432 lines
		
	
	
		
			10 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			432 lines
		
	
	
		
			10 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * arch/sh/kernel/process.c
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|  *
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|  * This file handles the architecture-dependent parts of process handling..
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|  *
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|  *  Copyright (C) 1995  Linus Torvalds
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|  *
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|  *  SuperH version:  Copyright (C) 1999, 2000  Niibe Yutaka & Kaz Kojima
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|  *		     Copyright (C) 2006 Lineo Solutions Inc. support SH4A UBC
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|  *		     Copyright (C) 2002 - 2008  Paul Mundt
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|  *
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|  * This file is subject to the terms and conditions of the GNU General Public
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|  * License.  See the file "COPYING" in the main directory of this archive
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|  * for more details.
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|  */
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| #include <linux/module.h>
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| #include <linux/mm.h>
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| #include <linux/elfcore.h>
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| #include <linux/pm.h>
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| #include <linux/kallsyms.h>
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| #include <linux/kexec.h>
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| #include <linux/kdebug.h>
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| #include <linux/tick.h>
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| #include <linux/reboot.h>
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| #include <linux/fs.h>
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| #include <linux/ftrace.h>
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| #include <linux/preempt.h>
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| #include <asm/uaccess.h>
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| #include <asm/mmu_context.h>
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| #include <asm/pgalloc.h>
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| #include <asm/system.h>
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| #include <asm/ubc.h>
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| #include <asm/fpu.h>
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| #include <asm/syscalls.h>
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| #include <asm/watchdog.h>
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| 
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| int ubc_usercnt = 0;
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| 
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| #ifdef CONFIG_32BIT
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| static void watchdog_trigger_immediate(void)
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| {
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| 	sh_wdt_write_cnt(0xFF);
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| 	sh_wdt_write_csr(0xC2);
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| }
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| 
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| void machine_restart(char * __unused)
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| {
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| 	local_irq_disable();
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| 
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| 	/* Use watchdog timer to trigger reset */
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| 	watchdog_trigger_immediate();
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| 
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| 	while (1)
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| 		cpu_sleep();
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| }
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| #else
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| void machine_restart(char * __unused)
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| {
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| 	/* SR.BL=1 and invoke address error to let CPU reset (manual reset) */
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| 	asm volatile("ldc %0, sr\n\t"
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| 		     "mov.l @%1, %0" : : "r" (0x10000000), "r" (0x80000001));
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| }
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| #endif
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| 
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| void machine_halt(void)
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| {
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| 	local_irq_disable();
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| 
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| 	while (1)
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| 		cpu_sleep();
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| }
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| 
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| void machine_power_off(void)
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| {
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| 	if (pm_power_off)
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| 		pm_power_off();
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| }
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| 
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| void show_regs(struct pt_regs * regs)
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| {
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| 	printk("\n");
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| 	printk("Pid : %d, Comm: \t\t%s\n", task_pid_nr(current), current->comm);
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| 	printk("CPU : %d        \t\t%s  (%s %.*s)\n\n",
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| 	       smp_processor_id(), print_tainted(), init_utsname()->release,
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| 	       (int)strcspn(init_utsname()->version, " "),
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| 	       init_utsname()->version);
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| 
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| 	print_symbol("PC is at %s\n", instruction_pointer(regs));
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| 	print_symbol("PR is at %s\n", regs->pr);
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| 
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| 	printk("PC  : %08lx SP  : %08lx SR  : %08lx ",
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| 	       regs->pc, regs->regs[15], regs->sr);
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| #ifdef CONFIG_MMU
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| 	printk("TEA : %08x\n", ctrl_inl(MMU_TEA));
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| #else
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| 	printk("\n");
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| #endif
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| 
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| 	printk("R0  : %08lx R1  : %08lx R2  : %08lx R3  : %08lx\n",
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| 	       regs->regs[0],regs->regs[1],
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| 	       regs->regs[2],regs->regs[3]);
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| 	printk("R4  : %08lx R5  : %08lx R6  : %08lx R7  : %08lx\n",
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| 	       regs->regs[4],regs->regs[5],
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| 	       regs->regs[6],regs->regs[7]);
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| 	printk("R8  : %08lx R9  : %08lx R10 : %08lx R11 : %08lx\n",
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| 	       regs->regs[8],regs->regs[9],
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| 	       regs->regs[10],regs->regs[11]);
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| 	printk("R12 : %08lx R13 : %08lx R14 : %08lx\n",
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| 	       regs->regs[12],regs->regs[13],
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| 	       regs->regs[14]);
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| 	printk("MACH: %08lx MACL: %08lx GBR : %08lx PR  : %08lx\n",
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| 	       regs->mach, regs->macl, regs->gbr, regs->pr);
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| 
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| 	show_trace(NULL, (unsigned long *)regs->regs[15], regs);
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| 	show_code(regs);
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| }
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| 
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| /*
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|  * Create a kernel thread
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|  */
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| ATTRIB_NORET void kernel_thread_helper(void *arg, int (*fn)(void *))
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| {
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| 	do_exit(fn(arg));
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| }
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| 
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| /* Don't use this in BL=1(cli).  Or else, CPU resets! */
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| int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
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| {
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| 	struct pt_regs regs;
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| 	int pid;
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| 
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| 	memset(®s, 0, sizeof(regs));
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| 	regs.regs[4] = (unsigned long)arg;
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| 	regs.regs[5] = (unsigned long)fn;
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| 
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| 	regs.pc = (unsigned long)kernel_thread_helper;
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| 	regs.sr = (1 << 30);
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| 
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| 	/* Ok, create the new process.. */
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| 	pid = do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0,
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| 		      ®s, 0, NULL, NULL);
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| 
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| 	return pid;
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| }
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| 
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| /*
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|  * Free current thread data structures etc..
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|  */
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| void exit_thread(void)
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| {
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| 	if (current->thread.ubc_pc) {
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| 		current->thread.ubc_pc = 0;
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| 		ubc_usercnt -= 1;
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| 	}
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| }
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| 
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| void flush_thread(void)
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| {
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| #if defined(CONFIG_SH_FPU)
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| 	struct task_struct *tsk = current;
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| 	/* Forget lazy FPU state */
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| 	clear_fpu(tsk, task_pt_regs(tsk));
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| 	clear_used_math();
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| #endif
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| }
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| 
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| void release_thread(struct task_struct *dead_task)
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| {
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| 	/* do nothing */
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| }
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| 
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| /* Fill in the fpu structure for a core dump.. */
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| int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
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| {
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| 	int fpvalid = 0;
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| 
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| #if defined(CONFIG_SH_FPU)
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| 	struct task_struct *tsk = current;
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| 
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| 	fpvalid = !!tsk_used_math(tsk);
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| 	if (fpvalid)
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| 		fpvalid = !fpregs_get(tsk, NULL, 0,
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| 				      sizeof(struct user_fpu_struct),
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| 				      fpu, NULL);
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| #endif
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| 
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| 	return fpvalid;
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| }
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| 
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| asmlinkage void ret_from_fork(void);
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| 
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| int copy_thread(unsigned long clone_flags, unsigned long usp,
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| 		unsigned long unused,
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| 		struct task_struct *p, struct pt_regs *regs)
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| {
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| 	struct thread_info *ti = task_thread_info(p);
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| 	struct pt_regs *childregs;
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| #if defined(CONFIG_SH_FPU) || defined(CONFIG_SH_DSP)
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| 	struct task_struct *tsk = current;
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| #endif
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| 
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| #if defined(CONFIG_SH_FPU)
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| 	unlazy_fpu(tsk, regs);
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| 	p->thread.fpu = tsk->thread.fpu;
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| 	copy_to_stopped_child_used_math(p);
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| #endif
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| 
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| #if defined(CONFIG_SH_DSP)
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| 	if (is_dsp_enabled(tsk)) {
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| 		/* We can use the __save_dsp or just copy the struct:
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| 		 * __save_dsp(p);
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| 		 * p->thread.dsp_status.status |= SR_DSP
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| 		 */
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| 		p->thread.dsp_status = tsk->thread.dsp_status;
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| 	}
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| #endif
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| 
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| 	childregs = task_pt_regs(p);
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| 	*childregs = *regs;
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| 
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| 	if (user_mode(regs)) {
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| 		childregs->regs[15] = usp;
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| 		ti->addr_limit = USER_DS;
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| 	} else {
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| 		childregs->regs[15] = (unsigned long)childregs;
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| 		ti->addr_limit = KERNEL_DS;
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| 	}
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| 
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| 	if (clone_flags & CLONE_SETTLS)
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| 		childregs->gbr = childregs->regs[0];
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| 
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| 	childregs->regs[0] = 0; /* Set return value for child */
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| 
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| 	p->thread.sp = (unsigned long) childregs;
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| 	p->thread.pc = (unsigned long) ret_from_fork;
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| 
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| 	p->thread.ubc_pc = 0;
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| 
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| 	return 0;
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| }
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| 
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| /* Tracing by user break controller.  */
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| static void ubc_set_tracing(int asid, unsigned long pc)
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| {
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| #if defined(CONFIG_CPU_SH4A)
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| 	unsigned long val;
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| 
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| 	val = (UBC_CBR_ID_INST | UBC_CBR_RW_READ | UBC_CBR_CE);
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| 	val |= (UBC_CBR_AIE | UBC_CBR_AIV_SET(asid));
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| 
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| 	ctrl_outl(val, UBC_CBR0);
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| 	ctrl_outl(pc,  UBC_CAR0);
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| 	ctrl_outl(0x0, UBC_CAMR0);
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| 	ctrl_outl(0x0, UBC_CBCR);
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| 
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| 	val = (UBC_CRR_RES | UBC_CRR_PCB | UBC_CRR_BIE);
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| 	ctrl_outl(val, UBC_CRR0);
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| 
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| 	/* Read UBC register that we wrote last, for checking update */
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| 	val = ctrl_inl(UBC_CRR0);
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| 
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| #else	/* CONFIG_CPU_SH4A */
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| 	ctrl_outl(pc, UBC_BARA);
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| 
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| #ifdef CONFIG_MMU
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| 	ctrl_outb(asid, UBC_BASRA);
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| #endif
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| 
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| 	ctrl_outl(0, UBC_BAMRA);
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| 
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| 	if (current_cpu_data.type == CPU_SH7729 ||
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| 	    current_cpu_data.type == CPU_SH7710 ||
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| 	    current_cpu_data.type == CPU_SH7712 ||
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| 	    current_cpu_data.type == CPU_SH7203){
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| 		ctrl_outw(BBR_INST | BBR_READ | BBR_CPU, UBC_BBRA);
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| 		ctrl_outl(BRCR_PCBA | BRCR_PCTE, UBC_BRCR);
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| 	} else {
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| 		ctrl_outw(BBR_INST | BBR_READ, UBC_BBRA);
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| 		ctrl_outw(BRCR_PCBA, UBC_BRCR);
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| 	}
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| #endif	/* CONFIG_CPU_SH4A */
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| }
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| 
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| /*
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|  *	switch_to(x,y) should switch tasks from x to y.
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|  *
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|  */
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| __notrace_funcgraph struct task_struct *
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| __switch_to(struct task_struct *prev, struct task_struct *next)
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| {
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| #if defined(CONFIG_SH_FPU)
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| 	unlazy_fpu(prev, task_pt_regs(prev));
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| #endif
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| 
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| #ifdef CONFIG_MMU
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| 	/*
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| 	 * Restore the kernel mode register
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| 	 *	k7 (r7_bank1)
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| 	 */
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| 	asm volatile("ldc	%0, r7_bank"
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| 		     : /* no output */
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| 		     : "r" (task_thread_info(next)));
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| #endif
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| 
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| 	/* If no tasks are using the UBC, we're done */
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| 	if (ubc_usercnt == 0)
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| 		/* If no tasks are using the UBC, we're done */;
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| 	else if (next->thread.ubc_pc && next->mm) {
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| 		int asid = 0;
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| #ifdef CONFIG_MMU
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| 		asid |= cpu_asid(smp_processor_id(), next->mm);
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| #endif
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| 		ubc_set_tracing(asid, next->thread.ubc_pc);
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| 	} else {
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| #if defined(CONFIG_CPU_SH4A)
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| 		ctrl_outl(UBC_CBR_INIT, UBC_CBR0);
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| 		ctrl_outl(UBC_CRR_INIT, UBC_CRR0);
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| #else
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| 		ctrl_outw(0, UBC_BBRA);
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| 		ctrl_outw(0, UBC_BBRB);
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| #endif
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| 	}
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| 
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| 	return prev;
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| }
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| 
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| asmlinkage int sys_fork(unsigned long r4, unsigned long r5,
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| 			unsigned long r6, unsigned long r7,
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| 			struct pt_regs __regs)
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| {
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| #ifdef CONFIG_MMU
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| 	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
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| 	return do_fork(SIGCHLD, regs->regs[15], regs, 0, NULL, NULL);
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| #else
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| 	/* fork almost works, enough to trick you into looking elsewhere :-( */
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| 	return -EINVAL;
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| #endif
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| }
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| 
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| asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
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| 			 unsigned long parent_tidptr,
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| 			 unsigned long child_tidptr,
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| 			 struct pt_regs __regs)
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| {
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| 	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
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| 	if (!newsp)
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| 		newsp = regs->regs[15];
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| 	return do_fork(clone_flags, newsp, regs, 0,
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| 			(int __user *)parent_tidptr,
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| 			(int __user *)child_tidptr);
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| }
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| 
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| /*
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|  * This is trivial, and on the face of it looks like it
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|  * could equally well be done in user mode.
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|  *
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|  * Not so, for quite unobvious reasons - register pressure.
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|  * In user mode vfork() cannot have a stack frame, and if
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|  * done by calling the "clone()" system call directly, you
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|  * do not have enough call-clobbered registers to hold all
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|  * the information you need.
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|  */
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| asmlinkage int sys_vfork(unsigned long r4, unsigned long r5,
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| 			 unsigned long r6, unsigned long r7,
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| 			 struct pt_regs __regs)
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| {
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| 	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
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| 	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->regs[15], regs,
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| 		       0, NULL, NULL);
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| }
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| 
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| /*
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|  * sys_execve() executes a new program.
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|  */
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| asmlinkage int sys_execve(char __user *ufilename, char __user * __user *uargv,
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| 			  char __user * __user *uenvp, unsigned long r7,
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| 			  struct pt_regs __regs)
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| {
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| 	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
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| 	int error;
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| 	char *filename;
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| 
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| 	filename = getname(ufilename);
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| 	error = PTR_ERR(filename);
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| 	if (IS_ERR(filename))
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| 		goto out;
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| 
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| 	error = do_execve(filename, uargv, uenvp, regs);
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| 	putname(filename);
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| out:
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| 	return error;
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| }
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| 
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| unsigned long get_wchan(struct task_struct *p)
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| {
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| 	unsigned long pc;
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| 
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| 	if (!p || p == current || p->state == TASK_RUNNING)
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| 		return 0;
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| 
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| 	/*
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| 	 * The same comment as on the Alpha applies here, too ...
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| 	 */
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| 	pc = thread_saved_pc(p);
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| 
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| #ifdef CONFIG_FRAME_POINTER
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| 	if (in_sched_functions(pc)) {
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| 		unsigned long schedule_frame = (unsigned long)p->thread.sp;
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| 		return ((unsigned long *)schedule_frame)[21];
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| 	}
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| #endif
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| 
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| 	return pc;
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| }
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| 
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| asmlinkage void break_point_trap(void)
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| {
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| 	/* Clear tracing.  */
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| #if defined(CONFIG_CPU_SH4A)
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| 	ctrl_outl(UBC_CBR_INIT, UBC_CBR0);
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| 	ctrl_outl(UBC_CRR_INIT, UBC_CRR0);
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| #else
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| 	ctrl_outw(0, UBC_BBRA);
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| 	ctrl_outw(0, UBC_BBRB);
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| 	ctrl_outl(0, UBC_BRCR);
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| #endif
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| 	current->thread.ubc_pc = 0;
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| 	ubc_usercnt -= 1;
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| 
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| 	force_sig(SIGTRAP, current);
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| }
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