Currently we only have a very brief explanation on the unexpected error
handling (only ASSERT()/WARN_ON()/BUG_ON()), and no further
recommendation on the proper usage of them.
This patch would improve the guideline by:
- Add btrfs_abort_transaction() usage
Which is the recommended way when possible.
- More detailed explanation on the usage of ASSERT()
Which is only a fail-fast option mostly designed for developers, thus
is only recommended to rule out some invalid function usage.
- More detailed explanation on the usage of WARN_ON()
Mostly for call sites which need a call trace strongly, and is not
applicable for a btrfs_abort_transaction() call.
- Completely discourage the usage of BUG_ON()
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
- use :file: and :command:
- simplify manual page references
- add more web links
- typo fixes
- more cross-references
Signed-off-by: David Sterba <dsterba@suse.com>
The remount workflow could cause some problems so make a note about it.
Recommend the umount/mount step by default. A seeding device used for
e.g. a root filesystem that gets updated and has snapshots is a real
world example where the space consumed by unreclaimed deleted snapshots
would hurt.
Pull-request: #462
Author: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
Other pages list the latest version first, do that here as well. Also
reorder index so the features are first before version changelogs.
Signed-off-by: David Sterba <dsterba@suse.com>
The links to repositories and contributors is hard to find as it's below
the feature list. Move it up as it is for overview.
Signed-off-by: David Sterba <dsterba@suse.com>
From the very beginning of free-space-tree feature, we allow mount
option "space_cache=v2" to convert the filesystem to the new feature.
But this is not the proper practice for new features (no matter if it's
incompat or compat_ro).
This is already making the clear_cache/space_cache mount option more
complex.
Thus this patch introduces the proper way to enable free-space-tree, and
I hope one day we can deprecate the "space_cache=" mount option.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When compiling the documents, we have the following warning:
~/btrfs-progs/Documentation/dev/On-disk-format.rst:369: WARNING: Bullet list ends without a blank line; unexpected unindent.
It's caused by a mismatched indent.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Rename the options so they more accurately reflect what the command is
actually doing. The feature is enabled/disabled in the end but it's not
a simple on/off like for others, the conversion takes time.
Signed-off-by: David Sterba <dsterba@suse.com>
There has been no update since 2014 and it's likely broken due to many
new features added to btrfs since then.
Signed-off-by: David Sterba <dsterba@suse.com>
- "Wipe" in storage terms is often understood as some kind of secure
deletion. Use "remove" instead in order to indicate that the space
cache is fully removed (and not just cleared and then e.g.
automatically rebuild).
- The --clear-space-cache option for btrfs check actually clears the
whole space cache, just as documented. Thus move any documentation
about the clear_cache mount option not doing so for v1 to that.
Instead, refer to the mount option.
- Also note that when clear_cache is used with v1, the free space cache
for block groups that are modified gets always cleared, but rebuilt
only if nospace_cache is not used.
Pull-request: #571
Signed-off-by: Christoph Anton Mitterer <mail@christoph.anton.mitterer.name>
Signed-off-by: David Sterba <dsterba@suse.com>
Clarify active vs. inactive swapfile regarding snapshotting and further minor
improvements.
Issue: #608
Pull-request: #618
Signed-off-by: Christoph Anton Mitterer <mail@christoph.anton.mitterer.name>
Signed-off-by: David Sterba <dsterba@suse.com>
The combination of --force and --repair was mistakenly documented as not
working on a mounted filesystem. Update help text, documentation and the
warning itself.
Issue: #503
Signed-off-by: David Sterba <dsterba@suse.com>
With previous btrfstune support to convert to block-group-tree, it has
implemented most of the infrastructure for bi-directional conversion.
This patch will implement the remaining conversion support to go back to
extent tree.
The modification includes:
- New convert_to_extent_tree() function in btrfstune.c
It's almost the same as convert_to_bg_tree(), but with small changes:
* No need to set extra features like NO_HOLES/FST.
* Need to delete the block group tree when everything finished.
- Update btrfs_delete_and_free_root() to handle non-global roots
Currently the function can only accepts global roots (extent/csum/free
space trees)
If we pass a non-global root into the function, we will screw up
global_roots_tree and crash.
Since we're going to use btrfs_delete_and_free_root() to free block
group tree which is not a global tree, this is needed.
- New handling for half converted fs in get_last_converted_bg()
There are two cases need to be handled:
* The bg tree is already empty
We need to grab the first bg in extent tree.
Or at conversion function we will fail at grabbing the first bg.
* The bg tree is not empty
Then we need to grab the last bg in extent tree.
- Extra root switching in involved functions. This involves:
* read_converting_block_groups()
* insert_block_group_item()
* update_block_group_item()
We just need to update our target root according to the current
compat_ro and super flags.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The feedback from the community on block group tree is very positive,
the only complain is, end users need to recompile btrfs-progs with
experimental features to enjoy the new feature.
So let's move it out of experimental features and let more people enjoy
faster mount speed.
Also change the option of btrfstune, from `-b` to
`--enable-block-group-tree` to avoid short option.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The option -R|--runtime-features was introduced to support features that
don't result in a full incompat flag change, thus things like
free-space-tree and quota features are put here.
But to end users, such separation of features is not helpful and can be
sometimes confusing.
Thus we're already migrating those runtime features into -O|--features
option under experimental builds.
I believe this is the proper time to move those runtime features into
-O|--features option, and mark the -R|--runtime-features option
deprecated.
For now we still keep the old option as for compatibility purposes.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
- convert "*" lists to "-" for newer releases, this is preferred in pull
requests
- update nested lists to the more compact layout (add more newlines,
un-indent)
- wrap overly long lines
Signed-off-by: David Sterba <dsterba@suse.com>
Use tabular format instead of the defintion list as it's more compact.
Enable syntax hilighting to code examples.
Signed-off-by: David Sterba <dsterba@suse.com>
The name of a mounted sub volume can not be found in /proc/self/mounts
but in /proc/self/mountinfo.
Pull-request: #596
Signed-off-by: Alexander Barton <alex@barton.de>
Signed-off-by: David Sterba <dsterba@suse.com>
