From: David Howells <dhowells@redhat.com>
To: ronnie sahlberg <ronniesahlberg@gmail.com>
Cc: dhowells@redhat.com, David Disseldorp <ddiss@samba.org>,
David Howells via samba-technical
<samba-technical@lists.samba.org>,
Steve French <sfrench@samba.org>, Jeremy Allison <jra@samba.org>,
linux-cifs@vger.kernel.org, Paulo Alcantara <pc@manguebit.com>
Subject: Re: Bug in Samba's implementation of FSCTL_QUERY_ALLOCATED_RANGES?
Date: Thu, 23 May 2024 07:21:01 +0100 [thread overview]
Message-ID: <476489.1716445261@warthog.procyon.org.uk> (raw)
In-Reply-To: <CAN05THRuP4_7FvOOrTxHcZXC4dWjjqStRLqS7G_iCAwU5MUNwQ@mail.gmail.com>
ronnie sahlberg <ronniesahlberg@gmail.com> wrote:
> On Thu, 23 May 2024 at 14:54, David Disseldorp <ddiss@samba.org> wrote:
> It might be best to just ignore tests that fail in this area. And just
> accept that some things, at best, is a best-effort approximation.
> (as long as dataloss does not happen, of course. That is never acceptable)
> At the end of the day it is a lot of guesswork and trying to fit a
> square peg (unpredictable ntfs behavior) into a round hole (linux vfs
> api).
The problem is that it essentially renders SEEK_DATA/SEEK_HOLE unusable for
applications on cifs. If there's more than one extent above the starting
position, they'll fail with EIO. The only way to do it is to provide for a
sufficiently large buffer to accommodate however many extents that there are
(and there could be millions, in theory) in order to get just the first one.
David
next prev parent reply other threads:[~2024-05-23 6:21 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-05-21 23:53 Bug in Samba's implementation of FSCTL_QUERY_ALLOCATED_RANGES? David Howells
2024-05-22 8:53 ` David Disseldorp
2024-05-22 10:36 ` David Howells
2024-05-23 4:54 ` David Disseldorp
2024-05-23 5:05 ` ronnie sahlberg
2024-05-23 6:21 ` David Howells [this message]
2024-05-23 6:28 ` ronnie sahlberg
2024-05-23 6:36 ` David Howells
2024-05-23 14:29 ` Tom Talpey
2024-05-23 15:28 ` Paulo Alcantara
2024-05-23 22:49 ` Jeremy Allison
2024-05-24 7:45 ` Stefan Metzmacher
2024-08-22 22:26 ` David Howells
2024-08-23 13:20 ` David Disseldorp
2024-08-28 10:25 ` David Howells
2024-08-28 10:55 ` David Disseldorp
2024-08-28 11:52 ` David Howells
2024-08-28 12:57 ` David Disseldorp
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