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Diffstat (limited to 'net/rds/connection.c')
-rw-r--r--net/rds/connection.c54
1 files changed, 36 insertions, 18 deletions
diff --git a/net/rds/connection.c b/net/rds/connection.c
index d14445c4830..cc8b568c0c8 100644
--- a/net/rds/connection.c
+++ b/net/rds/connection.c
@@ -126,7 +126,7 @@ static struct rds_connection *__rds_conn_create(__be32 laddr, __be32 faddr,
struct rds_transport *trans, gfp_t gfp,
int is_outgoing)
{
- struct rds_connection *conn, *tmp, *parent = NULL;
+ struct rds_connection *conn, *parent = NULL;
struct hlist_head *head = rds_conn_bucket(laddr, faddr);
unsigned long flags;
int ret;
@@ -155,7 +155,6 @@ static struct rds_connection *__rds_conn_create(__be32 laddr, __be32 faddr,
}
INIT_HLIST_NODE(&conn->c_hash_node);
- conn->c_version = RDS_PROTOCOL_3_0;
conn->c_laddr = laddr;
conn->c_faddr = faddr;
spin_lock_init(&conn->c_lock);
@@ -211,26 +210,40 @@ static struct rds_connection *__rds_conn_create(__be32 laddr, __be32 faddr,
trans->t_name ? trans->t_name : "[unknown]",
is_outgoing ? "(outgoing)" : "");
+ /*
+ * Since we ran without holding the conn lock, someone could
+ * have created the same conn (either normal or passive) in the
+ * interim. We check while holding the lock. If we won, we complete
+ * init and return our conn. If we lost, we rollback and return the
+ * other one.
+ */
spin_lock_irqsave(&rds_conn_lock, flags);
- if (parent == NULL) {
- tmp = rds_conn_lookup(head, laddr, faddr, trans);
- if (tmp == NULL)
- hlist_add_head(&conn->c_hash_node, head);
- } else {
- tmp = parent->c_passive;
- if (!tmp)
+ if (parent) {
+ /* Creating passive conn */
+ if (parent->c_passive) {
+ trans->conn_free(conn->c_transport_data);
+ kmem_cache_free(rds_conn_slab, conn);
+ conn = parent->c_passive;
+ } else {
parent->c_passive = conn;
- }
-
- if (tmp) {
- trans->conn_free(conn->c_transport_data);
- kmem_cache_free(rds_conn_slab, conn);
- conn = tmp;
+ rds_cong_add_conn(conn);
+ rds_conn_count++;
+ }
} else {
- rds_cong_add_conn(conn);
- rds_conn_count++;
+ /* Creating normal conn */
+ struct rds_connection *found;
+
+ found = rds_conn_lookup(head, laddr, faddr, trans);
+ if (found) {
+ trans->conn_free(conn->c_transport_data);
+ kmem_cache_free(rds_conn_slab, conn);
+ conn = found;
+ } else {
+ hlist_add_head(&conn->c_hash_node, head);
+ rds_cong_add_conn(conn);
+ rds_conn_count++;
+ }
}
-
spin_unlock_irqrestore(&rds_conn_lock, flags);
out:
@@ -242,12 +255,14 @@ struct rds_connection *rds_conn_create(__be32 laddr, __be32 faddr,
{
return __rds_conn_create(laddr, faddr, trans, gfp, 0);
}
+EXPORT_SYMBOL_GPL(rds_conn_create);
struct rds_connection *rds_conn_create_outgoing(__be32 laddr, __be32 faddr,
struct rds_transport *trans, gfp_t gfp)
{
return __rds_conn_create(laddr, faddr, trans, gfp, 1);
}
+EXPORT_SYMBOL_GPL(rds_conn_create_outgoing);
void rds_conn_destroy(struct rds_connection *conn)
{
@@ -290,6 +305,7 @@ void rds_conn_destroy(struct rds_connection *conn)
rds_conn_count--;
}
+EXPORT_SYMBOL_GPL(rds_conn_destroy);
static void rds_conn_message_info(struct socket *sock, unsigned int len,
struct rds_info_iterator *iter,
@@ -393,6 +409,7 @@ void rds_for_each_conn_info(struct socket *sock, unsigned int len,
spin_unlock_irqrestore(&rds_conn_lock, flags);
}
+EXPORT_SYMBOL_GPL(rds_for_each_conn_info);
static int rds_conn_info_visitor(struct rds_connection *conn,
void *buffer)
@@ -468,6 +485,7 @@ void rds_conn_drop(struct rds_connection *conn)
atomic_set(&conn->c_state, RDS_CONN_ERROR);
queue_work(rds_wq, &conn->c_down_w);
}
+EXPORT_SYMBOL_GPL(rds_conn_drop);
/*
* An error occurred on the connection