summaryrefslogtreecommitdiffstats
path: root/arch/x86
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2019-07-20 12:09:52 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-07-20 12:09:52 -0700
commitac60602a6d8f6830dee89f4b87ee005f62eb7171 (patch)
treeea8810e0d7abc82755c8db00904015ecbf99a8b4 /arch/x86
parentc6dd78fcb8eefa15dd861889e0f59d301cb5230c (diff)
parent449fa54d6815be8c2c1f68fa9dbbae9384a7c03e (diff)
downloadlinux-ac60602a6d8f6830dee89f4b87ee005f62eb7171.tar.bz2
Merge tag 'dma-mapping-5.3-1' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping fixes from Christoph Hellwig: "Fix various regressions: - force unencrypted dma-coherent buffers if encryption bit can't fit into the dma coherent mask (Tom Lendacky) - avoid limiting request size if swiotlb is not used (me) - fix swiotlb handling in dma_direct_sync_sg_for_cpu/device (Fugang Duan)" * tag 'dma-mapping-5.3-1' of git://git.infradead.org/users/hch/dma-mapping: dma-direct: correct the physical addr in dma_direct_sync_sg_for_cpu/device dma-direct: only limit the mapping size if swiotlb could be used dma-mapping: add a dma_addressing_limited helper dma-direct: Force unencrypted DMA under SME for certain DMA masks
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/Kconfig1
-rw-r--r--arch/x86/mm/mem_encrypt.c30
2 files changed, 31 insertions, 0 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 78772870facd..222855cc0158 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1526,6 +1526,7 @@ config AMD_MEM_ENCRYPT
depends on X86_64 && CPU_SUP_AMD
select DYNAMIC_PHYSICAL_MASK
select ARCH_USE_MEMREMAP_PROT
+ select ARCH_HAS_FORCE_DMA_UNENCRYPTED
---help---
Say yes to enable support for the encryption of system memory.
This requires an AMD processor that supports Secure Memory
diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index e94e0a62ba92..fece30ca8b0c 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c
@@ -15,6 +15,10 @@
#include <linux/dma-direct.h>
#include <linux/swiotlb.h>
#include <linux/mem_encrypt.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/bitops.h>
+#include <linux/dma-mapping.h>
#include <asm/tlbflush.h>
#include <asm/fixmap.h>
@@ -348,6 +352,32 @@ bool sev_active(void)
}
EXPORT_SYMBOL(sev_active);
+/* Override for DMA direct allocation check - ARCH_HAS_FORCE_DMA_UNENCRYPTED */
+bool force_dma_unencrypted(struct device *dev)
+{
+ /*
+ * For SEV, all DMA must be to unencrypted addresses.
+ */
+ if (sev_active())
+ return true;
+
+ /*
+ * For SME, all DMA must be to unencrypted addresses if the
+ * device does not support DMA to addresses that include the
+ * encryption mask.
+ */
+ if (sme_active()) {
+ u64 dma_enc_mask = DMA_BIT_MASK(__ffs64(sme_me_mask));
+ u64 dma_dev_mask = min_not_zero(dev->coherent_dma_mask,
+ dev->bus_dma_mask);
+
+ if (dma_dev_mask <= dma_enc_mask)
+ return true;
+ }
+
+ return false;
+}
+
/* Architecture __weak replacement functions */
void __init mem_encrypt_free_decrypted_mem(void)
{