Commit 0b90d062 authored by Rusty Russell's avatar Rusty Russell

virtio_config: introduce size-based accessors.

This lets the us do endian conversion if necessary, and insulates the
drivers from that change.
Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
parent bb478d8b
......@@ -162,5 +162,139 @@ int virtqueue_set_affinity(struct virtqueue *vq, int cpu)
return 0;
}
/* Config space accessors. */
#define virtio_cread(vdev, structname, member, ptr) \
do { \
/* Must match the member's type, and be integer */ \
if (!typecheck(typeof((((structname*)0)->member)), *(ptr))) \
(*ptr) = 1; \
\
switch (sizeof(*ptr)) { \
case 1: \
*(ptr) = virtio_cread8(vdev, \
offsetof(structname, member)); \
break; \
case 2: \
*(ptr) = virtio_cread16(vdev, \
offsetof(structname, member)); \
break; \
case 4: \
*(ptr) = virtio_cread32(vdev, \
offsetof(structname, member)); \
break; \
case 8: \
*(ptr) = virtio_cread64(vdev, \
offsetof(structname, member)); \
break; \
default: \
BUG(); \
} \
} while(0)
/* Config space accessors. */
#define virtio_cwrite(vdev, structname, member, ptr) \
do { \
/* Must match the member's type, and be integer */ \
if (!typecheck(typeof((((structname*)0)->member)), *(ptr))) \
BUG_ON((*ptr) == 1); \
\
switch (sizeof(*ptr)) { \
case 1: \
virtio_cwrite8(vdev, \
offsetof(structname, member), \
*(ptr)); \
break; \
case 2: \
virtio_cwrite16(vdev, \
offsetof(structname, member), \
*(ptr)); \
break; \
case 4: \
virtio_cwrite32(vdev, \
offsetof(structname, member), \
*(ptr)); \
break; \
case 8: \
virtio_cwrite64(vdev, \
offsetof(structname, member), \
*(ptr)); \
break; \
default: \
BUG(); \
} \
} while(0)
static inline u8 virtio_cread8(struct virtio_device *vdev, unsigned int offset)
{
u8 ret;
vdev->config->get(vdev, offset, &ret, sizeof(ret));
return ret;
}
static inline void virtio_cread_bytes(struct virtio_device *vdev,
unsigned int offset,
void *buf, size_t len)
{
vdev->config->get(vdev, offset, buf, len);
}
static inline void virtio_cwrite8(struct virtio_device *vdev,
unsigned int offset, u8 val)
{
vdev->config->set(vdev, offset, &val, sizeof(val));
}
static inline u16 virtio_cread16(struct virtio_device *vdev,
unsigned int offset)
{
u16 ret;
vdev->config->get(vdev, offset, &ret, sizeof(ret));
return ret;
}
static inline void virtio_cwrite16(struct virtio_device *vdev,
unsigned int offset, u16 val)
{
vdev->config->set(vdev, offset, &val, sizeof(val));
}
static inline u32 virtio_cread32(struct virtio_device *vdev,
unsigned int offset)
{
u32 ret;
vdev->config->get(vdev, offset, &ret, sizeof(ret));
return ret;
}
static inline void virtio_cwrite32(struct virtio_device *vdev,
unsigned int offset, u32 val)
{
vdev->config->set(vdev, offset, &val, sizeof(val));
}
static inline u64 virtio_cread64(struct virtio_device *vdev,
unsigned int offset)
{
u64 ret;
vdev->config->get(vdev, offset, &ret, sizeof(ret));
return ret;
}
static inline void virtio_cwrite64(struct virtio_device *vdev,
unsigned int offset, u64 val)
{
vdev->config->set(vdev, offset, &val, sizeof(val));
}
/* Conditional config space accessors. */
#define virtio_cread_feature(vdev, fbit, structname, member, ptr) \
({ \
int _r = 0; \
if (!virtio_has_feature(vdev, fbit)) \
_r = -ENOENT; \
else \
virtio_cread((vdev), structname, member, ptr); \
_r; \
})
#endif /* _LINUX_VIRTIO_CONFIG_H */
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