From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56716) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Uyz4Y-0003dE-2F for qemu-devel@nongnu.org; Tue, 16 Jul 2013 02:49:21 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Uyz4U-0003jO-RW for qemu-devel@nongnu.org; Tue, 16 Jul 2013 02:49:17 -0400 Received: from mx.ipv6.kamp.de ([2a02:248:0:51::16]:53126 helo=mx01.kamp.de) by eggs.gnu.org with smtp (Exim 4.71) (envelope-from ) id 1Uyz4U-0003jF-GU for qemu-devel@nongnu.org; Tue, 16 Jul 2013 02:49:14 -0400 Message-ID: <51E4ECE9.7050307@kamp.de> Date: Tue, 16 Jul 2013 08:49:13 +0200 From: Peter Lieven MIME-Version: 1.0 References: <1372862071-28225-1-git-send-email-pbonzini@redhat.com> <20130716034140.GB10106@stefanha-thinkpad.redhat.com> In-Reply-To: <20130716034140.GB10106@stefanha-thinkpad.redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 00/17] Add qemu-img subcommand to dump file metadata List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Hajnoczi Cc: kwolf@redhat.com, Paolo Bonzini , qemu-devel@nongnu.org, stefanha@redhat.com On 16.07.2013 05:41, Stefan Hajnoczi wrote: > On Wed, Jul 03, 2013 at 04:34:14PM +0200, Paolo Bonzini wrote: >> This series adds a subcommand to "map" that can dump file metadata. >> Metadata that is dumped includes: >> >> - whether blocks are allocated in bs->file and, if so, where >> >> - whether blocks are zero >> >> - whether data is read from bs or bs->backing_hd >> >> Metadata is dumped for an entire chain of images. One example usage is >> (for non-compressed, non-encrypted images) to transform the metadata >> into a Linux device-mapper setup, and make a qcow2 image available (for >> read only) as a block device. Another possible usage is to determine >> the used areas of a file, and convert it in place to another format. >> Alternatively, the richer data can be used by block jobs to quickly >> determine if a block is zero without reading it. >> >> The patches implement a new operation, bdrv_co_get_block_status, that >> supersedes bdrv_co_is_allocated. The bdrv_is_allocated API is still >> available of course, and implemented on top of the new operation. >> >> Patches 1-3 touch cow, which uses bdrv_co_is_allocated during its reads >> and writes. I optimized it a bit because it was unbearably slow during >> testing. With these patches (also tested with blkverify), booting of >> a cow guest image is not particularly slow. >> >> Patches 4 to 6 clean up the bdrv_is_allocated and bdrv_is_allocated_above >> implementation, eliminating some code duplication. >> >> Patches 7 and 8 tweak bdrv_has_zero_init and its usage in qemu-img in >> a way that helps when implementing the new API. >> >> Patches 9 to 11 implement bdrv_get_block_status and change the formats >> to report all the available information. >> >> Patch 12 adds the "map" subcommand to qemu-img. >> >> Finally, patches 13 to 17 tweak the implementation to extract more >> information from protocols, and combine this information with format >> metadata whenever possible. >> >> Paolo >> >> Paolo Bonzini (17): >> cow: make reads go at a decent speed >> cow: make writes go at a less indecent speed >> cow: do not call bdrv_co_is_allocated >> block: make bdrv_co_is_allocated static >> block: remove bdrv_is_allocated_above/bdrv_co_is_allocated_above >> distinction >> block: expect errors from bdrv_co_is_allocated >> qemu-img: always probe the input image for allocated sectors >> block: make bdrv_has_zero_init return false for copy-on-write-images >> block: introduce bdrv_get_block_status API >> block: define get_block_status return value >> block: return get_block_status data and flags for formats >> qemu-img: add a "map" subcommand >> block: use bdrv_has_zero_init to return BDRV_BLOCK_ZERO >> raw-posix: return get_block_status data and flags >> raw-posix: detect XFS unwritten extents >> block: add default get_block_status implementation for protocols >> block: look for zero blocks in bs->file >> >> block.c | 134 +++++++++++++-------------- >> block/commit.c | 6 +- >> block/cow.c | 90 +++++++++++++------ >> block/mirror.c | 4 +- >> block/qcow.c | 13 ++- >> block/qcow2.c | 24 +++-- >> block/qed.c | 39 ++++++-- >> block/raw-posix.c | 24 +++-- >> block/raw.c | 6 +- >> block/sheepdog.c | 14 +-- >> block/stream.c | 10 +-- >> block/vdi.c | 17 +++- >> block/vmdk.c | 20 ++++- >> block/vvfat.c | 15 ++-- >> include/block/block.h | 31 +++++-- >> include/block/block_int.h | 2 +- >> qemu-img-cmds.hx | 6 ++ >> qemu-img.c | 225 +++++++++++++++++++++++++++++++++++++++++----- >> 18 files changed, 497 insertions(+), 183 deletions(-) > Makes sense to me. I have left a few small comments but nothing major. > > Stefan Paolo, could you respin it once with all the small fixes. I would go over it again after that if you like. Peter