qcacmn: Add stream file system support

Stream file system is wrapper for Relayfs - a Linux specific feature,
which provides efficient method to indicate data to user space. It
depends on qdf debugfs APIs. This feature is protected with
compilation flags WLAN_STREAMFS and WLAN_DEBUGFS.

Change-Id: I1401112ece290e6d0560623cf10faaf498ebb1b7
CRs-Fixed: 2635481

qdf/inc/qdf_streamfs.h

@@ -0,0 +1,207 @@
+/*
+ * Copyright (c) 2018, 2020 The Linux Foundation. All rights reserved.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for
+ * any purpose with or without fee is hereby granted, provided that the
+ * above copyright notice and this permission notice appear in all
+ * copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
+ * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
+ * AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
+ * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
+ * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/**
+ * DOC: qdf_streamfs.h
+ * This file provides OS abstraction for stream filesystem APIs.
+ */
+
+#ifndef _QDF_STREAMFS_H
+#define _QDF_STREAMFS_H
+
+#include <i_qdf_streamfs.h>
+#include <qdf_types.h>
+#include <qdf_debugfs.h>
+
+typedef __qdf_streamfs_chan_t qdf_streamfs_chan_t;
+typedef __qdf_streamfs_chan_buf_t qdf_streamfs_chan_buf_t;
+
+#ifdef WLAN_STREAMFS
+/**
+ * qdf_streamfs_create_dir() - wrapper to create a debugfs directory
+ * @name: name of the new directory
+ * @parent: parent node. If NULL, defaults to base qdf_debugfs_root
+ *
+ * Return: dentry structure pointer in case of success, otherwise NULL.
+ *
+ */
+static inline qdf_dentry_t qdf_streamfs_create_dir(
+			const char *name, qdf_dentry_t parent)
+{
+	return qdf_debugfs_create_dir(name, parent);
+}
+
+/**
+ * qdf_streamfs_remove_file() - wrapper to remove streamfs file
+ * @d: streamfs node
+ *
+ */
+static inline void qdf_streamfs_remove_file(qdf_dentry_t d)
+{
+	qdf_debugfs_remove_file(d);
+}
+
+/**
+ * qdf_debugfs_remove_dir_recursive() - wrapper to remove directory recursively
+ * @d: debugfs node
+ *
+ * This function will recursively remove a directory in streamfs that was
+ * previously created with a call to qdf_debugfs_create_file() or it's
+ * variant functions.
+ */
+static inline void qdf_streamfs_remove_dir_recursive(qdf_dentry_t d)
+{
+	qdf_debugfs_remove_dir_recursive(d);
+}
+
+/**
+ * qdf_streamfs_create_file() - Create streamfs chan buffer file
+ * @name: base name of file to create
+ * @mode: filemode
+ * @parent: dentry of parent directory, NULL for root directory
+ * @buf: pointer to chan buffer
+ *
+ * Returns file dentry pointer if successful, NULL otherwise.
+ */
+qdf_dentry_t qdf_streamfs_create_file(const char *name, uint16_t mode,
+				      qdf_dentry_t parent,
+				      qdf_streamfs_chan_buf_t buf);
+
+/**
+ * qdf_streamfs_open() - Create streamfs channel for data trasfer
+ * @base_filename: base name of files to create, %NULL for buffering only
+ * @parent: dentry of parent directory, %NULL for root directory
+ * @subbuf_size: size of sub-buffers
+ * @n_subbufs: number of sub-buffers
+ * @private_data: user-defined data
+ *
+ * Returns channel pointer if successful, %NULL otherwise.
+ */
+qdf_streamfs_chan_t qdf_streamfs_open(const char *base_filename,
+				      qdf_dentry_t parent,
+				      size_t subbuf_size, size_t n_subbufs,
+				      void *private_data);
+
+/**
+ * qdf_streamfs_close() - Closes all channel buffers and frees the channel.
+ * @chan: pointer to qdf_streamfs_chan.
+ *
+ * Returns NONE
+ */
+void qdf_streamfs_close(qdf_streamfs_chan_t chan);
+
+/**
+ * qdf_streamfs_flush() - Flushes all channel buffers.
+ * @chan: pointer to qdf_streamfs_chan.
+ *
+ * Returns NONE
+ */
+void qdf_streamfs_flush(qdf_streamfs_chan_t chan);
+
+/**
+ * qdf_streamfs_reset() - Reset streamfs channel
+ * @chan: pointer to qdf_streamfs_chan.
+ *
+ * This erases data from all channel buffers and restarting the channel
+ * in its initial state. The buffers are not freed, so any mappings are
+ * still in effect.
+ *
+ * Returns NONE
+ */
+void qdf_streamfs_reset(qdf_streamfs_chan_t chan);
+
+/**
+ * qdf_streamfs_subbufs_consumed() - update the buffer's sub-buffers-consumed
+ * count
+ * @chan: pointer to qdf_streamfs_chan.
+ * @cpu: the cpu associated with the channel buffer to update
+ * @subbufs_consumed: number of sub-buffers to add to current buf's count
+ *
+ * Returns NONE
+ */
+void qdf_streamfs_subbufs_consumed(qdf_streamfs_chan_t chan,
+				   unsigned int cpu,
+				   size_t consumed);
+
+/**
+ * qdf_streamfs_write() - write data into the channel
+ * @chan: relay channel
+ * @data: data to be written
+ * @length: number of bytes to write
+ *
+ * Writes data into the current cpu's channel buffer.
+ */
+void qdf_streamfs_write(qdf_streamfs_chan_t chan, const void *data,
+			size_t length);
+#else
+static inline qdf_dentry_t qdf_streamfs_create_dir(
+			const char *name, qdf_dentry_t parent)
+{
+	return NULL;
+}
+
+static inline void qdf_streamfs_remove_file(qdf_dentry_t d)
+{
+}
+
+static inline void qdf_streamfs_remove_dir_recursive(qdf_dentry_t d)
+{
+}
+
+static inline
+qdf_dentry_t qdf_streamfs_create_file(const char *name, uint16_t mode,
+				      qdf_dentry_t parent,
+				      qdf_streamfs_chan_buf_t buf)
+{
+	return NULL;
+}
+
+static inline
+qdf_streamfs_chan_t qdf_streamfs_open(const char *base_filename,
+				      qdf_dentry_t parent,
+				      size_t subbuf_size, size_t n_subbufs,
+				      void *private_data)
+{
+	return NULL;
+}
+
+static inline void qdf_streamfs_close(qdf_streamfs_chan_t chan)
+{
+}
+
+static inline void qdf_streamfs_flush(qdf_streamfs_chan_t chan)
+{
+}
+
+static inline void qdf_streamfs_reset(qdf_streamfs_chan_t chan)
+{
+}
+
+static inline void
+qdf_streamfs_subbufs_consumed(qdf_streamfs_chan_t chan,
+			      unsigned int cpu, size_t consumed)
+{
+}
+
+static inline void
+qdf_streamfs_write(qdf_streamfs_chan_t chan, const void *data,
+		   size_t length)
+{
+}
+#endif /* WLAN_STREAMFS */
+#endif /* _QDF_STREAMFS_H */