Linux kernel source tree
Go to file
Alexandra Winter 10a6cfc0fc s390/qeth: Translate address events into switchdev notifiers
A qeth-l2 HiperSockets card can show switch-ish behaviour in the sense,
that it can report all MACs that are reachable via this interface. Just
like a switch device, it can notify the software bridge about changes
to its fdb. This patch exploits this device-to-bridge-notification and
extracts the relevant information from the hardware events to generate
notifications to an attached software bridge.

There are 2 sources for this information:
1) The reply message of Perform-Network-Subchannel-Operations (PNSO)
(operation code ADDR_INFO) reports all addresses that are currently
reachable (implemented in a later patch).
2) As long as device-to-bridge-notification is enabled, hardware will
generate address change notification events, whenever the content of
the hardware fdb changes (this patch).

The bridge_hostnotify feature (PNSO operation code BRIDGE_INFO) uses
the same address change notification events. We need to distinguish
between qeth_pnso_mode QETH_PNSO_BRIDGEPORT and QETH_PNSO_ADDR_INFO
and call a different handler. In both cases deadlocks must be
prevented, if the workqueue is drained under lock and QETH_PNSO_NONE,
when notification is disabled.

bridge_hostnotify generates udev events, there is no intend to do the same
for dev2br. Instead this patch will generate SWITCHDEV_FDB_ADD_TO_BRIDGE
and SWITCHDEV_FDB_DEL_TO_BRIDGE notifications, that will cause the
software bridge to add (or delete) entries to its fdb as 'extern_learn
offload'.

Documentation/networking/switchdev.txt proposes to add
"depends NET_SWITCHDEV" to driver's Kconfig. This is not done here,
so even in absence of the NET_SWITCHDEV module, the QETH_L2 module will
still be built, but then the switchdev notifiers will have no effect.

No VLAN filtering is done on the entries and VLAN information is not
passed on to the bridge fdb entries. This could be added later.
For now VLAN interfaces can be defined on the upper bridge interface.

Multicast entries are not passed on to the bridge fdb.
This could be added later. For now mcast flooding can be used in the
bridge.

The card reports all MACs that are in its FDB, but we must not pass on
MACs that are registered for this interface.

Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-15 13:21:47 -07:00
arch s390/cio: Helper functions to read CSSID, IID, and CHID 2020-09-15 13:21:46 -07:00
block block-5.9-2020-09-04 2020-09-04 13:04:51 -07:00
certs .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2020-08-30 15:53:44 -07:00
Documentation dt-bindings: net: dsa: add new MT7531 binding to support MT7531 2020-09-14 16:30:39 -07:00
drivers s390/qeth: Translate address events into switchdev notifiers 2020-09-15 13:21:47 -07:00
fs Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-09-04 21:28:59 -07:00
include Merge branch '40GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/jkirsher/next-queue 2020-09-14 14:07:58 -07:00
init Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-09-04 21:28:59 -07:00
ipc treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
kernel Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-09-04 21:28:59 -07:00
lib Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-09-04 21:28:59 -07:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-09-04 21:28:59 -07:00
net tcp: schedule EPOLLOUT after a partial sendmsg 2020-09-14 16:58:24 -07:00
samples Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-09-04 21:28:59 -07:00
scripts Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-09-04 21:28:59 -07:00
security Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-09-04 21:28:59 -07:00
sound sound fixes for 5.9-rc4 2020-09-04 12:05:25 -07:00
tools mptcp: simult flow self-tests 2020-09-14 13:28:03 -07:00
usr Merge branch 'work.fdpic' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 13:29:39 -07:00
virt * PAE and PKU bugfixes for x86 2020-08-22 10:03:05 -07:00
.clang-format block: add bio_for_each_bvec_all() 2020-05-25 11:25:24 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: Add ZSTD-compressed files 2020-07-31 11:50:49 +02:00
.mailmap Merge branch 'akpm' (patches from Andrew) 2020-08-21 14:44:48 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Add Krzysztof Kozlowski to Samsung S3FWRN5 and remove Robert 2020-09-10 15:22:16 -07:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS MAINTAINERS: Add Krzysztof Kozlowski to Samsung S3FWRN5 and remove Robert 2020-09-10 15:22:16 -07:00
Makefile Linux 5.9-rc3 2020-08-30 16:01:54 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.