[Qemu-devel] [PATCH 03/11] pc: check if KVM has enough memory slots for DIMM devices

[Igor Mammedov <imammedo@redhat.com>]

check amount of available KVM memory slots after all
devices were initialized and exit with error if
there isn't enough free memory slots for DIMMs.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
---
 hw/i386/pc.c | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index f6dfd9b..41d91fb 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -1125,6 +1125,36 @@ PcGuestInfo *pc_guest_info_init(ram_addr_t below_4g_mem_size,
     return guest_info;
 }
 
+static int pc_dimm_count(Object *obj, void *opaque)
+{
+    int *count = opaque;
+
+    if (object_dynamic_cast(obj, TYPE_PC_DIMM)) {
+        (*count)++;
+    }
+
+    object_child_foreach(obj, pc_dimm_count, opaque);
+    return 0;
+}
+
+static void pc_kvm_slot_check(Notifier *notifier, void *data)
+{
+    MachineState *ms = MACHINE(qdev_get_machine());
+    int free_slots = kvm_free_slot_count(ms);
+    int used_ram_slots = 0;
+
+    pc_dimm_count(OBJECT(ms), &used_ram_slots);
+    if ((ms->ram_slots - used_ram_slots) > free_slots) {
+        error_report("KVM doesn't support more than %d memory slots",
+                     kvm_free_slot_count(ms));
+        exit(EXIT_FAILURE);
+    }
+}
+
+static Notifier kvm_slot_check_on_machine_done = {
+                        .notify = pc_kvm_slot_check
+                     };
+
 /* setup pci memory address space mapping into system address space */
 void pc_pci_as_mapping_init(Object *owner, MemoryRegion *system_memory,
                             MemoryRegion *pci_address_space)
@@ -1269,6 +1299,8 @@ FWCfgState *pc_memory_init(MachineState *machine,
                            "hotplug-memory", hotplug_mem_size);
         memory_region_add_subregion(system_memory, pcms->hotplug_memory_base,
                                     &pcms->hotplug_memory);
+
+        qemu_add_machine_init_done_notifier(&kvm_slot_check_on_machine_done);
     }
 
     /* Initialize PC system firmware */
-- 
1.8.3.1