1 files changed, 1 insertions, 60 deletions

diff --git a/ipc/util.c b/ipc/util.c
index 3339177b336c..49b3ea615dc5 100644
--- a/ipc/util.c
+++ b/ipc/util.c
@@ -688,10 +688,6 @@ void ipc64_perm_to_ipc_perm (struct ipc64_perm *in, struct ipc_perm *out)
  * Look for an id in the ipc ids idr and lock the associated ipc object.
  *
  * The ipc object is locked on exit.
- *
- * This is the routine that should be called when the rw_mutex is not already
- * held, i.e. idr tree not protected: it protects the idr tree in read mode
- * during the idr_find().
  */
 
 struct kern_ipc_perm *ipc_lock(struct ipc_ids *ids, int id)
@@ -699,18 +695,13 @@ struct kern_ipc_perm *ipc_lock(struct ipc_ids *ids, int id)
 	struct kern_ipc_perm *out;
 	int lid = ipcid_to_idx(id);
 
-	down_read(&ids->rw_mutex);
-
 	rcu_read_lock();
 	out = idr_find(&ids->ipcs_idr, lid);
 	if (out == NULL) {
 		rcu_read_unlock();
-		up_read(&ids->rw_mutex);
 		return ERR_PTR(-EINVAL);
 	}
 
-	up_read(&ids->rw_mutex);
-
 	spin_lock(&out->lock);
 	
 	/* ipc_rmid() may have already freed the ID while ipc_lock
@@ -725,56 +716,6 @@ struct kern_ipc_perm *ipc_lock(struct ipc_ids *ids, int id)
 	return out;
 }
 
-/**
- * ipc_lock_down - Lock an ipc structure with rw_sem held
- * @ids: IPC identifier set
- * @id: ipc id to look for
- *
- * Look for an id in the ipc ids idr and lock the associated ipc object.
- *
- * The ipc object is locked on exit.
- *
- * This is the routine that should be called when the rw_mutex is already
- * held, i.e. idr tree protected.
- */
-
-struct kern_ipc_perm *ipc_lock_down(struct ipc_ids *ids, int id)
-{
-	struct kern_ipc_perm *out;
-	int lid = ipcid_to_idx(id);
-
-	rcu_read_lock();
-	out = idr_find(&ids->ipcs_idr, lid);
-	if (out == NULL) {
-		rcu_read_unlock();
-		return ERR_PTR(-EINVAL);
-	}
-
-	spin_lock(&out->lock);
-
-	/*
-	 * No need to verify that the structure is still valid since the
-	 * rw_mutex is held.
-	 */
-	return out;
-}
-
-struct kern_ipc_perm *ipc_lock_check_down(struct ipc_ids *ids, int id)
-{
-	struct kern_ipc_perm *out;
-
-	out = ipc_lock_down(ids, id);
-	if (IS_ERR(out))
-		return out;
-
-	if (ipc_checkid(out, id)) {
-		ipc_unlock(out);
-		return ERR_PTR(-EIDRM);
-	}
-
-	return out;
-}
-
 struct kern_ipc_perm *ipc_lock_check(struct ipc_ids *ids, int id)
 {
 	struct kern_ipc_perm *out;
@@ -846,7 +787,7 @@ struct kern_ipc_perm *ipcctl_pre_down(struct ipc_ids *ids, int id, int cmd,
 	int err;
 
 	down_write(&ids->rw_mutex);
-	ipcp = ipc_lock_check_down(ids, id);
+	ipcp = ipc_lock_check(ids, id);
 	if (IS_ERR(ipcp)) {
 		err = PTR_ERR(ipcp);
 		goto out_up;