[v2,7/8] x86/hyperv: retrieve vp_index from Hyper-V

Commit Message

Wei Liu Jan. 3, 2020, 4:08 p.m. UTC

This will be useful when invoking hypercall that targets specific
vcpu(s).

Signed-off-by: Wei Liu <[e-mail]>
---
v2:
1. Fold into setup_pcpu_arg function
---
 xen/arch/x86/guest/hyperv/hyperv.c | 5 +++++
 xen/include/asm-x86/guest/hyperv.h | 1 +
 2 files changed, 6 insertions(+)

Patch

diff --git a/xen/arch/x86/guest/hyperv/hyperv.c b/xen/arch/x86/guest/hyperv/hyperv.c
index 03027bd453..5c5aed46cb 100644
--- a/xen/arch/x86/guest/hyperv/hyperv.c
+++ b/xen/arch/x86/guest/hyperv/hyperv.c
@@ -28,6 +28,7 @@  struct ms_hyperv_info __read_mostly ms_hyperv;
 
 extern char hv_hypercall_page[];
 DEFINE_PER_CPU_READ_MOSTLY(struct hyperv_pcpu_page, hv_pcpu_input_arg);
+DEFINE_PER_CPU_READ_MOSTLY(unsigned int, hv_vp_index);
 
 static const struct hypervisor_ops ops;
 const struct hypervisor_ops *__init hyperv_probe(void)
@@ -89,6 +90,7 @@  static void setup_hypercall_pcpu_arg(void)
     struct page_info *pg;
     void *mapping;
     unsigned int cpu = smp_processor_id();
+    uint64_t vp_index_msr;
 
     pg = alloc_domheap_page(NULL, 0);
     if ( !pg )
@@ -100,6 +102,9 @@  static void setup_hypercall_pcpu_arg(void)
 
     this_cpu(hv_pcpu_input_arg).maddr = page_to_maddr(pg);
     this_cpu(hv_pcpu_input_arg).mapping = mapping;
+
+    rdmsrl(HV_X64_MSR_VP_INDEX, vp_index_msr);
+    this_cpu(hv_vp_index) = vp_index_msr;
 }
 
 static void __init setup(void)
diff --git a/xen/include/asm-x86/guest/hyperv.h b/xen/include/asm-x86/guest/hyperv.h
index 83f297468f..4b635829f3 100644
--- a/xen/include/asm-x86/guest/hyperv.h
+++ b/xen/include/asm-x86/guest/hyperv.h
@@ -70,6 +70,7 @@  struct hyperv_pcpu_page {
     void *mapping;
 };
 DECLARE_PER_CPU(struct hyperv_pcpu_page, hv_pcpu_input_arg);
+DECLARE_PER_CPU(unsigned int, hv_vp_index);
 
 const struct hypervisor_ops *hyperv_probe(void);