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Date: Fri, 14 Mar 2014 04:51:05 +0000
From: Al Viro <viro@ZenIV.linux.org.uk>
To: NeilBrown <neilb@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
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Subject: Re: [PATCH] fs: fix i_writecount on shmem and friends
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On Thu, Mar 13, 2014 at 04:55:41PM +1100, NeilBrown wrote:

> Can we do direct writes from kernel space yet?  If so I'll change the code to
> do that so that it will work with any filesystem (which supports direct
> writes).

You can - see __swap_writepage() (mm/page_io.c).  However, that area is
about to get a lot of massage, so it would make sense to wait a bit...

> (The documentation says we that bitmap files should only be used on ext2 or
> ext3.  Most people use bitmaps on the raw devices so hopefully the few who
> have a need for files will read the documentation :-)
> 
> (and yes, I check for FMODE_WRITE)

Umm...  Where?