Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
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 * @index: the zero-based ordinal number for this queue.
20 * @num_free: number of elements we expect to be able to fit.
21 *
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
24 * sg element.
25 */
26struct virtqueue {
27 struct list_head list;
28 void (*callback)(struct virtqueue *vq);
29 const char *name;
30 struct virtio_device *vdev;
31 unsigned int index;
32 unsigned int num_free;
33 void *priv;
34};
35
36int virtqueue_add_buf(struct virtqueue *vq,
37 struct scatterlist sg[],
38 unsigned int out_num,
39 unsigned int in_num,
40 void *data,
41 gfp_t gfp);
42
43void virtqueue_kick(struct virtqueue *vq);
44
45bool virtqueue_kick_prepare(struct virtqueue *vq);
46
47void virtqueue_notify(struct virtqueue *vq);
48
49void *virtqueue_get_buf(struct virtqueue *vq, unsigned int *len);
50
51void virtqueue_disable_cb(struct virtqueue *vq);
52
53bool virtqueue_enable_cb(struct virtqueue *vq);
54
55bool virtqueue_enable_cb_delayed(struct virtqueue *vq);
56
57void *virtqueue_detach_unused_buf(struct virtqueue *vq);
58
59unsigned int virtqueue_get_vring_size(struct virtqueue *vq);
60
61/* FIXME: Obsolete accessor, but required for virtio_net merge. */
62static inline unsigned int virtqueue_get_queue_index(struct virtqueue *vq)
63{
64 return vq->index;
65}
66
67/**
68 * virtio_device - representation of a device using virtio
69 * @index: unique position on the virtio bus
70 * @dev: underlying device.
71 * @id: the device type identification (used to match it with a driver).
72 * @config: the configuration ops for this device.
73 * @vqs: the list of virtqueues for this device.
74 * @features: the features supported by both driver and device.
75 * @priv: private pointer for the driver's use.
76 */
77struct virtio_device {
78 int index;
79 struct device dev;
80 struct virtio_device_id id;
81 struct virtio_config_ops *config;
82 struct list_head vqs;
83 /* Note that this is a Linux set_bit-style bitmap. */
84 unsigned long features[1];
85 void *priv;
86};
87
88static inline struct virtio_device *dev_to_virtio(struct device *_dev)
89{
90 return container_of(_dev, struct virtio_device, dev);
91}
92
93int register_virtio_device(struct virtio_device *dev);
94void unregister_virtio_device(struct virtio_device *dev);
95
96/**
97 * virtio_driver - operations for a virtio I/O driver
98 * @driver: underlying device driver (populate name and owner).
99 * @id_table: the ids serviced by this driver.
100 * @feature_table: an array of feature numbers supported by this driver.
101 * @feature_table_size: number of entries in the feature table array.
102 * @probe: the function to call when a device is found. Returns 0 or -errno.
103 * @remove: the function to call when a device is removed.
104 * @config_changed: optional function to call when the device configuration
105 * changes; may be called in interrupt context.
106 */
107struct virtio_driver {
108 struct device_driver driver;
109 const struct virtio_device_id *id_table;
110 const unsigned int *feature_table;
111 unsigned int feature_table_size;
112 int (*probe)(struct virtio_device *dev);
113 void (*scan)(struct virtio_device *dev);
114 void (*remove)(struct virtio_device *dev);
115 void (*config_changed)(struct virtio_device *dev);
116#ifdef CONFIG_PM
117 int (*freeze)(struct virtio_device *dev);
118 int (*restore)(struct virtio_device *dev);
119#endif
120};
121
122static inline struct virtio_driver *drv_to_virtio(struct device_driver *drv)
123{
124 return container_of(drv, struct virtio_driver, driver);
125}
126
127int register_virtio_driver(struct virtio_driver *drv);
128void unregister_virtio_driver(struct virtio_driver *drv);
129#endif /* _LINUX_VIRTIO_H */