net/smc: register loopback-ism into SMC-D device list

After the loopback-ism device is ready, add it to the SMC-D device list
as an ISMv2 device, and always keep it at the beginning to ensure it is
preferred for providing a shortcut for data transfer within the same
kernel.

Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Reviewed-and-tested-by: Jan Karcher <jaka@linux.ibm.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

diff --git a/net/smc/smc_ism.c b/net/smc/smc_ism.c
index 188fd28423c2be1b54b5bf47cd7eae0f620e7839..6bed0a61b746b621103ddb4eee159803535d3ded 100644 (file)
--- a/net/smc/smc_ism.c
+++ b/net/smc/smc_ism.c
@@ -91,6 +91,11 @@ bool smc_ism_is_v2_capable(void)
        return smc_ism_v2_capable;
 }
 
+void smc_ism_set_v2_capable(void)
+{
+       smc_ism_v2_capable = true;
+}
+
 /* Set a connection using this DMBE. */
 void smc_ism_set_conn(struct smc_connection *conn)
 {
@@ -439,7 +444,7 @@ static struct smcd_dev *smcd_alloc_dev(struct device *parent, const char *name,
 static void smcd_register_dev(struct ism_dev *ism)
 {
        const struct smcd_ops *ops = ism_get_smcd_ops();
-       struct smcd_dev *smcd;
+       struct smcd_dev *smcd, *fentry;
 
        if (!ops)
                return;
@@ -454,16 +459,23 @@ static void smcd_register_dev(struct ism_dev *ism)
        if (smc_pnetid_by_dev_port(&ism->pdev->dev, 0, smcd->pnetid))
                smc_pnetid_by_table_smcd(smcd);
 
+       if (smcd->ops->supports_v2())
+               smc_ism_set_v2_capable();
        mutex_lock(&smcd_dev_list.mutex);
-       if (list_empty(&smcd_dev_list.list)) {
-               if (smcd->ops->supports_v2())
-                       smc_ism_v2_capable = true;
-       }
-       /* sort list: devices without pnetid before devices with pnetid */
-       if (smcd->pnetid[0])
+       /* sort list:
+        * - devices without pnetid before devices with pnetid;
+        * - loopback-ism always at the very beginning;
+        */
+       if (!smcd->pnetid[0]) {
+               fentry = list_first_entry_or_null(&smcd_dev_list.list,
+                                                 struct smcd_dev, list);
+               if (fentry && smc_ism_is_loopback(fentry))
+                       list_add(&smcd->list, &fentry->list);
+               else
+                       list_add(&smcd->list, &smcd_dev_list.list);
+       } else {
                list_add_tail(&smcd->list, &smcd_dev_list.list);
-       else
-               list_add(&smcd->list, &smcd_dev_list.list);
+       }
        mutex_unlock(&smcd_dev_list.mutex);
 
        pr_warn_ratelimited("smc: adding smcd device %s with pnetid %.16s%s\n",

diff --git a/net/smc/smc_ism.h b/net/smc/smc_ism.h
index 322973527c61c2402a1a19092615fb7a4feb3fc1..e6f57e5e1ef956586c327d299a805671c0841098 100644 (file)
--- a/net/smc/smc_ism.h
+++ b/net/smc/smc_ism.h
@@ -52,6 +52,7 @@ int smc_ism_signal_shutdown(struct smc_link_group *lgr);
 void smc_ism_get_system_eid(u8 **eid);
 u16 smc_ism_get_chid(struct smcd_dev *dev);
 bool smc_ism_is_v2_capable(void);
+void smc_ism_set_v2_capable(void);
 int smc_ism_init(void);
 void smc_ism_exit(void);
 int smcd_nl_get_device(struct sk_buff *skb, struct netlink_callback *cb);

diff --git a/net/smc/smc_loopback.c b/net/smc/smc_loopback.c
index d75852549b00732fd06cc8a30983b20666eed9e6..94a57f4ee3f945a5ce12f235c466ee456f08219e 100644 (file)
--- a/net/smc/smc_loopback.c
+++ b/net/smc/smc_loopback.c
@@ -246,10 +246,12 @@ static int smcd_lo_register_dev(struct smc_lo_dev *ldev)
                return -ENOMEM;
        ldev->smcd = smcd;
        smcd->priv = ldev;
-
-       /* TODO:
-        * register loopback-ism to smcd_dev list.
-        */
+       smc_ism_set_v2_capable();
+       mutex_lock(&smcd_dev_list.mutex);
+       list_add(&smcd->list, &smcd_dev_list.list);
+       mutex_unlock(&smcd_dev_list.mutex);
+       pr_warn_ratelimited("smc: adding smcd device %s\n",
+                           dev_name(&ldev->dev));
        return 0;
 }
 
@@ -257,9 +259,13 @@ static void smcd_lo_unregister_dev(struct smc_lo_dev *ldev)
 {
        struct smcd_dev *smcd = ldev->smcd;
 
-       /* TODO:
-        * unregister loopback-ism from smcd_dev list.
-        */
+       pr_warn_ratelimited("smc: removing smcd device %s\n",
+                           dev_name(&ldev->dev));
+       smcd->going_away = 1;
+       smc_smcd_terminate_all(smcd);
+       mutex_lock(&smcd_dev_list.mutex);
+       list_del_init(&smcd->list);
+       mutex_unlock(&smcd_dev_list.mutex);
        kfree(smcd->conn);
        kfree(smcd);
 }