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-rw-r--r--arch/frv/kernel/signal.c588
1 files changed, 588 insertions, 0 deletions
diff --git a/arch/frv/kernel/signal.c b/arch/frv/kernel/signal.c
new file mode 100644
index 00000000000..d8d8f3d4304
--- /dev/null
+++ b/arch/frv/kernel/signal.c
@@ -0,0 +1,588 @@
+/* signal.c: FRV specific bits of signal handling
+ *
+ * Copyright (C) 2003-5 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ * - Derived from arch/m68k/kernel/signal.c
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.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/personality.h>
+#include <linux/suspend.h>
+#include <asm/ucontext.h>
+#include <asm/uaccess.h>
+#include <asm/cacheflush.h>
+
+#define DEBUG_SIG 0
+
+#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
+
+struct fdpic_func_descriptor {
+ unsigned long text;
+ unsigned long GOT;
+};
+
+asmlinkage int do_signal(struct pt_regs *regs, sigset_t *oldset);
+
+/*
+ * Atomically swap in the new signal mask, and wait for a signal.
+ */
+asmlinkage int sys_sigsuspend(int history0, int history1, old_sigset_t mask)
+{
+ sigset_t saveset;
+
+ mask &= _BLOCKABLE;
+ spin_lock_irq(&current->sighand->siglock);
+ saveset = current->blocked;
+ siginitset(&current->blocked, mask);
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+
+ __frame->gr8 = -EINTR;
+ while (1) {
+ current->state = TASK_INTERRUPTIBLE;
+ schedule();
+ if (do_signal(__frame, &saveset))
+ /* return the signal number as the return value of this function
+ * - this is an utterly evil hack. syscalls should not invoke do_signal()
+ * as entry.S sets regs->gr8 to the return value of the system call
+ * - we can't just use sigpending() as we'd have to discard SIG_IGN signals
+ * and call waitpid() if SIGCHLD needed discarding
+ * - this only works on the i386 because it passes arguments to the signal
+ * handler on the stack, and the return value in EAX is effectively
+ * discarded
+ */
+ return __frame->gr8;
+ }
+}
+
+asmlinkage int sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize)
+{
+ sigset_t saveset, newset;
+
+ /* XXX: Don't preclude handling different sized sigset_t's. */
+ if (sigsetsize != sizeof(sigset_t))
+ return -EINVAL;
+
+ if (copy_from_user(&newset, unewset, sizeof(newset)))
+ return -EFAULT;
+ sigdelsetmask(&newset, ~_BLOCKABLE);
+
+ spin_lock_irq(&current->sighand->siglock);
+ saveset = current->blocked;
+ current->blocked = newset;
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+
+ __frame->gr8 = -EINTR;
+ while (1) {
+ current->state = TASK_INTERRUPTIBLE;
+ schedule();
+ if (do_signal(__frame, &saveset))
+ /* return the signal number as the return value of this function
+ * - this is an utterly evil hack. syscalls should not invoke do_signal()
+ * as entry.S sets regs->gr8 to the return value of the system call
+ * - we can't just use sigpending() as we'd have to discard SIG_IGN signals
+ * and call waitpid() if SIGCHLD needed discarding
+ * - this only works on the i386 because it passes arguments to the signal
+ * handler on the stack, and the return value in EAX is effectively
+ * discarded
+ */
+ return __frame->gr8;
+ }
+}
+
+asmlinkage int sys_sigaction(int sig,
+ const struct old_sigaction __user *act,
+ struct old_sigaction __user *oact)
+{
+ struct k_sigaction new_ka, old_ka;
+ int ret;
+
+ if (act) {
+ old_sigset_t mask;
+ if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
+ __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
+ __get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
+ return -EFAULT;
+ __get_user(new_ka.sa.sa_flags, &act->sa_flags);
+ __get_user(mask, &act->sa_mask);
+ siginitset(&new_ka.sa.sa_mask, mask);
+ }
+
+ ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
+
+ if (!ret && oact) {
+ if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
+ __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
+ __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
+ return -EFAULT;
+ __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
+ __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
+ }
+
+ return ret;
+}
+
+asmlinkage
+int sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss)
+{
+ return do_sigaltstack(uss, uoss, __frame->sp);
+}
+
+
+/*
+ * Do a signal return; undo the signal stack.
+ */
+
+struct sigframe
+{
+ void (*pretcode)(void);
+ int sig;
+ struct sigcontext sc;
+ unsigned long extramask[_NSIG_WORDS-1];
+ uint32_t retcode[2];
+};
+
+struct rt_sigframe
+{
+ void (*pretcode)(void);
+ int sig;
+ struct siginfo *pinfo;
+ void *puc;
+ struct siginfo info;
+ struct ucontext uc;
+ uint32_t retcode[2];
+};
+
+static int restore_sigcontext(struct sigcontext __user *sc, int *_gr8)
+{
+ struct user_context *user = current->thread.user;
+ unsigned long tbr, psr;
+
+ tbr = user->i.tbr;
+ psr = user->i.psr;
+ if (copy_from_user(user, &sc->sc_context, sizeof(sc->sc_context)))
+ goto badframe;
+ user->i.tbr = tbr;
+ user->i.psr = psr;
+
+ restore_user_regs(user);
+
+ user->i.syscallno = -1; /* disable syscall checks */
+
+ *_gr8 = user->i.gr[8];
+ return 0;
+
+ badframe:
+ return 1;
+}
+
+asmlinkage int sys_sigreturn(void)
+{
+ struct sigframe __user *frame = (struct sigframe __user *) __frame->sp;
+ sigset_t set;
+ int gr8;
+
+ if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
+ goto badframe;
+ if (__get_user(set.sig[0], &frame->sc.sc_oldmask))
+ goto badframe;
+
+ if (_NSIG_WORDS > 1 &&
+ __copy_from_user(&set.sig[1], &frame->extramask, sizeof(frame->extramask)))
+ goto badframe;
+
+ sigdelsetmask(&set, ~_BLOCKABLE);
+ spin_lock_irq(&current->sighand->siglock);
+ current->blocked = set;
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+
+ if (restore_sigcontext(&frame->sc, &gr8))
+ goto badframe;
+ return gr8;
+
+ badframe:
+ force_sig(SIGSEGV, current);
+ return 0;
+}
+
+asmlinkage int sys_rt_sigreturn(void)
+{
+ struct rt_sigframe __user *frame = (struct rt_sigframe __user *) __frame->sp;
+ sigset_t set;
+ int gr8;
+
+ if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
+ goto badframe;
+ if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
+ goto badframe;
+
+ sigdelsetmask(&set, ~_BLOCKABLE);
+ spin_lock_irq(&current->sighand->siglock);
+ current->blocked = set;
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+
+ if (restore_sigcontext(&frame->uc.uc_mcontext, &gr8))
+ goto badframe;
+
+ if (do_sigaltstack(&frame->uc.uc_stack, NULL, __frame->sp) == -EFAULT)
+ goto badframe;
+
+ return gr8;
+
+badframe:
+ force_sig(SIGSEGV, current);
+ return 0;
+}
+
+/*
+ * Set up a signal frame
+ */
+static int setup_sigcontext(struct sigcontext __user *sc, unsigned long mask)
+{
+ save_user_regs(current->thread.user);
+
+ if (copy_to_user(&sc->sc_context, current->thread.user, sizeof(sc->sc_context)) != 0)
+ goto badframe;
+
+ /* non-iBCS2 extensions.. */
+ if (__put_user(mask, &sc->sc_oldmask) < 0)
+ goto badframe;
+
+ return 0;
+
+ badframe:
+ return 1;
+}
+
+/*****************************************************************************/
+/*
+ * Determine which stack to use..
+ */
+static inline void __user *get_sigframe(struct k_sigaction *ka,
+ struct pt_regs *regs,
+ size_t frame_size)
+{
+ unsigned long sp;
+
+ /* Default to using normal stack */
+ sp = regs->sp;
+
+ /* This is the X/Open sanctioned signal stack switching. */
+ if (ka->sa.sa_flags & SA_ONSTACK) {
+ if (! on_sig_stack(sp))
+ sp = current->sas_ss_sp + current->sas_ss_size;
+ }
+
+ return (void __user *) ((sp - frame_size) & ~7UL);
+} /* end get_sigframe() */
+
+/*****************************************************************************/
+/*
+ *
+ */
+static void setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, struct pt_regs * regs)
+{
+ struct sigframe __user *frame;
+ int rsig;
+
+ frame = get_sigframe(ka, regs, sizeof(*frame));
+
+ if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+ goto give_sigsegv;
+
+ rsig = sig;
+ if (sig < 32 &&
+ __current_thread_info->exec_domain &&
+ __current_thread_info->exec_domain->signal_invmap)
+ rsig = __current_thread_info->exec_domain->signal_invmap[sig];
+
+ if (__put_user(rsig, &frame->sig) < 0)
+ goto give_sigsegv;
+
+ if (setup_sigcontext(&frame->sc, set->sig[0]))
+ goto give_sigsegv;
+
+ if (_NSIG_WORDS > 1) {
+ if (__copy_to_user(frame->extramask, &set->sig[1],
+ sizeof(frame->extramask)))
+ goto give_sigsegv;
+ }
+
+ /* Set up to return from userspace. If provided, use a stub
+ * already in userspace. */
+ if (ka->sa.sa_flags & SA_RESTORER) {
+ if (__put_user(ka->sa.sa_restorer, &frame->pretcode) < 0)
+ goto give_sigsegv;
+ }
+ else {
+ /* Set up the following code on the stack:
+ * setlos #__NR_sigreturn,gr7
+ * tira gr0,0
+ */
+ if (__put_user((void (*)(void))frame->retcode, &frame->pretcode) ||
+ __put_user(0x8efc0000|__NR_sigreturn, &frame->retcode[0]) ||
+ __put_user(0xc0700000, &frame->retcode[1]))
+ goto give_sigsegv;
+
+ flush_icache_range((unsigned long) frame->retcode,
+ (unsigned long) (frame->retcode + 2));
+ }
+
+ /* set up registers for signal handler */
+ regs->sp = (unsigned long) frame;
+ regs->lr = (unsigned long) &frame->retcode;
+ regs->gr8 = sig;
+
+ if (get_personality & FDPIC_FUNCPTRS) {
+ struct fdpic_func_descriptor __user *funcptr =
+ (struct fdpic_func_descriptor *) ka->sa.sa_handler;
+ __get_user(regs->pc, &funcptr->text);
+ __get_user(regs->gr15, &funcptr->GOT);
+ } else {
+ regs->pc = (unsigned long) ka->sa.sa_handler;
+ regs->gr15 = 0;
+ }
+
+ set_fs(USER_DS);
+
+#if DEBUG_SIG
+ printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
+ sig, current->comm, current->pid, frame, regs->pc, frame->pretcode);
+#endif
+
+ return;
+
+give_sigsegv:
+ if (sig == SIGSEGV)
+ ka->sa.sa_handler = SIG_DFL;
+
+ force_sig(SIGSEGV, current);
+} /* end setup_frame() */
+
+/*****************************************************************************/
+/*
+ *
+ */
+static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
+ sigset_t *set, struct pt_regs * regs)
+{
+ struct rt_sigframe __user *frame;
+ int rsig;
+
+ frame = get_sigframe(ka, regs, sizeof(*frame));
+
+ if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+ goto give_sigsegv;
+
+ rsig = sig;
+ if (sig < 32 &&
+ __current_thread_info->exec_domain &&
+ __current_thread_info->exec_domain->signal_invmap)
+ rsig = __current_thread_info->exec_domain->signal_invmap[sig];
+
+ if (__put_user(rsig, &frame->sig) ||
+ __put_user(&frame->info, &frame->pinfo) ||
+ __put_user(&frame->uc, &frame->puc))
+ goto give_sigsegv;
+
+ if (copy_siginfo_to_user(&frame->info, info))
+ goto give_sigsegv;
+
+ /* Create the ucontext. */
+ if (__put_user(0, &frame->uc.uc_flags) ||
+ __put_user(0, &frame->uc.uc_link) ||
+ __put_user((void*)current->sas_ss_sp, &frame->uc.uc_stack.ss_sp) ||
+ __put_user(sas_ss_flags(regs->sp), &frame->uc.uc_stack.ss_flags) ||
+ __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size))
+ goto give_sigsegv;
+
+ if (setup_sigcontext(&frame->uc.uc_mcontext, set->sig[0]))
+ goto give_sigsegv;
+
+ if (__copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)))
+ goto give_sigsegv;
+
+ /* Set up to return from userspace. If provided, use a stub
+ * already in userspace. */
+ if (ka->sa.sa_flags & SA_RESTORER) {
+ if (__put_user(ka->sa.sa_restorer, &frame->pretcode))
+ goto give_sigsegv;
+ }
+ else {
+ /* Set up the following code on the stack:
+ * setlos #__NR_sigreturn,gr7
+ * tira gr0,0
+ */
+ if (__put_user((void (*)(void))frame->retcode, &frame->pretcode) ||
+ __put_user(0x8efc0000|__NR_rt_sigreturn, &frame->retcode[0]) ||
+ __put_user(0xc0700000, &frame->retcode[1]))
+ goto give_sigsegv;
+
+ flush_icache_range((unsigned long) frame->retcode,
+ (unsigned long) (frame->retcode + 2));
+ }
+
+ /* Set up registers for signal handler */
+ regs->sp = (unsigned long) frame;
+ regs->lr = (unsigned long) &frame->retcode;
+ regs->gr8 = sig;
+ regs->gr9 = (unsigned long) &frame->info;
+
+ if (get_personality & FDPIC_FUNCPTRS) {
+ struct fdpic_func_descriptor *funcptr =
+ (struct fdpic_func_descriptor __user *) ka->sa.sa_handler;
+ __get_user(regs->pc, &funcptr->text);
+ __get_user(regs->gr15, &funcptr->GOT);
+ } else {
+ regs->pc = (unsigned long) ka->sa.sa_handler;
+ regs->gr15 = 0;
+ }
+
+ set_fs(USER_DS);
+
+#if DEBUG_SIG
+ printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",
+ sig, current->comm, current->pid, frame, regs->pc, frame->pretcode);
+#endif
+
+ return;
+
+give_sigsegv:
+ if (sig == SIGSEGV)
+ ka->sa.sa_handler = SIG_DFL;
+ force_sig(SIGSEGV, current);
+
+} /* end setup_rt_frame() */
+
+/*****************************************************************************/
+/*
+ * OK, we're invoking a handler
+ */
+static void handle_signal(unsigned long sig, siginfo_t *info,
+ struct k_sigaction *ka, sigset_t *oldset,
+ struct pt_regs *regs)
+{
+ /* Are we from a system call? */
+ if (in_syscall(regs)) {
+ /* If so, check system call restarting.. */
+ switch (regs->gr8) {
+ case -ERESTART_RESTARTBLOCK:
+ case -ERESTARTNOHAND:
+ regs->gr8 = -EINTR;
+ break;
+
+ case -ERESTARTSYS:
+ if (!(ka->sa.sa_flags & SA_RESTART)) {
+ regs->gr8 = -EINTR;
+ break;
+ }
+ /* fallthrough */
+ case -ERESTARTNOINTR:
+ regs->gr8 = regs->orig_gr8;
+ regs->pc -= 4;
+ }
+ }
+
+ /* Set up the stack frame */
+ if (ka->sa.sa_flags & SA_SIGINFO)
+ setup_rt_frame(sig, ka, info, oldset, regs);
+ else
+ setup_frame(sig, ka, oldset, regs);
+
+ if (!(ka->sa.sa_flags & SA_NODEFER)) {
+ spin_lock_irq(&current->sighand->siglock);
+ sigorsets(&current->blocked, &current->blocked, &ka->sa.sa_mask);
+ sigaddset(&current->blocked, sig);
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+ }
+} /* end handle_signal() */
+
+/*****************************************************************************/
+/*
+ * 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.
+ */
+int do_signal(struct pt_regs *regs, sigset_t *oldset)
+{
+ struct k_sigaction ka;
+ siginfo_t info;
+ int signr;
+
+ /*
+ * We want the common case to go fast, which
+ * is why we may in certain cases get here from
+ * kernel mode. Just return without doing anything
+ * if so.
+ */
+ if (!user_mode(regs))
+ return 1;
+
+ if (current->flags & PF_FREEZE) {
+ refrigerator(0);
+ goto no_signal;
+ }
+
+ if (!oldset)
+ oldset = &current->blocked;
+
+ signr = get_signal_to_deliver(&info, &ka, regs, NULL);
+ if (signr > 0) {
+ handle_signal(signr, &info, &ka, oldset, regs);
+ return 1;
+ }
+
+ no_signal:
+ /* Did we come from a system call? */
+ if (regs->syscallno >= 0) {
+ /* Restart the system call - no handlers present */
+ if (regs->gr8 == -ERESTARTNOHAND ||
+ regs->gr8 == -ERESTARTSYS ||
+ regs->gr8 == -ERESTARTNOINTR) {
+ regs->gr8 = regs->orig_gr8;
+ regs->pc -= 4;
+ }
+
+ if (regs->gr8 == -ERESTART_RESTARTBLOCK){
+ regs->gr8 = __NR_restart_syscall;
+ regs->pc -= 4;
+ }
+ }
+
+ return 0;
+} /* end do_signal() */
+
+/*****************************************************************************/
+/*
+ * notification of userspace execution resumption
+ * - triggered by current->work.notify_resume
+ */
+asmlinkage void do_notify_resume(__u32 thread_info_flags)
+{
+ /* pending single-step? */
+ if (thread_info_flags & _TIF_SINGLESTEP)
+ clear_thread_flag(TIF_SINGLESTEP);
+
+ /* deal with pending signal delivery */
+ if (thread_info_flags & _TIF_SIGPENDING)
+ do_signal(__frame, NULL);
+
+} /* end do_notify_resume() */
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