This is the first step to being able to do thingsn like having a static base image for an application VM, and another image containing the application to run. When we actually use multiple images we'll need to change how we boot so we know the kernel is booting from the right image — probably by PARTUUID or PARTLABEL — because we can't guarantee how the kernel orders disks inside the VM. Signed-off-by: Alyssa Ross <hi@alyssa.is> --- Documentation/creating-vms.adoc | 8 ++++--- host/start-vm/start-vm.rs | 41 +++++++++++++++++++++++++++------ vm/app/catgirl/Makefile | 12 +++++----- vm/app/lynx/Makefile | 12 +++++----- vm/sys/net/Makefile | 12 +++++----- 5 files changed, 57 insertions(+), 28 deletions(-) diff --git a/Documentation/creating-vms.adoc b/Documentation/creating-vms.adoc index d967098..6d4fde0 100644 --- a/Documentation/creating-vms.adoc +++ b/Documentation/creating-vms.adoc @@ -15,8 +15,9 @@ The directory can contain the following files: vmlinux:: An uncompressed Linux kernel image for the VM to boot. *Required.* -rootfs.ext4:: A disk image that will be provided to the guest as a -virtio-blk device. *Required.* +blk:: A directory containing disk images (with file names ending in +".img") that will be provided to the guest as a virtio-blk device. +Order is not guaranteed. At least one image is *required*. providers/net:: A directory containing a file named for each VM that should provide networking to this VM. The contents of these files are @@ -33,7 +34,8 @@ appvm-lynx ├── providers/ │ └── net/ │ └── netvm -├── rootfs.ext4 +├── blk/ +│ └── root.img └── vmlinux* ---- diff --git a/host/start-vm/start-vm.rs b/host/start-vm/start-vm.rs index 11715f1..96d7eb1 100644 --- a/host/start-vm/start-vm.rs +++ b/host/start-vm/start-vm.rs @@ -5,7 +5,7 @@ mod ch; mod net; use std::env::{args, current_dir}; -use std::ffi::{CString, OsString}; +use std::ffi::{CString, OsStr, OsString}; use std::io::{self, ErrorKind}; use std::os::unix::prelude::*; use std::path::PathBuf; @@ -76,12 +76,39 @@ fn vm_command(dir: PathBuf) -> Result<Command, String> { kernel }); - command.arg("--disk").arg({ - let mut disk = OsString::from("path=/ext/svc/data/"); - disk.push(&vm_name); - disk.push("/rootfs.ext4,readonly=on"); - disk - }); + command.arg("--disk"); + + let mut blk_dir = PathBuf::new(); + blk_dir.push("/ext/svc/data"); + blk_dir.push(vm_name); + blk_dir.push("blk"); + match blk_dir.read_dir() { + Ok(entries) => { + for result in entries { + let entry = result + .map_err(|e| format!("examining directory entry: {}", e))? + .path(); + + if entry.extension() != Some(OsStr::new("img")) { + continue; + } + + if entry.as_os_str().as_bytes().contains(&b',') { + return Err(format!("illegal ',' character in path {:?}", entry)); + } + + let mut arg = OsString::from("path="); + arg.push(entry); + arg.push(",readonly=on"); + command.arg(arg); + } + } + Err(e) => return Err(format!("reading directory {:?}: {}", blk_dir, e)), + } + + if command.get_args().last() == Some(OsStr::new("--disk")) { + return Err("no block devices specified".to_string()); + } command.arg("--serial").arg({ let mut serial = OsString::from("file=/run/"); diff --git a/vm/app/catgirl/Makefile b/vm/app/catgirl/Makefile index a32826b..9016745 100644 --- a/vm/app/catgirl/Makefile +++ b/vm/app/catgirl/Makefile @@ -12,7 +12,7 @@ VMM = qemu HOST_FILES = host/data/appvm-catgirl/providers/net/netvm HOST_BUILD_FILES = \ - build/host/data/appvm-catgirl/rootfs.ext4 \ + build/host/data/appvm-catgirl/blk/root.img \ build/host/data/appvm-catgirl/vmlinux # We produce a directory, but that doesn't play nice with Make, @@ -35,7 +35,7 @@ build/host/data/appvm-catgirl/vmlinux: $(VMLINUX) # tar2ext4 will leave half a filesystem behind if it's interrupted # half way through. -build/host/data/appvm-catgirl/rootfs.ext4: build/rootfs.tar +build/host/data/appvm-catgirl/blk/root.img: build/rootfs.tar mkdir -p $$(dirname $@) tar2ext4 -i build/rootfs.tar -o $@.tmp mv $@.tmp $@ @@ -92,9 +92,9 @@ build/etc/s6-rc: $(VM_S6_RC_FILES) s6-rc-compile $@ $$dir; \ exit=$$?; rm -r $$dir; exit $$exit -run-qemu: build/host/data/appvm-catgirl/rootfs.ext4 +run-qemu: build/host/data/appvm-catgirl/blk/root.img $(QEMU_KVM) -m 128 -cpu host -machine q35,kernel=$(KERNEL) -vga none \ - -drive file=build/host/data/appvm-catgirl/rootfs.ext4,if=virtio,format=raw,readonly=on \ + -drive file=build/host/data/appvm-catgirl/blk/root.img,if=virtio,format=raw,readonly=on \ -append "console=ttyS0 root=/dev/vda" \ -netdev user,id=net0 \ -device virtio-net,netdev=net0,mac=0A:B3:EC:00:00:00 \ @@ -103,11 +103,11 @@ run-qemu: build/host/data/appvm-catgirl/rootfs.ext4 -device virtconsole,chardev=virtiocon0 .PHONY: run-qemu -run-cloud-hypervisor: build/host/data/appvm-catgirl/rootfs.ext4 +run-cloud-hypervisor: build/host/data/appvm-catgirl/blk/root.img $(CLOUD_HYPERVISOR) \ --api-socket path=vmm.sock \ --memory size=128M \ - --disk path=build/host/data/appvm-catgirl/rootfs.ext4,readonly=on \ + --disk path=build/host/data/appvm-catgirl/blk/root.img,readonly=on \ --net tap=tap0,mac=0A:B3:EC:00:00:00 \ --kernel $(KERNEL) \ --cmdline "console=ttyS0 root=/dev/vda" \ diff --git a/vm/app/lynx/Makefile b/vm/app/lynx/Makefile index c25c9ab..ff87cb8 100644 --- a/vm/app/lynx/Makefile +++ b/vm/app/lynx/Makefile @@ -12,7 +12,7 @@ VMM = qemu HOST_FILES = host/data/appvm-lynx/providers/net/netvm HOST_BUILD_FILES = \ - build/host/data/appvm-lynx/rootfs.ext4 \ + build/host/data/appvm-lynx/blk/root.img \ build/host/data/appvm-lynx/vmlinux # We produce a directory, but that doesn't play nice with Make, @@ -35,7 +35,7 @@ build/host/data/appvm-lynx/vmlinux: $(VMLINUX) # tar2ext4 will leave half a filesystem behind if it's interrupted # half way through. -build/host/data/appvm-lynx/rootfs.ext4: build/rootfs.tar +build/host/data/appvm-lynx/blk/root.img: build/rootfs.tar mkdir -p $$(dirname $@) tar2ext4 -i build/rootfs.tar -o $@.tmp mv $@.tmp $@ @@ -91,9 +91,9 @@ build/etc/s6-rc: $(VM_S6_RC_FILES) s6-rc-compile $@ $$dir; \ exit=$$?; rm -r $$dir; exit $$exit -run-qemu: build/host/data/appvm-lynx/rootfs.ext4 +run-qemu: build/host/data/appvm-lynx/blk/root.img $(QEMU_KVM) -m 128 -cpu host -machine q35,kernel=$(KERNEL) -vga none \ - -drive file=build/host/data/appvm-lynx/rootfs.ext4,if=virtio,format=raw,readonly=on \ + -drive file=build/host/data/appvm-lynx/blk/root.img,if=virtio,format=raw,readonly=on \ -append "console=ttyS0 root=/dev/vda" \ -netdev user,id=net0 \ -device virtio-net,netdev=net0,mac=0A:B3:EC:00:00:00 \ @@ -102,11 +102,11 @@ run-qemu: build/host/data/appvm-lynx/rootfs.ext4 -device virtconsole,chardev=virtiocon0 .PHONY: run-qemu -run-cloud-hypervisor: build/host/data/appvm-lynx/rootfs.ext4 +run-cloud-hypervisor: build/host/data/appvm-lynx/blk/root.img $(CLOUD_HYPERVISOR) \ --api-socket path=vmm.sock \ --memory size=128M \ - --disk path=build/host/data/appvm-lynx/rootfs.ext4,readonly=on \ + --disk path=build/host/data/appvm-lynx/blk/root.img,readonly=on \ --net tap=tap0,mac=0A:B3:EC:00:00:00 \ --kernel $(KERNEL) \ --cmdline "console=ttyS0 root=/dev/vda" \ diff --git a/vm/sys/net/Makefile b/vm/sys/net/Makefile index 7cb7a5f..0b5fe8f 100644 --- a/vm/sys/net/Makefile +++ b/vm/sys/net/Makefile @@ -10,7 +10,7 @@ CLOUD_HYPERVISOR = cloud-hypervisor VMM = qemu HOST_BUILD_FILES = \ - build/host/data/netvm/rootfs.ext4 \ + build/host/data/netvm/blk/root.img \ build/host/data/netvm/vmlinux # We produce a directory, but that doesn't play nice with Make, @@ -32,7 +32,7 @@ build/host/data/netvm/vmlinux: $(VMLINUX) # tar2ext4 will leave half a filesystem behind if it's interrupted # half way through. -build/host/data/netvm/rootfs.ext4: build/rootfs.tar +build/host/data/netvm/blk/root.img: build/rootfs.tar mkdir -p $$(dirname $@) tar2ext4 -i build/rootfs.tar -o $@.tmp mv $@.tmp $@ @@ -97,9 +97,9 @@ build/etc/s6-rc: $(VM_S6_RC_FILES) s6-rc-compile $@ $$dir; \ exit=$$?; rm -r $$dir; exit $$exit -run-qemu: build/host/data/netvm/rootfs.ext4 +run-qemu: build/host/data/netvm/blk/root.img $(QEMU_KVM) -m 128 -cpu host -machine q35,kernel=$(KERNEL) -vga none \ - -drive file=build/host/data/netvm/rootfs.ext4,if=virtio,format=raw,readonly=on \ + -drive file=build/host/data/netvm/blk/root.img,if=virtio,format=raw,readonly=on \ -append "console=ttyS0 root=/dev/vda" \ -netdev user,id=net0 \ -device e1000e,netdev=net0 \ @@ -110,11 +110,11 @@ run-qemu: build/host/data/netvm/rootfs.ext4 -device virtconsole,chardev=virtiocon0 .PHONY: run-qemu -run-cloud-hypervisor: build/host/data/netvm/rootfs.ext4 +run-cloud-hypervisor: build/host/data/netvm/blk/root.img $(CLOUD_HYPERVISOR) \ --api-socket path=vmm.sock \ --memory size=128M \ - --disk path=build/host/data/netvm/rootfs.ext4,readonly=on \ + --disk path=build/host/data/netvm/blk/root.img,readonly=on \ --net tap=tap0 tap=tap1,mac=0A:B3:EC:80:00:00 \ --kernel $(KERNEL) \ --cmdline "console=ttyS0 root=/dev/vda" \ -- 2.37.1