arch/s390/kernel/process.c - android_kernel_htc_msm8960 - Gitiles

 /*
  *  arch/s390/kernel/process.c
  *
  *  S390 version
  *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
  *               Hartmut Penner (hp@de.ibm.com),
  *               Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
  *
  *  Derived from "arch/i386/kernel/process.c"
  *    Copyright (C) 1995, Linus Torvalds
  */

 /*
  * This file handles the architecture-dependent parts of process handling..
  */

 #include <linux/config.h>
 #include <linux/compiler.h>
 #include <linux/cpu.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/vmalloc.h>
 #include <linux/user.h>
 #include <linux/a.out.h>
 #include <linux/interrupt.h>
 #include <linux/delay.h>
 #include <linux/reboot.h>
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/notifier.h>

 #include <asm/uaccess.h>
 #include <asm/pgtable.h>
 #include <asm/system.h>
 #include <asm/io.h>
 #include <asm/processor.h>
 #include <asm/irq.h>
 #include <asm/timer.h>

 asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");

 /*
  * Return saved PC of a blocked thread. used in kernel/sched.
  * resume in entry.S does not create a new stack frame, it
  * just stores the registers %r6-%r15 to the frame given by
  * schedule. We want to return the address of the caller of
  * schedule, so we have to walk the backchain one time to
  * find the frame schedule() store its return address.
  */
 unsigned long thread_saved_pc(struct task_struct *tsk)
 {
 	struct stack_frame *sf;

 	sf = (struct stack_frame *) tsk->thread.ksp;
 	sf = (struct stack_frame *) sf->back_chain;
 	return sf->gprs[8];
 }

 /*
  * Need to know about CPUs going idle?
  */
 static struct notifier_block *idle_chain;

 int register_idle_notifier(struct notifier_block *nb)
 {
 	return notifier_chain_register(&idle_chain, nb);
 }
 EXPORT_SYMBOL(register_idle_notifier);

 int unregister_idle_notifier(struct notifier_block *nb)
 {
 	return notifier_chain_unregister(&idle_chain, nb);
 }
 EXPORT_SYMBOL(unregister_idle_notifier);

 void do_monitor_call(struct pt_regs *regs, long interruption_code)
 {
 	/* disable monitor call class 0 */
 	__ctl_clear_bit(8, 15);

 	notifier_call_chain(&idle_chain, CPU_NOT_IDLE,
 			    (void *)(long) smp_processor_id());
 }

 extern void s390_handle_mcck(void);
 /*
  * The idle loop on a S390...
  */
 void default_idle(void)
 {
 	int cpu, rc;

 	local_irq_disable();
         if (need_resched()) {
 		local_irq_enable();
                 schedule();
                 return;
         }

 	/* CPU is going idle. */
 	cpu = smp_processor_id();
 	rc = notifier_call_chain(&idle_chain, CPU_IDLE, (void *)(long) cpu);
 	if (rc != NOTIFY_OK && rc != NOTIFY_DONE)
 		BUG();
 	if (rc != NOTIFY_OK) {
 		local_irq_enable();
 		return;
 	}

 	/* enable monitor call class 0 */
 	__ctl_set_bit(8, 15);

 #ifdef CONFIG_HOTPLUG_CPU
 	if (cpu_is_offline(smp_processor_id()))
 		cpu_die();
 #endif

 	local_mcck_disable();
 	if (test_thread_flag(TIF_MCCK_PENDING)) {
 		local_mcck_enable();
 		local_irq_enable();
 		s390_handle_mcck();
 		return;
 	}

 	/* Wait for external, I/O or machine check interrupt. */
 	__load_psw_mask(PSW_KERNEL_BITS | PSW_MASK_WAIT |
 			PSW_MASK_IO | PSW_MASK_EXT);
 }

 void cpu_idle(void)
 {
 	for (;;)
 		default_idle();
 }

 void show_regs(struct pt_regs *regs)
 {
 	struct task_struct *tsk = current;

         printk("CPU:    %d    %s\n", tsk->thread_info->cpu, print_tainted());
         printk("Process %s (pid: %d, task: %p, ksp: %p)\n",
 	       current->comm, current->pid, (void *) tsk,
 	       (void *) tsk->thread.ksp);

 	show_registers(regs);
 	/* Show stack backtrace if pt_regs is from kernel mode */
 	if (!(regs->psw.mask & PSW_MASK_PSTATE))
 		show_trace(0,(unsigned long *) regs->gprs[15]);
 }

 extern void kernel_thread_starter(void);

 __asm__(".align 4\n"
 	"kernel_thread_starter:\n"
 	"    la    2,0(10)\n"
 	"    basr  14,9\n"
 	"    la    2,0\n"
 	"    br    11\n");

 int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
 {
 	struct pt_regs regs;

 	memset(&regs, 0, sizeof(regs));
 	regs.psw.mask = PSW_KERNEL_BITS | PSW_MASK_IO | PSW_MASK_EXT;
 	regs.psw.addr = (unsigned long) kernel_thread_starter | PSW_ADDR_AMODE;
 	regs.gprs[9] = (unsigned long) fn;
 	regs.gprs[10] = (unsigned long) arg;
 	regs.gprs[11] = (unsigned long) do_exit;
 	regs.orig_gpr2 = -1;

 	/* Ok, create the new process.. */
 	return do_fork(flags | CLONE_VM | CLONE_UNTRACED,
 		       0, &regs, 0, NULL, NULL);
 }

 /*
  * Free current thread data structures etc..
  */
 void exit_thread(void)
 {
 }

 void flush_thread(void)
 {
 	clear_used_math();
 	clear_tsk_thread_flag(current, TIF_USEDFPU);
 }

 void release_thread(struct task_struct *dead_task)
 {
 }

 int copy_thread(int nr, unsigned long clone_flags, unsigned long new_stackp,
 	unsigned long unused,
         struct task_struct * p, struct pt_regs * regs)
 {
         struct fake_frame
           {
 	    struct stack_frame sf;
             struct pt_regs childregs;
           } *frame;

         frame = ((struct fake_frame *)
 		 (THREAD_SIZE + (unsigned long) p->thread_info)) - 1;
         p->thread.ksp = (unsigned long) frame;
 	/* Store access registers to kernel stack of new process. */
         frame->childregs = *regs;
 	frame->childregs.gprs[2] = 0;	/* child returns 0 on fork. */
         frame->childregs.gprs[15] = new_stackp;
         frame->sf.back_chain = 0;

         /* new return point is ret_from_fork */
         frame->sf.gprs[8] = (unsigned long) ret_from_fork;

         /* fake return stack for resume(), don't go back to schedule */
         frame->sf.gprs[9] = (unsigned long) frame;

 	/* Save access registers to new thread structure. */
 	save_access_regs(&p->thread.acrs[0]);

 #ifndef CONFIG_ARCH_S390X
         /*
 	 * save fprs to current->thread.fp_regs to merge them with
 	 * the emulated registers and then copy the result to the child.
 	 */
 	save_fp_regs(&current->thread.fp_regs);
 	memcpy(&p->thread.fp_regs, &current->thread.fp_regs,
 	       sizeof(s390_fp_regs));
         p->thread.user_seg = __pa((unsigned long) p->mm->pgd) | _SEGMENT_TABLE;
 	/* Set a new TLS ?  */
 	if (clone_flags & CLONE_SETTLS)
 		p->thread.acrs[0] = regs->gprs[6];
 #else /* CONFIG_ARCH_S390X */
 	/* Save the fpu registers to new thread structure. */
 	save_fp_regs(&p->thread.fp_regs);
         p->thread.user_seg = __pa((unsigned long) p->mm->pgd) | _REGION_TABLE;
 	/* Set a new TLS ?  */
 	if (clone_flags & CLONE_SETTLS) {
 		if (test_thread_flag(TIF_31BIT)) {
 			p->thread.acrs[0] = (unsigned int) regs->gprs[6];
 		} else {
 			p->thread.acrs[0] = (unsigned int)(regs->gprs[6] >> 32);
 			p->thread.acrs[1] = (unsigned int) regs->gprs[6];
 		}
 	}
 #endif /* CONFIG_ARCH_S390X */
 	/* start new process with ar4 pointing to the correct address space */
 	p->thread.mm_segment = get_fs();
         /* Don't copy debug registers */
         memset(&p->thread.per_info,0,sizeof(p->thread.per_info));

         return 0;
 }

 asmlinkage long sys_fork(struct pt_regs regs)
 {
 	return do_fork(SIGCHLD, regs.gprs[15], &regs, 0, NULL, NULL);
 }

 asmlinkage long sys_clone(struct pt_regs regs)
 {
         unsigned long clone_flags;
         unsigned long newsp;
 	int __user *parent_tidptr, *child_tidptr;

         clone_flags = regs.gprs[3];
         newsp = regs.orig_gpr2;
 	parent_tidptr = (int __user *) regs.gprs[4];
 	child_tidptr = (int __user *) regs.gprs[5];
         if (!newsp)
                 newsp = regs.gprs[15];
         return do_fork(clone_flags, newsp, &regs, 0,
 		       parent_tidptr, child_tidptr);
 }

 /*
  * This is trivial, and on the face of it looks like it
  * could equally well be done in user mode.
  *
  * Not so, for quite unobvious reasons - register pressure.
  * In user mode vfork() cannot have a stack frame, and if
  * done by calling the "clone()" system call directly, you
  * do not have enough call-clobbered registers to hold all
  * the information you need.
  */
 asmlinkage long sys_vfork(struct pt_regs regs)
 {
 	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD,
 		       regs.gprs[15], &regs, 0, NULL, NULL);
 }

 /*
  * sys_execve() executes a new program.
  */
 asmlinkage long sys_execve(struct pt_regs regs)
 {
         int error;
         char * filename;

         filename = getname((char __user *) regs.orig_gpr2);
         error = PTR_ERR(filename);
         if (IS_ERR(filename))
                 goto out;
         error = do_execve(filename, (char __user * __user *) regs.gprs[3],
 			  (char __user * __user *) regs.gprs[4], &regs);
 	if (error == 0) {
 		task_lock(current);
 		current->ptrace &= ~PT_DTRACE;
 		task_unlock(current);
 		current->thread.fp_regs.fpc = 0;
 		if (MACHINE_HAS_IEEE)
 			asm volatile("sfpc %0,%0" : : "d" (0));
 	}
         putname(filename);
 out:
         return error;
 }


 /*
  * fill in the FPU structure for a core dump.
  */
 int dump_fpu (struct pt_regs * regs, s390_fp_regs *fpregs)
 {
 #ifndef CONFIG_ARCH_S390X
         /*
 	 * save fprs to current->thread.fp_regs to merge them with
 	 * the emulated registers and then copy the result to the dump.
 	 */
 	save_fp_regs(&current->thread.fp_regs);
 	memcpy(fpregs, &current->thread.fp_regs, sizeof(s390_fp_regs));
 #else /* CONFIG_ARCH_S390X */
 	save_fp_regs(fpregs);
 #endif /* CONFIG_ARCH_S390X */
 	return 1;
 }

 /*
  * fill in the user structure for a core dump..
  */
 void dump_thread(struct pt_regs * regs, struct user * dump)
 {

 /* changed the size calculations - should hopefully work better. lbt */
 	dump->magic = CMAGIC;
 	dump->start_code = 0;
 	dump->start_stack = regs->gprs[15] & ~(PAGE_SIZE - 1);
 	dump->u_tsize = current->mm->end_code >> PAGE_SHIFT;
 	dump->u_dsize = (current->mm->brk + PAGE_SIZE - 1) >> PAGE_SHIFT;
 	dump->u_dsize -= dump->u_tsize;
 	dump->u_ssize = 0;
 	if (dump->start_stack < TASK_SIZE)
 		dump->u_ssize = (TASK_SIZE - dump->start_stack) >> PAGE_SHIFT;
 	memcpy(&dump->regs, regs, sizeof(s390_regs));
 	dump_fpu (regs, &dump->regs.fp_regs);
 	dump->regs.per_info = current->thread.per_info;
 }

 unsigned long get_wchan(struct task_struct *p)
 {
 	struct stack_frame *sf, *low, *high;
 	unsigned long return_address;
 	int count;

 	if (!p || p == current || p->state == TASK_RUNNING || !p->thread_info)
 		return 0;
 	low = (struct stack_frame *) p->thread_info;
 	high = (struct stack_frame *)
 		((unsigned long) p->thread_info + THREAD_SIZE) - 1;
 	sf = (struct stack_frame *) (p->thread.ksp & PSW_ADDR_INSN);
 	if (sf <= low || sf > high)
 		return 0;
 	for (count = 0; count < 16; count++) {
 		sf = (struct stack_frame *) (sf->back_chain & PSW_ADDR_INSN);
 		if (sf <= low || sf > high)
 			return 0;
 		return_address = sf->gprs[8] & PSW_ADDR_INSN;
 		if (!in_sched_functions(return_address))
 			return return_address;
 	}
 	return 0;
 }
	/*
	* arch/s390/kernel/process.c
	*
	* S390 version
	* Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
	* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
	* Hartmut Penner (hp@de.ibm.com),
	* Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
	*
	* Derived from "arch/i386/kernel/process.c"
	* Copyright (C) 1995, Linus Torvalds
	*/

	/*
	* This file handles the architecture-dependent parts of process handling..
	*/

	#include <linux/config.h>
	#include <linux/compiler.h>
	#include <linux/cpu.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/vmalloc.h>
	#include <linux/user.h>
	#include <linux/a.out.h>
	#include <linux/interrupt.h>
	#include <linux/delay.h>
	#include <linux/reboot.h>
	#include <linux/init.h>
	#include <linux/module.h>
	#include <linux/notifier.h>

	#include <asm/uaccess.h>
	#include <asm/pgtable.h>
	#include <asm/system.h>
	#include <asm/io.h>
	#include <asm/processor.h>
	#include <asm/irq.h>
	#include <asm/timer.h>

	asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");

	/*
	* Return saved PC of a blocked thread. used in kernel/sched.
	* resume in entry.S does not create a new stack frame, it
	* just stores the registers %r6-%r15 to the frame given by
	* schedule. We want to return the address of the caller of
	* schedule, so we have to walk the backchain one time to
	* find the frame schedule() store its return address.
	*/
	unsigned long thread_saved_pc(struct task_struct *tsk)
	{
	struct stack_frame *sf;

	sf = (struct stack_frame *) tsk->thread.ksp;
	sf = (struct stack_frame *) sf->back_chain;
	return sf->gprs[8];
	}

	/*
	* Need to know about CPUs going idle?
	*/
	static struct notifier_block *idle_chain;

	int register_idle_notifier(struct notifier_block *nb)
	{
	return notifier_chain_register(&idle_chain, nb);
	}
	EXPORT_SYMBOL(register_idle_notifier);

	int unregister_idle_notifier(struct notifier_block *nb)
	{
	return notifier_chain_unregister(&idle_chain, nb);
	}
	EXPORT_SYMBOL(unregister_idle_notifier);

	void do_monitor_call(struct pt_regs *regs, long interruption_code)
	{
	/* disable monitor call class 0 */
	__ctl_clear_bit(8, 15);

	notifier_call_chain(&idle_chain, CPU_NOT_IDLE,
	(void *)(long) smp_processor_id());
	}

	extern void s390_handle_mcck(void);
	/*
	* The idle loop on a S390...
	*/
	void default_idle(void)
	{
	int cpu, rc;

	local_irq_disable();
	if (need_resched()) {
	local_irq_enable();
	schedule();
	return;
	}

	/* CPU is going idle. */
	cpu = smp_processor_id();
	rc = notifier_call_chain(&idle_chain, CPU_IDLE, (void *)(long) cpu);
	if (rc != NOTIFY_OK && rc != NOTIFY_DONE)
	BUG();
	if (rc != NOTIFY_OK) {
	local_irq_enable();
	return;
	}

	/* enable monitor call class 0 */
	__ctl_set_bit(8, 15);

	#ifdef CONFIG_HOTPLUG_CPU
	if (cpu_is_offline(smp_processor_id()))
	cpu_die();
	#endif

	local_mcck_disable();
	if (test_thread_flag(TIF_MCCK_PENDING)) {
	local_mcck_enable();
	local_irq_enable();
	s390_handle_mcck();
	return;
	}

	/* Wait for external, I/O or machine check interrupt. */
	__load_psw_mask(PSW_KERNEL_BITS \| PSW_MASK_WAIT \|
	PSW_MASK_IO \| PSW_MASK_EXT);
	}

	void cpu_idle(void)
	{
	for (;;)
	default_idle();
	}

	void show_regs(struct pt_regs *regs)
	{
	struct task_struct *tsk = current;

	printk("CPU: %d %s\n", tsk->thread_info->cpu, print_tainted());
	printk("Process %s (pid: %d, task: %p, ksp: %p)\n",
	current->comm, current->pid, (void *) tsk,
	(void *) tsk->thread.ksp);

	show_registers(regs);
	/* Show stack backtrace if pt_regs is from kernel mode */
	if (!(regs->psw.mask & PSW_MASK_PSTATE))
	show_trace(0,(unsigned long *) regs->gprs[15]);
	}

	extern void kernel_thread_starter(void);

	__asm__(".align 4\n"
	"kernel_thread_starter:\n"
	" la 2,0(10)\n"
	" basr 14,9\n"
	" la 2,0\n"
	" br 11\n");

	int kernel_thread(int (fn)(void ), void * arg, unsigned long flags)
	{
	struct pt_regs regs;

	memset(&regs, 0, sizeof(regs));
	regs.psw.mask = PSW_KERNEL_BITS \| PSW_MASK_IO \| PSW_MASK_EXT;
	regs.psw.addr = (unsigned long) kernel_thread_starter \| PSW_ADDR_AMODE;
	regs.gprs[9] = (unsigned long) fn;
	regs.gprs[10] = (unsigned long) arg;
	regs.gprs[11] = (unsigned long) do_exit;
	regs.orig_gpr2 = -1;

	/* Ok, create the new process.. */
	return do_fork(flags \| CLONE_VM \| CLONE_UNTRACED,
	0, &regs, 0, NULL, NULL);
	}

	/*
	* Free current thread data structures etc..
	*/
	void exit_thread(void)
	{
	}

	void flush_thread(void)
	{
	clear_used_math();
	clear_tsk_thread_flag(current, TIF_USEDFPU);
	}

	void release_thread(struct task_struct *dead_task)
	{
	}

	int copy_thread(int nr, unsigned long clone_flags, unsigned long new_stackp,
	unsigned long unused,
	struct task_struct * p, struct pt_regs * regs)
	{
	struct fake_frame
	{
	struct stack_frame sf;
	struct pt_regs childregs;
	} *frame;

	frame = ((struct fake_frame *)
	(THREAD_SIZE + (unsigned long) p->thread_info)) - 1;
	p->thread.ksp = (unsigned long) frame;
	/* Store access registers to kernel stack of new process. */
	frame->childregs = *regs;
	frame->childregs.gprs[2] = 0; /* child returns 0 on fork. */
	frame->childregs.gprs[15] = new_stackp;
	frame->sf.back_chain = 0;

	/* new return point is ret_from_fork */
	frame->sf.gprs[8] = (unsigned long) ret_from_fork;

	/* fake return stack for resume(), don't go back to schedule */
	frame->sf.gprs[9] = (unsigned long) frame;

	/* Save access registers to new thread structure. */
	save_access_regs(&p->thread.acrs[0]);

	#ifndef CONFIG_ARCH_S390X
	/*
	* save fprs to current->thread.fp_regs to merge them with
	* the emulated registers and then copy the result to the child.
	*/
	save_fp_regs(&current->thread.fp_regs);
	memcpy(&p->thread.fp_regs, &current->thread.fp_regs,
	sizeof(s390_fp_regs));
	p->thread.user_seg = __pa((unsigned long) p->mm->pgd) \| _SEGMENT_TABLE;
	/* Set a new TLS ? */
	if (clone_flags & CLONE_SETTLS)
	p->thread.acrs[0] = regs->gprs[6];
	#else /* CONFIG_ARCH_S390X */
	/* Save the fpu registers to new thread structure. */
	save_fp_regs(&p->thread.fp_regs);
	p->thread.user_seg = __pa((unsigned long) p->mm->pgd) \| _REGION_TABLE;
	/* Set a new TLS ? */
	if (clone_flags & CLONE_SETTLS) {
	if (test_thread_flag(TIF_31BIT)) {
	p->thread.acrs[0] = (unsigned int) regs->gprs[6];
	} else {
	p->thread.acrs[0] = (unsigned int)(regs->gprs[6] >> 32);
	p->thread.acrs[1] = (unsigned int) regs->gprs[6];
	}
	}
	#endif /* CONFIG_ARCH_S390X */
	/* start new process with ar4 pointing to the correct address space */
	p->thread.mm_segment = get_fs();
	/* Don't copy debug registers */
	memset(&p->thread.per_info,0,sizeof(p->thread.per_info));

	return 0;
	}

	asmlinkage long sys_fork(struct pt_regs regs)
	{
	return do_fork(SIGCHLD, regs.gprs[15], &regs, 0, NULL, NULL);
	}

	asmlinkage long sys_clone(struct pt_regs regs)
	{
	unsigned long clone_flags;
	unsigned long newsp;
	int __user parent_tidptr, child_tidptr;

	clone_flags = regs.gprs[3];
	newsp = regs.orig_gpr2;
	parent_tidptr = (int __user *) regs.gprs[4];
	child_tidptr = (int __user *) regs.gprs[5];
	if (!newsp)
	newsp = regs.gprs[15];
	return do_fork(clone_flags, newsp, &regs, 0,
	parent_tidptr, child_tidptr);
	}

	/*
	* This is trivial, and on the face of it looks like it
	* could equally well be done in user mode.
	*
	* Not so, for quite unobvious reasons - register pressure.
	* In user mode vfork() cannot have a stack frame, and if
	* done by calling the "clone()" system call directly, you
	* do not have enough call-clobbered registers to hold all
	* the information you need.
	*/
	asmlinkage long sys_vfork(struct pt_regs regs)
	{
	return do_fork(CLONE_VFORK \| CLONE_VM \| SIGCHLD,
	regs.gprs[15], &regs, 0, NULL, NULL);
	}

	/*
	* sys_execve() executes a new program.
	*/
	asmlinkage long sys_execve(struct pt_regs regs)
	{
	int error;
	char * filename;

	filename = getname((char __user *) regs.orig_gpr2);
	error = PTR_ERR(filename);
	if (IS_ERR(filename))
	goto out;
	error = do_execve(filename, (char __user * __user *) regs.gprs[3],
	(char __user * __user *) regs.gprs[4], &regs);
	if (error == 0) {
	task_lock(current);
	current->ptrace &= ~PT_DTRACE;
	task_unlock(current);
	current->thread.fp_regs.fpc = 0;
	if (MACHINE_HAS_IEEE)
	asm volatile("sfpc %0,%0" : : "d" (0));
	}
	putname(filename);
	out:
	return error;
	}


	/*
	* fill in the FPU structure for a core dump.
	*/
	int dump_fpu (struct pt_regs * regs, s390_fp_regs *fpregs)
	{
	#ifndef CONFIG_ARCH_S390X
	/*
	* save fprs to current->thread.fp_regs to merge them with
	* the emulated registers and then copy the result to the dump.
	*/
	save_fp_regs(&current->thread.fp_regs);
	memcpy(fpregs, &current->thread.fp_regs, sizeof(s390_fp_regs));
	#else /* CONFIG_ARCH_S390X */
	save_fp_regs(fpregs);
	#endif /* CONFIG_ARCH_S390X */
	return 1;
	}

	/*
	* fill in the user structure for a core dump..
	*/
	void dump_thread(struct pt_regs * regs, struct user * dump)
	{

	/* changed the size calculations - should hopefully work better. lbt */
	dump->magic = CMAGIC;
	dump->start_code = 0;
	dump->start_stack = regs->gprs[15] & ~(PAGE_SIZE - 1);
	dump->u_tsize = current->mm->end_code >> PAGE_SHIFT;
	dump->u_dsize = (current->mm->brk + PAGE_SIZE - 1) >> PAGE_SHIFT;
	dump->u_dsize -= dump->u_tsize;
	dump->u_ssize = 0;
	if (dump->start_stack < TASK_SIZE)
	dump->u_ssize = (TASK_SIZE - dump->start_stack) >> PAGE_SHIFT;
	memcpy(&dump->regs, regs, sizeof(s390_regs));
	dump_fpu (regs, &dump->regs.fp_regs);
	dump->regs.per_info = current->thread.per_info;
	}

	unsigned long get_wchan(struct task_struct *p)
	{
	struct stack_frame sf, low, *high;
	unsigned long return_address;
	int count;

	if (!p \|\| p == current \|\| p->state == TASK_RUNNING \|\| !p->thread_info)
	return 0;
	low = (struct stack_frame *) p->thread_info;
	high = (struct stack_frame *)
	((unsigned long) p->thread_info + THREAD_SIZE) - 1;
	sf = (struct stack_frame *) (p->thread.ksp & PSW_ADDR_INSN);
	if (sf <= low \|\| sf > high)
	return 0;
	for (count = 0; count < 16; count++) {
	sf = (struct stack_frame *) (sf->back_chain & PSW_ADDR_INSN);
	if (sf <= low \|\| sf > high)
	return 0;
	return_address = sf->gprs[8] & PSW_ADDR_INSN;
	if (!in_sched_functions(return_address))
	return return_address;
	}
	return 0;
	}