Re: [PATCH] synclink_gt add compat_ioctl

[Arnd Bergmann <arnd@arndb.de>]

On Tuesday 08 May 2007, Paul Fulghum wrote:
> make[3]: *** No rule to make target
> `/usr/src/devel/usr/include/linux/.check.synclink.h', needed by
> `__headerscheck'.  Stop.
> 
> linux/kexec.h includes linux/compat.h without a similar error,
> though that is inside of a #ifdef CONFIG_KEXEC
> 
> Moving linux/compat.h from synclink.h to synclink_gt.c
> removes the error.
> 
> This is the last error standing in my way and I'm trying
> to figure out the rules for when and where you are allowed
> to use compat.h, I'm not familiar with the headerscheck
> facility so I'm not sure what it is looking for and the
> error is not very helpful. There is nothing in Documentation
> covering it.

The warning is about the situation that linux/synclink.h gets
installed by make headers_install, but linux/compat.h does not
get installed, so any user program including linux/synclink.h
will fail to build.

To solve this, you can to change include/linux/Kbuild to list
synclink.h as unifdef-y instead of header-y, and put the parts
that you don't want to be in user space inside of #ifdef __KERNEL__.

Alternatively, you can put these kernel-internal definitions into
a private header file in drivers/char that does not get installed
in the first place. That would be particularly useful if you can
also move other parts of linux/synclink.h into the private header,
when they are not part of the external ABI.

	Arnd <><