1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0+
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Secure VM platform
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Copyright 2018 IBM Corporation
6*4882a593Smuzhiyun * Author: Anshuman Khandual <khandual@linux.vnet.ibm.com>
7*4882a593Smuzhiyun */
8*4882a593Smuzhiyun
9*4882a593Smuzhiyun #include <linux/mm.h>
10*4882a593Smuzhiyun #include <linux/memblock.h>
11*4882a593Smuzhiyun #include <asm/machdep.h>
12*4882a593Smuzhiyun #include <asm/svm.h>
13*4882a593Smuzhiyun #include <asm/swiotlb.h>
14*4882a593Smuzhiyun #include <asm/ultravisor.h>
15*4882a593Smuzhiyun #include <asm/dtl.h>
16*4882a593Smuzhiyun
init_svm(void)17*4882a593Smuzhiyun static int __init init_svm(void)
18*4882a593Smuzhiyun {
19*4882a593Smuzhiyun if (!is_secure_guest())
20*4882a593Smuzhiyun return 0;
21*4882a593Smuzhiyun
22*4882a593Smuzhiyun /* Don't release the SWIOTLB buffer. */
23*4882a593Smuzhiyun ppc_swiotlb_enable = 1;
24*4882a593Smuzhiyun
25*4882a593Smuzhiyun /*
26*4882a593Smuzhiyun * Since the guest memory is inaccessible to the host, devices always
27*4882a593Smuzhiyun * need to use the SWIOTLB buffer for DMA even if dma_capable() says
28*4882a593Smuzhiyun * otherwise.
29*4882a593Smuzhiyun */
30*4882a593Smuzhiyun swiotlb_force = SWIOTLB_FORCE;
31*4882a593Smuzhiyun
32*4882a593Smuzhiyun /* Share the SWIOTLB buffer with the host. */
33*4882a593Smuzhiyun swiotlb_update_mem_attributes();
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun return 0;
36*4882a593Smuzhiyun }
37*4882a593Smuzhiyun machine_early_initcall(pseries, init_svm);
38*4882a593Smuzhiyun
39*4882a593Smuzhiyun /*
40*4882a593Smuzhiyun * Initialize SWIOTLB. Essentially the same as swiotlb_init(), except that it
41*4882a593Smuzhiyun * can allocate the buffer anywhere in memory. Since the hypervisor doesn't have
42*4882a593Smuzhiyun * any addressing limitation, we don't need to allocate it in low addresses.
43*4882a593Smuzhiyun */
svm_swiotlb_init(void)44*4882a593Smuzhiyun void __init svm_swiotlb_init(void)
45*4882a593Smuzhiyun {
46*4882a593Smuzhiyun unsigned char *vstart;
47*4882a593Smuzhiyun unsigned long bytes, io_tlb_nslabs;
48*4882a593Smuzhiyun
49*4882a593Smuzhiyun io_tlb_nslabs = (swiotlb_size_or_default() >> IO_TLB_SHIFT);
50*4882a593Smuzhiyun io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
51*4882a593Smuzhiyun
52*4882a593Smuzhiyun bytes = io_tlb_nslabs << IO_TLB_SHIFT;
53*4882a593Smuzhiyun
54*4882a593Smuzhiyun vstart = memblock_alloc(PAGE_ALIGN(bytes), PAGE_SIZE);
55*4882a593Smuzhiyun if (vstart && !swiotlb_init_with_tbl(vstart, io_tlb_nslabs, false))
56*4882a593Smuzhiyun return;
57*4882a593Smuzhiyun
58*4882a593Smuzhiyun if (io_tlb_start)
59*4882a593Smuzhiyun memblock_free_early(io_tlb_start,
60*4882a593Smuzhiyun PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT));
61*4882a593Smuzhiyun panic("SVM: Cannot allocate SWIOTLB buffer");
62*4882a593Smuzhiyun }
63*4882a593Smuzhiyun
set_memory_encrypted(unsigned long addr,int numpages)64*4882a593Smuzhiyun int set_memory_encrypted(unsigned long addr, int numpages)
65*4882a593Smuzhiyun {
66*4882a593Smuzhiyun if (!PAGE_ALIGNED(addr))
67*4882a593Smuzhiyun return -EINVAL;
68*4882a593Smuzhiyun
69*4882a593Smuzhiyun uv_unshare_page(PHYS_PFN(__pa(addr)), numpages);
70*4882a593Smuzhiyun
71*4882a593Smuzhiyun return 0;
72*4882a593Smuzhiyun }
73*4882a593Smuzhiyun
set_memory_decrypted(unsigned long addr,int numpages)74*4882a593Smuzhiyun int set_memory_decrypted(unsigned long addr, int numpages)
75*4882a593Smuzhiyun {
76*4882a593Smuzhiyun if (!PAGE_ALIGNED(addr))
77*4882a593Smuzhiyun return -EINVAL;
78*4882a593Smuzhiyun
79*4882a593Smuzhiyun uv_share_page(PHYS_PFN(__pa(addr)), numpages);
80*4882a593Smuzhiyun
81*4882a593Smuzhiyun return 0;
82*4882a593Smuzhiyun }
83*4882a593Smuzhiyun
84*4882a593Smuzhiyun /* There's one dispatch log per CPU. */
85*4882a593Smuzhiyun #define NR_DTL_PAGE (DISPATCH_LOG_BYTES * CONFIG_NR_CPUS / PAGE_SIZE)
86*4882a593Smuzhiyun
87*4882a593Smuzhiyun static struct page *dtl_page_store[NR_DTL_PAGE];
88*4882a593Smuzhiyun static long dtl_nr_pages;
89*4882a593Smuzhiyun
is_dtl_page_shared(struct page * page)90*4882a593Smuzhiyun static bool is_dtl_page_shared(struct page *page)
91*4882a593Smuzhiyun {
92*4882a593Smuzhiyun long i;
93*4882a593Smuzhiyun
94*4882a593Smuzhiyun for (i = 0; i < dtl_nr_pages; i++)
95*4882a593Smuzhiyun if (dtl_page_store[i] == page)
96*4882a593Smuzhiyun return true;
97*4882a593Smuzhiyun
98*4882a593Smuzhiyun return false;
99*4882a593Smuzhiyun }
100*4882a593Smuzhiyun
dtl_cache_ctor(void * addr)101*4882a593Smuzhiyun void dtl_cache_ctor(void *addr)
102*4882a593Smuzhiyun {
103*4882a593Smuzhiyun unsigned long pfn = PHYS_PFN(__pa(addr));
104*4882a593Smuzhiyun struct page *page = pfn_to_page(pfn);
105*4882a593Smuzhiyun
106*4882a593Smuzhiyun if (!is_dtl_page_shared(page)) {
107*4882a593Smuzhiyun dtl_page_store[dtl_nr_pages] = page;
108*4882a593Smuzhiyun dtl_nr_pages++;
109*4882a593Smuzhiyun WARN_ON(dtl_nr_pages >= NR_DTL_PAGE);
110*4882a593Smuzhiyun uv_share_page(pfn, 1);
111*4882a593Smuzhiyun }
112*4882a593Smuzhiyun }
113