vfio: Add PCI device driver

Add PCI device support for VFIO.  PCI devices expose regions
for accessing config space, I/O port space, and MMIO areas
of the device.  PCI config access is virtualized in the kernel,
allowing us to ensure the integrity of the system, by preventing
various accesses while reducing duplicate support across various
userspace drivers.  I/O port supports read/write access while
MMIO also supports mmap of sufficiently sized regions.  Support
for INTx, MSI, and MSI-X interrupts are provided using eventfds to
userspace.

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

1 files changed, 26 insertions, 0 deletions

diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index acb046fd5b70..0a4f180a11d8 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -223,6 +223,7 @@ struct vfio_device_info {
         __u32   argsz;
         __u32   flags;
 #define VFIO_DEVICE_FLAGS_RESET (1 << 0)        /* Device supports reset */
+#define VFIO_DEVICE_FLAGS_PCI   (1 << 1)        /* vfio-pci device */
         __u32   num_regions;    /* Max region index + 1 */
         __u32   num_irqs;       /* Max IRQ index + 1 */
 };
@@ -364,6 +365,31 @@ struct vfio_irq_set {
  */
 #define VFIO_DEVICE_RESET               _IO(VFIO_TYPE, VFIO_BASE + 11)
 
+/*
+ * The VFIO-PCI bus driver makes use of the following fixed region and
+ * IRQ index mapping.  Unimplemented regions return a size of zero.
+ * Unimplemented IRQ types return a count of zero.
+ */
+
+enum {
+        VFIO_PCI_BAR0_REGION_INDEX,
+        VFIO_PCI_BAR1_REGION_INDEX,
+        VFIO_PCI_BAR2_REGION_INDEX,
+        VFIO_PCI_BAR3_REGION_INDEX,
+        VFIO_PCI_BAR4_REGION_INDEX,
+        VFIO_PCI_BAR5_REGION_INDEX,
+        VFIO_PCI_ROM_REGION_INDEX,
+        VFIO_PCI_CONFIG_REGION_INDEX,
+        VFIO_PCI_NUM_REGIONS
+};
+
+enum {
+        VFIO_PCI_INTX_IRQ_INDEX,
+        VFIO_PCI_MSI_IRQ_INDEX,
+        VFIO_PCI_MSIX_IRQ_INDEX,
+        VFIO_PCI_NUM_IRQS
+};
+
 /* -------- API for Type1 VFIO IOMMU -------- */
 
 /**