| 1 | // SPDX-License-Identifier: GPL-2.0-only |
|---|---|
| 2 | /* |
| 3 | * Implementation of the memory encryption/decryption API. |
| 4 | * |
| 5 | * Since the low-level details of the operation depend on the |
| 6 | * Confidential Computing environment (e.g. pKVM, CCA, ...), this just |
| 7 | * acts as a top-level dispatcher to whatever hooks may have been |
| 8 | * registered. |
| 9 | * |
| 10 | * Author: Will Deacon <will@kernel.org> |
| 11 | * Copyright (C) 2024 Google LLC |
| 12 | * |
| 13 | * "Hello, boils and ghouls!" |
| 14 | */ |
| 15 | |
| 16 | #include <linux/bug.h> |
| 17 | #include <linux/compiler.h> |
| 18 | #include <linux/err.h> |
| 19 | #include <linux/mm.h> |
| 20 | |
| 21 | #include <asm/mem_encrypt.h> |
| 22 | |
| 23 | static const struct arm64_mem_crypt_ops *crypt_ops; |
| 24 | |
| 25 | int arm64_mem_crypt_ops_register(const struct arm64_mem_crypt_ops *ops) |
| 26 | { |
| 27 | if (WARN_ON(crypt_ops)) |
| 28 | return -EBUSY; |
| 29 | |
| 30 | crypt_ops = ops; |
| 31 | return 0; |
| 32 | } |
| 33 | |
| 34 | int set_memory_encrypted(unsigned long addr, int numpages) |
| 35 | { |
| 36 | if (likely(!crypt_ops) || WARN_ON(!PAGE_ALIGNED(addr))) |
| 37 | return 0; |
| 38 | |
| 39 | return crypt_ops->encrypt(addr, numpages); |
| 40 | } |
| 41 | EXPORT_SYMBOL_GPL(set_memory_encrypted); |
| 42 | |
| 43 | int set_memory_decrypted(unsigned long addr, int numpages) |
| 44 | { |
| 45 | if (likely(!crypt_ops) || WARN_ON(!PAGE_ALIGNED(addr))) |
| 46 | return 0; |
| 47 | |
| 48 | return crypt_ops->decrypt(addr, numpages); |
| 49 | } |
| 50 | EXPORT_SYMBOL_GPL(set_memory_decrypted); |
| 51 |