xref: /OK3568_Linux_fs/kernel/arch/arm64/kvm/hyp/reserved_mem.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * Copyright (C) 2020 - Google LLC
4*4882a593Smuzhiyun  * Author: Quentin Perret <qperret@google.com>
5*4882a593Smuzhiyun  */
6*4882a593Smuzhiyun 
7*4882a593Smuzhiyun #include <linux/kvm_host.h>
8*4882a593Smuzhiyun #include <linux/memblock.h>
9*4882a593Smuzhiyun #include <linux/sort.h>
10*4882a593Smuzhiyun 
11*4882a593Smuzhiyun #include <asm/kvm_host.h>
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun #include <nvhe/memory.h>
14*4882a593Smuzhiyun #include <nvhe/mm.h>
15*4882a593Smuzhiyun 
16*4882a593Smuzhiyun static struct memblock_region *hyp_memory = kvm_nvhe_sym(hyp_memory);
17*4882a593Smuzhiyun static unsigned int *hyp_memblock_nr_ptr = &kvm_nvhe_sym(hyp_memblock_nr);
18*4882a593Smuzhiyun 
19*4882a593Smuzhiyun phys_addr_t hyp_mem_base;
20*4882a593Smuzhiyun phys_addr_t hyp_mem_size;
21*4882a593Smuzhiyun 
cmp_hyp_memblock(const void * p1,const void * p2)22*4882a593Smuzhiyun static int cmp_hyp_memblock(const void *p1, const void *p2)
23*4882a593Smuzhiyun {
24*4882a593Smuzhiyun 	const struct memblock_region *r1 = p1;
25*4882a593Smuzhiyun 	const struct memblock_region *r2 = p2;
26*4882a593Smuzhiyun 
27*4882a593Smuzhiyun 	return r1->base < r2->base ? -1 : (r1->base > r2->base);
28*4882a593Smuzhiyun }
29*4882a593Smuzhiyun 
sort_memblock_regions(void)30*4882a593Smuzhiyun static void __init sort_memblock_regions(void)
31*4882a593Smuzhiyun {
32*4882a593Smuzhiyun 	sort(hyp_memory,
33*4882a593Smuzhiyun 	     *hyp_memblock_nr_ptr,
34*4882a593Smuzhiyun 	     sizeof(struct memblock_region),
35*4882a593Smuzhiyun 	     cmp_hyp_memblock,
36*4882a593Smuzhiyun 	     NULL);
37*4882a593Smuzhiyun }
38*4882a593Smuzhiyun 
register_memblock_regions(void)39*4882a593Smuzhiyun static int __init register_memblock_regions(void)
40*4882a593Smuzhiyun {
41*4882a593Smuzhiyun 	struct memblock_region *reg;
42*4882a593Smuzhiyun 
43*4882a593Smuzhiyun 	for_each_mem_region(reg) {
44*4882a593Smuzhiyun 		if (*hyp_memblock_nr_ptr >= HYP_MEMBLOCK_REGIONS)
45*4882a593Smuzhiyun 			return -ENOMEM;
46*4882a593Smuzhiyun 
47*4882a593Smuzhiyun 		hyp_memory[*hyp_memblock_nr_ptr] = *reg;
48*4882a593Smuzhiyun 		(*hyp_memblock_nr_ptr)++;
49*4882a593Smuzhiyun 	}
50*4882a593Smuzhiyun 	sort_memblock_regions();
51*4882a593Smuzhiyun 
52*4882a593Smuzhiyun 	return 0;
53*4882a593Smuzhiyun }
54*4882a593Smuzhiyun 
kvm_hyp_reserve(void)55*4882a593Smuzhiyun void __init kvm_hyp_reserve(void)
56*4882a593Smuzhiyun {
57*4882a593Smuzhiyun 	u64 nr_pages, prev, hyp_mem_pages = 0;
58*4882a593Smuzhiyun 	int ret;
59*4882a593Smuzhiyun 
60*4882a593Smuzhiyun 	if (!is_hyp_mode_available() || is_kernel_in_hyp_mode())
61*4882a593Smuzhiyun 		return;
62*4882a593Smuzhiyun 
63*4882a593Smuzhiyun 	if (kvm_get_mode() != KVM_MODE_PROTECTED)
64*4882a593Smuzhiyun 		return;
65*4882a593Smuzhiyun 
66*4882a593Smuzhiyun 	ret = register_memblock_regions();
67*4882a593Smuzhiyun 	if (ret) {
68*4882a593Smuzhiyun 		*hyp_memblock_nr_ptr = 0;
69*4882a593Smuzhiyun 		kvm_err("Failed to register hyp memblocks: %d\n", ret);
70*4882a593Smuzhiyun 		return;
71*4882a593Smuzhiyun 	}
72*4882a593Smuzhiyun 
73*4882a593Smuzhiyun 	hyp_mem_pages += hyp_s1_pgtable_pages();
74*4882a593Smuzhiyun 	hyp_mem_pages += host_s2_mem_pgtable_pages();
75*4882a593Smuzhiyun 	hyp_mem_pages += host_s2_dev_pgtable_pages();
76*4882a593Smuzhiyun 
77*4882a593Smuzhiyun 	/*
78*4882a593Smuzhiyun 	 * The hyp_vmemmap needs to be backed by pages, but these pages
79*4882a593Smuzhiyun 	 * themselves need to be present in the vmemmap, so compute the number
80*4882a593Smuzhiyun 	 * of pages needed by looking for a fixed point.
81*4882a593Smuzhiyun 	 */
82*4882a593Smuzhiyun 	nr_pages = 0;
83*4882a593Smuzhiyun 	do {
84*4882a593Smuzhiyun 		prev = nr_pages;
85*4882a593Smuzhiyun 		nr_pages = hyp_mem_pages + prev;
86*4882a593Smuzhiyun 		nr_pages = DIV_ROUND_UP(nr_pages * sizeof(struct hyp_page), PAGE_SIZE);
87*4882a593Smuzhiyun 		nr_pages += __hyp_pgtable_max_pages(nr_pages);
88*4882a593Smuzhiyun 	} while (nr_pages != prev);
89*4882a593Smuzhiyun 	hyp_mem_pages += nr_pages;
90*4882a593Smuzhiyun 
91*4882a593Smuzhiyun 	/*
92*4882a593Smuzhiyun 	 * Try to allocate a PMD-aligned region to reduce TLB pressure once
93*4882a593Smuzhiyun 	 * this is unmapped from the host stage-2, and fallback to PAGE_SIZE.
94*4882a593Smuzhiyun 	 */
95*4882a593Smuzhiyun 	hyp_mem_size = hyp_mem_pages << PAGE_SHIFT;
96*4882a593Smuzhiyun 	hyp_mem_base = memblock_find_in_range(0, memblock_end_of_DRAM(),
97*4882a593Smuzhiyun 					      ALIGN(hyp_mem_size, PMD_SIZE),
98*4882a593Smuzhiyun 					      PMD_SIZE);
99*4882a593Smuzhiyun 	if (!hyp_mem_base)
100*4882a593Smuzhiyun 		hyp_mem_base = memblock_find_in_range(0, memblock_end_of_DRAM(),
101*4882a593Smuzhiyun 						      hyp_mem_size, PAGE_SIZE);
102*4882a593Smuzhiyun 	else
103*4882a593Smuzhiyun 		hyp_mem_size = ALIGN(hyp_mem_size, PMD_SIZE);
104*4882a593Smuzhiyun 
105*4882a593Smuzhiyun 	if (!hyp_mem_base) {
106*4882a593Smuzhiyun 		kvm_err("Failed to reserve hyp memory\n");
107*4882a593Smuzhiyun 		return;
108*4882a593Smuzhiyun 	}
109*4882a593Smuzhiyun 	memblock_reserve(hyp_mem_base, hyp_mem_size);
110*4882a593Smuzhiyun 
111*4882a593Smuzhiyun 	kvm_info("Reserved %lld MiB at 0x%llx\n", hyp_mem_size >> 20,
112*4882a593Smuzhiyun 		 hyp_mem_base);
113*4882a593Smuzhiyun }
114