From: Stefan Richter Date: Thu, 15 Oct 2009 19:16:53 +0000 (+0200) Subject: firewire: cdev: reduce stack usage by ioctl_dispatch X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=b2c0a2ac3e59f4764c59c23bd90b571e44256030;p=openwrt%2Fstaging%2Fblogic.git firewire: cdev: reduce stack usage by ioctl_dispatch Replace a hardcoded buffer size by a sizeof union {}. This shrinks the stack-allocated ioctl argument buffer from 256 to 40 bytes. (This is not much, but subsequent stack usage particularly by the queue_iso ioctl handler adds up.) The new form is also easier to keep up to date than a hardcoded size if more ioctls are added. Signed-off-by: Stefan Richter --- diff --git a/drivers/firewire/core-cdev.c b/drivers/firewire/core-cdev.c index 1accfaf96c6f..e7290928a900 100644 --- a/drivers/firewire/core-cdev.c +++ b/drivers/firewire/core-cdev.c @@ -1299,7 +1299,23 @@ static int (* const ioctl_handlers[])(struct client *client, void *buffer) = { static int dispatch_ioctl(struct client *client, unsigned int cmd, void __user *arg) { - char buffer[256]; + char buffer[sizeof(union { + struct fw_cdev_get_info _00; + struct fw_cdev_send_request _01; + struct fw_cdev_allocate _02; + struct fw_cdev_deallocate _03; + struct fw_cdev_send_response _04; + struct fw_cdev_initiate_bus_reset _05; + struct fw_cdev_add_descriptor _06; + struct fw_cdev_remove_descriptor _07; + struct fw_cdev_create_iso_context _08; + struct fw_cdev_queue_iso _09; + struct fw_cdev_start_iso _0a; + struct fw_cdev_stop_iso _0b; + struct fw_cdev_get_cycle_timer _0c; + struct fw_cdev_allocate_iso_resource _0d; + struct fw_cdev_send_stream_packet _13; + })]; int ret; if (_IOC_TYPE(cmd) != '#' ||