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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/arm26/kernel/signal.c
downloadconfigs-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/arm26/kernel/signal.c')
-rw-r--r--arch/arm26/kernel/signal.c540
1 files changed, 540 insertions, 0 deletions
diff --git a/arch/arm26/kernel/signal.c b/arch/arm26/kernel/signal.c
new file mode 100644
index 00000000000..356d9809cc0
--- /dev/null
+++ b/arch/arm26/kernel/signal.c
@@ -0,0 +1,540 @@
+/*
+ * linux/arch/arm26/kernel/signal.c
+ *
+ * Copyright (C) 1995-2002 Russell King
+ * Copyright (C) 2003 Ian Molton (ARM26)
+ *
+ * FIXME!!! This is probably very broken (13/05/2003)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/config.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/signal.h>
+#include <linux/wait.h>
+#include <linux/ptrace.h>
+#include <linux/personality.h>
+#include <linux/tty.h>
+#include <linux/binfmts.h>
+#include <linux/elf.h>
+
+#include <asm/pgalloc.h>
+#include <asm/ucontext.h>
+#include <asm/uaccess.h>
+#include <asm/unistd.h>
+
+#include "ptrace.h"
+
+#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
+
+/*
+ * For ARM syscalls, we encode the syscall number into the instruction.
+ */
+#define SWI_SYS_SIGRETURN (0xef000000|(__NR_sigreturn))
+#define SWI_SYS_RT_SIGRETURN (0xef000000|(__NR_rt_sigreturn))
+
+static int do_signal(sigset_t *oldset, struct pt_regs * regs, int syscall);
+
+/*
+ * 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->sighand->siglock);
+ saveset = current->blocked;
+ siginitset(&current->blocked, mask);
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+ regs->ARM_r0 = -EINTR;
+
+ while (1) {
+ current->state = TASK_INTERRUPTIBLE;
+ schedule();
+ if (do_signal(&saveset, regs, 0))
+ 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->sighand->siglock);
+ saveset = current->blocked;
+ current->blocked = newset;
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+ regs->ARM_r0 = -EINTR;
+
+ while (1) {
+ current->state = TASK_INTERRUPTIBLE;
+ schedule();
+ if (do_signal(&saveset, regs, 0))
+ 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 (!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;
+}
+
+/*
+ * 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)
+{
+ int err = 0;
+
+ __get_user_error(regs->ARM_r0, &sc->arm_r0, err);
+ __get_user_error(regs->ARM_r1, &sc->arm_r1, err);
+ __get_user_error(regs->ARM_r2, &sc->arm_r2, err);
+ __get_user_error(regs->ARM_r3, &sc->arm_r3, err);
+ __get_user_error(regs->ARM_r4, &sc->arm_r4, err);
+ __get_user_error(regs->ARM_r5, &sc->arm_r5, err);
+ __get_user_error(regs->ARM_r6, &sc->arm_r6, err);
+ __get_user_error(regs->ARM_r7, &sc->arm_r7, err);
+ __get_user_error(regs->ARM_r8, &sc->arm_r8, err);
+ __get_user_error(regs->ARM_r9, &sc->arm_r9, err);
+ __get_user_error(regs->ARM_r10, &sc->arm_r10, err);
+ __get_user_error(regs->ARM_fp, &sc->arm_fp, err);
+ __get_user_error(regs->ARM_ip, &sc->arm_ip, err);
+ __get_user_error(regs->ARM_sp, &sc->arm_sp, err);
+ __get_user_error(regs->ARM_lr, &sc->arm_lr, err);
+ __get_user_error(regs->ARM_pc, &sc->arm_pc, err);
+
+ err |= !valid_user_regs(regs);
+
+ return err;
+}
+
+asmlinkage int sys_sigreturn(struct pt_regs *regs)
+{
+ struct sigframe *frame;
+ sigset_t set;
+
+ /*
+ * Since we stacked the signal on a 64-bit boundary,
+ * then 'sp' should be word aligned here. If it's
+ * not, then the user is trying to mess with us.
+ */
+ if (regs->ARM_sp & 7)
+ goto badframe;
+
+ frame = (struct sigframe *)regs->ARM_sp;
+
+ if (!access_ok(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->sighand->siglock);
+ current->blocked = set;
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+
+ if (restore_sigcontext(regs, &frame->sc))
+ goto badframe;
+
+ /* Send SIGTRAP if we're single-stepping */
+ if (current->ptrace & PT_SINGLESTEP) {
+ ptrace_cancel_bpt(current);
+ send_sig(SIGTRAP, current, 1);
+ }
+
+ return regs->ARM_r0;
+
+badframe:
+ force_sig(SIGSEGV, current);
+ return 0;
+}
+
+asmlinkage int sys_rt_sigreturn(struct pt_regs *regs)
+{
+ struct rt_sigframe *frame;
+ sigset_t set;
+
+ /*
+ * Since we stacked the signal on a 64-bit boundary,
+ * then 'sp' should be word aligned here. If it's
+ * not, then the user is trying to mess with us.
+ */
+ if (regs->ARM_sp & 7)
+ goto badframe;
+
+ frame = (struct rt_sigframe *)regs->ARM_sp;
+
+ 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(regs, &frame->uc.uc_mcontext))
+ goto badframe;
+
+ /* Send SIGTRAP if we're single-stepping */
+ if (current->ptrace & PT_SINGLESTEP) {
+ ptrace_cancel_bpt(current);
+ send_sig(SIGTRAP, current, 1);
+ }
+
+ return regs->ARM_r0;
+
+badframe:
+ force_sig(SIGSEGV, current);
+ return 0;
+}
+
+static int
+setup_sigcontext(struct sigcontext *sc, /*struct _fpstate *fpstate,*/
+ struct pt_regs *regs, unsigned long mask)
+{
+ int err = 0;
+
+ __put_user_error(regs->ARM_r0, &sc->arm_r0, err);
+ __put_user_error(regs->ARM_r1, &sc->arm_r1, err);
+ __put_user_error(regs->ARM_r2, &sc->arm_r2, err);
+ __put_user_error(regs->ARM_r3, &sc->arm_r3, err);
+ __put_user_error(regs->ARM_r4, &sc->arm_r4, err);
+ __put_user_error(regs->ARM_r5, &sc->arm_r5, err);
+ __put_user_error(regs->ARM_r6, &sc->arm_r6, err);
+ __put_user_error(regs->ARM_r7, &sc->arm_r7, err);
+ __put_user_error(regs->ARM_r8, &sc->arm_r8, err);
+ __put_user_error(regs->ARM_r9, &sc->arm_r9, err);
+ __put_user_error(regs->ARM_r10, &sc->arm_r10, err);
+ __put_user_error(regs->ARM_fp, &sc->arm_fp, err);
+ __put_user_error(regs->ARM_ip, &sc->arm_ip, err);
+ __put_user_error(regs->ARM_sp, &sc->arm_sp, err);
+ __put_user_error(regs->ARM_lr, &sc->arm_lr, err);
+ __put_user_error(regs->ARM_pc, &sc->arm_pc, err);
+
+ __put_user_error(current->thread.trap_no, &sc->trap_no, err);
+ __put_user_error(current->thread.error_code, &sc->error_code, err);
+ __put_user_error(current->thread.address, &sc->fault_address, err);
+ __put_user_error(mask, &sc->oldmask, err);
+
+ return err;
+}
+
+static inline void *
+get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, int framesize)
+{
+ unsigned long sp = regs->ARM_sp;
+
+ /*
+ * This is the X/Open sanctioned signal stack switching.
+ */
+ if ((ka->sa.sa_flags & SA_ONSTACK) && !sas_ss_flags(sp))
+ sp = current->sas_ss_sp + current->sas_ss_size;
+
+ /*
+ * ATPCS B01 mandates 8-byte alignment
+ */
+ return (void *)((sp - framesize) & ~7);
+}
+
+static int
+setup_return(struct pt_regs *regs, struct k_sigaction *ka,
+ unsigned long *rc, void *frame, int usig)
+{
+ unsigned long handler = (unsigned long)ka->sa.sa_handler;
+ unsigned long retcode;
+
+ if (ka->sa.sa_flags & SA_RESTORER) {
+ retcode = (unsigned long)ka->sa.sa_restorer;
+ } else {
+
+ if (__put_user((ka->sa.sa_flags & SA_SIGINFO)?SWI_SYS_RT_SIGRETURN:SWI_SYS_SIGRETURN, rc))
+ return 1;
+
+ retcode = ((unsigned long)rc);
+ }
+
+ regs->ARM_r0 = usig;
+ regs->ARM_sp = (unsigned long)frame;
+ regs->ARM_lr = retcode;
+ regs->ARM_pc = handler & ~3;
+
+ return 0;
+}
+
+static int
+setup_frame(int usig, struct k_sigaction *ka, sigset_t *set, struct pt_regs *regs)
+{
+ struct sigframe *frame = get_sigframe(ka, regs, sizeof(*frame));
+ int err = 0;
+
+ if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
+ return 1;
+
+ err |= setup_sigcontext(&frame->sc, /*&frame->fpstate,*/ regs, set->sig[0]);
+
+ if (_NSIG_WORDS > 1) {
+ err |= __copy_to_user(frame->extramask, &set->sig[1],
+ sizeof(frame->extramask));
+ }
+
+ if (err == 0)
+ err = setup_return(regs, ka, &frame->retcode, frame, usig);
+
+ return err;
+}
+
+static int
+setup_rt_frame(int usig, struct k_sigaction *ka, siginfo_t *info,
+ sigset_t *set, struct pt_regs *regs)
+{
+ struct rt_sigframe *frame = get_sigframe(ka, regs, sizeof(*frame));
+ int err = 0;
+
+ if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
+ return 1;
+
+ __put_user_error(&frame->info, &frame->pinfo, err);
+ __put_user_error(&frame->uc, &frame->puc, err);
+ err |= copy_siginfo_to_user(&frame->info, info);
+
+ /* Clear all the bits of the ucontext we don't use. */
+ err |= __clear_user(&frame->uc, offsetof(struct ucontext, uc_mcontext));
+
+ err |= setup_sigcontext(&frame->uc.uc_mcontext, /*&frame->fpstate,*/
+ regs, set->sig[0]);
+ err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+
+ if (err == 0)
+ err = setup_return(regs, ka, &frame->retcode, frame, usig);
+
+ if (err == 0) {
+ /*
+ * For realtime signals we must also set the second and third
+ * arguments for the signal handler.
+ * -- Peter Maydell <pmaydell@chiark.greenend.org.uk> 2000-12-06
+ */
+ regs->ARM_r1 = (unsigned long)frame->pinfo;
+ regs->ARM_r2 = (unsigned long)frame->puc;
+ }
+
+ return err;
+}
+
+static inline void restart_syscall(struct pt_regs *regs)
+{
+ regs->ARM_r0 = regs->ARM_ORIG_r0;
+ regs->ARM_pc -= 4;
+}
+
+/*
+ * OK, we're invoking a handler
+ */
+static void
+handle_signal(unsigned long sig, siginfo_t *info, sigset_t *oldset,
+ struct pt_regs * regs, int syscall)
+{
+ struct thread_info *thread = current_thread_info();
+ struct task_struct *tsk = current;
+ struct k_sigaction *ka = &tsk->sighand->action[sig-1];
+ int usig = sig;
+ int ret;
+
+ /*
+ * If we were from a system call, check for system call restarting...
+ */
+ if (syscall) {
+ switch (regs->ARM_r0) {
+ case -ERESTART_RESTARTBLOCK:
+ current_thread_info()->restart_block.fn =
+ do_no_restart_syscall;
+ case -ERESTARTNOHAND:
+ regs->ARM_r0 = -EINTR;
+ break;
+ case -ERESTARTSYS:
+ if (!(ka->sa.sa_flags & SA_RESTART)) {
+ regs->ARM_r0 = -EINTR;
+ break;
+ }
+ /* fallthrough */
+ case -ERESTARTNOINTR:
+ restart_syscall(regs);
+ }
+ }
+
+ /*
+ * translate the signal
+ */
+ if (usig < 32 && thread->exec_domain && thread->exec_domain->signal_invmap)
+ usig = thread->exec_domain->signal_invmap[usig];
+
+ /*
+ * Set up the stack frame
+ */
+ if (ka->sa.sa_flags & SA_SIGINFO)
+ ret = setup_rt_frame(usig, ka, info, oldset, regs);
+ else
+ ret = setup_frame(usig, ka, oldset, regs);
+
+ /*
+ * Check that the resulting registers are actually sane.
+ */
+ ret |= !valid_user_regs(regs);
+
+ if (ret == 0) {
+ if (ka->sa.sa_flags & SA_ONESHOT)
+ ka->sa.sa_handler = SIG_DFL;
+
+ if (!(ka->sa.sa_flags & SA_NODEFER)) {
+ spin_lock_irq(&tsk->sighand->siglock);
+ sigorsets(&tsk->blocked, &tsk->blocked,
+ &ka->sa.sa_mask);
+ sigaddset(&tsk->blocked, sig);
+ recalc_sigpending();
+ spin_unlock_irq(&tsk->sighand->siglock);
+ }
+ return;
+ }
+
+ force_sigsegv(sig, tsk);
+}
+
+/*
+ * 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.
+ */
+static int do_signal(sigset_t *oldset, struct pt_regs *regs, int syscall)
+{
+ 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 0;
+
+ if (current->ptrace & PT_SINGLESTEP)
+ ptrace_cancel_bpt(current);
+
+ signr = get_signal_to_deliver(&info, regs, NULL);
+ if (signr > 0) {
+ handle_signal(signr, &info, oldset, regs, syscall);
+ if (current->ptrace & PT_SINGLESTEP)
+ ptrace_set_bpt(current);
+ return 1;
+ }
+
+ /*
+ * No signal to deliver to the process - restart the syscall.
+ */
+ if (syscall) {
+ if (regs->ARM_r0 == -ERESTART_RESTARTBLOCK) {
+ u32 *usp;
+
+ regs->ARM_sp -= 12;
+ usp = (u32 *)regs->ARM_sp;
+
+ put_user(regs->ARM_pc, &usp[0]);
+ /* swi __NR_restart_syscall */
+ put_user(0xef000000 | __NR_restart_syscall, &usp[1]);
+ /* ldr pc, [sp], #12 */
+// FIXME!!! is #12 correct there?
+ put_user(0xe49df00c, &usp[2]);
+
+ regs->ARM_pc = regs->ARM_sp + 4;
+ }
+ if (regs->ARM_r0 == -ERESTARTNOHAND ||
+ regs->ARM_r0 == -ERESTARTSYS ||
+ regs->ARM_r0 == -ERESTARTNOINTR) {
+ restart_syscall(regs);
+ }
+ }
+ if (current->ptrace & PT_SINGLESTEP)
+ ptrace_set_bpt(current);
+ return 0;
+}
+
+asmlinkage void
+do_notify_resume(struct pt_regs *regs, unsigned int thread_flags, int syscall)
+{
+ if (thread_flags & _TIF_SIGPENDING)
+ do_signal(&current->blocked, regs, syscall);
+}