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virtio_config: LE config space accessors

To be used by modern code, as well as to handle LE only fields such as balloon.

Michael S. Tsirkin committed 6 years ago

Commit e5989601 parent 14191c11 file · +65 −0Browse files

Unified · Split

include/linux/virtio_config.h+65−0
@@ -375,6 +375,71 @@ static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val) · 374 unmodified lines
375 sizeof(virtio_cwrite_v)); \375 sizeof(virtio_cwrite_v)); \
376 } while(0)376 } while(0)
377 377
378/*
379 * Nothing virtio-specific about these, but let's worry about generalizing
380 * these later.
381 */
382#define virtio_le_to_cpu(x) \
383 _Generic((x), \
384 __u8: (x), \
385 __le16: le16_to_cpu(x), \
386 __le32: le32_to_cpu(x), \
387 __le64: le64_to_cpu(x) \
388 )
389
390#define virtio_cpu_to_le(x, m) \
391 _Generic((m), \
392 __u8: (x), \
393 __le16: cpu_to_le16(x), \
394 __le32: cpu_to_le32(x), \
395 __le64: cpu_to_le64(x) \
396 )
397
398/* LE (e.g. modern) Config space accessors. */
399#define virtio_cread_le(vdev, structname, member, ptr) \
400 do { \
401 typeof(((structname*)0)->member) virtio_cread_v; \
402 \
403 might_sleep(); \
404 /* Sanity check: must match the member's type */ \
405 typecheck(typeof(virtio_le_to_cpu(virtio_cread_v)), *(ptr)); \
406 \
407 switch (sizeof(virtio_cread_v)) { \
408 case 1: \
409 case 2: \
410 case 4: \
411 vdev->config->get((vdev), \
412 offsetof(structname, member), \
413 &virtio_cread_v, \
414 sizeof(virtio_cread_v)); \
415 break; \
416 default: \
417 __virtio_cread_many((vdev), \
418 offsetof(structname, member), \
419 &virtio_cread_v, \
420 1, \
421 sizeof(virtio_cread_v)); \
422 break; \
423 } \
424 *(ptr) = virtio_le_to_cpu(virtio_cread_v); \
425 } while(0)
426
427/* Config space accessors. */
428#define virtio_cwrite_le(vdev, structname, member, ptr) \
429 do { \
430 typeof(((structname*)0)->member) virtio_cwrite_v = \
431 virtio_cpu_to_le(*(ptr), ((structname*)0)->member); \
432 \
433 might_sleep(); \
434 /* Sanity check: must match the member's type */ \
435 typecheck(typeof(virtio_le_to_cpu(virtio_cwrite_v)), *(ptr)); \
436 \
437 vdev->config->set((vdev), offsetof(structname, member), \
438 &virtio_cwrite_v, \
439 sizeof(virtio_cwrite_v)); \
440 } while(0)
441
442
378/* Read @count fields, @bytes each. */443/* Read @count fields, @bytes each. */
379static inline void __virtio_cread_many(struct virtio_device *vdev,444static inline void __virtio_cread_many(struct virtio_device *vdev,
380 unsigned int offset,445 unsigned int offset,