diff options
Diffstat (limited to 'qemu/util/module.c')
| -rw-r--r-- | qemu/util/module.c | 219 |
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 +} |