From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f178.google.com ([209.85.223.178]:35650 "EHLO mail-io0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751478AbbJNTPL (ORCPT ); Wed, 14 Oct 2015 15:15:11 -0400 Subject: Re: [PATCH v5 8/9] vfs: Add vfs_copy_file_range() support for pagecache copies To: Andy Lutomirski , Christoph Hellwig References: <1443634014-3026-1-git-send-email-Anna.Schumaker@Netapp.com> <1443634014-3026-9-git-send-email-Anna.Schumaker@Netapp.com> <20151011142203.GA31867@infradead.org> <20151012231749.GC11398@birch.djwong.org> <561E980C.9010509@Netapp.com> <20151014182701.GC31225@infradead.org> <20151014184946.GA15214@infradead.org> Cc: Anna Schumaker , "Darrick J. Wong" , linux-nfs@vger.kernel.org, Linux btrfs Developers List , Linux FS Devel , Linux API , Zach Brown , Al Viro , Chris Mason , Michael Kerrisk-manpages , andros@netapp.com From: Austin S Hemmelgarn Message-ID: <561EA997.9020402@gmail.com> Date: Wed, 14 Oct 2015 15:14:31 -0400 MIME-Version: 1.0 In-Reply-To: Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-512; boundary="------------ms080307080103030306090407" Sender: linux-btrfs-owner@vger.kernel.org List-ID: This is a cryptographically signed message in MIME format. --------------ms080307080103030306090407 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable On 2015-10-14 14:53, Andy Lutomirski wrote: > On Wed, Oct 14, 2015 at 11:49 AM, Christoph Hellwig = wrote: >> On Wed, Oct 14, 2015 at 11:38:13AM -0700, Andy Lutomirski wrote: >>> One might argue that reflink is like copy + immediate dedupe. >> >> Not, it's not. It's all that and more, because it is an operation tha= t >> is atomic vs other writes to the file and it's an operation that eithe= r >> clones the whole range or nothing. That's a very important difference= =2E > > Fair enough. > > Would copy_file_range without the reflink option removed still be > permitted to link blocks on supported filesystems (btrfs and maybe > XFS)? I would argue that it should have such functionality, but not do so by=20 default (maybe add some option to tell it to ask the FS to accelerate=20 the copy operation?). --------------ms080307080103030306090407 Content-Type: application/pkcs7-signature; name="smime.p7s" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename="smime.p7s" Content-Description: S/MIME Cryptographic Signature MIAGCSqGSIb3DQEHAqCAMIACAQExDzANBglghkgBZQMEAgMFADCABgkqhkiG9w0BBwEAAKCC Brgwgga0MIIEnKADAgECAgMRLfgwDQYJKoZIhvcNAQENBQAweTEQMA4GA1UEChMHUm9vdCBD QTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNp Z25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2VydC5vcmcwHhcN MTUwOTIxMTEzNTEzWhcNMTYwMzE5MTEzNTEzWjBjMRgwFgYDVQQDEw9DQWNlcnQgV29UIFVz ZXIxIzAhBgkqhkiG9w0BCQEWFGFoZmVycm9pbjdAZ21haWwuY29tMSIwIAYJKoZIhvcNAQkB FhNhaGVtbWVsZ0BvaGlvZ3QuY29tMIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEA nQ/81tq0QBQi5w316VsVNfjg6kVVIMx760TuwA1MUaNQgQ3NyUl+UyFtjhpkNwwChjgAqfGd 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<1443634014-3026-9-git-send-email-Anna.Schumaker@Netapp.com> <20151011142203.GA31867@infradead.org> <20151012231749.GC11398@birch.djwong.org> <561E980C.9010509@Netapp.com> <20151014182701.GC31225@infradead.org> <20151014184946.GA15214@infradead.org> Mime-Version: 1.0 Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-512; boundary="------------ms080307080103030306090407" Cc: Anna Schumaker , "Darrick J. Wong" , linux-nfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Linux btrfs Developers List , Linux FS Devel , Linux API , Zach Brown , Al Viro , Chris Mason , Michael Kerrisk-manpages , andros-HgOvQuBEEgTQT0dZR+AlfA@public.gmane.org To: Andy Lutomirski , Christoph Hellwig Return-path: In-Reply-To: Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-fsdevel.vger.kernel.org This is a cryptographically signed message in MIME format. --------------ms080307080103030306090407 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable On 2015-10-14 14:53, Andy Lutomirski wrote: > On Wed, Oct 14, 2015 at 11:49 AM, Christoph Hellwig = wrote: >> On Wed, Oct 14, 2015 at 11:38:13AM -0700, Andy Lutomirski wrote: >>> One might argue that reflink is like copy + immediate dedupe. >> >> Not, it's not. It's all that and more, because it is an operation tha= t >> is atomic vs other writes to the file and it's an operation that eithe= r >> clones the whole range or nothing. That's a very important difference= =2E > > Fair enough. > > Would copy_file_range without the reflink option removed still be > permitted to link blocks on supported filesystems (btrfs and maybe > XFS)? I would argue that it should have such functionality, but not do so by=20 default (maybe add some option to tell it to ask the FS to accelerate=20 the copy operation?). --------------ms080307080103030306090407 Content-Type: application/pkcs7-signature; name="smime.p7s" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename="smime.p7s" Content-Description: S/MIME Cryptographic Signature MIAGCSqGSIb3DQEHAqCAMIACAQExDzANBglghkgBZQMEAgMFADCABgkqhkiG9w0BBwEAAKCC Brgwgga0MIIEnKADAgECAgMRLfgwDQYJKoZIhvcNAQENBQAweTEQMA4GA1UEChMHUm9vdCBD QTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNp Z25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2VydC5vcmcwHhcN MTUwOTIxMTEzNTEzWhcNMTYwMzE5MTEzNTEzWjBjMRgwFgYDVQQDEw9DQWNlcnQgV29UIFVz ZXIxIzAhBgkqhkiG9w0BCQEWFGFoZmVycm9pbjdAZ21haWwuY29tMSIwIAYJKoZIhvcNAQkB FhNhaGVtbWVsZ0BvaGlvZ3QuY29tMIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEA nQ/81tq0QBQi5w316VsVNfjg6kVVIMx760TuwA1MUaNQgQ3NyUl+UyFtjhpkNwwChjgAqfGd LIMTHAdObcwGfzO5uI2o1a8MHVQna8FRsU3QGouysIOGQlX8jFYXMKPEdnlt0GoQcd+BtESr pivbGWUEkPs1CwM6WOrs+09bAJP3qzKIr0VxervFrzrC5Dg9Rf18r9WXHElBuWHg4GYHNJ2V Ab8iKc10h44FnqxZK8RDN8ts/xX93i9bIBmHnFfyNRfiOUtNVeynJbf6kVtdHP+CRBkXCNRZ qyQT7gbTGD24P92PS2UTmDfplSBcWcTn65o3xWfesbf02jF6PL3BCrVnDRI4RgYxG3zFBJuG qvMoEODLhHKSXPAyQhwZINigZNdw5G1NqjXqUw+lIqdQvoPijK9J3eijiakh9u2bjWOMaleI SMRR6XsdM2O5qun1dqOrCgRkM0XSNtBQ2JjY7CycIx+qifJWsRaYWZz0aQU4ZrtAI7gVhO9h pyNaAGjvm7PdjEBiXq57e4QcgpwzvNlv8pG1c/hnt0msfDWNJtl3b6elhQ2Pz4w/QnWifZ8E BrFEmjeeJa2dqjE3giPVWrsH+lOvQQONsYJOuVb8b0zao4vrWeGmW2q2e3pdv0Axzm/60cJQ haZUv8+JdX9ZzqxOm5w5eUQSclt84u+D+hsCAwEAAaOCAVkwggFVMAwGA1UdEwEB/wQCMAAw VgYJYIZIAYb4QgENBEkWR1RvIGdldCB5b3VyIG93biBjZXJ0aWZpY2F0ZSBmb3IgRlJFRSBo ZWFkIG92ZXIgdG8gaHR0cDovL3d3dy5DQWNlcnQub3JnMA4GA1UdDwEB/wQEAwIDqDBABgNV HSUEOTA3BggrBgEFBQcDBAYIKwYBBQUHAwIGCisGAQQBgjcKAwQGCisGAQQBgjcKAwMGCWCG SAGG+EIEATAyBggrBgEFBQcBAQQmMCQwIgYIKwYBBQUHMAGGFmh0dHA6Ly9vY3NwLmNhY2Vy dC5vcmcwMQYDVR0fBCowKDAmoCSgIoYgaHR0cDovL2NybC5jYWNlcnQub3JnL3Jldm9rZS5j cmwwNAYDVR0RBC0wK4EUYWhmZXJyb2luN0BnbWFpbC5jb22BE2FoZW1tZWxnQG9oaW9ndC5j b20wDQYJKoZIhvcNAQENBQADggIBADMnxtSLiIunh/TQcjnRdf63yf2D8jMtYUm4yDoCF++J jCXbPQBGrpCEHztlNSGIkF3PH7ohKZvlqF4XePWxpY9dkr/pNyCF1PRkwxUURqvuHXbu8Lwn 8D3U2HeOEU3KmrfEo65DcbanJCMTTW7+mU9lZICPP7ZA9/zB+L0Gm1UNFZ6AU50N/86vjQfY WgkCd6dZD4rQ5y8L+d/lRbJW7ZGEQw1bSFVTRpkxxDTOwXH4/GpQfnfqTAtQuJ1CsKT12e+H NSD/RUWGTr289dA3P4nunBlz7qfvKamxPymHeBEUcuICKkL9/OZrnuYnGROFwcdvfjGE5iLB kjp/ttrY4aaVW5EsLASNgiRmA6mbgEAMlw3RwVx0sVelbiIAJg9Twzk4Ct6U9uBKiJ8S0sS2 8RCSyTmCRhJs0vvva5W9QUFGmp5kyFQEoSfBRJlbZfGX2ehI2Hi3U2/PMUm2ONuQG1E+a0AP u7I0NJc/Xil7rqR0gdbfkbWp0a+8dAvaM6J00aIcNo+HkcQkUgtfrw+C2Oyl3q8IjivGXZqT 5UdGUb2KujLjqjG91Dun3/RJ/qgQlotH7WkVBs7YJVTCxfkdN36rToPcnMYOI30FWa0Q06gn F6gUv9/mo6riv3A5bem/BdbgaJoPnWQD9D8wSyci9G4LKC+HQAMdLmGoeZfpJzKHMYIE0TCC BM0CAQEwgYAweTEQMA4GA1UEChMHUm9vdCBDQTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNl cnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNpZ25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcN AQkBFhJzdXBwb3J0QGNhY2VydC5vcmcCAxEt+DANBglghkgBZQMEAgMFAKCCAiEwGAYJKoZI hvcNAQkDMQsGCSqGSIb3DQEHATAcBgkqhkiG9w0BCQUxDxcNMTUxMDE0MTkxNDMxWjBPBgkq hkiG9w0BCQQxQgRAJc/10uovbk9IXpTW9kPqxbNs66d74WsV+G4N1N6m8siIwJ2d5u1w6rxS cesxzU2qoKNmGCd1qD8Ub5r+61fgqDBsBgkqhkiG9w0BCQ8xXzBdMAsGCWCGSAFlAwQBKjAL BglghkgBZQMEAQIwCgYIKoZIhvcNAwcwDgYIKoZIhvcNAwICAgCAMA0GCCqGSIb3DQMCAgFA MAcGBSsOAwIHMA0GCCqGSIb3DQMCAgEoMIGRBgkrBgEEAYI3EAQxgYMwgYAweTEQMA4GA1UE ChMHUm9vdCBDQTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlD QSBDZXJ0IFNpZ25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2Vy dC5vcmcCAxEt+DCBkwYLKoZIhvcNAQkQAgsxgYOggYAweTEQMA4GA1UEChMHUm9vdCBDQTEe MBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNpZ25p bmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2VydC5vcmcCAxEt+DAN BgkqhkiG9w0BAQEFAASCAgB+jpxwzwsFYE/4EcSudyc/DtsFxVz6h6vbpDEMGzKHj3PsPb06 auyFaQg9c6S/2ErmE1eCSfpS9VNaJtoe5sSnpI4WQ6/Li7S1P9SM36txm4I1LlbLqp/kWQuS QbExaJGWvZM9Gs6K92BOlteQao0ppVV5J/7QtQ5GSGBADTyNfGbugItMdfLGLPz2ThwaZuD0 HYSbShAz8NBzpj3/iCZM2s3G3cQHXsqpph8vsWlxcM3eMsI64Fj8TR3EJHoaAokBk/jE/Ptb yjqEI8nbNMrUc3Lt6I41eJDZGA/KZdfwQDDkYd+ltb2H2vqL9v/GwtlThsUMrTVpTGJ3vF1u QAho4TqdHxcx9wQcedReNQdf925mNJFrndX/BQc6Xu7MXHYkUl81wFB9PecHCkd9fxen52iV ZiuY9ULYS52PzGTkAEpkhLHUYLFnrgV5nXNf/Ax/j8TEoQ4EL7r8XGQ51g3PuZ4ZUkGkJGB+ zqWs1LET7Jp334m4LF4RI8RXw71YVbGuIX7RJMkO9o4FXK+MT4qYz6LGmKnf+K1FlsbX5CGQ Y8zDbgaEQwv3MEJHtEiJHOy4XchMwVHf4yuqgGXdiN4dcP6zbvukEapBYDowskC46Hhi++u6 /ii0necyvDb3ZUSK2Ofui2XJiDXIbjOlrRmTMNC4rL47u1qrgVEHAu3+TwAAAAAAAA== --------------ms080307080103030306090407--