btrfs: move common NOCOW checks against a file extent into a helper

Browse source

Verifying if we can do a NOCOW write against a range fully or partially
covered by a file extent item requires verifying several constraints, and
these are currently duplicated at two different places: can_nocow_extent()
and run_delalloc_nocow().

This change moves those checks into a common helper function to avoid
duplication. It adds some comments and also preserves all existing
behaviour like for example can_nocow_extent() treating errors from the
calls to btrfs_cross_ref_exist() and csum_exist_in_range() as meaning
we can not NOCOW, instead of propagating the error back to the caller.
That specific behaviour is questionable but also reasonable to some
degree.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

...

This commit is contained in:

Filipe Manana 2022-03-30 15:31:06 +01:00 • committed by David Sterba

parent 395cb57e85

commit 619104ba45

1 changed files with 215 additions and 212 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

443

fs/btrfs/inode.c

View file