1 /* SPDX-License-Identifier: GPL-2.0 */
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>.
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
13 * Copyright (C) 2019, Microsoft, Inc.
15 * Author : Michael Kelley <mikelley@microsoft.com>
18 #ifndef _ASM_GENERIC_MSHYPERV_H
19 #define _ASM_GENERIC_MSHYPERV_H
21 #include <linux/types.h>
22 #include <linux/atomic.h>
23 #include <linux/bitops.h>
24 #include <linux/cpumask.h>
25 #include <asm/ptrace.h>
26 #include <asm/hyperv-tlfs.h>
28 struct ms_hyperv_info {
36 u32 isolation_config_a;
37 u32 isolation_config_b;
39 extern struct ms_hyperv_info ms_hyperv;
41 extern u64 hv_do_hypercall(u64 control, void *inputaddr, void *outputaddr);
42 extern u64 hv_do_fast_hypercall8(u16 control, u64 input8);
44 /* Helper functions that provide a consistent pattern for checking Hyper-V hypercall status. */
45 static inline int hv_result(u64 status)
47 return status & HV_HYPERCALL_RESULT_MASK;
50 static inline bool hv_result_success(u64 status)
52 return hv_result(status) == HV_STATUS_SUCCESS;
55 static inline unsigned int hv_repcomp(u64 status)
57 /* Bits [43:32] of status have 'Reps completed' data. */
58 return (status & HV_HYPERCALL_REP_COMP_MASK) >>
59 HV_HYPERCALL_REP_COMP_OFFSET;
63 * Rep hypercalls. Callers of this functions are supposed to ensure that
64 * rep_count and varhead_size comply with Hyper-V hypercall definition.
66 static inline u64 hv_do_rep_hypercall(u16 code, u16 rep_count, u16 varhead_size,
67 void *input, void *output)
73 control |= (u64)varhead_size << HV_HYPERCALL_VARHEAD_OFFSET;
74 control |= (u64)rep_count << HV_HYPERCALL_REP_COMP_OFFSET;
77 status = hv_do_hypercall(control, input, output);
78 if (!hv_result_success(status))
81 rep_comp = hv_repcomp(status);
83 control &= ~HV_HYPERCALL_REP_START_MASK;
84 control |= (u64)rep_comp << HV_HYPERCALL_REP_START_OFFSET;
87 } while (rep_comp < rep_count);
92 /* Generate the guest OS identifier as described in the Hyper-V TLFS */
93 static inline __u64 generate_guest_id(__u64 d_info1, __u64 kernel_version,
98 guest_id = (((__u64)HV_LINUX_VENDOR_ID) << 48);
99 guest_id |= (d_info1 << 48);
100 guest_id |= (kernel_version << 16);
106 /* Free the message slot and signal end-of-message if required */
107 static inline void vmbus_signal_eom(struct hv_message *msg, u32 old_msg_type)
110 * On crash we're reading some other CPU's message page and we need
111 * to be careful: this other CPU may already had cleared the header
112 * and the host may already had delivered some other message there.
113 * In case we blindly write msg->header.message_type we're going
114 * to lose it. We can still lose a message of the same type but
115 * we count on the fact that there can only be one
116 * CHANNELMSG_UNLOAD_RESPONSE and we don't care about other messages
119 if (cmpxchg(&msg->header.message_type, old_msg_type,
120 HVMSG_NONE) != old_msg_type)
124 * The cmxchg() above does an implicit memory barrier to
125 * ensure the write to MessageType (ie set to
126 * HVMSG_NONE) happens before we read the
127 * MessagePending and EOMing. Otherwise, the EOMing
128 * will not deliver any more messages since there is
131 if (msg->header.message_flags.msg_pending) {
133 * This will cause message queue rescan to
134 * possibly deliver another msg from the
137 hv_set_register(HV_REGISTER_EOM, 0);
141 void hv_setup_vmbus_handler(void (*handler)(void));
142 void hv_remove_vmbus_handler(void);
143 void hv_setup_stimer0_handler(void (*handler)(void));
144 void hv_remove_stimer0_handler(void);
146 void hv_setup_kexec_handler(void (*handler)(void));
147 void hv_remove_kexec_handler(void);
148 void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs));
149 void hv_remove_crash_handler(void);
151 extern int vmbus_interrupt;
152 extern int vmbus_irq;
154 #if IS_ENABLED(CONFIG_HYPERV)
156 * Hypervisor's notion of virtual processor ID is different from
157 * Linux' notion of CPU ID. This information can only be retrieved
158 * in the context of the calling CPU. Setup a map for easy access
159 * to this information.
161 extern u32 *hv_vp_index;
162 extern u32 hv_max_vp_index;
164 /* Sentinel value for an uninitialized entry in hv_vp_index array */
165 #define VP_INVAL U32_MAX
167 void *hv_alloc_hyperv_page(void);
168 void *hv_alloc_hyperv_zeroed_page(void);
169 void hv_free_hyperv_page(unsigned long addr);
172 * hv_cpu_number_to_vp_number() - Map CPU to VP.
173 * @cpu_number: CPU number in Linux terms
175 * This function returns the mapping between the Linux processor
176 * number and the hypervisor's virtual processor number, useful
177 * in making hypercalls and such that talk about specific
180 * Return: Virtual processor number in Hyper-V terms
182 static inline int hv_cpu_number_to_vp_number(int cpu_number)
184 return hv_vp_index[cpu_number];
187 static inline int cpumask_to_vpset(struct hv_vpset *vpset,
188 const struct cpumask *cpus)
190 int cpu, vcpu, vcpu_bank, vcpu_offset, nr_bank = 1;
192 /* valid_bank_mask can represent up to 64 banks */
193 if (hv_max_vp_index / 64 >= 64)
197 * Clear all banks up to the maximum possible bank as hv_tlb_flush_ex
198 * structs are not cleared between calls, we risk flushing unneeded
201 for (vcpu_bank = 0; vcpu_bank <= hv_max_vp_index / 64; vcpu_bank++)
202 vpset->bank_contents[vcpu_bank] = 0;
205 * Some banks may end up being empty but this is acceptable.
207 for_each_cpu(cpu, cpus) {
208 vcpu = hv_cpu_number_to_vp_number(cpu);
209 if (vcpu == VP_INVAL)
211 vcpu_bank = vcpu / 64;
212 vcpu_offset = vcpu % 64;
213 __set_bit(vcpu_offset, (unsigned long *)
214 &vpset->bank_contents[vcpu_bank]);
215 if (vcpu_bank >= nr_bank)
216 nr_bank = vcpu_bank + 1;
218 vpset->valid_bank_mask = GENMASK_ULL(nr_bank - 1, 0);
222 void hyperv_report_panic(struct pt_regs *regs, long err, bool in_die);
223 bool hv_is_hyperv_initialized(void);
224 bool hv_is_hibernation_supported(void);
225 enum hv_isolation_type hv_get_isolation_type(void);
226 bool hv_is_isolation_supported(void);
227 void hyperv_cleanup(void);
228 bool hv_query_ext_cap(u64 cap_query);
229 #else /* CONFIG_HYPERV */
230 static inline bool hv_is_hyperv_initialized(void) { return false; }
231 static inline bool hv_is_hibernation_supported(void) { return false; }
232 static inline void hyperv_cleanup(void) {}
233 #endif /* CONFIG_HYPERV */