From: Felix Fietkau <nbd@nbd.name>
Date: Sat, 10 Feb 2018 12:43:30 +0100
Subject: [PATCH] mac80211: minstrel: merge with minstrel_ht, always enable
 VHT support

Legacy-only devices are not very common and the overhead of the extra
code for HT and VHT rates is not big enough to justify all those extra
lines of code to make it optional.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
---

--- a/net/mac80211/Kconfig
+++ b/net/mac80211/Kconfig
@@ -25,20 +25,6 @@ config MAC80211_RC_MINSTREL
 	---help---
 	  This option enables the 'minstrel' TX rate control algorithm
 
-config MAC80211_RC_MINSTREL_HT
-	bool "Minstrel 802.11n support" if EXPERT
-	depends on MAC80211_RC_MINSTREL
-	default y
-	---help---
-	  This option enables the 'minstrel_ht' TX rate control algorithm
-
-config MAC80211_RC_MINSTREL_VHT
-	bool "Minstrel 802.11ac support" if EXPERT
-	depends on MAC80211_RC_MINSTREL_HT
-	default n
-	---help---
-	  This option enables VHT in the 'minstrel_ht' TX rate control algorithm
-
 choice
 	prompt "Default rate control algorithm"
 	depends on MAC80211_HAS_RC
@@ -60,8 +46,7 @@ endchoice
 
 config MAC80211_RC_DEFAULT
 	string
-	default "minstrel_ht" if MAC80211_RC_DEFAULT_MINSTREL && MAC80211_RC_MINSTREL_HT
-	default "minstrel" if MAC80211_RC_DEFAULT_MINSTREL
+	default "minstrel_ht" if MAC80211_RC_DEFAULT_MINSTREL
 	default ""
 
 endif
--- a/net/mac80211/Makefile
+++ b/net/mac80211/Makefile
@@ -52,13 +52,14 @@ mac80211-$(CONFIG_PM) += pm.o
 
 CFLAGS_trace.o := -I$(src)
 
-rc80211_minstrel-y := rc80211_minstrel.o
-rc80211_minstrel-$(CPTCFG_MAC80211_DEBUGFS) += rc80211_minstrel_debugfs.o
+rc80211_minstrel-y := \
+	rc80211_minstrel.o \
+	rc80211_minstrel_ht.o
 
-rc80211_minstrel_ht-y := rc80211_minstrel_ht.o
-rc80211_minstrel_ht-$(CPTCFG_MAC80211_DEBUGFS) += rc80211_minstrel_ht_debugfs.o
+rc80211_minstrel-$(CPTCFG_MAC80211_DEBUGFS) += \
+	rc80211_minstrel_debugfs.o \
+	rc80211_minstrel_ht_debugfs.o
 
 mac80211-$(CPTCFG_MAC80211_RC_MINSTREL) += $(rc80211_minstrel-y)
-mac80211-$(CPTCFG_MAC80211_RC_MINSTREL_HT) += $(rc80211_minstrel_ht-y)
 
 ccflags-y += -DDEBUG
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -1308,18 +1308,12 @@ static int __init ieee80211_init(void)
 	if (ret)
 		return ret;
 
-	ret = rc80211_minstrel_ht_init();
-	if (ret)
-		goto err_minstrel;
-
 	ret = ieee80211_iface_init();
 	if (ret)
 		goto err_netdev;
 
 	return 0;
  err_netdev:
-	rc80211_minstrel_ht_exit();
- err_minstrel:
 	rc80211_minstrel_exit();
 
 	return ret;
@@ -1327,7 +1321,6 @@ static int __init ieee80211_init(void)
 
 static void __exit ieee80211_exit(void)
 {
-	rc80211_minstrel_ht_exit();
 	rc80211_minstrel_exit();
 
 	ieee80211s_stop();
--- a/net/mac80211/rate.h
+++ b/net/mac80211/rate.h
@@ -95,18 +95,5 @@ static inline void rc80211_minstrel_exit
 }
 #endif
 
-#ifdef CPTCFG_MAC80211_RC_MINSTREL_HT
-int rc80211_minstrel_ht_init(void);
-void rc80211_minstrel_ht_exit(void);
-#else
-static inline int rc80211_minstrel_ht_init(void)
-{
-	return 0;
-}
-static inline void rc80211_minstrel_ht_exit(void)
-{
-}
-#endif
-
 
 #endif /* IEEE80211_RATE_H */
--- a/net/mac80211/rc80211_minstrel.c
+++ b/net/mac80211/rc80211_minstrel.c
@@ -572,138 +572,6 @@ minstrel_rate_init(void *priv, struct ie
 	minstrel_update_rates(mp, mi);
 }
 
-static void *
-minstrel_alloc_sta(void *priv, struct ieee80211_sta *sta, gfp_t gfp)
-{
-	struct ieee80211_supported_band *sband;
-	struct minstrel_sta_info *mi;
-	struct minstrel_priv *mp = priv;
-	struct ieee80211_hw *hw = mp->hw;
-	int max_rates = 0;
-	int i;
-
-	mi = kzalloc(sizeof(struct minstrel_sta_info), gfp);
-	if (!mi)
-		return NULL;
-
-	for (i = 0; i < NUM_NL80211_BANDS; i++) {
-		sband = hw->wiphy->bands[i];
-		if (sband && sband->n_bitrates > max_rates)
-			max_rates = sband->n_bitrates;
-	}
-
-	mi->r = kcalloc(max_rates, sizeof(struct minstrel_rate), gfp);
-	if (!mi->r)
-		goto error;
-
-	mi->sample_table = kmalloc_array(max_rates, SAMPLE_COLUMNS, gfp);
-	if (!mi->sample_table)
-		goto error1;
-
-	mi->last_stats_update = jiffies;
-	return mi;
-
-error1:
-	kfree(mi->r);
-error:
-	kfree(mi);
-	return NULL;
-}
-
-static void
-minstrel_free_sta(void *priv, struct ieee80211_sta *sta, void *priv_sta)
-{
-	struct minstrel_sta_info *mi = priv_sta;
-
-	kfree(mi->sample_table);
-	kfree(mi->r);
-	kfree(mi);
-}
-
-static void
-minstrel_init_cck_rates(struct minstrel_priv *mp)
-{
-	static const int bitrates[4] = { 10, 20, 55, 110 };
-	struct ieee80211_supported_band *sband;
-	u32 rate_flags = ieee80211_chandef_rate_flags(&mp->hw->conf.chandef);
-	int i, j;
-
-	sband = mp->hw->wiphy->bands[NL80211_BAND_2GHZ];
-	if (!sband)
-		return;
-
-	for (i = 0, j = 0; i < sband->n_bitrates; i++) {
-		struct ieee80211_rate *rate = &sband->bitrates[i];
-
-		if (rate->flags & IEEE80211_RATE_ERP_G)
-			continue;
-
-		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
-			continue;
-
-		for (j = 0; j < ARRAY_SIZE(bitrates); j++) {
-			if (rate->bitrate != bitrates[j])
-				continue;
-
-			mp->cck_rates[j] = i;
-			break;
-		}
-	}
-}
-
-static void *
-minstrel_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
-{
-	struct minstrel_priv *mp;
-
-	mp = kzalloc(sizeof(struct minstrel_priv), GFP_ATOMIC);
-	if (!mp)
-		return NULL;
-
-	/* contention window settings
-	 * Just an approximation. Using the per-queue values would complicate
-	 * the calculations and is probably unnecessary */
-	mp->cw_min = 15;
-	mp->cw_max = 1023;
-
-	/* number of packets (in %) to use for sampling other rates
-	 * sample less often for non-mrr packets, because the overhead
-	 * is much higher than with mrr */
-	mp->lookaround_rate = 5;
-	mp->lookaround_rate_mrr = 10;
-
-	/* maximum time that the hw is allowed to stay in one MRR segment */
-	mp->segment_size = 6000;
-
-	if (hw->max_rate_tries > 0)
-		mp->max_retry = hw->max_rate_tries;
-	else
-		/* safe default, does not necessarily have to match hw properties */
-		mp->max_retry = 7;
-
-	if (hw->max_rates >= 4)
-		mp->has_mrr = true;
-
-	mp->hw = hw;
-	mp->update_interval = 100;
-
-#ifdef CPTCFG_MAC80211_DEBUGFS
-	mp->fixed_rate_idx = (u32) -1;
-	debugfs_create_u32("fixed_rate_idx", S_IRUGO | S_IWUGO, debugfsdir,
-			   &mp->fixed_rate_idx);
-#endif
-
-	minstrel_init_cck_rates(mp);
-
-	return mp;
-}
-
-static void
-minstrel_free(void *priv)
-{
-	kfree(priv);
-}
-
 static u32 minstrel_get_expected_throughput(void *priv_sta)
 {
 	struct minstrel_sta_info *mi = priv_sta;
@@ -722,28 +590,8 @@ static u32 minstrel_get_expected_through
 }
 
 const struct rate_control_ops mac80211_minstrel = {
-	.name = "minstrel",
 	.tx_status_ext = minstrel_tx_status,
 	.get_rate = minstrel_get_rate,
 	.rate_init = minstrel_rate_init,
-	.alloc = minstrel_alloc,
-	.free = minstrel_free,
-	.alloc_sta = minstrel_alloc_sta,
-	.free_sta = minstrel_free_sta,
-#ifdef CPTCFG_MAC80211_DEBUGFS
-	.add_sta_debugfs = minstrel_add_sta_debugfs,
-#endif
 	.get_expected_throughput = minstrel_get_expected_throughput,
 };
-
-int __init
-rc80211_minstrel_init(void)
-{
-	return ieee80211_rate_control_register(&mac80211_minstrel);
-}
-
-void
-rc80211_minstrel_exit(void)
-{
-	ieee80211_rate_control_unregister(&mac80211_minstrel);
-}
--- a/net/mac80211/rc80211_minstrel.h
+++ b/net/mac80211/rc80211_minstrel.h
@@ -158,7 +158,5 @@ int minstrel_get_tp_avg(struct minstrel_
 /* debugfs */
 int minstrel_stats_open(struct inode *inode, struct file *file);
 int minstrel_stats_csv_open(struct inode *inode, struct file *file);
-ssize_t minstrel_stats_read(struct file *file, char __user *buf, size_t len, loff_t *ppos);
-int minstrel_stats_release(struct inode *inode, struct file *file);
 
 #endif
--- a/net/mac80211/rc80211_minstrel_debugfs.c
+++ b/net/mac80211/rc80211_minstrel_debugfs.c
@@ -54,22 +54,6 @@
 #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)
 {
@@ -135,14 +119,6 @@ minstrel_stats_open(struct inode *inode,
 	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)
 {
@@ -200,21 +176,3 @@ minstrel_stats_csv_open(struct inode *in
 
 	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;
-
-	debugfs_create_file("rc_stats", S_IRUGO, dir, mi, &minstrel_stat_fops);
-	debugfs_create_file("rc_stats_csv", S_IRUGO, dir, mi,
-			    &minstrel_stat_csv_fops);
-}
--- a/net/mac80211/rc80211_minstrel_ht.c
+++ b/net/mac80211/rc80211_minstrel_ht.c
@@ -137,12 +137,10 @@
 		}					\
 	}
 
-#ifdef CPTCFG_MAC80211_RC_MINSTREL_VHT
 static bool minstrel_vht_only = true;
 module_param(minstrel_vht_only, bool, 0644);
 MODULE_PARM_DESC(minstrel_vht_only,
 		 "Use only VHT rates when VHT is supported by sta.");
-#endif
 
 /*
  * To enable sufficiently targeted rate sampling, MCS rates are divided into
@@ -171,7 +169,6 @@ const struct mcs_group minstrel_mcs_grou
 
 	CCK_GROUP,
 
-#ifdef CPTCFG_MAC80211_RC_MINSTREL_VHT
 	VHT_GROUP(1, 0, BW_20),
 	VHT_GROUP(2, 0, BW_20),
 	VHT_GROUP(3, 0, BW_20),
@@ -195,7 +192,6 @@ const struct mcs_group minstrel_mcs_grou
 	VHT_GROUP(1, 1, BW_80),
 	VHT_GROUP(2, 1, BW_80),
 	VHT_GROUP(3, 1, BW_80),
-#endif
 };
 
 static u8 sample_table[SAMPLE_COLUMNS][MCS_GROUP_RATES] __read_mostly;
@@ -1146,12 +1142,10 @@ minstrel_ht_update_caps(void *priv, stru
 
 	BUILD_BUG_ON(ARRAY_SIZE(minstrel_mcs_groups) != MINSTREL_GROUPS_NB);
 
-#ifdef CPTCFG_MAC80211_RC_MINSTREL_VHT
 	if (vht_cap->vht_supported)
 		use_vht = vht_cap->vht_mcs.tx_mcs_map != cpu_to_le16(~0);
 	else
-#endif
-	use_vht = 0;
+		use_vht = 0;
 
 	msp->is_ht = true;
 	memset(mi, 0, sizeof(*mi));
@@ -1226,10 +1220,9 @@ minstrel_ht_update_caps(void *priv, stru
 
 		/* HT rate */
 		if (gflags & IEEE80211_TX_RC_MCS) {
-#ifdef CPTCFG_MAC80211_RC_MINSTREL_VHT
 			if (use_vht && minstrel_vht_only)
 				continue;
-#endif
+
 			mi->supported[i] = mcs->rx_mask[nss - 1];
 			if (mi->supported[i])
 				n_supported++;
@@ -1349,16 +1342,88 @@ minstrel_ht_free_sta(void *priv, struct
 	kfree(msp);
 }
 
+static void
+minstrel_ht_init_cck_rates(struct minstrel_priv *mp)
+{
+	static const int bitrates[4] = { 10, 20, 55, 110 };
+	struct ieee80211_supported_band *sband;
+	u32 rate_flags = ieee80211_chandef_rate_flags(&mp->hw->conf.chandef);
+	int i, j;
+
+	sband = mp->hw->wiphy->bands[NL80211_BAND_2GHZ];
+	if (!sband)
+		return;
+
+	for (i = 0, j = 0; i < sband->n_bitrates; i++) {
+		struct ieee80211_rate *rate = &sband->bitrates[i];
+
+		if (rate->flags & IEEE80211_RATE_ERP_G)
+			continue;
+
+		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
+			continue;
+
+		for (j = 0; j < ARRAY_SIZE(bitrates); j++) {
+			if (rate->bitrate != bitrates[j])
+				continue;
+
+			mp->cck_rates[j] = i;
+			break;
+		}
+	}
+}
+
 static void *
 minstrel_ht_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
 {
-	return mac80211_minstrel.alloc(hw, debugfsdir);
+	struct minstrel_priv *mp;
+
+	mp = kzalloc(sizeof(struct minstrel_priv), GFP_ATOMIC);
+	if (!mp)
+		return NULL;
+
+	/* contention window settings
+	 * Just an approximation. Using the per-queue values would complicate
+	 * the calculations and is probably unnecessary */
+	mp->cw_min = 15;
+	mp->cw_max = 1023;
+
+	/* number of packets (in %) to use for sampling other rates
+	 * sample less often for non-mrr packets, because the overhead
+	 * is much higher than with mrr */
+	mp->lookaround_rate = 5;
+	mp->lookaround_rate_mrr = 10;
+
+	/* maximum time that the hw is allowed to stay in one MRR segment */
+	mp->segment_size = 6000;
+
+	if (hw->max_rate_tries > 0)
+		mp->max_retry = hw->max_rate_tries;
+	else
+		/* safe default, does not necessarily have to match hw properties */
+		mp->max_retry = 7;
+
+	if (hw->max_rates >= 4)
+		mp->has_mrr = true;
+
+	mp->hw = hw;
+	mp->update_interval = 100;
+
+#ifdef CPTCFG_MAC80211_DEBUGFS
+	mp->fixed_rate_idx = (u32) -1;
+	debugfs_create_u32("fixed_rate_idx", S_IRUGO | S_IWUGO, debugfsdir,
+			   &mp->fixed_rate_idx);
+#endif
+
+	minstrel_ht_init_cck_rates(mp);
+
+	return mp;
 }
 
 static void
 minstrel_ht_free(void *priv)
 {
-	mac80211_minstrel.free(priv);
+	kfree(priv);
 }
 
 static u32 minstrel_ht_get_expected_throughput(void *priv_sta)
@@ -1417,14 +1482,14 @@ static void __init init_sample_table(voi
 }
 
 int __init
-rc80211_minstrel_ht_init(void)
+rc80211_minstrel_init(void)
 {
 	init_sample_table();
 	return ieee80211_rate_control_register(&mac80211_minstrel_ht);
 }
 
 void
-rc80211_minstrel_ht_exit(void)
+rc80211_minstrel_exit(void)
 {
 	ieee80211_rate_control_unregister(&mac80211_minstrel_ht);
 }
--- a/net/mac80211/rc80211_minstrel_ht.h
+++ b/net/mac80211/rc80211_minstrel_ht.h
@@ -15,11 +15,7 @@
  */
 #define MINSTREL_MAX_STREAMS		3
 #define MINSTREL_HT_STREAM_GROUPS	4 /* BW(=2) * SGI(=2) */
-#ifdef CPTCFG_MAC80211_RC_MINSTREL_VHT
 #define MINSTREL_VHT_STREAM_GROUPS	6 /* BW(=3) * SGI(=2) */
-#else
-#define MINSTREL_VHT_STREAM_GROUPS	0
-#endif
 
 #define MINSTREL_HT_GROUPS_NB	(MINSTREL_MAX_STREAMS *		\
 				 MINSTREL_HT_STREAM_GROUPS)
@@ -34,11 +30,7 @@
 #define MINSTREL_CCK_GROUP	(MINSTREL_HT_GROUP_0 + MINSTREL_HT_GROUPS_NB)
 #define MINSTREL_VHT_GROUP_0	(MINSTREL_CCK_GROUP + 1)
 
-#ifdef CPTCFG_MAC80211_RC_MINSTREL_VHT
 #define MCS_GROUP_RATES		10
-#else
-#define MCS_GROUP_RATES		8
-#endif
 
 struct mcs_group {
 	u32 flags;
--- a/net/mac80211/rc80211_minstrel_ht_debugfs.c
+++ b/net/mac80211/rc80211_minstrel_ht_debugfs.c
@@ -15,6 +15,22 @@
 #include "rc80211_minstrel.h"
 #include "rc80211_minstrel_ht.h"
 
+static 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);
+}
+
+static int
+minstrel_stats_release(struct inode *inode, struct file *file)
+{
+	kfree(file->private_data);
+	return 0;
+}
+
 static char *
 minstrel_ht_stats_dump(struct minstrel_ht_sta *mi, int i, char *p)
 {
