1 #ifndef _LINUX_VIRTIO_H
2 #define _LINUX_VIRTIO_H
3 /* Everything a virtio driver needs to work with any particular virtio
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>
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 * @index: the zero-based ordinal number for this queue.
20 * @num_free: number of elements we expect to be able to fit.
22 * A note on @num_free: with indirect buffers, each buffer needs one
23 * element in the queue, otherwise a buffer will need one element per
27 struct list_head list;
28 void (*callback)(struct virtqueue *vq);
30 struct virtio_device *vdev;
32 unsigned int num_free;
36 int virtqueue_add_buf(struct virtqueue *vq,
37 struct scatterlist sg[],
43 void virtqueue_kick(struct virtqueue *vq);
45 bool virtqueue_kick_prepare(struct virtqueue *vq);
47 void virtqueue_notify(struct virtqueue *vq);
49 void *virtqueue_get_buf(struct virtqueue *vq, unsigned int *len);
51 void virtqueue_disable_cb(struct virtqueue *vq);
53 bool virtqueue_enable_cb(struct virtqueue *vq);
55 bool virtqueue_enable_cb_delayed(struct virtqueue *vq);
57 void *virtqueue_detach_unused_buf(struct virtqueue *vq);
59 unsigned int virtqueue_get_vring_size(struct virtqueue *vq);
62 * virtio_device - representation of a device using virtio
63 * @index: unique position on the virtio bus
64 * @dev: underlying device.
65 * @id: the device type identification (used to match it with a driver).
66 * @config: the configuration ops for this device.
67 * @vqs: the list of virtqueues for this device.
68 * @features: the features supported by both driver and device.
69 * @priv: private pointer for the driver's use.
71 struct virtio_device {
74 struct virtio_device_id id;
75 struct virtio_config_ops *config;
77 /* Note that this is a Linux set_bit-style bitmap. */
78 unsigned long features[1];
82 #define dev_to_virtio(dev) container_of(dev, struct virtio_device, dev)
83 int register_virtio_device(struct virtio_device *dev);
84 void unregister_virtio_device(struct virtio_device *dev);
87 * virtio_driver - operations for a virtio I/O driver
88 * @driver: underlying device driver (populate name and owner).
89 * @id_table: the ids serviced by this driver.
90 * @feature_table: an array of feature numbers supported by this driver.
91 * @feature_table_size: number of entries in the feature table array.
92 * @probe: the function to call when a device is found. Returns 0 or -errno.
93 * @remove: the function to call when a device is removed.
94 * @config_changed: optional function to call when the device configuration
95 * changes; may be called in interrupt context.
97 struct virtio_driver {
98 struct device_driver driver;
99 const struct virtio_device_id *id_table;
100 const unsigned int *feature_table;
101 unsigned int feature_table_size;
102 int (*probe)(struct virtio_device *dev);
103 void (*scan)(struct virtio_device *dev);
104 void (*remove)(struct virtio_device *dev);
105 void (*config_changed)(struct virtio_device *dev);
107 int (*freeze)(struct virtio_device *dev);
108 int (*restore)(struct virtio_device *dev);
112 int register_virtio_driver(struct virtio_driver *drv);
113 void unregister_virtio_driver(struct virtio_driver *drv);
114 #endif /* _LINUX_VIRTIO_H */