// SPDX-License-Identifier: GPL-2.0+ /* * Secure VM platform * * Copyright 2018 IBM Corporation * Author: Anshuman Khandual <khandual@linux.vnet.ibm.com> */ #include <linux/mm.h> #include <linux/memblock.h> #include <asm/machdep.h> #include <asm/svm.h> #include <asm/swiotlb.h> #include <asm/ultravisor.h> #include <asm/dtl.h> static int __init init_svm(void) { if (!is_secure_guest()) return 0; /* Don't release the SWIOTLB buffer. */ ppc_swiotlb_enable = 1; /* * Since the guest memory is inaccessible to the host, devices always * need to use the SWIOTLB buffer for DMA even if dma_capable() says * otherwise. */ swiotlb_force = SWIOTLB_FORCE; /* Share the SWIOTLB buffer with the host. */ swiotlb_update_mem_attributes(); return 0; } machine_early_initcall(pseries, init_svm); /* * Initialize SWIOTLB. Essentially the same as swiotlb_init(), except that it * can allocate the buffer anywhere in memory. Since the hypervisor doesn't have * any addressing limitation, we don't need to allocate it in low addresses. */ void __init svm_swiotlb_init(void) { unsigned char *vstart; unsigned long bytes, io_tlb_nslabs; io_tlb_nslabs = (swiotlb_size_or_default() >> IO_TLB_SHIFT); io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE); bytes = io_tlb_nslabs << IO_TLB_SHIFT; vstart = memblock_alloc(PAGE_ALIGN(bytes), PAGE_SIZE); if (vstart && !swiotlb_init_with_tbl(vstart, io_tlb_nslabs, false)) return; if (io_tlb_start) memblock_free_early(io_tlb_start, PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT)); panic("SVM: Cannot allocate SWIOTLB buffer"); } int set_memory_encrypted(unsigned long addr, int numpages) { if (!PAGE_ALIGNED(addr)) return -EINVAL; uv_unshare_page(PHYS_PFN(__pa(addr)), numpages); return 0; } int set_memory_decrypted(unsigned long addr, int numpages) { if (!PAGE_ALIGNED(addr)) return -EINVAL; uv_share_page(PHYS_PFN(__pa(addr)), numpages); return 0; } /* There's one dispatch log per CPU. */ #define NR_DTL_PAGE (DISPATCH_LOG_BYTES * CONFIG_NR_CPUS / PAGE_SIZE) static struct page *dtl_page_store[NR_DTL_PAGE]; static long dtl_nr_pages; static bool is_dtl_page_shared(struct page *page) { long i; for (i = 0; i < dtl_nr_pages; i++) if (dtl_page_store[i] == page) return true; return false; } void dtl_cache_ctor(void *addr) { unsigned long pfn = PHYS_PFN(__pa(addr)); struct page *page = pfn_to_page(pfn); if (!is_dtl_page_shared(page)) { dtl_page_store[dtl_nr_pages] = page; dtl_nr_pages++; WARN_ON(dtl_nr_pages >= NR_DTL_PAGE); uv_share_page(pfn, 1); } }