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-rw-r--r--qemu/util/module.c219
1 files changed, 219 insertions, 0 deletions
diff --git a/qemu/util/module.c b/qemu/util/module.c
new file mode 100644
index 000000000..4bd4a94d8
--- /dev/null
+++ b/qemu/util/module.c
@@ -0,0 +1,219 @@
+/*
+ * 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 <stdlib.h>
+#include "qemu-common.h"
+#ifdef CONFIG_MODULES
+#include <gmodule.h>
+#endif
+#include "qemu/queue.h"
+#include "qemu/module.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 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)
+{
+ ModuleTypeList *l;
+
+ init_lists();
+
+ l = &init_type_list[type];
+
+ return l;
+}
+
+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);
+}
+
+static void module_load(module_init_type type);
+
+void module_call_init(module_init_type type)
+{
+ ModuleTypeList *l;
+ ModuleEntry *e;
+
+ module_load(type);
+ l = find_type(type);
+
+ QTAILQ_FOREACH(e, l, node) {
+ e->init();
+ }
+}
+
+#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) {
+ 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
+
+static void module_load(module_init_type type)
+{
+#ifdef CONFIG_MODULES
+ char *fname = NULL;
+ const char **mp;
+ static const char *block_modules[] = {
+ CONFIG_BLOCK_MODULES
+ };
+ char *exec_dir;
+ char *dirs[3];
+ int i = 0;
+ int ret;
+
+ if (!g_module_supported()) {
+ fprintf(stderr, "Module is not supported by system.\n");
+ return;
+ }
+
+ switch (type) {
+ case MODULE_INIT_BLOCK:
+ mp = block_modules;
+ break;
+ default:
+ /* no other types have dynamic modules for now*/
+ return;
+ }
+
+ exec_dir = qemu_get_exec_dir();
+ dirs[i++] = g_strdup_printf("%s", CONFIG_QEMU_MODDIR);
+ dirs[i++] = g_strdup_printf("%s/..", exec_dir ? : "");
+ dirs[i++] = g_strdup_printf("%s", exec_dir ? : "");
+ assert(i == ARRAY_SIZE(dirs));
+ g_free(exec_dir);
+ exec_dir = NULL;
+
+ for ( ; *mp; mp++) {
+ for (i = 0; i < ARRAY_SIZE(dirs); i++) {
+ fname = g_strdup_printf("%s/%s%s", dirs[i], *mp, HOST_DSOSUF);
+ ret = module_load_file(fname);
+ g_free(fname);
+ fname = NULL;
+ /* Try loading until loaded a module file */
+ if (!ret) {
+ break;
+ }
+ }
+ }
+
+ for (i = 0; i < ARRAY_SIZE(dirs); i++) {
+ g_free(dirs[i]);
+ }
+
+#endif
+}