qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Fam Zheng <famz@redhat.com>
To: Stefan Hajnoczi <stefanha@gmail.com>
Cc: qemu-devel@nongnu.org, Kevin Wolf <kwolf@redhat.com>,
	Stefan Hajnoczi <stefanha@redhat.com>,
	qemu-block@nongnu.org, Peter Lieven <pl@kamp.de>,
	Max Reitz <mreitz@redhat.com>,
	Ronnie Sahlberg <ronniesahlberg@gmail.com>,
	Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [Qemu-devel] [Qemu-block] [RFC PATCH v2 3/7] qcow2: Implement copy offloading
Date: Fri, 27 Apr 2018 14:28:05 +0800	[thread overview]
Message-ID: <20180427062805.GG4217@lemon.usersys.redhat.com> (raw)
In-Reply-To: <20180426153416.GI30991@stefanha-x1.localdomain>

On Thu, 04/26 16:34, Stefan Hajnoczi wrote:
> On Wed, Apr 18, 2018 at 11:04:20AM +0800, Fam Zheng wrote:
> > +static int qcow2_co_copy_range_to(BlockDriverState *bs,
> > +                                  BdrvChild *src, uint64_t src_offset,
> > +                                  BdrvChild *dst, uint64_t dst_offset,
> > +                                  uint64_t bytes, BdrvRequestFlags flags)
> > +{
> 
> In theory this could increment the refcount if src == dst.  It's not
> necessary to go down to leaf nodes if the sharing can be handled at the
> qcow2 L2 table level.

Yes, this is a good optimization to have.

Fam

  reply	other threads:[~2018-04-27  6:28 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-04-18  3:04 [Qemu-devel] [RFC PATCH v2 0/7] qemu-img convert with copy offloading Fam Zheng
2018-04-18  3:04 ` [Qemu-devel] [RFC PATCH v2 1/7] block: Introduce API for " Fam Zheng
2018-04-26 14:57   ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
2018-04-27  5:52     ` Fam Zheng
2018-04-18  3:04 ` [Qemu-devel] [RFC PATCH v2 2/7] raw: Implement " Fam Zheng
2018-04-26 14:57   ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
2018-04-18  3:04 ` [Qemu-devel] [RFC PATCH v2 3/7] qcow2: " Fam Zheng
2018-04-26 15:34   ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
2018-04-27  6:28     ` Fam Zheng [this message]
2018-04-18  3:04 ` [Qemu-devel] [RFC PATCH v2 4/7] file-posix: Implement bdrv_co_copy_range Fam Zheng
2018-05-03  9:25   ` Stefan Hajnoczi
2018-04-18  3:04 ` [Qemu-devel] [RFC PATCH v2 5/7] iscsi: Implement copy offloading Fam Zheng
2018-05-03 10:27   ` Stefan Hajnoczi
2018-05-09  6:30     ` Fam Zheng
2018-04-18  3:04 ` [Qemu-devel] [RFC PATCH v2 6/7] block-backend: Add blk_co_copy_range Fam Zheng
2018-05-03 10:28   ` Stefan Hajnoczi
2018-04-18  3:04 ` [Qemu-devel] [RFC PATCH v2 7/7] qemu-img: Convert with copy offloading Fam Zheng
2018-05-03 10:34   ` Stefan Hajnoczi

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20180427062805.GG4217@lemon.usersys.redhat.com \
    --to=famz@redhat.com \
    --cc=kwolf@redhat.com \
    --cc=mreitz@redhat.com \
    --cc=pbonzini@redhat.com \
    --cc=pl@kamp.de \
    --cc=qemu-block@nongnu.org \
    --cc=qemu-devel@nongnu.org \
    --cc=ronniesahlberg@gmail.com \
    --cc=stefanha@gmail.com \
    --cc=stefanha@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).