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 <julianr@linux.ibm.com>
Co-developed-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://patch.msgid.link/20250918110500.1731261-15-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Use struct dibs_dmb instead of struct smc_dmb and move the corresponding
client tables to dibs_dev. Leave driver specific implementation details
like sba in the device drivers.
Register and unregister dmbs via dibs_dev_ops. A dmb is dedicated to a
single client, but a dibs device can have dmbs for more than one client.
Trigger dibs clients via dibs_client_ops->handle_irq(), when data is
received into a dmb. For dibs_loopback replace scheduling an smcd receive
tasklet with calling dibs_client_ops->handle_irq().
For loopback devices attach_dmb(), detach_dmb() and move_data() need to
access the dmb tables, so move those to dibs_dev_ops in this patch as well.
Remove remaining definitions of smc_loopback as they are no longer
required, now that everything is in dibs_loopback.
Note that struct ism_client and struct ism_dev are still required in smc
until a follow-on patch moves event handling to dibs. (Loopback does not
use events).
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://patch.msgid.link/20250918110500.1731261-14-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Provide the dibs_dev_ops->query_remote_gid() in ism and dibs_loopback
dibs_devices. And call it in smc dibs_client.
Reviewed-by: Julian Ruess <julianr@linux.ibm.com>
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://patch.msgid.link/20250918110500.1731261-13-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
It can be debated how much benefit definition of vlan ids for dibs devices
brings, as the dmbs are accessible only by a single peer anyhow. But ism
provides vlan support and smcd exploits it, so move it to dibs layer as an
optional feature.
smcd_loopback simply ignores all vlan settings, do the same in
dibs_loopback.
SMC-D and ISM have a method to use the invalid VLAN ID 1FFF
(ISM_RESERVED_VLANID), to indicate that both communication peers support
routable SMC-Dv2. Tolerate it in dibs, but move it to SMC only.
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://patch.msgid.link/20250918110500.1731261-12-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Define a uuid_t GID attribute to identify a dibs device.
SMC uses 64 Bit and 128 Bit Global Identifiers (GIDs) per device, that
need to be sent via the SMC protocol. Because the smc code uses integers,
network endianness and host endianness need to be considered. Avoid this
in the dibs layer by using uuid_t byte arrays. Future patches could change
SMC to use uuid_t. For now conversion helper functions are introduced.
ISM devices provide 64 Bit GIDs. Map them to dibs uuid_t GIDs like this:
_________________________________________
| 64 Bit ISM-vPCI GID | 00000000_00000000 |
-----------------------------------------
If interpreted as UUID [1], this would be interpreted as the UIID variant,
that is reserved for NCS backward compatibility. So it will not collide
with UUIDs that were generated according to the standard.
smc_loopback already uses version 4 UUIDs as 128 Bit GIDs, move that to
dibs loopback. A temporary change to smc_lo_query_rgid() is required,
that will be moved to dibs_loopback with a follow-on patch.
Provide gid of a dibs device as sysfs read-only attribute.
Link: https://datatracker.ietf.org/doc/html/rfc4122 [1]
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Julian Ruess <julianr@linux.ibm.com>
Reviewed-by: Mahanta Jambigi <mjambigi@linux.ibm.com>
Link: https://patch.msgid.link/20250918110500.1731261-11-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Move struct device from ism_dev and smc_lo_dev to dibs_dev, and define a
corresponding release function. Free ism_dev in ism_remove() and smc_lo_dev
in smc_lo_dev_remove().
Replace smcd->ops->get_dev(smcd) by using dibs->dev directly.
An alternative design would be to embed dibs_dev as a field in ism_dev and
do the same for other dibs device driver specific structs. However that
would have the disadvantage that each dibs device driver needs to allocate
dibs_dev and each dibs device driver needs a different device release
function. The advantage would be that ism_dev and other device driver
specific structs would be covered by device reference counts.
Signed-off-by: Julian Ruess <julianr@linux.ibm.com>
Co-developed-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Mahanta Jambigi <mjambigi@linux.ibm.com>
Link: https://patch.msgid.link/20250918110500.1731261-9-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Move the device add() and remove() functions from ism_client to
dibs_client_ops and call add_dev()/del_dev() for ism devices and
dibs_loopback devices. dibs_client_ops->add_dev() = smcd_register_dev() for
the smc_dibs_client. This is the first step to handle ism and loopback
devices alike (as dibs devices) in the smc dibs client.
Define dibs_dev->ops and move smcd_ops->get_chid to
dibs_dev_ops->get_fabric_id() for ism and loopback devices. See below for
why this needs to be in the same patch as dibs_client_ops->add_dev().
The following changes contain intermediate steps, that will be obsoleted by
follow-on patches, once more functionality has been moved to dibs:
Use different smcd_ops and max_dmbs for ism and loopback. Follow-on patches
will change SMC-D to directly use dibs_ops instead of smcd_ops.
In smcd_register_dev() it is now necessary to identify a dibs_loopback
device before smcd_dev and smcd_ops->get_chid() are available. So provide
dibs_dev_ops->get_fabric_id() in this patch and evaluate it in
smc_ism_is_loopback().
Call smc_loopback_init() in smcd_register_dev() and call
smc_loopback_exit() in smcd_unregister_dev() to handle the functionality
that is still in smc_loopback. Follow-on patches will move all smc_loopback
code to dibs_loopback.
In smcd_[un]register_dev() use only ism device name, this will be replaced
by dibs device name by a follow-on patch.
End of changes with intermediate parts.
Allocate an smcd event workqueue for all dibs devices, although
dibs_loopback does not generate events.
Use kernel memory instead of devres memory for smcd_dev and smcd->conn.
Since commit a72178cfe8 ("net/smc: Fix dependency of SMC on ISM") an ism
device and its driver can have a longer lifetime than the smc module, so
smc should not rely on devres to free its resources [1]. It is now the
responsibility of the smc client to free smcd and smcd->conn for all dibs
devices, ism devices as well as loopback. Call client->ops->del_dev() for
all existing dibs devices in dibs_unregister_client(), so all device
related structures can be freed in the client.
When dibs_unregister_client() is called in the context of smc_exit() or
smc_core_reboot_event(), these functions have already called
smc_lgrs_shutdown() which calls smc_smcd_terminate_all(smcd) and sets
going_away. This is done a second time in smcd_unregister_dev(). This is
analogous to how smcr is handled in these functions, by calling first
smc_lgrs_shutdown() and then smc_ib_unregister_client() >
smc_ib_remove_dev(), so leave it that way. It may be worth investigating,
whether smc_lgrs_shutdown() is still required or useful.
Remove CONFIG_SMC_LO. CONFIG_DIBS_LO now controls whether a dibs loopback
device exists or not.
Link: https://www.kernel.org/doc/Documentation/driver-model/devres.txt [1]
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Mahanta Jambigi <mjambigi@linux.ibm.com>
Link: https://patch.msgid.link/20250918110500.1731261-8-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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 <wintera@linux.ibm.com>
Link: https://patch.msgid.link/20250918110500.1731261-6-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Formally register smc as dibs client. Functionality will be moved by
follow-on patches from ism_client to dibs_client until eventually
ism_client can be removed.
As DIBS is only a shim layer without any dependencies, we can depend SMC
on DIBS without adding indirect dependencies. A follow-on patch will
remove dependency of SMC on ISM.
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Julian Ruess <julianr@linux.ibm.com>
Link: https://patch.msgid.link/20250918110500.1731261-5-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Create the file structure for a 'DIBS - Direct Internal Buffer Sharing'
shim layer that will provide generic functionality and declarations for
dibs device drivers and dibs clients.
Following patches will add functionality.
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://patch.msgid.link/20250918110500.1731261-4-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Julian Ruess