RDMA/core: Add optional access flags range

Define a range of access flags that are defined to be optional, both
uverbs and drivers should enable getting them and use if they are
applicable

This will be used, for example, for the relaxed ordering access flag which
unsupporting drivers can ignore.

Link: https://lore.kernel.org/r/1578506740-22188-7-git-send-email-yishaih@mellanox.comSigned-off-by: Michael Guralnik <michaelgur@mellanox.com>
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

include/rdma/ib_verbs.h

@@ -1419,7 +1419,9 @@ enum ib_access_flags {
 	IB_ACCESS_ON_DEMAND = IB_UVERBS_ACCESS_ON_DEMAND,
 	IB_ACCESS_HUGETLB = IB_UVERBS_ACCESS_HUGETLB,
 
-	IB_ACCESS_SUPPORTED = ((IB_ACCESS_HUGETLB << 1) - 1)
+	IB_ACCESS_OPTIONAL = IB_UVERBS_ACCESS_OPTIONAL_RANGE,
+	IB_ACCESS_SUPPORTED =
+		((IB_ACCESS_HUGETLB << 1) - 1) | IB_ACCESS_OPTIONAL,
 };
 
 /*

include/uapi/rdma/ib_user_ioctl_verbs.h

@@ -41,6 +41,9 @@
 #define RDMA_UAPI_PTR(_type, _name)	__aligned_u64 _name
 #endif
 
+#define IB_UVERBS_ACCESS_OPTIONAL_FIRST (1 << 20)
+#define IB_UVERBS_ACCESS_OPTIONAL_LAST (1 << 29)
+
 enum ib_uverbs_access_flags {
 	IB_UVERBS_ACCESS_LOCAL_WRITE = 1 << 0,
 	IB_UVERBS_ACCESS_REMOTE_WRITE = 1 << 1,
@@ -50,6 +53,10 @@ enum ib_uverbs_access_flags {
 	IB_UVERBS_ACCESS_ZERO_BASED = 1 << 5,
 	IB_UVERBS_ACCESS_ON_DEMAND = 1 << 6,
 	IB_UVERBS_ACCESS_HUGETLB = 1 << 7,
+
+	IB_UVERBS_ACCESS_OPTIONAL_RANGE =
+		((IB_UVERBS_ACCESS_OPTIONAL_LAST << 1) - 1) &
+		~(IB_UVERBS_ACCESS_OPTIONAL_FIRST - 1)
 };
 
 enum ib_uverbs_query_port_cap_flags {