composefs-backend: Fix bootc status for BLS complaint bootloader

For BLS complaint bootloaders, just systemd for now, we were still
looking for entries in `boot/loader/entries` which was failing as
entries for these bootloaders will be stored in the ESP.

Also, refactor to use `TempMount::mount_dev` for mounting ESP

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

Author: Johan-Liebert1

crates/lib/src/bootc_composefs/boot.rs

@@ -1,12 +1,12 @@
 use std::fs::create_dir_all;
 use std::io::Write;
-use std::process::Command;
+use std::path::Path;
 use std::{ffi::OsStr, path::PathBuf};
 
 use anyhow::{anyhow, Context, Result};
 use bootc_blockdev::find_parent_devices;
 use bootc_mount::inspect_filesystem;
-use bootc_utils::CommandRunExt;
+use bootc_mount::tempmount::TempMount;
 use camino::{Utf8Path, Utf8PathBuf};
 use cap_std_ext::{
     cap_std::{ambient_authority, fs::Dir},
@@ -272,8 +272,6 @@ struct BLSEntryPath<'a> {
     abs_entries_path: &'a str,
     /// Where to write the .conf files
     config_path: Utf8PathBuf,
-    /// If we mounted EFI, the target path
-    mount_path: Option<Utf8PathBuf>,
 }
 
 /// Sets up and writes BLS entries and binaries (VMLinuz + Initrd) to disk
@@ -352,35 +350,23 @@ pub(crate) fn setup_composefs_bls_boot(
                 entries_path: root_path.join("boot"),
                 config_path: root_path.join("boot"),
                 abs_entries_path: "boot",
-                mount_path: None,
             },
             None,
         ),
 
         Bootloader::Systemd => {
-            let temp_efi_dir = tempfile::tempdir().map_err(|e| {
-                anyhow::anyhow!("Failed to create temporary directory for EFI mount: {e}")
-            })?;
-
-            let mounted_efi = Utf8PathBuf::from_path_buf(temp_efi_dir.path().to_path_buf())
-                .map_err(|_| anyhow::anyhow!("EFI dir is not valid UTF-8"))?;
-
-            Command::new("mount")
-                .args([&PathBuf::from(&esp_device), mounted_efi.as_std_path()])
-                .log_debug()
-                .run_inherited_with_cmd_context()
-                .context("Mounting EFI")?;
+            let efi_mount = TempMount::mount_dev(&esp_device).context("Mounting ESP")?;
 
+            let mounted_efi = Utf8PathBuf::from(efi_mount.dir.path().as_str()?);
             let efi_linux_dir = mounted_efi.join(EFI_LINUX);
 
             (
                 BLSEntryPath {
                     entries_path: efi_linux_dir,
                     config_path: mounted_efi.clone(),
                     abs_entries_path: EFI_LINUX,
-                    mount_path: Some(mounted_efi),
                 },
-                Some(temp_efi_dir),
+                Some(efi_mount),
             )
         }
     };
@@ -518,14 +504,6 @@ pub(crate) fn setup_composefs_bls_boot(
         rustix::fs::fsync(owned_loader_entries_fd).context("fsync")?;
     }
 
-    if let Some(mounted_efi) = entry_paths.mount_path {
-        Command::new("umount")
-            .arg(mounted_efi)
-            .log_debug()
-            .run_inherited_with_cmd_context()
-            .context("Unmounting EFI")?;
-    }
-
     Ok(boot_digest)
 }
 
@@ -537,7 +515,7 @@ fn write_pe_to_esp(
     pe_type: PEType,
     uki_id: &String,
     is_insecure_from_opts: bool,
-    mounted_efi: &PathBuf,
+    mounted_efi: impl AsRef<Path>,
 ) -> Result<Option<String>> {
     let efi_bin = read_file(file, &repo).context("Reading .efi binary")?;
 
@@ -574,7 +552,7 @@ fn write_pe_to_esp(
     }
 
     // Write the UKI to ESP
-    let efi_linux_path = mounted_efi.join(EFI_LINUX);
+    let efi_linux_path = mounted_efi.as_ref().join(EFI_LINUX);
     create_dir_all(&efi_linux_path).context("Creating EFI/Linux")?;
 
     let final_pe_path = match file_path.parent() {
@@ -768,13 +746,7 @@ pub(crate) fn setup_composefs_uki_boot(
         }
     };
 
-    let temp_efi_dir = tempfile::tempdir()
-        .map_err(|e| anyhow::anyhow!("Failed to create temporary directory for EFI mount: {e}"))?;
-    let mounted_efi = temp_efi_dir.path().to_path_buf();
-
-    Task::new("Mounting ESP", "mount")
-        .args([&PathBuf::from(&esp_device), &mounted_efi.clone()])
-        .run()?;
+    let esp_mount = TempMount::mount_dev(&esp_device).context("Mounting ESP")?;
 
     let mut boot_label = String::new();
 
@@ -793,7 +765,7 @@ pub(crate) fn setup_composefs_uki_boot(
                     entry.pe_type,
                     &id.to_hex(),
                     is_insecure_from_opts,
-                    &mounted_efi,
+                    esp_mount.dir.path(),
                 )?;
 
                 if let Some(label) = ret {
@@ -803,12 +775,6 @@ pub(crate) fn setup_composefs_uki_boot(
         };
     }
 
-    Command::new("umount")
-        .arg(&mounted_efi)
-        .log_debug()
-        .run_inherited_with_cmd_context()
-        .context("Unmounting ESP")?;
-
     match bootloader {
         Bootloader::Grub => {
             write_grub_uki_menuentry(root_path, &setup_type, &boot_label, id, &esp_device)?

crates/lib/src/bootc_composefs/status.rs

@@ -1,11 +1,12 @@
-use std::{io::Read, sync::OnceLock};
+use std::{io::Read, sync::OnceLock, u16};
 
 use anyhow::{Context, Result};
 use bootc_kernel_cmdline::utf8::Cmdline;
+use bootc_mount::tempmount::TempMount;
 use fn_error_context::context;
 
 use crate::{
-    bootc_composefs::boot::BootType,
+    bootc_composefs::boot::{get_esp_partition, get_sysroot_parent_dev, BootType},
     composefs_consts::{BOOT_LOADER_ENTRIES, COMPOSEFS_CMDLINE, USER_CFG},
     parsers::{
         bls_config::{parse_bls_config, BLSConfig},
@@ -351,7 +352,27 @@ pub(crate) async fn composefs_deployment_status() -> Result<Host> {
         anyhow::bail!("Could not determine boot type");
     };
 
-    let boot_dir = sysroot.open_dir("boot").context("Opening boot dir")?;
+    let booted = host.require_composefs_booted()?;
+
+    let (boot_dir, _temp_guard) = match booted.bootloader {
+        Bootloader::Grub => (sysroot.open_dir("boot").context("Opening boot dir")?, None),
+
+        // TODO: This is redundant as we should already have ESP mounted at `/efi/` accoding to
+        // spec; currently we do not
+        //
+        // See: https://uapi-group.org/specifications/specs/boot_loader_specification/#mount-points
+        Bootloader::Systemd => {
+            let parent = get_sysroot_parent_dev()?;
+            let (esp_part, ..) = get_esp_partition(&parent)?;
+
+            let esp_mount = TempMount::mount_dev(&esp_part)?;
+
+            let dir = esp_mount.fd.try_clone().context("Cloning fd")?;
+            let guard = Some(esp_mount);
+
+            (dir, guard)
+        }
+    };
 
     match boot_type {
         BootType::Bls => {

crates/lib/src/install.rs

@@ -90,7 +90,7 @@ pub(crate) const ARCH_USES_EFI: bool = cfg!(any(target_arch = "x86_64", target_a
 #[cfg(any(feature = "composefs-backend", feature = "install-to-disk"))]
 pub(crate) const ESP_GUID: &str = "C12A7328-F81F-11D2-BA4B-00A0C93EC93B";
 #[cfg(any(feature = "composefs-backend", feature = "install-to-disk"))]
-pub(crate) const DPS_UUID: &str = "6523f8ae-3eb1-4e2a-a05a-18b695ae656f";
+pub(crate) const DPS_UUID: &str = "4f68bce3-e8cd-4db1-96e7-fbcaf984b709";
 
 const DEFAULT_REPO_CONFIG: &[(&str, &str)] = &[
     // Default to avoiding grub2-mkconfig etc.