[Qemu-devel] [PATCH v3] kvm: add set_one_reg/get_one_reg helpers

[Alexey Kardashevskiy <aik@ozlabs.ru>]

This adds QEMU wrappers for KVM_SET_ONE_REG/KVM_GET_ONE_REG ioctls.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
---
Changes:
v3:
* changed comments

v2:
* added Doc Comments
* removed error_print
---
 include/sysemu/kvm.h | 21 +++++++++++++++++++++
 kvm-all.c            | 18 ++++++++++++++++++
 2 files changed, 39 insertions(+)

diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h
index c7bc07b..9080ffe 100644
--- a/include/sysemu/kvm.h
+++ b/include/sysemu/kvm.h
@@ -319,4 +319,25 @@ int kvm_irqchip_remove_irqfd_notifier(KVMState *s, EventNotifier *n, int virq);
 void kvm_pc_gsi_handler(void *opaque, int n, int level);
 void kvm_pc_setup_irq_routing(bool pci_enabled);
 void kvm_init_irq_routing(KVMState *s);
+
+/**
+ * kvm_set_one_reg - set a register value in KVM via KVM_SET_ONE_REG ioctl
+ * @id: The register ID
+ * @addr: The pointer to a value must point to a variable of the correct
+ * type/size for the register being accessed.
+ *
+ * Returns: 0 on success, or a negative errno on failure.
+ */
+int kvm_set_one_reg(CPUState *cs, uint64_t id, void *addr);
+
+/**
+ * kvm_get_one_reg - get a register value from KVM via KVM_GET_ONE_REG ioctl
+ * @id: The register ID
+ * @addr: The pointer to a value must point to a variable of the correct
+ * type/size for the register being accessed.
+ *
+ * Returns: 0 on success, or a negative errno on failure.
+ */
+int kvm_get_one_reg(CPUState *cs, uint64_t id, void *addr);
+
 #endif
diff --git a/kvm-all.c b/kvm-all.c
index ded7fc8..cdc32ec 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -2049,3 +2049,21 @@ int kvm_on_sigbus(int code, void *addr)
 {
     return kvm_arch_on_sigbus(code, addr);
 }
+
+int kvm_set_one_reg(CPUState *cs, uint64_t id, void *addr)
+{
+    struct kvm_one_reg reg = {
+        .id = id,
+        .addr = (uintptr_t)addr,
+    };
+    return kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
+}
+
+int kvm_get_one_reg(CPUState *cs, uint64_t id, void *addr)
+{
+    struct kvm_one_reg reg = {
+        .id = id,
+        .addr = (uintptr_t)addr,
+    };
+    return kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
+}
-- 
1.8.4.rc4