[PATCH 05/15] genhd: Return error from disk_{add,alloc}_events

[Fam Zheng]

disk_alloc_events and disk_add_events can fail, return the error code so
the caller can handle it.

Signed-off-by: Fam Zheng <f...@redhat.com>
---
 block/genhd.c | 24 +++++++++++++++---------
 1 file changed, 15 insertions(+), 9 deletions(-)

diff --git a/block/genhd.c b/block/genhd.c
index 8c7510d..4316d2d 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -40,8 +40,8 @@ static struct device_type disk_type;
 
 static void disk_check_events(struct disk_events *ev,
                              unsigned int *clearing_ptr);
-static void disk_alloc_events(struct gendisk *disk);
-static void disk_add_events(struct gendisk *disk);
+static int disk_alloc_events(struct gendisk *disk);
+static int disk_add_events(struct gendisk *disk);
 static void disk_del_events(struct gendisk *disk);
 static void disk_release_events(struct gendisk *disk);
 
@@ -1823,17 +1823,17 @@ module_param_cb(events_dfl_poll_msecs, 
&disk_events_dfl_poll_msecs_param_ops,
 /*
  * disk_{alloc|add|del|release}_events - initialize and destroy disk_events.
  */
-static void disk_alloc_events(struct gendisk *disk)
+static int disk_alloc_events(struct gendisk *disk)
 {
        struct disk_events *ev;
 
        if (!disk->fops->check_events)
-               return;
+               return 0;
 
        ev = kzalloc(sizeof(*ev), GFP_KERNEL);
        if (!ev) {
                pr_warn("%s: failed to initialize events\n", disk->disk_name);
-               return;
+               return -ENOMEM;
        }
 
        INIT_LIST_HEAD(&ev->node);
@@ -1845,17 +1845,22 @@ static void disk_alloc_events(struct gendisk *disk)
        INIT_DELAYED_WORK(&ev->dwork, disk_events_workfn);
 
        disk->ev = ev;
+       return 0;
 }
 
-static void disk_add_events(struct gendisk *disk)
+static int disk_add_events(struct gendisk *disk)
 {
+       int rc;
+
        if (!disk->ev)
-               return;
+               return 0;
 
-       /* FIXME: error handling */
-       if (sysfs_create_files(&disk_to_dev(disk)->kobj, disk_events_attrs) < 0)
+       rc = sysfs_create_files(&disk_to_dev(disk)->kobj, disk_events_attrs);
+       if (rc) {
                pr_warn("%s: failed to create sysfs files for events\n",
                        disk->disk_name);
+               return rc;
+       }
 
        mutex_lock(&disk_events_mutex);
        list_add_tail(&disk->ev->node, &disk_events);
@@ -1866,6 +1871,7 @@ static void disk_add_events(struct gendisk *disk)
         * unblock kicks it into action.
         */
        __disk_unblock_events(disk, true);
+       return 0;
 }
 
 static void disk_del_events(struct gendisk *disk)
-- 
2.7.4