Merge patch series "iomap: buffered io changes"

This series contains several fixes and cleanups:

* Renaming bytes_pending/bytes_accounted to
  bytes_submitted/bytes_not_submitted for improved code clarity

* Accounting for unaligned end offsets when truncating read ranges

* Adding documentation for iomap_finish_folio_write() requirements

* Optimizing pending async writeback accounting logic

* Simplifying error handling in ->read_folio_range() for read operations

* Streamlining logic for skipping reads during write operations

* Replacing manual bitmap scanning with find_next_bit() for both dirty
  and uptodate bitmaps, improving performance

* patches from https://patch.msgid.link/20251111193658.3495942-1-joannelkoong@gmail.com:
  iomap: use find_next_bit() for uptodate bitmap scanning
  iomap: use find_next_bit() for dirty bitmap scanning
  iomap: simplify when reads can be skipped for writes
  iomap: simplify ->read_folio_range() error handling for reads
  iomap: optimize pending async writeback accounting
  docs: document iomap writeback's iomap_finish_folio_write() requirement
  iomap: account for unaligned end offsets when truncating read range
  iomap: rename bytes_pending/bytes_accounted to bytes_submitted/bytes_not_submitted

Link: https://patch.msgid.link/20251111193658.3495942-1-joannelkoong@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>