1 #ifndef _LINUX_VIRTIO_H 2 #define _LINUX_VIRTIO_H 3 /* Everything a virtio driver needs to work with any particular virtio 4 * implementation. */ 5 #include <linux/types.h> 6 #include <linux/scatterlist.h> 7 #include <linux/spinlock.h> 8 #include <linux/device.h> 9 #include <linux/mod_devicetable.h> 10 #include <linux/gfp.h> 11 12 /** 13 * virtqueue - a queue to register buffers for sending or receiving. 14 * @list: the chain of virtqueues for this device 15 * @callback: the function to call when buffers are consumed (can be NULL). 16 * @name: the name of this virtqueue (mainly for debugging) 17 * @vdev: the virtio device this queue was created for. 18 * @priv: a pointer for the virtqueue implementation to use. 19 */ 20 struct virtqueue { 21 struct list_head list; 22 void (*callback)(struct virtqueue *vq); 23 const char *name; 24 struct virtio_device *vdev; 25 void *priv; 26 }; 27 28 int virtqueue_add_buf(struct virtqueue *vq, 29 struct scatterlist sg[], 30 unsigned int out_num, 31 unsigned int in_num, 32 void *data, 33 gfp_t gfp); 34 35 void virtqueue_kick(struct virtqueue *vq); 36 37 bool virtqueue_kick_prepare(struct virtqueue *vq); 38 39 void virtqueue_notify(struct virtqueue *vq); 40 41 void *virtqueue_get_buf(struct virtqueue *vq, unsigned int *len); 42 43 void virtqueue_disable_cb(struct virtqueue *vq); 44 45 bool virtqueue_enable_cb(struct virtqueue *vq); 46 47 bool virtqueue_enable_cb_delayed(struct virtqueue *vq); 48 49 void *virtqueue_detach_unused_buf(struct virtqueue *vq); 50 51 unsigned int virtqueue_get_vring_size(struct virtqueue *vq); 52 53 /** 54 * virtio_device - representation of a device using virtio 55 * @index: unique position on the virtio bus 56 * @dev: underlying device. 57 * @id: the device type identification (used to match it with a driver). 58 * @config: the configuration ops for this device. 59 * @vqs: the list of virtqueues for this device. 60 * @features: the features supported by both driver and device. 61 * @priv: private pointer for the driver's use. 62 */ 63 struct virtio_device { 64 int index; 65 struct device dev; 66 struct virtio_device_id id; 67 struct virtio_config_ops *config; 68 struct list_head vqs; 69 /* Note that this is a Linux set_bit-style bitmap. */ 70 unsigned long features[1]; 71 void *priv; 72 }; 73 74 #define dev_to_virtio(dev) container_of(dev, struct virtio_device, dev) 75 int register_virtio_device(struct virtio_device *dev); 76 void unregister_virtio_device(struct virtio_device *dev); 77 78 /** 79 * virtio_driver - operations for a virtio I/O driver 80 * @driver: underlying device driver (populate name and owner). 81 * @id_table: the ids serviced by this driver. 82 * @feature_table: an array of feature numbers supported by this driver. 83 * @feature_table_size: number of entries in the feature table array. 84 * @probe: the function to call when a device is found. Returns 0 or -errno. 85 * @remove: the function to call when a device is removed. 86 * @config_changed: optional function to call when the device configuration 87 * changes; may be called in interrupt context. 88 */ 89 struct virtio_driver { 90 struct device_driver driver; 91 const struct virtio_device_id *id_table; 92 const unsigned int *feature_table; 93 unsigned int feature_table_size; 94 int (*probe)(struct virtio_device *dev); 95 void (*remove)(struct virtio_device *dev); 96 void (*config_changed)(struct virtio_device *dev); 97 #ifdef CONFIG_PM 98 int (*freeze)(struct virtio_device *dev); 99 int (*thaw)(struct virtio_device *dev); 100 int (*restore)(struct virtio_device *dev); 101 #endif 102 }; 103 104 int register_virtio_driver(struct virtio_driver *drv); 105 void unregister_virtio_driver(struct virtio_driver *drv); 106 #endif /* _LINUX_VIRTIO_H */ 107