1#ifndef _LINUX_VIRTIO_CONFIG_H
2#define _LINUX_VIRTIO_CONFIG_H
3
4#include <linux/err.h>
5#include <linux/bug.h>
6#include <linux/virtio.h>
7#include <uapi/linux/virtio_config.h>
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55typedef void vq_callback_t(struct virtqueue *);
56struct virtio_config_ops {
57 void (*get)(struct virtio_device *vdev, unsigned offset,
58 void *buf, unsigned len);
59 void (*set)(struct virtio_device *vdev, unsigned offset,
60 const void *buf, unsigned len);
61 u8 (*get_status)(struct virtio_device *vdev);
62 void (*set_status)(struct virtio_device *vdev, u8 status);
63 void (*reset)(struct virtio_device *vdev);
64 int (*find_vqs)(struct virtio_device *, unsigned nvqs,
65 struct virtqueue *vqs[],
66 vq_callback_t *callbacks[],
67 const char *names[]);
68 void (*del_vqs)(struct virtio_device *);
69 u32 (*get_features)(struct virtio_device *vdev);
70 void (*finalize_features)(struct virtio_device *vdev);
71 const char *(*bus_name)(struct virtio_device *vdev);
72 int (*set_vq_affinity)(struct virtqueue *vq, int cpu);
73};
74
75
76void virtio_check_driver_offered_feature(const struct virtio_device *vdev,
77 unsigned int fbit);
78
79
80
81
82
83
84static inline bool virtio_has_feature(const struct virtio_device *vdev,
85 unsigned int fbit)
86{
87
88 if (__builtin_constant_p(fbit))
89 BUILD_BUG_ON(fbit >= 32);
90 else
91 BUG_ON(fbit >= 32);
92
93 if (fbit < VIRTIO_TRANSPORT_F_START)
94 virtio_check_driver_offered_feature(vdev, fbit);
95
96 return test_bit(fbit, vdev->features);
97}
98
99static inline
100struct virtqueue *virtio_find_single_vq(struct virtio_device *vdev,
101 vq_callback_t *c, const char *n)
102{
103 vq_callback_t *callbacks[] = { c };
104 const char *names[] = { n };
105 struct virtqueue *vq;
106 int err = vdev->config->find_vqs(vdev, 1, &vq, callbacks, names);
107 if (err < 0)
108 return ERR_PTR(err);
109 return vq;
110}
111
112static inline
113const char *virtio_bus_name(struct virtio_device *vdev)
114{
115 if (!vdev->config->bus_name)
116 return "virtio";
117 return vdev->config->bus_name(vdev);
118}
119
120
121
122
123
124
125
126
127
128
129static inline
130int virtqueue_set_affinity(struct virtqueue *vq, int cpu)
131{
132 struct virtio_device *vdev = vq->vdev;
133 if (vdev->config->set_vq_affinity)
134 return vdev->config->set_vq_affinity(vq, cpu);
135 return 0;
136}
137
138
139#define virtio_cread(vdev, structname, member, ptr) \
140 do { \
141 \
142 if (!typecheck(typeof((((structname*)0)->member)), *(ptr))) \
143 (*ptr) = 1; \
144 \
145 switch (sizeof(*ptr)) { \
146 case 1: \
147 *(ptr) = virtio_cread8(vdev, \
148 offsetof(structname, member)); \
149 break; \
150 case 2: \
151 *(ptr) = virtio_cread16(vdev, \
152 offsetof(structname, member)); \
153 break; \
154 case 4: \
155 *(ptr) = virtio_cread32(vdev, \
156 offsetof(structname, member)); \
157 break; \
158 case 8: \
159 *(ptr) = virtio_cread64(vdev, \
160 offsetof(structname, member)); \
161 break; \
162 default: \
163 BUG(); \
164 } \
165 } while(0)
166
167
168#define virtio_cwrite(vdev, structname, member, ptr) \
169 do { \
170 \
171 if (!typecheck(typeof((((structname*)0)->member)), *(ptr))) \
172 BUG_ON((*ptr) == 1); \
173 \
174 switch (sizeof(*ptr)) { \
175 case 1: \
176 virtio_cwrite8(vdev, \
177 offsetof(structname, member), \
178 *(ptr)); \
179 break; \
180 case 2: \
181 virtio_cwrite16(vdev, \
182 offsetof(structname, member), \
183 *(ptr)); \
184 break; \
185 case 4: \
186 virtio_cwrite32(vdev, \
187 offsetof(structname, member), \
188 *(ptr)); \
189 break; \
190 case 8: \
191 virtio_cwrite64(vdev, \
192 offsetof(structname, member), \
193 *(ptr)); \
194 break; \
195 default: \
196 BUG(); \
197 } \
198 } while(0)
199
200static inline u8 virtio_cread8(struct virtio_device *vdev, unsigned int offset)
201{
202 u8 ret;
203 vdev->config->get(vdev, offset, &ret, sizeof(ret));
204 return ret;
205}
206
207static inline void virtio_cread_bytes(struct virtio_device *vdev,
208 unsigned int offset,
209 void *buf, size_t len)
210{
211 vdev->config->get(vdev, offset, buf, len);
212}
213
214static inline void virtio_cwrite8(struct virtio_device *vdev,
215 unsigned int offset, u8 val)
216{
217 vdev->config->set(vdev, offset, &val, sizeof(val));
218}
219
220static inline u16 virtio_cread16(struct virtio_device *vdev,
221 unsigned int offset)
222{
223 u16 ret;
224 vdev->config->get(vdev, offset, &ret, sizeof(ret));
225 return ret;
226}
227
228static inline void virtio_cwrite16(struct virtio_device *vdev,
229 unsigned int offset, u16 val)
230{
231 vdev->config->set(vdev, offset, &val, sizeof(val));
232}
233
234static inline u32 virtio_cread32(struct virtio_device *vdev,
235 unsigned int offset)
236{
237 u32 ret;
238 vdev->config->get(vdev, offset, &ret, sizeof(ret));
239 return ret;
240}
241
242static inline void virtio_cwrite32(struct virtio_device *vdev,
243 unsigned int offset, u32 val)
244{
245 vdev->config->set(vdev, offset, &val, sizeof(val));
246}
247
248static inline u64 virtio_cread64(struct virtio_device *vdev,
249 unsigned int offset)
250{
251 u64 ret;
252 vdev->config->get(vdev, offset, &ret, sizeof(ret));
253 return ret;
254}
255
256static inline void virtio_cwrite64(struct virtio_device *vdev,
257 unsigned int offset, u64 val)
258{
259 vdev->config->set(vdev, offset, &val, sizeof(val));
260}
261
262
263#define virtio_cread_feature(vdev, fbit, structname, member, ptr) \
264 ({ \
265 int _r = 0; \
266 if (!virtio_has_feature(vdev, fbit)) \
267 _r = -ENOENT; \
268 else \
269 virtio_cread((vdev), structname, member, ptr); \
270 _r; \
271 })
272
273#endif
274