Date: Thu, 7 Oct 2004 12:29:52 +0300 From: Andrey Simonenko <simon@comsys.ntu-kpi.kiev.ua> To: hackers@freebsd.org Subject: Re: Where to start for someone new to kernel coding Message-ID: <20041007092952.GA658@pm514-9.comsys.ntu-kpi.kiev.ua> In-Reply-To: <20041006193350.GA8867@rucus.ru.ac.za> References: <20041006193350.GA8867@rucus.ru.ac.za>
next in thread | previous in thread | raw e-mail | index | archive | help
On Wed, Oct 06, 2004 at 09:33:50PM +0200, John Oxley wrote: > > I want to extend the disk quota system: > - Implement a user space daemon to control it. > - Pass control from the kernel to the user space daemon. [skipped] > Is this at all possible, and if so, where should I start looking for > coding with the kernel. Quota checks are implemented in chk*() functions from the sys/ufs/ufs/ufs_quota.c file. If you want to implement your idea as a replacement of existing QUOTA, then you need to modify this file and probably some others. It is also possible to change addresses of these functions, but this is a hack. Another way is using stackable VFS or MAC framework. In these approaches your module will have control before actual FS code is called. And a module can decide what to do: use already loaded own quota policy in the kernel or send a message to a process, which will decide what to do and send a reply back to your module.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20041007092952.GA658>