diff --git a/Documentation/netlink/genetlink-legacy.yaml b/Documentation/netlink/genetlink-legacy.yaml index 5dc6f1c07a97..b33541a51d6b 100644 --- a/Documentation/netlink/genetlink-legacy.yaml +++ b/Documentation/netlink/genetlink-legacy.yaml @@ -218,6 +218,11 @@ properties: description: Max length for a string or a binary attribute. $ref: '#/$defs/len-or-define' sub-type: *attr-type + # Start genetlink-legacy + struct: + description: Name of the struct type used for the attribute. + type: string + # End genetlink-legacy # Make sure name-prefix does not appear in subsets (subsets inherit naming) dependencies: @@ -256,6 +261,14 @@ properties: async-enum: description: Name for the enum type with notifications/events. type: string + # Start genetlink-legacy + fixed-header: &fixed-header + description: | + Name of the structure defining the optional fixed-length protocol + header. This header is placed in a message after the netlink and + genetlink headers and before any attributes. + type: string + # End genetlink-legacy list: description: List of commands type: array @@ -288,6 +301,9 @@ properties: type: array items: enum: [ strict, dump ] + # Start genetlink-legacy + fixed-header: *fixed-header + # End genetlink-legacy do: &subop-type description: Main command handler. type: object diff --git a/Documentation/netlink/specs/ovs_datapath.yaml b/Documentation/netlink/specs/ovs_datapath.yaml new file mode 100644 index 000000000000..6d71db8c4416 --- /dev/null +++ b/Documentation/netlink/specs/ovs_datapath.yaml @@ -0,0 +1,153 @@ +# SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) + +name: ovs_datapath +version: 2 +protocol: genetlink-legacy + +doc: + OVS datapath configuration over generic netlink. + +definitions: + - + name: ovs-header + type: struct + members: + - + name: dp-ifindex + type: u32 + - + name: user-features + type: flags + entries: + - + name: unaligned + doc: Allow last Netlink attribute to be unaligned + - + name: vport-pids + doc: Allow datapath to associate multiple Netlink PIDs to each vport + - + name: tc-recirc-sharing + doc: Allow tc offload recirc sharing + - + name: dispatch-upcall-per-cpu + doc: Allow per-cpu dispatch of upcalls + - + name: datapath-stats + type: struct + members: + - + name: hit + type: u64 + - + name: missed + type: u64 + - + name: lost + type: u64 + - + name: flows + type: u64 + - + name: megaflow-stats + type: struct + members: + - + name: mask-hit + type: u64 + - + name: masks + type: u32 + - + name: padding + type: u32 + - + name: cache-hits + type: u64 + - + name: pad1 + type: u64 + +attribute-sets: + - + name: datapath + attributes: + - + name: name + type: string + - + name: upcall-pid + doc: upcall pid + type: u32 + - + name: stats + type: binary + struct: datapath-stats + - + name: megaflow-stats + type: binary + struct: megaflow-stats + - + name: user-features + type: u32 + enum: user-features + enum-as-flags: true + - + name: pad + type: unused + - + name: masks-cache-size + type: u32 + - + name: per-cpu-pids + type: binary + sub-type: u32 + +operations: + fixed-header: ovs-header + list: + - + name: dp-get + doc: Get / dump OVS data path configuration and state + value: 3 + attribute-set: datapath + do: &dp-get-op + request: + attributes: + - name + reply: + attributes: + - name + - upcall-pid + - stats + - megaflow-stats + - user-features + - masks-cache-size + - per-cpu-pids + dump: *dp-get-op + - + name: dp-new + doc: Create new OVS data path + value: 1 + attribute-set: datapath + do: + request: + attributes: + - dp-ifindex + - name + - upcall-pid + - user-features + - + name: dp-del + doc: Delete existing OVS data path + value: 2 + attribute-set: datapath + do: + request: + attributes: + - dp-ifindex + - name + +mcast-groups: + list: + - + name: ovs_datapath diff --git a/Documentation/netlink/specs/ovs_vport.yaml b/Documentation/netlink/specs/ovs_vport.yaml new file mode 100644 index 000000000000..8e55622ddf11 --- /dev/null +++ b/Documentation/netlink/specs/ovs_vport.yaml @@ -0,0 +1,139 @@ +# SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) + +name: ovs_vport +version: 2 +protocol: genetlink-legacy + +doc: + OVS vport configuration over generic netlink. + +definitions: + - + name: ovs-header + type: struct + members: + - + name: dp-ifindex + type: u32 + - + name: vport-type + type: enum + entries: [ unspec, netdev, internal, gre, vxlan, geneve ] + - + name: vport-stats + type: struct + members: + - + name: rx-packets + type: u64 + - + name: tx-packets + type: u64 + - + name: rx-bytes + type: u64 + - + name: tx-bytes + type: u64 + - + name: rx-errors + type: u64 + - + name: tx-errors + type: u64 + - + name: rx-dropped + type: u64 + - + name: tx-dropped + type: u64 + +attribute-sets: + - + name: vport-options + attributes: + - + name: dst-port + type: u32 + - + name: extension + type: u32 + - + name: upcall-stats + attributes: + - + name: success + type: u64 + value: 0 + - + name: fail + type: u64 + - + name: vport + attributes: + - + name: port-no + type: u32 + - + name: type + type: u32 + enum: vport-type + - + name: name + type: string + - + name: options + type: nest + nested-attributes: vport-options + - + name: upcall-pid + type: binary + sub-type: u32 + - + name: stats + type: binary + struct: vport-stats + - + name: pad + type: unused + - + name: ifindex + type: u32 + - + name: netnsid + type: u32 + - + name: upcall-stats + type: nest + nested-attributes: upcall-stats + +operations: + list: + - + name: vport-get + doc: Get / dump OVS vport configuration and state + value: 3 + attribute-set: vport + fixed-header: ovs-header + do: &vport-get-op + request: + attributes: + - dp-ifindex + - name + reply: &dev-all + attributes: + - dp-ifindex + - port-no + - type + - name + - upcall-pid + - stats + - ifindex + - netnsid + - upcall-stats + dump: *vport-get-op + +mcast-groups: + list: + - + name: ovs_vport diff --git a/Documentation/userspace-api/netlink/genetlink-legacy.rst b/Documentation/userspace-api/netlink/genetlink-legacy.rst index 3bf0bcdf21d8..802875a37a27 100644 --- a/Documentation/userspace-api/netlink/genetlink-legacy.rst +++ b/Documentation/userspace-api/netlink/genetlink-legacy.rst @@ -162,9 +162,91 @@ Other quirks (todo) Structures ---------- -Legacy families can define C structures both to be used as the contents -of an attribute and as a fixed message header. The plan is to define -the structs in ``definitions`` and link the appropriate attrs. +Legacy families can define C structures both to be used as the contents of +an attribute and as a fixed message header. Structures are defined in +``definitions`` and referenced in operations or attributes. Note that +structures defined in YAML are implicitly packed according to C +conventions. For example, the following struct is 4 bytes, not 6 bytes: + +.. code-block:: c + + struct { + u8 a; + u16 b; + u8 c; + } + +Any padding must be explicitly added and C-like languages should infer the +need for explicit padding from whether the members are naturally aligned. + +Here is the struct definition from above, declared in YAML: + +.. code-block:: yaml + + definitions: + - + name: message-header + type: struct + members: + - + name: a + type: u8 + - + name: b + type: u16 + - + name: c + type: u8 + +Fixed Headers +~~~~~~~~~~~~~ + +Fixed message headers can be added to operations using ``fixed-header``. +The default ``fixed-header`` can be set in ``operations`` and it can be set +or overridden for each operation. + +.. code-block:: yaml + + operations: + fixed-header: message-header + list: + - + name: get + fixed-header: custom-header + attribute-set: message-attrs + +Attributes +~~~~~~~~~~ + +A ``binary`` attribute can be interpreted as a C structure using a +``struct`` property with the name of the structure definition. The +``struct`` property implies ``sub-type: struct`` so it is not necessary to +specify a sub-type. + +.. code-block:: yaml + + attribute-sets: + - + name: stats-attrs + attributes: + - + name: stats + type: binary + struct: vport-stats + +C Arrays +-------- + +Legacy families also use ``binary`` attributes to encapsulate C arrays. The +``sub-type`` is used to identify the type of scalar to extract. + +.. code-block:: yaml + + attributes: + - + name: ports + type: binary + sub-type: u32 Multi-message DO ---------------- diff --git a/Documentation/userspace-api/netlink/specs.rst b/Documentation/userspace-api/netlink/specs.rst index a22442ba1d30..2e4acde890b7 100644 --- a/Documentation/userspace-api/netlink/specs.rst +++ b/Documentation/userspace-api/netlink/specs.rst @@ -254,6 +254,16 @@ rather than depend on what is specified in the spec file. The validation policy in the kernel is formed by combining the type definition (``type`` and ``nested-attributes``) and the ``checks``. +sub-type +~~~~~~~~ + +Legacy families have special ways of expressing arrays. ``sub-type`` can be +used to define the type of array members in case array members are not +fully defined as attributes (in a bona fide attribute space). For instance +a C array of u32 values can be specified with ``type: binary`` and +``sub-type: u32``. Binary types and legacy array formats are described in +more detail in :doc:`genetlink-legacy`. + operations ---------- diff --git a/tools/net/ynl/lib/nlspec.py b/tools/net/ynl/lib/nlspec.py index dba70100124a..06a906d74f0e 100644 --- a/tools/net/ynl/lib/nlspec.py +++ b/tools/net/ynl/lib/nlspec.py @@ -149,8 +149,11 @@ class SpecAttr(SpecElement): Represents a single attribute type within an attr space. Attributes: - value numerical ID when serialized - attr_set Attribute Set containing this attr + value numerical ID when serialized + attr_set Attribute Set containing this attr + is_multi bool, attr may repeat multiple times + struct_name string, name of struct definition + sub_type string, name of sub type """ def __init__(self, family, attr_set, yaml, value): super().__init__(family, yaml) @@ -158,6 +161,8 @@ class SpecAttr(SpecElement): self.value = value self.attr_set = attr_set self.is_multi = yaml.get('multi-attr', False) + self.struct_name = yaml.get('struct') + self.sub_type = yaml.get('sub-type') class SpecAttrSet(SpecElement): @@ -214,22 +219,61 @@ class SpecAttrSet(SpecElement): return self.attrs.items() +class SpecStructMember(SpecElement): + """Struct member attribute + + Represents a single struct member attribute. + + Attributes: + type string, type of the member attribute + """ + def __init__(self, family, yaml): + super().__init__(family, yaml) + self.type = yaml['type'] + + +class SpecStruct(SpecElement): + """Netlink struct type + + Represents a C struct definition. + + Attributes: + members ordered list of struct members + """ + def __init__(self, family, yaml): + super().__init__(family, yaml) + + self.members = [] + for member in yaml.get('members', []): + self.members.append(self.new_member(family, member)) + + def new_member(self, family, elem): + return SpecStructMember(family, elem) + + def __iter__(self): + yield from self.members + + def items(self): + return self.members.items() + + class SpecOperation(SpecElement): """Netlink Operation Information about a single Netlink operation. Attributes: - value numerical ID when serialized, None if req/rsp values differ + value numerical ID when serialized, None if req/rsp values differ - req_value numerical ID when serialized, user -> kernel - rsp_value numerical ID when serialized, user <- kernel - is_call bool, whether the operation is a call - is_async bool, whether the operation is a notification - is_resv bool, whether the operation does not exist (it's just a reserved ID) - attr_set attribute set name + req_value numerical ID when serialized, user -> kernel + rsp_value numerical ID when serialized, user <- kernel + is_call bool, whether the operation is a call + is_async bool, whether the operation is a notification + is_resv bool, whether the operation does not exist (it's just a reserved ID) + attr_set attribute set name + fixed_header string, optional name of fixed header struct - yaml raw spec as loaded from the spec file + yaml raw spec as loaded from the spec file """ def __init__(self, family, yaml, req_value, rsp_value): super().__init__(family, yaml) @@ -241,6 +285,7 @@ class SpecOperation(SpecElement): self.is_call = 'do' in yaml or 'dump' in yaml self.is_async = 'notify' in yaml or 'event' in yaml self.is_resv = not self.is_async and not self.is_call + self.fixed_header = self.yaml.get('fixed-header', family.fixed_header) # Added by resolve: self.attr_set = None @@ -281,6 +326,7 @@ class SpecFamily(SpecElement): msgs_by_value dict of all messages (indexed by name) ops dict of all valid requests / responses consts dict of all constants/enums + fixed_header string, optional name of family default fixed header struct """ def __init__(self, spec_path, schema_path=None): with open(spec_path, "r") as stream: @@ -344,6 +390,9 @@ class SpecFamily(SpecElement): def new_attr_set(self, elem): return SpecAttrSet(self, elem) + def new_struct(self, elem): + return SpecStruct(self, elem) + def new_operation(self, elem, req_val, rsp_val): return SpecOperation(self, elem, req_val, rsp_val) @@ -351,6 +400,7 @@ class SpecFamily(SpecElement): self._resolution_list.append(elem) def _dictify_ops_unified(self): + self.fixed_header = self.yaml['operations'].get('fixed-header') val = 1 for elem in self.yaml['operations']['list']: if 'value' in elem: @@ -362,6 +412,7 @@ class SpecFamily(SpecElement): self.msgs[op.name] = op def _dictify_ops_directional(self): + self.fixed_header = self.yaml['operations'].get('fixed-header') req_val = rsp_val = 1 for elem in self.yaml['operations']['list']: if 'notify' in elem: @@ -399,6 +450,8 @@ class SpecFamily(SpecElement): for elem in definitions: if elem['type'] == 'enum' or elem['type'] == 'flags': self.consts[elem['name']] = self.new_enum(elem) + elif elem['type'] == 'struct': + self.consts[elem['name']] = self.new_struct(elem) else: self.consts[elem['name']] = elem diff --git a/tools/net/ynl/lib/ynl.py b/tools/net/ynl/lib/ynl.py index 7eaf066b115e..ec40918152e1 100644 --- a/tools/net/ynl/lib/ynl.py +++ b/tools/net/ynl/lib/ynl.py @@ -68,6 +68,11 @@ class Netlink: class NlAttr: + type_formats = { 'u8' : ('B', 1), 's8' : ('b', 1), + 'u16': ('H', 2), 's16': ('h', 2), + 'u32': ('I', 4), 's32': ('i', 4), + 'u64': ('Q', 8), 's64': ('q', 8) } + def __init__(self, raw, offset): self._len, self._type = struct.unpack("HH", raw[offset:offset + 4]) self.type = self._type & ~Netlink.NLA_TYPE_MASK @@ -93,6 +98,21 @@ class NlAttr: def as_bin(self): return self.raw + def as_c_array(self, type): + format, _ = self.type_formats[type] + return list({ x[0] for x in struct.iter_unpack(format, self.raw) }) + + def as_struct(self, members): + value = dict() + offset = 0 + for m in members: + # TODO: handle non-scalar members + format, size = self.type_formats[m.type] + decoded = struct.unpack_from(format, self.raw, offset) + offset += size + value[m.name] = decoded[0] + return value + def __repr__(self): return f"[type:{self.type} len:{self._len}] {self.raw}" @@ -258,14 +278,22 @@ def _genl_load_families(): class GenlMsg: - def __init__(self, nl_msg): + def __init__(self, nl_msg, fixed_header_members=[]): self.nl = nl_msg self.hdr = nl_msg.raw[0:4] - self.raw = nl_msg.raw[4:] + offset = 4 self.genl_cmd, self.genl_version, _ = struct.unpack("BBH", self.hdr) + self.fixed_header_attrs = dict() + for m in fixed_header_members: + format, size = NlAttr.type_formats[m.type] + decoded = struct.unpack_from(format, nl_msg.raw, offset) + offset += size + self.fixed_header_attrs[m.name] = decoded[0] + + self.raw = nl_msg.raw[offset:] self.raw_attrs = NlAttrs(self.raw) def __repr__(self): @@ -367,6 +395,15 @@ class YnlFamily(SpecFamily): value = enum.entries_by_val[raw - i].name rsp[attr_spec['name']] = value + def _decode_binary(self, attr, attr_spec): + if attr_spec.struct_name: + decoded = attr.as_struct(self.consts[attr_spec.struct_name]) + elif attr_spec.sub_type: + decoded = attr.as_c_array(attr_spec.sub_type) + else: + decoded = attr.as_bin() + return decoded + def _decode(self, attrs, space): attr_space = self.attr_sets[space] rsp = dict() @@ -386,7 +423,7 @@ class YnlFamily(SpecFamily): elif attr_spec["type"] == 'string': decoded = attr.as_strz() elif attr_spec["type"] == 'binary': - decoded = attr.as_bin() + decoded = self._decode_binary(attr, attr_spec) elif attr_spec["type"] == 'flag': decoded = True else: @@ -480,6 +517,13 @@ class YnlFamily(SpecFamily): req_seq = random.randint(1024, 65535) msg = _genl_msg(self.family.family_id, nl_flags, op.req_value, 1, req_seq) + fixed_header_members = [] + if op.fixed_header: + fixed_header_members = self.consts[op.fixed_header].members + for m in fixed_header_members: + value = vals.pop(m.name) + format, _ = NlAttr.type_formats[m.type] + msg += struct.pack(format, value) for name, value in vals.items(): msg += self._add_attr(op.attr_set.name, name, value) msg = _genl_msg_finalize(msg) @@ -506,7 +550,7 @@ class YnlFamily(SpecFamily): done = True break - gm = GenlMsg(nl_msg) + gm = GenlMsg(nl_msg, fixed_header_members) # Check if this is a reply to our request if nl_msg.nl_seq != req_seq or gm.genl_cmd != op.rsp_value: if gm.genl_cmd in self.async_msg_ids: @@ -516,7 +560,8 @@ class YnlFamily(SpecFamily): print('Unexpected message: ' + repr(gm)) continue - rsp.append(self._decode(gm.raw_attrs, op.attr_set.name)) + rsp.append(self._decode(gm.raw_attrs, op.attr_set.name) + | gm.fixed_header_attrs) if not rsp: return None