[XEN] Kexec / Kdump: Code shared between x86_32 and x86_64

This patch contains Kexec / Kdump code shared between x86_32 and x86_64.

Signed-Off-By: Magnus Damm <magnus@valinux.co.jp>
Signed-Off-By: Simon Horman <horms@verge.net.au>

1 files changed, 112 insertions, 3 deletions

diff --git a/xen/arch/x86/crash.c b/xen/arch/x86/crash.c
index f1729786ea..73ed160021 100644
--- a/xen/arch/x86/crash.c
+++ b/xen/arch/x86/crash.c
@@ -1,10 +1,119 @@
-#include <xen/lib.h>       /* for printk() used in stub */
+/******************************************************************************
+ * crash.c
+ * 
+ * Based heavily on arch/i386/kernel/crash.c from Linux 2.6.16
+ *
+ * Xen port written by:
+ * - Simon 'Horms' Horman <horms@verge.net.au>
+ * - Magnus Damm <magnus@valinux.co.jp>
+ */
+
+#include <asm/atomic.h>
+#include <asm/elf.h>
+#include <asm/percpu.h>
+#include <asm/kexec.h>
 #include <xen/types.h>
-#include <public/kexec.h>
+#include <xen/irq.h>
+#include <asm/ipi.h>
+#include <asm/nmi.h>
+#include <xen/string.h>
+#include <xen/elf.h>
+#include <xen/elfcore.h>
+#include <xen/smp.h>
+#include <xen/delay.h>
+#include <xen/perfc.h>
+#include <xen/kexec.h>
+#include <xen/sched.h>
+#include <public/xen.h>
+#include <asm/hvm/hvm.h>
+
+#ifdef CONFIG_SMP
+static atomic_t waiting_for_crash_ipi;
+
+static int crash_nmi_callback(struct cpu_user_regs *regs, int cpu)
+{
+	/* Don't do anything if this handler is invoked on crashing cpu.
+	 * Otherwise, system will completely hang. Crashing cpu can get
+	 * an NMI if system was initially booted with nmi_watchdog parameter.
+	 */
+	if (cpu == crashing_cpu)
+		return 1;
+	local_irq_disable();
+
+    machine_crash_save_cpu();
+	disable_local_APIC();
+	atomic_dec(&waiting_for_crash_ipi);
+	hvm_disable();
+
+    for ( ; ; )
+        __asm__ __volatile__ ( "hlt" );
+
+	return 1;
+}
+
+/*
+ * By using the NMI code instead of a vector we just sneak thru the
+ * word generator coming out with just what we want.  AND it does
+ * not matter if clustered_apic_mode is set or not.
+ */
+static void smp_send_nmi_allbutself(void)
+{
+    cpumask_t allbutself = cpu_online_map;
+
+   	cpu_clear(smp_processor_id(), allbutself);
+    send_IPI_mask(allbutself, APIC_DM_NMI);
+}
+
+static void nmi_shootdown_cpus(void)
+{
+	unsigned long msecs;
+
+	atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
+	/* Would it be better to replace the trap vector here? */
+	set_nmi_callback(crash_nmi_callback);
+	/* Ensure the new callback function is set before sending
+	 * out the NMI
+	 */
+	wmb();
+
+	smp_send_nmi_allbutself();
+
+	msecs = 1000; /* Wait at most a second for the other cpus to stop */
+	while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
+		mdelay(1);
+		msecs--;
+	}
+
+	/* Leave the nmi callback set */
+    disable_local_APIC();
+}
+#endif
+
+static void crash_save_xen_notes(void)
+{
+    crash_xen_info_t *info;
+
+    info = machine_crash_save_info();
+
+    info->dom0_pfn_to_mfn_frame_list_list = \
+        dom0->shared_info->arch.pfn_to_mfn_frame_list_list;
+}
 
 void machine_crash_shutdown(void)
 {
-    printk("STUB: " __FILE__ ": %s: not implemented\n", __FUNCTION__);
+	printk("machine_crash_shutdown: %d\n", smp_processor_id());
+	local_irq_disable();
+
+#ifdef CONFIG_SMP
+	nmi_shootdown_cpus();
+#endif
+
+#ifdef CONFIG_X86_IO_APIC
+    disable_IO_APIC();
+#endif
+    hvm_disable();
+
+    crash_save_xen_notes();
 }
 
 /*