Bluetooth: Convert debug files to actually use debugfs instead of sysfs

Some of the debug files ended up wrongly in sysfs, because at that point
of time, debugfs didn't exist. Convert these files to use debugfs and
also seq_file. This patch converts all of these files at once and then
removes the exported symbol for the Bluetooth sysfs class.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

include/net/bluetooth/bluetooth.h

@@ -176,6 +176,6 @@ extern void hci_sock_cleanup(void);
 extern int bt_sysfs_init(void);
 extern void bt_sysfs_cleanup(void);
 
-extern struct class *bt_class;
+extern struct dentry *bt_debugfs;
 
 #endif /* __BLUETOOTH_H */

net/bluetooth/hci_sysfs.c

@@ -8,8 +8,7 @@
 #include <net/bluetooth/bluetooth.h>
 #include <net/bluetooth/hci_core.h>
 
-struct class *bt_class = NULL;
-EXPORT_SYMBOL_GPL(bt_class);
+static struct class *bt_class;
 
 struct dentry *bt_debugfs = NULL;
 EXPORT_SYMBOL_GPL(bt_debugfs);

net/bluetooth/l2cap.c

@@ -40,6 +40,8 @@
 #include <linux/skbuff.h>
 #include <linux/list.h>
 #include <linux/device.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
 #include <linux/uaccess.h>
 #include <linux/crc16.h>
 #include <net/sock.h>
@@ -3937,39 +3939,42 @@ static int l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 fl
 	return 0;
 }
 
-static ssize_t l2cap_sysfs_show(struct class *dev,
-				struct class_attribute *attr,
-				char *buf)
+static int l2cap_debugfs_show(struct seq_file *f, void *p)
 {
 	struct sock *sk;
 	struct hlist_node *node;
-	char *str = buf;
-	int size = PAGE_SIZE;
 
 	read_lock_bh(&l2cap_sk_list.lock);
 
 	sk_for_each(sk, node, &l2cap_sk_list.head) {
 		struct l2cap_pinfo *pi = l2cap_pi(sk);
-		int len;
-
-		len = snprintf(str, size, "%s %s %d %d 0x%4.4x 0x%4.4x %d %d %d\n",
-				batostr(&bt_sk(sk)->src), batostr(&bt_sk(sk)->dst),
-				sk->sk_state, __le16_to_cpu(pi->psm), pi->scid,
-				pi->dcid, pi->imtu, pi->omtu, pi->sec_level);
-
-		size -= len;
-		if (size <= 0)
-			break;
 
-		str += len;
+		seq_printf(f, "%s %s %d %d 0x%4.4x 0x%4.4x %d %d %d\n",
+					batostr(&bt_sk(sk)->src),
+					batostr(&bt_sk(sk)->dst),
+					sk->sk_state, __le16_to_cpu(pi->psm),
+					pi->scid, pi->dcid,
+					pi->imtu, pi->omtu, pi->sec_level);
 	}
 
 	read_unlock_bh(&l2cap_sk_list.lock);
 
-	return str - buf;
+	return 0;
 }
 
-static CLASS_ATTR(l2cap, S_IRUGO, l2cap_sysfs_show, NULL);
+static int l2cap_debugfs_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, l2cap_debugfs_show, inode->i_private);
+}
+
+static const struct file_operations l2cap_debugfs_fops = {
+	.open		= l2cap_debugfs_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static struct dentry *l2cap_debugfs;
 
 static const struct proto_ops l2cap_sock_ops = {
 	.family		= PF_BLUETOOTH,
@@ -4029,8 +4034,12 @@ static int __init l2cap_init(void)
 		goto error;
 	}
 
-	if (class_create_file(bt_class, &class_attr_l2cap) < 0)
-		BT_ERR("Failed to create L2CAP info file");
+	if (bt_debugfs) {
+		l2cap_debugfs = debugfs_create_file("l2cap", 0444,
+					bt_debugfs, NULL, &l2cap_debugfs_fops);
+		if (!l2cap_debugfs)
+			BT_ERR("Failed to create L2CAP debug file");
+	}
 
 	BT_INFO("L2CAP ver %s", VERSION);
 	BT_INFO("L2CAP socket layer initialized");
@@ -4044,7 +4053,7 @@ static int __init l2cap_init(void)
 
 static void __exit l2cap_exit(void)
 {
-	class_remove_file(bt_class, &class_attr_l2cap);
+	debugfs_remove(l2cap_debugfs);
 
 	if (bt_sock_unregister(BTPROTO_L2CAP) < 0)
 		BT_ERR("L2CAP socket unregistration failed");

net/bluetooth/rfcomm/core.c

@@ -33,6 +33,8 @@
 #include <linux/init.h>
 #include <linux/wait.h>
 #include <linux/device.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
 #include <linux/net.h>
 #include <linux/mutex.h>
 #include <linux/kthread.h>
@@ -2098,14 +2100,10 @@ static struct hci_cb rfcomm_cb = {
 	.security_cfm	= rfcomm_security_cfm
 };
 
-static ssize_t rfcomm_dlc_sysfs_show(struct class *dev,
-				     struct class_attribute *attr,
-				     char *buf)
+static int rfcomm_dlc_debugfs_show(struct seq_file *f, void *x)
 {
 	struct rfcomm_session *s;
 	struct list_head *pp, *p;
-	char *str = buf;
-	int size = PAGE_SIZE;
 
 	rfcomm_lock();
 
@@ -2114,29 +2112,33 @@ static ssize_t rfcomm_dlc_sysfs_show(struct class *dev,
 		list_for_each(pp, &s->dlcs) {
 			struct sock *sk = s->sock->sk;
 			struct rfcomm_dlc *d = list_entry(pp, struct rfcomm_dlc, list);
-			int len;
 
-			len = snprintf(str, size, "%s %s %ld %d %d %d %d\n",
-					batostr(&bt_sk(sk)->src), batostr(&bt_sk(sk)->dst),
-					d->state, d->dlci, d->mtu, d->rx_credits, d->tx_credits);
-
-			size -= len;
-			if (size <= 0)
-				break;
-
-			str += len;
+			seq_printf(f, "%s %s %ld %d %d %d %d\n",
+						batostr(&bt_sk(sk)->src),
+						batostr(&bt_sk(sk)->dst),
+						d->state, d->dlci, d->mtu,
+						d->rx_credits, d->tx_credits);
 		}
-
-		if (size <= 0)
-			break;
 	}
 
 	rfcomm_unlock();
 
-	return (str - buf);
+	return 0;
+}
+
+static int rfcomm_dlc_debugfs_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, rfcomm_dlc_debugfs_show, inode->i_private);
 }
 
-static CLASS_ATTR(rfcomm_dlc, S_IRUGO, rfcomm_dlc_sysfs_show, NULL);
+static const struct file_operations rfcomm_dlc_debugfs_fops = {
+	.open		= rfcomm_dlc_debugfs_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static struct dentry *rfcomm_dlc_debugfs;
 
 /* ---- Initialization ---- */
 static int __init rfcomm_init(void)
@@ -2153,8 +2155,12 @@ static int __init rfcomm_init(void)
 		goto unregister;
 	}
 
-	if (class_create_file(bt_class, &class_attr_rfcomm_dlc) < 0)
-		BT_ERR("Failed to create RFCOMM info file");
+	if (bt_debugfs) {
+		rfcomm_dlc_debugfs = debugfs_create_file("rfcomm_dlc", 0444,
+				bt_debugfs, NULL, &rfcomm_dlc_debugfs_fops);
+		if (!rfcomm_dlc_debugfs)
+			BT_ERR("Failed to create RFCOMM debug file");
+	}
 
 	err = rfcomm_init_ttys();
 	if (err < 0)
@@ -2182,7 +2188,7 @@ static int __init rfcomm_init(void)
 
 static void __exit rfcomm_exit(void)
 {
-	class_remove_file(bt_class, &class_attr_rfcomm_dlc);
+	debugfs_remove(rfcomm_dlc_debugfs);
 
 	hci_unregister_cb(&rfcomm_cb);
 

net/bluetooth/rfcomm/sock.c

@@ -40,6 +40,8 @@
 #include <linux/skbuff.h>
 #include <linux/list.h>
 #include <linux/device.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
 #include <net/sock.h>
 
 #include <asm/system.h>
@@ -1061,37 +1063,38 @@ int rfcomm_connect_ind(struct rfcomm_session *s, u8 channel, struct rfcomm_dlc *
 	return result;
 }
 
-static ssize_t rfcomm_sock_sysfs_show(struct class *dev,
-				      struct class_attribute *attr,
-				      char *buf)
+static int rfcomm_sock_debugfs_show(struct seq_file *f, void *p)
 {
 	struct sock *sk;
 	struct hlist_node *node;
-	char *str = buf;
-	int size = PAGE_SIZE;
 
 	read_lock_bh(&rfcomm_sk_list.lock);
 
 	sk_for_each(sk, node, &rfcomm_sk_list.head) {
-		int len;
-
-		len = snprintf(str, size, "%s %s %d %d\n",
-				batostr(&bt_sk(sk)->src), batostr(&bt_sk(sk)->dst),
+		seq_printf(f, "%s %s %d %d\n",
+				batostr(&bt_sk(sk)->src),
+				batostr(&bt_sk(sk)->dst),
 				sk->sk_state, rfcomm_pi(sk)->channel);
-
-		size -= len;
-		if (size <= 0)
-			break;
-
-		str += len;
 	}
 
 	read_unlock_bh(&rfcomm_sk_list.lock);
 
-	return (str - buf);
+	return 0;
 }
 
-static CLASS_ATTR(rfcomm, S_IRUGO, rfcomm_sock_sysfs_show, NULL);
+static int rfcomm_sock_debugfs_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, rfcomm_sock_debugfs_show, inode->i_private);
+}
+
+static const struct file_operations rfcomm_sock_debugfs_fops = {
+	.open		= rfcomm_sock_debugfs_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static struct dentry *rfcomm_sock_debugfs;
 
 static const struct proto_ops rfcomm_sock_ops = {
 	.family		= PF_BLUETOOTH,
@@ -1131,8 +1134,12 @@ int __init rfcomm_init_sockets(void)
 	if (err < 0)
 		goto error;
 
-	if (class_create_file(bt_class, &class_attr_rfcomm) < 0)
-		BT_ERR("Failed to create RFCOMM info file");
+	if (bt_debugfs) {
+		rfcomm_sock_debugfs = debugfs_create_file("rfcomm", 0444,
+				bt_debugfs, NULL, &rfcomm_sock_debugfs_fops);
+		if (!rfcomm_sock_debugfs)
+			BT_ERR("Failed to create RFCOMM debug file");
+	}
 
 	BT_INFO("RFCOMM socket layer initialized");
 
@@ -1146,7 +1153,7 @@ int __init rfcomm_init_sockets(void)
 
 void rfcomm_cleanup_sockets(void)
 {
-	class_remove_file(bt_class, &class_attr_rfcomm);
+	debugfs_remove(rfcomm_sock_debugfs);
 
 	if (bt_sock_unregister(BTPROTO_RFCOMM) < 0)
 		BT_ERR("RFCOMM socket layer unregistration failed");

net/bluetooth/sco.c

@@ -38,6 +38,8 @@
 #include <linux/socket.h>
 #include <linux/skbuff.h>
 #include <linux/device.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
 #include <linux/list.h>
 #include <net/sock.h>
 
@@ -953,37 +955,36 @@ static int sco_recv_scodata(struct hci_conn *hcon, struct sk_buff *skb)
 	return 0;
 }
 
-static ssize_t sco_sysfs_show(struct class *dev,
-				struct class_attribute *attr,
-				char *buf)
+static int sco_debugfs_show(struct seq_file *f, void *p)
 {
 	struct sock *sk;
 	struct hlist_node *node;
-	char *str = buf;
-	int size = PAGE_SIZE;
 
 	read_lock_bh(&sco_sk_list.lock);
 
 	sk_for_each(sk, node, &sco_sk_list.head) {
-		int len;
-
-		len = snprintf(str, size, "%s %s %d\n",
-				batostr(&bt_sk(sk)->src), batostr(&bt_sk(sk)->dst),
-				sk->sk_state);
-
-		size -= len;
-		if (size <= 0)
-			break;
-
-		str += len;
+		seq_printf(f, "%s %s %d\n", batostr(&bt_sk(sk)->src),
+				batostr(&bt_sk(sk)->dst), sk->sk_state);
 	}
 
 	read_unlock_bh(&sco_sk_list.lock);
 
-	return (str - buf);
+	return 0;
 }
 
-static CLASS_ATTR(sco, S_IRUGO, sco_sysfs_show, NULL);
+static int sco_debugfs_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, sco_debugfs_show, inode->i_private);
+}
+
+static const struct file_operations sco_debugfs_fops = {
+	.open		= sco_debugfs_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static struct dentry *sco_debugfs;
 
 static const struct proto_ops sco_sock_ops = {
 	.family		= PF_BLUETOOTH,
@@ -1041,8 +1042,12 @@ static int __init sco_init(void)
 		goto error;
 	}
 
-	if (class_create_file(bt_class, &class_attr_sco) < 0)
-		BT_ERR("Failed to create SCO info file");
+	if (bt_debugfs) {
+		sco_debugfs = debugfs_create_file("sco", 0444,
+					bt_debugfs, NULL, &sco_debugfs_fops);
+		if (!sco_debugfs)
+			BT_ERR("Failed to create SCO debug file");
+	}
 
 	BT_INFO("SCO (Voice Link) ver %s", VERSION);
 	BT_INFO("SCO socket layer initialized");
@@ -1056,7 +1061,7 @@ static int __init sco_init(void)
 
 static void __exit sco_exit(void)
 {
-	class_remove_file(bt_class, &class_attr_sco);
+	debugfs_remove(sco_debugfs);
 
 	if (bt_sock_unregister(BTPROTO_SCO) < 0)
 		BT_ERR("SCO socket unregistration failed");