| 1 | // SPDX-License-Identifier: GPL-2.0+ |
|---|---|
| 2 | /* |
| 3 | * Secure VM platform |
| 4 | * |
| 5 | * Copyright 2018 IBM Corporation |
| 6 | * Author: Anshuman Khandual <khandual@linux.vnet.ibm.com> |
| 7 | */ |
| 8 | |
| 9 | #include <linux/mm.h> |
| 10 | #include <linux/memblock.h> |
| 11 | #include <linux/mem_encrypt.h> |
| 12 | #include <linux/cc_platform.h> |
| 13 | #include <asm/machdep.h> |
| 14 | #include <asm/svm.h> |
| 15 | #include <asm/swiotlb.h> |
| 16 | #include <asm/ultravisor.h> |
| 17 | #include <asm/dtl.h> |
| 18 | |
| 19 | static int __init init_svm(void) |
| 20 | { |
| 21 | if (!is_secure_guest()) |
| 22 | return 0; |
| 23 | |
| 24 | /* Don't release the SWIOTLB buffer. */ |
| 25 | ppc_swiotlb_enable = 1; |
| 26 | |
| 27 | /* |
| 28 | * Since the guest memory is inaccessible to the host, devices always |
| 29 | * need to use the SWIOTLB buffer for DMA even if dma_capable() says |
| 30 | * otherwise. |
| 31 | */ |
| 32 | ppc_swiotlb_flags |= SWIOTLB_ANY | SWIOTLB_FORCE; |
| 33 | |
| 34 | /* Share the SWIOTLB buffer with the host. */ |
| 35 | swiotlb_update_mem_attributes(); |
| 36 | |
| 37 | return 0; |
| 38 | } |
| 39 | machine_early_initcall(pseries, init_svm); |
| 40 | |
| 41 | int set_memory_encrypted(unsigned long addr, int numpages) |
| 42 | { |
| 43 | if (!cc_platform_has(attr: CC_ATTR_MEM_ENCRYPT)) |
| 44 | return 0; |
| 45 | |
| 46 | if (!PAGE_ALIGNED(addr)) |
| 47 | return -EINVAL; |
| 48 | |
| 49 | uv_unshare_page(PHYS_PFN(__pa(addr)), numpages); |
| 50 | |
| 51 | return 0; |
| 52 | } |
| 53 | |
| 54 | int set_memory_decrypted(unsigned long addr, int numpages) |
| 55 | { |
| 56 | if (!cc_platform_has(attr: CC_ATTR_MEM_ENCRYPT)) |
| 57 | return 0; |
| 58 | |
| 59 | if (!PAGE_ALIGNED(addr)) |
| 60 | return -EINVAL; |
| 61 | |
| 62 | uv_share_page(PHYS_PFN(__pa(addr)), numpages); |
| 63 | |
| 64 | return 0; |
| 65 | } |
| 66 | |
| 67 | /* There's one dispatch log per CPU. */ |
| 68 | #define NR_DTL_PAGE (DISPATCH_LOG_BYTES * CONFIG_NR_CPUS / PAGE_SIZE) |
| 69 | |
| 70 | static struct page *dtl_page_store[NR_DTL_PAGE]; |
| 71 | static long dtl_nr_pages; |
| 72 | |
| 73 | static bool is_dtl_page_shared(struct page *page) |
| 74 | { |
| 75 | long i; |
| 76 | |
| 77 | for (i = 0; i < dtl_nr_pages; i++) |
| 78 | if (dtl_page_store[i] == page) |
| 79 | return true; |
| 80 | |
| 81 | return false; |
| 82 | } |
| 83 | |
| 84 | void dtl_cache_ctor(void *addr) |
| 85 | { |
| 86 | unsigned long pfn = PHYS_PFN(__pa(addr)); |
| 87 | struct page *page = pfn_to_page(pfn); |
| 88 | |
| 89 | if (!is_dtl_page_shared(page)) { |
| 90 | dtl_page_store[dtl_nr_pages] = page; |
| 91 | dtl_nr_pages++; |
| 92 | WARN_ON(dtl_nr_pages >= NR_DTL_PAGE); |
| 93 | uv_share_page(pfn, 1); |
| 94 | } |
| 95 | } |
| 96 |