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

From: Guangguan Wang
Date: Mon Oct 16 2023 - 02:12:06 EST


The function smc_find_ism_store_rc is not only used for ism, so it is
reasonable to change the function name to smc_find_device_store_rc.

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@xxxxxxxxxxxxxxxxx>
---
net/smc/af_smc.c | 23 +++++++++--------------
1 file changed, 9 insertions(+), 14 deletions(-)

diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index bacdd971615e..15d8ad7af75d 100644
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -2121,7 +2121,7 @@ static void smc_check_ism_v2_match(struct smc_init_info *ini,
}
}

-static void smc_find_ism_store_rc(u32 rc, struct smc_init_info *ini)
+static void smc_find_device_store_rc(u32 rc, struct smc_init_info *ini)
{
if (!ini->rc)
ini->rc = rc;
@@ -2162,10 +2162,8 @@ 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_ism_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,
@@ -2180,7 +2178,7 @@ static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc,
ini->ism_selected = i;
rc = smc_listen_ism_init(new_smc, ini);
if (rc) {
- smc_find_ism_store_rc(rc, ini);
+ smc_find_device_store_rc(rc, ini);
/* try next active ISM device */
continue;
}
@@ -2213,11 +2211,12 @@ static void smc_find_ism_v1_device_serv(struct smc_sock *new_smc,
goto not_found;
ini->ism_selected = 0;
rc = smc_listen_ism_init(new_smc, ini);
- if (!rc)
+ if (!rc) {
+ smc_find_device_store_rc(rc, ini);
return; /* V1 ISM device found */
+ }

not_found:
- smc_find_ism_store_rc(rc, ini);
ini->smcd_version &= ~SMC_V1;
ini->ism_dev[0] = NULL;
ini->is_smcd = false;
@@ -2266,10 +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_ism_store_rc(rc, ini);
+ if (rc)
goto not_found;
- }
if (!ini->smcrv2.uses_gateway)
memcpy(ini->smcrv2.nexthop_mac, pclc->lcl.mac, ETH_ALEN);

@@ -2284,7 +2281,7 @@ static void smc_find_rdma_v2_device_serv(struct smc_sock *new_smc,
if (!rc)
return;
ini->smcr_version = smcr_version;
- smc_find_ism_store_rc(rc, ini);
+ smc_find_device_store_rc(rc, ini);

not_found:
ini->smcr_version &= ~SMC_V2;
@@ -2330,8 +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_ism_store_rc(prfx_rc, ini);

/* get vlan id from IP device */
if (smc_vlan_by_tcpsk(new_smc->clcsock, ini))
@@ -2358,7 +2353,7 @@ static int smc_listen_find_device(struct smc_sock *new_smc,
int rc;

rc = smc_find_rdma_v1_device_serv(new_smc, pclc, ini);
- smc_find_ism_store_rc(rc, ini);
+ smc_find_device_store_rc(rc, ini);
return (!rc) ? 0 : ini->rc;
}
return SMC_CLC_DECL_NOSMCDEV;
--
2.24.3 (Apple Git-128)