On 2021/9/30 18:03, Filipe Manana wrote:

On Thu, Sep 30, 2021 at 1:06 AM Qu Wenruo [off-list ref] wrote:

quoted

The new test case will create two send streams:

- parent_stream
   A full send stream.
   Contains one file, as clone source.

- clone_stream
   An incremental send stream.
   Contains one clone operation.

Then we will receive the parent_stream with default mount options, while
try to receive the clone_stream with nodatasum mount option.

This should result clone failure due to nodatasum flag mismatch.

Then check if the receive can continue with --clone-fallback option.

Signed-off-by: Qu Wenruo <redacted>
---
  .../049-receive-clone-fallback/test.sh        | 60 +++++++++++++++++++
  1 file changed, 60 insertions(+)
  create mode 100755 tests/misc-tests/049-receive-clone-fallback/test.sh

diff --git a/tests/misc-tests/049-receive-clone-fallback/test.sh b/tests/misc-tests/049-receive-clone-fallback/test.sh
new file mode 100755
index 000000000000..d383c0e08a68
--- /dev/null
+++ b/tests/misc-tests/049-receive-clone-fallback/test.sh

@@ -0,0 +1,60 @@
+#!/bin/bash
+# Verify that btrfs receive can fallback to buffered copy when clone
+# failed
+
+source "$TEST_TOP/common"
+
+check_prereq mkfs.btrfs
+check_prereq btrfs
+setup_root_helper
+prepare_test_dev
+
+tmp=$(mktemp -d --tmpdir btrfs-progs-send-stream.XXXXXX)
+
+# Create two send stream, one as the parent and the other as an incremental

stream -> streams

quoted

+# stream with one clone operation.
+run_check_mkfs_test_dev
+run_check_mount_test_dev -o datacow,datasum
+run_check $SUDO_HELPER "$TOP/btrfs" subvolume create "$TEST_MNT/subv"

You can use the default subvolume and therefore avoid creating a
subvolume and making the test longer than needed.
Your call.

I understand we can use the default fs tree, but I just can't find my
mind at peace when doing snapshoting of fs tree.

It always remind me of the bad memories using hacky way to solve the
qgroup problem for such snapshot.

Thus I always try to avoid snapshotting fs tree.

quoted

+run_check $SUDO_HELPER dd if=/dev/zero bs=1M count=1 of="$TEST_MNT/subv/file1"
+run_check $SUDO_HELPER "$TOP/btrfs" subvolume snapshot -r "$TEST_MNT/subv" \
+       "$TEST_MNT/snap1"
+run_check $SUDO_HELPER cp --reflink=always "$TEST_MNT/subv/file1" \
+       "$TEST_MNT/subv/file2"
+run_check $SUDO_HELPER "$TOP/btrfs" subvolume snapshot -r "$TEST_MNT/subv" \
+       "$TEST_MNT/snap2"
+
+run_check $SUDO_HELPER "$TOP/btrfs" send -f "$tmp/parent_stream" \
+       "$TEST_MNT/snap1"
+run_check $SUDO_HELPER "$TOP/btrfs" send -f "$tmp/clone_stream" \
+       -p "$TEST_MNT/snap1" "$TEST_MNT/snap2"
+
+run_check_umount_test_dev
+run_check_mkfs_test_dev
+
+# Now we have the needed stream, try to receive them with different mount

Reading this is confusing, it mentions receiving them with different
mount options, but they are the same for the first receive.

quoted

+# options
+run_check_mount_test_dev -o datacow -o datasum
+
+# Receiving the full stream should not fail
+run_check $SUDO_HELPER "$TOP/btrfs" receive -f "$tmp/parent_stream" "$TEST_MNT"
+
+# No remount helper, so here we manually unmoutn and re-mount with different
+# nodatasum option

Seems pointless to mention there's a lack of a remount helper in the
test framework.
Just say that now we mount the filesystem with nodatasum so that the
new file received through the incremental stream ends up with the
nodatasum flag set.

Or maybe I should just add run_check_remount_test().

Thanks for the review,
Qu

Thanks.

quoted

+run_check_umount_test_dev
+run_check_mount_test_dev -o datacow,nodatasum
+
+# Receiving incremental send stream without --clone-fallback should fail.
+# As the clone source and destination have different NODATASUM flags
+run_mustfail "receiving clone with different NODATASUM should fail" \
+       $SUDO_HELPER "$TOP/btrfs" receive -f "$tmp/clone_stream" "$TEST_MNT"
+
+# Firstly we need to cleanup the partially received subvolume
+run_check $SUDO_HELPER "$TOP/btrfs" subvolume delete "$TEST_MNT/snap2"
+
+# With --clone-fallback specified, the receive should finish without problem
+run_check $SUDO_HELPER "$TOP/btrfs" receive --clone-fallback \
+       -f "$tmp/clone_stream" "$TEST_MNT"
+run_check_umount_test_dev
+
+rm -rf -- "$tmp"
--
2.33.0