Migration: save/load PCI-Bus irq related state.kvm-56rc1

This irq state is being used to decide whether or not an interrupt
should be passed to the guest or not.

This state can be calculated from all the pci devices on that bus.
This commit may be reverted if we decide to calculate the irq related state
instead of save/load it.

Signed-off-by: Uri Lublin <uril@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

1 files changed, 36 insertions, 0 deletions

diff --git a/hw/pci.c b/hw/pci.c
index 774a8cf49..825b17b62 100644
--- a/hw/pci.c
+++ b/hw/pci.c
@@ -39,6 +39,7 @@ struct PCIBus {
     PCIBus *next;
     /* The bus IRQ state is the logical OR of the connected devices.
        Keep a count of the number of devices with raised IRQs.  */
+    int nirq;
     int irq_count[];
 };
 
@@ -49,16 +50,51 @@ target_phys_addr_t pci_mem_base;
 static int pci_irq_index;
 static PCIBus *first_bus;
 
+static void pcibus_save(QEMUFile *f, void *opaque)
+{
+    PCIBus *bus = (PCIBus *)opaque;
+    int i;
+
+    qemu_put_be32s(f, &bus->nirq);
+    for (i=0; i<bus->nirq; i++)
+        qemu_put_be32s(f, &bus->irq_count[i]);
+}
+
+static int  pcibus_load(QEMUFile *f, void *opaque, int version_id)
+{
+    PCIBus *bus = (PCIBus *)opaque;
+    int i, nirq;
+
+    if (version_id != 1)
+        return -EINVAL;
+
+    qemu_get_be32s(f, &nirq);
+    if (bus->nirq != nirq) {
+        fprintf(stderr, "pcibus_load: nirq mismatch: src=%d dst=%d\n",
+                nirq, bus->nirq);
+        return -EINVAL;
+    }
+
+    for (i=0; i<nirq; i++)
+        qemu_get_be32s(f, &bus->irq_count[i]);
+
+    return 0;
+}
+
 PCIBus *pci_register_bus(pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
                          qemu_irq *pic, int devfn_min, int nirq)
 {
     PCIBus *bus;
+    static int nbus = 0;
+
     bus = qemu_mallocz(sizeof(PCIBus) + (nirq * sizeof(int)));
     bus->set_irq = set_irq;
     bus->map_irq = map_irq;
     bus->irq_opaque = pic;
     bus->devfn_min = devfn_min;
+    bus->nirq = nirq;
     first_bus = bus;
+    register_savevm("PCIBUS", nbus++, 1, pcibus_save, pcibus_load, bus);
     return bus;
 }