/* $NetBSD: kern_module.c,v 1.98 2014/08/24 07:59:23 jnemeth Exp $ */ /*- * Copyright (c) 2008 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software developed for The NetBSD Foundation * by Andrew Doran. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /* * Kernel module support. */ #include __KERNEL_RCSID(0, "$NetBSD: kern_module.c,v 1.98 2014/08/24 07:59:23 jnemeth Exp $"); #define _MODULE_INTERNAL #ifdef _KERNEL_OPT #include "opt_ddb.h" #include "opt_modular.h" #endif #include #include #include #include #include #include #include #include #include #include #include #include struct vm_map *module_map; char *module_machine; char module_base[MODULE_BASE_SIZE]; struct modlist module_list = TAILQ_HEAD_INITIALIZER(module_list); struct modlist module_builtins = TAILQ_HEAD_INITIALIZER(module_builtins); static struct modlist module_bootlist = TAILQ_HEAD_INITIALIZER(module_bootlist); static module_t *module_active; static bool module_verbose_on; #ifdef MODULE_DEFAULT_AUTOLOAD static bool module_autoload_on = true; #else static bool module_autoload_on = false; #endif u_int module_count; u_int module_builtinlist; u_int module_autotime = 10; u_int module_gen = 1; static kcondvar_t module_thread_cv; static kmutex_t module_thread_lock; static int module_thread_ticks; int (*module_load_vfs_vec)(const char *, int, bool, module_t *, prop_dictionary_t *) = (void *)eopnotsupp; static kauth_listener_t module_listener; /* Ensure that the kernel's link set isn't empty. */ static modinfo_t module_dummy; __link_set_add_rodata(modules, module_dummy); static module_t *module_newmodule(modsrc_t); static void module_require_force(module_t *); static int module_do_load(const char *, bool, int, prop_dictionary_t, module_t **, modclass_t class, bool); static int module_do_unload(const char *, bool); static int module_do_builtin(const char *, module_t **, prop_dictionary_t); static int module_fetch_info(module_t *); static void module_thread(void *); static module_t *module_lookup(const char *); static void module_enqueue(module_t *); static bool module_merge_dicts(prop_dictionary_t, const prop_dictionary_t); static void sysctl_module_setup(void); static int sysctl_module_autotime(SYSCTLFN_PROTO); #define MODULE_CLASS_MATCH(mi, class) \ ((class) == MODULE_CLASS_ANY || (class) == (mi)->mi_class) static void module_incompat(const modinfo_t *mi, int class) { module_error("incompatible module class for `%s' (%d != %d)", mi->mi_name, class, mi->mi_class); } /* * module_error: * * Utility function: log an error. */ void module_error(const char *fmt, ...) { va_list ap; va_start(ap, fmt); printf("WARNING: module error: "); vprintf(fmt, ap); printf("\n"); va_end(ap); } /* * module_print: * * Utility function: log verbose output. */ void module_print(const char *fmt, ...) { va_list ap; if (module_verbose_on) { va_start(ap, fmt); printf("DEBUG: module: "); vprintf(fmt, ap); printf("\n"); va_end(ap); } } static int module_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie, void *arg0, void *arg1, void *arg2, void *arg3) { int result; result = KAUTH_RESULT_DEFER; if (action != KAUTH_SYSTEM_MODULE) return result; if ((uintptr_t)arg2 != 0) /* autoload */ result = KAUTH_RESULT_ALLOW; return result; } /* * Allocate a new module_t */ static module_t * module_newmodule(modsrc_t source) { module_t *mod; mod = kmem_zalloc(sizeof(*mod), KM_SLEEP); if (mod != NULL) { mod->mod_source = source; mod->mod_info = NULL; mod->mod_flags = 0; } return mod; } /* * Require the -f (force) flag to load a module */ static void module_require_force(struct module *mod) { mod->mod_flags |= MODFLG_MUST_FORCE; } /* * Add modules to the builtin list. This can done at boottime or * at runtime if the module is linked into the kernel with an * external linker. All or none of the input will be handled. * Optionally, the modules can be initialized. If they are not * initialized, module_init_class() or module_load() can be used * later, but these are not guaranteed to give atomic results. */ int module_builtin_add(modinfo_t *const *mip, size_t nmodinfo, bool init) { struct module **modp = NULL, *mod_iter; int rv = 0, i, mipskip; if (init) { rv = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 0, (void *)(uintptr_t)MODCTL_LOAD, (void *)(uintptr_t)1, NULL); if (rv) { return rv; } } for (i = 0, mipskip = 0; i < nmodinfo; i++) { if (mip[i] == &module_dummy) { KASSERT(nmodinfo > 0); nmodinfo--; } } if (nmodinfo == 0) return 0; modp = kmem_zalloc(sizeof(*modp) * nmodinfo, KM_SLEEP); for (i = 0, mipskip = 0; i < nmodinfo; i++) { if (mip[i+mipskip] == &module_dummy) { mipskip++; continue; } modp[i] = module_newmodule(MODULE_SOURCE_KERNEL); modp[i]->mod_info = mip[i+mipskip]; } kernconfig_lock(); /* do this in three stages for error recovery and atomicity */ /* first check for presence */ for (i = 0; i < nmodinfo; i++) { TAILQ_FOREACH(mod_iter, &module_builtins, mod_chain) { if (strcmp(mod_iter->mod_info->mi_name, modp[i]->mod_info->mi_name) == 0) break; } if (mod_iter) { rv = EEXIST; goto out; } if (module_lookup(modp[i]->mod_info->mi_name) != NULL) { rv = EEXIST; goto out; } } /* then add to list */ for (i = 0; i < nmodinfo; i++) { TAILQ_INSERT_TAIL(&module_builtins, modp[i], mod_chain); module_builtinlist++; } /* finally, init (if required) */ if (init) { for (i = 0; i < nmodinfo; i++) { rv = module_do_builtin(modp[i]->mod_info->mi_name, NULL, NULL); /* throw in the towel, recovery hard & not worth it */ if (rv) panic("builtin module \"%s\" init failed: %d", modp[i]->mod_info->mi_name, rv); } } out: kernconfig_unlock(); if (rv != 0) { for (i = 0; i < nmodinfo; i++) { if (modp[i]) kmem_free(modp[i], sizeof(*modp[i])); } } kmem_free(modp, sizeof(*modp) * nmodinfo); return rv; } /* * Optionally fini and remove builtin module from the kernel. * Note: the module will now be unreachable except via mi && builtin_add. */ int module_builtin_remove(modinfo_t *mi, bool fini) { struct module *mod; int rv = 0; if (fini) { rv = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 0, (void *)(uintptr_t)MODCTL_UNLOAD, NULL, NULL); if (rv) return rv; kernconfig_lock(); rv = module_do_unload(mi->mi_name, true); if (rv) { goto out; } } else { kernconfig_lock(); } TAILQ_FOREACH(mod, &module_builtins, mod_chain) { if (strcmp(mod->mod_info->mi_name, mi->mi_name) == 0) break; } if (mod) { TAILQ_REMOVE(&module_builtins, mod, mod_chain); module_builtinlist--; } else { KASSERT(fini == false); rv = ENOENT; } out: kernconfig_unlock(); return rv; } /* * module_init: * * Initialize the module subsystem. */ void module_init(void) { __link_set_decl(modules, modinfo_t); extern struct vm_map *module_map; modinfo_t *const *mip; int rv; if (module_map == NULL) { module_map = kernel_map; } cv_init(&module_thread_cv, "mod_unld"); mutex_init(&module_thread_lock, MUTEX_DEFAULT, IPL_NONE); #ifdef MODULAR /* XXX */ module_init_md(); #endif if (!module_machine) module_machine = machine; #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ snprintf(module_base, sizeof(module_base), "/stand/%s/%s/modules", module_machine, osrelease); #else /* release */ snprintf(module_base, sizeof(module_base), "/stand/%s/%d.%d/modules", module_machine, __NetBSD_Version__ / 100000000, __NetBSD_Version__ / 1000000 % 100); #endif module_listener = kauth_listen_scope(KAUTH_SCOPE_SYSTEM, module_listener_cb, NULL); __link_set_foreach(mip, modules) { if ((rv = module_builtin_add(mip, 1, false)) != 0) module_error("builtin %s failed: %d\n", (*mip)->mi_name, rv); } sysctl_module_setup(); aprint_normal("kern.module.path=%s\n", module_base); } /* * module_start_unload_thread: * * Start the auto unload kthread. */ void module_start_unload_thread(void) { int error; error = kthread_create(PRI_VM, KTHREAD_MPSAFE, NULL, module_thread, NULL, NULL, "modunload"); if (error != 0) panic("module_init: %d", error); } /* * module_builtin_require_force * * Require MODCTL_MUST_FORCE to load any built-in modules that have * not yet been initialized */ void module_builtin_require_force(void) { module_t *mod; kernconfig_lock(); TAILQ_FOREACH(mod, &module_builtins, mod_chain) { module_require_force(mod); } kernconfig_unlock(); } static struct sysctllog *module_sysctllog; static int sysctl_module_autotime(SYSCTLFN_ARGS) { struct sysctlnode node; int t, error; t = *(int *)rnode->sysctl_data; node = *rnode; node.sysctl_data = &t; error = sysctl_lookup(SYSCTLFN_CALL(&node)); if (error || newp == NULL) return (error); if (t < 0) return (EINVAL); *(int *)rnode->sysctl_data = t; return (0); } static void sysctl_module_setup(void) { const struct sysctlnode *node = NULL; sysctl_createv(&module_sysctllog, 0, NULL, &node, CTLFLAG_PERMANENT, CTLTYPE_NODE, "module", SYSCTL_DESCR("Module options"), NULL, 0, NULL, 0, CTL_KERN, CTL_CREATE, CTL_EOL); if (node == NULL) return; sysctl_createv(&module_sysctllog, 0, &node, NULL, CTLFLAG_PERMANENT | CTLFLAG_READWRITE, CTLTYPE_BOOL, "autoload", SYSCTL_DESCR("Enable automatic load of modules"), NULL, 0, &module_autoload_on, 0, CTL_CREATE, CTL_EOL); sysctl_createv(&module_sysctllog, 0, &node, NULL, CTLFLAG_PERMANENT | CTLFLAG_READWRITE, CTLTYPE_BOOL, "verbose", SYSCTL_DESCR("Enable verbose output"), NULL, 0, &module_verbose_on, 0, CTL_CREATE, CTL_EOL); sysctl_createv(&module_sysctllog, 0, &node, NULL, CTLFLAG_PERMANENT | CTLFLAG_READONLY, CTLTYPE_STRING, "path", SYSCTL_DESCR("Default module load path"), NULL, 0, module_base, 0, CTL_CREATE, CTL_EOL); sysctl_createv(&module_sysctllog, 0, &node, NULL, CTLFLAG_PERMANENT | CTLFLAG_READWRITE, CTLTYPE_INT, "autotime", SYSCTL_DESCR("Auto-unload delay"), sysctl_module_autotime, 0, &module_autotime, 0, CTL_CREATE, CTL_EOL); } /* * module_init_class: * * Initialize all built-in and pre-loaded modules of the * specified class. */ void module_init_class(modclass_t class) { TAILQ_HEAD(, module) bi_fail = TAILQ_HEAD_INITIALIZER(bi_fail); module_t *mod; modinfo_t *mi; kernconfig_lock(); /* * Builtins first. These will not depend on pre-loaded modules * (because the kernel would not link). */ do { TAILQ_FOREACH(mod, &module_builtins, mod_chain) { mi = mod->mod_info; if (!MODULE_CLASS_MATCH(mi, class)) continue; /* * If initializing a builtin module fails, don't try * to load it again. But keep it around and queue it * on the builtins list after we're done with module * init. Don't set it to MODFLG_MUST_FORCE in case a * future attempt to initialize can be successful. * (If the module has previously been set to * MODFLG_MUST_FORCE, don't try to override that!) */ if (mod->mod_flags & MODFLG_MUST_FORCE || module_do_builtin(mi->mi_name, NULL, NULL) != 0) { TAILQ_REMOVE(&module_builtins, mod, mod_chain); TAILQ_INSERT_TAIL(&bi_fail, mod, mod_chain); } break; } } while (mod != NULL); /* * Now preloaded modules. These will be pulled off the * list as we call module_do_load(); */ do { TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { mi = mod->mod_info; if (!MODULE_CLASS_MATCH(mi, class)) continue; module_do_load(mi->mi_name, false, 0, NULL, NULL, class, false); break; } } while (mod != NULL); /* return failed builtin modules to builtin list */ while ((mod = TAILQ_FIRST(&bi_fail)) != NULL) { TAILQ_REMOVE(&bi_fail, mod, mod_chain); TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain); } kernconfig_unlock(); } /* * module_compatible: * * Return true if the two supplied kernel versions are said to * have the same binary interface for kernel code. The entire * version is signficant for the development tree (-current), * major and minor versions are significant for official * releases of the system. */ bool module_compatible(int v1, int v2) { #if __NetBSD_Version__ / 1000000 % 100 == 99 /* -current */ return v1 == v2; #else /* release */ return abs(v1 - v2) < 10000; #endif } /* * module_load: * * Load a single module from the file system. */ int module_load(const char *filename, int flags, prop_dictionary_t props, modclass_t class) { int error; /* Authorize. */ error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 0, (void *)(uintptr_t)MODCTL_LOAD, NULL, NULL); if (error != 0) { return error; } kernconfig_lock(); error = module_do_load(filename, false, flags, props, NULL, class, false); kernconfig_unlock(); return error; } /* * module_autoload: * * Load a single module from the file system, system initiated. */ int module_autoload(const char *filename, modclass_t class) { int error; kernconfig_lock(); /* Nothing if the user has disabled it. */ if (!module_autoload_on) { kernconfig_unlock(); return EPERM; } /* Disallow path separators and magic symlinks. */ if (strchr(filename, '/') != NULL || strchr(filename, '@') != NULL || strchr(filename, '.') != NULL) { kernconfig_unlock(); return EPERM; } /* Authorize. */ error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 0, (void *)(uintptr_t)MODCTL_LOAD, (void *)(uintptr_t)1, NULL); if (error == 0) error = module_do_load(filename, false, 0, NULL, NULL, class, true); kernconfig_unlock(); return error; } /* * module_unload: * * Find and unload a module by name. */ int module_unload(const char *name) { int error; /* Authorize. */ error = kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_MODULE, 0, (void *)(uintptr_t)MODCTL_UNLOAD, NULL, NULL); if (error != 0) { return error; } kernconfig_lock(); error = module_do_unload(name, true); kernconfig_unlock(); return error; } /* * module_lookup: * * Look up a module by name. */ module_t * module_lookup(const char *name) { module_t *mod; KASSERT(kernconfig_is_held()); TAILQ_FOREACH(mod, &module_list, mod_chain) { if (strcmp(mod->mod_info->mi_name, name) == 0) { break; } } return mod; } /* * module_hold: * * Add a single reference to a module. It's the caller's * responsibility to ensure that the reference is dropped * later. */ int module_hold(const char *name) { module_t *mod; kernconfig_lock(); mod = module_lookup(name); if (mod == NULL) { kernconfig_unlock(); return ENOENT; } mod->mod_refcnt++; kernconfig_unlock(); return 0; } /* * module_rele: * * Release a reference acquired with module_hold(). */ void module_rele(const char *name) { module_t *mod; kernconfig_lock(); mod = module_lookup(name); if (mod == NULL) { kernconfig_unlock(); panic("module_rele: gone"); } mod->mod_refcnt--; kernconfig_unlock(); } /* * module_enqueue: * * Put a module onto the global list and update counters. */ void module_enqueue(module_t *mod) { int i; KASSERT(kernconfig_is_held()); /* * If there are requisite modules, put at the head of the queue. * This is so that autounload can unload requisite modules with * only one pass through the queue. */ if (mod->mod_nrequired) { TAILQ_INSERT_HEAD(&module_list, mod, mod_chain); /* Add references to the requisite modules. */ for (i = 0; i < mod->mod_nrequired; i++) { KASSERT(mod->mod_required[i] != NULL); mod->mod_required[i]->mod_refcnt++; } } else { TAILQ_INSERT_TAIL(&module_list, mod, mod_chain); } module_count++; module_gen++; } /* * module_do_builtin: * * Initialize a module from the list of modules that are * already linked into the kernel. */ static int module_do_builtin(const char *name, module_t **modp, prop_dictionary_t props) { const char *p, *s; char buf[MAXMODNAME]; modinfo_t *mi = NULL; module_t *mod, *mod2, *mod_loaded, *prev_active; size_t len; int error; KASSERT(kernconfig_is_held()); /* * Search the list to see if we have a module by this name. */ TAILQ_FOREACH(mod, &module_builtins, mod_chain) { if (strcmp(mod->mod_info->mi_name, name) == 0) { mi = mod->mod_info; break; } } /* * Check to see if already loaded. This might happen if we * were already loaded as a dependency. */ if ((mod_loaded = module_lookup(name)) != NULL) { KASSERT(mod == NULL); if (modp) *modp = mod_loaded; return 0; } /* Note! This is from TAILQ, not immediate above */ if (mi == NULL) { /* * XXX: We'd like to panic here, but currently in some * cases (such as nfsserver + nfs), the dependee can be * succesfully linked without the dependencies. */ module_error("can't find builtin dependency `%s'", name); return ENOENT; } /* * Initialize pre-requisites. */ if (mi->mi_required != NULL) { for (s = mi->mi_required; *s != '\0'; s = p) { if (*s == ',') s++; p = s; while (*p != '\0' && *p != ',') p++; len = min(p - s + 1, sizeof(buf)); strlcpy(buf, s, len); if (buf[0] == '\0') break; if (mod->mod_nrequired == MAXMODDEPS - 1) { module_error("too many required modules " "%d >= %d", mod->mod_nrequired, MAXMODDEPS - 1); return EINVAL; } error = module_do_builtin(buf, &mod2, NULL); if (error != 0) { return error; } mod->mod_required[mod->mod_nrequired++] = mod2; } } /* * Try to initialize the module. */ prev_active = module_active; module_active = mod; error = (*mi->mi_modcmd)(MODULE_CMD_INIT, props); module_active = prev_active; if (error != 0) { module_error("builtin module `%s' " "failed to init, error %d", mi->mi_name, error); return error; } /* load always succeeds after this point */ TAILQ_REMOVE(&module_builtins, mod, mod_chain); module_builtinlist--; if (modp != NULL) { *modp = mod; } module_enqueue(mod); return 0; } /* * module_do_load: * * Helper routine: load a module from the file system, or one * pushed by the boot loader. */ static int module_do_load(const char *name, bool isdep, int flags, prop_dictionary_t props, module_t **modp, modclass_t class, bool autoload) { #define MODULE_MAX_DEPTH 6 TAILQ_HEAD(pending_t, module); static int depth = 0; static struct pending_t *pending_lists[MODULE_MAX_DEPTH]; struct pending_t *pending; struct pending_t new_pending = TAILQ_HEAD_INITIALIZER(new_pending); modinfo_t *mi; module_t *mod, *mod2, *prev_active; prop_dictionary_t filedict; char buf[MAXMODNAME]; const char *s, *p; int error; size_t len; KASSERT(kernconfig_is_held()); filedict = NULL; error = 0; /* * Avoid recursing too far. */ if (++depth > MODULE_MAX_DEPTH) { module_error("recursion too deep for `%s' %d > %d", name, depth, MODULE_MAX_DEPTH); depth--; return EMLINK; } /* * Set up the pending list for this depth. If this is a * recursive entry, then use same list as for outer call, * else use the locally allocated list. In either case, * remember which one we're using. */ if (isdep) { KASSERT(depth > 1); pending = pending_lists[depth - 2]; } else pending = &new_pending; pending_lists[depth - 1] = pending; /* * Search the list of disabled builtins first. */ TAILQ_FOREACH(mod, &module_builtins, mod_chain) { if (strcmp(mod->mod_info->mi_name, name) == 0) { break; } } if (mod) { if ((mod->mod_flags & MODFLG_MUST_FORCE) && (flags & MODCTL_LOAD_FORCE) == 0) { if (!autoload) { module_error("use -f to reinstate " "builtin module `%s'", name); } depth--; return EPERM; } else { error = module_do_builtin(name, modp, props); depth--; return error; } } /* * Load the module and link. Before going to the file system, * scan the list of modules loaded by the boot loader. */ TAILQ_FOREACH(mod, &module_bootlist, mod_chain) { if (strcmp(mod->mod_info->mi_name, name) == 0) { TAILQ_REMOVE(&module_bootlist, mod, mod_chain); break; } } if (mod != NULL) { TAILQ_INSERT_TAIL(pending, mod, mod_chain); } else { /* * If a requisite module, check to see if it is * already present. */ if (isdep) { mod = module_lookup(name); if (mod != NULL) { if (modp != NULL) { *modp = mod; } depth--; return 0; } } mod = module_newmodule(MODULE_SOURCE_FILESYS); if (mod == NULL) { module_error("out of memory for `%s'", name); depth--; return ENOMEM; } error = module_load_vfs_vec(name, flags, autoload, mod, &filedict); if (error != 0) { #ifdef DEBUG /* * The exec class of modules contains a list of * modules that is the union of all the modules * available for each architecture, so we don't * print an error if they are missing. */ if (class != MODULE_CLASS_EXEC || error != ENOENT) module_error("vfs load failed for `%s', " "error %d", name, error); #endif kmem_free(mod, sizeof(*mod)); depth--; return error; } TAILQ_INSERT_TAIL(pending, mod, mod_chain); error = module_fetch_info(mod); if (error != 0) { module_error("cannot fetch info for `%s', error %d", name, error); goto fail; } } /* * Check compatibility. */ mi = mod->mod_info; if (strlen(mi->mi_name) >= MAXMODNAME) { error = EINVAL; module_error("module name `%s' longer than %d", mi->mi_name, MAXMODNAME); goto fail; } if (!module_compatible(mi->mi_version, __NetBSD_Version__)) { module_error("module `%s' built for `%d', system `%d'", mi->mi_name, mi->mi_version, __NetBSD_Version__); if ((flags & MODCTL_LOAD_FORCE) != 0) { module_error("forced load, system may be unstable"); } else { error = EPROGMISMATCH; goto fail; } } /* * If a specific kind of module was requested, ensure that we have * a match. */ if (!MODULE_CLASS_MATCH(mi, class)) { module_incompat(mi, class); error = ENOENT; goto fail; } /* * If loading a dependency, `name' is a plain module name. * The name must match. */ if (isdep && strcmp(mi->mi_name, name) != 0) { module_error("dependency name mismatch (`%s' != `%s')", name, mi->mi_name); error = ENOENT; goto fail; } /* * Check to see if the module is already loaded. If so, we may * have been recursively called to handle a dependency, so be sure * to set modp. */ if ((mod2 = module_lookup(mi->mi_name)) != NULL) { if (modp != NULL) *modp = mod2; module_print("module `%s' already loaded", mi->mi_name); error = EEXIST; goto fail; } /* * Block circular dependencies. */ TAILQ_FOREACH(mod2, pending, mod_chain) { if (mod == mod2) { continue; } if (strcmp(mod2->mod_info->mi_name, mi->mi_name) == 0) { error = EDEADLK; module_error("circular dependency detected for `%s'", mi->mi_name); goto fail; } } /* * Now try to load any requisite modules. */ if (mi->mi_required != NULL) { for (s = mi->mi_required; *s != '\0'; s = p) { if (*s == ',') s++; p = s; while (*p != '\0' && *p != ',') p++; len = p - s + 1; if (len >= MAXMODNAME) { error = EINVAL; module_error("required module name `%s' " "longer than %d", mi->mi_required, MAXMODNAME); goto fail; } strlcpy(buf, s, len); if (buf[0] == '\0') break; if (mod->mod_nrequired == MAXMODDEPS - 1) { error = EINVAL; module_error("too many required modules " "%d >= %d", mod->mod_nrequired, MAXMODDEPS - 1); goto fail; } if (strcmp(buf, mi->mi_name) == 0) { error = EDEADLK; module_error("self-dependency detected for " "`%s'", mi->mi_name); goto fail; } error = module_do_load(buf, true, flags, NULL, &mod2, MODULE_CLASS_ANY, true); if (error != 0) { module_error("recursive load failed for `%s' " "(`%s' required), error %d", mi->mi_name, buf, error); goto fail; } mod->mod_required[mod->mod_nrequired++] = mod2; } } /* * We loaded all needed modules successfully: perform global * relocations and initialize. */ error = kobj_affix(mod->mod_kobj, mi->mi_name); if (error != 0) { /* Cannot touch 'mi' as the module is now gone. */ module_error("unable to affix module `%s', error %d", name, error); goto fail2; } if (filedict) { if (!module_merge_dicts(filedict, props)) { module_error("module properties failed for %s", name); error = EINVAL; goto fail; } } prev_active = module_active; module_active = mod; error = (*mi->mi_modcmd)(MODULE_CMD_INIT, filedict ? filedict : props); module_active = prev_active; if (filedict) { prop_object_release(filedict); filedict = NULL; } if (error != 0) { module_error("modcmd function failed for `%s', error %d", mi->mi_name, error); goto fail; } /* * Good, the module loaded successfully. Put it onto the * list and add references to its requisite modules. */ TAILQ_REMOVE(pending, mod, mod_chain); module_enqueue(mod); if (modp != NULL) { *modp = mod; } if (autoload && module_autotime > 0) { /* * Arrange to try unloading the module after * a short delay unless auto-unload is disabled. */ mod->mod_autotime = time_second + module_autotime; mod->mod_flags |= MODFLG_AUTO_LOADED; module_thread_kick(); } depth--; return 0; fail: kobj_unload(mod->mod_kobj); fail2: if (filedict != NULL) { prop_object_release(filedict); filedict = NULL; } TAILQ_REMOVE(pending, mod, mod_chain); kmem_free(mod, sizeof(*mod)); depth--; return error; } /* * module_do_unload: * * Helper routine: do the dirty work of unloading a module. */ static int module_do_unload(const char *name, bool load_requires_force) { module_t *mod, *prev_active; int error; u_int i; KASSERT(kernconfig_is_held()); KASSERT(name != NULL); mod = module_lookup(name); if (mod == NULL) { module_error("module `%s' not found", name); return ENOENT; } if (mod->mod_refcnt != 0) { module_print("module `%s' busy", name); return EBUSY; } /* * Builtin secmodels are there to stay. */ if (mod->mod_source == MODULE_SOURCE_KERNEL && mod->mod_info->mi_class == MODULE_CLASS_SECMODEL) { return EPERM; } prev_active = module_active; module_active = mod; error = (*mod->mod_info->mi_modcmd)(MODULE_CMD_FINI, NULL); module_active = prev_active; if (error != 0) { module_print("cannot unload module `%s' error=%d", name, error); return error; } module_count--; TAILQ_REMOVE(&module_list, mod, mod_chain); for (i = 0; i < mod->mod_nrequired; i++) { mod->mod_required[i]->mod_refcnt--; } module_print("unloaded module `%s'", name); if (mod->mod_kobj != NULL) { kobj_unload(mod->mod_kobj); } if (mod->mod_source == MODULE_SOURCE_KERNEL) { mod->mod_nrequired = 0; /* will be re-parsed */ if (load_requires_force) module_require_force(mod); TAILQ_INSERT_TAIL(&module_builtins, mod, mod_chain); module_builtinlist++; } else { kmem_free(mod, sizeof(*mod)); } module_gen++; return 0; } /* * module_prime: * * Push a module loaded by the bootloader onto our internal * list. */ int module_prime(const char *name, void *base, size_t size) { module_t *mod; int error; mod = module_newmodule(MODULE_SOURCE_BOOT); if (mod == NULL) { return ENOMEM; } error = kobj_load_mem(&mod->mod_kobj, name, base, size); if (error != 0) { kmem_free(mod, sizeof(*mod)); module_error("unable to load `%s' pushed by boot loader, " "error %d", name, error); return error; } error = module_fetch_info(mod); if (error != 0) { kobj_unload(mod->mod_kobj); kmem_free(mod, sizeof(*mod)); module_error("unable to load `%s' pushed by boot loader, " "error %d", name, error); return error; } TAILQ_INSERT_TAIL(&module_bootlist, mod, mod_chain); return 0; } /* * module_fetch_into: * * Fetch modinfo record from a loaded module. */ static int module_fetch_info(module_t *mod) { int error; void *addr; size_t size; /* * Find module info record and check compatibility. */ error = kobj_find_section(mod->mod_kobj, "link_set_modules", &addr, &size); if (error != 0) { module_error("`link_set_modules' section not present, " "error %d", error); return error; } if (size != sizeof(modinfo_t **)) { module_error("`link_set_modules' section wrong size %zu != %zu", size, sizeof(modinfo_t **)); return ENOEXEC; } mod->mod_info = *(modinfo_t **)addr; return 0; } /* * module_find_section: * * Allows a module that is being initialized to look up a section * within its ELF object. */ int module_find_section(const char *name, void **addr, size_t *size) { KASSERT(kernconfig_is_held()); KASSERT(module_active != NULL); return kobj_find_section(module_active->mod_kobj, name, addr, size); } /* * module_thread: * * Automatically unload modules. We try once to unload autoloaded * modules after module_autotime seconds. If the system is under * severe memory pressure, we'll try unloading all modules, else if * module_autotime is zero, we don't try to unload, even if the * module was previously scheduled for unload. */ static void module_thread(void *cookie) { module_t *mod, *next; modinfo_t *mi; int error; for (;;) { kernconfig_lock(); for (mod = TAILQ_FIRST(&module_list); mod != NULL; mod = next) { next = TAILQ_NEXT(mod, mod_chain); /* skip built-in modules */ if (mod->mod_source == MODULE_SOURCE_KERNEL) continue; /* skip modules that weren't auto-loaded */ if ((mod->mod_flags & MODFLG_AUTO_LOADED) == 0) continue; if (uvmexp.free < uvmexp.freemin) { module_thread_ticks = hz; } else if (module_autotime == 0 || mod->mod_autotime == 0) { continue; } else if (time_second < mod->mod_autotime) { module_thread_ticks = hz; continue; } else { mod->mod_autotime = 0; } /* * If this module wants to avoid autounload then * skip it. Some modules can ping-pong in and out * because their use is transient but often. * Example: exec_script. */ mi = mod->mod_info; error = (*mi->mi_modcmd)(MODULE_CMD_AUTOUNLOAD, NULL); if (error == 0 || error == ENOTTY) { (void)module_do_unload(mi->mi_name, false); } } kernconfig_unlock(); mutex_enter(&module_thread_lock); (void)cv_timedwait(&module_thread_cv, &module_thread_lock, module_thread_ticks); module_thread_ticks = 0; mutex_exit(&module_thread_lock); } } /* * module_thread: * * Kick the module thread into action, perhaps because the * system is low on memory. */ void module_thread_kick(void) { mutex_enter(&module_thread_lock); module_thread_ticks = hz; cv_broadcast(&module_thread_cv); mutex_exit(&module_thread_lock); } #ifdef DDB /* * module_whatis: * * Helper routine for DDB. */ void module_whatis(uintptr_t addr, void (*pr)(const char *, ...)) { module_t *mod; size_t msize; vaddr_t maddr; TAILQ_FOREACH(mod, &module_list, mod_chain) { if (mod->mod_kobj == NULL) { continue; } if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) continue; if (addr < maddr || addr >= maddr + msize) { continue; } (*pr)("%p is %p+%zu, in kernel module `%s'\n", (void *)addr, (void *)maddr, (size_t)(addr - maddr), mod->mod_info->mi_name); } } /* * module_print_list: * * Helper routine for DDB. */ void module_print_list(void (*pr)(const char *, ...)) { const char *src; module_t *mod; size_t msize; vaddr_t maddr; (*pr)("%16s %16s %8s %8s\n", "NAME", "TEXT/DATA", "SIZE", "SOURCE"); TAILQ_FOREACH(mod, &module_list, mod_chain) { switch (mod->mod_source) { case MODULE_SOURCE_KERNEL: src = "builtin"; break; case MODULE_SOURCE_FILESYS: src = "filesys"; break; case MODULE_SOURCE_BOOT: src = "boot"; break; default: src = "unknown"; break; } if (mod->mod_kobj == NULL) { maddr = 0; msize = 0; } else if (kobj_stat(mod->mod_kobj, &maddr, &msize) != 0) continue; (*pr)("%16s %16lx %8ld %8s\n", mod->mod_info->mi_name, (long)maddr, (long)msize, src); } } #endif /* DDB */ static bool module_merge_dicts(prop_dictionary_t existing_dict, const prop_dictionary_t new_dict) { prop_dictionary_keysym_t props_keysym; prop_object_iterator_t props_iter; prop_object_t props_obj; const char *props_key; bool error; if (new_dict == NULL) { /* nothing to merge */ return true; } error = false; props_iter = prop_dictionary_iterator(new_dict); if (props_iter == NULL) { return false; } while ((props_obj = prop_object_iterator_next(props_iter)) != NULL) { props_keysym = (prop_dictionary_keysym_t)props_obj; props_key = prop_dictionary_keysym_cstring_nocopy(props_keysym); props_obj = prop_dictionary_get_keysym(new_dict, props_keysym); if ((props_obj == NULL) || !prop_dictionary_set(existing_dict, props_key, props_obj)) { error = true; goto out; } } error = false; out: prop_object_iterator_release(props_iter); return !error; }