[PATCH rdma-rc] RDMA/bnxt_re: Avoid exposing umdbr to userspace

The umdbr field in struct bnxt_re_db_region returns the raw
unmapped PCI BAR address of the doorbell region. Avoid sharing
this field to the userspace. Change this to a reserved field
and stop populating it, keeping the ABI layout and size
unchanged for existing binaries.

Fixes: 1234a9d8aebb ("RDMA/bnxt_re: Support doorbell extensions")
Signed-off-by: Sriharsha Basavapatna <[email protected]>
Reviewed-by: Selvin Xavier <[email protected]>
---
 drivers/infiniband/hw/bnxt_re/uapi.c | 6 ++----
 include/uapi/rdma/bnxt_re-abi.h      | 2 +-
 2 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/infiniband/hw/bnxt_re/uapi.c b/drivers/infiniband/hw/bnxt_re/uapi.c
index 263238a6e4cd..f278c4f70ff7 100644
--- a/drivers/infiniband/hw/bnxt_re/uapi.c
+++ b/drivers/infiniband/hw/bnxt_re/uapi.c
@@ -409,7 +409,6 @@ static int UVERBS_HANDLER(BNXT_RE_METHOD_DBR_ALLOC)(struct uverbs_attr_bundle *a
 	uobj->object = obj;
 	uverbs_finalize_uobj_create(attrs, BNXT_RE_ALLOC_DBR_HANDLE);
 
-	dbr.umdbr = dpi->umdbr;
 	dbr.dpi = dpi->dpi;
 	ret = uverbs_copy_to_struct_or_zero(attrs, BNXT_RE_ALLOC_DBR_ATTR,
 					    &dbr, sizeof(dbr));
@@ -472,7 +471,6 @@ static int UVERBS_HANDLER(BNXT_RE_METHOD_GET_DEFAULT_DBR)(struct uverbs_attr_bun
 		return PTR_ERR(ib_uctx);
 
 	uctx = container_of(ib_uctx, struct bnxt_re_ucontext, ib_uctx);
-	dpi.umdbr = uctx->dpi.umdbr;
 	dpi.dpi = uctx->dpi.dpi;
 
 	ret = uverbs_copy_to_struct_or_zero(attrs, BNXT_RE_DEFAULT_DBR_ATTR,
@@ -490,7 +488,7 @@ DECLARE_UVERBS_NAMED_METHOD(BNXT_RE_METHOD_DBR_ALLOC,
 					    UA_MANDATORY),
 			    UVERBS_ATTR_PTR_OUT(BNXT_RE_ALLOC_DBR_ATTR,
 						UVERBS_ATTR_STRUCT(struct bnxt_re_db_region,
-								   umdbr),
+								   reserved2),
 								   UA_MANDATORY),
 			    UVERBS_ATTR_PTR_OUT(BNXT_RE_ALLOC_DBR_OFFSET,
 						UVERBS_ATTR_TYPE(u64),
@@ -510,7 +508,7 @@ DECLARE_UVERBS_NAMED_OBJECT(BNXT_RE_OBJECT_DBR,
 DECLARE_UVERBS_NAMED_METHOD(BNXT_RE_METHOD_GET_DEFAULT_DBR,
 			    UVERBS_ATTR_PTR_OUT(BNXT_RE_DEFAULT_DBR_ATTR,
 						UVERBS_ATTR_STRUCT(struct bnxt_re_db_region,
-								   umdbr),
+								   reserved2),
 						UA_MANDATORY));
 
 DECLARE_UVERBS_GLOBAL_METHODS(BNXT_RE_OBJECT_DEFAULT_DBR,
diff --git a/include/uapi/rdma/bnxt_re-abi.h b/include/uapi/rdma/bnxt_re-abi.h
index a4599d7b736a..0a125c2a8cc4 100644
--- a/include/uapi/rdma/bnxt_re-abi.h
+++ b/include/uapi/rdma/bnxt_re-abi.h
@@ -247,7 +247,7 @@ struct bnxt_re_query_device_ex_resp {
 struct bnxt_re_db_region {
 	__u32 dpi;
 	__u32 reserved;
-	__aligned_u64 umdbr;
+	__aligned_u64 reserved2;
 };
 
 enum bnxt_re_obj_dbr_alloc_attrs {
-- 
2.51.2.636.ga99f379adf