Commit graph

353 commits

Author SHA1 Message Date
Luis Carlos Cobo cfa22c716f mac80211: always force mesh_path deletions
Postponing the deletion is not really useful anymore.

Signed-off-by: Luis Carlos Cobo <luisca@cozybit.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 16:40:51 -05:00
Luis Carlos Cobo 89a1ad6990 mac80211: delete mesh_path timer on mesh_path removal
This avoids dereferencing a no longer existing struct mesh_path.

Signed-off-by: Luis Carlos Cobo <luisca@cozybit.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 16:40:51 -05:00
Luis Carlos Cobo aa2b592843 mac80211: clean up use of endianness conversion functions
Signed-off-by: Luis Carlos Cobo <luisca@cozybit.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 16:40:50 -05:00
Luis Carlos Cobo 4f5d4c4da8 mac80211: breakdown mesh network attributes in different extra fields for wext
Signed-off-by: Luis Carlos Cobo <luisca@cozybit.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 16:40:50 -05:00
Luis Carlos Cobo 3b091cd494 mac80211: move comment to better location
Signed-off-by: Luis Carlos Cobo <luisca@cozybit.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 16:40:49 -05:00
Luis Carlos Cobo 1d1b535969 mac80211: fix incorrect parenthesis
Pointed out by Johannes Berg.

Signed-off-by: Luis Carlos Cobo <luisca@cozybit.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 16:40:49 -05:00
Luis Carlos Cobo 37659ff8e1 mac80211: fix mesh endianness sparse warnings and unmark it as broken
This patch fixes all the mesh related endianness warnings reported by sparse. As
they were the reason why Johannes marked mesh as BROKEN, that flag has been
removed.

Signed-off-by: Luis Carlos Cobo <luisca@cozybit.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 16:40:48 -05:00
Johannes Berg 96c46546e2 mac80211: always insert key into list
Today I hit one of my new WARN_ONs in the mac80211 code because
a key wasn't being freed correctly. After wondering for a while
I finally tracked it to the fact that STA keys aren't added to
the per-sdata key list correctly, they are supposed to always be
on that list, not just for default keys. This patch fixes that.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:47 -05:00
Johannes Berg 03e4497ebe mac80211: fix sta_info mesh timer bug
I noticed a bug I introduced when mesh is enabled: sta_info_destroy()
will end up calling cancel_timer() on a timer that has never been
initialized because the timer is only initialized in mesh_plink_alloc(),
not in sta_info_alloc(). This patch moves the initialization of all mesh
related fields into sta_info_alloc(), adds a bit of sanity checking to
the cfg80211 handlers and sta_info_insert() and makes mesh_plink_alloc()
a static helper function that is only used from the mesh plink code.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Luis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:47 -05:00
Johannes Berg dbbea6713d mac80211: add documentation book
Quite a while ago I started this book. The required kernel-doc
patches have since gone into the tree so it is now possible to
build the book in mainline.

The actual documentation is still rather incomplete and not all
things are linked into the book, but this enables us to edit
the documentation collaboratively, hopefully driver authors can
add documentation based on their experience with mac80211.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:47 -05:00
Johannes Berg 7c8076bd8b mac80211: don't clear next_hop in path reclaim
Luis pointed out that this path is going to be freed right
away anyway so there's no point in assigning next_hop.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Luis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:47 -05:00
Johannes Berg 44213b5e13 mac80211: remove STA entries when taking down interface
When we take down an interface, we need to remove the STA info
items that belong to it because otherwise we might invoke a
sta_notify() callback in the driver when we later delete the
STA entries, but in that case the driver will already have
removed its knowledge of the interface they belonged to leading
to confusion. Also, we could invoke the set_tim() callback after
the driver removed its knowledge of the interface, which can
lead to a crash if it requests a beacon with a then-invalid vif
pointer!

A side effect of this patch is that, because it was easier, it
disallows changing the WDS peer while an interface is up. Should
that actually be necessary, it can be added back, but the WDS
peer STA entry may not be added while the interface is UP so for
now I've simplified the WDS peer's STA entry lifetime management.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:47 -05:00
Johannes Berg 693b1bbcc4 mac80211: clean up sta_info and document locking
This patch cleans up the sta_info struct and documents how
each set of variables is locked. Notably, flags locking is
completely missing. It also adds kernel-doc for some (but
not all yet) members of the struct.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:47 -05:00
Johannes Berg 73651ee639 mac80211: split sta_info_add
sta_info_add() has two functions: allocating a station info
structure and inserting it into the hash table/list. Splitting
these two functions allows allocating with GFP_KERNEL in many
places instead of GFP_ATOMIC which is now required by the RCU
protection. Additionally, in many places RCU protection is now
no longer needed at all because between sta_info_alloc() and
sta_info_insert() the caller owns the structure.

This fixes a few race conditions with setting initial flags
and similar, but not all (see comments in ieee80211_sta.c and
cfg.c). More documentation on the existing races will be in
a follow-up patch.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:47 -05:00
Johannes Berg d0709a6518 mac80211: RCU-ify STA info structure access
This makes access to the STA hash table/list use RCU to protect
against freeing of items. However, it's not a true RCU, the
copy step is missing: whenever somebody changes a STA item it
is simply updated. This is an existing race condition that is
now somewhat understandable.

This patch also fixes the race key freeing vs. STA destruction
by making sure that sta_info_destroy() is always called under
RTNL and frees the key.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:46 -05:00
Johannes Berg 5cf121c3cd mac80211: split ieee80211_txrx_data
Split it into ieee80211_tx_data and ieee80211_rx_data to clarify
usage/flag usage and remove the stupid union thing.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:46 -05:00
Johannes Berg 7495883bdd mac80211: reorder a few fields in sta_info
Three __le16s followed by an enum (int) leave a two-byte hole
of padding which we can use for two of the other fields.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:46 -05:00
Johannes Berg 42096b634f mac80211: fix kernel-doc comment for mesh_plink_deactivate
Accidentally copied in a __mesh_plink_deactivate, noticed by Luis
Carlos Cobo.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:46 -05:00
Johannes Berg d6d1a5a709 mac80211: clean up mesh RX path a bit more
Moves another ifdef into the sta_info header file in favour of
compiling more code even w/o CONFIG_MAC80211_MESH.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Luis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:46 -05:00
Johannes Berg c1edd987a4 mac80211: export mesh_plink_broken
This needs to be exported because rate control algorithms
can be modular.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:45 -05:00
Johannes Berg 5c142e8db4 mac80211: clarify mesh Kconfig
This clarifies that the mesh networking code is currently
based on Draft 1.08 of the 802.11 Mesh Networking amendment.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:44 -05:00
Johannes Berg ff59dc76e6 mac80211: add missing "break" statement in mesh code
This inserts a missing break statement which, if hit, would cause
the code to fall-through and unlock a spinlock twice. Noticed via
sparse's "lock count wrong in basic block" warning and careful
code inspection.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Luis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:43 -05:00
Johannes Berg 2f5ce793c0 mac80211: enable mesh in Kconfig
Currently marked BROKEN because of endianness problems.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:43 -05:00
Johannes Berg dc0b0f7d1e mac80211: mesh hwmp locking fixes
This fixes missing unlocks noticed by sparse.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:42 -05:00
Johannes Berg 902acc7896 mac80211: clean up mesh code
Various cleanups, reducing the #ifdef mess and other things.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:42 -05:00
Luis Carlos Cobo f7a9214437 mac80211: complete the mesh (interface handling) code
This completes the mesh interface handling code and a few other
bits about the mac80211 module.

Signed-off-by: Luis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:42 -05:00
Luis Carlos Cobo c5dd9c2bd0 mac80211: mesh path and mesh peer configuration
This adds code to allow adding mesh interfaces and configuring
mesh peers etc. Also, it adds code for station dumping.

Signed-off-by: Luis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:42 -05:00
Luis Carlos Cobo 9f42f60705 mac80211: mesh statistics and config through debugfs
This patch contains the debugfs code for mesh statistics and configuration
parameters. Please note that generic support for r/w debugfs attributes has been
added.

Signed-off-by: Luis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:42 -05:00
Luis Carlos Cobo 050ac52cbe mac80211: code for on-demand Hybrid Wireless Mesh Protocol
This file implements the on-demand Hybrid Wireless Mesh Protocol, at this moment
using hop-count as the metric. When no mesh path exists for a given destination
or the mesh path is not active, frames addressed to that destination will be
queued and a Path Request frame will be sent. Queued frames will be sent when
the path is resolved (usually after reception of a Path Response) or discarded
if discovery times out. Path Requests will also be sent to refresh paths that
are being used and are close to expiring.

Path Errors are sent when a path discovery process triggered by the attempt to
forward a frame originated in a different mesh point times out. Path Errors are
also sent when a peer link is determined to be unreachable because of high error
rates.

Multiple destination support in Path Requests and Path Errors and precursors
have not been implemented yet.

Signed-off-by: Luis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:42 -05:00
Luis Carlos Cobo eb2b9311fd mac80211: mesh path table implementation
The mesh path table associates destinations with the next hop to reach them. The
table is a hash of linked lists protected by rcu mechanisms. Every mesh path
contains a lock to protect the mesh path state.

Each outgoing mesh frame requires a look up into this table. Therefore, the
table it has been designed so it is not necessary to hold any lock to find the
appropriate next hop.

If the path is determined to be active within a rcu context we can safely
dereference mpath->next_hop->addr, since it holds a reference to the sta
next_hop. After a mesh path has been set active for the first time it next_hop
must always point to a valid sta.  If this is not possible the mpath must be
deleted or replaced in a RCU safe fashion.

Signed-off-by: Luis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:42 -05:00
Luis Carlos Cobo c3896d2ca4 mac80211: mesh peer link implementation
This file implements mesh discovery and peer link establishment support using
the mesh peer link table provided in mesh_plinktbl.c.

Secure peer links have not been implemented yet.

Signed-off-by: Luis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:41 -05:00
Luis Carlos Cobo f709fc696d mac80211: mesh changes to the MLME
This includes support for mesh network scanning. The ugly code in
ieee80211_sta_scan_result() is my approach to work around wext. This has been
tested with wireless tools version 29 and works as expected (the new interface
mode is just not shown).

Signed-off-by: Luis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:41 -05:00
Luis Carlos Cobo ee3858551a mac80211: mesh data structures and first mesh changes
Includes integration in struct sta_info of mesh peer link elements, previously
on their own mesh peer link table.

Signed-off-by: Luis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:41 -05:00
Luis Carlos Cobo 33b64eb2b1 mac80211: support for mesh interfaces in mac80211 data path
This changes the TX/RX paths in mac80211 to support mesh interfaces.
This code will be cleaned up later again before being enabled.

Signed-off-by: Luis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:41 -05:00
Luis Carlos Cobo 2e3c873682 mac80211: support functions for mesh
The two important features coded in mesh.c are:

Recently Multicast Cache: in on-demand HWMP, multicast traffic is retransmitted
by every receiving node. Even though a mesh TTL counter avoids infinite loops,
it is also necessary to avoid traffic explosion by keeping a cache of multicast
mesh frame that have been received recently. With this feature, maximum number
of retransmissions of a multicast frame for the case of N nodes within the range
of each other would be N. Without it, the maximum number of retransmissions
would be in the order of N^(MESH_TTL - 1).

Code to support mesh tables.

Signed-off-by: Luis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:41 -05:00
Luis Carlos Cobo ccf80ddfe4 mac80211: mesh function and data structures definitions
Signed-off-by: Luis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:41 -05:00
Johannes Berg 6032f934c8 mac80211: add mesh interface type
This adds the mesh interface type.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:41 -05:00
Luis Carlos Cobo 2ec600d672 nl80211/cfg80211: support for mesh, sta dumping
Added support for mesh id and mesh path operation as well as
station structure dumping.

Signed-off-by: Luis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-03-06 15:30:41 -05:00
Harvey Harrison 0dc47877a3 net: replace remaining __FUNCTION__ occurrences
__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-05 20:47:47 -08:00
Johannes Berg e486182907 mac80211: fix key replacing, hw accel
Even though I thought about it a lot and had also tested it, some
of my recent changes in the key code broke replacing keys, making
the kernel oops because a key is removed from a list while not on
it.

This patch fixes that using the list as an indication whether or
not the key is on it (an empty list means it's not on any list.)

Also, this patch fixes hw accel enabling, the check for not doing
hw accel when the interface is down was lost and is restored by
this.

Additionally, move adding the key to the list into the function
__ieee80211_key_replace() for more consistency.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-02-29 15:42:07 -05:00
Johannes Berg db4d1169d0 mac80211: split ieee80211_key_alloc/free
In order to RCU-ify sta_info, we need to be able to allocate
a key without linking it to an sdata/sta structure (because
allocation cannot be done in an rcu critical section). This
patch splits up ieee80211_key_alloc() and updates all users
appropriately.

While at it, this patch fixes a number of race conditions
such as finally making key replacement atomic, unfortunately
at the expense of more complex code.

Note that this patch documents /existing/ bugs with sta info
and key interaction, there is currently a race condition
when a sta info is freed without holding the RTNL. This will
finally be fixed by a followup patch.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-02-29 15:42:04 -05:00
Johannes Berg 6f48422a29 mac80211: remove STA infos last_ack stuff
These things aren't used and the only possible use is within
rate control algorithms, however those can, if they need it,
keep track of it in their private data. last_ack_ms isn't
even updated so completely useless.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-02-29 15:42:02 -05:00
Johannes Berg e6a5ddf208 mac80211: safely free beacon in ieee80211_if_reinit
If ieee80211_if_reinit() is called from ieee80211_unregister_hw()
then it is possible that the driver will still request a beacon
(it is allowed to until ieee80211_unregister_hw() has returned.)
This means we need to use an RCU-protected write to the beacon
information even in this function.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-02-29 15:42:00 -05:00
Johannes Berg fba4a1e637 mac80211: fix IBSS code
This patch fixes two errors introduced by

    commit 19d35612f3cd7f60dd9174c0100584e21f5a1025
    Author: Bruno Randolf <bruno@thinktube.com>
    Date:   Mon Feb 18 11:21:36 2008 +0900

        mac80211: enable IBSS merging

The first error is an endianness problem that sparse found and
the second is a build failure when CONFIG_MAC80211_IBSS_DEBUG
is not set.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Bruno Randolf <bruno@thinktube.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-02-29 15:41:41 -05:00
Johannes Berg f3af89d1aa mac80211: fix debugfs_sta print_mac() warning
When print_mac() was marked as __pure to avoid emitting a function
call in pr_debug() scenarios, a warning in this code surfaced since
it relies on the fact that the buffer is modified and doesn't use
the return value. This patch makes it use the return value instead.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Reported-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-02-29 15:41:38 -05:00
Johannes Berg 665e8aafb4 mac80211: Disallow concurrent IBSS/STA mode interfaces
Disallow having more than one IBSS interface up at any time
because of beacon distribution issues, and for now also disallow
having more than one IBSS/STA interface up at the same time
because we use the master interface's BSS struct which would
be completely corrupted when we have more than one up.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-02-29 15:41:36 -05:00
Johannes Berg 43ba7e958f mac80211: atomically check whether STA exists already
When a STA structure is added, it is often checked whether it
already exists before adding it. This, however, isn't done
atomically so there is a race condition that could lead to two
STA structures being added with the same MAC address. This
patch changes sta_info_add() to return an ERR_PTR in case
of failure and adds the failure mode -EEXIST when the STA
already exists.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Luis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-02-29 15:41:34 -05:00
Johannes Berg d46e144b65 mac80211: rework TX filtered frame code
This reworks the code for TX filtered frames, splitting it out to
a new function to handle those cases, making the clear instruction
a flag and renaming a few things to be easier to understand and
less Atheros hardware specific. Finally, it also makes the comments
explain more.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-02-29 15:41:32 -05:00
Pavel Roskin d97cf01576 mac80211: fix incorrect use of CONFIG_MAC80211_IBSS_DEBUG
Configuration variables are only available to the preprocessor

Signed-off-by: Pavel Roskin <proski@gnu.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-02-29 15:37:27 -05:00
Johannes Berg 004c872e78 mac80211: consolidate TIM handling code
This consolidates all TIM handling code to avoid re-introducing
errors with the bitmap/set_tim order and to reduce code. While
reading the code I noticed a possible problem so I also added
a comment about that.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-02-29 15:37:26 -05:00