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 union { 40 u32 isolation_config_a; 41 struct { 42 u32 paravisor_present : 1; 43 u32 reserved_a1 : 31; 44 }; 45 }; 46 union { 47 u32 isolation_config_b; 48 struct { 49 u32 cvm_type : 4; 50 u32 reserved_b1 : 1; 51 u32 shared_gpa_boundary_active : 1; 52 u32 shared_gpa_boundary_bits : 6; 53 u32 reserved_b2 : 20; 54 }; 55 }; 56 u64 shared_gpa_boundary; 57 u8 vtl; 58 }; 59 extern struct ms_hyperv_info ms_hyperv; 60 extern bool hv_nested; 61 62 extern void * __percpu *hyperv_pcpu_input_arg; 63 extern void * __percpu *hyperv_pcpu_output_arg; 64 65 extern u64 hv_do_hypercall(u64 control, void *inputaddr, void *outputaddr); 66 extern u64 hv_do_fast_hypercall8(u16 control, u64 input8); 67 bool hv_isolation_type_snp(void); 68 bool hv_isolation_type_tdx(void); 69 70 /* Helper functions that provide a consistent pattern for checking Hyper-V hypercall status. */ 71 static inline int hv_result(u64 status) 72 { 73 return status & HV_HYPERCALL_RESULT_MASK; 74 } 75 76 static inline bool hv_result_success(u64 status) 77 { 78 return hv_result(status) == HV_STATUS_SUCCESS; 79 } 80 81 static inline unsigned int hv_repcomp(u64 status) 82 { 83 /* Bits [43:32] of status have 'Reps completed' data. */ 84 return (status & HV_HYPERCALL_REP_COMP_MASK) >> 85 HV_HYPERCALL_REP_COMP_OFFSET; 86 } 87 88 /* 89 * Rep hypercalls. Callers of this functions are supposed to ensure that 90 * rep_count and varhead_size comply with Hyper-V hypercall definition. 91 */ 92 static inline u64 hv_do_rep_hypercall(u16 code, u16 rep_count, u16 varhead_size, 93 void *input, void *output) 94 { 95 u64 control = code; 96 u64 status; 97 u16 rep_comp; 98 99 control |= (u64)varhead_size << HV_HYPERCALL_VARHEAD_OFFSET; 100 control |= (u64)rep_count << HV_HYPERCALL_REP_COMP_OFFSET; 101 102 do { 103 status = hv_do_hypercall(control, input, output); 104 if (!hv_result_success(status)) 105 return status; 106 107 rep_comp = hv_repcomp(status); 108 109 control &= ~HV_HYPERCALL_REP_START_MASK; 110 control |= (u64)rep_comp << HV_HYPERCALL_REP_START_OFFSET; 111 112 touch_nmi_watchdog(); 113 } while (rep_comp < rep_count); 114 115 return status; 116 } 117 118 /* Generate the guest OS identifier as described in the Hyper-V TLFS */ 119 static inline u64 hv_generate_guest_id(u64 kernel_version) 120 { 121 u64 guest_id; 122 123 guest_id = (((u64)HV_LINUX_VENDOR_ID) << 48); 124 guest_id |= (kernel_version << 16); 125 126 return guest_id; 127 } 128 129 /* Free the message slot and signal end-of-message if required */ 130 static inline void vmbus_signal_eom(struct hv_message *msg, u32 old_msg_type) 131 { 132 /* 133 * On crash we're reading some other CPU's message page and we need 134 * to be careful: this other CPU may already had cleared the header 135 * and the host may already had delivered some other message there. 136 * In case we blindly write msg->header.message_type we're going 137 * to lose it. We can still lose a message of the same type but 138 * we count on the fact that there can only be one 139 * CHANNELMSG_UNLOAD_RESPONSE and we don't care about other messages 140 * on crash. 141 */ 142 if (cmpxchg(&msg->header.message_type, old_msg_type, 143 HVMSG_NONE) != old_msg_type) 144 return; 145 146 /* 147 * The cmxchg() above does an implicit memory barrier to 148 * ensure the write to MessageType (ie set to 149 * HVMSG_NONE) happens before we read the 150 * MessagePending and EOMing. Otherwise, the EOMing 151 * will not deliver any more messages since there is 152 * no empty slot 153 */ 154 if (msg->header.message_flags.msg_pending) { 155 /* 156 * This will cause message queue rescan to 157 * possibly deliver another msg from the 158 * hypervisor 159 */ 160 hv_set_register(HV_REGISTER_EOM, 0); 161 } 162 } 163 164 void hv_setup_vmbus_handler(void (*handler)(void)); 165 void hv_remove_vmbus_handler(void); 166 void hv_setup_stimer0_handler(void (*handler)(void)); 167 void hv_remove_stimer0_handler(void); 168 169 void hv_setup_kexec_handler(void (*handler)(void)); 170 void hv_remove_kexec_handler(void); 171 void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs)); 172 void hv_remove_crash_handler(void); 173 174 extern int vmbus_interrupt; 175 extern int vmbus_irq; 176 177 extern bool hv_root_partition; 178 179 #if IS_ENABLED(CONFIG_HYPERV) 180 /* 181 * Hypervisor's notion of virtual processor ID is different from 182 * Linux' notion of CPU ID. This information can only be retrieved 183 * in the context of the calling CPU. Setup a map for easy access 184 * to this information. 185 */ 186 extern u32 *hv_vp_index; 187 extern u32 hv_max_vp_index; 188 189 extern u64 (*hv_read_reference_counter)(void); 190 191 /* Sentinel value for an uninitialized entry in hv_vp_index array */ 192 #define VP_INVAL U32_MAX 193 194 int __init hv_common_init(void); 195 void __init hv_common_free(void); 196 int hv_common_cpu_init(unsigned int cpu); 197 int hv_common_cpu_die(unsigned int cpu); 198 199 void *hv_alloc_hyperv_page(void); 200 void *hv_alloc_hyperv_zeroed_page(void); 201 void hv_free_hyperv_page(void *addr); 202 203 /** 204 * hv_cpu_number_to_vp_number() - Map CPU to VP. 205 * @cpu_number: CPU number in Linux terms 206 * 207 * This function returns the mapping between the Linux processor 208 * number and the hypervisor's virtual processor number, useful 209 * in making hypercalls and such that talk about specific 210 * processors. 211 * 212 * Return: Virtual processor number in Hyper-V terms 213 */ 214 static inline int hv_cpu_number_to_vp_number(int cpu_number) 215 { 216 return hv_vp_index[cpu_number]; 217 } 218 219 static inline int __cpumask_to_vpset(struct hv_vpset *vpset, 220 const struct cpumask *cpus, 221 bool (*func)(int cpu)) 222 { 223 int cpu, vcpu, vcpu_bank, vcpu_offset, nr_bank = 1; 224 int max_vcpu_bank = hv_max_vp_index / HV_VCPUS_PER_SPARSE_BANK; 225 226 /* vpset.valid_bank_mask can represent up to HV_MAX_SPARSE_VCPU_BANKS banks */ 227 if (max_vcpu_bank >= HV_MAX_SPARSE_VCPU_BANKS) 228 return 0; 229 230 /* 231 * Clear all banks up to the maximum possible bank as hv_tlb_flush_ex 232 * structs are not cleared between calls, we risk flushing unneeded 233 * vCPUs otherwise. 234 */ 235 for (vcpu_bank = 0; vcpu_bank <= max_vcpu_bank; vcpu_bank++) 236 vpset->bank_contents[vcpu_bank] = 0; 237 238 /* 239 * Some banks may end up being empty but this is acceptable. 240 */ 241 for_each_cpu(cpu, cpus) { 242 if (func && func(cpu)) 243 continue; 244 vcpu = hv_cpu_number_to_vp_number(cpu); 245 if (vcpu == VP_INVAL) 246 return -1; 247 vcpu_bank = vcpu / HV_VCPUS_PER_SPARSE_BANK; 248 vcpu_offset = vcpu % HV_VCPUS_PER_SPARSE_BANK; 249 __set_bit(vcpu_offset, (unsigned long *) 250 &vpset->bank_contents[vcpu_bank]); 251 if (vcpu_bank >= nr_bank) 252 nr_bank = vcpu_bank + 1; 253 } 254 vpset->valid_bank_mask = GENMASK_ULL(nr_bank - 1, 0); 255 return nr_bank; 256 } 257 258 /* 259 * Convert a Linux cpumask into a Hyper-V VPset. In the _skip variant, 260 * 'func' is called for each CPU present in cpumask. If 'func' returns 261 * true, that CPU is skipped -- i.e., that CPU from cpumask is *not* 262 * added to the Hyper-V VPset. If 'func' is NULL, no CPUs are 263 * skipped. 264 */ 265 static inline int cpumask_to_vpset(struct hv_vpset *vpset, 266 const struct cpumask *cpus) 267 { 268 return __cpumask_to_vpset(vpset, cpus, NULL); 269 } 270 271 static inline int cpumask_to_vpset_skip(struct hv_vpset *vpset, 272 const struct cpumask *cpus, 273 bool (*func)(int cpu)) 274 { 275 return __cpumask_to_vpset(vpset, cpus, func); 276 } 277 278 void hyperv_report_panic(struct pt_regs *regs, long err, bool in_die); 279 bool hv_is_hyperv_initialized(void); 280 bool hv_is_hibernation_supported(void); 281 enum hv_isolation_type hv_get_isolation_type(void); 282 bool hv_is_isolation_supported(void); 283 bool hv_isolation_type_snp(void); 284 u64 hv_ghcb_hypercall(u64 control, void *input, void *output, u32 input_size); 285 u64 hv_tdx_hypercall(u64 control, u64 param1, u64 param2); 286 void hyperv_cleanup(void); 287 bool hv_query_ext_cap(u64 cap_query); 288 void hv_setup_dma_ops(struct device *dev, bool coherent); 289 #else /* CONFIG_HYPERV */ 290 static inline bool hv_is_hyperv_initialized(void) { return false; } 291 static inline bool hv_is_hibernation_supported(void) { return false; } 292 static inline void hyperv_cleanup(void) {} 293 static inline bool hv_is_isolation_supported(void) { return false; } 294 static inline enum hv_isolation_type hv_get_isolation_type(void) 295 { 296 return HV_ISOLATION_TYPE_NONE; 297 } 298 #endif /* CONFIG_HYPERV */ 299 300 #endif 301