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1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef LINUX_VIRTIO_CONFIG_H3#define LINUX_VIRTIO_CONFIG_H4#include <linux/virtio_byteorder.h>5#include <linux/virtio.h>6#include <uapi/linux/virtio_config.h>7 8struct virtio_config_ops {9 int (*disable_vq_and_reset)(struct virtqueue *vq);10 int (*enable_vq_after_reset)(struct virtqueue *vq);11};12 13/*14 * __virtio_test_bit - helper to test feature bits. For use by transports.15 * Devices should normally use virtio_has_feature,16 * which includes more checks.17 * @vdev: the device18 * @fbit: the feature bit19 */20static inline bool __virtio_test_bit(const struct virtio_device *vdev,21 unsigned int fbit)22{23 return vdev->features & (1ULL << fbit);24}25 26/**27 * __virtio_set_bit - helper to set feature bits. For use by transports.28 * @vdev: the device29 * @fbit: the feature bit30 */31static inline void __virtio_set_bit(struct virtio_device *vdev,32 unsigned int fbit)33{34 vdev->features |= (1ULL << fbit);35}36 37/**38 * __virtio_clear_bit - helper to clear feature bits. For use by transports.39 * @vdev: the device40 * @fbit: the feature bit41 */42static inline void __virtio_clear_bit(struct virtio_device *vdev,43 unsigned int fbit)44{45 vdev->features &= ~(1ULL << fbit);46}47 48#define virtio_has_feature(dev, feature) \49 (__virtio_test_bit((dev), feature))50 51/**52 * virtio_has_dma_quirk - determine whether this device has the DMA quirk53 * @vdev: the device54 */55static inline bool virtio_has_dma_quirk(const struct virtio_device *vdev)56{57 /*58 * Note the reverse polarity of the quirk feature (compared to most59 * other features), this is for compatibility with legacy systems.60 */61 return !virtio_has_feature(vdev, VIRTIO_F_ACCESS_PLATFORM);62}63 64static inline bool virtio_is_little_endian(struct virtio_device *vdev)65{66 return virtio_has_feature(vdev, VIRTIO_F_VERSION_1) ||67 virtio_legacy_is_little_endian();68}69 70/* Memory accessors */71static inline u16 virtio16_to_cpu(struct virtio_device *vdev, __virtio16 val)72{73 return __virtio16_to_cpu(virtio_is_little_endian(vdev), val);74}75 76static inline __virtio16 cpu_to_virtio16(struct virtio_device *vdev, u16 val)77{78 return __cpu_to_virtio16(virtio_is_little_endian(vdev), val);79}80 81static inline u32 virtio32_to_cpu(struct virtio_device *vdev, __virtio32 val)82{83 return __virtio32_to_cpu(virtio_is_little_endian(vdev), val);84}85 86static inline __virtio32 cpu_to_virtio32(struct virtio_device *vdev, u32 val)87{88 return __cpu_to_virtio32(virtio_is_little_endian(vdev), val);89}90 91static inline u64 virtio64_to_cpu(struct virtio_device *vdev, __virtio64 val)92{93 return __virtio64_to_cpu(virtio_is_little_endian(vdev), val);94}95 96static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val)97{98 return __cpu_to_virtio64(virtio_is_little_endian(vdev), val);99}100 101#endif102