From mboxrd@z Thu Jan  1 00:00:00 1970
From: Theodore Ts'o <tytso@mit.edu>
Subject: Re: [PATCH 1/2] ext4: introduce new i_write_mutex to protect
 fallocate
Date: Tue, 3 Jun 2014 11:19:58 -0400
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To: Namjae Jeon <namjae.jeon@samsung.com>
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On Tue, Jun 03, 2014 at 03:04:32PM +0900, Namjae Jeon wrote:
> IMHO, If our goal is to solve the problem of xfstests, we can use only
> "ext4: fix ZERO_RANGE test failure in data journalling" patch without
> i_write_mutex patch. And we can add lock for fallocate on next kernel
> after checking with sufficient time.

I thought this patch required i_write_mutex to avoid a race where
another thread modifies an inode while filemap_write_and_wait_range()
is running?

I agree that we could drop the i_write_mutex and add a call to
ext4_force_commit() which should make the xfstest failure rarer, but
the race would still be there, yes?

						- Ted