[net-next-2.6.git] / include / linux / virtio_pci.h

/*
 * 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
Commit	Line	Data
3343660d AL	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	*
674bfc23 RR	12	* This header is BSD licensed so anyone can use the definitions to implement
674bfc23 RR	13	* compatible drivers/servers.
3343660d AL	14	*/
	15
	16	#ifndef _LINUX_VIRTIO_PCI_H
	17	#define _LINUX_VIRTIO_PCI_H
	18
	19	#include <linux/virtio_config.h>
	20
	21	/* A 32-bit r/o bitmask of the features supported by the host */
	22	#define VIRTIO_PCI_HOST_FEATURES 0
	23
	24	/* A 32-bit r/w bitmask of features activated by the guest */
	25	#define VIRTIO_PCI_GUEST_FEATURES 4
	26
	27	/* A 32-bit r/w PFN for the currently selected queue */
	28	#define VIRTIO_PCI_QUEUE_PFN 8
	29
	30	/* A 16-bit r/o queue size for the currently selected queue */
	31	#define VIRTIO_PCI_QUEUE_NUM 12
	32
	33	/* A 16-bit r/w queue selector */
	34	#define VIRTIO_PCI_QUEUE_SEL 14
	35
	36	/* A 16-bit r/w queue notifier */
	37	#define VIRTIO_PCI_QUEUE_NOTIFY 16
	38
	39	/* An 8-bit device status register. */
	40	#define VIRTIO_PCI_STATUS 18
	41
	42	/* An 8-bit r/o interrupt status register. Reading the value will return the
	43	* current contents of the ISR and will also clear it. This is effectively
	44	* a read-and-acknowledge. */
	45	#define VIRTIO_PCI_ISR 19
	46
	47	/* The bit of the ISR which indicates a device configuration change. */
	48	#define VIRTIO_PCI_ISR_CONFIG 0x2
	49
82af8ce8 MT	50	/* MSI-X registers: only enabled if MSI-X is enabled. */
	51	/* A 16-bit vector for configuration changes. */
	52	#define VIRTIO_MSI_CONFIG_VECTOR 20
	53	/* A 16-bit vector for selected queue notifications. */
	54	#define VIRTIO_MSI_QUEUE_VECTOR 22
	55	/* Vector value used to disable MSI for queue */
	56	#define VIRTIO_MSI_NO_VECTOR 0xffff
	57
3343660d AL	58	/* The remaining space is defined by each driver as the per-driver
3343660d AL	59	* configuration space */
82af8ce8	60	#define VIRTIO_PCI_CONFIG(dev) ((dev)->msix_enabled ? 24 : 20)
3343660d	61
55a7c066 AL	62	/* Virtio ABI version, this must match exactly */
55a7c066 AL	63	#define VIRTIO_PCI_ABI_VERSION 0
480daab4 RR	64
	65	/* How many bits to shift physical queue address written to QUEUE_PFN.
	66	* 12 is historical, and due to x86 page size. */
	67	#define VIRTIO_PCI_QUEUE_ADDR_SHIFT 12
498af147 RR	68
	69	/* The alignment to use between consumer and producer parts of vring.
	70	* x86 pagesize again. */
	71	#define VIRTIO_PCI_VRING_ALIGN 4096
3343660d	72	#endif