We already zero the memory after allocating it from the pool that
this function fills, and having the memset here in this form means
we can't support CMA highmem allocations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Russell King - ARM Linux <linux@armlinux.org.uk>
Commit bfd56cd605 ("dma-mapping: support highmem in the generic remap
allocator") replaced dma_direct_alloc_pages() with __dma_direct_alloc_pages(),
which doesn't set dma_handle and zero allocated memory. Fix it by doing this
directly in the caller function.
Fixes: bfd56cd605 ("dma-mapping: support highmem in the generic remap allocator")
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Do not waste vmalloc space on allocations that do not require a mapping
into the kernel address space.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
By using __dma_direct_alloc_pages we can deal entirely with struct page
instead of having to derive a kernel virtual address.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
The arm64 codebase to implement coherent dma allocation for architectures
with non-coherent DMA is a good start for a generic implementation, given
that is uses the generic remap helpers, provides the atomic pool for
allocations that can't sleep and still is realtively simple and well
tested. Move it to kernel/dma and allow architectures to opt into it
using a config symbol. Architectures just need to provide a new
arch_dma_prep_coherent helper to writeback an invalidate the caches
for any memory that gets remapped for uncached access.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
The dma remap code only makes sense for not cache coherent architectures
(or possibly the corner case of highmem CMA allocations) and currently
is only used by arm, arm64, csky and xtensa. Split it out into a
separate file with a separate Kconfig symbol, which gets the right
copyright notice given that this code was written by Laura Abbott
working for Code Aurora at that point.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Laura Abbott <labbott@redhat.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
