.gitignore: ignore emacs backup and temporary files.

[linux-2.6] / arch / s390 / kernel / smp.c

diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 85060659fb123d491227d849963dad292e13eeab..818bd09c0260e05fb3a58eb2764f88e8f055a585 100644 (file)
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -626,13 +626,17 @@ static int __cpuinit smp_alloc_lowcore(int cpu)
        if (!lowcore)
                return -ENOMEM;
        async_stack = __get_free_pages(GFP_KERNEL, ASYNC_ORDER);
-       if (!async_stack)
-               goto out_async_stack;
        panic_stack = __get_free_page(GFP_KERNEL);
-       if (!panic_stack)
-               goto out_panic_stack;
-
-       *lowcore = S390_lowcore;
+       if (!panic_stack || !async_stack)
+               goto out;
+       /*
+        * Only need to copy the first 512 bytes from address 0. But since
+        * the compiler emits a warning if src == NULL for memcpy use copy_page
+        * instead. Copies more than needed but this code is not performance
+        * critical.
+        */
+       copy_page(lowcore, &S390_lowcore);
+       memset((void *)lowcore + 512, 0, sizeof(*lowcore) - 512);
        lowcore->async_stack = async_stack + ASYNC_SIZE;
        lowcore->panic_stack = panic_stack + PAGE_SIZE;
 
@@ -653,9 +657,8 @@ static int __cpuinit smp_alloc_lowcore(int cpu)
 out_save_area:
        free_page(panic_stack);
 #endif
-out_panic_stack:
+out:
        free_pages(async_stack, ASYNC_ORDER);
-out_async_stack:
        free_pages((unsigned long) lowcore, lc_order);
        return -ENOMEM;
 }
@@ -719,8 +722,8 @@ int __cpuinit __cpu_up(unsigned int cpu)
        cpu_lowcore->percpu_offset = __per_cpu_offset[cpu];
        cpu_lowcore->current_task = (unsigned long) idle;
        cpu_lowcore->cpu_data.cpu_nr = cpu;
-       cpu_lowcore->softirq_pending = 0;
-       cpu_lowcore->ext_call_fast = 0;
+       cpu_lowcore->kernel_asce = S390_lowcore.kernel_asce;
+       cpu_lowcore->ipl_device = S390_lowcore.ipl_device;
        eieio();
 
        while (signal_processor(cpu, sigp_restart) == sigp_busy)
@@ -797,23 +800,43 @@ void cpu_die(void)
 
 void __init smp_prepare_cpus(unsigned int max_cpus)
 {
+#ifndef CONFIG_64BIT
+       unsigned long save_area = 0;
+#endif
+       unsigned long async_stack, panic_stack;
+       struct _lowcore *lowcore;
        unsigned int cpu;
+       int lc_order;
 
        smp_detect_cpus();
 
        /* request the 0x1201 emergency signal external interrupt */
        if (register_external_interrupt(0x1201, do_ext_call_interrupt) != 0)
                panic("Couldn't request external interrupt 0x1201");
-       memset(lowcore_ptr, 0, sizeof(lowcore_ptr));
        print_cpu_info(&S390_lowcore.cpu_data);
-       smp_alloc_lowcore(smp_processor_id());
 
+       /* Reallocate current lowcore, but keep its contents. */
+       lc_order = sizeof(long) == 8 ? 1 : 0;
+       lowcore = (void *) __get_free_pages(GFP_KERNEL | GFP_DMA, lc_order);
+       panic_stack = __get_free_page(GFP_KERNEL);
+       async_stack = __get_free_pages(GFP_KERNEL, ASYNC_ORDER);
 #ifndef CONFIG_64BIT
        if (MACHINE_HAS_IEEE)
-               ctl_set_bit(14, 29); /* enable extended save area */
+               save_area = get_zeroed_page(GFP_KERNEL);
 #endif
-       set_prefix((u32)(unsigned long) lowcore_ptr[smp_processor_id()]);
-
+       local_irq_disable();
+       local_mcck_disable();
+       lowcore_ptr[smp_processor_id()] = lowcore;
+       *lowcore = S390_lowcore;
+       lowcore->panic_stack = panic_stack + PAGE_SIZE;
+       lowcore->async_stack = async_stack + ASYNC_SIZE;
+#ifndef CONFIG_64BIT
+       if (MACHINE_HAS_IEEE)
+               lowcore->extended_save_area_addr = (u32) save_area;
+#endif
+       set_prefix((u32)(unsigned long) lowcore);
+       local_mcck_enable();
+       local_irq_enable();
        for_each_possible_cpu(cpu)
                if (cpu != smp_processor_id())
                        smp_create_idle(cpu);