The shared memory will be created when a post-launched VM which
specified ivshmem v1 device starts, the same shared memory name
will only create a shared memory region.
The shared memory will be removed when all post-launched VMs
that opened it close the shared memory object.
v2: Support one post-launched VM can configure multiple ivshmem
devices
Tracked-On: #4853
Signed-off-by: Yuan Liu <yuan1.liu@intel.com>
Acked-by: Yu Wang <yu1.wang@intel.com>
Support shared memory based inter-vm communication for ACRN
post-launched VMs. The ivshmem mediator emulates one standard
PCI device which expose the shared memory region through its BAR2.
The shared memory region is allocated through Linux shm mechanism and
post-launched VM needs to specify the shm name and size as the acrn-dm
parameter, the VMs have same shm name parameter can communicate over
the shared memory.
For first stage, only support shared memory. Consider to support
notification(interrupt) in future.
To add a ivshmem device in device model, the usage as below
-s N,ivshmem,shm_name,shm_size
v2: Implement the ivshmem MMIO registers emulation
v3: Refine code style
Add ivshmem device usage
Refine MMIO register return value
v4: Refine comments
Use logger interfaces to print logs
Tracked-On: #4853
Signed-off-by: Yuan Liu <yuan1.liu@intel.com>
Acked-by: Yu Wang <yu1.wang@intel.com>
