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 <linux/syscalls.h>
12 #include <asm/unistd.h>
13 #include <linux/uaccess.h>
14 #include <asm/ucontext.h>
15 #include <frame_kern.h>
16 #include <registers.h>
22 * FPU tag word conversions.
25 static inline unsigned short twd_i387_to_fxsr(unsigned short twd)
27 unsigned int tmp; /* to avoid 16 bit prefixes in the code */
29 /* Transform each pair of bits into 01 (valid) or 00 (empty) */
31 tmp = (tmp | (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */
32 /* and move the valid bits to the lower byte. */
33 tmp = (tmp | (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */
34 tmp = (tmp | (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */
35 tmp = (tmp | (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */
39 static inline unsigned long twd_fxsr_to_i387(struct user_fxsr_struct *fxsave)
41 struct _fpxreg *st = NULL;
42 unsigned long twd = (unsigned long) fxsave->twd;
44 unsigned long ret = 0xffff0000;
47 #define FPREG_ADDR(f, n) ((char *)&(f)->st_space + (n) * 16)
49 for (i = 0; i < 8; i++) {
51 st = (struct _fpxreg *) FPREG_ADDR(fxsave, i);
53 switch (st->exponent & 0x7fff) {
55 tag = 2; /* Special */
58 if ( !st->significand[0] &&
59 !st->significand[1] &&
60 !st->significand[2] &&
61 !st->significand[3] ) {
64 tag = 2; /* Special */
68 if (st->significand[3] & 0x8000) {
71 tag = 2; /* Special */
78 ret |= (tag << (2 * i));
84 static int convert_fxsr_to_user(struct _fpstate __user *buf,
85 struct user_fxsr_struct *fxsave)
88 struct _fpreg __user *to;
92 env[0] = (unsigned long)fxsave->cwd | 0xffff0000ul;
93 env[1] = (unsigned long)fxsave->swd | 0xffff0000ul;
94 env[2] = twd_fxsr_to_i387(fxsave);
96 env[4] = fxsave->fcs | ((unsigned long)fxsave->fop << 16);
100 if (__copy_to_user(buf, env, 7 * sizeof(unsigned long)))
104 from = (struct _fpxreg *) &fxsave->st_space[0];
105 for (i = 0; i < 8; i++, to++, from++) {
106 unsigned long __user *t = (unsigned long __user *)to;
107 unsigned long *f = (unsigned long *)from;
109 if (__put_user(*f, t) ||
110 __put_user(*(f + 1), t + 1) ||
111 __put_user(from->exponent, &to->exponent))
117 static int convert_fxsr_from_user(struct user_fxsr_struct *fxsave,
118 struct _fpstate __user *buf)
120 unsigned long env[7];
122 struct _fpreg __user *from;
125 if (copy_from_user( env, buf, 7 * sizeof(long)))
128 fxsave->cwd = (unsigned short)(env[0] & 0xffff);
129 fxsave->swd = (unsigned short)(env[1] & 0xffff);
130 fxsave->twd = twd_i387_to_fxsr((unsigned short)(env[2] & 0xffff));
131 fxsave->fip = env[3];
132 fxsave->fop = (unsigned short)((env[4] & 0xffff0000ul) >> 16);
133 fxsave->fcs = (env[4] & 0xffff);
134 fxsave->foo = env[5];
135 fxsave->fos = env[6];
137 to = (struct _fpxreg *) &fxsave->st_space[0];
139 for (i = 0; i < 8; i++, to++, from++) {
140 unsigned long *t = (unsigned long *)to;
141 unsigned long __user *f = (unsigned long __user *)from;
143 if (__get_user(*t, f) ||
144 __get_user(*(t + 1), f + 1) ||
145 __get_user(to->exponent, &from->exponent))
151 extern int have_fpx_regs;
155 static int copy_sc_from_user(struct pt_regs *regs,
156 struct sigcontext __user *from)
158 struct sigcontext sc;
161 /* Always make any pending restarted system calls return -EINTR */
162 current->restart_block.fn = do_no_restart_syscall;
164 err = copy_from_user(&sc, from, sizeof(sc));
168 #define GETREG(regno, regname) regs->regs.gp[HOST_##regno] = sc.regname
198 GETREG(EFLAGS, flags);
207 struct user_fxsr_struct fpx;
208 int pid = userspace_pid[current_thread_info()->cpu];
210 err = copy_from_user(&fpx,
211 &((struct _fpstate __user *)sc.fpstate)->_fxsr_env[0],
212 sizeof(struct user_fxsr_struct));
216 err = convert_fxsr_from_user(&fpx, (void *)sc.fpstate);
220 err = restore_fpx_registers(pid, (unsigned long *) &fpx);
222 printk(KERN_ERR "copy_sc_from_user - "
223 "restore_fpx_registers failed, errno = %d\n",
230 err = copy_from_user(regs->regs.fp, (void *)sc.fpstate,
231 sizeof(struct _xstate));
238 static int copy_sc_to_user(struct sigcontext __user *to,
239 struct _xstate __user *to_fp, struct pt_regs *regs,
242 struct sigcontext sc;
243 struct faultinfo * fi = ¤t->thread.arch.faultinfo;
245 memset(&sc, 0, sizeof(struct sigcontext));
247 #define PUTREG(regno, regname) sc.regname = regs->regs.gp[HOST_##regno]
275 sc.err = fi->error_code;
276 sc.trapno = fi->trap_no;
279 PUTREG(EFLAGS, flags);
281 PUTREG(SP, sp_at_signal);
286 sc.fpstate = (unsigned long)to_fp;
288 err = copy_to_user(to, &sc, sizeof(struct sigcontext));
294 int pid = userspace_pid[current_thread_info()->cpu];
295 struct user_fxsr_struct fpx;
297 err = save_fpx_registers(pid, (unsigned long *) &fpx);
299 printk(KERN_ERR "copy_sc_to_user - save_fpx_registers "
300 "failed, errno = %d\n", err);
304 err = convert_fxsr_to_user(&to_fp->fpstate, &fpx);
308 err |= __put_user(fpx.swd, &to_fp->fpstate.status);
309 err |= __put_user(X86_FXSR_MAGIC, &to_fp->fpstate.magic);
313 if (copy_to_user(&to_fp->fpstate._fxsr_env[0], &fpx,
314 sizeof(struct user_fxsr_struct)))
319 if (copy_to_user(to_fp, regs->regs.fp, sizeof(struct _xstate)))
327 static int copy_ucontext_to_user(struct ucontext __user *uc,
328 struct _xstate __user *fp, sigset_t *set,
333 err |= __save_altstack(&uc->uc_stack, sp);
334 err |= copy_sc_to_user(&uc->uc_mcontext, fp, ¤t->thread.regs, 0);
335 err |= copy_to_user(&uc->uc_sigmask, set, sizeof(*set));
341 char __user *pretcode;
343 struct sigcontext sc;
344 struct _xstate fpstate;
345 unsigned long extramask[_NSIG_WORDS-1];
351 char __user *pretcode;
353 struct siginfo __user *pinfo;
357 struct _xstate fpstate;
361 int setup_signal_stack_sc(unsigned long stack_top, struct ksignal *ksig,
362 struct pt_regs *regs, sigset_t *mask)
364 struct sigframe __user *frame;
365 void __user *restorer;
366 int err = 0, sig = ksig->sig;
368 /* This is the same calculation as i386 - ((sp + 4) & 15) == 0 */
369 stack_top = ((stack_top + 4) & -16UL) - 4;
370 frame = (struct sigframe __user *) stack_top - 1;
371 if (!access_ok(frame, sizeof(*frame)))
374 restorer = frame->retcode;
375 if (ksig->ka.sa.sa_flags & SA_RESTORER)
376 restorer = ksig->ka.sa.sa_restorer;
378 err |= __put_user(restorer, &frame->pretcode);
379 err |= __put_user(sig, &frame->sig);
380 err |= copy_sc_to_user(&frame->sc, &frame->fpstate, regs, mask->sig[0]);
382 err |= __copy_to_user(&frame->extramask, &mask->sig[1],
383 sizeof(frame->extramask));
386 * This is popl %eax ; movl $,%eax ; int $0x80
388 * WE DO NOT USE IT ANY MORE! It's only left here for historical
389 * reasons and because gdb uses it as a signature to notice
390 * signal handler stack frames.
392 err |= __put_user(0xb858, (short __user *)(frame->retcode+0));
393 err |= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2));
394 err |= __put_user(0x80cd, (short __user *)(frame->retcode+6));
399 PT_REGS_SP(regs) = (unsigned long) frame;
400 PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
401 PT_REGS_AX(regs) = (unsigned long) sig;
402 PT_REGS_DX(regs) = (unsigned long) 0;
403 PT_REGS_CX(regs) = (unsigned long) 0;
407 int setup_signal_stack_si(unsigned long stack_top, struct ksignal *ksig,
408 struct pt_regs *regs, sigset_t *mask)
410 struct rt_sigframe __user *frame;
411 void __user *restorer;
412 int err = 0, sig = ksig->sig;
415 frame = (struct rt_sigframe __user *) stack_top - 1;
416 if (!access_ok(frame, sizeof(*frame)))
419 restorer = frame->retcode;
420 if (ksig->ka.sa.sa_flags & SA_RESTORER)
421 restorer = ksig->ka.sa.sa_restorer;
423 err |= __put_user(restorer, &frame->pretcode);
424 err |= __put_user(sig, &frame->sig);
425 err |= __put_user(&frame->info, &frame->pinfo);
426 err |= __put_user(&frame->uc, &frame->puc);
427 err |= copy_siginfo_to_user(&frame->info, &ksig->info);
428 err |= copy_ucontext_to_user(&frame->uc, &frame->fpstate, mask,
432 * This is movl $,%eax ; int $0x80
434 * WE DO NOT USE IT ANY MORE! It's only left here for historical
435 * reasons and because gdb uses it as a signature to notice
436 * signal handler stack frames.
438 err |= __put_user(0xb8, (char __user *)(frame->retcode+0));
439 err |= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1));
440 err |= __put_user(0x80cd, (short __user *)(frame->retcode+5));
445 PT_REGS_SP(regs) = (unsigned long) frame;
446 PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
447 PT_REGS_AX(regs) = (unsigned long) sig;
448 PT_REGS_DX(regs) = (unsigned long) &frame->info;
449 PT_REGS_CX(regs) = (unsigned long) &frame->uc;
453 SYSCALL_DEFINE0(sigreturn)
455 unsigned long sp = PT_REGS_SP(¤t->thread.regs);
456 struct sigframe __user *frame = (struct sigframe __user *)(sp - 8);
458 struct sigcontext __user *sc = &frame->sc;
459 int sig_size = (_NSIG_WORDS - 1) * sizeof(unsigned long);
461 if (copy_from_user(&set.sig[0], &sc->oldmask, sizeof(set.sig[0])) ||
462 copy_from_user(&set.sig[1], frame->extramask, sig_size))
465 set_current_blocked(&set);
467 if (copy_sc_from_user(¤t->thread.regs, sc))
470 /* Avoid ERESTART handling */
471 PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1;
472 return PT_REGS_SYSCALL_RET(¤t->thread.regs);
483 char __user *pretcode;
486 struct _xstate fpstate;
489 int setup_signal_stack_si(unsigned long stack_top, struct ksignal *ksig,
490 struct pt_regs *regs, sigset_t *set)
492 struct rt_sigframe __user *frame;
493 int err = 0, sig = ksig->sig;
496 frame = (struct rt_sigframe __user *)
497 round_down(stack_top - sizeof(struct rt_sigframe), 16);
498 /* Subtract 128 for a red zone and 8 for proper alignment */
499 frame = (struct rt_sigframe __user *) ((unsigned long) frame - 128 - 8);
501 if (!access_ok(frame, sizeof(*frame)))
504 if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
505 err |= copy_siginfo_to_user(&frame->info, &ksig->info);
510 /* Create the ucontext. */
511 err |= __put_user(0, &frame->uc.uc_flags);
512 err |= __put_user(0, &frame->uc.uc_link);
513 err |= __save_altstack(&frame->uc.uc_stack, PT_REGS_SP(regs));
514 err |= copy_sc_to_user(&frame->uc.uc_mcontext, &frame->fpstate, regs,
517 fp_to = (unsigned long)&frame->fpstate;
519 err |= __put_user(fp_to, &frame->uc.uc_mcontext.fpstate);
520 if (sizeof(*set) == 16) {
521 err |= __put_user(set->sig[0], &frame->uc.uc_sigmask.sig[0]);
522 err |= __put_user(set->sig[1], &frame->uc.uc_sigmask.sig[1]);
525 err |= __copy_to_user(&frame->uc.uc_sigmask, set,
529 * Set up to return from userspace. If provided, use a stub
530 * already in userspace.
532 /* x86-64 should always use SA_RESTORER. */
533 if (ksig->ka.sa.sa_flags & SA_RESTORER)
534 err |= __put_user((void *)ksig->ka.sa.sa_restorer,
537 /* could use a vstub here */
543 PT_REGS_SP(regs) = (unsigned long) frame;
544 PT_REGS_DI(regs) = sig;
545 /* In case the signal handler was declared without prototypes */
546 PT_REGS_AX(regs) = 0;
549 * This also works for non SA_SIGINFO handlers because they expect the
550 * next argument after the signal number on the stack.
552 PT_REGS_SI(regs) = (unsigned long) &frame->info;
553 PT_REGS_DX(regs) = (unsigned long) &frame->uc;
554 PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
560 SYSCALL_DEFINE0(rt_sigreturn)
562 unsigned long sp = PT_REGS_SP(¤t->thread.regs);
563 struct rt_sigframe __user *frame =
564 (struct rt_sigframe __user *)(sp - sizeof(long));
565 struct ucontext __user *uc = &frame->uc;
568 if (copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
571 set_current_blocked(&set);
573 if (copy_sc_from_user(¤t->thread.regs, &uc->uc_mcontext))
576 /* Avoid ERESTART handling */
577 PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1;
578 return PT_REGS_SYSCALL_RET(¤t->thread.regs);