kmod-modprobe: implement softdeps.

Implement soft dependencies in a way similar to module-init-tools
modprobe. Unlike regular dependencies they are allowed to fail
inserting or removing.

The rmmod version walks the lists in reverse order, also doing post
before and pre later.

diff --git a/TODO b/TODO
index 47a6aa8d55bac43a7867226df09f59a90b745201..d174a877bca8f5b3dc82b3eaae3845fa8f9a7309 100644 (file)
--- a/TODO
+++ b/TODO
@@ -20,7 +20,6 @@ Features:
 * provide 1:1 compatibility with module-init-tools's modprobe
    - show modversions (needs elf manipulation)
    - dump configuration
-   - use softdep
    - install and remove commands may exist when there's no module with that
      name. Properly handle this case
 

diff --git a/tools/kmod-modprobe.c b/tools/kmod-modprobe.c
index 5b9ed7cb53839e1a2fb4d432d3e3d7f3a7b34581..2ea8d08317ac07bc53ef58194b5f9fbbc83528eb 100644 (file)
--- a/tools/kmod-modprobe.c
+++ b/tools/kmod-modprobe.c
@@ -297,19 +297,17 @@ end:
        return ret;
 }
 
-static int rmmod_do_soft_dependencies(struct kmod_module *mod)
-{
-       ERR("TODO - implement soft dependencies!\n");
-       /* remember to reverse soft dependencies! */
-       return 0;
-}
+static int rmmod_do_dependencies(struct kmod_module *parent);
+static int rmmod_do_soft_dependencies(struct kmod_module *mod, struct kmod_list *deps);
 
-static int rmmod_do_dependencies(struct kmod_module *parent)
+static int rmmod_do_deps_list(struct kmod_module *parent, struct kmod_list *deps, unsigned stop_on_errors)
 {
+       struct kmod_list *d;
        int err = 0;
-       struct kmod_list *d, *deps = kmod_module_get_holders(parent);
-       kmod_list_foreach(d, deps) {
+
+       kmod_list_foreach_reverse(d, deps) {
                struct kmod_module *dm = kmod_module_get_module(d);
+               struct kmod_list *pre = NULL, *post = NULL;
                const char *cmd, *dmname = kmod_module_get_name(dm);
                int r;
 
@@ -320,20 +318,27 @@ static int rmmod_do_dependencies(struct kmod_module *parent)
                        goto dep_error;
                }
 
-               if (!ignore_loaded) {
-                       int state = kmod_module_get_initstate(dm);
-                       if (state != KMOD_MODULE_LIVE &&
-                                       state != KMOD_MODULE_COMING)
-                               goto dep_done;
+               r = kmod_module_get_softdeps(dm, &pre, &post);
+               if (r < 0) {
+                       WRN("could not get softdeps of '%s': %s\n",
+                           dmname, strerror(-r));
+                       goto dep_done;
                }
 
-               r = rmmod_do_soft_dependencies(dm);
+               r = rmmod_do_soft_dependencies(dm, post);
                if (r < 0) {
-                       WRN("could not remove soft dependencies of '%s': %s\n",
+                       WRN("could not remove post soft softdeps of '%s': %s\n",
                            dmname, strerror(-r));
                        goto dep_error;
                }
 
+               if (!ignore_loaded) {
+                       int state = kmod_module_get_initstate(dm);
+                       if (state != KMOD_MODULE_LIVE &&
+                                       state != KMOD_MODULE_COMING)
+                               goto dep_done;
+               }
+
                cmd = kmod_module_get_remove_commands(dm);
                if (cmd) {
                        r = command_do(dm, "remove", cmd, NULL);
@@ -368,13 +373,40 @@ static int rmmod_do_dependencies(struct kmod_module *parent)
                }
 
        dep_done:
+               r = rmmod_do_soft_dependencies(dm, pre);
+               if (r < 0) {
+                       WRN("could not remove pre softdeps of '%s': %s\n",
+                           dmname, strerror(-r));
+                       goto dep_error;
+               }
+               kmod_module_unref_list(pre);
+               kmod_module_unref_list(post);
                kmod_module_unref(dm);
                continue;
+
        dep_error:
                err = r;
+               kmod_module_unref_list(pre);
+               kmod_module_unref_list(post);
                kmod_module_unref(dm);
-               continue;
+               if (stop_on_errors)
+                       break;
+               else
+                       continue;
        }
+
+       return err;
+}
+
+static int rmmod_do_soft_dependencies(struct kmod_module *mod, struct kmod_list *deps)
+{
+       return rmmod_do_deps_list(mod, deps, 0);
+}
+
+static int rmmod_do_dependencies(struct kmod_module *parent)
+{
+       struct kmod_list *deps = kmod_module_get_holders(parent);
+       int err = rmmod_do_deps_list(parent, deps, 1);
        kmod_module_unref_list(deps);
        return err;
 }
@@ -382,6 +414,7 @@ static int rmmod_do_dependencies(struct kmod_module *parent)
 static int rmmod_do(struct kmod_module *mod)
 {
        const char *modname = kmod_module_get_name(mod);
+       struct kmod_list *pre = NULL, *post = NULL;
        int err;
 
        if (!ignore_loaded) {
@@ -408,20 +441,33 @@ static int rmmod_do(struct kmod_module *mod)
        if (!ignore_commands) {
                const char *cmd;
 
-               err = rmmod_do_soft_dependencies(mod);
-               if (err < 0)
+               err = kmod_module_get_softdeps(mod, &pre, &post);
+               if (err < 0) {
+                       WRN("could not get softdeps of '%s': %s\n",
+                           modname, strerror(-err));
                        return err;
+               }
+
+               err = rmmod_do_soft_dependencies(mod, post);
+               if (err < 0) {
+                       WRN("could not remove post softdeps of '%s': %s\n",
+                           modname, strerror(-err));
+                       goto error;
+               }
 
                cmd = kmod_module_get_remove_commands(mod);
-               if (cmd)
-                       return command_do(mod, "remove", cmd, NULL);
+               if (cmd != NULL) {
+                       err = command_do(mod, "remove", cmd, NULL);
+                       goto done;
+               }
        }
 
        if (!ignore_loaded) {
                int usage = kmod_module_get_refcnt(mod);
                if (usage > 0) {
                        LOG("Module %s is in use.\n", modname);
-                       return -EBUSY;
+                       err = -EBUSY;
+                       goto error;
                }
        }
 
@@ -443,6 +489,20 @@ static int rmmod_do(struct kmod_module *mod)
                                LOG("Module %s is not in kernel.\n", modname);
                }
        }
+
+done:
+       if (!ignore_commands) {
+               err = rmmod_do_soft_dependencies(mod, pre);
+               if (err < 0) {
+                       WRN("could not remove pre softdeps of '%s': %s\n",
+                           modname, strerror(-err));
+                       goto error;
+               }
+       }
+
+error:
+       kmod_module_unref_list(pre);
+       kmod_module_unref_list(post);
        return err;
 }
 
@@ -516,18 +576,17 @@ static int rmmod_all(struct kmod_ctx *ctx, char **args, int nargs)
        return err;
 }
 
-static int insmod_do_soft_dependencies(struct kmod_module *mod)
-{
-       ERR("TODO - implement soft dependencies!\n");
-       return 0;
-}
+static int insmod_do_dependencies(struct kmod_module *parent);
+static int insmod_do_soft_dependencies(struct kmod_module *mod, struct kmod_list *deps);
 
-static int insmod_do_dependencies(struct kmod_module *parent)
+static int insmod_do_deps_list(struct kmod_module *parent, struct kmod_list *deps, unsigned stop_on_errors)
 {
+       struct kmod_list *d;
        int err = 0;
-       struct kmod_list *d, *deps = kmod_module_get_dependencies(parent);
+
        kmod_list_foreach(d, deps) {
                struct kmod_module *dm = kmod_module_get_module(d);
+               struct kmod_list *pre = NULL, *post = NULL;
                const char *cmd, *opts, *dmname = kmod_module_get_name(dm);
                int r;
 
@@ -538,6 +597,20 @@ static int insmod_do_dependencies(struct kmod_module *parent)
                        goto dep_error;
                }
 
+               r = kmod_module_get_softdeps(dm, &pre, &post);
+               if (r < 0) {
+                       WRN("could not get softdeps of '%s': %s\n",
+                           dmname, strerror(-r));
+                       goto dep_done;
+               }
+
+               r = insmod_do_soft_dependencies(dm, pre);
+               if (r < 0) {
+                       WRN("could not insert pre softdeps of '%s': %s\n",
+                           dmname, strerror(-r));
+                       goto dep_error;
+               }
+
                if (!ignore_loaded) {
                        int state = kmod_module_get_initstate(dm);
                        if (state == KMOD_MODULE_LIVE ||
@@ -546,13 +619,6 @@ static int insmod_do_dependencies(struct kmod_module *parent)
                                goto dep_done;
                }
 
-               r = insmod_do_soft_dependencies(dm);
-               if (r < 0) {
-                       WRN("could not insert soft dependencies of '%s': %s\n",
-                           dmname, strerror(-r));
-                       goto dep_error;
-               }
-
                cmd = kmod_module_get_install_commands(dm);
                if (cmd) {
                        r = command_do(dm, "install", cmd, NULL);
@@ -585,13 +651,41 @@ static int insmod_do_dependencies(struct kmod_module *parent)
                }
 
        dep_done:
+               r = insmod_do_soft_dependencies(dm, post);
+               if (r < 0) {
+                       WRN("could not insert post softdeps of '%s': %s\n",
+                           dmname, strerror(-r));
+                       goto dep_error;
+               }
+
+               kmod_module_unref_list(pre);
+               kmod_module_unref_list(post);
                kmod_module_unref(dm);
                continue;
+
        dep_error:
                err = r;
+               kmod_module_unref_list(pre);
+               kmod_module_unref_list(post);
                kmod_module_unref(dm);
-               continue;
+               if (stop_on_errors)
+                       break;
+               else
+                       continue;
        }
+
+       return err;
+}
+
+static int insmod_do_soft_dependencies(struct kmod_module *mod, struct kmod_list *deps)
+{
+       return insmod_do_deps_list(mod, deps, 0);
+}
+
+static int insmod_do_dependencies(struct kmod_module *parent)
+{
+       struct kmod_list *deps = kmod_module_get_dependencies(parent);
+       int err = insmod_do_deps_list(parent, deps, 1);
        kmod_module_unref_list(deps);
        return err;
 }
@@ -600,6 +694,7 @@ static int insmod_do(struct kmod_module *mod, const char *extra_opts)
 {
        const char *modname = kmod_module_get_name(mod);
        const char *conf_opts = kmod_module_get_options(mod);
+       struct kmod_list *pre = NULL, *post = NULL;
        char *opts = NULL;
        int err;
 
@@ -629,13 +724,25 @@ static int insmod_do(struct kmod_module *mod, const char *extra_opts)
        if (!ignore_commands) {
                const char *cmd;
 
-               err = insmod_do_soft_dependencies(mod);
-               if (err < 0)
+               err = kmod_module_get_softdeps(mod, &pre, &post);
+               if (err < 0) {
+                       WRN("could not get softdeps of '%s': %s\n",
+                           modname, strerror(-err));
                        return err;
+               }
+
+               err = insmod_do_soft_dependencies(mod, pre);
+               if (err < 0) {
+                       WRN("could not insert pre softdeps of '%s': %s\n",
+                           modname, strerror(-err));
+                       goto error;
+               }
 
                cmd = kmod_module_get_install_commands(mod);
-               if (cmd)
-                       return command_do(mod, "install", cmd, extra_opts);
+               if (cmd != NULL) {
+                       err = command_do(mod, "install", cmd, extra_opts);
+                       goto done;
+               }
        }
 
        if (conf_opts || extra_opts) {
@@ -646,8 +753,10 @@ static int insmod_do(struct kmod_module *mod, const char *extra_opts)
                else if (asprintf(&opts, "%s %s", conf_opts, extra_opts) < 0)
                        opts = NULL;
 
-               if (opts == NULL)
-                       return -ENOMEM;
+               if (opts == NULL) {
+                       err = -ENOMEM;
+                       goto error;
+               }
        }
 
        SHOW("insmod %s %s\n", kmod_module_get_path(mod), opts ? opts : "");
@@ -671,6 +780,20 @@ static int insmod_do(struct kmod_module *mod, const char *extra_opts)
                                        kmod_module_get_name(mod));
                }
        }
+
+done:
+       if (!ignore_commands) {
+               err = insmod_do_soft_dependencies(mod, post);
+               if (err < 0) {
+                       WRN("could not insert post softdeps of '%s': %s\n",
+                           modname, strerror(-err));
+                       goto error;
+               }
+       }
+
+error:
+       kmod_module_unref_list(pre);
+       kmod_module_unref_list(post);
        free(opts);
        return err;
 }