[antlir2][vm] rework pre-configured VMs

Summary:
Originally I expected more sharing of various type of VMs, but after
migrating all tests, that need apparently doesn't exist. For just handful
pre-built VMs, we can provide the targets in the main defs.bzl directly. Later
more artifacts can be moved over there too.

Test Plan: CI. No real change other than renaming a target.

Reviewed By: aijayadams

Differential Revision: D50617859

fbshipit-source-id: 409525ee87961dc3ae0dfd8089ae9fb88bf8bac2

antlir/antlir2/antlir2_vm/BUCK

@@ -68,36 +68,14 @@ vm.host(
 )
 
 vm.host(
-    name = "disk-boot-5.19",
-    compatible_with = ["ovr_config//cpu:x86_64"],
-    disks = [simple_disk.get_boot_disk(
-        arch = "x86_64",
-        interface = "virtio-blk",
-        uname = "5.19",
-    )],
-)
-
-vm.host(
-    name = "default-nondisk-boot",
+    name = "default-initrd-boot",
     compatible_with = ["ovr_config//cpu:x86_64"],
     disks = [simple_disk.default_control_disk],
     initrd = initrd.default,
     kernel = metalos_kernel.default.vmlinuz,
     visibility = ["PUBLIC"],
 )
 
-vm.host(
-    name = "nondisk-boot-5.19",
-    compatible_with = ["ovr_config//cpu:x86_64"],
-    disks = [simple_disk.get_control_disk(
-        arch = "x86_64",
-        interface = "virtio-blk",
-        uname = "5.19",
-    )],
-    initrd = initrd.get("x86_64", "5.19"),
-    kernel = metalos_kernel.get("x86_64", "5.19").vmlinuz,
-)
-
 vm.host(
     name = "default-nvme-disk-boot",
     compatible_with = ["ovr_config//cpu:x86_64"],

antlir/antlir2/antlir2_vm/bzl/defs.bzl

@@ -207,4 +207,16 @@ vm = struct(
     rust_test = vm_rust_test,
     sh_test = vm_sh_test,
     run_command = vm_run_command,
+
+    # Various pre-built targets useful for building VM or writing tests
+    artifacts = struct(
+        # Pre-built VMs for `vm_host` of tests
+        default_vms = struct(
+            # initrd_boot is recommended for faster boot performance
+            initrd_boot = "//antlir/antlir2/antlir2_vm:default-initrd-boot",
+            # disk boots are recommended for more real boot sequence
+            disk_boot = "//antlir/antlir2/antlir2_vm:default-disk-boot",
+            nvme_disk_boot = "//antlir/antlir2/antlir2_vm:default-nvme-disk-boot",
+        ),
+    ),
 )

antlir/antlir2/antlir2_vm/tests/BUCK

@@ -1,5 +1,4 @@
 load("//antlir/antlir2/antlir2_vm/bzl:defs.bzl", "vm")
-load("//antlir/antlir2/antlir2_vm/bzl:preconfigured.bzl", "PRECONFIGURED_VM", "get_vm")
 load("//antlir/bzl:build_defs.bzl", "rust_binary")
 load("//metalos/vm/disks:simple.bzl", "simple_disk")
 
@@ -12,7 +11,7 @@ vm.cpp_test(
         "ENV_ARTIFACT": "$(exe :sidecar)",
     },
     run_as_bundle = True,
-    vm_host = get_vm(),
+    vm_host = vm.artifacts.default_vms.initrd_boot,
 )
 
 vm.python_test(
@@ -23,7 +22,7 @@ vm.python_test(
         "ENV_ARTIFACT": "$(exe :sidecar)",
     },
     run_as_bundle = True,
-    vm_host = get_vm(),
+    vm_host = vm.artifacts.default_vms.initrd_boot,
 )
 
 vm.rust_test(
@@ -36,7 +35,7 @@ vm.rust_test(
         "ENV_ARTIFACT": "$(exe :sidecar)",
     },
     run_as_bundle = True,
-    vm_host = get_vm(),
+    vm_host = vm.artifacts.default_vms.initrd_boot,
 )
 
 vm.sh_test(
@@ -46,7 +45,7 @@ vm.sh_test(
         "ENV_ARTIFACT": "$(exe :sidecar)",
     },
     test = "test.sh",
-    vm_host = get_vm(),
+    vm_host = vm.artifacts.default_vms.initrd_boot,
 )
 
 # Verify all pre-configured VMs
@@ -62,7 +61,11 @@ vm.sh_test(
         },
         vm_host = target,
     )
-    for name, target in PRECONFIGURED_VM.items()
+    for name, target in {
+        "disk-boot": vm.artifacts.default_vms.disk_boot,
+        "initrd-boot": vm.artifacts.default_vms.initrd_boot,
+        "nvme-disk-boot": vm.artifacts.default_vms.nvme_disk_boot,
+    }.items()
 ]
 
 # Test for sidecar
@@ -121,11 +124,11 @@ vm.rust_test(
 vm.run_command(
     name = "run-command",
     command = "uname -r",
-    vm_host = get_vm(),
+    vm_host = vm.artifacts.default_vms.initrd_boot,
 )
 
 vm.run_command(
     name = "run-command-with-location",
     command = "bash -c 'echo $(location :sidecar)'",
-    vm_host = get_vm(),
+    vm_host = vm.artifacts.default_vms.initrd_boot,
 )

antlir/antlir2/docs/docs/internals/vm-tests.md

@@ -186,7 +186,6 @@ For example, the example test target looks like this.
 
 ```
 load("//antlir/antlir2/antlir2_vm/bzl:defs.bzl", "vm")
-load("//antlir/antlir2/antlir2_vm/bzl:preconfigured.bzl", "get_vm")
 
 vm.rust_test(
     name = "rust-test",
@@ -196,7 +195,7 @@ vm.rust_test(
     env = {
         "ANTLIR2_TEST": "1",
     },
-    vm_host = get_vm(),  # vm specific
+    vm_host = vm.artifacts.default_vms.initrd_boot,  # vm specific
 )
 ```
 
@@ -209,9 +208,9 @@ optional `env` will be passed through into the VM, so your test will have access
 to them.
 
 The `vm_host` field specifies the VM host target to execute the test in.
-`get_vm()` is a function provided by `antlir2/antlir2_vm/bzl:preconfigured.bzl`
-for you to select from a list of pre-configured VMs, if you can find one that
-satisfies your need.
+`vm.artifacts.default_vms` provides several pre-configured VMs that can be
+directly used by VM test. If none of them meet your need, you would need to
+build a custom VM.
 
 ### Build a custom VM for your test (optional)