From 7239204b0149a2d3d0beedad4cf2f932d5d5ffb4 Mon Sep 17 00:00:00 2001
From: Ming-Hung Tsai <mtsai@redhat.com>
Date: Mon, 19 Jul 2021 11:43:03 +0800
Subject: [PATCH] [cache_repair (rust)] First pass at cache_repair

---
 src/bin/cache_repair.rs | 79 +++++++++++++++++++++++++++++++++++++++++
 src/cache/mod.rs        |  1 +
 src/cache/repair.rs     | 68 +++++++++++++++++++++++++++++++++++
 3 files changed, 148 insertions(+)
 create mode 100644 src/bin/cache_repair.rs
 create mode 100644 src/cache/repair.rs

diff --git a/src/bin/cache_repair.rs b/src/bin/cache_repair.rs
new file mode 100644
index 0000000..d964a0f
--- /dev/null
+++ b/src/bin/cache_repair.rs
@@ -0,0 +1,79 @@
+extern crate clap;
+extern crate thinp;
+
+use atty::Stream;
+use clap::{App, Arg};
+use std::path::Path;
+use std::process;
+use std::process::exit;
+use std::sync::Arc;
+use thinp::cache::repair::{repair, CacheRepairOptions};
+use thinp::file_utils;
+use thinp::report::*;
+
+fn main() {
+    let parser = App::new("cache_repair")
+        .version(thinp::version::tools_version())
+        .about("Repair binary cache metadata, and write it to a different device or file")
+        // flags
+        .arg(
+            Arg::with_name("ASYNC_IO")
+                .help("Force use of io_uring for synchronous io")
+                .long("async-io")
+                .hidden(true),
+        )
+        .arg(
+            Arg::with_name("QUIET")
+                .help("Suppress output messages, return only exit code.")
+                .short("q")
+                .long("quiet"),
+        )
+        // options
+        .arg(
+            Arg::with_name("INPUT")
+                .help("Specify the input device")
+                .short("i")
+                .long("input")
+                .value_name("INPUT")
+                .required(true),
+        )
+        .arg(
+            Arg::with_name("OUTPUT")
+                .help("Specify the output device")
+                .short("o")
+                .long("output")
+                .value_name("OUTPUT")
+                .required(true),
+        );
+
+    let matches = parser.get_matches();
+    let input_file = Path::new(matches.value_of("INPUT").unwrap());
+    let output_file = Path::new(matches.value_of("OUTPUT").unwrap());
+
+    if !file_utils::file_exists(input_file) {
+        eprintln!("Couldn't find input file '{:?}'.", &input_file);
+        exit(1);
+    }
+
+    let report;
+
+    if matches.is_present("QUIET") {
+        report = std::sync::Arc::new(mk_quiet_report());
+    } else if atty::is(Stream::Stdout) {
+        report = std::sync::Arc::new(mk_progress_bar_report());
+    } else {
+        report = Arc::new(mk_simple_report());
+    }
+
+    let opts = CacheRepairOptions {
+        input: &input_file,
+        output: &output_file,
+        async_io: matches.is_present("ASYNC_IO"),
+        report,
+    };
+
+    if let Err(reason) = repair(opts) {
+        eprintln!("{}", reason);
+        process::exit(1);
+    }
+}
diff --git a/src/cache/mod.rs b/src/cache/mod.rs
index c01cc6c..4a90694 100644
--- a/src/cache/mod.rs
+++ b/src/cache/mod.rs
@@ -3,6 +3,7 @@ pub mod dump;
 pub mod hint;
 pub mod ir;
 pub mod mapping;
+pub mod repair;
 pub mod restore;
 pub mod superblock;
 pub mod xml;
diff --git a/src/cache/repair.rs b/src/cache/repair.rs
new file mode 100644
index 0000000..dd88a26
--- /dev/null
+++ b/src/cache/repair.rs
@@ -0,0 +1,68 @@
+use anyhow::Result;
+use std::path::Path;
+use std::sync::Arc;
+
+use crate::cache::dump::*;
+use crate::cache::restore::*;
+use crate::cache::superblock::*;
+use crate::io_engine::*;
+use crate::pdata::space_map::*;
+use crate::report::*;
+use crate::write_batcher::*;
+
+//------------------------------------------
+
+pub struct CacheRepairOptions<'a> {
+    pub input: &'a Path,
+    pub output: &'a Path,
+    pub async_io: bool,
+    pub report: Arc<Report>,
+}
+
+struct Context {
+    _report: Arc<Report>,
+    engine_in: Arc<dyn IoEngine + Send + Sync>,
+    engine_out: Arc<dyn IoEngine + Send + Sync>,
+}
+
+const MAX_CONCURRENT_IO: u32 = 1024;
+
+fn new_context(opts: &CacheRepairOptions) -> Result<Context> {
+    let engine_in: Arc<dyn IoEngine + Send + Sync>;
+    let engine_out: Arc<dyn IoEngine + Send + Sync>;
+
+    if opts.async_io {
+        engine_in = Arc::new(AsyncIoEngine::new(opts.input, MAX_CONCURRENT_IO, true)?);
+        engine_out = Arc::new(AsyncIoEngine::new(opts.output, MAX_CONCURRENT_IO, true)?);
+    } else {
+        let nr_threads = std::cmp::max(8, num_cpus::get() * 2);
+        engine_in = Arc::new(SyncIoEngine::new(opts.input, nr_threads, true)?);
+        engine_out = Arc::new(SyncIoEngine::new(opts.output, nr_threads, true)?);
+    }
+
+    Ok(Context {
+        _report: opts.report.clone(),
+        engine_in,
+        engine_out,
+    })
+}
+
+//------------------------------------------
+
+pub fn repair(opts: CacheRepairOptions) -> Result<()> {
+    let ctx = new_context(&opts)?;
+
+    let sb = read_superblock(ctx.engine_in.as_ref(), SUPERBLOCK_LOCATION)?;
+
+    let sm = core_sm(ctx.engine_out.get_nr_blocks(), u32::MAX);
+    let mut w = WriteBatcher::new(
+        ctx.engine_out.clone(),
+        sm.clone(),
+        ctx.engine_out.get_batch_size(),
+    );
+    let mut restorer = Restorer::new(&mut w);
+
+    dump_metadata(ctx.engine_in, &mut restorer, &sb, true)
+}
+
+//------------------------------------------