diff options
Diffstat (limited to 'arch/sparc/kernel/signal_32.c')
-rw-r--r-- | arch/sparc/kernel/signal_32.c | 631 |
1 files changed, 631 insertions, 0 deletions
diff --git a/arch/sparc/kernel/signal_32.c b/arch/sparc/kernel/signal_32.c new file mode 100644 index 0000000..c94f91c --- /dev/null +++ b/arch/sparc/kernel/signal_32.c @@ -0,0 +1,631 @@ +/* linux/arch/sparc/kernel/signal.c + * + * Copyright (C) 1991, 1992 Linus Torvalds + * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu) + * Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx) + * Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be) + */ + +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/signal.h> +#include <linux/errno.h> +#include <linux/wait.h> +#include <linux/ptrace.h> +#include <linux/unistd.h> +#include <linux/mm.h> +#include <linux/tty.h> +#include <linux/smp.h> +#include <linux/binfmts.h> /* do_coredum */ +#include <linux/bitops.h> +#include <linux/tracehook.h> + +#include <asm/uaccess.h> +#include <asm/ptrace.h> +#include <asm/pgalloc.h> +#include <asm/pgtable.h> +#include <asm/cacheflush.h> /* flush_sig_insns */ + +#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) + +extern void fpsave(unsigned long *fpregs, unsigned long *fsr, + void *fpqueue, unsigned long *fpqdepth); +extern void fpload(unsigned long *fpregs, unsigned long *fsr); + +struct signal_frame { + struct sparc_stackf ss; + __siginfo_t info; + __siginfo_fpu_t __user *fpu_save; + unsigned long insns[2] __attribute__ ((aligned (8))); + unsigned int extramask[_NSIG_WORDS - 1]; + unsigned int extra_size; /* Should be 0 */ + __siginfo_fpu_t fpu_state; +}; + +struct rt_signal_frame { + struct sparc_stackf ss; + siginfo_t info; + struct pt_regs regs; + sigset_t mask; + __siginfo_fpu_t __user *fpu_save; + unsigned int insns[2]; + stack_t stack; + unsigned int extra_size; /* Should be 0 */ + __siginfo_fpu_t fpu_state; +}; + +/* Align macros */ +#define SF_ALIGNEDSZ (((sizeof(struct signal_frame) + 7) & (~7))) +#define RT_ALIGNEDSZ (((sizeof(struct rt_signal_frame) + 7) & (~7))) + +static int _sigpause_common(old_sigset_t set) +{ + set &= _BLOCKABLE; + spin_lock_irq(¤t->sighand->siglock); + current->saved_sigmask = current->blocked; + siginitset(¤t->blocked, set); + recalc_sigpending(); + spin_unlock_irq(¤t->sighand->siglock); + + current->state = TASK_INTERRUPTIBLE; + schedule(); + set_thread_flag(TIF_RESTORE_SIGMASK); + + return -ERESTARTNOHAND; +} + +asmlinkage int sys_sigsuspend(old_sigset_t set) +{ + return _sigpause_common(set); +} + +static inline int +restore_fpu_state(struct pt_regs *regs, __siginfo_fpu_t __user *fpu) +{ + int err; +#ifdef CONFIG_SMP + if (test_tsk_thread_flag(current, TIF_USEDFPU)) + regs->psr &= ~PSR_EF; +#else + if (current == last_task_used_math) { + last_task_used_math = NULL; + regs->psr &= ~PSR_EF; + } +#endif + set_used_math(); + clear_tsk_thread_flag(current, TIF_USEDFPU); + + if (!access_ok(VERIFY_READ, fpu, sizeof(*fpu))) + return -EFAULT; + + err = __copy_from_user(¤t->thread.float_regs[0], &fpu->si_float_regs[0], + (sizeof(unsigned long) * 32)); + err |= __get_user(current->thread.fsr, &fpu->si_fsr); + err |= __get_user(current->thread.fpqdepth, &fpu->si_fpqdepth); + if (current->thread.fpqdepth != 0) + err |= __copy_from_user(¤t->thread.fpqueue[0], + &fpu->si_fpqueue[0], + ((sizeof(unsigned long) + + (sizeof(unsigned long *)))*16)); + return err; +} + +asmlinkage void do_sigreturn(struct pt_regs *regs) +{ + struct signal_frame __user *sf; + unsigned long up_psr, pc, npc; + sigset_t set; + __siginfo_fpu_t __user *fpu_save; + int err; + + /* Always make any pending restarted system calls return -EINTR */ + current_thread_info()->restart_block.fn = do_no_restart_syscall; + + synchronize_user_stack(); + + sf = (struct signal_frame __user *) regs->u_regs[UREG_FP]; + + /* 1. Make sure we are not getting garbage from the user */ + if (!access_ok(VERIFY_READ, sf, sizeof(*sf))) + goto segv_and_exit; + + if (((unsigned long) sf) & 3) + goto segv_and_exit; + + err = __get_user(pc, &sf->info.si_regs.pc); + err |= __get_user(npc, &sf->info.si_regs.npc); + + if ((pc | npc) & 3) + goto segv_and_exit; + + /* 2. Restore the state */ + up_psr = regs->psr; + err |= __copy_from_user(regs, &sf->info.si_regs, sizeof(struct pt_regs)); + + /* User can only change condition codes and FPU enabling in %psr. */ + regs->psr = (up_psr & ~(PSR_ICC | PSR_EF)) + | (regs->psr & (PSR_ICC | PSR_EF)); + + /* Prevent syscall restart. */ + pt_regs_clear_syscall(regs); + + err |= __get_user(fpu_save, &sf->fpu_save); + + if (fpu_save) + err |= restore_fpu_state(regs, fpu_save); + + /* This is pretty much atomic, no amount locking would prevent + * the races which exist anyways. + */ + err |= __get_user(set.sig[0], &sf->info.si_mask); + err |= __copy_from_user(&set.sig[1], &sf->extramask, + (_NSIG_WORDS-1) * sizeof(unsigned int)); + + if (err) + goto segv_and_exit; + + sigdelsetmask(&set, ~_BLOCKABLE); + spin_lock_irq(¤t->sighand->siglock); + current->blocked = set; + recalc_sigpending(); + spin_unlock_irq(¤t->sighand->siglock); + return; + +segv_and_exit: + force_sig(SIGSEGV, current); +} + +asmlinkage void do_rt_sigreturn(struct pt_regs *regs) +{ + struct rt_signal_frame __user *sf; + unsigned int psr, pc, npc; + __siginfo_fpu_t __user *fpu_save; + mm_segment_t old_fs; + sigset_t set; + stack_t st; + int err; + + synchronize_user_stack(); + sf = (struct rt_signal_frame __user *) regs->u_regs[UREG_FP]; + if (!access_ok(VERIFY_READ, sf, sizeof(*sf)) || + (((unsigned long) sf) & 0x03)) + goto segv; + + err = __get_user(pc, &sf->regs.pc); + err |= __get_user(npc, &sf->regs.npc); + err |= ((pc | npc) & 0x03); + + err |= __get_user(regs->y, &sf->regs.y); + err |= __get_user(psr, &sf->regs.psr); + + err |= __copy_from_user(®s->u_regs[UREG_G1], + &sf->regs.u_regs[UREG_G1], 15 * sizeof(u32)); + + regs->psr = (regs->psr & ~PSR_ICC) | (psr & PSR_ICC); + + /* Prevent syscall restart. */ + pt_regs_clear_syscall(regs); + + err |= __get_user(fpu_save, &sf->fpu_save); + + if (fpu_save) + err |= restore_fpu_state(regs, fpu_save); + err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t)); + + err |= __copy_from_user(&st, &sf->stack, sizeof(stack_t)); + + if (err) + goto segv; + + regs->pc = pc; + regs->npc = npc; + + /* It is more difficult to avoid calling this function than to + * call it and ignore errors. + */ + old_fs = get_fs(); + set_fs(KERNEL_DS); + do_sigaltstack((const stack_t __user *) &st, NULL, (unsigned long)sf); + set_fs(old_fs); + + sigdelsetmask(&set, ~_BLOCKABLE); + spin_lock_irq(¤t->sighand->siglock); + current->blocked = set; + recalc_sigpending(); + spin_unlock_irq(¤t->sighand->siglock); + return; +segv: + force_sig(SIGSEGV, current); +} + +/* Checks if the fp is valid */ +static inline int invalid_frame_pointer(void __user *fp, int fplen) +{ + if ((((unsigned long) fp) & 7) || + !__access_ok((unsigned long)fp, fplen) || + ((sparc_cpu_model == sun4 || sparc_cpu_model == sun4c) && + ((unsigned long) fp < 0xe0000000 && (unsigned long) fp >= 0x20000000))) + return 1; + + return 0; +} + +static inline void __user *get_sigframe(struct sigaction *sa, struct pt_regs *regs, unsigned long framesize) +{ + unsigned long sp = regs->u_regs[UREG_FP]; + + /* + * If we are on the alternate signal stack and would overflow it, don't. + * Return an always-bogus address instead so we will die with SIGSEGV. + */ + if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize))) + return (void __user *) -1L; + + /* This is the X/Open sanctioned signal stack switching. */ + if (sa->sa_flags & SA_ONSTACK) { + if (sas_ss_flags(sp) == 0) + sp = current->sas_ss_sp + current->sas_ss_size; + } + + /* Always align the stack frame. This handles two cases. First, + * sigaltstack need not be mindful of platform specific stack + * alignment. Second, if we took this signal because the stack + * is not aligned properly, we'd like to take the signal cleanly + * and report that. + */ + sp &= ~7UL; + + return (void __user *)(sp - framesize); +} + +static inline int +save_fpu_state(struct pt_regs *regs, __siginfo_fpu_t __user *fpu) +{ + int err = 0; +#ifdef CONFIG_SMP + if (test_tsk_thread_flag(current, TIF_USEDFPU)) { + put_psr(get_psr() | PSR_EF); + fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr, + ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth); + regs->psr &= ~(PSR_EF); + clear_tsk_thread_flag(current, TIF_USEDFPU); + } +#else + if (current == last_task_used_math) { + put_psr(get_psr() | PSR_EF); + fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr, + ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth); + last_task_used_math = NULL; + regs->psr &= ~(PSR_EF); + } +#endif + err |= __copy_to_user(&fpu->si_float_regs[0], + ¤t->thread.float_regs[0], + (sizeof(unsigned long) * 32)); + err |= __put_user(current->thread.fsr, &fpu->si_fsr); + err |= __put_user(current->thread.fpqdepth, &fpu->si_fpqdepth); + if (current->thread.fpqdepth != 0) + err |= __copy_to_user(&fpu->si_fpqueue[0], + ¤t->thread.fpqueue[0], + ((sizeof(unsigned long) + + (sizeof(unsigned long *)))*16)); + clear_used_math(); + return err; +} + +static void setup_frame(struct k_sigaction *ka, struct pt_regs *regs, + int signo, sigset_t *oldset) +{ + struct signal_frame __user *sf; + int sigframe_size, err; + + /* 1. Make sure everything is clean */ + synchronize_user_stack(); + + sigframe_size = SF_ALIGNEDSZ; + if (!used_math()) + sigframe_size -= sizeof(__siginfo_fpu_t); + + sf = (struct signal_frame __user *) + get_sigframe(&ka->sa, regs, sigframe_size); + + if (invalid_frame_pointer(sf, sigframe_size)) + goto sigill_and_return; + + if (current_thread_info()->w_saved != 0) + goto sigill_and_return; + + /* 2. Save the current process state */ + err = __copy_to_user(&sf->info.si_regs, regs, sizeof(struct pt_regs)); + + err |= __put_user(0, &sf->extra_size); + + if (used_math()) { + err |= save_fpu_state(regs, &sf->fpu_state); + err |= __put_user(&sf->fpu_state, &sf->fpu_save); + } else { + err |= __put_user(0, &sf->fpu_save); + } + + err |= __put_user(oldset->sig[0], &sf->info.si_mask); + err |= __copy_to_user(sf->extramask, &oldset->sig[1], + (_NSIG_WORDS - 1) * sizeof(unsigned int)); + err |= __copy_to_user(sf, (char *) regs->u_regs[UREG_FP], + sizeof(struct reg_window)); + if (err) + goto sigsegv; + + /* 3. signal handler back-trampoline and parameters */ + regs->u_regs[UREG_FP] = (unsigned long) sf; + regs->u_regs[UREG_I0] = signo; + regs->u_regs[UREG_I1] = (unsigned long) &sf->info; + regs->u_regs[UREG_I2] = (unsigned long) &sf->info; + + /* 4. signal handler */ + regs->pc = (unsigned long) ka->sa.sa_handler; + regs->npc = (regs->pc + 4); + + /* 5. return to kernel instructions */ + if (ka->ka_restorer) + regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer; + else { + regs->u_regs[UREG_I7] = (unsigned long)(&(sf->insns[0]) - 2); + + /* mov __NR_sigreturn, %g1 */ + err |= __put_user(0x821020d8, &sf->insns[0]); + + /* t 0x10 */ + err |= __put_user(0x91d02010, &sf->insns[1]); + if (err) + goto sigsegv; + + /* Flush instruction space. */ + flush_sig_insns(current->mm, (unsigned long) &(sf->insns[0])); + } + return; + +sigill_and_return: + do_exit(SIGILL); +sigsegv: + force_sigsegv(signo, current); +} + +static void setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs, + int signo, sigset_t *oldset, siginfo_t *info) +{ + struct rt_signal_frame __user *sf; + int sigframe_size; + unsigned int psr; + int err; + + synchronize_user_stack(); + sigframe_size = RT_ALIGNEDSZ; + if (!used_math()) + sigframe_size -= sizeof(__siginfo_fpu_t); + sf = (struct rt_signal_frame __user *) + get_sigframe(&ka->sa, regs, sigframe_size); + if (invalid_frame_pointer(sf, sigframe_size)) + goto sigill; + if (current_thread_info()->w_saved != 0) + goto sigill; + + err = __put_user(regs->pc, &sf->regs.pc); + err |= __put_user(regs->npc, &sf->regs.npc); + err |= __put_user(regs->y, &sf->regs.y); + psr = regs->psr; + if (used_math()) + psr |= PSR_EF; + err |= __put_user(psr, &sf->regs.psr); + err |= __copy_to_user(&sf->regs.u_regs, regs->u_regs, sizeof(regs->u_regs)); + err |= __put_user(0, &sf->extra_size); + + if (psr & PSR_EF) { + err |= save_fpu_state(regs, &sf->fpu_state); + err |= __put_user(&sf->fpu_state, &sf->fpu_save); + } else { + err |= __put_user(0, &sf->fpu_save); + } + err |= __copy_to_user(&sf->mask, &oldset->sig[0], sizeof(sigset_t)); + + /* Setup sigaltstack */ + err |= __put_user(current->sas_ss_sp, &sf->stack.ss_sp); + err |= __put_user(sas_ss_flags(regs->u_regs[UREG_FP]), &sf->stack.ss_flags); + err |= __put_user(current->sas_ss_size, &sf->stack.ss_size); + + err |= __copy_to_user(sf, (char *) regs->u_regs[UREG_FP], + sizeof(struct reg_window)); + + err |= copy_siginfo_to_user(&sf->info, info); + + if (err) + goto sigsegv; + + regs->u_regs[UREG_FP] = (unsigned long) sf; + regs->u_regs[UREG_I0] = signo; + regs->u_regs[UREG_I1] = (unsigned long) &sf->info; + regs->u_regs[UREG_I2] = (unsigned long) &sf->regs; + + regs->pc = (unsigned long) ka->sa.sa_handler; + regs->npc = (regs->pc + 4); + + if (ka->ka_restorer) + regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer; + else { + regs->u_regs[UREG_I7] = (unsigned long)(&(sf->insns[0]) - 2); + + /* mov __NR_sigreturn, %g1 */ + err |= __put_user(0x821020d8, &sf->insns[0]); + + /* t 0x10 */ + err |= __put_user(0x91d02010, &sf->insns[1]); + if (err) + goto sigsegv; + + /* Flush instruction space. */ + flush_sig_insns(current->mm, (unsigned long) &(sf->insns[0])); + } + return; + +sigill: + do_exit(SIGILL); +sigsegv: + force_sigsegv(signo, current); +} + +static inline void +handle_signal(unsigned long signr, struct k_sigaction *ka, + siginfo_t *info, sigset_t *oldset, struct pt_regs *regs) +{ + if (ka->sa.sa_flags & SA_SIGINFO) + setup_rt_frame(ka, regs, signr, oldset, info); + else + setup_frame(ka, regs, signr, oldset); + + spin_lock_irq(¤t->sighand->siglock); + sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask); + if (!(ka->sa.sa_flags & SA_NOMASK)) + sigaddset(¤t->blocked, signr); + recalc_sigpending(); + spin_unlock_irq(¤t->sighand->siglock); +} + +static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs, + struct sigaction *sa) +{ + switch(regs->u_regs[UREG_I0]) { + case ERESTART_RESTARTBLOCK: + case ERESTARTNOHAND: + no_system_call_restart: + regs->u_regs[UREG_I0] = EINTR; + regs->psr |= PSR_C; + break; + case ERESTARTSYS: + if (!(sa->sa_flags & SA_RESTART)) + goto no_system_call_restart; + /* fallthrough */ + case ERESTARTNOINTR: + regs->u_regs[UREG_I0] = orig_i0; + regs->pc -= 4; + regs->npc -= 4; + } +} + +/* 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, unsigned long orig_i0) +{ + struct k_sigaction ka; + int restart_syscall; + sigset_t *oldset; + siginfo_t info; + int signr; + + if (pt_regs_is_syscall(regs) && (regs->psr & PSR_C)) + restart_syscall = 1; + else + restart_syscall = 0; + + if (test_thread_flag(TIF_RESTORE_SIGMASK)) + oldset = ¤t->saved_sigmask; + else + oldset = ¤t->blocked; + + signr = get_signal_to_deliver(&info, &ka, regs, NULL); + + /* If the debugger messes with the program counter, it clears + * the software "in syscall" bit, directing us to not perform + * a syscall restart. + */ + if (restart_syscall && !pt_regs_is_syscall(regs)) + restart_syscall = 0; + + if (signr > 0) { + if (restart_syscall) + syscall_restart(orig_i0, regs, &ka.sa); + handle_signal(signr, &ka, &info, oldset, regs); + + /* a signal was successfully delivered; the saved + * sigmask will have been stored in the signal frame, + * and will be restored by sigreturn, so we can simply + * clear the TIF_RESTORE_SIGMASK flag. + */ + if (test_thread_flag(TIF_RESTORE_SIGMASK)) + clear_thread_flag(TIF_RESTORE_SIGMASK); + + tracehook_signal_handler(signr, &info, &ka, regs, 0); + return; + } + if (restart_syscall && + (regs->u_regs[UREG_I0] == ERESTARTNOHAND || + regs->u_regs[UREG_I0] == ERESTARTSYS || + regs->u_regs[UREG_I0] == ERESTARTNOINTR)) { + /* replay the system call when we are done */ + regs->u_regs[UREG_I0] = orig_i0; + regs->pc -= 4; + regs->npc -= 4; + } + if (restart_syscall && + regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) { + regs->u_regs[UREG_G1] = __NR_restart_syscall; + regs->pc -= 4; + regs->npc -= 4; + } + + /* if there's no signal to deliver, we just put the saved sigmask + * back + */ + if (test_thread_flag(TIF_RESTORE_SIGMASK)) { + clear_thread_flag(TIF_RESTORE_SIGMASK); + sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); + } +} + +void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, + unsigned long thread_info_flags) +{ + if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK)) + do_signal(regs, orig_i0); + if (thread_info_flags & _TIF_NOTIFY_RESUME) { + clear_thread_flag(TIF_NOTIFY_RESUME); + tracehook_notify_resume(regs); + } +} + +asmlinkage int +do_sys_sigstack(struct sigstack __user *ssptr, struct sigstack __user *ossptr, + unsigned long sp) +{ + int ret = -EFAULT; + + /* First see if old state is wanted. */ + if (ossptr) { + if (put_user(current->sas_ss_sp + current->sas_ss_size, + &ossptr->the_stack) || + __put_user(on_sig_stack(sp), &ossptr->cur_status)) + goto out; + } + + /* Now see if we want to update the new state. */ + if (ssptr) { + char *ss_sp; + + if (get_user(ss_sp, &ssptr->the_stack)) + goto out; + /* If the current stack was set with sigaltstack, don't + swap stacks while we are on it. */ + ret = -EPERM; + if (current->sas_ss_sp && on_sig_stack(sp)) + goto out; + + /* Since we don't know the extent of the stack, and we don't + track onstack-ness, but rather calculate it, we must + presume a size. Ho hum this interface is lossy. */ + current->sas_ss_sp = (unsigned long)ss_sp - SIGSTKSZ; + current->sas_ss_size = SIGSTKSZ; + } + ret = 0; +out: + return ret; +} |