1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun #include <linux/virtio_byteorder.h>
3*4882a593Smuzhiyun #include <linux/virtio.h>
4*4882a593Smuzhiyun #include <uapi/linux/virtio_config.h>
5*4882a593Smuzhiyun
6*4882a593Smuzhiyun /*
7*4882a593Smuzhiyun * __virtio_test_bit - helper to test feature bits. For use by transports.
8*4882a593Smuzhiyun * Devices should normally use virtio_has_feature,
9*4882a593Smuzhiyun * which includes more checks.
10*4882a593Smuzhiyun * @vdev: the device
11*4882a593Smuzhiyun * @fbit: the feature bit
12*4882a593Smuzhiyun */
__virtio_test_bit(const struct virtio_device * vdev,unsigned int fbit)13*4882a593Smuzhiyun static inline bool __virtio_test_bit(const struct virtio_device *vdev,
14*4882a593Smuzhiyun unsigned int fbit)
15*4882a593Smuzhiyun {
16*4882a593Smuzhiyun return vdev->features & (1ULL << fbit);
17*4882a593Smuzhiyun }
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun /**
20*4882a593Smuzhiyun * __virtio_set_bit - helper to set feature bits. For use by transports.
21*4882a593Smuzhiyun * @vdev: the device
22*4882a593Smuzhiyun * @fbit: the feature bit
23*4882a593Smuzhiyun */
__virtio_set_bit(struct virtio_device * vdev,unsigned int fbit)24*4882a593Smuzhiyun static inline void __virtio_set_bit(struct virtio_device *vdev,
25*4882a593Smuzhiyun unsigned int fbit)
26*4882a593Smuzhiyun {
27*4882a593Smuzhiyun vdev->features |= (1ULL << fbit);
28*4882a593Smuzhiyun }
29*4882a593Smuzhiyun
30*4882a593Smuzhiyun /**
31*4882a593Smuzhiyun * __virtio_clear_bit - helper to clear feature bits. For use by transports.
32*4882a593Smuzhiyun * @vdev: the device
33*4882a593Smuzhiyun * @fbit: the feature bit
34*4882a593Smuzhiyun */
__virtio_clear_bit(struct virtio_device * vdev,unsigned int fbit)35*4882a593Smuzhiyun static inline void __virtio_clear_bit(struct virtio_device *vdev,
36*4882a593Smuzhiyun unsigned int fbit)
37*4882a593Smuzhiyun {
38*4882a593Smuzhiyun vdev->features &= ~(1ULL << fbit);
39*4882a593Smuzhiyun }
40*4882a593Smuzhiyun
41*4882a593Smuzhiyun #define virtio_has_feature(dev, feature) \
42*4882a593Smuzhiyun (__virtio_test_bit((dev), feature))
43*4882a593Smuzhiyun
44*4882a593Smuzhiyun /**
45*4882a593Smuzhiyun * virtio_has_dma_quirk - determine whether this device has the DMA quirk
46*4882a593Smuzhiyun * @vdev: the device
47*4882a593Smuzhiyun */
virtio_has_dma_quirk(const struct virtio_device * vdev)48*4882a593Smuzhiyun static inline bool virtio_has_dma_quirk(const struct virtio_device *vdev)
49*4882a593Smuzhiyun {
50*4882a593Smuzhiyun /*
51*4882a593Smuzhiyun * Note the reverse polarity of the quirk feature (compared to most
52*4882a593Smuzhiyun * other features), this is for compatibility with legacy systems.
53*4882a593Smuzhiyun */
54*4882a593Smuzhiyun return !virtio_has_feature(vdev, VIRTIO_F_ACCESS_PLATFORM);
55*4882a593Smuzhiyun }
56*4882a593Smuzhiyun
virtio_is_little_endian(struct virtio_device * vdev)57*4882a593Smuzhiyun static inline bool virtio_is_little_endian(struct virtio_device *vdev)
58*4882a593Smuzhiyun {
59*4882a593Smuzhiyun return virtio_has_feature(vdev, VIRTIO_F_VERSION_1) ||
60*4882a593Smuzhiyun virtio_legacy_is_little_endian();
61*4882a593Smuzhiyun }
62*4882a593Smuzhiyun
63*4882a593Smuzhiyun /* Memory accessors */
virtio16_to_cpu(struct virtio_device * vdev,__virtio16 val)64*4882a593Smuzhiyun static inline u16 virtio16_to_cpu(struct virtio_device *vdev, __virtio16 val)
65*4882a593Smuzhiyun {
66*4882a593Smuzhiyun return __virtio16_to_cpu(virtio_is_little_endian(vdev), val);
67*4882a593Smuzhiyun }
68*4882a593Smuzhiyun
cpu_to_virtio16(struct virtio_device * vdev,u16 val)69*4882a593Smuzhiyun static inline __virtio16 cpu_to_virtio16(struct virtio_device *vdev, u16 val)
70*4882a593Smuzhiyun {
71*4882a593Smuzhiyun return __cpu_to_virtio16(virtio_is_little_endian(vdev), val);
72*4882a593Smuzhiyun }
73*4882a593Smuzhiyun
virtio32_to_cpu(struct virtio_device * vdev,__virtio32 val)74*4882a593Smuzhiyun static inline u32 virtio32_to_cpu(struct virtio_device *vdev, __virtio32 val)
75*4882a593Smuzhiyun {
76*4882a593Smuzhiyun return __virtio32_to_cpu(virtio_is_little_endian(vdev), val);
77*4882a593Smuzhiyun }
78*4882a593Smuzhiyun
cpu_to_virtio32(struct virtio_device * vdev,u32 val)79*4882a593Smuzhiyun static inline __virtio32 cpu_to_virtio32(struct virtio_device *vdev, u32 val)
80*4882a593Smuzhiyun {
81*4882a593Smuzhiyun return __cpu_to_virtio32(virtio_is_little_endian(vdev), val);
82*4882a593Smuzhiyun }
83*4882a593Smuzhiyun
virtio64_to_cpu(struct virtio_device * vdev,__virtio64 val)84*4882a593Smuzhiyun static inline u64 virtio64_to_cpu(struct virtio_device *vdev, __virtio64 val)
85*4882a593Smuzhiyun {
86*4882a593Smuzhiyun return __virtio64_to_cpu(virtio_is_little_endian(vdev), val);
87*4882a593Smuzhiyun }
88*4882a593Smuzhiyun
cpu_to_virtio64(struct virtio_device * vdev,u64 val)89*4882a593Smuzhiyun static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val)
90*4882a593Smuzhiyun {
91*4882a593Smuzhiyun return __cpu_to_virtio64(virtio_is_little_endian(vdev), val);
92*4882a593Smuzhiyun }
93