l2tp: cleanup comments
authorTom Parkin <tparkin@katalix.com>
Wed, 22 Jul 2020 16:32:06 +0000 (17:32 +0100)
committerDavid S. Miller <davem@davemloft.net>
Thu, 23 Jul 2020 01:08:39 +0000 (18:08 -0700)
Modify some l2tp comments to better adhere to kernel coding style, as
reported by checkpatch.pl.

Add descriptive comments for the l2tp per-net spinlocks to document
their use.

Fix an incorrect comment in l2tp_recv_common:

RFC2661 section 5.4 states that:

"The LNS controls enabling and disabling of sequence numbers by sending a
data message with or without sequence numbers present at any time during
the life of a session."

l2tp handles this correctly in l2tp_recv_common, but the comment around
the code was incorrect and confusing.  Fix up the comment accordingly.

Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/l2tp/l2tp_core.c
net/l2tp/l2tp_core.h
net/l2tp/l2tp_debugfs.c
net/l2tp/l2tp_eth.c
net/l2tp/l2tp_ip.c
net/l2tp/l2tp_ip6.c
net/l2tp/l2tp_netlink.c
net/l2tp/l2tp_ppp.c

index 0992d5f..f5e314d 100644 (file)
@@ -1,6 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0-only
-/*
- * L2TP core.
+/* L2TP core.
  *
  * Copyright (c) 2008,2009,2010 Katalix Systems Ltd
  *
@@ -102,8 +101,10 @@ static struct workqueue_struct *l2tp_wq;
 static unsigned int l2tp_net_id;
 struct l2tp_net {
        struct list_head l2tp_tunnel_list;
+       /* Lock for write access to l2tp_tunnel_list */
        spinlock_t l2tp_tunnel_list_lock;
        struct hlist_head l2tp_session_hlist[L2TP_HASH_SIZE_2];
+       /* Lock for write access to l2tp_session_hlist */
        spinlock_t l2tp_session_hlist_lock;
 };
 
@@ -678,7 +679,7 @@ void l2tp_recv_common(struct l2tp_session *session, struct sk_buff *skb,
        }
 
        if (L2TP_SKB_CB(skb)->has_seq) {
-               /* Received a packet with sequence numbers. If we're the LNS,
+               /* Received a packet with sequence numbers. If we're the LAC,
                 * check if we sre sending sequence numbers and if not,
                 * configure it so.
                 */
@@ -1604,7 +1605,7 @@ void __l2tp_session_unhash(struct l2tp_session *session)
 EXPORT_SYMBOL_GPL(__l2tp_session_unhash);
 
 /* This function is used by the netlink SESSION_DELETE command and by
  pseudowire modules.
* pseudowire modules.
  */
 int l2tp_session_delete(struct l2tp_session *session)
 {
index 10cf7c3..3ebb701 100644 (file)
@@ -1,6 +1,5 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * L2TP internal definitions.
+/* L2TP internal definitions.
  *
  * Copyright (c) 2008,2009 Katalix Systems Ltd
  */
@@ -49,32 +48,26 @@ struct l2tp_tunnel;
  */
 struct l2tp_session_cfg {
        enum l2tp_pwtype        pw_type;
-       unsigned int            recv_seq:1;     /* expect receive packets with
-                                                * sequence numbers? */
-       unsigned int            send_seq:1;     /* send packets with sequence
-                                                * numbers? */
-       unsigned int            lns_mode:1;     /* behave as LNS? LAC enables
-                                                * sequence numbers under
-                                                * control of LNS. */
-       int                     debug;          /* bitmask of debug message
-                                                * categories */
+       unsigned int            recv_seq:1;     /* expect receive packets with sequence numbers? */
+       unsigned int            send_seq:1;     /* send packets with sequence numbers? */
+       unsigned int            lns_mode:1;     /* behave as LNS?
+                                                * LAC enables sequence numbers under LNS control.
+                                                */
+       int                     debug;          /* bitmask of debug message categories */
        u16                     l2specific_type; /* Layer 2 specific type */
        u8                      cookie[8];      /* optional cookie */
        int                     cookie_len;     /* 0, 4 or 8 bytes */
        u8                      peer_cookie[8]; /* peer's cookie */
        int                     peer_cookie_len; /* 0, 4 or 8 bytes */
-       int                     reorder_timeout; /* configured reorder timeout
-                                                 * (in jiffies) */
+       int                     reorder_timeout; /* configured reorder timeout (in jiffies) */
        char                    *ifname;
 };
 
 struct l2tp_session {
-       int                     magic;          /* should be
-                                                * L2TP_SESSION_MAGIC */
+       int                     magic;          /* should be L2TP_SESSION_MAGIC */
        long                    dead;
 
-       struct l2tp_tunnel      *tunnel;        /* back pointer to tunnel
-                                                * context */
+       struct l2tp_tunnel      *tunnel;        /* back pointer to tunnel context */
        u32                     session_id;
        u32                     peer_session_id;
        u8                      cookie[8];
@@ -89,42 +82,37 @@ struct l2tp_session {
        u32                     nr_max;         /* max NR. Depends on tunnel */
        u32                     nr_window_size; /* NR window size */
        u32                     nr_oos;         /* NR of last OOS packet */
-       int                     nr_oos_count;   /* For OOS recovery */
+       int                     nr_oos_count;   /* for OOS recovery */
        int                     nr_oos_count_max;
-       struct hlist_node       hlist;          /* Hash list node */
+       struct hlist_node       hlist;          /* hash list node */
        refcount_t              ref_count;
 
        char                    name[32];       /* for logging */
        char                    ifname[IFNAMSIZ];
-       unsigned int            recv_seq:1;     /* expect receive packets with
-                                                * sequence numbers? */
-       unsigned int            send_seq:1;     /* send packets with sequence
-                                                * numbers? */
-       unsigned int            lns_mode:1;     /* behave as LNS? LAC enables
-                                                * sequence numbers under
-                                                * control of LNS. */
-       int                     debug;          /* bitmask of debug message
-                                                * categories */
-       int                     reorder_timeout; /* configured reorder timeout
-                                                 * (in jiffies) */
+       unsigned int            recv_seq:1;     /* expect receive packets with sequence numbers? */
+       unsigned int            send_seq:1;     /* send packets with sequence numbers? */
+       unsigned int            lns_mode:1;     /* behave as LNS?
+                                                * LAC enables sequence numbers under LNS control.
+                                                */
+       int                     debug;          /* bitmask of debug message categories */
+       int                     reorder_timeout; /* configured reorder timeout (in jiffies) */
        int                     reorder_skip;   /* set if skip to next nr */
        enum l2tp_pwtype        pwtype;
        struct l2tp_stats       stats;
-       struct hlist_node       global_hlist;   /* Global hash list node */
+       struct hlist_node       global_hlist;   /* global hash list node */
 
        int (*build_header)(struct l2tp_session *session, void *buf);
        void (*recv_skb)(struct l2tp_session *session, struct sk_buff *skb, int data_len);
        void (*session_close)(struct l2tp_session *session);
        void (*show)(struct seq_file *m, void *priv);
-       u8                      priv[]; /* private data */
+       u8                      priv[];         /* private data */
 };
 
 /* Describes the tunnel. It contains info to track all the associated
  * sessions so incoming packets can be sorted out
  */
 struct l2tp_tunnel_cfg {
-       int                     debug;          /* bitmask of debug message
-                                                * categories */
+       int                     debug;          /* bitmask of debug message categories */
        enum l2tp_encap_type    encap;
 
        /* Used only for kernel-created sockets */
@@ -148,31 +136,29 @@ struct l2tp_tunnel {
 
        struct rcu_head rcu;
        rwlock_t                hlist_lock;     /* protect session_hlist */
-       bool                    acpt_newsess;   /* Indicates whether this
-                                                * tunnel accepts new sessions.
-                                                * Protected by hlist_lock.
+       bool                    acpt_newsess;   /* indicates whether this tunnel accepts
+                                                * new sessions. Protected by hlist_lock.
                                                 */
        struct hlist_head       session_hlist[L2TP_HASH_SIZE];
-                                               /* hashed list of sessions,
-                                                * hashed by id */
+                                               /* hashed list of sessions, hashed by id */
        u32                     tunnel_id;
        u32                     peer_tunnel_id;
        int                     version;        /* 2=>L2TPv2, 3=>L2TPv3 */
 
        char                    name[20];       /* for logging */
-       int                     debug;          /* bitmask of debug message
-                                                * categories */
+       int                     debug;          /* bitmask of debug message categories */
        enum l2tp_encap_type    encap;
        struct l2tp_stats       stats;
 
-       struct list_head        list;           /* Keep a list of all tunnels */
+       struct list_head        list;           /* list node on per-namespace list of tunnels */
        struct net              *l2tp_net;      /* the net we belong to */
 
        refcount_t              ref_count;
        void (*old_sk_destruct)(struct sock *);
-       struct sock             *sock;          /* Parent socket */
-       int                     fd;             /* Parent fd, if tunnel socket
-                                                * was created by userspace */
+       struct sock             *sock;          /* parent socket */
+       int                     fd;             /* parent fd, if tunnel socket was created
+                                                * by userspace
+                                                */
 
        struct work_struct      del_work;
 };
index f0301cb..9318113 100644 (file)
@@ -1,6 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * L2TP subsystem debugfs
+/* L2TP subsystem debugfs
  *
  * Copyright (c) 2010 Katalix Systems Ltd
  */
index a84627d..7ed2b4e 100644 (file)
@@ -1,6 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * L2TPv3 ethernet pseudowire driver
+/* L2TPv3 ethernet pseudowire driver
  *
  * Copyright (c) 2008,2009,2010 Katalix Systems Ltd
  */
index e5b63ea..70f9fda 100644 (file)
@@ -1,6 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * L2TPv3 IP encapsulation support
+/* L2TPv3 IP encapsulation support
  *
  * Copyright (c) 2008,2009,2010 Katalix Systems Ltd
  */
index d17b9fe..ca76961 100644 (file)
@@ -1,6 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * L2TPv3 IP encapsulation support for IPv6
+/* L2TPv3 IP encapsulation support for IPv6
  *
  * Copyright (c) 2012 Katalix Systems Ltd
  */
@@ -38,7 +37,8 @@ struct l2tp_ip6_sock {
        u32                     peer_conn_id;
 
        /* ipv6_pinfo has to be the last member of l2tp_ip6_sock, see
-          inet6_sk_generic */
+        * inet6_sk_generic
+        */
        struct ipv6_pinfo       inet6;
 };
 
@@ -519,7 +519,7 @@ static int l2tp_ip6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
        int err;
 
        /* Rough check on arithmetic overflow,
-          better check is made in ip6_append_data().
+        * better check is made in ip6_append_data().
         */
        if (len > INT_MAX)
                return -EMSGSIZE;
@@ -528,9 +528,7 @@ static int l2tp_ip6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
        if (msg->msg_flags & MSG_OOB)
                return -EOPNOTSUPP;
 
-       /*
-        *      Get and verify the address.
-        */
+       /* Get and verify the address */
        memset(&fl6, 0, sizeof(fl6));
 
        fl6.flowi6_mark = sk->sk_mark;
@@ -555,8 +553,7 @@ static int l2tp_ip6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
                        }
                }
 
-               /*
-                * Otherwise it will be difficult to maintain
+               /* Otherwise it will be difficult to maintain
                 * sk->sk_dst_cache.
                 */
                if (sk->sk_state == TCP_ESTABLISHED &&
index 0ce8e94..3120f8d 100644 (file)
@@ -1,6 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0-only
-/*
- * L2TP netlink layer, for management
+/* L2TP netlink layer, for management
  *
  * Copyright (c) 2008,2009,2010 Katalix Systems Ltd
  *
index 6dccffa..48fbaf5 100644 (file)
@@ -117,8 +117,7 @@ struct pppol2tp_session {
        int                     owner;          /* pid that opened the socket */
 
        struct mutex            sk_lock;        /* Protects .sk */
-       struct sock __rcu       *sk;            /* Pointer to the session
-                                                * PPPoX socket */
+       struct sock __rcu       *sk;            /* Pointer to the session PPPoX socket */
        struct sock             *__sk;          /* Copy of .sk, for cleanup */
        struct rcu_head         rcu;            /* For asynchronous release */
 };