Stop proactively relocate blocks during migrations, this can cause a number of
failure states such: clobbering the v1 superblock if we relocate root, and
invalidating directory pointers if we relocate the head of a directory. On top
of this, relocations increase the overall complexity of lfs_migration, which is
already a delicate operation.
The superblock entry takes up id 0 in the root directory (not all
entries are files, though currently the superblock is the only
exception). Normally, reading a directory correctly skips the
superblock and only reports non-superblock files.
However, this doesn't work perfectly for lfs_dir_seek, which tries
to be clever to not touch the disk.
Fortunately, we can fix this by adding an offset for the superblock.
This will only work while the superblock is the only non-file entry,
otherwise we would need to touch the disk to properly seek in a
directory (though we already touch the disk a bit to get dir-tails
during seeks).
Found by jhartika
To ensure 16 bit devices do not invalidly truncate lfs_file_write return codes, change
the return variable to be lfs_ssize_t which is the lfs_file_write return code and
cast to int if it is a negative error code.
lfs_dir_find returns either a negative return code or a tag.
For 32 bit machines with int as 32 bits this co-incides, but for smaller
bit processors, we need to ensure a 32 bit value is returned so change
the return type to lfs_stag_t.
Build warnings exist on a gcc based 16 bit compiler. Cast relevant types
to fix.
littlefs/lfs.c: In function 'lfs_gstate_xororphans':
littlefs/lfs.c:355:5: warning: left shift count >= width of type
littlefs/lfs.c: In function 'lfs_dir_fetchmatch':
littlefs/lfs.c:849:17: warning: left shift count >= width of type
littlefs/lfs.c: In function 'lfs_dir_commitcrc':
littlefs/lfs.c:1278:9: warning: left shift count >= width of type
This is a result of feedback that the current release notes made it too
difficult to see what changes happened on patch releases. From my
experience as well it became difficult to chase down which release a
commit landed on.
The risk is that this creates additional noise, both for the release
page and for user notifications. I am open to feedback if this causes a
problem.
Other tweaks on the CI side, these came from iteration with the same
scheme for coru and equeue:
- Changed version branch updates to be atomic (vN and vN-prefix). This
makes it a bit easier to fix if one of the pushes fails due to a rogue
branch with the same name.
- Added GEKY_BOT_DRAFT as a CI macro that can optionally switch between
only creating drafts or immediately posting a release. The default is
what I will be trying with littlefs which is to draft minor/major
releases, but automatically create patch release.
The real benefit of automatic releases is to use on tiny repos that
don't really have an active maintainer. Though this is definitely no
longer the case with littlefs, and I'm happy it has gained this much
attention.
When using lfs_file_truncate() to make a file shorter the file block and
off were incorrectly positioned at the new end, resulting in invalid
data accessed when reading. Lift the seek pointer restoration to apply
to both increasing and reducing truncates.
Signed-off-by: Peter A. Bigot <pab@pabigot.com>
The difference between 0xffffffff and 0xfffffffe is too subtle. Use
names that reflect what the value represents.
Signed-off-by: Peter A. Bigot <pab@pabigot.com>
Found during testing, the issue was with lfs_migrate in combination with
wear leveling.
Normally, we can expect lfs_migrate to be able to respect the user-configured
block_cycles. It already has allocation information on which blocks are
used by both v1 and v2, so it should be safe to relocate blocks as
needed.
However, this fell apart when root was relocated. If lfs_migrate found a
root that needed migration, it would happily relocate the root. This
would normally be fine, except relocating the root has a side-effect of
needed to update the superblock. Which, during migration, is in a
delicate state of containing both v1's and v2's superblocks in the same
metadata pair. If the superblock ends up needing to compact, this would
clobber the v1 superblock and corrupt the filesystem during migration.
The best fix I could come up with is to specifically dissallow migrating the
root directory during migration. Fortunately this is behind the
LFS_MIGRATE macro, so the code cost for this check is not normally paid.
Due to the logging nature of metadata pairs, switching from inline files
(type3 = 0x201) to CTZ skip-lists (type3 = 0x202) does not explicitly
erase inline files, but instead leaves them up to compaction to omit.
To save code size, this is handled by the same logic that deduplicates
tags.
Unfortunately, this wasn't working. Due to a relatively late change in v2
the struct's type field was changed to no longer be a part of determining a
tag's "uniqueness". A part of this should have been the modification of
directory traversal filtering to respect type-dependent uniqueness, but
I missed this.
The fix is to add in correct type-dependent filtering. Also there was
some clean up necessary around removing delete tags during compaction
and outlining files.
Note that while this appears to conflict with the possibility of
combining inline + ctz files, we still have the device-side-only
LFS_TYPE_FROM tag that can be repurposed for 256 additional inline
"chunks".
Found by Johnxjj
Previously these returned LFS_ERR_BADF. But attempting to modify a file
opened read-only, or reading a write-only flie, is a user error and
should not occur in normal use.
Changing this to an assert allows the logic to be omitted if the user
disables asserts to reduce the code footprint (not suggested unless the
user really really knows what they're doing).
This is a minor quality of life change to help debugging, specifically
when debugging test failures.
Before, the test framework used hex, while the log output used decimal.
This was slightly annoying to convert between.
Why not output lengths/offset in hex? I don't have a big reason. I find
it easier to reason about lengths in decimal and ids (such as addresses
or block numbers) in hex. But this may just be me.
