LXR linux/tools/virtio/linux/virtio

   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
   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/**
  45 * virtio_has_dma_quirk - determine whether this device has the DMA quirk
  46 * @vdev: the device
  47 */
  48static inline bool virtio_has_dma_quirk(const struct virtio_device *vdev)
  49{
  50        /*
  51         * Note the reverse polarity of the quirk feature (compared to most
  52         * other features), this is for compatibility with legacy systems.
  53         */
  54        return !virtio_has_feature(vdev, VIRTIO_F_ACCESS_PLATFORM);
  55}
  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}
  93