[Qemu-devel] [PATCH v8 6/7] s390x/cpu: Add error handling to cpu creation

[Matthew Rosato]

Check for and propogate errors during s390 cpu creation.

Signed-off-by: Matthew Rosato <address@hidden>
---
 hw/s390x/s390-virtio.c |  2 +-
 target-s390x/cpu-qom.h |  1 +
 target-s390x/cpu.c     | 56 +++++++++++++++++++++++++++++++++++++++++++++++++-
 target-s390x/cpu.h     |  2 ++
 target-s390x/helper.c  | 42 +++++++++++++++++++++++++++++++++++--
 5 files changed, 99 insertions(+), 4 deletions(-)

diff --git a/hw/s390x/s390-virtio.c b/hw/s390x/s390-virtio.c
index f00d6b4..2ab7b94 100644
--- a/hw/s390x/s390-virtio.c
+++ b/hw/s390x/s390-virtio.c
@@ -116,7 +116,7 @@ void s390_init_cpus(MachineState *machine)
     }
 
     for (i = 0; i < smp_cpus; i++) {
-        cpu_s390x_init(machine->cpu_model);
+        s390_new_cpu(machine->cpu_model, i, &error_fatal);
     }
 }
 
diff --git a/target-s390x/cpu-qom.h b/target-s390x/cpu-qom.h
index 56d82f2..1c90933 100644
--- a/target-s390x/cpu-qom.h
+++ b/target-s390x/cpu-qom.h
@@ -68,6 +68,7 @@ typedef struct S390CPU {
     /*< public >*/
 
     CPUS390XState env;
+    int64_t id;
     /* needed for live migration */
     void *irqstate;
     uint32_t irqstate_saved_size;
diff --git a/target-s390x/cpu.c b/target-s390x/cpu.c
index 76c8eaf..d1b7af9 100644
--- a/target-s390x/cpu.c
+++ b/target-s390x/cpu.c
@@ -30,8 +30,10 @@
 #include "qemu/error-report.h"
 #include "hw/hw.h"
 #include "trace.h"
+#include "qapi/visitor.h"
 #ifndef CONFIG_USER_ONLY
 #include "sysemu/arch_init.h"
+#include "sysemu/sysemu.h"
 #endif
 
 #define CR0_RESET       0xE0UL
@@ -199,16 +201,36 @@ static void s390_cpu_realizefn(DeviceState *dev, Error 
**errp)
     CPUS390XState *env = &cpu->env;
     Error *err = NULL;
 
+#if !defined(CONFIG_USER_ONLY)
+    if (cpu->id >= max_cpus) {
+        error_setg(errp, "Unable to add CPU: %" PRIi64
+                   ", max allowed: %d", cpu->id, max_cpus - 1);
+        return;
+    }
+#endif
+    if (cpu_exists(cpu->id)) {
+        error_setg(errp, "Unable to add CPU: %" PRIi64
+                   ", it already exists", cpu->id);
+        return;
+    }
+    if (cpu->id != scc->next_cpu_id) {
+        error_setg(errp, "Unable to add CPU: %" PRIi64
+                   ", The next available id is %" PRIi64, cpu->id,
+                   scc->next_cpu_id);
+        return;
+    }
+
     cpu_exec_init(cs, &err);
     if (err != NULL) {
         error_propagate(errp, err);
         return;
     }
+    scc->next_cpu_id = cs->cpu_index + 1;
 
 #if !defined(CONFIG_USER_ONLY)
     qemu_register_reset(s390_cpu_machine_reset_cb, cpu);
 #endif
-    env->cpu_num = scc->next_cpu_id++;
+    env->cpu_num = cpu->id;
     s390_cpu_gdb_init(cs);
     qemu_init_vcpu(cs);
 #if !defined(CONFIG_USER_ONLY)
@@ -220,6 +242,36 @@ static void s390_cpu_realizefn(DeviceState *dev, Error 
**errp)
     scc->parent_realize(dev, errp);
 }
 
+static void s390_cpu_set_id(Object *obj, Visitor *v, const char *name,
+                            void *opaque, Error **errp)
+{
+    S390CPU *cpu = S390_CPU(obj);
+    DeviceState *dev = DEVICE(obj);
+    const int64_t min = 0;
+    const int64_t max = UINT32_MAX;
+    Error *err = NULL;
+    int64_t value;
+
+    if (dev->realized) {
+        error_setg(errp, "Attempt to set property '%s' on '%s' after "
+                   "it was realized", name, object_get_typename(obj));
+        return;
+    }
+
+    visit_type_int(v, name, &value, &err);
+    if (err) {
+        error_propagate(errp, err);
+        return;
+    }
+    if (value < min || value > max) {
+        error_setg(errp, "Property %s.%s doesn't take value %" PRId64
+                   " (minimum: %" PRId64 ", maximum: %" PRId64 ")" ,
+                   object_get_typename(obj), name, value, min, max);
+        return;
+    }
+    cpu->id = value;
+}
+
 static void s390_cpu_initfn(Object *obj)
 {
     CPUState *cs = CPU(obj);
@@ -233,6 +285,8 @@ static void s390_cpu_initfn(Object *obj)
     cs->env_ptr = env;
     cs->halted = 1;
     cs->exception_index = EXCP_HLT;
+    object_property_add(OBJECT(cpu), "id", "int64_t", NULL, s390_cpu_set_id,
+                        NULL, NULL, NULL);
 #if !defined(CONFIG_USER_ONLY)
     qemu_get_timedate(&tm, 0);
     env->tod_offset = TOD_UNIX_EPOCH +
diff --git a/target-s390x/cpu.h b/target-s390x/cpu.h
index 49c8415..6667cc0 100644
--- a/target-s390x/cpu.h
+++ b/target-s390x/cpu.h
@@ -413,6 +413,8 @@ void trigger_pgm_exception(CPUS390XState *env, uint32_t 
code, uint32_t ilen);
 #endif
 
 S390CPU *cpu_s390x_init(const char *cpu_model);
+S390CPU *s390_new_cpu(const char *cpu_model, int64_t id, Error **errp);
+S390CPU *cpu_s390x_create(const char *cpu_model, Error **errp);
 void s390x_translate_init(void);
 int cpu_s390x_exec(CPUState *cpu);
 
diff --git a/target-s390x/helper.c b/target-s390x/helper.c
index 838bdd9..c48c816 100644
--- a/target-s390x/helper.c
+++ b/target-s390x/helper.c
@@ -30,6 +30,9 @@
 //#define DEBUG_S390
 //#define DEBUG_S390_STDOUT
 
+/* Use to track cpu ID for linux-user only */
+static int64_t next_cpu_id;
+
 #ifdef DEBUG_S390
 #ifdef DEBUG_S390_STDOUT
 #define DPRINTF(fmt, ...) \
@@ -65,14 +68,49 @@ void s390x_cpu_timer(void *opaque)
 }
 #endif
 
-S390CPU *cpu_s390x_init(const char *cpu_model)
+S390CPU *cpu_s390x_create(const char *cpu_model, Error **errp)
 {
     S390CPU *cpu;
 
     cpu = S390_CPU(object_new(TYPE_S390_CPU));
 
-    object_property_set_bool(OBJECT(cpu), true, "realized", NULL);
+    return cpu;
+}
+
+S390CPU *s390_new_cpu(const char *cpu_model, int64_t id, Error **errp)
+{
+    S390CPU *cpu = NULL;
+    Error *err = NULL;
+
+    cpu = cpu_s390x_create(cpu_model, &err);
+    if (err != NULL) {
+        goto out;
+    }
+
+    object_property_set_int(OBJECT(cpu), id, "id", &err);
+    if (err != NULL) {
+        goto out;
+    }
+    object_property_set_bool(OBJECT(cpu), true, "realized", &err);
 
+out:
+    if (err) {
+        error_propagate(errp, err);
+        object_unref(OBJECT(cpu));
+        cpu = NULL;
+    }
+    return cpu;
+}
+
+S390CPU *cpu_s390x_init(const char *cpu_model)
+{
+    Error *err = NULL;
+    S390CPU *cpu;
+
+    cpu = s390_new_cpu(cpu_model, next_cpu_id++, &err);
+    if (err) {
+        error_report_err(err);
+    }
     return cpu;
 }
 
-- 
1.9.1