[PATCH-SERIES v6 pve-storage/qemu-server/pve-qemu] add external qcow2 snapshot support

Alexandre Derumier alexandre.derumier at groupe-cyllene.com
Tue Jun 3 09:55:35 CEST 2025


This patch series implement qcow2 external snapshot support for files && lvm volumes

The current internal qcow2 snapshots have bad write performance because no metadatas can be preallocated.

This is particulary visible on a shared filesystem like ocfs2 or gfs2.

Also other bugs are freeze/lock reported by users since years on snapshots delete on nfs
(The disk access seem to be frozen during all the delete duration)

This also open doors for remote snapshot export-import for storage replication.

The pve-storage patches applied on top of Fiona qemu_blockdev_options patch series
https://lists.proxmox.com/pipermail/pve-devel/2025-May/071204.html

This new patch series enable blockdev for qemu machine > 10.0 to avoid breaking efidisk and maybe
potential migrations bug

Changelog v6:
     pve-storage:
      - use fiona qemu_blockdev_options patch
      - add helpers for qemu-img call
      - use qemu-img measure for lvm size (including l2_extended=on)
      - add a new helper volume_support_qemu_snapshot
      - fix Fabian requested changes

     qemu-server:
      - enable blockdev for machine version > 10.0
      - move blockdev code in QemuServer/Blockdev.pm
      - use Fiona qemu_blockdev_options patch for storage plugins
      - add raw size for efidisk
      - fix drivedel with backing chain
      - add tests for qemu-img convert, backing chain,....
      - fix Fabian requested changes
     pve-qemu:
      - add a fake 10.0 qemu bump for testing

MAIN TODO:
    - convert/implement all the backup code, dirty bitmap mirro, ...
    - add snapshots tests


pve-storage:

Alexandre Derumier (9):
  common: add qemu_img_create an preallocation_cmd_option
  common: add qemu_img_create_qcow2_backed
  common: add qemu_img_info helper
  common: add qemu_img_measure
  rename_volume: add source && target snap
  storage: volume_snapshot: add $running param + api bump
  qcow2: add external snapshot support
  lvmplugin: add qcow2 snapshot
  storage: add volume_support_qemu_snapshot

 src/PVE/Storage.pm                   |  28 +-
 src/PVE/Storage/BTRFSPlugin.pm       |   2 +-
 src/PVE/Storage/Common.pm            | 175 ++++++++++
 src/PVE/Storage/DirPlugin.pm         |  11 +
 src/PVE/Storage/ESXiPlugin.pm        |   2 +-
 src/PVE/Storage/GlusterfsPlugin.pm   |   2 +-
 src/PVE/Storage/ISCSIDirectPlugin.pm |   2 +-
 src/PVE/Storage/LVMPlugin.pm         | 467 +++++++++++++++++++++++----
 src/PVE/Storage/LvmThinPlugin.pm     |   2 +-
 src/PVE/Storage/PBSPlugin.pm         |   2 +-
 src/PVE/Storage/Plugin.pm            | 339 ++++++++++++++-----
 src/PVE/Storage/RBDPlugin.pm         |   8 +-
 src/PVE/Storage/ZFSPoolPlugin.pm     |   2 +-
 13 files changed, 875 insertions(+), 167 deletions(-)

qemu-server:

Alexandre Derumier (13):
  blockdev: cmdline: add blockdev syntax support
  blockdev: add support for ovmf && efidisk
  blockdev: vm_devices_list : fix block-query
  blockdev: add support to qemu_driveadd && qemu_drivedel
  blockdev: add support to qemu_block_set_io_throttle
  blockdev: add support for cdrom media eject/insert
  blockdev: add support for block_resize
  blockdev: add support for nbd_export: block-export-add
  blockdev: add blockdev_mirror
  blockdev: change aio on target if io_uring is not default.
  qemu_img convert : add external snapshot support
  blockdev: add backing_chain support
  qcow2: add external snapshot support

 PVE/QemuConfig.pm                             |   4 +-
 PVE/QemuMigrate.pm                            |   2 +-
 PVE/QemuServer.pm                             | 761 +++++++++++-------
 PVE/QemuServer/Blockdev.pm                    | 494 ++++++++++++
 PVE/QemuServer/Drive.pm                       | 201 +++++
 PVE/QemuServer/Makefile                       |   1 +
 test/MigrationTest/QemuMigrateMock.pm         |  10 +-
 test/cfg2cmd/bootorder-blockdev.conf          |  15 +
 test/cfg2cmd/bootorder-blockdev.conf.cmd      |  43 +
 test/cfg2cmd/bootorder-empty-blockdev.conf    |  15 +
 .../cfg2cmd/bootorder-empty-blockdev.conf.cmd |  43 +
 test/cfg2cmd/bootorder-empty.conf             |   1 +
 test/cfg2cmd/bootorder-empty.conf.cmd         |   2 +-
 test/cfg2cmd/bootorder-legacy.conf            |   1 +
 test/cfg2cmd/bootorder-legacy.conf.cmd        |   2 +-
 test/cfg2cmd/bootorder.conf                   |   1 +
 test/cfg2cmd/bootorder.conf.cmd               |   2 +-
 .../cputype-icelake-client-deprecation.conf   |   3 -
 ...putype-icelake-client-deprecation.conf.cmd |   7 +-
 .../custom-cpu-model-defaults.conf.cmd        |   2 +-
 test/cfg2cmd/efi-raw-template.conf.cmd        |   7 +-
 test/cfg2cmd/efi-raw.conf                     |   1 +
 test/cfg2cmd/efi-raw.conf.cmd                 |   2 +-
 test/cfg2cmd/efi-secboot-and-tpm-q35.conf.cmd |   7 +-
 test/cfg2cmd/efi-secboot-and-tpm.conf.cmd     |   7 +-
 test/cfg2cmd/efidisk-on-rbd.conf              |   1 +
 test/cfg2cmd/efidisk-on-rbd.conf.cmd          |   2 +-
 test/cfg2cmd/i440fx-viommu-virtio.conf.cmd    |   2 +-
 test/cfg2cmd/ide-blockdev.conf                |  14 +
 test/cfg2cmd/ide-blockdev.conf.cmd            |  46 ++
 test/cfg2cmd/ide.conf                         |   1 +
 test/cfg2cmd/ide.conf.cmd                     |   2 +-
 .../cfg2cmd/memory-hotplug-hugepages.conf.cmd |   2 +-
 test/cfg2cmd/memory-hotplug.conf.cmd          |   2 +-
 test/cfg2cmd/memory-hugepages-1g.conf.cmd     |   2 +-
 test/cfg2cmd/memory-hugepages-2m.conf.cmd     |   2 +-
 test/cfg2cmd/minimal-defaults.conf.cmd        |   2 +-
 test/cfg2cmd/netdev-7.1-multiqueues.conf.cmd  |   2 +-
 test/cfg2cmd/netdev-7.1.conf.cmd              |   2 +-
 test/cfg2cmd/q35-ide-blockdev.conf            |  15 +
 test/cfg2cmd/q35-ide-blockdev.conf.cmd        |  45 ++
 test/cfg2cmd/q35-ide.conf                     |   2 +-
 test/cfg2cmd/q35-ide.conf.cmd                 |   3 +-
 .../q35-linux-hostpci-mapping.conf.cmd        |   7 +-
 .../q35-linux-hostpci-multifunction.conf.cmd  |   7 +-
 .../q35-linux-hostpci-template.conf.cmd       |  10 +-
 ...q35-linux-hostpci-x-pci-overrides.conf.cmd |   9 +-
 test/cfg2cmd/q35-linux-hostpci.conf.cmd       |   7 +-
 test/cfg2cmd/q35-simple.conf.cmd              |   7 +-
 test/cfg2cmd/q35-viommu-intel.conf.cmd        |   2 +-
 test/cfg2cmd/q35-viommu-virtio.conf.cmd       |   2 +-
 test/cfg2cmd/seabios_serial.conf              |   4 -
 test/cfg2cmd/seabios_serial.conf.cmd          |   7 +-
 test/cfg2cmd/sev-es.conf.cmd                  |   7 +-
 test/cfg2cmd/sev-snp.conf.cmd                 |   2 +-
 test/cfg2cmd/sev-std.conf.cmd                 |   7 +-
 test/cfg2cmd/simple-backingchain.conf         |  21 +
 test/cfg2cmd/simple-backingchain.conf.cmd     |  30 +
 test/cfg2cmd/simple-btrfs.conf                |   1 +
 test/cfg2cmd/simple-btrfs.conf.cmd            |   2 +-
 .../simple-disk-passthrough-blockdev.conf     |  15 +
 .../simple-disk-passthrough-blockdev.conf.cmd |  40 +
 test/cfg2cmd/simple-disk-passthrough.conf     |   1 +
 test/cfg2cmd/simple-disk-passthrough.conf.cmd |   2 +-
 test/cfg2cmd/simple-rbd-blockdev.conf         |  15 +
 test/cfg2cmd/simple-rbd-blockdev.conf.cmd     |  38 +
 test/cfg2cmd/simple-rbd.conf                  |   1 +
 test/cfg2cmd/simple-rbd.conf.cmd              |   2 +-
 test/cfg2cmd/simple-virtio-blk-blockdev.conf  |  13 +
 .../simple-virtio-blk-blockdev.conf.cmd       |  35 +
 test/cfg2cmd/simple-virtio-blk.conf           |   1 +
 test/cfg2cmd/simple-virtio-blk.conf.cmd       |   2 +-
 .../simple-zfs-over-iscsi-blockdev.conf       |  14 +
 .../simple-zfs-over-iscsi-blockdev.conf.cmd   |  35 +
 test/cfg2cmd/simple-zfs-over-iscsi.conf       |   1 +
 test/cfg2cmd/simple-zfs-over-iscsi.conf.cmd   |   2 +-
 test/cfg2cmd/simple1-blockdev.conf            |  14 +
 test/cfg2cmd/simple1-blockdev.conf.cmd        |  35 +
 test/cfg2cmd/simple1-template.conf.cmd        |  13 +-
 test/cfg2cmd/simple1.conf                     |   1 +
 test/cfg2cmd/simple1.conf.cmd                 |   2 +-
 test/cfg2cmd/vnc-clipboard-spice.conf.cmd     |   2 +-
 test/cfg2cmd/vnc-clipboard-std.conf.cmd       |   2 +-
 test/run_config2command_tests.pl              |  52 ++
 test/run_qemu_img_convert_tests.pl            |  44 +
 test/snapshot-test.pm                         |   4 +-
 86 files changed, 1905 insertions(+), 394 deletions(-)
 create mode 100644 PVE/QemuServer/Blockdev.pm
 create mode 100644 test/cfg2cmd/bootorder-blockdev.conf
 create mode 100644 test/cfg2cmd/bootorder-blockdev.conf.cmd
 create mode 100644 test/cfg2cmd/bootorder-empty-blockdev.conf
 create mode 100644 test/cfg2cmd/bootorder-empty-blockdev.conf.cmd
 create mode 100644 test/cfg2cmd/ide-blockdev.conf
 create mode 100644 test/cfg2cmd/ide-blockdev.conf.cmd
 create mode 100644 test/cfg2cmd/q35-ide-blockdev.conf
 create mode 100644 test/cfg2cmd/q35-ide-blockdev.conf.cmd
 create mode 100644 test/cfg2cmd/simple-backingchain.conf
 create mode 100644 test/cfg2cmd/simple-backingchain.conf.cmd
 create mode 100644 test/cfg2cmd/simple-disk-passthrough-blockdev.conf
 create mode 100644 test/cfg2cmd/simple-disk-passthrough-blockdev.conf.cmd
 create mode 100644 test/cfg2cmd/simple-rbd-blockdev.conf
 create mode 100644 test/cfg2cmd/simple-rbd-blockdev.conf.cmd
 create mode 100644 test/cfg2cmd/simple-virtio-blk-blockdev.conf
 create mode 100644 test/cfg2cmd/simple-virtio-blk-blockdev.conf.cmd
 create mode 100644 test/cfg2cmd/simple-zfs-over-iscsi-blockdev.conf
 create mode 100644 test/cfg2cmd/simple-zfs-over-iscsi-blockdev.conf.cmd
 create mode 100644 test/cfg2cmd/simple1-blockdev.conf
 create mode 100644 test/cfg2cmd/simple1-blockdev.conf.cmd

pve-qemu:

Alexandre Derumier (1):
  add fake 10.0

 debian/changelog                              |   6 +
 .../extra/0001-bump-version-to-10.0.0.patch   |  19 ++
 ...438a42f7a178504347456b9e50e3d2c50478.patch | 247 ++++++++++++++++++
 ...b0606879ddeddf04bcf8440aabcfe1393b9c.patch | 120 +++++++++
 debian/patches/series                         |   3 +
 5 files changed, 395 insertions(+)
 create mode 100644 debian/patches/extra/0001-bump-version-to-10.0.0.patch
 create mode 100644 debian/patches/extra/0a7c438a42f7a178504347456b9e50e3d2c50478.patch
 create mode 100644 debian/patches/extra/7956b0606879ddeddf04bcf8440aabcfe1393b9c.patch


-- 
2.39.5




More information about the pve-devel mailing list