Some IOMMUs allocate memory areas spanning LLD's segment boundary limit. It
forces low level drivers to have a workaround to adjust scatter lists that the
IOMMU builds. We are in the process of making all the IOMMUs respect the
segment boundary limits to remove such work around in LLDs.
SPARC64 IOMMUs were rewritten to use the IOMMU helper functions and the commit
89c94f2f70 made the IOMMUs not allocate memory
areas spanning the segment boundary limit.
However, SPARC64 IOMMUs allocate memory areas first then try to merge them
(while some IOMMUs walk through all the sg entries to see how they can be
merged first and allocate memory areas). So SPARC64 IOMMUs also need the
boundary limit checking when they try to merge sg entries.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Mimicks almost perfectly the powerpc IOMMU code, except that it
doesn't have the IOMMU_PAGE_SIZE != PAGE_SIZE handling, and it also
lacks the device dma mask support bits.
I'll add that later as time permits, but this gets us at least back to
where we were beforehand.
Signed-off-by: David S. Miller <davem@davemloft.net>
Changeset fde6a3c82d ("iommu sg merging:
sparc64: make iommu respect the segment size limits") broke sparc64
because whilst it added the segment limiting code to the first pass of
SG mapping (in prepare_sg()) it did not add matching code to the
second pass handling (in fill_sg())
As a result the two passes disagree where the segment boundaries
should be, resulting in OOPSes, DMA corruption, and corrupted
superblocks.
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 2c941a2040 looks incomplete. The
helper functions like prepare_sg() need to support sg chaining too.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This updates the sparc64 iommu/pci dma mappers to sg chaining.
Acked-by: David S. Miller <davem@davemloft.net>
Later updated to newer kernel with unified sparc64 iommu sg handling.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Fully unify all of the DMA ops so that subordinate bus types to
the DMA operation providers (such as ebus, isa, of_device) can
work transparently.
Basically, we just make sure that for every system device we
create, the dev->archdata 'iommu' and 'stc' fields are filled
in.
Then we have two platform variants of the DMA ops, one for SUN4U which
actually programs the real hardware, and one for SUN4V which makes
hypervisor calls.
This also fixes the crashes in parport_pc on sparc64, reported by
Meelis Roos.
Signed-off-by: David S. Miller <davem@davemloft.net>
