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