Add qemu 2.4.0

[kvmfornfv.git] / qemu / util / module.c

diff --git a/qemu/util/module.c b/qemu/util/module.c
new file mode 100644 (file)
index 0000000..4bd4a94
--- /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
+}