xref: /openbmc/qemu/linux-user/sparc/signal.c (revision 3cda299d)
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     env->psr = (psr & PSR_ICC) | (env->psr & ~PSR_ICC);
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 void setup_frame(int sig, struct target_sigaction *ka,
246                  target_sigset_t *set, CPUSPARCState *env)
247 {
248     abi_ulong sf_addr;
249     struct target_signal_frame *sf;
250     size_t sf_size = sizeof(*sf) + sizeof(struct target_siginfo_fpu);
251     int i;
252 
253     sf_addr = get_sigframe(ka, env, sf_size);
254     trace_user_setup_frame(env, sf_addr);
255 
256     sf = lock_user(VERIFY_WRITE, sf_addr, sf_size, 0);
257     if (!sf) {
258         force_sigsegv(sig);
259         return;
260     }
261 
262     /* 2. Save the current process state */
263     save_pt_regs(&sf->regs, env);
264     __put_user(0, &sf->extra_size);
265 
266     save_fpu((struct target_siginfo_fpu *)(sf + 1), env);
267     __put_user(sf_addr + sizeof(*sf), &sf->fpu_save);
268 
269     __put_user(0, &sf->rwin_save);  /* TODO: save_rwin_state */
270 
271     __put_user(set->sig[0], &sf->si_mask);
272     for (i = 0; i < TARGET_NSIG_WORDS - 1; i++) {
273         __put_user(set->sig[i + 1], &sf->extramask[i]);
274     }
275 
276     save_reg_win(&sf->ss.win, env);
277 
278     /* 3. signal handler back-trampoline and parameters */
279     env->regwptr[WREG_SP] = sf_addr;
280     env->regwptr[WREG_O0] = sig;
281     env->regwptr[WREG_O1] = sf_addr +
282             offsetof(struct target_signal_frame, regs);
283     env->regwptr[WREG_O2] = sf_addr +
284             offsetof(struct target_signal_frame, regs);
285 
286     /* 4. signal handler */
287     env->pc = ka->_sa_handler;
288     env->npc = env->pc + 4;
289 
290     /* 5. return to kernel instructions */
291     if (ka->ka_restorer) {
292         env->regwptr[WREG_O7] = ka->ka_restorer;
293     } else {
294         env->regwptr[WREG_O7] = sf_addr +
295                 offsetof(struct target_signal_frame, insns) - 2 * 4;
296 
297         /* mov __NR_sigreturn, %g1 */
298         __put_user(0x821020d8u, &sf->insns[0]);
299         /* t 0x10 */
300         __put_user(0x91d02010u, &sf->insns[1]);
301     }
302     unlock_user(sf, sf_addr, sf_size);
303 }
304 #endif /* TARGET_ARCH_HAS_SETUP_FRAME */
305 
306 void setup_rt_frame(int sig, struct target_sigaction *ka,
307                     target_siginfo_t *info,
308                     target_sigset_t *set, CPUSPARCState *env)
309 {
310     abi_ulong sf_addr;
311     struct target_rt_signal_frame *sf;
312     size_t sf_size = sizeof(*sf) + sizeof(struct target_siginfo_fpu);
313 
314     sf_addr = get_sigframe(ka, env, sf_size);
315     trace_user_setup_rt_frame(env, sf_addr);
316 
317     sf = lock_user(VERIFY_WRITE, sf_addr, sf_size, 0);
318     if (!sf) {
319         force_sigsegv(sig);
320         return;
321     }
322 
323     /* 2. Save the current process state */
324     save_reg_win(&sf->ss.win, env);
325     save_pt_regs(&sf->regs, env);
326 
327     save_fpu((struct target_siginfo_fpu *)(sf + 1), env);
328     __put_user(sf_addr + sizeof(*sf), &sf->fpu_save);
329 
330     __put_user(0, &sf->rwin_save);  /* TODO: save_rwin_state */
331 
332     tswap_siginfo(&sf->info, info);
333     tswap_sigset(&sf->mask, set);
334     target_save_altstack(&sf->stack, env);
335 
336 #ifdef TARGET_ABI32
337     __put_user(0, &sf->extra_size);
338 #endif
339 
340     /* 3. signal handler back-trampoline and parameters */
341     env->regwptr[WREG_SP] = sf_addr - TARGET_STACK_BIAS;
342     env->regwptr[WREG_O0] = sig;
343     env->regwptr[WREG_O1] =
344         sf_addr + offsetof(struct target_rt_signal_frame, info);
345 #ifdef TARGET_ABI32
346     env->regwptr[WREG_O2] =
347         sf_addr + offsetof(struct target_rt_signal_frame, regs);
348 #else
349     env->regwptr[WREG_O2] = env->regwptr[WREG_O1];
350 #endif
351 
352     /* 4. signal handler */
353     env->pc = ka->_sa_handler;
354     env->npc = env->pc + 4;
355 
356     /* 5. return to kernel instructions */
357 #ifdef TARGET_ABI32
358     if (ka->ka_restorer) {
359         env->regwptr[WREG_O7] = ka->ka_restorer;
360     } else {
361         env->regwptr[WREG_O7] =
362             sf_addr + offsetof(struct target_rt_signal_frame, insns) - 2 * 4;
363 
364         /* mov __NR_rt_sigreturn, %g1 */
365         __put_user(0x82102065u, &sf->insns[0]);
366         /* t 0x10 */
367         __put_user(0x91d02010u, &sf->insns[1]);
368     }
369 #else
370     env->regwptr[WREG_O7] = ka->ka_restorer;
371 #endif
372 
373     unlock_user(sf, sf_addr, sf_size);
374 }
375 
376 long do_sigreturn(CPUSPARCState *env)
377 {
378 #ifdef TARGET_ARCH_HAS_SETUP_FRAME
379     abi_ulong sf_addr;
380     struct target_signal_frame *sf = NULL;
381     abi_ulong pc, npc, ptr;
382     target_sigset_t set;
383     sigset_t host_set;
384     int i;
385 
386     sf_addr = env->regwptr[WREG_SP];
387     trace_user_do_sigreturn(env, sf_addr);
388 
389     /* 1. Make sure we are not getting garbage from the user */
390     if ((sf_addr & 15) || !lock_user_struct(VERIFY_READ, sf, sf_addr, 1)) {
391         goto segv_and_exit;
392     }
393 
394     /* Make sure stack pointer is aligned.  */
395     __get_user(ptr, &sf->regs.u_regs[14]);
396     if (ptr & 7) {
397         goto segv_and_exit;
398     }
399 
400     /* Make sure instruction pointers are aligned.  */
401     __get_user(pc, &sf->regs.pc);
402     __get_user(npc, &sf->regs.npc);
403     if ((pc | npc) & 3) {
404         goto segv_and_exit;
405     }
406 
407     /* 2. Restore the state */
408     restore_pt_regs(&sf->regs, env);
409     env->pc = pc;
410     env->npc = npc;
411 
412     __get_user(ptr, &sf->fpu_save);
413     if (ptr) {
414         struct target_siginfo_fpu *fpu;
415         if ((ptr & 3) || !lock_user_struct(VERIFY_READ, fpu, ptr, 1)) {
416             goto segv_and_exit;
417         }
418         restore_fpu(fpu, env);
419         unlock_user_struct(fpu, ptr, 0);
420     }
421 
422     __get_user(ptr, &sf->rwin_save);
423     if (ptr) {
424         goto segv_and_exit;  /* TODO: restore_rwin */
425     }
426 
427     __get_user(set.sig[0], &sf->si_mask);
428     for (i = 1; i < TARGET_NSIG_WORDS; i++) {
429         __get_user(set.sig[i], &sf->extramask[i - 1]);
430     }
431 
432     target_to_host_sigset_internal(&host_set, &set);
433     set_sigmask(&host_set);
434 
435     unlock_user_struct(sf, sf_addr, 0);
436     return -TARGET_QEMU_ESIGRETURN;
437 
438  segv_and_exit:
439     unlock_user_struct(sf, sf_addr, 0);
440     force_sig(TARGET_SIGSEGV);
441     return -TARGET_QEMU_ESIGRETURN;
442 #else
443     return -TARGET_ENOSYS;
444 #endif
445 }
446 
447 long do_rt_sigreturn(CPUSPARCState *env)
448 {
449     abi_ulong sf_addr, tpc, tnpc, ptr;
450     struct target_rt_signal_frame *sf = NULL;
451     sigset_t set;
452 
453     sf_addr = get_sp_from_cpustate(env);
454     trace_user_do_rt_sigreturn(env, sf_addr);
455 
456     /* 1. Make sure we are not getting garbage from the user */
457     if ((sf_addr & 15) || !lock_user_struct(VERIFY_READ, sf, sf_addr, 1)) {
458         goto segv_and_exit;
459     }
460 
461     /* Validate SP alignment.  */
462     __get_user(ptr, &sf->regs.u_regs[8 + WREG_SP]);
463     if ((ptr + TARGET_STACK_BIAS) & 7) {
464         goto segv_and_exit;
465     }
466 
467     /* Validate PC and NPC alignment.  */
468     __get_user(tpc, &sf->regs.pc);
469     __get_user(tnpc, &sf->regs.npc);
470     if ((tpc | tnpc) & 3) {
471         goto segv_and_exit;
472     }
473 
474     /* 2. Restore the state */
475     restore_pt_regs(&sf->regs, env);
476 
477     __get_user(ptr, &sf->fpu_save);
478     if (ptr) {
479         struct target_siginfo_fpu *fpu;
480         if ((ptr & 7) || !lock_user_struct(VERIFY_READ, fpu, ptr, 1)) {
481             goto segv_and_exit;
482         }
483         restore_fpu(fpu, env);
484         unlock_user_struct(fpu, ptr, 0);
485     }
486 
487     __get_user(ptr, &sf->rwin_save);
488     if (ptr) {
489         goto segv_and_exit;  /* TODO: restore_rwin_state */
490     }
491 
492     target_restore_altstack(&sf->stack, env);
493     target_to_host_sigset(&set, &sf->mask);
494     set_sigmask(&set);
495 
496     env->pc = tpc;
497     env->npc = tnpc;
498 
499     unlock_user_struct(sf, sf_addr, 0);
500     return -TARGET_QEMU_ESIGRETURN;
501 
502  segv_and_exit:
503     unlock_user_struct(sf, sf_addr, 0);
504     force_sig(TARGET_SIGSEGV);
505     return -TARGET_QEMU_ESIGRETURN;
506 }
507 
508 #if defined(TARGET_SPARC64) && !defined(TARGET_ABI32)
509 #define SPARC_MC_TSTATE 0
510 #define SPARC_MC_PC 1
511 #define SPARC_MC_NPC 2
512 #define SPARC_MC_Y 3
513 #define SPARC_MC_G1 4
514 #define SPARC_MC_G2 5
515 #define SPARC_MC_G3 6
516 #define SPARC_MC_G4 7
517 #define SPARC_MC_G5 8
518 #define SPARC_MC_G6 9
519 #define SPARC_MC_G7 10
520 #define SPARC_MC_O0 11
521 #define SPARC_MC_O1 12
522 #define SPARC_MC_O2 13
523 #define SPARC_MC_O3 14
524 #define SPARC_MC_O4 15
525 #define SPARC_MC_O5 16
526 #define SPARC_MC_O6 17
527 #define SPARC_MC_O7 18
528 #define SPARC_MC_NGREG 19
529 
530 typedef abi_ulong target_mc_greg_t;
531 typedef target_mc_greg_t target_mc_gregset_t[SPARC_MC_NGREG];
532 
533 struct target_mc_fq {
534     abi_ulong mcfq_addr;
535     uint32_t mcfq_insn;
536 };
537 
538 /*
539  * Note the manual 16-alignment; the kernel gets this because it
540  * includes a "long double qregs[16]" in the mcpu_fregs union,
541  * which we can't do.
542  */
543 struct target_mc_fpu {
544     union {
545         uint32_t sregs[32];
546         uint64_t dregs[32];
547         //uint128_t qregs[16];
548     } mcfpu_fregs;
549     abi_ulong mcfpu_fsr;
550     abi_ulong mcfpu_fprs;
551     abi_ulong mcfpu_gsr;
552     abi_ulong mcfpu_fq;
553     unsigned char mcfpu_qcnt;
554     unsigned char mcfpu_qentsz;
555     unsigned char mcfpu_enab;
556 } __attribute__((aligned(16)));
557 typedef struct target_mc_fpu target_mc_fpu_t;
558 
559 typedef struct {
560     target_mc_gregset_t mc_gregs;
561     target_mc_greg_t mc_fp;
562     target_mc_greg_t mc_i7;
563     target_mc_fpu_t mc_fpregs;
564 } target_mcontext_t;
565 
566 struct target_ucontext {
567     abi_ulong tuc_link;
568     abi_ulong tuc_flags;
569     target_sigset_t tuc_sigmask;
570     target_mcontext_t tuc_mcontext;
571 };
572 
573 /* {set, get}context() needed for 64-bit SparcLinux userland. */
574 void sparc64_set_context(CPUSPARCState *env)
575 {
576     abi_ulong ucp_addr;
577     struct target_ucontext *ucp;
578     target_mc_gregset_t *grp;
579     target_mc_fpu_t *fpup;
580     abi_ulong pc, npc, tstate;
581     unsigned int i;
582     unsigned char fenab;
583 
584     ucp_addr = env->regwptr[WREG_O0];
585     if (!lock_user_struct(VERIFY_READ, ucp, ucp_addr, 1)) {
586         goto do_sigsegv;
587     }
588     grp  = &ucp->tuc_mcontext.mc_gregs;
589     __get_user(pc, &((*grp)[SPARC_MC_PC]));
590     __get_user(npc, &((*grp)[SPARC_MC_NPC]));
591     if ((pc | npc) & 3) {
592         goto do_sigsegv;
593     }
594     if (env->regwptr[WREG_O1]) {
595         target_sigset_t target_set;
596         sigset_t set;
597 
598         if (TARGET_NSIG_WORDS == 1) {
599             __get_user(target_set.sig[0], &ucp->tuc_sigmask.sig[0]);
600         } else {
601             abi_ulong *src, *dst;
602             src = ucp->tuc_sigmask.sig;
603             dst = target_set.sig;
604             for (i = 0; i < TARGET_NSIG_WORDS; i++, dst++, src++) {
605                 __get_user(*dst, src);
606             }
607         }
608         target_to_host_sigset_internal(&set, &target_set);
609         set_sigmask(&set);
610     }
611     env->pc = pc;
612     env->npc = npc;
613     __get_user(env->y, &((*grp)[SPARC_MC_Y]));
614     __get_user(tstate, &((*grp)[SPARC_MC_TSTATE]));
615     /* Honour TSTATE_ASI, TSTATE_ICC and TSTATE_XCC only */
616     env->asi = (tstate >> 24) & 0xff;
617     cpu_put_ccr(env, (tstate >> 32) & 0xff);
618     __get_user(env->gregs[1], (&(*grp)[SPARC_MC_G1]));
619     __get_user(env->gregs[2], (&(*grp)[SPARC_MC_G2]));
620     __get_user(env->gregs[3], (&(*grp)[SPARC_MC_G3]));
621     __get_user(env->gregs[4], (&(*grp)[SPARC_MC_G4]));
622     __get_user(env->gregs[5], (&(*grp)[SPARC_MC_G5]));
623     __get_user(env->gregs[6], (&(*grp)[SPARC_MC_G6]));
624     /* Skip g7 as that's the thread register in userspace */
625 
626     /*
627      * Note that unlike the kernel, we didn't need to mess with the
628      * guest register window state to save it into a pt_regs to run
629      * the kernel. So for us the guest's O regs are still in WREG_O*
630      * (unlike the kernel which has put them in UREG_I* in a pt_regs)
631      * and the fp and i7 are still in WREG_I6 and WREG_I7 and don't
632      * need to be written back to userspace memory.
633      */
634     __get_user(env->regwptr[WREG_O0], (&(*grp)[SPARC_MC_O0]));
635     __get_user(env->regwptr[WREG_O1], (&(*grp)[SPARC_MC_O1]));
636     __get_user(env->regwptr[WREG_O2], (&(*grp)[SPARC_MC_O2]));
637     __get_user(env->regwptr[WREG_O3], (&(*grp)[SPARC_MC_O3]));
638     __get_user(env->regwptr[WREG_O4], (&(*grp)[SPARC_MC_O4]));
639     __get_user(env->regwptr[WREG_O5], (&(*grp)[SPARC_MC_O5]));
640     __get_user(env->regwptr[WREG_O6], (&(*grp)[SPARC_MC_O6]));
641     __get_user(env->regwptr[WREG_O7], (&(*grp)[SPARC_MC_O7]));
642 
643     __get_user(env->regwptr[WREG_FP], &(ucp->tuc_mcontext.mc_fp));
644     __get_user(env->regwptr[WREG_I7], &(ucp->tuc_mcontext.mc_i7));
645 
646     fpup = &ucp->tuc_mcontext.mc_fpregs;
647 
648     __get_user(fenab, &(fpup->mcfpu_enab));
649     if (fenab) {
650         abi_ulong fprs;
651 
652         /*
653          * We use the FPRS from the guest only in deciding whether
654          * to restore the upper, lower, or both banks of the FPU regs.
655          * The kernel here writes the FPU register data into the
656          * process's current_thread_info state and unconditionally
657          * clears FPRS and TSTATE_PEF: this disables the FPU so that the
658          * next FPU-disabled trap will copy the data out of
659          * current_thread_info and into the real FPU registers.
660          * QEMU doesn't need to handle lazy-FPU-state-restoring like that,
661          * so we always load the data directly into the FPU registers
662          * and leave FPRS and TSTATE_PEF alone (so the FPU stays enabled).
663          * Note that because we (and the kernel) always write zeroes for
664          * the fenab and fprs in sparc64_get_context() none of this code
665          * will execute unless the guest manually constructed or changed
666          * the context structure.
667          */
668         __get_user(fprs, &(fpup->mcfpu_fprs));
669         if (fprs & FPRS_DL) {
670             for (i = 0; i < 16; i++) {
671                 __get_user(env->fpr[i].ll, &(fpup->mcfpu_fregs.dregs[i]));
672             }
673         }
674         if (fprs & FPRS_DU) {
675             for (i = 16; i < 32; i++) {
676                 __get_user(env->fpr[i].ll, &(fpup->mcfpu_fregs.dregs[i]));
677             }
678         }
679         __get_user(env->fsr, &(fpup->mcfpu_fsr));
680         __get_user(env->gsr, &(fpup->mcfpu_gsr));
681     }
682     unlock_user_struct(ucp, ucp_addr, 0);
683     return;
684 do_sigsegv:
685     unlock_user_struct(ucp, ucp_addr, 0);
686     force_sig(TARGET_SIGSEGV);
687 }
688 
689 void sparc64_get_context(CPUSPARCState *env)
690 {
691     abi_ulong ucp_addr;
692     struct target_ucontext *ucp;
693     target_mc_gregset_t *grp;
694     target_mcontext_t *mcp;
695     int err;
696     unsigned int i;
697     target_sigset_t target_set;
698     sigset_t set;
699 
700     ucp_addr = env->regwptr[WREG_O0];
701     if (!lock_user_struct(VERIFY_WRITE, ucp, ucp_addr, 0)) {
702         goto do_sigsegv;
703     }
704 
705     memset(ucp, 0, sizeof(*ucp));
706 
707     mcp = &ucp->tuc_mcontext;
708     grp = &mcp->mc_gregs;
709 
710     /* Skip over the trap instruction, first. */
711     env->pc = env->npc;
712     env->npc += 4;
713 
714     /* If we're only reading the signal mask then do_sigprocmask()
715      * is guaranteed not to fail, which is important because we don't
716      * have any way to signal a failure or restart this operation since
717      * this is not a normal syscall.
718      */
719     err = do_sigprocmask(0, NULL, &set);
720     assert(err == 0);
721     host_to_target_sigset_internal(&target_set, &set);
722     if (TARGET_NSIG_WORDS == 1) {
723         __put_user(target_set.sig[0],
724                    (abi_ulong *)&ucp->tuc_sigmask);
725     } else {
726         abi_ulong *src, *dst;
727         src = target_set.sig;
728         dst = ucp->tuc_sigmask.sig;
729         for (i = 0; i < TARGET_NSIG_WORDS; i++, dst++, src++) {
730             __put_user(*src, dst);
731         }
732     }
733 
734     __put_user(sparc64_tstate(env), &((*grp)[SPARC_MC_TSTATE]));
735     __put_user(env->pc, &((*grp)[SPARC_MC_PC]));
736     __put_user(env->npc, &((*grp)[SPARC_MC_NPC]));
737     __put_user(env->y, &((*grp)[SPARC_MC_Y]));
738     __put_user(env->gregs[1], &((*grp)[SPARC_MC_G1]));
739     __put_user(env->gregs[2], &((*grp)[SPARC_MC_G2]));
740     __put_user(env->gregs[3], &((*grp)[SPARC_MC_G3]));
741     __put_user(env->gregs[4], &((*grp)[SPARC_MC_G4]));
742     __put_user(env->gregs[5], &((*grp)[SPARC_MC_G5]));
743     __put_user(env->gregs[6], &((*grp)[SPARC_MC_G6]));
744     __put_user(env->gregs[7], &((*grp)[SPARC_MC_G7]));
745 
746     /*
747      * Note that unlike the kernel, we didn't need to mess with the
748      * guest register window state to save it into a pt_regs to run
749      * the kernel. So for us the guest's O regs are still in WREG_O*
750      * (unlike the kernel which has put them in UREG_I* in a pt_regs)
751      * and the fp and i7 are still in WREG_I6 and WREG_I7 and don't
752      * need to be fished out of userspace memory.
753      */
754     __put_user(env->regwptr[WREG_O0], &((*grp)[SPARC_MC_O0]));
755     __put_user(env->regwptr[WREG_O1], &((*grp)[SPARC_MC_O1]));
756     __put_user(env->regwptr[WREG_O2], &((*grp)[SPARC_MC_O2]));
757     __put_user(env->regwptr[WREG_O3], &((*grp)[SPARC_MC_O3]));
758     __put_user(env->regwptr[WREG_O4], &((*grp)[SPARC_MC_O4]));
759     __put_user(env->regwptr[WREG_O5], &((*grp)[SPARC_MC_O5]));
760     __put_user(env->regwptr[WREG_O6], &((*grp)[SPARC_MC_O6]));
761     __put_user(env->regwptr[WREG_O7], &((*grp)[SPARC_MC_O7]));
762 
763     __put_user(env->regwptr[WREG_FP], &(mcp->mc_fp));
764     __put_user(env->regwptr[WREG_I7], &(mcp->mc_i7));
765 
766     /*
767      * We don't write out the FPU state. This matches the kernel's
768      * implementation (which has the code for doing this but
769      * hidden behind an "if (fenab)" where fenab is always 0).
770      */
771 
772     unlock_user_struct(ucp, ucp_addr, 1);
773     return;
774 do_sigsegv:
775     unlock_user_struct(ucp, ucp_addr, 1);
776     force_sig(TARGET_SIGSEGV);
777 }
778 #endif
779