include/linux/virtio_pci.h

   1 /*
   2  * Virtio PCI driver
   3  *
   4  * This module allows virtio devices to be used over a virtual PCI device.
   5  * This can be used with QEMU based VMMs like KVM or Xen.
   6  *
   7  * Copyright IBM Corp. 2007
   8  *
   9  * Authors:
  10  *  Anthony Liguori  <aliguori@us.ibm.com>
  11  *
  12  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  13  * See the COPYING file in the top-level directory.
  14  *
  15  */
  16
  17 #ifndef _LINUX_VIRTIO_PCI_H
  18 #define _LINUX_VIRTIO_PCI_H
  19
  20 #include <linux/virtio_config.h>
  21
  22 /* A 32-bit r/o bitmask of the features supported by the host */
  23 #define VIRTIO_PCI_HOST_FEATURES        0
  24
  25 /* A 32-bit r/w bitmask of features activated by the guest */
  26 #define VIRTIO_PCI_GUEST_FEATURES       4
  27
  28 /* A 32-bit r/w PFN for the currently selected queue */
  29 #define VIRTIO_PCI_QUEUE_PFN            8
  30
  31 /* A 16-bit r/o queue size for the currently selected queue */
  32 #define VIRTIO_PCI_QUEUE_NUM            12
  33
  34 /* A 16-bit r/w queue selector */
  35 #define VIRTIO_PCI_QUEUE_SEL            14
  36
  37 /* A 16-bit r/w queue notifier */
  38 #define VIRTIO_PCI_QUEUE_NOTIFY         16
  39
  40 /* An 8-bit device status register.  */
  41 #define VIRTIO_PCI_STATUS               18
  42
  43 /* An 8-bit r/o interrupt status register.  Reading the value will return the
  44  * current contents of the ISR and will also clear it.  This is effectively
  45  * a read-and-acknowledge. */
  46 #define VIRTIO_PCI_ISR                  19
  47
  48 /* The bit of the ISR which indicates a device configuration change. */
  49 #define VIRTIO_PCI_ISR_CONFIG           0x2
  50
  51 /* The remaining space is defined by each driver as the per-driver
  52  * configuration space */
  53 #define VIRTIO_PCI_CONFIG               20
  54
  55 /* Virtio ABI version, this must match exactly */
  56 #define VIRTIO_PCI_ABI_VERSION          0
  57 #endif