pstate)
1293 {
1294 pstate &= ~(pstate >> 1); /* PSR_C_BIT &= ~PSR_Z_BIT */
1295 return (pstate & PSR_C_BIT) != 0;
1296 }
1297
__check_ls(unsigned long pstate)1298 static bool __kprobes __check_ls(unsigned long pstate)
1299 {
1300 pstate &= ~(pstate >> 1); /* PSR_C_BIT &= ~PSR_Z_BIT */
1301 return (pstate & PSR_C_BIT) == 0;
1302 }
1303
__check_ge(unsigned long pstate)1304 static bool __kprobes __check_ge(unsigned long pstate)
1305 {
1306 pstate ^= (pstate << 3); /* PSR_N_BIT ^= PSR_V_BIT */
1307 return (pstate & PSR_N_BIT) == 0;
1308 }
1309
__check_lt(unsigned long pstate)1310 static bool __kprobes __check_lt(unsigned long pstate)
1311 {
1312 pstate ^= (pstate << 3); /* PSR_N_BIT ^= PSR_V_BIT */
1313 return (pstate & PSR_N_BIT) != 0;
1314 }
1315
__check_gt(unsigned long pstate)1316 static bool __kprobes __check_gt(unsigned long pstate)
1317 {
1318 /*PSR_N_BIT ^= PSR_V_BIT */
1319 unsigned long temp = pstate ^ (pstate << 3);
1320
1321 temp |= (pstate << 1); /*PSR_N_BIT |= PSR_Z_BIT */
1322 return (temp & PSR_N_BIT) == 0;
1323 }
1324
__check_le(unsigned long pstate)1325 static bool __kprobes __check_le(unsigned long pstate)
1326 {
1327 /*PSR_N_BIT ^= PSR_V_BIT */
1328 unsigned long temp = pstate ^ (pstate << 3);
1329
1330 temp |= (pstate << 1); /*PSR_N_BIT |= PSR_Z_BIT */
1331 return (temp & PSR_N_BIT) != 0;
1332 }
1333
__check_al(unsigned long pstate)1334 static bool __kprobes __check_al(unsigned long pstate)
1335 {
1336 return true;
1337 }
1338
1339 /*
1340 * Note that the ARMv8 ARM calls condition code 0b1111 "nv", but states that
1341 * it behaves identically to 0b1110 ("al").
1342 */
1343 pstate_check_t * const aarch32_opcode_cond_checks[16] = {
1344 __check_eq, __check_ne, __check_cs, __check_cc,
1345 __check_mi, __check_pl, __check_vs, __check_vc,
1346 __check_hi, __check_ls, __check_ge, __check_lt,
1347 __check_gt, __check_le, __check_al, __check_al
1348 };
1349