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git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blob - include/linux/virtio.h
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 const struct virtio_config_ops
*config
;
77 /* Note that this is a Linux set_bit-style bitmap. */
78 unsigned long features
[1];
82 static inline struct virtio_device
*dev_to_virtio(struct device
*_dev
)
84 return container_of(_dev
, struct virtio_device
, dev
);
87 int register_virtio_device(struct virtio_device
*dev
);
88 void unregister_virtio_device(struct virtio_device
*dev
);
91 * virtio_driver - operations for a virtio I/O driver
92 * @driver: underlying device driver (populate name and owner).
93 * @id_table: the ids serviced by this driver.
94 * @feature_table: an array of feature numbers supported by this driver.
95 * @feature_table_size: number of entries in the feature table array.
96 * @probe: the function to call when a device is found. Returns 0 or -errno.
97 * @remove: the function to call when a device is removed.
98 * @config_changed: optional function to call when the device configuration
99 * changes; may be called in interrupt context.
101 struct virtio_driver
{
102 struct device_driver driver
;
103 const struct virtio_device_id
*id_table
;
104 const unsigned int *feature_table
;
105 unsigned int feature_table_size
;
106 int (*probe
)(struct virtio_device
*dev
);
107 void (*scan
)(struct virtio_device
*dev
);
108 void (*remove
)(struct virtio_device
*dev
);
109 void (*config_changed
)(struct virtio_device
*dev
);
111 int (*freeze
)(struct virtio_device
*dev
);
112 int (*restore
)(struct virtio_device
*dev
);
116 static inline struct virtio_driver
*drv_to_virtio(struct device_driver
*drv
)
118 return container_of(drv
, struct virtio_driver
, driver
);
121 int register_virtio_driver(struct virtio_driver
*drv
);
122 void unregister_virtio_driver(struct virtio_driver
*drv
);
124 /* module_virtio_driver() - Helper macro for drivers that don't do
125 * anything special in module init/exit. This eliminates a lot of
126 * boilerplate. Each module may only use this macro once, and
127 * calling it replaces module_init() and module_exit()
129 #define module_virtio_driver(__virtio_driver) \
130 module_driver(__virtio_driver, register_virtio_driver, \
131 unregister_virtio_driver)
132 #endif /* _LINUX_VIRTIO_H */