diff --git a/modutils/Config.in b/modutils/Config.in index c69e1b376..fb7fb2266 100644 --- a/modutils/Config.in +++ b/modutils/Config.in @@ -11,6 +11,20 @@ config DEPMOD help depmod generates modules.dep (FIXME: elaborate) +config FEATURE_DEPMOD_PRUNE_FANCY + bool "fancy dependency pruning" + default n + depends on DEPMOD + help + By default modules.dep contains all dependencies as listed by + the modules. + If you enable this option then we remove implied modules from + the dependencies. + This makes depmod somewhat bigger but generates a smaller + modules.dep file. + + If unsure, say N. + config INSMOD bool "insmod" default n diff --git a/modutils/depmod.c b/modutils/depmod.c index e061501f6..b0b09c235 100644 --- a/modutils/depmod.c +++ b/modutils/depmod.c @@ -10,15 +10,27 @@ #define _GNU_SOURCE #include #include /* uname() */ - +#if ENABLE_DEBUG +#include +#define dbg_assert assert +#else +#define dbg_assert(stuff) do {} while (0) +#endif /* * Theory of operation: * - iterate over all modules and record their full path * - iterate over all modules looking for "depends=" entries * for each depends, look through our list of full paths and emit if found */ + +typedef struct dep_lst_t { + char *name; + llist_t *dependencies; + struct dep_lst_t *next; +} dep_lst_t; + struct globals { - llist_t *lst; /* modules without their corresponding extension */ + dep_lst_t *lst; /* modules without their corresponding extension */ size_t moddir_base_len; /* length of the "-b basedir" */ }; #define G (*(struct globals*)&bb_common_bufsiz1) @@ -28,22 +40,28 @@ struct globals { static int fill_lst(const char *modulename, struct stat ATTRIBUTE_UNUSED *sb, void ATTRIBUTE_UNUSED *data, int ATTRIBUTE_UNUSED depth) { + /* We get a file here. If the file does not have ".ko" but an * intermittent dentry has, it's just their fault. */ - if (strrstr(modulename, ".ko") != NULL) - llist_add_to(&G.lst, xstrdup(modulename + G.moddir_base_len)); + if (strrstr(modulename, ".ko") != NULL) { + dep_lst_t *new = xzalloc(sizeof(dep_lst_t)); + new->name = xstrdup(modulename + G.moddir_base_len); + new->next = G.lst; + G.lst = new; + } return TRUE; } static int fileAction(const char *fname, struct stat *sb, - void *data, int ATTRIBUTE_UNUSED depth) + void ATTRIBUTE_UNUSED *data, int ATTRIBUTE_UNUSED depth) { size_t len = sb->st_size; void *the_module; char *ptr; int fd; char *depends, *deps; + dep_lst_t *this; if (strrstr(fname, ".ko") == NULL) /* not a module */ goto skip; @@ -61,40 +79,44 @@ static int fileAction(const char *fname, struct stat *sb, close(fd); if (the_module == MAP_FAILED) bb_perror_msg_and_die("mmap"); - ptr = the_module; - - fprintf((FILE*)data, "%s:", fname + G.moddir_base_len); + this = G.lst; + do { + if (!strcmp(fname + G.moddir_base_len, this->name)) + break; + this = this->next; + } while (this); + dbg_assert (this); //bb_info_msg("fname='%s'", fname + G.moddir_base_len); do { /* search for a 'd' */ ptr = memchr(ptr, 'd', len - (ptr - (char*)the_module)); if (ptr == NULL) /* no d left, done */ goto none; - if (strncmp(ptr, "depends=", sizeof("depends=")-1) == 0) + if (!strncmp(ptr, "depends=", sizeof("depends=")-1)) break; ++ptr; } while (1); deps = depends = xstrdup (ptr + sizeof("depends=")-1); //bb_info_msg(" depends='%s'", depends); while (deps) { - llist_t * _lst = G.lst; + dep_lst_t *all = G.lst; ptr = strsep(&deps, ","); - while (_lst) { + while (all) { /* Compare the recorded filenames ignoring ".ko*" at the end. */ - char *tmp = bb_get_last_path_component_nostrip(_lst->data); - if (strncmp(ptr, tmp, strrstr(tmp, ".ko") - tmp) == 0) + char *tmp = bb_get_last_path_component_nostrip(all->name); + if (!strncmp(ptr, tmp, MAX(strlen(ptr),strrstr(tmp, ".ko") - tmp))) break; /* found it */ - _lst = _lst->link; + all = all->next; } - if (_lst) { -//bb_info_msg("[%s] -> '%s'", (char*)ptr, _lst->data); - fprintf((FILE*)data, " %s", _lst->data); + if (all) { + dbg_assert(all->name); /* this cannot be empty */ +//bb_info_msg("[%s] -> '%s'", (char*)ptr, all->name); + llist_add_to_end(&this->dependencies, all->name); } } free(depends); - fprintf((FILE*)data, "\n"); none: munmap(the_module, sb->st_size); skip: @@ -115,11 +137,14 @@ int depmod_main(int ATTRIBUTE_UNUSED argc, char **argv) ARG_F = (1<<4), /* System.map that contains the symbols */ ARG_n = (1<<5) /* dry-run, print to stdout only */ }; + INIT_G(); getopt32(argv, "aAb:eF:n", &moddir_base, &system_map); argv += optind; - /* got a version to use? */ + /* If a version is provided, then that kernel version’s module directory + * is used, rather than the current kernel version (as returned by + * "uname -r"). */ if (*argv && (sscanf(*argv, "%d.%d.%d", &ret, &ret, &ret) == 3)) { moddir = concat_path_file(CONFIG_DEFAULT_MODULES_DIR, *argv++); } else { @@ -160,6 +185,9 @@ int depmod_main(int ATTRIBUTE_UNUSED argc, char **argv) else return EXIT_FAILURE; } +#if ENABLE_FEATURE_CLEAN_UP + else +#endif do { chp = option_mask32 & ARG_a ? moddir : *argv++; @@ -167,16 +195,74 @@ int depmod_main(int ATTRIBUTE_UNUSED argc, char **argv) ACTION_RECURSE, /* flags */ fileAction, /* file action */ NULL, /* dir action */ - (void*)filedes, /* user data */ + NULL, /* user data */ 0)) { /* depth */ ret = EXIT_FAILURE; } } while (!(option_mask32 & ARG_a) && *argv); + /* modprobe allegedly wants dependencies without duplicates, i.e. + * mod1: mod2 mod3 + * mod2: mod3 + * mod3: + * implies that mod1 directly depends on mod2 and _not_ mod3 as mod3 is + * already implicitely pulled in via mod2. This leaves us with: + * mod1: mod2 + * mod2: mod3 + * mod3: + */ + { + dep_lst_t *mods = G.lst; +#if ENABLE_FEATURE_DEPMOD_PRUNE_FANCY + while (mods) { + llist_t *deps = mods->dependencies; + while (deps) { + dep_lst_t *all = G.lst; + while (all) { + if (!strcmp(all->name, deps->data)) { + llist_t *implied = all->dependencies; + while (implied) { + /* erm, nicer would be to just + * llist_unlink(&mods->dependencies, implied) */ + llist_t *prune = mods->dependencies; + while (prune) { + if (!strcmp(implied->data, prune->data)) + break; + prune = prune->link; + } +//if (prune) bb_info_msg("[%s] '%s' implies '%s', removing", mods->name, all->name, implied->data); + llist_unlink(&mods->dependencies, prune); + implied = implied->link; + } + } + all = all->next; + } + deps = deps->link; + } + mods = mods->next; + } + + mods = G.lst; +#endif + /* Finally print them. */ + while (mods) { + fprintf(filedes, "%s:", mods->name); + while (mods->dependencies) + fprintf(filedes, " %s", (char*)llist_pop(&mods->dependencies)); + fprintf(filedes, "\n"); + mods = mods->next; + } + } + if (ENABLE_FEATURE_CLEAN_UP) { fclose_if_not_stdin(filedes); - llist_free(G.lst, free); free(moddir); + while (G.lst) { + dep_lst_t *old = G.lst; + G.lst = G.lst->next; + free(old->name); + free(old); + } } return ret; }