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1/* SPDX-License-Identifier: GPL-2.0 */
2
3/*
4 * Linux-specific definitions for managing interactions with Microsoft's
5 * Hyper-V hypervisor. The definitions in this file are architecture
6 * independent. See arch/<arch>/include/asm/mshyperv.h for definitions
7 * that are specific to architecture <arch>.
8 *
9 * Definitions that are specified in the Hyper-V Top Level Functional
10 * Spec (TLFS) should not go in this file, but should instead go in
11 * hyperv-tlfs.h.
12 *
13 * Copyright (C) 2019, Microsoft, Inc.
14 *
15 * Author : Michael Kelley <mikelley@microsoft.com>
16 */
17
18#ifndef _ASM_GENERIC_MSHYPERV_H
19#define _ASM_GENERIC_MSHYPERV_H
20
21#include <linux/types.h>
22#include <linux/atomic.h>
23#include <linux/bitops.h>
24#include <linux/cpumask.h>
25#include <linux/nmi.h>
26#include <asm/ptrace.h>
27#include <asm/hyperv-tlfs.h>
28
29#define VTPM_BASE_ADDRESS 0xfed40000
30
31struct ms_hyperv_info {
32 u32 features;
33 u32 priv_high;
34 u32 misc_features;
35 u32 hints;
36 u32 nested_features;
37 u32 max_vp_index;
38 u32 max_lp_index;
39 u32 isolation_config_a;
40 union {
41 u32 isolation_config_b;
42 struct {
43 u32 cvm_type : 4;
44 u32 reserved1 : 1;
45 u32 shared_gpa_boundary_active : 1;
46 u32 shared_gpa_boundary_bits : 6;
47 u32 reserved2 : 20;
48 };
49 };
50 u64 shared_gpa_boundary;
51};
52extern struct ms_hyperv_info ms_hyperv;
53extern bool hv_nested;
54
55extern void * __percpu *hyperv_pcpu_input_arg;
56extern void * __percpu *hyperv_pcpu_output_arg;
57
58extern u64 hv_do_hypercall(u64 control, void *inputaddr, void *outputaddr);
59extern u64 hv_do_fast_hypercall8(u16 control, u64 input8);
60extern bool hv_isolation_type_snp(void);
61
62/* Helper functions that provide a consistent pattern for checking Hyper-V hypercall status. */
63static inline int hv_result(u64 status)
64{
65 return status & HV_HYPERCALL_RESULT_MASK;
66}
67
68static inline bool hv_result_success(u64 status)
69{
70 return hv_result(status) == HV_STATUS_SUCCESS;
71}
72
73static inline unsigned int hv_repcomp(u64 status)
74{
75 /* Bits [43:32] of status have 'Reps completed' data. */
76 return (status & HV_HYPERCALL_REP_COMP_MASK) >>
77 HV_HYPERCALL_REP_COMP_OFFSET;
78}
79
80/*
81 * Rep hypercalls. Callers of this functions are supposed to ensure that
82 * rep_count and varhead_size comply with Hyper-V hypercall definition.
83 */
84static inline u64 hv_do_rep_hypercall(u16 code, u16 rep_count, u16 varhead_size,
85 void *input, void *output)
86{
87 u64 control = code;
88 u64 status;
89 u16 rep_comp;
90
91 control |= (u64)varhead_size << HV_HYPERCALL_VARHEAD_OFFSET;
92 control |= (u64)rep_count << HV_HYPERCALL_REP_COMP_OFFSET;
93
94 do {
95 status = hv_do_hypercall(control, input, output);
96 if (!hv_result_success(status))
97 return status;
98
99 rep_comp = hv_repcomp(status);
100
101 control &= ~HV_HYPERCALL_REP_START_MASK;
102 control |= (u64)rep_comp << HV_HYPERCALL_REP_START_OFFSET;
103
104 touch_nmi_watchdog();
105 } while (rep_comp < rep_count);
106
107 return status;
108}
109
110/* Generate the guest OS identifier as described in the Hyper-V TLFS */
111static inline u64 hv_generate_guest_id(u64 kernel_version)
112{
113 u64 guest_id;
114
115 guest_id = (((u64)HV_LINUX_VENDOR_ID) << 48);
116 guest_id |= (kernel_version << 16);
117
118 return guest_id;
119}
120
121/* Free the message slot and signal end-of-message if required */
122static inline void vmbus_signal_eom(struct hv_message *msg, u32 old_msg_type)
123{
124 /*
125 * On crash we're reading some other CPU's message page and we need
126 * to be careful: this other CPU may already had cleared the header
127 * and the host may already had delivered some other message there.
128 * In case we blindly write msg->header.message_type we're going
129 * to lose it. We can still lose a message of the same type but
130 * we count on the fact that there can only be one
131 * CHANNELMSG_UNLOAD_RESPONSE and we don't care about other messages
132 * on crash.
133 */
134 if (cmpxchg(&msg->header.message_type, old_msg_type,
135 HVMSG_NONE) != old_msg_type)
136 return;
137
138 /*
139 * The cmxchg() above does an implicit memory barrier to
140 * ensure the write to MessageType (ie set to
141 * HVMSG_NONE) happens before we read the
142 * MessagePending and EOMing. Otherwise, the EOMing
143 * will not deliver any more messages since there is
144 * no empty slot
145 */
146 if (msg->header.message_flags.msg_pending) {
147 /*
148 * This will cause message queue rescan to
149 * possibly deliver another msg from the
150 * hypervisor
151 */
152 hv_set_register(HV_REGISTER_EOM, 0);
153 }
154}
155
156void hv_setup_vmbus_handler(void (*handler)(void));
157void hv_remove_vmbus_handler(void);
158void hv_setup_stimer0_handler(void (*handler)(void));
159void hv_remove_stimer0_handler(void);
160
161void hv_setup_kexec_handler(void (*handler)(void));
162void hv_remove_kexec_handler(void);
163void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs));
164void hv_remove_crash_handler(void);
165
166extern int vmbus_interrupt;
167extern int vmbus_irq;
168
169extern bool hv_root_partition;
170
171#if IS_ENABLED(CONFIG_HYPERV)
172/*
173 * Hypervisor's notion of virtual processor ID is different from
174 * Linux' notion of CPU ID. This information can only be retrieved
175 * in the context of the calling CPU. Setup a map for easy access
176 * to this information.
177 */
178extern u32 *hv_vp_index;
179extern u32 hv_max_vp_index;
180
181extern u64 (*hv_read_reference_counter)(void);
182
183/* Sentinel value for an uninitialized entry in hv_vp_index array */
184#define VP_INVAL U32_MAX
185
186int __init hv_common_init(void);
187void __init hv_common_free(void);
188int hv_common_cpu_init(unsigned int cpu);
189int hv_common_cpu_die(unsigned int cpu);
190
191void *hv_alloc_hyperv_page(void);
192void *hv_alloc_hyperv_zeroed_page(void);
193void hv_free_hyperv_page(unsigned long addr);
194
195/**
196 * hv_cpu_number_to_vp_number() - Map CPU to VP.
197 * @cpu_number: CPU number in Linux terms
198 *
199 * This function returns the mapping between the Linux processor
200 * number and the hypervisor's virtual processor number, useful
201 * in making hypercalls and such that talk about specific
202 * processors.
203 *
204 * Return: Virtual processor number in Hyper-V terms
205 */
206static inline int hv_cpu_number_to_vp_number(int cpu_number)
207{
208 return hv_vp_index[cpu_number];
209}
210
211static inline int __cpumask_to_vpset(struct hv_vpset *vpset,
212 const struct cpumask *cpus,
213 bool (*func)(int cpu))
214{
215 int cpu, vcpu, vcpu_bank, vcpu_offset, nr_bank = 1;
216 int max_vcpu_bank = hv_max_vp_index / HV_VCPUS_PER_SPARSE_BANK;
217
218 /* vpset.valid_bank_mask can represent up to HV_MAX_SPARSE_VCPU_BANKS banks */
219 if (max_vcpu_bank >= HV_MAX_SPARSE_VCPU_BANKS)
220 return 0;
221
222 /*
223 * Clear all banks up to the maximum possible bank as hv_tlb_flush_ex
224 * structs are not cleared between calls, we risk flushing unneeded
225 * vCPUs otherwise.
226 */
227 for (vcpu_bank = 0; vcpu_bank <= max_vcpu_bank; vcpu_bank++)
228 vpset->bank_contents[vcpu_bank] = 0;
229
230 /*
231 * Some banks may end up being empty but this is acceptable.
232 */
233 for_each_cpu(cpu, cpus) {
234 if (func && func(cpu))
235 continue;
236 vcpu = hv_cpu_number_to_vp_number(cpu);
237 if (vcpu == VP_INVAL)
238 return -1;
239 vcpu_bank = vcpu / HV_VCPUS_PER_SPARSE_BANK;
240 vcpu_offset = vcpu % HV_VCPUS_PER_SPARSE_BANK;
241 __set_bit(vcpu_offset, (unsigned long *)
242 &vpset->bank_contents[vcpu_bank]);
243 if (vcpu_bank >= nr_bank)
244 nr_bank = vcpu_bank + 1;
245 }
246 vpset->valid_bank_mask = GENMASK_ULL(nr_bank - 1, 0);
247 return nr_bank;
248}
249
250/*
251 * Convert a Linux cpumask into a Hyper-V VPset. In the _skip variant,
252 * 'func' is called for each CPU present in cpumask. If 'func' returns
253 * true, that CPU is skipped -- i.e., that CPU from cpumask is *not*
254 * added to the Hyper-V VPset. If 'func' is NULL, no CPUs are
255 * skipped.
256 */
257static inline int cpumask_to_vpset(struct hv_vpset *vpset,
258 const struct cpumask *cpus)
259{
260 return __cpumask_to_vpset(vpset, cpus, NULL);
261}
262
263static inline int cpumask_to_vpset_skip(struct hv_vpset *vpset,
264 const struct cpumask *cpus,
265 bool (*func)(int cpu))
266{
267 return __cpumask_to_vpset(vpset, cpus, func);
268}
269
270void hyperv_report_panic(struct pt_regs *regs, long err, bool in_die);
271bool hv_is_hyperv_initialized(void);
272bool hv_is_hibernation_supported(void);
273enum hv_isolation_type hv_get_isolation_type(void);
274bool hv_is_isolation_supported(void);
275bool hv_isolation_type_snp(void);
276u64 hv_ghcb_hypercall(u64 control, void *input, void *output, u32 input_size);
277void hyperv_cleanup(void);
278bool hv_query_ext_cap(u64 cap_query);
279void hv_setup_dma_ops(struct device *dev, bool coherent);
280#else /* CONFIG_HYPERV */
281static inline bool hv_is_hyperv_initialized(void) { return false; }
282static inline bool hv_is_hibernation_supported(void) { return false; }
283static inline void hyperv_cleanup(void) {}
284static inline bool hv_is_isolation_supported(void) { return false; }
285static inline enum hv_isolation_type hv_get_isolation_type(void)
286{
287 return HV_ISOLATION_TYPE_NONE;
288}
289#endif /* CONFIG_HYPERV */
290
291#endif