Commit 12a5dfc9 authored by Greg Kroah-Hartman's avatar Greg Kroah-Hartman
Browse files

greybus: protocol: add a module owner to a protocol 



Now that protocols can be in a module, we need to reference count them
to lock them into memory so they can't be removed while in use.  So add
a module owner structure, and have it automatically be assigned when
registering the protocol.

Signed-off-by: default avatarGreg Kroah-Hartman <greg@kroah.com>
Reviewed-by: default avatarAlex Elder <elder@linaro.org>
parent 1b6ea0db

drivers/staging/greybus/protocol.c

+12 −5
Original line number Diff line number Diff line
@@ -39,13 +39,15 @@ static struct gb_protocol *_gb_protocol_find(u8 id, u8 major, u8 minor) 
	return NULL;

}



int gb_protocol_register(struct gb_protocol *protocol)

int __gb_protocol_register(struct gb_protocol *protocol, struct module *module)

{

	struct gb_protocol *existing;

	u8 id = protocol->id;

	u8 major = protocol->major;

	u8 minor = protocol->minor;



	protocol->owner = module;



	/*

	 * The protocols list is sorted first by protocol id (low to

	 * high), then by major version (high to low), and finally
@@ -92,7 +94,7 @@ int gb_protocol_register(struct gb_protocol *protocol) 


	return 0;

}

EXPORT_SYMBOL_GPL(gb_protocol_register);

EXPORT_SYMBOL_GPL(__gb_protocol_register);



/*

 * De-register a previously registered protocol.
@@ -135,10 +137,14 @@ struct gb_protocol *gb_protocol_get(u8 id, u8 major, u8 minor) 
	spin_lock_irq(&gb_protocols_lock);

	protocol = _gb_protocol_find(id, major, minor);

	if (protocol) {

		if (!try_module_get(protocol->owner)) {

			protocol = NULL;

		} else {

			protocol_count = protocol->count;

			if (protocol_count != U8_MAX)

				protocol->count++;

		}

	}

	spin_unlock_irq(&gb_protocols_lock);



	if (protocol)
@@ -163,6 +169,7 @@ void gb_protocol_put(struct gb_protocol *protocol) 
		protocol_count = protocol->count;

		if (protocol_count)

			protocol->count--;

		module_put(protocol->owner);

	}

	spin_unlock_irq(&gb_protocols_lock);

	if (protocol)

drivers/staging/greybus/protocol.h

+5 −1
Original line number Diff line number Diff line
@@ -34,11 +34,15 @@ struct gb_protocol { 
	gb_connection_init_t	connection_init;

	gb_connection_exit_t	connection_exit;

	gb_request_recv_t	request_recv;

	struct module		*owner;

};



int gb_protocol_register(struct gb_protocol *protocol);

int __gb_protocol_register(struct gb_protocol *protocol, struct module *module);

int gb_protocol_deregister(struct gb_protocol *protocol);



#define gb_protocol_register(protocol) \

	__gb_protocol_register(protocol, THIS_MODULE)



struct gb_protocol *gb_protocol_get(u8 id, u8 major, u8 minor);

void gb_protocol_put(struct gb_protocol *protocol);