ksud: retry for mount

userspace/ksud/Cargo.lock

@@ -336,6 +336,17 @@ dependencies = [
  "version_check",
 ]
 
+[[package]]
+name = "getrandom"
+version = "0.2.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c05aeb6a22b8f62540c194aac980f2115af067bfe15a0734d7277a768d396b31"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "wasi 0.11.0+wasi-snapshot-preview1",
+]
+
 [[package]]
 name = "heck"
 version = "0.4.0"
@@ -426,6 +437,7 @@ dependencies = [
  "java-properties",
  "log",
  "regex",
+ "retry",
  "serde",
  "serde_json",
  "subprocess",
@@ -522,6 +534,12 @@ version = "0.3.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6ac9a59f73473f1b8d852421e59e64809f025994837ef743615c6d0c5b305160"
 
+[[package]]
+name = "ppv-lite86"
+version = "0.2.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5b40af805b3121feab8a3c29f04d8ad262fa8e0561883e7653e024ae4479e6de"
+
 [[package]]
 name = "proc-macro-error"
 version = "1.0.4"
@@ -564,11 +582,35 @@ dependencies = [
  "proc-macro2",
 ]
 
+[[package]]
+name = "rand"
+version = "0.8.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "34af8d1a0e25924bc5b7c43c079c942339d8f0a8b57c39049bef581b46327404"
+dependencies = [
+ "libc",
+ "rand_chacha",
+ "rand_core",
+]
+
+[[package]]
+name = "rand_chacha"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6c10a63a0fa32252be49d21e7709d4d4baf8d231c2dbce1eaa8141b9b127d88"
+dependencies = [
+ "ppv-lite86",
+ "rand_core",
+]
+
 [[package]]
 name = "rand_core"
 version = "0.6.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ec0be4795e2f6a28069bec0b5ff3e2ac9bafc99e6a9a7dc3547996c5c816922c"
+dependencies = [
+ "getrandom",
+]
 
 [[package]]
 name = "regex"
@@ -587,6 +629,15 @@ version = "0.6.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "456c603be3e8d448b072f410900c09faf164fbce2d480456f50eea6e25f9c848"
 
+[[package]]
+name = "retry"
+version = "2.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9166d72162de3575f950507683fac47e30f6f2c3836b71b7fbc61aa517c9c5f4"
+dependencies = [
+ "rand",
+]
+
 [[package]]
 name = "rustix"
 version = "0.36.6"
@@ -715,7 +766,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1b797afad3f312d1c66a56d11d0316f916356d11bd158fbc6ca6389ff6bf805a"
 dependencies = [
  "libc",
- "wasi",
+ "wasi 0.10.0+wasi-snapshot-preview1",
  "winapi",
 ]
 
@@ -776,6 +827,12 @@ version = "0.10.0+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1a143597ca7c7793eff794def352d41792a93c481eb1042423ff7ff72ba2c31f"
 
+[[package]]
+name = "wasi"
+version = "0.11.0+wasi-snapshot-preview1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"
+
 [[package]]
 name = "winapi"
 version = "0.3.9"

userspace/ksud/Cargo.toml

@@ -20,6 +20,7 @@ serde = { version = "1.0" }
 serde_json = "1.0"
 regex = "1.5.4"
 encoding = "0.2.33"
+retry = "2.0.0"
 
 [profile.release]
 strip = true

userspace/ksud/src/utils.rs

@@ -4,11 +4,20 @@ use std::{
 };
 
 use anyhow::{ensure, Result};
+use retry::delay::NoDelay;
 use subprocess::Exec;
 
-pub fn mount_image(src: &str, target: &str) -> Result<()> {
+fn do_mount_image(src: &str, target: &str) -> Result<()> {
     let result = Exec::shell(format!("mount -t ext4 {} {}", src, target)).join()?;
-    ensure!(result.success(), "mount: {} -> {} failed.", src, target);
+    ensure!(result.success(), "do mount: {} -> {} failed.", src, target);
+    Ok(())
+}
+
+pub fn mount_image(src: &str, target: &str) -> Result<()> {
+    // umount target first.
+    let _ = umount_dir(target);
+    let a = retry::retry(NoDelay.take(3), || do_mount_image(src, target));
+    ensure!(a.is_ok(), "mount: {} -> {} failed.", src, target);
     Ok(())
 }