2 * Copyright (C) 2004 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3 * Licensed under the GPL
6 #include <linux/ptrace.h>
7 #include <asm/unistd.h>
8 #include <asm/uaccess.h>
9 #include <asm/ucontext.h>
10 #include "frame_kern.h"
14 * FPU tag word conversions.
17 static inline unsigned short twd_i387_to_fxsr(unsigned short twd)
19 unsigned int tmp; /* to avoid 16 bit prefixes in the code */
21 /* Transform each pair of bits into 01 (valid) or 00 (empty) */
23 tmp = (tmp | (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */
24 /* and move the valid bits to the lower byte. */
25 tmp = (tmp | (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */
26 tmp = (tmp | (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */
27 tmp = (tmp | (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */
31 static inline unsigned long twd_fxsr_to_i387(struct user_fxsr_struct *fxsave)
33 struct _fpxreg *st = NULL;
34 unsigned long twd = (unsigned long) fxsave->twd;
36 unsigned long ret = 0xffff0000;
39 #define FPREG_ADDR(f, n) ((char *)&(f)->st_space + (n) * 16)
41 for (i = 0; i < 8; i++) {
43 st = (struct _fpxreg *) FPREG_ADDR(fxsave, i);
45 switch (st->exponent & 0x7fff) {
47 tag = 2; /* Special */
50 if ( !st->significand[0] &&
51 !st->significand[1] &&
52 !st->significand[2] &&
53 !st->significand[3] ) {
56 tag = 2; /* Special */
60 if (st->significand[3] & 0x8000) {
63 tag = 2; /* Special */
70 ret |= (tag << (2 * i));
76 static int convert_fxsr_to_user(struct _fpstate __user *buf,
77 struct user_fxsr_struct *fxsave)
80 struct _fpreg __user *to;
84 env[0] = (unsigned long)fxsave->cwd | 0xffff0000ul;
85 env[1] = (unsigned long)fxsave->swd | 0xffff0000ul;
86 env[2] = twd_fxsr_to_i387(fxsave);
88 env[4] = fxsave->fcs | ((unsigned long)fxsave->fop << 16);
92 if (__copy_to_user(buf, env, 7 * sizeof(unsigned long)))
96 from = (struct _fpxreg *) &fxsave->st_space[0];
97 for (i = 0; i < 8; i++, to++, from++) {
98 unsigned long __user *t = (unsigned long __user *)to;
99 unsigned long *f = (unsigned long *)from;
101 if (__put_user(*f, t) ||
102 __put_user(*(f + 1), t + 1) ||
103 __put_user(from->exponent, &to->exponent))
109 static int convert_fxsr_from_user(struct user_fxsr_struct *fxsave,
110 struct _fpstate __user *buf)
112 unsigned long env[7];
114 struct _fpreg __user *from;
117 if (copy_from_user( env, buf, 7 * sizeof(long)))
120 fxsave->cwd = (unsigned short)(env[0] & 0xffff);
121 fxsave->swd = (unsigned short)(env[1] & 0xffff);
122 fxsave->twd = twd_i387_to_fxsr((unsigned short)(env[2] & 0xffff));
123 fxsave->fip = env[3];
124 fxsave->fop = (unsigned short)((env[4] & 0xffff0000ul) >> 16);
125 fxsave->fcs = (env[4] & 0xffff);
126 fxsave->foo = env[5];
127 fxsave->fos = env[6];
129 to = (struct _fpxreg *) &fxsave->st_space[0];
131 for (i = 0; i < 8; i++, to++, from++) {
132 unsigned long *t = (unsigned long *)to;
133 unsigned long __user *f = (unsigned long __user *)from;
135 if (__get_user(*t, f) ||
136 __get_user(*(t + 1), f + 1) ||
137 __get_user(to->exponent, &from->exponent))
143 extern int have_fpx_regs;
145 static int copy_sc_from_user(struct pt_regs *regs,
146 struct sigcontext __user *from)
148 struct sigcontext sc;
151 err = copy_from_user(&sc, from, sizeof(sc));
155 pid = userspace_pid[current_thread_info()->cpu];
157 #define GETREG(regno, regname) regs->regs.gp[HOST_##regno] = sc.regname
173 GETREG(EFLAGS, flags);
178 struct user_fxsr_struct fpx;
180 err = copy_from_user(&fpx,
181 &((struct _fpstate __user *)sc.fpstate)->_fxsr_env[0],
182 sizeof(struct user_fxsr_struct));
186 err = convert_fxsr_from_user(&fpx, sc.fpstate);
190 err = restore_fpx_registers(pid, (unsigned long *) &fpx);
192 printk(KERN_ERR "copy_sc_from_user - "
193 "restore_fpx_registers failed, errno = %d\n",
198 struct user_i387_struct fp;
200 err = copy_from_user(&fp, sc.fpstate,
201 sizeof(struct user_i387_struct));
205 err = restore_fp_registers(pid, (unsigned long *) &fp);
207 printk(KERN_ERR "copy_sc_from_user - "
208 "restore_fp_registers failed, errno = %d\n",
217 static int copy_sc_to_user(struct sigcontext __user *to,
218 struct _fpstate __user *to_fp, struct pt_regs *regs,
221 struct sigcontext sc;
222 struct faultinfo * fi = ¤t->thread.arch.faultinfo;
224 memset(&sc, 0, sizeof(struct sigcontext));
226 sc.gs = REGS_GS(regs->regs.gp);
227 sc.fs = REGS_FS(regs->regs.gp);
228 sc.es = REGS_ES(regs->regs.gp);
229 sc.ds = REGS_DS(regs->regs.gp);
230 sc.di = REGS_EDI(regs->regs.gp);
231 sc.si = REGS_ESI(regs->regs.gp);
232 sc.bp = REGS_EBP(regs->regs.gp);
234 sc.bx = REGS_EBX(regs->regs.gp);
235 sc.dx = REGS_EDX(regs->regs.gp);
236 sc.cx = REGS_ECX(regs->regs.gp);
237 sc.ax = REGS_EAX(regs->regs.gp);
238 sc.ip = REGS_IP(regs->regs.gp);
239 sc.cs = REGS_CS(regs->regs.gp);
240 sc.flags = REGS_EFLAGS(regs->regs.gp);
241 sc.sp_at_signal = regs->regs.gp[UESP];
242 sc.ss = regs->regs.gp[SS];
244 sc.err = fi->error_code;
245 sc.trapno = fi->trap_no;
247 to_fp = (to_fp ? to_fp : (struct _fpstate __user *) (to + 1));
250 pid = userspace_pid[current_thread_info()->cpu];
252 struct user_fxsr_struct fpx;
254 err = save_fpx_registers(pid, (unsigned long *) &fpx);
256 printk(KERN_ERR "copy_sc_to_user - save_fpx_registers "
257 "failed, errno = %d\n", err);
261 err = convert_fxsr_to_user(to_fp, &fpx);
265 err |= __put_user(fpx.swd, &to_fp->status);
266 err |= __put_user(X86_FXSR_MAGIC, &to_fp->magic);
270 if (copy_to_user(&to_fp->_fxsr_env[0], &fpx,
271 sizeof(struct user_fxsr_struct)))
275 struct user_i387_struct fp;
277 err = save_fp_registers(pid, (unsigned long *) &fp);
278 if (copy_to_user(to_fp, &fp, sizeof(struct user_i387_struct)))
282 return copy_to_user(to, &sc, sizeof(sc));
285 static int copy_ucontext_to_user(struct ucontext __user *uc,
286 struct _fpstate __user *fp, sigset_t *set,
291 err |= put_user(current->sas_ss_sp, &uc->uc_stack.ss_sp);
292 err |= put_user(sas_ss_flags(sp), &uc->uc_stack.ss_flags);
293 err |= put_user(current->sas_ss_size, &uc->uc_stack.ss_size);
294 err |= copy_sc_to_user(&uc->uc_mcontext, fp, ¤t->thread.regs, sp);
295 err |= copy_to_user(&uc->uc_sigmask, set, sizeof(*set));
301 char __user *pretcode;
303 struct sigcontext sc;
304 struct _fpstate fpstate;
305 unsigned long extramask[_NSIG_WORDS-1];
311 char __user *pretcode;
313 struct siginfo __user *pinfo;
317 struct _fpstate fpstate;
321 int setup_signal_stack_sc(unsigned long stack_top, int sig,
322 struct k_sigaction *ka, struct pt_regs *regs,
325 struct sigframe __user *frame;
326 void __user *restorer;
327 unsigned long save_sp = PT_REGS_SP(regs);
330 /* This is the same calculation as i386 - ((sp + 4) & 15) == 0 */
331 stack_top = ((stack_top + 4) & -16UL) - 4;
332 frame = (struct sigframe __user *) stack_top - 1;
333 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
336 restorer = frame->retcode;
337 if (ka->sa.sa_flags & SA_RESTORER)
338 restorer = ka->sa.sa_restorer;
340 /* Update SP now because the page fault handler refuses to extend
341 * the stack if the faulting address is too far below the current
342 * SP, which frame now certainly is. If there's an error, the original
343 * value is restored on the way out.
344 * When writing the sigcontext to the stack, we have to write the
345 * original value, so that's passed to copy_sc_to_user, which does
346 * the right thing with it.
348 PT_REGS_SP(regs) = (unsigned long) frame;
350 err |= __put_user(restorer, &frame->pretcode);
351 err |= __put_user(sig, &frame->sig);
352 err |= copy_sc_to_user(&frame->sc, NULL, regs, save_sp);
353 err |= __put_user(mask->sig[0], &frame->sc.oldmask);
355 err |= __copy_to_user(&frame->extramask, &mask->sig[1],
356 sizeof(frame->extramask));
359 * This is popl %eax ; movl $,%eax ; int $0x80
361 * WE DO NOT USE IT ANY MORE! It's only left here for historical
362 * reasons and because gdb uses it as a signature to notice
363 * signal handler stack frames.
365 err |= __put_user(0xb858, (short __user *)(frame->retcode+0));
366 err |= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2));
367 err |= __put_user(0x80cd, (short __user *)(frame->retcode+6));
372 PT_REGS_SP(regs) = (unsigned long) frame;
373 PT_REGS_IP(regs) = (unsigned long) ka->sa.sa_handler;
374 PT_REGS_EAX(regs) = (unsigned long) sig;
375 PT_REGS_EDX(regs) = (unsigned long) 0;
376 PT_REGS_ECX(regs) = (unsigned long) 0;
378 if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED))
379 ptrace_notify(SIGTRAP);
383 PT_REGS_SP(regs) = save_sp;
387 int setup_signal_stack_si(unsigned long stack_top, int sig,
388 struct k_sigaction *ka, struct pt_regs *regs,
389 siginfo_t *info, sigset_t *mask)
391 struct rt_sigframe __user *frame;
392 void __user *restorer;
393 unsigned long save_sp = PT_REGS_SP(regs);
397 frame = (struct rt_sigframe __user *) stack_top - 1;
398 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
401 restorer = frame->retcode;
402 if (ka->sa.sa_flags & SA_RESTORER)
403 restorer = ka->sa.sa_restorer;
405 /* See comment above about why this is here */
406 PT_REGS_SP(regs) = (unsigned long) frame;
408 err |= __put_user(restorer, &frame->pretcode);
409 err |= __put_user(sig, &frame->sig);
410 err |= __put_user(&frame->info, &frame->pinfo);
411 err |= __put_user(&frame->uc, &frame->puc);
412 err |= copy_siginfo_to_user(&frame->info, info);
413 err |= copy_ucontext_to_user(&frame->uc, &frame->fpstate, mask,
417 * This is movl $,%eax ; int $0x80
419 * WE DO NOT USE IT ANY MORE! It's only left here for historical
420 * reasons and because gdb uses it as a signature to notice
421 * signal handler stack frames.
423 err |= __put_user(0xb8, (char __user *)(frame->retcode+0));
424 err |= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1));
425 err |= __put_user(0x80cd, (short __user *)(frame->retcode+5));
430 PT_REGS_IP(regs) = (unsigned long) ka->sa.sa_handler;
431 PT_REGS_EAX(regs) = (unsigned long) sig;
432 PT_REGS_EDX(regs) = (unsigned long) &frame->info;
433 PT_REGS_ECX(regs) = (unsigned long) &frame->uc;
435 if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED))
436 ptrace_notify(SIGTRAP);
440 PT_REGS_SP(regs) = save_sp;
444 long sys_sigreturn(struct pt_regs regs)
446 unsigned long sp = PT_REGS_SP(¤t->thread.regs);
447 struct sigframe __user *frame = (struct sigframe __user *)(sp - 8);
449 struct sigcontext __user *sc = &frame->sc;
450 unsigned long __user *oldmask = &sc->oldmask;
451 unsigned long __user *extramask = frame->extramask;
452 int sig_size = (_NSIG_WORDS - 1) * sizeof(unsigned long);
454 if (copy_from_user(&set.sig[0], oldmask, sizeof(set.sig[0])) ||
455 copy_from_user(&set.sig[1], extramask, sig_size))
458 sigdelsetmask(&set, ~_BLOCKABLE);
459 set_current_blocked(&set);
461 if (copy_sc_from_user(¤t->thread.regs, sc))
464 /* Avoid ERESTART handling */
465 PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1;
466 return PT_REGS_SYSCALL_RET(¤t->thread.regs);
469 force_sig(SIGSEGV, current);
473 long sys_rt_sigreturn(struct pt_regs regs)
475 unsigned long sp = PT_REGS_SP(¤t->thread.regs);
476 struct rt_sigframe __user *frame =
477 (struct rt_sigframe __user *) (sp - 4);
479 struct ucontext __user *uc = &frame->uc;
480 int sig_size = _NSIG_WORDS * sizeof(unsigned long);
482 if (copy_from_user(&set, &uc->uc_sigmask, sig_size))
485 sigdelsetmask(&set, ~_BLOCKABLE);
486 set_current_blocked(&set);
488 if (copy_sc_from_user(¤t->thread.regs, &uc->uc_mcontext))
491 /* Avoid ERESTART handling */
492 PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1;
493 return PT_REGS_SYSCALL_RET(¤t->thread.regs);
496 force_sig(SIGSEGV, current);