linux-kernel - Re: [PATCH RFC 1/3] vfs: add copy_file

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20150414200418.GA24660@lenny.home.zabbo.net>
Date:	Tue, 14 Apr 2015 13:04:18 -0700
From:	Zach Brown <zab@...hat.com>
To:	Christoph Hellwig <hch@...radead.org>
Cc:	"J. Bruce Fields" <bfields@...ldses.org>,
	Anna Schumaker <Anna.Schumaker@...app.com>,
	Jeff Layton <jlayton@...chiereds.net>,
	Trond Myklebust <trond.myklebust@...marydata.com>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Linux FS-devel Mailing List <linux-fsdevel@...r.kernel.org>,
	linux-btrfs@...r.kernel.org,
	Linux NFS Mailing List <linux-nfs@...r.kernel.org>,
	linux-scsi@...r.kernel.org
Subject: Re: [PATCH RFC 1/3] vfs: add copy_file_range syscall and vfs helper

On Tue, Apr 14, 2015 at 12:23:25PM -0700, Christoph Hellwig wrote:
> On Tue, Apr 14, 2015 at 11:54:08AM -0700, Zach Brown wrote:
> > Is this relying on btrfs range cloning being atomic?  It certainly
> > doesn't look atomic.  It can modify items across an arbitrarily large
> > number of leaf blocks.  It can make the changes across multiple
> > transactions which could introduce partial modification on reboot after
> > crashes.  It can fail (the dynamic duo: enomem, eio) and leave the
> > desintation partially modified.
> 
> I didn't mean atomic in the failure atomic sense, but in the sense of
> being atomic vs other writes, similar to how Posix specifies it for
> writes vs other writes.  Guess I need to express this intent better.

Ah, right, OK.

- z
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/