arch/arm64/include/asm/mem_encrypt.h

File Facts

System

Linux kernel

Corpus path

arch/arm64/include/asm/mem_encrypt.h

Extension

.h

Size

1015 bytes

Lines

38

Domain

Architecture Layer

Bucket

arch/arm64

Inferred role

Architecture Layer: implementation source

Status

source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

• CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• asm/rsi.h

Detected Declarations

• struct device
• struct arm64_mem_crypt_ops
• function force_dma_unencrypted

Annotated Snippet

struct arm64_mem_crypt_ops {
	int (*encrypt)(unsigned long addr, int numpages);
	int (*decrypt)(unsigned long addr, int numpages);
};

int arm64_mem_crypt_ops_register(const struct arm64_mem_crypt_ops *ops);

int set_memory_encrypted(unsigned long addr, int numpages);
int set_memory_decrypted(unsigned long addr, int numpages);

int realm_register_memory_enc_ops(void);

static inline bool force_dma_unencrypted(struct device *dev)
{
	return is_realm_world();
}

/*
 * For Arm CCA guests, canonical addresses are "encrypted", so no changes
 * required for dma_addr_encrypted().
 * The unencrypted DMA buffers must be accessed via the unprotected IPA,
 * "top IPA bit" set.
 */
#define dma_addr_unencrypted(x)		((x) | PROT_NS_SHARED)

/* Clear the "top" IPA bit while converting back */
#define dma_addr_canonical(x)		((x) & ~PROT_NS_SHARED)

#endif	/* __ASM_MEM_ENCRYPT_H */

Annotation

• Immediate include surface: `asm/rsi.h`.
• Detected declarations: `struct device`, `struct arm64_mem_crypt_ops`, `function force_dma_unencrypted`.
• Atlas domain: Architecture Layer / arch/arm64.
• Implementation status: source implementation candidate.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.