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>
This commit is contained in:
Alex Williamson
2013-02-18 10:11:13 -07:00
parent 2dd1194833
commit 84237a826b
5 changed files with 102 additions and 0 deletions

View File

@@ -84,6 +84,11 @@ static int vfio_pci_enable(struct vfio_pci_device *vdev)
} else
vdev->msix_bar = 0xFF;
#ifdef CONFIG_VFIO_PCI_VGA
if ((pdev->class >> 8) == PCI_CLASS_DISPLAY_VGA)
vdev->has_vga = true;
#endif
return 0;
}
@@ -285,6 +290,16 @@ static long vfio_pci_ioctl(void *device_data,
info.flags = VFIO_REGION_INFO_FLAG_READ;
break;
}
case VFIO_PCI_VGA_REGION_INDEX:
if (!vdev->has_vga)
return -EINVAL;
info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
info.size = 0xc0000;
info.flags = VFIO_REGION_INFO_FLAG_READ |
VFIO_REGION_INFO_FLAG_WRITE;
break;
default:
return -EINVAL;
}
@@ -386,6 +401,9 @@ static ssize_t vfio_pci_rw(void *device_data, char __user *buf,
case VFIO_PCI_BAR0_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX:
return vfio_pci_bar_rw(vdev, buf, count, ppos, iswrite);
case VFIO_PCI_VGA_REGION_INDEX:
return vfio_pci_vga_rw(vdev, buf, count, ppos, iswrite);
}
return -EINVAL;