xref: /openbmc/qemu/accel/tcg/user-exec.c (revision 59e96ac6)
1 /*
2  *  User emulator execution
3  *
4  *  Copyright (c) 2003-2005 Fabrice Bellard
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * This library 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 GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18  */
19 #include "qemu/osdep.h"
20 #include "cpu.h"
21 #include "disas/disas.h"
22 #include "exec/exec-all.h"
23 #include "tcg.h"
24 #include "qemu/bitops.h"
25 #include "exec/cpu_ldst.h"
26 #include "translate-all.h"
27 #include "exec/helper-proto.h"
28 #include "qemu/atomic128.h"
29 
30 #undef EAX
31 #undef ECX
32 #undef EDX
33 #undef EBX
34 #undef ESP
35 #undef EBP
36 #undef ESI
37 #undef EDI
38 #undef EIP
39 #ifdef __linux__
40 #include <sys/ucontext.h>
41 #endif
42 
43 __thread uintptr_t helper_retaddr;
44 
45 //#define DEBUG_SIGNAL
46 
47 /* exit the current TB from a signal handler. The host registers are
48    restored in a state compatible with the CPU emulator
49  */
50 static void cpu_exit_tb_from_sighandler(CPUState *cpu, sigset_t *old_set)
51 {
52     /* XXX: use siglongjmp ? */
53     sigprocmask(SIG_SETMASK, old_set, NULL);
54     cpu_loop_exit_noexc(cpu);
55 }
56 
57 /* 'pc' is the host PC at which the exception was raised. 'address' is
58    the effective address of the memory exception. 'is_write' is 1 if a
59    write caused the exception and otherwise 0'. 'old_set' is the
60    signal set which should be restored */
61 static inline int handle_cpu_signal(uintptr_t pc, siginfo_t *info,
62                                     int is_write, sigset_t *old_set)
63 {
64     CPUState *cpu = current_cpu;
65     CPUClass *cc;
66     unsigned long address = (unsigned long)info->si_addr;
67     MMUAccessType access_type = is_write ? MMU_DATA_STORE : MMU_DATA_LOAD;
68 
69     switch (helper_retaddr) {
70     default:
71         /*
72          * Fault during host memory operation within a helper function.
73          * The helper's host return address, saved here, gives us a
74          * pointer into the generated code that will unwind to the
75          * correct guest pc.
76          */
77         pc = helper_retaddr;
78         break;
79 
80     case 0:
81         /*
82          * Fault during host memory operation within generated code.
83          * (Or, a unrelated bug within qemu, but we can't tell from here).
84          *
85          * We take the host pc from the signal frame.  However, we cannot
86          * use that value directly.  Within cpu_restore_state_from_tb, we
87          * assume PC comes from GETPC(), as used by the helper functions,
88          * so we adjust the address by -GETPC_ADJ to form an address that
89          * is within the call insn, so that the address does not accidentially
90          * match the beginning of the next guest insn.  However, when the
91          * pc comes from the signal frame it points to the actual faulting
92          * host memory insn and not the return from a call insn.
93          *
94          * Therefore, adjust to compensate for what will be done later
95          * by cpu_restore_state_from_tb.
96          */
97         pc += GETPC_ADJ;
98         break;
99 
100     case 1:
101         /*
102          * Fault during host read for translation, or loosely, "execution".
103          *
104          * The guest pc is already pointing to the start of the TB for which
105          * code is being generated.  If the guest translator manages the
106          * page crossings correctly, this is exactly the correct address
107          * (and if the translator doesn't handle page boundaries correctly
108          * there's little we can do about that here).  Therefore, do not
109          * trigger the unwinder.
110          *
111          * Like tb_gen_code, release the memory lock before cpu_loop_exit.
112          */
113         pc = 0;
114         access_type = MMU_INST_FETCH;
115         mmap_unlock();
116         break;
117     }
118 
119     /* For synchronous signals we expect to be coming from the vCPU
120      * thread (so current_cpu should be valid) and either from running
121      * code or during translation which can fault as we cross pages.
122      *
123      * If neither is true then something has gone wrong and we should
124      * abort rather than try and restart the vCPU execution.
125      */
126     if (!cpu || !cpu->running) {
127         printf("qemu:%s received signal outside vCPU context @ pc=0x%"
128                PRIxPTR "\n",  __func__, pc);
129         abort();
130     }
131 
132 #if defined(DEBUG_SIGNAL)
133     printf("qemu: SIGSEGV pc=0x%08lx address=%08lx w=%d oldset=0x%08lx\n",
134            pc, address, is_write, *(unsigned long *)old_set);
135 #endif
136     /* XXX: locking issue */
137     /* Note that it is important that we don't call page_unprotect() unless
138      * this is really a "write to nonwriteable page" fault, because
139      * page_unprotect() assumes that if it is called for an access to
140      * a page that's writeable this means we had two threads racing and
141      * another thread got there first and already made the page writeable;
142      * so we will retry the access. If we were to call page_unprotect()
143      * for some other kind of fault that should really be passed to the
144      * guest, we'd end up in an infinite loop of retrying the faulting
145      * access.
146      */
147     if (is_write && info->si_signo == SIGSEGV && info->si_code == SEGV_ACCERR &&
148         h2g_valid(address)) {
149         switch (page_unprotect(h2g(address), pc)) {
150         case 0:
151             /* Fault not caused by a page marked unwritable to protect
152              * cached translations, must be the guest binary's problem.
153              */
154             break;
155         case 1:
156             /* Fault caused by protection of cached translation; TBs
157              * invalidated, so resume execution.  Retain helper_retaddr
158              * for a possible second fault.
159              */
160             return 1;
161         case 2:
162             /* Fault caused by protection of cached translation, and the
163              * currently executing TB was modified and must be exited
164              * immediately.  Clear helper_retaddr for next execution.
165              */
166             clear_helper_retaddr();
167             cpu_exit_tb_from_sighandler(cpu, old_set);
168             /* NORETURN */
169 
170         default:
171             g_assert_not_reached();
172         }
173     }
174 
175     /* Convert forcefully to guest address space, invalid addresses
176        are still valid segv ones */
177     address = h2g_nocheck(address);
178 
179     /*
180      * There is no way the target can handle this other than raising
181      * an exception.  Undo signal and retaddr state prior to longjmp.
182      */
183     sigprocmask(SIG_SETMASK, old_set, NULL);
184     clear_helper_retaddr();
185 
186     cc = CPU_GET_CLASS(cpu);
187     cc->tlb_fill(cpu, address, 0, access_type, MMU_USER_IDX, false, pc);
188     g_assert_not_reached();
189 }
190 
191 void probe_write(CPUArchState *env, target_ulong addr, int size, int mmu_idx,
192                  uintptr_t retaddr)
193 {
194     if (!guest_addr_valid(addr) ||
195         page_check_range(addr, size, PAGE_WRITE) < 0) {
196         CPUState *cpu = env_cpu(env);
197         CPUClass *cc = CPU_GET_CLASS(cpu);
198 
199         cc->tlb_fill(cpu, addr, size, MMU_DATA_STORE, MMU_USER_IDX, false,
200                      retaddr);
201         g_assert_not_reached();
202     }
203 }
204 
205 #if defined(__i386__)
206 
207 #if defined(__NetBSD__)
208 #include <ucontext.h>
209 
210 #define EIP_sig(context)     ((context)->uc_mcontext.__gregs[_REG_EIP])
211 #define TRAP_sig(context)    ((context)->uc_mcontext.__gregs[_REG_TRAPNO])
212 #define ERROR_sig(context)   ((context)->uc_mcontext.__gregs[_REG_ERR])
213 #define MASK_sig(context)    ((context)->uc_sigmask)
214 #elif defined(__FreeBSD__) || defined(__DragonFly__)
215 #include <ucontext.h>
216 
217 #define EIP_sig(context)  (*((unsigned long *)&(context)->uc_mcontext.mc_eip))
218 #define TRAP_sig(context)    ((context)->uc_mcontext.mc_trapno)
219 #define ERROR_sig(context)   ((context)->uc_mcontext.mc_err)
220 #define MASK_sig(context)    ((context)->uc_sigmask)
221 #elif defined(__OpenBSD__)
222 #define EIP_sig(context)     ((context)->sc_eip)
223 #define TRAP_sig(context)    ((context)->sc_trapno)
224 #define ERROR_sig(context)   ((context)->sc_err)
225 #define MASK_sig(context)    ((context)->sc_mask)
226 #else
227 #define EIP_sig(context)     ((context)->uc_mcontext.gregs[REG_EIP])
228 #define TRAP_sig(context)    ((context)->uc_mcontext.gregs[REG_TRAPNO])
229 #define ERROR_sig(context)   ((context)->uc_mcontext.gregs[REG_ERR])
230 #define MASK_sig(context)    ((context)->uc_sigmask)
231 #endif
232 
233 int cpu_signal_handler(int host_signum, void *pinfo,
234                        void *puc)
235 {
236     siginfo_t *info = pinfo;
237 #if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__DragonFly__)
238     ucontext_t *uc = puc;
239 #elif defined(__OpenBSD__)
240     struct sigcontext *uc = puc;
241 #else
242     ucontext_t *uc = puc;
243 #endif
244     unsigned long pc;
245     int trapno;
246 
247 #ifndef REG_EIP
248 /* for glibc 2.1 */
249 #define REG_EIP    EIP
250 #define REG_ERR    ERR
251 #define REG_TRAPNO TRAPNO
252 #endif
253     pc = EIP_sig(uc);
254     trapno = TRAP_sig(uc);
255     return handle_cpu_signal(pc, info,
256                              trapno == 0xe ? (ERROR_sig(uc) >> 1) & 1 : 0,
257                              &MASK_sig(uc));
258 }
259 
260 #elif defined(__x86_64__)
261 
262 #ifdef __NetBSD__
263 #define PC_sig(context)       _UC_MACHINE_PC(context)
264 #define TRAP_sig(context)     ((context)->uc_mcontext.__gregs[_REG_TRAPNO])
265 #define ERROR_sig(context)    ((context)->uc_mcontext.__gregs[_REG_ERR])
266 #define MASK_sig(context)     ((context)->uc_sigmask)
267 #elif defined(__OpenBSD__)
268 #define PC_sig(context)       ((context)->sc_rip)
269 #define TRAP_sig(context)     ((context)->sc_trapno)
270 #define ERROR_sig(context)    ((context)->sc_err)
271 #define MASK_sig(context)     ((context)->sc_mask)
272 #elif defined(__FreeBSD__) || defined(__DragonFly__)
273 #include <ucontext.h>
274 
275 #define PC_sig(context)  (*((unsigned long *)&(context)->uc_mcontext.mc_rip))
276 #define TRAP_sig(context)     ((context)->uc_mcontext.mc_trapno)
277 #define ERROR_sig(context)    ((context)->uc_mcontext.mc_err)
278 #define MASK_sig(context)     ((context)->uc_sigmask)
279 #else
280 #define PC_sig(context)       ((context)->uc_mcontext.gregs[REG_RIP])
281 #define TRAP_sig(context)     ((context)->uc_mcontext.gregs[REG_TRAPNO])
282 #define ERROR_sig(context)    ((context)->uc_mcontext.gregs[REG_ERR])
283 #define MASK_sig(context)     ((context)->uc_sigmask)
284 #endif
285 
286 int cpu_signal_handler(int host_signum, void *pinfo,
287                        void *puc)
288 {
289     siginfo_t *info = pinfo;
290     unsigned long pc;
291 #if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__DragonFly__)
292     ucontext_t *uc = puc;
293 #elif defined(__OpenBSD__)
294     struct sigcontext *uc = puc;
295 #else
296     ucontext_t *uc = puc;
297 #endif
298 
299     pc = PC_sig(uc);
300     return handle_cpu_signal(pc, info,
301                              TRAP_sig(uc) == 0xe ? (ERROR_sig(uc) >> 1) & 1 : 0,
302                              &MASK_sig(uc));
303 }
304 
305 #elif defined(_ARCH_PPC)
306 
307 /***********************************************************************
308  * signal context platform-specific definitions
309  * From Wine
310  */
311 #ifdef linux
312 /* All Registers access - only for local access */
313 #define REG_sig(reg_name, context)              \
314     ((context)->uc_mcontext.regs->reg_name)
315 /* Gpr Registers access  */
316 #define GPR_sig(reg_num, context)              REG_sig(gpr[reg_num], context)
317 /* Program counter */
318 #define IAR_sig(context)                       REG_sig(nip, context)
319 /* Machine State Register (Supervisor) */
320 #define MSR_sig(context)                       REG_sig(msr, context)
321 /* Count register */
322 #define CTR_sig(context)                       REG_sig(ctr, context)
323 /* User's integer exception register */
324 #define XER_sig(context)                       REG_sig(xer, context)
325 /* Link register */
326 #define LR_sig(context)                        REG_sig(link, context)
327 /* Condition register */
328 #define CR_sig(context)                        REG_sig(ccr, context)
329 
330 /* Float Registers access  */
331 #define FLOAT_sig(reg_num, context)                                     \
332     (((double *)((char *)((context)->uc_mcontext.regs + 48 * 4)))[reg_num])
333 #define FPSCR_sig(context) \
334     (*(int *)((char *)((context)->uc_mcontext.regs + (48 + 32 * 2) * 4)))
335 /* Exception Registers access */
336 #define DAR_sig(context)                       REG_sig(dar, context)
337 #define DSISR_sig(context)                     REG_sig(dsisr, context)
338 #define TRAP_sig(context)                      REG_sig(trap, context)
339 #endif /* linux */
340 
341 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
342 #include <ucontext.h>
343 #define IAR_sig(context)               ((context)->uc_mcontext.mc_srr0)
344 #define MSR_sig(context)               ((context)->uc_mcontext.mc_srr1)
345 #define CTR_sig(context)               ((context)->uc_mcontext.mc_ctr)
346 #define XER_sig(context)               ((context)->uc_mcontext.mc_xer)
347 #define LR_sig(context)                ((context)->uc_mcontext.mc_lr)
348 #define CR_sig(context)                ((context)->uc_mcontext.mc_cr)
349 /* Exception Registers access */
350 #define DAR_sig(context)               ((context)->uc_mcontext.mc_dar)
351 #define DSISR_sig(context)             ((context)->uc_mcontext.mc_dsisr)
352 #define TRAP_sig(context)              ((context)->uc_mcontext.mc_exc)
353 #endif /* __FreeBSD__|| __FreeBSD_kernel__ */
354 
355 int cpu_signal_handler(int host_signum, void *pinfo,
356                        void *puc)
357 {
358     siginfo_t *info = pinfo;
359 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
360     ucontext_t *uc = puc;
361 #else
362     ucontext_t *uc = puc;
363 #endif
364     unsigned long pc;
365     int is_write;
366 
367     pc = IAR_sig(uc);
368     is_write = 0;
369 #if 0
370     /* ppc 4xx case */
371     if (DSISR_sig(uc) & 0x00800000) {
372         is_write = 1;
373     }
374 #else
375     if (TRAP_sig(uc) != 0x400 && (DSISR_sig(uc) & 0x02000000)) {
376         is_write = 1;
377     }
378 #endif
379     return handle_cpu_signal(pc, info, is_write, &uc->uc_sigmask);
380 }
381 
382 #elif defined(__alpha__)
383 
384 int cpu_signal_handler(int host_signum, void *pinfo,
385                            void *puc)
386 {
387     siginfo_t *info = pinfo;
388     ucontext_t *uc = puc;
389     uint32_t *pc = uc->uc_mcontext.sc_pc;
390     uint32_t insn = *pc;
391     int is_write = 0;
392 
393     /* XXX: need kernel patch to get write flag faster */
394     switch (insn >> 26) {
395     case 0x0d: /* stw */
396     case 0x0e: /* stb */
397     case 0x0f: /* stq_u */
398     case 0x24: /* stf */
399     case 0x25: /* stg */
400     case 0x26: /* sts */
401     case 0x27: /* stt */
402     case 0x2c: /* stl */
403     case 0x2d: /* stq */
404     case 0x2e: /* stl_c */
405     case 0x2f: /* stq_c */
406         is_write = 1;
407     }
408 
409     return handle_cpu_signal(pc, info, is_write, &uc->uc_sigmask);
410 }
411 #elif defined(__sparc__)
412 
413 int cpu_signal_handler(int host_signum, void *pinfo,
414                        void *puc)
415 {
416     siginfo_t *info = pinfo;
417     int is_write;
418     uint32_t insn;
419 #if !defined(__arch64__) || defined(CONFIG_SOLARIS)
420     uint32_t *regs = (uint32_t *)(info + 1);
421     void *sigmask = (regs + 20);
422     /* XXX: is there a standard glibc define ? */
423     unsigned long pc = regs[1];
424 #else
425 #ifdef __linux__
426     struct sigcontext *sc = puc;
427     unsigned long pc = sc->sigc_regs.tpc;
428     void *sigmask = (void *)sc->sigc_mask;
429 #elif defined(__OpenBSD__)
430     struct sigcontext *uc = puc;
431     unsigned long pc = uc->sc_pc;
432     void *sigmask = (void *)(long)uc->sc_mask;
433 #elif defined(__NetBSD__)
434     ucontext_t *uc = puc;
435     unsigned long pc = _UC_MACHINE_PC(uc);
436     void *sigmask = (void *)&uc->uc_sigmask;
437 #endif
438 #endif
439 
440     /* XXX: need kernel patch to get write flag faster */
441     is_write = 0;
442     insn = *(uint32_t *)pc;
443     if ((insn >> 30) == 3) {
444         switch ((insn >> 19) & 0x3f) {
445         case 0x05: /* stb */
446         case 0x15: /* stba */
447         case 0x06: /* sth */
448         case 0x16: /* stha */
449         case 0x04: /* st */
450         case 0x14: /* sta */
451         case 0x07: /* std */
452         case 0x17: /* stda */
453         case 0x0e: /* stx */
454         case 0x1e: /* stxa */
455         case 0x24: /* stf */
456         case 0x34: /* stfa */
457         case 0x27: /* stdf */
458         case 0x37: /* stdfa */
459         case 0x26: /* stqf */
460         case 0x36: /* stqfa */
461         case 0x25: /* stfsr */
462         case 0x3c: /* casa */
463         case 0x3e: /* casxa */
464             is_write = 1;
465             break;
466         }
467     }
468     return handle_cpu_signal(pc, info, is_write, sigmask);
469 }
470 
471 #elif defined(__arm__)
472 
473 #if defined(__NetBSD__)
474 #include <ucontext.h>
475 #endif
476 
477 int cpu_signal_handler(int host_signum, void *pinfo,
478                        void *puc)
479 {
480     siginfo_t *info = pinfo;
481 #if defined(__NetBSD__)
482     ucontext_t *uc = puc;
483 #else
484     ucontext_t *uc = puc;
485 #endif
486     unsigned long pc;
487     int is_write;
488 
489 #if defined(__NetBSD__)
490     pc = uc->uc_mcontext.__gregs[_REG_R15];
491 #elif defined(__GLIBC__) && (__GLIBC__ < 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ <= 3))
492     pc = uc->uc_mcontext.gregs[R15];
493 #else
494     pc = uc->uc_mcontext.arm_pc;
495 #endif
496 
497     /* error_code is the FSR value, in which bit 11 is WnR (assuming a v6 or
498      * later processor; on v5 we will always report this as a read).
499      */
500     is_write = extract32(uc->uc_mcontext.error_code, 11, 1);
501     return handle_cpu_signal(pc, info, is_write, &uc->uc_sigmask);
502 }
503 
504 #elif defined(__aarch64__)
505 
506 #ifndef ESR_MAGIC
507 /* Pre-3.16 kernel headers don't have these, so provide fallback definitions */
508 #define ESR_MAGIC 0x45535201
509 struct esr_context {
510     struct _aarch64_ctx head;
511     uint64_t esr;
512 };
513 #endif
514 
515 static inline struct _aarch64_ctx *first_ctx(ucontext_t *uc)
516 {
517     return (struct _aarch64_ctx *)&uc->uc_mcontext.__reserved;
518 }
519 
520 static inline struct _aarch64_ctx *next_ctx(struct _aarch64_ctx *hdr)
521 {
522     return (struct _aarch64_ctx *)((char *)hdr + hdr->size);
523 }
524 
525 int cpu_signal_handler(int host_signum, void *pinfo, void *puc)
526 {
527     siginfo_t *info = pinfo;
528     ucontext_t *uc = puc;
529     uintptr_t pc = uc->uc_mcontext.pc;
530     bool is_write;
531     struct _aarch64_ctx *hdr;
532     struct esr_context const *esrctx = NULL;
533 
534     /* Find the esr_context, which has the WnR bit in it */
535     for (hdr = first_ctx(uc); hdr->magic; hdr = next_ctx(hdr)) {
536         if (hdr->magic == ESR_MAGIC) {
537             esrctx = (struct esr_context const *)hdr;
538             break;
539         }
540     }
541 
542     if (esrctx) {
543         /* For data aborts ESR.EC is 0b10010x: then bit 6 is the WnR bit */
544         uint64_t esr = esrctx->esr;
545         is_write = extract32(esr, 27, 5) == 0x12 && extract32(esr, 6, 1) == 1;
546     } else {
547         /*
548          * Fall back to parsing instructions; will only be needed
549          * for really ancient (pre-3.16) kernels.
550          */
551         uint32_t insn = *(uint32_t *)pc;
552 
553         is_write = ((insn & 0xbfff0000) == 0x0c000000   /* C3.3.1 */
554                     || (insn & 0xbfe00000) == 0x0c800000   /* C3.3.2 */
555                     || (insn & 0xbfdf0000) == 0x0d000000   /* C3.3.3 */
556                     || (insn & 0xbfc00000) == 0x0d800000   /* C3.3.4 */
557                     || (insn & 0x3f400000) == 0x08000000   /* C3.3.6 */
558                     || (insn & 0x3bc00000) == 0x39000000   /* C3.3.13 */
559                     || (insn & 0x3fc00000) == 0x3d800000   /* ... 128bit */
560                     /* Ignore bits 10, 11 & 21, controlling indexing.  */
561                     || (insn & 0x3bc00000) == 0x38000000   /* C3.3.8-12 */
562                     || (insn & 0x3fe00000) == 0x3c800000   /* ... 128bit */
563                     /* Ignore bits 23 & 24, controlling indexing.  */
564                     || (insn & 0x3a400000) == 0x28000000); /* C3.3.7,14-16 */
565     }
566     return handle_cpu_signal(pc, info, is_write, &uc->uc_sigmask);
567 }
568 
569 #elif defined(__s390__)
570 
571 int cpu_signal_handler(int host_signum, void *pinfo,
572                        void *puc)
573 {
574     siginfo_t *info = pinfo;
575     ucontext_t *uc = puc;
576     unsigned long pc;
577     uint16_t *pinsn;
578     int is_write = 0;
579 
580     pc = uc->uc_mcontext.psw.addr;
581 
582     /* ??? On linux, the non-rt signal handler has 4 (!) arguments instead
583        of the normal 2 arguments.  The 3rd argument contains the "int_code"
584        from the hardware which does in fact contain the is_write value.
585        The rt signal handler, as far as I can tell, does not give this value
586        at all.  Not that we could get to it from here even if it were.  */
587     /* ??? This is not even close to complete, since it ignores all
588        of the read-modify-write instructions.  */
589     pinsn = (uint16_t *)pc;
590     switch (pinsn[0] >> 8) {
591     case 0x50: /* ST */
592     case 0x42: /* STC */
593     case 0x40: /* STH */
594         is_write = 1;
595         break;
596     case 0xc4: /* RIL format insns */
597         switch (pinsn[0] & 0xf) {
598         case 0xf: /* STRL */
599         case 0xb: /* STGRL */
600         case 0x7: /* STHRL */
601             is_write = 1;
602         }
603         break;
604     case 0xe3: /* RXY format insns */
605         switch (pinsn[2] & 0xff) {
606         case 0x50: /* STY */
607         case 0x24: /* STG */
608         case 0x72: /* STCY */
609         case 0x70: /* STHY */
610         case 0x8e: /* STPQ */
611         case 0x3f: /* STRVH */
612         case 0x3e: /* STRV */
613         case 0x2f: /* STRVG */
614             is_write = 1;
615         }
616         break;
617     }
618     return handle_cpu_signal(pc, info, is_write, &uc->uc_sigmask);
619 }
620 
621 #elif defined(__mips__)
622 
623 int cpu_signal_handler(int host_signum, void *pinfo,
624                        void *puc)
625 {
626     siginfo_t *info = pinfo;
627     ucontext_t *uc = puc;
628     greg_t pc = uc->uc_mcontext.pc;
629     int is_write;
630 
631     /* XXX: compute is_write */
632     is_write = 0;
633     return handle_cpu_signal(pc, info, is_write, &uc->uc_sigmask);
634 }
635 
636 #elif defined(__riscv)
637 
638 int cpu_signal_handler(int host_signum, void *pinfo,
639                        void *puc)
640 {
641     siginfo_t *info = pinfo;
642     ucontext_t *uc = puc;
643     greg_t pc = uc->uc_mcontext.__gregs[REG_PC];
644     uint32_t insn = *(uint32_t *)pc;
645     int is_write = 0;
646 
647     /* Detect store by reading the instruction at the program
648        counter. Note: we currently only generate 32-bit
649        instructions so we thus only detect 32-bit stores */
650     switch (((insn >> 0) & 0b11)) {
651     case 3:
652         switch (((insn >> 2) & 0b11111)) {
653         case 8:
654             switch (((insn >> 12) & 0b111)) {
655             case 0: /* sb */
656             case 1: /* sh */
657             case 2: /* sw */
658             case 3: /* sd */
659             case 4: /* sq */
660                 is_write = 1;
661                 break;
662             default:
663                 break;
664             }
665             break;
666         case 9:
667             switch (((insn >> 12) & 0b111)) {
668             case 2: /* fsw */
669             case 3: /* fsd */
670             case 4: /* fsq */
671                 is_write = 1;
672                 break;
673             default:
674                 break;
675             }
676             break;
677         default:
678             break;
679         }
680     }
681 
682     /* Check for compressed instructions */
683     switch (((insn >> 13) & 0b111)) {
684     case 7:
685         switch (insn & 0b11) {
686         case 0: /*c.sd */
687         case 2: /* c.sdsp */
688             is_write = 1;
689             break;
690         default:
691             break;
692         }
693         break;
694     case 6:
695         switch (insn & 0b11) {
696         case 0: /* c.sw */
697         case 3: /* c.swsp */
698             is_write = 1;
699             break;
700         default:
701             break;
702         }
703         break;
704     default:
705         break;
706     }
707 
708     return handle_cpu_signal(pc, info, is_write, &uc->uc_sigmask);
709 }
710 
711 #else
712 
713 #error host CPU specific signal handler needed
714 
715 #endif
716 
717 /* The softmmu versions of these helpers are in cputlb.c.  */
718 
719 /* Do not allow unaligned operations to proceed.  Return the host address.  */
720 static void *atomic_mmu_lookup(CPUArchState *env, target_ulong addr,
721                                int size, uintptr_t retaddr)
722 {
723     /* Enforce qemu required alignment.  */
724     if (unlikely(addr & (size - 1))) {
725         cpu_loop_exit_atomic(env_cpu(env), retaddr);
726     }
727     void *ret = g2h(addr);
728     set_helper_retaddr(retaddr);
729     return ret;
730 }
731 
732 /* Macro to call the above, with local variables from the use context.  */
733 #define ATOMIC_MMU_DECLS do {} while (0)
734 #define ATOMIC_MMU_LOOKUP  atomic_mmu_lookup(env, addr, DATA_SIZE, GETPC())
735 #define ATOMIC_MMU_CLEANUP do { clear_helper_retaddr(); } while (0)
736 
737 #define ATOMIC_NAME(X)   HELPER(glue(glue(atomic_ ## X, SUFFIX), END))
738 #define EXTRA_ARGS
739 
740 #define DATA_SIZE 1
741 #include "atomic_template.h"
742 
743 #define DATA_SIZE 2
744 #include "atomic_template.h"
745 
746 #define DATA_SIZE 4
747 #include "atomic_template.h"
748 
749 #ifdef CONFIG_ATOMIC64
750 #define DATA_SIZE 8
751 #include "atomic_template.h"
752 #endif
753 
754 /* The following is only callable from other helpers, and matches up
755    with the softmmu version.  */
756 
757 #if HAVE_ATOMIC128 || HAVE_CMPXCHG128
758 
759 #undef EXTRA_ARGS
760 #undef ATOMIC_NAME
761 #undef ATOMIC_MMU_LOOKUP
762 
763 #define EXTRA_ARGS     , TCGMemOpIdx oi, uintptr_t retaddr
764 #define ATOMIC_NAME(X) \
765     HELPER(glue(glue(glue(atomic_ ## X, SUFFIX), END), _mmu))
766 #define ATOMIC_MMU_LOOKUP  atomic_mmu_lookup(env, addr, DATA_SIZE, retaddr)
767 
768 #define DATA_SIZE 16
769 #include "atomic_template.h"
770 #endif
771