vfio: Generalize region support

Both platform and PCI vfio drivers create a "slow", I/O memory region
with one or more mmap memory regions overlayed when supported by the
device. Generalize this to a set of common helpers in the core that
pulls the region info from vfio, fills the region data, configures
slow mapping, and adds helpers for comleting the mmap, enable/disable,
and teardown.  This can be immediately used by the PCI MSI-X code,
which needs to mmap around the MSI-X vector table.

This also changes VFIORegion.mem to be dynamically allocated because
otherwise we don't know how the caller has allocated VFIORegion and
therefore don't know whether to unreference it to destroy the
MemoryRegion or not.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

1 files changed, 16 insertions, 7 deletions

diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index a147bd203e..eb0e1b0342 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -43,14 +43,21 @@ enum {
     VFIO_DEVICE_TYPE_PLATFORM = 1,
 };
 
+typedef struct VFIOMmap {
+    MemoryRegion mem;
+    void *mmap;
+    off_t offset;
+    size_t size;
+} VFIOMmap;
+
 typedef struct VFIORegion {
     struct VFIODevice *vbasedev;
     off_t fd_offset; /* offset of region within device fd */
-    MemoryRegion mem; /* slow, read/write access */
-    MemoryRegion mmap_mem; /* direct mapped access */
-    void *mmap;
+    MemoryRegion *mem; /* slow, read/write access */
     size_t size;
     uint32_t flags; /* VFIO region flags (rd/wr/mmap) */
+    uint32_t nr_mmaps;
+    VFIOMmap *mmaps;
     uint8_t nr; /* cache the region number for debug */
 } VFIORegion;
 
@@ -128,10 +135,12 @@ void vfio_region_write(void *opaque, hwaddr addr,
                            uint64_t data, unsigned size);
 uint64_t vfio_region_read(void *opaque,
                           hwaddr addr, unsigned size);
-int vfio_mmap_region(Object *vdev, VFIORegion *region,
-                     MemoryRegion *mem, MemoryRegion *submem,
-                     void **map, size_t size, off_t offset,
-                     const char *name);
+int vfio_region_setup(Object *obj, VFIODevice *vbasedev, VFIORegion *region,
+                      int index, const char *name);
+int vfio_region_mmap(VFIORegion *region);
+void vfio_region_mmaps_set_enabled(VFIORegion *region, bool enabled);
+void vfio_region_exit(VFIORegion *region);
+void vfio_region_finalize(VFIORegion *region);
 void vfio_reset_handler(void *opaque);
 VFIOGroup *vfio_get_group(int groupid, AddressSpace *as);
 void vfio_put_group(VFIOGroup *group);