Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 840 insertions, 0 deletions

diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
new file mode 100644
index 000000000000..fdfcf0488b49
--- /dev/null
+++ b/arch/s390/kernel/smp.c
@@ -0,0 +1,840 @@
+/*
+ *  arch/s390/kernel/smp.c
+ *
+ *  S390 version
+ *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *    Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
+ *               Martin Schwidefsky (schwidefsky@de.ibm.com)
+ *               Heiko Carstens (heiko.carstens@de.ibm.com)
+ *
+ *  based on other smp stuff by 
+ *    (c) 1995 Alan Cox, CymruNET Ltd  <alan@cymru.net>
+ *    (c) 1998 Ingo Molnar
+ *
+ * We work with logical cpu numbering everywhere we can. The only
+ * functions using the real cpu address (got from STAP) are the sigp
+ * functions. For all other functions we use the identity mapping.
+ * That means that cpu_number_map[i] == i for every cpu. cpu_number_map is
+ * used e.g. to find the idle task belonging to a logical cpu. Every array
+ * in the kernel is sorted by the logical cpu number and not by the physical
+ * one which is causing all the confusion with __cpu_logical_map and
+ * cpu_number_map in other architectures.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+
+#include <linux/mm.h>
+#include <linux/spinlock.h>
+#include <linux/kernel_stat.h>
+#include <linux/smp_lock.h>
+
+#include <linux/delay.h>
+#include <linux/cache.h>
+#include <linux/interrupt.h>
+#include <linux/cpu.h>
+
+#include <asm/sigp.h>
+#include <asm/pgalloc.h>
+#include <asm/irq.h>
+#include <asm/s390_ext.h>
+#include <asm/cpcmd.h>
+#include <asm/tlbflush.h>
+
+/* prototypes */
+
+extern volatile int __cpu_logical_map[];
+
+/*
+ * An array with a pointer the lowcore of every CPU.
+ */
+
+struct _lowcore *lowcore_ptr[NR_CPUS];
+
+cpumask_t cpu_online_map;
+cpumask_t cpu_possible_map;
+
+static struct task_struct *current_set[NR_CPUS];
+
+EXPORT_SYMBOL(cpu_online_map);
+
+/*
+ * Reboot, halt and power_off routines for SMP.
+ */
+extern char vmhalt_cmd[];
+extern char vmpoff_cmd[];
+
+extern void reipl(unsigned long devno);
+
+static void smp_ext_bitcall(int, ec_bit_sig);
+static void smp_ext_bitcall_others(ec_bit_sig);
+
+/*
+ * Structure and data for smp_call_function(). This is designed to minimise
+ * static memory requirements. It also looks cleaner.
+ */
+static DEFINE_SPINLOCK(call_lock);
+
+struct call_data_struct {
+	void (*func) (void *info);
+	void *info;
+	atomic_t started;
+	atomic_t finished;
+	int wait;
+};
+
+static struct call_data_struct * call_data;
+
+/*
+ * 'Call function' interrupt callback
+ */
+static void do_call_function(void)
+{
+	void (*func) (void *info) = call_data->func;
+	void *info = call_data->info;
+	int wait = call_data->wait;
+
+	atomic_inc(&call_data->started);
+	(*func)(info);
+	if (wait)
+		atomic_inc(&call_data->finished);
+}
+
+/*
+ * this function sends a 'generic call function' IPI to all other CPUs
+ * in the system.
+ */
+
+int smp_call_function (void (*func) (void *info), void *info, int nonatomic,
+			int wait)
+/*
+ * [SUMMARY] Run a function on all other CPUs.
+ * <func> The function to run. This must be fast and non-blocking.
+ * <info> An arbitrary pointer to pass to the function.
+ * <nonatomic> currently unused.
+ * <wait> If true, wait (atomically) until function has completed on other CPUs.
+ * [RETURNS] 0 on success, else a negative status code. Does not return until
+ * remote CPUs are nearly ready to execute <<func>> or are or have executed.
+ *
+ * You must not call this function with disabled interrupts or from a
+ * hardware interrupt handler or from a bottom half handler.
+ */
+{
+	struct call_data_struct data;
+	int cpus = num_online_cpus()-1;
+
+	if (cpus <= 0)
+		return 0;
+
+	/* Can deadlock when called with interrupts disabled */
+	WARN_ON(irqs_disabled());
+
+	data.func = func;
+	data.info = info;
+	atomic_set(&data.started, 0);
+	data.wait = wait;
+	if (wait)
+		atomic_set(&data.finished, 0);
+
+	spin_lock(&call_lock);
+	call_data = &data;
+	/* Send a message to all other CPUs and wait for them to respond */
+        smp_ext_bitcall_others(ec_call_function);
+
+	/* Wait for response */
+	while (atomic_read(&data.started) != cpus)
+		cpu_relax();
+
+	if (wait)
+		while (atomic_read(&data.finished) != cpus)
+			cpu_relax();
+	spin_unlock(&call_lock);
+
+	return 0;
+}
+
+/*
+ * Call a function on one CPU
+ * cpu : the CPU the function should be executed on
+ *
+ * You must not call this function with disabled interrupts or from a
+ * hardware interrupt handler. You may call it from a bottom half.
+ *
+ * It is guaranteed that the called function runs on the specified CPU,
+ * preemption is disabled.
+ */
+int smp_call_function_on(void (*func) (void *info), void *info,
+			 int nonatomic, int wait, int cpu)
+{
+	struct call_data_struct data;
+	int curr_cpu;
+
+	if (!cpu_online(cpu))
+		return -EINVAL;
+
+	/* disable preemption for local function call */
+	curr_cpu = get_cpu();
+
+	if (curr_cpu == cpu) {
+		/* direct call to function */
+		func(info);
+		put_cpu();
+		return 0;
+	}
+
+	data.func = func;
+	data.info = info;
+	atomic_set(&data.started, 0);
+	data.wait = wait;
+	if (wait)
+		atomic_set(&data.finished, 0);
+
+	spin_lock_bh(&call_lock);
+	call_data = &data;
+	smp_ext_bitcall(cpu, ec_call_function);
+
+	/* Wait for response */
+	while (atomic_read(&data.started) != 1)
+		cpu_relax();
+
+	if (wait)
+		while (atomic_read(&data.finished) != 1)
+			cpu_relax();
+
+	spin_unlock_bh(&call_lock);
+	put_cpu();
+	return 0;
+}
+EXPORT_SYMBOL(smp_call_function_on);
+
+static inline void do_send_stop(void)
+{
+        int cpu, rc;
+
+        /* stop all processors */
+	for_each_online_cpu(cpu) {
+		if (cpu == smp_processor_id())
+			continue;
+		do {
+			rc = signal_processor(cpu, sigp_stop);
+		} while (rc == sigp_busy);
+	}
+}
+
+static inline void do_store_status(void)
+{
+        int cpu, rc;
+
+        /* store status of all processors in their lowcores (real 0) */
+	for_each_online_cpu(cpu) {
+		if (cpu == smp_processor_id())
+			continue;
+		do {
+			rc = signal_processor_p(
+				(__u32)(unsigned long) lowcore_ptr[cpu], cpu,
+				sigp_store_status_at_address);
+		} while(rc == sigp_busy);
+        }
+}
+
+/*
+ * this function sends a 'stop' sigp to all other CPUs in the system.
+ * it goes straight through.
+ */
+void smp_send_stop(void)
+{
+        /* write magic number to zero page (absolute 0) */
+	lowcore_ptr[smp_processor_id()]->panic_magic = __PANIC_MAGIC;
+
+	/* stop other processors. */
+	do_send_stop();
+
+	/* store status of other processors. */
+	do_store_status();
+}
+
+/*
+ * Reboot, halt and power_off routines for SMP.
+ */
+
+static void do_machine_restart(void * __unused)
+{
+	int cpu;
+	static atomic_t cpuid = ATOMIC_INIT(-1);
+
+	if (atomic_compare_and_swap(-1, smp_processor_id(), &cpuid))
+		signal_processor(smp_processor_id(), sigp_stop);
+
+	/* Wait for all other cpus to enter stopped state */
+	for_each_online_cpu(cpu) {
+		if (cpu == smp_processor_id())
+			continue;
+		while(!smp_cpu_not_running(cpu))
+			cpu_relax();
+	}
+
+	/* Store status of other cpus. */
+	do_store_status();
+
+	/*
+	 * Finally call reipl. Because we waited for all other
+	 * cpus to enter this function we know that they do
+	 * not hold any s390irq-locks (the cpus have been
+	 * interrupted by an external interrupt and s390irq
+	 * locks are always held disabled).
+	 */
+	if (MACHINE_IS_VM)
+		cpcmd ("IPL", NULL, 0);
+	else
+		reipl (0x10000 | S390_lowcore.ipl_device);
+}
+
+void machine_restart_smp(char * __unused) 
+{
+        on_each_cpu(do_machine_restart, NULL, 0, 0);
+}
+
+static void do_wait_for_stop(void)
+{
+	unsigned long cr[16];
+
+	__ctl_store(cr, 0, 15);
+	cr[0] &= ~0xffff;
+	cr[6] = 0;
+	__ctl_load(cr, 0, 15);
+	for (;;)
+		enabled_wait();
+}
+
+static void do_machine_halt(void * __unused)
+{
+	static atomic_t cpuid = ATOMIC_INIT(-1);
+
+	if (atomic_compare_and_swap(-1, smp_processor_id(), &cpuid) == 0) {
+		smp_send_stop();
+		if (MACHINE_IS_VM && strlen(vmhalt_cmd) > 0)
+			cpcmd(vmhalt_cmd, NULL, 0);
+		signal_processor(smp_processor_id(),
+				 sigp_stop_and_store_status);
+	}
+	do_wait_for_stop();
+}
+
+void machine_halt_smp(void)
+{
+        on_each_cpu(do_machine_halt, NULL, 0, 0);
+}
+
+static void do_machine_power_off(void * __unused)
+{
+	static atomic_t cpuid = ATOMIC_INIT(-1);
+
+	if (atomic_compare_and_swap(-1, smp_processor_id(), &cpuid) == 0) {
+		smp_send_stop();
+		if (MACHINE_IS_VM && strlen(vmpoff_cmd) > 0)
+			cpcmd(vmpoff_cmd, NULL, 0);
+		signal_processor(smp_processor_id(),
+				 sigp_stop_and_store_status);
+	}
+	do_wait_for_stop();
+}
+
+void machine_power_off_smp(void)
+{
+        on_each_cpu(do_machine_power_off, NULL, 0, 0);
+}
+
+/*
+ * This is the main routine where commands issued by other
+ * cpus are handled.
+ */
+
+void do_ext_call_interrupt(struct pt_regs *regs, __u16 code)
+{
+        unsigned long bits;
+
+        /*
+         * handle bit signal external calls
+         *
+         * For the ec_schedule signal we have to do nothing. All the work
+         * is done automatically when we return from the interrupt.
+         */
+	bits = xchg(&S390_lowcore.ext_call_fast, 0);
+
+	if (test_bit(ec_call_function, &bits)) 
+		do_call_function();
+}
+
+/*
+ * Send an external call sigp to another cpu and return without waiting
+ * for its completion.
+ */
+static void smp_ext_bitcall(int cpu, ec_bit_sig sig)
+{
+        /*
+         * Set signaling bit in lowcore of target cpu and kick it
+         */
+	set_bit(sig, (unsigned long *) &lowcore_ptr[cpu]->ext_call_fast);
+	while(signal_processor(cpu, sigp_external_call) == sigp_busy)
+		udelay(10);
+}
+
+/*
+ * Send an external call sigp to every other cpu in the system and
+ * return without waiting for its completion.
+ */
+static void smp_ext_bitcall_others(ec_bit_sig sig)
+{
+        int cpu;
+
+	for_each_online_cpu(cpu) {
+		if (cpu == smp_processor_id())
+                        continue;
+                /*
+                 * Set signaling bit in lowcore of target cpu and kick it
+                 */
+		set_bit(sig, (unsigned long *) &lowcore_ptr[cpu]->ext_call_fast);
+		while (signal_processor(cpu, sigp_external_call) == sigp_busy)
+			udelay(10);
+        }
+}
+
+#ifndef CONFIG_ARCH_S390X
+/*
+ * this function sends a 'purge tlb' signal to another CPU.
+ */
+void smp_ptlb_callback(void *info)
+{
+	local_flush_tlb();
+}
+
+void smp_ptlb_all(void)
+{
+        on_each_cpu(smp_ptlb_callback, NULL, 0, 1);
+}
+EXPORT_SYMBOL(smp_ptlb_all);
+#endif /* ! CONFIG_ARCH_S390X */
+
+/*
+ * this function sends a 'reschedule' IPI to another CPU.
+ * it goes straight through and wastes no time serializing
+ * anything. Worst case is that we lose a reschedule ...
+ */
+void smp_send_reschedule(int cpu)
+{
+        smp_ext_bitcall(cpu, ec_schedule);
+}
+
+/*
+ * parameter area for the set/clear control bit callbacks
+ */
+typedef struct
+{
+	__u16 start_ctl;
+	__u16 end_ctl;
+	unsigned long orvals[16];
+	unsigned long andvals[16];
+} ec_creg_mask_parms;
+
+/*
+ * callback for setting/clearing control bits
+ */
+void smp_ctl_bit_callback(void *info) {
+	ec_creg_mask_parms *pp;
+	unsigned long cregs[16];
+	int i;
+	
+	pp = (ec_creg_mask_parms *) info;
+	__ctl_store(cregs[pp->start_ctl], pp->start_ctl, pp->end_ctl);
+	for (i = pp->start_ctl; i <= pp->end_ctl; i++)
+		cregs[i] = (cregs[i] & pp->andvals[i]) | pp->orvals[i];
+	__ctl_load(cregs[pp->start_ctl], pp->start_ctl, pp->end_ctl);
+}
+
+/*
+ * Set a bit in a control register of all cpus
+ */
+void smp_ctl_set_bit(int cr, int bit) {
+        ec_creg_mask_parms parms;
+
+	parms.start_ctl = cr;
+	parms.end_ctl = cr;
+	parms.orvals[cr] = 1 << bit;
+	parms.andvals[cr] = -1L;
+	preempt_disable();
+	smp_call_function(smp_ctl_bit_callback, &parms, 0, 1);
+        __ctl_set_bit(cr, bit);
+	preempt_enable();
+}
+
+/*
+ * Clear a bit in a control register of all cpus
+ */
+void smp_ctl_clear_bit(int cr, int bit) {
+        ec_creg_mask_parms parms;
+
+	parms.start_ctl = cr;
+	parms.end_ctl = cr;
+	parms.orvals[cr] = 0;
+	parms.andvals[cr] = ~(1L << bit);
+	preempt_disable();
+	smp_call_function(smp_ctl_bit_callback, &parms, 0, 1);
+        __ctl_clear_bit(cr, bit);
+	preempt_enable();
+}
+
+/*
+ * Lets check how many CPUs we have.
+ */
+
+void
+__init smp_check_cpus(unsigned int max_cpus)
+{
+	int cpu, num_cpus;
+	__u16 boot_cpu_addr;
+
+	/*
+	 * cpu 0 is the boot cpu. See smp_prepare_boot_cpu.
+	 */
+
+	boot_cpu_addr = S390_lowcore.cpu_data.cpu_addr;
+	current_thread_info()->cpu = 0;
+	num_cpus = 1;
+	for (cpu = 0; cpu <= 65535 && num_cpus < max_cpus; cpu++) {
+		if ((__u16) cpu == boot_cpu_addr)
+			continue;
+		__cpu_logical_map[num_cpus] = (__u16) cpu;
+		if (signal_processor(num_cpus, sigp_sense) ==
+		    sigp_not_operational)
+			continue;
+		cpu_set(num_cpus, cpu_present_map);
+		num_cpus++;
+	}
+
+	for (cpu = 1; cpu < max_cpus; cpu++)
+		cpu_set(cpu, cpu_possible_map);
+
+	printk("Detected %d CPU's\n",(int) num_cpus);
+	printk("Boot cpu address %2X\n", boot_cpu_addr);
+}
+
+/*
+ *      Activate a secondary processor.
+ */
+extern void init_cpu_timer(void);
+extern void init_cpu_vtimer(void);
+extern int pfault_init(void);
+extern void pfault_fini(void);
+
+int __devinit start_secondary(void *cpuvoid)
+{
+        /* Setup the cpu */
+        cpu_init();
+        /* init per CPU timer */
+        init_cpu_timer();
+#ifdef CONFIG_VIRT_TIMER
+        init_cpu_vtimer();
+#endif
+#ifdef CONFIG_PFAULT
+	/* Enable pfault pseudo page faults on this cpu. */
+	pfault_init();
+#endif
+	/* Mark this cpu as online */
+	cpu_set(smp_processor_id(), cpu_online_map);
+	/* Switch on interrupts */
+	local_irq_enable();
+        /* Print info about this processor */
+        print_cpu_info(&S390_lowcore.cpu_data);
+        /* cpu_idle will call schedule for us */
+        cpu_idle();
+        return 0;
+}
+
+static void __init smp_create_idle(unsigned int cpu)
+{
+	struct task_struct *p;
+
+	/*
+	 *  don't care about the psw and regs settings since we'll never
+	 *  reschedule the forked task.
+	 */
+	p = fork_idle(cpu);
+	if (IS_ERR(p))
+		panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p));
+	current_set[cpu] = p;
+}
+
+/* Reserving and releasing of CPUs */
+
+static DEFINE_SPINLOCK(smp_reserve_lock);
+static int smp_cpu_reserved[NR_CPUS];
+
+int
+smp_get_cpu(cpumask_t cpu_mask)
+{
+	unsigned long flags;
+	int cpu;
+
+	spin_lock_irqsave(&smp_reserve_lock, flags);
+	/* Try to find an already reserved cpu. */
+	for_each_cpu_mask(cpu, cpu_mask) {
+		if (smp_cpu_reserved[cpu] != 0) {
+			smp_cpu_reserved[cpu]++;
+			/* Found one. */
+			goto out;
+		}
+	}
+	/* Reserve a new cpu from cpu_mask. */
+	for_each_cpu_mask(cpu, cpu_mask) {
+		if (cpu_online(cpu)) {
+			smp_cpu_reserved[cpu]++;
+			goto out;
+		}
+	}
+	cpu = -ENODEV;
+out:
+	spin_unlock_irqrestore(&smp_reserve_lock, flags);
+	return cpu;
+}
+
+void
+smp_put_cpu(int cpu)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&smp_reserve_lock, flags);
+	smp_cpu_reserved[cpu]--;
+	spin_unlock_irqrestore(&smp_reserve_lock, flags);
+}
+
+static inline int
+cpu_stopped(int cpu)
+{
+	__u32 status;
+
+	/* Check for stopped state */
+	if (signal_processor_ps(&status, 0, cpu, sigp_sense) == sigp_status_stored) {
+		if (status & 0x40)
+			return 1;
+	}
+	return 0;
+}
+
+/* Upping and downing of CPUs */
+
+int
+__cpu_up(unsigned int cpu)
+{
+	struct task_struct *idle;
+        struct _lowcore    *cpu_lowcore;
+	struct stack_frame *sf;
+        sigp_ccode          ccode;
+	int                 curr_cpu;
+
+	for (curr_cpu = 0; curr_cpu <= 65535; curr_cpu++) {
+		__cpu_logical_map[cpu] = (__u16) curr_cpu;
+		if (cpu_stopped(cpu))
+			break;
+	}
+
+	if (!cpu_stopped(cpu))
+		return -ENODEV;
+
+	ccode = signal_processor_p((__u32)(unsigned long)(lowcore_ptr[cpu]),
+				   cpu, sigp_set_prefix);
+	if (ccode){
+		printk("sigp_set_prefix failed for cpu %d "
+		       "with condition code %d\n",
+		       (int) cpu, (int) ccode);
+		return -EIO;
+	}
+
+	idle = current_set[cpu];
+        cpu_lowcore = lowcore_ptr[cpu];
+	cpu_lowcore->kernel_stack = (unsigned long)
+		idle->thread_info + (THREAD_SIZE);
+	sf = (struct stack_frame *) (cpu_lowcore->kernel_stack
+				     - sizeof(struct pt_regs)
+				     - sizeof(struct stack_frame));
+	memset(sf, 0, sizeof(struct stack_frame));
+	sf->gprs[9] = (unsigned long) sf;
+	cpu_lowcore->save_area[15] = (unsigned long) sf;
+	__ctl_store(cpu_lowcore->cregs_save_area[0], 0, 15);
+	__asm__ __volatile__("stam  0,15,0(%0)"
+			     : : "a" (&cpu_lowcore->access_regs_save_area)
+			     : "memory");
+	cpu_lowcore->percpu_offset = __per_cpu_offset[cpu];
+        cpu_lowcore->current_task = (unsigned long) idle;
+        cpu_lowcore->cpu_data.cpu_nr = cpu;
+	eieio();
+	signal_processor(cpu,sigp_restart);
+
+	while (!cpu_online(cpu))
+		cpu_relax();
+	return 0;
+}
+
+int
+__cpu_disable(void)
+{
+	unsigned long flags;
+	ec_creg_mask_parms cr_parms;
+
+	spin_lock_irqsave(&smp_reserve_lock, flags);
+	if (smp_cpu_reserved[smp_processor_id()] != 0) {
+		spin_unlock_irqrestore(&smp_reserve_lock, flags);
+		return -EBUSY;
+	}
+
+#ifdef CONFIG_PFAULT
+	/* Disable pfault pseudo page faults on this cpu. */
+	pfault_fini();
+#endif
+
+	/* disable all external interrupts */
+
+	cr_parms.start_ctl = 0;
+	cr_parms.end_ctl = 0;
+	cr_parms.orvals[0] = 0;
+	cr_parms.andvals[0] = ~(1<<15 | 1<<14 | 1<<13 | 1<<12 |
+				1<<11 | 1<<10 | 1<< 6 | 1<< 4);
+	smp_ctl_bit_callback(&cr_parms);
+
+	/* disable all I/O interrupts */
+
+	cr_parms.start_ctl = 6;
+	cr_parms.end_ctl = 6;
+	cr_parms.orvals[6] = 0;
+	cr_parms.andvals[6] = ~(1<<31 | 1<<30 | 1<<29 | 1<<28 |
+				1<<27 | 1<<26 | 1<<25 | 1<<24);
+	smp_ctl_bit_callback(&cr_parms);
+
+	/* disable most machine checks */
+
+	cr_parms.start_ctl = 14;
+	cr_parms.end_ctl = 14;
+	cr_parms.orvals[14] = 0;
+	cr_parms.andvals[14] = ~(1<<28 | 1<<27 | 1<<26 | 1<<25 | 1<<24);
+	smp_ctl_bit_callback(&cr_parms);
+
+	spin_unlock_irqrestore(&smp_reserve_lock, flags);
+	return 0;
+}
+
+void
+__cpu_die(unsigned int cpu)
+{
+	/* Wait until target cpu is down */
+	while (!smp_cpu_not_running(cpu))
+		cpu_relax();
+	printk("Processor %d spun down\n", cpu);
+}
+
+void
+cpu_die(void)
+{
+	idle_task_exit();
+	signal_processor(smp_processor_id(), sigp_stop);
+	BUG();
+	for(;;);
+}
+
+/*
+ *	Cycle through the processors and setup structures.
+ */
+
+void __init smp_prepare_cpus(unsigned int max_cpus)
+{
+	unsigned long stack;
+	unsigned int cpu;
+        int i;
+
+        /* request the 0x1202 external interrupt */
+        if (register_external_interrupt(0x1202, do_ext_call_interrupt) != 0)
+                panic("Couldn't request external interrupt 0x1202");
+        smp_check_cpus(max_cpus);
+        memset(lowcore_ptr,0,sizeof(lowcore_ptr));  
+        /*
+         *  Initialize prefix pages and stacks for all possible cpus
+         */
+	print_cpu_info(&S390_lowcore.cpu_data);
+
+        for(i = 0; i < NR_CPUS; i++) {
+		if (!cpu_possible(i))
+			continue;
+		lowcore_ptr[i] = (struct _lowcore *)
+			__get_free_pages(GFP_KERNEL|GFP_DMA, 
+					sizeof(void*) == 8 ? 1 : 0);
+		stack = __get_free_pages(GFP_KERNEL,ASYNC_ORDER);
+		if (lowcore_ptr[i] == NULL || stack == 0ULL)
+			panic("smp_boot_cpus failed to allocate memory\n");
+
+		*(lowcore_ptr[i]) = S390_lowcore;
+		lowcore_ptr[i]->async_stack = stack + (ASYNC_SIZE);
+#ifdef CONFIG_CHECK_STACK
+		stack = __get_free_pages(GFP_KERNEL,0);
+		if (stack == 0ULL)
+			panic("smp_boot_cpus failed to allocate memory\n");
+		lowcore_ptr[i]->panic_stack = stack + (PAGE_SIZE);
+#endif
+	}
+	set_prefix((u32)(unsigned long) lowcore_ptr[smp_processor_id()]);
+
+	for_each_cpu(cpu)
+		if (cpu != smp_processor_id())
+			smp_create_idle(cpu);
+}
+
+void __devinit smp_prepare_boot_cpu(void)
+{
+	BUG_ON(smp_processor_id() != 0);
+
+	cpu_set(0, cpu_online_map);
+	cpu_set(0, cpu_present_map);
+	cpu_set(0, cpu_possible_map);
+	S390_lowcore.percpu_offset = __per_cpu_offset[0];
+	current_set[0] = current;
+}
+
+void smp_cpus_done(unsigned int max_cpus)
+{
+	cpu_present_map = cpu_possible_map;
+}
+
+/*
+ * the frequency of the profiling timer can be changed
+ * by writing a multiplier value into /proc/profile.
+ *
+ * usually you want to run this on all CPUs ;)
+ */
+int setup_profiling_timer(unsigned int multiplier)
+{
+        return 0;
+}
+
+static DEFINE_PER_CPU(struct cpu, cpu_devices);
+
+static int __init topology_init(void)
+{
+	int cpu;
+	int ret;
+
+	for_each_cpu(cpu) {
+		ret = register_cpu(&per_cpu(cpu_devices, cpu), cpu, NULL);
+		if (ret)
+			printk(KERN_WARNING "topology_init: register_cpu %d "
+			       "failed (%d)\n", cpu, ret);
+	}
+	return 0;
+}
+
+subsys_initcall(topology_init);
+
+EXPORT_SYMBOL(cpu_possible_map);
+EXPORT_SYMBOL(lowcore_ptr);
+EXPORT_SYMBOL(smp_ctl_set_bit);
+EXPORT_SYMBOL(smp_ctl_clear_bit);
+EXPORT_SYMBOL(smp_call_function);
+EXPORT_SYMBOL(smp_get_cpu);
+EXPORT_SYMBOL(smp_put_cpu);
+