123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405 |
- /*
- * QEMU Module Infrastructure
- *
- * Copyright IBM, Corp. 2009
- *
- * Authors:
- * Anthony Liguori <aliguori@us.ibm.com>
- *
- * This work is licensed under the terms of the GNU GPL, version 2. See
- * the COPYING file in the top-level directory.
- *
- * Contributions after 2012-01-13 are licensed under the terms of the
- * GNU GPL, version 2 or (at your option) any later version.
- */
- #include "qemu/osdep.h"
- #ifdef CONFIG_MODULES
- #include <gmodule.h>
- #endif
- #include "qemu/queue.h"
- #include "qemu/module.h"
- #include "qemu/cutils.h"
- #include "qemu/config-file.h"
- #include "qapi/error.h"
- #ifdef CONFIG_MODULE_UPGRADES
- #include "qemu-version.h"
- #endif
- #include "trace.h"
- typedef struct ModuleEntry
- {
- void (*init)(void);
- QTAILQ_ENTRY(ModuleEntry) node;
- module_init_type type;
- } ModuleEntry;
- typedef QTAILQ_HEAD(, ModuleEntry) ModuleTypeList;
- static ModuleTypeList init_type_list[MODULE_INIT_MAX];
- static bool modules_init_done[MODULE_INIT_MAX];
- static ModuleTypeList dso_init_list;
- static void init_lists(void)
- {
- static int inited;
- int i;
- if (inited) {
- return;
- }
- for (i = 0; i < MODULE_INIT_MAX; i++) {
- QTAILQ_INIT(&init_type_list[i]);
- }
- QTAILQ_INIT(&dso_init_list);
- inited = 1;
- }
- static ModuleTypeList *find_type(module_init_type type)
- {
- init_lists();
- return &init_type_list[type];
- }
- void register_module_init(void (*fn)(void), module_init_type type)
- {
- ModuleEntry *e;
- ModuleTypeList *l;
- e = g_malloc0(sizeof(*e));
- e->init = fn;
- e->type = type;
- l = find_type(type);
- QTAILQ_INSERT_TAIL(l, e, node);
- }
- void register_dso_module_init(void (*fn)(void), module_init_type type)
- {
- ModuleEntry *e;
- init_lists();
- e = g_malloc0(sizeof(*e));
- e->init = fn;
- e->type = type;
- QTAILQ_INSERT_TAIL(&dso_init_list, e, node);
- }
- void module_call_init(module_init_type type)
- {
- ModuleTypeList *l;
- ModuleEntry *e;
- if (modules_init_done[type]) {
- return;
- }
- l = find_type(type);
- QTAILQ_FOREACH(e, l, node) {
- e->init();
- }
- modules_init_done[type] = true;
- }
- #ifdef CONFIG_MODULES
- static const QemuModinfo module_info_stub[] = { {
- /* end of list */
- } };
- static const QemuModinfo *module_info = module_info_stub;
- static const char *module_arch;
- void module_init_info(const QemuModinfo *info)
- {
- module_info = info;
- }
- void module_allow_arch(const char *arch)
- {
- module_arch = arch;
- }
- static bool module_check_arch(const QemuModinfo *modinfo)
- {
- if (modinfo->arch) {
- if (!module_arch) {
- /* no arch set -> ignore all */
- return false;
- }
- if (strcmp(module_arch, modinfo->arch) != 0) {
- /* mismatch */
- return false;
- }
- }
- return true;
- }
- /*
- * module_load_dso: attempt to load an existing dso file
- *
- * fname: full pathname of the file to load
- * export_symbols: if true, add the symbols to the global name space
- * errp: error to set.
- *
- * Return value: true on success, false on error, and errp will be set.
- */
- static bool module_load_dso(const char *fname, bool export_symbols,
- Error **errp)
- {
- GModule *g_module;
- void (*sym)(void);
- ModuleEntry *e, *next;
- int flags;
- assert(QTAILQ_EMPTY(&dso_init_list));
- flags = 0;
- if (!export_symbols) {
- flags |= G_MODULE_BIND_LOCAL;
- }
- g_module = g_module_open(fname, flags);
- if (!g_module) {
- error_setg(errp, "failed to open module: %s", g_module_error());
- return false;
- }
- if (!g_module_symbol(g_module, DSO_STAMP_FUN_STR, (gpointer *)&sym)) {
- error_setg(errp, "failed to initialize module: %s", fname);
- /*
- * Print some info if this is a QEMU module (but from different build),
- * this will make debugging user problems easier.
- */
- if (g_module_symbol(g_module, "qemu_module_dummy", (gpointer *)&sym)) {
- error_append_hint(errp,
- "Only modules from the same build can be loaded.\n");
- }
- g_module_close(g_module);
- return false;
- }
- QTAILQ_FOREACH(e, &dso_init_list, node) {
- e->init();
- register_module_init(e->init, e->type);
- }
- trace_module_load_module(fname);
- QTAILQ_FOREACH_SAFE(e, &dso_init_list, node, next) {
- QTAILQ_REMOVE(&dso_init_list, e, node);
- g_free(e);
- }
- return true;
- }
- int module_load(const char *prefix, const char *name, Error **errp)
- {
- int rv = -1;
- #ifdef CONFIG_MODULE_UPGRADES
- char *version_dir;
- #endif
- const char *search_dir;
- char *dirs[5];
- char *module_name;
- int i = 0, n_dirs = 0;
- bool export_symbols = false;
- static GHashTable *loaded_modules;
- const QemuModinfo *modinfo;
- const char **sl;
- if (!g_module_supported()) {
- error_setg(errp, "%s", "this platform does not support GLib modules");
- return -1;
- }
- if (!loaded_modules) {
- loaded_modules = g_hash_table_new(g_str_hash, g_str_equal);
- }
- /* allocate all resources managed by the out: label here */
- module_name = g_strdup_printf("%s%s", prefix, name);
- if (g_hash_table_contains(loaded_modules, module_name)) {
- g_free(module_name);
- return 2; /* module already loaded */
- }
- g_hash_table_add(loaded_modules, module_name);
- search_dir = getenv("QEMU_MODULE_DIR");
- if (search_dir != NULL) {
- dirs[n_dirs++] = g_strdup_printf("%s", search_dir);
- }
- dirs[n_dirs++] = get_relocated_path(CONFIG_QEMU_MODDIR);
- #ifdef CONFIG_MODULE_UPGRADES
- version_dir = g_strcanon(g_strdup(QEMU_PKGVERSION),
- G_CSET_A_2_Z G_CSET_a_2_z G_CSET_DIGITS "+-.~",
- '_');
- dirs[n_dirs++] = g_strdup_printf("/var/run/qemu/%s", version_dir);
- #endif
- assert(n_dirs <= ARRAY_SIZE(dirs));
- /* end of resources managed by the out: label */
- for (modinfo = module_info; modinfo->name != NULL; modinfo++) {
- if (modinfo->arch) {
- if (strcmp(modinfo->name, module_name) == 0) {
- if (!module_check_arch(modinfo)) {
- error_setg(errp, "module arch does not match: "
- "expected '%s', got '%s'", module_arch, modinfo->arch);
- goto out;
- }
- }
- }
- if (modinfo->deps) {
- if (strcmp(modinfo->name, module_name) == 0) {
- /* we depend on other module(s) */
- for (sl = modinfo->deps; *sl != NULL; sl++) {
- int subrv = module_load("", *sl, errp);
- if (subrv <= 0) {
- rv = subrv;
- goto out;
- }
- }
- } else {
- for (sl = modinfo->deps; *sl != NULL; sl++) {
- if (strcmp(module_name, *sl) == 0) {
- /* another module depends on us */
- export_symbols = true;
- }
- }
- }
- }
- }
- for (i = 0; i < n_dirs; i++) {
- char *fname = g_strdup_printf("%s/%s%s",
- dirs[i], module_name, CONFIG_HOST_DSOSUF);
- int ret = access(fname, F_OK);
- if (ret != 0 && (errno == ENOENT || errno == ENOTDIR)) {
- /*
- * if we don't find the module in this dir, try the next one.
- * If we don't find it in any dir, that can be fine too: user
- * did not install the module. We will return 0 in this case
- * with no error set.
- */
- g_free(fname);
- continue;
- } else if (ret != 0) {
- /* most common is EACCES here */
- error_setg_errno(errp, errno, "error trying to access %s", fname);
- } else if (module_load_dso(fname, export_symbols, errp)) {
- rv = 1; /* module successfully loaded */
- }
- g_free(fname);
- goto out;
- }
- rv = 0; /* module not found */
- out:
- if (rv <= 0) {
- g_hash_table_remove(loaded_modules, module_name);
- g_free(module_name);
- }
- for (i = 0; i < n_dirs; i++) {
- g_free(dirs[i]);
- }
- return rv;
- }
- static bool module_loaded_qom_all;
- int module_load_qom(const char *type, Error **errp)
- {
- const QemuModinfo *modinfo;
- const char **sl;
- int rv = 0;
- if (!type) {
- error_setg(errp, "%s", "type is NULL");
- return -1;
- }
- trace_module_lookup_object_type(type);
- for (modinfo = module_info; modinfo->name != NULL; modinfo++) {
- if (!modinfo->objs) {
- continue;
- }
- if (!module_check_arch(modinfo)) {
- continue;
- }
- for (sl = modinfo->objs; *sl != NULL; sl++) {
- if (strcmp(type, *sl) == 0) {
- if (rv > 0) {
- error_setg(errp, "multiple modules providing '%s'", type);
- return -1;
- }
- rv = module_load("", modinfo->name, errp);
- if (rv < 0) {
- return rv;
- }
- }
- }
- }
- return rv;
- }
- void module_load_qom_all(void)
- {
- const QemuModinfo *modinfo;
- Error *local_err = NULL;
- if (module_loaded_qom_all) {
- return;
- }
- for (modinfo = module_info; modinfo->name != NULL; modinfo++) {
- if (!modinfo->objs) {
- continue;
- }
- if (!module_check_arch(modinfo)) {
- continue;
- }
- if (module_load("", modinfo->name, &local_err) < 0) {
- error_report_err(local_err);
- }
- }
- module_loaded_qom_all = true;
- }
- void qemu_load_module_for_opts(const char *group)
- {
- const QemuModinfo *modinfo;
- const char **sl;
- for (modinfo = module_info; modinfo->name != NULL; modinfo++) {
- if (!modinfo->opts) {
- continue;
- }
- for (sl = modinfo->opts; *sl != NULL; sl++) {
- if (strcmp(group, *sl) == 0) {
- Error *local_err = NULL;
- if (module_load("", modinfo->name, &local_err) < 0) {
- error_report_err(local_err);
- }
- }
- }
- }
- }
- #else
- void module_allow_arch(const char *arch) {}
- void qemu_load_module_for_opts(const char *group) {}
- int module_load(const char *prefix, const char *name, Error **errp) { return 2; }
- int module_load_qom(const char *type, Error **errp) { return 2; }
- void module_load_qom_all(void) {}
- #endif
|