linux/arch/x86/include/asm/coco.h
Kirill A. Shutemov b577f542f9 x86/coco: Add API to handle encryption mask
AMD SME/SEV uses a bit in the page table entries to indicate that the
page is encrypted and not accessible to the VMM.

TDX uses a similar approach, but the polarity of the mask is opposite to
AMD: if the bit is set the page is accessible to VMM.

Provide vendor-neutral API to deal with the mask: cc_mkenc() and
cc_mkdec() modify given address to make it encrypted/decrypted. It can
be applied to phys_addr_t, pgprotval_t or page table entry value.

pgprot_encrypted() and pgprot_decrypted() reimplemented using new
helpers.

The implementation will be extended to cover TDX.

pgprot_decrypted() is used by drivers (i915, virtio_gpu, vfio).
cc_mkdec() called by pgprot_decrypted(). Export cc_mkdec().

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20220222185740.26228-5-kirill.shutemov@linux.intel.com
2022-02-23 19:14:29 +01:00

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C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_COCO_H
#define _ASM_X86_COCO_H
#include <asm/types.h>
enum cc_vendor {
CC_VENDOR_NONE,
CC_VENDOR_AMD,
CC_VENDOR_HYPERV,
CC_VENDOR_INTEL,
};
void cc_set_vendor(enum cc_vendor v);
void cc_set_mask(u64 mask);
#ifdef CONFIG_ARCH_HAS_CC_PLATFORM
u64 cc_mkenc(u64 val);
u64 cc_mkdec(u64 val);
#else
static inline u64 cc_mkenc(u64 val)
{
return val;
}
static inline u64 cc_mkdec(u64 val)
{
return val;
}
#endif
#endif /* _ASM_X86_COCO_H */