kmodloader: support loading module options and blacklist from /etc/modules.conf
authorFelix Fietkau <nbd@nbd.name>
Thu, 6 Jan 2022 14:58:11 +0000 (15:58 +0100)
committerFelix Fietkau <nbd@nbd.name>
Thu, 6 Jan 2022 14:58:14 +0000 (15:58 +0100)
This has the same format as /etc/modules.d on a regular linux system

Signed-off-by: Felix Fietkau <nbd@nbd.name>
kmodloader.c

index 6f06ee3939f2f3e151357d33cfd165603cb40e4d..26926a021be474bac5fd7e9db07aa8b79e43602a 100644 (file)
 #include <libgen.h>
 #include <glob.h>
 #include <elf.h>
+#include <ctype.h>
 
 #include <libubox/avl.h>
 #include <libubox/avl-cmp.h>
 #include <libubox/utils.h>
 #include <libubox/ulog.h>
+#include <libubox/kvlist.h>
 
 #define DEF_MOD_PATH "/modules/%s/"
 /* duplicated from in-kernel include/linux/module.h */
@@ -44,6 +46,7 @@ enum {
        SCANNED,
        PROBE,
        LOADED,
+       BLACKLISTED,
 };
 
 struct module {
@@ -65,6 +68,7 @@ struct module_node {
 };
 
 static struct avl_tree modules;
+static KVLIST(options, kvlist_strlen);
 
 static char **module_folders = NULL;
 
@@ -435,15 +439,29 @@ static int scan_module_folder(const char *dir)
        for (j = 0; j < gl.gl_pathc; j++) {
                char *name = get_module_name(gl.gl_pathv[j]);
                struct module *m;
+               char *opts;
 
                if (!name)
                        continue;
 
                m = find_module(name);
+               if (m)
+                       continue;
+
+               m = get_module_info(gl.gl_pathv[j], name);
                if (!m) {
-                       if (!get_module_info(gl.gl_pathv[j], name))
-                               rv |= -1;
+                       rv |= -1;
+                       continue;
                }
+
+               opts = kvlist_get(&options, name);
+               if (!opts)
+                       continue;
+
+               if (*opts == '\x01')
+                       m->state = BLACKLISTED;
+               else
+                       m->opts = strdup(opts);
        }
 
        globfree(&gl);
@@ -901,7 +919,10 @@ static int main_modprobe(int argc, char **argv)
                name = get_module_name(argv[optind]);
                m = find_module(name);
 
-               if (m && m->state == LOADED) {
+               if (m && m->state == BLACKLISTED) {
+                       if (!quiet)
+                               ULOG_INFO("%s is blacklisted\n", name);
+               } else if (m && m->state == LOADED) {
                        if (!quiet)
                                ULOG_INFO("%s is already loaded\n", name);
                } else if (!m) {
@@ -996,11 +1017,19 @@ static int main_loader(int argc, char **argv)
                                *opts++ = '\0';
 
                        m = find_module(get_module_name(mod));
-                       if (!m || (m->state == LOADED))
+                       if (!m || m->state == LOADED || m->state == BLACKLISTED)
                                continue;
 
-                       if (opts)
-                               m->opts = strdup(opts);
+                       if (opts) {
+                               if (m->opts) {
+                                       char *prev = m->opts;
+
+                                       asprintf(&m->opts, "%s %s", prev, opts);
+                                       free(prev);
+                               } else {
+                                       m->opts = strdup(opts);
+                               }
+                       }
                        m->state = PROBE;
                        if (basename(gl.gl_pathv[j])[0] - '0' <= 9)
                                load_modprobe(false);
@@ -1053,6 +1082,80 @@ static int avl_modcmp(const void *k1, const void *k2, void *ptr)
        return (unsigned char)weight(*s1) - (unsigned char)weight(*s2);
 }
 
+static void
+load_options(void)
+{
+       static char buf[512];
+       char *s;
+       FILE *f;
+
+       f = fopen("/etc/modules.conf", "r");
+       if (!f)
+               return;
+
+       while ((s = fgets(buf, sizeof(buf), f)) != NULL) {
+               char *c, *cmd, *mod;
+
+               while (isspace(*s))
+                       s++;
+
+               c = strchr(s, '#');
+               if (c)
+                       *c = 0;
+
+               while (isspace(*s))
+                       s++;
+
+               c = s + strlen(s);
+               while (c > s && isspace(c[-1])) {
+                       c[-1] = 0;
+                       c--;
+               }
+
+               cmd = strsep(&s, " \t");
+               if (!cmd || !*cmd)
+                       continue;
+
+               while (isspace(*s))
+                       s++;
+
+               mod = strsep(&s, " \t");
+               if (!mod || !*mod)
+                       continue;
+
+               if (!strcmp(cmd, "blacklist")) {
+                       kvlist_set(&options, mod, "\x01");
+                       continue;
+               }
+
+               if (!strcmp(cmd, "options")) {
+                       char *prev = kvlist_get(&options, mod);
+                       char *val = NULL;
+
+                       while (isspace(*s))
+                               s++;
+
+                       if (!*s)
+                               continue;
+
+                       if (prev && prev[0] == '\x01')
+                               continue;
+
+                       if (!prev) {
+                               kvlist_set(&options, mod, s);
+                               continue;
+                       }
+
+                       if (asprintf(&val, "%s %s", prev, s) < 0)
+                               continue;
+
+                       kvlist_set(&options, mod, val);
+                       free(val);
+                       continue;
+               }
+       }
+}
+
 int main(int argc, char **argv)
 {
        char *exec = basename(*argv);
@@ -1070,6 +1173,8 @@ int main(int argc, char **argv)
        if (!strcmp(exec, "modinfo"))
                return main_modinfo(argc, argv);
 
+       load_options();
+
        if (!strcmp(exec, "modprobe"))
                return main_modprobe(argc, argv);