[PATCH proxmox-backup 1/5] tools: add helper to run fstrim command on path or mountpoint

[Christian Ebner <c.ebner@proxmox.com>]

Runs the fstrim on the filesystem mounted at given mountpoint or path
on the filesystem, allowing to discard unused blocks on the backing
disk. By invoking with `verbose` flag enabled, statistics are
gathered in the output to show on result. Setting `quiet-unsupported`
allows to run the command without error also on filesystems without
support [0].

With the intention to run this as scheduled job on a datastore's
backing filesystem.

[0] https://www.man7.org/linux/man-pages/man8/fstrim.8.html

Signed-off-by: Christian Ebner <c.ebner@proxmox.com>
---
 src/tools/disks/mod.rs | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/tools/disks/mod.rs b/src/tools/disks/mod.rs
index a86cbdf79..a5cb091a7 100644
--- a/src/tools/disks/mod.rs
+++ b/src/tools/disks/mod.rs
@@ -1392,3 +1392,13 @@ pub fn unmount_by_mountpoint(path: &Path) -> Result<(), Error> {
     proxmox_sys::command::run_command(command, None)?;
     Ok(())
 }
+
+/// Run fstrim on mounted filesystem backing given path.
+pub fn fstrim(path: &Path) -> Result<String, Error> {
+    let mut command = std::process::Command::new("fstrim");
+    command.arg(path);
+    command.arg("--verbose");
+    command.arg("--quiet-unsupported");
+
+    proxmox_sys::command::run_command(command, Some(|exit_code| exit_code == 0))
+}
-- 
2.47.3