xref: /openbmc/qemu/linux-user/aarch64/signal.c (revision ff0102f6)
1 /*
2  *  Emulation of Linux signals
3  *
4  *  Copyright (c) 2003 Fabrice Bellard
5  *
6  *  This program is free software; you can redistribute it and/or modify
7  *  it under the terms of the GNU General Public License as published by
8  *  the Free Software Foundation; either version 2 of the License, or
9  *  (at your option) any later version.
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 "qemu/osdep.h"
20 #include "qemu.h"
21 #include "user-internals.h"
22 #include "signal-common.h"
23 #include "linux-user/trace.h"
24 
25 struct target_sigcontext {
26     uint64_t fault_address;
27     /* AArch64 registers */
28     uint64_t regs[31];
29     uint64_t sp;
30     uint64_t pc;
31     uint64_t pstate;
32     /* 4K reserved for FP/SIMD state and future expansion */
33     char __reserved[4096] __attribute__((__aligned__(16)));
34 };
35 
36 struct target_ucontext {
37     abi_ulong tuc_flags;
38     abi_ulong tuc_link;
39     target_stack_t tuc_stack;
40     target_sigset_t tuc_sigmask;
41     /* glibc uses a 1024-bit sigset_t */
42     char __unused[1024 / 8 - sizeof(target_sigset_t)];
43     /* last for future expansion */
44     struct target_sigcontext tuc_mcontext;
45 };
46 
47 /*
48  * Header to be used at the beginning of structures extending the user
49  * context. Such structures must be placed after the rt_sigframe on the stack
50  * and be 16-byte aligned. The last structure must be a dummy one with the
51  * magic and size set to 0.
52  */
53 struct target_aarch64_ctx {
54     uint32_t magic;
55     uint32_t size;
56 };
57 
58 #define TARGET_FPSIMD_MAGIC 0x46508001
59 
60 struct target_fpsimd_context {
61     struct target_aarch64_ctx head;
62     uint32_t fpsr;
63     uint32_t fpcr;
64     uint64_t vregs[32 * 2]; /* really uint128_t vregs[32] */
65 };
66 
67 #define TARGET_EXTRA_MAGIC  0x45585401
68 
69 struct target_extra_context {
70     struct target_aarch64_ctx head;
71     uint64_t datap; /* 16-byte aligned pointer to extra space cast to __u64 */
72     uint32_t size; /* size in bytes of the extra space */
73     uint32_t reserved[3];
74 };
75 
76 #define TARGET_SVE_MAGIC    0x53564501
77 
78 struct target_sve_context {
79     struct target_aarch64_ctx head;
80     uint16_t vl;
81     uint16_t flags;
82     uint16_t reserved[2];
83     /* The actual SVE data immediately follows.  It is laid out
84      * according to TARGET_SVE_SIG_{Z,P}REG_OFFSET, based off of
85      * the original struct pointer.
86      */
87 };
88 
89 #define TARGET_SVE_VQ_BYTES  16
90 
91 #define TARGET_SVE_SIG_ZREG_SIZE(VQ)  ((VQ) * TARGET_SVE_VQ_BYTES)
92 #define TARGET_SVE_SIG_PREG_SIZE(VQ)  ((VQ) * (TARGET_SVE_VQ_BYTES / 8))
93 
94 #define TARGET_SVE_SIG_REGS_OFFSET \
95     QEMU_ALIGN_UP(sizeof(struct target_sve_context), TARGET_SVE_VQ_BYTES)
96 #define TARGET_SVE_SIG_ZREG_OFFSET(VQ, N) \
97     (TARGET_SVE_SIG_REGS_OFFSET + TARGET_SVE_SIG_ZREG_SIZE(VQ) * (N))
98 #define TARGET_SVE_SIG_PREG_OFFSET(VQ, N) \
99     (TARGET_SVE_SIG_ZREG_OFFSET(VQ, 32) + TARGET_SVE_SIG_PREG_SIZE(VQ) * (N))
100 #define TARGET_SVE_SIG_FFR_OFFSET(VQ) \
101     (TARGET_SVE_SIG_PREG_OFFSET(VQ, 16))
102 #define TARGET_SVE_SIG_CONTEXT_SIZE(VQ) \
103     (TARGET_SVE_SIG_PREG_OFFSET(VQ, 17))
104 
105 #define TARGET_SVE_SIG_FLAG_SM  1
106 
107 #define TARGET_ZA_MAGIC        0x54366345
108 
109 struct target_za_context {
110     struct target_aarch64_ctx head;
111     uint16_t vl;
112     uint16_t reserved[3];
113     /* The actual ZA data immediately follows. */
114 };
115 
116 #define TARGET_ZA_SIG_REGS_OFFSET \
117     QEMU_ALIGN_UP(sizeof(struct target_za_context), TARGET_SVE_VQ_BYTES)
118 #define TARGET_ZA_SIG_ZAV_OFFSET(VQ, N) \
119     (TARGET_ZA_SIG_REGS_OFFSET + (VQ) * TARGET_SVE_VQ_BYTES * (N))
120 #define TARGET_ZA_SIG_CONTEXT_SIZE(VQ) \
121     TARGET_ZA_SIG_ZAV_OFFSET(VQ, VQ * TARGET_SVE_VQ_BYTES)
122 
123 struct target_rt_sigframe {
124     struct target_siginfo info;
125     struct target_ucontext uc;
126 };
127 
128 struct target_rt_frame_record {
129     uint64_t fp;
130     uint64_t lr;
131 };
132 
133 static void target_setup_general_frame(struct target_rt_sigframe *sf,
134                                        CPUARMState *env, target_sigset_t *set)
135 {
136     int i;
137 
138     __put_user(0, &sf->uc.tuc_flags);
139     __put_user(0, &sf->uc.tuc_link);
140 
141     target_save_altstack(&sf->uc.tuc_stack, env);
142 
143     for (i = 0; i < 31; i++) {
144         __put_user(env->xregs[i], &sf->uc.tuc_mcontext.regs[i]);
145     }
146     __put_user(env->xregs[31], &sf->uc.tuc_mcontext.sp);
147     __put_user(env->pc, &sf->uc.tuc_mcontext.pc);
148     __put_user(pstate_read(env), &sf->uc.tuc_mcontext.pstate);
149 
150     __put_user(env->exception.vaddress, &sf->uc.tuc_mcontext.fault_address);
151 
152     for (i = 0; i < TARGET_NSIG_WORDS; i++) {
153         __put_user(set->sig[i], &sf->uc.tuc_sigmask.sig[i]);
154     }
155 }
156 
157 static void target_setup_fpsimd_record(struct target_fpsimd_context *fpsimd,
158                                        CPUARMState *env)
159 {
160     int i;
161 
162     __put_user(TARGET_FPSIMD_MAGIC, &fpsimd->head.magic);
163     __put_user(sizeof(struct target_fpsimd_context), &fpsimd->head.size);
164     __put_user(vfp_get_fpsr(env), &fpsimd->fpsr);
165     __put_user(vfp_get_fpcr(env), &fpsimd->fpcr);
166 
167     for (i = 0; i < 32; i++) {
168         uint64_t *q = aa64_vfp_qreg(env, i);
169 #if TARGET_BIG_ENDIAN
170         __put_user(q[0], &fpsimd->vregs[i * 2 + 1]);
171         __put_user(q[1], &fpsimd->vregs[i * 2]);
172 #else
173         __put_user(q[0], &fpsimd->vregs[i * 2]);
174         __put_user(q[1], &fpsimd->vregs[i * 2 + 1]);
175 #endif
176     }
177 }
178 
179 static void target_setup_extra_record(struct target_extra_context *extra,
180                                       uint64_t datap, uint32_t extra_size)
181 {
182     __put_user(TARGET_EXTRA_MAGIC, &extra->head.magic);
183     __put_user(sizeof(struct target_extra_context), &extra->head.size);
184     __put_user(datap, &extra->datap);
185     __put_user(extra_size, &extra->size);
186 }
187 
188 static void target_setup_end_record(struct target_aarch64_ctx *end)
189 {
190     __put_user(0, &end->magic);
191     __put_user(0, &end->size);
192 }
193 
194 static void target_setup_sve_record(struct target_sve_context *sve,
195                                     CPUARMState *env, int size)
196 {
197     int i, j, vq = sve_vq(env);
198 
199     memset(sve, 0, sizeof(*sve));
200     __put_user(TARGET_SVE_MAGIC, &sve->head.magic);
201     __put_user(size, &sve->head.size);
202     __put_user(vq * TARGET_SVE_VQ_BYTES, &sve->vl);
203     if (FIELD_EX64(env->svcr, SVCR, SM)) {
204         __put_user(TARGET_SVE_SIG_FLAG_SM, &sve->flags);
205     }
206 
207     /* Note that SVE regs are stored as a byte stream, with each byte element
208      * at a subsequent address.  This corresponds to a little-endian store
209      * of our 64-bit hunks.
210      */
211     for (i = 0; i < 32; ++i) {
212         uint64_t *z = (void *)sve + TARGET_SVE_SIG_ZREG_OFFSET(vq, i);
213         for (j = 0; j < vq * 2; ++j) {
214             __put_user_e(env->vfp.zregs[i].d[j], z + j, le);
215         }
216     }
217     for (i = 0; i <= 16; ++i) {
218         uint16_t *p = (void *)sve + TARGET_SVE_SIG_PREG_OFFSET(vq, i);
219         for (j = 0; j < vq; ++j) {
220             uint64_t r = env->vfp.pregs[i].p[j >> 2];
221             __put_user_e(r >> ((j & 3) * 16), p + j, le);
222         }
223     }
224 }
225 
226 static void target_setup_za_record(struct target_za_context *za,
227                                    CPUARMState *env, int size)
228 {
229     int vq = sme_vq(env);
230     int vl = vq * TARGET_SVE_VQ_BYTES;
231     int i, j;
232 
233     memset(za, 0, sizeof(*za));
234     __put_user(TARGET_ZA_MAGIC, &za->head.magic);
235     __put_user(size, &za->head.size);
236     __put_user(vl, &za->vl);
237 
238     if (size == TARGET_ZA_SIG_CONTEXT_SIZE(0)) {
239         return;
240     }
241     assert(size == TARGET_ZA_SIG_CONTEXT_SIZE(vq));
242 
243     /*
244      * Note that ZA vectors are stored as a byte stream,
245      * with each byte element at a subsequent address.
246      */
247     for (i = 0; i < vl; ++i) {
248         uint64_t *z = (void *)za + TARGET_ZA_SIG_ZAV_OFFSET(vq, i);
249         for (j = 0; j < vq * 2; ++j) {
250             __put_user_e(env->zarray[i].d[j], z + j, le);
251         }
252     }
253 }
254 
255 static void target_restore_general_frame(CPUARMState *env,
256                                          struct target_rt_sigframe *sf)
257 {
258     sigset_t set;
259     uint64_t pstate;
260     int i;
261 
262     target_to_host_sigset(&set, &sf->uc.tuc_sigmask);
263     set_sigmask(&set);
264 
265     for (i = 0; i < 31; i++) {
266         __get_user(env->xregs[i], &sf->uc.tuc_mcontext.regs[i]);
267     }
268 
269     __get_user(env->xregs[31], &sf->uc.tuc_mcontext.sp);
270     __get_user(env->pc, &sf->uc.tuc_mcontext.pc);
271     __get_user(pstate, &sf->uc.tuc_mcontext.pstate);
272     pstate_write(env, pstate);
273 }
274 
275 static void target_restore_fpsimd_record(CPUARMState *env,
276                                          struct target_fpsimd_context *fpsimd)
277 {
278     uint32_t fpsr, fpcr;
279     int i;
280 
281     __get_user(fpsr, &fpsimd->fpsr);
282     vfp_set_fpsr(env, fpsr);
283     __get_user(fpcr, &fpsimd->fpcr);
284     vfp_set_fpcr(env, fpcr);
285 
286     for (i = 0; i < 32; i++) {
287         uint64_t *q = aa64_vfp_qreg(env, i);
288 #if TARGET_BIG_ENDIAN
289         __get_user(q[0], &fpsimd->vregs[i * 2 + 1]);
290         __get_user(q[1], &fpsimd->vregs[i * 2]);
291 #else
292         __get_user(q[0], &fpsimd->vregs[i * 2]);
293         __get_user(q[1], &fpsimd->vregs[i * 2 + 1]);
294 #endif
295     }
296 }
297 
298 static bool target_restore_sve_record(CPUARMState *env,
299                                       struct target_sve_context *sve,
300                                       int size, int *svcr)
301 {
302     int i, j, vl, vq, flags;
303     bool sm;
304 
305     __get_user(vl, &sve->vl);
306     __get_user(flags, &sve->flags);
307 
308     sm = flags & TARGET_SVE_SIG_FLAG_SM;
309 
310     /* The cpu must support Streaming or Non-streaming SVE. */
311     if (sm
312         ? !cpu_isar_feature(aa64_sme, env_archcpu(env))
313         : !cpu_isar_feature(aa64_sve, env_archcpu(env))) {
314         return false;
315     }
316 
317     /*
318      * Note that we cannot use sve_vq() because that depends on the
319      * current setting of PSTATE.SM, not the state to be restored.
320      */
321     vq = sve_vqm1_for_el_sm(env, 0, sm) + 1;
322 
323     /* Reject mismatched VL. */
324     if (vl != vq * TARGET_SVE_VQ_BYTES) {
325         return false;
326     }
327 
328     /* Accept empty record -- used to clear PSTATE.SM. */
329     if (size <= sizeof(*sve)) {
330         return true;
331     }
332 
333     /* Reject non-empty but incomplete record. */
334     if (size < TARGET_SVE_SIG_CONTEXT_SIZE(vq)) {
335         return false;
336     }
337 
338     *svcr = FIELD_DP64(*svcr, SVCR, SM, sm);
339 
340     /*
341      * Note that SVE regs are stored as a byte stream, with each byte element
342      * at a subsequent address.  This corresponds to a little-endian load
343      * of our 64-bit hunks.
344      */
345     for (i = 0; i < 32; ++i) {
346         uint64_t *z = (void *)sve + TARGET_SVE_SIG_ZREG_OFFSET(vq, i);
347         for (j = 0; j < vq * 2; ++j) {
348             __get_user_e(env->vfp.zregs[i].d[j], z + j, le);
349         }
350     }
351     for (i = 0; i <= 16; ++i) {
352         uint16_t *p = (void *)sve + TARGET_SVE_SIG_PREG_OFFSET(vq, i);
353         for (j = 0; j < vq; ++j) {
354             uint16_t r;
355             __get_user_e(r, p + j, le);
356             if (j & 3) {
357                 env->vfp.pregs[i].p[j >> 2] |= (uint64_t)r << ((j & 3) * 16);
358             } else {
359                 env->vfp.pregs[i].p[j >> 2] = r;
360             }
361         }
362     }
363     return true;
364 }
365 
366 static bool target_restore_za_record(CPUARMState *env,
367                                      struct target_za_context *za,
368                                      int size, int *svcr)
369 {
370     int i, j, vl, vq;
371 
372     if (!cpu_isar_feature(aa64_sme, env_archcpu(env))) {
373         return false;
374     }
375 
376     __get_user(vl, &za->vl);
377     vq = sme_vq(env);
378 
379     /* Reject mismatched VL. */
380     if (vl != vq * TARGET_SVE_VQ_BYTES) {
381         return false;
382     }
383 
384     /* Accept empty record -- used to clear PSTATE.ZA. */
385     if (size <= TARGET_ZA_SIG_CONTEXT_SIZE(0)) {
386         return true;
387     }
388 
389     /* Reject non-empty but incomplete record. */
390     if (size < TARGET_ZA_SIG_CONTEXT_SIZE(vq)) {
391         return false;
392     }
393 
394     *svcr = FIELD_DP64(*svcr, SVCR, ZA, 1);
395 
396     for (i = 0; i < vl; ++i) {
397         uint64_t *z = (void *)za + TARGET_ZA_SIG_ZAV_OFFSET(vq, i);
398         for (j = 0; j < vq * 2; ++j) {
399             __get_user_e(env->zarray[i].d[j], z + j, le);
400         }
401     }
402     return true;
403 }
404 
405 static int target_restore_sigframe(CPUARMState *env,
406                                    struct target_rt_sigframe *sf)
407 {
408     struct target_aarch64_ctx *ctx, *extra = NULL;
409     struct target_fpsimd_context *fpsimd = NULL;
410     struct target_sve_context *sve = NULL;
411     struct target_za_context *za = NULL;
412     uint64_t extra_datap = 0;
413     bool used_extra = false;
414     int sve_size = 0;
415     int za_size = 0;
416     int svcr = 0;
417 
418     target_restore_general_frame(env, sf);
419 
420     ctx = (struct target_aarch64_ctx *)sf->uc.tuc_mcontext.__reserved;
421     while (ctx) {
422         uint32_t magic, size, extra_size;
423 
424         __get_user(magic, &ctx->magic);
425         __get_user(size, &ctx->size);
426         switch (magic) {
427         case 0:
428             if (size != 0) {
429                 goto err;
430             }
431             if (used_extra) {
432                 ctx = NULL;
433             } else {
434                 ctx = extra;
435                 used_extra = true;
436             }
437             continue;
438 
439         case TARGET_FPSIMD_MAGIC:
440             if (fpsimd || size != sizeof(struct target_fpsimd_context)) {
441                 goto err;
442             }
443             fpsimd = (struct target_fpsimd_context *)ctx;
444             break;
445 
446         case TARGET_SVE_MAGIC:
447             if (sve || size < sizeof(struct target_sve_context)) {
448                 goto err;
449             }
450             sve = (struct target_sve_context *)ctx;
451             sve_size = size;
452             break;
453 
454         case TARGET_ZA_MAGIC:
455             if (za || size < sizeof(struct target_za_context)) {
456                 goto err;
457             }
458             za = (struct target_za_context *)ctx;
459             za_size = size;
460             break;
461 
462         case TARGET_EXTRA_MAGIC:
463             if (extra || size != sizeof(struct target_extra_context)) {
464                 goto err;
465             }
466             __get_user(extra_datap,
467                        &((struct target_extra_context *)ctx)->datap);
468             __get_user(extra_size,
469                        &((struct target_extra_context *)ctx)->size);
470             extra = lock_user(VERIFY_READ, extra_datap, extra_size, 0);
471             if (!extra) {
472                 return 1;
473             }
474             break;
475 
476         default:
477             /* Unknown record -- we certainly didn't generate it.
478              * Did we in fact get out of sync?
479              */
480             goto err;
481         }
482         ctx = (void *)ctx + size;
483     }
484 
485     /* Require FPSIMD always.  */
486     if (fpsimd) {
487         target_restore_fpsimd_record(env, fpsimd);
488     } else {
489         goto err;
490     }
491 
492     /* SVE data, if present, overwrites FPSIMD data.  */
493     if (sve && !target_restore_sve_record(env, sve, sve_size, &svcr)) {
494         goto err;
495     }
496     if (za && !target_restore_za_record(env, za, za_size, &svcr)) {
497         goto err;
498     }
499     if (env->svcr != svcr) {
500         env->svcr = svcr;
501         arm_rebuild_hflags(env);
502     }
503     unlock_user(extra, extra_datap, 0);
504     return 0;
505 
506  err:
507     unlock_user(extra, extra_datap, 0);
508     return 1;
509 }
510 
511 static abi_ulong get_sigframe(struct target_sigaction *ka,
512                               CPUARMState *env, int size)
513 {
514     abi_ulong sp;
515 
516     sp = target_sigsp(get_sp_from_cpustate(env), ka);
517 
518     sp = (sp - size) & ~15;
519 
520     return sp;
521 }
522 
523 typedef struct {
524     int total_size;
525     int extra_base;
526     int extra_size;
527     int std_end_ofs;
528     int extra_ofs;
529     int extra_end_ofs;
530 } target_sigframe_layout;
531 
532 static int alloc_sigframe_space(int this_size, target_sigframe_layout *l)
533 {
534     /* Make sure there will always be space for the end marker.  */
535     const int std_size = sizeof(struct target_rt_sigframe)
536                          - sizeof(struct target_aarch64_ctx);
537     int this_loc = l->total_size;
538 
539     if (l->extra_base) {
540         /* Once we have begun an extra space, all allocations go there.  */
541         l->extra_size += this_size;
542     } else if (this_size + this_loc > std_size) {
543         /* This allocation does not fit in the standard space.  */
544         /* Allocate the extra record.  */
545         l->extra_ofs = this_loc;
546         l->total_size += sizeof(struct target_extra_context);
547 
548         /* Allocate the standard end record.  */
549         l->std_end_ofs = l->total_size;
550         l->total_size += sizeof(struct target_aarch64_ctx);
551 
552         /* Allocate the requested record.  */
553         l->extra_base = this_loc = l->total_size;
554         l->extra_size = this_size;
555     }
556     l->total_size += this_size;
557 
558     return this_loc;
559 }
560 
561 static void target_setup_frame(int usig, struct target_sigaction *ka,
562                                target_siginfo_t *info, target_sigset_t *set,
563                                CPUARMState *env)
564 {
565     target_sigframe_layout layout = {
566         /* Begin with the size pointing to the reserved space.  */
567         .total_size = offsetof(struct target_rt_sigframe,
568                                uc.tuc_mcontext.__reserved),
569     };
570     int fpsimd_ofs, fr_ofs, sve_ofs = 0, za_ofs = 0;
571     int sve_size = 0, za_size = 0;
572     struct target_rt_sigframe *frame;
573     struct target_rt_frame_record *fr;
574     abi_ulong frame_addr, return_addr;
575 
576     /* FPSIMD record is always in the standard space.  */
577     fpsimd_ofs = alloc_sigframe_space(sizeof(struct target_fpsimd_context),
578                                       &layout);
579 
580     /* SVE state needs saving only if it exists.  */
581     if (cpu_isar_feature(aa64_sve, env_archcpu(env)) ||
582         cpu_isar_feature(aa64_sme, env_archcpu(env))) {
583         sve_size = QEMU_ALIGN_UP(TARGET_SVE_SIG_CONTEXT_SIZE(sve_vq(env)), 16);
584         sve_ofs = alloc_sigframe_space(sve_size, &layout);
585     }
586     if (cpu_isar_feature(aa64_sme, env_archcpu(env))) {
587         /* ZA state needs saving only if it is enabled.  */
588         if (FIELD_EX64(env->svcr, SVCR, ZA)) {
589             za_size = TARGET_ZA_SIG_CONTEXT_SIZE(sme_vq(env));
590         } else {
591             za_size = TARGET_ZA_SIG_CONTEXT_SIZE(0);
592         }
593         za_ofs = alloc_sigframe_space(za_size, &layout);
594     }
595 
596     if (layout.extra_ofs) {
597         /* Reserve space for the extra end marker.  The standard end marker
598          * will have been allocated when we allocated the extra record.
599          */
600         layout.extra_end_ofs
601             = alloc_sigframe_space(sizeof(struct target_aarch64_ctx), &layout);
602     } else {
603         /* Reserve space for the standard end marker.
604          * Do not use alloc_sigframe_space because we cheat
605          * std_size therein to reserve space for this.
606          */
607         layout.std_end_ofs = layout.total_size;
608         layout.total_size += sizeof(struct target_aarch64_ctx);
609     }
610 
611     /* We must always provide at least the standard 4K reserved space,
612      * even if we don't use all of it (this is part of the ABI)
613      */
614     layout.total_size = MAX(layout.total_size,
615                             sizeof(struct target_rt_sigframe));
616 
617     /*
618      * Reserve space for the standard frame unwind pair: fp, lr.
619      * Despite the name this is not a "real" record within the frame.
620      */
621     fr_ofs = layout.total_size;
622     layout.total_size += sizeof(struct target_rt_frame_record);
623 
624     frame_addr = get_sigframe(ka, env, layout.total_size);
625     trace_user_setup_frame(env, frame_addr);
626     frame = lock_user(VERIFY_WRITE, frame_addr, layout.total_size, 0);
627     if (!frame) {
628         goto give_sigsegv;
629     }
630 
631     target_setup_general_frame(frame, env, set);
632     target_setup_fpsimd_record((void *)frame + fpsimd_ofs, env);
633     target_setup_end_record((void *)frame + layout.std_end_ofs);
634     if (layout.extra_ofs) {
635         target_setup_extra_record((void *)frame + layout.extra_ofs,
636                                   frame_addr + layout.extra_base,
637                                   layout.extra_size);
638         target_setup_end_record((void *)frame + layout.extra_end_ofs);
639     }
640     if (sve_ofs) {
641         target_setup_sve_record((void *)frame + sve_ofs, env, sve_size);
642     }
643     if (za_ofs) {
644         target_setup_za_record((void *)frame + za_ofs, env, za_size);
645     }
646 
647     /* Set up the stack frame for unwinding.  */
648     fr = (void *)frame + fr_ofs;
649     __put_user(env->xregs[29], &fr->fp);
650     __put_user(env->xregs[30], &fr->lr);
651 
652     if (ka->sa_flags & TARGET_SA_RESTORER) {
653         return_addr = ka->sa_restorer;
654     } else {
655         return_addr = default_rt_sigreturn;
656     }
657     env->xregs[0] = usig;
658     env->xregs[29] = frame_addr + fr_ofs;
659     env->xregs[30] = return_addr;
660     env->xregs[31] = frame_addr;
661     env->pc = ka->_sa_handler;
662 
663     /* Invoke the signal handler as if by indirect call.  */
664     if (cpu_isar_feature(aa64_bti, env_archcpu(env))) {
665         env->btype = 2;
666     }
667 
668     /*
669      * Invoke the signal handler with both SM and ZA disabled.
670      * When clearing SM, ResetSVEState, per SMSTOP.
671      */
672     if (FIELD_EX64(env->svcr, SVCR, SM)) {
673         arm_reset_sve_state(env);
674     }
675     if (env->svcr) {
676         env->svcr = 0;
677         arm_rebuild_hflags(env);
678     }
679 
680     if (info) {
681         tswap_siginfo(&frame->info, info);
682         env->xregs[1] = frame_addr + offsetof(struct target_rt_sigframe, info);
683         env->xregs[2] = frame_addr + offsetof(struct target_rt_sigframe, uc);
684     }
685 
686     unlock_user(frame, frame_addr, layout.total_size);
687     return;
688 
689  give_sigsegv:
690     unlock_user(frame, frame_addr, layout.total_size);
691     force_sigsegv(usig);
692 }
693 
694 void setup_rt_frame(int sig, struct target_sigaction *ka,
695                     target_siginfo_t *info, target_sigset_t *set,
696                     CPUARMState *env)
697 {
698     target_setup_frame(sig, ka, info, set, env);
699 }
700 
701 void setup_frame(int sig, struct target_sigaction *ka,
702                  target_sigset_t *set, CPUARMState *env)
703 {
704     target_setup_frame(sig, ka, 0, set, env);
705 }
706 
707 long do_rt_sigreturn(CPUARMState *env)
708 {
709     struct target_rt_sigframe *frame = NULL;
710     abi_ulong frame_addr = env->xregs[31];
711 
712     trace_user_do_rt_sigreturn(env, frame_addr);
713     if (frame_addr & 15) {
714         goto badframe;
715     }
716 
717     if  (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1)) {
718         goto badframe;
719     }
720 
721     if (target_restore_sigframe(env, frame)) {
722         goto badframe;
723     }
724 
725     target_restore_altstack(&frame->uc.tuc_stack, env);
726 
727     unlock_user_struct(frame, frame_addr, 0);
728     return -QEMU_ESIGRETURN;
729 
730  badframe:
731     unlock_user_struct(frame, frame_addr, 0);
732     force_sig(TARGET_SIGSEGV);
733     return -QEMU_ESIGRETURN;
734 }
735 
736 long do_sigreturn(CPUARMState *env)
737 {
738     return do_rt_sigreturn(env);
739 }
740 
741 void setup_sigtramp(abi_ulong sigtramp_page)
742 {
743     uint32_t *tramp = lock_user(VERIFY_WRITE, sigtramp_page, 8, 0);
744     assert(tramp != NULL);
745 
746     /*
747      * mov x8,#__NR_rt_sigreturn; svc #0
748      * Since these are instructions they need to be put as little-endian
749      * regardless of target default or current CPU endianness.
750      */
751     __put_user_e(0xd2801168, &tramp[0], le);
752     __put_user_e(0xd4000001, &tramp[1], le);
753 
754     default_rt_sigreturn = sigtramp_page;
755     unlock_user(tramp, sigtramp_page, 8);
756 }
757