Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#include <linux/virtio_byteorder.h>
3#include <linux/virtio.h>
4#include <uapi/linux/virtio_config.h>
5
6struct virtio_config_ops {
7 int (*disable_vq_and_reset)(struct virtqueue *vq);
8 int (*enable_vq_after_reset)(struct virtqueue *vq);
9};
10
11/*
12 * __virtio_test_bit - helper to test feature bits. For use by transports.
13 * Devices should normally use virtio_has_feature,
14 * which includes more checks.
15 * @vdev: the device
16 * @fbit: the feature bit
17 */
18static inline bool __virtio_test_bit(const struct virtio_device *vdev,
19 unsigned int fbit)
20{
21 return vdev->features & (1ULL << fbit);
22}
23
24/**
25 * __virtio_set_bit - helper to set feature bits. For use by transports.
26 * @vdev: the device
27 * @fbit: the feature bit
28 */
29static inline void __virtio_set_bit(struct virtio_device *vdev,
30 unsigned int fbit)
31{
32 vdev->features |= (1ULL << fbit);
33}
34
35/**
36 * __virtio_clear_bit - helper to clear feature bits. For use by transports.
37 * @vdev: the device
38 * @fbit: the feature bit
39 */
40static inline void __virtio_clear_bit(struct virtio_device *vdev,
41 unsigned int fbit)
42{
43 vdev->features &= ~(1ULL << fbit);
44}
45
46#define virtio_has_feature(dev, feature) \
47 (__virtio_test_bit((dev), feature))
48
49/**
50 * virtio_has_dma_quirk - determine whether this device has the DMA quirk
51 * @vdev: the device
52 */
53static inline bool virtio_has_dma_quirk(const struct virtio_device *vdev)
54{
55 /*
56 * Note the reverse polarity of the quirk feature (compared to most
57 * other features), this is for compatibility with legacy systems.
58 */
59 return !virtio_has_feature(vdev, VIRTIO_F_ACCESS_PLATFORM);
60}
61
62static inline bool virtio_is_little_endian(struct virtio_device *vdev)
63{
64 return virtio_has_feature(vdev, VIRTIO_F_VERSION_1) ||
65 virtio_legacy_is_little_endian();
66}
67
68/* Memory accessors */
69static inline u16 virtio16_to_cpu(struct virtio_device *vdev, __virtio16 val)
70{
71 return __virtio16_to_cpu(virtio_is_little_endian(vdev), val);
72}
73
74static inline __virtio16 cpu_to_virtio16(struct virtio_device *vdev, u16 val)
75{
76 return __cpu_to_virtio16(virtio_is_little_endian(vdev), val);
77}
78
79static inline u32 virtio32_to_cpu(struct virtio_device *vdev, __virtio32 val)
80{
81 return __virtio32_to_cpu(virtio_is_little_endian(vdev), val);
82}
83
84static inline __virtio32 cpu_to_virtio32(struct virtio_device *vdev, u32 val)
85{
86 return __cpu_to_virtio32(virtio_is_little_endian(vdev), val);
87}
88
89static inline u64 virtio64_to_cpu(struct virtio_device *vdev, __virtio64 val)
90{
91 return __virtio64_to_cpu(virtio_is_little_endian(vdev), val);
92}
93
94static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val)
95{
96 return __cpu_to_virtio64(virtio_is_little_endian(vdev), val);
97}