Try to mitigate potential future driver core api changes by adding a
padding to struct dma_map_ops.
Based on a change made to the RHEL/CENTOS 8 kernel.
Bug: 151154716
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: Icbec584dee3716f341a7831a4810025f690eab4a
Non-coherent devices on systems that support a system or
last level cache may want to request that allocations be
cached in the system cache. For memory that is allocated
by the kernel, and used for DMA with devices, the memory
attributes used for CPU access should match the memory
attributes that will be used for device access.
The memory attributes that need to be programmed into
the MAIR for system cache usage are:
0xf4 - Normal memory, outer write back read/write allocate,
inner non-cacheable.
There is currently no support for this memory attribute for
CPU mappings, so add it.
Bug: 176778547
Change-Id: I3abc7becd408f20ac5499cbbe3c6c6f53f784107
Signed-off-by: Isaac J. Manjarres <isaacm@codeaurora.org>
Due to a mismerge a bunch of prototypes that should have moved to
dma-map-ops.h are still in dma-mapping.h, fix that up.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Use and entirely separate code path for the DMA_ATTR_NO_KERNEL_MAPPING
path. This avoids any confusion about the ret type, and avoids lots of
attr checks and helpers that can be significantly simplified now.
It also ensures that common handling is applied to architetures still
using the arch alloc/free hooks.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Most of dma-debug.h is not required by anything outside of kernel/dma.
Move the four declarations needed by dma-mappin.h or dma-ops providers
into dma-mapping.h and dma-map-ops.h, and move the remainder of the
file to kernel/dma/debug.h.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Merge dma-contiguous.h into dma-map-ops.h, after removing the comment
describing the contiguous allocator into kernel/dma/contigous.c.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Split out all the bits that are purely for dma_map_ops implementations
and related code into a new <linux/dma-map-ops.h> header so that they
don't get pulled into all the drivers. That also means the architecture
specific <asm/dma-mapping.h> is not pulled in by <linux/dma-mapping.h>
any more, which leads to a missing includes that were pulled in by the
x86 or arm versions in a few not overly portable drivers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
