blob: f2640e505c4e794363d3df16bed27904dd1f9b60 [file] [log] [blame]
Andrew Scullb4b6d4a2019-01-02 15:54:55 +00001/* 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
6/*
7 * __virtio_test_bit - helper to test feature bits. For use by transports.
8 * Devices should normally use virtio_has_feature,
9 * which includes more checks.
10 * @vdev: the device
11 * @fbit: the feature bit
12 */
13static inline bool __virtio_test_bit(const struct virtio_device *vdev,
14 unsigned int fbit)
15{
16 return vdev->features & (1ULL << fbit);
17}
18
19/**
20 * __virtio_set_bit - helper to set feature bits. For use by transports.
21 * @vdev: the device
22 * @fbit: the feature bit
23 */
24static inline void __virtio_set_bit(struct virtio_device *vdev,
25 unsigned int fbit)
26{
27 vdev->features |= (1ULL << fbit);
28}
29
30/**
31 * __virtio_clear_bit - helper to clear feature bits. For use by transports.
32 * @vdev: the device
33 * @fbit: the feature bit
34 */
35static inline void __virtio_clear_bit(struct virtio_device *vdev,
36 unsigned int fbit)
37{
38 vdev->features &= ~(1ULL << fbit);
39}
40
41#define virtio_has_feature(dev, feature) \
42 (__virtio_test_bit((dev), feature))
43
44/**
Olivier Deprez157378f2022-04-04 15:47:50 +020045 * virtio_has_dma_quirk - determine whether this device has the DMA quirk
Andrew Scullb4b6d4a2019-01-02 15:54:55 +000046 * @vdev: the device
47 */
Olivier Deprez157378f2022-04-04 15:47:50 +020048static inline bool virtio_has_dma_quirk(const struct virtio_device *vdev)
Andrew Scullb4b6d4a2019-01-02 15:54:55 +000049{
50 /*
51 * Note the reverse polarity of the quirk feature (compared to most
52 * other features), this is for compatibility with legacy systems.
53 */
Olivier Deprez157378f2022-04-04 15:47:50 +020054 return !virtio_has_feature(vdev, VIRTIO_F_ACCESS_PLATFORM);
Andrew Scullb4b6d4a2019-01-02 15:54:55 +000055}
56
57static inline bool virtio_is_little_endian(struct virtio_device *vdev)
58{
59 return virtio_has_feature(vdev, VIRTIO_F_VERSION_1) ||
60 virtio_legacy_is_little_endian();
61}
62
63/* Memory accessors */
64static inline u16 virtio16_to_cpu(struct virtio_device *vdev, __virtio16 val)
65{
66 return __virtio16_to_cpu(virtio_is_little_endian(vdev), val);
67}
68
69static inline __virtio16 cpu_to_virtio16(struct virtio_device *vdev, u16 val)
70{
71 return __cpu_to_virtio16(virtio_is_little_endian(vdev), val);
72}
73
74static inline u32 virtio32_to_cpu(struct virtio_device *vdev, __virtio32 val)
75{
76 return __virtio32_to_cpu(virtio_is_little_endian(vdev), val);
77}
78
79static inline __virtio32 cpu_to_virtio32(struct virtio_device *vdev, u32 val)
80{
81 return __cpu_to_virtio32(virtio_is_little_endian(vdev), val);
82}
83
84static inline u64 virtio64_to_cpu(struct virtio_device *vdev, __virtio64 val)
85{
86 return __virtio64_to_cpu(virtio_is_little_endian(vdev), val);
87}
88
89static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val)
90{
91 return __cpu_to_virtio64(virtio_is_little_endian(vdev), val);
92}