The free space tree is a better way to track the free space and has been
tested in the wild for a long time. The backward compatibility is
sufficient, several long term kernels. On-line conversion from v1 to v2
can be done by mount, switching from v2 to v1 can be done by 'btrfs
check'.
Issue: #295
Signed-off-by: David Sterba <dsterba@suse.com>
The no-holes feature reduces consumption of metadata by not representing
file holes. Reducing metadata is a good thing in general, this is the
main goal to enable this by default.
There's a drawback, related to the missing information about holes. The
'check' tool cannot use it to cross-reference extent information and in
some cases may not be able to detect a problem.
The no-hole feature can be also enabled by 'btrfstune -n' on an
unmounted filesystem.
Issue: #405
Signed-off-by: David Sterba <dsterba@suse.com>
With the zoned feature enabled, a zoned block device-aware btrfs
allocates block groups aligned to the device zones and always written in
sequential zones at the zone write pointer position.
It also supports "emulated" zoned mode on a non-zoned device. In the
emulated mode, btrfs emulates conventional zones by slicing the device
into fixed-size zones.
We don't support conversion from the ext4 volume with the zoned feature
because we can't be sure all the converted block groups are aligned to
zone boundaries.
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are several problems for current sectorsize check:
- No check at all for sectorsize
This means you can even specify "-s 62k".
- No way to specify sectorsize smaller than page size
Fix all these problems by:
- Introduce btrfs_check_sectorsize()
To do:
* power of 2 check for sectorsize
* lower and upper boundary check for sectorsize
* warn about sectorsize mismatch with page size
- Remove the max() between page size and sectorsize
This allows us to override the sectorsize for 64K page systems.
- Make nodesize calculation based on sectorsize
No need to use page size any more.
Users who specify sectorsize manually really know what they are doing,
and we have warned them already.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add a runtime feature (-R) flag for the free space tree. A filesystem
that is mkfs'd with -R free-space-tree then mounted with no options has
the same contents as one mkfs'd without the option, then mounted with
'-o space_cache=v2'.
The only tricky thing is in exactly how to call the tree creation code.
Using btrfs_create_free_space_tree as is did not quite work, because an
extra reference to the eb (root->commit_root) is leaked, which mkfs
complains about with a warning. I opted to follow how the uuid tree is
created by adding it to the dirty roots list for cleanup by
commit_tree_roots in commit_transaction. As a result,
btrfs_create_free_space_tree no longer exactly matches the version in
the kernel sources.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
Add support for enabling quotas at mkfs time. The qgroup accounting will
be consistent, ie. works with --rootdir.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Make the features structures more generic to allow mkfs-time and
mount-time sets to be defined.
This provides base for later mkfs support of mount-time features like
quotas.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba
Naohiro Aota
Qu Wenruo
Boris Burkov