[v2,0/7] Change fssum to support POSIX

Message

Arvind Raghavan June 21, 2020, 11:14 p.m. UTC

This patch series modifies fssum to be able to verify POSIX
fsync/fdatasync guarantees. In particular, it allows single
files/symlinks to be passed as input, which allows us to verify
an fsync on a single file without checking the entire directory.

It also adds an option for non-recursive directory traversal,
which is useful because POSIX fsync doesn't guarantee that all
subdirectories are synced. Finally, it adds a flag that allows
file size to be ignored (currently enabled by default). This is
useful because POSIX fsync of a directory doesn't guarantee that
the data in the children is persisted.

These changes will be followed up with several Crashmonkey [1]
tests which make use of these changes.

[1] https://github.com/utsaslab/crashmonkey

Changes since v1:
- Change readlink to readlinkat to fix bug
- Added helper sum_one function to simplify single file input
- Moved fstat -> fstatat change and both of the former into separate
  commit

Manually verified that all of the tests that use fssum still pass for
each commit:

tests/btrfs/083
tests/btrfs/050
tests/btrfs/007
tests/btrfs/016
tests/btrfs/128
tests/btrfs/040
tests/btrfs/092
tests/btrfs/087
tests/btrfs/039
tests/btrfs/127
tests/btrfs/044
tests/btrfs/144
tests/btrfs/168
tests/btrfs/134
tests/btrfs/045
tests/btrfs/129
tests/btrfs/043
tests/btrfs/145
tests/btrfs/191
tests/btrfs/147
tests/btrfs/030
tests/btrfs/077
tests/btrfs/155
tests/btrfs/133
tests/btrfs/038
tests/btrfs/053
tests/btrfs/189
tests/btrfs/084
tests/btrfs/135
tests/btrfs/200
tests/btrfs/178
tests/btrfs/051
tests/generic/474
tests/generic/547

Arvind Raghavan (7):
  src/fssum: Make sum_file_data global
  src/fssum: Refactoring changes for recursive traversal
  src/fssum: Refactor recursive traversal
  src/fssum: Add flag -R for non-recursive mode
  src/fssum: Add a flag for including file size in checksum
  src/fssum: Allow single file input
  src/fssum: Fix whitespace in usage

 src/fssum.c | 354 ++++++++++++++++++++++++++++++----------------------
 1 file changed, 203 insertions(+), 151 deletions(-)