RDMA/cxgb4: Register RDMA provider based on LLD state_change events

The LLD now supports proper UP state change events, so move the RDMA
provider registration to UP path.

This fixes a crash when loading iw_cxgb4 _after_ the NFS/RDMA
transport is up and running.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

3 files changed, 39 insertions, 10 deletions

diff --git a/drivers/infiniband/hw/cxgb4/device.c b/drivers/infiniband/hw/cxgb4/device.c
index c7e2484e7219..d870f9c17c1e 100644
--- a/drivers/infiniband/hw/cxgb4/device.c
+++ b/drivers/infiniband/hw/cxgb4/device.c
@@ -306,7 +306,8 @@ static void c4iw_remove(struct c4iw_dev *dev)
         PDBG("%s c4iw_dev %p\n", __func__,  dev);
         cancel_delayed_work_sync(&dev->db_drop_task);
         list_del(&dev->entry);
-        c4iw_unregister_device(dev);
+        if (dev->registered)
+                c4iw_unregister_device(dev);
         c4iw_rdev_close(&dev->rdev);
         idr_destroy(&dev->cqidr);
         idr_destroy(&dev->qpidr);
@@ -343,12 +344,6 @@ static struct c4iw_dev *c4iw_alloc(const struct cxgb4_lld_info *infop)
         list_add_tail(&devp->entry, &dev_list);
         mutex_unlock(&dev_mutex);
 
-        if (c4iw_register_device(devp)) {
-                printk(KERN_ERR MOD "Unable to register device\n");
-                mutex_lock(&dev_mutex);
-                c4iw_remove(devp);
-                mutex_unlock(&dev_mutex);
-        }
         if (c4iw_debugfs_root) {
                 devp->debugfs_root = debugfs_create_dir(
                                         pci_name(devp->rdev.lldi.pdev),
@@ -379,9 +374,6 @@ static void *c4iw_uld_add(const struct cxgb4_lld_info *infop)
 
         for (i = 0; i < dev->rdev.lldi.nrxq; i++)
                 PDBG("rxqid[%u] %u\n", i, dev->rdev.lldi.rxq_ids[i]);
-
-        printk(KERN_INFO MOD "Initialized device %s\n",
-               pci_name(dev->rdev.lldi.pdev));
 out:
         return dev;
 }
@@ -471,7 +463,41 @@ nomem:
 
 static int c4iw_uld_state_change(void *handle, enum cxgb4_state new_state)
 {
+        struct c4iw_dev *dev = handle;
+
         PDBG("%s new_state %u\n", __func__, new_state);
+        switch (new_state) {
+        case CXGB4_STATE_UP:
+                printk(KERN_INFO MOD "%s: Up\n", pci_name(dev->rdev.lldi.pdev));
+                if (!dev->registered) {
+                        int ret;
+                        ret = c4iw_register_device(dev);
+                        if (ret)
+                                printk(KERN_ERR MOD
+                                       "%s: RDMA registration failed: %d\n",
+                                       pci_name(dev->rdev.lldi.pdev), ret);
+                }
+                break;
+        case CXGB4_STATE_DOWN:
+                printk(KERN_INFO MOD "%s: Down\n",
+                       pci_name(dev->rdev.lldi.pdev));
+                if (dev->registered)
+                        c4iw_unregister_device(dev);
+                break;
+        case CXGB4_STATE_START_RECOVERY:
+                printk(KERN_INFO MOD "%s: Fatal Error\n",
+                       pci_name(dev->rdev.lldi.pdev));
+                if (dev->registered)
+                        c4iw_unregister_device(dev);
+                break;
+        case CXGB4_STATE_DETACH:
+                printk(KERN_INFO MOD "%s: Detach\n",
+                       pci_name(dev->rdev.lldi.pdev));
+                mutex_lock(&dev_mutex);
+                c4iw_remove(dev);
+                mutex_unlock(&dev_mutex);
+                break;
+        }
         return 0;
 }
 
diff --git a/drivers/infiniband/hw/cxgb4/iw_cxgb4.h b/drivers/infiniband/hw/cxgb4/iw_cxgb4.h
index a6269981e815..277ab589b44d 100644
--- a/drivers/infiniband/hw/cxgb4/iw_cxgb4.h
+++ b/drivers/infiniband/hw/cxgb4/iw_cxgb4.h
@@ -152,6 +152,7 @@ struct c4iw_dev {
         struct list_head entry;
         struct delayed_work db_drop_task;
         struct dentry *debugfs_root;
+        u8 registered;
 };
 
 static inline struct c4iw_dev *to_c4iw_dev(struct ib_device *ibdev)
diff --git a/drivers/infiniband/hw/cxgb4/provider.c b/drivers/infiniband/hw/cxgb4/provider.c
index dfc49020bb9c..322134bb8b73 100644
--- a/drivers/infiniband/hw/cxgb4/provider.c
+++ b/drivers/infiniband/hw/cxgb4/provider.c
@@ -496,6 +496,7 @@ int c4iw_register_device(struct c4iw_dev *dev)
                 if (ret)
                         goto bail2;
         }
+        dev->registered = 1;
         return 0;
 bail2:
         ib_unregister_device(&dev->ibdev);
@@ -514,5 +515,6 @@ void c4iw_unregister_device(struct c4iw_dev *dev)
                                    c4iw_class_attributes[i]);
         ib_unregister_device(&dev->ibdev);
         kfree(dev->ibdev.iwcm);
+        dev->registered = 0;
         return;
 }