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/linux/src/i_qdf_streamfs.h

@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 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: i_qdf_streamfs.h
+ * Linux specific implementation for stream filesystem APIs.
+ */
+
+#ifndef _I_QDF_STREAMFS_H
+#define _I_QDF_STREAMFS_H
+
+#include <linux/relay.h>
+
+typedef struct rchan *__qdf_streamfs_chan_t;
+typedef struct rchan_buf *__qdf_streamfs_chan_buf_t;
+
+#endif /* _I_QDF_STREAMFS_H */

qdf/linux/src/qdf_streamfs.c

@@ -0,0 +1,149 @@
+/*
+ * 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
+ * This file provides QDF stream file system APIs
+ */
+
+#include <i_qdf_streamfs.h>
+#include <qdf_trace.h>
+#include <qdf_streamfs.h>
+#include <qdf_module.h>
+
+/**
+ * qdf_create_buf_file_handler() - Create streamfs buffer file
+ * @filename: base name of files to create, NULL for buffering only
+ * @parent: dentry of parent directory, NULL for root directory
+ * @mode: filemode
+ * @buf: streamfs channel buf
+ * @is_global: pointer to set whether this buf file is global or not.
+ *
+ *  Returns dentry if successful, NULL otherwise.
+ */
+static qdf_dentry_t
+qdf_create_buf_file_handler(const char *filename, qdf_dentry_t parent,
+			    uint16_t mode, qdf_streamfs_chan_buf_t buf,
+			    int32_t *is_global)
+{
+	qdf_dentry_t buf_file;
+	*is_global = 1;
+	buf_file = qdf_streamfs_create_file(filename, mode, parent, buf);
+
+	if (!buf_file)
+		return NULL;
+
+	return buf_file;
+}
+
+/**
+ * qdf_remove_buf_file_handler() - Remove streamfs buffer file
+ *  @dentry:dentry
+ */
+static int qdf_remove_buf_file_handler(qdf_dentry_t dentry)
+{
+	qdf_streamfs_remove_file(dentry);
+
+	return 0;
+}
+
+static struct rchan_callbacks g_qdf_streamfs_cb = {
+	.create_buf_file = qdf_create_buf_file_handler,
+	.remove_buf_file = qdf_remove_buf_file_handler,
+};
+
+qdf_dentry_t
+qdf_streamfs_create_file(const char *name, uint16_t mode,
+			 qdf_dentry_t parent,
+			 qdf_streamfs_chan_buf_t buf)
+{
+	qdf_dentry_t file = NULL;
+
+	if (!name)
+		return NULL;
+
+	file = debugfs_create_file(name, mode,
+				   (struct dentry *)parent,
+				   buf, &relay_file_operations);
+
+	return file;
+}
+
+qdf_export_symbol(qdf_streamfs_create_file);
+
+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_chan_t channel_ptr = NULL;
+
+	channel_ptr = relay_open(base_filename,
+				 (struct dentry *)parent,
+				 subbuf_size, n_subbufs,
+				 &g_qdf_streamfs_cb,
+				 private_data);
+
+	return channel_ptr;
+}
+
+qdf_export_symbol(qdf_streamfs_open);
+
+void qdf_streamfs_close(qdf_streamfs_chan_t chan)
+{
+	if (chan)
+		relay_close(chan);
+}
+
+qdf_export_symbol(qdf_streamfs_close);
+
+void qdf_streamfs_flush(qdf_streamfs_chan_t chan)
+{
+	if (chan)
+		relay_flush(chan);
+}
+
+qdf_export_symbol(qdf_streamfs_flush);
+
+void qdf_streamfs_reset(qdf_streamfs_chan_t chan)
+{
+	if (chan)
+		relay_reset(chan);
+}
+
+qdf_export_symbol(qdf_streamfs_reset);
+
+void qdf_streamfs_subbufs_consumed(qdf_streamfs_chan_t chan,
+				   unsigned int cpu,
+				   size_t consumed)
+{
+	if (chan)
+		relay_subbufs_consumed(chan, cpu, consumed);
+}
+
+qdf_export_symbol(qdf_streamfs_subbufs_consumed);
+
+void qdf_streamfs_write(qdf_streamfs_chan_t chan,
+			const void *data,
+			size_t length)
+{
+	if (chan)
+		relay_write(chan, data, length);
+}
+
+qdf_export_symbol(qdf_streamfs_write);