[PATCHv4 0/2] dm: finer grained memory alignment

[Keith Busch <kbusch@meta.com>]

From: Keith Busch <kbusch@kernel.org>

This is the updated series for allowing arbitrary memory alignment,
enabling direct-io without bounce buffers for dm-crypt.

The previous version was posted here:

  https://lore.kernel.org/dm-devel/20260114154954.3282207-2-kbusch@meta.com/

And is based on the current dm-7.1 branch, which has the necessary
dm-integrity updates that make patch 1 a no-op.

Changes from v3:

 * Split off the generic dm-table queue limits update into its own prep
   patch.

 * Squashed the rest into a single patch just so it doesn't introduce a
   temporary commit point where the reported limits can't always be
   executed.

 * Do not report a dma_alignment lower than the backing device's; this
   is necessary as the incoming buffers are used directly for READ
   rather than bounced like WRITE. 

 * Fallback to a mempool if we can't allocate the scatterlist with
   kmalloc and updated gfp_t flags accordingly.

 * Various cleanups.

Keith Busch (2):
  dm: initialize dma_alignment to 0
  dm-crypt: allow unaligned bio_vecs for direct io

 drivers/md/dm-crypt.c | 147 ++++++++++++++++++++++++++++++++++++------
 drivers/md/dm-table.c |   1 +
 2 files changed, 128 insertions(+), 20 deletions(-)

-- 
2.52.0