kernel/linux.git/net/smc/Makefile, branch v6.18.22

dibs: Move data path to dibs layer

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

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 Link: https://patch.msgid.link/20250918110500.1731261-14-wintera@linux.ibm.com Signed-off-by: Paolo Abeni

dibs: Define dibs_client_ops and dibs_dev_ops

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

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 a72178cfe855 ("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 Reviewed-by: Mahanta Jambigi Link: https://patch.msgid.link/20250918110500.1731261-8-wintera@linux.ibm.com Signed-off-by: Paolo Abeni

net/smc: Introduce IPPROTO_SMC

2024-06-17T12:14:09+00:00

This patch allows to create smc socket via AF_INET, similar to the following code, /* create v4 smc sock */ v4 = socket(AF_INET, SOCK_STREAM, IPPROTO_SMC); /* create v6 smc sock */ v6 = socket(AF_INET6, SOCK_STREAM, IPPROTO_SMC); There are several reasons why we believe it is appropriate here: 1. For smc sockets, it actually use IPv4 (AF-INET) or IPv6 (AF-INET6) address. There is no AF_SMC address at all. 2. Create smc socket in the AF_INET(6) path, which allows us to reuse the infrastructure of AF_INET(6) path, such as common ebpf hooks. Otherwise, smc have to implement it again in AF_SMC path. Signed-off-by: D. Wythe Reviewed-by: Wenjia Zhang Reviewed-by: Dust Li Tested-by: Niklas Schnelle Tested-by: Wenjia Zhang Signed-off-by: David S. Miller

net/smc: introduce loopback-ism for SMC intra-OS shortcut

2024-04-30T11:24:48+00:00

This introduces a kind of Emulated-ISM device named loopback-ism for SMCv2.1. The loopback-ism device is currently exclusive for SMC usage, and aims to provide an SMC shortcut for sockets within the same kernel, leading to improved intra-OS traffic performance. Configuration of this feature is managed through the config SMC_LO. Signed-off-by: Wen Gu Reviewed-by: Gerd Bayer Reviewed-by: Wenjia Zhang Reviewed-and-tested-by: Jan Karcher Signed-off-by: Paolo Abeni

net/smc: fix compile warning for smc_sysctl

2022-03-07T11:59:17+00:00

kernel test robot reports multiple warning for smc_sysctl: In file included from net/smc/smc_sysctl.c:17: >> net/smc/smc_sysctl.h:23:5: warning: no previous prototype \ for function 'smc_sysctl_init' [-Wmissing-prototypes] int smc_sysctl_init(void) ^ and >> WARNING: modpost: vmlinux.o(.text+0x12ced2d): Section mismatch \ in reference from the function smc_sysctl_exit() to the variable .init.data:smc_sysctl_ops The function smc_sysctl_exit() references the variable __initdata smc_sysctl_ops. This is often because smc_sysctl_exit lacks a __initdata annotation or the annotation of smc_sysctl_ops is wrong. and net/smc/smc_sysctl.c: In function 'smc_sysctl_init_net': net/smc/smc_sysctl.c:47:17: error: 'struct netns_smc' has no member named 'smc_hdr' 47 | net->smc.smc_hdr = register_net_sysctl(net, "net/smc", table); Since we don't need global sysctl initialization. To make things clean and simple, remove the global pernet_operations and smc_sysctl_{init|exit}. Call smc_sysctl_net_{init|exit} directly from smc_net_{init|exit}. Also initialized sysctl_autocorking_size if CONFIG_SYSCTL it not set, this make sure SMC autocorking is enabled by default if CONFIG_SYSCTL is not set. Fixes: 462791bbfa35 ("net/smc: add sysctl interface for SMC") Reported-by: kernel test robot Signed-off-by: Dust Li Tested-by: Randy Dunlap # build-tested Signed-off-by: David S. Miller

net/smc: add sysctl interface for SMC

2022-03-01T14:25:12+00:00

This patch add sysctl interface to support container environment for SMC as we talk in the mail list. Link: https://lore.kernel.org/netdev/20220224020253.GF5443@linux.alibaba.com Co-developed-by: Tony Lu Signed-off-by: Tony Lu Signed-off-by: Dust Li Signed-off-by: David S. Miller

net/smc: Introduce tracepoint for fallback

2021-11-01T13:39:14+00:00

This introduces tracepoint for smc fallback to TCP, so that we can track which connection and why it fallbacks, and map the clcsocks' pointer with /proc/net/tcp to find more details about TCP connections. Compared with kprobe or other dynamic tracing, tracepoints are stable and easy to use. Signed-off-by: Tony Lu Reviewed-by: Wen Gu Signed-off-by: David S. Miller

net/smc: Add SMC statistics support

2021-06-16T19:54:02+00:00

Add the ability to collect SMC statistics information. Per-cpu variables are used to collect the statistic information for better performance and for reducing concurrency pitfalls. The code that is collecting statistic data is implemented in macros to increase code reuse and readability. Signed-off-by: Guvenc Gulce Signed-off-by: Karsten Graul Signed-off-by: David S. Miller

net/smc: Introduce generic netlink interface for diagnostic purposes

2020-12-02T01:56:12+00:00

Introduce generic netlink interface infrastructure to expose the diagnostic information regarding smc linkgroups, links and devices. Signed-off-by: Guvenc Gulce Signed-off-by: Karsten Graul Signed-off-by: Jakub Kicinski

treewide: Add SPDX license identifier - Makefile/Kconfig

2019-05-21T08:50:46+00:00

Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman