runtime-rs: add emptydir_mode to config templates

Add the emptydir_mode configuration option to all runtime-rs config
template files. CoCo configs (snp, tdx, se, coco-dev, nvidia-gpu-snp,
nvidia-gpu-tdx) default to block-encrypted via @DEFEMPTYDIRMODE_COCO@,
while non-CoCo configs (qemu, nvidia-gpu, fc) default to shared-fs
via @DEFEMPTYDIRMODE@.

Also add DEFEMPTYDIRMODE and DEFEMPTYDIRMODE_COCO variables to the
runtime-rs Makefile for template substitution.

Signed-off-by: Fabiano Fidêncio <ffidencio@nvidia.com>
Assisted-by: Cursor <cursoragent@cursor.com>

src/runtime-rs/Makefile

@@ -178,6 +178,8 @@ DEFENABLEANNOTATIONS := [\"enable_iommu\", \"virtio_fs_extra_args\", \"kernel_pa
 DEFENABLEANNOTATIONS_COCO := [\"enable_iommu\", \"virtio_fs_extra_args\", \"kernel_params\", \"kernel_verity_params\", \"default_vcpus\", \"default_memory\", \"cc_init_data\"]
 DEFDISABLEGUESTSECCOMP := true
 DEFDISABLEGUESTEMPTYDIR := false
+DEFEMPTYDIRMODE := shared-fs
+DEFEMPTYDIRMODE_COCO := block-encrypted
 ##VAR DEFAULTEXPFEATURES=[features] Default experimental features enabled
 DEFAULTEXPFEATURES := []
 DEFDISABLESELINUX := false
@@ -665,6 +667,8 @@ USER_VARS += DEFNETWORKMODEL_CLH
 USER_VARS += DEFNETWORKMODEL_QEMU
 USER_VARS += DEFNETWORKMODEL_FC
 USER_VARS += DEFDISABLEGUESTEMPTYDIR
+USER_VARS += DEFEMPTYDIRMODE
+USER_VARS += DEFEMPTYDIRMODE_COCO
 USER_VARS += DEFDISABLEGUESTSECCOMP
 USER_VARS += DEFDISABLESELINUX
 USER_VARS += DEFDISABLEGUESTSELINUX

src/runtime-rs/config/configuration-qemu-coco-dev-runtime-rs.toml.in

@@ -782,6 +782,18 @@ vfio_mode = "@DEFVFIOMODE@"
 # be created on the host and shared via virtio-fs. This is potentially slower, but allows sharing of files from host to guest.
 disable_guest_empty_dir = @DEFDISABLEGUESTEMPTYDIR@
 
+# Specifies how Kubernetes emptyDir volumes are handled.
+# Options:
+#
+#   - shared-fs (default)
+#     Shares the emptyDir folder with the guest using the method given
+#     by the `shared_fs` setting.
+#
+#   - block-encrypted
+#     Plugs a block device to be encrypted in the guest.
+#
+emptydir_mode = "@DEFEMPTYDIRMODE_COCO@"
+
 # Enabled experimental feature list, format: ["a", "b"].
 # Experimental features are features not stable enough for production,
 # they may break compatibility, and are prepared for a big version bump.

src/runtime-rs/config/configuration-qemu-nvidia-gpu-runtime-rs.toml.in

@@ -777,6 +777,18 @@ vfio_mode = "@DEFVFIOMODE_NV@"
 # be created on the host and shared via virtio-fs. This is potentially slower, but allows sharing of files from host to guest.
 disable_guest_empty_dir = @DEFDISABLEGUESTEMPTYDIR@
 
+# Specifies how Kubernetes emptyDir volumes are handled.
+# Options:
+#
+#   - shared-fs (default)
+#     Shares the emptyDir folder with the guest using the method given
+#     by the `shared_fs` setting.
+#
+#   - block-encrypted
+#     Plugs a block device to be encrypted in the guest.
+#
+emptydir_mode = "@DEFEMPTYDIRMODE@"
+
 # Enabled experimental feature list, format: ["a", "b"].
 # Experimental features are features not stable enough for production,
 # they may break compatibility, and are prepared for a big version bump.

src/runtime-rs/config/configuration-qemu-nvidia-gpu-snp-runtime-rs.toml.in

@@ -709,6 +709,18 @@ vfio_mode = "@DEFVFIOMODE_NV@"
 # be created on the host and shared via virtio-fs. This is potentially slower, but allows sharing of files from host to guest.
 disable_guest_empty_dir = @DEFDISABLEGUESTEMPTYDIR@
 
+# Specifies how Kubernetes emptyDir volumes are handled.
+# Options:
+#
+#   - shared-fs (default)
+#     Shares the emptyDir folder with the guest using the method given
+#     by the `shared_fs` setting.
+#
+#   - block-encrypted
+#     Plugs a block device to be encrypted in the guest.
+#
+emptydir_mode = "@DEFEMPTYDIRMODE_COCO@"
+
 # Enabled experimental feature list, format: ["a", "b"].
 # Experimental features are features not stable enough for production,
 # they may break compatibility, and are prepared for a big version bump.

src/runtime-rs/config/configuration-qemu-nvidia-gpu-tdx-runtime-rs.toml.in

@@ -685,6 +685,18 @@ vfio_mode = "@DEFVFIOMODE_NV@"
 # be created on the host and shared via virtio-fs. This is potentially slower, but allows sharing of files from host to guest.
 disable_guest_empty_dir = @DEFDISABLEGUESTEMPTYDIR@
 
+# Specifies how Kubernetes emptyDir volumes are handled.
+# Options:
+#
+#   - shared-fs (default)
+#     Shares the emptyDir folder with the guest using the method given
+#     by the `shared_fs` setting.
+#
+#   - block-encrypted
+#     Plugs a block device to be encrypted in the guest.
+#
+emptydir_mode = "@DEFEMPTYDIRMODE_COCO@"
+
 # Enabled experimental feature list, format: ["a", "b"].
 # Experimental features are features not stable enough for production,
 # they may break compatibility, and are prepared for a big version bump.

src/runtime-rs/config/configuration-qemu-runtime-rs.toml.in

@@ -779,6 +779,18 @@ vfio_mode = "@DEFVFIOMODE@"
 # be created on the host and shared via virtio-fs. This is potentially slower, but allows sharing of files from host to guest.
 disable_guest_empty_dir = @DEFDISABLEGUESTEMPTYDIR@
 
+# Specifies how Kubernetes emptyDir volumes are handled.
+# Options:
+#
+#   - shared-fs (default)
+#     Shares the emptyDir folder with the guest using the method given
+#     by the `shared_fs` setting.
+#
+#   - block-encrypted
+#     Plugs a block device to be encrypted in the guest.
+#
+emptydir_mode = "@DEFEMPTYDIRMODE@"
+
 # Enabled experimental feature list, format: ["a", "b"].
 # Experimental features are features not stable enough for production,
 # they may break compatibility, and are prepared for a big version bump.

src/runtime-rs/config/configuration-qemu-se-runtime-rs.toml.in

@@ -662,6 +662,18 @@ vfio_mode = "@DEFVFIOMODE_SE@"
 # be created on the host and shared via virtio-fs. This is potentially slower, but allows sharing of files from host to guest.
 disable_guest_empty_dir = @DEFDISABLEGUESTEMPTYDIR@
 
+# Specifies how Kubernetes emptyDir volumes are handled.
+# Options:
+#
+#   - shared-fs (default)
+#     Shares the emptyDir folder with the guest using the method given
+#     by the `shared_fs` setting.
+#
+#   - block-encrypted
+#     Plugs a block device to be encrypted in the guest.
+#
+emptydir_mode = "@DEFEMPTYDIRMODE_COCO@"
+
 # Enabled experimental feature list, format: ["a", "b"].
 # Experimental features are features not stable enough for production,
 # they may break compatibility, and are prepared for a big version bump.

src/runtime-rs/config/configuration-qemu-snp-runtime-rs.toml.in

@@ -704,6 +704,18 @@ vfio_mode = "@DEFVFIOMODE@"
 # be created on the host and shared via virtio-fs. This is potentially slower, but allows sharing of files from host to guest.
 disable_guest_empty_dir = @DEFDISABLEGUESTEMPTYDIR@
 
+# Specifies how Kubernetes emptyDir volumes are handled.
+# Options:
+#
+#   - shared-fs (default)
+#     Shares the emptyDir folder with the guest using the method given
+#     by the `shared_fs` setting.
+#
+#   - block-encrypted
+#     Plugs a block device to be encrypted in the guest.
+#
+emptydir_mode = "@DEFEMPTYDIRMODE_COCO@"
+
 # Enabled experimental feature list, format: ["a", "b"].
 # Experimental features are features not stable enough for production,
 # they may break compatibility, and are prepared for a big version bump.

src/runtime-rs/config/configuration-qemu-tdx-runtime-rs.toml.in

@@ -680,6 +680,18 @@ vfio_mode = "@DEFVFIOMODE@"
 # be created on the host and shared via virtio-fs. This is potentially slower, but allows sharing of files from host to guest.
 disable_guest_empty_dir = @DEFDISABLEGUESTEMPTYDIR@
 
+# Specifies how Kubernetes emptyDir volumes are handled.
+# Options:
+#
+#   - shared-fs (default)
+#     Shares the emptyDir folder with the guest using the method given
+#     by the `shared_fs` setting.
+#
+#   - block-encrypted
+#     Plugs a block device to be encrypted in the guest.
+#
+emptydir_mode = "@DEFEMPTYDIRMODE_COCO@"
+
 # Enabled experimental feature list, format: ["a", "b"].
 # Experimental features are features not stable enough for production,
 # they may break compatibility, and are prepared for a big version bump.

src/runtime-rs/config/configuration-rs-fc.toml.in

@@ -411,6 +411,18 @@ static_sandbox_resource_mgmt = @DEFSTATICRESOURCEMGMT_FC@
 # be created on the host and shared via virtio-fs. This is potentially slower, but allows sharing of files from host to guest.
 disable_guest_empty_dir = @DEFDISABLEGUESTEMPTYDIR@
 
+# Specifies how Kubernetes emptyDir volumes are handled.
+# Options:
+#
+#   - shared-fs (default)
+#     Shares the emptyDir folder with the guest using the method given
+#     by the `shared_fs` setting.
+#
+#   - block-encrypted
+#     Plugs a block device to be encrypted in the guest.
+#
+emptydir_mode = "@DEFEMPTYDIRMODE@"
+
 # Enabled experimental feature list, format: ["a", "b"].
 # Experimental features are features not stable enough for production,
 # they may break compatibility, and are prepared for a big version bump.