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 <asm/ptrace.h> 26 #include <asm/hyperv-tlfs.h> 27 28 struct ms_hyperv_info { 29 u32 features; 30 u32 features_b; 31 u32 misc_features; 32 u32 hints; 33 u32 nested_features; 34 u32 max_vp_index; 35 u32 max_lp_index; 36 u32 isolation_config_a; 37 u32 isolation_config_b; 38 }; 39 extern struct ms_hyperv_info ms_hyperv; 40 41 extern u64 hv_do_hypercall(u64 control, void *inputaddr, void *outputaddr); 42 extern u64 hv_do_fast_hypercall8(u16 control, u64 input8); 43 44 45 /* Generate the guest OS identifier as described in the Hyper-V TLFS */ 46 static inline __u64 generate_guest_id(__u64 d_info1, __u64 kernel_version, 47 __u64 d_info2) 48 { 49 __u64 guest_id = 0; 50 51 guest_id = (((__u64)HV_LINUX_VENDOR_ID) << 48); 52 guest_id |= (d_info1 << 48); 53 guest_id |= (kernel_version << 16); 54 guest_id |= d_info2; 55 56 return guest_id; 57 } 58 59 60 /* Free the message slot and signal end-of-message if required */ 61 static inline void vmbus_signal_eom(struct hv_message *msg, u32 old_msg_type) 62 { 63 /* 64 * On crash we're reading some other CPU's message page and we need 65 * to be careful: this other CPU may already had cleared the header 66 * and the host may already had delivered some other message there. 67 * In case we blindly write msg->header.message_type we're going 68 * to lose it. We can still lose a message of the same type but 69 * we count on the fact that there can only be one 70 * CHANNELMSG_UNLOAD_RESPONSE and we don't care about other messages 71 * on crash. 72 */ 73 if (cmpxchg(&msg->header.message_type, old_msg_type, 74 HVMSG_NONE) != old_msg_type) 75 return; 76 77 /* 78 * The cmxchg() above does an implicit memory barrier to 79 * ensure the write to MessageType (ie set to 80 * HVMSG_NONE) happens before we read the 81 * MessagePending and EOMing. Otherwise, the EOMing 82 * will not deliver any more messages since there is 83 * no empty slot 84 */ 85 if (msg->header.message_flags.msg_pending) { 86 /* 87 * This will cause message queue rescan to 88 * possibly deliver another msg from the 89 * hypervisor 90 */ 91 hv_signal_eom(); 92 } 93 } 94 95 int hv_setup_vmbus_irq(int irq, void (*handler)(void)); 96 void hv_remove_vmbus_irq(void); 97 void hv_enable_vmbus_irq(void); 98 void hv_disable_vmbus_irq(void); 99 100 void hv_setup_kexec_handler(void (*handler)(void)); 101 void hv_remove_kexec_handler(void); 102 void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs)); 103 void hv_remove_crash_handler(void); 104 105 extern int vmbus_interrupt; 106 107 #if IS_ENABLED(CONFIG_HYPERV) 108 /* 109 * Hypervisor's notion of virtual processor ID is different from 110 * Linux' notion of CPU ID. This information can only be retrieved 111 * in the context of the calling CPU. Setup a map for easy access 112 * to this information. 113 */ 114 extern u32 *hv_vp_index; 115 extern u32 hv_max_vp_index; 116 117 /* Sentinel value for an uninitialized entry in hv_vp_index array */ 118 #define VP_INVAL U32_MAX 119 120 /** 121 * hv_cpu_number_to_vp_number() - Map CPU to VP. 122 * @cpu_number: CPU number in Linux terms 123 * 124 * This function returns the mapping between the Linux processor 125 * number and the hypervisor's virtual processor number, useful 126 * in making hypercalls and such that talk about specific 127 * processors. 128 * 129 * Return: Virtual processor number in Hyper-V terms 130 */ 131 static inline int hv_cpu_number_to_vp_number(int cpu_number) 132 { 133 return hv_vp_index[cpu_number]; 134 } 135 136 static inline int cpumask_to_vpset(struct hv_vpset *vpset, 137 const struct cpumask *cpus) 138 { 139 int cpu, vcpu, vcpu_bank, vcpu_offset, nr_bank = 1; 140 141 /* valid_bank_mask can represent up to 64 banks */ 142 if (hv_max_vp_index / 64 >= 64) 143 return 0; 144 145 /* 146 * Clear all banks up to the maximum possible bank as hv_tlb_flush_ex 147 * structs are not cleared between calls, we risk flushing unneeded 148 * vCPUs otherwise. 149 */ 150 for (vcpu_bank = 0; vcpu_bank <= hv_max_vp_index / 64; vcpu_bank++) 151 vpset->bank_contents[vcpu_bank] = 0; 152 153 /* 154 * Some banks may end up being empty but this is acceptable. 155 */ 156 for_each_cpu(cpu, cpus) { 157 vcpu = hv_cpu_number_to_vp_number(cpu); 158 if (vcpu == VP_INVAL) 159 return -1; 160 vcpu_bank = vcpu / 64; 161 vcpu_offset = vcpu % 64; 162 __set_bit(vcpu_offset, (unsigned long *) 163 &vpset->bank_contents[vcpu_bank]); 164 if (vcpu_bank >= nr_bank) 165 nr_bank = vcpu_bank + 1; 166 } 167 vpset->valid_bank_mask = GENMASK_ULL(nr_bank - 1, 0); 168 return nr_bank; 169 } 170 171 void hyperv_report_panic(struct pt_regs *regs, long err, bool in_die); 172 void hyperv_report_panic_msg(phys_addr_t pa, size_t size); 173 bool hv_is_hyperv_initialized(void); 174 bool hv_is_hibernation_supported(void); 175 enum hv_isolation_type hv_get_isolation_type(void); 176 bool hv_is_isolation_supported(void); 177 void hyperv_cleanup(void); 178 #else /* CONFIG_HYPERV */ 179 static inline bool hv_is_hyperv_initialized(void) { return false; } 180 static inline bool hv_is_hibernation_supported(void) { return false; } 181 static inline void hyperv_cleanup(void) {} 182 #endif /* CONFIG_HYPERV */ 183 184 #if IS_ENABLED(CONFIG_HYPERV) 185 extern int hv_setup_stimer0_irq(int *irq, int *vector, void (*handler)(void)); 186 extern void hv_remove_stimer0_irq(int irq); 187 #endif 188 189 #endif 190