1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_X86_MSHYPER_H 3 #define _ASM_X86_MSHYPER_H 4 5 #include <linux/types.h> 6 #include <linux/atomic.h> 7 #include <linux/nmi.h> 8 #include <asm/io.h> 9 #include <asm/hyperv-tlfs.h> 10 #include <asm/nospec-branch.h> 11 12 struct ms_hyperv_info { 13 u32 features; 14 u32 misc_features; 15 u32 hints; 16 u32 nested_features; 17 u32 max_vp_index; 18 u32 max_lp_index; 19 }; 20 21 extern struct ms_hyperv_info ms_hyperv; 22 23 24 /* 25 * Generate the guest ID. 26 */ 27 28 static inline __u64 generate_guest_id(__u64 d_info1, __u64 kernel_version, 29 __u64 d_info2) 30 { 31 __u64 guest_id = 0; 32 33 guest_id = (((__u64)HV_LINUX_VENDOR_ID) << 48); 34 guest_id |= (d_info1 << 48); 35 guest_id |= (kernel_version << 16); 36 guest_id |= d_info2; 37 38 return guest_id; 39 } 40 41 42 /* Free the message slot and signal end-of-message if required */ 43 static inline void vmbus_signal_eom(struct hv_message *msg, u32 old_msg_type) 44 { 45 /* 46 * On crash we're reading some other CPU's message page and we need 47 * to be careful: this other CPU may already had cleared the header 48 * and the host may already had delivered some other message there. 49 * In case we blindly write msg->header.message_type we're going 50 * to lose it. We can still lose a message of the same type but 51 * we count on the fact that there can only be one 52 * CHANNELMSG_UNLOAD_RESPONSE and we don't care about other messages 53 * on crash. 54 */ 55 if (cmpxchg(&msg->header.message_type, old_msg_type, 56 HVMSG_NONE) != old_msg_type) 57 return; 58 59 /* 60 * Make sure the write to MessageType (ie set to 61 * HVMSG_NONE) happens before we read the 62 * MessagePending and EOMing. Otherwise, the EOMing 63 * will not deliver any more messages since there is 64 * no empty slot 65 */ 66 mb(); 67 68 if (msg->header.message_flags.msg_pending) { 69 /* 70 * This will cause message queue rescan to 71 * possibly deliver another msg from the 72 * hypervisor 73 */ 74 wrmsrl(HV_X64_MSR_EOM, 0); 75 } 76 } 77 78 #define hv_init_timer(timer, tick) wrmsrl(timer, tick) 79 #define hv_init_timer_config(config, val) wrmsrl(config, val) 80 81 #define hv_get_simp(val) rdmsrl(HV_X64_MSR_SIMP, val) 82 #define hv_set_simp(val) wrmsrl(HV_X64_MSR_SIMP, val) 83 84 #define hv_get_siefp(val) rdmsrl(HV_X64_MSR_SIEFP, val) 85 #define hv_set_siefp(val) wrmsrl(HV_X64_MSR_SIEFP, val) 86 87 #define hv_get_synic_state(val) rdmsrl(HV_X64_MSR_SCONTROL, val) 88 #define hv_set_synic_state(val) wrmsrl(HV_X64_MSR_SCONTROL, val) 89 90 #define hv_get_vp_index(index) rdmsrl(HV_X64_MSR_VP_INDEX, index) 91 92 #define hv_get_synint_state(int_num, val) rdmsrl(int_num, val) 93 #define hv_set_synint_state(int_num, val) wrmsrl(int_num, val) 94 95 void hyperv_callback_vector(void); 96 void hyperv_reenlightenment_vector(void); 97 #ifdef CONFIG_TRACING 98 #define trace_hyperv_callback_vector hyperv_callback_vector 99 #endif 100 void hyperv_vector_handler(struct pt_regs *regs); 101 void hv_setup_vmbus_irq(void (*handler)(void)); 102 void hv_remove_vmbus_irq(void); 103 104 void hv_setup_kexec_handler(void (*handler)(void)); 105 void hv_remove_kexec_handler(void); 106 void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs)); 107 void hv_remove_crash_handler(void); 108 109 /* 110 * Routines for stimer0 Direct Mode handling. 111 * On x86/x64, there are no percpu actions to take. 112 */ 113 void hv_stimer0_vector_handler(struct pt_regs *regs); 114 void hv_stimer0_callback_vector(void); 115 int hv_setup_stimer0_irq(int *irq, int *vector, void (*handler)(void)); 116 void hv_remove_stimer0_irq(int irq); 117 118 static inline void hv_enable_stimer0_percpu_irq(int irq) {} 119 static inline void hv_disable_stimer0_percpu_irq(int irq) {} 120 121 122 #if IS_ENABLED(CONFIG_HYPERV) 123 extern struct clocksource *hyperv_cs; 124 extern void *hv_hypercall_pg; 125 126 static inline u64 hv_do_hypercall(u64 control, void *input, void *output) 127 { 128 u64 input_address = input ? virt_to_phys(input) : 0; 129 u64 output_address = output ? virt_to_phys(output) : 0; 130 u64 hv_status; 131 132 #ifdef CONFIG_X86_64 133 if (!hv_hypercall_pg) 134 return U64_MAX; 135 136 __asm__ __volatile__("mov %4, %%r8\n" 137 CALL_NOSPEC 138 : "=a" (hv_status), ASM_CALL_CONSTRAINT, 139 "+c" (control), "+d" (input_address) 140 : "r" (output_address), 141 THUNK_TARGET(hv_hypercall_pg) 142 : "cc", "memory", "r8", "r9", "r10", "r11"); 143 #else 144 u32 input_address_hi = upper_32_bits(input_address); 145 u32 input_address_lo = lower_32_bits(input_address); 146 u32 output_address_hi = upper_32_bits(output_address); 147 u32 output_address_lo = lower_32_bits(output_address); 148 149 if (!hv_hypercall_pg) 150 return U64_MAX; 151 152 __asm__ __volatile__(CALL_NOSPEC 153 : "=A" (hv_status), 154 "+c" (input_address_lo), ASM_CALL_CONSTRAINT 155 : "A" (control), 156 "b" (input_address_hi), 157 "D"(output_address_hi), "S"(output_address_lo), 158 THUNK_TARGET(hv_hypercall_pg) 159 : "cc", "memory"); 160 #endif /* !x86_64 */ 161 return hv_status; 162 } 163 164 /* Fast hypercall with 8 bytes of input and no output */ 165 static inline u64 hv_do_fast_hypercall8(u16 code, u64 input1) 166 { 167 u64 hv_status, control = (u64)code | HV_HYPERCALL_FAST_BIT; 168 169 #ifdef CONFIG_X86_64 170 { 171 __asm__ __volatile__(CALL_NOSPEC 172 : "=a" (hv_status), ASM_CALL_CONSTRAINT, 173 "+c" (control), "+d" (input1) 174 : THUNK_TARGET(hv_hypercall_pg) 175 : "cc", "r8", "r9", "r10", "r11"); 176 } 177 #else 178 { 179 u32 input1_hi = upper_32_bits(input1); 180 u32 input1_lo = lower_32_bits(input1); 181 182 __asm__ __volatile__ (CALL_NOSPEC 183 : "=A"(hv_status), 184 "+c"(input1_lo), 185 ASM_CALL_CONSTRAINT 186 : "A" (control), 187 "b" (input1_hi), 188 THUNK_TARGET(hv_hypercall_pg) 189 : "cc", "edi", "esi"); 190 } 191 #endif 192 return hv_status; 193 } 194 195 /* 196 * Rep hypercalls. Callers of this functions are supposed to ensure that 197 * rep_count and varhead_size comply with Hyper-V hypercall definition. 198 */ 199 static inline u64 hv_do_rep_hypercall(u16 code, u16 rep_count, u16 varhead_size, 200 void *input, void *output) 201 { 202 u64 control = code; 203 u64 status; 204 u16 rep_comp; 205 206 control |= (u64)varhead_size << HV_HYPERCALL_VARHEAD_OFFSET; 207 control |= (u64)rep_count << HV_HYPERCALL_REP_COMP_OFFSET; 208 209 do { 210 status = hv_do_hypercall(control, input, output); 211 if ((status & HV_HYPERCALL_RESULT_MASK) != HV_STATUS_SUCCESS) 212 return status; 213 214 /* Bits 32-43 of status have 'Reps completed' data. */ 215 rep_comp = (status & HV_HYPERCALL_REP_COMP_MASK) >> 216 HV_HYPERCALL_REP_COMP_OFFSET; 217 218 control &= ~HV_HYPERCALL_REP_START_MASK; 219 control |= (u64)rep_comp << HV_HYPERCALL_REP_START_OFFSET; 220 221 touch_nmi_watchdog(); 222 } while (rep_comp < rep_count); 223 224 return status; 225 } 226 227 /* 228 * Hypervisor's notion of virtual processor ID is different from 229 * Linux' notion of CPU ID. This information can only be retrieved 230 * in the context of the calling CPU. Setup a map for easy access 231 * to this information. 232 */ 233 extern u32 *hv_vp_index; 234 extern u32 hv_max_vp_index; 235 extern struct hv_vp_assist_page **hv_vp_assist_page; 236 237 static inline struct hv_vp_assist_page *hv_get_vp_assist_page(unsigned int cpu) 238 { 239 if (!hv_vp_assist_page) 240 return NULL; 241 242 return hv_vp_assist_page[cpu]; 243 } 244 245 /** 246 * hv_cpu_number_to_vp_number() - Map CPU to VP. 247 * @cpu_number: CPU number in Linux terms 248 * 249 * This function returns the mapping between the Linux processor 250 * number and the hypervisor's virtual processor number, useful 251 * in making hypercalls and such that talk about specific 252 * processors. 253 * 254 * Return: Virtual processor number in Hyper-V terms 255 */ 256 static inline int hv_cpu_number_to_vp_number(int cpu_number) 257 { 258 return hv_vp_index[cpu_number]; 259 } 260 261 void hyperv_init(void); 262 void hyperv_setup_mmu_ops(void); 263 void hyper_alloc_mmu(void); 264 void hyperv_report_panic(struct pt_regs *regs, long err); 265 bool hv_is_hyperv_initialized(void); 266 void hyperv_cleanup(void); 267 268 void hyperv_reenlightenment_intr(struct pt_regs *regs); 269 void set_hv_tscchange_cb(void (*cb)(void)); 270 void clear_hv_tscchange_cb(void); 271 void hyperv_stop_tsc_emulation(void); 272 #else /* CONFIG_HYPERV */ 273 static inline void hyperv_init(void) {} 274 static inline bool hv_is_hyperv_initialized(void) { return false; } 275 static inline void hyperv_cleanup(void) {} 276 static inline void hyperv_setup_mmu_ops(void) {} 277 static inline void set_hv_tscchange_cb(void (*cb)(void)) {} 278 static inline void clear_hv_tscchange_cb(void) {} 279 static inline void hyperv_stop_tsc_emulation(void) {}; 280 static inline struct hv_vp_assist_page *hv_get_vp_assist_page(unsigned int cpu) 281 { 282 return NULL; 283 } 284 #endif /* CONFIG_HYPERV */ 285 286 #ifdef CONFIG_HYPERV_TSCPAGE 287 struct ms_hyperv_tsc_page *hv_get_tsc_page(void); 288 static inline u64 hv_read_tsc_page_tsc(const struct ms_hyperv_tsc_page *tsc_pg, 289 u64 *cur_tsc) 290 { 291 u64 scale, offset; 292 u32 sequence; 293 294 /* 295 * The protocol for reading Hyper-V TSC page is specified in Hypervisor 296 * Top-Level Functional Specification ver. 3.0 and above. To get the 297 * reference time we must do the following: 298 * - READ ReferenceTscSequence 299 * A special '0' value indicates the time source is unreliable and we 300 * need to use something else. The currently published specification 301 * versions (up to 4.0b) contain a mistake and wrongly claim '-1' 302 * instead of '0' as the special value, see commit c35b82ef0294. 303 * - ReferenceTime = 304 * ((RDTSC() * ReferenceTscScale) >> 64) + ReferenceTscOffset 305 * - READ ReferenceTscSequence again. In case its value has changed 306 * since our first reading we need to discard ReferenceTime and repeat 307 * the whole sequence as the hypervisor was updating the page in 308 * between. 309 */ 310 do { 311 sequence = READ_ONCE(tsc_pg->tsc_sequence); 312 if (!sequence) 313 return U64_MAX; 314 /* 315 * Make sure we read sequence before we read other values from 316 * TSC page. 317 */ 318 smp_rmb(); 319 320 scale = READ_ONCE(tsc_pg->tsc_scale); 321 offset = READ_ONCE(tsc_pg->tsc_offset); 322 *cur_tsc = rdtsc_ordered(); 323 324 /* 325 * Make sure we read sequence after we read all other values 326 * from TSC page. 327 */ 328 smp_rmb(); 329 330 } while (READ_ONCE(tsc_pg->tsc_sequence) != sequence); 331 332 return mul_u64_u64_shr(*cur_tsc, scale, 64) + offset; 333 } 334 335 static inline u64 hv_read_tsc_page(const struct ms_hyperv_tsc_page *tsc_pg) 336 { 337 u64 cur_tsc; 338 339 return hv_read_tsc_page_tsc(tsc_pg, &cur_tsc); 340 } 341 342 #else 343 static inline struct ms_hyperv_tsc_page *hv_get_tsc_page(void) 344 { 345 return NULL; 346 } 347 348 static inline u64 hv_read_tsc_page_tsc(const struct ms_hyperv_tsc_page *tsc_pg, 349 u64 *cur_tsc) 350 { 351 BUG(); 352 return U64_MAX; 353 } 354 #endif 355 #endif 356