[PATCH net v2 2/2] net/smc: correct the reason code in smc_listen_find_device when fallback

Guangguan Wang
2023-10-17T12:42:51Z

The ini->rc is used to store the last error happened when finding usable
ism or rdma device in smc_listen_find_device, and is set by calling smc_
find_device_store_rc. Once the ini->rc is assigned to an none-zero value,
the value can not be overwritten anymore. So the ini-rc should be set to
the error reason only when an error actually occurs.

When finding ISM/RDMA devices, device not found is not a real error, as
not all machine have ISM/RDMA devices. Failures after device found, when
initializing device or when initializing connection, is real errors, and
should be store in ini->rc.

SMC_CLC_DECL_DIFFPREFIX also is not a real error, as for SMC-RV2, it is
not require same prefix.

Signed-off-by: Guangguan Wang <guangguan.wang@linux.alibaba.com>
---
net/smc/af_smc.c | 12 +++---------
1 file changed, 3 insertions(+), 9 deletions(-)

diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index b3a67a168495..21e9c6ec4d01 100644
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -2163,10 +2163,8 @@ static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc,
}
mutex_unlock(&smcd_dev_list.mutex);

- if (!ini->ism_dev[0]) {
- smc_find_device_store_rc(SMC_CLC_DECL_NOSMCD2DEV, ini);
+ if (!ini->ism_dev[0])
goto not_found;
- }

smc_ism_get_system_eid(&eid);
if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext,
@@ -2216,9 +2214,9 @@ static void smc_find_ism_v1_device_serv(struct smc_sock *new_smc,
rc = smc_listen_ism_init(new_smc, ini);
if (!rc)
return; /* V1 ISM device found */
+ smc_find_device_store_rc(rc, ini);

not_found:
- smc_find_device_store_rc(rc, ini);
ini->smcd_version &= ~SMC_V1;
ini->ism_dev[0] = NULL;
ini->is_smcd = false;
@@ -2267,10 +2265,8 @@ static void smc_find_rdma_v2_device_serv(struct smc_sock *new_smc,
ini->smcrv2.saddr = new_smc->clcsock->sk->sk_rcv_saddr;
ini->smcrv2.daddr = smc_ib_gid_to_ipv4(smc_v2_ext->roce);
rc = smc_find_rdma_device(new_smc, ini);
- if (rc) {
- smc_find_device_store_rc(rc, ini);
+ if (rc)
goto not_found;
- }
if (!ini->smcrv2.uses_gateway)
memcpy(ini->smcrv2.nexthop_mac, pclc->lcl.mac, ETH_ALEN);

@@ -2331,8 +2327,6 @@ static int smc_listen_find_device(struct smc_sock *new_smc,

/* check for matching IP prefix and subnet length (V1) */
prfx_rc = smc_listen_prfx_check(new_smc, pclc);
- if (prfx_rc)
- smc_find_device_store_rc(prfx_rc, ini);

/* get vlan id from IP device */
if (smc_vlan_by_tcpsk(new_smc->clcsock, ini))
--
2.24.3 (Apple Git-128)