The vhost-user protocol is not really Linux-specific, so let's try support QEMU's frontends and backends (including libvhost-user) in any POSIX system with this series. The main use case is to be able to use virtio devices that we don't have built-in in QEMU (e.g. virtiofsd, vhost-user-vsock, etc.) even in non-Linux systems.
The first 5 patches are more like fixes discovered at runtime on macOS or FreeBSD that could go even independently of this series. Patches 6, 7, and 8 enable building of frontends and backends (including libvhost-user) with associated code changes to succeed in compilation. The latest patch (9) adds support for the POSIX shm_open() API to create shared memory which is identified by an fd that can be shared with vhost-user backends. This is useful on those systems (like macOS) where we don't have memfd_create() or special filesystems like "/dev/shm". I put the whole series in RFC because I have some questions especially in patch 6 and 9, but in general any comment/suggestion/test are really welcome. Maybe the first 5 patches can go separately, but I only discovered those problems after testing patches 6 - 9, so I have included them in this series for now. Please let me know if you prefer that I send them separately. For now I tested this series using vhost-user-blk and QSD on macOS Sonoma 14.3.1 (aarch64), FreeBSD 14 (x86_64), and Fedora 39 (x86_64) in this way: - Start vhost-user-blk or QSD (same commands for all systems) vhost-user-blk -s /tmp/vhost.socket \ -b Fedora-Cloud-Base-39-1.5.x86_64.raw qemu-storage-daemon \ --blockdev file,filename=Fedora-Cloud-Base-39-1.5.x86_64.qcow2,node-name=file \ --blockdev qcow2,file=file,node-name=qcow2 \ --export vhost-user-blk,addr.type=unix,addr.path=/tmp/vhost.socket,id=vub,num-queues=1,node-name=qcow2,writable=on - macOS (aarch64): start QEMU (using hvf accelerator) qemu-system-aarch64 -smp 2 -cpu host -M virt,accel=hvf,memory-backend=mem \ -drive file=./build/pc-bios/edk2-aarch64-code.fd,if=pflash,format=raw,readonly=on \ -device virtio-net-device,netdev=net0 -netdev user,id=net0 \ -device ramfb -device usb-ehci -device usb-kbd \ -object memory-backend-file,mem-path="/mem0",shm=on,share=on,id=mem,size=512M \ -device vhost-user-blk-pci,num-queues=1,disable-legacy=on,chardev=char0 \ -chardev socket,id=char0,path=/tmp/vhost.socket - FreeBSD (x86_64): start QEMU (no accelerators available) qemu-system-x86_64 -smp 2 -M q35,memory-backend=mem \ -object memory-backend-file,mem-path="/mem0",shm=on,share=on,id=mem,size="512M" \ -device vhost-user-blk-pci,num-queues=1,chardev=char0 \ -chardev socket,id=char0,path=/tmp/vhost.socket - Fedora (x86_64): start QEMU (using kvm accelerator) qemu-system-x86_64 -smp 2 -M q35,accel=kvm,memory-backend=mem \ -object memory-backend-file,mem-path="/mem0",shm=on,share=on,id=mem,size="512M" \ -device vhost-user-blk-pci,num-queues=1,chardev=char0 \ -chardev socket,id=char0,path=/tmp/vhost.socket Thanks, Stefano Stefano Garzarella (9): libvhost-user: set msg.msg_control to NULL when it is empty libvhost-user: fail vu_message_write() if sendmsg() is failing libvhost-user: mask F_INFLIGHT_SHMFD if memfd is not supported vhost-user-server: don't abort if we can't set fd non-blocking contrib/vhost-user-blk: fix bind() using the right size of the address vhost-user: enable frontends on any POSIX system libvhost-user: enable it on any POSIX system contrib/vhost-user-blk: enabled it on any POSIX system hostmem-file: support POSIX shm_open() meson.build | 5 +- qapi/qom.json | 4 ++ subprojects/libvhost-user/libvhost-user.h | 2 +- backends/hostmem-file.c | 57 ++++++++++++++++- contrib/vhost-user-blk/vhost-user-blk.c | 23 +++++-- hw/net/vhost_net.c | 8 ++- subprojects/libvhost-user/libvhost-user.c | 76 ++++++++++++++++++++++- util/vhost-user-server.c | 6 +- backends/meson.build | 2 +- hw/block/Kconfig | 2 +- qemu-options.hx | 10 ++- util/meson.build | 4 +- 12 files changed, 179 insertions(+), 20 deletions(-) -- 2.43.2