composefs: Add option to reset soft reboot state

Signed-off-by: Pragyan Poudyal <pragyanpoudyal41999@gmail.com>

crates/lib/src/bootc_composefs/soft_reboot.rs

@@ -10,25 +10,70 @@ use bootc_initramfs_setup::setup_root;
 use bootc_kernel_cmdline::utf8::Cmdline;
 use bootc_mount::{PID1, bind_mount_from_pidns};
 use camino::Utf8Path;
+use cap_std_ext::cap_std::ambient_authority;
+use cap_std_ext::cap_std::fs::Dir;
+use cap_std_ext::dirext::CapStdExtDirExt;
 use fn_error_context::context;
 use ostree_ext::systemd_has_soft_reboot;
+use rustix::mount::{unmount, UnmountFlags};
 use std::{fs::create_dir_all, os::unix::process::CommandExt, path::PathBuf, process::Command};
 
 const NEXTROOT: &str = "/run/nextroot";
 
+#[context("Resetting soft reboot state")]
+fn reset_soft_reboot() -> Result<()> {
+    let run = Utf8Path::new("/run");
+    bind_mount_from_pidns(PID1, &run, &run, true).context("Bind mounting /run")?;
+
+    let run_dir = Dir::open_ambient_dir("/run", ambient_authority()).context("Opening run")?;
+
+    let nextroot = run_dir
+        .open_dir_optional("nextroot")
+        .context("Opening nextroot")?;
+
+    let Some(nextroot) = nextroot else {
+        tracing::debug!("Nextroot is not a directory");
+        println!("No deployment staged for soft rebooting");
+        return Ok(());
+    };
+
+    let nextroot_mounted = nextroot
+        .is_mountpoint(".")?
+        .ok_or_else(|| anyhow::anyhow!("Failed to get mount info"))?;
+
+    if !nextroot_mounted {
+        tracing::debug!("Nextroot is not a mountpoint");
+        println!("No deployment staged for soft rebooting");
+        return Ok(());
+    }
+
+    unmount(NEXTROOT, UnmountFlags::DETACH).context("Unmounting nextroot")?;
+
+    println!("Soft reboot state cleared successfully");
+
+    Ok(())
+}
+
 /// Checks if the provided deployment is soft reboot capable, and soft reboots the system if
 /// argument `reboot` is true
 #[context("Soft rebooting")]
 pub(crate) async fn prepare_soft_reboot_composefs(
     storage: &Storage,
     booted_cfs: &BootedComposefs,
-    deployment_id: &String,
+    deployment_id: Option<&String>,
     reboot: bool,
+    reset: bool,
 ) -> Result<()> {
     if !systemd_has_soft_reboot() {
         anyhow::bail!("System does not support soft reboots")
     }
 
+    if reset {
+        return reset_soft_reboot();
+    }
+
+    let deployment_id = deployment_id.ok_or_else(|| anyhow::anyhow!("Expected deployment id"))?;
+
     if *deployment_id == *booted_cfs.cmdline.digest {
         anyhow::bail!("Cannot soft-reboot to currently booted deployment");
     }

crates/lib/src/bootc_composefs/update.rs

@@ -267,7 +267,7 @@ pub(crate) async fn do_upgrade(
     }
 
     if opts.soft_reboot.is_some() {
-        prepare_soft_reboot_composefs(storage, booted_cfs, &id.to_hex(), true).await?;
+        prepare_soft_reboot_composefs(storage, booted_cfs, Some(&id.to_hex()), true, false).await?;
     }
 
     Ok(())

crates/lib/src/cli.rs

@@ -618,8 +618,12 @@ pub(crate) enum InternalsOpts {
     /// Dump CLI structure as JSON for documentation generation
     DumpCliJson,
     PrepSoftReboot {
-        deployment: String,
-        #[clap(long)]
+        #[clap(required_unless_present = "reset")]
+        deployment: Option<String>,
+        #[clap(long, conflicts_with = "reset")]
+        reboot: bool,
+        #[clap(long, conflicts_with = "reboot")]
+        reset: bool,
         reboot: bool,
     },
 }
@@ -1836,7 +1840,11 @@ async fn run_from_opt(opt: Opt) -> Result<()> {
 
                 Ok(())
             }
-            InternalsOpts::PrepSoftReboot { deployment, reboot } => {
+            InternalsOpts::PrepSoftReboot {
+                deployment,
+                reboot,
+                reset,
+            } => {
                 let storage = &get_storage().await?;
 
                 match storage.kind()? {
@@ -1845,8 +1853,14 @@ async fn run_from_opt(opt: Opt) -> Result<()> {
                         anyhow::bail!("soft-reboot only implemented for composefs")
                     }
                     BootedStorageKind::Composefs(booted_cfs) => {
-                        prepare_soft_reboot_composefs(&storage, &booted_cfs, &deployment, reboot)
-                            .await
+                        prepare_soft_reboot_composefs(
+                            &storage,
+                            &booted_cfs,
+                            deployment.as_ref(),
+                            reboot,
+                            reset,
+                        )
+                        .await
                     }
                 }
             }