On Thursday 05 March 2009 08:37:45 pm Timo Teräs wrote:
> Denys Vlasenko wrote:
> > I also renamed a few fields and variables here and there, added comments.
> > Please review/test current svn. The // comments are TODOs.
> >
> > For easy reference new modprobe.c is attached.
>
> > #define MODULE_FLAG_LOADED 0x0001
> > #define MODULE_FLAG_NEED_DEPS 0x0002
> > //Misnomer? Seems to mean "was seen in modules.dep":
>
> Not really. It gets set for all the modules we want to load. Those are:
> 1. the names implied on command line
> 2. the aliases defined for command line names
>
> So for only those entries we actually load and store in memory the
> modules.dep stuff.
Are you saying that name "MODULE_FLAG_EXISTS" is descriptive for
the above? I don't think so. Renaming...
> > struct globals {
> > llist_t *db; /* MEs of all modules ever seen (caching for speed) */
> > llist_t *probes; /* MEs of module(s) requested on cmdline */
> > llist_t *cmdline_mopts; /* strings. module options (from cmdline) */
> > int num_deps; /* what is this? */
>
> Number of module entries that we need to load the dependencies for still.
> E.g. initially set as explained above. For each entry found in modules.dep
> during initial pass, it's decremented.
>
> This way, after loading modules.dep once, we know if there are still
> "virtual" probe names. If there are, we load and parse the system alias
> file. We generally want to avoid this since it's very large, and alias
> matching uses fnmatch(). This same optimization is in module-init-tools
> too.
I am renaming it to num_unresolved_deps then.
> > p = config_open2(CONFIG_DEFAULT_DEPMOD_FILE, xfopen_for_read);
> > //Still true?
> > /* Modprobe does not work at all without modprobe.dep,
> > * even if the full module name is given. Returning error here
> > * was making us later confuse user with this message:
> > * "module /full/path/to/existing/file/module.ko not found".
> > * It's better to die immediately, with good message: */
> > // if (p == NULL)
> > // bb_perror_msg_and_die("can't open '%s'",
> > CONFIG_DEFAULT_DEPMOD_FILE);
>
> Ah. Yeah, this actually confliced. Apparently did not realize that
> I added the 'x' for xfopen_for_read. The check is no longer necessary.
Ah... yes I didn't notice that. Removing //commented code...
> > m = get_modentry(tokens[0]);
> > if (m == NULL)
> > continue;
> > //Can we skip it too if it is MODULE_FLAG_LOADED?
>
> Yes and no. Only if we are loading modules. If we are running with
> '-r' to remove all modules then we obviously need the dependencies
> even if it's loaded.
I am adding this then:
/* Optimization... */
if ((m->flags & MODULE_FLAG_LOADED)
&& !(option_mask32 & MODPROBE_OPT_REMOVE)
) {
continue;
}
> > /* First argument is module name, rest are parameters */
> > add_probe(argv[0]);
> > //TODO: looks like G.cmdline_mopts can contain either NULL or just one
> > string, not more?
> > //optimize it them
> > llist_add_to(&G.cmdline_mopts,
> > parse_cmdline_module_options(argv));
>
> Correct.
Trying to do something about it... Ok, replaced lists
or options with one string, should be more compact.
Hmm, ->aliases member is also misnamed.
It's not "aliases of this module", it's
"real names of this module which is an alias"! Great...
Please find new modprobe.c attached.
Lightly tested.
function old new delta
gather_options_str - 75 +75
config_file_action 388 413 +25
load_modules_dep 175 192 +17
add_probe 67 72 +5
modprobe_main 494 488 -6
gather_options 89 - -89
------------------------------------------------------------------------------
(add/remove: 1/1 grow/shrink: 3/1 up/down: 122/-95) Total: 27 bytes
--
vda
/* vi: set sw=4 ts=4: */
/*
* Modprobe written from scratch for BusyBox
*
* Copyright (c) 2008 Timo Teras <[email protected]>
* Copyright (c) 2008 Vladimir Dronnikov
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
#include "libbb.h"
#include "modutils.h"
#include <sys/utsname.h>
#include <fnmatch.h>
//#define DBG(...) bb_error_msg(__VA_ARGS__)
#define DBG(...) ((void)0)
#define MODULE_FLAG_LOADED 0x0001
#define MODULE_FLAG_NEED_DEPS 0x0002
/* "was seen in modules.dep": */
#define MODULE_FLAG_FOUND_IN_MODDEP 0x0004
#define MODULE_FLAG_BLACKLISTED 0x0008
struct module_entry { /* I'll call it ME. */
unsigned flags;
char *modname; /* stripped of /path/, .ext and s/-/_/g */
const char *probed_name; /* verbatim as seen on cmdline */
char *options; /* options from config files */
llist_t *realnames; /* strings. if this module is an alias, real module name is this one */
llist_t *deps; /* strings. modules we depend on */
};
#define MODPROBE_OPTS "acdlnrt:VC:" USE_FEATURE_MODPROBE_BLACKLIST("b")
enum {
MODPROBE_OPT_INSERT_ALL = (INSMOD_OPT_UNUSED << 0), /* a */
MODPROBE_OPT_DUMP_ONLY = (INSMOD_OPT_UNUSED << 1), /* c */
MODPROBE_OPT_D = (INSMOD_OPT_UNUSED << 2), /* d */
MODPROBE_OPT_LIST_ONLY = (INSMOD_OPT_UNUSED << 3), /* l */
MODPROBE_OPT_SHOW_ONLY = (INSMOD_OPT_UNUSED << 4), /* n */
MODPROBE_OPT_REMOVE = (INSMOD_OPT_UNUSED << 5), /* r */
MODPROBE_OPT_RESTRICT = (INSMOD_OPT_UNUSED << 6), /* t */
MODPROBE_OPT_VERONLY = (INSMOD_OPT_UNUSED << 7), /* V */
MODPROBE_OPT_CONFIGFILE = (INSMOD_OPT_UNUSED << 8), /* C */
MODPROBE_OPT_BLACKLIST = (INSMOD_OPT_UNUSED << 9) * ENABLE_FEATURE_MODPROBE_BLACKLIST,
};
struct globals {
llist_t *db; /* MEs of all modules ever seen (caching for speed) */
llist_t *probes; /* MEs of module(s) requested on cmdline */
char *cmdline_mopts; /* module options from cmdline */
int num_unresolved_deps;
/* bool. "Did we have 'symbol:FOO' requested on cmdline?" */
smallint need_symbols;
};
#define G (*(struct globals*)&bb_common_bufsiz1)
#define INIT_G() do { } while (0)
static int read_config(const char *path);
static char *gather_options_str(char *opts, const char *append)
{
/* Speed-optimized. We call gather_options_str many times. */
if (opts == NULL) {
opts = xstrdup(append);
} else {
int optlen = strlen(opts);
opts = xrealloc(opts, optlen + strlen(append) + 2);
sprintf(opts + optlen, " %s", append);
}
return opts;
}
static struct module_entry *helper_get_module(const char *module, int create)
{
char modname[MODULE_NAME_LEN];
struct module_entry *e;
llist_t *l;
filename2modname(module, modname);
for (l = G.db; l != NULL; l = l->link) {
e = (struct module_entry *) l->data;
if (strcmp(e->modname, modname) == 0)
return e;
}
if (!create)
return NULL;
e = xzalloc(sizeof(*e));
e->modname = xstrdup(modname);
llist_add_to(&G.db, e);
return e;
}
static struct module_entry *get_or_add_modentry(const char *module)
{
return helper_get_module(module, 1);
}
static struct module_entry *get_modentry(const char *module)
{
return helper_get_module(module, 0);
}
static void add_probe(const char *name)
{
struct module_entry *m;
m = get_or_add_modentry(name);
if (m->flags & MODULE_FLAG_LOADED) {
DBG("skipping %s, it is already loaded", name);
return;
}
m->probed_name = name;
m->flags |= MODULE_FLAG_NEED_DEPS;
llist_add_to_end(&G.probes, m);
G.num_unresolved_deps++;
if (ENABLE_FEATURE_MODUTILS_SYMBOLS
&& strncmp(m->modname, "symbol:", 7) == 0
) {
G.need_symbols = 1;
}
}
static int FAST_FUNC config_file_action(const char *filename,
struct stat *statbuf UNUSED_PARAM,
void *userdata UNUSED_PARAM,
int depth UNUSED_PARAM)
{
char *tokens[3];
parser_t *p;
struct module_entry *m;
int rc = TRUE;
if (bb_basename(filename)[0] == '.')
goto error;
p = config_open2(filename, fopen_for_read);
if (p == NULL) {
rc = FALSE;
goto error;
}
while (config_read(p, tokens, 3, 2, "# \t", PARSE_NORMAL)) {
//Use index_in_strings?
if (strcmp(tokens[0], "alias") == 0) {
/* alias <wildcard> <modulename> */
llist_t *l;
char wildcard[MODULE_NAME_LEN];
char *rmod;
if (tokens[2] == NULL)
continue;
filename2modname(tokens[1], wildcard);
for (l = G.probes; l != NULL; l = l->link) {
m = (struct module_entry *) l->data;
if (fnmatch(wildcard, m->modname, 0) != 0)
continue;
rmod = filename2modname(tokens[2], NULL);
llist_add_to(&m->realnames, rmod);
if (m->flags & MODULE_FLAG_NEED_DEPS) {
m->flags &= ~MODULE_FLAG_NEED_DEPS;
G.num_unresolved_deps--;
}
m = get_or_add_modentry(rmod);
if (!(m->flags & MODULE_FLAG_NEED_DEPS)) {
m->flags |= MODULE_FLAG_NEED_DEPS;
G.num_unresolved_deps++;
}
}
} else if (strcmp(tokens[0], "options") == 0) {
/* options <modulename> <option...> */
if (tokens[2] == NULL)
continue;
m = get_or_add_modentry(tokens[1]);
m->options = gather_options_str(m->options, tokens[2]);
} else if (strcmp(tokens[0], "include") == 0) {
/* include <filename> */
read_config(tokens[1]);
} else if (ENABLE_FEATURE_MODPROBE_BLACKLIST
&& strcmp(tokens[0], "blacklist") == 0
) {
/* blacklist <modulename> */
get_or_add_modentry(tokens[1])->flags |= MODULE_FLAG_BLACKLISTED;
}
}
config_close(p);
error:
return rc;
}
static int read_config(const char *path)
{
return recursive_action(path, ACTION_RECURSE | ACTION_QUIET,
config_file_action, NULL, NULL, 1);
}
static int do_modprobe(struct module_entry *m)
{
struct module_entry *m2;
char *fn, *options;
int rc = -1;
if (!(m->flags & MODULE_FLAG_FOUND_IN_MODDEP)) {
DBG("skipping %s, not found in modules.dep", m->modname);
return -ENOENT;
}
DBG("do_modprob'ing %s", m->modname);
if (!(option_mask32 & MODPROBE_OPT_REMOVE))
m->deps = llist_rev(m->deps);
rc = 0;
while (m->deps && rc == 0) {
fn = llist_pop(&m->deps);
m2 = get_or_add_modentry(fn);
if (option_mask32 & MODPROBE_OPT_REMOVE) {
if (bb_delete_module(m->modname, O_EXCL) != 0)
rc = errno;
} else if (!(m2->flags & MODULE_FLAG_LOADED)) {
options = m2->options;
m2->options = NULL;
if (m == m2)
options = gather_options_str(options, G.cmdline_mopts);
rc = bb_init_module(fn, options);
DBG("loaded %s '%s', rc:%d", fn, options, rc);
if (rc == 0)
m2->flags |= MODULE_FLAG_LOADED;
free(options);
} else {
DBG("%s is already loaded, skipping", fn);
}
free(fn);
}
//FIXME: what if rc < 0?
if (rc > 0 && !(option_mask32 & INSMOD_OPT_SILENT)) {
bb_error_msg("failed to %sload module %s: %s",
(option_mask32 & MODPROBE_OPT_REMOVE) ? "un" : "",
m->probed_name ? m->probed_name : m->modname,
moderror(rc)
);
}
return rc;
}
static void load_modules_dep(void)
{
struct module_entry *m;
char *colon, *tokens[2];
parser_t *p;
/* Modprobe does not work at all without modprobe.dep,
* even if the full module name is given. Returning error here
* was making us later confuse user with this message:
* "module /full/path/to/existing/file/module.ko not found".
* It's better to die immediately, with good message.
* xfopen_for_read provides that. */
p = config_open2(CONFIG_DEFAULT_DEPMOD_FILE, xfopen_for_read);
while (G.num_unresolved_deps
&& config_read(p, tokens, 2, 1, "# \t", PARSE_NORMAL)
) {
colon = last_char_is(tokens[0], ':');
if (colon == NULL)
continue;
*colon = 0;
m = get_modentry(tokens[0]);
if (m == NULL)
continue;
/* Optimization... */
if ((m->flags & MODULE_FLAG_LOADED)
&& !(option_mask32 & MODPROBE_OPT_REMOVE)
) {
DBG("skip deps of %s, it's already loaded", tokens[0]);
continue;
}
m->flags |= MODULE_FLAG_FOUND_IN_MODDEP;
if ((m->flags & MODULE_FLAG_NEED_DEPS) && (m->deps == NULL)) {
G.num_unresolved_deps--;
llist_add_to(&m->deps, xstrdup(tokens[0]));
if (tokens[1])
string_to_llist(tokens[1], &m->deps, " ");
}
}
config_close(p);
}
int modprobe_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int modprobe_main(int argc UNUSED_PARAM, char **argv)
{
struct utsname uts;
int rc;
unsigned opt;
struct module_entry *me;
opt_complementary = "q-v:v-q";
opt = getopt32(argv, INSMOD_OPTS MODPROBE_OPTS INSMOD_ARGS, NULL, NULL);
argv += optind;
if (opt & (MODPROBE_OPT_DUMP_ONLY | MODPROBE_OPT_LIST_ONLY |
MODPROBE_OPT_SHOW_ONLY))
bb_error_msg_and_die("not supported");
if (!argv[0]) {
if (opt & MODPROBE_OPT_REMOVE) {
/* "modprobe -r" (w/o params).
* "If name is NULL, all unused modules marked
* autoclean will be removed".
*/
if (bb_delete_module(NULL, O_NONBLOCK|O_EXCL) != 0)
bb_perror_msg_and_die("rmmod");
}
return EXIT_SUCCESS;
}
/* Goto modules location */
xchdir(CONFIG_DEFAULT_MODULES_DIR);
uname(&uts);
xchdir(uts.release);
/* Retrieve module names of already loaded modules */
{
char *s;
parser_t *parser = config_open2("/proc/modules", fopen_for_read);
while (config_read(parser, &s, 1, 1, "# \t", PARSE_NORMAL & ~PARSE_GREEDY))
get_or_add_modentry(s)->flags |= MODULE_FLAG_LOADED;
config_close(parser);
}
if (opt & MODPROBE_OPT_INSERT_ALL) {
/* Each argument is a module name */
do {
add_probe(*argv++);
} while (*argv);
} else {
/* First argument is module name, rest are parameters */
add_probe(argv[0]);
G.cmdline_mopts = parse_cmdline_module_options(argv);
}
/* Happens if all requested modules are already loaded */
if (G.probes == NULL)
return EXIT_SUCCESS;
read_config("/etc/modprobe.conf");
read_config("/etc/modprobe.d");
if (ENABLE_FEATURE_MODUTILS_SYMBOLS && G.need_symbols)
read_config("modules.symbols");
load_modules_dep();
if (ENABLE_FEATURE_MODUTILS_ALIAS && G.num_unresolved_deps) {
read_config("modules.alias");
load_modules_dep();
}
while ((me = llist_pop(&G.probes)) != NULL) {
if (me->realnames == NULL) {
/* This is not an alias. Literal names are blacklisted
* only if '-b' is given.
*/
if (!(opt & MODPROBE_OPT_BLACKLIST)
|| !(me->flags & MODULE_FLAG_BLACKLISTED)
) {
rc = do_modprobe(me);
//FIXME: what if rc > 0?
if (rc < 0 && !(opt & INSMOD_OPT_SILENT))
bb_error_msg("module %s not found",
me->probed_name);
}
} else {
/* Probe all realnames */
do {
char *realname = llist_pop(&me->realnames);
struct module_entry *m2;
DBG("probing %s by realname %s", me->modname, realname);
m2 = get_or_add_modentry(realname);
if (!(m2->flags & MODULE_FLAG_BLACKLISTED))
do_modprobe(m2);
//FIXME: error check?
free(realname);
} while (me->realnames != NULL);
}
}
return EXIT_SUCCESS;
}
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