diff options
Diffstat (limited to 'include/linux/virtio_pci.h')
| -rw-r--r-- | include/linux/virtio_pci.h | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/include/linux/virtio_pci.h b/include/linux/virtio_pci.h new file mode 100644 index 00000000000..9a3d7c48c62 --- /dev/null +++ b/include/linux/virtio_pci.h @@ -0,0 +1,72 @@ +/* + * Virtio PCI driver + * + * This module allows virtio devices to be used over a virtual PCI device. + * This can be used with QEMU based VMMs like KVM or Xen. + * + * Copyright IBM Corp. 2007 + * + * Authors: + * Anthony Liguori <aliguori@us.ibm.com> + * + * This header is BSD licensed so anyone can use the definitions to implement + * compatible drivers/servers. + */ + +#ifndef _LINUX_VIRTIO_PCI_H +#define _LINUX_VIRTIO_PCI_H + +#include <linux/virtio_config.h> + +/* A 32-bit r/o bitmask of the features supported by the host */ +#define VIRTIO_PCI_HOST_FEATURES 0 + +/* A 32-bit r/w bitmask of features activated by the guest */ +#define VIRTIO_PCI_GUEST_FEATURES 4 + +/* A 32-bit r/w PFN for the currently selected queue */ +#define VIRTIO_PCI_QUEUE_PFN 8 + +/* A 16-bit r/o queue size for the currently selected queue */ +#define VIRTIO_PCI_QUEUE_NUM 12 + +/* A 16-bit r/w queue selector */ +#define VIRTIO_PCI_QUEUE_SEL 14 + +/* A 16-bit r/w queue notifier */ +#define VIRTIO_PCI_QUEUE_NOTIFY 16 + +/* An 8-bit device status register. */ +#define VIRTIO_PCI_STATUS 18 + +/* An 8-bit r/o interrupt status register. Reading the value will return the + * current contents of the ISR and will also clear it. This is effectively + * a read-and-acknowledge. */ +#define VIRTIO_PCI_ISR 19 + +/* The bit of the ISR which indicates a device configuration change. */ +#define VIRTIO_PCI_ISR_CONFIG 0x2 + +/* MSI-X registers: only enabled if MSI-X is enabled. */ +/* A 16-bit vector for configuration changes. */ +#define VIRTIO_MSI_CONFIG_VECTOR 20 +/* A 16-bit vector for selected queue notifications. */ +#define VIRTIO_MSI_QUEUE_VECTOR 22 +/* Vector value used to disable MSI for queue */ +#define VIRTIO_MSI_NO_VECTOR 0xffff + +/* The remaining space is defined by each driver as the per-driver + * configuration space */ +#define VIRTIO_PCI_CONFIG(dev) ((dev)->msix_enabled ? 24 : 20) + +/* Virtio ABI version, this must match exactly */ +#define VIRTIO_PCI_ABI_VERSION 0 + +/* How many bits to shift physical queue address written to QUEUE_PFN. + * 12 is historical, and due to x86 page size. */ +#define VIRTIO_PCI_QUEUE_ADDR_SHIFT 12 + +/* The alignment to use between consumer and producer parts of vring. + * x86 pagesize again. */ +#define VIRTIO_PCI_VRING_ALIGN 4096 +#endif |