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ec3d41c4 RR |
1 | #ifndef _LINUX_VIRTIO_CONFIG_H |
2 | #define _LINUX_VIRTIO_CONFIG_H | |
b4f68be6 | 3 | |
d2a7ddda | 4 | #include <linux/err.h> |
187f1882 | 5 | #include <linux/bug.h> |
72e61eb4 | 6 | #include <linux/virtio.h> |
607ca46e | 7 | #include <uapi/linux/virtio_config.h> |
ec3d41c4 RR |
8 | |
9 | /** | |
10 | * virtio_config_ops - operations for configuring a virtio device | |
a586d4f6 | 11 | * @get: read the value of a configuration field |
ec3d41c4 | 12 | * vdev: the virtio_device |
a586d4f6 | 13 | * offset: the offset of the configuration field |
ec3d41c4 | 14 | * buf: the buffer to write the field value into. |
a586d4f6 | 15 | * len: the length of the buffer |
a586d4f6 | 16 | * @set: write the value of a configuration field |
ec3d41c4 | 17 | * vdev: the virtio_device |
a586d4f6 | 18 | * offset: the offset of the configuration field |
ec3d41c4 | 19 | * buf: the buffer to read the field value from. |
a586d4f6 | 20 | * len: the length of the buffer |
ec3d41c4 RR |
21 | * @get_status: read the status byte |
22 | * vdev: the virtio_device | |
23 | * Returns the status byte | |
24 | * @set_status: write the status byte | |
25 | * vdev: the virtio_device | |
26 | * status: the new status byte | |
6e5aa7ef RR |
27 | * @reset: reset the device |
28 | * vdev: the virtio device | |
29 | * After this, status and feature negotiation must be done again | |
e6af578c MT |
30 | * Device must not be reset from its vq/config callbacks, or in |
31 | * parallel with being added/removed. | |
d2a7ddda | 32 | * @find_vqs: find virtqueues and instantiate them. |
ec3d41c4 | 33 | * vdev: the virtio_device |
d2a7ddda MT |
34 | * nvqs: the number of virtqueues to find |
35 | * vqs: on success, includes new virtqueues | |
36 | * callbacks: array of callbacks, for each virtqueue | |
6457f126 | 37 | * include a NULL entry for vqs that do not need a callback |
d2a7ddda | 38 | * names: array of virtqueue names (mainly for debugging) |
6457f126 | 39 | * include a NULL entry for vqs unused by driver |
d2a7ddda MT |
40 | * Returns 0 on success or error status |
41 | * @del_vqs: free virtqueues found by find_vqs(). | |
c45a6816 RR |
42 | * @get_features: get the array of feature bits for this device. |
43 | * vdev: the virtio_device | |
44 | * Returns the first 32 feature bits (all we currently need). | |
c624896e | 45 | * @finalize_features: confirm what device features we'll be using. |
c45a6816 | 46 | * vdev: the virtio_device |
c624896e RR |
47 | * This gives the final feature bits for the device: it can change |
48 | * the dev->feature bits if it wants. | |
66846048 RJ |
49 | * @bus_name: return the bus name associated with the device |
50 | * vdev: the virtio_device | |
51 | * This returns a pointer to the bus name a la pci_name from which | |
52 | * the caller can then copy. | |
75a0a52b | 53 | * @set_vq_affinity: set the affinity for a virtqueue. |
ec3d41c4 | 54 | */ |
d2a7ddda | 55 | typedef void vq_callback_t(struct virtqueue *); |
1842f23c | 56 | struct virtio_config_ops { |
a586d4f6 | 57 | void (*get)(struct virtio_device *vdev, unsigned offset, |
ec3d41c4 | 58 | void *buf, unsigned len); |
a586d4f6 | 59 | void (*set)(struct virtio_device *vdev, unsigned offset, |
ec3d41c4 RR |
60 | const void *buf, unsigned len); |
61 | u8 (*get_status)(struct virtio_device *vdev); | |
62 | void (*set_status)(struct virtio_device *vdev, u8 status); | |
6e5aa7ef | 63 | void (*reset)(struct virtio_device *vdev); |
d2a7ddda MT |
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 *); | |
c45a6816 | 69 | u32 (*get_features)(struct virtio_device *vdev); |
c624896e | 70 | void (*finalize_features)(struct virtio_device *vdev); |
66846048 | 71 | const char *(*bus_name)(struct virtio_device *vdev); |
75a0a52b | 72 | int (*set_vq_affinity)(struct virtqueue *vq, int cpu); |
ec3d41c4 RR |
73 | }; |
74 | ||
c45a6816 RR |
75 | /* If driver didn't advertise the feature, it will never appear. */ |
76 | void virtio_check_driver_offered_feature(const struct virtio_device *vdev, | |
77 | unsigned int fbit); | |
78 | ||
79 | /** | |
80 | * virtio_has_feature - helper to determine if this device has this feature. | |
81 | * @vdev: the device | |
82 | * @fbit: the feature bit | |
83 | */ | |
84 | static inline bool virtio_has_feature(const struct virtio_device *vdev, | |
85 | unsigned int fbit) | |
86 | { | |
87 | /* Did you forget to fix assumptions on max features? */ | |
1765e3a4 RR |
88 | if (__builtin_constant_p(fbit)) |
89 | BUILD_BUG_ON(fbit >= 32); | |
90 | else | |
91 | BUG_ON(fbit >= 32); | |
c45a6816 | 92 | |
ee006b35 MM |
93 | if (fbit < VIRTIO_TRANSPORT_F_START) |
94 | virtio_check_driver_offered_feature(vdev, fbit); | |
95 | ||
c45a6816 RR |
96 | return test_bit(fbit, vdev->features); |
97 | } | |
98 | ||
d2a7ddda MT |
99 | static inline |
100 | struct 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 | } | |
66846048 RJ |
111 | |
112 | static inline | |
113 | const 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 | ||
75a0a52b JW |
120 | /** |
121 | * virtqueue_set_affinity - setting affinity for a virtqueue | |
122 | * @vq: the virtqueue | |
123 | * @cpu: the cpu no. | |
124 | * | |
125 | * Pay attention the function are best-effort: the affinity hint may not be set | |
126 | * due to config support, irq type and sharing. | |
127 | * | |
128 | */ | |
129 | static inline | |
130 | int 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 | ||
0b90d062 RR |
138 | /* Config space accessors. */ |
139 | #define virtio_cread(vdev, structname, member, ptr) \ | |
140 | do { \ | |
141 | /* Must match the member's type, and be integer */ \ | |
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 | /* Config space accessors. */ | |
168 | #define virtio_cwrite(vdev, structname, member, ptr) \ | |
169 | do { \ | |
170 | /* Must match the member's type, and be integer */ \ | |
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 | ||
200 | static 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 | ||
207 | static 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 | ||
214 | static 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 | ||
220 | static 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 | ||
228 | static 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 | ||
234 | static 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 | ||
242 | static 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 | ||
248 | static 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 | ||
256 | static 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 | /* Conditional config space accessors. */ | |
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 | }) | |
75a0a52b | 272 | |
ec3d41c4 | 273 | #endif /* _LINUX_VIRTIO_CONFIG_H */ |