kernel_optimize_test/include/linux/dma-direct.h

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/* 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;
u64 offset;
};
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++)
if (paddr >= m->cpu_start && paddr - m->cpu_start < m->size)
return (dma_addr_t)paddr - m->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++)
if (dma_addr >= m->dma_start && dma_addr - m->dma_start < m->size)
return (phys_addr_t)dma_addr + m->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 */
dma-direct: Force unencrypted DMA under SME for certain DMA masks If a device doesn't support DMA to a physical address that includes the encryption bit (currently bit 47, so 48-bit DMA), then the DMA must occur to unencrypted memory. SWIOTLB is used to satisfy that requirement if an IOMMU is not active (enabled or configured in passthrough mode). However, commit fafadcd16595 ("swiotlb: don't dip into swiotlb pool for coherent allocations") modified the coherent allocation support in SWIOTLB to use the DMA direct coherent allocation support. When an IOMMU is not active, this resulted in dma_alloc_coherent() failing for devices that didn't support DMA addresses that included the encryption bit. Addressing this requires changes to the force_dma_unencrypted() function in kernel/dma/direct.c. Since the function is now non-trivial and SME/SEV specific, update the DMA direct support to add an arch override for the force_dma_unencrypted() function. The arch override is selected when CONFIG_AMD_MEM_ENCRYPT is set. The arch override function resides in the arch/x86/mm/mem_encrypt.c file and forces unencrypted DMA when either SEV is active or SME is active and the device does not support DMA to physical addresses that include the encryption bit. Fixes: fafadcd16595 ("swiotlb: don't dip into swiotlb pool for coherent allocations") Suggested-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> [hch: moved the force_dma_unencrypted declaration to dma-mapping.h, fold the s390 fix from Halil Pasic] Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-07-11 03:01:19 +08:00
#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 */