[PATCH v9 05/17] h8300: process and signals
From: Yoshinori Sato
Date: Mon Apr 27 2015 - 01:39:42 EST
process management helper and signal handling
Signed-off-by: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
---
arch/h8300/kernel/process.c | 171 ++++++++++++++++++++++++++
arch/h8300/kernel/ptrace.c | 203 +++++++++++++++++++++++++++++++
arch/h8300/kernel/signal.c | 289 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 663 insertions(+)
create mode 100644 arch/h8300/kernel/process.c
create mode 100644 arch/h8300/kernel/ptrace.c
create mode 100644 arch/h8300/kernel/signal.c
diff --git a/arch/h8300/kernel/process.c b/arch/h8300/kernel/process.c
new file mode 100644
index 0000000..dee4125
--- /dev/null
+++ b/arch/h8300/kernel/process.c
@@ -0,0 +1,171 @@
+/*
+ * linux/arch/h8300/kernel/process.c
+ *
+ * Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
+ *
+ * Based on:
+ *
+ * linux/arch/m68knommu/kernel/process.c
+ *
+ * Copyright (C) 1998 D. Jeff Dionne <jeff@xxxxxxxxxxxxxxxxxxxx>,
+ * Kenneth Albanowski <kjahds@xxxxxxxxxx>,
+ * The Silver Hammer Group, Ltd.
+ *
+ * linux/arch/m68k/kernel/process.c
+ *
+ * Copyright (C) 1995 Hamish Macdonald
+ *
+ * 68060 fixes by Jesper Skov
+ */
+
+/*
+ * This file handles the architecture-dependent parts of process handling..
+ */
+
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/stddef.h>
+#include <linux/unistd.h>
+#include <linux/ptrace.h>
+#include <linux/user.h>
+#include <linux/interrupt.h>
+#include <linux/reboot.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/rcupdate.h>
+
+#include <asm/uaccess.h>
+#include <asm/traps.h>
+#include <asm/setup.h>
+#include <asm/pgtable.h>
+
+void (*pm_power_off)(void) = NULL;
+EXPORT_SYMBOL(pm_power_off);
+
+asmlinkage void ret_from_fork(void);
+asmlinkage void ret_from_kernel_thread(void);
+
+/*
+ * The idle loop on an H8/300..
+ */
+void arch_cpu_idle(void)
+{
+ local_irq_enable();
+ __asm__("sleep");
+}
+
+void machine_restart(char *__unused)
+{
+ local_irq_disable();
+ __asm__("jmp @@0");
+}
+
+void machine_halt(void)
+{
+ local_irq_disable();
+ __asm__("sleep");
+ for (;;)
+ ;
+}
+
+void machine_power_off(void)
+{
+ local_irq_disable();
+ __asm__("sleep");
+ for (;;)
+ ;
+}
+
+void show_regs(struct pt_regs *regs)
+{
+ show_regs_print_info(KERN_DEFAULT);
+
+ pr_notice("\n");
+ pr_notice("PC: %08lx Status: %02x\n",
+ regs->pc, regs->ccr);
+ pr_notice("ORIG_ER0: %08lx ER0: %08lx ER1: %08lx\n",
+ regs->orig_er0, regs->er0, regs->er1);
+ pr_notice("ER2: %08lx ER3: %08lx ER4: %08lx ER5: %08lx\n",
+ regs->er2, regs->er3, regs->er4, regs->er5);
+ pr_notice("ER6' %08lx ", regs->er6);
+ if (user_mode(regs))
+ printk("USP: %08lx\n", rdusp());
+ else
+ printk("\n");
+}
+
+void flush_thread(void)
+{
+}
+
+int copy_thread(unsigned long clone_flags,
+ unsigned long usp, unsigned long topstk,
+ struct task_struct *p)
+{
+ struct pt_regs *childregs;
+
+ childregs = (struct pt_regs *) (THREAD_SIZE + task_stack_page(p)) - 1;
+
+ if (unlikely(p->flags & PF_KTHREAD)) {
+ memset(childregs, 0, sizeof(struct pt_regs));
+ childregs->retpc = (unsigned long) ret_from_kernel_thread;
+ childregs->er4 = topstk; /* arg */
+ childregs->er5 = usp; /* fn */
+ } else {
+ *childregs = *current_pt_regs();
+ childregs->er0 = 0;
+ childregs->retpc = (unsigned long) ret_from_fork;
+ p->thread.usp = usp ?: rdusp();
+ }
+ p->thread.ksp = (unsigned long)childregs;
+
+ return 0;
+}
+
+unsigned long thread_saved_pc(struct task_struct *tsk)
+{
+ return ((struct pt_regs *)tsk->thread.esp0)->pc;
+}
+
+unsigned long get_wchan(struct task_struct *p)
+{
+ unsigned long fp, pc;
+ unsigned long stack_page;
+ int count = 0;
+
+ if (!p || p == current || p->state == TASK_RUNNING)
+ return 0;
+
+ stack_page = (unsigned long)p;
+ fp = ((struct pt_regs *)p->thread.ksp)->er6;
+ do {
+ if (fp < stack_page+sizeof(struct thread_info) ||
+ fp >= 8184+stack_page)
+ return 0;
+ pc = ((unsigned long *)fp)[1];
+ if (!in_sched_functions(pc))
+ return pc;
+ fp = *(unsigned long *) fp;
+ } while (count++ < 16);
+ return 0;
+}
+
+/* generic sys_clone is not enough registers */
+asmlinkage int sys_clone(unsigned long __user *args)
+{
+ unsigned long clone_flags;
+ unsigned long newsp;
+ uintptr_t parent_tidptr;
+ uintptr_t child_tidptr;
+
+ get_user(clone_flags, &args[0]);
+ get_user(newsp, &args[1]);
+ get_user(parent_tidptr, &args[2]);
+ get_user(child_tidptr, &args[3]);
+ return do_fork(clone_flags, newsp, 0,
+ (int __user *)parent_tidptr, (int __user *)child_tidptr);
+}
diff --git a/arch/h8300/kernel/ptrace.c b/arch/h8300/kernel/ptrace.c
new file mode 100644
index 0000000..9207554
--- /dev/null
+++ b/arch/h8300/kernel/ptrace.c
@@ -0,0 +1,203 @@
+/*
+ * linux/arch/h8300/kernel/ptrace.c
+ *
+ * Copyright 2015 Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
+ *
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/audit.h>
+#include <linux/tracehook.h>
+#include <linux/regset.h>
+#include <linux/elf.h>
+
+#define CCR_MASK 0x6f /* mode/imask not set */
+#define EXR_MASK 0x80 /* modify only T */
+
+#define PT_REG(r) offsetof(struct pt_regs, r)
+
+extern void user_disable_single_step(struct task_struct *child);
+
+/* Mapping from PT_xxx to the stack offset at which the register is
+ saved. Notice that usp has no stack-slot and needs to be treated
+ specially (see get_reg/put_reg below). */
+static const int register_offset[] = {
+ PT_REG(er1), PT_REG(er2), PT_REG(er3), PT_REG(er4),
+ PT_REG(er5), PT_REG(er6), PT_REG(er0), -1,
+ PT_REG(orig_er0), PT_REG(ccr), PT_REG(pc),
+#if defined(CONFIG_CPU_H8S)
+ PT_REG(exr),
+#endif
+};
+
+/* read register */
+long h8300_get_reg(struct task_struct *task, int regno)
+{
+ switch (regno) {
+ case PT_USP:
+ return task->thread.usp + sizeof(long)*2;
+ case PT_CCR:
+ case PT_EXR:
+ return *(unsigned short *)(task->thread.esp0 +
+ register_offset[regno]);
+ default:
+ return *(unsigned long *)(task->thread.esp0 +
+ register_offset[regno]);
+ }
+}
+
+int h8300_put_reg(struct task_struct *task, int regno, unsigned long data)
+{
+ unsigned short oldccr;
+ unsigned short oldexr;
+
+ switch (regno) {
+ case PT_USP:
+ task->thread.usp = data - sizeof(long)*2;
+ case PT_CCR:
+ oldccr = *(unsigned short *)(task->thread.esp0 +
+ register_offset[regno]);
+ oldccr &= ~CCR_MASK;
+ data &= CCR_MASK;
+ data |= oldccr;
+ *(unsigned short *)(task->thread.esp0 +
+ register_offset[regno]) = data;
+ break;
+ case PT_EXR:
+ oldexr = *(unsigned short *)(task->thread.esp0 +
+ register_offset[regno]);
+ oldccr &= ~EXR_MASK;
+ data &= EXR_MASK;
+ data |= oldexr;
+ *(unsigned short *)(task->thread.esp0 +
+ register_offset[regno]) = data;
+ break;
+ default:
+ *(unsigned long *)(task->thread.esp0 +
+ register_offset[regno]) = data;
+ break;
+ }
+ return 0;
+}
+
+static int regs_get(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ void *kbuf, void __user *ubuf)
+{
+ int r;
+ struct user_regs_struct regs;
+ long *reg = (long *)®s;
+
+ /* build user regs in buffer */
+ for (r = 0; r < ARRAY_SIZE(register_offset); r++)
+ *reg++ = h8300_get_reg(target, r);
+
+ return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+ ®s, 0, sizeof(regs));
+}
+
+static int regs_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ int r;
+ int ret;
+ struct user_regs_struct regs;
+ long *reg;
+
+ /* build user regs in buffer */
+ for (reg = (long *)®s, r = 0; r < ARRAY_SIZE(register_offset); r++)
+ *reg++ = h8300_get_reg(target, r);
+
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ ®s, 0, sizeof(regs));
+ if (ret)
+ return ret;
+
+ /* write back to pt_regs */
+ for (reg = (long *)®s, r = 0; r < ARRAY_SIZE(register_offset); r++)
+ h8300_put_reg(target, r, *reg++);
+ return 0;
+}
+
+enum h8300_regset {
+ REGSET_GENERAL,
+};
+
+static const struct user_regset h8300_regsets[] = {
+ [REGSET_GENERAL] = {
+ .core_note_type = NT_PRSTATUS,
+ .n = ELF_NGREG,
+ .size = sizeof(long),
+ .align = sizeof(long),
+ .get = regs_get,
+ .set = regs_set,
+ },
+};
+
+static const struct user_regset_view user_h8300_native_view = {
+ .name = "h8300",
+ .e_machine = EM_H8_300,
+ .regsets = h8300_regsets,
+ .n = ARRAY_SIZE(h8300_regsets),
+};
+
+const struct user_regset_view *task_user_regset_view(struct task_struct *task)
+{
+ return &user_h8300_native_view;
+}
+
+void ptrace_disable(struct task_struct *child)
+{
+ user_disable_single_step(child);
+}
+
+long arch_ptrace(struct task_struct *child, long request,
+ unsigned long addr, unsigned long data)
+{
+ int ret;
+
+ switch (request) {
+ default:
+ ret = ptrace_request(child, request, addr, data);
+ break;
+ }
+ return ret;
+}
+
+asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
+{
+ long ret = 0;
+
+ if (test_thread_flag(TIF_SYSCALL_TRACE) &&
+ tracehook_report_syscall_entry(regs))
+ /*
+ * Tracing decided this syscall should not happen.
+ * We'll return a bogus call number to get an ENOSYS
+ * error, but leave the original number in regs->regs[0].
+ */
+ ret = -1L;
+
+ audit_syscall_entry(regs->er1, regs->er2, regs->er3,
+ regs->er4, regs->er5);
+
+ return ret ?: regs->er0;
+}
+
+asmlinkage void do_syscall_trace_leave(struct pt_regs *regs)
+{
+ int step;
+
+ audit_syscall_exit(regs);
+
+ step = test_thread_flag(TIF_SINGLESTEP);
+ if (step || test_thread_flag(TIF_SYSCALL_TRACE))
+ tracehook_report_syscall_exit(regs, step);
+}
diff --git a/arch/h8300/kernel/signal.c b/arch/h8300/kernel/signal.c
new file mode 100644
index 0000000..380fffd
--- /dev/null
+++ b/arch/h8300/kernel/signal.c
@@ -0,0 +1,289 @@
+/*
+ * linux/arch/h8300/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.
+ */
+
+/*
+ * uClinux H8/300 support by Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
+ * and David McCullough <davidm@xxxxxxxxxxxx>
+ *
+ * Based on
+ * Linux/m68k by Hamish Macdonald
+ */
+
+/*
+ * ++roman (07/09/96): implemented signal stacks (specially for tosemu on
+ * Atari :-) Current limitation: Only one sigstack can be active at one time.
+ * If a second signal with SA_ONSTACK set arrives while working on a sigstack,
+ * SA_ONSTACK is ignored. This behaviour avoids lots of trouble with nested
+ * signal handlers!
+ */
+
+#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 <linux/tracehook.h>
+
+#include <asm/setup.h>
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/traps.h>
+#include <asm/ucontext.h>
+
+/*
+ * 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 rt_sigframe {
+ long dummy_er0;
+ long dummy_vector;
+#if defined(CONFIG_CPU_H8S)
+ short dummy_exr;
+#endif
+ long dummy_pc;
+ char *pretcode;
+ struct siginfo *pinfo;
+ void *puc;
+ unsigned char retcode[8];
+ struct siginfo info;
+ struct ucontext uc;
+ int sig;
+} __packed __aligned(2);
+
+static inline int
+restore_sigcontext(struct sigcontext *usc, int *pd0)
+{
+ struct pt_regs *regs = current_pt_regs();
+ int err = 0;
+ unsigned int ccr;
+ unsigned int usp;
+ unsigned int er0;
+
+ /* Always make any pending restarted system calls return -EINTR */
+ current_thread_info()->restart_block.fn = do_no_restart_syscall;
+
+ /* restore passed registers */
+#define COPY(r) do { err |= get_user(regs->r, &usc->sc_##r); } while (0)
+ COPY(er1);
+ COPY(er2);
+ COPY(er3);
+ COPY(er5);
+ COPY(pc);
+ ccr = regs->ccr & 0x10;
+ COPY(ccr);
+#undef COPY
+ regs->ccr &= 0xef;
+ regs->ccr |= ccr;
+ regs->orig_er0 = -1; /* disable syscall checks */
+ err |= __get_user(usp, &usc->sc_usp);
+ wrusp(usp);
+
+ err |= __get_user(er0, &usc->sc_er0);
+ *pd0 = er0;
+ return err;
+}
+
+asmlinkage int sys_rt_sigreturn(void)
+{
+ unsigned long usp = rdusp();
+ struct rt_sigframe *frame = (struct rt_sigframe *)(usp - 4);
+ sigset_t set;
+ int er0;
+
+ 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(&frame->uc.uc_mcontext, &er0))
+ goto badframe;
+
+ if (restore_altstack(&frame->uc.uc_stack))
+ goto badframe;
+
+ return er0;
+
+badframe:
+ force_sig(SIGSEGV, current);
+ return 0;
+}
+
+static int setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
+ unsigned long mask)
+{
+ int err = 0;
+
+ err |= __put_user(regs->er0, &sc->sc_er0);
+ err |= __put_user(regs->er1, &sc->sc_er1);
+ err |= __put_user(regs->er2, &sc->sc_er2);
+ err |= __put_user(regs->er3, &sc->sc_er3);
+ err |= __put_user(regs->er4, &sc->sc_er4);
+ err |= __put_user(regs->er5, &sc->sc_er5);
+ err |= __put_user(regs->er6, &sc->sc_er6);
+ err |= __put_user(rdusp(), &sc->sc_usp);
+ err |= __put_user(regs->pc, &sc->sc_pc);
+ err |= __put_user(regs->ccr, &sc->sc_ccr);
+ err |= __put_user(mask, &sc->sc_mask);
+
+ return err;
+}
+
+static inline void __user *
+get_sigframe(struct ksignal *ksig, struct pt_regs *regs, size_t frame_size)
+{
+ return (void __user *)((sigsp(rdusp(), ksig) - frame_size) & -8UL);
+}
+
+static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
+ struct pt_regs *regs)
+{
+ struct rt_sigframe *frame;
+ int err = 0;
+ unsigned char *ret;
+
+ frame = get_sigframe(ksig, regs, sizeof(*frame));
+
+ if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+ return -EFAULT;
+
+ 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(0, &frame->uc.uc_link);
+ err |= __save_altstack(&frame->uc.uc_stack, rdusp());
+ err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, set->sig[0]);
+ err |= copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+ if (err)
+ return -EFAULT;
+
+ /* Set up to return from userspace. */
+ ret = frame->retcode;
+ if (ksig->ka.sa.sa_flags & SA_RESTORER)
+ ret = (unsigned char *)(ksig->ka.sa.sa_restorer);
+ else {
+ /* sub.l er0,er0; mov.b #__NR_rt_sigreturn,r0l; trapa #0 */
+ err |= __put_user(0x1a80f800 + (__NR_rt_sigreturn & 0xff),
+ (unsigned long *)(frame->retcode + 0));
+ err |= __put_user(0x5700,
+ (unsigned short *)(frame->retcode + 4));
+ }
+ err |= __put_user(ret, &frame->pretcode);
+
+ if (err)
+ return -EFAULT;
+
+ /* Set up registers for signal handler */
+ wrusp((unsigned long) frame);
+ regs->pc = (unsigned long) ksig->ka.sa.sa_handler;
+ regs->er0 = ksig->sig;
+ regs->er1 = (unsigned long)&(frame->info);
+ regs->er2 = (unsigned long)&frame->uc;
+ regs->er5 = current->mm->start_data; /* GOT base */
+
+ return 0;
+}
+
+static void
+handle_restart(struct pt_regs *regs, struct k_sigaction *ka)
+{
+ switch (regs->er0) {
+ case -ERESTARTNOHAND:
+ if (!ka)
+ goto do_restart;
+ regs->er0 = -EINTR;
+ break;
+ case -ERESTART_RESTARTBLOCK:
+ if (!ka) {
+ regs->er0 = __NR_restart_syscall;
+ regs->pc -= 2;
+ } else
+ regs->er0 = -EINTR;
+ break;
+ case -ERESTARTSYS:
+ if (!(ka->sa.sa_flags & SA_RESTART)) {
+ regs->er0 = -EINTR;
+ break;
+ }
+ /* fallthrough */
+ case -ERESTARTNOINTR:
+do_restart:
+ regs->er0 = regs->orig_er0;
+ regs->pc -= 2;
+ break;
+ }
+}
+
+/*
+ * OK, we're invoking a handler
+ */
+static void
+handle_signal(struct ksignal *ksig, struct pt_regs *regs)
+{
+ sigset_t *oldset = sigmask_to_save();
+ int ret;
+ /* are we from a system call? */
+ if (regs->orig_er0 >= 0)
+ handle_restart(regs, &ksig->ka);
+
+ ret = setup_rt_frame(ksig, oldset, regs);
+
+ signal_setup_done(ret, ksig, 0);
+}
+
+/*
+ * 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.
+ */
+static void do_signal(struct pt_regs *regs)
+{
+ struct ksignal ksig;
+
+ current->thread.esp0 = (unsigned long) regs;
+
+ if (get_signal(&ksig)) {
+ /* Whee! Actually deliver the signal. */
+ handle_signal(&ksig, regs);
+ return;
+ }
+ /* Did we come from a system call? */
+ if (regs->orig_er0 >= 0)
+ handle_restart(regs, NULL);
+
+ /* If there's no signal to deliver, we just restore the saved mask. */
+ restore_saved_sigmask();
+}
+
+asmlinkage void do_notify_resume(struct pt_regs *regs, u32 thread_info_flags)
+{
+ if (thread_info_flags & _TIF_SIGPENDING)
+ do_signal(regs);
+
+ if (thread_info_flags & _TIF_NOTIFY_RESUME) {
+ clear_thread_flag(TIF_NOTIFY_RESUME);
+ tracehook_notify_resume(regs);
+ }
+}
--
2.1.4
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