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 <linux/mem_encrypt.h> 14 #include <asm/machdep.h> 15 #include <asm/svm.h> 16 #include <asm/swiotlb.h> 17 #include <asm/ultravisor.h> 18 #include <asm/dtl.h> 19 20 static int __init init_svm(void) 21 { 22 if (!is_secure_guest()) 23 return 0; 24 25 /* Don't release the SWIOTLB buffer. */ 26 ppc_swiotlb_enable = 1; 27 28 /* 29 * Since the guest memory is inaccessible to the host, devices always 30 * need to use the SWIOTLB buffer for DMA even if dma_capable() says 31 * otherwise. 32 */ 33 ppc_swiotlb_flags |= SWIOTLB_ANY | SWIOTLB_FORCE; 34 35 /* Share the SWIOTLB buffer with the host. */ 36 swiotlb_update_mem_attributes(); 37 38 return 0; 39 } 40 machine_early_initcall(pseries, init_svm); 41 42 int set_memory_encrypted(unsigned long addr, int numpages) 43 { 44 if (!cc_platform_has(CC_ATTR_MEM_ENCRYPT)) 45 return 0; 46 47 if (!PAGE_ALIGNED(addr)) 48 return -EINVAL; 49 50 uv_unshare_page(PHYS_PFN(__pa(addr)), numpages); 51 52 return 0; 53 } 54 55 int set_memory_decrypted(unsigned long addr, int numpages) 56 { 57 if (!cc_platform_has(CC_ATTR_MEM_ENCRYPT)) 58 return 0; 59 60 if (!PAGE_ALIGNED(addr)) 61 return -EINVAL; 62 63 uv_share_page(PHYS_PFN(__pa(addr)), numpages); 64 65 return 0; 66 } 67 68 /* There's one dispatch log per CPU. */ 69 #define NR_DTL_PAGE (DISPATCH_LOG_BYTES * CONFIG_NR_CPUS / PAGE_SIZE) 70 71 static struct page *dtl_page_store[NR_DTL_PAGE]; 72 static long dtl_nr_pages; 73 74 static bool is_dtl_page_shared(struct page *page) 75 { 76 long i; 77 78 for (i = 0; i < dtl_nr_pages; i++) 79 if (dtl_page_store[i] == page) 80 return true; 81 82 return false; 83 } 84 85 void dtl_cache_ctor(void *addr) 86 { 87 unsigned long pfn = PHYS_PFN(__pa(addr)); 88 struct page *page = pfn_to_page(pfn); 89 90 if (!is_dtl_page_shared(page)) { 91 dtl_page_store[dtl_nr_pages] = page; 92 dtl_nr_pages++; 93 WARN_ON(dtl_nr_pages >= NR_DTL_PAGE); 94 uv_share_page(pfn, 1); 95 } 96 } 97