1 files changed, 8 insertions, 1 deletions

diff --git a/fs/super.c b/fs/super.c
index d40d53a22fb5..2761d3e22ed9 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -608,6 +608,7 @@ void emergency_remount(void)
 
 static DEFINE_IDA(unnamed_dev_ida);
 static DEFINE_SPINLOCK(unnamed_dev_lock);/* protects the above */
+static int unnamed_dev_start = 0; /* don't bother trying below it */
 
 int set_anon_super(struct super_block *s, void *data)
 {
@@ -618,7 +619,9 @@ int set_anon_super(struct super_block *s, void *data)
         if (ida_pre_get(&unnamed_dev_ida, GFP_ATOMIC) == 0)
                 return -ENOMEM;
         spin_lock(&unnamed_dev_lock);
-        error = ida_get_new(&unnamed_dev_ida, &dev);
+        error = ida_get_new_above(&unnamed_dev_ida, unnamed_dev_start, &dev);
+        if (!error)
+                unnamed_dev_start = dev + 1;
         spin_unlock(&unnamed_dev_lock);
         if (error == -EAGAIN)
                 /* We raced and lost with another CPU. */
@@ -629,6 +632,8 @@ int set_anon_super(struct super_block *s, void *data)
         if ((dev & MAX_ID_MASK) == (1 << MINORBITS)) {
                 spin_lock(&unnamed_dev_lock);
                 ida_remove(&unnamed_dev_ida, dev);
+                if (unnamed_dev_start > dev)
+                        unnamed_dev_start = dev;
                 spin_unlock(&unnamed_dev_lock);
                 return -EMFILE;
         }
@@ -645,6 +650,8 @@ void kill_anon_super(struct super_block *sb)
         generic_shutdown_super(sb);
         spin_lock(&unnamed_dev_lock);
         ida_remove(&unnamed_dev_ida, slot);
+        if (slot < unnamed_dev_start)
+                unnamed_dev_start = slot;
         spin_unlock(&unnamed_dev_lock);
 }