[Qemu-devel] [PATCH 13/17] target-ppc: Add helper for KVM_PPC_RTAS_DEFINE_TOKEN

[Alexey Kardashevskiy <aik@ozlabs.ru>]

From: David Gibson <david@gibson.dropbear.id.au>

Recent PowerKVM allows the kernel to intercept some RTAS calls from the
guest directly.  This is used to implement the more efficient in-kernel
XICS for example.  qemu is still responsible for assigning the RTAS token
numbers however, and needs to tell the kernel which RTAS function name is
assigned to a given token value.  This patch adds a convenience wrapper for
the KVM_PPC_RTAS_DEFINE_TOKEN ioctl() which is used for this purpose.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
---
 target-ppc/kvm.c     |   14 ++++++++++++++
 target-ppc/kvm_ppc.h |    7 +++++++
 2 files changed, 21 insertions(+)

diff --git a/target-ppc/kvm.c b/target-ppc/kvm.c
index c89dd58..33ddf63 100644
--- a/target-ppc/kvm.c
+++ b/target-ppc/kvm.c
@@ -1787,6 +1787,20 @@ static int kvm_ppc_register_host_cpu_type(void)
     return 0;
 }
 
+int kvmppc_define_rtas_token(uint32_t token, const char *function)
+{
+    struct kvm_rtas_token_args args = {
+        .token = token,
+    };
+
+    if (!kvm_check_extension(kvm_state, KVM_CAP_PPC_RTAS)) {
+        return -ENOENT;
+    }
+
+    strncpy(args.name, function, sizeof(args.name));
+
+    return kvm_vm_ioctl(kvm_state, KVM_PPC_RTAS_DEFINE_TOKEN, &args);
+}
 
 bool kvm_arch_stop_on_emulation_error(CPUState *cpu)
 {
diff --git a/target-ppc/kvm_ppc.h b/target-ppc/kvm_ppc.h
index 771cfbe..21939a8 100644
--- a/target-ppc/kvm_ppc.h
+++ b/target-ppc/kvm_ppc.h
@@ -38,6 +38,7 @@ uint64_t kvmppc_rma_size(uint64_t current_size, unsigned int hash_shift);
 #endif /* !CONFIG_USER_ONLY */
 int kvmppc_fixup_cpu(PowerPCCPU *cpu);
 bool kvmppc_has_cap_epr(void);
+int kvmppc_define_rtas_token(uint32_t token, const char *function);
 
 #else
 
@@ -159,6 +160,12 @@ static inline bool kvmppc_has_cap_epr(void)
 {
     return false;
 }
+
+static inline int kvmppc_define_rtas_token(uint32_t token,
+                                           const char *function)
+{
+    return -1;
+}
 #endif
 
 #ifndef CONFIG_KVM
-- 
1.7.10.4