mm: bdi init hooks

provide BDI constructor/destructor hooks

[akpm@linux-foundation.org: compile fix]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 10 insertions, 3 deletions

diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c
index 9eabac95fbe0..524404bd08c1 100644
--- a/block/ll_rw_blk.c
+++ b/block/ll_rw_blk.c
@@ -1786,6 +1786,7 @@ static void blk_release_queue(struct kobject *kobj)
 
         blk_trace_shutdown(q);
 
+        bdi_destroy(&q->backing_dev_info);
         kmem_cache_free(requestq_cachep, q);
 }
 
@@ -1839,21 +1840,27 @@ static struct kobj_type queue_ktype;
 struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
 {
         struct request_queue *q;
+        int err;
 
         q = kmem_cache_alloc_node(requestq_cachep,
                                 gfp_mask | __GFP_ZERO, node_id);
         if (!q)
                 return NULL;
 
+        q->backing_dev_info.unplug_io_fn = blk_backing_dev_unplug;
+        q->backing_dev_info.unplug_io_data = q;
+        err = bdi_init(&q->backing_dev_info);
+        if (err) {
+                kmem_cache_free(requestq_cachep, q);
+                return NULL;
+        }
+
         init_timer(&q->unplug_timer);
 
         kobject_set_name(&q->kobj, "%s", "queue");
         q->kobj.ktype = &queue_ktype;
         kobject_init(&q->kobj);
 
-        q->backing_dev_info.unplug_io_fn = blk_backing_dev_unplug;
-        q->backing_dev_info.unplug_io_data = q;
-
         mutex_init(&q->sysfs_lock);
 
         return q;