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-rw-r--r--arch/sh/kernel/signal.c607
1 files changed, 607 insertions, 0 deletions
diff --git a/arch/sh/kernel/signal.c b/arch/sh/kernel/signal.c
new file mode 100644
index 000000000000..06f1b47eded9
--- /dev/null
+++ b/arch/sh/kernel/signal.c
@@ -0,0 +1,607 @@
+/*
+ * linux/arch/sh/kernel/signal.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
+ *
+ * SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
+ *
+ */
+
+#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 <linux/tty.h>
+#include <linux/personality.h>
+#include <linux/binfmts.h>
+
+#include <asm/ucontext.h>
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/cacheflush.h>
+
+#define DEBUG_SIG 0
+
+#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
+
+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(old_sigset_t mask,
+ unsigned long r5, unsigned long r6, unsigned long r7,
+ 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.regs[0] = -EINTR;
+ while (1) {
+ current->state = TASK_INTERRUPTIBLE;
+ schedule();
+ if (do_signal(&regs, &saveset))
+ return -EINTR;
+ }
+}
+
+asmlinkage int
+sys_rt_sigsuspend(sigset_t *unewset, size_t sigsetsize,
+ unsigned long r6, unsigned long r7,
+ 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.regs[0] = -EINTR;
+ while (1) {
+ current->state = TASK_INTERRUPTIBLE;
+ schedule();
+ if (do_signal(&regs, &saveset))
+ return -EINTR;
+ }
+}
+
+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,
+ unsigned long r6, unsigned long r7,
+ struct pt_regs regs)
+{
+ return do_sigaltstack(uss, uoss, regs.regs[15]);
+}
+
+
+/*
+ * Do a signal return; undo the signal stack.
+ */
+
+#define MOVW(n) (0x9300|((n)-2)) /* Move mem word at PC+n to R3 */
+#define TRAP16 0xc310 /* Syscall w/no args (NR in R3) */
+#define OR_R0_R0 0x200b /* or r0,r0 (insert to avoid hardware bug) */
+
+struct sigframe
+{
+ struct sigcontext sc;
+ unsigned long extramask[_NSIG_WORDS-1];
+ u16 retcode[8];
+};
+
+struct rt_sigframe
+{
+ struct siginfo info;
+ struct ucontext uc;
+ u16 retcode[8];
+};
+
+#ifdef CONFIG_SH_FPU
+static inline int restore_sigcontext_fpu(struct sigcontext __user *sc)
+{
+ struct task_struct *tsk = current;
+
+ if (!(cpu_data->flags & CPU_HAS_FPU))
+ return 0;
+
+ set_used_math();
+ return __copy_from_user(&tsk->thread.fpu.hard, &sc->sc_fpregs[0],
+ sizeof(long)*(16*2+2));
+}
+
+static inline int save_sigcontext_fpu(struct sigcontext __user *sc,
+ struct pt_regs *regs)
+{
+ struct task_struct *tsk = current;
+
+ if (!(cpu_data->flags & CPU_HAS_FPU))
+ return 0;
+
+ if (!used_math()) {
+ __put_user(0, &sc->sc_ownedfp);
+ return 0;
+ }
+
+ __put_user(1, &sc->sc_ownedfp);
+
+ /* This will cause a "finit" to be triggered by the next
+ attempted FPU operation by the 'current' process.
+ */
+ clear_used_math();
+
+ unlazy_fpu(tsk, regs);
+ return __copy_to_user(&sc->sc_fpregs[0], &tsk->thread.fpu.hard,
+ sizeof(long)*(16*2+2));
+}
+#endif /* CONFIG_SH_FPU */
+
+static int
+restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *r0_p)
+{
+ unsigned int err = 0;
+
+#define COPY(x) err |= __get_user(regs->x, &sc->sc_##x)
+ COPY(regs[1]);
+ COPY(regs[2]); COPY(regs[3]);
+ COPY(regs[4]); COPY(regs[5]);
+ COPY(regs[6]); COPY(regs[7]);
+ COPY(regs[8]); COPY(regs[9]);
+ COPY(regs[10]); COPY(regs[11]);
+ COPY(regs[12]); COPY(regs[13]);
+ COPY(regs[14]); COPY(regs[15]);
+ COPY(gbr); COPY(mach);
+ COPY(macl); COPY(pr);
+ COPY(sr); COPY(pc);
+#undef COPY
+
+#ifdef CONFIG_SH_FPU
+ if (cpu_data->flags & CPU_HAS_FPU) {
+ int owned_fp;
+ struct task_struct *tsk = current;
+
+ regs->sr |= SR_FD; /* Release FPU */
+ clear_fpu(tsk, regs);
+ clear_used_math();
+ __get_user (owned_fp, &sc->sc_ownedfp);
+ if (owned_fp)
+ err |= restore_sigcontext_fpu(sc);
+ }
+#endif
+
+ regs->tra = -1; /* disable syscall checks */
+ err |= __get_user(*r0_p, &sc->sc_regs[0]);
+ return err;
+}
+
+asmlinkage int sys_sigreturn(unsigned long r4, unsigned long r5,
+ unsigned long r6, unsigned long r7,
+ struct pt_regs regs)
+{
+ struct sigframe __user *frame = (struct sigframe __user *)regs.regs[15];
+ sigset_t set;
+ int r0;
+
+ 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, &r0))
+ goto badframe;
+ return r0;
+
+badframe:
+ force_sig(SIGSEGV, current);
+ return 0;
+}
+
+asmlinkage int sys_rt_sigreturn(unsigned long r4, unsigned long r5,
+ unsigned long r6, unsigned long r7,
+ struct pt_regs regs)
+{
+ struct rt_sigframe __user *frame = (struct rt_sigframe __user *)regs.regs[15];
+ sigset_t set;
+ stack_t st;
+ int r0;
+
+ 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, &r0))
+ goto badframe;
+
+ if (__copy_from_user(&st, &frame->uc.uc_stack, sizeof(st)))
+ goto badframe;
+ /* It is more difficult to avoid calling this function than to
+ call it and ignore errors. */
+ do_sigaltstack(&st, NULL, regs.regs[15]);
+
+ return r0;
+
+badframe:
+ force_sig(SIGSEGV, current);
+ return 0;
+}
+
+/*
+ * Set up a signal frame.
+ */
+
+static int
+setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
+ unsigned long mask)
+{
+ int err = 0;
+
+#define COPY(x) err |= __put_user(regs->x, &sc->sc_##x)
+ COPY(regs[0]); COPY(regs[1]);
+ COPY(regs[2]); COPY(regs[3]);
+ COPY(regs[4]); COPY(regs[5]);
+ COPY(regs[6]); COPY(regs[7]);
+ COPY(regs[8]); COPY(regs[9]);
+ COPY(regs[10]); COPY(regs[11]);
+ COPY(regs[12]); COPY(regs[13]);
+ COPY(regs[14]); COPY(regs[15]);
+ COPY(gbr); COPY(mach);
+ COPY(macl); COPY(pr);
+ COPY(sr); COPY(pc);
+#undef COPY
+
+#ifdef CONFIG_SH_FPU
+ err |= save_sigcontext_fpu(sc, regs);
+#endif
+
+ /* non-iBCS2 extensions.. */
+ err |= __put_user(mask, &sc->oldmask);
+
+ return err;
+}
+
+/*
+ * Determine which stack to use..
+ */
+static inline void __user *
+get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
+{
+ if (ka->sa.sa_flags & SA_ONSTACK) {
+ if (sas_ss_flags(sp) == 0)
+ sp = current->sas_ss_sp + current->sas_ss_size;
+ }
+
+ return (void __user *)((sp - frame_size) & -8ul);
+}
+
+static void setup_frame(int sig, struct k_sigaction *ka,
+ sigset_t *set, struct pt_regs *regs)
+{
+ struct sigframe __user *frame;
+ int err = 0;
+ int signal;
+
+ frame = get_sigframe(ka, regs->regs[15], sizeof(*frame));
+
+ if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+ goto give_sigsegv;
+
+ signal = current_thread_info()->exec_domain
+ && current_thread_info()->exec_domain->signal_invmap
+ && sig < 32
+ ? current_thread_info()->exec_domain->signal_invmap[sig]
+ : sig;
+
+ err |= setup_sigcontext(&frame->sc, regs, set->sig[0]);
+
+ if (_NSIG_WORDS > 1) {
+ err |= __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) {
+ regs->pr = (unsigned long) ka->sa.sa_restorer;
+ } else {
+ /* Generate return code (system call to sigreturn) */
+ err |= __put_user(MOVW(7), &frame->retcode[0]);
+ err |= __put_user(TRAP16, &frame->retcode[1]);
+ err |= __put_user(OR_R0_R0, &frame->retcode[2]);
+ err |= __put_user(OR_R0_R0, &frame->retcode[3]);
+ err |= __put_user(OR_R0_R0, &frame->retcode[4]);
+ err |= __put_user(OR_R0_R0, &frame->retcode[5]);
+ err |= __put_user(OR_R0_R0, &frame->retcode[6]);
+ err |= __put_user((__NR_sigreturn), &frame->retcode[7]);
+ regs->pr = (unsigned long) frame->retcode;
+ }
+
+ if (err)
+ goto give_sigsegv;
+
+ /* Set up registers for signal handler */
+ regs->regs[15] = (unsigned long) frame;
+ regs->regs[4] = signal; /* Arg for signal handler */
+ regs->regs[5] = 0;
+ regs->regs[6] = (unsigned long) &frame->sc;
+ regs->pc = (unsigned long) ka->sa.sa_handler;
+
+ set_fs(USER_DS);
+
+#if DEBUG_SIG
+ printk("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n",
+ current->comm, current->pid, frame, regs->pc, regs->pr);
+#endif
+
+ flush_cache_sigtramp(regs->pr);
+ if ((-regs->pr & (L1_CACHE_BYTES-1)) < sizeof(frame->retcode))
+ flush_cache_sigtramp(regs->pr + L1_CACHE_BYTES);
+ return;
+
+give_sigsegv:
+ force_sigsegv(sig, current);
+}
+
+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 err = 0;
+ int signal;
+
+ frame = get_sigframe(ka, regs->regs[15], sizeof(*frame));
+
+ if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+ goto give_sigsegv;
+
+ signal = current_thread_info()->exec_domain
+ && current_thread_info()->exec_domain->signal_invmap
+ && sig < 32
+ ? current_thread_info()->exec_domain->signal_invmap[sig]
+ : sig;
+
+ err |= copy_siginfo_to_user(&frame->info, info);
+
+ /* Create the ucontext. */
+ err |= __put_user(0, &frame->uc.uc_flags);
+ err |= __put_user(0, &frame->uc.uc_link);
+ err |= __put_user((void *)current->sas_ss_sp,
+ &frame->uc.uc_stack.ss_sp);
+ err |= __put_user(sas_ss_flags(regs->regs[15]),
+ &frame->uc.uc_stack.ss_flags);
+ err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
+ err |= setup_sigcontext(&frame->uc.uc_mcontext,
+ regs, set->sig[0]);
+ err |= __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) {
+ regs->pr = (unsigned long) ka->sa.sa_restorer;
+ } else {
+ /* Generate return code (system call to rt_sigreturn) */
+ err |= __put_user(MOVW(7), &frame->retcode[0]);
+ err |= __put_user(TRAP16, &frame->retcode[1]);
+ err |= __put_user(OR_R0_R0, &frame->retcode[2]);
+ err |= __put_user(OR_R0_R0, &frame->retcode[3]);
+ err |= __put_user(OR_R0_R0, &frame->retcode[4]);
+ err |= __put_user(OR_R0_R0, &frame->retcode[5]);
+ err |= __put_user(OR_R0_R0, &frame->retcode[6]);
+ err |= __put_user((__NR_rt_sigreturn), &frame->retcode[7]);
+ regs->pr = (unsigned long) frame->retcode;
+ }
+
+ if (err)
+ goto give_sigsegv;
+
+ /* Set up registers for signal handler */
+ regs->regs[15] = (unsigned long) frame;
+ regs->regs[4] = signal; /* Arg for signal handler */
+ regs->regs[5] = (unsigned long) &frame->info;
+ regs->regs[6] = (unsigned long) &frame->uc;
+ regs->pc = (unsigned long) ka->sa.sa_handler;
+
+ set_fs(USER_DS);
+
+#if DEBUG_SIG
+ printk("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n",
+ current->comm, current->pid, frame, regs->pc, regs->pr);
+#endif
+
+ flush_cache_sigtramp(regs->pr);
+ if ((-regs->pr & (L1_CACHE_BYTES-1)) < sizeof(frame->retcode))
+ flush_cache_sigtramp(regs->pr + L1_CACHE_BYTES);
+ return;
+
+give_sigsegv:
+ force_sigsegv(sig, current);
+}
+
+/*
+ * 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)
+{
+ /* Are we from a system call? */
+ if (regs->tra >= 0) {
+ /* If so, check system call restarting.. */
+ switch (regs->regs[0]) {
+ case -ERESTARTNOHAND:
+ regs->regs[0] = -EINTR;
+ break;
+
+ case -ERESTARTSYS:
+ if (!(ka->sa.sa_flags & SA_RESTART)) {
+ regs->regs[0] = -EINTR;
+ break;
+ }
+ /* fallthrough */
+ case -ERESTARTNOINTR:
+ regs->pc -= 2;
+ }
+ } else {
+ /* gUSA handling */
+#ifdef CONFIG_PREEMPT
+ unsigned long flags;
+
+ local_irq_save(flags);
+#endif
+ if (regs->regs[15] >= 0xc0000000) {
+ int offset = (int)regs->regs[15];
+
+ /* Reset stack pointer: clear critical region mark */
+ regs->regs[15] = regs->regs[1];
+ if (regs->pc < regs->regs[0])
+ /* Go to rewind point #1 */
+ regs->pc = regs->regs[0] + offset - 2;
+ }
+#ifdef CONFIG_PREEMPT
+ local_irq_restore(flags);
+#endif
+ }
+
+ /* 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->sighand->siglock);
+ sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+ sigaddset(&current->blocked,sig);
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+ }
+}
+
+/*
+ * 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.
+ */
+int do_signal(struct pt_regs *regs, sigset_t *oldset)
+{
+ siginfo_t info;
+ int signr;
+ struct k_sigaction ka;
+
+ /*
+ * 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 (try_to_freeze(0))
+ goto no_signal;
+
+ if (!oldset)
+ oldset = &current->blocked;
+
+ signr = get_signal_to_deliver(&info, &ka, regs, NULL);
+ if (signr > 0) {
+ /* Whee! Actually deliver the signal. */
+ handle_signal(signr, &ka, &info, oldset, regs);
+ return 1;
+ }
+
+ no_signal:
+ /* Did we come from a system call? */
+ if (regs->tra >= 0) {
+ /* Restart the system call - no handlers present */
+ if (regs->regs[0] == -ERESTARTNOHAND ||
+ regs->regs[0] == -ERESTARTSYS ||
+ regs->regs[0] == -ERESTARTNOINTR ||
+ regs->regs[0] == -ERESTART_RESTARTBLOCK) {
+ regs->pc -= 2;
+ }
+ }
+ return 0;
+}
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