[PATCH bluetooth-next 0/4] 6lowpan: introduce generic 6lowpan private data

[PATCH bluetooth-next 0/4] 6lowpan: introduce generic 6lowpan private data

[Alexander Aring]

Hi,

I already thought many times to introduce something like that. Here is a draft
for introducing the generic 6lowpan private data into each lowpan interface.
For the beginning I introduced the enum "lltype" which contains the LL type of
a lowpan interface.

Use cases for such feature (LL types):

 - If we do in upper layers (6LoWPAN/IPv6) a evaluation of dev->type then
   the value is on all lowpan interfaces "APRHRD_6LOWPAN". If we checked on
   "dev->type" and it's ARPHRD_6LOWPAN we can safe use lowpan_priv to get
   6LoWPAN generic private data. With this data we can check the LL type which
   can be currently BTLE or IEEE802154. This could be useful to make different
   handling in iphc compress/decompress and evaluating LL private data of skb
   control block "skb->cb".

   Example (802.15.4 has different address handling functionality):

   switch (lowpan_priv(dev)->lltype) {
   case LOWPAN_LLTYPE_BTLE:
        /* do EUI64 btle handling */
        break;
   case LOWPAN_LLTYPE_IEEE802154:
        /* do complicated short/extended address handling */
        /* we can surely call skb->cb to some other private data from LL
           which was set before iphc compress/decompress function call */
        break;
   }

   The handling is currently for 802.15.4 is in generic 6lowpan code currently
   not quite. This should be handled by private data. At the moment btle use
   the same handling like for 802.15.4 extended address. Nevertheless is we can
   cleanup some handling then in generic iphc functionality.

   This also possible in layers like IPv6, just doing a check on APRHRD_6LOWPAN
   before calling lowpan_priv(dev)->lltype, then we are sure that the private
   data of the interface is a 6LoWPAN interface and we can cast it to lowpan_priv.
   Then we can do 6LoWPAN generic stuff OR 6lowpan specific LL stuff.

 - In Lukasz Duda RFC for introducing stateful address compression, I saw
   some behaviour which such functionality is also useful. Currently we don't
   have a allocated space for a 6LoWPAN generic space which is assigned to a
   lowpan interface. When LL layers (BTLE, IEEE802154) calls iphc
   compress/decompress Lukasz had no change to access some room which is needed
   for storing the context information into a table. The workaround for this
   feature was to add allocate a static data room for the table and doing a
   lookup/match of netdev name. Which a generic 6lowpan private data room per each
   lowpan interface we can put this table according to the netdev private room,
   which means in short: no lookup is needed anymore, just dereferencing lowpan_priv.

   In upper layer like IPv6 Lukasz could use that to get the stateful context
   table information as an example for doing 6LoWPAN generic stuff in upper
   layers.


Note about the implementation for LL 6LoWPAN private pointer:

I stole some mechanism from wireless for that. See [0], the vif struct is part
of sdata which is also part of private data of a wireless interface (mac80211).
I hope I can just adapt this behaviour.

- Alex

Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org

[0] http://lxr.free-electrons.com/source/include/net/mac80211.h#L1366

changes since PATCH (was RFC before):
 - rename ll_type,ll_foo to lltype, llfoo
 - add documentation for generic 6lowpan interfaces API
 - add net/6lowpan/core.c for core functionality, like setup or cleanup
   lowpan netdev interfaces, which is necessary e.g. heap allocation/free
 - add LOWPAN_PRIV_SIZE for provide API functionality to calculate
   private data
 - rebase to current bluetooth-next/master
 - add documentation in cc for the Documentation branch

changes since v2:
 - rename L2/l2 to LL/ll. I think the usually word in ietf for L2 is
   LL which means "link layer". Also ipv6 stack use ll for variables like
   lladdr -> link layer address.
 - rebase to current bluetooth-next/master
 - remove some brackets in function lowpan_priv.

Alexander Aring (4):
  Bluetooth: 6lowpan: change netdev_priv to lowpan_dev
  6lowpan: add generic 6lowpan netdev private data
  6lowpan: move module_init into core functionality
  documentation: networking: add 6lowpan documentation

 Documentation/networking/6lowpan.txt | 51 ++++++++++++++++++++++++++++++++++++
 MAINTAINERS                          |  1 +
 include/net/6lowpan.h                | 23 ++++++++++++++++
 net/6lowpan/Makefile                 |  2 +-
 net/6lowpan/core.c                   | 40 ++++++++++++++++++++++++++++
 net/6lowpan/iphc.c                   | 19 --------------
 net/bluetooth/6lowpan.c              | 11 +++++---
 net/ieee802154/6lowpan/6lowpan_i.h   |  3 ++-
 net/ieee802154/6lowpan/core.c        |  4 ++-
 9 files changed, 128 insertions(+), 26 deletions(-)
 create mode 100644 Documentation/networking/6lowpan.txt
 create mode 100644 net/6lowpan/core.c

-- 
2.5.0

[PATCH bluetooth-next 1/4] Bluetooth: 6lowpan: change netdev_priv to lowpan_dev

[Alexander Aring]

The usually way to get the btle lowpan private data is to use the
introduced lowpan_dev inline function. This patch will cleanup by using
lowpan_dev consequently.

Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
---
 net/bluetooth/6lowpan.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c
index 0ffe2e2..24ed5b0 100644
--- a/net/bluetooth/6lowpan.c
+++ b/net/bluetooth/6lowpan.c
@@ -859,7 +859,7 @@ static int setup_netdev(struct l2cap_chan *chan, struct lowpan_dev **dev)
 	SET_NETDEV_DEV(netdev, &chan->conn->hcon->hdev->dev);
 	SET_NETDEV_DEVTYPE(netdev, &bt_type);
 
-	*dev = netdev_priv(netdev);
+	*dev = lowpan_dev(netdev);
 	(*dev)->netdev = netdev;
 	(*dev)->hdev = chan->conn->hcon->hdev;
 	INIT_LIST_HEAD(&(*dev)->peers);
-- 
2.5.0

[PATCH bluetooth-next 2/4] 6lowpan: add generic 6lowpan netdev private data

[Alexander Aring]

This patch introduced the 6lowpan netdev private data struct. We name it
lowpan_priv and it's placed at the beginning of netdev private data. All
lowpan interfaces should allocate this room at first of netdev private
data. 6LoWPAN LL private data can be allocate by additional netdev private
data, e.g. dev->priv_size should be "sizeof(struct lowpan_priv) +
sizeof(LL_LOWPAN_PRIVATE_DATA)".

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
---
 include/net/6lowpan.h              | 23 +++++++++++++++++++++++
 net/6lowpan/Makefile               |  2 +-
 net/6lowpan/core.c                 | 20 ++++++++++++++++++++
 net/bluetooth/6lowpan.c            |  9 ++++++---
 net/ieee802154/6lowpan/6lowpan_i.h |  3 ++-
 net/ieee802154/6lowpan/core.c      |  4 +++-
 6 files changed, 55 insertions(+), 6 deletions(-)
 create mode 100644 net/6lowpan/core.c

diff --git a/include/net/6lowpan.h b/include/net/6lowpan.h
index dc03d77..a2f59ec 100644
--- a/include/net/6lowpan.h
+++ b/include/net/6lowpan.h
@@ -197,6 +197,27 @@
 #define LOWPAN_NHC_UDP_CS_P_11	0xF3 /* source & dest = 0xF0B + 4bit inline */
 #define LOWPAN_NHC_UDP_CS_C	0x04 /* checksum elided */
 
+#define LOWPAN_PRIV_SIZE(llpriv_size)	\
+	(sizeof(struct lowpan_priv) + llpriv_size)
+
+enum lowpan_lltypes {
+	LOWPAN_LLTYPE_BTLE,
+	LOWPAN_LLTYPE_IEEE802154,
+};
+
+struct lowpan_priv {
+	enum lowpan_lltypes lltype;
+
+	/* must be last */
+	u8 priv[0] __aligned(sizeof(void *));
+};
+
+static inline
+struct lowpan_priv *lowpan_priv(const struct net_device *dev)
+{
+	return netdev_priv(dev);
+}
+
 #ifdef DEBUG
 /* print data in line */
 static inline void raw_dump_inline(const char *caller, char *msg,
@@ -372,6 +393,8 @@ lowpan_uncompress_size(const struct sk_buff *skb, u16 *dgram_offset)
 	return skb->len + uncomp_header - ret;
 }
 
+void lowpan_netdev_setup(struct net_device *dev, enum lowpan_lltypes lltype);
+
 int
 lowpan_header_decompress(struct sk_buff *skb, struct net_device *dev,
 			 const u8 *saddr, const u8 saddr_type,
diff --git a/net/6lowpan/Makefile b/net/6lowpan/Makefile
index eb8baa7..c6ffc55 100644
--- a/net/6lowpan/Makefile
+++ b/net/6lowpan/Makefile
@@ -1,6 +1,6 @@
 obj-$(CONFIG_6LOWPAN) += 6lowpan.o
 
-6lowpan-y := iphc.o nhc.o
+6lowpan-y := core.o iphc.o nhc.o
 
 #rfc6282 nhcs
 obj-$(CONFIG_6LOWPAN_NHC_DEST) += nhc_dest.o
diff --git a/net/6lowpan/core.c b/net/6lowpan/core.c
new file mode 100644
index 0000000..ed0eec9
--- /dev/null
+++ b/net/6lowpan/core.c
@@ -0,0 +1,20 @@
+/* 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * Authors:
+ * (C) 2015 Pengutronix, Alexander Aring <aar@pengutronix.de>
+ */
+
+#include <net/6lowpan.h>
+
+void lowpan_netdev_setup(struct net_device *dev, enum lowpan_lltypes lltype)
+{
+	lowpan_priv(dev)->lltype = lltype;
+}
+EXPORT_SYMBOL(lowpan_netdev_setup);
diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c
index 24ed5b0..131e79c 100644
--- a/net/bluetooth/6lowpan.c
+++ b/net/bluetooth/6lowpan.c
@@ -85,7 +85,7 @@ struct lowpan_dev {
 
 static inline struct lowpan_dev *lowpan_dev(const struct net_device *netdev)
 {
-	return netdev_priv(netdev);
+	return (struct lowpan_dev *)lowpan_priv(netdev)->priv;
 }
 
 static inline void peer_add(struct lowpan_dev *dev, struct lowpan_peer *peer)
@@ -848,8 +848,9 @@ static int setup_netdev(struct l2cap_chan *chan, struct lowpan_dev **dev)
 	struct net_device *netdev;
 	int err = 0;
 
-	netdev = alloc_netdev(sizeof(struct lowpan_dev), IFACE_NAME_TEMPLATE,
-			      NET_NAME_UNKNOWN, netdev_setup);
+	netdev = alloc_netdev(LOWPAN_PRIV_SIZE(sizeof(struct lowpan_dev)),
+			      IFACE_NAME_TEMPLATE, NET_NAME_UNKNOWN,
+			      netdev_setup);
 	if (!netdev)
 		return -ENOMEM;
 
@@ -869,6 +870,8 @@ static int setup_netdev(struct l2cap_chan *chan, struct lowpan_dev **dev)
 	list_add_rcu(&(*dev)->list, &bt_6lowpan_devices);
 	spin_unlock(&devices_lock);
 
+	lowpan_netdev_setup(netdev, LOWPAN_LLTYPE_BTLE);
+
 	err = register_netdev(netdev);
 	if (err < 0) {
 		BT_INFO("register_netdev failed %d", err);
diff --git a/net/ieee802154/6lowpan/6lowpan_i.h b/net/ieee802154/6lowpan/6lowpan_i.h
index 923b680..ea339fa 100644
--- a/net/ieee802154/6lowpan/6lowpan_i.h
+++ b/net/ieee802154/6lowpan/6lowpan_i.h
@@ -5,6 +5,7 @@
 
 #include <net/ieee802154_netdev.h>
 #include <net/inet_frag.h>
+#include <net/6lowpan.h>
 
 struct lowpan_create_arg {
 	u16 tag;
@@ -46,7 +47,7 @@ struct lowpan_dev_info {
 static inline struct
 lowpan_dev_info *lowpan_dev_info(const struct net_device *dev)
 {
-	return netdev_priv(dev);
+	return (struct lowpan_dev_info *)lowpan_priv(dev)->priv;
 }
 
 int lowpan_frag_rcv(struct sk_buff *skb, const u8 frag_type);
diff --git a/net/ieee802154/6lowpan/core.c b/net/ieee802154/6lowpan/core.c
index a4edee8..180e9f5 100644
--- a/net/ieee802154/6lowpan/core.c
+++ b/net/ieee802154/6lowpan/core.c
@@ -138,6 +138,8 @@ static int lowpan_newlink(struct net *src_net, struct net_device *dev,
 	/* Set the lowpan hardware address to the wpan hardware address. */
 	memcpy(dev->dev_addr, real_dev->dev_addr, IEEE802154_ADDR_LEN);
 
+	lowpan_netdev_setup(dev, LOWPAN_LLTYPE_IEEE802154);
+
 	ret = register_netdevice(dev);
 	if (ret >= 0) {
 		real_dev->ieee802154_ptr->lowpan_dev = dev;
@@ -162,7 +164,7 @@ static void lowpan_dellink(struct net_device *dev, struct list_head *head)
 
 static struct rtnl_link_ops lowpan_link_ops __read_mostly = {
 	.kind		= "lowpan",
-	.priv_size	= sizeof(struct lowpan_dev_info),
+	.priv_size	= LOWPAN_PRIV_SIZE(sizeof(struct lowpan_dev_info)),
 	.setup		= lowpan_setup,
 	.newlink	= lowpan_newlink,
 	.dellink	= lowpan_dellink,
-- 
2.5.0

[PATCH bluetooth-next 3/4] 6lowpan: move module_init into core functionality

[Alexander Aring]

This patch moves module_init of 6lowpan module into core functionality
of 6lowpan module. To load the ipv6 module at probing of the 6lowpan
module should be core functionality. Loading next header compression
modules is iphc specific. Nevertheless we only support IPHC for the
generic 6LoWPAN branch right now so we can put it into the core
functionality. If possible new compression formats are introduced nhc
should load only when iphc is build.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
---
 net/6lowpan/core.c | 20 ++++++++++++++++++++
 net/6lowpan/iphc.c | 19 -------------------
 2 files changed, 20 insertions(+), 19 deletions(-)

diff --git a/net/6lowpan/core.c b/net/6lowpan/core.c
index ed0eec9..ae1896f 100644
--- a/net/6lowpan/core.c
+++ b/net/6lowpan/core.c
@@ -11,6 +11,8 @@
  * (C) 2015 Pengutronix, Alexander Aring <aar@pengutronix.de>
  */
 
+#include <linux/module.h>
+
 #include <net/6lowpan.h>
 
 void lowpan_netdev_setup(struct net_device *dev, enum lowpan_lltypes lltype)
@@ -18,3 +20,21 @@ void lowpan_netdev_setup(struct net_device *dev, enum lowpan_lltypes lltype)
 	lowpan_priv(dev)->lltype = lltype;
 }
 EXPORT_SYMBOL(lowpan_netdev_setup);
+
+static int __init lowpan_module_init(void)
+{
+	request_module_nowait("ipv6");
+
+	request_module_nowait("nhc_dest");
+	request_module_nowait("nhc_fragment");
+	request_module_nowait("nhc_hop");
+	request_module_nowait("nhc_ipv6");
+	request_module_nowait("nhc_mobility");
+	request_module_nowait("nhc_routing");
+	request_module_nowait("nhc_udp");
+
+	return 0;
+}
+module_init(lowpan_module_init);
+
+MODULE_LICENSE("GPL");
diff --git a/net/6lowpan/iphc.c b/net/6lowpan/iphc.c
index 74e56d7..1e0071f 100644
--- a/net/6lowpan/iphc.c
+++ b/net/6lowpan/iphc.c
@@ -48,7 +48,6 @@
 
 #include <linux/bitops.h>
 #include <linux/if_arp.h>
-#include <linux/module.h>
 #include <linux/netdevice.h>
 #include <net/6lowpan.h>
 #include <net/ipv6.h>
@@ -610,21 +609,3 @@ int lowpan_header_compress(struct sk_buff *skb, struct net_device *dev,
 	return 0;
 }
 EXPORT_SYMBOL_GPL(lowpan_header_compress);
-
-static int __init lowpan_module_init(void)
-{
-	request_module_nowait("ipv6");
-
-	request_module_nowait("nhc_dest");
-	request_module_nowait("nhc_fragment");
-	request_module_nowait("nhc_hop");
-	request_module_nowait("nhc_ipv6");
-	request_module_nowait("nhc_mobility");
-	request_module_nowait("nhc_routing");
-	request_module_nowait("nhc_udp");
-
-	return 0;
-}
-module_init(lowpan_module_init);
-
-MODULE_LICENSE("GPL");
-- 
2.5.0

[PATCH bluetooth-next 4/4] documentation: networking: add 6lowpan documentation

[Alexander Aring]

This patch adds a 6lowpan.txt into the networking documentation
directory. Currently this documentation describes how the lowpan
private data of net devices will be handled.

Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Suggested-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
---
 Documentation/networking/6lowpan.txt | 51 ++++++++++++++++++++++++++++++++++++
 MAINTAINERS                          |  1 +
 2 files changed, 52 insertions(+)
 create mode 100644 Documentation/networking/6lowpan.txt

diff --git a/Documentation/networking/6lowpan.txt b/Documentation/networking/6lowpan.txt
new file mode 100644
index 0000000..498c81f
--- /dev/null
+++ b/Documentation/networking/6lowpan.txt
@@ -0,0 +1,51 @@
+
+Netdev private dataroom for 6lowpan interfaces:
+
+All 6lowpan able net devices, means all interfaces with ARPHRD_6LOWPAN,
+must have "struct lowpan_priv" placed at beginning of netdev_priv.
+
+The priv_size of each interface should be calculate by:
+
+ dev->priv_size = LOWPAN_PRIV_SIZE(LL_6LOWPAN_PRIV_DATA);
+
+Where LL_PRIV_6LOWPAN_DATA is sizeof linklayer 6lowpan private data struct.
+To access the LL_PRIV_6LOWPAN_DATA structure you can cast:
+
+ lowpan_priv(dev)-priv;
+
+to your LL_6LOWPAN_PRIV_DATA structure.
+
+Before registering the lowpan netdev interface you must run:
+
+ lowpan_netdev_setup(dev, LOWPAN_LLTYPE_FOOBAR);
+
+wheres LOWPAN_LLTYPE_FOOBAR is a define for your 6LoWPAN linklayer type of
+enum lowpan_lltypes.
+
+Example to evaluate the private usually you can do:
+
+static inline sturct lowpan_priv_foobar *
+lowpan_foobar_priv(struct net_device *dev)
+{
+	return (sturct lowpan_priv_foobar *)lowpan_priv(dev)->priv;
+}
+
+switch (dev->type) {
+case ARPHRD_6LOWPAN:
+	lowpan_priv = lowpan_priv(dev);
+	/* do great stuff which is ARPHRD_6LOWPAN related */
+	switch (lowpan_priv->lltype) {
+	case LOWPAN_LLTYPE_FOOBAR:
+		/* do 802.15.4 6LoWPAN handling here */
+		lowpan_foobar_priv(dev)->bar = foo;
+		break;
+	...
+	}
+	break;
+...
+}
+
+In case of generic 6lowpan branch ("net/6lowpan") you can remove the check
+on ARPHRD_6LOWPAN, because you can be sure that these function are called
+by ARPHRD_6LOWPAN interfaces.
+
diff --git a/MAINTAINERS b/MAINTAINERS
index 98ede02..5baa91c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -158,6 +158,7 @@ L:	linux-wpan@vger.kernel.org
 S:	Maintained
 F:	net/6lowpan/
 F:	include/net/6lowpan.h
+F:	Documentation/networking/6lowpan.txt
 
 6PACK NETWORK DRIVER FOR AX.25
 M:	Andreas Koensgen <ajk@comnets.uni-bremen.de>
-- 
2.5.0

Re: [PATCH bluetooth-next 0/4] 6lowpan: introduce generic 6lowpan private data

[Marcel Holtmann]

Hi Alex,

> I already thought many times to introduce something like that. Here is a draft
> for introducing the generic 6lowpan private data into each lowpan interface.
> For the beginning I introduced the enum "lltype" which contains the LL type of
> a lowpan interface.
> 
> Use cases for such feature (LL types):
> 
> - If we do in upper layers (6LoWPAN/IPv6) a evaluation of dev->type then
>   the value is on all lowpan interfaces "APRHRD_6LOWPAN". If we checked on
>   "dev->type" and it's ARPHRD_6LOWPAN we can safe use lowpan_priv to get
>   6LoWPAN generic private data. With this data we can check the LL type which
>   can be currently BTLE or IEEE802154. This could be useful to make different
>   handling in iphc compress/decompress and evaluating LL private data of skb
>   control block "skb->cb".
> 
>   Example (802.15.4 has different address handling functionality):
> 
>   switch (lowpan_priv(dev)->lltype) {
>   case LOWPAN_LLTYPE_BTLE:
>        /* do EUI64 btle handling */
>        break;
>   case LOWPAN_LLTYPE_IEEE802154:
>        /* do complicated short/extended address handling */
>        /* we can surely call skb->cb to some other private data from LL
>           which was set before iphc compress/decompress function call */
>        break;
>   }
> 
>   The handling is currently for 802.15.4 is in generic 6lowpan code currently
>   not quite. This should be handled by private data. At the moment btle use
>   the same handling like for 802.15.4 extended address. Nevertheless is we can
>   cleanup some handling then in generic iphc functionality.
> 
>   This also possible in layers like IPv6, just doing a check on APRHRD_6LOWPAN
>   before calling lowpan_priv(dev)->lltype, then we are sure that the private
>   data of the interface is a 6LoWPAN interface and we can cast it to lowpan_priv.
>   Then we can do 6LoWPAN generic stuff OR 6lowpan specific LL stuff.
> 
> - In Lukasz Duda RFC for introducing stateful address compression, I saw
>   some behaviour which such functionality is also useful. Currently we don't
>   have a allocated space for a 6LoWPAN generic space which is assigned to a
>   lowpan interface. When LL layers (BTLE, IEEE802154) calls iphc
>   compress/decompress Lukasz had no change to access some room which is needed
>   for storing the context information into a table. The workaround for this
>   feature was to add allocate a static data room for the table and doing a
>   lookup/match of netdev name. Which a generic 6lowpan private data room per each
>   lowpan interface we can put this table according to the netdev private room,
>   which means in short: no lookup is needed anymore, just dereferencing lowpan_priv.
> 
>   In upper layer like IPv6 Lukasz could use that to get the stateful context
>   table information as an example for doing 6LoWPAN generic stuff in upper
>   layers.
> 
> 
> Note about the implementation for LL 6LoWPAN private pointer:
> 
> I stole some mechanism from wireless for that. See [0], the vif struct is part
> of sdata which is also part of private data of a wireless interface (mac80211).
> I hope I can just adapt this behaviour.
> 
> - Alex
> 
> Cc: Jonathan Corbet <corbet@lwn.net>
> Cc: linux-doc@vger.kernel.org
> 
> [0] http://lxr.free-electrons.com/source/include/net/mac80211.h#L1366
> 
> changes since PATCH (was RFC before):
> - rename ll_type,ll_foo to lltype, llfoo
> - add documentation for generic 6lowpan interfaces API
> - add net/6lowpan/core.c for core functionality, like setup or cleanup
>   lowpan netdev interfaces, which is necessary e.g. heap allocation/free
> - add LOWPAN_PRIV_SIZE for provide API functionality to calculate
>   private data
> - rebase to current bluetooth-next/master
> - add documentation in cc for the Documentation branch
> 
> changes since v2:
> - rename L2/l2 to LL/ll. I think the usually word in ietf for L2 is
>   LL which means "link layer". Also ipv6 stack use ll for variables like
>   lladdr -> link layer address.
> - rebase to current bluetooth-next/master
> - remove some brackets in function lowpan_priv.
> 
> Alexander Aring (4):
>  Bluetooth: 6lowpan: change netdev_priv to lowpan_dev
>  6lowpan: add generic 6lowpan netdev private data
>  6lowpan: move module_init into core functionality
>  documentation: networking: add 6lowpan documentation
> 
> Documentation/networking/6lowpan.txt | 51 ++++++++++++++++++++++++++++++++++++
> MAINTAINERS                          |  1 +
> include/net/6lowpan.h                | 23 ++++++++++++++++
> net/6lowpan/Makefile                 |  2 +-
> net/6lowpan/core.c                   | 40 ++++++++++++++++++++++++++++
> net/6lowpan/iphc.c                   | 19 --------------
> net/bluetooth/6lowpan.c              | 11 +++++---
> net/ieee802154/6lowpan/6lowpan_i.h   |  3 ++-
> net/ieee802154/6lowpan/core.c        |  4 ++-
> 9 files changed, 128 insertions(+), 26 deletions(-)
> create mode 100644 Documentation/networking/6lowpan.txt
> create mode 100644 net/6lowpan/core.c

I went ahead and applied all 4 patches to bluetooth-next tree. That way they get exposure.

Regards

Marcel