Commit d5db139a authored by Rusty Russell's avatar Rusty Russell
Browse files

module: make module_refcount() a signed integer. 



James Bottomley points out that it will be -1 during unload.  It's
only used for diagnostics, so let's not hide that as it could be a
clue as to what's gone wrong.

Cc: Jason Wessel <jason.wessel@windriver.com>
Acked-and-documention-added-by: default avatarJames Bottomley <James.Bottomley@HansenPartnership.com>
Reviewed-by: default avatarMasami Hiramatsu <maasami.hiramatsu.pt@hitachi.com>
Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
parent c7496379

include/linux/module.h

+1 −1
Original line number Diff line number Diff line
@@ -444,7 +444,7 @@ extern void __module_put_and_exit(struct module *mod, long code) 
#define module_put_and_exit(code) __module_put_and_exit(THIS_MODULE, code)



#ifdef CONFIG_MODULE_UNLOAD

unsigned long module_refcount(struct module *mod);

int module_refcount(struct module *mod);

void __symbol_put(const char *symbol);

#define symbol_put(x) __symbol_put(VMLINUX_SYMBOL_STR(x))

void symbol_put_addr(void *addr);

kernel/debug/kdb/kdb_main.c

+1 −1
Original line number Diff line number Diff line
@@ -1979,7 +1979,7 @@ static int kdb_lsmod(int argc, const char **argv) 
		kdb_printf("%-20s%8u  0x%p ", mod->name,

			   mod->core_size, (void *)mod);

#ifdef CONFIG_MODULE_UNLOAD

		kdb_printf("%4ld ", module_refcount(mod));

		kdb_printf("%4d ", module_refcount(mod));

#endif

		if (mod->state == MODULE_STATE_GOING)

			kdb_printf(" (Unloading)");

kernel/module.c

+13 −4
Original line number Diff line number Diff line
@@ -772,9 +772,18 @@ static int try_stop_module(struct module *mod, int flags, int *forced) 
	return 0;

}



unsigned long module_refcount(struct module *mod)

/**

 * module_refcount - return the refcount or -1 if unloading

 *

 * @mod:	the module we're checking

 *

 * Returns:

 *	-1 if the module is in the process of unloading

 *	otherwise the number of references in the kernel to the module

 */

int module_refcount(struct module *mod)

{

	return (unsigned long)atomic_read(&mod->refcnt) - MODULE_REF_BASE;

	return atomic_read(&mod->refcnt) - MODULE_REF_BASE;

}

EXPORT_SYMBOL(module_refcount);
@@ -856,7 +865,7 @@ static inline void print_unload_info(struct seq_file *m, struct module *mod) 
	struct module_use *use;

	int printed_something = 0;



	seq_printf(m, " %lu ", module_refcount(mod));

	seq_printf(m, " %i ", module_refcount(mod));



	/*

	 * Always include a trailing , so userspace can differentiate
@@ -908,7 +917,7 @@ EXPORT_SYMBOL_GPL(symbol_put_addr); 
static ssize_t show_refcnt(struct module_attribute *mattr,

			   struct module_kobject *mk, char *buffer)

{

	return sprintf(buffer, "%lu\n", module_refcount(mk->mod));

	return sprintf(buffer, "%i\n", module_refcount(mk->mod));

}



static struct module_attribute modinfo_refcnt =

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