RDMA/rxe: Return errors for add index and key

Modify rxe_add_index() and rxe_add_key() to return an error if the index
or key is aleady present in the pool.  Currently they print a warning and
silently fail with bad consequences to the caller.

Link: https://lore.kernel.org/r/20210608042552.33275-3-rpearsonhpe@gmail.comSigned-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

drivers/infiniband/sw/rxe/rxe_pool.c

@@ -183,7 +183,7 @@ static u32 alloc_index(struct rxe_pool *pool)
 	return index + pool->index.min_index;
 }
 
-static void insert_index(struct rxe_pool *pool, struct rxe_pool_entry *new)
+static int rxe_insert_index(struct rxe_pool *pool, struct rxe_pool_entry *new)
 {
 	struct rb_node **link = &pool->index.tree.rb_node;
 	struct rb_node *parent = NULL;
@@ -195,7 +195,7 @@ static void insert_index(struct rxe_pool *pool, struct rxe_pool_entry *new)
 
 		if (elem->index == new->index) {
 			pr_warn("element already exists!\n");
-			goto out;
+			return -EINVAL;
 		}
 
 		if (elem->index > new->index)
@@ -206,11 +206,11 @@ static void insert_index(struct rxe_pool *pool, struct rxe_pool_entry *new)
 
 	rb_link_node(&new->index_node, parent, link);
 	rb_insert_color(&new->index_node, &pool->index.tree);
-out:
-	return;
+
+	return 0;
 }
 
-static void insert_key(struct rxe_pool *pool, struct rxe_pool_entry *new)
+static int rxe_insert_key(struct rxe_pool *pool, struct rxe_pool_entry *new)
 {
 	struct rb_node **link = &pool->key.tree.rb_node;
 	struct rb_node *parent = NULL;
@@ -226,7 +226,7 @@ static void insert_key(struct rxe_pool *pool, struct rxe_pool_entry *new)
 
 		if (cmp == 0) {
 			pr_warn("key already exists!\n");
-			goto out;
+			return -EINVAL;
 		}
 
 		if (cmp > 0)
@@ -237,26 +237,32 @@ static void insert_key(struct rxe_pool *pool, struct rxe_pool_entry *new)
 
 	rb_link_node(&new->key_node, parent, link);
 	rb_insert_color(&new->key_node, &pool->key.tree);
-out:
-	return;
+
+	return 0;
 }
 
-void __rxe_add_key_locked(struct rxe_pool_entry *elem, void *key)
+int __rxe_add_key_locked(struct rxe_pool_entry *elem, void *key)
 {
 	struct rxe_pool *pool = elem->pool;
+	int err;
 
 	memcpy((u8 *)elem + pool->key.key_offset, key, pool->key.key_size);
-	insert_key(pool, elem);
+	err = rxe_insert_key(pool, elem);
+
+	return err;
 }
 
-void __rxe_add_key(struct rxe_pool_entry *elem, void *key)
+int __rxe_add_key(struct rxe_pool_entry *elem, void *key)
 {
 	struct rxe_pool *pool = elem->pool;
 	unsigned long flags;
+	int err;
 
 	write_lock_irqsave(&pool->pool_lock, flags);
-	__rxe_add_key_locked(elem, key);
+	err = __rxe_add_key_locked(elem, key);
 	write_unlock_irqrestore(&pool->pool_lock, flags);
+
+	return err;
 }
 
 void __rxe_drop_key_locked(struct rxe_pool_entry *elem)
@@ -276,22 +282,28 @@ void __rxe_drop_key(struct rxe_pool_entry *elem)
 	write_unlock_irqrestore(&pool->pool_lock, flags);
 }
 
-void __rxe_add_index_locked(struct rxe_pool_entry *elem)
+int __rxe_add_index_locked(struct rxe_pool_entry *elem)
 {
 	struct rxe_pool *pool = elem->pool;
+	int err;
 
 	elem->index = alloc_index(pool);
-	insert_index(pool, elem);
+	err = rxe_insert_index(pool, elem);
+
+	return err;
 }
 
-void __rxe_add_index(struct rxe_pool_entry *elem)
+int __rxe_add_index(struct rxe_pool_entry *elem)
 {
 	struct rxe_pool *pool = elem->pool;
 	unsigned long flags;
+	int err;
 
 	write_lock_irqsave(&pool->pool_lock, flags);
-	__rxe_add_index_locked(elem);
+	err = __rxe_add_index_locked(elem);
 	write_unlock_irqrestore(&pool->pool_lock, flags);
+
+	return err;
 }
 
 void __rxe_drop_index_locked(struct rxe_pool_entry *elem)

drivers/infiniband/sw/rxe/rxe_pool.h

@@ -111,11 +111,11 @@ int __rxe_add_to_pool(struct rxe_pool *pool, struct rxe_pool_entry *elem);
 /* assign an index to an indexed object and insert object into
  *  pool's rb tree holding and not holding the pool_lock
  */
-void __rxe_add_index_locked(struct rxe_pool_entry *elem);
+int __rxe_add_index_locked(struct rxe_pool_entry *elem);
 
 #define rxe_add_index_locked(obj) __rxe_add_index_locked(&(obj)->pelem)
 
-void __rxe_add_index(struct rxe_pool_entry *elem);
+int __rxe_add_index(struct rxe_pool_entry *elem);
 
 #define rxe_add_index(obj) __rxe_add_index(&(obj)->pelem)
 
@@ -133,11 +133,11 @@ void __rxe_drop_index(struct rxe_pool_entry *elem);
 /* assign a key to a keyed object and insert object into
  * pool's rb tree holding and not holding pool_lock
  */
-void __rxe_add_key_locked(struct rxe_pool_entry *elem, void *key);
+int __rxe_add_key_locked(struct rxe_pool_entry *elem, void *key);
 
 #define rxe_add_key_locked(obj, key) __rxe_add_key_locked(&(obj)->pelem, key)
 
-void __rxe_add_key(struct rxe_pool_entry *elem, void *key);
+int __rxe_add_key(struct rxe_pool_entry *elem, void *key);
 
 #define rxe_add_key(obj, key) __rxe_add_key(&(obj)->pelem, key)