2 * Copyright (C) 2003 PathScale, Inc.
3 * Copyright (C) 2003 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4 * Licensed under the GPL
8 #include <linux/personality.h>
9 #include <linux/ptrace.h>
10 #include <linux/kernel.h>
11 #include <asm/unistd.h>
12 #include <asm/uaccess.h>
13 #include <asm/ucontext.h>
14 #include <frame_kern.h>
20 * FPU tag word conversions.
23 static inline unsigned short twd_i387_to_fxsr(unsigned short twd)
25 unsigned int tmp; /* to avoid 16 bit prefixes in the code */
27 /* Transform each pair of bits into 01 (valid) or 00 (empty) */
29 tmp = (tmp | (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */
30 /* and move the valid bits to the lower byte. */
31 tmp = (tmp | (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */
32 tmp = (tmp | (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */
33 tmp = (tmp | (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */
37 static inline unsigned long twd_fxsr_to_i387(struct user_fxsr_struct *fxsave)
39 struct _fpxreg *st = NULL;
40 unsigned long twd = (unsigned long) fxsave->twd;
42 unsigned long ret = 0xffff0000;
45 #define FPREG_ADDR(f, n) ((char *)&(f)->st_space + (n) * 16)
47 for (i = 0; i < 8; i++) {
49 st = (struct _fpxreg *) FPREG_ADDR(fxsave, i);
51 switch (st->exponent & 0x7fff) {
53 tag = 2; /* Special */
56 if ( !st->significand[0] &&
57 !st->significand[1] &&
58 !st->significand[2] &&
59 !st->significand[3] ) {
62 tag = 2; /* Special */
66 if (st->significand[3] & 0x8000) {
69 tag = 2; /* Special */
76 ret |= (tag << (2 * i));
82 static int convert_fxsr_to_user(struct _fpstate __user *buf,
83 struct user_fxsr_struct *fxsave)
86 struct _fpreg __user *to;
90 env[0] = (unsigned long)fxsave->cwd | 0xffff0000ul;
91 env[1] = (unsigned long)fxsave->swd | 0xffff0000ul;
92 env[2] = twd_fxsr_to_i387(fxsave);
94 env[4] = fxsave->fcs | ((unsigned long)fxsave->fop << 16);
98 if (__copy_to_user(buf, env, 7 * sizeof(unsigned long)))
102 from = (struct _fpxreg *) &fxsave->st_space[0];
103 for (i = 0; i < 8; i++, to++, from++) {
104 unsigned long __user *t = (unsigned long __user *)to;
105 unsigned long *f = (unsigned long *)from;
107 if (__put_user(*f, t) ||
108 __put_user(*(f + 1), t + 1) ||
109 __put_user(from->exponent, &to->exponent))
115 static int convert_fxsr_from_user(struct user_fxsr_struct *fxsave,
116 struct _fpstate __user *buf)
118 unsigned long env[7];
120 struct _fpreg __user *from;
123 if (copy_from_user( env, buf, 7 * sizeof(long)))
126 fxsave->cwd = (unsigned short)(env[0] & 0xffff);
127 fxsave->swd = (unsigned short)(env[1] & 0xffff);
128 fxsave->twd = twd_i387_to_fxsr((unsigned short)(env[2] & 0xffff));
129 fxsave->fip = env[3];
130 fxsave->fop = (unsigned short)((env[4] & 0xffff0000ul) >> 16);
131 fxsave->fcs = (env[4] & 0xffff);
132 fxsave->foo = env[5];
133 fxsave->fos = env[6];
135 to = (struct _fpxreg *) &fxsave->st_space[0];
137 for (i = 0; i < 8; i++, to++, from++) {
138 unsigned long *t = (unsigned long *)to;
139 unsigned long __user *f = (unsigned long __user *)from;
141 if (__get_user(*t, f) ||
142 __get_user(*(t + 1), f + 1) ||
143 __get_user(to->exponent, &from->exponent))
149 extern int have_fpx_regs;
153 static int copy_sc_from_user(struct pt_regs *regs,
154 struct sigcontext __user *from)
156 struct sigcontext sc;
159 /* Always make any pending restarted system calls return -EINTR */
160 current->restart_block.fn = do_no_restart_syscall;
162 err = copy_from_user(&sc, from, sizeof(sc));
166 #define GETREG(regno, regname) regs->regs.gp[HOST_##regno] = sc.regname
196 GETREG(EFLAGS, flags);
203 pid = userspace_pid[current_thread_info()->cpu];
206 struct user_fxsr_struct fpx;
208 err = copy_from_user(&fpx,
209 &((struct _fpstate __user *)sc.fpstate)->_fxsr_env[0],
210 sizeof(struct user_fxsr_struct));
214 err = convert_fxsr_from_user(&fpx, (void *)sc.fpstate);
218 err = restore_fpx_registers(pid, (unsigned long *) &fpx);
220 printk(KERN_ERR "copy_sc_from_user - "
221 "restore_fpx_registers failed, errno = %d\n",
228 err = copy_from_user(regs->regs.fp, (void *)sc.fpstate,
229 sizeof(struct _xstate));
236 static int copy_sc_to_user(struct sigcontext __user *to,
237 struct _xstate __user *to_fp, struct pt_regs *regs,
240 struct sigcontext sc;
241 struct faultinfo * fi = ¤t->thread.arch.faultinfo;
243 memset(&sc, 0, sizeof(struct sigcontext));
245 #define PUTREG(regno, regname) sc.regname = regs->regs.gp[HOST_##regno]
273 sc.err = fi->error_code;
274 sc.trapno = fi->trap_no;
277 PUTREG(EFLAGS, flags);
279 PUTREG(SP, sp_at_signal);
284 sc.fpstate = (unsigned long)to_fp;
286 err = copy_to_user(to, &sc, sizeof(struct sigcontext));
290 pid = userspace_pid[current_thread_info()->cpu];
294 struct user_fxsr_struct fpx;
296 err = save_fpx_registers(pid, (unsigned long *) &fpx);
298 printk(KERN_ERR "copy_sc_to_user - save_fpx_registers "
299 "failed, errno = %d\n", err);
303 err = convert_fxsr_to_user(&to_fp->fpstate, &fpx);
307 err |= __put_user(fpx.swd, &to_fp->fpstate.status);
308 err |= __put_user(X86_FXSR_MAGIC, &to_fp->fpstate.magic);
312 if (copy_to_user(&to_fp->fpstate._fxsr_env[0], &fpx,
313 sizeof(struct user_fxsr_struct)))
318 if (copy_to_user(to_fp, regs->regs.fp, sizeof(struct _xstate)))
326 static int copy_ucontext_to_user(struct ucontext __user *uc,
327 struct _xstate __user *fp, sigset_t *set,
332 err |= __save_altstack(&uc->uc_stack, sp);
333 err |= copy_sc_to_user(&uc->uc_mcontext, fp, ¤t->thread.regs, 0);
334 err |= copy_to_user(&uc->uc_sigmask, set, sizeof(*set));
340 char __user *pretcode;
342 struct sigcontext sc;
343 struct _xstate fpstate;
344 unsigned long extramask[_NSIG_WORDS-1];
350 char __user *pretcode;
352 struct siginfo __user *pinfo;
356 struct _xstate fpstate;
360 int setup_signal_stack_sc(unsigned long stack_top, struct ksignal *ksig,
361 struct pt_regs *regs, sigset_t *mask)
363 struct sigframe __user *frame;
364 void __user *restorer;
365 int err = 0, sig = ksig->sig;
367 /* This is the same calculation as i386 - ((sp + 4) & 15) == 0 */
368 stack_top = ((stack_top + 4) & -16UL) - 4;
369 frame = (struct sigframe __user *) stack_top - 1;
370 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
373 restorer = frame->retcode;
374 if (ksig->ka.sa.sa_flags & SA_RESTORER)
375 restorer = ksig->ka.sa.sa_restorer;
377 err |= __put_user(restorer, &frame->pretcode);
378 err |= __put_user(sig, &frame->sig);
379 err |= copy_sc_to_user(&frame->sc, &frame->fpstate, regs, mask->sig[0]);
381 err |= __copy_to_user(&frame->extramask, &mask->sig[1],
382 sizeof(frame->extramask));
385 * This is popl %eax ; movl $,%eax ; int $0x80
387 * WE DO NOT USE IT ANY MORE! It's only left here for historical
388 * reasons and because gdb uses it as a signature to notice
389 * signal handler stack frames.
391 err |= __put_user(0xb858, (short __user *)(frame->retcode+0));
392 err |= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2));
393 err |= __put_user(0x80cd, (short __user *)(frame->retcode+6));
398 PT_REGS_SP(regs) = (unsigned long) frame;
399 PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
400 PT_REGS_AX(regs) = (unsigned long) sig;
401 PT_REGS_DX(regs) = (unsigned long) 0;
402 PT_REGS_CX(regs) = (unsigned long) 0;
406 int setup_signal_stack_si(unsigned long stack_top, struct ksignal *ksig,
407 struct pt_regs *regs, sigset_t *mask)
409 struct rt_sigframe __user *frame;
410 void __user *restorer;
411 int err = 0, sig = ksig->sig;
414 frame = (struct rt_sigframe __user *) stack_top - 1;
415 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
418 restorer = frame->retcode;
419 if (ksig->ka.sa.sa_flags & SA_RESTORER)
420 restorer = ksig->ka.sa.sa_restorer;
422 err |= __put_user(restorer, &frame->pretcode);
423 err |= __put_user(sig, &frame->sig);
424 err |= __put_user(&frame->info, &frame->pinfo);
425 err |= __put_user(&frame->uc, &frame->puc);
426 err |= copy_siginfo_to_user(&frame->info, &ksig->info);
427 err |= copy_ucontext_to_user(&frame->uc, &frame->fpstate, mask,
431 * This is movl $,%eax ; int $0x80
433 * WE DO NOT USE IT ANY MORE! It's only left here for historical
434 * reasons and because gdb uses it as a signature to notice
435 * signal handler stack frames.
437 err |= __put_user(0xb8, (char __user *)(frame->retcode+0));
438 err |= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1));
439 err |= __put_user(0x80cd, (short __user *)(frame->retcode+5));
444 PT_REGS_SP(regs) = (unsigned long) frame;
445 PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
446 PT_REGS_AX(regs) = (unsigned long) sig;
447 PT_REGS_DX(regs) = (unsigned long) &frame->info;
448 PT_REGS_CX(regs) = (unsigned long) &frame->uc;
452 long sys_sigreturn(void)
454 unsigned long sp = PT_REGS_SP(¤t->thread.regs);
455 struct sigframe __user *frame = (struct sigframe __user *)(sp - 8);
457 struct sigcontext __user *sc = &frame->sc;
458 int sig_size = (_NSIG_WORDS - 1) * sizeof(unsigned long);
460 if (copy_from_user(&set.sig[0], &sc->oldmask, sizeof(set.sig[0])) ||
461 copy_from_user(&set.sig[1], frame->extramask, sig_size))
464 set_current_blocked(&set);
466 if (copy_sc_from_user(¤t->thread.regs, sc))
469 /* Avoid ERESTART handling */
470 PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1;
471 return PT_REGS_SYSCALL_RET(¤t->thread.regs);
474 force_sig(SIGSEGV, current);
482 char __user *pretcode;
485 struct _xstate fpstate;
488 int setup_signal_stack_si(unsigned long stack_top, struct ksignal *ksig,
489 struct pt_regs *regs, sigset_t *set)
491 struct rt_sigframe __user *frame;
492 int err = 0, sig = ksig->sig;
495 frame = (struct rt_sigframe __user *)
496 round_down(stack_top - sizeof(struct rt_sigframe), 16);
497 /* Subtract 128 for a red zone and 8 for proper alignment */
498 frame = (struct rt_sigframe __user *) ((unsigned long) frame - 128 - 8);
500 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
503 if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
504 err |= copy_siginfo_to_user(&frame->info, &ksig->info);
509 /* Create the ucontext. */
510 err |= __put_user(0, &frame->uc.uc_flags);
511 err |= __put_user(0, &frame->uc.uc_link);
512 err |= __save_altstack(&frame->uc.uc_stack, PT_REGS_SP(regs));
513 err |= copy_sc_to_user(&frame->uc.uc_mcontext, &frame->fpstate, regs,
516 fp_to = (unsigned long)&frame->fpstate;
518 err |= __put_user(fp_to, &frame->uc.uc_mcontext.fpstate);
519 if (sizeof(*set) == 16) {
520 err |= __put_user(set->sig[0], &frame->uc.uc_sigmask.sig[0]);
521 err |= __put_user(set->sig[1], &frame->uc.uc_sigmask.sig[1]);
524 err |= __copy_to_user(&frame->uc.uc_sigmask, set,
528 * Set up to return from userspace. If provided, use a stub
529 * already in userspace.
531 /* x86-64 should always use SA_RESTORER. */
532 if (ksig->ka.sa.sa_flags & SA_RESTORER)
533 err |= __put_user((void *)ksig->ka.sa.sa_restorer,
536 /* could use a vstub here */
542 PT_REGS_SP(regs) = (unsigned long) frame;
543 PT_REGS_DI(regs) = sig;
544 /* In case the signal handler was declared without prototypes */
545 PT_REGS_AX(regs) = 0;
548 * This also works for non SA_SIGINFO handlers because they expect the
549 * next argument after the signal number on the stack.
551 PT_REGS_SI(regs) = (unsigned long) &frame->info;
552 PT_REGS_DX(regs) = (unsigned long) &frame->uc;
553 PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
559 long sys_rt_sigreturn(void)
561 unsigned long sp = PT_REGS_SP(¤t->thread.regs);
562 struct rt_sigframe __user *frame =
563 (struct rt_sigframe __user *)(sp - sizeof(long));
564 struct ucontext __user *uc = &frame->uc;
567 if (copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
570 set_current_blocked(&set);
572 if (copy_sc_from_user(¤t->thread.regs, &uc->uc_mcontext))
575 /* Avoid ERESTART handling */
576 PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1;
577 return PT_REGS_SYSCALL_RET(¤t->thread.regs);
580 force_sig(SIGSEGV, current);