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 to be written) include tracking dirty bitmaps by bytes (it's still one bit per granularity, but now we won't be double-scaling from bytes to sectors to granularity), then replacing bdrv_get_block_status() with a byte based callback in all the drivers. Available as a tag at: git fetch git://repo.or.cz/qemu/ericb.git nbd-byte-allocated-v1 It requires v9 or later of my prior work on blkdebug: https://lists.gnu.org/archive/html/qemu-devel/2017-04/msg01723.html which in turn requires Max's block-next tree: https://lists.gnu.org/archive/html/qemu-devel/2017-04/msg01298.html Eric Blake (17): 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: Switch mirror_cow_align() to byte-based mirror: Switch mirror_do_read() to byte-based mirror: Switch mirror_iteration() to byte-based 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: Make bdrv_is_allocated_above() byte-based include/block/block.h | 6 +- include/block/block_backup.h | 11 +- include/qemu/ratelimit.h | 3 +- block/backup.c | 126 ++++++++---------- block/commit.c | 54 ++++---- block/io.c | 59 +++++---- block/mirror.c | 300 ++++++++++++++++++++++--------------------- block/replication.c | 29 +++-- block/stream.c | 35 +++-- block/vvfat.c | 34 +++-- migration/block.c | 9 +- qemu-img.c | 15 ++- qemu-io-cmds.c | 57 ++++---- block/trace-events | 14 +- 14 files changed, 381 insertions(+), 371 deletions(-) -- 2.9.3
