Tom Lendacky 9087c37584 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 fafadcd165 ("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: fafadcd165 ("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>		2019-07-16 22:15:46 +02:00
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coherent.c	dma-mapping: remove the DMA_MEMORY_EXCLUSIVE flag	2019-02-20 07:27:00 -07:00
contiguous.c	dma-contiguous: use fallback alloc_pages for single pages	2019-06-03 16:00:07 +02:00
debug.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333	2019-06-05 17:37:06 +02:00
direct.c	dma-direct: Force unencrypted DMA under SME for certain DMA masks	2019-07-16 22:15:46 +02:00
dummy.c	dma-mapping: factor out dummy DMA ops	2018-12-13 21:06:12 +01:00
Kconfig	dma-direct: Force unencrypted DMA under SME for certain DMA masks	2019-07-16 22:15:46 +02:00
Makefile	dma-mapping: improve selection of dma_declare_coherent availability	2019-02-20 07:26:35 -07:00
mapping.c	dma-mapping: truncate dma masks to what dma_addr_t can hold	2019-06-25 07:54:06 +02:00
remap.c	dma-direct: handle DMA_ATTR_NO_KERNEL_MAPPING in common code	2019-06-25 14:28:05 +02:00
swiotlb.c	swiotlb: no need to check return value of debugfs_create functions	2019-07-03 16:57:18 +02:00
virt.c	dma-mapping: zero memory returned from dma_alloc_*	2018-12-20 08:13:52 +01:00