net/smc: add smcr_port_add() and smcr_link_up() processing

Call smcr_port_add() when an IB event reports a new active IB device.
smcr_port_add() will start a work which either triggers the local
ADD_LINK processing, or send an ADD_LINK LLC message to the SMC server
to initiate the processing.

Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index d7ab92f..20bc9e4 100644 (file)
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -44,10 +44,19 @@ static struct smc_lgr_list smc_lgr_list = { /* established link groups */
 static atomic_t lgr_cnt = ATOMIC_INIT(0); /* number of existing link groups */
 static DECLARE_WAIT_QUEUE_HEAD(lgrs_deleted);
 
+struct smc_ib_up_work {
+       struct work_struct      work;
+       struct smc_link_group   *lgr;
+       struct smc_ib_device    *smcibdev;
+       u8                      ibport;
+};
+
 static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
                         struct smc_buf_desc *buf_desc);
 static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft);
 
+static void smc_link_up_work(struct work_struct *work);
+
 /* return head of link group list and its lock for a given link group */
 static inline struct list_head *smc_lgr_list_head(struct smc_link_group *lgr,
                                                  spinlock_t **lgr_lock)
@@ -928,6 +937,83 @@ void smc_smcr_terminate_all(struct smc_ib_device *smcibdev)
        }
 }
 
+/* link is up - establish alternate link if applicable */
+static void smcr_link_up(struct smc_link_group *lgr,
+                        struct smc_ib_device *smcibdev, u8 ibport)
+{
+       struct smc_link *link = NULL;
+
+       if (list_empty(&lgr->list) ||
+           lgr->type == SMC_LGR_SYMMETRIC ||
+           lgr->type == SMC_LGR_ASYMMETRIC_PEER)
+               return;
+
+       if (lgr->role == SMC_SERV) {
+               /* trigger local add link processing */
+               link = smc_llc_usable_link(lgr);
+               if (!link)
+                       return;
+               /* tbd: call smc_llc_srv_add_link_local(link); */
+       } else {
+               /* invite server to start add link processing */
+               u8 gid[SMC_GID_SIZE];
+
+               if (smc_ib_determine_gid(smcibdev, ibport, lgr->vlan_id, gid,
+                                        NULL))
+                       return;
+               if (lgr->llc_flow_lcl.type != SMC_LLC_FLOW_NONE) {
+                       /* some other llc task is ongoing */
+                       wait_event_interruptible_timeout(lgr->llc_waiter,
+                               (lgr->llc_flow_lcl.type == SMC_LLC_FLOW_NONE),
+                               SMC_LLC_WAIT_TIME);
+               }
+               if (list_empty(&lgr->list) ||
+                   !smc_ib_port_active(smcibdev, ibport))
+                       return; /* lgr or device no longer active */
+               link = smc_llc_usable_link(lgr);
+               if (!link)
+                       return;
+               smc_llc_send_add_link(link, smcibdev->mac[ibport - 1], gid,
+                                     NULL, SMC_LLC_REQ);
+       }
+}
+
+void smcr_port_add(struct smc_ib_device *smcibdev, u8 ibport)
+{
+       struct smc_ib_up_work *ib_work;
+       struct smc_link_group *lgr, *n;
+
+       list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
+               if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
+                           SMC_MAX_PNETID_LEN) ||
+                   lgr->type == SMC_LGR_SYMMETRIC ||
+                   lgr->type == SMC_LGR_ASYMMETRIC_PEER)
+                       continue;
+               ib_work = kmalloc(sizeof(*ib_work), GFP_KERNEL);
+               if (!ib_work)
+                       continue;
+               INIT_WORK(&ib_work->work, smc_link_up_work);
+               ib_work->lgr = lgr;
+               ib_work->smcibdev = smcibdev;
+               ib_work->ibport = ibport;
+               schedule_work(&ib_work->work);
+       }
+}
+
+static void smc_link_up_work(struct work_struct *work)
+{
+       struct smc_ib_up_work *ib_work = container_of(work,
+                                                     struct smc_ib_up_work,
+                                                     work);
+       struct smc_link_group *lgr = ib_work->lgr;
+
+       if (list_empty(&lgr->list))
+               goto out;
+       smcr_link_up(lgr, ib_work->smcibdev, ib_work->ibport);
+out:
+       kfree(ib_work);
+}
+
 /* Determine vlan of internal TCP socket.
  * @vlan_id: address to store the determined vlan id into
  */

diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h
index 413eaad..86453ad 100644 (file)
--- a/net/smc/smc_core.h
+++ b/net/smc/smc_core.h
@@ -345,6 +345,7 @@ void smc_lgr_forget(struct smc_link_group *lgr);
 void smc_lgr_cleanup_early(struct smc_connection *conn);
 void smc_lgr_terminate_sched(struct smc_link_group *lgr);
 void smc_port_terminate(struct smc_ib_device *smcibdev, u8 ibport);
+void smcr_port_add(struct smc_ib_device *smcibdev, u8 ibport);
 void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid,
                        unsigned short vlan);
 void smc_smcd_terminate_all(struct smcd_dev *dev);

diff --git a/net/smc/smc_ib.c b/net/smc/smc_ib.c
index c090678..545fb0b 100644 (file)
--- a/net/smc/smc_ib.c
+++ b/net/smc/smc_ib.c
@@ -252,6 +252,7 @@ static void smc_ib_port_event_work(struct work_struct *work)
                        smc_port_terminate(smcibdev, port_idx + 1);
                } else {
                        clear_bit(port_idx, smcibdev->ports_going_away);
+                       smcr_port_add(smcibdev, port_idx + 1);
                }
        }
 }