[PATCH 1/2] img/app: change virtio-fs tag to "host"

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* [PATCH 1/2] img/app: change virtio-fs tag to "host"
@ 2025-12-12 21:54 Alyssa Ross
  2025-12-12 21:54 ` [PATCH 2/2] img/app: move virtio-fs mountpoint to /host Alyssa Ross
  0 siblings, 1 reply; 2+ messages in thread
From: Alyssa Ross @ 2025-12-12 21:54 UTC (permalink / raw)
  To: devel

It doesn't seem likely to me that we'll have multiple virtio-fs
devices from the host, so let's use something a bit more clear and
precise.

Signed-off-by: Alyssa Ross <hi@alyssa.is>
---
 Documentation/using-spectrum/creating-custom-vms.adoc | 2 +-
 img/app/Makefile                                      | 4 ++--
 img/app/image/etc/mdev/virtiofs                       | 2 +-
 img/app/scripts/start-virtiofsd.elb                   | 2 +-
 release/checks/wayland/default.nix                    | 4 ++--
 tools/start-vmm/lib.rs                                | 2 +-
 tools/start-vmm/tests/vm_command-basic.rs             | 2 +-
 7 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/Documentation/using-spectrum/creating-custom-vms.adoc b/Documentation/using-spectrum/creating-custom-vms.adoc
index a397ac50..8d915e1a 100644
--- a/Documentation/using-spectrum/creating-custom-vms.adoc
+++ b/Documentation/using-spectrum/creating-custom-vms.adoc
@@ -91,7 +91,7 @@ should configure `eth0` with the IPv4 address `100.64.165.70` (because
 === Filesystem
 
 Every VM has a virtio-fs device that exposes the /run/vm/by-id/_VM
-ID_/fs directory on the host, with the tag "virtiofs0".  The VM cannot
+ID_/fs directory on the host, with the tag "host".  The VM cannot
 write directly into that directory, but it's possible to create a
 subdirectory on the host and bind mount a directory from a writeable
 filesystem into it to provide the VM with access to shared storage.
diff --git a/img/app/Makefile b/img/app/Makefile
index 7354f892..69c85bba 100644
--- a/img/app/Makefile
+++ b/img/app/Makefile
@@ -99,7 +99,7 @@ run-qemu: $(imgdir)/appvm/blk/root.img start-vhost-user-net start-virtiofsd
 	    -netdev vhost-user,id=net0,chardev=vhost-user-net \
 	    -device virtio-net,netdev=net0,mac=02:00:00:00:00:01 \
 	    -chardev socket,id=virtiofsd,path=build/virtiofsd.sock \
-	    -device vhost-user-fs-pci,chardev=virtiofsd,tag=virtiofs0 \
+	    -device vhost-user-fs-pci,chardev=virtiofsd,tag=host \
 	    -device virtio-gpu-rutabaga-pci,cross-domain=on,hostmem=8G \
 	    -audio driver=pipewire,model=virtio \
 	    -object memory-backend-memfd,id=mem,size=256M,share=on \
@@ -117,7 +117,7 @@ run-cloud-hypervisor: $(imgdir)/appvm/blk/root.img start-vhost-user-gpu start-vh
 	    --api-socket path=build/vmm.sock \
 	    --memory size=1G,shared=on \
 	    --disk path=$(imgdir)/appvm/blk/root.img,readonly=on \
-	    --fs tag=virtiofs0,socket=build/virtiofsd.sock \
+	    --fs tag=host,socket=build/virtiofsd.sock \
 	    --gpu socket=build/vhost-user-gpu.sock \
 	    --vsock cid=3,socket=build/vsock.sock \
 	    --net mac=02:00:00:00:00:01,vhost_user=on,socket=build/vhost-user-net.sock \
diff --git a/img/app/image/etc/mdev/virtiofs b/img/app/image/etc/mdev/virtiofs
index b6e505bc..bda77483 100755
--- a/img/app/image/etc/mdev/virtiofs
+++ b/img/app/image/etc/mdev/virtiofs
@@ -7,6 +7,6 @@ background {
   # virtiofs filesystems, so we only supported a single, hardcoded
   # filesystem tag for now.
   if { mkdir -p /run/virtiofs/virtiofs0 }
-  if { mount -t virtiofs -o nodev virtiofs0 /run/virtiofs/virtiofs0 }
+  if { mount -t virtiofs -o nodev host /run/virtiofs/virtiofs0 }
   /etc/mdev/listen virtiofs0
 }
diff --git a/img/app/scripts/start-virtiofsd.elb b/img/app/scripts/start-virtiofsd.elb
index fa3a234e..9efb436b 100755
--- a/img/app/scripts/start-virtiofsd.elb
+++ b/img/app/scripts/start-virtiofsd.elb
@@ -11,5 +11,5 @@ background {
   if { importas -Si CONFIG mount --rbind -- ${CONFIG}/fs build/fs/config }
   unshare --map-user 1000 --map-group 1000
   importas -SsD virtiofsd VIRTIOFSD
-  $VIRTIOFSD --fd 0 --shared-dir build/fs --tag virtiofs0
+  $VIRTIOFSD --fd 0 --shared-dir build/fs --tag host
 }
diff --git a/release/checks/wayland/default.nix b/release/checks/wayland/default.nix
index a053e605..55c7d6d1 100644
--- a/release/checks/wayland/default.nix
+++ b/release/checks/wayland/default.nix
@@ -32,7 +32,7 @@ testers.nixosTest ({ lib, pkgs, ... }: {
     systemd.services.cloud-hypervisor = {
       after = [ "crosvm-gpu.service" "weston.service" ];
       requires = [ "crosvm-gpu.service" "weston.service" ];
-      serviceConfig.ExecStart = "${lib.getExe pkgs.cloud-hypervisor} --memory shared=on --disk path=${appvm}/lib/spectrum/img/appvm/blk/root.img,readonly=on --cmdline \"console=ttyS0 root=PARTLABEL=root\" --fs socket=/run/virtiofsd.sock,tag=virtiofs0 --gpu socket=/run/crosvm-gpu.sock --vsock cid=3,socket=/run/vsock.sock --serial tty --console null --kernel ${appvm}/lib/spectrum/img/appvm/vmlinux";
+      serviceConfig.ExecStart = "${lib.getExe pkgs.cloud-hypervisor} --memory shared=on --disk path=${appvm}/lib/spectrum/img/appvm/blk/root.img,readonly=on --cmdline \"console=ttyS0 root=PARTLABEL=root\" --fs socket=/run/virtiofsd.sock,tag=host --gpu socket=/run/crosvm-gpu.sock --vsock cid=3,socket=/run/vsock.sock --serial tty --console null --kernel ${appvm}/lib/spectrum/img/appvm/vmlinux";
     };
 
     systemd.services.crosvm = {
@@ -79,7 +79,7 @@ testers.nixosTest ({ lib, pkgs, ... }: {
     };
 
     systemd.services.virtiofsd = {
-      serviceConfig.ExecStart = "${lib.getExe pkgs.virtiofsd} --fd 3 --shared-dir /shared --tag virtiofs0";
+      serviceConfig.ExecStart = "${lib.getExe pkgs.virtiofsd} --fd 3 --shared-dir /shared --tag host";
       serviceConfig.Restart = "on-success";
       requires = [ "shared-config.mount" ];
       after = [ "shared-config.mount" ];
diff --git a/tools/start-vmm/lib.rs b/tools/start-vmm/lib.rs
index b44e0375..4b2aedda 100644
--- a/tools/start-vmm/lib.rs
+++ b/tools/start-vmm/lib.rs
@@ -81,7 +81,7 @@ pub fn vm_config(vm_dir: &Path) -> Result<VmConfig, String> {
             Err(e) => return Err(format!("reading directory {blk_dir:?}: {e}")),
         },
         fs: [FsConfig {
-            tag: "virtiofs0",
+            tag: "host",
             socket: format!(
                 "/run/service/vm-services/instance/{vm_name}/data/service/vhost-user-fs/env/virtiofsd.sock"
             ),
diff --git a/tools/start-vmm/tests/vm_command-basic.rs b/tools/start-vmm/tests/vm_command-basic.rs
index 866a6e19..533e2d2d 100644
--- a/tools/start-vmm/tests/vm_command-basic.rs
+++ b/tools/start-vmm/tests/vm_command-basic.rs
@@ -28,7 +28,7 @@ fn main() -> std::io::Result<()> {
     assert!(disk1.readonly);
     assert_eq!(config.fs.len(), 1);
     let fs1 = &config.fs[0];
-    assert_eq!(fs1.tag, "virtiofs0");
+    assert_eq!(fs1.tag, "host");
     let expected =
         "/run/service/vm-services/instance/testvm/data/service/vhost-user-fs/env/virtiofsd.sock";
     assert_eq!(fs1.socket, expected);

base-commit: 814a589b2b0fb4eeed06e1a1a9ce536f6b5ee91d
-- 
2.51.0


^ permalink raw reply related	[flat|nested] 2+ messages in thread

* [PATCH 2/2] img/app: move virtio-fs mountpoint to /host
  2025-12-12 21:54 [PATCH 1/2] img/app: change virtio-fs tag to "host" Alyssa Ross
@ 2025-12-12 21:54 ` Alyssa Ross
  0 siblings, 0 replies; 2+ messages in thread
From: Alyssa Ross @ 2025-12-12 21:54 UTC (permalink / raw)
  To: devel

It doesn't really make sense for this to be under /run, and
"virtiofs0" is not a very descriptive name, especially now that it's
no longer used on the host side.

Signed-off-by: Alyssa Ross <hi@alyssa.is>
---
 Documentation/using-spectrum/vm-file-access.adoc |  8 ++++----
 .../image/etc/vm-sysupdate.d/50-verity.transfer  |  2 +-
 .../image/etc/vm-sysupdate.d/60-root.transfer    |  2 +-
 .../image/etc/vm-sysupdate.d/70-kernel.transfer  |  2 +-
 img/app/Makefile                                 |  2 +-
 .../image/etc/flatpak/installations.d/extra.conf |  2 +-
 img/app/image/etc/mdev/virtiofs                  |  8 ++------
 img/app/image/etc/s6-rc/app/run                  | 16 ++++++++--------
 tools/default.nix                                |  2 +-
 vm/app/systemd-sysupdate/download-update         |  6 +++---
 10 files changed, 23 insertions(+), 27 deletions(-)

diff --git a/Documentation/using-spectrum/vm-file-access.adoc b/Documentation/using-spectrum/vm-file-access.adoc
index 1b4fe9a5..a76272f1 100644
--- a/Documentation/using-spectrum/vm-file-access.adoc
+++ b/Documentation/using-spectrum/vm-file-access.adoc
@@ -37,10 +37,10 @@ the portal.
 When using an application that doesn't implement the File Chooser API,
 you can still give it access to files manually.  Each VM has
 xref:creating-custom-vms.adoc#filesystem[access] to the
-/run/vm/by-id/_VM ID_/fs directory on the host (mounted at
-/run/virtiofs/virtiofs0 in the default Spectrum VM image).  For the
-VM, this directory is read-only, but writeable files and directories
-can be bind-mounted into it:
+/run/vm/by-id/_VM ID_/fs directory on the host (mounted at /host in
+the default Spectrum VM image).  For the VM, this directory is
+read-only, but writeable files and directories can be bind-mounted
+into it:
 
 [example]
 ====
diff --git a/host/rootfs/image/etc/vm-sysupdate.d/50-verity.transfer b/host/rootfs/image/etc/vm-sysupdate.d/50-verity.transfer
index ab4997c8..8c764fbd 100644
--- a/host/rootfs/image/etc/vm-sysupdate.d/50-verity.transfer
+++ b/host/rootfs/image/etc/vm-sysupdate.d/50-verity.transfer
@@ -13,6 +13,6 @@ MatchPattern=Spectrum_@v_@u.verity
 
 [Target]
 Type=regular-file
-Path=/run/virtiofs/virtiofs0/updates
+Path=/host/updates
 MatchPattern=Spectrum_@v_@u.verity
 Mode=0644
diff --git a/host/rootfs/image/etc/vm-sysupdate.d/60-root.transfer b/host/rootfs/image/etc/vm-sysupdate.d/60-root.transfer
index 8a317568..93af34ac 100644
--- a/host/rootfs/image/etc/vm-sysupdate.d/60-root.transfer
+++ b/host/rootfs/image/etc/vm-sysupdate.d/60-root.transfer
@@ -13,6 +13,6 @@ MatchPattern=Spectrum_@v_@u.root
 
 [Target]
 Type=regular-file
-Path=/run/virtiofs/virtiofs0/updates
+Path=/host/updates
 MatchPattern=Spectrum_@v_@u.root
 Mode=0644
diff --git a/host/rootfs/image/etc/vm-sysupdate.d/70-kernel.transfer b/host/rootfs/image/etc/vm-sysupdate.d/70-kernel.transfer
index cb181239..90d26874 100644
--- a/host/rootfs/image/etc/vm-sysupdate.d/70-kernel.transfer
+++ b/host/rootfs/image/etc/vm-sysupdate.d/70-kernel.transfer
@@ -13,6 +13,6 @@ MatchPattern=Spectrum_@v.efi
 
 [Target]
 Type=regular-file
-Path=/run/virtiofs/virtiofs0/updates
+Path=/host/updates
 MatchPattern=Spectrum_@v.efi
 Mode=0644
diff --git a/img/app/Makefile b/img/app/Makefile
index 69c85bba..7e3d05b2 100644
--- a/img/app/Makefile
+++ b/img/app/Makefile
@@ -30,7 +30,7 @@ $(imgdir)/appvm/blk/root.img: ../../scripts/make-gpt.sh ../../scripts/sfdisk-fie
 	    build/rootfs.erofs:root:5460386f-2203-4911-8694-91400125c604:root
 	mv $@.tmp $@
 
-DIRS = dev home/user run mnt proc sys tmp \
+DIRS = dev home/user host run mnt proc sys tmp \
 	etc/s6-linux-init/run-image/pipewire \
 	etc/s6-linux-init/run-image/service \
 	etc/s6-linux-init/run-image/user \
diff --git a/img/app/image/etc/flatpak/installations.d/extra.conf b/img/app/image/etc/flatpak/installations.d/extra.conf
index 448902b4..4b3bd5e6 100644
--- a/img/app/image/etc/flatpak/installations.d/extra.conf
+++ b/img/app/image/etc/flatpak/installations.d/extra.conf
@@ -2,4 +2,4 @@
 # SPDX-FileCopyrightText: 2025 Alyssa Ross <hi@alyssa.is>
 
 [Installation "virtiofs"]
-Path=/run/virtiofs/virtiofs0/config/flatpak
+Path=/host/config/flatpak
diff --git a/img/app/image/etc/mdev/virtiofs b/img/app/image/etc/mdev/virtiofs
index bda77483..a0b9dd7d 100755
--- a/img/app/image/etc/mdev/virtiofs
+++ b/img/app/image/etc/mdev/virtiofs
@@ -3,10 +3,6 @@
 # SPDX-FileCopyrightText: 2022-2023 Alyssa Ross <hi@alyssa.is>
 
 background {
-  # There's currently no kernel mechanism to let us enumerate available
-  # virtiofs filesystems, so we only supported a single, hardcoded
-  # filesystem tag for now.
-  if { mkdir -p /run/virtiofs/virtiofs0 }
-  if { mount -t virtiofs -o nodev host /run/virtiofs/virtiofs0 }
-  /etc/mdev/listen virtiofs0
+  if { mount -t virtiofs -o nodev host /host }
+  /etc/mdev/listen virtiofs-host
 }
diff --git a/img/app/image/etc/s6-rc/app/run b/img/app/image/etc/s6-rc/app/run
index 997897de..f91877d4 100755
--- a/img/app/image/etc/s6-rc/app/run
+++ b/img/app/image/etc/s6-rc/app/run
@@ -7,27 +7,27 @@ export TMPDIR /run
 export HOME /home/user
 cd /home/user
 
-if { /etc/mdev/wait virtiofs0 }
+if { /etc/mdev/wait virtiofs-host }
 
 foreground {
-  redirfd -r 0 /run/virtiofs/virtiofs0/config/type
+  redirfd -r 0 /host/config/type
   withstdinas -E type
   case $type {
     appimage {
       if { modprobe loop }
       if {
-        backtick -E offset { /run/virtiofs/virtiofs0/config/run --appimage-offset }
-        mount -o offset=${offset},nodev /run/virtiofs/virtiofs0/config/run /mnt
+        backtick -E offset { /host/config/run --appimage-offset }
+        mount -o offset=${offset},nodev /host/config/run /mnt
       }
       s6-setuidgid user
-      export APPIMAGE /run/virtiofs/virtiofs0/config/run
+      export APPIMAGE /host/config/run
       export APPDIR /mnt
       export ARGV0 /mnt/AppRun
       export LD_LIBRARY_PATH /lib64
       /mnt/AppRun
     }
     flatpak {
-      s6-envdir -fnL /run/virtiofs/virtiofs0/config/params
+      s6-envdir -fnL /host/config/params
       s6-setuidgid user
       multisubstitute {
         importas -iu id id
@@ -42,12 +42,12 @@ foreground {
     nix {
       if {
 	mount -t overlay
-	  -o ro,nosuid,nodev,lowerdir=/nix/store:/run/virtiofs/virtiofs0/config/nix/store
+	  -o ro,nosuid,nodev,lowerdir=/nix/store:/host/config/nix/store
 	  store /nix/store
       }
 
       s6-setuidgid user
-      /run/virtiofs/virtiofs0/config/run
+      /host/config/run
     }
   }
   fdmove -c 1 2
diff --git a/tools/default.nix b/tools/default.nix
index da82f075..56f41cd9 100644
--- a/tools/default.nix
+++ b/tools/default.nix
@@ -101,7 +101,7 @@ stdenv.mkDerivation (finalAttrs: {
     (lib.mesonBool "app" appSupport)
     (lib.mesonBool "host" hostSupport)
     (lib.mesonBool "driver" driverSupport)
-    "-Dhostfsrootdir=/run/virtiofs/virtiofs0"
+    "-Dhostfsrootdir=/host"
     "-Dtests=false"
     "-Dunwind=false"
     "-Dwerror=true"
diff --git a/vm/app/systemd-sysupdate/download-update b/vm/app/systemd-sysupdate/download-update
index 40fde88d..b76c9deb 100755
--- a/vm/app/systemd-sysupdate/download-update
+++ b/vm/app/systemd-sysupdate/download-update
@@ -5,7 +5,7 @@
 export LC_ALL C
 export LANGUAGE C
 unshare -mr
-if { mount -toverlay -o nosuid,nodev,noexec,nosymfollow,lowerdir=/run/virtiofs/virtiofs0/etc:/etc -- overlay /etc }
+if { mount -toverlay -o nosuid,nodev,noexec,nosymfollow,lowerdir=/host/etc:/etc -- overlay /etc }
 backtick tmpdir { mktemp -d /tmp/sysupdate-XXXXXX }
 # Not a useless use of cat: if there are NUL bytes in the URL
 # busybox's awk might misbehave.
@@ -70,6 +70,6 @@ if {
 # they cause globbing in the curl command-line tool by default.  Use --globoff
 # to disable this feature.
 if { $CURL_PATH -L --proto-redir =http,https --globoff
-     -o /run/virtiofs/virtiofs0/updates/SHA256SUMS -- ${update_url}/SHA256SUMS }
+     -o /host/updates/SHA256SUMS -- ${update_url}/SHA256SUMS }
 $CURL_PATH -L --proto-redir =http,https --globoff
-     -o /run/virtiofs/virtiofs0/updates/SHA256SUMS.sha256.asc -- ${update_url}/SHA256SUMS.sha256.asc
+     -o /host/updates/SHA256SUMS.sha256.asc -- ${update_url}/SHA256SUMS.sha256.asc
-- 
2.51.0


^ permalink raw reply related	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2025-12-12 21:55 UTC | newest]

Thread overview: 2+ messages (download: mbox.gz follow: Atom feed
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2025-12-12 21:54 [PATCH 1/2] img/app: change virtio-fs tag to "host" Alyssa Ross
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