From fbf5df34a4dbcd09d433dd4f0916bf9b2ddb16de Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Sun, 10 May 2026 12:29:01 -0700 Subject: [PATCH] tools: ynl: add scope qualifier for definitions Using definitions in kernel policies is awkward right now. On one hand we want defines for max values and such. On the other we don't have a way of adding kernel-only defines. Adding unnecessary defines to uAPI is a bad idea, we won't be able to delete them. And when it comes to policy user space should just query it via the policy dump, not use hard coded defines. Add a "scope" property to definitions, which will let us tell the codegen that a definition is for kernel use only. Support following values: - uapi: render into the uAPI header (default, today's behavior) - kernel: render to kernel header only - user: same as kernel but for the user-side generated header Definitions may have a header property (definition is "external", provided by existing header). Extend the scope to headers, too. If definition has both scope and header properties we will only generate the includes in the right scope. Signed-off-by: Jakub Kicinski Link: https://patch.msgid.link/20260510192904.3987113-8-kuba@kernel.org Signed-off-by: Paolo Abeni --- Documentation/netlink/genetlink-c.yaml | 9 ++++++ Documentation/netlink/genetlink-legacy.yaml | 9 ++++++ Documentation/netlink/genetlink.yaml | 9 ++++++ Documentation/netlink/netlink-raw.yaml | 9 ++++++ tools/net/ynl/pyynl/ynl_gen_c.py | 31 +++++++++++++++++++-- 5 files changed, 65 insertions(+), 2 deletions(-) diff --git a/Documentation/netlink/genetlink-c.yaml b/Documentation/netlink/genetlink-c.yaml index 57f59fe23e3f..4ea31e8fc4d1 100644 --- a/Documentation/netlink/genetlink-c.yaml +++ b/Documentation/netlink/genetlink-c.yaml @@ -69,6 +69,15 @@ properties: header: description: For C-compatible languages, header which already defines this value. type: string + scope: + description: | + Visibility of this definition. "uapi" (default) renders into + the uAPI header, "kernel" renders into the kernel-side + generated header, "user" renders into the user-side + generated header. When combined with `header:`, the + definition is not rendered, and the named header is + included only by code matching the scope. + enum: [ uapi, kernel, user ] type: enum: [ const, enum, flags ] doc: diff --git a/Documentation/netlink/genetlink-legacy.yaml b/Documentation/netlink/genetlink-legacy.yaml index 66fb8653a344..f9c44747729a 100644 --- a/Documentation/netlink/genetlink-legacy.yaml +++ b/Documentation/netlink/genetlink-legacy.yaml @@ -83,6 +83,15 @@ properties: header: description: For C-compatible languages, header which already defines this value. type: string + scope: + description: | + Visibility of this definition. "uapi" (default) renders into + the uAPI header, "kernel" renders into the kernel-side + generated header, "user" renders into the user-side + generated header. When combined with `header:`, the + definition is not rendered, and the named header is + included only by code matching the scope. + enum: [ uapi, kernel, user ] type: enum: [ const, enum, flags, struct ] # Trim doc: diff --git a/Documentation/netlink/genetlink.yaml b/Documentation/netlink/genetlink.yaml index a1194d5d93fc..d3f3f3399ddf 100644 --- a/Documentation/netlink/genetlink.yaml +++ b/Documentation/netlink/genetlink.yaml @@ -55,6 +55,15 @@ properties: header: description: For C-compatible languages, header which already defines this value. type: string + scope: + description: | + Visibility of this definition. "uapi" (default) renders into + the uAPI header, "kernel" renders into the kernel-side + generated header, "user" renders into the user-side + generated header. When combined with `header:`, the + definition is not rendered, and the named header is + included only by code matching the scope. + enum: [ uapi, kernel, user ] type: enum: [ const, enum, flags ] doc: diff --git a/Documentation/netlink/netlink-raw.yaml b/Documentation/netlink/netlink-raw.yaml index dd98dda55bd0..4c436b59a34b 100644 --- a/Documentation/netlink/netlink-raw.yaml +++ b/Documentation/netlink/netlink-raw.yaml @@ -87,6 +87,15 @@ properties: header: description: For C-compatible languages, header which already defines this value. type: string + scope: + description: | + Visibility of this definition. "uapi" (default) renders into + the uAPI header, "kernel" renders into the kernel-side + generated header, "user" renders into the user-side + generated header. When combined with `header:`, the + definition is not rendered, and the named header is + included only by code matching the scope. + enum: [ uapi, kernel, user ] type: enum: [ const, enum, flags, struct ] # Trim doc: diff --git a/tools/net/ynl/pyynl/ynl_gen_c.py b/tools/net/ynl/pyynl/ynl_gen_c.py index 0e1e486c1185..cdc3646f2642 100755 --- a/tools/net/ynl/pyynl/ynl_gen_c.py +++ b/tools/net/ynl/pyynl/ynl_gen_c.py @@ -3212,6 +3212,8 @@ def render_uapi(family, cw): for const in family['definitions']: if const.get('header'): continue + if const.get('scope', 'uapi') != 'uapi': + continue if const['type'] != 'const': cw.writes_defines(defines) @@ -3339,6 +3341,25 @@ def render_uapi(family, cw): cw.p(f'#endif /* {hdr_prot} */') +def render_scoped_consts(family, cw, scope): + defines = [] + for const in family['definitions']: + if const['type'] != 'const': + continue + if const.get('header'): + continue + if const.get('scope') != scope: + continue + name_pfx = const.get('name-prefix', f"{family.ident_name}-") + defines.append([ + c_upper(family.get('c-define-name', + f"{name_pfx}{const['name']}")), + const['value']]) + if defines: + cw.writes_defines(defines) + cw.nl() + + def _render_user_ntf_entry(ri, op): if not ri.family.is_classic(): ri.cw.block_start(line=f"[{op.enum_name}] = ") @@ -3504,8 +3525,12 @@ def main(): cw.p('#include "ynl.h"') headers = [] for definition in parsed['definitions'] + parsed['attribute-sets']: - if 'header' in definition: - headers.append(definition['header']) + if 'header' not in definition: + continue + scope = definition.get('scope', 'uapi') + if scope != 'uapi' and scope != args.mode: + continue + headers.append(definition['header']) if args.mode == 'user': headers.append(parsed.uapi_header) seen_header = [] @@ -3522,6 +3547,7 @@ def main(): for one in args.user_header: cw.p(f'#include "{one}"') else: + render_scoped_consts(parsed, cw, 'user') cw.p('struct ynl_sock;') cw.nl() render_user_family(parsed, cw, True) @@ -3529,6 +3555,7 @@ def main(): if args.mode == "kernel": if args.header: + render_scoped_consts(parsed, cw, 'kernel') for _, struct in sorted(parsed.pure_nested_structs.items()): if struct.request: cw.p('/* Common nested types */')