check in the original version of dde linux26.

1 files changed, 130 insertions, 0 deletions

diff --git a/libdde_linux26/contrib/include/linux/virtio_config.h b/libdde_linux26/contrib/include/linux/virtio_config.h
new file mode 100644
index 00000000..bf8ec283
--- /dev/null
+++ b/libdde_linux26/contrib/include/linux/virtio_config.h
@@ -0,0 +1,130 @@
+#ifndef _LINUX_VIRTIO_CONFIG_H
+#define _LINUX_VIRTIO_CONFIG_H
+/* This header, excluding the #ifdef __KERNEL__ part, is BSD licensed so
+ * anyone can use the definitions to implement compatible drivers/servers. */
+
+/* Virtio devices use a standardized configuration space to define their
+ * features and pass configuration information, but each implementation can
+ * store and access that space differently. */
+#include <linux/types.h>
+
+/* Status byte for guest to report progress, and synchronize features. */
+/* We have seen device and processed generic fields (VIRTIO_CONFIG_F_VIRTIO) */
+#define VIRTIO_CONFIG_S_ACKNOWLEDGE	1
+/* We have found a driver for the device. */
+#define VIRTIO_CONFIG_S_DRIVER		2
+/* Driver has used its parts of the config, and is happy */
+#define VIRTIO_CONFIG_S_DRIVER_OK	4
+/* We've given up on this device. */
+#define VIRTIO_CONFIG_S_FAILED		0x80
+
+/* Some virtio feature bits (currently bits 28 through 31) are reserved for the
+ * transport being used (eg. virtio_ring), the rest are per-device feature
+ * bits. */
+#define VIRTIO_TRANSPORT_F_START	28
+#define VIRTIO_TRANSPORT_F_END		32
+
+/* Do we get callbacks when the ring is completely used, even if we've
+ * suppressed them? */
+#define VIRTIO_F_NOTIFY_ON_EMPTY	24
+
+#ifdef __KERNEL__
+#include <linux/virtio.h>
+
+/**
+ * virtio_config_ops - operations for configuring a virtio device
+ * @get: read the value of a configuration field
+ *	vdev: the virtio_device
+ *	offset: the offset of the configuration field
+ *	buf: the buffer to write the field value into.
+ *	len: the length of the buffer
+ * @set: write the value of a configuration field
+ *	vdev: the virtio_device
+ *	offset: the offset of the configuration field
+ *	buf: the buffer to read the field value from.
+ *	len: the length of the buffer
+ * @get_status: read the status byte
+ *	vdev: the virtio_device
+ *	Returns the status byte
+ * @set_status: write the status byte
+ *	vdev: the virtio_device
+ *	status: the new status byte
+ * @reset: reset the device
+ *	vdev: the virtio device
+ *	After this, status and feature negotiation must be done again
+ * @find_vq: find a virtqueue and instantiate it.
+ *	vdev: the virtio_device
+ *	index: the 0-based virtqueue number in case there's more than one.
+ *	callback: the virqtueue callback
+ *	Returns the new virtqueue or ERR_PTR() (eg. -ENOENT).
+ * @del_vq: free a virtqueue found by find_vq().
+ * @get_features: get the array of feature bits for this device.
+ *	vdev: the virtio_device
+ *	Returns the first 32 feature bits (all we currently need).
+ * @finalize_features: confirm what device features we'll be using.
+ *	vdev: the virtio_device
+ *	This gives the final feature bits for the device: it can change
+ *	the dev->feature bits if it wants.
+ */
+struct virtio_config_ops
+{
+	void (*get)(struct virtio_device *vdev, unsigned offset,
+		    void *buf, unsigned len);
+	void (*set)(struct virtio_device *vdev, unsigned offset,
+		    const void *buf, unsigned len);
+	u8 (*get_status)(struct virtio_device *vdev);
+	void (*set_status)(struct virtio_device *vdev, u8 status);
+	void (*reset)(struct virtio_device *vdev);
+	struct virtqueue *(*find_vq)(struct virtio_device *vdev,
+				     unsigned index,
+				     void (*callback)(struct virtqueue *));
+	void (*del_vq)(struct virtqueue *vq);
+	u32 (*get_features)(struct virtio_device *vdev);
+	void (*finalize_features)(struct virtio_device *vdev);
+};
+
+/* If driver didn't advertise the feature, it will never appear. */
+void virtio_check_driver_offered_feature(const struct virtio_device *vdev,
+					 unsigned int fbit);
+
+/**
+ * virtio_has_feature - helper to determine if this device has this feature.
+ * @vdev: the device
+ * @fbit: the feature bit
+ */
+static inline bool virtio_has_feature(const struct virtio_device *vdev,
+				      unsigned int fbit)
+{
+	/* Did you forget to fix assumptions on max features? */
+	if (__builtin_constant_p(fbit))
+		BUILD_BUG_ON(fbit >= 32);
+
+	virtio_check_driver_offered_feature(vdev, fbit);
+	return test_bit(fbit, vdev->features);
+}
+
+/**
+ * virtio_config_val - look for a feature and get a virtio config entry.
+ * @vdev: the virtio device
+ * @fbit: the feature bit
+ * @offset: the type to search for.
+ * @val: a pointer to the value to fill in.
+ *
+ * The return value is -ENOENT if the feature doesn't exist.  Otherwise
+ * the config value is copied into whatever is pointed to by v. */
+#define virtio_config_val(vdev, fbit, offset, v) \
+	virtio_config_buf((vdev), (fbit), (offset), (v), sizeof(*v))
+
+static inline int virtio_config_buf(struct virtio_device *vdev,
+				    unsigned int fbit,
+				    unsigned int offset,
+				    void *buf, unsigned len)
+{
+	if (!virtio_has_feature(vdev, fbit))
+		return -ENOENT;
+
+	vdev->config->get(vdev, offset, buf, len);
+	return 0;
+}
+#endif /* __KERNEL__ */
+#endif /* _LINUX_VIRTIO_CONFIG_H */