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| author |   Christoph Hellwig <hch@lst.de> | 2022-03-31 08:01:21 +0200 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2022-04-01 06:46:51 +0200 |
| commit | 4fe87e818ea492ade079cc01a31d088e445f8539 (patch) | |
| tree | 25a20702eebea21692e61ed758b287f2efa4267d /kernel/dma | |
| parent | PCI/doc: cleanup references to the legacy PCI DMA API (diff) | |
| download | linux-dev-4fe87e818ea492ade079cc01a31d088e445f8539.tar.xz linux-dev-4fe87e818ea492ade079cc01a31d088e445f8539.zip | |
dma-mapping: move pgprot_decrypted out of dma_pgprot
pgprot_decrypted is used by AMD SME systems to allow access to memory
that was set to not encrypted using set_memory_decrypted. That only
happens for dma-direct memory as the IOMMU solves the addressing
challenges for the encryption bit using its own remapping.
Move the pgprot_decrypted call out of dma_pgprot which is also used
by the IOMMU mappings and into dma-direct so that it is only used with
memory that was set decrypted.
Fixes: f5ff79fddf0e ("dma-mapping: remove CONFIG_DMA_REMAP")
Reported-by: Alex Xu (Hello71) <alex_y_xu@yahoo.ca>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Alex Xu (Hello71) <alex_y_xu@yahoo.ca>
Diffstat (limited to 'kernel/dma')
| -rw-r--r-- | kernel/dma/direct.c | 10 | ||||
| -rw-r--r-- | kernel/dma/mapping.c | 2 |
2 files changed, 8 insertions, 4 deletions
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 35a1d29d6a2e..9743c6ccce1a 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -277,12 +277,16 @@ void *dma_direct_alloc(struct device *dev, size_t size, } if (remap) { + pgprot_t prot = dma_pgprot(dev, PAGE_KERNEL, attrs); + + if (force_dma_unencrypted(dev)) + prot = pgprot_decrypted(prot); + /* remove any dirty cache lines on the kernel alias */ arch_dma_prep_coherent(page, size); /* create a coherent mapping */ - ret = dma_common_contiguous_remap(page, size, - dma_pgprot(dev, PAGE_KERNEL, attrs), + ret = dma_common_contiguous_remap(page, size, prot, __builtin_return_address(0)); if (!ret) goto out_free_pages; @@ -535,6 +539,8 @@ int dma_direct_mmap(struct device *dev, struct vm_area_struct *vma, int ret = -ENXIO; vma->vm_page_prot = dma_pgprot(dev, vma->vm_page_prot, attrs); + if (force_dma_unencrypted(dev)) + vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot); if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret)) return ret; diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index 559461a826ba..db7244291b74 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -407,8 +407,6 @@ EXPORT_SYMBOL(dma_get_sgtable_attrs); */ pgprot_t dma_pgprot(struct device *dev, pgprot_t prot, unsigned long attrs) { - if (force_dma_unencrypted(dev)) - prot = pgprot_decrypted(prot); if (dev_is_dma_coherent(dev)) return prot; #ifdef CONFIG_ARCH_HAS_DMA_WRITE_COMBINE |