linux/drivers
Johannes Berg f444de05d2 cfg80211/mac80211: better channel handling
Currently (all tested with hwsim) you can do stupid
things like setting up an AP on a certain channel,
then adding another virtual interface and making
that associate on another channel -- this will make
the beaconing to move channel but obviously without
the necessary IEs data update.

In order to improve this situation, first make the
configuration APIs (cfg80211 and nl80211) aware of
multi-channel operation -- we'll eventually need
that in the future anyway. There's one userland API
change and one API addition. The API change is that
now SET_WIPHY must be called with virtual interface
index rather than only wiphy index in order to take
effect for that interface -- luckily all current
users (hostapd) do that. For monitor interfaces, the
old setting is preserved, but monitors are always
slaved to other devices anyway so no guarantees.

The second userland API change is the introduction
of a per virtual interface SET_CHANNEL command, that
hostapd should use going forward to make it easier
to understand what's going on (it can automatically
detect a kernel with this command).

Other than mac80211, no existing cfg80211 drivers
are affected by this change because they only allow
a single virtual interface.

mac80211, however, now needs to be aware that the
channel settings are per interface now, and needs
to disallow (for now) real multi-channel operation,
which is another important part of this patch.

One of the immediate benefits is that you can now
start hostapd to operate on a hardware that already
has a connection on another virtual interface, as
long as you specify the same channel.

Note that two things are left unhandled (this is an
improvement -- not a complete fix):

 * different HT/no-HT modes

   currently you could start an HT AP and then
   connect to a non-HT network on the same channel
   which would configure the hardware for no HT;
   that can be fixed fairly easily

 * CSA

   An AP we're connected to on a virtual interface
   might indicate switching channels, and in that
   case we would follow it, regardless of how many
   other interfaces are operating; this requires
   more effort to fix but is pretty rare after all

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-05-07 14:55:50 -04:00
..
accessibility
acpi Merge branch 'acpica' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2010-03-01 10:36:22 -08:00
amba
ata Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev 2010-03-01 13:04:58 -08:00
atm
auxdisplay
base PM: Allow device drivers to use dpm_wait() 2010-02-26 20:39:11 +01:00
block Merge branch 'for-2.6.34' of git://git.kernel.dk/linux-2.6-block 2010-03-01 09:00:29 -08:00
bluetooth Bluetooth: Convert Marvell driver to use per adapter debugfs 2010-02-27 14:05:38 +01:00
cdrom block: Consolidate phys_segment and hw_segment limits 2010-02-26 13:58:08 +01:00
char Merge branch 'omap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6 2010-03-02 10:34:25 -08:00
clocksource Merge branch 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-03-01 08:48:25 -08:00
connector connector: Delete buggy notification code. 2010-02-02 15:58:48 -08:00
cpufreq
cpuidle
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2010-02-26 16:50:02 -08:00
dca
dio
dma Merge branch 'sh/stable-updates' 2010-02-15 14:49:37 +09:00
edac Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp 2010-02-11 14:07:13 -08:00
eisa
firewire block: Rename blk_queue_max_sectors to blk_queue_max_hw_sectors 2010-02-26 13:58:08 +01:00
firmware Merge branch 'master' of /home/davem/src/GIT/linux-2.6/ 2010-02-28 19:23:06 -08:00
gpio
gpu Merge branch 'x86-pci-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-02-28 10:59:18 -08:00
hid Merge branches 'upstream', 'raw_report_modifications' and 'apple_magic_mouse' into for-linus 2010-02-25 17:39:16 +01:00
hwmon Merge commit 'origin/master' into next 2010-02-17 10:00:42 +11:00
i2c Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm 2010-03-01 09:15:15 -08:00
ide Merge branch 'acpica' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2010-03-01 10:36:22 -08:00
idle
ieee1394 block: Rename blk_queue_max_sectors to blk_queue_max_hw_sectors 2010-02-26 13:58:08 +01:00
ieee802154
infiniband ipoib: returned back addrlen check for mc addresses 2010-02-28 01:34:28 -08:00
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2010-03-01 10:38:09 -08:00
isdn Merge branch 'master' of /home/davem/src/GIT/linux-2.6/ 2010-02-28 19:23:06 -08:00
leds
lguest
macintosh Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2010-03-01 10:38:09 -08:00
mca
md block: Consolidate phys_segment and hw_segment limits 2010-02-26 13:58:08 +01:00
media Merge branch 'master' of /home/davem/src/GIT/linux-2.6/ 2010-02-28 19:23:06 -08:00
memstick block: Consolidate phys_segment and hw_segment limits 2010-02-26 13:58:08 +01:00
message Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6 2010-03-02 07:55:08 -08:00
mfd Merge with mainline to remove plat-omap/Kconfig conflict 2010-03-01 14:19:05 -08:00
misc
mmc Merge with mainline to remove plat-omap/Kconfig conflict 2010-03-01 14:19:05 -08:00
mtd Merge with mainline to remove plat-omap/Kconfig conflict 2010-03-01 14:19:05 -08:00
net cfg80211/mac80211: better channel handling 2010-05-07 14:55:50 -04:00
nubus
of of: move definition of of_chosen into common code. 2010-02-14 07:13:55 -07:00
oprofile
parisc
parport
pci Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6 2010-03-02 07:55:08 -08:00
pcmcia Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus 2010-02-27 16:19:22 -08:00
platform Merge branch 'acpica' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2010-03-01 10:36:22 -08:00
pnp
power wm97xx_battery: Handle missing platform data gracefully 2010-01-29 17:00:18 +03:00
pps
ps3 powerpc: Remove trailing space in messages 2010-02-09 13:56:23 +11:00
rapidio
regulator regulator/lp3971: vol_map out of bounds in lp3971_{ldo,dcdc}_set_voltage() 2010-02-12 11:39:49 +00:00
rtc Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm 2010-03-01 09:15:15 -08:00
s390 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6 2010-03-02 07:55:08 -08:00
sbus Merge commit 'v2.6.33-rc5' into secretlab/test-devicetree 2010-01-28 14:38:25 -07:00
scsi Merge branch 'for-2.6.34' of git://git.kernel.dk/linux-2.6-block 2010-03-01 09:00:29 -08:00
serial Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm 2010-03-01 09:15:15 -08:00
sfi
sh sh: Use dummy_irq_chip for INTC redirect vectors. 2010-02-17 12:37:42 +09:00
sn
spi Merge with mainline to remove plat-omap/Kconfig conflict 2010-03-01 14:19:05 -08:00
ssb ssb: Make bus registration failure not be silent 2010-04-26 14:21:23 -04:00
staging Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6 2010-03-02 07:55:08 -08:00
tc
telephony
thermal
uio
usb Merge with mainline to remove plat-omap/Kconfig conflict 2010-03-01 14:19:05 -08:00
uwb
vhost vhost-net: restart tx poll on sk_sndbuf full 2010-02-28 19:50:33 +02:00
video Merge branch 'for-linus' of git://gitorious.org/linux-omap-dss2/linux 2010-03-02 10:41:26 -08:00
virtio virtio: fix out of range array access 2010-02-28 20:39:11 +02:00
vlynq
w1 omap3: Replace ARCH_OMAP34XX with ARCH_OMAP3 2010-02-15 09:27:02 -08:00
watchdog Merge with mainline to remove plat-omap/Kconfig conflict 2010-03-01 14:19:05 -08:00
xen
zorro
Kconfig
Makefile