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