tools: ynl-gen: use names of constants in generated limits

YNL specs can use string expressions for limits, like s32-min
or u16-max. We convert all of those into their numeric values
when generating the code, which isn't always helpful. Try to
retain the string representations in the output. Any sort of
calculations still need the integers.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Joe Damato <jdamato@fastly.com>
Link: https://patch.msgid.link/20241010151248.2049755-1-kuba@kernel.org
[pabeni@redhat.com: regenerated netdev-genl-gen.c]
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net/core/netdev-genl-gen.c

@@ -14,16 +14,16 @@
 /* Integer value ranges */
 static const struct netlink_range_validation netdev_a_page_pool_id_range = {
 	.min	= 1ULL,
-	.max	= 4294967295ULL,
+	.max	= U32_MAX,
 };
 
 static const struct netlink_range_validation netdev_a_page_pool_ifindex_range = {
 	.min	= 1ULL,
-	.max	= 2147483647ULL,
+	.max	= S32_MAX,
 };
 
 static const struct netlink_range_validation netdev_a_napi_defer_hard_irqs_range = {
-	.max	= 2147483647ULL,
+	.max	= S32_MAX,
 };
 
 /* Common nested types */

tools/net/ynl/ynl-gen-c.py

@@ -80,11 +80,21 @@ class Type(SpecAttr):
         value = self.checks.get(limit, default)
         if value is None:
             return value
-        elif value in self.family.consts:
+        if isinstance(value, int):
+            return value
+        if value in self.family.consts:
+            raise Exception("Resolving family constants not implemented, yet")
+        return limit_to_number(value)
+
+    def get_limit_str(self, limit, default=None, suffix=''):
+        value = self.checks.get(limit, default)
+        if value is None:
+            return ''
+        if isinstance(value, int):
+            return str(value) + suffix
+        if value in self.family.consts:
             return c_upper(f"{self.family['name']}-{value}")
-        if not isinstance(value, int):
+        return c_upper(value)
-            value = limit_to_number(value)
-        return value
 
     def resolve(self):
         if 'name-prefix' in self.attr:
@@ -358,11 +368,11 @@ class TypeScalar(Type):
         elif 'full-range' in self.checks:
             return f"NLA_POLICY_FULL_RANGE({policy}, &{c_lower(self.enum_name)}_range)"
         elif 'range' in self.checks:
-            return f"NLA_POLICY_RANGE({policy}, {self.get_limit('min')}, {self.get_limit('max')})"
+            return f"NLA_POLICY_RANGE({policy}, {self.get_limit_str('min')}, {self.get_limit_str('max')})"
         elif 'min' in self.checks:
-            return f"NLA_POLICY_MIN({policy}, {self.get_limit('min')})"
+            return f"NLA_POLICY_MIN({policy}, {self.get_limit_str('min')})"
         elif 'max' in self.checks:
-            return f"NLA_POLICY_MAX({policy}, {self.get_limit('max')})"
+            return f"NLA_POLICY_MAX({policy}, {self.get_limit_str('max')})"
         return super()._attr_policy(policy)
 
     def _attr_typol(self):
@@ -413,11 +423,11 @@ class TypeString(Type):
 
     def _attr_policy(self, policy):
         if 'exact-len' in self.checks:
-            mem = 'NLA_POLICY_EXACT_LEN(' + str(self.get_limit('exact-len')) + ')'
+            mem = 'NLA_POLICY_EXACT_LEN(' + self.get_limit_str('exact-len') + ')'
         else:
             mem = '{ .type = ' + policy
             if 'max-len' in self.checks:
-                mem += ', .len = ' + str(self.get_limit('max-len'))
+                mem += ', .len = ' + self.get_limit_str('max-len')
             mem += ', }'
         return mem
 
@@ -476,9 +486,9 @@ class TypeBinary(Type):
         if len(self.checks) == 0:
             mem = '{ .type = NLA_BINARY, }'
         elif 'exact-len' in self.checks:
-            mem = 'NLA_POLICY_EXACT_LEN(' + str(self.get_limit('exact-len')) + ')'
+            mem = 'NLA_POLICY_EXACT_LEN(' + self.get_limit_str('exact-len') + ')'
         elif 'min-len' in self.checks:
-            mem = '{ .len = ' + str(self.get_limit('min-len')) + ', }'
+            mem = '{ .len = ' + self.get_limit_str('min-len') + ', }'
 
         return mem
 
@@ -2166,9 +2176,9 @@ def print_kernel_policy_ranges(family, cw):
             cw.block_start(line=f'static const struct netlink_range_validation{sign} {c_lower(attr.enum_name)}_range =')
             members = []
             if 'min' in attr.checks:
-                members.append(('min', str(attr.get_limit('min')) + suffix))
+                members.append(('min', attr.get_limit_str('min', suffix=suffix)))
             if 'max' in attr.checks:
-                members.append(('max', str(attr.get_limit('max')) + suffix))
+                members.append(('max', attr.get_limit_str('max', suffix=suffix)))
             cw.write_struct_init(members)
             cw.block_end(line=';')
             cw.nl()