There are patches floating around to add NBD_CMD_BLOCK_STATUS, but NBD wants to report status on byte granularity (even if the reporting will probably be naturally aligned to sectors or even much higher levels). I've therefore started the task of converting our block status code to report at a byte granularity rather than sectors.
This is part one of that conversion: bdrv_is_allocated(). Other parts still need a v3, but here's the link to their most recent posting: tracking dirty bitmaps by bytes: https://lists.gnu.org/archive/html/qemu-devel/2017-05/msg03859.html replacing bdrv_get_block_status() with a byte based callback in all the drivers: https://lists.gnu.org/archive/html/qemu-devel/2017-04/msg02642.html Available as a tag at: git fetch git://repo.or.cz/qemu/ericb.git nbd-byte-allocated-v3 Depends on Kevin's block branch Changes since v2 are limited to rebase artifacts (Paolo's conversion to thread-safety being the biggest cause of context conflicts, and also affecting patch 12 - but where I think the resolution is sane enough to keep R-b). Added R-b on patches where it has been given, leaving 19/20 as the only unreviewed patch. 001/20:[----] [--] 'blockjob: Track job ratelimits via bytes, not sectors' 002/20:[----] [-C] 'trace: Show blockjob actions via bytes, not sectors' 003/20:[----] [--] 'stream: Switch stream_populate() to byte-based' 004/20:[----] [--] 'stream: Switch stream_run() to byte-based' 005/20:[----] [--] 'commit: Switch commit_populate() to byte-based' 006/20:[----] [--] 'commit: Switch commit_run() to byte-based' 007/20:[----] [-C] 'mirror: Switch MirrorBlockJob to byte-based' 008/20:[----] [--] 'mirror: Switch mirror_do_zero_or_discard() to byte-based' 009/20:[----] [--] 'mirror: Update signature of mirror_clip_sectors()' 010/20:[----] [--] 'mirror: Switch mirror_cow_align() to byte-based' 011/20:[----] [--] 'mirror: Switch mirror_do_read() to byte-based' 012/20:[0012] [FC] 'mirror: Switch mirror_iteration() to byte-based' 013/20:[----] [--] 'block: Drop unused bdrv_round_sectors_to_clusters()' 014/20:[----] [--] 'backup: Switch BackupBlockJob to byte-based' 015/20:[----] [--] 'backup: Switch block_backup.h to byte-based' 016/20:[----] [--] 'backup: Switch backup_do_cow() to byte-based' 017/20:[----] [--] 'backup: Switch backup_run() to byte-based' 018/20:[----] [--] 'block: Make bdrv_is_allocated() byte-based' 019/20:[----] [--] 'block: Minimize raw use of bds->total_sectors' 020/20:[----] [-C] 'block: Make bdrv_is_allocated_above() byte-based' Eric Blake (20): blockjob: Track job ratelimits via bytes, not sectors trace: Show blockjob actions via bytes, not sectors stream: Switch stream_populate() to byte-based stream: Switch stream_run() to byte-based commit: Switch commit_populate() to byte-based commit: Switch commit_run() to byte-based mirror: Switch MirrorBlockJob to byte-based mirror: Switch mirror_do_zero_or_discard() to byte-based mirror: Update signature of mirror_clip_sectors() mirror: Switch mirror_cow_align() to byte-based mirror: Switch mirror_do_read() to byte-based mirror: Switch mirror_iteration() to byte-based block: Drop unused bdrv_round_sectors_to_clusters() backup: Switch BackupBlockJob to byte-based backup: Switch block_backup.h to byte-based backup: Switch backup_do_cow() to byte-based backup: Switch backup_run() to byte-based block: Make bdrv_is_allocated() byte-based block: Minimize raw use of bds->total_sectors block: Make bdrv_is_allocated_above() byte-based include/block/block.h | 10 +- include/block/block_backup.h | 11 +- include/qemu/ratelimit.h | 3 +- block/backup.c | 130 ++++++++----------- block/commit.c | 54 ++++---- block/io.c | 92 +++++++------ block/mirror.c | 302 ++++++++++++++++++++++--------------------- block/replication.c | 29 +++-- block/stream.c | 35 +++-- block/vvfat.c | 34 +++-- migration/block.c | 9 +- qemu-img.c | 15 ++- qemu-io-cmds.c | 70 +++++----- block/trace-events | 14 +- 14 files changed, 397 insertions(+), 411 deletions(-) -- 2.9.4