net/smc: disable SEID on non-s390 archs where virtual ISM may be used

[ Upstream commit c6b8b8eb49904018e22e4e4b1fa502e57dc747d9 ]

The system EID (SEID) is an internal EID used by SMC-D to represent the
s390 physical machine that OS is executing on. On s390 architecture, it
predefined by fixed string and part of cpuid and is enabled regardless
of whether underlay device is virtual ISM or platform firmware ISM.

However on non-s390 architectures where SMC-D can be used with virtual
ISM devices, there is no similar information to identify physical
machines, especially in virtualization scenarios. So in such cases, SEID
is forcibly disabled and the user-defined UEID will be used to represent
the communicable space.

Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Reviewed-and-tested-by: Wenjia Zhang <wenjia@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Wen Gu 2023-12-19 22:26:15 +08:00 committed by Greg Kroah-Hartman
parent 100089a1ec
commit d1f1e11b3d
1 changed files with 14 additions and 0 deletions

View File

@ -155,10 +155,12 @@ static int smc_clc_ueid_remove(char *ueid)
rc = 0;
}
}
#if IS_ENABLED(CONFIG_S390)
if (!rc && !smc_clc_eid_table.ueid_cnt) {
smc_clc_eid_table.seid_enabled = 1;
rc = -EAGAIN; /* indicate success and enabling of seid */
}
#endif
write_unlock(&smc_clc_eid_table.lock);
return rc;
}
@ -273,22 +275,30 @@ err:
int smc_nl_enable_seid(struct sk_buff *skb, struct genl_info *info)
{
#if IS_ENABLED(CONFIG_S390)
write_lock(&smc_clc_eid_table.lock);
smc_clc_eid_table.seid_enabled = 1;
write_unlock(&smc_clc_eid_table.lock);
return 0;
#else
return -EOPNOTSUPP;
#endif
}
int smc_nl_disable_seid(struct sk_buff *skb, struct genl_info *info)
{
int rc = 0;
#if IS_ENABLED(CONFIG_S390)
write_lock(&smc_clc_eid_table.lock);
if (!smc_clc_eid_table.ueid_cnt)
rc = -ENOENT;
else
smc_clc_eid_table.seid_enabled = 0;
write_unlock(&smc_clc_eid_table.lock);
#else
rc = -EOPNOTSUPP;
#endif
return rc;
}
@ -1269,7 +1279,11 @@ void __init smc_clc_init(void)
INIT_LIST_HEAD(&smc_clc_eid_table.list);
rwlock_init(&smc_clc_eid_table.lock);
smc_clc_eid_table.ueid_cnt = 0;
#if IS_ENABLED(CONFIG_S390)
smc_clc_eid_table.seid_enabled = 1;
#else
smc_clc_eid_table.seid_enabled = 0;
#endif
}
void smc_clc_exit(void)