- preempt_enable_no_resched();
- schedule();
- preempt_disable();
+ /*
+ * 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/slab.h>
+ #include <linux/fs.h>
+ #include <linux/smp.h>
+ #include <linux/stddef.h>
+ #include <linux/unistd.h>
+ #include <linux/ptrace.h>
+ #include <linux/user.h>
+ #include <linux/reboot.h>
+ #include <linux/init_task.h>
+ #include <linux/mqueue.h>
+
+ #include <asm/uaccess.h>
+ #include <asm/system.h>
+ #include <asm/traps.h>
+ #include <asm/machdep.h>
+ #include <asm/setup.h>
+ #include <asm/pgtable.h>
+
+
+ asmlinkage void ret_from_fork(void);
+
+
+ /*
+ * Return saved PC from a blocked thread
+ */
+ unsigned long thread_saved_pc(struct task_struct *tsk)
+ {
+ struct switch_stack *sw = (struct switch_stack *)tsk->thread.ksp;
+ /* Check whether the thread is blocked in resume() */
+ if (in_sched_functions(sw->retpc))
+ return ((unsigned long *)sw->a6)[1];
+ else
+ return sw->retpc;
+ }
+
+ /*
+ * The idle loop on an m68k..
+ */
+ static void default_idle(void)
+ {
+ if (!need_resched())
+ #if defined(MACH_ATARI_ONLY)
+ /* block out HSYNC on the atari (falcon) */
+ __asm__("stop #0x2200" : : : "cc");
+ #else
+ __asm__("stop #0x2000" : : : "cc");
+ #endif
+ }
+
+ void (*idle)(void) = default_idle;
+
+ /*
+ * The idle thread. There's no useful work to be
+ * done, so just try to conserve power and have a
+ * low exit latency (ie sit in a loop waiting for
+ * somebody to say that they'd like to reschedule)
+ */
+ void cpu_idle(void)
+ {
+ /* endless idle loop with no priority at all */
+ while (1) {
+ while (!need_resched())
+ idle();
++ schedule_preempt_disabled();
+ }
+ }
+
+ void machine_restart(char * __unused)
+ {
+ if (mach_reset)
+ mach_reset();
+ for (;;);
+ }
+
+ void machine_halt(void)
+ {
+ if (mach_halt)
+ mach_halt();
+ for (;;);
+ }
+
+ void machine_power_off(void)
+ {
+ if (mach_power_off)
+ mach_power_off();
+ for (;;);
+ }
+
+ void (*pm_power_off)(void) = machine_power_off;
+ EXPORT_SYMBOL(pm_power_off);
+
+ void show_regs(struct pt_regs * regs)
+ {
+ printk("\n");
+ printk("Format %02x Vector: %04x PC: %08lx Status: %04x %s\n",
+ regs->format, regs->vector, regs->pc, regs->sr, print_tainted());
+ printk("ORIG_D0: %08lx D0: %08lx A2: %08lx A1: %08lx\n",
+ regs->orig_d0, regs->d0, regs->a2, regs->a1);
+ printk("A0: %08lx D5: %08lx D4: %08lx\n",
+ regs->a0, regs->d5, regs->d4);
+ printk("D3: %08lx D2: %08lx D1: %08lx\n",
+ regs->d3, regs->d2, regs->d1);
+ if (!(regs->sr & PS_S))
+ printk("USP: %08lx\n", rdusp());
+ }
+
+ /*
+ * Create a kernel thread
+ */
+ int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
+ {
+ int pid;
+ mm_segment_t fs;
+
+ fs = get_fs();
+ set_fs (KERNEL_DS);
+
+ {
+ register long retval __asm__ ("d0");
+ register long clone_arg __asm__ ("d1") = flags | CLONE_VM | CLONE_UNTRACED;
+
+ retval = __NR_clone;
+ __asm__ __volatile__
+ ("clrl %%d2\n\t"
+ "trap #0\n\t" /* Linux/m68k system call */
+ "tstl %0\n\t" /* child or parent */
+ "jne 1f\n\t" /* parent - jump */
+ #ifdef CONFIG_MMU
+ "lea %%sp@(%c7),%6\n\t" /* reload current */
+ "movel %6@,%6\n\t"
+ #endif
+ "movel %3,%%sp@-\n\t" /* push argument */
+ "jsr %4@\n\t" /* call fn */
+ "movel %0,%%d1\n\t" /* pass exit value */
+ "movel %2,%%d0\n\t" /* exit */
+ "trap #0\n"
+ "1:"
+ : "+d" (retval)
+ : "i" (__NR_clone), "i" (__NR_exit),
+ "r" (arg), "a" (fn), "d" (clone_arg), "r" (current),
+ "i" (-THREAD_SIZE)
+ : "d2");
+
+ pid = retval;
+ }
+
+ set_fs (fs);
+ return pid;
+ }
+ EXPORT_SYMBOL(kernel_thread);
+
+ void flush_thread(void)
+ {
+ current->thread.fs = __USER_DS;
+ #ifdef CONFIG_FPU
+ if (!FPU_IS_EMU) {
+ unsigned long zero = 0;
+ asm volatile("frestore %0": :"m" (zero));
+ }
+ #endif
+ }
+
+ /*
+ * "m68k_fork()".. By the time we get here, the
+ * non-volatile registers have also been saved on the
+ * stack. We do some ugly pointer stuff here.. (see
+ * also copy_thread)
+ */
+
+ asmlinkage int m68k_fork(struct pt_regs *regs)
+ {
#ifdef CONFIG_MMU
- #include "process_mm.c"
+ return do_fork(SIGCHLD, rdusp(), regs, 0, NULL, NULL);
#else
- #include "process_no.c"
+ return -EINVAL;
#endif
+ }
+
+ asmlinkage int m68k_vfork(struct pt_regs *regs)
+ {
+ return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, rdusp(), regs, 0,
+ NULL, NULL);
+ }
+
+ asmlinkage int m68k_clone(struct pt_regs *regs)
+ {
+ unsigned long clone_flags;
+ unsigned long newsp;
+ int __user *parent_tidptr, *child_tidptr;
+
+ /* syscall2 puts clone_flags in d1 and usp in d2 */
+ clone_flags = regs->d1;
+ newsp = regs->d2;
+ parent_tidptr = (int __user *)regs->d3;
+ child_tidptr = (int __user *)regs->d4;
+ if (!newsp)
+ newsp = rdusp();
+ return do_fork(clone_flags, newsp, regs, 0,
+ parent_tidptr, child_tidptr);
+ }
+
+ int copy_thread(unsigned long clone_flags, unsigned long usp,
+ unsigned long unused,
+ struct task_struct * p, struct pt_regs * regs)
+ {
+ struct pt_regs * childregs;
+ struct switch_stack * childstack, *stack;
+ unsigned long *retp;
+
+ childregs = (struct pt_regs *) (task_stack_page(p) + THREAD_SIZE) - 1;
+
+ *childregs = *regs;
+ childregs->d0 = 0;
+
+ retp = ((unsigned long *) regs);
+ stack = ((struct switch_stack *) retp) - 1;
+
+ childstack = ((struct switch_stack *) childregs) - 1;
+ *childstack = *stack;
+ childstack->retpc = (unsigned long)ret_from_fork;
+
+ p->thread.usp = usp;
+ p->thread.ksp = (unsigned long)childstack;
+
+ if (clone_flags & CLONE_SETTLS)
+ task_thread_info(p)->tp_value = regs->d5;
+
+ /*
+ * Must save the current SFC/DFC value, NOT the value when
+ * the parent was last descheduled - RGH 10-08-96
+ */
+ p->thread.fs = get_fs().seg;
+
+ #ifdef CONFIG_FPU
+ if (!FPU_IS_EMU) {
+ /* Copy the current fpu state */
+ asm volatile ("fsave %0" : : "m" (p->thread.fpstate[0]) : "memory");
+
+ if (!CPU_IS_060 ? p->thread.fpstate[0] : p->thread.fpstate[2]) {
+ if (CPU_IS_COLDFIRE) {
+ asm volatile ("fmovemd %/fp0-%/fp7,%0\n\t"
+ "fmovel %/fpiar,%1\n\t"
+ "fmovel %/fpcr,%2\n\t"
+ "fmovel %/fpsr,%3"
+ :
+ : "m" (p->thread.fp[0]),
+ "m" (p->thread.fpcntl[0]),
+ "m" (p->thread.fpcntl[1]),
+ "m" (p->thread.fpcntl[2])
+ : "memory");
+ } else {
+ asm volatile ("fmovemx %/fp0-%/fp7,%0\n\t"
+ "fmoveml %/fpiar/%/fpcr/%/fpsr,%1"
+ :
+ : "m" (p->thread.fp[0]),
+ "m" (p->thread.fpcntl[0])
+ : "memory");
+ }
+ }
+
+ /* Restore the state in case the fpu was busy */
+ asm volatile ("frestore %0" : : "m" (p->thread.fpstate[0]));
+ }
+ #endif /* CONFIG_FPU */
+
+ return 0;
+ }
+
+ /* Fill in the fpu structure for a core dump. */
+ #ifdef CONFIG_FPU
+ int dump_fpu (struct pt_regs *regs, struct user_m68kfp_struct *fpu)
+ {
+ char fpustate[216];
+
+ if (FPU_IS_EMU) {
+ int i;
+
+ memcpy(fpu->fpcntl, current->thread.fpcntl, 12);
+ memcpy(fpu->fpregs, current->thread.fp, 96);
+ /* Convert internal fpu reg representation
+ * into long double format
+ */
+ for (i = 0; i < 24; i += 3)
+ fpu->fpregs[i] = ((fpu->fpregs[i] & 0xffff0000) << 15) |
+ ((fpu->fpregs[i] & 0x0000ffff) << 16);
+ return 1;
+ }
+
+ /* First dump the fpu context to avoid protocol violation. */
+ asm volatile ("fsave %0" :: "m" (fpustate[0]) : "memory");
+ if (!CPU_IS_060 ? !fpustate[0] : !fpustate[2])
+ return 0;
+
+ if (CPU_IS_COLDFIRE) {
+ asm volatile ("fmovel %/fpiar,%0\n\t"
+ "fmovel %/fpcr,%1\n\t"
+ "fmovel %/fpsr,%2\n\t"
+ "fmovemd %/fp0-%/fp7,%3"
+ :
+ : "m" (fpu->fpcntl[0]),
+ "m" (fpu->fpcntl[1]),
+ "m" (fpu->fpcntl[2]),
+ "m" (fpu->fpregs[0])
+ : "memory");
+ } else {
+ asm volatile ("fmovem %/fpiar/%/fpcr/%/fpsr,%0"
+ :
+ : "m" (fpu->fpcntl[0])
+ : "memory");
+ asm volatile ("fmovemx %/fp0-%/fp7,%0"
+ :
+ : "m" (fpu->fpregs[0])
+ : "memory");
+ }
+
+ return 1;
+ }
+ EXPORT_SYMBOL(dump_fpu);
+ #endif /* CONFIG_FPU */
+
+ /*
+ * sys_execve() executes a new program.
+ */
+ asmlinkage int sys_execve(const char __user *name,
+ const char __user *const __user *argv,
+ const char __user *const __user *envp)
+ {
+ int error;
+ char * filename;
+ struct pt_regs *regs = (struct pt_regs *) &name;
+
+ filename = getname(name);
+ error = PTR_ERR(filename);
+ if (IS_ERR(filename))
+ return error;
+ error = do_execve(filename, argv, envp, regs);
+ putname(filename);
+ return error;
+ }
+
+ 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)task_stack_page(p);
+ fp = ((struct switch_stack *)p->thread.ksp)->a6;
+ 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;
+ }
projects / karo-tx-linux.git / commitdiff