mlx4_core: Implement SRQ object lookup from srqn

Expose a new API mlx4_srq_lookup() to retrive a SRQ based on its
number.  This API is needed in the mlx4_ib driver CQ polling logic,
when a work completion is associated with a XRC TGT QP.  Since a
target QP may redirect to more than one XRC SRQ, the srq field in the
QP has no usage and the real XRC SRQ need to be retrived using the
information from the XRCETH IB header which is placed in the HW CQE.

Signed-off-by: Shlomo Pongratz <shlomop@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

diff --git a/drivers/net/ethernet/mellanox/mlx4/srq.c b/drivers/net/ethernet/mellanox/mlx4/srq.c
index e329fe1f11b736d8e717880c7e6e7e092db2a14c..79fd269e2c54b3e0a043ab072a4e2b0f888e0088 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/srq.c
+++ b/drivers/net/ethernet/mellanox/mlx4/srq.c
@@ -298,3 +298,18 @@ void mlx4_cleanup_srq_table(struct mlx4_dev *dev)
                return;
        mlx4_bitmap_cleanup(&mlx4_priv(dev)->srq_table.bitmap);
 }
+
+struct mlx4_srq *mlx4_srq_lookup(struct mlx4_dev *dev, u32 srqn)
+{
+       struct mlx4_srq_table *srq_table = &mlx4_priv(dev)->srq_table;
+       struct mlx4_srq *srq;
+       unsigned long flags;
+
+       spin_lock_irqsave(&srq_table->lock, flags);
+       srq = radix_tree_lookup(&srq_table->tree,
+                               srqn & (dev->caps.num_srqs - 1));
+       spin_unlock_irqrestore(&srq_table->lock, flags);
+
+       return srq;
+}
+EXPORT_SYMBOL_GPL(mlx4_srq_lookup);

diff --git a/include/linux/mlx4/srq.h b/include/linux/mlx4/srq.h
index 799a0697a3835a751c4a63e02f82cf871d27c342..192e0f7784f2868e647eeb7b49abc15e7bab4639 100644 (file)
--- a/include/linux/mlx4/srq.h
+++ b/include/linux/mlx4/srq.h
@@ -39,4 +39,6 @@ struct mlx4_wqe_srq_next_seg {
        u32                     reserved2[3];
 };
 
+struct mlx4_srq *mlx4_srq_lookup(struct mlx4_dev *dev, u32 srqn);
+
 #endif /* MLX4_SRQ_H */