Commit Graph

13 Commits

Author SHA1 Message Date
Christoph Hellwig
e89f5b3701 dma-mapping: Don't clear GFP_ZERO in dma_alloc_attrs
Revert the clearing of __GFP_ZERO in dma_alloc_attrs and move it to
dma_direct_alloc for now.  While most common architectures always zero dma
cohereny allocations (and x86 did so since day one) this is not documented
and at least arc and s390 do not zero without the explicit __GFP_ZERO
argument.

Fixes: 57bf5a8963 ("dma-mapping: clear harmful GFP_* flags in common code")
Reported-by: Evgeniy Didin <Evgeniy.Didin@synopsys.com>
Reported-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Evgeniy Didin <Evgeniy.Didin@synopsys.com>
Cc: iommu@lists.linux-foundation.org
Link: https://lkml.kernel.org/r/20180328133535.17302-2-hch@lst.de
2018-03-28 17:34:23 +02:00
Christoph Hellwig
c10f07aa27 dma/direct: Handle force decryption for DMA coherent buffers in common code
With that in place the generic DMA-direct routines can be used to
allocate non-encrypted bounce buffers, and the x86 SEV case can use
the generic swiotlb ops including nice features such as using CMA
allocations.

Note that I'm not too happy about using sev_active() in DMA-direct, but
I couldn't come up with a good enough name for a wrapper to make it
worth adding.

Tested-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Jon Mason <jdmason@kudzu.us>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Muli Ben-Yehuda <mulix@mulix.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: iommu@lists.linux-foundation.org
Link: http://lkml.kernel.org/r/20180319103826.12853-14-hch@lst.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-20 10:01:59 +01:00
Christoph Hellwig
42ed64524d dma-direct: comment the dma_direct_free calling convention
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-02-12 15:59:07 +00:00
Christoph Hellwig
f25e6f6b4e dma-direct: mark as is_phys
Various PCI_DMA_BUS_IS_PHYS implementations rely on this flag to make proper
decisions for block and networking addressability.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-02-12 15:59:06 +00:00
Christoph Hellwig
1a9777a8a0 dma-direct: reject too small dma masks
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2018-01-15 09:35:15 +01:00
Christoph Hellwig
19dca8c0ef dma-direct: make dma_direct_{alloc,free} available to other implementations
So that they don't need to indirect through the operation vector.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>
2018-01-15 09:35:14 +01:00
Christoph Hellwig
95f183916d dma-direct: retry allocations using GFP_DMA for small masks
If an attempt to allocate memory succeeded, but isn't inside the
supported DMA mask, retry the allocation with GFP_DMA set as a
last resort.

Based on the x86 code, but an off by one error in what is now
dma_coherent_ok has been fixed vs the x86 code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-15 09:35:13 +01:00
Christoph Hellwig
c61e963734 dma-direct: add support for allocation from ZONE_DMA and ZONE_DMA32
This allows to dip into zones for lower memory if they are available.
If one of the zones is not available the corresponding GFP_* flag
will evaluate to 0 so they won't change anything.  We provide an
arch tunable for those architectures that do not use GFP_DMA for
the lowest 24-bits, given that there are a few.

Roughly based on the x86 code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-15 09:35:12 +01:00
Christoph Hellwig
21f237e4d0 dma-direct: use node local allocations for coherent memory
To preserve the x86 behavior.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2018-01-15 09:35:11 +01:00
Christoph Hellwig
080321d3b3 dma-direct: add support for CMA allocation
Try the CMA allocator for coherent allocations if supported.

Roughly modelled after the x86 code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-15 09:35:09 +01:00
Christoph Hellwig
2797596992 dma-direct: add dma address sanity checks
Roughly based on the x86 pci-nommu implementation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-15 09:35:08 +01:00
Christoph Hellwig
2e86a04780 dma-direct: use phys_to_dma
This means it uses whatever linear remapping scheme that the architecture
provides is used in the generic dma_direct ops.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>
2018-01-15 09:35:07 +01:00
Christoph Hellwig
002e67454f dma-direct: rename dma_noop to dma_direct
The trivial direct mapping implementation already does a virtual to
physical translation which isn't strictly a noop, and will soon learn
to do non-direct but linear physical to dma translations through the
device offset and a few small tricks.  Rename it to a better fitting
name.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>
2018-01-15 09:35:06 +01:00