dma: swiotlb: track pool encryption state and honor DMA_ATTR_CC_SHARED

Browse source

Teach swiotlb to distinguish between encrypted and decrypted bounce
buffer pools, and make allocation and mapping paths select a pool whose
state matches the requested DMA attributes.

Add a cc_shared flag to io_tlb_mem, initialize it for the default and
restricted pools, and propagate __DMA_ATTR_ALLOC_CC_SHARED into swiotlb
pool allocation. Reject swiotlb alloc/map requests when the selected pool
does not match the required encrypted/decrypted state.

Also return DMA addresses with the matching phys_to_dma_{encrypted,
unencrypted} helper so the DMA address encoding stays consistent with the
chosen pool.

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Jiri Pirko <jiri@nvidia.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Mostafa Saleh <smostafa@google.com>
Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>
Link: https://lore.kernel.org/r/20260717180442.110954-14-aneesh.kumar@kernel.org
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>

...

This commit is contained in:

Aneesh Kumar K.V (Arm) 2026-07-17 23:34:31 +05:30 • committed by Marek Szyprowski

parent 7fcad5e371

commit d5fd03cdd6

4 changed files with 162 additions and 48 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

10

include/linux/dma-direct.h

View file

10

include/linux/swiotlb.h

View file

13

kernel/dma/direct.c

View file

177

kernel/dma/swiotlb.c

View file