summaryrefslogtreecommitdiff
path: root/include/asm-generic/mshyperv.h
blob: 1c4fd950f09123d6802b0dd82be00757eb815992 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
/* SPDX-License-Identifier: GPL-2.0 */

/*
 * Linux-specific definitions for managing interactions with Microsoft's
 * Hyper-V hypervisor. The definitions in this file are architecture
 * independent. See arch/<arch>/include/asm/mshyperv.h for definitions
 * that are specific to architecture <arch>.
 *
 * Definitions that are specified in the Hyper-V Top Level Functional
 * Spec (TLFS) should not go in this file, but should instead go in
 * hyperv-tlfs.h.
 *
 * Copyright (C) 2019, Microsoft, Inc.
 *
 * Author : Michael Kelley <mikelley@microsoft.com>
 */

#ifndef _ASM_GENERIC_MSHYPERV_H
#define _ASM_GENERIC_MSHYPERV_H

#include <linux/types.h>
#include <linux/atomic.h>
#include <linux/bitops.h>
#include <linux/cpumask.h>
#include <asm/ptrace.h>
#include <asm/hyperv-tlfs.h>

struct ms_hyperv_info {
	u32 features;
	u32 misc_features;
	u32 hints;
	u32 nested_features;
	u32 max_vp_index;
	u32 max_lp_index;
};
extern struct ms_hyperv_info ms_hyperv;

extern u64 hv_do_hypercall(u64 control, void *inputaddr, void *outputaddr);
extern u64 hv_do_fast_hypercall8(u16 control, u64 input8);


/* Generate the guest OS identifier as described in the Hyper-V TLFS */
static inline  __u64 generate_guest_id(__u64 d_info1, __u64 kernel_version,
				       __u64 d_info2)
{
	__u64 guest_id = 0;

	guest_id = (((__u64)HV_LINUX_VENDOR_ID) << 48);
	guest_id |= (d_info1 << 48);
	guest_id |= (kernel_version << 16);
	guest_id |= d_info2;

	return guest_id;
}


/* Free the message slot and signal end-of-message if required */
static inline void vmbus_signal_eom(struct hv_message *msg, u32 old_msg_type)
{
	/*
	 * On crash we're reading some other CPU's message page and we need
	 * to be careful: this other CPU may already had cleared the header
	 * and the host may already had delivered some other message there.
	 * In case we blindly write msg->header.message_type we're going
	 * to lose it. We can still lose a message of the same type but
	 * we count on the fact that there can only be one
	 * CHANNELMSG_UNLOAD_RESPONSE and we don't care about other messages
	 * on crash.
	 */
	if (cmpxchg(&msg->header.message_type, old_msg_type,
		    HVMSG_NONE) != old_msg_type)
		return;

	/*
	 * The cmxchg() above does an implicit memory barrier to
	 * ensure the write to MessageType (ie set to
	 * HVMSG_NONE) happens before we read the
	 * MessagePending and EOMing. Otherwise, the EOMing
	 * will not deliver any more messages since there is
	 * no empty slot
	 */
	if (msg->header.message_flags.msg_pending) {
		/*
		 * This will cause message queue rescan to
		 * possibly deliver another msg from the
		 * hypervisor
		 */
		hv_signal_eom();
	}
}

void hv_setup_vmbus_irq(void (*handler)(void));
void hv_remove_vmbus_irq(void);
void hv_enable_vmbus_irq(void);
void hv_disable_vmbus_irq(void);

void hv_setup_kexec_handler(void (*handler)(void));
void hv_remove_kexec_handler(void);
void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs));
void hv_remove_crash_handler(void);

#if IS_ENABLED(CONFIG_HYPERV)
/*
 * Hypervisor's notion of virtual processor ID is different from
 * Linux' notion of CPU ID. This information can only be retrieved
 * in the context of the calling CPU. Setup a map for easy access
 * to this information.
 */
extern u32 *hv_vp_index;
extern u32 hv_max_vp_index;

/* Sentinel value for an uninitialized entry in hv_vp_index array */
#define VP_INVAL	U32_MAX

/**
 * hv_cpu_number_to_vp_number() - Map CPU to VP.
 * @cpu_number: CPU number in Linux terms
 *
 * This function returns the mapping between the Linux processor
 * number and the hypervisor's virtual processor number, useful
 * in making hypercalls and such that talk about specific
 * processors.
 *
 * Return: Virtual processor number in Hyper-V terms
 */
static inline int hv_cpu_number_to_vp_number(int cpu_number)
{
	return hv_vp_index[cpu_number];
}

static inline int cpumask_to_vpset(struct hv_vpset *vpset,
				    const struct cpumask *cpus)
{
	int cpu, vcpu, vcpu_bank, vcpu_offset, nr_bank = 1;

	/* valid_bank_mask can represent up to 64 banks */
	if (hv_max_vp_index / 64 >= 64)
		return 0;

	/*
	 * Clear all banks up to the maximum possible bank as hv_tlb_flush_ex
	 * structs are not cleared between calls, we risk flushing unneeded
	 * vCPUs otherwise.
	 */
	for (vcpu_bank = 0; vcpu_bank <= hv_max_vp_index / 64; vcpu_bank++)
		vpset->bank_contents[vcpu_bank] = 0;

	/*
	 * Some banks may end up being empty but this is acceptable.
	 */
	for_each_cpu(cpu, cpus) {
		vcpu = hv_cpu_number_to_vp_number(cpu);
		if (vcpu == VP_INVAL)
			return -1;
		vcpu_bank = vcpu / 64;
		vcpu_offset = vcpu % 64;
		__set_bit(vcpu_offset, (unsigned long *)
			  &vpset->bank_contents[vcpu_bank]);
		if (vcpu_bank >= nr_bank)
			nr_bank = vcpu_bank + 1;
	}
	vpset->valid_bank_mask = GENMASK_ULL(nr_bank - 1, 0);
	return nr_bank;
}

void hyperv_report_panic(struct pt_regs *regs, long err, bool in_die);
void hyperv_report_panic_msg(phys_addr_t pa, size_t size);
bool hv_is_hyperv_initialized(void);
bool hv_is_hibernation_supported(void);
void hyperv_cleanup(void);
void hv_setup_sched_clock(void *sched_clock);
#else /* CONFIG_HYPERV */
static inline bool hv_is_hyperv_initialized(void) { return false; }
static inline bool hv_is_hibernation_supported(void) { return false; }
static inline void hyperv_cleanup(void) {}
#endif /* CONFIG_HYPERV */

#if IS_ENABLED(CONFIG_HYPERV)
extern int hv_setup_stimer0_irq(int *irq, int *vector, void (*handler)(void));
extern void hv_remove_stimer0_irq(int irq);
#endif

#endif