nvmet-fc: simplify nvmet_fc_alloc_hostport

Once a host is already created, avoid allocate additional hostports that
will be thrown away. add an helper function to handle host search.

Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Amit Engel <amit.engel@dell.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

diff --git a/drivers/nvme/target/fc.c b/drivers/nvme/target/fc.c
index 1f1c70f..19e1132 100644 (file)
--- a/drivers/nvme/target/fc.c
+++ b/drivers/nvme/target/fc.c
@@ -1020,61 +1020,76 @@ nvmet_fc_free_hostport(struct nvmet_fc_hostport *hostport)
        nvmet_fc_hostport_put(hostport);
 }
 
+static struct nvmet_fc_hostport *
+nvmet_fc_match_hostport(struct nvmet_fc_tgtport *tgtport, void *hosthandle)
+{
+       struct nvmet_fc_hostport *host;
+
+       lockdep_assert_held(&tgtport->lock);
+
+       list_for_each_entry(host, &tgtport->host_list, host_list) {
+               if (host->hosthandle == hosthandle && !host->invalid) {
+                       if (nvmet_fc_hostport_get(host))
+                               return (host);
+               }
+       }
+
+       return NULL;
+}
+
 static struct nvmet_fc_hostport *
 nvmet_fc_alloc_hostport(struct nvmet_fc_tgtport *tgtport, void *hosthandle)
 {
-       struct nvmet_fc_hostport *newhost, *host, *match = NULL;
+       struct nvmet_fc_hostport *newhost, *match = NULL;
        unsigned long flags;
 
        /* if LLDD not implemented, leave as NULL */
        if (!hosthandle)
                return NULL;
 
-       /* take reference for what will be the newly allocated hostport */
+       /*
+        * take reference for what will be the newly allocated hostport if
+        * we end up using a new allocation
+        */
        if (!nvmet_fc_tgtport_get(tgtport))
                return ERR_PTR(-EINVAL);
 
+       spin_lock_irqsave(&tgtport->lock, flags);
+       match = nvmet_fc_match_hostport(tgtport, hosthandle);
+       spin_unlock_irqrestore(&tgtport->lock, flags);
+
+       if (match) {
+               /* no new allocation - release reference */
+               nvmet_fc_tgtport_put(tgtport);
+               return match;
+       }
+
        newhost = kzalloc(sizeof(*newhost), GFP_KERNEL);
        if (!newhost) {
-               spin_lock_irqsave(&tgtport->lock, flags);
-               list_for_each_entry(host, &tgtport->host_list, host_list) {
-                       if (host->hosthandle == hosthandle && !host->invalid) {
-                               if (nvmet_fc_hostport_get(host)) {
-                                       match = host;
-                                       break;
-                               }
-                       }
-               }
-               spin_unlock_irqrestore(&tgtport->lock, flags);
-               /* no allocation - release reference */
+               /* no new allocation - release reference */
                nvmet_fc_tgtport_put(tgtport);
-               return (match) ? match : ERR_PTR(-ENOMEM);
+               return ERR_PTR(-ENOMEM);
        }
 
-       newhost->tgtport = tgtport;
-       newhost->hosthandle = hosthandle;
-       INIT_LIST_HEAD(&newhost->host_list);
-       kref_init(&newhost->ref);
-
        spin_lock_irqsave(&tgtport->lock, flags);
-       list_for_each_entry(host, &tgtport->host_list, host_list) {
-               if (host->hosthandle == hosthandle && !host->invalid) {
-                       if (nvmet_fc_hostport_get(host)) {
-                               match = host;
-                               break;
-                       }
-               }
-       }
+       match = nvmet_fc_match_hostport(tgtport, hosthandle);
        if (match) {
+               /* new allocation not needed */
                kfree(newhost);
-               newhost = NULL;
-               /* releasing allocation - release reference */
+               newhost = match;
+               /* no new allocation - release reference */
                nvmet_fc_tgtport_put(tgtport);
-       } else
+       } else {
+               newhost->tgtport = tgtport;
+               newhost->hosthandle = hosthandle;
+               INIT_LIST_HEAD(&newhost->host_list);
+               kref_init(&newhost->ref);
+
                list_add_tail(&newhost->host_list, &tgtport->host_list);
+       }
        spin_unlock_irqrestore(&tgtport->lock, flags);
 
-       return (match) ? match : newhost;
+       return newhost;
 }
 
 static void