/*
* 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"
#ifdef CONFIG_MODULE_UPGRADES
#include "qemu-version.h"
#endif
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 int module_load_file(const char *fname)
{
GModule *g_module;
void (*sym)(void);
const char *dsosuf = HOST_DSOSUF;
int len = strlen(fname);
int suf_len = strlen(dsosuf);
ModuleEntry *e, *next;
int ret;
if (len <= suf_len || strcmp(&fname[len - suf_len], dsosuf)) {
/* wrong suffix */
ret = -EINVAL;
goto out;
}
if (access(fname, F_OK)) {
ret = -ENOENT;
goto out;
}
assert(QTAILQ_EMPTY(&dso_init_list));
g_module = g_module_open(fname, G_MODULE_BIND_LAZY | G_MODULE_BIND_LOCAL);
if (!g_module) {
fprintf(stderr, "Failed to open module: %s\n",
g_module_error());
ret = -EINVAL;
goto out;
}
if (!g_module_symbol(g_module, DSO_STAMP_FUN_STR, (gpointer *)&sym)) {
fprintf(stderr, "Failed to initialize module: %s\n",
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)) {
fprintf(stderr,
"Note: only modules from the same build can be loaded.\n");
}
g_module_close(g_module);
ret = -EINVAL;
} else {
QTAILQ_FOREACH(e, &dso_init_list, node) {
e->init();
register_module_init(e->init, e->type);
}
ret = 0;
}
QTAILQ_FOREACH_SAFE(e, &dso_init_list, node, next) {
QTAILQ_REMOVE(&dso_init_list, e, node);
g_free(e);
}
out:
return ret;
}
#endif
bool module_load_one(const char *prefix, const char *lib_name)
{
bool success = false;
#ifdef CONFIG_MODULES
char *fname = NULL;
char *exec_dir;
#ifdef CONFIG_MODULE_UPGRADES
char *version_dir;
#endif
const char *search_dir;
char *dirs[5];
char *module_name;
int i = 0, n_dirs = 0;
int ret;
static GHashTable *loaded_modules;
if (!g_module_supported()) {
fprintf(stderr, "Module is not supported by system.\n");
return false;
}
if (!loaded_modules) {
loaded_modules = g_hash_table_new(g_str_hash, g_str_equal);
}
module_name = g_strdup_printf("%s%s", prefix, lib_name);
if (!g_hash_table_add(loaded_modules, module_name)) {
g_free(module_name);
return true;
}
exec_dir = qemu_get_exec_dir();
search_dir = getenv("QEMU_MODULE_DIR");
if (search_dir != NULL) {
dirs[n_dirs++] = g_strdup_printf("%s", search_dir);
}
dirs[n_dirs++] = g_strdup_printf("%s", CONFIG_QEMU_MODDIR);
dirs[n_dirs++] = g_strdup_printf("%s/..", exec_dir ? : "");
dirs[n_dirs++] = g_strdup_printf("%s", exec_dir ? : "");
#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));
g_free(exec_dir);
exec_dir = NULL;
for (i = 0; i < n_dirs; i++) {
fname = g_strdup_printf("%s/%s%s",
dirs[i], module_name, HOST_DSOSUF);
ret = module_load_file(fname);
g_free(fname);
fname = NULL;
/* Try loading until loaded a module file */
if (!ret) {
success = true;
break;
}
}
if (!success) {
g_hash_table_remove(loaded_modules, module_name);
g_free(module_name);
}
for (i = 0; i < n_dirs; i++) {
g_free(dirs[i]);
}
#endif
return success;
}
/*
* Building devices and other qom objects modular is mostly useful in
* case they have dependencies to external shared libraries, so we can
* cut down the core qemu library dependencies. Which is the case for
* only a very few devices & objects.
*
* So with the expectation that this will be rather the exception than
* to rule and the list will not gain that many entries go with a
* simple manually maintained list for now.
*/
static struct {
const char *type;
const char *prefix;
const char *module;
} const qom_modules[] = {
{ "ccid-card-passthru", "hw-", "usb-smartcard" },
{ "ccid-card-emulated", "hw-", "usb-smartcard" },
{ "usb-redir", "hw-", "usb-redirect" },
{ "qxl-vga", "hw-", "display-qxl" },
{ "qxl", "hw-", "display-qxl" },
};
static bool module_loaded_qom_all;
void module_load_qom_one(const char *type)
{
int i;
if (module_loaded_qom_all) {
return;
}
for (i = 0; i < ARRAY_SIZE(qom_modules); i++) {
if (strcmp(qom_modules[i].type, type) == 0) {
module_load_one(qom_modules[i].prefix,
qom_modules[i].module);
return;
}
}
}
void module_load_qom_all(void)
{
int i;
if (module_loaded_qom_all) {
return;
}
for (i = 0; i < ARRAY_SIZE(qom_modules); i++) {
if (i > 0 && (strcmp(qom_modules[i - 1].module,
qom_modules[i].module) == 0 &&
strcmp(qom_modules[i - 1].prefix,
qom_modules[i].prefix) == 0)) {
/* one module implementing multiple types -> load only once */
continue;
}
module_load_one(qom_modules[i].prefix, qom_modules[i].module);
}
module_loaded_qom_all = true;
}
