diff options
author | Rusty Russell <rusty@rustcorp.com.au> | 2013-10-14 18:11:51 +1030 |
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committer | Rusty Russell <rusty@rustcorp.com.au> | 2013-10-17 10:55:36 +1030 |
commit | 0b90d0622ad290b3717a13489b396af52aea9d2d (patch) | |
tree | b40dcc4d3ac3fb9d7c34381e82523b7e6cd8a0fa | |
parent | bb478d8b167cf875565ac7d927ffbdc0b6d280e8 (diff) | |
download | linux-0b90d0622ad290b3717a13489b396af52aea9d2d.tar.bz2 |
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: Rusty Russell <rusty@rustcorp.com.au>
-rw-r--r-- | include/linux/virtio_config.h | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h index 29b9104232b4..490a4bbd59a3 100644 --- a/include/linux/virtio_config.h +++ b/include/linux/virtio_config.h @@ -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 */ |