This is similar to modules.builtin, and constructed in a similar way to the way that used to be built before commit 8b41fc4454e36fbfdbb23f940d023d4dece2de29, via tristate.conf inclusion and recursive concatenation up the tree. Unlike modules.builtin, modules_thick.builtin givs the names of the object files that make up modules that are comprised of more than one object file, using a syntax similar to that of makefiles, e.g.: crypto/crypto.o: crypto/api.o crypto/cipher.o crypto/compress.o crypto/memneq.o crypto/crypto_algapi.o: crypto/algapi.o crypto/proc.o crypto/scatterwalk.o crypto/aead.o: crypto/geniv.o: (where the latter two are single-file modules). An upcoming commit will use this mapping to populate /proc/kallmodsyms. A parser is included that yields a stram of (module, objfile name[]) mappings: it's a bit baroque, but then parsing text files in C is quite painful, and I'd rather put the complexity in here than in its callers. The parser is not built in this commit, nor does it have any callers yet; nor is any rule added that causes modules_thick.builtin to actually be constructed. (Again, see a later commit for that.) I am not wedded to the approach used to construct this file, but I don't see any other way to do it despite spending a week or so trying to tie it into Kbuild without using a separate Makefile.modbuiltin: unlike the names of builtin modules (which are also recorded in the source files themseves via MODULE_*() macros) the mapping from object file name to built-in module name is not recorded anywhere but in the makefiles themselves, so we have to at least reparse them with something to indicate the builtin-ness of each module (i.e., tristate.conf) if we are to figure out which modules are built-in and which are not. Signed-off-by: Nick Alcock <nick.alcock@xxxxxxxxxx> Reviewed-by: Kris Van Hees <kris.van.hees@xxxxxxxxxx> --- .gitignore | 1 + Documentation/dontdiff | 1 + Makefile | 19 +++- scripts/Kbuild.include | 6 ++ scripts/Makefile.modbuiltin | 56 ++++++++++ scripts/modules_thick.c | 200 ++++++++++++++++++++++++++++++++++++ scripts/modules_thick.h | 48 +++++++++ 7 files changed, 330 insertions(+), 1 deletion(-) create mode 100644 scripts/Makefile.modbuiltin create mode 100644 scripts/modules_thick.c create mode 100644 scripts/modules_thick.h diff --git a/.gitignore b/.gitignore index 7afd412dadd2..b49cd96f587a 100644 --- a/.gitignore +++ b/.gitignore @@ -49,6 +49,7 @@ *.zst Module.symvers modules.order +modules_thick.builtin # # Top-level generic files diff --git a/Documentation/dontdiff b/Documentation/dontdiff index 910b30a2a7d9..6a78988547d0 100644 --- a/Documentation/dontdiff +++ b/Documentation/dontdiff @@ -183,6 +183,7 @@ modules.builtin modules.builtin.modinfo modules.nsdeps modules.order +modules_thick.builtin modversions.h* nconf nconf-cfg diff --git a/Makefile b/Makefile index 199b6f388484..5e823fe8390f 100644 --- a/Makefile +++ b/Makefile @@ -1470,6 +1470,23 @@ __modinst_pre: endif # CONFIG_MODULES +# modules_thick.builtin maps from kernel modules (or rather the object file +# names they would have had had they not been built in) to their constituent +# object files: we can use this to determine which modules any given object +# file is part of. (We cannot eliminate the slight redundancy here without +# double-expansion.) + +modthickbuiltin-files := $(addsuffix /modules_thick.builtin, $(build-dirs)) + +modules_thick.builtin: $(modthickbuiltin-files) + $(Q)$(AWK) '!x[$$0]++' $(addsuffix /$@, $(build-dirs)) > $@ + +# tristate.conf is not included from this Makefile. Add it as a prerequisite +# here to make it self-healing in case somebody accidentally removes it. +$(modthickbuiltin-files): include/config/tristate.conf + $(Q)$(MAKE) $(modbuiltin)=$(patsubst %/modules_thick.builtin,%,$@) builtin-file=modules_thick.builtin + + ### # Cleaning is done on three levels. # make clean Delete most generated files @@ -1849,7 +1866,7 @@ clean: $(clean-dirs) -o -name '*.lex.c' -o -name '*.tab.[ch]' \ -o -name '*.asn1.[ch]' \ -o -name '*.symtypes' -o -name 'modules.order' \ - -o -name '.tmp_*.o.*' \ + -o -name '.tmp_*.o.*' -o -name modules_thick.builtin \ -o -name '*.c.[012]*.*' \ -o -name '*.ll' \ -o -name '*.gcno' \ diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index 3514c2149e9d..167bbbd5fdf5 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -74,6 +74,12 @@ endef # $(Q)$(MAKE) $(build)=dir build := -f $(srctree)/scripts/Makefile.build obj +### +# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.modbuiltin obj= +# Usage: +# $(Q)$(MAKE) $(modbuiltin)=dir +modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj + ### # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj= # Usage: diff --git a/scripts/Makefile.modbuiltin b/scripts/Makefile.modbuiltin new file mode 100644 index 000000000000..a27b692ea795 --- /dev/null +++ b/scripts/Makefile.modbuiltin @@ -0,0 +1,56 @@ +# SPDX-License-Identifier: GPL-2.0 +# ========================================================================== +# Generating modules_thick.builtin +# ========================================================================== + +src := $(obj) + +PHONY := __modbuiltin +__modbuiltin: + +include include/config/auto.conf +# tristate.conf sets tristate variables to uppercase 'Y' or 'M' +# That way, we get the list of built-in modules in obj-Y +include include/config/tristate.conf + +include scripts/Kbuild.include + +ifdef building_out_of_srctree +# Create output directory if not already present +_dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj)) +endif + +# The filename Kbuild has precedence over Makefile +kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src)) +kbuild-file := $(if $(wildcard $(kbuild-dir)/Kbuild),$(kbuild-dir)/Kbuild,$(kbuild-dir)/Makefile) +include $(kbuild-file) + +include scripts/Makefile.lib + +modthickbuiltin-subdirs := $(patsubst %,%/modules_thick.builtin, $(subdir-ym)) +modthickbuiltin-target := $(obj)/modules_thick.builtin + +__modbuiltin: $(obj)/$(builtin-file) $(subdir-ym) + @: + +$(modthickbuiltin-target): $(subdir-ym) FORCE + $(Q) rm -f $@ + $(Q) $(foreach mod-o, $(filter %.o,$(obj-Y)),\ + printf "%s:" $(addprefix $(obj)/,$(mod-o)) >> $@; \ + printf " %s" $(sort $(strip $(addprefix $(obj)/,$($(mod-o:.o=-objs)) \ + $($(mod-o:.o=-y)) $($(mod-o:.o=-Y))))) >> $@; \ + printf "\n" >> $@; ) \ + cat /dev/null $(modthickbuiltin-subdirs) >> $@; + +PHONY += FORCE + +FORCE: + +# Descending +# --------------------------------------------------------------------------- + +PHONY += $(subdir-ym) +$(subdir-ym): + $(Q)$(MAKE) $(modbuiltin)=$@ builtin-file=$(builtin-file) + +.PHONY: $(PHONY) diff --git a/scripts/modules_thick.c b/scripts/modules_thick.c new file mode 100644 index 000000000000..9a15e99c1330 --- /dev/null +++ b/scripts/modules_thick.c @@ -0,0 +1,200 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * A simple modules_thick reader. + * + * (C) 2014, 2021 Oracle, Inc. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "modules_thick.h" + +/* + * Read a modules_thick.builtin file and translate it into a stream of + * name / module-name pairs. + */ + +/* + * Construct a modules_thick.builtin iterator. + */ +struct modules_thick_iter * +modules_thick_iter_new(const char *modules_thick_file) +{ + struct modules_thick_iter *i; + + i = calloc(1, sizeof(struct modules_thick_iter)); + if (i == NULL) + return NULL; + + i->f = fopen(modules_thick_file, "r"); + + if (i->f == NULL) { + fprintf(stderr, "Cannot open builtin module file %s: %s\n", + modules_thick_file, strerror(errno)); + return NULL; + } + + return i; +} + +/* + * Iterate, returning a new null-terminated array of object file names, and a + * new dynamically-allocated module name. (The module name passed in is freed.) + * + * The array of object file names should be freed by the caller: the strings it + * points to are owned by the iterator, and should not be freed. + */ + +char ** __attribute__((__nonnull__)) +modules_thick_iter_next(struct modules_thick_iter *i, char **module_name) +{ + size_t npaths = 1; + char **module_paths; + char *last_slash; + char *last_dot; + char *trailing_linefeed; + char *object_name = i->line; + char *dash; + int composite = 0; + + /* + * Read in all module entries, computing the suffixless, pathless name + * of the module and building the next arrayful of object file names for + * return. + * + * Modules can consist of multiple files: in this case, the portion + * before the colon is the path to the module (as before): the portion + * after the colon is a space-separated list of files that should be + * considered part of this module. In this case, the portion before the + * name is an "object file" that does not actually exist: it is merged + * into built-in.a without ever being written out. + * + * All module names have - translated to _, to match what is done to the + * names of the same things when built as modules. + */ + + /* + * Reinvocation of exhausted iterator. Return NULL, once. + */ +retry: + if (getline(&i->line, &i->line_size, i->f) < 0) { + if (ferror(i->f)) { + fprintf(stderr, "Error reading from modules_thick file:" + " %s\n", strerror(errno)); + exit(1); + } + rewind(i->f); + return NULL; + } + + if (i->line[0] == '\0') + goto retry; + + /* + * Slice the line in two at the colon, if any. If there is anything + * past the ': ', this is a composite module. (We allow for no colon + * for robustness, even though one should always be present.) + */ + if (strchr(i->line, ':') != NULL) { + char *name_start; + + object_name = strchr(i->line, ':'); + *object_name = '\0'; + object_name++; + name_start = object_name + strspn(object_name, " \n"); + if (*name_start != '\0') { + composite = 1; + object_name = name_start; + } + } + + /* + * Figure out the module name. + */ + last_slash = strrchr(i->line, '/'); + last_slash = (!last_slash) ? i->line : + last_slash + 1; + free(*module_name); + *module_name = strdup(last_slash); + dash = *module_name; + + while (dash != NULL) { + dash = strchr(dash, '-'); + if (dash != NULL) + *dash = '_'; + } + + last_dot = strrchr(*module_name, '.'); + if (last_dot != NULL) + *last_dot = '\0'; + + trailing_linefeed = strchr(object_name, '\n'); + if (trailing_linefeed != NULL) + *trailing_linefeed = '\0'; + + /* + * Multifile separator? Object file names explicitly stated: + * slice them up and shuffle them in. + * + * The array size may be an overestimate if any object file + * names start or end with spaces (very unlikely) but cannot be + * an underestimate. (Check for it anyway.) + */ + if (composite) { + char *one_object; + + for (npaths = 0, one_object = object_name; + one_object != NULL; + npaths++, one_object = strchr(one_object + 1, ' ')); + } + + module_paths = malloc((npaths + 1) * sizeof(char *)); + if (!module_paths) { + fprintf(stderr, "%s: out of memory on module %s\n", __func__, + *module_name); + exit(1); + } + + if (composite) { + char *one_object; + size_t i = 0; + + while ((one_object = strsep(&object_name, " ")) != NULL) { + if (i >= npaths) { + fprintf(stderr, "%s: num_objs overflow on module " + "%s: this is a bug.\n", __func__, + *module_name); + exit(1); + } + + module_paths[i++] = one_object; + } + } else + module_paths[0] = i->line; /* untransformed module name */ + + module_paths[npaths] = NULL; + + return module_paths; +} + +/* + * Free an iterator. Can be called while iteration is underway, so even + * state that is freed at the end of iteration must be freed here too. + */ +void +modules_thick_iter_free(struct modules_thick_iter *i) +{ + if (i == NULL) + return; + fclose(i->f); + free(i->line); + free(i); +} diff --git a/scripts/modules_thick.h b/scripts/modules_thick.h new file mode 100644 index 000000000000..f5edcaf9550c --- /dev/null +++ b/scripts/modules_thick.h @@ -0,0 +1,48 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * A simple modules_thick reader. + * + * (C) 2014, 2021 Oracle, Inc. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#ifndef _LINUX_MODULES_THICK_H +#define _LINUX_MODULES_THICK_H + +#include <stdio.h> +#include <stddef.h> + +/* + * modules_thick.builtin iteration state. + */ +struct modules_thick_iter { + FILE *f; + char *line; + size_t line_size; +}; + +/* + * Construct a modules_thick.builtin iterator. + */ +struct modules_thick_iter * +modules_thick_iter_new(const char *modules_thick_file); + +/* + * Iterate, returning a new null-terminated array of object file names, and a + * new dynamically-allocated module name. (The module name passed in is freed.) + * + * The array of object file names should be freed by the caller: the strings it + * points to are owned by the iterator, and should not be freed. + */ + +char ** __attribute__((__nonnull__)) +modules_thick_iter_next(struct modules_thick_iter *i, char **module_name); + +void +modules_thick_iter_free(struct modules_thick_iter *i); + +#endif -- 2.35.0.260.gb82b153193.dirty