diff options
| author | Tom Lendacky <thomas.lendacky@amd.com> | 2017-07-17 16:10:21 -0500 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-07-18 11:38:03 +0200 |
| commit | c7753208a94c73d5beb1e4bd843081d6dc7d4678 (patch) | |
| tree | 9206890b53db25e5619f3affe170f0bd9feb7e25 /arch/x86/kernel/pci-swiotlb.c | |
| parent | 163ea3c83aeeb3908a51162c79cb3a7c374d92b4 (diff) | |
x86, swiotlb: Add memory encryption support
Since DMA addresses will effectively look like 48-bit addresses when the
memory encryption mask is set, SWIOTLB is needed if the DMA mask of the
device performing the DMA does not support 48-bits. SWIOTLB will be
initialized to create decrypted bounce buffers for use by these devices.
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Toshimitsu Kani <toshi.kani@hpe.com>
Cc: kasan-dev@googlegroups.com
Cc: kvm@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-efi@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/aa2d29b78ae7d508db8881e46a3215231b9327a7.1500319216.git.thomas.lendacky@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/pci-swiotlb.c')
| -rw-r--r-- | arch/x86/kernel/pci-swiotlb.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/arch/x86/kernel/pci-swiotlb.c b/arch/x86/kernel/pci-swiotlb.c index 1e23577e17cf..677077510e30 100644 --- a/arch/x86/kernel/pci-swiotlb.c +++ b/arch/x86/kernel/pci-swiotlb.c @@ -6,12 +6,14 @@ #include <linux/swiotlb.h> #include <linux/bootmem.h> #include <linux/dma-mapping.h> +#include <linux/mem_encrypt.h> #include <asm/iommu.h> #include <asm/swiotlb.h> #include <asm/dma.h> #include <asm/xen/swiotlb-xen.h> #include <asm/iommu_table.h> + int swiotlb __read_mostly; void *x86_swiotlb_alloc_coherent(struct device *hwdev, size_t size, @@ -79,8 +81,8 @@ IOMMU_INIT_FINISH(pci_swiotlb_detect_override, pci_swiotlb_late_init); /* - * if 4GB or more detected (and iommu=off not set) return 1 - * and set swiotlb to 1. + * If 4GB or more detected (and iommu=off not set) or if SME is active + * then set swiotlb to 1 and return 1. */ int __init pci_swiotlb_detect_4gb(void) { @@ -89,6 +91,15 @@ int __init pci_swiotlb_detect_4gb(void) if (!no_iommu && max_possible_pfn > MAX_DMA32_PFN) swiotlb = 1; #endif + + /* + * If SME is active then swiotlb will be set to 1 so that bounce + * buffers are allocated and used for devices that do not support + * the addressing range required for the encryption mask. + */ + if (sme_active()) + swiotlb = 1; + return swiotlb; } IOMMU_INIT(pci_swiotlb_detect_4gb, |