thin-provisioning-tools/tests/thin_shrink.rs
Joe Thornber 32019ac388 [thin_shrink] add a trivial snapshot test.
Still need much more work on snap tests.
2020-07-22 16:07:34 +01:00

935 lines
23 KiB
Rust

use anyhow::{anyhow, Result};
use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
use rand::prelude::*;
use std::collections::VecDeque;
use std::fs::OpenOptions;
use std::io::{Cursor, Read, Seek, SeekFrom, Write};
use std::ops::Range;
use std::path::{Path, PathBuf};
use tempfile::tempdir;
use thinp::file_utils;
use thinp::thin::xml::{self, Visit};
//------------------------------------
#[derive(Debug)]
struct ThinBlock {
thin_id: u32,
thin_block: u64,
data_block: u64,
block_size: usize,
}
struct ThinReadRef {
pub data: Vec<u8>,
}
struct ThinWriteRef<'a, W: Write + Seek> {
file: &'a mut W,
block_byte: u64,
pub data: Vec<u8>,
}
impl ThinBlock {
fn read_ref<R: Read + Seek>(&self, r: &mut R) -> Result<ThinReadRef> {
let mut rr = ThinReadRef {
data: vec![0; self.block_size * 512],
};
let byte = self.data_block * (self.block_size as u64) * 512;
r.seek(SeekFrom::Start(byte))?;
r.read_exact(&mut rr.data)?;
Ok(rr)
}
fn zero_ref<'a, W: Write + Seek>(&self, w: &'a mut W) -> ThinWriteRef<'a, W> {
ThinWriteRef {
file: w,
block_byte: self.data_block * (self.block_size as u64) * 512,
data: vec![0; self.block_size * 512],
}
}
//fn write_ref<'a, W>(&self, w: &'a mut W) -> Result<ThinWriteRef<'a, W>>
//where
//W: Read + Write + Seek,
//{
//let mut data = vec![0; self.block_size];
//w.seek(SeekFrom::Start(self.data_block * (self.block_size as u64)))?;
//w.read_exact(&mut data[0..])?;
//
//let wr = ThinWriteRef {
//file: w,
//block_byte: self.data_block * (self.block_size as u64),
//data: vec![0; self.block_size],
//};
//
//Ok(wr)
//}
}
impl<'a, W: Write + Seek> Drop for ThinWriteRef<'a, W> {
fn drop(&mut self) {
// FIXME: We shouldn't panic in a drop function, so any IO
// errors will have to make their way back to the user
// another way (eg, via a flush() method).
self.file.seek(SeekFrom::Start(self.block_byte)).unwrap();
self.file.write_all(&self.data).unwrap();
}
}
//------------------------------------
trait ThinVisitor {
fn thin_block(&mut self, tb: &ThinBlock) -> Result<()>;
}
struct ThinXmlVisitor<'a, V: ThinVisitor> {
inner: &'a mut V,
block_size: Option<u32>,
thin_id: Option<u32>,
}
impl<'a, V: ThinVisitor> xml::MetadataVisitor for ThinXmlVisitor<'a, V> {
fn superblock_b(&mut self, sb: &xml::Superblock) -> Result<Visit> {
self.block_size = Some(sb.data_block_size);
Ok(Visit::Continue)
}
fn superblock_e(&mut self) -> Result<Visit> {
Ok(Visit::Continue)
}
fn device_b(&mut self, d: &xml::Device) -> Result<Visit> {
self.thin_id = Some(d.dev_id);
Ok(Visit::Continue)
}
fn device_e(&mut self) -> Result<Visit> {
Ok(Visit::Continue)
}
fn map(&mut self, m: &xml::Map) -> Result<Visit> {
for i in 0..m.len {
let block = ThinBlock {
thin_id: self.thin_id.unwrap(),
thin_block: m.thin_begin + i,
data_block: m.data_begin + i,
block_size: self.block_size.unwrap() as usize,
};
self.inner.thin_block(&block)?;
}
Ok(Visit::Continue)
}
fn eof(&mut self) -> Result<Visit> {
Ok(Visit::Stop)
}
}
fn thin_visit<R, M>(input: R, visitor: &mut M) -> Result<()>
where
R: Read,
M: ThinVisitor,
{
let mut xml_visitor = ThinXmlVisitor {
inner: visitor,
block_size: None,
thin_id: None,
};
xml::read(input, &mut xml_visitor)
}
//------------------------------------
// To test thin_shrink we'd like to stamp a known pattern across the
// provisioned areas of the thins in the pool, do the shrink, verify
// the patterns.
// A simple linear congruence generator used to create the data to
// go into the thin blocks.
struct Generator {
x: u64,
a: u64,
c: u64,
}
impl Generator {
fn new() -> Generator {
Generator {
x: 0,
a: 6364136223846793005,
c: 1442695040888963407,
}
}
fn step(&mut self) {
self.x = self.a.wrapping_mul(self.x).wrapping_add(self.c)
}
fn fill_buffer(&mut self, seed: u64, bytes: &mut [u8]) -> Result<()> {
self.x = seed;
assert!(bytes.len() % 8 == 0);
let nr_words = bytes.len() / 8;
let mut out = Cursor::new(bytes);
for _ in 0..nr_words {
out.write_u64::<LittleEndian>(self.x)?;
self.step();
}
Ok(())
}
fn verify_buffer(&mut self, seed: u64, bytes: &[u8]) -> Result<bool> {
self.x = seed;
assert!(bytes.len() % 8 == 0);
let nr_words = bytes.len() / 8;
let mut input = Cursor::new(bytes);
for _ in 0..nr_words {
let w = input.read_u64::<LittleEndian>()?;
if w != self.x {
eprintln!("{} != {}", w, self.x);
return Ok(false);
}
self.step();
}
Ok(true)
}
}
//------------------------------------
struct Stamper<'a, W: Write + Seek> {
data_file: &'a mut W,
seed: u64,
}
impl<'a, W: Write + Seek> Stamper<'a, W> {
fn new(w: &'a mut W, seed: u64) -> Stamper<'a, W> {
Stamper { data_file: w, seed }
}
}
impl<'a, W: Write + Seek> ThinVisitor for Stamper<'a, W> {
fn thin_block(&mut self, b: &ThinBlock) -> Result<()> {
let mut wr = b.zero_ref(self.data_file);
let mut gen = Generator::new();
gen.fill_buffer(self.seed ^ (b.thin_id as u64) ^ b.thin_block, &mut wr.data)?;
Ok(())
}
}
//------------------------------------
struct Verifier<'a, R: Read + Seek> {
data_file: &'a mut R,
seed: u64,
}
impl<'a, R: Read + Seek> Verifier<'a, R> {
fn new(r: &'a mut R, seed: u64) -> Verifier<'a, R> {
Verifier { data_file: r, seed }
}
}
impl<'a, R: Read + Seek> ThinVisitor for Verifier<'a, R> {
fn thin_block(&mut self, b: &ThinBlock) -> Result<()> {
let rr = b.read_ref(self.data_file)?;
let mut gen = Generator::new();
if !gen.verify_buffer(self.seed ^ (b.thin_id as u64) ^ b.thin_block, &rr.data)? {
return Err(anyhow!("data verify failed for {:?}", b));
}
Ok(())
}
}
//------------------------------------
fn mk_path(dir: &Path, file: &str) -> PathBuf {
let mut p = PathBuf::new();
p.push(dir);
p.push(PathBuf::from(file));
p
}
fn generate_xml(path: &Path, g: &mut dyn Scenario) -> Result<()> {
let xml_out = OpenOptions::new()
.read(false)
.write(true)
.create(true)
.truncate(true)
.open(path)?;
let mut w = xml::XmlWriter::new(xml_out);
g.generate_xml(&mut w)
}
fn create_data_file(data_path: &Path, xml_path: &Path) -> Result<()> {
let input = OpenOptions::new().read(true).write(false).open(xml_path)?;
let sb = xml::read_superblock(input)?;
let nr_blocks = sb.nr_data_blocks as u64;
let block_size = sb.data_block_size as u64 * 512;
let _file = file_utils::create_sized_file(data_path, nr_blocks * block_size)?;
Ok(())
}
fn stamp(xml_path: &Path, data_path: &Path, seed: u64) -> Result<()> {
let mut data = OpenOptions::new()
.read(false)
.write(true)
.open(&data_path)?;
let xml = OpenOptions::new().read(true).write(false).open(&xml_path)?;
let mut stamper = Stamper::new(&mut data, seed);
thin_visit(xml, &mut stamper)
}
fn verify(xml_path: &Path, data_path: &Path, seed: u64) -> Result<()> {
let mut data = OpenOptions::new()
.read(true)
.write(false)
.open(&data_path)?;
let xml = OpenOptions::new().read(true).write(false).open(&xml_path)?;
let mut verifier = Verifier::new(&mut data, seed);
thin_visit(xml, &mut verifier)
}
trait Scenario {
fn generate_xml(&mut self, v: &mut dyn xml::MetadataVisitor) -> Result<()>;
fn get_new_nr_blocks(&self) -> u64;
}
fn test_shrink(scenario: &mut dyn Scenario) -> Result<()> {
let dir = tempdir()?;
let xml_before = mk_path(dir.path(), "before.xml");
let xml_after = mk_path(dir.path(), "after.xml");
let data_path = mk_path(dir.path(), "metadata.bin");
generate_xml(&xml_before, scenario)?;
create_data_file(&data_path, &xml_before)?;
let mut rng = rand::thread_rng();
let seed = rng.gen::<u64>();
stamp(&xml_before, &data_path, seed)?;
verify(&xml_before, &data_path, seed)?;
let new_nr_blocks = scenario.get_new_nr_blocks();
thinp::shrink::toplevel::shrink(&xml_before, &xml_after, &data_path, new_nr_blocks, true)?;
verify(&xml_after, &data_path, seed)?;
Ok(())
}
//------------------------------------
fn common_sb(nr_blocks: u64) -> xml::Superblock {
xml::Superblock {
uuid: "".to_string(),
time: 0,
transaction: 0,
flags: None,
version: None,
data_block_size: 32,
nr_data_blocks: nr_blocks,
metadata_snap: None,
}
}
struct EmptyPoolS {}
impl Scenario for EmptyPoolS {
fn generate_xml(&mut self, v: &mut dyn xml::MetadataVisitor) -> Result<()> {
v.superblock_b(&common_sb(1024))?;
v.superblock_e()?;
Ok(())
}
fn get_new_nr_blocks(&self) -> u64 {
512
}
}
#[test]
fn shrink_empty_pool() -> Result<()> {
let mut s = EmptyPoolS {};
test_shrink(&mut s)
}
//------------------------------------
struct SingleThinS {
offset: u64,
len: u64,
old_nr_data_blocks: u64,
new_nr_data_blocks: u64,
}
impl SingleThinS {
fn new(offset: u64, len: u64, old_nr_data_blocks: u64, new_nr_data_blocks: u64) -> Self {
SingleThinS {
offset,
len,
old_nr_data_blocks,
new_nr_data_blocks,
}
}
}
impl Scenario for SingleThinS {
fn generate_xml(&mut self, v: &mut dyn xml::MetadataVisitor) -> Result<()> {
v.superblock_b(&common_sb(self.old_nr_data_blocks))?;
v.device_b(&xml::Device {
dev_id: 0,
mapped_blocks: self.len,
transaction: 0,
creation_time: 0,
snap_time: 0,
})?;
v.map(&xml::Map {
thin_begin: 0,
data_begin: self.offset,
time: 0,
len: self.len,
})?;
v.device_e()?;
v.superblock_e()?;
Ok(())
}
fn get_new_nr_blocks(&self) -> u64 {
self.new_nr_data_blocks
}
}
#[test]
fn shrink_single_no_move_1() -> Result<()> {
let mut s = SingleThinS::new(0, 1024, 2048, 1280);
test_shrink(&mut s)
}
#[test]
fn shrink_single_no_move_2() -> Result<()> {
let mut s = SingleThinS::new(100, 1024, 2048, 1280);
test_shrink(&mut s)
}
#[test]
fn shrink_single_no_move_3() -> Result<()> {
let mut s = SingleThinS::new(1024, 1024, 2048, 2048);
test_shrink(&mut s)
}
#[test]
fn shrink_single_partial_move() -> Result<()> {
let mut s = SingleThinS::new(1024, 1024, 2048, 1280);
test_shrink(&mut s)
}
#[test]
fn shrink_single_total_move() -> Result<()> {
let mut s = SingleThinS::new(2048, 1024, 1024 + 2048, 1280);
test_shrink(&mut s)
}
#[test]
fn shrink_insufficient_space() -> Result<()> {
let mut s = SingleThinS::new(0, 2048, 3000, 1280);
match test_shrink(&mut s) {
Ok(_) => Err(anyhow!("Shrink unexpectedly succeeded")),
Err(_) => Ok(()),
}
}
//------------------------------------
struct FragmentedS {
nr_thins: u32,
thin_size: u64,
old_nr_data_blocks: u64,
new_nr_data_blocks: u64,
}
impl FragmentedS {
fn new(nr_thins: u32, thin_size: u64) -> Self {
let old_size = (nr_thins as u64) * thin_size;
FragmentedS {
nr_thins,
thin_size,
old_nr_data_blocks: (nr_thins as u64) * thin_size,
new_nr_data_blocks: old_size * 3 / 4,
}
}
}
#[derive(Clone)]
struct ThinRun {
thin_id: u32,
thin_begin: u64,
len: u64,
}
#[derive(Clone, Debug, Copy)]
struct MappedRun {
thin_id: u32,
thin_begin: u64,
data_begin: u64,
len: u64,
}
fn mk_runs(thin_id: u32, total_len: u64, run_len: std::ops::Range<u64>) -> Vec<ThinRun> {
let mut runs = Vec::new();
let mut b = 0u64;
while b < total_len {
let len = u64::min(
total_len - b,
thread_rng().gen_range(run_len.start, run_len.end),
);
runs.push(ThinRun {
thin_id: thin_id,
thin_begin: b,
len,
});
b += len;
}
runs
}
impl Scenario for FragmentedS {
fn generate_xml(&mut self, v: &mut dyn xml::MetadataVisitor) -> Result<()> {
// Allocate each thin fully, in runs between 1 and 16.
let mut runs = Vec::new();
for thin in 0..self.nr_thins {
runs.append(&mut mk_runs(thin, self.thin_size, 1..17));
}
// Shuffle
runs.shuffle(&mut rand::thread_rng());
// map across the data
let mut maps = Vec::new();
let mut b = 0;
for r in &runs {
maps.push(MappedRun {
thin_id: r.thin_id,
thin_begin: r.thin_begin,
data_begin: b,
len: r.len,
});
b += r.len;
}
// drop half the mappings, which leaves us free runs
let mut dropped = Vec::new();
for i in 0..maps.len() {
if i % 2 == 0 {
dropped.push(maps[i].clone());
}
}
// Unshuffle. This isn't strictly necc. but makes the xml
// more readable.
use std::cmp::Ordering;
maps.sort_by(|&l, &r| match l.thin_id.cmp(&r.thin_id) {
Ordering::Equal => l.thin_begin.cmp(&r.thin_begin),
o => o,
});
// write the xml
v.superblock_b(&common_sb(self.old_nr_data_blocks))?;
for thin in 0..self.nr_thins {
v.device_b(&xml::Device {
dev_id: thin,
mapped_blocks: self.thin_size,
transaction: 0,
creation_time: 0,
snap_time: 0,
})?;
for m in &dropped {
if m.thin_id != thin {
continue;
}
v.map(&xml::Map {
thin_begin: m.thin_begin,
data_begin: m.data_begin,
time: 0,
len: m.len,
})?;
}
v.device_e()?;
}
v.superblock_e()?;
Ok(())
}
fn get_new_nr_blocks(&self) -> u64 {
self.new_nr_data_blocks
}
}
#[test]
fn shrink_fragmented_thin_1() -> Result<()> {
let mut s = FragmentedS::new(1, 2048);
test_shrink(&mut s)
}
#[test]
fn shrink_fragmented_thin_2() -> Result<()> {
let mut s = FragmentedS::new(2, 2048);
test_shrink(&mut s)
}
#[test]
fn shrink_fragmented_thin_8() -> Result<()> {
let mut s = FragmentedS::new(2, 2048);
test_shrink(&mut s)
}
#[test]
fn shrink_fragmented_thin_64() -> Result<()> {
let mut s = FragmentedS::new(2, 2048);
test_shrink(&mut s)
}
//------------------------------------
struct Allocator {
runs: VecDeque<Range<u64>>,
}
impl Allocator {
fn new_shuffled(total_len: u64, run_len: Range<u64>) -> Allocator {
let mut runs = Vec::new();
let mut b = 0u64;
while b < total_len {
let len = u64::min(
total_len - b,
thread_rng().gen_range(run_len.start, run_len.end),
);
runs.push(b..(b + len));
b += len;
}
runs.shuffle(&mut thread_rng());
let runs: VecDeque<Range<u64>> = runs.iter().map(|r| r.clone()).collect();
Allocator { runs }
}
fn is_empty(&self) -> bool {
self.runs.is_empty()
}
fn alloc(&mut self, len: u64) -> Result<Vec<Range<u64>>> {
let mut len = len;
let mut runs = Vec::new();
while len > 0 {
let r = self.runs.pop_front();
if r.is_none() {
return Err(anyhow!("could not allocate; out of space"));
}
let mut r = r.unwrap();
let rlen = r.end - r.start;
if len < rlen {
runs.push(r.start..(r.start + len));
// We need to push something back.
self.runs.push_front((r.start + len)..r.end);
len = 0;
} else {
runs.push(r.start..r.end);
len -= rlen;
}
}
Ok(runs)
}
}
// Having explicitly unmapped regions makes it easier to
// apply snapshots.
#[derive(Clone)]
enum Run {
Mapped { data_begin: u64, len: u64 },
UnMapped { len: u64 },
}
impl Run {
fn len(&self) -> u64 {
match self {
Run::Mapped {
data_begin: _data_begin,
len,
} => *len,
Run::UnMapped { len } => *len,
}
}
fn split(&self, n: u64) -> (Option<Run>, Option<Run>) {
if n == 0 {
return (None, Some(self.clone()));
} else {
if self.len() <= n {
return (Some(self.clone()), None);
} else {
match self {
Run::Mapped { data_begin, len } => (
Some(Run::Mapped {
data_begin: *data_begin,
len: n,
}),
Some(Run::Mapped {
data_begin: data_begin + n,
len: len - n,
}),
),
Run::UnMapped { len } => (
Some(Run::UnMapped { len: n }),
Some(Run::UnMapped { len: len - n }),
),
}
}
}
}
}
#[derive(Clone)]
struct ThinDev {
thin_id: u32,
dev_size: u64,
runs: Vec<Run>,
}
impl ThinDev {
fn emit(&self, v: &mut dyn xml::MetadataVisitor) -> Result<()> {
v.device_b(&xml::Device {
dev_id: self.thin_id,
mapped_blocks: self.dev_size,
transaction: 0,
creation_time: 0,
snap_time: 0,
})?;
let mut b = 0;
for r in &self.runs {
match r {
Run::Mapped { data_begin, len } => {
v.map(&xml::Map {
thin_begin: b,
data_begin: *data_begin,
time: 0,
len: *len,
})?;
b += len;
}
Run::UnMapped { len } => {
b += len;
}
}
}
v.device_e()?;
Ok(())
}
}
#[derive(Clone)]
enum SnapRunType {
Same,
Diff,
Hole,
}
#[derive(Clone)]
struct SnapRun(SnapRunType, u64);
fn mk_origin(thin_id: u32, total_len: u64, allocator: &mut Allocator) -> Result<ThinDev> {
let mut runs = Vec::new();
let mut b = 0;
while b < total_len {
let len = u64::min(thread_rng().gen_range(16, 64), total_len - b);
match thread_rng().gen_range(0, 2) {
0 => {
for data in allocator.alloc(len)? {
assert!(data.end >= data.start);
runs.push(Run::Mapped {
data_begin: data.start,
len: data.end - data.start,
});
}
}
1 => {
runs.push(Run::UnMapped { len });
}
_ => {
return Err(anyhow!("bad value returned from rng"));
}
};
b += len;
}
Ok(ThinDev {
thin_id,
dev_size: total_len,
runs,
})
}
fn mk_snap_mapping(
total_len: u64,
run_len: Range<u64>,
same_percent: usize,
diff_percent: usize,
) -> Vec<SnapRun> {
let mut runs = Vec::new();
let mut b = 0u64;
while b < total_len {
let len = u64::min(
total_len - b,
thread_rng().gen_range(run_len.start, run_len.end),
);
let n = thread_rng().gen_range(0, 100);
if n < same_percent {
runs.push(SnapRun(SnapRunType::Same, len));
} else if n < diff_percent {
runs.push(SnapRun(SnapRunType::Diff, len));
} else {
runs.push(SnapRun(SnapRunType::Hole, len));
}
b += len;
}
runs
}
fn split_runs(mut n: u64, runs: &Vec<Run>) -> (Vec<Run>, Vec<Run>) {
let mut before = Vec::new();
let mut after = Vec::new();
for r in runs {
match r.split(n) {
(Some(lhs), None) => {
before.push(lhs);
}
(Some(lhs), Some(rhs)) => {
before.push(lhs);
after.push(rhs);
}
(None, Some(rhs)) => {
after.push(rhs);
}
(None, None) => {}
}
n -= r.len();
}
(before, after)
}
fn apply_snap_runs(
origin: &Vec<Run>,
snap: &Vec<SnapRun>,
allocator: &mut Allocator,
) -> Result<Vec<Run>> {
let mut origin = origin.clone();
let mut runs = Vec::new();
for SnapRun(st, slen) in snap {
let (os, rest) = split_runs(*slen, &origin);
match st {
SnapRunType::Same => {
for o in os {
runs.push(o);
}
}
SnapRunType::Diff => {
for data in allocator.alloc(*slen)? {
runs.push(Run::Mapped {
data_begin: data.start,
len: data.end - data.start,
});
}
}
SnapRunType::Hole => {
runs.push(Run::UnMapped { len: *slen });
}
}
origin = rest;
}
Ok(runs)
}
// Snapshots share mappings, not neccessarily the entire ranges.
struct SnapS {
len: u64,
nr_snaps: u32,
// Snaps will differ from the origin by this percentage
percent_change: usize,
old_nr_data_blocks: u64,
new_nr_data_blocks: u64,
}
impl SnapS {
fn new(len: u64, nr_snaps: u32, percent_change: usize) -> Self {
let delta = len * (nr_snaps as u64) * (percent_change as u64) / 100;
let old_nr_data_blocks = len + 3 * delta;
let new_nr_data_blocks = len + 2 * delta;
SnapS {
len,
nr_snaps,
percent_change,
old_nr_data_blocks,
new_nr_data_blocks,
}
}
}
impl Scenario for SnapS {
fn generate_xml(&mut self, v: &mut dyn xml::MetadataVisitor) -> Result<()> {
let mut allocator = Allocator::new_shuffled(self.old_nr_data_blocks, 64..512);
let origin = mk_origin(0, self.len, &mut allocator)?;
v.superblock_b(&common_sb(self.old_nr_data_blocks))?;
origin.emit(v)?;
v.superblock_e()?;
Ok(())
}
fn get_new_nr_blocks(&self) -> u64 {
self.new_nr_data_blocks
}
}
#[test]
fn shrink_identical_snap() -> Result<()> {
let mut s = SnapS::new(1024, 1, 0);
test_shrink(&mut s)
}
//------------------------------------