| /* | 
 |  *  linux/arch/m68knommu/kernel/process.c | 
 |  * | 
 |  *  Copyright (C) 1995  Hamish Macdonald | 
 |  * | 
 |  *  68060 fixes by Jesper Skov | 
 |  * | 
 |  *  uClinux changes | 
 |  *  Copyright (C) 2000-2002, David McCullough <davidm@snapgear.com> | 
 |  */ | 
 |  | 
 | /* | 
 |  * This file handles the architecture-dependent parts of process handling.. | 
 |  */ | 
 |  | 
 | #include <linux/module.h> | 
 | #include <linux/errno.h> | 
 | #include <linux/sched.h> | 
 | #include <linux/kernel.h> | 
 | #include <linux/mm.h> | 
 | #include <linux/smp.h> | 
 | #include <linux/smp_lock.h> | 
 | #include <linux/stddef.h> | 
 | #include <linux/unistd.h> | 
 | #include <linux/ptrace.h> | 
 | #include <linux/slab.h> | 
 | #include <linux/user.h> | 
 | #include <linux/a.out.h> | 
 | #include <linux/interrupt.h> | 
 | #include <linux/reboot.h> | 
 | #include <linux/fs.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); | 
 |  | 
 | /* | 
 |  * The following aren't currently used. | 
 |  */ | 
 | void (*pm_idle)(void); | 
 | EXPORT_SYMBOL(pm_idle); | 
 |  | 
 | void (*pm_power_off)(void); | 
 | EXPORT_SYMBOL(pm_power_off); | 
 |  | 
 | /* | 
 |  * The idle loop on an m68knommu.. | 
 |  */ | 
 | static void default_idle(void) | 
 | { | 
 | 	local_irq_disable(); | 
 |  	while (!need_resched()) { | 
 | 		/* This stop will re-enable interrupts */ | 
 |  		__asm__("stop #0x2000" : : : "cc"); | 
 | 		local_irq_disable(); | 
 | 	} | 
 | 	local_irq_enable(); | 
 | } | 
 |  | 
 | 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) { | 
 | 		idle(); | 
 | 		preempt_enable_no_resched(); | 
 | 		schedule(); | 
 | 		preempt_disable(); | 
 | 	} | 
 | } | 
 |  | 
 | 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 show_regs(struct pt_regs * regs) | 
 | { | 
 | 	printk(KERN_NOTICE "\n"); | 
 | 	printk(KERN_NOTICE "Format %02x  Vector: %04x  PC: %08lx  Status: %04x    %s\n", | 
 | 	       regs->format, regs->vector, regs->pc, regs->sr, print_tainted()); | 
 | 	printk(KERN_NOTICE "ORIG_D0: %08lx  D0: %08lx  A2: %08lx  A1: %08lx\n", | 
 | 	       regs->orig_d0, regs->d0, regs->a2, regs->a1); | 
 | 	printk(KERN_NOTICE "A0: %08lx  D5: %08lx  D4: %08lx\n", | 
 | 	       regs->a0, regs->d5, regs->d4); | 
 | 	printk(KERN_NOTICE "D3: %08lx  D2: %08lx  D1: %08lx\n", | 
 | 	       regs->d3, regs->d2, regs->d1); | 
 | 	if (!(regs->sr & PS_S)) | 
 | 		printk(KERN_NOTICE "USP: %08lx\n", rdusp()); | 
 | } | 
 |  | 
 | /* | 
 |  * Create a kernel thread | 
 |  */ | 
 | int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) | 
 | { | 
 | 	int retval; | 
 | 	long clone_arg = flags | CLONE_VM; | 
 | 	mm_segment_t fs; | 
 |  | 
 | 	fs = get_fs(); | 
 | 	set_fs(KERNEL_DS); | 
 |  | 
 | 	__asm__ __volatile__ ( | 
 | 			"movel	%%sp, %%d2\n\t" | 
 | 			"movel	%5, %%d1\n\t" | 
 | 			"movel	%1, %%d0\n\t" | 
 | 			"trap	#0\n\t" | 
 | 			"cmpl	%%sp, %%d2\n\t" | 
 | 			"jeq	1f\n\t" | 
 | 			"movel	%3, %%sp@-\n\t" | 
 | 			"jsr	%4@\n\t" | 
 | 			"movel	%2, %%d0\n\t" | 
 | 			"trap	#0\n" | 
 | 			"1:\n\t" | 
 | 			"movel	%%d0, %0\n" | 
 | 		: "=d" (retval) | 
 | 		: "i" (__NR_clone), | 
 | 		  "i" (__NR_exit), | 
 | 		  "a" (arg), | 
 | 		  "a" (fn), | 
 | 		  "a" (clone_arg) | 
 | 		: "cc", "%d0", "%d1", "%d2"); | 
 |  | 
 | 	set_fs(fs); | 
 | 	return retval; | 
 | } | 
 |  | 
 | void flush_thread(void) | 
 | { | 
 | #ifdef CONFIG_FPU | 
 | 	unsigned long zero = 0; | 
 | #endif | 
 | 	set_fs(USER_DS); | 
 | 	current->thread.fs = __USER_DS; | 
 | #ifdef CONFIG_FPU | 
 | 	if (!FPU_IS_EMU) | 
 | 		asm volatile (".chip 68k/68881\n\t" | 
 | 			      "frestore %0@\n\t" | 
 | 			      ".chip 68k" : : "a" (&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) | 
 | { | 
 | 	/* fork almost works, enough to trick you into looking elsewhere :-( */ | 
 | 	return(-EINVAL); | 
 | } | 
 |  | 
 | 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; | 
 |  | 
 | 	/* syscall2 puts clone_flags in d1 and usp in d2 */ | 
 | 	clone_flags = regs->d1; | 
 | 	newsp = regs->d2; | 
 | 	if (!newsp) | 
 | 		newsp = rdusp(); | 
 |         return do_fork(clone_flags, newsp, regs, 0, NULL, NULL); | 
 | } | 
 |  | 
 | int copy_thread(int nr, unsigned long clone_flags, | 
 | 		unsigned long usp, unsigned long topstk, | 
 | 		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; | 
 | 	/* | 
 | 	 * 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 (p->thread.fpstate[0]) | 
 | 		  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 | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | /* Fill in the fpu structure for a core dump.  */ | 
 |  | 
 | int dump_fpu(struct pt_regs *regs, struct user_m68kfp_struct *fpu) | 
 | { | 
 | #ifdef CONFIG_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 (!fpustate[0]) | 
 | 		return 0; | 
 |  | 
 | 	asm volatile ("fmovem %/fpiar/%/fpcr/%/fpsr,%0" | 
 | 		:: "m" (fpu->fpcntl[0]) | 
 | 		: "memory"); | 
 | 	asm volatile ("fmovemx %/fp0-%/fp7,%0" | 
 | 		:: "m" (fpu->fpregs[0]) | 
 | 		: "memory"); | 
 | #endif | 
 | 	return 1; | 
 | } | 
 |  | 
 | /* | 
 |  *	Generic dumping code. Used for panic and debug. | 
 |  */ | 
 | void dump(struct pt_regs *fp) | 
 | { | 
 | 	unsigned long	*sp; | 
 | 	unsigned char	*tp; | 
 | 	int		i; | 
 |  | 
 | 	printk(KERN_EMERG "\n" KERN_EMERG "CURRENT PROCESS:\n" KERN_EMERG "\n"); | 
 | 	printk(KERN_EMERG "COMM=%s PID=%d\n", current->comm, current->pid); | 
 |  | 
 | 	if (current->mm) { | 
 | 		printk(KERN_EMERG "TEXT=%08x-%08x DATA=%08x-%08x BSS=%08x-%08x\n", | 
 | 			(int) current->mm->start_code, | 
 | 			(int) current->mm->end_code, | 
 | 			(int) current->mm->start_data, | 
 | 			(int) current->mm->end_data, | 
 | 			(int) current->mm->end_data, | 
 | 			(int) current->mm->brk); | 
 | 		printk(KERN_EMERG "USER-STACK=%08x KERNEL-STACK=%08x\n" | 
 | 			KERN_EMERG "\n", | 
 | 			(int) current->mm->start_stack, | 
 | 			(int)(((unsigned long) current) + THREAD_SIZE)); | 
 | 	} | 
 |  | 
 | 	printk(KERN_EMERG "PC: %08lx\n", fp->pc); | 
 | 	printk(KERN_EMERG "SR: %08lx    SP: %08lx\n", (long) fp->sr, (long) fp); | 
 | 	printk(KERN_EMERG "d0: %08lx    d1: %08lx    d2: %08lx    d3: %08lx\n", | 
 | 		fp->d0, fp->d1, fp->d2, fp->d3); | 
 | 	printk(KERN_EMERG "d4: %08lx    d5: %08lx    a0: %08lx    a1: %08lx\n", | 
 | 		fp->d4, fp->d5, fp->a0, fp->a1); | 
 | 	printk(KERN_EMERG "\n" KERN_EMERG "USP: %08x   TRAPFRAME: %08x\n", | 
 | 		(unsigned int) rdusp(), (unsigned int) fp); | 
 |  | 
 | 	printk(KERN_EMERG "\n" KERN_EMERG "CODE:"); | 
 | 	tp = ((unsigned char *) fp->pc) - 0x20; | 
 | 	for (sp = (unsigned long *) tp, i = 0; (i < 0x40);  i += 4) { | 
 | 		if ((i % 0x10) == 0) | 
 | 			printk("\n" KERN_EMERG "%08x: ", (int) (tp + i)); | 
 | 		printk("%08x ", (int) *sp++); | 
 | 	} | 
 | 	printk("\n" KERN_EMERG "\n"); | 
 |  | 
 | 	printk(KERN_EMERG "KERNEL STACK:"); | 
 | 	tp = ((unsigned char *) fp) - 0x40; | 
 | 	for (sp = (unsigned long *) tp, i = 0; (i < 0xc0); i += 4) { | 
 | 		if ((i % 0x10) == 0) | 
 | 			printk("\n" KERN_EMERG "%08x: ", (int) (tp + i)); | 
 | 		printk("%08x ", (int) *sp++); | 
 | 	} | 
 | 	printk("\n" KERN_EMERG "\n"); | 
 |  | 
 | 	printk(KERN_EMERG "USER STACK:"); | 
 | 	tp = (unsigned char *) (rdusp() - 0x10); | 
 | 	for (sp = (unsigned long *) tp, i = 0; (i < 0x80); i += 4) { | 
 | 		if ((i % 0x10) == 0) | 
 | 			printk("\n" KERN_EMERG "%08x: ", (int) (tp + i)); | 
 | 		printk("%08x ", (int) *sp++); | 
 | 	} | 
 | 	printk("\n" KERN_EMERG "\n"); | 
 | } | 
 |  | 
 | /* | 
 |  * sys_execve() executes a new program. | 
 |  */ | 
 | asmlinkage int sys_execve(char *name, char **argv, char **envp) | 
 | { | 
 | 	int error; | 
 | 	char * filename; | 
 | 	struct pt_regs *regs = (struct pt_regs *) &name; | 
 |  | 
 | 	lock_kernel(); | 
 | 	filename = getname(name); | 
 | 	error = PTR_ERR(filename); | 
 | 	if (IS_ERR(filename)) | 
 | 		goto out; | 
 | 	error = do_execve(filename, argv, envp, regs); | 
 | 	putname(filename); | 
 | out: | 
 | 	unlock_kernel(); | 
 | 	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)p; | 
 | 	fp = ((struct switch_stack *)p->thread.ksp)->a6; | 
 | 	do { | 
 | 		if (fp < stack_page+sizeof(struct thread_info) || | 
 | 		    fp >= THREAD_SIZE-8+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; | 
 | } | 
 |  | 
 | /* | 
 |  * Return saved PC of 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; | 
 | } | 
 |  |