diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index cb4096cc3fb7..b85e36e153ba 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -303,7 +303,7 @@ out:
 static DEFINE_IDR(proc_inum_idr);
 static DEFINE_SPINLOCK(proc_inum_lock); /* protects the above */
 
-#define PROC_DYNAMIC_FIRST 0xF0000000UL
+#define PROC_DYNAMIC_FIRST 0xF0000000U
 
 /*
  * Return an inode number between PROC_DYNAMIC_FIRST and
@@ -311,7 +311,7 @@ static DEFINE_SPINLOCK(proc_inum_lock); /* protects the above */
  */
 static unsigned int get_inode_number(void)
 {
-	int i, inum = 0;
+	unsigned int i;
 	int error;
 
 retry:
@@ -326,21 +326,18 @@ retry:
 	else if (error)
 		return 0;
 
-	inum = (i & MAX_ID_MASK) + PROC_DYNAMIC_FIRST;
-
-	/* inum will never be more than 0xf0ffffff, so no check
-	 * for overflow.
-	 */
-
-	return inum;
+	if (i > UINT_MAX - PROC_DYNAMIC_FIRST) {
+		spin_lock(&proc_inum_lock);
+		idr_remove(&proc_inum_idr, i);
+		spin_unlock(&proc_inum_lock);
+	}
+	return PROC_DYNAMIC_FIRST + i;
 }
 
 static void release_inode_number(unsigned int inum)
 {
-	int id = (inum - PROC_DYNAMIC_FIRST) | ~MAX_ID_MASK;
-
 	spin_lock(&proc_inum_lock);
-	idr_remove(&proc_inum_idr, id);
+	idr_remove(&proc_inum_idr, inum - PROC_DYNAMIC_FIRST);
 	spin_unlock(&proc_inum_lock);
 }