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: Marcel Holtmann <marcel@holtmann.org>

6 files changed, 114 insertions, 88 deletions

diff --git a/include/net/bluetooth/bluetooth.h b/include/net/bluetooth/bluetooth.h
index 04a6908e38d..ff77e8f882f 100644
--- a/include/net/bluetooth/bluetooth.h
+++ b/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 */
diff --git a/net/bluetooth/hci_sysfs.c b/net/bluetooth/hci_sysfs.c
index cafb55b0cea..05fd125f74f 100644
--- a/net/bluetooth/hci_sysfs.c
+++ b/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);
diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c
index 27551820741..43e17f7d7ec 100644
--- a/net/bluetooth/l2cap.c
+++ b/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 @@ drop:
         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 @@ error:
 
 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");
diff --git a/net/bluetooth/rfcomm/core.c b/net/bluetooth/rfcomm/core.c
index cf164073269..13f114e8b0f 100644
--- a/net/bluetooth/rfcomm/core.c
+++ b/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();