/* * linux/arch/m68k/kernel/signal.c * * Copyright (C) 1991, 1992 Linus Torvalds * * This file is subject to the terms and conditions of the GNU General Public * License. See the file COPYING in the main directory of this archive * for more details. */ /* * Linux/m68k support by Hamish Macdonald * * 68060 fixes by Jesper Skov * * 1997-12-01 Modified for POSIX.1b signals by Andreas Schwab * * mathemu support by Roman Zippel * (Note: fpstate in the signal context is completely ignored for the emulator * and the internal floating point format is put on stack) */ /* * ++roman (07/09/96): implemented signal stacks (specially for tosemu on * Atari :-) Current limitation: Only one sigstack can be active at one time. * If a second signal with SA_ONSTACK set arrives while working on a sigstack, * SA_ONSTACK is ignored. This behaviour avoids lots of trouble with nested * signal handlers! */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef CONFIG_MMU /* * Handle the slight differences in classic 68k and ColdFire trap frames. */ #ifdef CONFIG_COLDFIRE #define FORMAT 4 #define FMT4SIZE 0 #else #define FORMAT 0 #define FMT4SIZE sizeof_field(struct frame, un.fmt4) #endif static const int frame_size_change[16] = { [1] = -1, /* sizeof_field(struct frame, un.fmt1), */ [2] = sizeof_field(struct frame, un.fmt2), [3] = sizeof_field(struct frame, un.fmt3), [4] = FMT4SIZE, [5] = -1, /* sizeof_field(struct frame, un.fmt5), */ [6] = -1, /* sizeof_field(struct frame, un.fmt6), */ [7] = sizeof_field(struct frame, un.fmt7), [8] = -1, /* sizeof_field(struct frame, un.fmt8), */ [9] = sizeof_field(struct frame, un.fmt9), [10] = sizeof_field(struct frame, un.fmta), [11] = sizeof_field(struct frame, un.fmtb), [12] = -1, /* sizeof_field(struct frame, un.fmtc), */ [13] = -1, /* sizeof_field(struct frame, un.fmtd), */ [14] = -1, /* sizeof_field(struct frame, un.fmte), */ [15] = -1, /* sizeof_field(struct frame, un.fmtf), */ }; static inline int frame_extra_sizes(int f) { return frame_size_change[f]; } int fixup_exception(struct pt_regs *regs) { const struct exception_table_entry *fixup; struct pt_regs *tregs; /* Are we prepared to handle this kernel fault? */ fixup = search_exception_tables(regs->pc); if (!fixup) return 0; /* Create a new four word stack frame, discarding the old one. */ regs->stkadj = frame_extra_sizes(regs->format); tregs = (struct pt_regs *)((long)regs + regs->stkadj); tregs->vector = regs->vector; tregs->format = FORMAT; tregs->pc = fixup->fixup; tregs->sr = regs->sr; return 1; } static inline void push_cache (unsigned long vaddr) { /* * Using the old cache_push_v() was really a big waste. * * What we are trying to do is to flush 8 bytes to ram. * Flushing 2 cache lines of 16 bytes is much cheaper than * flushing 1 or 2 pages, as previously done in * cache_push_v(). * Jes */ if (CPU_IS_040) { unsigned long temp; __asm__ __volatile__ (".chip 68040\n\t" "nop\n\t" "ptestr (%1)\n\t" "movec %%mmusr,%0\n\t" ".chip 68k" : "=r" (temp) : "a" (vaddr)); temp &= PAGE_MASK; temp |= vaddr & ~PAGE_MASK; __asm__ __volatile__ (".chip 68040\n\t" "nop\n\t" "cpushl %%bc,(%0)\n\t" ".chip 68k" : : "a" (temp)); } else if (CPU_IS_060) { unsigned long temp; __asm__ __volatile__ (".chip 68060\n\t" "plpar (%0)\n\t" ".chip 68k" : "=a" (temp) : "0" (vaddr)); __asm__ __volatile__ (".chip 68060\n\t" "cpushl %%bc,(%0)\n\t" ".chip 68k" : : "a" (temp)); } else if (!CPU_IS_COLDFIRE) { /* * 68030/68020 have no writeback cache; * still need to clear icache. * Note that vaddr is guaranteed to be long word aligned. */ unsigned long temp; asm volatile ("movec %%cacr,%0" : "=r" (temp)); temp += 4; asm volatile ("movec %0,%%caar\n\t" "movec %1,%%cacr" : : "r" (vaddr), "r" (temp)); asm volatile ("movec %0,%%caar\n\t" "movec %1,%%cacr" : : "r" (vaddr + 4), "r" (temp)); } else { /* CPU_IS_COLDFIRE */ #if defined(CONFIG_CACHE_COPYBACK) flush_cf_dcache(0, DCACHE_MAX_ADDR); #endif /* Invalidate instruction cache for the pushed bytes */ clear_cf_icache(vaddr, vaddr + 8); } } static inline void adjustformat(struct pt_regs *regs) { } static inline void save_a5_state(struct sigcontext *sc, struct pt_regs *regs) { } #else /* CONFIG_MMU */ void ret_from_user_signal(void); void ret_from_user_rt_signal(void); static inline int frame_extra_sizes(int f) { /* No frame size adjustments required on non-MMU CPUs */ return 0; } static inline void adjustformat(struct pt_regs *regs) { /* * set format byte to make stack appear modulo 4, which it will * be when doing the rte */ regs->format = 0x4; } static inline void save_a5_state(struct sigcontext *sc, struct pt_regs *regs) { sc->sc_a5 = ((struct switch_stack *)regs - 1)->a5; } static inline void push_cache(unsigned long vaddr) { } #endif /* CONFIG_MMU */ /* * Do a signal return; undo the signal stack. * * Keep the return code on the stack quadword aligned! * That makes the cache flush below easier. */ struct sigframe { char __user *pretcode; int sig; int code; struct sigcontext __user *psc; char retcode[8]; unsigned long extramask[_NSIG_WORDS-1]; struct sigcontext sc; }; struct rt_sigframe { char __user *pretcode; int sig; struct siginfo __user *pinfo; void __user *puc; char retcode[8]; struct siginfo info; struct ucontext uc; }; #define FPCONTEXT_SIZE 216 #define uc_fpstate uc_filler[0] #define uc_formatvec uc_filler[FPCONTEXT_SIZE/4] #define uc_extra uc_filler[FPCONTEXT_SIZE/4+1] #ifdef CONFIG_FPU static unsigned char fpu_version; /* version number of fpu, set by setup_frame */ static inline int restore_fpu_state(struct sigcontext *sc) { int err = 1; if (FPU_IS_EMU) { /* restore registers */ memcpy(current->thread.fpcntl, sc->sc_fpcntl, 12); memcpy(current->thread.fp, sc->sc_fpregs, 24); return 0; } if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) { /* Verify the frame format. */ if (!(CPU_IS_060 || CPU_IS_COLDFIRE) && (sc->sc_fpstate[0] != fpu_version)) goto out; if (CPU_IS_020_OR_030) { if (m68k_fputype & FPU_68881 && !(sc->sc_fpstate[1] == 0x18 || sc->sc_fpstate[1] == 0xb4)) goto out; if (m68k_fputype & FPU_68882 && !(sc->sc_fpstate[1] == 0x38 || sc->sc_fpstate[1] == 0xd4)) goto out; } else if (CPU_IS_040) { if (!(sc->sc_fpstate[1] == 0x00 || sc->sc_fpstate[1] == 0x28 || sc->sc_fpstate[1] == 0x60)) goto out; } else if (CPU_IS_060) { if (!(sc->sc_fpstate[3] == 0x00 || sc->sc_fpstate[3] == 0x60 || sc->sc_fpstate[3] == 0xe0)) goto out; } else if (CPU_IS_COLDFIRE) { if (!(sc->sc_fpstate[0] == 0x00 || sc->sc_fpstate[0] == 0x05 || sc->sc_fpstate[0] == 0xe5)) goto out; } else goto out; if (CPU_IS_COLDFIRE) { __asm__ volatile ("fmovemd %0,%%fp0-%%fp1\n\t" "fmovel %1,%%fpcr\n\t" "fmovel %2,%%fpsr\n\t" "fmovel %3,%%fpiar" : /* no outputs */ : "m" (sc->sc_fpregs[0]), "m" (sc->sc_fpcntl[0]), "m" (sc->sc_fpcntl[1]), "m" (sc->sc_fpcntl[2])); } else { __asm__ volatile (".chip 68k/68881\n\t" "fmovemx %0,%%fp0-%%fp1\n\t" "fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t" ".chip 68k" : /* no outputs */ : "m" (*sc->sc_fpregs), "m" (*sc->sc_fpcntl)); } } if (CPU_IS_COLDFIRE) { __asm__ volatile ("frestore %0" : : "m" (*sc->sc_fpstate)); } else { __asm__ volatile (".chip 68k/68881\n\t" "frestore %0\n\t" ".chip 68k" : : "m" (*sc->sc_fpstate)); } err = 0; out: return err; } static inline int rt_restore_fpu_state(struct ucontext __user *uc) { unsigned char fpstate[FPCONTEXT_SIZE]; int context_size = CPU_IS_060 ? 8 : (CPU_IS_COLDFIRE ? 12 : 0); fpregset_t fpregs; int err = 1; if (FPU_IS_EMU) { /* restore fpu control register */ if (__copy_from_user(current->thread.fpcntl, uc->uc_mcontext.fpregs.f_fpcntl, 12)) goto out; /* restore all other fpu register */ if (__copy_from_user(current->thread.fp, uc->uc_mcontext.fpregs.f_fpregs, 96)) goto out; return 0; } if (__get_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate)) goto out; if (CPU_IS_060 ? fpstate[2] : fpstate[0]) { if (!(CPU_IS_060 || CPU_IS_COLDFIRE)) context_size = fpstate[1]; /* Verify the frame format. */ if (!(CPU_IS_060 || CPU_IS_COLDFIRE) && (fpstate[0] != fpu_version)) goto out; if (CPU_IS_020_OR_030) { if (m68k_fputype & FPU_68881 && !(context_size == 0x18 || context_size == 0xb4)) goto out; if (m68k_fputype & FPU_68882 && !(context_size == 0x38 || context_size == 0xd4)) goto out; } else if (CPU_IS_040) { if (!(context_size == 0x00 || context_size == 0x28 || context_size == 0x60)) goto out; } else if (CPU_IS_060) { if (!(fpstate[3] == 0x00 || fpstate[3] == 0x60 || fpstate[3] == 0xe0)) goto out; } else if (CPU_IS_COLDFIRE) { if (!(fpstate[3] == 0x00 || fpstate[3] == 0x05 || fpstate[3] == 0xe5)) goto out; } else goto out; if (__copy_from_user(&fpregs, &uc->uc_mcontext.fpregs, sizeof(fpregs))) goto out; if (CPU_IS_COLDFIRE) { __asm__ volatile ("fmovemd %0,%%fp0-%%fp7\n\t" "fmovel %1,%%fpcr\n\t" "fmovel %2,%%fpsr\n\t" "fmovel %3,%%fpiar" : /* no outputs */ : "m" (fpregs.f_fpregs[0]), "m" (fpregs.f_fpcntl[0]), "m" (fpregs.f_fpcntl[1]), "m" (fpregs.f_fpcntl[2])); } else { __asm__ volatile (".chip 68k/68881\n\t" "fmovemx %0,%%fp0-%%fp7\n\t" "fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t" ".chip 68k" : /* no outputs */ : "m" (*fpregs.f_fpregs), "m" (*fpregs.f_fpcntl)); } } if (context_size && __copy_from_user(fpstate + 4, (long __user *)&uc->uc_fpstate + 1, context_size)) goto out; if (CPU_IS_COLDFIRE) { __asm__ volatile ("frestore %0" : : "m" (*fpstate)); } else { __asm__ volatile (".chip 68k/68881\n\t" "frestore %0\n\t" ".chip 68k" : : "m" (*fpstate)); } err = 0; out: return err; } /* * Set up a signal frame. */ static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs) { if (FPU_IS_EMU) { /* save registers */ memcpy(sc->sc_fpcntl, current->thread.fpcntl, 12); memcpy(sc->sc_fpregs, current->thread.fp, 24); return; } if (CPU_IS_COLDFIRE) { __asm__ volatile ("fsave %0" : : "m" (*sc->sc_fpstate) : "memory"); } else { __asm__ volatile (".chip 68k/68881\n\t" "fsave %0\n\t" ".chip 68k" : : "m" (*sc->sc_fpstate) : "memory"); } if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) { fpu_version = sc->sc_fpstate[0]; if (CPU_IS_020_OR_030 && !regs->stkadj && regs->vector >= (VEC_FPBRUC * 4) && regs->vector <= (VEC_FPNAN * 4)) { /* Clear pending exception in 68882 idle frame */ if (*(unsigned short *) sc->sc_fpstate == 0x1f38) sc->sc_fpstate[0x38] |= 1 << 3; } if (CPU_IS_COLDFIRE) { __asm__ volatile ("fmovemd %%fp0-%%fp1,%0\n\t" "fmovel %%fpcr,%1\n\t" "fmovel %%fpsr,%2\n\t" "fmovel %%fpiar,%3" : "=m" (sc->sc_fpregs[0]), "=m" (sc->sc_fpcntl[0]), "=m" (sc->sc_fpcntl[1]), "=m" (sc->sc_fpcntl[2]) : /* no inputs */ : "memory"); } else { __asm__ volatile (".chip 68k/68881\n\t" "fmovemx %%fp0-%%fp1,%0\n\t" "fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t" ".chip 68k" : "=m" (*sc->sc_fpregs), "=m" (*sc->sc_fpcntl) : /* no inputs */ : "memory"); } } } static inline int rt_save_fpu_state(struct ucontext __user *uc, struct pt_regs *regs) { unsigned char fpstate[FPCONTEXT_SIZE]; int context_size = CPU_IS_060 ? 8 : (CPU_IS_COLDFIRE ? 12 : 0); int err = 0; if (FPU_IS_EMU) { /* save fpu control register */ err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpcntl, current->thread.fpcntl, 12); /* save all other fpu register */ err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpregs, current->thread.fp, 96); return err; } if (CPU_IS_COLDFIRE) { __asm__ volatile ("fsave %0" : : "m" (*fpstate) : "memory"); } else { __asm__ volatile (".chip 68k/68881\n\t" "fsave %0\n\t" ".chip 68k" : : "m" (*fpstate) : "memory"); } err |= __put_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate); if (CPU_IS_060 ? fpstate[2] : fpstate[0]) { fpregset_t fpregs; if (!(CPU_IS_060 || CPU_IS_COLDFIRE)) context_size = fpstate[1]; fpu_version = fpstate[0]; if (CPU_IS_020_OR_030 && !regs->stkadj && regs->vector >= (VEC_FPBRUC * 4) && regs->vector <= (VEC_FPNAN * 4)) { /* Clear pending exception in 68882 idle frame */ if (*(unsigned short *) fpstate == 0x1f38) fpstate[0x38] |= 1 << 3; } if (CPU_IS_COLDFIRE) { __asm__ volatile ("fmovemd %%fp0-%%fp7,%0\n\t" "fmovel %%fpcr,%1\n\t" "fmovel %%fpsr,%2\n\t" "fmovel %%fpiar,%3" : "=m" (fpregs.f_fpregs[0]), "=m" (fpregs.f_fpcntl[0]), "=m" (fpregs.f_fpcntl[1]), "=m" (fpregs.f_fpcntl[2]) : /* no inputs */ : "memory"); } else { __asm__ volatile (".chip 68k/68881\n\t" "fmovemx %%fp0-%%fp7,%0\n\t" "fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t" ".chip 68k" : "=m" (*fpregs.f_fpregs), "=m" (*fpregs.f_fpcntl) : /* no inputs */ : "memory"); } err |= copy_to_user(&uc->uc_mcontext.fpregs, &fpregs, sizeof(fpregs)); } if (context_size) err |= copy_to_user((long __user *)&uc->uc_fpstate + 1, fpstate + 4, context_size); return err; } #else /* CONFIG_FPU */ /* * For the case with no FPU configured these all do nothing. */ static inline int restore_fpu_state(struct sigcontext *sc) { return 0; } static inline int rt_restore_fpu_state(struct ucontext __user *uc) { return 0; } static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs) { } static inline int rt_save_fpu_state(struct ucontext __user *uc, struct pt_regs *regs) { return 0; } #endif /* CONFIG_FPU */ static inline void siginfo_build_tests(void) { /* * This needs to be tested on m68k as it has a lesser * alignment requirement than x86 and that can cause surprises. */ /* This is part of the ABI and can never change in size: */ BUILD_BUG_ON(sizeof(siginfo_t) != 128); /* Ensure the known fields never change in location */ BUILD_BUG_ON(offsetof(siginfo_t, si_signo) != 0); BUILD_BUG_ON(offsetof(siginfo_t, si_errno) != 4); BUILD_BUG_ON(offsetof(siginfo_t, si_code) != 8); /* _kill */ BUILD_BUG_ON(offsetof(siginfo_t, si_pid) != 0x0c); BUILD_BUG_ON(offsetof(siginfo_t, si_uid) != 0x10); /* _timer */ BUILD_BUG_ON(offsetof(siginfo_t, si_tid) != 0x0c); BUILD_BUG_ON(offsetof(siginfo_t, si_overrun) != 0x10); BUILD_BUG_ON(offsetof(siginfo_t, si_value) != 0x14); /* _rt */ BUILD_BUG_ON(offsetof(siginfo_t, si_pid) != 0x0c); BUILD_BUG_ON(offsetof(siginfo_t, si_uid) != 0x10); BUILD_BUG_ON(offsetof(siginfo_t, si_value) != 0x14); /* _sigchld */ BUILD_BUG_ON(offsetof(siginfo_t, si_pid) != 0x0c); BUILD_BUG_ON(offsetof(siginfo_t, si_uid) != 0x10); BUILD_BUG_ON(offsetof(siginfo_t, si_status) != 0x14); BUILD_BUG_ON(offsetof(siginfo_t, si_utime) != 0x18); BUILD_BUG_ON(offsetof(siginfo_t, si_stime) != 0x1c); /* _sigfault */ BUILD_BUG_ON(offsetof(siginfo_t, si_addr) != 0x0c); /* _sigfault._mcerr */ BUILD_BUG_ON(offsetof(siginfo_t, si_addr_lsb) != 0x10); /* _sigfault._addr_bnd */ BUILD_BUG_ON(offsetof(siginfo_t, si_lower) != 0x12); BUILD_BUG_ON(offsetof(siginfo_t, si_upper) != 0x16); /* _sigfault._addr_pkey */ BUILD_BUG_ON(offsetof(siginfo_t, si_pkey) != 0x12); /* _sigfault._perf */ BUILD_BUG_ON(offsetof(siginfo_t, si_perf_data) != 0x10); BUILD_BUG_ON(offsetof(siginfo_t, si_perf_type) != 0x14); BUILD_BUG_ON(offsetof(siginfo_t, si_perf_flags) != 0x18); /* _sigpoll */ BUILD_BUG_ON(offsetof(siginfo_t, si_band) != 0x0c); BUILD_BUG_ON(offsetof(siginfo_t, si_fd) != 0x10); /* _sigsys */ BUILD_BUG_ON(offsetof(siginfo_t, si_call_addr) != 0x0c); BUILD_BUG_ON(offsetof(siginfo_t, si_syscall) != 0x10); BUILD_BUG_ON(offsetof(siginfo_t, si_arch) != 0x14); /* any new si_fields should be added here */ } static int mangle_kernel_stack(struct pt_regs *regs, int formatvec, void __user *fp) { int extra = frame_extra_sizes(formatvec >> 12); char buf[sizeof_field(struct frame, un)]; if (extra < 0) { /* * user process trying to return with weird frame format */ pr_debug("user process returning with weird frame format\n"); return -1; } if (extra && copy_from_user(buf, fp, extra)) return -1; regs->format = formatvec >> 12; regs->vector = formatvec & 0xfff; if (extra) { void *p = (struct switch_stack *)regs - 1; struct frame *new = (void *)regs - extra; int size = sizeof(struct pt_regs)+sizeof(struct switch_stack); memmove(p - extra, p, size); memcpy(p - extra + size, buf, extra); current->thread.esp0 = (unsigned long)&new->ptregs; #ifdef CONFIG_M68040 /* on 68040 complete pending writebacks if any */ if (new->ptregs.format == 7) // bus error frame berr_040cleanup(new); #endif } return extra; } static inline int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *usc, void __user *fp) { int formatvec; struct sigcontext context; siginfo_build_tests(); /* Always make any pending restarted system calls return -EINTR */ current->restart_block.fn = do_no_restart_syscall; /* get previous context */ if (copy_from_user(&context, usc, sizeof(context))) return -1; /* restore passed registers */ regs->d0 = context.sc_d0; regs->d1 = context.sc_d1; regs->a0 = context.sc_a0; regs->a1 = context.sc_a1; regs->sr = (regs->sr & 0xff00) | (context.sc_sr & 0xff); regs->pc = context.sc_pc; regs->orig_d0 = -1; /* disable syscall checks */ wrusp(context.sc_usp); formatvec = context.sc_formatvec; if (restore_fpu_state(&context)) return -1; return mangle_kernel_stack(regs, formatvec, fp); } static inline int rt_restore_ucontext(struct pt_regs *regs, struct switch_stack *sw, struct ucontext __user *uc) { int temp; greg_t __user *gregs = uc->uc_mcontext.gregs; unsigned long usp; int err; /* Always make any pending restarted system calls return -EINTR */ current->restart_block.fn = do_no_restart_syscall; err = __get_user(temp, &uc->uc_mcontext.version); if (temp != MCONTEXT_VERSION) return -1; /* restore passed registers */ err |= __get_user(regs->d0, &gregs[0]); err |= __get_user(regs->d1, &gregs[1]); err |= __get_user(regs->d2, &gregs[2]); err |= __get_user(regs->d3, &gregs[3]); err |= __get_user(regs->d4, &gregs[4]); err |= __get_user(regs->d5, &gregs[5]); err |= __get_user(sw->d6, &gregs[6]); err |= __get_user(sw->d7, &gregs[7]); err |= __get_user(regs->a0, &gregs[8]); err |= __get_user(regs->a1, &gregs[9]); err |= __get_user(regs->a2, &gregs[10]); err |= __get_user(sw->a3, &gregs[11]); err |= __get_user(sw->a4, &gregs[12]); err |= __get_user(sw->a5, &gregs[13]); err |= __get_user(sw->a6, &gregs[14]); err |= __get_user(usp, &gregs[15]); wrusp(usp); err |= __get_user(regs->pc, &gregs[16]); err |= __get_user(temp, &gregs[17]); regs->sr = (regs->sr & 0xff00) | (temp & 0xff); regs->orig_d0 = -1; /* disable syscall checks */ err |= __get_user(temp, &uc->uc_formatvec); err |= rt_restore_fpu_state(uc); err |= restore_altstack(&uc->uc_stack); if (err) return -1; return mangle_kernel_stack(regs, temp, &uc->uc_extra); } asmlinkage void *do_sigreturn(struct pt_regs *regs, struct switch_stack *sw) { unsigned long usp = rdusp(); struct sigframe __user *frame = (struct sigframe __user *)(usp - 4); sigset_t set; int size; if (!access_ok(frame, sizeof(*frame))) goto badframe; if (__get_user(set.sig[0], &frame->sc.sc_mask) || (_NSIG_WORDS > 1 && __copy_from_user(&set.sig[1], &frame->extramask, sizeof(frame->extramask)))) goto badframe; set_current_blocked(&set); size = restore_sigcontext(regs, &frame->sc, frame + 1); if (size < 0) goto badframe; return (void *)sw - size; badframe: force_sig(SIGSEGV); return sw; } asmlinkage void *do_rt_sigreturn(struct pt_regs *regs, struct switch_stack *sw) { unsigned long usp = rdusp(); struct rt_sigframe __user *frame = (struct rt_sigframe __user *)(usp - 4); sigset_t set; int size; if (!access_ok(frame, sizeof(*frame))) goto badframe; if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) goto badframe; set_current_blocked(&set); size = rt_restore_ucontext(regs, sw, &frame->uc); if (size < 0) goto badframe; return (void *)sw - size; badframe: force_sig(SIGSEGV); return sw; } static inline struct pt_regs *rte_regs(struct pt_regs *regs) { return (void *)regs + regs->stkadj; } static void setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs, unsigned long mask) { struct pt_regs *tregs = rte_regs(regs); sc->sc_mask = mask; sc->sc_usp = rdusp(); sc->sc_d0 = regs->d0; sc->sc_d1 = regs->d1; sc->sc_a0 = regs->a0; sc->sc_a1 = regs->a1; sc->sc_sr = tregs->sr; sc->sc_pc = tregs->pc; sc->sc_formatvec = tregs->format << 12 | tregs->vector; save_a5_state(sc, regs); save_fpu_state(sc, regs); } static inline int rt_setup_ucontext(struct ucontext __user *uc, struct pt_regs *regs) { struct switch_stack *sw = (struct switch_stack *)regs - 1; struct pt_regs *tregs = rte_regs(regs); greg_t __user *gregs = uc->uc_mcontext.gregs; int err = 0; err |= __put_user(MCONTEXT_VERSION, &uc->uc_mcontext.version); err |= __put_user(regs->d0, &gregs[0]); err |= __put_user(regs->d1, &gregs[1]); err |= __put_user(regs->d2, &gregs[2]); err |= __put_user(regs->d3, &gregs[3]); err |= __put_user(regs->d4, &gregs[4]); err |= __put_user(regs->d5, &gregs[5]); err |= __put_user(sw->d6, &gregs[6]); err |= __put_user(sw->d7, &gregs[7]); err |= __put_user(regs->a0, &gregs[8]); err |= __put_user(regs->a1, &gregs[9]); err |= __put_user(regs->a2, &gregs[10]); err |= __put_user(sw->a3, &gregs[11]); err |= __put_user(sw->a4, &gregs[12]); err |= __put_user(sw->a5, &gregs[13]); err |= __put_user(sw->a6, &gregs[14]); err |= __put_user(rdusp(), &gregs[15]); err |= __put_user(tregs->pc, &gregs[16]); err |= __put_user(tregs->sr, &gregs[17]); err |= __put_user((tregs->format << 12) | tregs->vector, &uc->uc_formatvec); err |= rt_save_fpu_state(uc, regs); return err; } static inline void __user * get_sigframe(struct ksignal *ksig, size_t frame_size) { unsigned long usp = sigsp(rdusp(), ksig); return (void __user *)((usp - frame_size) & -8UL); } static int setup_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs) { struct sigframe __user *frame; struct pt_regs *tregs = rte_regs(regs); int fsize = frame_extra_sizes(tregs->format); struct sigcontext context; int err = 0, sig = ksig->sig; if (fsize < 0) { pr_debug("setup_frame: Unknown frame format %#x\n", tregs->format); return -EFAULT; } frame = get_sigframe(ksig, sizeof(*frame) + fsize); if (fsize) err |= copy_to_user (frame + 1, regs + 1, fsize); err |= __put_user(sig, &frame->sig); err |= __put_user(tregs->vector, &frame->code); err |= __put_user(&frame->sc, &frame->psc); if (_NSIG_WORDS > 1) err |= copy_to_user(frame->extramask, &set->sig[1], sizeof(frame->extramask)); setup_sigcontext(&context, regs, set->sig[0]); err |= copy_to_user (&frame->sc, &context, sizeof(context)); /* Set up to return from userspace. */ #ifdef CONFIG_MMU err |= __put_user(frame->retcode, &frame->pretcode); /* moveq #,d0; trap #0 */ err |= __put_user(0x70004e40 + (__NR_sigreturn << 16), (long __user *)(frame->retcode)); #else err |= __put_user((long) ret_from_user_signal, (long __user *) &frame->pretcode); #endif if (err) return -EFAULT; push_cache ((unsigned long) &frame->retcode); /* * This is subtle; if we build more than one sigframe, all but the * first one will see frame format 0 and have fsize == 0, so we won't * screw stkadj. */ if (fsize) { regs->stkadj = fsize; tregs = rte_regs(regs); pr_debug("Performing stackadjust=%04lx\n", regs->stkadj); tregs->vector = 0; tregs->format = 0; tregs->sr = regs->sr; } /* * Set up registers for signal handler. All the state we are about * to destroy is successfully copied to sigframe. */ wrusp ((unsigned long) frame); tregs->pc = (unsigned long) ksig->ka.sa.sa_handler; adjustformat(regs); return 0; } static int setup_rt_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs) { struct rt_sigframe __user *frame; struct pt_regs *tregs = rte_regs(regs); int fsize = frame_extra_sizes(tregs->format); int err = 0, sig = ksig->sig; if (fsize < 0) { pr_debug("setup_frame: Unknown frame format %#x\n", regs->format); return -EFAULT; } frame = get_sigframe(ksig, sizeof(*frame)); if (fsize) err |= copy_to_user (&frame->uc.uc_extra, regs + 1, fsize); err |= __put_user(sig, &frame->sig); err |= __put_user(&frame->info, &frame->pinfo); err |= __put_user(&frame->uc, &frame->puc); err |= copy_siginfo_to_user(&frame->info, &ksig->info); /* Create the ucontext. */ err |= __put_user(0, &frame->uc.uc_flags); err |= __put_user(NULL, &frame->uc.uc_link); err |= __save_altstack(&frame->uc.uc_stack, rdusp()); err |= rt_setup_ucontext(&frame->uc, regs); err |= copy_to_user (&frame->uc.uc_sigmask, set, sizeof(*set)); /* Set up to return from userspace. */ #ifdef CONFIG_MMU err |= __put_user(frame->retcode, &frame->pretcode); #ifdef __mcoldfire__ /* movel #__NR_rt_sigreturn,d0; trap #0 */ err |= __put_user(0x203c0000, (long __user *)(frame->retcode + 0)); err |= __put_user(0x00004e40 + (__NR_rt_sigreturn << 16), (long __user *)(frame->retcode + 4)); #else /* moveq #,d0; notb d0; trap #0 */ err |= __put_user(0x70004600 + ((__NR_rt_sigreturn ^ 0xff) << 16), (long __user *)(frame->retcode + 0)); err |= __put_user(0x4e40, (short __user *)(frame->retcode + 4)); #endif #else err |= __put_user((long) ret_from_user_rt_signal, (long __user *) &frame->pretcode); #endif /* CONFIG_MMU */ if (err) return -EFAULT; push_cache ((unsigned long) &frame->retcode); /* * This is subtle; if we build more than one sigframe, all but the * first one will see frame format 0 and have fsize == 0, so we won't * screw stkadj. */ if (fsize) { regs->stkadj = fsize; tregs = rte_regs(regs); pr_debug("Performing stackadjust=%04lx\n", regs->stkadj); tregs->vector = 0; tregs->format = 0; tregs->sr = regs->sr; } /* * Set up registers for signal handler. All the state we are about * to destroy is successfully copied to sigframe. */ wrusp ((unsigned long) frame); tregs->pc = (unsigned long) ksig->ka.sa.sa_handler; adjustformat(regs); return 0; } static inline void handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler) { switch (regs->d0) { case -ERESTARTNOHAND: if (!has_handler) goto do_restart; regs->d0 = -EINTR; break; case -ERESTART_RESTARTBLOCK: if (!has_handler) { regs->d0 = __NR_restart_syscall; regs->pc -= 2; break; } regs->d0 = -EINTR; break; case -ERESTARTSYS: if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) { regs->d0 = -EINTR; break; } fallthrough; case -ERESTARTNOINTR: do_restart: regs->d0 = regs->orig_d0; regs->pc -= 2; break; } } /* * OK, we're invoking a handler */ static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) { sigset_t *oldset = sigmask_to_save(); int err; /* are we from a system call? */ if (regs->orig_d0 >= 0) /* If so, check system call restarting.. */ handle_restart(regs, &ksig->ka, 1); /* set up the stack frame */ if (ksig->ka.sa.sa_flags & SA_SIGINFO) err = setup_rt_frame(ksig, oldset, regs); else err = setup_frame(ksig, oldset, regs); signal_setup_done(err, ksig, 0); if (test_thread_flag(TIF_DELAYED_TRACE)) { regs->sr &= ~0x8000; send_sig(SIGTRAP, current, 1); } } /* * Note that 'init' is a special process: it doesn't get signals it doesn't * want to handle. Thus you cannot kill init even with a SIGKILL even by * mistake. */ static void do_signal(struct pt_regs *regs) { struct ksignal ksig; current->thread.esp0 = (unsigned long) regs; if (get_signal(&ksig)) { /* Whee! Actually deliver the signal. */ handle_signal(&ksig, regs); return; } /* Did we come from a system call? */ if (regs->orig_d0 >= 0) /* Restart the system call - no handlers present */ handle_restart(regs, NULL, 0); /* If there's no signal to deliver, we just restore the saved mask. */ restore_saved_sigmask(); } void do_notify_resume(struct pt_regs *regs) { if (test_thread_flag(TIF_NOTIFY_SIGNAL) || test_thread_flag(TIF_SIGPENDING)) do_signal(regs); if (test_thread_flag(TIF_NOTIFY_RESUME)) tracehook_notify_resume(regs); }