RDS: Fix locking in send on m_rs_lock

Do not nest m_rs_lock under c_lock

Disable interrupts in {rdma,atomic}_send_complete

Signed-off-by: Andy Grover <andy.grover@oracle.com>

diff --git a/net/rds/send.c b/net/rds/send.c
index aee58f931b69a2d4b2de899978d3c50d078508e5..725fb0419797863b5af6f27ff9b19e1b8bf9fc87 100644 (file)
--- a/net/rds/send.c
+++ b/net/rds/send.c
@@ -415,8 +415,9 @@ void rds_rdma_send_complete(struct rds_message *rm, int status)
        struct rds_sock *rs = NULL;
        struct rds_rdma_op *ro;
        struct rds_notifier *notifier;
+       unsigned long flags;
 
-       spin_lock(&rm->m_rs_lock);
+       spin_lock_irqsave(&rm->m_rs_lock, flags);
 
        ro = rm->m_rdma_op;
        if (test_bit(RDS_MSG_ON_SOCK, &rm->m_flags) &&
@@ -433,7 +434,7 @@ void rds_rdma_send_complete(struct rds_message *rm, int status)
                ro->r_notifier = NULL;
        }
 
-       spin_unlock(&rm->m_rs_lock);
+       spin_unlock_irqrestore(&rm->m_rs_lock, flags);
 
        if (rs) {
                rds_wake_sk_sleep(rs);
@@ -647,8 +648,8 @@ void rds_send_drop_to(struct rds_sock *rs, struct sockaddr_in *dest)
        list_for_each_entry(rm, &list, m_sock_item) {
 
                conn = rm->m_inc.i_conn;
-               spin_lock_irqsave(&conn->c_lock, flags);
 
+               spin_lock_irqsave(&conn->c_lock, flags);
                /*
                 * Maybe someone else beat us to removing rm from the conn.
                 * If we race with their flag update we'll get the lock and
@@ -658,23 +659,23 @@ void rds_send_drop_to(struct rds_sock *rs, struct sockaddr_in *dest)
                        spin_unlock_irqrestore(&conn->c_lock, flags);
                        continue;
                }
+               list_del_init(&rm->m_conn_item);
+               spin_unlock_irqrestore(&conn->c_lock, flags);
 
                /*
                 * Couldn't grab m_rs_lock in top loop (lock ordering),
                 * but we can now.
                 */
-               spin_lock(&rm->m_rs_lock);
+               spin_lock_irqsave(&rm->m_rs_lock, flags);
 
                spin_lock(&rs->rs_lock);
                __rds_rdma_send_complete(rs, rm, RDS_RDMA_CANCELED);
                spin_unlock(&rs->rs_lock);
 
                rm->m_rs = NULL;
-               spin_unlock(&rm->m_rs_lock);
+               spin_unlock_irqrestore(&rm->m_rs_lock, flags);
 
-               list_del_init(&rm->m_conn_item);
                rds_message_put(rm);
-               spin_unlock_irqrestore(&conn->c_lock, flags);
        }
 
        rds_wake_sk_sleep(rs);