}
/* Module a uses b: caller needs module_mutex() */
-int use_module(struct module *a, struct module *b)
+int ref_module(struct module *a, struct module *b)
{
int err;
- if (b == NULL || already_uses(a, b)) return 1;
-
- /* If we're interrupted or time out, we fail. */
- if (wait_event_interruptible_timeout(
- module_wq, (err = strong_try_module_get(b)) != -EBUSY,
- 30 * HZ) <= 0) {
- printk("%s: gave up waiting for init of module %s.\n",
- a->name, b->name);
+ if (b == NULL || already_uses(a, b))
return 0;
- }
- /* If strong_try_module_get() returned a different error, we fail. */
+ /* If module isn't available, we fail. */
+ err = strong_try_module_get(b);
if (err)
- return 0;
+ return err;
err = add_module_usage(a, b);
if (err) {
module_put(b);
- return 0;
+ return err;
}
- return 1;
+ return 0;
}
-EXPORT_SYMBOL_GPL(use_module);
+EXPORT_SYMBOL_GPL(ref_module);
/* Clear the unload stuff of the module. */
static void module_unload_free(struct module *mod)
/* Store the name of the last unloaded module for diagnostic purposes */
strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
- ddebug_remove_module(mod->name);
free_module(mod);
return 0;
{
}
-int use_module(struct module *a, struct module *b)
+int ref_module(struct module *a, struct module *b)
{
- return strong_try_module_get(b) == 0;
+ return strong_try_module_get(b);
}
-EXPORT_SYMBOL_GPL(use_module);
+EXPORT_SYMBOL_GPL(ref_module);
static inline void module_unload_init(struct module *mod)
{
static const struct kernel_symbol *resolve_symbol(Elf_Shdr *sechdrs,
unsigned int versindex,
const char *name,
- struct module *mod)
+ struct module *mod,
+ char ownername[])
{
struct module *owner;
const struct kernel_symbol *sym;
const unsigned long *crc;
+ int err;
mutex_lock(&module_mutex);
sym = find_symbol(name, &owner, &crc,
!(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
- /* use_module can fail due to OOM,
- or module initialization or unloading */
- if (sym) {
- if (!check_version(sechdrs, versindex, name, mod, crc, owner)
- || !use_module(mod, owner))
- sym = NULL;
+ if (!sym)
+ goto unlock;
+
+ if (!check_version(sechdrs, versindex, name, mod, crc, owner)) {
+ sym = ERR_PTR(-EINVAL);
+ goto getname;
+ }
+
+ err = ref_module(mod, owner);
+ if (err) {
+ sym = ERR_PTR(err);
+ goto getname;
}
+
+getname:
+ /* We must make copy under the lock if we failed to get ref. */
+ strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
+unlock:
mutex_unlock(&module_mutex);
return sym;
}
+static const struct kernel_symbol *resolve_symbol_wait(Elf_Shdr *sechdrs,
+ unsigned int versindex,
+ const char *name,
+ struct module *mod)
+{
+ const struct kernel_symbol *ksym;
+ char ownername[MODULE_NAME_LEN];
+
+ if (wait_event_interruptible_timeout(module_wq,
+ !IS_ERR(ksym = resolve_symbol(sechdrs, versindex, name,
+ mod, ownername)) ||
+ PTR_ERR(ksym) != -EBUSY,
+ 30 * HZ) <= 0) {
+ printk(KERN_WARNING "%s: gave up waiting for init of module %s.\n",
+ mod->name, ownername);
+ }
+ return ksym;
+}
+
/*
* /sys/module/foo/sections stuff
* J. Corbet <corbet@lwn.net>
remove_sect_attrs(mod);
mod_kobject_remove(mod);
+ /* Remove dynamic debug info */
+ ddebug_remove_module(mod->name);
+
/* Arch-specific cleanup. */
module_arch_cleanup(mod);
/*
* Ensure that an exported symbol [global namespace] does not already exist
* in the kernel or in some other module's exported symbol table.
+ *
+ * You must hold the module_mutex.
*/
static int verify_export_symbols(struct module *mod)
{
for (i = 0; i < ARRAY_SIZE(arr); i++) {
for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
- const struct kernel_symbol *sym;
-
- /* Stopping preemption makes find_symbol safe. */
- preempt_disable();
- sym = find_symbol(s->name, &owner, NULL, true, false);
- preempt_enable();
-
- if (sym) {
+ if (find_symbol(s->name, &owner, NULL, true, false)) {
printk(KERN_ERR
"%s: exports duplicate symbol %s"
" (owned by %s)\n",
break;
case SHN_UNDEF:
- ksym = resolve_symbol(sechdrs, versindex,
- strtab + sym[i].st_name, mod);
+ ksym = resolve_symbol_wait(sechdrs, versindex,
+ strtab + sym[i].st_name,
+ mod);
/* Ok if resolved. */
- if (ksym) {
+ if (ksym && !IS_ERR(ksym)) {
sym[i].st_value = ksym->value;
break;
}
/* Ok if weak. */
- if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
+ if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
break;
- printk(KERN_WARNING "%s: Unknown symbol %s\n",
- mod->name, strtab + sym[i].st_name);
- ret = -ENOENT;
+ printk(KERN_WARNING "%s: Unknown symbol %s (err %li)\n",
+ mod->name, strtab + sym[i].st_name,
+ PTR_ERR(ksym));
+ ret = PTR_ERR(ksym) ?: -ENOENT;
break;
default:
#endif
}
+static void dynamic_debug_remove(struct _ddebug *debug)
+{
+ if (debug)
+ ddebug_remove_module(debug->modname);
+}
+
static void *module_alloc_update_bounds(unsigned long size)
{
void *ret = module_alloc(size);
void *ptr = NULL; /* Stops spurious gcc warning */
unsigned long symoffs, stroffs, *strmap;
void __percpu *percpu;
+ struct _ddebug *debug = NULL;
+ unsigned int num_debug = 0;
mm_segment_t old_fs;
goto free_mod;
}
- if (find_module(mod->name)) {
- err = -EEXIST;
- goto free_mod;
- }
-
mod->state = MODULE_STATE_COMING;
/* Allow arches to frob section contents and sizes. */
goto cleanup;
}
- /* Find duplicate symbols */
- err = verify_export_symbols(mod);
- if (err < 0)
- goto cleanup;
-
/* Set up and sort exception table */
mod->extable = section_objs(hdr, sechdrs, secstrings, "__ex_table",
sizeof(*mod->extable), &mod->num_exentries);
kfree(strmap);
strmap = NULL;
- if (!mod->taints) {
- struct _ddebug *debug;
- unsigned int num_debug;
-
+ if (!mod->taints)
debug = section_objs(hdr, sechdrs, secstrings, "__verbose",
sizeof(*debug), &num_debug);
- if (debug)
- dynamic_debug_setup(debug, num_debug);
- }
err = module_finalize(hdr, sechdrs, mod);
if (err < 0)
* The mutex protects against concurrent writers.
*/
mutex_lock(&module_mutex);
+ if (find_module(mod->name)) {
+ err = -EEXIST;
+ goto unlock;
+ }
+
+ if (debug)
+ dynamic_debug_setup(debug, num_debug);
+
+ /* Find duplicate symbols */
+ err = verify_export_symbols(mod);
+ if (err < 0)
+ goto ddebug;
+
list_add_rcu(&mod->list, &modules);
mutex_unlock(&module_mutex);
mutex_lock(&module_mutex);
/* Unlink carefully: kallsyms could be walking list. */
list_del_rcu(&mod->list);
+ ddebug:
+ dynamic_debug_remove(debug);
+ unlock:
mutex_unlock(&module_mutex);
synchronize_sched();
module_arch_cleanup(mod);
git://bbs.cooldavid.org / net-next-2.6.git / blobdiff