kvm: make one_reg helpers available for everyone

s390x introduced helper functions for getting/setting one_regs with
commit 860643b. However, nothing about these is s390-specific.

Alexey Kardashevskiy had already posted a general version, so let's
merge the two patches and massage the code a bit.

CC: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

include/sysemu/kvm.h

@@ -383,4 +383,24 @@ void kvm_init_irq_routing(KVMState *s);
  *          > 0: irq chip was created
  */
 int kvm_arch_irqchip_create(KVMState *s);
+
+/**
+ * kvm_set_one_reg - set a register value in KVM via KVM_SET_ONE_REG ioctl
+ * @id: The register ID
+ * @source: The pointer to the value to be set. It 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 *source);
+
+/**
+ * kvm_get_one_reg - get a register value from KVM via KVM_GET_ONE_REG ioctl
+ * @id: The register ID
+ * @target: The pointer where the value is to be stored. It 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 *target);
 #endif

kvm-all.c

@@ -2114,3 +2114,31 @@ int kvm_create_device(KVMState *s, uint64_t type, bool test)
 
     return test ? 0 : create_dev.fd;
 }
+
+int kvm_set_one_reg(CPUState *cs, uint64_t id, void *source)
+{
+    struct kvm_one_reg reg;
+    int r;
+
+    reg.id = id;
+    reg.addr = (uintptr_t) source;
+    r = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
+    if (r) {
+        trace_kvm_failed_reg_set(id, strerror(r));
+    }
+    return r;
+}
+
+int kvm_get_one_reg(CPUState *cs, uint64_t id, void *target)
+{
+    struct kvm_one_reg reg;
+    int r;
+
+    reg.id = id;
+    reg.addr = (uintptr_t) target;
+    r = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
+    if (r) {
+        trace_kvm_failed_reg_get(id, strerror(r));
+    }
+    return r;
+}

target-s390x/kvm.c

@@ -129,35 +129,6 @@ void kvm_arch_reset_vcpu(CPUState *cpu)
     }
 }
 
-static int kvm_set_one_reg(CPUState *cs, uint64_t id, void *source)
-{
-    struct kvm_one_reg reg;
-    int r;
-
-    reg.id = id;
-    reg.addr = (uint64_t) source;
-    r = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
-    if (r) {
-        trace_kvm_failed_reg_set(id, strerror(errno));
-    }
-    return r;
-}
-
-static int kvm_get_one_reg(CPUState *cs, uint64_t id, void *target)
-{
-    struct kvm_one_reg reg;
-    int r;
-
-    reg.id = id;
-    reg.addr = (uint64_t) target;
-    r = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
-    if (r) {
-        trace_kvm_failed_reg_get(id, strerror(errno));
-    }
-    return r;
-}
-
-
 int kvm_arch_put_registers(CPUState *cs, int level)
 {
     S390CPU *cpu = S390_CPU(cs);

trace-events

@@ -1230,6 +1230,8 @@ kvm_run_exit(int cpu_index, uint32_t reason) "cpu_index %d, reason %d"
 kvm_device_ioctl(int fd, int type, void *arg) "dev fd %d, type 0x%x, arg %p"
 kvm_failed_spr_set(int str, const char *msg) "Warning: Unable to set SPR %d to KVM: %s"
 kvm_failed_spr_get(int str, const char *msg) "Warning: Unable to retrieve SPR %d from KVM: %s"
+kvm_failed_reg_get(uint64_t id, const char *msg) "Warning: Unable to retrieve ONEREG %" PRIu64 " from KVM: %s"
+kvm_failed_reg_set(uint64_t id, const char *msg) "Warning: Unable to set ONEREG %" PRIu64 " to KVM: %s"
 
 # memory.c
 memory_region_ops_read(void *mr, uint64_t addr, uint64_t value, unsigned size) "mr %p addr %#"PRIx64" value %#"PRIx64" size %u"
@@ -1246,7 +1248,3 @@ xen_pv_mmio_write(uint64_t addr) "WARNING: write to Xen PV Device MMIO space (ad
 # hw/pci/pci_host.c
 pci_cfg_read(const char *dev, unsigned devid, unsigned fnid, unsigned offs, unsigned val) "%s %02u:%u @0x%x -> 0x%x"
 pci_cfg_write(const char *dev, unsigned devid, unsigned fnid, unsigned offs, unsigned val) "%s %02u:%u @0x%x <- 0x%x"
-
-# target-s390/kvm.c
-kvm_failed_reg_get(uint64_t id, const char *msg) "Warning: Unable to retrieve ONEREG %" PRIu64 " from KVM: %s"
-kvm_failed_reg_set(uint64_t id, const char *msg) "Warning: Unable to set ONEREG %" PRIu64 " to KVM: %s"