RDMA/mlx5: Reorganize mlx5_ib_reg_user_mr()

This function handles an ODP and regular MR flow all mushed together, even
though the two flows are quite different. Split them into two dedicated
functions.

Link: https://lore.kernel.org/r/20201130075839.278575-5-leon@kernel.orgSigned-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

drivers/infiniband/hw/mlx5/mlx5_ib.h

@@ -1340,7 +1340,7 @@ void mlx5_odp_populate_xlt(void *xlt, size_t idx, size_t nentries,
 int mlx5_ib_advise_mr_prefetch(struct ib_pd *pd,
 			       enum ib_uverbs_advise_mr_advice advice,
 			       u32 flags, struct ib_sge *sg_list, u32 num_sge);
-int mlx5_ib_init_odp_mr(struct mlx5_ib_mr *mr, bool enable);
+int mlx5_ib_init_odp_mr(struct mlx5_ib_mr *mr);
 #else /* CONFIG_INFINIBAND_ON_DEMAND_PAGING */
 static inline void mlx5_ib_internal_fill_odp_caps(struct mlx5_ib_dev *dev)
 {
@@ -1362,7 +1362,7 @@ mlx5_ib_advise_mr_prefetch(struct ib_pd *pd,
 {
 	return -EOPNOTSUPP;
 }
-static inline int mlx5_ib_init_odp_mr(struct mlx5_ib_mr *mr, bool enable)
+static inline int mlx5_ib_init_odp_mr(struct mlx5_ib_mr *mr)
 {
 	return -EOPNOTSUPP;
 }

drivers/infiniband/hw/mlx5/odp.c

@@ -536,6 +536,10 @@ struct mlx5_ib_mr *mlx5_ib_alloc_implicit_mr(struct mlx5_ib_pd *pd,
 	struct mlx5_ib_mr *imr;
 	int err;
 
+	if (!mlx5_ib_can_load_pas_with_umr(dev,
+					   MLX5_IMR_MTT_ENTRIES * PAGE_SIZE))
+		return ERR_PTR(-EOPNOTSUPP);
+
 	umem_odp = ib_umem_odp_alloc_implicit(&dev->ib_dev, access_flags);
 	if (IS_ERR(umem_odp))
 		return ERR_CAST(umem_odp);
@@ -831,17 +835,13 @@ static int pagefault_mr(struct mlx5_ib_mr *mr, u64 io_virt, size_t bcnt,
 				     flags);
 }
 
-int mlx5_ib_init_odp_mr(struct mlx5_ib_mr *mr, bool enable)
+int mlx5_ib_init_odp_mr(struct mlx5_ib_mr *mr)
 {
-	u32 flags = MLX5_PF_FLAGS_SNAPSHOT;
 	int ret;
 
-	if (enable)
-		flags |= MLX5_PF_FLAGS_ENABLE;
-
-	ret = pagefault_real_mr(mr, to_ib_umem_odp(mr->umem),
-				mr->umem->address, mr->umem->length, NULL,
-				flags);
+	ret = pagefault_real_mr(mr, to_ib_umem_odp(mr->umem), mr->umem->address,
+				mr->umem->length, NULL,
+				MLX5_PF_FLAGS_SNAPSHOT | MLX5_PF_FLAGS_ENABLE);
 	return ret >= 0 ? 0 : ret;
 }