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 */ 13 static 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 */ 24 static 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 */ 35 static 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_iommu_quirk - determine whether this device has the iommu quirk 46 * @vdev: the device 47 */ 48 static inline bool virtio_has_iommu_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_IOMMU_PLATFORM); 55 } 56 57 static 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 */ 64 static 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 69 static 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 74 static 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 79 static 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 84 static 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 89 static 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