linux-toradex.git/drivers/s390/net/Kconfig, branch master

dibs: Move event handling to dibs layer

2025-09-23T09:13:22+00:00

Add defines for all event types and subtypes an ism device is known to
produce as it can be helpful for debugging purposes.

Introduces a generic 'struct dibs_event' and adopt ism device driver
and smc-d client accordingly. Tolerate and ignore other type and subtype
values to enable future device extensions.

SMC-D and ISM are now independent.
struct ism_dev can be moved to drivers/s390/net/ism.h.

Note that in smc, the term 'ism' is still used. Future patches could
replace that with 'dibs' or 'smc-d' as appropriate.

Signed-off-by: Julian Ruess 
Co-developed-by: Alexandra Winter 
Signed-off-by: Alexandra Winter 
Link: https://patch.msgid.link/20250918110500.1731261-15-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni

dibs: Register ism as dibs device

2025-09-23T09:13:21+00:00

Register ism devices with the dibs layer. Follow-on patches will move
functionality to the dibs layer.

As DIBS is only a shim layer without any dependencies, we can depend ISM
on DIBS without adding indirect dependencies. A follow-on patch will
remove implication of SMC by ISM.

Define struct dibs_dev. Follow-on patches will move more content into
dibs_dev.  The goal of follow-on patches is that ism_dev will only
contain fields that are special for this device driver. The same concept
will apply to other dibs device drivers.

Define dibs_dev_alloc(), dibs_dev_add() and dibs_dev_del() to be called
by dibs device drivers and call them from ism_drv.c
Use ism_dev.dibs for a pointer to dibs_dev.

Signed-off-by: Alexandra Winter 
Link: https://patch.msgid.link/20250918110500.1731261-6-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni

s390/net: Remove NETIUCV device driver

2025-07-17T00:53:40+00:00

The netiucv driver creates TCP/IP interfaces over IUCV between Linux
guests on z/VM and other z/VM entities.

Rationale for removal:
- NETIUCV connections are only supported for compatibility with
  earlier versions and not to be used for new network setups,
  since at least Linux kernel 4.0.
- No known active users, use cases, or product dependencies
- The driver is no longer relevant for z/VM networking;
  preferred methods include:
	* Device pass-through (e.g., OSA, RoCE)
	* z/VM Virtual Switch (VSWITCH)

The IUCV mechanism itself remains supported and is actively used
via AF_IUCV, hvc_iucv, and smsg_iucv.

Signed-off-by: Nagamani PV 
Reviewed-by: Alexandra Winter 
Signed-off-by: Alexandra Winter 
Reviewed-by: Simon Horman 
Link: https://patch.msgid.link/20250715074210.3999296-1-wintera@linux.ibm.com
Signed-off-by: Jakub Kicinski

s390/net: Remove LCS driver

2025-02-06T02:19:01+00:00

The original Open Systems Adapter (OSA) was introduced by IBM in the
mid-90s. These were then superseded by OSA-Express in 1999 which used
Queued Direct IO to greatly improve throughput. The newer cards
retained the older, slower non-QDIO (OSE) modes for compatibility with
older systems. In Linux, the lcs driver was responsible for cards
operating in the older OSE mode and the qeth driver was introduced to
allow the OSA-Express cards to operate in the newer QDIO (OSD) mode.

For an S390 machine from 1998 or later, there is no reason to use the
OSE mode and lcs driver as all OSA cards since 1999 provide the faster
OSD mode. As a result, it's been years since we have heard of a
customer configuration involving the lcs driver.

This patch removes the lcs driver. The technology it supports has been
obsolete for past 25+ years and is irrelevant for current use cases.

Reviewed-by: Alexandra Winter 
Acked-by: Heiko Carstens 
Acked-by: Peter Oberparleiter 
Signed-off-by: Aswin Karuvally 
Signed-off-by: Alexandra Winter 
Reviewed-by: Simon Horman 
Link: https://patch.msgid.link/20250204103135.1619097-1-wintera@linux.ibm.com
Signed-off-by: Jakub Kicinski

s390/ism: ism driver implies smc protocol

2023-11-17T00:31:00+00:00

Since commit a72178cfe855 ("net/smc: Fix dependency of SMC on ISM")
you can build the ism code without selecting the SMC network protocol.
That leaves some ism functions be reported as unused. Move these
functions under the conditional compile with CONFIG_SMC.

Also codify the suggestion to also configure the SMC protocol in ism's
Kconfig - but with an "imply" rather than a "select" as SMC depends on
other config options and allow for a deliberate decision not to build
SMC. Also, mention that in ISM's help.

Fixes: a72178cfe855 ("net/smc: Fix dependency of SMC on ISM")
Reported-by: Randy Dunlap 
Closes: https://lore.kernel.org/netdev/afd142a2-1fa0-46b9-8b2d-7652d41d3ab8@infradead.org/
Signed-off-by: Gerd Bayer 
Reviewed-by: Wenjia Zhang 
Reviewed-by: Simon Horman 
Acked-by: Randy Dunlap 
Tested-by: Randy Dunlap  # build-tested
Signed-off-by: David S. Miller

net/smc: Fix dependency of SMC on ISM

2023-10-10T09:51:41+00:00

When the SMC protocol is built into the kernel proper while ISM is
configured to be built as module, linking the kernel fails due to
unresolved dependencies out of net/smc/smc_ism.o to
ism_get_smcd_ops, ism_register_client, and ism_unregister_client
as reported via the linux-next test automation (see link).
This however is a bug introduced a while ago.

Correct the dependency list in ISM's and SMC's Kconfig to reflect the
dependencies that are actually inverted. With this you cannot build a
kernel with CONFIG_SMC=y and CONFIG_ISM=m. Either ISM needs to be 'y',
too - or a 'n'. That way, SMC can still be configured on non-s390
architectures that do not have (nor need) an ISM driver.

Fixes: 89e7d2ba61b7 ("net/ism: Add new API for client registration")
Reported-by: Randy Dunlap 
Closes: https://lore.kernel.org/linux-next/d53b5b50-d894-4df8-8969-fd39e63440ae@infradead.org/
Co-developed-by: Wenjia Zhang 
Signed-off-by: Wenjia Zhang 
Signed-off-by: Gerd Bayer 
Reviewed-by: Simon Horman 
Tested-by: Simon Horman  # build-tested
Acked-by: Randy Dunlap 
Tested-by: Randy Dunlap  # build-tested
Link: https://lore.kernel.org/r/20231006125847.1517840-1-gbayer@linux.ibm.com
Signed-off-by: Paolo Abeni

s390/lcs: Remove FDDI option

2023-07-26T03:06:56+00:00

The last s390 machine that supported FDDI was z900 ('7th generation',
released in 2000). The oldest machine generation currently supported by
the Linux kernel is MARCH_Z10 (released 2008). If there is still a usecase
for connecting a Linux on s390 instance to a LAN Channel Station (LCS), it
can only do so via Ethernet.

Randy Dunlap[1] found that LCS over FDDI has never worked, when FDDI
was compiled as module. Instead of fixing that, remove the FDDI option
from the lcs driver.

While at it, make the CONFIG_LCS description a bit more helpful.

References:
[1] https://lore.kernel.org/netdev/20230621213742.8245-1-rdunlap@infradead.org/

Signed-off-by: Alexandra Winter 
Acked-by: Christian Borntraeger 
Reviewed-by: Randy Dunlap 
Reviewed-by: Simon Horman 
Link: https://lore.kernel.org/r/20230724131546.3597001-1-wintera@linux.ibm.com
Signed-off-by: Jakub Kicinski

s390/qeth: Switchdev event handler

2021-08-07T08:44:02+00:00

QETH HiperSockets devices with LEARNING_SYNC capability can be used
to construct a linux bridge with:
2 isolated southbound interfaces:
     a) a default network interface
     b) a LEARNING-SYNC HiperSockets interface
and 1 non-isolated northbound interface. This is called a 'HiperSockets
Converged Interface' (HSCI).
The existing LEARNING_SYNC functionality is used to update the bridge fdb
with MAC addresses that should be sent-out via the HiperSockets interface,
instead of the default network interface.

Add handling of switchdev events SWITCHDEV_FDB_ADD_TO_DEVICE and
SWITCHDEV_FDB_DEL_TO_DEVICE to the qeth LEARNING_SYNC functionality. Thus
if the northbound bridgeport of an HSCI doesn't only have a single static
MAC address, but instead is a learning bridgeport, work is enqueued, so
the HiperSockets virtual switch (that is external to this Linux instance)
can update its fdb.

When BRIDGE is a loadable module, QETH_L2 mustn't be built-in:

drivers/s390/net/qeth_l2_main.o: in function 'qeth_l2_switchdev_event':
drivers/s390/net/qeth_l2_main.c:927: undefined reference to
'br_port_flag_is_set'

Add Kconfig dependency to enforce usable configurations.

Signed-off-by: Alexandra Winter 
Reviewed-by: Wenjia Zhang 
Signed-off-by: Karsten Graul 
Signed-off-by: David S. Miller

s390/qeth: remove OSN support

2021-07-20T13:17:06+00:00

Commit fb64de1bc36c ("s390/qeth: phase out OSN support") spelled out
why the OSN support in qeth is in a bad shape, and put any remaining
interested parties on notice to speak up before it gets ripped out.

It's 2021 now, so make true on that promise and remove all the
OSN-specific parts from qeth. This also means that we no longer need to
export various parts of the cmd & data path internals to the L2 driver.

Signed-off-by: Julian Wiedmann 
Reviewed-by: Alexandra Winter 
Signed-off-by: David S. Miller

s390/net: add SMC config as one of the defaults of CCWGROUP

2020-09-10T22:24:26+00:00

arch/s390/net/pnet.c uses ccwgroup function dev_is_ccwgroup()
in pnetid_by_dev_port().
For s390 the net/smc code makes use of function pnetid_by_dev_port().
Make sure ccwgroup is built into the kernel, if smc is to be built
into the kernel.

Signed-off-by: Guvenc Gulce 
Reviewed-by: Ursula Braun 
Signed-off-by: Karsten Graul 
Signed-off-by: David S. Miller