--- /dev/null
+#ifndef _LINUX_RING_BUFFER_BACKEND_TYPES_H
+#define _LINUX_RING_BUFFER_BACKEND_TYPES_H
+
+/*
+ * linux/ringbuffer/backend_types.h
+ *
+ * Copyright (C) 2008-2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * Ring buffer backend (types).
+ *
+ * Dual LGPL v2.1/GPL v2 license.
+ */
+
+#include <linux/cpumask.h>
+#include <linux/types.h>
+
+struct lib_ring_buffer_backend_page {
+ void *virt; /* page virtual address (cached) */
+ struct page *page; /* pointer to page structure */
+};
+
+struct lib_ring_buffer_backend_pages {
+ unsigned long mmap_offset; /* offset of the subbuffer in mmap */
+ union v_atomic records_commit; /* current records committed count */
+ union v_atomic records_unread; /* records to read */
+ unsigned long data_size; /* Amount of data to read from subbuf */
+ struct lib_ring_buffer_backend_page p[];
+};
+
+struct lib_ring_buffer_backend_subbuffer {
+ /* Identifier for subbuf backend pages. Exchanged atomically. */
+ unsigned long id; /* backend subbuffer identifier */
+};
+
+/*
+ * Forward declaration of frontend-specific channel and ring_buffer.
+ */
+struct channel;
+struct lib_ring_buffer;
+
+struct lib_ring_buffer_backend {
+ /* Array of ring_buffer_backend_subbuffer for writer */
+ struct lib_ring_buffer_backend_subbuffer *buf_wsb;
+ /* ring_buffer_backend_subbuffer for reader */
+ struct lib_ring_buffer_backend_subbuffer buf_rsb;
+ /*
+ * Pointer array of backend pages, for whole buffer.
+ * Indexed by ring_buffer_backend_subbuffer identifier (id) index.
+ */
+ struct lib_ring_buffer_backend_pages **array;
+ unsigned int num_pages_per_subbuf;
+
+ struct channel *chan; /* Associated channel */
+ int cpu; /* This buffer's cpu. -1 if global. */
+ union v_atomic records_read; /* Number of records read */
+ unsigned int allocated:1; /* Bool: is buffer allocated ? */
+};
+
+struct channel_backend {
+ unsigned long buf_size; /* Size of the buffer */
+ unsigned long subbuf_size; /* Sub-buffer size */
+ unsigned int subbuf_size_order; /* Order of sub-buffer size */
+ unsigned int num_subbuf_order; /*
+ * Order of number of sub-buffers/buffer
+ * for writer.
+ */
+ unsigned int buf_size_order; /* Order of buffer size */
+ int extra_reader_sb:1; /* Bool: has extra reader subbuffer */
+ struct lib_ring_buffer *buf; /* Channel per-cpu buffers */
+
+ unsigned long num_subbuf; /* Number of sub-buffers for writer */
+ u64 start_tsc; /* Channel creation TSC value */
+ void *priv; /* Client-specific information */
+ struct notifier_block cpu_hp_notifier; /* CPU hotplug notifier */
+ const struct lib_ring_buffer_config *config; /* Ring buffer configuration */
+ cpumask_var_t cpumask; /* Allocated per-cpu buffers cpumask */
+ char name[NAME_MAX]; /* Channel name */
+};
+
+#endif /* _LINUX_RING_BUFFER_BACKEND_TYPES_H */