Viewing file:  dma-direct.h (3.62 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Internals of the DMA direct mapping implementation. Only for use by the
* DMA mapping code and IOMMU drivers.
*/
#ifndef _LINUX_DMA_DIRECT_H
#define _LINUX_DMA_DIRECT_H 1
#include <linux/dma-mapping.h>
#include <linux/dma-map-ops.h>
#include <linux/memblock.h> /* for min_low_pfn */
#include <linux/mem_encrypt.h>
#include <linux/swiotlb.h>
extern unsigned int zone_dma_bits;
/*
* Record the mapping of CPU physical to DMA addresses for a given region.
*/
struct bus_dma_region {
phys_addr_t cpu_start;
dma_addr_t dma_start;
u64 size;
};
static inline dma_addr_t translate_phys_to_dma(struct device *dev,
phys_addr_t paddr)
{
const struct bus_dma_region *m;
for (m = dev->dma_range_map; m->size; m++) {
u64 offset = paddr - m->cpu_start;
if (paddr >= m->cpu_start && offset < m->size)
return m->dma_start + offset;
}
/* make sure dma_capable fails when no translation is available */
return DMA_MAPPING_ERROR;
}
static inline phys_addr_t translate_dma_to_phys(struct device *dev,
dma_addr_t dma_addr)
{
const struct bus_dma_region *m;
for (m = dev->dma_range_map; m->size; m++) {
u64 offset = dma_addr - m->dma_start;
if (dma_addr >= m->dma_start && offset < m->size)
return m->cpu_start + offset;
}
return (phys_addr_t)-1;
}
#ifdef CONFIG_ARCH_HAS_PHYS_TO_DMA
#include <asm/dma-direct.h>
#ifndef phys_to_dma_unencrypted
#define phys_to_dma_unencrypted phys_to_dma
#endif
#else
static inline dma_addr_t phys_to_dma_unencrypted(struct device *dev,
phys_addr_t paddr)
{
if (dev->dma_range_map)
return translate_phys_to_dma(dev, paddr);
return paddr;
}
/*
* If memory encryption is supported, phys_to_dma will set the memory encryption
* bit in the DMA address, and dma_to_phys will clear it.
* phys_to_dma_unencrypted is for use on special unencrypted memory like swiotlb
* buffers.
*/
static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
{
return __sme_set(phys_to_dma_unencrypted(dev, paddr));
}
static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dma_addr)
{
phys_addr_t paddr;
if (dev->dma_range_map)
paddr = translate_dma_to_phys(dev, dma_addr);
else
paddr = dma_addr;
return __sme_clr(paddr);
}
#endif /* !CONFIG_ARCH_HAS_PHYS_TO_DMA */
#ifdef CONFIG_ARCH_HAS_FORCE_DMA_UNENCRYPTED
bool force_dma_unencrypted(struct device *dev);
#else
static inline bool force_dma_unencrypted(struct device *dev)
{
return false;
}
#endif /* CONFIG_ARCH_HAS_FORCE_DMA_UNENCRYPTED */
static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size,
bool is_ram)
{
dma_addr_t end = addr + size - 1;
if (addr == DMA_MAPPING_ERROR)
return false;
if (is_ram && !IS_ENABLED(CONFIG_ARCH_DMA_ADDR_T_64BIT) &&
min(addr, end) < phys_to_dma(dev, PFN_PHYS(min_low_pfn)))
return false;
return end <= min_not_zero(*dev->dma_mask, dev->bus_dma_limit);
}
u64 dma_direct_get_required_mask(struct device *dev);
void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
gfp_t gfp, unsigned long attrs);
void dma_direct_free(struct device *dev, size_t size, void *cpu_addr,
dma_addr_t dma_addr, unsigned long attrs);
struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp);
void dma_direct_free_pages(struct device *dev, size_t size,
struct page *page, dma_addr_t dma_addr,
enum dma_data_direction dir);
int dma_direct_supported(struct device *dev, u64 mask);
dma_addr_t dma_direct_map_resource(struct device *dev, phys_addr_t paddr,
size_t size, enum dma_data_direction dir, unsigned long attrs);
#endif /* _LINUX_DMA_DIRECT_H */
|