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Date: Fri, 29 Aug 2014 09:48:01 +0100
From: "Richard W.M. Jones" <rjones@redhat.com>
Message-ID: <20140829084801.GV1302@redhat.com>
References: <cover.1409299732.git.hutao@cn.fujitsu.com>
	<67d97abc587e7c6985166dbe800686938ac8adb5.1409299732.git.hutao@cn.fujitsu.com>
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Subject: Re: [Qemu-devel] [PATCH v13 5/6] raw-posix: Add full preallocation
	option
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To: Hu Tao <hutao@cn.fujitsu.com>
Cc: Kevin Wolf <kwolf@redhat.com>, Fam Zheng <famz@redhat.com>, qemu-devel@nongnu.org, Max Reitz <mreitz@redhat.com>, Stefan Hajnoczi <stefanha@redhat.com>, Yasunori Goto <y-goto@jp.fujitsu.com>

On Fri, Aug 29, 2014 at 04:33:12PM +0800, Hu Tao wrote:
> +    if (prealloc == PREALLOC_MODE_FULL) {
> +        /* posix_fallocate() doesn't set errno. */
> +        result = -posix_fallocate(fd, 0, total_size);
> +        if (result != 0) {

Is it better to test:

  result != ENOSYS && result != EOPNOTSUPP

here?

I think this is definitely the right approach.

Rich.


-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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