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130 lines · 2.6 KiB

1// SPDX-License-Identifier: GPL-2.0
2
3/*
4 * Hyper-V nested virtualization code.
5 *
6 * Copyright (C) 2018, Microsoft, Inc.
7 *
8 * Author : Lan Tianyu <[email protected]>
9 */
10#define pr_fmt(fmt) "Hyper-V: " fmt
11
12
13#include <linux/types.h>
14#include <linux/export.h>
15#include <hyperv/hvhdk.h>
16#include <asm/mshyperv.h>
17#include <asm/tlbflush.h>
18
19#include <asm/trace/hyperv.h>
20
21int hyperv_flush_guest_mapping(u64 as)
22{
23 struct hv_guest_mapping_flush *flush;
24 u64 status;
25 unsigned long flags;
26 int ret = -ENOTSUPP;
27
28 if (!hv_hypercall_pg)
29 goto fault;
30
31 local_irq_save(flags);
32
33 flush = *this_cpu_ptr(hyperv_pcpu_input_arg);
34
35 if (unlikely(!flush)) {
36 local_irq_restore(flags);
37 goto fault;
38 }
39
40 flush->address_space = as;
41 flush->flags = 0;
42
43 status = hv_do_hypercall(HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_SPACE,
44 flush, NULL);
45 local_irq_restore(flags);
46
47 if (hv_result_success(status))
48 ret = 0;
49
50fault:
51 trace_hyperv_nested_flush_guest_mapping(as, ret);
52 return ret;
53}
54EXPORT_SYMBOL_GPL(hyperv_flush_guest_mapping);
55
56int hyperv_fill_flush_guest_mapping_list(
57 struct hv_guest_mapping_flush_list *flush,
58 u64 start_gfn, u64 pages)
59{
60 u64 cur = start_gfn;
61 u64 additional_pages;
62 int gpa_n = 0;
63
64 do {
65 /*
66 * If flush requests exceed max flush count, go back to
67 * flush tlbs without range.
68 */
69 if (gpa_n >= HV_MAX_FLUSH_REP_COUNT)
70 return -ENOSPC;
71
72 additional_pages = min_t(u64, pages, HV_MAX_FLUSH_PAGES) - 1;
73
74 flush->gpa_list[gpa_n].page.additional_pages = additional_pages;
75 flush->gpa_list[gpa_n].page.largepage = false;
76 flush->gpa_list[gpa_n].page.basepfn = cur;
77
78 pages -= additional_pages + 1;
79 cur += additional_pages + 1;
80 gpa_n++;
81 } while (pages > 0);
82
83 return gpa_n;
84}
85EXPORT_SYMBOL_GPL(hyperv_fill_flush_guest_mapping_list);
86
87int hyperv_flush_guest_mapping_range(u64 as,
88 hyperv_fill_flush_list_func fill_flush_list_func, void *data)
89{
90 struct hv_guest_mapping_flush_list *flush;
91 u64 status;
92 unsigned long flags;
93 int ret = -ENOTSUPP;
94 int gpa_n = 0;
95
96 if (!hv_hypercall_pg || !fill_flush_list_func)
97 goto fault;
98
99 local_irq_save(flags);
100
101 flush = *this_cpu_ptr(hyperv_pcpu_input_arg);
102
103 if (unlikely(!flush)) {
104 local_irq_restore(flags);
105 goto fault;
106 }
107
108 flush->address_space = as;
109 flush->flags = 0;
110
111 gpa_n = fill_flush_list_func(flush, data);
112 if (gpa_n < 0) {
113 local_irq_restore(flags);
114 goto fault;
115 }
116
117 status = hv_do_rep_hypercall(HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_LIST,
118 gpa_n, 0, flush, NULL);
119
120 local_irq_restore(flags);
121
122 if (hv_result_success(status))
123 ret = 0;
124 else
125 ret = hv_result(status);
126fault:
127 trace_hyperv_nested_flush_guest_mapping_range(as, ret);
128 return ret;
129}
130EXPORT_SYMBOL_GPL(hyperv_flush_guest_mapping_range);