--- /dev/null
+/*
+ * linux/arch/h8300/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.
+ */
+
+/*
+ * uClinux H8/300 support by Yoshinori Sato <ysato@users.sourceforge.jp>
+ * and David McCullough <davidm@snapgear.com>
+ *
+ * Based on
+ * Linux/m68k by Hamish Macdonald
+ */
+
+/*
+ * ++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 <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/syscalls.h>
+#include <linux/errno.h>
+#include <linux/wait.h>
+#include <linux/ptrace.h>
+#include <linux/unistd.h>
+#include <linux/stddef.h>
+#include <linux/highuid.h>
+#include <linux/personality.h>
+#include <linux/tty.h>
+#include <linux/binfmts.h>
+#include <linux/tracehook.h>
+
+#include <asm/setup.h>
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/traps.h>
+#include <asm/ucontext.h>
+
+/*
+ * 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 rt_sigframe {
+ long dummy_er0;
+ long dummy_vector;
+#if defined(CONFIG_CPU_H8S)
+ short dummy_exr;
+#endif
+ long dummy_pc;
+ char *pretcode;
+ struct siginfo *pinfo;
+ void *puc;
+ unsigned char retcode[8];
+ struct siginfo info;
+ struct ucontext uc;
+ int sig;
+} __packed __aligned(2);
+
+static inline int
+restore_sigcontext(struct sigcontext *usc, int *pd0)
+{
+ struct pt_regs *regs = current_pt_regs();
+ int err = 0;
+ unsigned int ccr;
+ unsigned int usp;
+ unsigned int er0;
+
+ /* Always make any pending restarted system calls return -EINTR */
+ current_thread_info()->restart_block.fn = do_no_restart_syscall;
+
+ /* restore passed registers */
+#define COPY(r) do { err |= get_user(regs->r, &usc->sc_##r); } while (0)
+ COPY(er1);
+ COPY(er2);
+ COPY(er3);
+ COPY(er5);
+ COPY(pc);
+ ccr = regs->ccr & 0x10;
+ COPY(ccr);
+#undef COPY
+ regs->ccr &= 0xef;
+ regs->ccr |= ccr;
+ regs->orig_er0 = -1; /* disable syscall checks */
+ err |= __get_user(usp, &usc->sc_usp);
+ wrusp(usp);
+
+ err |= __get_user(er0, &usc->sc_er0);
+ *pd0 = er0;
+ return err;
+}
+
+asmlinkage int sys_rt_sigreturn(void)
+{
+ unsigned long usp = rdusp();
+ struct rt_sigframe *frame = (struct rt_sigframe *)(usp - 4);
+ sigset_t set;
+ int er0;
+
+ if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
+ goto badframe;
+ if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
+ goto badframe;
+
+ set_current_blocked(&set);
+
+ if (restore_sigcontext(&frame->uc.uc_mcontext, &er0))
+ goto badframe;
+
+ if (restore_altstack(&frame->uc.uc_stack))
+ goto badframe;
+
+ return er0;
+
+badframe:
+ force_sig(SIGSEGV, current);
+ return 0;
+}
+
+static int setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
+ unsigned long mask)
+{
+ int err = 0;
+
+ err |= __put_user(regs->er0, &sc->sc_er0);
+ err |= __put_user(regs->er1, &sc->sc_er1);
+ err |= __put_user(regs->er2, &sc->sc_er2);
+ err |= __put_user(regs->er3, &sc->sc_er3);
+ err |= __put_user(regs->er4, &sc->sc_er4);
+ err |= __put_user(regs->er5, &sc->sc_er5);
+ err |= __put_user(regs->er6, &sc->sc_er6);
+ err |= __put_user(rdusp(), &sc->sc_usp);
+ err |= __put_user(regs->pc, &sc->sc_pc);
+ err |= __put_user(regs->ccr, &sc->sc_ccr);
+ err |= __put_user(mask, &sc->sc_mask);
+
+ return err;
+}
+
+static inline void __user *
+get_sigframe(struct ksignal *ksig, struct pt_regs *regs, size_t frame_size)
+{
+ return (void __user *)((sigsp(rdusp(), ksig) - frame_size) & -8UL);
+}
+
+static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
+ struct pt_regs *regs)
+{
+ struct rt_sigframe *frame;
+ int err = 0;
+ unsigned char *ret;
+
+ frame = get_sigframe(ksig, regs, sizeof(*frame));
+
+ if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+ return -EFAULT;
+
+ if (ksig->ka.sa.sa_flags & SA_SIGINFO)
+ err |= copy_siginfo_to_user(&frame->info, &ksig->info);
+
+ /* Create the ucontext. */
+ err |= __put_user(0, &frame->uc.uc_flags);
+ err |= __put_user(0, &frame->uc.uc_link);
+ err |= __save_altstack(&frame->uc.uc_stack, rdusp());
+ err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, set->sig[0]);
+ err |= copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+ if (err)
+ return -EFAULT;
+
+ /* Set up to return from userspace. */
+ ret = frame->retcode;
+ if (ksig->ka.sa.sa_flags & SA_RESTORER)
+ ret = (unsigned char *)(ksig->ka.sa.sa_restorer);
+ else {
+ /* sub.l er0,er0; mov.b #__NR_rt_sigreturn,r0l; trapa #0 */
+ err |= __put_user(0x1a80f800 + (__NR_rt_sigreturn & 0xff),
+ (unsigned long *)(frame->retcode + 0));
+ err |= __put_user(0x5700,
+ (unsigned short *)(frame->retcode + 4));
+ }
+ err |= __put_user(ret, &frame->pretcode);
+
+ if (err)
+ return -EFAULT;
+
+ /* Set up registers for signal handler */
+ wrusp((unsigned long) frame);
+ regs->pc = (unsigned long) ksig->ka.sa.sa_handler;
+ regs->er0 = ksig->sig;
+ regs->er1 = (unsigned long)&(frame->info);
+ regs->er2 = (unsigned long)&frame->uc;
+ regs->er5 = current->mm->start_data; /* GOT base */
+
+ return 0;
+}
+
+static void
+handle_restart(struct pt_regs *regs, struct k_sigaction *ka)
+{
+ switch (regs->er0) {
+ case -ERESTARTNOHAND:
+ if (!ka)
+ goto do_restart;
+ regs->er0 = -EINTR;
+ break;
+ case -ERESTART_RESTARTBLOCK:
+ if (!ka) {
+ regs->er0 = __NR_restart_syscall;
+ regs->pc -= 2;
+ } else
+ regs->er0 = -EINTR;
+ break;
+ case -ERESTARTSYS:
+ if (!(ka->sa.sa_flags & SA_RESTART)) {
+ regs->er0 = -EINTR;
+ break;
+ }
+ /* fallthrough */
+ case -ERESTARTNOINTR:
+do_restart:
+ regs->er0 = regs->orig_er0;
+ 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 ret;
+ /* are we from a system call? */
+ if (regs->orig_er0 >= 0)
+ handle_restart(regs, &ksig->ka);
+
+ ret = setup_rt_frame(ksig, oldset, regs);
+
+ signal_setup_done(ret, ksig, 0);
+}
+
+/*
+ * 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_er0 >= 0)
+ handle_restart(regs, NULL);
+
+ /* If there's no signal to deliver, we just restore the saved mask. */
+ restore_saved_sigmask();
+}
+
+asmlinkage void do_notify_resume(struct pt_regs *regs, u32 thread_info_flags)
+{
+ if (thread_info_flags & _TIF_SIGPENDING)
+ do_signal(regs);
+
+ if (thread_info_flags & _TIF_NOTIFY_RESUME) {
+ clear_thread_flag(TIF_NOTIFY_RESUME);
+ tracehook_notify_resume(regs);
+ }
+}
Code Review / kvmfornfv.git / blobdiff