1/* SPDX-License-Identifier: GPL-2.0 */ 2#ifndef LINUX_VIRTIO_CONFIG_H 3#define LINUX_VIRTIO_CONFIG_H 4#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 device 18 * @fbit: the feature bit 19 */ 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 device 29 * @fbit: the feature bit 30 */ 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 device 40 * @fbit: the feature bit 41 */ 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 quirk 53 * @vdev: the device 54 */ 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 most 59 * 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#endif 102