xref: /qemu/include/standard-headers/linux/virtio_config.h (revision 6f1e91f716a96651feae89dfd674b2ea3bf8e282)
1  #ifndef _LINUX_VIRTIO_CONFIG_H
2  #define _LINUX_VIRTIO_CONFIG_H
3  /* This header, excluding the #ifdef __KERNEL__ part, is BSD licensed so
4   * anyone can use the definitions to implement compatible drivers/servers.
5   *
6   * Redistribution and use in source and binary forms, with or without
7   * modification, are permitted provided that the following conditions
8   * are met:
9   * 1. Redistributions of source code must retain the above copyright
10   *    notice, this list of conditions and the following disclaimer.
11   * 2. Redistributions in binary form must reproduce the above copyright
12   *    notice, this list of conditions and the following disclaimer in the
13   *    documentation and/or other materials provided with the distribution.
14   * 3. Neither the name of IBM nor the names of its contributors
15   *    may be used to endorse or promote products derived from this software
16   *    without specific prior written permission.
17   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND
18   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20   * ARE DISCLAIMED.  IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
21   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27   * SUCH DAMAGE. */
28  
29  /* Virtio devices use a standardized configuration space to define their
30   * features and pass configuration information, but each implementation can
31   * store and access that space differently. */
32  #include "standard-headers/linux/types.h"
33  
34  /* Status byte for guest to report progress, and synchronize features. */
35  /* We have seen device and processed generic fields (VIRTIO_CONFIG_F_VIRTIO) */
36  #define VIRTIO_CONFIG_S_ACKNOWLEDGE	1
37  /* We have found a driver for the device. */
38  #define VIRTIO_CONFIG_S_DRIVER		2
39  /* Driver has used its parts of the config, and is happy */
40  #define VIRTIO_CONFIG_S_DRIVER_OK	4
41  /* Driver has finished configuring features */
42  #define VIRTIO_CONFIG_S_FEATURES_OK	8
43  /* Device entered invalid state, driver must reset it */
44  #define VIRTIO_CONFIG_S_NEEDS_RESET	0x40
45  /* We've given up on this device. */
46  #define VIRTIO_CONFIG_S_FAILED		0x80
47  
48  /*
49   * Virtio feature bits VIRTIO_TRANSPORT_F_START through
50   * VIRTIO_TRANSPORT_F_END are reserved for the transport
51   * being used (e.g. virtio_ring, virtio_pci etc.), the
52   * rest are per-device feature bits.
53   */
54  #define VIRTIO_TRANSPORT_F_START	28
55  #define VIRTIO_TRANSPORT_F_END		41
56  
57  #ifndef VIRTIO_CONFIG_NO_LEGACY
58  /* Do we get callbacks when the ring is completely used, even if we've
59   * suppressed them? */
60  #define VIRTIO_F_NOTIFY_ON_EMPTY	24
61  
62  /* Can the device handle any descriptor layout? */
63  #define VIRTIO_F_ANY_LAYOUT		27
64  #endif /* VIRTIO_CONFIG_NO_LEGACY */
65  
66  /* v1.0 compliant. */
67  #define VIRTIO_F_VERSION_1		32
68  
69  /*
70   * If clear - device has the platform DMA (e.g. IOMMU) bypass quirk feature.
71   * If set - use platform DMA tools to access the memory.
72   *
73   * Note the reverse polarity (compared to most other features),
74   * this is for compatibility with legacy systems.
75   */
76  #define VIRTIO_F_ACCESS_PLATFORM	33
77  /* Legacy name for VIRTIO_F_ACCESS_PLATFORM (for compatibility with old userspace) */
78  #define VIRTIO_F_IOMMU_PLATFORM		VIRTIO_F_ACCESS_PLATFORM
79  
80  /* This feature indicates support for the packed virtqueue layout. */
81  #define VIRTIO_F_RING_PACKED		34
82  
83  /*
84   * Inorder feature indicates that all buffers are used by the device
85   * in the same order in which they have been made available.
86   */
87  #define VIRTIO_F_IN_ORDER		35
88  
89  /*
90   * This feature indicates that memory accesses by the driver and the
91   * device are ordered in a way described by the platform.
92   */
93  #define VIRTIO_F_ORDER_PLATFORM		36
94  
95  /*
96   * Does the device support Single Root I/O Virtualization?
97   */
98  #define VIRTIO_F_SR_IOV			37
99  
100  /*
101   * This feature indicates that the driver can reset a queue individually.
102   */
103  #define VIRTIO_F_RING_RESET		40
104  #endif /* _LINUX_VIRTIO_CONFIG_H */
105