RDS: Perform unmapping ops in stages

Previously, RDS would wait until the final send WR had completed
and then handle cleanup. With silent ops, we do not know
if an atomic, rdma, or data op will be last. This patch
handles any of these cases by keeping a pointer to the last
op in the message in m_last_op.

When the TX completion event fires, rds dispatches to per-op-type
cleanup functions, and then does whole-message cleanup, if the
last op equalled m_last_op.

This patch also moves towards having op-specific functions take
the op struct, instead of the overall rm struct.

rds_ib_connection has a pointer to keep track of a a partially-
completed data send operation. This patch changes it from an
rds_message pointer to the narrower rm_data_op pointer, and
modifies places that use this pointer as needed.

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

1 files changed, 3 insertions, 1 deletions

diff --git a/net/rds/rds.h b/net/rds/rds.h
index 23b921000e74..7291f006f364 100644
--- a/net/rds/rds.h
+++ b/net/rds/rds.h
@@ -308,6 +308,8 @@ struct rds_message {
         unsigned int            m_used_sgs;
         unsigned int            m_total_sgs;
 
+        void                    *m_final_op;
+
         struct {
                 struct rm_atomic_op {
                         int                     op_type;
@@ -421,7 +423,7 @@ struct rds_transport {
         int (*xmit_cong_map)(struct rds_connection *conn,
                              struct rds_cong_map *map, unsigned long offset);
         int (*xmit_rdma)(struct rds_connection *conn, struct rm_rdma_op *op);
-        int (*xmit_atomic)(struct rds_connection *conn, struct rds_message *rm);
+        int (*xmit_atomic)(struct rds_connection *conn, struct rm_atomic_op *op);
         int (*recv)(struct rds_connection *conn);
         int (*inc_copy_to_user)(struct rds_incoming *inc, struct iovec *iov,
                                 size_t size);