[PATCH-SERIES v3 pve-storage/qemu-server/pve-qemu] add external qcow2 snapshot support

[Alexandre Derumier]

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.

Changelog v3:
  storage:
    - snapshots files now have the name of the snapshot, and "current" snapshot is the vm volname
    - allow only qcow2 format for base image for simplication
    - merge snapshot code in lvmplugin (qcow2 format auto enable snapshot)
    - the code is a lot more simple now

  qemu-server:
    - convertion -drive to modern -blockdev
      This is needed for blockdev-reopen, where we need to create && switch to snapshot files with same cache,aio,...
      This is also needed to live rename snapshot files (to keep volname for current snapshot)
      I have implemented && tested:
         - disk create,delete,resize,convert,drive_mirror, hotplug,unplug,nbd mirror,cdrom insert/eject
         - block protocol: file,block_device,rbd,nbd,glusterfs
      Note that it's currently incomplete:
         - proxmox backup/restore code need to be converted to blockdev, help is needed
         - iscsi:// path is not yet implemented (I'll look for the v4)
         - efi still in drive format (not blocking, but I'll look for v4)

      The live migration between -drive ---> --blockdev seem to work without breaking, and seem to be 
      transparent for the guest ok, so I think we could try to target pve9 ?



storage.cfg example:

dir: local2
        path /var/liv/vz
        content snippets,vztmpl,backup,images,iso,rootdir
        snapext 1

lvm:test
        vgname test
        content images





pve-storage:

Alexandre Derumier (3):
  qcow2: add external snapshot support
  lvmplugin: add qcow2 snapshot
  storage: vdisk_free: remove external snapshots

 src/PVE/Storage.pm                 |  18 ++-
 src/PVE/Storage/DirPlugin.pm       |   1 +
 src/PVE/Storage/LVMPlugin.pm       | 231 ++++++++++++++++++++++++++---
 src/PVE/Storage/Plugin.pm          | 207 ++++++++++++++++++++++----
 src/test/run_test_zfspoolplugin.pl |  18 +++
 5 files changed, 424 insertions(+), 51 deletions(-)


Alexandre Derumier (11):
  blockdev: cmdline: convert drive to blockdev syntax
  blockdev: fix cfg2cmd tests
  blockdev : convert qemu_driveadd && qemu_drivedel
  blockdev: vm_devices_list : fix block-query
  blockdev: convert cdrom media eject/insert
  blockdev: block_resize: convert to blockdev
  blockdev: nbd_export: block-export-add : use drive-$id for nodename
  blockdev: convert drive_mirror to blockdev_mirror
  blockdev: mirror: change aio on target if io_uring is not default.
  blockdev: add backing_chain support
  qcow2: add external snapshot support

 PVE/QemuConfig.pm                             |   4 +-
 PVE/QemuMigrate.pm                            |   2 +-
 PVE/QemuServer.pm                             | 946 ++++++++++++++----
 test/cfg2cmd/bootorder-empty.conf.cmd         |  12 +-
 test/cfg2cmd/bootorder-legacy.conf.cmd        |  12 +-
 test/cfg2cmd/bootorder.conf.cmd               |  12 +-
 ...putype-icelake-client-deprecation.conf.cmd |   6 +-
 test/cfg2cmd/ide.conf.cmd                     |  23 +-
 test/cfg2cmd/pinned-version-pxe-pve.conf.cmd  |   6 +-
 test/cfg2cmd/pinned-version-pxe.conf.cmd      |   6 +-
 test/cfg2cmd/pinned-version.conf.cmd          |   6 +-
 test/cfg2cmd/q35-ide.conf.cmd                 |  23 +-
 .../q35-linux-hostpci-template.conf.cmd       |   3 +-
 test/cfg2cmd/seabios_serial.conf.cmd          |   6 +-
 ...imple-balloon-free-page-reporting.conf.cmd |   6 +-
 test/cfg2cmd/simple-btrfs.conf.cmd            |   6 +-
 test/cfg2cmd/simple-virtio-blk.conf.cmd       |   6 +-
 test/cfg2cmd/simple1-template.conf.cmd        |  11 +-
 test/cfg2cmd/simple1.conf.cmd                 |   6 +-
 19 files changed, 830 insertions(+), 272 deletions(-)


pve-qemu:

  add block-commit-replaces option patch

 ...052-block-commit-add-replaces-option.patch | 137 ++++++++++++++++++
 debian/patches/series                         |   1 +
 2 files changed, 138 insertions(+)
 create mode 100644 debian/patches/pve/0052-block-commit-add-replaces-option.patch

-- 

2.39.5