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authorRalf Baechle <ralf@linux-mips.org>1998-03-17 22:05:47 +0000
committerRalf Baechle <ralf@linux-mips.org>1998-03-17 22:05:47 +0000
commit27cfca1ec98e91261b1a5355d10a8996464b63af (patch)
tree8e895a53e372fa682b4c0a585b9377d67ed70d0e /arch/arm/kernel/signal.c
parent6a76fb7214c477ccf6582bd79c5b4ccc4f9c41b1 (diff)
Look Ma' what I found on my harddisk ...
o New faster syscalls for 2.1.x, too o Upgrade to 2.1.89. Don't try to run this. It's flaky as hell. But feel free to debug ...
Diffstat (limited to 'arch/arm/kernel/signal.c')
-rw-r--r--arch/arm/kernel/signal.c515
1 files changed, 515 insertions, 0 deletions
diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
new file mode 100644
index 000000000..0cba3dd07
--- /dev/null
+++ b/arch/arm/kernel/signal.c
@@ -0,0 +1,515 @@
+/*
+ * linux/arch/arm/kernel/signal.c
+ *
+ * Copyright (C) 1995, 1996 Russell King
+ */
+
+#include <linux/config.h> /* for CONFIG_CPU_ARM6 and CONFIG_CPU_SA110 */
+#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/stddef.h>
+
+#include <asm/ucontext.h>
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+
+#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
+
+#define SWI_SYS_SIGRETURN (0xef000000|(__NR_sigreturn))
+#define SWI_SYS_RT_SIGRETURN (0xef000000|(__NR_rt_sigreturn))
+
+asmlinkage int sys_wait4(pid_t pid, unsigned long * stat_addr,
+ int options, unsigned long *ru);
+asmlinkage int do_signal(sigset_t *oldset, struct pt_regs * regs);
+extern int ptrace_cancel_bpt (struct task_struct *);
+extern int ptrace_set_bpt (struct task_struct *);
+
+/*
+ * atomically swap in the new signal mask, and wait for a signal.
+ */
+asmlinkage int sys_sigsuspend(int restart, unsigned long oldmask, old_sigset_t mask, struct pt_regs *regs)
+{
+
+ sigset_t saveset;
+
+ mask &= _BLOCKABLE;
+ spin_lock_irq(&current->sigmask_lock);
+ saveset = current->blocked;
+ siginitset(&current->blocked, mask);
+ recalc_sigpending(current);
+ spin_unlock_irq(&current->sigmask_lock);
+ regs->ARM_r0 = -EINTR;
+
+ while (1) {
+ current->state = TASK_INTERRUPTIBLE;
+ schedule();
+ if (do_signal(&saveset, regs))
+ return regs->ARM_r0;
+ }
+}
+
+asmlinkage int
+sys_rt_sigsuspend(sigset_t *unewset, size_t sigsetsize, struct pt_regs *regs)
+{
+ 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->sigmask_lock);
+ saveset = current->blocked;
+ current->blocked = newset;
+ recalc_sigpending(current);
+ spin_unlock_irq(&current->sigmask_lock);
+ regs->ARM_r0 = -EINTR;
+
+ while (1) {
+ current->state = TASK_INTERRUPTIBLE;
+ schedule();
+ if (do_signal(&saveset, regs))
+ return regs->ARM_r0;
+ }
+}
+
+asmlinkage int
+sys_sigaction(int sig, const struct old_sigaction *act,
+ struct old_sigaction *oact)
+{
+ struct k_sigaction new_ka, old_ka;
+ int ret;
+
+ if (act) {
+ old_sigset_t mask;
+ if (verify_area(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 (verify_area(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;
+}
+
+/*
+ * Do a signal return; undo the signal stack.
+ */
+struct sigframe
+{
+ struct sigcontext sc;
+ unsigned long extramask[_NSIG_WORDS-1];
+ unsigned long retcode;
+};
+
+struct rt_sigframe
+{
+ struct siginfo *pinfo;
+ void *puc;
+ struct siginfo info;
+ struct ucontext uc;
+ unsigned long retcode;
+};
+
+static int
+restore_sigcontext(struct pt_regs *regs, struct sigcontext *sc)
+{
+ __get_user(regs->ARM_r0, &sc->arm_r0);
+ __get_user(regs->ARM_r1, &sc->arm_r1);
+ __get_user(regs->ARM_r2, &sc->arm_r2);
+ __get_user(regs->ARM_r3, &sc->arm_r3);
+ __get_user(regs->ARM_r4, &sc->arm_r4);
+ __get_user(regs->ARM_r5, &sc->arm_r5);
+ __get_user(regs->ARM_r6, &sc->arm_r6);
+ __get_user(regs->ARM_r7, &sc->arm_r7);
+ __get_user(regs->ARM_r8, &sc->arm_r8);
+ __get_user(regs->ARM_r9, &sc->arm_r9);
+ __get_user(regs->ARM_r10, &sc->arm_r10);
+ __get_user(regs->ARM_fp, &sc->arm_fp);
+ __get_user(regs->ARM_ip, &sc->arm_ip);
+ __get_user(regs->ARM_sp, &sc->arm_sp);
+ __get_user(regs->ARM_lr, &sc->arm_lr);
+ __get_user(regs->ARM_pc, &sc->arm_pc); /* security! */
+#if defined(CONFIG_CPU_ARM6) || defined(CONFIG_CPU_SA110)
+ __get_user(regs->ARM_cpsr, &sc->arm_cpsr); /* security! */
+#endif
+
+ /* send SIGTRAP if we're single-stepping */
+ if (ptrace_cancel_bpt (current))
+ send_sig (SIGTRAP, current, 1);
+
+ return regs->ARM_r0;
+}
+
+asmlinkage int sys_sigreturn(struct pt_regs *regs)
+{
+ struct sigframe *frame;
+ sigset_t set;
+
+ frame = (struct sigframe *)regs->ARM_sp;
+
+ if (verify_area(VERIFY_READ, frame, sizeof (*frame)))
+ goto badframe;
+ if (__get_user(set.sig[0], &frame->sc.oldmask)
+ || (_NSIG_WORDS > 1
+ && __copy_from_user(&set.sig[1], &frame->extramask,
+ sizeof(frame->extramask))))
+ goto badframe;
+
+ sigdelsetmask(&set, ~_BLOCKABLE);
+ spin_lock_irq(&current->sigmask_lock);
+ current->blocked = set;
+ recalc_sigpending(current);
+ spin_unlock_irq(&current->sigmask_lock);
+
+ return restore_sigcontext(regs, &frame->sc);
+
+badframe:
+ lock_kernel();
+ do_exit(SIGSEGV);
+}
+
+asmlinkage int sys_rt_sigreturn(struct pt_regs *regs)
+{
+ struct rt_sigframe *frame;
+ sigset_t set;
+
+ frame = (struct rt_sigframe *)regs->ARM_sp;
+
+ if (verify_area(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->sigmask_lock);
+ current->blocked = set;
+ recalc_sigpending(current);
+ spin_unlock_irq(&current->sigmask_lock);
+
+ return restore_sigcontext(regs, &frame->uc.uc_mcontext);
+
+badframe:
+ lock_kernel();
+ do_exit(SIGSEGV);
+}
+
+static void
+setup_sigcontext(struct sigcontext *sc, /*struct _fpstate *fpstate,*/
+ struct pt_regs *regs, unsigned long mask)
+{
+ __put_user (regs->ARM_r0, &sc->arm_r0);
+ __put_user (regs->ARM_r1, &sc->arm_r1);
+ __put_user (regs->ARM_r2, &sc->arm_r2);
+ __put_user (regs->ARM_r3, &sc->arm_r3);
+ __put_user (regs->ARM_r4, &sc->arm_r4);
+ __put_user (regs->ARM_r5, &sc->arm_r5);
+ __put_user (regs->ARM_r6, &sc->arm_r6);
+ __put_user (regs->ARM_r7, &sc->arm_r7);
+ __put_user (regs->ARM_r8, &sc->arm_r8);
+ __put_user (regs->ARM_r9, &sc->arm_r9);
+ __put_user (regs->ARM_r10, &sc->arm_r10);
+ __put_user (regs->ARM_fp, &sc->arm_fp);
+ __put_user (regs->ARM_ip, &sc->arm_ip);
+ __put_user (regs->ARM_sp, &sc->arm_sp);
+ __put_user (regs->ARM_lr, &sc->arm_lr);
+ __put_user (regs->ARM_pc, &sc->arm_pc); /* security! */
+#if defined(CONFIG_CPU_ARM6) || defined(CONFIG_CPU_SA110)
+ __put_user (regs->ARM_cpsr, &sc->arm_cpsr); /* security! */
+#endif
+
+ __put_user (current->tss.trap_no, &sc->trap_no);
+ __put_user (current->tss.error_code, &sc->error_code);
+ __put_user (mask, &sc->oldmask);
+}
+
+static void setup_frame(int sig, struct k_sigaction *ka,
+ sigset_t *set, struct pt_regs *regs)
+{
+ struct sigframe *frame;
+ unsigned long retcode;
+
+ frame = (struct sigframe *)regs->ARM_sp - 1;
+
+ if (!access_ok(VERIFT_WRITE, frame, sizeof (*frame)))
+ goto segv_and_exit;
+
+ setup_sigcontext(&frame->sc, /*&frame->fpstate,*/ regs, set->sig[0]);
+
+ if (_NSIG_WORDS > 1) {
+ __copy_to_user(frame->extramask, &set->sig[1],
+ sizeof(frame->extramask));
+ }
+
+ /* Set up to return from userspace. If provided, use a stub
+ already in userspace. */
+ if (ka->sa.sa_flags & SA_RESTORER) {
+ retcode = (unsigned long)ka->sa.sa_restorer; /* security! */
+ } else {
+ retcode = (unsigned long)&frame->retcode;
+ __put_user(SWI_SYS_SIGRETURN, &frame->retcode);
+ __flush_entry_to_ram (&frame->retcode);
+ }
+
+ if (current->exec_domain && current->exec_domain->signal_invmap && sig < 32)
+ regs->ARM_r0 = current->exec_domain->signal_invmap[sig];
+ else
+ regs->ARM_r0 = sig;
+ regs->ARM_sp = (unsigned long)frame;
+ regs->ARM_lr = retcode;
+ regs->ARM_pc = (unsigned long)ka->sa.sa_handler; /* security! */
+ return;
+
+segv_and_exit:
+ lock_kernel();
+ do_exit (SIGSEGV);
+}
+
+static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
+ sigset_t *set, struct pt_regs *regs)
+{
+ struct rt_sigframe *frame;
+ unsigned long retcode;
+
+ frame = (struct rt_sigframe *)regs->ARM_sp - 1;
+ if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
+ goto segv_and_exit;
+
+ __put_user(&frame->info, &frame->pinfo);
+ __put_user(&frame->uc, &frame->puc);
+ __copy_to_user(&frame->info, info, sizeof(*info));
+
+ /* Clear all the bits of the ucontext we don't use. */
+ __clear_user(&frame->uc, offsetof(struct ucontext, uc_mcontext));
+
+ setup_sigcontext(&frame->uc.uc_mcontext, /*&frame->fpstate,*/
+ regs, set->sig[0]);
+ __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+
+ /* Set up to return from userspace. If provided, use a stub
+ already in userspace. */
+ if (ka->sa.sa_flags & SA_RESTORER) {
+ retcode = (unsigned long)ka->sa.sa_restorer; /* security! */
+ } else {
+ retcode = (unsigned long)&frame->retcode;
+ __put_user(SWI_SYS_RT_SIGRETURN, &frame->retcode);
+ __flush_entry_to_ram (&frame->retcode);
+ }
+
+ if (current->exec_domain && current->exec_domain->signal_invmap && sig < 32)
+ regs->ARM_r0 = current->exec_domain->signal_invmap[sig];
+ else
+ regs->ARM_r0 = sig;
+ regs->ARM_sp = (unsigned long)frame;
+ regs->ARM_lr = retcode;
+ regs->ARM_pc = (unsigned long)ka->sa.sa_handler; /* security! */
+ return;
+
+segv_and_exit:
+ lock_kernel();
+ do_exit (SIGSEGV);
+}
+
+/*
+ * OK, we're invoking a handler
+ */
+static void
+handle_signal(unsigned long sig, struct k_sigaction *ka,
+ siginfo_t *info, sigset_t *oldset, struct pt_regs * regs)
+{
+ /* 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_ONESHOT)
+ ka->sa.sa_handler = SIG_DFL;
+
+ if (!(ka->sa.sa_flags & SA_NODEFER)) {
+ spin_lock_irq(&current->sigmask_lock);
+ sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+ sigaddset(&current->blocked,sig);
+ recalc_sigpending(current);
+ spin_unlock_irq(&current->sigmask_lock);
+ }
+}
+
+/*
+ * 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.
+ *
+ * Note that we go through the signals twice: once to check the signals that
+ * the kernel can handle, and then we build all the user-level signal handling
+ * stack-frames in one go after that.
+ */
+asmlinkage int do_signal(sigset_t *oldset, struct pt_regs *regs)
+{
+ unsigned long instr, *pc = (unsigned long *)(instruction_pointer(regs)-4);
+ struct k_sigaction *ka;
+ siginfo_t info;
+ int single_stepping, swi_instr;
+
+ if (!oldset)
+ oldset = &current->blocked;
+
+ single_stepping = ptrace_cancel_bpt (current);
+ swi_instr = (!get_user (instr, pc) && (instr & 0x0f000000) == 0x0f000000);
+
+ for (;;) {
+ unsigned long signr;
+
+ spin_lock_irq (&current->sigmask_lock);
+ signr = dequeue_signal(&current->blocked, &info);
+ spin_unlock_irq (&current->sigmask_lock);
+
+ if (!signr)
+ break;
+
+ if ((current->flags & PF_PTRACED) && signr != SIGKILL) {
+ /* Let the debugger run. */
+ current->exit_code = signr;
+ current->state = TASK_STOPPED;
+ notify_parent(current, SIGCHLD);
+ schedule();
+ single_stepping |= ptrace_cancel_bpt (current);
+
+ /* We're back. Did the debugger cancel the sig? */
+ if (!(signr = current->exit_code))
+ continue;
+ current->exit_code = 0;
+
+ /* The debugger continued. Ignore SIGSTOP. */
+ if (signr == SIGSTOP)
+ continue;
+
+ /* Update the siginfo structure. Is this good? */
+ if (signr != info.si_signo) {
+ info.si_signo = signr;
+ info.si_errno = 0;
+ info.si_code = SI_USER;
+ info.si_pid = current->p_pptr->pid;
+ info.si_uid = current->p_pptr->uid;
+ }
+
+ /* If the (new) signal is now blocked, requeue it. */
+ if (sigismember(&current->blocked, signr)) {
+ send_sig_info(signr, &info, current);
+ continue;
+ }
+ }
+
+ ka = &current->sig->action[signr-1];
+ if (ka->sa.sa_handler == SIG_IGN) {
+ if (signr != SIGCHLD)
+ continue;
+ /* Check for SIGCHLD: it's special. */
+ while (sys_wait4(-1, NULL, WNOHANG, NULL) > 0)
+ /* nothing */;
+ continue;
+ }
+
+ if (ka->sa.sa_handler == SIG_DFL) {
+ int exit_code = signr;
+
+ /* Init gets no signals it doesn't want. */
+ if (current->pid == 1)
+ continue;
+
+ switch (signr) {
+ case SIGCONT: case SIGCHLD: case SIGWINCH:
+ continue;
+
+ case SIGTSTP: case SIGTTIN: case SIGTTOU:
+ if (is_orphaned_pgrp(current->pgrp))
+ continue;
+ /* FALLTHRU */
+
+ case SIGSTOP:
+ current->state = TASK_STOPPED;
+ current->exit_code = signr;
+ if (!(current->p_pptr->sig->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDSTOP))
+ notify_parent(current, SIGCHLD);
+ schedule();
+ continue;
+
+ case SIGQUIT: case SIGILL: case SIGTRAP:
+ case SIGABRT: case SIGFPE: case SIGSEGV:
+ lock_kernel();
+ if (current->binfmt
+ && current->binfmt->core_dump
+ && current->binfmt->core_dump(signr, regs))
+ exit_code |= 0x80;
+ unlock_kernel();
+ /* FALLTHRU */
+
+ default:
+ lock_kernel();
+ sigaddset(&current->signal, signr);
+ current->flags |= PF_SIGNALED;
+ do_exit(exit_code);
+ /* NOTREACHED */
+ }
+ }
+
+ /* Are we from a system call? */
+ if (swi_instr) {
+ switch (regs->ARM_r0) {
+ case -ERESTARTNOHAND:
+ regs->ARM_r0 = -EINTR;
+ break;
+
+ case -ERESTARTSYS:
+ if (!(ka->sa.sa_flags & SA_RESTART)) {
+ regs->ARM_r0 = -EINTR;
+ break;
+ }
+ /* fallthrough */
+ case -ERESTARTNOINTR:
+ regs->ARM_r0 = regs->ARM_ORIG_r0;
+ regs->ARM_pc -= 4;
+ }
+ }
+ /* Whee! Actually deliver the signal. */
+ handle_signal(signr, ka, &info, oldset, regs);
+ if (single_stepping)
+ ptrace_set_bpt (current);
+ return 1;
+ }
+
+ if (swi_instr &&
+ (regs->ARM_r0 == -ERESTARTNOHAND ||
+ regs->ARM_r0 == -ERESTARTSYS ||
+ regs->ARM_r0 == -ERESTARTNOINTR)) {
+ regs->ARM_r0 = regs->ARM_ORIG_r0;
+ regs->ARM_pc -= 4;
+ }
+ if (single_stepping)
+ ptrace_set_bpt (current);
+ return 0;
+}