Staging: hv: add the Hyper-V virtual bus

This is the virtual bus that all of the Linux Hyper-V drivers use.

Signed-off-by: Hank Janssen <hjanssen@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 123 insertions, 0 deletions

diff --git a/drivers/staging/hv/RingBuffer.h b/drivers/staging/hv/RingBuffer.h
new file mode 100644
index 0000000..9af5df0
--- /dev/null
+++ b/drivers/staging/hv/RingBuffer.h
@@ -0,0 +1,123 @@
+/*
+ *
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ *
+ */
+
+
+#ifndef _RING_BUFFER_H_
+#define _RING_BUFFER_H_
+
+#include "osd.h"
+
+typedef struct _SG_BUFFER_LIST {
+	PVOID	Data;
+	UINT32	Length;
+} SG_BUFFER_LIST;
+
+typedef struct _RING_BUFFER {
+    volatile UINT32	WriteIndex;     // Offset in bytes from the start of ring data below
+    volatile UINT32	ReadIndex;      // Offset in bytes from the start of ring data below
+
+	volatile UINT32 InterruptMask;
+	UINT8	Reserved[4084];			// Pad it to PAGE_SIZE so that data starts on page boundary
+	// NOTE: The InterruptMask field is used only for channels but since our vmbus connection
+	// also uses this data structure and its data starts here, we commented out this field.
+	// volatile UINT32 InterruptMask;
+	// Ring data starts here + RingDataStartOffset !!! DO NOT place any fields below this !!!
+    UINT8		Buffer[0];
+} STRUCT_PACKED RING_BUFFER;
+
+typedef struct _RING_BUFFER_INFO {
+    RING_BUFFER*	RingBuffer;
+    UINT32			RingSize;			// Include the shared header
+	HANDLE			RingLock;
+
+    UINT32			RingDataSize;		// < ringSize
+	UINT32			RingDataStartOffset;
+
+} RING_BUFFER_INFO;
+
+
+typedef struct _RING_BUFFER_DEBUG_INFO {
+	UINT32		CurrentInterruptMask;
+	UINT32		CurrentReadIndex;
+	UINT32		CurrentWriteIndex;
+	UINT32		BytesAvailToRead;
+	UINT32		BytesAvailToWrite;
+}RING_BUFFER_DEBUG_INFO;
+
+
+//
+// Interface
+//
+
+INTERNAL int
+RingBufferInit(
+	RING_BUFFER_INFO	*RingInfo,
+	PVOID				Buffer,
+	UINT32				BufferLen
+	);
+
+INTERNAL void
+RingBufferCleanup(
+	RING_BUFFER_INFO	*RingInfo
+	);
+
+INTERNAL int
+RingBufferWrite(
+	RING_BUFFER_INFO	*RingInfo,
+	SG_BUFFER_LIST		SgBuffers[],
+	UINT32				SgBufferCount
+	);
+
+INTERNAL int
+RingBufferPeek(
+	RING_BUFFER_INFO	*RingInfo,
+	PVOID				Buffer,
+	UINT32				BufferLen
+	);
+
+INTERNAL int
+RingBufferRead(
+	RING_BUFFER_INFO	*RingInfo,
+	PVOID				Buffer,
+	UINT32				BufferLen,
+	UINT32				Offset
+	);
+
+INTERNAL UINT32
+GetRingBufferInterruptMask(
+	RING_BUFFER_INFO *RingInfo
+	);
+
+INTERNAL void
+DumpRingInfo(
+	RING_BUFFER_INFO* RingInfo,
+	char *Prefix
+	);
+
+INTERNAL void
+RingBufferGetDebugInfo(
+	RING_BUFFER_INFO		*RingInfo,
+	RING_BUFFER_DEBUG_INFO	*DebugInfo
+	);
+
+#endif // _RING_BUFFER_H_