From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38461) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XrZVx-0000y8-Le for qemu-devel@nongnu.org; Thu, 20 Nov 2014 16:43:50 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XrZVs-0005Um-Ko for qemu-devel@nongnu.org; Thu, 20 Nov 2014 16:43:45 -0500 Received: from mx1.redhat.com ([209.132.183.28]:34355) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XrZVs-0005UF-DO for qemu-devel@nongnu.org; Thu, 20 Nov 2014 16:43:40 -0500 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id sAKLhdd5022884 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL) for ; Thu, 20 Nov 2014 16:43:39 -0500 Message-ID: <546E608A.60507@redhat.com> Date: Thu, 20 Nov 2014 14:43:38 -0700 From: Eric Blake MIME-Version: 1.0 References: <1416503198-17031-1-git-send-email-mreitz@redhat.com> <1416503198-17031-7-git-send-email-mreitz@redhat.com> In-Reply-To: <1416503198-17031-7-git-send-email-mreitz@redhat.com> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="H0ANwgLnIEp4B9SuUS46RcujpmVkuBisM" Subject: Re: [Qemu-devel] [PATCH v3 06/22] qcow2: Helper for refcount array reallocation List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Max Reitz , qemu-devel@nongnu.org Cc: Kevin Wolf , Stefan Hajnoczi This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --H0ANwgLnIEp4B9SuUS46RcujpmVkuBisM Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On 11/20/2014 10:06 AM, Max Reitz wrote: > Add a helper function for reallocating a refcount array, independent of= > the refcount order. The newly allocated space is zeroed and the functio= n > handles failed reallocations gracefully. >=20 > The helper function will always align the buffer size to a cluster > boundary; if storing the refcounts in such an array in big endian byte > order, this makes it possible to write parts of the array directly as > refcount blocks into the image file. >=20 > Signed-off-by: Max Reitz > Reviewed-by: Eric Blake Perhaps the changes since v2 warranted removing my earlier R-b to make sure I review closely? > --- > block/qcow2-refcount.c | 135 +++++++++++++++++++++++++++++++----------= -------- > 1 file changed, 86 insertions(+), 49 deletions(-) >=20 > +static int realloc_refcount_array(BDRVQcowState *s, uint16_t **array, > + int64_t *size, int64_t new_size) > +{ > + /* Round to clusters so the array can be directly written to disk = */ > + size_t old_byte_size =3D ROUND_UP(refcount_array_byte_size(s, *siz= e), > + s->cluster_size); > + size_t new_byte_size =3D ROUND_UP(refcount_array_byte_size(s, new_= size), > + s->cluster_size); > + uint16_t *new_ptr; > + > + if (new_byte_size <=3D old_byte_size) { > + *size =3D new_size; > + return 0; > + } > + > + assert(new_byte_size > 0); Should this assert be moved before the early exit? Hmm, that's my only finding, and you did incorporate improvements mostly to comments or asserts as compared to v2. Moving the assert is small enough, and not a show-stopper if you leave it in place, so: Reviewed-by: Eric Blake --=20 Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org --H0ANwgLnIEp4B9SuUS46RcujpmVkuBisM Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: Public key at http://people.redhat.com/eblake/eblake.gpg iQEcBAEBCAAGBQJUbmCKAAoJEKeha0olJ0NqT6EH/RJezaeeDI6UEiBR+szk8Bgm 81ECXX4F+YHe0jv6tkXcWfN2GuaOcX7yNypkf/ZSAAXBWVd1hY0eCpfW5lzAE6we opRqiNliWHB7YMhgkFQeXH3e2gdBP7uKn8UiM68GSV3AKMpJEBj++uysQyVJIYiK alqGtHTBMHnZGxcK4OfinCitbQcpM80si+G50glhqvGhm81epZLhQ25h4G6lHGAf MNo702le5U6zgDbM2WCCjv86W9AiOovBf8z30QBem3y9GL9hrs2lTtJL6O/4jsJ+ 3w+B/tvlYs82VaQZcHHsVqAsZhj4SbNvP9DVSrDNE9j56WnXs463CTKXITn4BqQ= =BoLt -----END PGP SIGNATURE----- --H0ANwgLnIEp4B9SuUS46RcujpmVkuBisM--