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authorTianyu Lan <Tianyu.Lan@microsoft.com>2018-07-19 08:40:06 +0000
committerPaolo Bonzini <pbonzini@redhat.com>2018-08-06 17:59:04 +0200
commiteb914cfe72f4c948b2318b1381f6d2e08d43b63c (patch)
tree7fcb5c02989a8db5ddaf9c1a8ca7a4e9619408f0 /arch/x86/hyperv
parent3553ae5690a84a5baae5baa329467b3df2d99f72 (diff)
X86/Hyper-V: Add flush HvFlushGuestPhysicalAddressSpace hypercall support
Hyper-V supports a pv hypercall HvFlushGuestPhysicalAddressSpace to flush nested VM address space mapping in l1 hypervisor and it's to reduce overhead of flushing ept tlb among vcpus. This patch is to implement it. Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com> Acked-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/hyperv')
-rw-r--r--arch/x86/hyperv/Makefile2
-rw-r--r--arch/x86/hyperv/nested.c53
2 files changed, 54 insertions, 1 deletions
diff --git a/arch/x86/hyperv/Makefile b/arch/x86/hyperv/Makefile
index b173d404e3df..b21ee65c4101 100644
--- a/arch/x86/hyperv/Makefile
+++ b/arch/x86/hyperv/Makefile
@@ -1,2 +1,2 @@
-obj-y := hv_init.o mmu.o
+obj-y := hv_init.o mmu.o nested.o
obj-$(CONFIG_X86_64) += hv_apic.o
diff --git a/arch/x86/hyperv/nested.c b/arch/x86/hyperv/nested.c
new file mode 100644
index 000000000000..08f914217518
--- /dev/null
+++ b/arch/x86/hyperv/nested.c
@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Hyper-V nested virtualization code.
+ *
+ * Copyright (C) 2018, Microsoft, Inc.
+ *
+ * Author : Lan Tianyu <Tianyu.Lan@microsoft.com>
+ */
+
+
+#include <linux/types.h>
+#include <asm/hyperv-tlfs.h>
+#include <asm/mshyperv.h>
+#include <asm/tlbflush.h>
+
+int hyperv_flush_guest_mapping(u64 as)
+{
+ struct hv_guest_mapping_flush **flush_pcpu;
+ struct hv_guest_mapping_flush *flush;
+ u64 status;
+ unsigned long flags;
+ int ret = -ENOTSUPP;
+
+ if (!hv_hypercall_pg)
+ goto fault;
+
+ local_irq_save(flags);
+
+ flush_pcpu = (struct hv_guest_mapping_flush **)
+ this_cpu_ptr(hyperv_pcpu_input_arg);
+
+ flush = *flush_pcpu;
+
+ if (unlikely(!flush)) {
+ local_irq_restore(flags);
+ goto fault;
+ }
+
+ flush->address_space = as;
+ flush->flags = 0;
+
+ status = hv_do_hypercall(HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_SPACE,
+ flush, NULL);
+ local_irq_restore(flags);
+
+ if (!(status & HV_HYPERCALL_RESULT_MASK))
+ ret = 0;
+
+fault:
+ return ret;
+}
+EXPORT_SYMBOL_GPL(hyperv_flush_guest_mapping);