Re: Copy on write hard links?

From: Richard Weinberger
Date: Sun Sep 29 2013 - 03:14:44 EST

On Sun, Sep 29, 2013 at 7:22 AM, Pádraig Brady <P@xxxxxxxxxxxxxx> wrote:
> On 09/25/2013 03:37 PM, richard -rw- weinberger wrote:
>> On Wed, Sep 25, 2013 at 4:28 PM, Thomas Meyer <thomas@xxxxxxxx> wrote:
>>> Am Mittwoch, den 25.09.2013, 08:59 -0500 schrieb Rob Landley:
>>>> On 09/24/2013 01:36:56 PM, Thomas Meyer wrote:
>>>>> Hi,
>>>>> Is there such a thing?
>>>> In the kernel's vfs layer?
>>> Yes, that would be a nice feature!
>> You mean reflinks?
>> Currently only OCFS2 and btrfs support them.
>> Both using a fs specific ioctl().
>> IIRC GNU cp uses the btrfs specific one if the --reflink parameter is used.
> coreutils is waiting for a reflink syscall to materialize
> rather than adding new per filesystem support

Is this the correct link? It's a proposal for a reflink() syscall.
But corrently both OCFS2 and btrfs are using ioctl().

Digging into GNU coreutils shows that their cp's
clone_file() only supports the btrfs ioctl().
I don't know what the GNU folks big plan is, maybe you know more. :-)

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