xref: /openbmc/qemu/linux-user/sparc/signal.c (revision 7200fb21)
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 /* A Sparc register window */
26 struct target_reg_window {
27     abi_ulong locals[8];
28     abi_ulong ins[8];
29 };
30 
31 /* A Sparc stack frame. */
32 struct target_stackf {
33     /*
34      * Since qemu does not reference fp or callers_pc directly,
35      * it's simpler to treat fp and callers_pc as elements of ins[],
36      * and then bundle locals[] and ins[] into reg_window.
37      */
38     struct target_reg_window win;
39     /*
40      * Similarly, bundle structptr and xxargs into xargs[].
41      * This portion of the struct is part of the function call abi,
42      * and belongs to the callee for spilling argument registers.
43      */
44     abi_ulong xargs[8];
45 };
46 
47 struct target_siginfo_fpu {
48 #ifdef TARGET_SPARC64
49     uint64_t si_double_regs[32];
50     uint64_t si_fsr;
51     uint64_t si_gsr;
52     uint64_t si_fprs;
53 #else
54     /* It is more convenient for qemu to move doubles, not singles. */
55     uint64_t si_double_regs[16];
56     uint32_t si_fsr;
57     uint32_t si_fpqdepth;
58     struct {
59         uint32_t insn_addr;
60         uint32_t insn;
61     } si_fpqueue [16];
62 #endif
63 };
64 
65 #ifdef TARGET_ARCH_HAS_SETUP_FRAME
66 struct target_signal_frame {
67     struct target_stackf ss;
68     struct target_pt_regs regs;
69     uint32_t si_mask;
70     abi_ulong fpu_save;
71     uint32_t insns[2] QEMU_ALIGNED(8);
72     abi_ulong extramask[TARGET_NSIG_WORDS - 1];
73     abi_ulong extra_size; /* Should be 0 */
74     abi_ulong rwin_save;
75 };
76 #endif
77 
78 struct target_rt_signal_frame {
79     struct target_stackf ss;
80     target_siginfo_t info;
81     struct target_pt_regs regs;
82 #if defined(TARGET_SPARC64) && !defined(TARGET_ABI32)
83     abi_ulong fpu_save;
84     target_stack_t stack;
85     target_sigset_t mask;
86 #else
87     target_sigset_t mask;
88     abi_ulong fpu_save;
89     uint32_t insns[2];
90     target_stack_t stack;
91     abi_ulong extra_size; /* Should be 0 */
92 #endif
93     abi_ulong rwin_save;
94 };
95 
96 static abi_ulong get_sigframe(struct target_sigaction *sa,
97                               CPUSPARCState *env,
98                               size_t framesize)
99 {
100     abi_ulong sp = get_sp_from_cpustate(env);
101 
102     /*
103      * If we are on the alternate signal stack and would overflow it, don't.
104      * Return an always-bogus address instead so we will die with SIGSEGV.
105      */
106     if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize))) {
107         return -1;
108     }
109 
110     /* This is the X/Open sanctioned signal stack switching.  */
111     sp = target_sigsp(sp, sa) - framesize;
112 
113     /*
114      * Always align the stack frame.  This handles two cases.  First,
115      * sigaltstack need not be mindful of platform specific stack
116      * alignment.  Second, if we took this signal because the stack
117      * is not aligned properly, we'd like to take the signal cleanly
118      * and report that.
119      */
120     sp &= ~15UL;
121 
122     return sp;
123 }
124 
125 static void save_pt_regs(struct target_pt_regs *regs, CPUSPARCState *env)
126 {
127     int i;
128 
129 #if defined(TARGET_SPARC64) && !defined(TARGET_ABI32)
130     __put_user(sparc64_tstate(env), &regs->tstate);
131     /* TODO: magic should contain PT_REG_MAGIC + %tt. */
132     __put_user(0, &regs->magic);
133 #else
134     __put_user(cpu_get_psr(env), &regs->psr);
135 #endif
136 
137     __put_user(env->pc, &regs->pc);
138     __put_user(env->npc, &regs->npc);
139     __put_user(env->y, &regs->y);
140 
141     for (i = 0; i < 8; i++) {
142         __put_user(env->gregs[i], &regs->u_regs[i]);
143     }
144     for (i = 0; i < 8; i++) {
145         __put_user(env->regwptr[WREG_O0 + i], &regs->u_regs[i + 8]);
146     }
147 }
148 
149 static void restore_pt_regs(struct target_pt_regs *regs, CPUSPARCState *env)
150 {
151     int i;
152 
153 #if defined(TARGET_SPARC64) && !defined(TARGET_ABI32)
154     /* User can only change condition codes and %asi in %tstate. */
155     uint64_t tstate;
156     __get_user(tstate, &regs->tstate);
157     cpu_put_ccr(env, tstate >> 32);
158     env->asi = extract64(tstate, 24, 8);
159 #else
160     /*
161      * User can only change condition codes and FPU enabling in %psr.
162      * But don't bother with FPU enabling, since a real kernel would
163      * just re-enable the FPU upon the next fpu trap.
164      */
165     uint32_t psr;
166     __get_user(psr, &regs->psr);
167     cpu_put_psr_icc(env, psr);
168 #endif
169 
170     /* Note that pc and npc are handled in the caller. */
171 
172     __get_user(env->y, &regs->y);
173 
174     for (i = 0; i < 8; i++) {
175         __get_user(env->gregs[i], &regs->u_regs[i]);
176     }
177     for (i = 0; i < 8; i++) {
178         __get_user(env->regwptr[WREG_O0 + i], &regs->u_regs[i + 8]);
179     }
180 }
181 
182 static void save_reg_win(struct target_reg_window *win, CPUSPARCState *env)
183 {
184     int i;
185 
186     for (i = 0; i < 8; i++) {
187         __put_user(env->regwptr[i + WREG_L0], &win->locals[i]);
188     }
189     for (i = 0; i < 8; i++) {
190         __put_user(env->regwptr[i + WREG_I0], &win->ins[i]);
191     }
192 }
193 
194 static void save_fpu(struct target_siginfo_fpu *fpu, CPUSPARCState *env)
195 {
196     int i;
197 
198 #ifdef TARGET_SPARC64
199     for (i = 0; i < 32; ++i) {
200         __put_user(env->fpr[i].ll, &fpu->si_double_regs[i]);
201     }
202     __put_user(env->fsr, &fpu->si_fsr);
203     __put_user(env->gsr, &fpu->si_gsr);
204     __put_user(env->fprs, &fpu->si_fprs);
205 #else
206     for (i = 0; i < 16; ++i) {
207         __put_user(env->fpr[i].ll, &fpu->si_double_regs[i]);
208     }
209     __put_user(env->fsr, &fpu->si_fsr);
210     __put_user(0, &fpu->si_fpqdepth);
211 #endif
212 }
213 
214 static void restore_fpu(struct target_siginfo_fpu *fpu, CPUSPARCState *env)
215 {
216     int i;
217 
218 #ifdef TARGET_SPARC64
219     uint64_t fprs;
220     __get_user(fprs, &fpu->si_fprs);
221 
222     /* In case the user mucks about with FPRS, restore as directed. */
223     if (fprs & FPRS_DL) {
224         for (i = 0; i < 16; ++i) {
225             __get_user(env->fpr[i].ll, &fpu->si_double_regs[i]);
226         }
227     }
228     if (fprs & FPRS_DU) {
229         for (i = 16; i < 32; ++i) {
230             __get_user(env->fpr[i].ll, &fpu->si_double_regs[i]);
231         }
232     }
233     __get_user(env->fsr, &fpu->si_fsr);
234     __get_user(env->gsr, &fpu->si_gsr);
235     env->fprs |= fprs;
236 #else
237     for (i = 0; i < 16; ++i) {
238         __get_user(env->fpr[i].ll, &fpu->si_double_regs[i]);
239     }
240     __get_user(env->fsr, &fpu->si_fsr);
241 #endif
242 }
243 
244 #ifdef TARGET_ARCH_HAS_SETUP_FRAME
245 static void install_sigtramp(uint32_t *tramp, int syscall)
246 {
247     __put_user(0x82102000u + syscall, &tramp[0]); /* mov syscall, %g1 */
248     __put_user(0x91d02010u, &tramp[1]);           /* t 0x10 */
249 }
250 
251 void setup_frame(int sig, struct target_sigaction *ka,
252                  target_sigset_t *set, CPUSPARCState *env)
253 {
254     abi_ulong sf_addr;
255     struct target_signal_frame *sf;
256     size_t sf_size = sizeof(*sf) + sizeof(struct target_siginfo_fpu);
257     int i;
258 
259     sf_addr = get_sigframe(ka, env, sf_size);
260     trace_user_setup_frame(env, sf_addr);
261 
262     sf = lock_user(VERIFY_WRITE, sf_addr, sf_size, 0);
263     if (!sf) {
264         force_sigsegv(sig);
265         return;
266     }
267 
268     /* 2. Save the current process state */
269     save_pt_regs(&sf->regs, env);
270     __put_user(0, &sf->extra_size);
271 
272     save_fpu((struct target_siginfo_fpu *)(sf + 1), env);
273     __put_user(sf_addr + sizeof(*sf), &sf->fpu_save);
274 
275     __put_user(0, &sf->rwin_save);  /* TODO: save_rwin_state */
276 
277     __put_user(set->sig[0], &sf->si_mask);
278     for (i = 0; i < TARGET_NSIG_WORDS - 1; i++) {
279         __put_user(set->sig[i + 1], &sf->extramask[i]);
280     }
281 
282     save_reg_win(&sf->ss.win, env);
283 
284     /* 3. signal handler back-trampoline and parameters */
285     env->regwptr[WREG_SP] = sf_addr;
286     env->regwptr[WREG_O0] = sig;
287     env->regwptr[WREG_O1] = sf_addr +
288             offsetof(struct target_signal_frame, regs);
289     env->regwptr[WREG_O2] = sf_addr +
290             offsetof(struct target_signal_frame, regs);
291 
292     /* 4. signal handler */
293     env->pc = ka->_sa_handler;
294     env->npc = env->pc + 4;
295 
296     /* 5. return to kernel instructions */
297     if (ka->ka_restorer) {
298         env->regwptr[WREG_O7] = ka->ka_restorer;
299     } else {
300         /* Not used, but retain for ABI compatibility. */
301         install_sigtramp(sf->insns, TARGET_NR_sigreturn);
302         env->regwptr[WREG_O7] = default_sigreturn;
303     }
304     unlock_user(sf, sf_addr, sf_size);
305 }
306 #endif /* TARGET_ARCH_HAS_SETUP_FRAME */
307 
308 void setup_rt_frame(int sig, struct target_sigaction *ka,
309                     target_siginfo_t *info,
310                     target_sigset_t *set, CPUSPARCState *env)
311 {
312     abi_ulong sf_addr;
313     struct target_rt_signal_frame *sf;
314     size_t sf_size = sizeof(*sf) + sizeof(struct target_siginfo_fpu);
315 
316     sf_addr = get_sigframe(ka, env, sf_size);
317     trace_user_setup_rt_frame(env, sf_addr);
318 
319     sf = lock_user(VERIFY_WRITE, sf_addr, sf_size, 0);
320     if (!sf) {
321         force_sigsegv(sig);
322         return;
323     }
324 
325     /* 2. Save the current process state */
326     save_reg_win(&sf->ss.win, env);
327     save_pt_regs(&sf->regs, env);
328 
329     save_fpu((struct target_siginfo_fpu *)(sf + 1), env);
330     __put_user(sf_addr + sizeof(*sf), &sf->fpu_save);
331 
332     __put_user(0, &sf->rwin_save);  /* TODO: save_rwin_state */
333 
334     tswap_siginfo(&sf->info, info);
335     tswap_sigset(&sf->mask, set);
336     target_save_altstack(&sf->stack, env);
337 
338 #ifdef TARGET_ABI32
339     __put_user(0, &sf->extra_size);
340 #endif
341 
342     /* 3. signal handler back-trampoline and parameters */
343     env->regwptr[WREG_SP] = sf_addr - TARGET_STACK_BIAS;
344     env->regwptr[WREG_O0] = sig;
345     env->regwptr[WREG_O1] =
346         sf_addr + offsetof(struct target_rt_signal_frame, info);
347 #ifdef TARGET_ABI32
348     env->regwptr[WREG_O2] =
349         sf_addr + offsetof(struct target_rt_signal_frame, regs);
350 #else
351     env->regwptr[WREG_O2] = env->regwptr[WREG_O1];
352 #endif
353 
354     /* 4. signal handler */
355     env->pc = ka->_sa_handler;
356     env->npc = env->pc + 4;
357 
358     /* 5. return to kernel instructions */
359 #ifdef TARGET_ABI32
360     if (ka->ka_restorer) {
361         env->regwptr[WREG_O7] = ka->ka_restorer;
362     } else {
363         /* Not used, but retain for ABI compatibility. */
364         install_sigtramp(sf->insns, TARGET_NR_rt_sigreturn);
365         env->regwptr[WREG_O7] = default_rt_sigreturn;
366     }
367 #else
368     env->regwptr[WREG_O7] = ka->ka_restorer;
369 #endif
370 
371     unlock_user(sf, sf_addr, sf_size);
372 }
373 
374 long do_sigreturn(CPUSPARCState *env)
375 {
376 #ifdef TARGET_ARCH_HAS_SETUP_FRAME
377     abi_ulong sf_addr;
378     struct target_signal_frame *sf = NULL;
379     abi_ulong pc, npc, ptr;
380     target_sigset_t set;
381     sigset_t host_set;
382     int i;
383 
384     sf_addr = env->regwptr[WREG_SP];
385     trace_user_do_sigreturn(env, sf_addr);
386 
387     /* 1. Make sure we are not getting garbage from the user */
388     if ((sf_addr & 15) || !lock_user_struct(VERIFY_READ, sf, sf_addr, 1)) {
389         goto segv_and_exit;
390     }
391 
392     /* Make sure stack pointer is aligned.  */
393     __get_user(ptr, &sf->regs.u_regs[14]);
394     if (ptr & 7) {
395         goto segv_and_exit;
396     }
397 
398     /* Make sure instruction pointers are aligned.  */
399     __get_user(pc, &sf->regs.pc);
400     __get_user(npc, &sf->regs.npc);
401     if ((pc | npc) & 3) {
402         goto segv_and_exit;
403     }
404 
405     /* 2. Restore the state */
406     restore_pt_regs(&sf->regs, env);
407     env->pc = pc;
408     env->npc = npc;
409 
410     __get_user(ptr, &sf->fpu_save);
411     if (ptr) {
412         struct target_siginfo_fpu *fpu;
413         if ((ptr & 3) || !lock_user_struct(VERIFY_READ, fpu, ptr, 1)) {
414             goto segv_and_exit;
415         }
416         restore_fpu(fpu, env);
417         unlock_user_struct(fpu, ptr, 0);
418     }
419 
420     __get_user(ptr, &sf->rwin_save);
421     if (ptr) {
422         goto segv_and_exit;  /* TODO: restore_rwin */
423     }
424 
425     __get_user(set.sig[0], &sf->si_mask);
426     for (i = 1; i < TARGET_NSIG_WORDS; i++) {
427         __get_user(set.sig[i], &sf->extramask[i - 1]);
428     }
429 
430     target_to_host_sigset_internal(&host_set, &set);
431     set_sigmask(&host_set);
432 
433     unlock_user_struct(sf, sf_addr, 0);
434     return -QEMU_ESIGRETURN;
435 
436  segv_and_exit:
437     unlock_user_struct(sf, sf_addr, 0);
438     force_sig(TARGET_SIGSEGV);
439     return -QEMU_ESIGRETURN;
440 #else
441     return -TARGET_ENOSYS;
442 #endif
443 }
444 
445 long do_rt_sigreturn(CPUSPARCState *env)
446 {
447     abi_ulong sf_addr, tpc, tnpc, ptr;
448     struct target_rt_signal_frame *sf = NULL;
449     sigset_t set;
450 
451     sf_addr = get_sp_from_cpustate(env);
452     trace_user_do_rt_sigreturn(env, sf_addr);
453 
454     /* 1. Make sure we are not getting garbage from the user */
455     if ((sf_addr & 15) || !lock_user_struct(VERIFY_READ, sf, sf_addr, 1)) {
456         goto segv_and_exit;
457     }
458 
459     /* Validate SP alignment.  */
460     __get_user(ptr, &sf->regs.u_regs[8 + WREG_SP]);
461     if ((ptr + TARGET_STACK_BIAS) & 7) {
462         goto segv_and_exit;
463     }
464 
465     /* Validate PC and NPC alignment.  */
466     __get_user(tpc, &sf->regs.pc);
467     __get_user(tnpc, &sf->regs.npc);
468     if ((tpc | tnpc) & 3) {
469         goto segv_and_exit;
470     }
471 
472     /* 2. Restore the state */
473     restore_pt_regs(&sf->regs, env);
474 
475     __get_user(ptr, &sf->fpu_save);
476     if (ptr) {
477         struct target_siginfo_fpu *fpu;
478         if ((ptr & 7) || !lock_user_struct(VERIFY_READ, fpu, ptr, 1)) {
479             goto segv_and_exit;
480         }
481         restore_fpu(fpu, env);
482         unlock_user_struct(fpu, ptr, 0);
483     }
484 
485     __get_user(ptr, &sf->rwin_save);
486     if (ptr) {
487         goto segv_and_exit;  /* TODO: restore_rwin_state */
488     }
489 
490     target_restore_altstack(&sf->stack, env);
491     target_to_host_sigset(&set, &sf->mask);
492     set_sigmask(&set);
493 
494     env->pc = tpc;
495     env->npc = tnpc;
496 
497     unlock_user_struct(sf, sf_addr, 0);
498     return -QEMU_ESIGRETURN;
499 
500  segv_and_exit:
501     unlock_user_struct(sf, sf_addr, 0);
502     force_sig(TARGET_SIGSEGV);
503     return -QEMU_ESIGRETURN;
504 }
505 
506 #ifdef TARGET_ABI32
507 void setup_sigtramp(abi_ulong sigtramp_page)
508 {
509     uint32_t *tramp = lock_user(VERIFY_WRITE, sigtramp_page, 2 * 8, 0);
510     assert(tramp != NULL);
511 
512     default_sigreturn = sigtramp_page;
513     install_sigtramp(tramp, TARGET_NR_sigreturn);
514 
515     default_rt_sigreturn = sigtramp_page + 8;
516     install_sigtramp(tramp + 2, TARGET_NR_rt_sigreturn);
517 
518     unlock_user(tramp, sigtramp_page, 2 * 8);
519 }
520 #endif
521 
522 #ifdef TARGET_SPARC64
523 #define SPARC_MC_TSTATE 0
524 #define SPARC_MC_PC 1
525 #define SPARC_MC_NPC 2
526 #define SPARC_MC_Y 3
527 #define SPARC_MC_G1 4
528 #define SPARC_MC_G2 5
529 #define SPARC_MC_G3 6
530 #define SPARC_MC_G4 7
531 #define SPARC_MC_G5 8
532 #define SPARC_MC_G6 9
533 #define SPARC_MC_G7 10
534 #define SPARC_MC_O0 11
535 #define SPARC_MC_O1 12
536 #define SPARC_MC_O2 13
537 #define SPARC_MC_O3 14
538 #define SPARC_MC_O4 15
539 #define SPARC_MC_O5 16
540 #define SPARC_MC_O6 17
541 #define SPARC_MC_O7 18
542 #define SPARC_MC_NGREG 19
543 
544 typedef abi_ulong target_mc_greg_t;
545 typedef target_mc_greg_t target_mc_gregset_t[SPARC_MC_NGREG];
546 
547 struct target_mc_fq {
548     abi_ulong mcfq_addr;
549     uint32_t mcfq_insn;
550 };
551 
552 /*
553  * Note the manual 16-alignment; the kernel gets this because it
554  * includes a "long double qregs[16]" in the mcpu_fregs union,
555  * which we can't do.
556  */
557 struct target_mc_fpu {
558     union {
559         uint32_t sregs[32];
560         uint64_t dregs[32];
561         //uint128_t qregs[16];
562     } mcfpu_fregs;
563     abi_ulong mcfpu_fsr;
564     abi_ulong mcfpu_fprs;
565     abi_ulong mcfpu_gsr;
566     abi_ulong mcfpu_fq;
567     unsigned char mcfpu_qcnt;
568     unsigned char mcfpu_qentsz;
569     unsigned char mcfpu_enab;
570 } __attribute__((aligned(16)));
571 typedef struct target_mc_fpu target_mc_fpu_t;
572 
573 typedef struct {
574     target_mc_gregset_t mc_gregs;
575     target_mc_greg_t mc_fp;
576     target_mc_greg_t mc_i7;
577     target_mc_fpu_t mc_fpregs;
578 } target_mcontext_t;
579 
580 struct target_ucontext {
581     abi_ulong tuc_link;
582     abi_ulong tuc_flags;
583     target_sigset_t tuc_sigmask;
584     target_mcontext_t tuc_mcontext;
585 };
586 
587 /* {set, get}context() needed for 64-bit SparcLinux userland. */
588 void sparc64_set_context(CPUSPARCState *env)
589 {
590     abi_ulong ucp_addr;
591     struct target_ucontext *ucp;
592     target_mc_gregset_t *grp;
593     target_mc_fpu_t *fpup;
594     target_ulong pc, npc, tstate;
595     unsigned int i;
596     unsigned char fenab;
597 
598     ucp_addr = env->regwptr[WREG_O0];
599     if (!lock_user_struct(VERIFY_READ, ucp, ucp_addr, 1)) {
600         goto do_sigsegv;
601     }
602     grp  = &ucp->tuc_mcontext.mc_gregs;
603     __get_user(pc, &((*grp)[SPARC_MC_PC]));
604     __get_user(npc, &((*grp)[SPARC_MC_NPC]));
605     if ((pc | npc) & 3) {
606         goto do_sigsegv;
607     }
608     if (env->regwptr[WREG_O1]) {
609         target_sigset_t target_set;
610         sigset_t set;
611 
612         if (TARGET_NSIG_WORDS == 1) {
613             __get_user(target_set.sig[0], &ucp->tuc_sigmask.sig[0]);
614         } else {
615             abi_ulong *src, *dst;
616             src = ucp->tuc_sigmask.sig;
617             dst = target_set.sig;
618             for (i = 0; i < TARGET_NSIG_WORDS; i++, dst++, src++) {
619                 __get_user(*dst, src);
620             }
621         }
622         target_to_host_sigset_internal(&set, &target_set);
623         set_sigmask(&set);
624     }
625     env->pc = pc;
626     env->npc = npc;
627     __get_user(env->y, &((*grp)[SPARC_MC_Y]));
628     __get_user(tstate, &((*grp)[SPARC_MC_TSTATE]));
629     /* Honour TSTATE_ASI, TSTATE_ICC and TSTATE_XCC only */
630     env->asi = (tstate >> 24) & 0xff;
631     cpu_put_ccr(env, (tstate >> 32) & 0xff);
632     __get_user(env->gregs[1], (&(*grp)[SPARC_MC_G1]));
633     __get_user(env->gregs[2], (&(*grp)[SPARC_MC_G2]));
634     __get_user(env->gregs[3], (&(*grp)[SPARC_MC_G3]));
635     __get_user(env->gregs[4], (&(*grp)[SPARC_MC_G4]));
636     __get_user(env->gregs[5], (&(*grp)[SPARC_MC_G5]));
637     __get_user(env->gregs[6], (&(*grp)[SPARC_MC_G6]));
638     /* Skip g7 as that's the thread register in userspace */
639 
640     /*
641      * Note that unlike the kernel, we didn't need to mess with the
642      * guest register window state to save it into a pt_regs to run
643      * the kernel. So for us the guest's O regs are still in WREG_O*
644      * (unlike the kernel which has put them in UREG_I* in a pt_regs)
645      * and the fp and i7 are still in WREG_I6 and WREG_I7 and don't
646      * need to be written back to userspace memory.
647      */
648     __get_user(env->regwptr[WREG_O0], (&(*grp)[SPARC_MC_O0]));
649     __get_user(env->regwptr[WREG_O1], (&(*grp)[SPARC_MC_O1]));
650     __get_user(env->regwptr[WREG_O2], (&(*grp)[SPARC_MC_O2]));
651     __get_user(env->regwptr[WREG_O3], (&(*grp)[SPARC_MC_O3]));
652     __get_user(env->regwptr[WREG_O4], (&(*grp)[SPARC_MC_O4]));
653     __get_user(env->regwptr[WREG_O5], (&(*grp)[SPARC_MC_O5]));
654     __get_user(env->regwptr[WREG_O6], (&(*grp)[SPARC_MC_O6]));
655     __get_user(env->regwptr[WREG_O7], (&(*grp)[SPARC_MC_O7]));
656 
657     __get_user(env->regwptr[WREG_FP], &(ucp->tuc_mcontext.mc_fp));
658     __get_user(env->regwptr[WREG_I7], &(ucp->tuc_mcontext.mc_i7));
659 
660     fpup = &ucp->tuc_mcontext.mc_fpregs;
661 
662     __get_user(fenab, &(fpup->mcfpu_enab));
663     if (fenab) {
664         abi_ulong fprs;
665 
666         /*
667          * We use the FPRS from the guest only in deciding whether
668          * to restore the upper, lower, or both banks of the FPU regs.
669          * The kernel here writes the FPU register data into the
670          * process's current_thread_info state and unconditionally
671          * clears FPRS and TSTATE_PEF: this disables the FPU so that the
672          * next FPU-disabled trap will copy the data out of
673          * current_thread_info and into the real FPU registers.
674          * QEMU doesn't need to handle lazy-FPU-state-restoring like that,
675          * so we always load the data directly into the FPU registers
676          * and leave FPRS and TSTATE_PEF alone (so the FPU stays enabled).
677          * Note that because we (and the kernel) always write zeroes for
678          * the fenab and fprs in sparc64_get_context() none of this code
679          * will execute unless the guest manually constructed or changed
680          * the context structure.
681          */
682         __get_user(fprs, &(fpup->mcfpu_fprs));
683         if (fprs & FPRS_DL) {
684             for (i = 0; i < 16; i++) {
685                 __get_user(env->fpr[i].ll, &(fpup->mcfpu_fregs.dregs[i]));
686             }
687         }
688         if (fprs & FPRS_DU) {
689             for (i = 16; i < 32; i++) {
690                 __get_user(env->fpr[i].ll, &(fpup->mcfpu_fregs.dregs[i]));
691             }
692         }
693         __get_user(env->fsr, &(fpup->mcfpu_fsr));
694         __get_user(env->gsr, &(fpup->mcfpu_gsr));
695     }
696     unlock_user_struct(ucp, ucp_addr, 0);
697     return;
698 do_sigsegv:
699     unlock_user_struct(ucp, ucp_addr, 0);
700     force_sig(TARGET_SIGSEGV);
701 }
702 
703 void sparc64_get_context(CPUSPARCState *env)
704 {
705     abi_ulong ucp_addr;
706     struct target_ucontext *ucp;
707     target_mc_gregset_t *grp;
708     target_mcontext_t *mcp;
709     int err;
710     unsigned int i;
711     target_sigset_t target_set;
712     sigset_t set;
713 
714     ucp_addr = env->regwptr[WREG_O0];
715     if (!lock_user_struct(VERIFY_WRITE, ucp, ucp_addr, 0)) {
716         goto do_sigsegv;
717     }
718 
719     memset(ucp, 0, sizeof(*ucp));
720 
721     mcp = &ucp->tuc_mcontext;
722     grp = &mcp->mc_gregs;
723 
724     /* Skip over the trap instruction, first. */
725     env->pc = env->npc;
726     env->npc += 4;
727 
728     /* If we're only reading the signal mask then do_sigprocmask()
729      * is guaranteed not to fail, which is important because we don't
730      * have any way to signal a failure or restart this operation since
731      * this is not a normal syscall.
732      */
733     err = do_sigprocmask(0, NULL, &set);
734     assert(err == 0);
735     host_to_target_sigset_internal(&target_set, &set);
736     if (TARGET_NSIG_WORDS == 1) {
737         __put_user(target_set.sig[0],
738                    (abi_ulong *)&ucp->tuc_sigmask);
739     } else {
740         abi_ulong *src, *dst;
741         src = target_set.sig;
742         dst = ucp->tuc_sigmask.sig;
743         for (i = 0; i < TARGET_NSIG_WORDS; i++, dst++, src++) {
744             __put_user(*src, dst);
745         }
746     }
747 
748     __put_user(sparc64_tstate(env), &((*grp)[SPARC_MC_TSTATE]));
749     __put_user(env->pc, &((*grp)[SPARC_MC_PC]));
750     __put_user(env->npc, &((*grp)[SPARC_MC_NPC]));
751     __put_user(env->y, &((*grp)[SPARC_MC_Y]));
752     __put_user(env->gregs[1], &((*grp)[SPARC_MC_G1]));
753     __put_user(env->gregs[2], &((*grp)[SPARC_MC_G2]));
754     __put_user(env->gregs[3], &((*grp)[SPARC_MC_G3]));
755     __put_user(env->gregs[4], &((*grp)[SPARC_MC_G4]));
756     __put_user(env->gregs[5], &((*grp)[SPARC_MC_G5]));
757     __put_user(env->gregs[6], &((*grp)[SPARC_MC_G6]));
758     __put_user(env->gregs[7], &((*grp)[SPARC_MC_G7]));
759 
760     /*
761      * Note that unlike the kernel, we didn't need to mess with the
762      * guest register window state to save it into a pt_regs to run
763      * the kernel. So for us the guest's O regs are still in WREG_O*
764      * (unlike the kernel which has put them in UREG_I* in a pt_regs)
765      * and the fp and i7 are still in WREG_I6 and WREG_I7 and don't
766      * need to be fished out of userspace memory.
767      */
768     __put_user(env->regwptr[WREG_O0], &((*grp)[SPARC_MC_O0]));
769     __put_user(env->regwptr[WREG_O1], &((*grp)[SPARC_MC_O1]));
770     __put_user(env->regwptr[WREG_O2], &((*grp)[SPARC_MC_O2]));
771     __put_user(env->regwptr[WREG_O3], &((*grp)[SPARC_MC_O3]));
772     __put_user(env->regwptr[WREG_O4], &((*grp)[SPARC_MC_O4]));
773     __put_user(env->regwptr[WREG_O5], &((*grp)[SPARC_MC_O5]));
774     __put_user(env->regwptr[WREG_O6], &((*grp)[SPARC_MC_O6]));
775     __put_user(env->regwptr[WREG_O7], &((*grp)[SPARC_MC_O7]));
776 
777     __put_user(env->regwptr[WREG_FP], &(mcp->mc_fp));
778     __put_user(env->regwptr[WREG_I7], &(mcp->mc_i7));
779 
780     /*
781      * We don't write out the FPU state. This matches the kernel's
782      * implementation (which has the code for doing this but
783      * hidden behind an "if (fenab)" where fenab is always 0).
784      */
785 
786     unlock_user_struct(ucp, ucp_addr, 1);
787     return;
788 do_sigsegv:
789     unlock_user_struct(ucp, ucp_addr, 1);
790     force_sig(TARGET_SIGSEGV);
791 }
792 #endif /* TARGET_SPARC64 */
793