vfio-pci: Add support for VGA region access
PCI defines display class VGA regions at I/O port address 0x3b0, 0x3c0
and MMIO address 0xa0000. As these are non-overlapping, we can ignore
the I/O port vs MMIO difference and expose them both in a single
region. We make use of the VGA arbiter around each access to
configure chipset access as necessary.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index 4758d1b..4f41f30 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -303,6 +303,15 @@
VFIO_PCI_BAR5_REGION_INDEX,
VFIO_PCI_ROM_REGION_INDEX,
VFIO_PCI_CONFIG_REGION_INDEX,
+ /*
+ * Expose VGA regions defined for PCI base class 03, subclass 00.
+ * This includes I/O port ranges 0x3b0 to 0x3bb and 0x3c0 to 0x3df
+ * as well as the MMIO range 0xa0000 to 0xbffff. Each implemented
+ * range is found at it's identity mapped offset from the region
+ * offset, for example 0x3b0 is region_info.offset + 0x3b0. Areas
+ * between described ranges are unimplemented.
+ */
+ VFIO_PCI_VGA_REGION_INDEX,
VFIO_PCI_NUM_REGIONS
};