[RFC,v2,0/3] accel/kvm: extend kvm memory listener to support

Message

Emanuele Giuseppe Esposito Sept. 9, 2022, 8:11 a.m. UTC

The aim of this serie is to prepare kvm memory listener to support atomic
memslots update. In order to do that, QEMU should take care of sending all
memslot updates in a single ioctl, so that they can all be processed
atomically.

In order to do that, implement kml->begin() and kml->commit() callbacks, and
change the logic by replacing every ioctl invocation in ->region_* and ->log_*
so that the struct kvm_userspace_memory_region are queued in a linked list that
is then traversed and processed in ->commit.

Patch 1 ensures that ->region_* and ->log_* are always wrapped by ->begin and
->commit.

---
v2:
- remove patch 1, as it is useless
- patch 2: instead of a linked list, use kvm_userspace_memory_region_list
- kvm_userspace_memory_region_list: add padding

Emanuele Giuseppe Esposito (3):
  linux-headers/linux/kvm.h: introduce kvm_userspace_memory_region_list
    ioctl
  accel/kvm/kvm-all.c: pass kvm_userspace_memory_region_entry instead
  kvm/kvm-all.c: listener should delay kvm_vm_ioctl to the commit phase

 accel/kvm/kvm-all.c       | 116 +++++++++++++++++++++++++++++---------
 include/sysemu/kvm_int.h  |   8 +++
 linux-headers/linux/kvm.h |  20 +++++++
 3 files changed, 117 insertions(+), 27 deletions(-)