Re: [PATCH 4/6] modpost: add support for generating namespace dependencies.

[Jessica Yu]

+++ Martijn Coenen [16/07/18 14:21 +0200]:
> This patch adds an option to modpost to generate a .ns_deps file per
> module, containing the namespace depedencies for that module.
>
> This file can subsequently be used by other tools to automatically add
> newly introduced namespaces to the modules that require them, saving a
> lot of manual work.
>
> Signed-off-by: Martijn Coenen <maco@xxxxxxxxxxx>

Regarding modpost, I think it may also be helpful to additionally
output the namespace an exported symbol belongs to (if any) in the
Module.symvers file.

> ---
> scripts/mod/modpost.c | 58 +++++++++++++++++++++++++++++++++++++++----
> scripts/mod/modpost.h |  2 ++
> 2 files changed, 55 insertions(+), 5 deletions(-)
>
> diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
> index a56a8461a96a..be33d60d5527 100644
> --- a/scripts/mod/modpost.c
> +++ b/scripts/mod/modpost.c
> @@ -39,6 +39,8 @@ static int sec_mismatch_verbose = 1;
> static int sec_mismatch_fatal = 0;
> /* ignore missing files */
> static int ignore_missing_files;
> +/* Write namespace dependencies */
> +static int write_ns_deps;
>
> enum export {
> 	export_plain,      export_unused,     export_gpl,
> @@ -2151,10 +2153,15 @@ static void check_exports(struct module *mod)
> 		else
> 			basename = mod->name;
>
> -		if (exp->ns && !module_imports_namespace(mod, exp->ns)) {
> -			warn("module %s uses symbol %s from namespace %s, "
> -			     "but does not import it.\n",
> -			     basename, exp->name, exp->ns);
> +		if (exp->ns) {
> +			add_namespace(&mod->required_namespaces, exp->ns);
> +
> +			if (!write_ns_deps &&
> +			    !module_imports_namespace(mod, exp->ns)) {
> +				warn("module %s uses symbol %s from namespace "
> +				     "%s, but does not import it.\n",
> +				     basename, exp->name, exp->ns);
> +			}
> 		}
>
> 		if (!mod->gpl_compatible)
> @@ -2457,6 +2464,38 @@ static void write_dump(const char *fname)
> 	free(buf.p);
> }
>
> +static void write_ns_deps_files(void)
> +{
> +	struct module *mod;
> +	struct namespace_list *ns;
> +	struct buffer ns_deps_buf = { };
> +
> +	for (mod = modules; mod; mod = mod->next) {
> +		char fname[PATH_MAX];
> +		const char *basename;
> +
> +		if (mod->skip)
> +			continue;
> +
> +		ns_deps_buf.pos = 0;
> +
> +		for (ns = mod->required_namespaces; ns; ns = ns->next)
> +			buf_printf(&ns_deps_buf, "%s\n", ns->namespace);
> +
> +		if (ns_deps_buf.pos == 0)
> +			continue;
> +
> +		basename = strrchr(mod->name, '/');
> +		if (basename)
> +			basename++;
> +		else
> +			basename = mod->name;
> +
> +		sprintf(fname, ".tmp_versions/%s.ns_deps", basename);
> +		write_if_changed(&ns_deps_buf, fname);
> +	}
> +}
> +
> struct ext_sym_list {
> 	struct ext_sym_list *next;
> 	const char *file;
> @@ -2473,7 +2512,7 @@ int main(int argc, char **argv)
> 	struct ext_sym_list *extsym_iter;
> 	struct ext_sym_list *extsym_start = NULL;
>
> -	while ((opt = getopt(argc, argv, "i:I:e:mnsST:o:awM:K:E")) != -1) {
> +	while ((opt = getopt(argc, argv, "i:I:e:mnsST:o:awM:K:Ed")) != -1) {
> 		switch (opt) {
> 		case 'i':
> 			kernel_read = optarg;
> @@ -2517,6 +2556,9 @@ int main(int argc, char **argv)
> 		case 'E':
> 			sec_mismatch_fatal = 1;
> 			break;
> +		case 'd':
> +			write_ns_deps = 1;
> +			break;
> 		default:
> 			exit(1);
> 		}
> @@ -2545,6 +2587,12 @@ int main(int argc, char **argv)
> 		check_exports(mod);
> 	}
>
> +	if (write_ns_deps) {
> +		/* Just write namespace dependencies and exit */
> +		write_ns_deps_files();
> +		return 0;
> +	}
> +
> 	err = 0;
>
> 	for (mod = modules; mod; mod = mod->next) {
> diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h
> index 9626bf3e7424..92a926d375d2 100644
> --- a/scripts/mod/modpost.h
> +++ b/scripts/mod/modpost.h
> @@ -126,6 +126,8 @@ struct module {
> 	struct buffer dev_table_buf;
> 	char	     srcversion[25];
> 	int is_dot_o;
> +	// Required namespace dependencies
> +	struct namespace_list *required_namespaces;
> 	// Actual imported namespaces
> 	struct namespace_list *imported_namespaces;
> };
> --
> 2.18.0.203.gfac676dfb9-goog