Introduce Virtio-loopback epsilon release:

Epsilon release introduces a new compatibility layer which make virtio-loopback
design to work with QEMU and rust-vmm vhost-user backend without require any
changes.

Signed-off-by: Timos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>
Change-Id: I52e57563e08a7d0bdc002f8e928ee61ba0c53dd9

1 files changed, 66 insertions, 0 deletions

diff --git a/include/hw/pci/pci_bus.h b/include/hw/pci/pci_bus.h
new file mode 100644
index 000000000..347440d42
--- /dev/null
+++ b/include/hw/pci/pci_bus.h
@@ -0,0 +1,66 @@
+#ifndef QEMU_PCI_BUS_H
+#define QEMU_PCI_BUS_H
+
+#include "hw/pci/pci.h"
+
+/*
+ * PCI Bus datastructures.
+ *
+ * Do not access the following members directly;
+ * use accessor functions in pci.h
+ */
+
+struct PCIBusClass {
+    /*< private >*/
+    BusClass parent_class;
+    /*< public >*/
+
+    int (*bus_num)(PCIBus *bus);
+    uint16_t (*numa_node)(PCIBus *bus);
+};
+
+enum PCIBusFlags {
+    /* This bus is the root of a PCI domain */
+    PCI_BUS_IS_ROOT                                         = 0x0001,
+    /* PCIe extended configuration space is accessible on this bus */
+    PCI_BUS_EXTENDED_CONFIG_SPACE                           = 0x0002,
+};
+
+struct PCIBus {
+    BusState qbus;
+    enum PCIBusFlags flags;
+    PCIIOMMUFunc iommu_fn;
+    void *iommu_opaque;
+    uint8_t devfn_min;
+    uint32_t slot_reserved_mask;
+    pci_set_irq_fn set_irq;
+    pci_map_irq_fn map_irq;
+    pci_route_irq_fn route_intx_to_irq;
+    void *irq_opaque;
+    PCIDevice *devices[PCI_SLOT_MAX * PCI_FUNC_MAX];
+    PCIDevice *parent_dev;
+    MemoryRegion *address_space_mem;
+    MemoryRegion *address_space_io;
+
+    QLIST_HEAD(, PCIBus) child; /* this will be replaced by qdev later */
+    QLIST_ENTRY(PCIBus) sibling;/* this will be replaced by qdev later */
+
+    /* 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;
+
+    Notifier machine_done;
+};
+
+static inline bool pci_bus_is_root(PCIBus *bus)
+{
+    return !!(bus->flags & PCI_BUS_IS_ROOT);
+}
+
+static inline bool pci_bus_allows_extended_config_space(PCIBus *bus)
+{
+    return !!(bus->flags & PCI_BUS_EXTENDED_CONFIG_SPACE);
+}
+
+#endif /* QEMU_PCI_BUS_H */