]> rtime.felk.cvut.cz Git - mcf548x/linux.git/blobdiff - arch/m68k/coldfire/signal.c
Headers cleanup
[mcf548x/linux.git] / arch / m68k / coldfire / signal.c
diff --git a/arch/m68k/coldfire/signal.c b/arch/m68k/coldfire/signal.c
new file mode 100644 (file)
index 0000000..38671c4
--- /dev/null
@@ -0,0 +1,871 @@
+/*
+ *  linux/arch/m68k/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.
+ */
+
+/*
+ * Derived from m68k/kernel/signal.c and the original authors are credited
+ * there.
+ *
+ * Coldfire support by:
+ * Matt Waddel Matt.Waddel@freescale.com
+ * Copyright Freescale Semiconductor, Inc 2007
+ */
+
+#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 <asm/setup.h>
+#include <asm/cf_uaccess.h>
+#include <asm/cf_pgtable.h>
+#include <asm/traps.h>
+#include <asm/ucontext.h>
+#include <asm/cacheflush.h>
+
+#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
+
+asmlinkage int do_signal(sigset_t *oldset, struct pt_regs *regs);
+
+const int frame_extra_sizes[16] = {
+  [1]  = -1,
+  [2]  = sizeof(((struct frame *)0)->un.fmt2),
+  [3]  = sizeof(((struct frame *)0)->un.fmt3),
+  [4]  = 0,
+  [5]  = -1,
+  [6]  = -1,
+  [7]  = sizeof(((struct frame *)0)->un.fmt7),
+  [8]  = -1,
+  [9]  = sizeof(((struct frame *)0)->un.fmt9),
+  [10] = sizeof(((struct frame *)0)->un.fmta),
+  [11] = sizeof(((struct frame *)0)->un.fmtb),
+  [12] = -1,
+  [13] = -1,
+  [14] = -1,
+  [15] = -1,
+};
+
+/*
+ * Atomically swap in the new signal mask, and wait for a signal.
+ */
+asmlinkage int do_sigsuspend(struct pt_regs *regs)
+{
+       old_sigset_t mask = regs->d3;
+       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->d0 = -EINTR;
+       while (1) {
+               current->state = TASK_INTERRUPTIBLE;
+               schedule();
+               if (do_signal(&saveset, regs))
+                       return -EINTR;
+       }
+}
+
+asmlinkage int
+do_rt_sigsuspend(struct pt_regs *regs)
+{
+       sigset_t __user *unewset = (sigset_t __user *)regs->d1;
+       size_t sigsetsize = (size_t)regs->d2;
+       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->d0 = -EINTR;
+       while (1) {
+               current->state = TASK_INTERRUPTIBLE;
+               schedule();
+               if (do_signal(&saveset, regs))
+                       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)
+{
+       return do_sigaltstack(uss, uoss, rdusp());
+}
+
+
+/*
+ * 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 sigframe
+{
+       char __user *pretcode;
+       int sig;
+       int code;
+       struct sigcontext __user *psc;
+       char retcode[16];
+       unsigned long extramask[_NSIG_WORDS-1];
+       struct sigcontext sc;
+};
+
+struct rt_sigframe
+{
+       char __user *pretcode;
+       int sig;
+       struct siginfo __user *pinfo;
+       void __user *puc;
+       char retcode[16];
+       struct siginfo info;
+       struct ucontext uc;
+};
+
+#define FPCONTEXT_SIZE 216
+#define uc_fpstate     uc_filler[0]
+#define uc_formatvec   uc_filler[FPCONTEXT_SIZE/4]
+#define uc_extra       uc_filler[FPCONTEXT_SIZE/4+1]
+
+#ifdef CONFIG_FPU
+static unsigned char fpu_version; /* version num of fpu, set by setup_frame */
+
+static inline int restore_fpu_state(struct sigcontext *sc)
+{
+       int err = 1;
+
+       if (FPU_IS_EMU) {
+           /* restore registers */
+           memcpy(current->thread.fpcntl, sc->sc_fpcntl, 12);
+           memcpy(current->thread.fp, sc->sc_fpregs, 24);
+           return 0;
+       }
+
+       if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) {
+           /* Verify the frame format.  */
+           if (!CPU_IS_060 && (sc->sc_fpstate[0] != fpu_version))
+               goto out;
+           if (CPU_IS_020_OR_030) {
+               if (m68k_fputype & FPU_68881 &&
+                   !(sc->sc_fpstate[1] == 0x18 || sc->sc_fpstate[1] == 0xb4))
+                   goto out;
+               if (m68k_fputype & FPU_68882 &&
+                   !(sc->sc_fpstate[1] == 0x38 || sc->sc_fpstate[1] == 0xd4))
+                   goto out;
+           } else if (CPU_IS_040) {
+               if (!(sc->sc_fpstate[1] == 0x00 ||
+                     sc->sc_fpstate[1] == 0x28 ||
+                     sc->sc_fpstate[1] == 0x60))
+                   goto out;
+           } else if (CPU_IS_060) {
+               if (!(sc->sc_fpstate[3] == 0x00 ||
+                     sc->sc_fpstate[3] == 0x60 ||
+                     sc->sc_fpstate[3] == 0xe0))
+                   goto out;
+           } else
+               goto out;
+
+       }
+       err = 0;
+
+out:
+       return err;
+}
+
+static inline int rt_restore_fpu_state(struct ucontext __user *uc)
+{
+       unsigned char fpstate[FPCONTEXT_SIZE];
+       int context_size = CPU_IS_060 ? 8 : 0;
+       fpregset_t fpregs;
+       int err = 1;
+
+       if (FPU_IS_EMU) {
+               /* restore fpu control register */
+               if (__copy_from_user(current->thread.fpcntl,
+                               uc->uc_mcontext.fpregs.f_fpcntl, 12))
+                       goto out;
+               /* restore all other fpu register */
+               if (__copy_from_user(current->thread.fp,
+                               uc->uc_mcontext.fpregs.f_fpregs, 96))
+                       goto out;
+               return 0;
+       }
+
+       if (__get_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate))
+               goto out;
+       if (CPU_IS_060 ? fpstate[2] : fpstate[0]) {
+               if (!CPU_IS_060)
+                       context_size = fpstate[1];
+               /* Verify the frame format.  */
+               if (!CPU_IS_060 && (fpstate[0] != fpu_version))
+                       goto out;
+               if (CPU_IS_020_OR_030) {
+                       if (m68k_fputype & FPU_68881 &&
+                           !(context_size == 0x18 || context_size == 0xb4))
+                               goto out;
+                       if (m68k_fputype & FPU_68882 &&
+                           !(context_size == 0x38 || context_size == 0xd4))
+                               goto out;
+               } else if (CPU_IS_040) {
+                       if (!(context_size == 0x00 ||
+                             context_size == 0x28 ||
+                             context_size == 0x60))
+                               goto out;
+               } else if (CPU_IS_060) {
+                       if (!(fpstate[3] == 0x00 ||
+                             fpstate[3] == 0x60 ||
+                             fpstate[3] == 0xe0))
+                               goto out;
+               } else
+                       goto out;
+               if (__copy_from_user(&fpregs, &uc->uc_mcontext.fpregs,
+                                    sizeof(fpregs)))
+                       goto out;
+       }
+       if (context_size &&
+           __copy_from_user(fpstate + 4, (long __user *)&uc->uc_fpstate + 1,
+                            context_size))
+               goto out;
+       err = 0;
+
+out:
+       return err;
+}
+#endif
+
+static inline int
+restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *usc,
+       void __user *fp, int *pd0)
+{
+       int fsize, formatvec;
+       struct sigcontext context;
+       int err = 0;
+
+       /* get previous context */
+       if (copy_from_user(&context, usc, sizeof(context)))
+               goto badframe;
+
+       /* restore passed registers */
+       regs->d1 = context.sc_d1;
+       regs->a0 = context.sc_a0;
+       regs->a1 = context.sc_a1;
+       regs->sr = (regs->sr & 0xff00) | (context.sc_sr & 0xff);
+       regs->pc = context.sc_pc;
+       regs->orig_d0 = -1;             /* disable syscall checks */
+       wrusp(context.sc_usp);
+       formatvec = context.sc_formatvec;
+       regs->format = formatvec >> 12;
+       regs->vector = formatvec & 0xfff;
+
+#ifdef CONFIG_FPU
+       err = restore_fpu_state(&context);
+#endif
+
+       fsize = frame_extra_sizes[regs->format];
+       if (fsize < 0) {
+               /*
+                * user process trying to return with weird frame format
+                */
+#ifdef DEBUG
+               printk(KERN_DEBUG "user process returning with weird \
+                       frame format\n");
+#endif
+               goto badframe;
+       }
+
+       /* OK.  Make room on the supervisor stack for the extra junk,
+        * if necessary.
+        */
+
+       {
+               struct switch_stack *sw = (struct switch_stack *)regs - 1;
+               regs->d0 = context.sc_d0;
+#define frame_offset (sizeof(struct pt_regs)+sizeof(struct switch_stack))
+               __asm__ __volatile__
+                       ("   movel %0,%/sp\n\t"
+                        "   bra ret_from_signal\n"
+                        "4:\n"
+                        ".section __ex_table,\"a\"\n"
+                        "   .align 4\n"
+                        "   .long 2b,4b\n"
+                        ".previous"
+                        : /* no outputs, it doesn't ever return */
+                        : "a" (sw), "d" (fsize), "d" (frame_offset/4-1),
+                          "n" (frame_offset), "a" (fp)
+                        : "a0");
+#undef frame_offset
+               /*
+                * If we ever get here an exception occurred while
+                * building the above stack-frame.
+                */
+               goto badframe;
+       }
+
+       *pd0 = context.sc_d0;
+       return err;
+
+badframe:
+       return 1;
+}
+
+static inline int
+rt_restore_ucontext(struct pt_regs *regs, struct switch_stack *sw,
+                   struct ucontext __user *uc, int *pd0)
+{
+       int fsize, temp;
+       greg_t __user *gregs = uc->uc_mcontext.gregs;
+       unsigned long usp;
+       int err;
+
+       err = __get_user(temp, &uc->uc_mcontext.version);
+       if (temp != MCONTEXT_VERSION)
+               goto badframe;
+       /* restore passed registers */
+       err |= __get_user(regs->d0, &gregs[0]);
+       err |= __get_user(regs->d1, &gregs[1]);
+       err |= __get_user(regs->d2, &gregs[2]);
+       err |= __get_user(regs->d3, &gregs[3]);
+       err |= __get_user(regs->d4, &gregs[4]);
+       err |= __get_user(regs->d5, &gregs[5]);
+       err |= __get_user(sw->d6, &gregs[6]);
+       err |= __get_user(sw->d7, &gregs[7]);
+       err |= __get_user(regs->a0, &gregs[8]);
+       err |= __get_user(regs->a1, &gregs[9]);
+       err |= __get_user(regs->a2, &gregs[10]);
+       err |= __get_user(sw->a3, &gregs[11]);
+       err |= __get_user(sw->a4, &gregs[12]);
+       err |= __get_user(sw->a5, &gregs[13]);
+       err |= __get_user(sw->a6, &gregs[14]);
+       err |= __get_user(usp, &gregs[15]);
+       wrusp(usp);
+       err |= __get_user(regs->pc, &gregs[16]);
+       err |= __get_user(temp, &gregs[17]);
+       regs->sr = (regs->sr & 0xff00) | (temp & 0xff);
+       regs->orig_d0 = -1;             /* disable syscall checks */
+       err |= __get_user(temp, &uc->uc_formatvec);
+       regs->format = temp >> 12;
+       regs->vector = temp & 0xfff;
+
+#ifdef CONFIG_FPU
+       err |= rt_restore_fpu_state(uc);
+#endif
+
+       if (do_sigaltstack(&uc->uc_stack, NULL, usp) == -EFAULT)
+               goto badframe;
+
+       fsize = frame_extra_sizes[regs->format];
+       if (fsize < 0) {
+               /*
+                * user process trying to return with weird frame format
+                */
+#ifdef DEBUG
+               printk(KERN_DEBUG "user process returning with weird \
+                       frame format\n");
+#endif
+               goto badframe;
+       }
+
+       /* OK.  Make room on the supervisor stack for the extra junk,
+        * if necessary.
+        */
+
+       {
+#define frame_offset (sizeof(struct pt_regs)+sizeof(struct switch_stack))
+               __asm__ __volatile__
+                       ("   movel %0,%/sp\n\t"
+                        "   bra ret_from_signal\n"
+                        "4:\n"
+                        ".section __ex_table,\"a\"\n"
+                        "   .align 4\n"
+                        "   .long 2b,4b\n"
+                        ".previous"
+                        : /* no outputs, it doesn't ever return */
+                        : "a" (sw), "d" (fsize), "d" (frame_offset/4-1),
+                          "n" (frame_offset), "a" (&uc->uc_extra)
+                        : "a0");
+#undef frame_offset
+               /*
+                * If we ever get here an exception occurred while
+                * building the above stack-frame.
+                */
+               goto badframe;
+       }
+
+       *pd0 = regs->d0;
+       return err;
+
+badframe:
+       return 1;
+}
+
+asmlinkage int do_sigreturn(unsigned long __unused)
+{
+       struct switch_stack *sw = (struct switch_stack *) &__unused;
+       struct pt_regs *regs = (struct pt_regs *) (sw + 1);
+       unsigned long usp = rdusp();
+       struct sigframe __user *frame = (struct sigframe __user *)(usp - 4);
+       sigset_t set;
+       int d0;
+
+       if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
+               goto badframe;
+       if (__get_user(set.sig[0], &frame->sc.sc_mask) ||
+           (_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, frame + 1, &d0))
+               goto badframe;
+       return d0;
+
+badframe:
+       force_sig(SIGSEGV, current);
+       return 0;
+}
+
+asmlinkage int do_rt_sigreturn(unsigned long __unused)
+{
+       struct switch_stack *sw = (struct switch_stack *) &__unused;
+       struct pt_regs *regs = (struct pt_regs *) (sw + 1);
+       unsigned long usp = rdusp();
+       struct rt_sigframe __user *frame =
+               (struct rt_sigframe __user *)(usp - 4);
+       sigset_t set;
+       int d0;
+
+       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 (rt_restore_ucontext(regs, sw, &frame->uc, &d0))
+               goto badframe;
+       return d0;
+
+badframe:
+       force_sig(SIGSEGV, current);
+       return 0;
+}
+
+#ifdef CONFIG_FPU
+/*
+ * Set up a signal frame.
+ */
+
+static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs)
+{
+       if (FPU_IS_EMU) {
+               /* save registers */
+               memcpy(sc->sc_fpcntl, current->thread.fpcntl, 12);
+               memcpy(sc->sc_fpregs, current->thread.fp, 24);
+               return;
+       }
+}
+
+static inline int rt_save_fpu_state(struct ucontext __user *uc,
+       struct pt_regs *regs)
+{
+       int err = 0;
+
+       if (FPU_IS_EMU) {
+               /* save fpu control register */
+               err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpcntl,
+                               current->thread.fpcntl, 12);
+               /* save all other fpu register */
+               err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpregs,
+                               current->thread.fp, 96);
+               return err;
+       }
+
+       return err;
+}
+#endif
+
+static void setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs,
+                            unsigned long mask)
+{
+       sc->sc_mask = mask;
+       sc->sc_usp = rdusp();
+       sc->sc_d0 = regs->d0;
+       sc->sc_d1 = regs->d1;
+       sc->sc_a0 = regs->a0;
+       sc->sc_a1 = regs->a1;
+       sc->sc_sr = regs->sr;
+       sc->sc_pc = regs->pc;
+       sc->sc_formatvec = regs->format << 12 | regs->vector;
+#ifdef CONFIG_FPU
+       save_fpu_state(sc, regs);
+#endif
+}
+
+static inline int rt_setup_ucontext(struct ucontext __user *uc,
+       struct pt_regs *regs)
+{
+       struct switch_stack *sw = (struct switch_stack *)regs - 1;
+       greg_t __user *gregs = uc->uc_mcontext.gregs;
+       int err = 0;
+
+       err |= __put_user(MCONTEXT_VERSION, &uc->uc_mcontext.version);
+       err |= __put_user(regs->d0, &gregs[0]);
+       err |= __put_user(regs->d1, &gregs[1]);
+       err |= __put_user(regs->d2, &gregs[2]);
+       err |= __put_user(regs->d3, &gregs[3]);
+       err |= __put_user(regs->d4, &gregs[4]);
+       err |= __put_user(regs->d5, &gregs[5]);
+       err |= __put_user(sw->d6, &gregs[6]);
+       err |= __put_user(sw->d7, &gregs[7]);
+       err |= __put_user(regs->a0, &gregs[8]);
+       err |= __put_user(regs->a1, &gregs[9]);
+       err |= __put_user(regs->a2, &gregs[10]);
+       err |= __put_user(sw->a3, &gregs[11]);
+       err |= __put_user(sw->a4, &gregs[12]);
+       err |= __put_user(sw->a5, &gregs[13]);
+       err |= __put_user(sw->a6, &gregs[14]);
+       err |= __put_user(rdusp(), &gregs[15]);
+       err |= __put_user(regs->pc, &gregs[16]);
+       err |= __put_user(regs->sr, &gregs[17]);
+       err |= __put_user((regs->format << 12) | regs->vector,
+                         &uc->uc_formatvec);
+#ifdef CONFIG_FPU
+       err |= rt_save_fpu_state(uc, regs);
+#endif
+       return err;
+}
+
+static inline void push_cache(unsigned long vaddr)
+{
+#if 0 
+// JKM -- need to add into the old cpushl cache stuff
+       cf_cache_push(__pa(vaddr), 8);
+#endif
+}
+
+static inline void __user *
+get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size)
+{
+       unsigned long usp;
+
+       /* Default to using normal stack.  */
+       usp = rdusp();
+
+       /* This is the X/Open sanctioned signal stack switching.  */
+       if (ka->sa.sa_flags & SA_ONSTACK) {
+               if (!sas_ss_flags(usp))
+                       usp = current->sas_ss_sp + current->sas_ss_size;
+       }
+       return (void __user *)((usp - 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 fsize = frame_extra_sizes[regs->format];
+       struct sigcontext context;
+       int err = 0;
+
+       if (fsize < 0) {
+#ifdef DEBUG
+               printk(KERN_DEBUG "setup_frame: Unknown frame format %#x\n",
+                       regs->format);
+#endif
+               goto give_sigsegv;
+       }
+
+       frame = get_sigframe(ka, regs, sizeof(*frame));
+
+       err |= __put_user((current_thread_info()->exec_domain
+                       && current_thread_info()->exec_domain->signal_invmap
+                       && sig < 32
+                       ? current_thread_info()->exec_domain->signal_invmap[sig]
+                       : sig),
+                       &frame->sig);
+
+       err |= __put_user(regs->vector, &frame->code);
+       err |= __put_user(&frame->sc, &frame->psc);
+
+       if (_NSIG_WORDS > 1)
+               err |= copy_to_user(frame->extramask, &set->sig[1],
+                                   sizeof(frame->extramask));
+
+       setup_sigcontext(&context, regs, set->sig[0]);
+       err |= copy_to_user(&frame->sc, &context, sizeof(context));
+
+       /* Set up to return from userspace.  */
+       err |= __put_user(frame->retcode, &frame->pretcode);
+       /* moveq #,d0; trap #0 */
+       err |= __put_user(0x70004e40 + (__NR_sigreturn << 16),
+                         (long __user *)(frame->retcode));
+
+       if (err)
+               goto give_sigsegv;
+
+       push_cache((unsigned long) &frame->retcode);
+
+       /* Set up registers for signal handler */
+       wrusp((unsigned long) frame);
+       regs->pc = (unsigned long) ka->sa.sa_handler;
+
+adjust_stack:
+       /* Prepare to skip over the extra stuff in the exception frame.  */
+       if (regs->stkadj) {
+               struct pt_regs *tregs =
+                       (struct pt_regs *)((ulong)regs + regs->stkadj);
+#ifdef DEBUG
+               printk(KERN_DEBUG "Performing stackadjust=%04x\n",
+                       regs->stkadj);
+#endif
+               /* This must be copied with decreasing addresses to
+                  handle overlaps.  */
+               tregs->vector = 0;
+               tregs->format = 0;
+               tregs->pc = regs->pc;
+               tregs->sr = regs->sr;
+       }
+       return;
+
+give_sigsegv:
+       force_sigsegv(sig, current);
+       goto adjust_stack;
+}
+
+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 fsize = frame_extra_sizes[regs->format];
+       int err = 0;
+
+       if (fsize < 0) {
+#ifdef DEBUG
+               printk(KERN_DEBUG "setup_frame: Unknown frame format %#x\n",
+                       regs->format);
+#endif
+               goto give_sigsegv;
+       }
+
+       frame = get_sigframe(ka, regs, sizeof(*frame));
+
+       if (fsize) {
+               err |= copy_to_user(&frame->uc.uc_extra, regs + 1, fsize);
+               regs->stkadj = fsize;
+       }
+
+       err |= __put_user((current_thread_info()->exec_domain
+                       && current_thread_info()->exec_domain->signal_invmap
+                       && sig < 32
+                       ? current_thread_info()->exec_domain->signal_invmap[sig]
+                       : sig),
+                       &frame->sig);
+       err |= __put_user(&frame->info, &frame->pinfo);
+       err |= __put_user(&frame->uc, &frame->puc);
+       err |= copy_siginfo_to_user(&frame->info, info);
+
+       /* Create the ucontext.  */
+       err |= __put_user(0, &frame->uc.uc_flags);
+       err |= __put_user(NULL, &frame->uc.uc_link);
+       err |= __put_user((void __user *)current->sas_ss_sp,
+                         &frame->uc.uc_stack.ss_sp);
+       err |= __put_user(sas_ss_flags(rdusp()),
+                         &frame->uc.uc_stack.ss_flags);
+       err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
+       err |= rt_setup_ucontext(&frame->uc, regs);
+       err |= copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+
+       /* Set up to return from userspace.  */
+       err |= __put_user(frame->retcode, &frame->pretcode);
+
+       /* moveq #,d0; andi.l #,D0; trap #0 */
+       err |= __put_user(0x70AD0280, (long *)(frame->retcode + 0));
+       err |= __put_user(0x000000ff, (long *)(frame->retcode + 4));
+       err |= __put_user(0x4e400000, (long *)(frame->retcode + 8));
+
+       if (err)
+               goto give_sigsegv;
+
+       push_cache((unsigned long) &frame->retcode);
+
+       /* Set up registers for signal handler */
+       wrusp((unsigned long) frame);
+       regs->pc = (unsigned long) ka->sa.sa_handler;
+
+adjust_stack:
+       /* Prepare to skip over the extra stuff in the exception frame.  */
+       if (regs->stkadj) {
+               struct pt_regs *tregs =
+                       (struct pt_regs *)((ulong)regs + regs->stkadj);
+#ifdef DEBUG
+               printk(KERN_DEBUG "Performing stackadjust=%04x\n",
+                       regs->stkadj);
+#endif
+               /* This must be copied with decreasing addresses to
+                  handle overlaps.  */
+               tregs->vector = 0;
+               tregs->format = 0;
+               tregs->pc = regs->pc;
+               tregs->sr = regs->sr;
+       }
+       return;
+
+give_sigsegv:
+       force_sigsegv(sig, current);
+       goto adjust_stack;
+}
+
+static inline void
+handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler)
+{
+       switch (regs->d0) {
+       case -ERESTARTNOHAND:
+               if (!has_handler)
+                       goto do_restart;
+               regs->d0 = -EINTR;
+               break;
+
+       case -ERESTARTSYS:
+               if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) {
+                       regs->d0 = -EINTR;
+                       break;
+               }
+       /* fallthrough */
+       case -ERESTARTNOINTR:
+do_restart:
+               regs->d0 = regs->orig_d0;
+               regs->pc -= 2;
+               break;
+       }
+}
+
+/*
+ * OK, we're invoking a handler
+ */
+static void
+handle_signal(int sig, struct k_sigaction *ka, siginfo_t *info,
+             sigset_t *oldset, struct pt_regs *regs)
+{
+       /* are we from a system call? */
+       if (regs->orig_d0 >= 0)
+               /* If so, check system call restarting.. */
+               handle_restart(regs, ka, 1);
+
+       /* 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;
+
+       spin_lock_irq(&current->sighand->siglock);
+       sigorsets(&current->blocked, &current->blocked, &ka->sa.sa_mask);
+       if (!(ka->sa.sa_flags & SA_NODEFER))
+               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.
+ */
+asmlinkage int do_signal(sigset_t *oldset, struct pt_regs *regs)
+{
+       siginfo_t info;
+       struct k_sigaction ka;
+       int signr;
+
+       current->thread.esp0 = (unsigned long) regs;
+
+       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;
+       }
+
+       /* Did we come from a system call? */
+       if (regs->orig_d0 >= 0)
+               /* Restart the system call - no handlers present */
+               handle_restart(regs, NULL, 0);
+
+       return 0;
+}