File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/net/mac80211/rc80211_minstrel_debugfs.c b/net/mac80211/rc80211_minstrel_debugfs.c
new file mode 100644
index 0000000..820b0ab
--- /dev/null
+++ b/net/mac80211/rc80211_minstrel_debugfs.c
@@ -0,0 +1,232 @@
+/*
+ * 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 <linux/slab.h>
+#include <linux/export.h>
+#include <net/mac80211.h>
+#include "rc80211_minstrel.h"
+
+ssize_t
+minstrel_stats_read(struct file *file, char __user *buf, size_t len, loff_t *ppos)
+{
+	struct minstrel_debugfs_info *ms;
+
+	ms = file->private_data;
+	return simple_read_from_buffer(buf, len, ppos, ms->buf, ms->len);
+}
+
+int
+minstrel_stats_release(struct inode *inode, struct file *file)
+{
+	kfree(file->private_data);
+	return 0;
+}
+
+int
+minstrel_stats_open(struct inode *inode, struct file *file)
+{
+	struct minstrel_sta_info *mi = inode->i_private;
+	struct minstrel_debugfs_info *ms;
+	unsigned int i, tp_max, tp_avg, prob, eprob;
+	char *p;
+
+	ms = kmalloc(2048, GFP_KERNEL);
+	if (!ms)
+		return -ENOMEM;
+
+	file->private_data = ms;
+	p = ms->buf;
+	p += sprintf(p, "\n");
+	p += sprintf(p,
+		     "best   __________rate_________    ________statistics________    ________last_______    ______sum-of________\n");
+	p += sprintf(p,
+		     "rate  [name idx airtime max_tp]  [avg(tp) avg(prob) sd(prob)]  [prob.|retry|suc|att]  [#success | #attempts]\n");
+
+	for (i = 0; i < mi->n_rates; i++) {
+		struct minstrel_rate *mr = &mi->r[i];
+		struct minstrel_rate_stats *mrs = &mi->r[i].stats;
+
+		*(p++) = (i == mi->max_tp_rate[0]) ? 'A' : ' ';
+		*(p++) = (i == mi->max_tp_rate[1]) ? 'B' : ' ';
+		*(p++) = (i == mi->max_tp_rate[2]) ? 'C' : ' ';
+		*(p++) = (i == mi->max_tp_rate[3]) ? 'D' : ' ';
+		*(p++) = (i == mi->max_prob_rate) ? 'P' : ' ';
+
+		p += sprintf(p, " %3u%s ", mr->bitrate / 2,
+				(mr->bitrate & 1 ? ".5" : "  "));
+		p += sprintf(p, "%3u  ", i);
+		p += sprintf(p, "%6u ", mr->perfect_tx_time);
+
+		tp_max = minstrel_get_tp_avg(mr, MINSTREL_FRAC(100,100));
+		tp_avg = minstrel_get_tp_avg(mr, mrs->prob_ewma);
+		prob = MINSTREL_TRUNC(mrs->cur_prob * 1000);
+		eprob = MINSTREL_TRUNC(mrs->prob_ewma * 1000);
+
+		p += sprintf(p, "%4u.%1u    %4u.%1u     %3u.%1u    %3u.%1u"
+				"     %3u.%1u %3u   %3u %-3u   "
+				"%9llu   %-9llu\n",
+				tp_max / 10, tp_max % 10,
+				tp_avg / 10, tp_avg % 10,
+				eprob / 10, eprob % 10,
+				mrs->prob_ewmsd / 10, mrs->prob_ewmsd % 10,
+				prob / 10, prob % 10,
+				mrs->retry_count,
+				mrs->last_success,
+				mrs->last_attempts,
+				(unsigned long long)mrs->succ_hist,
+				(unsigned long long)mrs->att_hist);
+	}
+	p += sprintf(p, "\nTotal packet count::    ideal %d      "
+			"lookaround %d\n\n",
+			mi->total_packets - mi->sample_packets,
+			mi->sample_packets);
+	ms->len = p - ms->buf;
+
+	WARN_ON(ms->len + sizeof(*ms) > 2048);
+
+	return 0;
+}
+
+static const struct file_operations minstrel_stat_fops = {
+	.owner = THIS_MODULE,
+	.open = minstrel_stats_open,
+	.read = minstrel_stats_read,
+	.release = minstrel_stats_release,
+	.llseek = default_llseek,
+};
+
+int
+minstrel_stats_csv_open(struct inode *inode, struct file *file)
+{
+	struct minstrel_sta_info *mi = inode->i_private;
+	struct minstrel_debugfs_info *ms;
+	unsigned int i, tp_max, tp_avg, prob, eprob;
+	char *p;
+
+	ms = kmalloc(2048, GFP_KERNEL);
+	if (!ms)
+		return -ENOMEM;
+
+	file->private_data = ms;
+	p = ms->buf;
+
+	for (i = 0; i < mi->n_rates; i++) {
+		struct minstrel_rate *mr = &mi->r[i];
+		struct minstrel_rate_stats *mrs = &mi->r[i].stats;
+
+		p += sprintf(p, "%s" ,((i == mi->max_tp_rate[0]) ? "A" : ""));
+		p += sprintf(p, "%s" ,((i == mi->max_tp_rate[1]) ? "B" : ""));
+		p += sprintf(p, "%s" ,((i == mi->max_tp_rate[2]) ? "C" : ""));
+		p += sprintf(p, "%s" ,((i == mi->max_tp_rate[3]) ? "D" : ""));
+		p += sprintf(p, "%s" ,((i == mi->max_prob_rate) ? "P" : ""));
+
+		p += sprintf(p, ",%u%s", mr->bitrate / 2,
+				(mr->bitrate & 1 ? ".5," : ","));
+		p += sprintf(p, "%u,", i);
+		p += sprintf(p, "%u,",mr->perfect_tx_time);
+
+		tp_max = minstrel_get_tp_avg(mr, MINSTREL_FRAC(100,100));
+		tp_avg = minstrel_get_tp_avg(mr, mrs->prob_ewma);
+		prob = MINSTREL_TRUNC(mrs->cur_prob * 1000);
+		eprob = MINSTREL_TRUNC(mrs->prob_ewma * 1000);
+
+		p += sprintf(p, "%u.%u,%u.%u,%u.%u,%u.%u,%u.%u,%u,%u,%u,"
+				"%llu,%llu,%d,%d\n",
+				tp_max / 10, tp_max % 10,
+				tp_avg / 10, tp_avg % 10,
+				eprob / 10, eprob % 10,
+				mrs->prob_ewmsd / 10, mrs->prob_ewmsd % 10,
+				prob / 10, prob % 10,
+				mrs->retry_count,
+				mrs->last_success,
+				mrs->last_attempts,
+				(unsigned long long)mrs->succ_hist,
+				(unsigned long long)mrs->att_hist,
+				mi->total_packets - mi->sample_packets,
+				mi->sample_packets);
+
+	}
+	ms->len = p - ms->buf;
+
+	WARN_ON(ms->len + sizeof(*ms) > 2048);
+
+	return 0;
+}
+
+static const struct file_operations minstrel_stat_csv_fops = {
+	.owner = THIS_MODULE,
+	.open = minstrel_stats_csv_open,
+	.read = minstrel_stats_read,
+	.release = minstrel_stats_release,
+	.llseek = default_llseek,
+};
+
+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);
+
+	mi->dbg_stats_csv = debugfs_create_file("rc_stats_csv", S_IRUGO, dir,
+			mi, &minstrel_stat_csv_fops);
+}
+
+void
+minstrel_remove_sta_debugfs(void *priv, void *priv_sta)
+{
+	struct minstrel_sta_info *mi = priv_sta;
+
+	debugfs_remove(mi->dbg_stats);
+
+	debugfs_remove(mi->dbg_stats_csv);
+}