Commit 4e9806a8 authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

tools: ynl-gen: support weird sub-message formats 



TC uses all possible sub-message formats:
 - nested attrs
 - fixed headers + nested attrs
 - fixed headers
 - empty

Nested attrs are already supported for rt-link. Add support
for remaining 3. The empty and fixed headers ones are fairly
trivial, we can fake a Binary or Flags type instead of a Nest.

For fixed headers + nest we need to teach nest parsing and
nest put to handle fixed headers.

Reviewed-by: default avatarDonald Hunter <donald.hunter@gmail.com>
Link: https://patch.msgid.link/20250520161916.413298-10-kuba@kernel.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 092b34b9

tools/net/ynl/lib/ynl-priv.h

+6 −2
Original line number Diff line number Diff line
@@ -213,11 +213,15 @@ static inline void *ynl_attr_data_end(const struct nlattr *attr) 
				     NLMSG_HDRLEN + fixed_hdr_sz); attr; \

	     (attr) = ynl_attr_next(ynl_nlmsg_end_addr(nlh), attr))



#define ynl_attr_for_each_nested(attr, outer)				\

#define ynl_attr_for_each_nested_off(attr, outer, offset)		\

	for ((attr) = ynl_attr_first(outer, outer->nla_len,		\

				     sizeof(struct nlattr)); attr;	\

				     sizeof(struct nlattr) + offset);	\

	     attr;							\

	     (attr) = ynl_attr_next(ynl_attr_data_end(outer), attr))



#define ynl_attr_for_each_nested(attr, outer)				\

	ynl_attr_for_each_nested_off(attr, outer, 0)



#define ynl_attr_for_each_payload(start, len, attr)			\

	for ((attr) = ynl_attr_first(start, len, 0); attr;		\

	     (attr) = ynl_attr_next(start + len, attr))

tools/net/ynl/pyynl/ynl_gen_c.py

+37 −11
Original line number Diff line number Diff line
@@ -1372,12 +1372,25 @@ class Family(SpecFamily): 


        attrs = []

        for name, fmt in submsg.formats.items():

            attrs.append({

            attr = {

                "name": name,

                "type": "nest",

                "parent-sub-message": spec,

                "nested-attributes": fmt['attribute-set']

            })

            }

            if 'attribute-set' in fmt:

                attr |= {

                    "type": "nest",

                    "nested-attributes": fmt['attribute-set'],

                }

                if 'fixed-header' in fmt:

                    attr |= { "fixed-header": fmt["fixed-header"] }

            elif 'fixed-header' in fmt:

                attr |= {

                    "type": "binary",

                    "struct": fmt["fixed-header"],

                }

            else:

                attr["type"] = "flag"

            attrs.append(attr)



        self.attr_sets[nested] = AttrSet(self, {

            "name": nested,
@@ -1921,8 +1934,11 @@ def put_typol_submsg(cw, struct): 


    i = 0

    for name, arg in struct.member_list():

        cw.p('[%d] = { .type = YNL_PT_SUBMSG, .name = "%s", .nest = &%s_nest, },' %

             (i, name, arg.nested_render_name))

        nest = ""

        if arg.type == 'nest':

            nest = f" .nest = &{arg.nested_render_name}_nest,"

        cw.p('[%d] = { .type = YNL_PT_SUBMSG, .name = "%s",%s },' %

             (i, name, nest))

        i += 1



    cw.block_end(line=';')
@@ -2032,6 +2048,11 @@ def put_req_nested(ri, struct): 
    if struct.submsg is None:

        local_vars.append('struct nlattr *nest;')

        init_lines.append("nest = ynl_attr_nest_start(nlh, attr_type);")

    if struct.fixed_header:

        local_vars.append('void *hdr;')

        struct_sz = f'sizeof({struct.fixed_header})'

        init_lines.append(f"hdr = ynl_nlmsg_put_extra_header(nlh, {struct_sz});")

        init_lines.append(f"memcpy(hdr, &obj->_hdr, {struct_sz});")



    has_anest = False

    has_count = False
@@ -2063,11 +2084,14 @@ def put_req_nested(ri, struct): 




def _multi_parse(ri, struct, init_lines, local_vars):

    if struct.fixed_header:

        local_vars += ['void *hdr;']

    if struct.nested:

        if struct.fixed_header:

            iter_line = f"ynl_attr_for_each_nested_off(attr, nested, sizeof({struct.fixed_header}))"

        else:

            iter_line = "ynl_attr_for_each_nested(attr, nested)"

    else:

        if struct.fixed_header:

            local_vars += ['void *hdr;']

        iter_line = "ynl_attr_for_each(attr, nlh, yarg->ys->family->hdr_len)"

        if ri.op.fixed_header != ri.family.fixed_header:

            if ri.family.is_classic():
@@ -2114,7 +2138,9 @@ def _multi_parse(ri, struct, init_lines, local_vars): 
        ri.cw.p(f'dst->{arg} = {arg};')



    if struct.fixed_header:

        if ri.family.is_classic():

        if struct.nested:

            ri.cw.p('hdr = ynl_attr_data(nested);')

        elif ri.family.is_classic():

            ri.cw.p('hdr = ynl_nlmsg_data(nlh);')

        else:

            ri.cw.p('hdr = ynl_nlmsg_data_offset(nlh, sizeof(struct genlmsghdr));')
@@ -2234,7 +2260,7 @@ def parse_rsp_submsg(ri, struct): 


        ri.cw.block_start(line=f'{kw} (!strcmp(sel, "{name}"))')

        get_lines, init_lines, _ = arg._attr_get(ri, var)

        for line in init_lines:

        for line in init_lines or []:

            ri.cw.p(line)

        for line in get_lines:

            ri.cw.p(line)