I2O: handle sysfs_create_link() failures

Compile warning:
ignoring return value of `sysfs_create_link', declared with attribute warn_unused_result.

If sysfs_create_link failed, take care of the return value and do some
error handle after the failure.

Since sysfs_remove_link() will check whether a link exists, when removing the
link in error path, we don't need to care whether a link was created.

Signed-off-by: Wang Chen <wangchen@cn.fujitsu.com>
Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 42 insertions, 12 deletions

diff --git a/drivers/message/i2o/device.c b/drivers/message/i2o/device.c
index 489d7c5c4965..8774c670e668 100644
--- a/drivers/message/i2o/device.c
+++ b/drivers/message/i2o/device.c
@@ -243,29 +243,41 @@ static int i2o_device_add(struct i2o_controller *c, i2o_lct_entry *entry)
 
         /* create user entries for this device */
         tmp = i2o_iop_find_device(i2o_dev->iop, i2o_dev->lct_data.user_tid);
-        if (tmp && (tmp != i2o_dev))
-                sysfs_create_link(&i2o_dev->device.kobj, &tmp->device.kobj,
-                                  "user");
+        if (tmp && (tmp != i2o_dev)) {
+                rc = sysfs_create_link(&i2o_dev->device.kobj,
+                                       &tmp->device.kobj, "user");
+                if (rc)
+                        goto unreg_dev;
+        }
 
         /* create user entries refering to this device */
         list_for_each_entry(tmp, &c->devices, list)
             if ((tmp->lct_data.user_tid == i2o_dev->lct_data.tid)
-                && (tmp != i2o_dev))
-                sysfs_create_link(&tmp->device.kobj,
-                                  &i2o_dev->device.kobj, "user");
+                && (tmp != i2o_dev)) {
+                rc = sysfs_create_link(&tmp->device.kobj,
+                                       &i2o_dev->device.kobj, "user");
+                if (rc)
+                        goto rmlink1;
+        }
 
         /* create parent entries for this device */
         tmp = i2o_iop_find_device(i2o_dev->iop, i2o_dev->lct_data.parent_tid);
-        if (tmp && (tmp != i2o_dev))
-                sysfs_create_link(&i2o_dev->device.kobj, &tmp->device.kobj,
-                                  "parent");
+        if (tmp && (tmp != i2o_dev)) {
+                rc = sysfs_create_link(&i2o_dev->device.kobj,
+                                       &tmp->device.kobj, "parent");
+                if (rc)
+                        goto rmlink1;
+        }
 
         /* create parent entries refering to this device */
         list_for_each_entry(tmp, &c->devices, list)
             if ((tmp->lct_data.parent_tid == i2o_dev->lct_data.tid)
-                && (tmp != i2o_dev))
-                sysfs_create_link(&tmp->device.kobj,
-                                  &i2o_dev->device.kobj, "parent");
+                && (tmp != i2o_dev)) {
+                rc = sysfs_create_link(&tmp->device.kobj,
+                                       &i2o_dev->device.kobj, "parent");
+                if (rc)
+                        goto rmlink2;
+        }
 
         i2o_driver_notify_device_add_all(i2o_dev);
 
@@ -273,6 +285,24 @@ static int i2o_device_add(struct i2o_controller *c, i2o_lct_entry *entry)
 
         return 0;
 
+rmlink2:
+        /* If link creating failed halfway, we loop whole list to cleanup.
+         * And we don't care wrong removing of link, because sysfs_remove_link
+         * will take care of it.
+         */
+        list_for_each_entry(tmp, &c->devices, list) {
+                if (tmp->lct_data.parent_tid == i2o_dev->lct_data.tid)
+                        sysfs_remove_link(&tmp->device.kobj, "parent");
+        }
+        sysfs_remove_link(&i2o_dev->device.kobj, "parent");
+rmlink1:
+        list_for_each_entry(tmp, &c->devices, list)
+                if (tmp->lct_data.user_tid == i2o_dev->lct_data.tid)
+                        sysfs_remove_link(&tmp->device.kobj, "user");
+        sysfs_remove_link(&i2o_dev->device.kobj, "user");
+unreg_dev:
+        list_del(&i2o_dev->list);
+        device_unregister(&i2o_dev->device);
 err:
         kfree(i2o_dev);
         return rc;