mirror/kde-linux
1
0
Fork 0
mirror of https://github.com/KDE/kde-linux.git synced 2026-08-04 03:02:45 -04:00
Code Issues Packages Projects Releases Wiki Activity

try handeling nested subvols better

Browse Source
This commit is contained in:
Hadi Chokr
2026-04-26 15:50:02 +02:00
parent 17a23d394c
commit efac7ffd1c
1 changed files with 41 additions and 20 deletions
Download Patch File Download Diff File Expand all files Collapse all files

61
btrfs-migrator/src/main.rs
View File

@@ -13,7 +13,7 @@ use std::{
extern crate scopeguard;
use dialoguer::{self, Confirm};
use fstab::FsTab;
use libbtrfsutil::{CreateSnapshotOptions, CreateSubvolumeOptions, DeleteSubvolumeOptions};
use libbtrfsutil::{CreateSnapshotOptions, CreateSubvolumeOptions, DeleteSubvolumeOptions, is_subvolume};
fn find_rootfs_v1(root: &Path) -> Option<PathBuf> {
let subvols = fs::read_dir(root).ok()?;
@@ -240,10 +240,11 @@ If nothing critically important is managed by fstab you can let the auto-migrati
fn run_v3(root: &Path) -> Result<(), Box<dyn Error>> {
let system_home = root.join("@system/home");
let system_home_tmp = root.join("@system/home.v3tmp");
let system_home_old = root.join("@system/home.v3old");
let _ = Command::new("plymouth")
.arg("display-message")
.arg("--text=Migrating to v3 rootfs. Can take a while.")
.status();
.arg("display-message")
.arg("--text=Migrating to v3 rootfs. Can take a while.")
.status();
println!("Migrating @system/home from subvolume to regular directory with per-user subvolumes");
// Stage into a sibling directory so that if we crash mid-way, @system/home is still a subvolume
// and the next boot will retry the migration cleanly.
@@ -257,18 +258,18 @@ fn run_v3(root: &Path) -> Result<(), Box<dyn Error>> {
let dst = system_home_tmp.join(entry.file_name());
println!("Creating user subvolume at {dst:?}");
CreateSubvolumeOptions::new()
.create(&dst)
.map_err(|e| format!("Failed to create subvolume {dst:?}: {e:?}"))?;
.create(&dst)
.map_err(|e| format!("Failed to create subvolume {dst:?}: {e:?}"))?;
// Copy everything except nested subvolume contents (leaves empty placeholder dirs)
// Copy everything except nested subvolume contents (leaves empty dirs)
let cp_result = Command::new("cp")
.arg("--recursive")
.arg("--archive")
.arg("--reflink=auto")
.arg(format!("{}/.", src.display()))
.arg(format!("{}/.", dst.display()))
.status()
.expect("Failed to copy user home");
.arg("--recursive")
.arg("--archive")
.arg("--reflink=auto")
.arg(format!("{}/.", src.display()))
.arg(format!("{}/.", dst.display()))
.status()
.expect("Failed to copy user home");
if !cp_result.success() {
return Err(format!("Failed to copy {src:?} to {dst:?}").into());
}
@@ -282,16 +283,36 @@ fn run_v3(root: &Path) -> Result<(), Box<dyn Error>> {
println!("Snapshotting nested subvolume {nested_src:?} -> {nested_dst:?}");
fs::remove_dir(&nested_dst)?;
CreateSnapshotOptions::new()
.snapshot(&nested_src, &nested_dst)
.map_err(|e| format!("Failed to snapshot {nested_src:?} to {nested_dst:?}: {e:?}"))?;
.recursive(true)
.create(&nested_src, &nested_dst)
.map_err(|e| format!("Failed to snapshot {nested_src:?} to {nested_dst:?}: {e:?}"))?;
}
}
}
DeleteSubvolumeOptions::new()
.delete(&system_home)
.map_err(|e| format!("Failed to delete @system/home subvolume: {e:?}"))?;
// the original subvolume is still intact at home.v3old and can be recovered.
println!("Renaming {system_home:?} to {system_home_old:?}");
fs::rename(&system_home, &system_home_old)?;
println!("Renaming {system_home_tmp:?} to {system_home:?}");
fs::rename(&system_home_tmp, &system_home)?; // fatal problem
if let Err(e) = fs::rename(&system_home_tmp, &system_home) {
// Rename failed
eprintln!("Fatal: failed to rename {system_home_tmp:?} to {system_home:?}: {e}");
eprintln!("Restoring original home subvolume from {system_home_old:?}");
fs::rename(&system_home_old, &system_home)
.map_err(|re| format!("CRITICAL: failed to restore original home: {re}. System may be unbootable. Original home is at {system_home_old:?}"))?;
return Err(format!("Migration failed, original home restored: {e}").into());
}
println!("Deleting old home subvolume {system_home_old:?}");
let _ = DeleteSubvolumeOptions::new()
.recursive(true)
.delete(&system_home_old)
.map_err(|e| {
eprintln!("Warning: failed to delete old home subvolume {system_home_old:?}: {e}");
eprintln!("The migration succeeded but {system_home_old:?} can be manually deleted.");
});
Ok(())
}