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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> |
eef960a0 | 7 | #include <linux/virtio_byteorder.h> |
607ca46e | 8 | #include <uapi/linux/virtio_config.h> |
ec3d41c4 RR |
9 | |
10 | /** | |
11 | * virtio_config_ops - operations for configuring a virtio device | |
a586d4f6 | 12 | * @get: read the value of a configuration field |
ec3d41c4 | 13 | * vdev: the virtio_device |
a586d4f6 | 14 | * offset: the offset of the configuration field |
ec3d41c4 | 15 | * buf: the buffer to write the field value into. |
a586d4f6 | 16 | * len: the length of the buffer |
a586d4f6 | 17 | * @set: write the value of a configuration field |
ec3d41c4 | 18 | * vdev: the virtio_device |
a586d4f6 | 19 | * offset: the offset of the configuration field |
ec3d41c4 | 20 | * buf: the buffer to read the field value from. |
a586d4f6 | 21 | * len: the length of the buffer |
d71de9ec MT |
22 | * @generation: config generation counter |
23 | * vdev: the virtio_device | |
24 | * Returns the config generation counter | |
ec3d41c4 RR |
25 | * @get_status: read the status byte |
26 | * vdev: the virtio_device | |
27 | * Returns the status byte | |
28 | * @set_status: write the status byte | |
29 | * vdev: the virtio_device | |
30 | * status: the new status byte | |
6e5aa7ef RR |
31 | * @reset: reset the device |
32 | * vdev: the virtio device | |
33 | * After this, status and feature negotiation must be done again | |
e6af578c MT |
34 | * Device must not be reset from its vq/config callbacks, or in |
35 | * parallel with being added/removed. | |
d2a7ddda | 36 | * @find_vqs: find virtqueues and instantiate them. |
ec3d41c4 | 37 | * vdev: the virtio_device |
d2a7ddda MT |
38 | * nvqs: the number of virtqueues to find |
39 | * vqs: on success, includes new virtqueues | |
40 | * callbacks: array of callbacks, for each virtqueue | |
6457f126 | 41 | * include a NULL entry for vqs that do not need a callback |
d2a7ddda | 42 | * names: array of virtqueue names (mainly for debugging) |
6457f126 | 43 | * include a NULL entry for vqs unused by driver |
d2a7ddda MT |
44 | * Returns 0 on success or error status |
45 | * @del_vqs: free virtqueues found by find_vqs(). | |
c45a6816 RR |
46 | * @get_features: get the array of feature bits for this device. |
47 | * vdev: the virtio_device | |
48 | * Returns the first 32 feature bits (all we currently need). | |
c624896e | 49 | * @finalize_features: confirm what device features we'll be using. |
c45a6816 | 50 | * vdev: the virtio_device |
c624896e RR |
51 | * This gives the final feature bits for the device: it can change |
52 | * the dev->feature bits if it wants. | |
5c609a5e | 53 | * Returns 0 on success or error status |
66846048 RJ |
54 | * @bus_name: return the bus name associated with the device |
55 | * vdev: the virtio_device | |
56 | * This returns a pointer to the bus name a la pci_name from which | |
57 | * the caller can then copy. | |
75a0a52b | 58 | * @set_vq_affinity: set the affinity for a virtqueue. |
ec3d41c4 | 59 | */ |
d2a7ddda | 60 | typedef void vq_callback_t(struct virtqueue *); |
1842f23c | 61 | struct virtio_config_ops { |
a586d4f6 | 62 | void (*get)(struct virtio_device *vdev, unsigned offset, |
ec3d41c4 | 63 | void *buf, unsigned len); |
a586d4f6 | 64 | void (*set)(struct virtio_device *vdev, unsigned offset, |
ec3d41c4 | 65 | const void *buf, unsigned len); |
d71de9ec | 66 | u32 (*generation)(struct virtio_device *vdev); |
ec3d41c4 RR |
67 | u8 (*get_status)(struct virtio_device *vdev); |
68 | void (*set_status)(struct virtio_device *vdev, u8 status); | |
6e5aa7ef | 69 | void (*reset)(struct virtio_device *vdev); |
d2a7ddda MT |
70 | int (*find_vqs)(struct virtio_device *, unsigned nvqs, |
71 | struct virtqueue *vqs[], | |
72 | vq_callback_t *callbacks[], | |
f7ad26ff | 73 | const char * const names[]); |
d2a7ddda | 74 | void (*del_vqs)(struct virtio_device *); |
d0254773 | 75 | u64 (*get_features)(struct virtio_device *vdev); |
5c609a5e | 76 | int (*finalize_features)(struct virtio_device *vdev); |
66846048 | 77 | const char *(*bus_name)(struct virtio_device *vdev); |
75a0a52b | 78 | int (*set_vq_affinity)(struct virtqueue *vq, int cpu); |
ec3d41c4 RR |
79 | }; |
80 | ||
c45a6816 RR |
81 | /* If driver didn't advertise the feature, it will never appear. */ |
82 | void virtio_check_driver_offered_feature(const struct virtio_device *vdev, | |
83 | unsigned int fbit); | |
84 | ||
85 | /** | |
d4024af5 MT |
86 | * __virtio_test_bit - helper to test feature bits. For use by transports. |
87 | * Devices should normally use virtio_has_feature, | |
88 | * which includes more checks. | |
c45a6816 RR |
89 | * @vdev: the device |
90 | * @fbit: the feature bit | |
91 | */ | |
d4024af5 MT |
92 | static inline bool __virtio_test_bit(const struct virtio_device *vdev, |
93 | unsigned int fbit) | |
94 | { | |
95 | /* Did you forget to fix assumptions on max features? */ | |
96 | if (__builtin_constant_p(fbit)) | |
d0254773 | 97 | BUILD_BUG_ON(fbit >= 64); |
d4024af5 | 98 | else |
d0254773 | 99 | BUG_ON(fbit >= 64); |
d4024af5 | 100 | |
d0254773 | 101 | return vdev->features & BIT_ULL(fbit); |
d4024af5 MT |
102 | } |
103 | ||
104 | /** | |
105 | * __virtio_set_bit - helper to set feature bits. For use by transports. | |
106 | * @vdev: the device | |
107 | * @fbit: the feature bit | |
108 | */ | |
109 | static inline void __virtio_set_bit(struct virtio_device *vdev, | |
110 | unsigned int fbit) | |
111 | { | |
112 | /* Did you forget to fix assumptions on max features? */ | |
113 | if (__builtin_constant_p(fbit)) | |
d0254773 | 114 | BUILD_BUG_ON(fbit >= 64); |
d4024af5 | 115 | else |
d0254773 | 116 | BUG_ON(fbit >= 64); |
d4024af5 | 117 | |
d0254773 | 118 | vdev->features |= BIT_ULL(fbit); |
d4024af5 MT |
119 | } |
120 | ||
121 | /** | |
122 | * __virtio_clear_bit - helper to clear feature bits. For use by transports. | |
123 | * @vdev: the device | |
124 | * @fbit: the feature bit | |
125 | */ | |
126 | static inline void __virtio_clear_bit(struct virtio_device *vdev, | |
c45a6816 RR |
127 | unsigned int fbit) |
128 | { | |
129 | /* Did you forget to fix assumptions on max features? */ | |
1765e3a4 | 130 | if (__builtin_constant_p(fbit)) |
d0254773 | 131 | BUILD_BUG_ON(fbit >= 64); |
1765e3a4 | 132 | else |
d0254773 | 133 | BUG_ON(fbit >= 64); |
c45a6816 | 134 | |
d0254773 | 135 | vdev->features &= ~BIT_ULL(fbit); |
d4024af5 MT |
136 | } |
137 | ||
138 | /** | |
139 | * virtio_has_feature - helper to determine if this device has this feature. | |
140 | * @vdev: the device | |
141 | * @fbit: the feature bit | |
142 | */ | |
143 | static inline bool virtio_has_feature(const struct virtio_device *vdev, | |
144 | unsigned int fbit) | |
145 | { | |
ee006b35 MM |
146 | if (fbit < VIRTIO_TRANSPORT_F_START) |
147 | virtio_check_driver_offered_feature(vdev, fbit); | |
148 | ||
d4024af5 | 149 | return __virtio_test_bit(vdev, fbit); |
c45a6816 RR |
150 | } |
151 | ||
d2a7ddda MT |
152 | static inline |
153 | struct virtqueue *virtio_find_single_vq(struct virtio_device *vdev, | |
154 | vq_callback_t *c, const char *n) | |
155 | { | |
156 | vq_callback_t *callbacks[] = { c }; | |
157 | const char *names[] = { n }; | |
158 | struct virtqueue *vq; | |
159 | int err = vdev->config->find_vqs(vdev, 1, &vq, callbacks, names); | |
160 | if (err < 0) | |
161 | return ERR_PTR(err); | |
162 | return vq; | |
163 | } | |
66846048 | 164 | |
3569db59 MT |
165 | /** |
166 | * virtio_device_ready - enable vq use in probe function | |
167 | * @vdev: the device | |
168 | * | |
169 | * Driver must call this to use vqs in the probe function. | |
170 | * | |
171 | * Note: vqs are enabled automatically after probe returns. | |
172 | */ | |
173 | static inline | |
174 | void virtio_device_ready(struct virtio_device *dev) | |
175 | { | |
176 | unsigned status = dev->config->get_status(dev); | |
177 | ||
178 | BUG_ON(status & VIRTIO_CONFIG_S_DRIVER_OK); | |
179 | dev->config->set_status(dev, status | VIRTIO_CONFIG_S_DRIVER_OK); | |
180 | } | |
181 | ||
66846048 RJ |
182 | static inline |
183 | const char *virtio_bus_name(struct virtio_device *vdev) | |
184 | { | |
185 | if (!vdev->config->bus_name) | |
186 | return "virtio"; | |
187 | return vdev->config->bus_name(vdev); | |
188 | } | |
189 | ||
75a0a52b JW |
190 | /** |
191 | * virtqueue_set_affinity - setting affinity for a virtqueue | |
192 | * @vq: the virtqueue | |
193 | * @cpu: the cpu no. | |
194 | * | |
195 | * Pay attention the function are best-effort: the affinity hint may not be set | |
196 | * due to config support, irq type and sharing. | |
197 | * | |
198 | */ | |
199 | static inline | |
200 | int virtqueue_set_affinity(struct virtqueue *vq, int cpu) | |
201 | { | |
202 | struct virtio_device *vdev = vq->vdev; | |
203 | if (vdev->config->set_vq_affinity) | |
204 | return vdev->config->set_vq_affinity(vq, cpu); | |
205 | return 0; | |
206 | } | |
207 | ||
cf561f0d GK |
208 | static inline bool virtio_is_little_endian(struct virtio_device *vdev) |
209 | { | |
7d824109 GK |
210 | return virtio_has_feature(vdev, VIRTIO_F_VERSION_1) || |
211 | virtio_legacy_is_little_endian(); | |
cf561f0d GK |
212 | } |
213 | ||
eef960a0 MT |
214 | /* Memory accessors */ |
215 | static inline u16 virtio16_to_cpu(struct virtio_device *vdev, __virtio16 val) | |
216 | { | |
cf561f0d | 217 | return __virtio16_to_cpu(virtio_is_little_endian(vdev), val); |
eef960a0 MT |
218 | } |
219 | ||
220 | static inline __virtio16 cpu_to_virtio16(struct virtio_device *vdev, u16 val) | |
221 | { | |
cf561f0d | 222 | return __cpu_to_virtio16(virtio_is_little_endian(vdev), val); |
eef960a0 MT |
223 | } |
224 | ||
225 | static inline u32 virtio32_to_cpu(struct virtio_device *vdev, __virtio32 val) | |
226 | { | |
cf561f0d | 227 | return __virtio32_to_cpu(virtio_is_little_endian(vdev), val); |
eef960a0 MT |
228 | } |
229 | ||
230 | static inline __virtio32 cpu_to_virtio32(struct virtio_device *vdev, u32 val) | |
231 | { | |
cf561f0d | 232 | return __cpu_to_virtio32(virtio_is_little_endian(vdev), val); |
eef960a0 MT |
233 | } |
234 | ||
235 | static inline u64 virtio64_to_cpu(struct virtio_device *vdev, __virtio64 val) | |
236 | { | |
cf561f0d | 237 | return __virtio64_to_cpu(virtio_is_little_endian(vdev), val); |
eef960a0 MT |
238 | } |
239 | ||
240 | static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val) | |
241 | { | |
cf561f0d | 242 | return __cpu_to_virtio64(virtio_is_little_endian(vdev), val); |
eef960a0 MT |
243 | } |
244 | ||
0b90d062 RR |
245 | /* Config space accessors. */ |
246 | #define virtio_cread(vdev, structname, member, ptr) \ | |
247 | do { \ | |
248 | /* Must match the member's type, and be integer */ \ | |
249 | if (!typecheck(typeof((((structname*)0)->member)), *(ptr))) \ | |
250 | (*ptr) = 1; \ | |
251 | \ | |
252 | switch (sizeof(*ptr)) { \ | |
253 | case 1: \ | |
254 | *(ptr) = virtio_cread8(vdev, \ | |
255 | offsetof(structname, member)); \ | |
256 | break; \ | |
257 | case 2: \ | |
258 | *(ptr) = virtio_cread16(vdev, \ | |
259 | offsetof(structname, member)); \ | |
260 | break; \ | |
261 | case 4: \ | |
262 | *(ptr) = virtio_cread32(vdev, \ | |
263 | offsetof(structname, member)); \ | |
264 | break; \ | |
265 | case 8: \ | |
266 | *(ptr) = virtio_cread64(vdev, \ | |
267 | offsetof(structname, member)); \ | |
268 | break; \ | |
269 | default: \ | |
270 | BUG(); \ | |
271 | } \ | |
272 | } while(0) | |
273 | ||
274 | /* Config space accessors. */ | |
275 | #define virtio_cwrite(vdev, structname, member, ptr) \ | |
276 | do { \ | |
277 | /* Must match the member's type, and be integer */ \ | |
278 | if (!typecheck(typeof((((structname*)0)->member)), *(ptr))) \ | |
279 | BUG_ON((*ptr) == 1); \ | |
280 | \ | |
281 | switch (sizeof(*ptr)) { \ | |
282 | case 1: \ | |
283 | virtio_cwrite8(vdev, \ | |
284 | offsetof(structname, member), \ | |
285 | *(ptr)); \ | |
286 | break; \ | |
287 | case 2: \ | |
288 | virtio_cwrite16(vdev, \ | |
289 | offsetof(structname, member), \ | |
290 | *(ptr)); \ | |
291 | break; \ | |
292 | case 4: \ | |
293 | virtio_cwrite32(vdev, \ | |
294 | offsetof(structname, member), \ | |
295 | *(ptr)); \ | |
296 | break; \ | |
297 | case 8: \ | |
298 | virtio_cwrite64(vdev, \ | |
299 | offsetof(structname, member), \ | |
300 | *(ptr)); \ | |
301 | break; \ | |
302 | default: \ | |
303 | BUG(); \ | |
304 | } \ | |
305 | } while(0) | |
306 | ||
d71de9ec MT |
307 | /* Read @count fields, @bytes each. */ |
308 | static inline void __virtio_cread_many(struct virtio_device *vdev, | |
309 | unsigned int offset, | |
310 | void *buf, size_t count, size_t bytes) | |
311 | { | |
312 | u32 old, gen = vdev->config->generation ? | |
313 | vdev->config->generation(vdev) : 0; | |
314 | int i; | |
315 | ||
316 | do { | |
317 | old = gen; | |
318 | ||
319 | for (i = 0; i < count; i++) | |
320 | vdev->config->get(vdev, offset + bytes * i, | |
321 | buf + i * bytes, bytes); | |
322 | ||
323 | gen = vdev->config->generation ? | |
324 | vdev->config->generation(vdev) : 0; | |
325 | } while (gen != old); | |
326 | } | |
327 | ||
0b90d062 RR |
328 | static inline void virtio_cread_bytes(struct virtio_device *vdev, |
329 | unsigned int offset, | |
330 | void *buf, size_t len) | |
331 | { | |
d71de9ec | 332 | __virtio_cread_many(vdev, offset, buf, len, 1); |
0b90d062 RR |
333 | } |
334 | ||
caa0e2d0 MT |
335 | static inline u8 virtio_cread8(struct virtio_device *vdev, unsigned int offset) |
336 | { | |
337 | u8 ret; | |
338 | vdev->config->get(vdev, offset, &ret, sizeof(ret)); | |
339 | return ret; | |
340 | } | |
341 | ||
0b90d062 RR |
342 | static inline void virtio_cwrite8(struct virtio_device *vdev, |
343 | unsigned int offset, u8 val) | |
344 | { | |
345 | vdev->config->set(vdev, offset, &val, sizeof(val)); | |
346 | } | |
347 | ||
348 | static inline u16 virtio_cread16(struct virtio_device *vdev, | |
349 | unsigned int offset) | |
350 | { | |
351 | u16 ret; | |
352 | vdev->config->get(vdev, offset, &ret, sizeof(ret)); | |
92e6d743 | 353 | return virtio16_to_cpu(vdev, (__force __virtio16)ret); |
0b90d062 RR |
354 | } |
355 | ||
356 | static inline void virtio_cwrite16(struct virtio_device *vdev, | |
357 | unsigned int offset, u16 val) | |
358 | { | |
92e6d743 | 359 | val = (__force u16)cpu_to_virtio16(vdev, val); |
0b90d062 RR |
360 | vdev->config->set(vdev, offset, &val, sizeof(val)); |
361 | } | |
362 | ||
363 | static inline u32 virtio_cread32(struct virtio_device *vdev, | |
364 | unsigned int offset) | |
365 | { | |
366 | u32 ret; | |
367 | vdev->config->get(vdev, offset, &ret, sizeof(ret)); | |
92e6d743 | 368 | return virtio32_to_cpu(vdev, (__force __virtio32)ret); |
0b90d062 RR |
369 | } |
370 | ||
371 | static inline void virtio_cwrite32(struct virtio_device *vdev, | |
372 | unsigned int offset, u32 val) | |
373 | { | |
92e6d743 | 374 | val = (__force u32)cpu_to_virtio32(vdev, val); |
0b90d062 RR |
375 | vdev->config->set(vdev, offset, &val, sizeof(val)); |
376 | } | |
377 | ||
378 | static inline u64 virtio_cread64(struct virtio_device *vdev, | |
379 | unsigned int offset) | |
380 | { | |
381 | u64 ret; | |
d71de9ec | 382 | __virtio_cread_many(vdev, offset, &ret, 1, sizeof(ret)); |
92e6d743 | 383 | return virtio64_to_cpu(vdev, (__force __virtio64)ret); |
0b90d062 RR |
384 | } |
385 | ||
386 | static inline void virtio_cwrite64(struct virtio_device *vdev, | |
387 | unsigned int offset, u64 val) | |
388 | { | |
92e6d743 | 389 | val = (__force u64)cpu_to_virtio64(vdev, val); |
0b90d062 RR |
390 | vdev->config->set(vdev, offset, &val, sizeof(val)); |
391 | } | |
392 | ||
393 | /* Conditional config space accessors. */ | |
394 | #define virtio_cread_feature(vdev, fbit, structname, member, ptr) \ | |
395 | ({ \ | |
396 | int _r = 0; \ | |
397 | if (!virtio_has_feature(vdev, fbit)) \ | |
398 | _r = -ENOENT; \ | |
399 | else \ | |
400 | virtio_cread((vdev), structname, member, ptr); \ | |
401 | _r; \ | |
402 | }) | |
75a0a52b | 403 | |
ec3d41c4 | 404 | #endif /* _LINUX_VIRTIO_CONFIG_H */ |