vfio-pci: Add support for VGA region access

[platform/upstream/kernel-adaptation-pc.git] / drivers / vfio / pci / vfio_pci_rdwr.c

diff --git a/drivers/vfio/pci/vfio_pci_rdwr.c b/drivers/vfio/pci/vfio_pci_rdwr.c
index e9d78eb..210db24 100644 (file)
--- a/drivers/vfio/pci/vfio_pci_rdwr.c
+++ b/drivers/vfio/pci/vfio_pci_rdwr.c
@@ -17,6 +17,7 @@
 #include <linux/pci.h>
 #include <linux/uaccess.h>
 #include <linux/io.h>
+#include <linux/vgaarb.h>
 
 #include "vfio_pci_private.h"
 
@@ -175,3 +176,63 @@ ssize_t vfio_pci_bar_rw(struct vfio_pci_device *vdev, char __user *buf,
 
        return done;
 }
+
+ssize_t vfio_pci_vga_rw(struct vfio_pci_device *vdev, char __user *buf,
+                              size_t count, loff_t *ppos, bool iswrite)
+{
+       int ret;
+       loff_t off, pos = *ppos & VFIO_PCI_OFFSET_MASK;
+       void __iomem *iomem = NULL;
+       unsigned int rsrc;
+       bool is_ioport;
+       ssize_t done;
+
+       if (!vdev->has_vga)
+               return -EINVAL;
+
+       switch (pos) {
+       case 0xa0000 ... 0xbffff:
+               count = min(count, (size_t)(0xc0000 - pos));
+               iomem = ioremap_nocache(0xa0000, 0xbffff - 0xa0000 + 1);
+               off = pos - 0xa0000;
+               rsrc = VGA_RSRC_LEGACY_MEM;
+               is_ioport = false;
+               break;
+       case 0x3b0 ... 0x3bb:
+               count = min(count, (size_t)(0x3bc - pos));
+               iomem = ioport_map(0x3b0, 0x3bb - 0x3b0 + 1);
+               off = pos - 0x3b0;
+               rsrc = VGA_RSRC_LEGACY_IO;
+               is_ioport = true;
+               break;
+       case 0x3c0 ... 0x3df:
+               count = min(count, (size_t)(0x3e0 - pos));
+               iomem = ioport_map(0x3c0, 0x3df - 0x3c0 + 1);
+               off = pos - 0x3c0;
+               rsrc = VGA_RSRC_LEGACY_IO;
+               is_ioport = true;
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       if (!iomem)
+               return -ENOMEM;
+
+       ret = vga_get_interruptible(vdev->pdev, rsrc);
+       if (ret) {
+               is_ioport ? ioport_unmap(iomem) : iounmap(iomem);
+               return ret;
+       }
+
+       done = do_io_rw(iomem, buf, off, count, 0, 0, iswrite);
+
+       vga_put(vdev->pdev, rsrc);
+
+       is_ioport ? ioport_unmap(iomem) : iounmap(iomem);
+
+       if (done >= 0)
+               *ppos += done;
+
+       return done;
+}