linux_dsm_epyc7002/arch/ia64/kernel/dma-mapping.c
Christoph Hellwig 34dc0ea6bc dma-direct: provide mmap and get_sgtable method overrides
For dma-direct we know that the DMA address is an encoding of the
physical address that we can trivially decode.  Use that fact to
provide implementations that do not need the arch_dma_coherent_to_pfn
architecture hook.  Note that we still can only support mmap of
non-coherent memory only if the architecture provides a way to set an
uncached bit in the page tables.  This must be true for architectures
that use the generic remap helpers, but other architectures can also
manually select it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
2019-11-11 10:52:15 +01:00

22 lines
607 B
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/dma-direct.h>
#include <linux/export.h>
/* Set this to 1 if there is a HW IOMMU in the system */
int iommu_detected __read_mostly;
const struct dma_map_ops *dma_ops;
EXPORT_SYMBOL(dma_ops);
void *arch_dma_alloc(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
{
return dma_direct_alloc_pages(dev, size, dma_handle, gfp, attrs);
}
void arch_dma_free(struct device *dev, size_t size, void *cpu_addr,
dma_addr_t dma_addr, unsigned long attrs)
{
dma_direct_free_pages(dev, size, cpu_addr, dma_addr, attrs);
}