virtio_config.h 2.5 KB

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