1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef _LINUX_VIRTIO_CONFIG_H |
3 | #define _LINUX_VIRTIO_CONFIG_H |
4 | |
5 | #include <linux/err.h> |
6 | #include <linux/bug.h> |
7 | #include <linux/virtio.h> |
8 | #include <linux/virtio_byteorder.h> |
9 | #include <linux/compiler_types.h> |
10 | #include <uapi/linux/virtio_config.h> |
11 | |
12 | struct irq_affinity; |
13 | |
14 | struct virtio_shm_region { |
15 | u64 addr; |
16 | u64 len; |
17 | }; |
18 | |
19 | typedef void vq_callback_t(struct virtqueue *); |
20 | |
21 | /** |
22 | * struct virtio_config_ops - operations for configuring a virtio device |
23 | * Note: Do not assume that a transport implements all of the operations |
24 | * getting/setting a value as a simple read/write! Generally speaking, |
25 | * any of @get/@set, @get_status/@set_status, or @get_features/ |
26 | * @finalize_features are NOT safe to be called from an atomic |
27 | * context. |
28 | * @get: read the value of a configuration field |
29 | * vdev: the virtio_device |
30 | * offset: the offset of the configuration field |
31 | * buf: the buffer to write the field value into. |
32 | * len: the length of the buffer |
33 | * @set: write the value of a configuration field |
34 | * vdev: the virtio_device |
35 | * offset: the offset of the configuration field |
36 | * buf: the buffer to read the field value from. |
37 | * len: the length of the buffer |
38 | * @generation: config generation counter (optional) |
39 | * vdev: the virtio_device |
40 | * Returns the config generation counter |
41 | * @get_status: read the status byte |
42 | * vdev: the virtio_device |
43 | * Returns the status byte |
44 | * @set_status: write the status byte |
45 | * vdev: the virtio_device |
46 | * status: the new status byte |
47 | * @reset: reset the device |
48 | * vdev: the virtio device |
49 | * After this, status and feature negotiation must be done again |
50 | * Device must not be reset from its vq/config callbacks, or in |
51 | * parallel with being added/removed. |
52 | * @find_vqs: find virtqueues and instantiate them. |
53 | * vdev: the virtio_device |
54 | * nvqs: the number of virtqueues to find |
55 | * vqs: on success, includes new virtqueues |
56 | * callbacks: array of callbacks, for each virtqueue |
57 | * include a NULL entry for vqs that do not need a callback |
58 | * names: array of virtqueue names (mainly for debugging) |
59 | * include a NULL entry for vqs unused by driver |
60 | * Returns 0 on success or error status |
61 | * @del_vqs: free virtqueues found by find_vqs(). |
62 | * @synchronize_cbs: synchronize with the virtqueue callbacks (optional) |
63 | * The function guarantees that all memory operations on the |
64 | * queue before it are visible to the vring_interrupt() that is |
65 | * called after it. |
66 | * vdev: the virtio_device |
67 | * @get_features: get the array of feature bits for this device. |
68 | * vdev: the virtio_device |
69 | * Returns the first 64 feature bits (all we currently need). |
70 | * @finalize_features: confirm what device features we'll be using. |
71 | * vdev: the virtio_device |
72 | * This sends the driver feature bits to the device: it can change |
73 | * the dev->feature bits if it wants. |
74 | * Note that despite the name this can be called any number of |
75 | * times. |
76 | * Returns 0 on success or error status |
77 | * @bus_name: return the bus name associated with the device (optional) |
78 | * vdev: the virtio_device |
79 | * This returns a pointer to the bus name a la pci_name from which |
80 | * the caller can then copy. |
81 | * @set_vq_affinity: set the affinity for a virtqueue (optional). |
82 | * @get_vq_affinity: get the affinity for a virtqueue (optional). |
83 | * @get_shm_region: get a shared memory region based on the index. |
84 | * @disable_vq_and_reset: reset a queue individually (optional). |
85 | * vq: the virtqueue |
86 | * Returns 0 on success or error status |
87 | * disable_vq_and_reset will guarantee that the callbacks are disabled and |
88 | * synchronized. |
89 | * Except for the callback, the caller should guarantee that the vring is |
90 | * not accessed by any functions of virtqueue. |
91 | * @enable_vq_after_reset: enable a reset queue |
92 | * vq: the virtqueue |
93 | * Returns 0 on success or error status |
94 | * If disable_vq_and_reset is set, then enable_vq_after_reset must also be |
95 | * set. |
96 | * @create_avq: create admin virtqueue resource. |
97 | * @destroy_avq: destroy admin virtqueue resource. |
98 | */ |
99 | struct virtio_config_ops { |
100 | void (*get)(struct virtio_device *vdev, unsigned offset, |
101 | void *buf, unsigned len); |
102 | void (*set)(struct virtio_device *vdev, unsigned offset, |
103 | const void *buf, unsigned len); |
104 | u32 (*generation)(struct virtio_device *vdev); |
105 | u8 (*get_status)(struct virtio_device *vdev); |
106 | void (*set_status)(struct virtio_device *vdev, u8 status); |
107 | void (*reset)(struct virtio_device *vdev); |
108 | int (*find_vqs)(struct virtio_device *, unsigned nvqs, |
109 | struct virtqueue *vqs[], vq_callback_t *callbacks[], |
110 | const char * const names[], const bool *ctx, |
111 | struct irq_affinity *desc); |
112 | void (*del_vqs)(struct virtio_device *); |
113 | void (*synchronize_cbs)(struct virtio_device *); |
114 | u64 (*get_features)(struct virtio_device *vdev); |
115 | int (*finalize_features)(struct virtio_device *vdev); |
116 | const char *(*bus_name)(struct virtio_device *vdev); |
117 | int (*set_vq_affinity)(struct virtqueue *vq, |
118 | const struct cpumask *cpu_mask); |
119 | const struct cpumask *(*get_vq_affinity)(struct virtio_device *vdev, |
120 | int index); |
121 | bool (*get_shm_region)(struct virtio_device *vdev, |
122 | struct virtio_shm_region *region, u8 id); |
123 | int (*disable_vq_and_reset)(struct virtqueue *vq); |
124 | int (*enable_vq_after_reset)(struct virtqueue *vq); |
125 | int (*create_avq)(struct virtio_device *vdev); |
126 | void (*destroy_avq)(struct virtio_device *vdev); |
127 | }; |
128 | |
129 | /* If driver didn't advertise the feature, it will never appear. */ |
130 | void virtio_check_driver_offered_feature(const struct virtio_device *vdev, |
131 | unsigned int fbit); |
132 | |
133 | /** |
134 | * __virtio_test_bit - helper to test feature bits. For use by transports. |
135 | * Devices should normally use virtio_has_feature, |
136 | * which includes more checks. |
137 | * @vdev: the device |
138 | * @fbit: the feature bit |
139 | */ |
140 | static inline bool __virtio_test_bit(const struct virtio_device *vdev, |
141 | unsigned int fbit) |
142 | { |
143 | /* Did you forget to fix assumptions on max features? */ |
144 | if (__builtin_constant_p(fbit)) |
145 | BUILD_BUG_ON(fbit >= 64); |
146 | else |
147 | BUG_ON(fbit >= 64); |
148 | |
149 | return vdev->features & BIT_ULL(fbit); |
150 | } |
151 | |
152 | /** |
153 | * __virtio_set_bit - helper to set feature bits. For use by transports. |
154 | * @vdev: the device |
155 | * @fbit: the feature bit |
156 | */ |
157 | static inline void __virtio_set_bit(struct virtio_device *vdev, |
158 | unsigned int fbit) |
159 | { |
160 | /* Did you forget to fix assumptions on max features? */ |
161 | if (__builtin_constant_p(fbit)) |
162 | BUILD_BUG_ON(fbit >= 64); |
163 | else |
164 | BUG_ON(fbit >= 64); |
165 | |
166 | vdev->features |= BIT_ULL(fbit); |
167 | } |
168 | |
169 | /** |
170 | * __virtio_clear_bit - helper to clear feature bits. For use by transports. |
171 | * @vdev: the device |
172 | * @fbit: the feature bit |
173 | */ |
174 | static inline void __virtio_clear_bit(struct virtio_device *vdev, |
175 | unsigned int fbit) |
176 | { |
177 | /* Did you forget to fix assumptions on max features? */ |
178 | if (__builtin_constant_p(fbit)) |
179 | BUILD_BUG_ON(fbit >= 64); |
180 | else |
181 | BUG_ON(fbit >= 64); |
182 | |
183 | vdev->features &= ~BIT_ULL(fbit); |
184 | } |
185 | |
186 | /** |
187 | * virtio_has_feature - helper to determine if this device has this feature. |
188 | * @vdev: the device |
189 | * @fbit: the feature bit |
190 | */ |
191 | static inline bool virtio_has_feature(const struct virtio_device *vdev, |
192 | unsigned int fbit) |
193 | { |
194 | if (fbit < VIRTIO_TRANSPORT_F_START) |
195 | virtio_check_driver_offered_feature(vdev, fbit); |
196 | |
197 | return __virtio_test_bit(vdev, fbit); |
198 | } |
199 | |
200 | /** |
201 | * virtio_has_dma_quirk - determine whether this device has the DMA quirk |
202 | * @vdev: the device |
203 | */ |
204 | static inline bool virtio_has_dma_quirk(const struct virtio_device *vdev) |
205 | { |
206 | /* |
207 | * Note the reverse polarity of the quirk feature (compared to most |
208 | * other features), this is for compatibility with legacy systems. |
209 | */ |
210 | return !virtio_has_feature(vdev, VIRTIO_F_ACCESS_PLATFORM); |
211 | } |
212 | |
213 | static inline |
214 | struct virtqueue *virtio_find_single_vq(struct virtio_device *vdev, |
215 | vq_callback_t *c, const char *n) |
216 | { |
217 | vq_callback_t *callbacks[] = { c }; |
218 | const char *names[] = { n }; |
219 | struct virtqueue *vq; |
220 | int err = vdev->config->find_vqs(vdev, 1, &vq, callbacks, names, NULL, |
221 | NULL); |
222 | if (err < 0) |
223 | return ERR_PTR(error: err); |
224 | return vq; |
225 | } |
226 | |
227 | static inline |
228 | int virtio_find_vqs(struct virtio_device *vdev, unsigned nvqs, |
229 | struct virtqueue *vqs[], vq_callback_t *callbacks[], |
230 | const char * const names[], |
231 | struct irq_affinity *desc) |
232 | { |
233 | return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, NULL, desc); |
234 | } |
235 | |
236 | static inline |
237 | int virtio_find_vqs_ctx(struct virtio_device *vdev, unsigned nvqs, |
238 | struct virtqueue *vqs[], vq_callback_t *callbacks[], |
239 | const char * const names[], const bool *ctx, |
240 | struct irq_affinity *desc) |
241 | { |
242 | return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, ctx, |
243 | desc); |
244 | } |
245 | |
246 | /** |
247 | * virtio_synchronize_cbs - synchronize with virtqueue callbacks |
248 | * @dev: the virtio device |
249 | */ |
250 | static inline |
251 | void virtio_synchronize_cbs(struct virtio_device *dev) |
252 | { |
253 | if (dev->config->synchronize_cbs) { |
254 | dev->config->synchronize_cbs(dev); |
255 | } else { |
256 | /* |
257 | * A best effort fallback to synchronize with |
258 | * interrupts, preemption and softirq disabled |
259 | * regions. See comment above synchronize_rcu(). |
260 | */ |
261 | synchronize_rcu(); |
262 | } |
263 | } |
264 | |
265 | /** |
266 | * virtio_device_ready - enable vq use in probe function |
267 | * @dev: the virtio device |
268 | * |
269 | * Driver must call this to use vqs in the probe function. |
270 | * |
271 | * Note: vqs are enabled automatically after probe returns. |
272 | */ |
273 | static inline |
274 | void virtio_device_ready(struct virtio_device *dev) |
275 | { |
276 | unsigned status = dev->config->get_status(dev); |
277 | |
278 | WARN_ON(status & VIRTIO_CONFIG_S_DRIVER_OK); |
279 | |
280 | #ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION |
281 | /* |
282 | * The virtio_synchronize_cbs() makes sure vring_interrupt() |
283 | * will see the driver specific setup if it sees vq->broken |
284 | * as false (even if the notifications come before DRIVER_OK). |
285 | */ |
286 | virtio_synchronize_cbs(dev); |
287 | __virtio_unbreak_device(dev); |
288 | #endif |
289 | /* |
290 | * The transport should ensure the visibility of vq->broken |
291 | * before setting DRIVER_OK. See the comments for the transport |
292 | * specific set_status() method. |
293 | * |
294 | * A well behaved device will only notify a virtqueue after |
295 | * DRIVER_OK, this means the device should "see" the coherenct |
296 | * memory write that set vq->broken as false which is done by |
297 | * the driver when it sees DRIVER_OK, then the following |
298 | * driver's vring_interrupt() will see vq->broken as false so |
299 | * we won't lose any notification. |
300 | */ |
301 | dev->config->set_status(dev, status | VIRTIO_CONFIG_S_DRIVER_OK); |
302 | } |
303 | |
304 | static inline |
305 | const char *virtio_bus_name(struct virtio_device *vdev) |
306 | { |
307 | if (!vdev->config->bus_name) |
308 | return "virtio" ; |
309 | return vdev->config->bus_name(vdev); |
310 | } |
311 | |
312 | /** |
313 | * virtqueue_set_affinity - setting affinity for a virtqueue |
314 | * @vq: the virtqueue |
315 | * @cpu_mask: the cpu mask |
316 | * |
317 | * Pay attention the function are best-effort: the affinity hint may not be set |
318 | * due to config support, irq type and sharing. |
319 | * |
320 | */ |
321 | static inline |
322 | int virtqueue_set_affinity(struct virtqueue *vq, const struct cpumask *cpu_mask) |
323 | { |
324 | struct virtio_device *vdev = vq->vdev; |
325 | if (vdev->config->set_vq_affinity) |
326 | return vdev->config->set_vq_affinity(vq, cpu_mask); |
327 | return 0; |
328 | } |
329 | |
330 | static inline |
331 | bool virtio_get_shm_region(struct virtio_device *vdev, |
332 | struct virtio_shm_region *region, u8 id) |
333 | { |
334 | if (!vdev->config->get_shm_region) |
335 | return false; |
336 | return vdev->config->get_shm_region(vdev, region, id); |
337 | } |
338 | |
339 | static inline bool virtio_is_little_endian(struct virtio_device *vdev) |
340 | { |
341 | return virtio_has_feature(vdev, VIRTIO_F_VERSION_1) || |
342 | virtio_legacy_is_little_endian(); |
343 | } |
344 | |
345 | /* Memory accessors */ |
346 | static inline u16 virtio16_to_cpu(struct virtio_device *vdev, __virtio16 val) |
347 | { |
348 | return __virtio16_to_cpu(little_endian: virtio_is_little_endian(vdev), val); |
349 | } |
350 | |
351 | static inline __virtio16 cpu_to_virtio16(struct virtio_device *vdev, u16 val) |
352 | { |
353 | return __cpu_to_virtio16(little_endian: virtio_is_little_endian(vdev), val); |
354 | } |
355 | |
356 | static inline u32 virtio32_to_cpu(struct virtio_device *vdev, __virtio32 val) |
357 | { |
358 | return __virtio32_to_cpu(little_endian: virtio_is_little_endian(vdev), val); |
359 | } |
360 | |
361 | static inline __virtio32 cpu_to_virtio32(struct virtio_device *vdev, u32 val) |
362 | { |
363 | return __cpu_to_virtio32(little_endian: virtio_is_little_endian(vdev), val); |
364 | } |
365 | |
366 | static inline u64 virtio64_to_cpu(struct virtio_device *vdev, __virtio64 val) |
367 | { |
368 | return __virtio64_to_cpu(little_endian: virtio_is_little_endian(vdev), val); |
369 | } |
370 | |
371 | static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val) |
372 | { |
373 | return __cpu_to_virtio64(little_endian: virtio_is_little_endian(vdev), val); |
374 | } |
375 | |
376 | #define virtio_to_cpu(vdev, x) \ |
377 | _Generic((x), \ |
378 | __u8: (x), \ |
379 | __virtio16: virtio16_to_cpu((vdev), (x)), \ |
380 | __virtio32: virtio32_to_cpu((vdev), (x)), \ |
381 | __virtio64: virtio64_to_cpu((vdev), (x)) \ |
382 | ) |
383 | |
384 | #define cpu_to_virtio(vdev, x, m) \ |
385 | _Generic((m), \ |
386 | __u8: (x), \ |
387 | __virtio16: cpu_to_virtio16((vdev), (x)), \ |
388 | __virtio32: cpu_to_virtio32((vdev), (x)), \ |
389 | __virtio64: cpu_to_virtio64((vdev), (x)) \ |
390 | ) |
391 | |
392 | #define __virtio_native_type(structname, member) \ |
393 | typeof(virtio_to_cpu(NULL, ((structname*)0)->member)) |
394 | |
395 | /* Config space accessors. */ |
396 | #define virtio_cread(vdev, structname, member, ptr) \ |
397 | do { \ |
398 | typeof(((structname*)0)->member) virtio_cread_v; \ |
399 | \ |
400 | might_sleep(); \ |
401 | /* Sanity check: must match the member's type */ \ |
402 | typecheck(typeof(virtio_to_cpu((vdev), virtio_cread_v)), *(ptr)); \ |
403 | \ |
404 | switch (sizeof(virtio_cread_v)) { \ |
405 | case 1: \ |
406 | case 2: \ |
407 | case 4: \ |
408 | vdev->config->get((vdev), \ |
409 | offsetof(structname, member), \ |
410 | &virtio_cread_v, \ |
411 | sizeof(virtio_cread_v)); \ |
412 | break; \ |
413 | default: \ |
414 | __virtio_cread_many((vdev), \ |
415 | offsetof(structname, member), \ |
416 | &virtio_cread_v, \ |
417 | 1, \ |
418 | sizeof(virtio_cread_v)); \ |
419 | break; \ |
420 | } \ |
421 | *(ptr) = virtio_to_cpu(vdev, virtio_cread_v); \ |
422 | } while(0) |
423 | |
424 | /* Config space accessors. */ |
425 | #define virtio_cwrite(vdev, structname, member, ptr) \ |
426 | do { \ |
427 | typeof(((structname*)0)->member) virtio_cwrite_v = \ |
428 | cpu_to_virtio(vdev, *(ptr), ((structname*)0)->member); \ |
429 | \ |
430 | might_sleep(); \ |
431 | /* Sanity check: must match the member's type */ \ |
432 | typecheck(typeof(virtio_to_cpu((vdev), virtio_cwrite_v)), *(ptr)); \ |
433 | \ |
434 | vdev->config->set((vdev), offsetof(structname, member), \ |
435 | &virtio_cwrite_v, \ |
436 | sizeof(virtio_cwrite_v)); \ |
437 | } while(0) |
438 | |
439 | /* |
440 | * Nothing virtio-specific about these, but let's worry about generalizing |
441 | * these later. |
442 | */ |
443 | #define virtio_le_to_cpu(x) \ |
444 | _Generic((x), \ |
445 | __u8: (u8)(x), \ |
446 | __le16: (u16)le16_to_cpu(x), \ |
447 | __le32: (u32)le32_to_cpu(x), \ |
448 | __le64: (u64)le64_to_cpu(x) \ |
449 | ) |
450 | |
451 | #define virtio_cpu_to_le(x, m) \ |
452 | _Generic((m), \ |
453 | __u8: (x), \ |
454 | __le16: cpu_to_le16(x), \ |
455 | __le32: cpu_to_le32(x), \ |
456 | __le64: cpu_to_le64(x) \ |
457 | ) |
458 | |
459 | /* LE (e.g. modern) Config space accessors. */ |
460 | #define virtio_cread_le(vdev, structname, member, ptr) \ |
461 | do { \ |
462 | typeof(((structname*)0)->member) virtio_cread_v; \ |
463 | \ |
464 | might_sleep(); \ |
465 | /* Sanity check: must match the member's type */ \ |
466 | typecheck(typeof(virtio_le_to_cpu(virtio_cread_v)), *(ptr)); \ |
467 | \ |
468 | switch (sizeof(virtio_cread_v)) { \ |
469 | case 1: \ |
470 | case 2: \ |
471 | case 4: \ |
472 | vdev->config->get((vdev), \ |
473 | offsetof(structname, member), \ |
474 | &virtio_cread_v, \ |
475 | sizeof(virtio_cread_v)); \ |
476 | break; \ |
477 | default: \ |
478 | __virtio_cread_many((vdev), \ |
479 | offsetof(structname, member), \ |
480 | &virtio_cread_v, \ |
481 | 1, \ |
482 | sizeof(virtio_cread_v)); \ |
483 | break; \ |
484 | } \ |
485 | *(ptr) = virtio_le_to_cpu(virtio_cread_v); \ |
486 | } while(0) |
487 | |
488 | #define virtio_cwrite_le(vdev, structname, member, ptr) \ |
489 | do { \ |
490 | typeof(((structname*)0)->member) virtio_cwrite_v = \ |
491 | virtio_cpu_to_le(*(ptr), ((structname*)0)->member); \ |
492 | \ |
493 | might_sleep(); \ |
494 | /* Sanity check: must match the member's type */ \ |
495 | typecheck(typeof(virtio_le_to_cpu(virtio_cwrite_v)), *(ptr)); \ |
496 | \ |
497 | vdev->config->set((vdev), offsetof(structname, member), \ |
498 | &virtio_cwrite_v, \ |
499 | sizeof(virtio_cwrite_v)); \ |
500 | } while(0) |
501 | |
502 | |
503 | /* Read @count fields, @bytes each. */ |
504 | static inline void __virtio_cread_many(struct virtio_device *vdev, |
505 | unsigned int offset, |
506 | void *buf, size_t count, size_t bytes) |
507 | { |
508 | u32 old, gen = vdev->config->generation ? |
509 | vdev->config->generation(vdev) : 0; |
510 | int i; |
511 | |
512 | might_sleep(); |
513 | do { |
514 | old = gen; |
515 | |
516 | for (i = 0; i < count; i++) |
517 | vdev->config->get(vdev, offset + bytes * i, |
518 | buf + i * bytes, bytes); |
519 | |
520 | gen = vdev->config->generation ? |
521 | vdev->config->generation(vdev) : 0; |
522 | } while (gen != old); |
523 | } |
524 | |
525 | static inline void virtio_cread_bytes(struct virtio_device *vdev, |
526 | unsigned int offset, |
527 | void *buf, size_t len) |
528 | { |
529 | __virtio_cread_many(vdev, offset, buf, count: len, bytes: 1); |
530 | } |
531 | |
532 | static inline u8 virtio_cread8(struct virtio_device *vdev, unsigned int offset) |
533 | { |
534 | u8 ret; |
535 | |
536 | might_sleep(); |
537 | vdev->config->get(vdev, offset, &ret, sizeof(ret)); |
538 | return ret; |
539 | } |
540 | |
541 | static inline void virtio_cwrite8(struct virtio_device *vdev, |
542 | unsigned int offset, u8 val) |
543 | { |
544 | might_sleep(); |
545 | vdev->config->set(vdev, offset, &val, sizeof(val)); |
546 | } |
547 | |
548 | static inline u16 virtio_cread16(struct virtio_device *vdev, |
549 | unsigned int offset) |
550 | { |
551 | __virtio16 ret; |
552 | |
553 | might_sleep(); |
554 | vdev->config->get(vdev, offset, &ret, sizeof(ret)); |
555 | return virtio16_to_cpu(vdev, val: ret); |
556 | } |
557 | |
558 | static inline void virtio_cwrite16(struct virtio_device *vdev, |
559 | unsigned int offset, u16 val) |
560 | { |
561 | __virtio16 v; |
562 | |
563 | might_sleep(); |
564 | v = cpu_to_virtio16(vdev, val); |
565 | vdev->config->set(vdev, offset, &v, sizeof(v)); |
566 | } |
567 | |
568 | static inline u32 virtio_cread32(struct virtio_device *vdev, |
569 | unsigned int offset) |
570 | { |
571 | __virtio32 ret; |
572 | |
573 | might_sleep(); |
574 | vdev->config->get(vdev, offset, &ret, sizeof(ret)); |
575 | return virtio32_to_cpu(vdev, val: ret); |
576 | } |
577 | |
578 | static inline void virtio_cwrite32(struct virtio_device *vdev, |
579 | unsigned int offset, u32 val) |
580 | { |
581 | __virtio32 v; |
582 | |
583 | might_sleep(); |
584 | v = cpu_to_virtio32(vdev, val); |
585 | vdev->config->set(vdev, offset, &v, sizeof(v)); |
586 | } |
587 | |
588 | static inline u64 virtio_cread64(struct virtio_device *vdev, |
589 | unsigned int offset) |
590 | { |
591 | __virtio64 ret; |
592 | |
593 | __virtio_cread_many(vdev, offset, buf: &ret, count: 1, bytes: sizeof(ret)); |
594 | return virtio64_to_cpu(vdev, val: ret); |
595 | } |
596 | |
597 | static inline void virtio_cwrite64(struct virtio_device *vdev, |
598 | unsigned int offset, u64 val) |
599 | { |
600 | __virtio64 v; |
601 | |
602 | might_sleep(); |
603 | v = cpu_to_virtio64(vdev, val); |
604 | vdev->config->set(vdev, offset, &v, sizeof(v)); |
605 | } |
606 | |
607 | /* Conditional config space accessors. */ |
608 | #define virtio_cread_feature(vdev, fbit, structname, member, ptr) \ |
609 | ({ \ |
610 | int _r = 0; \ |
611 | if (!virtio_has_feature(vdev, fbit)) \ |
612 | _r = -ENOENT; \ |
613 | else \ |
614 | virtio_cread((vdev), structname, member, ptr); \ |
615 | _r; \ |
616 | }) |
617 | |
618 | /* Conditional config space accessors. */ |
619 | #define virtio_cread_le_feature(vdev, fbit, structname, member, ptr) \ |
620 | ({ \ |
621 | int _r = 0; \ |
622 | if (!virtio_has_feature(vdev, fbit)) \ |
623 | _r = -ENOENT; \ |
624 | else \ |
625 | virtio_cread_le((vdev), structname, member, ptr); \ |
626 | _r; \ |
627 | }) |
628 | |
629 | #endif /* _LINUX_VIRTIO_CONFIG_H */ |
630 | |