Hi all.
This is a proposal and realization of new NBD meta context:
qemu. (I hope to send corresponding proposal to NBD protocol soon)
New possible queries will look like:
qemu:dirty-bitmap:<export-bitmap-name>
Mapping from export-bitmap-name to BdrvDirtyBitmap is done through qmp
command nbd-server-add-bitmap. For now, only one bitmap export is
allowed per NBD export, however it may be easily improved if needed
(we don't have such cases for now)
Client and testing.
I wrote client code for Virtuozzo, but it turned out to be unused,
actually it's used only for tests. We don't have cases, where we need
to import dirty bitmap through qemu nbd-client. All this done for
exporting dirty bitmaps to the third tool. So, I think, it is not worth
refactoring, rebasing and merging client part upstream, if there are no
real usage cases.
v3:
01: new
02: rewritten to satisfy changes in 03, drop r-b
03: - fix comments
- rewrite nbd_meta_bitmap_query() and rename it to
nbd_meta_qemu_query(): parse 'qemu:dirty-bitmaps:' for LIST
option to represent list of all dirty-bitmap contexts.
- trace points
- s/512/BDRV_SECTOR_SIZE/
drop TODO comment
04: s/2.13/3.0
05: new
v2:
01 from v1 is dropped: actually, we don't need generic namespace
parsing for now (especially, after moving to qemu: namespace, which has
the same length as base:), lets postpone it.
01: Improve comment wording (Eric), add Eric's r-b
02: improve commit message
move NBD_STATE_DIRTY to header
add comment on NBD_MAX_BITMAP_EXTENTS
remove MAX_EXTENT_LENGTH and instead update add_extents() which
uses it
use export_bitmap_context instead of export_bitmap_name to reduce
operations on it
move from qemu-dirty-bitmap to qemu:dirty-bitmap
other way to parse namespace name
handle FLAG_DF
03: Improve specification of new qmp command (Eric)
Vladimir Sementsov-Ogievskiy (5):
nbd/server: fix trace
nbd/server: add nbd_meta_empty_or_pattern helper
nbd/server: implement dirty bitmap export
qapi: new qmp command nbd-server-add-bitmap
docs/interop: add nbd.txt
docs/interop/nbd.txt | 37 ++++++
qapi/block.json | 23 ++++
include/block/nbd.h | 6 +
blockdev-nbd.c | 23 ++++
nbd/server.c | 322 ++++++++++++++++++++++++++++++++++++++++++++++-----
MAINTAINERS | 1 +
6 files changed, 383 insertions(+), 29 deletions(-)
create mode 100644 docs/interop/nbd.txt
--
2.11.1
