xref: /openbmc/linux/arch/arm64/kvm/hyp/nvhe/early_alloc.c (revision 63705da3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2020 Google LLC
4  * Author: Quentin Perret <qperret@google.com>
5  */
6 
7 #include <asm/kvm_pgtable.h>
8 
9 #include <nvhe/early_alloc.h>
10 #include <nvhe/memory.h>
11 
12 struct kvm_pgtable_mm_ops hyp_early_alloc_mm_ops;
13 s64 __ro_after_init hyp_physvirt_offset;
14 
15 static unsigned long base;
16 static unsigned long end;
17 static unsigned long cur;
18 
19 unsigned long hyp_early_alloc_nr_used_pages(void)
20 {
21 	return (cur - base) >> PAGE_SHIFT;
22 }
23 
24 void *hyp_early_alloc_contig(unsigned int nr_pages)
25 {
26 	unsigned long size = (nr_pages << PAGE_SHIFT);
27 	void *ret = (void *)cur;
28 
29 	if (!nr_pages)
30 		return NULL;
31 
32 	if (end - cur < size)
33 		return NULL;
34 
35 	cur += size;
36 	memset(ret, 0, size);
37 
38 	return ret;
39 }
40 
41 void *hyp_early_alloc_page(void *arg)
42 {
43 	return hyp_early_alloc_contig(1);
44 }
45 
46 void hyp_early_alloc_init(void *virt, unsigned long size)
47 {
48 	base = cur = (unsigned long)virt;
49 	end = base + size;
50 
51 	hyp_early_alloc_mm_ops.zalloc_page = hyp_early_alloc_page;
52 	hyp_early_alloc_mm_ops.phys_to_virt = hyp_phys_to_virt;
53 	hyp_early_alloc_mm_ops.virt_to_phys = hyp_virt_to_phys;
54 }
55