| Message ID | 20230324090605.28361-1-faithilikerun@gmail.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | Add support for zoned device | expand |
Hi Sam, On 24/3/23 10:05, Sam Li wrote: > Zoned Block Devices (ZBDs) devide the LBA space to block regions called zones > that are larger than the LBA size. It can only allow sequential writes, which > reduces write amplification in SSD, leading to higher throughput and increased > capacity. More details about ZBDs can be found at: > > https://zonedstorage.io/docs/introduction/zoned-storage > > The zoned device support aims to let guests (virtual machines) access zoned > storage devices on the host (hypervisor) through a virtio-blk device. This > involves extending QEMU's block layer and virtio-blk emulation code. In its > current status, the virtio-blk device is not aware of ZBDs but the guest sees > host-managed drives as regular drive that will runs correctly under the most > common write workloads. > > This patch series extend the block layer APIs with the minimum set of zoned > commands that are necessary to support zoned devices. The commands are - Report > Zones, four zone operations and Zone Append. > > There has been a debate on whethre introducing new zoned_host_device BlockDriver > specifically for zoned devices. In the end, it's been decided to stick to > existing host_device BlockDriver interface by only adding new zoned operations > inside it. The benefit of that is to avoid further changes - one example is > command line syntax - to the applications like Libvirt using QEMU zoned > emulation. > > It can be tested on a null_blk device using qemu-io or qemu-iotests. For > example, to test zone report using qemu-io: > $ path/to/qemu-io --image-opts -n driver=host_device,filename=/dev/nullb0 > -c "zrp offset nr_zones" Sorry to jump late, but the patch subject prefixes are a bit confusing. Some suggestions: > Sam Li (8): > include: add zoned device structs block/block-common: ... > file-posix: introduce helper functions for sysfs attributes block/file-posix: ... > block: add block layer APIs resembling Linux ZonedBlockDevice ioctls block/block-backend: ... > raw-format: add zone operations to pass through requests block/raw-format: ... > config: add check to block layer block: ... > qemu-iotests: test new zone operations iotests: ... > block: add some trace events for new block layer APIs I'd squash that with patch #4 "block/raw-format: add zone operations to pass through requests". Regards, Phil. > docs/zoned-storage: add zoned device documentation > > block.c | 19 ++ > block/block-backend.c | 133 ++++++++ > block/file-posix.c | 444 +++++++++++++++++++++++-- > block/io.c | 41 +++ > block/raw-format.c | 18 + > block/trace-events | 2 + > docs/devel/zoned-storage.rst | 43 +++ > docs/system/qemu-block-drivers.rst.inc | 6 + > include/block/block-common.h | 43 +++ > include/block/block-io.h | 9 + > include/block/block_int-common.h | 29 ++ > include/block/raw-aio.h | 6 +- > include/sysemu/block-backend-io.h | 18 + > meson.build | 4 + > qemu-io-cmds.c | 149 +++++++++ > tests/qemu-iotests/tests/zoned | 89 +++++ > tests/qemu-iotests/tests/zoned.out | 53 +++ > 17 files changed, 1069 insertions(+), 37 deletions(-) > create mode 100644 docs/devel/zoned-storage.rst > create mode 100755 tests/qemu-iotests/tests/zoned > create mode 100644 tests/qemu-iotests/tests/zoned.out >
Thanks, applied with Philippe's suggested commit message changes: https://gitlab.com/stefanha/qemu/-/tree/block-next I left the trace events commit separate. Stefan