xfs: handle duplicate entries in xfs_mru_cache_insert

The radix tree code can detect and reject duplicate keys at insert
time.  Make xfs_mru_cache_insert handle this case so that future
changes to the filestream allocator can take advantage of this.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>

1 files changed, 11 insertions, 3 deletions

diff --git a/fs/xfs/xfs_mru_cache.c b/fs/xfs/xfs_mru_cache.c
index 4aff56395732..4aa316644721 100644
--- a/fs/xfs/xfs_mru_cache.c
+++ b/fs/xfs/xfs_mru_cache.c
@@ -443,6 +443,7 @@ xfs_mru_cache_insert(
         void            *value)
 {
         xfs_mru_cache_elem_t *elem;
+        int error;
 
         ASSERT(mru && mru->lists);
         if (!mru || !mru->lists)
@@ -453,8 +454,8 @@ xfs_mru_cache_insert(
                 return ENOMEM;
 
         if (radix_tree_preload(GFP_KERNEL)) {
-                kmem_zone_free(xfs_mru_elem_zone, elem);
-                return ENOMEM;
+                error = ENOMEM;
+                goto out_free_item;
         }
 
         INIT_LIST_HEAD(&elem->list_node);
@@ -463,13 +464,20 @@ xfs_mru_cache_insert(
 
         spin_lock(&mru->lock);
 
-        radix_tree_insert(&mru->store, key, elem);
+        error = -radix_tree_insert(&mru->store, key, elem);
         radix_tree_preload_end();
+        if (error) {
+                spin_unlock(&mru->lock);
+                goto out_free_item;
+        }
         _xfs_mru_cache_list_insert(mru, elem);
 
         spin_unlock(&mru->lock);
 
         return 0;
+out_free_item:
+        kmem_zone_free(xfs_mru_elem_zone, elem);
+        return error;
 }
 
 /*