From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Siddhartha Jain" <sid@netmagicsolutions.com>
Subject: RE: Write calls
Date: Thu, 24 Jun 2004 14:40:18 +0530
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Thanks for the pointers Jamie.

Can someone tell me how are the functions in fs/read_write.c (do_sync_write,
vfs_write etc) related to functions like ioctl, mmap and aio_write.

In the layered structure, application -> vfs -> FS Layer -> Generic Block
device layer, what call belongs where?

Thanks,

Siddhartha


>-----Original Message-----
>From: linux-fsdevel-owner@vger.kernel.org
>[mailto:linux-fsdevel-owner@vger.kernel.org]On Behalf Of Jamie Lokier
>
>Siddhartha Jain wrote:
>> The objective is to be able to replicate directories.
>
>There was a thread on linux-kernel about this recently.
>Look for "COW files".
>
>What you want to do is not trivial to do correctly.
>mmap() and hard links both make it complicated.
>
>Fortunately there was lots of good design in that thread, and we
>figured out how to do it properly.  It's just waiting for someone to
>implement it properly :)
>
>Meanwhile, a patch is already available which handles simpler cases.
>
>-- Jamie