From e762cf6634e4402c4db78438e9afe56eb53e5321 Mon Sep 17 00:00:00 2001
From: Colin Walters <walters@verbum.org>
Date: Fri, 12 Jul 2024 14:08:12 -0400
Subject: [PATCH] [draft] bootloader: Use lsblk

Signed-off-by: Colin Walters <walters@verbum.org>
---
 lib/src/bootloader.rs       | 51 +++++++++++++++++--------------------
 lib/src/install/baseline.rs |  2 +-
 2 files changed, 24 insertions(+), 29 deletions(-)

diff --git a/lib/src/bootloader.rs b/lib/src/bootloader.rs
index b8b1b557..80d203ad 100644
--- a/lib/src/bootloader.rs
+++ b/lib/src/bootloader.rs
@@ -1,13 +1,31 @@
-use std::process::Command;
-use std::str;
 use anyhow::Result;
-use camino::Utf8Path;
+use camino::{Utf8Path, Utf8PathBuf};
 use fn_error_context::context;
 
 use crate::task::Task;
 
 /// The name of the mountpoint for efi (as a subdirectory of /boot, or at the toplevel)
 pub(crate) const EFI_DIR: &str = "efi";
+pub(crate) const PREPBOOT_LABEL: &str = "PowerPC-PReP-boot";
+
+/// Find the device to pass to bootupd. Only on powerpc64 right now
+/// we explicitly find one with a specific label.
+///
+/// This should get fixed once we execute on https://github.com/coreos/bootupd/issues/432
+fn get_bootupd_device(device: &Utf8Path) -> Result<Utf8PathBuf> {
+    #[cfg(target_arch = "powerpc64")]
+    {
+        return crate::blockdev::list_dev(device)?
+            .children
+            .unwrap_or_default()
+            .into_iter()
+            .find(|dev| dev.label.as_deref() == Some(PREPBOOT_LABEL))
+            .ok_or_else(|| anyhow::anyhow!("Failed to find partition with label {PREPBOOT_LABEL}"))
+            .map(|dev| dev.path().into());
+    }
+    #[cfg(not(target_arch = "powerpc64"))]
+    return Ok(device.to_owned());
+}
 
 #[context("Installing bootloader")]
 pub(crate) fn install_via_bootupd(
@@ -15,39 +33,16 @@ pub(crate) fn install_via_bootupd(
     rootfs: &Utf8Path,
     configopts: &crate::install::InstallConfigOpts,
 ) -> Result<()> {
-    let device_str: &str;
-    let prepboot_dir;
     let verbose = std::env::var_os("BOOTC_BOOTLOADER_DEBUG").map(|_| "-vvvv");
     // bootc defaults to only targeting the platform boot method.
     let bootupd_opts = (!configopts.generic_image).then_some(["--update-firmware", "--auto"]);
 
-    if cfg!(target_arch = "powerpc64") {
-        // get PowerPC-PReP-boot device information
-        let result = Command::new("lsblk")
-            .args([
-                "--noheadings",
-                "--paths",
-                "--filter",
-                &(format!(r#"'PARTLABEL=="PowerPC-PReP-boot"'"#)),
-                "--output",
-                &(format!("NAME")),
-            ])
-            .arg(device)
-            .output()?;
-        if !result.status.success() {
-            println!("{}", String::from_utf8_lossy(&result.stderr));
-            anyhow::bail!("lsblkh failed with {}", result.status);
-        }
-        prepboot_dir = String::from_utf8(result.stdout)?;
-        device_str = prepboot_dir.trim();
-    } else {
-        device_str = device.as_str()
-    }
+    let target_device = get_bootupd_device(device)?;
     let args = ["backend", "install", "--write-uuid"]
         .into_iter()
         .chain(verbose)
         .chain(bootupd_opts.iter().copied().flatten())
-        .chain(["--device", device_str, rootfs.as_str()]);
+        .chain(["--device", target_device.as_str(), rootfs.as_str()]);
     Task::new("Running bootupctl to install bootloader", "bootupctl")
         .args(args)
         .verbose()
diff --git a/lib/src/install/baseline.rs b/lib/src/install/baseline.rs
index f60c6bc6..09661ecd 100644
--- a/lib/src/install/baseline.rs
+++ b/lib/src/install/baseline.rs
@@ -265,7 +265,7 @@ pub(crate) fn install_create_rootfs(
             &mut sgdisk.cmd,
             partno,
             "0:+4M",
-            "PowerPC-PReP-boot",
+            crate::bootloader::PREPBOOT_LABEL,
             Some("9E1A2D38-C612-4316-AA26-8B49521E5A8B"),
         );
     } else {