* **pure overwrite**: A write operation that does not require any
metadata or zeroing operations to perform during either submission
or completion.
- This implies that the fileystem must have already allocated space
+ This implies that the filesystem must have already allocated space
on disk as ``IOMAP_MAPPED`` and the filesystem must not place any
- constaints on IO alignment or size.
+ constraints on IO alignment or size.
The only constraints on I/O alignment are device level (minimum I/O
size and alignment, typically sector size).
* The **upper** level primitive is provided by the filesystem to
coordinate access to different iomap operations.
- The exact primitive is specifc to the filesystem and operation,
+ The exact primitive is specific to the filesystem and operation,
but is often a VFS inode, pagecache invalidation, or folio lock.
For example, a filesystem might take ``i_rwsem`` before calling
``iomap_file_buffered_write`` and ``iomap_file_unshare`` to prevent