ipmi: Rework BMC registration

There was a certain error case where the BMC wouldn't be deregistered
like it should be.  Rework the BMC registration to make calling
ipmi_bmc_unregister() ok even if it's not registered and to clean up
the error handling for ipmi_bmc_register().

Signed-off-by: Corey Minyard <cminyard@mvista.com>

diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c
index 42532f2..1517f14 100644 (file)
--- a/drivers/char/ipmi/ipmi_msghandler.c
+++ b/drivers/char/ipmi/ipmi_msghandler.c
@@ -404,6 +404,7 @@ struct ipmi_smi {
        wait_queue_head_t waitq;
 
        struct bmc_device *bmc;
+       bool bmc_registered;
        char *my_dev_name;
 
        /*
@@ -2524,17 +2525,18 @@ static void ipmi_bmc_unregister(ipmi_smi_t intf)
 {
        struct bmc_device *bmc = intf->bmc;
 
+       if (!intf->bmc_registered)
+               return;
+
        sysfs_remove_link(&intf->si_dev->kobj, "bmc");
-       if (intf->my_dev_name) {
-               sysfs_remove_link(&bmc->pdev.dev.kobj, intf->my_dev_name);
-               kfree(intf->my_dev_name);
-               intf->my_dev_name = NULL;
-       }
+       sysfs_remove_link(&bmc->pdev.dev.kobj, intf->my_dev_name);
+       kfree(intf->my_dev_name);
+       intf->my_dev_name = NULL;
 
        mutex_lock(&ipmidriver_mutex);
        kref_put(&bmc->usecount, cleanup_bmc_device);
        mutex_unlock(&ipmidriver_mutex);
-       intf->bmc = NULL;
+       intf->bmc_registered = false;
 }
 
 static int ipmi_bmc_register(ipmi_smi_t intf, int ifnum)
@@ -2600,7 +2602,9 @@ static int ipmi_bmc_register(ipmi_smi_t intf, int ifnum)
                        if (bmc->id.device_id == orig_dev_id) {
                                printk(KERN_ERR PFX
                                       "Out of device ids!\n");
-                               break;
+                               mutex_unlock(&ipmidriver_mutex);
+                               rv = -EAGAIN;
+                               goto out;
                        }
                }
 
@@ -2613,16 +2617,11 @@ static int ipmi_bmc_register(ipmi_smi_t intf, int ifnum)
                rv = platform_device_register(&bmc->pdev);
                mutex_unlock(&ipmidriver_mutex);
                if (rv) {
-                       put_device(&bmc->pdev.dev);
                        printk(KERN_ERR
                               "ipmi_msghandler:"
                               " Unable to register bmc device: %d\n",
                               rv);
-                       /*
-                        * Don't go to out_err, you can only do that if
-                        * the device is registered already.
-                        */
-                       return rv;
+                       goto out_list_del;
                }
 
                dev_info(intf->si_dev, "Found new BMC (man_id: 0x%6.6x, "
@@ -2641,7 +2640,7 @@ static int ipmi_bmc_register(ipmi_smi_t intf, int ifnum)
                printk(KERN_ERR
                       "ipmi_msghandler: Unable to create bmc symlink: %d\n",
                       rv);
-               goto out_err;
+               goto out_put_bmc;
        }
 
        intf->my_dev_name = kasprintf(GFP_KERNEL, "ipmi%d", ifnum);
@@ -2650,7 +2649,7 @@ static int ipmi_bmc_register(ipmi_smi_t intf, int ifnum)
                printk(KERN_ERR
                       "ipmi_msghandler: allocate link from BMC: %d\n",
                       rv);
-               goto out_err;
+               goto out_unlink1;
        }
 
        rv = sysfs_create_link(&bmc->pdev.dev.kobj, &intf->si_dev->kobj,
@@ -2662,14 +2661,35 @@ static int ipmi_bmc_register(ipmi_smi_t intf, int ifnum)
                       "ipmi_msghandler:"
                       " Unable to create symlink to bmc: %d\n",
                       rv);
-               goto out_err;
+               goto out_free_my_dev_name;
        }
 
-       return 0;
+       intf->bmc_registered = true;
 
-out_err:
-       ipmi_bmc_unregister(intf);
+out:
        return rv;
+
+
+out_free_my_dev_name:
+       kfree(intf->my_dev_name);
+       intf->my_dev_name = NULL;
+
+out_unlink1:
+       sysfs_remove_link(&intf->si_dev->kobj, "bmc");
+
+out_put_bmc:
+       mutex_lock(&ipmidriver_mutex);
+       intf->bmc = NULL;
+       kref_put(&bmc->usecount, cleanup_bmc_device);
+       mutex_unlock(&ipmidriver_mutex);
+       goto out;
+
+out_list_del:
+       mutex_lock(&ipmidriver_mutex);
+       intf->bmc = NULL;
+       mutex_unlock(&ipmidriver_mutex);
+       put_device(&bmc->pdev.dev);
+       goto out;
 }
 
 static int
@@ -2959,6 +2979,10 @@ int ipmi_register_smi(const struct ipmi_smi_handlers *handlers,
 
        get_guid(intf);
 
+       rv = ipmi_bmc_register(intf, i);
+       if (rv)
+               goto out;
+
        if ((intf->ipmi_version_major > 1)
                        || ((intf->ipmi_version_major == 1)
                            && (intf->ipmi_version_minor >= 5))) {
@@ -2987,13 +3011,11 @@ int ipmi_register_smi(const struct ipmi_smi_handlers *handlers,
                intf->curr_channel = IPMI_MAX_CHANNELS;
        }
 
-       rv = ipmi_bmc_register(intf, i);
-
-       if (rv == 0)
-               rv = add_proc_entries(intf, i);
+       rv = add_proc_entries(intf, i);
 
  out:
        if (rv) {
+               ipmi_bmc_unregister(intf);
                if (intf->proc_dir)
                        remove_proc_entries(intf);
                intf->handlers = NULL;