93 строки
2.5 KiB
C
93 строки
2.5 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#include <linux/virtio_byteorder.h>
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#include <linux/virtio.h>
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#include <uapi/linux/virtio_config.h>
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/*
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* __virtio_test_bit - helper to test feature bits. For use by transports.
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* Devices should normally use virtio_has_feature,
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* which includes more checks.
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* @vdev: the device
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* @fbit: the feature bit
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*/
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static inline bool __virtio_test_bit(const struct virtio_device *vdev,
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unsigned int fbit)
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{
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return vdev->features & (1ULL << fbit);
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}
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/**
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* __virtio_set_bit - helper to set feature bits. For use by transports.
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* @vdev: the device
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* @fbit: the feature bit
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*/
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static inline void __virtio_set_bit(struct virtio_device *vdev,
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unsigned int fbit)
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{
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vdev->features |= (1ULL << fbit);
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}
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/**
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* __virtio_clear_bit - helper to clear feature bits. For use by transports.
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* @vdev: the device
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* @fbit: the feature bit
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*/
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static inline void __virtio_clear_bit(struct virtio_device *vdev,
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unsigned int fbit)
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{
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vdev->features &= ~(1ULL << fbit);
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}
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#define virtio_has_feature(dev, feature) \
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(__virtio_test_bit((dev), feature))
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/**
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* virtio_has_dma_quirk - determine whether this device has the DMA quirk
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* @vdev: the device
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*/
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static inline bool virtio_has_dma_quirk(const struct virtio_device *vdev)
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{
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/*
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* Note the reverse polarity of the quirk feature (compared to most
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* other features), this is for compatibility with legacy systems.
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*/
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return !virtio_has_feature(vdev, VIRTIO_F_ACCESS_PLATFORM);
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}
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static inline bool virtio_is_little_endian(struct virtio_device *vdev)
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{
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return virtio_has_feature(vdev, VIRTIO_F_VERSION_1) ||
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virtio_legacy_is_little_endian();
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}
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/* Memory accessors */
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static inline u16 virtio16_to_cpu(struct virtio_device *vdev, __virtio16 val)
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{
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return __virtio16_to_cpu(virtio_is_little_endian(vdev), val);
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}
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static inline __virtio16 cpu_to_virtio16(struct virtio_device *vdev, u16 val)
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{
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return __cpu_to_virtio16(virtio_is_little_endian(vdev), val);
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}
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static inline u32 virtio32_to_cpu(struct virtio_device *vdev, __virtio32 val)
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{
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return __virtio32_to_cpu(virtio_is_little_endian(vdev), val);
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}
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static inline __virtio32 cpu_to_virtio32(struct virtio_device *vdev, u32 val)
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{
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return __cpu_to_virtio32(virtio_is_little_endian(vdev), val);
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}
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static inline u64 virtio64_to_cpu(struct virtio_device *vdev, __virtio64 val)
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{
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return __virtio64_to_cpu(virtio_is_little_endian(vdev), val);
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}
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static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val)
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{
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return __cpu_to_virtio64(virtio_is_little_endian(vdev), val);
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}
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