v4.19.13 snapshot.
diff --git a/arch/openrisc/kernel/signal.c b/arch/openrisc/kernel/signal.c
new file mode 100644
index 0000000..265f10f
--- /dev/null
+++ b/arch/openrisc/kernel/signal.c
@@ -0,0 +1,326 @@
+/*
+ * OpenRISC signal.c
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others. All original copyrights apply as per the original source
+ * declaration.
+ *
+ * Modifications for the OpenRISC architecture:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.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/tracehook.h>
+
+#include <asm/processor.h>
+#include <asm/syscall.h>
+#include <asm/ucontext.h>
+#include <linux/uaccess.h>
+
+#define DEBUG_SIG 0
+
+struct rt_sigframe {
+ struct siginfo info;
+ struct ucontext uc;
+ unsigned char retcode[16]; /* trampoline code */
+};
+
+static int restore_sigcontext(struct pt_regs *regs,
+ struct sigcontext __user *sc)
+{
+ int err = 0;
+
+ /* Always make any pending restarted system calls return -EINTR */
+ current->restart_block.fn = do_no_restart_syscall;
+
+ /*
+ * Restore the regs from &sc->regs.
+ * (sc is already checked for VERIFY_READ since the sigframe was
+ * checked in sys_sigreturn previously)
+ */
+ err |= __copy_from_user(regs, sc->regs.gpr, 32 * sizeof(unsigned long));
+ err |= __copy_from_user(®s->pc, &sc->regs.pc, sizeof(unsigned long));
+ err |= __copy_from_user(®s->sr, &sc->regs.sr, sizeof(unsigned long));
+
+ /* make sure the SM-bit is cleared so user-mode cannot fool us */
+ regs->sr &= ~SPR_SR_SM;
+
+ regs->orig_gpr11 = -1; /* Avoid syscall restart checks */
+
+ /* TODO: the other ports use regs->orig_XX to disable syscall checks
+ * after this completes, but we don't use that mechanism. maybe we can
+ * use it now ?
+ */
+
+ return err;
+}
+
+asmlinkage long _sys_rt_sigreturn(struct pt_regs *regs)
+{
+ struct rt_sigframe *frame = (struct rt_sigframe __user *)regs->sp;
+ sigset_t set;
+
+ /*
+ * Since we stacked the signal on a dword boundary,
+ * then frame should be dword aligned here. If it's
+ * not, then the user is trying to mess with us.
+ */
+ if (((long)frame) & 3)
+ goto badframe;
+
+ 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(regs, &frame->uc.uc_mcontext))
+ goto badframe;
+
+ if (restore_altstack(&frame->uc.uc_stack))
+ goto badframe;
+
+ return regs->gpr[11];
+
+badframe:
+ force_sig(SIGSEGV, current);
+ return 0;
+}
+
+/*
+ * Set up a signal frame.
+ */
+
+static int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
+{
+ int err = 0;
+
+ /* copy the regs */
+ /* There should be no need to save callee-saved registers here...
+ * ...but we save them anyway. Revisit this
+ */
+ err |= __copy_to_user(sc->regs.gpr, regs, 32 * sizeof(unsigned long));
+ err |= __copy_to_user(&sc->regs.pc, ®s->pc, sizeof(unsigned long));
+ err |= __copy_to_user(&sc->regs.sr, ®s->sr, sizeof(unsigned long));
+
+ return err;
+}
+
+static inline unsigned long align_sigframe(unsigned long sp)
+{
+ return sp & ~3UL;
+}
+
+/*
+ * Work out where the signal frame should go. It's either on the user stack
+ * or the alternate stack.
+ */
+
+static inline void __user *get_sigframe(struct ksignal *ksig,
+ struct pt_regs *regs, size_t frame_size)
+{
+ unsigned long sp = regs->sp;
+
+ /* redzone */
+ sp -= STACK_FRAME_OVERHEAD;
+ sp = sigsp(sp, ksig);
+ sp = align_sigframe(sp - frame_size);
+
+ return (void __user *)sp;
+}
+
+/* grab and setup a signal frame.
+ *
+ * basically we stack a lot of state info, and arrange for the
+ * user-mode program to return to the kernel using either a
+ * trampoline which performs the syscall sigreturn, or a provided
+ * user-mode trampoline.
+ */
+static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
+ struct pt_regs *regs)
+{
+ struct rt_sigframe *frame;
+ unsigned long return_ip;
+ int err = 0;
+
+ frame = get_sigframe(ksig, regs, sizeof(*frame));
+
+ if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+ return -EFAULT;
+
+ /* Create siginfo. */
+ 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(NULL, &frame->uc.uc_link);
+ err |= __save_altstack(&frame->uc.uc_stack, regs->sp);
+ err |= setup_sigcontext(regs, &frame->uc.uc_mcontext);
+
+ err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+
+ if (err)
+ return -EFAULT;
+
+ /* trampoline - the desired return ip is the retcode itself */
+ return_ip = (unsigned long)&frame->retcode;
+ /* This is:
+ l.ori r11,r0,__NR_sigreturn
+ l.sys 1
+ */
+ err |= __put_user(0xa960, (short *)(frame->retcode + 0));
+ err |= __put_user(__NR_rt_sigreturn, (short *)(frame->retcode + 2));
+ err |= __put_user(0x20000001, (unsigned long *)(frame->retcode + 4));
+ err |= __put_user(0x15000000, (unsigned long *)(frame->retcode + 8));
+
+ if (err)
+ return -EFAULT;
+
+ /* Set up registers for signal handler */
+ regs->pc = (unsigned long)ksig->ka.sa.sa_handler; /* what we enter NOW */
+ regs->gpr[9] = (unsigned long)return_ip; /* what we enter LATER */
+ regs->gpr[3] = (unsigned long)ksig->sig; /* arg 1: signo */
+ regs->gpr[4] = (unsigned long)&frame->info; /* arg 2: (siginfo_t*) */
+ regs->gpr[5] = (unsigned long)&frame->uc; /* arg 3: ucontext */
+
+ /* actually move the usp to reflect the stacked frame */
+ regs->sp = (unsigned long)frame;
+
+ return 0;
+}
+
+static inline void
+handle_signal(struct ksignal *ksig, struct pt_regs *regs)
+{
+ int ret;
+
+ ret = setup_rt_frame(ksig, sigmask_to_save(), regs);
+
+ signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLESTEP));
+}
+
+/*
+ * 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.
+ *
+ * Also note that the regs structure given here as an argument, is the latest
+ * pushed pt_regs. It may or may not be the same as the first pushed registers
+ * when the initial usermode->kernelmode transition took place. Therefore
+ * we can use user_mode(regs) to see if we came directly from kernel or user
+ * mode below.
+ */
+
+int do_signal(struct pt_regs *regs, int syscall)
+{
+ struct ksignal ksig;
+ unsigned long continue_addr = 0;
+ unsigned long restart_addr = 0;
+ unsigned long retval = 0;
+ int restart = 0;
+
+ if (syscall) {
+ continue_addr = regs->pc;
+ restart_addr = continue_addr - 4;
+ retval = regs->gpr[11];
+
+ /*
+ * Setup syscall restart here so that a debugger will
+ * see the already changed PC.
+ */
+ switch (retval) {
+ case -ERESTART_RESTARTBLOCK:
+ restart = -2;
+ /* Fall through */
+ case -ERESTARTNOHAND:
+ case -ERESTARTSYS:
+ case -ERESTARTNOINTR:
+ restart++;
+ regs->gpr[11] = regs->orig_gpr11;
+ regs->pc = restart_addr;
+ break;
+ }
+ }
+
+ /*
+ * Get the signal to deliver. During the call to get_signal the
+ * debugger may change all our registers so we may need to revert
+ * the decision to restart the syscall; specifically, if the PC is
+ * changed, don't restart the syscall.
+ */
+ if (get_signal(&ksig)) {
+ if (unlikely(restart) && regs->pc == restart_addr) {
+ if (retval == -ERESTARTNOHAND ||
+ retval == -ERESTART_RESTARTBLOCK
+ || (retval == -ERESTARTSYS
+ && !(ksig.ka.sa.sa_flags & SA_RESTART))) {
+ /* No automatic restart */
+ regs->gpr[11] = -EINTR;
+ regs->pc = continue_addr;
+ }
+ }
+ handle_signal(&ksig, regs);
+ } else {
+ /* no handler */
+ restore_saved_sigmask();
+ /*
+ * Restore pt_regs PC as syscall restart will be handled by
+ * kernel without return to userspace
+ */
+ if (unlikely(restart) && regs->pc == restart_addr) {
+ regs->pc = continue_addr;
+ return restart;
+ }
+ }
+
+ return 0;
+}
+
+asmlinkage int
+do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall)
+{
+ do {
+ if (likely(thread_flags & _TIF_NEED_RESCHED)) {
+ schedule();
+ } else {
+ if (unlikely(!user_mode(regs)))
+ return 0;
+ local_irq_enable();
+ if (thread_flags & _TIF_SIGPENDING) {
+ int restart = do_signal(regs, syscall);
+ if (unlikely(restart)) {
+ /*
+ * Restart without handlers.
+ * Deal with it without leaving
+ * the kernel space.
+ */
+ return restart;
+ }
+ syscall = 0;
+ } else {
+ clear_thread_flag(TIF_NOTIFY_RESUME);
+ tracehook_notify_resume(regs);
+ }
+ }
+ local_irq_disable();
+ thread_flags = current_thread_info()->flags;
+ } while (thread_flags & _TIF_WORK_MASK);
+ return 0;
+}