X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=ipc%2Futil.c;h=be4230020a1f718c31b02012554600c710b928b9;hb=e350f8045f642dfc4c28a81c57d2103e1f7ceead;hp=ff3323ef8d8b4ea62f04306748e76cebd2f573e8;hpb=ba0e4ae88f0f71b42ad8734e0c371d321554f13b;p=firefly-linux-kernel-4.4.55.git

diff --git a/ipc/util.c b/ipc/util.c
index ff3323ef8d8b..be4230020a1f 100644
--- a/ipc/util.c
+++ b/ipc/util.c
@@ -467,10 +467,7 @@ void ipc_rcu_free(struct rcu_head *head)
 {
 	struct ipc_rcu *p = container_of(head, struct ipc_rcu, rcu);
 
-	if (is_vmalloc_addr(p))
-		vfree(p);
-	else
-		kfree(p);
+	kvfree(p);
 }
 
 /**
@@ -558,7 +555,7 @@ void ipc64_perm_to_ipc_perm(struct ipc64_perm *in, struct ipc_perm *out)
  * Call inside the RCU critical section.
  * The ipc object is *not* locked on exit.
  */
-struct kern_ipc_perm *ipc_obtain_object(struct ipc_ids *ids, int id)
+struct kern_ipc_perm *ipc_obtain_object_idr(struct ipc_ids *ids, int id)
 {
 	struct kern_ipc_perm *out;
 	int lid = ipcid_to_idx(id);
@@ -584,21 +581,24 @@ struct kern_ipc_perm *ipc_lock(struct ipc_ids *ids, int id)
 	struct kern_ipc_perm *out;
 
 	rcu_read_lock();
-	out = ipc_obtain_object(ids, id);
+	out = ipc_obtain_object_idr(ids, id);
 	if (IS_ERR(out))
-		goto err1;
+		goto err;
 
 	spin_lock(&out->lock);
 
-	/* ipc_rmid() may have already freed the ID while ipc_lock
-	 * was spinning: here verify that the structure is still valid
+	/*
+	 * ipc_rmid() may have already freed the ID while ipc_lock()
+	 * was spinning: here verify that the structure is still valid.
+	 * Upon races with RMID, return -EIDRM, thus indicating that
+	 * the ID points to a removed identifier.
 	 */
 	if (ipc_valid_object(out))
 		return out;
 
 	spin_unlock(&out->lock);
-	out = ERR_PTR(-EINVAL);
-err1:
+	out = ERR_PTR(-EIDRM);
+err:
 	rcu_read_unlock();
 	return out;
 }
@@ -608,7 +608,7 @@ err1:
  * @ids: ipc identifier set
  * @id: ipc id to look for
  *
- * Similar to ipc_obtain_object() but also checks
+ * Similar to ipc_obtain_object_idr() but also checks
  * the ipc object reference counter.
  *
  * Call inside the RCU critical section.
@@ -616,13 +616,13 @@ err1:
  */
 struct kern_ipc_perm *ipc_obtain_object_check(struct ipc_ids *ids, int id)
 {
-	struct kern_ipc_perm *out = ipc_obtain_object(ids, id);
+	struct kern_ipc_perm *out = ipc_obtain_object_idr(ids, id);
 
 	if (IS_ERR(out))
 		goto out;
 
 	if (ipc_checkid(out, id))
-		return ERR_PTR(-EIDRM);
+		return ERR_PTR(-EINVAL);
 out:
 	return out;
 }