On Tue, Jul 16, 2013 at 06:29:11PM +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 > > v1->v2: see patches 1, 6, 9, 10, 11, 12 > > 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 | 23 ++++- > block/vvfat.c | 15 ++-- > include/block/block.h | 34 +++++-- > include/block/block_int.h | 2 +- > qemu-img-cmds.hx | 6 ++ > qemu-img.c | 225 > +++++++++++++++++++++++++++++++++++++++++----- > 18 files changed, 503 insertions(+), 183 deletions(-)
Applied s/MAX/MIN/ fixup suggested by Fam. Thanks, applied to my block tree: https://github.com/stefanha/qemu/commits/block Stefan
