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Diffstat (limited to 'arch/x86/hyperv/hv_init.c')
-rw-r--r--arch/x86/hyperv/hv_init.c62
1 files changed, 62 insertions, 0 deletions
diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
new file mode 100644
index 000000000000..3206bfda586d
--- /dev/null
+++ b/arch/x86/hyperv/hv_init.c
@@ -0,0 +1,62 @@
+/*
+ * X86 specific Hyper-V initialization code.
+ *
+ * Copyright (C) 2016, Microsoft, Inc.
+ *
+ * Author : K. Y. Srinivasan <kys@microsoft.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for more
+ * details.
+ *
+ */
+
+#include <linux/types.h>
+#include <asm/hypervisor.h>
+#include <asm/hyperv.h>
+#include <asm/mshyperv.h>
+#include <linux/version.h>
+#include <linux/vmalloc.h>
+#include <linux/mm.h>
+
+void *hv_hypercall_pg;
+/*
+ * This function is to be invoked early in the boot sequence after the
+ * hypervisor has been detected.
+ *
+ * 1. Setup the hypercall page.
+ */
+void hyperv_init(void)
+{
+ u64 guest_id;
+ union hv_x64_msr_hypercall_contents hypercall_msr;
+
+ if (x86_hyper != &x86_hyper_ms_hyperv)
+ return;
+
+ /*
+ * Setup the hypercall page and enable hypercalls.
+ * 1. Register the guest ID
+ * 2. Enable the hypercall and register the hypercall page
+ */
+ guest_id = generate_guest_id(0, LINUX_VERSION_CODE, 0);
+ wrmsrl(HV_X64_MSR_GUEST_OS_ID, guest_id);
+
+ hv_hypercall_pg = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_EXEC);
+ if (hv_hypercall_pg == NULL) {
+ wrmsrl(HV_X64_MSR_GUEST_OS_ID, 0);
+ return;
+ }
+
+ rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+ hypercall_msr.enable = 1;
+ hypercall_msr.guest_physical_address = vmalloc_to_pfn(hv_hypercall_pg);
+ wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+}
+EXPORT_SYMBOL_GPL(hv_hypercall_pg);