mac80211: add the 'minstrel' rate control algorithm

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/rc80211_minstrel_debugfs.c b/net/mac80211/rc80211_minstrel_debugfs.c
new file mode 100644
index 0000000..0b024cd
--- /dev/null
+++ b/net/mac80211/rc80211_minstrel_debugfs.c
@@ -0,0 +1,164 @@
+/*
+ * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Based on minstrel.c:
+ *   Copyright (C) 2005-2007 Derek Smithies <derek@indranet.co.nz>
+ *   Sponsored by Indranet Technologies Ltd
+ *
+ * Based on sample.c:
+ *   Copyright (c) 2005 John Bicket
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *   1. Redistributions of source code must retain the above copyright
+ *      notice, this list of conditions and the following disclaimer,
+ *      without modification.
+ *   2. Redistributions in binary form must reproduce at minimum a disclaimer
+ *      similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
+ *      redistribution must be conditioned upon including a substantially
+ *      similar Disclaimer requirement for further binary redistribution.
+ *   3. Neither the names of the above-listed copyright holders nor the names
+ *      of any contributors may be used to endorse or promote products derived
+ *      from this software without specific prior written permission.
+ *
+ *   Alternatively, this software may be distributed under the terms of the
+ *   GNU General Public License ("GPL") version 2 as published by the Free
+ *   Software Foundation.
+ *
+ *   NO WARRANTY
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
+ *   AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+ *   THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
+ *   OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ *   SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ *   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
+ *   IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ *   ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ *   THE POSSIBILITY OF SUCH DAMAGES.
+ */
+#include <linux/netdevice.h>
+#include <linux/types.h>
+#include <linux/skbuff.h>
+#include <linux/debugfs.h>
+#include <linux/ieee80211.h>
+#include <net/mac80211.h>
+#include "rc80211_minstrel.h"
+
+struct minstrel_stats_info {
+	struct minstrel_sta_info *mi;
+	char buf[4096];
+	size_t len;
+};
+
+static int
+minstrel_stats_open(struct inode *inode, struct file *file)
+{
+	struct minstrel_sta_info *mi = inode->i_private;
+	struct minstrel_stats_info *ms;
+	unsigned int i, tp, prob, eprob;
+	char *p;
+
+	ms = kmalloc(sizeof(*ms), GFP_KERNEL);
+	if (!ms)
+		return -ENOMEM;
+
+	file->private_data = ms;
+	p = ms->buf;
+	p += sprintf(p, "rate     throughput  ewma prob   this prob  "
+			"this succ/attempt   success    attempts\n");
+	for (i = 0; i < mi->n_rates; i++) {
+		struct minstrel_rate *mr = &mi->r[i];
+
+		*(p++) = (i == mi->max_tp_rate) ? 'T' : ' ';
+		*(p++) = (i == mi->max_tp_rate2) ? 't' : ' ';
+		*(p++) = (i == mi->max_prob_rate) ? 'P' : ' ';
+		p += sprintf(p, "%3u%s", mr->bitrate / 2,
+				(mr->bitrate & 1 ? ".5" : "  "));
+
+		tp = ((mr->cur_tp * 96) / 18000) >> 10;
+		prob = mr->cur_prob / 18;
+		eprob = mr->probability / 18;
+
+		p += sprintf(p, "  %6u.%1u   %6u.%1u   %6u.%1u        "
+				"%3u(%3u)   %8llu    %8llu\n",
+				tp / 10, tp % 10,
+				eprob / 10, eprob % 10,
+				prob / 10, prob % 10,
+				mr->last_success,
+				mr->last_attempts,
+				mr->succ_hist,
+				mr->att_hist);
+	}
+	p += sprintf(p, "\nTotal packet count::    ideal %d      "
+			"lookaround %d\n\n",
+			mi->packet_count - mi->sample_count,
+			mi->sample_count);
+	ms->len = p - ms->buf;
+
+	return 0;
+}
+
+static int
+minstrel_stats_read(struct file *file, char __user *buf, size_t len, loff_t *o)
+{
+	struct minstrel_stats_info *ms;
+	char *src;
+
+	ms = file->private_data;
+	src = ms->buf;
+
+	len = min(len, ms->len);
+	if (len <= *o)
+		return 0;
+
+	src += *o;
+	len -= *o;
+	*o += len;
+
+	if (copy_to_user(buf, src, len))
+		return -EFAULT;
+
+	return len;
+}
+
+static int
+minstrel_stats_release(struct inode *inode, struct file *file)
+{
+	struct minstrel_stats_info *ms = file->private_data;
+
+	kfree(ms);
+
+	return 0;
+}
+
+static struct file_operations minstrel_stat_fops = {
+	.owner = THIS_MODULE,
+	.open = minstrel_stats_open,
+	.read = minstrel_stats_read,
+	.release = minstrel_stats_release,
+};
+
+void
+minstrel_add_sta_debugfs(void *priv, void *priv_sta, struct dentry *dir)
+{
+	struct minstrel_sta_info *mi = priv_sta;
+
+	mi->dbg_stats = debugfs_create_file("rc_stats", S_IRUGO, dir, mi,
+			&minstrel_stat_fops);
+}
+
+void
+minstrel_remove_sta_debugfs(void *priv, void *priv_sta)
+{
+	struct minstrel_sta_info *mi = priv_sta;
+
+	debugfs_remove(mi->dbg_stats);
+}