[PATCH RFC 00/15] vhost-user: isolated memory

This patch series implements a memory isolation mode in vhost-user. The
purpose of this mode is to provide the option of additional security by
eliminating direct access of guest memory by vhost-user devices.
At a high level this works by:

1. Adding qdev and qapi properties required to enable isolation mode for
   various devices.
2. Allocating an isolation memory region in an anonymous file and mapping it
   to host memory.  This isolation region will hold the bounce buffers and
   vrings necessary to move data.
3. Using a vhost-iova-tree to allocate and track the mapping between
   guest regions and their corresponding bounce buffers in the isolation
   memory.
4. Creating shadow virtqueues to intercept request notifications.  As
   kick and call events are received by an svq, it copies buffer
   contents and descriptors between isolation and guest memory before
   notifying the backend or guest.   

Note: This project is currently in a partially functional state. For
example, in testing vhost-user-input and a keyboard, keystrokes may
register correctly or be double counted depending on the combination
of backend daemon and guest OS used. However, the desire is to make
this work public at this stage for comment on the overall
approach.

Signed-off-by: Connor Kite <[email protected]>
---
ConKite (2):
      vhost-user: Consolidate chardev property definitions
      vhost-user: Add memory-isolation qdev property to vhost-user devices

Connor Kite (13):
      backends/cryptodev-vhost-user: add memory isolation bool
      net/vhost-user: add memory isolation
      vhost-user: add memory_isolation to VhostUserState
      util/iova-tree: g_tree_foreach wrapper
      hw/virtio: iova_tree_foreach wrapper
      hw/virtio/vhost-shadow-virtqueue: used handler
      hw/virtio/vhost-shadow-virtqueue: specified vring placement
      hw/virtio/vhost-shadow-virtqueue: range boundary in translation
      hw/virtio/vhost-user: create isolation region
      hw/virtio/vhost-user: send isolation regions to device
      hw/virtio/vhost-user: add shadow virtqueues and eventfd intercepts
      hw/virtio/vhost-user: handle data movement with shadow vqs
      hw/virtio/vhost-user: shadow vq cleanup

 backends/cryptodev-vhost-user.c      |  24 +-
 backends/vhost-user.c                |   4 +-
 hw/block/vhost-user-blk.c            |   4 +-
 hw/display/vhost-user-gpu.c          |   4 +-
 hw/scsi/vhost-user-scsi.c            |   4 +-
 hw/virtio/vhost-iova-tree.c          |  15 ++
 hw/virtio/vhost-iova-tree.h          |   3 +
 hw/virtio/vhost-shadow-virtqueue.c   |  30 ++-
 hw/virtio/vhost-shadow-virtqueue.h   |  17 ++
 hw/virtio/vhost-stub.c               |   3 +-
 hw/virtio/vhost-user-base.c          |  13 +-
 hw/virtio/vhost-user-fs.c            |   4 +-
 hw/virtio/vhost-user-gpio.c          |   4 -
 hw/virtio/vhost-user-i2c.c           |   5 -
 hw/virtio/vhost-user-input.c         |   5 -
 hw/virtio/vhost-user-rng.c           |   5 -
 hw/virtio/vhost-user-rtc.c           |   4 -
 hw/virtio/vhost-user-scmi.c          |   4 +-
 hw/virtio/vhost-user-snd.c           |   1 -
 hw/virtio/vhost-user-spi.c           |   5 -
 hw/virtio/vhost-user-test-device.c   |   1 -
 hw/virtio/vhost-user-vsock.c         |   4 +-
 hw/virtio/vhost-user.c               | 441 ++++++++++++++++++++++++++++++++++-
 include/hw/virtio/vhost-user-base.h  |   1 +
 include/hw/virtio/vhost-user-blk.h   |   1 +
 include/hw/virtio/vhost-user-fs.h    |   1 +
 include/hw/virtio/vhost-user-scmi.h  |   1 +
 include/hw/virtio/vhost-user-vsock.h |   1 +
 include/hw/virtio/vhost-user.h       |   6 +-
 include/hw/virtio/virtio-gpu.h       |   1 +
 include/hw/virtio/virtio-scsi.h      |   1 +
 include/qemu/iova-tree.h             |  13 ++
 include/system/vhost-user-backend.h  |   3 +-
 net/passt.c                          |  16 +-
 net/vhost-user.c                     |  11 +-
 qapi/net.json                        |  15 +-
 qapi/qom.json                        |   6 +-
 util/iova-tree.c                     |   5 +
 38 files changed, 622 insertions(+), 64 deletions(-)
---
base-commit: 006a22cb26998998385b104db1ff9466ef2f3153
change-id: 20260604-vhost-user-isolated-memory-070ed4833ee7

Best regards,
-- 
Connor Kite <[email protected]>