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 31 struct 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 }; 52 extern struct ms_hyperv_info ms_hyperv; 53 extern bool hv_nested; 54 55 extern void * __percpu *hyperv_pcpu_input_arg; 56 extern void * __percpu *hyperv_pcpu_output_arg; 57 58 extern u64 hv_do_hypercall(u64 control, void *inputaddr, void *outputaddr); 59 extern u64 hv_do_fast_hypercall8(u16 control, u64 input8); 60 extern bool hv_isolation_type_snp(void); 61 62 /* Helper functions that provide a consistent pattern for checking Hyper-V hypercall status. */ 63 static inline int hv_result(u64 status) 64 { 65 return status & HV_HYPERCALL_RESULT_MASK; 66 } 67 68 static inline bool hv_result_success(u64 status) 69 { 70 return hv_result(status) == HV_STATUS_SUCCESS; 71 } 72 73 static 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 */ 84 static 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 */ 111 static 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 */ 122 static 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 } 155 156 void hv_setup_vmbus_handler(void (*handler)(void)); 157 void hv_remove_vmbus_handler(void); 158 void hv_setup_stimer0_handler(void (*handler)(void)); 159 void hv_remove_stimer0_handler(void); 160 161 void hv_setup_kexec_handler(void (*handler)(void)); 162 void hv_remove_kexec_handler(void); 163 void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs)); 164 void hv_remove_crash_handler(void); 165 166 extern int vmbus_interrupt; 167 extern int vmbus_irq; 168 169 extern 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 */ 178 extern u32 *hv_vp_index; 179 extern u32 hv_max_vp_index; 180 181 extern 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 185 186 int __init hv_common_init(void); 187 void __init hv_common_free(void); 188 int hv_common_cpu_init(unsigned int cpu); 189 int hv_common_cpu_die(unsigned int cpu); 190 191 void *hv_alloc_hyperv_page(void); 192 void *hv_alloc_hyperv_zeroed_page(void); 193 void 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 */ 206 static inline int hv_cpu_number_to_vp_number(int cpu_number) 207 { 208 return hv_vp_index[cpu_number]; 209 } 210 211 static 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 */ 257 static inline int cpumask_to_vpset(struct hv_vpset *vpset, 258 const struct cpumask *cpus) 259 { 260 return __cpumask_to_vpset(vpset, cpus, NULL); 261 } 262 263 static 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 } 269 270 void hyperv_report_panic(struct pt_regs *regs, long err, bool in_die); 271 bool hv_is_hyperv_initialized(void); 272 bool hv_is_hibernation_supported(void); 273 enum hv_isolation_type hv_get_isolation_type(void); 274 bool hv_is_isolation_supported(void); 275 bool hv_isolation_type_snp(void); 276 u64 hv_ghcb_hypercall(u64 control, void *input, void *output, u32 input_size); 277 void hyperv_cleanup(void); 278 bool hv_query_ext_cap(u64 cap_query); 279 void hv_setup_dma_ops(struct device *dev, bool coherent); 280 #else /* CONFIG_HYPERV */ 281 static inline bool hv_is_hyperv_initialized(void) { return false; } 282 static inline bool hv_is_hibernation_supported(void) { return false; } 283 static inline void hyperv_cleanup(void) {} 284 static inline bool hv_is_isolation_supported(void) { return false; } 285 static 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 292