summaryrefslogtreecommitdiffstats
path: root/Documentation/userspace-api/netlink/specs.rst
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/userspace-api/netlink/specs.rst')
-rw-r--r--Documentation/userspace-api/netlink/specs.rst23
1 files changed, 16 insertions, 7 deletions
diff --git a/Documentation/userspace-api/netlink/specs.rst b/Documentation/userspace-api/netlink/specs.rst
index cc4e243099..c1b9516491 100644
--- a/Documentation/userspace-api/netlink/specs.rst
+++ b/Documentation/userspace-api/netlink/specs.rst
@@ -86,11 +86,6 @@ name
Name of the family. Name identifies the family in a unique way, since
the Family IDs are allocated dynamically.
-version
-~~~~~~~
-
-Generic Netlink family version, default is 1.
-
protocol
~~~~~~~~
@@ -408,10 +403,21 @@ This section describes the attribute types supported by the ``genetlink``
compatibility level. Refer to documentation of different levels for additional
attribute types.
-Scalar integer types
+Common integer types
--------------------
-Fixed-width integer types:
+``sint`` and ``uint`` represent signed and unsigned 64 bit integers.
+If the value can fit on 32 bits only 32 bits are carried in netlink
+messages, otherwise full 64 bits are carried. Note that the payload
+is only aligned to 4B, so the full 64 bit value may be unaligned!
+
+Common integer types should be preferred over fix-width types in majority
+of cases.
+
+Fix-width integer types
+-----------------------
+
+Fixed-width integer types include:
``u8``, ``u16``, ``u32``, ``u64``, ``s8``, ``s16``, ``s32``, ``s64``.
Note that types smaller than 32 bit should be avoided as using them
@@ -421,6 +427,9 @@ See :ref:`pad_type` for padding of 64 bit attributes.
The payload of the attribute is the integer in host order unless ``byte-order``
specifies otherwise.
+64 bit values are usually aligned by the kernel but it is recommended
+that the user space is able to deal with unaligned values.
+
.. _pad_type:
pad